Topology optimization for acoustic-structure interaction problems
DEFF Research Database (Denmark)
Yoon, Gil Ho; Jensen, Jakob Søndergaard; Sigmund, Ole
2006-01-01
We propose a gradient based topology optimization algorithm for acoustic-structure (vibro-acoustic) interaction problems without an explicit interfacing boundary representation. In acoustic-structure interaction problems, the pressure field and the displacement field are governed by the Helmholtz...... to subdomain interfaces evolving during the optimization process. In this paper, we propose to use a mixed finite element formulation with displacements and pressure as primary variables (u/p formulation) which eliminates the need for explicit boundary representation. In order to describe the Helmholtz......-dimensional acoustic-structure interaction problems are optimized to show the validity of the proposed method....
DEFF Research Database (Denmark)
Yoon, Gil Ho; Jensen, Jens Stissing; Sigmund, Ole
2007-01-01
given during the optimization process. In this paper we circumvent the explicit boundary representation by using a mixed finite element formulation with displacements and pressure as primary variables (a u/p-formulation). The Helmholtz equation is obtained as a special case of the mixed formulation...... for the elastic shear modulus equating to zero. Hence, by spatial variation of the mass density, shear and bulk moduli we are able to solve the coupled problem by the mixed formulation. Using this modelling approach, the topology optimization procedure is simply implemented as a standard density approach. Several...... two-dimensional acoustic-structure problems are optimized in order to verify the proposed method....
DEFF Research Database (Denmark)
Kook, Junghwan; Jensen, Jakob Søndergaard
2014-01-01
The aim of this paper is to investigate the enhancement of the damping ratio of a structure with embedded microbeam resonators in air-filled internal cavities. In this context, we discuss theoretical aspects in the framework of the effective modal damping ratio (MDR) and derive an approximate...... relation expressing how an increased damping due to the acoustic medium surrounding the microbeam affect the MDR of the macrobeam. We further analyze the effect of including dissipation of the acoustic medium by using finite element (FE) analysis with acoustic-structure interaction (ASI) using a simple...... phenomenological acoustic loss model. An eigenvalue analysis is carried out to demonstrate the improvement of the damping characteristic of the macrobeam with the resonating microbeam in the lossy air and the results are compared to a forced vibration analysis for a macrobeam with one or multiple embedded...
Techniques to assess acoustic-structure interaction in liquid rocket engines
Davis, R. Benjamin
acoustoelastic systems. The result is the development of relatively simple techniques that allow analysts to make informed decisions concerning the importance of acoustic-structure coupling without resorting to more time consuming and complex methods. In this part, a new nondimensional parameter is derived to quantify the fundamental strength of a particular acoustic-structure interaction irrespective of material and fluid properties or cavity size. It is be shown that, in some cases, reasonable approximations of the coupled acoustic-structure frequencies can be calculated without explicit knowledge of the uncoupled component mode shapes. Monte Carlo simulations are performed to determine the parameter values over which the approximate coupled frequency expressions are accurate. General observations concerning the forced response of acoustoelastic systems are then made by investigating the response of a simplified two mode system. The third part of this research discusses the implementation of a component mode synthesis (CMS) technique for use with geometrically complex acoustoelastic systems. The feasibility of conceptually similar techniques was first demonstrated over 30 years ago. Since that time there have been remarkable advancements in computational methods. It is therefore reasonable to question the extent to which CMS remains a computationally advantageous approach for acoustoelastic systems of practical interest. This work demonstrates that relative to the most recent release of the popular finite element software package, ANSYS, CMS techniques have a significant computational advantage when the forced response of an acoustoelastic system is of interest. However, recent improvements to the unsymmetric eigensolver available in ANSYS have rendered CMS a less efficient option when calculating system frequencies and modes. The CMS technique is then used to generate new results related to geometrically complex acoustoelastic systems.
Topological Design for Acoustic-Structure Interaction Problems with a Mixed Finite Element Method
DEFF Research Database (Denmark)
Yoon, Gil Ho; Jensen, Jakob Søndergaard; Sigmund, Ole
2006-01-01
to subdomain interfaces evolving during the optimization process. In this paper, we propose to use a mixed finite element formulation with displacements and pressure as primary variables (u/p formulation) which eliminates the need for explicit boundary representation. In order to describe the Helmholtz...... equation and the linear elasticity equation, the mass density as well as the shear and bulk moduli are interpolated with the design variables. In this formulation, the coupled interface boundary conditions are automatically satisfied without having to compute surface coupling integrals. Two dimensional...
Interactive problem solving using LOGO
Boecker, Heinz-Dieter; Fischer, Gerhard
2014-01-01
This book is unique in that its stress is not on the mastery of a programming language, but on the importance and value of interactive problem solving. The authors focus on several specific interest worlds: mathematics, computer science, artificial intelligence, linguistics, and games; however, their approach can serve as a model that may be applied easily to other fields as well. Those who are interested in symbolic computing will find that Interactive Problem Solving Using LOGO provides a gentle introduction from which one may move on to other, more advanced computational frameworks or more
Current problems in the weak interactions
International Nuclear Information System (INIS)
Pais, A.
1977-01-01
Some reasons are discussed showing why the recent SU(2) x U(1) gauge theory of weak and electromagnetic interactions is not a complete theory of these interactions, Lepton theory, charm, and the CP problem are considered. 60 references
Interactive Problem-Solving Interventions
African Journals Online (AJOL)
Frew Demeke Alemu
concerted efforts of unofficial actors to establish unofficial communication ... Frew Demeke Alemu (LLB, LLM in International Human Rights Law from Lund ..... 24 Tamra Pearson d'Estrée (2009), “Problem-Solving Approaches”, (in The SAGE ...
Problem solving environment for distributed interactive applications
Rycerz, K.; Bubak, M.; Sloot, P.; Getov, V.; Gorlatch, S.; Bubak, M.; Priol, T.
2008-01-01
Interactive Problem Solving Environments (PSEs) offer an integrated approach for constructing and running complex systems, such as distributed simulation systems. To achieve efficient execution of High Level Architecture (HLA)-based distributed interactive simulations on the Grid, we introduce a PSE
Fluid Structure Interaction for Hydraulic Problems
International Nuclear Information System (INIS)
Souli, Mhamed; Aquelet, Nicolas
2011-01-01
Fluid Structure interaction plays an important role in engineering applications. Physical phenomena such as flow induced vibration in nuclear industry, fuel sloshing tank in automotive industry or rotor stator interaction in turbo machinery, can lead to structure deformation and sometimes to failure. In order to solve fluid structure interaction problems, the majority of numerical tests consists in using two different codes to separately solve pressure of the fluid and structural displacements. In this paper, a unique code with an ALE formulation approach is used to implicitly calculate the pressure of an incompressible fluid applied to the structure. The development of the ALE method as well as the coupling in a computational structural dynamic code, allows to solve more large industrial problems related to fluid structure coupling. (authors)
Ohannessian, Christine McCauley
2015-11-01
This study examined the effects of both paternal problem drinking and maternal problem drinking on adolescent internalizing problems (depression and anxiety symptomatology). Surveys were administered to 566 10th and 11th grade students from the Mid-Atlantic region of the U.S. in the spring of 2007 and again in the spring of 2008. Although significant main effects were not observed, significant interactions were found between paternal problem drinking and maternal problem drinking for internalizing problems, especially for boys. In general, these interactions indicated that when paternal problem drinking was high, depression symptomatology and anxiety symptomatology were lower if maternal problem drinking was low. Findings from this study highlight the need to consider both paternal and maternal problem drinking when examining the effects that parental problem drinking may have on adolescent adjustment. Copyright © 2015 Elsevier Ltd. All rights reserved.
PFEM application in fluid structure interaction problems
Celigueta Jordana, Miguel Ángel; Larese De Tetto, Antonia; Latorre, Salvador
2008-01-01
In the current paper the Particle Finite Element Method (PFEM), an innovative numerical method for solving a wide spectrum of problems involving the interaction of fluid and structures, is briefly presented. Many examples of the use of the PFEM with GiD support are shown. GiD framework provides a useful pre and post processor for the specific features of the method. Its advantages and shortcomings are pointed out in the present work. Peer Reviewed
Learning and interactivity in solving a transformation problem.
Guthrie, Lisa G; Vallée-Tourangeau, Frédéric; Vallée-Tourangeau, Gaëlle; Howard, Chelsea
2015-07-01
Outside the psychologist's laboratory, thinking proceeds on the basis of a great deal of interaction with artefacts that are recruited to augment problem-solving skills. The role of interactivity in problem solving was investigated using a river-crossing problem. In Experiment 1A, participants completed the same problem twice, once in a low interactivity condition, and once in a high interactivity condition (with order counterbalanced across participants). Learning, as gauged in terms of latency to completion, was much more pronounced when the high interactivity condition was experienced second. When participants first completed the task in the high interactivity condition, transfer to the low interactivity condition during the second attempt was limited; Experiment 1B replicated this pattern of results. Participants thus showed greater facility to transfer their experience of completing the problem from a low to a high interactivity condition. Experiment 2 was designed to determine the amount of learning in a low and high interactivity condition; in this experiment participants completed the problem twice, but level of interactivity was manipulated between subjects. Learning was evident in both the low and high interactivity groups, but latency per move was significantly faster in the high interactivity group, in both presentations. So-called problem isomorphs instantiated in different task ecologies draw upon different skills and abilities; a distributed cognition analysis may provide a fruitful perspective on learning and transfer.
Ecological interactions and the Netflix problem
Directory of Open Access Journals (Sweden)
Philippe Desjardins-Proulx
2017-08-01
Full Text Available Species interactions are a key component of ecosystems but we generally have an incomplete picture of who-eats-who in a given community. Different techniques have been devised to predict species interactions using theoretical models or abundances. Here, we explore the K nearest neighbour approach, with a special emphasis on recommendation, along with a supervised machine learning technique. Recommenders are algorithms developed for companies like Netflix to predict whether a customer will like a product given the preferences of similar customers. These machine learning techniques are well-suited to study binary ecological interactions since they focus on positive-only data. By removing a prey from a predator, we find that recommenders can guess the missing prey around 50% of the times on the first try, with up to 881 possibilities. Traits do not improve significantly the results for the K nearest neighbour, although a simple test with a supervised learning approach (random forests show we can predict interactions with high accuracy using only three traits per species. This result shows that binary interactions can be predicted without regard to the ecological community given only three variables: body mass and two variables for the species’ phylogeny. These techniques are complementary, as recommenders can predict interactions in the absence of traits, using only information about other species’ interactions, while supervised learning algorithms such as random forests base their predictions on traits only but do not exploit other species’ interactions. Further work should focus on developing custom similarity measures specialized for ecology to improve the KNN algorithms and using richer data to capture indirect relationships between species.
Ecological interactions and the Netflix problem.
Desjardins-Proulx, Philippe; Laigle, Idaline; Poisot, Timothée; Gravel, Dominique
2017-01-01
Species interactions are a key component of ecosystems but we generally have an incomplete picture of who-eats-who in a given community. Different techniques have been devised to predict species interactions using theoretical models or abundances. Here, we explore the K nearest neighbour approach, with a special emphasis on recommendation, along with a supervised machine learning technique. Recommenders are algorithms developed for companies like Netflix to predict whether a customer will like a product given the preferences of similar customers. These machine learning techniques are well-suited to study binary ecological interactions since they focus on positive-only data. By removing a prey from a predator, we find that recommenders can guess the missing prey around 50% of the times on the first try, with up to 881 possibilities. Traits do not improve significantly the results for the K nearest neighbour, although a simple test with a supervised learning approach (random forests) show we can predict interactions with high accuracy using only three traits per species. This result shows that binary interactions can be predicted without regard to the ecological community given only three variables: body mass and two variables for the species' phylogeny. These techniques are complementary, as recommenders can predict interactions in the absence of traits, using only information about other species' interactions, while supervised learning algorithms such as random forests base their predictions on traits only but do not exploit other species' interactions. Further work should focus on developing custom similarity measures specialized for ecology to improve the KNN algorithms and using richer data to capture indirect relationships between species.
Necklaces with interacting beads isoperimetric problem
Exner, P
2005-01-01
We discuss a pair of isoperimetric problems which at a glance seem to be unrelated. The first one is classical: one places $N$identical point charges at a closed curve $\\Gamma$ at the samearc-length distances and asks about the energy minimum, i.e. whichshape does the loop take if left by itself. The second problemcomes from quantum mechanics: we take a Schr\\"odinger operator in$L^2(\\mathbb{R}^d),\\; d=2,3,$ with $N$ identical point interactionplaced at a loop in the described way, and ask about theconfiguration which \\emph{maximizes} the ground state energy. Wereduce both of them to geometric inequalities which involve chordsof $\\Gamma$; it will be shown that a sharp local extremum is inboth cases reached by $\\Gamma$ in the form of a regular (planar)polygon and that such a $\\Gamma$ solves the two problems alsoglobally.
On some structure-turbulence interaction problems
Maekawa, S.; Lin, Y. K.
1976-01-01
The interactions between a turbulent flow structure; responding to its excitation were studied. The turbulence was typical of those associated with a boundary layer, having a cross-spectral density indicative of convection and statistical decay. A number of structural models were considered. Among the one-dimensional models were an unsupported infinite beam and a periodically supported infinite beam. The fuselage construction of an aircraft was then considered. For the two-dimensional case a simple membrane was used to illustrate the type of formulation applicable to most two-dimensional structures. Both the one-dimensional and two-dimensional structures studied were backed by a cavity filled with an initially quiescent fluid to simulate the acoustic environment when the structure forms one side of a cabin of a sea vessel or aircraft.
Ojalehto, Vesa; Podkopaev, Dmitry; Miettinen, Kaisa
2015-01-01
We generalize the applicability of interactive methods for solving computationally demanding, that is, time-consuming, multiobjective optimization problems. For this purpose we propose a new agent assisted interactive algorithm. It employs a computationally inexpensive surrogate problem and four different agents that intelligently update the surrogate based on the preferences specified by a decision maker. In this way, we decrease the waiting times imposed on the decision maker du...
Investigation of Acoustic Structure Quantification in the Diagnosis of Thyroiditis.
Park, Jisang; Hong, Hyun Sook; Kim, Chul-Hee; Lee, Eun Hye; Jeong, Sun Hye; Lee, A Leum; Lee, Heon
2016-03-01
The objective of this study was to evaluate the ability of acoustic structure quantification (ASQ) to diagnose thyroiditis. The echogenicity of 439 thyroid lobes, as determined using ASQ, was quantified and analyzed retrospectively. Thyroiditis was categorized into five subgroups. The results were presented in a modified chi-square histogram as the mode, average, ratio, blue mode, and blue average. We determined the cutoff values of ASQ from ROC analysis to detect and differentiate thyroiditis from a normal thyroid gland. We obtained data on the sensitivity and specificity of the cutoff values to distinguish between euthyroid patients with thyroiditis and patients with a normal thyroid gland. The mean ASQ values for patients with thyroiditis were statistically significantly greater than those for patients with a normal thyroid gland (p thyroiditis, the cutoff values were greater than 0.27 for the ratio, greater than 116.7 for the mean, and greater than 130.7 for the blue average. The sensitivities and specificities were as follows: 84.0% and 96.6% for the ratio, 85.3% and 83.0%, for the average, and 79.1% and 93.2% for the blue average, respectively. The ASQ parameters were successful in distinguishing patients with thyroiditis from patients with a normal thyroid gland, with likelihood ratios of 24.7 for the ratio, 5.0 for the average, and 11.6 for the blue average. With the use of the aforementioned cutoff values, the sensitivities and specificities for distinguishing between patients with thyroiditis and euthyroid patients without thyroiditis were 77.05% and 94.92% for the ratio, 85.25% and 82.20% for the average, and 77.05% and 92.37% for the blue average, respectively. ASQ can provide objective and quantitative analysis of thyroid echogenicity. ASQ parameters were successful in distinguishing between patients with thyroiditis and individuals without thyroiditis, with likelihood ratios of 24.7 for the ratio, 5.0 for the average, and 11.6 for the blue average.
Geometric Programming Approach to an Interactive Fuzzy Inventory Problem
Directory of Open Access Journals (Sweden)
Nirmal Kumar Mandal
2011-01-01
Full Text Available An interactive multiobjective fuzzy inventory problem with two resource constraints is presented in this paper. The cost parameters and index parameters, the storage space, the budgetary cost, and the objective and constraint goals are imprecise in nature. These parameters and objective goals are quantified by linear/nonlinear membership functions. A compromise solution is obtained by geometric programming method. If the decision maker is not satisfied with this result, he/she may try to update the current solution to his/her satisfactory solution. In this way we implement man-machine interactive procedure to solve the problem through geometric programming method.
Exploring classical Greek construction problems with interactive geometry software
Meskens, Ad
2017-01-01
In this book the classical Greek construction problems are explored in a didactical, enquiry based fashion using Interactive Geometry Software. The book traces the history of these problems, stating them in modern terminology. By focusing on constructions and the use of GeoGebra the reader is confronted with the same problems that ancient mathematicians once faced. The reader can step into the footsteps of Euclid, Viète and Cusanus amongst others and then by experimenting and discovering geometric relationships far exceed their accomplishments. Exploring these problems with the neusis-method lets him discover a class of interesting curves. By experimenting he will gain a deeper understanding of how mathematics is created. More than 100 exercises guide him through methods which were developed to try and solve the problems. The exercises are at the level of undergraduate students and only require knowledge of elementary Euclidean geometry and pre-calculus algebra. It is especially well-suited for those student...
Interactive Drawing Therapy and Chinese Migrants with Gambling Problems
Zhang, Wenli; Everts, Hans
2012-01-01
Ethnic Chinese migrants in a country like New Zealand face a range of well-documented challenges. A proportion of such migrants find that recreational gambling turns into a pernicious gambling problem. This issue is addressed through illustrated case studies of Interactive Drawing Therapy, a drawing-based modality of therapy that facilitates…
Problems of the π meson-nucleus interaction theory
International Nuclear Information System (INIS)
Kopaleishvili, T.I.
1984-01-01
The theory of multiple scattering as applied to PI-meson scattering on nuclei is outlined on the base of optical potential method: first in neglecting the real absorption of a pion by a nucleus and then for the case when this effect is taken into account. The pion interaction with a deuteron is considered both neglecting the pion absorption channel (the relativisitic problem of three bodies) and with account of the absorption channels and pion emission (in this case the problem is solved within the frames of the channel coupling theory for the pion-two nucleus system and the system of two nucleons). Approximate or model solutions to the problem of elastic pion-nuclear scattering primarily in the range of (3.3)-resonance are presented. The formulated theory permits to uniquely describe the observed processes caused by the strong pion interaction with a two-nucleon system
Standard problems to evaluate soil structure interaction computer codes
International Nuclear Information System (INIS)
Miller, C.A.; Costantino, C.J.; Philippacopoulos, A.J.
1979-01-01
The seismic response of nuclear power plant structures is often calculated using lumped parameter methods. A finite element model of the structure is coupled to the soil with a spring-dashpot system used to represent the interaction process. The parameters of the interaction model are based on analytic solutions to simple problems which are idealizations of the actual problems of interest. The objective of the work reported in this paper is to compare predicted responses using the standard lumped parameter models with experimental data. These comparisons are shown to be good for a fairly uniform soil system and for loadings which do not result in nonlinear interaction effects such as liftoff. 7 references, 7 figures
THE MULTIPLE CHOICE PROBLEM WITH INTERACTIONS BETWEEN CRITERIA
Directory of Open Access Journals (Sweden)
Luiz Flavio Autran Monteiro Gomes
2015-12-01
Full Text Available ABSTRACT An important problem in Multi-Criteria Decision Analysis arises when one must select at least two alternatives at the same time. This can be denoted as a multiple choice problem. In other words, instead of evaluating each of the alternatives separately, they must be combined into groups of n alternatives, where n = 2. When the multiple choice problem must be solved under multiple criteria, the result is a multi-criteria, multiple choice problem. In this paper, it is shown through examples how this problemcan be tackled on a bipolar scale. The Choquet integral is used in this paper to take care of interactions between criteria. A numerical application example is conducted using data from SEBRAE-RJ, a non-profit private organization that has the mission of promoting competitiveness, sustainable developmentand entrepreneurship in the state of Rio de Janeiro, Brazil. The paper closes with suggestions for future research.
On the strong crack-microcrack interaction problem
Gorelik, M.; Chudnovsky, A.
1992-07-01
The problem of the crack-microcrack interaction is examined with special attention given to the iterative procedure described by Chudnovsky and Kachanov (1983), Chudnovsky et al. (1984), and Horii and Nemat-Nasser (1983), which yields erroneous results as the crack tips become closer (i.e., for strong crack interaction). To understand the source of error, the traction distributions along the microcrack line on the n-th step of iteration representing the exact and asymptotic stress fields are compared. It is shown that the asymptotic solution gives a gross overestimation of the actual traction.
Electroreflectance and the problem of studying plasma-surface interactions
International Nuclear Information System (INIS)
Preppernau, B.L.
1995-01-01
A long standing problem in low-temperature plasma discharge physics is to understand in detail the mutual interaction of real exposed surfaces (electrodes) with the reactive plasma environment. In particular, one wishes to discern the influence of these surfaces on the plasma parameters given their contributions from secondary electrons and ions. This paper briefly reviews the known surface interaction processes as well as currently available diagnostics to study the interface between plasmas and surfaces. Next comes a discussion describing the application of plasma-modulated electroreflectance to this research and some potential experimental techniques
Two-body problem for Weber-like interactions
International Nuclear Information System (INIS)
Clemente, R.A.; Assis, A.K.T.
1991-01-01
The problem of two moving bodies interacting through a Weber-like force is presented. Trajectories are obtained analytically once relativistic and quantic considerations are neglected. The main results are that in the case of limited trajectories, in general, they are not closed and in the case of open trajectories, the deflection angles are not the same for similar particles with given energies and angular momenta but opposite potentials. This last feature suggests the possibility of a direct verification of the validity of Weber's law of force for electromagnetic interactions
Topology optimization of fluid-structure-interaction problems in poroelasticity
DEFF Research Database (Denmark)
Andreasen, Casper Schousboe; Sigmund, Ole
2013-01-01
This paper presents a method for applying topology optimization to fluid-structure interaction problems in saturated poroelastic media. The method relies on a multiple-scale method applied to periodic media. The resulting model couples the Stokes flow in the pores of the structure with the deform...... by topology optimization in order to optimize the performance of a shock absorber and test the pressure loading capabilities and optimization of an internally pressurized lid. © 2013 Published by Elsevier B.V....
Exacerbating the Cosmological Constant Problem with Interacting Dark Energy Models.
Marsh, M C David
2017-01-06
Future cosmological surveys will probe the expansion history of the Universe and constrain phenomenological models of dark energy. Such models do not address the fine-tuning problem of the vacuum energy, i.e., the cosmological constant problem (CCP), but can make it spectacularly worse. We show that this is the case for "interacting dark energy" models in which the masses of the dark matter states depend on the dark energy sector. If realized in nature, these models have far-reaching implications for proposed solutions to the CCP that require the number of vacua to exceed the fine-tuning of the vacuum energy density. We show that current estimates of the number of flux vacua in string theory, N_{vac}∼O(10^{272 000}), are far too small to realize certain simple models of interacting dark energy and solve the cosmological constant problem anthropically. These models admit distinctive observational signatures that can be targeted by future gamma-ray observatories, hence making it possible to observationally rule out the anthropic solution to the cosmological constant problem in theories with a finite number of vacua.
Problems in the links between scattering data and interaction potentials
International Nuclear Information System (INIS)
Amos, K.
1995-01-01
The scattering function is of paramount importance in any approaches by which quantitative information on the interaction between colliding quantal systems of nuclear, atomic or molecular type, may be sought from measured, elastic scattering data. Therein there are two possible spectral parameters, the energy and the angular momentum. Most experimental results suggest use of fixed energy and variable angular momentum schemes. Such fixed energy data and their analyses are the subject of this report, with particular emphasis placed upon the problems of the link between data and the scattering function. 18 figs
Problems in the links between scattering data and interaction potentials
Energy Technology Data Exchange (ETDEWEB)
Amos, K.
1995-10-01
The scattering function is of paramount importance in any approaches by which quantitative information on the interaction between colliding quantal systems of nuclear, atomic or molecular type, may be sought from measured, elastic scattering data. Therein there are two possible spectral parameters, the energy and the angular momentum. Most experimental results suggest use of fixed energy and variable angular momentum schemes. Such fixed energy data and their analyses are the subject of this report, with particular emphasis placed upon the problems of the link between data and the scattering function. 18 figs.
Visualization of protein interaction networks: problems and solutions
Directory of Open Access Journals (Sweden)
Agapito Giuseppe
2013-01-01
Full Text Available Abstract Background Visualization concerns the representation of data visually and is an important task in scientific research. Protein-protein interactions (PPI are discovered using either wet lab techniques, such mass spectrometry, or in silico predictions tools, resulting in large collections of interactions stored in specialized databases. The set of all interactions of an organism forms a protein-protein interaction network (PIN and is an important tool for studying the behaviour of the cell machinery. Since graphic representation of PINs may highlight important substructures, e.g. protein complexes, visualization is more and more used to study the underlying graph structure of PINs. Although graphs are well known data structures, there are different open problems regarding PINs visualization: the high number of nodes and connections, the heterogeneity of nodes (proteins and edges (interactions, the possibility to annotate proteins and interactions with biological information extracted by ontologies (e.g. Gene Ontology that enriches the PINs with semantic information, but complicates their visualization. Methods In these last years many software tools for the visualization of PINs have been developed. Initially thought for visualization only, some of them have been successively enriched with new functions for PPI data management and PIN analysis. The paper analyzes the main software tools for PINs visualization considering four main criteria: (i technology, i.e. availability/license of the software and supported OS (Operating System platforms; (ii interoperability, i.e. ability to import/export networks in various formats, ability to export data in a graphic format, extensibility of the system, e.g. through plug-ins; (iii visualization, i.e. supported layout and rendering algorithms and availability of parallel implementation; (iv analysis, i.e. availability of network analysis functions, such as clustering or mining of the graph, and the
Nuclear many-body problem with repulsive hard core interactions
Energy Technology Data Exchange (ETDEWEB)
Haddad, L M
1965-07-01
The nuclear many-body problem is considered using the perturbation-theoretic approach of Brueckner and collaborators. This approach is outlined with particular attention paid to the graphical representation of the terms in the perturbation expansion. The problem is transformed to centre-of-mass coordinates in configuration space and difficulties involved in ordinary methods of solution of the resulting equation are discussed. A new technique, the 'reference spectrum method', devised by Bethe, Brandow and Petschek in an attempt to simplify the numerical work in presented. The basic equations are derived in this approximation and considering the repulsive hard core part of the interaction only, the effective mass is calculated at high momentum (using the same energy spectrum for both 'particle' and 'hole' states). The result of 0.87m is in agreement with that of Bethe et al. A more complete treatment using the reference spectrum method in introduced and a self-consistent set of equations is established for the reference spectrum parameters again for the case of hard core repulsions. (author)
Halim, Dunant; Cheng, Li; Su, Zhongqing
2011-03-01
The work was aimed to develop a robust virtual sensing design methodology for sensing and active control applications of vibro-acoustic systems. The proposed virtual sensor was designed to estimate a broadband acoustic interior sound pressure using structural sensors, with robustness against certain dynamic uncertainties occurring in an acoustic-structural coupled enclosure. A convex combination of Kalman sub-filters was used during the design, accommodating different sets of perturbed dynamic model of the vibro-acoustic enclosure. A minimax optimization problem was set up to determine an optimal convex combination of Kalman sub-filters, ensuring an optimal worst-case virtual sensing performance. The virtual sensing and active noise control performance was numerically investigated on a rectangular panel-cavity system. It was demonstrated that the proposed virtual sensor could accurately estimate the interior sound pressure, particularly the one dominated by cavity-controlled modes, by using a structural sensor. With such a virtual sensing technique, effective active noise control performance was also obtained even for the worst-case dynamics. © 2011 Acoustical Society of America
Interactive operational decision making : Purchasing situations & mutual liability problems
Groote Schaarsberg, M.
2014-01-01
Three chapters of this dissertation deal with three different types of interactive purchasing situations, in which multiple buying organizations interact with similar (or possibly the same) suppliers for the procurement of the same commodity. Decisions to be made in interactive purchasing concern if
Structural priority approach to fluid-structure interaction problems
International Nuclear Information System (INIS)
Au-Yang, M.K.; Galford, J.E.
1981-01-01
In a large class of dynamic problems occurring in nuclear reactor safety analysis, the forcing function is derived from the fluid enclosed within the structure itself. Since the structural displacement depends on the fluid pressure, which in turn depends on the structural boundaries, a rigorous approach to this class of problems involves simultaneous solution of the coupled fluid mechanics and structural dynamics equations with the structural response and the fluid pressure as unknowns. This paper offers an alternate approach to the foregoing problems. 8 refs
Solutions to the Problem of Diminished Social Interaction
Peter K. Jonason; Gregory D. Webster; A. Elizabeth Lindsey
2008-01-01
Social animals, like humans, need to interact with others, but this is not always possible. When genuine social interaction is lacking, individuals may seek out or use sources of interaction that co-opt agency detection mechanisms vis-à-vis the human voice and images of people, called social snacking. Study 1 (N = 240) found that ratings of how alone participants felt were correlated with frequency of talking to themselves and using the TV for company. Study 2 (N = 66) was a daily diary study...
Seal, Kala Chand; Przasnyski, Zbigniew H.; Leon, Linda A.
2010-01-01
Do students learn to model OR/MS problems better by using computer-based interactive tutorials and, if so, does increased interactivity in the tutorials lead to better learning? In order to determine the effect of different levels of interactivity on student learning, we used screen capture technology to design interactive support materials for…
Albert Einstein and the problem of unification of fundamental interactions
International Nuclear Information System (INIS)
Arodz, H.
1986-01-01
Albert Einstein's attempts to construct a unified field theory of electromagnetic and gravitational interactions are presented and commented from the standpoint of the present day physics. 16 refs. (author)
Interaction range perturbation theory for three-particle problem
International Nuclear Information System (INIS)
Simenog, I.V.; Shapoval, D.V.
1988-01-01
The limit of zero interaction range is correctly defined for a system of three spinless particles and three particles in a doublet state. The scattering amplitude is expanded with respect to the interaction range r, and the corrections of order r ln r, r, and r 2 ln2 r are found. An explicit model-independent asymptotic expression is obtained for the scattering amplitude in terms of the scattering length, and its accuracy is established
Molenaar, Dylan; Middeldorp, Christel; van Beijsterveldt, Toos; Boomsma, Dorret I
2015-01-01
This study tested for Genotype × Environment (G × E) interaction on behavioral and emotional problems in children using new methods that do not require identification of candidate genes or environments, can distinguish between interaction with shared and unique environment, and are insensitive to scale effects. Parental ratings of problem behavior from 14,755 twin pairs (5.3 years, SD = 0.22) indicated G × E interaction on emotional liability, social isolation, aggression, attention problems, dependency, anxiety, and physical coordination. Environmental influences increased in children who were genetically more predisposed to problem behavior, with ~20% of the variance due to G × E interaction (8% for anxiety to 37% for attention problems). Ignoring G × E interaction does not greatly bias heritability estimates, but it does offer a comprehensive model of the etiology for childhood problems. © 2015 The Authors. Child Development © 2015 Society for Research in Child Development, Inc.
Two-center Coulomb problem with Calogero interaction
Energy Technology Data Exchange (ETDEWEB)
Hakobyan, T., E-mail: tigran.hakobyan@ysu.am; Nersessian, A., E-mail: arnerses@ysu.am [Armenia Tomsk Polytechnic University, Yerevan State University (Russian Federation)
2017-03-15
We show that the Calogero-type perturbation preserves the integrability and partial separation of variables for the Stark–Coulomb and two-center Coulomb problems, and present the explicit expressions of their constants of motion. We reveal that this perturbation preserves the spectra of initial systems, but leads to the change of degree of degeneracy.
Rhee, Sun Jung; Hong, Hyun Sook; Kim, Chul-Hee; Lee, Eun Hye; Cha, Jang Gyu; Jeong, Sun Hye
2015-12-01
This study aimed to evaluate the usefulness of Acoustic Structure Quantification (ASQ; Toshiba Medical Systems Corporation, Nasushiobara, Japan) values in the diagnosis of Hashimoto thyroiditis using B-mode sonography and to identify a cutoff ASQ level that differentiates Hashimoto thyroiditis from normal thyroid tissue. A total of 186 thyroid lobes with Hashimoto thyroiditis and normal thyroid glands underwent sonography with ASQ imaging. The quantitative results were reported in an echo amplitude analysis (Cm(2)) histogram with average, mode, ratio, standard deviation, blue mode, and blue average values. Receiver operating characteristic curve analysis was performed to assess the diagnostic ability of the ASQ values in differentiating Hashimoto thyroiditis from normal thyroid tissue. Intraclass correlation coefficients of the ASQ values were obtained between 2 observers. Of the 186 thyroid lobes, 103 (55%) had Hashimoto thyroiditis, and 83 (45%) were normal. There was a significant difference between the ASQ values of Hashimoto thyroiditis glands and those of normal glands (P thyroiditis were significantly greater than those in patients with normal thyroid glands. The areas under the receiver operating characteristic curves for the ratio, blue average, average, blue mode, mode, and standard deviation were: 0.936, 0.902, 0.893, 0.855, 0.846, and 0.842, respectively. The ratio cutoff value of 0.27 offered the best diagnostic performance, with sensitivity of 87.38% and specificity of 95.18%. The intraclass correlation coefficients ranged from 0.86 to 0.94, which indicated substantial agreement between the observers. Acoustic Structure Quantification is a useful and promising sonographic method for diagnosing Hashimoto thyroiditis. Not only could it be a helpful tool for quantifying thyroid echogenicity, but it also would be useful for diagnosis of Hashimoto thyroiditis. © 2015 by the American Institute of Ultrasound in Medicine.
Use of Lanczos vectors in fluid/structure interaction problems
International Nuclear Information System (INIS)
Jeans, R.; Mathews, I.C.
1992-01-01
The goals of any numerical computational technique used for the solution of structural acoustics problems in the exterior infinite domain should be of accuracy with rapid convergence, robustness, and computational efficiency. A computer program has been developed to achieve each of these three goals. Accuracy and robustness in the numerical representation of the integral equations used to represent the infinite fluid was attained through the use of boundary element implementations of the surface Helmholtz integral equations. The computational efficiency was resolved through the use of Lanczos vectors to model the deformation characteristics of the structure. The authors have developed collocation and variational techniques to overcome the difficulties previously encountered in the numerical implementation of the hypersingular integral operator. The Cauchy singularity present in the integral formulation is made numerically amenable through the use of tangential derivatives in both the collocation and variational techniques. The variational approach has the advantage that the resulting added fluid mass term is symmetric and combines efficiently with a finite element approximation of the structural elastic response. Several different strategies making use of the Lanczos vectors have been investigated. The first involved the use of Lanczos vectors solely to characterize the structural response. This reduced form of the structural dynamical matrix was then substituted back into a Burton and Miller formulation of the acoustic problem. The second strategy investigated involved forming the complex Lanzcos vectors of the dynamical matrix formed from the addition of a symmetrical added fluid matrix to the structural mass matrix. The size of resultant matrix equation set solved at each frequency for this strategy is determined by the number of Lanczos vectors used. 19 refs., 10 figs., 2 tabs
Directory of Open Access Journals (Sweden)
M.S. Osman
2018-03-01
Full Text Available In this paper, an interactive approach for solving multi-level multi-objective fractional programming (ML-MOFP problems with fuzzy parameters is presented. The proposed interactive approach makes an extended work of Shi and Xia (1997. In the first phase, the numerical crisp model of the ML-MOFP problem has been developed at a confidence level without changing the fuzzy gist of the problem. Then, the linear model for the ML-MOFP problem is formulated. In the second phase, the interactive approach simplifies the linear multi-level multi-objective model by converting it into separate multi-objective programming problems. Also, each separate multi-objective programming problem of the linear model is solved by the ∊-constraint method and the concept of satisfactoriness. Finally, illustrative examples and comparisons with the previous approaches are utilized to evince the feasibility of the proposed approach.
Vorotnikov, K.; Starosvetsky, Y.
2018-01-01
The present study concerns two-dimensional nonlinear mechanisms of bidirectional and unidirectional channeling of longitudinal and shear waves emerging in the locally resonant acoustic structure. The system under consideration comprises an oscillatory chain of the axially coupled masses. Each mass of the chain is subject to the local linear potential along the lateral direction and incorporates the lightweight internal rotator. In the present work, we demonstrate the emergence of special resonant regimes of complete bi- and unidirectional transitions between the longitudinal and the shear waves of the locally resonant chain. These regimes are manifested by the two-dimensional energy channeling between the longitudinal and the shear traveling waves in the recurrent as well as the irreversible fashion. We show that the spatial control of the two dimensional energy flow between the longitudinal and the shear waves is solely governed by the motion of the internal rotators. Nonlinear analysis of the regimes of a bidirectional wave channeling unveils their global bifurcation structure and predicts the zones of their spontaneous transitions from a complete bi-directional wave channeling to the one-directional entrapment. An additional regime of a complete irreversible resonant transformation of the longitudinal wave into a shear wave is analyzed in the study. The intrinsic mechanism governing the unidirectional wave reorientation is described analytically. The results of the analysis of both mechanisms are substantiated by the numerical simulations of the full model and are found to be in a good agreement.
Information content and acoustic structure of male African elephant social rumbles.
Stoeger, Angela S; Baotic, Anton
2016-06-08
Until recently, the prevailing theory about male African elephants (Loxodonta africana) was that, once adult and sexually mature, males are solitary and targeted only at finding estrous females. While this is true during the state of 'musth' (a condition characterized by aggressive behavior and elevated androgen levels), 'non-musth' males exhibit a social system seemingly based on companionship, dominance and established hierarchies. Research on elephant vocal communication has so far focused on females, and very little is known about the acoustic structure and the information content of male vocalizations. Using the source and filter theory approach, we analyzed social rumbles of 10 male African elephants. Our results reveal that male rumbles encode information about individuality and maturity (age and size), with formant frequencies and absolute fundamental frequency values having the most informative power. This first comprehensive study on male elephant vocalizations gives important indications on their potential functional relevance for male-male and male-female communication. Our results suggest that, similar to the highly social females, future research on male elephant vocal behavior will reveal a complex communication system in which social knowledge, companionship, hierarchy, reproductive competition and the need to communicate over long distances play key roles.
Huang, Yang; Liu, Guang-Jian; Liao, Bing; Huang, Guang-Liang; Liang, Jin-Yu; Zhou, Lu-Yao; Wang, Fen; Li, Wei; Xie, Xiao-Yan; Wang, Wei; Lu, Ming-De
2015-09-01
The aims of the present study are to assess the impact factors on acoustic structure quantification (ASQ) ultrasound and find the optimal parameter for the assessment of liver fibrosis. Twenty healthy volunteers underwent ASQ examinations to evaluate impact factors in ASQ image acquisition and analysis. An additional 113 patients with liver diseases underwent standardized ASQ examinations, and the results were compared with histologic staging of liver fibrosis. We found that the right liver displayed lower values of ASQ parameters than the left (p = 0.000-0.021). Receive gain experienced no significant impact except gain 70 (p = 0.193-1.000). With regard to different diameter of involved vessels in regions of interest, the group ≤2.0 mm differed significantly with the group 2.1-5.0 mm (p = 0.000-0.033) and the group >5.0 mm (p = 0.000-0.062). However, the region of interest size (p = 0.438-1.000) and depth (p = 0.072-0.764) had no statistical impact. Good intra- and inter-operator reproducibilities were found in both image acquisitions and offline image analyses. In the liver fibrosis study, the focal disturbance ratio had the highest correlation with histologic fibrosis stage (r = 0.67, p the assessment of liver fibrosis. Copyright © 2015 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.
Lee, Chwee Beng
2010-01-01
This study examines the interactions between problem solving and conceptual change in an elementary science class where students build system dynamic models as a form of problem representations. Through mostly qualitative findings, we illustrate the interplay of three emerging intervening conditions (epistemological belief, structural knowledge…
Berge, Maria; Danielsson, Anna T.
2013-01-01
The purpose of this article is to explore how a group of four university physics students addressed mechanics problems, in terms of student direction of attention, problem solving strategies and their establishment of and ways of interacting. Adapted from positioning theory, the concepts "positioning" and "storyline" are used to describe and to…
Ceberio, Mikel; Almudí, José Manuel; Franco, Ángel
2016-01-01
In recent years, interactive computer simulations have been progressively integrated in the teaching of the sciences and have contributed significant improvements in the teaching-learning process. Practicing problem-solving is a key factor in science and engineering education. The aim of this study was to design simulation-based problem-solving…
Molenaar, D.; Middeldorp, C.; van Beijsterveldt, T.; Boomsma, D.I.
2015-01-01
This study tested for Genotype × Environment (G × E) interaction on behavioral and emotional problems in children using new methods that do not require identification of candidate genes or environments, can distinguish between interaction with shared and unique environment, and are insensitive to
Vendlinski, Matthew K.; Lemery-Chalfant, Kathryn; Essex, Marilyn J.; Goldsmith, H. Hill
2011-01-01
Background: Identifying how genetic risk interacts with experience to predict psychopathology is an important step toward understanding the etiology of mental health problems. Few studies have examined genetic risk by experience interaction (GxE) in the development of childhood psychopathology. Methods: We used both co-twin and parent mental…
Tee, Abi; Reed, Phil
2017-01-01
Pupils with autism spectrum disorder (ASD) received 6 months of intensive interaction or treatment as usual. They were assessed for behaviour problems at the start and end of the period, and changes were related to child and parent factors. Intensive interaction did not offer any greater advantages to child behaviour than treatment as usual.…
Molenaar, D.; Middeldorp, C.M.; van Beijsterveldt, C.E.M.; Boomsma, D.I.
2015-01-01
This study tested for Genotype × Environment (G × E) interaction on behavioral and emotional problems in children using new methods that do not require identification of candidate genes or environments, can distinguish between interaction with shared and unique environment, and are insensitive to
Interacting dark sector and the coincidence problem within the scope of LRS Bianchi type I model
Muharlyamov, Ruslan K.; Pankratyeva, Tatiana N.
2018-05-01
It is shown that a suitable interaction between dark energy and dark matter in locally rotationally symmetric (LRS) Bianchi-I space-time can solve the coincidence problem and not contradict the accelerated expansion of present Universe. The interaction parameters are estimated from observational data.
Hartley, Sigan L.; Papp, Lauren M.; Blumenstock, Shari; Floyd, Frank; Goetz, Greta L.
2016-01-01
The vulnerability-stress-adaptation model guided this examination of the impact of daily fluctuations in the symptoms and co-occurring behavior problems of children with autism spectrum disorder (ASD) on parents’ couple problem-solving interactions in natural settings and as these interactions spontaneously occur. A 14-day daily diary was completed by mothers and fathers in 176 families who had a child with ASD. On each day of the diary, parents separately reported on the child with ASD's daily level of symptoms and co-occurring behavior problems and the topic and level of negative affect in their most meaningful or important daily couple problem-solving interaction. Multilevel modeling was used to account for the within-person, within-couple nested structure of the data. Results indicated that many parents are resilient to experiencing a day with a high level of child ASD symptoms and co-occurring behavior problems and do not report more negative couple problem-solving interactions. However, household income, level of parental broader autism phenotype, and presence of multiple children with special care needs served as vulnerability factors in that they were related to a higher overall rating of negative affect in couple interactions and moderated the impact of reporting a day with a high level of child ASD symptoms and co-occurring behavior problems on next-day ratings of negative couple problem-solving interactions. The magnitude of these effects was small. Understanding mechanisms that support adaptive couple interactions in parents of children with ASD is critical for promoting best outcomes. PMID:27336179
De Kruijf, J.
2007-01-01
Water management issues are often complex, unstructured problems. They are complex, because they are part of a natural and human system wich consists of many diverse, interdependent elements, e.g. upstream events influence the water system downstream, different interdependent goverment layers,
A Boundary Element Solution to the Problem of Interacting AC Fields in Parallel Conductors
Directory of Open Access Journals (Sweden)
Einar M. Rønquist
1984-04-01
Full Text Available The ac fields in electrically insulated conductors will interact through the surrounding electromagnetic fields. The pertinent field equations reduce to the Helmholtz equation inside each conductor (interior problem, and to the Laplace equation outside the conductors (exterior problem. These equations are transformed to integral equations, with the magnetic vector potential and its normal derivative on the boundaries as unknowns. The integral equations are then approximated by sets of algebraic equations. The interior problem involves only unknowns on the boundary of each conductor, while the exterior problem couples unknowns from several conductors. The interior and the exterior problem are coupled through the field continuity conditions. The full set of equations is solved by standard Gaussian elimination. We also show how the total current and the dissipated power within each conductor can be expressed as boundary integrals. Finally, computational results for a sample problem are compared with a finite difference solution.
Directory of Open Access Journals (Sweden)
A. S. Koval
2010-01-01
Full Text Available The paper considers problems concerning electromechanical interaction in elevators with an adjustable asynchronous electric drive equipped with the vector control systems under direct torque control and direct torque control with pulse-width modulator. A mathematical description of electromechanical elevator system with due account of nonlinearity of the worm gear is given in the paper. The paper presents a simplified circuit design of a control system with a fuzzy speed controller. It has been established that the factor of electromechanical interaction in electromechanical system with the adjustable asynchronous electric drive and an fuzzy speed controller is within the range which corresponds to existence of the essential electromechanical interaction.
[Theraplay--interactive therapy between parent and child in juvenile mental problems].
Mäkelä, Jukka; Salo, Saara
2011-01-01
Parent-child interaction therapy is an effective means to prevent and correct children's mental problems. Interactive interventions shown to be effective share common features: the focus is on the support of the parent's sensitivity, positive guiding ability and reflective capability. Simultaneous participation of both parents in the therapy, application of video observation and affirmation of positive collaborative relationship with the parents seem to increase the efficacy of the intervention. The above-mentioned elements are utilized in an interactive therapy method called Theraplay.
Singh, Chandralekha
2016-01-01
We discuss the development of interactive video tutorial-based problems to help introductory physics students learn effective problem solving heuristics. The video tutorials present problem solving strategies using concrete examples in an interactive environment. They force students to follow a systematic approach to problem solving and students are required to solve sub-problems (research-guided multiple choice questions) to show their level of understanding at every stage of prob lem solvin...
Endendijk, J. J.; de Bruijn, A.; van Bakel, H.J.A.; Wijnen, H.; Pop, V.J.M.; van Baar, A.L.
2017-01-01
The role of mother-infant interaction quality is studied in the relation between prenatal maternal emotional symptoms and child behavioral problems. Healthy pregnant, Dutch women (N = 96, M = 31.6, SD = 3.3) were allocated to the "exposed group" (n = 46), consisting of mothers with high levels of
Preschool Interactive Peer Play Mediates Problem Behavior and Learning for Low-Income Children
Bulotsky-Shearer, Rebecca J.; Bell, Elizabeth R.; Romero, Sandy L.; Carter, Tracy M.
2012-01-01
The study employed a developmental, ecological, and resiliency framework to examine whether interactive peer play competencies mediated associations between teacher reported problem behavior and learning outcomes for a representative sample of urban low-income children (N = 507 across 46 Head Start classrooms). Structural equation models provided…
A Quintessence Problem in Self-interacting Brans-Dicke Theory
Chakraborty, Subenoy; Chakraborty, N. C.; Debnath, Ujjal
2003-01-01
A quintessence scalar field in self-interacting Brans-Dicke theory is shown to give rise to a non-decelerated expansion of the present universe for open, flat and closed models. Along with providing a non-decelerating solution, it can potentially solve the flatness problem too.
Schmidt, Jonathan D.; Bednar, Mary K.; Willse, Lena V.; Goetzel, Amanda L.; Concepcion, Anthony; Pincus, Shari M.; Hardesty, Samantha L.; Bowman, Lynn G.
2017-01-01
A primary goal of behavioral interventions is to reduce dangerous or inappropriate behavior and to generalize treatment effects across various settings. However, there is a lack of research evaluating generalization of treatment effects while individuals with functionally equivalent problem behavior interact with each other. For the current study,…
Radiation interaction with substance and simulation of the nuclear geophysical problems
International Nuclear Information System (INIS)
Pshenichnyj, G.A.
1982-01-01
Main processes of interaction of various types of nuclear radiation (NR) with substance, NR transport theory and physical- mathematical simulation of basic problems of nuclear geophysics (NG) are considered. General classification of NG methods according to the type of the detected radiation with a more detailed division according to the physical essence of the interaction process employed is given. Direct NG problems are related to the study of space- energy radiation distribution in substance under certain cross sections of elementary interaction processes, substance properties and specified geometric conditions. The theoretical solution of the direct problems is based on using mathematical models of radiation transport in specified media. The NG inverse problems consist in determining element composition and other medium properties by data of integral or spectral characteristics of NR fields measurements. The NR in the course of its transport in substance can experience dozens of elementary interaction processes, the predominance of this or that process depending on NR energy, medium properties and geometric measurement conditions. This explains a wide NG method diversity. The Monte Carlo method application in the NR transport theory and various methods of decreasing calculations labour input are considered [ru
EZLP: An Interactive Computer Program for Solving Linear Programming Problems. Final Report.
Jarvis, John J.; And Others
Designed for student use in solving linear programming problems, the interactive computer program described (EZLP) permits the student to input the linear programming model in exactly the same manner in which it would be written on paper. This report includes a brief review of the development of EZLP; narrative descriptions of program features,…
An interactive problem-solving approach to teach traumatology for medical students.
Abu-Zidan, Fikri M; Elzubeir, Margaret A
2010-08-13
We aimed to evaluate an interactive problem-solving approach for teaching traumatology from perspectives of students and consider its implications on Faculty development. A two hour problem-solving, interactive tutorial on traumatology was structured to cover main topics in trauma management. The tutorial was based on real cases covering specific topics and objectives. Seven tutorials (5-9 students in each) were given by the same tutor with the same format for fourth and fifth year medical students in Auckland and UAE Universities (n = 50). A 16 item questionnaire, on a 7 point Likert-type scale, focusing on educational tools, tutor-based skills, and student-centered skills were answered by the students followed by open ended comments. The tutorials were highly ranked by the students. The mean values of educational tools was the highest followed by tutor-centered skills and finally student-centered skills. There was a significant increase of the rating of studied attributes over time (F = 3.9, p = 0.004, ANOVA). Students' open ended comments were highly supportive of the interactive problem-solving approach for teaching traumatology. The interactive problem-solving approach for tutorials can be an effective enjoyable alternative or supplement to traditional instruction for teaching traumatology to medical students. Training for this approach should be encouraged for Faculty development.
Zhao, Z.; van Albada, G.D.; Tirado-Ramos, A.; Zajac, K.; Sloot, P.M.A.
2003-01-01
In Problem Solving Environments (PSE), Interactive Simulation Systems (ISS) are an important interactive mode for studying complex scientific problems. But efficient and user-friendly tools for designing interactive experiments lack in many PSEs. Mechanisms, such as data flow and control flow
Directory of Open Access Journals (Sweden)
Mark A. McDaniel
2016-11-01
Full Text Available The existing literature indicates that interactive-engagement (IE based general physics classes improve conceptual learning relative to more traditional lecture-oriented classrooms. Very little research, however, has examined quantitative problem-solving outcomes from IE based relative to traditional lecture-based physics classes. The present study included both pre- and post-course conceptual-learning assessments and a new quantitative physics problem-solving assessment that included three representative conservation of energy problems from a first-semester calculus-based college physics course. Scores for problem translation, plan coherence, solution execution, and evaluation of solution plausibility were extracted for each problem. Over 450 students in three IE-based sections and two traditional lecture sections taught at the same university during the same semester participated. As expected, the IE-based course produced more robust gains on a Force Concept Inventory than did the lecture course. By contrast, when the full sample was considered, gains in quantitative problem solving were significantly greater for lecture than IE-based physics; when students were matched on pre-test scores, there was still no advantage for IE-based physics on gains in quantitative problem solving. Further, the association between performance on the concept inventory and quantitative problem solving was minimal. These results highlight that improved conceptual understanding does not necessarily support improved quantitative physics problem solving, and that the instructional method appears to have less bearing on gains in quantitative problem solving than does the kinds of problems emphasized in the courses and homework and the overlap of these problems to those on the assessment.
Childhood problem behavior and parental divorce: evidence for gene-environment interaction.
Robbers, Sylvana; van Oort, Floor; Huizink, Anja; Verhulst, Frank; van Beijsterveldt, Catharina; Boomsma, Dorret; Bartels, Meike
2012-10-01
The importance of genetic and environmental influences on children's behavioral and emotional problems may vary as a function of environmental exposure. We previously reported that 12-year-olds with divorced parents showed more internalizing and externalizing problems than children with married parents, and that externalizing problems in girls precede and predict later parental divorce. The aim of the current study was to investigate as to whether genetic and environmental influences on internalizing and externalizing problems were different for children from divorced versus non-divorced families. Maternal ratings on internalizing and externalizing problems were collected with the Child Behavior Checklist in 4,592 twin pairs at ages 3 and 12 years, of whom 367 pairs had experienced a parental divorce between these ages. Variance in internalizing and externalizing problems at ages 3 and 12 was analyzed with biometric models in which additive genetic and environmental effects were allowed to depend on parental divorce and sex. A difference in the contribution of genetic and environmental influences between divorced and non-divorced groups would constitute evidence for gene-environment interaction. For both pre- and post-divorce internalizing and externalizing problems, the total variances were larger for children from divorced families, which was mainly due to higher environmental variances. As a consequence, heritabilities were lower for children from divorced families, and the relative contributions of environmental influences were higher. Environmental influences become more important in explaining variation in children's problem behaviors in the context of parental divorce.
Reformulation of the covering and quantizer problems as ground states of interacting particles
Torquato, S.
2010-11-01
It is known that the sphere-packing problem and the number-variance problem (closely related to an optimization problem in number theory) can be posed as energy minimizations associated with an infinite number of point particles in d -dimensional Euclidean space Rd interacting via certain repulsive pair potentials. We reformulate the covering and quantizer problems as the determination of the ground states of interacting particles in Rd that generally involve single-body, two-body, three-body, and higher-body interactions. This is done by linking the covering and quantizer problems to certain optimization problems involving the “void” nearest-neighbor functions that arise in the theory of random media and statistical mechanics. These reformulations, which again exemplify the deep interplay between geometry and physics, allow one now to employ theoretical and numerical optimization techniques to analyze and solve these energy minimization problems. The covering and quantizer problems have relevance in numerous applications, including wireless communication network layouts, the search of high-dimensional data parameter spaces, stereotactic radiation therapy, data compression, digital communications, meshing of space for numerical analysis, and coding and cryptography, among other examples. In the first three space dimensions, the best known solutions of the sphere-packing and number-variance problems (or their “dual” solutions) are directly related to those of the covering and quantizer problems, but such relationships may or may not exist for d≥4 , depending on the peculiarities of the dimensions involved. Our reformulation sheds light on the reasons for these similarities and differences. We also show that disordered saturated sphere packings provide relatively thin (economical) coverings and may yield thinner coverings than the best known lattice coverings in sufficiently large dimensions. In the case of the quantizer problem, we derive improved upper
Directory of Open Access Journals (Sweden)
Ana-Raluca Chiriac
2006-01-01
Full Text Available Between structure, infrastructure (foundation and soil there is an effective interaction, which has to be taken into account as correctly as possible every time we do the calculation. This effective interaction can be analysed in a global form, considering on one hand the entire building, and on the other hand the soil -- establishment surface, or in an analytical form: we consider first the soil -- infrastructure (foundation interaction and then the structure -- infrastructure one. Without considering the interaction, we cannot make neither the calculation (for the soil according to the limiting deformation state which has to be compatible with the structure’s resistance system, nor calculation for the limiting resistance state, because the correct distribution of efforts along the contact surface between the soil and the structure is unknown, so we cannot determine the zones of plastical equilibrium in the soil massive and the conditions of limited equilibrium. Also, without considering the infrastructure, we cannot correctly calculate the efforts and the deformations which may occur in all resistance elements of the building. Therefore, we cannot talk about limiting state calculation without considering the interaction between the soil and the structure itself. The problem of interaction between building, on one hand and soil foundation, on the other hand, is not approached very much in the specialized literature, because of the big difficulties raised by summarizing all the factors that describe the structure and the environment, which would be more accessible to a practical calculation. A lot of buildings or elements of buildings standing on the soil or on another environment with finite rigidity can be taken into account as beams supported on a straining environment, (continuous foundations, resistance walls, longitudinal and transversal membranes of civil and industrial buildings, hydrotechnic works. Therefore, in the present paper we
Ceberio, Mikel; Almudí, José Manuel; Franco, Ángel
2016-08-01
In recent years, interactive computer simulations have been progressively integrated in the teaching of the sciences and have contributed significant improvements in the teaching-learning process. Practicing problem-solving is a key factor in science and engineering education. The aim of this study was to design simulation-based problem-solving teaching materials and assess their effectiveness in improving students' ability to solve problems in university-level physics. Firstly, we analyze the effect of using simulation-based materials in the development of students' skills in employing procedures that are typically used in the scientific method of problem-solving. We found that a significant percentage of the experimental students used expert-type scientific procedures such as qualitative analysis of the problem, making hypotheses, and analysis of results. At the end of the course, only a minority of the students persisted with habits based solely on mathematical equations. Secondly, we compare the effectiveness in terms of problem-solving of the experimental group students with the students who are taught conventionally. We found that the implementation of the problem-solving strategy improved experimental students' results regarding obtaining a correct solution from the academic point of view, in standard textbook problems. Thirdly, we explore students' satisfaction with simulation-based problem-solving teaching materials and we found that the majority appear to be satisfied with the methodology proposed and took on a favorable attitude to learning problem-solving. The research was carried out among first-year Engineering Degree students.
Co-simulation coupling spectral/finite elements for 3D soil/structure interaction problems
Zuchowski, Loïc; Brun, Michael; De Martin, Florent
2018-05-01
The coupling between an implicit finite elements (FE) code and an explicit spectral elements (SE) code has been explored for solving the elastic wave propagation in the case of soil/structure interaction problem. The coupling approach is based on domain decomposition methods in transient dynamics. The spatial coupling at the interface is managed by a standard coupling mortar approach, whereas the time integration is dealt with an hybrid asynchronous time integrator. An external coupling software, handling the interface problem, has been set up in order to couple the FE software Code_Aster with the SE software EFISPEC3D.
Mayasari, Ruth; Mawengkang, Herman; Gomar Purba, Ronal
2018-02-01
Land revitalization refers to comprehensive renovation of farmland, waterways, roads, forest or villages to improve the quality of plantation, raise the productivity of the plantation area and improve agricultural production conditions and the environment. The objective of sustainable land revitalization planning is to facilitate environmentally, socially, and economically viable land use. Therefore it is reasonable to use participatory approach to fullfil the plan. This paper addresses a multicriteria decision aid to model such planning problem, then we develop an interactive approach for solving the problem.
Discrete and continuum links to a nonlinear coupled transport problem of interacting populations
Duong, M. H.; Muntean, A.; Richardson, O. M.
2017-07-01
We are interested in exploring interacting particle systems that can be seen as microscopic models for a particular structure of coupled transport flux arising when different populations are jointly evolving. The scenarios we have in mind are inspired by the dynamics of pedestrian flows in open spaces and are intimately connected to cross-diffusion and thermo-diffusion problems holding a variational structure. The tools we use include a suitable structure of the relative entropy controlling TV-norms, the construction of Lyapunov functionals and particular closed-form solutions to nonlinear transport equations, a hydrodynamics limiting procedure due to Philipowski, as well as the construction of numerical approximates to both the continuum limit problem in 2D and to the original interacting particle systems.
Storti, Mario A.; Nigro, Norberto M.; Paz, Rodrigo R.; Dalcín, Lisandro D.
2009-03-01
In this paper some results on the convergence of the Gauss-Seidel iteration when solving fluid/structure interaction problems with strong coupling via fixed point iteration are presented. The flow-induced vibration of a flat plate aligned with the flow direction at supersonic Mach number is studied. The precision of different predictor schemes and the influence of the partitioned strong coupling on stability is discussed.
Marmorstein, Naomi R
2017-09-01
Background: Energy drink consumption and sleep problems are both associated with alcohol use among adolescents. In addition, caffeine consumption (including energy drinks) is associated with sleep problems. However, information about how these three constructs may interact is limited. The goal of this study was to examine potential interactions between energy drink consumption and sleep problems in the concurrent prediction of alcohol use among young adolescents. Coffee and soda consumption were also examined for comparison. Methods: Participants from the Camden Youth Development Study were included ( n = 127; mean age = 13.1; 68% Hispanic, 29% African American) and questionnaire measures of frequency of caffeinated beverage consumption (energy drinks, coffee, and soda), sleep (initial insomnia, sleep disturbances, daytime fatigue, and sleep duration), and alcohol consumption were used. Regression analyses were conducted to examine interactions between caffeinated beverage consumption and sleep in the concurrent prediction of alcohol use. Results: Energy drink consumption interacted with initial insomnia and daytime fatigue to concurrently predict particularly frequent alcohol use among those with either of these sleep-related problems and energy drink consumption. The pattern of results for coffee consumption was similar for insomnia but reached only a trend level of significance. Results of analyses examining soda consumption were nonsignificant. Conclusions: Young adolescents who both consume energy drinks and experience initial insomnia and/or daytime fatigue are at particularly high risk for alcohol use. Coffee consumption appears to be associated with similar patterns. Longitudinal research is needed to explain the developmental pathways by which these associations emerge, as well as mediators and moderators of these associations.
Balta, Nuri; Awedh, Mohammad Hamza
2016-01-01
Advanced technology helps educational institutes to improve student learning performance and outcomes. In this study, our aim is to measure and assess student engagement and collaborative learning in engineering classes when using online technology in solving physics problems. The interactive response system used in this study is a collaborative learning tool that allows teachers to monitor their students’ response and progress in real time. Our results indicated that students have highly pos...
TPLOT: An interactive data management system for transient problems 3. Edition
International Nuclear Information System (INIS)
Doron, R.
1988-01-01
This report describes the use of an interactive data management system suitable for post-processing of transient structural problems. The system is designed for IBM compatible environment (TSO command procedures) and makes use of PLOT-10 (TEKTRONIX) for graphical output (time plots). Interfaces are provided for experimental data and for various programs used in fast reactor safety analysis (EURDYN, SEURBNUK, ASTARTE, FRAP-T5, RODSWELL, SIMMER, TRACRUF, PHEAT, JOULE). Some examples are given to illustrate the system
Muhtadie, Luma; Zhou, Qing; Eisenberg, Nancy; Wang, Yun
2013-01-01
The additive and interactive relations of parenting styles (authoritative and authoritarian parenting) and child temperament (anger/frustration, sadness, and effortful control) to children’s internalizing problems were examined in a 3.8-year longitudinal study of 425 Chinese children (6 – 9 years) from Beijing. At Wave 1, parents self-reported on their parenting styles, and parents and teachers rated child temperament. At Wave 2, parents, teachers, and children rated children’s internalizing ...
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Wang Yong
2011-10-01
Full Text Available Abstract Background With the development of genome-sequencing technologies, protein sequences are readily obtained by translating the measured mRNAs. Therefore predicting protein-protein interactions from the sequences is of great demand. The reason lies in the fact that identifying protein-protein interactions is becoming a bottleneck for eventually understanding the functions of proteins, especially for those organisms barely characterized. Although a few methods have been proposed, the converse problem, if the features used extract sufficient and unbiased information from protein sequences, is almost untouched. Results In this study, we interrogate this problem theoretically by an optimization scheme. Motivated by the theoretical investigation, we find novel encoding methods for both protein sequences and protein pairs. Our new methods exploit sufficiently the information of protein sequences and reduce artificial bias and computational cost. Thus, it significantly outperforms the available methods regarding sensitivity, specificity, precision, and recall with cross-validation evaluation and reaches ~80% and ~90% accuracy in Escherichia coli and Saccharomyces cerevisiae respectively. Our findings here hold important implication for other sequence-based prediction tasks because representation of biological sequence is always the first step in computational biology. Conclusions By considering the converse problem, we propose new representation methods for both protein sequences and protein pairs. The results show that our method significantly improves the accuracy of protein-protein interaction predictions.
Muhtadie, Luma; Zhou, Qing; Eisenberg, Nancy; Wang, Yun
2012-01-01
The additive and interactive relations of parenting styles (authoritative and authoritarian parenting) and child temperament (anger/frustration, sadness, and effortful control) to children’s internalizing problems were examined in a 3.8-year longitudinal study of 425 Chinese children (6 – 9 years) from Beijing. At Wave 1, parents self-reported on their parenting styles, and parents and teachers rated child temperament. At Wave 2, parents, teachers, and children rated children’s internalizing problems. Structural equation modeling indicated that the main effect of authoritative parenting, and the interactions of authoritarian parenting × effortful control and authoritative parenting × anger/frustration (parents’ reports only) prospectively and uniquely predicted internalizing problems. The above results did not vary by child sex and remained significant after controlling for co-occurring externalizing problems. These findings suggest that: a) children with low effortful control may be particularly susceptible to the adverse effect of authoritarian parenting, and b) the benefit of authoritative parenting may be especially important for children with high anger/frustration. PMID:23880383
Muhtadie, Luma; Zhou, Qing; Eisenberg, Nancy; Wang, Yun
2013-08-01
The additive and interactive relations of parenting styles (authoritative and authoritarian parenting) and child temperament (anger/frustration, sadness, and effortful control) to children's internalizing problems were examined in a 3.8-year longitudinal study of 425 Chinese children (aged 6-9 years) from Beijing. At Wave 1, parents self-reported on their parenting styles, and parents and teachers rated child temperament. At Wave 2, parents, teachers, and children rated children's internalizing problems. Structural equation modeling indicated that the main effect of authoritative parenting and the interactions of Authoritarian Parenting × Effortful Control and Authoritative Parenting × Anger/Frustration (parents' reports only) prospectively and uniquely predicted internalizing problems. The above results did not vary by child sex and remained significant after controlling for co-occurring externalizing problems. These findings suggest that (a) children with low effortful control may be particularly susceptible to the adverse effect of authoritarian parenting and (b) the benefit of authoritative parenting may be especially important for children with high anger/frustration.
Endendijk, Joyce J; De Bruijn, Anouk T C E; Van Bakel, Hedwig J A; Wijnen, Hennie A A; Pop, Victor J M; Van Baar, Anneloes L
2017-09-01
The role of mother-infant interaction quality is studied in the relation between prenatal maternal emotional symptoms and child behavioral problems. Healthy pregnant, Dutch women (N = 96, M = 31.6, SD = 3.3) were allocated to the "exposed group" (n = 46), consisting of mothers with high levels of prenatal feelings of anxiety and depression, or the "low-exposed group" (n = 50), consisting of mothers with normal levels of depressive or anxious symptoms during pregnancy. When the children (49 girls, 47 boys) were 23 to 60 months of age (M = 39.0, SD = 9.6), parents completed the Child Behavior Checklist (T.M. Achenbach & L.A. Rescorla, ), and mother-child interaction quality during a home visit was rated using the Emotional Availability Scales. There were no differences in mother-child interaction quality between the prenatally exposed and low-exposed groups. Girls exposed to high prenatal emotional symptoms showed more internalizing problems, if maternal interaction quality was less optimal. No significant effects were found for boys. © 2017 Michigan Association for Infant Mental Health.
The interaction problems between large and small business in modern conditions
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Belyaev Mikhail
2017-01-01
Full Text Available The development of market relations, changes of the conditions in the business environment encourage the enterprises to look for new management methods and to improve forms of interaction. In this regard, the identification of the interaction of large and small businesses, as well as the evaluation of their relation development seems important and urgent problem in modern conditions. The purpose of the survey – the study of the interaction of large and small businesses, as well as the evaluation of the relations between them. The study was conducted on the basis of a comprehensive and systematic approach in which methods of comparative, retrospective, statistical, mathematical analysis are used. In accordance with the purpose there are identified the prerequisites for the development of large and small businesses, features and their functioning problems, and the links between them. The most common form of interaction of large and small enterprises were identified - outsourcing, franchising, leasing, subcontracting, venture financing, the establishment of regional cooperation forms of large and small businesses. However, the cooperative processes of large and small business in Russia developed are not enough today.The authors identified factors that impede the growth of Russian production, offered recommendations for the development of large and small businesses, justified the state's role in this process. In addition, they described the mechanism of state support of small business, including organizational, financial, information and consulting components.
Ochi, Manami; Fujiwara, Takeo
2016-08-01
Research in parental social support has chiefly examined received social support. Studies have suggested that provided social support may also be protective for child mental health problems. We aim to investigate the association between parental social interaction (both received and provided social support) and offspring behavior problems. We analyzed the data of 982 households, including 1538 children aged 4 to 16 years, from the Japanese Study of Stratification, Health, Income, and Neighborhood (J-SHINE) survey conducted over 2010-2011. We used a 5-point Likert scale to assess social interaction including parental emotional and instrumental support received from and provided to the spouse, other co-residing family members, non-co-residing family members or relatives, neighbors, and friends. Behavior problems in offspring were assessed using parental responses to the Strengths and Difficulties Questionnaire. Associations between parental social interaction and behavior problems were analyzed using ordered logistic regression. We found that higher maternal social interaction is significantly associated with lower odds of both difficult and prosocial behavior problems, while the same associations were not found for paternal social interaction. Further, maternal provided social support showed an independent negative association with prosocial behavior problems in offspring, even when adjusted for received maternal social support and paternal social interaction. This study showed that maternal social interaction, but not paternal social interaction, might have a protective effect on offspring behavior problems. Further study is required to investigate the effect of the intervention to increase social participation among mothers whose children have behavior problems.
Interactive and Indirect Effects of Anxiety and Negative Urgency on Alcohol-Related Problems
Menary, Kyle R.; Corbin, William R.; Leeman, Robert F.; Fucito, Lisa M.; Toll, Benjamin A.; DeMartini, Kelly; O’Malley, Stephanie S.
2015-01-01
Background Although drinking for tension reduction has long been posited as a risk factor for alcohol-related problems, studies investigating anxiety in relation to risk for alcohol problems have returned inconsistent results, leading researchers to search for potential moderators. Negative urgency (the tendency to become behaviorally dysregulated when experiencing negative affect) is a potential moderator of theoretical interest because it may increase risk for alcohol problems among those high in negative affect. The present study tested a cross-sectional mediated moderation hypothesis whereby an interactive effect of anxiety and negative urgency on alcohol problems is mediated through coping-related drinking motives. Method The study utilized baseline data from a hazardously drinking sample of young adults (N = 193) evaluated for participation in a randomized controlled trial of naltrexone and motivational interviewing for drinking reduction. Results The direct effect of anxiety on physiological dependence symptoms was moderated by negative urgency such that the positive association between anxiety and physiological dependence symptoms became stronger as negative urgency increased. Indirect effects of anxiety and negative urgency on alcohol problems (operating through coping motives) were also observed. Conclusions Although results of the current cross-sectional study require replication using longitudinal data, the findings suggest that the simultaneous presence of anxiety and negative urgency may be an important indicator of risk for AUDs via both direct interactive effects and indirect additive effects operating through coping motives. These findings have potentially important implications for prevention/intervention efforts for individuals who become disinhibited in the context of negative emotional states. PMID:26031346
Interactions of relativistic heavy ions in thick heavy element targets and some unresolved problems
International Nuclear Information System (INIS)
Brandt, R.; Ditlov, V.A.; Pozharova, E.A.; Smirnitskij, V.A.
2005-01-01
Interactions of relativistic heavy ions with total energies above 30 GeV in thick Cu and Pb targets (≥2 cm) have been studied with various techniques. Radiochemical irradiation experiments using thick Cu targets, both in a compact form or as diluted '2π-Cu targets' have been carried out with several relativistic heavy ions, such as 44 GeV 12 C (JINR, Dubna) and 72 GeV 40 Ar (LBL, Berkeley, USA). Neutron measuring experiments using thick targets irradiated with various relativistic heavy ions up to 44 GeV 12 C have been performed at JINR. In addition, the number of 'black prongs' in nuclear interactions (due to protons with energies less than 30 MeV and emitted from the target-like interaction partner at rest) produced with 72 GeV 22 Ne ions in nuclear emulsion plates has been measured in the first nuclear interaction of the primary 22 Ne ion and in the following second nuclear interaction of the secondary heavy (Z>1) ion. Some essential results have been obtained. 1) Spallation products produced by relativistic secondary fragments in interactions ([44 GeV 12 C or 72 GeV 40 Ar]+Cu) within thick copper yield less products close to the target and much more products far away from the target as compared to primary beam interactions. This applies also to secondary particles emitted into large angles (Θ>10deg). 2) The neutron production of 44 GeV 12 C within thick Cu and Pb targets is beyond the estimated yield as based on experiments with 12 GeV 12 C. These rather independent experimental results cannot be understood with well-accepted nuclear reaction models. They appear to present unresolved problems
On the Validation of a Numerical Model for the Analysis of Soil-Structure Interaction Problems
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Jorge Luis Palomino Tamayo
Full Text Available Abstract Modeling and simulation of mechanical response of structures, relies on the use of computational models. Therefore, verification and validation procedures are the primary means of assessing accuracy, confidence and credibility in modeling. This paper is concerned with the validation of a three dimensional numerical model based on the finite element method suitable for the dynamic analysis of soil-structure interaction problems. The soil mass, structure, structure's foundation and the appropriate boundary conditions can be represented altogether in a single model by using a direct approach. The theory of porous media of Biot is used to represent the soil mass as a two-phase material which is considered to be fully saturated with water; meanwhile other parts of the system are treated as one-phase materials. Plasticity of the soil mass is the main source of non-linearity in the problem and therefore an iterative-incremental algorithm based on the Newton-Raphson procedure is used to solve the nonlinear equilibrium equations. For discretization in time, the Generalized Newmark-β method is used. The soil is represented by a plasticity-based, effective-stress constitutive model suitable for liquefaction. Validation of the present numerical model is done by comparing analytical and centrifuge test results of soil and soil-pile systems with those results obtained with the present numerical model. A soil-pile-structure interaction problem is also presented in order to shown the potentiality of the numerical tool.
Self-interacting inelastic dark matter: a viable solution to the small scale structure problems
Energy Technology Data Exchange (ETDEWEB)
Blennow, Mattias; Clementz, Stefan; Herrero-Garcia, Juan, E-mail: emb@kth.se, E-mail: scl@kth.se, E-mail: juan.herrero-garcia@adelaide.edu.au [Department of Physics, School of Engineering Sciences, KTH Royal Institute of Technology, AlbaNova University Center, 106 91 Stockholm (Sweden)
2017-03-01
Self-interacting dark matter has been proposed as a solution to the small-scale structure problems, such as the observed flat cores in dwarf and low surface brightness galaxies. If scattering takes place through light mediators, the scattering cross section relevant to solve these problems may fall into the non-perturbative regime leading to a non-trivial velocity dependence, which allows compatibility with limits stemming from cluster-size objects. However, these models are strongly constrained by different observations, in particular from the requirements that the decay of the light mediator is sufficiently rapid (before Big Bang Nucleosynthesis) and from direct detection. A natural solution to reconcile both requirements are inelastic endothermic interactions, such that scatterings in direct detection experiments are suppressed or even kinematically forbidden if the mass splitting between the two-states is sufficiently large. Using an exact solution when numerically solving the Schrödinger equation, we study such scenarios and find regions in the parameter space of dark matter and mediator masses, and the mass splitting of the states, where the small scale structure problems can be solved, the dark matter has the correct relic abundance and direct detection limits can be evaded.
Perturbation theory of intermolecular interactions: What is the problem, are there solutions?
International Nuclear Information System (INIS)
Adams, W.H.
1990-01-01
We review the nature of the problem in the framework of Rayleigh-Schroedinger perturbation theory (the polarization approximation) considering explicitly two examples: the interaction of two hydrogen atoms and the interaction of Li with H. We show, in agreement with the work of Claverie and of Morgan and Simon, that the LiH problem is dramatically different from the H 2 problem. In particular, the physical states of LiH are higher in energy than an infinite number of discrete, unphysical states and they are buried in a continuum of unbound, unphysical states, which starts well below the lowest physical state. Clavrie has shown that the perturbation expansion, under these circumstances, is likely to converge to an unphysical state of lower energy than the physical ground state, if it converges at all. We review, also, the application of two classes of exchange perturbation theory to LiH and larger systems. We show that the spectra of three Eisenschitz-London (EL) class, exchange perturbation theories have no continuum of unphysical states overlaying the physical states and no discrete, unphysical states below the lowest physical state. In contrast, the spectra of two Hirschfelder-Silbey class theories differ hardly at all from that found with the polarization approximation. Not one of the EL class of perturbation theories, however, eliminates all of the discrete unphysical states
Miyauchi, Suguru; Takeuchi, Shintaro; Kajishima, Takeo
2017-09-01
We develop a numerical method for fluid-membrane interaction accounting for permeation of the fluid using a non-conforming mesh to the membrane shape. To represent the permeation flux correctly, the proposed finite element discretization incorporates the discontinuities in the velocity gradient and pressure on the membrane surface with specially selected base functions. The discontinuities are represented with independent variables and determined to satisfy the governing equations including the interfacial condition on the permeation. The motions of the fluid, membrane and permeation flux are coupled monolithically and time-advanced fully-implicitly. The validity and effectiveness of the proposed method are demonstrated by several two-dimensional fluid-membrane interaction problems of Stokes flows by comparing with the analytical models and numerical results obtained by other methods. The reproduced sharp discontinuities are found to be essential to suppress the non-physical permeation flux. Further, combined with the numerical treatment for the solute concentration across the membrane, the proposed method is applied to a fluid-structure interaction problem including the osmotic pressure difference.
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Meyer Dirk
2012-02-01
Full Text Available Abstract Background The degree to which loud-calls in nonhuman primates can be used as a reliable taxonomic tool is the subject of ongoing debate. A recent study on crested gibbons showed that these species can be well distinguished by their songs; even at the population level the authors found reliable differences. Although there are some further studies on geographic and phylogenetic differences in loud-calls of nonhuman primate species, it is unclear to what extent loud-calls of other species have a similar close relation between acoustic structure, phylogenetic relatedness and geographic distance. We therefore conducted a field survey in 19 locations on Sumatra, Java and the Mentawai islands to record male loud-calls of wild surilis (Presbytis, a genus of Asian leaf monkeys (Colobinae with disputed taxanomy, and compared the structure of their loud-calls with a molecular genetic analysis. Results The acoustic analysis of 100 surili male loud-calls from 68 wild animals confirms the differentiation of P.potenziani, P.comata, P.thomasi and P.melalophos. In a more detailed acoustic analysis of subspecies of P.melalophos, a further separation of the southern P.m.mitrata confirms the proposed paraphyly of this group. In concordance with their geographic distribution we found the highest correlation between call structure and genetic similarity, and lesser significant correlations between call structure and geographic distance, and genetic similarity and geographic distance. Conclusions In this study we show, that as in crested gibbons, the acoustic structure of surili loud-calls is a reliable tool to distinguish between species and to verify phylogenetic relatedness and migration backgrounds of respective taxa. Since vocal production in other nonhuman primates show similar constraints, it is likely that an acoustic analysis of call structure can help to clarify taxonomic and phylogenetic relationships.
Using Interactive Case Studies to Support Students Understandings of Local Environmental Problems
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Z. Kostova
2012-12-01
Full Text Available The article presents designed and refined an interactive-enhanced curriculum module for 9th grade secondary school students in Bulgaria, based on environmental case studies. In the module activities students from two schools studied the local environments, performed observations and experiments, collected and analyzed data, prepared and presented posters and role plays, made connections between scientific processes and socio-scientific issues and drew conclusions about the global effects of locally created environmental problems. The students’ critical observations of the quality of their surroundings helped them to make a list of local environmental problems, to apply interactive strategies in studying them and to propose rational scientifically based solutions. In the study the attention was directed to the advantages and disadvantages of poster presentations and role playing and to the specific learning difficulties that students had to overcome. Students’ achievements from the two experimental schools were assessed independently in order to give us insights into the details of learning using different interactive strategies and into the acquired performance skills, dependant on students’ interests and personal abilities. The three versions of the module (traditional, dominated by teacher presentation; poster preparation and presentation in which students imitate scientific team research; and role playing in which students not only study the local environmental problems but assume social roles to cope with them demonstrate three levels of students learning independence. Specific assessment tests and check lists were developed for analyzing, evaluating and comparing students’ achievements in each version of the module and in each school. Ecological knowledge assessment tests were based on Bloom’s taxonomy of educational objectives. Poster and role playing preparations and presentations were assessed by specific criteria, shown in the
Gulland, E.-K.; Veenendaal, B.; Schut, A. G. T.
2012-07-01
Problem-solving knowledge and skills are an important attribute of spatial sciences graduates. The challenge of higher education is to build a teaching and learning environment that enables students to acquire these skills in relevant and authentic applications. This study investigates the effectiveness of traditional face-to-face teaching and online learning technologies in supporting the student learning of problem-solving and computer programming skills, techniques and solutions. The student cohort considered for this study involves students in the surveying as well as geographic information science (GISc) disciplines. Also, students studying across a range of learning modes including on-campus, distance and blended, are considered in this study. Student feedback and past studies reveal a lack of student interest and engagement in problem solving and computer programming. Many students do not see such skills as directly relevant and applicable to their perceptions of what future spatial careers hold. A range of teaching and learning methods for both face-to-face teaching and distance learning were introduced to address some of the perceived weaknesses of the learning environment. These included initiating greater student interaction in lectures, modifying assessments to provide greater feedback and student accountability, and the provision of more interactive and engaging online learning resources. The paper presents and evaluates the teaching methods used to support the student learning environment. Responses of students in relation to their learning experiences were collected via two anonymous, online surveys and these results were analysed with respect to student pass and retention rates. The study found a clear distinction between expectations and engagement of surveying students in comparison to GISc students. A further outcome revealed that students who were already engaged in their learning benefited the most from the interactive learning resources and
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E.-K. Gulland
2012-07-01
Full Text Available Problem-solving knowledge and skills are an important attribute of spatial sciences graduates. The challenge of higher education is to build a teaching and learning environment that enables students to acquire these skills in relevant and authentic applications. This study investigates the effectiveness of traditional face-to-face teaching and online learning technologies in supporting the student learning of problem-solving and computer programming skills, techniques and solutions. The student cohort considered for this study involves students in the surveying as well as geographic information science (GISc disciplines. Also, students studying across a range of learning modes including on-campus, distance and blended, are considered in this study. Student feedback and past studies reveal a lack of student interest and engagement in problem solving and computer programming. Many students do not see such skills as directly relevant and applicable to their perceptions of what future spatial careers hold. A range of teaching and learning methods for both face-to-face teaching and distance learning were introduced to address some of the perceived weaknesses of the learning environment. These included initiating greater student interaction in lectures, modifying assessments to provide greater feedback and student accountability, and the provision of more interactive and engaging online learning resources. The paper presents and evaluates the teaching methods used to support the student learning environment. Responses of students in relation to their learning experiences were collected via two anonymous, online surveys and these results were analysed with respect to student pass and retention rates. The study found a clear distinction between expectations and engagement of surveying students in comparison to GISc students. A further outcome revealed that students who were already engaged in their learning benefited the most from the interactive
Zemore, Sarah E.; Karriker-Jaffe, Katherine J.; Keithly, Sarah; Mulia, Nina
2011-01-01
Objective: Although racial and ethnic minorities are often disadvantaged in multiple ways, little research has examined the interactive effects of multiple forms of disadvantage in these populations. The current study describes the independent and interactive effects of perceived prejudice, perceived unfair treatment, poverty, and foreign nativity on problem drinking outcomes among Black and Latino adults. Method: The data source was Black (n = 504) and Latino (n = 766) drinkers from the nationally representative, weighted 2005 National Alcohol Survey. Perceived prejudice was assessed using a composite measure of racial stigma consciousness; perceived unfair treatment was assessed using a single item. Respondents whose per capita household income was below the 2004 poverty guidelines were coded as “poor”; nativity status was assessed among Latinos. Outcomes included past-year drinking to drunkenness, any drinking-related consequences, and two or more dependence symptoms. Results: In bivariate tests, higher levels of unfair treatment were significantly associated with all three outcomes among Blacks (marginally so for drunkenness) and dependence symptoms among Latinos. Further, higher racial stigma was significantly associated with higher rates of any drinking consequences among Latinos. In multivariate logistic regressions, six significant or marginally significant interactions emerged. For each, the pattern of results suggested stronger associations between perceived prejudice/unfair treatment and problem drinking given either poverty or foreign nativity. Conclusions: Although findings were somewhat mixed, the pattern of results tentatively supports the hypothesis that associations between problem drinking and both prejudice and unfair treatment can be exacerbated given the presence of other stressors, particularly among Latinos. Results extend the literature on the health consequences of prejudice and discrimination, highlighting important effects of
A parallel graded-mesh FDTD algorithm for human-antenna interaction problems.
Catarinucci, Luca; Tarricone, Luciano
2009-01-01
The finite difference time domain method (FDTD) is frequently used for the numerical solution of a wide variety of electromagnetic (EM) problems and, among them, those concerning human exposure to EM fields. In many practical cases related to the assessment of occupational EM exposure, large simulation domains are modeled and high space resolution adopted, so that strong memory and central processing unit power requirements have to be satisfied. To better afford the computational effort, the use of parallel computing is a winning approach; alternatively, subgridding techniques are often implemented. However, the simultaneous use of subgridding schemes and parallel algorithms is very new. In this paper, an easy-to-implement and highly-efficient parallel graded-mesh (GM) FDTD scheme is proposed and applied to human-antenna interaction problems, demonstrating its appropriateness in dealing with complex occupational tasks and showing its capability to guarantee the advantages of a traditional subgridding technique without affecting the parallel FDTD performance.
Adaptive solution of some steady-state fluid-structure interaction problems
International Nuclear Information System (INIS)
Etienne, S.; Pelletier, D.
2003-01-01
This paper presents a general integrated and coupled formulation for modeling the steady-state interaction of a viscous incompressible flow with an elastic structure undergoing large displacements (geometric non-linearities). This constitutes an initial step towards developing a sensitivity analysis formulation for this class of problems. The formulation uses velocity and pressures as unknowns in a flow domain and displacements in the structural components. An interface formulation is presented that leads to clear and simple finite element implementation of the equilibrium conditions at the fluid-solid interface. Issues of error estimation and mesh adaptation are discussed. The adaptive formulation is verified on a problem with a closed form solution. It is then applied to a sample case for which the structure undergoes large displacements induced by the flow. (author)
A method for solving a three-body problem with energy-dependent interactions
International Nuclear Information System (INIS)
Safronov, A.N.
1994-01-01
A method is proposed for solving a three-body problem with energy-dependent interactions. This method is based on introducing the dependence of scattering operators and state vectors on an additional external parameter. Effects caused by the energy dependence of the interaction operator are investigated by using the unitary condition for the amplitude of the 2 → 2 and 2 → 3 transitions. It is shown, in particular, that taking this dependence into account leads to a change in the relation between the asymptotic normalization factor of the wave function of the three-body bound state and the vertex constant of virtual dissociation (synthesis) of the system into two fragments. 15 refs
Lamont, L. A.; Chaar, L.; Toms, C.
2010-03-01
Interactive learning is beneficial to students in that it allows the continual development and testing of many skills. An interactive approach enables students to improve their technical capabilities, as well as developing both verbal and written communicative ability. Problem solving and communication skills are vital for engineering students; in the workplace they will be required to communicate with people of varying technical abilities and from different linguistic and engineering backgrounds. In this paper, a case study is presented that discusses how the traditional method of teaching control systems can be improved. 'Control systems' is a complex engineering topic requiring students to process an extended amount of mathematical formulae. MATLAB software, which enables students to interactively compare a range of possible combinations and analyse the optimal solution, is used to this end. It was found that students became more enthusiastic and interested when given ownership of their learning objectives. As well as improving the students' technical knowledge, other important engineering skills are also improved by introducing an interactive method of teaching.
Experimental problems of search for quark-gluon plasma in nucleus-nucleus interactions
International Nuclear Information System (INIS)
Okonov, Eh.O.
1987-01-01
Experimental problems for searching for quark-gluon (quagma) plasma in nucleus-nucleus interactions (NbNb,CaCa, ArPb, CnE, ONe) in the energy range E=0.4-1 GeV/A and 3.67 GeV/A and 200 GeV/A energies are discussed. Peculiarities of performing experiments on Dubna synchrophasotron and SPS Bevalac are discussed. The first results prove hadron matter thermalization sufficient for quagma manifestation. It is found that such characteristics of studied interactions as relative λ-hyperon yield, spectral (temperature) characteristics of λ k -hyperons (with higher values of transferred transverse momenta) and associatively produced peons are of greatest interest. The necessity of precise establishment of λ-hyperon group as excessive and differing in its origin from the other particles of the hadron phase is noted. It is shown that experimental approach used in Dubna research proved efficient and requires further development. It includes : selection of rare events (fluctuations) in central interactions of nuclei with high local excitation; search and research of peculiarities in the production of strange particles and in associative pion production; use of streamer spectrometer with a trigger system of rigid selection of central interactions
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Claudia M. Colciago
2018-06-01
Full Text Available This paper deals with fast simulations of the hemodynamics in large arteries by considering a reduced model of the associated fluid-structure interaction problem, which in turn allows an additional reduction in terms of the numerical discretisation. The resulting method is both accurate and computationally cheap. This goal is achieved by means of two levels of reduction: first, we describe the model equations with a reduced mathematical formulation which allows to write the fluid-structure interaction problem as a Navier-Stokes system with non-standard boundary conditions; second, we employ numerical reduction techniques to further and drastically lower the computational costs. The non standard boundary condition is of a generalized Robin type, with a boundary mass and boundary stiffness terms accounting for the arterial wall compliance. The numerical reduction is obtained coupling two well-known techniques: the proper orthogonal decomposition and the reduced basis method, in particular the greedy algorithm. We start by reducing the numerical dimension of the problem at hand with a proper orthogonal decomposition and we measure the system energy with specific norms; this allows to take into account the different orders of magnitude of the state variables, the velocity and the pressure. Then, we introduce a strategy based on a greedy procedure which aims at enriching the reduced discretization space with low offline computational costs. As application, we consider a realistic hemodynamics problem with a perturbation in the boundary conditions and we show the good performances of the reduction techniques presented in the paper. The results obtained with the numerical reduction algorithm are compared with the one obtained by a standard finite element method. The gains obtained in term of CPU time are of three orders of magnitude.
Exact results for the many-body problem in one dimension with repulsive delta-function interaction
International Nuclear Information System (INIS)
Yang, C.N.
1983-01-01
The repulsive δ interaction problem in one dimension for N particles is reduced, through the use of Bethe's hypothesis, to an eigenvalue problem of matrices of the same sizes as the irreducible representations R of the permutation group S/sub N/. For some R's this eigenvalue problem itself is solved by a second use of Bethe's hypothesis, in a generalized form. In particular, the ground-state problem of spin-1/2 fermions is reduced to a generalized Fredholm equation
Interacting dark energy models as an approach for solving Cosmic Coincidence Problem
Shojaei, Hamed
Understanding the dark side of the Universe is one of the main tasks of physicists. As there is no thorough understanding of nature of the dark energy, this area is full of new ideas and there may be several discoveries, theoretical or experimental, in the near future. We know that dark energy, though not detected directly, exists and it is not just an exotic idea. The presence of dark energy is required by the observation of the acceleration of the universe. There are several questions regarding dark energy. What is the nature of dark energy? How does it interact with matter, baryonic or dark? Why is the density of dark energy so tiny, i.e. why rhoΛ ≈ 10--120 M4Pl ? And finally why does its density have the same order of magnitude as the density of matter does at the present time? The last question is one form of what is known as the "Cosmic Coincidence Problem" and in this work, I have been investigating one way to resolve this issue. Observations of Type Ia supernovae indicate that we are in an accelerating universe. A matter-dominated universe cannot be accelerating. A good fit is obtained if we assume that energy density parameters are O Λ = 0.7 and Om = 0.3. Here O Λ is related to dark energy, or cosmological constant in ΛCDM model. At the same time data from Wilkinson Microwave Anisotropy Probe (WMAP) satellite and supernova surveys have placed a constraint on w, the equation of state for dark energy, which is actually the ratio of pressure and energy density. Any good theory needs to explain this coincidence problem and yields a value for w between -1.1 and -0.9. I have employed an interesting approach to solve this problem by assuming that there exists an interaction between dark energy and matter in the context of holographic dark energy. This interaction converts dark energy to matter or vice versa without violating the local conservation of energy in the universe. Holographic dark energy by itself indicates that the value of dark energy is related
Butt, N.; Pidlisecky, A.; Ganshorn, H.; Cockett, R.
2015-12-01
The software company 3 Point Science has developed three interactive learning programs designed to teach, test and practice visualization skills and geoscience concepts. A study was conducted with 21 geoscience students at the University of Calgary who participated in 2 hour sessions of software interaction and written pre and post-tests. Computer and SMART touch table interfaces were used to analyze user interaction, problem solving methods and visualization skills. By understanding and pinpointing user problem solving methods it is possible to reconstruct viewpoints and thought processes. This could allow us to give personalized feedback in real time, informing the user of problem solving tips and possible misconceptions.
Abrahamse, Mariëlle E; Junger, Marianne; Chavannes, E Lidewei; Coelman, Frederique J G; Boer, Frits; Lindauer, Ramón J L
2012-06-13
Persistent high levels of aggressive, oppositional and impulsive behaviours, in the early lives of children, are significant risk factors for adolescent and adult antisocial behaviour and criminal activity. If the disruptive behavioural problems of young children could be prevented or significantly reduced at an early age, the trajectory of these behavioural problems leading to adolescent delinquency and adult antisocial behaviour could be corrected. Parent-Child Interaction Therapy (PCIT) is a short-term, evidence-based, training intervention for parents dealing with preschool children, who exhibit behavioural problems. Recently, PCIT was implemented in a Dutch community mental health setting. This present study aims to examine the short-term effects of PCIT on reducing the frequency of disruptive behaviour in young children. This study is based on the data of 37 referred families. Whereby the results of which are derived from an analysis of parent reports of the Eyberg Child Behavior Inventory (ECBI), obtained during each therapeutic session. Furthermore, demographic information, extracted from client files, was also utilized. However, it must be noted that eleven families (27.5%) dropped out of treatment before the treatment protocol was completed. To investigate the development of disruptive behaviour, a non-clinical comparison group was recruited from primary schools (N = 59). The results of this study indicate that PCIT significantly reduces disruptive behaviour in children. Large effect sizes were found for both fathers and mothers reported problems (d = 1.88, d = 1.99, respectively), which is similar to American outcome studies. At post treatment, no differences were found concerning the frequency of behavioural problems of children who completed treatment and those who participated in the non-clinical comparison group. The findings of this study suggest that PCIT is potentially an effective intervention strategy for young children and their
Directory of Open Access Journals (Sweden)
Abrahamse Mariëlle E
2012-06-01
Full Text Available Abstract Background Persistent high levels of aggressive, oppositional and impulsive behaviours, in the early lives of children, are significant risk factors for adolescent and adult antisocial behaviour and criminal activity. If the disruptive behavioural problems of young children could be prevented or significantly reduced at an early age, the trajectory of these behavioural problems leading to adolescent delinquency and adult antisocial behaviour could be corrected. Parent–Child Interaction Therapy (PCIT is a short-term, evidence-based, training intervention for parents dealing with preschool children, who exhibit behavioural problems. Recently, PCIT was implemented in a Dutch community mental health setting. This present study aims to examine the short-term effects of PCIT on reducing the frequency of disruptive behaviour in young children. Methods This study is based on the data of 37 referred families. Whereby the results of which are derived from an analysis of parent reports of the Eyberg Child Behavior Inventory (ECBI, obtained during each therapeutic session. Furthermore, demographic information, extracted from client files, was also utilized. However, it must be noted that eleven families (27.5% dropped out of treatment before the treatment protocol was completed. To investigate the development of disruptive behaviour, a non-clinical comparison group was recruited from primary schools (N = 59. Results The results of this study indicate that PCIT significantly reduces disruptive behaviour in children. Large effect sizes were found for both fathers and mothers reported problems (d = 1.88, d = 1.99, respectively, which is similar to American outcome studies. At post treatment, no differences were found concerning the frequency of behavioural problems of children who completed treatment and those who participated in the non-clinical comparison group. Conclusion The findings of this study suggest that PCIT is potentially an
Mericle, Amy A; Kaskutas, Lee A; Polcin, Doug L; Karriker-Jaffe, Katherine J
2018-01-01
Socioecological approaches to public health problems like addiction emphasize the importance of person-environment interactions. Neighborhood and social network characteristics may influence the likelihood of relapse among individuals in recovery, but these factors have been understudied, particularly with respect to conceptualizing social network characteristics as moderators of neighborhood disadvantage. Drawing from a larger prospective study of individuals recruited from outpatient treatment (N=451) and interviewed 1, 3, 5, and 7 years later, the aim of this study was to examine the independent and interactive effects of neighborhood and social network characteristics on continued problem drinking after treatment. Models using generalized estimating equations controlling for demographic and other risk factors found the number of heavy drinkers in one's network increases risk of relapse, with the effects being significantly stronger among those living in disadvantaged neighborhoods than among those in non-disadvantaged neighborhoods. No independent effects were found for neighborhood disadvantage or for the number of network members supporting reduced drinking. Future research is needed to examine potential protective factors in neighborhoods which may offset socioeconomic disadvantage as well as to investigate the functions that network members serve in helping to improve long-term treatment outcomes.
Cartreine, James Albert; Locke, Steven E; Buckey, Jay C; Sandoval, Luis; Hegel, Mark T
2012-09-25
Computer-automated depression interventions rely heavily on users reading text to receive the intervention. However, text-delivered interventions place a burden on persons with depression and convey only verbal content. The primary aim of this project was to develop a computer-automated treatment for depression that is delivered via interactive media technology. By using branching video and audio, the program simulates the experience of being in therapy with a master clinician who provides six sessions of problem-solving therapy. A secondary objective was to conduct a pilot study of the program's usability, acceptability, and credibility, and to obtain an initial estimate of its efficacy. The program was produced in a professional multimedia production facility and incorporates video, audio, graphics, animation, and text. Failure analyses of patient data are conducted across sessions and across problems to identify ways to help the user improve his or her problem solving. A pilot study was conducted with persons who had minor depression. An experimental group (n = 7) used the program while a waitlist control group (n = 7) was provided with no treatment for 6 weeks. All of the experimental group participants completed the trial, whereas 1 from the control was lost to follow-up. Experimental group participants rated the program high on usability, acceptability, and credibility. The study was not powered to detect clinical improvement, although these pilot data are encouraging. Although the study was not powered to detect treatment effects, participants did find the program highly usable, acceptable, and credible. This suggests that the highly interactive and immersive nature of the program is beneficial. Further clinical trials are warranted. ClinicalTrials.gov NCT00906581; http://clinicaltrials.gov/ct2/show/NCT00906581 (Archived by WebCite at http://www.webcitation.org/6A5Ni5HUp).
Possibilities of the particle finite element method for fluid-soil-structure interaction problems
Oñate, Eugenio; Celigueta, Miguel Angel; Idelsohn, Sergio R.; Salazar, Fernando; Suárez, Benjamín
2011-09-01
We present some developments in the particle finite element method (PFEM) for analysis of complex coupled problems in mechanics involving fluid-soil-structure interaction (FSSI). The PFEM uses an updated Lagrangian description to model the motion of nodes (particles) in both the fluid and the solid domains (the later including soil/rock and structures). A mesh connects the particles (nodes) defining the discretized domain where the governing equations for each of the constituent materials are solved as in the standard FEM. The stabilization for dealing with an incompressibility continuum is introduced via the finite calculus method. An incremental iterative scheme for the solution of the non linear transient coupled FSSI problem is described. The procedure to model frictional contact conditions and material erosion at fluid-solid and solid-solid interfaces is described. We present several examples of application of the PFEM to solve FSSI problems such as the motion of rocks by water streams, the erosion of a river bed adjacent to a bridge foundation, the stability of breakwaters and constructions sea waves and the study of landslides.
Maslowsky, Julie; Schulenberg, John E
2013-11-01
Substance use is a major contributor to morbidity and mortality among American adolescents. Conduct problems and depressive symptoms have each been found to be associated with adolescent substance use. Although they are highly comorbid, the role of the interaction of conduct problems and depressive symptoms in substance use is not clear. In national samples of 8th-, 10th-, and 12th-grade students from the Monitoring the Future study, latent moderated structural equation modeling was used to estimate the association of conduct problems, depressive symptoms, and their interaction to the use of alcohol (including binge drinking), cigarettes, and marijuana. Moderation by age and sex was tested. The interaction of conduct problems with depressive symptoms was a strong predictor of substance use, particularly among younger adolescents. With few exceptions, adolescents with high levels of both conduct problems and depressive symptoms used substances most frequently. Conduct problems were a strong positive predictor of substance use, and depressive symptoms were a weak positive predictor. Whereas conduct problems are often thought to be a primary predictor of substance use, this study revealed that depressive symptoms potentiate the relation of conduct problems to substance use. Therefore, substance use prevention efforts should target both depressive symptoms and conduct problems.
Rentscher, Kelly E.; Rohrbaugh, Michael J.; Shoham, Varda; Mehl, Matthias R.
2014-01-01
Recent research links first-person plural pronoun use (we-talk) by individual romantic partners to adaptive relationship functioning and individual health outcomes. To examine a possible boundary condition of adaptive we-talk in couples coping with health problems, we correlated asymmetric couple-level we/I-ratios (more we-talk relative to I-talk by the spouse than the patient) with a concurrent pattern of directional demand-withdraw (D-W) interaction in which the spouse demands change while the patient withdraws. Couples in which a partner who abused alcohol (n = 65), smoked cigarettes despite having heart or lung disease (n = 24), or had congestive heart failure (n = 58) discussed a health-related disagreement during a video-recorded interaction task. Transcripts of these conversations provided measures of pronoun use for each partner, and trained observers coded D-W patterns from the recordings. As expected, partner asymmetry in we/I-ratio scores predicted directional demand-withdraw, such that spouses who used more we-talk (relative to I-talk) than patients tended to assume the demand role in concurrent D-W interaction. Asymmetric I-talk rather than we-talk accounted for this association, and asymmetric you-talk contributed independently as well. In contrast to previous studies of we-talk by individual partners, the present results identify dyad-level pronoun patterns that clearly do not mark beneficent processes: asymmetric partner we/I-ratios and you-talk reflect problematic demand-withdraw interaction. PMID:24098961
A vorticity based approach to handle the fluid-structure interaction problems
Energy Technology Data Exchange (ETDEWEB)
Farahbakhsh, Iman; Ghassemi, Hassan [Department of Ocean Engineering, Amirkabir University of Technology, Tehran (Iran, Islamic Republic of); Sabetghadam, Fereidoun, E-mail: i.farahbakhsh@aut.ac.ir [Mechanical and Aerospace Engineering Department, Science and Research Branch, Islamic Azad University (IAU), Tehran (Iran, Islamic Republic of)
2016-02-15
A vorticity based approach for the numerical solution of the fluid-structure interaction problems is introduced in which the fluid and structure(s) can be viewed as a continuum. Retrieving the vorticity field and recalculating a solenoidal velocity field, specially at the fluid-structure interface, are the kernel of the proposed algorithm. In the suggested method, a variety of constitutive equations as a function of left Cauchy–Green deformation tensor can be applied for modeling the structure domain. A nonlinear Mooney–Rivlin and Saint Venant–Kirchhoff model are expressed in terms of the left Cauchy–Green deformation tensor and the presented method is able to model the behavior of a visco-hyperelastic structure in the incompressible flow. Some numerical experiments, with considering the neo-Hookean model for structure domain, are executed and the results are validated via the available results from literature. (paper)
Directory of Open Access Journals (Sweden)
Chernova, N.A.
2018-03-01
Full Text Available The article deals with the concept of a continuum of regulation being also important to understanding Vygotsky’s view of cognitive development which clearly suggests that communicative collaboration with adults or more skilled peers contributes to the development of self-regulation, that is, the capacity for independent problem solving and self-directed activity. Attention is drawn to the fact that in the language classroom, using sociocultural theory and its tenets as a framework, we would see a highly interactive classroom, where the students’ zone of proximal development is identified through strategies such as portfolios, and dialogue journals. Necessity of compiling a textbook based on the above-mentioned principles is stressed.
Lunkenheimer, Erika S.; Albrecht, Erin C.; Kemp, Christine J.
2013-01-01
Lower levels of parent-child affective flexibility indicate risk for children's problem outcomes. This short-term longitudinal study examined whether maternal depressive symptoms were related to lower levels of dyadic affective flexibility and positive affective content in mother-child problem-solving interactions at age 3.5?years…
Leckman-Westin, Emily; Cohen, Patricia R.; Stueve, Ann
2009-01-01
Objective: Increased behavior problems have been reported in offspring of mothers with depression. In-home observations link maternal depressive symptoms (MDS) and mother-child interaction patterns with toddler behavior problems and examine their persistence into late childhood. Method: Maternal characteristics (N = 153) and behaviors of…
Spoth, Richard; Neppl, Tricia; Goldberg-Lillehoj, Catherine; Jung, Tony; Ramisetty-Mikler, Suhasini
2006-01-01
This article reports two exploratory studies testing a model guided by a social interactional perspective, positing an inverse relation between the quality of parent-child interactions and adolescent problem behaviors. It addresses mixed findings in the literature related to gender differences. Study 1 uses cross-sectional survey data from…
Kuijpers, R.C.W.M.; Otten, R.; Krol, N.P.C.M.; Vermulst, A.A.; Engels, R.C.M.E.
2013-01-01
Children and youths' self-report of mental health problems is considered essential but complicated. This study examines the psychometric properties of the Dominic Interactive, a computerized DSM-IV based self-report questionnaire and explores informant correspondence. The Dominic Interactive was
Rhodes, Jessica D; Colder, Craig R; Trucco, Elisa M; Speidel, Carolyn; Hawk, Larry W; Lengua, Liliana J; Das Eiden, Rina; Wieczorek, William
2013-01-01
A large literature suggests associations between self-regulation and motivation and adolescent problem behavior; however, this research has mostly pitted these constructs against one another or tested them in isolation. Following recent neural-systems based theories (e.g., Ernst & Fudge, 2009 ), the present study investigated the interactions between self-regulation and approach and avoidance motivation prospectively predicting delinquency and depressive symptoms in early adolescence. The community sample included 387 adolescents aged 11 to 13 years old (55% female; 17% minority). Laboratory tasks were used to assess self-regulation and approach and avoidance motivation, and adolescent self-reports were used to measure depressive symptoms and delinquency. Analyses suggested that low levels of approach motivation were associated with high levels of depressive symptoms, but only at high levels of self-regulation (p = .01). High levels of approach were associated with high levels of rule breaking, but only at low levels of self-regulation (p theories that posit integration of motivational and self-regulatory individual differences via moderational models to understand adolescent problem behavior.
Directory of Open Access Journals (Sweden)
ADA ZHENG
2011-10-01
Full Text Available We have developed an innovative hybrid problem-based learning (PBL methodology. The methodology has the following distinctive features: i Each complex question was decomposed into a set of coherent finer subquestions by following the carefully designed criteria to maintain a delicate balance between guiding the students and inspiring them to think independently. This learning methodology enabled the students to solve the complex questions progressively in an inductive context. ii Facilitated by the utilization of our web-based learning systems, the teacher was able to interact with the students intensively and could allocate more teaching time to provide tailor-made feedback for individual student. The students were actively engaged in the learning activities, stimulated by the intensive interaction. iii The answers submitted by the students could be automatically consolidated in the report of the Moodle system in real-time. The teacher could adjust the teaching schedule and focus of the class to adapt to the learning progress of the students by analysing the automatically generated report and log files of the web-based learning system. As a result, the attendance rate of the students increased from about 50% to more than 90%, and the students’ learning motivation have been significantly enhanced.
Interactive dualism as a partial solution to the mind-brain problem for psychiatry.
McLaren, N
2006-01-01
With the collapse of the psychoanalytic and the behaviorist models, and the failure of reductive biologism to account for mental life, psychiatry has been searching for a broad, integrative theory on which to base daily practice. The most recent attempt at such a model, Engel's 'biopsychosocial model', has been shown to be devoid of any scientific content, meaning that psychiatry, alone among the medical disciplines, has no recognised scientific basis. It is no coincidence that psychiatry is constantly under attack from all quarters. In order to develop, the discipline requires an integrative and interactive model which can take account of both the mental and the physical dimensions of human life, yet still remain within the materialist scientific ethos. This paper proposes an entirely new model of mind based in Chalmers' 'interactive dualism' which satisfies those needs. It attributes the causation of all behaviour to mental life, but proposes a split in the nature of mentality such that mind becomes a composite function with two, profoundly different aspects. Causation is assigned to a fast, inaccessible cognitive realm operating within the brain machinery while conscious experience is seen as the outcome of a higher order level of brain processing. The particular value of this model is that it immediately offers a practical solution to the mind-brain problem in that, while all information-processing takes place in the mental realm, it is not in the same order of abstraction as perception. This leads to a model of rational interaction which acknowledges both psyche and soma. It can fill the gap left by the demise of Engel's empty 'biopsychosocial model'.
Kim, C.
2012-01-01
Over the last decade consumer electronic product industries have been confronted with an increase in consumer complaints. Interestingly about half of the reasons for product return are based on so called ‘soft problems’, consumer complaints that cannot be traced back to technical problems. Probably
Najmi, Sadia; Bureau, Jean-Francois; Chen, Diyu; Lyons-Ruth, Karlen
2009-12-01
: The Personal Attitude Scale (PAS; Hooley, 2000) is a method that is under development for identifying individuals high in Expressed Emotion based on personality traits of inflexibility, intolerance, and norm-forming. In the current study, the goal was to measure the association between this maternal attitudinal inflexibility, early hostile or disrupted mother-infant interactions, and hostile-aggressive behavior problems in the child. In a prospective longitudinal study of 76 low-income mothers and their infants, it was predicted that maternal PAS scores, assessed at child age 20, would be related to difficulties in early observed mother-infant interaction and to hostile-aggressive behavioral difficulties in the child. Results indicated that maternal difficulties in interacting with the infant in the laboratory were associated with maternal PAS scores assessed 20 years later. Hostile-aggressive behavior problems in the child at age five were also predictive of PAS scores of mothers. However, contrary to prediction, these behavior problems did not mediate the association between mother-infant interaction difficulties and maternal PAS scores, indicating that the child's hostile-aggressive behavior problems did not produce the link between quality of early interaction and later maternal attitudinal inflexibility. The current results validate the PAS against observable mother-child interactions and child hostile-aggressive behavior problems and indicate the importance of future work investigating the maternal attitudes that are associated with, and may potentially precede, parent-infant interactive difficulties. These findings regarding the inflexible attitudes of mothers whose interactions with their infants are also disrupted have important clinical implications. First, once the stability of the PAS has been established, this measure may offer a valuable screening tool for the prenatal identification of parents at risk for difficult interactions with their children
Lengua, L J; Wolchik, S A; Sandler, I N; West, S G
2000-06-01
Investigated the interaction between parenting and temperament in predicting adjustment problems in children of divorce. The study utilized a sample of 231 mothers and children, 9 to 12 years old, who had experienced divorce within the previous 2 years. Both mothers' and children's reports on parenting, temperament, and adjustment variables were obtained and combined to create cross-reporter measures of the variables. Parenting and temperament were directly and independently related to outcomes consistent with an additive model of their effects. Significant interactions indicated that parental rejection was more strongly related to adjustment problems for children low in positive emotionality, and inconsistent discipline was more strongly related to adjustment problems for children high in impulsivity. These findings suggest that children who are high in impulsivity may be at greater risk for developing problems, whereas positive emotionality may operate as a protective factor, decreasing the risk of adjustment problems in response to negative parenting.
International Nuclear Information System (INIS)
Supasorn, Saksri; Vibuljun, Sunantha; Panijpan, Bhinyo; Rajviroongit, Shuleewan
2005-10-01
An Interactive Web-Based Learning NMR Spectroscopy course is developed to improve and facilitate student ' s learning as well as achievement of learning objectives in the concepts of multiplicity, chemical shift, and problem solving. This web-based learning course is emphasized on NMR problem solving, therefore, the concepts of multiplicity and chemical shift, basic concepts for practice problem solving, are also emphasized. Most of animations and pictures in this web-based learning are new created and simplified to explain processes and principles in NMR spectroscopy. With meaningful animations and pictures, simplified English language used, step-by-step problem solving, and interactive test, it can be self-learning web site and best on the student ' s convenience
International Nuclear Information System (INIS)
Chang, Y.W.; Chu, H.Y.; Gvildys, J.; Wang, C.Y.
1979-01-01
The analysis of fluid-structure interaction involves the calculation of both fluid transient and structure dynamics. In the structural analysis, Lagrangian meshes have been used exclusively, whereas for the fluid transient, Lagrangian, Eulerian, and arbitrary Lagrangian-Eulerian (quasi-Eulerian) meshes have been used. This paper performs an evaluation on these three types of meshes. The emphasis is placed on the applicability of the method in analyzing fluid-structure interaction problems in HCDA analysis
Quantum Monte Carlo simulations of the Fermi-polaron problem and bosons with Gaussian interactions
Energy Technology Data Exchange (ETDEWEB)
Kroiss, Peter Michael
2017-02-01
This thesis deals with the application of current Quantum Monte Carlo algorithms to many-body systems of fermionic and bosonic species. The first part applies the diagrammatic Monte Carlo method to the Fermi polaron problem, a system of an impurity interacting resonantly with a homogeneous Fermi bath. It is numerically shown that the three particle-hole diagrams do not contribute significantly to the final answer in a quasi-two-dimensional setup, thus demonstrating a nearly perfect destructive interference of contributions in subspaces with higher-order particle-hole lines. Consequently, for strong-enough confinement in the third direction, the transition between the polaron and the molecule ground state is found to be in good agreement with the pure two-dimensional case and agrees very well with the one found by the wave-function approach in the two-particle-hole subspace. In three-dimensional Fermi-polaron systems with mass imbalance of impurity and bath atoms, polaron energy and quasiparticle residue can be accurately determined over a broad range of impurity masses. Furthermore, the spectral function of an imbalanced polaron demonstrates the stability of the quasiparticle and also allows us to locate the repulsive polaron as an excited state. The quantitative exactness of two-particle-hole wave functions is investigated, resulting in a relative lowering of polaronic energies in the mass-imbalance phase diagram. Tan's contact coefficient for the mass-balanced polaron system is found to be in good agreement with variational methods. Mass-imbalanced systems can be studied experimentally by ultracold atom mixtures such as {sup 6}Li-{sup 40}K. In the second part of the thesis, the ground state of a two-dimensional system of Bose particles of spin zero, interacting via a repulsive Gaussian-Core potential, is investigated by means of path integral Monte Carlo simulations. The quantum phase diagram is qualitatively identical to that of two-dimensional Yukawa
Mkhitaryan, S. M.
2018-04-01
A class of mixed boundary-value problems of mathematical theory of elasticity dealing with interaction between stress concentrators of different types (such as cracks, absolutely rigid thin inclusions, punches, and stringers) and an elastic semi-infinite plate is considered. The method of Mellin integral transformation is used to reduce solving these problems to solving singular integral equations (SIE). After the governing SIE are solved, the following characteristics of the problem are determined: tangential contact stresses under stringers, dislocation density on the crack edges, breaking stresses outside the cracks on their line of location, the stress intensity factor (SIF), crack openings, jumps of contact stresses on the edges of inclusions.
Dubois-Comtois, Karine; Moss, Ellen; Cyr, Chantal; Pascuzzo, Katherine
2013-11-01
The objective of the study was to examine the longitudinal relation between early school-age measures of maternal psychosocial distress, quality of mother-child interactions, and child attachment behavior, and behavior problem profiles in middle childhood using a multi-informant design. Participants were 243 French-speaking mother-child dyads (122 girls) who were part of an ongoing longitudinal project. Maternal psychosocial distress was assessed when children were between 4 and 6 years of age. Mother-child interactive quality and attachment patterns were observed at age 6 during a laboratory visit. At age 8.5, externalizing and internalizing problems were assessed using mother and child reports. Results show that maternal psychosocial distress predicted later social adaptation reported by the child through the mediation of mother-child interactions. Analyses also revealed that higher maternal psychosocial distress and controlling attachment patterns, either of the punitive or caregiving type, significantly predicted membership in both child internalizing and externalizing clinical problem groups. Lower mother-child interactive quality, male gender, and child ambivalent attachment were also predictors of externalizing clinical problems.
CSIR Research Space (South Africa)
Suliman, Ridhwaan
2015-01-01
Full Text Available . The solver is parallelised for distributed-memory systems using METIS for domaindecomposition and MPI for inter-domain communication. The developed technology is evaluated by application to benchmark problems for strongly-coupled fluid-structure interaction...
Kumar, David Devraj
2017-01-01
This paper reports an analysis of an interactive technology-supported, problem-based learning (PBL) project in science, technology, engineering and mathematics (STEM) from a Learning Sciences perspective using the Selected Learning Sciences Interest Areas (SLSIA). The SLSIA was adapted from the "What kinds of topics do ISLS [International…
DEFF Research Database (Denmark)
Silcowitz, Morten; Niebe, Sarah Maria; Erleben, Kenny
2009-01-01
contact response. In this paper, we present a new approach to contact force determination. We reformulate the contact force problem as a nonlinear root search problem, using a Fischer function. We solve this problem using a generalized Newton method. Our new Fischer - Newton method shows improved...... qualities for specific configurations where the most widespread alternative, the Projected Gauss-Seidel method, fails. Experiments show superior convergence properties of the exact Fischer - Newton method....
Nonlinear localized excitations in magnets with a weak exchange interaction as a soliton problem
International Nuclear Information System (INIS)
Gvozdikova, M.V.; Kovalev, A.S.
1998-01-01
The spin dynamics of soliton-like localized excitations in a discrete ferromagnet chain with an easy axis anisotropy and a weak exchange interaction is studied. The connection of these excitations with longwave magnetic solitons is discussed. The localized excitation frequency dependence on exchange interaction is found for a fixed number of spin deviation. It is shown that this dependence modifies essentially when the exchange interaction becomes comparable with an anisotropy value
Directory of Open Access Journals (Sweden)
Jaime S. Ide
2017-01-01
Full Text Available Alcohol expectancy and impulsivity are implicated in alcohol misuse. However, how these two risk factors interact to determine problem drinking and whether men and women differ in these risk processes remain unclear. In 158 social drinkers (86 women assessed for Alcohol Use Disorder Identification Test (AUDIT, positive alcohol expectancy, and Barratt impulsivity, we examined sex differences in these risk processes. Further, with structural brain imaging, we examined the neural bases underlying the relationship between these risk factors and problem drinking. The results of general linear modeling showed that alcohol expectancy best predicted problem drinking in women, whereas in men as well as in the combined group alcohol expectancy and impulsivity interacted to best predict problem drinking. Alcohol expectancy was associated with decreased gray matter volume (GMV of the right posterior insula in women and the interaction of alcohol expectancy and impulsivity was associated with decreased GMV of the left thalamus in women and men combined and in men alone, albeit less significantly. These risk factors mediated the correlation between GMV and problem drinking. Conversely, models where GMV resulted from problem drinking were not supported. These new findings reveal distinct psychological factors that dispose men and women to problem drinking. Although mediation analyses did not determine a causal link, GMV reduction in the insula and thalamus may represent neural phenotype of these risk processes rather than the consequence of alcohol consumption in non-dependent social drinkers. The results add to the alcohol imaging literature which has largely focused on dependent individuals and help elucidate alterations in brain structures that may contribute to the transition from social to habitual drinking.
Ide, Jaime S; Zhornitsky, Simon; Hu, Sien; Zhang, Sheng; Krystal, John H; Li, Chiang-Shan R
2017-01-01
Alcohol expectancy and impulsivity are implicated in alcohol misuse. However, how these two risk factors interact to determine problem drinking and whether men and women differ in these risk processes remain unclear. In 158 social drinkers (86 women) assessed for Alcohol Use Disorder Identification Test (AUDIT), positive alcohol expectancy, and Barratt impulsivity, we examined sex differences in these risk processes. Further, with structural brain imaging, we examined the neural bases underlying the relationship between these risk factors and problem drinking. The results of general linear modeling showed that alcohol expectancy best predicted problem drinking in women, whereas in men as well as in the combined group alcohol expectancy and impulsivity interacted to best predict problem drinking. Alcohol expectancy was associated with decreased gray matter volume (GMV) of the right posterior insula in women and the interaction of alcohol expectancy and impulsivity was associated with decreased GMV of the left thalamus in women and men combined and in men alone, albeit less significantly. These risk factors mediated the correlation between GMV and problem drinking. Conversely, models where GMV resulted from problem drinking were not supported. These new findings reveal distinct psychological factors that dispose men and women to problem drinking. Although mediation analyses did not determine a causal link, GMV reduction in the insula and thalamus may represent neural phenotype of these risk processes rather than the consequence of alcohol consumption in non-dependent social drinkers. The results add to the alcohol imaging literature which has largely focused on dependent individuals and help elucidate alterations in brain structures that may contribute to the transition from social to habitual drinking.
Siqveland, Torill S; Haabrekke, Kristin; Wentzel-Larsen, Tore; Moe, Vibeke
2014-11-01
The aim of this study was to investigate the development of mother-infant interaction patterns from 3 to 12 months among three groups of mother-baby pairs recruited during pregnancy: one group from residential substance abuse treatment (n=28), a second group from psychiatric outpatient treatment (n=22), and a third group from well-baby clinics (n=30). The mother-infant interaction at 3 and 12 months was assessed by the Parent-Child Early Relational Assessment (PCERA), which consists of maternal, child and dyadic subscales (Clark, 2006). Linear mixed effects models were used to analyze group differences and the changes in mother-infant interaction from 3 to 12 months. At 3 months, pairwise comparisons showed that the group with psychiatric problems had significantly more difficulties in the mother-infant interaction than the two other groups. The group with substance abuse problems was not significantly different from the two other groups. At 12 months, the mother-infant pairs in the substance abuse group showed significantly more relational disturbances than the non-clinical pairs, as well as a poorer affective quality of interaction than the dyads in the group with psychiatric problems. Analysis of change from 3 to 12 months showed that difficulties in the interaction increased among the mother-baby pairs in the substance abuse group, while improvements were displayed in the two other groups. These results underline that mother-infant pairs at double risk due to maternal substance abuse and other non-optimal factors, are in need for long-term follow up in order to prevent the development of negative interactional patterns. Copyright © 2014 Elsevier Inc. All rights reserved.
Childhood problem behavior and parental divorce: evidence for gene–environment interaction
Robbers, S.C.C.; van Oort, F.V.; Huizink, A.C.; Verhulst, F.C.; van Beijsterveldt, C.E.M.; Boomsma, D.I.; Bartels, M.
2012-01-01
Objective: The importance of genetic and environmental influences on children's behavioral and emotional problems may vary as a function of environmental exposure. We previously reported that 12-year-olds with divorced parents showed more internalizing and externalizing problems than children with
Childhood problem behavior and parental divorce: evidence for gene-environment interaction
S.C.C. Robbers (Sylvana); F.V.A. van Oort (Floor); A.C. Huizink (Anja); F.C. Verhulst (Frank); C.E.M. van Beijsterveldt (Toos); D.I. Boomsma (Dorret); M. Bartels (Meike)
2012-01-01
textabstractObjective: The importance of genetic and environmental influences on children's behavioral and emotional problems may vary as a function of environmental exposure. We previously reported that 12-year-olds with divorced parents showed more internalizing and externalizing problems than
A Real-Life Case Study of Audit Interactions--Resolving Messy, Complex Problems
Beattie, Vivien; Fearnley, Stella; Hines, Tony
2012-01-01
Real-life accounting and auditing problems are often complex and messy, requiring the synthesis of technical knowledge in addition to the application of generic skills. To help students acquire the necessary skills to deal with these problems effectively, educators have called for the use of case-based methods. Cases based on real situations (such…
Thai, Khanh-Phuong; Son, Ji Y.; Hoffman, Jessica; Devers, Christopher; Kellman, Philip J.
2014-01-01
Mathematics is the study of structure but students think of math as solving problems according to rules. Students can learn procedures, but they often have trouble knowing when to apply learned procedures, especially to problems unlike those they trained with. In this study, the authors rely on the psychological mechanism of perceptual learning…
Directory of Open Access Journals (Sweden)
Marisa ePrzyrembel
2012-06-01
Full Text Available Successful human social interaction depends on our capacity to understand other people’s mental states and to anticipate how they will react to our actions. Despites its importance to the human condition, there are still quite a few debates about how we actually solve the problem of understanding other peoples’ actions, feelings and thoughts. Here we consider this problem from philosophical, psychological, and neuroscientific perspectives. In a critical review we show that attempts to draw parallels across these complementary levels of analysis are premature: The second-person perspective does not map directly to simulation theories, online social cognition or shared neural networks underlying action observation or empathy. Nor does the third-person perspective map onto theory-theory accounts of other agents mental states, offline social cognition or the neural networks that support Theory of Mind. We further propose that important qualities of social interaction emerge through the reciprocal interaction of two independent agents whose unpredictable behaviour requires a continual updating of models of their partner internal state. This analysis draws attention to the need for paradigms that allow two individuals to interact in a spontaneous and natural manner and to adapt their behaviour and cognitions in a response contingent fashion due to the unpredictability of their partners behaviour. Even if such paradigms were implemented, it is possible that the specific neural correlates supporting such reciprocal interaction would not reflect the processes unique to social interaction because much real social behaviour may reflect the use of basic cognitive and emotional process in a novel and unique manner. Given the role of social interaction in human evolution, ontogeny and every-day social life, a more theoretically and methodologically nuanced approach to the study of social interaction will help to shed new light on the dark matter of social
Abrahamse, Mariëlle E.; Junger, Marianne; Chavannes, E. Lidewei; Coelman, Frederique J. G.; Boer, Frits; Lindauer, Ramón J. L.
2012-01-01
ABSTRACT: BACKGROUND: Persistent high levels of aggressive, oppositional and impulsive behaviours, in the early lives of children, are significant risk factors for adolescent and adult antisocial behaviour and criminal activity. If the disruptive behavioural problems of young children could be
Archambeault, Betty
1993-01-01
Holistic math focuses on problem solving with numbers and concepts. Whole math activities for adults include shopping for groceries, eating in restaurants, buying gas, taking medicine, measuring a room, estimating servings, and compiling a family cookbook. (SK)
A nonsmooth nonlinear conjugate gradient method for interactive contact force problems
DEFF Research Database (Denmark)
Silcowitz, Morten; Abel, Sarah Maria Niebe; Erleben, Kenny
2010-01-01
of a nonlinear complementarity problem (NCP), which can be solved using an iterative splitting method, such as the projected Gauss–Seidel (PGS) method. We present a novel method for solving the NCP problem by applying a Fletcher–Reeves type nonlinear nonsmooth conjugate gradient (NNCG) type method. We analyze...... and present experimental convergence behavior and properties of the new method. Our results show that the NNCG method has at least the same convergence rate as PGS, and in many cases better....
International Nuclear Information System (INIS)
Matthees, W.; Magiera, G.
1982-01-01
A sensitivity study for the interaction effects of adjacent structures of nuclear power plants caused by horizontal seismic excitation has been performed. The key structural and soil parameters for linear and for nonlinear behaviour were varied within their applicable bandwidth. It has been shown that the interaction phenomena can contribute to the response of structures to such a large extent that it cannot be disregarded. (orig.)
Tsai, Alexander C; Burns, Bridget F O
2015-08-01
In the theory of syndemics, diseases co-occur in particular temporal or geographical contexts due to harmful social conditions (disease concentration) and interact at the level of populations and individuals, with mutually enhancing deleterious consequences for health (disease interaction). This theory has widespread adherents in the field, but the extent to which there is empirical support for the concept of disease interaction remains unclear. In January 2015 we systematically searched 7 bibliographic databases and tracked citations to highly cited publications associated with the theory of syndemics. Of the 783 records, we ultimately included 34 published journal articles, 5 dissertations, and 1 conference abstract. Most studies were based on a cross-sectional design (32 [80%]), were conducted in the U.S. (32 [80%]), and focused on men who have sex with men (21 [53%]). The most frequently studied psychosocial problems were related to mental health (33 [83%]), substance abuse (36 [90%]), and violence (27 [68%]); while the most frequently studied outcome variables were HIV transmission risk behaviors (29 [73%]) or HIV infection (9 [23%]). To test the disease interaction concept, 11 (28%) studies used some variation of a product term, with less than half of these (5/11 [45%]) providing sufficient information to interpret interaction both on an additive and on a multiplicative scale. The most frequently used specification (31 [78%]) to test the disease interaction concept was the sum score corresponding to the total count of psychosocial problems. Although the count variable approach does not test hypotheses about interactions between psychosocial problems, these studies were much more likely than others (14/31 [45%] vs. 0/9 [0%]; χ2 = 6.25, P = 0.01) to incorporate language about "synergy" or "interaction" that was inconsistent with the statistical models used. Therefore, more evidence is needed to assess the extent to which diseases interact, either at the
Neilson, Peter D; Neilson, Megan D
2005-09-01
Adaptive model theory (AMT) is a computational theory that addresses the difficult control problem posed by the musculoskeletal system in interaction with the environment. It proposes that the nervous system creates motor maps and task-dependent synergies to solve the problems of redundancy and limited central resources. These lead to the adaptive formation of task-dependent feedback/feedforward controllers able to generate stable, noninteractive control and render nonlinear interactions unobservable in sensory-motor relationships. AMT offers a unified account of how the nervous system might achieve these solutions by forming internal models. This is presented as the design of a simulator consisting of neural adaptive filters based on cerebellar circuitry. It incorporates a new network module that adaptively models (in real time) nonlinear relationships between inputs with changing and uncertain spectral and amplitude probability density functions as is the case for sensory and motor signals.
Przyrembel, Marisa; Smallwood, Jonathan; Pauen, Michael; Singer, Tania
2012-01-01
Successful human social interaction depends on our capacity to understand other people's mental states and to anticipate how they will react to our actions. Despite its importance to the human condition, the exact mechanisms underlying our ability to understand another's actions, feelings, and thoughts are still a matter of conjecture. Here, we consider this problem from philosophical, psychological, and neuroscientific perspectives. In a critical review, we demonstrate that attempts to draw ...
Niec, Larissa N; Barnett, Miya L; Prewett, Matthew S; Shanley Chatham, Jenelle R
2016-08-01
Although efficacious interventions exist for childhood conduct problems, a majority of families in need of services do not receive them. To address problems of treatment access and adherence, innovative adaptations of current interventions are needed. This randomized control trial investigated the relative efficacy of a novel format of parent-child interaction therapy (PCIT), a treatment for young children with conduct problems. Eighty-one families with 3- to 6-year-old children (71.6% boys, 85.2% White) with diagnoses of oppositional defiant or conduct disorder were randomized to individual PCIT (n = 42) or the novel format, Group PCIT. Parents completed standardized measures of children's conduct problems, parenting stress, and social support at intake, posttreatment, and 6-month follow-up. Therapist ratings, parent attendance, and homework completion provided measures of treatment adherence. Throughout treatment, parenting skills were assessed using the Dyadic Parent-Child Interaction Coding System. Parents in both group and individual PCIT reported significant improvements from intake to posttreatment and follow-up in their children's conduct problems and adaptive functioning, as well as significant decreases in parenting stress. Parents in both treatment conditions also showed significant improvements in their parenting skills. There were no interactions between time and treatment format. Contrary to expectation, parents in Group PCIT did not experience greater social support or treatment adherence. Group PCIT was not inferior to individual PCIT and may be a valuable format to reach more families in need of services. Future work should explore the efficiency and sustainability of Group PCIT in community settings. (PsycINFO Database Record (c) 2016 APA, all rights reserved).
Niec, Larissa N.; Barnett, Miya L.; Prewett, Matthew S.; Shanley, Jenelle
2016-01-01
Objective Although efficacious interventions exist for childhood conduct problems, a majority of families in need of services do not receive them. To address problems of treatment access and adherence, innovative adaptations of current interventions are needed. This randomized control trial investigated the relative efficacy of a novel format of parent-child interaction therapy (PCIT), a treatment for young children with conduct problems. Methods Eighty-one families with three- to six-year-old children (71.6% male; 85.2% Caucasian) with diagnoses of oppositional defiant or conduct disorder were randomized to individual PCIT (n = 42) or the novel format, group PCIT. Parents completed standardized measures of children’s conduct problems, parenting stress, and social support at intake, posttreatment, and six-month follow-up. Therapist ratings, parent attendance, and homework completion provided measures of treatment adherence. Throughout treatment, parenting skills were assessed using the Dyadic Parent-Child Interaction Coding System. Results Parents in both group and individual PCIT reported significant improvements from intake to posttreatment and follow-up in their children’s conduct problems and adaptive functioning, as well as significant decreases in parenting stress. Parents in both treatment conditions also showed significant improvements in their parenting skills. There were no interactions between time and treatment format. Contrary to expectation, parents in group PCIT did not experience greater social support or treatment adherence. Conclusions Group PCIT was not inferior to individual PCIT and may be a valuable format to reach more families in need of services. Future work should explore the efficiency and sustainability of group PCIT in community settings. PMID:27018531
Reader, Arran T; Holmes, Nicholas P
2016-01-01
Social interaction is an essential part of the human experience, and much work has been done to study it. However, several common approaches to examining social interactions in psychological research may inadvertently either unnaturally constrain the observed behaviour by causing it to deviate from naturalistic performance, or introduce unwanted sources of variance. In particular, these sources are the differences between naturalistic and experimental behaviour that occur from changes in visual fidelity (quality of the observed stimuli), gaze (whether it is controlled for in the stimuli), and social potential (potential for the stimuli to provide actual interaction). We expand on these possible sources of extraneous variance and why they may be important. We review the ways in which experimenters have developed novel designs to remove these sources of extraneous variance. New experimental designs using a 'two-person' approach are argued to be one of the most effective ways to develop more ecologically valid measures of social interaction, and we suggest that future work on social interaction should use these designs wherever possible.
Directory of Open Access Journals (Sweden)
Irena Schneiderová
Full Text Available Shrews have rich vocal repertoires that include vocalizations within the human audible frequency range and ultrasonic vocalizations. Here, we recorded and analyzed in detail the acoustic structure of a vocalization with unclear functional significance that was spontaneously produced by 15 adult, captive Asian house shrews (Suncus murinus while they were lying motionless and resting in their nests. This vocalization was usually emitted repeatedly in a long series with regular intervals. It showed some structural variability; however, the shrews most frequently emitted a tonal, low-frequency vocalization with minimal frequency modulation and a low, non-vocal click that was clearly noticeable at its beginning. There was no effect of sex, but the acoustic structure of the analyzed vocalizations differed significantly between individual shrews. The encoded individuality was low, but it cannot be excluded that this individuality would allow discrimination of family members, i.e., a male and female with their young, collectively resting in a common nest. The question remains whether the Asian house shrews indeed perceive the presence of their mates, parents or young resting in a common nest via the resting-associated vocalization and whether they use it to discriminate among their family members. Additional studies are needed to explain the possible functional significance of resting-associated vocalizations emitted by captive Asian house shrews. Our study highlights that the acoustic communication of shrews is a relatively understudied topic, particularly considering that they are highly vocal mammals.
Zhu, Zheng; Andresen, Juan Carlos; Moore, M. A.; Katzgraber, Helmut G.
2014-02-01
We study the equilibrium and nonequilibrium properties of Boolean decision problems with competing interactions on scale-free networks in an external bias (magnetic field). Previous studies at zero field have shown a remarkable equilibrium stability of Boolean variables (Ising spins) with competing interactions (spin glasses) on scale-free networks. When the exponent that describes the power-law decay of the connectivity of the network is strictly larger than 3, the system undergoes a spin-glass transition. However, when the exponent is equal to or less than 3, the glass phase is stable for all temperatures. First, we perform finite-temperature Monte Carlo simulations in a field to test the robustness of the spin-glass phase and show that the system has a spin-glass phase in a field, i.e., exhibits a de Almeida-Thouless line. Furthermore, we study avalanche distributions when the system is driven by a field at zero temperature to test if the system displays self-organized criticality. Numerical results suggest that avalanches (damage) can spread across the whole system with nonzero probability when the decay exponent of the interaction degree is less than or equal to 2, i.e., that Boolean decision problems on scale-free networks with competing interactions can be fragile when not in thermal equilibrium.
Puliafico, Anthony C.; Kurtz, Steven M. S.; Pincus, Donna B.; Comer, Jonathan S.
2014-01-01
Although efficacious psychological treatments for internalizing disorders are now well established for school-aged children, until recently there have regrettably been limited empirical efforts to clarify indicated psychological intervention methods for the treatment of mood and anxiety disorders presenting in early childhood. Young children lack many of the developmental capacities required to effectively participate in established treatments for mood and anxiety problems presenting in older children, making simple downward extensions of these treatments for the management of preschool internalizing problems misguided. In recent years, a number of research groups have successfully adapted and modified parent–child interaction therapy (PCIT), originally developed to treat externalizing problems in young children, to treat various early internalizing problems with a set of neighboring protocols. As in traditional PCIT, these extensions target child symptoms by directly reshaping parent–child interaction patterns associated with the maintenance of symptoms. The present review outlines this emerging set of novel PCIT adaptations and modifications for mood and anxiety problems in young children and reviews preliminary evidence supporting their use. Specifically, we cover (a) PCIT for early separation anxiety disorder; (b) the PCIT-CALM (Coaching Approach behavior and Leading by Modeling) Program for the full range of early anxiety disorders; (c) the group Turtle Program for behavioral inhibition; and (d) the PCIT-ED (Emotional Development) Program for preschool depression. In addition, emerging PCIT-related protocols in need of empirical attention—such as the PCIT-SM (selective mutism) Program for young children with SM—are also considered. Implications of these protocols are discussed with regard to their unique potential to address the clinical needs of young children with internalizing problems. Obstacles to broad dissemination are addressed, and we consider
Carpenter, Aubrey L; Puliafico, Anthony C; Kurtz, Steven M S; Pincus, Donna B; Comer, Jonathan S
2014-12-01
Although efficacious psychological treatments for internalizing disorders are now well established for school-aged children, until recently there have regrettably been limited empirical efforts to clarify indicated psychological intervention methods for the treatment of mood and anxiety disorders presenting in early childhood. Young children lack many of the developmental capacities required to effectively participate in established treatments for mood and anxiety problems presenting in older children, making simple downward extensions of these treatments for the management of preschool internalizing problems misguided. In recent years, a number of research groups have successfully adapted and modified parent-child interaction therapy (PCIT), originally developed to treat externalizing problems in young children, to treat various early internalizing problems with a set of neighboring protocols. As in traditional PCIT, these extensions target child symptoms by directly reshaping parent-child interaction patterns associated with the maintenance of symptoms. The present review outlines this emerging set of novel PCIT adaptations and modifications for mood and anxiety problems in young children and reviews preliminary evidence supporting their use. Specifically, we cover (a) PCIT for early separation anxiety disorder; (b) the PCIT-CALM (Coaching Approach behavior and Leading by Modeling) Program for the full range of early anxiety disorders; (c) the group Turtle Program for behavioral inhibition; and (d) the PCIT-ED (Emotional Development) Program for preschool depression. In addition, emerging PCIT-related protocols in need of empirical attention--such as the PCIT-SM (selective mutism) Program for young children with SM--are also considered. Implications of these protocols are discussed with regard to their unique potential to address the clinical needs of young children with internalizing problems. Obstacles to broad dissemination are addressed, and we consider
Burt, Keith B.; Paysnick, Amy A.
2014-01-01
The present study examined sense of identity (assessed using the Identity subscale of the Psychosocial Maturity Inventory) as a moderator of associations between stressful life events, behavioral/emotional problems, and substance abuse in a sample of 187 college undergraduates (67% female). Correlations showed evidence for positive associations…
Use of the finite element displacement method to solve solid-fluid interaction vibration problems
International Nuclear Information System (INIS)
Brown, S.J.; Hsu, K.H.
1978-01-01
It is shown through comparison to experimental, theoretical, and other finite element formulations that the finite element displacement method can solve accurately and economically a certain class of solid-fluid eigenvalue problems. The problems considered are small displacements in the absence of viscous damping and are 2-D and 3-D in nature. In this study the advantages of the finite element method (in particular the displacement formulation) is apparent in that a large structure consisting of the cylinders, support flanges, fluid, and other experimental boundaries could be modeled to yield good correlation to experimental data. The ability to handle large problems with standard structural programs is the key advantage of the displacement fluid method. The greatest obstacle is the inability of the analyst to inhibit those rotational degrees of freedom that are unnecessary to his fluid-structure vibration problem. With judicious use of element formulation, boundary conditions and modeling, the displacement finite element method can be successfully used to predict solid-fluid response to vibration and seismic loading
Abrahamse, Mariëlle; Junger, Marianne; Chavannes, E.L.; Coelman, F.J.G.; de Boer, F.; Lindauer, R.J.
2012-01-01
Background Persistent high levels of aggressive, oppositional and impulsive behaviours, in the early lives of children, are significant risk factors for adolescent and adult antisocial behaviour and criminal activity. If the disruptive behavioural problems of young children could be prevented or
Directory of Open Access Journals (Sweden)
Boris A. Arbuzov
2017-11-01
Full Text Available Wouldbe consequences of the existence of effective interactions in quantum gravitation theory are considered. In the framework of the approach, the example of a running gravitational coupling is presented, corresponding to an adequate description of effects, which nowadays are usually prescribed to dark matter and dark energy.
Seven-step problem-based learning in an interaction design course
DEFF Research Database (Denmark)
Schultz, Nette; Christensen, Hans Peter
2004-01-01
The objective in this paper is the implementation of the highly structured seven-step PBL procedure as part of the learning process in a human-computer interaction design course at the Technical University of Denmark, taking into account the common learning processes in PBL and the interaction de...... others in a single course. The evaluation results showed that the students definitely took a deep approach to learning, and indicated clearly that the students had obtained competences not only within the traditional HCI curriculum but also in terms of team-work skills.......The objective in this paper is the implementation of the highly structured seven-step PBL procedure as part of the learning process in a human-computer interaction design course at the Technical University of Denmark, taking into account the common learning processes in PBL and the interaction...... individual reports after each case in the PBL-process in order to explore the students’ inter- and intra-personal team skills development in the learning process. Different qualitative and quantitative evaluation methods have been used to obtain a thorough evaluation of PBL used as a learning method among...
Matzat, U.
2010-01-01
Social network researchers have claimed that relations offline affect relations online; however, it is unclear which characteristics of online interaction are affected by the existence of offline relations. This article examines whether a mixture of virtual and real-life interaction—in contrast to
Lie symmetries for the electric charge-magnetic monopole interaction problem
International Nuclear Information System (INIS)
Moreira, I.C.; Ritter, O.M.; Santos, F.C.
1985-01-01
The symmetries of the equation of motion for an electric charge interacting with a magnetic monopole are analyzed. Two methods, starting from the knowledge of the Lie symmetries, are discussed and employed in this case. This procedure is also compared with the hamiltonians methods. (ltonians methods. (Author) [pt
Endendijk, Joyce; De Bruijn, Anouk T.c.e.; van Bakel, Hedwig J.A.; Wijnen, Hennie A.a.; Pop, Victor J.m.; van Baar, Anneloes
2017-01-01
The role of mother–infant interaction quality is studied in the relation between prenatal maternal emotional symptoms and child behavioralproblems. Healthy pregnant, Dutch women (N = 96, M = 31.6, SD = 3.3) were allocated to the “exposed group” (n = 46), consisting of mothers withhigh levels of
Solvability of an unsaturated porous media flow problem with thermomechanical interaction
Czech Academy of Sciences Publication Activity Database
Detmann, B.; Krejčí, Pavel; Rocca, E.
2016-01-01
Roč. 48, č. 6 (2016), s. 4175-4201 ISSN 0036-1410 R&D Projects: GA ČR(CZ) GA15-12227S Institutional support: RVO:67985840 Keywords : porous media * hysteresis * thermomechanical interactions Subject RIV: BA - General Mathematics Impact factor: 1.648, year: 2016 http://epubs.siam.org/doi/abs/10.1137/16M1056365
Przyrembel, Marisa; Smallwood, Jonathan; Pauen, Michael; Singer, Tania
2012-01-01
Successful human social interaction depends on our capacity to understand other people's mental states and to anticipate how they will react to our actions. Despite its importance to the human condition, the exact mechanisms underlying our ability to understand another's actions, feelings, and thoughts are still a matter of conjecture. Here, we consider this problem from philosophical, psychological, and neuroscientific perspectives. In a critical review, we demonstrate that attempts to draw parallels across these complementary disciplines is premature: The second-person perspective does not map directly to Interaction or Simulation theories, online social cognition, or shared neural network accounts underlying action observation or empathy. Nor does the third-person perspective map onto Theory-Theory (TT), offline social cognition, or the neural networks that support Theory of Mind (ToM). Moreover, we argue that important qualities of social interaction emerge through the reciprocal interplay of two independent agents whose unpredictable behavior requires that models of their partner's internal state be continually updated. This analysis draws attention to the need for paradigms in social neuroscience that allow two individuals to interact in a spontaneous and natural manner and to adapt their behavior and cognitions in a response contingent fashion due to the inherent unpredictability in another person's behavior. Even if such paradigms were implemented, it is possible that the specific neural correlates supporting such reciprocal interaction would not reflect computation unique to social interaction but rather the use of basic cognitive and emotional processes combined in a unique manner. Finally, we argue that given the crucial role of social interaction in human evolution, ontogeny, and every-day social life, a more theoretically and methodologically nuanced approach to the study of real social interaction will nevertheless help the field of social cognition
Przyrembel, Marisa; Smallwood, Jonathan; Pauen, Michael; Singer, Tania
2012-01-01
Successful human social interaction depends on our capacity to understand other people's mental states and to anticipate how they will react to our actions. Despite its importance to the human condition, the exact mechanisms underlying our ability to understand another's actions, feelings, and thoughts are still a matter of conjecture. Here, we consider this problem from philosophical, psychological, and neuroscientific perspectives. In a critical review, we demonstrate that attempts to draw parallels across these complementary disciplines is premature: The second-person perspective does not map directly to Interaction or Simulation theories, online social cognition, or shared neural network accounts underlying action observation or empathy. Nor does the third-person perspective map onto Theory-Theory (TT), offline social cognition, or the neural networks that support Theory of Mind (ToM). Moreover, we argue that important qualities of social interaction emerge through the reciprocal interplay of two independent agents whose unpredictable behavior requires that models of their partner's internal state be continually updated. This analysis draws attention to the need for paradigms in social neuroscience that allow two individuals to interact in a spontaneous and natural manner and to adapt their behavior and cognitions in a response contingent fashion due to the inherent unpredictability in another person's behavior. Even if such paradigms were implemented, it is possible that the specific neural correlates supporting such reciprocal interaction would not reflect computation unique to social interaction but rather the use of basic cognitive and emotional processes combined in a unique manner. Finally, we argue that given the crucial role of social interaction in human evolution, ontogeny, and every-day social life, a more theoretically and methodologically nuanced approach to the study of real social interaction will nevertheless help the field of social cognition
International Nuclear Information System (INIS)
Conn, R.W.; Gauster, W.B.; Heifetz, D.; Marmar, E.; Wilson, K.L.
1984-01-01
A technical assessment of the critical issues and problem areas in the field of plasma materials interactions (PMI) in magnetic fusion devices shows these problems to be central for near-term experiments, for intermediate-range reactor devices including D-T burning physics experiments, and for long-term reactor machines. Critical technical issues are ones central to understanding and successful operation of existing and near-term experiments/reactors or devices of great importance for the long run, i.e., ones which will require an extensive, long-term development effort and thus should receive attention now. Four subgroups were formed to assess the critical PMI issues along four major lines: (1) PMI and plasma confinement physics experiments; (2) plasma-edge modelling and theory; (3) surface physics; and (4) materials technology for in-vessel components and the first wall. The report which follows is divided into four major sections, one for each of these topics
Morgan, Judith K; Shaw, Daniel S; Olino, Thomas M
2012-08-01
Whereas socialization influences in early childhood have been linked to children's emerging internalizing problems and prosocial behavior, relatively few studies have examined how NE might moderate such associations in both advantageous and maladaptive ways. Furthermore, more research is needed to evaluate the impact of sibling relationships as an influential socialization influence on these child outcomes. In the current study we examined how NE might differentially moderate the associations between quality of relationships with siblings and both internalizing problems and social skills at school entry. NE moderated the effects of positive and destructive sibling relationship quality on child internalizing problems. Specifically, for boys high on NE, more positive sibling relationship quality predicted fewer internalizing problems, but more destructive sibling conflict predicted more internalizing problems. NE also moderated the effects of destructive sibling conflict on child social skills. For boys high on NE, destructive sibling conflict predicted fewer social skills. Boys high on NE appear to show greater susceptibility to the effects of sibling socialization on child outcomes, relative to boys low on NE. The implications of these interactions are discussed with respect to differential susceptibility theory.
Directory of Open Access Journals (Sweden)
Richard L. Einsporn
2014-01-01
Full Text Available A randomized clinical experiment to compare two types of endotracheal tubes utilized a block design where each of the six participating anesthesiologists performed tube insertions for an equal number of patients for each type of tube. Five anesthesiologists intubated at least three patients with each tube type, but one anesthesiologist intubated only one patient per tube type. Overall, one type of tube outperformed the other on all three effectiveness measures. However, analysis of the data using an interaction model gave conflicting and misleading results, making the tube with the better performance appear to perform worse. This surprising result was caused by the undue influence of the data for the anesthesiologist who intubated only two patients. We therefore urge caution in interpreting results from interaction models with designs containing small blocks.
Site response - a critical problem in soil-structure interaction analyses for embedded structures
International Nuclear Information System (INIS)
Seed, H.B.; Lysmer, J.
1986-01-01
Soil-structure interaction analyses for embedded structures must necessarily be based on a knowledge of the manner in which the soil would behave in the absence of any structure - that is on a knowledge and understanding of the spatial distribution of motions in the ground within the depth of embedment of the structure. The nature of these spatial variations is discussed and illustrated by examples of recorded motions. It is shown that both the amplitude of peak acceleration and the form of the acceleration response spectrum for earthquake motions will necessarily vary with depth and failure to take these variations into account may introduce an unwarranted degree of conservatism into the soil-structure interaction analysis procedure
Interacting with Users in Social Networks: The Follow-back Problem
2016-05-02
These functions are known as network centrali- ties. They quantify how central a vertex is to the problem at hand, with the definition of centrality ...56 4.2.2 Twitter networks . . . . . . . . . . . . . . . . . . . . . . . . . 57 4.2.3 Network centrality policies...tool can hinder the free movement of alternative ideas and information and thus can be analyzed through the A2/AD paradigm. Non-state adversaries have
Cognition-emotion interactions: patterns of change and implications for math problem solving
Trezise, Kelly; Reeve, Robert A.
2014-01-01
Surprisingly little is known about whether relationships between cognitive and emotional states remain stable or change over time, or how different patterns of stability and/or change in the relationships affect problem solving abilities. Nevertheless, cross-sectional studies show that anxiety/worry may reduce working memory (WM) resources, and the ability to minimize the effects anxiety/worry is higher in individuals with greater WM capacity. To investigate the patterns of stability and/or change in cognition-emotion relations over time and their implications for problem solving, 126 14-year-olds’ algebraic WM and worry levels were assessed twice in a single day before completing an algebraic math problem solving test. We used latent transition analysis to identify stability/change in cognition-emotion relations, which yielded a six subgroup solution. Subgroups varied in WM capacity, worry, and stability/change relationships. Among the subgroups, we identified a high WM/low worry subgroup that remained stable over time and a high WM/high worry, and a moderate WM/low worry subgroup that changed to low WM subgroups over time. Patterns of stability/change in subgroup membership predicted algebraic test results. The stable high WM/low worry subgroup performed best and the low WM capacity-high worry “unstable across time” subgroup performed worst. The findings highlight the importance of assessing variations in cognition-emotion relationships over time (rather than assessing cognition or emotion states alone) to account for differences in problem solving abilities. PMID:25132830
Problem solving - an interactive active method for teaching the thermokinetic concept
Directory of Open Access Journals (Sweden)
Odochian Lucia
2014-07-01
Full Text Available The paper describes a strategy that uses problem solving to teach the thermokinetic concept, based on student’s previously established proficiency in thermochemistry and kinetics. Chemistry teachers often use this method because it ensures easy achievement of both formative and informative science skills. This teaching strategy is tailored for students that prove special intellectual resources, Olympiad participants and to those who find chemistry a potential professional route
Cognition-emotion interactions: Patterns of change and implications for math problem solving
Directory of Open Access Journals (Sweden)
Kelly eTrezise
2014-07-01
Full Text Available Surprisingly little is known about whether relationships between cognitive and emotional states remain stable or change over time, or how different patterns of stability and/or change in the relationships affect problem solving abilities. Nevertheless, cross-sectional studies show that anxiety/worry may reduce working memory resources, and the ability to minimize the effects anxiety/worry is higher in individuals with greater WM capacity. To investigate the patterns of stability and/or change in cognition-emotion relations over time and their implications for problem solving, 126 14-year-olds’ algebraic WM and worry levels were assessed twice in a single day before completing an algebraic math problem solving test. We used latent transition analysis to identify stability/change in cognition-emotion relations, which yielded a six subgroup solution. Subgroups varied in WM capacity, worry, and stability/change relationships. Among the subgroups, we identified a high WM/low worry subgroup that remained stable over time and a high WM/high worry, and a moderate WM/low worry subgroup that changed to low WM subgroups over time. Patterns of stability/change in subgroup membership predicted algebraic test results. The stable high WM/low worry subgroup performed best and the low WM capacity-high worry unstable across time subgroup performed worst. The findings highlight the importance of assessing variations in cognition-emotion relationships over time (rather than assessing cognition or emotion states alone to account for differences in problem solving abilities.
Energy Technology Data Exchange (ETDEWEB)
Korneev, Boris [Moscow Institute of Physics and Technology, 9 Institutsky lane, Dolgoprudny 141700 (Russian Federation); Levchenko, Vadim, E-mail: boris.korneev@phystech.edu [Keldysh Institute of Applied Mathematics, 4 Miusskaya square, Moscow 125047 (Russian Federation)
2016-12-15
A set of numerical experiments on the interaction between a planar shock wave and a spherical bubble with a slightly perturbed surface is considered. Spectral analysis of the instability growth is carried out and three-dimensional Euler equations of fluid dynamics are chosen as the mathematical model for the process. The equations are solved via the Runge–Kutta discontinuous Galerkin method and the special DiamondTorre algorithm for multi-GPU implementation is used. (paper)
Mpofu, D J; Lanphear, J; Stewart, T; Das, M; Ridding, P; Dunn, E
1998-09-01
The Faculty of Medicine and Health Sciences (FMHS), United Arab Emirates (UAE) University is in a unique position to explore issues related to English language proficiency and medical student performance. All students entering the FMHS have English as a second language. This study focused on the issues of students' proficiency in English as measured by the TOEFL test, student background factors and interaction in problem-based learning (PBL) groups. Using a modification of Bales Interaction Process Analysis, four problem-based learning groups were observed over four thematic units, to measure the degree of student interaction within PBL groups and to compare this to individual TOEFL scores and key background variables. The students' contributions correlated highly with TOEFL test results in the giving of information (range r = 0.67-0.74). The female students adhered to interacting in English during group sessions, whereas the male students were more likely to revert to using Arabic in elaborating unclear phenomena (p TOEFL scores for the male students, but not for female students. Multivariate analysis was undertaken to analyse the relative contribution of the TOEFL, parental education and years of studying in English. The best predictor of students' contributions in PBL groups was identified as TOEFL scores. The study demonstrates the importance of facilitating a locally acceptable level of English proficiency prior to admission to the FMHS. However, it also highlights the importance of not focusing only on English proficiency but paying attention to additional factors in facilitating medical students in maximizing benefits from interactions in PBL settings.
Manurung, Sondang; Demonta Pangabean, Deo
2017-05-01
The main purpose of this study is to produce needs analysis, literature review, and learning tools in the study of developmental of interactive multimedia based physic learning charged in problem solving to improve thinking ability of physic prospective student. The first-year result of the study is: result of the draft based on a needs analysis of the facts on the ground, the conditions of existing learning and literature studies. Following the design of devices and instruments performed as well the development of media. Result of the second study is physics learning device -based interactive multimedia charged problem solving in the form of textbooks and scientific publications. Previous learning models tested in a limited sample, then in the evaluation and repair. Besides, the product of research has an economic value on the grounds: (1) a virtual laboratory to offer this research provides a solution purchases physics laboratory equipment is expensive; (2) address the shortage of teachers of physics in remote areas as a learning tool can be accessed offline and online; (3). reducing material or consumables as tutorials can be done online; Targeted research is the first year: i.e story board learning physics that have been scanned in a web form CD (compact disk) and the interactive multimedia of gas Kinetic Theory concept. This draft is based on a needs analysis of the facts on the ground, the existing learning conditions, and literature studies. Previous learning models tested in a limited sample, then in the evaluation and repair.
Zhu, Zheng; Andresen, Juan Carlos; Janzen, Katharina; Katzgraber, Helmut G.
2013-03-01
We study the equilibrium and nonequilibrium properties of Boolean decision problems with competing interactions on scale-free graphs in a magnetic field. Previous studies at zero field have shown a remarkable equilibrium stability of Boolean variables (Ising spins) with competing interactions (spin glasses) on scale-free networks. When the exponent that describes the power-law decay of the connectivity of the network is strictly larger than 3, the system undergoes a spin-glass transition. However, when the exponent is equal to or less than 3, the glass phase is stable for all temperatures. First we perform finite-temperature Monte Carlo simulations in a field to test the robustness of the spin-glass phase and show, in agreement with analytical calculations, that the system exhibits a de Almeida-Thouless line. Furthermore, we study avalanches in the system at zero temperature to see if the system displays self-organized criticality. This would suggest that damage (avalanches) can spread across the whole system with nonzero probability, i.e., that Boolean decision problems on scale-free networks with competing interactions are fragile when not in thermal equilibrium.
Inverse problem for the mean-field monomer-dimer model with attractive interaction
International Nuclear Information System (INIS)
Contucci, Pierluigi; Luzi, Rachele; Vernia, Cecilia
2017-01-01
The inverse problem method is tested for a class of monomer-dimer statistical mechanics models that contain also an attractive potential and display a mean-field critical point at a boundary of a coexistence line. The inversion is obtained by analytically identifying the parameters in terms of the correlation functions and via the maximum-likelihood method. The precision is tested in the whole phase space and, when close to the coexistence line, the algorithm is used together with a clustering method to take care of the underlying possible ambiguity of the inversion. (paper)
Bogatskaya, A. V.; Klenov, N. V.; Tereshonok, M. V.; Adjemov, S. S.; Popov, A. M.
2018-05-01
We present an analysis of the possibility of penetrating electromagnetic waves through opaque media using an optical-mechanical analogy. As an example, we consider the plasma sheath surrounding the vehicle as a potential barrier and analyze the overcoming of radiocommunication blackout problem. The idea is to embed a «resonator» between the surface on the vehicle and plasma sheath which is supposed to provide an effective tunneling of the signal to the receiving antenna. We discuss the peculiarities of optical mechanical analogy applicability and analyze the radio frequency wave tunneling regime in detail. The cases of normal and oblique incidence of radiofrequency waves on the vehicle surface are studied.
Computational issues and algorithm assessment for shock/turbulence interaction problems
International Nuclear Information System (INIS)
Larsson, J; Cook, A; Lele, S K; Moin, P; Cabot, B; Sjoegreen, B; Yee, H; Zhong, X
2007-01-01
The paper provides an overview of the challenges involved in the computation of flows with interactions between turbulence, strong shockwaves, and sharp density interfaces. The prediction and physics of such flows is the focus of an ongoing project in the Scientific Discovery through Advanced Computing (SciDAC) program. While the project is fundamental in nature, there are many important potential applications of scientific and engineering interest ranging from inertial confinement fusion to exploding supernovae. The essential challenges will be discussed, and some representative numerical results that highlight these challenges will be shown. In addition, the overall approach taken in this project will be outlined
Liu, Shuai; Chen, Ge; Yao, Shifeng; Tian, Fenglin; Liu, Wei
2017-07-01
This paper presents a novel integrated marine visualization framework which focuses on processing, analyzing the multi-dimension spatiotemporal marine data in one workflow. Effective marine data visualization is needed in terms of extracting useful patterns, recognizing changes, and understanding physical processes in oceanography researches. However, the multi-source, multi-format, multi-dimension characteristics of marine data pose a challenge for interactive and feasible (timely) marine data analysis and visualization in one workflow. And, global multi-resolution virtual terrain environment is also needed to give oceanographers and the public a real geographic background reference and to help them to identify the geographical variation of ocean phenomena. This paper introduces a data integration and processing method to efficiently visualize and analyze the heterogeneous marine data. Based on the data we processed, several GPU-based visualization methods are explored to interactively demonstrate marine data. GPU-tessellated global terrain rendering using ETOPO1 data is realized and the video memory usage is controlled to ensure high efficiency. A modified ray-casting algorithm for the uneven multi-section Argo volume data is also presented and the transfer function is designed to analyze the 3D structure of ocean phenomena. Based on the framework we designed, an integrated visualization system is realized. The effectiveness and efficiency of the framework is demonstrated. This system is expected to make a significant contribution to the demonstration and understanding of marine physical process in a virtual global environment.
Schlagheck, R. A.
1977-01-01
New planning techniques and supporting computer tools are needed for the optimization of resources and costs for space transportation and payload systems. Heavy emphasis on cost effective utilization of resources has caused NASA program planners to look at the impact of various independent variables that affect procurement buying. A description is presented of a category of resource planning which deals with Spacelab inventory procurement analysis. Spacelab is a joint payload project between NASA and the European Space Agency and will be flown aboard the Space Shuttle starting in 1980. In order to respond rapidly to the various procurement planning exercises, a system was built that could perform resource analysis in a quick and efficient manner. This system is known as the Interactive Resource Utilization Program (IRUP). Attention is given to aspects of problem definition, an IRUP system description, questions of data base entry, the approach used for project scheduling, and problems of resource allocation.
International Nuclear Information System (INIS)
Gonis, Antonios; Daene, Markus W.; Nicholson, Don M.; Stocks, George Malcolm
2012-01-01
We have developed and tested in terms of atomic calculations an exact, analytic and computationally simple procedure for determining the functional derivative of the exchange energy with respect to the density in the implementation of the Kohn Sham formulation of density functional theory (KS-DFT), providing an analytic, closed-form solution of the self-interaction problem in KS-DFT. We demonstrate the efficacy of our method through ground-state calculations of the exchange potential and energy for atomic He and Be atoms, and comparisons with experiment and the results obtained within the optimized effective potential (OEP) method.
International Nuclear Information System (INIS)
Bakalov, D.D.; Melezhik, V.S.
1987-01-01
The relativistic Hamiltonian for 3-spin particles with electromagnetic interaction has been represented in the form of a sum of terms with factorized dependence on spin, angular and spheroidal variable, and its matrix elements have been expressed in terms of the matrix elements of a small number of ''basic'' operators. The numerical values of the latter have been tabulated, thus allowing for the evaluation of the leading relativistic effects in any 3-body system (with unit particle charge) with and accuracy of ∼ 0(1/2M), where 1/2M=(M 1 -1 +M 2 -1 )/2(M 1 -1 +M 3 -1 ) is the small parameter of the adiabatic expansion (M i , i=1,2,3 being particle masses)
Energy Technology Data Exchange (ETDEWEB)
Brown, P J [Institut Max von Laue - Paul Langevin (ILL), 38 - Grenoble (France)
1996-11-01
A semi-quantitative analysis is given of some of the ways in which spin-lattice interactions can modify the cross-sections observable in neutron scattering experiments. This analysis is applied to the scattering from the invar alloy Fe{sub 65}Ni{sub 35} using a model in which the magnetic moment is a function of the near neighbour separation. This model has been applied to clarify the results of inelastic scattering experiments carried out on Fe{sub 65}Ni{sub 35} using both polarised and unpolarised neutrons. The extra information obtainable using polarised neutrons as well as the difficulties and limitations of the technique for inelastic scattering are discussed. (author) 8 figs., 14 refs.
International Nuclear Information System (INIS)
Caniparoli, Jean-Philippe
1988-01-01
After having determined the structural properties of smectic liquid crystals made from double chain surfactants/water binary systems, residual anisotropic interactions and relaxation times measurements were used to investigate the molecular ordering. Phosphorus, deuterium and nitrogen NMR of the surfactant molecules evidenced their high degree of order and the strong anisotropy of their motions. Quantitative results depended on the surfactant polar head -phosphate or ammonium-, while they displayed little variations with the hydrocarbon tail size. The marked dependence of the order and dynamics of small solutes in a lamellar phase on their hydrophilic or hydrophobic behaviour was shown using the same methods. By means of para-magnetically induced relaxation, it was proved that the non-polar solute benzene is located in the organic domain of the liquid crystalline matrix. (author) [fr
International Nuclear Information System (INIS)
Jo, Jong Chull; Roh, Kyung Wan; Jhung, Myung Jo
2006-12-01
During this work period, a preliminary research has been conducted in the three different and related areas as stated in the proposal: literature survey, preliminary feasibility study of LBM and FEM coupling for FSI problems, and benchmark problems. As far as the literature review was concerned, approximately one hundred articles were found for the LBM techniques and critical review has been performed. The reviewed articles were classified into several topics that are useful for a subsequent development of the proposed computer program. Those topics included immiscible multicomponent flows, flow with energy transport, coupled multi-physics applications, application of the boundary conditions, irregular lattices, and turbulence. Furthermore, some fundamental review of the LBM was also included in this report. Secondly, a description of the LBM and FEM coupling program, which has been developed so far, was described here along with some demonstration examples. The preliminary study showed a great potential of the proposed technique for FSI application. A sample computer program list is also attached as Appendix A. As a future benchmark study, a set of test cases were proposed so that experimental data would be obtained in the next phase of the study. These data would be beneficial to understand the fundamental physics of the FSI nature under different basic conditions, and also provide benchmark results against which the developed program at a later stage could be validated. Finally, the future research direction as the extension of the present work is provided with emphasis on its goal, as well as merits and benefits resulting from the proposed research for the regulatory evaluation activities of KINS and the associated technical activities of industries such as design, manufacturing, fabrication, operation and maintenance
Lagrangian and Eulerian finite element techniques for transient fluid-structure interaction problems
International Nuclear Information System (INIS)
Donea, J.; Fasoli-Stella, P.; Giuliani, S.
1977-01-01
The basic finite element equations for transient compressible fluid flow are presented in a form that allows the elements to be moved with the fluid in normal Lagrangian fashion, to be held fixed in a Eulerian manner, or to be moved in some arbitrarily specified way. The co-existence of Lagrangian and Eulerian regions within the finite element mesh will permit to handle greater distortions in the fluid motion than would be allowed by a purely Lagrangian method, with more resolution than is afforded by a purely Eulerian method. To achieve a mixed formulation, the conservation statements of mass, momentum and energy are expressed in integral form over a reference volume whose surface may be moving with an arbitrarily prescribed velocity. Direct use can be made of the integral forms of the mass and energy equations to adjust the element density and specific internal energy. The Galerkin process is employed to formulate a variational statement associated with the momentum equation. The difficulties associated with the presence of convective terms in the conservation equations are handled by expressing transports of mass, momentum and energy terms of intermediate velocities derived at each cycle from the previous cycle velocities and accelerations. The hydrodynamic elements presented are triangles, quadrilaterals with constant pressure and density. The finite element equations associated with these elements are described in the necessary detail. Numerical results are presented based on purely Lagrangian, purely Eulerian and mixed formulations. Simple problems with analytic solution are solved first to show the validity and accuracy of the proposed mixed finite element formulation. Then, practical problems are illustrated in the field of fast reactor safety analysis
Directory of Open Access Journals (Sweden)
Åse Bjørseth
Full Text Available The aim of the present investigation was to compare the effectiveness of Parent-Child Interaction Therapy (PCIT with treatment as usual (TAU in young children who were referred to regular child and adolescent mental health clinics for behavior problems.Eighty-one Norwegian families with two- to seven-year-old children (52 boys who had scored ≥ 120 on the Eyberg Child Behavior Inventory (ECBI were randomly assigned to receive either PCIT or TAU. The families were assessed 6 and 18 months after beginning treatment. Parenting skills were measured using the Dyadic Parent-Child Interaction Coding System (DPICS, and child behavior problems were measured using the ECBI and the Child Behavior Checklist (CBCL.Linear growth curve analyses revealed that the behavior problems of children receiving PCIT improved more compared with children receiving TAU according to mother reports (ECBI d = .64, CBCL d = .61, both p < .05 but not according to father report. Parents also improved with regard to Do and Don't skills (d = 2.58, d = 1.46, respectively, both p ≤ .001. At the 6-month assessment, which often occurred before treatment was finished, children who had received PCIT had lower father-rated ECBI and mother-rated CBCL-scores (p = .06 compared with those who had received TAU. At the 18-month follow-up, the children who had received PCIT showed fewer behavior problems compared with TAU according to mother (d = .37 and father (d = .56 reports on the ECBI and mother reports on the CBCL regarding externalizing problems (d = .39. Parents receiving PCIT developed more favorable Do Skills (6-month d = 1.81; 18-month d = 1.91 and Don't Skills (6-month d = 1.46; 18-month d = 1.42 according to observer ratings on the DPICS compared with those receiving TAU.Children receiving PCIT in regular clinical practice exhibited a greater reduction in behavior problems compared with children receiving TAU, and their parents' parenting skills improved to a greater degree
Leon, Stéphane; Bergond, Gilles; Vallenari, Antonella
1999-04-01
We present the tidal tail distributions of a sample of candidate binary clusters located in the bar of the Large Magellanic Cloud (LMC). One isolated cluster, SL 268, is presented in order to study the effect of the LMC tidal field. All the candidate binary clusters show tidal tails, confirming that the pairs are formed by physically linked objects. The stellar mass in the tails covers a large range, from 1.8x 10(3) to 3x 10(4) \\msun. We derive a total mass estimate for SL 268 and SL 356. At large radii, the projected density profiles of SL 268 and SL 356 fall off as r(-gamma ) , with gamma = 2.27 and gamma =3.44, respectively. Out of 4 pairs or multiple systems, 2 are older than the theoretical survival time of binary clusters (going from a few 10(6) years to 10(8) years). A pair shows too large age difference between the components to be consistent with classical theoretical models of binary cluster formation (Fujimoto & Kumai \\cite{fujimoto97}). We refer to this as the ``overmerging'' problem. A different scenario is proposed: the formation proceeds in large molecular complexes giving birth to groups of clusters over a few 10(7) years. In these groups the expected cluster encounter rate is larger, and tidal capture has higher probability. Cluster pairs are not born together through the splitting of the parent cloud, but formed later by tidal capture. For 3 pairs, we tentatively identify the star cluster group (SCG) memberships. The SCG formation, through the recent cluster starburst triggered by the LMC-SMC encounter, in contrast with the quiescent open cluster formation in the Milky Way can be an explanation to the paucity of binary clusters observed in our Galaxy. Based on observations collected at the European Southern Observatory, La Silla, Chile}
J Haabrekke, Kristin; Siqveland, Torill; Smith, Lars; Wentzel-Larsen, Tore; Walhovd, Kristine B; Moe, Vibeke
2015-10-01
This prospective, longitudinal study with data collected at four time points investigated how maternal psychiatric symptoms, substance abuse and maternal intrusiveness in interaction were related to early child language skills. Three groups of mothers were recruited during pregnancy: One from residential treatment institutions for substance abuse (n = 18), one from psychiatric outpatient treatment (n = 22) and one from well-baby clinics (n = 30). Maternal substance abuse and anti-social and borderline personality traits were assessed during pregnancy, postpartum depression at 3 months, maternal intrusiveness in interaction at 12 months, and child language skills at 2 years. Results showed that the mothers in the substance abuse group had the lowest level of education, they were younger and they were more likely to be single mothers than the mothers in the two other groups. There was a significant difference in expressive language between children born to mothers with substance abuse problems and those born to comparison mothers, however not when controlling for maternal age, education and single parenthood. No group differences in receptive language skills were detected. Results further showed that maternal intrusiveness observed in mother-child interaction at 12 months was significantly related to child expressive language at 2 years, also when controlling for socio-demographic risk factors. This suggests that in addition to addressing substance abuse and psychiatric problems, there is a need for applying treatment models promoting sensitive caregiving, in order to enhance child expressive language skills.
Maciej, Peter; Ndao, Ibrahima; Hammerschmidt, Kurt; Fischer, Julia
2013-09-23
To understand the evolution of acoustic communication in animals, it is important to distinguish between the structure and the usage of vocal signals, since both aspects are subject to different constraints. In terrestrial mammals, the structure of calls is largely innate, while individuals have a greater ability to actively initiate or withhold calls. In closely related taxa, one would therefore predict a higher flexibility in call usage compared to call structure. In the present study, we investigated the vocal repertoire of free living Guinea baboons (Papio papio) and examined the structure and usage of the animals' vocal signals. Guinea baboons live in a complex multi-level social organization and exhibit a largely tolerant and affiliative social style, contrary to most other baboon taxa. To classify the vocal repertoire of male and female Guinea baboons, cluster analyses were used and focal observations were conducted to assess the usage of vocal signals in the particular contexts. In general, the vocal repertoire of Guinea baboons largely corresponded to the vocal repertoire other baboon taxa. The usage of calls, however, differed considerably from other baboon taxa and corresponded with the specific characteristics of the Guinea baboons' social behaviour. While Guinea baboons showed a diminished usage of contest and display vocalizations (a common pattern observed in chacma baboons), they frequently used vocal signals during affiliative and greeting interactions. Our study shows that the call structure of primates is largely unaffected by the species' social system (including grouping patterns and social interactions), while the usage of calls can be more flexibly adjusted, reflecting the quality of social interactions of the individuals. Our results support the view that the primary function of social signals is to regulate social interactions, and therefore the degree of competition and cooperation may be more important to explain variation in call usage
Kristiansen, Jesper; Persson, Roger; Björk, Jonas; Albin, Maria; Jakobsson, Kristina; Östergren, Per-Olof; Ardö, Jonas
2011-01-01
To examine the risk of sleep problems associated with work stress (job strain, job demands, and decision authority), worries and pain and to investigate the synergistic interaction between these factors and traffic noise. Sleep problems and predictor variables were assessed in a cross-sectional public health survey with 12,093 respondents. Traffic noise levels were assessed using modelled A-weighted energy equivalent traffic sound levels at the residence. The risk of sleep problems was modell...
González Cornejo, Felipe A.; Cruchaga, Marcela A.; Celentano, Diego J.
2017-11-01
The present work reports a fluid-rigid solid interaction formulation described within the framework of a fixed-mesh technique. The numerical analysis is focussed on the study of a vortex-induced vibration (VIV) of a circular cylinder at low Reynolds number. The proposed numerical scheme encompasses the fluid dynamics computation in an Eulerian domain where the body is embedded using a collection of markers to describe its shape, and the rigid solid's motion is obtained with the well-known Newton's law. The body's velocity is imposed on the fluid domain through a penalty technique on the embedded fluid-solid interface. The fluid tractions acting on the solid are computed from the fluid dynamic solution of the flow around the body. The resulting forces are considered to solve the solid motion. The numerical code is validated by contrasting the obtained results with those reported in the literature using different approaches for simulating the flow past a fixed circular cylinder as a benchmark problem. Moreover, a mesh convergence analysis is also done providing a satisfactory response. In particular, a VIV problem is analyzed, emphasizing the description of the synchronization phenomenon.
Tucker, Jalie A.; Roth, David L.; Huang, Jin; Scott Crawford, M.; Simpson, Cathy A.
2012-01-01
Objective: Most problem drinkers do not seek help, and many recover on their own. A randomized controlled trial evaluated whether supportive interactive voice response (IVR) self-monitoring facilitated such “natural” resolutions. Based on behavioral economics, effects on drinking outcomes were hypothesized to vary with drinkers’ baseline “time horizons,” reflecting preferences among commodities of different value available over different delays and with their IVR utilization. Method: Recently resolved untreated problem drinkers were randomized to a 24-week IVR self-monitoring program (n = 87) or an assessment-only control condition (n = 98). Baseline interviews assessed outcome predictors including behavioral economic measures of reward preferences (delay discounting, pre-resolution monetary allocation to alcohol vs. savings). Six-month outcomes were categorized as resolved abstinent, resolved nonabstinent, unresolved, or missing. Complier average causal effect (CACE) models examined IVR self-monitoring effects. Results: IVR self-monitoring compliers (≥70% scheduled calls completed) were older and had greater pre-resolution drinking control and lower discounting than noncompliers (moderation than abstinent resolutions compared with predicted compliers in the control group with shorter time horizons and with all noncompliers. Intention-to-treat analytical models revealed no IVR-related effects. More balanced spending on savings versus alcohol predicted moderation in both approaches. Conclusions: IVR interventions should consider factors affecting IVR utilization and drinking outcomes, including person-specific behavioral economic variables. CACE models provide tools to evaluate interventions involving extended participation. PMID:22630807
International Nuclear Information System (INIS)
Bertagna, Luca; Veneziani, Alessandro
2014-01-01
Scientific computing has progressively become an important tool for research in cardiovascular diseases. The role of quantitative analyses based on numerical simulations has moved from ‘proofs of concept’ to patient-specific investigations, thanks to a strong integration between imaging and computational tools. However, beyond individual geometries, numerical models require the knowledge of parameters that are barely retrieved from measurements, especially in vivo. For this reason, recently cardiovascular mathematics considered data assimilation procedures for extracting the knowledge of patient-specific parameters from measures and images. In this paper, we consider specifically the quantification of vascular compliance, i.e. the parameter quantifying the tendency of arterial walls to deform under blood stress. Following up a previous paper, where a variational data assimilation procedure was proposed, based on solving an inverse fluid–structure interaction problem, here we consider model reduction techniques based on a proper orthogonal decomposition approach to accomplish the solution of the inverse problem in a computationally efficient way. (paper)
Verdonk, Petra; de Rijk, Angelique; Klinge, Ineke; de Vries, Anneke
2008-11-01
Highly educated Dutch women experience more work related mental health disability than their male counterparts, and yet little is known regarding the process. Using the theory of symbolic interactionism, we examined how women interpret their roles at work, during sick leave, and upon their return to work. Semi-structured interviews focusing on role perceptions and interactions with other actors were conducted with 13 women (aged 29-41 years) on sick leave or off work for periods ranging from half a year to 8 years. The women worked overtime because of work aholism, or to meet supervisors' expectations. This led to mental health problems and social isolation. Taking sick leave aided recovery, but further isolated the women. Insufficient support from the workplace and social insurance professionals intensified negative feelings. Psychological counselling provided alternatives whereby work and private roles could become more balanced. However, their reintegration into the workplace failed because the women could not implement these strategies when the organizational culture failed to change. A long lead-up time preceded sickness absence and sick leave allowed for recovery and value adjustment. However, a variety of interpretations reinforced the women's individualized focus, thereby hampering their successful reintegration. Given the importance of implementing effective sick leave prevention measures in the workplace, psychological treatment should focus on women's interactions with their work environment.
International Nuclear Information System (INIS)
Sigrist, Jean-Francois; Laine, Christian; Broc, Daniel
2006-01-01
. The paper has the following contents: Introduction; A homogenization method; Validation of the method; Conclusion. In conclusion, a homogenization method has been exposed in the present paper to deal with the modal analysis of a coupled fluid-structure problem that takes into account the presence of solid inner inclusions on the fluid domain. The basic theory of the developed homogenization method has been recalled. The fluid-structure interaction is described in terms of pressure-displacement with the corrective terms taking into account the confinement effect induced by the inclusion. From the theoretical point of view, the method is furthermore demonstrated to be physically consistent in terms of total mass conservation. The method is validated on a generic 2D case, by a comparison of calculation performed on the fluid-structure system with inclusions and on the fluid-structure modified problem without inclusions. The numerical results are identical both in terms of Eigen-frequencies, Eigenmodes and modal masses. The method can be applied to the modal analysis of a nuclear reactor
Kristiansen, Jesper; Persson, Roger; Björk, Jonas; Albin, Maria; Jakobsson, Kristina; Ostergren, Per-Olof; Ardö, Jonas
2011-02-01
To examine the risk of sleep problems associated with work stress (job strain, job demands, and decision authority), worries and pain and to investigate the synergistic interaction between these factors and traffic noise. Sleep problems and predictor variables were assessed in a cross-sectional public health survey with 12,093 respondents. Traffic noise levels were assessed using modelled A-weighted energy equivalent traffic sound levels at the residence. The risk of sleep problems was modelled using multiple logistic regression analysis. With regard to sleep problems not attributed to any external source (general sleep problems), independent main effects were found for traffic noise (women), decision authority (women), job strain, job demands, suffering from pain or other afflictions, worries about losing the job, experiencing bullying at work, having troubles paying the bills, and having a sick, disabled, or old relative to take care of (women). Significant synergistic effects were found for traffic noise and experiencing bullying at work in women. With regard to sleep problems attributed to traffic noise, strong synergistic interactions were found between traffic noise and, respectively, job demands (men), having pain or other afflictions, taking care of a sick, old, or disabled relative, and having troubles paying the bills. Main effects were found for worries about losing the job, experiencing bullying at work, job strain (men), and decision authority (men). Synergistic interactions could potentially contribute with 10-20% of the sleep problems attributed to traffic noise in the population. Work stress, pain, and different worries were independently associated with general sleep problems and showed in general no synergistic interaction with traffic noise. In contrast, synergistic effects between traffic noise and psychological factors were found with regard to sleep problems attributed to traffic noise. The synergy may contribute significantly to sleep
Halim, Dunant; Cheng, Li; Su, Zhongqing
2011-04-01
The work proposed an optimization approach for structural sensor placement to improve the performance of vibro-acoustic virtual sensor for active noise control applications. The vibro-acoustic virtual sensor was designed to estimate the interior sound pressure of an acoustic-structural coupled enclosure using structural sensors. A spectral-spatial performance metric was proposed, which was used to quantify the averaged structural sensor output energy of a vibro-acoustic system excited by a spatially varying point source. It was shown that (i) the overall virtual sensing error energy was contributed additively by the modal virtual sensing error and the measurement noise energy; (ii) each of the modal virtual sensing error system was contributed by both the modal observability levels for the structural sensing and the target acoustic virtual sensing; and further (iii) the strength of each modal observability level was influenced by the modal coupling and resonance frequencies of the associated uncoupled structural/cavity modes. An optimal design of structural sensor placement was proposed to achieve sufficiently high modal observability levels for certain important panel- and cavity-controlled modes. Numerical analysis on a panel-cavity system demonstrated the importance of structural sensor placement on virtual sensing and active noise control performance, particularly for cavity-controlled modes.
Rendall, Drew; Owren, Michael J.; Weerts, Elise; Hienz, Robert D.
2004-01-01
This study quantifies sex differences in the acoustic structure of vowel-like grunt vocalizations in baboons (Papio spp.) and tests the basic perceptual discriminability of these differences to baboon listeners. Acoustic analyses were performed on 1028 grunts recorded from 27 adult baboons (11 males and 16 females) in southern Africa, focusing specifically on the fundamental frequency (F0) and formant frequencies. The mean F0 and the mean frequencies of the first three formants were all significantly lower in males than they were in females, more dramatically so for F0. Experiments using standard psychophysical procedures subsequently tested the discriminability of adult male and adult female grunts. After learning to discriminate the grunt of one male from that of one female, five baboon subjects subsequently generalized this discrimination both to new call tokens from the same individuals and to grunts from novel males and females. These results are discussed in the context of both the possible vocal anatomical basis for sex differences in call structure and the potential perceptual mechanisms involved in their processing by listeners, particularly as these relate to analogous issues in human speech production and perception.
The nuclear N-body problem and the effective interaction in self-consistent mean-field methods
International Nuclear Information System (INIS)
Duguet, Thomas
2002-01-01
This work deals with two aspects of mean-field type methods extensively used in low-energy nuclear structure. The first study is at the mean-field level. The link between the wave-function describing an even-even nucleus and the odd-even neighbor is revisited. To get a coherent description as a function of the pairing intensity in the system, the utility of the formalization of this link through a two steps process is demonstrated. This two-steps process allows to identify the role played by different channels of the force when a nucleon is added in the system. In particular, perturbative formula evaluating the contribution of time-odd components of the functional to the nucleon separation energy are derived for zero and realistic pairing intensities. Self-consistent calculations validate the developed scheme as well as the derived perturbative formula. This first study ends up with an extended analysis of the odd-even mass staggering in nuclei. The new scheme allows to identify the contribution to this observable coming from different channels of the force. The necessity of a better understanding of time-odd terms in order to decide which odd-even mass formulae extracts the pairing gap the most properly is identified. These terms being nowadays more or less out of control, extended studies are needed to make precise the fit of a pairing force through the comparison of theoretical and experimental odd-even mass differences. The second study deals with beyond mean-field methods taking care of the correlations associated with large amplitude oscillations in nuclei. Their effects are usually incorporated through the GCM or the projected mean-field method. We derive a perturbation theory motivating such variational calculations from a diagrammatic point of view for the first time. Resuming two-body correlations in the energy expansion, we obtain an effective interaction removing the hard-core problem in the context of configuration mixing calculations. Proceeding to a
International Nuclear Information System (INIS)
Liu, Hao
2016-01-01
This Ph.D. work takes place within the framework of studies on Pellet-Cladding mechanical Interaction (PCI) which occurs in the fuel rods of pressurized water reactor. This manuscript focuses on automatic mesh refinement to simulate more accurately this phenomena while maintaining acceptable computational time and memory space for industrial calculations. An automatic mesh refinement strategy based on the combination of the Local Defect Correction multigrid method (LDC) with the Zienkiewicz and Zhu a posteriori error estimator is proposed. The estimated error is used to detect the zones to be refined, where the local sub-grids of the LDC method are generated. Several stopping criteria are studied to end the refinement process when the solution is accurate enough or when the refinement does not improve the global solution accuracy anymore. Numerical results for elastic 2D test cases with pressure discontinuity show the efficiency of the proposed strategy. The automatic mesh refinement in case of unilateral contact problems is then considered. The strategy previously introduced can be easily adapted to the multi-body refinement by estimating solution error on each body separately. Post-processing is often necessary to ensure the conformity of the refined areas regarding the contact boundaries. A variety of numerical experiments with elastic contact (with or without friction, with or without an initial gap) confirms the efficiency and adaptability of the proposed strategy. (author) [fr
Dubois-Comtois, Karine; Bernier, Annie; Tarabulsy, George M; Cyr, Chantal; St-Laurent, Diane; Lanctôt, Anne-Sophie; St-Onge, Janie; Moss, Ellen; Béliveau, Marie-Julie
2015-10-01
This study investigated different environmental and contextual factors associated with maltreated children's adjustment in foster care. Participants included 83 children (52 boys), ages 1-7 years, and their foster caregivers. Quality of interaction with the foster caregiver was assessed from direct observation of a free-play situation; foster caregiver attachment state of mind and commitment toward the child were assessed using two interviews; disruptive behavior symptoms were reported by foster caregivers. Results showed that quality of interaction between foster caregivers and children were associated with behavior problems, such that higher-quality interactions were related to fewer externalizing and internalizing problems. Foster caregivers' state of mind and commitment were interrelated but not directly associated with behavior problems of foster children. Type of placement moderated the association between foster caregiver commitment and foster child behavior problems. Whereas greater foster caregiver commitment was associated with higher levels of adjustment for children in foster families (kin and non-kin), this was not the case in foster-to-adopt families. Finally, the associations between foster child behavior problems and history of maltreatment and placement related-risk conditions fell below significance after considering child age and quality of interaction with the foster caregiver. Findings underscore the crucial contribution of the foster caregiver-child relationship to fostering child adjustment and, thereby, have important implications for clinical services offered to this population. Copyright © 2015 Elsevier Ltd. All rights reserved.
International Nuclear Information System (INIS)
Popov, A.P.; Perevezentsev, A.M.
1995-01-01
The paper defines the main problems arising in connection with organization of interaction of the administrative bodies and the forces involved in liquidation of after-effects of radiation accident. It is demonstrated that in order to increase the efficiency of interaction of the administrative bodies of various levels it is necessary to make it automatic. The paper revealed the meaning of the levels of relationship between various automatic systems. 4 refs
de Jong, Marian Elizabeth
2015-01-01
In the process of parents’ interactions with principals and teachers to resolve behaviour problems, what happens that is likely to create positive outcomes for children in school? Research literature establishes that parent interactions, whether for behaviour or academic reasons, are directed by subtly defined or invisible parameters that provide inherent institutional influence to outcomes. Bourdieu’s social reproduction theory, which relates to the influence of cultural, social, and symbo...
International Nuclear Information System (INIS)
Brooks, B.R.
1979-09-01
The Graphical Unitary Group Approach (GUGA) was cast into an extraordinarily powerful form by restructuring the Hamiltonian in terms of loop types. This restructuring allows the adoption of the loop-driven formulation which illuminates vast numbers of previously unappreciated relationships between otherwise distinct Hamiltonian matrix elements. The theoretical/methodological contributions made here include the development of the loop-driven formula generation algorithm, a solution of the upper walk problem used to develop a loop breakdown algorithm, the restriction of configuration space employed to the multireference interacting space, and the restructuring of the Hamiltonian in terms of loop types. Several other developments are presented and discussed. Among these developments are the use of new segment coefficients, improvements in the loop-driven algorithm, implicit generation of loops wholly within the external space adapted within the framework of the loop-driven methodology, and comparisons of the diagonalization tape method to the direct method. It is also shown how it is possible to implement the GUGA method without the time-consuming full (m 5 ) four-index transformation. A particularly promising new direction presented here involves the use of the GUGA methodology to obtain one-electron and two-electron density matrices. Once these are known, analytical gradients (first derivatives) of the CI potential energy are easily obtained. Several test calculations are examined in detail to illustrate the unique features of the method. Also included is a calculation on the asymmetric 2 1 A' state of SO 2 with 23,613 configurations to demonstrate methods for the diagonalization of very large matrices on a minicomputer. 6 figures, 6 tables
Sutherland, Kevin S.; Conroy, Maureen A.; Algina, James; Ladwig, Crystal; Jesse, Gabriel; Gyure, Maria
2018-01-01
Research has consistently linked early problem behavior with later adjustment problems, including antisocial behavior, learning problems and risk for the development of emotional/behavioral disorders (EBDs). Researchers have focused upon developing effective intervention programs for young children who arrive in preschool exhibiting chronic…
Rosales, Javier; Vicente, Santiago; Chamoso, Jose M.; Munez, David; Orrantia, Josetxu
2012-01-01
Word problem solving involves the construction of two different mental representations, namely, mathematical and situational. Although educational research in word problem solving has documented different kinds of instruction at these levels, less is known about how both representational levels are evoked during word problem solving in day-to-day…
DEFF Research Database (Denmark)
Jochum, Elizabeth; Borggreen, Gunhild; Murphey, TD
This paper considers the impact of visual art and performance on robotics and human-computer interaction and outlines a research project that combines puppetry and live performance with robotics. Kinesics—communication through movement—is the foundation of many theatre and performance traditions ...
Gilemkhanova, Elvira N.
2016-01-01
The changes in contemporary social and cultural environment determine the necessity to increase the efficiency of adaptive mechanisms, especially for those categories of people who are subject to social risks. One of those categories is students prone to chemical addictions. To study the relationship of forms of social interaction with problems of…
2012-01-01
Background Research into neural mechanisms of drug abuse risk has focused on the role of dysfunction in neural circuits for reward. In contrast, few studies have examined the role of dysfunction in neural circuits of threat in mediating drug abuse risk. Although typically regarded as a risk factor for mood and anxiety disorders, threat-related amygdala reactivity may serve as a protective factor against substance use disorders, particularly in individuals with exaggerated responsiveness to reward. Findings We used well-established neuroimaging paradigms to probe threat-related amygdala and reward-related ventral striatum reactivity in a sample of 200 young adult students from the ongoing Duke Neurogenetics Study. Recent life stress and problem drinking were assessed using self-report. We found a significant three-way interaction between threat-related amygdala reactivity, reward-related ventral striatum reactivity, and recent stress, wherein individuals with higher reward-related ventral striatum reactivity exhibit higher levels of problem drinking in the context of stress, but only if they also have lower threat-related amygdala reactivity. This three-way interaction predicted both contemporaneous problem drinking and problem drinking reported three-months later in a subset of participants. Conclusions These findings suggest complex interactions between stress and neural responsiveness to both threat and reward mediate problem drinking. Furthermore, they highlight a novel protective role for threat-related amygdala reactivity against drug use in individuals with high neural reactivity to reward. PMID:23151390
Marsman, Rianne; Oldehinkel, Albertine J; Ormel, Johan; Buitelaar, Jan K
2013-08-30
Although externalizing behavior problems show in general a high stability over time, the course of externalizing behavior problems may vary from individual to individual. Our main goal was to investigate the predictive role of parenting on externalizing behavior problems. In addition, we investigated the potential moderating role of gender and genetic risk (operationalized as familial loading of externalizing behavior problems (FLE), and presence or absence of the dopamine receptor D4 (DRD4) 7-repeat and 4-repeat allele, respectively). Perceived parenting (rejection, emotional warmth, and overprotection) and FLE were assessed in a population-based sample of 1768 10- to 12-year-old adolescents. Externalizing behavior problems were assessed at the same age and 212 years later by parent report (CBCL) and self-report (YSR). DNA was extracted from blood samples. Parental emotional warmth predicted lower, and parental overprotection and rejection predicted higher levels of externalizing behavior problems. Whereas none of the parenting factors interacted with gender and the DRD4 7-repeat allele, we did find interaction effects with FLE and the DRD4 4-repeat allele. That is, the predictive effect of parental rejection was only observed in adolescents from low FLE families and the predictive effect of parental overprotection was stronger in adolescents not carrying the DRD4 4-repeat allele. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.
Bourne, D.P.; Elman, H.; Osborn, J.E.
2009-01-01
This paper is the second part of a two-part paper treating a non-self-adjoint quadratic eigenvalue problem for the linear stability of solutions to the Taylor-Couette problem for flow of a viscous liquid in a deformable cylinder, with the cylinder modelled as a membrane. The first part formulated
van Dijk, Rianne; Dekovic, Maja; Bunte, Tessa L; Schoemaker, Kim; Zondervan-Zwijnenburg, Mariëlle; Espy, Kimberly A; Matthys, Walter
2017-01-01
Previous research has shown links between parenting and externalizing behavior problems in young children over time. Associations between inhibitory control, one of the executive functions, and externalizing behavior problems are widely established as well. Yet, the role of inhibitory control in the
Van Doorn, Marleen M. E. M.; Kuijpers, Rowella C. W. M.; Lichtwarck-aschoff, Anna; Bodden, Denise; Jansen, Mélou; Granic, Isabela
2016-01-01
The relation between maternal depressive symptoms and children’s mental health problems has been well established. However, prior studies have predominantly focused on maternal reports of children’s mental health problems and on parenting behavior, as a broad and unilateral concept. This
Steif, Paul S.; Fu, Luoting; Kara, Levent Burak
2016-01-01
Problems faced by engineering students involve multiple pathways to solution. Students rarely receive effective formative feedback on handwritten homework. This paper examines the potential for computer-based formative assessment of student solutions to multipath engineering problems. In particular, an intelligent tutor approach is adopted and…
Van der Giessen, D.; Hollenstein, T.; Hale, W.W.; Koot, H.M.; Meeus, W.H.J.; Branje, S.J.T.
2015-01-01
Emotional variability reflects the ability to flexibly switch among a broad range of positive and negative emotions from moment-to-moment during interactions. Emotional variability during mother-adolescent conflict interactions is considered to be important for healthy socio-emotional functioning of
Lee, Dong Ho; Lee, Jae Young; Lee, Kyung Bun; Han, Joon Koo
2017-11-01
Purpose To determine factors that significantly affect the focal disturbance (FD) ratio calculated with an acoustic structure quantification (ASQ) technique in a dietary-induced fatty liver disease rat model and to assess the diagnostic performance of the FD ratio in the assessment of hepatic steatosis by using histopathologic examination as a standard of reference. Materials and Methods Twenty-eight male F344 rats were fed a methionine-choline-deficient diet with a variable duration (3.5 days [half week] or 1, 2, 3, 4, 5, or 6 weeks; four rats in each group). A control group of four rats was maintained on a standard diet. At the end of each diet period, ASQ ultrasonography (US) and magnetic resonance (MR) spectroscopy were performed. Then, the rat was sacrificed and histopathologic examination of the liver was performed. Receiver operating characteristic curve analysis was performed to assess the diagnostic performance of the FD ratio in the evaluation of the degree of hepatic steatosis. The Spearman correlation coefficient was calculated to assess the correlation between the ordinal values, and multivariate linear regression analysis was used to identify significant determinant factors for the FD ratio. Results The diagnostic performance of the FD ratio in the assessment of the degree of hepatic steatosis (area under the receiver operating characteristic curve: 1.000 for 5%-33% steatosis, 0.981 for >33% to 66% steatosis, and 0.965 for >66% steatosis) was excellent and was comparable to that of MR spectroscopy. There was a strong negative linear correlation between the FD ratio and the estimated fat fraction at MR spectroscopy (Spearman ρ, -0.903; P analysis showed that the degree of hepatic steatosis (P ratio. Conclusion The FD ratio may potentially provide good diagnostic performance in the assessment of the degree of hepatic steatosis, with a strong negative linear correlation with the estimated fat fraction at MR spectroscopy. The degree of steatosis and
Logunova, O. S.; Sibileva, N. S.
2017-12-01
The purpose of the study is to increase the efficiency of the steelmaking process in large capacity arc furnace on the basis of implementation a new decision-making system about the composition of charge materials. The authors proposed an interactive builder for the formation of the optimization problem, taking into account the requirements of the customer, normative documents and stocks of charge materials in the warehouse. To implement the interactive builder, the sets of deterministic and stochastic model components are developed, as well as a list of preferences of criteria and constraints.
Yu, Rongqin; Branje, Susan; Keijsers, Loes; Meeus, Wim
2015-01-01
This longitudinal study examined person-environment interplay by testing interaction effects between adolescent personality type (i.e., overcontrollers, undercontrollers, and resilients) and young adult romantic relationship quality on young adult delinquency and anxiety. The study employed six
Yu, Rongqin; Branje, Susan; Keijsers, Loes; Meeus, W.H.J.
This longitudinal study examined person–environment interplay by testing interaction effects between adolescent personality type (i.e., overcontrollers, undercontrollers, and resilients) and young adult romantic relationship quality on young adult delinquency and anxiety. The study employed six
Burt, S. A.; Klump, K. L.
2018-01-01
Background Prior research has suggested that, consistent with the diathesis–stress model of gene–environment interaction (G × E), parent–child conflict activates genetic influences on antisocial/externalizing behaviors during adolescence. It remains unclear, however, whether this model is also important during childhood, or whether the moderation of child conduct problems by negative/conflictive parenting is better characterized as a bioecological interaction, in which environmental influences are enhanced in the presence of environmental risk whereas genetic influences are expressed most strongly in their absence. The current study sought to distinguish between these possibilities, evaluating how the parent–child relationship moderates the etiology of childhood-onset conduct problems. Method We conducted a series of ‘latent G by measured E’ interaction analyses, in which a measured environmental variable was allowed to moderate both genetic and environmental influences on child conduct problems. Participants included 500 child twin pairs from the Michigan State University Twin Registry (MSUTR). Results Shared environmental influences on conduct problems were found to be several-fold larger in those with high levels of parent–child conflict as compared with those with low levels. Genetic influences, by contrast, were proportionally more influential at lower levels of conflict than at higher levels. Conclusions Our findings suggest that, although the diathesis–stress form of G × E appears to underlie the relationship between parenting and conduct problems during adolescence, this pattern of moderation does not extend to childhood. Instead, results were more consistent with the bioecological form of G × E which postulates that, in some cases, genetic influences may be most fully manifested in the absence of environmental risk. PMID:23746066
CSIR Research Space (South Africa)
Haelterman, R
2016-07-01
Full Text Available be mathematically stated in the following form: F (g) = pS(p) = g, (1) where F : DF ⊂ Rm → Rn : g 7→ F (g) and S : DS ⊂ Rn → Rm : p 7→ S(p). Each equation describes (the discretized equations of) a physical problem that is spatially decomposed. In fluid... physical problem, it often represents the equations obtained after discretizing the continuous equations in time and space, and thus only represents the evolution over one time-step (see §3). This is an example of how we could be presented with a series...
Morgan, Judith K.; Shaw, Daniel S.; Olino, Thomas M.
2012-01-01
Whereas socialization influences in early childhood have been linked to children's emerging internalizing problems and prosocial behavior, relatively few studies have examined how NE might moderate such associations in both advantageous and maladaptive ways. Furthermore, more research is needed to evaluate the impact of sibling relationships as an…
Cook, David A; Thompson, Warren G; Thomas, Kris G; Thomas, Matthew R
2009-03-01
Adaptation to learning styles has been proposed to enhance learning. We hypothesized that learners with sensing learning style would perform better using a problem-first instructional method while intuitive learners would do better using an information-first method. Randomized, controlled, crossover trial. Resident ambulatory clinics. 123 internal medicine residents. Four Web-based modules in ambulatory internal medicine were developed in both "didactic" (information first, followed by patient problem and questions) and "problem" (case and questions first, followed by information) format. Knowledge posttest, format preference, learning style (Index of Learning Styles). Knowledge scores were similar between the didactic (mean +/- standard error, 83.0 +/- 0.8) and problem (82.3 +/- 0.8) formats (p = .42; 95% confidence interval [CI] for difference, -2.3 to 0.9). There was no difference between formats in regression slopes of knowledge scores on sensing-intuitive scores (p = .63) or in analysis of knowledge scores by styles classification (sensing 82.5 +/- 1.0, intermediate 83.7 +/- 1.2, intuitive 81.0 +/- 1.5; p = .37 for main effect, p = .59 for interaction with format). Format preference was neutral (3.2 +/- 0.2 [1 strongly prefers didactic, 6 strongly prefers problem], p = .12), and there was no association between learning styles and preference (p = .44). Formats were similar in time to complete modules (43.7 +/- 2.2 vs 43.2 +/- 2.2 minutes, p = .72). Starting instruction with a problem (versus employing problems later on) may not improve learning outcomes. Sensing and intuitive learners perform similarly following problem-first and didactic-first instruction. Results may apply to other instructional media.
International Nuclear Information System (INIS)
Yukhnovs'kij, Yi.R.; Kobrin, O.Je.; Tokarchuk, M.V.; Tokarevs'kij, V.V.
1997-01-01
The main forms of the existence of nuclear fuel and major concomitant factors of nuclear and ecological danger of the object 'Shelter' are presented. The processes of interaction between water and fuel containing materials have been analysed on the basis of experimental data
International Nuclear Information System (INIS)
Inoue, Tadashi; Yokoyama, Hayaichi
1982-01-01
Immiscibility and crystallization, and chemical interaction with stainless steel, SUS 304, which is designed as a canister material, were investigated on non-radioactive glasses with simulated waste of 26.4 wt%. Although glasses whose initial color was black changed to yellow or yellow-brown by heat-treatment at 600 0 C, the change of color was hardly observed by the treatment at 850 0 C. Molybdenum oxide and molybdate were detected in all heat-treated glasses. It was deduced that the compounds were existing as meta-stable particle corresponding to immiscibility particle at 600 0 C and as stable crystallized particle at 850 0 C. The chemical interaction occurred at the interface between glasses and SUS 304, whose surface was attacked by boundary corrosion proceeding to uniform corrosion with increasing temperature and time. Chromium oxide layer was mainly formed in the region suffered chemical interaction. It was deduced that the chemical interaction was moderated due to the formation of protective layer, which mainly consisted of nickel oxide, at the same time as the formation of Cr 2 O 3 layer. (author)
da Silva, André Constantino; Freire, Fernanda Maria Pereira; de Arruda, Alan Victor Pereira; da Rocha, Heloísa Vieira
2013-01-01
e-Learning environments offer content, such text, audio, video, animations, using the Web infrastructure and they are designed to users interacting with keyboard, mouse and a medium-sized screen. Mobile devices, such as smartphones and tablets, have enough computation power to render Web pages, allowing browsing the Internet and access e-Learning…
Directory of Open Access Journals (Sweden)
Susana Correnti
2016-01-01
Full Text Available The «PBL working environment» is a virtual environment developed in the framework of SCENE project (profeSsional development for an effeCtive PBL approach: a practical experiENce through ICT-enabled lEarning solution, co-funded by the European Lifelong Learning Program. The «PBL working environment» is devoted to prepare headmasters and teachers of secondary and vocational schools to use Problem-Based Learning (PBL pedagogy effectively. It is a student-centered pedagogy where learners are «actively» engaged in real world problems to solve or challenges to meet. Students develop problem-solving, self-directed learning and team skills. The «PBL working environment» is an virtual tool including three main elements: e-learning platform, virtual facilitator and PBL repository. Teachers, trainers and headmasters/school managers learn the PBL pedagogy by attending an on-line course (e-learning platform delivered through the «inductive method». It allows learners to experience PBL approach, by practicing it stage by stage, and then learn to turn practice into theory by abstracting their experience to build a theoretical understanding. Since generating the proper scenario is the most critical aspect of PBL, after benefiting from the on-line course, users can benefit from a further support: the Virtual Facilitator. It provides tips and hints on how correctly design a problem scenario and by asking questions to collect data on user's specific needs. The Virtual Facilitator is able to provide a/or more suitable example(s which match as closest as possible the teacher/trainer need. Finally, users can share problem scenarios and projects of different subjects of studies and with different characteristics uploaded and downloaded in the PBL repository.
Abouzari, Mehdi; Oberg, Scott; Gruber, Aaron; Tata, Matthew
2015-09-15
Problem gambling is thought to be highly comorbid with attention-deficit hyperactivity disorder (ADHD). We propose that the neurobiological pathologies underlying problem gambling overlap with those in ADHD. In this study, we used a simplified computerized version of the Iowa Gambling Task (IGT) to assess differences in reinforcement-driven choice adaptation among participants with pathological gambling and/or ADHD. The task contained two choice options with different net payouts over the session; a good bet that resulted in a win of +50 points on 60% of trials (and -50 points on 40%), and a bad bet that resulted in +100 points on 40% of the trials (and -100 points on 60%). We quantified participants' preference for the good bet over the session and their sensitivity to reinforcement. Both the control subjects and medicated ADHD nongamblers significantly increased the proportion of good bets over the 400-trial session. Subjects with problem gambling performed worse than controls and ADHD nongamblers, but better than our limited sample of unmedicated ADHD gamblers. Control subjects, medicated ADHD nongamblers, and unmedicated ADHD nongamblers tended to tolerate losses following good bets, whereas unmedicated ADHD gamblers tended to tolerate losses following bad bets. These data reveal that ADHD, particularly when treated with medication, is not associated with poor choices on the IGT, but may exacerbate pathological choices in problem gamblers. It seems that stabilization of dopamine signaling that occurs when ADHD is treated is itself also a treatment for certain forms of problem gambling. Crown Copyright © 2015. Published by Elsevier B.V. All rights reserved.
Li, Angel Yee-Lam; Lo, Barbara Chuen-Yee; Cheng, Cecilia
2018-06-01
Studies have shown that children frequently experiencing poor parent-child interaction are prone to video gaming-related problems, but it is unclear which specific aspects of such an interaction play a predictive role in the problems. To extend previous research that relies primarily on the self-report method to assess parent-child interaction, we conducted a longitudinal, mixed-methods study. In a laboratory setting, three major aspects of interaction (i.e., affectivity, cohesiveness, and parental behavior) were observed in 241 parent-child dyads (Children: 43 percent female, age range = 8-15, M age = 12.09, SD age = 1.41; Parents: 78 percent female, age range = 27-63, M age = 44.44, SD age = 6.09). In addition, both parent and children participants completed questionnaires that measured children's symptoms of Internet gaming disorder (IGD) and exposure to violent video games at baseline (Time 1) and 12 months later (Time 2). The results revealed that at Time 1, positive affectivity and cohesiveness were inversely associated with child-report symptoms of IGD. Also, Time 1 coerciveness (i.e., control dimension of parental behavior) was positively associated with Time 1 child-report exposure to violent video games and Time 2 child-report symptoms of IGD, respectively. Apart from main effects, the results also showed that Time 1 negative affectivity moderated the protective effects of Time 1 positive affectivity on Time 1 parent-report and Time 2 child-report exposure to violent video games, respectively. Overall, this study identifies various key aspects of parent-child interaction that may serve as concurrent or temporal predictors of video gaming-related issues.
International Nuclear Information System (INIS)
Astaf'ev, V.A.
1985-01-01
The paper reviews the mathematical methods used for analyzing the experimental data obtained in investigations of cosmic rays of superhigh energies (10 14 -10 19 eV). The analysis is carried out on the basis of the direct problem solution, i.e. calculation of the characteristics of nuclear-electromagnetic cascade showers developed in the atmosphere with regard to the specific features of experimental devices. The analytical and numerical metods for solving equations describing shower development, as well as simulation of cascade processes by the Monte Carlo method are applied herein
Czech Academy of Sciences Publication Activity Database
Petrov, A. G.; Kharlamov, Alexander A.
2013-01-01
Roč. 48, č. 5 (2013), s. 577-587 ISSN 0015-4628 R&D Projects: GA ČR(CZ) GA103/09/2066 Grant - others:Development of the Scientific Potential of the Higher Schoo(RU) 2.1.2/3604; Russian Foundation for Basic Research (RU) 11- 01-005355 Institutional support: RVO:67985874 Keywords : lubrication layer theory * viscous and inviscid fluids * thin layer * vicinity of a contact * three-dimensional problems Subject RIV: BK - Fluid Dynamics Impact factor: 0.320, year: 2013
Sievertsen, Niels; Carreira, Erick M
2018-02-01
Mobile devices such as smartphones are carried in the pockets of university students around the globe and are increasingly cheap to come by. These portable devices have evolved into powerful and interconnected handheld computers, which, among other applications, can be used as advanced learning tools and providers of targeted, curated content. Herein, we describe Apoc Social (Advanced Problems in Organic Chemistry Social), a mobile application that assists both learning and teaching college-level organic chemistry both in the classroom and on the go. With more than 750 chemistry exercises available, Apoc Social facilitates collaborative learning through discussion boards and fosters enthusiasm for complex organic chemistry.
Directory of Open Access Journals (Sweden)
Maj-Lis Follér
Full Text Available This article deals with methodological issues and how to link global processes - social and ecological - with environmental changes and human health in local communities. The discussion concerns how interdisciplinary approaches can help us find tools to develop new knowledge. Scientific knowledge and local knowledge are not seen as opposite epistemological forms, but as socially and culturally constructed. Power and social legitimacy have to be included when analyzing how to deal with the interaction between global processes and local environmental change and the health/disease interface.
Poustka, Luise; Zohsel, Katrin; Blomeyer, Dorothea; Jennen-Steinmetz, Christine; Schmid, Brigitte; Trautmann-Villalba, Patricia; Hohmann, Sarah; Becker, Katja; Esser, Günter; Schmidt, Martin H; Brandeis, Daniel; Banaschewski, Tobias; Laucht, Manfred
2015-11-01
Recent longitudinal studies have indicated that affective and behavioral dysregulation in childhood is associated with an increased risk for various negative outcomes in later life. However, few studies to date have examined early mechanisms preceding dysregulation during early childhood. Aim of this study was to elucidate early mechanisms relating to dysregulation in later life using data from an epidemiological cohort study on the long-term outcome of early risk factors from birth to adulthood. At age 3 months, mothers and infants were videotaped during a nursing and playing situation. Maternal responsiveness was evaluated by trained raters. Infant regulatory problems were assessed on the basis of a parent interview and direct observation by trained raters. At age 8 and 11 years, 290 children (139 males) were rated on the Child Behavior Checklist (CBCL). Additionally, participants were genotyped for the dopamine D4 receptor (DRD4) exon 3 VNTR polymorphism. A significant three-way interaction between maternal responsiveness, DRD4 genotype and infant regulatory problems was detected predicting the CBCL-dysregulation profile (CBCL-DP). Carriers of the DRD4 7r allele with regulatory problems at age 3 months showed significantly more behavior problems associated with the CBCL-DP during childhood when exposed to less maternal responsiveness. In contrast, no effect of maternal responsiveness was observed in DRD4 7r carriers without infant regulatory problems and in non-carriers of the DRD4 7r allele. This prospective longitudinal study extends earlier findings regarding the association of the CBCL-DP with early parenting and later psychopathology, introducing both DRD4 genotype and infant regulatory problems as important moderators. Copyright © 2015 Elsevier Ltd. All rights reserved.
Trout, Joseph; Bland, Jared
2013-03-01
In this pilot project, one hour of lecture time was replaced with one hour of in-class assignments, which groups of students collaborated on. These in-class assignments consisted of problems or projects selected for the calculus-based introductory physics students The first problem was at a level of difficulty that the majority of the students could complete with a small to moderate amount of difficulty. Each successive problem was increasingly more difficult, the last problem being having a level of difficulty that was beyond the capabilities of the majority of the students and required some instructor intervention. The students were free to choose their own groups. Students were encouraged to interact and help each other understand. The success of the in-class exercises were measured using pre-tests and post-tests. The pre-test and post-test were completed by each student independently. Statistics were also compiled on each student's attendance record and the amount of time spent reading and studying, as reported by the student. Statistics were also completed on the student responses when asked if they had sufficient time to complete the pre-test and post-test and if they would have completed the test with the correct answers if they had more time. The pre-tests and post-tests were not used in the computation of the grades of the students.
Directory of Open Access Journals (Sweden)
Hossein Ghamari-Givi
2012-10-01
Full Text Available Objective: The aim of this study was to consider the effectiveness of Applied Behavioral Analysis (ABA therapy and Treatment and Education of Autistic and related Communication handicapped children (TEACCH on stereotyped behavior, interactional and communicational problems in the autistic Children. Materials & Methods: Subjects of this experimental study were all of children in Tabriz autism school in second half of year 1388. Sample size was 29 children (21 boys and 8 girls in age range of 6-14 who were selected using random sampling method and were placed in Applied Behavioral Analysis group (8 boys and 2 girls, Treatment- Education group (9 boys and 1 girl, and control group (4 boys and 5 girls. The two scales applied for the study were Modified Checklist for Autism in Toddlers and Gilliam Autism Rating Scale. The data were analyzed using analysis of covariance. Results: The results of the research showed that the means of behavioral problem indicators in both ABA and TEACCH methods were reduced significantly in comparison with control group (P<0.01. Also in comparison of ABA therapy and TEACCH method, decline in the mean scores of communication problems was significant and in favour of ABA therapy (P<0.05. Conclusion: According to the results of study, although both ABA therapy and TEACCH method were effective in reducing symptoms of behavioral problems but because of being more effective, Applied Behavioral Analysis is suggested as a selective therapeutic approach for this research.
Pasalich, Dave S; Dadds, Mark R; Hawes, David J
2014-11-30
Callous-unemotional (CU) traits and autism spectrum disorders (ASD) symptoms are characterized by problems in empathy; however, these behavioral features are rarely examined together in children with conduct problems. This study investigated additive and interactive effects of CU traits and ASD symptoms in relation to cognitive and affective empathy in a non-ASD clinic-referred sample. Participants were 134 children aged 3 to 9 years (M=5.60; 79% boys) with oppositional defiant/conduct disorder, and their parents. Clinicians, teachers, and parents reported on dimensions of child behavior, and parental reports of family dysfunction and direct observations of parental warmth/responsiveness assessed quality of family relationships. Results from multiple regression analysis showed that, over and above the effects of child conduct problem severity and quality of family relationships, both ASD symptoms and CU traits were uniquely associated with deficits in cognitive empathy. Moreover, CU traits demonstrated an independent association with affective empathy, and this relationship was moderated by ASD symptoms. That is, there was a stronger negative association between CU traits and affective empathy at higher versus lower levels of ASD symptoms. These findings suggest including both CU traits and ASD-related social impairments in models delineating the atypical development of empathy in children with conduct problems. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.
van den Aarssen, Laura G; Bringmann, Torsten; Pfrommer, Christoph
2012-12-07
The cold dark matter paradigm describes the large-scale structure of the Universe remarkably well. However, there exists some tension with the observed abundances and internal density structures of both field dwarf galaxies and galactic satellites. Here, we demonstrate that a simple class of dark matter models may offer a viable solution to all of these problems simultaneously. Their key phenomenological properties are velocity-dependent self-interactions mediated by a light vector messenger and thermal production with much later kinetic decoupling than in the standard case.
Moore, Robert C.; Cohen, Michael H.
1993-09-01
Under this effort, SRI has developed spoken-language technology for interactive problem solving, featuring real-time performance for up to several thousand word vocabularies, high semantic accuracy, habitability within the domain, and robustness to many sources of variability. Although the technology is suitable for many applications, efforts to date have focused on developing an Air Travel Information System (ATIS) prototype application. SRI's ATIS system has been evaluated in four ARPA benchmark evaluations, and has consistently been at or near the top in performance. These achievements are the result of SRI's technical progress in speech recognition, natural-language processing, and speech and natural-language integration.
International Nuclear Information System (INIS)
Kusainov, A.M.; Neudatchin, V.G.; Obukhovsky, I.T.
1991-01-01
A modification of the resonating-group method (RGM) is proposed which includes the multiquark shell-model configurations in the nucleon overlap region. The instanton, gluon, and π,σ exchange is taken into account, the interaction constants being consistent with the baryon spectrum. This enables one to cover a wide interval of NN scattering energies up to E lab =2 GeV. The projection of the six-quark wave function onto the NN and other baryon channels is discussed in detail in our approach and in other RGM versions as well, and in this context the problem of repulsive core in the NN forces is discussed
Pierce, S. A.
2014-12-01
Geosciences are becoming increasingly data intensive, particularly in relation to sustainability problems, which are multi-dimensional, weakly structured and characterized by high levels of uncertainty. In the case of complex resource management problems, the challenge is to extract meaningful information from data and make sense of it. Simultaneously, scientific knowledge alone is insufficient to change practice. Creating tools, and group decision support processes for end users to interact with data are key challenges to transforming science-based information into actionable knowledge. The ENCOMPASS project began as a multi-year case study in the Atacama Desert of Chile to design and implement a knowledge transfer model for energy-water-mining conflicts in the region. ENCOMPASS combines the use of cyberinfrastructure (CI), automated data collection, interactive interfaces for dynamic decision support, and participatory modelling to support social learning. A pilot version of the ENCOMPASS CI uses open source systems and serves as a structure to integrate and store multiple forms of data and knowledge, such as DEM, meteorological, water quality, geomicrobiological, energy demand, and groundwater models. In the case study, informatics and data fusion needs related to scientific uncertainty around deep groundwater flowpaths and energy-water connections. Users may upload data from field sites with handheld devices or desktops. Once uploaded, data assets are accessible for a variety of uses. To address multi-attributed decision problems in the Atacama region a standalone application with touch-enabled interfaces was created to improve real-time interactions with datasets by groups. The tool was used to merge datasets from the ENCOMPASS CI to support exploration among alternatives and build shared understanding among stakeholders. To date, the project has increased technical capacity among stakeholders, resulted in the creation of both for-profit and non
Holzhausen, K. P.; Gaertner, K. P.
1985-01-01
A significant problem concerning the integration of display and switching functions is related to the fact that numerous informative data which have to be processed by man must be read from only a few display devices. A satisfactory ergonomic design of integrated display devices and keyboards is in many cases difficult, because not all functions which can be displayed and selected are simultaneously available. A technical solution which provides an integration of display and functional elements on the basis of the highest flexibility is obtained by using a cathode ray tube with a touch-sensitive screen. The employment of an integrated data input/output system is demonstrated for the cases of onboard and ground-based flight control. Ergonomic studies conducted to investigate the suitability of an employment of touch-sensitive screens are also discussed.
Ducharme, Joseph M; Folino, Anthony; Derosie, Janine
2008-01-01
Errorless acquiescence training (EAT) was developed as a graduated, success-focused, and short-term intervention for building social skills. The approach focuses on building the skill of acquiescence (i.e., teaching children to be flexible with the needs and will of peers). The authors predict that acquiescence would serve as a keystone, that is, a skill that when trained produces widespread improvements in child behavior, including reductions in antisocial behavior. The authors provide EAT to eight children referred to a clinical classroom for severe antisocial behavior. Consistent with errorless paradigms, key intervention components present at the initiation of intervention are systematically faded at a slow enough rate to ensure continued prosocial interactions throughout and following treatment. Children demonstrate substantial increases in acquiescent responding and other prosocial behavior as well as covariant reductions in antisocial behaviors. Acquiescence is discussed in terms of its potential as a keystone for prosocial responding in children with antisocial behavior.
International Nuclear Information System (INIS)
Slavin, J.A.
1982-01-01
A series of bow shock studies conducted for the purpose of investigating the interaction between the solar wind and the terrestrial planets is presented. Toward this end appropriate modeling techniques have been developed and applied to the bow wave observations at Venus, Earth, and Mars. For Mercury the measurements are so few in number that no accurate determination of shock shape was deemed possible. Flow solutions generated using the observed bow wave surface as a boundary condition in a single fluid variable obstacle shape gasdynamic model produced excellent fits to the measured width and shape of the earth's magnetosheath. This result and the observed ordering of shock shape and position by upstream sonic Mach number provide strong support for the validity of the gasdynamic approximation. At Mercury the application of earth type models to the individual Mariner 10 boundry crossings has led to the determination of an effective planetary magnetic moment of 6+-2 x 10 22 G-cm 3 . Consistent with the presence of a small terrestrial style magnetosphere, southward interplanetary magnetic fields were found to significantly reduce the solar wind stand-off distance most probably through the effects of dayside magnetic reconnection. For Venus the low altitude solar wind flow field derived from gasdynamic modeling of bow shock location and shape indicates that a fraction of the incident streamlines are absorbed by the neutral atmosphere near the ionopause; approximately 1% and 8%, respectively, in the solar maximum Pioneer Venus and solar minimum Venera measurements. Accordingly, it appears that cometary processes must be included in model calculations of the solar wind flow about Venus. At Mars the moderate height of the gasdynamic solar wind-obstacle interface and the weakness of the Martian ionosphere/atmosphere are found to be incompatible with a Venus type interaction
Directory of Open Access Journals (Sweden)
R. G.G. Pessoa et al
2015-08-01
Full Text Available The present project is part of the course in biochemistry for biomedical undergraduate students of the Federal University of Pernambuco - UFPE, which comprises theoretical and practical classes and interactive seminars prepared by students on studied topics to supplement learning. The aim of this research was to encourage students to innovate their search for knowledge, presenting an interactive strategy to demonstrate the importance of carbohydrates, as well as other energy fuels, for undergraduates students attending classes of biochemistry at the first semester at the university, in order to clarify the importance of maintaining a healthy way of life. The methodology used was a field research, documented in videos in which the opinions of a few people were registered in different places, such as in a fast-food restaurant, on the importance of carbohydrates. Records acquired were associated with a slide presentation on the subject, based on scientific books and articles, which were presented to the students of the discipline. It was also developed a dynamic to illustrate the consumption of carbohydrates in daily life and in different situations. After the project exhibition, a review of the research was conducted to the audience to express innovations or additions to their pre-existing concepts, on consumption of carbohydrates. The results of our work were very promising and the main goal of the project was achieved, since 88.2% of the respondents said there was an improvement in their knowledge, both theoretical and practical, on the subject, while only 11.8% reported no improvement at all. In conclusion, there was a greater involvement of students during the presentation of the subject and a higher participation during the group dynamic on the consumption of carbohydrates.
Wolff, Mathieu; Benhassine, Narimane; Costet, Pierre; Segu, Louis; Buhot, Marie-Christine
2004-11-01
The Morris water maze and the radial-arm maze are two of the most frequently employed behavioral tasks used to assess spatial memory in rodents. In this study, we describe two new behavioral tasks in a radial-arm water maze enabling to combine the advantages of the Morris water maze and the radial-arm maze. In both tasks, spatial and nonspatial learning was assessed and the only task parameter that varied was the nature of the information available which was either spatial (various distal extra-maze cues) or nonspatial (visual intra-maze patterns). In experiment 1, 129T2/Sv mice were able to learn three successive pairwise discriminations [(1) A+/B-, (2) B+/C-, (3) C+/A-] with the same efficiency in both modalities (i.e. spatial and nonspatial modalities). Probe-trials at the end of each of these discriminations revealed particular features of this transverse-patterning-like procedure. In experiment 2, another group of 129T2/Sv mice was submitted to a delayed matching-to-sample working memory task. Mice were able to learn the task and were then able to show resistance to temporal interference as long as 60 min in the spatial modality but they failed to acquire the task in the nonspatial modality. The fact that the nonspatial information was exactly the same in both experiments highlights the existence of an interaction between the cognitive requirements of the task and the nature of the information.
McEvoy, James P
2017-10-02
Active learning, including the promotion of student interactivity in lectures, has been found to improve student engagement and performance in university science classes. This letter describes the use of Pearson's Learning Catalytics to run regular, formatively assessed problem-solving sessions as part of the semiflipped redesign of an introductory level university bioscience course. Students found the problem-solving sessions more engaging than a traditional lecture, and felt that they were receiving better feedback on their progress in the course. Their participation in the problem-solving sessions was strongly associated with their performance in the course's summative assessments, making it possible to identify and assist probable poor performers early in the course. Other measures of student engagement with the course were not improved, and neither were their average exam grades when compared with their grades in a course which had not been redesigned. Possible reasons for this are discussed. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
Directory of Open Access Journals (Sweden)
Kawasaki Masahiro
2012-02-01
Full Text Available The plateau of 7Li abundance as a function of the iron abundance by spectroscopic observations of metal-poor halo stars (MPHSs indicates its primordial origin. The observed abundance levels are about a factor of three smaller than the primordial 7Li abundance predicted in the standard Big Bang Nucleosynthesis (BBN model. This discrepancy might originate from exotic particle and nuclear processes operating in BBN epoch. Some particle models include heavy (m >> 1 GeV long-lived colored particles which would be confined inside exotic heavy hadrons, i.e., strongly interacting massive particles (SIMPs. We have found reactions which destroy 7Be and 7Li during BBN in the scenario of BBN catalyzed by a long-lived sub-strongly interacting massive particle (sub-SIMP, X. The reactions are non radiative X captures of 7 Be and 7Li which can be operative if the X particle interacts with nuclei strongly enough to drive 7 Be destruction but not strongly enough to form a bound state with 4 He of relative angular momentum L = 1. We suggest that 7Li problem can be solved as a result of a new process beyond the standard model through which the observable signature was left on the primordial Li abundance.
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Aleksey I. Belkin
2016-03-01
Full Text Available Introduction: the article explores the interrelations between science and religion in the context of shaping integrated world outlook of future specialists in the framework of the competence-based approach. Axiological and ethical aspects of the interaction between the two major branches of human culture are considered using the example of works by Russian religious thinkers: Archbishop Luke (V. F. Voyno-Yasenetsky, V. S. Soloviev, N. A. Berdyaev. Materials and Methods: materials and methods: the study employed the method of original sources, i. e. works by N. A. Berdyaev, V. F. Voino-Yasenetsky, V. S. Solovyov, considering the problems of interaction between science and religion. The method of original sources was combined with methods of analysis, synthesis and generalisation. Results: attention is paid to different approaches to addressing this problem over the historical development of human thought. When analysing the works by V. S. Solovyov emphasis is made on the concept of integral knowledge, considering the true knowledge as a result of the interaction of rational, empirical and mystical aspects. Much attention is paid to the interpretation of Archbishop Luke’s thoughts (V. F. Voyno-Yasenetsky who advocated theoretically and practically the idea of the synthesis of the knowledge and belief in their inextricable link to the genuine scientific and philosophical works. When discussing N. A. Berdyaev’s ideas the focus is on the critical analysis of the three types of relationships between science and religion, established in human culture: 1 supremacy of knowledge and denial of faith, 2 supremacy of faith and denial of knowledge, and 3 the dualism of knowledge and faith. The article also gives a thorough account of the philosopher’s idea about the synthesis of knowledge, faith and intuition that contradicts traditional approach. The article presents the arguments of modern science about the importance of interaction between religious
International Nuclear Information System (INIS)
Safronov, A.N.; Safronov, A.A.
2006-01-01
Full text: A nonperturbative character of QCD at low and intermediate energies generates serious mathematical difficulties in describing the dynamics of hadron-hadron interactions in terms quark-gluon degrees of freedom. Therefore much effort has gone in past years into developing QCD-motivated approaches that formulate the theory of strong interaction in terms of hadron degrees of freedom. The path-integral technique together with idea of spontaneous chiral-symmetry breaking leads to Effective Field Theory (EFT) [1]. Unfortunately EFT can be applied to description of hadron-hadron interactions only at very low energies. On the other hand, meson theories of nuclear forces have long since been used to describe the properties of nucleon systems and scattering processes. Now it is not quite clear, up to what distances the meson-exchange pattern of nuclear forces is valid. Recently the new relativistic approach to the problem of constructing effective hadron-hadron interaction operators has been proposed [2-4] on the basis of analytic S-matrix theory and Gelfand-Levitan-Marchenko-Martin methods for solving the inverse quantum scattering problem. In this approach effective potential is defined as a local operator in a partial-wave equation of the quasipotential type such that it generates on-shell relativistic (Feynman) scattering amplitude that has required discontinuities at dynamical cuts. The discontinuities of partial-wave amplitudes are determined by model-independent quantities (renormalized vertex constants and amplitudes of subprocesses involving on-mass-shell particles off the physical region) and can be calculated by methods of relativistic quantum field theory within various dynamical approaches. In particular, EFT can be used to calculate the discontinuities across dynamical-cut segments closest to the physical region. In [2-4] we have examined the basic features of the proposed approach. Attention has been given primarily to analyzing the new mechanism of
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Zheng Guo
2010-01-01
Full Text Available A new virtual baffle methodology is implemented to solve contact/detach problem which is often encountered in fluid and structure interaction simulations while using dynamic grids technique. The algorithm is based on tetrahedral unstructured grid, and a zero thickness baffle face is generated between actually contacted two objects. In computation process, this baffle face is divided into two parts representing convective and blocked area, respectively; the area of each part is calculated according to the actual displacement between the two objects. Convective part in a baffle face is treated as inner interface between cells, and on blocked part wall boundary condition is applied; so convective and blocking effect can be achieved on a single baffle face. This methodology can simulate real detaching process starting from contact, that is, zero displacement, while it has no restriction to minimum grid cell size. The methodology is then applied in modeling of a complicated safety valve opening process, involving multidisciplinary fluid and structure interaction and dynamic grids. The results agree well with experimental data, which proves that the virtual baffle method is successful.
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Helga Loos
2004-12-01
Full Text Available Partindo de uma perspectiva construtivista e interacionista, pesquisadores têm apontado o conflito sócio-cognitivo como situação que favorece o desenvolvimento cognitivo em estudantes que resolvem problemas conjuntamente. Com base no pressuposto de que elementos afetivos estão interligados aos sociais e cognitivos, o estudo teve por objetivo observar como oito duplas de estudantes de sexta e sétima séries gerenciavam, simultaneamente, a busca de solução para quatro problemas algébricos, a relação interpessoal e a ansiedade gerada pelas dificuldades eventualmente encontradas. As sessões foram videografadas e analisadas qualitativamente. Observou-se que: (1 todas as duplas manifestaram ansiedade relacionada às dificuldades da tarefa; (2 uma boa interação facilitou o gerenciamento dessa ansiedade; (3 uma má interação piorou o desempenho, sendo fonte adicional de ansiedade e desencorajando o desencadeamento de conflitos sócio-cognitivos; (4 uma boa interação e um gerenciamento adequado da ansiedade não puderam garantir um bom desempenho na tarefa quando, a pelo menos um dos participantes, faltavam os requisitos cognitivos mínimos para dominá-la.From a constructionist and interactionist perspective, researchers have shown that the socio-cognitive conflict leads to a cognitive development by students in solving-problem tasks in small groups. Based on the paradigm that affective factors are interconnected to the social and cognitive ones, this study aimed to observe sixteen 6th and 7th grade students in working in pairs, how they manage simultaneously: the solution search to four given algebraic problems, the interpersonal relationship and the anxiety generated by the difficulties eventually found. The sessions were recorded in video and qualitatively analyzed. It was observed that: (1 all groups manifested anxiety related to the difficulties of the task; (2 good interactions facilitated anxiety management; (3 bad interactions
Misund, Aud R; Bråten, Stein; Nerdrum, Per; Pripp, Are Hugo; Diseth, Trond H
2016-01-01
Objective Pregnancy, birth and health complications, maternal mental health problems following preterm birth and their possible impact on early mother–infant interaction at 6 and 18 months corrected age (CA) were explored. Predictors of mother–infant interaction at 18 months CA were identified. Design and methods This prospective longitudinal and observational study included 33 preterm mother–infant (interactions at 6 and 18 months CA from a socioeconomic low-risk, middle-class sample. The Parent–Child Early Relational Assessment (PCERA) scale was used to assess the mother–infant interaction. Results ‘Bleeding in pregnancy’ predicted lower quality in preterm mother–infant interaction in 6 PCERA scales, while high ‘maternal trait anxiety’ predicted higher interactional quality in 2 PCERA scales and ‘family size’ predicted lower interactional quality in 1 PCERA scale at 18 months CA. Mothers with symptoms of post-traumatic stress reactions, general psychological distress and anxiety at 2 weeks postpartum (PP) showed significantly better outcome than mothers without symptoms in 6 PCERA subscales at 6 months CA and 2 PCERA subscales at 18 months CA. Conclusions Our study detected a correspondence between early pregnancy complications and lower quality of preterm mother–infant interaction, and an association between high levels of maternal mental health problems and better quality in preterm mother–infant interaction. PMID:27147380
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Moldovan Laura
2010-10-01
Full Text Available Abstract Background Computer-based teaching (CBT is a well-known educational device, but it has never been applied systematically to the teaching of a complex, rare, genetic disease, such as Hunter disease (MPS II. Aim To develop interactive teaching software functioning as a virtual clinic for the management of MPS II. Implementation and Results The Hunter disease eClinic, a self-training, user-friendly educational software program, available at the Lysosomal Storage Research Group (http://www.lysosomalstorageresearch.ca, was developed using the Adobe Flash multimedia platform. It was designed to function both to provide a realistic, interactive virtual clinic and instantaneous access to supporting literature on Hunter disease. The Hunter disease eClinic consists of an eBook and an eClinic. The eClinic is the interactive virtual clinic component of the software. Within an environment resembling a real clinic, the trainee is instructed to perform a medical history, to examine the patient, and to order appropriate investigation. The program provides clinical data derived from the management of actual patients with Hunter disease. The eBook provides instantaneous, electronic access to a vast collection of reference information to provide detailed background clinical and basic science, including relevant biochemistry, physiology, and genetics. In the eClinic, the trainee is presented with quizzes designed to provide immediate feedback on both trainee effectiveness and efficiency. User feedback on the merits of the program was collected at several seminars and formal clinical rounds at several medical centres, primarily in Canada. In addition, online usage statistics were documented for a 2-year period. Feedback was consistently positive and confirmed the practical benefit of the program. The online English-language version is accessed daily by users from all over the world; a Japanese translation of the program is also available. Conclusions The
Al-Jasmi, Fatma; Moldovan, Laura; Clarke, Joe T R
2010-10-25
Computer-based teaching (CBT) is a well-known educational device, but it has never been applied systematically to the teaching of a complex, rare, genetic disease, such as Hunter disease (MPS II). To develop interactive teaching software functioning as a virtual clinic for the management of MPS II. The Hunter disease eClinic, a self-training, user-friendly educational software program, available at the Lysosomal Storage Research Group (http://www.lysosomalstorageresearch.ca), was developed using the Adobe Flash multimedia platform. It was designed to function both to provide a realistic, interactive virtual clinic and instantaneous access to supporting literature on Hunter disease. The Hunter disease eClinic consists of an eBook and an eClinic. The eClinic is the interactive virtual clinic component of the software. Within an environment resembling a real clinic, the trainee is instructed to perform a medical history, to examine the patient, and to order appropriate investigation. The program provides clinical data derived from the management of actual patients with Hunter disease. The eBook provides instantaneous, electronic access to a vast collection of reference information to provide detailed background clinical and basic science, including relevant biochemistry, physiology, and genetics. In the eClinic, the trainee is presented with quizzes designed to provide immediate feedback on both trainee effectiveness and efficiency. User feedback on the merits of the program was collected at several seminars and formal clinical rounds at several medical centres, primarily in Canada. In addition, online usage statistics were documented for a 2-year period. Feedback was consistently positive and confirmed the practical benefit of the program. The online English-language version is accessed daily by users from all over the world; a Japanese translation of the program is also available. The Hunter disease eClinic employs a CBT model providing the trainee with realistic
International Nuclear Information System (INIS)
Yelnik, J.-B.
1978-06-01
The purpose of this work mainly consisted in (a) taking into account all the orders of the atom-radiation interaction (in a low intensity field) for strictly processing the natural enlargement over the entire spectral domain of the line and (b) simultaneously applying the unified theories of the collision enlargement to the radiation distribution problem. These redistribution formulae also drawn up by Nienhuis et al. were supposed to apply also outside the impact domain. However, it was soon realised that these results were not satisfactory since, in certain cases (observation in the wings and excitation in the centre or vice-versa), they could give rise to a negative fluorescence profile. This drawback was due to the approximation consisting in disregarding the effect of the radiative processes throughout the duration of a collision. An accurate treatment of the redistribution that no longer makes use of the incriminated approximation is presented in the appendix. In this way, new results are obtained which no longer exhibit the irregularities of those obtained in the preceding treatment and which apply from the centre of the line to the near-by quasi-static domain [fr
Ellaway, Rachel H; Round, Jonathan; Vaughan, Sophie; Poulton, Terry; Zary, Nabil
2015-01-01
Background The impact of the use of video resources in primarily paper-based problem-based learning (PBL) settings has been widely explored. Although it can provide many benefits, the use of video can also hamper the critical thinking of learners in contexts where learners are developing clinical reasoning. However, the use of video has not been explored in the context of interactive virtual patients for PBL. Objective A pilot study was conducted to explore how undergraduate medical students interpreted and evaluated information from video- and text-based materials presented in the context of a branched interactive online virtual patient designed for PBL. The goal was to inform the development and use of virtual patients for PBL and to inform future research in this area. Methods An existing virtual patient for PBL was adapted for use in video and provided as an intervention to students in the transition year of the undergraduate medicine course at St George’s, University of London. Survey instruments were used to capture student and PBL tutor experiences and perceptions of the intervention, and a formative review meeting was run with PBL tutors. Descriptive statistics were generated for the structured responses and a thematic analysis was used to identify emergent themes in the unstructured responses. Results Analysis of student responses (n=119) and tutor comments (n=18) yielded 8 distinct themes relating to the perceived educational efficacy of information presented in video and text formats in a PBL context. Although some students found some characteristics of the videos beneficial, when asked to express a preference for video or text the majority of those that responded to the question (65%, 65/100) expressed a preference for text. Student responses indicated that the use of video slowed the pace of PBL and impeded students’ ability to review and critically appraise the presented information. Conclusions Our findings suggest that text was perceived to be a
Woodham, Luke A; Ellaway, Rachel H; Round, Jonathan; Vaughan, Sophie; Poulton, Terry; Zary, Nabil
2015-06-18
The impact of the use of video resources in primarily paper-based problem-based learning (PBL) settings has been widely explored. Although it can provide many benefits, the use of video can also hamper the critical thinking of learners in contexts where learners are developing clinical reasoning. However, the use of video has not been explored in the context of interactive virtual patients for PBL. A pilot study was conducted to explore how undergraduate medical students interpreted and evaluated information from video- and text-based materials presented in the context of a branched interactive online virtual patient designed for PBL. The goal was to inform the development and use of virtual patients for PBL and to inform future research in this area. An existing virtual patient for PBL was adapted for use in video and provided as an intervention to students in the transition year of the undergraduate medicine course at St George's, University of London. Survey instruments were used to capture student and PBL tutor experiences and perceptions of the intervention, and a formative review meeting was run with PBL tutors. Descriptive statistics were generated for the structured responses and a thematic analysis was used to identify emergent themes in the unstructured responses. Analysis of student responses (n=119) and tutor comments (n=18) yielded 8 distinct themes relating to the perceived educational efficacy of information presented in video and text formats in a PBL context. Although some students found some characteristics of the videos beneficial, when asked to express a preference for video or text the majority of those that responded to the question (65%, 65/100) expressed a preference for text. Student responses indicated that the use of video slowed the pace of PBL and impeded students' ability to review and critically appraise the presented information. Our findings suggest that text was perceived to be a better source of information than video in virtual
Galindo Torres, S. A.; Scheuermann, A.; Ruest, M.
2016-12-01
Air blasts that may occur in a block caving mining operation represent a significant hazard for personnel as well as to mining infrastructure. Uncontrolled caving of a large volume of broken rock into a mine void causes compression of the air within, forcing it to flow at high velocities into connecting tunnels such as extraction points beneath the cave or observation points intersecting the cave. This high velocity flow of air can cause injury to personnel and significant damage to equipment. In this presentation, we introduce a simulation engine for the air blast problem. The solid material is modelled using the Discrete Element Method (DEM) and the fluid (air) is modelled using the Lattice Boltzmann Method (LBM). The combined DEM-LBM approach has been introduced by our group at the University of Queensland[1]. LBM allows us to introduce an appropriate equation of state for the air that simulates compressibility as a function of the speed of sound. Validation examples are presented to justify the use of this tool for an air blasting situation. A section view of one simulation is provided in Fig 1. An investigation into the risk of developing air pockets as a function of fragment size distribution is also conducted and described. The fragment size distribution can be assessed during mining and the risk of air pockets forming (and consequently of air blast occurring) can be deduced and mitigation measures put in place. The effect of other key variables that can be determined from geotechnical investigations, such as fracture frequency, are also systematically explored. It is expected that the results of this study can elucidate key features of the air blasting phenomenon in order to formulate safer mining protocols. references 1. Galindo-Torres, S.A., A coupled Discrete Element Lattice Boltzmann Method for the simulation of fluid-solid interaction with particles of general shapes. Computer Methods in Applied Mechanics and Engineering, 2013. 265(0): p. 107-119.
Rajan, Shobana; Khanna, Ashish; Argalious, Maged; Kimatian, Stephen J; Mascha, Edward J; Makarova, Natalya; Nada, Eman M; Elsharkawy, Hesham; Firoozbakhsh, Farhad; Avitsian, Rafi
2016-02-01
Simulation-based learning is emerging as an alternative educational tool in this era of a relative shortfall of teaching anesthesiologists. The objective of the study is to assess whether screen-based (interactive computer simulated) case scenarios are more effective than problem-based learning discussions (PBLDs) in improving test scores 4 and 8 weeks after these interventions in anesthesia residents during their first neuroanesthesia rotation. Prospective, nonblinded quasi-crossover study. Cleveland Clinic. Anesthesiology residents. Two case scenarios were delivered from the Anesoft software as screen-based sessions, and parallel scripts were developed for 2 PBLDs. Each resident underwent both types of training sessions, starting with the PBLD session, and the 2 cases were alternated each month (ie, in 1 month, the screen-based intervention used case 1 and the PBLD used case 2, and vice versa for the next month). Test scores before the rotation (baseline), immediately after the rotation (4 weeks after the start of the rotation), and 8 weeks after the start of rotation were collected on each topic from each resident. The effect of training method on improvement in test scores was assessed using a linear mixed-effects model. Compared to the departmental standard of PBLD, the simulation method did not improve either the 4- or 8-week mean test scores (P = .41 and P = .40 for training method effect on 4- and 8-week scores, respectively). Resident satisfaction with the simulation module on a 5-point Likert scale showed subjective evidence of a positive impact on resident education. Screen-based simulators were not more effective than PBLD for education during the neuroanesthesia rotation in anesthesia residency. Copyright © 2016 Elsevier Inc. All rights reserved.
Marsman, Rianne; Oldehinkel, Albertine J.; Ormel, Johan; Buitelaar, Jan K.
2013-01-01
Although externalizing behavior problems show in general a high stability over time, the course of externalizing behavior problems may vary from individual to individual. Our main goal was to investigate the predictive role of parenting on externalizing behavior problems. In addition, we
Ozdemir, S.; Reis, Z. Ayvaz
2013-01-01
Mathematics is an important discipline, providing crucial tools, such as problem solving, to improve our cognitive abilities. In order to solve a problem, it is better to envision and represent through multiple means. Multiple representations can help a person to redefine a problem with his/her own words in that envisioning process. Dynamic and…
Angeli, Charoula
2013-01-01
An investigation was carried out to examine the effects of cognitive style on learners' performance and interaction during complex problem solving with a computer modeling tool. One hundred and nineteen undergraduates volunteered to participate in the study. Participants were first administered a test, and based on their test scores they were…
Frezzotti, M.L.; Zavon, V.; Peccerillo, A.; Nikogosian, I.
2002-01-01
Silica-rich melts in quartz xenoliths from Vulcano islands and their bearing on processes of crustal melting and crust-magma interaction in the Aeolian Arc, Italy Proceedings of workshop Melt inclusion: methods, applications and problem. Napoli, Italy, September 2002, p. 71-73
Energy Technology Data Exchange (ETDEWEB)
Tanaka, Masaaki, E-mail: tanaka.masaaki@jaea.go.jp
2014-11-15
Highlights: • Outline of numerical simulation code MUGTHES for fluid-structure thermal interaction was described. • The grid convergence index (GCI) method was applied according to the ASME V and V-20 guide. • Uncertainty of MUGTHES can be successfully quantified for thermal-hydraulic problems and unsteady heat conduction problems in the structure. • Validation for fluid-structure thermal interaction problem in a T-junction piping system was well conducted. - Abstract: Thermal fatigue caused by thermal mixing phenomena is one of the most important issues in design and safety assessment of fast breeder reactors. A numerical simulation code MUGTHES consisting of two calculation modules for unsteady thermal-hydraulics analysis and unsteady heat conduction analysis in structure has been developed to predict thermal mixing phenomena and to estimate thermal response of structure under the thermal interaction between fluid and structure fields. Although verification and validation (V and V) of MUGTHES has been required, actual procedure for uncertainty quantification is not fixed yet. In order to specify an actual procedure of V and V, uncertainty quantifications with the grid convergence index (GCI) estimation according to the existing guidelines were conducted in fundamental laminar flow problems for the thermal-hydraulics analysis module, and also uncertainty for the structure heat conduction analysis module and conjugate heat transfer model was quantified in comparison with the theoretical solutions of unsteady heat conduction problems. After the verification, MUGTHES was validated for a practical fluid-structure thermal interaction problem in T-junction piping system compared with measured results of velocity and temperatures of fluid and structure. Through the numerical simulations in the verification and validation, uncertainty of the code was successfully estimated and applicability of the code to the thermal fatigue issue was confirmed.
Misund, Aud R; Bråten, Stein; Nerdrum, Per; Pripp, Are Hugo; Diseth, Trond H
2016-05-04
Pregnancy, birth and health complications, maternal mental health problems following preterm birth and their possible impact on early mother-infant interaction at 6 and 18 months corrected age (CA) were explored. Predictors of mother-infant interaction at 18 months CA were identified. This prospective longitudinal and observational study included 33 preterm mother-infant (interactions at 6 and 18 months CA from a socioeconomic low-risk, middle-class sample. The Parent-Child Early Relational Assessment (PCERA) scale was used to assess the mother-infant interaction. 'Bleeding in pregnancy' predicted lower quality in preterm mother-infant interaction in 6 PCERA scales, while high 'maternal trait anxiety' predicted higher interactional quality in 2 PCERA scales and 'family size' predicted lower interactional quality in 1 PCERA scale at 18 months CA. Mothers with symptoms of post-traumatic stress reactions, general psychological distress and anxiety at 2 weeks postpartum (PP) showed significantly better outcome than mothers without symptoms in 6 PCERA subscales at 6 months CA and 2 PCERA subscales at 18 months CA. Our study detected a correspondence between early pregnancy complications and lower quality of preterm mother-infant interaction, and an association between high levels of maternal mental health problems and better quality in preterm mother-infant interaction. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/
International Nuclear Information System (INIS)
Osman, A.; Ramadan, S.
1989-01-01
Faddeev equations of bound three-nucleon system are presented as a set of integral equations. To solve them, a sutable form of the nucleon-nucleon interactions is used: with the exchange of a scalar meson, a pseudoscalar meson and a massless vector meson. Higher orders of these different meson exchanges in the nucleon-nucleon interactions have been taken into account. With these nuclear forces and nucleon-nucleon interactions, the three-nucleon binding energy is calculated by solving the Faddeev integral equations. The obtained value of the three-nucleon binding energy is 8.441 MeV. The inclusion of the higher order terms of the different meson exchange in the nuclear nucleon-nucleon interaction is found to affect the three-nucleon binding by about 3.92%. 3 figs., 16 refs
Directory of Open Access Journals (Sweden)
Tunna Baruah
2012-04-01
Full Text Available Calculating electron-vibration (vibronic interaction constants is computationally expensive. For molecules containing N nuclei it involves solving the Schrödinger equation for Ο(3N nuclear configurations in addition to the cost of determining the vibrational modes. We show that quantum vibronic interactions are proportional to the classical atomic forces induced when the total charge of the system is varied. This enables the calculation of vibronic interaction constants from O(1 solutions of the Schrödinger equation. We demonstrate that the O(1 approach produces numerically accurate results by calculating the vibronic interaction constants for several molecules. We investigate the role of molecular vibrations in the Mott transition in κ-(BEDT-TTF2Cu[N(CN2]Br.
Sahar Mohamadi; Sayedeh Maryam Hosseiny; Sayedeh Sana Hosseiny
2016-01-01
Introduction: Today, due to the speed and amount of science production in the world, knowledge processing and learning is changing. In this regard, independent learning using new instructional methods interactively with a specific goal in order to dominate the content and assignments with self-regulation strategies is of great importance. This study is aimed to evaluate interactive e-learning role on medical students’ learning in psychology courses. Methods: This study is a experimental r...
... often, it could be a sign of a balance problem. Balance problems can make you feel unsteady. You may ... related injuries, such as a hip fracture. Some balance problems are due to problems in the inner ...
[Population problem, comprehension problem].
Tallon, F
1993-08-01
Overpopulation of developing countries in general, and Rwanda in particular, is not just their problem but a problem for developed countries as well. Rapid population growth is a key factor in the increase of poverty in sub-Saharan Africa. Population growth outstrips food production. Africa receives more and more foreign food, economic, and family planning aid each year. The Government of Rwanda encourages reduced population growth. Some people criticize it, but this criticism results in mortality and suffering. One must combat this ignorance, but attitudes change slowly. Some of these same people find the government's acceptance of family planning an invasion of their privacy. Others complain that rich countries do not have campaigns to reduce births, so why should Rwanda do so? The rate of schooling does not increase in Africa, even though the number of children in school increases, because of rapid population growth. Education is key to improvements in Africa's socioeconomic growth. Thus, Africa, is underpopulated in terms of potentiality but overpopulated in terms of reality, current conditions, and possibilities of overexploitation. Africa needs to invest in human resources. Families need to save, and to so, they must refrain from having many children. Africa should resist the temptation to waste, as rich countries do, and denounce it. Africa needs to become more independent of these countries, but structural adjustment plans, growing debt, and rapid population growth limit national independence. Food aid is a means for developed countries to dominate developing countries. Modernization through foreign aid has had some positive effects on developing countries (e.g., improved hygiene, mortality reduction), but these also sparked rapid population growth. Rwandan society is no longer traditional, but it is also not yet modern. A change in mentality to fewer births, better quality of life for living infants, better education, and less burden for women must occur
International Nuclear Information System (INIS)
Safronov, A.N.
2007-01-01
Full text: The pion-nucleon dynamics is one of the most fundamental problems in nuclear and particle physics. It is now widely believed that QCD is fundamental theory of strong interactions. On this basis all hadron-hadron interactions are completely determined by the underlying quark-gluon dynamics. However, due to the formidable mathematical problems raised by the non-perturbative character of QCD at low and intermediate energies, we are still far from a quantitative understanding hadron-hadron interactions from this point of view. Recently the relativistic approaches to constructing effective interaction operators between strongly interacting composite particles has been proposed on the basis of analytic S-matrix theory and methods for solving the inverse quantum scattering problem. The kernel of Marchenko equation in theory of inverse scattering problem can be expressed in terms of the discontinuity of the partial wave amplitude on dynamic cut in the complex s=k 2 plane, k being the relative momentum of colliding particles. The discontinuities of partial-wave amplitudes are determined by model-independent quantities (renormalized vertex constants and amplitudes of sub-processes involving on-mass-shell particles off physical region) and can be calculated by methods of relativistic quantum field theory within various dynamical approaches. In particular, effective field theory can be used to calculate the discontinuities across dynamical cuts closest to physical region. In present work a new manifestly Poincare-invariant approach to solving the inverse scattering problem is developed with allowance for inelasticity effects. The equations of the N/D method are used as dynamical equations in this approach. With the help of N/D-equations it was earlier shown that solution of a scattering problem in case of nonzero angular momentum does not exist for arbitrary discontinuity of partial-wave amplitude. The method is elaborated allowing to determine contributions of
International Nuclear Information System (INIS)
Ogava, S.; Savada, S.; Nakagava, M.
1983-01-01
The problem of the use of weak interaction laws to study models of elementary particles is discussed. The most typical examples of weak interaction is beta-decay of nucleons and muons. Beta-interaction is presented by quark currents in the form of universal interaction of the V-A type. Universality of weak interactions is well confirmed using as examples e- and μ-channels of pion decay. Hypothesis on partial preservation of axial current is applicable to the analysis of processes with pion participation. In the framework of the model with four flavours lepton decays of hadrons are considered. Weak interaction without lepton participation are also considered. Properties of neutral currents are described briefly
Problems of high energy physics
International Nuclear Information System (INIS)
Kadyshevskij, V.G.
1989-01-01
Some problems of high energy physics are discussed. The main attention is paid to describibg the standard model. The model comprises quantum chromodynamics and electroweak interaction theory. The problem of CP breaking is considered as well. 8 refs.; 1 tab
Czech Academy of Sciences Publication Activity Database
Hundertmark-Zaušková, A.; Lukáčová-Medviďová, M.; Nečasová, Šárka
2016-01-01
Roč. 68, č. 1 (2016), s. 193-243 ISSN 0025-5645 R&D Projects: GA ČR(CZ) GAP201/11/1304 Institutional support: RVO:67985840 Keywords : non-Newtonian fluids * fluid-structure interaction * shear-thinning fluids Subject RIV: BA - General Mathematics Impact factor: 0.592, year: 2016 http://projecteuclid.org/euclid.jmsj/1453731541
2014-08-01
enhances flow incompressibility [20]. This correction takes into account the velocity of neighboring markers through a mean velocity evaluated within...interactions between individual markers; i.e., the right hand side of Eqs. (7) and (8), are accounted for, the total rigid body force and torque due to the...coordinate formulation. In: Proceedings of the ASME 2005 IDETC/ CIE . Orlando, Florida (2005). [35] Shabana A.: Flexible multibody dynamics: Review of
... Staying Safe Videos for Educators Search English Español Speech Problems KidsHealth / For Teens / Speech Problems What's in ... a person's ability to speak clearly. Some Common Speech and Language Disorders Stuttering is a problem that ...
Directory of Open Access Journals (Sweden)
Muhammad Aslam Noor
2004-01-01
Full Text Available We consider a new class of equilibrium problems, known as hemiequilibrium problems. Using the auxiliary principle technique, we suggest and analyze a class of iterative algorithms for solving hemiequilibrium problems, the convergence of which requires either pseudomonotonicity or partially relaxed strong monotonicity. As a special case, we obtain a new method for hemivariational inequalities. Since hemiequilibrium problems include hemivariational inequalities and equilibrium problems as special cases, the results proved in this paper still hold for these problems.
2014-08-01
Thiscorrection takes into account the velocity of neighboring mark-ers through a mean velocity evaluated within the support of anominal marker a as v̂a...right hand side of Eqs. (7) and (8), are accounted for,the total rigid body force and torque due to the interaction withthe fluid can be obtained by...absolute nodal coordinate formulation. In: Pro-ceedings of the ASME 2005 IDETC/ CIE , Orlando, FL, USA.American Society of Mechanical Engineers (2005)[35
LENUS (Irish Health Repository)
Corrigan, Mark
2012-02-03
Information technology has the potential to transform surgical education. Combining symbolic, iconic, and enactive teaching modalities to construct an authentic conceptual model potentially can transform a primarily didactic learning experience into an interactive Web-enhanced one. This study sought to assess the introduction of a Web-based module to complement traditional surgical undergraduate curricula. Adopting the clinical case as its fundamental educational approach, an online resource simulating surgical clinical decision making ("SURGENT," http:\\/\\/www.surgent.ie) was developed, which consists of the interpretation of clinical photographs, laboratory data, and X-rays as well as the formulation of a management plan. Evaluation was in both a qualitative and a quantitative fashion. An anonymous postcourse survey (73% response) of 117 final medical students was used to by researchers to evaluate access, process, and outcome criteria. SURGENT was used by 98% of students, with 69% spending more than 30 minutes per session on the program. First-class honors in the final surgical clinical examination improved from 11% to 20% (p = 0.01) as compared with the previous control year. A Web-enhanced interactive surgical module in an undergraduate course can convey successfully information and understanding beyond the textbook. It is intended that SURGENT will supplement textbooks and ward experience, allowing students to develop their clinical decision-making skills.
Directory of Open Access Journals (Sweden)
Sebastián A. Ballari
2016-06-01
Full Text Available Although the co-occurrence of nonnative vertebrates is a ubiquitous global phenomenon, the study of interactions between invaders is poorly represented in the literature. Limited understanding of the interactions between co-occurring vertebrates can be problematic for predicting how the removal of only one invasive—a common management scenario—will affect native communities. We suggest a trophic food web framework for predicting the effects of single-species management on native biodiversity. We used a literature search and meta-analysis to assess current understanding of how the removal of one invasive vertebrate affects native biodiversity relative to when two invasives are present. The majority of studies focused on the removal of carnivores, mainly within aquatic systems, which highlights a critical knowledge gap in our understanding of co-occurring invasive vertebrates. We found that removal of one invasive vertebrate caused a significant negative effect on native species compared to when two invasive vertebrates were present. These unexpected results could arise because of the positioning and hierarchy of the co-occurring invasives in the food web (e.g., carnivore–carnivore or carnivore–herbivore. We consider that there are important knowledge gaps to determinate the effects of multiple co-existing invaders on native ecosystems, and this information could be precious for management.
Ballari, Sebastián A; Kuebbing, Sara E; Nuñez, Martin A
2016-01-01
Although the co-occurrence of nonnative vertebrates is a ubiquitous global phenomenon, the study of interactions between invaders is poorly represented in the literature. Limited understanding of the interactions between co-occurring vertebrates can be problematic for predicting how the removal of only one invasive-a common management scenario-will affect native communities. We suggest a trophic food web framework for predicting the effects of single-species management on native biodiversity. We used a literature search and meta-analysis to assess current understanding of how the removal of one invasive vertebrate affects native biodiversity relative to when two invasives are present. The majority of studies focused on the removal of carnivores, mainly within aquatic systems, which highlights a critical knowledge gap in our understanding of co-occurring invasive vertebrates. We found that removal of one invasive vertebrate caused a significant negative effect on native species compared to when two invasive vertebrates were present. These unexpected results could arise because of the positioning and hierarchy of the co-occurring invasives in the food web (e.g., carnivore-carnivore or carnivore-herbivore). We consider that there are important knowledge gaps to determinate the effects of multiple co-existing invaders on native ecosystems, and this information could be precious for management.
Chudnovsky, A.; Dolgopolsky, A.; Kachanov, M.
1987-01-01
The elastic interactions of a two-dimensional configuration consisting of a crack with an array of microcracks located near the tip are studied. The general form of the solution is based on the potential representations and approximations of tractions on the microcracks by polynomials. In the second part, the technique is applied to two simple two-dimensional configurations involving one and two microcracks. The problems of stress shielding and stress amplification (the reduction or increase of the effective stress intensity factor due to the presence of microcracks) are discussed, and the refinements introduced by higher order polynomial approximations are illustrated.
Directory of Open Access Journals (Sweden)
Astrid Jensen
2012-09-01
Full Text Available This article focuses on opportunities for citizens to interact with public organisations in the processing of individual cases and how this interaction is facilitated by the Internet. We analysed a string of messages from the online forum of the non-governmental organisation Marriage without Borders, which offers dialogue-based advice to members looking for help prior with the complex application process in relation to family reunification visas in Denmark. The trajectory of the problem-solving interaction clearly demonstrates the Internet’s potential for dynamic online interaction, emphasising the timeliness of a joint accomplishment. Our findings also emphasise the potential of non-governmental web forums to address the needs of member publics and to serve as equalisers in relation to the power gap between the more powerful public authorities and the less powerful individuals. A recurrent theme running through these posts is that you trust the members of the community to help as best they can and that expertise is not allocated to the authorities alone.
International Nuclear Information System (INIS)
EI-Shorbagy, Kh.H.
2002-11-01
The stabilization effect of a strong HP electric field on beam-plasma instability in a cylindrical warm plasma waveguide is discussed. A new mathematical technique 'separation method' which has been applied to the two-fluid plasma model to separate the equations, which describe the system, into two parts, temporal and space parts. Plasma electrons are considered to have a thermal velocity. It is shown that a HF electric field has no essential influence on dispersion characteristics of unstable surface waves excited in a warm plasma waveguide by a low-density electron beam. The region of instability only slightly narrowing and the growth rate decreases by a small parameter and this result has been reduced compared to cold plasma. Also, it is found that the plasma electrons have not affected the solution of the space part of the problem. (author)
Chapanis, A.; Ochsman, R. B.; Parrish, R. N.; Weeks, G. D.
1972-01-01
Two-man teams solved credible, 'real-world' problems for which computer assistance has been or could be useful. Conversations were carried on in one of four modes of communication: (1) typewriting, (2) handwriting, (3) voice, and (4) natural, unrestricted communication. Two groups of subjects (experienced and inexperienced typists) were tested in the typewriting mode. Performance was assessed on three classes of dependent measures: time to solution, behavioral measures of activity, and linguistic measures. Significant and meaningful differences among the communication modes were found in each of the three classes of dependent variable. This paper is concerned mainly with the results of the activity analyses. Behavior was recorded in 15 different categories. The analyses of variance yielded 34 statistically significant terms of which 27 were judged to be practically significant as well. When the data were transformed to eliminate heterogeneity, the analyses of variance yielded 35 statistically significant terms of which 26 were judged to be practically significant.
Explaining the Mind: Problems, Problems
Harnad, Stevan
2001-01-01
The mind/body problem is the feeling/function problem: How and why do feeling systems feel? The problem is not just "hard" but insoluble (unless one is ready to resort to telekinetic dualism). Fortunately, the "easy" problems of cognitive science (such as the how and why of categorization and language) are not insoluble. Five books (by Damasio, Edelman/Tononi...
Directory of Open Access Journals (Sweden)
Tyaglov Sergey, G.
2015-03-01
Full Text Available In the context of Russia's transition to innovation-oriented type of economic development is becoming particularly urgent problem of improving the quality of the workforce and professional development throughout their working life. Currently, the regional labor market characterized by increasing diversity of professions and as a result, the diversification requirements of employers at the regional level, depending on the industrial, agricultural, logistics, etc. specialization of the region. The increasing complexity of the structure and the internal differentiation of the various areas of economic activity determines the demand for workers with a broad fundamental training along with narrow professional competencies, so the mechanism of regulation of the regional bloc needs assessment of competencies of workers, institutionalized at both the state level and at the level of regional public associations, employers' associations. Particular attention is paid to the analysis of the state of the youth segment of the labor market, the establishment of the fact that for resolving the contradictions of the labor market and the education market (mismatch structure and quality of the training of human capital in the region, the needs of employers, the contradictions of regional professional and educational standards at the regional level, it is advisable to provide correlation of regional professional standards with the federal state educational standards, which will neutralize the contradictions, the solution of which determines the rational use of the labor potential in the regional economy.
... know the exact cause of your prostate problem. Prostatitis The cause of prostatitis depends on whether you ... prostate problem in men older than age 50. Prostatitis If you have a UTI, you may be ...
International Nuclear Information System (INIS)
2005-01-01
This article presents the general problems as natural disasters, consequences of global climate change, public health, the danger of criminal actions, the availability to information about problems of environment
... Staying Safe Videos for Educators Search English Español Learning Problems KidsHealth / For Kids / Learning Problems What's in ... for how to make it better. What Are Learning Disabilities? Learning disabilities aren't contagious, but they ...
... Read MoreDepression in Children and TeensRead MoreBMI Calculator Ankle ProblemsFollow this chart for more information about problems that can cause ankle pain. Our trusted Symptom Checker is written and ...
Improving mathematical problem solving : A computerized approach
Harskamp, EG; Suhre, CJM
Mathematics teachers often experience difficulties in teaching students to become skilled problem solvers. This paper evaluates the effectiveness of two interactive computer programs for high school mathematics problem solving. Both programs present students with problems accompanied by instruction
DEFF Research Database (Denmark)
Christensen, Anders Bøggild; Rasmussen, Tove; Bundesen, Peter Verner
Sociale problemer kan betragtes som selve udgangspunktet for socialt arbejde, hvor ambitionen er at råde bod på problemerne og sikre, at udsatte borgere får en bedre tilværelse. Det betyder også, at diskussionen af sociale problemer er afgørende for den sociale grundfaglighed. I denne bog sætter en...... række fagfolk på tværs af det danske socialfaglige felt fokus på sociale problemer. Det diskuteres, hvad vi overhovedet forstår ved sociale problemer, hvordan de opstår, hvilke konsekvenser de har, og ikke mindst hvordan man som fagprofessionel håndterer sociale problemer i det daglige arbejde. Bogen er...... skrevet som lærebog til professionsuddannelser, hvor sociale problemer udgør en dimension, bl.a. socialrådgiver-, pædagog- og sygeplejerskeuddannelserne....
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.
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)
... Read MoreDepression in Children and TeensRead MoreBMI Calculator Hearing ProblemsLoss in the ability to hear or discriminate ... This flow chart will help direct you if hearing loss is a problem for you or a ...
An isoperimetric problem for point interactions
Czech Academy of Sciences Publication Activity Database
Exner, Pavel
2005-01-01
Roč. 38, č. 22 (2005), s. 4795-4802 ISSN 0305-4470 R&D Projects: GA AV ČR KSK1010104 Institutional research plan: CEZ:AV0Z1048901 Keywords : eigenvalues * Laplacians Subject RIV: BE - Theoretical Physics Impact factor: 1.566, year: 2005
Šilhavá, Marie
2009-01-01
This diploma thesis concentrates on problem posing from the students' point of view. Problem posing can be either seen as a teaching method which can be used in the class, or it can be used as a tool for researchers or teachers to assess the level of students' understanding of the topic. In my research, I compare three classes, one mathematics specialist class and two generalist classes, in their ability of problem posing. As an assessment tool it seemed that mathemathics specialists were abl...
DEFF Research Database (Denmark)
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 empirical studies on Danish youth career guidance were included in the study. An analysis of the issues in focus resulted in nine problem categories. One of these, ‘targeting’, is analysed using the WPR approach. Finally, the article concludes that the WPR approach...... provides a constructive basis for a critical analysis and discussion of the collective empirical knowledge production on career guidance, stimulating awareness of problems and potential solutions among the career guidance community....
... For Consumers Consumer Information by Audience For Women Sleep Problems Share Tweet Linkedin Pin it More sharing ... 101 KB) En Español Medicines to Help You Sleep Tips for Better Sleep Basic Facts about Sleep ...
... such as sores, are very common. Follow this chart for more information about mouth problems in adults. ... cancers. See your dentist if sharp or rough teeth or dental work are causing irritation. Start OverDiagnosisThis ...
... our e-newsletter! Aging & Health A to Z Kidney Problems Basic Facts & Information The kidneys are two ... kidney (renal) diseases are called nephrologists . What are Kidney Diseases? For about one-third of older people, ...
Kellerer, Hans; Pisinger, David
2004-01-01
Thirteen years have passed since the seminal book on knapsack problems by Martello and Toth appeared. On this occasion a former colleague exclaimed back in 1990: "How can you write 250 pages on the knapsack problem?" Indeed, the definition of the knapsack problem is easily understood even by a non-expert who will not suspect the presence of challenging research topics in this area at the first glance. However, in the last decade a large number of research publications contributed new results for the knapsack problem in all areas of interest such as exact algorithms, heuristics and approximation schemes. Moreover, the extension of the knapsack problem to higher dimensions both in the number of constraints and in the num ber of knapsacks, as well as the modification of the problem structure concerning the available item set and the objective function, leads to a number of interesting variations of practical relevance which were the subject of intensive research during the last few years. Hence, two years ago ...
Baronti, Marco; van der Putten, Robertus; Venturi, Irene
2016-01-01
This book, intended as a practical working guide for students in Engineering, Mathematics, Physics, or any other field where rigorous calculus is needed, includes 450 exercises. Each chapter starts with a summary of the main definitions and results, which is followed by a selection of solved exercises accompanied by brief, illustrative comments. A selection of problems with indicated solutions rounds out each chapter. A final chapter explores problems that are not designed with a single issue in mind but instead call for the combination of a variety of techniques, rounding out the book’s coverage. Though the book’s primary focus is on functions of one real variable, basic ordinary differential equations (separation of variables, linear first order and constant coefficients ODEs) are also discussed. The material is taken from actual written tests that have been delivered at the Engineering School of the University of Genoa. Literally thousands of students have worked on these problems, ensuring their real-...
... Home › Aging & Health A to Z › Thyroid Problems Font size A A A Print Share Glossary Basic ... enough thyroid hormone, usually of the thyroxine (T4) type of hormone. Your T4 levels can drop temporarily ...
... fully trust your sense of balance. Loss of balance also raises the risk of falls. This is a serious and even life-threatening ... 65. Balance disorders are serious because of the risk of falls. But occasionally balance problems may warn of another health condition, such ...
International Nuclear Information System (INIS)
Hoefling, O.
1980-01-01
The physical and technical fundamentals of energy conversion are described in popular form. There are chapters on fossil nuclear, and renewable energy sources. The final chapter attempts to give a picture of the complex interactions in the fields of energy economy and energy policy. (UA) [de
International Nuclear Information System (INIS)
Gong, E.Y.; Alexander, E.E.; McMaster, W.H.; Quinones, D.F.
1979-01-01
This report provides prospective users of the Lawrence Livermore Laboratory (LLL) fluid-structure interaction computer code, PELE-IC, a variety of test problems for verifying the code on CDC 7600 computer systems at facilities external to the LLL environment. The test problems have been successfully run on CDC 7600 computers at the LLL and Lawrence Berkeley Laboratory (LBL) computer centers
DEFF Research Database (Denmark)
Buur, Jacob; Gudiksen, Sune Klok
2012-01-01
Interaction design expands into new fields. Interaction design and business model innovation is a promising meeting of disciplines: Many businesses see the need to rethink their ways of doing business, and, as business models pose highly dynamic and interactive problems, interaction design has much...... with hypotheses and experiment with scenarios as a way of innovating their business models, and why this is so...... to offer. This paper compares 'tangible business models' in the form of pinball-like contraptions, designed by interaction design students with those developed by groups of professionals around concrete business issues. We will show how the interactive models encourage business people to play...
International Nuclear Information System (INIS)
Anon.
1982-01-01
The Interaction Region Group addressed the basic questions of how to collide the SLC beams, how to maximize and monitor the luminosity, and how to minimize the detector backgrounds at the interaction region. In practice, five subgroups evolved to study these questions. The final focus group provided three alternative designs to acheive the 1 to 2 micron beam spot size required by the SLC, as well as studying other problems including: eta, eta' matching from the collider arcs, the implementation of soft bends near the interaction region, beam emittance growth, and magnet tolerances in the final focus. The beam position monitor group proposed two devices, a strip line monitor, and a beamstrahlung monitor, to bring the beams into collision. The luminosity monitor group reviewed the possible QED processes that would be insensitive to weak interaction (Z 0 ) effects. The beam dumping group proposed locations for kicker and septum magnets in the final focus that would achieve a high dumping efficiency and would meet the desired beam tolerances at the Moller scattering target in the beam dump line. Working with the Polarization Group, the Moller experiment was designed into the beam dump beam line. A beam dump was proposed that would maintain radiation backgrounds (penetrating muons) at acceptible levels. The detector backgrounds group proposed soft-bend and masking configurations to shield the detector from synchrotron radiation from the hard/soft bends and from the final focus quadrupoles and evaluated the effectiveness of these designs for the three final focus optics designs. Backgrounds were also estimated from: large angle synchrotron radiation, local and distant beam-gas interactions, 2-photon interactions, and from neutrons and backscattered photons from the beamstrahlung dump
Isac, George
1992-01-01
The study of complementarity problems is now an interesting mathematical subject with many applications in optimization, game theory, stochastic optimal control, engineering, economics etc. This subject has deep relations with important domains of fundamental mathematics such as fixed point theory, ordered spaces, nonlinear analysis, topological degree, the study of variational inequalities and also with mathematical modeling and numerical analysis. Researchers and graduate students interested in mathematical modeling or nonlinear analysis will find here interesting and fascinating results.
International Nuclear Information System (INIS)
Bickerton, George E.
1997-01-01
Although there were not reasons to deplore against major activity release from any of the 110 industrial reactors authorized to operate in US, the nuclear incident that occurred at the Three Mile Island Plant in 1979 urged the public conscience toward the necessity of readiness to cope with events of this type. The personnel of the Emergency Planning Office functioning in the frame of US Department of Agriculture has already participated in around 600 intervention drillings on a federal, local or state scale to plan, test or asses radiological emergency plans or to intervene locally. These exercises allowed acquiring a significant experience in elaborating emergency plans, planning the drillings, working out scenarios and evaluation of the potential impact of accidents from the agricultural point of view. We have also taken part in different international drillings among which the most recent are INEX 1 and RADEX 94. We have found on these occasions that the agricultural problems are essential preoccupations in most of the cases no matter if the context is international, national, local or of state level. The paper poses problems specifically related to milk, fruits and vegetables, soils, meat and meat products. Finally the paper discusses issues like drilling planning, alarm and notification, sampling strategy, access authorizations for farmers, removing of contamination wastes. A number of social, political and economical relating problems are also mentioned
International Nuclear Information System (INIS)
Lukash, V.N.
1983-01-01
Information discussed at the 18th General Assembly of the International Astronomical Union and Symposium on ''Early Universe Evolution and Its Modern Structure'' on the problems of relic radiation, Hubble expansion, spatial structure and physics of the early Universe is presented. The spectrum of relic radioemission differs but slightly from the equilibrium one in the maximum range. In G. Smith (USA) opinion such difference may be caused by any radiosources radiating in the same wave range. The absence of unanimous opinion of astronomers on Hubble constant value is pointed out. G.Tam-man (Switzerland) estimates the Hubble constant 50+-7 km/s. J. Voculer (USA) gives a twice greater value. Such divergence is ca sed by various methods of determining distances up to remote galaxies and galaxy clusters. Many reports deal with large-scale Universe structure. For the first time considered are the processes which occurred in the epoch at times about 10 -35 c from the beginning of the Universe expansion. Such possibility is presented by the theory of ''great unification'' which permits to explain some fundamental properties of the Universe: spatial uniformity of isotropic expansion, existence of small primary density perturbations
International Nuclear Information System (INIS)
Carruthers, R.
It is pointed out that plasma parameters for a fusion reactor have been fairly accurately defined for many years, and the real plasma physics objective must be to find the means of achieving and maintaining these specifiable parameters. There is good understanding of the generic technological problems: breading blankets and shields, radiation damage, heat transfer and methods of magnet design. The required plasma parameters for fusion self-heated reactors are established at ntausub(E) approximately 2.10 14 cm -3 sec, plasma radius 1.5 to 3 m, wall loading 5 to 10 MW cm -2 , temperature 15 keV. Within this model plasma control by quasi-steady burn as a key problem is studied. It is emphasized that the future programme must interact more closely with engineering studies and should concentrate upon research which is relevant to reactor plasmas. (V.P.)
DEFF Research Database (Denmark)
Tietjen, Anne; Jørgensen, Gertrud
2016-01-01
, place-based and project-oriented process directed at concrete physical outcomes. We frame strategic planning as a translation process where the interaction between human and non-human actors translates a unique, complex and contested situation into an innovated situation. We find that local physical...... on the case of a Danish planning process which was carried out in collaboration with a charitable trust, this paper discusses an emerging strategic planning approach at the municipal level. We use the concept of wicked problems, strategic planning theory and Actor-Network-Theory to study a collaborative...... projects played a major role in this process. First, they acted as a vehicle that assembled planners, politicians and stakeholders to work towards strategic visions across multiple scales. Second and consequently, they stimulated considerable second and third order effects in the form of shared problem...
International Nuclear Information System (INIS)
Emery, V.J.; Kivelson, S.A.
1993-01-01
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
Energy Technology Data Exchange (ETDEWEB)
Emery, V.J. [Brookhaven National Lab., Upton, NY (United States); Kivelson, S.A. [California Univ., Los Angeles, CA (United States). Dept. of Physics
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.
International Nuclear Information System (INIS)
Seiler, E.
1985-01-01
Confinement of quarks is sometimes taken as some kind of dogma in the contemporary theory of strong interactions - quantum chromo-dynamics (QCD). Scientists should not be content with that. What is meant by ''permanent confinement'' should be formulated more precisely to see whether the theory has this property or not. The author looks at some possible interpretations of ''confinement'' and their shortcomings and then turns to the most widely used rather pragmatic definition based on the somewhat unphysical notion of infinitely heavy external sources. He describes what is known about the problem and tries to bring into focus some aspects that are insufficiently understood in his opinion
International Nuclear Information System (INIS)
Bosanac, Slobodan Danko
2016-01-01
This book is devoted to theoretical methods used in the extreme circumstances of very strong electromagnetic fields. The development of high power lasers, ultrafast processes, manipulation of electromagnetic fields and the use of very fast charged particles interacting with other charges requires an adequate theoretical description. Because of the very strong electromagnetic field, traditional theoretical approaches, which have primarily a perturbative character, have to be replaced by descriptions going beyond them. In the book an extension of the semi-classical radiation theory and classical dynamics for particles is performed to analyze single charged atoms and dipoles submitted to electromagnetic pulses. Special attention is given to the important problem of field reaction and controlling dynamics of charges by an electromagnetic field.
Experimental Aspects of Nuclear Interaction
Energy Technology Data Exchange (ETDEWEB)
Slaus, I. [Institute ' ' Rudjer Boskovic' ' , Zagreb, Yugoslavia (Croatia)
1970-07-15
1. Introduction; 2. Basic features of nuclear interaction; 3. How accurate is our present knowledge of phase parameters? 4. Experimental problems in N-N scattering studies; 5. N-N potential models; 6. Some open problems in nuclear interaction studies. (author)
Conjugate problems in convective heat transfer
Dorfman, Abram S
2009-01-01
The conjugate heat transfer (CHT) problem takes into account the thermal interaction between a body and fluid flowing over or through it, a key consideration in both mechanical and aerospace engineering. Presenting more than 100 solutions of non-isothermal and CHT problems, this title considers the approximate solutions of CHT problems.
Problems in nonlinear resistive MHD
International Nuclear Information System (INIS)
Turnbull, A.D.; Strait, E.J.; La Haye, R.J.; Chu, M.S.; Miller, R.L.
1998-01-01
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
Turk, Matthew
2013-01-01
In its early years, the field of computer vision was largely motivated by researchers seeking computational models of biological vision and solutions to practical problems in manufacturing, defense, and medicine. For the past two decades or so, there has been an increasing interest in computer vision as an input modality in the context of human-computer interaction. Such vision-based interaction can endow interactive systems with visual capabilities similar to those important to human-human interaction, in order to perceive non-verbal cues and incorporate this information in applications such
Two interacting Hofstadter butterflies
International Nuclear Information System (INIS)
Barelli, A.; Bellissard, J.; Jacquod, P.
1997-01-01
The problem of two interacting particles in a quasiperiodic potential is addressed. Using analytical and numerical methods, we explore the spectral properties and eigenstates structure from the weak to the strong interaction case. More precisely, a semiclassical approach based on noncommutative geometry techniques is used to understand the intricate structure of such a spectrum. An interaction induced localization effect is furthermore emphasized. We discuss the application of our results on a two-dimensional model of two particles in a uniform magnetic field with on-site interaction. copyright 1997 The American Physical Society
International Nuclear Information System (INIS)
Musielak, Z E; Quarles, B
2014-01-01
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. (review article)
DEFF Research Database (Denmark)
Vidal, Rene Victor Valqui
1994-01-01
The paper studies the problem of determining the number and dimensions of sizes of apparel so as to maximize profits. It develops a simple one-variable bisection search algorithm that gives the optimal solution. An example is solved interactively using a Macintosh LC and Math CAD, a mathematical...
Aero-Acoustic-Structural Optimization Analysis and Testing, Phase I
National Aeronautics and Space Administration — This proposal effort is concerned with the development of a novel multidisciplinary optimization scheme and computer software for the effective design of advanced...
Collision and interaction phenomena - a historical outline
International Nuclear Information System (INIS)
Radmaneche, R.
1977-09-01
Collisions and interactions have become important for the description of matter. The author presents an outline which deals with elastic and inelastic collisions, with strong interactions, electromagnetic interactions, weak interactions and gravitational interactions. It is shown that the description of such processes has developed parallel with the understanding of matter and with the mechanism of the phenomena. Current and unsolved problems are mentioned
International Nuclear Information System (INIS)
Saperstein, E.E.
1992-01-01
The influence of the detailed behavior of the nuclear densities on the Glauber-theory description of hadron-nucleus scattering is discussed in connection with the problem of determination of elementary hadron-nucleon amplitudes from such analysis. Arguments are given in favor of using the self-consistent FFS nuclear densities for this purpose. 20 refs., 6 figs
Wang, Shu-Ming; Hou, Huei-Tse; Wu, Sheng-Yi
2017-01-01
Instructional strategies can be helpful in facilitating students' knowledge construction and developing advanced cognitive skills. In the context of collaborative learning, instructional strategies as scripts can guide learners to engage in more meaningful interaction. Previous studies have been investigated the benefits of different instructional…
Is Disability a Health Problem?
Directory of Open Access Journals (Sweden)
Malcolm MacLachlan
2013-12-01
Full Text Available We welcome Andrew Haig's critique of our paper, "Disability & Health: A research agenda" in Social Inclusion. Our paper sought to identify research priorities to better understand, provide enhanced services and a better quality of life for people with disabilities, particularly in relation to their health and wellbeing. Haig's critique makes several important points that deserve serious consideration. His comments reflect a view of the relationship between disability and health which is different from the one we have espoused. Specifically, Haig argues that (a disability is a health problem, (b medical rehabilitation should be separated from Community Based Rehabilitation (CBR, and (c the evidence base for medical rehabilitation is much stronger than for CBR. We address each of these points below arguing that while some types of disability clearly result from health problems; often disability is not experienced as a health problem; and sometimes, disability in interaction with restricted access is the cause of health problems.
Problem-Solving during Shared Reading at Kindergarten
Gosen, Myrte N.; Berenst, Jan; de Glopper, Kees
2015-01-01
This paper reports on a conversation analytic study of problem-solving interactions during shared reading at three kindergartens in the Netherlands. It illustrates how teachers and pupils discuss book characters' problems that arise in the events in the picture books. A close analysis of the data demonstrates that problem-solving interactions do…
The problem of symmetry breaking hierarchy
International Nuclear Information System (INIS)
Natale, A.A.
1983-01-01
The problem of symmetry breaking hierarchy in grand unified theories is discussed, proving the impossibility to get a big hierarchy of interactions, in a natural way within the framework of perturbation theory. (L.C.) [pt
Luciani , Annie
2007-01-01
International audience; The expression instrumental interaction as been introduced by Claude Cadoz to identify a human-object interaction during which a human manipulates a physical object - an instrument - in order to perform a manual task. Classical examples of instrumental interaction are all the professional manual tasks: playing violin, cutting fabrics by hand, moulding a paste, etc.... Instrumental interaction differs from other types of interaction (called symbolic or iconic interactio...
Energy Technology Data Exchange (ETDEWEB)
Abdou, M.A.; Boyd, R.D.; Easor, J.R.; Gauster, W.B.; Gordon, J.D.; Mattas, R.F.; Morgan, G.D.; Ulrickson, M.A,; Watson, R.D.; Wolfer, W.G,
1984-06-01
A technical assessment of the critical issues and problem areas for high heat flux materials and components (HHFMC) in magnetic fusion devices shows these problems to be of critical importance for the successful operation of near-term fusion experiments and for the feasibility and attractiveness of long-term fusion reactors. A number of subgroups were formed to assess the critical HHFMC issues along the following major lines: (1) source conditions, (2) systems integration, (3) materials and processes, (4) thermal hydraulics, (5) thermomechanical response, (6) electromagnetic response, (7) instrumentation and control, and (8) test facilities. The details of the technical assessment are presented in eight chapters. The primary technical issues and needs for each area are highlighted.
International Nuclear Information System (INIS)
Abdou, M.A.; Boyd, R.D.; Easor, J.R.
1984-06-01
A technical assessment of the critical issues and problem areas for high heat flux materials and components (HHFMC) in magnetic fusion devices shows these problems to be of critical importance for the successful operation of near-term fusion experiments and for the feasibility and attractiveness of long-term fusion reactors. A number of subgroups were formed to assess the critical HHFMC issues along the following major lines: (1) source conditions, (2) systems integration, (3) materials and processes, (4) thermal hydraulics, (5) thermomechanical response, (6) electromagnetic response, (7) instrumentation and control, and (8) test facilities. The details of the technical assessment are presented in eight chapters. The primary technical issues and needs for each area are highlighted
Computational problems in Arctic Research
International Nuclear Information System (INIS)
Petrov, I
2016-01-01
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. (paper)
Class and Home Problems: Optimization Problems
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…
Interactive Foresight Simulation
DEFF Research Database (Denmark)
Hansen, Mette Sanne; Rasmussen, Lauge Baungaard; Jacobsen, Peter
2016-01-01
The Combined Simulation Approach (CSA) is a way to evaluate risks and address potential unforeseen problems in a more interactive way than what is often observed in practice in companies or sectors. The approach is based on a combination of scenario analysis and discrete-event computer simulation...
Exactly soluble problems in statistical mechanics
International Nuclear Information System (INIS)
Yang, C.N.
1983-01-01
In the last few years, a number of two-dimensional classical and one-dimensional quantum mechanical problems in statistical mechanics have been exactly solved. Although these problems range over models of diverse physical interest, their solutions were obtained using very similar mathematical methods. In these lectures, the main points of the methods are discussed. In this introductory lecture, an overall survey of all these problems without going into the detailed method of solution is given. In later lectures, they shall concentrate on one particular problem: the delta function interaction in one dimension, and go into the details of that problem
Approaching messy problems: strategies for environmental analysis
L. M. Reid; R. R. Ziemer; T. E. Lisle
1996-01-01
Environmental problems are never neatly defined. Instead, each is a tangle of interacting processes whose manifestation and interpretation are warped by the vagaries of time, weather, expectation, and economics. Each problem involves livelihoods, values, and numerous specialized disciplines. Nevertheless, federal agencies in the Pacific Northwest have been given the...
Problem Solving Reasoning and Problem Based Instruction in Geometry Learning
Sulistyowati, F.; Budiyono, B.; Slamet, I.
2017-09-01
This research aims to analyze the comparison Problem Solving Reasoning (PSR) and Problem Based Instruction (PBI) on problem solving and mathematical communication abilities viewed from Self-Regulated Learning (SRL). Learning was given to grade 8th junior high school students. This research uses quasi experimental method, and then with descriptive analysis. Data were analyzed using two-ways multivariate analysis of variance (MANOVA) and one-way analysis of variance (ANOVA) with different cells. The result of data analysis were learning model gives different effect, level of SRL gives the same effect, and there is no interaction between the learning model with the SRL on the problem solving and mathematical communication abilities. The t-test statistic was used to find out more effective learning model. Based on the test, regardless of the level of SRL, PSR is more effective than PBI for problemsolving ability. The result of descriptive analysis was PSR had the advantage in creating learning that optimizing the ability of learners in reasoning to solve a mathematical problem. Consequently, the PSR is the right learning model to be applied in the classroom to improve problem solving ability of learners.
International Nuclear Information System (INIS)
Chanda, R.
1981-01-01
The theoretical and experimental evidences to form a basis for Lagrangian Quantum field theory for Weak Interactions are discussed. In this context, gauge invariance aspects of such interactions are showed. (L.C.) [pt
Inverse problem in nuclear physics
International Nuclear Information System (INIS)
Zakhariev, B.N.
1976-01-01
The method of reconstruction of interaction from the scattering data is formulated in the frame of the R-matrix theory in which the potential is determined by position of resonance Esub(lambda) and their reduced widths γ 2 lambda. In finite difference approximation for the Schroedinger equation this new approach allows to make the logics of the inverse problem IP more clear. A possibility of applications of IP formalism to various nuclear systems is discussed. (author)
International Nuclear Information System (INIS)
Kaplan, I.G.; Rodimova, O.B.; AN SSSR, Tomsk. Inst. Optiki Atmosfery)
1978-01-01
The present state of the intermolecular interaction theory is described. The general physical picture of the molecular interactions is given, the relative contributions of interactions of different types are analyzed (electrostatic, resonance, induction, dispersion, relativistic, magnetostatic and exchange), and the main ones in each range of separations are picked out. The methods of the potential curve calculations are considered, specific for definite separations between the interacting systems. The special attention is paid to the analysis of approximations used in different theoretical calculation methods
... Problems Diabetes, Sexual, & Bladder Problems Clinical Trials Preventing Diabetes Problems View or Print All Sections Heart Disease & ... to help control symptoms and restore intimacy. Depression & Diabetes Depression is common among people with a chronic, ...
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)
Problems in differential equations
Brenner, J L
2013-01-01
More than 900 problems and answers explore applications of differential equations to vibrations, electrical engineering, mechanics, and physics. Problem types include both routine and nonroutine, and stars indicate advanced problems. 1963 edition.
Foreign language interactive didactics
Directory of Open Access Journals (Sweden)
Arnaldo Moisés Gómez
2016-06-01
Full Text Available Foreign Language Interactive Didactics is intended for foreign language teachers and would-be teachers since it is an interpretation of the foreign language teaching-learning process is conceived from a reflexive social interaction. This interpretation declares learning based on interactive tasks that provide learners with opportunities to interact meaningfully among them, as a way to develop interactional competence as objective in itself and as a means to obtain communicative competence. Foreign language interactive didactics claims for the unity of reflection and action while learning the language system and using it to communicate, by means of solving problems presented in interactive tasks. It proposes a kind of teaching that is interactive, developmental, collaborative, holist, cognitive, problematizing, reflexive, student centered, humanist, and with a strong affective component that empower the influencing psychological factors in learning. This conception appears in the book: DIDÁCTICA INTERACTIVA DE LENGUAS (2007 y 2010. The book is used as a textbook for the subject of Didactics that is part of the curriculum in language teachers’ formation of all the pedagogical sciences universities, in Spanish teachers’ formation who are not Spanish speaking people at Havana University, and also as a reference book for postgraduate courses, master’s and doctorate’ s degrees.
Hamilton, Mark F.
1990-12-01
This report discusses five projects all of which involve basic theoretical research in nonlinear acoustics: (1) pulsed finite amplitude sound beams are studied with a recently developed time domain computer algorithm that solves the KZK nonlinear parabolic wave equation; (2) nonlinear acoustic wave propagation in a liquid layer is a study of harmonic generation and acoustic soliton information in a liquid between a rigid and a free surface; (3) nonlinear effects in asymmetric cylindrical sound beams is a study of source asymmetries and scattering of sound by sound at high intensity; (4) effects of absorption on the interaction of sound beams is a completed study of the role of absorption in second harmonic generation and scattering of sound by sound; and (5) parametric receiving arrays is a completed study of parametric reception in a reverberant environment.
Mathematical problems in meteorological modelling
Csomós, Petra; Faragó, István; Horányi, András; Szépszó, Gabriella
2016-01-01
This book deals with mathematical problems arising in the context of meteorological modelling. It gathers and presents some of the most interesting and important issues from the interaction of mathematics and meteorology. It is unique in that it features contributions on topics like data assimilation, ensemble prediction, numerical methods, and transport modelling, from both mathematical and meteorological perspectives. The derivation and solution of all kinds of numerical prediction models require the application of results from various mathematical fields. The present volume is divided into three parts, moving from mathematical and numerical problems through air quality modelling, to advanced applications in data assimilation and probabilistic forecasting. The book arose from the workshop “Mathematical Problems in Meteorological Modelling” held in Budapest in May 2014 and organized by the ECMI Special Interest Group on Numerical Weather Prediction. Its main objective is to highlight the beauty of the de...
International Nuclear Information System (INIS)
Elliott, J.P.
1981-01-01
This chapter attempts to describe and compare some of the more important nucleon-nucleon interactions that have been used in nuclear structure calculations, and to relate them where possible to the real nucleon-nucleon interaction. Explains that different interactions have been used depending on whether one is fitting to total binding energies and densities with a Hartree Fock (HF) calculation or fitting to spectra and spectroscopic data in a shell model calculation. Examines both types of calculation after two preliminary sections concerned with notation and with the philosophy underlying the use of model spaces and effective interactions. Discusses Skyrme interactions, finite range interactions, small model space, large model space, and the Sussex potential matrix elements. Focuses on the more empirical approaches in which a simple form is chosen for the effective interaction in a given model space and the parameters are deduced from fitting many-body data
To theory of gravitational interaction
Minkevich, A. V.
2008-01-01
Some principal problems of general relativity theory and attempts of their solution are discussed. The Poincare gauge theory of gravity as natural generalization of Einsteinian gravitation theory is considered. The changes of gravitational interaction in the frame of this theory leading to the solution of principal problems of general relativity theory are analyzed.
Narrative Cognition in Interactive Systems
DEFF Research Database (Denmark)
Bruni, Luis Emilio; Baceviciute, Sarune; Arief, Mohammed
2014-01-01
In this article we explore some of the methodological problems related to characterizing cognitive aspects of involvement with interactive narratives using well known EEG/ERP techniques. To exemplify this, we construct an experimental EEG-ERP set-up with an interactive narrative that considers th...
Cheryl A. Smith
2008-01-01
Diagnosing Christmas tree problems can be a challenge, requiring a basic knowledge of plant culture and physiology, the effect of environmental influences on plant health, and the ability to identify the possible causes of plant problems. Developing a solution or remedy to the problem depends on a proper diagnosis, a process that requires recognition of a problem and...
Potentials of the inverse scattering problem in the three-nucleon problem
International Nuclear Information System (INIS)
Pushkash, A.M.; Simenog, I.V.; Shapoval, D.V.
1993-01-01
Possibilities of using the method of the inverse scattering problem for describing simultaneously the two-nucleon and the low-energy three-nucleon data in the S-interaction approximation are examined. 20 refs., 3 figs., 1 tab
Islamic Education Research Problem
Directory of Open Access Journals (Sweden)
Abdul Muthalib
2012-04-01
Full Text Available This paper will discuss Islamic educational studies that is reviewing how to find, limit and define problems and problem-solving concepts. The central question of this paper is to describe how to solve the problem in Islamic educational research. A researcher or educator who has the knowledge, expertise, or special interest on education for example is usually having a sensitivity to issues relating to educational research. In the research dimension of religious education, there are three types of problems, namely: Problems foundation, structural problems and operational issues. In doing research in Islamic education someone should understand research problem, limiting and formulating the problem, how to solve the problem, other problem relating to the point of research, and research approach.
DEFF Research Database (Denmark)
Petersen, Marianne Graves; Krogh, Peter; Ludvigsen, Martin
2005-01-01
Within architecture, there is a long tradition of careful design of floors. The design has been concerned with both decorating floors and designing floors to carry information. Ubiquitous computing technology offers new opportunities for designing interactive floors. This paper presents three...... different interactive floor concepts. Through an urban perspective it draws upon the experiences of floors in architecture, and provides a set of design issues for designing interactive floors....
DEFF Research Database (Denmark)
2003-01-01
The video Playful Interaction describes a future architectural office, and envisions ideas and concepts for playful interactions between people, materials and appliances in a pervasive and augmented working environment. The video both describes existing developments, technologies and designs...... as well as ideas not yet implemented such as playful modes of interaction with an augmented ball. Playful Interaction has been used as a hybrid of a vision video and a video prototype (1). Externally the video has been used to visualising our new ideas, and internally the video has also worked to inspire...
Sahade, Jorge; Ter Haar, D
1978-01-01
Interacting Binary Stars deals with the development, ideas, and problems in the study of interacting binary stars. The book consolidates the information that is scattered over many publications and papers and gives an account of important discoveries with relevant historical background. Chapters are devoted to the presentation and discussion of the different facets of the field, such as historical account of the development in the field of study of binary stars; the Roche equipotential surfaces; methods and techniques in space astronomy; and enumeration of binary star systems that are studied
IDEAL Problem Solving dalam Pembelajaran Matematika
Directory of Open Access Journals (Sweden)
Eny Susiana
2012-01-01
Full Text Available Most educators agree that problem solving is among the most meaningful and importantkinds of learning and thingking. That is, the central focus of learning and instructionshould be learning to solve problems. There are several warrants supporting that claims.They are authenticity, relevance, problem solving engages deeper learning angtherefore enhances meaning making, and constructed to represent problems (problemsolving is more meaningful. It is the reason why we must provide teaching and learningto make studentâ€™s problem solving skill in progress. There are many informationprocessingmodels of problem solving, such as simplified model of the problem-solvingprocess by Gicks, Polyaâ€™s problem solving process etc. One of them is IDEAL problemsolving. Each letter of IDEAL is stand for an aspect of thinking that is important forproblem solving. IDEAL is identify problem, Define Goal, Explore possible strategies,Anticipate outcme and Act, and Look back and learn. Using peer interaction andquestion prompt in small group in IDEAL problem solving teaching and Learning canimprove problem solving skill.Kata kunci: IDEAL Problem Solving, Interaksi Sebaya, Pertanyaan Penuntun, KelompokKecil.
Tse, Wai S; Siu, Angela F Y; Wong, Tracy K Y
2017-12-01
This study aims to explore the interrelationship among maternal oxytocin (OT) responsiveness, maternal mental health, maternal parenting behavior, and mental health of children under a free-play interaction. 61 mother-child dyads were recruited for the study. Maternal mental health problem and parenting self-efficacy were measured using self-reported questionnaires. The mental health problems of children were also evaluated using a mother-reported questionnaire. Furthermore, salivary OT was collected before and after a standardized 10min free-play interaction. Parenting behaviors, including eye gaze and touch, were measured during the free-play interaction. Maternal OT responsiveness was significantly associated with less maternal mental health problem, touch frequency, and mental health problem of children but not with parenting self-efficacy. In the multivariate linear regression analysis that considers maternal OT responsiveness and maternal and children's mental health problems, maternal OT responsiveness was not associated with the mental health problems of children. This result suggested that maternal mental health problem played a mediational role between maternal OT responsiveness and the mental health problem of children. Results supported the assertion that maternal OT responsiveness contributed to the increased risk of maternal mental health problems and, subsequently, the risk of mental health problems of their children. Copyright © 2017 Elsevier B.V. All rights reserved.
DEFF Research Database (Denmark)
Petersen, Marianne Graves; Iversen, Ole Sejer; Krogh, Peter
2004-01-01
, as it promotes aesthetics of use, rather than aesthetics of appearance. We coin this approach in the perspective of aesthetic interaction. Finally we make the point that aesthetics is not re-defining everything known about interactive systems. We provide a framework placing this perspective among other...
DEFF Research Database (Denmark)
Lawson, Lartey; Nielsen, Kurt
2005-01-01
We discuss individual learning by interactive benchmarking using stochastic frontier models. The interactions allow the user to tailor the performance evaluation to preferences and explore alternative improvement strategies by selecting and searching the different frontiers using directional...... in the suggested benchmarking tool. The study investigates how different characteristics on dairy farms influences the technical efficiency....
DEFF Research Database (Denmark)
Löwgren, Jonas; Eriksen, Mette Agger; Linde, Per
2006-01-01
We report an ongoing study of palpable computing to support surgical rehabilitation, in the general field of interaction design for ubiquitous computing. Through explorative design, fieldwork and participatory design techniques, we explore the design principle of explicit interaction as an interp...
The Markov moment problem and extremal problems
Kreĭn, M G; Louvish, D
1977-01-01
In this book, an extensive circle of questions originating in the classical work of P. L. Chebyshev and A. A. Markov is considered from the more modern point of view. It is shown how results and methods of the generalized moment problem are interlaced with various questions of the geometry of convex bodies, algebra, and function theory. From this standpoint, the structure of convex and conical hulls of curves is studied in detail and isoperimetric inequalities for convex hulls are established; a theory of orthogonal and quasiorthogonal polynomials is constructed; problems on limiting values of integrals and on least deviating functions (in various metrics) are generalized and solved; problems in approximation theory and interpolation and extrapolation in various function classes (analytic, absolutely monotone, almost periodic, etc.) are solved, as well as certain problems in optimal control of linear objects.
DEFF Research Database (Denmark)
Fogtmann, Maiken Hillerup; Fritsch, Jonas; Kortbek, Karen Johanne
2008-01-01
Within the Human-Computer Interaction community there is a growing interest in designing for the whole body in interaction design. The attempts aimed at addressing the body have very different outcomes spanning from theoretical arguments for understanding the body in the design process, to more...... practical examples of designing for bodily potential. This paper presents Kinesthetic Interaction as a unifying concept for describing the body in motion as a foundation for designing interactive systems. Based on the theoretical foundation for Kinesthetic Interaction, a conceptual framework is introduced...... to reveal bodily potential in relation to three design themes – kinesthetic development, kinesthetic means and kinesthetic disorder; and seven design parameters – engagement, sociality, movability, explicit motivation, implicit motivation, expressive meaning and kinesthetic empathy. The framework is a tool...
Handbook of mathematical techniques for wavestructure interactions
Linton, CM
2001-01-01
INTRODUCTIONThe Water-Wave ProblemThe Linearised EquationsInteraction of a Wave with a StructureReciprocity RelationsEnergy of the Fluid MotionEIGENFUNCTION EXPANSIONSIntroductionConstruction of Vertical EigenfunctionTwo-Dimensional ProblemsThree-Dimensional ProblemsMatched Eigenfunction ExpansionsMULTIPOLE EXPANSIONSIntroductionIsolated ObstaclesMultiple BodiesINTEGRAL EQUATIONSSource DistributionGreen's TheoremThin ObstaclesInterior ProblemsFree-Surface ProblemsNumerical Evaluation of Green's functions
Differential equations problem solver
Arterburn, David R
2012-01-01
REA's Problem Solvers is a series of useful, practical, and informative study guides. Each title in the series is complete step-by-step solution guide. The Differential Equations Problem Solver enables students to solve difficult problems by showing them step-by-step solutions to Differential Equations problems. The Problem Solvers cover material ranging from the elementary to the advanced and make excellent review books and textbook companions. They're perfect for undergraduate and graduate studies.The Differential Equations Problem Solver is the perfect resource for any class, any exam, and
Interactive tabletops in education
Dillenbourg, Pierre; Evans, Michael
2011-01-01
Interactive tabletops are gaining increased attention from CSCL researchers. This paper analyses the relation between this technology and teaching and learning processes. At a global level, one could argue that tabletops convey a socio-constructivist flavor: they support small teams that solve problems by exploring multiple solutions. The development of tabletop applications also witnesses the growing importance of face-to-face collaboration in CSCL and acknowledges the physicality of learnin...
The Students Decision Making in Solving Discount Problem
Abdillah; Nusantara, Toto; Subanji; Susanto, Hery; Abadyo
2016-01-01
This research is reviewing students' process of decision making intuitively, analytically, and interactively. The research done by using discount problem which specially created to explore student's intuition, analytically, and interactively. In solving discount problems, researcher exploring student's decision in determining their attitude which…
Energy Technology Data Exchange (ETDEWEB)
NONE
1999-03-01
Global environmental problems are growing quite serious in developing countries, yet they are requested to properly deal with them without making light of sustainable development, for which international cooperation and diffusion of technologies for the development of environmental technologies are mandatory. Japan, utilizing what it learned from pollution within in the past and making the best use of its technologies and knowledge for environmental improvement in developing countries in Asia, has been hosting since fiscal 1997 a function of Environmental Technology Research Network in the Asia-Pacific Region function. In fiscal 1998, a fifth international symposium was convened at Science City Center at the foot of Mt. Suzuka on November 26 and 27. The central theme was the development of environmental technologies and international cooperation for developing nations, and the event attracted 180 participants from inside Japan and abroad. A number of concrete themes came out of working groups on water quality, air quality, and energy/waste, which concerned the drafting of propositions for international collaborative researches. As for researches abroad, four typical Malaysian institutes were visited. (NEDO)
Sleep problems are a common side effect during cancer treatment. Learn how a polysomnogram can assess sleep problems. Learn about the benefits of managing sleep disorders in men and women with cancer.
The internal percolation problem
International Nuclear Information System (INIS)
Bezsudnov, I.V.; Snarskii, A.A.
2010-01-01
The internal percolation problem (IP) as a new type of the percolation problem is introduced and investigated. In spite of the usual (or external) percolation problem (EP) when the percolation current flows from the top to the bottom of the system, in IP case the voltage is applied through bars which are present in the hole located within the system. The EP problem has two major parameters: M-size of the system and a 0 -size of inclusions, bond size, etc. The IP problem holds one parameter more: size of the hole L. Numerical simulation shows that the critical indexes of conductance for the IP problem are very close to those in the EP problem. On the contrary, the indexes of the relative spectral noise density of 1/f noise and higher moments differ from those in the EP problem. The basics of these facts is discussed.
Challenging problems in algebra
Posamentier, Alfred S
1996-01-01
Over 300 unusual problems, ranging from easy to difficult, involving equations and inequalities, Diophantine equations, number theory, quadratic equations, logarithms, more. Detailed solutions, as well as brief answers, for all problems are provided.
Choate, Joyce S.
1990-01-01
The initial step of a strategic process for solving mathematical problems, "studying the question," is discussed. A lesson plan for teaching students to identify and revise arithmetic problems is presented, involving directed instruction and supervised practice. (JDD)
Separable expansion for realistic multichannel scattering problems
International Nuclear Information System (INIS)
Canton, L.; Cattapan, G.; Pisent, G.
1987-01-01
A new approach to the multichannel scattering problem with realistic local or nonlocal interactions is developed. By employing the negative-energy solutions of uncoupled Sturmian eigenvalue problems referring to simple auxiliary potentials, the coupling interactions appearing to the original multichannel problem are approximated by finite-rank potentials. By resorting to integral-equation tecniques the coupled-channel equations are then reduced to linear algebraic equations which can be straightforwardly solved. Compact algebraic expressions for the relevant scattering matrix elements are thus obtained. The convergence of the method is tasted in the single-channel case with realistic optical potentials. Excellent agreement is obtained with a few terms in the separable expansion for both real and absorptive interactions
Noble, Joshua
2012-01-01
Ready to create rich interactive experiences with your artwork, designs, or prototypes? This is the ideal place to start. With this hands-on guide, you'll explore several themes in interactive art and design-including 3D graphics, sound, physical interaction, computer vision, and geolocation-and learn the basic programming and electronics concepts you need to implement them. No previous experience is necessary. You'll get a complete introduction to three free tools created specifically for artists and designers: the Processing programming language, the Arduino microcontroller, and the openFr
International Nuclear Information System (INIS)
Arbuzov, B.A.
1977-01-01
Described are modern views on the particle structure and particle interactions at high energies. According to the latest data recieved, all particles can be classified in three groups: 1) strong interacting hadrons; 2) leptons, having no strong interactions; 3) photon. The particle structure is described in a quark model, and with the use of gluons. The elementary particle theory is based on the quantum field theory. The energy increase of interacting particles enables to check the main theory principles, such as conventions for causality, relativistic invariance and unitarity. Investigations of weak interactions are of great importance. The progress in this field is connected with unified gauge theories of weak and electromagnetic interactions. For weak interactions promissing are the experiments with colliding electron-proton rings. The new data, especially at higher energies, will lead to a further refinement of the nature of particles and their interactions
THE QUALITY OF MATHEMATICAL PROBLEMS - EVALUATION AND SELF-EVALUATION
Directory of Open Access Journals (Sweden)
Patáková, Eva
2013-09-01
Full Text Available The research presented in the article consists of two parts. Firstly, opinions on mathematical problem quality are explored within four groups of participants (novices, specialists and experts in problem posing; high school students who never posed their own problems. Secondly, self-reflections written by the participants who have some experience in problem posing (novices, specialists and experts are explored and compared with the general view of problem quality received in the first part of the research. The more experienced problem posers have more requirements on problem quality (both as general requirements and within their own work on posing problems. There is a slight decrease in ability to notice important features of mathematical problem quality after the first experience in problem posing. Experts lay stress on mathematical features of the problem whilst novices and specialists more on problem – student interaction.
International Nuclear Information System (INIS)
Weinberg, S.
1989-01-01
Cosmological constant problem is discussed. History of the problem is briefly considered. Five different approaches to solution of the problem are described: supersymmetry, supergravity, superstring; anthropic approach; mechamism of lagrangian alignment; modification of gravitation theory and quantum cosmology. It is noted that approach, based on quantum cosmology is the most promising one
Hayes, John R.
This book, designed for a college course on general problem-solving skills, focuses on skills that can be used by anyone in solving problems that occur in everyday life. Part I considers theory and practice: understanding problems, search, and protocol analysis. Part II discusses memory and knowledge acquisition: the structure of human memory,…
The rational complementarity problem
Heemels, W.P.M.H.; Schumacher, J.M.; Weiland, S.
1999-01-01
An extension of the linear complementarity problem (LCP) of mathematical programming is the so-called rational complementarity problem (RCP). This problem occurs if complementarity conditions are imposed on input and output variables of linear dynamical input/state/output systems. The resulting
The triangle scheduling problem
Dürr, Christoph; Hanzálek, Zdeněk; Konrad, Christian; Seddik, Yasmina; Sitters, R.A.; Vásquez, Óscar C.; Woeginger, Gerhard
2017-01-01
This paper introduces a novel scheduling problem, where jobs occupy a triangular shape on the time line. This problem is motivated by scheduling jobs with different criticality levels. A measure is introduced, namely the binary tree ratio. It is shown that the Greedy algorithm solves the problem to
Pollution problems plague Poland
International Nuclear Information System (INIS)
Bajsarowicz, J.F.
1989-01-01
Poland's environmental problems are said to stem from investments in heavy industries that require enormous quantities of power and from the exploitation of two key natural resources: coal and sulfur. Air and water pollution problems and related public health problems are discussed
Classifying IS Project Problems
DEFF Research Database (Denmark)
Munk-Madsen, Andreas
2006-01-01
The literature contains many lists of IS project problems, often in the form of risk factors. The problems sometimes appear unordered and overlapping, which reduces their usefulness to practitioners as well as theoreticians. This paper proposes a list of criteria for formulating project problems...
Inverse problems of geophysics
International Nuclear Information System (INIS)
Yanovskaya, T.B.
2003-07-01
This report gives an overview and the mathematical formulation of geophysical inverse problems. General principles of statistical estimation are explained. The maximum likelihood and least square fit methods, the Backus-Gilbert method and general approaches for solving inverse problems are discussed. General formulations of linearized inverse problems, singular value decomposition and properties of pseudo-inverse solutions are given
EFFECT OF PROBLEM BASED LEARNING AND MODEL CRITICAL THINKING ABILITY TO PROBLEM SOLVING SKILLS
Directory of Open Access Journals (Sweden)
Unita S. Zuliani Nasution
2016-12-01
Full Text Available The purposes of this research were to analyze the different between physic resolving problem ability by using problem based learning model and direct instruction model, the different of physic resolving problem ability between the students that have critical thinking ability upper the average and the students that have critical thinking ability under the average, and the interaction of problem based learning model toward critical thinking ability and students’ physic resolving problem ability. This research was quasy experimental research that use critical thinking ability tests and physic resolving problem ability tests as the instruments. Result of the research showed that the students’ physic resolving problem ability by using problem based learning model was better than by using direct instruction model, students’ physic resolving problem ability and critical thinking ability upper the average showed better different and result than students’ critical thinking ability under the average, besides there was an interaction between problem based learning model and critical thinking ability in improving students’ physic resolving problem ability.
Muon problem in UHECR investigations
International Nuclear Information System (INIS)
Petrukhin, A A; Bogdanov, A G; Kokoulin, R P
2013-01-01
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 X max measurements. Really, the excess of muons appears already at lower energies (10 16 − 10 17 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 10 18 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.
Energy Technology Data Exchange (ETDEWEB)
Dowrick, N.J. (Dept. of Physics, Oxford (United Kingdom)); McDougall, N.A. (National Lab. for High Energy Physics, Tsukuba, Ibaraki (Japan))
1992-07-09
We show that two well-known solutions to the strong CP problem, the axion and a massless quark, may be understood in terms of the mechanism recently proposed by Samuel where long-range interactions between topological charges may be responsible for the removal of CP violation. We explain how the axion and a QCD meson (identified as the {eta}' if all quarks are massless) suppress fluctuations in global topological charge by almost identical dynamical although the masses, couplings and relevant length scales are very different. Furthermore, we elucidate the precise origin of the {eta}' mass. (orig.).
DEFF Research Database (Denmark)
Seiller, Thomas
2016-01-01
Interaction graphs were introduced as a general, uniform, construction of dynamic models of linear logic, encompassing all Geometry of Interaction (GoI) constructions introduced so far. This series of work was inspired from Girard's hyperfinite GoI, and develops a quantitative approach that should...... be understood as a dynamic version of weighted relational models. Until now, the interaction graphs framework has been shown to deal with exponentials for the constrained system ELL (Elementary Linear Logic) while keeping its quantitative aspect. Adapting older constructions by Girard, one can clearly define...... "full" exponentials, but at the cost of these quantitative features. We show here that allowing interpretations of proofs to use continuous (yet finite in a measure-theoretic sense) sets of states, as opposed to earlier Interaction Graphs constructions were these sets of states were discrete (and finite...
DEFF Research Database (Denmark)
Deterding, Sebastian; Lucero, Andrés; Holopainen, Jussi
2015-01-01
Wherever the rapid evolution of interactive technologies disrupts standing situational norms, creates new, often unclear situational audiences, or crosses cultural boundaries, embarrassment is likely. This makes embarrassment a fundamental adoption and engagement hurdle, but also a creative design...
International Nuclear Information System (INIS)
Del Duca, V.; Marage, P.
1996-08-01
The general framework of diffractive deep inelastic scattering is introduced and reports given in the session on diffractive interactions at the international workshop on deep-inelastic scattering and related phenomena, Rome, April 1996, are presented. (orig.)
DEFF Research Database (Denmark)
Ingstrup, Mads
2003-01-01
This pattern describes the idea of making a user interface of discrete, reusable entities---here called interaction widgets. The idea behind widgets is described using two perspectives, that of the user and that of the developer. It is the forces from these two perspectives that are balanced...... in the pattern. The intended audience of the pattern is developers and researchers within the field of human computer interaction....
Cani , Marie-Paule; Bertails , Florence
2006-01-01
International audience; Processing interactions is one of the main challenges in hair animation. Indeed, in addition to the collisions with the body, an extremely large number of contacts with high friction rates are permanently taking place between individual hair strands. Simulating the latter is essential: without hair self-interactions, strands would cross each other during motion or come to rest at the same location, yielding unrealistic behavior and a visible lack of hair volume. This c...
Old and new problems in hypernuclei
International Nuclear Information System (INIS)
Gal, A.
1990-07-01
Recent developments in perceiving the overbinding problem for Λ hypernuclei are reviewed. Attention is focused on ΛNN interactions and the role these assume in the hypernuclear dynamics. Several possible versions for the Λ-spin dependence of dispersive ΛNN interaction terms in s-shell hypernuclei are derived, and their relevance to determining the Λ-nucleus spin dependence in p-shell hypernuclei is mentioned. (Author) (20 refs., tab., 4 figs.)
Wireless device connection problems and design solutions
Song, Ji-Won; Norman, Donald; Nam, Tek-Jin; Qin, Shengfeng
2016-09-01
Users, especially the non-expert users, commonly experience problems when connecting multiple devices with interoperability. While studies on multiple device connections are mostly concentrated on spontaneous device association techniques with a focus on security aspects, the research on user interaction for device connection is still limited. More research into understanding people is needed for designers to devise usable techniques. This research applies the Research-through-Design method and studies the non-expert users' interactions in establishing wireless connections between devices. The "Learning from Examples" concept is adopted to develop a study focus line by learning from the expert users' interaction with devices. This focus line is then used for guiding researchers to explore the non-expert users' difficulties at each stage of the focus line. Finally, the Research-through-Design approach is used to understand the users' difficulties, gain insights to design problems and suggest usable solutions. When connecting a device, the user is required to manage not only the device's functionality but also the interaction between devices. Based on learning from failures, an important insight is found that the existing design approach to improve single-device interaction issues, such as improvements to graphical user interfaces or computer guidance, cannot help users to handle problems between multiple devices. This study finally proposes a desirable user-device interaction in which images of two devices function together with a system image to provide the user with feedback on the status of the connection, which allows them to infer any required actions.
Problem solving skills for schizophrenia.
Xia, J; Li, Chunbo
2007-04-18
The severe and long-lasting symptoms of schizophrenia are often the cause of severe disability. Environmental stress such as life events and the practical problems people face in their daily can worsen the symptoms of schizophrenia. Deficits in problem solving skills in people with schizophrenia affect their independent and interpersonal functioning and impair their quality of life. As a result, therapies such as problem solving therapy have been developed to improve problem solving skills for people with schizophrenia. To review the effectiveness of problem solving therapy compared with other comparable therapies or routine care for those with schizophrenia. We searched the Cochrane Schizophrenia Group's Register (September 2006), which is based on regular searches of BIOSIS, CENTRAL, CINAHL, EMBASE, MEDLINE and PsycINFO. We inspected references of all identified studies for further trials. We included all clinical randomised trials comparing problem solving therapy with other comparable therapies or routine care. We extracted data independently. For homogenous dichotomous data we calculated random effects, relative risk (RR), 95% confidence intervals (CI) and, where appropriate, numbers needed to treat (NNT) on an intention-to-treat basis. For continuous data, we calculated weighted mean differences (WMD) using a random effects statistical model. We included only three small trials (n=52) that evaluated problem solving versus routine care, coping skills training or non-specific interaction. Inadequate reporting of data rendered many outcomes unusable. We were unable to undertake meta-analysis. Overall results were limited and inconclusive with no significant differences between treatment groups for hospital admission, mental state, behaviour, social skills or leaving the study early. No data were presented for global state, quality of life or satisfaction. We found insufficient evidence to confirm or refute the benefits of problem solving therapy as an additional
Interacting With Robots to Investigate the Bases of Social Interaction.
Sciutti, Alessandra; Sandini, Giulio
2017-12-01
Humans show a great natural ability at interacting with each other. Such efficiency in joint actions depends on a synergy between planned collaboration and emergent coordination, a subconscious mechanism based on a tight link between action execution and perception. This link supports phenomena as mutual adaptation, synchronization, and anticipation, which cut drastically the delays in the interaction and the need of complex verbal instructions and result in the establishment of joint intentions, the backbone of social interaction. From a neurophysiological perspective, this is possible, because the same neural system supporting action execution is responsible of the understanding and the anticipation of the observed action of others. Defining which human motion features allow for such emergent coordination with another agent would be crucial to establish more natural and efficient interaction paradigms with artificial devices, ranging from assistive and rehabilitative technology to companion robots. However, investigating the behavioral and neural mechanisms supporting natural interaction poses substantial problems. In particular, the unconscious processes at the basis of emergent coordination (e.g., unintentional movements or gazing) are very difficult-if not impossible-to restrain or control in a quantitative way for a human agent. Moreover, during an interaction, participants influence each other continuously in a complex way, resulting in behaviors that go beyond experimental control. In this paper, we propose robotics technology as a potential solution to this methodological problem. Robots indeed can establish an interaction with a human partner, contingently reacting to his actions without losing the controllability of the experiment or the naturalness of the interactive scenario. A robot could represent an "interactive probe" to assess the sensory and motor mechanisms underlying human-human interaction. We discuss this proposal with examples from our
Electromagnetic processes and interactions
International Nuclear Information System (INIS)
Scheck, F.
1983-01-01
The electron and muon are important tools in testing the structure of the fundamental electromagnetic interactions. On the other hand, if these interactions are known, they serve as ideal probes for the internal structure of complex hadronic targets such as nucleons and nuclei. Purely electromagnetic interactions play a distinctive role, for obvious experimental reasons: At low and intermediate energies the effective electromagnetic coupling is larger by many orders of magnitude than the weak couplings, so that electromagnetic processes are measurable to much higher accuracy than purely weak processes. The present chapter deals primarily with applications of charged leptons to problems of nucleon and nuclear structure, and to selected precision tests of quantum electrodynamics (QED) at low momentum transfers. In most of these applications the electromagnetic interactions effectively appear in the form of external fields in the leptonic particle's Dirac equation. This is the domain where the physics of (electromagnetically) interacting leptons can still be described in the framework of an effective, though relativistic, single particle theory. (orig.)
International Nuclear Information System (INIS)
Labaune, C.; Fuchs, J.; Bandulet, H.
2002-01-01
Imprint elimination, smoothing and preheat control are considerable problems in inertial fusion and their possible solution can be achieved by using low-density porous materials as a buffer in target design. The articles gathered in this document present various aspects of the laser-plasma interaction, among which we have noticed: -) numerical algorithmic improvements of the Vlasov solver toward the simulation of the laser-plasma interaction are proposed, -) the dependence of radiation temperatures and X-ray conversion efficiencies of hohlraum on the target structures and laser irradiation conditions are investigated, -) a study of laser interaction with ultra low-density (0,5 - 20 mg/cm 3 ) porous media analyzing backscattered light at incident laser frequency ω 0 and its harmonics 3*ω 0 /2 and 2*ω 0 is presented, -) investigations of laser interaction with solid targets and crater formation are carried out with the objective to determine the ablation loading efficiency, -) a self organization in an intense laser-driven plasma and the measure of the relative degree of order of the states in an open system based on the S-theorem are investigated, and -) the existence and stability of electromagnetic solitons generated in a relativistic interaction of an intense laser light with uniform under-dense cold plasma are studied
DEFF Research Database (Denmark)
Sørensen, Eva; Torfing, Jacob; Peters, B. Guy
Governance has become one of the most commonly used concepts in contemporary political science. It is, however, often used to mean a variety of different things. This book helps to clarify this conceptual muddle by concentrating on one variety of governance-interactive governance. The authors argue...... that although the state may remain important for many aspects of governing, interactions between state and society represent an important, and perhaps increasingly important, dimension of governance. These interactions may be with social actors such as networks, with market actors or with other governments......, but all these forms represent means of governing involving mixtures of state action with the actions of other entities.This book explores thoroughly this meaning of governance, and links it to broader questions of governance. In the process of explicating this dimension of governance the authors also...
International Nuclear Information System (INIS)
Luk'yanov, V.K.
1984-01-01
To study multiquark interactions (MQI) the data of experiments confirming the presence of 3q, 6q, 12q states in interacting nuclear nucleons, in hadron- and lepton-nuclear processes at high energies and high momentum transfers are considered. Experimental data on cumulative processes pointing to the existence of MQI are analyzed. Two-channel model of a nucleus (the model of interacting nucleons) in the theory of coupled channels is discussed. The behaviour of form factor of deuteron and NQI (6q) contributions to ed scattering as well as deep inelastic scattering on nuclei are studied. The data known as EMC effect are discussed. It is pointed out that introduction of the notion MQI and consideration of a nucleus as a system of nucleons with a low MQI addition will help to explain such processes as cumulative reactions, form factors of a deuteron and light nuclei, deep inelastic scattering on nuclei
Shutdown problems in large tokamaks
International Nuclear Information System (INIS)
Weldon, D.M.
1978-01-01
Some of the problems connected with a normal shutdown at the end of the burn phase (soft shutdown) and with a shutdown caused by disruptive instability (hard shutdown) have been considered. For a soft shutdown a cursory literature search was undertaken and methods for controlling the thermal wall loading were listed. Because shutdown computer codes are not widespread, some of the differences between start-up codes and shutdown codes were discussed along with program changes needed to change a start-up code to a shutdown code. For a hard shutdown, the major problems are large induced voltages in the ohmic-heating and equilibrium-field coils and high first wall erosion. A literature search of plasma-wall interactions was carried out. Phenomena that occur at the plasma-wall interface can be quite complicated. For example, material evaporated from the wall can form a virtual limiter or shield protecting the wall from major damage. Thermal gradients that occur during the interaction can produce currents whose associated magnetic field also helps shield the wall
Lavine method applied to three body problems
International Nuclear Information System (INIS)
Mourre, Eric.
1975-09-01
The methods presently proposed for the three body problem in quantum mechanics, using the Faddeev approach for proving the asymptotic completeness, come up against the presence of new singularities when the potentials considered v(α)(x(α)) for two-particle interactions decay less rapidly than /x(α)/ -2 ; and also when trials are made for solving the problem with a representation space whose dimension for a particle is lower than three. A method is given that allows the mathematical approach to be extended to three body problem, in spite of singularities. Applications are given [fr
Semidefinite linear complementarity problems
International Nuclear Information System (INIS)
Eckhardt, U.
1978-04-01
Semidefinite linear complementarity problems arise by discretization of variational inequalities describing e.g. elastic contact problems, free boundary value problems etc. In the present paper linear complementarity problems are introduced and the theory as well as the numerical treatment of them are described. In the special case of semidefinite linear complementarity problems a numerical method is presented which combines the advantages of elimination and iteration methods without suffering from their drawbacks. This new method has very attractive properties since it has a high degree of invariance with respect to the representation of the set of all feasible solutions of a linear complementarity problem by linear inequalities. By means of some practical applications the properties of the new method are demonstrated. (orig.) [de
Energy Technology Data Exchange (ETDEWEB)
Pan, Feng [Los Alamos National Laboratory; Kasiviswanathan, Shiva [Los Alamos National Laboratory
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.
Standard problems for structural computer codes
International Nuclear Information System (INIS)
Philippacopoulos, A.J.; Miller, C.A.; Costantino, C.J.
1985-01-01
BNL is investigating the ranges of validity of the analytical methods used to predict the behavior of nuclear safety related structures under accidental and extreme environmental loadings. During FY 85, the investigations were concentrated on special problems that can significantly influence the outcome of the soil structure interaction evaluation process. Specially, limitations and applicability of the standard interaction methods when dealing with lift-off, layering and water table effects, were investigated. This paper describes the work and the results obtained during FY 85 from the studies on lift-off, layering and water-table effects in soil-structure interaction
Noble, Joshua
2009-01-01
Make cool stuff. If you're a designer or artist without a lot of programming experience, this book will teach you to work with 2D and 3D graphics, sound, physical interaction, and electronic circuitry to create all sorts of interesting and compelling experiences -- online and off. Programming Interactivity explains programming and electrical engineering basics, and introduces three freely available tools created specifically for artists and designers: Processing, a Java-based programming language and environment for building projects on the desktop, Web, or mobile phonesArduino, a system t
International Nuclear Information System (INIS)
Eggleton, P.P.; Pringle, J.E.
1985-01-01
This volume contains 15 review articles in the field of binary stars. The subjects reviewed span considerably, from the shortest period of interacting binaries to the longest, symbiotic stars. Also included are articles on Algols, X-ray binaries and Wolf-Rayet stars (single and binary). Contents: Preface. List of Participants. Activity of Contact Binary Systems. Wolf-Rayet Stars and Binarity. Symbiotic Stars. Massive X-ray Binaries. Stars that go Hump in the Night: The SU UMa Stars. Interacting Binaries - Summing Up
Creativity for Problem Solvers
DEFF Research Database (Denmark)
Vidal, Rene Victor Valqui
2009-01-01
This paper presents some modern and interdisciplinary concepts about creativity and creative processes specially related to problem solving. Central publications related to the theme are briefly reviewed. Creative tools and approaches suitable to support problem solving are also presented. Finally......, the paper outlines the author’s experiences using creative tools and approaches to: Facilitation of problem solving processes, strategy development in organisations, design of optimisation systems for large scale and complex logistic systems, and creative design of software optimisation for complex non...
Perturbed asymptotically linear problems
Bartolo, R.; Candela, A. M.; Salvatore, A.
2012-01-01
The aim of this paper is investigating the existence of solutions of some semilinear elliptic problems on open bounded domains when the nonlinearity is subcritical and asymptotically linear at infinity and there is a perturbation term which is just continuous. Also in the case when the problem has not a variational structure, suitable procedures and estimates allow us to prove that the number of distinct crtitical levels of the functional associated to the unperturbed problem is "stable" unde...
The stochastic goodwill problem
Marinelli, Carlo
2003-01-01
Stochastic control problems related to optimal advertising under uncertainty are considered. In particular, we determine the optimal strategies for the problem of maximizing the utility of goodwill at launch time and minimizing the disutility of a stream of advertising costs that extends until the launch time for some classes of stochastic perturbations of the classical Nerlove-Arrow dynamics. We also consider some generalizations such as problems with constrained budget and with discretionar...
Bruce L. Parker
1991-01-01
As entomologists, we sometimes like to think of an insect pest problem as simply a problem with an insect and its host. Our jobs would be much easier if that were the case, but of course, it is never that simple. There are many other factors besides the insect, and each one must be fully considered to understand the problem and develop effective management solutions....
Special problems in the theory of elementary particle interactions
International Nuclear Information System (INIS)
Dumitru, D.R.
1978-01-01
The objectives of the thesis paper are: a) construction of multiparticle invariant amplitudes for arbitrary angular momenta. Consequently, the Poincare invariant quantities can be used, instead of the covariant ones without losing information: a total system of kinematic restraints for the holomorphic invariant amplitudes and for the invariant amplitudes with temperate distribution is described. b) development of spinorial amplitudes within unsaturated analiticity ranges by holomorphic invariant amplitudes and without restraints. c) finding a well-defined mathematical baring for the helicity amplitudes as distributions within the physical range. d) kinematic regulation of multiparticle helicity amplitudes and calculation of a full set of kinematic restraints for the regulated helicity amplitudes. (author)
Erroneous analyses of interactions in neuroscience: a problem of significance
Nieuwenhuis, S.; Forstmann, B.U.; Wagenmakers, E.-J.
2011-01-01
In theory, a comparison of two experimental effects requires a statistical test on their difference. In practice, this comparison is often based on an incorrect procedure involving two separate tests in which researchers conclude that effects differ when one effect is significant (P < 0.05) but the
Comment: Interactive Problem-Solving Interventions as Instrument of ...
African Journals Online (AJOL)
This structural and conceptual metamorphosis in the international conflict paradigm has required the international community to rethink the traditional and formal conflict management and third party intervention techniques and instruments such as negotiation and mediation. In the course of achieving these goals, conflict ...
Raffo Lecca, Eduardo
2014-01-01
This is a famous problem from the annals of literature in operations research. G. Dantzig in [1] refers to W.W. Jacobs with his paper "The Caterer Problem" Nav. Log Res. Quart. 1 1954; as well as Gaddum, Hoffman and Sokolowsky "On the Solution of the Caterer Problem" Naval Res Logist. Quart., Vol.1, No. 3, september, 1954, and William Prager "On the Caterer Problem" of Management Sci, Vol 3, No. 1 october 1956 and Management Sci, Vol 3, No. 2 january 1957. Subsequently both G. Hadley presents...
Araki,Naoki
2018-01-01
The Problem of Evil has been discussed as one of the major problems in monotheism. “Why does Almighty God allow evil to exist?” Various solutions to this problem have been proposed, including the Free Will Defence. But none of them is convincing. The Problem of Evil has an assumption, which is that God exists. One of the proofs of God’s existence is René Descartes’s Ontological Argument. But none of them is persuasive. Every logic has its own assumption, which needs to be verified. So this pr...
Singh, Devraj
2015-01-01
Numerical Problems in Physics, Volume 1 is intended to serve the need of the students pursuing graduate and post graduate courses in universities with Physics and Materials Science as subject including those appearing in engineering, medical, and civil services entrance examinations. KEY FEATURES: * 29 chapters on Optics, Wave & Oscillations, Electromagnetic Field Theory, Solid State Physics & Modern Physics * 540 solved numerical problems of various universities and ompetitive examinations * 523 multiple choice questions for quick and clear understanding of subject matter * 567 unsolved numerical problems for grasping concepts of the various topic in Physics * 49 Figures for understanding problems and concept
DEFF Research Database (Denmark)
Foss, Kirsten; Foss, Nicolai Juul
2006-01-01
as a general approach to problem solving. We apply these Simonian ideas to organisational issues, specifically new organisational forms. Specifically, Simonian ideas allow us to develop a morphology of new organisational forms and to point to some design problems that characterise these forms.......Two of Herbert Simon's best-known papers are 'The Architecture of Complexity' and 'The Structure of Ill-Structured Problems.' We discuss the neglected links between these two papers, highlighting the role of decomposition in the context of problems on which constraints have been imposed...
International Nuclear Information System (INIS)
Egorov, Yurii V
2013-01-01
We consider the classical problem on the tallest column which was posed by Euler in 1757. Bernoulli-Euler theory serves today as the basis for the design of high buildings. This problem is reduced to the problem of finding the potential for the Sturm-Liouville equation corresponding to the maximum of the first eigenvalue. The problem has been studied by many mathematicians but we give the first rigorous proof of the existence and uniqueness of the optimal column and we give new formulae which let us find it. Our method is based on a new approach consisting in the study of critical points of a related nonlinear functional. Bibliography: 6 titles.
Shielding benchmark problems, (2)
International Nuclear Information System (INIS)
Tanaka, Shun-ichi; Sasamoto, Nobuo; Oka, Yoshiaki; Shin, Kazuo; Tada, Keiko.
1980-02-01
Shielding benchmark problems prepared by Working Group of Assessment of Shielding Experiments in the Research Committee on Shielding Design in the Atomic Energy Society of Japan were compiled by Shielding Laboratory in Japan Atomic Energy Research Institute. Fourteen shielding benchmark problems are presented newly in addition to twenty-one problems proposed already, for evaluating the calculational algorithm and accuracy of computer codes based on discrete ordinates method and Monte Carlo method and for evaluating the nuclear data used in codes. The present benchmark problems are principally for investigating the backscattering and the streaming of neutrons and gamma rays in two- and three-dimensional configurations. (author)
Directory of Open Access Journals (Sweden)
Radovanović Saša Ž.
2014-01-01
Full Text Available The author explains the link between fundamental ontology and metontology in Heidegger's thought. In this context, he raises the question about art as a metontological problem. Then he goes to show that the problem of metontology stems from imanent transformation of fundamental ontology. In this sense, two aspects of the problem of existence assume relevance, namely, universality and radicalism. He draws the conclusion that metontology and art as its problem, as opposed to fundamental ontology, were not integrated into Heidegger's later thought.
Combinatorial problems and exercises
Lovász, László
2007-01-01
The main purpose of this book is to provide help in learning existing techniques in combinatorics. The most effective way of learning such techniques is to solve exercises and problems. This book presents all the material in the form of problems and series of problems (apart from some general comments at the beginning of each chapter). In the second part, a hint is given for each exercise, which contains the main idea necessary for the solution, but allows the reader to practice the techniques by completing the proof. In the third part, a full solution is provided for each problem. This book w
Cosmology and the weak interaction
Energy Technology Data Exchange (ETDEWEB)
Schramm, D.N. (Fermi National Accelerator Lab., Batavia, IL (USA)):(Chicago Univ., IL (USA))
1989-12-01
The weak interaction plays a critical role in modern Big Bang cosmology. This review will emphasize two of its most publicized cosmological connections: Big Bang nucleosynthesis and Dark Matter. The first of these is connected to the cosmological prediction of Neutrino Flavours, N{sub {nu}} {approximately} 3 which is now being confirmed at SLC and LEP. The second is interrelated to the whole problem of galaxy and structure formation in the universe. This review will demonstrate the role of the weak interaction both for dark matter candidates and for the problem of generating seeds to form structure. 87 refs., 3 figs., 5 tabs.
Cosmology and the weak interaction
International Nuclear Information System (INIS)
Schramm, D.N.
1989-12-01
The weak interaction plays a critical role in modern Big Bang cosmology. This review will emphasize two of its most publicized cosmological connections: Big Bang nucleosynthesis and Dark Matter. The first of these is connected to the cosmological prediction of Neutrino Flavours, N ν ∼ 3 which is now being confirmed at SLC and LEP. The second is interrelated to the whole problem of galaxy and structure formation in the universe. This review will demonstrate the role of the weak interaction both for dark matter candidates and for the problem of generating seeds to form structure. 87 refs., 3 figs., 5 tabs
Interactive Nonlinear Multiobjective Optimization Methods
Miettinen, Kaisa; Hakanen, Jussi; Podkopaev, Dmitry
2016-01-01
An overview of interactive methods for solving nonlinear multiobjective optimization problems is given. In interactive methods, the decision maker progressively provides preference information so that the most satisfactory Pareto optimal solution can be found for her or his. The basic features of several methods are introduced and some theoretical results are provided. In addition, references to modifications and applications as well as to other methods are indicated. As the...
International Nuclear Information System (INIS)
Fischer, J.; Kolar, P.; Kundrat, V.
1988-01-01
The proceedings contain invited lectures and papers presente at the symposium. Attention was devoted to hadron interactions a high energy in QCD, to the structure and decay of hadrons, the production of hadrons and supersymmetric particles in e + e - and ep collisions, to perturbation theory in quantum field theory, and new supersymmetric extensions of relativistic algebra. (Z.J
DEFF Research Database (Denmark)
Schoenau-Fog, Henrik; Reng, Lars
2015-01-01
This book constitutes the refereed proceedings of the 8th International Conference on Interactive Digital Storytelling, ICIDS 2015, held in Copenhagen, Denmark, in November/December 2015. The 18 revised full papers and 13 short papers presented together with 9 posters, 9 workshop descriptions, an...
International Nuclear Information System (INIS)
Finsterle, S.
1997-11-01
This report contains a collection of ITOUGH2 sample problems. It complements the ITOUGH2 User's Guide [Finsterle, 1997a], and the ITOUGH2 Command Reference [Finsterle, 1997b]. ITOUGH2 is a program for parameter estimation, sensitivity analysis, and uncertainty propagation analysis. It is based on the TOUGH2 simulator for non-isothermal multiphase flow in fractured and porous media [Preuss, 1987, 1991a]. The report ITOUGH2 User's Guide [Finsterle, 1997a] describes the inverse modeling framework and provides the theoretical background. The report ITOUGH2 Command Reference [Finsterle, 1997b] contains the syntax of all ITOUGH2 commands. This report describes a variety of sample problems solved by ITOUGH2. Table 1.1 contains a short description of the seven sample problems discussed in this report. The TOUGH2 equation-of-state (EOS) module that needs to be linked to ITOUGH2 is also indicated. Each sample problem focuses on a few selected issues shown in Table 1.2. ITOUGH2 input features and the usage of program options are described. Furthermore, interpretations of selected inverse modeling results are given. Problem 1 is a multipart tutorial, describing basic ITOUGH2 input files for the main ITOUGH2 application modes; no interpretation of results is given. Problem 2 focuses on non-uniqueness, residual analysis, and correlation structure. Problem 3 illustrates a variety of parameter and observation types, and describes parameter selection strategies. Problem 4 compares the performance of minimization algorithms and discusses model identification. Problem 5 explains how to set up a combined inversion of steady-state and transient data. Problem 6 provides a detailed residual and error analysis. Finally, Problem 7 illustrates how the estimation of model-related parameters may help compensate for errors in that model
Teachers' Personal Constructs on Problem Behaviour
H.A. Everaert; J.T.E. van Beukering; J.M.F. Touw
2005-01-01
Present study focuses on revealing and developing personal constructs regarding problem behaviour in classrooms. The main idea is that teachers opinions about their students and themselves influence the way they interact with them. Their thoughts and ideas about students - their personal constructs
Problem Representation on the Fringe of Institutions
Vallbé, J.J.
2014-01-01
Measuring the interaction between agents and institutions poses a number of challenges. The paper provides data and results from a project in political science aimed at representing the problem spaces described by organization members in depicting decision situations with high levels of procedural
Approximating multi-objective scheduling problems
Dabia, S.; Talbi, El-Ghazali; Woensel, van T.; Kok, de A.G.
2013-01-01
In many practical situations, decisions are multi-objective by nature. In this paper, we propose a generic approach to deal with multi-objective scheduling problems (MOSPs). The aim is to determine the set of Pareto solutions that represent the interactions between the different objectives. Due to
Hartree--Fock time-dependent problem
Energy Technology Data Exchange (ETDEWEB)
Bove, A; Fano, G [Bologna Univ. (Italy). Istituto di Fisica; Istituto Nazionale di Fisica Nucleare, Bologna (Italy)); Da Prato, G [Rome Univ. (Italy). Istituto di Matematica
1976-06-01
A previous result is generalized. An existence and uniqueness theorem is proved for the Hartree--Fock time-dependent problem in the case of a finite Fermi system interacting via a two body potential which is supposed to be dominated by the kinetic energy part of the one-particle Hamiltonian.
A game theoretic approach to assignment problems
Klijn, F.
2000-01-01
Game theory deals with the mathematical modeling and analysis of conflict and cooperation in the interaction of multiple decision makers. This thesis adopts two game theoretic methods to analyze a range of assignment problems that arise in various economic situations. The first method has as
Non-equilibrium fluctuation-induced interactions
International Nuclear Information System (INIS)
Dean, David S
2012-01-01
We discuss non-equilibrium aspects of fluctuation-induced interactions. While the equilibrium behavior of such interactions has been extensively studied and is relatively well understood, the study of these interactions out of equilibrium is relatively new. We discuss recent results on the non-equilibrium behavior of systems whose dynamics is of the dissipative stochastic type and identify a number of outstanding problems concerning non-equilibrium fluctuation-induced interactions.
Long, James D.
Schools need to meet unique problems through the development of special classroom management techniques. Factors which contribute to classroom problems include lack of supervision at home, broken homes, economic deprivation, and a desire for peer attention. The educational atmosphere should encourage creativity for both the student and the…
Inverse logarithmic potential problem
Cherednichenko, V G
1996-01-01
The Inverse and Ill-Posed Problems Series is a series of monographs publishing postgraduate level information on inverse and ill-posed problems for an international readership of professional scientists and researchers. The series aims to publish works which involve both theory and applications in, e.g., physics, medicine, geophysics, acoustics, electrodynamics, tomography, and ecology.
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…
Energy Technology Data Exchange (ETDEWEB)
Faulkner, D J [Australian National Univ., Canberra. Mount Stromlo and Siding Spring Observatories
1975-10-01
This paper reviews several recent attempts to solve the problem in terms of modified solar interior models. Some of these have removed the count rate discrepancy, but have violated other observational data for the sun. One successfully accounts for the Davis results at the expense of introducing an ad hoc correction with no current physical explanation. An introductory description of the problem is given.
Meng, G.; Heragu, S.S.; Heragu, S.S.; Zijm, Willem H.M.
2004-01-01
This paper addresses the reconfigurable layout problem, which differs from traditional, robust and dynamic layout problems mainly in two aspects: first, it assumes that production data are available only for the current and upcoming production period. Second, it considers queuing performance
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…
International Nuclear Information System (INIS)
Roxburgh, I.W.
1981-01-01
The problems posed by the low flux of neutrinos from the sun detected by Davis and coworkers are reviewed. Several proposals have been advanced to resolve these problems and the more reasonable (in the author's opinion) are presented. Recent claims that the neutrino may have finite mass are also considered. (orig.)
Cassidy, Jack
1991-01-01
Presents suggestions for teaching math word problems to elementary students. The strategies take into consideration differences between reading in math and reading in other areas. A problem-prediction game and four self-checking activities are included along with a magic password challenge. (SM)
Problems in baryon spectroscopy
Energy Technology Data Exchange (ETDEWEB)
Capstick, S. [Florida State Univ., Tallahassee, FL (United States)
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.
Problems Facing Rural Schools.
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…
2017-03-01
Borrajo and Raquel Fuentetaja, Universidad Carlos III de Madrid on the meta-level search architecture for finding good combinations of representations and...heuristics on a problem-by-problem basis. The other is with Carlos Linares also from Universidad Carlos III de Madrid on developing effective
Indian Academy of Sciences (India)
[G] Giannessi F, Theorems of alternative, quadratic programs and complementarity problems, in: Variational Inequalities and Complementarity Problems (eds) R W Cottle, F Giannessi and J L Lions (New York: Wiley) (1980) pp. 151±186. [K1] Kazmi K R, Existence of solutions for vector optimization, Appl. Math. Lett. 9 (1996).
Brouwer-Janse, M.D.
1991-01-01
Most formal problem-solving studies use verbal protocol and observational data of problem solvers working on a task. In user-centred product-design projects, observational studies of users are frequently used too. In the latter case, however, systematic control of conditions, indepth analysis and
Goldman, Iosif Ilich; Geilikman, B T
2006-01-01
This challenging book contains a comprehensive collection of problems in nonrelativistic quantum mechanics of varying degrees of difficulty. It features answers and completely worked-out solutions to each problem. Geared toward advanced undergraduates and graduate students, it provides an ideal adjunct to any textbook in quantum mechanics.
DEFF Research Database (Denmark)
Feenstra, Maria Monberg; Kirkeby, Mette Jørgine; Thygesen, Marianne
2018-01-01
Objectives Breastfeeding problems are common and associated with early cessation. Stilllength of postpartum hospital stay has been reduced. This leaves new mothers to establish breastfeeding at home with less support from health care professionals. The objective was to explore mothers’ perspectives...... on when breastfeeding problems were the most challenging and prominent early postnatal. The aim was also toidentify possible factors associated with the breastfeeding problems. Methods In a cross-sectional study, a mixed method approach was used to analyse postal survey data from 1437 mothers with full...... term singleton infants. Content analysis was used to analyse mothers’ open text descriptions of their most challenging breastfeeding problem. Multiple logistic regression was used to calculate odds ratios for early breastfeeding problems according to sociodemographic- and psychosocial factors. Results...
Wadsworth, A R
2017-01-01
This is a book of problems in abstract algebra for strong undergraduates or beginning graduate students. It can be used as a supplement to a course or for self-study. The book provides more variety and more challenging problems than are found in most algebra textbooks. It is intended for students wanting to enrich their learning of mathematics by tackling problems that take some thought and effort to solve. The book contains problems on groups (including the Sylow Theorems, solvable groups, presentation of groups by generators and relations, and structure and duality for finite abelian groups); rings (including basic ideal theory and factorization in integral domains and Gauss's Theorem); linear algebra (emphasizing linear transformations, including canonical forms); and fields (including Galois theory). Hints to many problems are also included.
Solved problems in electrochemistry
International Nuclear Information System (INIS)
Piron, D.L.
2004-01-01
This book presents calculated solutions to problems in fundamental and applied electrochemistry. It uses industrial data to illustrate scientific concepts and scientific knowledge to solve practical problems. It is subdivided into three parts. The first uses modern basic concepts, the second studies the scientific basis for electrode and electrolyte thermodynamics (including E-pH diagrams and the minimum energy involved in transformations) and the kinetics of rate processes (including the energy lost in heat and in parasite reactions). The third part treats larger problems in electrolysis and power generation, as well as in corrosion and its prevention. Each chapter includes three sections: the presentation of useful principles; some twenty problems with their solutions; and, a set of unsolved problems
The Guderley problem revisited
International Nuclear Information System (INIS)
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.
Structural Identification Problem
Directory of Open Access Journals (Sweden)
Suvorov Aleksei
2016-01-01
Full Text Available The identification problem of the existing structures though the Quasi-Newton and its modification, Trust region algorithms is discussed. For the structural problems, which could be represented by means of the mathematical modelling of the finite element code discussed method is extremely useful. The nonlinear minimization problem of the L2 norm for the structures with linear elastic behaviour is solved by using of the Optimization Toolbox of Matlab. The direct and inverse procedures for the composition of the desired function to minimize are illustrated for the spatial 3D truss structure as well as for the problem of plane finite elements. The truss identification problem is solved with 2 and 3 unknown parameters in order to compare the computational efforts and for the graphical purposes. The particular commands of the Matlab codes are present in this paper.
Schmüdgen, Konrad
2017-01-01
This advanced textbook provides a comprehensive and unified account of the moment problem. It covers the classical one-dimensional theory and its multidimensional generalization, including modern methods and recent developments. In both the one-dimensional and multidimensional cases, the full and truncated moment problems are carefully treated separately. Fundamental concepts, results and methods are developed in detail and accompanied by numerous examples and exercises. Particular attention is given to powerful modern techniques such as real algebraic geometry and Hilbert space operators. A wide range of important aspects are covered, including the Nevanlinna parametrization for indeterminate moment problems, canonical and principal measures for truncated moment problems, the interplay between Positivstellensätze and moment problems on semi-algebraic sets, the fibre theorem, multidimensional determinacy theory, operator-theoretic approaches, and the existence theory and important special topics of multidime...
Problems in equilibrium theory
Aliprantis, Charalambos D
1996-01-01
In studying General Equilibrium Theory the student must master first the theory and then apply it to solve problems. At the graduate level there is no book devoted exclusively to teaching problem solving. This book teaches for the first time the basic methods of proof and problem solving in General Equilibrium Theory. The problems cover the entire spectrum of difficulty; some are routine, some require a good grasp of the material involved, and some are exceptionally challenging. The book presents complete solutions to two hundred problems. In searching for the basic required techniques, the student will find a wealth of new material incorporated into the solutions. The student is challenged to produce solutions which are different from the ones presented in the book.
Interactive cinema : engagement and interaction
Vosmeer, M.; Schouten, B.; Mitchell, A.
2014-01-01
Technologies that were initially developed to be applied within the domain of video games are currently being used in experiments to explore their meaning and possibilities for cinema and cinema audiences. In this position paper we examine how narrativity, interactivity and engagement are mutually
Di Guilmi, Corrado; Gallegati, Mauro; Landini, Simone
2017-04-01
Preface; List of tables; List of figures, 1. Introduction; Part I. Methodological Notes and Tools: 2. The state space notion; 3. The master equation; Part II. Applications to HIA Based Models: 4. Financial fragility and macroeconomic dynamics I: heterogeneity and interaction; 5. Financial fragility and macroeconomic Dynamics II: learning; Part III. Conclusions: 6. Conclusive remarks; Part IV. Appendices and Complements: Appendix A: Complements to Chapter 3; Appendix B: Solving the ME to solve the ABM; Appendix C: Specifying transition rates; Index.
Neighbourhood and own social housing and early problem behaviour trajectories.
Flouri, Eirini; Midouhas, Emily; Tzatzaki, Konstantina
2015-02-01
To explore the roles of proportion of social rented housing in the neighbourhood ('neighbourhood social housing'), own housing being socially rented, and their interaction in early trajectories of emotional, conduct and hyperactivity symptoms. We tested three pathways of effects: family stress and maternal psychological distress, low quality parenting practices, and peer problems. We used data from 9,850 Millennium Cohort Study families who lived in England when the cohort children were aged 3. Children's emotional, conduct and hyperactivity problems were measured at ages 3, 5 and 7. Even after accounting for own social housing, neighbourhood social housing was related to all problems and their trajectories. Its association with conduct problems and hyperactivity was explained by selection. Selection also explained the effect of the interaction between neighbourhood and own social housing on hyperactivity, but not why children of social renter families living in neighbourhoods with lower concentrations of social housing followed a rising trajectory of emotional problems. The effects of own social housing, neighbourhood social housing and their interaction on emotional problems were robust. Peer problems explained the association of own social housing with hyperactivity. Neither selection nor the pathways we tested explained the association of own social housing with conduct problems, the association of neighbourhood social housing with their growth, or the association of neighbourhood social housing, own social housing and their interaction with emotional problems. Children of social renter families in neighbourhoods with a low concentration of social renters are particularly vulnerable to emotional problems.
Interactive Instruction in Bayesian Inference
DEFF Research Database (Denmark)
Khan, Azam; Breslav, Simon; Hornbæk, Kasper
2018-01-01
An instructional approach is presented to improve human performance in solving Bayesian inference problems. Starting from the original text of the classic Mammography Problem, the textual expression is modified and visualizations are added according to Mayer’s principles of instruction. These pri......An instructional approach is presented to improve human performance in solving Bayesian inference problems. Starting from the original text of the classic Mammography Problem, the textual expression is modified and visualizations are added according to Mayer’s principles of instruction....... These principles concern coherence, personalization, signaling, segmenting, multimedia, spatial contiguity, and pretraining. Principles of self-explanation and interactivity are also applied. Four experiments on the Mammography Problem showed that these principles help participants answer the questions...... that an instructional approach to improving human performance in Bayesian inference is a promising direction....
Brauer type embedding problems
Ledet, Arne
2005-01-01
This monograph is concerned with Galois theoretical embedding problems of so-called Brauer type with a focus on 2-groups and on finding explicit criteria for solvability and explicit constructions of the solutions. The advantage of considering Brauer type embedding problems is their comparatively simple condition for solvability in the form of an obstruction in the Brauer group of the ground field. This book presupposes knowledge of classical Galois theory and the attendant algebra. Before considering questions of reducing the embedding problems and reformulating the solvability criteria, the
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.
International Nuclear Information System (INIS)
Levy-Leblond, J.-M.
1990-01-01
This paper examines the problem of the reduction of the state vector in quantum theory. The author suggest that this issue ceases to cause difficulties if viewed from the correct perspective, for example by giving the state vector an auxiliary rather than fundamental status. He advocates changing the conceptual framework of quantum theory and working with quantons rather than particles and/or waves. He denies that reduction is a psychophysiological problem of observation, and raises the relevance of experimental apparatus. He concludes by venturing the suggestion that the problem of the reduction of the quantum state vector lies, not in quantum theory, but in classical perspectives. (UK)
Integrated network design and scheduling problems :
Energy Technology Data Exchange (ETDEWEB)
Nurre, Sarah G.; Carlson, Jeffrey J.
2014-01-01
We consider the class of integrated network design and scheduling problems. These problems focus on selecting and scheduling operations that will change the characteristics of a network, while being speci cally concerned with the performance of the network over time. Motivating applications of INDS problems include infrastructure restoration after extreme events and building humanitarian distribution supply chains. While similar models have been proposed, no one has performed an extensive review of INDS problems from their complexity, network and scheduling characteristics, information, and solution methods. We examine INDS problems under a parallel identical machine scheduling environment where the performance of the network is evaluated by solving classic network optimization problems. We classify that all considered INDS problems as NP-Hard and propose a novel heuristic dispatching rule algorithm that selects and schedules sets of arcs based on their interactions in the network. We present computational analysis based on realistic data sets representing the infrastructures of coastal New Hanover County, North Carolina, lower Manhattan, New York, and a realistic arti cial community CLARC County. These tests demonstrate the importance of a dispatching rule to arrive at near-optimal solutions during real-time decision making activities. We extend INDS problems to incorporate release dates which represent the earliest an operation can be performed and exible release dates through the introduction of specialized machine(s) that can perform work to move the release date earlier in time. An online optimization setting is explored where the release date of a component is not known.
Interaction of surface plasmon polaritons and acoustic waves inside an acoustic cavity.
Khokhlov, Nikolai; Knyazev, Grigoriy; Glavin, Boris; Shtykov, Yakov; Romanov, Oleg; Belotelov, Vladimir
2017-09-15
In this Letter, we introduce an approach for manipulation of active plasmon polaritons via acoustic waves at sub-terahertz frequency range. The acoustic structures considered are designed as phononic Fabry-Perot microresonators where mirrors are presented with an acoustic superlattice and the structure's surface, and a plasmonic grating is placed on top of the acoustic cavity so formed. It provides phonon localization in the vicinity of the plasmonic grating at frequencies within the phononic stop band enhancing phonon-light interaction. We consider phonon excitation by shining a femtosecond laser pulse on the plasmonic grating. Appropriate theoretical model was used to describe the acoustic process caused by the pump laser pulse in the GaAs/AlAs-based acoustic cavity with a gold grating on top. Strongest modulation is achieved upon excitation of propagating surface plasmon polaritons and hybridization of propagating and localized plasmons. The relative changes in the optical reflectivity of the structure are more than an order of magnitude higher than for the structure without the plasmonic film.
Some mass measurement problems
International Nuclear Information System (INIS)
Merritt, J.S.
1976-01-01
Concerning the problem of determining the thickness of a target, an uncomplicated approach is to measure its mass and area and take the quotient. This paper examines the mass measurement aspect of such an approach. (author)
The cosmological constant problem
International Nuclear Information System (INIS)
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
... damage your eyes. The most common problem is diabetic retinopathy. It is a leading cause of blindness ... You need a healthy retina to see clearly. Diabetic retinopathy damages the tiny blood vessels inside your ...
Rousseau, Madeleine; Ter Haar, D
1973-01-01
This collection of problems and accompanying solutions provide the reader with a full introduction to physical optics. The subject coverage is fairly traditional, with chapters on interference and diffraction, and there is a general emphasis on spectroscopy.
... teeth (periodontitis), canker sores, oral warts, fever blisters, oral candidiasis (thrush), hairy leukoplakia (which causes a rough, white patch on the tongue), and dental caries. Read More Publications Cover image Mouth Problems + HIV Publication files Download Language English PDF — ...
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)
DEFF Research Database (Denmark)
Reng, Lars; Schoenau-Fog, Henrik
2011-01-01
At Aalborg University’s department of Medialogy, we are utilizing the Problem Based Learning method to encourage students to solve game design problems by pushing the boundaries and designing innovative games. This paper is concerned with describing this method, how students employ it in various ...... projects and how they learn to analyse, design, and develop for innovation by using it. We will present various cases to exemplify the approach and focus on how the method engages students and aspires for innovation in digital entertainment and games.......At Aalborg University’s department of Medialogy, we are utilizing the Problem Based Learning method to encourage students to solve game design problems by pushing the boundaries and designing innovative games. This paper is concerned with describing this method, how students employ it in various...
Neutrosophic Integer Programming Problem
Directory of Open Access Journals (Sweden)
Mai Mohamed
2017-02-01
Full Text Available In this paper, we introduce the integer programming in neutrosophic environment, by considering coffecients of problem as a triangulare neutrosophic numbers. The degrees of acceptance, indeterminacy and rejection of objectives are simultaneously considered.
Nash, Jr, John Forbes
2016-01-01
The goal in putting together this unique compilation was to present the current status of the solutions to some of the most essential open problems in pure and applied mathematics. Emphasis is also given to problems in interdisciplinary research for which mathematics plays a key role. This volume comprises highly selected contributions by some of the most eminent mathematicians in the international mathematical community on longstanding problems in very active domains of mathematical research. A joint preface by the two volume editors is followed by a personal farewell to John F. Nash, Jr. written by Michael Th. Rassias. An introduction by Mikhail Gromov highlights some of Nash’s legendary mathematical achievements. The treatment in this book includes open problems in the following fields: algebraic geometry, number theory, analysis, discrete mathematics, PDEs, differential geometry, topology, K-theory, game theory, fluid mechanics, dynamical systems and ergodic theory, cryptography, theoretical computer sc...
[Current problems of deontology].
Dimov, A S
2010-01-01
The scope of knowledge in medical ethics continues to extend. Deontology as a science needs systematization of the accumulated data. This review may give impetus to classification of problems pertaining to this important area of medical activity.
... the Word Shop AAP Find a Pediatrician Ages & Stages Prenatal Baby Toddler Preschool Gradeschool Fitness Nutrition Puberty School Teen Young Adult Healthy Children > Ages & Stages > Gradeschool > School > Health Problems at School Ages & Stages ...
Challenging problems in geometry
Posamentier, Alfred S
1996-01-01
Collection of nearly 200 unusual problems dealing with congruence and parallelism, the Pythagorean theorem, circles, area relationships, Ptolemy and the cyclic quadrilateral, collinearity and concurrency and more. Arranged in order of difficulty. Detailed solutions.
A nonlinear oscillatory problem
International Nuclear Information System (INIS)
Zhou Qingqing.
1991-10-01
We have studied the nonlinear oscillatory problem of orthotropic cylindrical shell, we have analyzed the character of the oscillatory system. The stable condition of the oscillatory system has been given. (author). 6 refs
International Nuclear Information System (INIS)
Luest, R.
1977-01-01
The development in the FRG is portrayed. Illustrated by a particular example, the problems of basic research and of the scientists are presented looking back, looking at the present, and into the future. (WB) [de
International Nuclear Information System (INIS)
Kumar, N.
1984-07-01
Quantum first passage problem (QUIPP) is formulated and solved in terms of a constrained Feynman path integral. The related paradox of blocking of unitary evolution by continuous observation on the system implicit in QUIPP is briefly discussed. (author)
Teaching Creative Problem Solving.
Christensen, Kip W.; Martin, Loren
1992-01-01
Interpersonal and cognitive skills, adaptability, and critical thinking can be developed through problem solving and cooperative learning in technology education. These skills have been identified as significant needs of the workplace as well as for functioning in society. (SK)
International Nuclear Information System (INIS)
Savvidi, G.K.
1985-01-01
Such a viewpoint is proposed for separation of the physical quantities into observable and unobservable ones, when the latters are connected with the Hermitian operator for which the eigenvalue problem is unsolvable
Street photography as social interaction
Directory of Open Access Journals (Sweden)
Andrea Mubi Brighenti
2009-06-01
Full Text Available Street photographers know quite well that taking a picture is a form of social interaction. The birth of this genre of photography, they have been discussing at length about the ethical problems involved in taking pictures of personal strangers in public places without asking permission.
Interactive behavior in conflict situations
Quant, M.
2006-01-01
This thesis deals with interactive behavior in conflict situations. The first chapters consider several issues in relation to bankruptcy theory. Thereafter, several operations research problems are modeled within the framework of cooperative game theory. The main focus is on what is optimal for a
140 CIRCULAR INTERACTION BETWEEN LINGUISTIC ...
African Journals Online (AJOL)
economy. Although a country or administrative district should have one or more official languages for obvious reasons, Nelde (1991) proposes that the ... circular interaction between linguistic departments and language departments. Finding an answer to' Plato's abovementioned problem entails that as many languages as ...
INTERACTION ANALYSIS--RECENT DEVELOPMENTS.
AMIDON, EDMUND
MODIFICATION OF FLANDERS' INTERACTION ANALYSIS IS PROPOSED TO ENCOMPASS SOME FEATURES OF RELATED SYSTEMS AND TO PROVIDE A SPECIFIC FEEDBACK TOOL FOR ANALYZING ONE'S OWN TEACHING, FORMULATING QUESTIONS, OBSERVING TEACHING PATTERNS, DIAGNOSING TEACHING PROBLEMS, AND FOR ROLE-PLAYING IN THE COLLEGE CLASSROOM. FLANDERS' 10 CATEGORIES ARE DIVIDED INTO…
Congested Aggregation via Newtonian Interaction
Craig, Katy; Kim, Inwon; Yao, Yao
2018-01-01
We consider a congested aggregation model that describes the evolution of a density through the competing effects of nonlocal Newtonian attraction and a hard height constraint. This provides a counterpoint to existing literature on repulsive-attractive nonlocal interaction models, where the repulsive effects instead arise from an interaction kernel or the addition of diffusion. We formulate our model as the Wasserstein gradient flow of an interaction energy, with a penalization to enforce the constraint on the height of the density. From this perspective, the problem can be seen as a singular limit of the Keller-Segel equation with degenerate diffusion. Two key properties distinguish our problem from previous work on height constrained equations: nonconvexity of the interaction kernel (which places the model outside the scope of classical gradient flow theory) and nonlocal dependence of the velocity field on the density (which causes the problem to lack a comparison principle). To overcome these obstacles, we combine recent results on gradient flows of nonconvex energies with viscosity solution theory. We characterize the dynamics of patch solutions in terms of a Hele-Shaw type free boundary problem and, using this characterization, show that in two dimensions patch solutions converge to a characteristic function of a disk in the long-time limit, with an explicit rate on the decay of the energy. We believe that a key contribution of the present work is our blended approach, combining energy methods with viscosity solution theory.
Accelerator shielding benchmark problems
International Nuclear Information System (INIS)
Hirayama, H.; Ban, S.; Nakamura, T.
1993-01-01
Accelerator shielding benchmark problems prepared by Working Group of Accelerator Shielding in the Research Committee on Radiation Behavior in the Atomic Energy Society of Japan were compiled by Radiation Safety Control Center of National Laboratory for High Energy Physics. Twenty-five accelerator shielding benchmark problems are presented for evaluating the calculational algorithm, the accuracy of computer codes and the nuclear data used in codes. (author)