[Similarity system theory to evaluate similarity of chromatographic fingerprints of traditional Chinese medicine].

Science.gov (United States)

Liu, Yongsuo; Meng, Qinghua; Jiang, Shumin; Hu, Yuzhu

2005-03-01

The similarity evaluation of the fingerprints is one of the most important problems in the quality control of the traditional Chinese medicine (TCM). Similarity measures used to evaluate the similarity of the common peaks in the chromatogram of TCM have been discussed. Comparative studies were carried out among correlation coefficient, cosine of the angle and an improved extent similarity method using simulated data and experimental data. Correlation coefficient and cosine of the angle are not sensitive to the differences of the data set. They are still not sensitive to the differences of the data even after normalization. According to the similarity system theory, an improved extent similarity method was proposed. The improved extent similarity is more sensitive to the differences of the data sets than correlation coefficient and cosine of the angle. And the character of the data sets needs not to be changed compared with log-transformation. The improved extent similarity can be used to evaluate the similarity of the chromatographic fingerprints of TCM.

Multidimensional Riemann problem with self-similar internal structure. Part II - Application to hyperbolic conservation laws on unstructured meshes

Science.gov (United States)

Balsara, Dinshaw S.; Dumbser, Michael

2015-04-01

Multidimensional Riemann solvers that have internal sub-structure in the strongly-interacting state have been formulated recently (D.S. Balsara (2012, 2014) [5,16]). Any multidimensional Riemann solver operates at the grid vertices and takes as its input all the states from its surrounding elements. It yields as its output an approximation of the strongly interacting state, as well as the numerical fluxes. The multidimensional Riemann problem produces a self-similar strongly-interacting state which is the result of several one-dimensional Riemann problems interacting with each other. To compute this strongly interacting state and its higher order moments we propose the use of a Galerkin-type formulation to compute the strongly interacting state and its higher order moments in terms of similarity variables. The use of substructure in the Riemann problem reduces numerical dissipation and, therefore, allows a better preservation of flow structures, like contact and shear waves. In this second part of a series of papers we describe how this technique is extended to unstructured triangular meshes. All necessary details for a practical computer code implementation are discussed. In particular, we explicitly present all the issues related to computational geometry. Because these Riemann solvers are Multidimensional and have Self-similar strongly-Interacting states that are obtained by Consistency with the conservation law, we call them MuSIC Riemann solvers. (A video introduction to multidimensional Riemann solvers is available on http://www.elsevier.com/xml/linking-roles/text/html". The MuSIC framework is sufficiently general to handle general nonlinear systems of hyperbolic conservation laws in multiple space dimensions. It can also accommodate all self-similar one-dimensional Riemann solvers and subsequently produces a multidimensional version of the same. In this paper we focus on unstructured triangular meshes. As examples of different systems of conservation laws we

Similarities and Differences between Individuals Seeking Treatment for Gambling Problems vs. Alcohol and Substance Use Problems in Relation to the Progressive Model of Self-stigma

Directory of Open Access Journals (Sweden)

Belle Gavriel-Fried

2017-06-01

Full Text Available Aims: People with gambling as well as substance use problems who are exposed to public stigmatization may internalize and apply it to themselves through a mechanism known as self-stigma. This study implemented the Progressive Model for Self-Stigma which consists four sequential interrelated stages: awareness, agreement, application and harm on three groups of individuals with gambling, alcohol and other substance use problems. It explored whether the two guiding assumptions of this model (each stage is precondition for the following stage which are trickle-down in nature, and correlations between proximal stages should be larger than correlations between more distant stages would differentiate people with gambling problems from those with alcohol and other substance use problems in terms of their patterns of self-stigma and in terms of the stages in the model.Method: 37 individuals with gambling problems, 60 with alcohol problems and 51 with drug problems who applied for treatment in rehabilitation centers in Israel in 2015–2016 were recruited. They completed the Self-stigma of Mental Illness Scale-Short Form which was adapted by changing the term “mental health” to gambling, alcohol or drugs, and the DSM-5-diagnostic criteria for gambling, alcohol or drug disorder.Results: The assumptions of the model were broadly confirmed: a repeated measures ANCOVA revealed that in all three groups there was a difference between first two stages (aware and agree and the latter stages (apply and harm. In addition, the gambling group differed from the drug use and alcohol groups on the awareness stage: individuals with gambling problems were less likely to be aware of stigma than people with substance use or alcohol problems.Conclusion: The internalization of stigma among individuals with gambling problems tends to work in a similar way as for those with alcohol or drug problems. The differences between the gambling group and the alcohol and other

Self-similar continued root approximants

International Nuclear Information System (INIS)

Gluzman, S.; Yukalov, V.I.

2012-01-01

A novel method of summing asymptotic series is advanced. Such series repeatedly arise when employing perturbation theory in powers of a small parameter for complicated problems of condensed matter physics, statistical physics, and various applied problems. The method is based on the self-similar approximation theory involving self-similar root approximants. The constructed self-similar continued roots extrapolate asymptotic series to finite values of the expansion parameter. The self-similar continued roots contain, as a particular case, continued fractions and Padé approximants. A theorem on the convergence of the self-similar continued roots is proved. The method is illustrated by several examples from condensed-matter physics.

Culture and postpartum mood problems: similarities and differences in the experiences of first- and second-generation Canadian women.

Science.gov (United States)

Mamisachvili, Lana; Ardiles, Paola; Mancewicz, Grazyna; Thompson, Sherry; Rabin, Kapri; Ross, Lori E

2013-04-01

Few studies have examined the role of culture in a woman's experience of postpartum mood problems (PPMP). This study explored differences and similarities in experiences of PPMP between first- and second-generation Canadian women. In this exploratory qualitative study, we interviewed nine first-generation and eight second-generation women who were clients of the Women's Health Centre at St. Joseph's Health Centre in Toronto, Canada. Using semistructured interviews, we explored how women perceived and experienced PPMP. Four themes reflected cultural issues: PPMP stigma, relationship with parents/in-laws, internalization of society's expectations of motherhood, and identity issues/relationship with self. The results of this study contribute to a limited literature on possible contributing factors to PPMP and can inform development of resources for delivering culturally appropriate mental health care for women dealing with PPMP.

Mobile Device Impairment ... Similar Problems, Similar Solutions?

Science.gov (United States)

Harper, Simon; Yesilada, Yeliz; Chen, Tianyi

2011-01-01

Previous studies have defined a new type of impairment in which an able-bodied user's behaviour is impaired by both the characteristics of a device and the environment in which it is used. This behavioural change is defined as a situationally-induced impairment and is often associated with small devices used in a mobile setting or constrained…

Self-similarity in the equation of motion of a ship

Directory of Open Access Journals (Sweden)

Gyeong Joong Lee

2014-06-01

Full Text Available If we want to analyze the motion of a body in fluid, we should use rigid-body dynamics and fluid dynamics together. Even if the rigid-body and fluid dynamics are each self-consistent, there arises the problem of self-similar structure in the equation of motion when the two dynamics are coupled with each other. When the added mass is greater than the mass of a body, the calculated motion is divergent because of its self-similar structure. This study showed that the above problem is an inherent problem. This problem of self-similar structure may arise in the equation of motion in which the fluid dynamic forces are treated as external forces on the right hand side of the equation. A reconfiguration technique for the equation of motion using pseudo-added-mass was proposed to resolve the self-similar structure problem; specifically for the case when the fluid force is expressed by integration of the fluid pressure.

Processes of Similarity Judgment

Science.gov (United States)

Larkey, Levi B.; Markman, Arthur B.

2005-01-01

Similarity underlies fundamental cognitive capabilities such as memory, categorization, decision making, problem solving, and reasoning. Although recent approaches to similarity appreciate the structure of mental representations, they differ in the processes posited to operate over these representations. We present an experiment that…

Molecular similarity measures.

Science.gov (United States)

Maggiora, Gerald M; Shanmugasundaram, Veerabahu

2011-01-01

Molecular similarity is a pervasive concept in chemistry. It is essential to many aspects of chemical reasoning and analysis and is perhaps the fundamental assumption underlying medicinal chemistry. Dissimilarity, the complement of similarity, also plays a major role in a growing number of applications of molecular diversity in combinatorial chemistry, high-throughput screening, and related fields. How molecular information is represented, called the representation problem, is important to the type of molecular similarity analysis (MSA) that can be carried out in any given situation. In this work, four types of mathematical structure are used to represent molecular information: sets, graphs, vectors, and functions. Molecular similarity is a pairwise relationship that induces structure into sets of molecules, giving rise to the concept of chemical space. Although all three concepts - molecular similarity, molecular representation, and chemical space - are treated in this chapter, the emphasis is on molecular similarity measures. Similarity measures, also called similarity coefficients or indices, are functions that map pairs of compatible molecular representations that are of the same mathematical form into real numbers usually, but not always, lying on the unit interval. This chapter presents a somewhat pedagogical discussion of many types of molecular similarity measures, their strengths and limitations, and their relationship to one another. An expanded account of the material on chemical spaces presented in the first edition of this book is also provided. It includes a discussion of the topography of activity landscapes and the role that activity cliffs in these landscapes play in structure-activity studies.

Information filtering based on transferring similarity.

Science.gov (United States)

Sun, Duo; Zhou, Tao; Liu, Jian-Guo; Liu, Run-Ran; Jia, Chun-Xiao; Wang, Bing-Hong

2009-07-01

In this Brief Report, we propose an index of user similarity, namely, the transferring similarity, which involves all high-order similarities between users. Accordingly, we design a modified collaborative filtering algorithm, which provides remarkably higher accurate predictions than the standard collaborative filtering. More interestingly, we find that the algorithmic performance will approach its optimal value when the parameter, contained in the definition of transferring similarity, gets close to its critical value, before which the series expansion of transferring similarity is convergent and after which it is divergent. Our study is complementary to the one reported in [E. A. Leicht, P. Holme, and M. E. J. Newman, Phys. Rev. E 73, 026120 (2006)], and is relevant to the missing link prediction problem.

Lipschitz equivalence of self-similar sets with touching structures

International Nuclear Information System (INIS)

Ruan, Huo-Jun; Wang, Yang; Xi, Li-Feng

2014-01-01

Lipschitz equivalence of self-similar sets is an important area in the study of fractal geometry. It is known that two dust-like self-similar sets with the same contraction ratios are always Lipschitz equivalent. However, when self-similar sets have touching structures the problem of Lipschitz equivalence becomes much more challenging and intriguing at the same time. So far, all the known results only cover self-similar sets in R with no more than three branches. In this study we establish results for the Lipschitz equivalence of self-similar sets with touching structures in R with arbitrarily many branches. Key to our study is the introduction of a geometric condition for self-similar sets called substitutable. (paper)

Study on sociological approach to resolve maintenance related social problems

International Nuclear Information System (INIS)

Aoki, Takayuki

2007-01-01

This study proposes a sociological approach to resolve maintenance related social problems. As a result of consideration, the followings were found. (1) In general, solutions to some kinds of questions can be deduced from basic laws using some theories or methodologies in the field of the natural science or engineering. The approach to resolve maintenance related social problems is similar to the approach in the natural science or engineering. (2) The points of view based on fundamental human rights, market principles and community principles, and so on, are very important in resolving maintenance related social problems and can be placed as theories or tools for resolution. (3) If such theories or tools for resolving maintenance related social problems as described above are systematically prepared, it is estimated that it becomes very much easier to resolve maintenance related social problems. (author)

Compressional Alfven Eigenmode Similarity Study

Science.gov (United States)

Heidbrink, W. W.; Fredrickson, E. D.; Gorelenkov, N. N.; Rhodes, T. L.

2004-11-01

NSTX and DIII-D are nearly ideal for Alfven eigenmode (AE) similarity experiments, having similar neutral beams, fast-ion to Alfven speed v_f/v_A, fast-ion pressure, and shape of the plasma, but with a factor of 2 difference in the major radius. Toroidicity-induced AE with ˜100 kHz frequencies were compared in an earlier study [1]; this paper focuses on higher frequency AE with f ˜ 1 MHz. Compressional AE (CAE) on NSTX have a polarization, dependence on the fast-ion distribution function, frequency scaling, and low-frequency limit that are qualitatively consistent with CAE theory [2]. Global AE (GAE) are also observed. On DIII-D, coherent modes in this frequency range are observed during low-field (0.6 T) similarity experiments. Experiments will compare the CAE stability limits on DIII-D with the NSTX stability limits, with the aim of determining if CAE will be excited by alphas in a reactor. Predicted differences in the frequency splitting Δ f between excited modes will also be used. \\vspace0.25em [1] W.W. Heidbrink, et al., Plasmas Phys. Control. Fusion 45, 983 (2003). [2] E.D. Fredrickson, et al., Princeton Plasma Physics Laboratory Report PPPL-3955 (2004).

Study the Problem.

Science.gov (United States)

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)

Optimizing top precision performance measure of content-based image retrieval by learning similarity function

KAUST Repository

Liang, Ru-Ze

2017-04-24

In this paper we study the problem of content-based image retrieval. In this problem, the most popular performance measure is the top precision measure, and the most important component of a retrieval system is the similarity function used to compare a query image against a database image. However, up to now, there is no existing similarity learning method proposed to optimize the top precision measure. To fill this gap, in this paper, we propose a novel similarity learning method to maximize the top precision measure. We model this problem as a minimization problem with an objective function as the combination of the losses of the relevant images ranked behind the top-ranked irrelevant image, and the squared Frobenius norm of the similarity function parameter. This minimization problem is solved as a quadratic programming problem. The experiments over two benchmark data sets show the advantages of the proposed method over other similarity learning methods when the top precision is used as the performance measure.

Optimizing top precision performance measure of content-based image retrieval by learning similarity function

KAUST Repository

Liang, Ru-Ze; Shi, Lihui; Wang, Haoxiang; Meng, Jiandong; Wang, Jim Jing-Yan; Sun, Qingquan; Gu, Yi

2017-01-01

In this paper we study the problem of content-based image retrieval. In this problem, the most popular performance measure is the top precision measure, and the most important component of a retrieval system is the similarity function used to compare a query image against a database image. However, up to now, there is no existing similarity learning method proposed to optimize the top precision measure. To fill this gap, in this paper, we propose a novel similarity learning method to maximize the top precision measure. We model this problem as a minimization problem with an objective function as the combination of the losses of the relevant images ranked behind the top-ranked irrelevant image, and the squared Frobenius norm of the similarity function parameter. This minimization problem is solved as a quadratic programming problem. The experiments over two benchmark data sets show the advantages of the proposed method over other similarity learning methods when the top precision is used as the performance measure.

Phishing Detection: Analysis of Visual Similarity Based Approaches

Directory of Open Access Journals (Sweden)

Ankit Kumar Jain

2017-01-01

Full Text Available Phishing is one of the major problems faced by cyber-world and leads to financial losses for both industries and individuals. Detection of phishing attack with high accuracy has always been a challenging issue. At present, visual similarities based techniques are very useful for detecting phishing websites efficiently. Phishing website looks very similar in appearance to its corresponding legitimate website to deceive users into believing that they are browsing the correct website. Visual similarity based phishing detection techniques utilise the feature set like text content, text format, HTML tags, Cascading Style Sheet (CSS, image, and so forth, to make the decision. These approaches compare the suspicious website with the corresponding legitimate website by using various features and if the similarity is greater than the predefined threshold value then it is declared phishing. This paper presents a comprehensive analysis of phishing attacks, their exploitation, some of the recent visual similarity based approaches for phishing detection, and its comparative study. Our survey provides a better understanding of the problem, current solution space, and scope of future research to deal with phishing attacks efficiently using visual similarity based approaches.

Modeling the angular motion dynamics of spacecraft with a magnetic attitude control system based on experimental studies and dynamic similarity

Science.gov (United States)

Kulkov, V. M.; Medvedskii, A. L.; Terentyev, V. V.; Firsyuk, S. O.; Shemyakov, A. O.

2017-12-01

The problem of spacecraft attitude control using electromagnetic systems interacting with the Earth's magnetic field is considered. A set of dimensionless parameters has been formed to investigate the spacecraft orientation regimes based on dynamically similar models. The results of experimental studies of small spacecraft with a magnetic attitude control system can be extrapolated to the in-orbit spacecraft motion control regimes by using the methods of the dimensional and similarity theory.

Benchmark Problems of the Geothermal Technologies Office Code Comparison Study

Energy Technology Data Exchange (ETDEWEB)

White, Mark D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Podgorney, Robert [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Kelkar, Sharad M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); McClure, Mark W. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Danko, George [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Ghassemi, Ahmad [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Fu, Pengcheng [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Bahrami, Davood [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Barbier, Charlotte [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Cheng, Qinglu [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Chiu, Kit-Kwan [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Detournay, Christine [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Elsworth, Derek [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Fang, Yi [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Furtney, Jason K. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Gan, Quan [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Gao, Qian [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Guo, Bin [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Hao, Yue [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Horne, Roland N. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Huang, Kai [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Im, Kyungjae [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Norbeck, Jack [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Rutqvist, Jonny [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Safari, M. R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Sesetty, Varahanaresh [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Sonnenthal, Eric [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Tao, Qingfeng [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); White, Signe K. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Wong, Yang [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Xia, Yidong [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

2016-12-02

A diverse suite of numerical simulators is currently being applied to predict or understand the performance of enhanced geothermal systems (EGS). To build confidence and identify critical development needs for these analytical tools, the United States Department of Energy, Geothermal Technologies Office has sponsored a Code Comparison Study (GTO-CCS), with participants from universities, industry, and national laboratories. A principal objective for the study was to create a community forum for improvement and verification of numerical simulators for EGS modeling. Teams participating in the study were those representing U.S. national laboratories, universities, and industries, and each team brought unique numerical simulation capabilities to bear on the problems. Two classes of problems were developed during the study, benchmark problems and challenge problems. The benchmark problems were structured to test the ability of the collection of numerical simulators to solve various combinations of coupled thermal, hydrologic, geomechanical, and geochemical processes. This class of problems was strictly defined in terms of properties, driving forces, initial conditions, and boundary conditions. Study participants submitted solutions to problems for which their simulation tools were deemed capable or nearly capable. Some participating codes were originally developed for EGS applications whereas some others were designed for different applications but can simulate processes similar to those in EGS. Solution submissions from both were encouraged. In some cases, participants made small incremental changes to their numerical simulation codes to address specific elements of the problem, and in other cases participants submitted solutions with existing simulation tools, acknowledging the limitations of the code. The challenge problems were based on the enhanced geothermal systems research conducted at Fenton Hill, near Los Alamos, New Mexico, between 1974 and 1995. The problems

The arithmetic problem size effect in children: an event-related potential study

Directory of Open Access Journals (Sweden)

Leen eVan Beek

2014-09-01

Full Text Available This study used for the first time event-related potentials (ERPs to examine the well-known arithmetic problem size effect in children. The electrophysiological correlates of this problem size effect have been well documented in adults, but such information in children is lacking. In the present study, 22 typically developing 12-year-olds were asked to solve single-digit addition problems of small (sum ≤ 10 and large problem size (sum > 10 and to speak the solution into a voice key while ERPs were recorded. Children displayed similar early and late components compared to previous adult studies on the problem size effect. There was no effect of problem size on the early components P1, N1 and P2. The peak amplitude of the N2 component showed more negative potentials on left and right anterior electrodes for large additions compared to small additions, which might reflect differences in attentional and working memory resources between large and small problems. The mean amplitude of the late positivity component (LPC, which follows the N2, was significantly larger for large than for small additions at right parieto-occipital electrodes, in line with previous adult data. The ERPs of the problem size effect during arithmetic might be a useful neural marker for future studies on fact retrieval impairments in children with mathematical difficulties.

Notions of similarity for systems biology models.

Science.gov (United States)

Henkel, Ron; Hoehndorf, Robert; Kacprowski, Tim; Knüpfer, Christian; Liebermeister, Wolfram; Waltemath, Dagmar

2018-01-01

Systems biology models are rapidly increasing in complexity, size and numbers. When building large models, researchers rely on software tools for the retrieval, comparison, combination and merging of models, as well as for version control. These tools need to be able to quantify the differences and similarities between computational models. However, depending on the specific application, the notion of 'similarity' may greatly vary. A general notion of model similarity, applicable to various types of models, is still missing. Here we survey existing methods for the comparison of models, introduce quantitative measures for model similarity, and discuss potential applications of combined similarity measures. To frame model comparison as a general problem, we describe a theoretical approach to defining and computing similarities based on a combination of different model aspects. The six aspects that we define as potentially relevant for similarity are underlying encoding, references to biological entities, quantitative behaviour, qualitative behaviour, mathematical equations and parameters and network structure. We argue that future similarity measures will benefit from combining these model aspects in flexible, problem-specific ways to mimic users' intuition about model similarity, and to support complex model searches in databases. © The Author 2016. Published by Oxford University Press.

A nonlinear eigenvalue problem for self-similar spherical force-free magnetic fields

Energy Technology Data Exchange (ETDEWEB)

Lerche, I. [Institut für Geowissenschaften, Naturwissenschaftliche Fakultät III, Martin-Luther Universität, D-06099 Halle (Germany); Low, B. C. [High Altitude Observatory, National Center for Atmospheric Research, Boulder, Colorado 80307 (United States)

2014-10-15

An axisymmetric force-free magnetic field B(r, θ) in spherical coordinates is defined by a function r sin θB{sub φ}=Q(A) relating its azimuthal component to its poloidal flux-function A. The power law r sin θB{sub φ}=aA|A|{sup 1/n}, n a positive constant, admits separable fields with A=(A{sub n}(θ))/(r{sup n}) , posing a nonlinear boundary-value problem for the constant parameter a as an eigenvalue and A{sub n}(θ) as its eigenfunction [B. C. Low and Y. Q Lou, Astrophys. J. 352, 343 (1990)]. A complete analysis is presented of the eigenvalue spectrum for a given n, providing a unified understanding of the eigenfunctions and the physical relationship between the field's degree of multi-polarity and rate of radial decay via the parameter n. These force-free fields, self-similar on spheres of constant r, have basic astrophysical applications. As explicit solutions they have, over the years, served as standard benchmarks for testing 3D numerical codes developed to compute general force-free fields in the solar corona. The study presented includes a set of illustrative multipolar field solutions to address the magnetohydrodynamics (MHD) issues underlying the observation that the solar corona has a statistical preference for negative and positive magnetic helicities in its northern and southern hemispheres, respectively; a hemispherical effect, unchanging as the Sun's global field reverses polarity in successive eleven-year cycles. Generalizing these force-free fields to the separable form B=(H(θ,φ))/(r{sup n+2}) promises field solutions of even richer topological varieties but allowing for φ-dependence greatly complicates the governing equations that have remained intractable. The axisymmetric results obtained are discussed in relation to this generalization and the Parker Magnetostatic Theorem. The axisymmetric solutions are mathematically related to a family of 3D time-dependent ideal MHD solutions for a polytropic fluid of index γ = 4

Notions of similarity for computational biology models

KAUST Repository

Waltemath, Dagmar

2016-03-21

Computational models used in biology are rapidly increasing in complexity, size, and numbers. To build such large models, researchers need to rely on software tools for model retrieval, model combination, and version control. These tools need to be able to quantify the differences and similarities between computational models. However, depending on the specific application, the notion of similarity may greatly vary. A general notion of model similarity, applicable to various types of models, is still missing. Here, we introduce a general notion of quantitative model similarities, survey the use of existing model comparison methods in model building and management, and discuss potential applications of model comparison. To frame model comparison as a general problem, we describe a theoretical approach to defining and computing similarities based on different model aspects. Potentially relevant aspects of a model comprise its references to biological entities, network structure, mathematical equations and parameters, and dynamic behaviour. Future similarity measures could combine these model aspects in flexible, problem-specific ways in order to mimic users\\' intuition about model similarity, and to support complex model searches in databases.

Notions of similarity for computational biology models

KAUST Repository

Waltemath, Dagmar; Henkel, Ron; Hoehndorf, Robert; Kacprowski, Tim; Knuepfer, Christian; Liebermeister, Wolfram

2016-01-01

Computational models used in biology are rapidly increasing in complexity, size, and numbers. To build such large models, researchers need to rely on software tools for model retrieval, model combination, and version control. These tools need to be able to quantify the differences and similarities between computational models. However, depending on the specific application, the notion of similarity may greatly vary. A general notion of model similarity, applicable to various types of models, is still missing. Here, we introduce a general notion of quantitative model similarities, survey the use of existing model comparison methods in model building and management, and discuss potential applications of model comparison. To frame model comparison as a general problem, we describe a theoretical approach to defining and computing similarities based on different model aspects. Potentially relevant aspects of a model comprise its references to biological entities, network structure, mathematical equations and parameters, and dynamic behaviour. Future similarity measures could combine these model aspects in flexible, problem-specific ways in order to mimic users' intuition about model similarity, and to support complex model searches in databases.

A Novel Hybrid Similarity Calculation Model

Directory of Open Access Journals (Sweden)

Xiaoping Fan

2017-01-01

Full Text Available This paper addresses the problems of similarity calculation in the traditional recommendation algorithms of nearest neighbor collaborative filtering, especially the failure in describing dynamic user preference. Proceeding from the perspective of solving the problem of user interest drift, a new hybrid similarity calculation model is proposed in this paper. This model consists of two parts, on the one hand the model uses the function fitting to describe users’ rating behaviors and their rating preferences, and on the other hand it employs the Random Forest algorithm to take user attribute features into account. Furthermore, the paper combines the two parts to build a new hybrid similarity calculation model for user recommendation. Experimental results show that, for data sets of different size, the model’s prediction precision is higher than the traditional recommendation algorithms.

Link-Based Similarity Measures Using Reachability Vectors

Directory of Open Access Journals (Sweden)

Seok-Ho Yoon

2014-01-01

Full Text Available We present a novel approach for computing link-based similarities among objects accurately by utilizing the link information pertaining to the objects involved. We discuss the problems with previous link-based similarity measures and propose a novel approach for computing link based similarities that does not suffer from these problems. In the proposed approach each target object is represented by a vector. Each element of the vector corresponds to all the objects in the given data, and the value of each element denotes the weight for the corresponding object. As for this weight value, we propose to utilize the probability of reaching from the target object to the specific object, computed using the “Random Walk with Restart” strategy. Then, we define the similarity between two objects as the cosine similarity of the two vectors. In this paper, we provide examples to show that our approach does not suffer from the aforementioned problems. We also evaluate the performance of the proposed methods in comparison with existing link-based measures, qualitatively and quantitatively, with respect to two kinds of data sets, scientific papers and Web documents. Our experimental results indicate that the proposed methods significantly outperform the existing measures.

Similarity search of business process models

NARCIS (Netherlands)

Dumas, M.; García-Bañuelos, L.; Dijkman, R.M.

2009-01-01

Similarity search is a general class of problems in which a given object, called a query object, is compared against a collection of objects in order to retrieve those that most closely resemble the query object. This paper reviews recent work on an instance of this class of problems, where the

A novel numerical framework for self-similarity in plasticity: Wedge indentation in single crystals

Science.gov (United States)

Juul, K. J.; Niordson, C. F.; Nielsen, K. L.; Kysar, J. W.

2018-03-01

A novel numerical framework for analyzing self-similar problems in plasticity is developed and demonstrated. Self-similar problems of this kind include processes such as stationary cracks, void growth, indentation etc. The proposed technique offers a simple and efficient method for handling this class of complex problems by avoiding issues related to traditional Lagrangian procedures. Moreover, the proposed technique allows for focusing the mesh in the region of interest. In the present paper, the technique is exploited to analyze the well-known wedge indentation problem of an elastic-viscoplastic single crystal. However, the framework may be readily adapted to any constitutive law of interest. The main focus herein is the development of the self-similar framework, while the indentation study serves primarily as verification of the technique by comparing to existing numerical and analytical studies. In this study, the three most common metal crystal structures will be investigated, namely the face-centered cubic (FCC), body-centered cubic (BCC), and hexagonal close packed (HCP) crystal structures, where the stress and slip rate fields around the moving contact point singularity are presented.

AD/HD Symptoms and Conduct Problems: Similarities and Differences in Maternal Perceptions

Science.gov (United States)

Maniadaki, Katerina; Sonuga-Barke, Edmund; Kakouros, Efthymios; Karaba, Rania

2006-01-01

Several theories attempt to explain the high co-occurrence of Attention Deficit/ Hyperactivity Disorder (AD/HD) and Conduct Problems (CP). A strong possibility is that AD/HD behaviours lead to the development of CP, due to family coercive interaction patterns, maintained through parental false beliefs regarding child problem behaviour. We compared…

Behavioral/Emotional Problems of Preschoolers

DEFF Research Database (Denmark)

Rescorla, L.A.; Achenbach, T.M.; Ivanova, M.Y.

2012-01-01

This study tested societal effects on caregiver/teacher ratings of behavioral/emotional problems for 10,521 preschoolers from 15 societies. Many societies had problem scale scores within a relatively narrow range, despite differences in language, culture, and other characteristics. The small age...... and gender effects were quite similar across societies. The rank orders of mean item ratings were similar across diverse societies. For 7,380 children from 13 societies, ratings were also obtained from a parent. In all 13 societies, mean Total Problems scores derived from parent ratings were significantly...

A novel numerical framework for self-similarity in plasticity: Wedge indentation in single crystals

DEFF Research Database (Denmark)

Juul, K. J.; Niordson, C. F.; Nielsen, K. L.

2018-01-01

-viscoplastic single crystal. However, the framework may be readily adapted to any constitutive law of interest. The main focus herein is the development of the self-similar framework, while the indentation study serves primarily as verification of the technique by comparing to existing numerical and analytical......A novel numerical framework for analyzing self-similar problems in plasticity is developed and demonstrated. Self-similar problems of this kind include processes such as stationary cracks, void growth, indentation etc. The proposed technique offers a simple and efficient method for handling...

Sound Problems in Interpreting: a Comparative Study of Undergraduate Program at Sebelas Maret State University

Directory of Open Access Journals (Sweden)

Taufik Nur Hidayat

2017-10-01

Full Text Available The study is to classify the problem triggers in consecutive interpreting especially in listening. The objectives of the research are to find out the relationship between listening skills and sound problem by comparing the test results of English student and non-English student and prove that students’ problem triggers are closely related to the writing and reading performances which are caused by listening skill problems such as domain in comprehension, similar word, etc. The method used in the research is descriptive qualitative. The participants are English Department and non English student. Technique of collecting data in the research uses questionnaire, test, and interview. The biggest problem faced by non-English student group is numbering and proper names. It is 34 % which occupy in first rank. Whereas the percentage of English student in comprehension is 27%, then the numbering and proper names, the last is similar word which has 20%. Meanwhile, the test result of English group is 84.5 and non-English group is 60. It represent the background knowledge factors are also play an important role in doing the test. In conclusion, there is relationship between students’ problem triggers, writing and reading performances, especially homophone errors. So, the hypothesis is accepted and it strengthens a currently underdeveloped theory that sounds problem play an important role in listening.

Self-similar factor approximants

International Nuclear Information System (INIS)

Gluzman, S.; Yukalov, V.I.; Sornette, D.

2003-01-01

The problem of reconstructing functions from their asymptotic expansions in powers of a small variable is addressed by deriving an improved type of approximants. The derivation is based on the self-similar approximation theory, which presents the passage from one approximant to another as the motion realized by a dynamical system with the property of group self-similarity. The derived approximants, because of their form, are called self-similar factor approximants. These complement the obtained earlier self-similar exponential approximants and self-similar root approximants. The specific feature of self-similar factor approximants is that their control functions, providing convergence of the computational algorithm, are completely defined from the accuracy-through-order conditions. These approximants contain the Pade approximants as a particular case, and in some limit they can be reduced to the self-similar exponential approximants previously introduced by two of us. It is proved that the self-similar factor approximants are able to reproduce exactly a wide class of functions, which include a variety of nonalgebraic functions. For other functions, not pertaining to this exactly reproducible class, the factor approximants provide very accurate approximations, whose accuracy surpasses significantly that of the most accurate Pade approximants. This is illustrated by a number of examples showing the generality and accuracy of the factor approximants even when conventional techniques meet serious difficulties

Self-similar magnetohydrodynamic boundary layers

Energy Technology Data Exchange (ETDEWEB)

Nunez, Manuel; Lastra, Alberto, E-mail: mnjmhd@am.uva.e [Departamento de Analisis Matematico, Universidad de Valladolid, 47005 Valladolid (Spain)

2010-10-15

The boundary layer created by parallel flow in a magnetized fluid of high conductivity is considered in this paper. Under appropriate boundary conditions, self-similar solutions analogous to the ones studied by Blasius for the hydrodynamic problem may be found. It is proved that for these to be stable, the size of the Alfven velocity at the outer flow must be smaller than the flow velocity, a fact that has a ready physical explanation. The process by which the transverse velocity and the thickness of the layer grow with the size of the Alfven velocity is detailed.

Self-similar magnetohydrodynamic boundary layers

International Nuclear Information System (INIS)

Nunez, Manuel; Lastra, Alberto

2010-01-01

The boundary layer created by parallel flow in a magnetized fluid of high conductivity is considered in this paper. Under appropriate boundary conditions, self-similar solutions analogous to the ones studied by Blasius for the hydrodynamic problem may be found. It is proved that for these to be stable, the size of the Alfven velocity at the outer flow must be smaller than the flow velocity, a fact that has a ready physical explanation. The process by which the transverse velocity and the thickness of the layer grow with the size of the Alfven velocity is detailed.

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.

A Measure of Similarity Between Trajectories of Vessels

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Le QI

2016-03-01

Full Text Available The measurement of similarity between trajectories of vessels is one of the kernel problems that must be addressed to promote the development of maritime intelligent traffic system (ITS. In this study, a new model of trajectory similarity measurement was established to improve the data processing efficiency in dynamic application and to reflect actual sailing behaviors of vessels. In this model, a feature point detection algorithm was proposed to extract feature points, reduce data storage space and save computational resources. A new synthesized distance algorithm was also created to measure the similarity between trajectories by using the extracted feature points. An experiment was conducted to measure the similarity between the real trajectories of vessels. The growth of these trajectories required measurements to be conducted under different voyages. The results show that the similarity measurement between the vessel trajectories is efficient and correct. Comparison of the synthesized distance with the sailing behaviors of vessels proves that results are consistent with actual situations. The experiment results demonstrate the promising application of the proposed model in studying vessel traffic and in supplying reliable data for the development of maritime ITS.

An Internationally Comparative Study of Immigration and Adolescent Emotional and Behavioral Problems:Effects of Generation and Gender

DEFF Research Database (Denmark)

Stevens, Gonneke W J M; Walsh, Sophie D; Huijts, Tim

2015-01-01

psychosomatic symptoms than native adolescents. Effect sizes varied considerable for the different outcomes, and similar effects were found for first- and second-generation immigrant adolescents. Differences in these indicators of emotional and behavioral problems between immigrant and native adolescents did......PURPOSE: Although the potential consequences of immigration for adolescent problem behaviors have been addressed in many former studies, internationally comparative research is scarce. This study investigated the impact of immigration on four indicators of adolescents' emotional and behavioral...... not vary significantly with the receiving country. With two exceptions, effects of immigrant status were similar for boys and girls. Although no differences in psychosomatic symptoms were found between first-generation immigrant and native girls, first-generation immigrant boys reported less psychosomatic...

Size distribution of dust grains: A problem of self-similarity

International Nuclear Information System (INIS)

Henning, TH.; Dorschner, J.; Guertler, J.

1989-01-01

Distribution functions describing the results of natural processes frequently show the shape of power laws. It is an open question whether this behavior is a result simply coming about by the chosen mathematical representation of the observational data or reflects a deep-seated principle of nature. The authors suppose the latter being the case. Using a dust model consisting of silicate and graphite grains Mathis et al. (1977) showed that the interstellar extinction curve can be represented by taking a grain radii distribution of power law type n(a) varies as a(exp -p) with 3.3 less than or equal to p less than or equal to 3.6 (example 1) as a basis. A different approach to understanding power laws like that in example 1 becomes possible by the theory of self-similar processes (scale invariance). The beta model of turbulence (Frisch et al., 1978) leads in an elementary way to the concept of the self-similarity dimension D, a special case of Mandelbrot's (1977) fractal dimension. In the frame of this beta model, it is supposed that on each stage of a cascade the system decays to N clumps and that only the portion beta N remains active further on. An important feature of this model is that the active eddies become less and less space-filling. In the following, the authors assume that grain-grain collisions are such a scale-invarient process and that the remaining grains are the inactive (frozen) clumps of the cascade. In this way, a size distribution n(a) da varies as a(exp -(D+1))da (example 2) results. It seems to be highly probable that the power law character of the size distribution of interstellar dust grains is the result of a self-similarity process. We can, however, not exclude that the process leading to the interstellar grain size distribution is not fragmentation at all

The study on the cephalometric similarity between parents and offspring

Energy Technology Data Exchange (ETDEWEB)

Kang, Woo Ghon; Ahn, Hyung Kyu [Department of Radiology, College of Dentistry, Seoul National University, Seoul (Korea, Republic of)

1975-11-15

The study was performed to investigate cephalometric similarity between parents and offspring of the Korean family by lateral cephalometric analysis. The lateral cephalograms consist of the 8 families comprising 16 parents, 5 sons and 7 daughters. In order to make an investigation of the similarity, 12 measuring points were set up, and 22 linear measurements on each depth, height and 5 angular measurements were made. The author drew up the profilograms to compare parents with offspring in each family group. The obtained results were as follows: 1. There was no common similarity on specific region between parents and offspring in each family group. 2. There was partial similarity between single parent and offspring. 3. The partial similarity between single parent and offspring was noted on the upper face in general.

The study on the cephalometric similarity between parents and offspring

International Nuclear Information System (INIS)

Kang, Woo Ghon; Ahn, Hyung Kyu

1975-01-01

The study was performed to investigate cephalometric similarity between parents and offspring of the Korean family by lateral cephalometric analysis. The lateral cephalograms consist of the 8 families comprising 16 parents, 5 sons and 7 daughters. In order to make an investigation of the similarity, 12 measuring points were set up, and 22 linear measurements on each depth, height and 5 angular measurements were made. The author drew up the profilograms to compare parents with offspring in each family group. The obtained results were as follows: 1. There was no common similarity on specific region between parents and offspring in each family group. 2. There was partial similarity between single parent and offspring. 3. The partial similarity between single parent and offspring was noted on the upper face in general.

Does Solving Insight-Based Problems Differ from Solving Learning-Based Problems? Some Evidence from an ERP Study

Science.gov (United States)

Leikin, Roza; Waisman, Ilana; Leikin, Mark

2016-01-01

We asked: "What are the similarities and differences in mathematical processing associated with solving learning-based and insight-based problems?" To answer this question, the ERP research procedure was employed with 69 male adolescent subjects who solved specially designed insight-based and learning-based tests. Solutions of…

Improved cosine similarity measures of simplified neutrosophic sets for medical diagnoses.

Science.gov (United States)

Ye, Jun

2015-03-01

In pattern recognition and medical diagnosis, similarity measure is an important mathematical tool. To overcome some disadvantages of existing cosine similarity measures of simplified neutrosophic sets (SNSs) in vector space, this paper proposed improved cosine similarity measures of SNSs based on cosine function, including single valued neutrosophic cosine similarity measures and interval neutrosophic cosine similarity measures. Then, weighted cosine similarity measures of SNSs were introduced by taking into account the importance of each element. Further, a medical diagnosis method using the improved cosine similarity measures was proposed to solve medical diagnosis problems with simplified neutrosophic information. The improved cosine similarity measures between SNSs were introduced based on cosine function. Then, we compared the improved cosine similarity measures of SNSs with existing cosine similarity measures of SNSs by numerical examples to demonstrate their effectiveness and rationality for overcoming some shortcomings of existing cosine similarity measures of SNSs in some cases. In the medical diagnosis method, we can find a proper diagnosis by the cosine similarity measures between the symptoms and considered diseases which are represented by SNSs. Then, the medical diagnosis method based on the improved cosine similarity measures was applied to two medical diagnosis problems to show the applications and effectiveness of the proposed method. Two numerical examples all demonstrated that the improved cosine similarity measures of SNSs based on the cosine function can overcome the shortcomings of the existing cosine similarity measures between two vectors in some cases. By two medical diagnoses problems, the medical diagnoses using various similarity measures of SNSs indicated the identical diagnosis results and demonstrated the effectiveness and rationality of the diagnosis method proposed in this paper. The improved cosine measures of SNSs based on cosine

Density-based retrieval from high-similarity image databases

DEFF Research Database (Denmark)

Hansen, Michael Edberg; Carstensen, Jens Michael

2004-01-01

Many image classification problems can fruitfully be thought of as image retrieval in a "high similarity image database" (HSID) characterized by being tuned towards a specific application and having a high degree of visual similarity between entries that should be distinguished. We introduce a me...

Personality and problem gambling: a prospective study of a birth cohort of young adults.

Science.gov (United States)

Slutske, Wendy S; Caspi, Avshalom; Moffitt, Terrie E; Poulton, Richie

2005-07-01

Individual differences in dimensions of personality may play an important role in explaining risk for disordered gambling behavior as well as the comorbidity between disordered gambling behavior and other substance-related addictive disorders. To identify the personality correlates of problem gambling in a representative non-treatment-seeking sample, as well as to determine whether these are similar to the personality correlates of other substance-related addictive disorders and whether individual differences in personality might account for the comorbidity between disordered gambling behavior and other substance-related addictive disorders. Longitudinal population-based study. A complete birth cohort of young adults born in Dunedin, New Zealand, between April 1, 1972, and March 31, 1973 (N = 939; 475 men, 464 women). Multidimensional Personality Questionnaire assessments of personality were obtained at age 18 years; structured interview-based diagnoses of past-year problem gambling and alcohol, cannabis, and nicotine dependence were obtained at age 21 years. Problem gambling at age 21 years was associated with higher scores on the higher-order personality dimension of negative emotionality (d = 0.90) and with lower scores on the personality dimension of constraint (d = -0.72) measured at age 18 years compared with control subjects who did not have a past-year addictive disorder at age 21 years. Problem gambling was also associated with Multidimensional Personality Questionnaire indicators of risk-taking (d = 0.50) and impulsivity (d = 0.56). The personality profile associated with problem gambling was similar to the profiles associated with alcohol, cannabis, and nicotine dependence. The relations between problem gambling and the substance-related addictive disorders (odds ratios = 3.32-3.61) were reduced after controlling for individual differences in personality (odds ratios = 1.90-2.32). From the perspective of personality, problem gambling has much in common

On finding similar items in a stream of transactions

DEFF Research Database (Denmark)

Campagna, Andrea; Pagh, Rasmus

2010-01-01

While there has been a lot of work on finding frequent itemsets in transaction data streams, none of these solve the problem of finding similar pairs according to standard similarity measures. This paper is a first attempt at dealing with this, arguably more important, problem. We start out with ...... in random order, and show that surprisingly, not only is small-space similarity mining possible for the most common similarity measures, but the mining accuracy {\\em improves\\/} with the length of the stream for any fixed support threshold....... with a negative result that also explains the lack of theoretical upper bounds on the space usage of data mining algorithms for finding frequent itemsets: Any algorithm that (even only approximately and with a chance of error) finds the most frequent $k$-itemset must use space $\\Omega...

A Comparison Study on Similarity and Dissimilarity Measures in Clustering Continuous Data.

Directory of Open Access Journals (Sweden)

Ali Seyed Shirkhorshidi

Full Text Available Similarity or distance measures are core components used by distance-based clustering algorithms to cluster similar data points into the same clusters, while dissimilar or distant data points are placed into different clusters. The performance of similarity measures is mostly addressed in two or three-dimensional spaces, beyond which, to the best of our knowledge, there is no empirical study that has revealed the behavior of similarity measures when dealing with high-dimensional datasets. To fill this gap, a technical framework is proposed in this study to analyze, compare and benchmark the influence of different similarity measures on the results of distance-based clustering algorithms. For reproducibility purposes, fifteen publicly available datasets were used for this study, and consequently, future distance measures can be evaluated and compared with the results of the measures discussed in this work. These datasets were classified as low and high-dimensional categories to study the performance of each measure against each category. This research should help the research community to identify suitable distance measures for datasets and also to facilitate a comparison and evaluation of the newly proposed similarity or distance measures with traditional ones.

Mental health problems among conflict-affected adults in Grozny, Chechnya: a qualitative study.

Science.gov (United States)

Nguyen, Amanda J; Feo, Concetta; Idrisov, Kyuri; Pintaldi, Giovanni; Lenglet, Annick; Tsatsaeva, Zalina; Bolton, Paul; Bass, Judith

2016-01-01

A decade of conflict in Chechnya destroyed infrastructure and resulted in widespread exposure to violence. Amidst substantial reconstruction, periodic violence has contributed to an ongoing atmosphere of insecurity. We conducted a qualitative study to understand the mental health and psychosocial problems affecting adult Chechens in this context to inform development of assessment tools for an evaluation study related to individual counseling. Data were collected in July 2014. A convenience sample of 59 Chechen adults was asked to Free List all problems affecting people in the area. Four problems were explored further in 19 Key Interviewee (KI) interviews, with respondents identified using snowball sampling. Data analysis was conducted in Russian by the Chechen interviewers. Multiple mental health and psychosocial problems emerged, including 'bad psychological health', 'depression', 'stress and nervous people', and 'problems in the family'. Aggression, 'emotional blowing', and 'not adequate' behavior were frequently reported indicators of these problems, with negative effects on the whole family. Chechens reported seeking help through informal social networks, psychiatric and psychological services, and Islamic Centers. Chechens reported mental health and psychosocial problems similar to those experienced in other post-conflict settings. The description of 'emotional blowing' mirrored prior findings in Chechen asylum seekers and fits within a cluster of cultural concepts of distress featuring anger that has been identified in other conflict-affected populations. Further exploration of the nature and prevalence of this construct, as well as evaluations of interventions aimed at reducing these symptoms, is warranted.

Self-similarity in applied superconductivity

International Nuclear Information System (INIS)

Dresner, Lawrence

1981-09-01

Self-similarity is a descriptive term applying to a family of curves. It means that the family is invariant to a one-parameter group of affine (stretching) transformations. The property of self-similarity has been exploited in a wide variety of problems in applied superconductivity, namely, (i) transient distribution of the current among the filaments of a superconductor during charge-up, (ii) steady distribution of current among the filaments of a superconductor near the current leads, (iii) transient heat transfer in superfluid helium, (iv) transient diffusion in cylindrical geometry (important in studying the growth rate of the reacted layer in A15 materials), (v) thermal expulsion of helium from quenching cable-in-conduit conductors, (vi) eddy current heating of irregular plates by slow, ramped fields, and (vii) the specific heat of type-II superconductors. Most, but not all, of the applications involve differential equations, both ordinary and partial. The novel methods explained in this report should prove of great value in other fields, just as they already have done in applied superconductivity. (author)

The Chicken Problem.

Science.gov (United States)

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)

Attention problems in very preterm children from childhood to adulthood: the Bavarian Longitudinal Study.

Science.gov (United States)

Breeman, Linda D; Jaekel, Julia; Baumann, Nicole; Bartmann, Peter; Wolke, Dieter

2016-02-01

Very preterm (VP; gestational age attention problems in childhood and adulthood. The stability of these problems into adulthood is not known. The Bavarian Longitudinal Study is a prospective cohort study that followed 260 VP/VLBW and 229 term-born individuals from birth to adulthood. Data on attention were collected at 6, 8, and 26 years of age, using parent reports, expert behavior observations, and clinical ADHD diagnoses. At each assessment, VP/VLBW individuals had significantly more attention problems, shorter attention span, and were more frequently diagnosed with ADHD than term-born comparisons. In both VP/VLBW and term-born individuals, overall, attention span increased and attention problems decreased from childhood to adulthood. Attention problems and attention span were more stable over time for VP/VLBW than term-born individuals. Similarly, ADHD diagnoses showed moderate stability from childhood to adulthood in VP/VLBW, but not in term-born individuals. However, when those with severe disabilities were excluded, differences between VP/VLBW and term-born individuals reduced. Despite improvement in attention regulation from childhood to adulthood, children born very preterm remained at increased risk for attention problems in adulthood. In contrast, term-born children with clinical attention problems outgrew these by adulthood. As inattentive behavior of VP/VLBW children may be overlooked by teachers, it may be necessary to raise awareness for school intervention programs that reduce attention problems in VP/VLBW children. © 2015 Association for Child and Adolescent Mental Health.

Response problems in a vacation panel study

Science.gov (United States)

Christine A. Vogt; Susan I. Stewart

2001-01-01

This paper investigates response problems encountered in a panel study of travel behavior. Though the overall response rate to the three-wave panel study was acceptable (over 60%), three types of response problems were encountered: refusal, non-response, and attrition. In a follow-up phone survey, a sample of individuals from each problem response group was questioned...

Atopic conditions and mental health problems: a 3-year follow-up study.

Science.gov (United States)

Lien, Lars; Green, Kristian; Thoresen, Magne; Bjertness, Espen

2010-09-01

The aim of this study was to test the hypothesis that atopic conditions at 15/16 years of age affect both internalized and externalized mental health problems 3 years later. Combined school and postal survey was conducted in urban and rural settings. A total of 3,674 adolescents (70.1% response rate) were followed at two time points and interviewed with similar questionnaires at baseline and follow-up. Hopkins Symptoms Checklist (HSCL-10) was used to assess internalized problems, and two subscales (conduct problems and hyperactivity) from the Strength and Difficulties Questionnaire to measure externalized mental health problems. The atopic conditions investigated were asthma, hay fever and eczema by asking the adolescents whether these conditions were present or not. There was an increase in the prevalence of internalized mental health problems from about 17-25% and a decrease in externalized mental health problems and number of atopic conditions in the follow-up period. Of the atopic conditions, hay fever was most prevalent with about 34% at 15 years of age and 20% at 18. The asthma prevalence was at 10 and 5% and eczema at 25 and 10%, respectively. Internalized mental health problems among girls were significantly associated with atopic conditions 3 years earlier, also after controlling for confounding variables. To live with atopic conditions seem to affect the mood and level of anxiety among adolescent girls. This should be kept in mind by health professionals treating young girls with atopic conditions.

Multicriteria decision-making method based on a cosine similarity ...

African Journals Online (AJOL)

the cosine similarity measure is often used in information retrieval, citation analysis, and automatic classification. However, it scarcely deals with trapezoidal fuzzy information and multicriteria decision-making problems. For this purpose, a cosine similarity measure between trapezoidal fuzzy numbers is proposed based on ...

How Are Traits Related to Problem Behavior in Preschoolers? Similarities and Contrasts between Temperament and Personality

Science.gov (United States)

De Pauw, Sarah S. W.; Mervielde, Ivan; Van Leeuwen, Karla G.

2009-01-01

The lack of empirical research relating temperament models and personality hinders conceptual integration and holds back research linking childhood traits to problem behavior or maladjustment. This study evaluates, within a sample of 443 preschoolers, the relationships between children's maladaptation and traits measured by three temperament…

Common Group Problems: A Field Study.

Science.gov (United States)

Weinberg, Sanford B.; And Others

1981-01-01

A field study of a naturally functioning group (N=125) was conducted to identify common group problems. Trained observers attended group meetings and described the problems encountered. Difficulties of cohesion, leadership, sub-group formation, and personality conflict were identified. (RC)

A Survey of Binary Similarity and Distance Measures

Directory of Open Access Journals (Sweden)

Seung-Seok Choi

2010-02-01

Full Text Available The binary feature vector is one of the most common representations of patterns and measuring similarity and distance measures play a critical role in many problems such as clustering, classification, etc. Ever since Jaccard proposed a similarity measure to classify ecological species in 1901, numerous binary similarity and distance measures have been proposed in various fields. Applying appropriate measures results in more accurate data analysis. Notwithstanding, few comprehensive surveys on binary measures have been conducted. Hence we collected 76 binary similarity and distance measures used over the last century and reveal their correlations through the hierarchical clustering technique.

Self-Similar Spin Images for Point Cloud Matching

Science.gov (United States)

Pulido, Daniel

based on the concept of self-similarity to aid in the scale and feature matching steps. An open problem in fusion is how best to extract features from two point clouds and then perform feature-based matching. The proposed approach for this matching step is the use of local self-similarity as an invariant measure to match features. In particular, the proposed approach is to combine the concept of local self-similarity with a well-known feature descriptor, Spin Images, and thereby define "Self-Similar Spin Images". This approach is then extended to the case of matching two points clouds in very different coordinate systems (e.g., a geo-referenced Lidar point cloud and stereo-image derived point cloud without geo-referencing). The use of Self-Similar Spin Images is again applied to address this problem by introducing a "Self-Similar Keyscale" that matches the spatial scales of two point clouds. Another open problem is how best to detect changes in content between two point clouds. A method is proposed to find changes between two point clouds by analyzing the order statistics of the nearest neighbors between the two clouds, and thereby define the "Nearest Neighbor Order Statistic" method. Note that the well-known Hausdorff distance is a special case as being just the maximum order statistic. Therefore, by studying the entire histogram of these nearest neighbors it is expected to yield a more robust method to detect points that are present in one cloud but not the other. This approach is applied at multiple resolutions. Therefore, changes detected at the coarsest level will yield large missing targets and at finer levels will yield smaller targets.

Experimental Study of Dowel Bar Alternatives Based on Similarity Model Test

Directory of Open Access Journals (Sweden)

Chichun Hu

2017-01-01

Full Text Available In this study, a small-scaled accelerated loading test based on similarity theory and Accelerated Pavement Analyzer was developed to evaluate dowel bars with different materials and cross-sections. Jointed concrete specimen consisting of one dowel was designed as scaled model for the test, and each specimen was subjected to 864 thousand loading cycles. Deflections between jointed slabs were measured with dial indicators, and strains of the dowel bars were monitored with strain gauges. The load transfer efficiency, differential deflection, and dowel-concrete bearing stress for each case were calculated from these measurements. The test results indicated that the effect of the dowel modulus on load transfer efficiency can be characterized based on the similarity model test developed in the study. Moreover, round steel dowel was found to have similar performance to larger FRP dowel, and elliptical dowel can be preferentially considered in practice.

Predictive modeling of human perception subjectivity: feasibility study of mammographic lesion similarity

Science.gov (United States)

Xu, Songhua; Hudson, Kathleen; Bradley, Yong; Daley, Brian J.; Frederick-Dyer, Katherine; Tourassi, Georgia

2012-02-01

The majority of clinical content-based image retrieval (CBIR) studies disregard human perception subjectivity, aiming to duplicate the consensus expert assessment of the visual similarity on example cases. The purpose of our study is twofold: i) discern better the extent of human perception subjectivity when assessing the visual similarity of two images with similar semantic content, and (ii) explore the feasibility of personalized predictive modeling of visual similarity. We conducted a human observer study in which five observers of various expertise were shown ninety-nine triplets of mammographic masses with similar BI-RADS descriptors and were asked to select the two masses with the highest visual relevance. Pairwise agreement ranged between poor and fair among the five observers, as assessed by the kappa statistic. The observers' self-consistency rate was remarkably low, based on repeated questions where either the orientation or the presentation order of a mass was changed. Various machine learning algorithms were explored to determine whether they can predict each observer's personalized selection using textural features. Many algorithms performed with accuracy that exceeded each observer's self-consistency rate, as determined using a cross-validation scheme. This accuracy was statistically significantly higher than would be expected by chance alone (two-tailed p-value ranged between 0.001 and 0.01 for all five personalized models). The study confirmed that human perception subjectivity should be taken into account when developing CBIR-based medical applications.

Everyday problem solving in African Americans and European Americans with Alzheimer's disease: an exploratory study.

Science.gov (United States)

Ripich, Danielle N; Fritsch, Thomas; Ziol, Elaine

2002-03-01

In this exploratory study, we compared the performance of 10 African American and 26 European American persons with early- to mid-stage Alzheimer's disease (AD) to 20 nondemented elderly (NE), using a shortened version of the Test of Problem Solving (TOPS). The TOPS measures verbal reasoning to solve everyday problems in five areas: explaining inferences, determining causes, answering negative why questions, determining solutions, and avoiding problems. Six linguistic measures were also examined: total utterances, abandoned utterances, length of utterances, maze words, questions, and total words. NE performed better than AD subjects on all but one measure of verbal reasoning ability. AD subjects also showed a trend to use more total utterances and abandoned utterances than NE. For the AD group, no ethnic differences were found for verbal reasoning or linguistic measures. The findings from this preliminary investigation suggest that, compared to European Americans, African American persons with AD demonstrate similar everyday problem solving and linguistic skills. Thus, assessments such as TOPS that examine everyday problem solving may be a useful nonbiased evaluation tool for persons with AD in these two ethnic groups.

Numerical study of similarity in prototype and model pumped turbines

International Nuclear Information System (INIS)

Li, Z J; Wang, Z W; Bi, H L

2014-01-01

Similarity study of prototype and model pumped turbines are performed by numerical simulation and the partial discharge case is analysed in detail. It is found out that in the RSI (rotor-stator interaction) region where the flow is convectively accelerated with minor flow separation, a high level of similarity in flow patterns and pressure fluctuation appear with relative pressure fluctuation amplitude of model turbine slightly higher than that of prototype turbine. As for the condition in the runner where the flow is convectively accelerated with severe separation, similarity fades substantially due to different topology of flow separation and vortex formation brought by distinctive Reynolds numbers of the two turbines. In the draft tube where the flow is diffusively decelerated, similarity becomes debilitated owing to different vortex rope formation impacted by Reynolds number. It is noted that the pressure fluctuation amplitude and characteristic frequency of model turbine are larger than those of prototype turbine. The differences in pressure fluctuation characteristics are discussed theoretically through dimensionless Navier-Stokes equation. The above conclusions are all made based on simulation without regard to the penstock response and resonance

Peer influences on internalizing and externalizing problems among adolescents: a longitudinal social network analysis.

Science.gov (United States)

Fortuin, Janna; van Geel, Mitch; Vedder, Paul

2015-04-01

Adolescents who like each other may become more similar to each other with regard to internalizing and externalizing problems, though it is not yet clear which social mechanisms explain these similarities. In this longitudinal study, we analyzed four mechanisms that may explain similarity in adolescent peer networks with regard to externalizing and internalizing problems: selection, socialization, avoidance and withdrawal. At three moments during one school-year, we asked 542 adolescents (8th grade, M-age = 13.3 years, 51 % female) to report who they liked in their classroom, and their own internalizing and externalizing problems. Adolescents tend to prefer peers who have similar externalizing problem scores, but no significant selection effect was found for internalizing problems. Adolescents who share the same group of friends socialize each other and then become more similar with respect to externalizing problems, but not with respect to internalizing problems. We found no significant effects for avoidance or withdrawal. Adolescents may choose to belong to a peer group that is similar to them in terms of externalizing problem behaviors, and through peer group socialization (e.g., enticing, modelling, mimicking, and peer pressure) become more similar to that group over time.

Scaling Relations and Self-Similarity of 3-Dimensional Reynolds-Averaged Navier-Stokes Equations.

Science.gov (United States)

Ercan, Ali; Kavvas, M Levent

2017-07-25

Scaling conditions to achieve self-similar solutions of 3-Dimensional (3D) Reynolds-Averaged Navier-Stokes Equations, as an initial and boundary value problem, are obtained by utilizing Lie Group of Point Scaling Transformations. By means of an open-source Navier-Stokes solver and the derived self-similarity conditions, we demonstrated self-similarity within the time variation of flow dynamics for a rigid-lid cavity problem under both up-scaled and down-scaled domains. The strength of the proposed approach lies in its ability to consider the underlying flow dynamics through not only from the governing equations under consideration but also from the initial and boundary conditions, hence allowing to obtain perfect self-similarity in different time and space scales. The proposed methodology can be a valuable tool in obtaining self-similar flow dynamics under preferred level of detail, which can be represented by initial and boundary value problems under specific assumptions.

Similarity Solutions for Multiterm Time-Fractional Diffusion Equation

OpenAIRE

Elsaid, A.; Abdel Latif, M. S.; Maneea, M.

2016-01-01

Similarity method is employed to solve multiterm time-fractional diffusion equation. The orders of the fractional derivatives belong to the interval (0,1] and are defined in the Caputo sense. We illustrate how the problem is reduced from a multiterm two-variable fractional partial differential equation to a multiterm ordinary fractional differential equation. Power series solution is obtained for the resulting ordinary problem and the convergence of the series solution is discussed. Based on ...

Research Projects in Physics: A Mechanism for Teaching Ill-Structured Problem Solving

Science.gov (United States)

Milbourne, Jeff; Bennett, Jonathan

2017-10-01

Physics education research has a tradition of studying problem solving, exploring themes such as physical intuition and differences between expert and novice problem solvers. However, most of this work has focused on traditional, or well-structured, problems, similar to what might appear in a textbook. Less work has been done with open-ended, or ill-structured, problems, similar to the types of problems students might face in their professional lives. Given the national discourse on educational system reform aligned with 21st century skills, including problem solving, it is critical to provide educational experiences that help students learn to solve all types of problems, including ill-structured problems.

Several problems in accelerator shielding study

International Nuclear Information System (INIS)

Nakamura, Takashi; Hirayama, Hideo; Ban, Shuichi.

1980-01-01

Recently, the utilization of accelerators has increased rapidly, and the increase of accelerating energy and beam intensity is also remarkable. The studies on accelerator shielding have become important, because the amount of radiation emitted from accelerators increased, the regulation of the dose of environmental radiation was tightened, and the cost of constructing shielding rose. As the plans of constructing large accelerators have been made successively, the survey on the present state and the problems of the studies on accelerator shielding was carried out. Accelerators are classified into electron accelerators and proton accelerators in view of the studies on shielding. In order to start the studies on accelerator shielding, first, the preparation of the cross section data is indispensable. The cross sections for generating Bremsstrahlung, photonuclear reactions generating neutrons, generation of neutrons by hadrons, nuclear reaction of neutrons and generation of gamma-ray by hadrons are described. The generation of neutrons and gamma-ray as the problems of thick targets is explained. The shielding problems are complex and diversified, but in this paper, the studies on the shielding, by which basic data are obtainable, are taken up, such as beam damping and side wall shielding. As for residual radioactivity, main nuclides and the difference of residual radioactivity according to substances have been studied. (J.P.N.)

A Unified Model of Attention and Problem Solving.

Science.gov (United States)

1984-02-01

paradigma deocribed boro. In confliot condition. In a facolitation condition GREEN Stroup sitnations signls are preented simultaneously o would be plinted In...and perforlao. paradigma similar to theae studied .. . .. ’ Attention and Problem solInS Page 65 Attention and Problem Solving Page 66 her.. Mis

A COMPARISON OF SEMANTIC SIMILARITY MODELS IN EVALUATING CONCEPT SIMILARITY

Directory of Open Access Journals (Sweden)

Q. X. Xu

2012-08-01

Full Text Available The semantic similarities are important in concept definition, recognition, categorization, interpretation, and integration. Many semantic similarity models have been established to evaluate semantic similarities of objects or/and concepts. To find out the suitability and performance of different models in evaluating concept similarities, we make a comparison of four main types of models in this paper: the geometric model, the feature model, the network model, and the transformational model. Fundamental principles and main characteristics of these models are introduced and compared firstly. Land use and land cover concepts of NLCD92 are employed as examples in the case study. The results demonstrate that correlations between these models are very high for a possible reason that all these models are designed to simulate the similarity judgement of human mind.

Using a general problem-solving strategy to promote transfer.

Science.gov (United States)

Youssef-Shalala, Amina; Ayres, Paul; Schubert, Carina; Sweller, John

2014-09-01

Cognitive load theory was used to hypothesize that a general problem-solving strategy based on a make-as-many-moves-as-possible heuristic could facilitate problem solutions for transfer problems. In four experiments, school students were required to learn about a topic through practice with a general problem-solving strategy, through a conventional problem solving strategy or by studying worked examples. In Experiments 1 and 2 using junior high school students learning geometry, low knowledge students in the general problem-solving group scored significantly higher on near or far transfer tests than the conventional problem-solving group. In Experiment 3, an advantage for a general problem-solving group over a group presented worked examples was obtained on far transfer tests using the same curriculum materials, again presented to junior high school students. No differences between conditions were found in Experiments 1, 2, or 3 using test problems similar to the acquisition problems. Experiment 4 used senior high school students studying economics and found the general problem-solving group scored significantly higher than the conventional problem-solving group on both similar and transfer tests. It was concluded that the general problem-solving strategy was helpful for novices, but not for students that had access to domain-specific knowledge. PsycINFO Database Record (c) 2014 APA, all rights reserved.

Inter Genre Similarity Modelling For Automatic Music Genre Classification

OpenAIRE

Bagci, Ulas; Erzin, Engin

2009-01-01

Music genre classification is an essential tool for music information retrieval systems and it has been finding critical applications in various media platforms. Two important problems of the automatic music genre classification are feature extraction and classifier design. This paper investigates inter-genre similarity modelling (IGS) to improve the performance of automatic music genre classification. Inter-genre similarity information is extracted over the mis-classified feature population....

A population-based study of gastroesophageal reflux disease and sleep problems in elderly twins.

Directory of Open Access Journals (Sweden)

Anna Lindam

Full Text Available BACKGROUND & AIMS: Previous studies indicate an association between sleep problems and gastroesophageal reflux disease (GERD. Although both these conditions separately have moderate heritabilities, confounding by genetic factors has not previously been taken into account. This study aimed to reveal the association between sleep problems and GERD, while adjusting for heredity and other potential confounding factors. METHODS: This cross-sectional population-based study included all 8,014 same-sexed twins of at least 65 years of age and born in Sweden between 1886 and 1958, who participated in telephone interviews in 1998-2002. Three logistic regression models were used 1 external control analysis, 2 within-pair co-twin analysis with dizygotic (DZ twin pairs discordant for GERD, and 3 within-pair co-twin analysis with monozygotic (MZ twin pairs discordant for GERD. Odds ratios (ORs with 95% confidence intervals (CIs were calculated and adjusted for established risk factors for GERD, i.e. sex, age, body mass index (BMI, tobacco smoking, and educational level. RESULTS: A dose-response association was identified between increasing levels of sleep problems and GERD in the external control analysis. Individuals who often experienced sleep problems had a two-fold increased occurrence of GERD compared to those who seldom had sleep problems (OR 2.0, 95% CI 1.8-2.4. The corresponding association was of similar strength in the co-twin analysis including 356 DZ pairs (OR 2.2, 95% CI 1.6-3.4, and in the co-twin analysis including 210 MZ pairs (OR 1.5, 95% CI 0.9-2.7. CONCLUSION: A dose-dependent association between sleep problems and GERD remains after taking heredity and other known risk factors for GERD into account.

The empirical versus DSM-oriented approach of the child behavior checklist: Similarities and dissimilarities

NARCIS (Netherlands)

Wolff, M.S. de; Vogels, A.G.C.; Reijneveld, S.A.

2014-01-01

The DSM-oriented approach of the Child Behavior Checklist (CBCL) is a relatively new classification of problem behavior in children and adolescents. Given the clinical and scientific relevance of the CBCL, this study examines similarities and dissimilarities between the empirical and the

The Empirical Versus DSM-Oriented Approach of the Child Behavior Checklist Similarities and Dissimilarities

NARCIS (Netherlands)

de Wolff, Marianne S.; Vogels, Anton G. C.; Reijneveld, Sijmen A.

2014-01-01

The DSM-oriented approach of the Child Behavior Checklist (CBCL) is a relatively new classification of problem behavior in children and adolescents. Given the clinical and scientific relevance of the CBCL, this study examines similarities and dissimilarities between the empirical and the

Solved problems in electromagnetics

CERN Document Server

Salazar Bloise, Félix; Bayón Rojo, Ana; Gascón Latasa, Francisco

2017-01-01

This book presents the fundamental concepts of electromagnetism through problems with a brief theoretical introduction at the beginning of each chapter. The present book has a strong  didactic character. It explains all the mathematical steps and the theoretical concepts connected with the development of the problem. It guides the reader to understand the employed procedures to learn to solve the exercises independently. The exercises are structured in a similar way: The chapters begin with easy problems increasing progressively in the level of difficulty. This book is written for students of physics and engineering in the framework of the new European Plans of Study for Bachelor and Master and also for tutors and lecturers. .

On Prolonging Network Lifetime through Load-Similar Node Deployment in Wireless Sensor Networks

Science.gov (United States)

Li, Qiao-Qin; Gong, Haigang; Liu, Ming; Yang, Mei; Zheng, Jun

2011-01-01

This paper is focused on the study of the energy hole problem in the Progressive Multi-hop Rotational Clustered (PMRC)-structure, a highly scalable wireless sensor network (WSN) architecture. Based on an analysis on the traffic load distribution in PMRC-based WSNs, we propose a novel load-similar node distribution strategy combined with the Minimum Overlapping Layers (MOL) scheme to address the energy hole problem in PMRC-based WSNs. In this strategy, sensor nodes are deployed in the network area according to the load distribution. That is, more nodes shall be deployed in the range where the average load is higher, and then the loads among different areas in the sensor network tend to be balanced. Simulation results demonstrate that the load-similar node distribution strategy prolongs network lifetime and reduces the average packet latency in comparison with existing nonuniform node distribution and uniform node distribution strategies. Note that, besides the PMRC structure, the analysis model and the proposed load-similar node distribution strategy are also applicable to other multi-hop WSN structures. PMID:22163809

Emotional energy, work self-efficacy, and perceived similarity during the Mars 520 study.

Science.gov (United States)

Solcová, Iva; Gushin, Vadim; Vinokhodova, Alla; Lukavský, Jirí

2013-11-01

The objective of the present research was to study the dynamics of changes in emotional energy, work self-efficacy and perceived similarity in the crew of the Mars 520 experimental study. The study comprised six volunteers, all men, between 27-38 yr of age (M = 32.16; SD = 4.99). The Mars 520 experimental study simulated all the elements of the proposed Mars mission that could be ground simulated, i.e., traveling to Mars, orbiting it, landing, and returning to Earth. During the simulation, measures of emotional energy, work self-efficacy, and perceived similarity were repeated every month. The data were analyzed using linear mixed effect models. Emotional energy, work self-efficacy, and perceived similarity gradually increased in the course of the simulation. There was no evidence for a so-called third quarter phenomenon (the most strenuous period of group isolation, psychologically, emotionally, and socially) in our data. On the contrary, work self-efficacy, emotional energy, and group cohesion (indexed here by the subject's perceived similarity to others) increased significantly in the course of the simulation, with the latter two variables showing positive growth in the group functioning.

A voxel-based morphometry study comparing problem gamblers, alcohol abusers, and healthy controls

NARCIS (Netherlands)

van Holst, R.J.; de Ruiter, M.B.; van den Brink, W.; Veltman, D.J.; Goudriaan, A.E.

2012-01-01

Background: Alcohol use disorders (AUDs) are associated with smaller grey matter volumes in cortical and subcortical brain regions which are related to cognitive impairments often found in these disorders. Similar cognitive impairments have been found in patients suffering from problem gambling

Multidimensional Riemann problem with self-similar internal structure - part III - a multidimensional analogue of the HLLI Riemann solver for conservative hyperbolic systems

Science.gov (United States)

Balsara, Dinshaw S.; Nkonga, Boniface

2017-10-01

Just as the quality of a one-dimensional approximate Riemann solver is improved by the inclusion of internal sub-structure, the quality of a multidimensional Riemann solver is also similarly improved. Such multidimensional Riemann problems arise when multiple states come together at the vertex of a mesh. The interaction of the resulting one-dimensional Riemann problems gives rise to a strongly-interacting state. We wish to endow this strongly-interacting state with physically-motivated sub-structure. The fastest way of endowing such sub-structure consists of making a multidimensional extension of the HLLI Riemann solver for hyperbolic conservation laws. Presenting such a multidimensional analogue of the HLLI Riemann solver with linear sub-structure for use on structured meshes is the goal of this work. The multidimensional MuSIC Riemann solver documented here is universal in the sense that it can be applied to any hyperbolic conservation law. The multidimensional Riemann solver is made to be consistent with constraints that emerge naturally from the Galerkin projection of the self-similar states within the wave model. When the full eigenstructure in both directions is used in the present Riemann solver, it becomes a complete Riemann solver in a multidimensional sense. I.e., all the intermediate waves are represented in the multidimensional wave model. The work also presents, for the very first time, an important analysis of the dissipation characteristics of multidimensional Riemann solvers. The present Riemann solver results in the most efficient implementation of a multidimensional Riemann solver with sub-structure. Because it preserves stationary linearly degenerate waves, it might also help with well-balancing. Implementation-related details are presented in pointwise fashion for the one-dimensional HLLI Riemann solver as well as the multidimensional MuSIC Riemann solver.

Television and video game exposure and the development of attention problems.

Science.gov (United States)

Swing, Edward L; Gentile, Douglas A; Anderson, Craig A; Walsh, David A

2010-08-01

Television viewing has been associated with greater subsequent attention problems in children. Few studies have examined the possibility of a similar association between video games and attention problems, and none of these has used a longitudinal design. A sample of 1323 middle childhood participants were assessed during a 13-month period by parent- and child-reported television and video game exposure as well as teacher-reported attention problems. Another sample of 210 late adolescent/early adult participants provided self-reports of television exposure, video game exposure, and attention problems. Exposure to television and video games was associated with greater attention problems. The association of television and video games to attention problems in the middle childhood sample remained significant when earlier attention problems and gender were statistically controlled. The associations of screen media and attention problems were similar across media type (television or video games) and age (middle childhood or late adolescent/early adult). Viewing television and playing video games each are associated with increased subsequent attention problems in childhood. It seems that a similar association among television, video games, and attention problems exists in late adolescence and early adulthood. Research on potential risk factors for attention problems should be expanded to include video games in addition to television.

Similarity Solutions for Multiterm Time-Fractional Diffusion Equation

Directory of Open Access Journals (Sweden)

A. Elsaid

2016-01-01

Full Text Available Similarity method is employed to solve multiterm time-fractional diffusion equation. The orders of the fractional derivatives belong to the interval (0,1] and are defined in the Caputo sense. We illustrate how the problem is reduced from a multiterm two-variable fractional partial differential equation to a multiterm ordinary fractional differential equation. Power series solution is obtained for the resulting ordinary problem and the convergence of the series solution is discussed. Based on the obtained results, we propose a definition for a multiterm error function with generalized coefficients.

A Microgenetic Study of Insightful Problem Solving

Science.gov (United States)

Luwel, Koen; Siegler, Robert S.; Verschaffel, Lieven

2008-01-01

An eight-session microgenetic study of acquisition of an insightful problem-solving strategy was conducted. A total of 35 second graders who did not use this insightful strategy initially were assigned to two groups that differed in the frequency of problems likely to facilitate discovery and generalization of the strategy. Children in the…

A space-efficient algorithm for local similarities.

Science.gov (United States)

Huang, X Q; Hardison, R C; Miller, W

1990-10-01

Existing dynamic-programming algorithms for identifying similar regions of two sequences require time and space proportional to the product of the sequence lengths. Often this space requirement is more limiting than the time requirement. We describe a dynamic-programming local-similarity algorithm that needs only space proportional to the sum of the sequence lengths. The method can also find repeats within a single long sequence. To illustrate the algorithm's potential, we discuss comparison of a 73,360 nucleotide sequence containing the human beta-like globin gene cluster and a corresponding 44,594 nucleotide sequence for rabbit, a problem well beyond the capabilities of other dynamic-programming software.

Determination of subjective similarity for pairs of masses and pairs of clustered microcalcifications on mammograms: Comparison of similarity ranking scores and absolute similarity ratings

International Nuclear Information System (INIS)

Muramatsu, Chisako; Li Qiang; Schmidt, Robert A.; Shiraishi, Junji; Suzuki, Kenji; Newstead, Gillian M.; Doi, Kunio

2007-01-01

The presentation of images that are similar to that of an unknown lesion seen on a mammogram may be helpful for radiologists to correctly diagnose that lesion. For similar images to be useful, they must be quite similar from the radiologists' point of view. We have been trying to quantify the radiologists' impression of similarity for pairs of lesions and to establish a ''gold standard'' for development and evaluation of a computerized scheme for selecting such similar images. However, it is considered difficult to reliably and accurately determine similarity ratings, because they are subjective. In this study, we compared the subjective similarities obtained by two different methods, an absolute rating method and a 2-alternative forced-choice (2AFC) method, to demonstrate that reliable similarity ratings can be determined by the responses of a group of radiologists. The absolute similarity ratings were previously obtained for pairs of masses and pairs of microcalcifications from five and nine radiologists, respectively. In this study, similarity ranking scores for eight pairs of masses and eight pairs of microcalcifications were determined by use of the 2AFC method. In the first session, the eight pairs of masses and eight pairs of microcalcifications were grouped and compared separately for determining the similarity ranking scores. In the second session, another similarity ranking score was determined by use of mixed pairs, i.e., by comparison of the similarity of a mass pair with that of a calcification pair. Four pairs of masses and four pairs of microcalcifications were grouped together to create two sets of eight pairs. The average absolute similarity ratings and the average similarity ranking scores showed very good correlations in the first study (Pearson's correlation coefficients: 0.94 and 0.98 for masses and microcalcifications, respectively). Moreover, in the second study, the correlations between the absolute ratings and the ranking scores were also

Spectral Classification of Similar Materials using the Tetracorder Algorithm: The Calcite-Epidote-Chlorite Problem

Science.gov (United States)

Dalton, J. Brad; Bove, Dana; Mladinich, Carol; Clark, Roger; Rockwell, Barnaby; Swayze, Gregg; King, Trude; Church, Stanley

2001-01-01

Recent work on automated spectral classification algorithms has sought to distinguish ever-more similar materials. From modest beginnings separating shade, soil, rock and vegetation to ambitious attempts to discriminate mineral types and specific plant species, the trend seems to be toward using increasingly subtle spectral differences to perform the classification. Rule-based expert systems exploiting the underlying physics of spectroscopy such as the US Geological Society Tetracorder system are now taking advantage of the high spectral resolution and dimensionality of current imaging spectrometer designs to discriminate spectrally similar materials. The current paper details recent efforts to discriminate three minerals having absorptions centered at the same wavelength, with encouraging results.

Extending the Similarity-Attraction Effect : The effects of When-Similarity in mediated communication

NARCIS (Netherlands)

Kaptein, M.C.; Castaneda, D.; Fernandez, N.; Nass, C.

2014-01-01

The feeling of connectedness experienced in computer-mediated relationships can be explained by the similarity-attraction effect (SAE). Though SAE is well established in psychology, the effects of some types of similarity have not yet been explored. In 2 studies, we demonstrate similarity-attraction

The Application of Similar Image Retrieval in Electronic Commerce

Science.gov (United States)

Hu, YuPing; Yin, Hua; Han, Dezhi; Yu, Fei

2014-01-01

Traditional online shopping platform (OSP), which searches product information by keywords, faces three problems: indirect search mode, large search space, and inaccuracy in search results. For solving these problems, we discuss and research the application of similar image retrieval in electronic commerce. Aiming at improving the network customers' experience and providing merchants with the accuracy of advertising, we design a reasonable and extensive electronic commerce application system, which includes three subsystems: image search display subsystem, image search subsystem, and product information collecting subsystem. This system can provide seamless connection between information platform and OSP, on which consumers can automatically and directly search similar images according to the pictures from information platform. At the same time, it can be used to provide accuracy of internet marketing for enterprises. The experiment shows the efficiency of constructing the system. PMID:24883411

The Application of Similar Image Retrieval in Electronic Commerce

Directory of Open Access Journals (Sweden)

YuPing Hu

2014-01-01

Full Text Available Traditional online shopping platform (OSP, which searches product information by keywords, faces three problems: indirect search mode, large search space, and inaccuracy in search results. For solving these problems, we discuss and research the application of similar image retrieval in electronic commerce. Aiming at improving the network customers’ experience and providing merchants with the accuracy of advertising, we design a reasonable and extensive electronic commerce application system, which includes three subsystems: image search display subsystem, image search subsystem, and product information collecting subsystem. This system can provide seamless connection between information platform and OSP, on which consumers can automatically and directly search similar images according to the pictures from information platform. At the same time, it can be used to provide accuracy of internet marketing for enterprises. The experiment shows the efficiency of constructing the system.

The application of similar image retrieval in electronic commerce.

Science.gov (United States)

Hu, YuPing; Yin, Hua; Han, Dezhi; Yu, Fei

2014-01-01

Traditional online shopping platform (OSP), which searches product information by keywords, faces three problems: indirect search mode, large search space, and inaccuracy in search results. For solving these problems, we discuss and research the application of similar image retrieval in electronic commerce. Aiming at improving the network customers' experience and providing merchants with the accuracy of advertising, we design a reasonable and extensive electronic commerce application system, which includes three subsystems: image search display subsystem, image search subsystem, and product information collecting subsystem. This system can provide seamless connection between information platform and OSP, on which consumers can automatically and directly search similar images according to the pictures from information platform. At the same time, it can be used to provide accuracy of internet marketing for enterprises. The experiment shows the efficiency of constructing the system.

How can professionals carry out recognition towards children of parents with alcohol problems? A qualitative interview study.

Science.gov (United States)

Werner, Anne; Malterud, Kirsti

2017-02-01

The aim of this study was to explore informal adult support experienced by children with parental alcohol problems to understand how professionals can show recognition in a similar way. We conducted a qualitative interview study with retrospective accounts from nine adults growing up with problem-drinking parents. Data were analysed with systematic text condensation. Goffman's concept "frame" offered a lens to study how supportive situations were defined and to understand opportunities and limitations for translation of recognition acts and attitudes to professional contexts. Analysis demonstrated frames of commonplace interaction where children experienced that adults recognised and responded to their needs. However, the silent support from an adult who recognised the problems without responding was an ambiguous frame. The child sometimes felt betrayed. Concentrating on frames of recognition which could be passed over to professional interactions, we noticed that participants called for a safe harbour, providing a sense of normality. Being with friends and their families, escaping difficulties at home without having to tell, was emphasised as important. Recognition was experienced when an adult with respect and dignity offered an open opportunity to address the problems, without pushing towards further communication. Our study indicates some specific lessons to be learnt about recognition for professional service providers from everyday situations. Frames of recognition, communicating availability and normality, and also unconditional confidentiality and safety when sharing problems may also be offered by professionals in public healthcare within their current frames of competency and time.

The problem analysis for empirical studies

NARCIS (Netherlands)

Groenland, E.A.G.

2014-01-01

This article proposes a systematic methodology for the development of a problem analysis for cross-sectional, empirical research. This methodology is referred to as the 'Annabel approach'. It is suitable both for academic studies and applied (business) studies. In addition it can be used for both

The art and science of problem solving

DEFF Research Database (Denmark)

Vidal, Rene Victor Valqui

2005-01-01

In this paper we will document that real-life problem solving in complex situations demands both rational (scientific) and intuitive (artistic) thinking. First, the concepts of art and science will be discussed; differences and similarities will be enhanced. Thereafter the concept of group problem...... solving facilitation both as science and art will be presented. A case study related to examination's planning will be discussed to illustrate the main concepts in practice. In addition, other cases studies will also be shortly presented....

Language and modeling word problems in mathematics among bilinguals.

Science.gov (United States)

Bernardo, Allan B I

2005-09-01

The study was conducted to determine whether the language of math word problems would affect how Filipino-English bilingual problem solvers would model the structure of these word problems. Modeling the problem structure was studied using the problem-completion paradigm, which involves presenting problems without the question. The paradigm assumes that problem solvers can infer the appropriate question of a word problem if they correctly grasp its problem structure. Arithmetic word problems in Filipino and English were given to bilingual students, some of whom had Filipino as a first language and others who had English as a first language. The problem-completion data and solution data showed similar results. The language of the problem had no effect on problem-structure modeling. The results were discussed in relation to a more circumscribed view about the role of language in word problem solving among bilinguals. In particular, the results of the present study showed that linguistic factors do not affect the more mathematically abstract components of word problem solving, although they may affect the other components such as those related to reading comprehension and understanding.

Similarity Theory and Dimensionless Numbers in Heat Transfer

Science.gov (United States)

Marin, E.; Calderon, A.; Delgado-Vasallo, O.

2009-01-01

We present basic concepts underlying the so-called similarity theory that in our opinion should be explained in basic undergraduate general physics courses when dealing with heat transport problems, in particular with those involving natural or free convection. A simple example is described that can be useful in showing a criterion for neglecting…

Study on ant colony optimization for fuel loading pattern problem

International Nuclear Information System (INIS)

Kishi, Hironori; Kitada, Takanori

2013-01-01

Modified ant colony optimization (ACO) was applied to the in-core fuel loading pattern (LP) optimization problem to minimize the power peaking factor (PPF) in the modeled 1/4 symmetry PWR core. Loading order was found to be important in ACO. Three different loading orders with and without the adjacent effect between fuel assemblies (FAs) were compared, and it was found that the loading order from the central core is preferable because many selections of FAs to be inserted are available in the core center region. LPs were determined from pheromone trail and heuristic information, which is a priori knowledge based on the feature of the problem. Three types of heuristic information were compared to obtain the desirable performance of searching LPs with low PPF. Moreover, mutation operation, such as the genetic algorithm (GA), was introduced into the ACO algorithm to avoid searching similar LPs because heuristic information used in ACO tends to localize the searching space in the LP problem. The performance of ACO with some improvement was compared with those of simulated annealing and GA. In conclusion, good performance can be achieved by setting proper heuristic information and mutation operation parameter in ACO. (author)

Study over problems related to fuel and ash handling systems; Probleminventering braensle- och askhantering

Energy Technology Data Exchange (ETDEWEB)

Njurell, Rolf; Wikman, Karin [AaF-Energi och Miljoe AB, Stockhom (Sweden)

2003-10-01

There have been a lot of problems related to fuel and ash handling systems since the combustion of different types of biofuels started in the 70s. Many measures have been taken to solve some of the problems, but others have become part of the daily work. The purpose of this study has been to do a compilation of the fuel and ash handling problems that exist at different types of heat and power plants. The study over problems related to fuel and ash handling systems has been carried out through a questionnaire via the Internet. Directors at about 150 energy production plants were contacted by phone or e-mail in the beginning of the project and asked to participate in the study. 72 of these plants accepted to fill in the questionnaire. After several reminders by e-mails and phone calls there were in the end 32 plants that completed the form. Together they reported about 25 problems related to fuel handling and 27 problems related to ash handling. In general each of the plants reported one problem of each kind. Even if the material from the questionnaire is not enough to make statistical analysis a few conclusions can be made about the most common problems, the cause of the problems and where they appear. Fuel handling problems that occur at several plants are stoppage in the conveying equipment, bridging in the boiler silo or the tipping bunker and problems with the sieve for separation. The distribution of the fuel handling problems is almost equal for all equipment parts (receiving, separation, transport etc.). For the ash handling systems problems with transport of dry bottom ash dominate, followed by and the moistening of fly ash and transport of wet bottom ash. Most of the problems related to fuel handling are caused by the fuel quality. For example several plants have reported that bark is a fuel that is hard to handle. Nevertheless the quality for a specific fuel is not always bad when it is delivered to the plant but the fuel quality might change during

Early determinants of attention and hyperactivity problems in adolescents: the 11-year follow-up of the 1993 Pelotas (Brazil) birth cohort study.

Science.gov (United States)

Anselmi, Luciana; Menezes, Ana M B; Barros, Fernando C; Hallal, Pedro C; Araújo, Cora Luiza; Domingues, Marlos R; Rohde, Luis A

2010-10-01

The aim of this study was to assess early determinants of attention and hyperactivity problems in adolescents. In 1993, all hospital births in the city of Pelotas, Rio Grande do Sul State, Brazil, were monitored and mothers were interviewed (N = 5,249). At 11 years of age, 4,423 mothers answered the Strengths and Difficulties Questionnaire (SDQ) in order to evaluate attention and hyperactivity problems in the adolescents. Crude and adjusted prevalence ratios were calculated using Poisson regression. Prevalence of attention and hyperactivity problems was 19.9%. Factors associated with the outcome in the adjusted analysis were: male gender, low family income, smoking during pregnancy, minor psychiatric disorders in the mother, and history of child's behavioral/emotional problems at four years of age. Early life events impacted attention and hyperactivity problems in adolescence. Risk factors for attention and hyperactivity problems found in this study were similar to those reported in other cultures.

INFORMATIVE ENERGY METRIC FOR SIMILARITY MEASURE IN REPRODUCING KERNEL HILBERT SPACES

Directory of Open Access Journals (Sweden)

Songhua Liu

2012-02-01

Full Text Available In this paper, information energy metric (IEM is obtained by similarity computing for high-dimensional samples in a reproducing kernel Hilbert space (RKHS. Firstly, similar/dissimilar subsets and their corresponding informative energy functions are defined. Secondly, IEM is proposed for similarity measure of those subsets, which converts the non-metric distances into metric ones. Finally, applications of this metric is introduced, such as classification problems. Experimental results validate the effectiveness of the proposed method.

Distributional Similarity for Chinese: Exploiting Characters and Radicals

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Peng Jin

2012-01-01

Full Text Available Distributional Similarity has attracted considerable attention in the field of natural language processing as an automatic means of countering the ubiquitous problem of sparse data. As a logographic language, Chinese words consist of characters and each of them is composed of one or more radicals. The meanings of characters are usually highly related to the words which contain them. Likewise, radicals often make a predictable contribution to the meaning of a character: characters that have the same components tend to have similar or related meanings. In this paper, we utilize these properties of the Chinese language to improve Chinese word similarity computation. Given a content word, we first extract similar words based on a large corpus and a similarity score for ranking. This rank is then adjusted according to the characters and components shared between the similar word and the target word. Experiments on two gold standard datasets show that the adjusted rank is superior and closer to human judgments than the original rank. In addition to quantitative evaluation, we examine the reasons behind errors drawing on linguistic phenomena for our explanations.

Trajectories of mental health problems in children of parents with mental health problems: results of the BELLA study.

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Plass-Christl, Angela; Otto, Christiane; Klasen, Fionna; Wiegand-Grefe, Silke; Barkmann, Claus; Hölling, Heike; Schulte-Markwort, Michael; Ravens-Sieberer, Ulrike

2017-11-24

Children of parents with mental health problems (CPM) have an increased risk for behavioral and psychological problems. This study investigated the age- and gender-specific course as well as predictors of mental health problems in CPM using the longitudinal data (baseline 1- and 2-year follow-ups) of a German general population sample from the BELLA study. Children and adolescents aged 11-17 years (at baseline) who had a parent with mental health problems (n = 325) were analyzed. The mental health problems of the children were assessed by the self-reported version of the strengths and difficulties questionnaire (SDQ). We used individual growth modeling to investigate the age- and gender-specific course, and the effects of risk as well as personal, familial and social protective factors on self-reported mental health problems in CPM. Additionally, data were examined differentiating internalizing and externalizing mental health problems in CPM. Results indicated that female compared to male CPM showed increasing mental health problems with increasing age. Mental health problems in CPM were associated with lower self-efficacy, worse family climate and less social competence over time. Internalizing problems were associated with lower self-efficacy, less social competence and more severe parental mental health problems. Externalizing problems were associated with lower self-efficacy, worse family climate and lower social competence. The main limitations of the study are the short time period (2 years) covered and the report of mental health problems by only one parent. Our findings should be considered in the development of treatment and prevention programs for mental health problems in CPM.

Extending the Similarity-Attraction Effect: The Effects of When-Similarity in Computer-Mediated Communication

NARCIS (Netherlands)

Kaptein, M.C.; Castaneda, D.; Fernandez, N.; Nass, C.

2014-01-01

The feeling of connectedness experienced in computer-mediated relationships can be explained by the similarity-attraction effect (SAE). Though SAE is well established in psychology, the effects of some types of similarity have not yet been explored. In 2 studies, we demonstrate similarity-attraction

Counterfactual Problem Solving and Situated Cognition

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Glebkin V.V.,

2017-08-01

Full Text Available The paper describes and interprets data of a study on counterfactual problem solving in representatives of modern industrial culture. The study was inspired by similar experiments carried out by A.R. Luria during his expedition to Central Asia. The hypothesis of our study was that representatives of modern industrial culture would solve counterfactual puzzles at a slower rate and with higher numbers of mistakes than similar non-counterfactual tasks. The experiments we conducted supported this hypothesis as well as provided us with some insights as to how to further develop it. For instance, we found no significant differences in time lag in solving counterfactual and ‘realistic’ tasks between the subjects with mathematical and the ones with liberal arts education. As an interpretation of the obtained data, we suggest a two-stage model of counterfactual problem solving: on the first stage, where situated cognition dominates, the realistic situation is transferred into the system of symbols unrelated to this very situation; on the second stage, operations are carried out within the framework of this new system of symbols.

Tacit knowledge of public health nurses in identifying community health problems and need for new services: a case study.

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Yoshioka-Maeda, Kyoko; Murashima, Sachiyo; Asahara, Kiyomi

2006-09-01

The purpose of this study was to explore the tacit knowledge of public health nurses in identifying community health problems and developing relevant new projects. Previous research only roughly showed those skills for creating new community health services, such as lobbying. Nine Japanese public health nurses who had created new projects in their municipalities were selected by theoretical sampling and interviewed in 2002-2003. Yin's Case Study Method, especially the multiple-case study design, was used. All 9 public health nurses used similar approaches in identifying community health problems and the need for creating new services, even though their experiences differed and the kinds of projects varied. They identified the difficulties of clients, recognized clients who had the same problems, elucidated the limitations of existing services, and forecasted outcomes from the neglect of the clients' problems. Then they succeeded in creating a new project by examining individual health problems in the context of their community's characteristics, societal factors, and using existing policies to support their clients. This is the first study to explore the skills of public health nurses and their intention to use such skills in creating new projects as well as the exact process. They could identify community health problems that will be the basis for developing new services to provide care for individual clients. This is different from the traditional community assessment approach that requires the collection of a huge amount of information to clarify community health problems. The tacit knowledge of public health nurses will help to create needs-oriented new services more smoothly.

Morphological similarity and ecological overlap in two rotifer species.

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Gabaldón, Carmen; Montero-Pau, Javier; Serra, Manuel; Carmona, María José

2013-01-01

Co-occurrence of cryptic species raises theoretically relevant questions regarding their coexistence and ecological similarity. Given their great morphological similitude and close phylogenetic relationship (i.e., niche retention), these species will have similar ecological requirements and are expected to have strong competitive interactions. This raises the problem of finding the mechanisms that may explain the coexistence of cryptic species and challenges the conventional view of coexistence based on niche differentiation. The cryptic species complex of the rotifer Brachionus plicatilis is an excellent model to study these questions and to test hypotheses regarding ecological differentiation. Rotifer species within this complex are filtering zooplankters commonly found inhabiting the same ponds across the Iberian Peninsula and exhibit an extremely similar morphology-some of them being even virtually identical. Here, we explore whether subtle differences in body size and morphology translate into ecological differentiation by comparing two extremely morphologically similar species belonging to this complex: B. plicatilis and B. manjavacas. We focus on three key ecological features related to body size: (1) functional response, expressed by clearance rates; (2) tolerance to starvation, measured by growth and reproduction; and (3) vulnerability to copepod predation, measured by the number of preyed upon neonates. No major differences between B. plicatilis and B. manjavacas were found in the response to these features. Our results demonstrate the existence of a substantial niche overlap, suggesting that the subtle size differences between these two cryptic species are not sufficient to explain their coexistence. This lack of evidence for ecological differentiation in the studied biotic niche features is in agreement with the phylogenetic limiting similarity hypothesis but requires a mechanistic explanation of the coexistence of these species not based on

Morphological similarity and ecological overlap in two rotifer species.

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Carmen Gabaldón

Full Text Available Co-occurrence of cryptic species raises theoretically relevant questions regarding their coexistence and ecological similarity. Given their great morphological similitude and close phylogenetic relationship (i.e., niche retention, these species will have similar ecological requirements and are expected to have strong competitive interactions. This raises the problem of finding the mechanisms that may explain the coexistence of cryptic species and challenges the conventional view of coexistence based on niche differentiation. The cryptic species complex of the rotifer Brachionus plicatilis is an excellent model to study these questions and to test hypotheses regarding ecological differentiation. Rotifer species within this complex are filtering zooplankters commonly found inhabiting the same ponds across the Iberian Peninsula and exhibit an extremely similar morphology-some of them being even virtually identical. Here, we explore whether subtle differences in body size and morphology translate into ecological differentiation by comparing two extremely morphologically similar species belonging to this complex: B. plicatilis and B. manjavacas. We focus on three key ecological features related to body size: (1 functional response, expressed by clearance rates; (2 tolerance to starvation, measured by growth and reproduction; and (3 vulnerability to copepod predation, measured by the number of preyed upon neonates. No major differences between B. plicatilis and B. manjavacas were found in the response to these features. Our results demonstrate the existence of a substantial niche overlap, suggesting that the subtle size differences between these two cryptic species are not sufficient to explain their coexistence. This lack of evidence for ecological differentiation in the studied biotic niche features is in agreement with the phylogenetic limiting similarity hypothesis but requires a mechanistic explanation of the coexistence of these species not

Problems in the Study of lineaments

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Anokhin, Vladimir; Kholmyanskii, Michael

2015-04-01

The study of linear objects in upper crust, called lineaments, led at one time to a major scientific results - discovery of the planetary regmatic network, the birth of some new tectonic concepts, establishment of new search for signs of mineral deposits. But now lineaments studied not enough for such a promising research direction. Lineament geomorphology has a number of problems. 1.Terminology problems. Lineament theme still has no generally accepted terminology base. Different scientists have different interpretations even for the definition of lineament We offer an expanded definition for it: lineaments - line features of the earth's crust, expressed by linear landforms, geological linear forms, linear anomalies of physical fields may follow each other, associated with faults. The term "lineament" is not identical to the term "fault", but always lineament - reasonable suspicion to fault, and this suspicion is justified in most cases. The structure lineament may include only the objects that are at least presumably can be attributed to the deep processes. Specialists in the lineament theme can overcome terminological problems if together create a common terminology database. 2. Methodological problems. Procedure manual selection lineaments mainly is depiction of straight line segments along the axes of linear morphostructures on some cartographic basis. Reduce the subjective factors of manual selection is possible, following a few simple rules: - The choice of optimal projection, scale and quality of cartographic basis; - Selection of the optimal type of linear objects under study; - The establishment of boundary conditions for the allocation lineament (minimum length, maximum bending, the minimum length to width ratio, etc.); - Allocation of an increasing number of lineaments - for representative sampling and reduce the influence of random errors; - Ranking lineaments: fine lines (rank 3) combined to form larger lineaments rank 2; which, when combined

Training Problems of Religious Studies in Independent Kazakhstan

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İlyas Erpay

2013-12-01

Full Text Available In the Republic of Kazakhstan training questions about religious studies still didn't receive enough attention since after statehood formation and before independence the Kazakhs endured a set of various historical events. Some of these events negatively affected people's consciousness. Seventy years of atheistic education changed people’s spiritual and cultural basis, as a result religious concepts partially lost the importance. After independence of the Republic of Kazakhstan started raise questions about teaching religious studies. However, heterogeneity in religious beliefs of the population to some extent negatively influences training in religious studies. Therefore study of the reasons for emergence of this problem turned into an actual problem. Within this article the genesis analysis of modern training problems in religious studies was carried out and ways of their decision were considered. Currently some religious studies teaching centers and preparation of the corresponding experts are formed. However, despite of the training standards are identical for all centers, ways of their implementation differ from each other. The reason for that – features of the outlook created under the influence of historical factors. These features cause necessity of teaching religious studies in high school. In article the questions on this problem was considered and necessary answers were given. The main method used in research work is the c omparative historical method. In summary it is necessary to specify that authors within article do the full analysis of questions of teaching of the subject "Religious studies" and offer solutions of these questions.

Problem solving of student with visual impairment related to mathematical literacy problem

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Pratama, A. R.; Saputro, D. R. S.; Riyadi

2018-04-01

The student with visual impairment, total blind category depends on the sense of touch and hearing in obtaining information. In fact, the two senses can receive information less than 20%. Thus, students with visual impairment of the total blind categories in the learning process must have difficulty, including learning mathematics. This study aims to describe the problem-solving process of the student with visual impairment, total blind category on mathematical literacy issues based on Polya phase. This research using test method similar problems mathematical literacy in PISA and in-depth interviews. The subject of this study was a student with visual impairment, total blind category. Based on the result of the research, problem-solving related to mathematical literacy based on Polya phase is quite good. In the phase of understanding the problem, the student read about twice by brushing the text and assisted with information through hearing three times. The student with visual impairment in problem-solving based on the Polya phase, devising a plan by summoning knowledge and experience gained previously. At the phase of carrying out the plan, students with visual impairment implement the plan in accordance with pre-made. In the looking back phase, students with visual impairment need to check the answers three times but have not been able to find a way.

A neural algorithm for a fundamental computing problem.

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Dasgupta, Sanjoy; Stevens, Charles F; Navlakha, Saket

2017-11-10

Similarity search-for example, identifying similar images in a database or similar documents on the web-is a fundamental computing problem faced by large-scale information retrieval systems. We discovered that the fruit fly olfactory circuit solves this problem with a variant of a computer science algorithm (called locality-sensitive hashing). The fly circuit assigns similar neural activity patterns to similar odors, so that behaviors learned from one odor can be applied when a similar odor is experienced. The fly algorithm, however, uses three computational strategies that depart from traditional approaches. These strategies can be translated to improve the performance of computational similarity searches. This perspective helps illuminate the logic supporting an important sensory function and provides a conceptually new algorithm for solving a fundamental computational problem. Copyright © 2017 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.

Postprocedural problems in an overdenture population: a longitudinal study.

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Ettinger, Ronald L; Qian, Fang

2004-05-01

This study reports on endodontic and other post-procedural problems experienced by overdenture patients from 1973 to 1996. There were 395 subjects enrolled in the study; 273 fulfilled the recall criteria. At recall, all subjects were examined by a single examiner, and appropriate maintenance care was performed. The 273 subjects had 666 abutments and 626 endodontically treated teeth; of these, 51 subjects had postprocedural problems in 81 teeth. Thus, 87.1% of the endodontically treated teeth had no postprocedural problems, and 12.9% had postprocedural problems. Of the subpopulation with postprocedural problems, the most common problem was endodontically treated teeth developing periradicular lesions (37.0%) because of recurrent caries causing loss of the restoration sealing the root canal. Twenty of the 30 teeth were successfully retreated. The next most common problem was vertical root fractures (30.9%), followed by vital teeth developing periradicular lesions (19.8%). Most of the failures could have been prevented by better oral hygiene. Vertical root fractures were statistically associated with abutments in the maxilla and opposed by natural teeth; protection of these abutments with thimble crowns could prevent fractures.

Using an isomorphic problem pair to learn introductory physics: Transferring from a two-step problem to a three-step problem

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Shih-Yin Lin

2013-10-01

Full Text Available In this study, we examine introductory physics students’ ability to perform analogical reasoning between two isomorphic problems which employ the same underlying physics principles but have different surface features. 382 students from a calculus-based and an algebra-based introductory physics course were administered a quiz in the recitation in which they had to learn from a solved problem provided and take advantage of what they learned from it to solve another isomorphic problem (which we call the quiz problem. The solved problem provided has two subproblems while the quiz problem has three subproblems, which is known from previous research to be challenging for introductory students. In addition to the solved problem, students also received extra scaffolding supports that were intended to help them discern and exploit the underlying similarities of the isomorphic solved and quiz problems. The data analysis suggests that students had great difficulty in transferring what they learned from a two-step problem to a three-step problem. Although most students were able to learn from the solved problem to some extent with the scaffolding provided and invoke the relevant principles in the quiz problem, they were not necessarily able to apply the principles correctly. We also conducted think-aloud interviews with six introductory students in order to understand in depth the difficulties they had and explore strategies to provide better scaffolding. The interviews suggest that students often superficially mapped the principles employed in the solved problem to the quiz problem without necessarily understanding the governing conditions underlying each principle and examining the applicability of the principle in the new situation in an in-depth manner. Findings suggest that more scaffolding is needed to help students in transferring from a two-step problem to a three-step problem and applying the physics principles appropriately. We outline a few

Using an isomorphic problem pair to learn introductory physics: Transferring from a two-step problem to a three-step problem

Science.gov (United States)

Lin, Shih-Yin; Singh, Chandralekha

2013-12-01

In this study, we examine introductory physics students’ ability to perform analogical reasoning between two isomorphic problems which employ the same underlying physics principles but have different surface features. 382 students from a calculus-based and an algebra-based introductory physics course were administered a quiz in the recitation in which they had to learn from a solved problem provided and take advantage of what they learned from it to solve another isomorphic problem (which we call the quiz problem). The solved problem provided has two subproblems while the quiz problem has three subproblems, which is known from previous research to be challenging for introductory students. In addition to the solved problem, students also received extra scaffolding supports that were intended to help them discern and exploit the underlying similarities of the isomorphic solved and quiz problems. The data analysis suggests that students had great difficulty in transferring what they learned from a two-step problem to a three-step problem. Although most students were able to learn from the solved problem to some extent with the scaffolding provided and invoke the relevant principles in the quiz problem, they were not necessarily able to apply the principles correctly. We also conducted think-aloud interviews with six introductory students in order to understand in depth the difficulties they had and explore strategies to provide better scaffolding. The interviews suggest that students often superficially mapped the principles employed in the solved problem to the quiz problem without necessarily understanding the governing conditions underlying each principle and examining the applicability of the principle in the new situation in an in-depth manner. Findings suggest that more scaffolding is needed to help students in transferring from a two-step problem to a three-step problem and applying the physics principles appropriately. We outline a few possible strategies

Eye-Tracking Study of Complexity in Gas Law Problems

Science.gov (United States)

Tang, Hui; Pienta, Norbert

2012-01-01

This study, part of a series investigating students' use of online tools to assess problem solving, uses eye-tracking hardware and software to explore the effect of problem difficulty and cognitive processes when students solve gas law word problems. Eye movements are indices of cognition; eye-tracking data typically include the location,…

The art and science of participative problem solving

DEFF Research Database (Denmark)

Vidal, Rene Victor Valqui

In this paper we will document that real-life problem solving in complex situations demands both rational (scientific) and intuitive (artistic) thinking. First, the concepts of art and science will be discussed; differences and similarities will be enhanced. Thereafter the concept of group problem...... solving facilitation both as science and art will be presented. A case study related to examinations planning will be discussed to illustrate the main concepts in practice. In addition, other cases studies will also be shortly presented....

Structure modulates similarity-based interference in sluicing: An eye tracking study.

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Jesse A. Harris

2015-12-01

Full Text Available In cue-based content-addressable approaches to memory, a target and its competitors are retrieved in parallel from memory via a fast, associative cue-matching procedure under a severely limited focus of attention. Such a parallel matching procedure could in principle ignore the serial order or hierarchical structure characteristic of linguistic relations. I present an eye tracking while reading experiment that investigates whether the sentential position of a potential antecedent modulates the strength of similarity-based interference, a well-studied effect in which increased similarity in features between a target and its competitors results in slower and less accurate retrieval overall. The manipulation trades on an independently established Locality bias in sluiced structures to associate a wh-remnant (which ones in clausal ellipsis with the most local correlate (some wines, as in The tourists enjoyed some wines, but I don’t know which ones. The findings generally support cue-based parsing models of sentence processing that are subject to similarity-based interference in retrieval, and provide additional support to the growing body of evidence that retrieval is sensitive to both the structural position of a target antecedent and its competitors, and the specificity of retrieval cues.

Self-similar variables and the problem of nonlocal electron heat conductivity

International Nuclear Information System (INIS)

Krasheninnikov, S.I.; Bakunin, O.G.

1993-10-01

Self-similar solutions of the collisional electron kinetic equation are obtained for the plasmas with one (1D) and three (3D) dimensional plasma parameter inhomogeneities and arbitrary Z eff . For the plasma parameter profiles characterized by the ratio of the mean free path of thermal electrons with respect to electron-electron collisions, γ T , to the scale length of electron temperature variation, L, one obtains a criterion for determining the effect that tail particles with motion of the non-diffusive type have on the electron heat conductivity. For these conditions it is shown that the use of a open-quotes symmetrizedclose quotes kinetic equation for the investigation of the strong nonlocal effect of suprathermal electrons on the electron heat conductivity is only possible at sufficiently high Z eff (Z eff ≥ (L/γ T ) 1/2 ). In the case of 3D inhomogeneous plasma (spherical symmetry), the effect of the tail electrons on the heat transport is less pronounced since they are spread across the radius r

Behavioral Problems in Iranian Epileptic Children; A Case Control Study

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Maryam Aludari

2017-12-01

Full Text Available Background Epilepsy is among the most common neurological disorders in childhood, prevalence of which is increasing. Unpredictable and chronic nature of the disease affects physical, social and mental functions of the children and their family. This study was aimed to compare behavioral problems in epileptic children group versus healthy control group. Materials and Methods This study is a case-control one conducted from January 2013 to June 2016 in Tehran, Iran. The epileptic children in age of 7-10 years old that were diagnosed by neurologist referred to the researcher for further process. Their parents were provided with Child Behavior Checklist (CBCL to be completed. For matching by age and gender, the healthy group was sampled after the epilepsy group. Multivariate Analysis of Variance was used for statistical analysis. Results In this study 94 children with epilepsy and 83 healthy children in age of 7-10 years old were studied. The results indicated that there were significantly higher behavioral problems in the children with epilepsy than in control group in nine categories of seclusiveness, physical complaints, anxiety and depression, social problems, thought problems, attention problems, delinquent behaviors, aggressive behaviors, and other problems. Comparison of two generalized and partial epilepsy groups indicated that there was a significant difference only in attention problems (p = 0.024. Conclusion The present study indicates that the children with epilepsy have more behavioral problems as compared to control group. Therefore, educational and psychological interventions are necessary for supporting desirable psychosocial growth and development of such children.

Similar Symmetries: The Role of Wallpaper Groups in Perceptual Texture Similarity

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Fraser Halley

2011-05-01

Full Text Available Periodic patterns and symmetries are striking visual properties that have been used decoratively around the world throughout human history. Periodic patterns can be mathematically classified into one of 17 different Wallpaper groups, and while computational models have been developed which can extract an image's symmetry group, very little work has been done on how humans perceive these patterns. This study presents the results from a grouping experiment using stimuli from the different wallpaper groups. We find that while different images from the same wallpaper group are perceived as similar to one another, not all groups have the same degree of self-similarity. The similarity relationships between wallpaper groups appear to be dominated by rotations.

Color-Based Image Retrieval from High-Similarity Image Databases

DEFF Research Database (Denmark)

Hansen, Michael Adsetts Edberg; Carstensen, Jens Michael

2003-01-01

Many image classification problems can fruitfully be thought of as image retrieval in a "high similarity image database" (HSID) characterized by being tuned towards a specific application and having a high degree of visual similarity between entries that should be distinguished. We introduce...... a method for HSID retrieval using a similarity measure based on a linear combination of Jeffreys-Matusita (JM) distances between distributions of color (and color derivatives) estimated from a set of automatically extracted image regions. The weight coefficients are estimated based on optimal retrieval...... performance. Experimental results on the difficult task of visually identifying clones of fungal colonies grown in a petri dish and categorization of pelts show a high retrieval accuracy of the method when combined with standardized sample preparation and image acquisition....

A qualitative study of health problems, risk factors, and prevention among Emergency Medical Service workers.

Science.gov (United States)

Dropkin, Jonathan; Moline, Jacqueline; Power, Paul M; Kim, Hyun

2015-01-01

Risk factors among Emergency Medical Service (EMS) workers are difficult to characterize and inconsistencies remain about their main health problems. To identify main work-related health problems among EMS workers in the United States; identify risk factors at the organizational, task, and exposure level; identify prevention strategies; examine these issues between participants (EMS workers and supervisors). Two types of qualitative research methods based on grounded theory were used: in-depth interviews with emergency medical technicians/paramedics (EMS workers) and focus groups (EMS workers and supervisors). Most participants reported similar health problems (musculoskeletal injuries) and the task related to these injuries, patient handling. Participants also reported similar physical exposures (ascending stairs with patients and patient weight). For organization/psychosocial factors, participants agreed that fitness, wages, breaks, and shift scheduling were linked with injuries, but overall, perceptions about these issues differed more than physical exposures. Lack of trust between EMS workers and supervisors were recurrent concerns among workers. However, not all organizational/psychosocial factors differed. EMS workers and supervisors agreed pre-employment screening could reduce injuries. Participants identified micro- and macro-level prevention opportunities. The grounded theory approach identified workers' main health problems, and the organizational factors and exposures linked with them. Perceptions about work organization/psychosocial exposures appeared more diverse than physical exposures. Prevention among all participants focused on mechanized equipment, but EMS workers also wanted more organizational support.

Justification for the Subject of Congruence and Similarity in the Context of Daily Life and Conceptual Knowledge

Science.gov (United States)

Dündar, Sefa; Gündüz, Nazan

2017-01-01

This study aims to examine prospective elementary mathematics teachers' conceptual knowledge level for congruence and similarity in triangles subject and to examine their ability to represent the knowledge, to associate the knowledge with daily life, and to justify and solve the geometry problems about this subject. The study is designed in a…

Research Projects in Physics: A Mechanism for Teaching Ill-Structured Problem Solving

Science.gov (United States)

Milbourne, Jeff; Bennett, Jonathan

2017-01-01

Physics education research has a tradition of studying problem solving, exploring themes such as physical intuition and differences between expert and novice problem solvers. However, most of this work has focused on traditional, or well-structured, problems, similar to what might appear in a textbook. Less work has been done with open-ended, or…

POISSON, Analysis Solution of Poisson Problems in Probabilistic Risk Assessment

International Nuclear Information System (INIS)

Froehner, F.H.

1986-01-01

1 - Description of program or function: Purpose of program: Analytic treatment of two-stage Poisson problem in Probabilistic Risk Assessment. Input: estimated a-priori mean failure rate and error factor of system considered (for calculation of stage-1 prior), number of failures and operating times for similar systems (for calculation of stage-2 prior). Output: a-posteriori probability distributions on linear and logarithmic time scale (on specified time grid) and expectation values of failure rate and error factors are calculated for: - stage-1 a-priori distribution, - stage-1 a-posteriori distribution, - stage-2 a-priori distribution, - stage-2 a-posteriori distribution. 2 - Method of solution: Bayesian approach with conjugate stage-1 prior, improved with experience from similar systems to yield stage-2 prior, and likelihood function from experience with system under study (documentation see below under 10.). 3 - Restrictions on the complexity of the problem: Up to 100 similar systems (including the system considered), arbitrary number of problems (failure types) with same grid

Commonalities in the psychological factors associated with problem gambling and Internet dependence.

Science.gov (United States)

Dowling, N A; Brown, M

2010-08-01

The most commonly applied conceptual approach for excessive Internet use has been as a behavioral addiction, similar to pathological or problem gambling. In order to contribute to the understanding of Internet dependence as a disorder resembling problem gambling, the current study aimed to examine the relationship between problem gambling and Internet dependence and the degree to which psychological factors associated with problem gambling are relevant to the study of Internet dependence. The factors of depression, anxiety, student stressors, loneliness, and social support were examined in a sample of university students from several Australian universities. The findings revealed that there is no overlap between the populations reporting problem gambling and Internet dependence, but that individuals with these disorders report similar psychological profiles. Although requiring replication with larger community samples and longitudinal designs, these preliminary findings suggest that problem gambling and Internet dependence may be separate disorders with common underlying etiologies or consequences. The implications of the findings in relation to the conceptualization and management of these disorders are briefly discussed.

Developing non-routine problems for assessing students’ mathematical literacy

Science.gov (United States)

Murdiyani, N. M.

2018-03-01

The purpose of this study is to develop non-routine problems for assessing the mathematics literacy skills of students, which is valid, practical, and effective. It is based on the previous research said that Indonesian students’ mathematical literacy is still low. The results of this study can be used as a guide in developing the evaluation questions that can train students to improve the ability of solving non-routine problems in everyday life. This research type is formative evaluation that consists of preliminary, self evaluation, expert reviews, one-to-one, small group, and field test. The sample of this research is grade 8 students at one of Junior High School in Yogyakarta. This study results in mathematics literacy problems prototype consisting of level 1 to level 6 problems similar to PISA problems. This study also discusses the examples of students’ answer and their reasoning.

Analysis of metal forming processes by using physical modeling and new plastic similarity condition

International Nuclear Information System (INIS)

Gronostajski, Z.; Hawryluk, M.

2007-01-01

In recent years many advances have been made in numerical methods, for linear and non-linear problems. However the success of them depends very much on the correctness of the problem formulation and the availability of the input data. Validity of the theoretical results can be verified by an experiment using the real or soft materials. An essential reduction of time and costs of the experiment can be obtained by using soft materials, which behaves in a way analogous to that of real metal during deformation. The advantages of using of the soft materials are closely connected with flow stress 500 to 1000 times lower than real materials. The accuracy of physical modeling depend on the similarity conditions between physical model and real process. The most important similarity conditions are materials similarity in the range of plastic and elastic deformation, geometrical, frictional and thermal similarities. New original plastic similarity condition for physical modeling of metal forming processes is proposed in the paper. It bases on the mathematical description of similarity of the flow stress curves of soft materials and real ones

The evaluator effect in usability studies: Problem detection and severity judgments

DEFF Research Database (Denmark)

Jacobsen, Niels Ebbe; Hertzum, Morten; John, Bonnie E.

1998-01-01

Usability studies are commonly used in industry and applied in research as a yardstick for other usability evaluation methods. Though usability studies have been studied extensively, one potential threat to their reliability has been left virtually untouched: the evaluator effect. In this study......, four evaluators individually analyzed four videotaped usability test sessions. Only 20% of the 93 detected problems were detected by all evaluators, and 46% were detected by only a single evaluator. From the total set of 93 problems the evaluators individually selected the ten problems they considered...... most severe. None of the selected severe problems appeared on all four evaluators’ top-10 lists, and 4 of the 11 problems that were considered severe by more than one evaluator were only detected by one or two evaluators. Thus, both detection of usability problems and selection of the most severe...

Sherlock: A Semi-automatic Framework for Quiz Generation Using a Hybrid Semantic Similarity Measure.

Science.gov (United States)

Lin, Chenghua; Liu, Dong; Pang, Wei; Wang, Zhe

In this paper, we present a semi-automatic system (Sherlock) for quiz generation using linked data and textual descriptions of RDF resources. Sherlock is distinguished from existing quiz generation systems in its generic framework for domain-independent quiz generation as well as in the ability of controlling the difficulty level of the generated quizzes. Difficulty scaling is non-trivial, and it is fundamentally related to cognitive science. We approach the problem with a new angle by perceiving the level of knowledge difficulty as a similarity measure problem and propose a novel hybrid semantic similarity measure using linked data. Extensive experiments show that the proposed semantic similarity measure outperforms four strong baselines with more than 47 % gain in clustering accuracy. In addition, we discovered in the human quiz test that the model accuracy indeed shows a strong correlation with the pairwise quiz similarity.

Quenching rate for a nonlocal problem arising in the micro-electro mechanical system

Science.gov (United States)

Guo, Jong-Shenq; Hu, Bei

2018-03-01

In this paper, we study the quenching rate of the solution for a nonlocal parabolic problem which arises in the study of the micro-electro mechanical system. This question is equivalent to the stabilization of the solution to the transformed problem in self-similar variables. First, some a priori estimates are provided. In order to construct a Lyapunov function, due to the lack of time monotonicity property, we then derive some very useful and challenging estimates by a delicate analysis. Finally, with this Lyapunov function, we prove that the quenching rate is self-similar which is the same as the problem without the nonlocal term, except the constant limit depends on the solution itself.

Behavioral/Emotional Problems of Preschoolers: Caregiver/Teacher Reports from 15 Societies

Science.gov (United States)

Rescorla, Leslie A.; Achenbach, Thomas M.; Ivanova, Masha Y.; Bilenberg, Niels; Bjarnadottir, Gudrun; Denner, Silvia; Dias, Pedro; Dobrean, Anca; Dopfner, Manfred; Frigerio, Alessandra; Goncalves, Miguel; Guomundsson, Halldor; Jusiene, Roma; Kristensen, Solvejg; Lecannelier, Felipe; Leung, Patrick W. L.; Liu, Jianghong; Lobel, Sofia P.; Machado, Barbara Cesar; Markovic, Jasminka; Mas, Paola A.; Esmaeili, Elaheh Mohammad; Montirosso, Rosario; Pluck, Julia; Pronaj, Adelina Ahmeti; Rodriguez, Jorge T.; Rojas, Pamela O.; Schmeck, Klaus; Shahini, Mimoza; Silva, Jaime R.; van der Ende, Jan; Verhulst, Frank C.

2012-01-01

This study tested societal effects on caregiver/teacher ratings of behavioral/emotional problems for 10,521 preschoolers from 15 societies. Many societies had problem scale scores within a relatively narrow range, despite differences in language, culture, and other characteristics. The small age and gender effects were quite similar across…

Similar problems, different solutions: comparing refuse collection in the Netherlands and Spain.

Science.gov (United States)

Bel, Germà; Fageda, Xavier; Dijkgraaf, Elbert; Gradus, Raymond

2010-01-01

Because of differences in institutional arrangements, public service markets, and national traditions regarding government intervention, local public service provision can vary greatly. In this paper we compare the procedures adopted by the local governments of The Netherlands and Spain in arranging for the provision of solid waste collection. We find that Spain faces a problem of consolidation, opting more frequently to implement policies of privatization and cooperation, at the expense of competition. By contrast, The Netherlands, which has larger municipalities on average, resorts somewhat less to privatization and cooperation, and more to competition. Both options-cooperation and competition-have their merits when striving to strike a balance between transaction costs and scale economies. The choices made in organizational reform seem to be related to several factors, among which the nature of the political system and the size of municipalities appear to be relevant.

QSAR and docking studies of anthraquinone derivatives by similarity cluster prediction.

Science.gov (United States)

Harsa, Alexandra M; Harsa, Teodora E; Diudea, Mircea V

2016-01-01

Forty anthraquinone derivatives have been downloaded from PubChem database and investigated in a quantitative structure-activity relationships (QSAR) study. The models describing log P and LD50 of this set were built up on the hypermolecule scheme that mimics the investigated receptor space; the models were validated by the leave-one-out procedure, in the external test set and in a new version of prediction by using similarity clusters. Molecular docking approach using Lamarckian Genetic Algorithm was made on this class of anthraquinones with respect to 3Q3B receptor. The best scored molecules in the docking assay were used as leaders in the similarity clustering procedure. It is demonstrated that the LD50 data of this set of anthraquinones are related to the binding energies of anthraquinone ligands to the 3Q3B receptor.

Soliton shock wave fronts and self-similar discontinuities in dispersion hydrodynamics

International Nuclear Information System (INIS)

Gurevich, A.V.; Meshcherkin, A.P.

1987-01-01

Nonlinear flows in nondissipative dispersion hydrodynamics are examined. It is demonstrated that in order to describe such flows it is necessary to incorporate a new concept: a special discontinuity called a ''self-similar'' discontinuity consisting of a nondissipative shock wave and a powerful slow wave discontinuity in regular hydrodynamics. The ''self similar discontinuity'' expands linearly over time. It is demonstrated that this concept may be introduced in a solution to Euler equations. The boundary conditions of the ''self similar discontinuity'' that allow closure of Euler equations for dispersion hydrodynamics are formulated, i.e., those that replace the shock adiabatic curve of standard dissipative hydrodynamics. The structure of the soliton front and of the trailing edge of the shock wave is investigated. A classification and complete solution are given to the problem of the decay of random initial discontinuities in the hydrodynamics of highly nonisothermic plasma. A solution is derived to the problem of the decay of initial discontinuities in the hydrodynamics of magnetized plasma. It is demonstrated that in this plasma, a feature of current density arises at the point of soliton inversion

Dimensional analysis and self-similarity methods for engineers and scientists

CERN Document Server

Zohuri, Bahman

2015-01-01

This ground-breaking reference provides an overview of key concepts in dimensional analysis, and then pushes well beyond traditional applications in fluid mechanics to demonstrate how powerful this tool can be in solving complex problems across many diverse fields. Of particular interest is the book's coverage of  dimensional analysis and self-similarity methods in nuclear and energy engineering. Numerous practical examples of dimensional problems are presented throughout, allowing readers to link the book's theoretical explanations and step-by-step mathematical solutions to practical impleme

The traveling salesman problem a computational study

CERN Document Server

Applegate, David L; Chvatal, Vasek; Cook, William J

2006-01-01

This book presents the latest findings on one of the most intensely investigated subjects in computational mathematics--the traveling salesman problem. It sounds simple enough: given a set of cities and the cost of travel between each pair of them, the problem challenges you to find the cheapest route by which to visit all the cities and return home to where you began. Though seemingly modest, this exercise has inspired studies by mathematicians, chemists, and physicists. Teachers use it in the classroom. It has practical applications in genetics, telecommunications, and neuroscience.

Logarithmic Similarity Measure between Interval-Valued Fuzzy Sets and Its Fault Diagnosis Method

Directory of Open Access Journals (Sweden)

Zhikang Lu

2018-02-01

Full Text Available Fault diagnosis is an important task for the normal operation and maintenance of equipment. In many real situations, the diagnosis data cannot provide deterministic values and are usually imprecise or uncertain. Thus, interval-valued fuzzy sets (IVFSs are very suitable for expressing imprecise or uncertain fault information in real problems. However, existing literature scarcely deals with fault diagnosis problems, such as gasoline engines and steam turbines with IVFSs. However, the similarity measure is one of the important tools in fault diagnoses. Therefore, this paper proposes a new similarity measure of IVFSs based on logarithmic function and its fault diagnosis method for the first time. By the logarithmic similarity measure between the fault knowledge and some diagnosis-testing samples with interval-valued fuzzy information and its relation indices, we can determine the fault type and ranking order of faults corresponding to the relation indices. Then, the misfire fault diagnosis of the gasoline engine and the vibrational fault diagnosis of a turbine are presented to demonstrate the simplicity and effectiveness of the proposed diagnosis method. The fault diagnosis results of gasoline engine and steam turbine show that the proposed diagnosis method not only gives the main fault types of the gasoline engine and steam turbine but also provides useful information for multi-fault analyses and predicting future fault trends. Hence, the logarithmic similarity measure and its fault diagnosis method are main contributions in this study and they provide a useful new way for the fault diagnosis with interval-valued fuzzy information.

Solution of the weighted symmetric similarity transformations based on quaternions

Science.gov (United States)

Mercan, H.; Akyilmaz, O.; Aydin, C.

2017-12-01

A new method through Gauss-Helmert model of adjustment is presented for the solution of the similarity transformations, either 3D or 2D, in the frame of errors-in-variables (EIV) model. EIV model assumes that all the variables in the mathematical model are contaminated by random errors. Total least squares estimation technique may be used to solve the EIV model. Accounting for the heteroscedastic uncertainty both in the target and the source coordinates, that is the more common and general case in practice, leads to a more realistic estimation of the transformation parameters. The presented algorithm can handle the heteroscedastic transformation problems, i.e., positions of the both target and the source points may have full covariance matrices. Therefore, there is no limitation such as the isotropic or the homogenous accuracy for the reference point coordinates. The developed algorithm takes the advantage of the quaternion definition which uniquely represents a 3D rotation matrix. The transformation parameters: scale, translations, and the quaternion (so that the rotation matrix) along with their covariances, are iteratively estimated with rapid convergence. Moreover, prior least squares (LS) estimation of the unknown transformation parameters is not required to start the iterations. We also show that the developed method can also be used to estimate the 2D similarity transformation parameters by simply treating the problem as a 3D transformation problem with zero (0) values assigned for the z-components of both target and source points. The efficiency of the new algorithm is presented with the numerical examples and comparisons with the results of the previous studies which use the same data set. Simulation experiments for the evaluation and comparison of the proposed and the conventional weighted LS (WLS) method is also presented.

δ-Similar Elimination to Enhance Search Performance of Multiobjective Evolutionary Algorithms

Science.gov (United States)

Aguirre, Hernán; Sato, Masahiko; Tanaka, Kiyoshi

In this paper, we propose δ-similar elimination to improve the search performance of multiobjective evolutionary algorithms in combinatorial optimization problems. This method eliminates similar individuals in objective space to fairly distribute selection among the different regions of the instantaneous Pareto front. We investigate four eliminating methods analyzing their effects using NSGA-II. In addition, we compare the search performance of NSGA-II enhanced by our method and NSGA-II enhanced by controlled elitism.

Longitudinal effects of sibling relationship quality on adolescent problem behavior: a cross-ethnic comparison.

Science.gov (United States)

Buist, Kirsten L; Paalman, Carmen H; Branje, Susan J T; Deković, Maja; Reitz, Ellen; Verhoeven, Marjolein; Meeus, Wim H J; Koot, Hans M; Hale, William W

2014-04-01

The aim of the present study was to examine whether adolescents of Moroccan and Dutch origin differ concerning sibling relationship quality and to examine whether the associations between quality of the sibling relationship and level and change in externalizing and internalizing problem behavior are comparable for Moroccan and Dutch adolescents. Five annual waves of questionnaire data on sibling support and conflict as well as externalizing problems, anxiety and depression were collected from 159 ethnic Moroccan adolescents (Mage = 13.3 years) and from 159 ethnic Dutch adolescents (Mage = 13.0 years). Our findings demonstrated significant mean level differences between the Moroccan and Dutch sample in sibling relationship quality, externalizing problems, and depression, with Moroccan adolescents reporting higher sibling relationship quality and less problem behavior. However, effects of sibling relationship quality on externalizing problems, anxiety, and depression were similar for the Moroccan and Dutch samples. Sibling support was not related to level of externalizing problems, nor to changes in externalizing problems, anxiety, and depression. Additionally, more sibling conflict was related to a higher starting level of and faster decreases in problem behaviors. Our results support the ethnic equivalence model, which holds that the influence of family relationships is similar for different ethnic groups. Moreover, sibling support and conflict affect both the level and the fluctuations in problem behavior over time in specific ethnic groups similarly. Implications for future studies and interventions are subsequently discussed.

Similarity or difference?

DEFF Research Database (Denmark)

Villadsen, Anders Ryom

2013-01-01

While the organizational structures and strategies of public organizations have attracted substantial research attention among public management scholars, little research has explored how these organizational core dimensions are interconnected and influenced by pressures for similarity....... In this paper I address this topic by exploring the relation between expenditure strategy isomorphism and structure isomorphism in Danish municipalities. Different literatures suggest that organizations exist in concurrent pressures for being similar to and different from other organizations in their field......-shaped relation exists between expenditure strategy isomorphism and structure isomorphism in a longitudinal quantitative study of Danish municipalities....

The classical Stefan problem basic concepts, modelling and analysis

CERN Document Server

Gupta, SC

2003-01-01

This volume emphasises studies related toclassical Stefan problems. The term "Stefan problem" isgenerally used for heat transfer problems with phase-changes suchas from the liquid to the solid. Stefan problems have somecharacteristics that are typical of them, but certain problemsarising in fields such as mathematical physics and engineeringalso exhibit characteristics similar to them. The term``classical" distinguishes the formulation of these problems fromtheir weak formulation, in which the solution need not possessclassical derivatives. Under suitable assumptions, a weak solutioncould be as good as a classical solution. In hyperbolic Stefanproblems, the characteristic features of Stefan problems arepresent but unlike in Stefan problems, discontinuous solutions areallowed because of the hyperbolic nature of the heat equation. Thenumerical solutions of inverse Stefan problems, and the analysis ofdirect Stefan problems are so integrated that it is difficult todiscuss one without referring to the other. So no...

Emotional autonomy and problem behavior among Chinese adolescents.

Science.gov (United States)

Chou, Kee-Lee

2003-12-01

The author examined the association between emotional autonomy and problem behavior among Chinese adolescents living in Hong Kong. The respondents were 512 adolescents, 16 to 18 years of age, who were interviewed for a cross-sectional study. Three dimensions of emotional autonomy including individuation, nondependency on parents, and de-idealization of parents were significantly and positively correlated with the amount of problem behavior the participants engaged in during the past 6 months. Using a simple linear multiple regression model, the author found that problem behavior was associated with only one aspect of emotional autonomy-individuation. Results indicated that the relationship between problem behavior and three aspects of emotional autonomy was similar in both individualistic and collectivistic societies.

Genetic and environmental influences on externalizing behavior and alcohol problems in adolescence: A female twin study

Science.gov (United States)

Knopik, Valerie S.; Heath, Andrew C.; Bucholz, Kathleen K.; Madden, Pamela A.F.; Waldron, Mary

2009-01-01

Genetic and environmental contributions to the observed correlations among DSM-IV ADHD problems [inattentive (INATT) and hyperactive/impulsive (HYP/IMP) behaviors], conduct problems (CDP) and alcohol problems (AlcProb) were examined by fitting multivariate structural equation models to data from the Missouri Adolescent Female Twin Study [N=2892 twins (831 monozygotic pairs, 615 dizygotic pairs)]. Based on results of preliminary regression models, we modified the structural model to jointly estimate (i) the regression of each phenotype on significant familial/prenatal predictors, and (ii) genetic and environmental contributions to the residual variance and covariance. Results suggested that (i) parental risk factors, such as parental alcohol dependence and regular smoking, increase risk for externalizing behavior; (ii) prenatal exposures predicted increased symptomatology for HYP/IMP (smoking during pregnancy), INATT and CDP (prenatal alcohol exposure); (iii) after adjusting for measured familial/prenatal risk factors, genetic influences were significant for HYP/IMP, INATT, and CDP; however, similar to earlier reports, genetic effects on alcohol dependence symptoms were negligible; and (iv) in adolescence, correlated liabilities for conduct and alcohol problems are found in environmental factors common to both phenotypes, while covariation among impulsivity, inattention, and conduct problems is primarily due to genetic influences common to these three behaviors. Thus, while a variety of adolescent problem behaviors are significantly correlated, the structure of that association may differ as a function of phenotype (e.g., comorbid HYP/IMP and CDP vs. comorbid CDP and AlcProb), a finding that could inform different approaches to treatment and prevention. PMID:19341765

Does Problem-Based Learning Improve Problem Solving Skills?--A Study among Business Undergraduates at Malaysian Premier Technical University

Science.gov (United States)

Kadir, Z. Abdul; Abdullah, N. H.; Anthony, E.; Salleh, B. Mohd; Kamarulzaman, R.

2016-01-01

Problem-based Learning (PBL) approach has been widely used in various disciplines since it is claimed to improve students' soft skills. However, empirical supports on the effect of PBL on problem solving skills have been lacking and anecdotal in nature. This study aimed to determine the effect of PBL approach on students' problem solving skills…

Effective Summation and Interpolation of Series by Self-Similar Root Approximants

Directory of Open Access Journals (Sweden)

Simon Gluzman

2015-06-01

Full Text Available We describe a simple analytical method for effective summation of series, including divergent series. The method is based on self-similar approximation theory resulting in self-similar root approximants. The method is shown to be general and applicable to different problems, as is illustrated by a number of examples. The accuracy of the method is not worse, and in many cases better, than that of Padé approximants, when the latter can be defined.

Using Categorization of Problems as an Instructional Tool to Help Introductory Students Learn Physics

Science.gov (United States)

Mason, Andrew; Singh, Chandralekha

2016-01-01

The ability to categorize problems based upon underlying principles, rather than contexts, is considered a hallmark of expertise in physics problem solving. With inspiration from a classic study by Chi, Feltovich, and Glaser, we compared the categorization of 25 introductory mechanics problems based upon similarity of solution by students in large…

One dimensional beam. Asymptotic and self similar solutions

International Nuclear Information System (INIS)

Feix, M.R.; Duranceau, J.L.; Besnard, D.

1982-06-01

Rescaling transformations provide a useful tool to solve nonlinear problems described by partial derivative equations. A brief review of this method is presented together with the connection with the self similar solutions obtained by compacting the independent variable with one of them (the time). The general theory is reported through examples found in Plasma Physics with a careful distinction between systems described by Hamiltonian and others where irreversible phenomena, like diffusion, are taken into account

Problem-solving ability and repetition of deliberate self-harm: a multicentre study.

Science.gov (United States)

McAuliffe, Carmel; Corcoran, Paul; Keeley, Helen S; Arensman, Ella; Bille-Brahe, Unni; De Leo, Diego; Fekete, Sandor; Hawton, Keith; Hjelmeland, Heidi; Kelleher, Margaret; Kerkhof, Ad J F M; Lönnqvist, Jouko; Michel, Konrad; Salander-Renberg, Ellinor; Schmidtke, Armin; Van Heeringen, Kees; Wasserman, Danuta

2006-01-01

While recent studies have found problem-solving impairments in individuals who engage in deliberate self-harm (DSH), few studies have examined repeaters and non-repeaters separately. The aim of the present study was to investigate whether specific types of problem-solving are associated with repeated DSH. As part of the WHO/EURO Multicentre Study on Suicidal Behaviour, 836 medically treated DSH patients (59% repeaters) from 12 European regions were interviewed using the European Parasuicide Study Interview Schedule (EPSIS II) approximately 1 year after their index episode. The Utrecht Coping List (UCL) assessed habitual responses to problems. Factor analysis identified five dimensions--Active Handling, Passive-Avoidance, Problem Sharing, Palliative Reactions and Negative Expression. Passive-Avoidance--characterized by a pre-occupation with problems, feeling unable to do anything, worrying about the past and taking a gloomy view of the situation, a greater likelihood of giving in so as to avoid difficult situations, the tendency to resign oneself to the situation, and to try to avoid problems--was the problem-solving dimension most strongly associated with repetition, although this association was attenuated by self-esteem. The outcomes of the study indicate that treatments for DSH patients with repeated episodes should include problem-solving interventions. The observed passivity and avoidance of problems (coupled with low self-esteem) associated with repetition suggests that intensive therapeutic input and follow-up are required for those with repeated DSH.

Problems Faced by Beginning Teachers in Private Elementary Schools: A Comparative Study between Spain and Mexico

Directory of Open Access Journals (Sweden)

Magda Yolanda Cantú Tijerina

2006-11-01

Full Text Available In order to explore the problems faced by beginning teachers in private elementary schools in the Spanish city of Madrid and in the Mexican city of Monterrey, questionnaires were applied to private school teachers just starting out in both cities. The results indicate that in both contexts, as beginners, teachers face problems of an academic, organizational, social, and material and technological nature. However, it stresses the fact that Mexican teachers perceive more problems in all the categories than do their Spanish colleagues. Similarity in the results was found in the category of social problems, which was the one mentioned least by the teachers in both cities. This suggests that the cultural nature of these two countries may be a factor to be considered in connection with fostering beginning teachers’ adaptation process.

Safety of pressurized water reactors: problems and corresponding studies

International Nuclear Information System (INIS)

Cogne, F.

1976-01-01

The author recalls the safety problems subject to researches in the CEA, either because of their importance or because studies made abroad were not sufficiently developed or were classified or in order to acquire an independent judgement when safety is concerned. Those problems and studies are submitted referring to the 3 existing shields between man and dangerous materials: fuel element can, thermal shield, (pressure vessel and pipes), biological shield of which the behaviour is studied in connection with outside aggressions such as earthquakes, plane crashes, chemical explosions.. [fr

Emerging quasi-0D states at vanishing total entropy of the 1D hard sphere system: A coarse-grained similarity to the car parking problem

Science.gov (United States)

Frusawa, Hiroshi

2014-05-01

A coarse-grained system of one-dimensional (1D) hard spheres (HSs) is created using the Delaunay tessellation, which enables one to define the quasi-0D state. It is found from comparing the quasi-0D and 1D free energy densities that a frozen state due to the emergence of quasi-0D HSs is thermodynamically more favorable than fluidity with a large-scale heterogeneity above crossover volume fraction of ϕc=e/(1+e)=0.731⋯ , at which the total entropy of the 1D state vanishes. The Delaunay-based lattice mapping further provides a similarity between the dense HS system above ϕc and the jamming limit in the car parking problem.

Emerging quasi-0D states at vanishing total entropy of the 1D hard sphere system: A coarse-grained similarity to the car parking problem

International Nuclear Information System (INIS)

Frusawa, Hiroshi

2014-01-01

A coarse-grained system of one-dimensional (1D) hard spheres (HSs) is created using the Delaunay tessellation, which enables one to define the quasi-0D state. It is found from comparing the quasi-0D and 1D free energy densities that a frozen state due to the emergence of quasi-0D HSs is thermodynamically more favorable than fluidity with a large-scale heterogeneity above crossover volume fraction of ϕ c =e/(1+e)=0.731⋯ , at which the total entropy of the 1D state vanishes. The Delaunay-based lattice mapping further provides a similarity between the dense HS system above ϕ c and the jamming limit in the car parking problem.

Studies in nonlinear problems of energy

Energy Technology Data Exchange (ETDEWEB)

Matkowsky, B.J.

1992-07-01

Emphasis has been on combustion and flame propagation. The research program was on modeling, analysis and computation of combustion phenomena, with emphasis on transition from laminar to turbulent combustion. Nonlinear dynamics and pattern formation were investigated in the transition. Stability of combustion waves, and transitions to complex waves are described. Combustion waves possess large activation energies, so that chemical reactions are significant only in thin layers, or reaction zones. In limit of infinite activation energy, the zones shrink to moving surfaces, (fronts) which must be found during the analysis, so that (moving free boundary problems). The studies are carried out for limiting case with fronts, while the numerical studies are carried out for finite, though large, activation energy. Accurate resolution of the solution in the reaction zones is essential, otherwise false predictions of dynamics are possible. Since the the reaction zones move, adaptive pseudo-spectral methods were developed. The approach is based on a synergism of analytical and computational methods. The numerical computations build on and extend the analytical information. Furthermore, analytical solutions serve as benchmarks for testing the accuracy of the computation. Finally, ideas from analysis (singular perturbation theory) have induced new approaches to computations. The computational results suggest new analysis to be considered. Among the recent interesting results, was spatio-temporal chaos in combustion. One goal is extension of the adaptive pseudo-spectral methods to adaptive domain decomposition methods. Efforts have begun to develop such methods for problems with multiple reaction zones, corresponding to problems with more complex, and more realistic chemistry. Other topics included stochastics, oscillators, Rysteretic Josephson junctions, DC SQUID, Markov jumps, laser with saturable absorber, chemical physics, Brownian movement, combustion synthesis, etc.

Severity of eczema and mental health problems in Japanese schoolchildren: The ToMMo Child Health Study.

Science.gov (United States)

Kuniyoshi, Yasutaka; Kikuya, Masahiro; Miyashita, Masako; Yamanaka, Chizuru; Ishikuro, Mami; Obara, Taku; Metoki, Hirohito; Nakaya, Naoki; Nagami, Fuji; Tomita, Hiroaki; Hozawa, Atsushi; Tsuji, Ichiro; Kure, Shigeo; Yaegashi, Nobuo; Yamamoto, Masayuki; Kuriyama, Shinichi

2018-04-13

The association between eczema and mental health problems in schoolchildren has been underexplored. We aimed to investigate this association with the validated questionnaires. Of 46,648 invited children, we analyzed 9954 (21.3%) in the 2nd to the 8th grades from the ToMMo Child Health Study conducted in 2014 and 2015, a cross-sectional survey in Miyagi Prefecture, Japan. We defined eczema status as "normal," "mild/moderate," or "severe," based on the presence of persistent flexural eczema and sleep disturbance, according to the International Study of Asthma and Allergies in Childhood (ISAAC) Eczema Symptom Questionnaire. Clinical ranges of Strengths and Difficulties Questionnaire (SDQ) total difficulties scores and four SDQ subcategories of emotional symptoms, conduct problems, hyperactivity/inattention, and peer problems were defined as scores ≥16, ≥5, ≥5, ≥7, and ≥5, respectively. The mean SDQ total difficulties score significantly increased as eczema status worsened (all P ≤ 0.004 for trend). The OR of scores in the clinical range for SDQ total difficulties were 1.51 (95% CI, 1.31-1.74) for mild/moderate eczema and 2.63 (95% CI, 1.91-3.63) for severe eczema (P eczema as a reference. The association between severity of eczema and four SDQ subcategories showed a similar trend (all P ≤ 0.017 for trend). We found a significant association between severity of eczema and mental health problems. The presence of eczema was associated with four SDQ subcategories. Copyright © 2018 Japanese Society of Allergology. Production and hosting by Elsevier B.V. All rights reserved.

Patient Similarity in Prediction Models Based on Health Data: A Scoping Review

Science.gov (United States)

Sharafoddini, Anis; Dubin, Joel A

2017-01-01

Background Physicians and health policy makers are required to make predictions during their decision making in various medical problems. Many advances have been made in predictive modeling toward outcome prediction, but these innovations target an average patient and are insufficiently adjustable for individual patients. One developing idea in this field is individualized predictive analytics based on patient similarity. The goal of this approach is to identify patients who are similar to an index patient and derive insights from the records of similar patients to provide personalized predictions.. Objective The aim is to summarize and review published studies describing computer-based approaches for predicting patients’ future health status based on health data and patient similarity, identify gaps, and provide a starting point for related future research. Methods The method involved (1) conducting the review by performing automated searches in Scopus, PubMed, and ISI Web of Science, selecting relevant studies by first screening titles and abstracts then analyzing full-texts, and (2) documenting by extracting publication details and information on context, predictors, missing data, modeling algorithm, outcome, and evaluation methods into a matrix table, synthesizing data, and reporting results. Results After duplicate removal, 1339 articles were screened in abstracts and titles and 67 were selected for full-text review. In total, 22 articles met the inclusion criteria. Within included articles, hospitals were the main source of data (n=10). Cardiovascular disease (n=7) and diabetes (n=4) were the dominant patient diseases. Most studies (n=18) used neighborhood-based approaches in devising prediction models. Two studies showed that patient similarity-based modeling outperformed population-based predictive methods. Conclusions Interest in patient similarity-based predictive modeling for diagnosis and prognosis has been growing. In addition to raw/coded health

Problems of Togetherness and Similarity of Shakarim Kudayberdiyev and L.N. Tolstoy’s Works

Directory of Open Access Journals (Sweden)

Sagymbay Zhumagulov

2013-01-01

Full Text Available The article presents the comparative analysis of oeuvre of two great representatives of Russian and Kazakh nations – Lev Nikolayevich Tolstoy and Shakarim Kudayberdiyev. Authors of article find the common features of thinkers’ talent and spirit, emphasize some facts of their lives and oeuvres. Having generalized everything told about unity and similarity of writers’ oeuvres, authors found common features in their lives, which catalyzed the eternal fight of humanism against sinister

Study on the mechanism and efficiency of simulated annealing using an LP optimization benchmark problem - 113

International Nuclear Information System (INIS)

Qianqian, Li; Xiaofeng, Jiang; Shaohong, Zhang

2010-01-01

Simulated Annealing Algorithm (SAA) for solving combinatorial optimization problems is a popular method for loading pattern optimization. The main purpose of this paper is to understand the underlying search mechanism of SAA and to study its efficiency. In this study, a general SAA that employs random pair exchange of fuel assemblies to search for the optimum fuel Loading Pattern (LP) is applied to an exhaustively searched LP optimization benchmark problem. All the possible LPs of the benchmark problem have been enumerated and evaluated via the use of the very fast and accurate Hybrid Harmonics and Linear Perturbation (HHLP) method, such that the mechanism of SA for LP optimization can be explicitly analyzed and its search efficiency evaluated. The generic core geometry itself dictates that only a small number LPs can be generated by performing random single pair exchanges and that the LPs are necessarily mostly similar to the initial LP. This phase space effect turns out to be the basic mechanism in SAA that can explain its efficiency and good local search ability. A measure of search efficiency is introduced which shows that the stochastic nature of SAA greatly influences the variability of its search efficiency. It is also found that using fuel assembly k-infinity distribution as a technique to filter the LPs can significantly enhance the SAA search efficiency. (authors)

MetrIntSimil—An Accurate and Robust Metric for Comparison of Similarity in Intelligence of Any Number of Cooperative Multiagent Systems

Directory of Open Access Journals (Sweden)

Laszlo Barna Iantovics

2018-02-01

Full Text Available Intelligent cooperative multiagent systems are applied for solving a large range of real-life problems, including in domains like biology and healthcare. There are very few metrics able to make an effective measure of the machine intelligence quotient. The most important drawbacks of the designed metrics presented in the scientific literature consist in the limitation in universality, accuracy, and robustness. In this paper, we propose a novel universal metric called MetrIntSimil capable of making an accurate and robust symmetric comparison of the similarity in intelligence of any number of cooperative multiagent systems specialized in difficult problem solving. The universality is an important necessary property based on the large variety of designed intelligent systems. MetrIntSimil makes a comparison by taking into consideration the variability in intelligence in the problem solving of the compared cooperative multiagent systems. It allows a classification of the cooperative multiagent systems based on their similarity in intelligence. A cooperative multiagent system has variability in the problem solving intelligence, and it can manifest lower or higher intelligence in different problem solving tasks. More cooperative multiagent systems with similar intelligence can be included in the same class. For the evaluation of the proposed metric, we conducted a case study for more intelligent cooperative multiagent systems composed of simple computing agents applied for solving the Symmetric Travelling Salesman Problem (STSP that is a class of NP-hard problems. STSP is the problem of finding the shortest Hamiltonian cycle/tour in a weighted undirected graph that does not have loops or multiple edges. The distance between two cities is the same in each opposite direction. Two classes of similar intelligence denoted IntClassA and IntClassB were identified. The experimental results show that the agent belonging to IntClassA intelligence class is less

Thai Language Sentence Similarity Computation Based on Syntactic Structure and Semantic Vector

Science.gov (United States)

Wang, Hongbin; Feng, Yinhan; Cheng, Liang

2018-03-01

Sentence similarity computation plays an increasingly important role in text mining, Web page retrieval, machine translation, speech recognition and question answering systems. Thai language as a kind of resources scarce language, it is not like Chinese language with HowNet and CiLin resources. So the Thai sentence similarity research faces some challenges. In order to solve this problem of the Thai language sentence similarity computation. This paper proposes a novel method to compute the similarity of Thai language sentence based on syntactic structure and semantic vector. This method firstly uses the Part-of-Speech (POS) dependency to calculate two sentences syntactic structure similarity, and then through the word vector to calculate two sentences semantic similarity. Finally, we combine the two methods to calculate two Thai language sentences similarity. The proposed method not only considers semantic, but also considers the sentence syntactic structure. The experiment result shows that this method in Thai language sentence similarity computation is feasible.

Facilitating case reuse during problem solving in algebra-based physics

Science.gov (United States)

Mateycik, Frances Ann

This research project investigates students' development of problem solving schemata while using strategies that facilitate the process of using solved examples to assist with a new problem (case reuse). Focus group learning interviews were used to explore students' perceptions and understanding of several problem solving strategies. Individual clinical interviews were conducted and quantitative examination data were collected to assess students' conceptual understanding, knowledge organization, and problem solving performance on a variety of problem tasks. The study began with a short one-time treatment of two independent, research-based strategies chosen to facilitate case reuse. Exploration of students' perceptions and use of the strategies lead investigators to select one of the two strategies to be implemented over a full semester of focus group interviews. The strategy chosen was structure mapping. Structure maps are defined as visual representations of quantities and their associations. They were created by experts to model the appropriate mental organization of knowledge elements for a given physical concept. Students were asked to use these maps as they were comfortable while problem solving. Data obtained from this phase of our study (Phase I) offered no evidence of improved problem solving schema. The 11 contact hour study was barely sufficient time for students to become comfortable using the maps. A set of simpler strategies were selected for their more explicit facilitation of analogical reasoning, and were used together during two more semester long focus group treatments (Phase II and Phase III of this study). These strategies included the use of a step-by-step process aimed at reducing cognitive load associated with mathematical procedure, direct reflection of principles involved in a given set of problems, and the direct comparison of problem pairs designed to be void of surface similarities (similar objects or object orientations) and sharing

Self-similar Lagrangian hydrodynamics of beam-heated solar flare atmospheres

International Nuclear Information System (INIS)

Brown, J.C.; Emslie, A.G.

1989-01-01

The one-dimensional hydrodynamic problem in Lagrangian coordinates (Y, t) is considered for which the specific energy input Q has a power-law dependence on both Y and t, and the initial density distribution is rho(0) which is directly proportional to Y exp gamma. In regimes where the contributions of radiation, conduction, quiescent heating, and gravitational terms in the energy equation are negligible compared to those arising from Q, the problem has a self-similar solution, with the hydrodynamic variables depending only on a single independent variable which is a combination of Y, t, and the dimensional constants of the problem. It is then shown that the problem of solar flare chromospheric heating due to collisional interaction of a beam of electrons (or protons) with a power-law energy spectrum can be approximated by such forms of Q(Y, t) and rho(0)(Y), and that other terms are negligible compared to Q over a restricted regime early in the flare. 29 refs

The Relationships of Problem Solving Styles to Parenting Styles: Two Studies

Science.gov (United States)

Neyen, Julia; Volpe, Carolyn Ann; Selby, Edwin C.; Houtz, John C.

2017-01-01

Two independent studies were conducted to examine the relationship of problem solving styles to parenting styles. Both studies used VIEW: An Assessment of Problem Solving Style and the Parental Authority Questionnaire (PAQ). Study 1 included 173 adults recruited using Mechanical Turk and Study 2 included 131 adults recruited using Qualtrics. Data…

VET workers problem-solving skills in technology-rich environments: European approach

OpenAIRE

Hämäläinen, Raija

2014-01-01

The European workplace is challenging VET adults problem-solving skills in technology-rich environments (TREs). So far, no international large-scale assessment data has been available for VET. The PIAAC data comprise the most comprehensive source of information on adults skills to date. The present study (N=50 369) focuses on gaining insight into the problem-solving skills in TREs of adults with a VET background. When examining the similarities and differences in VET adults problem-solving sk...

VET workers’ problem-solving skills in technology-rich environments: European approach

OpenAIRE

Hämäläinen, Raija; Cincinnato, Sebastiano; Malin, Antero; De Wever, Bram

2014-01-01

The European workplace is challenging VET adults’ problem-solving skills in technology-rich environments (TREs). So far, no international large-scale assessment data has been available for VET. The PIAAC data comprise the most comprehensive source of information on adults’ skills to date. The present study (N=50 369) focuses on gaining insight into the problem-solving skills in TREs of adults with a VET background. When examining the similarities and differences in VET adults’ problem-solving...

Problem-solving skills training for mothers of children recently diagnosed with autism spectrum disorder: A pilot feasibility study.

Science.gov (United States)

Nguyen, Cathina T; Fairclough, Diane L; Noll, Robert B

2016-01-01

Problem-solving skills training is an intervention designed to teach coping skills that has shown to decrease negative affectivity (depressive symptoms, negative mood, and post-traumatic stress symptoms) in mothers of children with cancer. The objective of this study was to see whether mothers of children recently diagnosed with autism spectrum disorder would be receptive to receiving problem-solving skills training (feasibility trial). Participants were recruited from a local outpatient developmental clinic that is part of a university department of pediatrics. Participants were to receive eight 1-h sessions of problem-solving skills training and were asked to complete assessments prior to beginning problem-solving skills training (T1), immediately after intervention (T2), and 3 months after T2 (T3). Outcome measures assessed problem-solving skills and negative affectivity (i.e. distress). In total, 30 mothers were approached and 24 agreed to participate (80.0%). Of them, 17 mothers completed problem-solving skills training (retention rate: 70.8%). Mothers of children with autism spectrum disorder who completed problem-solving skills training had significant decreases in negative affectivity and increases in problem-solving skills. A comparison to mothers of children with cancer shows that mothers of children with autism spectrum disorder displayed similar levels of depressive symptoms but less negative mood and fewer symptoms of post-traumatic stress. Data suggest that problem-solving skills training may be an effective way to alleviate distress in mothers of children recently diagnosed with autism spectrum disorder. Data also suggest that mothers of children with autism spectrum disorder were moderately receptive to receiving problem-solving skills training. Implications are that problem-solving skills training may be beneficial to parents of children with autism spectrum disorder; modifications to improve retention rates are suggested. © The Author(s) 2015.

SimilarityExplorer: A visual inter-comparison tool for multifaceted climate data

Science.gov (United States)

J. Poco; A. Dasgupta; Y. Wei; W. Hargrove; C. Schwalm; R. Cook; E. Bertini; C. Silva

2014-01-01

Inter-comparison and similarity analysis to gauge consensus among multiple simulation models is a critical visualization problem for understanding climate change patterns. Climate models, specifically, Terrestrial Biosphere Models (TBM) represent time and space variable ecosystem processes, for example, simulations of photosynthesis and respiration, using algorithms...

BSSF: a fingerprint based ultrafast binding site similarity search and function analysis server

Directory of Open Access Journals (Sweden)

Jiang Hualiang

2010-01-01

Full Text Available Abstract Background Genome sequencing and post-genomics projects such as structural genomics are extending the frontier of the study of sequence-structure-function relationship of genes and their products. Although many sequence/structure-based methods have been devised with the aim of deciphering this delicate relationship, there still remain large gaps in this fundamental problem, which continuously drives researchers to develop novel methods to extract relevant information from sequences and structures and to infer the functions of newly identified genes by genomics technology. Results Here we present an ultrafast method, named BSSF(Binding Site Similarity & Function, which enables researchers to conduct similarity searches in a comprehensive three-dimensional binding site database extracted from PDB structures. This method utilizes a fingerprint representation of the binding site and a validated statistical Z-score function scheme to judge the similarity between the query and database items, even if their similarities are only constrained in a sub-pocket. This fingerprint based similarity measurement was also validated on a known binding site dataset by comparing with geometric hashing, which is a standard 3D similarity method. The comparison clearly demonstrated the utility of this ultrafast method. After conducting the database searching, the hit list is further analyzed to provide basic statistical information about the occurrences of Gene Ontology terms and Enzyme Commission numbers, which may benefit researchers by helping them to design further experiments to study the query proteins. Conclusions This ultrafast web-based system will not only help researchers interested in drug design and structural genomics to identify similar binding sites, but also assist them by providing further analysis of hit list from database searching.

[Investigation of problem solving skills among psychiatric patients].

Science.gov (United States)

Póos, Judit; Annus, Rita; Perczel Forintos, Dóra

2008-01-01

According to our present knowledge depression and hopelessness play an important role in attempted suicide and the development of hopelessness seems to be closely associated with poor problem solving skills. In the present study we have used the internationally well-known MEPS (Means-Ends Problem Solving Test; a measure of social problem solving ability) in Hungary for the first time and combined with other tests. We intended to explore the cognitive risk factors that potentially play a role in the suicidal behavior in clinical population. In our study we compared a group of individuals who had attempted suicide to a nonsuicidal psychiatric control group and a normal control group (61 subjects in each group). Our results confirm the findings of others that psychiatric patients have difficulties in social problem solving compared to normal controls. Moreover, they generate less and poorer solutions. According to our data problem solving skills of the two clinical groups were similar. A strong positive correlation was found between poor problem solving skills, depression and hopelessness which may suggest that the development of problem solving skills could help to reduce negative mood.

Problem gambling among ethnic minorities: results from an epidemiological study

Directory of Open Access Journals (Sweden)

Kyle R. Caler

2017-09-01

Full Text Available Abstract A few studies have examined gambling behavior and problem gambling among minorities and reported higher rates of both participation and gambling problems among particular minority groups in comparison to Whites who gamble. The present study utilized a representative, epidemiological sample of adults in New Jersey to explore gambling behavior, gambling problem severity, substance use, problem behavior, and mental health issues among minorities. Univariate analyses were conducted, comparing Whites (n = 1341 to respondents who identified as Hispanic (n = 394, Black (n = 261, or Asian/other (n = 177. Overall, the highest proportion of Hispanics were high-risk problem gamblers. Hispanic participants were also significantly more likely than other groups to use and abuse substances and to report mental health problems in the past month, behavioral addictions, and/or suicidal ideation in the past year. Primary predictors of White high risk problem gamblers were being young and male with friends or family who gambled, fair to poor health status, substance use, gambling once a week or more both online and in land-based venues, and engaging in a number of gambling activities. In contrast, gender was not a predictor of minority high risk problem gamblers, who were characterized primarily by having friends or family who gambled, gambling online only, having a behavioral addiction and playing instant scratch-offs and gaming machines. Implications for research and practice are discussed.

Automatic Content Creation for Games to Train Students Distinguishing Similar Chinese Characters

Science.gov (United States)

Lai, Kwong-Hung; Leung, Howard; Tang, Jeff K. T.

In learning Chinese, many students often have the problem of mixing up similar characters. This can cause misunderstanding and miscommunication in daily life. It is thus important for students learning the Chinese language to be able to distinguish similar characters and understand their proper usage. In this paper, we propose a game style framework in which the game content in identifying similar Chinese characters in idioms and words is created automatically. Our prior work on analyzing students’ Chinese handwriting can be applied in the similarity measure of Chinese characters. We extend this work by adding the component of radical extraction to speed up the search process. Experimental results show that the proposed method is more accurate and faster in finding more similar Chinese characters compared with the baseline method without considering the radical information.

Some Problems of the Kazakh Drama Study

Directory of Open Access Journals (Sweden)

Sagymbay Zhumagulov

2013-01-01

Full Text Available The article discusses theoretical and literary problems of national drama in the Kazakh literary of 1960s-1980s, analyzes the most significant works, devoted to the study of innovation in the poetry and the drama of the Kazakh system of genres, comprehensively studies literary tradition in scientific and methodological literature and determined its role in the development of the Kazakh drama

A grammar-based semantic similarity algorithm for natural language sentences.

Science.gov (United States)

Lee, Ming Che; Chang, Jia Wei; Hsieh, Tung Cheng

2014-01-01

This paper presents a grammar and semantic corpus based similarity algorithm for natural language sentences. Natural language, in opposition to "artificial language", such as computer programming languages, is the language used by the general public for daily communication. Traditional information retrieval approaches, such as vector models, LSA, HAL, or even the ontology-based approaches that extend to include concept similarity comparison instead of cooccurrence terms/words, may not always determine the perfect matching while there is no obvious relation or concept overlap between two natural language sentences. This paper proposes a sentence similarity algorithm that takes advantage of corpus-based ontology and grammatical rules to overcome the addressed problems. Experiments on two famous benchmarks demonstrate that the proposed algorithm has a significant performance improvement in sentences/short-texts with arbitrary syntax and structure.

Self-Similarity Superresolution for Resource-Constrained Image Sensor Node in Wireless Sensor Networks

Directory of Open Access Journals (Sweden)

Yuehai Wang

2014-01-01

Full Text Available Wireless sensor networks, in combination with image sensors, open up a grand sensing application field. It is a challenging problem to recover a high resolution (HR image from its low resolution (LR counterpart, especially for low-cost resource-constrained image sensors with limited resolution. Sparse representation-based techniques have been developed recently and increasingly to solve this ill-posed inverse problem. Most of these solutions are based on an external dictionary learned from huge image gallery, consequently needing tremendous iteration and long time to match. In this paper, we explore the self-similarity inside the image itself, and propose a new combined self-similarity superresolution (SR solution, with low computation cost and high recover performance. In the self-similarity image super resolution model (SSIR, a small size sparse dictionary is learned from the image itself by the methods such as KSVD. The most similar patch is searched and specially combined during the sparse regulation iteration. Detailed information, such as edge sharpness, is preserved more faithfully and clearly. Experiment results confirm the effectiveness and efficiency of this double self-learning method in the image super resolution.

Formulation of similarity porous media systems

International Nuclear Information System (INIS)

Anderson, R.M.; Ford, W.T.; Ruttan, A.; Strauss, M.J.

1982-01-01

The mathematical formulation of the Porous Media System (PMS) describing two-phase, immiscible, compressible fluid flow in linear, homogeneous porous media is reviewed and expanded. It is shown that families of common vertex, coaxial parabolas and families of parallel lines are the only families of curves on which solutions of the PMS may be constant. A coordinate transformation is used to change the partial differential equations of the PMS to a system of ordinary differential equations, referred to as a similarity Porous Media System (SPMS), in which the independent variable denotes movement from curve to curve in a selected family of curves. Properties of solutions of the first boundary value problem are developed for the SPMS

Density-based similarity measures for content based search

Energy Technology Data Exchange (ETDEWEB)

Hush, Don R [Los Alamos National Laboratory; Porter, Reid B [Los Alamos National Laboratory; Ruggiero, Christy E [Los Alamos National Laboratory

2009-01-01

We consider the query by multiple example problem where the goal is to identify database samples whose content is similar to a coUection of query samples. To assess the similarity we use a relative content density which quantifies the relative concentration of the query distribution to the database distribution. If the database distribution is a mixture of the query distribution and a background distribution then it can be shown that database samples whose relative content density is greater than a particular threshold {rho} are more likely to have been generated by the query distribution than the background distribution. We describe an algorithm for predicting samples with relative content density greater than {rho} that is computationally efficient and possesses strong performance guarantees. We also show empirical results for applications in computer network monitoring and image segmentation.

A remark on some nonlinear elliptic problems

Directory of Open Access Journals (Sweden)

Lucio Boccardo

2002-10-01

Full Text Available We shall prove an existence result of $W_0^{1,p}(Omega$ solutions for the boundary value problem $$displylines{ -mathop{m div} a(x, u,abla u=F quadmbox{in }Omegacr u=0quadmbox{on }partialOmega }$$ with right hand side in $W^{-1,p'}(Omega$. The features of the equation are that no restrictions on the growth of the function $a(x,s,xi$ with respect to $s$ are assumed and that $a(x,s,xi$ with respect to $xi$ is monotone, but not strictly monotone. We overcome the difficulty of the uncontrolled growth of $a$ thanks to a suitable definition of solution (similar to the one introduced in cite{B6} for the study of the Dirichlet problem in $L^1$ and the difficulty of the not strict monotonicity thanks to a technique (the $L^1$-version of Minty's Lemma similar to the one used in cite{BO}.

Similar solutions for viscous hypersonic flow over a slender three-fourths-power body of revolution

Science.gov (United States)

Lin, Chin-Shun

1987-01-01

For hypersonic flow with a shock wave, there is a similar solution consistent throughout the viscous and inviscid layers along a very slender three-fourths-power body of revolution The strong pressure interaction problem can then be treated by the method of similarity. Numerical calculations are performed in the viscous region with the edge pressure distribution known from the inviscid similar solutions. The compressible laminar boundary-layer equations are transformed into a system of ordinary differential equations. The resulting two-point boundary value problem is then solved by the Runge-Kutta method with a modified Newton's method for the corresponding boundary conditions. The effects of wall temperature, mass bleeding, and body transverse curvature are investigated. The induced pressure, displacement thickness, skin friction, and heat transfer due to the previously mentioned parameters are estimated and analyzed.

Student Homicidal Violence in Schools: An International Problem

Science.gov (United States)

Bondu, Rebecca; Cornell, Dewey G.; Scheithauer, Herbert

2011-01-01

School homicides have become a worldwide phenomenon. In the decade following the Columbine shooting there have been at least forty similar events in other countries. This article addresses the international scope of this problem and some of the complex conceptual issues that make student homicidal violence difficult to define and study. Meaningful…

Dynamic similarity in erosional processes

Science.gov (United States)

Scheidegger, A.E.

1963-01-01

A study is made of the dynamic similarity conditions obtaining in a variety of erosional processes. The pertinent equations for each type of process are written in dimensionless form; the similarity conditions can then easily be deduced. The processes treated are: raindrop action, slope evolution and river erosion. ?? 1963 Istituto Geofisico Italiano.

A Grammar-Based Semantic Similarity Algorithm for Natural Language Sentences

Science.gov (United States)

Chang, Jia Wei; Hsieh, Tung Cheng

2014-01-01

This paper presents a grammar and semantic corpus based similarity algorithm for natural language sentences. Natural language, in opposition to “artificial language”, such as computer programming languages, is the language used by the general public for daily communication. Traditional information retrieval approaches, such as vector models, LSA, HAL, or even the ontology-based approaches that extend to include concept similarity comparison instead of cooccurrence terms/words, may not always determine the perfect matching while there is no obvious relation or concept overlap between two natural language sentences. This paper proposes a sentence similarity algorithm that takes advantage of corpus-based ontology and grammatical rules to overcome the addressed problems. Experiments on two famous benchmarks demonstrate that the proposed algorithm has a significant performance improvement in sentences/short-texts with arbitrary syntax and structure. PMID:24982952

A Grammar-Based Semantic Similarity Algorithm for Natural Language Sentences

Directory of Open Access Journals (Sweden)

Ming Che Lee

2014-01-01

Full Text Available This paper presents a grammar and semantic corpus based similarity algorithm for natural language sentences. Natural language, in opposition to “artificial language”, such as computer programming languages, is the language used by the general public for daily communication. Traditional information retrieval approaches, such as vector models, LSA, HAL, or even the ontology-based approaches that extend to include concept similarity comparison instead of cooccurrence terms/words, may not always determine the perfect matching while there is no obvious relation or concept overlap between two natural language sentences. This paper proposes a sentence similarity algorithm that takes advantage of corpus-based ontology and grammatical rules to overcome the addressed problems. Experiments on two famous benchmarks demonstrate that the proposed algorithm has a significant performance improvement in sentences/short-texts with arbitrary syntax and structure.

Blind deconvolution using the similarity of multiscales regularization for infrared spectrum

International Nuclear Information System (INIS)

Huang, Tao; Liu, Hai; Zhang, Zhaoli; Liu, Sanyan; Liu, Tingting; Shen, Xiaoxuan; Zhang, Jianfeng; Zhang, Tianxu

2015-01-01

Band overlap and random noise exist widely when the spectra are captured using an infrared spectrometer, especially since the aging of instruments has become a serious problem. In this paper, via introducing the similarity of multiscales, a blind spectral deconvolution method is proposed. Considering that there is a similarity between latent spectra at different scales, it is used as prior knowledge to constrain the estimated latent spectrum similar to pre-scale to reduce artifacts which are produced from deconvolution. The experimental results indicate that the proposed method is able to obtain a better performance than state-of-the-art methods, and to obtain satisfying deconvolution results with fewer artifacts. The recovered infrared spectra can easily extract the spectral features and recognize unknown objects. (paper)

Automated problem list generation and physicians perspective from a pilot study.

Science.gov (United States)

Devarakonda, Murthy V; Mehta, Neil; Tsou, Ching-Huei; Liang, Jennifer J; Nowacki, Amy S; Jelovsek, John Eric

2017-09-01

An accurate, comprehensive and up-to-date problem list can help clinicians provide patient-centered care. Unfortunately, problem lists created and maintained in electronic health records by providers tend to be inaccurate, duplicative and out of date. With advances in machine learning and natural language processing, it is possible to automatically generate a problem list from the data in the EHR and keep it current. In this paper, we describe an automated problem list generation method and report on insights from a pilot study of physicians' assessment of the generated problem lists compared to existing providers-curated problem lists in an institution's EHR system. The natural language processing and machine learning-based Watson 1 method models clinical thinking in identifying a patient's problem list using clinical notes and structured data. This pilot study assessed the Watson method and included 15 randomly selected, de-identified patient records from a large healthcare system that were each planned to be reviewed by at least two internal medicine physicians. The physicians created their own problem lists, and then evaluated the overall usefulness of their own problem lists (P), Watson generated problem lists (W), and the existing EHR problem lists (E) on a 10-point scale. The primary outcome was pairwise comparisons of P, W, and E. Six out of the 10 invited physicians completed 27 assessments of P, W, and E, and in process evaluated 732 Watson generated problems and 444 problems in the EHR system. As expected, physicians rated their own lists, P, highest. However, W was rated higher than E. Among 89% of assessments, Watson identified at least one important problem that physicians missed. Cognitive computing systems like this Watson system hold the potential for accurate, problem-list-centered summarization of patient records, potentially leading to increased efficiency, better clinical decision support, and improved quality of patient care. Copyright © 2017

Problem neurology residents: a national survey.

Science.gov (United States)

Tabby, David S; Majeed, Muhammed H; Schwartzman, Robert J

2011-06-14

Problem residents are found across most medical specialties at a prevalence of about 10%. This study was designed to explore the prevalence and causes of problem neurology residents and to compare neurology programs' responses and outcomes. Directors of 126 US neurology residency programs were sent an electronic survey. We collected data on demographics, first and all "identifiers" of problem residents, and year of training in which the problem was found. We asked about observable signs, etiology, and who performed remediation. We asked what resources were used and what outcomes occurred. Ninety-five program directors completed surveys (75% response rate). Almost all neurology programs have problem residents (81%). Age, sex, marital status, being a US native, or attending a US medical school had no effect on problem status. Being a parent carried a lower likelihood of problems (32%). Most commonly the problem is acted on during the first year of training. Faculty members without defined educational roles were the most frequent first identifiers. Program directors were the most common remediators. The most common remediation techniques were increasing supervision and assigning a faculty mentor. Graduate medical education office and psychiatric or psychological counseling services were most often used. Eleven percent of problem residents required a program for impaired physicians and 14% required a leave of absence. Sixteen percent were dismissed from their programs. The prevalence of problem residents in neurology is similar to other disciplines, and various resources are available to remediate them.

Comparative Study on Water Impact Problem

OpenAIRE

Yang, Liang; Yang, Hao; Yan, Shiqiang; Ma, Qingwei; Bihnam, Maria

2016-01-01

This paper presents a comparative numerical study for the water impact problems due to dropping of triangular wedges or ship sections. In the numerical investigation, both the dynamic mesh technique and immersed boundary method adopting fixed Cartesian grids have been adopted in order to conform to the motion of the structure. For the former, a multiple-phase solver with the volume of fluid for identifying the free surface is implemented. In the simulation using this method, both the compress...

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

Phenomenological 'Verstehen' and interactionist 'sympathetic understanding': similarities and differences

OpenAIRE

Verhoeven, Jef

1991-01-01

Herbert Blumer, albeit accepting some similarities, did see clear differences between "symbolic interactionism" and "phenomenology". His main criticisms concerned the introspection of phenomenology and consequently the solipsism of this approach. Unfortunately, there was no opportunity in this interview to go into this problem more thoroughly. I want to resume this discussion here. As far as I have been abie to determine, the topic has not yet been treated in detail elsewhere. There has been ...

Improvement of training set structure in fusion data cleaning using Time-Domain Global Similarity method

International Nuclear Information System (INIS)

Liu, J.; Lan, T.; Qin, H.

2017-01-01

Traditional data cleaning identifies dirty data by classifying original data sequences, which is a class-imbalanced problem since the proportion of incorrect data is much less than the proportion of correct ones for most diagnostic systems in Magnetic Confinement Fusion (MCF) devices. When using machine learning algorithms to classify diagnostic data based on class-imbalanced training set, most classifiers are biased towards the major class and show very poor classification rates on the minor class. By transforming the direct classification problem about original data sequences into a classification problem about the physical similarity between data sequences, the class-balanced effect of Time-Domain Global Similarity (TDGS) method on training set structure is investigated in this paper. Meanwhile, the impact of improved training set structure on data cleaning performance of TDGS method is demonstrated with an application example in EAST POlarimetry-INTerferometry (POINT) system.

Being similar while judging right and wrong: The effects of personal and situational similarity on moral judgements.

Science.gov (United States)

Pascal, Emilia

2017-07-20

This study investigated the effects of similarity with the transgressor and the victim on the perceived immorality of the transgression. Participants read two stories describing a person that cheated on their partner and a police officer that mistreated somebody. In the first story we manipulated participants' personal similarity to the transgressor and in the second their personal similarity to the victim. In each story, participants' past situational similarity to the target character was assessed according to their previous experiences of being in the same position. Results show that both personal and past situational similarity to the transgressor determine less severe moral judgements, while personal and past situational similarity with the victim have the opposite effect. We also tested several potential mediators of these effects, derived from competing theoretical accounts of the influence of similarity on perceived responsibility. Empathy emerged as mediating most of the effects of similarity on moral judgements, except those induced by past situational similarity with the victim. The foreseen probability of being in a similar situation mediated only the effects of similarity to the transgressor, and not those of similarity to the victim. Overall, results highlight the complex mechanisms of the influences of similarity on moral judgements. © 2017 International Union of Psychological Science.

Haplotyping Problem, A Clustering Approach

International Nuclear Information System (INIS)

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

2007-01-01

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

Study of Sleep Habits and Sleep Problems Among Medical Students ...

African Journals Online (AJOL)

Background: Good quality sleep and adequate amount of sleep are important in order to have better cognitive performance and avoid health problems and psychiatric disorders. Aim: The aim of this study was to describe sleep habits and sleep problems in a population of undergraduates, interns and postgraduate students ...

A vertex similarity index for better personalized recommendation

Science.gov (United States)

Chen, Ling-Jiao; Zhang, Zi-Ke; Liu, Jin-Hu; Gao, Jian; Zhou, Tao

2017-01-01

Recommender systems benefit us in tackling the problem of information overload by predicting our potential choices among diverse niche objects. So far, a variety of personalized recommendation algorithms have been proposed and most of them are based on similarities, such as collaborative filtering and mass diffusion. Here, we propose a novel vertex similarity index named CosRA, which combines advantages of both the cosine index and the resource-allocation (RA) index. By applying the CosRA index to real recommender systems including MovieLens, Netflix and RYM, we show that the CosRA-based method has better performance in accuracy, diversity and novelty than some benchmark methods. Moreover, the CosRA index is free of parameters, which is a significant advantage in real applications. Further experiments show that the introduction of two turnable parameters cannot remarkably improve the overall performance of the CosRA index.

A lower bound for the node, edge, and arc routing problem

DEFF Research Database (Denmark)

Bach, Lukas; Hasle, Geir; Wøhlk, Sanne

2013-01-01

The Node, Edge, and Arc Routing Problem (NEARP) was defined by Prins and Bouchenoua in 2004, although similar problems have been studied before. This problem, also called the Mixed Capacitated General Routing Problem (MCGRP), generalizes the classical Capacitated Vehicle Routing Problem (CVRP......), the Capacitated Arc Routing Problem (CARP), and the General Routing Problem. It captures important aspects of real-life routing problems that were not adequately modeled in previous Vehicle Routing Problem (VRP) variants. The authors also proposed a memetic algorithm procedure and defined a set of test instances...... called the CBMix benchmark. The NEARP definition and investigation contribute to the development of rich VRPs. In this paper we present the first lower bound procedure for the NEARP. It is a further development of lower bounds for the CARP. We also define two novel sets of test instances to complement...

NONSTANDARD PROBLEMS IN STUDYING THE PROPERTIES FUNCTIONS.

Directory of Open Access Journals (Sweden)

V. I. Kuzmich

2010-06-01

Full Text Available In this paper we consider two non-standard problems that may be offered to students for independent solution in the study of fundamental properties of functions in the course of mathematical analysis. These tasks are wearing creativity and contribute to a better understanding of students to concepts such as monotonicity and continuity of the function.

Finding p-Hub Median Locations: An Empirical Study on Problems and Solution Techniques

Directory of Open Access Journals (Sweden)

Xiaoqian Sun

2017-01-01

Full Text Available Hub location problems have been studied by many researchers for almost 30 years, and, accordingly, various solution methods have been proposed. In this paper, we implement and evaluate several widely used methods for solving five standard hub location problems. To assess the scalability and solution qualities of these methods, three well-known datasets are used as case studies: Turkish Postal System, Australia Post, and Civil Aeronautics Board. Classical problems in small networks can be solved efficiently using CPLEX because of their low complexity. Genetic algorithms perform well for solving three types of single allocation problems, since the problem formulations can be neatly encoded with chromosomes of reasonable size. Lagrangian relaxation is the only technique that solves reliable multiple allocation problems in large networks. We believe that our work helps other researchers to get an overview on the best solution techniques for the problems investigated in our study and also stipulates further interest on cross-comparing solution techniques for more expressive problem formulations.

Similarity in Bilateral Isolated Internal Orbital Fractures.

Science.gov (United States)

Chen, Hung-Chang; Cox, Jacob T; Sanyal, Abanti; Mahoney, Nicholas R

2018-04-13

In evaluating patients sustaining bilateral isolated internal orbital fractures, the authors have observed both similar fracture locations and also similar expansion of orbital volumes. In this study, we aim to investigate if there is a propensity for the 2 orbits to fracture in symmetrically similar patterns when sustaining similar trauma. A retrospective chart review was performed studying all cases at our institution of bilateral isolated internal orbital fractures involving the medial wall and/or the floor at the time of presentation. The similarity of the bilateral fracture locations was evaluated using the Fisher's exact test. The bilateral expanded orbital volumes were analyzed using the Wilcoxon signed-rank test to assess for orbital volume similarity. Twenty-four patients with bilateral internal orbital fractures were analyzed for fracture location similarity. Seventeen patients (70.8%) had 100% concordance in the orbital subregion fractured, and the association between the right and the left orbital fracture subregion locations was statistically significant (P < 0.0001). Fifteen patients were analyzed for orbital volume similarity. The average orbital cavity volume was 31.2 ± 3.8 cm on the right and 32.0 ± 3.7 cm on the left. There was a statistically significant difference between right and left orbital cavity volumes (P = 0.0026). The data from this study suggest that an individual who suffers isolated bilateral internal orbital fractures has a statistically significant similarity in the location of their orbital fractures. However, there does not appear to be statistically significant similarity in the expansion of the orbital volumes in these patients.

On the Complexity of Inner Product Similarity Join

DEFF Research Database (Denmark)

Ahle, Thomas Dybdahl; Pagh, Rasmus; Razenshteyn, Ilya

2016-01-01

A number of tasks in classification, information retrieval, recommendation systems, and record linkage reduce to the core problem of inner product similarity join (IPS join): identifying pairs of vectors in a collection that have a sufficiently large inner product. IPS join is well understood when...... bounds for (A)LSH-based algorithms. In particular, we show that asymmetry can be avoided by relaxing the LSH definition to only consider the collision probability of distinct elements. A new indexing method for IPS based on linear sketches, implying that our hardness results are not far from being tight...

A metaheuristic for a numerical approximation to the mass transfer problem

Directory of Open Access Journals (Sweden)

Avendaño-Garrido Martha L.

2016-12-01

Full Text Available This work presents an improvement of the approximation scheme for the Monge-Kantorovich (MK mass transfer problem on compact spaces, which is studied by Gabriel et al. (2010, whose scheme discretizes the MK problem, reduced to solve a sequence of finite transport problems. The improvement presented in this work uses a metaheuristic algorithm inspired by scatter search in order to reduce the dimensionality of each transport problem. The new scheme solves a sequence of linear programming problems similar to the transport ones but with a lower dimension. The proposed metaheuristic is supported by a convergence theorem. Finally, examples with an exact solution are used to illustrate the performance of our proposal.

Towards Personalized Medicine: Leveraging Patient Similarity and Drug Similarity Analytics

Science.gov (United States)

Zhang, Ping; Wang, Fei; Hu, Jianying; Sorrentino, Robert

2014-01-01

The rapid adoption of electronic health records (EHR) provides a comprehensive source for exploratory and predictive analytic to support clinical decision-making. In this paper, we investigate how to utilize EHR to tailor treatments to individual patients based on their likelihood to respond to a therapy. We construct a heterogeneous graph which includes two domains (patients and drugs) and encodes three relationships (patient similarity, drug similarity, and patient-drug prior associations). We describe a novel approach for performing a label propagation procedure to spread the label information representing the effectiveness of different drugs for different patients over this heterogeneous graph. The proposed method has been applied on a real-world EHR dataset to help identify personalized treatments for hypercholesterolemia. The experimental results demonstrate the effectiveness of the approach and suggest that the combination of appropriate patient similarity and drug similarity analytics could lead to actionable insights for personalized medicine. Particularly, by leveraging drug similarity in combination with patient similarity, our method could perform well even on new or rarely used drugs for which there are few records of known past performance. PMID:25717413

Problem solving ability and repetition of deliberate self-harm: a multicentre study.

NARCIS (Netherlands)

McAuliffe, C.; Corcoran, P.; Keeley, H.S.; Arensman, E.; Bille Brahe, U.; de Leio, D.; Fekete, S.; Hawton, K.; Hjelmeland, H.; Kelleher, M.; Kerkhof, A.J.F.M.; Lonnqvist, J.; Michel, K.; Salander Renberg, E.; Schmidtke, A.; van Heeringen, K.; Wasserman, D.

2006-01-01

Background. While recent studies have found problem-solving impairments in individuals who engage in deliberate self-harm (DSH), few studies have examined repeaters and non-repeaters separately. The aim of the present study was to investigate whether specific types of problem-solving are associated

A Multi-Objective Approach to Visualize Proportions and Similarities Between Individuals by Rectangular Maps

DEFF Research Database (Denmark)

Carrizosa, Emilio; Guerrero, Vanesa; Morales, Dolores Romero

In this paper we address the problem of visualizing the proportions and the similarities attached to a set of individuals. We represent this information using a rectangular map, i.e., a subdivision of a rectangle into rectangular portions so that each portion is associated with one individual...... area and adjacency requirements, this visualization problem is formulated as a three-objective Mixed Integer Nonlinear Problem. The first objective seeks to maximize the number of true adjacencies that the rectangular map is able to reproduce, the second one is to minimize the number of false...

THE PROBLEM OF INTERDISCIPLINARITY IN LEARNING PROCESS STUDIES

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I. M. Osmolovskaya

2017-01-01

Full Text Available Introduction. The process of convergence and integration of scientific disciplines involves research in the field of education. Polydisciplinary studies wherein the knowledge is integrated from various scientific disciplines, do not meet the requirements of the solution of complex didactic problems, such as organization of the educational process in the information and educational environment, the construction of education for sustainable development of society, education in modern geopolitical conditions, etc. Thus, the importance of interdisciplinary research with a single subject matter, complementarity of research methods, integrated theoretical grounds and results, will make the contribution to all those scientific fields that are involved in assigned task solution.The aim of the article is to present intermediate results on identification and characteristic features of interdisciplinary studies in the field of education.Methodology and research methods. General scientific theoretical methods of research were used: analysis, comparison, fact-finding, generalization.Results and scientific novelty. An attempt to differentiate the concepts of interdisciplinarity, polydisciplinarity and transdisciplinarity is made. In spite of the fact that these issues are actively discussed in the field of philosophy, there are no precise and unambiguous definitions of these terms; though, there is a research framework, the author of the article makes reference to. The features of an interdisciplinary study are formulated.The functions of didactics as a scientific field are specified. Updating of interdisciplinary studies in education, need of formation of their specific methodologies and expansion of the research field of didactics by means of other interdisciplinary studies and scientific directions are proved. Psycho-didactic and cognitivedidactic studies are considered. Cognitive didactics at the moment does not seem to claim the status of independent

Travel-related health problems in Japanese travelers.

Science.gov (United States)

Mizuno, Yasutaka; Kudo, Koichiro

2009-09-01

Although the number of Japanese individuals traveling abroad has increased steadily, reaching approximately 17.3 million in 2007, the incidence of various travel-related health problems in Japan remains unknown. The travel-related health problems of Japanese travelers returning to Japan from abroad are analyzed by assessing the records. Data were collected retrospectively on returning travelers who visited the authors' travel clinic during the period from January 2005 through to December 2006 with any health problem acquired overseas. A total of 345 patients were included in this study (200 male, 145 female; average age, 34+/-12.3 years). Reasons for travel included leisure (45.8%); business (39.1%); visiting friends and relatives or accompanying other travelers (8.7%); volunteering (3.8%); and long stays in order to study or live (2.6%). The most visited destination was Asia (n=260), followed by Africa (n=105). The most commonly reported health problems were gastro-intestinal infections (39.1%), followed by respiratory tract infections (16.2%), animal bites (8.1%), and skin problems (5.8%). Together, malaria and dengue accounted for 10% of diagnoses in 125 febrile patients (36.2%). Although the profile of travel-related health problems in Japanese travelers is similar to that of Western travelers, the characteristics of travel were quite different. Therefore Japanese travel advice should be tailored to suit the Japanese traveler.

Self-Similar Traffic In Wireless Networks

OpenAIRE

Jerjomins, R.; Petersons, E.

2005-01-01

Many studies have shown that traffic in Ethernet and other wired networks is self-similar. This paper reveals that wireless network traffic is also self-similar and long-range dependant by analyzing big amount of data captured from the wireless router.

A study of the predictive model on the user reaction time using the information amount and its similarity

International Nuclear Information System (INIS)

Lee, Sung Jin; Heo, Gyun Young; Chang, Soon Heung

2004-01-01

There are lots of studies on the user interface evaluation since it started. Recent studies focus on the contextual information of the user interface. We knew that the user reaction time increases as the amount of information increases. But, the relation between the contextual information and the user reaction time may be unknown. In this study, we proposed the similarity as one of the contextual information. We can expect that the similarity decreases the user reaction time. The goal of this study is to find some correlation about the user reaction time with both the information amount and the similarity. The experiment was performed with 20 participants. The results of experiment demonstrated our proposals

Testing Self-Similarity Through Lamperti Transformations

KAUST Repository

Lee, Myoungji

2016-07-14

Self-similar processes have been widely used in modeling real-world phenomena occurring in environmetrics, network traffic, image processing, and stock pricing, to name but a few. The estimation of the degree of self-similarity has been studied extensively, while statistical tests for self-similarity are scarce and limited to processes indexed in one dimension. This paper proposes a statistical hypothesis test procedure for self-similarity of a stochastic process indexed in one dimension and multi-self-similarity for a random field indexed in higher dimensions. If self-similarity is not rejected, our test provides a set of estimated self-similarity indexes. The key is to test stationarity of the inverse Lamperti transformations of the process. The inverse Lamperti transformation of a self-similar process is a strongly stationary process, revealing a theoretical connection between the two processes. To demonstrate the capability of our test, we test self-similarity of fractional Brownian motions and sheets, their time deformations and mixtures with Gaussian white noise, and the generalized Cauchy family. We also apply the self-similarity test to real data: annual minimum water levels of the Nile River, network traffic records, and surface heights of food wrappings. © 2016, International Biometric Society.

Mental health problems among young doctors: an updated review of prospective studies.

Science.gov (United States)

Tyssen, Reidar; Vaglum, Per

2002-01-01

Previous studies have shown the medical community to exhibit a relatively high level of certain mental health problems, particularly depression, which may lead to drug abuse and suicide. We reviewed prospective studies published over the past 20 years to investigate the prevalence and predictors of mental health problems in doctors during their first postgraduate years. We selected clinically relevant mental health problems as the outcome measure. We found nine cohort studies that met our selection criteria. Each of them had limitations, notably low response rate at follow-up, small sample size, and/or short observation period. Most studies showed that symptoms of mental health problems, particularly of depression, were highest during the first postgraduate year. They found that individual factors, such as family background, personality traits (neuroticism and self-criticism), and coping by wishful thinking, as well as contextual factors including perceived medical-school stress, perceived overwork, emotional pressure, working in an intensive-care setting, and stress outside of work, were often predictive of mental health problems. The studies revealed somewhat discrepant findings with respect to gender. The implications of these findings are discussed.

Neural Substrates of Similarity and Rule-based Strategies in Judgment

Directory of Open Access Journals (Sweden)

Bettina eVon Helversen

2014-10-01

Full Text Available Making accurate judgments is a core human competence and a prerequisite for success in many areas of life. Plenty of evidence exists that people can employ different judgment strategies to solve identical judgment problems. In categorization, it has been demonstrated that similarity-based and rule-based strategies are associated with activity in different brain regions. Building on this research, the present work tests whether solving two identical judgment problems recruits different neural substrates depending on people's judgment strategies. Combining cognitive modeling of judgment strategies at the behavioral level with functional magnetic resonance imaging (fMRI, we compare brain activity when using two archetypal judgment strategies: a similarity-based exemplar strategy and a rule-based heuristic strategy. Using an exemplar-based strategy should recruit areas involved in long-term memory processes to a larger extent than a heuristic strategy. In contrast, using a heuristic strategy should recruit areas involved in the application of rules to a larger extent than an exemplar-based strategy. Largely consistent with our hypotheses, we found that using an exemplar-based strategy led to relatively higher BOLD activity in the anterior prefrontal and inferior parietal cortex, presumably related to retrieval and selective attention processes. In contrast, using a heuristic strategy led to relatively higher activity in areas in the dorsolateral prefrontal and the temporal-parietal cortex associated with cognitive control and information integration. Thus, even when people solve identical judgment problems, different neural substrates can be recruited depending on the judgment strategy involved.

Evaluating Students' Beliefs in Problem Solving Process: A Case Study

Science.gov (United States)

Ozturk, Tugba; Guven, Bulent

2016-01-01

Problem solving is not simply a process that ends when an answer is found; it is a scientific process that evolves from understanding the problem to evaluating the solution. This process is affected by several factors. Among these, one of the most substantial is belief. The purpose of this study was to evaluate the beliefs of high school students…

A Genetic Study of Problem Behaviors in Children

NARCIS (Netherlands)

E.J.C.G. van den Oord (Edwin)

1993-01-01

textabstractBehavioral/emotional problems are common among children of preschool and school age. Verhulst, and Koot (1992, p. 130) reviewed prevalence studies published since 1965. They reported a median prevalence rate for general psychiatric dysfunction in children and adolescents of l3%. This

Possibilities and problems connected with the use of inverters

Energy Technology Data Exchange (ETDEWEB)

Brandolini, A

1968-01-01

The problem, which is not new, of dc electrical nets, feeding ac users, was investigated. An analytical treatment was carried out for studying a system formed by a dc line feeding a load through an inverter, with the result of keeping, for the expressions of the active and apparent power, forms which are similar to those of the simple sinusoidal case. It resulted that in the operation of dc ac mixed nets the problems involving the exchange of nonactive power are not more difficult than those which occur in common ac nets.

Analogical Problem Solving in Children with Verbal and Nonverbal Learning Disabilities

Science.gov (United States)

Schiff, Rachel; Bauminger, Nirit; Toledo, Idit

2009-01-01

Analogical reasoning--perceiving similarities in different situations and the transfer of such information--facilitates learning and understanding. However, children with learning disabilities (LD) typically demonstrate deficits in such information processing strategies. In this study, we investigated the analogical problem-solving differences…

Data mining technique for fast retrieval of similar waveforms in Fusion massive databases

International Nuclear Information System (INIS)

Vega, J.; Pereira, A.; Portas, A.; Dormido-Canto, S.; Farias, G.; Dormido, R.; Sanchez, J.; Duro, N.; Santos, M.; Sanchez, E.; Pajares, G.

2008-01-01

Fusion measurement systems generate similar waveforms for reproducible behavior. A major difficulty related to data analysis is the identification, in a rapid and automated way, of a set of discharges with comparable behaviour, i.e. discharges with 'similar' waveforms. Here we introduce a new technique for rapid searching and retrieval of 'similar' signals. The approach consists of building a classification system that avoids traversing the whole database looking for similarities. The classification system diminishes the problem dimensionality (by means of waveform feature extraction) and reduces the searching space to just the most probable 'similar' waveforms (clustering techniques). In the searching procedure, the input waveform is classified in any of the existing clusters. Then, a similarity measure is computed between the input signal and all cluster elements in order to identify the most similar waveforms. The inner product of normalized vectors is used as the similarity measure as it allows the searching process to be independent of signal gain and polarity. This development has been applied recently to TJ-II stellarator databases and has been integrated into its remote participation system

Television viewing and externalizing problems in preschool children: the Generation R Study.

Science.gov (United States)

Verlinden, Marina; Tiemeier, Henning; Hudziak, James J; Jaddoe, Vincent W V; Raat, Hein; Guxens, Mònica; Hofman, Albert; Verhulst, Frank C; Jansen, Pauline W

2012-10-01

To determine whether the amount, type, and patterns of television viewing predict the onset or the persistence of externalizing problems in preschool children. Longitudinal study of a prospective population-based cohort in the Netherlands. Parents reported time of television exposure and type of programs watched by children. Externalizing problems were assessed using the Child Behavior Checklist at 18 and 36 months. A population-based sample of 3913 children. Television viewing time, content, and patterns of exposure (at 24 and 36 months) in children with and without preexisting problems to assess the incidence and persistence of externalizing problems. Externalizing problems at 36 months. Program content and time of television exposure assessed at 24 months did not predict the incidence of externalizing problems at 36 months (odds ratio, 2.24; 95% CI, 0.97-5.18). However, the patterns of exposure over time reflecting high levels of television viewing were associated with the incidence of externalizing problems (odds ratio, 2.00; 95% CI, 1.07-3.75) and the persistence of the preexisting externalizing problems (2.59; 1.03-6.55). Our study showed that high television exposure increases the risk of the incidence and the persistence of externalizing problems in preschool children.

[Evaluation of Educational Effect of Problem-Posing System in Nursing Processing Study].

Science.gov (United States)

Tsuji, Keiko; Takano, Yasuomi; Yamakawa, Hiroto; Kaneko, Daisuke; Takai, Kiyako; Kodama, Hiromi; Hagiwara, Tomoko; Komatsugawa, Hiroshi

2015-09-01

The nursing processing study is generally difficult, because it is important for nursing college students to understand knowledge and utilize it. We have developed an integrated system to understand, utilize, and share knowledge. We added a problem-posing function to this system, and expected that students would deeply understand the nursing processing study through the new system. This system consisted of four steps: create a problem, create an answer input section, create a hint, and verification. Nursing students created problems related to nursing processing by this system. When we gave a lecture on the nursing processing for second year students of A university, we tried to use the creating problem function of this system. We evaluated the effect by the number of problems and the contents of the created problem, that is, whether the contents consisted of a lecture stage or not. We also evaluated the correlation between those and regular examination and report scores. We derived the following: 1. weak correlation between the number of created problems and report score (r=0.27), 2. significant differences between regular examination and report scores of students who created problems corresponding to the learning stage, and those of students who created problems not corresponding to it (P<0.05). From these results, problem-posing is suggested to be effective to fix and utilize knowledge in the lecture of nursing processing theory.

Treatment of forefoot problems in older people: study protocol for a randomised clinical trial comparing podiatric treatment to standardised shoe advice

Directory of Open Access Journals (Sweden)

Peeraer Louis

2011-03-01

Full Text Available Abstract Background Foot problems in general and forefoot problems in particular can lead to a decrease in mobility and a higher risk of falling. Forefoot problems increase with age and are more common in women than in men. Around 20% of people over 65 suffer from non-traumatic foot problems and 60% of these problems are localised in the forefoot. Little is known about the best way to treat forefoot problems in older people. The aim of this study is to compare the effects of two common modes of treatment in the Netherlands: shoe advice and podiatric treatment. This paper describes the design of this study. Methods The study is designed as a pragmatic randomised clinical trial (RCT with 2 parallel intervention groups. People aged 50 years and over who have visited their general practitioner (GP with non traumatic pain in the forefoot in the preceding year and those who will visit their GP during the recruitment period with a similar complaint will be recruited for this study. Participants must be able to walk unaided for 7 metres and be able to fill in questionnaires. Exclusion criteria are: rheumatoid arthritis, neuropathy of the foot or pain caused by skin problems (e.g. warts, eczema. Inclusion and exclusion criteria will be assessed by a screening questionnaire and baseline assessment. Those consenting to participation will be randomly assigned to either a group receiving a standardised shoe advice leaflet (n = 100 or a group receiving podiatric treatment (n = 100. Primary outcomes will be the severity of forefoot pain (0-10 on a numerical rating scale and foot function (Foot Function 5-pts Index and Manchester Foot Pain and Disability Index. Treatment adherence, social participation and quality of life will be the secondary outcomes. All outcomes will be obtained through self-administered questionnaires at the start of the study and after 3, 6, 9 and 12 months. Data will be analysed according to the "intention-to-treat" principle using

Sleep Problems Before and After Acute Myocardial Infarction: A Comparative Study

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Belguzar Kara

2012-12-01

Full Text Available AIM: The purpose of this study was to compare patients’ sleep problems before and after acute myocardial infarction (AMI and also to determine factors affecting sleep problems in patients undergoing AMI. METHOD: This cross-sectional study was conducted at the Coronary Intensive Care Unit in a training hospital between January 1 and April 30, 2007. The sample of the study was composed of 26 patients with a first-ever AMI. Data were collected by using a questionnaire to determine the patient and illness-related descriptive characteristics and the Post Sleep Inventory Scale (PSIS. The Shapiro-Wilks test, descriptive statistics, paired samples t test, Mann Whitney U test, Wilcoxon test, reliability analysis and correlation analysis were used to analyze the data. RESULTS: The mean age of the study group was 53.2 ± 12.6 years and approximately 81% were males. The patients’ mean bedtime (t= -3.422, p= 0.001, quality of nocturnal sleep (t= -3.221, p= 0.001, awakening (t =-3.533, p<0.001 and total PSIS scores (t= -5.652, p<0.001 were significantly higher after AMI compared to before AMI. The mean PSIS scores of patients undergoing AMI were statistically significant different by gender (z= -2.164, p= 0.030 and working status (z= -2.171, p= 0.030. There was a negative correlation between the PSIS score and haemoglobin and haematocrit values (r= -0.503, p<0.01; r= -0.473, p<0.05; respectively. CONCLUSION: There were differences in the patients’ reported sleep problems between before and after AMI. The results of this study showed that sleep problems were more common among women, patients not working and those with anemia. Nurses should be aware of the sleep problems and factors that affect to sleep problems. [TAF Prev Med Bull 2012; 11(6.000: 687-694

Personality similarity and life satisfaction in couples

OpenAIRE

Furler Katrin; Gomez Veronica; Grob Alexander

2013-01-01

The present study examined the association between personality similarity and life satisfaction in a large nationally representative sample of 1608 romantic couples. Similarity effects were computed for the Big Five personality traits as well as for personality profiles with global and differentiated indices of similarity. Results showed substantial actor and partner effects indicating that both partners' personality traits were related to both partners' life satisfaction. Personality similar...

Optimizing investment fund allocation using vehicle routing problem framework

Science.gov (United States)

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

2014-07-01

The objective of investment is to maximize total returns or minimize total risks. To determine the optimum order of investment, vehicle routing problem method is used. The method which is widely used in the field of resource distribution shares almost similar characteristics with the problem of investment fund allocation. In this paper we describe and elucidate the concept of using vehicle routing problem framework in optimizing the allocation of investment fund. To better illustrate these similarities, sectorial data from FTSE Bursa Malaysia is used. Results show that different values of utility for risk-averse investors generate the same investment routes.

Soldier motivation – different or similar?

DEFF Research Database (Denmark)

Brænder, Morten; Andersen, Lotte Bøgh

Recent research in military sociology has shown that in addition to their strong peer motivation modern soldiers are oriented toward contributing to society. It has not, however, been tested how soldier motivation differs from the motivation of other citizens in this respect. In this paper......, by means of public service motivation, a concept developed within the public administration literature, we compare soldier and civilian motivation. The contribution of this paper is an analysis of whether and how Danish combat soldiers differs from other Danes in regard to public service motivation? Using...... surveys with similar questions, we find that soldiers are more normatively motivated to contribute to society than other citizens (higher commitment to the public interest), while their affectively based motivation is lower (lower compassion). This points towards a potential problem in regard...

Feeding problems in infancy and early childhood: A case study of ...

African Journals Online (AJOL)

Feeding problems in infancy and early childhood: A case study of selected ... of feeding problems among children 6 to 24 months of age in Ibadan, Nigeria. ... from four selected Primary Health Centres in Ibadan North Local Government Area.

MANAGERIAL PROBLEMS CONFRONTED BY EXECUTIVE CHEFS IN HOTELS

Directory of Open Access Journals (Sweden)

Kemal BIRDIR

2014-07-01

Full Text Available The study was conducted to determine the managerial problems confronted by executive chefs working at 4 and 5-star hotels in Turkey. A survey developed by the researchers was employed as a data collection tool. Answers given by participants were analyzed using “T-test” and “ANOVA” analyses in order to determine whether there are significant differences of opinion on the subject (collated in answers to the survey questionnaire amongst executive chefs, based on answers given by them (expressed as average figures dependent upon such variables as their “Age”, “Gender”, “Educational Status” and “Star status of the hotel within which they worked.” The study results showed that the most important problem confronting executive chefs was “finding educated/trained kitchen personnel.” On the specific problem, “responsibility and authority is not clear within the kitchen,” there was a significant difference of opinion by the gender of the executive chefs. Moreover, there was a significant difference of opinion dependent upon the star status of the hotels within which the chefs worked on the problem of whether or not “the working hours of kitchen personnel were too long.” The findings suggest that there are important problems confronted by executive chefs. Moreover, male and female executive chefs have different opinions on the magnitudes of some specific problems. Whereas there are various reports and similar publications discussing problems faced by executive chefs, the present study is the first one in the literature that solely explore the managerial problems experienced at a kitchen context.

The Relationship Between Psychological Distress, Negative Cognitions, and Expectancies on Problem Drinking: Exploring a Growing Problem Among University Students.

Science.gov (United States)

Obasi, Ezemenari M; Brooks, Jessica J; Cavanagh, Lucia

2016-01-01

Few studies have sought to understand the concurrent relationship between cognitive and affective processes on alcohol use and negative alcohol-related consequences, despite both being identified as predictive risk factors in the college population. More research is needed to understand the relationships between identified factors of problem drinking among this at-risk population. The purpose of this study was to test if the relationship between psychological distress and problem drinking among university students (N = 284; M-age = 19.77) was mediated by negative affect regulation strategies and positive alcohol-related expectancies. Two latent mediation models of problem drinking were tested using structural equation modeling (SEM). The parsimonious three-path mediated latent model was supported by the data, as evidenced by several model fit indices. Furthermore, the alternate saturated model provided similar fit to the data, but contained several direct relationships that were not statistically significant. The relationship between psychological distress and problem drinking was mediated by an extended contributory chain, including negative affect regulation and positive alcohol-related expectancies. Implications for prevention and treatment, as well as future directions, are discussed. © The Author(s) 2015.

Neurobiological correlates of internet gaming disorder: Similarities to pathological gambling.

Science.gov (United States)

Fauth-Bühler, M; Mann, K

2017-01-01

The number of massively multiplayer online games (MMOs) is on the rise worldwide along with the fascination that they inspire. Problems occur when the use of MMOs becomes excessive at the expense of other life domains. Although not yet formally included as disorder in common diagnostic systems, internet gaming disorder (IGD) is considered a "condition for further study" in section III of the DSM-5. The current review aims to provide an overview of cognitive and neurobiological data currently available on IGD, with a particular focus on impulsivity, compulsivity, and sensitivity to reward and punishment. Additionally, we also compare these findings on IGD with data from studies on pathological gambling (PG)-so far the only condition officially classified as a behavioral addiction in the DSM-5. Multiple similarities have been observed in the neurobiology of IGD and PG, as measured by alterations in brain function and behavior. Both patients with IGD and those with PG exhibited decreased loss sensitivity; enhanced reactivity to gaming and gambling cues, respectively; enhanced impulsive choice behavior; aberrant reward-based learning; and no changes in cognitive flexibility. In conclusion, the evidence base on the neurobiology of gaming and gambling disorders is beginning to illuminate the similarities between the two. However, as only a few studies have addressed the neurobiological basis of IGD, and some of these studies suffer from significant limitations, more research is required before IGD's inclusion as a second behavioral addiction in the next versions of the ICD and DSM can be justified. Copyright © 2015 Elsevier Ltd. All rights reserved.

Men with Sexual Problems and Their Partners: Findings from the International Survey of Relationships.

Science.gov (United States)

Rosen, Raymond C; Heiman, Julia R; Long, J Scott; Fisher, William A; Sand, Michael S

2016-01-01

Epidemiologic studies of sexual function problems in men have focused on the individual male and related sociodemographic characteristics, individual risk factors and lifestyle concomitants, or medical comorbidities. Insufficient attention has been given to the role of sexual and relationship satisfaction and, more particularly, to the perspective of the couple as causes or correlates of sexual problems in men or women. Previously, we reported results of the first large, multi-national study of sexual satisfaction and relationship happiness in 1,009 midlife and older couples in five countries (Brazil, Germany, Japan, Spain, U.S.). For the present study, we examined, within each problem, the association of four major sexual problems in men (loss of sexual desire, erectile problems, premature ejaculation, delayed/absent orgasm) and multiple problems, with male and female partners' assessments of physical intimacy, sexual satisfaction, and relationship happiness, as well as associations with well-known health and psychosocial correlates of sexual problems in men. Sexual problem rates of men in our survey were generally similar to rates observed in past surveys in the general population, and similar risk factors (age, relationship duration, overall health) were associated with lack of desire, anorgasmia, or erection difficulties in our sample. As in previous surveys, there were few correlates of premature ejaculation. As predicted, men with one or more sexual problems reported decreased relationship happiness as well as decreased sexual satisfaction compared to men without sexual problems. Moreover, female partners of men with sexual problems had reduced relationship happiness and sexual satisfaction, although these latter outcomes were less affected in the women than the men. The association of men's sexual problems with men's and women's satisfaction and relationship happiness were modest, as these couples in long-term, committed relationships were notable for their

Anomalous Traffic Detection and Self-Similarity Analysis in the Environment of ATMSim

Directory of Open Access Journals (Sweden)

Hae-Duck J. Jeong

2017-12-01

Full Text Available Internet utilisation has steadily increased, predominantly due to the rapid recent development of information and communication networks and the widespread distribution of smartphones. As a result of this increase in Internet consumption, various types of services, including web services, social networking services (SNS, Internet banking, and remote processing systems have been created. These services have significantly enhanced global quality of life. However, as a negative side-effect of this rapid development, serious information security problems have also surfaced, which has led to serious to Internet privacy invasions and network attacks. In an attempt to contribute to the process of addressing these problems, this paper proposes a process to detect anomalous traffic using self-similarity analysis in the Anomaly Teletraffic detection Measurement analysis Simulator (ATMSim environment as a research method. Simulations were performed to measure normal and anomalous traffic. First, normal traffic for each attack, including the Address Resolution Protocol (ARP and distributed denial-of-service (DDoS was measured for 48 h over 10 iterations. Hadoop was used to facilitate processing of the large amount of collected data, after which MapReduce was utilised after storing the data in the Hadoop Distributed File System (HDFS. A new platform on Hadoop, the detection system ATMSim, was used to identify anomalous traffic after which a comparative analysis of the normal and anomalous traffic was performed through a self-similarity analysis. There were four categories of collected traffic that were divided according to the attack methods used: normal local area network (LAN traffic, DDoS attack, and ARP spoofing, as well as DDoS and ARP attack. ATMSim, the anomaly traffic detection system, was used to determine if real attacks could be identified effectively. To achieve this, the ATMSim was used in simulations for each scenario to test its ability to

Choosing preclinical study models of diabetic retinopathy: key problems for consideration

Science.gov (United States)

Mi, Xue-Song; Yuan, Ti-Fei; Ding, Yong; Zhong, Jing-Xiang; So, Kwok-Fai

2014-01-01

Diabetic retinopathy (DR) is the most common complication of diabetes mellitus in the eye. Although the clinical treatment for DR has already developed to a relative high level, there are still many urgent problems that need to be investigated in clinical and basic science. Currently, many in vivo animal models and in vitro culture systems have been applied to solve these problems. Many approaches have also been used to establish different DR models. However, till now, there has not been a single study model that can clearly and exactly mimic the developmental process of the human DR. Choosing the suitable model is important, not only for achieving our research goals smoothly, but also, to better match with different experimental proposals in the study. In this review, key problems for consideration in choosing study models of DR are discussed. These problems relate to clinical relevance, different approaches for establishing models, and choice of different species of animals as well as of the specific in vitro culture systems. Attending to these considerations will deepen the understanding on current study models and optimize the experimental design for the final goal of preventing DR. PMID:25429204

Investigating Pre-service Mathematics Teachers’ Geometric Problem Solving Process in Dynamic Geometry Environment

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Deniz Özen

2013-03-01

Full Text Available The aim of this study is to investigate pre-service elementary mathematics teachers’ open geometric problem solving process in a Dynamic Geometry Environment. With its qualitative inquiry based research design employed, the participants of the study are three pre-service teachers from 4th graders of the Department of Elementary Mathematics Teaching. In this study, clinical interviews, screencaptures of the problem solving process in the Cabri Geomery Environment, and worksheets included 2 open geometry problems have been used to collect the data. It has been investigated that all the participants passed through similar recursive phases as construction, exploration, conjecture, validate, and justification in the problem solving process. It has been thought that this study provide a new point of view to curriculum developers, teachers and researchers

Problems of Clinical Nurse Performance Appraisal System: A Qualitative Study

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Nasrin Nikpeyma

2014-03-01

Conclusion: The findings of this study reveal that the nurse performance appraisal system confronts with various problems. Some of these problems are related to organizational context while the others concerned structure, process and results of the performance appraisal system. In order to achieve high quality of patient care as the final goal of performance appraisal, changing and revision of this system is necessary.

Identification of spectrally similar materials using the USGS Tetracorder algorithm: The calcite-epidote-chlorite problem

Science.gov (United States)

Dalton, J.B.; Bove, D.J.; Mladinich, C.S.; Rockwell, B.W.

2004-01-01

A scheme to discriminate and identify materials having overlapping spectral absorption features has been developed and tested based on the U.S. Geological Survey (USGS) Tetracorder system. The scheme has been applied to remotely sensed imaging spectroscopy data acquired by the Airborne Visible and Infrared Imaging Spectrometer (AVIRIS) instrument. This approach was used to identify the minerals calcite, epidote, and chlorite in the upper Animas River watershed, Colorado. The study was motivated by the need to characterize the distribution of calcite in the watershed and assess its acid-neutralizing potential with regard to acidic mine drainage. Identification of these three minerals is difficult because their diagnostic spectral features are all centered at 2.3 ??m, and have similar shapes and widths. Previous studies overestimated calcite abundance as a result of these spectral overlaps. The use of a reference library containing synthetic mixtures of the three minerals in varying proportions was found to simplify the task of identifying these minerals when used in conjunction with a rule-based expert system. Some inaccuracies in the mineral distribution maps remain, however, due to the influence of a fourth spectral component, sericite, which exhibits spectral absorption features at 2.2 and 2.4 ??m that overlap the 2.3-??m absorption features of the other three minerals. Whereas the endmember minerals calcite, epidote, chlorite, and sericite can be identified by the method presented here, discrepancies occur in areas where all four occur together as intimate mixtures. It is expected that future work will be able to reduce these discrepancies by including reference mixtures containing sericite. ?? 2004 Elsevier Inc. All rights reserved.

Does a parental history of cancer moderate the associations between impaired health status in parents and psychosocial problems in teenagers: a HUNT study.

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Jeppesen, Elisabeth; Bjelland, Ingvar; Fosså, Sophie D; Loge, Jon H; Sørebø, Oystein; Dahl, Alv A

2014-08-01

Severe disease in a parent is associated with increased psychosocial problems in their children. However, moderating factors of such associations are less studied. In this cross-sectional population-based controlled study we examined the moderating effects of a history of parental cancer on the association between impaired health status in parents and psychosocial problems among their teenagers. Among families with both parents responding to the adult Health Survey of Nord-Trøndelag County of Norway (the HUNT-2 study) 71 couples were identified with primary invasive cancer in one parent. Their 81 teenage children took part in the Young-HUNT study. These families were compared to 322 cancer-free families with 328 teenagers. Based on self-report data the relations between three variables of parental impaired health and six psychosocial problems in teenagers were analyzed family wise by structural equation modeling. Significant associations between parental and teenagers' variables were observed in eight of 18 models. A history of parental cancer was a significant moderator which decreased four of eight significant associations. Such a history significantly weakened the associations between parental poor self-rated health and teenagers' anxiety/depression and school problems. A similar association of a history of parental cancer was found between psychological distress in parents and teenagers' feelings of loneliness and poor self-rated health. This study confirmed strong associations between impaired parental health and psychosocial problems in their teenagers. A history of parental cancer weakened several of the significant associations between parental impaired health variables and psychosocial problems in their teenagers. © 2014 The Authors. Cancer Medicine published by John Wiley & Sons Ltd.

The prevalence, incidence, and gender and age-specific incidence of problem gambling: results of the Swedish longitudinal gambling study (Swelogs).

Science.gov (United States)

Abbott, Max; Romild, Ulla; Volberg, Rachel

2018-04-01

To estimate the prevalence, incidence and gender and age-specific incidence of problem gambling in the Swedish adult population. Longitudinal cohort study with linkage to register data. Sweden. Stratified random sample aged 16-84 years at baseline (n = 8165) re-assessed a year later (n = 6021). Problem gambling (life-time and past 12 months) was measured by the South Oaks Gambling Screen-Revised (SOGS-R). Past 12-month (current) problem gambling was also measured by the Problem Gambling Severity Index (PGSI). The SOGS-R combined current pathological and problem gambling prevalence rate (PR) was 2.1 [95% confidence interval (CI) = 1.8-2.4] at baseline and 1.7 (1.4-2.0) at follow-up, approximately half the corresponding life-time estimates.[Correction added on 22 Dec 2017, after first online publication: In the preceding sentence, the SOGS-R combined current pathological and problem gambling prevalence rate (PR) was incorrectly reported as being double the corresponding life-time rate. It has been corrected in this version.] PGSI combined current problem and moderate-risk gambling PRs were 2.2 (1.9-2.5) at baseline and 1.9 (1.6-2.2) at follow-up. Combined incidence rates (IRs) were 1.0 (0.8-1.3) (SOGS-R) and 1.4 (1.1-1.7) (PGSI), with more than three-quarters being new cases. While first-time IRs did not vary by gender, males had a higher relapse IR and proportionately more females were new cases. The young adult IR was more than double the older adult IR; similar proportions were new cases. The actual incidence of problem gambling relapse in Sweden is likely to be higher than estimated. The profile of problem gambling in Sweden is likely to change over time, with increased proportions of women and older adults. © 2017 Society for the Study of Addiction.

Learned helplessness in chess players: the importance of task similarity and the role of skill.

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Gobet, F R

1992-01-01

The effects of noncontingency between subjects' responses and outcomes were examined with respect to treatment-and-posttest similarity and skill in the task. The experimental design consisted of three groups. The first group had to solve chess problems with objective solutions and received veridical feedback; each member of the second group faced problems with no objective solutions, and received the same feedback as the member of the first group he was yoked with, but without any control on it; the control group received a waiting task. It was found at the end of the experiment that the group with unsolvable problems was more depressed than the two other groups. The mid-strength players were the most sensitive to the manipulation, and the weakest players showed little effect of learned helplessness. It was also found that the effects were proportional to the degree of similarity between the treatment and the posttest. The results limit the domain of applicability of the learned-helplessness model.

Computational Study on a PTAS for Planar Dominating Set Problem

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Qian-Ping Gu

2013-01-01

Full Text Available The dominating set problem is a core NP-hard problem in combinatorial optimization and graph theory, and has many important applications. Baker [JACM 41,1994] introduces a k-outer planar graph decomposition-based framework for designing polynomial time approximation scheme (PTAS for a class of NP-hard problems in planar graphs. It is mentioned that the framework can be applied to obtain an O(2ckn time, c is a constant, (1+1/k-approximation algorithm for the planar dominating set problem. We show that the approximation ratio achieved by the mentioned application of the framework is not bounded by any constant for the planar dominating set problem. We modify the application of the framework to give a PTAS for the planar dominating set problem. With k-outer planar graph decompositions, the modified PTAS has an approximation ratio (1 + 2/k. Using 2k-outer planar graph decompositions, the modified PTAS achieves the approximation ratio (1+1/k in O(22ckn time. We report a computational study on the modified PTAS. Our results show that the modified PTAS is practical.

Problems in the theory of point explosions

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Korobeinikov, V. P.

The book is concerned with the development of the theory of point explosions, which is relevant to the study of such phenomena as the initiation of detonation, high-power explosions, electric discharges, cosmic explosions, laser blasts, and hypersonic aerodynamics. The discussion covers the principal equations and the statement of problems; linearized non-self-similar one-dimensional problems; spherical, cylindrical, and plane explosions with allowance for counterpressure under conditions of constant initial density; explosions in a combustible mixture of gases; and point explosions in inhomogeneous media with nonsymmetric energy release. Attention is also given to point explosions in an electrically conducting gas with allowance for the effect of the magnetic field and to the propagation of perturbations from solar flares.

On bi-criteria two-stage transportation problem: a case study

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Ahmad MURAD

2010-01-01

Full Text Available The study of the optimum distribution of goods between sources and destinations is one of the important topics in projects economics. This importance comes as a result of minimizing the transportation cost, deterioration, time, etc. The classical transportation problem constitutes one of the major areas of application for linear programming. The aim of this problem is to obtain the optimum distribution of goods from different sources to different destinations which minimizes the total transportation cost. From the practical point of view, the transportation problems may differ from the classical form. It may contain one or more objective function, one or more stage to transport, one or more type of commodity with one or more means of transport. The aim of this paper is to construct an optimization model for transportation problem for one of mill-stones companies. The model is formulated as a bi-criteria two-stage transportation problem with a special structure depending on the capacities of suppliers, warehouses and requirements of the destinations. A solution algorithm is introduced to solve this class of bi-criteria two-stage transportation problem to obtain the set of non-dominated extreme points and the efficient solutions accompanied with each one that enables the decision maker to choose the best one. The solution algorithm mainly based on the fruitful application of the methods for treating transportation problems, theory of duality of linear programming and the methods of solving bi-criteria linear programming problems.

Similar or different? The role of the ventrolateral prefrontal cortex in similarity detection.

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Béatrice Garcin

Full Text Available Patients with frontal lobe syndrome can exhibit two types of abnormal behaviour when asked to place a banana and an orange in a single category: some patients categorize them at a concrete level (e.g., "both have peel", while others continue to look for differences between these objects (e.g., "one is yellow, the other is orange". These observations raise the question of whether abstraction and similarity detection are distinct processes involved in abstract categorization, and that depend on separate areas of the prefrontal cortex (PFC. We designed an original experimental paradigm for a functional magnetic resonance imaging (fMRI study involving healthy subjects, confirming the existence of two distinct processes relying on different prefrontal areas, and thus explaining the behavioural dissociation in frontal lesion patients. We showed that: 1 Similarity detection involves the anterior ventrolateral PFC bilaterally with a right-left asymmetry: the right anterior ventrolateral PFC is only engaged in detecting physical similarities; 2 Abstraction per se activates the left dorsolateral PFC.

One-Year Prospective Study on Passion and Gambling Problems in Poker Players.

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Morvannou, Adèle; Dufour, Magali; Brunelle, Natacha; Berbiche, Djamal; Roy, Élise

2018-06-01

The concept of passion is relevant to understanding gambling behaviours and gambling problems. Longitudinal studies are useful to better understand the absence and development of gambling problems; however, only one study has specifically considered poker players. Using a longitudinal design, this study aims to determine the influence, 1 year later, of two forms of passion-harmonious and obsessive-on gambling problems in poker players. A total of 116 poker players was recruited from across Quebec, Canada. The outcome variable of interest was participants' category on the Canadian Pathological Gambling Index, and the predictive variable was the Gambling Passion Scale. Multiple logistic regression analyses were conducted to identify independent risk factors of at-risk poker players 1 year later. Obsessive passion at baseline doubled the risk of gambling problems 1 year later (p passion, there was no association. Number of gambling activities, drug problems, and impulsivity were also associated with at-risk gambling. This study highlights the links between obsessive passion and at-risk behaviours among poker players. It is therefore important to prevent the development of obsessive passion among poker players.

Benchmark problem suite for reactor physics study of LWR next generation fuels

International Nuclear Information System (INIS)

Yamamoto, Akio; Ikehara, Tadashi; Ito, Takuya; Saji, Etsuro

2002-01-01

This paper proposes a benchmark problem suite for studying the physics of next-generation fuels of light water reactors. The target discharge burnup of the next-generation fuel was set to 70 GWd/t considering the increasing trend in discharge burnup of light water reactor fuels. The UO 2 and MOX fuels are included in the benchmark specifications. The benchmark problem consists of three different geometries: fuel pin cell, PWR fuel assembly and BWR fuel assembly. In the pin cell problem, detailed nuclear characteristics such as burnup dependence of nuclide-wise reactivity were included in the required calculation results to facilitate the study of reactor physics. In the assembly benchmark problems, important parameters for in-core fuel management such as local peaking factors and reactivity coefficients were included in the required results. The benchmark problems provide comprehensive test problems for next-generation light water reactor fuels with extended high burnup. Furthermore, since the pin cell, the PWR assembly and the BWR assembly problems are independent, analyses of the entire benchmark suite is not necessary: e.g., the set of pin cell and PWR fuel assembly problems will be suitable for those in charge of PWR in-core fuel management, and the set of pin cell and BWR fuel assembly problems for those in charge of BWR in-core fuel management. (author)

Experiences of Primiparous Mothers Regarding Natural Childbirth Problems (A Qualitative Study

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Tahereh Boryri

2016-07-01

Full Text Available Women experience several problems during the childbirth process which always remain with them throughout their lives. These problems affect the health of the mother and the child, the emotional relationship between them, the sexual activity and the desire to have her next child in the future. This qualitative study is designed to explore the experiences of primiparous women about natural childbirth problems. This qualitative study is conducted on primiparous women who referred to the health center of Imam Javad in Zahedan. The sample selection is based on objective; the data are collected using semi-structured interviews with 18 primiparous mothers who had healthy natural childbirth. The data are collected through an interview that is done in the first visit within 72 hours after the childbirth, and the data are analyzed through content analysis. After analysis of the data, four themes associated with the problem of the first natural childbirth are extracted. The first is the fear and stress of the labor pain that most participants expressed as the major problem of natural childbirth. The second theme is lack of awareness and lack of information about the process of labor and the delivery room environment; this means that participants of this study are mostly unfamiliar with the process of labor and the delivery room environment and this leads to their fear and pain. The other two themes are the need for protection and support of the mothers by the midwives, their family and their friends. Based on the results of this study, the problems of human resources are stated as being more serious than the problems regarding the environment and modern equipment. This leads to the increase of attention of the midwives and other medical staff on psychological and spiritual needs of mothers and supporting them during the labor in addition to the physical health of the mother and the fetus. In this regard, childbirth classes are recommended in outlining the

EVALUATION OF SEMANTIC SIMILARITY FOR SENTENCES IN NATURAL LANGUAGE BY MATHEMATICAL STATISTICS METHODS

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A. E. Pismak

2016-03-01

Full Text Available Subject of Research. The paper is focused on Wiktionary articles structural organization in the aspect of its usage as the base for semantic network. Wiktionary community references, article templates and articles markup features are analyzed. The problem of numerical estimation for semantic similarity of structural elements in Wiktionary articles is considered. Analysis of existing software for semantic similarity estimation of such elements is carried out; algorithms of their functioning are studied; their advantages and disadvantages are shown. Methods. Mathematical statistics methods were used to analyze Wiktionary articles markup features. The method of semantic similarity computing based on statistics data for compared structural elements was proposed.Main Results. We have concluded that there is no possibility for direct use of Wiktionary articles as the source for semantic network. We have proposed to find hidden similarity between article elements, and for that purpose we have developed the algorithm for calculation of confidence coefficients proving that each pair of sentences is semantically near. The research of quantitative and qualitative characteristics for the developed algorithm has shown its major performance advantage over the other existing solutions in the presence of insignificantly higher error rate. Practical Relevance. The resulting algorithm may be useful in developing tools for automatic Wiktionary articles parsing. The developed method could be used in computing of semantic similarity for short text fragments in natural language in case of algorithm performance requirements are higher than its accuracy specifications.

Using isomorphic problems to learn introductory physics

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Shih-Yin Lin

2011-08-01

Full Text Available In this study, we examine introductory physics students’ ability to perform analogical reasoning between two isomorphic problems which employ the same underlying physics principles but have different surface features. Three hundred sixty-two students from a calculus-based and an algebra-based introductory physics course were given a quiz in the recitation in which they had to first learn from a solved problem provided and take advantage of what they learned from it to solve another problem (which we call the quiz problem which was isomorphic. Previous research suggests that the multiple-concept quiz problem is challenging for introductory students. Students in different recitation classes received different interventions in order to help them discern and exploit the underlying similarities of the isomorphic solved and quiz problems. We also conducted think-aloud interviews with four introductory students in order to understand in depth the difficulties they had and explore strategies to provide better scaffolding. We found that most students were able to learn from the solved problem to some extent with the scaffolding provided and invoke the relevant principles in the quiz problem. However, they were not necessarily able to apply the principles correctly. Research suggests that more scaffolding is needed to help students in applying these principles appropriately. We outline a few possible strategies for future investigation.

Using isomorphic problems to learn introductory physics

Science.gov (United States)

Lin, Shih-Yin; Singh, Chandralekha

2011-12-01

In this study, we examine introductory physics students’ ability to perform analogical reasoning between two isomorphic problems which employ the same underlying physics principles but have different surface features. Three hundred sixty-two students from a calculus-based and an algebra-based introductory physics course were given a quiz in the recitation in which they had to first learn from a solved problem provided and take advantage of what they learned from it to solve another problem (which we call the quiz problem) which was isomorphic. Previous research suggests that the multiple-concept quiz problem is challenging for introductory students. Students in different recitation classes received different interventions in order to help them discern and exploit the underlying similarities of the isomorphic solved and quiz problems. We also conducted think-aloud interviews with four introductory students in order to understand in depth the difficulties they had and explore strategies to provide better scaffolding. We found that most students were able to learn from the solved problem to some extent with the scaffolding provided and invoke the relevant principles in the quiz problem. However, they were not necessarily able to apply the principles correctly. Research suggests that more scaffolding is needed to help students in applying these principles appropriately. We outline a few possible strategies for future investigation.

Similarly shaped letters evoke similar colors in grapheme-color synesthesia.

Science.gov (United States)

Brang, David; Rouw, Romke; Ramachandran, V S; Coulson, Seana

2011-04-01

Grapheme-color synesthesia is a neurological condition in which viewing numbers or letters (graphemes) results in the concurrent sensation of color. While the anatomical substrates underlying this experience are well understood, little research to date has investigated factors influencing the particular colors associated with particular graphemes or how synesthesia occurs developmentally. A recent suggestion of such an interaction has been proposed in the cascaded cross-tuning (CCT) model of synesthesia, which posits that in synesthetes connections between grapheme regions and color area V4 participate in a competitive activation process, with synesthetic colors arising during the component-stage of grapheme processing. This model more directly suggests that graphemes sharing similar component features (lines, curves, etc.) should accordingly activate more similar synesthetic colors. To test this proposal, we created and regressed synesthetic color-similarity matrices for each of 52 synesthetes against a letter-confusability matrix, an unbiased measure of visual similarity among graphemes. Results of synesthetes' grapheme-color correspondences indeed revealed that more similarly shaped graphemes corresponded with more similar synesthetic colors, with stronger effects observed in individuals with more intense synesthetic experiences (projector synesthetes). These results support the CCT model of synesthesia, implicate early perceptual mechanisms as driving factors in the elicitation of synesthetic hues, and further highlight the relationship between conceptual and perceptual factors in this phenomenon. Copyright © 2011 Elsevier Ltd. All rights reserved.

Gambling frequency, gambling problems and concerned significant others of problem gamblers in Finland: cross-sectional population studies in 2007 and 2011.

Science.gov (United States)

Salonen, Anne H; Alho, Hannu; Castrén, Sari

2015-05-01

This study compares past-year gambling frequency, gambling problems and concerned significant others (CSOs) of problem gamblers in Finland by age, from 2007 and 2011. We used random sample data collected in 2007 (n = 4722) and 2011 (n = 4484). The data were weighted, based on gender, age and region of residence. We measured the past-year gambling frequency using a categorical variable, while gambling severity was measured with the South Oaks Gambling Screen. We identified CSOs by a single question including seven response options. Chi-Squared and Fisher's exact tests were used. Overall, the past-year gambling frequency change was statistically significant between 2007 and 2011. Among 18-64-year-old Finnish people, the proportion of non-gamblers decreased. Yet, among 15-17-year-old respondents, non-gambling increased and gambling problems decreased. Among 18-24 year olds, the proportion of close ones with gambling problems also decreased. On the other hand, the proportion of family members with gambling problems increased among the 50-64 year olds. The increase in adult gambling participation was mainly explained by infrequent gambling. The proportion of gambling problems from the gamblers' and CSOs' perspective remained unchanged, yet significant changes were observed within age groups. The short-term changes in under-age gambling problems were desirable. Future studies should explore the adaptation and access hypotheses alongside gambling problems. © 2015 the Nordic Societies of Public Health.

Driving clinical study efficiency by using a productivity breakdown model: comparative evaluation of a global clinical study and a similar Japanese study.

Science.gov (United States)

Takahashi, K; Sengoku, S; Kimura, H

2011-02-01

A fundamental management imperative of pharmaceutical companies is to contain surging costs of developing and launching drugs globally. Clinical studies are a research and development (R&D) cost driver. The objective of this study was to develop a productivity breakdown model, or a key performance indicator (KPI) tree, for an entire clinical study and to use it to compare a global clinical study with a similar Japanese study. We, thereby, hope to identify means of improving study productivity. We developed the new clinical study productivity breakdown model, covering operational aspects and cost factors. Elements for improving clinical study productivity were assessed from a management viewpoint by comparing empirical tracking data from a global clinical study with a Japanese study with similar protocols. The following unique and material differences, beyond simple international difference in cost of living, that could affect the efficiency of future clinical trials were identified: (i) more frequent site visits in the Japanese study, (ii) head counts at the Japanese study sites more than double those of the global study and (iii) a shorter enrollment time window of about a third that of the global study at the Japanese study sites. We identified major differences in the performance of the two studies. These findings demonstrate the potential of the KPI tree for improving clinical study productivity. Trade-offs, such as those between reduction in head count at study sites and expansion of the enrollment time window, must be considered carefully. © 2010 Blackwell Publishing Ltd.

Accident data study of concrete construction companies' similarities and differences between qualified and non-qualified workers in Spain.

Science.gov (United States)

López-Arquillos, Antonio; Rubio-Romero, Juan Carlos; Gibb, Alistair

2015-01-01

The aim of this paper is to discuss findings from an analysis of accidents in concrete construction companies in Spain and to compare the accident rates of qualified and non-qualified workers. A total of 125,021 accidents between 2003 and 2008 involving both blue-collar and white-collar workers were analysed, comparing the variables of occupation, age, company staff, length of service, location of the accident, together with the severity of the accidents. Results showed that lack of experience in the first month is more significant in non-qualified workers and experienced supervisors and that head injuries are more likely to lead to fatalities. The most remarkable similarity was that fatal accidents to and from the worksite are a problem common to both groups of workers.

Pleasures of the Mind: What Makes Jokes and Insight Problems Enjoyable

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Carla Canestrari

2018-01-01

Full Text Available In this paper, a parallel analysis of the enjoyment derived from humor and insight problem solving is presented with reference to a “general” Theory of the Pleasures of the Mind (TPM (Kubovy, 1999 rather than to “local” theories regarding what makes humor and insight problem solving enjoyable. The similarity of these two cognitive activities has already been discussed in previous literature in terms of the cognitive mechanisms which underpin getting a joke or having an insight experience in a problem solving task. The paper explores whether we can learn something new about the similarities and differences between humor and problem solving by means of an investigation of what makes them pleasurable. In the first part of the paper, the framework for this joint analysis is set. Two descriptive studies are then presented in which the participants were asked to report on their experiences relating to solving visuo-spatial insight problems (Study 1 or understanding cartoons (Study 2 in terms of whether they were enjoyable or otherwise. In both studies, the responses were analyzed with reference to a set of categories inspired by the TPM. The results of Study 1 demonstrate that finding the solution to a problem is associated with a positive evaluation, and the most frequent explanations for this were reported as being Curiosity, Virtuosity and Violation of expectations. The results of Study 2 suggest that understanding a joke (Joy of verification and being surprised by it (Feeling of surprise were two essential conditions: when they were not present, the cartoons were perceived as not enjoyable. However, this was not enough to explain the motivations for the choice of the most enjoyable cartoons. Recognizing a Violation of expectations and experiencing a Diminishment in the cleverness or awareness initially attributed to the characters in the cartoon were the aspects which were most frequently indicated by the participants to explain why they

Categorization of Quantum Mechanics Problems by Professors and Students

Science.gov (United States)

Lin, Shih-Yin; Singh, Chandralekha

2010-01-01

We discuss the categorization of 20 quantum mechanics problems by physics professors and undergraduate students from two honours-level quantum mechanics courses. Professors and students were asked to categorize the problems based upon similarity of solution. We also had individual discussions with professors who categorized the problems. Faculty…

Investigating Correlation between Protein Sequence Similarity and Semantic Similarity Using Gene Ontology Annotations.

Science.gov (United States)

Ikram, Najmul; Qadir, Muhammad Abdul; Afzal, Muhammad Tanvir

2018-01-01

Sequence similarity is a commonly used measure to compare proteins. With the increasing use of ontologies, semantic (function) similarity is getting importance. The correlation between these measures has been applied in the evaluation of new semantic similarity methods, and in protein function prediction. In this research, we investigate the relationship between the two similarity methods. The results suggest absence of a strong correlation between sequence and semantic similarities. There is a large number of proteins with low sequence similarity and high semantic similarity. We observe that Pearson's correlation coefficient is not sufficient to explain the nature of this relationship. Interestingly, the term semantic similarity values above 0 and below 1 do not seem to play a role in improving the correlation. That is, the correlation coefficient depends only on the number of common GO terms in proteins under comparison, and the semantic similarity measurement method does not influence it. Semantic similarity and sequence similarity have a distinct behavior. These findings are of significant effect for future works on protein comparison, and will help understand the semantic similarity between proteins in a better way.

The Role of Parenting Stress in Discrepancies between Parent and Teacher Ratings of Behavior Problems in Young Children with Autism Spectrum Disorder

Science.gov (United States)

Reed, Phil; Osborne, Lisa A.

2013-01-01

The study assessed whether teacher and parent ratings of child behavior problems were similar for children with autism spectrum disorders. Two informants rated child behaviors in the same home environment, and the degree to which parenting stress impacted the similarity of the ratings was assessed. Overall behavior problem ratings did not differ…

Predicting the performance of fingerprint similarity searching.

Science.gov (United States)

Vogt, Martin; Bajorath, Jürgen

2011-01-01

Fingerprints are bit string representations of molecular structure that typically encode structural fragments, topological features, or pharmacophore patterns. Various fingerprint designs are utilized in virtual screening and their search performance essentially depends on three parameters: the nature of the fingerprint, the active compounds serving as reference molecules, and the composition of the screening database. It is of considerable interest and practical relevance to predict the performance of fingerprint similarity searching. A quantitative assessment of the potential that a fingerprint search might successfully retrieve active compounds, if available in the screening database, would substantially help to select the type of fingerprint most suitable for a given search problem. The method presented herein utilizes concepts from information theory to relate the fingerprint feature distributions of reference compounds to screening libraries. If these feature distributions do not sufficiently differ, active database compounds that are similar to reference molecules cannot be retrieved because they disappear in the "background." By quantifying the difference in feature distribution using the Kullback-Leibler divergence and relating the divergence to compound recovery rates obtained for different benchmark classes, fingerprint search performance can be quantitatively predicted.

Similarities and differences in borderline and organic personality disorder.

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Mathiesen, Birgit B; Simonsen, Erik; Soegaard, Ulf; Kvist, Kajsa

2014-01-01

Previous research has shown that brain injury patients with Organic Personality Disorder (OPD) may display "borderline" traits due to prefrontal damage, and their personality structure may be unstable and close to a borderline personality organisation. They may have few general neuropsychological dysfunctions but specific executive deficits. Similar deficits have been found in patients with Borderline Personality Disorder (BPD). The objective of this study was to identify differences and similarities between the neuropsychological and personality profiles of BPD and OPD patients. Twenty BPD patients and 24 OPD patients were assessed with the Structured Clinical Interview for DSM-IV Axis II Disorders (SCID-II), the Karolinska Psychodynamic Profile (KAPP), and a comprehensive neuropsychological test battery. Very few neuropsychological differences were found between the two patient groups. However, the verbal fluency, verbal intelligence, verbal memory, and immediate auditory memory/attention of the BPD patients were significantly poorer than the OPD patients'. The KAPP profiles of the BPD patients showed significantly poorer functioning in three areas: frustration tolerance, the body as a factor of self-esteem, and overall personality organisation. These results support our clinical experience and expectations concerning the severity of symptoms of both patient groups. We suggest considering in depth assessments of both neuropsychological and personality-related problems for each of these patients in order to inform treatment.

Integrating Study Skills and Problem Solving into Remedial Mathematics

Science.gov (United States)

Cornick, Jonathan; Guy, G. Michael; Beckford, Ian

2015-01-01

Students at a large urban community college enrolled in seven classes of an experimental remedial algebra programme, which integrated study skills instruction and collaborative problem solving. A control group of seven classes was taught in a traditional lecture format without study skills instruction. Student performance in the course was…

Radiation transformation studies: are they relevant to radiation protection problems?

International Nuclear Information System (INIS)

Seymour, C.B.; Mothersill, C.

1988-01-01

Because of the difficulties of studying radio-carcinogenesis in humans, several in vitro systems are utilised. These cell transformation systems are reviewed, with particular emphasis on their relevance to human radiological protection problems. Most available systems use rodent fibroblasts. These are discussed in detail. Attention is drawn to certain artefacts which can cause problems with interpretation of such data. The relevance of these systems is questionable because of species differences, particularly concerning life span and because most human tumours are derived from epithelial cells. New epithelial culture systems and three-dimensional tissue culture methods becoming available are discussed in the light of their potential for addressing radiation protection problems. (author)

New Similarity Functions

DEFF Research Database (Denmark)

Yazdani, Hossein; Ortiz-Arroyo, Daniel; Kwasnicka, Halina

2016-01-01

spaces, in addition to their similarity in the vector space. Prioritized Weighted Feature Distance (PWFD) works similarly as WFD, but provides the ability to give priorities to desirable features. The accuracy of the proposed functions are compared with other similarity functions on several data sets....... Our results show that the proposed functions work better than other methods proposed in the literature....

The concerned significant others of people with gambling problems in a national representative sample in Sweden - a 1 year follow-up study.

Science.gov (United States)

Svensson, Jessika; Romild, Ulla; Shepherdson, Emma

2013-11-21

Research into the impact of problem gambling on close social networks is scarce with the majority of studies only including help-seeking populations. To date only one study has examined concerned significant others (CSOs) from an epidemiological perspective and it did not consider gender. The aim of this study is to examine the health, social support, and financial situations of CSOs in a Swedish representative sample and to examine gender differences. A population study was conducted in Sweden in 2008/09 (n = 15,000, response rate 63%). Respondents were defined as CSOs if they reported that someone close to them currently or previously had problems with gambling. The group of CSOs was further examined in a 1-year follow up (weighted response rate 74% from the 8,165 respondents in the original sample). Comparisons were also made between those defined as CSOs only at baseline (47.7%, n = 554) and those defined as CSOs at both time points. In total, 18.2% of the population were considered CSOs, with no difference between women and men. Male and female CSOs experienced, to a large extent, similar problems including poor mental health, risky alcohol consumption, economic hardship, and arguments with those closest to them. Female CSOs reported less social support than other women and male CSOs had more legal problems and were more afraid of losing their jobs than other men. One year on, several problems remained even if some improvements were found. Both male and female CSOs reported more negative life events in the 1 year follow-up. Although some relationships are unknown, including between the CSOs and the individuals with gambling problems and the causal relationships between being a CSO and the range of associated problems, the results of this study indicate that gambling problems not only affect the gambling individual and their immediate close family but also the wider social network. A large proportion of the population can be defined as a CSO, half of whom are

City personification as problem solving to strengthen the wholeness of the city: study case in Serui city, Papua

Science.gov (United States)

Hardine, Y. R. I.; Herlily

2018-03-01

Serui City in Papua Province has many unique characters and must be maintained for the sake of the continuity of its identity. However, this city still lacks the facility and depend on other areas. Accordingly, it becomes vulnerable. The wholeness of the city is not just by having strong character but also having strength regarding vitality. The loss of it can affect the character and even eliminate it. Cities and people have many similarities regarding character and vitality. Therefore, there is a chance to solve the problems in the city using the similar approach to treat the human. We called city personification methods as problem-solving to the city. It means that we treat the city as a human being so that the problem can be solved as the human’s treatment. The personification of this city is conducted because of the many treatments that have proven effective in humans and may also be powerful to manifest in city. The personification makes the design will only focus on the particular networks and not on the whole “body,” remain in the hope for strengthening (maintain and improve) the quality of wholeness (character and vitality) city which in this case is Serui.

Sequenced Integration and the Identification of a Problem-Solving Approach through a Learning Process

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Cormas, Peter C.

2016-01-01

Preservice teachers (N = 27) in two sections of a sequenced, methodological and process integrated mathematics/science course solved a levers problem with three similar learning processes and a problem-solving approach, and identified a problem-solving approach through one different learning process. Similar learning processes used included:…

Effect of scaffolding on helping introductory physics students solve quantitative problems involving strong alternative conceptions

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Lin, Shih-Yin; Singh, Chandralekha

2015-12-01

It is well known that introductory physics students often have alternative conceptions that are inconsistent with established physical principles and concepts. Invoking alternative conceptions in the quantitative problem-solving process can derail the entire process. In order to help students solve quantitative problems involving strong alternative conceptions correctly, appropriate scaffolding support can be helpful. The goal of this study is to examine how different scaffolding supports involving analogical problem-solving influence introductory physics students' performance on a target quantitative problem in a situation where many students' solution process is derailed due to alternative conceptions. Three different scaffolding supports were designed and implemented in calculus-based and algebra-based introductory physics courses involving 410 students to evaluate the level of scaffolding needed to help students learn from an analogical problem that is similar in the underlying principles involved but for which the problem-solving process is not derailed by alternative conceptions. We found that for the quantitative problem involving strong alternative conceptions, simply guiding students to work through the solution of the analogical problem first was not enough to help most students discern the similarity between the two problems. However, if additional scaffolding supports that directly helped students examine and repair their knowledge elements involving alternative conceptions were provided, e.g., by guiding students to contemplate related issues and asking them to solve the targeted problem on their own first before learning from the analogical problem provided, students were more likely to discern the underlying similarities between the problems and avoid getting derailed by alternative conceptions when solving the targeted problem. We also found that some scaffolding supports were more effective in the calculus-based course than in the algebra

Froude number fractions to increase walking pattern dynamic similarities: application to plantar pressure study in healthy subjects.

Science.gov (United States)

Moretto, P; Bisiaux, M; Lafortune, M A

2007-01-01

The purpose of this study was to determine if using similar walking velocities obtained from fractions of the Froude number (N(Fr)) and leg length can lead to kinematic and kinetic similarities and lower variability. Fifteen male subjects walked on a treadmill at 0.83 (VS(1)) and 1.16ms(-1) (VS(2)) and then at two similar velocities (V(Sim27) and V(Sim37)) determined from two fractions of the N(Fr) (0.27 and 0.37) so that the average group velocity remained unchanged in both conditions (VS(1)=V (Sim27)andVS(2)=V (Sim37)). N(Fr) can theoretically be used to determine walking velocities proportional to leg lengths and to establish dynamic similarities between subjects. This study represents the first attempt at using this approach to examine plantar pressure. The ankle and knee joint angles were studied in the sagittal plane and the plantar pressure distribution was assessed with an in-shoe measurement device. The similarity ratios were computed from anthropometric parameters and plantar pressure peaks. Dynamically similar conditions caused a 25% reduction in leg joint angles variation and a 10% significant decrease in dimensionless pressure peak variability on average of five footprint locations. It also lead to heel and under-midfoot pressure peaks proportional to body mass and to an increase in the number of under-forefoot plantar pressure peaks proportional to body mass and/or leg length. The use of walking velocities derived from N(Fr) allows kinematic and plantar pressure similarities between subjects to be observed and leads to a lower inter-subject variability. In-shoe pressure measurements have proven to be valuable for the understanding of lower extremity function. Set walking velocities used for clinical assessment mask the effects of body size and individual gait mechanics. The anthropometric scaling of walking velocities (fraction of N(Fr)) should improve identification of unique walking strategies and pathological foot functions.

GEPSI: A Gene Expression Profile Similarity-Based Identification Method of Bioactive Components in Traditional Chinese Medicine Formula.

Science.gov (United States)

Zhang, Baixia; He, Shuaibing; Lv, Chenyang; Zhang, Yanling; Wang, Yun

2018-01-01

The identification of bioactive components in traditional Chinese medicine (TCM) is an important part of the TCM material foundation research. Recently, molecular docking technology has been extensively used for the identification of TCM bioactive components. However, target proteins that are used in molecular docking may not be the actual TCM target. For this reason, the bioactive components would likely be omitted or incorrect. To address this problem, this study proposed the GEPSI method that identified the target proteins of TCM based on the similarity of gene expression profiles. The similarity of the gene expression profiles affected by TCM and small molecular drugs was calculated. The pharmacological action of TCM may be similar to that of small molecule drugs that have a high similarity score. Indeed, the target proteins of the small molecule drugs could be considered TCM targets. Thus, we identified the bioactive components of a TCM by molecular docking and verified the reliability of this method by a literature investigation. Using the target proteins that TCM actually affected as targets, the identification of the bioactive components was more accurate. This study provides a fast and effective method for the identification of TCM bioactive components.

Similarity and uncertainty analysis of the ALLEGRO MOX core

International Nuclear Information System (INIS)

Vrban, B.; Hascik, J.; Necas, V.; Slugen, V.

2015-01-01

The similarity and uncertainty analysis of the ESNII+ ALLEGRO MOX core has identified specific problems and challenges in the field of neutronic calculations. Similarity assessment identified 9 partly comparable experiments where only one reached ck and E values over 0.9. However the Global Integral Index G remains still low (0.75) and cannot be judge das sufficient. The total uncertainty of calculated k eff induced by XS data is according to our calculation 1.04%. The main contributors to this uncertainty are 239 Pu nubar and 238 U inelastic scattering. The additional margin from uncovered sensitivities was determined to be 0.28%. The identified low number of similar experiments prevents the use of advanced XS adjustment and bias estimation methods. More experimental data are needed and presented results may serve as a basic step in development of necessary critical assemblies. Although exact data are not presented in the paper, faster 44 energy group calculation gives almost the same results in similarity analysis in comparison to more complex 238 group calculation. Finally, it was demonstrated that TSUNAMI-IP utility can play a significant role in the future fast reactor development in Slovakia and in the Visegrad region. Clearly a further Research and Development and strong effort should be carried out in order to receive more complex methodology consisting of more plausible covariance data and related quantities. (authors)

PRA-Code Upgrade to Handle a Generic Problem

International Nuclear Information System (INIS)

Wilson, J. R.

1999-01-01

During the probabilistic risk assessment (PRA) for the proposed Yucca Mountain nuclear waste repository, a problem came up that could not be handled by most PRA computer codes. This problem deals with dependencies between sequential events in time. Two similar scenarios that illustrate this problem are LOOP nonrecovery and sequential wearout failures with units of time. The purpose of this paper is twofold: To explain the problem generically, and to show how the PRA code at the INEEL, SAPHIRE, has been modified to solve this problem correctly

Teaching problem-solving competency in Business Studies at secondary school level

Directory of Open Access Journals (Sweden)

Aloe Meintjes

2015-08-01

Full Text Available The high unemployment rate in South Africa compels potential entrepreneurs to start their own businesses in order to survive. Often this is with little or no formal training or education in entrepreneurship. Since problem recognition and problem-solving are amongst the most crucial competencies required for a successful entrepreneurial career, this study aimed to determine whether the application of an extended curriculum with a strong focus on active learning in a business-simulated set-up will enhance this competency. The performance of a specific group of Grade 11 Business Studies learners in this study was measured, both before and after they had been exposed to such an extended curriculum in different experimental settings (intervention. Assessments were done qualitatively through observations and interviews, and quantitatively, by means of question-based scenarios. The findings revealed that the intervention enhanced learners' entrepreneurial competencies concerning problem recognition and problem-solving considerably. This also contributed to these learners' positive approach towards Business Studies. In this article, it is argued that practical exposure in a business-simulated set-up will not only result in enhanced entrepreneurial proficiency in school learners, but also contribute to an accelerated pace of economic growth and job creation in our country.

A Method for Generating Approximate Similarity Solutions of Nonlinear Partial Differential Equations

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Mazhar Iqbal

2014-01-01

Full Text Available Standard application of similarity method to find solutions of PDEs mostly results in reduction to ODEs which are not easily integrable in terms of elementary or tabulated functions. Such situations usually demand solving reduced ODEs numerically. However, there are no systematic procedures available to utilize these numerical solutions of reduced ODE to obtain the solution of original PDE. A practical and tractable approach is proposed to deal with such situations and is applied to obtain approximate similarity solutions to different cases of an initial-boundary value problem of unsteady gas flow through a semi-infinite porous medium.

Skin problems in ostomy patients: a case-control study of risk factors

DEFF Research Database (Denmark)

Nybaek, Hanne; Bang Knudsen, Dorte; Nørgaard Laursen, Troels

2009-01-01

Skin complications are frequent in ostomy patients and a number of risk factors have been suggested. The data on risk factors have, however, been documented mainly in single-centre studies and the actual importance of the suggested risk factors should therefore be verified in a group of ostomy...... patients broadly selected from the gene-ral population. All patients with permanent ostomies living in Roskilde County, Denmark, were invited to participate in the study. A total of 338 responded and 199 agreed to participate. Forty-five percent of all patients presented a skin problem. Less than half (43......%) of patients with a skin problem were aware of the skin problems, and less than 1 in 5 (16%) had sought treatment for their skin problem. Ileostomies, ostomies with leakage and ostomies in patients with body mass index >30 were associated with skin problems. In conclusion, ileostomy, leakage and obesity...

Walking on a user similarity network towards personalized recommendations.

Directory of Open Access Journals (Sweden)

Mingxin Gan

Full Text Available Personalized recommender systems have been receiving more and more attention in addressing the serious problem of information overload accompanying the rapid evolution of the world-wide-web. Although traditional collaborative filtering approaches based on similarities between users have achieved remarkable success, it has been shown that the existence of popular objects may adversely influence the correct scoring of candidate objects, which lead to unreasonable recommendation results. Meanwhile, recent advances have demonstrated that approaches based on diffusion and random walk processes exhibit superior performance over collaborative filtering methods in both the recommendation accuracy and diversity. Building on these results, we adopt three strategies (power-law adjustment, nearest neighbor, and threshold filtration to adjust a user similarity network from user similarity scores calculated on historical data, and then propose a random walk with restart model on the constructed network to achieve personalized recommendations. We perform cross-validation experiments on two real data sets (MovieLens and Netflix and compare the performance of our method against the existing state-of-the-art methods. Results show that our method outperforms existing methods in not only recommendation accuracy and diversity, but also retrieval performance.

Walking on a user similarity network towards personalized recommendations.

Science.gov (United States)

Gan, Mingxin

2014-01-01

Personalized recommender systems have been receiving more and more attention in addressing the serious problem of information overload accompanying the rapid evolution of the world-wide-web. Although traditional collaborative filtering approaches based on similarities between users have achieved remarkable success, it has been shown that the existence of popular objects may adversely influence the correct scoring of candidate objects, which lead to unreasonable recommendation results. Meanwhile, recent advances have demonstrated that approaches based on diffusion and random walk processes exhibit superior performance over collaborative filtering methods in both the recommendation accuracy and diversity. Building on these results, we adopt three strategies (power-law adjustment, nearest neighbor, and threshold filtration) to adjust a user similarity network from user similarity scores calculated on historical data, and then propose a random walk with restart model on the constructed network to achieve personalized recommendations. We perform cross-validation experiments on two real data sets (MovieLens and Netflix) and compare the performance of our method against the existing state-of-the-art methods. Results show that our method outperforms existing methods in not only recommendation accuracy and diversity, but also retrieval performance.

Can goal-free problems facilitating students' flexible thinking?

Science.gov (United States)

Maulidya, Sity Rahmy; Hasanah, Rusi Ulfa; Retnowati, Endah

2017-08-01

Problem solving is the key of doing and also learning mathematics. It takes also the fundamental role of developing mathematical knowledge. Responding to the current reform movement in mathematics, students are expected to learn to be a flexible thinker. The ability to think flexible is challenged by the globalisation, hence influence mathematics education. A flexible thinking includes ability to apply knowledge in different contexts rather than simply use it in similar context when it is studied. Arguably problem solving activities can contribute to the development of the ability to apply skills to unfamiliar situations. Accordingly, an appropriate classroom instructional strategy must be developed. A cognitive load theory suggests that by reducing extraneous cognitive load during learning could enhance transfer learning. A goal-free problem strategy that is developed based in cognitive load theory have been showed to be effective for transfer learning. This strategy enables students to learn a large numbers of problem solving moves from a mathematics problem. The instruction in a goal-free problem directs students to `calculate as many solution as you can' rather than to calculate a single given goal. Many experiment research evident goal-free problem enhance learning. This literature review will discuss evidence goal-free problem facilitate students to solve problems flexibly and thus enhance their problem solving skills, including how its implication in the classroom.

Data mining technique for fast retrieval of similar waveforms in Fusion massive databases

Energy Technology Data Exchange (ETDEWEB)

Vega, J. [Asociacion EURATOM/CIEMAT Para Fusion, Madrid (Spain)], E-mail: jesus.vega@ciemat.es; Pereira, A.; Portas, A. [Asociacion EURATOM/CIEMAT Para Fusion, Madrid (Spain); Dormido-Canto, S.; Farias, G.; Dormido, R.; Sanchez, J.; Duro, N. [Departamento de Informatica y Automatica, UNED, Madrid (Spain); Santos, M. [Departamento de Arquitectura de Computadores y Automatica, UCM, Madrid (Spain); Sanchez, E. [Asociacion EURATOM/CIEMAT Para Fusion, Madrid (Spain); Pajares, G. [Departamento de Arquitectura de Computadores y Automatica, UCM, Madrid (Spain)

2008-01-15

Fusion measurement systems generate similar waveforms for reproducible behavior. A major difficulty related to data analysis is the identification, in a rapid and automated way, of a set of discharges with comparable behaviour, i.e. discharges with 'similar' waveforms. Here we introduce a new technique for rapid searching and retrieval of 'similar' signals. The approach consists of building a classification system that avoids traversing the whole database looking for similarities. The classification system diminishes the problem dimensionality (by means of waveform feature extraction) and reduces the searching space to just the most probable 'similar' waveforms (clustering techniques). In the searching procedure, the input waveform is classified in any of the existing clusters. Then, a similarity measure is computed between the input signal and all cluster elements in order to identify the most similar waveforms. The inner product of normalized vectors is used as the similarity measure as it allows the searching process to be independent of signal gain and polarity. This development has been applied recently to TJ-II stellarator databases and has been integrated into its remote participation system.

Personality Traits, Sexual Problems, and Sexual Orientation: An Empirical Study.

Science.gov (United States)

Peixoto, Maria Manuela; Nobre, Pedro

2016-01-01

Personality traits, namely neuroticism, have been suggested as vulnerability factors for the development and maintenance of sexual dysfunction in heterosexual samples. However, no evidence was found regarding homosexual samples. This study aimed to analyze the differences on personality traits between heterosexual and homosexual men and women with and without sexual problems. Participants were 285 individuals (142 men, 143 women) who completed a web-based survey. Participants answered the NEO Five-Factor Inventory, the Brief Symptomatology Inventory, and questions regarding sexual problems. The groups of men and women with and without sexual problems were matched for sociodemographic variables. A 2 (Group) × 2 (Sexual Orientation) multivariate analysis of covariance was conducted separately for each gender. Results indicated a significant main effect for group and for sexual orientation in male and female samples. Men with sexual problems scored higher on neuroticism, whereas women with sexual problems scored higher on neuroticism and lower on extraversion when compared with healthy controls, regardless of sexual orientation. In addition, gay men scored higher on neuroticism and lesbian women scored higher on conscientiousness compared with the heterosexual groups. The present findings emphasize the central role of neuroticism on sexual problems in both men and women regardless of sexual orientation.

Ant Colony Optimization and the Minimum Cut Problem

DEFF Research Database (Denmark)

Kötzing, Timo; Lehre, Per Kristian; Neumann, Frank

2010-01-01

Ant Colony Optimization (ACO) is a powerful metaheuristic for solving combinatorial optimization problems. With this paper we contribute to the theoretical understanding of this kind of algorithm by investigating the classical minimum cut problem. An ACO algorithm similar to the one that was prov...

A prospective study of weight development and behavior problems in toddlers: the Norwegian Mother and Child Cohort Study

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Hagtvet Knut A

2010-10-01

Full Text Available Abstract Background Previous research has suggested that overweight children have a higher risk of behavior problems, but the causal direction of this relationship remains unclear. In a large prospective population study, we investigated whether child behavior problems and body mass index are associated in toddlers and whether overweight is a risk for behavior problems or vice versa. Methods The study was part of the Norwegian Mother and Child Cohort Study. The sample consisted of 10 860 toddlers, followed up to age 36 months. We used data from maternal questionnaires from gestation week 17 and at child ages 18 and 36 months, and data from the Medical Birth Registry of Norway. Child height and weight were assessed at child health stations and recorded by mothers. Behavior problems were assessed using shortened subscales from the Child Behavior Checklist. Statistical analyses were conducted using structural equation modeling. Results Behavior problems in toddlers were not associated with higher body mass index cross-sectionally at either age 18 or 36 months, and there was no indication that behavior problems caused increasing body mass index over time or vice versa. Conclusions The association between behavior problems and body mass index found in older children did not appear in toddlers up to age 36 months. Future studies should focus on the age span from 3 to 6 years, which includes the period of adiposity rebound.

Mathematical problem solving ability of sport students in the statistical study

Science.gov (United States)

Sari, E. F. P.; Zulkardi; Putri, R. I. I.

2017-12-01

This study aims to determine the problem-solving ability of sport students of PGRI Palembang semester V in the statistics course. Subjects in this study were sport students of PGRI Palembang semester V which amounted to 31 people. The research method used is quasi experiment type one case shoot study. Data collection techniques in this study use the test and data analysis used is quantitative descriptive statistics. The conclusion of this study shown that the mathematical problem solving ability of PGRI Palembang sport students of V semester in the statistical course is categorized well with the average of the final test score of 80.3.

Extrapolation of animal radionuclide retention data to man: Use of similarity ratios

International Nuclear Information System (INIS)

Thomas, J.M.; Eberhardt, L.L.

1976-01-01

A major problem in toxicology is the need for testing a myriad possible substances on several animal species as an aid in establishing standards for man. Particular interest in the problem of extrapolation to man is linked to a need for a method of obtaining transfer coefficients in food-chain models of ecosystems. Such a method could circumvent the necessity to test many species and compounds. Because of their particular interest in radioecology, the authors' studies were initiated using radionuclide retention data available in the literature. Since radionuclide retention should be a function of metabolism it follows that direct or indirect measures could be described by a ''power law'' based on body weight of the organism(s). However, when such power laws have been extended to interspecies comparisons the resulting power coefficients are usually substantially less than the value anticipated and seem to be different for each radionuclide. This paper proposes that interspecies comparisons ought to be based on the proportionality coefficient rather than the power parameter of the power function model and have called pairwise comparisons amongst species ''similarity ratios''. Retention data were examined from five non-ruminant species (including man) where several radionuclides with different physical properties were fed. Subsequently an expression was devised whereby an estimate of biological equilibrium level in man could be calculated using similar estimates from experiments using mice, rats or dogs. There are some statistical questions to resolve which have to do with the assumed frequency distribution for estimates of the proportionality coefficient. In addition, repeated use was made of the same data sets. (author)

How do Rumination and Social Problem Solving Intensify Depression? A Longitudinal Study.

Science.gov (United States)

Hasegawa, Akira; Kunisato, Yoshihiko; Morimoto, Hiroshi; Nishimura, Haruki; Matsuda, Yuko

2018-01-01

In order to examine how rumination and social problem solving intensify depression, the present study investigated longitudinal associations among each dimension of rumination and social problem solving and evaluated aspects of these constructs that predicted subsequent depression. A three-wave longitudinal study, with an interval of 4 weeks between waves, was conducted. Japanese university students completed the Beck Depression Inventory-Second Edition, Ruminative Responses Scale, Social Problem-Solving Inventory-Revised Short Version, and Interpersonal Stress Event Scale on three occasions 4 weeks apart ( n  = 284 at Time 1, 198 at Time 2, 165 at Time 3). Linear mixed models were analyzed to test whether each variable predicted subsequent depression, rumination, and each dimension of social problem solving. Rumination and negative problem orientation demonstrated a mutually enhancing relationship. Because these two variables were not associated with interpersonal conflict during the subsequent 4 weeks, rumination and negative problem orientation appear to strengthen each other without environmental change. Rumination and impulsivity/carelessness style were associated with subsequent depressive symptoms, after controlling for the effect of initial depression. Because rumination and impulsivity/carelessness style were not concurrently and longitudinally associated with each other, rumination and impulsive/careless problem solving style appear to be independent processes that serve to intensify depression.

A Similarity Analysis of Audio Signal to Develop a Human Activity Recognition Using Similarity Networks

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Alejandra García-Hernández

2017-11-01

Full Text Available Human Activity Recognition (HAR is one of the main subjects of study in the areas of computer vision and machine learning due to the great benefits that can be achieved. Examples of the study areas are: health prevention, security and surveillance, automotive research, and many others. The proposed approaches are carried out using machine learning techniques and present good results. However, it is difficult to observe how the descriptors of human activities are grouped. In order to obtain a better understanding of the the behavior of descriptors, it is important to improve the abilities to recognize the human activities. This paper proposes a novel approach for the HAR based on acoustic data and similarity networks. In this approach, we were able to characterize the sound of the activities and identify those activities looking for similarity in the sound pattern. We evaluated the similarity of the sounds considering mainly two features: the sound location and the materials that were used. As a result, the materials are a good reference classifying the human activities compared with the location.

Present status and problems of radionuclide studies in emergency cases

International Nuclear Information System (INIS)

Ogawa, Kiyoshi

1983-01-01

Scintigraphy is just right for diagnosing emergency cases due to its noninvasive and simple method, but emergency radionuclide studies have not become practical as a result of difficulty problems. Recently, nuclear medical devices have become easier to use in operations. It is become of this, that I have submitted this report regarding the problems of radionuclide studies in emergency cases. There were 101 cases (1.4 %) out of 7,310 cases for the year period Sept. 1981 - Aug. 1982. The studies consisted of 12 brain imaging cases, 9 plumonary imaging cases, 22 cardiac study cases (cardio-angiography cases 8, 99m-Tc-PYP myocardium imaging cases 12, 201-Tl myocardium imaging cases 2), 12 renal study cases, 11 G.I. blood loss cases, 35 peripheral angiography cases. In the near future, we will have to be ready to perform emergency radionuclide studies if the need arises. (author)

A Study of the Correlation between Computer Games and Adolescent Behavioral Problems.

Science.gov (United States)

Shokouhi-Moqhaddam, Solmaz; Khezri-Moghadam, Noshiravan; Javanmard, Zeinab; Sarmadi-Ansar, Hassan; Aminaee, Mehran; Shokouhi-Moqhaddam, Majid; Zivari-Rahman, Mahmoud

2013-01-01

Today, due to developing communicative technologies, computer games and other audio-visual media as social phenomena, are very attractive and have a great effect on children and adolescents. The increasing popularity of these games among children and adolescents results in the public uncertainties about plausible harmful effects of these games. This study aimed to investigate the correlation between computer games and behavioral problems on male guidance school students. This was a descriptive-correlative study on 384 randomly chosen male guidance school students. They were asked to answer the researcher's questionnaire about computer games and Achenbach's Youth Self-Report (YSR). The Results of this study indicated that there was about 95% direct significant correlation between the amount of playing games among adolescents and anxiety/depression, withdrawn/depression, rule-breaking behaviors, aggression, and social problems. However, there was no statistically significant correlation between the amount of computer game usage and physical complaints, thinking problems, and attention problems. In addition, there was a significant correlation between the students' place of living and their parents' job, and using computer games. Computer games lead to anxiety, depression, withdrawal, rule-breaking behavior, aggression, and social problems in adolescents.

A Study of the Correlation between Computer Games and Adolescent Behavioral Problems

Science.gov (United States)

Shokouhi-Moqhaddam, Solmaz; Khezri-Moghadam, Noshiravan; Javanmard, Zeinab; Sarmadi-Ansar, Hassan; Aminaee, Mehran; Shokouhi-Moqhaddam, Majid; Zivari-Rahman, Mahmoud

2013-01-01

Background Today, due to developing communicative technologies, computer games and other audio-visual media as social phenomena, are very attractive and have a great effect on children and adolescents. The increasing popularity of these games among children and adolescents results in the public uncertainties about plausible harmful effects of these games. This study aimed to investigate the correlation between computer games and behavioral problems on male guidance school students. Methods This was a descriptive-correlative study on 384 randomly chosen male guidance school students. They were asked to answer the researcher's questionnaire about computer games and Achenbach’s Youth Self-Report (YSR). Findings The Results of this study indicated that there was about 95% direct significant correlation between the amount of playing games among adolescents and anxiety/depression, withdrawn/depression, rule-breaking behaviors, aggression, and social problems. However, there was no statistically significant correlation between the amount of computer game usage and physical complaints, thinking problems, and attention problems. In addition, there was a significant correlation between the students’ place of living and their parents’ job, and using computer games. Conclusion Computer games lead to anxiety, depression, withdrawal, rule-breaking behavior, aggression, and social problems in adolescents. PMID:24494157

The interactive effect of paternal problem drinking and maternal problem drinking on adolescent internalizing problems.

Science.gov (United States)

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.

Wounded Healers: A Multistate Study of Licensed Social Workers' Behavioral Health Problems.

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Straussner, Shulamith Lala Ashenberg; Senreich, Evan; Steen, Jeffrey T

2018-04-01

Studies indicate that helping professionals are disproportionately affected by behavioral health problems. Among social workers, the nature and scope of these problems are understudied. This article reports the findings of a 2015 survey of 6,112 licensed social workers in 13 states regarding their problems with mental health; alcohol, tobacco, and other drugs; and gambling. To ascertain whether these problems preceded or developed during their social work careers, the periods of time when these issues were experienced were identified. Results indicate that 40.2 percent of respondents reported mental health problems before becoming social workers, increasing to 51.8 percent during their social work career, with 28 percent currently experiencing such problems. Nearly 10 percent of the sample experienced substance use problems before becoming social workers, decreasing to 7.7 percent during their career. Analyses by race or ethnicity, sex, and age identified between-group differences in the prevalence of these problems. The article concludes with a discussion of the implications for the social work profession.

Exploring Behavioral Sleep Problems in Children With ADHD and Comorbid Autism Spectrum Disorder.

Science.gov (United States)

Thomas, Simone; Lycett, Kate; Papadopoulos, Nicole; Sciberras, Emma; Rinehart, Nicole

2015-12-04

This study (a) compared behavioral sleep problems in children with comorbid ADHD and autism spectrum disorder (ASD) with those with ADHD and (b) examined child/family factors associated with sleep problems. Cross-sectional study comparison of 392 children with a confirmed ADHD diagnosis (ADHD+ASD, n=93, ADHD, n=299) recruited from 21 peadiatric practises in Victoria, Australia. Data were collected from parents. Key measures included the Child Sleep Habits Questionnaire (CSHQ). Children with ADHD + ASD experienced similar levels and types of behavioral sleep problems compared with those with ADHD. In both groups, the presence of co-occurring internalizing and externalizing comorbidities was associated with sleep problems. Sleep problems were also associated with parent age in the ADHD + ASD group and poorer parent mental health in the ADHD group. Findings suggest comorbid ASD is not associated with increased behavioral sleep problems in children with ADHD and that co-occurring internalizing and externalizing comorbidities may flag children in these groups with sleep problems. © The Author(s) 2015.

Similarity-dissimilarity plot for visualization of high dimensional data in biomedical pattern classification.

Science.gov (United States)

Arif, Muhammad

2012-06-01

In pattern classification problems, feature extraction is an important step. Quality of features in discriminating different classes plays an important role in pattern classification problems. In real life, pattern classification may require high dimensional feature space and it is impossible to visualize the feature space if the dimension of feature space is greater than four. In this paper, we have proposed a Similarity-Dissimilarity plot which can project high dimensional space to a two dimensional space while retaining important characteristics required to assess the discrimination quality of the features. Similarity-dissimilarity plot can reveal information about the amount of overlap of features of different classes. Separable data points of different classes will also be visible on the plot which can be classified correctly using appropriate classifier. Hence, approximate classification accuracy can be predicted. Moreover, it is possible to know about whom class the misclassified data points will be confused by the classifier. Outlier data points can also be located on the similarity-dissimilarity plot. Various examples of synthetic data are used to highlight important characteristics of the proposed plot. Some real life examples from biomedical data are also used for the analysis. The proposed plot is independent of number of dimensions of the feature space.

A Study on Problems of Hijras in West Bengal Based on Neutrosophic Cognitive Maps

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Kalyan Mondal

2014-09-01

Full Text Available This paper deals with the problems faced by Hijras in West Bengal in order to find its solutions using neutrosophic cognitive maps. Florentin Smarandache and Vasantha Kandasamy studied neutrosophic cognitive map which is an extension of fuzzy cognitive map by incorporating indeterminacy. Hijras is considered as neither man nor woman in biological point of view. They are in special gender identity (third gender in Indian society. In their daily life, they have to face many of problems in social aspects. Some of the problems namely, absence of social security, education problem, bad habits, health problem, stigma and discrimination, access to information and service problem, violence, Hijra community issues, and sexual behavior problem are considered in this study. Based on the expert’s opinion and the notion of indeterminacy, we formulate neutrosophic cognitive map. Then we studied the effect of two instantaneous state vectors separately on connection matrix E and neutrosophic adjacency matrix N(E.

Seleucid, Demotic and Mediterranean mathematics versus Chapters VIII and IX of the Nine Chapters: accidental or significant similarities?

DEFF Research Database (Denmark)

Høyrup, Jens

Similarities of geometrical diagrams and arithmetical structures of problems have often been taken as evidence of transmission of mathematical knowledge or techniques between China and “the West”. Confronting on one hand some problems from Chapter VIII of the Nine Chapters with comparable problems...... known from Ancient Greek sources, on the other a Seleucid collection of problems about rectangles with a subset of the triangle problems from Chapter IX, it is concluded, (1) that transmission of some arithmetical riddles without method – not “from Greece” but from a transnational community of traders...

The two-body problem of a pseudo-rigid body and a rigid sphere

DEFF Research Database (Denmark)

Kristiansen, Kristian Uldall; Vereshchagin, M.; Gózdziewski, K.

2012-01-01

n this paper we consider the two-body problem of a spherical pseudo-rigid body and a rigid sphere. Due to the rotational and "re-labelling" symmetries, the system is shown to possess conservation of angular momentum and circulation. We follow a reduction procedure similar to that undertaken...... in the study of the two-body problem of a rigid body and a sphere so that the computed reduced non-canonical Hamiltonian takes a similar form. We then consider relative equilibria and show that the notions of locally central and planar equilibria coincide. Finally, we show that Riemann's theorem on pseudo......-rigid bodies has an extension to this system for planar relative equilibria....

Ethical problems and moral sensitivity in physiotherapy: a descriptive study.

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Kulju, Kati; Suhonen, Riitta; Leino-Kilpi, Helena

2013-08-01

This study identified and described ethical problems encountered by physiotherapists in their practice and physiotherapists' moral sensitivity in ethical situations. A questionnaire-based survey was constructed to identify ethical problems, and the Moral Sensitivity Questionnaire Revised version was used to measure moral sensitivity. Physiotherapists (n = 116) working in public health services responded to the questionnaire. Based on the results, most of the physiotherapists encounter ethical problems weekly. They concern mainly financial considerations, equality and justice, professionalism, unethical conduct of physiotherapists or other professions and patients' self-determination. The dimension of moral strength was emphasised in physiotherapists' self-evaluations of their moral sensitivity. As a conclusion, ethical problems do occur not only at individual level but also at organisational and society level. Physiotherapists seem to have moral strength for speaking on behalf of the patient. Scarce resources make them feel insufficient but much could still be done to provide quality care in co-operation with other health-care professionals.

Virtual drug screen schema based on multiview similarity integration and ranking aggregation.

Science.gov (United States)

Kang, Hong; Sheng, Zhen; Zhu, Ruixin; Huang, Qi; Liu, Qi; Cao, Zhiwei

2012-03-26

The current drug virtual screen (VS) methods mainly include two categories. i.e., ligand/target structure-based virtual screen and that, utilizing protein-ligand interaction fingerprint information based on the large number of complex structures. Since the former one focuses on the one-side information while the later one focuses on the whole complex structure, they are thus complementary and can be boosted by each other. However, a common problem faced here is how to present a comprehensive understanding and evaluation of the various virtual screen results derived from various VS methods. Furthermore, there is still an urgent need for developing an efficient approach to fully integrate various VS methods from a comprehensive multiview perspective. In this study, our virtual screen schema based on multiview similarity integration and ranking aggregation was tested comprehensively with statistical evaluations, providing several novel and useful clues on how to perform drug VS from multiple heterogeneous data sources. (1) 18 complex structures of HIV-1 protease with ligands from the PDB were curated as a test data set and the VS was performed with five different drug representations. Ritonavir ( 1HXW ) was selected as the query in VS and the weighted ranks of the query results were aggregated from multiple views through four similarity integration approaches. (2) Further, one of the ranking aggregation methods was used to integrate the similarity ranks calculated by gene ontology (GO) fingerprint and structural fingerprint on the data set from connectivity map, and two typical HDAC and HSP90 inhibitors were chosen as the queries. The results show that rank aggregation can enhance the result of similarity searching in VS when two or more descriptions are involved and provide a more reasonable similarity rank result. Our study shows that integrated VS based on multiple data fusion can achieve a remarkable better performance compared to that from individual ones and

Female adolescents with severe substance and conduct problems have substantially less brain gray matter volume.

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Manish S Dalwani

Full Text Available Structural neuroimaging studies have demonstrated lower regional gray matter volume in adolescents with severe substance and conduct problems. These research studies, including ours, have generally focused on male-only or mixed-sex samples of adolescents with conduct and/or substance problems. Here we compare gray matter volume between female adolescents with severe substance and conduct problems and female healthy controls of similar ages.Female adolescents with severe substance and conduct problems will show significantly less gray matter volume in frontal regions critical to inhibition (i.e. dorsolateral prefrontal cortex and ventrolateral prefrontal cortex, conflict processing (i.e., anterior cingulate, valuation of expected outcomes (i.e., medial orbitofrontal cortex and the dopamine reward system (i.e. striatum.We conducted whole-brain voxel-based morphometric comparison of structural MR images of 22 patients (14-18 years with severe substance and conduct problems and 21 controls of similar age using statistical parametric mapping (SPM and voxel-based morphometric (VBM8 toolbox. We tested group differences in regional gray matter volume with analyses of covariance, adjusting for age and IQ at p<0.05, corrected for multiple comparisons at whole-brain cluster-level threshold.Female adolescents with severe substance and conduct problems compared to controls showed significantly less gray matter volume in right dorsolateral prefrontal cortex, left ventrolateral prefrontal cortex, medial orbitofrontal cortex, anterior cingulate, bilateral somatosensory cortex, left supramarginal gyrus, and bilateral angular gyrus. Considering the entire brain, patients had 9.5% less overall gray matter volume compared to controls.Female adolescents with severe substance and conduct problems in comparison to similarly aged female healthy controls showed substantially lower gray matter volume in brain regions involved in inhibition, conflict processing, valuation

Image quality assessment based on inter-patch and intra-patch similarity.

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Fei Zhou

Full Text Available In this paper, we propose a full-reference (FR image quality assessment (IQA scheme, which evaluates image fidelity from two aspects: the inter-patch similarity and the intra-patch similarity. The scheme is performed in a patch-wise fashion so that a quality map can be obtained. On one hand, we investigate the disparity between one image patch and its adjacent ones. This disparity is visually described by an inter-patch feature, where the hybrid effect of luminance masking and contrast masking is taken into account. The inter-patch similarity is further measured by modifying the normalized correlation coefficient (NCC. On the other hand, we also attach importance to the impact of image contents within one patch on the IQA problem. For the intra-patch feature, we consider image curvature as an important complement of image gradient. According to local image contents, the intra-patch similarity is measured by adaptively comparing image curvature and gradient. Besides, a nonlinear integration of the inter-patch and intra-patch similarity is presented to obtain an overall score of image quality. The experiments conducted on six publicly available image databases show that our scheme achieves better performance in comparison with several state-of-the-art schemes.

The centroidal algorithm in molecular similarity and diversity calculations on confidential datasets

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Trepalin, Sergey; Osadchiy, Nikolay

2005-09-01

Chemical structure provides exhaustive description of a compound, but it is often proprietary and thus an impediment in the exchange of information. For example, structure disclosure is often needed for the selection of most similar or dissimilar compounds. Authors propose a centroidal algorithm based on structural fragments (screens) that can be efficiently used for the similarity and diversity selections without disclosing structures from the reference set. For an increased security purposes, authors recommend that such set contains at least some tens of structures. Analysis of reverse engineering feasibility showed that the problem difficulty grows with decrease of the screen's radius. The algorithm is illustrated with concrete calculations on known steroidal, quinoline, and quinazoline drugs. We also investigate a problem of scaffold identification in combinatorial library dataset. The results show that relatively small screens of radius equal to 2 bond lengths perform well in the similarity sorting, while radius 4 screens yield better results in diversity sorting. The software implementation of the algorithm taking SDF file with a reference set generates screens of various radii which are subsequently used for the similarity and diversity sorting of external SDFs. Since the reverse engineering of the reference set molecules from their screens has the same difficulty as the RSA asymmetric encryption algorithm, generated screens can be stored openly without further encryption. This approach ensures an end user transfers only a set of structural fragments and no other data. Like other algorithms of encryption, the centroid algorithm cannot give 100% guarantee of protecting a chemical structure from dataset, but probability of initial structure identification is very small-order of 10-40 in typical cases.

Self-similarity and flow characteristics of vertical-axis wind turbine wakes: an LES study

Science.gov (United States)

Abkar, Mahdi; Dabiri, John O.

2017-04-01

Large eddy simulation (LES) is coupled with a turbine model to study the structure of the wake behind a vertical-axis wind turbine (VAWT). In the simulations, a tuning-free anisotropic minimum dissipation model is used to parameterise the subfilter stress tensor, while the turbine-induced forces are modelled with an actuator line technique. The LES framework is first validated in the simulation of the wake behind a model straight-bladed VAWT placed in the water channel and then used to study the wake structure downwind of a full-scale VAWT sited in the atmospheric boundary layer. In particular, the self-similarity of the wake is examined, and it is found that the wake velocity deficit can be well characterised by a two-dimensional multivariate Gaussian distribution. By assuming a self-similar Gaussian distribution of the velocity deficit, and applying mass and momentum conservation, an analytical model is developed and tested to predict the maximum velocity deficit downwind of the turbine. Also, a simple parameterisation of VAWTs for LES with very coarse grid resolutions is proposed, in which the turbine is modelled as a rectangular porous plate with the same thrust coefficient. The simulation results show that, after some downwind distance (x/D ≈ 6), both actuator line and rectangular porous plate models have similar predictions for the mean velocity deficit. These results are of particular importance in simulations of large wind farms where, due to the coarse spatial resolution, the flow around individual VAWTs is not resolved.

A Problem Solving Intervention for hospice caregivers: a pilot study.

Science.gov (United States)

Demiris, George; Oliver, Debra Parker; Washington, Karla; Fruehling, Lynne Thomas; Haggarty-Robbins, Donna; Doorenbos, Ardith; Wechkin, Hope; Berry, Donna

2010-08-01

The Problem Solving Intervention (PSI) is a structured, cognitive-behavioral intervention that provides people with problem-solving coping skills to help them face major negative life events and daily challenges. PSI has been applied to numerous settings but remains largely unexplored in the hospice setting. The aim of this pilot study was to demonstrate the feasibility of PSI targeting informal caregivers of hospice patients. We enrolled hospice caregivers who were receiving outpatient services from two hospice agencies. The intervention included three visits by a research team member. The agenda for each visit was informed by the problem-solving theoretical framework and was customized based on the most pressing problems identified by the caregivers. We enrolled 29 caregivers. Patient's pain was the most frequently identified problem. On average, caregivers reported a higher quality of life and lower level of anxiety postintervention than at baseline. An examination of the caregiver reaction assessment showed an increase of positive esteem average and a decrease of the average value of lack of family support, impact on finances, impact on schedules, and on health. After completing the intervention, caregivers reported lower levels of anxiety, improved problem solving skills, and a reduced negative impact of caregiving. Furthermore, caregivers reported high levels of satisfaction with the intervention, perceiving it as a platform to articulate their challenges and develop a plan to address them. Findings demonstrate the value of problem solving as a psycho-educational intervention in the hospice setting and call for further research in this area.

Study for the design method of multi-agent diagnostic system to improve diagnostic performance for similar abnormality

International Nuclear Information System (INIS)

Minowa, Hirotsugu; Gofuku, Akio

2014-01-01

Accidents on industrial plants cause large loss on human, economic, social credibility. In recent, studies of diagnostic methods using techniques of machine learning such as support vector machine is expected to detect the occurrence of abnormality in a plant early and correctly. There were reported that these diagnostic machines has high accuracy to diagnose the operating state of industrial plant under mono abnormality occurrence. But the each diagnostic machine on the multi-agent diagnostic system may misdiagnose similar abnormalities as a same abnormality if abnormalities to diagnose increases. That causes that a single diagnostic machine may show higher diagnostic performance than one of multi-agent diagnostic system because decision-making considering with misdiagnosis is difficult. Therefore, we study the design method for multi-agent diagnostic system to diagnose similar abnormality correctly. This method aimed to realize automatic generation of diagnostic system where the generation process and location of diagnostic machines are optimized to diagnose correctly the similar abnormalities which are evaluated from the similarity of process signals by statistical method. This paper explains our design method and reports the result evaluated our method applied to the process data of the fast-breeder reactor Monju

Semantic similarity between ontologies at different scales

Energy Technology Data Exchange (ETDEWEB)

Zhang, Qingpeng; Haglin, David J.

2016-04-01

In the past decade, existing and new knowledge and datasets has been encoded in different ontologies for semantic web and biomedical research. The size of ontologies is often very large in terms of number of concepts and relationships, which makes the analysis of ontologies and the represented knowledge graph computational and time consuming. As the ontologies of various semantic web and biomedical applications usually show explicit hierarchical structures, it is interesting to explore the trade-offs between ontological scales and preservation/precision of results when we analyze ontologies. This paper presents the first effort of examining the capability of this idea via studying the relationship between scaling biomedical ontologies at different levels and the semantic similarity values. We evaluate the semantic similarity between three Gene Ontology slims (Plant, Yeast, and Candida, among which the latter two belong to the same kingdom—Fungi) using four popular measures commonly applied to biomedical ontologies (Resnik, Lin, Jiang-Conrath, and SimRel). The results of this study demonstrate that with proper selection of scaling levels and similarity measures, we can significantly reduce the size of ontologies without losing substantial detail. In particular, the performance of Jiang-Conrath and Lin are more reliable and stable than that of the other two in this experiment, as proven by (a) consistently showing that Yeast and Candida are more similar (as compared to Plant) at different scales, and (b) small deviations of the similarity values after excluding a majority of nodes from several lower scales. This study provides a deeper understanding of the application of semantic similarity to biomedical ontologies, and shed light on how to choose appropriate semantic similarity measures for biomedical engineering.

Neutrosophic Refined Similarity Measure Based on Cosine Function

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Said Broumi

2014-12-01

Full Text Available In this paper, the cosine similarity measure of neutrosophic refined (multi- sets is proposed and its properties are studied. The concept of this cosine similarity measure of neutrosophic refined sets is the extension of improved cosine similarity measure of single valued neutrosophic. Finally, using this cosine similarity measure of neutrosophic refined set, the application of medical diagnosis is presented.

Simulation and similarity using models to understand the world

CERN Document Server

Weisberg, Michael

2013-01-01

In the 1950s, John Reber convinced many Californians that the best way to solve the state's water shortage problem was to dam up the San Francisco Bay. Against massive political pressure, Reber's opponents persuaded lawmakers that doing so would lead to disaster. They did this not by empirical measurement alone, but also through the construction of a model. Simulation and Similarity explains why this was a good strategy while simultaneously providing an account of modeling and idealization in modern scientific practice. Michael Weisberg focuses on concrete, mathematical, and computational models in his consideration of the nature of models, the practice of modeling, and nature of the relationship between models and real-world phenomena. In addition to a careful analysis of physical, computational, and mathematical models, Simulation and Similarity offers a novel account of the model/world relationship. Breaking with the dominant tradition, which favors the analysis of this relation through logical notions suc...

A Study of Some General Problems of Dieudonné-Rashevski Type

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Ariana Pitea

2012-01-01

Full Text Available We use a method of investigation based on employing adequate variational calculus techniques in the study of some generalized Dieudonné-Rashevski problems. This approach allows us to state and prove optimality conditions for such kind of vector multitime variational problems, with mixed isoperimetric constraints. We state and prove efficiency conditions and develop a duality theory.

A Challenging Issue in the Etiology of Speech Problems: The Effect of Maternal Exposure to Electromagnetic Fields on Speech Problems in the Offspring

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Zarei S

2015-05-01

Full Text Available Background: Nowadays, mothers are continuously exposed to different sources of electromagnetic fields before and even during pregnancy. It has recently been shown that exposure to mobile phone radiation during pregnancy may lead to adverse effects on the brain development in offspring and cause hyperactivity. Researchers have shown that behavioral problems in laboratory animals which have a similar appearance to ADHD are caused by intrauterine exposure to mobile phones. Objective: The purpose of this study was to investigate whether the maternal exposure to different sources of electromagnetic fields affect on the rate and severity of speech problems in their offspring. Methods: In this study, mothers of 35 healthy 3-5 year old children (control group and 77 children and diagnosed with speech problems who had been referred to a speech treatment center in Shiraz, Iran were interviewed. These mothers were asked whether they had exposure to different sources of electromagnetic fields such as mobile phones, mobile base stations, Wi-Fi, cordless phones, laptops and power lines. Results: We found a significant association between either the call time (P=0.002 or history of mobile phone use (months used and speech problems in the offspring (P=0.003. However, other exposures had no effect on the occurrence of speech problems. To the best of our knowledge, this is the first study to investigate a possible association between maternal exposure to electromagnetic field and speech problems in the offspring. Although a major limitation in our study is the relatively small sample size, this study indicates that the maternal exposure to common sources of electromagnetic fields such as mobile phones can affect the occurrence of speech problems in the offspring.

Disclosure of minor mental health problems: an exploratory theoretical study.

Science.gov (United States)

Williams, B; Healy, D

2001-07-01

The aim of this study was to explore people's experiences, concerns and beliefs about disclosing minor mental health problems by focusing on the ways in which such disclosures are interpreted. Approximately half of people with mental health problems do not seek help. The decision to consult represents just one aspect of the process of revealing one's illness to others. People with mental health problems are known to be reluctant to reveal the existence of those problems through fear of how others might then view them. A qualitative approach was employed. In-depth interviews were carried out with 47 users and nonusers of community mental health services. Interviews were tape-recorded, transcribed and analysed. The data suggest that when people reveal minor mental health problems others interpret these in relation to a number of perceived contextual factors. These include perceptions of the severity and duration of any possible causes, the inner 'strength' of the person, the expected ability of the person to either solve or suppress the experience, and the form and context of the expression itself. The data presented included individuals who were seeking help for relatively 'minor' mental health problems (primarily depression and anxiety) and individuals who had no current mental health problems but routinely managed expressions of their own emotions. Throughout the data there appeared to be no distinct difference between these two groups other than one of the severity of psychological experience. The key elements involved in the interpretation of people's expressions of sadness were essentially the same as those involved in the interpretation of expressions of depression. An appreciation of these contextual factors influencing the interpretation and disclosure of minor mental health problems may aid the development of more person-centred mental health services and inform the content of health education in the mental health field.

Optimization of travel salesman problem using the ant colony system and Greedy search

International Nuclear Information System (INIS)

Esquivel E, J.; Ordonez A, A.; Ortiz S, J. J.

2008-01-01

In this paper we present some results obtained during the development of optimization systems that can be used to design refueling and patterns of control rods in a BWR. These systems use ant colonies and Greedy search. The first phase of this project is to be familiar with these optimization techniques applied to the problem of travel salesman problem (TSP). The utility of TSP study is that, like the refueling design and pattern design of control rods are problems of combinative optimization. Even, the similarity with the problem of the refueling design is remarkable. It is presented some results for the TSP with the 32 state capitals of Mexico country. (Author)

Self-similar pattern formation and continuous mechanics of self-similar systems

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A. V. Dyskin

2007-01-01

Full Text Available In many cases, the critical state of systems that reached the threshold is characterised by self-similar pattern formation. We produce an example of pattern formation of this kind – formation of self-similar distribution of interacting fractures. Their formation starts with the crack growth due to the action of stress fluctuations. It is shown that even when the fluctuations have zero average the cracks generated by them could grow far beyond the scale of stress fluctuations. Further development of the fracture system is controlled by crack interaction leading to the emergence of self-similar crack distributions. As a result, the medium with fractures becomes discontinuous at any scale. We develop a continuum fractal mechanics to model its physical behaviour. We introduce a continuous sequence of continua of increasing scales covering this range of scales. The continuum of each scale is specified by the representative averaging volume elements of the corresponding size. These elements determine the resolution of the continuum. Each continuum hides the cracks of scales smaller than the volume element size while larger fractures are modelled explicitly. Using the developed formalism we investigate the stability of self-similar crack distributions with respect to crack growth and show that while the self-similar distribution of isotropically oriented cracks is stable, the distribution of parallel cracks is not. For the isotropically oriented cracks scaling of permeability is determined. For permeable materials (rocks with self-similar crack distributions permeability scales as cube of crack radius. This property could be used for detecting this specific mechanism of formation of self-similar crack distributions.

Trajectory similarity join in spatial networks

KAUST Repository

Shang, Shuo

2017-09-07

The matching of similar pairs of objects, called similarity join, is fundamental functionality in data management. We consider the case of trajectory similarity join (TS-Join), where the objects are trajectories of vehicles moving in road networks. Thus, given two sets of trajectories and a threshold θ, the TS-Join returns all pairs of trajectories from the two sets with similarity above θ. This join targets applications such as trajectory near-duplicate detection, data cleaning, ridesharing recommendation, and traffic congestion prediction. With these applications in mind, we provide a purposeful definition of similarity. To enable efficient TS-Join processing on large sets of trajectories, we develop search space pruning techniques and take into account the parallel processing capabilities of modern processors. Specifically, we present a two-phase divide-and-conquer algorithm. For each trajectory, the algorithm first finds similar trajectories. Then it merges the results to achieve a final result. The algorithm exploits an upper bound on the spatiotemporal similarity and a heuristic scheduling strategy for search space pruning. The algorithm\\'s per-trajectory searches are independent of each other and can be performed in parallel, and the merging has constant cost. An empirical study with real data offers insight in the performance of the algorithm and demonstrates that is capable of outperforming a well-designed baseline algorithm by an order of magnitude.

Calculus Problem Solving Behavior of Mathematic Education Students

Science.gov (United States)

Rizal, M.; Mansyur, J.

2017-04-01

The purpose of this study is to obtain a description of the problem-solving behaviour of mathematics education students. The attainment of the purpose consisted of several stages: (1) to gain the subject from the mathematic education of first semester students, each of them who has a high, medium, and low competence of mathematic case. (2) To give two mathematical problems with different characteristics. The first problem (M1), the statement does not lead to a resolution. The second problem (M2), a statement leads to problem-solving. (3) To explore the behaviour of problem-solving based on the step of Polya (Rizal, 2011) by way of thinking aloud and in-depth interviews. The obtained data are analysed as suggested by Miles and Huberman (1994) but at first, time triangulation is done or data’s credibility by providing equivalent problem contexts and at different times. The results show that the behavioral problem solvers (mathematic education students) who are capable of high mathematic competency (ST). In understanding M1, ST is more likely to pay attention to an image first, read the texts piecemeal and repeatedly, then as a whole and more focus to the sentences that contain equations, numbers or symbols. As a result, not all information can be received well. When understanding the M2, ST can link the information from a problem that is stored in the working memory to the information on the long-term memory. ST makes planning to the solution of M1 and M2 by using a formula based on similar experiences which have been ever received before. Another case when implementing the troubleshooting plans, ST complete the M1 according to the plan, but not all can be resolved correctly. In contrast to the implementation of the solving plan of M2, ST can solve the problem according to plan quickly and correctly. According to the solving result of M1 and M2, ST conducts by reading the job based on an algorithm and reasonability. Furthermore, when SS and SR understand the

Smoking During Adolescence as a Risk Factor for Attention Problems.

Science.gov (United States)

Treur, Jorien L; Willemsen, Gonneke; Bartels, Meike; Geels, Lot M; van Beek, Jenny H D A; Huppertz, Charlotte; van Beijsterveldt, Catharina E M; Boomsma, Dorret I; Vink, Jacqueline M

2015-11-01

Cigarette smoking and attention-deficit/hyperactivity disorder (ADHD) are highly comorbid. One explanation is that individuals with ADHD use cigarettes as "self-medication" to alleviate their attention problems. However, animal studies reported that exposure to nicotine during adolescence influences the developing brain and negatively affects attention. This is the first human study exploring the effects of smoking during adolescence on attention problems. Longitudinal data on smoking and attention problems were available for 1987 adult and 648 adolescent monozygotic twin pairs from the Netherlands Twin Register. Twin pairs were classified as concordant/discordant for smoking and compared on attention problems. Within adult discordant pairs, the difference in attention problems between the smoking and never-smoking twins was first assessed cross-sectionally. In longitudinal analyses, the increase in attention problems from adolescence, when neither twin smoked, to adulthood was compared within discordant pairs. In subgroups with longitudinal data from childhood and adolescence, changes in smoking concordance and subsequent changes in attention problems were explored. Adult twins who ever smoked reported significantly more attention problems than their never-smoking co-twin. Longitudinal analyses showed a larger increase in attention problems from adolescence to adulthood in smoking twins than their never-smoking co-twin (p adolescence, smoking twins had more attention problems than their never-smoking co-twin, whereas scores were similar before smoking was initiated or after both twins started smoking (not significant in all groups). Results from this genetically informative study suggest smoking during adolescence leads to higher attention problem scores, lasting into adulthood. Copyright © 2015 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.

Discovering Music Structure via Similarity Fusion

DEFF Research Database (Denmark)

for representing music structure is studied in a simplified scenario consisting of 4412 songs and two similarity measures among them. The results suggest that the PLSA model is a useful framework to combine different sources of information, and provides a reasonable space for song representation.......Automatic methods for music navigation and music recommendation exploit the structure in the music to carry out a meaningful exploration of the “song space”. To get a satisfactory performance from such systems, one should incorporate as much information about songs similarity as possible; however...... semantics”, in such a way that all observed similarities can be satisfactorily explained using the latent semantics. Therefore, one can think of these semantics as the real structure in music, in the sense that they can explain the observed similarities among songs. The suitability of the PLSA model...

Discovering Music Structure via Similarity Fusion

DEFF Research Database (Denmark)

Arenas-García, Jerónimo; Parrado-Hernandez, Emilio; Meng, Anders

Automatic methods for music navigation and music recommendation exploit the structure in the music to carry out a meaningful exploration of the “song space”. To get a satisfactory performance from such systems, one should incorporate as much information about songs similarity as possible; however...... semantics”, in such a way that all observed similarities can be satisfactorily explained using the latent semantics. Therefore, one can think of these semantics as the real structure in music, in the sense that they can explain the observed similarities among songs. The suitability of the PLSA model...... for representing music structure is studied in a simplified scenario consisting of 4412 songs and two similarity measures among them. The results suggest that the PLSA model is a useful framework to combine different sources of information, and provides a reasonable space for song representation....

Attention-based image similarity measure with application to content-based information retrieval

Science.gov (United States)

Stentiford, Fred W. M.

2003-01-01

Whilst storage and capture technologies are able to cope with huge numbers of images, image retrieval is in danger of rendering many repositories valueless because of the difficulty of access. This paper proposes a similarity measure that imposes only very weak assumptions on the nature of the features used in the recognition process. This approach does not make use of a pre-defined set of feature measurements which are extracted from a query image and used to match those from database images, but instead generates features on a trial and error basis during the calculation of the similarity measure. This has the significant advantage that features that determine similarity can match whatever image property is important in a particular region whether it be a shape, a texture, a colour or a combination of all three. It means that effort is expended searching for the best feature for the region rather than expecting that a fixed feature set will perform optimally over the whole area of an image and over every image in a database. The similarity measure is evaluated on a problem of distinguishing similar shapes in sets of black and white symbols.

Carbon chain length and the stimulus problem in oldfaction

NARCIS (Netherlands)

Boesveldt, S.; Olsson, M.; Lundstrom, J.N.

2010-01-01

Understanding how odour quality perception is encoded in its molecular properties arguably poses one of the most significant problems in olfaction. Determining the odour structure–quality relationships of structurally similar odorants could provide a key tool to this problem. We tentatively explored

A Cross-Cultural Comparison of Teacher Ratings of Child Adjustment and Behavioral Problems

Science.gov (United States)

Rowe, Ellen W.; Rivers, Lanee; Kamphaus, Randy W.

2013-01-01

This study examines similarities and differences in teacher ratings of behavioral problems and adaptive skills between a sample of 320 students from Anguilla, BWI and 315 children from the United States of America using the Behavior Assessment System for Children (BASC; Reynolds & Kamphaus, 1992). The study also compared teacher ratings of…

Self-similar analysis of the spherical implosion process

International Nuclear Information System (INIS)

Ishiguro, Yukio; Katsuragi, Satoru.

1976-07-01

The implosion processes caused by laser-heating ablation has been studied by self-similarity analysis. Attention is paid to the possibility of existence of the self-similar solution which reproduces the implosion process of high compression. Details of the self-similar analysis are reproduced and conclusions are drawn quantitatively on the gas compression by a single shock. The compression process by a sequence of shocks is discussed in self-similarity. The gas motion followed by a homogeneous isentropic compression is represented by a self-similar motion. (auth.)

Problem Gambling Among Ontario Students: Associations with Substance Abuse, Mental Health Problems, Suicide Attempts, and Delinquent Behaviours.

Science.gov (United States)

Cook, Steven; Turner, Nigel E; Ballon, Bruce; Paglia-Boak, Angela; Murray, Robert; Adlaf, Edward M; Ilie, Gabriela; den Dunnen, Wendy; Mann, Robert E

2015-12-01

This paper describes gambling problems among Ontario students in 2009 and examines the relationship between gambling problems and substance use problems, mental health problem indicators, and delinquent behaviors. Data were derived from the Ontario Student Drug Use and Health Survey of Ontario students in grades 7-12. Gambling problems were measured as 2 or more of 6 indicators of problem gambling. In total 2.8% of the students surveyed endorsed two or more of the problem gambling items. The odds of problem gamblers reporting mental distress was 4.2 times higher than the rest of the sample and the odds of problem gamblers reporting a suicide attempt were 17.8 times greater than the rest of the sample. In addition compared to the rest of the students, delinquent behaviors were also more common among problem gamblers, including theft (OR = 14.5), selling marijuana (OR = 19.6), gang fights (OR = 11.3) and carrying a handgun (OR = 11.2). In a multivariate analysis, substance-use problems, mental health problems, and the participation in a variety of delinquent behaviors remained significantly associated with youth problem gambling behavior. Students who report problem gambling behaviors show increased substance abuse, mental health, and delinquency/criminal problems that are similar to those seen among adult problem gamblers. The association between these problems suggests that these problems could be addressed in a unified manner.

Resource use by two morphologically similar insectivorous bats ...

African Journals Online (AJOL)

Studies of morphologically dissimilar insectivorous bats have lead to the conclusion that morphology is the prime correlate of habitat use, and consequently of diet. This has lead to the prediction that morphologically similar bats should have similar diets. We examined the diet and morphology of two morphologically similar ...

Collaborative Learning in Problem Solving: A Case Study in Metacognitive Learning

Directory of Open Access Journals (Sweden)

Shelly L. Wismath

2015-12-01

Full Text Available Problem solving and collaborative communication are among the key 21st century skills educators want students to develop. This paper presents results from a study of the collaborative work patterns of 133 participants from a university level course designed to develop transferable problem-solving skills. Most of the class time in this course was spent on actually solving puzzles, with minimal direct instruction; students were allowed to work either independently or in small groups of two or more, as they preferred, and to move back and forth between these two modalities as they wished. A distinctive student-driven pattern blending collaborative and independent endeavour was observed, consistently over four course offerings in four years. We discuss a number of factors which appear to be related to this variable pattern of independent and collaborative enterprise, including the thinking and learning styles of the individuals, the preference of the individuals, the types of problems being worked on, and the stage in a given problem at which students were working. We also consider implications of these factors for the teaching of problem solving, arguing that the development of collaborative problem solving abilities is an important metacognitive skill.

Phonological similarity and orthographic similarity affect probed serial recall of Chinese characters.

Science.gov (United States)

Lin, Yi-Chen; Chen, Hsiang-Yu; Lai, Yvonne C; Wu, Denise H

2015-04-01

The previous literature on working memory (WM) has indicated that verbal materials are dominantly retained in phonological representations, whereas other linguistic information (e.g., orthography, semantics) only contributes to verbal WM minimally, if not negligibly. Although accumulating evidence has suggested that multiple linguistic components jointly support verbal WM, the visual/orthographic contribution has rarely been addressed in alphabetic languages, possibly due to the difficulty of dissociating the effects of word forms from the effects of their pronunciations in relatively shallow orthography. In the present study, we examined whether the orthographic representations of Chinese characters support the retention of verbal materials in this language of deep orthography. In Experiments 1a and 2, we independently manipulated the phonological and orthographic similarity of horizontal and vertical characters, respectively, and found that participants' accuracy of probed serial recall was reduced by both similar pronunciations and shared phonetic radicals in the to-be-remembered stimuli. Moreover, Experiment 1b showed that only the effect of phonological, but not that of orthographic, similarity was affected by concurrent articulatory suppression. Taken together, the present results indicate the indispensable contribution of orthographic representations to verbal WM of Chinese characters, and suggest that the linguistic characteristics of a specific language not only determine long-term linguistic-processing mechanisms, but also delineate the organization of verbal WM for that language.

Activation analysis. A basis for chemical similarity and classification

Energy Technology Data Exchange (ETDEWEB)

Beeck, J OP de [Ghent Rijksuniversiteit (Belgium). Instituut voor Kernwetenschappen

1977-01-01

It is shown that activation analysis is especially suited to serve as a basis for determining the chemical similarity between samples defined by their trace-element concentration patterns. The general problem of classification and identification is discussed. The nature of possible classification structures and their appropriate clustering strategies is considered. A practical computer method is suggested and its application as well as the graphical representation of classification results are given. The possibility for classification using information theory is mentioned. Classification of chemical elements is discussed and practically realized after Hadamard transformation of the concentration variation patterns in a series of samples.

Studies on microstructure, mechanical and pitting corrosion behaviour of similar and dissimilar stainless steel gas tungsten arc welds

Science.gov (United States)

Mohammed, Raffi; Dilkush; Srinivasa Rao, K.; Madhusudhan Reddy, G.

2018-03-01

In the present study, an attempt has been made to weld dissimilar alloys of 5mm thick plates i.e., austenitic stainless steel (316L) and duplex stainless steel (2205) and compared with that of similar welds. Welds are made with conventional gas tungsten arc welding (GTAW) process with two different filler wires namely i.e., 309L and 2209. Welds were characterized using optical microscopy to observe the microstructural changes and correlate with mechanical properties using hardness, tensile and impact testing. Potentio-dynamic polarization studies were carried out to observe the pitting corrosion behaviour in different regions of the welds. Results of the present study established that change in filler wire composition resulted in microstructural variation in all the welds with different morphology of ferrite and austenite. Welds made with 2209 filler showed plate like widmanstatten austenite (WA) nucleated at grain boundaries. Compared to similar stainless steel welds inferior mechanical properties was observed in dissimilar stainless steel welds. Pitting corrosion resistance is observed to be low for dissimilar stainless steel welds when compared to similar stainless steel welds. Overall study showed that similar duplex stainless steel welds having favorable microstructure and resulted in better mechanical properties and corrosion resistance. Relatively dissimilar stainless steel welds made with 309L filler obtained optimum combination of mechanical properties and pitting corrosion resistance when compared to 2209 filler and is recommended for industrial practice.

A study on the quantitative model of human response time using the amount and the similarity of information

International Nuclear Information System (INIS)

Lee, Sung Jin

2006-02-01

The mental capacity to retain or recall information, or memory is related to human performance during processing of information. Although a large number of studies have been carried out on human performance, little is known about the similarity effect. The purpose of this study was to propose and validate a quantitative and predictive model on human response time in the user interface with the basic concepts of information amount, similarity and degree of practice. It was difficult to explain human performance by only similarity or information amount. There were two difficulties: constructing a quantitative model on human response time and validating the proposed model by experimental work. A quantitative model based on the Hick's law, the law of practice and similarity theory was developed. The model was validated under various experimental conditions by measuring the participants' response time in the environment of a computer-based display. Human performance was improved by degree of similarity and practice in the user interface. Also we found the age-related human performance which was degraded as he or she was more elder. The proposed model may be useful for training operators who will handle some interfaces and predicting human performance by changing system design

Solving Large Clustering Problems with Meta-Heuristic Search

DEFF Research Database (Denmark)

Turkensteen, Marcel; Andersen, Kim Allan; Bang-Jensen, Jørgen

In Clustering Problems, groups of similar subjects are to be retrieved from data sets. In this paper, Clustering Problems with the frequently used Minimum Sum-of-Squares Criterion are solved using meta-heuristic search. Tabu search has proved to be a successful methodology for solving optimization...... problems, but applications to large clustering problems are rare. The simulated annealing heuristic has mainly been applied to relatively small instances. In this paper, we implement tabu search and simulated annealing approaches and compare them to the commonly used k-means approach. We find that the meta-heuristic...

Self-similar slip distributions on irregular shaped faults

Science.gov (United States)

Herrero, A.; Murphy, S.

2018-06-01

We propose a strategy to place a self-similar slip distribution on a complex fault surface that is represented by an unstructured mesh. This is possible by applying a strategy based on the composite source model where a hierarchical set of asperities, each with its own slip function which is dependent on the distance from the asperity centre. Central to this technique is the efficient, accurate computation of distance between two points on the fault surface. This is known as the geodetic distance problem. We propose a method to compute the distance across complex non-planar surfaces based on a corollary of the Huygens' principle. The difference between this method compared to others sample-based algorithms which precede it is the use of a curved front at a local level to calculate the distance. This technique produces a highly accurate computation of the distance as the curvature of the front is linked to the distance from the source. Our local scheme is based on a sequence of two trilaterations, producing a robust algorithm which is highly precise. We test the strategy on a planar surface in order to assess its ability to keep the self-similarity properties of a slip distribution. We also present a synthetic self-similar slip distribution on a real slab topography for a M8.5 event. This method for computing distance may be extended to the estimation of first arrival times in both complex 3D surfaces or 3D volumes.

Similarity of Symbol Frequency Distributions with Heavy Tails

Directory of Open Access Journals (Sweden)

Martin Gerlach

2016-04-01

Full Text Available Quantifying the similarity between symbolic sequences is a traditional problem in information theory which requires comparing the frequencies of symbols in different sequences. In numerous modern applications, ranging from DNA over music to texts, the distribution of symbol frequencies is characterized by heavy-tailed distributions (e.g., Zipf’s law. The large number of low-frequency symbols in these distributions poses major difficulties to the estimation of the similarity between sequences; e.g., they hinder an accurate finite-size estimation of entropies. Here, we show analytically how the systematic (bias and statistical (fluctuations errors in these estimations depend on the sample size N and on the exponent γ of the heavy-tailed distribution. Our results are valid for the Shannon entropy (α=1, its corresponding similarity measures (e.g., the Jensen-Shanon divergence, and also for measures based on the generalized entropy of order α. For small α’s, including α=1, the errors decay slower than the 1/N decay observed in short-tailed distributions. For α larger than a critical value α^{*}=1+1/γ≤2, the 1/N decay is recovered. We show the practical significance of our results by quantifying the evolution of the English language over the last two centuries using a complete α spectrum of measures. We find that frequent words change more slowly than less frequent words and that α=2 provides the most robust measure to quantify language change.

Self-similar anomalous diffusion and Levy-stable laws

International Nuclear Information System (INIS)

Uchaikin, Vladimir V

2003-01-01

Stochastic principles for constructing the process of anomalous diffusion are considered, and corresponding models of random processes are reviewed. The self-similarity and the independent-increments principles are used to extend the notion of diffusion process to the class of Levy-stable processes. Replacing the independent-increments principle with the renewal principle allows us to take the next step in generalizing the notion of diffusion, which results in fractional-order partial space-time differential equations of diffusion. Fundamental solutions to these equations are represented in terms of stable laws, and their relationship to the fractality and memory of the medium is discussed. A new class of distributions, called fractional stable distributions, is introduced. (reviews of topical problems)

Perceptions of Ideal and Former Partners’ Personality and Similarity

Directory of Open Access Journals (Sweden)

Pieternel Dijkstra

2010-12-01

Full Text Available The present study aimed to test predictions based on both the ‗similarity-attraction‘ hypothesis and the ‗attraction-similarity‘ hypothesis, by studying perceptions of ideal and former partners. Based on the ‗similarity-attraction‘ hypothesis, we expected individuals to desire ideal partners who are similar to the self in personality. In addition, based on the ‗attraction-similarity hypothesis‘, we expected individuals to perceive former partners as dissimilar to them in terms of personality. Findings showed that, whereas the ideal partner was seen as similar to and more positive than the self, the former partner was seen as dissimilar to and more negative than the self. In addition, our study showed that individuals did not rate similarity in personality as very important when seeking a mate. Our findings may help understand why so many relationships end in divorce due to mismatches in personality.

[-25]A Similarity Analysis of Audio Signal to Develop a Human Activity Recognition Using Similarity Networks.

Science.gov (United States)

García-Hernández, Alejandra; Galván-Tejada, Carlos E; Galván-Tejada, Jorge I; Celaya-Padilla, José M; Gamboa-Rosales, Hamurabi; Velasco-Elizondo, Perla; Cárdenas-Vargas, Rogelio

2017-11-21

Human Activity Recognition (HAR) is one of the main subjects of study in the areas of computer vision and machine learning due to the great benefits that can be achieved. Examples of the study areas are: health prevention, security and surveillance, automotive research, and many others. The proposed approaches are carried out using machine learning techniques and present good results. However, it is difficult to observe how the descriptors of human activities are grouped. In order to obtain a better understanding of the the behavior of descriptors, it is important to improve the abilities to recognize the human activities. This paper proposes a novel approach for the HAR based on acoustic data and similarity networks. In this approach, we were able to characterize the sound of the activities and identify those activities looking for similarity in the sound pattern. We evaluated the similarity of the sounds considering mainly two features: the sound location and the materials that were used. As a result, the materials are a good reference classifying the human activities compared with the location.

A comprehensive comparison of network similarities for link prediction and spurious link elimination

Science.gov (United States)

Zhang, Peng; Qiu, Dan; Zeng, An; Xiao, Jinghua

2018-06-01

Identifying missing interactions in complex networks, known as link prediction, is realized by estimating the likelihood of the existence of a link between two nodes according to the observed links and nodes' attributes. Similar approaches have also been employed to identify and remove spurious links in networks which is crucial for improving the reliability of network data. In network science, the likelihood for two nodes having a connection strongly depends on their structural similarity. The key to address these two problems thus becomes how to objectively measure the similarity between nodes in networks. In the literature, numerous network similarity metrics have been proposed and their accuracy has been discussed independently in previous works. In this paper, we systematically compare the accuracy of 18 similarity metrics in both link prediction and spurious link elimination when the observed networks are very sparse or consist of inaccurate linking information. Interestingly, some methods have high prediction accuracy, they tend to perform low accuracy in identification spurious interaction. We further find that methods can be classified into several cluster according to their behaviors. This work is useful for guiding future use of these similarity metrics for different purposes.

Similarity indices I: what do they measure

International Nuclear Information System (INIS)

Johnston, J.W.

1976-11-01

A method for estimating the effects of environmental effusions on ecosystems is described. The characteristics of 25 similarity indices used in studies of ecological communities were investigated. The type of data structure, to which these indices are frequently applied, was described as consisting of vectors of measurements on attributes (species) observed in a set of samples. A general similarity index was characterized as the result of a two-step process defined on a pair of vectors. In the first step an attribute similarity score is obtained for each attribute by comparing the attribute values observed in the pair of vectors. The result is a vector of attribute similarity scores. These are combined in the second step to arrive at the similarity index. The operation in the first step was characterized as a function, g, defined on pairs of attribute values. The second operation was characterized as a function, F, defined on the vector of attribute similarity scores from the first step. Usually, F was a simple sum or weighted sum of the attribute similarity scores. It is concluded that similarity indices should not be used as the test statistic to discriminate between two ecological communities

Similarity indices I: what do they measure.

Energy Technology Data Exchange (ETDEWEB)

Johnston, J.W.

1976-11-01

A method for estimating the effects of environmental effusions on ecosystems is described. The characteristics of 25 similarity indices used in studies of ecological communities were investigated. The type of data structure, to which these indices are frequently applied, was described as consisting of vectors of measurements on attributes (species) observed in a set of samples. A general similarity index was characterized as the result of a two-step process defined on a pair of vectors. In the first step an attribute similarity score is obtained for each attribute by comparing the attribute values observed in the pair of vectors. The result is a vector of attribute similarity scores. These are combined in the second step to arrive at the similarity index. The operation in the first step was characterized as a function, g, defined on pairs of attribute values. The second operation was characterized as a function, F, defined on the vector of attribute similarity scores from the first step. Usually, F was a simple sum or weighted sum of the attribute similarity scores. It is concluded that similarity indices should not be used as the test statistic to discriminate between two ecological communities.

Complications / problems of colostomy in infants and children

International Nuclear Information System (INIS)

Sheikh, M.A.; Akhtar, J.; Ahmed, S.

2006-01-01

To determine the frequency of complications/problems occurring with construction of colostomy in infants and children. All the patients admitted in the unit who required colostomy as part of their management were included in the study. The patients who were operated upon previously or operated elsewhere and referred after having colostomy, were excluded. Problems associated with colostomy construction like skin excoriation and chronic blood loss were also recorded. Chi-square test of proportion was used to determine the p-value. There were 121 patients. Most of the patients were operated due to anorectal malformations (n=71) and Hirschsprung's disease (41). Complications/problems related to colostomy occurred in 67.7% patients. The most common problem was skin excoriation. Second in rating was chronic blood loss from stoma. Prolapse of stoma was more common in transverse loop colostomies. Divided colostomies had higher number of complications as compared to loop colostomies, similarly, transverse colostomies had high number of complications but in both the cases difference was not statistically significant. Four (3.3%) patients died. (author)

New self-similar radiation-hydrodynamics solutions in the high-energy density, equilibrium diffusion limit

International Nuclear Information System (INIS)

Lane, Taylor K; McClarren, Ryan G

2013-01-01

This work presents semi-analytic solutions to a radiation-hydrodynamics problem of a radiation source driving an initially cold medium. Our solutions are in the equilibrium diffusion limit, include material motion and allow for radiation-dominated situations where the radiation energy is comparable to (or greater than) the material internal energy density. As such, this work is a generalization of the classical Marshak wave problem that assumes no material motion and that the radiation energy is negligible. Including radiation energy density in the model serves to slow down the wave propagation. The solutions provide insight into the impact of radiation energy and material motion, as well as present a novel verification test for radiation transport packages. As a verification test, the solution exercises the radiation–matter coupling terms and their v/c treatment without needing a hydrodynamics solve. An example comparison between the self-similar solution and a numerical code is given. Tables of the self-similar solutions are also provided. (paper)

A new similarity index for nonlinear signal analysis based on local extrema patterns

Science.gov (United States)

Niknazar, Hamid; Motie Nasrabadi, Ali; Shamsollahi, Mohammad Bagher

2018-02-01

Common similarity measures of time domain signals such as cross-correlation and Symbolic Aggregate approximation (SAX) are not appropriate for nonlinear signal analysis. This is because of the high sensitivity of nonlinear systems to initial points. Therefore, a similarity measure for nonlinear signal analysis must be invariant to initial points and quantify the similarity by considering the main dynamics of signals. The statistical behavior of local extrema (SBLE) method was previously proposed to address this problem. The SBLE similarity index uses quantized amplitudes of local extrema to quantify the dynamical similarity of signals by considering patterns of sequential local extrema. By adding time information of local extrema as well as fuzzifying quantized values, this work proposes a new similarity index for nonlinear and long-term signal analysis, which extends the SBLE method. These new features provide more information about signals and reduce noise sensitivity by fuzzifying them. A number of practical tests were performed to demonstrate the ability of the method in nonlinear signal clustering and classification on synthetic data. In addition, epileptic seizure detection based on electroencephalography (EEG) signal processing was done by the proposed similarity to feature the potentials of the method as a real-world application tool.

Methods and scales in soil erosion studies in Spain: problems and perspectives

Energy Technology Data Exchange (ETDEWEB)

Garcia-Ruiz, J. M.

2009-07-01

Soil erosion is a major problem in some areas of Spain. Research groups have studied a variety of aspects of this problem indifferent environments, and at a range of scales using a diversity of methods, from piquettes and rainfall simulation to experimental plots, catchment and large regional areas. This has increased knowledge and identified the main problems: farmland abandonment, badlands erosion, the effects of land use changes, and the role of extreme events and erosion in certain crops (particularly vineyards). However, comparison of results among various research groups has been difficult, posing problems in developing solutions from State and Regional administrators. (Author) 73 refs.

Does Problem Behavior Elicit Poor Parenting?: A Prospective Study of Adolescent Girls

Science.gov (United States)

Huh, David; Tristan, Jennifer; Wade, Emily; Stice, Eric

2006-01-01

This study tested the hypothesis that perceived parenting would show reciprocal relations with adolescents' problem behavior using longitudinal data from 496 adolescent girls. Results provided support for the assertion that female problem behavior has an adverse effect on parenting; elevated externalizing symptoms and substance abuse symptoms…

Response inhibition during cue reactivity in problem gamblers: an fMRI study.

Directory of Open Access Journals (Sweden)

Ruth J van Holst

Full Text Available Disinhibition over drug use, enhanced salience of drug use and decreased salience of natural reinforcers are thought to play an important role substance dependence. Whether this is also true for pathological gambling is unclear. To understand the effects of affective stimuli on response inhibition in problem gamblers (PRGs, we designed an affective Go/Nogo to examine the interaction between response inhibition and salience attribution in 16 PRGs and 15 healthy controls (HCs.Four affective blocks were presented with Go trials containing neutral, gamble, positive or negative affective pictures. The No-Go trials in these blocks contained neutral pictures. Outcomes of interest included percentage of impulsive errors and mean reaction times in the different blocks. Brain activity related to No-Go trials was assessed to measure response inhibition in the various affective conditions and brain activity related to Go trials was assessed to measure salience attribution.PRGs made fewer errors during gamble and positive trials than HCs, but were slower during all trials types. Compared to HCs, PRGs activated the dorsolateral prefrontal cortex, anterior cingulate and ventral striatum to a greater extent while viewing gamble pictures. The dorsal lateral and inferior frontal cortex were more activated in PRGs than in HCs while viewing positive and negative pictures. During neutral inhibition, PRGs were slower but similar in accuracy to HCs, and showed more dorsolateral prefrontal and anterior cingulate cortex activity. In contrast, during gamble and positive pictures PRGs performed better than HCs, and showed lower activation of the dorsolateral and anterior cingulate cortex.This study shows that gambling-related stimuli are more salient for PRGs than for HCs. PRGs seem to rely on compensatory brain activity to achieve similar performance during neutral response inhibition. A gambling-related or positive context appears to facilitate response inhibition as

Scaffolding for solving problem in static fluid: A case study

Science.gov (United States)

Koes-H, Supriyono; Muhardjito, Wijaya, Charisma P.

2018-01-01

Problem solving is one of the basic abilities that should be developed from learning physics. However, students still face difficulties in the process of non-routine problem-solving. Efforts are necessary to be taken in order to identify such difficulties and the solutions to solve them. An effort in the form of a diagnosis of students' performance in problem solving can be taken to identify their difficulties, and various instructional scaffolding supports can be utilized to eliminate the difficulties. This case study aimed to describe the students' difficulties in solving static fluid problems and the effort to overcome such difficulties through different scaffolding supports. The research subjects consisted of four 10-grade students of (Public Senior High School) SMAN 4 Malang selected by purposive sampling technique. The data of students' difficulties were collected via think-aloud protocol implemented on students' performance in solving non-routine static fluid problems. Subsequently, combined scaffolding supports were given to the students based on their particular difficulties. The research findings pointed out that there were several conceptual difficulties discovered from the students when solving static fluid problems, i.e. the use of buoyancy force formula, determination of all forces acting on a plane in a fluid, the resultant force on a plane in a fluid, and determination of a plane depth in a fluid. An effort that can be taken to overcome such conceptual difficulties is providing a combination of some appropriate scaffolding supports, namely question prompts with specific domains, simulation, and parallel modeling. The combination can solve students' lack of knowledge and improve their conceptual understanding, as well as help them to find solutions by linking the problems with their prior knowledge. According to the findings, teachers are suggested to diagnose the students' difficulties so that they can provide an appropriate combination of

Workplace bullying, sleep problems and leisure-time physical activity: a prospective cohort study.

Science.gov (United States)

Hansen, Åse Marie; Gullander, Maria; Hogh, Annie; Persson, Roger; Kolstad, Henrik A; Willert, Morten Vejs; Bonde, Jens Peter; Kaerlev, Linda; Rugulies, Reiner; Grynderup, Matias Brødsgaard

2016-01-01

Workplace bullying is a potent stressor that may increase sleep problems. Since physical fitness improves resilience to stress, it seems plausible that recreational physical activities may moderate the association between bullying and sleep. The study aimed to examine prospectively whether (i) bullying increases the risk of sleep problems, and (ii) the association between bullying and sleep problems is moderated by leisure-time physical activity (LTPA). The study sample comprised a cohort of public and private sector employees, who were enrolled into the Work Bullying and Harassment (WBH) cohort (N=3278) or the Psychosocial Risk Factors for Stress and Mental Disease (PRISME) cohort (N=4455). We measured workplace bullying using one question that was preceded by a definition of bullying. We used the Karolinska sleep questionnaire to assess sleep problems. The number of hours per week spent on LTPA estimated the degree of physical activity. Workplace bullying at baseline (T1) was associated with awakening problems and lack of restful sleep at follow-up (T2) but not with overall sleep problems and disturbed sleep. T1-LTPA did not moderate the association between T1-workplace bullying and T2-sleep problems. We found support that workplace bullying is related to development of T2-sleep problems, but this association seems not to be modified by LTPA.

Phoneme Similarity and Confusability

Science.gov (United States)

Bailey, T.M.; Hahn, U.

2005-01-01

Similarity between component speech sounds influences language processing in numerous ways. Explanation and detailed prediction of linguistic performance consequently requires an understanding of these basic similarities. The research reported in this paper contrasts two broad classes of approach to the issue of phoneme similarity-theoretically…

Externalizing problems, attention regulation, and household chaos: a longitudinal behavioral genetic study.

Science.gov (United States)

Wang, Zhe; Deater-Deckard, Kirby; Petrill, Stephen A; Thompson, Lee A

2012-08-01

Previous research documented a robust link between difficulties in self-regulation and development of externalizing problems (i.e., aggression and delinquency). In this study, we examined the longitudinal additive and interactive genetic and environmental covariation underlying this well-established link using a twin design. The sample included 131 pairs of monozygotic twins and 173 pairs of same-sex dizygotic twins who participated in three waves of annual assessment. Mothers and fathers provided reports of externalizing problems. Teacher report and observer rating were used to assess twin's attention regulation. The etiology underlying the link between externalizing problems and attention regulation shifted from a common genetic mechanism to a common environmental mechanism in the transition across middle childhood. Household chaos moderated the genetic variance of and covariance between externalizing problems and attention regulation. The genetic influence on individual differences in both externalizing problems and attention regulation was stronger in more chaotic households. However, higher levels of household chaos attenuated the genetic link between externalizing problems and attention regulation.

University Students' Views on the Perceived Benefits and Drawbacks of Seeking Help for Mental Health Problems on the Internet: A Qualitative Study.

Science.gov (United States)

Chan, Jade Ky; Farrer, Louise M; Gulliver, Amelia; Bennett, Kylie; Griffiths, Kathleen M

2016-01-19

University students experience high levels of mental health problems yet very few seek professional help. Web-based mental health interventions may be useful for the university student population. However, there are few published qualitative studies that have examined the perceived benefits and drawbacks of seeking help for mental health problems on the Internet from the perspective of university students. To investigate the attitudes of university students on mental health help-seeking on the Internet. A total of 19 university students aged 19-24 years participated in 1 of 4 focus groups to examine their views toward help-seeking for mental health problems on the Internet. Perceived concerns about Web-based help-seeking included privacy and confidentiality, difficulty communicating on the Internet, and the quality of Web-based resources. Potential benefits included anonymity/avoidance of stigma, and accessibility. Participants reported mixed views regarding the ability of people with similar mental health issues to interact on the Internet. These factors should be considered in the development of Web-based mental health resources to increase acceptability and engagement from university students.

Are calanco landforms similar to river basins?

Science.gov (United States)

Caraballo-Arias, N A; Ferro, V

2017-12-15

In the past badlands have been often considered as ideal field laboratories for studying landscape evolution because of their geometrical similarity to larger fluvial systems. For a given hydrological process, no scientific proof exists that badlands can be considered a model of river basin prototypes. In this paper the measurements carried out on 45 Sicilian calanchi, a type of badlands that appears as a small-scale hydrographic unit, are used to establish their morphological similarity with river systems whose data are available in the literature. At first the geomorphological similarity is studied by identifying the dimensionless groups, which can assume the same value or a scaled one in a fixed ratio, representing drainage basin shape, stream network and relief properties. Then, for each property, the dimensionless groups are calculated for the investigated calanchi and the river basins and their corresponding scale ratio is evaluated. The applicability of Hack's, Horton's and Melton's laws for establishing similarity criteria is also tested. The developed analysis allows to conclude that a quantitative morphological similarity between calanco landforms and river basins can be established using commonly applied dimensionless groups. In particular, the analysis showed that i) calanchi and river basins have a geometrically similar shape respect to the parameters Rf and Re with a scale factor close to 1, ii) calanchi and river basins are similar respect to the bifurcation and length ratios (λ=1), iii) for the investigated calanchi the Melton number assumes values less than that (0.694) corresponding to the river case and a scale ratio ranging from 0.52 and 0.78 can be used, iv) calanchi and river basins have similar mean relief ratio values (λ=1.13) and v) calanchi present active geomorphic processes and therefore fall in a more juvenile stage with respect to river basins. Copyright © 2017 Elsevier B.V. All rights reserved.

Exploring the Impact of Gambling Advertising: An Interview Study of Problem Gamblers

Science.gov (United States)

Binde, Per

2009-01-01

This study qualitatively explored the impact of gambling advertising on problem gambling by interviewing twenty-five people with current or past gambling problems. Interviews were relatively long and involved the participants' viewing numerous examples of gambling advertising. A quarter of the participants reported that gambling advertising had no…

Scalar Similarity for Relaxed Eddy Accumulation Methods

Science.gov (United States)

Ruppert, Johannes; Thomas, Christoph; Foken, Thomas

2006-07-01

The relaxed eddy accumulation (REA) method allows the measurement of trace gas fluxes when no fast sensors are available for eddy covariance measurements. The flux parameterisation used in REA is based on the assumption of scalar similarity, i.e., similarity of the turbulent exchange of two scalar quantities. In this study changes in scalar similarity between carbon dioxide, sonic temperature and water vapour were assessed using scalar correlation coefficients and spectral analysis. The influence on REA measurements was assessed by simulation. The evaluation is based on observations over grassland, irrigated cotton plantation and spruce forest. Scalar similarity between carbon dioxide, sonic temperature and water vapour showed a distinct diurnal pattern and change within the day. Poor scalar similarity was found to be linked to dissimilarities in the energy contained in the low frequency part of the turbulent spectra ( definition.

Improvement in Generic Problem-Solving Abilities of Students by Use of Tutor-less Problem-Based Learning in a Large Classroom Setting

Science.gov (United States)

Klegeris, Andis; Bahniwal, Manpreet; Hurren, Heather

2013-01-01

Problem-based learning (PBL) was originally introduced in medical education programs as a form of small-group learning, but its use has now spread to large undergraduate classrooms in various other disciplines. Introduction of new teaching techniques, including PBL-based methods, needs to be justified by demonstrating the benefits of such techniques over classical teaching styles. Previously, we demonstrated that introduction of tutor-less PBL in a large third-year biochemistry undergraduate class increased student satisfaction and attendance. The current study assessed the generic problem-solving abilities of students from the same class at the beginning and end of the term, and compared student scores with similar data obtained in three classes not using PBL. Two generic problem-solving tests of equal difficulty were administered such that students took different tests at the beginning and the end of the term. Blinded marking showed a statistically significant 13% increase in the test scores of the biochemistry students exposed to PBL, while no trend toward significant change in scores was observed in any of the control groups not using PBL. Our study is among the first to demonstrate that use of tutor-less PBL in a large classroom leads to statistically significant improvement in generic problem-solving skills of students. PMID:23463230

A local search for a graph clustering problem

Science.gov (United States)

Navrotskaya, Anna; Il'ev, Victor

2016-10-01

In the clustering problems one has to partition a given set of objects (a data set) into some subsets (called clusters) taking into consideration only similarity of the objects. One of most visual formalizations of clustering is graph clustering, that is grouping the vertices of a graph into clusters taking into consideration the edge structure of the graph whose vertices are objects and edges represent similarities between the objects. In the graph k-clustering problem the number of clusters does not exceed k and the goal is to minimize the number of edges between clusters and the number of missing edges within clusters. This problem is NP-hard for any k ≥ 2. We propose a polynomial time (2k-1)-approximation algorithm for graph k-clustering. Then we apply a local search procedure to the feasible solution found by this algorithm and hold experimental research of obtained heuristics.

Prevalence and incidence of mental health problems among Dutch medical students and the study-related and personal risk factors: a longitudinal study.

Science.gov (United States)

Borst, Jorien M; Frings-Dresen, Monique H W; Sluiter, Judith K

2016-11-01

A high prevalence of mental health problems (i.e. depression and/or anxiety) has been found in medical students in comparison with the general population. Therefore, the objective was first to study the prevalence and 1-year incidence of symptoms of depression, anxiety and any mental health problems among Dutch medical students and, second, to study which study-related and personal factors present a risk of these mental health problems. A 1-year prospective longitudinal study was performed among medical students of two medical faculties in the Netherlands (n=951). Health problems and study-related and personal factors were measured with an online questionnaire. Mental health problems were assessed by depression and/or anxiety symptoms (BSI-DEP and BSI-ANG). Univariate and multivariate hierarchical logistic regression analyses were performed to examine which of the study-related and personal factors predict mental health problems. At follow-up, 36%, 28% and 48% of the medical students reported symptoms of depression, anxiety and mental health problems, respectively. The incidence between 2010 and 2011 for depression was 20%, 17% for anxiety and 25% for mental health problems. Students who are worried about their own health during medical education are at an increased risk of future mental health problems (OR 2.0 [1.3-2.9], p=0.00). Excessive drinking behavior is a protective factor in this study (OR 0.7 [0.5-0.9], p=0.02). This study shows that only two out of nine factors are significantly associated with mental health problems among Dutch medical students, one risk factor and one protective factor.

Self-similar regimes of fast ionization waves in shielded discharge tubes

International Nuclear Information System (INIS)

Gerasimov, D.N.; Sinkevich, O.A.

1999-01-01

An analytical self-similar solution to the problem of the propagation of a fast ionization wave (FIW) in a long shielded tube is constructed. An expression determining the influence of the device parameters on the FIW velocity is obtained; the velocity is found to be the nonmonotonic function of the working-gas pressure. The theoretical predictions are compared with the results of experiments carried out with helium and nitrogen. The calculation and experimental results agree within experimental errors

Nuclear markers reveal that inter-lake cichlids' similar morphologies do not reflect similar genealogy.

Science.gov (United States)

Kassam, Daud; Seki, Shingo; Horic, Michio; Yamaoka, Kosaku

2006-08-01

The apparent inter-lake morphological similarity among East African Great Lakes' cichlid species/genera has left evolutionary biologists asking whether such similarity is due to sharing of common ancestor or mere convergent evolution. In order to answer such question, we first used Geometric Morphometrics, GM, to quantify morphological similarity and then subsequently used Amplified Fragment Length Polymorphism, AFLP, to determine if similar morphologies imply shared ancestry or convergent evolution. GM revealed that not all presumed morphological similar pairs were indeed similar, and the dendrogram generated from AFLP data indicated distinct clusters corresponding to each lake and not inter-lake morphological similar pairs. Such results imply that the morphological similarity is due to convergent evolution and not shared ancestry. The congruency of GM and AFLP generated dendrograms imply that GM is capable of picking up phylogenetic signal, and thus GM can be potential tool in phylogenetic systematics.

Student homicidal violence in schools: an international problem.

Science.gov (United States)

Bondü, Rebecca; Cornell, Dewey G; Scheithauer, Herbert

2011-01-01

School homicides have been become a worldwide phenomenon. In the decade following the Columbine shooting there have been at least forty similar events in other countries. This article addresses the international scope of this problem and some of the complex conceptual issues that make student homicidal violence difficult to define and study. Meaningful research on risk and protective factors that can inform evidence-based preventive models is summarized. Copyright © 2011 Wiley Periodicals, Inc., A Wiley Company.

The cross-lagged relationship between father absence and child problem behaviour in the early years.

Science.gov (United States)

Flouri, E; Narayanan, M K; Midouhas, E

2015-11-01

Father absence has negative consequences for children's behaviour. Yet research has not examined how father absence and child behaviour may influence each other. This study models the cross-lagged relationship between father absence (non-residence) and child problem behaviour in the early years. We used data from the UK's Millennium Cohort Study, at children's ages 3, 5 and 7 years (Sweeps 2-4). The sample was 15,293 families in which both biological parents were co-resident at Sweep 1, when the child was aged 9 months. Child problem behaviour was assessed using the clinical cut-offs of the Strengths and Difficulties Questionnaire (SDQ). We also investigated gender differences in the association between father absence and problem behaviour. Father absence at age 3 predicted a higher probability of the child scoring above cut-off for total difficulties at age 5, as did father absence at age 5 for total difficulties at age 7. There were no significant effects for total difficulties on father absence. Similar father absence effects were found for individual SDQ subscales. Using these subscales, we found few child behaviour effects, mostly during the preschool years: children's severe externalizing and social (but not emotional) problems were associated with a greater probability of the father being absent in the next sweep. All cross-lagged relationships were similar for boys and girls. Father absence seems to be mainly the cause rather than the outcome of child problem behaviour in young UK families, and to affect boys and girls similarly. There were some child (mostly externalizing) behaviour effects on father absence, particularly in the early years. © 2015 John Wiley & Sons Ltd.

The cross‐lagged relationship between father absence and child problem behaviour in the early years

Science.gov (United States)

Narayanan, M. K.; Midouhas, E.

2015-01-01

Abstract Background Father absence has negative consequences for children's behaviour. Yet research has not examined how father absence and child behaviour may influence each other. This study models the cross‐lagged relationship between father absence (non‐residence) and child problem behaviour in the early years. Methods We used data from the UK's Millennium Cohort Study, at children's ages 3, 5 and 7 years (Sweeps 2–4). The sample was 15 293 families in which both biological parents were co‐resident at Sweep 1, when the child was aged 9 months. Child problem behaviour was assessed using the clinical cut‐offs of the Strengths and Difficulties Questionnaire (SDQ). We also investigated gender differences in the association between father absence and problem behaviour. Results Father absence at age 3 predicted a higher probability of the child scoring above cut‐off for total difficulties at age 5, as did father absence at age 5 for total difficulties at age 7. There were no significant effects for total difficulties on father absence. Similar father absence effects were found for individual SDQ subscales. Using these subscales, we found few child behaviour effects, mostly during the preschool years: children's severe externalizing and social (but not emotional) problems were associated with a greater probability of the father being absent in the next sweep. All cross‐lagged relationships were similar for boys and girls. Conclusions Father absence seems to be mainly the cause rather than the outcome of child problem behaviour in young UK families, and to affect boys and girls similarly. There were some child (mostly externalizing) behaviour effects on father absence, particularly in the early years. PMID:25708874

Study Of Social Problems And Correlates Of Child Labourers In Slums Of Nagpur

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Ambadekar Nitin N

1998-01-01

Full Text Available Research question: What are the social and work related problems of child labourers? Objectives:1.To study social problems of child labourers. 2. To study some work related problems of child labourers. 3. To study some factors associated with child labourers. Study design: cross sectional study with comparison group. Setting: shivankarnagar & Hasanbagh slums under field practice area of PSM deptt., Govt. Medical College, Nagapur. Participants: 223 child labourers and 223 randomly selected controls from same area aged upto 15 years, sex matched and group matched for age. Results: Prevalence of child labourers in study areas was 21.3%, 43(19.3 females and 180 (80.7% males. Lower socio-economic status, large family size(>6, parental illiteracy and single parenthood were significantly associated with child labour. They were working in varied occupations â€" majority (32.7% being in garage and workshops. Inadequate family income (74.4% and parental compulsion (20.6% were the common reasons cited by child labourers for their jobs â€" school drop â€" outs 173(78.3%, bad habits 56(25.1%, prolonged working hours (mean-8.5+4.5, no holidays and rest hours, inadequate daily wages, verbal (29% & physical abuse (2.7% were the common problems of child labourers, observed in the present study.

Contributions to some cavitation problems in turbomachinery

OpenAIRE

Arakeri, VH

1999-01-01

In the present article, three problems associated with cavitation in turbomachinery are discussed. The first one deals with the potential application of recent understanding in cavitation inception to similar problems in turbomachinery. The second considers the thermodynamic effects in developed cavitation. This has relevance to turbopump operation using fluids other than water. Old correlations to predict the above effect are summarized and a new correlation is proposed. Lastly, the possible...

Siblings versus parents and friends: longitudinal linkages to adolescent externalizing problems

Science.gov (United States)

Defoe, Ivy N; Keijsers, Loes; Hawk, Skyler T; Branje, Susan; Dubas, Judith Semon; Buist, Kirsten; Frijns, Tom; van Aken, Marcel AG; Koot, Hans M; van Lier, Pol AC; Meeus, Wim

2013-01-01

Background: It is well documented that friends’ externalizing problems and negative parent–child interactions predict externalizing problems in adolescence, but relatively little is known about the role of siblings. This four-wave, multi-informant study investigated linkages of siblings’ externalizing problems and sibling–adolescent negative interactions on adolescents’ externalizing problems, while examining and controlling for similar linkages with friends and parents. Methods: Questionnaire data on externalizing problems and negative interactions were annually collected from 497 Dutch adolescents (M = 13.03 years, SD = 0.52, at baseline), as well as their siblings, mothers, fathers, and friends. Results: Cross-lagged panel analyses revealed modest unique longitudinal paths from sibling externalizing problems to adolescent externalizing problems, for male and female adolescents, and for same-sex and mixed-sex sibling dyads, but only from older to younger siblings. Moreover, these paths were above and beyond significant paths from mother–adolescent negative interaction and friend externalizing problems to adolescent externalizing problems, 1 year later. No cross-lagged paths existed between sibling–adolescent negative interaction and adolescent externalizing problems. Conclusions: Taken together, it appears that especially older sibling externalizing problems may be a unique social risk factor for adolescent externalizing problems, equal in strength to significant parents’ and friends’ risk factors. PMID:23398022

The semantic similarity ensemble

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Andrea Ballatore

2013-12-01

Full Text Available Computational measures of semantic similarity between geographic terms provide valuable support across geographic information retrieval, data mining, and information integration. To date, a wide variety of approaches to geo-semantic similarity have been devised. A judgment of similarity is not intrinsically right or wrong, but obtains a certain degree of cognitive plausibility, depending on how closely it mimics human behavior. Thus selecting the most appropriate measure for a specific task is a significant challenge. To address this issue, we make an analogy between computational similarity measures and soliciting domain expert opinions, which incorporate a subjective set of beliefs, perceptions, hypotheses, and epistemic biases. Following this analogy, we define the semantic similarity ensemble (SSE as a composition of different similarity measures, acting as a panel of experts having to reach a decision on the semantic similarity of a set of geographic terms. The approach is evaluated in comparison to human judgments, and results indicate that an SSE performs better than the average of its parts. Although the best member tends to outperform the ensemble, all ensembles outperform the average performance of each ensemble's member. Hence, in contexts where the best measure is unknown, the ensemble provides a more cognitively plausible approach.

Risk of maltreatment for siblings: Factors associated with similar and different childhood experiences in a dyadic sample of adult siblings.

Science.gov (United States)

Witte, Susanne; Fegert, Jörg M; Walper, Sabine

2018-02-01

Siblings share the same environment and thus potentially a substantial number of risk factors for child maltreatment. Furthermore, the number of siblings and the sibling constellation itself might pose a risk for child maltreatment. Little is known about the likelihood that more than one child in a family is maltreated and which factors increase the risk. This study sought to investigate similarities and differences in maltreatment in siblings and risk factors associated with the maltreatment of more than one child from the same family. Data on maltreatment during childhood and adolescence, family background, and sibling constellation were collected from 870 pairs of siblings. In the dyadic analyses, siblings reported similar maltreatment experiences, especially when any type of maltreatment was considered. Parents' mental health problems were significant predictors for maltreatment of at least one sibling. Father's mental health problems were predictive of maltreatment of both or only the younger sibling, mother's mental health problems of both or only the older sibling. Closeness in age and same gender of siblings did not emerge as a consistent predictor. The increasing number of siblings was a risk factor for any type of maltreatment of both siblings. The results highlight the need for preventive measures for families with a large number of children and with parents with mental health problems as well as a repeated risk assessment of all siblings in a family when one sibling was maltreated. Copyright © 2017 Elsevier Ltd. All rights reserved.

Scaling of peak flows with constant flow velocity in random self-similar networks

Science.gov (United States)

Troutman, Brent M.; Mantilla, Ricardo; Gupta, Vijay K.

2011-01-01

A methodology is presented to understand the role of the statistical self-similar topology of real river networks on scaling, or power law, in peak flows for rainfall-runoff events. We created Monte Carlo generated sets of ensembles of 1000 random self-similar networks (RSNs) with geometrically distributed interior and exterior generators having parameters pi and pe, respectively. The parameter values were chosen to replicate the observed topology of real river networks. We calculated flow hydrographs in each of these networks by numerically solving the link-based mass and momentum conservation equation under the assumption of constant flow velocity. From these simulated RSNs and hydrographs, the scaling exponents β and φ characterizing power laws with respect to drainage area, and corresponding to the width functions and flow hydrographs respectively, were estimated. We found that, in general, φ > β, which supports a similar finding first reported for simulations in the river network of the Walnut Gulch basin, Arizona. Theoretical estimation of β and φ in RSNs is a complex open problem. Therefore, using results for a simpler problem associated with the expected width function and expected hydrograph for an ensemble of RSNs, we give heuristic arguments for theoretical derivations of the scaling exponents β(E) and φ(E) that depend on the Horton ratios for stream lengths and areas. These ratios in turn have a known dependence on the parameters of the geometric distributions of RSN generators. Good agreement was found between the analytically conjectured values of β(E) and φ(E) and the values estimated by the simulated ensembles of RSNs and hydrographs. The independence of the scaling exponents φ(E) and φ with respect to the value of flow velocity and runoff intensity implies an interesting connection between unit hydrograph theory and flow dynamics. Our results provide a reference framework to study scaling exponents under more complex scenarios

THE OPINION OF MANAGERS AND TEACHERS ON DISCIPLINE PROBLEMS AT ELEMENTARY SCHOOLS

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Latife KABAKLI ÇİMEN

2015-07-01

Full Text Available This research was conducted to analyse the approach of secondary school teachers to disciplinary problems. The controlled group of the research, which was made with the model of screening, was formed by 240 teachers. The data of the research we re gained by personal data form, which was prepared by the researcher , and reasons of discipline questionnaire designed by Cerci (2009. Collected data was coded and analyzed by SPSS programme. Due to the results of the research; the approach to disciplinary problems of managers and teachers, w ho work in high schools, do not differentiate regarding their sex, whether they hold bachelors or postgraduate degree. The opinions of managers and teachers, who work in secondary schools, regarding disciplinary problems depending on whether they are manag ers or teachers, are similar for 21 out of 24 items and different for 3 items. The opinions of managers and teachers, who work in high schools, regarding disciplinary problems with the variable of what type of school they work, are similar for 20 o ut of 24 items and different for 4 item s, with the variable of age their disciplinary opinions are similar for 22 out of 24 items and different for 2 item s. The opinions of managers and teachers, who work in secondary schools, regarding disciplinary problems with the variable of experience, are similar for 21 out of 24 items and different for 3 item s; with the variable of which school they graduated their disciplinary opinions are similar for 19 out of 24 items and different for 5 item s.

How similar are recognition memory and inductive reasoning?

Science.gov (United States)

Hayes, Brett K; Heit, Evan

2013-07-01

Conventionally, memory and reasoning are seen as different types of cognitive activities driven by different processes. In two experiments, we challenged this view by examining the relationship between recognition memory and inductive reasoning involving multiple forms of similarity. A common study set (members of a conjunctive category) was followed by a test set containing old and new category members, as well as items that matched the study set on only one dimension. The study and test sets were presented under recognition or induction instructions. In Experiments 1 and 2, the inductive property being generalized was varied in order to direct attention to different dimensions of similarity. When there was no time pressure on decisions, patterns of positive responding were strongly affected by property type, indicating that different types of similarity were driving recognition and induction. By comparison, speeded judgments showed weaker property effects and could be explained by generalization based on overall similarity. An exemplar model, GEN-EX (GENeralization from EXamples), could account for both the induction and recognition data. These findings show that induction and recognition share core component processes, even when the tasks involve flexible forms of similarity.

Musculoskeletal Problems Associated with University Students Computer Users: A Cross-Sectional Study

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Rakhadani PB

2017-07-01

Full Text Available While several studies have examined the prevalence and correlates of musculoskeletal problems among university students, scanty information exists in South African context. The objective of this study was to determine the prevalence, causes and consequences of musculoskeletal problems among University of Venda students’ computer users. This cross-sectional study involved 694 university students at the University of Venda. A self-designed questionnaire was used to collect information on the sociodemographic characteristics, problems associated with computer users, and causes of musculoskeletal problems associated with computer users. The majority (84.6% of the participants use computer for internet, wording processing (20.3%, and games (18.7%. The students reported neck pain when using computer (52.3%; shoulder (47.0%, finger (45.0%, lower back (43.1%, general body pain (42.9%, elbow (36.2%, wrist (33.7%, hip and foot (29.1% and knee (26.2%. Reported causes of musculoskeletal pains associated with computer usage were: sitting position, low chair, a lot of time spent on computer, uncomfortable laboratory chairs, and stressfulness. Eye problems (51.9%, muscle cramp (344.0%, headache (45.3%, blurred vision (38.0%, feeling of illness (39.9% and missed lectures (29.1% were consequences of musculoskeletal problems linked to computer use. The majority of students reported having mild pain (43.7%, moderate (24.2%, and severe (8.4% pains. Years of computer use were significantly associated with neck, shoulder and wrist pain. Using computer for internet was significantly associated with neck pain (OR=0.60; 95% CI 0.40-0.93; games: neck (OR=0.60; 95% CI 0.40-0.85 and hip/foot (OR=0.60; CI 95% 0.40-0.92, programming for elbow (OR= 1.78; CI 95% 1.10-2.94 and wrist (OR=2.25; CI 95% 1.36-3.73, while word processing was significantly associated with lower back (OR=1.45; CI 95% 1.03-2.04. Undergraduate study had a significant association with elbow pain (OR=2

Workplace bullying, sleep problems and leisure-time physical activity: a prospective cohort study

DEFF Research Database (Denmark)

Hansen, Åse Marie; Gullander, Maria; Hogh, Annie

2015-01-01

and Harassment (WBH) cohort (N=3278) or the Psychosocial Risk Factors for Stress and Mental Disease (PRISME) cohort (N=4455). We measured workplace bullying using one question that was preceded by a definition of bullying. We used the Karolinska sleep questionnaire to assess sleep problems. The number of hours......OBJECTIVES: Workplace bullying is a potent stressor that may increase sleep problems. Since physical fitness improves resilience to stress, it seems plausible that recreational physical activities may moderate the association between bullying and sleep. The study aimed to examine prospectively...... whether (i) bullying increases the risk of sleep problems, and (ii) the association between bullying and sleep problems is moderated by leisure-time physical activity (LTPA). METHODS: The study sample comprised a cohort of public and private sector employees, who were enrolled into the Work Bullying...

Investigation of psychophysical similarity measures for selection of similar images in the diagnosis of clustered microcalcifications on mammograms

International Nuclear Information System (INIS)

Muramatsu, Chisako; Li Qiang; Schmidt, Robert; Shiraishi, Junji; Doi, Kunio

2008-01-01

The presentation of images with lesions of known pathology that are similar to an unknown lesion may be helpful to radiologists in the diagnosis of challenging cases for improving the diagnostic accuracy and also for reducing variation among different radiologists. The authors have been developing a computerized scheme for automatically selecting similar images with clustered microcalcifications on mammograms from a large database. For similar images to be useful, they must be similar from the point of view of the diagnosing radiologists. In order to select such images, subjective similarity ratings were obtained for a number of pairs of clustered microcalcifications by breast radiologists for establishment of a ''gold standard'' of image similarity, and the gold standard was employed for determination and evaluation of the selection of similar images. The images used in this study were obtained from the Digital Database for Screening Mammography developed by the University of South Florida. The subjective similarity ratings for 300 pairs of images with clustered microcalcifications were determined by ten breast radiologists. The authors determined a number of image features which represent the characteristics of clustered microcalcifications that radiologists would use in their diagnosis. For determination of objective similarity measures, an artificial neural network (ANN) was employed. The ANN was trained with the average subjective similarity ratings as teacher and selected image features as input data. The ANN was trained to learn the relationship between the image features and the radiologists' similarity ratings; therefore, once the training was completed, the ANN was able to determine the similarity, called a psychophysical similarity measure, which was expected to be close to radiologists' impressions, for an unknown pair of clustered microcalcifications. By use of a leave-one-out test method, the best combination of features was selected. The correlation

Investigation of psychophysical similarity measures for selection of similar images in the diagnosis of clustered microcalcifications on mammograms

Energy Technology Data Exchange (ETDEWEB)

Muramatsu, Chisako; Li Qiang; Schmidt, Robert; Shiraishi, Junji; Doi, Kunio [Department of Radiology, University of Chicago, 5841 South Maryland Avenue, Chicago, Illinois 60637 (United States) and Department of Intelligent Image Information, Gifu University, 1-1 Yanagido, Gifu (Japan); Department of Radiology, Duke Advanced Imaging Labs, Duke University, 2424 Erwin Road, Suite 302, Durham, North Carolina 27705 (United States); Department of Radiology, University of Chicago, 5841 South Maryland Avenue, Chicago, Illinois 60637 (United States)

2008-12-15

The presentation of images with lesions of known pathology that are similar to an unknown lesion may be helpful to radiologists in the diagnosis of challenging cases for improving the diagnostic accuracy and also for reducing variation among different radiologists. The authors have been developing a computerized scheme for automatically selecting similar images with clustered microcalcifications on mammograms from a large database. For similar images to be useful, they must be similar from the point of view of the diagnosing radiologists. In order to select such images, subjective similarity ratings were obtained for a number of pairs of clustered microcalcifications by breast radiologists for establishment of a ''gold standard'' of image similarity, and the gold standard was employed for determination and evaluation of the selection of similar images. The images used in this study were obtained from the Digital Database for Screening Mammography developed by the University of South Florida. The subjective similarity ratings for 300 pairs of images with clustered microcalcifications were determined by ten breast radiologists. The authors determined a number of image features which represent the characteristics of clustered microcalcifications that radiologists would use in their diagnosis. For determination of objective similarity measures, an artificial neural network (ANN) was employed. The ANN was trained with the average subjective similarity ratings as teacher and selected image features as input data. The ANN was trained to learn the relationship between the image features and the radiologists' similarity ratings; therefore, once the training was completed, the ANN was able to determine the similarity, called a psychophysical similarity measure, which was expected to be close to radiologists' impressions, for an unknown pair of clustered microcalcifications. By use of a leave-one-out test method, the best combination of features

Nurses' recognition and registration of depression, anxiety and diabetes-specific emotional problems in outpatients with diabetes mellitus

DEFF Research Database (Denmark)

Pouwer, Francois; Beekman, Aartjan T F; Lubach, Caroline

2006-01-01

OBJECTIVE: The aim of this study was to investigate how often emotional problems were recognized and registered by diabetes nurses. METHODS: We studied medical charts and questionnaire data of 112 diabetes patients. The hospital anxiety, depression scale and the problem areas in diabetes survey...... were used to measure anxiety, depression and diabetes-specific emotional distress. RESULTS: In patients with moderate to severe levels of anxiety or depression, the presence of an emotional problem was recorded in the medical chart in 20-25% of the cases. The registration-rate of diabetes......-specific emotional distress was also found to be low, ranging from 0% (treatment-related problems) to 29% (diabetes-related emotional problems). CONCLUSION: Registration-rates of emotional problems by diabetes nurses were found to be low, but quite similar to detection rates of physicians and nurses in studies...

Multicriteria Similarity-Based Anomaly Detection Using Pareto Depth Analysis.

Science.gov (United States)

Hsiao, Ko-Jen; Xu, Kevin S; Calder, Jeff; Hero, Alfred O

2016-06-01

We consider the problem of identifying patterns in a data set that exhibits anomalous behavior, often referred to as anomaly detection. Similarity-based anomaly detection algorithms detect abnormally large amounts of similarity or dissimilarity, e.g., as measured by the nearest neighbor Euclidean distances between a test sample and the training samples. In many application domains, there may not exist a single dissimilarity measure that captures all possible anomalous patterns. In such cases, multiple dissimilarity measures can be defined, including nonmetric measures, and one can test for anomalies by scalarizing using a nonnegative linear combination of them. If the relative importance of the different dissimilarity measures are not known in advance, as in many anomaly detection applications, the anomaly detection algorithm may need to be executed multiple times with different choices of weights in the linear combination. In this paper, we propose a method for similarity-based anomaly detection using a novel multicriteria dissimilarity measure, the Pareto depth. The proposed Pareto depth analysis (PDA) anomaly detection algorithm uses the concept of Pareto optimality to detect anomalies under multiple criteria without having to run an algorithm multiple times with different choices of weights. The proposed PDA approach is provably better than using linear combinations of the criteria, and shows superior performance on experiments with synthetic and real data sets.

Equilibrium problems for Raney densities

Science.gov (United States)

Forrester, Peter J.; Liu, Dang-Zheng; Zinn-Justin, Paul

2015-07-01

The Raney numbers are a class of combinatorial numbers generalising the Fuss-Catalan numbers. They are indexed by a pair of positive real numbers (p, r) with p > 1 and 0 0 and similarly use both methods to identify the equilibrium problem for (p, r) = (θ/q + 1, 1/q), θ > 0 and q \\in Z+ . The Wiener-Hopf method is used to extend the latter to parameters (p, r) = (θ/q + 1, m + 1/q) for m a non-negative integer, and also to identify the equilibrium problem for a family of densities with moments given by certain binomial coefficients.

A shortest-path graph kernel for estimating gene product semantic similarity

Directory of Open Access Journals (Sweden)

Alvarez Marco A

2011-07-01

Full Text Available Abstract Background Existing methods for calculating semantic similarity between gene products using the Gene Ontology (GO often rely on external resources, which are not part of the ontology. Consequently, changes in these external resources like biased term distribution caused by shifting of hot research topics, will affect the calculation of semantic similarity. One way to avoid this problem is to use semantic methods that are "intrinsic" to the ontology, i.e. independent of external knowledge. Results We present a shortest-path graph kernel (spgk method that relies exclusively on the GO and its structure. In spgk, a gene product is represented by an induced subgraph of the GO, which consists of all the GO terms annotating it. Then a shortest-path graph kernel is used to compute the similarity between two graphs. In a comprehensive evaluation using a benchmark dataset, spgk compares favorably with other methods that depend on external resources. Compared with simUI, a method that is also intrinsic to GO, spgk achieves slightly better results on the benchmark dataset. Statistical tests show that the improvement is significant when the resolution and EC similarity correlation coefficient are used to measure the performance, but is insignificant when the Pfam similarity correlation coefficient is used. Conclusions Spgk uses a graph kernel method in polynomial time to exploit the structure of the GO to calculate semantic similarity between gene products. It provides an alternative to both methods that use external resources and "intrinsic" methods with comparable performance.

Conjugate Problems in Convective Heat Transfer: Review

Directory of Open Access Journals (Sweden)

Abram Dorfman

2009-01-01

Full Text Available A review of conjugate convective heat transfer problems solved during the early and current time of development of this modern approach is presented. The discussion is based on analytical solutions of selected typical relatively simple conjugate problems including steady-state and transient processes, thermal material treatment, and heat and mass transfer in drying. This brief survey is accompanied by the list of almost two hundred publications considering application of different more and less complex analytical and numerical conjugate models for simulating technology processes and industrial devices from aerospace systems to food production. The references are combined in the groups of works studying similar problems so that each of the groups corresponds to one of selected analytical solutions considered in detail. Such structure of review gives the reader the understanding of early and current situation in conjugate convective heat transfer modeling and makes possible to use the information presented as an introduction to this area on the one hand, and to find more complicated publications of interest on the other hand.

SpolSimilaritySearch - A web tool to compare and search similarities between spoligotypes of Mycobacterium tuberculosis complex.

Science.gov (United States)

Couvin, David; Zozio, Thierry; Rastogi, Nalin

2017-07-01

Spoligotyping is one of the most commonly used polymerase chain reaction (PCR)-based methods for identification and study of genetic diversity of Mycobacterium tuberculosis complex (MTBC). Despite its known limitations if used alone, the methodology is particularly useful when used in combination with other methods such as mycobacterial interspersed repetitive units - variable number of tandem DNA repeats (MIRU-VNTRs). At a worldwide scale, spoligotyping has allowed identification of information on 103,856 MTBC isolates (corresponding to 98049 clustered strains plus 5807 unique isolates from 169 countries of patient origin) contained within the SITVIT2 proprietary database of the Institut Pasteur de la Guadeloupe. The SpolSimilaritySearch web-tool described herein (available at: http://www.pasteur-guadeloupe.fr:8081/SpolSimilaritySearch) incorporates a similarity search algorithm allowing users to get a complete overview of similar spoligotype patterns (with information on presence or absence of 43 spacers) in the aforementioned worldwide database. This tool allows one to analyze spread and evolutionary patterns of MTBC by comparing similar spoligotype patterns, to distinguish between widespread, specific and/or confined patterns, as well as to pinpoint patterns with large deleted blocks, which play an intriguing role in the genetic epidemiology of M. tuberculosis. Finally, the SpolSimilaritySearch tool also provides with the country distribution patterns for each queried spoligotype. Copyright © 2017 Elsevier Ltd. All rights reserved.

Ethics in scientific communication: study of a problem case.

Science.gov (United States)

Berger, R L

1994-12-01

The hypothermia experiments performed on humans during the Second World War at the German concentration camp in Dachau have been regarded as crimes against humanity, disguised as medical research. For almost 50 years, scientists maintained that the study produced valuable, even if not totally reliable, information. In recent years, the results from the Dachau hypothermia project were glamorized with life-saving potential and a heated ethical dialogue was activated about the use of life-saving but tainted scientific information. In the wake of the debate, an in-depth examination of the scientific rigour of the project was performed and revealed that neither the science nor the scientists from Dachau could be trusted and that the data were worthless. The body of medical opinion accepted the unfavourable determination but a few scientists and ethicists have continued to endorse the validity, of at least parts, of the Dachau hypothermia data. The conduct of the scientific communications about the Dachau hypothermia experiments by the scientific and ethical communities invites serious consideration of a possible ethical misadventure. It appears that for almost 50 years, the results of the study had been endorsed without careful examination of the scientific base of the experiments and that secondary citation of relevant original material may have been commonly employed. These infractions contributed to a myth that good science was practised by the Nazis at Dachau. The more recent emphasis on the life-saving potential of the Dachau data, without citation of credible supporting evidence, has also been misleading. Similarly, acceptance of a determination by an in-depth examination that the 'whole' Dachau project if flawed with simultaneous endorsement of the validity of 'parts' of the results, poses an ethical problem. It is advisable that before seeking ethical consultation about the use of unethically obtained data, scientists should examine the quality of science behind

Collaborative Learning in Problem Solving: A Case Study in Metacognitive Learning

OpenAIRE

Shelly L. Wismath; Doug Orr

2015-01-01

Problem solving and collaborative communication are among the key 21st century skills educators want students to develop. This paper presents results from a study of the collaborative work patterns of 133 participants from a university level course designed to develop transferable problem-solving skills. Most of the class time in this course was spent on actually solving puzzles, with minimal direct instruction; students were allowed to work either independently or in small groups...

No Problem? No Research, Little Learning ... Big Problem!

Directory of Open Access Journals (Sweden)

Fernando Ornelas Marques

2012-06-01

Full Text Available The motivation to carry out this study stemmed from the generalized perception that nowadays youth lacks the skills for the 21st century. Especially the high-level competences like critical thinking, problem solving and autonomy. Several tools can help to improve these competences (e.g. the SCRATCH programming language, but, as researchers and educators, we are mostly concerned with the skill to recognize problems. What if we do not find problems to solve? What if we do not even feel the need to find or solve problems? The problem is to recognize the problem; the next step is to equate the problem; finally we have to feel the need to solve it. No need? No invention. Recognizing a problem is probably the biggest problem of everyday life, because we are permanently faced with problems (many ill-defined problems, which we need to identify, equate and solve.

An improved DPSO with mutation based on similarity algorithm for optimization of transmission lines loading

International Nuclear Information System (INIS)

Shayeghi, H.; Mahdavi, M.; Bagheri, A.

2010-01-01

Static transmission network expansion planning (STNEP) problem acquires a principal role in power system planning and should be evaluated carefully. Up till now, various methods have been presented to solve the STNEP problem. But only in one of them, lines adequacy rate has been considered at the end of planning horizon and the problem has been optimized by discrete particle swarm optimization (DPSO). DPSO is a new population-based intelligence algorithm and exhibits good performance on solution of the large-scale, discrete and non-linear optimization problems like STNEP. However, during the running of the algorithm, the particles become more and more similar, and cluster into the best particle in the swarm, which make the swarm premature convergence around the local solution. In order to overcome these drawbacks and considering lines adequacy rate, in this paper, expansion planning has been implemented by merging lines loading parameter in the STNEP and inserting investment cost into the fitness function constraints using an improved DPSO algorithm. The proposed improved DPSO is a new conception, collectivity, which is based on similarity between the particle and the current global best particle in the swarm that can prevent the premature convergence of DPSO around the local solution. The proposed method has been tested on the Garver's network and a real transmission network in Iran, and compared with the DPSO based method for solution of the TNEP problem. The results show that the proposed improved DPSO based method by preventing the premature convergence is caused that with almost the same expansion costs, the network adequacy is increased considerably. Also, regarding the convergence curves of both methods, it can be seen that precision of the proposed algorithm for the solution of the STNEP problem is more than DPSO approach.

Contentious problems in bioscience and biotechnology: a pilot study of an approach to ethics education.

Science.gov (United States)

Berry, Roberta M; Borenstein, Jason; Butera, Robert J

2013-06-01

This manuscript describes a pilot study in ethics education employing a problem-based learning approach to the study of novel, complex, ethically fraught, unavoidably public, and unavoidably divisive policy problems, called "fractious problems," in bioscience and biotechnology. Diverse graduate and professional students from four US institutions and disciplines spanning science, engineering, humanities, social science, law, and medicine analyzed fractious problems employing "navigational skills" tailored to the distinctive features of these problems. The students presented their results to policymakers, stakeholders, experts, and members of the public. This approach may provide a model for educating future bioscientists and bioengineers so that they can meaningfully contribute to the social understanding and resolution of challenging policy problems generated by their work.

On similarity and scaling of the radiative transfer equation

International Nuclear Information System (INIS)

Mitrescu, C.; Stephens, G.L.

2004-01-01

The present paper shows how the well-known similarity and scaling concepts are properties of the radiative transfer equation and not specifically of the degree of anisotropy of the phase function. It is shown that the key assumption regarding the angular dependence of the radiative field is essential in determining both the value for the parameter used to scale the radiative transfer, as well as the number of streams used in calculating the radiances for various atmospheric problems. Simulations performed on realistic type of cirrus clouds, characterized by strongly anisotropic functions, demonstrates the superior computational advantage for accurately simulating radiances. A new approach for determining the scaling parameter is introduced

Attention Problems in Very Preterm Children from Childhood to Adulthood: The Bavarian Longitudinal Study

Science.gov (United States)

Breeman, Linda D.; Jaekel, Julia; Baumann, Nicole; Bartmann, Peter; Wolke, Dieter

2016-01-01

Background: Very preterm (VP; gestational age attention problems in childhood and adulthood. The stability of these problems into adulthood is not known. Methods: The Bavarian Longitudinal Study is a prospective cohort study that followed 260 VP/VLBW and 229 term-born…

Formal language constrained path problems

Energy Technology Data Exchange (ETDEWEB)

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

1997-07-08

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

Study of Some Technical Problems in Nuclear Emulsions

International Nuclear Information System (INIS)

Tarrega Tornero, M. P.

1967-01-01

A methodological study of various technical aspects of photographic emulsions is presented. This study enables the emulsion method to be used in certain physical problems, and can be summarized under the following headings. 1) Variation of different ionization indices with the degree of development. A measure of the degree of development is introduced. This measure called the α -mark, is based on the average width of tracks due to α-particles. Using the α-mack the influence of several factors such as the duration, temperature and concentration of the developing liquid are investigated. A comparative study of the sensitivity of llford C 2 and K 2 emulsions is given. (Author) 9 refs

Quality of courses evaluated by 'predictions' rather than opinions: Fewer respondents needed for similar results.

Science.gov (United States)

Cohen-Schotanus, Janke; Schönrock-Adema, Johanna; Schmidt, Henk G

2010-01-01

A well-known problem with student surveys is a too low response rate. Experiences with predicting electoral outcomes, which required much smaller sample sizes, inspired us to adopt a similar approach to course evaluation. We expected that having respondents estimate the average opinions of their peers required fewer respondents for comparable outcomes than giving own opinions. Two course evaluation studies were performed among successive first-year medical students (N = 380 and 450, respectively). Study 1: Half the cohort gave opinions on nine questions, while the other half predicted the average outcomes. A prize was offered for the three best predictions (motivational remedy). Study 2: Half the cohort gave opinions, a quarter made predictions without a prize and a quarter made predictions with previous year's results as prior knowledge (cognitive remedy). The numbers of respondents required for stable outcomes were determined following an iterative process. Differences between numbers of respondents required and between average scores were analysed with ANOVA. In both studies, the prediction conditions required significantly fewer respondents (p < 0.001) for comparable outcomes. The informed prediction condition required the fewest respondents (N < 20). Problems with response rates can be reduced by asking respondents to predict evaluation outcomes rather than giving opinions.

Externalizing problems, attention regulation, and household chaos: A longitudinal behavioral genetic study

Science.gov (United States)

Wang, Zhe; Deater-Deckard, Kirby; Petrill, Stephen A.; Thompson, Lee A.

2015-01-01

Previous research has documented a robust link between difficulties in self-regulation and development of externalizing problems (i.e., aggression and delinquency). In the current study, we examined the longitudinal additive and interactive genetic and environmental covariation underlying this well-established link using a twin design. The sample included 131 pairs of monozygotic twins and 173 pairs of same-sex dizygotic twins who participated in three waves of annual assessment. Mothers and fathers provided reports of externalizing problems. Teacher report and observer rating were used to assess twin’s attention regulation. The etiology underlying the link between externalizing problems and attention regulation shifted from a common genetic mechanism to a common environmental mechanism in the transition across middle childhood. Household chaos moderated the genetic variance of and covariance between externalizing problems and attention regulation. The genetic influence on individual differences in both externalizing problems and attention regulation was stronger in more chaotic household. However, higher levels of household chaos attenuated the genetic link between externalizing problems and attention regulation. PMID:22781853

Problem-Oriented Project Studies

DEFF Research Database (Denmark)

Nielsen, Jørgen Lerche; Danielsen, Oluf

2012-01-01

, providing lectures and seminars, giving assignments, and marking papers and essays is complemented and in some ways overruled by a new role as supervisor and facilitator for the group of students working with a research problem that they have picked themselves. However, different dimensions of this new...... teacher role can be observed – from expert in an academic field to a role that focuses more on processes, methodological dimensions, and the importance of a reflexive approach. In some situations, the role as social mediator is needed questioning and assisting the members of the group in the complex task...

Problem-oriented project studies

DEFF Research Database (Denmark)

Nielsen, Jørgen Lerche; Danielsen, Oluf

2010-01-01

and marking papers / essays is complemented and in some way overruled by a new role as supervisor and facilitator for the group of students working with a research problem, they themselves have picked. However different dimensions of this new teacher role can be seen – from expert in an academic field (result......-oriented focusing on how the final product demonstrates the students’ ‘correct’ way to handle the academic aspects of the subject in mind) to a role more focusing on processes, methodological dimensions and stressing the importance of a reflexive approach. Some teachers may even tend to take on a role...

Birds of a feather sit together: physical similarity predicts seating choice.

Science.gov (United States)

Mackinnon, Sean P; Jordan, Christian H; Wilson, Anne E

2011-07-01

Across four studies, people sat (or reported they would sit) closer to physically similar others. Study 1 revealed significant aggregation in seating patterns on two easily observed characteristics: glasses wearing and sex. Study 2 replicated this finding with a wider variety of physical traits: race, sex, glasses wearing, hair length, and hair color. The overall tendency for people to sit beside physically similar others remained significant when controlling for sex and race, suggesting people aggregate on physical dimensions other than broad social categories. Study 3 conceptually replicated these results in a laboratory setting. The more physically similar participants were to a confederate, the closer they sat before an anticipated interaction when controlling for sex, race, and attractiveness similarity. In Study 4, overall physical similarity and glasses wearing similarity predicted self-reported seating distance. These effects were mediated by perceived attitudinal similarity. Liking and inferred acceptance also received support as mediators for glasses wearing similarity. © 2011 by the Society for Personality and Social Psychology, Inc

Prioritization of candidate disease genes by combining topological similarity and semantic similarity.

Science.gov (United States)

Liu, Bin; Jin, Min; Zeng, Pan

2015-10-01

The identification of gene-phenotype relationships is very important for the treatment of human diseases. Studies have shown that genes causing the same or similar phenotypes tend to interact with each other in a protein-protein interaction (PPI) network. Thus, many identification methods based on the PPI network model have achieved good results. However, in the PPI network, some interactions between the proteins encoded by candidate gene and the proteins encoded by known disease genes are very weak. Therefore, some studies have combined the PPI network with other genomic information and reported good predictive performances. However, we believe that the results could be further improved. In this paper, we propose a new method that uses the semantic similarity between the candidate gene and known disease genes to set the initial probability vector of a random walk with a restart algorithm in a human PPI network. The effectiveness of our method was demonstrated by leave-one-out cross-validation, and the experimental results indicated that our method outperformed other methods. Additionally, our method can predict new causative genes of multifactor diseases, including Parkinson's disease, breast cancer and obesity. The top predictions were good and consistent with the findings in the literature, which further illustrates the effectiveness of our method. Copyright © 2015 Elsevier Inc. All rights reserved.

Application of Influence Function Method to the Fretting Wear Problems

Energy Technology Data Exchange (ETDEWEB)

Lee, Choon Yeol; Tian, Li Si; Bae, Joon Woo; Chai, Young Suck [Yeungnam University, Gyongsan (Korea, Republic of)

2006-07-01

Numerical analysis by influence function method (IFM) is demonstrated in this study in order to investigate the fretting wear problems on the secondary side of the steam generator, caused by flow induced vibration. Two-dimensional numerical contact model in terms of Cauchy integral equation is developed. The distributions of normal pressures, shear stresses and displacement fields are derived between two contact bodies which have similar elastic properties. The work rate model is adopted to find the wear amounts between two materials. The results are compared with the solutions by finite element analyses, which show the utilization of the present method to the fretting wear problems.

Application of Influence Function Method to the Fretting Wear Problems

International Nuclear Information System (INIS)

Lee, Choon Yeol; Tian, Li Si; Bae, Joon Woo; Chai, Young Suck

2006-01-01

Numerical analysis by influence function method (IFM) is demonstrated in this study in order to investigate the fretting wear problems on the secondary side of the steam generator, caused by flow induced vibration. Two-dimensional numerical contact model in terms of Cauchy integral equation is developed. The distributions of normal pressures, shear stresses and displacement fields are derived between two contact bodies which have similar elastic properties. The work rate model is adopted to find the wear amounts between two materials. The results are compared with the solutions by finite element analyses, which show the utilization of the present method to the fretting wear problems

Quantum resonance for simulating combinatorial problems

International Nuclear Information System (INIS)

Zak, Michail; Fijany, Amir

2005-01-01

Quantum computing by simulations is based upon similarity between mathematical formalism of a quantum phenomenon and phenomena to be analyzed. In this Letter, the mathematical formalism of quantum resonance combined with tensor product decomposability of unitary evolutions is mapped onto a class of NP-complete combinatorial problems. It has been demonstrated that nature has polynomial resources for solving NP-complete problems and that will help to develop a new strategy for artificial intelligence, as well as to re-evaluate the role of natural selection in biological evolution

Barriers and Facilitators for Health Behavior Change among Adults from Multi-Problem Households: A Qualitative Study

NARCIS (Netherlands)

Nagelhout, Gera; Hogeling, Lette; Spruijt, Renate; Postma, Nathalie; Vries, de Hein

2017-01-01

Multi-problem households are households with problems on more than one of the following core problem areas: socio-economic problems, psycho-social problems, and problems related to child care. The aim of this study was to examine barriers and facilitators for health behavior change among adults from

The Application of the Weighted k-Partite Graph Problem to the Multiple Alignment for Metabolic Pathways.

Science.gov (United States)

Chen, Wenbin; Hendrix, William; Samatova, Nagiza F

2017-12-01

The problem of aligning multiple metabolic pathways is one of very challenging problems in computational biology. A metabolic pathway consists of three types of entities: reactions, compounds, and enzymes. Based on similarities between enzymes, Tohsato et al. gave an algorithm for aligning multiple metabolic pathways. However, the algorithm given by Tohsato et al. neglects the similarities among reactions, compounds, enzymes, and pathway topology. How to design algorithms for the alignment problem of multiple metabolic pathways based on the similarity of reactions, compounds, and enzymes? It is a difficult computational problem. In this article, we propose an algorithm for the problem of aligning multiple metabolic pathways based on the similarities among reactions, compounds, enzymes, and pathway topology. First, we compute a weight between each pair of like entities in different input pathways based on the entities' similarity score and topological structure using Ay et al.'s methods. We then construct a weighted k-partite graph for the reactions, compounds, and enzymes. We extract a mapping between these entities by solving the maximum-weighted k-partite matching problem by applying a novel heuristic algorithm. By analyzing the alignment results of multiple pathways in different organisms, we show that the alignments found by our algorithm correctly identify common subnetworks among multiple pathways.

Non self-similar collapses described by the non-linear Schroedinger equation

International Nuclear Information System (INIS)

Berge, L.; Pesme, D.

1992-01-01

We develop a rapid method in order to find the contraction rates of the radially symmetric collapsing solutions of the nonlinear Schroedinger equation defined for space dimensions exceeding a threshold value. We explicitly determine the asymptotic behaviour of these latter solutions by solving the non stationary linear problem relative to the nonlinear Schroedinger equation. We show that the self-similar states associated with the collapsing solutions are characterized by a spatial extent which is bounded from the top by a cut-off radius

Study of ODE limit problems for reaction-diffusion equations

Directory of Open Access Journals (Sweden)

Jacson Simsen

2018-01-01

Full Text Available In this work we study ODE limit problems for reaction-diffusion equations for large diffusion and we study the sensitivity of nonlinear ODEs with respect to initial conditions and exponent parameters. Moreover, we prove continuity of the flow and weak upper semicontinuity of a family of global attractors for reaction-diffusion equations with spatially variable exponents when the exponents go to 2 in \\(L^{\\infty}(\\Omega\\ and the diffusion coefficients go to infinity.

Correlation between social proximity and mobility similarity.

Science.gov (United States)

Fan, Chao; Liu, Yiding; Huang, Junming; Rong, Zhihai; Zhou, Tao

2017-09-20

Human behaviors exhibit ubiquitous correlations in many aspects, such as individual and collective levels, temporal and spatial dimensions, content, social and geographical layers. With rich Internet data of online behaviors becoming available, it attracts academic interests to explore human mobility similarity from the perspective of social network proximity. Existent analysis shows a strong correlation between online social proximity and offline mobility similarity, namely, mobile records between friends are significantly more similar than between strangers, and those between friends with common neighbors are even more similar. We argue the importance of the number and diversity of common friends, with a counter intuitive finding that the number of common friends has no positive impact on mobility similarity while the diversity plays a key role, disagreeing with previous studies. Our analysis provides a novel view for better understanding the coupling between human online and offline behaviors, and will help model and predict human behaviors based on social proximity.

Analytic Approach to Resolving Parking Problems in Downtown Zagreb

Directory of Open Access Journals (Sweden)

Adolf Malić

2005-01-01

Full Text Available Parking issue is one of the major problems in Zagreb, andin relation to that Zagreb does not differ from other similar orbigger European cities. The problem the city is facing is beingpresented in the paper. It is complex and can be solved gradually,using operative and planning measures, by applying influentialparameters assessments based on which the appropriateparking-garage spaces assessment would be selected. Besides,all the knowledge learned from experiences of similar Europeancities should be used in resolving stationary traffic problem.Introduction of fast public urban transport would providepassengers with improved services (particularly in relation tothe travelling time introducing modern traffic system thatwould reduce the travelling time to below 30 minutes for the farthestrelations. Further improvement in reducing parking problemsin downtown as well as Zagreb broader area would not bepossible without t,nplementing th.s approach.

[Adolescents and new technologies: Behaviours pointing a possible addiction problem].