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Sample records for diophantine frobenius problem

  1. Diophantine Optics

    NASA Astrophysics Data System (ADS)

    Rouan, D.

    2016-09-01

    What I call Diophantine optics is the exploitation in optics of some remarkable algebraic relations between powers of integers. The name comes from Diophantus of Alexandria, a greek mathematician, known as the father of algebra. He studied polynomial equations with integer coefficients and integer solutions, called diophantine equations. Since constructive or destructive interferences are playing with optical path differences which are multiple integer (odd or even) of λ/2 and that the complex amplitude is a highly non-linear function of the optical path difference (or equivalently of the phase), one can understand that any Taylor development of this amplitude implies powers of integers. This is the link with Diophantine equations. We show how, especially in the field of interferometry, remarkable relations between powers of integers can help to solve several problems, such as achromatization of a phase shifter or deep nulling efficiency. It appears that all the research that was conducted in this frame of thinking, relates to the field of detection of exoplanets, a very active domain of astrophysics today.

  2. Diophantine equations related to quasicrystals: A note

    NASA Astrophysics Data System (ADS)

    Pelantová, E.; Perelomov, A. M.

    1998-06-01

    We give the general solution of three Diophantine equations in the ring of integer of the algebraic number field ${\\bf Q}[{\\sqr 5}]$. These equations are related to the problem of determination of the minimum distance in quasicrystals with fivefold symmetry.

  3. On the Frobenius problem for three arguments

    NASA Astrophysics Data System (ADS)

    Vorob'ev, I. S.

    2016-06-01

    Asymptotic formulae for the mean values of various characteristics of the additive semigroup generated by three positive integers are obtained theoretically, the first of which is a formula for the number of integers not belonging to this semigroup. A numerical experiment is described which validates the results obtained. Bibliography: 21 titles.

  4. Un scindage du morphisme de Frobenius quantique

    NASA Astrophysics Data System (ADS)

    Gros, Michel; Kaneda, Masaharu

    2015-10-01

    We show that the quantum Frobenius morphism constructed by Lusztig in the setting of the quantum enveloping algebra specialized at a root of unity admits a (nonunital) multiplicative splitting. We construct the splitting using a basis of the toral part of the small quantum algebra consisting of pairwise orthogonal idempotents summing up to 1, and likewise in the modular case of the algebra of distributions for a semisimple algebraic group.

  5. Frobenius-Chern-Simons gauge theory

    NASA Astrophysics Data System (ADS)

    Bonezzi, Roberto; Boulanger, Nicolas; Sezgin, Ergin; Sundell, Per

    2017-02-01

    Given a set of differential forms on an odd-dimensional noncommutative manifold valued in an internal associative algebra H , we show that the most general cubic covariant Hamiltonian action, without mass terms, is controlled by an {{{Z}}2} -graded associative algebra F with a graded symmetric nondegenerate bilinear form. The resulting class of models provide a natural generalization of the Frobenius-Chern-Simons model (FCS) that was proposed in (arXiv:1505.04957) as an off-shell formulation of the minimal bosonic four-dimensional higher spin gravity theory. If F is unital and the {{{Z}}2} -grading is induced from a Klein operator that is outer to a proper Frobenius subalgebra, then the action can be written on a form akin to topological open string field theory in terms of a superconnection valued in H\\otimes F . We give a new model of this type based on a twisting of {C}≤ft[{{{Z}}2}× {{{Z}}4}\\right] , which leads to self-dual complexified gauge fields on AdS 4. If F is 3-graded, the FCS model can be truncated consistently as to contain no zero-form constraints on-shell. Two examples thereof are a twisting of {C}[{{({{{Z}}2})}3}] that yields the original model, and the Clifford algebra C{{\\ell}2n} which provides an FCS formulation of the bosonic Konstein-Vasiliev model with gauge algebra hu≤ft({{4}n-1},0\\right) .

  6. Flat coordinates for Saito Frobenius manifolds and string theory

    NASA Astrophysics Data System (ADS)

    Belavin, A. A.; Gepner, D.; Kononov, Ya. A.

    2016-12-01

    We investigate the connection between the models of topological conformal theory and noncritical string theory with Saito Frobenius manifolds. For this, we propose a new direct way to calculate the flat coordinates using the integral representation for solutions of the Gauss-Manin system connected with a given Saito Frobenius manifold. We present explicit calculations in the case of a singularity of type A n . We also discuss a possible generalization of our proposed approach to SU( N) k /( SU( N) k+1 × U(1)) Kazama-Suzuki theories. We prove a theorem that the potential connected with these models is an isolated singularity, which is a condition for the Frobenius manifold structure to emerge on its deformation manifold. This fact allows using the Dijkgraaf-Verlinde-Verlinde approach to solve similar Kazama-Suzuki models.

  7. Analysis of Quadratic Diophantine Equations with Fibonacci Number Solutions

    ERIC Educational Resources Information Center

    Leyendekkers, J. V.; Shannon, A. G.

    2004-01-01

    An analysis is made of the role of Fibonacci numbers in some quadratic Diophantine equations. A general solution is obtained for finding factors in sums of Fibonacci numbers. Interpretation of the results is facilitated by the use of a modular ring which also permits extension of the analysis.

  8. ON FROBENIUS PAIRS OF THE FORM (F\\leftthreetimes V,\\, V)

    NASA Astrophysics Data System (ADS)

    Shunkov, V. P.

    1991-02-01

    A nonsimplicity test for groups is obtained which is connected with certain Frobenius pairs. In the case of finite groups it is a natural complement to Glauberman's familiar Z^*-theorem.Bibliography: 10 titles.

  9. Frobenius-norm-based measures of quantum coherence and asymmetry

    PubMed Central

    Yao, Yao; Dong, G. H.; Xiao, Xing; Sun, C. P.

    2016-01-01

    We formulate the Frobenius-norm-based measures for quantum coherence and asymmetry respectively. In contrast to the resource theory of coherence and asymmetry, we construct a natural measure of quantum coherence inspired from optical coherence theory while the group theoretical approach is employed to quantify the asymmetry of quantum states. Besides their simple structures and explicit physical meanings, we observe that these quantities are intimately related to the purity (or linear entropy) of the corresponding quantum states. Remarkably, we demonstrate that the proposed coherence quantifier is not only a measure of mixedness, but also an intrinsic (basis-independent) quantification of quantum coherence contained in quantum states, which can also be viewed as a normalized version of Brukner-Zeilinger invariant information. In our context, the asymmetry of N-qubit quantum systems is considered under local independent and collective transformations. In- triguingly, it is illustrated that the collective effect has a significant impact on the asymmetry measure, and quantum correlation between subsystems plays a non-negligible role in this circumstance. PMID:27558009

  10. Frobenius-norm-based measures of quantum coherence and asymmetry

    NASA Astrophysics Data System (ADS)

    Yao, Yao; Dong, G. H.; Xiao, Xing; Sun, C. P.

    2016-08-01

    We formulate the Frobenius-norm-based measures for quantum coherence and asymmetry respectively. In contrast to the resource theory of coherence and asymmetry, we construct a natural measure of quantum coherence inspired from optical coherence theory while the group theoretical approach is employed to quantify the asymmetry of quantum states. Besides their simple structures and explicit physical meanings, we observe that these quantities are intimately related to the purity (or linear entropy) of the corresponding quantum states. Remarkably, we demonstrate that the proposed coherence quantifier is not only a measure of mixedness, but also an intrinsic (basis-independent) quantification of quantum coherence contained in quantum states, which can also be viewed as a normalized version of Brukner-Zeilinger invariant information. In our context, the asymmetry of N-qubit quantum systems is considered under local independent and collective transformations. In- triguingly, it is illustrated that the collective effect has a significant impact on the asymmetry measure, and quantum correlation between subsystems plays a non-negligible role in this circumstance.

  11. Identities for Apostol-type Frobenius-Euler polynomials resulting from the study of a nonlinear operator

    NASA Astrophysics Data System (ADS)

    Bayad, A.; Kim, T.

    2016-04-01

    We introduce a special nonlinear differential operator and, using its properties, reduce higher-order Frobenius-Euler Apostol-type polynomials to a finite series of first-order Apostol-type Frobenius-Euler polynomials and Stirling numbers. Interesting identities are established.

  12. Lepton mixing, residual symmetries, and trigonometric Diophantine equations

    NASA Astrophysics Data System (ADS)

    Hu, Bo

    2014-10-01

    In this paper, we study residual symmetries in the lepton sector. Our first concern is the symmetry of the charged lepton mass matrix in the basis where the Majorana neutrino mass matrix is diagonal, which is strongly constrained by the requirement that the symmetry group generated by residual symmetries is finite. In a recent work, R. M. Fonseca and W. Grimus found that there exists a set of constraint equations that can be completely solved, which is essential in their approach to the classification of lepton mixing matrices that are fully determined by residual symmetries. In this paper, a method to handle trigonometric Diophantine equations is introduced. We will show that the constraint equations found by Fonseca and Grimus can also be solved by this method. Detailed derivation and discussion will be presented in a self-contained way. In addition, we will also show that, in the case where residual symmetries satisfy a reality condition, this method can be used to solve the equation constraining parameters in the symmetry assignment that controls the group structure generated by residual symmetries and is directly related to mixing matrix elements.

  13. Diophantine equations, Platonic solids, McKay correspondence, equivelar maps and Vogel's universality

    NASA Astrophysics Data System (ADS)

    Khudaverdian, H. M.; Mkrtchyan, R. L.

    2017-04-01

    We notice that one of the Diophantine equations, knm = 2 kn + 2 km + 2 nm, arising in the universality originated Diophantine classification of simple Lie algebras, has interesting interpretations for two different sets of signs of variables. In both cases it describes ;regular polyhedra; with k edges in each vertex, n edges of each face, with total number of edges | m |, and Euler characteristics χ = ± 2. In the case of negative m this equation corresponds to χ = 2 and describes true regular polyhedra, Platonic solids. The case with positive m corresponds to Euler characteristic χ = - 2 and describes the so called equivelar maps (charts) on the surface of genus 2. In the former case there are two routes from Platonic solids to simple Lie algebras-abovementioned Diophantine classification and McKay correspondence. We compare them for all solutions of this type, and find coincidence in the case of icosahedron (dodecahedron), corresponding to E8 algebra. In the case of positive k, n and m we obtain in this way the interpretation of (some of) the mysterious solutions (Y-objects), appearing in the Diophantine classification and having some similarities with simple Lie algebras.

  14. Bounds for departure from normality and the Frobenius norm of matrix eigenvalues

    SciTech Connect

    Lee, S.L.

    1994-12-01

    New lower and upper bounds for the departure from normality and the Frobenius norm of the eigenvalues of a matrix axe given. The significant properties of these bounds axe also described. For example, the upper bound for matrix eigenvalues improves upon the one derived by Kress, de Vries and Wegmann in [Lin. Alg. Appl., 8 (1974), pp. 109-120]. The upper bound for departure from normality is sharp for any matrix whose eigenvalues are collinear in the complex plane. Moreover, the latter formula is a practical estimate that costs (at most) 2m multiplications, where m is the number of nonzeros in the matrix. In terms of applications, the results can be used to bound from above the sensitivity of eigenvalues to matrix perturbations or bound from below the condition number of the eigenbasis of a matrix.

  15. Dynamics of a Skew Tent Map in the Nonlinear Frobenius-Perron Equation

    NASA Astrophysics Data System (ADS)

    Katsuragi, Daisuke

    Return maps of the mean field in globally coupled map lattices (GCML) with a large system size were compared with those at the limit in a large system size. We adopted a nonlinear Frobenius-Perron equation (NFPE) for the limit in the large system size, and used a skew tent map as a chaotic map to simplify calculations in the NFPE. The return maps of the mean field for direct numerical calculations in the GCML usually fluctuate from those for numerical calculations in the NFPE. However, at some coupling strengths, there are totally different return maps between the GCML and the NFPE. We show that this strongly depends on the initial conditions at some coupling strengths.

  16. Ergodic theory and Diophantine approximation for translation surfaces and linear forms

    NASA Astrophysics Data System (ADS)

    Athreya, Jayadev; Parrish, Andrew; Tseng, Jimmy

    2016-08-01

    We derive results on the distribution of directions of saddle connections on translation surfaces using only the Birkhoff ergodic theorem applied to the geodesic flow on the moduli space of translation surfaces. Our techniques, together with an approximation argument, also give an alternative proof of a weak version of a classical theorem in multi-dimensional Diophantine approximation due to Schmidt (1960 Can. J. Math. 12 619-31, 1964 Trans. Am. Math. Soc. 110 493-518). The approximation argument allows us to deduce the Birkhoff genericity of almost all lattices in a certain submanifold of the space of unimodular lattices from the Birkhoff genericity of almost all lattices in the whole space and similarly for the space of affine unimodular lattices.

  17. The local Hurwitz constant and Diophantine approximation on Hecke groups

    NASA Astrophysics Data System (ADS)

    Lehner, J.

    1990-10-01

    Define the Hecke group by {G_q} = < {( {begin{array}{*{20}{c}} 1 & {{⪉mb... ...{array}{*{20}{c}} 0 & { - 1} 1 & 0 } )} rangle , {λ _q} = 2cos π /q , q = 3,4, ldots . We call {G_q}(∞ ) the {G_q} -rationals, and R - {G_q}(∞ ) the {G_q} -irrationals. The problem we treat here is the approximation of {G_q} -irrationals by {G_q} -rationals. Let M(α ) be the upper bound of numbers c for which \\vertα - k/m\\vert < 1/c{m^2} for all {G_q} -irrationals and infinitely many k/m in {G_q}(∞ ) . Set h_q'= {inf _α }M(α ) . We call h_q' the Hurwitz constant for {G_q} . It is known that h_q'= 2 , q even; h_q'= 2{(1 + {(1 - {λ _q}/2)^2})^{1/2}} , q odd. In this paper we prove this result by using {λ _q} -continued fractions, as developed previously by D. Rosen. Write α - frac{{{P_{n - 1}}}}{{{Q_{n - 1}}}} = frac{{{{( - 1)}^{... ...}{\\varepsilon _2} \\cdots {\\varepsilon _n}}}{{{m_{n - 1}}(α )Q_{n - 1}^2}}, where {\\varepsilon _i} = ± 1 and {P_i}/{Q_i} are the convergents of the {λ _q} -continued fraction for α . Then M(α ) = {overline {lim } _n}{m_n}(α ) . We call {m_n}(α ) the local Hurwitz constant. In the final section we prove some results on the local Hurwitz constant. For example (Theorem 4), it is shown that if q is odd and {\\varepsilon _{n + 1}} = {\\varepsilon _{n + 2}} = + 1 , then {m_i} ≥ {(λ _q^2 + 4)^{1/2}} > h_q' for at least one of i = n - 1,n,n + 1 .

  18. Modelling Problem-Solving Situations into Number Theory Tasks: The Route towards Generalisation

    ERIC Educational Resources Information Center

    Papadopoulos, Ioannis; Iatridou, Maria

    2010-01-01

    This paper examines the way two 10th graders cope with a non-standard generalisation problem that involves elementary concepts of number theory (more specifically linear Diophantine equations) in the geometrical context of a rectangle's area. Emphasis is given on how the students' past experience of problem solving (expressed through interplay…

  19. Fourier transforms on Cantor sets: A study in non-Diophantine arithmetic and calculus

    NASA Astrophysics Data System (ADS)

    Aerts, Diederik; Czachor, Marek; Kuna, Maciej

    2016-10-01

    Fractals equipped with intrinsic arithmetic lead to a natural definition of differentiation, integration and complex numbers. Applying the formalism to the problem of a Fourier transform on fractals we show that the resulting transform has all the expected basic properties. As an example we discuss a sawtooth signal on the ternary middle-third Cantor set. The formalism works also for fractals that are not self-similar.

  20. On applications of diophantine approximations

    PubMed Central

    Chudnovsky, G. V.

    1984-01-01

    This paper is devoted to the study of the arithmetic properties of values of G-functions introduced by Siegel [Siegel, C. L. (1929) Abh. Preuss. Akad. Wiss. Phys.-Math. Kl. 1]. One of the main results is a theorem on the linear independence of values of G-functions at rational points close to the origin. In this theorem, no conditions are imposed on the p-adic convergence of a G-function at a generic point. The theorem finally realizes Siegel's program on G-function values outlined in his paper. PMID:16593530

  1. BAROCLINIC INSTABILITY IN THE SOLAR TACHOCLINE. II. THE EADY PROBLEM

    SciTech Connect

    Gilman, Peter A.

    2016-02-20

    We solve the nongeostrophic baroclinic instability problem for the tachocline for a continuous model with a constant vertical rotation gradient (the Eady problem), using power series generated by the Frobenius method. The results confirm and greatly extend those from a previous two-layer model. For effective gravity G independent of height, growth rates and ranges of unstable longitudinal wavenumbers m and latitudes increase with decreasing G. As with the two-layer model, the overshoot tachocline is much more unstable than the radiative tachocline. The e-folding growth times range from as short as 10 days to as long as several years, depending on latitude, G, and wavenumber. For a more realistic effective gravity that decreases linearly from the radiative interior to near zero at the top of the tachocline, we find that only m = 1, 2 modes are unstable, with growth rates somewhat larger than for constant G, with the same value as at the bottom of the tachocline. All results are the same whether we assume that the vertical velocity or the perturbation pressure is zero at the top of the layer; this is a direct consquence of not employing the geostrophic assumption for perturbations. We explain most of the properties of the instability in terms of the Rossby deformation radius. We discuss further improvements in the realism of the model, particularly adding toroidal fields that vary in height, and including latitudinal gradients of both rotation and toroidal fields.

  2. On a Diophantine Equation of Stroeker

    DTIC Science & Technology

    2008-10-27

    Moreover, if N = 3, both points are of order 9 and if N = 9, they are of order 6. 7 Proof. Using Magma [1], for 2 ≤ N ≤ 100, we checked that the...Wieb Bosma, John Cannon, and Catherine Playoust, ‘The Magma alge- bra system. I. The user language‘, J. Symbolic Comput. 24 3-4 (1997), 235-265. [2

  3. Padé approximations and diophantine geometry

    PubMed Central

    Chudnovsky, D. V.; Chudnovsky, G. V.

    1985-01-01

    Using methods of Padé approximations we prove a converse to Eisenstein's theorem on the boundedness of denominators of coefficients in the expansion of an algebraic function, for classes of functions, parametrized by meromorphic functions. This result is applied to the Tate conjecture on the effective description of isogenies for elliptic curves. PMID:16593552

  4. LETTER TO THE EDITOR: Diophantine integrability

    NASA Astrophysics Data System (ADS)

    Halburd, R. G.

    2005-04-01

    The heights of iterates of the discrete Painlevé equations over number fields appear to grow no faster than polynomials while the heights of generic solutions of non-integrable discrete equations grow exponentially. This gives rise to a simple and effective numerical test for the integrability of discrete equations. Numerical evidence and theoretical results are presented. Connections with other tests for integrability and Vojta's dictionary are discussed.

  5. XRF map identification problems based on a PDE electrodeposition model

    NASA Astrophysics Data System (ADS)

    Sgura, Ivonne; Bozzini, Benedetto

    2017-04-01

    In this paper we focus on the following map identification problem (MIP): given a morphochemical reaction–diffusion (RD) PDE system modeling an electrodepostion process, we look for a time t *, belonging to the transient dynamics and a set of parameters \\mathbf{p} , such that the PDE solution, for the morphology h≤ft(x,y,{{t}\\ast};\\mathbf{p}\\right) and for the chemistry θ ≤ft(x,y,{{t}\\ast};\\mathbf{p}\\right) approximates a given experimental map M *. Towards this aim, we introduce a numerical algorithm using singular value decomposition (SVD) and Frobenius norm to give a measure of error distance between experimental maps for h and θ and simulated solutions of the RD-PDE system on a fixed time integration interval. The technique proposed allows quantitative use of microspectroscopy images, such as XRF maps. Specifically, in this work we have modelled the morphology and manganese distributions of nanostructured components of innovative batteries and we have followed their changes resulting from ageing under operating conditions. The availability of quantitative information on space-time evolution of active materials in terms of model parameters will allow dramatic improvements in knowledge-based optimization of battery fabrication and operation.

  6. Problem Solving

    ERIC Educational Resources Information Center

    Kinsella, John J.

    1970-01-01

    Discussed are the nature of a mathematical problem, problem solving in the traditional and modern mathematics programs, problem solving and psychology, research related to problem solving, and teaching problem solving in algebra and geometry. (CT)

  7. Balance Problems

    MedlinePlus

    ... often, it could be a sign of a balance problem. Balance problems can make you feel unsteady or as ... fall-related injuries, such as hip fracture. Some balance problems are due to problems in the inner ...

  8. Balance Problems

    MedlinePlus

    ... version of this page please turn Javascript on. Balance Problems About Balance Problems Have you ever felt dizzy, lightheaded, or ... dizziness problem during the past year. Why Good Balance is Important Having good balance means being able ...

  9. Walking Problems

    MedlinePlus

    ... Parkinson's disease Diseases such as arthritis or multiple sclerosis Vision or balance problems Treatment of walking problems depends on the cause. Physical therapy, surgery, or mobility aids may help.

  10. The Problems of Problem Solving

    ERIC Educational Resources Information Center

    Watson, Charles E.

    1976-01-01

    Discusses some common pitfalls in problem-solving and outlines three basic approaches to successfully identifying problems and their causes. (Available from Business Horizons, School of Business, Indiana University, Bloomington, Indiana 47401; $2.50, single copy) (Author/JG)

  11. Childbirth Problems

    MedlinePlus

    While childbirth usually goes well, complications can happen. They can cause a risk to the mother, baby, or both. Possible complications include Preterm (premature) labor, when labor starts before 37 completed weeks of pregnancy Problems with the umbilical cord Problems with ...

  12. Speech Problems

    MedlinePlus

    ... and the respiratory system . The ability to understand language and produce speech is coordinated by the brain. So a person with brain damage from an accident, stroke, or birth defect may have speech and language problems. Some people with speech problems, particularly articulation ...

  13. Popular Problems

    ERIC Educational Resources Information Center

    Skovhus, Randi Boelskifte; Thomsen, Rie

    2017-01-01

    This article introduces a method to critical reviews and explores the ways in which problems have been formulated in knowledge production on career guidance in Denmark over a 10-year period from 2004 to 2014. The method draws upon the work of Bacchi focussing on the "What's the problem represented to be" (WPR) approach. Forty-nine…

  14. Parking Problem

    ERIC Educational Resources Information Center

    Foster, Colin

    2012-01-01

    This is the story of a real problem, not a problem that is contrived, or invented for the convenience of the appropriate planning tool. This activity by a group of students, defined simply as "8FN", might be likened to an "end of term concert". If you just happened to be a delegate at the ATM Conference 2003 you might remember…

  15. Hopf and Frobenius algebras in conformal field theory

    NASA Astrophysics Data System (ADS)

    Singh, Sukreet

    With the current rapid depletion of non-renewable resources to generate power, energy conservation and on site generation have become the most critical aspects of the equation. Buildings should be so designed or retrofitted in order to generate its own electricity and cater to its own demand. This thesis looks as the ways in which we can do a post occupancy analysis of an existing institutional building of about 95,000 square feet that was built in 1960's in order to reduce usage and approach a Zero Net Energy goal. This case study building is Von Kleinsmid Centre (VKC) which is located at the heart of USC (University of Southern California). It is challenging to retrofit an existing institutional building because of its complexity and make it achieve a 'Zero Net Energy' goal. All the roadblocks, real life delays, software limitations that had to be overcome to achieve this result are explained in this thesis. The Zero Net Energy goal was achieved by calibrating energy model to the utility data of the building, providing various energy efficiency measures and generating on-site electricity.

  16. Sleep Problems

    MedlinePlus

    ... For Consumers Consumer Information by Audience For Women Sleep Problems Share Tweet Linkedin Pin it More sharing ... PDF 474KB) En Español Medicines to Help You Sleep Tips for Better Sleep Basic Facts about Sleep ...

  17. Thyroid Problems

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  18. Breathing Problems

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  19. Kidney Problems

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  20. Sexual Problems

    MedlinePlus

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  1. Nipple problems

    MedlinePlus

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  2. Speech Problems

    MedlinePlus

    ... thinking, but it becomes disorganized as they're speaking. So, someone who clutters may speak in bursts ... refuse to wait patiently for them to finish speaking. If you have a speech problem, it's fine ...

  3. The temporal prior in bioelectromagnetic source imaging problems.

    PubMed

    Greensite, Fred

    2003-10-01

    The multiplicity of temporal priors proposed for regularization of the bioelectromagnetic source imaging problems [e.g., the inverse electrocardiogram (ECG) and inverse electroencephalogram (EEG) problems], is discordant with the fact that fundamental statistical principles sharply limit the choice. Thus, our objective is to derive the form of the prior consistent with the general unavailability of temporal constraints. Writing linear formulations of the inverse ECG and inverse EEG problems as H = FG + N (where the ith columns of matrices H, G, and N, are data, signal, and noise vectors at time step i, and F is the transfer matrix), and using the noninformative principle that features of the spatiotemporal prior not supplied a posteriori should be invariant under temporal transformations, we show that the implied spatiotemporal signal autocovariance matrix (of the vector formed by the entries of G) is given in block matrix form [equation in text] where Cg is a matrix of unit trace proportional to the autocovariance matrix of any column of G (representing supplied information regarding the spatial prior), epsilon[.] denotes expectation, superscript ' indicates transpose, [symbol in text] is the Kronecker product, [symbol in text] is Frobenius norm, and the "matrix scalar product" [symbol in text] indicates the inner product of the two vectors formed by the entries of the two adjacent matrices (i.e., A [symbol in text] B [triple bond] trace[A'B]). This result eliminates some uncertainties and ambiguities that have characterized spatiotemporal regularization methods--including eight methods previously introduced in this transactions. Ultimately, the result derives from an implied symmetry principle under which the form of a nontrivial noninformative temporal component of the prior can be identified. Among other things, separability of the spatiotemporal prior in terms of the above Kronecker product can be thought of as the expression of the lack of "entanglement" of

  4. Heat Problems.

    ERIC Educational Resources Information Center

    Connors, G. Patrick

    Heat problems and heat cramps related to jogging can be caused by fluid imbalances, medications, dietary insufficiency, vomiting or diarrhea, among other factors. If the condition keeps reoccurring, the advice of a physician should be sought. Some preventive measures that can be taken include: (1) running during the cooler hours of the day; (2)…

  5. Puzzles & Problems.

    ERIC Educational Resources Information Center

    Murphy, Pat, Ed.

    1993-01-01

    "Exploring" is a magazine of science, art, and human perception, produced by Exploratorium in collaboration with other participating museums. This issue focuses on puzzles and problem solving. Brain teasers, puzzles, and the strategies for solving them are included. Features include: (1) "Homework Assignment #3" (Paul Doherty);…

  6. The simplest problem in the collective dynamics of neural networks: is synchrony stable?

    NASA Astrophysics Data System (ADS)

    Timme, Marc; Wolf, Fred

    2008-07-01

    For spiking neural networks we consider the stability problem of global synchrony, arguably the simplest non-trivial collective dynamics in such networks. We find that even this simplest dynamical problem—local stability of synchrony—is non-trivial to solve and requires novel methods for its solution. In particular, the discrete mode of pulsed communication together with the complicated connectivity of neural interaction networks requires a non-standard approach. The dynamics in the vicinity of the synchronous state is determined by a multitude of linear operators, in contrast to a single stability matrix in conventional linear stability theory. This unusual property qualitatively depends on network topology and may be neglected for globally coupled homogeneous networks. For generic networks, however, the number of operators increases exponentially with the size of the network. We present methods to treat this multi-operator problem exactly. First, based on the Gershgorin and Perron-Frobenius theorems, we derive bounds on the eigenvalues that provide important information about the synchronization process but are not sufficient to establish the asymptotic stability or instability of the synchronous state. We then present a complete analysis of asymptotic stability for topologically strongly connected networks using simple graph-theoretical considerations. For inhibitory interactions between dissipative (leaky) oscillatory neurons the synchronous state is stable, independent of the parameters and the network connectivity. These results indicate that pulse-like interactions play a profound role in network dynamical systems, and in particular in the dynamics of biological synchronization, unless the coupling is homogeneous and all-to-all. The concepts introduced here are expected to also facilitate the exact analysis of more complicated dynamical network states, for instance the irregular balanced activity in cortical neural networks.

  7. Helicopter problems

    NASA Technical Reports Server (NTRS)

    Kussner, H G

    1937-01-01

    The present report deals with a number of the main problems requiring solution in the development of helicopters and concerning the lift, flying performance, stability, and drive. A complete solution is given for the stability of the helicopter with rigid blades and control surfaces. With a view to making a direct-lift propeller sufficient without the addition of auxiliary propellers, the "flapping drive" is assessed and its efficiency calculated.

  8. Hierarchi problem

    NASA Astrophysics Data System (ADS)

    Rubin, Sergey G.

    2016-02-01

    The way to solve the hierarchy problem based on multidimensional gravity is discussed. Various metrics of deformed extra space are produced at the Planck scale. It is shown that the Higgs vacuum value depends on a metric of extra space and hence their different numerical values are realized in various universes. An interval of the Higgs vacuum values is proved include zero value. Our universe belongs to a set of universes the vacuum values of which are close to zero

  9. Throat Problems (Symptom Checker)

    MedlinePlus

    ... BMI Calculator myhealthfinder Immunization Schedules Nutrient Shortfall Questionnaire Throat ProblemsThroat pain and mouth sores, along with other ... Children Shoulder Problems Skin Rashes & Other Skin Problems Throat Problems Tooth Problems Urination Problems Back to Symptoms ...

  10. Preventing Diabetes Problems

    MedlinePlus

    ... Other Dental Problems Diabetes & Sexual & Urologic Problems Preventing Diabetes Problems View or Print All Sections Heart Disease & ... prevent or delay sexual and urologic problems. Depression & Diabetes Depression is common among people with a chronic, ...

  11. Problem: Heart Valve Stenosis

    MedlinePlus

    ... valve . Learn about the different types of stenosis: Aortic stenosis Tricuspid stenosis Pulmonary stenosis Mitral stenosis Outlook for ... Disease "Innocent" Heart Murmur Problem: Valve Stenosis - Problem: Aortic Valve Stenosis - Problem: Mitral Valve Stenosis - Problem: Tricuspid Valve Stenosis - ...

  12. Problems with "n"th-Term Problems

    ERIC Educational Resources Information Center

    Matteson, Shirley M.

    2010-01-01

    An nth-term problem involves a sequence. Students must determine which expression will allow them to calculate the nth position of the sequence. To solve such problems, students are to find "a rule that determines the number of elements in a step from the step number." These types of problems help students develop concepts of functions, variables,…

  13. Class and Home Problems: Optimization Problems

    ERIC Educational Resources Information Center

    Anderson, Brian J.; Hissam, Robin S.; Shaeiwitz, Joseph A.; Turton, Richard

    2011-01-01

    Optimization problems suitable for all levels of chemical engineering students are available. These problems do not require advanced mathematical techniques, since they can be solved using typical software used by students and practitioners. The method used to solve these problems forces students to understand the trends for the different terms…

  14. Group problems in problem-based learning.

    PubMed

    Hendry, Graham D; Ryan, Greg; Harris, Jennifer

    2003-11-01

    Successful small-group learning in problem-based learning (PBL) educational programmes relies on functional group processes. However, there has been limited research on PBL group problems, and no studies have been conducted on problems as perceived by both students and tutors in the same educational context. The authors investigated PBL group problems in a graduate-entry medical programme, and report the most common group problems, and those that hinder students' learning the most. The possible causes of individual quietness and dominant behaviour, and potential influences that group problems may have on the tutorial process are summarized in an exploratory model of PBL group dysfunction that could be used to guide further research. Specifically, there is a need for further evidence on which to base guidelines for tutors and students to effectively manage group problems.

  15. Problems with Smell

    MedlinePlus

    ... this page please turn Javascript on. Problems with Smell About Problems with Smell Our sense of smell helps us enjoy life. ... sec Click to watch this video Aging and Smell Loss Problems with smell increase as people get ...

  16. The Chicken Problem.

    ERIC Educational Resources Information Center

    Reeves, Charles A.

    2000-01-01

    Uses the chicken problem for sixth grade students to scratch the surface of systems of equations using intuitive approaches. Provides students responses to the problem and suggests similar problems for extensions. (ASK)

  17. Problem? "No Problem!" Solving Technical Contradictions

    ERIC Educational Resources Information Center

    Kutz, K. Scott; Stefan, Victor

    2007-01-01

    TRIZ (pronounced TREES), the Russian acronym for the theory of inventive problem solving, enables a person to focus his attention on finding genuine, potential solutions in contrast to searching for ideas that "may" work through a happenstance way. It is a patent database-backed methodology that helps to reduce time spent on the problem,…

  18. PROBLEMS OF MIGRANT LABOR.

    ERIC Educational Resources Information Center

    WALLS, FOREST

    PRESENT MIGRANT LABOR PROBLEMS AND SOLUTIONS WHICH HAVE BEEN PROPOSED ARE PRESENTED. THE FIRST PROBLEM AREA IS PROVIDING EDUCATION FOR MIGRANT CHILDREN. THIS IS HINDERED BY THE PROBLEM OF SECURING COMPLIANCE WITH MINIMUM EDUCATION LAWS AND BY LAWS PROHIBITING EMPLOYMENT OF CHILDREN DURING SCHOOL HOURS. A SECOND PROBLEM AREA IS THAT OF CHILD LABOR.…

  19. Quadratic eigenvalue problems.

    SciTech Connect

    Walsh, Timothy Francis; Day, David Minot

    2007-04-01

    In this report we will describe some nonlinear eigenvalue problems that arise in the areas of solid mechanics, acoustics, and coupled structural acoustics. We will focus mostly on quadratic eigenvalue problems, which are a special case of nonlinear eigenvalue problems. Algorithms for solving the quadratic eigenvalue problem will be presented, along with some example calculations.

  20. The Algorithm Selection Problem

    NASA Technical Reports Server (NTRS)

    Minton, Steve; Allen, John; Deiss, Ron (Technical Monitor)

    1994-01-01

    Work on NP-hard problems has shown that many instances of these theoretically computationally difficult problems are quite easy. The field has also shown that choosing the right algorithm for the problem can have a profound effect on the time needed to find a solution. However, to date there has been little work showing how to select the right algorithm for solving any particular problem. The paper refers to this as the algorithm selection problem. It describes some of the aspects that make this problem difficult, as well as proposes a technique for addressing it.

  1. [The mind -- body problem].

    PubMed

    Pérez, Diana I

    2005-01-01

    In this paper I present, in the first place, two of the main problems in the philosophy of mind: 1) the problem of the criteria of the mental, and 2) the problem of the relationship between the mental and the physical. In the last part, I mention two problems highly discussed nowadays which, in my view, will produce the most important advance in the knowledge of our minds in the next decades: the problem of consciousness and its neural basis, and the problem of the origin and development of a theory of mind.

  2. Puzzles Pastimes Problems.

    ERIC Educational Resources Information Center

    Eperson, D. B.

    1991-01-01

    This section includes eight problems to which the journal invites readers to respond. Problem topics include angles in alternate segments, pentominoes, a new triangle of numbers, cricket scores, symmetrical pentagons, inequalities, a pythagorean dissection, and magic squares. (MDH)

  3. IT Problem Management

    NASA Video Gallery

    IT Problem Management – process responsible for managing Lifecycle of all IT problems. The primary objective is to prevent incidents from occurring and to minimize impact of incidents that cannot...

  4. The molecular matching problem

    NASA Technical Reports Server (NTRS)

    Kincaid, Rex K.

    1993-01-01

    Molecular chemistry contains many difficult optimization problems that have begun to attract the attention of optimizers in the Operations Research community. Problems including protein folding, molecular conformation, molecular similarity, and molecular matching have been addressed. Minimum energy conformations for simple molecular structures such as water clusters, Lennard-Jones microclusters, and short polypeptides have dominated the literature to date. However, a variety of interesting problems exist and we focus here on a molecular structure matching (MSM) problem.

  5. Problem Solving by Design

    ERIC Educational Resources Information Center

    Capobianco, Brenda M.; Tyrie, Nancy

    2009-01-01

    In a unique school-university partnership, methods students collaborated with fifth graders to use the engineering design process to build their problem-solving skills. By placing the problem in the context of a client having particular needs, the problem took on a real-world appeal that students found intriguing and inviting. In this article, the…

  6. Assessment Problems in Reading.

    ERIC Educational Resources Information Center

    MacGinitie, Walter H., Ed.

    The papers in this volume deal with a range of assessment problems in reading. The first paper, by Karlin, introduces the general problem of using assessment procedures to guide teaching. The next six papers deal with various aspects of this general problem. Otto discusses the distinction between norm-referenced, standardized achievement tests and…

  7. Problems of Indian Children.

    ERIC Educational Resources Information Center

    Linton, Marigold

    Previous approaches to the learning problems of American Indian children are viewed as inadequate. An alternative is suggested which emphasizes the problem solution strategies which these children bring to the school situation. Solutions were analyzed in terms of: (1) their probability; (2) their efficiency at permitting a present problem to be…

  8. Techniques of Problem Solving.

    ERIC Educational Resources Information Center

    Krantz, Steven G.

    The purpose of this book is to teach the basic principles of problem solving in both mathematical and non-mathematical problems. The major components of the book consist of learning to translate verbal discussion into analytical data, learning problem solving methods for attacking collections of analytical questions or data, and building a…

  9. Exploratory Problems in Mathematics.

    ERIC Educational Resources Information Center

    Stevenson, Frederick W.

    This book attempts to introduce students to the creative aspects of mathematics through exploratory problems. The introduction presents the criteria for the selection of the problems in the book. Criteria indicate that problems should: be immediately attractive, require data to be generated or gathered, appeal to students from junior high school…

  10. Problems of nonlinear deformation

    NASA Astrophysics Data System (ADS)

    Grigoliuk, E. I.; Shalashilin, V. I.

    A method of continuing the solution is discussed with respect to a parameter for a certain class of nonlinear problems in solid mechanics. Modifications of the method are developed in order to implement a unified continuation process at regular and limit points in the set of solutions, with extensions to nonlinear boundary value problems. Algorithms are developed for solving large deflection problems of elastic arches and large axisymmetric deflection problems for shells of revolution. In particular, the algorithms are used for the analysis of large deflections of circular arches and toroidal shells. Examples of natural vibration and stability problems for parallelograms and trapezoidal membranes and panels are given.

  11. Genital Problems in Infants (Female)

    MedlinePlus

    ... Schedules Nutrient Shortfall Questionnaire Genital Problems in Infants (Female)Any deformity or change in the genitals is ... and Children Foot Problems Genital Problems in Infants (Female) Genital Problems in Infants (Male) Genital Problems in ...

  12. Matrix interdiction problem

    SciTech Connect

    Pan, Feng; Kasiviswanathan, Shiva

    2010-01-01

    In the matrix interdiction problem, a real-valued matrix and an integer k is given. The objective is to remove k columns such that the sum over all rows of the maximum entry in each row is minimized. This combinatorial problem is closely related to bipartite network interdiction problem which can be applied to prioritize the border checkpoints in order to minimize the probability that an adversary can successfully cross the border. After introducing the matrix interdiction problem, we will prove the problem is NP-hard, and even NP-hard to approximate with an additive n{gamma} factor for a fixed constant {gamma}. We also present an algorithm for this problem that achieves a factor of (n-k) mUltiplicative approximation ratio.

  13. Known TCP Implementation Problems

    NASA Technical Reports Server (NTRS)

    Paxson, Vern (Editor); Allman, Mark; Dawson, Scott; Fenner, William; Griner, Jim; Heavens, Ian; Lahey, K.; Semke, J.; Volz, B.

    1999-01-01

    This memo catalogs a number of known TCP implementation problems. The goal in doing so is to improve conditions in the existing Internet by enhancing the quality of current TCP/IP implementations. It is hoped that both performance and correctness issues can be resolved by making implementors aware of the problems and their solutions. In the long term, it is hoped that this will provide a reduction in unnecessary traffic on the network, the rate of connection failures due to protocol errors, and load on network servers due to time spent processing both unsuccessful connections and retransmitted data. This will help to ensure the stability of the global Internet. Each problem is defined as follows: Name of Problem The name associated with the problem. In this memo, the name is given as a subsection heading. Classification one or more problem categories for which the problem is classified: "congestion control", "performance", "reliability", "resource management". Description A definition of the problem, succinct but including necessary background material. Significance A brief summary of the sorts of environments for which the problem is significant.

  14. Tactical missile turbulence problems

    NASA Technical Reports Server (NTRS)

    Dickson, Richard E.

    1987-01-01

    Of particular interest is atmospheric turbulence in the atmospheric boundary layer, since this affects both the launch and terminal phase of flight, and the total flight for direct fire systems. Brief discussions are presented on rocket artillery boost wind problems, mean wind correction, turbulent boost wind correction, the Dynamically Aimed Free Flight Rocket (DAFFR) wind filter, the DAFFR test, and rocket wake turbulence problems. It is concluded that many of the turbulence problems of rockets and missiles are common to those of aircraft, such as structural loading and control system design. However, these problems have not been solved at this time.

  15. Problem-Based Learning

    ERIC Educational Resources Information Center

    Allen, Deborah E.; Donham, Richard S.; Bernhardt, Stephen A.

    2011-01-01

    In problem-based learning (PBL), students working in collaborative groups learn by resolving complex, realistic problems under the guidance of faculty. There is some evidence of PBL effectiveness in medical school settings where it began, and there are numerous accounts of PBL implementation in various undergraduate contexts, replete with…

  16. Problem Solving Techniques Seminar.

    ERIC Educational Resources Information Center

    Massachusetts Career Development Inst., Springfield.

    This booklet is one of six texts from a workplace literacy curriculum designed to assist learners in facing the increased demands of the workplace. Six problem-solving techniques are developed in the booklet to assist individuals and groups in making better decisions: problem identification, data gathering, data analysis, solution analysis,…

  17. Problems in baryon spectroscopy

    SciTech Connect

    Capstick, S.

    1994-04-01

    Current issues and problems in the physics of ground- and excited-state baryons are considered, and are classified into those which should be resolved by CEBAF in its present form, and those which may require CEBAF to undergo an energy upgrade to 8 GeV or more. Recent theoretical developments designed to address these problems are outlined.

  18. TOCFL: Problems and Guidelines.

    ERIC Educational Resources Information Center

    Weiping, Wu

    Problems in the testing of Chinese as a foreign language (CFL) are examined, focusing on proficiency testing needs and test standardization. Particular attention is paid to listening and reading assessment. The first part of the discussion looks at specific problems with five existing proficiency tests, including such aspects as inadequacy of the…

  19. Stabilization of Kepler's problem

    NASA Technical Reports Server (NTRS)

    Stokes, A.

    1977-01-01

    A regularization of Kepler's problem due to Moser (1970) is used to stabilize the equations of motion. In other words, a particular solution of Kepler's problem is imbedded in a Liapunov stable system. Perturbations can be introduced into the stabilized equations.

  20. Teaching through Problem Solving

    ERIC Educational Resources Information Center

    Fi, Cos D.; Degner, Katherine M.

    2012-01-01

    Teaching through Problem Solving (TtPS) is an effective way to teach mathematics "for" understanding. It also provides students with a way to learn mathematics "with" understanding. In this article, the authors present a definition of what it means to teach through problem solving. They also describe a professional development vignette that…

  1. A Stochastic Employment Problem

    ERIC Educational Resources Information Center

    Wu, Teng

    2013-01-01

    The Stochastic Employment Problem(SEP) is a variation of the Stochastic Assignment Problem which analyzes the scenario that one assigns balls into boxes. Balls arrive sequentially with each one having a binary vector X = (X[subscript 1], X[subscript 2],...,X[subscript n]) attached, with the interpretation being that if X[subscript i] = 1 the ball…

  2. Student-Posed Problems

    NASA Astrophysics Data System (ADS)

    Harper, Kathleen A.; Etkina, Eugenia

    2002-10-01

    As part of weekly reports,1 structured journals in which students answer three standard questions each week, they respond to the prompt, If I were the instructor, what questions would I ask or problems assign to determine if my students understood the material? An initial analysis of the results shows that some student-generated problems indicate fundamental misunderstandings of basic physical concepts. A further investigation explores the relevance of the problems to the week's material, whether the problems are solvable, and the type of problems (conceptual or calculation-based) written. Also, possible links between various characteristics of the problems and conceptual achievement are being explored. The results of this study spark many more questions for further work. A summary of current findings will be presented, along with its relationship to previous work concerning problem posing.2 1Etkina, E. Weekly Reports;A Two-Way Feedback Tool, Science Education, 84, 594-605 (2000). 2Mestre, J.P., Probing Adults Conceptual Understanding and Transfer of Learning Via Problem Posing, Journal of Applied Developmental Psychology, 23, 9-50 (2002).

  3. Inquiry and Problem Solving.

    ERIC Educational Resources Information Center

    Thorson, Annette, Ed.

    1999-01-01

    This issue of ENC Focus focuses on the topic of inquiry and problem solving. Featured articles include: (1) "Inquiry in the Everyday World of Schools" (Ronald D. Anderson); (2) "In the Cascade Reservoir Restoration Project Students Tackle Real-World Problems" (Clint Kennedy with Advanced Biology Students from Cascade High…

  4. California's Water Problems.

    ERIC Educational Resources Information Center

    Wheatley, Judy; Sudman, Rita Schmidt, Ed.

    This packet of instructional materials is designed to give social science students in grades 6-9 a first-hand experience in working out solutions to real-life problems involving the management of California's water. Students work in groups on one of three problems presented in the packet: (1) the management of the Sacramento-San Joaquin Delta that…

  5. Problem Solving in Electricity.

    ERIC Educational Resources Information Center

    Caillot, Michel; Chalouhi, Elias

    Two studies were conducted to describe how students perform direct current (D-C) circuit problems. It was hypothesized that problem solving in the electricity domain depends largely on good visual processing of the circuit diagram and that this processing depends on the ability to recognize when two or more electrical components are in series or…

  6. Strategies for Problem Solving.

    ERIC Educational Resources Information Center

    Karmos, Joseph S.; Karmos, Ann H.

    Problem-solving skills are becoming increasingly important in the workplace, and more schools are including them in the curriculum. Knowledge of problem solving will be critical to a work force that is dealing with advanced technology, yet many students have yet to master these skills. Based on this premise, this guide attempts to show how…

  7. The Problems of Dissection.

    ERIC Educational Resources Information Center

    Davis, Pat

    1997-01-01

    Describes some problems of classroom dissection including the cruelty that animals destined for the laboratory suffer. Discusses the multilevel approach that the National Anti-Vivisection Society (NAVS) has developed to address the problems of animal dissection such as offering a dissection hotline, exhibiting at science teacher conferences, and…

  8. GREECE--SELECTED PROBLEMS.

    ERIC Educational Resources Information Center

    MARTONFFY, ANDREA PONTECORVO; AND OTHERS

    A CURRICULUM GUIDE IS PRESENTED FOR A 10-WEEK STUDY OF ANCIENT GREEK CIVILIZATION AT THE 10TH-GRADE LEVEL. TEACHING MATERIALS FOR THE UNIT INCLUDE (1) PRIMARY AND SECONDARY SOURCES DEALING WITH THE PERIOD FROM THE BRONZE AGE THROUGH THE HELLENISTIC PERIOD, (2) GEOGRAPHY PROBLEMS, AND (3) CULTURAL MODEL PROBLEM EXERCISES. THOSE CONCEPTS WITH WHICH…

  9. Current Social Problem Novels.

    ERIC Educational Resources Information Center

    Kenney, Donald J.

    This review of social problem novels for young adults opens with a brief background of the genre, then lists the dominant themes of social problem fiction and nonfiction novels that have been published in the last two years, such as alcoholism, alienation, death, growing up and self-awarness, drugs, and divorce. Other themes mentioned are…

  10. Problems Facing Rural Schools.

    ERIC Educational Resources Information Center

    Stewart, C. E.; And Others

    Problems facing rural Scottish schools range from short term consideration of daily operation to long term consideration of organizational alternatives. Addressed specifically, such problems include consideration of: (1) liaison between a secondary school and its feeder primary schools; (2) preservice teacher training for work in small, isolated…

  11. The Guderley problem revisited

    SciTech Connect

    Ramsey, Scott D; Kamm, James R; Bolstad, John H

    2009-01-01

    The self-similar converging-diverging shock wave problem introduced by Guderley in 1942 has been the source of numerous investigations since its publication. In this paper, we review the simplifications and group invariance properties that lead to a self-similar formulation of this problem from the compressible flow equations for a polytropic gas. The complete solution to the self-similar problem reduces to two coupled nonlinear eigenvalue problems: the eigenvalue of the first is the so-called similarity exponent for the converging flow, and that of the second is a trajectory multiplier for the diverging regime. We provide a clear exposition concerning the reflected shock configuration. Additionally, we introduce a new approximation for the similarity exponent, which we compare with other estimates and numerically computed values. Lastly, we use the Guderley problem as the basis of a quantitative verification analysis of a cell-centered, finite volume, Eulerian compressible flow algorithm.

  12. Environmental problem solving

    SciTech Connect

    Miller, A.

    1999-06-01

    Human influences create both environmental problems and barriers to effective policy aimed at addressing those problems. In effect, environmental managers manage people as much as they manage the environment. Therefore, they must gain an understanding of the psychological and sociopolitical dimensions of environmental problems that they are attempting to resolve. The author reappraises conventional analyses of environmental problems using lessons from the psychosocial disciplines. The author combines the disciplines of ecology, political sociology and psychology to produce a more adaptive approach to problem-solving that is specifically geared toward the environmental field. Numerous case studies demonstrate the practical application of theory in a way that is useful to technical and scientific professionals as well as to policymakers and planners.

  13. Problem Solving and Learning

    NASA Astrophysics Data System (ADS)

    Singh, Chandralekha

    2009-07-01

    One finding of cognitive research is that people do not automatically acquire usable knowledge by spending lots of time on task. Because students' knowledge hierarchy is more fragmented, "knowledge chunks" are smaller than those of experts. The limited capacity of short term memory makes the cognitive load high during problem solving tasks, leaving few cognitive resources available for meta-cognition. The abstract nature of the laws of physics and the chain of reasoning required to draw meaningful inferences makes these issues critical. In order to help students, it is crucial to consider the difficulty of a problem from the perspective of students. We are developing and evaluating interactive problem-solving tutorials to help students in the introductory physics courses learn effective problem-solving strategies while solidifying physics concepts. The self-paced tutorials can provide guidance and support for a variety of problem solving techniques, and opportunity for knowledge and skill acquisition.

  14. Astronauts' menu problem.

    NASA Technical Reports Server (NTRS)

    Lesso, W. G.; Kenyon, E.

    1972-01-01

    Consideration of the problems involved in choosing appropriate menus for astronauts carrying out SKYLAB missions lasting up to eight weeks. The problem of planning balanced menus on the basis of prepackaged food items within limitations on the intake of calories, protein, and certain elements is noted, as well as a number of other restrictions of both physical and arbitrary nature. The tailoring of a set of menus for each astronaut on the basis of subjective rankings of each food by the astronaut in terms of a 'measure of pleasure' is described, and a computer solution to this problem by means of a mixed integer programming code is presented.

  15. Problem-Solving Software

    NASA Technical Reports Server (NTRS)

    1992-01-01

    CBR Express software solves problems by adapting sorted solutions to new problems specified by a user. It is applicable to a wide range of situations. The technology was originally developed by Inference Corporation for Johnson Space Center's Advanced Software Development Workstation. The project focused on the reuse of software designs, and Inference used CBR as part of the ACCESS prototype software. The commercial CBR Express is used as a "help desk" for customer support, enabling reuse of existing information when necessary. It has been adopted by several companies, among them American Airlines, which uses it to solve reservation system software problems.

  16. Mouth Problems and HIV

    MedlinePlus

    ... orientation. This information is for people who have mouth (oral) problems related to HIV infection. It explains ... look like. It also describes where in the mouth they occur and how they are treated. They ...

  17. The Problem of Heroin

    ERIC Educational Resources Information Center

    Wilson, James Q.; And Others

    1972-01-01

    Argues that most of the underlying assumptions of presently recommended solutions to the problem of heroin addiction are unreasonable, unwarranted, or at least open to more than one interpretation. (DM)

  18. Enuresis: A Social Problem.

    ERIC Educational Resources Information Center

    McDonald, James E.

    1978-01-01

    Several theories and treatments of enuresis are described. The authors conclude that enuresis is a social problem (perhaps due to maturational lag, developmental delay or faulty learning) which requires teacher and parental tolerance and understanding. (SE)

  19. The cosmological constant problem

    SciTech Connect

    Dolgov, A.D.

    1989-05-01

    A review of the cosmological term problem is presented. Baby universe model and the compensating field model are discussed. The importance of more accurate data on the Hubble constant and the Universe age is stressed. 18 refs.

  20. Word Problems Made Painless.

    ERIC Educational Resources Information Center

    Noddings, Nel

    1980-01-01

    Computer assisted instruction is presented as a tool for helping students learn to successfully solve word problems. Four stages of developing a curriculum for elementary school mathematics, grades three through six, are covered. (MP)

  1. The Pesticide Problem.

    ERIC Educational Resources Information Center

    Bosch, Van Den Robert

    1979-01-01

    Contains a discussion of insects' ability to survive, of the development of pesticides and the introduction of DDT, of the problems of pesticide use and resistance to insecticides, and of the advantages of integrated pest control. (BB)

  2. Overcoming breastfeeding problems

    MedlinePlus

    Plugged milk ducts; Nipple soreness when breastfeeding; Breastfeeding - overcoming problems; Let-down reflex ... Breastfeeding (nursing) your baby can be a good experience for both the mother and the baby. It ...

  3. Down Syndrome: Eye Problems

    MedlinePlus

    ... life expectancy. Do children with Down syndrome have eye problems? Individuals with Down syndrome are at increased ... When should children with Down syndrome receive an eye exam? The American Academy of Pediatrics recommends that ...

  4. Diabetic Eye Problems

    MedlinePlus

    ... too high. Over time, this can damage your eyes. The most common problem is diabetic retinopathy. It ... light-sensitive tissue at the back of your eye. You need a healthy retina to see clearly. ...

  5. Contemporary Problems in Africa.

    ERIC Educational Resources Information Center

    O'Meara, Patrick; Winchester, N. Brian

    1987-01-01

    Provides a brief overview of political and economic developments of the past 25 years in Africa. Maintains this was a period of experimentation with vast differences in the ways in which governments dealt with human and natural problems. (JDH)

  6. The Problems of WARC.

    ERIC Educational Resources Information Center

    Pool, Ithiel de Sola

    1979-01-01

    Presents several anticipated problems to be handled at the 1979 World Administrative Conference including an orbital allocation plan, political and ideological issues concerning sovereignty and prior consent, spectrum assignments, and sharing of TV frequencies with land mobile radio. (JMF)

  7. STAGS Example Problems Manual

    NASA Technical Reports Server (NTRS)

    Knight, Norman F., Jr.; Rankin, Charles C.

    2006-01-01

    This document summarizes the STructural Analysis of General Shells (STAGS) development effort, STAGS performance for selected demonstration problems, and STAGS application problems illustrating selected advanced features available in the STAGS Version 5.0. Each problem is discussed including selected background information and reference solutions when available. The modeling and solution approach for each problem is described and illustrated. Numerical results are presented and compared with reference solutions, test data, and/or results obtained from mesh refinement studies. These solutions provide an indication of the overall capabilities of the STAGS nonlinear finite element analysis tool and provide users with representative cases, including input files, to explore these capabilities that may then be tailored to other applications.

  8. Diabetes and Foot Problems

    MedlinePlus

    ... Infographic (English) Low Blood Glucose (Hypoglycemia) Nerve Damage (Diabetic Neuropathies) Diabetic Kidney Disease Diabetes and Foot Problems Diabetic ... time, diabetes may cause nerve damage, also called diabetic neuropathy , that can cause tingling and pain, and can ...

  9. Network problem threshold

    NASA Technical Reports Server (NTRS)

    Gejji, Raghvendra, R.

    1992-01-01

    Network transmission errors such as collisions, CRC errors, misalignment, etc. are statistical in nature. Although errors can vary randomly, a high level of errors does indicate specific network problems, e.g. equipment failure. In this project, we have studied the random nature of collisions theoretically as well as by gathering statistics, and established a numerical threshold above which a network problem is indicated with high probability.

  10. Problem Solving and Reasoning

    DTIC Science & Technology

    1988-01-01

    behavior theory by investigators such as Thorndike (1923), Tolman Now at Stanford University. (1928); Skinner (1938), and Hull (1943). The h*902tion of...were developed by Gestalt psychologists Coti1ct Number N00014-79-C-0215, Contract Identification such as Khler (IM), Duncker (1935/1%5), Nuat NR 667...are necessary components goals and adopting general plans or methods in of a theory of human thought. working on a problem. Models of general problem

  11. The basketball problem

    NASA Astrophysics Data System (ADS)

    Schröer, H.

    In basketball there is the problem of hitting a basket at a determined distance and a determined height. The quantities that can be changed during the inclined throw are the initial velocity and the angle of throw. At first we neglect the air resistance. Then we treat the same problem in a medium (liquid, gas) with constant density. We obtain two differential equations. Then we view special cases of the retarding force. There is an english and a german edition.

  12. The Design of Low Order Controllers Using the Frobenius-Hankel Norm

    DTIC Science & Technology

    1990-04-01

    Engineering in the Graduate College of the University of Illinois at Urbana-Champaign, 1990 Acceso ’, For NTIS CRA&I DTIC TAB - U-1nnojnced 0...structures including lightly damped modes, decentralized structure and multiple controls and measurements. This structure has also been studied in [28] and

  13. Bicriteria network design problems

    SciTech Connect

    Marathe, M.V.; Ravi, R.; Sundaram, R.; Ravi, S.S.; Rosenkrantz, D.J.; Hunt, H.B. III

    1997-11-20

    The authors study a general class of bicriteria network design problems. A generic problem in this class is as follows: Given an undirected graph and two minimization objectives (under different cost functions), with a budget specified on the first, find a subgraph from a given subgraph class that minimizes the second objective subject to the budget on the first. They consider three different criteria -- the total edge cost, the diameter and the maximum degree of the network. Here, they present the first polynomial-time approximation algorithms for a large class of bicriteria network design problems for the above mentioned criteria. The following general types of results are presented. First, they develop a framework for bicriteria problems and their approximations. Second, when the two criteria are the same they present a black box parametric search technique. This black box takes in as input an (approximation) algorithm for the criterion situation and generates an approximation algorithm for the bicriteria case with only a constant factor loss in the performance guarantee. Third, when the two criteria are the diameter and the total edge costs they use a cluster based approach to devise approximation algorithms. The solutions violate both the criteria by a logarithmic factor. Finally, for the class of treewidth-bounded graphs, they provide pseudopolynomial-time algorithms for a number of bicriteria problems using dynamic programming. The authors show how these pseudopolynomial-time algorithms can be converted to fully polynomial-time approximation schemes using a scaling technique.

  14. Global geochemical problems

    NASA Technical Reports Server (NTRS)

    Harriss, R. C.

    1980-01-01

    Application of remote sensing techniques to the solution of geochemical problems is considered with emphasis on the 'carbon-cycle'. The problem of carbon dioxide sinks and the areal extent of coral reefs are treated. In order to assess the problems cited it is suggested that remote sensing techniques be utilized to: (1)monitor globally the carbonate and bicarbonate concentrations in surface waters of the world ocean; (2)monitor the freshwater and oceanic biomass and associated dissolved organic carbon; (3) inventory the coral reef areas and types and the associated oceanographic climatic conditions; and (4)measure the heavy metal fluxes from forested and vegetated areas, from volcanos, from different types of crustal rocks, from soils, and from sea surfaces.

  15. The Vector Decomposition Problem

    NASA Astrophysics Data System (ADS)

    Yoshida, Maki; Mitsunari, Shigeo; Fujiwara, Toru

    This paper introduces a new computational problem on a two-dimensional vector space, called the vector decomposition problem (VDP), which is mainly defined for designing cryptosystems using pairings on elliptic curves. We first show a relation between the VDP and the computational Diffie-Hellman problem (CDH). Specifically, we present a sufficient condition for the VDP on a two-dimensional vector space to be at least as hard as the CDH on a one-dimensional subspace. We also present a sufficient condition for the VDP with a fixed basis to have a trapdoor. We then give an example of vector spaces which satisfy both sufficient conditions and on which the CDH is assumed to be hard in previous work. In this sense, the intractability of the VDP is a reasonable assumption as that of the CDH.

  16. Toward Solving the Problem of Problem Solving: An Analysis Framework

    ERIC Educational Resources Information Center

    Roesler, Rebecca A.

    2016-01-01

    Teaching is replete with problem solving. Problem solving as a skill, however, is seldom addressed directly within music teacher education curricula, and research in music education has not examined problem solving systematically. A framework detailing problem-solving component skills would provide a needed foundation. I observed problem solving…

  17. Inverse heat conduction problems

    NASA Astrophysics Data System (ADS)

    Orlande, Helcio Rangel Barreto

    We present the solution of the following inverse problems: (1) Inverse Problem of Estimating Interface Conductance Between Periodically Contacting Surfaces; (2) Inverse Problem of Estimating Interface Conductance During Solidification via Conjugate Gradient Method; (3) Determination of the Reaction Function in a Reaction-Diffusion Parabolic Problem; and (4) Simultaneous Estimation of Thermal Diffusivity and Relaxation Time with Hyperbolic Heat Conduction Model. Also, we present the solution of a direct problem entitled: Transient Thermal Constriction Resistance in a Finite Heat Flux Tube. The Conjugate Gradient Method with Adjoint Equation was used in chapters 1-3. The more general function estimation approach was treated in these chapters. In chapter 1, we solve the inverse problem of estimating the timewise variation of the interface conductance between periodically contacting solids, under quasi-steady-state conditions. The present method is found to be more accurate than the B-Spline approach for situations involving small periods, which are the most difficult on which to perform the inverse analysis. In chapter 2, we estimate the timewise variation of the interface conductance between casting and mold during the solidification of aluminum. The experimental apparatus used in this study is described. In chapter 3, we present the estimation of the reaction function in a one dimensional parabolic problem. A comparison of the present function estimation approach with the parameter estimation technique, wing B-Splines to approximate the reaction function, revealed that the use of function estimation reduces the computer time requirements. In chapter 4 we present a finite difference solution for the transient constriction resistance in a cylinder of finite length with a circular contact surface. A numerical grid generation scheme was used to concentrate grid points in the regions of high temperature gradients in order to reduce discretization errors. In chapter 6, we

  18. Problem of Jerusalem.

    DTIC Science & Technology

    1985-12-16

    lllllosomo 112m 02. 11k1 __ 12U ’ S .......... MI(CROCOPY RESOLUION~ TEST CHART 1. - A 0K FILE OLMIY -- The views expressed in this paper ae those of...open publication until 00 it has been cleared by the appropriate mt0tay seice or S government agency. I * PROBLEM OF JERUSALEM BY LIEUTENANT COLONEL ALAN...COVERED Problem of Jerusalem Student Essay 6. PERFORMING ORG. REPORT NMBER 7 A THOR( s ) 8. CONTRACT OR GRANT NUMBER( s ) Alan H. Sherman 9. PERFORMING

  19. The Sedov Test Problem

    SciTech Connect

    Fung, Jimmy; Masser, Thomas; Morgan, Nathaniel R.

    2012-06-25

    The Sedov test is classically defined as a point blast problem. The Sedov problem has led us to advances in algorithms and in their understanding. Vorticity generation can be physical or numerical. Both play a role in Sedov calculations. The RAGE code (Eulerian) resolves the shock well, but produces vorticity. The source definition matters. For the FLAG code (Lagrange), CCH is superior to SGH by avoiding spurious vorticity generation. FLAG SGH currently has a number of options that improve results over traditional settings. Vorticity production, not shock capture, has driven the Sedov work. We are pursuing treatments with respect to the hydro discretization as well as to artificial viscosity.

  20. Inverse problems in mathematical physics

    NASA Astrophysics Data System (ADS)

    Glasko, V. B.

    Procedures for the correct formulation and solution of inverse problems, which usually belong to the class of ill-posed problems, are discussed. Attention is given to the concept of the conditionally correct statement of a problem, the concept of quasi-solution, and the fundamentals of regularization theory. The discussion also covers the uniqueness of solutions to inverse problems in mathematical physics, with consideration given to problems involving layered media, impedance problems, gravimetric problems, and inverse problems of heat conduction. The problem of stability and regularizing operators are also discussed.

  1. Environmental Health Problems.

    ERIC Educational Resources Information Center

    Environmental Health Service (DHEW/PHS), Rockville, MD.

    Aimed at a society which is forced to make decisions relative to their total environment, this pamphlet discusses a few of the problems associated with restoring and maintaining an environmental relationship conducive to the health and well-being of man. The topics covered include: air pollution, noise, solid waste, the urban environment, drinking…

  2. Solving Problems through Circles

    ERIC Educational Resources Information Center

    Grahamslaw, Laura; Henson, Lisa H.

    2015-01-01

    Several problem-solving interventions that utilise a "circle" approach have been applied within the field of educational psychology, for example, Circle Time, Circle of Friends, Sharing Circles, Circle of Adults and Solution Circles. This research explored two interventions, Solution Circles and Circle of Adults, and used thematic…

  3. The Problem of Consciousness.

    ERIC Educational Resources Information Center

    Crick, Francis; Koch, Christof

    1992-01-01

    Discusses approaches to the problem presented in understanding consciousness as a yet undiscovered process of interacting neuron activity. Presents the historical context of research in the area of human awareness and identifies research necessary to scientifically explain how the brain relates to the mind. (MCO)

  4. [Problem Solving Activities.

    ERIC Educational Resources Information Center

    Wisconsin Univ. - Stout, Menomonie. Center for Vocational, Technical and Adult Education.

    The teacher directed problem solving activities package contains 17 units: Future Community Design, Let's Build an Elevator, Let's Construct a Catapult, Let's Design a Recreational Game, Let's Make a Hand Fishing Reel, Let's Make a Wall Hanging, Let's Make a Yo-Yo, Marooned in the Past, Metrication, Mousetrap Vehicles, The Multi System…

  5. Expertise in Problem Solving.

    DTIC Science & Technology

    1981-05-18

    obstacles that were not encountered previously in puzzle-like problems. Basically, the exact operators to be used are usually not given, the goal state...same height on other side 5. IF something goes down frictionless surface THEN can find acceleration of gravity on the incline using trigonometry 6

  6. Solving Problems in Genetics

    ERIC Educational Resources Information Center

    Aznar, Mercedes Martinez; Orcajo, Teresa Ibanez

    2005-01-01

    A teaching unit on genetics and human inheritance using problem-solving methodology was undertaken with fourth-level Spanish Secondary Education students (15 year olds). The goal was to study certain aspects of the students' learning process (concepts, procedures and attitude) when using this methodology in the school environment. The change…

  7. Sexual Problems of Counselees.

    ERIC Educational Resources Information Center

    Heritage, Jeannette G.; West, W. Beryl

    Approximately 50% of American marriages have some sexual dysfunction. Because sexuality is an important part of a person's life, counselors should be sensitive to sexual concerns of their clients. Taking an adequate sex history and highlighting problem areas may increase counseling efficiency. When counselors teach courses on human sexuality, they…

  8. Convention Problems - 1787.

    ERIC Educational Resources Information Center

    Hanson, Deroy L.

    Designed to motivate eighth-grade civics students in the study of the United States Constitution, this game is intended to simulate the basic problems faced by the delegates to the Philadelphia Convention of 1787. The four parts of the game introduce the governmental concepts of the bicameral legislature, the executive branch, the judicial branch,…

  9. The solar neutrino problem.

    NASA Astrophysics Data System (ADS)

    Xu, Renxin; Luo, Xianhan

    1995-12-01

    The solar neutrino problem (SNP) is reviewed on the bases of neutrino physics, solar neutrino detection and standard solar model. It is interesting that the detected neutrino flux values of different solar neutrino detectors are lower than the values calculated by SMM in different degree. The studies on SNP in particle physics and in astrophysics are also discussed respectively.

  10. Circumference and Problem Solving.

    ERIC Educational Resources Information Center

    Blackburn, Katie; White, David

    The concept of pi is one of great importance to all developed civilization and one that can be explored and mastered by elementary students through an inductive and problem-solving approach. Such an approach is outlined and discussed. The approach involves the following biblical quotation: "And he made a moltin sea ten cubits from one brim to…

  11. Problems of Excess Capacity

    NASA Technical Reports Server (NTRS)

    Douglas, G.

    1972-01-01

    The problems of excess capacity in the airline industry are discussed with focus on the following topics: load factors; fair rate of return on investment; service-quality rivalry among airlines; pricing (fare) policies; aircraft production; and the impacts of excess capacity on operating costs. Also included is a discussion of the interrelationships among these topics.

  12. and Internalizing Behavior Problems

    ERIC Educational Resources Information Center

    Hofer, Claire; Eisenberg, Nancy; Spinrad, Tracy L.; Morris, Amanda S.; Gershoff, Elizabeth; Valiente, Carlos; Kupfer, Anne; Eggum, Natalie D.

    2013-01-01

    Stability and change in mother-adolescent conflict reactions (CRs) and the prediction of CRs from adolescents' earlier behavior problems (and vice versa) were examined with 131 mothers and their adolescents (63 boys). Dyads engaged in a 6-min conflict discussion twice, 2 years apart ["M" age was 13 at Time 1 (T1)]. Non-verbal expressive…

  13. The Problems of Translation.

    ERIC Educational Resources Information Center

    Huntsman, Jeffrey F.

    The problems confronting the translator of American Indian literature are immense. The history of European Indian relations has obscured many original Indian values and attitudes and has substituted a set of simplistic and unreal Anglo attitudes that translators must transcend. Unlike most Western literature, Indian literature does not instruct,…

  14. Solving Common Mathematical Problems

    NASA Technical Reports Server (NTRS)

    Luz, Paul L.

    2005-01-01

    Mathematical Solutions Toolset is a collection of five software programs that rapidly solve some common mathematical problems. The programs consist of a set of Microsoft Excel worksheets. The programs provide for entry of input data and display of output data in a user-friendly, menu-driven format, and for automatic execution once the input data has been entered.

  15. Solving Problems Reductively

    ERIC Educational Resources Information Center

    Armoni, Michal; Gal-Ezer, Judith; Tirosh, Dina

    2005-01-01

    Solving problems by reduction is an important issue in mathematics and science education in general (both in high school and in college or university) and particularly in computer science education. Developing reductive thinking patterns is an important goal in any scientific discipline, yet reduction is not an easy subject to cope with. Still,…

  16. Children Solve Problems.

    ERIC Educational Resources Information Center

    De Bono, Edward

    A group of children were presented with several tasks, including the invention of a sleep machine and a machine to weigh elephants. The tasks were chosen to involve the children in coping with problems of a distinct character. A study of the children's drawings and interpretations shows that children's thinking ability is not very different from…

  17. Dynamical impurity problems

    SciTech Connect

    Emery, V.J.; Kivelson, S.A.

    1993-12-31

    In the past few years there has been a resurgence of interest in dynamical impurity problems, as a result of developments in the theory of correlated electron systems. The general dynamical impurity problem is a set of conduction electrons interacting with an impurity which has internal degrees of freedom. The simplest and earliest example, the Kondo problem, has attracted interest since the mid-sixties not only because of its physical importance but also as an example of a model displaying logarithmic divergences order by order in perturbation theory. It provided one of the earliest applications of the renormalization group method, which is designed to deal with just such a situation. As we shall see, the antiferromagnetic Kondo model is controlled by a strong-coupling fixed point, and the essence of the renormalization group solution is to carry out the global renormalization numerically starting from the original (weak-coupling) Hamiltonian. In these lectures, we shall describe an alternative route in which we identify an exactly solvable model which renormalizes to the same fixed point as the original dynamical impurity problem. This approach is akin to determining the critical behavior at a second order phase transition point by solving any model in a given universality class.

  18. Problem Patron Manual.

    ERIC Educational Resources Information Center

    Brown, Marion, Comp.; And Others

    This document presents guidelines for handling disruptive behavior in the Schenectady County Public Library (New York). Specific responses are listed for dealing with questions about library selection policy and sudden patron illness or injury. Also listed are responses to problem situations involving angry or irate patrons, assault or physically…

  19. The real problem.

    PubMed

    Godfrey, M

    1997-01-01

    I really was dismayed to see the basic cause of all our planet's problems buried in the September/October 96 issue: "...religious zealots might wreck the family planning needs of a billion people...." Let's face hard facts: all these problems would go away if the planet's population were small enough. What we really need to establish is what the population of the earth should be, and then set out to achieve that population as soon as possible. All of our efforts to reduce automobile pollution, the amount of reactor waste, the number of species being obliterated, etc., are just postponing the inevitable. What we need to look at, and keep track of, are those factors that encourage expanding population and discourage population control. For example, most businesses like to see the population expand so they can have a growing customer base. I truly appreciate your efforts. But if we are going to get anywhere we have to clearly identify the real problem. And then we have to break it down into manageable pieces and go to work on them. Otherwise we are going to keep looking at the graphs and wringing our hands as this accumulation of problems builds until it sweeps over us like a giant tsunami.

  20. Human Population Problems

    ERIC Educational Resources Information Center

    Emmel, Thomas C.; Sligh, Michael M.

    1970-01-01

    Asserts that overpopulation is the most pressing world problem. Topics discussed include population control in primitive societies, population growth and control in modern societies, methods of motivational population control, consequences of no population control, and mass famines during the 1970's in underdeveloped countries. Cities 33…

  1. Tackling a Local Problem.

    ERIC Educational Resources Information Center

    Cook, Martin

    1995-01-01

    Students studying water as a class project were concerned by levels of pollution at a nearby river and the local beach. They identified three environmental problems for research including sewage discharge, beach litter, and quality of swimming water. Research consisted of field trips which allowed for opportunities to improve skills in collecting…

  2. Managing Global Problems.

    ERIC Educational Resources Information Center

    Stanley, C. Maxwell

    The book examines the historical background of and accomplishments in seven global problem areas. It is hypothesized that effective management within today's framework is the only way to progress toward the political and economic order that is necessary to assure peace and security, justice, and human rights, and to improve the quality of life. It…

  3. A Multifaceted Minimization Problem.

    ERIC Educational Resources Information Center

    Pomeranz, Janet Bellcourt

    1983-01-01

    The problem "Given three planar points, find a point such that the sum of the distances from that point to the three points is a minimum" is discussed from several points of view. A solution that uses only calculus and geometry is examined in detail. (MNS)

  4. Constructed-Response Problems

    ERIC Educational Resources Information Center

    Swinford, Ashleigh

    2016-01-01

    With rigor outlined in state and Common Core standards and the addition of constructed-response test items to most state tests, math constructed-response questions have become increasingly popular in today's classroom. Although constructed-response problems can present a challenge for students, they do offer a glimpse of students' learning through…

  5. Unfolding a Problem

    ERIC Educational Resources Information Center

    Currier, Sarah Cox

    2015-01-01

    In this article, Sarah Currier, a math specialist at Elizabeth Hall International School in Minnesota, describes how she used origami in a deliberate manner to teach content. She shares how she uses paper folding to teach mathematical concepts, reinforce vocabulary, and as a problem-solving model. She also offers ideas for using origami in other…

  6. Achievement in Problem Solving

    ERIC Educational Resources Information Center

    Friebele, David

    2010-01-01

    This Action Research Project is meant to investigate the effects of incorporating research-based instructional strategies into instruction and their subsequent effect on student achievement in the area of problem-solving. The two specific strategies utilized are the integration of manipulatives and increased social interaction on a regular basis.…

  7. Introspection in Problem Solving

    ERIC Educational Resources Information Center

    Jäkel, Frank; Schreiber, Cornell

    2013-01-01

    Problem solving research has encountered an impasse. Since the seminal work of Newell und Simon (1972) researchers do not seem to have made much theoretical progress (Batchelder and Alexander, 2012; Ohlsson, 2012). In this paper we argue that one factor that is holding back the field is the widespread rejection of introspection among cognitive…

  8. The Eight Queens Problem.

    ERIC Educational Resources Information Center

    Olson, Alton T.

    1993-01-01

    Presents a series of solution methods to the Eight Queens Problem of placing eight queens on a chess board so that no one queen can capture another. Solution methods progress from empirical approaches to the use of computer algorithms. Geometric transformations are used to find other solutions. (MDH)

  9. Problem Classification in Counseling.

    ERIC Educational Resources Information Center

    Klimes, Rudolf E.

    1992-01-01

    This paper describes a framework for counselors that will help them classify personal and social problems of clients for base-line and end-line comparisons. Counseling's goal, as presented here, is to help individuals for a lifetime; therapy is not seen as the giving of advice or solutions, but as a teaching process through which clients become…

  10. Universal Design Problem Solving

    ERIC Educational Resources Information Center

    Sterling, Mary C.

    2004-01-01

    Universal design is made up of four elements: accessibility, adaptability, aesthetics, and affordability. This article addresses the concept of universal design problem solving through experiential learning for an interior design studio course in postsecondary education. Students' experiences with clients over age 55 promoted an understanding of…

  11. Managing soil remediation problems.

    PubMed

    Okx, J P; Hordijk, L; Stein, A

    1996-12-01

    Soil remediation has only a short history but the problem addressed is a significant one. Cost estimates for the clean-up of contaminated sites in the European Union and the United States are in the order of magnitude of 1,400 billion ECU. Such an enormous operation deserves the best management it can get. Reliable cost estimations per contaminated site are an important prerequisite. This paper addresses the problems related to site-wise estimations.When solving soil remediation problems, we have to deal with a large number of scientific disciplines. Too often solutions are presented from the viewpoint of only one discipline. In order to benefit from the combined disciplinary knowledge and experience, we think that it is necessary to describe the interrelations between these disciplines. This can be realized by developing an adequate model of the desired process which enables to consider and evaluate the essential factors as interdependent components of the total system.The resulting model provides a binding paradigm to the contributing disciplines which will result in improved efficiency and effectivity of the decision and the cost estimation process. In the near future, we will release the "Biosparging and Bioventing Expert Support System", an expert support system for problem owners, consultants and authorities dealing with the design and operation of a biosparging and/or a bioventing system.

  12. Chemical Reaction Problem Solving.

    ERIC Educational Resources Information Center

    Veal, William

    1999-01-01

    Discusses the role of chemical-equation problem solving in helping students predict reaction products. Methods for helping students learn this process must be taught to students and future teachers by using pedagogical skills within the content of chemistry. Emphasizes that solving chemical reactions should involve creative cognition where…

  13. A model for routing problem in quay management problem

    NASA Astrophysics Data System (ADS)

    Zirour, Mourad; Oughalime, Ahmed; Liong, Choong-Yeun; Ismail, Wan Rosmanira; Omar, Khairuddin

    2014-06-01

    Quadratic Assignment Problem (QAP), like Vehicle Routing Problem, is one of those optimization problems that interests many researchers in the last decades. The Quay Management Problem is a specific problem which could be presented as a QAP which involves a double assignment of customers and products toward loading positions using lifting trucks. This study focuses on the routing problem while delivering the customers' demands. In this problem, lifting trucks will route around the storage sections to collect the products then deliver to the customers who are assigned to specific loading positions. The objective of minimizing the residence time for each customer is sought. This paper presents the problem and the proposed model.

  14. Buffon's Coin Problem and beyond

    ERIC Educational Resources Information Center

    Schneiter, Kady

    2011-01-01

    This article describes an investigation of Buffon's coin problem and related problems with the aid of an applet. The problems are accessible at a variety of grade levels and facilitate making connections between geometry and probability.

  15. Gravitational Many-Body Problem

    SciTech Connect

    Makino, J.

    2008-04-29

    In this paper, we briefly review some aspects of the gravitational many-body problem, which is one of the oldest problems in the modern mathematical science. Then we review our GRAPE project to design computers specialized to this problem.

  16. Gravitational Many-Body Problem

    NASA Astrophysics Data System (ADS)

    Makino, J.

    2008-04-01

    In this paper, we briefly review some aspects of the gravitational many-body problem, which is one of the oldest problems in the modern mathematical science. Then we review our GRAPE project to design computers specialized to this problem.

  17. Solving A Corrosion Problem

    NASA Technical Reports Server (NTRS)

    1979-01-01

    The corrosion problem, it turned out, stemmed from the process called electrolysis. When two different metals are in contact, an electrical potential is set up between them; when the metals are surrounded by an electrolyte, or a conducting medium, the resulting reaction causes corrosion, often very rapid corrosion. In this case the different metals were the copper grounding system and the ferry's aluminum hull; the dockside salt water in which the hull was resting served as the electrolyte. After identifying the source of the trouble, the Ames engineer provided a solution: a new wire-and-rod grounding system made of aluminum like the ferry's hull so there would no longer be dissimilar metals in contact. Ames research on the matter disclosed that the problem was not unique to the Golden Gate ferries. It is being experienced by many pleasure boat operators who are probably as puzzled about it as was the Golden Gate Transit Authority.

  18. FBST for Cointegration Problems

    NASA Astrophysics Data System (ADS)

    Diniz, M.; Pereira, C. A. B.; Stern, J. M.

    2008-11-01

    In order to estimate causal relations, the time series econometrics has to be aware of spurious correlation, a problem first mentioned by Yule [21]. To solve the problem, one can work with differenced series or use multivariate models like VAR or VEC models. In this case, the analysed series are going to present a long run relation i.e. a cointegration relation. Even though the Bayesian literature about inference on VAR/VEC models is quite advanced, Bauwens et al. [2] highlight that "the topic of selecting the cointegrating rank has not yet given very useful and convincing results." This paper presents the Full Bayesian Significance Test applied to cointegration rank selection tests in multivariate (VAR/VEC) time series models and shows how to implement it using available in the literature and simulated data sets. A standard non-informative prior is assumed.

  19. Medical problems in pregnancy.

    PubMed

    Narayan, Bhaskar; Nelson-Piercy, Catherine

    2016-12-01

    The prevalence of medical problems in pregnancy is increasing because of a complex interplay between demographic and lifestyle factors, and developments in modern medicine. Maternal mortality and morbidity resulting from treatable medical conditions, such as venous thromboembolism, epilepsy and autoimmune disease, have not decreased in recent years. This is despite a marked decrease in overall maternal mortality. It is vital that all physicians acquire a basic knowledge and understanding of medical problems in pregnancy. This includes prepregnancy measures such as counselling and optimisation of medical therapy, as well as multidisciplinary management throughout pregnancy and the postpartum period. Prompt recognition and treatment of acute and chronic illness is of clear benefit, and most drugs and many radiological investigations may be used in pregnancy.

  20. Modern problems of thermodynamics

    NASA Astrophysics Data System (ADS)

    Novikov, I. I.

    2012-12-01

    The role of energy and methods of its saving for the development of human society and life are analyzed. The importance of future use of space energy flows and energy of water and air oceans is emphasized. The authors consider the idea of the unit for production of electric energy and pure substances using sodium chloride which reserves are limitless on the planet. Looking retrospectively at the development of power engineering from the elementary fire to modern electric power station, we see that the used method of heat production, namely by direct interaction of fuel and oxidizer, is the simplest. However, it may be possible to combust coal, i.e., carbon in salt melt, for instance, sodium chloride that would be more rational and efficient. If the stated problems are solved positively, we would master all energy properties of the substance; and this is the main problem of thermodynamics being one of the sciences on energy.

  1. Solving bearing overheating problems

    SciTech Connect

    Jendzurski, T.

    1995-05-08

    Overheating is a major indicator, along with vibration and noise, of an underlying problem affecting a bearing or related components. Because normal operating temperatures vary widely from one application to another, no single temperature is a reliable sign of overheating in every situation. By observing an application when it is running smoothly, a technician can establish a benchmark temperature for a particular bearing arrangement. Wide deviations from this accepted norm generally indicate troublesome overheating. The list of possible causes of over-heating ranges from out-of-round housings and oversize shaft diameters to excessive lubrication and bearing preloading. These causes fall into two major categories: improper or faulty lubrication and mechanical problems, such as incorrect fits and tolerances. These are discussed along with solutions.

  2. The inhibiting bisection problem.

    SciTech Connect

    Pinar, Ali

    2010-11-01

    Given a graph where each vertex is assigned a generation or consumption volume, we try to bisect the graph so that each part has a significant generation/consumption mismatch, and the cutsize of the bisection is small. Our motivation comes from the vulnerability analysis of distribution systems such as the electric power system. We show that the constrained version of the problem, where we place either the cutsize or the mismatch significance as a constraint and optimize the other, is NP-complete, and provide an integer programming formulation. We also propose an alternative relaxed formulation, which can trade-off between the two objectives and show that the alternative formulation of the problem can be solved in polynomial time by a maximum flow solver. Our experiments with benchmark electric power systems validate the effectiveness of our methods.

  3. Working on interesting problems

    NASA Astrophysics Data System (ADS)

    Smith, Arfon M.

    2015-01-01

    BSc Chemistry, The University of Sheffield 2001... PhD Astrochemistry, The University of Nottingham 2006... Scientist at GitHub Inc. 2013.From the outside, the path an individual has taken from academia to industry is not an obvious one. In this session I'll (try and) explain how an interest in software, engineering and chasing interesting problems makes internet startup in San Francisco a great home.

  4. Collinear Points Problem

    ERIC Educational Resources Information Center

    Shultz, Harris S.; Shiflett, Ray C.

    2008-01-01

    Students were asked to find all possible values for A so that the points (1, 2), (5, A), and (A, 7) lie on a straight line. This problem suggests a generalization: Given (x, y), find all values of A so that the points (x, y), (5, A), and (A, 7) lie on a straight line. We find that this question about linear equations must be resolved using the…

  5. Problems with corneal arcus.

    PubMed

    Fielder, A R; Winder, A F; Sheraidah, G A; Cooke, E D

    1981-01-01

    Corneal arcus presents many puzzling features. The correlation between its incidence and serum lipid levels is poor and, using immunoelectrophoresis, we have only been able to identify low-density lipoprotein inconsistently in corneae containing this deposition. Infrared thermography has shown us that arcus commences in the warmest regions of the cornea. We have considered the possible relevance of our biochemical and thermographic findings to other problems with corneal arcus such as its irreversibility, anatomical distribution, and clear zone.

  6. The Henry Problem Revisited

    NASA Astrophysics Data System (ADS)

    Karasaki, K.; Oldenburg, C. M.; Maekawa, K.

    2006-12-01

    We have modeled laboratory experiments of saltwater intrusion in a configuration resembling the so-called Henry Problem using TOUGH2/EOS7. The experiment differs from the Henry Problem in that the freshwater boundary condition is that of Dirichlet, a difference that is not expected to affect the overall results very much. The simulation matched the saltwater wedge profile of the experiment, the main feature of which was the sharp interface (lack of dispersion) between the freshwater and saltwater. Prior solutions of the Henry Problem show a wide transition zone between freshwater and saltwater arising from the use of a large dispersion coefficient. Henry attributed the large dispersion to the effect of tidally induced motion. In our simulation, we imposed a time-varying sinusoidal boundary condition to see if a larger transition zone can be created without using a larger dispersion coefficient. However, for the parameters used we were not able to do so. It is still plausible that the wide transition zone observed at Biscayne Bay (and as modeled in the Henry Problem) is caused by a particular formation heterogeneity and transient effects. Our analysis, based on a laboratory experiment and accompanying modeling, suggests that dispersion is quite limited. Nonetheless, we question the validity of the use of a large dispersion coefficient where the groundwater velocity is very low, or where the flow is in the opposite direction of the concentration gradient. This work was supported by the U.S. Department of Energy under Contract No. DE-AC02-05CH11231

  7. Dynamic bin packing problem

    NASA Technical Reports Server (NTRS)

    Dikshit, Piyush; Guimaraes, Katia; Ramamurthy, Maya; Agrawala, Ashok K.; Larsen, Ronald L.

    1989-01-01

    In a previous work we have defined a general architecture model for autonomous systems, which can be mapped easily to describe the functions of any automated system (SDAG-86-01). In this note, we use the model to describe the problem of thermal management in space stations. First we briefly review the architecture, then we present the environment of our application, and finally we detail the specific function for each functional block of the architecture for that environment.

  8. Problem Solving and Reasoning.

    DTIC Science & Technology

    1984-02-01

    Sloan Foundation (HAS). This paper is a draft of a chapter to appear in R. C. Atkinson, R. Herrnstein, G. Lindzey, and R. D. Luce (Eds.), Stevens ...D. Luce (Eds.), Stevens ’ Handbook of Experimental Psychology, (Revised Edition). New York: John Wiley & Sons. PROBLEM SOLVING AND REASONING James G... LaBerge & S. J. Samuels (Eds.), Perception and comprehension. Hillsdale, NJ: Erlbaum. Anderson, J. R. (1982). Acquisition of cognitive skill

  9. Impact and Penetration Problems.

    DTIC Science & Technology

    1981-03-16

    is the atomic distance and 2Z is the punch width. The nonlocal analysis of the rigid punch problem leads to the following conclusions: i) flonlocal...classical analysis , the viscous stresses at the periphery of the plug are found to be finite. (ii) The critical velocity for the initial plug formation is...effects. In addition, the nonlocal inter- molecular forces must be taken into account. In [10], a nonlocal analysis of plug formation in visco-plastic

  10. Buffon's needle problem

    NASA Astrophysics Data System (ADS)

    Schröer, H.

    We accidentally let a needle fall with the length L on a table. On the table are drawn parallel lines with distance D. We assume L is smaller than D. We introduce the rotation probability. Then we generalize the Buffon's needle problem. We view a general convex set. We have to solve a two-dimensional integral. There is an english and a german edition.

  11. Energy - A systems problem

    NASA Technical Reports Server (NTRS)

    Bourke, Roger D.

    1982-01-01

    Energy management in its most comprehensive sense encompasses economic, technical, environmental, and political problems. The present evaluation of prospects notes that opportunities for energy conservation are widespread, in such fields as building air conditioning, transportation, electrical appliances, and industrial processes. Further conservation is expected to be achieved through a combination of technology development and economics; the latter factor must not be unduly influenced by political measures that shield consumers from the true cost of energy.

  12. High Altitude Medical Problems

    PubMed Central

    Hultgren, Herbert N.

    1979-01-01

    Increased travel to high altitude areas by mountaineers and nonclimbing tourists has emphasized the clinical problems associated with rapid ascent. Acute mountain sickness affects most sojourners at elevations above 10,000 feet. Symptoms are usually worse on the second or third day after arrival. Gradual ascent, spending one to three days at an intermediate altitude, and the use of acetazolamide (Diamox) will prevent or ameliorate symptoms in most instances. Serious and potentially fatal problems, such as high altitude pulmonary edema or cerebral edema, occur in approximately 0.5 percent to 1.0 percent of visitors to elevations above 10,000 feet—especially with heavy physical exertion on arrival, such as climbing or skiing. Early recognition, high flow oxygen therapy and prompt descent are crucially important in management. Our knowledge of the causes of these and other high altitude problems, such as retinal hemorrhage, systemic edema and pulmonary hypertension, is still incomplete. Even less is known of the effect of high altitudes on medical conditions common at sea level or on the action of commonly used drugs. ImagesFigure 2. PMID:483805

  13. Ear problems in swimmers.

    PubMed

    Wang, Mao-Che; Liu, Chia-Yu; Shiao, An-Suey; Wang, Tyrone

    2005-08-01

    Acute diffuse otitis externa (swimmer's ear), otomycosis, exostoses, traumatic eardrum perforation, middle ear infection, and barotraumas of the inner ear are common problems in swimmers and people engaged in aqua activities. The most common ear problem in swimmers is acute diffuse otitis externa, with Pseudomonas aeruginosa being the most common pathogen. The symptoms are itching, otalgia, otorrhea, and conductive hearing loss. The treatment includes frequent cleansing of the ear canal, pain control, oral or topical medications, acidification of the ear canal, and control of predisposing factors. Swimming in polluted waters and ear-canal cleaning with cotton-tip applicators should be avoided. Exostoses are usually seen in people who swim in cold water and present with symptoms of accumulated debris, otorrhea and conductive hearing loss. The treatment for exostoses is transmeatal surgical removal of the tumors. Traumatic eardrum perforations may occur during water skiing or scuba diving and present with symptoms of hearing loss, otalgia, otorrhea, tinnitus and vertigo. Tympanoplasty might be needed if the perforations do not heal spontaneously. Patients with chronic otitis media with active drainage should avoid swimming, while patients who have undergone mastoidectomy and who have no cavity problems may swim. For children with ventilation tubes, surface swimming is safe in a clean, chlorinated swimming pool. Sudden sensorineural hearing loss and some degree of vertigo may occur after diving because of rupture of the round or oval window membrane.

  14. The Feline Josephus Problem

    NASA Astrophysics Data System (ADS)

    Ruskey, Frank; Williams, Aaron

    In the classic Josephus problem, elements 1, 2,...,n are placed in order around a circle and a skip value k is chosen. The problem proceeds in n rounds, where each round consists of traveling around the circle from the current position, and selecting the kth remaining element to be eliminated from the circle. After n rounds, every element is eliminated. Special attention is given to the last surviving element, denote it by j. We generalize this popular problem by introducing a uniform number of lives ℓ, so that elements are not eliminated until they have been selected for the ℓth time. We prove two main results: 1) When n and k are fixed, then j is constant for all values of ℓ larger than the nth Fibonacci number. In other words, the last surviving element stabilizes with respect to increasing the number of lives. 2) When n and j are fixed, then there exists a value of k that allows j to be the last survivor simultaneously for all values of ℓ. In other words, certain skip values ensure that a given position is the last survivor, regardless of the number of lives. For the first result we give an algorithm for determining j (and the entire sequence of selections) that uses O(n 2) arithmetic operations.

  15. On the Feynman Problem

    NASA Astrophysics Data System (ADS)

    D'Ariano, Giacomo

    2012-02-01

    Foundations of Quantum Field Theory can be connected to foundations of Quantum Theory if we can derive the former in terms of the latter with two additional postulates of locality and topological homogeneity of interactions between quantum systems, in the hypothesis that a quantum field is ultimately made of a numerable set of quantum systems that are unitarily interacting. But, in order to do that we need to be able to simulate quantumm field by a quantum computer. In the paper ``Simulating Physics with Computers'' (Int. J. Th. Phys, 21 467 (1982)) Richard Feynman raised the problem whether it is possible to simulate Fermi fields by a quantum computer---in short if we can ``qubit-ize'' a Fermi field, keeping the field interaction local on qubits. In this talk I will show how this problem is solved for any space-dimension, upon introducing a new general Jordan-Wigner map between field and qubits, and by adding witnessing auxiliary qubits. I will also derive the unique vacuum for the Fermi fields and for the auxiliary fields. The solution of the Feynman problem allows us to simulate quantum fields by a quantum cellular automata, also providing a kind of Planck-scale version of quantum field theory. Computer simulations will be projected at the end of the talk

  16. Measuring Family Problem Solving: The Family Problem Solving Diary.

    ERIC Educational Resources Information Center

    Kieren, Dianne K.

    The development and use of the family problem-solving diary are described. The diary is one of several indicators and measures of family problem-solving behavior. It provides a record of each person's perception of day-to-day family problems (what the problem concerns, what happened, who got involved, what those involved did, how the problem…

  17. Thinking Process of Naive Problem Solvers to Solve Mathematical Problems

    ERIC Educational Resources Information Center

    Mairing, Jackson Pasini

    2017-01-01

    Solving problems is not only a goal of mathematical learning. Students acquire ways of thinking, habits of persistence and curiosity, and confidence in unfamiliar situations by learning to solve problems. In fact, there were students who had difficulty in solving problems. The students were naive problem solvers. This research aimed to describe…

  18. Problem-Framing: A perspective on environmental problem-solving

    NASA Astrophysics Data System (ADS)

    Bardwell, Lisa V.

    1991-09-01

    The specter of environmental calamity calls for the best efforts of an involved public. Ironically, the way people understand the issues all too often serves to discourage and frustrate rather than motivate them to action. This article draws from problem-solving perspectives offered by cognitive psychology and conflict management to examine a framework for thinking about environmental problems that promises to help rather than hinder efforts to address them. Problem-framing emphasizes focusing on the problem definition. Since how one defines a problem determines one's understanding of and approach to that problem, being able to redefine or reframe a problem and to explore the “problem space” can help broaden the range of alternatives and solutions examined. Problem-framing incorporates a cognitive perspective on how people respond to information. It explains why an emphasis on problem definition is not part of people's typical approach to problems. It recognizes the importance of structure and of having ways to organize that information on one's problem-solving effort. Finally, problem-framing draws on both cognitive psychology and conflict management for strategies to manage information and to create a problem-solving environment that not only encourages participation but can yield better approaches to our environmental problems.

  19. Space Power Engineering Problems

    NASA Astrophysics Data System (ADS)

    Senkevich, V. P.

    2002-01-01

    Development of space power engineering in the first half of XXI century shall be aimed at preventing the forthcoming energy crisis and ecological catastrophes. The problem can be solved through using solar energy being perpetual, endless, and ecologically safe. As of now, issues on the development and employment of solar power stations and its beaming to the ground stations in the SHF band are put on the agenda. The most pressing problem is to develop orbital solar reflectors to illuminate towns in the polar regions, agricultural regions, and areas of processing sea products. Space-based technologies can be used to deal with typhoons, green house effects, and "ozone holes". Recently, large, frameless film structures formed by centrifugal forces offer the promise of structures for orbital power plants, reflectors, and solar sails. A big success is achieved in the development of power generating solar array elements of amorphous silicon. These innovations would make the development of orbital solar power plants dozens of times cheaper. Such solar arrays shall be used in the nearest future on heavy communication satellites and the Earth remote sensing platforms for generation of 140-160 kW at a specific power beyond 300 W/kg. The cargo traffic needed to develop and maintain the orbital power plants and reflector systems could be equipped with solar sails as the future low thrust propulsion. In 2000, the mankind witnessed an unexpected beginning of energy crisis along with strong hydro- meteorological events (typhoons, floods) that shocked the USA, the Western Europe, England, Japan, and other countries. The total damage is estimated as 90 billions of dollars. The mankind is approaching a boundary beyond which its further existence would depend on how people would learn to control weather and use ecologically safe power sources. Space technology base on the research potential accumulated in the previous century could serve for the solution of this problem.

  20. The symbol detachment problem.

    PubMed

    Pezzulo, Giovanni; Castelfranchi, Cristiano

    2007-06-01

    In situated and embodied approaches it is commonly assumed that the dynamics of sensorimotor engagement between an adaptive agent and its environment are crucial in understanding natural cognition. This perspective permits to address the symbol grounding problem, since the aboutness of any mental state arising during agent-environment engagement is guaranteed by their continuous coupling. However, cognitive agents are also able to formulate representations that are detached from the current state of affairs, such as expectations and goals. Moreover, they can act on their representations before--or instead of--acting directly on the environment, for example building the plan of a bridge and not directly the bridge. On the basis of representations, actions such as planning, remembering or imagining are possible that are disengaged from the current sensorimotor cycle, and often functional to future-oriented conducts. A new problem thus has to be acknowledged, the symbol detachment problem: how and why do situated agents develop representations that are detached from their current sensorimotor interaction, but nevertheless preserve grounding and aboutness? How do cognitive agents progressively acquire a range of capabilities permitting them to deal not only with the current situation but also with alternative, in particular future states of affairs? How do they develop the capability of acting on their representations instead of acting directly on the world? In a theoretical and developmental perspective, we propose that anticipation plays a crucial role in the detachment process: anticipatory representations, originally detached from the sensorimotor cycle for the sake of action control, are successively exapted for bootstrapping increasingly complex cognitive capabilities.

  1. Model for assessing psychosocial problems.

    PubMed Central

    Tannenbaum, D.; McGillivray, M.

    1996-01-01

    The Model for the Assessment of Psychosocial Problems (MAPP) can help family medicine residents effectively assess patients with psychosocial problems. Following a patient-centred clinical method, MAPP provides a guide to exploring problems and an approach that allows residents and patients jointly to define problems and decide upon management. Emphasis is placed on clarifying patients' expectations of physicians. PMID:9222578

  2. Problem Order Implications for Learning

    ERIC Educational Resources Information Center

    Li, Nan; Cohen, William W.; Koedinger, Kenneth R.

    2013-01-01

    The order of problems presented to students is an important variable that affects learning effectiveness. Previous studies have shown that solving problems in a blocked order, in which all problems of one type are completed before the student is switched to the next problem type, results in less effective performance than does solving the problems…

  3. Problem-Based Learning Tools

    ERIC Educational Resources Information Center

    Chin, Christine; Chia, Li-Gek

    2008-01-01

    One way of implementing project-based science (PBS) is to use problem-based learning (PBL), in which students formulate their own problems. These problems are often ill-structured, mirroring complex real-life problems where data are often messy and inclusive. In this article, the authors describe how they used PBL in a ninth-grade biology class in…

  4. Problem Solving: Tips for Teachers.

    ERIC Educational Resources Information Center

    O'Daffer, Phares G., Ed.; Schaaf, Oscar

    1986-01-01

    Describes: (1) a computation-oriented problem with procedures and some questions that might be asked of students; (2) four ways to help students develop positive problem-solving attitudes; (3) a strategy game; (4) a multiplication problem; and (5) several questions that will help students develop problem-solving skills. (JN)

  5. Creating Games from Mathematical Problems

    ERIC Educational Resources Information Center

    Pinter, Klara

    2011-01-01

    The emphasis on problem solving and problem solving courses has become a standard staple of most teacher preparation programs in mathematics. While opinions differ on whether problem solving should be integrated throughout the preparatory courses or teachers should also have a dedicated course for it, everybody agrees that problem solving skills…

  6. Environmental problems of runners.

    PubMed

    Stanitski, C L

    1985-10-01

    By its very nature, running allows for a freedom that many athletic endeavors lack. The ability to run anytime and anywhere may be detrimental in itself, in that it may allow runners to place themselves in environmental circumstances that are unhealthy. Acclimatization to heat, altitude, and air pollution conditions can occur. Rapid changes in environment brought about by travel may lead to lack of recognition of appropriate clothing or running routes. Usual workout intensities and durations may not be appropriate for the specific environment at hand. Runners are advised to recognize the potential for such problems and make adjustments accordingly.

  7. Problems of neural memory

    NASA Astrophysics Data System (ADS)

    Mikaelian, Andrei L.

    2005-01-01

    The paper considers the neural memory of the human brain from the viewpoint of visual information processing. A model that explains the principle of data recording and storing, memory relaxation, associative remembering and other memory functions is offered. The model of associative memory is based on the methods of holography, "wave biochemistry" and autowaves. Brief consideration is given to the associative properties of holographic neural structures and the memory architecture using running chemical reactions. The paper also outlines the problem of developing artificial memory elements for restoring the brain functions and possible interface devices for coupling neurons to electronic systems.

  8. Irrelevance in Problem Solving

    NASA Technical Reports Server (NTRS)

    Levy, Alon Y.

    1992-01-01

    The notion of irrelevance underlies many different works in AI, such as detecting redundant facts, creating abstraction hierarchies and reformulation and modeling physical devices. However, in order to design problem solvers that exploit the notion of irrelevance, either by automatically detecting irrelevance or by being given knowledge about irrelevance, a formal treatment of the notion is required. In this paper we present a general framework for analyzing irrelevance. We discuss several properties of irrelevance and show how they vary in a space of definitions outlined by the framework. We show how irrelevance claims can be used to justify the creation of abstractions thereby suggesting a new view on the work on abstraction.

  9. Planning and Problem Solving

    DTIC Science & Technology

    1982-10-01

    Artificial Intelig ~ence (Vol. III, edited by Paul R. Cohen and’ Edward A.. Feigenbaum)’, The chapter was written B’ Paul Cohen, with contributions... Artificial Intelligence (Vol. III, edited by Paul R. Cohen and EdWard A. Feigenbaum). The chapter was written by Paul R. Cohen, with contributions by Stephen...Wheevoats"EntermdI’ Planning and Problem ’Solving by Paul R. Cohen Chaptb-rXV-of Volumec III’of the Handbook of Artificial Intelligence edited by Paul R

  10. The population problem?

    PubMed

    Mcelroy, W

    1968-01-01

    Most governments that have considered the population problem have been doing a part time job, working to stabilize the population by spreading knowledge of oral contraception (OC) and other contraceptive devices. An inadequate job is being done in promoting the reduction of the birthrate. What is needed is an all out effort from all countries concerned. It was only in 1965 that a President of the US for the 1st time made a positive statement about the government's position and support for family planning programs. Until then all government agencies were careful to avoid discussing this matter in opening meetings. Thereafter, President Johnson repeatedly indicated that he recognized the seriousness of the problem and the need for intelligent and direct action. Yet, the appropriation and distribution of funds for population control in the US and developing countries has failed to keep pace with the superlative statements made by national and responsible individuals on the importance of the problem. Family planning is more than a program just for the distribution of contraceptive devices. Where knowledgeable personnel are available, they try to identify the broad social problems resulting from large familles. They try to influence the behavior of the individual couples with regard to family size. Yet, even in the US the number of personnel is inadequate to carry out this large educational program. The Committee on Population of the National Academy of Sciences stressed several points: a zero rate of population growth may prove essential in the long run but as a goal within the time horizon of present policy it has little support in either the developed or developing countries, certainly not among governments; a need exists for exploration of a broader range of measures for their potential contribution to the easing of population pressures, particularly in the developing countries where rapid population growth is particularly threatening; programs of social change need

  11. Touching the problem.

    PubMed

    Pendergast, M

    1999-01-01

    This article discusses the stand of the Catholic Church concerning HIV prevention through the use of condoms or any other forms of artificial contraception. It is a known fact that the problem of HIV/AIDS needs worldwide attention, and yet the Vatican rails against HIV prevention programs which appear to promote condom use. The primary intention to use condoms as one means to prevent the spread of HIV is not principally contraceptive. For not recognizing the integral yet complex relationship between different levels if HIV prevention and treatment and care responses, they confuse their opposition to artificial contraception with a higher principle and commitment to preserve life. With their criticism they fail to understand the fundamental principles of health promotion. In the struggle against HIV/AIDS, as with so many issues, the Catholic Church must engage with those who are touching the problem. It is also an opportunity to begin a proper dialogue wherein diversity can be celebrated, and values of responsible choices can be shared.

  12. PSYCHOSOMATIC PROBLEMS IN UROLOGY

    PubMed Central

    Auerback, Alfred; Smith, Donald R.

    1952-01-01

    The intimate relationship between the urinary and genital systems permits stimuli in one system to influence the other. At least 15 per cent of women with symptoms of cystitis have no organic basis for their complaints. In psychiatric studies it has been noted that sexual conflict is the primary etiological factor in these patients. In some cases, continuance of the disorder leads to irreversible organic change. Urinary symptoms such as frequency, urgency, burning or retention are most common in women and become an automatic response to anxiety-provoking or sexual stimuli. In men, functional urinary symptoms are relatively infrequent. Often they indicate problems of genital dysfunction. Complaints of impotence, penile pain, testicular pain, or non-specific urethritis stem back to difficulties in their sexual lives. Many of the patients have symptoms of a generalized anxiety tension state due to sexual problems. A purely organic consideration of genitourinary disorders will lead to erroneous conclusions and unsatisfactory therapeutic results. The psychosomatic approach—that is, considering both physical and psychological aspects—will explain many hitherto difficult cases. PMID:14886756

  13. Microchip problems plague DOD

    NASA Astrophysics Data System (ADS)

    Smith, R. J.

    1984-10-01

    The major issues in the controversy over the discovery of millions of defective microchips sold to the DOD by the Texas Instruments (TI) corporation are outlined. Defects in the microcircuits are blamed on inadequate testing procedures performed by TI during manufacture, and on inadequate testing procedures used by a subcontractor especially contracted to test the chips. Because the problem persisted over a period of years, defects might be possible in as many as 100 million chips used in a broad range of military applications including the Trident submarine, the B-52, B-1B, F-15, F-111, F-4, A-6, and A-7 aircraft, the Harpoon and HARM missile systems, and the Space Shuttles Discovery and Challenger. It is pointed out that although TI has accepted responsibility for the defective chips, little will be done by the DOD to compel the company to replace them, or to upgrade testing procedures. It is concluded that the serious nature of the problem could renew interest in recommendations for the standardization of military microcircuits.

  14. Understanding the Problem. Problem Solving and Communication Activity Series. The Math Forum: Problems of the Week

    ERIC Educational Resources Information Center

    Math Forum @ Drexel, 2009

    2009-01-01

    Different techniques for understanding a problem can lead to ideas for never-used-before solutions. Good problem-solvers use a problem-solving strategy and may come back to it frequently while they are working on the problem to refine their strategy, see if they can find better solutions, or find other questions. Writing is an integral part of…

  15. Abstraction and Problem Reformulation

    NASA Technical Reports Server (NTRS)

    Giunchiglia, Fausto

    1992-01-01

    In work done jointly with Toby Walsh, the author has provided a sound theoretical foundation to the process of reasoning with abstraction (GW90c, GWS9, GW9Ob, GW90a). The notion of abstraction formalized in this work can be informally described as: (property 1), the process of mapping a representation of a problem, called (following historical convention (Sac74)) the 'ground' representation, onto a new representation, called the 'abstract' representation, which, (property 2) helps deal with the problem in the original search space by preserving certain desirable properties and (property 3) is simpler to handle as it is constructed from the ground representation by "throwing away details". One desirable property preserved by an abstraction is provability; often there is a relationship between provability in the ground representation and provability in the abstract representation. Another can be deduction or, possibly inconsistency. By 'throwing away details' we usually mean that the problem is described in a language with a smaller search space (for instance a propositional language or a language without variables) in which formulae of the abstract representation are obtained from the formulae of the ground representation by the use of some terminating rewriting technique. Often we require that the use of abstraction results in more efficient .reasoning. However, it might simply increase the number of facts asserted (eg. by allowing, in practice, the exploration of deeper search spaces or by implementing some form of learning). Among all abstractions, three very important classes have been identified. They relate the set of facts provable in the ground space to those provable in the abstract space. We call: TI abstractions all those abstractions where the abstractions of all the provable facts of the ground space are provable in the abstract space; TD abstractions all those abstractions wllere the 'unabstractions' of all the provable facts of the abstract space are

  16. The Brazil nut problem

    NASA Astrophysics Data System (ADS)

    Huerta, Dora; Ruiz-Suarez, Jesus

    2004-03-01

    The segregation of large intruders in a vertically vibrated granular bed is studied. We measure rising times a function of density, diameter and depth; for two different sinusoidal excitations. Our results shed definitive light to explain the fundamental aspects of the fascinating Brazil nut problem. At low frequencies (high amplitudes), inertia and convection are the only mechanisms behind segregation. Inertia dominates when the relative density of the intruder is greater than one and convection when it is less than one. At high frequencies (small amplitudes), where convection is suppressed, segregation occurs by buoyancy or sinkage. Finally, when the diameter of the intruders is changed, the well known paradigm "larger intruders rise faster" fails if the mass of the intruders is kept constant (while their relative densities are greater than one).

  17. Sleep problems in children.

    PubMed

    Baweja, R; Calhoun, S; Baweja, R; Singareddy, R

    2013-10-01

    Sleep complaints and sleep disorders are common during childhood and adolescence. The impact of not getting enough sleep may affect children's' physical health as well emotional, cognitive and social development. Insomnia, sleep-disordered breathing, parasomnias and sleep disturbances associated with medical and psychiatric disorders are some of the commonly encountered sleep disorders in this age group. Changes in sleep architecture and the amount of sleep requirement associated with each stage of development should be considered during an evaluation of sleep disorders in children. Behavioral treatments should be used initially wherever possible especially considering that most pharmacologic agents used to treat pediatric sleep disorders are off-label. In this review we address the most common sleep problems in children/adolescents as they relate to prevalence, presentation and symptoms, evaluation and management.

  18. The Microchp Scheduling Problem

    NASA Astrophysics Data System (ADS)

    Bosman, M. G. C.; Bakker, V.; Molderink, A.; Hurink, J. L.; Smit, G. J. M.

    2009-08-01

    The increasing penetration of renewable energy sources, the demand for more energy efficient electricity production and the increase in distributed electricity generation causes a shift in the way electricity is produced and consumed. The downside of these changes in the electricity grid is that network stability and controllability becomes more difficult compared to the old situation. The new network has to accommodate various means of production, consumption and buffering and needs to offer control over the energy flows between these three elements. In order to offer such a control mechanism we need to know more about the individual aspects. In this paper we focus on the modelling of distributed production. Especially we look at the use of microCHP (Combined Heat and Power) appliances in a group of houses. The problem of planning the production runs of the microCHP is modelled via an ILP formulation both for a single house and for a group of houses.

  19. Wicked Problem Solvers.

    PubMed

    Edmondson, Amy C

    2016-06-01

    Companies today increasingly rely on teams that span many industries for radical innovation, especially to solve "wicked problems." So leaders have to understand how to promote collaboration when roles are uncertain, goals are shifting, expertise and organizational cultures are varied, and participants have clashing or even antagonistic perspectives. HBS professor Amy Edmondson has studied more than a dozen cross-industry innovation projects, among them the creation of a new city, a mango supply-chain transformation, and the design and construction of leading-edge buildings. She has identified the leadership practices that make successful cross-industry teams work: fostering an adaptable vision, promoting psychological safety, enabling knowledge sharing, and encouraging collaborative innovation. Though these practices are broadly familiar, their application within cross-industry teams calls for unique leadership approaches that combine flexibility, open-mindedness, humility, and fierce resolve.

  20. [Hypersomnia: a diagnostic problem].

    PubMed

    Kranenburg, Guido; Teunissen, Laurien L

    2014-01-01

    Hypersomnia is a frequently occurring problem. When taking a medical history it is important to distinguish between fatigue and sleepiness. We present a 14-year-old girl with narcolepsy and a 59-year-old man with idiopathic hypersomnia. Features that are typical of narcolepsy are cataplexy and weight gain. Features that are typical of both narcolepsy and idiopathic hypersomnia are daytime naps, insomnia, sleep paralysis and hypnagogic hallucinations. Additional testing in patients with hypersomnia should include a polysomnography in order to exclude other sleeping disorders, and a mean sleep latency test. Practice shows that both patients with narcolepsy and those with idiopathic hypersomnia benefit from treatment with stimulating drugs such as modafinil.

  1. The unwitting sacrifice problem

    PubMed Central

    Gillett, G

    2005-01-01

    The diagnosis of bipolar disorder has been linked to giftedness of various sorts and this raises a special problem in that it is likely that the condition has a genetic basis. Therefore it seems possible that in the near future we will be able to detect and eliminate the gene predisposing to the disorder. This may mean, however, that, as a society, we lose the associated gifts. We might then face a difficult decision either way in that it is unclear that we are preventing an unalloyed bad when we diagnose and eliminate bipolar disorder through prenatal genetic testing and yet if we allow the individual to be born we are condemning that person to being an unwitting sacrifice in that they might well suffer considerable net distress as a result of our need to keep our gene pool enriched in the relevant way. PMID:15923479

  2. The Inhibiting Bisection Problem

    SciTech Connect

    Pinar, Ali; Fogel, Yonatan; Lesieutre, Bernard

    2006-12-18

    Given a graph where each vertex is assigned a generation orconsumption volume, we try to bisect the graph so that each part has asignificant generation/consumption mismatch, and the cutsize of thebisection is small. Our motivation comes from the vulnerability analysisof distribution systems such as the electric power system. We show thatthe constrained version of the problem, where we place either the cutsizeor the mismatch significance as a constraint and optimize the other, isNP-complete, and provide an integer programming formulation. We alsopropose an alternative relaxed formulation, which can trade-off betweenthe two objectives and show that the alternative formulation of theproblem can be solved in polynomial time by a maximum flow solver. Ourexperiments with benchmark electric power systems validate theeffectiveness of our methods.

  3. The Password Problem

    SciTech Connect

    Walkup, Elizabeth

    2016-06-01

    Passwords are an ubiquitous, established part of the Internet today, but they are also a huge security headache. Single sign-on, OAuth, and password managers are some of the solutions to this problem. OAuth is a new, popular method that allows people to use large, common authentication providers for many web applications. However, it comes at the expense of some privacy: OAuth makes users easy to track across websites, applications, and devices. Password managers put the power in the hands of the users, but this vulnerability survey reveals that you have to be extremely careful which program you choose. All in all, password managers are the solution of choice for home users and small organizations, but large companies will probably want to invest in their own SSO solutions.

  4. The worldwide "wildfire" problem.

    PubMed

    Gill, A Malcolm; Stephens, Scott L; Cary, Geoffrey J

    2013-03-01

    The worldwide "wildfire" problem is headlined by the loss of human lives and homes, but it applies generally to any adverse effects of unplanned fires, as events or regimes, on a wide range of environmental, social, and economic assets. The problem is complex and contingent, requiring continual attention to the changing circumstances of stakeholders, landscapes, and ecosystems; it occurs at a variety of temporal and spatial scales. Minimizing adverse outcomes involves controlling fires and fire regimes, increasing the resistance of assets to fires, locating or relocating assets away from the path of fires, and, as a probability of adverse impacts often remains, assisting recovery in the short-term while promoting the adaptation of societies in the long-term. There are short- and long-term aspects to each aspect of minimization. Controlling fires and fire regimes may involve fire suppression and fuel treatments such as prescribed burning or non-fire treatments but also addresses issues associated with unwanted fire starts like arson. Increasing the resistance of assets can mean addressing the design and construction materials of a house or the use of personal protective equipment. Locating or relocating assets can mean leaving an area about to be impacted by fire or choosing a suitable place to live; it can also mean the planning of land use. Assisting recovery and promoting adaptation can involve insuring assets and sharing responsibility for preparedness for an event. There is no single, simple, solution. Perverse outcomes can occur. The number of minimizing techniques used, and the breadth and depth of their application, depends on the geographic mix of asset types. Premises for policy consideration are presented.

  5. Computer Problem-Solving Coaches

    NASA Astrophysics Data System (ADS)

    Hsu, Leon; Heller, Kenneth

    2005-09-01

    Computers might be able to play an important role in physics instruction by coaching students to develop good problem-solving skills. Building on previous research on student problem solving and on designing computer programs to teach cognitive skills, we are developing a prototype computer coach to provide students with guided practice in solving problems. In addition to helping students become better problem solvers, such programs can be useful in studying how students learn to solve problems and how and if problem-solving skills can be transferred from a computer to a pencil-and-paper environment.

  6. Problem Solving through an Optimization Problem in Geometry

    ERIC Educational Resources Information Center

    Poon, Kin Keung; Wong, Hang-Chi

    2011-01-01

    This article adapts the problem-solving model developed by Polya to investigate and give an innovative approach to discuss and solve an optimization problem in geometry: the Regiomontanus Problem and its application to football. Various mathematical tools, such as calculus, inequality and the properties of circles, are used to explore and reflect…

  7. Adolescent Problem Behavior and Problem Driving in Young Adulthood

    ERIC Educational Resources Information Center

    Bingham, C. Raymond; Shope, Jean T.

    2004-01-01

    Motor vehicle crashes are the leading cause of death among drivers younger than age 35, making problem driving behavior among young drivers a significant public concern. Effective intervention requires a better understanding of the antecedents of problem driving. Problem behavior theory, social control theory, and Kandel's model of substance use…

  8. Problem Solvers: Problem--How Long Can You Stand?

    ERIC Educational Resources Information Center

    Teaching Children Mathematics, 2010

    2010-01-01

    Healthy lifestyles are increasingly emphasized these days. This month the authors begin a series of mathematical problems that also address physical activity. They hope that these problems offer opportunities to investigate mathematics and also reinforce the desire to lead a healthy life. In their first problem of the academic year, students…

  9. Developing Metacognitive and Problem-Solving Skills through Problem Manipulation

    ERIC Educational Resources Information Center

    Parker Siburt, Claire J.; Bissell, Ahrash N.; Macphail, Richard A.

    2011-01-01

    In a collaborative effort between the our university's department of chemistry and the academic resource center, we designed a model for general chemistry recitation based on a problem manipulation method in which students actively assess the skills and knowledge used to answer a chemical problem and then manipulate the problem to create a new…

  10. Representations in Problem Solving: A Case Study with Optimization Problems

    ERIC Educational Resources Information Center

    Villegas, Jose L.; Castro, Enrique; Gutierrez, Jose

    2009-01-01

    Introduction: Representations play an essential role in mathematical thinking. They favor the understanding of mathematical concepts and stimulate the development of flexible and versatile thinking in problem solving. Here our focus is on their use in optimization problems, a type of problem considered important in mathematics teaching and…

  11. Quantum Hall Effect of Massless Dirac Fermions and Free Fermions in Hofstadter's Butterfly

    NASA Astrophysics Data System (ADS)

    Yoshioka, Nobuyuki; Matsuura, Hiroyasu; Ogata, Masao

    2016-06-01

    We propose a new physical interpretation of the Diophantine equation of σxy for the Hofstadter problem. First, we divide the energy spectrum, or Hofstadter's butterfly, into smaller self-similar areas called "subcells", which were first introduced by Hofstadter to describe the recursive structure. We find that in the energy gaps between subcells, there are two ways to account for the quantization rule of σxy, that are consistent with the Diophantine equation: Landau quantization of (i) massless Dirac fermions or (ii) free fermions in Hofstadter's butterfly.

  12. Energy Problems and Environmental Concern

    ERIC Educational Resources Information Center

    Train, Russell E.

    1973-01-01

    Discusses problems encountered in energy extraction and consumption, involving nuclear power plant construction, environmental consequences of energy systems, and energy conservation ethics. Indicates that the increasing concern over environmental quality is not the true cause of present energy problems. (CC)

  13. Dementia - behavior and sleep problems

    MedlinePlus

    ... page: //medlineplus.gov/ency/patientinstructions/000029.htm Dementia - behavior and sleep problems To use the sharing features on this ... get to sleep and stay asleep Tips for Behavior and Sleep Problems Having a daily routine may help. Calmly ...

  14. The Problem of Defining Intelligence.

    ERIC Educational Resources Information Center

    Lubar, David

    1981-01-01

    The major philosophical issues surrounding the concept of intelligence are reviewed with respect to the problems surrounding the process of defining and developing artificial intelligence (AI) in computers. Various current definitions and problems with these definitions are presented. (MP)

  15. Sherlock Holmes, Master Problem Solver.

    ERIC Educational Resources Information Center

    Ballew, Hunter

    1994-01-01

    Shows the connections between Sherlock Holmes's investigative methods and mathematical problem solving, including observations, characteristics of the problem solver, importance of data, questioning the obvious, learning from experience, learning from errors, and indirect proof. (MKR)

  16. Decision Analysis for Environmental Problems

    EPA Science Inventory

    Environmental management problems are often complex and uncertain. A formal process with proper guidance is needed to understand the issues, identify sources of disagreement, and analyze the major uncertainties in environmental problems. This course will present a process that fo...

  17. Strengthening Programs through Problem Solving.

    ERIC Educational Resources Information Center

    Dyer, Jim

    1993-01-01

    Describes a secondary agricultural education program that was a dumping ground for academically disadvantaged students. Discusses how such a program can be improved by identifying problems and symptoms, treating problems, and goal setting. (JOW)

  18. Enhancing chemistry problem-solving achievement using problem categorization

    NASA Astrophysics Data System (ADS)

    Bunce, Diane M.; Gabel, Dorothy L.; Samuel, John V.

    The enhancement of chemistry students' skill in problem solving through problem categorization is the focus of this study. Twenty-four students in a freshman chemistry course for health professionals are taught how to solve problems using the explicit method of problem solving (EMPS) (Bunce & Heikkinen, 1986). The EMPS is an organized approach to problem analysis which includes encoding the information given in a problem (Given, Asked For), relating this to what is already in long-term memory (Recall), and planning a solution (Overall Plan) before a mathematical solution is attempted. In addition to the EMPS training, treatment students receive three 40-minute sessions following achievement tests in which they are taught how to categorize problems. Control students use this time to review the EMPS solutions of test questions. Although problem categorization is involved in one section of the EMPS (Recall), treatment students who received specific training in problem categorization demonstrate significantly higher achievement on combination problems (those problems requiring the use of more than one chemical topic for their solution) at (p = 0.01) than their counterparts. Significantly higher achievement for treatment students is also measured on an unannounced test (p = 0.02). Analysis of interview transcripts of both treatment and control students illustrates a Rolodex approach to problem solving employed by all students in this study. The Rolodex approach involves organizing equations used to solve problems on mental index cards and flipping through them, matching units given when a new problem is to be solved. A second phenomenon observed during student interviews is the absence of a link in the conceptual understanding of the chemical concepts involved in a problem and the problem-solving skills employed to correctly solve problems. This study shows that explicit training in categorization skills and the EMPS can lead to higher achievement in complex problem

  19. Identifying and managing problem drinkers.

    PubMed Central

    Kahan, M.

    1996-01-01

    Problem drinking is far more common than severe alcohol dependence and is associated with considerable morbidity and health care costs. Whereas patients with alcohol dependence respond best to intensive treatment, one or more brief sessions of physician advice and counseling reduces alcohol consumption among problem drinkers. The two most useful tools to identify problem drinkers are the CAGE and the drinking problem question. PMID:8653034

  20. Large Spectral Library Problem

    SciTech Connect

    Chilton, Lawrence K.; Walsh, Stephen J.

    2008-10-03

    Hyperspectral imaging produces a spectrum or vector at each image pixel. These spectra can be used to identify materials present in the image. In some cases, spectral libraries representing atmospheric chemicals or ground materials are available. The challenge is to determine if any of the library chemicals or materials exist in the hyperspectral image. The number of spectra in these libraries can be very large, far exceeding the number of spectral channels collected in the ¯eld. Suppose an image pixel contains a mixture of p spectra from the library. Is it possible to uniquely identify these p spectra? We address this question in this paper and refer to it as the Large Spectral Library (LSL) problem. We show how to determine if unique identi¯cation is possible for any given library. We also show that if p is small compared to the number of spectral channels, it is very likely that unique identi¯cation is possible. We show that unique identi¯cation becomes less likely as p increases.

  1. The lawnmower problem and other geometric path covering problems

    SciTech Connect

    Fekete, S.; Arkin, E.; Mitchell, J.

    1994-12-31

    We discuss the Lawnmower Problem: Given a polygonal region, find the shortest closed path along which we have to move a given object (typically a square or a circle), such that any point of the region will be covered by the object for some position of it movement. In another version of the problem, known as the Milling Problem, the object has to stay within the region at all times. Practical motivations for considering the Lawnmower Problem come from manufacturing (spray painting, quality control), geography (aerial surveys), optimization (tour planning for a large number of clients with limited mobility), and gardening. The Milling Problem has gained attention by its importance for NC pocket machining. We show that both problems are NP-hard and discuss approximation methods for various versions of the problem.

  2. Problem Analysis: Challenging All Learners

    ERIC Educational Resources Information Center

    Garcia, Katie; Davis, Alicia

    2013-01-01

    In this article, Garcia and Davis describe problem analysis as the process of examining a given mathematics exercise to find ways in which the problem can be modified and extended to create a richer learning opportunity for students. Students are often reluctant to attempt what they perceive to be higher-order thinking problems, but problem…

  3. Crustal growth: Some major problems

    NASA Technical Reports Server (NTRS)

    Arculus, R. J.

    1988-01-01

    Fundamental problems with models currently used to explain the genesis and evolution of continental crust were raised. These problems focus around the difficulty of generating the upper continental crust from a lower crustal or mantle protolith without leaving a very large, and so far undetected, volume of restite. No conclusive resolution to the problems was achieved.

  4. The Identity of Problem Solving

    ERIC Educational Resources Information Center

    Mamona-Downs, Joanna; Downs, Martin

    2005-01-01

    This paper raises issues motivated by considering the "identity" of problem solving. This means that we are concerned with how other mathematics education topics impinge on problem solving, and with themes that naturally arise within the problem-solving agenda. We claim that some of these issues need more attention by educational research, while…

  5. Common Infant and Newborn Problems

    MedlinePlus

    It is hard when your baby is sick. Common health problems in babies include colds, coughs, fevers, and vomiting. Babies also commonly have skin problems, like diaper rash or cradle cap. Many of these problems are ... are worried about your baby, call your health care provider right away.

  6. Migratory Farmworker Problems and Needs.

    ERIC Educational Resources Information Center

    McElroy, Robert C.

    Despite much publicity, hearings, legislative efforts, and other minor accomplishments in recent years, migrants are still one of the most disadvantaged and impoverished groups in the U.S. Among their problems is that they have neither the political, economic, nor other means of mitigating their problems. Some of their problems include uncertain…

  7. Problem Solving and Beginning Programming.

    ERIC Educational Resources Information Center

    McAllister, Alan

    Based on current models of problem solving within cognitive psychology, this study focused on the spontaneous problem solving strategies used by children as they first learned LOGO computer programming, and on strategy transformations that took place during the problem solving process. The research consisted of a six weeks programming training…

  8. Supporting Problem Solving in PBL

    ERIC Educational Resources Information Center

    Jonassen, David

    2011-01-01

    Although the characteristics of PBL (problem focused, student centered, self-directed, etc.) are well known, the components of a problem-based learning environment (PBLE) and the cognitive scaffolds necessary to support learning to solve different kinds of problems with different learners is less clear. This paper identifies the different…

  9. Euler's Three-Body Problem.

    ERIC Educational Resources Information Center

    Wild, Walter J.

    1980-01-01

    Discusses the simplest three-body problem, known as Euler's problem. The article, intended for students in the undergraduate mathematics and physics curricula, shows how the complex equations for a specific three-body problem can be solved on a small calculator. (HM)

  10. Technological Problem Solving: A Proposal.

    ERIC Educational Resources Information Center

    Waetjen, Walter B.

    Examination of newer technology education materials reveals two recurring themes: one relates to curriculum content, familiarizing students with technology, and another to a technique of classroom instruction, i.e., problem solving. A problem-solving framework for technical education has the following components: (1) define the problem; (2)…

  11. A taxonomy of inductive problems.

    PubMed

    Kemp, Charles; Jern, Alan

    2014-02-01

    Inductive inferences about objects, features, categories, and relations have been studied for many years, but there are few attempts to chart the range of inductive problems that humans are able to solve. We present a taxonomy of inductive problems that helps to clarify the relationships between familiar inductive problems such as generalization, categorization, and identification, and that introduces new inductive problems for psychological investigation. Our taxonomy is founded on the idea that semantic knowledge is organized into systems of objects, features, categories, and relations, and we attempt to characterize all of the inductive problems that can arise when these systems are partially observed. Recent studies have begun to address some of the new problems in our taxonomy, and future work should aim to develop unified theories of inductive reasoning that explain how people solve all of the problems in the taxonomy.

  12. The Association between Attention Problems and Internalizing and Externalizing Problems: The Mediating Role of Peer Problems

    ERIC Educational Resources Information Center

    Yip, Vania T.; Ang, Rebecca P.; Ooi, Yoon Phaik; Fung, Daniel S. S.; Mehrotra, Kala; Sung, Min; Lim, Choon Guan

    2013-01-01

    Background: The high prevalence of attention problems in children warrants concern, as it is a risk factor for internalizing and externalizing problems. There lies a need to understand possible factors that may mediate this link so that interventions may be targeted to alleviate these mediators and interrupt the link between attention problems and…

  13. Problem Reporting System

    NASA Technical Reports Server (NTRS)

    Potter, Don; Serian, Charles; Sweet, Robert; Sapir, Babak; Gamez, Enrique; Mays, David

    2008-01-01

    The Problem Reporting System (PRS) is a Web application, running on two Web servers (load-balanced) and two database servers (RAID-5), which establishes a system for submission, editing, and sharing of reports to manage risk assessment of anomalies identified in NASA's flight projects. PRS consolidates diverse anomaly-reporting systems, maintains a rich database set, and incorporates a robust engine, which allows tracking of any hardware, software, or paper process by configuring an appropriate life cycle. Global and specific project administration and setup tools allow lifecycle tailoring, along with customizable controls for user, e-mail, notifications, and more. PRS is accessible via the World Wide Web for authorized user at most any location. Upon successful log-in, the user receives a customizable window, which displays time-critical 'To Do' items (anomalies requiring the user s input before the system moves the anomaly to the next phase of the lifecycle), anomalies originated by the user, anomalies the user has addressed, and custom queries that can be saved for future use. Access controls exist depending on a user's role as system administrator, project administrator, user, or developer, and then, further by association with user, project, subsystem, company, or item with provisions for business-to-business exclusions, limitations on access according to the covert or overt nature of a given project, all with multiple layers of filtration, as needed. Reporting of metrics is built in. There is a provision for proxy access (in which the user may choose to grant one or more other users to view screens and perform actions as though they were the user, during any part of a tracking life cycle - especially useful during tight build schedules and vacations to keep things moving). The system also provides users the ability to have an anomaly link to or notify other systems, including QA Inspection Reports, Safety, GIDEP (Government-Industry Data Exchange Program

  14. [361 million problems].

    PubMed

    Livi Bacci, M

    1990-01-01

    changing from the basic subsistence and energy of Malthus's day, as are the factors of election and adaptation. In an increasingly interdependent world, the link between production and consumption of natural resources has become less obvious, so that signs of dangerous imbalances between population and resources may be overlooked. But the demographic problems of 1 region will increasingly affect all other regions.

  15. What is a problem?: On problem-oriented interdisciplinarity.

    PubMed

    Schmidt, Jan C

    2011-06-01

    Among others, the term "problem" plays a major role in the various attempts to characterize interdisciplinarity or transdisciplinarity, as used synonymously in this paper. Interdisciplinarity (ID) is regarded as "problem solving among science, technology and society" and as "problem orientation beyond disciplinary constraints" (cf. Frodeman et al.: The Oxford Handbook of Interdisciplinarity. Oxford University Press, Oxford, 2010). The point of departure of this paper is that the discourse and practice of ID have problems with the "problem". The objective here is to shed some light on the vague notion of "problem" in order to advocate a specific type of interdisciplinarity: problem-oriented interdisciplinarity. The outline is as follows: Taking an ex negativo approach, I will show what problem-oriented ID does not mean. Using references to well-established distinctions in philosophy of science, I will show three other types of ID that should not be placed under the umbrella term "problem-oriented ID": object-oriented ID ("ontology"), theory-oriented ID (epistemology), and method-oriented ID (methodology). Different philosophical thought traditions can be related to these distinguishable meanings. I will then clarify the notion of "problem" by looking at three systematic elements: an undesired (initial) state, a desired (goal) state, and the barriers in getting from the one to the other. These three elements include three related kinds of knowledge: systems, target, and transformation knowledge. This paper elaborates further methodological and epistemological elements of problem-oriented ID. It concludes by stressing that problem-oriented ID is the most needed as well as the most challenging type of ID.

  16. Resource Scarcity: Problems Technology Cannot Solve; Problems Technology Can Solve.

    ERIC Educational Resources Information Center

    Meadows, Dennis; Castle, Emery N.

    1979-01-01

    Lists resource problems technology can and cannot solve, and emphasizes the need for considering and restructuring the social environments and institutions as well as developing new technologies. (CK)

  17. Mathematical problem solving by analogy.

    PubMed

    Novick, L R; Holyoak, K J

    1991-05-01

    We report the results of 2 experiments and a verbal protocol study examining the component processes of solving mathematical word problems by analogy. College students first studied a problem and its solution, which provided a potential source for analogical transfer. Then they attempted to solve several analogous problems. For some problems, subjects received one of a variety of hints designed to reduce or eliminate the difficulty of some of the major processes hypothesized to be involved in analogical transfer. Our studies yielded 4 major findings. First, the process of mapping the features of the source and target problems and the process of adapting the source solution procedure for use in solving the target problem were clearly distinguished: (a) Successful mapping was found to be insufficient for successful transfer and (b) adaptation was found to be a major source of transfer difficulty. Second, we obtained direct evidence that schema induction is a natural consequence of analogical transfer. The schema was found to co-exist with the problems from which it was induced, and both the schema and the individual problems facilitated later transfer. Third, for our multiple-solution problems, the relation between analogical transfer and solution accuracy was mediated by the degree of time pressure exerted for the test problems. Finally, mathematical expertise was a significant predictor of analogical transfer, but general analogical reasoning ability was not. The implications of the results for models of analogical transfer and for instruction were considered.

  18. Diabetes and Sexual and Urologic Problems

    MedlinePlus

    ... Disease, & Other Dental Problems Diabetes & Sexual & Urologic Problems Diabetes & Sexual & Urologic Problems Troublesome bladder symptoms and changes ... early onset of these sexual and urologic problems. Diabetes and Sexual Problems Both men and women with ...

  19. Modeling Applied to Problem Solving

    NASA Astrophysics Data System (ADS)

    Pawl, Andrew; Barrantes, Analia; Pritchard, David E.

    2009-10-01

    Modeling Applied to Problem Solving (MAPS) is a pedagogy that helps students transfer instruction to problem solving in an expert-like manner. Declarative and Procedural syllabus content is organized and learned (not discovered) as a hierarchy of General Models. Students solve problems using an explicit Problem Modeling Rubric that begins with System, Interactions and Model (S.I.M.). System and Interactions are emphasized as the key to a strategic description of the system and the identification of the appropriate General Model to apply to the problem. We have employed the pedagogy in a three-week review course for students who received a D in mechanics. The course was assessed by a final exam retest as well as pre and post C-LASS surveys, yielding a one standard deviation improvement in the students' ability to solve final exam problems and a statistically significant positive shift in 7 of the 9 categories in the C-LASS.

  20. [Ethical problems in health care].

    PubMed

    Zácek, A

    1994-02-28

    Changes in the scale of values associated with society entering plural democracy caused as regards conceptual problems of health care some ethical doubts and objections. In the author's opinion the most important ones are: problems on the essence of health and mission of health policy, responsibility for health care, nature of health services under conditions of market economy, problems of the interpretation of right to health, health requirements and the importance of equity in advanced cultural societies.

  1. Student Constructs of Mathematical Problems: Problem Types, Achievement and Gender

    ERIC Educational Resources Information Center

    Chiu, Mei-Shiu; Yeh, Huei-Ming; Whitebread, David

    2014-01-01

    This study aims to understand students' constructs regarding mathematical problems. Fifty-one Taiwanese primary students' constructs are elicited using interviews with the repertory grid technique based on their responses to creative and non-creative problems. The results of qualitative data analysis show that students' initial constructs can be…

  2. Problem Solvers: Problem--Jesse's Train

    ERIC Educational Resources Information Center

    James, Julie; Steimle, Alice

    2014-01-01

    Persevering in problem solving and constructing and critiquing mathematical arguments are some of the mathematical practices included in the Common Core State Standards for Mathematics (CCSSI 2010). To solve unfamiliar problems, students must make sense of the situation and apply current knowledge. Teachers can present such opportunities by…

  3. Giant Story Problems: Reading Comprehension through Math Problem Solving.

    ERIC Educational Resources Information Center

    Goularte, Renee

    Primary students solve "oversized" story problems using drawings, equations, and written responses, helping them understand the links between the language of story problems and the numerical representations of matching equations. The activity also includes oral language and reflective writing, thus bringing together a variety of language…

  4. Pet Problems at Home: Pet Problems in the Community.

    ERIC Educational Resources Information Center

    Soltow, Willow

    1984-01-01

    Discusses problems of pets in the community, examining the community's role related to disruptive pets and pet overpopulation. Also discusses pet problems at home, offering advice on selecting a pet, meeting a pet's needs, and disciplining pets. Includes a list of books, films/filmstrips, teaching materials, and various instructional strategies.…

  5. Problem Solving Style, Creative Thinking, and Problem Solving Confidence

    ERIC Educational Resources Information Center

    Houtz, John C.; Selby, Edwin C.

    2009-01-01

    Forty-two undergraduate and graduate students completed VIEW: An Assessment of Problem Solving Style, the non-verbal Torrance Test Thinking Creatively with Pictures, and the Problem Solving Inventory (PSI). VIEW assesses individuals' orientation to change, manner of processing, and ways of deciding, while the Torrance test measures several…

  6. Collaborative Everyday Problem Solving: Interpersonal Relationships and Problem Dimensions

    ERIC Educational Resources Information Center

    Strough, Jonell; Patrick, Julie Hicks; Swenson, Lisa M.; Cheng, Suling; Barnes, Kristi A.

    2003-01-01

    Older adults' preferred partners for collaborative everyday problem solving and the types of everyday problems solved alone and with others were examined in a sample of community dwelling older adults (N = 112, M age = 71.86 yrs., SD = 5.92 yrs.). Family members (i.e., spouses, adult children) were the most frequently nominated partners for…

  7. The generalized pole assignment problem. [dynamic output feedback problems

    NASA Technical Reports Server (NTRS)

    Djaferis, T. E.; Mitter, S. K.

    1979-01-01

    Two dynamic output feedback problems for a linear, strictly proper system are considered, along with their interrelationships. The problems are formulated in the frequency domain and investigated in terms of linear equations over rings of polynomials. Necessary and sufficient conditions are expressed using genericity.

  8. Haplotyping Problem, A Clustering Approach

    SciTech Connect

    Eslahchi, Changiz; Sadeghi, Mehdi; Pezeshk, Hamid; Kargar, Mehdi; Poormohammadi, Hadi

    2007-09-06

    Construction of two haplotypes from a set of Single Nucleotide Polymorphism (SNP) fragments is called haplotype reconstruction problem. One of the most popular computational model for this problem is Minimum Error Correction (MEC). Since MEC is an NP-hard problem, here we propose a novel heuristic algorithm based on clustering analysis in data mining for haplotype reconstruction problem. Based on hamming distance and similarity between two fragments, our iterative algorithm produces two clusters of fragments; then, in each iteration, the algorithm assigns a fragment to one of the clusters. Our results suggest that the algorithm has less reconstruction error rate in comparison with other algorithms.

  9. Haplotyping Problem, A Clustering Approach

    NASA Astrophysics Data System (ADS)

    Eslahchi, Changiz; Sadeghi, Mehdi; Pezeshk, Hamid; Kargar, Mehdi; Poormohammadi, Hadi

    2007-09-01

    Construction of two haplotypes from a set of Single Nucleotide Polymorphism (SNP) fragments is called haplotype reconstruction problem. One of the most popular computational model for this problem is Minimum Error Correction (MEC). Since MEC is an NP-hard problem, here we propose a novel heuristic algorithm based on clustering analysis in data mining for haplotype reconstruction problem. Based on hamming distance and similarity between two fragments, our iterative algorithm produces two clusters of fragments; then, in each iteration, the algorithm assigns a fragment to one of the clusters. Our results suggest that the algorithm has less reconstruction error rate in comparison with other algorithms.

  10. Inverse problem in hydrogeology

    NASA Astrophysics Data System (ADS)

    Carrera, Jesús; Alcolea, Andrés; Medina, Agustín; Hidalgo, Juan; Slooten, Luit J.

    2005-03-01

    The state of the groundwater inverse problem is synthesized. Emphasis is placed on aquifer characterization, where modelers have to deal with conceptual model uncertainty (notably spatial and temporal variability), scale dependence, many types of unknown parameters (transmissivity, recharge, boundary conditions, etc.), nonlinearity, and often low sensitivity of state variables (typically heads and concentrations) to aquifer properties. Because of these difficulties, calibration cannot be separated from the modeling process, as it is sometimes done in other fields. Instead, it should be viewed as one step in the process of understanding aquifer behavior. In fact, it is shown that actual parameter estimation methods do not differ from each other in the essence, though they may differ in the computational details. It is argued that there is ample room for improvement in groundwater inversion: development of user-friendly codes, accommodation of variability through geostatistics, incorporation of geological information and different types of data (temperature, occurrence and concentration of isotopes, age, etc.), proper accounting of uncertainty, etc. Despite this, even with existing codes, automatic calibration facilitates enormously the task of modeling. Therefore, it is contended that its use should become standard practice. L'état du problème inverse des eaux souterraines est synthétisé. L'accent est placé sur la caractérisation de l'aquifère, où les modélisateurs doivent jouer avec l'incertitude des modèles conceptuels (notamment la variabilité spatiale et temporelle), les facteurs d'échelle, plusieurs inconnues sur différents paramètres (transmissivité, recharge, conditions aux limites, etc.), la non linéarité, et souvent la sensibilité de plusieurs variables d'état (charges hydrauliques, concentrations) des propriétés de l'aquifère. A cause de ces difficultés, le calibrage ne peut êtreséparé du processus de modélisation, comme c'est le

  11. How Social Problems Are Born.

    ERIC Educational Resources Information Center

    Glazer, Nathan

    1994-01-01

    Examines how social conditions can become social problems and argues that there are objective ways of determining the scale of a particular problem. The paper supports its argument through examinations of prohibition, the decline in tobacco consumption, and the war on drugs. (GLR)

  12. Problem Behaviors & Tourette Syndrome. Revised.

    ERIC Educational Resources Information Center

    Bruun, Ruth Dowling; And Others

    This pamphlet discusses behavioral problems which are sometimes associated with Tourette Syndrome (TS), along with suggestions for parents to help manage these behaviors. Consideration is given to the following problems: obsessive-compulsive symptoms; attention deficit hyperactivity disorder; aggressive and explosive behaviors; self-injurious…

  13. Problem Based Learning: Mystery Disease.

    ERIC Educational Resources Information Center

    Bohland, Mark A.

    This guide features a problem-based learning (PBL) unit specifically designed for student-centered learning of new and meaningful content on diseases. Students grapple with a complex and changing problem that requires higher level thinking skills in an environment in which students work both individually and in collaboration with others. Includes…

  14. Good Boys Are Problems Too!

    ERIC Educational Resources Information Center

    Warren, Simon

    2003-01-01

    The "problem" of boys' achievement in the United Kingdom has emerged as part of a policy response to a crisis in the post-war social settlement. Post-Fordism has become the dominant meta-policy of education reform in the United Kingdom, constituting both policy problems and solutions as gender-neutral. However, the economic and political…

  15. Is the Drug Problem Soluble?

    ERIC Educational Resources Information Center

    Jonas, Steven

    1989-01-01

    Concludes that the principle drug problems in the United States arise from the use of cigarette tobacco and alcoholic beverages. Identifies a drug culture as the persistent force in society that promotes drug use. Points out that the influence of the primary drug industries inhibit attempts to deal effectively with drug problems. (KO)

  16. Problem Solving & Comprehension. Fourth Edition.

    ERIC Educational Resources Information Center

    Whimbey, Arthur; Lochhead, Jack

    This book shows how to increase one's power to analyze and comprehend problems. First, it outlines and illustrates the methods that good problem solvers use in attacking complex ideas. Then it gives some practice in applying these methods to a variety of questions in comprehension and reasoning. Chapters include: (1) "Test Your Mind--See How…

  17. The Future Problem Solving Program.

    ERIC Educational Resources Information Center

    Crabbe, Anne B.

    1989-01-01

    Describes the Future Problem Solving Program, in which students from the U.S. and around the world are tackling some complex challenges facing society, ranging from acid rain to terrorism. The program uses a creative problem solving process developed for business and industry. A sixth-grade toxic waste cleanup project illustrates the process.…

  18. The Problems of Human Environment.

    ERIC Educational Resources Information Center

    United Nations, New York, NY.

    Presented is a summary of considerations Specialized Agencies within the United Nations have given to the problems of the human environment. Uppermost are the problems of pollution--air, water, noise, marine, radiation, food, pesticide--as well as those of economic and social concern, environmental health, and misuse of the environment. Agencies…

  19. A Problem on Optimal Transportation

    ERIC Educational Resources Information Center

    Cechlarova, Katarina

    2005-01-01

    Mathematical optimization problems are not typical in the classical curriculum of mathematics. In this paper we show how several generalizations of an easy problem on optimal transportation were solved by gifted secondary school pupils in a correspondence mathematical seminar, how they can be used in university courses of linear programming and…

  20. Pen Pals: Practicing Problem Solving

    ERIC Educational Resources Information Center

    Lampe, Kristen A.; Uselmann, Linda

    2008-01-01

    This article describes a semester-long pen-pal project in which preservice teachers composed mathematical problems and the middle school students worked for solutions. The college students assessed the solution and the middle school students provided feedback regarding the problem itself. (Contains 6 figures.)

  1. Creative Thinking and Problem Solving.

    ERIC Educational Resources Information Center

    Lacy, Grace

    The booklet considers the nature of creativity in children and examines classroom implications. Among the topics addressed are the following: theories about creativity; research; developments in brain research; the creative process; creative problem solving; the Structure of Intellect Problem Solving (SIPS) model; a rationale for creativity in the…

  2. Identifying problem and compulsive gamblers.

    PubMed Central

    van Es, R.

    2000-01-01

    OBJECTIVE: To present a meta-analysis of current research on the prevalence, identification, and treatment of problem and compulsive gamblers. QUALITY OF EVIDENCE: Problem and compulsive gambling was not a socio-scientific concern until the last two decades. Hence research on this topic is limited. The summary and analysis for this paper relied on computer searches of journal and news abstracts in addition to direct contact with organizations addressing the identification and treatment of compulsive gamblers. MAIN MESSAGE: An estimated 5% of those who gamble run into problems. About 1% of those who gamble are predicted to experience serious problems. Successful treatment of problem and compulsive gambling continues to be a challenge. Although cognitive therapy has been the favoured approach, a combination of several therapeutic approaches is advocated. CONCLUSIONS: Problem and compulsive gambling can present a real health threat. As with other addictions, treatment strategies continue to be a baffling social problem. Aware and informed physicians can have a pivotal role in the difficult process of identifying, acknowledging, and remediating problem and compulsive gambling. PMID:10907572

  3. Problem Solving through Paper Folding

    ERIC Educational Resources Information Center

    Wares, Arsalan

    2014-01-01

    The purpose of this article is to describe a couple of challenging mathematical problems that involve paper folding. These problem-solving tasks can be used to foster geometric and algebraic thinking among students. The context of paper folding makes some of the abstract mathematical ideas involved relatively concrete. When implemented…

  4. Geothermal Energy: Prospects and Problems

    ERIC Educational Resources Information Center

    Ritter, William W.

    1973-01-01

    An examination of geothermal energy as a means of increasing the United States power resources with minimal pollution problems. Developed and planned geothermal-electric power installations around the world, capacities, installation dates, etc., are reviewed. Environmental impact, problems, etc. are discussed. (LK)

  5. Difficulties in Genetics Problem Solving.

    ERIC Educational Resources Information Center

    Tolman, Richard R.

    1982-01-01

    Examined problem-solving strategies of 30 high school students as they solved genetics problems. Proposes a new sequence of teaching genetics based on results: meiosis, sex chromosomes, sex determination, sex-linked traits, monohybrid and dihybrid crosses (humans), codominance (humans), and Mendel's pea experiments. (JN)

  6. Do TEFL Articles Solve Problems?

    ERIC Educational Resources Information Center

    Edge, Julian

    1985-01-01

    Discusses the problem which English-as-a-foreign-language (EFL) teacher trainees who are nonnative English speakers have in reading articles about EFL teaching methods. As a solution to this problem, the author produced a worksheet for the students to fill in while reading the articles which followed Hoey's…

  7. Students' Problem Solving and Justification

    ERIC Educational Resources Information Center

    Glass, Barbara; Maher, Carolyn A.

    2004-01-01

    This paper reports on methods of students' justifications of their solution to a problem in the area of combinatorics. From the analysis of the problem solving of 150 students in a variety of settings from high-school to graduate study, four major forms of reasoning evolved: (1) Justification by Cases, (2) Inductive Argument, (3) Elimination…

  8. Addressing problems in complete dentures.

    PubMed

    LaBarre, Eugene; Giusti, Lola; Pitigoi-Aron, Gabriela

    2007-10-01

    The authors have compiled a set of solutions to the most common issues influencing the success of complete denture cases. A brief review and discussion of occlusal vertical dimension is presented, followed by a troubleshooting guide to problems such as inadequate retention and stability, discomfort, and other problems affecting treatment outcome.

  9. Representations of an Osmosis Problem.

    ERIC Educational Resources Information Center

    Zuckerman, June Trop

    1998-01-01

    Explores whether students with several years of high school science are able to represent an osmosis problem correctly. The study problem features a typical osmotic system with students expected to make a graph to show how the solution level in the stem of the funnel changes over time. (DDR)

  10. Problem Solving, Scaffolding and Learning

    ERIC Educational Resources Information Center

    Lin, Shih-Yin

    2012-01-01

    Helping students to construct robust understanding of physics concepts and develop good solving skills is a central goal in many physics classrooms. This thesis examine students' problem solving abilities from different perspectives and explores strategies to scaffold students' learning. In studies involving analogical problem solving…

  11. Historical problem areas lessons learned

    NASA Technical Reports Server (NTRS)

    Sackheim, Bob; Fester, Dale A.

    1991-01-01

    Historical problem areas in space transportation propulsion technology are identified in viewgraph form. Problem areas discussed include materials compatibility, contamination, pneumatic/feed system flow instabilities, instabilities in rocket engine combustion and fuel sloshing, exhaust plume interference, composite rocket nozzle failure, and freeze/thaw damage.

  12. The Cereal Box Problem Revisited.

    ERIC Educational Resources Information Center

    Wilkins, Jesse L. M.

    1999-01-01

    Investigates the cereal box problem using both an experimental and theoretical framework, and Monte Carlo methods. Using empirical data, students can discover patterns and relationships that help them understand the origin of the theoretical solution to the problem. Contains 17 references. (Author/ASK)

  13. Learning Impasses in Problem Solving

    NASA Technical Reports Server (NTRS)

    Hodgson, J. P. E.

    1992-01-01

    Problem Solving systems customarily use backtracking to deal with obstacles that they encounter in the course of trying to solve a problem. This paper outlines an approach in which the possible obstacles are investigated prior to the search for a solution. This provides a solution strategy that avoids backtracking.

  14. The three-body problem.

    PubMed

    Musielak, Z E; Quarles, B

    2014-06-01

    The three-body problem, which describes three masses interacting through Newtonian gravity without any restrictions imposed on the initial positions and velocities of these masses, has attracted the attention of many scientists for more than 300 years. In this paper, we present a review of the three-body problem in the context of both historical and modern developments. We describe the general and restricted (circular and elliptic) three-body problems, different analytical and numerical methods of finding solutions, methods for performing stability analysis and searching for periodic orbits and resonances. We apply the results to some interesting problems of celestial mechanics. We also provide a brief presentation of the general and restricted relativistic three-body problems, and discuss their astronomical applications.

  15. Trigonometric problem cases well solved

    NASA Astrophysics Data System (ADS)

    Schröer, H.

    2001-10-01

    Content of the book are trigonometric problems that can be found scarely in the technical literature. It begins with using trigonometric functions to horizon and height. Interesting pure mathematical problems about tangent, inscribed tetragon and parallelogram follow. In chapter 6 is a generalization of Euclid's theorem fo the right-angled triangle. The next themes are exterior circle and incircle. In chapter 9 an unusual proof of the cosine law for sides is given. Further treated problems are the distance of two stars and eclipses. The aim group consists of mathematicians, natural scientists and technicians(also teacher) who have to do professionally with trigonometric problems and (or)who are interested in trigonometric problems. There is an english and a german edition.

  16. Ten Problems in Experimental Mathematics

    SciTech Connect

    Bailey, David H.; Borwein, Jonathan M.; Kapoor, Vishaal; Weisstein, Eric

    2004-09-30

    This article was stimulated by the recent SIAM ''100 DigitChallenge'' of Nick Trefethen, beautifully described in a recent book. Indeed, these ten numeric challenge problems are also listed in a recent book by two of present authors, where they are followed by the ten symbolic/numeric challenge problems that are discussed in this article. Our intent was to present ten problems that are characteristic of the sorts of problems that commonly arise in ''experimental mathematics''. The challenge in each case is to obtain a high precision numeric evaluation of the quantity, and then, if possible, to obtain a symbolic answer, ideally one with proof. Our goal in this article is to provide solutions to these ten problems, and in the process present a concise account of how one combines symbolic and numeric computation, which may be termed ''hybrid computation'', in the process of mathematical discovery.

  17. Sediment problems in urban areas

    USGS Publications Warehouse

    Guy, Harold P.

    1970-01-01

    One obstacle to a scientific recognition and an engineering solution to sediment-related environmental problems is that such problems are bound in conflicting and generally undefinable political and institutional restraints. Also, some of the difficulty may involve the fact that the scientist or engineer, because of his relatively narrow field of investigation, cannot always completely envision the less desirable effects of his work and communicate alternative solutions to the public. For example, the highway and motor-vehicle engineers have learned how to provide the means by which one can transport himself from one point to another with such great efficiency that a person's employment in this country is now commonly more than 5 miles from his residence. However, providing such efficient personal transport has created numerous serious environmental problems. Obstacles to recognition of and action to control sediment problems in and around urban areas are akin to other environmental problems with respect to the many scientific, engineering, economic, and social aspects.

  18. Some problems on the classical n-body problem

    NASA Astrophysics Data System (ADS)

    Albouy, Alain; Cabral, Hildeberto E.; Santos, Alan A.

    2012-08-01

    Our idea is to imitate Smale's list of problems, in a restricted domain of mathematical aspects of Celestial Mechanics. All the problems are on the n-body problem, some with different homogeneity of the potential, addressing many aspects such as central configurations, stability of relative equilibrium, singularities, integral manifolds, etc. Following Steve Smale in his list, the criteria for our selection are: (1) Simple statement. Also preferably mathematically precise, and best even with a yes or no answer. (2) Personal acquaintance with the problem, having found it not easy. (3) A belief that the question, its solution, partial results or even attempts at its solution are likely to have great importance for the development of the mathematical aspects of Celestial Mechanics.

  19. Problem solving stages in the five square problem.

    PubMed

    Fedor, Anna; Szathmáry, Eörs; Öllinger, Michael

    2015-01-01

    According to the restructuring hypothesis, insight problem solving typically progresses through consecutive stages of search, impasse, insight, and search again for someone, who solves the task. The order of these stages was determined through self-reports of problem solvers and has never been verified behaviorally. We asked whether individual analysis of problem solving attempts of participants revealed the same order of problem solving stages as defined by the theory and whether their subjective feelings corresponded to the problem solving stages they were in. Our participants tried to solve the Five-Square problem in an online task, while we recorded the time and trajectory of their stick movements. After the task they were asked about their feelings related to insight and some of them also had the possibility of reporting impasse while working on the task. We found that the majority of participants did not follow the classic four-stage model of insight, but had more complex sequences of problem solving stages, with search and impasse recurring several times. This means that the classic four-stage model is not sufficient to describe variability on the individual level. We revised the classic model and we provide a new model that can generate all sequences found. Solvers reported insight more often than non-solvers and non-solvers reported impasse more often than solvers, as expected; but participants did not report impasse more often during behaviorally defined impasse stages than during other stages. This shows that impasse reports might be unreliable indicators of impasse. Our study highlights the importance of individual analysis of problem solving behavior to verify insight theory.

  20. Problem solving stages in the five square problem

    PubMed Central

    Fedor, Anna; Szathmáry, Eörs; Öllinger, Michael

    2015-01-01

    According to the restructuring hypothesis, insight problem solving typically progresses through consecutive stages of search, impasse, insight, and search again for someone, who solves the task. The order of these stages was determined through self-reports of problem solvers and has never been verified behaviorally. We asked whether individual analysis of problem solving attempts of participants revealed the same order of problem solving stages as defined by the theory and whether their subjective feelings corresponded to the problem solving stages they were in. Our participants tried to solve the Five-Square problem in an online task, while we recorded the time and trajectory of their stick movements. After the task they were asked about their feelings related to insight and some of them also had the possibility of reporting impasse while working on the task. We found that the majority of participants did not follow the classic four-stage model of insight, but had more complex sequences of problem solving stages, with search and impasse recurring several times. This means that the classic four-stage model is not sufficient to describe variability on the individual level. We revised the classic model and we provide a new model that can generate all sequences found. Solvers reported insight more often than non-solvers and non-solvers reported impasse more often than solvers, as expected; but participants did not report impasse more often during behaviorally defined impasse stages than during other stages. This shows that impasse reports might be unreliable indicators of impasse. Our study highlights the importance of individual analysis of problem solving behavior to verify insight theory. PMID:26300794

  1. Optimization and geophysical inverse problems

    SciTech Connect

    Barhen, J.; Berryman, J.G.; Borcea, L.; Dennis, J.; de Groot-Hedlin, C.; Gilbert, F.; Gill, P.; Heinkenschloss, M.; Johnson, L.; McEvilly, T.; More, J.; Newman, G.; Oldenburg, D.; Parker, P.; Porto, B.; Sen, M.; Torczon, V.; Vasco, D.; Woodward, N.B.

    2000-10-01

    A fundamental part of geophysics is to make inferences about the interior of the earth on the basis of data collected at or near the surface of the earth. In almost all cases these measured data are only indirectly related to the properties of the earth that are of interest, so an inverse problem must be solved in order to obtain estimates of the physical properties within the earth. In February of 1999 the U.S. Department of Energy sponsored a workshop that was intended to examine the methods currently being used to solve geophysical inverse problems and to consider what new approaches should be explored in the future. The interdisciplinary area between inverse problems in geophysics and optimization methods in mathematics was specifically targeted as one where an interchange of ideas was likely to be fruitful. Thus about half of the participants were actively involved in solving geophysical inverse problems and about half were actively involved in research on general optimization methods. This report presents some of the topics that were explored at the workshop and the conclusions that were reached. In general, the objective of a geophysical inverse problem is to find an earth model, described by a set of physical parameters, that is consistent with the observational data. It is usually assumed that the forward problem, that of calculating simulated data for an earth model, is well enough understood so that reasonably accurate synthetic data can be generated for an arbitrary model. The inverse problem is then posed as an optimization problem, where the function to be optimized is variously called the objective function, misfit function, or fitness function. The objective function is typically some measure of the difference between observational data and synthetic data calculated for a trial model. However, because of incomplete and inaccurate data, the objective function often incorporates some additional form of regularization, such as a measure of smoothness

  2. Civil law problems and morbidity

    PubMed Central

    Pleasence, P; Balmer, N; Buck, A; O'Grady, A; Genn, H

    2004-01-01

    Study objective: In the United Kingdom, recognition of the links between social and health problems has led to government initiatives such as health action zones. The principles of civil law apply to many types of social problem, and the civil justice system provides one means through which they can be tackled. However, little research has been undertaken into the particular links between problems to which civil legal principles and processes can be applied and morbidity. This study examines these links, and the role of legal advice and services in preventing ill health. Design: This study examined survey respondents' self reports of longstanding illness/disability and experience of 18 problems to which legal principles can be applied. Setting: A random national survey conducted across England and Wales. Participants: 5611 adults drawn from 3348 residential households. Main results: Significant associations were found between illness/disability and 13 of the problem types. Moreover, experience of greater numbers of problems increased the likelihood of reported illness/disability. In attempting to resolve problems respondents' health also frequently suffered. Conclusions: This study highlights the contribution that public legal education and legal advice can make to the promotion of public health, and the importance of further integration of health and civil justice initiatives through health action zones, community legal service partnerships, etc, to further this end. PMID:15194714

  3. General aviation IFR operational problems

    NASA Technical Reports Server (NTRS)

    Bolz, E. H.; Eisele, J. E.

    1979-01-01

    Operational problems of general aviation IFR operators (particularly single pilot operators) were studied. Several statistical bases were assembled and utilized to identify the more serious problems and to demonstrate their magnitude. These bases include official activity projections, historical accident data and delay data, among others. The GA operating environment and cockpit environment were analyzed in detail. Solutions proposed for each of the problem areas identified are based on direct consideration of currently planned enhancements to the ATC system, and on a realistic assessment of the present and future limitations of general aviation avionics. A coordinated set of research program is suggested which would provide the developments necessary to implement the proposed solutions.

  4. Robot, computer problem solving system

    NASA Technical Reports Server (NTRS)

    Becker, J. D.

    1972-01-01

    The development of a computer problem solving system is reported that considers physical problems faced by an artificial robot moving around in a complex environment. Fundamental interaction constraints with a real environment are simulated for the robot by visual scan and creation of an internal environmental model. The programming system used in constructing the problem solving system for the simulated robot and its simulated world environment is outlined together with the task that the system is capable of performing. A very general framework for understanding the relationship between an observed behavior and an adequate description of that behavior is included.

  5. Problems in nonlinear resistive MHD

    SciTech Connect

    Turnbull, A.D.; Strait, E.J.; La Haye, R.J.; Chu, M.S.; Miller, R.L.

    1998-12-31

    Two experimentally relevant problems can relatively easily be tackled by nonlinear MHD codes. Both problems require plasma rotation in addition to the nonlinear mode coupling and full geometry already incorporated into the codes, but no additional physics seems to be crucial. These problems discussed here are: (1) nonlinear coupling and interaction of multiple MHD modes near the B limit and (2) nonlinear coupling of the m/n = 1/1 sawtooth mode with higher n gongs and development of seed islands outside q = 1.

  6. Customer-centered problem solving.

    PubMed

    Samelson, Q B

    1999-11-01

    If there is no single best way to attract new customers and retain current customers, there is surely an easy way to lose them: fail to solve the problems that arise in nearly every buyer-supplier relationship, or solve them in an unsatisfactory manner. Yet, all too frequently, companies do just that. Either we deny that a problem exists, we exert all our efforts to pin the blame elsewhere, or we "Band-Aid" the problem instead of fixing it, almost guaranteeing that we will face it again and again.

  7. The Soccer-Ball Problem

    NASA Astrophysics Data System (ADS)

    Hossenfelder, Sabine

    2014-07-01

    The idea that Lorentz-symmetry in momentum space could be modified but still remain observer-independent has received quite some attention in the recent years. This modified Lorentz-symmetry, which has been argued to arise in Loop Quantum Gravity, is being used as a phenomenological model to test possibly observable effects of quantum gravity. The most pressing problem in these models is the treatment of multi-particle states, known as the 'soccer-ball problem'. This article briefly reviews the problem and the status of existing solution attempts.

  8. [Ethical problems in organ transplantation].

    PubMed

    Valenta, J; Treska, V; Hasman, D

    1999-02-01

    Organ transplantation is an accepted therapeutic method with good results, but it is connected with many not only medical but also ethical problems. One of the most important problems is the donor programme. In cadaverous donors the main ethical and legal question is the decision who can issue the consent with organ retrieval; in living donors it is the problem of motivation and financial compensation. Allocation of organs with low compatibility or from non-ideal donors, and the recipient's consent in these cases may involve difficult decisions.

  9. Understanding Heart Valve Problems and Causes

    MedlinePlus

    ... affecting the aortic valve, and can lead to aortic stenosis . Mediastinal radiation therapy (radiation to the chest) – Studies ... Disease "Innocent" Heart Murmur Problem: Valve Stenosis - Problem: Aortic Valve Stenosis - Problem: Mitral Valve Stenosis - Problem: Tricuspid Valve Stenosis - ...

  10. Late Blooming or Language Problem?

    MedlinePlus

    ... and Swallowing / Disorders and Diseases Late Blooming or Language Problem? Parents are smart. They listen to their ... or not their child is developing speech and language at a normal rate. If parents think that ...

  11. Problems in Recording the Electrocardiogram.

    ERIC Educational Resources Information Center

    Webster, John G.

    The unwanted signals that arise in electrocardiography are discussed. A technical background of electrocardiography is given, along with teaching techniques that educate students of medical instrumentation to solve the problems caused by these signals. (MJH)

  12. The unsolved problems of neuroscience

    PubMed Central

    Adolphs, Ralph

    2015-01-01

    Some problems in neuroscience are nearly solved. For others, solutions are decades away. The current pace of advances in methods forces us to take stock, to ask where we are going, and what we should research next. PMID:25703689

  13. Chemical Educators Mull Problems, Needs

    ERIC Educational Resources Information Center

    O'Sullivan, Dermot A.

    1977-01-01

    Discusses the international symposium on chemical education held in Ljubljana, Yugoslavia, August, 1977. Included are the symposium's recommendations for future international action relating to the problems and needs of chemical education. (SL)

  14. Solving a problem by analogy

    NASA Astrophysics Data System (ADS)

    Easton, Don

    1999-03-01

    This note is a description of a student solution to a problem. I found the solution exciting because it exemplifies the kind of solution by analogy that Feynman describes in The Feynman Lectures on Physics.

  15. Warning Signs of Breastfeeding Problems

    MedlinePlus

    ... Page Content Article Body Natural as the breastfeeding process is, problems can occasionally arise. When they do surface, they may grow worse very quickly and interfere with your milk production or your baby’s ability to get the nutrition ...

  16. Surrogate Guderley Test Problem Definition

    SciTech Connect

    Ramsey, Scott D.; Shashkov, Mikhail J.

    2012-07-06

    The surrogate Guderley problem (SGP) is a 'spherical shock tube' (or 'spherical driven implosion') designed to ease the notoriously subtle initialization of the true Guderley problem, while still maintaining a high degree of fidelity. In this problem (similar to the Guderley problem), an infinitely strong shock wave forms and converges in one-dimensional (1D) cylindrical or spherical symmetry through a polytropic gas with arbitrary adiabatic index {gamma}, uniform density {rho}{sub 0}, zero velocity, and negligible pre-shock pressure and specific internal energy (SIE). This shock proceeds to focus on the point or axis of symmetry at r = 0 (resulting in ostensibly infinite pressure, velocity, etc.) and reflect back out into the incoming perturbed gas.

  17. Problem Solving with General Semantics.

    ERIC Educational Resources Information Center

    Hewson, David

    1996-01-01

    Discusses how to use general semantics formulations to improve problem solving at home or at work--methods come from the areas of artificial intelligence/computer science, engineering, operations research, and psychology. (PA)

  18. Student Problem-Solving Behaviors

    NASA Astrophysics Data System (ADS)

    Harper, Kathleen A.

    2006-04-01

    Kathy Harper is director of undergraduate curriculum development in the physics department at The Ohio State University. She has been involved in local and national workshops for in-service teachers and conducts research in student problem solving.

  19. Corrosion Problems in Absorption Chillers

    ERIC Educational Resources Information Center

    Stetson, Bruce

    1978-01-01

    Absorption chillers use a lithium bromide solution as the medium of absorption and water as the refrigerant. Discussed are corrosion and related problems, tests and remedies, and cleaning procedures. (Author/MLF)

  20. Systems management techniques and problems

    NASA Technical Reports Server (NTRS)

    1971-01-01

    Report is reviewed which discusses history and trends of systems management, its basic principles, and nature of problems that lend themselves to systems approach. Report discusses systems engineering as applied to weapons acquisition, ecology, patient monitoring, and retail merchandise operations.

  1. Medical Tests for Prostate Problems

    MedlinePlus

    ... walnut-shaped gland that is part of the male reproductive system. It has two or more lobes, or sections, ... treating problems of the urinary tract and the male reproductive system. Abdominal Ultrasound Ultrasound uses a device, called a ...

  2. Special Medical Problems of Athletes.

    ERIC Educational Resources Information Center

    Couch, Joan M.

    1987-01-01

    This article addresses the situations in which athletes with special needs and considerations participate in sports. The health problems discussed are diabetes mellitus, exercise-induced asthma, exercise-induced anaphylaxis, and epilepsy. (MT)

  3. Enteral nutrition - child - managing problems

    MedlinePlus

    ... page: //medlineplus.gov/ency/patientinstructions/000164.htm Enteral nutrition - child - managing problems To use the sharing features ... trouble breathing, call 911. References Mcclave SA. Enteral nutrition. In: Goldman L, Schafer AI, eds. Goldman-Cecil ...

  4. Spectral methods for discontinuous problems

    NASA Technical Reports Server (NTRS)

    Abarbanel, S.; Gottlieb, D.; Tadmor, E.

    1985-01-01

    Spectral methods yield high-order accuracy even when applied to problems with discontinuities, though not in the sense of pointwise accuracy. Two different procedures are presented which recover pointwise accurate approximations from the spectral calculations.

  5. Eldercare at Home: Skin Problems

    MedlinePlus

    ... body oil, or moisturizer that is high in petroleum (AquaphorTM, EucerinTM). Avoid moisturizers with perfume or alcohol ... or DoveTM. Make sure you rinse well. Use petroleum jelly For problem dry spots, apply petroleum jelly ...

  6. Dental Health and Orthodontic Problems

    MedlinePlus

    ... patients is cosmetic. Beside the traditional silver-colored metal alloy used to fill cavities, a composite material ... Orthodontic Problems are Treated If you were a “metal mouth” as a teenager, you’ll immediately notice ...

  7. Quantum Computing: Solving Complex Problems

    ScienceCinema

    DiVincenzo, David [IBM Watson Research Center

    2016-07-12

    One of the motivating ideas of quantum computation was that there could be a new kind of machine that would solve hard problems in quantum mechanics. There has been significant progress towards the experimental realization of these machines (which I will review), but there are still many questions about how such a machine could solve computational problems of interest in quantum physics. New categorizations of the complexity of computational problems have now been invented to describe quantum simulation. The bad news is that some of these problems are believed to be intractable even on a quantum computer, falling into a quantum analog of the NP class. The good news is that there are many other new classifications of tractability that may apply to several situations of physical interest.

  8. The Mind-Body Problem.

    ERIC Educational Resources Information Center

    Fodor, Jerry A.

    1981-01-01

    Describes several different philosophies of mind with each philosophy's explanation of the mind-body problem. Philosophies discussed include dualism, materialism, functionalism, radical behaviorism, logical behaviorism and central-state identity. (DS)

  9. Families and Pediatric Feeding Problems

    ERIC Educational Resources Information Center

    Martorana, Pamela; Bove, Kelly; Scarcelli, Melissa

    2008-01-01

    When a child is born with a feeding and/or swallowing problem, it affects the entire family. Parents, mothers specifically, internalize the problem and come to believe it is due to something they've done. Families are put on an emotional rollercoaster with the ups and downs being dependant on how much the child has eaten that day. In this article,…

  10. Inversion Algorithms for Geophysical Problems

    DTIC Science & Technology

    1987-12-16

    ktdud* Sccumy Oass/Kjoon) Inversion Algorithms for Geophysical Problems (U) 12. PERSONAL AUTHOR(S) Lanzano, Paolo 13 «. TYPE OF REPORT Final 13b...spectral density. 20. DISTRIBUTION/AVAILABILITY OF ABSTRACT 13 UNCLASSIFIED/UNLIMITED D SAME AS RPT n OTIC USERS 22a. NAME OF RESPONSIBLE...Research Laboratory ’^^ SSZ ’.Washington. DC 20375-5000 NRLrMemorandum Report-6138 Inversion Algorithms for Geophysical Problems p. LANZANO Space

  11. Free boundary problems in biology.

    PubMed

    Friedman, Avner

    2015-09-13

    In this paper, I review several free boundary problems that arise in the mathematical modelling of biological processes. The biological topics are quite diverse: cancer, wound healing, biofilms, granulomas and atherosclerosis. For each of these topics, I describe the biological background and the mathematical model, and then proceed to state mathematical results, including existence and uniqueness theorems, stability and asymptotic limits, and the behaviour of the free boundary. I also suggest, for each of the topics, open mathematical problems.

  12. Controversies in Obstetrics: Dermatologic Problems

    PubMed Central

    Barber, Kirk A.

    1988-01-01

    Skin disease in pregnancy generally produces increased concern among attending physicians. Not only is the diagnosis often a problem but the safety of the therapy may also be a concern. The author of this article presents three common skin problems and their treatments to illustrate the general principles used in diagnosis and treatment of skin disease during pregnancy. ImagesFigure 1Figure 2 PMID:21253230

  13. Leisure Time Problems and Livability

    DTIC Science & Technology

    1979-09-30

    satisfaction and for which they received recognition. Housing livability required at least adequate shelter, warmth , safety, minimal conveniences, access to work... judgements are based on preconceived attitudes; others are based on peer group hearsay before arrival and the remainder are formed in the first few weeks after...handicaps including weight, height, physique, skin coloration or complexion, health, beauty, speech problems, domestic problems, limited interpersonal

  14. The Consistent Vehicle Routing Problem

    SciTech Connect

    Groer, Christopher S; Golden, Bruce; Edward, Wasil

    2009-01-01

    In the small package shipping industry (as in other industries), companies try to differentiate themselves by providing high levels of customer service. This can be accomplished in several ways, including online tracking of packages, ensuring on-time delivery, and offering residential pickups. Some companies want their drivers to develop relationships with customers on a route and have the same drivers visit the same customers at roughly the same time on each day that the customers need service. These service requirements, together with traditional constraints on vehicle capacity and route length, define a variant of the classical capacitated vehicle routing problem, which we call the consistent VRP (ConVRP). In this paper, we formulate the problem as a mixed-integer program and develop an algorithm to solve the ConVRP that is based on the record-to-record travel algorithm. We compare the performance of our algorithm to the optimal mixed-integer program solutions for a set of small problems and then apply our algorithm to five simulated data sets with 1,000 customers and a real-world data set with more than 3,700 customers. We provide a technique for generating ConVRP benchmark problems from vehicle routing problem instances given in the literature and provide our solutions to these instances. The solutions produced by our algorithm on all problems do a very good job of meeting customer service objectives with routes that have a low total travel time.

  15. A Diagnostic Taxonomy of Adult Career Problems.

    ERIC Educational Resources Information Center

    Campbell, Robert E.; Cellini, James V.

    1981-01-01

    Developed a taxonomy for the differential diagnosis of adult career development problems. Problem categories identified were: (1) problems in career decision making; (2) problems in implementing career plans; (3) problems in organizational/institutional performance; and (4) problems in organizational/institutional adaption. (Author)

  16. Vehicle routing problem and capacitated vehicle routing problem frameworks in fund allocation problem

    NASA Astrophysics Data System (ADS)

    Mamat, Nur Jumaadzan Zaleha; Jaaman, Saiful Hafizah; Ahmad, Rokiah@Rozita

    2016-11-01

    Two new methods adopted from methods commonly used in the field of transportation and logistics are proposed to solve a specific issue of investment allocation problem. Vehicle routing problem and capacitated vehicle routing methods are applied to optimize the fund allocation of a portfolio of investment assets. This is done by determining the sequence of the assets. As a result, total investment risk is minimized by this sequence.

  17. Approximating random quantum optimization problems

    NASA Astrophysics Data System (ADS)

    Hsu, B.; Laumann, C. R.; Läuchli, A. M.; Moessner, R.; Sondhi, S. L.

    2013-06-01

    We report a cluster of results regarding the difficulty of finding approximate ground states to typical instances of the quantum satisfiability problem k-body quantum satisfiability (k-QSAT) on large random graphs. As an approximation strategy, we optimize the solution space over “classical” product states, which in turn introduces a novel autonomous classical optimization problem, PSAT, over a space of continuous degrees of freedom rather than discrete bits. Our central results are (i) the derivation of a set of bounds and approximations in various limits of the problem, several of which we believe may be amenable to a rigorous treatment; (ii) a demonstration that an approximation based on a greedy algorithm borrowed from the study of frustrated magnetism performs well over a wide range in parameter space, and its performance reflects the structure of the solution space of random k-QSAT. Simulated annealing exhibits metastability in similar “hard” regions of parameter space; and (iii) a generalization of belief propagation algorithms introduced for classical problems to the case of continuous spins. This yields both approximate solutions, as well as insights into the free energy “landscape” of the approximation problem, including a so-called dynamical transition near the satisfiability threshold. Taken together, these results allow us to elucidate the phase diagram of random k-QSAT in a two-dimensional energy-density-clause-density space.

  18. Computational problems in Arctic Research

    NASA Astrophysics Data System (ADS)

    Petrov, I.

    2016-02-01

    This article is to inform about main problems in the area of Arctic shelf seismic prospecting and exploitation of the Northern Sea Route: simulation of the interaction of different ice formations (icebergs, hummocks, and drifting ice floes) with fixed ice-resistant platforms; simulation of the interaction of icebreakers and ice- class vessels with ice formations; modeling of the impact of the ice formations on the underground pipelines; neutralization of damage for fixed and mobile offshore industrial structures from ice formations; calculation of the strength of the ground pipelines; transportation of hydrocarbons by pipeline; the problem of migration of large ice formations; modeling of the formation of ice hummocks on ice-resistant stationary platform; calculation the stability of fixed platforms; calculation dynamic processes in the water and air of the Arctic with the processing of data and its use to predict the dynamics of ice conditions; simulation of the formation of large icebergs, hummocks, large ice platforms; calculation of ridging in the dynamics of sea ice; direct and inverse problems of seismic prospecting in the Arctic; direct and inverse problems of electromagnetic prospecting of the Arctic. All these problems could be solved by up-to-date numerical methods, for example, using grid-characteristic method.

  19. The Problem of Assessing Problem Solving: Can Comparative Judgement Help?

    ERIC Educational Resources Information Center

    Jones, Ian; Inglis, Matthew

    2015-01-01

    School mathematics examination papers are typically dominated by short, structured items that fail to assess sustained reasoning or problem solving. A contributory factor to this situation is the need for student work to be marked reliably by a large number of markers of varied experience and competence. We report a study that tested an…

  20. Solving Optimization Problems with Dynamic Geometry Software: The Airport Problem

    ERIC Educational Resources Information Center

    Contreras, José

    2014-01-01

    This paper describes how the author's students (in-service and pre-service secondary mathematics teachers) enrolled in college geometry courses use the Geometers' Sketchpad (GSP) to gain insight to formulate, confirm, test, and refine conjectures to solve the classical airport problem for triangles. The students are then provided with strategic…

  1. Land Problems and People Problems - The Eskimo as Conservationist.

    ERIC Educational Resources Information Center

    Lotz, Jim

    Much research has been done about the Eskimos, but with little beneficial result to the Eskimo. Economic development of northern Canadian territories has resulted in a wider gap between Eskimos and other Canadians since benefits accrue only to the second group. Evidence of damage to the land is already appearing. To solve problems of land use,…

  2. Image processing: some challenging problems.

    PubMed Central

    Huang, T S; Aizawa, K

    1993-01-01

    Image processing can be broadly defined as the manipulation of signals which are inherently multidimensional. The most common such signals are photographs and video sequences. The goals of processing or manipulation can be (i) compression for storage or transmission; (ii) enhancement or restoration; (iii) analysis, recognition, and understanding; or (iv) visualization for human observers. The use of image processing techniques has become almost ubiquitous; they find applications in such diverse areas as astronomy, archaeology, medicine, video communication, and electronic games. Nonetheless, many important problems in image processing remain unsolved. It is the goal of this paper to discuss some of these challenging problems. In Section I, we mention a number of outstanding problems. Then, in the remainder of this paper, we concentrate on one of them: very-low-bit-rate video compression. This is chosen because it involves almost all aspects of image processing. PMID:8234312

  3. Interference problems for nongeostationary satellites

    NASA Technical Reports Server (NTRS)

    Sollfrey, W.

    1984-01-01

    The interference problems faced by nongeostationary satellites may be of major significance. A general discussion indicates the scope of the problems and describes several configurations of importance. Computer programs are described, which are employed by NASA/JPL and the U.S. Air Force Satellite Control Facility to provide interference-free scheduling of commands and data transmission. Satellite system mission planners are not concerned with the precise prediction of interference episodes, but rather with the expected total amount of interference, the mean and maximum duration of events, and the mean spacing between episodes. The procedures in the theory of probability developed by the author which permit calculation of such quantities are described and applied to several real cases. It may be anticipated that the problems will become steadily worse in the future as more and more data transmissions attempt to occupy the same frequency band.

  4. Psychological Distress and Problem Drinking.

    PubMed

    Mentzakis, Emmanouil; Roberts, Bayard; Suhrcke, Marc; McKee, Martin

    2016-03-01

    We examine the influence of harmful alcohol use on mental health using a flexible two-step instrumental variables approach and household survey data from nine countries of the former Soviet Union. Using alcohol advertisements to instrument for alcohol, we show that problem drinking has a large detrimental effect on psychological distress, with problem drinkers exhibiting a 42% increase in the number of mental health problems reported and a 15% higher chance of reporting very poor mental health. Ignoring endogeneity leads to an underestimation of the damaging effect of excessive drinking. Findings suggest that more effective alcohol policies and treatment services in the former Soviet Union may have added benefits in terms of reducing poor mental health.

  5. The Random Quadratic Assignment Problem

    NASA Astrophysics Data System (ADS)

    Paul, Gerald; Shao, Jia; Stanley, H. Eugene

    2011-11-01

    The quadratic assignment problem, QAP, is one of the most difficult of all combinatorial optimization problems. Here, we use an abbreviated application of the statistical mechanics replica method to study the asymptotic behavior of instances in which the entries of at least one of the two matrices that specify the problem are chosen from a random distribution P. Surprisingly, the QAP has not been studied before using the replica method despite the fact that the QAP was first proposed over 50 years ago and the replica method was developed over 30 years ago. We find simple forms for C min and C max , the costs of the minimal and maximum solutions respectively. Notable features of our results are the symmetry of the results for C min and C max and their dependence on P only through its mean and standard deviation, independent of the details of P.

  6. Theoretical Problems in Materials Science

    NASA Technical Reports Server (NTRS)

    Langer, J. S.; Glicksman, M. E.

    1985-01-01

    Interactions between theoretical physics and material sciences to identify problems of common interest in which some of the powerful theoretical approaches developed for other branches of physics may be applied to problems in materials science are presented. A unique structure was identified in rapidly quenched Al-14% Mn. The material has long-range directed bonds with icosahedral symmetry which does not form a regular structure but instead forms an amorphous-like quasiperiodic structure. Finite volume fractions of second phase material is advanced and is coupled with nucleation theory to describe the formation and structure of precipitating phases in alloys. Application of the theory of pattern formation to the problem of dendrite formation is studied.

  7. Deinstitutionalization in Greece: Ethical problems.

    PubMed

    Ploumpidis, D; Garanis-Papadatos, T; Economou, M

    2008-10-01

    The following paper is based on a Concerted Action which focused on the "Ethical aspects of deistinstutionalisation in mental health care" in 2001. It investigates the development and the ethical dilemmas posed by deinstitutionalization in Greece. This movement has recently undergone a very active phase but the transition from the traditional model of psychiatric care to the community based system unavoidably creates many ethical problems related to the professionals' attitude towards individual liberties, dignity and other fundamental rights of mentally ill persons. These problems exist not only in the level of the therapist-patient relationship but in the level of policy making as well as its implementation. Moreover, the paper deals with specific ethical problems such as stigmatisation and isolation in the community context, as well as the role of the family.

  8. Challenge problems for artificial intelligence

    SciTech Connect

    Selman, B.; Brooks, R.A.; Dean, T.

    1996-12-31

    AI textbooks and papers of ten discuss the big questions, such as {open_quotes}how to reason with uncertainty{close_quotes}, {open_quotes}how to reason efficiently{close_quotes}, or {open_quotes}how to improve performance through learning.{close_quotes} It is more difficult, however, to find descriptions of concrete problems or challenges that are still ambitious and interesting, yet not so open-ended. The goal of this panel is to formulate a set of such challenge problems for the field. Each panelist was asked to formulate one or more challenges. The emphasis is on problems for which there is a good chance that they will be resolved within the next five to ten years.

  9. Image Processing: Some Challenging Problems

    NASA Astrophysics Data System (ADS)

    Huang, T. S.; Aizawa, K.

    1993-11-01

    Image processing can be broadly defined as the manipulation of signals which are inherently multidimensional. The most common such signals are photographs and video sequences. The goals of processing or manipulation can be (i) compression for storage or transmission; (ii) enhancement or restoration; (iii) analysis, recognition, and understanding; or (iv) visualization for human observers. The use of image processing techniques has become almost ubiquitous; they find applications in such diverse areas as astronomy, archaeology, medicine, video communication, and electronic games. Nonetheless, many important problems in image processing remain unsolved. It is the goal of this paper to discuss some of these challenging problems. In Section I, we mention a number of outstanding problems. Then, in the remainder of this paper, we concentrate on one of them: very-low-bit-rate video compression. This is chosen because it involves almost all aspects of image processing.

  10. Food production -- problems and prospects.

    PubMed

    Anifowoshe, T O

    1990-03-01

    Improvements are needed in balancing the problems associated with population growth and food production. A review of the problems of rapid population growth and declining food production and suggestions for resolution are given. World population has increased over the past 10 years by 760 million, which is equal to adding the combined population of Africa and South America. Future increases are expected to bring total population to 6.1 billion by the year 2000 and 8.2 billion in 2025 (exponential increases). Food production/capita has declined since 1971 in the world and in Nigeria, particularly in the recent past. The food production problem is technical, environmental, social, political, and economic. Various scientific and technological methods for increasing food production are identified: mechanization, irrigation, use of fertilizers, control of weeds and insects, new varieties of farm animals or high-yielding strains of grain, land reclamation, soil conservation, river basin development, adequate storage facilities, infrastructure development, and birth control. Economic and social approaches involve short-term and long-term strategies in social readjustment and institutional change. For instance, large scale farmers should become contract growers for certain firms. Bureaucratic red tape should be eliminated in institutions which provide agricultural services. Environmental problems need urgent attention. Some of these problems are soil erosion from mechanization, water salinization from irrigation, accumulation of DDT in food and water and animal life from pesticide use, and water pollution from chemical fertilizers. Food production can be increased with more ecologically sound practices. Information about weather and weather forecasting allows for more suitable land management. The influence of rainfall (the amount and distribution) in Nigeria is greater than any other climatic factor. Solar radiation is a significant feature in production of dry matter and

  11. Problems and promises of NODC

    NASA Astrophysics Data System (ADS)

    Richman, Barbara T.

    The National Oceanographic Data Center (NODC), the nation's warehouse for ocean data, often hears complaints from its users that requests for data from recent oceanographic cruises cannot be filled. The complaint highlights both sides of the data traffic problem that besets NODC: Researchers delay sending their data to the center, and NODC has had difficulties in processing some data, especially when changes in the computer systems are made or when data is submitted in incomplete form. Plans within NODC promise to minimize the data processing problems with eventual direct communication from desktop to data base.

  12. Statistical inference for inverse problems

    NASA Astrophysics Data System (ADS)

    Bissantz, Nicolai; Holzmann, Hajo

    2008-06-01

    In this paper we study statistical inference for certain inverse problems. We go beyond mere estimation purposes and review and develop the construction of confidence intervals and confidence bands in some inverse problems, including deconvolution and the backward heat equation. Further, we discuss the construction of certain hypothesis tests, in particular concerning the number of local maxima of the unknown function. The methods are illustrated in a case study, where we analyze the distribution of heliocentric escape velocities of galaxies in the Centaurus galaxy cluster, and provide statistical evidence for its bimodality.

  13. Skin Problems After Ostomy Surgery

    PubMed Central

    Dietz, Katharina

    1978-01-01

    For many years people with colostomies, ileostomies and urinary diversions have had to live in a shadow due to ill-fitting appliances. This has lead to odor problems, skin excoriation, depression, and even withdrawal from society. Dr. Rupert Turnbull from the Cleveland Clinic in Ohio saw the need for an enterostomal therapy service some ten years ago. Patients rehabilitated in self-care by an enterostomal therapist, pre and post-operatively, now rarely have any skin problems. During the last ten years new and better appliances have been developed, and with a well constructed stoma in a suitable site, any ostomate can return to a normal life. PMID:21301501

  14. [Psychological problems of thalassemic subjects].

    PubMed

    Guasco, G; La Mantia, A; Cuniolo, A

    1987-01-01

    Analysis of psychological problems of the thalassemic subject shown with these following tests: Der Baumtest, drawing of the human figure. Moreover, we made meetings with all boys and their parents during their stay in the day-hospital. These tests have shown subjective conflicts (fear and uncertainty of future due to illness felt as aggression and fault, depressive moods and loneliness, problems of communication, hope in a magic recovery opposite to the constant discomfort of the therapeutic dependence) and relational conflicts (ambivalence towards parents, difficulties in becoming a part of the social and school environment).

  15. Euler's three-body problem

    NASA Astrophysics Data System (ADS)

    Wild, Walter J.

    1980-04-01

    The simplest three-body problem that attracts physical interest is the one first studied by Euler. In Euler's problem, a primary and secondary mass are fixed in space, a given distance apart, and a test mass is allowed to move unrestricted in their superimposed gravitational fields. The equations of motion are derived and solved via a simple numerical procedure. The algorithm is adaptable to a small programmable calculator and should help to stimulate interest in the classroom. Several examples of motion are discussed and graphically presented.

  16. Ten Problems in Artificial Intelligence.

    DTIC Science & Technology

    1987-01-01

    REPORT NUMBER -9 dVT ACCES~iIVN NO𔃻 3 RCCIPIENT’S CATALOG NUMGER 4. TITLE (and Subtile) S YEOF REPORT A PERIOO COvEREC Ten ~ .i in Arti’Ficiz1...7 AD-F1183 552 TEN PROBLEMS IN RTIFICIL INTELLIGENCE(U) VLE UNIV j’ N UN HVEN CT DEPT OF COMPUTER SCIENCE RSCHANK ET AL. JAN 8? VALEU/CSD/RR-514...IET VI Ten Problems in Artificial Intelligence Roger C. Schank Christopher C. Owens YALEU/CSD/RR #514 January 1987 I~~~. -- ’ -.... e"- . .I YALE

  17. Energy Problems Provide Job Opportunities.

    ERIC Educational Resources Information Center

    Moore, Allen B.

    In response to the problems created by a diminishing energy supply but an increasing energy demand, this second in a series of national reports studies the linkage of vocational education and energy. Through an examination of selected literature with reference to types of energy resources, the author identifies the emerging occupations related to…

  18. Teaching through Collaborative Problem Solving.

    ERIC Educational Resources Information Center

    Blandford, A. E.

    1994-01-01

    Discussion of a prototype intelligent education system called WOMBAT (Weighted Objectives Method by Arguing with the Tutor) focuses on dialogue and negotiation in collaborative problem solving. The results of a formative evaluation, in which the system was used by 10 subjects who commented on various aspects of the design, are presented. (Contains…

  19. Investigating the Antibiotic Resistance Problem.

    ERIC Educational Resources Information Center

    Lawson, Michael; Lawson, Amy L.

    1998-01-01

    Seeks to give teachers useful information on the extent of the problem of antibiotic-resistant bacteria, mechanisms bacteria use to resist antibiotics, the causes of the emergence of antibiotic-resistant organisms, and practices that can prevent or reverse this trend. Contains 19 references. (DDR)

  20. Problem Gambling on College Campuses

    ERIC Educational Resources Information Center

    McComb, Jennifer L.; Hanson, William E.

    2009-01-01

    The vast majority of college students gamble, with some doing so problematically. This article discusses gambling and problem gambling among college students, framing it as an emerging health issue on college campuses nationwide. Given that 4 out of 5 college students admit to gambling, and that approximately 8% gamble problematically, it is…

  1. Modeling Applied to Problem Solving

    NASA Astrophysics Data System (ADS)

    Pawl, Andrew; Barrantes, Analia; Pritchard, David E.

    2009-11-01

    We describe a modeling approach to help students learn expert problem solving. Models are used to present and hierarchically organize the syllabus content and apply it to problem solving, but students do not develop and validate their own Models through guided discovery. Instead, students classify problems under the appropriate instructor-generated Model by selecting a system to consider and describing the interactions that are relevant to that system. We believe that this explicit System, Interactions and Model (S.I.M.) problem modeling strategy represents a key simplification and clarification of the widely disseminated modeling approach originated by Hestenes and collaborators. Our narrower focus allows modeling physics to be integrated into (as opposed to replacing) a typical introductory college mechanics course, while preserving the emphasis on understanding systems and interactions that is the essence of modeling. We have employed the approach in a three-week review course for MIT freshmen who received a D in the fall mechanics course with very encouraging results.

  2. Psychological Problems in Mental Deficiency.

    ERIC Educational Resources Information Center

    Sarason, Seymour B.; Doris, John

    A statement of goals and the rationale for organization precede a historical discussion of mental deficiency and society. The problem of labels like IQ and brain injured and the consequences of the diagnostic process are illustrated by case histories; case studies are also used to examine the criteria used to decide who is retarded and to discuss…

  3. "Top School Problems" Are Myths.

    ERIC Educational Resources Information Center

    Males, Mike

    1992-01-01

    A well-known "study" comparing the top school problems of 1940 (talking and gum chewing) with those of 1987 (drug abuse, pregnancy, and violence) is nonexistent. In 1940, 49 percent of all youth did not finish high school, 37,000 teenagers died from violence or disease, and 335,000 teens gave birth. Educators should discount pastoral…

  4. The Scientist as Problem Solver.

    DTIC Science & Technology

    1989-01-01

    history. or imagined history. no magic and no mystery Each step appears to proceed. if not inexorably at least plausibly from the preceding one If the...discovery process appears quite unremarkable. The problem was found in the literatue (Goodwin S paper). and it can be represented in a quite standard way by

  5. Robot, computer problem solving system

    NASA Technical Reports Server (NTRS)

    Becker, J. D.; Merriam, E. W.

    1973-01-01

    The TENEX computer system, the ARPA network, and computer language design technology was applied to support the complex system programs. By combining the pragmatic and theoretical aspects of robot development, an approach is created which is grounded in realism, but which also has at its disposal the power that comes from looking at complex problems from an abstract analytical point of view.

  6. The Problem with Toxic Wastes.

    ERIC Educational Resources Information Center

    Beecher, John L.; Fossa, Arthur J.

    1980-01-01

    Traced is the historical development of toxic waste problems in western New York State from 1825 to the present. Three major data sources are described: Industrial Chemical Survey, Inventory of Industrial Waste Generation Study, and the Interagency Task Force Study, developed by the Department of Environmental Conservation to prevent future…

  7. Selected Problems in Sports Safety.

    ERIC Educational Resources Information Center

    American Alliance for Health, Physical Education, and Recreation, Washington, DC.

    This publication, covering a broad spectrum of sports safety problems, is designed as a source of information for those who plan, organize, administer, or evaluate various physical education and recreational activities, athletics, or sports. In the first section, the prevention of sports injury is stressed with attention to different age groups…

  8. Robot computer problem solving system

    NASA Technical Reports Server (NTRS)

    Becker, J. D.; Merriam, E. W.

    1974-01-01

    The conceptual, experimental, and practical aspects of the development of a robot computer problem solving system were investigated. The distinctive characteristics were formulated of the approach taken in relation to various studies of cognition and robotics. Vehicle and eye control systems were structured, and the information to be generated by the visual system is defined.

  9. Adopting Children with Attachment Problems.

    ERIC Educational Resources Information Center

    Hughes, Daniel A.

    1999-01-01

    Notes that attachment behavior in infants is a facet of normal child development, and that children with attachment problems require special attention during and after the adoption process. Presents actions needed to increase the probability that such children can be successfully adopted, detailed attachment patterns, and parenting strategies and…

  10. University Presses: Problems and Prospects.

    ERIC Educational Resources Information Center

    Meeker, Robert B.

    Historical information on university presses and their problems are considered. University presses in the United States have their roots in 15th century England when the Oxford University Press was established in 1478. The first U.S. press to use the term "university press" was Cornell University; the press operated from 1869 until it…

  11. Human Problem Solving in 2008

    ERIC Educational Resources Information Center

    Pizlo, Zygmunt

    2008-01-01

    This paper presents a bibliography of more than 200 references related to human problem solving, arranged by subject matter. The references were taken from PsycInfo database. Journal papers, book chapters, books and dissertations are included. The topics include human development, education, neuroscience, research in applied settings, as well as…

  12. Introduction: Unsolved Problems on Noise

    NASA Astrophysics Data System (ADS)

    Oriols, X.; Ciliberto, S.

    2016-05-01

    This paper is an introduction to the special issue of the 7th Int. Conf. on Unsolved Problems on Noise (UPoN) that took place at Casa Convalescència in Barcelona (Spain) in July 2015. The aim of the UPoN conferences is to provide a forum for researchers working on different fields of noise, fluctuations and variability, where they present their scientific problems which resist solutions. The papers of this Special Issue reflect the interdisciplinary topics (physics, biology, circuits, financial markets, psychology, technology, etc) presented at the UPoN conference. Noise is not only a hindrance to signal detection, but it is indeed a valuable source of information (not present in the signal) that help us to get a deeper understanding on how Nature works. This special issue of the 7th International Conference on Unsolved Problems on Noise (UPoN) is dedicated to Laszlo Kish in the occasion of his 60th birthday. He organized the first edition of these UPoN conferences in Szeged (Hungary) in 1996. Many of us have greatly benefited from his ‘volcanic imagination in tackling new problems from unconventional points of views’.

  13. Building Collections. The Problem Novel

    ERIC Educational Resources Information Center

    Krapp, JoAnn Vergona

    2005-01-01

    Realistic fiction has changed dramatically over the years. Formerly a sentimental, family-oriented story, today's realism focuses on today's problems and the protagonist's struggle to overcome them. Parents, once portrayed as protectors of the children, now often are cast as failures, needing help themselves. Yesterday's taboo subjects--drugs,…

  14. Dyslexia: Problems of Reading Disabilities.

    ERIC Educational Resources Information Center

    Goldberg, Herman K.; Schiffman, Gilbert B.

    The purpose of this book is to provide an understanding of both the educational and medical aspects of reading and to show how they are interrelated in reading disabilities. The various aspects of reading disabilities are presented in the following chapters: Introduction to the Reading Problem; Early Predictive Studies; Psychological Evaluation;…

  15. Error Patterns in Problem Solving.

    ERIC Educational Resources Information Center

    Babbitt, Beatrice C.

    Although many common problem-solving errors within the realm of school mathematics have been previously identified, a compilation of such errors is not readily available within learning disabilities textbooks, mathematics education texts, or teacher's manuals for school mathematics texts. Using data on error frequencies drawn from both the Fourth…

  16. Solving the wrong hierarchy problem

    DOE PAGES

    Blinov, Nikita; Hook, Anson

    2016-06-29

    Many theories require augmenting the Standard Model with additional scalar fields with large order one couplings. We present a new solution to the hierarchy problem for these scalar fields. We explore parity- and Z2-symmetric theories where the Standard Model Higgs potential has two vacua. The parity or Z2 copy of the Higgs lives in the minimum far from the origin while our Higgs occupies the minimum near the origin of the potential. This approach results in a theory with multiple light scalar fields but with only a single hierarchy problem, since the bare mass is tied to the Higgs massmore » by a discrete symmetry. The new scalar does not have a new hierarchy problem associated with it because its expectation value and mass are generated by dimensional transmutation of the scalar quartic coupling. The location of the second Higgs minimum is not a free parameter, but is rather a function of the matter content of the theory. As a result, these theories are extremely predictive. We develop this idea in the context of a solution to the strong CP problem. Lastly, we show this mechanism postdicts the top Yukawa to be within 1σ of the currently measured value and predicts scalar color octets with masses in the range 9-200 TeV.« less

  17. Gender and Mathematical Problem Solving.

    ERIC Educational Resources Information Center

    Duffy, Jim; Gunther, Georg; Walters, Lloyd

    1997-01-01

    Studied the relationship between gender and mathematical problem solving in 83 male and 76 female high achieving Canadian 12-year-olds. Gender differences were found on the Canadian Test of Basic Skills but not on the GAUSS assessment. Implications for the discussion of the origin of gender differences in mathematics are discussed. (SLD)

  18. Family Problems and Youth Unemployment.

    ERIC Educational Resources Information Center

    de Goede, Martijn; Spruijt, Ed; Maas, Cora; Duindam, Vincent

    2000-01-01

    Examines how family and personal characteristics relate to the employment situation of adolescents (N=995) in Denmark. Results show that parental divorce, parental unemployment (only for males), low parental affective involvement, and adolescent relationship problems were related to youth unemployment, but educational career and work commitment…

  19. Rosetta Stones for Energy Problems.

    ERIC Educational Resources Information Center

    Hayden, Howard C.

    1981-01-01

    Demonstrates, using specific problems, how various energy units can be converted to joules and power units to watts. Conversion tables are provided for power, energy, generation values, thermal insulation, consumption values, sunlight, with tables also on metric prefixes and time conversions. (SK)

  20. The Legal Audit: Preventing Problems.

    ERIC Educational Resources Information Center

    Perlman, Daniel H.

    1987-01-01

    Suffolk University initiated two audits that proved beneficial: a legal audit and an insurance audit. A legal audit involves having an attorney review a college's contracts, personnel handbooks, catalogs, etc., in order to anticipate and prevent problems. An insurance audit reviews an institution's risk coverage. (MLW)

  1. Breathing Problems: An Individualized Program.

    ERIC Educational Resources Information Center

    Vodola, Thomas M.

    As one of the components of the Project ACTIVE (All Children Totally Involved Exercising) Teacher Training Model Kit, the manual is designed to enable the educator to organize, conduct, and evaluate individualized-personalized physical education programs for children (prekindergarten through high school) with breathing problems. An introductory…

  2. The Child-Fat Problem.

    ERIC Educational Resources Information Center

    Eberstadt, Mary

    2003-01-01

    Experts believe that child obesity is a serious medical problem that affects people in all socioeconomic groups. Suggests that there is a relationship between absentee parents, particularly mothers, and obese children, focusing on working/absentee mothers, television watching habits, the prophylactic effect of breastfeeding, and poor exercise…

  3. Human Problem Solving in 2006

    ERIC Educational Resources Information Center

    Pizlo, Zygmunt

    2007-01-01

    This paper presents a bibliography of a little more than 100 references related to human problem solving, arranged by subject matter. The references were taken from PsycInfo and Compendex databases. Only journal papers, books and dissertations are included. The topics include human development, education, neuroscience, research in applied…

  4. Childhood Obesity: A Heavy Problem

    ERIC Educational Resources Information Center

    Costley, Kevin C.; Leggett, Timothy

    2010-01-01

    The youth of today are faced with a big problem; they are becoming more obese every day. The time of children playing outside all day and being extremely active has been overtaken by the television and video games. The days of sitting down as a family and eating a good healthy meal has been replaced by the rush to the nearest fast food…

  5. Solving the wrong hierarchy problem

    SciTech Connect

    Blinov, Nikita; Hook, Anson

    2016-06-29

    Many theories require augmenting the Standard Model with additional scalar fields with large order one couplings. We present a new solution to the hierarchy problem for these scalar fields. We explore parity- and Z2-symmetric theories where the Standard Model Higgs potential has two vacua. The parity or Z2 copy of the Higgs lives in the minimum far from the origin while our Higgs occupies the minimum near the origin of the potential. This approach results in a theory with multiple light scalar fields but with only a single hierarchy problem, since the bare mass is tied to the Higgs mass by a discrete symmetry. The new scalar does not have a new hierarchy problem associated with it because its expectation value and mass are generated by dimensional transmutation of the scalar quartic coupling. The location of the second Higgs minimum is not a free parameter, but is rather a function of the matter content of the theory. As a result, these theories are extremely predictive. We develop this idea in the context of a solution to the strong CP problem. Lastly, we show this mechanism postdicts the top Yukawa to be within 1σ of the currently measured value and predicts scalar color octets with masses in the range 9-200 TeV.

  6. Causality in Solving Economic Problems

    ERIC Educational Resources Information Center

    Robinson, A. Emanuel; Sloman, Steven A.; Hagmayer, York; Hertzog, Christopher K.

    2010-01-01

    The role of causal beliefs in people's decisions when faced with economic problems was investigated. Two experiments are reported that vary the causal structure in prisoner's dilemma-like economic situations. We measured willingness to cooperate or defect and collected justifications and think-aloud protocols to examine the strategies that people…

  7. Customer Service & Team Problem Solving.

    ERIC Educational Resources Information Center

    Martin, Sabrina Budasi

    This curriculum guide provides materials for a six-session, site-specific training course in customer service and team problem solving for the Claretian Medical Center. The course outline is followed the six lesson plans. Components of each lesson plan include a list of objectives, an outline of activities and discussion topics for the lesson,…

  8. Decision Making and Environmental Problems

    ERIC Educational Resources Information Center

    Thompson, Bertha Boya

    1977-01-01

    Suggests a decision-making model that can be applied by high school students to a variety of environmental problems, and illustrates how the model can be used to make decisions concerning future energy shortages. Provides criteria for judging allocation priorities of limited resources and stimulates awareness of alternative solutions to energy…

  9. Literacy as a Human Problem.

    ERIC Educational Resources Information Center

    Raymond, James C., Ed.

    First presented as papers in a symposium on literacy conducted at the University of Alabama, essays in this volume explore three areas of human literacy--law, linguistics, and the English language; testing; and literacy's relation with culture and human consciousness. Following an introduction examining literacy as a human problem, the following…

  10. Robot computer problem solving system

    NASA Technical Reports Server (NTRS)

    Becker, J. D.; Merriam, E. W.

    1974-01-01

    The conceptual, experimental, and practical phases of developing a robot computer problem solving system are outlined. Robot intelligence, conversion of the programming language SAIL to run under the THNEX monitor, and the use of the network to run several cooperating jobs at different sites are discussed.

  11. English as a Problem Language

    ERIC Educational Resources Information Center

    Moss, Peter

    2010-01-01

    At a time when English has emerged as the dominant language of academic communication, there is a disturbing silence about the risks and problems attendant on this development and a failure to ask critical questions about its consequences. Who gains and who loses? What is lost in translation? What are the consequences of one way linguistic…

  12. Problems of Adjustment to School.

    ERIC Educational Resources Information Center

    Bartolini, Leandro A.

    This paper, one of several written for a comprehensive policy study of early childhood education in Illinois, examines and summarizes the literature on the problems of young children in adjusting to starting school full-time and describes the nature and extent of their difficulties in relation to statewide educational policy. The review of studies…

  13. The Problem of World Hunger.

    ERIC Educational Resources Information Center

    Czarra, Fred R.; Long, Cathryn J., Eds.

    1983-01-01

    The major hunger problem today is chronic undernutrition, the primary cause of which is poverty. Hunger can be alleviated through food supplements, nutrition programs, and disaster relief. It can be eliminated by redistributing existing wealth and producing enough food and through equitable economic growth and a world food security system. (CS)

  14. Energy: A Growing National Problem?

    ERIC Educational Resources Information Center

    National Wildlife Federation, Washington, DC.

    This publication highlights information about the energy problem and indicates some possible solutions. Americans must find new energy sources and more efficient ways to utilize existing energy supplies. The National Wildlife Federation urges conservation of existing fuel supplies, exploration of new potential energy sources, adaption of some…

  15. Urban Problems and Community Development.

    ERIC Educational Resources Information Center

    Ferguson, Ronald F., Ed.; Dickens, William T., Ed.

    The essays in this collection promote a conception of community development that entails building practical capacities to improve the quality of life among residents of targeted neighborhoods. The causes, consequences, and potential solutions of urban problems that lie both inside and outside neighborhood borders are emphasized. The chapters are:…

  16. Problem Solvers' Conceptions about Osmosis.

    ERIC Educational Resources Information Center

    Zuckerman, June T.

    1994-01-01

    Discusses the scheme and findings of a study designed to identify the conceptual knowledge used by high school students to solve a significant problem related to osmosis. Useful tips are provided to teachers to aid students in developing constructs that maximize understanding. (ZWH)

  17. Sour landfill gas problem solved

    SciTech Connect

    Nagl, G.; Cantrall, R.

    1996-05-01

    In Broward County, Fla., near Pompano Beach, Waste Management of North America (WMNA, a subsidiary of WMX Technologies, Oak Brook, IL) operates the Central Sanitary Landfill and Recycling Center, which includes the country`s largest landfill gas-to-energy plant. The landfill consists of three collection sites: one site is closed, one is currently receiving garbage, and one will open in the future. Approximately 9 million standard cubic feet (scf) per day of landfill gas is collected from approximately 300 wells spread over the 250-acre landfill. With a dramatic increase of sulfur-containing waste coming to a South Florida landfill following Hurricane Andrew, odors related to hydrogen sulfide became a serious problem. However, in a matter of weeks, an innovative desulfurization unit helped calm the landfill operator`s fears. These very high H{sub 2}S concentrations caused severe odor problems in the surrounding residential area, corrosion problems in the compressors, and sulfur dioxide (SO{sub 2}) emission problems in the exhaust gas from the turbine generators.

  18. Special Problems of the Elderly.

    ERIC Educational Resources Information Center

    Hull, Kathleen V.

    Within the next 40 years, people age 65 and over will comprise 20% of the population, yet problems facing this older generation and their families are just coming to the attention of researchers and the public. Accordingly, this literature review focuses on the special needs of older adults and their families. After an introductory overview, the…

  19. Problems in unification and supergravity

    SciTech Connect

    Farrar, G.; Henyey, F.

    1984-01-01

    Problems in unification of the various gauge groups, quantum gravity, supersymmetry and supergravity, compact dimensions of space-time, and conditions at the beginning of the universe are discussed. Separate entries were prepared for the data base for the 15 papers presented. (WHK)

  20. The Particle--Motion Problem.

    ERIC Educational Resources Information Center

    Demana, Franklin; Waits, Bert K.

    1993-01-01

    Discusses solutions to real-world linear particle-motion problems using graphing calculators to simulate the motion and traditional analytic methods of calculus. Applications include (1) changing circular or curvilinear motion into linear motion and (2) linear particle accelerators in physics. (MDH)

  1. The Zero Exemplar Distance Problem

    NASA Astrophysics Data System (ADS)

    Jiang, Minghui

    Given two genomes with duplicate genes, Zero Exemplar Distance is the problem of deciding whether the two genomes can be reduced to the same genome without duplicate genes by deleting all but one copy of each gene in each genome. Blin, Fertin, Sikora, and Vialette recently proved that Zero Exemplar Distance for monochromosomal genomes is NP-hard even if each gene appears at most two times in each genome, thereby settling an important open question on genome rearrangement in the exemplar model. In this paper, we give a very simple alternative proof of this result. We also study the problem Zero Exemplar Distance for multichromosomal genomes without gene order: from one direction, we show that this problem is NP-hard even if each gene appears at most two times in each genome; from the other direction, we show that this problem admits a polynomial-time algorithm if only one of the two genomes has duplicate genes, and is fixed-parameter tractable if the parameter is the maximum number of chromosomes in each genome.

  2. Human Problem Solving in 2012

    ERIC Educational Resources Information Center

    Funke, Joachim

    2013-01-01

    This paper presents a bibliography of 263 references related to human problem solving, arranged by subject matter. The references were taken from PsycInfo and Academic Premier data-base. Journal papers, book chapters, and dissertations are included. The topics include human development, education, neuroscience, and research in applied settings. It…

  3. Teachers' Perceptions and "Problem" Pupils

    ERIC Educational Resources Information Center

    Leach, David

    1977-01-01

    Discusses the interaction between children's behavior, and the way in which teachers perceive them. Considers the extent to which there is a relationship between the individual teacher's view of children, his response to difficult children, and the number and nature of children reported to present problems. (Editor/RK)

  4. Linearization problem in pseudolite surveys

    NASA Astrophysics Data System (ADS)

    Cellmer, Slawomir; Rapinski, Jacek

    2010-06-01

    GPS augmented with pseudolites (PL), can be used in various engineering surveys. Also pseudolite—only navigation system can be designed and used in any place, even if GPS signal is not available (Kee et al. Development of indoor navigation system using asynchronous pseudolites, 1038-1045, 2000). Especially in engineering surveys, where harsh survey environment is common, pseudolites have a lot of applications. Pseudolites may be used in construction sites, open pit mines, city canyons, GPS and PL baseline processing is similar, although there are few differences that must be taken into account. One of the major issues is linearization problem. The source of the problem is neglecting second terms of Taylor series expansion in GPS baseline processing software. This problem occurs when the pseudolite is relatively close to the receiver, which is the case in PL surveys. In this paper authors presents the algorithm for GPS + PL data processing including, neglected in classical GPS only approach, second terms of Taylor series expansion. The mathematical model of adjustment problem, detailed proposal of application in baseline processing algorithms, and numerical tests are presented.

  5. Information Problems and the Law

    ERIC Educational Resources Information Center

    Jacob, R.

    1972-01-01

    The first part of the paper deals with statute law and describes the inadequacy of the official Statutes Revised' system for maintaining up-to-date records. There is a similar lack of official retrieval tools for tracing information on case law. The problems of factual information retrieval are dealt with briefly. (Author/NH)

  6. An Overview of Educational Problems.

    ERIC Educational Resources Information Center

    Lipson, Joseph

    As part of the activities establishing the National Institute of Education, a Planning Unit evolved to obtain advice from experts on what the objectives, activities, and organizational structures of the new organization should be. This overview, part of the Planning Unit studies, lists and analyzes educational problems. An introduction presents a…

  7. Language Problems of Developing Nations.

    ERIC Educational Resources Information Center

    Fishman, Joshua A., Ed.; And Others

    Most of the papers in this collection were presented at a conference on language problems of the developing nations at Airlie House, Warrenton, Virginia in November 1966. This conference was one of the several organized and sponsored by the Committee on Sociolinguistics of the Social Science Research Council in its effort to promote…

  8. Time Out for Problem Solving.

    ERIC Educational Resources Information Center

    Champagne, Audrey B.; And Others

    Teachers in elementary schools, supervisors of instruction, and other educational practitioners are the primary audience for this publication. The paper presents philosophical, psychological, and practical reasons for including a problem-solving approach in elementary school instruction. It draws on the writings of John Dewey, Jean Piaget, James…

  9. Solving the wrong hierarchy problem

    NASA Astrophysics Data System (ADS)

    Blinov, Nikita; Hook, Anson

    2016-06-01

    Many theories require augmenting the Standard Model with additional scalar fields with large order one couplings. We present a new solution to the hierarchy problem for these scalar fields. We explore parity- and Z_2 -symmetric theories where the Standard Model Higgs potential has two vacua. The parity or Z_2 copy of the Higgs lives in the minimum far from the origin while our Higgs occupies the minimum near the origin of the potential. This approach results in a theory with multiple light scalar fields but with only a single hierarchy problem, since the bare mass is tied to the Higgs mass by a discrete symmetry. The new scalar does not have a new hierarchy problem associated with it because its expectation value and mass are generated by dimensional transmutation of the scalar quartic coupling. The location of the second Higgs minimum is not a free parameter, but is rather a function of the matter content of the theory. As a result, these theories are extremely predictive. We develop this idea in the context of a solution to the strong CP problem. We show this mechanism postdicts the top Yukawa to be within 1 σ of the currently measured value and predicts scalar color octets with masses in the range 9-200 TeV.

  10. Testing Under Fire: Chicago's Problem.

    ERIC Educational Resources Information Center

    Byrd, Manford, Jr.

    The history and development of city-wide testing programs in Chicago since 1936 are reviewed and placed in context with the impact on testing of Sputnik and the passage of the National Defense Education Act of 1958. Current testing problems include the time lag between events and curricular changes and new test construction, the time lag between…

  11. Common Sleep Problems (For Teens)

    MedlinePlus

    ... with a sleep deficit are unable to concentrate, study, and work effectively. They can also have emotional problems, like ... p.m. to reach the 9-hour mark. Studies have found that many teens have trouble ... their brains naturally work on later schedules and aren't ready for ...

  12. Predicting the Problem Behavior in Adolescents

    ERIC Educational Resources Information Center

    Karaman, Neslihan G.

    2013-01-01

    Problem statement: Problem behavior theory describes both protective factors and risk factors to explain adolescent problem behaviors, such as delinquency, alcohol use, and reckless driving. The theory holds that problem behaviors involving risky behavior are used by adolescents as a means to gain peer acceptance and respect. Problem behaviors…

  13. Problems on Divisibility of Binomial Coefficients

    ERIC Educational Resources Information Center

    Osler, Thomas J.; Smoak, James

    2004-01-01

    Twelve unusual problems involving divisibility of the binomial coefficients are represented in this article. The problems are listed in "The Problems" section. All twelve problems have short solutions which are listed in "The Solutions" section. These problems could be assigned to students in any course in which the binomial theorem and Pascal's…

  14. Formal language constrained path problems

    SciTech Connect

    Barrett, C.; Jacob, R.; Marathe, M.

    1997-07-08

    In many path finding problems arising in practice, certain patterns of edge/vertex labels in the labeled graph being traversed are allowed/preferred, while others are disallowed. Motivated by such applications as intermodal transportation planning, the authors investigate the complexity of finding feasible paths in a labeled network, where the mode choice for each traveler is specified by a formal language. The main contributions of this paper include the following: (1) the authors show that the problem of finding a shortest path between a source and destination for a traveler whose mode choice is specified as a context free language is solvable efficiently in polynomial time, when the mode choice is specified as a regular language they provide algorithms with improved space and time bounds; (2) in contrast, they show that the problem of finding simple paths between a source and a given destination is NP-hard, even when restricted to very simple regular expressions and/or very simple graphs; (3) for the class of treewidth bounded graphs, they show that (i) the problem of finding a regular language constrained simple path between source and a destination is solvable in polynomial time and (ii) the extension to finding context free language constrained simple paths is NP-complete. Several extensions of these results are presented in the context of finding shortest paths with additional constraints. These results significantly extend the results in [MW95]. As a corollary of the results, they obtain a polynomial time algorithm for the BEST k-SIMILAR PATH problem studied in [SJB97]. The previous best algorithm was given by [SJB97] and takes exponential time in the worst case.

  15. STEM education and Fermi problems

    NASA Astrophysics Data System (ADS)

    Holubova, Renata

    2017-01-01

    One of the research areas of Physics education is the study of the educational process. Investigations in this area are aimed for example on the teaching and learning process and its results. The conception of STEM education (Science, Technology, Engineering, and Mathematics) is discussed - it is one possible approach to the preparation of the curriculum and the focus on the educational process at basic and secondary schools. At schools in the Czech Republic STEM is much more realized by the application of interdisciplinary relations between subjects Physics-Nature-Technique. In both conceptions the aim is to support pupils' creativity, critical thinking, cross-curricular links. In this context the possibility of using Fermi problems in teaching Physics was discussed (as an interdisciplinary and constructivist activity). The aim of our research was the analysis of Fermi problems solving strategies, the ability of pupils to solve Fermi problems. The outcome of our analysis was to find out methods and teaching strategies which are important to use in teaching - how to solve qualitative and interdisciplinary tasks in physics. In this paper the theoretical basis of STEM education and Fermi problems will be presented. The outcome of our findings based on the research activities will be discussed so as our experiences from 10 years of Fermi problems competition that takes place at the Science Faculty, Palacky University in Olomouc. Changes in competencies of solving tasks by our students (from the point of view in terms of modern, activating teaching methods recommended by theory of Physics education and other science subjects) will be identified.

  16. Infertility as a psychological problem.

    PubMed

    Podolska, Magdalena Z; Bidzan, Mariola

    2011-01-01

    Recently there has been enormous progress in couple infertility treatment and diagnostics. Some couples cannot conceive despite the fact that there seems to be no objective somatic or immunologic reasons. In such situations gynaecologists are helpless and couples may be overwhelmed by a sense of defeat and hopelessness. Thus, consulting a psychologist or therapist on how to cope better with the problem may be a good solution. The objective of the following paper is to discuss the dilemmas of couples undergoing infertility treatment, related psychological problems, and to determine the need for psychological and therapeutic support. The study demonstrates numerous infertility causes and concludes that there is no universal method of dealing with them. Very frequently psychological and somatic problems overlap. Psychological causes are often the primary factors, but sometimes they are secondary derivatives of the therapeutic process. A wide scope of factors must be considered to attempt psychological analysis of patients treated for infertility including the influence of the family and relations within, reaction to the diagnosis and suggested treatment, the influence of religion on the treatment, the evaluation of the relations in the family of procreation, sexual life assessment, the sense of a woman's self-esteem and self-acceptance. Basing on empirical analysis it was concluded that all women treated for infertility want to create a full family. They have problems in coping with emotional liability during treatment and a sense of fear and failure. Understanding the psychological mechanisms observed in patients treated for infertility might help to diagnose the causes of their problems with facing the new, extremely difficult situation.

  17. Problem solving using soft systems methodology.

    PubMed

    Land, L

    This article outlines a method of problem solving which considers holistic solutions to complex problems. Soft systems methodology allows people involved in the problem situation to have control over the decision-making process.

  18. Retrofitting and the mu Problem

    SciTech Connect

    Green, Daniel; Weigand, Timo; /SLAC /Stanford U., Phys. Dept.

    2010-08-26

    One of the challenges of supersymmetry (SUSY) breaking and mediation is generating a {mu} term consistent with the requirements of electro-weak symmetry breaking. The most common approach to the problem is to generate the {mu} term through a SUSY breaking F-term. Often these models produce unacceptably large B{mu} terms as a result. We will present an alternate approach, where the {mu} term is generated directly by non-perturtative effects. The same non-perturbative effect will also retrofit the model of SUSY breaking in such a way that {mu} is at the same scale as masses of the Standard Model superpartners. Because the {mu} term is not directly generated by SUSY breaking effects, there is no associated B{mu} problem. These results are demonstrated in a toy model where a stringy instanton generates {mu}.

  19. Basic problems in controlled trials.

    PubMed Central

    Burkhardt, R; Kienle, G

    1983-01-01

    On the basis of critical discussions which have taken place in recent years in the Federal Republic of Germany, certain methodological, ethical and legal problems arising in relation to controlled trials are discussed. Because of methodological inconsistencies inherent in the experimental approach, the efficacy of a drug must in any case be judged by physicians. This leads to major ethical and even--at least in Germany--legal problems which impose considerable limits on the feasibility of controlled trials in Germany. Editor's note: This paper is written at the invitation of the journal, following the considerable controversy on the ethics of clinical trials in the European Journal of Clinical Pharmacology (8-11). A critical commentary follows the paper with a short response from the authors and a further response from the commentator. PMID:6876102

  20. An archetype hydrogen atmosphere problem

    NASA Technical Reports Server (NTRS)

    Athay, R. G.; Mihalas, D.; Shine, R. A.

    1975-01-01

    Populations for the first three bound states and the continuum of hydrogen are determined for an isothermal hydrostatic atmosphere at 20,000 K. The atmosphere is treated as optically thin in the Balmer and Paschen continua and illuminated by continuum radiation at these wavelengths with prescribed radiation temperatures. The atmosphere is optically thick in the 2-1, 3-1, 3-2 and c-1 transitions. Three stages of approximation are treated: (1) radiative detailed balance in the 2-1, 3-1 and 3-2 transitions, (2) radiative detailed balance in the 3-1 and 3-2 transitions, and (3) all transitions out of detailed balance. The solution of this problem is nontrivial and presents sufficient difficulty to have caused the failure of at least one rather standard technique. The problem is thus a good archetype against which new methods or new implementations of old methods may be tested.

  1. Vortex shedding and Maxwell's problem

    NASA Astrophysics Data System (ADS)

    Michelin, Sebastien; Smith, Stefan Llewellyn

    2006-11-01

    The coupled problem of a flow around a solid body has applications from the fall of objects in a fluid to the computation of forces on wind-exposed structures. A simplified 2D model is proposed here for the interaction between solid bodies and potential flows. Potential flows over sharp edges generate singular velocities at the edges. To satisfy the Kutta condition, vorticity sheets must be shed from the edges to remove these singularities. Here 2D vorticity sheets are represented as discrete point-vortices with monotically varying intensity. From the fluid momentum conservation, an equation of motion for these vortices, the Brown and Michael equation, is derived and mechanical efforts applied by the fluid on the body are computed. The set of dynamical equations obtained for the fluid-body system is closed and is applied to Maxwell's problem of the 2D fall of a plate in an inviscid fluid initially at rest.

  2. Spectroscopic problems in ITER diagnostics

    NASA Astrophysics Data System (ADS)

    Lisitsa, V. S.; Bureyeva, L. A.; Kukushkin, A. B.; Kadomtsev, M. B.; Krupin, V. A.; Levashova, M. G.; Medvedev, A. A.; Mukhin, E. E.; Shurygin, V. A.; Tugarinov, S. N.; Vukolov, K. Yu

    2012-12-01

    Problems of spectroscopic diagnostics of ITER plasma are under consideration. Three types of diagnostics are presented: 1) Balmer lines spectroscopy in the edge and divertor plasmas; 2) Thomson scattering, 3) charge exchange recombination spectroscopy. The Zeeman-Stark structure of line shapes is discussed. The overlapping of isotopes H-D-T spectral line shapes are presented for the SOL and divertor conditions. The polarization measurements of H-alpha spectral lines for H-D mixture on T-10 tokamak are shown in order to separate Zeeman splitting in more details. The problem of plasma background radiation emission for Thomson scattering in ITER is discussed in details. The line shape of P-7 hydrogen spectral line having a wave length close to laser one is presented together with continuum radiation. The charge exchange recombination spectroscopy (CXRS) is discussed in details. The data on Dα, HeII and CVI measurements in CXRS experiments on T-10 tokamak are presented.

  3. Occupational Health Problems of Musicians

    PubMed Central

    Chong, John; Lynden, Melody; Harvey, David; Peebles, Marie

    1989-01-01

    Musicians, as well as other performing artists, may have their careers interrupted by, interfered with, or terminated by occupational health problems involving the neuro-musculoskeletal system. Adverse working conditions, organization, and activity may affect the health of musicians in all age groups and at all levels of performing ability. Instrument-specific health problems are related to excessive force, static loading, repetitive movement, and duration of musical performance. Important risk factors are 1) change in technique or instrument; 2) intense preparation for a performance; 3) preparation of a new and difficult repertoire; and 4) prolonged periods of performance without rest. Treatment protocols and health promotion or disease prevention programs are being developed in collaboration with the performing arts community. ImagesFigure 1Figure 2Figure 3 PMID:21248930

  4. Learning unlearnable problems with perceptrons

    NASA Astrophysics Data System (ADS)

    Watkin, Timothy L. H.; Rau, Albrecht

    1992-03-01

    We study how well perceptrons learn to solve problems for which there is no perfect answer (the usual case), taking as examples a rule with a threshold, a rule in which the answer is not a monotonic function of the overlap between question and teacher, and a rule with many teachers (a ``hard'' unlearnable problem). In general there is a tendency for first-order transitions, even using spherical perceptrons, as networks compromise between conflicting requirements. Some existing learning schemes fail completely-occasionally even finding the worst possible solution; others are more successful. High-temperature learning seems more satisfactory than zero-temperature algorithms and avoids ``overlearning'' and ``overfitting,'' but care must be taken to avoid ``trapping'' in spurious free-energy minima. For some rules examples alone are not enough to learn from, and some prior information is required.

  5. Problems in characterizing barrier performance

    NASA Technical Reports Server (NTRS)

    Jordan, Harry F.

    1988-01-01

    The barrier is a synchronization construct which is useful in separating a parallel program into parallel sections which are executed in sequence. The completion of a barrier requires cooperation among all executing processes. This requirement not only introduces the wait for the slowest process delay which is inherent in the definition of the synchronization, but also has implications for the efficient implementation and measurement of barrier performance in different systems. Types of barrier implementation and their relationship to different multiprocessor environments are described. Then the problem of measuring the performance of barrier implementations on specific machine architecture is discussed. The fact that the barrier synchronization requires the cooperation of all processes makes the problem of performance measurement similarly global. Making non-intrusive measurements of sufficient accuracy can be tricky on systems offering only rudimentary measurement tools.

  6. Public health problems of urbanization.

    PubMed

    Mutatkar, R K

    1995-10-01

    Developing countries have been peasant societies. The cities in traditional societies have been pilgrimage centres, seats of administration and educational centres. These cities had homogeneous relationships with the villages. Industrialization has developed modern megacities whose way of life is heterogeneous with that in the villages. Rural poverty has pushed villagers to the cities, which were never planned to accommodate immigrants. Public health and social problems have arisen lowering the quality of life. Communicable diseases among the urban poor coexist with non-communicable diseases among the comparatively affluent. Problems of pollution, crime and chronic morbidity increase. The NGOs provide relief to the poor and needy but do nothing toward creating an infrastructure for balanced development. The election of women as a result of non-discriminatory legislation provides good ground for hope.

  7. Algorithmic Perspectives on Problem Formulations in MDO

    NASA Technical Reports Server (NTRS)

    Alexandrov, Natalia M.; Lewis, Robert Michael

    2000-01-01

    This work is concerned with an approach to formulating the multidisciplinary optimization (MDO) problem that reflects an algorithmic perspective on MDO problem solution. The algorithmic perspective focuses on formulating the problem in light of the abilities and inabilities of optimization algorithms, so that the resulting nonlinear programming problem can be solved reliably and efficiently by conventional optimization techniques. We propose a modular approach to formulating MDO problems that takes advantage of the problem structure, maximizes the autonomy of implementation, and allows for multiple easily interchangeable problem statements to be used depending on the available resources and the characteristics of the application problem.

  8. Fibonacci's Triangle: A Vehicle for Problem Solving.

    ERIC Educational Resources Information Center

    Ouellette, Hugh

    1979-01-01

    A method for solving certain types of problems is illustrated by problems related to Fibonacci's triangle. The method involves pattern recognition, generalizing, algebraic manipulation, and mathematical induction. (MP)

  9. Context in Mathematics Learning: Problems and Possibilities

    ERIC Educational Resources Information Center

    Lee, Ji-Eun

    2007-01-01

    This article presents an instructional idea that facilitates the students' active participation in the problem analysis process using insufficient or contradictory problem contexts. (Contains 1 figure.)

  10. Two Problems with Table Saws

    ERIC Educational Resources Information Center

    Vautaw, William R.

    2008-01-01

    We solve two problems that arise when constructing picture frames using only a table saw. First, to cut a cove running the length of a board (given the width of the cove and the angle the cove makes with the face of the board) we calculate the height of the blade and the angle the board should be turned as it is passed over the blade. Second, to…

  11. Medical problems from cold exposure

    SciTech Connect

    Dembert, M.L.

    1982-01-01

    Problems resulting from cold exposure can be successfully treated when a coordinated emergency medical transport system and appropriate equipment are available, as well as medical personnel knowledgeable in the management of frostbite and hypothermia. Clinical suspicion of these disorders is essential. Profoundly hypothermic individuals with no recordable vital signs have been resuscitated after controlled, rapid rewarming measures and the use of emergency life-support systems.

  12. A nonlinear supercooled Stefan problem

    NASA Astrophysics Data System (ADS)

    Briozzo, Adriana C.; Natale, Maria F.

    2017-04-01

    We study the supercooled one-phase Stefan problem for a semi-infinite material with temperature-dependent thermal conductivity at the fixed face x=0. We obtain sufficient conditions for data in order to have existence of a solution of similarity type, local in time and finite-time blow-up occurs. This explicit solution is obtained through the unique solution of an integral equation with the time as a parameter.

  13. LORAN-C prediction problems

    NASA Technical Reports Server (NTRS)

    Lukac, C. F.

    1982-01-01

    Control of time and frequency at remote stations and the maintenance of a constant time scale for LORAN-C chains are problems of practical importance. The stability of stations monitoring a LORAN-C chain is analyzed, in particular, those stations monitoring the Northwest Pacific chain. Individual determinations of the quantity, U.S. Naval Observatory Master lock are compared with an averaged value and monitored data.

  14. Aesthetic problems in chemical peeling.

    PubMed

    Goldman, P M; Freed, M I

    1989-09-01

    Questionnaires were mailed to six physicians experienced in chemical peels regarding common problems encountered in the procedure. They are: Thomas H. Alt, M.D., Minneapolis, MN; Samuel J. Stegman, M.D., San Francisco, CA; James J. Stagnone, M.D., Albuquerque, NM; Robert Kotler, M.D., Los Angeles, CA; William H. Beeson, M.D., Indianapolis, IN; and Paul S. Collins, M.D., San Luis Obispo, CA. Their answers are presented in a panel format.

  15. Sleep problems in healthy preadolescents.

    PubMed

    Kahn, A; Van de Merckt, C; Rebuffat, E; Mozin, M J; Sottiaux, M; Blum, D; Hennart, P

    1989-09-01

    Few data currently exist concerning the sleep problems of preadolescents. A parent report questionnaire concerning sleep habits and problems was developed. The questionnaires were completed by the parents of 1000 unscreened elementary school children attending the third, fourth, and fifth grades. The schools were randomly selected from an urban area. Of the 1000 questionnaires, 972 were completed and could be used for statistical analysis. Among the parents, 24% reported sleeping poorly and 12% regularly relied on sedatives to induce sleep. Sleep difficulties lasting more than 6 months were present in 43% of the children. In 14% (132 of 972), sleep latency was longer than 30 minutes, and more than one complete arousal occurred during the night at least two nights per week. The following variables were seen among the poor sleepers: lower parental educational and professional status, parents who were more likely to be divorced or separated, and more noise or light in the rooms were they slept. They also presented a higher incidence of somnambulism, somniloquia, and night fears (nightmares and night terrors) than the children who slept well. Boys who slept poorly were significantly more likely to have insomniac fathers (P less than .010). Regular use of sedatives was described in 4% (5 of 132) of the children who slept poorly. Among the "poor sleepers," 21% (33 of 132) had failed 1 or more years at school. School achievement difficulties were encountered significantly more often among the poor sleepers than among the children without sleep problems (P = .001). Of the families with children suffering from sleep problems, 28% expressed a desire for counseling.(ABSTRACT TRUNCATED AT 250 WORDS)

  16. Benchmark problems in computational aeroacoustics

    NASA Technical Reports Server (NTRS)

    Porter-Locklear, Freda

    1994-01-01

    A recent directive at NASA Langley is aimed at numerically predicting principal noise sources. During my summer stay, I worked with high-order ENO code, developed by Dr. Harold Atkins, for solving the unsteady compressible Navier-Stokes equations, as it applies to computational aeroacoustics (CAA). A CAA workshop, composed of six categories of benchmark problems, has been organized to test various numerical properties of code. My task was to determine the robustness of Atkins' code for these test problems. In one category, we tested the nonlinear wave propagation of the code for the one-dimensional Euler equations, with initial pressure, density, and velocity conditions. Using freestream boundary conditions, our results were plausible. In another category, we solved the linearized two-dimensional Euler equations to test the effectiveness of radiation boundary conditions. Here we utilized MAPLE to compute eigenvalues and eigenvectors of the Jacobian given variable and flux vectors. We experienced a minor problem with inflow and outflow boundary conditions. Next, we solved the quasi one dimensional unsteady flow equations with an incoming acoustic wave of amplitude 10(exp -6). The small amplitude sound wave was incident on a convergent-divergent nozzle. After finding a steady-state solution and then marching forward, our solution indicated that after 30 periods the acoustic wave had dissipated (a period is time required for sound wave to traverse one end of nozzle to other end).

  17. Benchmark problems in computational aeroacoustics

    NASA Astrophysics Data System (ADS)

    Porter-Locklear, Freda

    1994-12-01

    A recent directive at NASA Langley is aimed at numerically predicting principal noise sources. During my summer stay, I worked with high-order ENO code, developed by Dr. Harold Atkins, for solving the unsteady compressible Navier-Stokes equations, as it applies to computational aeroacoustics (CAA). A CAA workshop, composed of six categories of benchmark problems, has been organized to test various numerical properties of code. My task was to determine the robustness of Atkins' code for these test problems. In one category, we tested the nonlinear wave propagation of the code for the one-dimensional Euler equations, with initial pressure, density, and velocity conditions. Using freestream boundary conditions, our results were plausible. In another category, we solved the linearized two-dimensional Euler equations to test the effectiveness of radiation boundary conditions. Here we utilized MAPLE to compute eigenvalues and eigenvectors of the Jacobian given variable and flux vectors. We experienced a minor problem with inflow and outflow boundary conditions. Next, we solved the quasi one dimensional unsteady flow equations with an incoming acoustic wave of amplitude 10(exp -6). The small amplitude sound wave was incident on a convergent-divergent nozzle. After finding a steady-state solution and then marching forward, our solution indicated that after 30 periods the acoustic wave had dissipated (a period is time required for sound wave to traverse one end of nozzle to other end).

  18. Oral health problems and mortality

    PubMed Central

    Kim, Jung Ki; Baker, Lindsey A.; Davarian, Shieva; Crimmins, Eileen

    2013-01-01

    Background/purpose Previous studies have shown the relationship between individual oral health conditions and mortality; however, the relationship between mortality and multiple oral health conditions has not been examined. This study investigates the link between individual oral health problems and oral comorbidity and mortality risk. Materials and methods Data are derived from the National Health and Nutrition Examination Survey 1999–2004, which is linked to the National Death Index for mortality follow-up through 2006. We estimated the risk of mortality among people with three individual oral health conditions—tooth loss, root caries, and periodontitis as well as with oral comorbidity—or having all three conditions. Results Significant tooth loss, root caries, and periodontal disease were associated with increased odds of dying. The relationship between oral health conditions and mortality disappeared when controlling for sociodemographic, health, and/or health behavioral indicators. Having multiple oral health problems was associated with an even higher rate of mortality. Conclusion Individual oral health conditions—tooth loss, root caries, and periodontal disease—were not related to mortality when sociodemographic, health, and/or health behavioral factors were considered, and there was no differential pattern between the three conditions. Multiple oral health problems were associated with a higher risk of dying. PMID:24416472

  19. OPEN PROBLEM: Spatially localized structures in dissipative systems: open problems

    NASA Astrophysics Data System (ADS)

    Knobloch, E.

    2008-04-01

    Stationary spatially localized structures, sometimes called dissipative solitons, arise in many interesting and important applications, including buckling of slender structures under compression, nonlinear optics, fluid flow, surface catalysis, neurobiology and many more. The recent resurgence in interest in these structures has led to significant advances in our understanding of the origin and properties of these states, and these in turn suggest new questions, both general and system-specific. This paper surveys these results focusing on open problems, both mathematical and computational, as well as on new applications.

  20. Sexual problems among married Nigerian women.

    PubMed

    Ojomu, F; Thacher, T; Obadofin, M

    2007-01-01

    We interviewed and examined 293 married women, 15-49 years of age, seeking primary care at a teaching hospital in central Nigeria. One or more sexual problems were identified in 71% of women. The proportion of specific sexual problems was 39% for a desire problem, 40% for an arousal problem, 31% for a sex pain problem and 55% for an orgasmic problem. Poor marital communication, lack of foreplay, Islamic religion and advancing age were independently associated with a desire problem. Absence of foreplay was independently associated with an arousal problem. Lack of foreplay, lower abdominal pain, gynaecological conditions, working outside the home and younger age were independently associated with a sex pain problem. The absence of foreplay, poor marital communication and being a housewife were independently associated with an orgasmic problem. Sexual problems are common among married Nigerian women seeking outpatient care.

  1. Unresolved Problems by Shock Capturing: Taming the Overheating Problem

    NASA Technical Reports Server (NTRS)

    Liou, Meng-Sing

    2012-01-01

    The overheating problem, first observed by von Neumann [1] and later studied extensively by Noh [2] using both Eulerian and Lagrangian formulations, remains to be one of the unsolved problems by shock capturing. It is historically well known to occur when a flow is under compression, such as when a shock wave hits and reflects from a wall or when two streams collides with each other. The overheating phenomenon is also found numerically in a smooth flow undergoing rarefaction created by two streams receding from each other. This is in contrary to one s intuition expecting a decrease in internal energy. The excessive amount in the temperature increase does not reduce by refining the mesh size or increasing the order of accuracy. This study finds that the overheating in the receding flow correlates with the entropy generation. By requiring entropy preservation, the overheating is eliminated and the solution is grid convergent. The shock-capturing scheme, as being practiced today, gives rise to the entropy generation, which in turn causes the overheating. This assertion stands up to the convergence test.

  2. Multigrid Methods for EHL Problems

    NASA Technical Reports Server (NTRS)

    Nurgat, Elyas; Berzins, Martin

    1996-01-01

    In many bearings and contacts, forces are transmitted through thin continuous fluid films which separate two contacting elements. Objects in contact are normally subjected to friction and wear which can be reduced effectively by using lubricants. If the lubricant film is sufficiently thin to prevent the opposing solids from coming into contact and carries the entire load, then we have hydrodynamic lubrication, where the lubricant film is determined by the motion and geometry of the solids. However, for loaded contacts of low geometrical conformity, such as gears, rolling contact bearings and cams, this is not the case due to high pressures and this is referred to as Elasto-Hydrodynamic Lubrication (EHL) In EHL, elastic deformation of the contacting elements and the increase in fluid viscosity with pressure are very significant and cannot be ignored. Since the deformation results in changing the geometry of the lubricating film, which in turn determines the pressure distribution, an EHL mathematical model must simultaneously satisfy the complex elasticity (integral) and the Reynolds lubrication (differential) equations. The nonlinear and coupled nature of the two equations makes numerical calculations computationally intensive. This is especially true for highly loaded problems found in practice. One novel feature of these problems is that the solution may exhibit sharp pressure spikes in the outlet region. To this date both finite element and finite difference methods have been used to solve EHL problems with perhaps greater emphasis on the use of the finite difference approach. In both cases, a major computational difficulty is ensuring convergence of the nonlinear equations solver to a steady state solution. Two successful methods for achieving this are direct iteration and multigrid methods. Direct iteration methods (e.g Gauss Seidel) have long been used in conjunction with finite difference discretizations on regular meshes. Perhaps one of the best examples of

  3. The Hard Problem of Cooperation

    PubMed Central

    Eriksson, Kimmo; Strimling, Pontus

    2012-01-01

    Based on individual variation in cooperative inclinations, we define the “hard problem of cooperation” as that of achieving high levels of cooperation in a group of non-cooperative types. Can the hard problem be solved by institutions with monitoring and sanctions? In a laboratory experiment we find that the answer is affirmative if the institution is imposed on the group but negative if development of the institution is left to the group to vote on. In the experiment, participants were divided into groups of either cooperative types or non-cooperative types depending on their behavior in a public goods game. In these homogeneous groups they repeatedly played a public goods game regulated by an institution that incorporated several of the key properties identified by Ostrom: operational rules, monitoring, rewards, punishments, and (in one condition) change of rules. When change of rules was not possible and punishments were set to be high, groups of both types generally abided by operational rules demanding high contributions to the common good, and thereby achieved high levels of payoffs. Under less severe rules, both types of groups did worse but non-cooperative types did worst. Thus, non-cooperative groups profited the most from being governed by an institution demanding high contributions and employing high punishments. Nevertheless, in a condition where change of rules through voting was made possible, development of the institution in this direction was more often voted down in groups of non-cooperative types. We discuss the relevance of the hard problem and fit our results into a bigger picture of institutional and individual determinants of cooperative behavior. PMID:22792282

  4. Genetics problem solving and worldview

    NASA Astrophysics Data System (ADS)

    Dale, Esther

    The research goal was to determine whether worldview relates to traditional and real-world genetics problem solving. Traditionally, scientific literacy emphasized content knowledge alone because it was sufficient to solve traditional problems. The contemporary definition of scientific literacy is, "The knowledge and understanding of scientific concepts and processes required for personal decision-making, participation in civic and cultural affairs and economic productivity" (NRC, 1996). An expanded definition of scientific literacy is needed to solve socioscientific issues (SSI), complex social issues with conceptual, procedural, or technological associations with science. Teaching content knowledge alone assumes that students will find the scientific explanation of a phenomenon to be superior to a non-science explanation. Formal science and everyday ways of thinking about science are two different cultures (Palmer, 1999). Students address this rift with cognitive apartheid, the boxing away of science knowledge from other types of knowledge (Jedege & Aikenhead, 1999). By addressing worldview, cognitive apartheid may decrease and scientific literacy may increase. Introductory biology students at the University of Minnesota during fall semester 2005 completed a written questionnaire-including a genetics content-knowledge test, four genetic dilemmas, the Worldview Assessment Instrument (WAI) and some items about demographics and religiosity. Six students responded to the interview protocol. Based on statistical analysis and interview data, this study concluded the following: (1) Worldview, in the form of metaphysics, relates to solving traditional genetic dilemmas. (2) Worldview, in the form of agency, relates to solving traditional genetics problems. (3) Thus, worldview must be addressed in curriculum, instruction, and assessment.

  5. The hard problem of cooperation.

    PubMed

    Eriksson, Kimmo; Strimling, Pontus

    2012-01-01

    Based on individual variation in cooperative inclinations, we define the "hard problem of cooperation" as that of achieving high levels of cooperation in a group of non-cooperative types. Can the hard problem be solved by institutions with monitoring and sanctions? In a laboratory experiment we find that the answer is affirmative if the institution is imposed on the group but negative if development of the institution is left to the group to vote on. In the experiment, participants were divided into groups of either cooperative types or non-cooperative types depending on their behavior in a public goods game. In these homogeneous groups they repeatedly played a public goods game regulated by an institution that incorporated several of the key properties identified by Ostrom: operational rules, monitoring, rewards, punishments, and (in one condition) change of rules. When change of rules was not possible and punishments were set to be high, groups of both types generally abided by operational rules demanding high contributions to the common good, and thereby achieved high levels of payoffs. Under less severe rules, both types of groups did worse but non-cooperative types did worst. Thus, non-cooperative groups profited the most from being governed by an institution demanding high contributions and employing high punishments. Nevertheless, in a condition where change of rules through voting was made possible, development of the institution in this direction was more often voted down in groups of non-cooperative types. We discuss the relevance of the hard problem and fit our results into a bigger picture of institutional and individual determinants of cooperative behavior.

  6. [Addiction therapy. Limits, problems, perspectives].

    PubMed

    Kalapos, Miklós Péter

    2014-01-01

    In health care, tending is a process, which offers for the patients a continuous watching on, a control, a treatment, and the prevention of worsening of their medical status as well as the reduction of their complaints. In the article, some fundamental segments of tending in addictology are reviewed, particularly paying attention to whom, how, where and how long to take care. On the basis of literature, the author stresses whatever method is used to treat addict patients it is more beneficial to society than the avoidance of any intervention due to the negligence of the problem. Addictology has lost a lot from its power in Hungary. The author recommends the introduction of the methods of health quality assurance to decrease the effect of negative trends seen in addictology. The paper also deals with special patient groups including homeless clients, adolescents, elderly and pregnant patients as well as health care professionals. The author critically mentions the double communication of society, the dual-face character of politics and has the opinion that competences are not clear making the situation confused. As a mistake of the point of view is it regarded that the addictological problems are classified as to belonging to the authority of psychiatry. It is emphasized that multidisciplinary approach is needed to understand the problem and to treat the client. General screening for addictological diseases does not seem possible in the light of low capacity of the system, but the screening of adolescents and pregnant women is definitely recommended. And finally, a financial support for medicines to prevent craving, a moratorium for the continuous changing of rules and law, the sponsoring of harm reduction programs as well as a better utilization of opportunities offered by local drug coordinating boards are proposed.

  7. King Oedipus and the Problem Solving Process.

    ERIC Educational Resources Information Center

    Borchardt, Donald A.

    An analysis of the problem solving process reveals at least three options: (1) finding the cause, (2) solving the problem, and (3) anticipating potential problems. These methods may be illustrated by examining "Oedipus Tyrannus," a play in which a king attempts to deal with a problem that appears to be beyond his ability to solve, and…

  8. Problem Solving with the Elementary Youngster.

    ERIC Educational Resources Information Center

    Swartz, Vicki

    This paper explores research on problem solving and suggests a problem-solving approach to elementary school social studies, using a culture study of the ancient Egyptians and King Tut as a sample unit. The premise is that problem solving is particularly effective in dealing with problems which do not have one simple and correct answer but rather…

  9. The Prisoner Problem--A Generalization.

    ERIC Educational Resources Information Center

    Gannon, Gerald E.; Martelli, Mario U.

    2000-01-01

    Presents a generalization to the classic prisoner problem, which is inherently interesting and has a solution within the reach of most high school mathematics students. Suggests the problem as a way to emphasize to students the final step in a problem-solver's tool kit, considering possible generalizations when a particular problem has been…

  10. Problem Solving with Generic Algorithms and Computers.

    ERIC Educational Resources Information Center

    Larson, Jay

    Success in using a computer in education as a problem-solving tool requires a change in the way of thinking or of approaching a problem. An algorithm, i.e., a finite step-by-step solution to a problem, can be designed around the data processing concepts of input, processing, and output to provide a basis for classifying problems. If educators…

  11. Problem-Solving Analysis and Business Writing.

    ERIC Educational Resources Information Center

    Myrsiades, Linda Suny

    Problem solving skills such as patterning facts, locating problems, separating problems and solutions, and presenting effective written products are essential to success in the business community. Facts can be patterned using a grid relating a problem's effect at the individual, group, situational, and organizational level. Such a grid tests each…

  12. Tour of a Simple Trigonometry Problem

    ERIC Educational Resources Information Center

    Poon, Kin-Keung

    2012-01-01

    This article focuses on a simple trigonometric problem that generates a strange phenomenon when different methods are applied to tackling it. A series of problem-solving activities are discussed, so that students can be alerted that the precision of diagrams is important when solving geometric problems. In addition, the problem-solving plan was…

  13. Man and His Technology: Problems and Issues.

    ERIC Educational Resources Information Center

    Piel, E. J.; Truxal, John G.

    This book looks at a sampling of notable socio-technical problems within a rational context. It seeks to determine if problems exist with recent decisions in the application of technology; how threatening any problems may be; the source of problems; and examines alternatives available to the nation. The broad goal of this rational consideration is…

  14. Disciplinary Foundations for Solving Interdisciplinary Scientific Problems

    ERIC Educational Resources Information Center

    Zhang, Dongmei; Shen, Ji

    2015-01-01

    Problem-solving has been one of the major strands in science education research. But much of the problem-solving research has been conducted on discipline-based contexts; little research has been done on how students, especially individuals, solve interdisciplinary problems. To understand how individuals reason about interdisciplinary problems, we…

  15. Journey toward Teaching Mathematics through Problem Solving

    ERIC Educational Resources Information Center

    Sakshaug, Lynae E.; Wohlhuter, Kay A.

    2010-01-01

    Teaching mathematics through problem solving is a challenge for teachers who learned mathematics by doing exercises. How do teachers develop their own problem solving abilities as well as their abilities to teach mathematics through problem solving? A group of teachers began the journey of learning to teach through problem solving while taking a…

  16. Research on Computers and Problem Solving.

    ERIC Educational Resources Information Center

    Burton, John K.; And Others

    1988-01-01

    Eight articles review and report on research involving computers and problem solving skills. Topics discussed include research design; problem solving skills and programing languages, including BASIC and LOGO; computer anxiety; diagnostic programs for arithmetic problems; and relationships between ability and problem solving scores and between…

  17. Teaching Problem Solving through Children's Literature.

    ERIC Educational Resources Information Center

    Forgan, James W.

    This book helps general and special education teachers empower students in grades K-4 to independently solve problems by teaching them how characters in children's literature books solved similar problems. Students are also taught a problem solving strategy that they can apply to solve problems in any situation. The book contains ready-to-use…

  18. From Kepler problem to skyrmions

    NASA Astrophysics Data System (ADS)

    Mazilu, Nicolae; Agop, Maricel; Gatu, Irina; Iacob, Dan Dezideriu; Ghizdovăt, Vlad

    2016-05-01

    The classical treatment of the Kepler problem leaves room for the description of the space region of the central body by a hyperbolic geometry. If the correspondence between the empty space and the space filled with matter is taken to be a harmonic mapping, then the region of atomic nucleus, like the one of the Sun for the planetary system proper, is described by hyperbolic skyrmions. This fact makes possible the description of the nuclear matter within framework of general relativity. The classical “hedgehog” solution for skyrmions can then be classically interpreted in terms of the characterizations of intra-nuclear forces.

  19. Combinatorial Algorithms for Optimization Problems

    DTIC Science & Technology

    1991-06-01

    since it is not known whether the problem has an SP algo- rithm. 1.3 Notation We use boldface notation for vectors and matrices . Suppose U is a matrix...Af the set of all 1-tuples of elements of Ai. A nxI the set of all m x n matrices whose entries are elements of Ai. We use the notation R, R+, Q, Z...X, Y E F and a > 0, 6 0 0, az +RY E F. A cone is pointed iff it does not contain a linear subspace. * The lineality space of a cone F is the largest

  20. Solving the Dark Matter Problem

    ScienceCinema

    Baltz, Ted

    2016-07-12

    Cosmological observations have firmly established that the majority of matter in the universe is of an unknown type, called 'dark matter'. A compelling hypothesis is that the dark matter consists of weakly interacting massive particles (WIMPs) in the mass range around 100 GeV. If the WIMP hypothesis is correct, such particles could be created and studied at accelerators. Furthermore they could be directly detected as the primary component of our galaxy. Solving the dark matter problem requires that the connection be made between the two. We describe some theoretical and experimental avenues that might lead to this connection.

  1. [Some problems of space medicine].

    PubMed

    Gurovskiĭ, N N; Egorov, A D

    1976-01-01

    The paper discusses the problems to be resolved by space medicine and the main stages in the development of this branch of science, beginning with the vertical launches of rockets and ending with the flights of orbital stations. On the basis of ground-based simulation experiments and real space flights it presents a classification of the major symptomocomplexes that may occur inflight. The paper describes the main stages of adaptation to weightlessness and physiological changes in the weightless state. The paper also outlines further pathways in the development of space medicine.

  2. The Born transmission eigenvalue problem

    NASA Astrophysics Data System (ADS)

    Cakoni, Fioralba; Colton, David; Rezac, Jacob D.

    2016-10-01

    In this paper we study the distribution of transmission eigenvalues in the complex plane for obstacles whose contrast is small in magnitude. We use a first order approximation of the refractive index to derive and study an approximate interior transmission problem. In the case of spherically stratified media, we prove existence and discreteness of transmission eigenvalues and derive a condition under which the complex part of transmission eigenvalues cannot lie in a strip parallel to the real axis. For obstacles with general shape, we demonstrate that if transmission eigenvalues exist then they form a discrete set.

  3. Solving the Telomere Replication Problem

    PubMed Central

    Maestroni, Laetitia; Matmati, Samah; Coulon, Stéphane

    2017-01-01

    Telomeres are complex nucleoprotein structures that protect the extremities of linear chromosomes. Telomere replication is a major challenge because many obstacles to the progression of the replication fork are concentrated at the ends of the chromosomes. This is known as the telomere replication problem. In this article, different and new aspects of telomere replication, that can threaten the integrity of telomeres, will be reviewed. In particular, we will focus on the functions of shelterin and the replisome for the preservation of telomere integrity. PMID:28146113

  4. Problems of reconstruction during pancreatoduodenectomy.

    PubMed

    Sakorafas, G H; Friess, H; Balsiger, B M; Büchler, M W; Sarr, M G

    2001-01-01

    Pancreatoduodenectomy may be a difficult operation, not only during the resectional part of the procedure, but also during reconstruction. Usually, these problems are due to local conditions of the organs/tissues, such as small diameter of the common bile duct or pancreatic duct, friable soft pancreas, vascular anomalies, etc. Reconstruction may also be problematic because of the hemodynamic instability of the patient during surgery (subsequent to massive hemorrhage), and in those unusual cases, delayed reconstruction may be a life-saving, wise choice.

  5. Diagnostic problems in oral pathology.

    PubMed

    Dunlap, C L; Barker, B F

    1985-02-01

    Diagnostic problems within the oral cavity may be associated with lesions of the odontogenic apparatus, salivary glands, bone, mucosa, and connective tissue. Some lesions are unique to the oral cavity, others have a systemic distribution. Several unique and controversial lesions have been selected for discussion, including (1) necrotizing sialometaplasia, a benign salivary gland disease easily mistaken for malignancy; (2) verrucous lesions including verrucous carcinoma, verrucous hyperplasia, and papillary carcinoma; (3) spindle-cell carcinoma, which is often confused with sarcoma; (4) named and unnamed embryonic rests, which may resemble metastatic carcinomas; (5) dental pulp mistaken for odontogenic myxoma; and (6) granular cell tumor with associated pseudoepitheliomatous hyperplasia.

  6. The anterior open bite problem (infraclusion).

    PubMed

    Champagne, M

    1995-06-01

    Anterior open bite is a major orthodontic problem that is very difficult to treat (Fig. 1). It may not be the most frequent problem but it is a major functional problem. Quite often it is very difficult to correct an anterior open bite problem and even more difficult to treat in an adult after growth. Most of the time anterior open bite is a myofunctional problem related to a bad habit like thumb or finger sucking and/or is related to a breathing and swallowing problem. How can we understand the functional open bite problem? What are the available treatment options? This article will try to answer some of these questions.

  7. [Clinical problems in medical mycology: problem number 45].

    PubMed

    Santiso, Gabriela; Arechavala, Alicia; Maiolo, Elena; Balarezo Juncos, Silvia; Fernández, Marisa Liliana; Messina, Fernando; Bianchi, Mario; Negroni, Ricardo

    2013-01-03

    A 43 year-old diabetic woman, who suffered chronic cough and brown expectoration, is presented in this clinical problem. X-ray exam and CT thorax scan showed a cavitary lung lesion, located at the upper field of the left lung. This lesion had 5 cm in diameter, with a thick wall and a spherical shadow inside. The diagnosis of chronic cavitary pulmonary coccidioidomycosis was based on the isolation of Coccidioides sp. from cultures of expectoration and bronchoalveolar lavage, and the detection of specific antibodies in immunodiffusion test and counterimmunoelectrophoresis with coccidiodin. Her diabetes was not well controlled. She was treated with intravenous amphotericin B and oral itraconazole, with good clinical response; after four months of treatment the patient abandoned clinical controls. We suppose that the patient presented a coccidioidal fungus ball, inside a chronic cavitary lesion due to pulmonary coccidiodomycosis. She came from an endemic zone of coccidioidomycosis in the Northwest of the Argentine Republic (Catamarca Province).

  8. Problem-Elephant Translocation: Translocating the Problem and the Elephant?

    PubMed Central

    Fernando, Prithiviraj; Leimgruber, Peter; Prasad, Tharaka; Pastorini, Jennifer

    2012-01-01

    Human-elephant conflict (HEC) threatens the survival of endangered Asian elephants (Elephas maximus). Translocating “problem-elephants” is an important HEC mitigation and elephant conservation strategy across elephant range, with hundreds translocated annually. In the first comprehensive assessment of elephant translocation, we monitored 16 translocations in Sri Lanka with GPS collars. All translocated elephants were released into national parks. Two were killed within the parks where they were released, while all the others left those parks. Translocated elephants showed variable responses: “homers” returned to the capture site, “wanderers” ranged widely, and “settlers” established home ranges in new areas soon after release. Translocation caused wider propagation and intensification of HEC, and increased elephant mortality. We conclude that translocation defeats both HEC mitigation and elephant conservation goals. PMID:23236404

  9. Dermatological problems of the puberty

    PubMed Central

    Brzezińska-Wcisło, Ligia

    2013-01-01

    Puberty is a period of life between childhood and adulthood. It is characterized by many changes in morphology and appearance of the body (biological maturation), in the psyche – development of personality (psychological maturation), and in the attitude towards one's own and the opposite sex (psychosexual maturation), and in the social role (social maturation). Dermatological problems of adolescence are mainly related to fluctuations in hormone levels, mainly androgens. They include acne, hair problems and excessive sweating. Acne vulgaris is the most frequently diagnosed dermatosis in patients aged between 11 and 30 years. It is believed that it affects about 80% of persons in this age group or even, taking into account lesions of low intensity, 100% of young people. Excessive sweating is a condition characterised by excessive production of sweat, resulting from high activity of sweat glands. The sweat glands are localised in almost all areas of the body surface but on the hands, feet, armpits and around the groin they are found at the highest density. Seborrhoeic dermatitis of the scalp is a chronic, relapsing, inflammatory dermatosis, which currently affects about 5% of the population. It affects mostly young people, particularly men. PMID:24278071

  10. Specialty functions singularity mechanics problems

    NASA Technical Reports Server (NTRS)

    Sarigul, Nesrin

    1989-01-01

    The focus is in the development of more accurate and efficient advanced methods for solution of singular problems encountered in mechanics. At present, finite element methods in conjunction with special functions, boolean sum and blending interpolations are being considered. In dealing with systems which contain a singularity, special finite elements are being formulated to be used in singular regions. Further, special transition elements are being formulated to couple the special element to the mesh that models the rest of the system, and to be used in conjunction with 1-D, 2-D and 3-D elements within the same mesh. Computational simulation with a least squares fit is being utilized to construct special elements, if there is an unknown singularity in the system. A novel approach is taken in formulation of the elements in that: (1) the material properties are modified to include time, temperature, coordinate and stress dependant behavior within the element; (2) material properties vary at nodal points of the elements; (3) a hidden-symbolic computation scheme is developed and utilized in formulating the elements; and (4) special functions and boolean sum are utilized in order to interpolate the field variables and their derivatives along the boundary of the elements. It may be noted that the proposed methods are also applicable to fluids and coupled problems.

  11. [Intellectual honesty in abortion problems].

    PubMed

    Werner, M

    1991-04-03

    A pastor comments on the recent ruling by the Swedish Department of Health and Social Affairs that the remains of an abortion should be "treated respectfully"--cremated or buried in a cemetery. This decision results from recognition on the part of the government and the medical establishment that a growing segment of public opinion agrees that the fetus is a human being. The new rules mean, though, that a fetus becomes human only upon its death. Logically, an abortion that is respectfully performed ought not to be performed at all. This is the fundamental problem with abortion, and no amount of arbitrary boundary drawing at various levels of supposed capability for survival at the 12th, the 18th, or the 24th week of pregnancy will alter the fact. It is necessary to face the problem with complete intellectual honesty and say that a fetus is a human being no matter what its age, but that voluntary abortion is also a social necessity. Only then can society find another abortion policy, one that recognizes that late abortions are hard to distinguish from births. The Swedish abortion policy must reflect honest facts, rather than etiological legends, preconceived ideas for which arguments must be found afterward.

  12. Laughter, communication problems and dementia.

    PubMed

    Lindholm, Camilla

    2008-01-01

    This article investigates how the elderly with dementia and their professional caregivers use laughter as a device to deal with problems related to language production and comprehension. The data consist of two game-playing situations, used to engage the elderly people in memory work. The article shows how the elderly patients recurrently laugh to acknowledge communication difficulties and to show awareness of their potential non-competency. The professional caregivers are shown to use slightly different strategies for responding to laughter segments initiated by the patients, either making the shortcomings part of the conversation or avoiding referring to the lapse explicitly. The laughter strategies used by the patients are compared to those reported in the CA-literature on laughter. It is well known that laughter is used in sequences of trouble and delicacy in both ordinary and institutional contexts, but my study shows that speakers with dementia laugh when they encounter problems related to language production and comprehension. This functional expansion in relation to premorbid occurrence is evidence that laughter fits the definition of compensatory behaviour utilized to overcome communication barriers. Certain conversational skills are preserved in individuals with dementia, but due to their cognitive impairment these resources are utilized in a slightly different way than by healthy speakers.

  13. Community-powered problem solving.

    PubMed

    Gouillart, Francis; Billings, Douglas

    2013-04-01

    Traditionally, companies have managed their constituencies with specific processes: marketing to customers, procuring from vendors, developing HR policies for employees, and so on. The problem is, such processes focus on repeatability and compliance, so they can lead to stagnation. Inviting your constituencies to collectively help you solve problems and exploit opportunities--"co-creation"--is a better approach. It allows you to continually tap the skills and insights of huge numbers of stakeholders and develop new ways to produce value for all. The idea is to provide stakeholders with platforms (physical and digital forums) on which they can interact, get them to start exploring new experiences and connections, and let the system grow organically. A co-creation initiative by a unit of Becton, Dickinson and Company demonstrates how this works. A global leader in syringes, BD set out to deepen its ties with hospital customers and help them reduce the incidence of infections from unsafe injection and syringe disposal practices. The effort began with a cross-functional internal team, brought in the hospital procurement and supply managers BD had relationships with, and then reached out to hospitals' infection-prevention and occupational health leaders. Eventually product designers, nurses, sustainability staffers, and even hospital CFOs were using the platform, contributing data that generated new best practices and reduced infections.

  14. Population problem in third world.

    PubMed

    Joshi, N C

    1979-04-01

    Since numerous variables influence this growth rate, a holistic approach to the problem is mandatory. Fertility rates in developing countries remain high, not as a result of irrational behavior on the part of the people living in these countries, but as a result of their rational response to high infant mortality rates. Fertility rates will remain high unless the educational, health, and social environment in which these families live is improved. Economic development and population growth are intimately related. Development reduces the death rate resulting in increased population growth, which in turn reduces per capita income. In the developed nations, economic development occurred along with the development of new technologies and the reduction in mortality; therefore, population growth created an effective demand which further stimulated economic development. In developing countries the situation is different. Reduced mortality, the introduction of labor saving technology, and the high consumption aspirations derived from contact with capitalistic countries, have preceded economic development. Given the highly complex nature of the population problem, efforts must be made on many fronts including: 1) family planning promotion; 2) improvements in education, health, and social conditions for high fertility populations; 3) enhancement of worker skills; 4) rapid progress in technology; 5) greater capital accumulation and 5) economic reorganization.

  15. Ignimbrite types and ignimbrite problems

    NASA Astrophysics Data System (ADS)

    Walker, George P. L.

    1983-09-01

    A spectrum of ignimbrite emplacement types exists, ranging from the "conventional" high-aspect ratio (H.A.R.I.) type, emplaced relatively quietly and passively in valleys, to the low-aspect ratio (L.A.R.I.) type, emplaced cataclysmically. Features of the L.A.R.I., such as a remarkable ability to scale mountains and cross open water and a strong fines-depletion of part of their deposits, stem from a high flow velocity which may result from an extremely high magma discharge rate. Being less rare than large-volume H.A.R.I. eruptions covering the same area, L.A.R.I. eruptions are a much more immediate volcanic hazard. Being thin and inconspicuous, a L.A.R.I. may easily be overlooked when determining the past record of a volcano. Another ignimbrite spectrum depends on variations in particle viscosity during emplacement and extends from the low-grade (water-cooled?) ignimbrite which is totally non-welded even if >50 m thick, to the high-grade (superheated?) one which is densely welded even if <50 m thick. Problems of air-cooling and water-cooling of ash flows need to be tackled, and it may be necessary to recognize strongly cooled ash flows which were emplaced in part at <100°C. One problem of ignimbrite eruptions is the origin of the extensive associated ash fall, comparable in volume to the ignimbrite. This ash may be: (a) pre-ignimbrite Plinian pumice; (b) co-ignimbrite ash, containing material lost from both the eruptive column and ash flow; (c) phreatoplinian, due to the entry of significant amounts of water into the vent; (d) phreatoplinian co-ignimbrite, due to explosions at rootless vents where ash flows enter water from land. Another problem is the origin of associated well-sorted and sometimes wavy-bedded deposits. These deposits may be from: (a) base surges, related to either the collapsing column or entry of water to the vent; (b) base surges, due to explosions at rootless vents where ash flows enter water from land; (c) fines depletion in, and deposition

  16. Selected Problems in Stellar Evolution

    NASA Astrophysics Data System (ADS)

    Swenson, Fritz James

    Three long standing "problems" for stellar evolution are addressed either directly or indirectly. Weakly interacting massive particles (WIMPs) have been proposed as a solution to the "solar neutrino problem" but numerical instabilities have hampered the analysis of their impact on solar and stellar models. These instabilities are analyzed and resolved. If WIMPs exist and they solve the solar neutrino problem, then they will affect the deduced ages of globular clusters. It is shown that WIMPs can reduce globular cluster age estimates, which are an important factor in constraining cosmological models. The lithium depletion observed in the Sun and stars (particularly in the Hyades cluster) has resisted a satisfactory explanation for roughly 25 years. Two mechanisms for depleting lithium are investigated: lithium dilution through main-sequence mass-loss and lithium burning occurring during PMS evolution. A thorough investigation of the mass-loss mechanism shows that it cannot be responsible for the pattern of lithium depletion seen in the Hyades G- and K-dwarfs, but that it could potentially explain (though in an ad hoc fashion) the depletion seen in open cluster F-dwarfs and in the Sun. It is shown that the PMS lithium burning mechanism does appear to be the explanation of the lithium depletion seen in Hyades G- and K-dwarfs (the very recent OPAL opacities are fundamental to this conclusion), but it apparently cannot completely explain the depletion seen in the Sun (although it is a significant contributor). Extensively investigated is the impact of opacity changes (including OPAL opacities) on solar PMS lithium burning and on the structure of solar models, particularly with regard to the discrepancy between the depth of the convective zone as determined from solar oscillations and that deduced from models. Also included in the thesis is a discussion outlining why observations of lithium depletion in the G- and K-stars of young clusters (ages less than {~}5 times 10

  17. New Existence Conditions for Order Complementarity Problems

    NASA Astrophysics Data System (ADS)

    Németh, S. Z.

    2009-09-01

    Complementarity problems are mathematical models of problems in economics, engineering and physics. A special class of complementarity problems are the order complementarity problems [2]. Order complementarity problems can be applied in lubrication theory [6] and economics [1]. The notion of exceptional family of elements for general order complementarity problems in Banach spaces will be introduced. It will be shown that for general order complementarity problems defined by completely continuous fields the problem has either a solution or an exceptional family of elements (for other notions of exceptional family of elements see [1, 2, 3, 4] and the related references therein). This solves a conjecture of [2] about the existence of exceptional family of elements for order complementarity problems. The proof can be done by using the Leray-Schauder alternative [5]. An application to integral operators will be given.

  18. Understanding Undergraduates’ Problem-Solving Processes †

    PubMed Central

    Nehm, Ross H.

    2010-01-01

    Fostering effective problem-solving skills is one of the most longstanding and widely agreed upon goals of biology education. Nevertheless, undergraduate biology educators have yet to leverage many major findings about problem-solving processes from the educational and cognitive science research literatures. This article highlights key facets of problem-solving processes and introduces methodologies that may be used to reveal how undergraduate students perceive and represent biological problems. Overall, successful problem-solving entails a keen sensitivity to problem contexts, disciplined internal representation or modeling of the problem, and the principled management and deployment of cognitive resources. Context recognition tasks, problem representation practice, and cognitive resource management receive remarkably little emphasis in the biology curriculum, despite their central roles in problem-solving success. PMID:23653710

  19. Automated formulation of constraint satisfaction problems

    SciTech Connect

    Sabin, M.; Freuder, E.C.

    1996-12-31

    A wide variety of problems can be represented as constraint satisfaction problems (CSPs), and once so represented can be solved by a variety of effective algorithms. However, as with other powerful, general Al problem solving methods, we must still address the task of moving from a natural statement of the problem to a formulation of the problem as a CSP. This research addresses the task of automating this problem formulation process, using logic puzzles as a testbed. Beyond problem formulation per se, we address the issues of effective problem formulation, i.e. finding formulations that support more efficient solution, as well as incremental problem formulation that supports reasoning from partial information and are congenial to human thought processes.

  20. Theory of the decision/problem state

    NASA Technical Reports Server (NTRS)

    Dieterly, D. L.

    1980-01-01

    A theory of the decision-problem state was introduced and elaborated. Starting with the basic model of a decision-problem condition, an attempt was made to explain how a major decision-problem may consist of subsets of decision-problem conditions composing different condition sequences. In addition, the basic classical decision-tree model was modified to allow for the introduction of a series of characteristics that may be encountered in an analysis of a decision-problem state. The resulting hierarchical model reflects the unique attributes of the decision-problem state. The basic model of a decision-problem condition was used as a base to evolve a more complex model that is more representative of the decision-problem state and may be used to initiate research on decision-problem states.

  1. Neurological problems of jazz legends.

    PubMed

    Pearl, Phillip L

    2009-08-01

    A variety of neurological problems have affected the lives of giants in the jazz genre. Cole Porter courageously remained prolific after severe leg injuries secondary to an equestrian accident, until he succumbed to osteomyelitis, amputations, depression, and phantom limb pain. George Gershwin resisted explanations for uncinate seizures and personality change and herniated from a right temporal lobe brain tumor, which was a benign cystic glioma. Thelonious Monk had erratic moods, reflected in his pianism, and was ultimately mute and withdrawn, succumbing to cerebrovascular events. Charlie Parker dealt with mood lability and drug dependence, the latter emanating from analgesics following an accident, and ultimately lived as hard as he played his famous bebop saxophone lines and arpeggios. Charles Mingus hummed his last compositions into a tape recorder as he died with motor neuron disease. Bud Powell had severe posttraumatic headaches after being struck by a police stick defending Thelonious Monk during a Harlem club raid.

  2. The 3He Supply Problem

    SciTech Connect

    Kouzes, Richard T.

    2009-05-01

    One of the main uses for 3He is in gas proportional counters for neutron detection. Radiation portal monitors deployed for homeland security and non-proliferation use such detectors. Other uses of 3He are for research detectors, commercial instruments, well logging detectors, dilution refrigerators, for targets or cooling in nuclear research, and for basic research in condensed matter physics. The US supply of 3He comes almost entirely from the decay of tritium used in nuclear weapons by the US and Russia. A few other countries contribute a small amount to the world’s 3He supply. Due to the large increase in use of 3He for homeland security, the supply has dwindled, and can no longer meet the demand. This white paper reviews the problems of supply, utilization, and alternatives.

  3. [Arsenic as an environmental problem].

    PubMed

    Jensen, K

    2000-12-04

    Chronic exposure to arsenic through drinking water is known in different continents. Arsenic compounds from disintegrating rock may be solubilized after reduction by organic material, and harmful concentrations of arsenic may be found in surface water as well as in water from drilled wells. Because of well drilling since the sixties in the Ganges delta numerous millions of people have been exposed to toxic amounts, and hundreds of thousands demonstrate signs of chronic poisoning. A changed water technology and chemical precipitation of arsenic in the drinking water can reduce the size of the problem, but the late sequelae i.e. malignant disease are incalculable. Indications for antidotal treatment of exposed individuals have not yet been outlined.

  4. Stabilisation problem in biaxial platform

    NASA Astrophysics Data System (ADS)

    Lindner, Tymoteusz; Rybarczyk, Dominik; Wyrwał, Daniel

    2016-12-01

    The article describes investigation of rolling ball stabilization problem on a biaxial platform. The aim of the control system proposed here is to stabilize ball moving on a plane in equilibrium point. The authors proposed a control algorithm based on cascade PID and they compared it with another control method. The article shows the results of the accuracy of ball stabilization and influence of applied filter on the signal waveform. The application used to detect the ball position measured by digital camera has been written using a cross platform .Net wrapper to the OpenCV image processing library - EmguCV. The authors used the bipolar stepper motor with dedicated electronic controller. The data between the computer and the designed controller are sent with use of the RS232 standard. The control stand is based on ATmega series microcontroller.

  5. Teaching DICOM by problem solving.

    PubMed

    Noumeir, Rita; Pambrun, Jean-François

    2012-10-01

    The Digital Imaging and Communications in Medicine (DICOM) is the standard for encoding and communicating medical imaging information. It is used in radiology as well as in many other imaging domains such as ophthalmology, dentistry, and pathology. DICOM information objects are used to encode medical images or information about the images. Their usage outside of the imaging department is increasing, especially with the sharing of medical images within Electronic Health Record systems. However, learning DICOM is long and difficult because it defines and uses many specific abstract concepts that relate to each other. In this paper, we present an approach, based on problem solving, for teaching DICOM as part of a graduate course on healthcare information. The proposed approach allows students with diversified background and no software development experience to grasp a large breadth of knowledge in a very short time.

  6. Adaptive sampling for noisy problems

    SciTech Connect

    Cantu-Paz, E

    2004-03-26

    The usual approach to deal with noise present in many real-world optimization problems is to take an arbitrary number of samples of the objective function and use the sample average as an estimate of the true objective value. The number of samples is typically chosen arbitrarily and remains constant for the entire optimization process. This paper studies an adaptive sampling technique that varies the number of samples based on the uncertainty of deciding between two individuals. Experiments demonstrate the effect of adaptive sampling on the final solution quality reached by a genetic algorithm and the computational cost required to find the solution. The results suggest that the adaptive technique can effectively eliminate the need to set the sample size a priori, but in many cases it requires high computational costs.

  7. European Archaeomagnetism: Progress and Problems

    NASA Astrophysics Data System (ADS)

    Evans, M. E.; Hoye, G.

    2009-05-01

    Much progress has been made since the seminal work of Giuseppe Folgheraiter (1856-1913) in the late 19th century. So much so that recent advances now make it possible to draw up complete isogonic and isoclinic maps for Europe and adjacent areas spanning the last three millennia (Pavon-Carrasco et al., 2009). Results based on multiple independent studies, with high precision and good age control are crucial and should be recognized as "anchor points" (e.g. Pompeii). On the other hand, the nagging problem of outliers persists. Among the possible causes are magnetic refraction, physical distortion, and inadequate chronological control. Some examples, drawn from our own investigations over the last 30 years, will be discussed in detail. These include previously unpublished data from a detailed study (more than 100 samples) of a kiln in southern Italy, and an apparently good (but aberrant) archaeodirection from a kiln in southern Spain.

  8. (Discussions of global environmental problems)

    SciTech Connect

    Krahl-Urban, B.

    1989-11-02

    The traveler visited the Oak Ridge National Laboratory (ORNL) at the request of the Environmental Sciences Division to provide programmatic interpretations and technical overviews of research topics addressing international environmental issues. Many of today's environmental problems can no longer be considered as regional-scale impacts. Global warming, acidification, ozone depletion, drought, deforestation, and air pollution effects are global-level processes that can only be effectively approached by international scientific cooperation. The traveler's recommendations for the final planning and coordination of international environmental issues emphasized focusing on international cooperation with research institutions in West Germany and in other countries of the European Community. Several key global environmental issues are addressed by the Juelich Nuclear Research Center (KFA Juelich), West Germany. Scientific cooperation with KFA Juelich should be promising in theoretical ecology, systems analysis, and toxicology. Scientific exchange between ORNL and KFA Juelich in environmental sciences has been initiated by the traveler.

  9. Telerobotics - Problems and research needs

    NASA Technical Reports Server (NTRS)

    Stark, Lawrence; Tendick, Frank; Kim, Won Soo; Anderson, Russell; Hisey, Michael

    1988-01-01

    With major emphasis on simulation, a university laboratory telerobotics facility permits problems to be approached by groups of graduate students. Helmet-mounded displays provide realism; the slaving of the display to the human operator's viewpoint gives a sense of 'telepresence' that may be useful for prolonged tasks. Using top-down three-dimensional model control of distant images allows distant images to be reduced to a few parameters to update the model used for display to the human operator in a preview mode to circumvent, in part, the communication delay. Also, the model can be used as a format for supervisory control and permit short-term local autonomous operations. Image processing algorithms can be made simpler and faster without trying to construct sensible images from the bottom. Control studies of telerobots lead to preferential manual control modes and basic paradigms for human motion and thence, perhaps, to redesign of robotic control, trajectory path planning, and rehabilitation prosthetics.

  10. The inviscid compressible Goertler problem

    NASA Technical Reports Server (NTRS)

    Dando, Andrew; Seddougui, Sharon O.

    1991-01-01

    The growth rate is studied of Goertler vortices in a compressible flow in the inviscid limit of large Goertler number. Numerical solutions are obtained for 0(1) wavenumbers. The further limits of large Mach number and large wavenumber with 0(1) Mach number are considered. It is shown that two different types of disturbance modes can appear in this problem. The first is a wall layer mode, so named as it has its eigenfunctions trapped in a thin layer away from the wall and termed a trapped layer mode for large wavenumbers and an adjustment layer mode for large Mach numbers, since then this mode has its eigenfunctions concentrated in the temperature adjustment layer. The near crossing of the modes which occurs in each of the limits mentioned is investigated.

  11. [Nutritional problems of female adolescents].

    PubMed

    Jiménez Ortega, Ana Isabel; González Iglesias, María José; Gimeno Pita, Patricia; Ortega, Rosa M

    2015-07-18

    Feeding in infancy is necessary to allow proper growth and development. Health of these early stages of life may influence the development of many diseases in the future (atherosclerosis, osteoporosis, hypertension, obesity ...). Furthermore habits set in childhood will endure throughout life. Therefore, getting adequate dietary and health patterns in childhood is vital. In adolescence occur a number of changes: rapid growth, development of secondary sexual characteristics, changes in body composition, ... that will be a challenge when getting or keeping that adequate feeding and habits. In female population requirements of different micronutrients are increased (mainly iron) and also higher energy requirement than in later stages of life occurs. However, adolescents are the main population at risk for developing eating disorders, which can pose serious problems to meet these nutritional requirements to achieve optimal development. These features and others, such as pregnant adolescents, are what make them a population that should be taken special care from nutritional point of view.

  12. Behavior problems in geriatric pets.

    PubMed

    Landsberg, Gary; Araujo, Joseph A

    2005-05-01

    Aging pets often suffer a decline in cognitive function (eg, memory,learning, perception, awareness) likely associated with age-dependent brain alterations. Clinically, cognitive dysfunction may result in various behavioral signs, including disorientation; forgetting of previously learned behaviors, such as house training; alterations in the manner in which the pet interacts with people or other pets;onset of new fears and anxiety; decreased recognition of people, places, or pets; and other signs of deteriorating memory and learning ability. Many medical problems, including other forms of brain pathologic conditions, can contribute to these signs. The practitioner must first determine the cause of the behavioral signs and then determine an appropriate course of treatment, bearing in mind the constraints of the aging process. A diagnosis of cognitive dysfunction syndrome is made once other medical and behavioral causes are ruled out.

  13. Muon problem in UHECR investigations

    NASA Astrophysics Data System (ADS)

    Petrukhin, A. A.; Bogdanov, A. G.; Kokoulin, R. P.

    2013-02-01

    In many UHECR experiments, some excess of muons is observed, which cannot be explained in frame of the existing theoretical models of hadron interaction. Attempts of its explanation through a heavy mass composition of PCR contradict the results of Xmax measurements. Really, the excess of muons appears already at lower energies (1016 - 1017 eV), but in this domain it may be explained by the trend to a heavier mass composition, which is in a qualitative agreement with the galactic model of CR origin. The absence of heavy nuclei at energies of the order of 1018 eV requires to consider other possibilities of the appearance of muon excess, including changes of hadron interaction model. The actuality of the considered problem is connected with plans of future experiments in UHECR physics, in which the necessity of its solution must be taken into account.

  14. COG validation: SINBAD Benchmark Problems

    SciTech Connect

    Lent, E M; Sale, K E; Buck, R M; Descalle, M

    2004-02-23

    We validated COG, a 3D Monte Carlo radiation transport code, against experimental data and MNCP4C simulations from the Shielding Integral Benchmark Archive Database (SINBAD) compiled by RSICC. We modeled three experiments: the Osaka Nickel and Aluminum sphere experiments conducted at the OKTAVIAN facility, and the liquid oxygen experiment conducted at the FNS facility. COG results are in good agreement with experimental data and generally within a few % of MCNP results. There are several possible sources of discrepancy between MCNP and COG results: (1) the cross-section database versions are different, MCNP uses ENDFB VI 1.1 while COG uses ENDFB VIR7, (2) the code implementations are different, and (3) the models may differ slightly. We also limited the use of variance reduction methods when running the COG version of the problems.

  15. Silicone Granulomas, a Growing Problem?

    PubMed Central

    Curreri, Alexis T.; Taylor, Gina A.; Burris, Katy

    2016-01-01

    The formation of granulomas is known to be a possible adverse effect of liquid silicone administration, used for soft tissue augmentation. Its plumping effects provide enhancement of certain body parts, such as the lips, hips, and buttocks. The desire for enhancement, perhaps influenced by popular culture and an unrealistic standard of beauty, leads individuals to seek silicone injections. There is a growing population of women and men receiving injections by unlicensed, unskilled “practitioners” not related to the healthcare profession. Complications under such circumstances are not uncommon, particularly the emergence of silicone granulomas, and the authors’ medical center has seen an increase in such cases. In this case report, the authors illustrate a young patient with significant complications from her silicone injections, review current therapies for silicone granulomas, and discuss this growing medical problem. PMID:27386046

  16. Robot computer problem solving system

    NASA Technical Reports Server (NTRS)

    Merriam, E. W.; Becker, J. D.

    1973-01-01

    A robot computer problem solving system which represents a robot exploration vehicle in a simulated Mars environment is described. The model exhibits changes and improvements made on a previously designed robot in a city environment. The Martian environment is modeled in Cartesian coordinates; objects are scattered about a plane; arbitrary restrictions on the robot's vision have been removed; and the robot's path contains arbitrary curves. New environmental features, particularly the visual occlusion of objects by other objects, were added to the model. Two different algorithms were developed for computing occlusion. Movement and vision capabilities of the robot were established in the Mars environment, using LISP/FORTRAN interface for computational efficiency. The graphical display program was redesigned to reflect the change to the Mars-like environment.

  17. The health problem of arachnidism

    PubMed Central

    Maretić, Z.; Stanić, M.

    1954-01-01

    The authors give data on arachnidism (the systemic poisoning caused by the bite of the spider Latrodectus) in general, on its distribution in the world and in Yugoslavia in particular, on the Latrodectus spider, and on the characteristic clinical syndrome of arachnidism. The bite of the Latrodectus causes great pain, disables the bitten person for a certain time, and may even cause death in a few instances. The results of the authors' own observations in the clinic and on experimental animals are given. Of all forms of therapy tried by them, the simultaneous application of calcium, antivenom, and sometimes procaine infiltration for the relief of local pains gave the best results. In view of the apparently increasing importance of arachnidism, the authors recommend the international exchange of experience on the problem. ImagesFIG. 1 PMID:14364184

  18. Outstanding problems in Mars aeronomy

    NASA Technical Reports Server (NTRS)

    Luhmann, J. G.

    1995-01-01

    Although the Phobos-2 spacecraft recently obtained important results relevant to some of the major remaining questions in Mars aeronomy, much remains to be done. In particular, not since the Viking Landers have we made in-situ measurements of aeronomical quantities such as atmospheric and ionospheric densities and temperatures below 400 km altitude. We have never made magnetic field measurements at these altitudes. Without such measurements we cannot unambiguously resolve arguments concerning issues such as the significance of the planetary magnetic field in the solar wind interaction, or understand the atmospheric cycle that leads to escape to space. With the trio of future orbiters including Mars Observer, Mars-94, and Planet-B we should see a veritable explosion of new knowledge, but some gaps in aeronomical science coverage will still remain. This paper briefly reviews some of the major unsolved problems in Mars aeronomy, and points out which are expected to remain outstanding after this flotilla of missions.

  19. The cosmological lithium problem revisited

    NASA Astrophysics Data System (ADS)

    Bertulani, C. A.; Mukhamedzhanov, A. M.; Shubhchintak

    2016-07-01

    After a brief review of the cosmological lithium problem, we report a few recent attempts to find theoretical solutions by our group at Texas A&M University (Commerce & College Station). We will discuss our studies on the theoretical description of electron screening, the possible existence of parallel universes of dark matter, and the use of non-extensive statistics during the Big Bang nucleosynthesis epoch. Last but not least, we discuss possible solutions within nuclear physics realm. The impact of recent measurements of relevant nuclear reaction cross sections for the Big Bang nucleosynthesis based on indirect methods is also assessed. Although our attempts may not able to explain the observed discrepancies between theory and observations, they suggest theoretical developments that can be useful also for stellar nucleosynthesis.

  20. The Black Hole Information Problem

    NASA Astrophysics Data System (ADS)

    Polchinski, Joseph

    The black hole information problem has been a challenge since Hawking's original 1975 paper. It led to the discovery of AdS/CFT, which gave a partial resolution of the paradox. However, recent developments, in particular the firewall puzzle, show that there is much that we do not understand. I review the black hole, Hawking radiation, and the Page curve, and the classic form of the paradox. I discuss AdS/CFT as a partial resolution. I then discuss black hole complementarity and its limitations, leading to many proposals for different kinds of `drama.' I conclude with some recent ideas. Presented at the 2014-15 Jerusalem Winter School and the 2015 TASI.

  1. Problems with drugs in Croatia.

    PubMed

    Vrhovac, B

    1997-01-01

    Croatia has 4.8 million inhabitants, 11,800 physicians, 2000 pharmacists, two now shareholding, pharmaceutical companies (about 6500 employees, total sales of about 350 million US dollars). There are a number of problems due to the war (GNP fell from 3800 to about 1500 US dollars), occupation of 25% of its territory, 0.5 million refugees and lack of resources (139 US dollars/capita for health, about 40 US dollars i.e. 30%!! for drugs)--about three times less than before the aggression. The drug situation is controlled with the help of: (1) donations (approximate value of 600 million US dollars since 1991 from Europe and US), (2) (essential) drug formularies--250 for outpatients, and 580 generic names for various levels of hospital use, (3) special efforts to purchase drugs of good quality at a reasonable price (a kind of tender), (4) control of prescribing (prescriptions, specialists referral) especially by GPs. A new Medicines Act is in preparation and about 1000 generic names are on the market. DRUG EDUCATION: Pharmaca: the Croatian journal of pharmacotherapy has been published since 1962, there are several Drug bulletins (one published since 1975); special chapters on clinical pharmacology in textbooks, translation of three editions of Laurence's textbook with special commentary and adaptation to local needs; ADR spontaneous and intensive monitoring (WHO programme) with a personal feedback to the reporters and regular articles on drug use in a number of periodicals. Data on drug consumption indicates that there is room for improvement of prescribing. There is an enthusiasm for 'vasoactive drugs'--after dipirydamole came oxpentifylline and antimicrobials are always overprescribed. All these problems will hopefully decrease when the war finally stops and when industry (especially tourism) starts being fruitful again. In any case the importance of teaching of pharmacotherapy at the under- and postgraduate level should be recognized.

  2. Inconsistent Investment and Consumption Problems

    SciTech Connect

    Kronborg, Morten Tolver; Steffensen, Mogens

    2015-06-15

    In a traditional Black–Scholes market we develop a verification theorem for a general class of investment and consumption problems where the standard dynamic programming principle does not hold. The theorem is an extension of the standard Hamilton–Jacobi–Bellman equation in the form of a system of non-linear differential equations. We derive the optimal investment and consumption strategy for a mean-variance investor without pre-commitment endowed with labor income. In the case of constant risk aversion it turns out that the optimal amount of money to invest in stocks is independent of wealth. The optimal consumption strategy is given as a deterministic bang-bang strategy. In order to have a more realistic model we allow the risk aversion to be time and state dependent. Of special interest is the case were the risk aversion is inversely proportional to present wealth plus the financial value of future labor income net of consumption. Using the verification theorem we give a detailed analysis of this problem. It turns out that the optimal amount of money to invest in stocks is given by a linear function of wealth plus the financial value of future labor income net of consumption. The optimal consumption strategy is again given as a deterministic bang-bang strategy. We also calculate, for a general time and state dependent risk aversion function, the optimal investment and consumption strategy for a mean-standard deviation investor without pre-commitment. In that case, it turns out that it is optimal to take no risk at all.

  3. Highly indefinite multigrid for eigenvalue problems

    SciTech Connect

    Borges, L.; Oliveira, S.

    1996-12-31

    Eigenvalue problems are extremely important in understanding dynamic processes such as vibrations and control systems. Large scale eigenvalue problems can be very difficult to solve, especially if a large number of eigenvalues and the corresponding eigenvectors need to be computed. For solving this problem a multigrid preconditioned algorithm is presented in {open_quotes}The Davidson Algorithm, preconditioning and misconvergence{close_quotes}. Another approach for solving eigenvalue problems is by developing efficient solutions for highly indefinite problems. In this paper we concentrate on the use of new highly indefinite multigrid algorithms for the eigenvalue problem.

  4. Individualized Math Problems in Square Root. Oregon Vo-Tech Mathematics Problem Sets.

    ERIC Educational Resources Information Center

    Cosler, Norma, Ed.

    This is one of eighteen sets of individualized mathematics problems developed by the Oregon Vo-Tech Math Project. Each of these problem packages is organized around a mathematical topic and contains problems related to diverse vocations. Solutions are provided for all problems. Problems in this volume require the computation of square roots,…

  5. Individualized Math Problems in Decimals. Oregon Vo-Tech Mathematics Problem Sets.

    ERIC Educational Resources Information Center

    Cosler, Norma, Ed.

    THis is one of eighteen sets of individualized mathematics problems developed by the Oregon Vo-Tech Math Project. Each of these problem packages is organized around a mathematical topic and contains problems related to diverse vocations. Solutions are provided for all problems. Problems in this volume concern use of decimals and are related to the…

  6. Individualized Math Problems in Trigonometry. Oregon Vo-Tech Mathematics Problem Sets.

    ERIC Educational Resources Information Center

    Cosler, Norma, Ed.

    This is one of eighteen sets of individualized mathematics problems developed by the Oregon Vo-Tech Math Project. Each of these problem packages is organized around a mathematical topic and contains problems related to diverse vocations. Solutions are provided for all problems. Problems in this volume require the use of trigonometric and inverse…

  7. Individualized Math Problems in Geometry. Oregon Vo-Tech Mathematics Problem Sets.

    ERIC Educational Resources Information Center

    Cosler, Norma, Ed.

    This is one of eighteen sets of individualized mathematics problems developed by the Oregon Vo-Tech Math Project. Each of these problem packages is organized around a mathematical topic and contains problems related to diverse vocations. Solutions are provided for all problems. The volume contains problems in applied geometry. Measurement of…

  8. Individualized Math Problems in Metrics. Oregon Vo-Tech Mathematics Problem Sets.

    ERIC Educational Resources Information Center

    Cosler, Norma, Ed.

    This is one of eighteen sets of individualized mathematics problems developed by the Oregon Vo-Tech Math Project. Each of these problem packages is organized around a mathematical topic and contains problems related to diverse vocations. Solutions are provided for all problems. This booklet contains a problem on metric measurement in the area of…

  9. Individualized Math Problems in Logarithms. Oregon Vo-Tech Mathematics Problem Sets.

    ERIC Educational Resources Information Center

    Cosler, Norma, Ed.

    THis is one of eighteen sets of individualized mathematics problems developed by the Oregon Vo-Tech Math Project. Each of these problem packages is organized around a mathematical topic and contains problems related to diverse vocations. Solutions are provided for all problems. This volume includes problems involving logarithms, exponents, and…

  10. Individualized Math Problems in Whole Numbers. Oregon Vo-Tech Mathematics Problem Sets.

    ERIC Educational Resources Information Center

    Cosler, Norma, Ed.

    This is one of eighteen sets of individualized mathematics problems developed by the Oregon Vo-Tech Math Project. Each of these problem packages is organized around a mathematical topic and contains problems related to diverse vocations. Solutions are provided for all problems. Problems in this set require computations involving whole numbers.…

  11. Individualized Math Problems in Percent. Oregon Vo-Tech Mathematics Problem Sets.

    ERIC Educational Resources Information Center

    Cosler, Norma, Ed.

    This is one of eighteen sets of individualized mathematics problems developed by the Oregon Vo-Tech Math Project. Each of these problem packages is organized around a mathematical topic and contains problems related to diverse vocations. Solutions are provided for all problems. This volume includes problems concerned with computing percents.…

  12. Individualized Math Problems in Fractions. Oregon Vo-Tech Mathematics Problem Sets.

    ERIC Educational Resources Information Center

    Cosler, Norma, Ed.

    This is one of eighteen sets of individualized mathematics problems developed by the Oregon Vo-Tech Math Project. Each of these problem packages is organized around a mathematical topic and contains problems related to diverse vocations. Solutions are provided for all problems. This package contains problems involving computation with common…

  13. Individualized Math Problems in Ratio and Proportion. Oregon Vo-Tech Mathematics Problem Sets.

    ERIC Educational Resources Information Center

    Cosler, Norma, Ed.

    This is one of eighteen sets of individualized mathematics problems developed by the Oregon Vo-Tech Math Project. Each of these problem packages is organized around a mathematical topic and contains problems related to diverse vocations. Solutions are provided for all problems. This volume contains problems involving ratio and proportion. Some…

  14. Individualized Math Problems in Simple Equations. Oregon Vo-Tech Mathematics Problem Sets.

    ERIC Educational Resources Information Center

    Cosler, Norma, Ed.

    This is one of eighteen sets of individualized mathematics problems developed by the Oregon Vo-Tech Math Project. Each of these problem packages is organized around a mathematical topic and contains problems related to diverse vocations. Solutions are provided for all problems. Problems in this volume require solution of linear equations, systems…

  15. Embedding Game-Based Problem-Solving Phase into Problem-Posing System for Mathematics Learning

    ERIC Educational Resources Information Center

    Chang, Kuo-En; Wu, Lin-Jung; Weng, Sheng-En; Sung, Yao-Ting

    2012-01-01

    A problem-posing system is developed with four phases including posing problem, planning, solving problem, and looking back, in which the "solving problem" phase is implemented by game-scenarios. The system supports elementary students in the process of problem-posing, allowing them to fully engage in mathematical activities. In total, 92 fifth…

  16. Open-Start Mathematics Problems: An Approach to Assessing Problem Solving

    ERIC Educational Resources Information Center

    Monaghan, John; Pool, Peter; Roper, Tom; Threlfall, John

    2009-01-01

    This article describes one type of mathematical problem, open-start problems, and discusses their potential for use in assessment. In open-start problems how one starts to address the problem can vary but they have a correct answer. We argue that the use of open-start problems in assessment could positively influence classroom mathematics…

  17. A Critical Investigation of the Problems with Problem-Based Learning.

    ERIC Educational Resources Information Center

    Fenwick, Tara J.; Parsons, Jim

    This paper is a critique of problem-based learning and focuses on, first, the concept of life as problem-governed and professional practice as problem-solving; and, second, the utility of problem-based learning as a pedagogical approach in pre-professional training. The paper suggests that a problem-based approach to professional education is…

  18. Quantum Algorithm for Linear Programming Problems

    NASA Astrophysics Data System (ADS)

    Joag, Pramod; Mehendale, Dhananjay

    The quantum algorithm (PRL 103, 150502, 2009) solves a system of linear equations with exponential speedup over existing classical algorithms. We show that the above algorithm can be readily adopted in the iterative algorithms for solving linear programming (LP) problems. The first iterative algorithm that we suggest for LP problem follows from duality theory. It consists of finding nonnegative solution of the equation forduality condition; forconstraints imposed by the given primal problem and for constraints imposed by its corresponding dual problem. This problem is called the problem of nonnegative least squares, or simply the NNLS problem. We use a well known method for solving the problem of NNLS due to Lawson and Hanson. This algorithm essentially consists of solving in each iterative step a new system of linear equations . The other iterative algorithms that can be used are those based on interior point methods. The same technique can be adopted for solving network flow problems as these problems can be readily formulated as LP problems. The suggested quantum algorithm cansolveLP problems and Network Flow problems of very large size involving millions of variables.

  19. Global Collaborations - Prospects and Problems

    NASA Astrophysics Data System (ADS)

    Corbett, Ian

    2005-04-01

    International collaboration has long been a feature of science. Collaborative investments in joint facilities and projects have grown considerably over the past 20-40 years, and many projects have been multinational from the start. This has been particularly true in Europe, where intergovernmental organizations such as CERN, ESA, and ESO have enabled European countries to carry out forefront science with state-of-art facilites which would have been beyond the capabilities of any one country. A brief survey of these organizations, their structure, and the possible reasons behind their success is given. The transition from regional to global creates new problems. Global scale projects face a range of generic issues which must be addressed and overcome if the project is to be a success. Each project has its own specific boundary conditions and each adopts an approach best fitted to its own objectives and constraints. Experience with billion dollar projects such as the SSC, LHC, and ITER shows the key problem areas and demonstrates the importance of preparatory work in the early stages to settle issues such as schedule, funding, location, legal and managerial structure, and oversight. A range of current and proposed intercontinental or global projects - so- called ``Megascience Projects" - is reviewed. Such projects, originally a feature of space and particle physics, are now becoming more common, and very large projects in astronomy, for example ALMA and 50 - 100m telescopes, and other areas of physics now fall into the `global' category. These projects are on such a large scale, from any scientific, managerial, financial or political perspective, and have such global importance, that they have necessarily been conceived as international from the outset. Increasing financial pressures on governments and funding agencies in the developed countries place additional demands on the project planning. The contrasting approaches, problems faced, and progress made in various

  20. Stabilization: A Descriptive Framework for Problem Solving

    NASA Astrophysics Data System (ADS)

    Savrda, Sherry L.

    2006-12-01

    An alternative description of problem solving was tested against the think-aloud protocols of twelve introductory calculus-based physics students. Think-aloud protocols are transcripts of problem-solving sessions during which participants are asked to verbalize their thoughts as they attempt to solve a problem. The stabilization model tested considers perceptions of problem difficulty to be related to four primary factors: categorization, goal interpretation, resource relevance, and complexity. A fifth superordinate factor, stabilization, considers the shifting relationships between the four primary factors over the problem-solving process. Problem solving is then described in terms of a search for a stable relationship among the four primary factors. Results from the study to be presented suggest that with further refinement, the stabilization model could be an effective alternative model of problem solving. Results related to the observed problem-solving processes undertaken by the participants will also be presented.