WorldWideScience

Sample records for understand multiple representations

  1. Multiple Representations and the Understanding of Taylor Polynomials

    Science.gov (United States)

    Habre, Samer

    2009-01-01

    The study of Maclaurin and Taylor polynomials entails the comprehension of various new mathematical ideas. Those polynomials are initially discussed at the college level in a calculus class and then again in a course on numerical methods. This article investigates the understanding of these polynomials by students taking a numerical methods class…

  2. Differentiating for Multiple Intelligences: A Study of Students' Understandings through the Use of Aesthetic Representations

    Science.gov (United States)

    Crim, Courtney L.; Kennedy, Kimberley D.; Thornton, Jenifer S.

    2013-01-01

    This article reviews the relevant literature in regard to differentiation, multiple intelligences, and aesthetic representations. Next, it presents the methodology, reports findings, and discusses themes related to the authors' research questions. Finally, it concludes that tapping into students' multiple intelligence strength(s) is an excellent…

  3. Pre-Service Teachers' Understanding of Fraction Multiplication, Representational Knowledge, and Computational Skills

    Science.gov (United States)

    Son, Ji-Won; Lee, Ji-Eun

    2016-01-01

    Despite the importance of teacher fractional knowledge, there are several areas of teacher understanding that are not well understood. The purpose of this study was to characterise profiles of pre-service teachers' (PSTs) mathematical competence on the topic of fraction multiplication by examining PSTs' understanding of multiplication of fractions…

  4. Multiple visions of Indonesia's mud volcano: understanding representations of disaster across discursive settings.

    Science.gov (United States)

    Drake, Phillip

    2016-04-01

    The Lapindo mudflow is one of the most controversial disasters in Indonesian history. Despite its unique biophysical features, most consider the mudflow a social disaster as scientific conflicts about its main trigger have evolved into legal disputes over accountability and rights. This paper examines this 'trigger debate', the stakes of scientific contention and the broader social and natural dynamics that shape the terms of this debate. A Latourian impulse drives this analysis, which aims to improve both understandings of--and responses to--complex disasters. This paper also notes that the stakes of representation extend to constructions of its stakeholders, especially to victims. As socionatural disasters become an increasingly common feature of the contemporary world, from mud volcanoes to extreme weather events caused by global warming, it is more important than ever to understand the dynamics of representing disasters and stakeholders. © 2016 The Author(s). Disasters © Overseas Development Institute, 2016.

  5. The Role of Multiple Representations in the Understanding of Ideal Gas Problems

    Science.gov (United States)

    Madden, Sean P.; Jones, Loretta L.; Rahm, Jrene

    2011-01-01

    This study examined the representational competence of students as they solved problems dealing with the temperature-pressure relationship for ideal gases. Seven students enrolled in a first-semester general chemistry course and two advanced undergraduate science majors participated in the study. The written work and transcripts from videotaped…

  6. Multiple Sparse Representations Classification

    Science.gov (United States)

    Plenge, Esben; Klein, Stefan S.; Niessen, Wiro J.; Meijering, Erik

    2015-01-01

    Sparse representations classification (SRC) is a powerful technique for pixelwise classification of images and it is increasingly being used for a wide variety of image analysis tasks. The method uses sparse representation and learned redundant dictionaries to classify image pixels. In this empirical study we propose to further leverage the redundancy of the learned dictionaries to achieve a more accurate classifier. In conventional SRC, each image pixel is associated with a small patch surrounding it. Using these patches, a dictionary is trained for each class in a supervised fashion. Commonly, redundant/overcomplete dictionaries are trained and image patches are sparsely represented by a linear combination of only a few of the dictionary elements. Given a set of trained dictionaries, a new patch is sparse coded using each of them, and subsequently assigned to the class whose dictionary yields the minimum residual energy. We propose a generalization of this scheme. The method, which we call multiple sparse representations classification (mSRC), is based on the observation that an overcomplete, class specific dictionary is capable of generating multiple accurate and independent estimates of a patch belonging to the class. So instead of finding a single sparse representation of a patch for each dictionary, we find multiple, and the corresponding residual energies provides an enhanced statistic which is used to improve classification. We demonstrate the efficacy of mSRC for three example applications: pixelwise classification of texture images, lumen segmentation in carotid artery magnetic resonance imaging (MRI), and bifurcation point detection in carotid artery MRI. We compare our method with conventional SRC, K-nearest neighbor, and support vector machine classifiers. The results show that mSRC outperforms SRC and the other reference methods. In addition, we present an extensive evaluation of the effect of the main mSRC parameters: patch size, dictionary size, and

  7. Multiple Representations of Buoyancy

    Science.gov (United States)

    Oliviera, Jessica; Weglarz, Meredith; Vesenka, James

    2009-10-01

    For many students the concept of buoyancy falls under a category that can be loosely described as ``knowing it when they see it.'' Unfortunately some of the misconceptions this generates are that ``objects float because they are light'' and ``objects float because they are full of air'' [1]. Those these can some times be true, these descriptions are vague at best, and frequently can be wrong. Part of these misconceptions may stem from incomplete immersion of the object in the fluid and the vector nature of forces. We describe a demonstration/lab activity to help students make sense about relationship between the tension on and weight of an object immersed in water. The activity is in rich in multiple representations, graphical, diagrammatical as well as mathematical. A simple four question multiple choice pre/post test survey has been developed to evaluate the effectiveness of the lab activity.[4pt] [1] Bruce Harlan ``Diving Science'', www.stmatthewsschool.com/deep/pdfs/Diving%20Science.pdf

  8. Multiple representations in physics education

    CERN Document Server

    Duit, Reinders; Fischer, Hans E

    2017-01-01

    This volume is important because despite various external representations, such as analogies, metaphors, and visualizations being commonly used by physics teachers, educators and researchers, the notion of using the pedagogical functions of multiple representations to support teaching and learning is still a gap in physics education. The research presented in the three sections of the book is introduced by descriptions of various psychological theories that are applied in different ways for designing physics teaching and learning in classroom settings. The following chapters of the book illustrate teaching and learning with respect to applying specific physics multiple representations in different levels of the education system and in different physics topics using analogies and models, different modes, and in reasoning and representational competence. When multiple representations are used in physics for teaching, the expectation is that they should be successful. To ensure this is the case, the implementati...

  9. Cognitive Dissonance as an Instructional Tool for Understanding Chemical Representations

    Science.gov (United States)

    Corradi, David; Clarebout, Geraldine; Elen, Jan

    2015-01-01

    Previous research on multiple external representations (MER) indicates that sequencing representations (compared with presenting them as a whole) can, in some cases, increase conceptual understanding if there is interference between internal and external representations. We tested this mechanism by sequencing different combinations of scientific…

  10. Asymmetric translation between multiple representations in chemistry

    Science.gov (United States)

    Lin, Yulan I.; Son, Ji Y.; Rudd, James A., II

    2016-03-01

    Experts are more proficient in manipulating and translating between multiple representations (MRs) of a given concept than novices. Studies have shown that instruction using MR can increase student understanding of MR, and one model for MR instruction in chemistry is the chemistry triplet proposed by Johnstone. Concreteness fading theory suggests that presenting concrete representations before abstract representations can increase the effectiveness of MR instruction; however, little work has been conducted on varying the order of different representations during instruction and the role of concreteness in assessment. In this study, we investigated the application of concreteness fading to MR instruction and assessment in teaching chemistry. In two experiments, undergraduate students in either introductory psychology courses or general chemistry courses were given MR instruction on phase changes using different orders of presentation and MR assessment questions based on the representations in the chemistry triplet. Our findings indicate that the order of presentation based on levels of concreteness in MR chemistry instruction is less important than implementation of comprehensive MR assessments. Even after MR instruction, students display an asymmetric understanding of the chemical phenomenon on the MR assessments. Greater emphasis on MR assessments may be an important component in MR instruction that effectively moves novices toward more expert MR understanding.

  11. Generating Cognitive Dissonance in Student Interviews through Multiple Representations

    Science.gov (United States)

    Linenberger, Kimberly J.; Bretz, Stacey Lowery

    2012-01-01

    This study explores what students understand about enzyme-substrate interactions, using multiple representations of the phenomenon. In this paper we describe our use of the 3 Phase-Single Interview Technique with multiple representations to generate cognitive dissonance within students in order to uncover misconceptions of enzyme-substrate…

  12. Multiple Interactive Representations for Fractions Learning

    NARCIS (Netherlands)

    Feenstra, Laurens; Aleven, Vincent; Rummel, Nikol; Taatgen, Niels; Aleven,; Kay, J; Mostow, J

    2010-01-01

    Multiple External Representations (MERs) have been used successfully in instructional activities, including fractions However, students often have difficulties making the connections between the MERs spontaneously We argue that interactive fraction representations may help students in discovering

  13. Understanding as Integration of Heterogeneous Representations

    Science.gov (United States)

    Martínez, Sergio F.

    2014-03-01

    The search for understanding is a major aim of science. Traditionally, understanding has been undervalued in the philosophy of science because of its psychological underpinnings; nowadays, however, it is widely recognized that epistemology cannot be divorced from psychology as sharp as traditional epistemology required. This eliminates the main obstacle to give scientific understanding due attention in philosophy of science. My aim in this paper is to describe an account of scientific understanding as an emergent feature of our mastering of different (causal) explanatory frameworks that takes place through the mastering of scientific practices. Different practices lead to different kinds of representations. Such representations are often heterogeneous. The integration of such representations constitute understanding.

  14. Representational Classroom Practices that Contribute to Students' Conceptual and Representational Understanding of Chemical Bonding

    Science.gov (United States)

    Hilton, Annette; Nichols, Kim

    2011-11-01

    Understanding bonding is fundamental to success in chemistry. A number of alternative conceptions related to chemical bonding have been reported in the literature. Research suggests that many alternative conceptions held by chemistry students result from previous teaching; if teachers are explicit in the use of representations and explain their content-specific forms and functions, this might be avoided. The development of an understanding of and ability to use multiple representations is crucial to students' understanding of chemical bonding. This paper draws on data from a larger study involving two Year 11 chemistry classes (n = 27, n = 22). It explores the contribution of explicit instruction about multiple representations to students' understanding and representation of chemical bonding. The instructional strategies were documented using audio-recordings and the teacher-researcher's reflection journal. Pre-test-post-test comparisons showed an improvement in conceptual understanding and representational competence. Analysis of the students' texts provided further evidence of the students' ability to use multiple representations to explain macroscopic phenomena on the molecular level. The findings suggest that explicit instruction about representational form and function contributes to the enhancement of representational competence and conceptual understanding of bonding in chemistry. However, the scaffolding strategies employed by the teacher play an important role in the learning process. This research has implications for professional development enhancing teachers' approaches to these aspects of instruction around chemical bonding.

  15. Image understanding using sparse representations

    CERN Document Server

    Thiagarajan, Jayaraman J; Turaga, Pavan; Spanias, Andreas

    2014-01-01

    Image understanding has been playing an increasingly crucial role in several inverse problems and computer vision. Sparse models form an important component in image understanding, since they emulate the activity of neural receptors in the primary visual cortex of the human brain. Sparse methods have been utilized in several learning problems because of their ability to provide parsimonious, interpretable, and efficient models. Exploiting the sparsity of natural signals has led to advances in several application areas including image compression, denoising, inpainting, compressed sensing, blin

  16. Understanding leader representations: Beyond implicit leadership theory

    OpenAIRE

    Knee, Robert Everett

    2006-01-01

    The purpose of the present study was to establish evidence for the suggested integration of the theories of connectionism and leadership. Recent theoretical writings in the field of leadership have suggested that the dynamic representations generated by the connectionist perspective is an appropriate approach to understanding how we perceive leaders. Similarly, implicit leadership theory (ILT) explains that our cognitive understandings of leaders are based on a cognitive structure that we u...

  17. The error of representation: basic understanding

    Directory of Open Access Journals (Sweden)

    Daniel Hodyss

    2015-01-01

    Full Text Available Representation error arises from the inability of the forecast model to accurately simulate the climatology of the truth. We present a rigorous framework for understanding this kind of error of representation. This framework shows that the lack of an inverse in the relationship between the true climatology (true attractor and the forecast climatology (forecast attractor leads to the error of representation. A new gain matrix for the data assimilation problem is derived that illustrates the proper approaches one may take to perform Bayesian data assimilation when the observations are of states on one attractor but the forecast model resides on another. This new data assimilation algorithm is the optimal scheme for the situation where the distributions on the true attractor and the forecast attractors are separately Gaussian, and there exists a linear map between them. The results of this theory are illustrated in a simple Gaussian multivariate model.

  18. Understanding Tourism Development: A Representational Approach

    OpenAIRE

    Meliou, Elina; Maroudas, Leonidas

    2009-01-01

    The article investigates hotel employees and postgraduate students’ representations of “tourism development”, using social representations theory. Data from a sample of eighty participants were collected on Chios Island, Greece. To reveal social representations a word association procedure was applied followed by a correspondence analysis. The analysis attempts to map the meanings associated with “tourism development” and to pinpoint the links between those meanings. Results highlight differe...

  19. Multiple External Representations: Bridges or Barriers to Climate Literacy?

    Science.gov (United States)

    Holzer, M. A.

    2012-12-01

    The continuous barrage of science related headlines and other media sources warn us of the need to heed the imperative for a science literate society. Climate change, genetics, evolution are a few of the charged and complex scientific topics requiring public understanding of the science to fully grasp the enormous reach of these topics in our daily lives. For instance, our global climate is changing as evidenced by the analysis of Earth observing satellite data, in-situ data, and proxy data records. How we as a global society decide to address the needs associated with a changing climate are contingent upon having a population that understands how the climate system functions, and can therefore make informed decisions on how to mitigate the effects of climate change. Communication in science relies heavily on the use of multiple representations to support the claims presented. However, these multiple representations require spatial and temporal skills to interpret information portrayed in them, and how a person engages with complex text and the multiple representations varies with the level of expertise one has with the content area. For example, a climatologist will likely identify anomalous data more quickly than a novice when presented with a graph of temperature change over time. These representations are used throughout textbooks as well as popular reading materials such as newspapers and magazines without much consideration for how a reader engages with complex text, diagrams, images, and graphs. If the ability to read and interact with scientific text found in popular literature is perceived as a worthy goal of scientific literacy, then it is imperative that readers understand the relationship between multiple representations and the text while interacting with the science literature they are reading. For example, in climate related articles multiple representations not only support the content, but they are part of the content not to be overlooked by a

  20. Understanding Linear Functions and Their Representations

    Science.gov (United States)

    Wells, Pamela J.

    2015-01-01

    Linear functions are an important part of the middle school mathematics curriculum. Students in the middle grades gain fluency by working with linear functions in a variety of representations (NCTM 2001). Presented in this article is an activity that was used with five eighth-grade classes at three different schools. The activity contains 15 cards…

  1. Cross-cultural understanding through visual representation

    Directory of Open Access Journals (Sweden)

    Kristina Beckman

    2011-04-01

    Full Text Available This article analyzes international students’ drawings of their home countries’ essay assignments. These English as a Second Language (ESL students often have difficulty in meeting the local demands of our Writing Program, which centers on argumentative writing with thesis and support. Any part of an essay deemed irrelevant is censured as “off topic;” some students see this structure as too direct or even impolite. While not all students found visual representation easy, the drawings reveal some basic assumptions about writing embodied in their native cultures’ assignments. We discuss the drawings first for visual rhetorical content, then in the students’ own terms. Last, we consider how our own pedagogy has been shaped.

  2. The role of physical digit representation and numerical magnitude representation in children's multiplication fact retrieval.

    Science.gov (United States)

    De Visscher, Alice; Noël, Marie-Pascale; De Smedt, Bert

    2016-12-01

    Arithmetic facts, in particular multiplication tables, are thought to be stored in long-term memory and to be interference prone. At least two representations underpinning these arithmetic facts have been suggested: a physical representation of the digits and a numerical magnitude representation. We hypothesized that both representations are possible sources of interference that could explain individual differences in multiplication fact performance and/or in strategy use. We investigated the specificity of these interferences on arithmetic fact retrieval and explored the relation between interference and performance on the different arithmetic operations and on general mathematics achievement. Participants were 79 fourth-grade children (M age =9.6 years) who completed a products comparison and a multiplication production task with verbal strategy reports. Performances on a speeded calculation test including the four operations and on a general mathematics achievement test were also collected. Only the interference coming from physical representations was a significant predictor of the performance across multiplications. However, both the magnitude and physical representations were unique predictors of individual differences in multiplication. The frequency of the retrieval strategy across multiplication problems and across individuals was determined only by the physical representation, which therefore is suggested as being responsible for memory storage issues. Interestingly, this impact of physical representation was not observed when predicting performance on subtraction or on general mathematical achievement. In contrast, the impact of the numerical magnitude representation was more general in that it was observed across all arithmetic operations and in general mathematics achievement. Copyright © 2016 Elsevier Inc. All rights reserved.

  3. Teaching and Evaluation Materials Utilizing Multiple Representations in Mechanics

    Science.gov (United States)

    Savinainen, A.; Nieminen, P.; Makynen, A.; Viiri, J.

    2013-01-01

    In this paper, we present materials and teaching ideas utilizing multiple representations in the contexts of kinematics and the force concept. These ideas and materials are substantiated by evidence and can be readily used in teaching with no special training. In addition, we briefly discuss two multiple-choice tests based on physics education…

  4. Graphical representations of data improve student understanding of measurement and uncertainty: An eye-tracking study

    Science.gov (United States)

    Susac, Ana; Bubic, Andreja; Martinjak, Petra; Planinic, Maja; Palmovic, Marijan

    2017-12-01

    Developing a better understanding of the measurement process and measurement uncertainty is one of the main goals of university physics laboratory courses. This study investigated the influence of graphical representation of data on student understanding and interpreting of measurement results. A sample of 101 undergraduate students (48 first year students and 53 third and fifth year students) from the Department of Physics, University of Zagreb were tested with a paper-and-pencil test consisting of eight multiple-choice test items about measurement uncertainties. One version of the test items included graphical representations of the measurement data. About half of the students solved that version of the test while the remaining students solved the same test without graphical representations. The results have shown that the students who had the graphical representation of data scored higher than their colleagues without graphical representation. In the second part of the study, measurements of eye movements were carried out on a sample of thirty undergraduate students from the Department of Physics, University of Zagreb while students were solving the same test on a computer screen. The results revealed that students who had the graphical representation of data spent considerably less time viewing the numerical data than the other group of students. These results indicate that graphical representation may be beneficial for data processing and data comparison. Graphical representation helps with visualization of data and therefore reduces the cognitive load on students while performing measurement data analysis, so students should be encouraged to use it.

  5. Irreducible decomposition and calculating of multiplicity of the symmetric and exterior powers representation of finite groups

    OpenAIRE

    Tamura, Tomoyuki

    2014-01-01

    In this paper we consider symmetric powers representation and exterior powers representation of finite groups, which generated by the representation which has finite dimension over the complex field. We calculate the multiplicity of irreducible component of two representations of some representation by using a character theory of representation and a pre-lambda-ring, for example, the regular representation.

  6. High School Students' Representations and Understandings of Electric Fields

    Science.gov (United States)

    Cao, Ying; Brizuela, Bárbara M.

    2016-01-01

    This study investigates the representations and understandings of electric fields expressed by Chinese high school students 15 to 16 years old who have not received high school level physics instruction. The physics education research literature has reported students' conceptions of electric fields post-instruction as indicated by students'…

  7. The current practice of using multiple representations in year 4 science classrooms

    Science.gov (United States)

    Chuenmanee, Chanoknat; Thathong, Kongsak

    2018-01-01

    Multiple representations have been widely used as a reasoning tool for understanding complex scientific concepts. Thus this study attempted to investigate the current practice of using multiple representations on Year 4 science classrooms in terms of modes and levels which appear in curriculum documents, teaching plans, tasks and assessments, teaching practices, and students' behaviors. Indeed, documentary analysis, classroom observation, and interview were used as the data collection methods. First of all, Year 4 science documents were analyzed. Then classroom observation was used as a collecting method to seek what actually happen in the classroom. Finally, in-depth interviews were used to gather more information and obtain meaningful data. The finding reveals that many modes of verbal, visual, and tactile representations within three levels of representations are posed in Year 4 documents. Moreover, according to classroom observations and interviews, there are three main points of applying multiple representations into classrooms. First of all, various modes of representations were used, however, a huge number of them did not come together with the levels. The levels of representations, secondly, macroscopic and cellular levels were introduced into all classrooms while symbolic level was provided only in some classrooms. Finally, the connection of modes and levels pointed out that modes of representations were used without the considerations on the levels of them. So, it seems to be that teaching practice did not meet the aims of curriculum. Therefore, these issues were being considered in order to organize and design the further science lessons.

  8. Emerging and developing multiplicative structure in students’ visuospatial representations: Four key configuration types

    OpenAIRE

    Finesilver, Carla

    2017-01-01

    Visuospatial representations of quantities and their relations are widely used to support the understanding of basic arithmetic, including multiplicative relationships. These include drawn imagery and concrete manipulatives. This paper defines four particular configurations of nonstandard representation according to the spatial organization of their visual elements. These are: unit containers, unit arrays, array-container blends, and number containers, all of which have been observed to suppo...

  9. Learning Combinations of Multiple Feature Representations for Music Emotion Prediction

    DEFF Research Database (Denmark)

    Madsen, Jens; Jensen, Bjørn Sand; Larsen, Jan

    2015-01-01

    Music consists of several structures and patterns evolving through time which greatly influences the human decoding of higher-level cognitive aspects of music like the emotions expressed in music. For tasks, such as genre, tag and emotion recognition, these structures have often been identified...... and used as individual and non-temporal features and representations. In this work, we address the hypothesis whether using multiple temporal and non-temporal representations of different features is beneficial for modeling music structure with the aim to predict the emotions expressed in music. We test...... this hypothesis by representing temporal and non-temporal structures using generative models of multiple audio features. The representations are used in a discriminative setting via the Product Probability Kernel and the Gaussian Process model enabling Multiple Kernel Learning, finding optimized combinations...

  10. Force Concept Inventory-based multiple-choice test for investigating students’ representational consistency

    Directory of Open Access Journals (Sweden)

    Pasi Nieminen

    2010-08-01

    Full Text Available This study investigates students’ ability to interpret multiple representations consistently (i.e., representational consistency in the context of the force concept. For this purpose we developed the Representational Variant of the Force Concept Inventory (R-FCI, which makes use of nine items from the 1995 version of the Force Concept Inventory (FCI. These original FCI items were redesigned using various representations (such as motion map, vectorial and graphical, yielding 27 multiple-choice items concerning four central concepts underpinning the force concept: Newton’s first, second, and third laws, and gravitation. We provide some evidence for the validity and reliability of the R-FCI; this analysis is limited to the student population of one Finnish high school. The students took the R-FCI at the beginning and at the end of their first high school physics course. We found that students’ (n=168 representational consistency (whether scientifically correct or not varied considerably depending on the concept. On average, representational consistency and scientifically correct understanding increased during the instruction, although in the post-test only a few students performed consistently both in terms of representations and scientifically correct understanding. We also compared students’ (n=87 results of the R-FCI and the FCI, and found that they correlated quite well.

  11. Analysis of the dynamics of reasoning using multiple representations

    NARCIS (Netherlands)

    Jonker, C.M.; Treur, J.

    2002-01-01

    This paper presents a formalisation and analysis method for the dynamics of a reasoning process in which multiple representations play a role. Dynamics of reasoning processes are described by reasoning traces consisting of sequences of reasoning states over time. Reasoning states have a

  12. Coordinating Multiple Representations in a Reform Calculus Textbook

    Science.gov (United States)

    Chang, Briana L.; Cromley, Jennifer G.; Tran, Nhi

    2016-01-01

    Coordination of multiple representations (CMR) is widely recognized as a critical skill in mathematics and is frequently demanded in reform calculus textbooks. However, little is known about the prevalence of coordination tasks in such textbooks. We coded 707 instances of CMR in a widely used reform calculus textbook and analyzed the distributions…

  13. Wait-Time and Multiple Representation Levels in Chemistry Lessons

    Science.gov (United States)

    Li, Winnie Sim Siew; Arshad, Mohammad Yusof

    2014-01-01

    Wait-time is an important aspect in a teaching and learning process, especially after the teacher has posed questions to students, as it is one of the factors in determining quality of students' responses. This article describes the practices of wait-time one after teacher's questions at multiple representation levels among twenty three chemistry…

  14. "Understanding Adam" multiple reciprocal translocations: complex case presentation.

    Science.gov (United States)

    Linder, Carie E; Lu, Xianglan; Kim, Young Mi; Li, Shibo; Pineda, Jose

    2009-01-01

    This article presents a case review of a newborn diagnosed with a complex chromosomal rearrangement, as demonstrated through a painted chromosomal analysis. This infant presented with multiple dysmorphology including cutis aplasia, multiple ocular malformations, bilateral cleft lip and palate, and postnatal hydrocephaly. A chromosomal analysis revealed multiple-ways, balanced translocation involving chromosomes 3, 4, 6, 8, and 9. This case study provides a unique opportunity to, in retrospect, trace each malformation exploring the pathophysiology, etiology, and correlating origin with chromosomal variation. Careful review of this case, enhanced by the visually augmented representation of each translocation, will increase understanding of chromosomal anomalies and their implications in embryological development and clinical presentation.

  15. Students' Learning Strategies with Multiple Representations: Explanations of the Human Breathing Mechanism

    Science.gov (United States)

    Won, Mihye; Yoon, Heojeong; Treagust, David F.

    2014-01-01

    The purpose of this study was to understand how students utilized multiple representations to learn and explain science concepts, in this case the human breathing mechanism. The study was conducted with Grade 11 students in a human biology class. Semistructured interviews and a two-tier diagnostic test were administered to evaluate students'…

  16. Facilitating High School Students' Use of Multiple Representations to Describe and Explain Simple Chemical Reactions

    Science.gov (United States)

    Chandrasegaran, A. L.; Treagust, David F.; Mocerino, Mauro

    2011-01-01

    This study involved the evaluation of the efficacy of a planned instructional program to facilitate understanding of the macroscopic, submicroscopic and symbolic representational systems when describing and explaining chemical reactions by sixty-five Grade 9 students in a Singapore secondary school. A two-tier multiple-choice diagnostic instrument…

  17. Learning Combinations of Multiple Feature Representations for Music Emotion Prediction

    DEFF Research Database (Denmark)

    Madsen, Jens; Jensen, Bjørn Sand; Larsen, Jan

    2015-01-01

    Music consists of several structures and patterns evolving through time which greatly influences the human decoding of higher-level cognitive aspects of music like the emotions expressed in music. For tasks, such as genre, tag and emotion recognition, these structures have often been identified...... and used as individual and non-temporal features and representations. In this work, we address the hypothesis whether using multiple temporal and non-temporal representations of different features is beneficial for modeling music structure with the aim to predict the emotions expressed in music. We test...

  18. Assessing Elementary Understanding of Multiplication Concepts

    Science.gov (United States)

    Smith, Stephanie Z.; Smith, Marvin E.

    2006-01-01

    This article summarizes the basic concepts of multiplication and provides some evidence that the traditional third-grade curriculum and instruction emphasizing memorization of multiplication facts produces much less understanding of the basic concepts of multiplication than a standards-based curriculum and instruction emphasizing construction of…

  19. The representation of multiplication and division facts in memory.

    Science.gov (United States)

    De Brauwer, Jolien; Fias, Wim

    2011-01-01

    Recently, using a training paradigm, Campbell and Agnew (2009) observed cross-operation response time savings with nonidentical elements (e.g., practice 3 + 2, test 5 - 2) for addition and subtraction, showing that a single memory representation underlies addition and subtraction performance. Evidence for cross-operation savings between multiplication and division have been described frequently (e.g., Campbell, Fuchs-Lacelle, & Phenix, 2006) but they have always been attributed to a mediation strategy (reformulating a division problem as a multiplication problem, e.g., Campbell et al., 2006). Campbell and Agnew (2009) therefore concluded that there exists a fundamental difference between addition and subtraction on the one hand and multiplication and division on the other hand. However, our results suggest that retrieval savings between inverse multiplication and division problems can be observed. Even for small problems (solved by direct retrieval) practicing a division problem facilitated the corresponding multiplication problem and vice versa. These findings indicate that shared memory representations underlie multiplication and division retrieval. Hence, memory and learning processes do not seem to differ fundamentally between addition-subtraction and multiplication-division.

  20. Pedagogical Affordances of Multiple External Representations in Scientific Processes

    Science.gov (United States)

    Wu, Hsin-Kai; Puntambekar, Sadhana

    2012-12-01

    Multiple external representations (MERs) have been widely used in science teaching and learning. Theories such as dual coding theory and cognitive flexibility theory have been developed to explain why the use of MERs is beneficial to learning, but they do not provide much information on pedagogical issues such as how and in what conditions MERs could be introduced and used to support students' engagement in scientific processes and develop competent scientific practices (e.g., asking questions, planning investigations, and analyzing data). Additionally, little is understood about complex interactions among scientific processes and affordances of MERs. Therefore, this article focuses on pedagogical affordances of MERs in learning environments that engage students in various scientific processes. By reviewing literature in science education and cognitive psychology and integrating multiple perspectives, this article aims at exploring (1) how MERs can be integrated with science processes due to their different affordances, and (2) how student learning with MERs can be scaffolded, especially in a classroom situation. We argue that pairing representations and scientific processes in a principled way based on the affordances of the representations and the goals of the activities is a powerful way to use MERs in science education. Finally, we outline types of scaffolding that could help effective use of MERs including dynamic linking, model progression, support in instructional materials, teacher support, and active engagement.

  1. Mathematical Representation by Students in Building Relational Understanding on Concepts of Area and Perimeter of Rectangle

    Science.gov (United States)

    Anwar, Rahmad Bustanul; Yuwono, Ipung; As'ari, Abdur Rahman; Sisworo; Dwi, Rahmawati

    2016-01-01

    Representation is an important aspect of learners in building a relational understanding of mathematical concepts. But the ability of a mathematical representation of students in building relational understanding is still very limited. The purpose of this research is to description of mathematical representation of students who appear in building…

  2. Recent advances in understanding multiple myeloma.

    Science.gov (United States)

    Dhakal, Binod; Girnius, Saulius; Hari, Parameswaran

    2016-01-01

    There have been major recent advancements in the understanding and management of multiple myeloma. Diagnostic criteria have been revised and former ultra-high-risk smoldering multiple myeloma is now considered multiple myeloma in need of treatment. Understanding clonal progression, evolution, and tides not only has helped elucidate the disease behavior but might help expand therapeutic choices in order to select appropriate treatment for patients. Unprecedented response rates with modern triplet induction therapies containing proteasome inhibitor and immunomodulators have made this approach standard for initial treatment. The US Food and Drug Administration approved four new drugs (two targeted antibodies and two oral agents) in 2015 in relapsed/refractory multiple myeloma and these drugs along with the other already-available drugs have now increased the choices of regimens. Even drugs without single-agent activity, such as panobinostat and elotuzumab, have an important role, especially in the proteasome inhibitor refractory setting. Recent studies done in the context of novel agent induction suggest that high-dose therapy followed by autologous transplant continues to improve response rates and progression-free survival, thus underscoring their role in transplant-eligible patients. Evolving paradigms in the treatment of multiple myeloma include newer promising immune approaches, such as adoptive cellular therapies, vaccines, or antibody-based immune manipulations. Though multiple myeloma is still considered incurable, it is clear that with the improved understanding of disease biology and clonal architecture of relapse combined with the availability of multi-targeted approaches, we are ever closer to a lasting cure or transformation into indolent and long-lasting disease courses or both.

  3. Patterns of multiple representation use by experts and novices during physics problem solving

    Directory of Open Access Journals (Sweden)

    Patrick B. Kohl

    2008-06-01

    Full Text Available It is generally believed that students should use multiple representations in solving certain physics problems, and earlier work in PER has begun to outline how experts and novices differ in their use of multiple representations. In this study, we build on this foundation by interviewing expert and novice physicists as they solve two types of multiple representation problems: those in which multiple representations are provided for them and those in which the students must construct their own representations. We analyze in detail the types of representations subjects use and the order and manner in which they are used. Expert and novice representation use is surprisingly similar in some ways, especially in that both experts and novices make significant use of multiple representations. Some significant differences also emerge. Experts are more flexible in terms of starting point and move between the available representations more quickly, and novices tend to move between more representations in total. In addition, we find that an examination of how often and when multiple representations are used is inadequate to fully characterize a problem-solving episode; one must also consider the purpose behind the use of the available representations. This analysis of how experts and novices use representations sharpens the differences between the two groups, demonstrates analysis techniques that may be useful in future work, and suggests possible paths for instruction.

  4. Using Instruments to Understand Argument Structure: Evidence for Gradient Representation

    Science.gov (United States)

    Rissman, Lilia; Rawlins, Kyle; Landau, Barbara

    2015-01-01

    The arguments of a verb are commonly assumed to correspond to the event participants specified by the verb. That is, drink has two arguments because drink specifies two participants: someone who drinks and something that gets drunk. This correspondence does not appear to hold, however, in the case of instrumental participants, e.g. John drank the soda with a straw. Verbs such as slice and write have been argued to specify an instrumental participant, even though instruments do not pattern like arguments given other criteria. In this paper, we investigated how instrumental verbs are represented, testing the hypothesis that verbs such as slice encode three participants in the same way that dative verbs such as lend encode three participants. In two experiments English-speakers reported their judgments about the number of participants specified by a verb, e.g. that drink specifies two participants. These judgments indicate that slice does not encode three distinct arguments. Nonetheless, some verbs were systematically more likely to elicit the judgment that the instrument is specified by the verb, a pattern that held across individual subjects. To account for these findings, we propose that instruments are not independent verbal arguments but are represented in a gradient away: an instrument may be a more or less salient part of the force exerted by an agent. These results inform our understanding of the relationship between argument structure and event representation, raising questions concerning the role of arguments in language processing and learning. PMID:26057832

  5. Multiple instance learning tracking method with local sparse representation

    KAUST Repository

    Xie, Chengjun

    2013-10-01

    When objects undergo large pose change, illumination variation or partial occlusion, most existed visual tracking algorithms tend to drift away from targets and even fail in tracking them. To address this issue, in this study, the authors propose an online algorithm by combining multiple instance learning (MIL) and local sparse representation for tracking an object in a video system. The key idea in our method is to model the appearance of an object by local sparse codes that can be formed as training data for the MIL framework. First, local image patches of a target object are represented as sparse codes with an overcomplete dictionary, where the adaptive representation can be helpful in overcoming partial occlusion in object tracking. Then MIL learns the sparse codes by a classifier to discriminate the target from the background. Finally, results from the trained classifier are input into a particle filter framework to sequentially estimate the target state over time in visual tracking. In addition, to decrease the visual drift because of the accumulative errors when updating the dictionary and classifier, a two-step object tracking method combining a static MIL classifier with a dynamical MIL classifier is proposed. Experiments on some publicly available benchmarks of video sequences show that our proposed tracker is more robust and effective than others. © The Institution of Engineering and Technology 2013.

  6. The role of visual representations in college students' understanding of mathematical notation.

    Science.gov (United States)

    Atagi, Natsuki; DeWolf, Melissa; Stigler, James W; Johnson, Scott P

    2016-09-01

    Developing understanding of fractions involves connections between nonsymbolic visual representations and symbolic representations. Initially, teachers introduce fraction concepts with visual representations before moving to symbolic representations. Once the focus is shifted to symbolic representations, the connections between visual representations and symbolic notation are considered to be less useful, and students are rarely asked to connect symbolic notation back to visual representations. In 2 experiments, we ask whether visual representations affect understanding of symbolic notation for adults who understand symbolic notation. In a conceptual fraction comparison task (e.g., Which is larger, 5 / a or 8 / a? ), participants were given comparisons paired with accurate, helpful visual representations, misleading visual representations, or no visual representations. The results show that even college students perform significantly better when accurate visuals are provided over misleading or no visuals. Further, eye-tracking data suggest that these visual representations may affect performance even when only briefly looked at. Implications for theories of fraction understanding and education are discussed. PsycINFO Database Record (c) 2016 APA, all rights reserved

  7. A Conceptual Schema Language for the Management of Multiple Representations of Geographic Entities

    DEFF Research Database (Denmark)

    Friis-Christensen, A.; Jensen, Christian Søndergaard; Nytun, J.P.

    2005-01-01

    Multiple representation of geographic information occurs when a real-world entity is represented more than once in the same or different databases. This occurs frequently in practice, and it invariably results in the occurrence of inconsistencies among the different representations of the same...... to specify rules that match objects representing the same entity, maintain consistency among these representations, and restore consistency if necessary. The rules configure a Multiple Representation Management System, the aim of which is to manage multiple representations over a number of autonomous...

  8. Understanding mid-level representations in visual processing

    Science.gov (United States)

    Peirce, Jonathan W.

    2015-01-01

    It is clear that early visual processing provides an image-based representation of the visual scene: Neurons in Striate cortex (V1) encode nothing about the meaning of a scene, but they do provide a great deal of information about the image features within it. The mechanisms of these “low-level” visual processes are relatively well understood. We can construct plausible models for how neurons, up to and including those in V1, build their representations from preceding inputs down to the level of photoreceptors. It is also clear that at some point we have a semantic, “high-level” representation of the visual scene because we can describe verbally the objects that we are viewing and their meaning to us. A huge number of studies are examining these “high-level” visual processes each year. Less well studied are the processes of “mid-level” vision, which presumably provide the bridge between these “low-level” representations of edges, colors, and lights and the “high-level” semantic representations of objects, faces, and scenes. This article and the special issue of papers in which it is published consider the nature of “mid-level” visual processing and some of the reasons why we might not have made as much progress in this domain as we would like. PMID:26053241

  9. Force Concept Inventory-Based Multiple-Choice Test for Investigating Students' Representational Consistency

    Science.gov (United States)

    Nieminen, Pasi; Savinainen, Antti; Viiri, Jouni

    2010-01-01

    This study investigates students' ability to interpret multiple representations consistently (i.e., representational consistency) in the context of the force concept. For this purpose we developed the Representational Variant of the Force Concept Inventory (R-FCI), which makes use of nine items from the 1995 version of the Force Concept Inventory…

  10. A Description Logic Based Knowledge Representation Model for Concept Understanding

    DEFF Research Database (Denmark)

    Badie, Farshad

    2018-01-01

    This research employs Description Logics in order to focus on logical description and analysis of the phenomenon of ‘concept understanding’. The article will deal with a formal-semantic model for figuring out the underlying logical assumptions of ‘concept understanding’ in knowledge representation...

  11. Foundation of a Knowledge Representation System for Image Understanding.

    Science.gov (United States)

    1980-10-01

    the tasks of the system is also basic in systems that use complete indexing, or Conniver, or Lisp. Systems like KRL [11], on the other hand, have a...Winograd, T., "An Overview of KRL , a Knowledge Representation Language," Cogn. Science, pp. 13-45, 1977. [12] Zadeh, L.A., "PRUF - A Memory

  12. Multiple representations and free-body diagrams: Do students benefit from using them?

    Science.gov (United States)

    Rosengrant, David R.

    2007-12-01

    Introductory physics students have difficulties understanding concepts and solving problems. When they solve problems, they use surface features of the problems to find an equation to calculate a numerical answer often not understanding the physics in the problem. How do we help students approach problem solving in an expert manner? A possible answer is to help them learn to represent knowledge in multiple ways and then use these different representations for conceptual understanding and problem solving. This solution follows from research in cognitive science and in physics education. However, there are no studies in physics that investigate whether students who learn to use multiple representations are in fact better problem solvers. This study focuses on one specific representation used in physics--a free body diagram. A free-body diagram is a graphical representation of forces exerted on an object of interest by other objects. I used the free-body diagram to investigate five main questions: (1) If students are in a course where they consistently use free body diagrams to construct and test concepts in mechanics, electricity and magnetism and to solve problems in class and in homework, will they draw free-body diagrams on their own when solving exam problems? (2) Are students who use free-body diagrams to solve problems more successful then those who do not? (3) Why do students draw free-body diagrams when solving problems? (4) Are students consistent in constructing diagrams for different concepts in physics and are they consistent in the quality of their diagrams? (5) What are possible relationships between features of a problem and how likely a student will draw a free body diagram to help them solve the problem? I utilized a mixed-methods approach to answer these questions. Questions 1, 2, 4 and 5 required a quantitative approach while question 3 required a qualitative approach, a case study. When I completed my study, I found that if students are in an

  13. A Markov chain representation of the multiple testing problem.

    Science.gov (United States)

    Cabras, Stefano

    2018-02-01

    The problem of multiple hypothesis testing can be represented as a Markov process where a new alternative hypothesis is accepted in accordance with its relative evidence to the currently accepted one. This virtual and not formally observed process provides the most probable set of non null hypotheses given the data; it plays the same role as Markov Chain Monte Carlo in approximating a posterior distribution. To apply this representation and obtain the posterior probabilities over all alternative hypotheses, it is enough to have, for each test, barely defined Bayes Factors, e.g. Bayes Factors obtained up to an unknown constant. Such Bayes Factors may either arise from using default and improper priors or from calibrating p-values with respect to their corresponding Bayes Factor lower bound. Both sources of evidence are used to form a Markov transition kernel on the space of hypotheses. The approach leads to easy interpretable results and involves very simple formulas suitable to analyze large datasets as those arising from gene expression data (microarray or RNA-seq experiments).

  14. How Should Intelligent Tutoring Systems Sequence Multiple Graphical Representations of Fractions? A Multi-Methods Study

    Science.gov (United States)

    Rau, M. A.; Aleven, V.; Rummel, N.; Pardos, Z.

    2014-01-01

    Providing learners with multiple representations of learning content has been shown to enhance learning outcomes. When multiple representations are presented across consecutive problems, we have to decide in what sequence to present them. Prior research has demonstrated that interleaving "tasks types" (as opposed to blocking them) can…

  15. Why Use Multiple Representations in the Mathematics Classroom? Views of English and German Preservice Teachers

    Science.gov (United States)

    Dreher, Anika; Kuntze, Sebastian; Lerman, Stephen

    2016-01-01

    Dealing with multiple representations and their connections plays a key role for learners to build up conceptual knowledge in the mathematics classroom. Hence, professional knowledge and views of mathematics teachers regarding the use of multiple representations certainly merit attention. In particular, investigating such views of preservice…

  16. Understanding media representations of homelessness in Metro Vancouver

    OpenAIRE

    Glover, Mary Ellen

    2010-01-01

    This project examines newsprint media’s coverage of homelessness in Metro Vancouver; specifically, documentation of its causes and solutions. I investigate how the media represented these, compared to causes and solutions proposed in the Regional Homelessness Plan, 3 Ways to Home: Housing, Income, and Support Services. This project includes an assessment of media representations-- causal attributions and proposed solutions/responses-- of homelessness and their potential to affect outcomes in ...

  17. Strongly and weakly directed approaches to teaching multiple representation use in physics

    Directory of Open Access Journals (Sweden)

    David Rosengrant

    2007-06-01

    Full Text Available Good use of multiple representations is considered key to learning physics, and so there is considerable motivation both to learn how students use multiple representations when solving problems and to learn how best to teach problem solving using multiple representations. In this study of two large-lecture algebra-based physics courses at the University of Colorado (CU and Rutgers, the State University of New Jersey, we address both issues. Students in each of the two courses solved five common electrostatics problems of varying difficulty, and we examine their solutions to clarify the relationship between multiple representation use and performance on problems involving free-body diagrams. We also compare our data across the courses, since the two physics-education-research-based courses take substantially different approaches to teaching the use of multiple representations. The course at Rutgers takes a strongly directed approach, emphasizing specific heuristics and problem-solving strategies. The course at CU takes a weakly directed approach, modeling good problem solving without teaching a specific strategy. We find that, in both courses, students make extensive use of multiple representations, and that this use (when both complete and correct is associated with significantly increased performance. Some minor differences in representation use exist, and are consistent with the types of instruction given. Most significant are the strong and broad similarities in the results, suggesting that either instructional approach or a combination thereof can be useful for helping students learn to use multiple representations for problem solving and concept development.

  18. Evidence for multiple, distinct representations of the human body.

    Science.gov (United States)

    Schwoebel, John; Coslett, H Branch

    2005-04-01

    Previous data from single-case and small group studies have suggested distinctions among structural, conceptual, and online sensorimotor representations of the human body. We developed a battery of tasks to further examine the prevalence and anatomic substrates of these body representations. The battery was administered to 70 stroke patients. Fifty-one percent of the patients were impaired relative to controls on at least one body representation measure. Further, principal components analysis of the patient data as well as direct comparisons of patient and control performance suggested a triple dissociation between measures of the 3 putative body representations. Consistent with previous distinctions between the "what" and "how" pathways, lesions of the left temporal lobe were most consistently associated with impaired performance on tasks assessing knowledge of the shape or lexical-semantic information about the body, whereas lesions of the dorsolateral frontal and parietal regions resulted in impaired performance on tasks requiring on-line coding of body posture.

  19. Effects of Representation Sequences and Spatial Ability on Students' Scientific Understandings about the Mechanism of Breathing

    Science.gov (United States)

    Wu, Hsin-Kai; Lin, Yu-Fen; Hsu, Ying-Shao

    2013-01-01

    The purpose of this study was to investigate the effects of representation sequences and spatial ability on students' scientific understandings about the mechanism of breathing in human beings. 130 seventh graders were assigned to two groups with different sequential combinations of static and dynamic representations: SD group (i.e., viewing…

  20. How to Make "More" Better? Principles for Effective Use of Multiple Representations to Enhance Students' Learning about Fractions

    Science.gov (United States)

    Rau, Martina A.; Matthews, Percival G.

    2017-01-01

    To make complex mathematics concepts accessible to students, teachers often rely on visual representations. Because no single representation can depict all aspects of a mathematics concept, instruction typically uses multiple representations. Much research shows that multiple representations can have immense benefits for students' learning.…

  1. Non-planar Feynman integrals, Mellin-Barnes representations, multiple sums

    Energy Technology Data Exchange (ETDEWEB)

    Bluemlein, Johannes; Dubovyk, Ievgen; Ochman, Michal; Raab, Clemens G.; Riemann, Tord [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany); Gluza, Janusz [Uniwersytet Slaski, Katowice (Poland). Inst. of Physics and Chemistry; Schneider, Carsten [Johannes Kepler Univ., Linz (Austria). Research Inst. for Symbolic Computation

    2014-07-15

    The construction of Mellin-Barnes (MB) representations for non-planar Feynman diagrams and the summation of multiple series derived from general MB representations are discussed. A basic version of a new package AMBREv.3.0 is supplemented. The ultimate goal of this project is the automatic evaluation of MB representations for multiloop scalar and tensor Feynman integrals through infinite sums, preferably with analytic solutions. We shortly describe a strategy of further algebraic summation.

  2. Analogical processes in children's understanding of spatial representations.

    Science.gov (United States)

    Yuan, Lei; Uttal, David; Gentner, Dedre

    2017-06-01

    We propose that map reading can be construed as a form of analogical mapping. We tested 2 predictions that follow from this claim: First, young children's patterns of performance in map reading tasks should parallel those found in analogical mapping tasks; and, second, children will benefit from guided alignment instructions that help them see the relational correspondences between the map and the space. In 4 experiments, 3-year-olds completed a map reading task in which they were asked to find hidden objects in a miniature room, using a corresponding map. We manipulated the availability of guided alignment (showing children the analogical mapping between maps and spaces; Experiments 1, 2, and 3a), the format of guided alignment (gesture or relational language; Experiment 2), and the iconicity of maps (Experiments 3a and 3b). We found that (a) young children's difficulties in map reading follow from known patterns of analogical development-for example, focusing on object similarity over relational similarity; and (b) guided alignment based on analogical reasoning led to substantially better performance. Results also indicated that children's map reading performance was affected by the format of guided alignment, the iconicity of the maps, and the order of tasks. The results bear on the developmental mechanisms underlying young children's learning of spatial representations and also suggest ways to support this learning. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  3. Representation of multiplication facts--evidence for partial verbal coding.

    Science.gov (United States)

    Moeller, Korbinian; Klein, Elise; Fischer, Martin H; Nuerk, Hans-Christoph; Willmes, Klaus

    2011-07-08

    The current view in numerical cognition research is that multiplication facts are stored and retrieved in a phonological code. Consistent with this view, it was found that multiplication could be impaired by a phonological but not by a visuo-spatial loading task. However, because the authors used an active production task, it remained unclear whether concurrent articulation impaired either access to multiplication facts or their retrieval. In the current study, we investigated the influence of concurrent articulation on multiplication fact knowledge without active production of multiplication results. In a number bisection task, number triplets, which are part of a multiplication table, were classified faster as being correctly bisected than other triplets. Interestingly, concurrent articulation led to a relative slowing of the multiplicative triplets which reduced the multiplicativity effect. This result indicates that concurrent articulation modulates access to phonologically stored multiplication facts and corroborates the notion of multiplication facts being represented in an at least partially verbal code.

  4. A Novel Technology to Investigate Students' Understandings of Enzyme Representations

    Science.gov (United States)

    Linenberger, Kimberly J.; Bretz, Stacey Lowery

    2012-01-01

    Digital pen-and-paper technology, although marketed commercially as a bridge between old and new note-taking capabilities, synchronizes the collection of both written and audio data. This manuscript describes how this technology was used to improve data collection in research regarding students' learning, specifically their understanding of…

  5. Research in Knowledge Representation for Natural Language Understanding

    Science.gov (United States)

    1983-10-01

    of RUS 157 157 160 161 SECTION 9. THE PRAGMATICS OF NON-ANAPHORIC NOUN PHRASES 9.1 Introduction 163 9.2 Setting the Stage: Previous views on... ANAPHORA , ELLIPSIS, DISCOURSE,... MRL DATA BASE TRANSLATOR DBMS COMMAND GENERATOR DBMS COMMANDS FIG. 1 ORGANIZATION OF THE IRUS SYSTEM 146...understanding system (such as semantics, pragmatics , and a dialogue expert) can be used to improve the performance of the parser. The production of the

  6. Representation of Multiplication Facts-Evidence for partial verbal coding

    Science.gov (United States)

    2011-01-01

    Background The current view in numerical cognition research is that multiplication facts are stored and retrieved in a phonological code. Consistent with this view, it was found that multiplication could be impaired by a phonological but not by a visuo-spatial loading task. However, because the authors used an active production task, it remained unclear whether concurrent articulation impaired either access to multiplication facts or their retrieval. Methods In the current study, we investigated the influence of concurrent articulation on multiplication fact knowledge without active production of multiplication results. Results In a number bisection task, number triplets, which are part of a multiplication table, were classified faster as being correctly bisected than other triplets. Interestingly, concurrent articulation led to a relative slowing of the multiplicative triplets which reduced the multiplicativity effect. Conclusions This result indicates that concurrent articulation modulates access to phonologically stored multiplication facts and corroborates the notion of multiplication facts being represented in an at least partially verbal code. PMID:21740568

  7. Representation of Multiplication Facts-Evidence for partial verbal coding

    OpenAIRE

    Moeller, Korbinian; Klein, Elise; Fischer, Martin H; Nuerk, Hans-Christoph; Willmes, Klaus

    2011-01-01

    Abstract Background The current view in numerical cognition research is that multiplication facts are stored and retrieved in a phonological code. Consistent with this view, it was found that multiplication could be impaired by a phonological but not by a visuo-spatial loading task. However, because the authors used an active production task, it remained unclear whether concurrent articulation impaired either access to multiplication facts or their retrieval. Methods In the current study, we ...

  8. Assessing Students' Understanding of Fraction Multiplication

    Science.gov (United States)

    Rumsey, Chepina; Guarino, Jody; Beltramini, Jennie; Cole, Shelbi; Farmer, Alicia; Gray, Kristin; Saxby, Morgan

    2016-01-01

    In this article the authors describe a project during which they unpacked fraction standards, created rigorous tasks and lesson plans, and developed formative and summative assessments to analyze students' thinking about fraction multiplication. The purpose of this article is to (1) illustrate a process that can be replicated by educators…

  9. Probabilistic image: a concise image representation technique for multiple parameters

    Energy Technology Data Exchange (ETDEWEB)

    Wu, L.C.; Yeh, S.H.; Liu, R.S. (Veterans General Hospital, Taiwan; National Yang-Mills Medical Coll., Taipei, Taiwan); Chen, Z. (National Chiao Tung Univ., Hsinchu, Taiwan)

    1984-09-01

    In scintiscanning studies, an attempt has been made to use multiple parametric information to evaluate functional abnormalities in human organs, using the probabilistic domain instead of the parametric domain to present single or multiple parameters in one image. The construction of such a probabilistic image (PBI) has been illustrated from a /sup 99/Tcsup(m)-HIDA study in 32 normal subjects and in 20 patients with intrahepatic lithiasis. The results show that this technique shows the functional abnormalities in a structural format with a good contrast and probabilistic sense.

  10. Knowledge representation to support reasoning based on multiple models

    Science.gov (United States)

    Gillam, April; Seidel, Jorge P.; Parker, Alice C.

    1990-01-01

    Model Based Reasoning is a powerful tool used to design and analyze systems, which are often composed of numerous interactive, interrelated subsystems. Models of the subsystems are written independently and may be used together while they are still under development. Thus the models are not static. They evolve as information becomes obsolete, as improved artifact descriptions are developed, and as system capabilities change. Researchers are using three methods to support knowledge/data base growth, to track the model evolution, and to handle knowledge from diverse domains. First, the representation methodology is based on having pools, or types, of knowledge from which each model is constructed. In addition information is explicit. This includes the interactions between components, the description of the artifact structure, and the constraints and limitations of the models. The third principle we have followed is the separation of the data and knowledge from the inferencing and equation solving mechanisms. This methodology is used in two distinct knowledge-based systems: one for the design of space systems and another for the synthesis of VLSI circuits. It has facilitated the growth and evolution of our models, made accountability of results explicit, and provided credibility for the user community. These capabilities have been implemented and are being used in actual design projects.

  11. Multiple kernel sparse representations for supervised and unsupervised learning.

    Science.gov (United States)

    Thiagarajan, Jayaraman J; Ramamurthy, Karthikeyan Natesan; Spanias, Andreas

    2014-07-01

    In complex visual recognition tasks, it is typical to adopt multiple descriptors, which describe different aspects of the images, for obtaining an improved recognition performance. Descriptors that have diverse forms can be fused into a unified feature space in a principled manner using kernel methods. Sparse models that generalize well to the test data can be learned in the unified kernel space, and appropriate constraints can be incorporated for application in supervised and unsupervised learning. In this paper, we propose to perform sparse coding and dictionary learning in the multiple kernel space, where the weights of the ensemble kernel are tuned based on graph-embedding principles such that class discrimination is maximized. In our proposed algorithm, dictionaries are inferred using multiple levels of 1D subspace clustering in the kernel space, and the sparse codes are obtained using a simple levelwise pursuit scheme. Empirical results for object recognition and image clustering show that our algorithm outperforms existing sparse coding based approaches, and compares favorably to other state-of-the-art methods.

  12. What are task-sets: a single, integrated representation or a collection of multiple control representations?

    Science.gov (United States)

    Rangelov, Dragan; Töllner, Thomas; Müller, Hermann J; Zehetleitner, Michael

    2013-01-01

    Performing two randomly alternating tasks typically results in higher reaction times (RTs) following a task switch, relative to a task repetition. These task switch costs (TSC) reflect processes of switching between control settings for different tasks. The present study investigated whether task sets operate as a single, integrated representation or as an agglomeration of relatively independent components. In a cued task switch paradigm, target detection (present/absent) and discrimination (blue/green/right-/left-tilted) tasks alternated randomly across trials. The target was either a color or an orientation singleton among homogeneous distractors. Across two trials, the task and target-defining dimension repeated or changed randomly. For task switch trials, agglomerated task sets predict a difference between dimension changes and repetitions: joint task and dimension switches require full task set reconfiguration, while dimension repetitions permit re-using some control settings from the previous trial. By contrast, integrated task sets always require full switches, predicting dimension repetition effects (DREs) to be absent across task switches. RT analyses showed significant DREs across task switches as well as repetitions supporting the notion of agglomerated task sets. Additionally, two event-related potentials (ERP) were analyzed: the Posterior-Contralateral-Negativity (PCN) indexing spatial selection dynamics, and the Sustained-Posterior-Contralateral-Negativity (SPCN) indexing post-selective perceptual/semantic analysis. Significant DREs across task switches were observed for both the PCN and SPCN components. Together, DREs across task switches for RTs and two functionally distinct ERP components suggest that re-using control settings across different tasks is possible. The results thus support the "agglomerated-task-set" hypothesis, and are inconsistent with "integrated task sets."

  13. What are task-sets: a single, integrated representation or a collection of multiple control representations?

    Directory of Open Access Journals (Sweden)

    Dragan eRangelov

    2013-09-01

    Full Text Available Performing two randomly alternating tasks typically results in higher reaction times (RTs following a task switch, relative to a task repetition. These task switch costs (TSC reflect processes of switching between control settings for different tasks. The present study investigated whether task sets operate as a single, integrated representation or as an agglomeration of relatively independent components. In a cued task switch paradigm, target detection (present/absent and discrimination (blue/green/right-/left-tilted tasks alternated randomly across trials. The target was either a color or an orientation singleton among homogeneous distractors. Across two trials, the task and target-defining dimension repeated or changed randomly. For task switch trials, agglomerated task sets predict a difference between dimension changes and repetitions: joint task and dimension switches require full task set reconfiguration, while dimension repetitions permit re-using some control settings from the previous trial. By contrast, integrated task sets always require full switches, predicting dimension repetition effects (DREs to be absent across task switches. RT analyses showed significant DREs across task switches as well as repetitions supporting the notion of agglomerated task sets. Additionally, two event-related potentials (ERP were analyzed: the Posterior-Contralateral-Negativity (PCN indexing spatial selection dynamics, and the Sustained-Posterior-Contralateral-Negativity (SPCN indexing post-selective perceptual/semantic analysis. Significant DREs across task switches were observed for both the PCN and SPCN components. Together, DREs across task switches for RTs and two functionally distinct ERP components suggest that re-using control settings across different tasks is possible. The results thus support the ‘agglomerated-task-set’ hypothesis, and are inconsistent with ‘integrated task sets’.

  14. Using Concrete & Representational Experiences to Understand the Structure of DNA: A Four-Step Instructional Framework

    Science.gov (United States)

    Harrell, Pamela Esprivalo; Richards, Debbie; Collins, James; Taylor, Sarah

    2005-01-01

    A description of learning experience that uses a four-step instrumentational framework involving concrete and representational experiences to promote conceptual understanding of abstract biological concepts by a series of closely-related activities is presented. The students are introduced to the structure and implications of DNA using four…

  15. Mathematics Teacher Candidates’ Multiple Representation and Conceptual-Procedural Knowledge Level in Definite Integral

    Directory of Open Access Journals (Sweden)

    Ali DELİCE

    2010-12-01

    Full Text Available Learning a subject conceptually requires establishing a relationship between the conceptual and the operational knowledge. Definite integral, being one of the topics of the calculus course is where learners face extensive learning difficulties mostly stemming from the lack of the knowledge of multiple representations. It is thought that the conceptual and the operational knowledge that mathematics teacher candidates influences the skill of using multiple representations. The study uses a case study approach which is based on an interpretivist qualitative paradigm. The participants of the study are 45 teacher candidates who are in their second year in the mathematics teacher training program of a state university. The data collection instruments were definite integral competency test, representation preference and transition test, semi structured interviews and document analysis. Findings suggest that algebraic representations are the dominant type in candidates’ solutions of integral problems. Candidates who are successful in terms of conceptual knowledge tend to use the representations more interrelated. Candidates who are successful in terms of operational knowledge tend mostly to use algebraic representations

  16. Maximum-margin based representation learning from multiple atlases for Alzheimer's disease classification.

    Science.gov (United States)

    Min, Rui; Cheng, Jian; Price, True; Wu, Guorong; Shen, Dinggang

    2014-01-01

    In order to establish the correspondences between different brains for comparison, spatial normalization based morphometric measurements have been widely used in the analysis of Alzheimer's disease (AD). In the literature, different subjects are often compared in one atlas space, which may be insufficient in revealing complex brain changes. In this paper, instead of deploying one atlas for feature extraction and classification, we propose a maximum-margin based representation learning (MMRL) method to learn the optimal representation from multiple atlases. Unlike traditional methods that perform the representation learning separately from the classification, we propose to learn the new representation jointly with the classification model, which is more powerful in discriminating AD patients from normal controls (NC). We evaluated the proposed method on the ADNI database, and achieved 90.69% for AD/NC classification and 73.69% for p-MCI/s-MCI classification.

  17. Emotion understanding, pictorial representations of friendship and reciprocity in school-aged children.

    Science.gov (United States)

    Laghi, Fiorenzo; Baiocco, Roberto; Di Norcia, Anna; Cannoni, Eleonora; Baumgartner, Emma; Bombi, Anna Silvia

    2014-01-01

    This study examined the relationship between emotional understanding, friendship representation and reciprocity in school-aged children. Two hundred and fifty-one Caucasian 6-year-old children (111 males and 140 females) took part in the study. The Test of Emotion Comprehension (TEC) and the Pictorial Assessment of Interpersonal Relationships (PAIR) were used. Children having a reciprocal friendship and children having a unilateral friendship with a child named as their "best friend" were compared on the emotional understanding task and on their pictorial representations of friendship. Multilevel analyses indicated that friendship status effects were not influenced by classroom-level differences. Results showed that children with reciprocal friendships drew themselves as more similar to and more cohesive with their best friends, and they showed better understanding of emotions, than children having a unilateral friendship. Finally, the implications of these findings for theoretical and empirical research development on friendship are discussed.

  18. How online learning modules can improve the representational fluency and conceptual understanding of university physics students

    Science.gov (United States)

    Hill, M.; Sharma, M. D.; Johnston, H.

    2015-07-01

    The use of online learning resources as core components of university science courses is increasing. Learning resources range from summaries, videos, and simulations, to question banks. Our study set out to develop, implement, and evaluate research-based online learning resources in the form of pre-lecture online learning modules (OLMs). The aim of this paper is to share our experiences with those using, or considering implementing, online learning resources. Our first task was to identify student learning issues in physics to base the learning resources on. One issue with substantial research is conceptual understanding, the other with comparatively less research is scientific representations (graphs, words, equations, and diagrams). We developed learning resources on both these issues and measured their impact. We created weekly OLMs which were delivered to first year physics students at The University of Sydney prior to their first lecture of the week. Students were randomly allocated to either a concepts stream or a representations stream of online modules. The programme was first implemented in 2013 to trial module content, gain experience and process logistical matters and repeated in 2014 with approximately 400 students. Two validated surveys, the Force and Motion Concept Evaluation (FMCE) and the Representational Fluency Survey (RFS) were used as pre-tests and post-tests to measure learning gains while surveys and interviews provided further insights. While both streams of OLMs produced similar positive learning gains on the FMCE, the representations-focussed OLMs produced higher gains on the RFS. Conclusions were triangulated with student responses which indicated that they have recognized the benefit of the OLMs for their learning of physics. Our study shows that carefully designed online resources used as pre-instruction can make a difference in students’ conceptual understanding and representational fluency in physics, as well as make them more aware

  19. A Conceptual Framework for Error Remediation with Multiple External Representations Applied to Learning Objects

    Science.gov (United States)

    Leite, Maici Duarte; Marczal, Diego; Pimentel, Andrey Ricardo; Direne, Alexandre Ibrahim

    2014-01-01

    This paper presents the application of some concepts of Intelligent Tutoring Systems (ITS) to elaborate a conceptual framework that uses the remediation of errors with Multiple External Representations (MERs) in Learning Objects (LO). To this is demonstrated a development of LO for teaching the Pythagorean Theorem through this framework. This…

  20. Parameter Effects and Solving Linear Equations in Dynamic, Linked, Multiple Representation Environments.

    Science.gov (United States)

    Lin, Pao-Ping; Hsieh, Che-Jen

    1993-01-01

    Describes the Geometer's Sketchpad, a geometric construction kit composed of three manipulatable, dynamic, linked, multiple representation environments: the coordinate system, formulas, and graphs. Examines the use of the environments for studying parameter effects of linear and quadratic functions and for solving linear equations. (MDH)

  1. An Investigation of Pattern Problems Posed by Middle School Mathematics Preservice Teachers Using Multiple Representation

    Science.gov (United States)

    Yilmaz, Yasemin; Durmus, Soner; Yaman, Hakan

    2018-01-01

    This study investigated the pattern problems posed by middle school mathematics preservice teachers using multiple representations to determine both their pattern knowledge levels and their abilities to transfer this knowledge to students. The design of the study is the survey method, one of the quantitative research methods. The study group was…

  2. Supporting Students in Learning with Multiple Representation to Improve Student Mental Models on Atomic Structure Concepts

    Science.gov (United States)

    Sunyono; Yuanita, L.; Ibrahim, M.

    2015-01-01

    The aim of this research is identify the effectiveness of a multiple representation-based learning model, which builds a mental model within the concept of atomic structure. The research sample of 108 students in 3 classes is obtained randomly from among students of Mathematics and Science Education Studies using a stratified random sampling…

  3. ShapeShop: Towards Understanding Deep Learning Representations via Interactive Experimentation.

    Science.gov (United States)

    Hohman, Fred; Hodas, Nathan; Chau, Duen Horng

    2017-05-01

    Deep learning is the driving force behind many recent technologies; however, deep neural networks are often viewed as "black-boxes" due to their internal complexity that is hard to understand. Little research focuses on helping people explore and understand the relationship between a user's data and the learned representations in deep learning models. We present our ongoing work, ShapeShop, an interactive system for visualizing and understanding what semantics a neural network model has learned. Built using standard web technologies, ShapeShop allows users to experiment with and compare deep learning models to help explore the robustness of image classifiers.

  4. ShapeShop: Towards Understanding Deep Learning Representations via Interactive Experimentation

    Energy Technology Data Exchange (ETDEWEB)

    Hohman, Frederick M.; Hodas, Nathan O.; Chau, Duen Horng

    2017-05-30

    Deep learning is the driving force behind many recent technologies; however, deep neural networks are often viewed as “black-boxes” due to their internal complexity that is hard to understand. Little research focuses on helping people explore and understand the relationship between a user’s data and the learned representations in deep learning models. We present our ongoing work, ShapeShop, an interactive system for visualizing and understanding what semantics a neural network model has learned. Built using standard web technologies, ShapeShop allows users to experiment with and compare deep learning models to help explore the robustness of image classifiers.

  5. SAR Target Recognition Based on Multi-feature Multiple Representation Classifier Fusion

    Directory of Open Access Journals (Sweden)

    Zhang Xinzheng

    2017-10-01

    Full Text Available In this paper, we present a Synthetic Aperture Radar (SAR image target recognition algorithm based on multi-feature multiple representation learning classifier fusion. First, it extracts three features from the SAR images, namely principal component analysis, wavelet transform, and Two-Dimensional Slice Zernike Moments (2DSZM features. Second, we harness the sparse representation classifier and the cooperative representation classifier with the above-mentioned features to get six predictive labels. Finally, we adopt classifier fusion to obtain the final recognition decision. We researched three different classifier fusion algorithms in our experiments, and the results demonstrate thatusing Bayesian decision fusion gives thebest recognition performance. The method based on multi-feature multiple representation learning classifier fusion integrates the discrimination of multi-features and combines the sparse and cooperative representation classification performance to gain complementary advantages and to improve recognition accuracy. The experiments are based on the Moving and Stationary Target Acquisition and Recognition (MSTAR database,and they demonstrate the effectiveness of the proposed approach.

  6. Representation of Students in Solving Simultaneous Linear Equation Problems Based on Multiple Intelligence

    Science.gov (United States)

    Yanti, Y. R.; Amin, S. M.; Sulaiman, R.

    2018-01-01

    This study described representation of students who have musical, logical-mathematic and naturalist intelligence in solving a problem. Subjects were selected on the basis of multiple intelligence tests (TPM) consists of 108 statements, with 102 statements adopted from Chislet and Chapman and 6 statements equal to eksistensial intelligences. Data were analyzed based on problem-solving tests (TPM) and interviewing. See the validity of the data then problem-solving tests (TPM) and interviewing is given twice with an analyzed using the representation indikator and the problem solving step. The results showed that: the stage of presenting information known, stage of devising a plan, and stage of carrying out the plan those three subjects were using same form of representation. While he stage of presenting information asked and stage of looking back, subject of logical-mathematic was using different forms of representation with subjects of musical and naturalist intelligence. From this research is expected to provide input to the teacher in determining the learning strategy that will be used by considering the representation of students with the basis of multiple intelligences.

  7. Conceptual Understanding of Multiplicative Properties through Endogenous Digital Game Play

    Science.gov (United States)

    Denham, Andre

    2012-01-01

    This study purposed to determine the effect of an endogenously designed instructional game on conceptual understanding of the associative and distributive properties of multiplication. Additional this study sought to investigate if performance on measures of conceptual understanding taken prior to and after game play could serve as predictors of…

  8. Learning with multiple representations: an example of a revision lesson in mechanics

    Science.gov (United States)

    Wong, Darren; Poo, Sng Peng; Eng Hock, Ng; Loo Kang, Wee

    2011-03-01

    We describe an example of learning with multiple representations in an A-level revision lesson on mechanics. The context of the problem involved the motion of a ball thrown vertically upwards in air and studying how the associated physical quantities changed during its flight. Different groups of students were assigned to look at the ball's motion using various representations: motion diagrams, vector diagrams, free-body diagrams, verbal description, equations and graphs, drawn against time as well as against displacement. Overall, feedback from students about the lesson was positive. We further discuss the benefits of using computer simulation to support and extend student learning.

  9. Students' Representational Fluency at University: A Cross-Sectional Measure of How Multiple Representations Are Used by Physics Students Using the Representational Fluency Survey

    Science.gov (United States)

    Hill, Matthew; Sharma, Manjula Devi

    2015-01-01

    To succeed within scientific disciplines, using representations, including those based on words, graphs, equations, and diagrams, is important. Research indicates that the use of discipline specific representations (sometimes referred to as expert generated representations), as well as multi-representational use, is critical for problem solving…

  10. Multiple levels of letter representation in written spelling: evidence from a single case of dysgraphia with multiple deficits.

    Science.gov (United States)

    de Partz, Marie-Pierre; Lochy, Aliette; Pillon, Agnesa

    2005-01-01

    In this paper, we report a detailed analysis of the impaired performance of a dysgraphic individual, AD, who produced similar rates of letter-level errors in written spelling, oral spelling, and typing. We found that the distribution of various letter error types displayed a distinct pattern in written spelling on the one hand and in oral spelling and typing on the other. In particular, noncontextual letter substitution errors (i.e., errors in which the erroneous letter that replaces the target letter does not occur elsewhere within the word) were virtually absent in oral spelling and typing and mainly found in written spelling. In contrast, letter deletion errors and multiple-letter errors were typically found in oral spelling and very exceptional in written spelling. Only contextual letter substitution errors (i.e., errors in which the erroneous letter that replaces the target letter is identical to a letter occurring earlier or later in the word) were found in similar proportions in the three tasks. We argue that these contrasting patterns of letter error distribution result from damage to two distinct levels of letter representation and processing within the spelling system, namely, the amodal graphemic representation held in the graphemic buffer and the letter form representation computed by subsequent writing-specific processes. Then, we examined the relationship between error and target in the letter substitution errors produced in written and oral spelling and found evidence that distinct types of letter representation are processed at each of the hypothetized levels of damage: symbolic letter representation at the graphemic level and representation of the component graphic strokes at the letter form processing level.

  11. Multiple Levels of Letter Representation in Written Spelling: Evidence From a Single Case of Dysgraphia with Multiple Deficits

    Directory of Open Access Journals (Sweden)

    Marie-Pierre de Partz

    2005-01-01

    Full Text Available In this paper, we report a detailed analysis of the impaired performance of a dysgraphic individual, AD, who produced similar rates of letter-level errors in written spelling, oral spelling, and typing. We found that the distribution of various letter error types displayed a distinct pattern in written spelling on the one hand and in oral spelling and typing on the other. In particular, noncontextual letter substitution errors (i.e., errors in which the erroneous letter that replaces the target letter does not occur elsewhere within the word were virtually absent in oral spelling and typing and mainly found in written spelling. In contrast, letter deletion errors and multiple-letter errors were typically found in oral spelling and very exceptional in written spelling. Only contextual letter substitution errors (i.e., errors in which the erroneous letter that replaces the target letter is identical to a letter occurring earlier or later in the word were found in similar proportions in the three tasks. We argue that these contrasting patterns of letter error distribution result from damage to two distinct levels of letter representation and processing within the spelling system, namely, the amodal graphemic representation held in the graphemic buffer and the letter form representation computed by subsequent writing-specific processes. Then, we examined the relationship between error and target in the letter substitution errors produced in written and oral spelling and found evidence that distinct types of letter representation are processed at each of the hypothetized levels of damage: symbolic letter representation at the graphemic level and representation of the component graphic strokes at the letter form processing level.

  12. Theoretical-methodological approach to social imaginary and collective representations: Notes for a sociological understanding of image

    Directory of Open Access Journals (Sweden)

    Jorge Eliécer Martínez Posada

    2009-01-01

    Full Text Available The study of social imaginaries and collective representations from a sociological perspective involves agencying interpretative exercises of image reconstruction, whether mental or pictorial images. Thus, the theoretical path followed in this text points to the understanding of social imaginaries and collective representations, as knowledge tradition socially constructed, and social images, which become historically symbolic points of reference of social action.

  13. A Case Study of Preservice Science Teachers with Different Argumentation Understandings: Their Views and Practices of Using Representations in Argumentation

    Science.gov (United States)

    Namdar, Bahadir

    2017-01-01

    Representations are fundamental tools to support argumentation in science learning. However, little is known about how preservice science teachers (PSTs) with different argumentation understandings view and use representations in argumentation. Therefore, the purpose of this case study was to explore the views and practices of PSTs' use of…

  14. A framework for understanding the conditions of science representation and dissemination in museums

    DEFF Research Database (Denmark)

    Achiam, Marianne; Marandino, Martha

    2014-01-01

    Museums are in a unique position to engage the public in conversations about science topics that matter. However, when we attempt to systematically study the representation and dissemination of science in museums, we are confounded by the numerous and diverse conditions and constraints...... that influence those processes. As a response, we adapt a framework from the field of science didactics, the framework of didactic co-determination, to the museum context. We illustrate how the framework can be applied to a case of exhibit development to understand the influences that shape the final product. We...

  15. Using digital technologies to enhance chemistry students' understanding and representational skills

    DEFF Research Database (Denmark)

    Hilton, Annette

    Abstract Chemistry students need to understand chemistry on molecular, symbolic and macroscopic levels. Students find it difficult to use representations on these three levels to interpret and explain data. One approach is to encourage students to use writing-to-learn strategies in inquiry settings...... to present and interpret their laboratory results. This paper describes findings from a study on the effects on students’ learning outcomes of creating multimodal texts to report on laboratory inquiries. The study involved two senior secondary school chemistry classes (n = 22, n = 27). Both classes completed...

  16. At the mercy of strategies: the role of motor representations in language understanding

    Directory of Open Access Journals (Sweden)

    Barbara eTomasino

    2013-02-01

    Full Text Available Classical cognitive theories hold that word representations in the brain are abstract and amodal, and are independent of the objects’ sensorimotor properties they refer to. An alternative hypothesis emphasises the importance of bodily processes in cognition: the representation of a concept appears to be crucially dependent upon perceptual-motor processes that relate to it. Thus, understanding action-related words would rely upon the same motor structures that also support the execution of the same actions. In this context, motor simulation represents a key component. Our approach is to draw parallels between the literature on mental rotation and the literature on action verb/sentence processing. Here we will discuss recent studies on mental imagery, mental rotation, and language that clearly demonstrate how motor simulation is neither automatic nor necessary to language understanding. These studies have shown that motor representations can or cannot be activated depending on the type of strategy the participants adopt to perform tasks involving motor phrases. On the one hand, participants may imagine the movement with the body parts used to carry out the actions described by the verbs (i.e., motor strategy; on the other, individuals may solve the task without simulating the corresponding movements (i.e., visual strategy. While it is not surprising that the motor strategy is at work when participants process action-related verbs, it is however striking that sensorimotor activation has been reported also for imageable concrete words with no motor content, for non-words with regular phonology, for pseudo-verb stimuli, and also for negations. Based on the extant literature, we will argue that implicit motor imagery is not uniquely used when a body-related stimulus is encountered, and that it is not the type of stimulus that automatically triggers the motor simulation but the type of strategy. Finally, we will also comment on the view that

  17. The Effects of Visual Cues and Learners' Field Dependence in Multiple External Representations Environment for Novice Program Comprehension

    Science.gov (United States)

    Wei, Liew Tze; Sazilah, Salam

    2012-01-01

    This study investigated the effects of visual cues in multiple external representations (MER) environment on the learning performance of novices' program comprehension. Program codes and flowchart diagrams were used as dual representations in multimedia environment to deliver lessons on C-Programming. 17 field independent participants and 16 field…

  18. Improving Conceptual Understanding and Representation Skills Through Excel-Based Modeling

    Science.gov (United States)

    Malone, Kathy L.; Schunn, Christian D.; Schuchardt, Anita M.

    2018-02-01

    The National Research Council framework for science education and the Next Generation Science Standards have developed a need for additional research and development of curricula that is both technologically model-based and includes engineering practices. This is especially the case for biology education. This paper describes a quasi-experimental design study to test the effectiveness of a model-based curriculum focused on the concepts of natural selection and population ecology that makes use of Excel modeling tools (Modeling Instruction in Biology with Excel, MBI-E). The curriculum revolves around the bio-engineering practice of controlling an invasive species. The study takes place in the Midwest within ten high schools teaching a regular-level introductory biology class. A post-test was designed that targeted a number of common misconceptions in both concept areas as well as representational usage. The results of a post-test demonstrate that the MBI-E students significantly outperformed the traditional classes in both natural selection and population ecology concepts, thus overcoming a number of misconceptions. In addition, implementing students made use of more multiple representations as well as demonstrating greater fascination for science.

  19. The unique and shared contributions of arithmetic operation understanding and numerical magnitude representation to children's mathematics achievement.

    Science.gov (United States)

    Wong, Terry Tin-Yau

    2017-12-01

    The current study examined the unique and shared contributions of arithmetic operation understanding and numerical magnitude representation to children's mathematics achievement. A sample of 124 fourth graders was tested on their arithmetic operation understanding (as reflected by their understanding of arithmetic principles and the knowledge about the application of arithmetic operations) and their precision of rational number magnitude representation. They were also tested on their mathematics achievement and arithmetic computation performance as well as the potential confounding factors. The findings suggested that both arithmetic operation understanding and numerical magnitude representation uniquely predicted children's mathematics achievement. The findings highlight the significance of arithmetic operation understanding in mathematics learning. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. Learning Enhances Sensory and Multiple Non-sensory Representations in Primary Visual Cortex.

    Science.gov (United States)

    Poort, Jasper; Khan, Adil G; Pachitariu, Marius; Nemri, Abdellatif; Orsolic, Ivana; Krupic, Julija; Bauza, Marius; Sahani, Maneesh; Keller, Georg B; Mrsic-Flogel, Thomas D; Hofer, Sonja B

    2015-06-17

    We determined how learning modifies neural representations in primary visual cortex (V1) during acquisition of a visually guided behavioral task. We imaged the activity of the same layer 2/3 neuronal populations as mice learned to discriminate two visual patterns while running through a virtual corridor, where one pattern was rewarded. Improvements in behavioral performance were closely associated with increasingly distinguishable population-level representations of task-relevant stimuli, as a result of stabilization of existing and recruitment of new neurons selective for these stimuli. These effects correlated with the appearance of multiple task-dependent signals during learning: those that increased neuronal selectivity across the population when expert animals engaged in the task, and those reflecting anticipation or behavioral choices specifically in neuronal subsets preferring the rewarded stimulus. Therefore, learning engages diverse mechanisms that modify sensory and non-sensory representations in V1 to adjust its processing to task requirements and the behavioral relevance of visual stimuli. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

  1. A multiple distributed representation method based on neural network for biomedical event extraction.

    Science.gov (United States)

    Wang, Anran; Wang, Jian; Lin, Hongfei; Zhang, Jianhai; Yang, Zhihao; Xu, Kan

    2017-12-20

    Biomedical event extraction is one of the most frontier domains in biomedical research. The two main subtasks of biomedical event extraction are trigger identification and arguments detection which can both be considered as classification problems. However, traditional state-of-the-art methods are based on support vector machine (SVM) with massive manually designed one-hot represented features, which require enormous work but lack semantic relation among words. In this paper, we propose a multiple distributed representation method for biomedical event extraction. The method combines context consisting of dependency-based word embedding, and task-based features represented in a distributed way as the input of deep learning models to train deep learning models. Finally, we used softmax classifier to label the example candidates. The experimental results on Multi-Level Event Extraction (MLEE) corpus show higher F-scores of 77.97% in trigger identification and 58.31% in overall compared to the state-of-the-art SVM method. Our distributed representation method for biomedical event extraction avoids the problems of semantic gap and dimension disaster from traditional one-hot representation methods. The promising results demonstrate that our proposed method is effective for biomedical event extraction.

  2. Towards a better understanding of people's responses to renewable energy technologies: Insights from Social Representations Theory.

    Science.gov (United States)

    Batel, Susana; Devine-Wright, Patrick

    2015-04-01

    In the past few years, social research has been examining what contributes to the attitude-behaviour gap in people's responses to large-scale renewable energy technologies. The NIMBY explanation for the gap has long dominated that area of research, but has also been criticised. Alternative proposals to NIMBY were advanced, but it is still evident that some of those maintain presuppositions of NIMBY and that this area of research needs more integration, namely at a theoretical level. In this paper we argue that to overcome those aspects it is relevant, first, to situate the promotion of renewable energy production as a social change process in today's societies, and, second, to therefore consider the socio-psychological aspects involved in people's responses to social change. We discuss specifically how the Theory of Social Representations may help us with that and contribute to a better understanding of people's responses to renewable energy technologies. © The Author(s) 2014.

  3. Generating Multiple Base-Resolution DNA Methylomes Using Reduced Representation Bisulfite Sequencing.

    Science.gov (United States)

    Chatterjee, Aniruddha; Rodger, Euan J; Stockwell, Peter A; Le Mée, Gwenn; Morison, Ian M

    2017-01-01

    Reduced representation bisulfite sequencing (RRBS) is an effective technique for profiling genome-wide DNA methylation patterns in eukaryotes. RRBS couples size selection, bisulfite conversion, and second-generation sequencing to enrich for CpG-dense regions of the genome. The progressive improvement of second-generation sequencing technologies and reduction in cost provided an opportunity to examine the DNA methylation patterns of multiple genomes. Here, we describe a protocol for sequencing multiple RRBS libraries in a single sequencing reaction to generate base-resolution methylomes. Furthermore, we provide a brief guideline for base-calling and data analysis of multiplexed RRBS libraries. These strategies will be useful to perform large-scale, genome-wide DNA methylation analysis.

  4. Newton’s Cradle Experiment Using Video Tracking Analysis with Multiple Representation Approach

    Science.gov (United States)

    Anissofira, A.; Latief, F. D. E.; Kholida, L.; Sinaga, P.

    2017-09-01

    This paper reports a Physics lesson using video tracking analysis applied in Newton’s Cradle experiment to train student’s multiple representation skill. This study involved 30 science high school students from class XI. In this case, Tracker software was used to verify energy conservation law, with help from data result such as graphs and tables. Newton’s Cradle is commonly used to demonstrate the law of energy and momentum conservation. It consists of swinging spherical bobs which transfers energy from one to another by means of elastic collisions. From the video analysis, it is found that there is a difference in the velocity of the two bobs of opposite ends. Furthermore, investigation of what might cause it to happen can be done by observing and analysing the recorded video. This paper discusses students’ response and teacher’s reflection after using Tracker video analysis software in the Physics lesson. Since Tracker has the ability to provide us with multiple means of data representation way, we conclude that this method could be a good alternative solution and might also be considered better than performing a hands-on experiment activity in which not every school have suitable laboratory equipment.

  5. Problem solving based learning model with multiple representations to improve student's mental modelling ability on physics

    Science.gov (United States)

    Haili, Hasnawati; Maknun, Johar; Siahaan, Parsaoran

    2017-08-01

    Physics is a lessons that related to students' daily experience. Therefore, before the students studying in class formally, actually they have already have a visualization and prior knowledge about natural phenomenon and could wide it themselves. The learning process in class should be aimed to detect, process, construct, and use students' mental model. So, students' mental model agree with and builds in the right concept. The previous study held in MAN 1 Muna informs that in learning process the teacher did not pay attention students' mental model. As a consequence, the learning process has not tried to build students' mental modelling ability (MMA). The purpose of this study is to describe the improvement of students' MMA as a effect of problem solving based learning model with multiple representations approach. This study is pre experimental design with one group pre post. It is conducted in XI IPA MAN 1 Muna 2016/2017. Data collection uses problem solving test concept the kinetic theory of gasses and interview to get students' MMA. The result of this study is clarification students' MMA which is categorized in 3 category; High Mental Modelling Ability (H-MMA) for 7MMA) for 3MMA) for 0 ≤ x ≤ 3 score. The result shows that problem solving based learning model with multiple representations approach can be an alternative to be applied in improving students' MMA.

  6. A design study to develop young children's understanding of multiplication and division

    Science.gov (United States)

    Bicknell, Brenda; Young-Loveridge, Jenny; Nguyen, Nhung

    2016-12-01

    This design study investigated the use of multiplication and division problems to help 5-year-old children develop an early understanding of multiplication and division. One teacher and her class of 15 5-year-old children were involved in a collaborative partnership with the researchers. The design study was conducted over two 4-week periods in May-June and October-November. The focus in this article is on three key aspects of classroom teaching: instructional tasks, the use of representations, and discourse, including the mathematics register. Results from selected pre- and post-assessment tasks within a diagnostic interview showed that there were improvements in addition and subtraction as well as multiplication and division, even though the teaching had used multiplication and division problems. Students made progress on all four operational domains, with effect sizes ranging from approximately two thirds of a standard deviation to 2 standard deviations. Most of the improvement in students' number strategies was in moving from `counting all' to `counting on' and `skip counting'. The findings challenge the idea that learning experiences in addition and subtraction should precede those in multiplication and division as suggested in some curriculum documents.

  7. Asymmetric activation spreading in the multiplication associative network due to asymmetric overlap between numerosities semantic representations?

    Science.gov (United States)

    Didino, Daniele; Knops, André; Vespignani, Francesco; Kornpetpanee, Suchada

    2015-08-01

    Simple multiplication facts are thought to be organised in a network structure in which problems and solutions are associated. Converging evidence suggests that the ability for solving symbolic arithmetic problems is based on an approximate number system (ANS). Most theoretical stances concerning the metric underlying the ANS converge on the assumption that the representational overlap between two adjacent numbers increases as the numerical magnitude of the numbers increases. Given a number N, the overlap between N and N+1 is larger than the overlap between N and N-1. Here, we test whether this asymmetric overlap influences the activation spreading within the multiplication associative network (MAN). When verifying simple multiplication problems such as 8×4 participants were slower in rejecting false but related outcomes that were larger than the actual outcome (e.g., 8×4=36) than rejecting smaller related outcomes (e.g., 8×4=28), despite comparable numerical distance from the correct result (here: 4). This effect was absent for outcomes which are not part of either operands table (e.g., 8×4=35). These results suggest that the metric of the ANS influences the activation spreading within the MAN, further substantiating the notion that symbolic arithmetic is grounded in the ANS. Copyright © 2015 Elsevier B.V. All rights reserved.

  8. Stimulus-response bindings code both abstract and specific representations of stimuli: evidence from a classification priming design that reverses multiple levels of response representation.

    Science.gov (United States)

    Horner, A J; Henson, R N

    2011-11-01

    Repetition priming can be caused by the rapid retrieval of previously encoded stimulus-response (S-R) bindings. S-R bindings have recently been shown to simultaneously code multiple levels of response representation, from specific Motor-actions to more abstract Decisions ("yes"/"no") and Classifications (e.g., "man-made"/"natural"). Using an experimental design that reverses responses at all of these levels, we assessed whether S-R bindings also code multiple levels of stimulus representation. Across two experiments, we found effects of response reversal on priming when switching between object pictures and object names, consistent with S-R bindings that code stimuli at an abstract level. Nonetheless, the size of this reversal effect was smaller for such across-format (e.g., word-picture) repetition than for within-format (e.g., picture-picture) repetition, suggesting additional coding of format-specific stimulus representations. We conclude that S-R bindings simultaneously represent both stimuli and responses at multiple levels of abstraction.

  9. The Errors of Our Ways: Understanding Error Representations in Cerebellar-Dependent Motor Learning.

    Science.gov (United States)

    Popa, Laurentiu S; Streng, Martha L; Hewitt, Angela L; Ebner, Timothy J

    2016-04-01

    The cerebellum is essential for error-driven motor learning and is strongly implicated in detecting and correcting for motor errors. Therefore, elucidating how motor errors are represented in the cerebellum is essential in understanding cerebellar function, in general, and its role in motor learning, in particular. This review examines how motor errors are encoded in the cerebellar cortex in the context of a forward internal model that generates predictions about the upcoming movement and drives learning and adaptation. In this framework, sensory prediction errors, defined as the discrepancy between the predicted consequences of motor commands and the sensory feedback, are crucial for both on-line movement control and motor learning. While many studies support the dominant view that motor errors are encoded in the complex spike discharge of Purkinje cells, others have failed to relate complex spike activity with errors. Given these limitations, we review recent findings in the monkey showing that complex spike modulation is not necessarily required for motor learning or for simple spike adaptation. Also, new results demonstrate that the simple spike discharge provides continuous error signals that both lead and lag the actual movements in time, suggesting errors are encoded as both an internal prediction of motor commands and the actual sensory feedback. These dual error representations have opposing effects on simple spike discharge, consistent with the signals needed to generate sensory prediction errors used to update a forward internal model.

  10. The multiple self-aspects framework: self-concept representation and its implications.

    Science.gov (United States)

    McConnell, Allen R

    2011-02-01

    The multiple self-aspects framework (MSF) conceives of the self-concept as a collection of multiple, context-dependent selves. From this perspective, five principles are derived, addressing issues such as how context activates particular regions of self-knowledge and how self-relevant feedback affects self-evaluations and affect. Support for these principles is discussed. Furthermore, the MSF advances several novel predictions, including how active self-aspects filter one's experiences and perceptions, how the impact of chronic accessibility is more circumscribed than previously realized, and how self-concept representation modulates the experience of affect. In addition, the MSF helps integrate isolated lines of research within several diverse literatures, including self-regulation, stability and variability for the self, the integration of others into the self-concept, and several individual difference factors as well. Overall, the current work speaks to issues of relevance to several subdisciplines in psychology (e.g., cultural, developmental, personality, social) interested in the self, providing conceptual and methodological insights.

  11. Information Compression, Multiple Alignment, and the Representation and Processing of Knowledge in the Brain.

    Science.gov (United States)

    Wolff, J Gerard

    2016-01-01

    The SP theory of intelligence , with its realization in the SP computer model , aims to simplify and integrate observations and concepts across artificial intelligence, mainstream computing, mathematics, and human perception and cognition, with information compression as a unifying theme. This paper describes how abstract structures and processes in the theory may be realized in terms of neurons, their interconnections, and the transmission of signals between neurons. This part of the SP theory- SP-neural -is a tentative and partial model for the representation and processing of knowledge in the brain. Empirical support for the SP theory-outlined in the paper-provides indirect support for SP-neural. In the abstract part of the SP theory (SP-abstract), all kinds of knowledge are represented with patterns , where a pattern is an array of atomic symbols in one or two dimensions. In SP-neural, the concept of a "pattern" is realized as an array of neurons called a pattern assembly , similar to Hebb's concept of a "cell assembly" but with important differences. Central to the processing of information in SP-abstract is information compression via the matching and unification of patterns (ICMUP) and, more specifically, information compression via the powerful concept of multiple alignment , borrowed and adapted from bioinformatics. Processes such as pattern recognition, reasoning and problem solving are achieved via the building of multiple alignments, while unsupervised learning is achieved by creating patterns from sensory information and also by creating patterns from multiple alignments in which there is a partial match between one pattern and another. It is envisaged that, in SP-neural, short-lived neural structures equivalent to multiple alignments will be created via an inter-play of excitatory and inhibitory neural signals. It is also envisaged that unsupervised learning will be achieved by the creation of pattern assemblies from sensory information and from the

  12. Sepsis: Multiple Abnormalities, Heterogeneous Responses, and Evolving Understanding

    Science.gov (United States)

    Iskander, Kendra N.; Osuchowski, Marcin F.; Stearns-Kurosawa, Deborah J.; Kurosawa, Shinichiro; Stepien, David; Valentine, Catherine

    2013-01-01

    Sepsis represents the host's systemic inflammatory response to a severe infection. It causes substantial human morbidity resulting in hundreds of thousands of deaths each year. Despite decades of intense research, the basic mechanisms still remain elusive. In either experimental animal models of sepsis or human patients, there are substantial physiological changes, many of which may result in subsequent organ injury. Variations in age, gender, and medical comorbidities including diabetes and renal failure create additional complexity that influence the outcomes in septic patients. Specific system-based alterations, such as the coagulopathy observed in sepsis, offer both potential insight and possible therapeutic targets. Intracellular stress induces changes in the endoplasmic reticulum yielding misfolded proteins that contribute to the underlying pathophysiological changes. With these multiple changes it is difficult to precisely classify an individual's response in sepsis as proinflammatory or immunosuppressed. This heterogeneity also may explain why most therapeutic interventions have not improved survival. Given the complexity of sepsis, biomarkers and mathematical models offer potential guidance once they have been carefully validated. This review discusses each of these important factors to provide a framework for understanding the complex and current challenges of managing the septic patient. Clinical trial failures and the therapeutic interventions that have proven successful are also discussed. PMID:23899564

  13. 3D face recognition based on multiple keypoint descriptors and sparse representation.

    Directory of Open Access Journals (Sweden)

    Lin Zhang

    Full Text Available Recent years have witnessed a growing interest in developing methods for 3D face recognition. However, 3D scans often suffer from the problems of missing parts, large facial expressions, and occlusions. To be useful in real-world applications, a 3D face recognition approach should be able to handle these challenges. In this paper, we propose a novel general approach to deal with the 3D face recognition problem by making use of multiple keypoint descriptors (MKD and the sparse representation-based classification (SRC. We call the proposed method 3DMKDSRC for short. Specifically, with 3DMKDSRC, each 3D face scan is represented as a set of descriptor vectors extracted from keypoints by meshSIFT. Descriptor vectors of gallery samples form the gallery dictionary. Given a probe 3D face scan, its descriptors are extracted at first and then its identity can be determined by using a multitask SRC. The proposed 3DMKDSRC approach does not require the pre-alignment between two face scans and is quite robust to the problems of missing data, occlusions and expressions. Its superiority over the other leading 3D face recognition schemes has been corroborated by extensive experiments conducted on three benchmark databases, Bosphorus, GavabDB, and FRGC2.0. The Matlab source code for 3DMKDSRC and the related evaluation results are publicly available at http://sse.tongji.edu.cn/linzhang/3dmkdsrcface/3dmkdsrc.htm.

  14. Explaining Newton's Laws of Motion: Using Student Reasoning through Representations to Develop Conceptual Understanding

    Science.gov (United States)

    Waldrip, Bruce; Prain, Vaughan; Sellings, Peter

    2013-01-01

    The development of students' reasoning and argumentation skills in school science is currently attracting strong research interest. In this paper we report on a study where we aimed to investigate student learning on the topic of motion when students, guided by their teacher, responded to a sequence of representational challenges in which their…

  15. Contemporary Multi-Modal Historical Representations and the Teaching of Disciplinary Understandings in History

    Science.gov (United States)

    Donnelly, Debra J.

    2018-01-01

    Traditional privileging of the printed text has been considerably eroded by rapid technological advancement and in Australia, as elsewhere, many History teaching programs feature an array of multi-modal historical representations. Research suggests that engagement with the visual and multi-modal constructs has the potential to enrich the pedagogy…

  16. Trafficking (in Representations: Understanding the recurring appeal of victimhood and slavery in neoliberal times

    Directory of Open Access Journals (Sweden)

    Rutvica Andrijasevic

    2016-09-01

    Full Text Available Representations of trafficking and forced labour are pervasive within media, policymaking, and humanitarian debates, discourses and interventions. The terms exploitation and trafficking are increasingly used to characterise the work that migrants do in the sex industry and other irregular employment sectors. Of late, the notion of ‘modern slavery’ is on show in campaigns aiming to raise awareness about trafficking and funds for anti-trafficking initiatives among corporations and local enterprises as well as the general public. Celebrity interventions, militant documentaries, artistic works and fiction films have all become powerful vectors of the global distribution of the trafficking and ‘modern slavery’ rhetoric. These offer simplistic solutions to complex issues without challenging the structural and causal factors of inequality. Through fictional and narrow representations of ideal victims they tend to entrench racialised narratives and conflate all sex work with trafficking, which legitimates criminalising policies and interventions exacerbating the social vulnerability of sex workers. It is because of the under-researched role of representation in the development of anti-trafficking policies and initiatives that the Anti-Trafficking Review decided to devote a thematic issue on trafficking representations.

  17. The Effect of the Use of Number Lines Representations on Student Understanding of Basic Function Concepts.

    Science.gov (United States)

    Olsen, James R.

    Researchers and educators are calling for increased use of technology and attention to function concepts in school mathematics. Students often have considerable difficulty gleaning pointwise and global information from Cartesian (R squared) representations of functions, whether they are hand- or machine-produced. Described here is an interactive…

  18. Teaching Subtraction and Multiplication with Regrouping Using the Concrete-Representational-Abstract Sequence and Strategic Instruction Model

    Science.gov (United States)

    Flores, Margaret M.; Hinton, Vanessa; Strozier, Shaunita D.

    2014-01-01

    Based on Common Core Standards (2010), mathematics interventions should emphasize conceptual understanding of numbers and operations as well as fluency. For students at risk for failure, the concrete-representational-abstract (CRA) sequence and the Strategic Instruction Model (SIM) have been shown effective in teaching computation with an emphasis…

  19. Multiple neural states of representation in short-term memory? It's a matter of attention

    Directory of Open Access Journals (Sweden)

    Joshua J Larocque

    2014-01-01

    Full Text Available Short-term memory (STM refers to the capacity-limited retention of information over a brief period of time, and working memory (WM refers to the manipulation and use of that information to guide behavior. In recent years it has become apparent that STM and WM interact and overlap with other cognitive processes, including attention (the selection of a subset of information for further processing and long-term memory (LTM – the encoding and retention of an effectively unlimited amount of information for a much longer period of time. Broadly speaking, there have been two classes of memory models: systems models, which posit distinct stores for STM and LTM (Atkinson & Shiffrin, 1968; Baddeley & Hitch, 1974; and state-based models, which posit a common store with different activation states corresponding to STM and LTM (Cowan, 1995; McElree, 1996; Oberauer, 2002. In this paper, we will focus on state-based accounts of STM. First, we will consider several theoretical models that postulate, based on considerable behavioral evidence, that information in STM can exist in multiple representational states. We will then consider how neural data from recent studies of STM can inform and constrain these theoretical models. In the process we will highlight the inferential advantage of multivariate, information-based analyses of neuroimaging data (fMRI and EEG over conventional activation-based analysis approaches (Postle, in press. We will conclude by addressing lingering questions regarding the fractionation of STM, highlighting differences between the attention to information vs. the retention of information during brief memory delays.

  20. Probabilistic images (PBIS): A concise image representation technique for multiple parameters

    Energy Technology Data Exchange (ETDEWEB)

    Wu, L.C.; Yeh, S.H.; Chen, Z.; Liu, R.S.

    1984-01-01

    Based on m parametric images (PIs) derived from a dynamic series (DS), each pixel of DS is regarded as an m-dimensional vector. Given one set of normal samples (pixels) N and another of abnormal samples A, probability density functions (pdfs) of both sets are estimated. Any unknown sample is classified into N or A by calculating the probability of its being in the abnormal set using the Bayes' theorem. Instead of estimating the multivariate pdfs, a distance ratio transformation is introduced to map the m-dimensional sample space to one dimensional Euclidean space. Consequently, the image that localizes the regional abnormalities is characterized by the probability of being abnormal. This leads to the new representation scheme of PBIs. Tc-99m HIDA study for detecting intrahepatic lithiasis (IL) was chosen as an example of constructing PBI from 3 parameters derived from DS and such a PBI was compared with those 3 PIs, namely, retention ratio image (RRI), peak time image (TNMAX) and excretion mean transit time image (EMTT). 32 normal subjects and 20 patients with proved IL were collected and analyzed. The resultant sensitivity and specificity of PBI were 97% and 98% respectively. They were superior to those of any of the 3 PIs: RRI (94/97), TMAX (86/88) and EMTT (94/97). Furthermore, the contrast of PBI was much better than that of any other image. This new image formation technique, based on multiple parameters, shows the functional abnormalities in a structural way. Its good contrast makes the interpretation easy. This technique is powerful compared to the existing parametric image method.

  1. Probabilistic images (PBIS): A concise image representation technique for multiple parameters

    International Nuclear Information System (INIS)

    Wu, L.C.; Yeh, S.H.; Chen, Z.; Liu, R.S.

    1984-01-01

    Based on m parametric images (PIs) derived from a dynamic series (DS), each pixel of DS is regarded as an m-dimensional vector. Given one set of normal samples (pixels) N and another of abnormal samples A, probability density functions (pdfs) of both sets are estimated. Any unknown sample is classified into N or A by calculating the probability of its being in the abnormal set using the Bayes' theorem. Instead of estimating the multivariate pdfs, a distance ratio transformation is introduced to map the m-dimensional sample space to one dimensional Euclidean space. Consequently, the image that localizes the regional abnormalities is characterized by the probability of being abnormal. This leads to the new representation scheme of PBIs. Tc-99m HIDA study for detecting intrahepatic lithiasis (IL) was chosen as an example of constructing PBI from 3 parameters derived from DS and such a PBI was compared with those 3 PIs, namely, retention ratio image (RRI), peak time image (TNMAX) and excretion mean transit time image (EMTT). 32 normal subjects and 20 patients with proved IL were collected and analyzed. The resultant sensitivity and specificity of PBI were 97% and 98% respectively. They were superior to those of any of the 3 PIs: RRI (94/97), TMAX (86/88) and EMTT (94/97). Furthermore, the contrast of PBI was much better than that of any other image. This new image formation technique, based on multiple parameters, shows the functional abnormalities in a structural way. Its good contrast makes the interpretation easy. This technique is powerful compared to the existing parametric image method

  2. Multi-channel EEG-based sleep stage classification with joint collaborative representation and multiple kernel learning.

    Science.gov (United States)

    Shi, Jun; Liu, Xiao; Li, Yan; Zhang, Qi; Li, Yingjie; Ying, Shihui

    2015-10-30

    Electroencephalography (EEG) based sleep staging is commonly used in clinical routine. Feature extraction and representation plays a crucial role in EEG-based automatic classification of sleep stages. Sparse representation (SR) is a state-of-the-art unsupervised feature learning method suitable for EEG feature representation. Collaborative representation (CR) is an effective data coding method used as a classifier. Here we use CR as a data representation method to learn features from the EEG signal. A joint collaboration model is established to develop a multi-view learning algorithm, and generate joint CR (JCR) codes to fuse and represent multi-channel EEG signals. A two-stage multi-view learning-based sleep staging framework is then constructed, in which JCR and joint sparse representation (JSR) algorithms first fuse and learning the feature representation from multi-channel EEG signals, respectively. Multi-view JCR and JSR features are then integrated and sleep stages recognized by a multiple kernel extreme learning machine (MK-ELM) algorithm with grid search. The proposed two-stage multi-view learning algorithm achieves superior performance for sleep staging. With a K-means clustering based dictionary, the mean classification accuracy, sensitivity and specificity are 81.10 ± 0.15%, 71.42 ± 0.66% and 94.57 ± 0.07%, respectively; while with the dictionary learned using the submodular optimization method, they are 80.29 ± 0.22%, 71.26 ± 0.78% and 94.38 ± 0.10%, respectively. The two-stage multi-view learning based sleep staging framework outperforms all other classification methods compared in this work, while JCR is superior to JSR. The proposed multi-view learning framework has the potential for sleep staging based on multi-channel or multi-modality polysomnography signals. Copyright © 2015 Elsevier B.V. All rights reserved.

  3. The effectiveness of cognitive- behavior therapy on illness representations of multiple-sclerosis and improving their emotional states

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    Farhad Hazhir

    2012-01-01

    Full Text Available Background: Illness representations (based on Leventhal's model are associated with chronic illness outcomes. It has been suggested that targeting these cognitive components improves illness outcomes. Multiple sclerosis is a common disorder between neural and immune systems that creates physical and psychological consequences. There are few pre psychological trails on these patients. The aim of this study was to determine effectiveness of cognitive-behavior therapy on altering illness representations and improving emotional states of the patients.Methods: By using a randomized controlled trial design, among 52 selected patients, 35 volunteers randomly were allocated into intervention and control groups. An extensive interventional cognitive behavior therapy based package was conducted to intervention group in 10 weekly sessions. The control group stayed in waiting list and participated in 5 group meeting sessions. (IPQR and (DASS-42 psychological scales were administered, Leven and T statistical tests were applied for dat analysis.Results: The results showed positive changes in four illness representation components of patients including illness (identity, consequences, coherence and personal control. Associated improvement occurred in depression, anxiety, stress and emotional representations.Conclusion: Mooney and Padeskey's theoretically based cognitive-behavior therapy, is effective on illness representations modification and improving emotional states of the patients. The findings are less similar to Goodman's trial on Systemic Lupus Erythematosus patients and more similar to Petrie's trail on cardiac patients.

  4. Heterogeneity of the left temporal lobe in semantic representation and control: priming multiple versus single meanings of ambiguous words.

    Science.gov (United States)

    Whitney, Carin; Jefferies, Elizabeth; Kircher, Tilo

    2011-04-01

    Semantic judgments involve both representations of meaning plus executive mechanisms that guide knowledge retrieval in a task-appropriate way. These 2 components of semantic cognition-representation and control-are commonly linked to left temporal and prefrontal cortex, respectively. This simple proposal, however, remains contentious because in most functional neuroimaging studies to date, the number of concepts being activated and the involvement of executive processes during retrieval are confounded. Using functional magnetic resonance imaging, we examined a task in which semantic representation and control demands were dissociable. Words with multiple meanings like "bank" served as targets in a double-prime paradigm, in which multiple meaning activation and maximal executive demands loaded onto different priming conditions. Anterior inferior temporal gyrus (ITG) was sensitive to the number of meanings that were retrieved, suggesting a role for this region in semantic representation, while posterior middle temporal gyrus (pMTG) and inferior frontal cortex showed greater activation in conditions that maximized executive demands. These results support a functional dissociation between left ITG and pMTG, consistent with a revised neural organization in which left prefrontal and posterior temporal areas work together to underpin aspects of semantic control.

  5. Understanding the Theory of Multiple Intelligences. Staff Workshop Handout

    Science.gov (United States)

    Early Childhood Today, 2005

    2005-01-01

    In his "Theory of Multiple Intelligences," Dr. Howard Gardner expands the concept of intelligence to include such areas as music, spatial relations, and interpersonal knowledge in addition to the traditional view of two intelligences--mathematical and linguistic. Using biological as well as cultural research, Gardner formulated a list of seven…

  6. Examining Multiple Dimensions of Word Knowledge for Content Vocabulary Understanding

    Science.gov (United States)

    Cervetti, Gina N.; Tilson, Jennifer L.; Castek, Jill; Bravo, Marco A.; Trainin, Guy

    2012-01-01

    This study traces the development of a vocabulary measure designed to assess multiple types of word knowledge. The assessment, which was administered in conjunction with a science unit about weather and the water cycle for third-and-fourth graders, included items for six knowledge types--recognition, definition, classification/example, context,…

  7. Conceptual Mis(understandings) of Fractions: From Area Models to Multiple Embodiments

    Science.gov (United States)

    Zhang, Xiaofen; Clements, M. A.; Ellerton, Nerida F.

    2015-01-01

    Area-model representations seem to have been dominant in the teaching and learning of fractions, especially in primary school mathematics curricula. In this study, we investigated 40 fifth grade children's understandings of the unit fractions, 1/2, 1/3, and 1/4, represented through a variety of different models. Analyses of pre-teaching test and…

  8. Procedures as a Representation for Data in a Computer Program for Understanding Natural Language.

    Science.gov (United States)

    Winograd, Terry

    This paper describes a system for the computer understanding of English. The system answers questions, executes commands, and accepts information in normal English dialogue. It uses semantic information and context to understand discourse and to disambiguate sentences. It combines a complete syntactic analysis of each sentence with a heuristic…

  9. Who Learns Best with Multiple Representations? Cognitive Theory Implications for Individual Differences in Multimedia Learning.

    Science.gov (United States)

    Moreno, Roxana

    This paper presents a cognitive theory of multimedia learning from which predictions on individual differences in learning are derived and tested. Elementary students learned how to add and subtract integers with an interactive multimedia game that included visual and symbolic representations of the arithmetic procedure. They learned either with…

  10. MBsums. A Mathematica package for the representation of Mellin-Barnes integrals by multiple sums

    Energy Technology Data Exchange (ETDEWEB)

    Ochman, Michal; Riemann, Tord

    2015-11-15

    Feynman integrals may be represented by the Mathematica package AMBRE and MB as multiple Mellin-Barnes integrals. With the Mathematica package MBsums we transform these Mellin-Barnes integrals into multiple sums.

  11. Developing Essential Understanding of Multiplication and Division for Teaching Mathematics in Grades 3-5

    Science.gov (United States)

    Otto, Albert; Caldwell, Janet; Hancock, Sarah Wallus; Zbiek, Rose Mary

    2011-01-01

    This book identifies and examines two big ideas and related essential understandings for teaching multiplication and division in grades 3-5. Big Idea 1 captures the notion that multiplication is usefully defined as a scalar operation. Problem situations modeled by multiplication have an element that represents the scalar and an element that…

  12. Social Representations Of Violence Against Rural Women: Unveiling Senses In Multiple Views

    Directory of Open Access Journals (Sweden)

    Marta Cocco Costa

    2014-04-01

    Full Text Available We analyze the social representations of violence against women from the perspective of city managers, professionals and health workers in rural settings of the southern half of Rio Grande do Sul. The study has a qualitative approach and adds a theoretical/methodological perspective of social representations. The data were generated by means of the associative method, question-stimulus of words and expressions emergence. The analysis of word association was performed with EVOC software, considering frequency and order of association with inducing terms. Participants recognize violence against women as gender destination that induces consent, resignation, guilt and fear, and results in naturalization and trivialization of this social phenomenon. We highlight the need to produce ruptures in established and traditional forms of health care, in the conservative and stereotypical views of violence, favoring access to friendly service and avoiding the reproduction of gender inequalities.

  13. Social Representations Of Violence Against Rural Women: Unveiling Senses In Multiple Views

    Directory of Open Access Journals (Sweden)

    Marta Cocco Costa

    Full Text Available We analyze the social representations of violence against women from the perspective of city managers, professionals and health workers in rural settings of the southern half of Rio Grande do Sul. The study has a qualitative approach and adds a theoretical/methodological perspective of social representations. The data were generated by means of the associative method, question-stimulus of words and expressions emergence. The analysis of word association was performed with EVOC software, considering frequency and order of association with inducing terms. Participants recognize violence against women as gender destination that induces consent, resignation, guilt and fear, and results in naturalization and trivialization of this social phenomenon. We highlight the need to produce ruptures in established and traditional forms of health care, in the conservative and stereotypical views of violence, favoring access to friendly service and avoiding the reproduction of gender inequalities.

  14. Pain characteristics in fibromyalgia: understanding the multiple dimensions of pain.

    Science.gov (United States)

    Plazier, Mark; Ost, Jan; Stassijns, Gaëtane; De Ridder, Dirk; Vanneste, Sven

    2015-04-01

    Fibromyalgia is a common disease with a high economic burden. The etiology of this disease remains unclear, as there are no specific abnormalities on clinical or technical examinations. Evidence suggests that central pain sensitization at the brain pain matrix might be involved. Understanding the pain characteristics of this disease is of importance both for diagnosis and treatment. The authors present their findings of pain characteristics in a Belgium population of fibromyalgia patients. Data of 65 patients (57 male and 8 female patients) were analyzed in this study (mean age 46.86, SD = +8.79). Patients filled out the following questionnaires: visual analogue scale, fibromyalgia impact questionnaire, pain-catastrophizing scale, pain vigilance and awareness questionnaire, modified fatigue impact scale, the Beck depression inventory, the short form 36 and the Dutch shortened profile of mood states. Statistical analysis was performed making use of a factor analysis and a hierarchical cluster analysis. We were able to define pain characteristics in this group of patients. The reciprocal effects of mood and fatigue on pain experience could be identified within the data, catastrophizing scores show a high correlation with overall life quality and pain experience. We have performed a cluster analysis on the fibromyalgia patients, based on the four main principal components defining the overall disease burden. Mood explained most of the variance in symptoms, followed by mental health state, fatigue, and catastrophizing. Three clusters of patients could be revealed by these components. Clusters: 1 high scores on mood disorders, pain, and decreased mental health, 2 high scores on fatigue and physical health, and 3 a mixture of these two groups. This data suggest that different subgroups of fibromyalgia patients could be identified and based on that, treatment strategies and results might be adapted.

  15. The 'subjective' risk mapping: understanding of a technical risk representation by a professional group

    International Nuclear Information System (INIS)

    Bertin, H.; Deleuze, G.

    2006-01-01

    The paper presents the application of a particular way to make risk maps, called 'subjective risk mapping'. It has been used to understand how the risk of tube rupture under pressure is understood, defined, and set in perspective with other risks in a professional group working in an industrial plant. (authors)

  16. Understanding How Reverse Engineers Make Sense of Programs from Assembly Language Representations

    Science.gov (United States)

    2012-03-01

    disagreements. If codes had weak interrater reliability (0.4 or below), the categories would be removed or changed and the data was recoded. Disagreement and re... weaknesses in software to exploit organizational dependencies and lack of understanding of low-level technologies. Better trained Air Force personnel...Technical report, Department of Computer Science, University of Auckland , 1997. 51. Conrad F., Blair J., and Tracy E. “Verbal reports are data! A theoretical

  17. Aware Computing in Spatial Language Understanding Guided by Cognitively Inspired Knowledge Representation

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    Masao Yokota

    2012-01-01

    Full Text Available Mental image directed semantic theory (MIDST has proposed an omnisensory mental image model and its description language Lmd. This language is designed to represent and compute human intuitive knowledge of space and can provide multimedia expressions with intermediate semantic descriptions in predicate logic. It is hypothesized that such knowledge and semantic descriptions are controlled by human attention toward the world and therefore subjective to each human individual. This paper describes Lmd expression of human subjective knowledge of space and its application to aware computing in cross-media operation between linguistic and pictorial expressions as spatial language understanding.

  18. Thinking processes of Filipino teachers representation of schema of some biology topics: Its effects to the students conceptual understanding

    Science.gov (United States)

    Barquilla, Manuel B.

    2018-01-01

    This study is a qualitative-quantitative research, where the main concern is to investigate Content knowledge representation of Filipino Teachers in their schema (proposition, linear ordering and imagery) of some biology topics. The five biology topics includes: Photosynthesis, Cellular Respiration, human reproductive system, Mendelian genetics and NonMendelian genetics. The study focuses on the six (6) biology teachers and a total of 222 students in their respective classes. Of the Six (6) teachers, three (3) are under the Science curriculum and three (3) under regular curriculum in both public and private schools in Iligan city and Lanao del Norte, Philippines. The study utilizes interpretative case-study method, bracketing method, and concept analysis for qualitative part. For quantitative, it uses a nonparametric statistical tool, Kendall's Tau to determine congruence of students and teachers' concept maps and paired t-test for testing the significant differences of pre-and post-instruction concept maps to determine the effects of students' conceptual understanding before and after the teacher's representation of their schema that requires the teachers' thinking processes. The data were cross-validated with two or more techniques used in the study. The data collection entailed seven (7) months immersion: one (1) month for preliminary phase for the researcher to gain teachers' and students' confidence and the succeeding six (6) months for main observation and data collection. Results indicate that the teacher utilize six methods to construct meaning of concepts, three methods of representing classification, four methods to represent relationships, seven methods to represent transformation and three methods to represent causation in planning and implementing the lessons. They often modify definitions in the textbook and express these in lingua franca to be better understood by the students. Furthermore, the teachers' analogs given to student are sometimes far

  19. STUDENT MISCONCEPTION ON REDOX TITRATION (A CHALLENGE ON THE COURSE IMPLEMENTATION THROUGH COGNITIVE DISSONANCE BASED ON THE MULTIPLE REPRESENTATIONS

    Directory of Open Access Journals (Sweden)

    H. R. Widarti

    2016-04-01

    Full Text Available The misconception is one of the obstacles in the concept mastery that needed to be minimalized. This descriptive study was conducted to find the patterns of misconceptions which have occurred on college students who participating in the redox titration course subject. Efforts to minimize misconceptions have been conducted through lectures using the multiple representations with the cognitive dissonance strategies on the 30 students who joined the Fundamentals of Analytical Chemistry course. The research instrument used in this study was 6 multiple-choice tests with reasons. In order to detect the misconception, Certainty of Response Index technique was performed. The preliminary study results showed that 34.30% of students experiencing the misconceptions on redox titration. After treatments, the misconceptions reduced to 28.17%. A misconception that cannot be eliminated was related to the concepts involving in the microscopic and symbolic appearances.

  20. A Hierarchical Approach for Measuring the Consistency of Water Areas between Multiple Representations of Tile Maps with Different Scales

    Directory of Open Access Journals (Sweden)

    Yilang Shen

    2017-08-01

    Full Text Available In geographic information systems, the reliability of querying, analysing, or reasoning results depends on the data quality. One central criterion of data quality is consistency, and identifying inconsistencies is crucial for maintaining the integrity of spatial data from multiple sources or at multiple resolutions. In traditional methods of consistency assessment, vector data are used as the primary experimental data. In this manuscript, we describe the use of a new type of raster data, tile maps, to access the consistency of information from multiscale representations of the water bodies that make up drainage systems. We describe a hierarchical methodology to determine the spatial consistency of tile-map datasets that display water areas in a raster format. Three characteristic indices, the degree of global feature consistency, the degree of local feature consistency, and the degree of overlap, are proposed to measure the consistency of multiscale representations of water areas. The perceptual hash algorithm and the scale-invariant feature transform (SIFT descriptor are applied to extract and measure the global and local features of water areas. By performing combined calculations using these three characteristic indices, the degrees of consistency of multiscale representations of water areas can be divided into five grades: exactly consistent, highly consistent, moderately consistent, less consistent, and inconsistent. For evaluation purposes, the proposed method is applied to several test areas from the Tiandi map of China. In addition, we identify key technologies that are related to the process of extracting water areas from a tile map. The accuracy of the consistency assessment method is evaluated, and our experimental results confirm that the proposed methodology is efficient and accurate.

  1. The Cognitive Estimation Task Is Nonunitary: Evidence for Multiple Magnitude Representation Mechanisms Among Normative and ADHD College Students

    Directory of Open Access Journals (Sweden)

    Sarit Ashkenazi

    2017-02-01

    Full Text Available There is a current debate on whether the cognitive system has a shared representation for all magnitudes or whether there are unique representations. To investigate this question, we used the Biber cognitive estimation task. In this task, participants were asked to provide estimates for questions such as, “How many sticks of spaghetti are in a package?” The task uses different estimation categories (e.g., time, numerical quantity, distance, and weight to look at real-life magnitude representations. Experiment 1 assessed (N = 95 a Hebrew version of the Biber Cognitive Estimation Task and found that different estimation categories had different relations, for example, weight, time, and distance shared variance, but numerical estimation did not. We suggest that numerical estimation does not require the use of measurement in units, hence, it represents a more “pure” numerical estimation. Experiment 2 found that different factors explain individual abilities in different estimation categories. For example, numerical estimation was predicted by preverbal innate quantity understanding (approximate number sense and working memory, whereas time estimations were supported by IQ. These results demonstrate that cognitive estimation is not a unified construct.

  2. Varied representation of the West Pacific pattern in multiple dynamical seasonal predictions of APCC-MME

    Science.gov (United States)

    Lee, Yun-Young

    2017-04-01

    West Pacific (WP) teleconnection pattern is one of the well-known primary modes of boreal winter low-frequency variability (LFV) resolved in 500 hPa geopotential height and its phase and amplitude strongly influence regional weather conditions including temperature and rainfall extremes [Baxter and Nigam, 2015; Hsu and Wallace, 1985; Linkin and Nigam, 2008; Mo and Livezey, 1986; Thompson and Wallace, 1998; Wallace and Gutzler, 1981]. This study primary aims to evaluate individual 11 GCMs seasonal hindcasts employed as members of multi-model ensemble (MME) produced in APEC Climate Center (APCC) in representing WP. For the extensive and comprehensive evaluation, this study applied seven verification metrics in three scopes: (a) temporal representation of observed indices, (b) spatial mode separation in the Northern Hemisphere (NH), and (c) regional mode isolated in the preset longitudinal domain. Verification results display quite large inter-model spread. Some models mimic observed index variability while others display large bias of index variability compared to climatology. Basic north-south dipole pattern is mostly well reproduced in both rotated and unrotated loading modes. However, each individual seasonal forecast model exhibits slightly different behavior (e.g. amplification/weakening, zonal and meridional shift, downstream extension and so forth) in representing spatial structure of WP. When taking all 7 metrics into account, one Europe (CMCC) model, one Oceania (POAMA) model and two North America (NASA and NCEP) models are classified as relatively good performers while PNU is classified as a matchless poor performer out of 11. Least WP representing skill of PNU is sort of consistent with the largest bias of NH total variability. This study further tries to examine winter mean biases of individual models and figure out how mean bias is linked to WP representation in model world. Model bias of winter climatology is investigated focusing on six large scale

  3. When data representation compromise data security

    DEFF Research Database (Denmark)

    Simonsen, Eivind Ortind; Dahl, Mads Ronald

    WHEN DATA REPRESENTATION COMPROMISE DATA SECURITY The workflow of transforming data into informative representations makes extensive usage of computers and software. Scientists have a conventional tradition for producing publications that include tables and graphs as data representations. These r...... the software companies having more interest in understanding and solving this type of data security issues.......WHEN DATA REPRESENTATION COMPROMISE DATA SECURITY The workflow of transforming data into informative representations makes extensive usage of computers and software. Scientists have a conventional tradition for producing publications that include tables and graphs as data representations....... These representations can be used for multiple purposes such as publications in journals, teaching and conference material. But when created, stored and distributed in a digital form there is a risk of compromising data security. Data beyond the once used specifically to create the representation can be included...

  4. An Explanation for the Use of Arrays to Promote the Understanding of Mental Strategies for Multiplication

    Science.gov (United States)

    Day, Lorraine; Hurrell, Derek

    2015-01-01

    Lorraine Day and Derek Hurrell provide a convincing argument for using arrays to promote students' understandings of mental computation strategies for multiplication. They also provide a range of different examples that illustrate the benefits of arrays in the primary classroom.

  5. A Design Study to Develop Young Children's Understanding of Multiplication and Division

    Science.gov (United States)

    Bicknell, Brenda; Young-Loveridge, Jenny; Nguyen, Nhung

    2016-01-01

    This design study investigated the use of multiplication and division problems to help 5-year-old children develop an early understanding of multiplication and division. One teacher and her class of 15 5-year-old children were involved in a collaborative partnership with the researchers. The design study was conducted over two 4-week periods in…

  6. The probabilistic image: a concise image representation technique for multiple parameters

    International Nuclear Information System (INIS)

    Wu, L.C.; Yeh, S.H.; Liu, R.S.; National Yang-Mills Medical Coll., Taipei, Taiwan); Chen, Z.

    1984-01-01

    In scintiscanning studies, an attempt has been made to use multiple parametric information to evaluate functional abnormalities in human organs, using the probabilistic domain instead of the parametric domain to present single or multiple parameters in one image. The construction of such a probabilistic image (PBI) has been illustrated from a 99 Tcsup(m)-HIDA study in 32 normal subjects and in 20 patients with intrahepatic lithiasis. The results show that this technique shows the functional abnormalities in a structural format with a good contrast and probabilistic sense. (U.K.)

  7. The representation of inflammatory signals in the brain: A model for subjective fatigue in multiple sclerosis

    NARCIS (Netherlands)

    Hanken, K.; Eling, P.A.T.M.; Hildebrandt, H.

    2014-01-01

    In multiple sclerosis (MS) patients, fatigue is rated as one of the most common and disabling symptoms. However, the pathophysiology underlying this fatigue is not yet clear. Several lines of evidence suggest that immunological factors, such as elevated levels of pro-inflammatory cytokines, may

  8. The Representation of Multiple Intelligences Types in the Top-Notch Series: A Textbook Evaluation

    Science.gov (United States)

    Razmjoo, Seyyed Ayatollah; Jozaghi, Zahra

    2010-01-01

    This study aims at evaluating Top-Notch series through a checklist devised by the researchers based on the elements of the Multiple Intelligences (MI) theory proposed by Gardner (1998). With the shift from teacher-centered classrooms to learner-centered one, more and more research is needed to be done in the realm of students' need analysis. One…

  9. Polysemy and the Taxonomic Constraint: Children's Representation of Words That Label Multiple Kinds

    Science.gov (United States)

    Srinivasan, Mahesh; Snedeker, Jesse

    2014-01-01

    How do children resolve the problem of indeterminacy when learning a new word? By one account, children adopt a "taxonomic assumption" and expect the word to denote only members of a particular taxonomic category. According to one version of this constraint, young children should represent polysemous words that label multiple kinds--for…

  10. Distinct representations of subtraction and multiplication in the neural systems for numerosity and language

    Science.gov (United States)

    Prado, Jérôme; Mutreja, Rachna; Zhang, Hongchuan; Mehta, Rucha; Desroches, Amy S.; Minas, Jennifer E.; Booth, James R.

    2010-01-01

    It has been proposed that recent cultural inventions such as symbolic arithmetic recycle evolutionary older neural mechanisms. A central assumption of this hypothesis is that the degree to which a pre-existing mechanism is recycled depends upon the degree of similarity between its initial function and the novel task. To test this assumption, we investigated whether the brain region involved in magnitude comparison in the intraparietal sulcus (IPS), localized by a numerosity comparison task, is recruited to a greater degree by arithmetic problems that involve number comparison (single-digit subtractions) than by problems that involve retrieving facts from memory (single-digit multiplications). Our results confirmed that subtractions are associated with greater activity in the IPS than multiplications, whereas multiplications elicit greater activity than subtractions in regions involved in verbal processing including the middle temporal gyrus and inferior frontal gyrus that were localized by a phonological processing task. Pattern analyses further indicated that the neural mechanisms more active for subtraction than multiplication in the IPS overlap with those involved in numerosity comparison, and that the strength of this overlap predicts inter-individual performance in the subtraction task. These findings provide novel evidence that elementary arithmetic relies on the co-option of evolutionary older neural circuits. PMID:21246667

  11. Deepening Students' Understanding of Multiplication and Division by Exploring Divisibility by Nine

    Science.gov (United States)

    Young-Loveridge, Jenny; Mills, Judith

    2012-01-01

    This article explores how a focus on understanding divisibility rules can be used to help deepen students' understanding of multiplication and division with whole numbers. It is based on research with seven Year 7-8 teachers who were observed teaching a group of students a rule for divisibility by nine. As part of the lesson, students were shown a…

  12. From Sailing Ships to Subtraction Symbols: Multiple Representations to Support Abstraction

    Science.gov (United States)

    Jao, Limin

    2013-01-01

    Teachers are tasked with supporting students' learning of abstract mathematical concepts. Students can represent their mathematical understanding in a variety of modes, for example: manipulatives, pictures, diagrams, spoken languages, and written symbols. Although most students easily pick up rudimentary knowledge through the use of concrete…

  13. Multiple Representations in Modeling Strategies for the Development of Systems Thinking in Biology Education

    NARCIS (Netherlands)

    Verhoeff, R.P.|info:eu-repo/dai/nl/165575581; Boersma, K.T.|info:eu-repo/dai/nl/073043141; Waarlo, A.J.|info:eu-repo/dai/nl/074372246

    2013-01-01

    For biological researchers, systems thinking is a basic conceptual framework, and many educationalists consider systems thinking as a metacognitive skill that enables students to understand and cope with the new scientific advancements that reach our society. With this in mind, we investigated the

  14. Improving the security of multiple passwords through a greater understanding of the human memory

    OpenAIRE

    Woods, Naomi

    2016-01-01

    Multiple passwords are an increasing security issue that will only get worse with time. One of the major factors that compromise multiple passwords is users’ memory, and the behaviors they adopt to compensate for its failures. Through studying memory elements that influence users’ password memorability, we may increase our understanding of the user and therefore make proposals to increase the security of the password authentication mechanism. This dissertation examines...

  15. Social Identity Mapping: A procedure for visual representation and assessment of subjective multiple group memberships.

    Science.gov (United States)

    Cruwys, Tegan; Steffens, Niklas K; Haslam, S Alexander; Haslam, Catherine; Jetten, Jolanda; Dingle, Genevieve A

    2016-12-01

    In this research, we introduce Social Identity Mapping (SIM) as a method for visually representing and assessing a person's subjective network of group memberships. To provide evidence of its utility, we report validating data from three studies (two longitudinal), involving student, community, and clinical samples, together comprising over 400 participants. Results indicate that SIM is easy to use, internally consistent, with good convergent and discriminant validity. Each study also illustrates the ways that SIM can be used to address a range of novel research questions. Study 1 shows that multiple positive group memberships are a particularly powerful predictor of well-being. Study 2 shows that social support is primarily given and received within social groups and that only in-group support is beneficial for well-being. Study 3 shows that improved mental health following a social group intervention is attributable to an increase in group compatibility. In this way, the studies demonstrate the capacity for SIM to make a contribution both to the development of social-psychological theory and to its practical application. © 2016 The British Psychological Society.

  16. Social Media Representation of Chronic Cerebrospinal Venous Insufficiency Intervention for Multiple Sclerosis.

    Science.gov (United States)

    Ghahari, Setareh; Forwell, Susan J

    2016-01-01

    We conducted a rigorous review of videos related to multiple sclerosis (MS) and chronic cerebrospinal venous insufficiency (CCSVI) treatment posted by people with MS on one social media website (YouTube) that describe symptoms before and after the surgical procedure, as well as videos presented by health-care professionals (HCPs). All relevant videos posted from December 2009 to July 2011 were downloaded, viewed, and systematically organized. Categorical data were classified, and dominant messages were gleaned. A total of 1789 videos were extracted. A total of 621 videos by people with MS and 238 by HCPs were included. Eighty-six percent of people with MS anecdotally reported experiencing some improvement in at least one symptom. The most common message was that "CCSVI is not a miracle but worth trying." Most HCPs posting videos recommended the procedure but called for continued research. Social media are conveying an anecdotal favorable message about CCSVI treatment for MS. The relative absence of videos offering a negative or more balanced perspective is a concern. Social persuasion through these videos creates a strong positive impression of CCSVI treatment, but the videos do not acknowledge the lack of supporting scientific evidence and the possible role of the placebo effect. Given the strong influence of social media on health-care decision making, researchers and clinicians should actively use social media to reach out to people with MS and describe the state of the evidence for MS treatments, both positive and negative.

  17. Six-moment representation of multiple aerosol populations in a sub-hemispheric chemical transformation model

    Science.gov (United States)

    Wright, D. L.; McGraw, R.; Benkovitz, C. M.; Schwartz, S. E.

    2000-04-01

    This letter describes the first application of the Quadrature Method of Moments (QMOM) [McGraw, 1997] in a 3-D chemical transformation and transport model. The QMOM simultaneously tracks an arbitrary (even) number of moments of a particle size distribution directly in space and time without the need for explicitly representing the distribution itself. The host 3-D model, the Global Chemistry Model driven by Observation-derived meteorological data (GChM-O), has been previously described [Benkovitz et al., 1994]. The present implementation evolves the six lowest-order radial moments for each of several externally-mixed aerosol populations. From these moments we report modeled geographic distributions of several aerosol properties, including a shortwave radiative forcing obtained using the Multiple Isomomental Distribution Aerosol Surrogate (MIDAS) technique [Wright, 2000]. These results demonstrate the capabilities of these moment-based techniques to simultaneously represent aerosol nucleation, condensation, coagulation, dry deposition, wet removal, cloud activation, and transport processes in a large scale model, and to yield aerosol optical properties and radiative influence from the modeled aerosol.

  18. Effects of the 5E Instructional Model Incorporated with Multiple Levels of Representations on Thai Students with Different Levels of Cognitive Development

    Science.gov (United States)

    Wichaidit, Patcharee Rompayom; Wichaidit, Sittichai

    2016-01-01

    Learning chemistry may be difficult for students for several reasons, such as the abstract nature of many chemistry concepts and the fact that students may view chemistry as irrelevant to their everyday lives. Teaching chemistry in familiar contexts and the use of multiple representations are seen as effective approaches for enhancing students'…

  19. Multiple Sclerosis in the Contemporary Age: Understanding the Millennial Patient with Multiple Sclerosis to Create Next-Generation Care.

    Science.gov (United States)

    Hansen, Madison R; Okuda, Darin T

    2018-02-01

    The average age of onset of multiple sclerosis (MS) is between 20 and 40 years of age. Therefore, most new patients diagnosed with MS within the next 10 to 15 years will be from the millennial generation, representing those born between 1982 and 2000. Certain preferences and trends of this contemporary generation will present new challenges to the MS physician and effective MS care. By first understanding these challenges, relevant and successful solutions can be created to craft a system of care that best benefits the millennial patient with MS. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. Increasing the understanding of chemical concepts: The effectiveness of multiple exposures

    Science.gov (United States)

    Bius, Janet H.

    Chemistry is difficult because it has multilevels of knowledge with each level presenting challenges in vocabulary, abstract thinking, and symbolic language. Students have to be able to transfer between levels to understand the concepts and the theoretical models of chemistry. The cognitive theories of constructivism and cognitive-load theory are used to explain the difficulties novice learners have with the subject of chemistry and methods to increase success for students. The relationship between external representations, misconceptions and topics on the success of students are addressed. If students do not know the formalisms associated with chemical diagrams and graphs, the representations will decrease student success. Misconceptions can be formed when new information is interpreted based on pre-existing knowledge that is faulty. Topics with large amount of interacting elements that must be processed simultaneously are considered difficult to understand. New variables were created to measure the number of times a student is exposed to a chemical concept. Each variable was coded according to topic and learning environment, which are the lecture and laboratory components of the course, homework assignments and textbook examples. The exposure variables are used to measure the success rate of students on similar exam questions. Question difficulty scales were adapted for this project from those found in the chemical education literature. The exposure variables were tested on each level of the difficulty scales to determine their effect at decreasing the cognitive demand of these questions. The subjects of this study were freshmen science majors at a large Midwest university. The effects of the difficulty scales and exposure variables were measured for those students whose exam scores were in the upper one-fourth percentile, for students whose test scores were in the middle one-half percentile, and the lower one-fourth percentile are those students that scored the

  1. An efficient approach to understanding and predicting the effects of multiple task characteristics on performance.

    Science.gov (United States)

    Richardson, Miles

    2017-04-01

    In ergonomics there is often a need to identify and predict the separate effects of multiple factors on performance. A cost-effective fractional factorial approach to understanding the relationship between task characteristics and task performance is presented. The method has been shown to provide sufficient independent variability to reveal and predict the effects of task characteristics on performance in two domains. The five steps outlined are: selection of performance measure, task characteristic identification, task design for user trials, data collection, regression model development and task characteristic analysis. The approach can be used for furthering knowledge of task performance, theoretical understanding, experimental control and prediction of task performance. Practitioner Summary: A cost-effective method to identify and predict the separate effects of multiple factors on performance is presented. The five steps allow a better understanding of task factors during the design process.

  2. Recent advances in understanding multiple myeloma [version 1; referees: 4 approved

    Directory of Open Access Journals (Sweden)

    Binod Dhakal

    2016-08-01

    Full Text Available There have been major recent advancements in the understanding and management of multiple myeloma. Diagnostic criteria have been revised and former ultra-high-risk smoldering multiple myeloma is now considered multiple myeloma in need of treatment. Understanding clonal progression, evolution, and tides not only has helped elucidate the disease behavior but might help expand therapeutic choices in order to select appropriate treatment for patients. Unprecedented response rates with modern triplet induction therapies containing proteasome inhibitor and immunomodulators have made this approach standard for initial treatment. The US Food and Drug Administration approved four new drugs (two targeted antibodies and two oral agents in 2015 in relapsed/refractory multiple myeloma and these drugs along with the other already-available drugs have now increased the choices of regimens. Even drugs without single-agent activity, such as panobinostat and elotuzumab, have an important role, especially in the proteasome inhibitor refractory setting. Recent studies done in the context of novel agent induction suggest that high-dose therapy followed by autologous transplant continues to improve response rates and progression-free survival, thus underscoring their role in transplant-eligible patients. Evolving paradigms in the treatment of multiple myeloma include newer promising immune approaches, such as adoptive cellular therapies, vaccines, or antibody-based immune manipulations. Though multiple myeloma is still considered incurable, it is clear that with the improved understanding of disease biology and clonal architecture of relapse combined with the availability of multi-targeted approaches, we are ever closer to a lasting cure or transformation into indolent and long-lasting disease courses or both.

  3. Teaching Transnationalism in the Caribbean: Toward an Understanding of Representation and Neo-Colonialism in Human Geography. Symposium

    Science.gov (United States)

    Mains, Susan P.

    2004-01-01

    Undergraduate geography courses provide a significant entry way into representing and challenging dominant images of places and identities. Teaching geography in the Caribbean raises significant issues in terms of providing materials that explore representations of places and topics that are grounded in the region, while also moving beyond…

  4. Understanding multiple levels of norms about teen pregnancy and their relationships to teens’ sexual behaviors

    OpenAIRE

    Mollborn, Stefanie; Domingue, Benjamin W.; Boardman, Jason D.

    2014-01-01

    Researchers seeking to understand teen sexual behaviors often turn to age norms, but they are difficult to measure quantitatively. Previous work has usually inferred norms from behavioral patterns or measured group-level norms at the individual level, ignoring multiple reference groups. Capitalizing on the multilevel design of the Add Health survey, we measure teen pregnancy norms perceived by teenagers, as well as average norms at the school and peer network levels. School norms predict boys...

  5. The Representation of Inflammatory Signals in the Brain – A Model for Subjective Fatigue in Multiple Sclerosis

    Science.gov (United States)

    Hanken, Katrin; Eling, Paul; Hildebrandt, Helmut

    2014-01-01

    In multiple sclerosis (MS) patients, fatigue is rated as one of the most common and disabling symptoms. However, the pathophysiology underlying this fatigue is not yet clear. Several lines of evidence suggest that immunological factors, such as elevated levels of pro-inflammatory cytokines, may contribute to subjective fatigue in MS patients. Pro-inflammatory cytokines represent primary mediators of immune-to-brain-communication, modulating changes in the neurophysiology of the central nervous system. Recently, we proposed a model arguing that fatigue in MS patients is a subjective feeling, which is related to inflammation. Moreover, it implies that fatigue can be measured behaviorally only by applying specific cognitive tasks related to alertness and vigilance. In the present review, we focus on the subjective feeling of MS-related fatigue. We examine the hypothesis that the subjective feeling of MS-related fatigue may be a variant of inflammation-induced sickness behavior, resulting from cytokine-mediated activity changes within brain areas involved in interoception and homeostasis including the insula, the anterior cingulate, and the hypothalamus. We first present studies demonstrating a relationship between pro-inflammatory cytokines and subjective fatigue in healthy individuals, in people with inflammatory disorders, and particularly in MS patients. Subsequently, we discuss studies analyzing the impact of anti-inflammatory treatment on fatigue. In the next part of this review, we present studies on the transmission and neural representation of inflammatory signals, with a special focus on possible neural concomitants of inflammation-induced fatigue. We also present two of our studies on the relationship between local gray and white matter atrophy and fatigue in MS patients. Finally, we discuss some implications of our findings and future perspectives. PMID:25566171

  6. The representation of inflammatory signals in the brain – a model for subjective fatigue in multiple sclerosis

    Directory of Open Access Journals (Sweden)

    Katrin eHanken

    2014-12-01

    Full Text Available In multiple sclerosis (MS patients, fatigue is rated as one of the most common and disabling symptoms. However, the pathophysiology underlying this fatigue is not yet clear. Several lines of evidence suggest that immunological factors, such as elevated levels of proinflammatory cytokines, may contribute to subjective fatigue in MS patients. Proinflammatory cytokines represent primary mediators of immune-to-brain-communication, modulating changes in the neurophysiology of the central nervous system. Recently, we proposed a model arguing that fatigue in MS patients is a subjective feeling which is related to inflammation. Moreover, it implies that fatigue can be measured behaviorally only by applying specific cognitive tasks related to alertness and vigilance. In the present review we focus on the subjective feeling of MS-related fatigue. We examine the hypothesis that the subjective feeling of MS-related fatigue may be a variant of inflammation-induced sickness behavior, resulting from cytokine-mediated activity changes within brain areas involved in interoception and homeostasis including the insula, the anterior cingulate and the hypothalamus. We first present studies demonstrating a relationship between proinflammatory cytokines and subjective fatigue in healthy individuals, in people with inflammatory disorders, and particularly in MS patients. Subsequently, we discuss studies analyzing the impact of anti-inflammatory treatment on fatigue. In the next part of this review we present studies on the transmission and neural representation of inflammatory signals, with a special focus on possible neural concomitants of inflammation-induced fatigue. We also present two of our studies on the relationship between local gray and white matter atrophy and fatigue in MS patients. Finally, we discuss some implications of our findings and future perspectives.

  7. Understanding representations of the roles of teachers and students of english as a foreign language in different contexts in the light of transitivity analysis

    Directory of Open Access Journals (Sweden)

    Solange Teresinha Ricardo de Castro

    2011-07-01

    Full Text Available This paper examines the contributions of transitivity analysis to the comprehension of how individuals from both the educational and the professional contexts view the roles of teachers and students in the process of EFL learning and teaching. Representations are the meanings which are socio-historically constructed in the linguistic activity of the different practical activities in which individuals participate in the social formations they belong to. Data are from four research corpora. Participants were from: a basic education school, an undergraduate EFL teacher education course, the HR department of a company and an undergraduate hotel management and administration course. Participants of processes, processes and circumstances were examined. Results suggest transitivity analysis is a powerful instrument to understand representations of learning and teaching in relation to their contexts.

  8. Applying mass spectrometry based proteomic technology to advance the understanding of multiple myeloma

    Directory of Open Access Journals (Sweden)

    Evans Ken

    2010-04-01

    Full Text Available Abstract Multiple myeloma (MM is the second most common hematological malignancy in adults. It is characterized by clonal proliferation of terminally differentiated B lymphocytes and over-production of monoclonal immunoglobulins. Recurrent genomic aberrations have been identified to contribute to the aggressiveness of this cancer. Despite a wealth of knowledge describing the molecular biology of MM as well as significant advances in therapeutics, this disease remains fatal. The identification of biomarkers, especially through the use of mass spectrometry, however, holds great promise to increasing our understanding of this disease. In particular, novel biomarkers will help in the diagnosis, prognosis and therapeutic stratification of MM. To date, results from mass spectrometry studies of MM have provided valuable information with regards to MM diagnosis and response to therapy. In addition, mass spectrometry was employed to study relevant signaling pathways activated in MM. This review will focus on how mass spectrometry has been applied to increase our understanding of MM.

  9. Acquiring Knowledge in Learning Concepts from Electrical Circuits: The Use of Multiple Representations in Technology-Based Learning Environments

    Directory of Open Access Journals (Sweden)

    Abdeljalil Métioui

    2012-04-01

    Full Text Available The constructivists approach on the conception of relative software of modelling to training and teaching of the concepts of current and voltage requires appraisal of several disciplinary fields in order to provide to the learners a training adapted to their representations. Thus, this approach requires the researchers to have adequate knowledge or skills in data processing, didactics and science content. In this regard, several researches underline that the acquisition of basic concepts that span a field of a given knowledge, must take into account the student and the scientific representations. The present research appears in this perspective, and aims to present the interactive computer environments that take into account the students (secondary and college and scientific representations related to simple electric circuits. These computer environments will help the students to analyze the functions of the electric circuits adequately.

  10. Multiple domains of parental secure base support during childhood and adolescence contribute to adolescents' representations of attachment as a secure base script.

    Science.gov (United States)

    Vaughn, Brian E; Waters, Theodore E A; Steele, Ryan D; Roisman, Glenn I; Bost, Kelly K; Truitt, Warren; Waters, Harriet S; Booth-Laforce, Cathryn

    2016-08-01

    Although attachment theory claims that early attachment representations reflecting the quality of the child's "lived experiences" are maintained across developmental transitions, evidence that has emerged over the last decade suggests that the association between early relationship quality and adolescents' attachment representations is fairly modest in magnitude. We used aspects of parenting beyond sensitivity over childhood and adolescence and early security to predict adolescents' scripted attachment representations. At age 18 years, 673 participants from the NICHD Study of Early Child Care and Youth Development completed the Attachment Script Assessment from which we derived an assessment of secure base script knowledge. Measures of secure base support from childhood through age 15 years (e.g., parental monitoring of child activity, father presence in the home) were selected as predictors and accounted for an additional 8% of the variance in secure base script knowledge scores above and beyond direct observations of sensitivity and early attachment status alone, suggesting that adolescents' scripted attachment representations reflect multiple domains of parenting. Cognitive and demographic variables also significantly increased predicted variance in secure base script knowledge by 2% each.

  11. Understanding disease processes in multiple sclerosis through magnetic resonance imaging studies in animal models

    Directory of Open Access Journals (Sweden)

    Nabeela Nathoo

    2014-01-01

    Full Text Available There are exciting new advances in multiple sclerosis (MS resulting in a growing understanding of both the complexity of the disorder and the relative involvement of grey matter, white matter and inflammation. Increasing need for preclinical imaging is anticipated, as animal models provide insights into the pathophysiology of the disease. Magnetic resonance (MR is the key imaging tool used to diagnose and to monitor disease progression in MS, and thus will be a cornerstone for future research. Although gadolinium-enhancing and T2 lesions on MRI have been useful for detecting MS pathology, they are not correlative of disability. Therefore, new MRI methods are needed. Such methods require validation in animal models. The increasing necessity for MRI of animal models makes it critical and timely to understand what research has been conducted in this area and what potential there is for use of MRI in preclinical models of MS. Here, we provide a review of MRI and magnetic resonance spectroscopy (MRS studies that have been carried out in animal models of MS that focus on pathology. We compare the MRI phenotypes of animals and patients and provide advice on how best to use animal MR studies to increase our understanding of the linkages between MR and pathology in patients. This review describes how MRI studies of animal models have been, and will continue to be, used in the ongoing effort to understand MS.

  12. An introduction to quasigroups and their representations

    CERN Document Server

    Smith, Jonathan D H

    2006-01-01

    Collecting results scattered throughout the literature into one source, An Introduction to Quasigroups and Their Representations shows how representation theories for groups are capable of extending to general quasigroups and illustrates the added depth and richness that result from this extension.To fully understand representation theory, the first three chapters provide a foundation in the theory of quasigroups and loops, covering special classes, the combinatorial multiplication group, universal stabilizers, and quasigroup analogues of abelian groups. Subsequent chapters deal with the three main branches of representation theory-permutation representations of quasigroups, combinatorial character theory, and quasigroup module theory. Each chapter includes exercises and examples to demonstrate how the theories discussed relate to practical applications. The book concludes with appendices that summarize some essential topics from category theory, universal algebra, and coalgebras.Long overshadowed by general ...

  13. Analysis of Peer Learning Behaviors Using Multiple Representations in Virtual Reality and Their Impacts on Geometry Problem Solving

    Science.gov (United States)

    Hwang, Wu-Yuin; Hu, Shih-Shin

    2013-01-01

    Learning geometry emphasizes the importance of exploring different representations such as virtual manipulatives, written math formulas, and verbal explanations, which help students build math concepts and develop critical thinking. Besides helping individuals construct math knowledge, peer interaction also plays a crucial role in promoting an…

  14. Predicting siRNA efficacy based on multiple selective siRNA representations and their combination at score level

    Science.gov (United States)

    He, Fei; Han, Ye; Gong, Jianting; Song, Jiazhi; Wang, Han; Li, Yanwen

    2017-03-01

    Small interfering RNAs (siRNAs) may induce to targeted gene knockdown, and the gene silencing effectiveness relies on the efficacy of the siRNA. Therefore, the task of this paper is to construct an effective siRNA prediction method. In our work, we try to describe siRNA from both quantitative and qualitative aspects. For quantitative analyses, we form four groups of effective features, including nucleotide frequencies, thermodynamic stability profile, thermodynamic of siRNA-mRNA interaction, and mRNA related features, as a new mixed representation, in which thermodynamic of siRNA-mRNA interaction is introduced to siRNA efficacy prediction for the first time to our best knowledge. And then an F-score based feature selection is employed to investigate the contribution of each feature and remove the weak relevant features. Meanwhile, we encode the siRNA sequence and existed empirical design rules as a qualitative siRNA representation. These two kinds of siRNA representations are combined to predict siRNA efficacy by supported Vector Regression (SVR) at score level. The experimental results indicate that our method may select the features with powerful discriminative ability and make the two kinds of siRNA representations work at full capacity. The prediction results also demonstrate that our method can outperform other popular siRNA efficacy prediction algorithms.

  15. Multiple intelligences and alternative teaching strategies: The effects on student academic achievement, conceptual understanding, and attitude

    Science.gov (United States)

    Baragona, Michelle

    The purpose of this study was to investigate the interactions between multiple intelligence strengths and alternative teaching methods on student academic achievement, conceptual understanding and attitudes. The design was a quasi-experimental study, in which students enrolled in Principles of Anatomy and Physiology, a developmental biology course, received lecture only, problem-based learning with lecture, or peer teaching with lecture. These students completed the Multiple Intelligence Inventory to determine their intelligence strengths, the Students' Motivation Toward Science Learning questionnaire to determine student attitudes towards learning in science, multiple choice tests to determine academic achievement, and open-ended questions to determine conceptual understanding. Effects of intelligence types and teaching methods on academic achievement and conceptual understanding were determined statistically by repeated measures ANOVAs. No significance occurred in academic achievement scores due to lab group or due to teaching method used; however, significant interactions between group and teaching method did occur in students with strengths in logical-mathematical, interpersonal, kinesthetic, and intrapersonal intelligences. Post-hoc analysis using Tukey HSD tests revealed students with strengths in logical-mathematical intelligence and enrolled in Group Three scored significantly higher when taught by problem-based learning (PBL) as compared to peer teaching (PT). No significance occurred in conceptual understanding scores due to lab group or due to teaching method used; however, significant interactions between group and teaching method did occur in students with strengths in musical, kinesthetic, intrapersonal, and spatial intelligences. Post-hoc analysis using Tukey HSD tests revealed students with strengths in logical-mathematical intelligence and enrolled in Group Three scored significantly higher when taught by lecture as compared to PBL. Students with

  16. What we can't see? Understanding the representations and meanings of UAI, barebacking, and semen exchange in gay male pornography.

    Science.gov (United States)

    Mowlabocus, Sharif; Harbottle, Justin; Witzel, Charlie

    2014-01-01

    Since the late 1990s, the use of condoms within gay male pornography has been on the wane. Moving from a niche category into more mainstream forms of commercial pornography, unprotected anal sex has become a dominant theme within this sphere of gay male sexual representation. However, while the definition of what constitutes bareback pornography may at first sight appear unproblematic, this article argues that meanings and understandings of unprotected anal intercourse (UAI) are not constant across all genres of gay male pornography. Using textual analysis and focus group methods, the authors demonstrate how subcultural understandings of UAI are dependent on a variety of textual factors. These include the age, body type, and racial identities of the performers; the setting, context, and mise-en-scène of the pornographic scene; and the deployment of power relations between the insertive and receptive partners. The article concludes by suggesting that the recognition of the diverse representations of "barebacking" found in contemporary gay male pornography should influence the ways in which health promotion strategies address discussions of UAI and bareback pornography.

  17. Developing Seventh Grade Students' Understanding of Complex Environmental Problems with Systems Tools and Representations: a Quasi-experimental Study

    Science.gov (United States)

    Doganca Kucuk, Zerrin; Saysel, Ali Kerem

    2017-03-01

    A systems-based classroom intervention on environmental education was designed for seventh grade students; the results were evaluated to see its impact on the development of systems thinking skills and standard science achievement and whether the systems approach is a more effective way to teach environmental issues that are dynamic and complex. A quasi-experimental methodology was used to compare performances of the participants in various dimensions, including systems thinking skills, competence in dynamic environmental problem solving and success in science achievement tests. The same pre-, post- and delayed tests were used with both the comparison and experimental groups in the same public middle school in Istanbul. Classroom activities designed for the comparison group (N = 20) followed the directives of the Science and Technology Curriculum, while the experimental group (N = 22) covered the same subject matter through activities benefiting from systems tools and representations such as behaviour over time graphs, causal loop diagrams, stock-flow structures and hands-on dynamic modelling. After a one-month systems-based instruction, the experimental group demonstrated significantly better systems thinking and dynamic environmental problem solving skills. Achievement in dynamic problem solving was found to be relatively stable over time. However, standard science achievement did not improve at all. This paper focuses on the quantitative analysis of the results, the weaknesses of the curriculum and educational implications.

  18. Comprehensive Phenotyping in Multiple Sclerosis: Discovery Based Proteomics and the Current Understanding of Putative Biomarkers

    Directory of Open Access Journals (Sweden)

    Kevin C. O’Connor

    2006-01-01

    Full Text Available Currently, there is no single test for multiple sclerosis (MS. Diagnosis is confirmed through clinical evaluation, abnormalities revealed by magnetic resonance imaging (MRI, and analysis of cerebrospinal fluid (CSF chemistry. The early and accurate diagnosis of the disease, monitoring of progression, and gauging of therapeutic intervention are important but elusive elements of patient care. Moreover, a deeper understanding of the disease pathology is needed, including discovery of accurate biomarkers for MS. Herein we review putative biomarkers of MS relating to neurodegeneration and contributions to neuropathology, with particular focus on autoimmunity. In addition, novel assessments of biomarkers not driven by hypotheses are discussed, featuring our application of advanced proteomics and metabolomics for comprehensive phenotyping of CSF and blood. This strategy allows comparison of component expression levels in CSF and serum between MS and control groups. Examination of these preliminary data suggests that several CSF proteins in MS are differentially expressed, and thus, represent putative biomarkers deserving of further evaluation.

  19. The role of NIGMS P50 sponsored team science in our understanding of multiple organ failure.

    Science.gov (United States)

    Moore, Frederick A; Moore, Ernest E; Billiar, Timothy R; Vodovotz, Yoram; Banerjee, Anirban; Moldawer, Lyle L

    2017-09-01

    The history of the National Institute of General Medical Sciences (NIGMS) Research Centers in Peri-operative Sciences (RCIPS) is the history of clinical, translational, and basic science research into the etiology and treatment of posttraumatic multiple organ failure (MOF). Born out of the activism of trauma and burn surgeons after the Viet Nam War, the P50 trauma research centers have been a nidus of research advances in the field and the training of future academic physician-scientists in the fields of trauma, burns, sepsis, and critical illness. For over 40 years, research conducted under the aegis of this funding program has led to numerous contributions at both the bedside and at the bench. In fact, it has been this requirement for team science with a clinician-scientist working closely with basic scientists from multiple disciplines that has led the RCIPS to its unrivaled success in the field. This review will briefly highlight some of the major accomplishments of the RCIPS program since its inception, how they have both led and evolved as the field moved steadily forward, and how they are responsible for much of our current understanding of the etiology and pathology of MOF. This review is not intended to be all encompassing nor a historical reference. Rather, it serves as recognition to the foresight and support of many past and present individuals at the NIGMS and at academic institutions who have understood the cost of critical illness and MOF to the individual and to society.

  20. Understanding multiple levels of norms about teen pregnancy and their relationships to teens’ sexual behaviors

    Science.gov (United States)

    Mollborn, Stefanie; Domingue, Benjamin W.; Boardman, Jason D.

    2014-01-01

    Researchers seeking to understand teen sexual behaviors often turn to age norms, but they are difficult to measure quantitatively. Previous work has usually inferred norms from behavioral patterns or measured group-level norms at the individual level, ignoring multiple reference groups. Capitalizing on the multilevel design of the Add Health survey, we measure teen pregnancy norms perceived by teenagers, as well as average norms at the school and peer network levels. School norms predict boys’ perceived norms, while peer network norms predict girls’ perceived norms. Peer network and individually perceived norms against teen pregnancy independently and negatively predict teens’ likelihood of sexual intercourse. Perceived norms against pregnancy predict increased likelihood of contraception among sexually experienced girls, but sexually experienced boys’ contraceptive behavior is more complicated: When both the boy and his peers or school have stronger norms against teen pregnancy he is more likely to contracept, and in the absence of school or peer norms against pregnancy, boys who are embarrassed are less likely to contracept. We conclude that: (1) patterns of behavior cannot adequately operationalize teen pregnancy norms, (2) norms are not simply linked to behaviors through individual perceptions, and (3) norms at different levels can operate independently of each other, interactively, or in opposition. This evidence creates space for conceptualizations of agency, conflict, and change that can lead to progress in understanding age norms and sexual behaviors. PMID:25104920

  1. Understanding multiple levels of norms about teen pregnancy and their relationships to teens' sexual behaviors.

    Science.gov (United States)

    Mollborn, Stefanie; Domingue, Benjamin W; Boardman, Jason D

    2014-06-01

    Researchers seeking to understand teen sexual behaviors often turn to age norms, but they are difficult to measure quantitatively. Previous work has usually inferred norms from behavioral patterns or measured group-level norms at the individual level, ignoring multiple reference groups. Capitalizing on the multilevel design of the Add Health survey, we measure teen pregnancy norms perceived by teenagers, as well as average norms at the school and peer network levels. School norms predict boys' perceived norms, while peer network norms predict girls' perceived norms. Peer network and individually perceived norms against teen pregnancy independently and negatively predict teens' likelihood of sexual intercourse. Perceived norms against pregnancy predict increased likelihood of contraception among sexually experienced girls, but sexually experienced boys' contraceptive behavior is more complicated: When both the boy and his peers or school have stronger norms against teen pregnancy he is more likely to contracept, and in the absence of school or peer norms against pregnancy, boys who are embarrassed are less likely to contracept. We conclude that: (1) patterns of behavior cannot adequately operationalize teen pregnancy norms, (2) norms are not simply linked to behaviors through individual perceptions, and (3) norms at different levels can operate independently of each other, interactively, or in opposition. This evidence creates space for conceptualizations of agency, conflict, and change that can lead to progress in understanding age norms and sexual behaviors.

  2. Assessment of Matrix Multiplication Learning with a Rule-Based Analytical Model--"A Bayesian Network Representation"

    Science.gov (United States)

    Zhang, Zhidong

    2016-01-01

    This study explored an alternative assessment procedure to examine learning trajectories of matrix multiplication. It took rule-based analytical and cognitive task analysis methods specifically to break down operation rules for a given matrix multiplication. Based on the analysis results, a hierarchical Bayesian network, an assessment model,…

  3. Understanding the role of representations of human-leopard conflict in Mumbai through media-content analysis.

    Science.gov (United States)

    Bhatia, Saloni; Athreya, Vidya; Grenyer, Richard; MacDonald, David W

    2013-06-01

    Attempts to minimize the effects of human-wildlife conflict (HWC) on conservation goals require an understanding of the mechanisms by which such conflicts are caused and sustained. This necessitates looking beyond the natural sciences to the human dimensions of wildlife management. Public dissemination of information regarding HWC occurs largely through the mass media. We conducted a content analysis of print media articles on human-leopard conflict in Mumbai, India. We sought to understand the framing of HWC and the changes in media coverage over a 10-year period (2001-2011) during which a large number of attacks on people prior to 2005 were followed by a program of trapping and relocation. After 2005, when there was a decrease in the level of conflict, the tone of English-language media reports changed. The perpetrator framing was over 5 times more likely before 2005, whereas a neutral framing was twice as likely after 2005. English-language and non-English-language print media differed significantly in their framing of HWC and in the kinds of solutions advocated. Our results also suggest the print mass media in Mumbai could be an influential conduit for content that diminishes HWC. These media outlets seem attentive to human-leopard conflict, capable of correcting erroneous perceptions and facilitating mitigation and effective management. We believe better contact and mutual understanding between conservation professionals and the mass media could be an important component of managing HWC. We further suggest that in such interactions conservation professionals need to be aware of cultural and linguistic differences in reporting within the country. © 2013 Society for Conservation Biology.

  4. Understanding Tremor in Multiple Sclerosis: Prevalence, Pathological Anatomy, and Pharmacological and Surgical Approaches to Treatment

    Directory of Open Access Journals (Sweden)

    Andrés Labiano-Fontcuberta

    2012-09-01

    Full Text Available Background: Given that tremor is one of the most prevalent and disabling features of multiple sclerosis (MS, we will review the most significant milestones in tremor in this disease in recent years, focusing on prevalence, clinical features, anatomical basis, and treatment.Methods: Data for this review were identified by searching MEDLINE with the search terms “multiple sclerosis” and “tremor”. References were also identified from relevant articles published between January 1966 and May 2012.Results: The predominant type of MS tremor is a large-amplitude, postural, and kinetic tremor, which most commonly affects the arms, although tremor can also involve head, neck, vocal cords, and trunk. Involvement of the tongue, jaw, or palate has not been reported. Although the anatomical basis underlying tremor in MS is poorly understood, the link between the cerebellum and the MS-related tremor is supported by clinical and experimental studies. Currently available medication is often unsuccessful in most cases. Surgical treatment can be a satisfactory alternative to treat severe and disabling tremor.Discussion: Tremor in MS patients could be considered as an advanced consequence of the disease and its presence suggests a more aggressive course. MS tremor can be severe and very disabling for a small group of patients. Treatment of MS tremor remains a great challenge. Recent studies suggest that dissociating tremor from cerebellar dysfunction using selected clinical tests would be the key issue to successful surgical treatment. Understanding the pathophysiology and biochemistry of tremor production in MS may lead to new therapeutic approaches.

  5. On moduli space of symmetric orthogonal matrices and exclusive Racah matrix S bar for representation R = [3,1] with multiplicities

    Science.gov (United States)

    Morozov, A.

    2017-03-01

    Racah matrices and higher j-symbols are used in description of braiding properties of conformal blocks and in construction of knot polynomials. However, in complicated cases the logic is actually inverted: they are much better deduced from these applications than from the basic representation theory. Following the recent proposal of [1] we obtain the exclusive Racah matrix S bar for the currently-front-line case of representation R = [ 3 , 1 ] with non-trivial multiplicities, where it is actually operator-valued, i.e. depends on the choice of bases in the intertwiner spaces. Effective field theory for arborescent knots in this case possesses gauge invariance, which is not yet properly described and understood. Because of this lack of knowledge a big part (about a half) of S bar needs to be reconstructed from orthogonality conditions. Therefore we discuss the abundance of symmetric orthogonal matrices, to which S bar belongs, and explain that dimension of their moduli space is also about a half of that for the ordinary orthogonal matrices. Thus the knowledge approximately matches the freedom and this explains why the method can work - with some limited addition of educated guesses. A similar calculation for R = [ r , 1 ] for r > 3 should also be doable.

  6. Impact of the Second Semester University Modeling Instruction Course on Students' Representation Choices

    Science.gov (United States)

    McPadden, Daryl; Brewe, Eric

    2017-01-01

    Representation use is a critical skill for learning, problem solving, and communicating in science, especially in physics where multiple representations often scaffold the understanding of a phenomenon. University Modeling Instruction, which is an active-learning, research-based introductory physics curriculum centered on students' use of…

  7. Altered Processing and Integration of Multisensory Bodily Representations and Signals in Eating Disorders: A Possible Path Toward the Understanding of Their Underlying Causes.

    Science.gov (United States)

    Riva, Giuseppe; Dakanalis, Antonios

    2018-01-01

    According to the Diagnostic and Statistical Manual of Mental Disorders (DSM V) eating problems are the clinical core of eating disorders (EDs). However, the importance of shape and weight overvaluation symptoms in these disorders underlines the critical role of the experience of the body in the etiology of EDs. This article suggests that the transdiagnostic centrality of these symptoms in individuals with EDs may reflect a deficit in the processing and integration of multisensory bodily representations and signals. Multisensory body integration is a critical cognitive and perceptual process, allowing the individual to protect and extend her/his boundaries at both the homeostatic and psychological levels. To achieve this goal the brain integrates sensory data arriving from real-time multiple sensory modalities and internal bodily information with predictions made using the stored information about the body from conceptual, perceptual, and episodic memory. In this view the emotional, visual, tactile, proprioceptive and interoceptive deficits reported by many authors in individuals with EDs may reflect a broader impairment in multisensory body integration that affects the individual's abilities: (a) to identify the relevant interoceptive signals that predict potential pleasant (or aversive) consequences; and (b) to modify/correct the autobiographical allocentric (observer view) memories of body related events (self-objectified memories). Based on this view, the article also proposes a strategy, based on new technologies (i.e., virtual reality and brain/body stimulation), for using crossmodal associations to reactivate and correct the multisensory body integration processes.

  8. Altered Processing and Integration of Multisensory Bodily Representations and Signals in Eating Disorders: A Possible Path Toward the Understanding of Their Underlying Causes

    Directory of Open Access Journals (Sweden)

    Giuseppe Riva

    2018-02-01

    Full Text Available According to the Diagnostic and Statistical Manual of Mental Disorders (DSM V eating problems are the clinical core of eating disorders (EDs. However, the importance of shape and weight overvaluation symptoms in these disorders underlines the critical role of the experience of the body in the etiology of EDs. This article suggests that the transdiagnostic centrality of these symptoms in individuals with EDs may reflect a deficit in the processing and integration of multisensory bodily representations and signals. Multisensory body integration is a critical cognitive and perceptual process, allowing the individual to protect and extend her/his boundaries at both the homeostatic and psychological levels. To achieve this goal the brain integrates sensory data arriving from real-time multiple sensory modalities and internal bodily information with predictions made using the stored information about the body from conceptual, perceptual, and episodic memory. In this view the emotional, visual, tactile, proprioceptive and interoceptive deficits reported by many authors in individuals with EDs may reflect a broader impairment in multisensory body integration that affects the individual’s abilities: (a to identify the relevant interoceptive signals that predict potential pleasant (or aversive consequences; and (b to modify/correct the autobiographical allocentric (observer view memories of body related events (self-objectified memories. Based on this view, the article also proposes a strategy, based on new technologies (i.e., virtual reality and brain/body stimulation, for using crossmodal associations to reactivate and correct the multisensory body integration processes.

  9. Social representations of women

    Directory of Open Access Journals (Sweden)

    Álvaro Estramiana, José Luis

    2006-05-01

    Full Text Available Social Representations is one of the most important theories in contemporary social psychology. Since the social psychologist Serge Moscovici developed his theory of social representations to explain how a scientific theory such as the psychoanalysis turns into a common sense knowledge many studies have been done by different social psychologists. The analysis of the social representations of women as represented in myths and popular beliefs is an excellent opportunity to study how this theory can be applied to this representational field. At the same time it makes possible to understand the formation of attitudes towards women

  10. Developing Students' Representational Fluency Using Virtual and Physical Algebra Balances

    OpenAIRE

    Suth, Jennifer; Moyer-Packenham, Patricia S.

    2007-01-01

    Both virtual and physical manipulatives are reported as effective learning tools when used with different groups of students in a variety of contexts to learn mathematical content. The use of multiple representations and the flexibility to translate among those representational forms facilitates students' learning and has the potential to deepen their understanding. This classroom project involved two groups of third-grade students in a week-long unit focusing on algebraic relationships. The ...

  11. The mental representation of the human gait in patients with severe knee osteoarthrosis: a clinical study to aid understanding of impairment and disability.

    Science.gov (United States)

    Jacksteit, Robert; Mau-Moeller, Anett; Behrens, Martin; Bader, Rainer; Mittelmeier, Wolfram; Skripitz, Ralf; Stöckel, Tino

    2018-01-01

    Objectives were (1) to explore differences in gait-specific long-term memory structures and gait performance between knee osteoarthrosis patients and healthy subjects and (2) to identify the extent to which the gait-specific mental representation is associated with gait performance. Cross-sectional study. In total, 18 knee osteoarthrosis patients and 18 control subjects. Spatio-temporal (gait speed, step length) and temporophasic (stance time, swing time, single support time, total double support time) gait parameters and gait variability were measured with an electronic walkway (OptoGait). The mental representation was assessed using the structural dimensional analysis of mental representations (SDA-M). (1) Patients showed significantly longer stance times ( P representation as compared with the healthy controls. (2) Correlation analyses revealed the mental representation of the human gait to be associated with actual gait performance in osteoarthrosis patients. Double support times were positively associated with the structural quality of the mental representation and step length variability was positively associated with the number of sequencing errors in the representation. The gait-specific mental representation and actual gait performance differ between patients with severe knee osteoarthrosis and healthy controls, and both are linked to one another. This finding suggests that musculoskeletal disorders can lead to changes in the mental representation of the gait, and as such the SDA-M could provide useful information to improve the rehabilitation following osteoarthrosis.

  12. Sparse Adaptive Iteratively-Weighted Thresholding Algorithm (SAITA for L p -Regularization Using the Multiple Sub-Dictionary Representation

    Directory of Open Access Journals (Sweden)

    Yunyi Li

    2017-12-01

    Full Text Available Both L 1 / 2 and L 2 / 3 are two typical non-convex regularizations of L p ( 0 < p < 1 , which can be employed to obtain a sparser solution than the L 1 regularization. Recently, the multiple-state sparse transformation strategy has been developed to exploit the sparsity in L 1 regularization for sparse signal recovery, which combines the iterative reweighted algorithms. To further exploit the sparse structure of signal and image, this paper adopts multiple dictionary sparse transform strategies for the two typical cases p ∈ { 1 / 2 ,   2 / 3 } based on an iterative L p thresholding algorithm and then proposes a sparse adaptive iterative-weighted L p thresholding algorithm (SAITA. Moreover, a simple yet effective regularization parameter is proposed to weight each sub-dictionary-based L p regularizer. Simulation results have shown that the proposed SAITA not only performs better than the corresponding L 1 algorithms but can also obtain a better recovery performance and achieve faster convergence than the conventional single-dictionary sparse transform-based L p case. Moreover, we conduct some applications about sparse image recovery and obtain good results by comparison with relative work.

  13. The Development of Multiple-Choice Items Consistent with the AP Chemistry Curriculum Framework to More Accurately Assess Deeper Understanding

    Science.gov (United States)

    Domyancich, John M.

    2014-01-01

    Multiple-choice questions are an important part of large-scale summative assessments, such as the advanced placement (AP) chemistry exam. However, past AP chemistry exam items often lacked the ability to test conceptual understanding and higher-order cognitive skills. The redesigned AP chemistry exam shows a distinctive shift in item types toward…

  14. Analysis of Student Understanding of Science Concepts Including Mathematical Representations: Ph Values and the Relative Differences of pH Values

    Science.gov (United States)

    Park, Eun-Jung; Choi, Kyunghee

    2013-01-01

    In general, mathematical representations such as formulae, numbers, and graphs are the inseparable components in science used to better describe or explain scientific phenomena or knowledge. Regardless of their necessity and benefit, science seems to be difficult for some students, as a result of the mathematical representations and problem…

  15. Representational Thickness

    DEFF Research Database (Denmark)

    Mullins, Michael

    Contemporary communicational and informational processes contribute to the shaping of our physical environment by having a powerful influence on the process of design. Applications of virtual reality (VR) are transforming the way architecture is conceived and produced by introducing dynamic...... elements into the process of design. Through its immersive properties, virtual reality allows access to a spatial experience of a computer model very different to both screen based simulations as well as traditional forms of architectural representation. The dissertation focuses on processes of the current...... by ‘professionals’ to ‘laypeople’. The thesis articulates problems in VR’s current application, specifically the CAVE and Panorama theatres, and seeks an understanding of how these problems may be addressed. The central questions that have motivated this research project are thus: What is architectural VR...

  16. Children's understanding of multiplication and division: Insights from a pooled analysis of seven studies conducted across 7 years.

    Science.gov (United States)

    Dubé, Adam K; Robinson, Katherine M

    2017-11-14

    Research suggests that children's conceptual understanding of multiplication and division is weak and that it remains poor well into the later elementary school years. Further, children's understanding of fundamental concepts such as inversion and associativity does not improve as they progress from grades 6 to 8. Instead, some children simply possess strong understanding while others do not. Other studies have identified an increase across these grades. The present investigation analyses data from seven studies of Grade 6 (n = 226), Grade 7 (n = 221), and Grade 8 (n = 216) children's three-term problem-solving (e.g., 3 × 24 ÷ 24 and 3 × 24 ÷ 6) and provides a unified account of multiplication and division understanding, one in which grade differences and individual variability coexist and are moderated by sex. Statement of contribution What is already known on this subject? Children's conceptual understanding of multiplication and division is weak and it is unclear whether it increases across the key grades of 6-8. Understanding of the inversion and associativity concepts is characterized by high individual variability, but grade and sex have never been found to be a contributing factor. What does this study add? A meta-analysis of seven data sets (n = 643) indicates that grade differences and individual variability coexist and are moderated by sex. Understanding increases across grade only for boys, but an equal number of boys and girls are in the top 10% of conceptual problem-solvers. © 2017 The British Psychological Society.

  17. A Graphical Representation of Multiple Stressor Effects on River Eutrophication as Simulated by a Physics-Based River Quality Model

    Science.gov (United States)

    Hitt, O.; Hutchins, M.

    2016-12-01

    UK river waters face considerable future pressures, primarily from population growth and climate change. In understanding controls on river water quality, experimental studies have successfully identified response to single or paired stressors under controlled conditions. Generalised Linear Model (GLM) approaches are commonly used to quantify stressor-response relationships. To explore a wider variety of stressors physics-based models are used. Our objective is to evaluate how five different types of stressor influence the severity of river eutrophication and its impact on Dissolved Oxygen (DO) an integrated measure of river ecological health. This is done by applying a physics-based river quality model for 4 years at daily time step to a 92 km stretch in the 3445 km2 Thames (UK) catchment. To understand the impact of model structural uncertainty we present results from two alternative formulations of the biological response. Sensitivity analysis carried out using the QUESTOR model (QUality Evaluation and Simulation TOol for River systems) considered gradients of various stressors: river flow, water temperature, urbanisation (abstractions and sewage/industrial effluents), phosphate concentrations in effluents and tributaries and riparian tree shading (modifying the light input). Scalar modifiers applied to the 2009-12 time-series inputs define the gradients. The model has been run for each combination of the values of these 5 variables. Results are analysed using graphical methods in order to identify variation in the type of relationship between different pairs of stressors on the system response. The method allows for all outputs from each combination of stressors to be displayed in one graphic and so showing the results of hundreds of model runs simultaneously. This approach can be carried out for all stressor pairs, and many locations/determinands. Supporting statistical analysis (GLM) reinforces the findings from the graphical analysis. Analysis suggests that

  18. Analyzing social policy: multiple perspectives for critically understanding and evaluating policy

    National Research Council Canada - National Science Library

    O'Connor, Mary Katherine; Netting, F. Ellen

    2011-01-01

    "This unique volume outlines the different frameworks of policy analysis and explains how readers can use research and critical thinking skills to understand the different models from their formation...

  19. Understandings of Nature of Science and Multiple Perspective Evaluation of Science News by Non-science Majors

    Science.gov (United States)

    Leung, Jessica Shuk Ching; Wong, Alice Siu Ling; Yung, Benny Hin Wai

    2015-10-01

    Understandings of nature of science (NOS) are a core component of scientific literacy, and a scientifically literate populace is expected to be able to critically evaluate science in the media. While evidence has remained inconclusive on whether better NOS understandings will lead to critical evaluation of science in the media, this study aimed at examining the correlation therein. Thirty-eight non-science majors, enrolled in a science course for non-specialists held in a local community college, evaluated three health news articles by rating the extent to which they agreed with the reported claims and providing as many justifications as possible. The majority of the participants were able to evaluate and justify their viewpoint from multiple perspectives. Students' evaluation was compared with their NOS conceptions, including the social and cultural embedded NOS, the tentative NOS, the peer review process and the community of practice. Results indicated that participants' understanding of the tentative NOS was significantly correlated with multiple perspective evaluation of science news reports of socioscientific nature (r = 0.434, p media of socioscientific nature. However, the null result for other target NOS aspects in this study suggested a lack of evidence to assume that understanding the social dimensions of science would have significant influence on the evaluation of science in the media. Future research on identifying the reasons for why and why not NOS understandings are applied in the evaluation will move this field forward.

  20. Towards an understanding of hot carrier cooling mechanisms in multiple quantum wells

    Science.gov (United States)

    Conibeer, Gavin; Zhang, Yi; Bremner, Stephen P.; Shrestha, Santosh

    2017-09-01

    Multiple quantum wells have been shown significantly reduced hot carrier cooling rates compared to bulk material and are thus a promising candidate for hot carrier solar cell absorbers. However, the mechanism(s) by which hot carrier cooling is restricted is not clear. A systematic study of carrier cooling rates in GaAs/AlAs multiple quantum wells (MQWs) with either varying barrier thickness or varying well thickness is presented in this paper. These allow an investigation as to whether the mechanisms of either a modification in hot carrier diffusion or a localisation of phonons emitted by hot carriers are primarily responsible for reduced carrier cooling rates. With the conclusion that for the structures investigated the situation is rather more complex with both carrier mobility to modify hot carrier diffusion, different diffusion rates for electrons and holes and reflection and localisation of phonons to enhance phonon bottleneck all playing their parts in modulating phonon reabsorption and hot carrier behaviour.

  1. Chinese and Australian Year 3 Children's Conceptual Understanding of Science: A multiple comparative case study

    Science.gov (United States)

    Tao, Ying; Colette Oliver, Mary; Venville, Grady Jane

    2012-04-01

    Children have formal science instruction from kindergarten in Australia and from Year 3 in China. The purpose of this research was to explore the impact that different approaches to primary science curricula in China and Australia have on children's conceptual understanding of science. Participants were Year 3 children from three schools of high, medium and low socio-economic status in Hunan Province, central south China (n = 135) and three schools of similar socio-economic status in Western Australia (n = 120). The students' understanding was assessed by a science quiz, developed from past Trends in Mathematics and Science Study science released items for primary children. In-depth interviews were carried out to further explore children's conceptual understanding of living things, the Earth and floating and sinking. The results revealed that Year 3 children from schools of similar socio-economic status in the two countries had similar conceptual understandings of life science, earth science and physical science. Further, in both countries, the higher the socio-economic status of the school, the better the students performed on the science quiz and in interviews. Some idiosyncratic strengths and weaknesses were observed, for example, Chinese Year 3 children showed relative strength in classification of living things, and Australian Year 3 children demonstrated better understanding of floating and sinking, but children in both countries were weak in applying and reasoning with complex concepts in the domain of earth science. The results raise questions about the value of providing a science curriculum in early childhood if it does not make any difference to students' conceptual understanding of science.

  2. Understanding Information Technology Investment Decision-Making in the Context of Hotel Global Distribution Systems: a Multiple-Case Study

    OpenAIRE

    Connolly, Daniel J.

    1999-01-01

    UNDERSTANDING INFORMATION TECHNOLOGY INVESTMENT DECISION-MAKING IN THE CONTEXT OF HOTEL GLOBAL DISTRIBUTION SYSTEMS: A MULTIPLE-CASE STUDY by Daniel J. Connolly Dr. Michael D. Olsen, Chair Department of Hospitality and Tourism Management ABSTRACT This study investigates what three large, multinational hospitality companies do in practice when evaluating and making IT investment decisions. This study was launched in an attempt to 1) learn more about ...

  3. Test of Understanding of Vectors: A Reliable Multiple-Choice Vector Concept Test

    Science.gov (United States)

    Barniol, Pablo; Zavala, Genaro

    2014-01-01

    In this article we discuss the findings of our research on students' understanding of vector concepts in problems without physical context. First, we develop a complete taxonomy of the most frequent errors made by university students when learning vector concepts. This study is based on the results of several test administrations of open-ended…

  4. Using Butler to Understand the Multiplicity and Variability of Policy Reception

    Science.gov (United States)

    Gowlett, Christina; Keddie, Amanda; Mills, Martin; Renshaw, Peter; Christie, Pam; Geelan, David; Monk, Sue

    2015-01-01

    Understanding how teachers make sense of education policy is important. We argue that an exploration of teacher reactions to policy requires an engagement with theory focused on the formation of "the subject" since this form of theorisation addresses the creation of a seemingly coherent identity and attitude while acknowledging variation…

  5. Facilitating Evaluations of Innovative, Competence-Based Assessments: Creating Understanding and Involving Multiple Stakeholders

    Science.gov (United States)

    Gulikers, Judith T. M.; Baartman, Liesbeth K. J.; Biemans, Harm J. A.

    2010-01-01

    Schools are held more responsible for evaluating, quality assuring and improving their student assessments. Teachers' lack of understanding of new, competence-based assessments as well as the lack of key stakeholders' involvement, hamper effective and efficient self-evaluations by teachers of innovative, competence-based assessments (CBAs). While…

  6. Facilitating evaluations of innovative, competence-based assessments: creating understanding and involving multiple stakeholders.

    NARCIS (Netherlands)

    Gulikers, J.T.M.; Baartman, L.; Biemans, H.J.A.

    2010-01-01

    Schools are held more responsible for evaluating, quality assuring and improving their student assessments. Teachers’ lack of understanding of new, competence-based assessments as well as the lack of key stakeholders’ involvement, hamper effective and efficient self-evaluations by teachers of

  7. Group and representation theory

    CERN Document Server

    Vergados, J D

    2017-01-01

    This volume goes beyond the understanding of symmetries and exploits them in the study of the behavior of both classical and quantum physical systems. Thus it is important to study the symmetries described by continuous (Lie) groups of transformations. We then discuss how we get operators that form a Lie algebra. Of particular interest to physics is the representation of the elements of the algebra and the group in terms of matrices and, in particular, the irreducible representations. These representations can be identified with physical observables. This leads to the study of the classical Lie algebras, associated with unitary, unimodular, orthogonal and symplectic transformations. We also discuss some special algebras in some detail. The discussion proceeds along the lines of the Cartan-Weyl theory via the root vectors and root diagrams and, in particular, the Dynkin representation of the roots. Thus the representations are expressed in terms of weights, which are generated by the application of the elemen...

  8. Data-mining to build a knowledge representation store for clinical decision support. Studies on curation and validation based on machine performance in multiple choice medical licensing examinations.

    Science.gov (United States)

    Robson, Barry; Boray, Srinidhi

    2016-06-01

    Extracting medical knowledge by structured data mining of many medical records and from unstructured data mining of natural language source text on the Internet will become increasingly important for clinical decision support. Output from these sources can be transformed into large numbers of elements of knowledge in a Knowledge Representation Store (KRS), here using the notation and to some extent the algebraic principles of the Q-UEL Web-based universal exchange and inference language described previously, rooted in Dirac notation from quantum mechanics and linguistic theory. In a KRS, semantic structures or statements about the world of interest to medicine are analogous to natural language sentences seen as formed from noun phrases separated by verbs, prepositions and other descriptions of relationships. A convenient method of testing and better curating these elements of knowledge is by having the computer use them to take the test of a multiple choice medical licensing examination. It is a venture which perhaps tells us almost as much about the reasoning of students and examiners as it does about the requirements for Artificial Intelligence as employed in clinical decision making. It emphasizes the role of context and of contextual probabilities as opposed to the more familiar intrinsic probabilities, and of a preliminary form of logic that we call presyllogistic reasoning. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Understanding and meeting injection device needs in multiple sclerosis: a survey of patient attitudes and practices

    Directory of Open Access Journals (Sweden)

    Russell S

    2011-03-01

    Full Text Available Elisabetta Verdun di Cantogno1, Susan Russell2, Tom Snow21Global Clinical Development Unit, Merck Serono S.A. – Geneva, Switzerland; 2Global Marketing, Merck Serono S.A. – Geneva, SwitzerlandBackground: All established disease-modifying drugs for multiple sclerosis require parenteral administration, which can cause difficulties for some patients, sometimes leading to suboptimal adherence. A new electronic autoinjection device has been designed to address these issues.Methods: Patients with relapsing multiple sclerosis currently receiving subcutaneous or intramuscular interferon beta-1a, interferon beta-1b, or glatiramer acetate completed an online questionnaire (July 4–25, 2008 that surveyed current injection practices, experiences with current injection methods, and impressions and appeal of the new device.Results: In total, 422 patients completed the survey, of whom 44% used autoinjectors, 43% prefilled syringes, and 13% syringes and vials; overall, 66% currently self-injected. Physical and psychological barriers to self-injection included difficulty with injections, needle phobia, and concerns over correct injection technique. Only 40% of respondents were “very satisfied” with their current injection method. The new electronic autoinjector was rated as “very appealing” by 65% of patients. The benefits of the new device included the ability to customize injection settings and to review dosing history.Conclusion: New technologies may help patients overcome physical and psychological barriers to self-injection. The combination of a reliable and flexible autoinjection device with dose-monitoring technology may improve communication between health care professionals and patients, and improve treatment adherence.Keywords: adherence, autoinjection, subcutaneous interferon beta-1a, multiple sclerosis 

  10. Resistance and change: a multiple streams approach to understanding health policy making in Ghana.

    Science.gov (United States)

    Kusi-Ampofo, Owuraku; Church, John; Conteh, Charles; Heinmiller, B Timothy

    2015-02-01

    Although much has been written on health policy making in developed countries, the same cannot be said of less developed countries, especially in Africa. Drawing largely on available historical and government records, newspaper publications, parliamentary Hansards, and published books and articles, this article uses John W. Kingdon's multiple streams framework to explain how the problem, politics, and policy streams converged for Ghana's National Health Insurance Scheme (NHIS) to be passed into law in 2003. The article contends that a change in government in the 2000 general election opened a "policy window" for eventual policy change from "cash-and-carry" to the NHIS. Copyright © 2015 by Duke University Press.

  11. Using geometric algebra to understand pattern rotations in multiple mirror optical systems

    International Nuclear Information System (INIS)

    Hanlon, J.; Ziock, H.

    1997-01-01

    Geometric Algebra (GA) is a new formulation of Clifford Algebra that includes vector analysis without notation changes. Most applications of Ga have been in theoretical physics, but GA is also a very good analysis tool for engineering. As an example, the authors use GA to study pattern rotation in optical systems with multiple mirror reflections. The common ways to analyze pattern rotations are to use rotation matrices or optical ray trace codes, but these are often inconvenient. The authors use GA to develop a simple expression for pattern rotation that is useful for designing or tolerancing pattern rotations in a multiple mirror optical system by inspection. Pattern rotation is used in many optical engineering systems, but it is not normally covered in optical system engineering texts. Pattern rotation is important in optical systems such as: (1) the 192 beam National ignition Facility (NIF), which uses square laser beams in close packed arrays to cut costs; (2) visual optical systems, which use pattern rotation to present the image to the observer in the appropriate orientation, and (3) the UR90 unstable ring resonator, which uses pattern rotation to fill a rectangular laser gain region and provide a filled-in laser output beam

  12. Young adult Ecstasy users and multiple sexual partners: understanding the factors underlying this HIV risk practice.

    Science.gov (United States)

    Sterk, Claire E; Klein, Hugh; Elifson, Kirk W

    2008-09-01

    The purposes of this study are to (1) examine the extent to which young adult Ecstasy users recently reported having had multiple sex partners and (2) identify the factors predictive of engaging in this behavior. Potential predictors included demographic characteristics, background and experiences measures, childhood maltreatment experiences, substance use variables, and measures assessing psychological/psychosocial functioning. This research is based on a sample of 283 young adult recurrent users of the drug, Ecstasy. Study participants were recruited in Atlanta, Georgia between August 2002 and August 2004 using a targeted sampling and ethnographic mapping approach. Interviews took approximately two hours to complete. Nearly one-third of the study participants had more than one sex partner during the preceding month, and sexual protection rates tended to be low. Multivariate logistic regression analysis revealed seven predictors associated with an increased likelihood of having multiple sex partners: (1) being nonwhite, (2) knowing someone who was HIV-positive, (3) younger age of first sexual experience, (4) using Ecstasy for its touch-enhancing qualities, (5) higher self-esteem, (6) handling disagreements more dysfunctionally, and (7) not being involved in a romantic relationship. The HIV prevention- and intervention-related implications of these findings are discussed.

  13. Understanding biology to tackle the disease: Multiple myeloma from bench to bedside, and back.

    Science.gov (United States)

    Bianchi, Giada; Anderson, Kenneth C

    2014-01-01

    Multiple myeloma (MM) is a cancer of antibody-producing plasma cells. The pathognomonic laboratory finding is a monoclonal immunoglobulin or free light chain in the serum and/or urine in association with bone marrow infiltration by malignant plasma cells. MM develops from a premalignant condition, monoclonal gammopathy of undetermined significance (MGUS), often via an intermediate stage termed smoldering multiple myeloma (SMM), which differs from active myeloma by the absence of disease-related end-organ damage. Unlike MGUS and SMM, active MM requires therapy. Over the past 6 decades, major advancements in the care of MM patients have occurred, in particular, the introduction of novel agents (ie, proteasome inhibitors, immunomodulatory agents) and the implementation of hematopoietic stem cell transplantation in suitable candidates. The effectiveness and good tolerability of novel agents allowed for their combined use in induction, consolidation, and maintenance therapy, resulting in deeper and more sustained clinical response and extended progression-free and overall survival. Previously a rapidly lethal cancer with few therapeutic options, MM is the hematologic cancer with the most novel US Food and Drug Administration-approved drugs in the past 15 years. These advances have resulted in more frequent long-term remissions, transforming MM into a chronic illness for many patients. © 2014 American Cancer Society.

  14. The Story-Presenting Method: a Method for Constructing Multiple Viewpoints to Understand Different Cultures.

    Science.gov (United States)

    Watanabe, Tadaharu

    2017-09-01

    This study will show the results of four dialogical cultural exchange classes, which were held between Japanese and Chinese high school students, and examine the shifts in students' viewpoints and changes in cultural understandings that occurred during those classes. In the first cultural exchange class, students of both countries read a story which described an older student who carelessly wore a T-shirt inside out, and younger students passed by without greeting him. Students of both countries were then asked to write their comments about it. From the second to the fourth class, students discussed the story with each other through exchanging their comments. By presenting another story, which introduced the viewpoint of a third person, and asking them questions that allowed them to reflect on their lives, students also experienced four different viewpoints during these cultural exchange classes. At the beginning of the cultural exchange, students of both countries tended to focus on the similarities in each other's comments, which led to the closing down of the discussion. However, through discussions and experiencing the four different viewpoints, they found there are some essential differences between them around 'ways of greeting' and 'hierarchical relationships between older and younger students', which motivated them to understand their counterparts' culture. Moreover, in the last comments of these cultural exchange classes, it was found that they acquired the viewpoints of cultural others. Given the results of these classes, it is shown that it is effective to present various stories to stimulate cultural understanding.

  15. Diffusion equation representation of multiple-scatter gamma ray flux for 59.5, 122.1 and 279.2 keV point sources through water and graphite media

    International Nuclear Information System (INIS)

    Swarup, J.; Peshori, L.H.

    1986-01-01

    The transmitted γ fluxes for three sources, namely, 241 Am, 57 Co and 203 Hg, for the total spectrum as well as for the multiple-scatter peak, for different thicknesses of the water and graphite media have been represented by the diffusion formula, I=S/(4πDx esup(kx)), and compared with the earlier representation, I=I 0 esup(-ax). It is found that both the representations are equally good for the medium thicknesses taken in these measurements. (author)

  16. APPLICATION EQUIPMENT MULTIPLICATION TABLES FIGURE TO IMPROVE UNDERSTANDING ABOUT STUDENTS IN DAILY LIFE STORIES

    Directory of Open Access Journals (Sweden)

    Warliah -

    2016-05-01

    Full Text Available Abstract. The research is motivated by the problems in the learning of mathematics in class V SDN Cilengkrang sumedang uatara districts, namely students have difficulty in arithmetic operation about the story. Research aimed at effective mathematics learning in arithmetic operation about the story. The method used is classroom action research. The results showed, in general, in cycle 1, the level of achievement of learning outcomes in the concept of the fifth grade math story problems by 37% with an average value of 70. Based on the improvement in cycle 1, then the results obtained from silus 2; students who answered questions of teachers and the level of achievement of learning outcomes by 92 %% with an average value of 82. Learning mathematics on the material about the concept of the story of multiplication in everyday life using props multiplication tables, and engineering skills of teachers, methods vary , classroom management discipline, was able to change student attitudes among students in the mastery of learning materials to increase, can do the math task, and students are responsible for the mathematical task.   Keywords: story problems, tool multiplication tables.   Abstrak.  Penelitian ini dilatarbelakangi oleh adanya permasalahan dalam pembelajaran matematika di kelas V SDN Cilengkrang kecamatan Sumedang Utara, yaitu siswa mengalami kesulitan dalam operasi hitung soal cerita. Penelitian bertujuan pembelajaran matematika yang efektif dalam operasi hitung soal cerita. Metode yang digunakan yaitu penelitian tindakan kelas. Hasil penelitian menunjukkan, secara umum pada siklus 1, tingkat pencapaian hasil belajar pada konsep soal cerita matematika  kelas V sebesar 37 % dengan rata-rata nilai sebesar 70. Berdasarkan hasil perbaikan pada siklus 1, maka didapatkan hasil dari silus 2 ; siswa yang menjawab pertanyaan guru dan tingkat pencapaian hasil belajar sebesar 92 %% dengan rata-rata nilai 82. Pembelajaran matematika pada materi soal

  17. Understanding the Roles of the Kynurenine Pathway in Multiple Sclerosis Progression

    Directory of Open Access Journals (Sweden)

    Chai K. Lim

    2010-08-01

    Full Text Available The kynurenine pathway (KP is a major degradative pathway of tryptophan ultimately leading to the production of nicotinamide adenine dinucleotide (NAD+ and is also one of the major regulatory mechanisms of the immune response. The KP is known to be involved in several neuroinflammatory disorders including Alzheimer’s disease, amyotrophic lateral sclerosis, AIDS dementia complex, Parkinson’s disease, schizophrenia, Huntington’s disease and brain tumours. However, the KP remains a relatively new topic for the field of multiple sclerosis (MS. Over the last 2–3 years, some evidence has progressively emerged suggesting that the KP is likely to be involved in the pathogenesis of autoimmune diseases especially MS. Some KP modulators are already in clinical trials for other inflammatory diseases and would potentially provide a new and important therapeutic strategy for MS patients. This review summarizes the known relationships between the KP and MS.

  18. Understanding the Roles of the Kynurenine Pathway in Multiple Sclerosis Progression

    Directory of Open Access Journals (Sweden)

    Chai K. Lim

    2010-01-01

    Full Text Available The kynurenine pathway (KP is a major degradative pathway of tryptophan ultimately leading to the production of nicotinamide adenine dinucleotide (NAD + and is also one of the major regulatory mechanisms of the immune response. The KP is known to be involved in several neuroinflammatory disorders including Alzheimer's disease, amyotrophic lateral sclerosis, AIDS dementia complex, Parkinson's disease, schizophrenia, Huntington's disease and brain tumours. However, the KP remains a relatively new topic for the field of multiple sclerosis (MS. Over the last 2–3 years, some evidence has progressively emerged suggesting that the KP is likely to be involved in the pathogenesis of autoimmune diseases especially MS. Some KP modulators are already in clinical trials for other inflammatory diseases and would potentially provide a new and important therapeutic strategy for MS patients. This review summarizes the known relationships between the KP and MS.

  19. A mechanistic understanding of the wear coefficient: From single to multiple asperities contact

    Science.gov (United States)

    Frérot, Lucas; Aghababaei, Ramin; Molinari, Jean-François

    2018-05-01

    Sliding contact between solids leads to material detaching from their surfaces in the form of debris particles, a process known as wear. According to the well-known Archard wear model, the wear volume (i.e. the volume of detached particles) is proportional to the load and the sliding distance, while being inversely proportional to the hardness. The influence of other parameters are empirically merged into a factor, referred to as wear coefficient, which does not stem from any theoretical development, thus limiting the predictive capacity of the model. Based on a recent understanding of a critical length-scale controlling wear particle formation, we present two novel derivations of the wear coefficient: one based on Archard's interpretation of the wear coefficient as the probability of wear particle detachment and one that follows naturally from the up-scaling of asperity-level physics into a generic multi-asperity wear model. As a result, the variation of wear rate and wear coefficient are discussed in terms of the properties of the interface, surface roughness parameters and applied load for various rough contact situations. Both new wear interpretations are evaluated analytically and numerically, and recover some key features of wear observed in experiments. This work shines new light on the understanding of wear, potentially opening a pathway for calculating the wear coefficient from first principles.

  20. Categorification and higher representation theory

    CERN Document Server

    Beliakova, Anna

    2017-01-01

    The emergent mathematical philosophy of categorification is reshaping our view of modern mathematics by uncovering a hidden layer of structure in mathematics, revealing richer and more robust structures capable of describing more complex phenomena. Categorified representation theory, or higher representation theory, aims to understand a new level of structure present in representation theory. Rather than studying actions of algebras on vector spaces where algebra elements act by linear endomorphisms of the vector space, higher representation theory describes the structure present when algebras act on categories, with algebra elements acting by functors. The new level of structure in higher representation theory arises by studying the natural transformations between functors. This enhanced perspective brings into play a powerful new set of tools that deepens our understanding of traditional representation theory. This volume exhibits some of the current trends in higher representation theory and the diverse te...

  1. Multiple stab wounds: understanding the manner of death through the psychological autopsy.

    Science.gov (United States)

    Di Vella, G; Grattagliano, I; Curti, S; Catanesi, R; Sullivan, M K; Tattoli, L

    2017-01-01

    A 48-year-old physical therapist with no history of psychiatric disorders or suicidal tendencies was found dead by his relatives inside his apartment. Multiple stab wounds were present on the chest and the abdomen. Several more superficial cuts were also seen on the neck and the left wrist. At the death scene, there was a large pool of blood in the room, with secondary droplets and stains; a kitchen knife was found beside the body, and a suicide note on a table. Especially the number of wounds raised strong suspicion of a homicide in the first instance but some circumstances (the farewell letter, the absence of clothing injuries, no signs of third-party involvement) and autopsy findings (absence of defense or blunt injuries, the localization of the wounds, the presence of hesitation marks) pointed toward a suicide etiology. Because of the many stab injuries and the lack of a psychiatric history, further forensic investigations were required including a so-called psychological autopsy. This case report highlights that only a comprehensive interpretation of all the elements (circumstances, the scene of death, autopsy findings, and psychological autopsy) can lead to the correct solution of atypical cases of suicide.

  2. Understanding the free energy barrier and multiple timescale dynamics of charge separation in organic photovoltaic cells

    Science.gov (United States)

    Yan, Yaming; Song, Linze; Shi, Qiang

    2018-02-01

    By employing several lattice model systems, we investigate the free energy barrier and real-time dynamics of charge separation in organic photovoltaic (OPV) cells. It is found that the combined effects of the external electric field, entropy, and charge delocalization reduce the free energy barrier significantly. The dynamic disorder reduces charge carrier delocalization and results in the increased charge separation barrier, while the effect of static disorder is more complicated. Simulation of the real-time dynamics indicates that the free charge generation process involves multiple time scales, including an ultrafast component within hundreds of femtoseconds, an intermediate component related to the relaxation of the hot charge transfer (CT) state, and a slow component on the time scale of tens of picoseconds from the thermally equilibrated CT state. Effects of hot exciton dissociation as well as its dependence on the energy offset between the Frenkel exciton and the CT state are also analyzed. The current results indicate that only a small energy offset between the band gap and the lowest energy CT state is needed to achieve efficient free charge generation in OPV devices, which agrees with recent experimental findings.

  3. Understanding the free energy barrier and multiple timescale dynamics of charge separation in organic photovoltaic cells.

    Science.gov (United States)

    Yan, Yaming; Song, Linze; Shi, Qiang

    2018-02-28

    By employing several lattice model systems, we investigate the free energy barrier and real-time dynamics of charge separation in organic photovoltaic (OPV) cells. It is found that the combined effects of the external electric field, entropy, and charge delocalization reduce the free energy barrier significantly. The dynamic disorder reduces charge carrier delocalization and results in the increased charge separation barrier, while the effect of static disorder is more complicated. Simulation of the real-time dynamics indicates that the free charge generation process involves multiple time scales, including an ultrafast component within hundreds of femtoseconds, an intermediate component related to the relaxation of the hot charge transfer (CT) state, and a slow component on the time scale of tens of picoseconds from the thermally equilibrated CT state. Effects of hot exciton dissociation as well as its dependence on the energy offset between the Frenkel exciton and the CT state are also analyzed. The current results indicate that only a small energy offset between the band gap and the lowest energy CT state is needed to achieve efficient free charge generation in OPV devices, which agrees with recent experimental findings.

  4. Advancing the understanding of progression in multiple sclerosis: an interview with Shibeshih Belachew.

    Science.gov (United States)

    Belachew, Shibeshih

    2018-02-01

    Shibeshih Belachew speaks to Laura Dormer, Commissioning Editor: Dr Shibeshih Belachew, MD, PhD, is a Senior Medical Director for Multiple Sclerosis (MS) Disease Area in Global Product Development Medical Affairs at Roche (Basel, Switzerland). Prior to joining Roche in January 2016, he was Director of MS Franchise and Head of Medical Director's office for Biogen Region Europe and Canada. Previously at Biogen he also served as a Director in Global Neurology for the natalizumab program in Cambridge (MA, USA). Prior to joining industry, he was a Clinical Professor of Neurology at the University of Liège in Belgium. Shibeshih completed neurology postgraduate training at the University of Liège and has a PhD in Biomedical Science in the field of Developmental Neurobiology. Shibeshih has been a post-doctoral fellow in the Laboratory of Cellular and Synaptic Neurophysiology at the National Institutes of Health (Bethesda, MD, USA) and later at the Center for Neuroscience Research of Children's National Medical Center in Washington DC. He is a member of the Belgian Neurological Society.

  5. Poetic representation

    DEFF Research Database (Denmark)

    Wulf-Andersen, Trine Østergaard

    2012-01-01

    , and dialogue, of situated participants. The article includes a lengthy example of a poetic representation of one participant’s story, and the author comments on the potentials of ‘doing’ poetic representations as an example of writing in ways that challenges what sometimes goes unasked in participative social...

  6. Towards a Better Understanding of CMMI and Agile Integration - Multiple Case Study of Four Companies

    Science.gov (United States)

    Pikkarainen, Minna

    The amount of software is increasing in the different domains in Europe. This provides the industries in smaller countries good opportunities to work in the international markets. Success in the global markets however demands the rapid production of high quality, error free software. Both CMMI and agile methods seem to provide a ready solution for quality and lead time improvements. There is not, however, much empirical evidence available either about 1) how the integration of these two aspects can be done in practice or 2) what it actually demands from assessors and software process improvement groups. The goal of this paper is to increase the understanding of CMMI and agile integration, in particular, focusing on the research question: how to use ‘lightweight’ style of CMMI assessments in agile contexts. This is done via four case studies in which assessments were conducted using the goals of CMMI integrated project management and collaboration and coordination with relevant stakeholder process areas and practices from XP and Scrum. The study shows that the use of agile practices may support the fulfilment of the goals of CMMI process areas but there are still many challenges for the agile teams to be solved within the continuous improvement programs. It also identifies practical advices to the assessors and improvement groups to take into consideration when conducting assessment in the context of agile software development.

  7. Multiple stressor effects in Chlamydomonas reinhardtii – Toward understanding mechanisms of interaction between effects of ultraviolet radiation and chemical pollutants

    Energy Technology Data Exchange (ETDEWEB)

    Korkaric, Muris [Eawag, Swiss Federal Institute of Aquatic Science and Technology, Department of Environmental Toxicology, 8600, Duebendorf (Switzerland); ETH Zürich, Institute of Biogeochemistry and Pollutant Dynamics, 8092 Zürich (Switzerland); Behra, Renata; Fischer, Beat B. [Eawag, Swiss Federal Institute of Aquatic Science and Technology, Department of Environmental Toxicology, 8600, Duebendorf (Switzerland); Junghans, Marion [Swiss Center for Applied Ecotoxicology Eawag-EPFL, 8600, Duebendorf (Switzerland); Eggen, Rik I.L., E-mail: rik.eggen@eawag.ch [Eawag, Swiss Federal Institute of Aquatic Science and Technology, Department of Environmental Toxicology, 8600, Duebendorf (Switzerland); ETH Zürich, Institute of Biogeochemistry and Pollutant Dynamics, 8092 Zürich (Switzerland)

    2015-05-15

    Highlights: • Systematic study of multiple stressor effects of UVR and chemicals in C. reinhardtii. • UVR and chemicals did not act independently on algal photosynthesis and reproduction. • Multiple stressor effects of UVR and chemicals depended on chemical MOA. • Synergistic effect interactions not limited to oxidative stress inducing chemicals. • Multiple MOAs of UVR may limit applicability of current prediction models. - Abstract: The effects of chemical pollutants and environmental stressors, such as ultraviolet radiation (UVR), can interact when organisms are simultaneously exposed, resulting in higher (synergistic) or lower (antagonistic) multiple stressor effects than expected based on the effects of single stressors. Current understanding of interactive effects is limited due to a lack of mechanism-based multiple stressor studies. It has been hypothesized that effect interactions may generally occur if chemical and non-chemical stressors cause similar physiological effects in the organism. To test this hypothesis, we exposed the model green alga Chlamydomonas reinhardtii to combinations of UVR and single chemicals displaying modes of action (MOA) similar or dissimilar to the impact of UVR on photosynthesis. Stressor interactions were analyzed based on the independent action model. Effect interactions were found to depend on the MOA of the chemicals, and also on their concentrations, the exposure time and the measured endpoint. Indeed, only chemicals assumed to cause effects on photosynthesis similar to UVR showed interactions with UVR on photosynthetic yield: synergistic in case of Cd(II) and paraquat and antagonistic in case of diuron. No interaction on photosynthesis was observed for S-metolachlor, which acts dissimilarly to UVR. However, combined effects of S-metolachlor and UVR on algal reproduction were synergistic, highlighting the importance of considering additional MOA of UVR. Possible mechanisms of stressor effect interactions are

  8. Multiple stressor effects in Chlamydomonas reinhardtii – Toward understanding mechanisms of interaction between effects of ultraviolet radiation and chemical pollutants

    International Nuclear Information System (INIS)

    Korkaric, Muris; Behra, Renata; Fischer, Beat B.; Junghans, Marion; Eggen, Rik I.L.

    2015-01-01

    Highlights: • Systematic study of multiple stressor effects of UVR and chemicals in C. reinhardtii. • UVR and chemicals did not act independently on algal photosynthesis and reproduction. • Multiple stressor effects of UVR and chemicals depended on chemical MOA. • Synergistic effect interactions not limited to oxidative stress inducing chemicals. • Multiple MOAs of UVR may limit applicability of current prediction models. - Abstract: The effects of chemical pollutants and environmental stressors, such as ultraviolet radiation (UVR), can interact when organisms are simultaneously exposed, resulting in higher (synergistic) or lower (antagonistic) multiple stressor effects than expected based on the effects of single stressors. Current understanding of interactive effects is limited due to a lack of mechanism-based multiple stressor studies. It has been hypothesized that effect interactions may generally occur if chemical and non-chemical stressors cause similar physiological effects in the organism. To test this hypothesis, we exposed the model green alga Chlamydomonas reinhardtii to combinations of UVR and single chemicals displaying modes of action (MOA) similar or dissimilar to the impact of UVR on photosynthesis. Stressor interactions were analyzed based on the independent action model. Effect interactions were found to depend on the MOA of the chemicals, and also on their concentrations, the exposure time and the measured endpoint. Indeed, only chemicals assumed to cause effects on photosynthesis similar to UVR showed interactions with UVR on photosynthetic yield: synergistic in case of Cd(II) and paraquat and antagonistic in case of diuron. No interaction on photosynthesis was observed for S-metolachlor, which acts dissimilarly to UVR. However, combined effects of S-metolachlor and UVR on algal reproduction were synergistic, highlighting the importance of considering additional MOA of UVR. Possible mechanisms of stressor effect interactions are

  9. Assessing understanding of individual risk and symptoms of progressive multifocal leukoencephalopathy in patients prescribed natalizumab for multiple sclerosis.

    Science.gov (United States)

    Rath, Louise; Vijiaratnam, Nirosen; Skibina, Olga

    2017-02-01

    Natalizumab, a monoclonal antibody directed against α4 integrin, is a highly efficacious treatment commonly used in relapsing remitting multiple sclerosis. Natalizumab is associated with the potentially fatal, rare, demyelinating, opportunistic brain infection, progressive multifocal leukoencephalopathy (PML). Prognosis and disability from PML are determined by early diagnosis. Written tools are mandated in Australia and other prescribing countries with the aim to help patients understand the risks associated with treatment and ensure familiarity with the early symptoms of PML. We aimed to assess if these tools achieve such an outcome. A cross-sectional survey was conducted using a convenience sample of multiple sclerosis patients prescribed natalizumab presenting to the infusion centre at a major tertiary hospital. Patients were offered a multi-choice questionnaire to assess their knowledge on the treatment risks and surveillance requirements of their therapy. Three specific questions were highlighted by the researchers as crucial to patient understanding of PML and defined as basic knowledge. A total of 48 patients in our hospital was prescribed natalizumab; 37 responded. A total of 16 (43.2%) patients answered all three basic knowledge questions correctly. There was no difference in the ability to answer these questions based on length of treatment or co-ownership knowledge between patients with base knowledge and without. Natalizumab is associated with an increased risk of PML. Early detection and treatment of PML results in improved patient outcomes. Patient knowledge and co-partnership in the utilisation of PML risk tools is relevant in ensuring early detection. Our findings question the ability of currently sanctioned tools to inform patients of basic knowledge of PML and their risk of developing PML. A future study with a repetitive education approach and repeating the questionnaire at multiple time points would be of interest. © 2016 Royal Australasian

  10. Imitation and the Dialectic of Representation.

    Science.gov (United States)

    Zelazo, Philip David; Lourenco, Stella Felix

    2003-01-01

    Describes a theory of the understanding and use of representations, drawing heavily on Paul Ricoeur's and James Mark Baldwin's theories. Presents this theory as construing representation as intrinsically mimetic, characterizing the development of representational understanding as internalization, and emphasizing the importance of self-reflection…

  11. The relationship between priming and linguistic representations is mediated by processing constraints.

    Science.gov (United States)

    Slevc, L Robert; Ivanova, Iva

    2017-01-01

    Understanding the nature of linguistic representations undoubtedly will benefit from multiple types of evidence, including structural priming. Here, we argue that successfully gaining linguistic insights from structural priming requires us to better understand (1) the precise mappings between linguistic input and comprehenders' syntactic knowledge; and (2) the role of cognitive faculties such as memory and attention in structural priming.

  12. Multiplicity

    Science.gov (United States)

    1991-04-01

    Virginia, 388 U.S. 1 (1967)(criminal statute prohibiting interracial marriages held unconstitutional violation of the Equal Protection and Due Process...such sentences does not violate the Constitution."°2 7 In effect , the double jeopardy protection from multiple punishments is coextensive with...unaware of what it accomplished . . . . In effect , the Blockburger test establishes a presumption of legislative intent: if each of two statutes

  13. Multiple stressor effects in Chlamydomonas reinhardtii--toward understanding mechanisms of interaction between effects of ultraviolet radiation and chemical pollutants.

    Science.gov (United States)

    Korkaric, Muris; Behra, Renata; Fischer, Beat B; Junghans, Marion; Eggen, Rik I L

    2015-05-01

    The effects of chemical pollutants and environmental stressors, such as ultraviolet radiation (UVR), can interact when organisms are simultaneously exposed, resulting in higher (synergistic) or lower (antagonistic) multiple stressor effects than expected based on the effects of single stressors. Current understanding of interactive effects is limited due to a lack of mechanism-based multiple stressor studies. It has been hypothesized that effect interactions may generally occur if chemical and non-chemical stressors cause similar physiological effects in the organism. To test this hypothesis, we exposed the model green alga Chlamydomonas reinhardtii to combinations of UVR and single chemicals displaying modes of action (MOA) similar or dissimilar to the impact of UVR on photosynthesis. Stressor interactions were analyzed based on the independent action model. Effect interactions were found to depend on the MOA of the chemicals, and also on their concentrations, the exposure time and the measured endpoint. Indeed, only chemicals assumed to cause effects on photosynthesis similar to UVR showed interactions with UVR on photosynthetic yield: synergistic in case of Cd(II) and paraquat and antagonistic in case of diuron. No interaction on photosynthesis was observed for S-metolachlor, which acts dissimilarly to UVR. However, combined effects of S-metolachlor and UVR on algal reproduction were synergistic, highlighting the importance of considering additional MOA of UVR. Possible mechanisms of stressor effect interactions are discussed. Copyright © 2015 Elsevier B.V. All rights reserved.

  14. The 'subjective' risk mapping: understanding of a technical risk representation by a professional group; La cartographie 'subjective' des risques: comprendre la representation d'un risque technique par un groupe professionnel

    Energy Technology Data Exchange (ETDEWEB)

    Bertin, H.; Deleuze, G. [Electricite de France (EDF-RD), Management des Risques Industriels, 92 - Clamart (France)

    2006-07-01

    The paper presents the application of a particular way to make risk maps, called 'subjective risk mapping'. It has been used to understand how the risk of tube rupture under pressure is understood, defined, and set in perspective with other risks in a professional group working in an industrial plant. (authors)

  15. Meaningful Representations Prevent Catastrophic Interference

    NARCIS (Netherlands)

    Bieger, J.; Sprinkhuizen-Kuyper, I.G.; Rooij, I.J.E.I. van; Calders, T.; Tuyls, K.; Pechenizkiy, M.

    2009-01-01

    Artificial Neural Networks (ANNs) attempt to mimic human neural networks in order to perform tasks. In order to do this, tasks need to be represented in ways that the network understands. In ANNs these representations are often arbitrary, whereas in humans it seems that these representations are

  16. Understanding the Risk to Neotropical Migrant Bird Species of Multiple Human-Caused Stressors: Elucidating Processes Behind the Patterns.

    Directory of Open Access Journals (Sweden)

    Ralph S. Hames

    2006-06-01

    Full Text Available Ubiquitous human-caused changes to the environment act as multiple stressors for organisms in the wild, and the effects of these stressors may be synergistic, rather than merely additive, with unexpected results. However, understanding how focal organisms respond to these stressors is crucial for conservation planning for these species. We propose a paradigm that alternates extensive, broadscale data collection by volunteer collaborators to document patterns of response, with intensive fine-scale studies by professional researchers, to elucidate the processes underlying these patterns. We demonstrate this technique, building on our existing work linking patterns of population declines in the Wood Thrush (Hylocichla mustelina to synergistic effects of acid rain and habitat fragmentation. To better understand the processes behind these patterns, we use a simple protocol to explore linkages between acid rain, leaching of calcium from the soil, and declines in the abundance of calcium-rich invertebrate prey species, which may be necessary for successful breeding by this thrush. We sampled at 40 study sites across New York that were chosen based on estimated acid deposition and soil properties. Our results show that the calcium content of the soils sampled is proportional to the soil pH, that the abundance of calcium-rich invertebrate prey tracks soil properties, and that the presence of a breeding Wood Thrush was correctly predicted in >70% of study sites by the biomass of calcium-rich prey, and in particular, the biomass of myriapods (Diplopoda. We show that a simple repeatable protocol, suitable for use by volunteers across broad geographic extents and ranges of habitat fragmentation, can help us understand the reactions of some forest birds to acid rain in combination with habitat fragmentation. We detail the development of this protocol for volunteers in the Birds in Forested Landscapes project, and describe future plans.

  17. Representational Machines

    DEFF Research Database (Denmark)

    to the enterprises of the medium. This is the subject of Representational Machines: How photography enlists the workings of institutional technologies in search of establishing new iconic and social spaces. Together, the contributions to this edited volume span historical epochs, social environments, technological...

  18. Development and Application of a Two-Tier Multiple Choice Diagnostic Instrument To Assess High School Students' Understanding of Inorganic Chemistry Qualitative Analysis.

    Science.gov (United States)

    Tan, Kim Chwee Daniel; Goh, Ngoh Khang; Chia, Lian Sai; Treagust, David F.

    2002-01-01

    Describes the development and application of a two-tier multiple choice diagnostic instrument to assess high school students' understanding of inorganic chemistry qualitative analysis. Shows that the Grade 10 students had difficulty understanding the reactions involved in the identification of cations and anions, for example, double decomposition…

  19. Multiple environmental tracers for a better understanding of water flux in a wetland area (La Bassée, France)

    International Nuclear Information System (INIS)

    Gourcy, L.; Brenot, A.

    2011-01-01

    Understanding water exchange between groundwater and streams, or groundwater/surface-water relationships, is of primary importance for solving conflicts related to water use and for restoring water ecosystems. To this end, a combination of classic geochemical tools and isotopic tools were tested on the Bassée study site, located in the alluvial plain of the River Seine, to see whether they are relevant for tracing multiple and complex groundwater/surface-water relationships. The Ca/Sr ratio associated with Sr isotopes shows contrasted values and suggests that infiltration of surface water to groundwater increases when approaching the Seine. Furthermore, stable isotopes of the water molecule indicate that water from gravel-pit lakes may infiltrate into groundwater. Tritium and CFC tools confirmed surface-water influence on the Alluvial and Chalk aquifers. This geochemical approach, tested on the Bassée site, clearly demonstrates the need of using various geochemical tools for describing groundwater/surface-water relationships, and can be conclusively addressed to other case studies for helping decision makers in their management of natural water resources.

  20. Understanding unexpected courses of multiple sclerosis among patients using complementary and alternative medicine: A travel from recipient to explorer

    Directory of Open Access Journals (Sweden)

    Anita Salamonsen

    2010-07-01

    Full Text Available Complementary and alternative medicine (CAM is frequently used by patients with multiple sclerosis (MS. Some MS patients experience unexpected improvements of symptoms, which they relate to their use of CAM. The aim of this study was to obtain knowledge and develop understandings of such self-defined unexpected improvement of MS symptoms. Two cases were constructed based on documents and 12 qualitative interviews. Our aim was not to make generalisations from the cases, but to transfer knowledge as working hypotheses. We identified four health-related change processes: the process of losing bodily competence; the process of developing responsibility; the process of taking control; and the process of choosing CAM. The patients explained unexpected improvements in their MS symptoms as results of their own efforts including their choice and use of CAM. In our theoretical interpretations, we found the patients’ redefinition of history, the concept of treatment and the importance of conventional health care to be essential, and leading to a change of patients’ position towards conventional health care from recipients to explorers. The explorers can be perceived as boundary walkers reflecting limitations within the conventional health care system and as initiators regarding what MS patients find useful in CAM.

  1. Development of Solid State NMR Methods for the Structural Characterization of Membrane Proteins: Applications to Understand Multiple Sclerosis

    Energy Technology Data Exchange (ETDEWEB)

    Cosman, M; Tran, A T; Ulloa, J; Maxwell, R S

    2003-03-04

    Multiple sclerosis (MS) is a relapsing-remitting disorder of the central nervous system that results in the loss of the myelin sheaths insulating nerve fibers (axons). Strong evidence suggests that MS is an autoimmune disease mediated by T-cell and antibody responses against myelin antigens. Myelin oligodendrocyte glycoprotein (MOG) is a 26 kD to 28 kD an integral membrane protein of the central nervous system implicated as a target for autoaggressive antibodies in MS. To date, the conformation of MOG in association with the myelin membrane is unknown and the exact nature of the interactions between this protein and disease-inducing immune responses have not been determined. Since membrane associated proteins are typically characterized by decreased correlation times, solution state NMR methodologies are often impracticable. Membrane proteins are also often difficult to crystallize for X-ray diffraction studies, Consequently, there is an urgent need to develop new structure characterization tools for this important class of biomolecules. The research described here overviews the initial stages of our effort to develop an integrated, NMR based approach to structural studies of MOG over the many structural domains it is postulated to posses. The structural knowledge gained about this important MS antigen in its native environment will contribute significantly to our understanding of its function in vivo. This project will also aid in the development of therapeutics to inhibit the antigedantibody interaction and thus prevent demyelination in MS patients.

  2. Representational Machines

    DEFF Research Database (Denmark)

    Petersson, Dag; Dahlgren, Anna; Vestberg, Nina Lager

    Photography not only represents space. Space is produced photographically. Since its inception in the 19th century, photography has brought to light a vast array of represented subjects. Always situated in some spatial order, photographic representations have been operatively underpinned by social...... to the enterprises of the medium. This is the subject of Representational Machines: How photography enlists the workings of institutional technologies in search of establishing new iconic and social spaces. Together, the contributions to this edited volume span historical epochs, social environments, technological......, technical, and institutional mechanisms. Geographically, bodily, and geometrically, the camera has positioned its subjects in social structures and hierarchies, in recognizable localities, and in iconic depth constructions which, although they show remarkable variation, nevertheless belong specifically...

  3. A generalized wavelet extrema representation

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Jian; Lades, M.

    1995-10-01

    The wavelet extrema representation originated by Stephane Mallat is a unique framework for low-level and intermediate-level (feature) processing. In this paper, we present a new form of wavelet extrema representation generalizing Mallat`s original work. The generalized wavelet extrema representation is a feature-based multiscale representation. For a particular choice of wavelet, our scheme can be interpreted as representing a signal or image by its edges, and peaks and valleys at multiple scales. Such a representation is shown to be stable -- the original signal or image can be reconstructed with very good quality. It is further shown that a signal or image can be modeled as piecewise monotonic, with all turning points between monotonic segments given by the wavelet extrema. A new projection operator is introduced to enforce piecewise inonotonicity of a signal in its reconstruction. This leads to an enhancement to previously developed algorithms in preventing artifacts in reconstructed signal.

  4. Conceptions of Knowledge in Research on Students' Understanding of the Greenhouse Effect: Methodological Positions and Their Consequences for Representations of Knowing

    Science.gov (United States)

    Jakobsson, Anders; Makitalo, Asa; Saljo, Roger

    2009-01-01

    Much of the research on students' understanding of the greenhouse effect and global warming reports poor results. Students are claimed to hold misconceptions and naive beliefs, and the impact of teaching on their conceptions is also low. In the present study, these results are called into question, and it is argued that they may to a large extent…

  5. Supply chain management: a framework of understanding

    OpenAIRE

    Du Toit, Deirdre; Vlok, Pieter-Jan

    2014-01-01

    The topic of supply chain management (SCM) is complex to understand because it encompasses many different flows of activities, components, functions, and role-players. The literature is scattered across multiple functions, varies in scope, and is often confined to certain elements within SCM. This article aims to provide a literature overview of SCM. It is explained with the aid of a newly-developed framework of understanding that offers a graphical representation of the term. It unifies and ...

  6. On Transitions between Representations: The Role of Contextual Reasoning in Calculus Problem Solving

    Science.gov (United States)

    Zazkis, Dov

    2016-01-01

    This article argues for a shift in how researchers discuss and examine students' uses and understandings of multiple representations within a calculus context. An extension of Zazkis, Dubinsky, and Dautermann's (1996) visualization/analysis framework to include contextual reasoning is proposed. Several examples that detail transitions between…

  7. Regulating Multiple Variables To Understand the Nucleation and Growth and Transformation of PbS Nanocrystal Superlattices.

    Science.gov (United States)

    Wang, Zhongwu; Bian, Kaifu; Nagaoka, Yasutaka; Fan, Hongyou; Cao, Y Charles

    2017-10-18

    Nanocrystals (NCs) can self-assemble into ordered superlattices with collective properties, but the ability for controlling NC assembly remains poorly understandable toward achievement of desired superlattice. This work regulates several key variables of PbS NC assembly (e.g., NC concentration and solubility, solvent type, evaporation rate, seed mediation and thermal treatment), and thoroughly exploits the nucleation and growth as well as subsequent superlattice transformation of NC assembles and underneath mechanisms. PbS NCs in toluene self-assemble into a single face-centered-cubic (fcc) and body-centered-cubic (bcc) superlattice, respectively, at concentrations ≤17.5 and ≥70 mg/mL, but an intermediate concentration between them causes the coexistence of the two superlattices. Differently, NCs in hexane or chloroform self-assemble into only a single bcc superlattice. Distinct controls of NC assembly in solvent with variable concentrations confirm the NC concentration/solubility mediated nucleation and growth of superlattice, in which an evaporation-induced local gradient of NC concentration causes simultaneous nucleation of the two superlattices. The observation for the dense packing planes of NCs in fast growing fcc rather than bcc reveals the difference of entropic driving forces responsible for the two distinct superlattices. Decelerating the solvent evaporation does not amend the superlattice symmetry, but improves the superlattice crystallinity. In addition to shrinking the superlattice volume, thermal treatment also transforms the bcc to an fcc superlattice at 175 °C. Through a seed-meditated growth, the concentration-dependent superlattice does not change lattice symmetry over the course of continuous growth, whereas the newly nucleated secondary small nuclei through a concentration change have relatively higher surface energy and quickly dissolve in solution, providing additional NC sources for the ripening of the primarily nucleated larger and

  8. Development of the Bonding Representations Inventory to Identify Student Misconceptions about Covalent and Ionic Bonding Representations

    Science.gov (United States)

    Luxford, Cynthia J.; Bretz, Stacey Lowery

    2014-01-01

    Teachers use multiple representations to communicate the concepts of bonding, including Lewis structures, formulas, space-filling models, and 3D manipulatives. As students learn to interpret these multiple representations, they may develop misconceptions that can create problems in further learning of chemistry. Interviews were conducted with 28…

  9. Measuring University students' understanding of the greenhouse effect - a comparison of multiple-choice, short answer and concept sketch assessment tools with respect to students' mental models

    Science.gov (United States)

    Gold, A. U.; Harris, S. E.

    2013-12-01

    The greenhouse effect comes up in most discussions about climate and is a key concept related to climate change. Existing studies have shown that students and adults alike lack a detailed understanding of this important concept or might hold misconceptions. We studied the effectiveness of different interventions on University-level students' understanding of the greenhouse effect. Introductory level science students were tested for their pre-knowledge of the greenhouse effect using validated multiple-choice questions, short answers and concept sketches. All students participated in a common lesson about the greenhouse effect and were then randomly assigned to one of two lab groups. One group explored an existing simulation about the greenhouse effect (PhET-lesson) and the other group worked with absorption spectra of different greenhouse gases (Data-lesson) to deepen the understanding of the greenhouse effect. All students completed the same assessment including multiple choice, short answers and concept sketches after participation in their lab lesson. 164 students completed all the assessments, 76 completed the PhET lesson and 77 completed the data lesson. 11 students missed the contrasting lesson. In this presentation we show the comparison between the multiple-choice questions, short answer questions and the concept sketches of students. We explore how well each of these assessment types represents student's knowledge. We also identify items that are indicators of the level of understanding of the greenhouse effect as measured in correspondence of student answers to an expert mental model and expert responses. Preliminary data analysis shows that student who produce concept sketch drawings that come close to expert drawings also choose correct multiple-choice answers. However, correct multiple-choice answers are not necessarily an indicator that a student produces an expert-like correlating concept sketch items. Multiple-choice questions that require detailed

  10. Paying the price for body evolution: The role of evolution in disorders of body representation.

    Science.gov (United States)

    Magnani, Francesca G; Sedda, Anna

    2017-01-01

    Since its beginning, research about cognitive representation of our bodies has debated over multiple representations models. Furthermore, recent years have seen a rise in the study of body representation disorders and related impairments. However, why human beings manifest so many deficits is still a mystery. Considering human evolution, frontal brain regions are well known for their changes in dimensions and connections. Less known is that parietal and temporal lobes encountered similar changes. These areas, especially in the right hemisphere, are crucial for body representation. Our hypothesis is that evolution of these areas determined a more varied and widespread cross wiring between the temporal and parietal lobes, increasing their communication pathways and their reciprocal influence. As such, these connections could lead to an increased probability of interconnected body and emotional disorders in humans. The prediction of this hypothesis is that all body representation disorders have an associated emotional component and vice versa. Evidence supporting the interconnection between emotional and body representation disorders derives from psychiatric diseases such as eating disorders. This hypothesis opens up new directions to understand body representation and points towards innovative solutions for the clinical treatments of body representation/emotional impairments. Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. An Evaluation of a Teaching Intervention to Promote Students' Ability to Use Multiple Levels of Representation when Describing and Explaining Chemical Reactions

    Science.gov (United States)

    Chandrasegaran, A. L.; Treagust, David F.; Mocerino, Mauro

    2008-01-01

    Students are generally known to memorise and regurgitate chemical equations without sufficient understanding of the changes that occur at the particulate level. In addition, they often fail to recognise the significance of the symbols and formulas that are used to represent chemical reactions. This article describes an evaluation of the ability of…

  12. The Importance of Multiple Representations of Mathematical Problems: Evidence from Chinese Preservice Elementary Teachers' Analysis of a Learning Goal

    Science.gov (United States)

    Kang, Rui; Liu, Di

    2018-01-01

    This article describes a study of how Chinese preservice teachers unpacked a learning goal pertaining to adding fractions and understanding the concepts underlying the operation. Based on work in the USA by Morris, Hiebert, and Spizter ("Journal for Research in Mathematics Education," 40(5), 491-529, 2009), 50 Chinese preservice teachers…

  13. Student difficulties regarding symbolic and graphical representations of vector fields

    Directory of Open Access Journals (Sweden)

    Laurens Bollen

    2017-08-01

    Full Text Available The ability to switch between various representations is an invaluable problem-solving skill in physics. In addition, research has shown that using multiple representations can greatly enhance a person’s understanding of mathematical and physical concepts. This paper describes a study of student difficulties regarding interpreting, constructing, and switching between representations of vector fields, using both qualitative and quantitative methods. We first identified to what extent students are fluent with the use of field vector plots, field line diagrams, and symbolic expressions of vector fields by conducting individual student interviews and analyzing in-class student activities. Based on those findings, we designed the Vector Field Representations test, a free response assessment tool that has been given to 196 second- and third-year physics, mathematics, and engineering students from four different universities. From the obtained results we gained a comprehensive overview of typical errors that students make when switching between vector field representations. In addition, the study allowed us to determine the relative prevalence of the observed difficulties. Although the results varied greatly between institutions, a general trend revealed that many students struggle with vector addition, fail to recognize the field line density as an indication of the magnitude of the field, confuse characteristics of field lines and equipotential lines, and do not choose the appropriate coordinate system when writing out mathematical expressions of vector fields.

  14. Student difficulties regarding symbolic and graphical representations of vector fields

    Science.gov (United States)

    Bollen, Laurens; van Kampen, Paul; Baily, Charles; Kelly, Mossy; De Cock, Mieke

    2017-12-01

    The ability to switch between various representations is an invaluable problem-solving skill in physics. In addition, research has shown that using multiple representations can greatly enhance a person's understanding of mathematical and physical concepts. This paper describes a study of student difficulties regarding interpreting, constructing, and switching between representations of vector fields, using both qualitative and quantitative methods. We first identified to what extent students are fluent with the use of field vector plots, field line diagrams, and symbolic expressions of vector fields by conducting individual student interviews and analyzing in-class student activities. Based on those findings, we designed the Vector Field Representations test, a free response assessment tool that has been given to 196 second- and third-year physics, mathematics, and engineering students from four different universities. From the obtained results we gained a comprehensive overview of typical errors that students make when switching between vector field representations. In addition, the study allowed us to determine the relative prevalence of the observed difficulties. Although the results varied greatly between institutions, a general trend revealed that many students struggle with vector addition, fail to recognize the field line density as an indication of the magnitude of the field, confuse characteristics of field lines and equipotential lines, and do not choose the appropriate coordinate system when writing out mathematical expressions of vector fields.

  15. Territories and music territorialities: a representation of places and dailies

    Directory of Open Access Journals (Sweden)

    Lucas Labigalini Fuini

    2014-04-01

    Full Text Available In this article we will seek to understand the contemporary territorialities as conditions and repercussions of globalization, expressed in landscapes and forms-content appearing in musical lyrics. In this sense, our research hypothesis is that musical lyrics, such as case studies and visions about the places, is an important element for understanding the dynamics of deterritorialization and reterritorialization in the current period and that manifest themselves through multiple microterritorialities The territorialities in several scales, can be seen as the individual and collective representations of time and space, bringing in its essence the symbolic elements, identity and the day-by -day of the places, the music is one of these elements of conflicts, territorial uses and practices representation.

  16. Understanding cognitive dysfunction in multiple sclerosis: integrating a first-person perspective with neuropsychological testing, neuroimaging, and cognitive neuroscience research.

    Science.gov (United States)

    Courtney, Susan M

    2011-12-01

    This paper gives perspectives on a companion article, the case history of a professional writer who has multiple sclerosis. The patient's first-person account of her illness is combined with clinical summaries about her care. The discussion of this case illustrates the value of combining such subjective and objective reports in evaluating a patient. Furthermore, considering these reports in the context of current research findings on the organization and function of cognitive neural systems can shed light on patients' seemingly contradictory clinical findings. For this patient, a deficit in the ability to select the most important information to achieve her current goals reflected her neuropsychological test results and neuroradiologic findings, and helped to explain her difficulties with her job and her activities of daily living. Because the patient's cognitive impairments have been her primary manifestations of multiple sclerosis, she illustrates the importance of physicians attending to and helping patients manage their cognitive deficits.

  17. Understanding Confidence Intervals With Visual Representations

    OpenAIRE

    Navruz, Bilgin; Delen, Erhan

    2014-01-01

    In the present paper, we showed how confidence intervals (CIs) are valuable and useful in research studies when they are used in the correct form with correct interpretations. The sixth edition of the APA (2010) Publication Manual strongly recommended reporting CIs in research studies, and it was described as “the best reporting strategy” (p. 34). Misconceptions and correct interpretations of CIs were presented from several textbooks. In addition, limitations of the null hypothesis statistica...

  18. Understanding Selective Downregulation of c-Myc Expression through Inhibition of General Transcription Regulators in Multiple Myeloma

    Science.gov (United States)

    2015-06-01

    Health. Conferences: During this reporting period, this work was presented at conference poster proceedings at the Keystone Symposium on Epigenetics and...tissues from different species . These resources empower our understanding of the complex cartography of the human regulatory landscape, provide

  19. Variation partitioning of diatom species data matrices: Understanding the influence of multiple factors on benthic diatom communities in tropical streams

    Energy Technology Data Exchange (ETDEWEB)

    Bere, Taurai, E-mail: tbere2015@gmail.com; Mangadze, Tinotenda; Mwedzi, Tongai

    2016-10-01

    Elucidating the confounding influence of multiple environmental factors on benthic diatom communities is important in developing water quality predictive models for better guidance of stream management efforts. The objective of this study was to explore the relative impact of metal pollution and hydromorphological alterations in, addition to nutrient enrichment and organic pollution, on diatom taxonomic composition with the view to improve stream diatom-based water quality inference models. Samples were collected twice at 20 sampling stations in the tropical Manyame Catchment, Zimbabwe. Diatom, macroinvertebrate communities and environmental factors were sampled and analysed. The variations in diatom community composition explained by different categories of environmental factors were analysed using canonical correspondence analysis using variance partitioning (partial CCA). The following variations were explained by the different predictor matrices: nutrient levels and organic pollution - 10.4%, metal pollution - 8.3% and hydromorphological factors - 7.9%. Thus, factors other than nutrient levels and organic pollution explain additional significant variation in these diatom communities. Development of diatom-based stream water quality inference models that incorporate metal pollution and hydromorphological alterations, where these are key issues, is thus deemed necessary. - Highlights: • Confounding influences of multiple environmental factors on diatom communities are elucidated. • Variation explained: nutrients + organic pollution - 10.4%, metals - 8.3% and hydromorphological factors - 7.9%. • Calibration of existing or development of new indices may be necessary.

  20. "Always looking for a new balance": toward an understanding of what it takes to continue working while being diagnosed with relapsing-remitting multiple sclerosis.

    Science.gov (United States)

    Meide, Hanneke van der; Gorp, Dennis van; van der Hiele, Karin; Visser, Leo

    2017-06-22

    The aim of this study was to gain insight into the meaning of work in the everyday lives of people with relapsing-remitting multiple sclerosis, and the barriers and facilitators to staying in work. Nineteen employed adults diagnosed with relapsing-remitting multiple sclerosis participated in narrative interviews. All interviews were transcribed and coded for thematic analysis. For people with relapsing-remitting multiple sclerosis, continuing to work was a precarious balancing act. Five themes influenced this balance: becoming familiar with the disease, adjusting expectations, having an understanding and realistic line manager, seeing work as meaningful life activity and strategic considerations. People receiving a diagnosis of relapsing-remitting multiple sclerosis have to refamiliarize themselves with their own body in a meaningful way to be able to continue their work. Rehabilitation professionals can support them herein by taking into account not merely functional capabilities but also identity aspects of the body. Medication that stabilizes symptoms supports making the necessary adjustments. A trusting relationship with the line manager is vital for this adaptation process. Additionally, a match between being adequately challenged by work, while still having the capacity to meet those work demands, is needed, as is long-term financial stability. Implications for rehabilitation Rehabilitation professionals can support employees with relapsing-remitting multiple sclerosis by taking into account not merely functional capabilities but also identity aspects of the body. A trusting relationship with the line manager, including a timely disclosure of the diagnosis, is vital for people with relapsing-remitting multiple sclerosis to remain at work. For people with relapsing-remitting multiple sclerosis, there is a delicate balance between being adequately challenged by work while still having the capacity to meet work demands.

  1. Understanding the positive benefit:risk profile of alemtuzumab in relapsing multiple sclerosis: perspectives from the Alemtuzumab Clinical Development Program

    Directory of Open Access Journals (Sweden)

    Havrdova E

    2017-10-01

    Full Text Available Eva Havrdova,1 Jeffrey A Cohen,2 Dana Horakova,1 Ivana Kovarova,1 Eva Meluzinova3 1Department of Neurology and Center of Clinical Neuroscience, First Faculty of Medicine, Charles University and General University Hospital in Prague, Prague, Czech Republic; 2Neurological Institute, Cleveland Clinic, Cleveland, OH, USA; 3Department of Neurology, Second Faculty of Medicine, Charles University, Motol University Hospital, Prague, Czech Republic Abstract: The introduction of high-efficacy therapies for relapsing–remitting multiple sclerosis has driven re-evaluation of treatment goals and benefit:risk considerations in treatment choice. In the alemtuzumab Phase II and III clinical trials, patients treated with alemtuzumab 12 mg versus subcutaneous interferon beta-1a demonstrated significantly reduced annualized relapse rates and improved magnetic resonance imaging outcomes, and were significantly more likely to achieve no evidence of disease activity and reduction in brain volume loss. In two of the studies, alemtuzumab-treated patients had a significantly reduced risk of 6-month confirmed disease worsening, compared with subcutaneous interferon beta-1a. Benefits were maintained throughout 5 years, with a majority of patients receiving no alemtuzumab retreatment or other disease-modifying therapy. Trial results support alemtuzumab’s manageable, consistent safety profile in relapsing–remitting multiple sclerosis. Infusion-associated reactions, the most frequent adverse events (AEs, can be minimized by corticosteroid pretreatment, monitoring, and symptomatic management. Other AEs include infections and autoimmune events. Oral anti-herpes prophylaxis should be initiated on the first day of each alemtuzumab treatment course and continued according to local guidelines. Overall cancer risk was lower in the alemtuzumab clinical trials than in a reference population; however, continuing surveillance will determine if alemtuzumab may be associated with

  2. A multiple-cue learning approach as the basis for understanding and improving soccer referees' decision making.

    Science.gov (United States)

    Plessner, Henning; Schweizer, Geoffrey; Brand, Ralf; O'Hare, David

    2009-01-01

    A significant proportion of all referee decisions during a soccer match are about fouls and misconduct. We argue that most of these decisions can be considered as a perceptual-categorization task in which the referee has to categorize a set of features into two discrete classes (foul/no-foul). Due to the dynamic nature of tackling situations in football, these features share a probabilistic rather that a deterministic relationship with the decision criteria. Accordingly, these processes can be studied on the basis of a multiple-cue learning framework as proposed by Brunswick (1955), which focuses among others on how people learn from repeated exposure to probabilistic information. Such learning processes have been studied on a wide range of tasks, but until now not (to our knowledge) in the area of judging sport performance. We suggest that decision accuracy of referees can be improved by creating a learning environment that fits the requirements of this theoretical perspective.

  3. Media Representation of Teachers across Five Countries

    Science.gov (United States)

    Alhamdan, Bandar; Al-Saadi, Khalid; Baroutsis, Aspa; Du Plessis, Anna; Hamid, Obaidul M.; Honan, Eileen

    2014-01-01

    This paper reports on an investigation into the representation of teachers in newspapers in five countries. An innovative methodology was used to develop a method of inquiry that supports a deeper understanding of media representations of teachers which can also be used by other researchers in comparative education. The paper explores relevant…

  4. Current Understanding on the Role of Standard and Immunoproteasomes in Inflammatory/Immunological Pathways of Multiple Sclerosis

    Directory of Open Access Journals (Sweden)

    Elena Bellavista

    2014-01-01

    Full Text Available The ubiquitin-proteasome system is the major intracellular molecular machinery for protein degradation and maintenance of protein homeostasis in most human cells. As ubiquitin-proteasome system plays a critical role in the regulation of the immune system, it might also influence the development and progression of multiple sclerosis (MS. Both ex vivo analyses and animal models suggest that activity and composition of ubiquitin-proteasome system are altered in MS. Proteasome isoforms endowed of immunosubunits may affect the functionality of different cell types such as CD8+ and CD4+ T cells and B cells as well as neurons during MS development. Furthermore, the study of proteasome-related biomarkers, such as proteasome antibodies and circulating proteasomes, may represent a field of interest in MS. Proteasome inhibitors are already used as treatment for cancer and the recent development of inhibitors selective for immunoproteasome subunits may soon represent novel therapeutic approaches to the different forms of MS. In this review we describe the current knowledge on the potential role of proteasomes in MS and discuss the pro et contra of possible therapies for MS targeting proteasome isoforms.

  5. Men, multiple sexual partners, and young adults' sexual relationships: understanding the role of gender in the study of risk.

    Science.gov (United States)

    O'Sullivan, Lucia F; Hoffman, Susie; Harrison, Abigail; Dolezal, Curtis

    2006-07-01

    Heterosexual transmission of HIV and other sexually transmitted infections has become a primary health concern worldwide. Gender roles for heterosexual interactions appear to sanction men's sexual risk-taking, especially the pursuit of multiple sexual partners. Using measures developed in this study, the current study assessed the associations between men's and women's relationship attitudes and experiences and their sexual risk encounters. Participants were 104 men and 103 women (18-24 years) from a large, urban college located in a high HIV risk neighborhood of New York City. All completed a survey assessing HIV risk and the battery of relationship measures assessing traditional sexual roles, sexual conflicts, significance of sex, relationship investment, need for relationship, and unwanted sex. For men, greater sexual conflict in their primary relationships was associated with more sexual partners and fewer unprotected vaginal intercourse encounters with a primary partner and across sex partners overall. In addition, men's endorsement of more traditional sexual roles and lower relationship investment were associated with higher numbers of sexual partners. Among women, compliance with men to engage in unwanted sex was associated with higher levels of participation in unprotected sex. For both men and women, greater significance given to sex in a relationship was associated with fewer extradyadic partners. This study demonstrates the utility of measures of relationship attitudes and experiences to characterize sexual risk, especially among men. Findings are discussed in terms of implications for prevention program targeting young urban adults.

  6. [Time perceptions and representations].

    Science.gov (United States)

    Tordjman, S

    2015-09-01

    fundamentally lacking in their physiological development due to possibly altered circadian rhythms, including arhythmy and asynchrony. Time measurement, based on the repetition of discontinuity at regular intervals, involves also a spatial representation. It is our own trajectory through space-time, and thus our own motion, including the physiological process of aging, that affords us a representation of the passing of time, just as the countryside seems to be moving past us when we travel in a vehicle. Chinese and Indian societies actually have circular representations of time, and linear representations of time and its trajectory through space-time are currently a feature of Western societies. Circular time is collective time, and its metaphysical representations go beyond the life of a single individual, referring to the cyclical, or at least nonlinear, nature of time. Linear time is individual time, in that it refers to the scale of a person's lifetime, and it is physically represented by an arrow flying ineluctably from the past to the future. An intermediate concept can be proposed that acknowledges the existence of linear time involving various arrows of time corresponding to different lifespans (human, animal, plant, planet lifespans, etc.). In fact, the very notion of time would depend on the trajectory of each arrow of time, like shooting stars in the sky with different trajectory lengths which would define different time scales. The time scale of these various lifespans are very different (for example, a few decades for humans and a few days or hours for insects). It would not make sense to try to understand the passage of time experienced by an insect which may live only a few hours based on a human time scale. One hour in an insect's life cannot be compared to one experienced by a human. Yet again, it appears that there is a coexistence of different clocks based here on different lifespans. Finally, the evolution of our society focused on the present moment and

  7. Understanding Snow Depth Variability with Respect to the Canopy in Multiple Climates Using Airborne LiDAR

    Science.gov (United States)

    Currier, W. R.; Giulia, M.; Pflug, J. M.; Jonas, T.; Jessica, L.

    2017-12-01

    Snow depth within a typical hydrologic model grid cell (150 m or 1 km) can vary from 0.5 meters to 6 meters, or more. This variability is driven by the meteorological conditions throughout the winter as well as the forest architecture. To better understand this variability, we used airborne LiDAR from Olympic National Park, WA, Yosemite National Park, CA, Jemez Caldera, NM, and Niwot Ridge, CO to determine unique spatial patterns of snow depth in forested regions. Specifically, we compared snow depth distributions along north facing forest edges and south facing forest edges to those in the open or directly under the canopy. When categorizing the north facing and south facing edges based on distance from the canopy, distances relative to tree height, and distances relative to the fraction of the sky that is visible (sky view factor) we found unique snow depth patterns for each of these regions. In all regions besides Olympic National Park, WA, north facing edges contained more snow than open areas, forested areas, or along the south facing edges. These snow distributions were relatively consistent regardless of the metric used to define the forest edge and the size of the domain (150 m through 1 km). The absence of the forest edge effect in Olympic National Park was attributed to the meteorological data and climate conditions, which showed significantly less incoming shortwave radiation and more incoming longwave radiation. Furthermore, this study evaluated the effect that wind speed and direction have on the spatial distribution of snow depth.

  8. Translating between Representations in a Social Context: A Study of Undergraduate Science Students' Representational Fluency

    Science.gov (United States)

    Nichols, Kim; Ranasinghe, Muditha; Hanan, Jim

    2013-01-01

    Interacting with and translating across multiple representations is an essential characteristic of expertise and representational fluency. In this study, we explored the effect of interacting with and translating between representations in a computer simulation or in a paper-based assignment on scientific accuracy of undergraduate science…

  9. Monoclonal gammopathy of undetermined significance and smoldering multiple myeloma: a review of the current understanding of epidemiology, biology, risk stratification, and management of myeloma precursor disease.

    Science.gov (United States)

    Agarwal, Amit; Ghobrial, Irene M

    2013-03-01

    The term monoclonal gammopathy of undetermined significance (MGUS) was coined in 1978. The recent advances in our knowledge about MGUS and smoldering multiple myeloma (SMM) have helped us better understand the pathogenesis of myeloma. It seems that myeloma evolves from a precursor state in almost all cases. We do not completely understand the multistep process from the precursor state to myeloma, but studies like whole genome sequencing continue to improve our understanding of this process. The process of transformation may not be linear acquisition of changes, but rather a branched heterogeneous process. Clinical features that are prognostic of rapid transformation have been identified, but no specific molecular markers have been identified. Even with recent advances, multiple myeloma remains an incurable disease in the vast majority, and intervening at the precursor state provides a unique opportunity to alter the natural history of the disease. A limitation is that a vast majority of patients with precursor disease, especially low-risk MGUS, will never progress to myeloma in their lifetime, and treating these patients is not only unnecessary but may be potentially harmful. The challenge is to identify a subset of patients with the precursor state that would definitely progress to myeloma and in whom interventions will have a meaningful impact. As our understanding of the molecular and genetic processes improves, these studies will guide the selection of high-risk patients more appropriately and ultimately direct a tailored management strategy to either delay progression to symptomatic myeloma or even "cure" a person at this premalignant stage. ©2012 AACR.

  10. The representations of work-life balance in Canadian newspapers.

    Science.gov (United States)

    Reece, Katherine T; Davis, Jane A; Polatajko, Helene J

    2009-01-01

    Work-life balance has become a topic of increasing interest in the media as well as a concern among working Canadians. Since print media discourse can both reflect and shape societal values, cultural norms and ideals of workers in this country, it is important to understand this representation and its potential influence on the occupational engagement and life transitions of Canadian workers. Articles from four major Canadian newspapers published between 2003 and 2005 were used as data sources to examine the media construction of "work-life balance". Thematic analysis of 100 articles was performed using a modified affinity diagramming process. Representations within the Canadian print media conveyed both themes pertaining to the perceived experiences of imbalance and balance, as well as, a process of life balance. Obtaining balance was portrayed as an ongoing process during which an individual negotiates and sacrifices in an attempt to achieve his or her ideal level of balance. Environmental expectations and individual practices and perceptions were conveyed as reasons for the success or derailment of balance. The representations of work-life balance found in the Canadian print media were predominantly of professionals, focused on the demands of work and family, and did not appear to be a broad representation of the multiple realities that all Canadians face.

  11. New Hamiltonians for loop quantum cosmology with arbitrary spin representations

    Science.gov (United States)

    Ben Achour, Jibril; Brahma, Suddhasattwa; Geiller, Marc

    2017-04-01

    In loop quantum cosmology, one has to make a choice of SU(2) irreducible representation in which to compute holonomies and regularize the curvature of the connection. The systematic choice made in the literature is to work in the fundamental representation, and very little is known about the physics associated with higher spin labels. This constitutes an ambiguity of which the understanding, we believe, is fundamental for connecting loop quantum cosmology to full theories of quantum gravity like loop quantum gravity, its spin foam formulation, or cosmological group field theory. We take a step in this direction by providing here a new closed formula for the Hamiltonian of flat Friedmann-Lemaître-Robertson-Walker models regularized in a representation of arbitrary spin. This expression is furthermore polynomial in the basic variables which correspond to well-defined operators in the quantum theory, takes into account the so-called inverse-volume corrections, and treats in a unified way two different regularization schemes for the curvature. After studying the effective classical dynamics corresponding to single and multiple-spin Hamiltonians, we study the behavior of the critical density when the number of representations is increased and the stability of the difference equations in the quantum theory.

  12. Content-adaptive pyramid representation for 3D object classification

    DEFF Research Database (Denmark)

    Kounalakis, Tsampikos; Boulgouris, Nikolaos; Triantafyllidis, Georgios

    2016-01-01

    In this paper we introduce a novel representation for the classification of 3D images. Unlike most current approaches, our representation is not based on a fixed pyramid but adapts to image content and uses image regions instead of rectangular pyramid scales. Image characteristics, such as depth...... and color, are used for defining regions within images. Multiple region scales are formed in order to construct the proposed pyramid image representation. The proposed method achieves excellent results in comparison to conventional representations....

  13. Representation as the representation of experience

    NARCIS (Netherlands)

    Ankersmit, FR

    This essay deals, mainly, with the notion of representation. Representation is associated with texts and, as such, is contrasted to the true singular statement. It is argued that the relationship between the text and what the text represents can never be modeled on the relationship between the true

  14. CLASIFICACION MÚLTIPLE DE ITEMS Y LAS REPRESENTACIONES SOCIALES SOBRE AMBIENTE EN PROFESORES RURALES (MULTIPLE ITEM CLASSIFICATION TECHNIQUE AND TEACHERS’ SOCIAL REPRESENTATIONS CONCERNING THE ENVIRONMENT IN RURAL AREAS

    Directory of Open Access Journals (Sweden)

    Obregoso Rodríguez Yolima

    2010-08-01

    rural teachers’ groups in Bogota D.C., Colombia. It was developed in two Rural Institutions of the District: Gimnasio del Campo Juan de la Cruz Varela (Sumapaz and Colegio Rural Quiba Alta (Ciudad Bolívar. It was used a type interview, half-structured, developed through Multiple Items Classification (MIC technique. The analysis was made through previous categories, drawn from the Sauvé and Orellana’s (2002 environmental typologies. By means of that, it was possible to identify common and particular categories held by both groups of teachers. It was identified as a common category environment as resource of living and nature; as particular ones, context, landscape, biosphere, as well as communitarian project, for Sumapaz, system and territory, for Ciudad Bolivar. It was concluded, firstly, that teachers have an analytical tendency concerning the environment; secondly, that there are different representations concerning the environment, in relation to professional occupation, daily life, and context; thirdly, that there are categories convergences, in as much as it was identified environment as subsistence resource and natural resource around teachers. Probably, it would be the reason for teachers having difficulties to interrelate different environmental elements.

  15. The Ability of Young Korean Children to Use Spatial Representations

    Science.gov (United States)

    Kim, Minsung; Bednarz, Robert; Kim, Jaeyil

    2012-01-01

    The National Research Council emphasizes using tools of representation as an essential element of spatial thinking. However, it is debatable at what age the use of spatial representation for spatial thinking skills should begin. This study investigated whether young Korean children possess the potential to understand map-like representation using…

  16. Operational Automatic Remote Sensing Image Understanding Systems: Beyond Geographic Object-Based and Object-Oriented Image Analysis (GEOBIA/GEOOIA. Part 2: Novel system Architecture, Information/Knowledge Representation, Algorithm Design and Implementation

    Directory of Open Access Journals (Sweden)

    Luigi Boschetti

    2012-09-01

    Full Text Available According to literature and despite their commercial success, state-of-the-art two-stage non-iterative geographic object-based image analysis (GEOBIA systems and three-stage iterative geographic object-oriented image analysis (GEOOIA systems, where GEOOIA/GEOBIA, remain affected by a lack of productivity, general consensus and research. To outperform the Quality Indexes of Operativeness (OQIs of existing GEOBIA/GEOOIA systems in compliance with the Quality Assurance Framework for Earth Observation (QA4EO guidelines, this methodological work is split into two parts. Based on an original multi-disciplinary Strengths, Weaknesses, Opportunities and Threats (SWOT analysis of the GEOBIA/GEOOIA approaches, the first part of this work promotes a shift of learning paradigm in the pre-attentive vision first stage of a remote sensing (RS image understanding system (RS-IUS, from sub-symbolic statistical model-based (inductive image segmentation to symbolic physical model-based (deductive image preliminary classification capable of accomplishing image sub-symbolic segmentation and image symbolic pre-classification simultaneously. In the present second part of this work, a novel hybrid (combined deductive and inductive RS-IUS architecture featuring a symbolic deductive pre-attentive vision first stage is proposed and discussed in terms of: (a computational theory (system design, (b information/knowledge representation, (c algorithm design and (d implementation. As proof-of-concept of symbolic physical model-based pre-attentive vision first stage, the spectral knowledge-based, operational, near real-time, multi-sensor, multi-resolution, application-independent Satellite Image Automatic Mapper™ (SIAM™ is selected from existing literature. To the best of these authors’ knowledge, this is the first time a symbolic syntactic inference system, like SIAM™, is made available to the RS community for operational use in a RS-IUS pre-attentive vision first stage

  17. "You've Got to Teach People that Racism Is Wrong and Then They Won't Be Racist": Curricular Representations and Young People&'s Understandings of "Race" and Racism

    Science.gov (United States)

    Bryan, Audrey

    2012-01-01

    This paper critically examines the discursive (mis) representation of "race" and racism in the formal curriculum. Combining qualitative data derived from interviews with 35 young people who were enrolled in a Dublin-based, ethnically diverse secondary school, with a critical discursive analysis of 20 textbooks, the paper explores…

  18. General Chemistry Students' Understanding of the Chemistry Underlying Climate Science and the Development of a Two-Tiered Multiple-Choice Diagnostic Instrument

    Science.gov (United States)

    Versprille, A.; Towns, M.; Mahaffy, P.; Martin, B.; McKenzie, L.; Kirchhoff, M.

    2013-12-01

    As part of the NSF funded Visualizing the Chemistry of Climate Change (VC3) project, we have developed a chemistry of climate science diagnostic instrument for use in general chemistry courses based on twenty-four student interviews. We have based our interview protocol on misconceptions identified in the research literature and the essential principles of climate change outlined in the CCSP document that pertain to chemistry (CCSP, 2009). The undergraduate student interviews elicited their understanding of the greenhouse effect, global warming, climate change, greenhouse gases, climate, and weather, and the findings from these interviews informed and guided the development of the multiple-choice diagnostic instrument. Our analysis and findings from the interviews indicate that students seem to confuse the greenhouse effect, global warming, and the ozone layer and in terms of chemistry concepts, the students lack a particulate level understanding of greenhouse gases causing them to not fully conceptualize the greenhouse effect and climate change. Details of the findings from the interviews, development of diagnostic instrument, and preliminary findings from the full implementation of the diagnostic instrument will be shared.

  19. A qualia representation of cyberspace

    Science.gov (United States)

    Lacey, Timothy H.; Mills, Robert F.; Raines, Richard A.; Oxley, Mark E.; Bauer, Kenneth W.; Rogers, Steven K.

    2008-04-01

    E.C Adam defined Situational Awareness (SA) as "the mental representation and understanding of objects, events, people, system states, interactions, environmental conditions, and other situation-specific factors affecting human performance in complex and dynamic tasks. Stated in lay terms, SA is simply knowing what is going on so you can figure out what to do." We propose a novel idea to assist the human in gaining SA. Our hypothesis is that nature uses qualia as a compression scheme to represent the many concepts encountered in everyday life. Qualia enable humans to quickly come up with SA based on many complex measurements from their sensors, (eyes, ears, taste, touch, memory, etc.), expectations, and experiences. Our ultimate objective is to develop a computer that uses qualia concepts to transform sensor data to assist the human in gaining and maintaining improved SA. However, before any computer can use qualia, we must first define a representation for qualia that can be implemented computationally. This paper will present our representation for qualia. The representation is not simply a hierarchical aggregation of input data. Instead, it is a prediction of what will happen next, derived from computations resulting from sensory inputs and the computational engine of a qualia generator and qualia processor.

  20. Visualizer’s representation in functions

    Science.gov (United States)

    Setyawan, F.; Prahmana, R. C. I.; istiandaru, A.; hendroanto, A.

    2017-12-01

    Students’ understanding of a mathematics objects can be seen by their perspective of a mathematics topic. In other words, the study of a specific case can enrich one’s conceptualization of the general. This study is a descriptive qualitative research. The visualizer’s paperwork is described based on their preference in representing a function. Visualizer’s paperwork and interviews provide opportunities to get additional description about her mathematical conceptions and how her understanding about functions by using representation. Visualizer tends to connect their imagination of a picture and represents it based on her ideas. Visualizer defines functions by its perceptual unit that each elements of the domain connected with exactly one element of the codomain. In modelling graph representation, object imager uses all information in the diagram and represent it in symbol notation. In interpreting functions, object imager prefers diagram representation rather than word situation and symbol representation.

  1. Low dimensional representation of face space by face-selective inferior temporal neurons.

    Science.gov (United States)

    Salehi, Sina; Dehaqani, Mohammad-Reza A; Esteky, Hossein

    2017-05-01

    The representation of visual objects in primate brain is distributed and multiple neurons are involved in encoding each object. One way to understand the neural basis of object representation is to estimate the number of neural dimensions that are needed for veridical representation of object categories. In this study, the characteristics of the match between physical-shape and neural representational spaces in monkey inferior temporal (IT) cortex were evaluated. Specifically, we examined how the number of neural dimensions, stimulus behavioral saliency and stimulus category selectivity of neurons affected the correlation between shape and neural representational spaces in IT cortex. Single-unit recordings from monkey IT cortex revealed that there was a significant match between face space and its neural representation at lower neural dimensions, whereas the optimal match for the non-face objects was observed at higher neural dimensions. There was a statistically significant match between the face and neural spaces only in the face-selective neurons, whereas a significant match was observed for non-face objects in all neurons regardless of their category selectivity. Interestingly, the face neurons showed a higher match for the non-face objects than for the faces at higher neural dimensions. The optimal representation of face space in the responses of the face neurons was a low dimensional map that emerged early (~150 ms post-stimulus onset) and was followed by a high dimensional and relatively late (~300 ms) map for the non-face stimuli. These results support a multiplexing function for the face neurons in the representation of very similar shape spaces, but with different dimensionality and timing scales. © 2017 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

  2. Embedded data representations

    DEFF Research Database (Denmark)

    Willett, Wesley; Jansen, Yvonne; Dragicevic, Pierre

    2017-01-01

    We introduce embedded data representations, the use of visual and physical representations of data that are deeply integrated with the physical spaces, objects, and entities to which the data refers. Technologies like lightweight wireless displays, mixed reality hardware, and autonomous vehicles ......-situated, situated, and embedded data displays, including both visualizations and physicalizations. Based on our observations, we identify a variety of design challenges for embedded data representation, and suggest opportunities for future research and applications....

  3. XML-BASED REPRESENTATION

    Energy Technology Data Exchange (ETDEWEB)

    R. KELSEY

    2001-02-01

    For focused applications with limited user and use application communities, XML can be the right choice for representation. It is easy to use, maintain, and extend and enjoys wide support in commercial and research sectors. When the knowledge and information to be represented is object-based and use of that knowledge and information is a high priority, then XML-based representation should be considered. This paper discusses some of the issues involved in using XML-based representation and presents an example application that successfully uses an XML-based representation.

  4. Distinguishing Representations as Origin and Representations as Input: Roles for Individual Cells

    Directory of Open Access Journals (Sweden)

    Jonathan C.W. Edwards

    2016-09-01

    input interaction between signals and consumer. The acceptance of this necessity provides a basis for resolving the problem that representations appear both as distributed (representation-as-origin and local (representation-as-input. The key implications are that representations in brain are massively multiple both in series and in parallel, and that individual cells play specific semantic roles. These roles are discussed in relation to traditional concepts of ‘gnostic’ cell types.

  5. Understanding nurses' dual practice: a scoping review of what we know and what we still need to ask on nurses holding multiple jobs.

    Science.gov (United States)

    Russo, Giuliano; Fronteira, Inês; Jesus, Tiago Silva; Buchan, James

    2018-02-22

    Mounting evidence suggests that holding multiple concurrent jobs in public and private (dual practice) is common among health workers in low- as well as high-income countries. Nurses are world's largest health professional workforce and a critical resource for achieving Universal Health Coverage. Nonetheless, little is known about nurses' engagement with dual practice. We conducted a scoping review of the literature on nurses' dual practice with the objective of generating hypotheses on its nature and consequences, and define a research agenda on the phenomenon. The Arksey and O'Malley's methodological steps were followed to develop the research questions, identify relevant studies, include/exclude studies, extract the data, and report the findings. PRISMA guidelines were additionally used to conduct the review and report on results. Of the initial 194 records identified, a total of 35 met the inclusion criteria for nurses' dual practice; the vast majority (65%) were peer-reviewed publications, followed by nursing magazine publications (19%), reports, and doctoral dissertations. Twenty publications focused on high-income countries, 16 on low- or middle-income ones, and two had a multi country perspective. Although holding multiple jobs not always amounted to dual practice, several ways were found for public-sector nurses to engage concomitantly in public and private employments, in regulated as well as in informal, casual fashions. Some of these forms were reported as particularly prevalent, from over 50% in Australia, Canada, and the UK, to 28% in South Africa. The opportunity to increase a meagre salary, but also a dissatisfaction with the main job and the flexibility offered by multiple job-holding arrangements, were among the reported reasons for engaging in these practices. Limited and mostly circumstantial evidence exists on nurses' dual practice, with the few existing studies suggesting that the phenomenon is likely to be very common and carry  implications

  6. Issues relating to representation of multiple conductors for a conductor equivalent: proposal for a model that takes into account the current distribution among semiconductor beam; Aspectos referentes a representaco de condutores multiplos por um condutor equivalente: proposta de um modelo que leva em conta a distribuicao da corrente entre os subcondutores do feixe

    Energy Technology Data Exchange (ETDEWEB)

    Kurokawa, S.; Costa, E.C.M.; Prado, A.J.; Bovolato, L.F. [Universidade Estadual Paulista (FEIS/UNESP), Ilha Solteira, SP (Brazil). Fac. de Engenharia], Emails: kurokawa@dee.feis.unesp.br, edumarquescosta@hotmail.com, afonsojp@uol.com.br, bovolato@dee.feis.unesp.br; Pissolato, J. [Universidade Estadual de Campinas (FEEC/UNICAMP), SP (Brazil). Fac. de Engenharia Eletrica e de Computacao], E-mail: pisso@dsce.fee.unicamp.br

    2009-07-01

    In a traditional multiple conductors, the sub-conductors are identical and are separated by a small distance. Based on this fact it is possible to say that currents that run through the sub-conductors are approximately equal, allowing the representation of a multiple conductor as a single conductor whose radius is equal to the geometric mean radius of the sub-conductors that is in the geometric center of the beam. The possibility of emergence of new configurations to multiple conductors, where is not possible to consider that the current is distributed equally among all sub-conductors, led the authors to propose an alternative method for calculating the parameters of the equivalent conductor taking into account the actual distribution of current between the sub-conductors. The method was applied to a typical beam where sub-conductors are equal and also in a multiple conductor in which the sub-conductors are different.

  7. Combining multiple approaches and optimized data resolution for an improved understanding of stream temperature dynamics of a forested headwater basin in the Southern Appalachians

    Science.gov (United States)

    Belica, L.; Mitasova, H.; Caldwell, P.; McCarter, J. B.; Nelson, S. A. C.

    2017-12-01

    Thermal regimes of forested headwater streams continue to be an area of active research as climatic, hydrologic, and land cover changes can influence water temperature, a key aspect of aquatic ecosystems. Widespread monitoring of stream temperatures have provided an important data source, yielding insights on the temporal and spatial patterns and the underlying processes that influence stream temperature. However, small forested streams remain challenging to model due to the high spatial and temporal variability of stream temperatures and the climatic and hydrologic conditions that drive them. Technological advances and increased computational power continue to provide new tools and measurement methods and have allowed spatially explicit analyses of dynamic natural systems at greater temporal resolutions than previously possible. With the goal of understanding how current stream temperature patterns and processes may respond to changing landcover and hydroclimatoligical conditions, we combined high-resolution, spatially explicit geospatial modeling with deterministic heat flux modeling approaches using data sources that ranged from traditional hydrological and climatological measurements to emerging remote sensing techniques. Initial analyses of stream temperature monitoring data revealed that high temporal resolution (5 minutes) and measurement resolutions (geospatial models of subcanopy solar radiation and channel morphology were used to develop hypotheses and guide field data collection for further heat flux modeling. By integrating multiple approaches and optimizing data resolution for the processes being investigated, small, but ecologically significant differences in stream thermal regimes were revealed. In this case, multi-approach research contributed to the identification of the dominant mechanisms driving stream temperature in the study area and advanced our understanding of the current thermal fluxes and how they may change as environmental conditions

  8. Wigner's Symmetry Representation Theorem

    Indian Academy of Sciences (India)

    IAS Admin

    This article elucidates the important role the no- tion of symmetry has played in physics. It dis- cusses the proof of one of the important theorems of quantum mechanics, viz., Wigner's Symmetry. Representation Theorem. It also shows how the representations of various continuous and dis- crete symmetries follow from the ...

  9. Extensions of tempered representations

    NARCIS (Netherlands)

    Opdam, E.; Solleveld, M.

    2013-01-01

    Let π, π′ be irreducible tempered representations of an affine Hecke algebra H with positive parameters. We compute the higher extension groups Ext nH(π,π′) explicitly in terms of the representations of analytic R-groups corresponding to π and π′. The result has immediate applications to the

  10. Representation and Reference

    NARCIS (Netherlands)

    Ankersmit, F.R.

    2010-01-01

    This essay focuses on the historical text as a whole. It does so by conceiving of the historical text as representation - in the way the we may say of a photo or a painting that it represents the person depicted on it. It is argued that representation cannot be properly understood by modelling it on

  11. Altered Images: the relations between design representation and design practice

    Directory of Open Access Journals (Sweden)

    Susan Keller

    2005-05-01

    Full Text Available As information systems move out of the office into the wider world and are merged with mobile appliances, buildings and even clothing, the representations traditionally used in any one discipline may not be adequate for understanding these new domains. Design representations are ‘ways of seeing and not seeing’. Despite the central role representations play in design, the information systems design community has little understanding of the relation, ideal or actual, between design practice and design representation. This paper reports on an extensive design case study that aims at increasing understanding of the nature and affordances of representations in the design process and argues for the need for information systems as a discipline to open up discussion of the design representations that may be required to effectively design systems that mix traditional IS with disciplines such as industrial design, architecture and fashion design.

  12. Scientific representation and nominalism: an empiricist view

    Directory of Open Access Journals (Sweden)

    Otávio Bueno

    2008-01-01

    Full Text Available http://dx.doi.org/10.5007/1808-1711.2008v12n2p177 Can a constructive empiricist make sense of scientific representation? Usually, a scientific model is an abstract entity (e.g., formulated in set theory, and scientific representation is conceptualized as an intentional relation between scientific models and certain aspects of the world. On this conception, since both the models and the representation relation are abstract, a constructive empiricist, who is not committed to the existence of abstract entities, would be unable to invoke these notions to make sense of scientific representation. In this paper, instead of understanding representation as a relation between abstract entities, I focus on the activity of representing, and argue that it provides a way of making sense of representation within the boundaries of empiricism. The activity of representing doesn’t deal with abstract entities, but with concrete ones, such as inscriptions, templates, and blueprints. In the end, by examining the practice of representing, rather than an artificially reified product—the representation—the constructive empiricist has the resources to make sense of scientific representation in empiricist terms.

  13. Multiple myeloma.

    LENUS (Irish Health Repository)

    Collins, Conor D

    2012-02-01

    Advances in the imaging and treatment of multiple myeloma have occurred over the past decade. This article summarises the current status and highlights how an understanding of both is necessary for optimum management.

  14. Understanding the Relationships between Gender Inequitable Behaviours, Childhood Trauma and Socio-Economic Status in Single and Multiple Perpetrator Rape in Rural South Africa: Structural Equation Modelling.

    Directory of Open Access Journals (Sweden)

    Rachel Jewkes

    Full Text Available Interventions to prevent rape perpetration must be designed to address its drivers. This paper seeks to extend understanding of drivers of single and multiple perpetrator rape (referred to here as SPR and MPR respectively and the relationships between socio-economic status, childhood trauma, peer pressure, other masculine behaviours and rape.1370 young men aged 15 to 26 were interviewed as part of the randomised controlled trial evaluation of Stepping Stones in the rural Eastern Cape. We used multinomial to compare the characteristics of men who reported rape perpetration at baseline. We used structural equation modelling (SEM to examine pathways to rape perpetration.76.1% of young men had never raped, 10.0% had perpetrated SPR and 13.9% MPR. The factors associated with both MPR and SPR (compared to never having raped were indicators of socio-economic status (SES, childhood trauma, sexual coercion by a woman, drug and alcohol use, peer pressure susceptibility, having had transactional sex, multiple sexual partners and being physically violent towards a partner. The SEM showed the relationship between SES and rape perpetration to be mediated by gender inequitable masculinity. It was complex as there was a direct path indicating that SES correlated with the masculinity variable directly such that men of higher SES had more gender inequitable masculinities, and indirect path mediated by peer pressure resistance indicated that the former pertained so long as men lacked peer pressure resistance. Having a higher SES conveyed greater resistance for some men. There was also a path mediated through childhood trauma, such that men of lower SES were more likely to have a higher childhood trauma exposure and this correlated with a higher likelihood of having the gender inequitable masculinity (with or without the mediating effect of peer pressure resistance.Both higher and lower socio-economic status were associated with raping. Prevention of rape

  15. Understanding the Relationships between Gender Inequitable Behaviours, Childhood Trauma and Socio-Economic Status in Single and Multiple Perpetrator Rape in Rural South Africa: Structural Equation Modelling

    Science.gov (United States)

    Jewkes, Rachel; Nduna, Mzikazi; Jama-Shai, Nwabisa; Chirwa, Esnat; Dunkle, Kristin

    2016-01-01

    Background Interventions to prevent rape perpetration must be designed to address its drivers. This paper seeks to extend understanding of drivers of single and multiple perpetrator rape (referred to here as SPR and MPR respectively) and the relationships between socio-economic status, childhood trauma, peer pressure, other masculine behaviours and rape. Method 1370 young men aged 15 to 26 were interviewed as part of the randomised controlled trial evaluation of Stepping Stones in the rural Eastern Cape. We used multinomial to compare the characteristics of men who reported rape perpetration at baseline. We used structural equation modelling (SEM) to examine pathways to rape perpetration. Results 76.1% of young men had never raped, 10.0% had perpetrated SPR and 13.9% MPR. The factors associated with both MPR and SPR (compared to never having raped) were indicators of socio-economic status (SES), childhood trauma, sexual coercion by a woman, drug and alcohol use, peer pressure susceptibility, having had transactional sex, multiple sexual partners and being physically violent towards a partner. The SEM showed the relationship between SES and rape perpetration to be mediated by gender inequitable masculinity. It was complex as there was a direct path indicating that SES correlated with the masculinity variable directly such that men of higher SES had more gender inequitable masculinities, and indirect path mediated by peer pressure resistance indicated that the former pertained so long as men lacked peer pressure resistance. Having a higher SES conveyed greater resistance for some men. There was also a path mediated through childhood trauma, such that men of lower SES were more likely to have a higher childhood trauma exposure and this correlated with a higher likelihood of having the gender inequitable masculinity (with or without the mediating effect of peer pressure resistance). Discussion Both higher and lower socio-economic status were associated with raping

  16. Understanding the Relationships between Gender Inequitable Behaviours, Childhood Trauma and Socio-Economic Status in Single and Multiple Perpetrator Rape in Rural South Africa: Structural Equation Modelling.

    Science.gov (United States)

    Jewkes, Rachel; Nduna, Mzikazi; Jama-Shai, Nwabisa; Chirwa, Esnat; Dunkle, Kristin

    2016-01-01

    Interventions to prevent rape perpetration must be designed to address its drivers. This paper seeks to extend understanding of drivers of single and multiple perpetrator rape (referred to here as SPR and MPR respectively) and the relationships between socio-economic status, childhood trauma, peer pressure, other masculine behaviours and rape. 1370 young men aged 15 to 26 were interviewed as part of the randomised controlled trial evaluation of Stepping Stones in the rural Eastern Cape. We used multinomial to compare the characteristics of men who reported rape perpetration at baseline. We used structural equation modelling (SEM) to examine pathways to rape perpetration. 76.1% of young men had never raped, 10.0% had perpetrated SPR and 13.9% MPR. The factors associated with both MPR and SPR (compared to never having raped) were indicators of socio-economic status (SES), childhood trauma, sexual coercion by a woman, drug and alcohol use, peer pressure susceptibility, having had transactional sex, multiple sexual partners and being physically violent towards a partner. The SEM showed the relationship between SES and rape perpetration to be mediated by gender inequitable masculinity. It was complex as there was a direct path indicating that SES correlated with the masculinity variable directly such that men of higher SES had more gender inequitable masculinities, and indirect path mediated by peer pressure resistance indicated that the former pertained so long as men lacked peer pressure resistance. Having a higher SES conveyed greater resistance for some men. There was also a path mediated through childhood trauma, such that men of lower SES were more likely to have a higher childhood trauma exposure and this correlated with a higher likelihood of having the gender inequitable masculinity (with or without the mediating effect of peer pressure resistance). Both higher and lower socio-economic status were associated with raping. Prevention of rape perpetration must

  17. Accurate metacognition for visual sensory memory representations

    NARCIS (Netherlands)

    Vandenbroucke, A.R.E.; Sligte, I.G.; Barrett, A.B.; Seth, A.K.; Fahrenfort, J.J.; Lamme, V.A.F.

    2014-01-01

    The capacity to attend to multiple objects in the visual field is limited. However, introspectively, people feel that they see the whole visual world at once. Some scholars suggest that this introspective feeling is based on short-lived sensory memory representations, whereas others argue that the

  18. Coordinating different representations in the hippocampus

    Czech Academy of Sciences Publication Activity Database

    Kelemen, Eduard; Fenton, A.A.

    2016-01-01

    Roč. 129, Mar 2016 (2016), s. 50-59 ISSN 1074-7427 R&D Projects: GA ČR(CZ) GA14-03627S Institutional support: RVO:67985823 Keywords : dynamic functional grouping * multiple representations * cognitive control * hippocampus * overdispersion Subject RIV: FH - Neurology Impact factor: 3.543, year: 2016

  19. Social representations: a theoretical approach in health

    Directory of Open Access Journals (Sweden)

    Isaiane Santos Bittencourt

    2011-03-01

    Full Text Available Objective: To present the theory of social representations, placing its epistemology and knowing the basic concepts of its approach as a structural unit of knowledge for health studies. Justification: The use of this theory comes from the need to understand social eventsunder the lens of the meanings constructed by the community. Data Synthesis: This was a descriptive study of literature review, which used as a source of data collection the classical authors of social representations supported by articles from electronic search at Virtual Health Library (VHL. The definition and discussion of collected data enabled to introduce two themes, versed on the history and epistemology of representations and on the structuralapproach of representations in health studies. Conclusion: This review allowed highlight the importance of locating the objects of study with regard to contextual issues of individual and collective histories, valuing the plurality of relations, to come closer to reality that is represented by the subjects.

  20. Prospective Mathematics Teachers' Sense Making of Polynomial Multiplication and Factorization Modeled with Algebra Tiles

    Science.gov (United States)

    Caglayan, Günhan

    2013-01-01

    This study is about prospective secondary mathematics teachers' understanding and sense making of representational quantities generated by algebra tiles, the quantitative units (linear vs. areal) inherent in the nature of these quantities, and the quantitative addition and multiplication operations--referent preserving versus referent…

  1. Do Knowledge-Component Models Need to Incorporate Representational Competencies?

    Science.gov (United States)

    Rau, Martina Angela

    2017-01-01

    Traditional knowledge-component models describe students' content knowledge (e.g., their ability to carry out problem-solving procedures or their ability to reason about a concept). In many STEM domains, instruction uses multiple visual representations such as graphs, figures, and diagrams. The use of visual representations implies a…

  2. Orienting Attention to Sound Object Representations Attenuates Change Deafness

    Science.gov (United States)

    Backer, Kristina C.; Alain, Claude

    2012-01-01

    According to the object-based account of attention, multiple objects coexist in short-term memory (STM), and we can selectively attend to a particular object of interest. Although there is evidence that attention can be directed to visual object representations, the assumption that attention can be oriented to sound object representations has yet…

  3. Multimedia ontology representation and applications

    CERN Document Server

    Chaudhury, Santanu; Ghosh, Hiranmay

    2015-01-01

    The result of more than 15 years of collective research, Multimedia Ontology: Representation and Applications provides a theoretical foundation for understanding the nature of media data and the principles involved in its interpretation. The book presents a unified approach to recent advances in multimedia and explains how a multimedia ontology can fill the semantic gap between concepts and the media world. It relays real-life examples of implementations in different domains to illustrate how this gap can be filled.The book contains information that helps with building semantic, content-based

  4. Representations and Relations

    Czech Academy of Sciences Publication Activity Database

    Koťátko, Petr

    2014-01-01

    Roč. 21, č. 3 (2014), s. 282-302 ISSN 1335-0668 Institutional support: RVO:67985955 Keywords : representation * proposition * truth-conditions * belief-ascriptions * reference * externalism * fiction Subject RIV: AA - Philosophy ; Religion

  5. Boundary representation modelling techniques

    CERN Document Server

    2006-01-01

    Provides the most complete presentation of boundary representation solid modelling yet publishedOffers basic reference information for software developers, application developers and users Includes a historical perspective as well as giving a background for modern research.

  6. Wigner's Symmetry Representation Theorem

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 19; Issue 10. Wigner's Symmetry Representation Theorem: At the Heart of Quantum Field Theory! Aritra Kr Mukhopadhyay. General Article Volume 19 Issue 10 October 2014 pp 900-916 ...

  7. Distributed Representation of Subgraphs

    OpenAIRE

    Adhikari, Bijaya; Zhang, Yao; Ramakrishnan, Naren; Prakash, B. Aditya

    2017-01-01

    Network embeddings have become very popular in learning effective feature representations of networks. Motivated by the recent successes of embeddings in natural language processing, researchers have tried to find network embeddings in order to exploit machine learning algorithms for mining tasks like node classification and edge prediction. However, most of the work focuses on finding distributed representations of nodes, which are inherently ill-suited to tasks such as community detection w...

  8. The endoscopic classification of representations orthogonal and symplectic groups

    CERN Document Server

    Arthur, James

    2013-01-01

    Within the Langlands program, endoscopy is a fundamental process for relating automorphic representations of one group with those of another. In this book, Arthur establishes an endoscopic classification of automorphic representations of orthogonal and symplectic groups G. The representations are shown to occur in families (known as global L-packets and A-packets), which are parametrized by certain self-dual automorphic representations of an associated general linear group GL(N). The central result is a simple and explicit formula for the multiplicity in the automorphic discrete spectrum of G

  9. Hand posture recognition via joint feature sparse representation

    Science.gov (United States)

    Cao, Chuqing; Sun, Ying; Li, Ruifeng; Chen, Lin

    2011-12-01

    In this study, we cast hand posture recognition as a sparse representation problem, and propose a novel approach called joint feature sparse representation classifier for efficient and accurate sparse representation based on multiple features. By integrating different features for sparse representation, including gray-level, texture, and shape feature, the proposed method can fuse benefits of each feature and hence is robust to partial occlusion and varying illumination. Additionally, a new database optimization method is introduced to improve computational speed. Experimental results, based on public and self-build databases, show that our method performs well compared to the state-of-the-art methods for hand posture recognition.

  10. 3D hierarchical spatial representation and memory of multimodal sensory data

    Science.gov (United States)

    Khosla, Deepak; Dow, Paul A.; Huber, David J.

    2009-04-01

    This paper describes an efficient method and system for representing, processing and understanding multi-modal sensory data. More specifically, it describes a computational method and system for how to process and remember multiple locations in multimodal sensory space (e.g., visual, auditory, somatosensory, etc.). The multimodal representation and memory is based on a biologically-inspired hierarchy of spatial representations implemented with novel analogues of real representations used in the human brain. The novelty of the work is in the computationally efficient and robust spatial representation of 3D locations in multimodal sensory space as well as an associated working memory for storage and recall of these representations at the desired level for goal-oriented action. We describe (1) A simple and efficient method for human-like hierarchical spatial representations of sensory data and how to associate, integrate and convert between these representations (head-centered coordinate system, body-centered coordinate, etc.); (2) a robust method for training and learning a mapping of points in multimodal sensory space (e.g., camera-visible object positions, location of auditory sources, etc.) to the above hierarchical spatial representations; and (3) a specification and implementation of a hierarchical spatial working memory based on the above for storage and recall at the desired level for goal-oriented action(s). This work is most useful for any machine or human-machine application that requires processing of multimodal sensory inputs, making sense of it from a spatial perspective (e.g., where is the sensory information coming from with respect to the machine and its parts) and then taking some goal-oriented action based on this spatial understanding. A multi-level spatial representation hierarchy means that heterogeneous sensory inputs (e.g., visual, auditory, somatosensory, etc.) can map onto the hierarchy at different levels. When controlling various machine

  11. Distorted representation in visual tourism research

    DEFF Research Database (Denmark)

    Jensen, Martin Trandberg

    2016-01-01

    Tourism research has recently been informed by non-representational theories to highlight the socio-material, embodied and heterogeneous composition of tourist experiences. These advances have contributed to further reflexivity and called for novel ways to animate representations. On this backgro......Tourism research has recently been informed by non-representational theories to highlight the socio-material, embodied and heterogeneous composition of tourist experiences. These advances have contributed to further reflexivity and called for novel ways to animate representations....... On this background, this paper develops the notion ‘distorted representation’ to illustrate that blurred and obscure photos can in fact be intelligible and sensible in understanding tourism. Through an exploration of the overwhelmed and unintended practices of visual fieldwork, distorted representation illustrates...... how photographic materialities, performativities and sensations contribute to new tourism knowledges. While highlighting the potential of distorted representation, the paper posits a cautionary note in regards to the influential role of academic journals in determining the qualities of visual data...

  12. Mental representation and motor imagery training.

    Science.gov (United States)

    Schack, Thomas; Essig, Kai; Frank, Cornelia; Koester, Dirk

    2014-01-01

    Research in sports, dance and rehabilitation has shown that basic action concepts (BACs) are fundamental building blocks of mental action representations. BACs are based on chunked body postures related to common functions for realizing action goals. In this paper, we outline issues in research methodology and an experimental method, the structural dimensional analysis of mental representation (SDA-M), to assess action-relevant representational structures that reflect the organization of BACs. The SDA-M reveals a strong relationship between cognitive representation and performance if complex actions are performed. We show how the SDA-M can improve motor imagery training and how it contributes to our understanding of coaching processes. The SDA-M capitalizes on the objective measurement of individual mental movement representations before training and the integration of these results into the motor imagery training. Such motor imagery training based on mental representations (MTMR) has been applied successfully in professional sports such as golf, volleyball, gymnastics, windsurfing, and recently in the rehabilitation of patients who have suffered a stroke.

  13. Mental Representation and Motor Imagery Training

    Directory of Open Access Journals (Sweden)

    Thomas eSchack

    2014-05-01

    Full Text Available Research in sports, dance and rehabilitation has shown that Basic Action Concepts (BACs are fundamental building blocks of mental action representations. BACs are based on chunked body postures related to common functions for realizing action goals. In this paper, we outline issues in research methodology and an experimental method, SDA-M (structural dimensional analysis of mental representation, to assess action-relevant representational structures that reflect the organization of BACs. The SDA-M reveals a strong relationship between cognitive representation and performance if complex actions are performed. We show how the SDA-M can improve motor imagery training and how it contributes to our understanding of coaching processes. The SDA-M capitalizes on the objective measurement of individual mental movement representations before training and the integration of these results into the motor imagery training. Such motor imagery training based on mental representations has been applied successfully in professional sports such as golf, volleyball, gymnastics, windsurfing, and recently in the rehabilitation of patients who have suffered a stroke.

  14. Pursuing the method of multiple working hypotheses for hydrological modeling

    Science.gov (United States)

    Clark, M. P.; Kavetski, D.; Fenicia, F.

    2012-12-01

    Ambiguities in the representation of environmental processes have manifested themselves in a plethora of hydrological models, differing in almost every aspect of their conceptualization and implementation. The current overabundance of models is symptomatic of an insufficient scientific understanding of environmental dynamics at the catchment scale, which can be attributed to difficulties in measuring and representing the heterogeneity encountered in natural systems. This presentation advocates using the method of multiple working hypotheses for systematic and stringent testing of model alternatives in hydrology. We discuss how the multiple hypothesis approach provides the flexibility to formulate alternative representations (hypotheses) describing both individual processes and the overall system. When combined with incisive diagnostics to scrutinize multiple model representations against observed data, this provides hydrologists with a powerful and systematic approach for model development and improvement. Multiple hypothesis frameworks also support a broader coverage of the model hypothesis space and hence improve the quantification of predictive uncertainty arising from system and component non-identifiabilities. As part of discussing the advantages and limitations of multiple hypothesis frameworks, we critically review major contemporary challenges in hydrological hypothesis-testing, including exploiting different types of data to investigate the fidelity of alternative process representations, accounting for model structure ambiguities arising from major uncertainties in environmental data, quantifying regional differences in dominant hydrological processes, and the grander challenge of understanding the self-organization and optimality principles that may functionally explain and describe the heterogeneities evident in most environmental systems. We assess recent progress in these research directions, and how new advances are possible using multiple hypothesis

  15. Questions of Representations in Architecture

    DEFF Research Database (Denmark)

    2015-01-01

    Questions of Representations in Architecture is the first major Danish contribution to the current international discussion on architects' use of representations and the significance of visual media for architecture.......Questions of Representations in Architecture is the first major Danish contribution to the current international discussion on architects' use of representations and the significance of visual media for architecture....

  16. Atypical Neural Self-Representation in Autism

    Science.gov (United States)

    Lombardo, Michael V.; Chakrabarti, Bhismadev; Bullmore, Edward T.; Sadek, Susan A.; Pasco, Greg; Wheelwright, Sally J.; Suckling, John; Baron-Cohen, Simon

    2010-01-01

    The "self" is a complex multidimensional construct deeply embedded and in many ways defined by our relations with the social world. Individuals with autism are impaired in both self-referential and other-referential social cognitive processing. Atypical neural representation of the self may be a key to understanding the nature of such impairments.…

  17. Toward a Theory of Representation Design

    Science.gov (United States)

    1989-05-01

    understanding. This report describes research done at the Artificial Inteligence Laboratory of the Massachusetts Institute of Technology. Support for this...AD-A210 885 Technical Report 1128 Toward a Theory of Representation Design Jeffrey Van Baale MIT Artificial Intelligence Laboratory DTIC ELECTE A... Artificial Intelligence Laboratory 545 Technology Square Cambridge, MA 02139 11. CONTROLLING OFFICE NAME AND ADDRESS 11. REPORT DATE Advanced Research

  18. Electromagnetic Concepts in Mathematical Representation of Physics.

    Science.gov (United States)

    Albe, Virginie; Venturini, Patrice; Lascours, Jean

    2001-01-01

    Addresses the use of mathematics when studying the physics of electromagnetism. Focuses on common electromagnetic concepts and their associated mathematical representation and arithmetical tools. Concludes that most students do not understand the significant aspects of physical situations and have difficulty using relationships and models specific…

  19. Non-uniform tube representation of proteins

    DEFF Research Database (Denmark)

    Hansen, Mikael Sonne

    might not correctly capture volume exclusion - of crucial importance when trying to understand a proteins $3$d-structure. We propose a new reduced model treating the protein as a non-uniform tube with a radius reflecting the positions of atoms. The tube representation is well suited considering X...

  20. Operator representations of frames

    DEFF Research Database (Denmark)

    Christensen, Ole; Hasannasab, Marzieh

    2017-01-01

    The purpose of this paper is to consider representations of frames {fk}k∈I in a Hilbert space ℋ of the form {fk}k∈I = {Tkf0}k∈I for a linear operator T; here the index set I is either ℤ or ℒ0. While a representation of this form is available under weak conditions on the frame, the analysis...... of the properties of the operator T requires more work. For example it is a delicate issue to obtain a representation with a bounded operator, and the availability of such a representation not only depends on the frame considered as a set, but also on the chosen indexing. Using results from operator theory we show...... that by embedding the Hilbert space ℋ into a larger Hilbert space, we can always represent a frame via iterations of a bounded operator, composed with the orthogonal projection onto ℋ. The paper closes with a discussion of an open problem concerning representations of Gabor frames via iterations of a bounded...

  1. Representation Elements of Spatial Thinking

    Science.gov (United States)

    Fiantika, F. R.

    2017-04-01

    This paper aims to add a reference in revealing spatial thinking. There several definitions of spatial thinking but it is not easy to defining it. We can start to discuss the concept, its basic a forming representation. Initially, the five sense catch the natural phenomenon and forward it to memory for processing. Abstraction plays a role in processing information into a concept. There are two types of representation, namely internal representation and external representation. The internal representation is also known as mental representation; this representation is in the human mind. The external representation may include images, auditory and kinesthetic which can be used to describe, explain and communicate the structure, operation, the function of the object as well as relationships. There are two main elements, representations properties and object relationships. These elements play a role in forming a representation.

  2. Unpacking Exoplanet Detection Using Pedagogical Discipline Representations (PDRs)

    Science.gov (United States)

    Prather, Edward E.; Chambers, Timothy G.; Wallace, Colin Scott; Brissenden, Gina

    2017-01-01

    Successful educators know the importance of using multiple representations to teach the content of their disciplines. We have all seen the moments of epiphany that can be inspired when engaging with just the right representation of a difficult concept. The formal study of the cognitive impact of different representations on learners is now an active area of education research. The affordances of a particular representation are defined as the elements of disciplinary knowledge that students are able to access and reason about using that representation. Instructors with expert pedagogical content knowledge teach each topic using representations with complementary affordances, maximizing their students’ opportunity to develop fluency with all aspects of the topic. The work presented here examines how we have applied the theory of affordances to the development of pedagogical discipline representation (PDR) in an effort to provide access to, and help non-science-majors engage in expert-like reasoning about, general relativity as applied to detection of exoplanets. We define a pedagogical discipline representation (PDR) as a representation that has been uniquely tailored for the purpose of teaching a specific topic within a discipline. PDRs can be simplified versions of expert representations or can be highly contextualized with features that purposefully help unpack specific reasoning or concepts, and engage learners’ pre-existing mental models while promoting and enabling critical discourse. Examples of PDRs used for instruction and assessment will be provided along with preliminary results documenting the effectiveness of their use in the classroom.

  3. Narcissism and relational representations among psychiatric outpatients.

    Science.gov (United States)

    Kealy, David; Ogrodniczuk, John S; Joyce, Anthony S; Steinberg, Paul I; Piper, William E

    2015-06-01

    Pathological narcissism is associated with maladaptive interpersonal behavior, although less is known regarding the internal relational representations of narcissistic patients. The authors examined the relationship between pathological narcissism and two constructs that reflect internal representations of relational patterns: quality of object relations and attachment style. Patients attending a psychiatric day treatment program (N = 218) completed measures of narcissism, general psychiatric distress, and attachment style in terms of attachment avoidance and anxiety. A semistructured interview was used to assess quality of object relations. Multiple regression analysis was conducted, controlling for general psychiatric distress. Pathological narcissism was associated with anxious attachment, but not with avoidant attachment. Narcissism was also associated with lower levels of quality of object relations. The implications of these results are discussed in terms of internal representations of self-other relations.

  4. Analysis of the Chemical Representations in Secondary Lebanese Chemistry Textbooks

    Science.gov (United States)

    Shehab, Saadeddine Salim; BouJaoude, Saouma

    2017-01-01

    This study focused on the requirements that chemical representations should meet in textbooks in order to enhance conceptual understanding. Specifically, the purpose of this study was to evaluate the chemical representations that are present in 7 secondary Lebanese chemistry textbooks. To achieve the latter purpose, an instrument adapted from…

  5. Promoting Representational Competence with Molecular Models in Organic Chemistry

    Science.gov (United States)

    Stull, Andrew T.; Gainer, Morgan; Padalkar, Shamin; Hegarty, Mary

    2016-01-01

    Mastering the many different diagrammatic representations of molecules used in organic chemistry is challenging for students. This article summarizes recent research showing that manipulating 3-D molecular models can facilitate the understanding and use of these representations. Results indicate that students are more successful in translating…

  6. Representations of HIV/AIDS management in South African ...

    African Journals Online (AJOL)

    Through an analysis of newspaper articles, we explore the dominant representations of HIV/AIDS management circulating in the South African public sphere and examine how community engagement is depicted. We highlight the way media representations reflect narrow understandings of HIV and AIDS as a predominantly ...

  7. Representation Discovery using Harmonic Analysis

    CERN Document Server

    Mahadevan, Sridhar

    2008-01-01

    Representations are at the heart of artificial intelligence (AI). This book is devoted to the problem of representation discovery: how can an intelligent system construct representations from its experience? Representation discovery re-parameterizes the state space - prior to the application of information retrieval, machine learning, or optimization techniques - facilitating later inference processes by constructing new task-specific bases adapted to the state space geometry. This book presents a general approach to representation discovery using the framework of harmonic analysis, in particu

  8. Introduction to computer data representation

    CERN Document Server

    Fenwick, Peter

    2014-01-01

    Introduction to Computer Data Representation introduces readers to the representation of data within computers. Starting from basic principles of number representation in computers, the book covers the representation of both integer and floating point numbers, and characters or text. It comprehensively explains the main techniques of computer arithmetic and logical manipulation. The book also features chapters covering the less usual topics of basic checksums and 'universal' or variable length representations for integers, with additional coverage of Gray Codes, BCD codes and logarithmic repre

  9. Contractions of group representations. - I

    International Nuclear Information System (INIS)

    Celeghini, E.; Tarlini, M.

    1981-01-01

    A new definition of contraction as a limit on the parameters defining the basis of the space of representations is given. From the representations of the original group, those of the contracted one are directly obtained. The contraction of inner automorphisms into outer automorphisms and the splitting of one representation into representations of the same or different group are discussed and illustrated by examples. The procedure is also a technique for the study of representations of non-semi-simple groups. (author)

  10. Teaching Teaching & Understanding Understanding

    DEFF Research Database (Denmark)

    2006-01-01

    "Teaching Teaching & Understanding Understanding" is a 19-minute award-winning short-film about teaching at university and higher-level educational institutions. It is based on the "Constructive Alignment" theory developed by Prof. John Biggs. The film delivers a foundation for understanding what...

  11. Post-representational cartography

    Directory of Open Access Journals (Sweden)

    Rob Kitchin

    2010-03-01

    Full Text Available Over the past decade there has been a move amongst critical cartographers to rethink maps from a post-representational perspective – that is, a vantage point that does not privilege representational modes of thinking (wherein maps are assumed to be mirrors of the world and automatically presumes the ontological security of a map as a map, but rather rethinks and destabilises such notions. This new theorisation extends beyond the earlier critiques of Brian Harley (1989 that argued maps were social constructions. For Harley a map still conveyed the truth of a landscape, albeit its message was bound within the ideological frame of its creator. He thus advocated a strategy of identifying the politics of representation within maps in order to circumnavigate them (to reveal the truth lurking underneath, with the ontology of cartographic practice remaining unquestioned.

  12. Representations of distance

    DEFF Research Database (Denmark)

    Larsen, Gunvor Riber

    2017-01-01

    This paper explores how Danish tourists represent distance in relation to their holiday mobility and how these representations of distance are a result of being aero-mobile as opposed to being land-mobile. Based on interviews with Danish tourists, whose holiday mobility ranges from the European...... continent to global destinations, the first part of this qualitative study identifies three categories of representations of distance that show how distance is being ‘translated’ by the tourists into non-geometric forms: distance as resources, distance as accessibility, and distance as knowledge....... The representations of distance articulated by the Danish tourists show that distance is often not viewed in ‘just’ kilometres. Rather, it is understood in forms that express how transcending the physical distance through holiday mobility is dependent on individual social and economic contexts, and on whether...

  13. Additive and polynomial representations

    CERN Document Server

    Krantz, David H; Suppes, Patrick

    1971-01-01

    Additive and Polynomial Representations deals with major representation theorems in which the qualitative structure is reflected as some polynomial function of one or more numerical functions defined on the basic entities. Examples are additive expressions of a single measure (such as the probability of disjoint events being the sum of their probabilities), and additive expressions of two measures (such as the logarithm of momentum being the sum of log mass and log velocity terms). The book describes the three basic procedures of fundamental measurement as the mathematical pivot, as the utiliz

  14. On the spinor representation

    Energy Technology Data Exchange (ETDEWEB)

    Hoff da Silva, J.M.; Rogerio, R.J.B. [Universidade Estadual Paulista, Departamento de Fisica e Quimica, Guaratingueta, SP (Brazil); Villalobos, C.H.C. [Universidade Estadual Paulista, Departamento de Fisica e Quimica, Guaratingueta, SP (Brazil); Universidade Federal Fluminense, Instituto de Fisica, Niteroi, RJ (Brazil); Rocha, Roldao da [Universidade Federal do ABC-UFABC, Centro de Matematica, Computacao e Cognicao, Santo Andre (Brazil)

    2017-07-15

    A systematic study of the spinor representation by means of the fermionic physical space is accomplished and implemented. The spinor representation space is shown to be constrained by the Fierz-Pauli-Kofink identities among the spinor bilinear covariants. A robust geometric and topological structure can be manifested from the spinor space, wherein the first and second homotopy groups play prominent roles on the underlying physical properties, associated to fermionic fields. The mapping that changes spinor fields classes is then exemplified, in an Einstein-Dirac system that provides the spacetime generated by a fermion. (orig.)

  15. Mobilities and Representations

    DEFF Research Database (Denmark)

    Thelle, Mikkel

    2017-01-01

    , literature, and film. Moreover, we hope the authors of future reviews will reflect on the ways they approached those representations. Such commentaries would provide valuable methodological insights, and we hope to begin that effort with this interview. We have asked four prominent mobility scholars......As the centerpiece of the eighth T2M yearbook, the following interview about representations of mobility signals a new and exciting focus area for Mobility in History. In future issues we hope to include reviews that grapple more with how mobilities have been imagined and represented in the arts...

  16. Understanding balance differences in individuals with multiple sclerosis with mild disability: An investigation of differences in sensory feedback on postural and dynamic balance control

    Science.gov (United States)

    Denomme, Luke T.

    Multiple sclerosis (MS) is an autoimmune disease that affects the central nervous system (CNS) and causes a broad range of neurological symptoms. One of the most common symptoms experienced by individuals with MS is poor balance control during standing and walking. The main mechanism underlying impaired balance control in MS appears to result from slowed somatosensory conduction and impaired central integration. The current thesis assessed postural and dynamic control of balance of 'individuals with MS with mild disability' (IwMS). IwMS were compared to 'healthy age-matched individuals' (HAMI) and community-dwelling 'older adults' (OA). The purpose of this thesis was to quantify differences in postural and dynamic control of balance in IwMS to the two populations who display balance control differences across the lifespan and represent two extreme ends of the balance control continuum due to natural aging. IwMS (n = 12, x¯age: 44 +/- 9.4 years), HAMI (n = 12, x¯age: 45 +/- 9.9 years) and community-dwelling OA (n = 12, x¯ age: 68.1 +/- 4.5 years) postural and dynamic balance control were evaluated during a Romberg task as well as a dynamic steering task. The Romberg task required participants to stand with their feet together and hands by their sides for 45 seconds with either their eyes open or closed. The dynamic steering task required participants to walk and change direction along the M-L plane towards a visual goal. Results from these two tasks reveal that IwMS display differences in postural control when compared to HAMI when vision was removed as well as differences in dynamic stability margin during steering situations. During the postural control task IwMS displayed faster A-P and M-L COP velocities when vision was removed and their COP position was closer to their self-selected maximum stability limits compared to HAMI. Assessment of dynamic stability during the steering task revealed that IwMS displayed reduced walking speed and cadence during the

  17. O potencial das representações sociais para a compreensão interdisciplinar da realidade: Geografia e Psicologia Ambiental The potential of the social representations aimed at the understanding of interdisciplinar reality: Geography and Environmental Psychology

    Directory of Open Access Journals (Sweden)

    Marília L. Peluso

    2003-08-01

    Full Text Available O artigo pretende ser uma contribuição para as discussões sobre a interdisciplinaridade em Psicologia Ambiental e Geografia. Espera-se contribuir para o debate dentro do pressuposto de que a afinidade entre as duas áreas se tece quando se entende o espaço e o ambiente como atores sociais, isto é, eles não são neutros, mas atuam sobre as sociedades e os sujeitos que os produziram, construíram e organizaram. Vai-se trabalhar com os pressupostos de que as fronteiras entre as ciências são tênues e que, para ultrapassá-las, deve-se romper com a compartimentação e articular pensamento e práticas sobre a realidade de maneira interdisciplinar. Considera-se que as representações sociais permitem ultrapassar as fronteiras entre as duas ciências e desvendar complexas relações psíquicas e sociais, tendo como objeto empírico as periferias do Distrito Federal.The article intends to be a contribution for the discussions involving the interdisciplinarity between Geography and Environmental Psychology. This paper is expected to contribute to that debate based on the affinity between the two areas when space and environment are understood as social actors, that is, they are not neutral, but act upon societies and individuals who had produced, constructed and organized them. The limits among sciences are seen as tenuous and should be exceeded in order to surpass such partitioning of reality by means of interdisciplinary articulation of ideas and practices. It is considered that the social representations allow to overrun the limits between the two sciences and to unmask complex psychic and social relations within the surrounding areas of the Federal District.

  18. Using normalisation process theory to understand barriers and facilitators to implementing mindfulness-based stress reduction for people with multiple sclerosis.

    Science.gov (United States)

    Simpson, Robert; Simpson, Sharon; Wood, Karen; Mercer, Stewart W; Mair, Frances S

    2018-01-01

    Objectives To study barriers and facilitators to implementation of mindfulness-based stress reduction for people with multiple sclerosis. Methods Qualitative interviews were used to explore barriers and facilitators to implementation of mindfulness-based stress reduction, including 33 people with multiple sclerosis, 6 multiple sclerosis clinicians and 2 course instructors. Normalisation process theory provided the underpinning conceptual framework. Data were analysed deductively using normalisation process theory constructs (coherence, cognitive participation, collective action and reflexive monitoring). Results Key barriers included mismatched stakeholder expectations, lack of knowledge about mindfulness-based stress reduction, high levels of comorbidity and disability and skepticism about embedding mindfulness-based stress reduction in routine multiple sclerosis care. Facilitators to implementation included introducing a pre-course orientation session; adaptations to mindfulness-based stress reduction to accommodate comorbidity and disability and participants suggested smaller, shorter classes, shortened practices, exclusion of mindful-walking and more time with peers. Post-mindfulness-based stress reduction booster sessions may be required, and objective and subjective reports of benefit would increase clinician confidence in mindfulness-based stress reduction. Discussion Multiple sclerosis patients and clinicians know little about mindfulness-based stress reduction. Mismatched expectations are a barrier to participation, as is rigid application of mindfulness-based stress reduction in the context of disability. Course adaptations in response to patient needs would facilitate uptake and utilisation. Rendering access to mindfulness-based stress reduction rapid and flexible could facilitate implementation. Embedded outcome assessment is desirable.

  19. Minimal Surfaces for Hitchin Representations

    DEFF Research Database (Denmark)

    Li, Qiongling; Dai, Song

    2018-01-01

    . In this paper, we investigate the properties of immersed minimal surfaces inside symmetric space associated to a subloci of Hitchin component: $q_n$ and $q_{n-1}$ case. First, we show that the pullback metric of the minimal surface dominates a constant multiple of the hyperbolic metric in the same conformal...... class and has a strong rigidity property. Secondly, we show that the immersed minimal surface is never tangential to any flat inside the symmetric space. As a direct corollary, the pullback metric of the minimal surface is always strictly negatively curved. In the end, we find a fully decoupled system......Given a reductive representation $\\rho: \\pi_1(S)\\rightarrow G$, there exists a $\\rho$-equivariant harmonic map $f$ from the universal cover of a fixed Riemann surface $\\Sigma$ to the symmetric space $G/K$ associated to $G$. If the Hopf differential of $f$ vanishes, the harmonic map is then minimal...

  20. Assessment of representational competence in kinematics

    Science.gov (United States)

    Klein, P.; Müller, A.; Kuhn, J.

    2017-06-01

    A two-tier instrument for representational competence in the field of kinematics (KiRC) is presented, designed for a standard (1st year) calculus-based introductory mechanics course. It comprises 11 multiple choice (MC) and 7 multiple true-false (MTF) questions involving multiple representational formats, such as graphs, pictures, and formal (mathematical) expressions (1st tier). Furthermore, students express their answer confidence for selected items, providing additional information (2nd tier). Measurement characteristics of KiRC were assessed in a validation sample (pre- and post-test, N =83 and N =46 , respectively), including usefulness for measuring learning gain. Validity is checked by interviews and by benchmarking KiRC against related measures. Values for item difficulty, discrimination, and consistency are in the desired ranges; in particular, a good reliability was obtained (KR 20 =0.86 ). Confidence intervals were computed and a replication study yielded values within the latter. For practical and research purposes, KiRC as a diagnostic tool goes beyond related extant instruments both for the representational formats (e.g., mathematical expressions) and for the scope of content covered (e.g., choice of coordinate systems). Together with the satisfactory psychometric properties it appears a versatile and reliable tool for assessing students' representational competency in kinematics (and of its potential change). Confidence judgments add further information to the diagnostic potential of the test, in particular for representational misconceptions. Moreover, we present an analytic result for the question—arising from guessing correction or educational considerations—of how the total effect size (Cohen's d ) varies upon combination of two test components with known individual effect sizes, and then discuss the results in the case of KiRC (MC and MTF combination). The introduced method of test combination analysis can be applied to any test comprising

  1. Ready, set, go: a cross-sectional survey to understand priorities and preferences for multiple health behaviour change in a highly disadvantaged group.

    Science.gov (United States)

    Noble, Natasha; Paul, Christine; Sanson-Fisher, Robert; Turon, Heidi; Turner, Nicole; Conigrave, Katherine

    2016-09-13

    Socially disadvantaged groups, such as Aboriginal Australians, tend to have a high prevalence of multiple lifestyle risk factors, increasing the risk of disease and underscoring the need for services to address multiple health behaviours. The aims of this study were to explore, among a socially disadvantaged group of people attending an Aboriginal Community Controlled Health Service (ACCHS): a) readiness to change health behaviours; b) acceptability of addressing multiple risk factors sequentially or simultaneously; and c) preferred types of support services. People attending an ACCHS in regional New South Wales (NSW) completed a touchscreen survey while waiting for their appointment. The survey assessed participant health risk status, which health risks they would like to change, whether they preferred multiple health changes to be made together or separately, and the types of support they would use. Of the 211 participants who completed the survey, 94 % reported multiple (two or more) health risks. There was a high willingness to change, with 69 % of current smokers wanting to cut down or quit, 51 % of overweight or obese participants wanting to lose weight and 44 % of those using drugs in the last 12 months wanting to stop or cut down. Of participants who wanted to make more than one health change, over half would be willing to make simultaneous or over-lapping health changes. The most popular types of support were help from a doctor or Health Worker and seeing a specialist, with less than a quarter of participants preferring telephone or electronic (internet or smart phone) forms of assistance. The importance of involving family members was also identified. Strategies addressing multiple health behaviour changes are likely to be acceptable for people attending an ACCHS, but may need to allow flexibility in the choice of initial target behaviour, timing of changes, and the format of support provided.

  2. Linking somatic and symbolic representation in semantic memory: the dynamic multilevel reactivation framework.

    Science.gov (United States)

    Reilly, Jamie; Peelle, Jonathan E; Garcia, Amanda; Crutch, Sebastian J

    2016-08-01

    Biological plausibility is an essential constraint for any viable model of semantic memory. Yet, we have only the most rudimentary understanding of how the human brain conducts abstract symbolic transformations that underlie word and object meaning. Neuroscience has evolved a sophisticated arsenal of techniques for elucidating the architecture of conceptual representation. Nevertheless, theoretical convergence remains elusive. Here we describe several contrastive approaches to the organization of semantic knowledge, and in turn we offer our own perspective on two recurring questions in semantic memory research: (1) to what extent are conceptual representations mediated by sensorimotor knowledge (i.e., to what degree is semantic memory embodied)? (2) How might an embodied semantic system represent abstract concepts such as modularity, symbol, or proposition? To address these questions, we review the merits of sensorimotor (i.e., embodied) and amodal (i.e., disembodied) semantic theories and address the neurobiological constraints underlying each. We conclude that the shortcomings of both perspectives in their extreme forms necessitate a hybrid middle ground. We accordingly propose the Dynamic Multilevel Reactivation Framework-an integrative model predicated upon flexible interplay between sensorimotor and amodal symbolic representations mediated by multiple cortical hubs. We discuss applications of the dynamic multilevel reactivation framework to abstract and concrete concept representation and describe how a multidimensional conceptual topography based on emotion, sensation, and magnitude can successfully frame a semantic space containing meanings for both abstract and concrete words. The consideration of 'abstract conceptual features' does not diminish the role of logical and/or executive processing in activating, manipulating and using information stored in conceptual representations. Rather, it proposes that the materials upon which these processes operate

  3. Between Representation and Eternity

    DEFF Research Database (Denmark)

    Atzbach, Rainer

    2016-01-01

    . At death, an indi- vidual’s corpse and burial primarily reflect the social act of representation during the funeral. The position of the arms, which have incorrectly been used as a chronological tool in Scandinavia, may indicate an evolution from a more collective act of prayer up to the eleventh century...

  4. Reflective Abstraction and Representation.

    Science.gov (United States)

    Lewin, Philip

    Piaget's theory of reflective abstraction can supplement cognitive science models of representation by specifying both the act of construction and the component steps through which knowers pass as they acquire knowledge. But, while approaches suggested by cognitive science supplement Piaget by awakening researchers to the role of auxiliary factors…

  5. Hyperfinite representation of distributions

    Indian Academy of Sciences (India)

    A nonstandard treatment of the theory of distributions in terms of a hyperfinite representa- tion has been presented in papers [2,3] by Kinoshita. A further exploitation of this treatment in an N-dimensional context has been given by Grenier [1]. In the present paper we offer a different approach to the hyperfinite representation, ...

  6. Going beyond representational anthropology

    DEFF Research Database (Denmark)

    Winther, Ida Wentzel

    Going beyond representational anthropology: Re-presenting bodily, emotional and virtual practices in everyday life. Separated youngsters and families in Greenland Greenland is a huge island, with a total of four high-schools. Many youngsters (age 16-18) move far away from home in order to get...

  7. Representation of the Divine

    DEFF Research Database (Denmark)

    Loddegaard, Anne

    2009-01-01

    out of place in a novel belonging to the serious combat literature of the Catholic Revival, and the direct representation of the supernatural is also surprising because previous Catholic Revival novelists, such as Léon Bloy and Karl-Joris Huysmans, maintain a realistic, non-magical world and deal...

  8. Representation of the Divine

    DEFF Research Database (Denmark)

    Loddegaard, Anne

    2012-01-01

    out of place in a novel belonging to the serious combat literature of the Catholic Revival, and the direct representation of the supernatural is also surprising because previous Catholic Revival novelists, such as Léon Bloy and Karl-Joris Huysmans, maintain a realistic, non-magical world and deal...

  9. Moment graphs and representations

    DEFF Research Database (Denmark)

    Jantzen, Jens Carsten

    2012-01-01

    Moment graphs and sheaves on moment graphs are basically combinatorial objects that have be used to describe equivariant intersectiion cohomology. In these lectures we are going to show that they can be used to provide a direct link from this cohomology to the representation theory of simple Lie...

  10. How Do Students Learn to See Concepts in Visualizations? Social Learning Mechanisms with Physical and Virtual Representations

    Science.gov (United States)

    Rau, Martina A.

    2017-01-01

    STEM instruction often uses visual representations. To benefit from these, students need to understand how representations show domain-relevant concepts. Yet, this is difficult for students. Prior research shows that physical representations (objects that students manipulate by hand) and virtual representations (objects on a computer screen that…

  11. Specialized mechanisms for theory of mind: are mental representations special because they are mental or because they are representations?

    Science.gov (United States)

    Cohen, Adam S; Sasaki, Joni Y; German, Tamsin C

    2015-03-01

    Does theory of mind depend on a capacity to reason about representations generally or on mechanisms selective for the processing of mental state representations? In four experiments, participants reasoned about beliefs (mental representations) and notes (non-mental, linguistic representations), which according to two prominent theories are closely matched representations because both are represented propositionally. Reaction times were faster and accuracies higher when participants endorsed or rejected statements about false beliefs than about false notes (Experiment 1), even when statements emphasized representational format (Experiment 2), which should have favored the activation of representation concepts. Experiments 3 and 4 ruled out a counterhypothesis that differences in task demands were responsible for the advantage in belief processing. These results demonstrate for the first time that understanding of mental and linguistic representations can be dissociated even though both may carry propositional content, supporting the theory that mechanisms governing theory of mind reasoning are narrowly specialized to process mental states, not representations more broadly. Extending this theory, we discuss whether less efficient processing of non-mental representations may be a by-product of mechanisms specialized for processing mental states. Crown Copyright © 2014. Published by Elsevier B.V. All rights reserved.

  12. Action simulation: time course and representational mechanisms

    Science.gov (United States)

    Springer, Anne; Parkinson, Jim; Prinz, Wolfgang

    2013-01-01

    The notion of action simulation refers to the ability to re-enact foreign actions (i.e., actions observed in other individuals). Simulating others' actions implies a mirroring of their activities, based on one's own sensorimotor competencies. Here, we discuss theoretical and experimental approaches to action simulation and the study of its representational underpinnings. One focus of our discussion is on the timing of internal simulation and its relation to the timing of external action, and a paradigm that requires participants to predict the future course of actions that are temporarily occluded from view. We address transitions between perceptual mechanisms (referring to action representation before and after occlusion) and simulation mechanisms (referring to action representation during occlusion). Findings suggest that action simulation runs in real-time; acting on newly created action representations rather than relying on continuous visual extrapolations. A further focus of our discussion pertains to the functional characteristics of the mechanisms involved in predicting other people's actions. We propose that two processes are engaged, dynamic updating and static matching, which may draw on both semantic and motor information. In a concluding section, we discuss these findings in the context of broader theoretical issues related to action and event representation, arguing that a detailed functional analysis of action simulation in cognitive, neural, and computational terms may help to further advance our understanding of action cognition and motor control. PMID:23847563

  13. Librarians on animes: fictional representations and reality

    Directory of Open Access Journals (Sweden)

    Valdir Jose Morigi

    2017-10-01

    Full Text Available Introduction: This work investigates representations about librarians on four animes (japanese animations. It contextualizes the concepts of culture, social representations and representations about librarians. It conceptualizes the animes and emphasize their importance in japanese culture. Objective: To understand how representations about librarians on animes are manifested. Methodology: It utilizes qualitative methodology, being basic, descriptive and has a documental procedure. It uses narratology as a method, identifying the theme, the plot, the environment and the time of the stories, in addition to the physical, psychological and social characteristics of the librarian characters. Results: It discourses about the anchorages observed in the librarian characters on the analyzed animes, making brief comparations between the Eastern and the Western visions about the librarian. In opposite to some stereotypes about the profession, some librarian characters are identified as fighting to pass the information to the user, being even engaged and active on politics. Conclusions: It concludes that the representations about librarians are anchored specially on the vision of the librarian as a guardian, as much of the books, as of the library and memory.

  14. Supply chain management: a framework of understanding

    Directory of Open Access Journals (Sweden)

    Du Toit, Deirdre

    2014-11-01

    Full Text Available The topic of supply chain management (SCM is complex to understand because it encompasses many different flows of activities, components, functions, and role-players. The literature is scattered across multiple functions, varies in scope, and is often confined to certain elements within SCM. This article aims to provide a literature overview of SCM. It is explained with the aid of a newly-developed framework of understanding that offers a graphical representation of the term. It unifies and condenses different components within SCM and shows the relationship between them. The framework was developed by identifying the main themes in the definitions for SCM, examining existing categorisations and frameworks in SCM, and analysing frameworks in other disciplines. The outcome of this article can be used as a guide to explain and orientate researchers and practitioners in the field.

  15. Triple representation of language, working memory, social and emotion processing in the cerebellum: convergent evidence from task and seed-based resting-state fMRI analyses in a single large cohort.

    Science.gov (United States)

    Guell, Xavier; Gabrieli, John D E; Schmahmann, Jeremy D

    2018-02-02

    Delineation of functional topography is critical to the evolving understanding of the cerebellum's role in a wide range of nervous system functions. We used data from the Human Connectome Project (n = 787) to analyze cerebellar fMRI task activation (motor, working memory, language, social and emotion processing) and resting-state functional connectivity calculated from cerebral cortical seeds corresponding to the peak Cohen's d of each task contrast. The combination of exceptional statistical power, activation from both motor and multiple non-motor tasks in the same participants, and convergent resting-state networks in the same participants revealed novel aspects of the functional topography of the human cerebellum. Consistent with prior studies there were two distinct representations of motor activation. Newly revealed were three distinct representations each for working memory, language, social, and emotional task processing that were largely separate for these four cognitive and affective domains. In most cases, the task-based activations and the corresponding resting-network correlations were congruent in identifying the two motor representations and the three non-motor representations that were unique to working memory, language, social cognition, and emotion. The definitive localization and characterization of distinct triple representations for cognition and emotion task processing in the cerebellum opens up new basic science questions as to why there are triple representations (what different functions are enabled by the different representations?) and new clinical questions (what are the differing consequences of lesions to the different representations?). Copyright © 2018 Elsevier Inc. All rights reserved.

  16. Representations of affine Hecke algebras

    CERN Document Server

    Xi, Nanhua

    1994-01-01

    Kazhdan and Lusztig classified the simple modules of an affine Hecke algebra Hq (q E C*) provided that q is not a root of 1 (Invent. Math. 1987). Ginzburg had some very interesting work on affine Hecke algebras. Combining these results simple Hq-modules can be classified provided that the order of q is not too small. These Lecture Notes of N. Xi show that the classification of simple Hq-modules is essentially different from general cases when q is a root of 1 of certain orders. In addition the based rings of affine Weyl groups are shown to be of interest in understanding irreducible representations of affine Hecke algebras. Basic knowledge of abstract algebra is enough to read one third of the book. Some knowledge of K-theory, algebraic group, and Kazhdan-Lusztig cell of Cexeter group is useful for the rest

  17. An intersectional approach to gender and leadership development:Juxtaposing critical understandings of multiple identities, the ontology of leadership, and discourses of diversity management

    OpenAIRE

    Calvard, Tom; Meliou, Elina

    2015-01-01

    This paper is chiefly concerned with critically articulating the conceptual relationships between potential multiple identity (dis)advantages facing women and the effectiveness of leadership development practices. Although leadership development has been systematically studied in recent years (e.g. Day, Fleenor, Atwater, Sturm, and McKee, 2014; Ely, Ibarra, and Kolb, 2011), much less is known about its relation to gender (Ely et al, 2011). Furthermore, even less has been written about leaders...

  18. A Practical Anodic and Cathodic Curve Intersection Model to Understand Multiple Corrosion Potentials of Fe-Based Glassy Alloys in OH- Contained Solutions.

    Science.gov (United States)

    Li, Y J; Wang, Y G; An, B; Xu, H; Liu, Y; Zhang, L C; Ma, H Y; Wang, W M

    2016-01-01

    A practical anodic and cathodic curve intersection model, which consisted of an apparent anodic curve and an imaginary cathodic line, was proposed to explain multiple corrosion potentials occurred in potentiodynamic polarization curves of Fe-based glassy alloys in alkaline solution. The apparent anodic curve was selected from the measured anodic curves. The imaginary cathodic line was obtained by linearly fitting the differences of anodic curves and can be moved evenly or rotated to predict the number and value of corrosion potentials.

  19. Standard model of knowledge representation

    Science.gov (United States)

    Yin, Wensheng

    2016-09-01

    Knowledge representation is the core of artificial intelligence research. Knowledge representation methods include predicate logic, semantic network, computer programming language, database, mathematical model, graphics language, natural language, etc. To establish the intrinsic link between various knowledge representation methods, a unified knowledge representation model is necessary. According to ontology, system theory, and control theory, a standard model of knowledge representation that reflects the change of the objective world is proposed. The model is composed of input, processing, and output. This knowledge representation method is not a contradiction to the traditional knowledge representation method. It can express knowledge in terms of multivariate and multidimensional. It can also express process knowledge, and at the same time, it has a strong ability to solve problems. In addition, the standard model of knowledge representation provides a way to solve problems of non-precision and inconsistent knowledge.

  20. Realizations of the canonical representation

    Indian Academy of Sciences (India)

    A characterisation of the maximal abelian subalgebras of the bounded operators on Hilbert space that are normalised by the canonical representation of the Heisenberg group is given. This is used to classify the perfect realizations of the canonical representation.

  1. Lenses – Light, Bodies and Representations. A paper on the optical device that enables visual perception through representation

    DEFF Research Database (Denmark)

    Rehder, Mads

    I will discuss the many unique lenses available to visual anthropological research and how a nuanced and differentiated view on them can be the key to understanding the complexity of the representations we, as visual anthropologist, are creating.......I will discuss the many unique lenses available to visual anthropological research and how a nuanced and differentiated view on them can be the key to understanding the complexity of the representations we, as visual anthropologist, are creating....

  2. Functional representations for quantized fields

    International Nuclear Information System (INIS)

    Jackiw, R.

    1988-01-01

    This paper provides information on Representing transformations in quantum theory bosonic quantum field theories: Schrodinger Picture; Represnting Transformations in Bosonic Quantum Field Theory; Two-Dimensional Conformal Transformations, Schrodinger picture representation, Fock space representation, Inequivalent Schrodinger picture representations; Discussion, Self-Dual and Other Models; Field Theory in de Sitter Space. Fermionic Quantum Field Theories: Schroedinger Picture; Schrodinger Picture Representation for Two-Dimensional; Conformal Transformations; Fock Space Dynamics in the Schrodinger Picture; Fock Space Evaluation of Anomalous Current and Conformal Commutators

  3. Harmonic Analysis and Group Representation

    CERN Document Server

    Figa-Talamanca, Alessandro

    2011-01-01

    This title includes: Lectures - A. Auslander, R. Tolimeri - Nilpotent groups and abelian varieties, M Cowling - Unitary and uniformly bounded representations of some simple Lie groups, M. Duflo - Construction de representations unitaires d'un groupe de Lie, R. Howe - On a notion of rank for unitary representations of the classical groups, V.S. Varadarajan - Eigenfunction expansions of semisimple Lie groups, and R. Zimmer - Ergodic theory, group representations and rigidity; and, Seminars - A. Koranyi - Some applications of Gelfand pairs in classical analysis.

  4. Development and Application of a Two-Tier Multiple-Choice Diagnostic Test for High School Students' Understanding of Cell Division and Reproduction

    Science.gov (United States)

    Sesli, Ertugrul; Kara, Yilmaz

    2012-01-01

    This study involved the development and application of a two-tier diagnostic test for measuring students' understanding of cell division and reproduction. The instrument development procedure had three general steps: defining the content boundaries of the test, collecting information on students' misconceptions, and instrument development.…

  5. Tool use induces complex and flexible plasticity of human body representations.

    Science.gov (United States)

    Longo, Matthew R; Serino, Andrea

    2012-08-01

    Plasticity of body representation fundamentally underpins human tool use. Recent studies have demonstrated remarkably complex plasticity of body representation in humans, showing that such plasticity (1) occurs flexibly across multiple time scales and (2) involves multiple body representations responding differently to tool use. Such findings reveal remarkable sophistication of body plasticity in humans, suggesting that Vaesen may overestimate the similarity of such mechanisms in humans and non-human primates.

  6. Naturalising Representational Content

    Science.gov (United States)

    Shea, Nicholas

    2014-01-01

    This paper sets out a view about the explanatory role of representational content and advocates one approach to naturalising content – to giving a naturalistic account of what makes an entity a representation and in virtue of what it has the content it does. It argues for pluralism about the metaphysics of content and suggests that a good strategy is to ask the content question with respect to a variety of predictively successful information processing models in experimental psychology and cognitive neuroscience; and hence that data from psychology and cognitive neuroscience should play a greater role in theorising about the nature of content. Finally, the contours of the view are illustrated by drawing out and defending a surprising consequence: that individuation of vehicles of content is partly externalist. PMID:24563661

  7. Higher Representations Duals

    DEFF Research Database (Denmark)

    Sannino, Francesco

    2010-01-01

    We uncover novel solutions of the 't Hooft anomaly matching conditions for scalarless gauge theories with matter transforming according to higher dimensional representations of the underlying gauge group. We argue that, if the duals exist, they are gauge theories with fermions transforming accord......-Dyson approximation. We use the solutions to gain useful insight on the conformal window of the associated electric theory. A consistent picture emerges corroborating previous results obtained via different analytic methods and in agreement with first principle lattice explorations....

  8. The Knowledge Representation Project

    Science.gov (United States)

    1989-07-01

    representing k nowledge. I,- ONE was designed to represent the kinds of knowlodge constriicts encountered by developers of natural language processing systems...project called Empirically Valid Knowledge Representation in 1986. One of the first tasks of the new project was to translate NIKL into Common LISP -- a...constraints -- the syntactic structures that appear in LOO% :constraints or implies clauses translate into knowledge structures for which we have

  9. Representation of Knowledge

    Science.gov (United States)

    1980-03-01

    methodology involves the design of programs that exhibit Intelligent behavior, Al researchers have often taken a rather pragmatic approach to the subject...This article has not been about representation formalisms per se, but rather about the pragmatics of epistemology, the study of the nature of knowledge...1977. Levels of complexity In discourse for anaphora disambiguation and speech act interpretation. IJCAI 3, 43-49. Carbonell, J. R. 1970. Al in CAI: An

  10. Compact Information Representations

    Science.gov (United States)

    2016-08-02

    information representations, for solving very large-scale engineering problems in data stream computations, real-time network monitoring & anomaly...algorithms. Under the support of this AFOSR grant, a lot of excited research problems have been solved and many more arise. We will continue many...applied computer science, and applied math . Within the scope of this proposal, the focus is preliminarily on the fundamental, theoretical research

  11. Could representations influence strategy?

    OpenAIRE

    Diaz Ruiz, Carlos; Kowalkowski, Christian

    2014-01-01

    A central question in industrial marketing is whether the form in which the external environment of a firm is represented influences the marketing strategy. This influence has been studied generally through case study research, and quantitative evidence is limited. In response to this limitation, this paper reports on a quasi-experiment investigating whether market representations have a constructive aspect in business. Empirically, this study compares two types of ostensive and performative ...

  12. Non-Representational Theory

    DEFF Research Database (Denmark)

    Jensen, Ole B.

    2016-01-01

    Dette kapitel gennemgår den såkaldte ”Non-Representational Theory” (NRT), der primært er kendt fra den Angelsaksiske humangeografi, og som særligt er blevet fremført af den engelske geograf Nigel Thrift siden midten af 2000 årtiet. Da positionen ikke kan siges at være specielt homogen vil kapitlet...

  13. Representation Without Reconstruction

    OpenAIRE

    Edelman, Shimon

    1994-01-01

    According to the paradigmatic reconstructionist approach to vision, a visual system must first reconstruct the world internally, then extract from the resulting representation whatever features are necessary for the task at hand. Recent developments in computational vision and visual neuroscience show that many of the features needed for tasks ranging from spatial discrimination to object recognition can be extracted from the image directly, much as in Gibson's hypothesis of direct perception...

  14. Mental representations of arithmetic facts: evidence from eye movement recordings supports the preferred operand-order-specific representation hypothesis.

    Science.gov (United States)

    Zhou, Fan; Zhao, Qian; Chen, Chuansheng; Zhou, Xinlin

    2012-01-01

    There are three main hypotheses about mental representations of arithmetic facts: the independent representation hypothesis, the operand-order-free single-representation hypothesis, and the operand-order-specific single-representation hypothesis. The current study used electrical recordings of eye movements to examine the organization of arithmetic facts in long-term memory. Subjects were presented single-digit addition and multiplication problems and were asked to report the solutions. Analyses of the horizontal electrooculograph (HEOG) showed an operand order effect for multiplication in the time windows 150-300 ms (larger negative potentials for smaller operand first problems than for larger operand first ones). The operand order effect was reversed in the time windows from 400 to 1,000 ms (i.e., larger operand first problems had larger negative potentials than smaller operand first problems). For addition, larger operand first problems had larger negative potentials than smaller operand first in the series of time windows from 300 to 1,000 ms, but the effect was smaller than that for multiplication. These results confirmed the dissociated representation of addition and multiplication facts and were consistent with the prediction of the preferred operand-order-specific representation hypothesis.

  15. Effects of Computer-Based Visual Representation on Mathematics Learning and Cognitive Load

    Science.gov (United States)

    Yung, Hsin I.; Paas, Fred

    2015-01-01

    Visual representation has been recognized as a powerful learning tool in many learning domains. Based on the assumption that visual representations can support deeper understanding, we examined the effects of visual representations on learning performance and cognitive load in the domain of mathematics. An experimental condition with visual…

  16. Relations of Different Types of Numerical Magnitude Representations to Each Other and to Mathematics Achievement

    Science.gov (United States)

    Fazio, Lisa K.; Bailey, Drew H.; Thompson, Clarissa A.; Siegler, Robert S.

    2014-01-01

    We examined relations between symbolic and non-symbolic numerical magnitude representations, between whole number and fraction representations, and between these representations and overall mathematics achievement in fifth graders. Fraction and whole number symbolic and non-symbolic numerical magnitude understandings were measured using both…

  17. Metric representation of DNA sequences.

    Science.gov (United States)

    Wu, Z B

    2000-07-01

    A metric representation of DNA sequences is borrowed from symbolic dynamics. In view of this method, the pattern seen in the chaos game representation of DNA sequences is explained as the suppression of certain nucleotide strings in the DNA sequences. Frequencies of short nucleotide strings and suppression of the shortest ones in the DNA sequences can be determined by using the metric representation.

  18. Rethinking democracy and representation: a proposal to extend the democratic canon

    Directory of Open Access Journals (Sweden)

    Alejandro Monsiváis Carrillo

    2013-01-01

    Full Text Available Rethinking political representation is necessary to understand many contemporary democratic challenges. However, a widely accepted view states that democracy and representation are two irreconcilable principles, thus hindering the theoretical assessment of political representation's democratic relevance. According to this view, what democracy needs is more popular participation; instead, representation involves elitism and political detachment. In this paper I will argue that such a view is inaccurate. Through the reconstruction of the democratic ideal, and the discussion of the concept of political representation, I intend to show that processes of political authorization, accountability and public justification are both elements of political representation and expression of democratic politics.

  19. Mental Representations of Weekdays.

    Directory of Open Access Journals (Sweden)

    David A Ellis

    Full Text Available Keeping social appointments involves keeping track of what day it is. In practice, mismatches between apparent day and actual day are common. For example, a person might think the current day is Wednesday when in fact it is Thursday. Here we show that such mismatches are highly systematic, and can be traced to specific properties of their mental representations. In Study 1, mismatches between apparent day and actual day occurred more frequently on midweek days (Tuesday, Wednesday, and Thursday than on other days, and were mainly due to intrusions from immediately neighboring days. In Study 2, reaction times to report the current day were fastest on Monday and Friday, and slowest midweek. In Study 3, participants generated fewer semantic associations for "Tuesday", "Wednesday" and "Thursday" than for other weekday names. Similarly, Google searches found fewer occurrences of midweek days in webpages and books. Analysis of affective norms revealed that participants' associations were strongly negative for Monday, strongly positive for Friday, and graded over the intervening days. Midweek days are confusable because their mental representations are sparse and similar. Mondays and Fridays are less confusable because their mental representations are rich and distinctive, forming two extremes along a continuum of change.

  20. Pioneers of representation theory

    CERN Document Server

    Curtis, Charles W

    1999-01-01

    The year 1897 was marked by two important mathematical events: the publication of the first paper on representations of finite groups by Ferdinand Georg Frobenius (1849-1917) and the appearance of the first treatise in English on the theory of finite groups by William Burnside (1852-1927). Burnside soon developed his own approach to representations of finite groups. In the next few years, working independently, Frobenius and Burnside explored the new subject and its applications to finite group theory. They were soon joined in this enterprise by Issai Schur (1875-1941) and some years later, by Richard Brauer (1901-1977). These mathematicians' pioneering research is the subject of this book. It presents an account of the early history of representation theory through an analysis of the published work of the principals and others with whom the principals' work was interwoven. Also included are biographical sketches and enough mathematics to enable readers to follow the development of the subject. An introductor...

  1. Development of a representational conceptual evaluation in the first law of thermodynamics

    Science.gov (United States)

    Sriyansyah, S. P.; Suhandi, A.

    2016-08-01

    As part of an ongoing research to investigate student consistency in understanding the first law of thermodynamics, a representational conceptual evaluation (RCET) has been developed to assess student conceptual understanding, representational consistency, and scientific consistency in the introductory physics course. Previous physics education research findings were used to develop the test. RCET items were 30 items which designed as an isomorphic multiple-choice test with three different representations concerning the concept of work, heat, first law of thermodynamics, and its application in the thermodynamic processes. Here, we present preliminary measures of the validity and reliability of the instrument, including the classical test statistics. This instrument can be used to measure the intended concept in the first law of thermodynamics and it will give the consistent results with the ability to differentiate well between high-achieving students and low-achieving students and also students at different level. As well as measuring the effectiveness of the learning process in the concept of the first law of thermodynamics.

  2. Visualization Through Knowledge Representation Model for Social Networks

    DEFF Research Database (Denmark)

    Hussain, Dil Muhammad Akbar; Athar Javed, Muhammad; Ahmed, Zaki

    2011-01-01

    the process of knowing, learning and creating knowledge is the relevant aspect (Nonaka and Takeuchi 1995). In this paper knowledge representation is presented in 3D style for the understanding and visualization of dynamics of complex social networks by developing a TANetworkTool (Task Analysis Network Tool......). The standard or normal representation of a typical social network is through a graph data structure in 2D. The dynamics of larger social networks is so complex some time it becomes difficult to understand the various levels of interactions and dependencies just by mere representation through a tree or graph...... of complex social networks and complimenting the analytical results. This representation can also help authorities not necessarily having specific scientific background to understand and perhaps take preventive actions required in certain specific scenarios for example dealing with terrorist/covert networks....

  3. Using Multiple-hierarchy Stratification and Life Course Approaches to Understand Health Inequalities: The Intersecting Consequences of Race, Gender, SES, and Age.

    Science.gov (United States)

    Brown, Tyson H; Richardson, Liana J; Hargrove, Taylor W; Thomas, Courtney S

    2016-06-01

    This study examines how the intersecting consequences of race-ethnicity, gender, socioeconomics status (SES), and age influence health inequality. We draw on multiple-hierarchy stratification and life course perspectives to address two main research questions. First, does racial-ethnic stratification of health vary by gender and/or SES? More specifically, are the joint health consequences of racial-ethnic, gender, and socioeconomic stratification additive or multiplicative? Second, does this combined inequality in health decrease, remain stable, or increase between middle and late life? We use panel data from the Health and Retirement Study (N = 12,976) to investigate between- and within-group differences in in self-rated health among whites, blacks, and Mexican Americans. Findings indicate that the effects of racial-ethnic, gender, and SES stratification are interactive, resulting in the greatest racial-ethnic inequalities in health among women and those with higher levels of SES. Furthermore, racial-ethnic/gender/SES inequalities in health tend to decline with age. These results are broadly consistent with intersectionality and aging-as-leveler hypotheses. © American Sociological Association 2016.

  4. Understanding Consistent Condom Use Among Homeless Men Who Have Sex with Women and Engage in Multiple Sexual Partnerships: A Path Analysis.

    Science.gov (United States)

    Hsu, Hsun-Ta; Wenzel, Suzanne; Rice, Eric; Gilreath, Tamika D; Kurzban, Seth; Unger, Jennifer

    2015-09-01

    Consistent condom use is the main strategy aimed at preventing individuals from acquiring HIV through sexual intercourse. The mechanism of consistent condom use among a high-risk homeless subpopulation-homeless men who have sex with women and also engage in multiple sexual partnerships-remains unclear. This study identified 182 homeless men who engaged in multiple sexual partnerships from a representative sample of homeless men, who self-identified as heterosexual, using meal line services in Downtown Los Angeles' Skid Row area. Information such as participants' condom use psychosocial correlates, sexual risk behaviors, and social network characteristics were collected. Results suggested that condom efficacy is a potential intervening mechanism through which condom attitudes (β = -0.199; p = 0.005) and depression (β = -0.156; p = 0.029) are associated with an individual's consistent condom use. Having more network members with whom participants talked about HIV prevention (β = 0.051; p = 0.006) was also found to be associated with an individual's consistent condom use. HIV prevention programs should focus on increasing their condom efficacy to help reduce HIV risks among this vulnerable homeless subpopulation.

  5. Understanding the multiple magnetic structures of the intermetallic compound NdMn{sub 1.4}Co{sub 0.6}Si{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Halder, Madhumita, E-mail: mhalder@phy.iitb.ac.in [Department of Physics, Indian Institute of Technology Bombay, Mumbai 400076 (India); Bera, A.K.; Kumar, Amit [Solid State Physics Division, Bhabha Atomic Research Centre, Mumbai 400085 (India); Keller, L. [Laboratory for Neutron Scattering, Paul Scherrer Institut, CH-5232 Villigen PSI (Switzerland); Yusuf, S.M., E-mail: smyusuf@barc.gov.in [Solid State Physics Division, Bhabha Atomic Research Centre, Mumbai 400085 (India)

    2014-04-01

    Highlights: • Multiple magnetic phases of NdMn{sub 1.4}Co{sub 0.6}Si{sub 2} compound have been investigated. • Five distinct magnetic phases are found with temperature. • Collinear AFM, incommensurate AFM, mixed FM and AFM structures found. • Nd site contributes distinctly to the observed magnetic phases at low temperature. - Abstract: Magnetic phases for the intermetallic compound NdMn{sub 1.4}Co{sub 0.6}Si{sub 2} have been investigated at various temperatures by dc magnetization, neutron diffraction and neutron depolarization. Our study shows multiple magnetic phase transitions with temperature (T) over 1.5–300 K. In agreement with dc-magnetization and neutron depolarization results, the temperature dependence of the neutron diffraction patterns shows five distinct regions with different magnetic phases. These temperature regions are (i) T ⩾ 215 K, (ii) 215 K > T ⩾ 50 K, (iii) 50 K > T ⩾ 40 K, (iv) 40 K > T > 15 K, and (v) T ⩽ 15 K. The corresponding magnetic structures are paramagnetic, commensurate collinear antiferromagnetic (AFM-I), incommensurate AFM (AFM-II), mixed ferromagnetic and AFM (FM + AFM-II), and incommensurate AFM (AFM-II), respectively.

  6. Context Representation and Fusion: Advancements and Opportunities

    Directory of Open Access Journals (Sweden)

    Asad Masood Khattak

    2014-05-01

    Full Text Available The acceptance and usability of context-aware systems have given them the edge of wide use in various domains and has also attracted the attention of researchers in the area of context-aware computing. Making user context information available to such systems is the center of attention. However, there is very little emphasis given to the process of context representation and context fusion which are integral parts of context-aware systems. Context representation and fusion facilitate in recognizing the dependency/relationship of one data source on another to extract a better understanding of user context. The problem is more critical when data is emerging from heterogeneous sources of diverse nature like sensors, user profiles, and social interactions and also at different timestamps. Both the processes of context representation and fusion are followed in one way or another; however, they are not discussed explicitly for the realization of context-aware systems. In other words most of the context-aware systems underestimate the importance context representation and fusion. This research has explicitly focused on the importance of both the processes of context representation and fusion and has streamlined their existence in the overall architecture of context-aware systems’ design and development. Various applications of context representation and fusion in context-aware systems are also highlighted in this research. A detailed review on both the processes is provided in this research with their applications. Future research directions (challenges are also highlighted which needs proper attention for the purpose of achieving the goal of realizing context-aware systems.

  7. Context Representation and Fusion: Advancements and Opportunities

    Science.gov (United States)

    Khattak, Asad Masood; Akbar, Noman; Aazam, Mohammad; Ali, Taqdir; Khan, Adil Mehmood; Jeon, Seokhee; Hwang, Myunggwon; Lee, Sungyoung

    2014-01-01

    The acceptance and usability of context-aware systems have given them the edge of wide use in various domains and has also attracted the attention of researchers in the area of context-aware computing. Making user context information available to such systems is the center of attention. However, there is very little emphasis given to the process of context representation and context fusion which are integral parts of context-aware systems. Context representation and fusion facilitate in recognizing the dependency/relationship of one data source on another to extract a better understanding of user context. The problem is more critical when data is emerging from heterogeneous sources of diverse nature like sensors, user profiles, and social interactions and also at different timestamps. Both the processes of context representation and fusion are followed in one way or another; however, they are not discussed explicitly for the realization of context-aware systems. In other words most of the context-aware systems underestimate the importance context representation and fusion. This research has explicitly focused on the importance of both the processes of context representation and fusion and has streamlined their existence in the overall architecture of context-aware systems’ design and development. Various applications of context representation and fusion in context-aware systems are also highlighted in this research. A detailed review on both the processes is provided in this research with their applications. Future research directions (challenges) are also highlighted which needs proper attention for the purpose of achieving the goal of realizing context-aware systems. PMID:24887042

  8. Understanding uncertainty in process-based hydrological models

    Science.gov (United States)

    Clark, M. P.; Kavetski, D.; Slater, A. G.; Newman, A. J.; Marks, D. G.; Landry, C.; Lundquist, J. D.; Rupp, D. E.; Nijssen, B.

    2013-12-01

    Building an environmental model requires making a series of decisions regarding the appropriate representation of natural processes. While some of these decisions can already be based on well-established physical understanding, gaps in our current understanding of environmental dynamics, combined with incomplete knowledge of properties and boundary conditions of most environmental systems, make many important modeling decisions far more ambiguous. There is consequently little agreement regarding what a 'correct' model structure is, especially at relatively larger spatial scales such as catchments and beyond. In current practice, faced with such a range of decisions, different modelers will generally make different modeling decisions, often on an ad hoc basis, based on their balancing of process understanding, the data available to evaluate the model, the purpose of the modeling exercise, and their familiarity with or investment in an existing model infrastructure. This presentation describes development and application of multiple-hypothesis models to evaluate process-based hydrologic models. Our numerical model uses robust solutions of the hydrology and thermodynamic governing equations as the structural core, and incorporates multiple options to represent the impact of different modeling decisions, including multiple options for model parameterizations (e.g., below-canopy wind speed, thermal conductivity, storage and transmission of liquid water through soil, etc.), as well as multiple options for model architecture, that is, the coupling and organization of different model components (e.g., representations of sub-grid variability and hydrologic connectivity, coupling with groundwater, etc.). Application of this modeling framework across a collection of different research basins demonstrates that differences among model parameterizations are often overwhelmed by differences among equally-plausible model parameter sets, while differences in model architecture lead

  9. Multimodos e múltiplas Representações, aprendizagem significativa e subjetividade: três referenciais conciliáveis da educação científica Multimodal and multiple representation, significant learning and subjectivity: three reconcilable scientific education frameworks

    Directory of Open Access Journals (Sweden)

    Carlos Eduardo Laburú

    2011-01-01

    Full Text Available A linha de pesquisa em multimodos e múltiplas representações vem atualmente sendo inspiradora de ações instrucionais na educação científica. Partindo dos fundamentos que justificam um encaminhamento didático à luz dessas referências, este trabalho procura mostrar que há compatibilidade dos seus fundamentos com a teoria da aprendizagem significativa de Ausubel e com as questões levantadas pelas pesquisas que indicam a necessidade de se considerar a subjetividade dos alunos presentes numa sala de aula. Essencialmente, procuramos argumentar que a promoção de um ensino por meio de multimodos e múltiplas representações é consistente com o ambiente plural das subjetividades existentes numa sala de aula e com uma aprendizagem significativa.The research line in multi-modal and multiple representations is being currently inspiring instruction of actions in the scientific education. Starting by the foundations that justify a didactic direction in the light of theses references, this work tries to show that there is compatibility of their foundations with the theory of the significant learning of Ausubel, and with the lifted up subjects for the researches that indicate the need to consider the students' subjective diversity present in a classroom. Essentially, we tried to argue that the promotion of a teaching through multiple and multi-modal representation is consistent with the plural atmosphere of the existent subjectivities in a classroom and with a significant learning.

  10. Using SVG and XSLT for graphic representation

    OpenAIRE

    Baravalle, Andres; Lanfranchi, Vitaveska; Gribaudo, Marco

    2003-01-01

    Using SVG and XSLT for graphic representation\\ud In this paper we will present an XML based framework that can be used to produce graphical visualisation of scientific data. The approach rather than producing ordinary histogram and function diagaram graphs, tries to represent the information in a more graphical appealing and easy to understand way. For examples the approach will give the ability to represent the temperature as the level of coulored fluid in a thermometer.\\ud \\ud The proposed ...

  11. Representation of speech variability.

    Science.gov (United States)

    Bent, Tessa; Holt, Rachael F

    2017-07-01

    Speech signals provide both linguistic information (e.g., words and sentences) as well as information about the speaker who produced the message (i.e., social-indexical information). Listeners store highly detailed representations of these speech signals, which are simultaneously indexed with linguistic and social category membership. A variety of methodologies-forced-choice categorization, rating, and free classification-have shed light on listeners' cognitive-perceptual representations of the social-indexical information present in the speech signal. Specifically, listeners can accurately identify some talker characteristics, including native language status, approximate age, sex, and gender. Additionally, listeners have sensitivity to other speaker characteristics-such as sexual orientation, regional dialect, native language for non-native speakers, race, and ethnicity-but listeners tend to be less accurate or more variable at categorizing or rating speakers based on these constructs. However, studies have not necessarily incorporated more recent conceptions of these constructs (e.g., separating listeners' perceptions of race vs ethnicity) or speakers who do not fit squarely into specific categories (e.g., for sex perception, intersex individuals; for gender perception, genderqueer speakers; for race perception, multiracial speakers). Additional research on how the intersections of social-indexical categories influence speech perception is also needed. As the field moves forward, scholars from a variety of disciplines should be incorporated into investigations of how listeners' extract and represent facets of personal identity from speech. Further, the impact of these representations on our interactions with one another in contexts outside of the laboratory should continue to be explored. WIREs Cogn Sci 2017, 8:e1434. doi: 10.1002/wcs.1434 This article is categorized under: Linguistics > Language Acquisition Linguistics > Language in Mind and Brain Psychology

  12. Generative Representations for Evolving Families of Designs

    Science.gov (United States)

    Hornby, Gregory S.

    2003-01-01

    Since typical evolutionary design systems encode only a single artifact with each individual, each time the objective changes a new set of individuals must be evolved. When this objective varies in a way that can be parameterized, a more general method is to use a representation in which a single individual encodes an entire class of artifacts. In addition to saving time by preventing the need for multiple evolutionary runs, the evolution of parameter-controlled designs can create families of artifacts with the same style and a reuse of parts between members of the family. In this paper an evolutionary design system is described which uses a generative representation to encode families of designs. Because a generative representation is an algorithmic encoding of a design, its input parameters are a way to control aspects of the design it generates. By evaluating individuals multiple times with different input parameters the evolutionary design system creates individuals in which the input parameter controls specific aspects of a design. This system is demonstrated on two design substrates: neural-networks which solve the 3/5/7-parity problem and three-dimensional tables of varying heights.

  13. Representations of commonsense knowledge

    CERN Document Server

    Davis, Ernest

    1990-01-01

    Representations of Commonsense Knowledge provides a rich language for expressing commonsense knowledge and inference techniques for carrying out commonsense knowledge. This book provides a survey of the research on commonsense knowledge.Organized into 10 chapters, this book begins with an overview of the basic ideas on artificial intelligence commonsense reasoning. This text then examines the structure of logic, which is roughly analogous to that of a programming language. Other chapters describe how rules of universal validity can be applied to facts known with absolute certainty to deduce ot

  14. Representations from the past

    DEFF Research Database (Denmark)

    Sammut, Gordon; Tsirogianni, Stavroula; Wagoner, Brady

    2012-01-01

    a deconstructive effort that maps the evolutionary trajectory of a representational project in terms of its adaptation over time. We go on to illustrate our proposal visiting data that emerged in an inquiry investigating Maltese immigrants’ perspectives towards their countries of settlement and origin. This data...... explain how Maltese immigrants to Britain opt for certain forms of intercultural relations than others that are normally Integr preferable. We demonstrate that these preferences rely on an evolved justification of the Maltese getting by with foreign rulers that other scholars have traced back...

  15. Surveyable Representations, the "Lecture on Ethics", and Moral Philosophy

    Directory of Open Access Journals (Sweden)

    Benjamin De Mesel

    2014-12-01

    Full Text Available I argue that it is possible and useful for moral philosophy to provide surveyable representations (as the later Wittgenstein understands the concept of moral vocabulary. I proceed in four steps. First, I present two dominant interpretations of the concept “surveyable representation”. Second, I use these interpretations as a background against which I present my own interpretation. Third, I use my interpretation to support the claim that Wittgenstein’s “Lecture on Ethics” counts as an example of a surveyable representation. I conclude that, since the lecture qualifies as a surveyable representation, it is possible to provide surveyable representations of moral vocabulary. Fourth, I argue that it is useful for contemporary moral philosophy to provide surveyable representations, because it may help to dissolve problems in current debates. I provide an example of such a debate, namely, the debate between cognitivists and non-cognivitists.

  16. Understanding the transport and fate of multiple pollutants: development and testing of a coupled surface-groundwater flow and water quality model

    Science.gov (United States)

    Sinha, Sumit; Wade, Andrew

    2017-04-01

    The problem of river pollutant diversity, especially in the south-east of UK, is typically associated with sediment, nutrients and micro-organic chemicals such as pesticides. The pollution problem is further exacerbated by climate change and population growth. Given this policy makers and environmental regulators need catchment scale water quantity and quality model that could be potentially used to assess multiple pollutants in catchments with a large groundwater contribution. The research presented here details development of a spatially explicit, coupled surface- groundwater model and its application in an exemplar lowland catchment in the south-east of UK with extensive surface and groundwater datasets available. More specifically, the fully distributed mesoscale hydrological model (mHM) is coupled with MODFLOW in the Enborne catchment (150 km2). Simulations are conducted on daily time step with spatial resolution of 1 km2 grid cell between 1970 and 2010. The spatially explicit nature of the modelling framework is being used to explore aquifer recharge and water and solute residence times to ultimately explore the lags between changes to pollutant loadings, the introduction of small-scale pollution control measures and the within stream response.

  17. Social Representations of Intelligence

    Directory of Open Access Journals (Sweden)

    Elena Zubieta

    2016-02-01

    Full Text Available The article stresses the relationship between Explicit and Implicit theories of Intelligence. Following the line of common sense epistemology and the theory of Social Representations, a study was carried out in order to analyze naive’s explanations about Intelligence Definitions. Based on Mugny & Carugati (1989 research, a self-administered questionnaire was designed and filled in by 286 subjects. Results are congruent with the main hyphotesis postulated: A general overlap between explicit and implicit theories showed up. According to the results Intelligence appears as both, a social attribute related to social adaptation and as a concept defined in relation with contextual variables similar to expert’s current discourses. Nevertheless, conceptions based on “gifted ideology” still are present stressing the main axes of Intelligence debate: biological and sociological determinism. In the same sense, unfamiliarity and social identity are reaffirmed as organizing principles of social representation. The distance with the object -measured as the belief in intelligence differences as a solve/non solve problem- and the level of implication with the topic -teachers/no teachers- appear as discriminating elements at the moment of supporting specific dimensions. 

  18. On functional representations of the conformal algebra

    Energy Technology Data Exchange (ETDEWEB)

    Rosten, Oliver J.

    2017-07-15

    Starting with conformally covariant correlation functions, a sequence of functional representations of the conformal algebra is constructed. A key step is the introduction of representations which involve an auxiliary functional. It is observed that these functionals are not arbitrary but rather must satisfy a pair of consistency equations corresponding to dilatation and special conformal invariance. In a particular representation, the former corresponds to the canonical form of the exact renormalization group equation specialized to a fixed point whereas the latter is new. This provides a concrete understanding of how conformal invariance is realized as a property of the Wilsonian effective action and the relationship to action-free formulations of conformal field theory. Subsequently, it is argued that the conformal Ward Identities serve to define a particular representation of the energy-momentum tensor. Consistency of this construction implies Polchinski's conditions for improving the energy-momentum tensor of a conformal field theory such that it is traceless. In the Wilsonian approach, the exactly marginal, redundant field which generates lines of physically equivalent fixed points is identified as the trace of the energy-momentum tensor. (orig.)

  19. Audio Spatial Representation Around the Body.

    Science.gov (United States)

    Aggius-Vella, Elena; Campus, Claudio; Finocchietti, Sara; Gori, Monica

    2017-01-01

    Studies have found that portions of space around our body are differently coded by our brain. Numerous works have investigated visual and auditory spatial representation, focusing mostly on the spatial representation of stimuli presented at head level, especially in the frontal space. Only few studies have investigated spatial representation around the entire body and its relationship with motor activity. Moreover, it is still not clear whether the space surrounding us is represented as a unitary dimension or whether it is split up into different portions, differently shaped by our senses and motor activity. To clarify these points, we investigated audio localization of dynamic and static sounds at different body levels. In order to understand the role of a motor action in auditory space representation, we asked subjects to localize sounds by pointing with the hand or the foot, or by giving a verbal answer. We found that the audio sound localization was different depending on the body part considered. Moreover, a different pattern of response was observed when subjects were asked to make actions with respect to the verbal responses. These results suggest that the audio space around our body is split in various spatial portions, which are perceived differently: front, back, around chest, and around foot, suggesting that these four areas could be differently modulated by our senses and our actions.

  20. Accurate metacognition for visual sensory memory representations.

    Science.gov (United States)

    Vandenbroucke, Annelinde R E; Sligte, Ilja G; Barrett, Adam B; Seth, Anil K; Fahrenfort, Johannes J; Lamme, Victor A F

    2014-04-01

    The capacity to attend to multiple objects in the visual field is limited. However, introspectively, people feel that they see the whole visual world at once. Some scholars suggest that this introspective feeling is based on short-lived sensory memory representations, whereas others argue that the feeling of seeing more than can be attended to is illusory. Here, we investigated this phenomenon by combining objective memory performance with subjective confidence ratings during a change-detection task. This allowed us to compute a measure of metacognition--the degree of knowledge that subjects have about the correctness of their decisions--for different stages of memory. We show that subjects store more objects in sensory memory than they can attend to but, at the same time, have similar metacognition for sensory memory and working memory representations. This suggests that these subjective impressions are not an illusion but accurate reflections of the richness of visual perception.

  1. Multiple Intelligences for Differentiated Learning

    Science.gov (United States)

    Williams, R. Bruce

    2007-01-01

    There is an intricate literacy to Gardner's multiple intelligences theory that unlocks key entry points for differentiated learning. Using a well-articulated framework, rich with graphic representations, Williams provides a comprehensive discussion of multiple intelligences. He moves the teacher and students from curiosity, to confidence, to…

  2. The Theory of Social Representations, his application in the studies of health and disease: the case of the obesity

    OpenAIRE

    Yurimay Quintero; Jauri Villarroel; Luz Pargas; Gladys Bastardo; Coromoto Angarita; José Gregorio Rivas; Gabriel Castañeda

    2016-01-01

    Introduction: The social representations about health are the result of the articulation between representations and experiences about health practices. Analyzing the problem of obesity from the perspective of social representations would allow us to understand this issue from an approach that has not been tackled until now. To analyze the problem of obesity from Social Representations viewpoint would enable us to understand it with great potential from an approach that has not been used unti...

  3. Integrating multiple lines of evidence to better understand the evolutionary divergence of humpback dolphins along their entire distribution range: a new dolphin species in Australian waters?

    Science.gov (United States)

    Mendez, Martin; Jefferson, Thomas A; Kolokotronis, Sergios-Orestis; Krützen, Michael; Parra, Guido J; Collins, Tim; Minton, Giana; Baldwin, Robert; Berggren, Per; Särnblad, Anna; Amir, Omar A; Peddemors, Vic M; Karczmarski, Leszek; Guissamulo, Almeida; Smith, Brian; Sutaria, Dipani; Amato, George; Rosenbaum, Howard C

    2013-12-01

    The conservation of humpback dolphins, distributed in coastal waters of the Indo-West Pacific and eastern Atlantic Oceans, has been hindered by a lack of understanding about the number of species in the genus (Sousa) and their population structure. To address this issue, we present a combined analysis of genetic and morphologic data collected from beach-cast, remote-biopsied and museum specimens from throughout the known Sousa range. We extracted genetic sequence data from 235 samples from extant populations and explored the mitochondrial control region and four nuclear introns through phylogenetic, population-level and population aggregation frameworks. In addition, 180 cranial specimens from the same geographical regions allowed comparisons of 24 morphological characters through multivariate analyses. The genetic and morphological data showed significant and concordant patterns of geographical segregation, which are typical for the kind of demographic isolation displayed by species units, across the Sousa genus distribution range. Based on our combined genetic and morphological analyses, there is convincing evidence for at least four species within the genus (S. teuszii in the Atlantic off West Africa, S. plumbea in the central and western Indian Ocean, S. chinensis in the eastern Indian and West Pacific Oceans, and a new as-yet-unnamed species off northern Australia). © 2013 John Wiley & Sons Ltd.

  4. Indicators that influence prospective mathematics teachers representational and reasoning abilities

    Science.gov (United States)

    Darta; Saputra, J.

    2018-01-01

    Representational and mathematical reasoning ability are very important ability as basic in mathematics learning process. The 2013 curriculum suggests that the use of a scientific approach emphasizes higher order thinking skills. Therefore, a scientific approach is required in mathematics learning to improve ability of representation and mathematical reasoning. The objectives of this research are: (1) to analyze representational and reasoning abilities, (2) to analyze indicators affecting the ability of representation and mathematical reasoning, (3) to analyze scientific approaches that can improve the ability of representation and mathematical reasoning. The subject of this research is the students of mathematics prospective teachers in the first semester at Private Higher Education of Bandung City. The research method of this research was descriptive analysis. The research data were collected using reasoning and representation tests on sixty-one students. Data processing was done by descriptive analysis specified based on the indicators of representation ability and mathematical reasoning that influenced it. The results of this first-year study showed that students still had many weaknesses in reasoning and mathematical representation that were influenced by the ability to understand the indicators of both capabilities. After observing the results of the first-year research, then in the second and third year, the development of teaching materials with a scientific approach in accordance with the needs of prospective students was planned.

  5. Using Survival Analysis to Understand Patterns of Sustainment within a System-Driven Implementation of Multiple Evidence-Based Practices for Children’s Mental Health Services

    Directory of Open Access Journals (Sweden)

    Lauren Brookman-Frazee

    2018-03-01

    the six EBPs. This study illustrates a novel application of survival analysis to administrative claims data in system-driven implementation of multiple EBPs. Findings reveal variability in the long-term continuation of therapist-level delivery of EBPs and highlight the importance of both agency and workforce characteristics in the sustained delivery of EBPs. Findings direct the field to potential targets of sustainment interventions (e.g., strategic assignment of therapists to EBP training and strategic selection of EBPs by agencies.

  6. Linear representation of a graph

    Directory of Open Access Journals (Sweden)

    Eduardo Montenegro

    2019-10-01

    Full Text Available In this paper the linear representation of a graph is defined. A linear representation of a graph is a subgroup of $GL(p,\\mathbb{R}$, the group of invertible matrices of order $ p $ and real coefficients. It will be demonstrated that every graph admits a linear representation. In this paper, simple and finite graphs will be used, framed in the graphs theory's area

  7. Blocks of tame representation type and related algebras

    CERN Document Server

    Erdmann, Karin

    1990-01-01

    This monograph studies algebras that are associated to blocks of tame representation type. Over the past few years, a range of new results have been obtained and a comprehensive account of these is provided here to- gether with some new proofs of known results. Some general theory of algebras is also presented, as a means of understanding the subject. The book is addressed to researchers and graduate students interested in the links between representations of finite-dimensional algebras and modular group representation theory. The basic properties of modules and finite-dimensional algebras are assumed known.

  8. POC caster: Broadcasting Agent Using Conversational Representation for Internet Community

    Science.gov (United States)

    Kubota, Hidekazu; Yamashita, Kouji; Fukuhara, Tomohiro; Nishida, Toyoaki

    We propose a broadcating agent system called {\\it POC caster} that generates understandable conversational representation from heterogeneous text-based opinions. POC caster introduces an opinion of a community member by a conversational method in Public Opinion Channel(POC) that is an interactive broadcasting system supporting community knowledge creation. The way to generate conversational representation from an opinion is consist of two processes. The first process is an analysis of an intention of the opinion by referring the last word of a sentence. The second process is applying some rules about intentions and positions of the sentences to make an understandable conversation. The psychological experiments about understandability of generated conversations are described.

  9. Sinusoidal Representation of Acoustic Signals

    Science.gov (United States)

    Honda, Masaaki

    Sinusoidal representation of acoustic signals has been an important tool in speech and music processing like signal analysis, synthesis and time scale or pitch modifications. It can be applicable to arbitrary signals, which is an important advantage over other signal representations like physical modeling of acoustic signals. In sinusoidal representation, acoustic signals are composed as sums of sinusoid (sine wave) with different amplitudes, frequencies and phases, which is based on the timedependent short-time Fourier transform (STFT). This article describes the principles of acoustic signal analysis/synthesis based on a sinusoid representation with focus on sine waves with rapidly varying frequency.

  10. Social representation of healthy aging for elder men

    Directory of Open Access Journals (Sweden)

    Ludgleydson Fernandes de Araújo

    2012-09-01

    Full Text Available This study aimed to understand the social representations of aging in healthy older men Parnaíba (PI. The sample was random, accidental and intentional, consisting of 50 elderly (M=72 years. Was used as an instrument of data collection structured interview. Data analysis was performed by a software Alceste. The representations of elderly extended beyond making an organismic conception affective aspects, interactional and politicians.

  11. Intentionality, Representation, and Anticipation

    Science.gov (United States)

    De Preester, Helena

    2002-09-01

    Both Brentano and Merleau-Ponty have developed an account of intentionality, which nevertheless differ profoundly in the following respect. According to Brentano, intentionality mainly is a matter of mental presentations. This marks the beginning of phenomenology's difficult relation with the nature of the intentional reference. Merleau-Ponty, on the other hand, has situated intentionality on the level of the body, a turn which has important implications for the nature of intentionality. Intentionality no longer is primarily based on having (re)presentations, but is rooted in the dynamics of the living body. To contrast those approaches enables us to make clear in what way intentionality is studied nowadays. On the one hand, intentionality is conceived of as a matter of formal-syntactical causality in cognitive science, and in particular in classical-computational theory. On the other hand, a interactivist approach offers a more Merleau-Ponty-like point of view, in which autonomy, embodiment and interaction are stressed.

  12. Research in Knowledge Representation for Natural Language Understanding

    Science.gov (United States)

    1980-02-28

    been adequately studied in the past. One of these is the need for situation dependent interpretation of linguistic devices such as deixis and... deixis involves such references to things that have not been said, but are present in some way in the non-linguistic context of the conversation (e.g...far fron solved), whereas deixis of the kind that occurs in the display context is considerably less well understood. The resolution of both deictic

  13. Looking beyond superficial knowledge gaps: understanding public representations of biodiversity

    NARCIS (Netherlands)

    Buijs, A.E.; Fischer, A.; Rink, D.; Young, J.C.

    2008-01-01

    Lack of public support for, and protest against, biodiversity management measures have often been explained by the apparently inadequate knowledge of biodiversity in the general public. In stark contrast to this assumption of public ignorance, our results from focus group discussions in The

  14. Preschool Children's Participation in Representational and Non-Representational Activities

    Science.gov (United States)

    Braswell, Gregory S.

    2017-01-01

    The present study examined representational and non-representational activities in which children in a Head Start classroom participated. This was an investigation from the perspective of cultural-historical activity theory of how components (e.g. artifacts and division of labour) of classroom activities vary across and within types of activities.…

  15. Probabilistic graphical model representation in phylogenetics.

    Science.gov (United States)

    Höhna, Sebastian; Heath, Tracy A; Boussau, Bastien; Landis, Michael J; Ronquist, Fredrik; Huelsenbeck, John P

    2014-09-01

    Recent years have seen a rapid expansion of the model space explored in statistical phylogenetics, emphasizing the need for new approaches to statistical model representation and software development. Clear communication and representation of the chosen model is crucial for: (i) reproducibility of an analysis, (ii) model development, and (iii) software design. Moreover, a unified, clear and understandable framework for model representation lowers the barrier for beginners and nonspecialists to grasp complex phylogenetic models, including their assumptions and parameter/variable dependencies. Graphical modeling is a unifying framework that has gained in popularity in the statistical literature in recent years. The core idea is to break complex models into conditionally independent distributions. The strength lies in the comprehensibility, flexibility, and adaptability of this formalism, and the large body of computational work based on it. Graphical models are well-suited to teach statistical models, to facilitate communication among phylogeneticists and in the development of generic software for simulation and statistical inference. Here, we provide an introduction to graphical models for phylogeneticists and extend the standard graphical model representation to the realm of phylogenetics. We introduce a new graphical model component, tree plates, to capture the changing structure of the subgraph corresponding to a phylogenetic tree. We describe a range of phylogenetic models using the graphical model framework and introduce modules to simplify the representation of standard components in large and complex models. Phylogenetic model graphs can be readily used in simulation, maximum likelihood inference, and Bayesian inference using, for example, Metropolis-Hastings or Gibbs sampling of the posterior distribution. © The Author(s) 2014. Published by Oxford University Press, on behalf of the Society of Systematic Biologists.

  16. Competition and Cooperation among Relational Memory Representations

    Science.gov (United States)

    Schwarb, Hillary; Watson, Patrick D.; Campbell, Kelsey; Shander, Christopher L.; Monti, Jim M.; Cooke, Gillian E.; Wang, Jane X.; Kramer, Arthur F.; Cohen, Neal J.

    2015-01-01

    Mnemonic processing engages multiple systems that cooperate and compete to support task performance. Exploring these systems’ interaction requires memory tasks that produce rich data with multiple patterns of performance sensitive to different processing sub-components. Here we present a novel context-dependent relational memory paradigm designed to engage multiple learning and memory systems. In this task, participants learned unique face-room associations in two distinct contexts (i.e., different colored buildings). Faces occupied rooms as determined by an implicit gender-by-side rule structure (e.g., male faces on the left and female faces on the right) and all faces were seen in both contexts. In two experiments, we use behavioral and eye-tracking measures to investigate interactions among different memory representations in both younger and older adult populations; furthermore we link these representations to volumetric variations in hippocampus and ventromedial PFC among older adults. Overall, performance was very accurate. Successful face placement into a studied room systematically varied with hippocampal volume. Selecting the studied room in the wrong context was the most typical error. The proportion of these errors to correct responses positively correlated with ventromedial prefrontal volume. This novel task provides a powerful tool for investigating both the unique and interacting contributions of these systems in support of relational memory. PMID:26619203

  17. Comparing the effects of representational tools in collaborative and individual inquiry learning

    NARCIS (Netherlands)

    Kolloffel, Bas Jan; Eysink, Tessa H.S.; de Jong, Anthonius J.M.

    2011-01-01

    Constructing a representation in which students express their domain understanding can help them improve their knowledge. Many different representational formats can be used to express one’s domain understanding (e.g., concept maps, textual summaries, mathematical equations). The format can direct

  18. Challenges in land model representation of heat transfer in snow and frozen soils

    Science.gov (United States)

    Musselman, K. N.; Clark, M. P.; Nijssen, B.; Arnold, J.

    2017-12-01

    Accurate model simulations of soil thermal and moisture states are critical for realistic estimates of exchanges of energy, water, and biogeochemical fluxes at the land-atmosphere interface. In cold regions, seasonal snow-cover and organic soils form insulating barriers, modifying the heat and moisture exchange that would otherwise occur between mineral soils and the atmosphere. The thermal properties of these media are highly dynamic functions of mass, water and ice content. Land surface models vary in their representation of snow and soil processes, and thus in the treatment of insulation and heat exchange. For some models, recent development efforts have improved representation of heat transfer in cold regions, such as with multi-layer snow treatment, inclusion of soil freezing and organic soil properties, yet model deficiencies remain prevalent. We evaluate models that participated in the Protocol for the Analysis of Land Surface Models (PALS) Land Surface Model Benchmarking Evaluation Project (PLUMBER) experiment for proficiency in simulating heat transfer between the soil through the snowpack to the atmosphere. Using soil observations from cold region sites and a controlled experiment with Structure for Unifying Multiple Modeling Alternatives (SUMMA), we explore the impact of snow and soil model decisions and parameter values on heat transfer model skill. Specifically, we use SUMMA to mimic the spread of behaviors exhibited by the models that participated in PLUMBER. The experiment allows us to isolate relationships between model skill and process representation. The results are aimed to better understand existing model challenges and identify potential advances for cold region models.

  19. Representations of the infinite symmetric group

    CERN Document Server

    Borodin, Alexei

    2016-01-01

    Representation theory of big groups is an important and quickly developing part of modern mathematics, giving rise to a variety of important applications in probability and mathematical physics. This book provides the first concise and self-contained introduction to the theory on the simplest yet very nontrivial example of the infinite symmetric group, focusing on its deep connections to probability, mathematical physics, and algebraic combinatorics. Following a discussion of the classical Thoma's theorem which describes the characters of the infinite symmetric group, the authors describe explicit constructions of an important class of representations, including both the irreducible and generalized ones. Complete with detailed proofs, as well as numerous examples and exercises which help to summarize recent developments in the field, this book will enable graduates to enhance their understanding of the topic, while also aiding lecturers and researchers in related areas.

  20. Introduction to the representation theory of algebras

    CERN Document Server

    Barot, Michael

    2015-01-01

    This book gives a general introduction to the theory of representations of algebras. It starts with examples of classification problems of matrices under linear transformations and explains the three common setups: representation of quivers, modules over algebras and additive functors over certain categories. The main part is devoted to (i) module categories, presenting the unicity of the decomposition into indecomposable modules, the Auslander–Reiten theory and the technique of knitting; (ii) the use of combinatorial tools such as dimension vectors and integral quadratic forms; and (iii) deeper theorems such as Gabriel‘s Theorem, the trichotomy and the Theorem of Kac – all accompanied by further examples. Each section includes exercises to facilitate understanding. By keeping the proofs as basic and comprehensible as possible and introducing the three languages at the beginning, this book is suitable for readers from the advanced undergraduate level onwards and enables them to consult related, specifi...

  1. On squares of representations of compact Lie algebras

    International Nuclear Information System (INIS)

    Zeier, Robert; Zimborás, Zoltán

    2015-01-01

    We study how tensor products of representations decompose when restricted from a compact Lie algebra to one of its subalgebras. In particular, we are interested in tensor squares which are tensor products of a representation with itself. We show in a classification-free manner that the sum of multiplicities and the sum of squares of multiplicities in the corresponding decomposition of a tensor square into irreducible representations has to strictly grow when restricted from a compact semisimple Lie algebra to a proper subalgebra. For this purpose, relevant details on tensor products of representations are compiled from the literature. Since the sum of squares of multiplicities is equal to the dimension of the commutant of the tensor-square representation, it can be determined by linear-algebra computations in a scenario where an a priori unknown Lie algebra is given by a set of generators which might not be a linear basis. Hence, our results offer a test to decide if a subalgebra of a compact semisimple Lie algebra is a proper one without calculating the relevant Lie closures, which can be naturally applied in the field of controlled quantum systems

  2. Revealing Children's Implicit Spelling Representations

    Science.gov (United States)

    Critten, Sarah; Pine, Karen J.; Messer, David J.

    2013-01-01

    Conceptualizing the underlying representations and cognitive mechanisms of children's spelling development is a key challenge for literacy researchers. Using the Representational Redescription model (Karmiloff-Smith), Critten, Pine and Steffler (2007) demonstrated that the acquisition of phonological and morphological knowledge may be underpinned…

  3. $\\alpha$-Representation for QCD

    OpenAIRE

    Tuan, Richard Hong

    1998-01-01

    An $\\alpha$-parameter representation is derived for gauge field theories.It involves, relative to a scalar field theory, only constants and derivatives with respect to the $\\alpha$-parameters. Simple rules are given to obtain the $\\alpha$-representation for a Feynman graph with an arbitrary number of loops in gauge theories in the Feynman gauge.

  4. Scientific Representation and Science Learning

    Science.gov (United States)

    Matta, Corrado

    2014-01-01

    In this article I examine three examples of philosophical theories of scientific representation with the aim of assessing which of these is a good candidate for a philosophical theory of scientific representation in science learning. The three candidate theories are Giere's intentional approach, Suárez's inferential approach and Lynch and…

  5. "Ladettes," Social Representations, and Aggression.

    Science.gov (United States)

    Muncer, Steven; Campbell, Anne; Jervis, Victoria; Lewis, Rachel

    2001-01-01

    Examined the relationship among "laddishness" (traditionally working-class, youthful, male social behavior by young women), social representations, and self-reported aggression among English college students. Measures of aggression correlated with holding more instrumental representations of aggression. Females indicated no relationship…

  6. Combinatorial representations of token sequences

    NARCIS (Netherlands)

    Elzinga, C.H.

    2005-01-01

    This paper presents new representations of token sequences, with and without associated quantities, in Euclidean space. The representations are free of assumptions about the nature of the sequences or the processes that generate them. Algorithms and applications from the domains of structured

  7. Fuzzy Morphological Polynomial Image Representation

    Directory of Open Access Journals (Sweden)

    Chin-Pan Huang

    2010-01-01

    Full Text Available A novel signal representation using fuzzy mathematical morphology is developed. We take advantage of the optimum fuzzy fitting and the efficient implementation of morphological operators to extract geometric information from signals. The new representation provides results analogous to those given by the polynomial transform. Geometrical decomposition of a signal is achieved by windowing and applying sequentially fuzzy morphological opening with structuring functions. The resulting representation is made to resemble an orthogonal expansion by constraining the results of opening to equate adapted structuring functions. Properties of the geometric decomposition are considered and used to calculate the adaptation parameters. Our procedure provides an efficient and flexible representation which can be efficiently implemented in parallel. The application of the representation is illustrated in data compression and fractal dimension estimation temporal signals and images.

  8. Archival Representation in the Digital Age

    Science.gov (United States)

    Zhang, Jane

    2012-01-01

    This study analyzes the representation systems of three digitized archival collections using the traditional archival representation framework of provenance, order, and content. The results of the study reveal a prominent role of provenance representation, a compromised role of order representation, and an active role of content representation in…

  9. Electrophysiology of action representation.

    Science.gov (United States)

    Fadiga, Luciano; Craighero, Laila

    2004-01-01

    We continuously act on objects, on other individuals, and on ourselves, and actions represent the only way we have to manifest our own desires and goals. In the last two decades, electrophysiological experiments have demonstrated that actions are stored in the brain according to a goal-related organization. The authors review a series of experimental data showing that this "vocabulary of motor schemata" could also be used for non-strictly motor purposes. In the first section, they present data from monkey experiments describing the functional properties of inferior premotor cortex and, in more detail, the properties of visuomotor neurons responding to objects and others' actions observation (mirror neurons). In the second section, human data are reviewed, with particular regard to electrophysiological experiments aiming to investigate how action representations are stored and addressed. The specific facilitatory effect of motor imagery, action/object observation, and speech listening on motor excitability shown by these experiments provides strong evidence that the motor system is constantly involved whenever the idea of an action is evoked.

  10. Chemical thermodynamic representation of

    International Nuclear Information System (INIS)

    Lindemer, T.B.; Besmann, T.M.

    1984-01-01

    The entire data base for the dependence of the nonstoichiometry, x, on temperature and chemical potential of oxygen (oxygen potential) was retrieved from the literature and represented. This data base was interpreted by least-squares analysis using equations derived from the classical thermodynamic theory for the solid solution of a solute in a solvent. For hyperstoichiometric oxide at oxygen potentials more positive than -266700 + 16.5T kJ/mol, the data were best represented by a [UO 2 ]-[U 3 O 7 ] solution. For O/U ratios above 2 and oxygen potentials below this boundary, a [UO 2 ]-[U 2 O 4 . 5 ] solution represented the data. The data were represented by a [UO 2 ]-[U 1 / 3 ] solution. The resulting equations represent the experimental ln(PO 2 ) - ln(x) behavior and can be used in thermodynamic calculations to predict phase boundary compositions consistent with the literature. Collectively, the present analysis permits a mathematical representation of the behavior of the total data base

  11. Islam and Media Representations

    Directory of Open Access Journals (Sweden)

    Mohamed Bensalah

    2006-04-01

    Full Text Available For the author of this article, the media’s treatment of Islam has raised numerous polymorphous questions and debates. Reactivated by the great scares of current events, the issue, though an ancient one, calls many things into question. By way of introduction, the author tries to analyse the complex processes of elaboration and perception of the representations that have prevailed during the past century. In referring to the semantic decoding of the abundant colonial literature and iconography, the author strives to translate the extreme xenophobic tensions and the identity crystallisations associated with the current media orchestration of Islam, both in theWest and the East. He then evokes the excesses of the media that are found at the origin of many amalgams wisely maintained between Islam, Islamism and Islamic terrorism, underscoring their duplicity and their willingness to put themselves, consciously, in service to deceivers and directors of awareness, who are very active at the heart of the politico-media sphere. After levelling a severe accusation against the harmful drifts of the media, especially in times of crisis and war, the author concludes by asserting that these tools of communication, once they are freed of their masks and invective apparatuses, can be re-appropriated by new words and bya true communication between peoples and cultures.

  12. Parent and child asthma illness representations: a systematic review.

    Science.gov (United States)

    Sonney, Jennifer T; Gerald, Lynn B; Insel, Kathleen C

    2016-06-01

    The purpose of this article is to synthesize the current literature on parent and child asthma illness representations and their consequent impact on parent-child asthma shared management. This systematic review was conducted in concordance with the PRISMA statement. An electronic search of five computerized databases (PubMed, PsycINFO, CINAHL, Cochrane, and EMBASE) was conducted using the following key words: asthma, illness representation, and child. Due to the limited number of articles identified, the search was broadened to include illness perceptions as well. Studies were included if they were specific to asthma and included parent and/or child asthma illness representations or perception, were published after 2000, and available in English. Fifteen articles were selected for inclusion. All of the articles are descriptive studies that used cross-sectional designs. Seven of the studies used parent and child participants, eight used parents only, and none used only child participants. None of the selected studies describe child asthma illness representations, and only three describe parental asthma illness representations. Domains of illness representations, including symptoms, timeline, consequences, cause, and controllability were described in the remaining articles. Symptoms and controllability appear to have the most influence on parental asthma management practices. Parents prefer symptomatic or intermittent asthma management and frequently cite concerns regarding daily controller medication use. Parents also primarily rely on their own objective symptom observations rather than the child's report of symptoms. Asthma illness representations are an important area of future study to better understand parent-child shared asthma management.

  13. From the Osterwalder canvas to an alternative business model representation

    OpenAIRE

    Verrue, Johan

    2015-01-01

    The Osterwalder business model canvas (BMC) is used by many entrepreneurs, managers, consultants and business schools. In our research we have investigated whether the canvas is a valid instrument for gaining an in-depth, accurate insight into business models. Therefore we have performed initial multiple case study research which concluded that the canvas does not generate valid business model (BM) representations. In our second multiple case study, we have constructed an alternative BM frame...

  14. Hyperfinite representation of distributions

    Indian Academy of Sciences (India)

    in the description in [4] of an elementary ultrapower model of the hyperreals. For a more detailed study of the ... 4 ┴ ├Z. Defining addition and scalar multiplication componentwise, ΠF is a ├C-linear space of hyperfinite ..... ΠG is a Π-difference algebra which contains ΠD as a linear submodule and ΠGI as a subalgebra.

  15. A structured representation for parallel algorithm design on multicomputers

    International Nuclear Information System (INIS)

    Sun, Xian-He; Ni, L.M.

    1991-01-01

    Traditionally, parallel algorithms have been designed by brute force methods and fine-tuned on each architecture to achieve high performance. Rather than studying the design case by case, a systematic approach is proposed. A notation is first developed. Using this notation, most of the frequently used scientific and engineering applications can be presented by simple formulas. The formulas constitute the structured representation of the corresponding applications. The structured representation is simple, adequate and easy to understand. They also contain sufficient information about uneven allocation and communication latency degradations. With the structured representation, applications can be compared, classified and partitioned. Some of the basic building blocks, called computation models, of frequently used applications are identified and studied. Most applications are combinations of some computation models. The structured representation relates general applications to computation models. Studying computation models leads to a guideline for efficient parallel algorithm design for general applications. 6 refs., 7 figs

  16. Impact of mental representational systems on design interface.

    Energy Technology Data Exchange (ETDEWEB)

    Brown-VanHoozer, S. A.

    1998-02-25

    The purpose of the studies conducted at Argonne National Laboratory is to understand the impact mental representational systems have in identifying how user comfort parameters influence how information is to best be presented. By understanding how each individual perceives information based on the three representational systems (visual, auditory and kinesthetic modalities), it has been found that a different approach must be taken in the design of interfaces resulting in an outcome that is much more effective and representative of the users mental model. This paper will present current findings and future theories to be explored.

  17. Computer aided surface representation

    Energy Technology Data Exchange (ETDEWEB)

    Barnhill, R.E.

    1989-02-09

    The central research problem of this project is the effective representation and display of surfaces, interpolating to given information, in three or more dimensions. In a typical problem, we wish to create a surface from some discrete information. If this information is itself on another surface, the problem is to determine a surface defined on a surface,'' which is discussed below. Often, properties of an already constructed surface are desired: such geometry processing'' is described below. The Summary of Proposed Research from our original proposal describes the aims of this research project. This Summary and the Table of Contents from the original proposal are enclosed as an Appendix to this Progress Report. The broad sweep from constructive mathematics through algorithms and computer graphics displays is utilized in the research. The wide range of activity, directed in both theory and applications, makes this project unique. Last month in the first Ardent Titan delivered in the State of Arizona came to our group, funded by the DOE and Arizona State University. Although the Titan is a commercial product, its newness requires our close collaboration with Ardent to maximize results. During the past year, four faculty members and several graduate research assistants have worked on this DOE project. The gaining of new professionals is an important aspect of this project. A listing of the students and their topics is given in the Appendix. The most significant publication during the past year is the book, Curves and Surfaces for Computer Aided Geometric Design, by Dr. Gerald Farin. This 300 page volume helps fill a considerable gap in the subject and includes many new results on Bernstein-Bezier curves and surfaces.

  18. Progress in visual representations of chemical space.

    Science.gov (United States)

    Osolodkin, Dmitry I; Radchenko, Eugene V; Orlov, Alexey A; Voronkov, Andrey E; Palyulin, Vladimir A; Zefirov, Nikolay S

    2015-01-01

    The concept of 'chemical space' reveals itself in two forms: the discrete set of all possible molecules, and multi-dimensional descriptor space encompassing all the possible molecules. Approaches based on this concept are widely used for the analysis and enumeration of compound databases, library design, and structure-activity relationships (SAR) and landscape studies. Visual representations of chemical space differ in their applicability domains and features and require expert knowledge for choosing the right tool for a particular problem. In this review, the authors present recent advances in visualization of the chemical space in the framework of current general understanding of this topic. Attention is given to such methods as van Krevelen diagrams, descriptor plots, principal components analysis (PCA), self-organizing maps (SOM), generative topographic mapping (GTM), graph and network-based approaches. Notable application examples are provided. With the growth of computational power, representations of large datasets are becoming more and more common instruments in the toolboxes of chemoinformaticians. Every scientist in the field can find the method of choice for a particular task. However, there is no universal reference representation of the chemical space currently available and expert knowledge is required.

  19. Discursive Representations of Asylum Seekers and Illegal Immigrants in Ireland

    Directory of Open Access Journals (Sweden)

    Elaine Burroughs

    2013-12-01

    Full Text Available Migrants are often referred to as an all encompassing group of people and the “many faces of migration”, the variety of people, legalities and complexities involved, can be overlooked. The same can be said for non-EU migrants in the Irish context. Non-EU migrants (or those that are not Caucasian are generally viewed to be a distinct cohort of comparable migrants. Indeed, these migrants are often portrayed in a broadly negative way by key Irish institutions (such as the parliament or the media, and these representations impact upon how Irish society views non-EU migration and indeed migration in general. While Ireland is by no means the only European country in which this type of practice occurs, this paper aims to draw attention to generalized, inaccurate and misleading representations of non-EU migrants in Ireland, by specifically examining representations of asylum seekers and illegal immigrants. There can be an overlap in how these “types” of migrants are conceptualized and this paper therefore aims to develop an understanding of the implications involved for migrants categorized as an “asylum seeker” or an “illegal immigrant.” Furthermore, these topics are under-researched within the Irish context, yet they receive much political and public attention. At the same time however, this paper aims to challenge the labels assigned to non-EU migrants and the terminology that is used to define their identity so concretely. In the Irish context there is much confusion in relation to the multiple “faces” of non-EU migration, as a range of terminology is used to refer to them. This terminology is often used in an interchangeable manner, in an array of societal contexts. There is a consistent (whether this happens intentionally or unintentionally is debatable misuse of categories and migration terminology in Irish institutional discourses. Quite often those seeking asylum are referred to as illegal immigrants and vice versa

  20. Generalized movement representation in haptic perception.

    Science.gov (United States)

    Dupin, Lucile; Hayward, Vincent; Wexler, Mark

    2017-03-01

    The extraction of spatial information by touch often involves exploratory movements, with tactile and kinesthetic signals combined to construct a spatial haptic percept. However, the body has many tactile sensory surfaces that can move independently, giving rise to the source binding problem: when there are multiple tactile signals originating from sensory surfaces with multiple movements, are the tactile and kinesthetic signals bound to one another? We studied haptic signal combination by applying the tactile signal to a stationary fingertip while another body part (the other hand or a foot) or a visual target moves, and using a task that can only be done if the tactile and kinesthetic signals are combined. We found that both direction and speed of movement transfer across limbs, but only direction transfers between visual target motion and the tactile signal. In control experiments, we excluded the role of explicit reasoning or knowledge of motion kinematics in this transfer. These results demonstrate the existence of 2 motion representations in the haptic system-one of direction and another of speed or amplitude-that are both source-free or unbound from their sensory surface of origin. These representations may well underlie our flexibility in haptic perception and sensorimotor control. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  1. Representations as Mediation between Purposes as Junior Secondary Science Students Learn about the Human Body

    Science.gov (United States)

    Olander, Clas; Wickman, Per-Olof; Tytler, Russell; Ingerman, Åke

    2018-01-01

    The aim of this article is to investigate students' meaning-making processes of multiple representations during a teaching sequence about the human body in lower secondary school. Two main influences are brought together to accomplish the analysis: on the one hand, theories on signs and representations as scaffoldings for learning and, on the…

  2. Multiple Pregnancy

    Science.gov (United States)

    ... Education & Events Advocacy For Patients About ACOG Multiple Pregnancy Home For Patients Search FAQs Multiple Pregnancy Page ... Multiple Pregnancy FAQ188, July 2015 PDF Format Multiple Pregnancy Pregnancy How does multiple pregnancy occur? What are ...

  3. Visual Ethnography, Thick Description and Cultural Representation

    Directory of Open Access Journals (Sweden)

    Dipesh Kharel

    2015-12-01

    Full Text Available The purposes of this paper are threefold: to cover historical, theoretical and methodological overview of visual ethnography (photography and film as a research tool in studying culture; to examine visual ethnography as a means of cultural representation, and to discuss visual ethnographic method with Clifford Geertz’s idea of “thick description”. I hope to bring some clarity and consensus to our understanding how visual ethnography can be an adequate research tool for “thick description” and a study of culture. Furthermore, in this paper, I begin by seeing visual ethnography in the context to visual anthropology, photography, ethnographic film, and semiotics.

  4. A 'more-than-representational' mapping study

    DEFF Research Database (Denmark)

    Lanng, Ditte Bendix

    2018-01-01

    In urban design mapping is a generative tool that can evoke site conditions and animate design potentials. James Corner has stated that a “map is already a project in the making” (1999b, p.216), and thereby points to the evocative ‘agency’ of mapping in composing a design project. This paper takes...... Corner’s essay as its starting point. It couples his considerations with non-representational research to elaborate mapping as a ‘more-than-representational’ tool with which to think and work when we seek to understand and evoke design sites in conjunction with the lived world. This coupling is done...

  5. Collective form generation through visual participatory representation

    DEFF Research Database (Denmark)

    Day, Dennis; Sharma, Nishant; Punekar, Ravi

    2012-01-01

    In order to inspire and inform designers with the users data from participatory research, it may be important to represent data in a visual format that is easily understandable to the designers. For a case study in vehicle design, the paper outlines visual representation of data and the use...... of the same in the collective form generation session with a set of designers (vehicle design students) where designers use sketching as a tool to discuss, conceptualise and negotiate concepts towards the final vehicle form. Further, this paper attempts to demonstrate how deep and tacit context sensitive...

  6. Multiple sclerosis; Multiple Sklerose

    Energy Technology Data Exchange (ETDEWEB)

    Grunwald, I.Q.; Kuehn, A.L.; Backens, M.; Papanagiotou, P. [Universitaet des Saarlandes, Abteilung fuer Diagnostische und Interventionelle Neuroradiologie, Radiologische Klinik, Homburg/Saar (Germany); Shariat, K. [Universitaet des Saarlandes, Klinik fuer Neurochirurgie, Homburg/Saar (Germany); Kostopoulos, P. [Universitaet des Saarlandes, Klinik fuer Neurologie, Homburg/Saar (Germany)

    2008-06-15

    Multiple sclerosis is the most common chronic inflammatory disease of myelin with interspersed lesions in the white matter of the central nervous system. Magnetic resonance imaging (MRI) plays a key role in the diagnosis and monitoring of white matter diseases. This article focuses on key findings in multiple sclerosis as detected by MRI. (orig.) [German] Die Multiple Sklerose (MS) ist die haeufigste chronisch-entzuendliche Erkrankung des Myelins mit eingesprengten Laesionen im Bereich der weissen Substanz des zentralen Nervensystems. Die Magnetresonanztomographie (MRT) hat bei der Diagnosestellung und Verlaufskontrolle eine Schluesselrolle. Dieser Artikel befasst sich mit Hauptcharakteristika der MR-Bildbebung. (orig.)

  7. Building scientific literacy/(ies): A cross-case analysis of how multimodal representations are used to make meaning during scientific inquiry

    Science.gov (United States)

    Shannon, Christa L.

    This study used a Social Semiotic framework to describe the nature of multimodal textual representations created by fourth grade students in a small rural Texas school district south of Dallas in order to answer the question: What is the nature of the multimodal textual representations created by fourth grade students during the scientific inquiry process? Results of the cross case-analysis of the students' digitally recorded reflections, their multimodal representations, and my field notes and personal reflections as a teacher-researcher were indicative of five major themes. Representations created by the students: (a) were supported by scientific learning communities; (b) demonstrated varying abilities to collect both qualitative and quantitative observations; (c) utilized a variety of graphic organizers to communicate/represent scientific information; (d) were influenced by previous instruction and experience; and (e) showed development over time. These findings suggested the need for changes in the learning environment and pedagogy of science as teachers provide environments that support the development of learning communities; provide multiple opportunities for students to make both qualitative and quantitative observations during scientific inquiry; provide explicit instruction into the semiotic tools used by professional scientists to communicate/represent meaning; and allow students the opportunity to reflect, critique, and discuss their representations so that they can learn to be more competent and fluent representors of scientific knowledge. Recommendations for future research included: learning more about the way learning communities scaffold the learning process during scientific inquiry; understanding the best practices for helping students to learn how to make qualitative and quantitative observations of the world around them; describing the best practices for teaching students to be multimodal designers of scientific knowledge;examining the effect

  8. How lateral connections and spiking dynamics may separate multiple objects moving together.

    Directory of Open Access Journals (Sweden)

    Benjamin D Evans

    Full Text Available Over successive stages, the ventral visual system of the primate brain develops neurons that respond selectively to particular objects or faces with translation, size and view invariance. The powerful neural representations found in Inferotemporal cortex form a remarkably rapid and robust basis for object recognition which belies the difficulties faced by the system when learning in natural visual environments. A central issue in understanding the process of biological object recognition is how these neurons learn to form separate representations of objects from complex visual scenes composed of multiple objects. We show how a one-layer competitive network comprised of 'spiking' neurons is able to learn separate transformation-invariant representations (exemplified by one-dimensional translations of visual objects that are always seen together moving in lock-step, but separated in space. This is achieved by combining 'Mexican hat' functional lateral connectivity with cell firing-rate adaptation to temporally segment input representations of competing stimuli through anti-phase oscillations (perceptual cycles. These spiking dynamics are quickly and reliably generated, enabling selective modification of the feed-forward connections to neurons in the next layer through Spike-Time-Dependent Plasticity (STDP, resulting in separate translation-invariant representations of each stimulus. Variations in key properties of the model are investigated with respect to the network's ability to develop appropriate input representations and subsequently output representations through STDP. Contrary to earlier rate-coded models of this learning process, this work shows how spiking neural networks may learn about more than one stimulus together without suffering from the 'superposition catastrophe'. We take these results to suggest that spiking dynamics are key to understanding biological visual object recognition.

  9. Homogeneous Operators and Projective Representations

    Indian Academy of Sciences (India)

    Abstract. This paper surveys the existing literature on homogeneous operators and their relationships with projective representations of P S L ( 2 , R ) and other Lie groups. It also includes a list of open problems in this area.

  10. Number theory via Representation theory

    Indian Academy of Sciences (India)

    2014-11-09

    Number theory via Representation theory. Eknath Ghate. November 9, 2014. Eightieth Annual Meeting, Chennai. Indian Academy of Sciences1. 1. This is a non-technical 20 minute talk intended for a general Academy audience.

  11. Computer representation of molecular surfaces

    International Nuclear Information System (INIS)

    Max, N.L.

    1981-01-01

    This review article surveys recent work on computer representation of molecular surfaces. Several different algorithms are discussed for producing vector or raster drawings of space-filling models formed as the union of spheres. Other smoother surfaces are also considered

  12. (Self)-representations on youtube

    DEFF Research Database (Denmark)

    Simonsen, Thomas Mosebo

    This paper examines forms of self-representation on YouTube with specific focus on Vlogs (Video blogs). The analytical scope of the paper is on how User-generated Content on YouTube initiates a certain kind of audiovisual representation and a particular interpretation of reality that can...... be distinguished within Vlogs. This will be analysed through selected case studies taken from a representative sample of empirically based observations of YouTube videos. The analysis includes a focus on how certain forms of representation can be identified as representations of the self (Turkle 1995, Scannell...... 1996, Walker 2005) and further how these forms must be comprehended within a context of technological constrains, institutional structures and social as well as economical practices on YouTube (Burgess and Green 2009, Van Dijck 2009). It is argued that these different contexts play a vital part...

  13. Vietnamese Document Representation and Classification

    Science.gov (United States)

    Nguyen, Giang-Son; Gao, Xiaoying; Andreae, Peter

    Vietnamese is very different from English and little research has been done on Vietnamese document classification, or indeed, on any kind of Vietnamese language processing, and only a few small corpora are available for research. We created a large Vietnamese text corpus with about 18000 documents, and manually classified them based on different criteria such as topics and styles, giving several classification tasks of different difficulty levels. This paper introduces a new syllable-based document representation at the morphological level of the language for efficient classification. We tested the representation on our corpus with different classification tasks using six classification algorithms and two feature selection techniques. Our experiments show that the new representation is effective for Vietnamese categorization, and suggest that best performance can be achieved using syllable-pair document representation, an SVM with a polynomial kernel as the learning algorithm, and using Information gain and an external dictionary for feature selection.

  14. Semantic Knowledge Representation (SKR) API

    Data.gov (United States)

    U.S. Department of Health & Human Services — The SKR Project was initiated at NLM in order to develop programs to provide usable semantic representation of biomedical free text by building on resources...

  15. Representability of Hom implies flatness

    Indian Academy of Sciences (India)

    ... A basic result of Grothendieck ([EGA], III 7.7.9) says that if F is flat over then hom ( E , F ) is representable for all E . We prove the converse of the above, in fact, we show that if is a relatively ample line bundle on over such that the functor hom ( L − n , F ) is representable for infinitely many positive integers , then F ...

  16. The Fifth Mode of Representation

    DEFF Research Database (Denmark)

    Hansen, Per Krogh; Behrendt, Poul Olaf

    2011-01-01

    “The fifth mode of representation: Ambiguous voices in unreliable third person narration”. Sammen med Poul Behrendt. In Per Krogh Hansen, Stefan Iversen, Henrik Skov Nielsen og Rolf Reitan (red.): Strange Voices. Walter de Gruyter, Berlin & New York......“The fifth mode of representation: Ambiguous voices in unreliable third person narration”. Sammen med Poul Behrendt. In Per Krogh Hansen, Stefan Iversen, Henrik Skov Nielsen og Rolf Reitan (red.): Strange Voices. Walter de Gruyter, Berlin & New York...

  17. Representation theory for strange attractors.

    Science.gov (United States)

    Cross, Daniel J; Gilmore, R

    2009-11-01

    Embeddings are diffeomorphisms between some unseen physical attractor and a reconstructed image. Different embeddings may or may not be equivalent under isotopy. We regard embeddings as representations of the attractor, review the labels required to distinguish inequivalent representations for an important class of dynamical systems, and discuss the systematic ways inequivalent embeddings become equivalent as the embedding dimension increases until there is finally only one "universal" embedding in a suitable dimension.

  18. Functional representations of integrable hierarchies

    International Nuclear Information System (INIS)

    Dimakis, Aristophanes; Mueller-Hoissen, Folkert

    2006-01-01

    We consider a general framework for integrable hierarchies in Lax form and derive certain universal equations from which 'functional representations' of particular hierarchies (such as KP, discrete KP, mKP, AKNS), i.e. formulations in terms of functional equations, are systematically and quite easily obtained. The formalism genuinely applies to hierarchies where the dependent variables live in a noncommutative (typically matrix) algebra. The obtained functional representations can be understood as 'noncommutative' analogues of 'Fay identities' for the KP hierarchy

  19. Turning Symbolic: The representation of motion direction in working memory

    Directory of Open Access Journals (Sweden)

    Tal eSeidel Malkinson

    2016-02-01

    Full Text Available What happens to the representation of a moving stimulus when it is no longer present and its motion direction has to be maintained in working memory (WM? Is the initial, sensorial representation maintained during the delay period or is there another representation, at a higher level of abstraction? It is also feasible that multiple representations may co-exist in WM, manifesting different facets of sensory and more abstract features.To that end, we investigated the mnemonic representation of motion direction in a series of three psychophysical experiments, using a delayed motion-discrimination task (relative clockwisecounter-clockwise judgment. First, we show that a change in the dots' contrast polarity does not hamper performance. Next, we demonstrate that performance is unaffected by relocation of the Test stimulus in either retinotopic or spatiotopic coordinate frames. Finally, we show that an arrow-shaped cue presented during the delay interval between the Sample and Test stimulus, biases performance towards the direction of the arrow, although the cue itself is non-informative (it has no predictive value of the correct answer. These results indicate that the representation of motion direction in WM is independent of the physical features of the stimulus (polarity or position and has non-sensorial abstract qualities. It is plausible that an abstract mnemonic trace might be activated alongside a more basic, analogue representation of the stimulus. We speculate that the specific sensitivity of the mnemonic representation to the arrow-shaped symbol may stem from the long term learned association between direction and the hour in the clock.

  20. Turning Symbolic: The Representation of Motion Direction in Working Memory

    Science.gov (United States)

    Seidel Malkinson, Tal; Pertzov, Yoni; Zohary, Ehud

    2016-01-01

    What happens to the representation of a moving stimulus when it is no longer present and its motion direction has to be maintained in working memory (WM)? Is the initial, sensorial representation maintained during the delay period or is there another representation, at a higher level of abstraction? It is also feasible that multiple representations may co-exist in WM, manifesting different facets of sensory and more abstract features. To that end, we investigated the mnemonic representation of motion direction in a series of three psychophysical experiments, using a delayed motion-discrimination task (relative clockwise∖counter-clockwise judgment). First, we show that a change in the dots’ contrast polarity does not hamper performance. Next, we demonstrate that performance is unaffected by relocation of the Test stimulus in either retinotopic or spatiotopic coordinate frames. Finally, we show that an arrow-shaped cue presented during the delay interval between the Sample and Test stimulus, strongly biases performance toward the direction of the arrow, although the cue itself is non-informative (it has no predictive value of the correct answer). These results indicate that the representation of motion direction in WM could be independent of the physical features of the stimulus (polarity or position) and has non-sensorial abstract qualities. It is plausible that an abstract mnemonic trace might be activated alongside a more basic, analog representation of the stimulus. We speculate that the specific sensitivity of the mnemonic representation to the arrow-shaped symbol may stem from the long term learned association between direction and the hour in the clock. PMID:26909059

  1. Neural representations of the sense of self

    Science.gov (United States)

    Klemm, William R.

    2011-01-01

    The brain constructs representations of what is sensed and thought about in the form of nerve impulses that propagate in circuits and network assemblies (Circuit Impulse Patterns, CIPs). CIP representations of which humans are consciously aware occur in the context of a sense of self. Thus, research on mechanisms of consciousness might benefit from a focus on how a conscious sense of self is represented in brain. Like all senses, the sense of self must be contained in patterns of nerve impulses. Unlike the traditional senses that are registered by impulse flow in relatively simple, pauci-synaptic projection pathways, the sense of self is a system- level phenomenon that may be generated by impulse patterns in widely distributed complex and interacting circuits. The problem for researchers then is to identify the CIPs that are unique to conscious experience. Also likely to be of great relevance to constructing the representation of self are the coherence shifts in activity timing relations among the circuits. Consider that an embodied sense of self is generated and contained as unique combinatorial temporal patterns across multiple neurons in each circuit that contributes to constructing the sense of self. As with other kinds of CIPs, those representing the sense of self can be learned from experience, stored in memory, modified by subsequent experiences, and expressed in the form of decisions, choices, and commands. These CIPs are proposed here to be the actual physical basis for conscious thought and the sense of self. When active in wakefulness or dream states, the CIP representations of self act as an agent of the brain, metaphorically as an avatar. Because the selfhood CIP patterns may only have to represent the self and not directly represent the inner and outer worlds of embodied brain, the self representation should have more degrees of freedom than subconscious mind and may therefore have some capacity for a free-will mind of its own. S everal lines of

  2. Investigating the Representation of Multiple Intelligences Theory in TPSOL Textbooks

    Science.gov (United States)

    Ebadi, Saman; Beigzadeh, Maryam

    2016-01-01

    As the main applicable language resources in classrooms, textbooks provide the primary source of information, and they serve the foundation of instruction and transfer the curriculum objectives. Therefore, teachers should be conscious in choosing the right textbooks and activities for their students. The purpose of this study is to investigate one…

  3. Multiple representations of a human rights violation: Competing ...

    African Journals Online (AJOL)

    If reconciliation is viewed as "the formal attainment of the political and constitutional unity of the country", then the TRC is ... political and historical context of the TRC and of deeply entrenched attitudes and worldviews of the narrators, and may thus ...... the correctness of Benzien's responses. The final statement affirms his ...

  4. Multiple representations of a human rights violation: Competing ...

    African Journals Online (AJOL)

    emphasises the interdependence and obligations of mutual respect, value and acceptance of members of a ..... result the primary official sources of information for journalists were the daily police reports, as indicated ..... For others, among them Afrikaner poet and journalist Antjie Krog (1998), the hearing awakened complex.

  5. Multiple representations in web-based learning of chemistry concepts

    NARCIS (Netherlands)

    Vermaat, J.H.; Terlouw, C.; Dijkstra, S.

    2003-01-01

    A new chemistry curriculum for secondary schools is currently under construction in the Netherlands, in which chemical knowledge will be embedded in contexts that show applications of chemistry in the society. Several research groups develop such modules and a committee appointed by the Dutch

  6. A Multiple-Representation Paradigm for Document Development

    Science.gov (United States)

    1988-07-05

    include spelling checking, writing style verification, bibliographical citations , etc. It may also include graphics, table, mathem atics, or any other...references, and indexes. Bibliographical citations are references to a certain combination of bibliographical entries listed in a special section of a...inform the reader that related material can be found in the contexts those numbers desig- nate (usually certain pages). Like bibliographical citations , index

  7. Unfolding Fraction Multiplication

    Science.gov (United States)

    Wyberg, Terry; Whitney, Stephanie R.; Cramer, Kathleen A.; Monson, Debra S.; Leavitt, Seth

    2011-01-01

    Students often have difficulty understanding fractions, in general, and understanding how to multiply fractions, in particular. To move past this potential problem area, students need to develop a deeper understanding of multiplication and connect the ideas to fractions. In this article, the authors share their insights into teaching fraction…

  8. Chomsky-Schützenberger parsing for weighted multiple context-free languages

    Directory of Open Access Journals (Sweden)

    Tobias Denkinger

    2017-07-01

    Full Text Available We prove a Chomsky-Schützenberger representation theorem for multiple context-free languages weighted over complete commutative strong bimonoids. Using this representation we devise a parsing algorithm for a restricted form of those devices.

  9. Multiple sclerosis.

    Science.gov (United States)

    Thompson, Alan J; Baranzini, Sergio E; Geurts, Jeroen; Hemmer, Bernhard; Ciccarelli, Olga

    2018-03-22

    Multiple sclerosis continues to be a challenging and disabling condition but there is now greater understanding of the underlying genetic and environmental factors that drive the condition, including low vitamin D levels, cigarette smoking, and obesity. Early and accurate diagnosis is crucial and is supported by diagnostic criteria, incorporating imaging and spinal fluid abnormalities for those presenting with a clinically isolated syndrome. Importantly, there is an extensive therapeutic armamentarium, both oral and by infusion, for those with the relapsing remitting form of the disease. Careful consideration is required when choosing the correct treatment, balancing the side-effect profile with efficacy and escalating as clinically appropriate. This move towards more personalised medicine is supported by a clinical guideline published in 2018. Finally, a comprehensive management programme is strongly recommended for all patients with multiple sclerosis, enhancing health-related quality of life through advocating wellness, addressing aggravating factors, and managing comorbidities. The greatest remaining challenge for multiple sclerosis is the development of treatments incorporating neuroprotection and remyelination to treat and ultimately prevent the disabling, progressive forms of the condition. Copyright © 2018 Elsevier Ltd. All rights reserved.

  10. Illness representations in patients with traumatic injury: a longitudinal study.

    Science.gov (United States)

    Lee, Bih-O; Chaboyer, Wendy; Wallis, Marianne

    2010-02-01

    This study aimed to elucidate the illness representations of patients with traumatic injury and to examine what extent their illness representations change over time. Traumatic injury has attracted global concern because it is the major reason for death and disability in people under 45 years old. One model, the Common Sense Model of Illness Representation (CSMIR), has the potential to help individuals adjust to changes in health status such as traumatic injury. Longitudinal study design. This study was conducted using a and collected data prior to hospital discharge and at three and six months after hospital discharge. One individual question form and the Chinese Illness Perception Questionnaire Revised (IPQ-R) (Trauma) were used to collect demographic data, clinical data and illness representations. A total of 114 participants completed the survey three times. The overall response rate was 79.7%. Six subscales of the Chinese (Trauma): identity, emotional representations, consequences, controllability, illness coherence and causes of the Chinese IPQ-R (Trauma) changed significantly over time. Two subscales, Timeline (acute/chronic) and Timeline Cyclical, did not change significantly. Based on these findings, there may be a window of opportunity to provide appropriate interventions to individuals with traumatic injury at each time point. The results of this study have implications for nursing practice and further nursing research. Understanding illness representation in patients with traumatic injury may help nurses to provide anticipatory guidance and to design nursing interventions before and after hospital discharge, ultimately to improve health outcomes of those patients.

  11. Bi-Level Semantic Representation Analysis for Multimedia Event Detection.

    Science.gov (United States)

    Chang, Xiaojun; Ma, Zhigang; Yang, Yi; Zeng, Zhiqiang; Hauptmann, Alexander G

    2017-05-01

    Multimedia event detection has been one of the major endeavors in video event analysis. A variety of approaches have been proposed recently to tackle this problem. Among others, using semantic representation has been accredited for its promising performance and desirable ability for human-understandable reasoning. To generate semantic representation, we usually utilize several external image/video archives and apply the concept detectors trained on them to the event videos. Due to the intrinsic difference of these archives, the resulted representation is presumable to have different predicting capabilities for a certain event. Notwithstanding, not much work is available for assessing the efficacy of semantic representation from the source-level. On the other hand, it is plausible to perceive that some concepts are noisy for detecting a specific event. Motivated by these two shortcomings, we propose a bi-level semantic representation analyzing method. Regarding source-level, our method learns weights of semantic representation attained from different multimedia archives. Meanwhile, it restrains the negative influence of noisy or irrelevant concepts in the overall concept-level. In addition, we particularly focus on efficient multimedia event detection with few positive examples, which is highly appreciated in the real-world scenario. We perform extensive experiments on the challenging TRECVID MED 2013 and 2014 datasets with encouraging results that validate the efficacy of our proposed approach.

  12. Evolved Representation and Computational Creativity

    Directory of Open Access Journals (Sweden)

    Ashraf Fouad Hafez Ismail

    2001-01-01

    Full Text Available Advances in science and technology have influenced designing activity in architecture throughout its history. Observing the fundamental changes to architectural designing due to the substantial influences of the advent of the computing era, we now witness our design environment gradually changing from conventional pencil and paper to digital multi-media. Although designing is considered to be a unique human activity, there has always been a great dependency on design aid tools. One of the greatest aids to architectural design, amongst the many conventional and widely accepted computational tools, is the computer-aided object modeling and rendering tool, commonly known as a CAD package. But even though conventional modeling tools have provided designers with fast and precise object handling capabilities that were not available in the pencil-and-paper age, they normally show weaknesses and limitations in covering the whole design process.In any kind of design activity, the design worked on has to be represented in some way. For a human designer, designs are for example represented using models, drawings, or verbal descriptions. If a computer is used for design work, designs are usually represented by groups of pixels (paintbrush programs, lines and shapes (general-purpose CAD programs or higher-level objects like ‘walls’ and ‘rooms’ (purpose-specific CAD programs.A human designer usually has a large number of representations available, and can use the representation most suitable for what he or she is working on. Humans can also introduce new representations and thereby represent objects that are not part of the world they experience with their sensory organs, for example vector representations of four and five dimensional objects. In design computing on the other hand, the representation or representations used have to be explicitly defined. Many different representations have been suggested, often optimized for specific design domains

  13. On Behavioral Equivalence of Rational Representations

    NARCIS (Netherlands)

    Trentelman, Harry L.; Willems, JC; Hara, S; Ohta, Y; Fujioka, H

    2010-01-01

    This article deals with the equivalence of representations of behaviors of linear differential systems In general. the behavior of a given linear differential system has many different representations. In this paper we restrict ourselves to kernel representations and image representations Two kernel

  14. 32 CFR 724.215 - Military representation.

    Science.gov (United States)

    2010-07-01

    ... 32 National Defense 5 2010-07-01 2010-07-01 false Military representation. 724.215 Section 724.215... BOARD Authority/Policy for Departmental Discharge Review § 724.215 Military representation. Military... consult legal counsel before undertaking such representation. Such representation may be prohibited by 18...

  15. Aboriginal Representation: Conflict or Dialogue in the Academy

    Science.gov (United States)

    Leane, Jeanine

    2010-01-01

    This research begins with the premise that non-Aboriginal students are challenged by much Aboriginal writing and also challenge its representations as they struggle to re-position themselves in relation to possible meanings within Aboriginal writing. Many non-Aboriginal students come to read an Aboriginal narrative against their understanding of…

  16. Baccalaureate Accounting Student Mentors' Social Representations of Their Mentorship Experiences

    Science.gov (United States)

    Roy, Vicky; Brown, Patricia A.

    2016-01-01

    Mentorship has been shown to enhance engagement, participation, and understanding of the workplace through the development of soft-skills and leadership capacity. This research identifies and describes the social representations of second and third year Baccalaureate accounting students relating to their experiences in mentoring first year…

  17. A Rationale for Hispanic Representation in Instructional Materials.

    Science.gov (United States)

    Carrasquillo, Angela L.

    1994-01-01

    Discusses the need for increased and more appropriate Hispanic representation in instructional materials at school to promote understanding of Latin culture. Stereotypes about Hispanics relate to punctuality, machismo, initiative, self-image, skin color, socioeconomic status, intelligence, parents' role in education, language proficiency, and…

  18. Integrating Particulate Representations into AP Chemistry and Introductory Chemistry Courses

    Science.gov (United States)

    Prilliman, Stephen G.

    2014-01-01

    The College Board's recently revised curriculum for advanced placement (AP) chemistry places a strong emphasis on conceptual understanding, including representations of particle phenomena. This change in emphasis is informed by years of research showing that students could perform algorithmic calculations but not explain those calculations…

  19. Social Representations as Mediators of Mathematics Learning in Multiethnic Classrooms

    Science.gov (United States)

    Gorgorio, Nuria; Planas, Nuria

    2005-01-01

    Drawing on socio-cultural theory, we understand the norms regulating the practices within the mathematics classroom as resulting from the social representations of the socially dominant groups and of the school culture related to what constitutes learning mathematics. Immigrant students, having their own personal histories as members of particular…

  20. Diagrammatic representation and reasoning

    CERN Document Server

    Meyer, Bernd; Olivier, Patrick

    2002-01-01

    Diagrams are essential in most fields of human activity. There is substan­ tial interest in diagrams and their use in many academic disciplines for the potential benefits they may confer on a wide range of tasks. Are we now in a position to claim that we have a science of diagrams-that is, a science which takes the nature of diagrams and their use as the central phenom­ ena of interest? If we have a science of diagrams it is certainly constituted from multiple disciplines, including cognitive science, psychology, artificial intelligence, logic, mathematics, and others. If there is a science of diagrams, then like other sciences there is an appli­ cations, or engineering, discipline that exists alongside the science. Applica­ tions and engineering provide tests of the theories and principles discovered by the science and extend the scope of the phenomena to be studied by gen­ erating new uses of diagrams, new media for presenting diagrams, or novel classes of diagram. This applications and engineering sid...

  1. Understanding Carbohydrates

    Science.gov (United States)

    ... Size: A A A Listen En Español Understanding Carbohydrates How much and what type of carbohydrate foods ... glucose levels in your target range. Explore: Understanding Carbohydrates Glycemic Index and Diabetes Learn about the glycemic ...

  2. Musings on multiplication tables and associated mathematics and teaching practices

    Directory of Open Access Journals (Sweden)

    Faaiz Gierdien

    2009-09-01

    Full Text Available This paper is based on my reflections on a deceptively simple tabular representation of a combined 12×12 multiplication table showing multiplier and multiplicand,starting at a time when I taught mathematics full time at a primary (elementary school through to my presentteaching of mathematics education modules to prospective teachers. A historically–motivated framework on the importance of tables as expressions of complex information in two–dimensional form is used to gain insight into and understand multiplication tables. Through this framework it is shown that the modal practice of “knowing one’s tables” in the primary grade levels is really about knowing sequenced and separated lists of whole number multiplications. In contrast, tabular multiplication sequences in a combined multiplication table can, through appropriate teaching practices, enable the discovery of multiple relationships beyond multiplication or arithmetic, resulting in significant mathematics that spans the grade levels. Implications for mathematics teacher education practice with its current focus mathematical knowledge for teaching, are considered.

  3. On Representation in Information Theory

    Directory of Open Access Journals (Sweden)

    Joseph E. Brenner

    2011-09-01

    Full Text Available Semiotics is widely applied in theories of information. Following the original triadic characterization of reality by Peirce, the linguistic processes involved in information—production, transmission, reception, and understanding—would all appear to be interpretable in terms of signs and their relations to their objects. Perhaps the most important of these relations is that of the representation-one, entity, standing for or representing some other. For example, an index—one of the three major kinds of signs—is said to represent something by being directly related to its object. My position, however, is that the concept of symbolic representations having such roles in information, as intermediaries, is fraught with the same difficulties as in representational theories of mind. I have proposed an extension of logic to complex real phenomena, including mind and information (Logic in Reality; LIR, most recently at the 4th International Conference on the Foundations of Information Science (Beijing, August, 2010. LIR provides explanations for the evolution of complex processes, including information, that do not require any entities other than the processes themselves. In this paper, I discuss the limitations of the standard relation of representation. I argue that more realistic pictures of informational systems can be provided by reference to information as an energetic process, following the categorial ontology of LIR. This approach enables naïve, anti-realist conceptions of anti-representationalism to be avoided, and enables an approach to both information and meaning in the same novel logical framework.

  4. Compact representations for the design of quantum logic

    CERN Document Server

    Niemann, Philipp

    2017-01-01

    This book discusses modern approaches and challenges of computer-aided design (CAD) of quantum circuits with a view to providing compact representations of quantum functionality. Focusing on the issue of quantum functionality, it presents Quantum Multiple-Valued Decision Diagrams (QMDDs – a means of compactly and efficiently representing and manipulating quantum logic. For future quantum computers, going well beyond the size of present-day prototypes, the manual design of quantum circuits that realize a given (quantum) functionality on these devices is no longer an option. In order to keep up with the technological advances, methods need to be provided which, similar to the design and synthesis of conventional circuits, automatically generate a circuit description of the desired functionality. To this end, an efficient representation of the desired quantum functionality is of the essence. While straightforward representations are restricted due to their (exponentially) large matrix descriptions and other de...

  5. Social Representations as Mediators of Practice in Mathematics Classrooms with Immigrant Students

    Science.gov (United States)

    Gorgorio, Nuria; de Abreu, Guida

    2009-01-01

    This article suggests that a critical perspective of the notion of social representations can offer useful insights into understanding practices of teaching and learning in mathematics classrooms with immigrant students. Drawing on literature using social representations, previous empirical studies are revisited to examine three specific…

  6. An introduction to quiver representations

    CERN Document Server

    Derksen, Harm

    2017-01-01

    This book is an introduction to the representation theory of quivers and finite dimensional algebras. It gives a thorough and modern treatment of the algebraic approach based on Auslander-Reiten theory as well as the approach based on geometric invariant theory. The material in the opening chapters is developed starting slowly with topics such as homological algebra, Morita equivalence, and Gabriel's theorem. Next, the book presents Auslander-Reiten theory, including almost split sequences and the Auslander-Reiten transform, and gives a proof of Kac's generalization of Gabriel's theorem. Once this basic material is established, the book goes on with developing the geometric invariant theory of quiver representations. The book features the exposition of the saturation theorem for semi-invariants of quiver representations and its application to Littlewood-Richardson coefficients. In the final chapters, the book exposes tilting modules, exceptional sequences and a connection to cluster categories. The book is su...

  7. Preon representations and composite models

    International Nuclear Information System (INIS)

    Kang, Kyungsik

    1982-01-01

    This is a brief report on the preon models which are investigated by In-Gyu Koh, A. N. Schellekens and myself and based on complex, anomaly-free and asymptotically free representations of SU(3) to SU(8), SO(4N+2) and E 6 with no more than two different preons. Complete list of the representations that are complex anomaly-free and asymptotically free has been given by E. Eichten, I.-G. Koh and myself. The assumptions made about the ground state composites and the role of Fermi statistics to determine the metaflavor wave functions are discussed in some detail. We explain the method of decompositions of tensor products with definite permutation properties which has been developed for this purpose by I.-G. Koh, A.N. Schellekens and myself. An example based on an anomaly-free representation of the confining metacolor group SU(5) is discussed

  8. Vivid Representations and Their Effects

    Directory of Open Access Journals (Sweden)

    Kengo Miyazono

    2018-04-01

    Full Text Available Sinhababu’s Humean Nature contains many interesting and important ideas, but in this short commentary I focus on the idea of vivid representations. Sinhababu inherits his idea of vivid representations from Hume’s discussions, in particular his discussion of calm and violent passions. I am sympathetic to the idea of developing Hume’s insight that has been largely neglected by philosophers. I believe that Sinhababu and Hume are on the right track. What I do in this short commentary is to raise some questions about the details. The aim of asking these questions is not to challenge Sinhababu’s proposal (at least his main ideas, but rather to point at some interesting issues arising out of his proposal. The questions are about (1 the nature of vividness, (2 the effects of vivid representations, and (3 Sinhababu’s account of alief cases.

  9. Executive control influences linguistic representations.

    Science.gov (United States)

    Lev-Ari, Shiri; Keysar, Boaz

    2014-02-01

    Although it is known that words acquire their meanings partly from the contexts in which they are used, we proposed that the way in which words are processed can also influence their representation. We further propose that individual differences in the way that words are processed can consequently lead to individual differences in the way that they are represented. Specifically, we showed that executive control influences linguistic representations by influencing the coactivation of competing and reinforcing terms. Consequently, people with poorer executive control perceive the meanings of homonymous terms as being more similar to one another, and those of polysemous terms as being less similar to one another, than do people with better executive control. We also showed that bilinguals with poorer executive control experience greater cross-linguistic interference than do bilinguals with better executive control. These results have implications for theories of linguistic representation and language organization.

  10. Digital models for architectonical representation

    Directory of Open Access Journals (Sweden)

    Stefano Brusaporci

    2011-12-01

    Full Text Available Digital instruments and technologies enrich architectonical representation and communication opportunities. Computer graphics is organized according the two phases of visualization and construction, that is modeling and rendering, structuring dichotomy of software technologies. Visualization modalities give different kinds of representations of the same 3D model and instruments produce a separation between drawing and image’s creation. Reverse modeling can be related to a synthesis process, ‘direct modeling’ follows an analytic procedure. The difference between interactive and not interactive applications is connected to the possibilities offered by informatics instruments, and relates to modeling and rendering. At the same time the word ‘model’ describes different phenomenon (i.e. files: mathematical model of the building and of the scene; raster representation and post-processing model. All these correlated different models constitute the architectonical interpretative model, that is a simulation of reality made by the model for improving the knowledge.

  11. Task Specific versus Generalized Mnemonic Representations in Parietal and Prefrontal Cortices

    Science.gov (United States)

    Sarma, Arup; Masse, Nicolas Y.; Wang, Xiao-Jing; Freedman, David J.

    2016-01-01

    Our ability to learn a wide range of behavioral tasks is essential for responding appropriately to sensory stimuli according to behavioral demands, but the underlying neural mechanism has been rarely examined by neurophysiological recordings in the same subjects across learning. To understand how learning new behavioral tasks impacts underlying neuronal representations, we recorded from posterior parietal cortex (PPC) before and after training on a visual motion categorization task. Here we show that categorization training influenced cognitive encoding in PPC, with a marked enhancement of memory-related delay-period encoding during the categorization task which was absent during a motion discrimination task prior to categorization training. In contrast, the prefrontal cortex (PFC) exhibited strong delay-period encoding during both discrimination and categorization tasks. This reveals a dissociation between PFC’s and PPC’s roles in working memory, with general engagement of PFC across multiple tasks, in contrast with more task-specific mnemonic encoding in PPC. PMID:26595652

  12. Task-specific versus generalized mnemonic representations in parietal and prefrontal cortices.

    Science.gov (United States)

    Sarma, Arup; Masse, Nicolas Y; Wang, Xiao-Jing; Freedman, David J

    2016-01-01

    Our ability to learn a wide range of behavioral tasks is essential for responding appropriately to sensory stimuli according to behavioral demands, but the underlying neural mechanism has been rarely examined by neurophysiological recordings in the same subjects across learning. To understand how learning new behavioral tasks affects neuronal representations, we recorded from posterior parietal cortex (PPC) before and after training on a visual motion categorization task. We found that categorization training influenced cognitive encoding in PPC, with a marked enhancement of memory-related delay-period encoding during the categorization task that was absent during a motion discrimination task before categorization training. In contrast, the prefrontal cortex (PFC) exhibited strong delay-period encoding during both discrimination and categorization tasks. This reveals a dissociation between PFC's and PPC's roles in working memory, with general engagement of PFC across multiple tasks, in contrast with more task-specific mnemonic encoding in PPC.

  13. Concepts, ontologies, and knowledge representation

    CERN Document Server

    Jakus, Grega; Omerovic, Sanida; Tomažic, Sašo

    2013-01-01

    Recording knowledge in a common framework that would make it possible to seamlessly share global knowledge remains an important challenge for researchers. This brief examines several ideas about the representation of knowledge addressing this challenge. A widespread general agreement is followed that states uniform knowledge representation should be achievable by using ontologies populated with concepts. A separate chapter is dedicated to each of the three introduced topics, following a uniform outline: definition, organization, and use. This brief is intended for those who want to get to know

  14. Medieval theories of mental representation.

    Science.gov (United States)

    Kemp, S

    1998-11-01

    Throughout most of the Middle ages, it was generally held that stored mental representations of perceived objects or events preserved the forms or species of such objects. This belief was consistent with a metaphor used by Plato. It was also consistent with the medieval belief that a number of cognitive processes took place in the ventricles of the brain and with the phenomenology of afterimages and imagination itself. In the 14th century, William of Ockham challenged this belief by claiming that mental representations are not stored but instead constructed in the basis of past learned experiences.

  15. Congruence properties of induced representations

    DEFF Research Database (Denmark)

    Mayer, Dieter; Momeni, Arash; Venkov, Alexei

    In this paper we study representations of the projective modular group induced from the Hecke congruence group of level 4 with Selberg's character. We show that the well known congruence properties of Selberg's character are equivalent to the congruence properties of the induced representations. ...... by Zograf's geometric method. They belong to the class of character groups of type $\\rm I$ for the principal congruence subgroup $\\Gamma(4)$ and have, contrary to the noncongruence groups determined by Selberg's character which all have genus $g=0$, arbitrary genus $g\\geq 0$....

  16. Style representation in design grammars

    DEFF Research Database (Denmark)

    Ahmad, Sumbul; Chase, Scott Curland

    2012-01-01

    to be transformed according to changing design style needs. Issues of formalizing stylistic change necessitate a lucid and formal definition of style in the design language generated by a grammar. Furthermore, a significant aspect of the definition of style is the representation of aesthetic qualities attributed...... to the style. We focus on grammars for representing and generating styles of design and review the use of grammar transformations for modelling changes in style and design language. We identify a gap in knowledge in the representation of style in grammars and in driving strategic style change using grammar...

  17. Are baboons learning "orthographic" representations? Probably not.

    Directory of Open Access Journals (Sweden)

    Maja Linke

    Full Text Available The ability of Baboons (papio papio to distinguish between English words and nonwords has been modeled using a deep learning convolutional network model that simulates a ventral pathway in which lexical representations of different granularity develop. However, given that pigeons (columba livia, whose brain morphology is drastically different, can also be trained to distinguish between English words and nonwords, it appears that a less species-specific learning algorithm may be required to explain this behavior. Accordingly, we examined whether the learning model of Rescorla and Wagner, which has proved to be amazingly fruitful in understanding animal and human learning could account for these data. We show that a discrimination learning network using gradient orientation features as input units and word and nonword units as outputs succeeds in predicting baboon lexical decision behavior-including key lexical similarity effects and the ups and downs in accuracy as learning unfolds-with surprising precision. The models performance, in which words are not explicitly represented, is remarkable because it is usually assumed that lexicality decisions, including the decisions made by baboons and pigeons, are mediated by explicit lexical representations. By contrast, our results suggest that in learning to perform lexical decision tasks, baboons and pigeons do not construct a hierarchy of lexical units. Rather, they make optimal use of low-level information obtained through the massively parallel processing of gradient orientation features. Accordingly, we suggest that reading in humans first involves initially learning a high-level system building on letter representations acquired from explicit instruction in literacy, which is then integrated into a conventionalized oral communication system, and that like the latter, fluent reading involves the massively parallel processing of the low-level features encoding semantic contrasts.

  18. Supporting Fifth Graders in Learning Multiplication of Fraction with Whole Number

    Directory of Open Access Journals (Sweden)

    Cut Khairunnisa

    2012-07-01

    Full Text Available The meaning of fractions with integer multiplication is something thatis difficult to understand by students. They tend to think that theproduct it produces a larger number, while the multiplication offractions with integers, the result can be any number larger or smaller. This study is a research design that aims to develop a local instructional theory to support the students expand their understanding of the meaning of multiplication of fractions with integers. By applying the characteristics of realistic mathematics education (Realistic Mathematics Education, the researchers designed a series of instructional activities related to daily life, such as Indonesia prepares dishes and equitable distribution. Participants of this study were Grade 5 students from an elementary school in Surabaya, along with a mathematics teacher of that class. Some students of the class participated in the first cycle, in order to see how the design of the hypothetical learning trajectory (Hypothetical Learning Trajectory is running. After going through several revisions, HLT is then implemented in all the other students in grade 5. The results showed that students' prior knowledge affect their learning process. The fractions solve multiplication problems with whole numbers, some students convert the integers to fractions and then use a fraction by a fraction multiplication procedure. The learning process begins with students exploring the contextual situation of fair division, where students extend their understanding that the fraction associated with the division and multiplication. One indicator that the student has broadened his understanding is the more varied representation of the given problem.

  19. Modeling alpine grasslands with two integrated hydrologic models: a comparison of the different process representation in CATHY and GEOtop

    Science.gov (United States)

    Camporese, M.; Bertoldi, G.; Bortoli, E.; Wohlfahrt, G.

    2017-12-01

    Integrated hydrologic surface-subsurface models (IHSSMs) are increasingly used as prediction tools to solve simultaneously states and fluxes in and between multiple terrestrial compartments (e.g., snow cover, surface water, groundwater), in an attempt to tackle environmental problems in a holistic approach. Two such models, CATHY and GEOtop, are used in this study to investigate their capabilities to reproduce hydrological processes in alpine grasslands. The two models differ significantly in the complexity of the representation of the surface energy balance and the solution of Richards equation for water flow in the variably saturated subsurface. The main goal of this research is to show how these differences in process representation can lead to different predictions of hydrologic states and fluxes, in the simulation of an experimental site located in the Venosta Valley (South Tyrol, Italy). Here, a large set of relevant hydrological data (e.g., evapotranspiration, soil moisture) has been collected, with ground and remote sensing observations. The area of interest is part of a Long-Term Ecological Research (LTER) site, a mountain steep, heterogeneous slope, where the predominant land use types are meadow, pasture, and forest. The comparison between data and model predictions, as well as between simulations with the two IHSSMs, contributes to advance our understanding of the tradeoffs between different complexities in modeĺs process representation, model accuracy, and the ability to explain observed hydrological dynamics in alpine environments.

  20. Interparental conflict and children's school adjustment: the explanatory role of children's internal representations of interparental and parent-child relationships.

    Science.gov (United States)

    Sturge-Apple, Melissa L; Davies, Patrick T; Winter, Marcia A; Cummings, E Mark; Schermerhorn, Alice

    2008-11-01

    This study examined how children's insecure internal representations of interparental and parent-child relationships served as explanatory mechanisms in multiple pathways linking interparental conflict and parent emotional unavailability with the emotional and classroom engagement difficulties the children had in their adjustment to school. With their parents, 229 kindergarten children (127 girls and 102 boys, mean age = 6.0 years, SD = .50, at Wave 1) participated in this multimethod, 3-year longitudinal investigation. Findings revealed that children's insecure representations of the interparental relationship were a significant intervening mechanism in associations between observational ratings of interparental conflict and child and teacher reports on children's emotional and classroom difficulties in school over a 2-year period. Moreover, increased parental emotional unavailability accompanying high levels of interparental conflict was associated with children's insecure representations of the parent-child relationship and children's difficulties in classroom engagement at school entry. The findings highlight the importance of understanding the intrinsic processes that contribute to difficulties with stage-salient tasks for children who are experiencing interparental discord.