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Sample records for understand model physics

  1. Understanding physics

    CERN Document Server

    Cassidy, David; Rutherford, James

    2002-01-01

    Understanding Physics provides a thorough grounding in contemporary physics while placing physics into its social and historical context Based in large part on the highly respected Project Physics Course developed by two of the authors, it also integrates the results of recent pedagogical research The text thus - teaches about the basic phenomena in the physical world and the concepts developed to explain them - shows that science is a rational human endeavor with a long and continuing tradition, involving many different cultures and people - develops facility in critical thinking, reasoned argumentation, evaluation of evidence, mathematical modeling, and ethical values The treatment emphasizes not only what we know but also how we know it, why we believe it, and what effects that knowledge has - Why do we believe the Earth and planets revolve around the Sun? - Why do we believe that matter is made of atoms? - How do relativity theory and quantum mechanics alter our conception of Nature and in what ways do th...

  2. Differences in spatial understanding between physical and virtual models

    Directory of Open Access Journals (Sweden)

    Lei Sun

    2014-03-01

    Full Text Available In the digital age, physical models are still used as major tools in architectural and urban design processes. The reason why designers still use physical models remains unclear. In addition, physical and 3D virtual models have yet to be differentiated. The answers to these questions are too complex to account for in all aspects. Thus, this study only focuses on the differences in spatial understanding between physical and virtual models. In particular, it emphasizes on the perception of scale. For our experiment, respondents were shown a physical model and a virtual model consecutively. A questionnaire was then used to ask the respondents to evaluate these models objectively and to establish which model was more accurate in conveying object size. Compared with the virtual model, the physical model tended to enable quicker and more accurate comparisons of building heights.

  3. Understanding physics

    CERN Document Server

    Mansfield, Michael

    2011-01-01

    Understanding Physics - Second edition is a comprehensive, yet compact, introductory physics textbook aimed at physics undergraduates and also at engineers and other scientists taking a general physics course. Written with today's students in mind, this text covers the core material required by an introductory course in a clear and refreshing way. A second colour is used throughout to enhance learning and understanding. Each topic is introduced from first principles so that the text is suitable for students without a prior background in physics. At the same time the book is designed to enable

  4. A Framework for Understanding Physics Students' Computational Modeling Practices

    Science.gov (United States)

    Lunk, Brandon Robert

    With the growing push to include computational modeling in the physics classroom, we are faced with the need to better understand students' computational modeling practices. While existing research on programming comprehension explores how novices and experts generate programming algorithms, little of this discusses how domain content knowledge, and physics knowledge in particular, can influence students' programming practices. In an effort to better understand this issue, I have developed a framework for modeling these practices based on a resource stance towards student knowledge. A resource framework models knowledge as the activation of vast networks of elements called "resources." Much like neurons in the brain, resources that become active can trigger cascading events of activation throughout the broader network. This model emphasizes the connectivity between knowledge elements and provides a description of students' knowledge base. Together with resources resources, the concepts of "epistemic games" and "frames" provide a means for addressing the interaction between content knowledge and practices. Although this framework has generally been limited to describing conceptual and mathematical understanding, it also provides a means for addressing students' programming practices. In this dissertation, I will demonstrate this facet of a resource framework as well as fill in an important missing piece: a set of epistemic games that can describe students' computational modeling strategies. The development of this theoretical framework emerged from the analysis of video data of students generating computational models during the laboratory component of a Matter & Interactions: Modern Mechanics course. Student participants across two semesters were recorded as they worked in groups to fix pre-written computational models that were initially missing key lines of code. Analysis of this video data showed that the students' programming practices were highly influenced by

  5. The Effect of Modeling and Visualization Resources on Student Understanding of Physical Hydrology

    Science.gov (United States)

    Marshall, Jilll A.; Castillo, Adam J.; Cardenas, M. Bayani

    2015-01-01

    We investigated the effect of modeling and visualization resources on upper-division, undergraduate and graduate students' performance on an open-ended assessment of their understanding of physical hydrology. The students were enrolled in one of five sections of a physical hydrology course. In two of the sections, students completed homework…

  6. The Role of Computer Modeling in Enhancing Students' Conceptual Understanding of Physics

    Directory of Open Access Journals (Sweden)

    F. Ornek

    2012-04-01

    Full Text Available The purpose of this study was to investigate how the use of the computer simulations program VPython facilitated students’ conceptual understanding of fundamental physical principles and in constructing new knowledge of physics. We focused on students in a calculus-based introductory physics course, based on the Matter and Interactions curriculum of Chabay & Sherwood (2002 at a large state engineering and science university in the USA. A major emphasis of this course was on computer modeling by using VPython to write pro¬grams simulating physical systems. We conducted multiple student interviews, as well as an open-ended exit survey, to find out student views on how creating their own simulations to enhanced-conceptual understanding of physics and in constructing new knowledge of phys¬ics. The results varied in relation to the phases when the interviews were conducted. At the beginning of the course, students viewed the simulation program as a burden. However, dur¬ing the course, students stated that it promoted their knowledge and better conceptual understanding of physical phenomena. We deduce that VPython computer simulations can improve students’ conceptual understanding of fundamental physical concepts and promote construction of new knowledge in physics, once they overcome the initial learning curve associated with the VPython software package.

  7. Understanding many-body physics in one dimension from the Lieb–Liniger model

    International Nuclear Information System (INIS)

    Jiang Yu-Zhu; Chen Yang-Yang; Guan Xi-Wen

    2015-01-01

    This article presents an elementary introduction on various aspects of the prototypical integrable model the Lieb–Liniger Bose gas ranging from the cooperative to the collective features of many-body phenomena. In 1963, Lieb and Liniger first solved this quantum field theory many-body problem using Bethe’s hypothesis, i.e., a particular form of wavefunction introduced by Bethe in solving the one-dimensional Heisenberg model in 1931. Despite the Lieb–Liniger model is arguably the simplest exactly solvable model, it exhibits rich quantum many-body physics in terms of the aspects of mathematical integrability and physical universality. Moreover, the Yang–Yang grand canonical ensemble description for the model provides us with a deep understanding of quantum statistics, thermodynamics, and quantum critical phenomena at the many-body physical level. Recently, such fundamental physics of this exactly solved model has been attracting growing interest in experiments. Since 2004, there have been more than 20 experimental papers that reported novel observations of different physical aspects of the Lieb–Liniger model in the laboratory. So far the observed results are in excellent agreement with results obtained using the analysis of this simplest exactly solved model. Those experimental observations reveal the unique beauty of integrability. (topical review)

  8. Toward a Neurobiological Basis for Understanding Learning in University Modeling Instruction Physics Courses

    Directory of Open Access Journals (Sweden)

    Eric Brewe

    2018-05-01

    Full Text Available Modeling Instruction (MI for University Physics is a curricular and pedagogical approach to active learning in introductory physics. A basic tenet of science is that it is a model-driven endeavor that involves building models, then validating, deploying, and ultimately revising them in an iterative fashion. MI was developed to provide students a facsimile in the university classroom of this foundational scientific practice. As a curriculum, MI employs conceptual scientific models as the basis for the course content, and thus learning in a MI classroom involves students appropriating scientific models for their own use. Over the last 10 years, substantial evidence has accumulated supporting MI's efficacy, including gains in conceptual understanding, odds of success, attitudes toward learning, self-efficacy, and social networks centered around physics learning. However, we still do not fully understand the mechanisms of how students learn physics and develop mental models of physical phenomena. Herein, we explore the hypothesis that the MI curriculum and pedagogy promotes student engagement via conceptual model building. This emphasis on conceptual model building, in turn, leads to improved knowledge organization and problem solving abilities that manifest as quantifiable functional brain changes that can be assessed with functional magnetic resonance imaging (fMRI. We conducted a neuroeducation study wherein students completed a physics reasoning task while undergoing fMRI scanning before (pre and after (post completing a MI introductory physics course. Preliminary results indicated that performance of the physics reasoning task was linked with increased brain activity notably in lateral prefrontal and parietal cortices that previously have been associated with attention, working memory, and problem solving, and are collectively referred to as the central executive network. Critically, assessment of changes in brain activity during the physics

  9. Model reduction and physical understanding of slowly oscillating processes : the circadian cycle.

    Energy Technology Data Exchange (ETDEWEB)

    Goussis, Dimitris A. (Ploutonos 7, Palaio Faliro, Greece); Najm, Habib N.

    2006-01-01

    A differential system that models the circadian rhythm in Drosophila is analyzed with the computational singular perturbation (CSP) algorithm. Reduced nonstiff models of prespecified accuracy are constructed, the form and size of which are time-dependent. When compared with conventional asymptotic analysis, CSP exhibits superior performance in constructing reduced models, since it can algorithmically identify and apply all the required order of magnitude estimates and algebraic manipulations. A similar performance is demonstrated by CSP in generating data that allow for the acquisition of physical understanding. It is shown that the processes driving the circadian cycle are (i) mRNA translation into monomer protein, and monomer protein destruction by phosphorylation and degradation (along the largest portion of the cycle); and (ii) mRNA synthesis (along a short portion of the cycle). These are slow processes. Their action in driving the cycle is allowed by the equilibration of the fastest processes; (1) the monomer dimerization with the dimer dissociation (along the largest portion of the cycle); and (2) the net production of monomer+dimmer proteins with that of mRNA (along the short portion of the cycle). Additional results (regarding the time scales of the established equilibria, their origin, the rate limiting steps, the couplings among the variables, etc.) highlight the utility of CSP for automated identification of the important underlying dynamical features, otherwise accessible only for simple systems whose various suitable simplifications can easily be recognized.

  10. Understanding solid state physics

    CERN Document Server

    Holgate, Sharon Ann

    2009-01-01

    Where Sharon Ann Holgate has succeeded in this book is in packing it with examples of the application of solid state physics to technology. … All the basic elements of solid state physics are covered … . The range of materials is good, including as it does polymers and glasses as well as crystalline solids. In general, the style makes for easy reading. … Overall this book succeeds in showing the relevance of solid state physics to the modern world … .-Contemporary Physics, Vol. 52, No. 2, 2011I was indeed amused and inspired by the wonderful images throughout the book, carefully selected by th

  11. Understanding quantum physics

    International Nuclear Information System (INIS)

    Spillner, Vera

    2011-01-01

    This thesis presents a bundle definition for 'scientific understanding' through which the empirically equivalent interpretations of quantum mechanics can be evaluated with respect to the understanding they generate. The definition of understanding is based on a sufficient and necessary criterion, as well as a bundle of conditions - where a theory can be called most understandable whenever it fulfills the highest number of bundle criteria. Thereby the definition of understanding is based on the one hand on the objective number of criteria a theory fulfills, as well as, on the other hand, on the individual's preference of bundle criteria. Applying the definition onto three interpretations of quantum mechanics, the interpretation of David Bohm appears as most understandable, followed by the interpretation of Tim Maudlin and the Kopenhagen interpretation. These three interpretations are discussed in length in my thesis. (orig.)

  12. Individualized Physical 3-dimensional Kidney Tumor Models Constructed From 3-dimensional Printers Result in Improved Trainee Anatomic Understanding.

    Science.gov (United States)

    Knoedler, Margaret; Feibus, Allison H; Lange, Andrew; Maddox, Michael M; Ledet, Elisa; Thomas, Raju; Silberstein, Jonathan L

    2015-06-01

    To evaluate the effect of 3-dimensionally (3D) printed physical renal models with enhancing masses on medical trainee characterization, localization, and understanding of renal malignancy. Proprietary software was used to import standard computed tomography (CT) cross-sectional imaging into 3D printers to create physical models of renal units with enhancing renal lesions in situ. Six different models were printed from a transparent plastic resin; the normal parenchyma was printed in a clear, translucent plastic, with a red hue delineating the suspicious renal lesion. Medical students, who had completed their first year of training, were given an overview and tasked with completion of RENAL nephrometry scores, separately using CT imaging and 3D models. Trainees were also asked to complete a questionnaire about their experience. Variability between trainees was assessed by intraclass correlation coefficients (ICCs), and kappa statistics were used to compare the trainee to experts. Overall trainee nephrometry score accuracy was significantly improved with the 3D model vs CT scan (P renal mass. Physical 3D models using readily available printing techniques improve trainees' understanding and characterization of individual patients' enhancing renal lesions. Published by Elsevier Inc.

  13. Understanding Laser-Imprint Effects on Plastic-Target Implosions on OMEGA with New Physics Models

    Science.gov (United States)

    Hu, S. X.; Michel, D. T.; Davis, A. K.; Betti, R.; Radha, P. B.; Campbell, E. M.; Froula, D. H.; Stoeckl, C.

    2016-10-01

    Using the state-of-the-art physics models (nonlocal thermal transport, cross-beam energy transfer, and first-principles equation of state) recently implemented in our two-dimensional hydrocode DRACO, we have performed a systematic study of laser-imprint effects on plastic-target implosions on OMEGA by both simulations and experiments. Through varying the laser picket intensity, the imploding shells were set at different adiabats ranging from α = 2 to α = 6 . As the shell adiabat α decreases, we observed: (1) the measured shell thickness at the hot spot emission becomes larger than the uniform prediction; (2) the hot-spot core emits and neutron burn starts earlier than the corresponding 1-D prediction; and (3) the measured neutron yields are significantly reduced from their 1-D designs. Most of these experimental observations are well reproduced by our DRACO simulations with laser imprints. These studies clearly identify that laser imprint is the major cause for target performance degradation of OMEGA implosions of α ignition attempts. This material is based upon work supported by the Department of Energy National Nuclear Security Administration under Award Number DE-NA0001944.

  14. The Effect of Conceptual Change Model in the Senior High School Students’ Understanding and Character in Learning Physics

    Directory of Open Access Journals (Sweden)

    Santyasa I Wayan

    2018-01-01

    Full Text Available Learning physics for senior high school (SMA students is often coloured by misconceptions that hinder students in achieving deep understanding. So a relevant learning model is needed. This study aims to examine the effect of conceptual change model (CCM compared with direct instruction model (DIM on the students’ conceptual understanding and character in the subject area of motion and force. This quasi-experimental research using a non-equivalence pre-test post-test control groups design. The population is 20 classes (738 students of grade X consisted of 8 classes (272 students of SMA 1 Amlapura, 8 classes (256 students of SMA 2 Amlapura, and 6 classes (210 students of SMA 1 Manggis in Karangasem regency in Bali. The random assignment technique is used to assign 6 classes (202 students, or 26.5% of the population. In each school there are set 2 classes each as a CCM group and DIM groups. The data of students’ conceptual understanding is collected by tests, while the characters by questionnaires. To analyse the data a one way MANCOVA statistics was used. The result of the analysis showed that there was a significant difference of effect between CCM group and DIM group on the students’ conceptual understanding and character. The effect of the CCM group is higher than the DIM group on the students’ conceptual understanding and character in learning subject area of motion and force.

  15. ANALYSIS LEARNING MODEL OF DISCOVERY AND UNDERSTANDING THE CONCEPT PRELIMINARY TO PHYSICS LEARNING OUTCOMES SMA

    Directory of Open Access Journals (Sweden)

    Sri Rosepda Sebayang

    2015-12-01

    Full Text Available This study aims: 1 to determine whether the student learning outcomes using discovery learning is better than conventional learning 2 To determine whether the learning outcomes of students who have a high initial concept understanding better then of low initial concept understanding, and 3 to determine the effect of interaction discovery learning and understanding of the initial concept of the learning outcomes of students. The samples in this study was taken by cluster random sampling two classes where class X PIA 3 as a class experiment with applying discovery learning and class X PIA 2 as a control class by applying conventional learning. The instrument used in this study is a test of learning outcomes in the form of multiple-choice comprehension test initial concept description form. The results of research are: 1 learning outcomes of students who were taught with discovery learning is better than the learning outcomes of students who are taught by conventional learning, 2 student learning outcomes with high initial conceptual understanding better than the learning outcomes of students with low initial conceptual understanding, and 3 there was no interaction between discovery learning and understanding of initial concepts for the student learning outcomes.

  16. Reconciling the understanding of 'hydrophobicity' with physics-based models of proteins.

    Science.gov (United States)

    Harris, Robert C; Pettitt, B Montgomery

    2016-03-02

    The idea that a 'hydrophobic energy' drives protein folding, aggregation, and binding by favoring the sequestration of bulky residues from water into the protein interior is widespread. The solvation free energies (ΔGsolv) of small nonpolar solutes increase with surface area (A), and the free energies of creating macroscopic cavities in water increase linearly with A. These observations seem to imply that there is a hydrophobic component (ΔGhyd) of ΔGsolv that increases linearly with A, and this assumption is widely used in implicit solvent models. However, some explicit-solvent molecular dynamics studies appear to contradict these ideas. For example, one definition (ΔG(LJ)) of ΔGhyd is that it is the free energy of turning on the Lennard-Jones (LJ) interactions between the solute and solvent. However, ΔG(LJ) decreases with A for alanine and glycine peptides. Here we argue that these apparent contradictions can be reconciled by defining ΔGhyd to be a near hard core insertion energy (ΔGrep), as in the partitioning proposed by Weeks, Chandler, and Andersen. However, recent results have shown that ΔGrep is not a simple function of geometric properties of the molecule, such as A and the molecular volume, and that the free energy of turning on the attractive part of the LJ potential cannot be computed from first-order perturbation theory for proteins. The theories that have been developed from these assumptions to predict ΔGhyd are therefore inadequate for proteins.

  17. Modeling the effects of multicontextual physics instruction on learner expectations and understanding of force and motion systems

    Science.gov (United States)

    Deese Becht, Sara-Maria Francis

    1999-11-01

    The purpose of this study is two-fold involving both practical and theoretical modeling components. The practical component, an experiential-learning phase, investigated a study population for effects that increasing levels of multicontextual physics activities have on student understanding of Newtonian systems of motion. This contextual-learning model measured learner convictions and non-response gaps and analyzed learner response trends on context, technology, challenge, growth, and success. The theoretical component, a model-building phase, designed a dynamic-knowing model for learning along a range of experiential tasks, from low to high context, monitored for indicators of learning in science and mathematics: learner academic performance and ability, learner control and academic attitude, and a learner non- response gap. This knowing model characterized a learner's process-of-knowing on a less to more expert- like learner-response continuum using performance and perspective indices associated with level of contextual- imagery referent system. Data for the contextual-learning model were collected on 180 secondary subjects: 72 middle and 108 high, with 36 physics subjects as local experts. Subjects were randomly assigned to one of three experimental groups differing only on context level of force and motion activities. Three levels of information were presented through context-based tasks: momentum constancy as inertia, momentum change as impulse, and momentum rate of change as force. The statistical analysis used a multi-level factorial design with repeated measures and discriminate analysis of response-conviction items. Subject grouping criteria included school level, ability level in science and mathematics, gender and race. Assessment criteria used pre/post performance scores, confidence level in physics concepts held, and attitude towards science, mathematics, and technology. Learner indices were computed from logit- transforms applied to learner outcomes

  18. Comparison of Pre-Service Physics Teachers' Conceptual Understanding of Dynamics in Model-Based Scientific Inquiry and Scientific Inquiry Environments

    Science.gov (United States)

    Arslan Buyruk, Arzu; Ogan Bekiroglu, Feral

    2018-01-01

    The focus of this study was to evaluate the impact of model-based inquiry on pre-service physics teachers' conceptual understanding of dynamics. Theoretical framework of this research was based on models-of-data theory. True-experimental design using quantitative and qualitative research methods was carried out for this research. Participants of…

  19. Understanding Students' Motivation in Sport and Physical Education: From the Expectancy-Value Model and Self-Efficacy Theory Perspectives

    Science.gov (United States)

    Gao, Zan; Lee, Amelia M.; Harrison, Louis, Jr.

    2008-01-01

    In this article, the roles of individuals' expectancy beliefs and incentives (i.e., task value, outcome expectancy) in sport and physical education are examined from expectancy-value model and self-efficacy theory perspectives. Overviews of the two theoretical frameworks and the conceptual and measurement issues are provided, followed by a review…

  20. Understanding DSGE models

    CERN Document Server

    Costa Junior, Celso Jose

    2016-01-01

    While the theoretical development of DSGE models is not overly difficult to understand, practical application remains somewhat complex. The literature on this subject has some significant obscure points. This book can be thought of, firstly, as a tool to overcome initial hurdles with this type of modeling. Secondly, by showcasing concrete applications, it aims to persuade incipient researchers to work with this methodology. In principle, this is not a book on macroeconomics in itself, but on tools used in the construction of this sort of models. It strives to present this technique in a detail

  1. Understanding Female Students' Physics Identity Development

    Science.gov (United States)

    Hazari, Zahra

    2017-01-01

    While the gender gap in physics participation is a known problem, practical strategies that may improve the situation are not well understood. As physics education researchers, we draw on evidence to help inform us of what may or may not be working. To this end, physics identity has proven to be a useful framework for understanding and predicting participation in physics. Drawing on data from national surveys of college students, case studies in physics classes, and surveys of undergraduate women in physics, we identify strategies that are predictive of female students' physics identity development from their high school and undergraduate physics experiences. These findings will be discussed as well as future directions for using this research to increase the recruitment of women to physics-related careers. NSF Grant # 1431846.

  2. Understanding Motivators and Barriers to Physical Activity

    Science.gov (United States)

    Patay, Mary E.; Patton, Kevin; Parker, Melissa; Fahey, Kathleen; Sinclair, Christina

    2015-01-01

    The purpose of this study was to understand the factors that influence physical activity among year-round residents in an isolated summer resort community. Specifically, we explored the personal, environmental, social, and culture-specific perceived motivators and barriers to physical activity. Participants were formally interviewed about their…

  3. Promoting Physical Understanding through Peer Mentoring

    Science.gov (United States)

    Nossal, S. M.; Huesmann, A.; Hooper, E.; Moore, C.; Watson, L.; Trestrail, A.; Weber, J.; Timbie, P.; Jacob, A.

    2015-12-01

    The Physics Learning Center at the University of Wisconsin-Madison provides a supportive learning community for students studying introductory physics, as well as teaching and leadership experience for undergraduate Peer Mentor Tutors who receive extensive training and supervision. Many of our Peer Tutors were former Physics Learning Center participants. A central goal of the Physics Learning Center is to address achievement/equity gaps (e.g. race, gender, socio-economic status, disability, age, transfer status, etc.) for undergraduate students pursuing majors and coursework in STEM fields. Students meet twice a week in small learning teams of 3-8 students, facilitated by a trained Peer Mentor Tutor or staff member. These active learning teams focus on discussing core physical concepts and practicing problem-solving. The weekly training of the tutors addresses both teaching and mentoring issues in science education such as helping students to build confidence, strategies for assessing student understanding, and fostering a growth mindset. A second weekly training meeting addresses common misconceptions and strategies for teaching specific physics topics. For non-science majors we have a small Peer Mentor Tutor program for Physics in the Arts. We will discuss the Physics Learning Center's approaches to promoting inclusion, understanding, and confidence for both our participants and Peer Mentor Tutors, as well as examples from the geosciences that can be used to illustrate introductory physics concepts.

  4. Making Introductory Quantum Physics Understandable and Interesting

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 10; Issue 1. Making Introductory Quantum Physics Understandable and Interesting. Ranjana Y Abhang. Classroom Volume 10 Issue 1 January 2005 pp 63-73. Fulltext. Click here to view fulltext PDF. Permanent link:

  5. Understanding search trees via statistical physics

    Indian Academy of Sciences (India)

    ary search tree model (where stands for the number of branches of the search tree), an important problem for data storage in computer science, using a variety of statistical physics techniques that allow us to obtain exact asymptotic results.

  6. Teaching physics and understanding infrared thermal imaging

    Science.gov (United States)

    Vollmer, Michael; Möllmann, Klaus-Peter

    2017-08-01

    Infrared thermal imaging is a very rapidly evolving field. The latest trends are small smartphone IR camera accessories, making infrared imaging a widespread and well-known consumer product. Applications range from medical diagnosis methods via building inspections and industrial predictive maintenance etc. also to visualization in the natural sciences. Infrared cameras do allow qualitative imaging and visualization but also quantitative measurements of the surface temperatures of objects. On the one hand, they are a particularly suitable tool to teach optics and radiation physics and many selected topics in different fields of physics, on the other hand there is an increasing need of engineers and physicists who understand these complex state of the art photonics systems. Therefore students must also learn and understand the physics underlying these systems.

  7. Understanding "Human" Waves: Exploiting the Physics in a Viral Video

    Science.gov (United States)

    Ferrer-Roca, Chantal

    2018-01-01

    Waves are a relevant part of physics that students find difficult to grasp, even in those cases in which wave propagation kinematics can be visualized. This may hinder a proper understanding of sound, light or quantum physics phenomena that are explained using a wave model. So-called "human" waves, choreographed by people, have proved to…

  8. An Application of the Expectancy-Value Model to Understand Adolescents' Performance and Engagement in Physical Education

    Science.gov (United States)

    Yli-Piipari, Sami; Kokkonen, Juha

    2014-01-01

    The study examined the role of motivation in students' performance and engagement in elementary and middle school physical education. Cross-lagged relationships between performance and engagement were investigated across Grades 6-9. A total of 763 (365 girls, 398 boys) Finnish school students (11- to 12-year old) were followed across three years.…

  9. Understandings of 'Modelling'

    DEFF Research Database (Denmark)

    Andresen, Mette

    2007-01-01

    -authentic modelling is also linked with the potentials of exploration of ready-made models as a forerunner for more authentic modelling processes. The discussion includes analysis of an episode of students? work in the classroom, which serves to illustrate how concept formation may be linked to explorations of a non...

  10. Assessing Student Understanding of Physical Hydrology

    Science.gov (United States)

    Castillo, A. J.; Marshall, J.; Cardenas, M. B.

    2012-12-01

    Our objective is to characterize and assess upper division and graduate student thinking by developing and testing an assessment tool for a physical hydrology class. The class' learning goals are: (1) Quantitative process-based understanding of hydrologic processes, (2) Experience with different methods in hydrology, (3) Learning, problem solving, communication skills. These goals were translated into two measurable tasks asked of students in a questionnaire: (1) Describe the significant processes in the hydrological cycle and (2) Describe laws governing these processes. A third question below assessed the students' ability to apply their knowledge: You have been hired as a consultant by __ to (1) assess how urbanization and the current drought have affected a local spring and (2) predict what the effects will be in the future if the drought continues. What information would you need to gather? What measurements would you make? What analyses would you perform? Student and expert responses to the questions were then used to develop a rubric to score responses. Using the rubric, 3 researchers independently blind-coded the full set of pre and post artifacts, resulting in 89% inter-rater agreement on the pre-tests and 83% agreement on the post-tests. We present student scores to illustrate the use of the rubric and to characterize student thinking prior to and following a traditional course. Most students interpreted Q1 in terms of physical processes affecting the water cycle, the primary organizing framework for hydrology, as intended. On the pre-test, one student scored 0, indicating no response, on this question. Twenty students scored 1, indicating rudimentary understanding, 2 students scored a 2, indicating a basic understanding, and no student scored a 3. Student scores on this question improved on the post-test. On the 22 post-tests that were blind scored, 11 students demonstrated some recognition of concepts, 9 students showed a basic understanding, and 2

  11. What makes process models understandable?

    NARCIS (Netherlands)

    Mendling, J.; Reijers, H.A.; Cardoso, J.; Alonso, G.; Dadam, P.; Rosemann, M.

    2007-01-01

    Despite that formal and informal quality aspects are of significant importance to business process modeling, there is only little empirical work reported on process model quality and its impact factors. In this paper we investigate understandability as a proxy for quality of process models and focus

  12. Physical modeling of rock

    International Nuclear Information System (INIS)

    Cheney, J.A.

    1981-01-01

    The problems of statisfying similarity between a physical model and the prototype in rock wherein fissures and cracks place a role in physical behavior is explored. The need for models of large physical dimensions is explained but also testing of models of the same prototype over a wide range of scales is needed to ascertain the influence of lack of similitude of particular parameters between prototype and model. A large capacity centrifuge would be useful in that respect

  13. The role of mathematics for physics teaching and understanding

    Science.gov (United States)

    Pospiech, Gesche; Eylon, BatSheva; Bagno, Esther; Lehavi, Yaron; Geyer, Marie-Annette

    2016-05-01

    -1That mathematics is the "language of physics" implies that both areas are deeply interconnected, such that often no separation between "pure" mathematics and "pure" physics is possible. To clarify their interplay a technical and a structural role of mathematics can be distinguished. A thorough understanding of this twofold role in physics is also important for shaping physics education especially with respect to teaching the nature of physics. Herewith the teachers and their pedagogical content knowledge play an important role. Therefore we develop a model of PCK concerning the interplay of mathematics and physics in order to provide a theoretical framework for the views and teaching strategies of teachers. In an exploratory study four teachers from Germany and four teachers from Israel have been interviewed concerning their views and its transfer to teaching physics. Here we describe the results from Germany. Besides general views and knowledge held by all or nearly all teachers we also observe specific individual focus depending on the teachers' background and experiences. The results fit well into the derived model of PCK.

  14. Identification of physical models

    DEFF Research Database (Denmark)

    Melgaard, Henrik

    1994-01-01

    of the model with the available prior knowledge. The methods for identification of physical models have been applied in two different case studies. One case is the identification of thermal dynamics of building components. The work is related to a CEC research project called PASSYS (Passive Solar Components......The problem of identification of physical models is considered within the frame of stochastic differential equations. Methods for estimation of parameters of these continuous time models based on descrete time measurements are discussed. The important algorithms of a computer program for ML or MAP...... design of experiments, which is for instance the design of an input signal that are optimal according to a criterion based on the information provided by the experiment. Also model validation is discussed. An important verification of a physical model is to compare the physical characteristics...

  15. Understanding Hemophilia. Implications for the Physical Educator.

    Science.gov (United States)

    Coelho, Jeffrey D.

    1998-01-01

    Describes hemophilia and ways to provide appropriate physical education experiences to children with hemophilia. The article focuses on what hemophilia is, how to treat hemophilia, benefits of physical activity, how to teach children with hemophilia, choosing and modifying sports and activities, and safety and emergency situations. (SM)

  16. Understanding quantum physics; Verstehen in der Quantenphysik

    Energy Technology Data Exchange (ETDEWEB)

    Spillner, Vera

    2011-07-01

    This thesis presents a bundle definition for 'scientific understanding' through which the empirically equivalent interpretations of quantum mechanics can be evaluated with respect to the understanding they generate. The definition of understanding is based on a sufficient and necessary criterion, as well as a bundle of conditions - where a theory can be called most understandable whenever it fulfills the highest number of bundle criteria. Thereby the definition of understanding is based on the one hand on the objective number of criteria a theory fulfills, as well as, on the other hand, on the individual's preference of bundle criteria. Applying the definition onto three interpretations of quantum mechanics, the interpretation of David Bohm appears as most understandable, followed by the interpretation of Tim Maudlin and the Kopenhagen interpretation. These three interpretations are discussed in length in my thesis. (orig.)

  17. The role of mathematics for physics teaching and understanding

    International Nuclear Information System (INIS)

    Pospiech, G; Geyer, M.A.; Eylon, B.; Bagno, E.; Lehavi, Y.

    2015-01-01

    That mathematics is the “language of physics” implies that both areas are deeply interconnected, such that often no separation between “pure” mathematics and “pure” physics is possible. To clarify their interplay a technical and a structural role of mathematics can be distinguished. A thorough understanding of this twofold role in physics is also important for shaping physics education especially with respect to teaching the nature of physics. Herewith the teachers and their pedagogical content knowledge play an important role. Therefore we develop a model of PCK concerning the interplay of mathematics and physics in order to provide a theoretical framework for the views and teaching strategies of teachers. In an exploratory study four teachers from Germany and four teachers from Israel have been interviewed concerning their views and its transfer to teaching physics. Here we describe the results from Germany. Besides general views and knowledge held by all or nearly all teachers we also observe specific individual focus depending on the teachers’ background and experiences. The results fit well into the derived model of PCK.

  18. Literature Review of Dredging Physical Models

    Science.gov (United States)

    This U.S. Army Engineer Research and Development Center, Coastal and Hydraulics Laboratory, special report presents a review of dredging physical ...model studies with the goal of understanding the most current state of dredging physical modeling, understanding conditions of similitude used in past...studies, and determining whether the flow field around a dredging operation has been quantified. Historical physical modeling efforts have focused on

  19. Atomistic and holistic understanding in physics

    International Nuclear Information System (INIS)

    Bohm, A.

    1992-01-01

    Understanding means always reduction to the simpler. In the atomistic understanding the reduction is to the simpler objects. One asks the question: what does it consist of? For instance, one asks: What does the molecule consist of? and the answer is: The molecule consists of electrons and nuclei. Or: what does the nucleus consist of? And the answer is: The nucleus consists of protons and neutrons. The parts in the atomistic understanding are the constituents. In the holistic understanding, the reduction is to the simpler functions, the simpler motions. One asks the question: What does it do? What does the molecule do? What does the nucleus do? And the answer is: The molecule rotates and oscillates. The nucleus rotates and oscillates

  20. Understanding the barriers to and reasons for physical exercise ...

    African Journals Online (AJOL)

    African Journal for Physical Activity and Health Sciences ... improving physical health, having confidence with their appearance and improving mental health. ... health benefits, it is important to understand the exercise behaviour of students.

  1. Understanding the physics of changing mass phenomena

    NARCIS (Netherlands)

    Ellermeijer, A.L.

    2008-01-01

    Changing mass phenomena, like a falling chain or a bungee jumper, might give surprising results, even for experienced physicists. They have resulted in hot discussions in journals, in which for instance Physics professors claim the impossibility of an acceleration larger then g in case of a bungee

  2. Models in physics teaching

    DEFF Research Database (Denmark)

    Kneubil, Fabiana Botelho

    2016-01-01

    In this work we show an approach based on models, for an usual subject in an introductory physics course, in order to foster discussions on the nature of physical knowledge. The introduction of elements of the nature of knowledge in physics lessons has been emphasised by many educators and one uses...... the case of metals to show the theoretical and phenomenological dimensions of physics. The discussion is made by means of four questions whose answers cannot be reached neither for theoretical elements nor experimental measurements. Between these two dimensions it is necessary to realise a series...... of reasoning steps to deepen the comprehension of microscopic concepts, such as electrical resistivity, drift velocity and free electrons. When this approach is highlighted, beyond the physical content, aspects of its nature become explicit and may improve the structuring of knowledge for learners...

  3. Physical models of cell motility

    CERN Document Server

    2016-01-01

    This book surveys the most recent advances in physics-inspired cell movement models. This synergetic, cross-disciplinary effort to increase the fidelity of computational algorithms will lead to a better understanding of the complex biomechanics of cell movement, and stimulate progress in research on related active matter systems, from suspensions of bacteria and synthetic swimmers to cell tissues and cytoskeleton.Cell motility and collective motion are among the most important themes in biology and statistical physics of out-of-equilibrium systems, and crucial for morphogenesis, wound healing, and immune response in eukaryotic organisms. It is also relevant for the development of effective treatment strategies for diseases such as cancer, and for the design of bioactive surfaces for cell sorting and manipulation. Substrate-based cell motility is, however, a very complex process as regulatory pathways and physical force generation mechanisms are intertwined. To understand the interplay between adhesion, force ...

  4. Framework for understanding LENR processes, using conventional condensed matter physics

    International Nuclear Information System (INIS)

    Chubb, Scott R.

    2006-01-01

    Conventional condensed matter physics provides a unifying framework for understanding low-energy nuclear reactions (LENRs) in solids. In the paper, standard many-body physics techniques are used to illustrate this fact. Specifically, the paper shows that formally the theories by Schwinger, Hagelstein, and Chubb and Chubb (C and C), all can be related to a common set of equations, associated with reaction rate and energy transfer, through a standard many-body physics procedure (R-matrix theory). In each case, particular forms of coherence are used that, implicitly provide a mechanism for understanding how LENRs can proceed without. the emission of high-energy particles. In addition, additional ideas, associated with Conventional Condensed Matter physics, are used to extend the earlier ion band state (IBS) model by C and C. The general model clarifies the origin of coherent. processes that initiate LENRs, through the onset of ion conduction that can occur through ionic fluctuations in nano-scale crystals. In the case of PdD x , these fluctuations begin to occur as x → 1 in sub-lattice structures with characteristic dimensions of 60 nm. The resulting LENRs are triggered by the polarization between injected d's and electrons (immediately above the Fermi energy) that takes place in finite-size PdD crystals. During the prolonged charging of PdD x the applied, external electric field induces these fluctuations through a form of Zener tunneling that mimics the kind of tunneling, predicted by Zener, that is responsible for possible conduction (referred to as Zener-electric breakdown) in insulators. But because the fluctuations are ionic and they occur in PdD, nano-scale structures, a more appropriate characterization is Zener-ionic breakdown in nano-crystalline PdD. Using the underlying dynamics, it is possible to relate triggering times that are required for the initiation of the effect, to crystal size and externally applied fields. (authors)

  5. Framework for understanding LENR processes, using conventional condensed matter physics

    Energy Technology Data Exchange (ETDEWEB)

    Chubb, Scott R. [Research Systems Inc., 9822 Pebble Weigh Ct., Burke VA 22015-3378 (United States)

    2006-07-01

    Conventional condensed matter physics provides a unifying framework for understanding low-energy nuclear reactions (LENRs) in solids. In the paper, standard many-body physics techniques are used to illustrate this fact. Specifically, the paper shows that formally the theories by Schwinger, Hagelstein, and Chubb and Chubb (C and C), all can be related to a common set of equations, associated with reaction rate and energy transfer, through a standard many-body physics procedure (R-matrix theory). In each case, particular forms of coherence are used that, implicitly provide a mechanism for understanding how LENRs can proceed without. the emission of high-energy particles. In addition, additional ideas, associated with Conventional Condensed Matter physics, are used to extend the earlier ion band state (IBS) model by C and C. The general model clarifies the origin of coherent. processes that initiate LENRs, through the onset of ion conduction that can occur through ionic fluctuations in nano-scale crystals. In the case of PdD{sub x}, these fluctuations begin to occur as x {yields} 1 in sub-lattice structures with characteristic dimensions of 60 nm. The resulting LENRs are triggered by the polarization between injected d's and electrons (immediately above the Fermi energy) that takes place in finite-size PdD crystals. During the prolonged charging of PdD{sub x} the applied, external electric field induces these fluctuations through a form of Zener tunneling that mimics the kind of tunneling, predicted by Zener, that is responsible for possible conduction (referred to as Zener-electric breakdown) in insulators. But because the fluctuations are ionic and they occur in PdD, nano-scale structures, a more appropriate characterization is Zener-ionic breakdown in nano-crystalline PdD. Using the underlying dynamics, it is possible to relate triggering times that are required for the initiation of the effect, to crystal size and externally applied fields. (authors)

  6. Excellence in Physics Education Award: Modeling Theory for Physics Instruction

    Science.gov (United States)

    Hestenes, David

    2014-03-01

    All humans create mental models to plan and guide their interactions with the physical world. Science has greatly refined and extended this ability by creating and validating formal scientific models of physical things and processes. Research in physics education has found that mental models created from everyday experience are largely incompatible with scientific models. This suggests that the fundamental problem in learning and understanding science is coordinating mental models with scientific models. Modeling Theory has drawn on resources of cognitive science to work out extensive implications of this suggestion and guide development of an approach to science pedagogy and curriculum design called Modeling Instruction. Modeling Instruction has been widely applied to high school physics and, more recently, to chemistry and biology, with noteworthy results.

  7. Beyond Standard Model Physics

    Energy Technology Data Exchange (ETDEWEB)

    Bellantoni, L.

    2009-11-01

    There are many recent results from searches for fundamental new physics using the TeVatron, the SLAC b-factory and HERA. This talk quickly reviewed searches for pair-produced stop, for gauge-mediated SUSY breaking, for Higgs bosons in the MSSM and NMSSM models, for leptoquarks, and v-hadrons. There is a SUSY model which accommodates the recent astrophysical experimental results that suggest that dark matter annihilation is occurring in the center of our galaxy, and a relevant experimental result. Finally, model-independent searches at D0, CDF, and H1 are discussed.

  8. Understanding physical activity in adults with type 2 diabetes after completing an exercise intervention trial: A mediation model of self-efficacy and autonomous motivation.

    Science.gov (United States)

    Sweet, Shane N; Fortier, Michelle S; Guérin, Eva; Tulloch, Heather; Sigal, Ronald J; Kenny, Glen P; Reid, Robert D

    2009-08-01

    This study was set out to test if autonomous motivation mediated the relationship between self-efficacy and 12-month physical activity (PA) in adults with type 2 diabetes involved in a randomized exercise trial. Participants (n = 234) completed questionnaires measuring barrier self-efficacy at 3 months, autonomous motivation at 6 months, and PA at 12 months. A mediational analysis of longitudinal data revealed that autonomous motivation mediated the relationship between barrier-self-efficacy and PA. High barrier self-efficacy can therefore help predict 12-month PA in adults with type 2 diabetes, although this effect is attenuated by autonomous motivation. Hence, participating in PA for autonomous reasons such as by choice and/or for fun further explains PA at 12 months in this population. Results of this study extend our understanding of the motivational constructs involved in PA in the maintenance phase. This study has important theoretical implications in that it helps to organize and consolidate well-known correlates of PA by proposing a temporal relationship between them that could be tailored in interventions.

  9. Promoting the Understanding of Mathematics in Physics at Secondary Level

    Science.gov (United States)

    Thompson, Alaric

    2016-01-01

    This article explores some of the common mathematical difficulties that 11- to 16-year-old students experience with respect to their learning of physics. The definition of "understanding" expressed in the article is in the sense of transferability of mathematical skills from topic to topic within physics as well as between the separate…

  10. Physics education: Understanding the barriers for young women in Ontario

    Science.gov (United States)

    Mainhood, Lindsay Ann

    In nearly all countries of the world, at every level of education, physics as a field of science is failing to recruit and retain women. This phenomenon is believed to relate to girls' educational experiences from K-12, but the reasons for the gender gap in physics are not fully understood. The purpose of this phenomenological research is to explore and understand the barriers encountered by Ontario female high school students during their physics education and the meanings attributed to those barriers by these young women. This research is guided by social cognitive career theory (SCCT) and uses the concept of physics identity as a lens through which the influence of contextual barriers can be understood. Nine participants, selected via snowball sampling from an Eastern Ontario university, together participated in four semi-structured focus group meetings and individually participated in a single in-depth, one-on-one interview. Audio data was transcribed verbatim and analyzed using a general inductive approach. Emergent themes are descriptively presented as the findings of the research study: perceiving the high school physics experience, experiencing high school physics education, and identity and gender in the high school physics experience. Sub-themes presented include limited prior experiences, negative perceptions of physics, images of physics learners, decision-making, reactions to pedagogy, learning needs, physics identity, gender-dependent influences, and making meaning of the experiences in high school physics. The shared experience of high school physics education for young women is understood as both a richly challenging and rewarding experience. Based on the findings of this research, recommendations are made for practical and research settings, and for future work in this area. Drawing on literature on underrepresentation of women in physics, this research contributes to the physics education research community and beyond; it offers voices of Ontario

  11. Understanding the Models of Grammar

    OpenAIRE

    Mahaputri, Ratna Andhika

    2013-01-01

    This article provides comprehensive explanation about several models of grammar. The first model of grammar which is explained is considered from the functional grammar and associated with the American linguist Noam Chomsky that is Transformational Grammar. This model of grammar is consisted of three components they are phrase structure rule, the lexicon, and transformation. The second model of grammar which is explained in this article is Minimalist Grammar. This article also compares her...

  12. Physical understanding of the tropical cyclone wind-pressure relationship.

    Science.gov (United States)

    Chavas, Daniel R; Reed, Kevin A; Knaff, John A

    2017-11-08

    The relationship between the two common measures of tropical cyclone intensity, the central pressure deficit and the peak near-surface wind speed, is a long-standing problem in tropical meteorology that has been approximated empirically yet lacks physical understanding. Here we provide theoretical grounding for this relationship. We first demonstrate that the central pressure deficit is highly predictable from the low-level wind field via gradient wind balance. We then show that this relationship reduces to a dependence on two velocity scales: the maximum azimuthal-mean azimuthal wind speed and half the product of the Coriolis parameter and outer storm size. This simple theory is found to hold across a hierarchy of models spanning reduced-complexity and Earth-like global simulations and observations. Thus, the central pressure deficit is an intensity measure that combines maximum wind speed, storm size, and background rotation rate. This work has significant implications for both fundamental understanding and risk analysis, including why the central pressure better explains historical economic damages than does maximum wind speed.

  13. Osteosarcoma models : understanding complex disease

    NARCIS (Netherlands)

    Mohseny, Alexander Behzad

    2012-01-01

    A mesenchymal stem cell (MSC) based osteosarcoma model was established. The model provided evidence for a MSC origin of osteosarcoma. Normal MSCs transformed spontaneously to osteosarcoma-like cells which was always accompanied by genomic instability and loss of the Cdkn2a locus. Accordingly loss of

  14. Trying to understand management models

    DEFF Research Database (Denmark)

    Jonker, Jan; van Pijkeren, Michel; Eskildsen, Jacob Kjær

    2009-01-01

    in common but also how they can be distinguished from each other. Our aim of this exploration is to grasp the more fundamental, conceptual and theoretical aspects of management models. This exploration is guided by a number of questions. How can management models be classified and categorised? What......In the previous chapters a number of management models have been presented. What ties them together is the fact that companies have created them in order to address present and future organisational challenges. We have chosen to show them as they are, with as much as possible respect to differences...

  15. A Social Identity Approach to Understanding and Promoting Physical Activity.

    Science.gov (United States)

    Stevens, Mark; Rees, Tim; Coffee, Pete; Steffens, Niklas K; Haslam, S Alexander; Polman, Remco

    2017-10-01

    Against the backdrop of a global physical inactivity crisis, attempts to both understand and positively influence physical activity behaviours are characterized by a focus on individual-level factors (e.g. cognitions, attitudes, motivation). We outline a new perspective, drawn from an emerging body of work exploring the applicability of social identity and self-categorization theories to domains of sport and health, from which to understand and address this pervasive problem. This social identity approach suggests that the groups to which people belong can be, and often are, incorporated into their sense of self and, through this, are powerful determinants of physical activity-related behaviour. We start by reviewing the current state of physical activity research and highlighting the potential for the social identity approach to help understand how social factors influence these behaviours. Next, we outline the theoretical underpinnings of the social identity approach and provide three key examples that speak to the analytical and practical value of the social identity approach in physical activity settings. Specifically, we argue that social identity (1) can be harnessed to promote engagement in physical activity, (2) underpins exercise group behaviour, and (3) underpins effective leadership in exercise settings. We conclude by identifying prospects for a range of theory-informed research developments.

  16. Chapter 2: Theoretical Models for Understanding Physical Activity Behavior among Children and Adolescents--Social Cognitive Theory and Self-Determination Theory

    Science.gov (United States)

    Motl, Robert W.

    2007-01-01

    The study of physical activity behavior in youth generally lacks a sufficient theoretical foundation for examining variables that influence that behavior. This is a major limitation because theory guides the search for determinants of behavior and the subsequent interplay between research findings and application. Theory offers a systematically…

  17. Physics and the Art of Dance - Understanding Movement

    Science.gov (United States)

    Swope, Kenneth Laws

    2005-03-01

    Written by a physicist with professional dance training, Physics and the Art of Dance explains how dancers can achieve better, safer performances through an understanding of physics in motion. Using simple, non-technical terms, Kenneth Laws combines his knowledge of both physics and dance to describe how the laws of gravity, momentum, and energy affect dancing bodies. The book explores the natural laws that govern the subtleties of balance, the techniques of leaps and pirouettes, and the impressive lifts and turns executed by ballet partners. Finally, Laws offers insight into two current discussions in the dance world--the effect of body size on ballet technique, and the relationship between science and the art of dance. Beautiful, original stop-action photographs by Martha Swope, along with clear diagrams, illustrate the concepts described in the text. Plus, an intriguing "puzzler" at the beginning of each chapter provides an engaging entree into the topics presented. For those who want a more advanced understanding of the physics, extensive appendices are provided. This new book combines the best features of Laws's widely acclaimed The Physics of Dance and Physics, Dance, and the Pas de Deux by Laws and Cynthia Harvey. Its expert application of the basic principles of physics to the art of dance will be an invaluable resource for dancers and dance instructors and will open a new level of appreciation for lovers of the form. It will also appeal to physicists who seek to include the arts in their scientific pursuits.

  18. CGILS : Results from the first phase of an international project to understand the physical mechanisms of low cloud feedbacks in single column models

    NARCIS (Netherlands)

    Zhang, M.; Bretherton, C.S.; Blossey, P.N.; Austin, P.H.; Bacmeister, J.T.; Bony, S.; Brient, F.; Cheedela, S.K.; Cheng, A.; Del Genio, A.D.; De Roode, S.R.; Endo, S.; Franklin, C.N.; Golaz, J.C.; Hannay, C.; Heus, T.; Isotta, F.A.; Dufresne, J.L.; Kang, I.S.; Kawai, H.; Köhler, M.; Larson, V.E.; Liu, Y.; Lock, A.P.; Lohmann, U.; Khairoutdinov, M.F.; Molod, A.M.; Neggers, R.A.J.; Rasch, P.; Sandu, I.; Senkbeil, R.; Siebesma, A.P.; Siegenthaler-Le Drian, C.; Stevens, B.; Suarez, M.J.; Xu, K.M.; Von Salzen, K.; Webb, M.J.; Wolf, A.; Zhao, M.

    2013-01-01

    CGILS—the CFMIP-GASS Intercomparison of Large Eddy Models (LESs) and single column models (SCMs)—investigates the mechanisms of cloud feedback in SCMs and LESs under idealized climate change perturbation. This paper describes the CGILS results from 15 SCMs and 8 LES models. Three cloud regimes over

  19. Understanding transport barriers through modelling

    International Nuclear Information System (INIS)

    Rozhansky, V

    2004-01-01

    Models of radial electric field formation are discussed and compared with the results of numerical simulations from fluid transport codes and Monte Carlo codes. A comparison of the fluid and Monte Carlo codes is presented. A conclusion is arrived at that all the simulations do not predict any bifurcation of the electric field, i.e. no bifurcation of poloidal rotation from low to high Mach number values is obtained. In most of the simulations, the radial electric field is close to the neoclassical electric field. The deviation from neoclassical electric field at the separatrix due to the existence of a transitional viscous layer is discussed. Scalings for the shear of the poloidal rotation are checked versus simulation results. It is demonstrated that assuming the critical shear to be of the order of 10 5 s -1 , it is possible to obtain a L-H transition power scaling close to that observed in the experiment. The dependence of the threshold on the magnetic field direction, pellet injection, aspect ratio and other factors are discussed on the basis of existing simulations. Transport codes where transport coefficients depend on the turbulence level and scenario simulations of L-H transition are analysed. However, the details of gyrofluid and gyrokinetic modelling should be discussed elsewhere. Simulations of internal transport barrier (ITB) formation are discussed as well as factors responsible for ITB formation

  20. Developmental Patterns in the Understanding of Social and Physical Transitivity.

    Science.gov (United States)

    Markovits, Henry; Dumas, Claude

    1999-01-01

    Two studies examined developmental patterns in understanding physical and social transitivity in 6- to 11-year olds. Findings revealed no significant correlations between social judgments and judgments concerning length. Results suggested that children possess two distinct strategies for making transitive judgments that correspond to the logical…

  1. Understanding physical activity promotion in physiotherapy practice: A qualitative study.

    Science.gov (United States)

    Lowe, Anna; Littlewood, Chris; McLean, Sionnadh

    2018-06-01

    Physical inactivity is a major public health issue and healthcare professionals are encouraged to promote physical activity during routine patient contacts in order to reduce non-communicable diseases and enhance individuals' quality of life. Little is known about physical activity promotion in physiotherapy practice in the UK. The aim of this study was to better understand physiotherapists' experience of physical activity promotion in clinical practice. A qualitative study was undertaken comprising 12 telephone interviews with participants using a quota sampling approach. The qualitative data was analysed using a thematic analysis approach and written up according to COREQ guidelines. Four themes were identified (1) Current physiotherapy practice (2) Barriers to, and facilitators of physical activity promotion, (3) Exercise or physical activity? and (4) Functional restoration versus general wellbeing. Physiotherapists use routine clinical contacts to discuss physical activity. However, brief interventions are not consistently used and no common framework to guide physical activity promotion was identified. Approaches appear to be inconsistent and informal and focus largely on short-term restoration of function rather than health promotion. There is scope to improve practice in line with current guidance to maximise potential impact on inactivity. Copyright © 2018 Elsevier Ltd. All rights reserved.

  2. Teaching Physics for Conceptual Understanding Exemplified for Einstein's Special Relativity

    Science.gov (United States)

    Undreiu, Lucian M.

    2006-12-01

    In most liberal arts colleges the prerequisites for College Physics, Introductory or Calculus based, are strictly related to Mathematics. As a state of fact, the majorities of the students perceive Physics as a conglomerate of mathematical equations, a collection of facts to be memorized and they regard Physics as one of the most difficult subjects. A change of this attitude towards Physics, and Science in general, is intrinsically connected with the promotion of conceptual understanding and stimulation of critical thinking. In such an environment, the educators are facilitators, rather than the source of knowledge. One good way of doing this is to challenge the students to think about what they see around them and to connect physics with the real world. Motivation occurs when students realize that what was learned is interesting and relevant. Visual teaching aids such as educational videos or computer simulations, as well as computer-assisted experiments, can greatly enhance the effectiveness of a science lecture or laboratory. Difficult topics can be discussed through animated analogies. Special Relativity is recognized as a challenging topic and is probably one of the most misunderstood theories of Physics. While understanding Special Relativity requires a detachment from ordinary perception and every day life notions, animated analogies can prove to be very successful in making difficult topics accessible.

  3. Draw Your Physics Homework? Art as a Path to Understanding in Physics Teaching

    Science.gov (United States)

    van der Veen, Jatila

    2012-01-01

    The persistent fear of physics by learners motivated the author to take action to increase all students' interest in the subject via a new curriculum for introductory college physics that applies Greene's model of Aesthetic Education to the study of contemporary physics, utilizing symmetry as the mathematical foundation of physics as well as the…

  4. Mediating relationship of differential products in understanding integration in introductory physics

    Science.gov (United States)

    Amos, Nathaniel; Heckler, Andrew F.

    2018-01-01

    In the context of introductory physics, we study student conceptual understanding of differentials, differential products, and integrals and possible pathways to understanding these quantities. We developed a multiple choice conceptual assessment employing a variety of physical contexts probing physical understanding of these three quantities and administered the instrument to over 1000 students in first and second semester introductory physics courses. Using a regression-based mediation analysis with conceptual understanding of integration as the dependent variable, we found evidence consistent with a simple mediation model: the relationship between differentials scores and integral scores may be mediated by the understanding of differential products. The indirect effect (a quantifiable metric of mediation) was estimated as a b =0.29 , 95% CI [0.25, 0.33] for N =1102 Physics 1 students, and a b =0.27 , 95% CI [0.14, 0.48] for N =65 Physics 2 students. We also find evidence that the physical context of the questions can be an important factor. These results imply that for introductory physics courses, instructional emphasis first on differentials then on differential products in a variety of contexts may in turn promote better integral understanding.

  5. Students' Energy Understanding Across Biology, Chemistry, and Physics Contexts

    Science.gov (United States)

    Opitz, S. T.; Neumann, K.; Bernholt, S.; Harms, U.

    2017-07-01

    Energy is considered both as a disciplinary core idea and as a concept cutting across science disciplines. Most previous approaches studied progressing energy understanding in specific disciplinary contexts, while disregarding the relation of understanding across them. Hence, this study provides a systematic analysis of cross-disciplinary energy learning. On the basis of a cross-sectional study with n = 742 students from grades 6, 8, and 10, we analyze students' progression in understanding energy across biology, chemistry, and physics contexts. The study is guided by three hypothetical scenarios that describe how the connection between energy understanding in the three disciplinary contexts changes across grade levels. These scenarios are compared using confirmatory factor analysis (CFA). The results suggest that, from grade 6 to grade 10, energy understanding in the three disciplinary contexts is highly interrelated, thus indicating a parallel progression of energy understanding in the three disciplinary contexts. In our study, students from grade 6 onwards appeared to have few problems to apply one energy understanding across the three disciplinary contexts. These findings were unexpected, as previous research concluded that students likely face difficulties in connecting energy learning across disciplinary boundaries. Potential reasons for these results and the characteristics of the observed cross-disciplinary energy understanding are discussed in the light of earlier findings and implications for future research, and the teaching of energy as a core idea and a crosscutting concept are addressed.

  6. CGILS: Results from the First Phase of an International Project to Understand the Physical Mechanisms of Low Cloud Feedbacks in Single Column Models

    Science.gov (United States)

    Zhang, Minghua; Bretherton, Christopher S.; Blossey, Peter N.; Austin, Phillip H.; Bacmeister, Julio T.; Bony, Sandrine; Brient, Florent; Cheedela, Suvarchal K.; Cheng, Anning; DelGenio, Anthony; hide

    2013-01-01

    1] CGILS-the CFMIP-GASS Intercomparison of Large Eddy Models (LESs) and single column models (SCMs)-investigates the mechanisms of cloud feedback in SCMs and LESs under idealized climate change perturbation. This paper describes the CGILS results from 15 SCMs and 8 LES models. Three cloud regimes over the subtropical oceans are studied: shallow cumulus, cumulus under stratocumulus, and well-mixed coastal stratus/stratocumulus. In the stratocumulus and coastal stratus regimes, SCMs without activated shallow convection generally simulated negative cloud feedbacks, while models with active shallow convection generally simulated positive cloud feedbacks. In the shallow cumulus alone regime, this relationship is less clear, likely due to the changes in cloud depth, lateral mixing, and precipitation or a combination of them. The majority of LES models simulated negative cloud feedback in the well-mixed coastal stratus/stratocumulus regime, and positive feedback in the shallow cumulus and stratocumulus regime. A general framework is provided to interpret SCM results: in a warmer climate, the moistening rate of the cloudy layer associated with the surface-based turbulence parameterization is enhanced; together with weaker large-scale subsidence, it causes negative cloud feedback. In contrast, in the warmer climate, the drying rate associated with the shallow convection scheme is enhanced. This causes positive cloud feedback. These mechanisms are summarized as the "NESTS" negative cloud feedback and the "SCOPE" positive cloud feedback (Negative feedback from Surface Turbulence under weaker Subsidence-Shallow Convection PositivE feedback) with the net cloud feedback depending on how the two opposing effects counteract each other. The LES results are consistent with these interpretations

  7. Understanding student use of differentials in physics integration problems

    Directory of Open Access Journals (Sweden)

    Dehui Hu

    2013-07-01

    Full Text Available This study focuses on students’ use of the mathematical concept of differentials in physics problem solving. For instance, in electrostatics, students need to set up an integral to find the electric field due to a charged bar, an activity that involves the application of mathematical differentials (e.g., dr, dq. In this paper we aim to explore students’ reasoning about the differential concept in physics problems. We conducted group teaching or learning interviews with 13 engineering students enrolled in a second-semester calculus-based physics course. We amalgamated two frameworks—the resources framework and the conceptual metaphor framework—to analyze students’ reasoning about differential concept. Categorizing the mathematical resources involved in students’ mathematical thinking in physics provides us deeper insights into how students use mathematics in physics. Identifying the conceptual metaphors in students’ discourse illustrates the role of concrete experiential notions in students’ construction of mathematical reasoning. These two frameworks serve different purposes, and we illustrate how they can be pieced together to provide a better understanding of students’ mathematical thinking in physics.

  8. Physical Education Teacher Educator's Perceptions toward and Understanding of K-12 Online Physical Education

    Science.gov (United States)

    Daum, David N.; Woods, Amelia M.

    2015-01-01

    K-12 online physical education (OLPE) is as an educational opportunity in at least 30 states in the US (NASPE, 2006; 2010; 2012). The purpose of this study was to examine physical education teacher educators' perceptions toward and understanding of K-12 OLPE. Bandura's Social Cognitive Theory (1986) served as the theoretical framework for this…

  9. Learning about a Level Physics Students' Understandings of Particle Physics Using Concept Mapping

    Science.gov (United States)

    Gourlay, H.

    2017-01-01

    This paper describes a small-scale piece of research using concept mapping to elicit A level students' understandings of particle physics. Fifty-nine year 12 (16- and 17 year-old) students from two London schools participated. The exercise took place during school physics lessons. Students were instructed how to make a concept map and were…

  10. Progress in wall turbulence 2 understanding and modelling

    CERN Document Server

    Jimenez, Javier; Marusic, Ivan

    2016-01-01

    This is the proceedings of the ERCOFTAC Workshop on Progress in Wall Turbulence: Understanding and Modelling, that was held in Lille, France from June 18 to 20, 2014. The workshop brought together world specialists of near wall turbulence and stimulated exchanges between them around up-to-date theories, experiments, simulations and numerical models. This book contains a coherent collection of recent results on near wall turbulence including theory, new experiments, DNS, and modeling with RANS, LES.The fact that both physical understanding and modeling by different approaches are addressed by the best specialists in a single workshop is original.

  11. Problems in physical modeling of magnetic materials

    International Nuclear Information System (INIS)

    Della Torre, E.

    2004-01-01

    Physical modeling of magnetic materials should give insights into the basic processes involved and should be able to extrapolate results to new situations that the models were not necessarily intended to solve. Thus, for example, if a model is designed to describe a static magnetization curve, it should also be able to describe aspects of magnetization dynamics. Both micromagnetic modeling and Preisach modeling, the two most popular magnetic models, fulfill this requirement, but in the process of fulfilling this requirement, they both had to be modified in some ways. Hence, we should view physical modeling as an iterative process whereby we start with some simple assumptions and refine them as reality requires. In the process of refining these assumptions, we should try to appeal to physical arguments for the modifications, if we are to come up with good models. If we consider phenomenological models, on the other hand, that is as axiomatic models requiring no physical justification, we can follow them logically to see the end and examine the consequences of their assumptions. In this way, we can learn the properties, limitations and achievements of the particular model. Physical and phenomenological models complement each other in furthering our understanding of the behavior of magnetic materials

  12. Modelling Mathematical Reasoning in Physics Education

    Science.gov (United States)

    Uhden, Olaf; Karam, Ricardo; Pietrocola, Maurício; Pospiech, Gesche

    2012-04-01

    Many findings from research as well as reports from teachers describe students' problem solving strategies as manipulation of formulas by rote. The resulting dissatisfaction with quantitative physical textbook problems seems to influence the attitude towards the role of mathematics in physics education in general. Mathematics is often seen as a tool for calculation which hinders a conceptual understanding of physical principles. However, the role of mathematics cannot be reduced to this technical aspect. Hence, instead of putting mathematics away we delve into the nature of physical science to reveal the strong conceptual relationship between mathematics and physics. Moreover, we suggest that, for both prospective teaching and further research, a focus on deeply exploring such interdependency can significantly improve the understanding of physics. To provide a suitable basis, we develop a new model which can be used for analysing different levels of mathematical reasoning within physics. It is also a guideline for shifting the attention from technical to structural mathematical skills while teaching physics. We demonstrate its applicability for analysing physical-mathematical reasoning processes with an example.

  13. Understanding Leadership: An Experimental-Experiential Model

    Science.gov (United States)

    Hole, George T.

    2014-01-01

    Books about leadership are dangerous to readers who fantasize about being leaders or apply leadership ideas as if they were proven formulas. As an antidote, I offer an experimental framework in which any leadership-management model can be tested to gain experiential understanding of the model. As a result one can gain reality-based insights about…

  14. Using Models to Understand Sea Level Rise

    Science.gov (United States)

    Barth-Cohen, Lauren; Medina, Edwing

    2017-01-01

    Important science phenomena--such as atomic structure, evolution, and climate change--are often hard to observe directly. That's why an important scientific practice is to use scientific models to represent one's current understanding of a system. Using models has been included as an essential science and engineering practice in the "Next…

  15. Understanding catchment behaviour through model concept improvement

    NARCIS (Netherlands)

    Fenicia, F.

    2008-01-01

    This thesis describes an approach to model development based on the concept of iterative model improvement, which is a process where by trial and error different hypotheses of catchment behaviour are progressively tested, and the understanding of the system proceeds through a combined process of

  16. Thinking in physics the pleasure of reasoning and understanding

    CERN Document Server

    Viennot, Laurence

    2014-01-01

    Read this book if you care about students really understanding physics and getting genuine intellectual satisfaction from doing so. Read it too if you fear that this goal is out of reach ? you may be surprised! Laurence Viennot here shows ways to deal with the awkward fact that common sense thinking is often not the same as scientific thinking. She analyses examples of frequent and widespread errors and confusions, which provide a real eye-opener for the teacher. More than that, she shows ways to avoid and overcome them. The book argues against over-emphasis on "fun" applications, demonstratin

  17. Evolution in students' understanding of thermal physics with increasing complexity

    Science.gov (United States)

    Langbeheim, Elon; Safran, Samuel A.; Livne, Shelly; Yerushalmi, Edit

    2013-12-01

    We analyze the development in students’ understanding of fundamental principles in the context of learning a current interdisciplinary research topic—soft matter—that was adapted to the level of high school students. The topic was introduced in a program for interested 11th grade high school students majoring in chemistry and/or physics, in an off-school setting. Soft matter was presented in a gradual increase in the degree of complexity of the phenomena as well as in the level of the quantitative analysis. We describe the evolution in students’ use of fundamental thermodynamics principles to reason about phase separation—a phenomenon that is ubiquitous in soft matter. In particular, we examine the impact of the use of free energy analysis, a common approach in soft matter, on the understanding of the fundamental principles of thermodynamics. The study used diagnostic questions and classroom observations to gauge the student’s learning. In order to gain insight on the aspects that shape the understanding of the basic principles, we focus on the responses and explanations of two case-study students who represent two trends of evolution in conceptual understanding in the group. We analyze changes in the two case studies’ management of conceptual resources used in their analysis of phase separation, and suggest how their prior knowledge and epistemological framing (a combination of their personal tendencies and their prior exposure to different learning styles) affect their conceptual evolution. Finally, we propose strategies to improve the instruction of these concepts.

  18. Physical Modeling Modular Boxes: PHOXES

    DEFF Research Database (Denmark)

    Gelineck, Steven; Serafin, Stefania

    2010-01-01

    This paper presents the development of a set of musical instruments, which are based on known physical modeling sound synthesis techniques. The instruments are modular, meaning that they can be combined in various ways. This makes it possible to experiment with physical interaction and sonic...

  19. Standard Model physics

    CERN Multimedia

    Altarelli, Guido

    1999-01-01

    Introduction structure of gauge theories. The QEDand QCD examples. Chiral theories. The electroweak theory. Spontaneous symmetry breaking. The Higgs mechanism Gauge boson and fermion masses. Yukawa coupling. Charges current couplings. The Cabibo-Kobayashi-Maskawa matrix and CP violation. Neutral current couplings. The Glasow-Iliopoulos-Maiani mechanism. Gauge boson and Higgs coupling. Radiative corrections and loops. Cancellation of the chiral anomaly. Limits on the Higgs comparaison. Problems of the Standard Model. Outlook.

  20. BOOK REVIEW: New Understanding Physics for Advanced Level

    Science.gov (United States)

    Breithaupt, Jim

    2000-09-01

    Breithaupt's new book is big: at 727 pages, it will be a hefty addition to any student's bag. According to the preface, the book is designed to help students achieve the transition from GCSE to A-level and to succeed well at this level. It also aims to cover the requirements of the compulsory parts of all new syllabuses and to cover most of the optional material, too. The book is organized into seven themes along traditional lines: mechanics, materials, fields, waves, electricity, inside the atom, and physics in medicine. Each theme begins with a colourful title page that outlines what the theme is about, lists the applications that students will meet in their reading, identifies prior learning from GCSE and gives a checklist of what students should be able to do once they have finished their reading of the theme. This is all very useful. The text of the book is illustrated with many colourful photographs, pictures and cartoons, but despite this it looks very dense. There are a lot of words on every page in a small font that makes them seem very unfriendly, and although the book claims to be readable I rather doubt that the layout will encourage voluntary reading of the text. Each chapter ends with a useful summary and a selection of short questions that allow students to test their understanding. Each theme has a set of multiple choice and long questions. Some of the questions have an icon referring the student to the accompanying CD (more of this later). There is much up-to-date material in the book. For example, the section on cosmology gives a brief description of the inflationary scenario within the Big Bang model of the origin of the universe, although no mechanism for the inflation is given, which might prove unsatisfying to some students. I do have some reservations about the presentation of some topics within the book: the discussion of relativistic mass, for example, states that `Einstein showed that the mass ... is given by the formula ...' and quotes

  1. Understanding of QCD through solvable models

    Energy Technology Data Exchange (ETDEWEB)

    Bhattacharya, G.

    1980-07-01

    Various aspects of strong interaction physics are discussed. It is shown that several nontrivial features arise from non-perturbative 'solutions' of QCD-like models in (1+1) dimensions. An attempt is made to bring these features in (3+1) dimensional semiclassical treatments of QCD.

  2. Quasi standard model physics

    International Nuclear Information System (INIS)

    Peccei, R.D.

    1986-01-01

    Possible small extensions of the standard model are considered, which are motivated by the strong CP problem and by the baryon asymmetry of the Universe. Phenomenological arguments are given which suggest that imposing a PQ symmetry to solve the strong CP problem is only tenable if the scale of the PQ breakdown is much above M W . Furthermore, an attempt is made to connect the scale of the PQ breakdown to that of the breakdown of lepton number. It is argued that in these theories the same intermediate scale may be responsible for the baryon number of the Universe, provided the Kuzmin Rubakov Shaposhnikov (B+L) erasing mechanism is operative. (orig.)

  3. The Flipped Classroom and College Physics Students' Motivation and Understanding of Kinematics Graphs

    Science.gov (United States)

    Cagande, Jeffrey Lloyd L.; Jugar, Richard R.

    2018-01-01

    Reversing the traditional classroom activities, in the flipped classroom model students view lectures at home and perform activities during class period inside the classroom. This study investigated the effect of a flipped classroom implementation on college physics students' motivation and understanding of kinematics graphs. A Solomon four-group…

  4. Evolution in students’ understanding of thermal physics with increasing complexity

    Directory of Open Access Journals (Sweden)

    Elon Langbeheim

    2013-11-01

    Full Text Available We analyze the development in students’ understanding of fundamental principles in the context of learning a current interdisciplinary research topic—soft matter—that was adapted to the level of high school students. The topic was introduced in a program for interested 11th grade high school students majoring in chemistry and/or physics, in an off-school setting. Soft matter was presented in a gradual increase in the degree of complexity of the phenomena as well as in the level of the quantitative analysis. We describe the evolution in students’ use of fundamental thermodynamics principles to reason about phase separation—a phenomenon that is ubiquitous in soft matter. In particular, we examine the impact of the use of free energy analysis, a common approach in soft matter, on the understanding of the fundamental principles of thermodynamics. The study used diagnostic questions and classroom observations to gauge the student’s learning. In order to gain insight on the aspects that shape the understanding of the basic principles, we focus on the responses and explanations of two case-study students who represent two trends of evolution in conceptual understanding in the group. We analyze changes in the two case studies’ management of conceptual resources used in their analysis of phase separation, and suggest how their prior knowledge and epistemological framing (a combination of their personal tendencies and their prior exposure to different learning styles affect their conceptual evolution. Finally, we propose strategies to improve the instruction of these concepts.

  5. An exploration of university physics students’ epistemological mindsets towards the understanding of physics equations

    Directory of Open Access Journals (Sweden)

    Daniel Domert

    2012-07-01

    Full Text Available Students’ attitudes and beliefs about learning have been shown to affect learning outcomes. This study explores how university physics students think about what it means to understand physics equations. The data comes from semi-structured interviews with students from three Swedish universities. The analysis follows a data-based, inductive approach to characterise students’ descriptions of what it means to understand equations in terms of epistemological mindsets (perceived critical attributes of a learning, application, or problem-solving situation that are grounded in epistemology. The results are given in terms of different components of students’ epistemological mindsets. Relations between individuals and sets of components as well as differences across various stages of students’ academic career are then explored. Pedagogical implications of the findings are discussed and tentative suggestions for university physics teaching are made.

  6. Tales of the quantum understanding physics' most fundamental theory

    CERN Document Server

    Hobson, Art

    2017-01-01

    Everybody has heard that we live in a world made of atoms. But far more fundamentally, we live in a universe made of quanta. Many things are not made of atoms: light, radio waves, electric current, magnetic fields, Earth's gravitational field, not to mention exotica such a neutron stars, black holes, dark energy, and dark matter. But everything, including atoms, is made of highly unified or "coherent" bundles of energy called "quanta" that (like everything else) obey certain rules. In the case of the quantum, these rules are called "quantum physics." This is a book about quanta and their unexpected, some would say peculiar, behavior--tales, if you will, of the quantum. The quantum has developed the reputation of being capricious, bewildering, even impossible to understand. The peculiar habits of quanta are certainly not what we would have expected to find at the foundation of physical reality, but these habits are not necessarily bewildering and not at all impossible or paradoxical. This book explains those h...

  7. Understanding the physical properties of hybrid perovskites for photovoltaic applications

    Science.gov (United States)

    Huang, Jinsong; Yuan, Yongbo; Shao, Yuchuan; Yan, Yanfa

    2017-07-01

    New photovoltaic materials have been searched for in the past decades for clean and renewable solar energy conversion with an objective of reducing the levelized cost of electricity (that is, the unit price of electricity over the course of the device lifetime). An emerging family of semiconductor materials — organic-inorganic halide perovskites (OIHPs) — are the focus of the photovoltaic research community owing to their use of low cost, nature-abundant raw materials, low-temperature and scalable solution fabrication processes, and, in particular, the very high power conversion efficiencies that have been achieved within the short time of their development. In this Review, we summarize and critically assess the most recent advances in understanding the physical properties of both 3D and low-dimensional OIHPs that favour a small open-circuit voltage deficit and high power conversion efficiency. Several prominent topics in this field on the unique properties of OIHPs are surveyed, including defect physics, ferroelectricity, exciton dissociation processes, carrier recombination lifetime and photon recycling. The impact of ion migration on solar cell efficiency and stability are also critically analysed. Finally, we discuss the remaining challenges in the commercialization of OIHP photovoltaics.

  8. Understanding and modelling Man-Machine Interaction

    International Nuclear Information System (INIS)

    Cacciabue, P.C.

    1991-01-01

    This paper gives an overview of the current state of the art in man machine systems interaction studies, focusing on the problems derived from highly automated working environments and the role of humans in the control loop. In particular, it is argued that there is a need for sound approaches to design and analysis of Man-Machine Interaction (MMI), which stem from the contribution of three expertises in interfacing domains, namely engineering, computer science and psychology: engineering for understanding and modelling plants and their material and energy conservation principles; psychology for understanding and modelling humans and their cognitive behaviours; computer science for converting models in sound simulations running in appropriate computer architectures. (author)

  9. Understanding and modelling man-machine interaction

    International Nuclear Information System (INIS)

    Cacciabue, P.C.

    1996-01-01

    This paper gives an overview of the current state of the art in man-machine system interaction studies, focusing on the problems derived from highly automated working environments and the role of humans in the control loop. In particular, it is argued that there is a need for sound approaches to the design and analysis of man-machine interaction (MMI), which stem from the contribution of three expertises in interfacing domains, namely engineering, computer science and psychology: engineering for understanding and modelling plants and their material and energy conservation principles; psychology for understanding and modelling humans an their cognitive behaviours; computer science for converting models in sound simulations running in appropriate computer architectures. (orig.)

  10. Experimental electron density studies as key for understanding the chemical and physical properties in selected model systems; Experimentelle Elektronendichtestudien als Schluessel zum Verstaendnis chemischer und physikalischer Eigenschaften in ausgewaehlten Modellsystemen

    Energy Technology Data Exchange (ETDEWEB)

    Hauf, Christoph

    2014-12-17

    The topological analysis of experimentally determined electron density distributions, employing the quantum theory of atoms in molecules developed by Richard FW Bader, was used in this thesis to study chemically or physically motivated questions in appropriate model systems. First, transition metal complexes with activated C-H bonds or Si-H bonds were examined which led to a better understanding of agostic interactions. An important tool during these investigations is the so called atomic graph, which describes the characteristic spatial arrangement of the critical points of the Laplacefield of the electron density distribution in the valence shell of the relevant atoms. It reveals zones with a locally concentrated or depleted electron density distribution. This leads to the empirical rule, that a strong activation of C-H bonds or Si-H bonds is only observed when the hydrogen atom faces a pronounced charge depletion zone at the transition metal atom. In addition, the quasi one-dimensional rare-earth transition metal carbides Sc{sub 3}FeC{sub 4}, Sc{sub 3}CoC{sub 4} and Sc{sub 3}NiC{sub 4} were examined. Although all three compounds are isotypic at room temperature, it was revealed during this thesis, that only Sc{sub 3}CoC{sub 4} undergoes a structural phase transition at a temperature of ∝ 70 K and becomes superconducting below a critical temperature of 4.5 K. The main reason for this behaviour is the variation of the valence electrons through the exchange of Fe by Co or Ni. This results in the occupation of progressively higher energy electronic states and a raising of the Fermi level. The change in the nature of the electronic states at the Fermi level is in turn reflected by the different atomic graphs of the transition metal atoms and the distinct physical properties of these three compounds.

  11. Physical model of Nernst element

    International Nuclear Information System (INIS)

    Nakamura, Hiroaki; Ikeda, Kazuaki; Yamaguchi, Satarou

    1998-08-01

    Generation of electric power by the Nernst effect is a new application of a semiconductor. A key point of this proposal is to find materials with a high thermomagnetic figure-of-merit, which are called Nernst elements. In order to find candidates of the Nernst element, a physical model to describe its transport phenomena is needed. As the first model, we began with a parabolic two-band model in classical statistics. According to this model, we selected InSb as candidates of the Nernst element and measured their transport coefficients in magnetic fields up to 4 Tesla within a temperature region from 270 K to 330 K. In this region, we calculated transport coefficients numerically by our physical model. For InSb, experimental data are coincident with theoretical values in strong magnetic field. (author)

  12. Frameworks for understanding and describing business models

    DEFF Research Database (Denmark)

    Nielsen, Christian; Roslender, Robin

    2014-01-01

    This chapter provides in a chronological fashion an introduction to six frameworks that one can apply to describing, understanding and also potentially innovating business models. These six frameworks have been chosen carefully as they represent six very different perspectives on business models...... and in this manner “complement” each other. There are a multitude of varying frameworks that could be chosen from and we urge the reader to search and trial these for themselves. The six chosen models (year of release in parenthesis) are: • Service-Profit Chain (1994) • Strategic Systems Auditing (1997) • Strategy...... Maps (2001) • Intellectual Capital Statements (2003) • Chesbrough’s framework for Open Business Models (2006) • Business Model Canvas (2008)...

  13. Understanding space weather with new physical, mathematical and philosophical approaches

    Science.gov (United States)

    Mateev, Lachezar; Velinov, Peter; Tassev, Yordan

    2016-07-01

    The actual problems of solar-terrestrial physics, in particular of space weather are related to the prediction of the space environment state and are solved by means of different analyses and models. The development of these investigations can be considered also from another side. This is the philosophical and mathematical approach towards this physical reality. What does it constitute? We have a set of physical processes which occur in the Sun and interplanetary space. All these processes interact with each other and simultaneously participate in the general process which forms the space weather. Let us now consider the Leibniz's monads (G.W. von Leibniz, 1714, Monadologie, Wien; Id., 1710, Théodicée, Amsterdam) and use some of their properties. There are total 90 theses for monads in the Leibniz's work (1714), f.e. "(1) The Monad, of which we shall here speak, is nothing but a simple substance, which enters into compounds. By 'simple' is meant 'without parts'. (Theod. 10.); … (56) Now this connexion or adaptation of all created things to each and of each to all, means that each simple substance has relations which express all the others, and, consequently, that it is a perpetual living mirror of the universe. (Theod. 130, 360.); (59) … this universal harmony, according to which every substance exactly expresses all others through the relations it has with them. (63) … every Monad is, in its own way, a mirror of the universe, and the universe is ruled according to a perfect order. (Theod. 403.)", etc. Let us introduce in the properties of monads instead of the word "monad" the word "process". We obtain the following statement: Each process reflects all other processes and all other processes reflect this process. This analogy is not formal at all, it reflects accurately the relation between the physical processes and their unity. The category monad which in the Leibniz's Monadology reflects generally the philosophical sense is fully identical with the

  14. Instream Physical Habitat Modelling Types

    DEFF Research Database (Denmark)

    Conallin, John; Boegh, Eva; Krogsgaard, Jørgen

    2010-01-01

    The introduction of the EU Water Framework Directive (WFD) is providing member state water resource managers with significant challenges in relation to meeting the deadline for 'Good Ecological Status' by 2015. Overall, instream physical habitat modelling approaches have advantages and disadvanta......The introduction of the EU Water Framework Directive (WFD) is providing member state water resource managers with significant challenges in relation to meeting the deadline for 'Good Ecological Status' by 2015. Overall, instream physical habitat modelling approaches have advantages...... suit their situations. This paper analyses the potential of different methods available for water managers to assess hydrological and geomorphological impacts on the habitats of stream biota, as requested by the WFD. The review considers both conventional and new advanced research-based instream...... physical habitat models. In parametric and non-parametric regression models, model assumptions are often not satisfied and the models are difficult to transfer to other regions. Research-based methods such as the artificial neural networks and individual-based modelling have promising potential as water...

  15. Understanding Business Models in Health Care.

    Science.gov (United States)

    Sharan, Alok D; Schroeder, Gregory D; West, Michael E; Vaccaro, Alexander R

    2016-05-01

    The increasing focus on the costs of care is forcing health care organizations to critically look at their basic set of processes and activities, to determine what type of value they can deliver. A business model describes the resources, processes, and cost assumptions that an organization makes that will lead to the delivery of a unique value proposition to a customer. As health care organizations are beginning to transform their structure in preparation for a value-based delivery system, understanding business model theory can help in the redesign process.

  16. Centenarian offspring: a model for understanding longevity.

    Science.gov (United States)

    Balistreri, Carmela Rita; Candore, Giuseppina; Accardi, Giulia; Buffa, Silvio; Bulati, Matteo; Martorana, Adriana; Colonna-Romano, Giuseppina; Lio, Domenico; Caruso, Calogero

    2014-01-01

    A main objective of current medical research is to improve the life quality of elderly people as priority of the continuous increase of ageing population. This phenomenon implies several medical, economic and social problems because of dramatic increase in number of non autonomous individuals affected by various pathologies. Accordingly, the research interest is focused on understanding the biological mechanisms involved in determining the positive ageing phenotype, i.e. the centenarian phenotype. In achieving this goal the choice of an appropriate study models is fundamental. Centenarians have been used as an optimal model for successful ageing. However, this model shows several limitations, i.e. the selection of appropriate controls and the use itself of the centenarians as a suitable model for healthy ageing. Thus, the interest has been centered on centenarian offspring, healthy elderly people. They may represent a model for understanding exceptional longevity for the following reasons: they exhibit a protective genetic background, cardiovascular and immunological profile, as well as a reduced rate of cognitive decline than age-matched people without centenarian relatives. Several of these aspects are summarized in this review based on the literature and the results of our studies.

  17. Accelerator physics and modeling: Proceedings

    International Nuclear Information System (INIS)

    Parsa, Z.

    1991-01-01

    This report contains papers on the following topics: Physics of high brightness beams; radio frequency beam conditioner for fast-wave free-electron generators of coherent radiation; wake-field and space-charge effects on high brightness beams. Calculations and measured results for BNL-ATF; non-linear orbit theory and accelerator design; general problems of modeling for accelerators; development and application of dispersive soft ferrite models for time-domain simulation; and bunch lengthening in the SLC damping rings

  18. Wave Generation in Physical Models

    DEFF Research Database (Denmark)

    Andersen, Thomas Lykke; Frigaard, Peter

    The present book describes the most important aspects of wave generation techniques in physical models. Moreover, the book serves as technical documentation for the wave generation software AwaSys 6, cf. Aalborg University (2012). In addition to the two main authors also Tue Hald and Michael...

  19. Development of the physical model

    International Nuclear Information System (INIS)

    Liu Zunqi; Morsy, Samir

    2001-01-01

    Full text: The Physical Model was developed during Program 93+2 as a technical tool to aid enhanced information analysis and now is an integrated part of the Department's on-going State evaluation process. This paper will describe the concept of the Physical Model, including its objectives, overall structure and the development of indicators with designated strengths, followed by a brief description of using the Physical Model in implementing the enhanced information analysis. The work plan for expansion and update of the Physical Model is also presented at the end of the paper. The development of the Physical Model is an attempt to identify, describe and characterize every known process for carrying out each step necessary for the acquisition of weapons-usable material, i.e., all plausible acquisition paths for highly enriched uranium (HEU) and separated plutonium (Pu). The overall structure of the Physical Model has a multilevel arrangement. It includes at the top level all the main steps (technologies) that may be involved in the nuclear fuel cycle from the source material production up to the acquisition of weapons-usable material, and then beyond the civilian fuel cycle to the development of nuclear explosive devices (weaponization). Each step is logically interconnected with the preceding and/or succeeding steps by nuclear material flows. It contains at its lower levels every known process that is associated with the fuel cycle activities presented at the top level. For example, uranium enrichment is broken down into three branches at the second level, i.e., enrichment of UF 6 , UCl 4 and U-metal respectively; and then further broken down at the third level into nine processes: gaseous diffusion, gas centrifuge, aerodynamic, electromagnetic, molecular laser (MLIS), atomic vapor laser (AVLIS), chemical exchange, ion exchange and plasma. Narratives are presented at each level, beginning with a general process description then proceeding with detailed

  20. Mediating Relationship of Differential Products in Understanding Integration in Introductory Physics

    Science.gov (United States)

    Amos, Nathaniel; Heckler, Andrew F.

    2018-01-01

    In the context of introductory physics, we study student conceptual understanding of differentials, differential products, and integrals and possible pathways to understanding these quantities. We developed a multiple choice conceptual assessment employing a variety of physical contexts probing physical understanding of these three quantities and…

  1. Pre-Service Physics Teachers' Understanding of the Relational Structure of Physics Concepts: Organising Subject Contents for Purposes of Teaching

    Science.gov (United States)

    Koponen, Ismo; Nousiainen, Maija

    2013-01-01

    Good conceptual understanding of physics is based on understanding what the key concepts are and how they are related. This kind of understanding is especially important for physics teachers in planning how and in what order to introduce concepts in teaching; connections which tie concepts to each other give direction of progress--there is "flux…

  2. Effectiveness of Ninth-Grade Physics in Maine: Conceptual Understanding

    OpenAIRE

    O'Brien, Michael; Thompson, John

    2009-01-01

    The Physics First movement - teaching a true physics course to ninth grade students - is gaining popularity in high schools. There are several different rhetorical arguments for and against this movement, and it is quite controversial in physics education. However, there is no actual evidence to assess the success, or failure, of this substantial shift in the science teaching sequence. We have undertaken a comparison study of physics classes taught in ninth- and 12th grade classes in Maine. C...

  3. Correlation of understanding of physics and psychological symptoms among high-school students in Greece

    Science.gov (United States)

    Aggeliki, Anagnostopoulou; Miltiades, Kyprianou; Antigoni-Elisavet, Rota; Evangelia, Pavlatou; Loizos, Zaphiris

    2017-09-01

    Depression may essentially influence cognitive function contributing to poor school performance. The present study undertakes to determine the existence and strength of correlation between depressive symptomatology and other mental conditions with the acquired level of understanding of Newtonian physics taught in schools. The current study recruited 490 students (262 girls, 228 boys) attending the first semester of the Greek Second Grade of General Lyceum School. Force Concept Inventory (FCI) tested the depth of the students’ understanding of Newtonian Physics. Symptom Checklist-90-R assessed general mental status. The tests took place in the classroom during a 1 h session. Low FCI scores significantly correlated with mental conditions, with depression ranking first. Girls had higher scores in all nine symptoms scales of SCL-90 and lower FCI scores. Stepwise regression models proved that the gender effect on FCI could be effectively explained through the significant effect of depression. An understanding of Newtonian physics among high school students may be restricted by common problematic mental conditions, with depression being the greatest among all. Further research, using a more systematic approach to measure depression among adolescents with poor understanding of physics, would help to elucidate the nature of the effect.

  4. Understanding Solar Coronal Heating through Atomic and Plasma Physics Experiments

    Science.gov (United States)

    Savin, Daniel Wolf; Arthanayaka, Thusitha; Bose, Sayak; Hahn, Michael; Beiersdorfer, Peter; Brown, Gregory V.; Gekelman, Walter; Vincena, Steve

    2017-08-01

    Recent solar observations suggest that the Sun's corona is heated by Alfven waves that dissipate at unexpectedly low heights in the corona. These observations raise a number of questions. Among them are the problems of accurately quantifying the energy flux of the waves and that of describing the physical mechanism that leads to the wave damping. We are performing laboratory experiments to address both of these issues.The energy flux depends on the electron density, which can be measured spectroscopically. However, spectroscopic density diagnostics have large uncertainties, because they depend sensitively on atomic collisional excitation, de-excitation, and radiative transition rates for multiple atomic levels. Essentially all of these data come from theory and have not been experimentally validated. We are conducting laboratory experiments using the electron beam ion trap (EBIT) at Lawrence Livermore National Laboratory that will provide accurate empirical calibrations for spectroscopic density diagnostics and which will also help to guide theoretical calculations.The observed rapid wave dissipation is likely due to inhomogeneities in the plasma that drive flows and currents at small length scales where energy can be more efficiently dissipated. This may take place through gradients in the Alfvén speed along the magnetic field, which causes wave reflection and generates turbulence. Alternatively, gradients in the Alfvén speed across the field can lead to dissipation through phase-mixing. Using the Large Plasma Device (LAPD) at the University of California Los Angeles, we are studying both of these dissipation mechanisms in the laboratory in order to understand their potential roles in coronal heating.

  5. Physical model of reactor pulse

    International Nuclear Information System (INIS)

    Petrovic, A.; Ravnik, M.

    2004-01-01

    Pulse experiments have been performed at J. Stefan Institute TRIGA reactor since 1991. In total, more than 130 pulses have been performed. Extensive experimental information on the pulse physical characteristics has been accumulated. Fuchs-Hansen adiabatic model has been used for predicting and analysing the pulse parameters. The model is based on point kinetics equation, neglecting the delayed neutrons and assuming constant inserted reactivity in form of step function. Deficiencies of the Fuchs-Hansen model and systematic experimental errors have been observed and analysed. Recently, the pulse model was improved by including the delayed neutrons and time dependence of inserted reactivity. The results explain the observed non-linearity of the pulse energy for high pulses due to finite time of pulse rod withdrawal and the contribution of the delayed neutrons after the prompt part of the pulse. The results of the improved model are in good agreement with experimental results. (author)

  6. Mechanistic movement models to understand epidemic spread.

    Science.gov (United States)

    Fofana, Abdou Moutalab; Hurford, Amy

    2017-05-05

    An overlooked aspect of disease ecology is considering how and why animals come into contact with one and other resulting in disease transmission. Mathematical models of disease spread frequently assume mass-action transmission, justified by stating that susceptible and infectious hosts mix readily, and foregoing any detailed description of host movement. Numerous recent studies have recorded, analysed and modelled animal movement. These movement models describe how animals move with respect to resources, conspecifics and previous movement directions and have been used to understand the conditions for the occurrence and the spread of infectious diseases when hosts perform a type of movement. Here, we summarize the effect of the different types of movement on the threshold conditions for disease spread. We identify gaps in the literature and suggest several promising directions for future research. The mechanistic inclusion of movement in epidemic models may be beneficial for the following two reasons. Firstly, the estimation of the transmission coefficient in an epidemic model is possible because animal movement data can be used to estimate the rate of contacts between conspecifics. Secondly, unsuccessful transmission events, where a susceptible host contacts an infectious host but does not become infected can be quantified. Following an outbreak, this enables disease ecologists to identify 'near misses' and to explore possible alternative epidemic outcomes given shifts in ecological or immunological parameters.This article is part of the themed issue 'Opening the black box: re-examining the ecology and evolution of parasite transmission'. © 2017 The Author(s).

  7. Understanding National Models for Climate Assessments

    Science.gov (United States)

    Dave, A.; Weingartner, K.

    2017-12-01

    National-level climate assessments have been produced or are underway in a number of countries. These efforts showcase a variety of approaches to mapping climate impacts onto human and natural systems, and involve a variety of development processes, organizational structures, and intended purposes. This presentation will provide a comparative overview of national `models' for climate assessments worldwide, drawing from a geographically diverse group of nations with varying capacities to conduct such assessments. Using an illustrative sampling of assessment models, the presentation will highlight the range of assessment mandates and requirements that drive this work, methodologies employed, focal areas, and the degree to which international dimensions are included for each nation's assessment. This not only allows the U.S. National Climate Assessment to be better understood within an international context, but provides the user with an entry point into other national climate assessments around the world, enabling a better understanding of the risks and vulnerabilities societies face.

  8. Physical models for classroom teaching in hydrology

    Directory of Open Access Journals (Sweden)

    A. Rodhe

    2012-09-01

    Full Text Available Hydrology teaching benefits from the fact that many important processes can be illustrated and explained with simple physical models. A set of mobile physical models has been developed and used during many years of lecturing at basic university level teaching in hydrology. One model, with which many phenomena can be demonstrated, consists of a 1.0-m-long plexiglass container containing an about 0.25-m-deep open sand aquifer through which water is circulated. The model can be used for showing the groundwater table and its influence on the water content in the unsaturated zone and for quantitative determination of hydraulic properties such as the storage coefficient and the saturated hydraulic conductivity. It is also well suited for discussions on the runoff process and the significance of recharge and discharge areas for groundwater. The flow paths of water and contaminant dispersion can be illustrated in tracer experiments using fluorescent or colour dye. This and a few other physical models, with suggested demonstrations and experiments, are described in this article. The finding from using models in classroom teaching is that it creates curiosity among the students, promotes discussions and most likely deepens the understanding of the basic processes.

  9. Understanding and Modeling Teams As Dynamical Systems

    Science.gov (United States)

    Gorman, Jamie C.; Dunbar, Terri A.; Grimm, David; Gipson, Christina L.

    2017-01-01

    By its very nature, much of teamwork is distributed across, and not stored within, interdependent people working toward a common goal. In this light, we advocate a systems perspective on teamwork that is based on general coordination principles that are not limited to cognitive, motor, and physiological levels of explanation within the individual. In this article, we present a framework for understanding and modeling teams as dynamical systems and review our empirical findings on teams as dynamical systems. We proceed by (a) considering the question of why study teams as dynamical systems, (b) considering the meaning of dynamical systems concepts (attractors; perturbation; synchronization; fractals) in the context of teams, (c) describe empirical studies of team coordination dynamics at the perceptual-motor, cognitive-behavioral, and cognitive-neurophysiological levels of analysis, and (d) consider the theoretical and practical implications of this approach, including new kinds of explanations of human performance and real-time analysis and performance modeling. Throughout our discussion of the topics we consider how to describe teamwork using equations and/or modeling techniques that describe the dynamics. Finally, we consider what dynamical equations and models do and do not tell us about human performance in teams and suggest future research directions in this area. PMID:28744231

  10. Animal and human models to understand ageing.

    Science.gov (United States)

    Lees, Hayley; Walters, Hannah; Cox, Lynne S

    2016-11-01

    Human ageing is the gradual decline in organ and tissue function with increasing chronological time, leading eventually to loss of function and death. To study the processes involved over research-relevant timescales requires the use of accessible model systems that share significant similarities with humans. In this review, we assess the usefulness of various models, including unicellular yeasts, invertebrate worms and flies, mice and primates including humans, and highlight the benefits and possible drawbacks of each model system in its ability to illuminate human ageing mechanisms. We describe the strong evolutionary conservation of molecular pathways that govern cell responses to extracellular and intracellular signals and which are strongly implicated in ageing. Such pathways centre around insulin-like growth factor signalling and integration of stress and nutritional signals through mTOR kinase. The process of cellular senescence is evaluated as a possible underlying cause for many of the frailties and diseases of human ageing. Also considered is ageing arising from systemic changes that cannot be modelled in lower organisms and instead require studies either in small mammals or in primates. We also touch briefly on novel therapeutic options arising from a better understanding of the biology of ageing. Copyright © 2016. Published by Elsevier Ireland Ltd.

  11. Problematizing a general physics class: Understanding student engagement

    Science.gov (United States)

    Spaid, Mark Randall

    This research paper describes the problems in democratizing a high school physics course and the disparate engagement students during class activities that promote scientific inquiry. Results from the Learning Orientation Questionnaire (Martinez, 2000) guide the participant observations and semi-formal interviews. Approximately 60% of the participants self-report a "resistant" or "conforming" approach to learning science; they expect to receive science knowledge from the teacher, and their engagement is influenced by affective and conative factors. These surface learners exhibit second order thinking (Kegan, 1994), do not understand abstract science concepts, and learn best from structured inquiry. To sustain engagement, conforming learners require motivational and instructional discourse from their teacher and peers. Resisting learners do not value learning and do not engage in most science class activities. The "performing" learners are able to deal with abstractions and can see relationships between lessons and activities, but they do not usually self-reflect or think critically (they are between Kegan's second order and third order thinking). They may select a deeper learning strategy if they value the knowledge for a future goal; however, they are oriented toward assessment and rely on the science teacher as an authority. They are influenced by affective and conative factors during structured and guided inquiry-based teaching, and benefit from motivational discourse and sustain engagement if they are interested in the topic. The transforming learners are more independent, self-assessing and self-directed. These students are third order thinkers (Kegan, 1994) who hold a sophisticated epistemology that includes critical thinking and reflection. These students select deep learning strategies without regard to affective and conative factors. They value instructional discourse from the teacher, but prefer less structured inquiry activities. Although specific

  12. A new model for understanding the public

    International Nuclear Information System (INIS)

    Bisconti, A.S.

    1995-01-01

    Progress in siting waste facilities has been impeded by a too-limited understanding of what the public wants. National and statewide surveys sponsored by the U.S. Council for Energy Awareness and others on both high-level and low-level radioactive waste reveal a new, more comprehensive model for assessing public opinion. These surveys by independent research firms -- Market Strategies, Gordon S. Black, Tarrance, and Bruskin/Goldring -- have a margin of error of +3% for national polls and +4% for statewide polls. The old model assumes that because people fear radioactive waste, support for building waste facilities is politically risky. The new model shows that fear of radioactive waste is an important dynamic, but reaches a different conclusion about the public's sense of generational responsibility. Because people see waste as dangerous, most support the principle of transporting the waste to a permanent disposal facility instead of keeping the waste stored at many different sites. Most want to keep the uses of radioactive materials that produce waste -- including nuclear energy. They strongly believe that disposing of radioactive waste now instead of leaving it for future generations is the environmentally responsible thing to do

  13. Understanding the Importance, Dimensions and Settings for Developing Children’s Physical Activity Behaviour

    OpenAIRE

    Hyndman, Brendon

    2015-01-01

    Promotion of regular physical activity during childhood within schools, home and community settings is important as childhood forms the foundation for physical activity habits that can track into adulthood. Despite childhood being a crucial period for developing physical activity behaviour, there is a limited understanding of the physical activity behaviours of school-aged children. The aim of this research report is to facilitate understanding of children’s physical activity behaviours by ou...

  14. Physical Model Method for Seismic Study of Concrete Dams

    Directory of Open Access Journals (Sweden)

    Bogdan Roşca

    2008-01-01

    Full Text Available The study of the dynamic behaviour of concrete dams by means of the physical model method is very useful to understand the failure mechanism of these structures to action of the strong earthquakes. Physical model method consists in two main processes. Firstly, a study model must be designed by a physical modeling process using the dynamic modeling theory. The result is a equations system of dimensioning the physical model. After the construction and instrumentation of the scale physical model a structural analysis based on experimental means is performed. The experimental results are gathered and are available to be analysed. Depending on the aim of the research may be designed an elastic or a failure physical model. The requirements for the elastic model construction are easier to accomplish in contrast with those required for a failure model, but the obtained results provide narrow information. In order to study the behaviour of concrete dams to strong seismic action is required the employment of failure physical models able to simulate accurately the possible opening of joint, sliding between concrete blocks and the cracking of concrete. The design relations for both elastic and failure physical models are based on dimensional analysis and consist of similitude relations among the physical quantities involved in the phenomenon. The using of physical models of great or medium dimensions as well as its instrumentation creates great advantages, but this operation involves a large amount of financial, logistic and time resources.

  15. Towards The Deep Model : Understanding Visual Recognition Through Computational Models

    OpenAIRE

    Wang, Panqu

    2017-01-01

    Understanding how visual recognition is achieved in the human brain is one of the most fundamental questions in vision research. In this thesis I seek to tackle this problem from a neurocomputational modeling perspective. More specifically, I build machine learning-based models to simulate and explain cognitive phenomena related to human visual recognition, and I improve computational models using brain-inspired principles to excel at computer vision tasks.I first describe how a neurocomputat...

  16. Physics understanding the properties of matter and energy

    CERN Document Server

    2015-01-01

    Without physics, modern life would not exist. Instead of electric light, we would read by the light of candles. We couldn''t build skyscrapers. We could not possibly bridge rivers, much less build a jet or interplanetary craft. Computers and smartphones would be unimaginable. Physics is concerned with the most fundamental aspects of matter and energy and how they interact to make the physical universe work. In accessible language and with explanatory graphics and visual aids, this book introduces readers to the science that is at the very center of all other sciences and essential to our very

  17. Cabin Environment Physics Risk Model

    Science.gov (United States)

    Mattenberger, Christopher J.; Mathias, Donovan Leigh

    2014-01-01

    This paper presents a Cabin Environment Physics Risk (CEPR) model that predicts the time for an initial failure of Environmental Control and Life Support System (ECLSS) functionality to propagate into a hazardous environment and trigger a loss-of-crew (LOC) event. This physics-of failure model allows a probabilistic risk assessment of a crewed spacecraft to account for the cabin environment, which can serve as a buffer to protect the crew during an abort from orbit and ultimately enable a safe return. The results of the CEPR model replace the assumption that failure of the crew critical ECLSS functionality causes LOC instantly, and provide a more accurate representation of the spacecraft's risk posture. The instant-LOC assumption is shown to be excessively conservative and, moreover, can impact the relative risk drivers identified for the spacecraft. This, in turn, could lead the design team to allocate mass for equipment to reduce overly conservative risk estimates in a suboptimal configuration, which inherently increases the overall risk to the crew. For example, available mass could be poorly used to add redundant ECLSS components that have a negligible benefit but appear to make the vehicle safer due to poor assumptions about the propagation time of ECLSS failures.

  18. Determining which introductory physics topics pre-service physics teachers have difficulty understanding and what accounts for these difficulties

    International Nuclear Information System (INIS)

    Şahin, Esin; Yağbasan, Rahmi

    2012-01-01

    This study aims at diagnosing which subjects pre-service physics teachers have difficulty understanding in introductory physics courses and what accounts for these difficulties. A questionnaire consisting of two qualitative questions was used to collect data for this study. The questionnaire was administered to 101 pre-service physics teachers who have completed the courses Physics 1 (Mechanics 1), Physics 2 (Mechanics 2), Physics 3 (Electricity) and Physics 4 (Magnetism). Of the pre-service physics teachers 28 were second year, 26 were third year, 27 were fourth year and 20 were fifth year students. The results of the data analysis indicated that the percentage of students who think that Magnetism has the most difficult subjects is the highest compared to the others. The reasons why the pre-service physics teachers experience difficulty in understanding the subjects have been grouped into four categories. (paper)

  19. A Multivariate Model of Physics Problem Solving

    Science.gov (United States)

    Taasoobshirazi, Gita; Farley, John

    2013-01-01

    A model of expertise in physics problem solving was tested on undergraduate science, physics, and engineering majors enrolled in an introductory-level physics course. Structural equation modeling was used to test hypothesized relationships among variables linked to expertise in physics problem solving including motivation, metacognitive planning,…

  20. Evaluating College Students' Conceptual Knowledge of Modern Physics: Test of Understanding on Concepts of Modern Physics (TUCO-MP)

    Science.gov (United States)

    Akarsu, Bayram

    2011-01-01

    In present paper, we propose a new diagnostic test to measure students' conceptual knowledge of principles of modern physics topics. Over few decades since born of physics education research (PER), many diagnostic instruments that measure students' conceptual understanding of various topics in physics, the earliest tests developed in PER are Force…

  1. Determining Which Introductory Physics Topics Pre-Service Physics Teachers Have Difficulty Understanding and What Accounts for These Difficulties

    Science.gov (United States)

    Sahin, Esin; Yagbasan, Rahmi

    2012-01-01

    This study aims at diagnosing which subjects pre-service physics teachers have difficulty understanding in introductory physics courses and what accounts for these difficulties. A questionnaire consisting of two qualitative questions was used to collect data for this study. The questionnaire was administered to 101 pre-service physics teachers who…

  2. Models and structures: mathematical physics

    International Nuclear Information System (INIS)

    2003-01-01

    This document gathers research activities along 5 main directions. 1) Quantum chaos and dynamical systems. Recent results concern the extension of the exact WKB method that has led to a host of new results on the spectrum and wave functions. Progress have also been made in the description of the wave functions of chaotic quantum systems. Renormalization has been applied to the analysis of dynamical systems. 2) Combinatorial statistical physics. We see the emergence of new techniques applied to various such combinatorial problems, from random walks to random lattices. 3) Integrability: from structures to applications. Techniques of conformal field theory and integrable model systems have been developed. Progress is still made in particular for open systems with boundary conditions, in connection to strings and branes physics. Noticeable links between integrability and exact WKB quantization to 2-dimensional disordered systems have been highlighted. New correlations of eigenvalues and better connections to integrability have been formulated for random matrices. 4) Gravities and string theories. We have developed aspects of 2-dimensional string theory with a particular emphasis on its connection to matrix models as well as non-perturbative properties of M-theory. We have also followed an alternative path known as loop quantum gravity. 5) Quantum field theory. The results obtained lately concern its foundations, in flat or curved spaces, but also applications to second-order phase transitions in statistical systems

  3. The Role of Nuclear Physics in Understanding the Cosmos and the Origin of Elements

    International Nuclear Information System (INIS)

    Balantekin, A. B.

    2011-01-01

    This popular lecture, given in the conference celebrating contributions of Akito Arima to physics on the occasion of his 80th anniversary, outlines the role of nuclear physics in understanding the origin of elements.

  4. Teaching and Understanding of Quantum Interpretations in Modern Physics Courses

    Science.gov (United States)

    Baily, Charles; Finkelstein, Noah D.

    2010-01-01

    Just as expert physicists vary in their personal stances on interpretation in quantum mechanics, instructors vary on whether and how to teach interpretations of quantum phenomena in introductory modern physics courses. In this paper, we document variations in instructional approaches with respect to interpretation in two similar modern physics…

  5. Kinetic physics in ICF: present understanding and future directions

    Science.gov (United States)

    Rinderknecht, Hans G.; Amendt, P. A.; Wilks, S. C.; Collins, G.

    2018-06-01

    Kinetic physics has the potential to impact the performance of indirect-drive inertial confinement fusion (ICF) experiments. Systematic anomalies in the National Ignition Facility implosion dataset have been identified in which kinetic physics may play a role, including inferred missing energy in the hohlraum, drive asymmetry in near-vacuum hohlraums, low areal density and high burn-averaged ion temperatures (〈Ti 〉) compared with mainline simulations, and low ratios of the DD-neutron and DT-neutron yields and inferred 〈Ti 〉. Several components of ICF implosions are likely to be influenced or dominated by kinetic physics: laser-plasma interactions in the LEH and hohlraum interior; the hohlraum wall blowoff, blowoff/gas and blowoff/ablator interfaces; the ablator and ablator/ice interface; and the DT fuel all present conditions in which kinetic physics can significantly affect the dynamics. This review presents the assembled experimental data and simulation results to date, which indicate that the effects of long mean-free-path plasma phenomena and self-generated electromagnetic fields may have a significant impact in ICF targets. Simulation and experimental efforts are proposed to definitively quantify the importance of these effects at ignition-relevant conditions, including priorities for ongoing study.

  6. Designing for Enhanced Conceptual Understanding in an Online Physics Course

    Science.gov (United States)

    Dunlap, Joanna C.; Furtak, Thomas E.; Tucker, Susan A.

    2009-01-01

    The calculus-based, introductory physics course is the port of entry for any student interested in pursuing a college degree in the sciences, mathematics, or engineering. There is increasing demand for online delivery options that make the course more widely available, especially those that use best practices in student engagement. However,…

  7. Science Understanding through Playground Physics: Organized Recess Teaching (SUPPORT)

    Science.gov (United States)

    Kincaid, Russell

    2010-03-01

    From 1995-2007, U.S. science students in grade four scored higher than the scaled TIMSS average, but their scores did not improve over this time. Moreover, in the area of physical science, the U.S. scored significantly lower than several Asian countries, as well as Russia, England, and Latvia (TIMSS). Methods to enhance student achievement in science are still being sought. An approach to utilizing playground equipment as a teaching tool for a variety of physics concepts was developed as a physical science teaching method. This program established an appropriate set of experiments, coordinated the effort with local school districts, and implemented a brief pilot study to test the teaching methodology. The program assigned undergraduate middle school science education majors to teach small groups of fourth grade students. The experimental group used the newly developed ``Playground Physics'' methodology while the control group used traditional approaches. Follow up activities will include an expansion of the duration and the scope of the program.

  8. Discontinuities in Early Development of the Understanding of Physical Causality

    Science.gov (United States)

    Aschersleben, Gisa; Henning, Anne; Daum, Moritz M.

    2013-01-01

    Research on early physical reasoning has shown surprising discontinuities in developmental trajectories. Infants possess some skills that seem to disappear and then re-emerge in childhood. It has been suggested that prediction skills required in search tasks might cause these discontinuities (Keen, 2003). We tested 3.5- to 5-year-olds'…

  9. Model for understanding consumer textural food choice.

    Science.gov (United States)

    Jeltema, Melissa; Beckley, Jacqueline; Vahalik, Jennifer

    2015-05-01

    The current paradigm for developing products that will match the marketing messaging is flawed because the drivers of product choice and satisfaction based on texture are misunderstood. Qualitative research across 10 years has led to the thesis explored in this research that individuals have a preferred way to manipulate food in their mouths (i.e., mouth behavior) and that this behavior is a major driver of food choice, satisfaction, and the desire to repurchase. Texture, which is currently thought to be a major driver of product choice, is a secondary factor, and is important only in that it supports the primary driver-mouth behavior. A model for mouth behavior is proposed and the qualitative research supporting the identification of different mouth behaviors is presented. The development of a trademarked typing tool for characterizing mouth behavior is described along with quantitative substantiation of the tool's ability to group individuals by mouth behavior. The use of these four groups to understand textural preferences and the implications for a variety of areas including product design and weight management are explored.

  10. Manipulating 3D-Printed and Paper Models Enhances Student Understanding of Viral Replication

    Science.gov (United States)

    Couper, Lisa; Johannes, Kristen; Powers, Jackie; Silberglitt, Matt; Davenport, Jodi

    2016-01-01

    Understanding key concepts in molecular biology requires reasoning about molecular processes that are not directly observable and, as such, presents a challenge to students and teachers. We ask whether novel interactive physical models and activities can help students understand key processes in viral replication. Our 3D tangible models are…

  11. LHC Higgs physics beyond the Standard Model

    International Nuclear Information System (INIS)

    Spannowsky, M.

    2007-01-01

    The Large Hadron Collider (LHC) at CERN will be able to perform proton collisions at a much higher center-of-mass energy and luminosity than any other collider. Its main purpose is to detect the Higgs boson, the last unobserved particle of the Standard Model, explaining the riddle of the origin of mass. Studies have shown, that for the whole allowed region of the Higgs mass processes exist to detect the Higgs at the LHC. However, the Standard Model cannot be a theory of everything and is not able to provide a complete understanding of physics. It is at most an effective theory up to a presently unknown energy scale. Hence, extensions of the Standard Model are necessary which can affect the Higgs-boson signals. We discuss these effects in two popular extensions of the Standard Model: the Minimal Supersymmetric Standard Model (MSSM) and the Standard Model with four generations (SM4G). Constraints on these models come predominantly from flavor physics and electroweak precision measurements. We show, that the SM4G is still viable and that a fourth generation has strong impact on decay and production processes of the Higgs boson. Furthermore, we study the charged Higgs boson in the MSSM, yielding a clear signal for physics beyond the Standard Model. For small tan β in minimal flavor violation (MFV) no processes for the detection of a charged Higgs boson do exist at the LHC. However, MFV is just motivated by the experimental agreement of results from flavor physics with Standard Model predictions, but not by any basic theoretical consideration. In this thesis, we calculate charged Higgs boson production cross sections beyond the assumption of MFV, where a large number of free parameters is present in the MSSM. We find that the soft-breaking parameters which enhance the charged-Higgs boson production most are just bound to large values, e.g. by rare B-meson decays. Although the charged-Higgs boson cross sections beyond MFV turn out to be sizeable, only a detailed

  12. LHC Higgs physics beyond the Standard Model

    Energy Technology Data Exchange (ETDEWEB)

    Spannowsky, M.

    2007-09-22

    The Large Hadron Collider (LHC) at CERN will be able to perform proton collisions at a much higher center-of-mass energy and luminosity than any other collider. Its main purpose is to detect the Higgs boson, the last unobserved particle of the Standard Model, explaining the riddle of the origin of mass. Studies have shown, that for the whole allowed region of the Higgs mass processes exist to detect the Higgs at the LHC. However, the Standard Model cannot be a theory of everything and is not able to provide a complete understanding of physics. It is at most an effective theory up to a presently unknown energy scale. Hence, extensions of the Standard Model are necessary which can affect the Higgs-boson signals. We discuss these effects in two popular extensions of the Standard Model: the Minimal Supersymmetric Standard Model (MSSM) and the Standard Model with four generations (SM4G). Constraints on these models come predominantly from flavor physics and electroweak precision measurements. We show, that the SM4G is still viable and that a fourth generation has strong impact on decay and production processes of the Higgs boson. Furthermore, we study the charged Higgs boson in the MSSM, yielding a clear signal for physics beyond the Standard Model. For small tan {beta} in minimal flavor violation (MFV) no processes for the detection of a charged Higgs boson do exist at the LHC. However, MFV is just motivated by the experimental agreement of results from flavor physics with Standard Model predictions, but not by any basic theoretical consideration. In this thesis, we calculate charged Higgs boson production cross sections beyond the assumption of MFV, where a large number of free parameters is present in the MSSM. We find that the soft-breaking parameters which enhance the charged-Higgs boson production most are just bound to large values, e.g. by rare B-meson decays. Although the charged-Higgs boson cross sections beyond MFV turn out to be sizeable, only a detailed

  13. Framework for Understanding LENR Processes, Using Ordinary Condensed Matter Physics

    Science.gov (United States)

    Chubb, Scott

    2005-03-01

    As I have emphasizedootnotetextS.R. Chubb, Proc. ICCF10 (in press). Also, http://www.lenr-canr.org/acrobat/ChubbSRnutsandbol.pdf http://www.lenr-canr.org/acrobat/ChubbSRnutsandbol.pdf, S.R. Chubb, Trans. Amer. Nuc. Soc. 88 , 618 (2003)., in discussions of Low Energy Nuclear Reactions(LENRs), mainstream many-body physics ideas have been largely ignored. A key point is that in condensed matter, delocalized, wave-like effects can allow large amounts of momentum to be transferred instantly to distant locations, without any particular particle (or particles) acquiring high velocity through a Broken Gauge Symmetry. Explicit features in the electronic structure explain how this can occur^1 in finite size PdD crystals, with real boundaries. The essential physics^1 can be related to standard many-body techniquesootnotetextBurke,P.G. and K.A. Berrington, Atomic and Molecular Processes:an R matrix Approach (Bristol: IOP Publishing, 1993).. In the paper, I examine this relationship, the relationship of the theory^1 to other LENR theories, and the importance of certain features (for example, boundaries^1) that are not included in the other LENR theories.

  14. Using the self-determination theory to understand Chinese adolescent leisure-time physical activity.

    Science.gov (United States)

    Wang, Lijuan

    2017-05-01

    This study applies the self-determination theory (SDT) to test the hypothesized relationships among perceived autonomy support from parents, physical education (PE) teachers, and peers, the fulfilment of psychological needs (i.e., autonomy, competence, and relatedness), autonomous motivation, and leisure-time physical activity of Chinese adolescents. There are 255 grade six to eight student participants from four middle schools around Shanghai, China included in this study. An accelerometer was used to measure the moderate-to-vigorous physical activity (MVPA). The participants completed the questionnaires regarding SDT variables. The structural equation modelling was applied to examine the hypothesized relationships among the study variables. The model of hypothesized relationships demonstrated a good fit with the data [X 2  = 20.84, df = 9, P = .01; CFI = 0.98; IFI = 0.98; SRMR = 0.04; RMSEA = 0.05]. The findings revealed that autonomy support from parents, PE teachers, and peers foster social conditions in which the three basic psychological needs can be met. In turn, autonomy, competence, and relatedness are positively associated with autonomous motivation for MVPA. The autonomous motivation positively relates to the MVPA time of adolescents. The three psychological needs partially mediate the influence of autonomy support from parents (β = 0.18, P motivation. In conclusion, these findings support the applicability of SDT in understanding and promoting physical activity of Chinese adolescents.

  15. Pre-Service Physics Teachers' Opinions about the Difficulties in Understanding Introductory Quantum Physics Topics

    Science.gov (United States)

    Kizilcik, Hasan Sahin; Yavas, Pervin Ünlü

    2017-01-01

    The aim of this study is to identify the opinions of pre-service physics teachers about the difficulties in introductory quantum physics topics. In this study conducted with twenty-five pre-service physics teachers, the case study method was used. The participants were interviewed about introductory quantum physics topics. The interviews were…

  16. Simulation-Based Performance Assessment: An Innovative Approach to Exploring Understanding of Physical Science Concepts

    Science.gov (United States)

    Gale, Jessica; Wind, Stefanie; Koval, Jayma; Dagosta, Joseph; Ryan, Mike; Usselman, Marion

    2016-01-01

    This paper illustrates the use of simulation-based performance assessment (PA) methodology in a recent study of eighth-grade students' understanding of physical science concepts. A set of four simulation-based PA tasks were iteratively developed to assess student understanding of an array of physical science concepts, including net force,…

  17. Understanding ‘human’ waves: exploiting the physics in a viral video

    Science.gov (United States)

    Ferrer-Roca, Chantal

    2018-01-01

    Waves are a relevant part of physics that students find difficult to grasp, even in those cases in which wave propagation kinematics can be visualized. This may hinder a proper understanding of sound, light or quantum physics phenomena that are explained using a wave model. So-called ‘human’ waves, choreographed by people, have proved to be an advisable way to understand basic wave concepts. Videos are widely used as a teaching resource and can be of considerable help in order to watch and discuss ‘human’ waves provided their quality is reasonably good. In this paper we propose and analyse a video that went viral online and has been revealed to be a useful teaching resource for introductory physics students. It shows a unique and very complete series of wave propagations, including pulses with different polarizations and periodic waves that can hardly be found elsewhere. After a proposal on how to discuss the video qualitatively, a quantitative analysis is carried out (no video-tracker needed), including a determination of the main wave magnitudes such as period, wavelength and propagation speed.

  18. Energy and economic growth: Grounding our understanding in physical reality

    International Nuclear Information System (INIS)

    Ockwell, David G.

    2008-01-01

    This article attempts to summarise the complex, wide ranging and unresolved debate within the economics literature on the possibility of decoupling economic growth from energy use. It explores the difference between neo-classical and ecological economic worldviews and highlights how the ecological economic approach attempts to ground its analysis within the physical limits implied by the laws of thermodynamics. Once these laws are accounted for, the possibility of decoupling economic growth from energy use seems more limited than neo-classical economics implies. Analysis of empirical evidence also demonstrates that observed improvements in GDP/energy use ratios in the USA are better explained by shifts towards higher quality fuels than by improvements in the energy efficiency of technologies. This implies a need to focus on decarbonising energy supply. Furthermore, where energy-efficiency improvements are attempted, they must be considered within the context of a possible rebound effect, which implies that net economy-wide energy savings from energy-efficiency improvements may not be as large as the energy saved directly from the efficiency improvement itself. Both decarbonising energy supply and improving energy efficiency require the rapid development and deployment of new and existing low-carbon technologies. This review therefore concludes by briefly outlining areas of economic thought that have emerged as a result of engagement between economists and experts from other disciplines. They include ecological, evolutionary and institutional economics, all of which can make policy-relevant contributions to achieving a transition to a low-carbon economy

  19. Understanding the Physical Nature of Coronal "EIT Waves".

    Science.gov (United States)

    Long, D M; Bloomfield, D S; Chen, P F; Downs, C; Gallagher, P T; Kwon, R-Y; Vanninathan, K; Veronig, A M; Vourlidas, A; Vršnak, B; Warmuth, A; Žic, T

    2017-01-01

    For almost 20 years the physical nature of globally propagating waves in the solar corona (commonly called "EIT waves") has been controversial and subject to debate. Additional theories have been proposed over the years to explain observations that did not agree with the originally proposed fast-mode wave interpretation. However, the incompatibility of observations made using the Extreme-ultraviolet Imaging Telescope (EIT) onboard the Solar and Heliospheric Observatory with the fast-mode wave interpretation was challenged by differing viewpoints from the twin Solar Terrestrial Relations Observatory spacecraft and data with higher spatial and temporal resolution from the Solar Dynamics Observatory . In this article, we reexamine the theories proposed to explain EIT waves to identify measurable properties and behaviours that can be compared to current and future observations. Most of us conclude that the so-called EIT waves are best described as fast-mode large-amplitude waves or shocks that are initially driven by the impulsive expansion of an erupting coronal mass ejection in the low corona.

  20. Understanding and Modeling Freight Stakeholder Behavior

    Science.gov (United States)

    2012-04-01

    This project developed a conceptual model of private-sector freight stakeholder decisions and interactions for : forecasting freight demands in response to key policy variables. Using East Central Wisconsin as a study area, empirical : models were de...

  1. Understanding Business Models in Pharmacy Schools.

    Science.gov (United States)

    Holdford, David A

    2017-06-01

    The objectives of this article are to define business models, contrast the business models in pharmacy schools, and discuss issues that can arise from misunderstandings about whom pharmacy schools serve and how they do so.

  2. Simulation as an Engine of Physical Scene Understanding

    Science.gov (United States)

    2013-11-05

    Percept Psychophys 16(1):4–8. 29. Zago M , McIntyre J, Senot P, Lacquaniti F (2009) Visuo-motor coordination and in- ternal models for object...Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139 Edited by Richard M . Shiffrin, Indiana University, Bloomington, IN, and...inhabit. ACKNOWLEDGMENTS. We thank N. Kanwisher, E. Vul, T. Ullman, C. Baker, E. Davis, G. Marcus, and J. M . Tenenbaum for suggestions on the

  3. Mathematical understanding of nature essays on amazing physical phenomena and their understanding by mathematicians

    CERN Document Server

    Arnold, V I

    2014-01-01

    This collection of 39 short stories gives the reader a unique opportunity to take a look at the scientific philosophy of Vladimir Arnold, one of the most original contemporary researchers. Topics of the stories included range from astronomy, to mirages, to motion of glaciers, to geometry of mirrors and beyond. In each case Arnold's explanation is both deep and simple, which makes the book interesting and accessible to an extremely broad readership. Original illustrations hand drawn by the author help the reader to further understand and appreciate Arnold's view on the relationship between math

  4. An investigation of meaningful understanding and effectiveness of the implementation of Piagetian and Ausubelian theories in physics instruction

    Science.gov (United States)

    Williams, Karen Ann

    One section of college students (N = 25) enrolled in an algebra-based physics course was selected for a Piagetian-based learning cycle (LC) treatment while a second section (N = 25) studied in an Ausubelian-based meaningful verbal reception learning treatment (MVRL). This study examined the students' overall (concept + problem solving + mental model) meaningful understanding of force, density/Archimedes Principle, and heat. Also examined were students' meaningful understanding as measured by conceptual questions, problems, and mental models. In addition, students' learning orientations were examined. There were no significant posttest differences between the LC and MVRL groups for students' meaningful understanding or learning orientation. Piagetian and Ausubelian theories explain meaningful understanding for each treatment. Students from each treatment increased their meaningful understanding. However, neither group altered their learning orientation. The results of meaningful understanding as measured by conceptual questions, problem solving, and mental models were mixed. Differences were attributed to the weaknesses and strengths of each treatment. This research also examined four variables (treatment, reasoning ability, learning orientation, and prior knowledge) to find which best predicted students' overall meaningful understanding of physics concepts. None of these variables were significant predictors at the.05 level. However, when the same variables were used to predict students' specific understanding (i.e. concept, problem solving, or mental model understanding), the results were mixed. For forces and density/Archimedes Principle, prior knowledge and reasoning ability significantly predicted students' conceptual understanding. For heat, however, reasoning ability was the only significant predictor of concept understanding. Reasoning ability and treatment were significant predictors of students' problem solving for heat and forces. For density

  5. Understanding the Physical Optics Phenomena by Using a Digital Application for Light Propagation

    International Nuclear Information System (INIS)

    Sierra-Sosa, Daniel-Esteban; Angel-Toro, Luciano

    2011-01-01

    Understanding the light propagation on the basis of the Huygens-Fresnel principle stands for a fundamental factor for deeper comprehension of different physical optics related phenomena like diffraction, self-imaging, image formation, Fourier analysis and spatial filtering. This constitutes the physical approach of the Fourier optics whose principles and applications have been developed since the 1950's. Both for analytical and digital applications purposes, light propagation can be formulated in terms of the Fresnel Integral Transform. In this work, a digital optics application based on the implementation of the Discrete Fresnel Transform (DFT), and addressed to serve as a tool for applications in didactics of optics is presented. This tool allows, at a basic and intermediate learning level, exercising with the identification of basic phenomena, and observing changes associated with modifications of physical parameters. This is achieved by using a friendly graphic user interface (GUI). It also assists the user in the development of his capacity for abstracting and predicting the characteristics of more complicated phenomena. At an upper level of learning, the application could be used to favor a deeper comprehension of involved physics and models, and experimenting with new models and configurations. To achieve this, two characteristics of the didactic tool were taken into account when designing it. First, all physical operations, ranging from simple diffraction experiments to digital holography and interferometry, were developed on the basis of the more fundamental concept of light propagation. Second, the algorithm was conceived to be easily upgradable due its modular architecture based in MATLAB (registered) software environment. Typical results are presented and briefly discussed in connection with didactics of optics.

  6. Understanding the Physical Optics Phenomena by Using a Digital Application for Light Propagation

    Energy Technology Data Exchange (ETDEWEB)

    Sierra-Sosa, Daniel-Esteban; Angel-Toro, Luciano, E-mail: dsierras@eafit.edu.co, E-mail: langel@eafit.edu.co [Grupo de Optica Aplicada, Universidad EAFIT, 1 Medellin (Colombia)

    2011-01-01

    Understanding the light propagation on the basis of the Huygens-Fresnel principle stands for a fundamental factor for deeper comprehension of different physical optics related phenomena like diffraction, self-imaging, image formation, Fourier analysis and spatial filtering. This constitutes the physical approach of the Fourier optics whose principles and applications have been developed since the 1950's. Both for analytical and digital applications purposes, light propagation can be formulated in terms of the Fresnel Integral Transform. In this work, a digital optics application based on the implementation of the Discrete Fresnel Transform (DFT), and addressed to serve as a tool for applications in didactics of optics is presented. This tool allows, at a basic and intermediate learning level, exercising with the identification of basic phenomena, and observing changes associated with modifications of physical parameters. This is achieved by using a friendly graphic user interface (GUI). It also assists the user in the development of his capacity for abstracting and predicting the characteristics of more complicated phenomena. At an upper level of learning, the application could be used to favor a deeper comprehension of involved physics and models, and experimenting with new models and configurations. To achieve this, two characteristics of the didactic tool were taken into account when designing it. First, all physical operations, ranging from simple diffraction experiments to digital holography and interferometry, were developed on the basis of the more fundamental concept of light propagation. Second, the algorithm was conceived to be easily upgradable due its modular architecture based in MATLAB (registered) software environment. Typical results are presented and briefly discussed in connection with didactics of optics.

  7. Understanding the Physical Optics Phenomena by Using a Digital Application for Light Propagation

    Science.gov (United States)

    Sierra-Sosa, Daniel-Esteban; Ángel-Toro, Luciano

    2011-01-01

    Understanding the light propagation on the basis of the Huygens-Fresnel principle stands for a fundamental factor for deeper comprehension of different physical optics related phenomena like diffraction, self-imaging, image formation, Fourier analysis and spatial filtering. This constitutes the physical approach of the Fourier optics whose principles and applications have been developed since the 1950's. Both for analytical and digital applications purposes, light propagation can be formulated in terms of the Fresnel Integral Transform. In this work, a digital optics application based on the implementation of the Discrete Fresnel Transform (DFT), and addressed to serve as a tool for applications in didactics of optics is presented. This tool allows, at a basic and intermediate learning level, exercising with the identification of basic phenomena, and observing changes associated with modifications of physical parameters. This is achieved by using a friendly graphic user interface (GUI). It also assists the user in the development of his capacity for abstracting and predicting the characteristics of more complicated phenomena. At an upper level of learning, the application could be used to favor a deeper comprehension of involved physics and models, and experimenting with new models and configurations. To achieve this, two characteristics of the didactic tool were taken into account when designing it. First, all physical operations, ranging from simple diffraction experiments to digital holography and interferometry, were developed on the basis of the more fundamental concept of light propagation. Second, the algorithm was conceived to be easily upgradable due its modular architecture based in MATLAB® software environment. Typical results are presented and briefly discussed in connection with didactics of optics.

  8. Physics-based models of the plasmasphere

    Energy Technology Data Exchange (ETDEWEB)

    Jordanova, Vania K [Los Alamos National Laboratory; Pierrard, Vivane [BELGIUM; Goldstein, Jerry [SWRI; Andr' e, Nicolas [ESTEC/ESA; Kotova, Galina A [SRI, RUSSIA; Lemaire, Joseph F [BELGIUM; Liemohn, Mike W [U OF MICHIGAN; Matsui, H [UNIV OF NEW HAMPSHIRE

    2008-01-01

    We describe recent progress in physics-based models of the plasmasphere using the Auid and the kinetic approaches. Global modeling of the dynamics and inAuence of the plasmasphere is presented. Results from global plasmasphere simulations are used to understand and quantify (i) the electric potential pattern and evolution during geomagnetic storms, and (ii) the inAuence of the plasmasphere on the excitation of electromagnetic ion cyclotron (ElvIIC) waves a.nd precipitation of energetic ions in the inner magnetosphere. The interactions of the plasmasphere with the ionosphere a.nd the other regions of the magnetosphere are pointed out. We show the results of simulations for the formation of the plasmapause and discuss the inAuence of plasmaspheric wind and of ultra low frequency (ULF) waves for transport of plasmaspheric material. Theoretical formulations used to model the electric field and plasma distribution in the plasmasphere are given. Model predictions are compared to recent CLUSTER and MAGE observations, but also to results of earlier models and satellite observations.

  9. Understanding financial crisis through accounting models

    NARCIS (Netherlands)

    Bezemer, D.J.

    2010-01-01

    This paper presents evidence that accounting (or flow-of-funds) macroeconomic models helped anticipate the credit crisis and economic recession Equilibrium models ubiquitous in mainstream policy and research did not This study traces the Intellectual pedigrees of the accounting approach as an

  10. Comparative Approaches to Understanding the Relation Between Aging and Physical Function.

    Science.gov (United States)

    Justice, Jamie N; Cesari, Matteo; Seals, Douglas R; Shively, Carol A; Carter, Christy S

    2016-10-01

    Despite dedicated efforts to identify interventions to delay aging, most promising interventions yielding dramatic life-span extension in animal models of aging are often ineffective when translated to clinical trials. This may be due to differences in primary outcomes between species and difficulties in determining the optimal clinical trial paradigms for translation. Measures of physical function, including brief standardized testing batteries, are currently being proposed as biomarkers of aging in humans, are predictive of adverse health events, disability, and mortality, and are commonly used as functional outcomes for clinical trials. Motor outcomes are now being incorporated into preclinical testing, a positive step toward enhancing our ability to translate aging interventions to clinical trials. To further these efforts, we begin a discussion of physical function and disability assessment across species, with special emphasis on mice, rats, monkeys, and man. By understanding how physical function is assessed in humans, we can tailor measurements in animals to better model those outcomes to establish effective, standardized translational functional assessments with aging. © The Author 2015. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  11. Understanding Resilient Urban Futures: A Systemic Modelling Approach

    Directory of Open Access Journals (Sweden)

    Ralph Chapman

    2013-07-01

    Full Text Available The resilience of cities in response to natural disasters and long-term climate change has emerged as a focus of academic and policy attention. In particular, how to understand the interconnectedness of urban and natural systems is a key issue. This paper introduces an urban model that can be used to evaluate city resilience outcomes under different policy scenarios. The model is the Wellington Integrated Land Use-Transport-Environment Model (WILUTE. It considers the city (i.e., Wellington as a complex system characterized by interactions between a variety of internal urban processes (social, economic and physical and the natural environment. It is focused on exploring the dynamic relations between human activities (the geographic distribution of housing and employment, infrastructure layout, traffic flows and energy consumption, environmental effects (carbon emissions, influences on local natural and ecological systems and potential natural disasters (e.g., inundation due to sea level rise and storm events faced under different policy scenarios. The model gives insights that are potentially useful for policy to enhance the city’s resilience, by modelling outcomes, such as the potential for reduction in transportation energy use, and changes in the vulnerability of the city’s housing stock and transport system to sea level rise.

  12. The Toy model: Understanding the early universe

    Science.gov (United States)

    Fisher, Peter H.; Price, Richard H.

    2018-04-01

    In many branches of science, progress is being made by taking advantage of insights from other branches of science. Cosmology, the structure and evolution of the universe, is certainly an area that is currently beset by problems in understanding. We show here that the scientific insights from the studies of early childhood development, in particular, those of Piaget, give a new way of looking at the early universe. This new approach can not only be invaluable in undergraduate teaching, but can even be the basis of semi-quantitative predictions.

  13. Mouse models for understanding human developmental anomalies

    International Nuclear Information System (INIS)

    Generoso, W.M.

    1989-01-01

    The mouse experimental system presents an opportunity for studying the nature of the underlying mutagenic damage and the molecular pathogenesis of this class of anomalies by virtue of the accessibility of the zygote and its descendant blastomeres. Such studies could contribute to the understanding of the etiology of certain sporadic but common human malformations. The vulnerability of the zygotes to mutagens as demonstrated in the studies described in this report should be a major consideration in chemical safety evaluation. It raises questions regarding the danger to human zygotes when the mother is exposed to drugs and environmental chemicals

  14. Continuum methods of physical modeling continuum mechanics, dimensional analysis, turbulence

    CERN Document Server

    Hutter, Kolumban

    2004-01-01

    The book unifies classical continuum mechanics and turbulence modeling, i.e. the same fundamental concepts are used to derive model equations for material behaviour and turbulence closure and complements these with methods of dimensional analysis. The intention is to equip the reader with the ability to understand the complex nonlinear modeling in material behaviour and turbulence closure as well as to derive or invent his own models. Examples are mostly taken from environmental physics and geophysics.

  15. Evaluating a Model of Youth Physical Activity

    Science.gov (United States)

    Heitzler, Carrie D.; Lytle, Leslie A.; Erickson, Darin J.; Barr-Anderson, Daheia; Sirard, John R.; Story, Mary

    2010-01-01

    Objective: To explore the relationship between social influences, self-efficacy, enjoyment, and barriers and physical activity. Methods: Structural equation modeling examined relationships between parent and peer support, parent physical activity, individual perceptions, and objectively measured physical activity using accelerometers among a…

  16. Modeling and Understanding Time-Evolving Scenarios

    Directory of Open Access Journals (Sweden)

    Riccardo Melen

    2015-08-01

    Full Text Available In this paper, we consider the problem of modeling application scenarios characterized by variability over time and involving heterogeneous kinds of knowledge. The evolution of distributed technologies creates new and challenging possibilities of integrating different kinds of problem solving methods, obtaining many benefits from the user point of view. In particular, we propose here a multilayer modeling system and adopt the Knowledge Artifact concept to tie together statistical and Artificial Intelligence rule-based methods to tackle problems in ubiquitous and distributed scenarios.

  17. What Teachers Understand of Model Lessons

    Science.gov (United States)

    Courtney, Scott A.

    2017-01-01

    Over the past two decades, researchers in mathematics teacher education have identified characteristics of high quality professional development (PD). This report describes an investigation of a common approach to PD with secondary mathematics teachers, providing teachers with opportunities to experience reform-oriented model lessons as students…

  18. Understanding sexual harassment using aggregate construct models.

    Science.gov (United States)

    Nye, Christopher D; Brummel, Bradley J; Drasgow, Fritz

    2014-11-01

    Sexual harassment has received a substantial amount of empirical attention over the past few decades, and this research has consistently shown that experiencing these behaviors has a detrimental effect on employees' well-being, job attitudes, and behaviors at work. However, these findings, and the conclusions that are drawn from them, make the implicit assumption that the empirical models used to examine sexual harassment are properly specified. This article presents evidence that properly specified aggregate construct models are more consistent with theoretical structures and definitions of sexual harassment and can result in different conclusions about the nomological network of harassment. Results from 3 large samples, 2 military and 1 from a civilian population, are used to illustrate the differences between aggregate construct and reflective indicator models of sexual harassment. These analyses suggested that the factor structure and the nomological network of sexual harassment differ when modeling harassment as an aggregate construct. The implications of these results for the continued study of sexual harassment are discussed. (PsycINFO Database Record (c) 2014 APA, all rights reserved).

  19. Understanding physical activity in individuals with prediabetes: an application of social cognitive theory.

    Science.gov (United States)

    Taylor, Lorian M; Raine, Kim D; Plotnikoff, Ronald C; Vallance, Jeff K; Sharma, Arya M; Spence, John C

    2016-01-01

    Despite well-documented evidence implicating physical activity (PA) in the prevention of type 2 diabetes, the overwhelming majority of individuals with prediabetes are not physically active enough. The purpose of this study was to investigate the applicability of the social cognitive theory (SCT) in understanding PA behaviour in individuals with prediabetes. Individuals with prediabetes (N = 232) completed a mailed questionnaire assessing demographics, self-reported PA (MET.min/wk) and SCT constructs for PA MET.min/wk. For PA MET.min/wk, scheduling and task efficacy both had significant effects on PA (β = .30 and .22, respectively). Goal formation also had a direct effect on PA for scheduling, coping and task efficacy (β = .20, .34 and .30, respectively). Task, coping and scheduling efficacy explained a significant portion of the variance in PA behaviour. Overall, SCT appears to have merit as a model for understanding PA in individuals with prediabetes. Further evaluative inquiry is needed to establish support for the use of the SCT as a framework for developing, implementing and evaluating PA behaviour change interventions in this population.

  20. A validated physical model of greenhouse climate.

    NARCIS (Netherlands)

    Bot, G.P.A.

    1989-01-01

    In the greenhouse model the momentaneous environmental crop growth factors are calculated as output, together with the physical behaviour of the crop. The boundary conditions for this model are the outside weather conditions; other inputs are the physical characteristics of the crop, of the

  1. Using a novel environmental quality measure to understand population-level physical inactivity

    Science.gov (United States)

    Physical inactivity has been associated with numerous adverse health outcomes including obesity, heart disease, and depression, and is considered a major contributor to all-cause mortality worldwide. Understanding the role of the overall ambient environment in population inactivi...

  2. Numerical modelling in material physics

    International Nuclear Information System (INIS)

    Proville, L.

    2004-12-01

    The author first briefly presents his past research activities: investigation of a dislocation sliding in solid solution by molecular dynamics, modelling of metal film growth by phase field and Monte Carlo kinetics, phase field model for surface self-organisation, phase field model for the Al 3 Zr alloy, calculation of anharmonic photons, mobility of bipolarons in superconductors. Then, he more precisely reports the mesoscopic modelling in phase field, and some atomistic modelling (dislocation sliding, Monte Carlo simulation of metal surface growth, anharmonic network optical spectrum modelling)

  3. Understanding error generation in fused deposition modeling

    International Nuclear Information System (INIS)

    Bochmann, Lennart; Transchel, Robert; Wegener, Konrad; Bayley, Cindy; Helu, Moneer; Dornfeld, David

    2015-01-01

    Additive manufacturing offers completely new possibilities for the manufacturing of parts. The advantages of flexibility and convenience of additive manufacturing have had a significant impact on many industries, and optimizing part quality is crucial for expanding its utilization. This research aims to determine the sources of imprecision in fused deposition modeling (FDM). Process errors in terms of surface quality, accuracy and precision are identified and quantified, and an error-budget approach is used to characterize errors of the machine tool. It was determined that accuracy and precision in the y direction (0.08–0.30 mm) are generally greater than in the x direction (0.12–0.62 mm) and the z direction (0.21–0.57 mm). Furthermore, accuracy and precision tend to decrease at increasing axis positions. The results of this work can be used to identify possible process improvements in the design and control of FDM technology. (paper)

  4. Understanding error generation in fused deposition modeling

    Science.gov (United States)

    Bochmann, Lennart; Bayley, Cindy; Helu, Moneer; Transchel, Robert; Wegener, Konrad; Dornfeld, David

    2015-03-01

    Additive manufacturing offers completely new possibilities for the manufacturing of parts. The advantages of flexibility and convenience of additive manufacturing have had a significant impact on many industries, and optimizing part quality is crucial for expanding its utilization. This research aims to determine the sources of imprecision in fused deposition modeling (FDM). Process errors in terms of surface quality, accuracy and precision are identified and quantified, and an error-budget approach is used to characterize errors of the machine tool. It was determined that accuracy and precision in the y direction (0.08-0.30 mm) are generally greater than in the x direction (0.12-0.62 mm) and the z direction (0.21-0.57 mm). Furthermore, accuracy and precision tend to decrease at increasing axis positions. The results of this work can be used to identify possible process improvements in the design and control of FDM technology.

  5. Understanding your student: Using the VARK model

    Directory of Open Access Journals (Sweden)

    I J Prithishkumar

    2014-01-01

    Full Text Available Background: Students have different preferences in the assimilation and processing of information. The VARK learning style model introduced by Fleming includes a questionnaire that identifies a person′s sensory modality preference in learning. This model classifies students into four different learning modes; visual (V, aural (A, read/write (R, and kinesthetic (K. Materials and Methods: The 16-point multiple choice VARK questionnaire version 7.1 was distributed to first year undergraduate medical students after obtaining permission for use.Results: Seventy-nine students (86.8% were multimodal in their learning preference, and 12 students (13.8% were unimodal. The highest unimodal preference was K-7.7%. Surprisingly, there were no visual unimodal learners. The commonest learning preference was the bimodal category, of which the highest percentage was seen in the AK (33% and AR (16.5% category. The most common trimodal preference was ARK (8.9%. The total individual scores in each category were V-371, A-588, R/W-432, and K-581; auditory and kinesthetic being the highest preference. Visual mode had the lowest overall score. There was no significant difference in preference between the sexes. Conclusion: Students possess a wide diversity in learning preferences. This necessitates teachers to effectively deliver according to the needs of the student. Multiple modalities of information presentation are necessary to keep the attention and motivation of our students requiring a shift from the traditional large-group teacher-centric lecture method to an interactive, student-centric multimodal approach.

  6. Prospective Physics Teachers' Level of Understanding Energy, Power and Force Concepts

    Science.gov (United States)

    Saglam-Arslan, Aysegul; Kurnaz, Mehmet Altan

    2009-01-01

    The aim of this study is to determine prospective physics teachers' level of understanding of the concepts of energy and the related concepts of force and power. The study was carried out with the participation of 56 physics education department students at a university in Karadeniz region. All participants had previously taken an introductory…

  7. Student Teachers' Levels of Understanding and Model of Understanding about Newton's Laws of Motion

    Science.gov (United States)

    Saglam-Arslan, Aysegul; Devecioglu, Yasemin

    2010-01-01

    This study was conducted to determine the level of student teachers' understandings of Newton's laws of motion and relating these levels to identify student teachers' models of understanding. An achievement test composed of two parts comprising 12 open ended questions was constructed and given to 45 pre-service classroom teachers. The first part…

  8. Understanding Etna flank instability through numerical models

    Science.gov (United States)

    Apuani, Tiziana; Corazzato, Claudia; Merri, Andrea; Tibaldi, Alessandro

    2013-02-01

    As many active volcanoes, Mount Etna shows clear evidence of flank instability, and different mechanisms were suggested to explain this flank dynamics, based on the recorded deformation pattern and character. Shallow and deep deformations, mainly associated with both eruptive and seismic events, are concentrated along recognised fracture and fault systems, mobilising the eastern and south-eastern flank of the volcano. Several interacting causes were postulated to control the phenomenon, including gravity force, magma ascent along the feeding system, and a very complex local and/or regional tectonic activity. Nevertheless, the complexity of such dynamics is still an open subject of research and being the volcano flanks heavily urbanised, the comprehension of the gravitative dynamics is a major issue for public safety and civil protection. The present research explores the effects of the main geological features (in particular the role of the subetnean clays, interposed between the Apennine-Maghrebian flysch and the volcanic products) and the role of weakness zones, identified by fracture and fault systems, on the slope instability process. The effects of magma intrusions are also investigated. The problem is addressed by integrating field data, laboratory tests and numerical modelling. A bi- and tri-dimensional stress-strain analysis was performed by a finite difference numerical code (FLAC and FLAC3D), mainly aimed at evaluating the relationship among geological features, volcano-tectonic structures and magmatic activity in controlling the deformation processes. The analyses are well supported by dedicated structural-mechanical field surveys, which allowed to estimate the rock mass strength and deformability parameters. To take into account the uncertainties which inevitably occur in a so complicated model, many efforts were done in performing a sensitivity analysis along a WNW-ESE section crossing the volcano summit and the Valle del Bove depression. This was

  9. “Using Statistical Comparisons between SPartICus Cirrus Microphysical Measurements, Detailed Cloud Models, and GCM Cloud Parameterizations to Understand Physical Processes Controlling Cirrus Properties and to Improve the Cloud Parameterizations”

    Energy Technology Data Exchange (ETDEWEB)

    Woods, Sarah [SPEC Inc., Boulder, CO (United States)

    2015-12-01

    The dual objectives of this project were improving our basic understanding of processes that control cirrus microphysical properties and improvement of the representation of these processes in the parameterizations. A major effort in the proposed research was to integrate, calibrate, and better understand the uncertainties in all of these measurements.

  10. Effect of Linked Rules on Business Process Model Understanding

    DEFF Research Database (Denmark)

    Wang, Wei; Indulska, Marta; Sadiq, Shazia

    2017-01-01

    Business process models are widely used in organizations by information systems analysts to represent complex business requirements and by business users to understand business operations and constraints. This understanding is extracted from graphical process models as well as business rules. Prior...

  11. Videogame Construction by Engineering Students for Understanding Modelling Processes: The Case of Simulating Water Behaviour

    Science.gov (United States)

    Pretelín-Ricárdez, Angel; Sacristán, Ana Isabel

    2015-01-01

    We present some results of an ongoing research project where university engineering students were asked to construct videogames involving the use of physical systems models. The objective is to help them identify and understand the elements and concepts involved in the modelling process. That is, we use game design as a constructionist approach…

  12. High precision Standard Model Physics

    International Nuclear Information System (INIS)

    Magnin, J.

    2009-01-01

    The main goal of the LHCb experiment, one of the four large experiments of the Large Hadron Collider, is to try to give answers to the question of why Nature prefers matter over antimatter? This will be done by studying the decay of b quarks and their antimatter partners, b-bar, which will be produced by billions in 14 TeV p-p collisions by the LHC. In addition, as 'beauty' particles mainly decay in charm particles, an interesting program of charm physics will be carried on, allowing to measure quantities as for instance the D 0 -D-bar 0 mixing, with incredible precision.

  13. No Space for Girliness in Physics: Understanding and Overcoming the Masculinity of Physics

    Science.gov (United States)

    Götschel, Helene

    2014-01-01

    Allison Gonsalves' article on "women doctoral students' positioning around discourses of gender and competence in physics" explores narratives of Canadian women physicists concerning their strategies to gain recognition as physicists. In my response to her rewarding and inspiring analysis I will reflect on her findings and arguments and…

  14. Physics Based Modeling of Compressible Turbulance

    Science.gov (United States)

    2016-11-07

    AFRL-AFOSR-VA-TR-2016-0345 PHYSICS -BASED MODELING OF COMPRESSIBLE TURBULENCE PARVIZ MOIN LELAND STANFORD JUNIOR UNIV CA Final Report 09/13/2016...on the AFOSR project (FA9550-11-1-0111) entitled: Physics based modeling of compressible turbulence. The period of performance was, June 15, 2011...by ANSI Std. Z39.18 Page 1 of 2FORM SF 298 11/10/2016https://livelink.ebs.afrl.af.mil/livelink/llisapi.dll PHYSICS -BASED MODELING OF COMPRESSIBLE

  15. Using participatory approaches with children to better understand their physical activity behaviour

    DEFF Research Database (Denmark)

    Hayball, Felicity Z.L.; Pawlowski, Charlotte Skau

    2018-01-01

    Aims and objectives: The importance of childhood physical activity is widely recognised. Helping children to articulate their opinions is a crucial factor in improving their health and well-being, yet the field is predominantly focused on adult-led quantitative methods and lacks deeper understand......Aims and objectives: The importance of childhood physical activity is widely recognised. Helping children to articulate their opinions is a crucial factor in improving their health and well-being, yet the field is predominantly focused on adult-led quantitative methods and lacks deeper...... physical activity in these places (n = 25). Results: The benefits and challenges associated with using participatory methods to understand how children perceive the environment in relation to their physical activity behaviour are described. Conclusion: Findings contribute to the literature by suggesting...... that participatory approaches are valuable in capturing children’s perceptions of physical activity behaviour in outdoor environments....

  16. The limitations of mathematical modeling in high school physics education

    Science.gov (United States)

    Forjan, Matej

    The theme of the doctoral dissertation falls within the scope of didactics of physics. Theoretical analysis of the key constraints that occur in the transmission of mathematical modeling of dynamical systems into field of physics education in secondary schools is presented. In an effort to explore the extent to which current physics education promotes understanding of models and modeling, we analyze the curriculum and the three most commonly used textbooks for high school physics. We focus primarily on the representation of the various stages of modeling in the solved tasks in textbooks and on the presentation of certain simplifications and idealizations, which are in high school physics frequently used. We show that one of the textbooks in most cases fairly and reasonably presents the simplifications, while the other two half of the analyzed simplifications do not explain. It also turns out that the vast majority of solved tasks in all the textbooks do not explicitly represent model assumptions based on what we can conclude that in high school physics the students do not develop sufficiently a sense of simplification and idealizations, which is a key part of the conceptual phase of modeling. For the introduction of modeling of dynamical systems the knowledge of students is also important, therefore we performed an empirical study on the extent to which high school students are able to understand the time evolution of some dynamical systems in the field of physics. The research results show the students have a very weak understanding of the dynamics of systems in which the feedbacks are present. This is independent of the year or final grade in physics and mathematics. When modeling dynamical systems in high school physics we also encounter the limitations which result from the lack of mathematical knowledge of students, because they don't know how analytically solve the differential equations. We show that when dealing with one-dimensional dynamical systems

  17. The Physical Internet and Business Model Innovation

    Directory of Open Access Journals (Sweden)

    Diane Poulin

    2012-06-01

    Full Text Available Building on the analogy of data packets within the Digital Internet, the Physical Internet is a concept that dramatically transforms how physical objects are designed, manufactured, and distributed. This approach is open, efficient, and sustainable beyond traditional proprietary logistical solutions, which are often plagued by inefficiencies. The Physical Internet redefines supply chain configurations, business models, and value-creation patterns. Firms are bound to be less dependent on operational scale and scope trade-offs because they will be in a position to offer novel hybrid products and services that would otherwise destroy value. Finally, logistical chains become flexible and reconfigurable in real time, thus becoming better in tune with firm strategic choices. This article focuses on the potential impact of the Physical Internet on business model innovation, both from the perspectives of Physical-Internet enabled and enabling business models.

  18. Understanding acoustic physics in oil and gas wellbores with the presence of ubiquitous geometric eccentricity

    Science.gov (United States)

    Liu, Yang; D'Angelo, Ralph M.; Choi, Gloria; Zhu, Lingchen; Bose, Sandip; Zeroug, Smaine

    2018-04-01

    Once an oil and gas wellbore has been drilled, steel casings and cement slurry are placed to ensure structural support, protection from fluid invasion, and most importantly to provide zonal isolation. The actual wellbore and string structure is rarely concentric but rather is often an eccentric one, especially in deviated boreholes. The term "eccentricity" is used to describe how off-center a casing string is within another pipe or the open-hole. In a typical double-string configuration, the inner casing is eccentered with respect to the outer string which itself is also eccentered within the cylindrical hole. The annuli may or may not be filled with solid cement, and the cement may have liquid-filled channels or be disbonded over localized azimuthal ranges. The complexity of wave propagation along axial intervals is significant in that multiple modes can be excited and detected with characteristics that are affected by the various parameters, including eccentering, in a non-linear fashion. A successful diagnosis of cement flaws largely relies on a thorough understanding of the complex acoustic modal information. The present study employs both modeling and experiments to fully understand the acoustic wave propagation in the complex, fluid-solid nested, cylindrically layered structures, with geometric eccentricities. The experimental results show excellent agreement with the theoretical predictions from newly developed, borehole acoustic modeling approaches. As such, it provides the basis for better understanding the operative wave physics and providing the means for effective inspection methodologies to assess well integrity and zonal isolation of oil wells.

  19. Driven by Beliefs: Understanding Challenges Physical Science Teachers Face When Integrating Engineering and Physics

    Science.gov (United States)

    Dare, Emily A.; Ellis, Joshua A.; Roehrig, Gillian H.

    2014-01-01

    It is difficult to ignore the increased use of technological innovations in today's world, which has led to various calls for the integration of engineering into K-12 science standards. The need to understand how engineering is currently being brought to science classrooms is apparent and necessary in order to address these calls for integration.…

  20. Are Physical Education Majors Models for Fitness?

    Science.gov (United States)

    Kamla, James; Snyder, Ben; Tanner, Lori; Wash, Pamela

    2012-01-01

    The National Association of Sport and Physical Education (NASPE) (2002) has taken a firm stance on the importance of adequate fitness levels of physical education teachers stating that they have the responsibility to model an active lifestyle and to promote fitness behaviors. Since the NASPE declaration, national initiatives like Let's Move…

  1. "Let's get physical": advantages of a physical model over 3D computer models and textbooks in learning imaging anatomy.

    Science.gov (United States)

    Preece, Daniel; Williams, Sarah B; Lam, Richard; Weller, Renate

    2013-01-01

    Three-dimensional (3D) information plays an important part in medical and veterinary education. Appreciating complex 3D spatial relationships requires a strong foundational understanding of anatomy and mental 3D visualization skills. Novel learning resources have been introduced to anatomy training to achieve this. Objective evaluation of their comparative efficacies remains scarce in the literature. This study developed and evaluated the use of a physical model in demonstrating the complex spatial relationships of the equine foot. It was hypothesized that the newly developed physical model would be more effective for students to learn magnetic resonance imaging (MRI) anatomy of the foot than textbooks or computer-based 3D models. Third year veterinary medicine students were randomly assigned to one of three teaching aid groups (physical model; textbooks; 3D computer model). The comparative efficacies of the three teaching aids were assessed through students' abilities to identify anatomical structures on MR images. Overall mean MRI assessment scores were significantly higher in students utilizing the physical model (86.39%) compared with students using textbooks (62.61%) and the 3D computer model (63.68%) (P < 0.001), with no significant difference between the textbook and 3D computer model groups (P = 0.685). Student feedback was also more positive in the physical model group compared with both the textbook and 3D computer model groups. Our results suggest that physical models may hold a significant advantage over alternative learning resources in enhancing visuospatial and 3D understanding of complex anatomical architecture, and that 3D computer models have significant limitations with regards to 3D learning. © 2013 American Association of Anatomists.

  2. Quark models in hadron physics

    International Nuclear Information System (INIS)

    Phatak, Shashikant C.

    2007-01-01

    In this talk, we review the role played by the quark models in the study of interaction of strong, weak and electromagnetic probes with hadrons at intermediate and high momentum transfers. By hadrons, we mean individual nucleons as well as nuclei. We argue that at these momentum transfers, the structure of hadrons plays an important role. The hadron structure of the hadrons is because of the underlying quark structure of hadrons and therefore the quark models play an important role in determining the hadron structure. Further, the properties of hadrons are likely to change when these are placed in nuclear medium and this change should arise from the underlying quark structure. We shall consider some quark models to look into these aspects. (author)

  3. New physics beyond the standard model of particle physics and parallel universes

    Energy Technology Data Exchange (ETDEWEB)

    Plaga, R. [Franzstr. 40, 53111 Bonn (Germany)]. E-mail: rainer.plaga@gmx.de

    2006-03-09

    It is shown that if-and only if-'parallel universes' exist, an electroweak vacuum that is expected to have decayed since the big bang with a high probability might exist. It would neither necessarily render our existence unlikely nor could it be observed. In this special case the observation of certain combinations of Higgs-boson and top-quark masses-for which the standard model predicts such a decay-cannot be interpreted as evidence for new physics at low energy scales. The question of whether parallel universes exist is of interest to our understanding of the standard model of particle physics.

  4. Physics of the Quark Model

    Science.gov (United States)

    Young, Robert D.

    1973-01-01

    Discusses the charge independence, wavefunctions, magnetic moments, and high-energy scattering of hadrons on the basis of group theory and nonrelativistic quark model with mass spectrum calculated by first-order perturbation theory. The presentation is explainable to advanced undergraduate students. (CC)

  5. Simplified Models for LHC New Physics Searches

    CERN Document Server

    Alves, Daniele; Arora, Sanjay; Bai, Yang; Baumgart, Matthew; Berger, Joshua; Buckley, Matthew; Butler, Bart; Chang, Spencer; Cheng, Hsin-Chia; Cheung, Clifford; Chivukula, R.Sekhar; Cho, Won Sang; Cotta, Randy; D'Alfonso, Mariarosaria; El Hedri, Sonia; Essig, Rouven; Evans, Jared A.; Fitzpatrick, Liam; Fox, Patrick; Franceschini, Roberto; Freitas, Ayres; Gainer, James S.; Gershtein, Yuri; Gray, Richard; Gregoire, Thomas; Gripaios, Ben; Gunion, Jack; Han, Tao; Haas, Andy; Hansson, Per; Hewett, JoAnne; Hits, Dmitry; Hubisz, Jay; Izaguirre, Eder; Kaplan, Jared; Katz, Emanuel; Kilic, Can; Kim, Hyung-Do; Kitano, Ryuichiro; Koay, Sue Ann; Ko, Pyungwon; Krohn, David; Kuflik, Eric; Lewis, Ian; Lisanti, Mariangela; Liu, Tao; Liu, Zhen; Lu, Ran; Luty, Markus; Meade, Patrick; Morrissey, David; Mrenna, Stephen; Nojiri, Mihoko; Okui, Takemichi; Padhi, Sanjay; Papucci, Michele; Park, Michael; Park, Myeonghun; Perelstein, Maxim; Peskin, Michael; Phalen, Daniel; Rehermann, Keith; Rentala, Vikram; Roy, Tuhin; Ruderman, Joshua T.; Sanz, Veronica; Schmaltz, Martin; Schnetzer, Stephen; Schuster, Philip; Schwaller, Pedro; Schwartz, Matthew D.; Schwartzman, Ariel; Shao, Jing; Shelton, Jessie; Shih, David; Shu, Jing; Silverstein, Daniel; Simmons, Elizabeth; Somalwar, Sunil; Spannowsky, Michael; Spethmann, Christian; Strassler, Matthew; Su, Shufang; Tait, Tim; Thomas, Brooks; Thomas, Scott; Toro, Natalia; Volansky, Tomer; Wacker, Jay; Waltenberger, Wolfgang; Yavin, Itay; Yu, Felix; Zhao, Yue; Zurek, Kathryn

    2012-01-01

    This document proposes a collection of simplified models relevant to the design of new-physics searches at the LHC and the characterization of their results. Both ATLAS and CMS have already presented some results in terms of simplified models, and we encourage them to continue and expand this effort, which supplements both signature-based results and benchmark model interpretations. A simplified model is defined by an effective Lagrangian describing the interactions of a small number of new particles. Simplified models can equally well be described by a small number of masses and cross-sections. These parameters are directly related to collider physics observables, making simplified models a particularly effective framework for evaluating searches and a useful starting point for characterizing positive signals of new physics. This document serves as an official summary of the results from the "Topologies for Early LHC Searches" workshop, held at SLAC in September of 2010, the purpose of which was to develop a...

  6. Physics of Financial Markets: Can we Understand the Unpredictable Phenomenon of Flash Crashes

    Science.gov (United States)

    Stanley, H. Eugene

    2015-03-01

    Dangerous vulnerability is hiding in complex systems. Indeed, disasters ranging from abrupt financial ``flash crashes'' and large-scale power outages to sudden death among the elderly dramatically exemplify this fact. While we can understand the cause of most events in complex systems, sudden unexpected ``black swans'' whether in economics or in the ``physicists world'' cry out for insight. To design more resilient systems we will describe recent results seeking understanding of these black swans. In many real-world phenomena, such as brain seizures in neuroscience or sudden market crashes in finance, after an inactive period of time a significant part of the damaged network is capable of spontaneously becoming active again. The process often occurs repeatedly. To model this marked network recovery, we examine the effect of local node recoveries and stochastic contiguous spreading, and find that they can lead to the spontaneous emergence of macroscopic ``phase-flipping'' phenomena. The fraction of active nodes switches back and forth between the two network collective modes characterized by high network activity and low network activity. Furthermore, the system exhibits a strong hysteresis behavior analogous to phase transitions near a critical point [A. Majdandzic, B. Podobnik, S. V. Buldyrev, D. Y. Kenett, S. Havlin, and H. E. Stanley, ``Spontaneous Recovery in Dynamic Networks,'' Nature Physics 10, 34 (2014)]. This work was carried out in collaboration with a number of colleagues, chief among whom are A. Majdanzic, B. Podobnik, S. V. Buldyrev, D. Y. Kenett, and S. Havlin.

  7. Modeling Cyber Physical War Gaming

    Science.gov (United States)

    2017-08-07

    games share similar constructs. We also provide a game-theoretic approach to mathematically analyze attacker and defender strategies in cyber war...Military Practice of Course-of-Action Analysis 4 2. Game-Theoretic Method 7 2.1 Mathematical Model 7 2.2 Strategy Selection 10 2.2.1 Pure...officers, hundreds of combat and support vehicles, helicopters, sophisticated intelligence and communication equipment and specialists , artillery and

  8. Physics beyond the Standard Model

    Science.gov (United States)

    Lach, Theodore

    2011-04-01

    Recent discoveries of the excited states of the Bs** meson along with the discovery of the omega-b-minus have brought into popular acceptance the concept of the orbiting quarks predicted by the Checker Board Model (CBM) 14 years ago. Back then the concept of orbiting quarks was not fashionable. Recent estimates of velocities of these quarks inside the proton and neutron are in excess of 90% the speed of light also in agreement with the CBM model. Still a 2D structure of the nucleus has not been accepted nor has it been proven wrong. The CBM predicts masses of the up and dn quarks are 237.31 MeV and 42.392 MeV respectively and suggests that a lighter generation of quarks u and d make up a different generation of quarks that make up light mesons. The CBM also predicts that the T' and B' quarks do exist and are not as massive as might be expected. (this would make it a 5G world in conflict with the SM) The details of the CB model and prediction of quark masses can be found at: http://checkerboard.dnsalias.net/ (1). T.M. Lach, Checkerboard Structure of the Nucleus, Infinite Energy, Vol. 5, issue 30, (2000). (2). T.M. Lach, Masses of the Sub-Nuclear Particles, nucl-th/0008026, @http://xxx.lanl.gov/.

  9. Understanding and Improving Ocean Mixing Parameterizations for modeling Climate Change

    Science.gov (United States)

    Howard, A. M.; Fells, J.; Clarke, J.; Cheng, Y.; Canuto, V.; Dubovikov, M. S.

    2017-12-01

    Climate is vital. Earth is only habitable due to the atmosphere&oceans' distribution of energy. Our Greenhouse Gas emissions shift overall the balance between absorbed and emitted radiation causing Global Warming. How much of these emissions are stored in the ocean vs. entering the atmosphere to cause warming and how the extra heat is distributed depends on atmosphere&ocean dynamics, which we must understand to know risks of both progressive Climate Change and Climate Variability which affect us all in many ways including extreme weather, floods, droughts, sea-level rise and ecosystem disruption. Citizens must be informed to make decisions such as "business as usual" vs. mitigating emissions to avert catastrophe. Simulations of Climate Change provide needed knowledge but in turn need reliable parameterizations of key physical processes, including ocean mixing, which greatly impacts transport&storage of heat and dissolved CO2. The turbulence group at NASA-GISS seeks to use physical theory to improve parameterizations of ocean mixing, including smallscale convective, shear driven, double diffusive, internal wave and tidal driven vertical mixing, as well as mixing by submesoscale eddies, and lateral mixing along isopycnals by mesoscale eddies. Medgar Evers undergraduates aid NASA research while learning climate science and developing computer&math skills. We write our own programs in MATLAB and FORTRAN to visualize and process output of ocean simulations including producing statistics to help judge impacts of different parameterizations on fidelity in reproducing realistic temperatures&salinities, diffusivities and turbulent power. The results can help upgrade the parameterizations. Students are introduced to complex system modeling and gain deeper appreciation of climate science and programming skills, while furthering climate science. We are incorporating climate projects into the Medgar Evers college curriculum. The PI is both a member of the turbulence group at

  10. Ladder physics in the spin fermion model

    Science.gov (United States)

    Tsvelik, A. M.

    2017-05-01

    A link is established between the spin fermion (SF) model of the cuprates and the approach based on the analogy between the physics of doped Mott insulators in two dimensions and the physics of fermionic ladders. This enables one to use nonperturbative results derived for fermionic ladders to move beyond the large-N approximation in the SF model. It is shown that the paramagnon exchange postulated in the SF model has exactly the right form to facilitate the emergence of the fully gapped d -Mott state in the region of the Brillouin zone at the hot spots of the Fermi surface. Hence, the SF model provides an adequate description of the pseudogap.

  11. Ontology modeling in physical asset integrity management

    CERN Document Server

    Yacout, Soumaya

    2015-01-01

    This book presents cutting-edge applications of, and up-to-date research on, ontology engineering techniques in the physical asset integrity domain. Though a survey of state-of-the-art theory and methods on ontology engineering, the authors emphasize essential topics including data integration modeling, knowledge representation, and semantic interpretation. The book also reflects novel topics dealing with the advanced problems of physical asset integrity applications such as heterogeneity, data inconsistency, and interoperability existing in design and utilization. With a distinctive focus on applications relevant in heavy industry, Ontology Modeling in Physical Asset Integrity Management is ideal for practicing industrial and mechanical engineers working in the field, as well as researchers and graduate concerned with ontology engineering in physical systems life cycles. This book also: Introduces practicing engineers, research scientists, and graduate students to ontology engineering as a modeling techniqu...

  12. Developing Understanding of Mathematical Modeling in Secondary Teacher Preparation

    Science.gov (United States)

    Anhalt, Cynthia Oropesa; Cortez, Ricardo

    2016-01-01

    This study examines the evolution of 11 prospective teachers' understanding of mathematical modeling through the implementation of a modeling module within a curriculum course in a secondary teacher preparation program. While the prospective teachers had not previously taken a course on mathematical modeling, they will be expected to include…

  13. A cognitive framework for analyzing and describing introductory students' use and understanding of mathematics in physics

    Science.gov (United States)

    Tuminaro, Jonathan

    Many introductory, algebra-based physics students perform poorly on mathematical problem solving tasks in physics. There are at least two possible, distinct reasons for this poor performance: (1) students simply lack the mathematical skills needed to solve problems in physics, or (2) students do not know how to apply the mathematical skills they have to particular problem situations in physics. While many students do lack the requisite mathematical skills, a major finding from this work is that the majority of students possess the requisite mathematical skills, yet fail to use or interpret them in the context of physics. In this thesis I propose a theoretical framework to analyze and describe students' mathematical thinking in physics. In particular, I attempt to answer two questions. What are the cognitive tools involved in formal mathematical thinking in physics? And, why do students make the kinds of mistakes they do when using mathematics in physics? According to the proposed theoretical framework there are three major theoretical constructs: mathematical resources, which are the knowledge elements that are activated in mathematical thinking and problem solving; epistemic games, which are patterns of activities that use particular kinds of knowledge to create new knowledge or solve a problem; and frames, which are structures of expectations that determine how individuals interpret situations or events. The empirical basis for this study comes from videotaped sessions of college students solving homework problems. The students are enrolled in an algebra-based introductory physics course. The videotapes were transcribed and analyzed using the aforementioned theoretical framework. Two important results from this work are: (1) the construction of a theoretical framework that offers researchers a vocabulary (ontological classification of cognitive structures) and grammar (relationship between the cognitive structures) for understanding the nature and origin of

  14. Understanding the medical markers of elder abuse and neglect: physical examination findings.

    Science.gov (United States)

    Gibbs, Lisa M

    2014-11-01

    A specific foundation of knowledge is important for evaluating potential abuse from physical findings in the older adult. The standard physical examination is a foundation for detecting many types of abuse. An understanding of traumatic injuries, including patterns of injury, is important for health care providers, and inclusion of elder abuse in the differential diagnosis of patient care is essential. One must possess the skills needed to piece the history, including functional capabilities, and physical findings together. Armed with this skill set, health care providers will develop the confidence needed to identify and intervene in cases of elder abuse. Copyright © 2014 Elsevier Inc. All rights reserved.

  15. Utilities for high performance dispersion model PHYSIC

    International Nuclear Information System (INIS)

    Yamazawa, Hiromi

    1992-09-01

    The description and usage of the utilities for the dispersion calculation model PHYSIC were summarized. The model was developed in the study of developing high performance SPEEDI with the purpose of introducing meteorological forecast function into the environmental emergency response system. The procedure of PHYSIC calculation consists of three steps; preparation of relevant files, creation and submission of JCL, and graphic output of results. A user can carry out the above procedure with the help of the Geographical Data Processing Utility, the Model Control Utility, and the Graphic Output Utility. (author)

  16. Modelling Monsoons: Understanding and Predicting Current and Future Behaviour

    Energy Technology Data Exchange (ETDEWEB)

    Turner, A; Sperber, K R; Slingo, J M; Meehl, G A; Mechoso, C R; Kimoto, M; Giannini, A

    2008-09-16

    The global monsoon system is so varied and complex that understanding and predicting its diverse behaviour remains a challenge that will occupy modellers for many years to come. Despite the difficult task ahead, an improved monsoon modelling capability has been realized through the inclusion of more detailed physics of the climate system and higher resolution in our numerical models. Perhaps the most crucial improvement to date has been the development of coupled ocean-atmosphere models. From subseasonal to interdecadal timescales, only through the inclusion of air-sea interaction can the proper phasing and teleconnections of convection be attained with respect to sea surface temperature variations. Even then, the response to slow variations in remote forcings (e.g., El Nino-Southern Oscillation) does not result in a robust solution, as there are a host of competing modes of variability that must be represented, including those that appear to be chaotic. Understanding the links between monsoons and land surface processes is not as mature as that explored regarding air-sea interactions. A land surface forcing signal appears to dominate the onset of wet season rainfall over the North American monsoon region, though the relative role of ocean versus land forcing remains a topic of investigation in all the monsoon systems. Also, improved forecasts have been made during periods in which additional sounding observations are available for data assimilation. Thus, there is untapped predictability that can only be attained through the development of a more comprehensive observing system for all monsoon regions. Additionally, improved parameterizations - for example, of convection, cloud, radiation, and boundary layer schemes as well as land surface processes - are essential to realize the full potential of monsoon predictability. Dynamical considerations require ever increased horizontal resolution (probably to 0.5 degree or higher) in order to resolve many monsoon features

  17. Waste Feed Evaporation Physical Properties Modeling

    International Nuclear Information System (INIS)

    Daniel, W.E.

    2003-01-01

    This document describes the waste feed evaporator modeling work done in the Waste Feed Evaporation and Physical Properties Modeling test specification and in support of the Hanford River Protection Project (RPP) Waste Treatment Plant (WTP) project. A private database (ZEOLITE) was developed and used in this work in order to include the behavior of aluminosilicates such a NAS-gel in the OLI/ESP simulations, in addition to the development of the mathematical models. Mathematical models were developed that describe certain physical properties in the Hanford RPP-WTP waste feed evaporator process (FEP). In particular, models were developed for the feed stream to the first ultra-filtration step characterizing its heat capacity, thermal conductivity, and viscosity, as well as the density of the evaporator contents. The scope of the task was expanded to include the volume reduction factor across the waste feed evaporator (total evaporator feed volume/evaporator bottoms volume). All the physical properties were modeled as functions of the waste feed composition, temperature, and the high level waste recycle volumetric flow rate relative to that of the waste feed. The goal for the mathematical models was to predict the physical property to predicted simulation value. The simulation model approximating the FEP process used to develop the correlations was relatively complex, and not possible to duplicate within the scope of the bench scale evaporation experiments. Therefore, simulants were made of 13 design points (a subset of the points used in the model fits) using the compositions of the ultra-filtration feed streams as predicted by the simulation model. The chemistry and physical properties of the supernate (the modeled stream) as predicted by the simulation were compared with the analytical results of experimental simulant work as a method of validating the simulation software

  18. A study on the intrusion model by physical modeling

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jung Yul; Kim, Yoo Sung; Hyun, Hye Ja [Korea Inst. of Geology Mining and Materials, Taejon (Korea, Republic of)

    1995-12-01

    In physical modeling, the actual phenomena of seismic wave propagation are directly measured like field survey and furthermore the structure and physical properties of subsurface can be known. So the measured datasets from physical modeling can be very desirable as input data to test the efficiency of various inversion algorithms. An underground structure formed by intrusion, which can be often seen in seismic section for oil exploration, is investigated by physical modeling. The model is characterized by various types of layer boundaries with steep dip angle. Therefore, this physical modeling data are very available not only to interpret seismic sections for oil exploration as a case history, but also to develop data processing techniques and estimate the capability of software such as migration, full waveform inversion. (author). 5 refs., 18 figs.

  19. Understanding complex urban systems integrating multidisciplinary data in urban models

    CERN Document Server

    Gebetsroither-Geringer, Ernst; Atun, Funda; Werner, Liss

    2016-01-01

    This book is devoted to the modeling and understanding of complex urban systems. This second volume of Understanding Complex Urban Systems focuses on the challenges of the modeling tools, concerning, e.g., the quality and quantity of data and the selection of an appropriate modeling approach. It is meant to support urban decision-makers—including municipal politicians, spatial planners, and citizen groups—in choosing an appropriate modeling approach for their particular modeling requirements. The contributors to this volume are from different disciplines, but all share the same goal: optimizing the representation of complex urban systems. They present and discuss a variety of approaches for dealing with data-availability problems and finding appropriate modeling approaches—and not only in terms of computer modeling. The selection of articles featured in this volume reflect a broad variety of new and established modeling approaches such as: - An argument for using Big Data methods in conjunction with Age...

  20. Plasma simulation studies using multilevel physics models

    International Nuclear Information System (INIS)

    Park, W.; Belova, E.V.; Fu, G.Y.; Tang, X.Z.; Strauss, H.R.; Sugiyama, L.E.

    1999-01-01

    The question of how to proceed toward ever more realistic plasma simulation studies using ever increasing computing power is addressed. The answer presented here is the M3D (Multilevel 3D) project, which has developed a code package with a hierarchy of physics levels that resolve increasingly complete subsets of phase-spaces and are thus increasingly more realistic. The rationale for the multilevel physics models is given. Each physics level is described and examples of its application are given. The existing physics levels are fluid models (3D configuration space), namely magnetohydrodynamic (MHD) and two-fluids; and hybrid models, namely gyrokinetic-energetic-particle/MHD (5D energetic particle phase-space), gyrokinetic-particle-ion/fluid-electron (5D ion phase-space), and full-kinetic-particle-ion/fluid-electron level (6D ion phase-space). Resolving electron phase-space (5D or 6D) remains a future project. Phase-space-fluid models are not used in favor of δf particle models. A practical and accurate nonlinear fluid closure for noncollisional plasmas seems not likely in the near future. copyright 1999 American Institute of Physics

  1. Physically realistic modeling of maritime training simulation

    OpenAIRE

    Cieutat , Jean-Marc

    2003-01-01

    Maritime training simulation is an important matter of maritime teaching, which requires a lot of scientific and technical skills.In this framework, where the real time constraint has to be maintained, all physical phenomena cannot be studied; the most visual physical phenomena relating to the natural elements and the ship behaviour are reproduced only. Our swell model, based on a surface wave simulation approach, permits to simulate the shape and the propagation of a regular train of waves f...

  2. Understanding Quality in Process Modelling: Towards a Holistic Perspective

    Directory of Open Access Journals (Sweden)

    Jan Recker

    2007-09-01

    Full Text Available Quality is one of the main topics in current conceptual modelling research, as is the field of business process modelling. Yet, widely acknowledged academic contributions towards an understanding or measurement of business process model quality are limited at best. In this paper I argue that the development of methodical theories concerning the measurement or establishment of process model quality must be preceded by methodological elaborations on business process modelling. I further argue that existing epistemological foundations of process modelling are insufficient for describing all extrinsic and intrinsic traits of model quality. This in turn has led to a lack of holistic understanding of process modelling. Taking into account the inherent social and purpose-oriented character of process modelling in contemporary organizations I present a socio-pragmatic constructionist methodology of business process modelling and sketch out implications of this perspective towards an understanding of process model quality. I anticipate that, based on this research, theories can be developed that facilitate the evaluation of the ’goodness’ of a business process model.

  3. Effect of 5E Teaching Model on Student Teachers' Understanding of Weightlessness

    Science.gov (United States)

    Tural, Guner; Akdeniz, Ali Riza; Alev, Nedim

    2010-01-01

    Weight is one of the basic concepts of physics. Its gravitational definition accommodates difficulties for students to understand the state of weightlessness. The aim of this study is to investigate the effect of materials based on 5E teaching model and related to weightlessness on science student teachers' learning. The sample of the study was 9…

  4. Understanding Challenges Physics Teachers Come Across as They Implement Learner-Centred Approaches in Lesotho

    Science.gov (United States)

    Qhobela, Makomosela; Moru, Eunice Kolitsoe

    2014-01-01

    Teacher-centred strategies have dominated most physics lessons in Lesotho. This study attempted to understand the contributing factors for the choice of teacher-centred teaching instead of learner-centred teaching with the goal of informing a professional development programme designed to address this problem. The paper responds to the research…

  5. Computational models in physics teaching: a framework

    Directory of Open Access Journals (Sweden)

    Marco Antonio Moreira

    2012-08-01

    Full Text Available The purpose of the present paper is to present a theoretical framework to promote and assist meaningful physics learning through computational models. Our proposal is based on the use of a tool, the AVM diagram, to design educational activities involving modeling and computer simulations. The idea is to provide a starting point for the construction and implementation of didactical approaches grounded in a coherent epistemological view about scientific modeling.

  6. Simplified Models for LHC New Physics Searches

    International Nuclear Information System (INIS)

    Alves, Daniele; Arkani-Hamed, Nima; Arora, Sanjay; Bai, Yang; Baumgart, Matthew; Berger, Joshua; Butler, Bart; Chang, Spencer; Cheng, Hsin-Chia; Cheung, Clifford; Chivukula, R. Sekhar; Cho, Won Sang; Cotta, Randy; D'Alfonso, Mariarosaria; El Hedri, Sonia; Essig, Rouven; Fitzpatrick, Liam; Fox, Patrick; Franceschini, Roberto

    2012-01-01

    This document proposes a collection of simplified models relevant to the design of new-physics searches at the LHC and the characterization of their results. Both ATLAS and CMS have already presented some results in terms of simplified models, and we encourage them to continue and expand this effort, which supplements both signature-based results and benchmark model interpretations. A simplified model is defined by an effective Lagrangian describing the interactions of a small number of new particles. Simplified models can equally well be described by a small number of masses and cross-sections. These parameters are directly related to collider physics observables, making simplified models a particularly effective framework for evaluating searches and a useful starting point for characterizing positive signals of new physics. This document serves as an official summary of the results from the 'Topologies for Early LHC Searches' workshop, held at SLAC in September of 2010, the purpose of which was to develop a set of representative models that can be used to cover all relevant phase space in experimental searches. Particular emphasis is placed on searches relevant for the first ∼ 50-500 pb -1 of data and those motivated by supersymmetric models. This note largely summarizes material posted at http://lhcnewphysics.org/, which includes simplified model definitions, Monte Carlo material, and supporting contacts within the theory community. We also comment on future developments that may be useful as more data is gathered and analyzed by the experiments.

  7. Simplified Models for LHC New Physics Searches

    Energy Technology Data Exchange (ETDEWEB)

    Alves, Daniele; /SLAC; Arkani-Hamed, Nima; /Princeton, Inst. Advanced Study; Arora, Sanjay; /Rutgers U., Piscataway; Bai, Yang; /SLAC; Baumgart, Matthew; /Johns Hopkins U.; Berger, Joshua; /Cornell U., Phys. Dept.; Buckley, Matthew; /Fermilab; Butler, Bart; /SLAC; Chang, Spencer; /Oregon U. /UC, Davis; Cheng, Hsin-Chia; /UC, Davis; Cheung, Clifford; /UC, Berkeley; Chivukula, R.Sekhar; /Michigan State U.; Cho, Won Sang; /Tokyo U.; Cotta, Randy; /SLAC; D' Alfonso, Mariarosaria; /UC, Santa Barbara; El Hedri, Sonia; /SLAC; Essig, Rouven, (ed.); /SLAC; Evans, Jared A.; /UC, Davis; Fitzpatrick, Liam; /Boston U.; Fox, Patrick; /Fermilab; Franceschini, Roberto; /LPHE, Lausanne /Pittsburgh U. /Argonne /Northwestern U. /Rutgers U., Piscataway /Rutgers U., Piscataway /Carleton U. /CERN /UC, Davis /Wisconsin U., Madison /SLAC /SLAC /SLAC /Rutgers U., Piscataway /Syracuse U. /SLAC /SLAC /Boston U. /Rutgers U., Piscataway /Seoul Natl. U. /Tohoku U. /UC, Santa Barbara /Korea Inst. Advanced Study, Seoul /Harvard U., Phys. Dept. /Michigan U. /Wisconsin U., Madison /Princeton U. /UC, Santa Barbara /Wisconsin U., Madison /Michigan U. /UC, Davis /SUNY, Stony Brook /TRIUMF; /more authors..

    2012-06-01

    This document proposes a collection of simplified models relevant to the design of new-physics searches at the LHC and the characterization of their results. Both ATLAS and CMS have already presented some results in terms of simplified models, and we encourage them to continue and expand this effort, which supplements both signature-based results and benchmark model interpretations. A simplified model is defined by an effective Lagrangian describing the interactions of a small number of new particles. Simplified models can equally well be described by a small number of masses and cross-sections. These parameters are directly related to collider physics observables, making simplified models a particularly effective framework for evaluating searches and a useful starting point for characterizing positive signals of new physics. This document serves as an official summary of the results from the 'Topologies for Early LHC Searches' workshop, held at SLAC in September of 2010, the purpose of which was to develop a set of representative models that can be used to cover all relevant phase space in experimental searches. Particular emphasis is placed on searches relevant for the first {approx} 50-500 pb{sup -1} of data and those motivated by supersymmetric models. This note largely summarizes material posted at http://lhcnewphysics.org/, which includes simplified model definitions, Monte Carlo material, and supporting contacts within the theory community. We also comment on future developments that may be useful as more data is gathered and analyzed by the experiments.

  8. PHYSICAL EDUCATION - PHYSICAL CULTURE. TWO MODELS, TWO DIDACTIC

    Directory of Open Access Journals (Sweden)

    Manuel Vizuete Carrizosa

    2014-11-01

    The survival of these conflicting positions and their interests and different views on education, in a lengthy space of time, as a consequence threw two teaching approaches and two different educational models, in which the objectives and content of education differ , and with them the forms and methods of teaching. The need to define the cultural and educational approach, in every time and place, is now a pressing need and challenge the processes of teacher training, as responsible for shaping an advanced physical education, adjusted to the time and place, the interests and needs of citizens and the democratic values of modern society.

  9. Composing Models of Geographic Physical Processes

    Science.gov (United States)

    Hofer, Barbara; Frank, Andrew U.

    Processes are central for geographic information science; yet geographic information systems (GIS) lack capabilities to represent process related information. A prerequisite to including processes in GIS software is a general method to describe geographic processes independently of application disciplines. This paper presents such a method, namely a process description language. The vocabulary of the process description language is derived formally from mathematical models. Physical processes in geography can be described in two equivalent languages: partial differential equations or partial difference equations, where the latter can be shown graphically and used as a method for application specialists to enter their process models. The vocabulary of the process description language comprises components for describing the general behavior of prototypical geographic physical processes. These process components can be composed by basic models of geographic physical processes, which is shown by means of an example.

  10. Task-specific visual cues for improving process model understanding

    NARCIS (Netherlands)

    Petrusel, Razvan; Mendling, Jan; Reijers, Hajo A.

    2016-01-01

    Context Business process models support various stakeholders in managing business processes and designing process-aware information systems. In order to make effective use of these models, they have to be readily understandable. Objective Prior research has emphasized the potential of visual cues to

  11. Using Supply, Demand, and the Cournot Model to Understand Corruption

    Science.gov (United States)

    Hayford, Marc D.

    2007-01-01

    The author combines the supply and demand model of taxes with a Cournot model of bribe takers to develop a simple and useful framework for understanding the effect of corruption on economic activity. There are many examples of corruption in both developed and developing countries. Because corruption decreases the level of economic activity and…

  12. PHYSICAL EDUCATION - PHYSICAL CULTURE. TWO MODELS, TWO DIDACTIC

    Directory of Open Access Journals (Sweden)

    Manuel Vizuete Carrizosa

    2014-10-01

    Full Text Available Physical Education is currently facing a number of problems that are rooted in the identity crisis prompted by the spread of the professional group, the confrontation of ideas from the scientific community and the competing interests of different political and social areas, compared to which physical education has failed, or unable, to react in time. The political and ideological confrontation that characterized the twentieth century gave us two forms, each with a consistent ideological position, in which the body as a subject of education was understood from two different positions: one set from the left and communism and another, from Western democratic societies.The survival of these conflicting positions and their interests and different views on education, in a lengthy space of time, as a consequence threw two teaching approaches and two different educational models, in which the objectives and content of education differ , and with them the forms and methods of teaching. The need to define the cultural and educational approach, in every time and place, is now a pressing need and challenge the processes of teacher training, as responsible for shaping an advanced physical education, adjusted to the time and place, the interests and needs of citizens and the democratic values of modern society.

  13. Self-determination theory and understanding of student motivation in physical education instruction

    Directory of Open Access Journals (Sweden)

    Đorđić Višnja

    2010-01-01

    Full Text Available Physical education is considered to be a favorable context for accomplishment of important educational outcomes and promotion of physical activity in children and youth. The real scope of physical education instruction largely depends on student motivation. Self-determination theory, as a specific macrotheory of motivation, offers a rewarding framework for understanding student motivation in physical education instruction. The paper presents the basic tenets of self-determination theory, the most important studies in the domain of physical education and didactic and methodical implications. Two mini-theories within the self-determination theory are analyzed in more detail, the cognitive evaluation theory and the organismic integration theory. Empirical verification of the theoretical tenets indicates the existence of typical motivational profiles of students in physical education instruction, the basic psychological needs as mediators of influence of social and interpersonal factors on student motivation, followed by the importance of motivational climate, students' goal orientations and teaching style for self-determination of students' behavior in physical education instruction. Didactic and methodical implications refer to the need for developing a more flexible curriculum of physical education, encouraging a motivational climate, task-focused goal orientations, and, especially, encouraging the perceived moving competence of the student.

  14. Using Learning Analytics to Understand Scientific Modeling in the Classroom

    Directory of Open Access Journals (Sweden)

    David Quigley

    2017-11-01

    Full Text Available Scientific models represent ideas, processes, and phenomena by describing important components, characteristics, and interactions. Models are constructed across various scientific disciplines, such as the food web in biology, the water cycle in Earth science, or the structure of the solar system in astronomy. Models are central for scientists to understand phenomena, construct explanations, and communicate theories. Constructing and using models to explain scientific phenomena is also an essential practice in contemporary science classrooms. Our research explores new techniques for understanding scientific modeling and engagement with modeling practices. We work with students in secondary biology classrooms as they use a web-based software tool—EcoSurvey—to characterize organisms and their interrelationships found in their local ecosystem. We use learning analytics and machine learning techniques to answer the following questions: (1 How can we automatically measure the extent to which students’ scientific models support complete explanations of phenomena? (2 How does the design of student modeling tools influence the complexity and completeness of students’ models? (3 How do clickstreams reflect and differentiate student engagement with modeling practices? We analyzed EcoSurvey usage data collected from two different deployments with over 1,000 secondary students across a large urban school district. We observe large variations in the completeness and complexity of student models, and large variations in their iterative refinement processes. These differences reveal that certain key model features are highly predictive of other aspects of the model. We also observe large differences in student modeling practices across different classrooms and teachers. We can predict a student’s teacher based on the observed modeling practices with a high degree of accuracy without significant tuning of the predictive model. These results highlight

  15. Physical models for high burnup fuel

    International Nuclear Information System (INIS)

    Kanyukova, V.; Khoruzhii, O.; Likhanskii, V.; Solodovnikov, G.; Sorokin, A.

    2003-01-01

    In this paper some models of processes in high burnup fuel developed in Src of Russia Troitsk Institute for Innovation and Fusion Research are presented. The emphasis is on the description of the degradation of the fuel heat conductivity, radial profiles of the burnup and the plutonium accumulation, restructuring of the pellet rim, mechanical pellet-cladding interaction. The results demonstrate the possibility of rather accurate description of the behaviour of the fuel of high burnup on the base of simplified models in frame of the fuel performance code if the models are physically ground. The development of such models requires the performance of the detailed physical analysis to serve as a test for a correct choice of allowable simplifications. This approach was applied in the SRC of Russia TRINITI to develop a set of models for the WWER fuel resulting in high reliability of predictions in simulation of the high burnup fuel

  16. The optical model in atomic physics

    International Nuclear Information System (INIS)

    McCarthy, I.E.

    1978-01-01

    The optical model for electron scattering on atoms has quite a short history in comparison with nuclear physics. The main reason for this is that there were insufficient data. Angular distribution for elastic and some inelastic scattering have now been measured for the atoms which exist in gaseous form at reasonable temperatures, inert gases, hydrogen, alkalies and mercury being the main ones out in. The author shows that the optical model makes sense in atomic physics by considering its theory and recent history. (orig./AH) [de

  17. Characterizing, modeling, and addressing gender disparities in introductory college physics

    Science.gov (United States)

    Kost-Smith, Lauren Elizabeth

    2011-12-01

    The underrepresentation and underperformance of females in physics has been well documented and has long concerned policy-makers, educators, and the physics community. In this thesis, we focus on gender disparities in the first- and second-semester introductory, calculus-based physics courses at the University of Colorado. Success in these courses is critical for future study and careers in physics (and other sciences). Using data gathered from roughly 10,000 undergraduate students, we identify and model gender differences in the introductory physics courses in three areas: student performance, retention, and psychological factors. We observe gender differences on several measures in the introductory physics courses: females are less likely to take a high school physics course than males and have lower standardized mathematics test scores; males outscore females on both pre- and post-course conceptual physics surveys and in-class exams; and males have more expert-like attitudes and beliefs about physics than females. These background differences of males and females account for 60% to 70% of the gender gap that we observe on a post-course survey of conceptual physics understanding. In analyzing underlying psychological factors of learning, we find that female students report lower self-confidence related to succeeding in the introductory courses (self-efficacy) and are less likely to report seeing themselves as a "physics person". Students' self-efficacy beliefs are significant predictors of their performance, even when measures of physics and mathematics background are controlled, and account for an additional 10% of the gender gap. Informed by results from these studies, we implemented and tested a psychological, self-affirmation intervention aimed at enhancing female students' performance in Physics 1. Self-affirmation reduced the gender gap in performance on both in-class exams and the post-course conceptual physics survey. Further, the benefit of the self

  18. Understanding Surface Adhesion in Nature: A Peeling Model.

    Science.gov (United States)

    Gu, Zhen; Li, Siheng; Zhang, Feilong; Wang, Shutao

    2016-07-01

    Nature often exhibits various interesting and unique adhesive surfaces. The attempt to understand the natural adhesion phenomena can continuously guide the design of artificial adhesive surfaces by proposing simplified models of surface adhesion. Among those models, a peeling model can often effectively reflect the adhesive property between two surfaces during their attachment and detachment processes. In the context, this review summarizes the recent advances about the peeling model in understanding unique adhesive properties on natural and artificial surfaces. It mainly includes four parts: a brief introduction to natural surface adhesion, the theoretical basis and progress of the peeling model, application of the peeling model, and finally, conclusions. It is believed that this review is helpful to various fields, such as surface engineering, biomedicine, microelectronics, and so on.

  19. Plasma simulation studies using multilevel physics models

    International Nuclear Information System (INIS)

    Park, W.; Belova, E.V.; Fu, G.Y.

    2000-01-01

    The question of how to proceed toward ever more realistic plasma simulation studies using ever increasing computing power is addressed. The answer presented here is the M3D (Multilevel 3D) project, which has developed a code package with a hierarchy of physics levels that resolve increasingly complete subsets of phase-spaces and are thus increasingly more realistic. The rationale for the multilevel physics models is given. Each physics level is described and examples of its application are given. The existing physics levels are fluid models (3D configuration space), namely magnetohydrodynamic (MHD) and two-fluids; and hybrid models, namely gyrokinetic-energetic-particle/MHD (5D energetic particle phase-space), gyrokinetic-particle-ion/fluid-electron (5D ion phase-space), and full-kinetic-particle-ion/fluid-electron level (6D ion phase-space). Resolving electron phase-space (5D or 6D) remains a future project. Phase-space-fluid models are not used in favor of delta f particle models. A practical and accurate nonlinear fluid closure for noncollisional plasmas seems not likely in the near future

  20. A Model of Designing: Understanding Engineering Design Activity

    DEFF Research Database (Denmark)

    Ahmed, Saeema; Aurisicchio, Marco

    2007-01-01

    This research describes an understanding of design activity through design questions. From a number of previous studies two types of questions have been identified: 1) reasoning questions; and 2) strategic questions. Strategic questions are part of an experienced designers approach to solving a d...... solving model. An example of aerospace engineering design is used to illustrate the argument. The research contributes to an understanding of design activity....

  1. A validated physical model of greenhouse climate

    International Nuclear Information System (INIS)

    Bot, G.P.A.

    1989-01-01

    In the greenhouse model the momentaneous environmental crop growth factors are calculated as output, together with the physical behaviour of the crop. The boundary conditions for this model are the outside weather conditions; other inputs are the physical characteristics of the crop, of the greenhouse and of the control system. The greenhouse model is based on the energy, water vapour and CO 2 balances of the crop-greenhouse system. While the emphasis is on the dynamic behaviour of the greenhouse for implementation in continuous optimization, the state variables temperature, water vapour pressure and carbondioxide concentration in the relevant greenhouse parts crop, air, soil and cover are calculated from the balances over these parts. To do this in a proper way, the physical exchange processes between the system parts have to be quantified first. Therefore the greenhouse model is constructed from submodels describing these processes: a. Radiation transmission model for the modification of the outside to the inside global radiation. b. Ventilation model to describe the ventilation exchange between greenhouse and outside air. c. The description of the exchange of energy and mass between the crop and the greenhouse air. d. Calculation of the thermal radiation exchange between the various greenhouse parts. e. Quantification of the convective exchange processes between the greenhouse air and respectively the cover, the heating pipes and the soil surface and between the cover and the outside air. f. Determination of the heat conduction in the soil. The various submodels are validated first and then the complete greenhouse model is verified

  2. Topos models for physics and topos theory

    International Nuclear Information System (INIS)

    Wolters, Sander

    2014-01-01

    What is the role of topos theory in the topos models for quantum theory as used by Isham, Butterfield, Döring, Heunen, Landsman, Spitters, and others? In other words, what is the interplay between physical motivation for the models and the mathematical framework used in these models? Concretely, we show that the presheaf topos model of Butterfield, Isham, and Döring resembles classical physics when viewed from the internal language of the presheaf topos, similar to the copresheaf topos model of Heunen, Landsman, and Spitters. Both the presheaf and copresheaf models provide a “quantum logic” in the form of a complete Heyting algebra. Although these algebras are natural from a topos theoretic stance, we seek a physical interpretation for the logical operations. Finally, we investigate dynamics. In particular, we describe how an automorphism on the operator algebra induces a homeomorphism (or isomorphism of locales) on the associated state spaces of the topos models, and how elementary propositions and truth values transform under the action of this homeomorphism. Also with dynamics the focus is on the internal perspective of the topos

  3. An image-based approach to understanding the physics of MR artifacts.

    Science.gov (United States)

    Morelli, John N; Runge, Val M; Ai, Fei; Attenberger, Ulrike; Vu, Lan; Schmeets, Stuart H; Nitz, Wolfgang R; Kirsch, John E

    2011-01-01

    As clinical magnetic resonance (MR) imaging becomes more versatile and more complex, it is increasingly difficult to develop and maintain a thorough understanding of the physical principles that govern the changing technology. This is particularly true for practicing radiologists, whose primary obligation is to interpret clinical images and not necessarily to understand complex equations describing the underlying physics. Nevertheless, the physics of MR imaging plays an important role in clinical practice because it determines image quality, and suboptimal image quality may hinder accurate diagnosis. This article provides an image-based explanation of the physics underlying common MR imaging artifacts, offering simple solutions for remedying each type of artifact. Solutions that have emerged from recent technologic advances with which radiologists may not yet be familiar are described in detail. Types of artifacts discussed include those resulting from voluntary and involuntary patient motion, magnetic susceptibility, magnetic field inhomogeneities, gradient nonlinearity, standing waves, aliasing, chemical shift, and signal truncation. With an improved awareness and understanding of these artifacts, radiologists will be better able to modify MR imaging protocols so as to optimize clinical image quality, allowing greater confidence in diagnosis. Copyright © RSNA, 2011.

  4. We need more empirical investigations and model validation for a better understanding of crime. Comment on "Statistical physics of crime: A review" by M.R. D'Orsogna and M. Perc

    Science.gov (United States)

    Ribeiro, Haroldo V.

    2015-03-01

    Since the seminal works of Wilson and Kelling [1] in 1982, the "broken windows theory" seems to have been widely accepted among the criminologists and, in fact, empirical findings actually point out that criminals tend to return to previously visited locations. Crime has always been part of the urban society's agenda and has also attracted the attention of scholars from social sciences ever since. Furthermore, over the past six decades the world has experienced a quick and notorious urbanization process: by the eighties the urban population was about 40% of total population, and today more than half (54%) of the world population is urban [2]. The urbanization has brought us many benefits such as better working opportunities and health care, but has also created several problems such as pollution and a considerable rise in the criminal activities. In this context of urban problems, crime deserves a special attention because there is a huge necessity of empirical and mathematical (modeling) investigations which, apart from the natural academic interest, may find direct implications for the organization of our society by improving political decisions and resource allocation.

  5. Ladder physics in the spin fermion model

    International Nuclear Information System (INIS)

    Tsvelik, A. M.

    2017-01-01

    A link is established between the spin fermion (SF) model of the cuprates and the approach based on the analogy between the physics of doped Mott insulators in two dimensions and the physics of fermionic ladders. This enables one to use nonperturbative results derived for fermionic ladders to move beyond the large-N approximation in the SF model. Here, it is shown that the paramagnon exchange postulated in the SF model has exactly the right form to facilitate the emergence of the fully gapped d-Mott state in the region of the Brillouin zone at the hot spots of the Fermi surface. Hence, the SF model provides an adequate description of the pseudogap.

  6. Statistical physics of pairwise probability models

    DEFF Research Database (Denmark)

    Roudi, Yasser; Aurell, Erik; Hertz, John

    2009-01-01

    (dansk abstrakt findes ikke) Statistical models for describing the probability distribution over the states of biological systems are commonly used for dimensional reduction. Among these models, pairwise models are very attractive in part because they can be fit using a reasonable amount of  data......: knowledge of the means and correlations between pairs of elements in the system is sufficient. Not surprisingly, then, using pairwise models for studying neural data has been the focus of many studies in recent years. In this paper, we describe how tools from statistical physics can be employed for studying...

  7. Simulation and similarity using models to understand the world

    CERN Document Server

    Weisberg, Michael

    2013-01-01

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

  8. Diagnosing Students' Understanding of the Nature of Models

    Science.gov (United States)

    Gogolin, Sarah; Krüger, Dirk

    2017-10-01

    Students' understanding of models in science has been subject to a number of investigations. The instruments the researchers used are suitable for educational research but, due to their complexity, cannot be employed directly by teachers. This article presents forced choice (FC) tasks, which, assembled as a diagnostic instrument, are supposed to measure students' understanding of the nature of models efficiently, while being sensitive enough to detect differences between individuals. In order to evaluate if the diagnostic instrument is suitable for its intended use, we propose an approach that complies with the demand to integrate students' responses to the tasks into the validation process. Evidence for validity was gathered based on relations to other variables and on students' response processes. Students' understanding of the nature of models was assessed using three methods: FC tasks, open-ended tasks and interviews ( N = 448). Furthermore, concurrent think-aloud protocols ( N = 30) were performed. The results suggest that the method and the age of the students have an effect on their understanding of the nature of models. A good understanding of the FC tasks as well as a convergence in the findings across the three methods was documented for grades eleven and twelve. This indicates that teachers can use the diagnostic instrument for an efficient and, at the same time, valid diagnosis for this group. Finally, the findings of this article may provide a possible explanation for alternative findings from previous studies as a result of specific methods that were used.

  9. Physical and numerical modeling of Joule-heated melters

    Energy Technology Data Exchange (ETDEWEB)

    Eyler, L.L.; Skarda, R.J.; Crowder, R.S. III; Trent, D.S.; Reid, C.R.; Lessor, D.L.

    1985-10-01

    The Joule-heated ceramic-lined melter is an integral part of the high level waste immobilization process under development by the US Department of Energy. Scaleup and design of this waste glass melting furnace requires an understanding of the relationships between melting cavity design parameters and the furnace performance characteristics such as mixing, heat transfer, and electrical requirements. Developing empirical models of these relationships through actual melter testing with numerous designs would be a very costly and time consuming task. Additionally, the Pacific Northwest Laboratory (PNL) has been developing numerical models that simulate a Joule-heated melter for analyzing melter performance. This report documents the method used and results of this modeling effort. Numerical modeling results are compared with the more conventional, physical modeling results to validate the approach. Also included are the results of numerically simulating an operating research melter at PNL. Physical Joule-heated melters modeling results used for qualiying the simulation capabilities of the melter code included: (1) a melter with a single pair of electrodes and (2) a melter with a dual pair (two pairs) of electrodes. The physical model of the melter having two electrode pairs utilized a configuration with primary and secondary electrodes. The principal melter parameters (the ratio of power applied to each electrode pair, modeling fluid depth, electrode spacing) were varied in nine tests of the physical model during FY85. Code predictions were made for five of these tests. Voltage drops, temperature field data, and electric field data varied in their agreement with the physical modeling results, but in general were judged acceptable. 14 refs., 79 figs., 17 tabs.

  10. Physical and numerical modeling of Joule-heated melters

    International Nuclear Information System (INIS)

    Eyler, L.L.; Skarda, R.J.; Crowder, R.S. III; Trent, D.S.; Reid, C.R.; Lessor, D.L.

    1985-10-01

    The Joule-heated ceramic-lined melter is an integral part of the high level waste immobilization process under development by the US Department of Energy. Scaleup and design of this waste glass melting furnace requires an understanding of the relationships between melting cavity design parameters and the furnace performance characteristics such as mixing, heat transfer, and electrical requirements. Developing empirical models of these relationships through actual melter testing with numerous designs would be a very costly and time consuming task. Additionally, the Pacific Northwest Laboratory (PNL) has been developing numerical models that simulate a Joule-heated melter for analyzing melter performance. This report documents the method used and results of this modeling effort. Numerical modeling results are compared with the more conventional, physical modeling results to validate the approach. Also included are the results of numerically simulating an operating research melter at PNL. Physical Joule-heated melters modeling results used for qualiying the simulation capabilities of the melter code included: (1) a melter with a single pair of electrodes and (2) a melter with a dual pair (two pairs) of electrodes. The physical model of the melter having two electrode pairs utilized a configuration with primary and secondary electrodes. The principal melter parameters (the ratio of power applied to each electrode pair, modeling fluid depth, electrode spacing) were varied in nine tests of the physical model during FY85. Code predictions were made for five of these tests. Voltage drops, temperature field data, and electric field data varied in their agreement with the physical modeling results, but in general were judged acceptable. 14 refs., 79 figs., 17 tabs

  11. Mathematical and physical models and radiobiology

    International Nuclear Information System (INIS)

    Lokajicek, M.

    1980-01-01

    The hit theory of the mechanism of biological radiation effects in the cell is discussed with respect to radiotherapy. The mechanisms of biological effects and of intracellular recovery, the cumulative radiation effect and the cumulative biological effect in fractionated irradiation are described. The benefit is shown of consistent application of mathematical and physical models in radiobiology and radiotherapy. (J.P.)

  12. Protein Folding: Search for Basic Physical Models

    Directory of Open Access Journals (Sweden)

    Ivan Y. Torshin

    2003-01-01

    Full Text Available How a unique three-dimensional structure is rapidly formed from the linear sequence of a polypeptide is one of the important questions in contemporary science. Apart from biological context of in vivo protein folding (which has been studied only for a few proteins, the roles of the fundamental physical forces in the in vitro folding remain largely unstudied. Despite a degree of success in using descriptions based on statistical and/or thermodynamic approaches, few of the current models explicitly include more basic physical forces (such as electrostatics and Van Der Waals forces. Moreover, the present-day models rarely take into account that the protein folding is, essentially, a rapid process that produces a highly specific architecture. This review considers several physical models that may provide more direct links between sequence and tertiary structure in terms of the physical forces. In particular, elaboration of such simple models is likely to produce extremely effective computational techniques with value for modern genomics.

  13. Dilution physics modeling: Dissolution/precipitation chemistry

    International Nuclear Information System (INIS)

    Onishi, Y.; Reid, H.C.; Trent, D.S.

    1995-09-01

    This report documents progress made to date on integrating dilution/precipitation chemistry and new physical models into the TEMPEST thermal-hydraulics computer code. Implementation of dissolution/precipitation chemistry models is necessary for predicting nonhomogeneous, time-dependent, physical/chemical behavior of tank wastes with and without a variety of possible engineered remediation and mitigation activities. Such behavior includes chemical reactions, gas retention, solids resuspension, solids dissolution and generation, solids settling/rising, and convective motion of physical and chemical species. Thus this model development is important from the standpoint of predicting the consequences of various engineered activities, such as mitigation by dilution, retrieval, or pretreatment, that can affect safe operations. The integration of a dissolution/precipitation chemistry module allows the various phase species concentrations to enter into the physical calculations that affect the TEMPEST hydrodynamic flow calculations. The yield strength model of non-Newtonian sludge correlates yield to a power function of solids concentration. Likewise, shear stress is concentration-dependent, and the dissolution/precipitation chemistry calculations develop the species concentration evolution that produces fluid flow resistance changes. Dilution of waste with pure water, molar concentrations of sodium hydroxide, and other chemical streams can be analyzed for the reactive species changes and hydrodynamic flow characteristics

  14. Physical and mathematical modelling of extrusion processes

    DEFF Research Database (Denmark)

    Arentoft, Mogens; Gronostajski, Z.; Niechajowics, A.

    2000-01-01

    The main objective of the work is to study the extrusion process using physical modelling and to compare the findings of the study with finite element predictions. The possibilities and advantages of the simultaneous application of both of these methods for the analysis of metal forming processes...

  15. Particle modeling of plasmas computational plasma physics

    International Nuclear Information System (INIS)

    Dawson, J.M.

    1991-01-01

    Recently, through the development of supercomputers, a powerful new method for exploring plasmas has emerged; it is computer modeling of plasmas. Such modeling can duplicate many of the complex processes that go on in a plasma and allow scientists to understand what the important processes are. It helps scientists gain an intuition about this complex state of matter. It allows scientists and engineers to explore new ideas on how to use plasma before building costly experiments; it allows them to determine if they are on the right track. It can duplicate the operation of devices and thus reduce the need to build complex and expensive devices for research and development. This is an exciting new endeavor that is in its infancy, but which can play an important role in the scientific and technological competitiveness of the US. There are a wide range of plasma models that are in use. There are particle models, fluid models, hybrid particle fluid models. These can come in many forms, such as explicit models, implicit models, reduced dimensional models, electrostatic models, magnetostatic models, electromagnetic models, and almost an endless variety of other models. Here the author will only discuss particle models. He will give a few examples of the use of such models; these will be taken from work done by the Plasma Modeling Group at UCLA because he is most familiar with work. However, it only gives a small view of the wide range of work being done around the US, or for that matter around the world

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

    DEFF Research Database (Denmark)

    Badie, Farshad

    2017-01-01

    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...... systems. In other words, it attempts to describe a theoretical model for concept understanding and to reflect the phenomenon of ‘concept understanding’ in terminological knowledge representation systems. Finally, it will design an ontology that schemes the structure of concept understanding based...

  17. A new model for understanding teamwork onboard: the shipmate model.

    Science.gov (United States)

    Espevik, Roar; Olsen, Olav Kjellevold

    2013-01-01

    The increasing complexity onboard a ship underline the importance of crews that are able to coordinate and cooperate with each other to facilitate task objectives through a shared understanding of resources (e.g. team members' knowledge, skills and experience), the crew's goals, and the constrains under which they work. Rotation of personnel through 24/7 shift-work schedules and replacements often put crews ina position of having little or no previous history as a team. Findings from 3 studies indicated that unfamiliar teams used less efficient coordination strategies which reduced efficiency and increased levels of stress in situations where team members where experts on task, distributed or unknown to task and environment.Implications for staffing, safety and training are discussed.

  18. Developing and validating a conceptual survey to assess introductory physics students’ understanding of magnetism

    Science.gov (United States)

    Li, Jing; Singh, Chandralekha

    2017-03-01

    Development of validated physics surveys on various topics is important for investigating the extent to which students master those concepts after traditional instruction and for assessing innovative curricula and pedagogies that can improve student understanding significantly. Here, we discuss the development and validation of a conceptual multiple-choice survey related to magnetism suitable for introductory physics courses. The survey was developed taking into account common students’ difficulties with magnetism concepts covered in introductory physics courses found in our investigation and the incorrect choices to the multiple-choice questions were designed based upon those common student difficulties. After the development and validation of the survey, it was administered to introductory physics students in various classes in paper-pencil format before and after traditional lecture-based instruction in relevant concepts. We compared the performance of students on the survey in the algebra-based and calculus-based introductory physics courses before and after traditional lecture-based instruction in relevant magnetism concepts. We discuss the common difficulties of introductory physics students with magnetism concepts we found via the survey. We also administered the survey to upper-level undergraduates majoring in physics and PhD students to benchmark the survey and compared their performance with those of traditionally taught introductory physics students for whom the survey is intended. A comparison with the base line data on the validated magnetism survey from traditionally taught introductory physics courses and upper-level undergraduate and PhD students discussed in this paper can help instructors assess the effectiveness of curricula and pedagogies which is especially designed to help students integrate conceptual and quantitative understanding and develop a good grasp of the concepts. In particular, if introductory physics students’ average

  19. Developing and validating a conceptual survey to assess introductory physics students’ understanding of magnetism

    International Nuclear Information System (INIS)

    Li, Jing; Singh, Chandralekha

    2017-01-01

    Development of validated physics surveys on various topics is important for investigating the extent to which students master those concepts after traditional instruction and for assessing innovative curricula and pedagogies that can improve student understanding significantly. Here, we discuss the development and validation of a conceptual multiple-choice survey related to magnetism suitable for introductory physics courses. The survey was developed taking into account common students’ difficulties with magnetism concepts covered in introductory physics courses found in our investigation and the incorrect choices to the multiple-choice questions were designed based upon those common student difficulties. After the development and validation of the survey, it was administered to introductory physics students in various classes in paper–pencil format before and after traditional lecture-based instruction in relevant concepts. We compared the performance of students on the survey in the algebra-based and calculus-based introductory physics courses before and after traditional lecture-based instruction in relevant magnetism concepts. We discuss the common difficulties of introductory physics students with magnetism concepts we found via the survey. We also administered the survey to upper-level undergraduates majoring in physics and PhD students to benchmark the survey and compared their performance with those of traditionally taught introductory physics students for whom the survey is intended. A comparison with the base line data on the validated magnetism survey from traditionally taught introductory physics courses and upper-level undergraduate and PhD students discussed in this paper can help instructors assess the effectiveness of curricula and pedagogies which is especially designed to help students integrate conceptual and quantitative understanding and develop a good grasp of the concepts. In particular, if introductory physics students’ average

  20. Service Learning In Physics: The Consultant Model

    Science.gov (United States)

    Guerra, David

    2005-04-01

    Each year thousands of students across the country and across the academic disciplines participate in service learning. Unfortunately, with no clear model for integrating community service into the physics curriculum, there are very few physics students engaged in service learning. To overcome this shortfall, a consultant based service-learning program has been developed and successfully implemented at Saint Anselm College (SAC). As consultants, students in upper level physics courses apply their problem solving skills in the service of others. Most recently, SAC students provided technical and managerial support to a group from Girl's Inc., a national empowerment program for girls in high-risk, underserved areas, who were participating in the national FIRST Lego League Robotics competition. In their role as consultants the SAC students provided technical information through brainstorming sessions and helped the girls stay on task with project management techniques, like milestone charting. This consultant model of service-learning, provides technical support to groups that may not have a great deal of resources and gives physics students a way to improve their interpersonal skills, test their technical expertise, and better define the marketable skill set they are developing through the physics curriculum.

  1. Nuclear physics for applications. A model approach

    International Nuclear Information System (INIS)

    Prussin, S.G.

    2007-01-01

    Written by a researcher and teacher with experience at top institutes in the US and Europe, this textbook provides advanced undergraduates minoring in physics with working knowledge of the principles of nuclear physics. Simplifying models and approaches reveal the essence of the principles involved, with the mathematical and quantum mechanical background integrated in the text where it is needed and not relegated to the appendices. The practicality of the book is enhanced by numerous end-of-chapter problems and solutions available on the Wiley homepage. (orig.)

  2. Race to improve student understanding of uncertainty: Using LEGO race cars in the physics lab

    Science.gov (United States)

    Parappilly, Maria; Hassam, Christopher; Woodman, Richard J.

    2018-01-01

    Laboratories using LEGO race cars were developed for students in an introductory physics topic with a high early drop-out rate. In a 2014 pilot study, the labs were offered to improve students' confidence with experiments and laboratory skills, especially uncertainty propagation. This intervention was extended into the intro level physics topic the next year, for comparison and evaluation. Considering the pilot study, we subsequently adapted the delivery of the LEGO labs for a large Engineering Mechanics cohort. A qualitative survey of the students was taken to gain insight into their perception of the incorporation of LEGO race cars into physics labs. For Engineering, the findings show that LEGO physics was instrumental in teaching students the measurement and uncertainty, improving their lab reporting skills, and was a key factor in reducing the early attrition rate. This paper briefly recalls the results of the pilot study, and how variations in the delivery yielded better learning outcomes. A novel method is proposed for how LEGO race cars in a physics lab can help students increase their understanding of uncertainty and motivate them towards physics practicals.

  3. Same-sex attraction: a model to aid nurses' understanding.

    Science.gov (United States)

    Richardson, Brian

    2009-12-01

    Young people attracted to people of their own sex are at risk of bullying and discrimination. It is often difficult for them to find support. Either emotionally or in relation to their health needs. This article explores a model to aid nurses in understanding the process individuals go through before coming to terms with their sexuality. The model also outlines the steps that nurses can take to enhance the care they provide for this vulnerable group of patients and clients.

  4. Prototyping of cerebral vasculature physical models.

    Science.gov (United States)

    Khan, Imad S; Kelly, Patrick D; Singer, Robert J

    2014-01-01

    Prototyping of cerebral vasculature models through stereolithographic methods have the ability to accurately depict the 3D structures of complicated aneurysms with high accuracy. We describe the method to manufacture such a model and review some of its uses in the context of treatment planning, research, and surgical training. We prospectively used the data from the rotational angiography of a 40-year-old female who presented with an unruptured right paraclinoid aneurysm. The 3D virtual model was then converted to a physical life-sized model. The model constructed was shown to be a very accurate depiction of the aneurysm and its associated vasculature. It was found to be useful, among other things, for surgical training and as a patient education tool. With improving and more widespread printing options, these models have the potential to become an important part of research and training modalities.

  5. WebCom: A Model for Understanding Web Site Communication

    DEFF Research Database (Denmark)

    Godsk, Mikkel; Petersen, Anja Bechmann

    2008-01-01

    of the approaches' strengths. Furthermore, it is discussed and shortly demonstrated how WebCom can be used for analytical and design purposes with YouTube as an example. The chapter concludes that WebCom is able to serve as a theoretically-based model for understanding complex Web site communication situations...

  6. Thinking Egyptian: Active Models for Understanding Spatial Representation.

    Science.gov (United States)

    Schiferl, Ellen

    This paper highlights how introductory textbooks on Egyptian art inhibit understanding by reinforcing student preconceptions, and demonstrates another approach to discussing space with a classroom exercise and software. The alternative approach, an active model for spatial representation, introduced here was developed by adapting classroom…

  7. A New Conceptual Model for Understanding International Students' College Needs

    Science.gov (United States)

    Alfattal, Eyad

    2016-01-01

    This study concerns the theory and practice of international marketing in higher education with the purpose of exploring a conceptual model for understanding international students' needs in the context of a four-year college in the United States. A transcendental phenomenological design was employed to investigate the essence of international…

  8. A self-determination theory approach to understanding the antecedents of teachers' motivational strategies in physical education.

    Science.gov (United States)

    Taylor, Ian M; Ntoumanis, Nikos; Standage, Martyn

    2008-02-01

    Physical education teachers can influence students' self-determination through the motivational strategies that they use. The current study examined how teachers' reported use of three motivational strategies (providing a meaningful rationale, providing instrumental help and support, and gaining an understanding of the students) were predicted by perceived job pressure, perceptions of student self-determination, the teachers' autonomous orientation, psychological need satisfaction, and self-determination to teach. Structural equation modeling supported a model in which perceived job pressure, perceptions of student self-determination, and teacher autonomous orientation predicted teacher psychological need satisfaction, which, in turn positively influenced teacher self-determination. The last positively predicted the use of all three strategies. Direct positive effects of teachers' psychological need satisfaction on the strategies of gaining an understanding of students and instrumental help and support were also found. In summary, factors that influence teacher motivation may also indirectly affect their motivational strategies toward students.

  9. “If I had to do it, then I would”: Understanding early middle school students’ perceptions of physics and physics-related careers by gender

    OpenAIRE

    Emily A. Dare; Gillian H. Roehrig

    2016-01-01

    [This paper is part of the Focused Collection on Gender in Physics.] This study examined the perceptions of 6th grade middle school students regarding physics and physics-related careers. The overarching goal of this work was to understand similarities and differences between girls’ and boys’ perceptions surrounding physics and physics-related careers as part of a long-term effort to increase female interest and representation in this particular field of science. A theoretical framework based...

  10. Students’ understanding and application of the area under the curve concept in physics problems

    Directory of Open Access Journals (Sweden)

    Dong-Hai Nguyen

    2011-06-01

    Full Text Available This study investigates how students understand and apply the area under the curve concept and the integral-area relation in solving introductory physics problems. We interviewed 20 students in the first semester and 15 students from the same cohort in the second semester of a calculus-based physics course sequence on several problems involving the area under the curve concept. We found that only a few students could recognize that the concept of area under the curve was applicable in physics problems. Even when students could invoke the area under the curve concept, they did not necessarily understand the relationship between the process of accumulation and the area under a curve, so they failed to apply it to novel situations. We also found that when presented with several graphs, students had difficulty in selecting the graph such that the area under the graph corresponded to a given integral, although all of them could state that “the integral equaled the area under the curve.” The findings in this study are consistent with those in previous mathematics education research and research in physics education on students’ use of the area under the curve.

  11. Noise stabilization effects in models of interdisciplinary physics

    International Nuclear Information System (INIS)

    Spagnolo, B; Augello, G; Caldara, P; Fiasconaro, A; La Cognata, A; Pizzolato, N; Valenti, D; Dubkov, A A; Pankratov, A L

    2009-01-01

    Metastability is a generic feature of many nonlinear systems, and the problem of the lifetime of metastable states involves fundamental aspects of nonequilibrium statistical mechanics. The investigation of noise-induced phenomena in far from equilibrium systems is one of the approaches used to understand the behaviour of physical and biological complex systems. The enhancement of the lifetime of metastable states through the noise enhanced stability effect and the role played by the resonant activation phenomenon will be discussed in models of interdisciplinary physics: (i) polymer translocation dynamics; (ii) transient regime of FitzHugh-Nagumo model; (iii) market stability in a nonlinear Heston model; (iv) dynamics of Josephson junctions; (v) metastability in a quantum bitable system.

  12. A cross-cultural, multilevel study of inquiry-based instruction effects on conceptual understanding and motivation in physics

    Science.gov (United States)

    Negishi, Meiko

    Student achievement and motivation to learn physics is highly valued in many industrialized countries including the United States and Japan. Science education curricula in these countries emphasize the importance and encourage classroom teachers to use an inquiry approach. This dissertation investigated high school students' motivational orientations and their understanding of physics concepts in a context of inquiry-based instruction. The goals were to explore the patterns of instructional effects on motivation and learning in each country and to examine cultural differences and similarities. Participants consisted of 108 students (55 females, 53 males) and 9 physics teachers in the United States and 616 students (203 females and 413 males) and 11 physics teachers in Japan. Students were administered (a) Force Concept Inventory measuring physics conceptual understanding and (b) Attitudes about Science Questionnaire measuring student motivational orientations. Teachers were given a survey regarding their use of inquiry teaching practices and background information. Additionally, three teachers in each country were interviewed and observed in their classrooms. For the data analysis, two-level hierarchical linear modeling (HLM) methods were used to examine individual student differences (i.e., learning, motivation, and gender) within each classroom (i.e., inquiry-based teaching, teaching experience, and class size) in the U.S. and Japan, separately. Descriptive statistical analyses were also conducted. The results indicated that there was a cultural similarity in that current teaching practices had minimal influence on conceptual understanding as well as motivation of high school students between the U.S. and Japan. In contrast, cultural differences were observed in classroom structures and instructional approaches. Furthermore, this study revealed gender inequity in Japanese students' conceptual understanding and self-efficacy. Limitations of the study, as well as

  13. Building shared understandings in introductory physics tutorials through risk, repair, conflict & comedy

    Science.gov (United States)

    Conlin, Luke D.

    Collaborative inquiry learning environments, such as The Tutorials in Physics Sensemaking, are designed to provide students with opportunities to partake in the authentic disciplinary practices of argumentation and sensemaking. Through these practices, groups of students in tutorial can build shared conceptual understandings of the mechanisms behind physical phenomena. In order to do so, they must also build a shared epistemological understanding of what they are doing together, such that their activity includes collaboratively making sense of mechanisms. Previous work (Conlin, Gupta, Scherr, & Hammer, 2007; Scherr & Hammer, 2009) has demonstrated that tutorial students do not settle upon only one way of understanding their activity together, but instead build multiple shared ways of understanding, or framing (Scherr & Hammer, 2009; Tannen, 1993a), their activity. I build upon this work by substantiating a preliminary finding that one of these shared ways of framing corresponds with increased evidence of the students' collaboratively making sense of physical mechanisms. What previous research has not yet addressed is how the students come to understand their activity as including collaborative sensemaking discussions in the first place, and how that understanding develops over the course of the semester. In this dissertation, I address both of these questions through an in-depth video analysis of three groups' discussions throughout the semester. To build shared understandings through scientific argumentation and collaborative sensemaking, the students need to continually make repairs of each other's understanding, but this comes with the risk of affective damage that can shut down further sensemaking discussions. By analyzing the discourse of the three groups' discussions throughout the semester, I show how each group is able to manage this essential tension as they each build and maintain a safe space to sensemake together. I find that the three groups differ in

  14. Identifying students’ mental models of sound propagation: The role of conceptual blending in understanding conceptual change

    Directory of Open Access Journals (Sweden)

    Zdeslav Hrepic

    2010-09-01

    Full Text Available We investigated introductory physics students’ mental models of sound propagation. We used a phenomenographic method to analyze the data in the study. In addition to the scientifically accepted Wave model, students used the “Entity” model to describe the propagation of sound. In this latter model sound is a self-standing entity, different from the medium through which it propagates. All other observed alternative models contain elements of both Entity and Wave models, but at the same time are distinct from each of the constituent models. We called these models “hybrid” or “blend” models. We discuss how students use these models in various contexts before and after instruction and how our findings contribute to the understanding of conceptual change. Implications of our findings for teaching are summarized.

  15. Assessing physical models used in nuclear aerosol transport models

    International Nuclear Information System (INIS)

    McDonald, B.H.

    1987-01-01

    Computer codes used to predict the behaviour of aerosols in water-cooled reactor containment buildings after severe accidents contain a variety of physical models. Special models are in place for describing agglomeration processes where small aerosol particles combine to form larger ones. Other models are used to calculate the rates at which aerosol particles are deposited on building structures. Condensation of steam on aerosol particles is currently a very active area in aerosol modelling. In this paper, the physical models incorporated in the current available international codes for all of these processes are reviewed and documented. There is considerable variation in models used in different codes, and some uncertainties exist as to which models are superior. 28 refs

  16. Understanding plasma catalysis through modelling and simulation—a review

    International Nuclear Information System (INIS)

    Neyts, E C; Bogaerts, A

    2014-01-01

    Plasma catalysis holds great promise for environmental applications, provided that the process viability can be maximized in terms of energy efficiency and product selectivity. This requires a fundamental understanding of the various processes taking place and especially the mutual interactions between plasma and catalyst. In this review, we therefore first examine the various effects of the plasma on the catalyst and of the catalyst on the plasma that have been described in the literature. Most of these studies are purely experimental. The urgently needed fundamental understanding of the mechanisms underpinning plasma catalysis, however, may also be obtained through modelling and simulation. Therefore, we also provide here an overview of the modelling efforts that have been developed already, on both the atomistic and the macroscale, and we identify the data that can be obtained with these models to illustrate how modelling and simulation may contribute to this field. Last but not least, we also identify future modelling opportunities to obtain a more complete understanding of the various underlying plasma catalytic effects, which is needed to provide a comprehensive picture of plasma catalysis. (paper)

  17. A high throughput platform for understanding the influence of excipients on physical and chemical stability

    DEFF Research Database (Denmark)

    Raijada, Dhara; Cornett, Claus; Rantanen, Jukka

    2013-01-01

    The present study puts forward a miniaturized high-throughput platform to understand influence of excipient selection and processing on the stability of a given drug compound. Four model drugs (sodium naproxen, theophylline, amlodipine besylate and nitrofurantoin) and ten different excipients were...... for chemical degradation. The proposed high-throughput platform can be used during early drug development to simulate typical processing induced stress in a small scale and to understand possible phase transformation behaviour and influence of excipients on this....

  18. Electromagnetic Physics Models for Parallel Computing Architectures

    International Nuclear Information System (INIS)

    Amadio, G; Bianchini, C; Iope, R; Ananya, A; Apostolakis, J; Aurora, A; Bandieramonte, M; Brun, R; Carminati, F; Gheata, A; Gheata, M; Goulas, I; Nikitina, T; Bhattacharyya, A; Mohanty, A; Canal, P; Elvira, D; Jun, S Y; Lima, G; Duhem, L

    2016-01-01

    The recent emergence of hardware architectures characterized by many-core or accelerated processors has opened new opportunities for concurrent programming models taking advantage of both SIMD and SIMT architectures. GeantV, a next generation detector simulation, has been designed to exploit both the vector capability of mainstream CPUs and multi-threading capabilities of coprocessors including NVidia GPUs and Intel Xeon Phi. The characteristics of these architectures are very different in terms of the vectorization depth and type of parallelization needed to achieve optimal performance. In this paper we describe implementation of electromagnetic physics models developed for parallel computing architectures as a part of the GeantV project. Results of preliminary performance evaluation and physics validation are presented as well. (paper)

  19. Electromagnetic Physics Models for Parallel Computing Architectures

    Science.gov (United States)

    Amadio, G.; Ananya, A.; Apostolakis, J.; Aurora, A.; Bandieramonte, M.; Bhattacharyya, A.; Bianchini, C.; Brun, R.; Canal, P.; Carminati, F.; Duhem, L.; Elvira, D.; Gheata, A.; Gheata, M.; Goulas, I.; Iope, R.; Jun, S. Y.; Lima, G.; Mohanty, A.; Nikitina, T.; Novak, M.; Pokorski, W.; Ribon, A.; Seghal, R.; Shadura, O.; Vallecorsa, S.; Wenzel, S.; Zhang, Y.

    2016-10-01

    The recent emergence of hardware architectures characterized by many-core or accelerated processors has opened new opportunities for concurrent programming models taking advantage of both SIMD and SIMT architectures. GeantV, a next generation detector simulation, has been designed to exploit both the vector capability of mainstream CPUs and multi-threading capabilities of coprocessors including NVidia GPUs and Intel Xeon Phi. The characteristics of these architectures are very different in terms of the vectorization depth and type of parallelization needed to achieve optimal performance. In this paper we describe implementation of electromagnetic physics models developed for parallel computing architectures as a part of the GeantV project. Results of preliminary performance evaluation and physics validation are presented as well.

  20. B physics beyond the Standard Model

    International Nuclear Information System (INIS)

    Hewett, J.A.L.

    1997-12-01

    The ability of present and future experiments to test the Standard Model in the B meson sector is described. The authors examine the loop effects of new interactions in flavor changing neutral current B decays and in Z → b anti b, concentrating on supersymmetry and the left-right symmetric model as specific examples of new physics scenarios. The procedure for performing a global fit to the Wilson coefficients which describe b → s transitions is outlined, and the results of such a fit from Monte Carlo generated data is compared to the predictions of the two sample new physics scenarios. A fit to the Zb anti b couplings from present data is also given

  1. A minimal physical model for crawling cells

    Science.gov (United States)

    Tiribocchi, Adriano; Tjhung, Elsen; Marenduzzo, Davide; Cates, Michael E.

    Cell motility in higher organisms (eukaryotes) is fundamental to biological functions such as wound healing or immune response, and is also implicated in diseases such as cancer. For cells crawling on solid surfaces, considerable insights into motility have been gained from experiments replicating such motion in vitro. Such experiments show that crawling uses a combination of actin treadmilling (polymerization), which pushes the front of a cell forward, and myosin-induced stress (contractility), which retracts the rear. We present a simplified physical model of a crawling cell, consisting of a droplet of active polar fluid with contractility throughout, but treadmilling connected to a thin layer near the supporting wall. The model shows a variety of shapes and/or motility regimes, some closely resembling cases seen experimentally. Our work supports the view that cellular motility exploits autonomous physical mechanisms whose operation does not need continuous regulatory effort.

  2. Understanding physical activity participation in spinal cord injured populations: Three narrative types for consideration

    Science.gov (United States)

    Papathomas, Anthony; Williams, Toni L.; Smith, Brett

    2015-01-01

    The aim of this study was to identity the types of physical activity narratives drawn upon by active spinal injured people. More than 50 h of semi-structured life-story interview data, collected as part of larger interdisciplinary program of disability lifestyle research, was analysed for 30 physically active male and female spinal cord injury (SCI) participants. A structural narrative analysis of data identified three narrative types which people with SCI draw on: (1) exercise is restitution, (2) exercise is medicine, and (3) exercise is progressive redemption. These insights contribute new knowledge by adding a unique narrative perspective to existing cognitive understanding of physical activity behaviour in the spinal cord injured population. The implications of this narrative typology for developing effective positive behavioural change interventions are critically discussed. It is concluded that the identified narratives types may be constitutive, as well as reflective, of physical activity experiences and therefore may be a useful tool on which to base physical activity promotion initiatives. PMID:26282868

  3. Understanding physical activity participation in spinal cord injured populations: Three narrative types for consideration

    Directory of Open Access Journals (Sweden)

    Anthony Papathomas

    2015-08-01

    Full Text Available The aim of this study was to identity the types of physical activity narratives drawn upon by active spinal injured people. More than 50 h of semi-structured life-story interview data, collected as part of larger interdisciplinary program of disability lifestyle research, was analysed for 30 physically active male and female spinal cord injury (SCI participants. A structural narrative analysis of data identified three narrative types which people with SCI draw on: (1 exercise is restitution, (2 exercise is medicine, and (3 exercise is progressive redemption. These insights contribute new knowledge by adding a unique narrative perspective to existing cognitive understanding of physical activity behaviour in the spinal cord injured population. The implications of this narrative typology for developing effective positive behavioural change interventions are critically discussed. It is concluded that the identified narratives types may be constitutive, as well as reflective, of physical activity experiences and therefore may be a useful tool on which to base physical activity promotion initiatives.

  4. Looking for physics beyond the standard model

    International Nuclear Information System (INIS)

    Binetruy, P.

    2002-01-01

    Motivations for new physics beyond the Standard Model are presented. The most successful and best motivated option, supersymmetry, is described in some detail, and the associated searches performed at LEP are reviewed. These include searches for additional Higgs bosons and for supersymmetric partners of the standard particles. These searches constrain the mass of the lightest supersymmetric particle which could be responsible for the dark matter of the universe. (authors)

  5. Statistical physics of pairwise probability models

    Directory of Open Access Journals (Sweden)

    Yasser Roudi

    2009-11-01

    Full Text Available Statistical models for describing the probability distribution over the states of biological systems are commonly used for dimensional reduction. Among these models, pairwise models are very attractive in part because they can be fit using a reasonable amount of data: knowledge of the means and correlations between pairs of elements in the system is sufficient. Not surprisingly, then, using pairwise models for studying neural data has been the focus of many studies in recent years. In this paper, we describe how tools from statistical physics can be employed for studying and using pairwise models. We build on our previous work on the subject and study the relation between different methods for fitting these models and evaluating their quality. In particular, using data from simulated cortical networks we study how the quality of various approximate methods for inferring the parameters in a pairwise model depends on the time bin chosen for binning the data. We also study the effect of the size of the time bin on the model quality itself, again using simulated data. We show that using finer time bins increases the quality of the pairwise model. We offer new ways of deriving the expressions reported in our previous work for assessing the quality of pairwise models.

  6. Physical models on discrete space and time

    International Nuclear Information System (INIS)

    Lorente, M.

    1986-01-01

    The idea of space and time quantum operators with a discrete spectrum has been proposed frequently since the discovery that some physical quantities exhibit measured values that are multiples of fundamental units. This paper first reviews a number of these physical models. They are: the method of finite elements proposed by Bender et al; the quantum field theory model on discrete space-time proposed by Yamamoto; the finite dimensional quantum mechanics approach proposed by Santhanam et al; the idea of space-time as lattices of n-simplices proposed by Kaplunovsky et al; and the theory of elementary processes proposed by Weizsaecker and his colleagues. The paper then presents a model proposed by the authors and based on the (n+1)-dimensional space-time lattice where fundamental entities interact among themselves 1 to 2n in order to build up a n-dimensional cubic lattice as a ground field where the physical interactions take place. The space-time coordinates are nothing more than the labelling of the ground field and take only discrete values. 11 references

  7. Generomak: Fusion physics, engineering and costing model

    International Nuclear Information System (INIS)

    Delene, J.G.; Krakowski, R.A.; Sheffield, J.; Dory, R.A.

    1988-06-01

    A generic fusion physics, engineering and economics model (Generomak) was developed as a means of performing consistent analysis of the economic viability of alternative magnetic fusion reactors. The original Generomak model developed at Oak Ridge by Sheffield was expanded for the analyses of the Senior Committee on Environmental Safety and Economics of Magnetic Fusion Energy (ESECOM). This report describes the Generomak code as used by ESECOM. The input data used for each of the ten ESECOM fusion plants and the Generomak code output for each case is given. 14 refs., 3 figs., 17 tabs

  8. Science Learning Cycle Method to Enhance the Conceptual Understanding and the Learning Independence on Physics Learning

    Science.gov (United States)

    Sulisworo, Dwi; Sutadi, Novitasari

    2017-01-01

    There have been many studies related to the implementation of cooperative learning. However, there are still many problems in school related to the learning outcomes on science lesson, especially in physics. The aim of this study is to observe the application of science learning cycle (SLC) model on improving scientific literacy for secondary…

  9. Gyrofluid Modeling of Turbulent, Kinetic Physics

    Science.gov (United States)

    Despain, Kate Marie

    2011-12-01

    Gyrofluid models to describe plasma turbulence combine the advantages of fluid models, such as lower dimensionality and well-developed intuition, with those of gyrokinetics models, such as finite Larmor radius (FLR) effects. This allows gyrofluid models to be more tractable computationally while still capturing much of the physics related to the FLR of the particles. We present a gyrofluid model derived to capture the behavior of slow solar wind turbulence and describe the computer code developed to implement the model. In addition, we describe the modifications we made to a gyrofluid model and code that simulate plasma turbulence in tokamak geometries. Specifically, we describe a nonlinear phase mixing phenomenon, part of the E x B term, that was previously missing from the model. An inherently FLR effect, it plays an important role in predicting turbulent heat flux and diffusivity levels for the plasma. We demonstrate this importance by comparing results from the updated code to studies done previously by gyrofluid and gyrokinetic codes. We further explain what would be necessary to couple the updated gyrofluid code, gryffin, to a turbulent transport code, thus allowing gryffin to play a role in predicting profiles for fusion devices such as ITER and to explore novel fusion configurations. Such a coupling would require the use of Graphical Processing Units (GPUs) to make the modeling process fast enough to be viable. Consequently, we also describe our experience with GPU computing and demonstrate that we are poised to complete a gryffin port to this innovative architecture.

  10. Understanding the impact of technology on firms’ business models

    DEFF Research Database (Denmark)

    Cavalcante, Sergio Andre

    2013-01-01

    of a new business model for the partner companies in the consortium. Practical implications – This paper is important in that it will help companies understand technological impact from a business model perspective, thereby enabling them to manage innovation better by distinguishing between the creation......, extension, revision or termination of business models. Originality/value – The main contribution of this study is its use of the business model perspective to analyse the impact of an emergent technology on companies’ innovation activities. This perspective makes it easier to develop strategic initiatives......Purpose – The purpose of this paper is to identify the impact of a new global positioning technology on firms’ business models. Design/methodology/approach – The empirical setting was a consortium of Danish organizations, established to develop a positioning-based technology platform as a basis...

  11. Agent-Based Models in Social Physics

    Science.gov (United States)

    Quang, Le Anh; Jung, Nam; Cho, Eun Sung; Choi, Jae Han; Lee, Jae Woo

    2018-06-01

    We review the agent-based models (ABM) on social physics including econophysics. The ABM consists of agent, system space, and external environment. The agent is autonomous and decides his/her behavior by interacting with the neighbors or the external environment with the rules of behavior. Agents are irrational because they have only limited information when they make decisions. They adapt using learning from past memories. Agents have various attributes and are heterogeneous. ABM is a non-equilibrium complex system that exhibits various emergence phenomena. The social complexity ABM describes human behavioral characteristics. In ABMs of econophysics, we introduce the Sugarscape model and the artificial market models. We review minority games and majority games in ABMs of game theory. Social flow ABM introduces crowding, evacuation, traffic congestion, and pedestrian dynamics. We also review ABM for opinion dynamics and voter model. We discuss features and advantages and disadvantages of Netlogo, Repast, Swarm, and Mason, which are representative platforms for implementing ABM.

  12. Nuclear physics aspects in the parton model of Feynman

    International Nuclear Information System (INIS)

    Pauchy Hwang, W.Y.

    1995-01-01

    The basic fact that pions couple strongly to nucleons has dominated various nuclear physics thinkings since the birth of the field more than sixty years ago. The parton model of Feynman, in which the structure of a nucleon (or a hadron) is characterized by a set of parton distributions, was proposed originally in late 1960's to treat high energy deep inelastic scattering, and later many other high energy physics experiments involving hadrons. Introduction of the concept of parton distributions signifies the departure of particle physics from nuclear physics. Following the suggestion that the sea quark distributions in a nucleon, at low and moderate Q 2 (at least up to a few GeV 2 ), can be attributed primarily to the probability of finding such quarks or antiquarks in the mesons (or recoiling baryons) associated with the nucleon, the author examines how nuclear physics aspects offer quantitative understanding of several recent experimental results, including the observed violation of the Gotfried sum rule and the so-called open-quotes proton spin crisisclose quotes. These results suggest that determination of parton distributions of a hadron at Q 2 of a few GeV 2 (and at small x) must in general take into account nuclear physics aspects. Implication of these results for other high-energy reactions, such as semi-inclusive hadron production in deep inelastic scattering, are also discussed

  13. Mutual understanding: a communication model for general practice.

    Science.gov (United States)

    Hantho, Arne; Jensen, Lena; Malterud, Kirsti

    2002-12-01

    To present our pursuits towards development of a simple model for clinical communication intended for application by the practitioner as a tool for enhancing mutual understanding. Inspired by theories about patient-centredness and interactive modes of understanding, and supported by the perspectives of the Danish philosopher Niels Thomassen, we reviewed audiotapes from our own consultations. Recognising four dimensions assumed to be essential for mutual understanding in the transcripts, we explored these dimensions further. We present a communication model consisting of the following dimensions: The Framework, within which the communication takes place; The Subject, about which the communication takes place; The Persons, between whom the communication takes place; and The Action, verbally and non-verbally, through which communication takes place. We describe these dimensions in detail. The nature of the dimensions indicates that there is an interrelationship between them, implying that the character of the communication may change if one of the factors is changed. Analysis of an ongoing or recent consultation completed in accordance with these four dimensions allows the doctor to refocus the communication, thus leading to a more extensive mutual understanding and perhaps enhanced freedom of action.

  14. Understanding complex urban systems multidisciplinary approaches to modeling

    CERN Document Server

    Gurr, Jens; Schmidt, J

    2014-01-01

    Understanding Complex Urban Systems takes as its point of departure the insight that the challenges of global urbanization and the complexity of urban systems cannot be understood – let alone ‘managed’ – by sectoral and disciplinary approaches alone. But while there has recently been significant progress in broadening and refining the methodologies for the quantitative modeling of complex urban systems, in deepening the theoretical understanding of cities as complex systems, or in illuminating the implications for urban planning, there is still a lack of well-founded conceptual thinking on the methodological foundations and the strategies of modeling urban complexity across the disciplines. Bringing together experts from the fields of urban and spatial planning, ecology, urban geography, real estate analysis, organizational cybernetics, stochastic optimization, and literary studies, as well as specialists in various systems approaches and in transdisciplinary methodologies of urban analysis, the volum...

  15. Understanding rare disease pathogenesis: a grand challenge for model organisms.

    Science.gov (United States)

    Hieter, Philip; Boycott, Kym M

    2014-10-01

    In this commentary, Philip Hieter and Kym Boycott discuss the importance of model organisms for understanding pathogenesis of rare human genetic diseases, and highlight the work of Brooks et al., "Dysfunction of 60S ribosomal protein L10 (RPL10) disrupts neurodevelopment and causes X-linked microcephaly in humans," published in this issue of GENETICS. Copyright © 2014 by the Genetics Society of America.

  16. Undergraduate students’ challenges with computational modelling in physics

    Directory of Open Access Journals (Sweden)

    Simen A. Sørby

    2012-12-01

    Full Text Available In later years, computational perspectives have become essential parts in several of the University of Oslo’s natural science studies. In this paper we discuss some main findings from a qualitative study of the computational perspectives’ impact on the students’ work with their first course in physics– mechanics – and their learning and meaning making of its contents. Discussions of the students’ learning of physics are based on sociocultural theory, which originates in Vygotsky and Bakhtin, and subsequent physics education research. Results imply that the greatest challenge for students when working with computational assignments is to combine knowledge from previously known, but separate contexts. Integrating knowledge of informatics, numerical and analytical mathematics and conceptual understanding of physics appears as a clear challenge for the students. We also observe alack of awareness concerning the limitations of physical modelling. The students need help with identifying the appropriate knowledge system or “tool set”, for the different tasks at hand; they need helpto create a plan for their modelling and to become aware of its limits. In light of this, we propose thatan instructive and dialogic text as basis for the exercises, in which the emphasis is on specification, clarification and elaboration, would be of potential great aid for students who are new to computational modelling.

  17. Models to support students’ understanding of measuring area of circles

    Science.gov (United States)

    Rejeki, S.; Putri, R. I. I.

    2018-01-01

    Many studies showed that enormous students got confused about the concepts of measuring area of circles. The main reason is because mathematics classroom practices emphasized on memorizing formulas rather than understanding concepts. Therefore, in this study, a set of learning activities were designed as an innovation in learning area measurement of circles. The activities involved two models namely grid paper and reshaping which are respectively as a means and a strategy to support students’ learning of area measurement of circles. Design research was used as the research approach to achieve the aim. Thirty-eight of 8th graders in Indonesia were involved in this study. In this study, together with the contextual problems, the grid paper and reshaping sectors, which used as the models in this learning, helped the students to gradually develop their understanding of the area measurement of circles. The grid papers plays important role in comparing and estimating areas. Whereas, the reshaping sectors might support students’ understanding of the circumference and the area measurement of circles. Those two models could be the tool for promoting the informal theory of area measurement. Besides, the whole activities gave important role on distinguishing the area and perimeter of circles.

  18. Understanding political radicalization: The two-pyramids model.

    Science.gov (United States)

    McCauley, Clark; Moskalenko, Sophia

    2017-04-01

    This article reviews some of the milestones of thinking about political radicalization, as scholars and security officials struggled after 9/11 to discern the precursors of terrorist violence. Recent criticism of the concept of radicalization has been recognized, leading to a 2-pyramids model that responds to the criticism by separating radicalization of opinion from radicalization of action. Security and research implications of the 2-pyramids model are briefly described, ending with a call for more attention to emotional experience in understanding both radicalization of opinion and radicalization of action. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  19. [Understanding King's model on the paradigm of symbolic interactionism].

    Science.gov (United States)

    Araújo, Iliana Maria de Almeida; Oliveira, Marcos Venícios; de Oliveira, Marcos Venícius; Fernandes, Ana Fátima Carvalho

    2005-01-01

    It was aimed to reflect on King's Theory, according to the approach of Symbolic Interaccionism, and theory analyses model of Meleis. To reach the objective, we proceeded the reading of the three models as mentioned before, looking for the consistencies and discrepancies among the concepts and correlating them. The study allowed to conclude that the theories agree when elucidating the man as a being that reacts and search to understand the meaning of things to his/her circuit, drifting and judging their actions and the one of the other ones. It is important the subject of the meanings could be modified and they generate the elaboration of goals in common.

  20. Modellus: Learning Physics with Mathematical Modelling

    Science.gov (United States)

    Teodoro, Vitor

    Computers are now a major tool in research and development in almost all scientific and technological fields. Despite recent developments, this is far from true for learning environments in schools and most undergraduate studies. This thesis proposes a framework for designing curricula where computers, and computer modelling in particular, are a major tool for learning. The framework, based on research on learning science and mathematics and on computer user interface, assumes that: 1) learning is an active process of creating meaning from representations; 2) learning takes place in a community of practice where students learn both from their own effort and from external guidance; 3) learning is a process of becoming familiar with concepts, with links between concepts, and with representations; 4) direct manipulation user interfaces allow students to explore concrete-abstract objects such as those of physics and can be used by students with minimal computer knowledge. Physics is the science of constructing models and explanations about the physical world. And mathematical models are an important type of models that are difficult for many students. These difficulties can be rooted in the fact that most students do not have an environment where they can explore functions, differential equations and iterations as primary objects that model physical phenomena--as objects-to-think-with, reifying the formal objects of physics. The framework proposes that students should be introduced to modelling in a very early stage of learning physics and mathematics, two scientific areas that must be taught in very closely related way, as they were developed since Galileo and Newton until the beginning of our century, before the rise of overspecialisation in science. At an early stage, functions are the main type of objects used to model real phenomena, such as motions. At a later stage, rates of change and equations with rates of change play an important role. This type of equations

  1. The Effect of Computer Models as Formative Assessment on Student Understanding of the Nature of Models

    Science.gov (United States)

    Park, Mihwa; Liu, Xiufeng; Smith, Erica; Waight, Noemi

    2017-01-01

    This study reports the effect of computer models as formative assessment on high school students' understanding of the nature of models. Nine high school teachers integrated computer models and associated formative assessments into their yearlong high school chemistry course. A pre-test and post-test of students' understanding of the nature of…

  2. Understanding immunology: fun at an intersection of the physical, life, and clinical sciences

    Science.gov (United States)

    Chakraborty, Arup K.

    2014-10-01

    Understanding how the immune system works is a grand challenge in science with myriad direct implications for improving human health. The immune system protects us from infectious pathogens and cancer, and maintains a harmonious steady state with essential microbiota in our gut. Vaccination, the medical procedure that has saved more lives than any other, involves manipulating the immune system. Unfortunately, the immune system can also go awry to cause autoimmune diseases. Immune responses are the product of stochastic collective dynamic processes involving many interacting components. These processes span multiple scales of length and time. Thus, statistical mechanics has much to contribute to immunology, and the oeuvre of biological physics will be further enriched if the number of physical scientists interested in immunology continues to increase. I describe how I got interested in immunology and provide a glimpse of my experiences working on immunology using approaches from statistical mechanics and collaborating closely with immunologists.

  3. The Impact of Problem-Based Learning on Engineering Students' Beliefs about Physics and Conceptual Understanding of Energy and Momentum

    Science.gov (United States)

    Sahin, Mehmet

    2010-01-01

    The purpose of this paper is to investigate the impact of problem-based learning (PBL) on freshmen engineering students' beliefs about physics and physics learning (referred to as epistemological beliefs) and conceptual understanding of physics. The multiple-choice test of energy and momentum concepts and the Colorado learning attitudes about…

  4. Understanding low levels of physical activity in people with intellectual disabilities : A systematic review to identify barriers and facilitators

    NARCIS (Netherlands)

    Bossink, Leontien; van der Putten, Annette; Vlaskamp, Carla

    2017-01-01

    Background: People with intellectual disabilities (ID) undertake extremely low levels of physical activity. Aims: To enhance understanding concerning low levels of physical activity in people with ID, this study has three aims: (1) to identify barriers to and facilitators of physical activity in

  5. Why Social Relationships Are Important for Physical Health: A Systems Approach to Understanding and Modifying Risk and Protection.

    Science.gov (United States)

    Holt-Lunstad, Julianne

    2018-01-04

    Social relationships are adaptive and crucial for survival. This review presents existing evidence indicating that our social connections to others have powerful influences on health and longevity and that lacking social connection qualifies as a risk factor for premature mortality. A systems perspective is presented as a framework by which to move social connection into the realm of public health. Individuals, and health-relevant biological processes, exist within larger social contexts including the family, neighborhood and community, and society and culture. Applying the social ecological model, this review highlights the interrelationships of individuals within groups in terms of understanding both the causal mechanisms by which social connection influences physical health and the ways in which this influence can inform potential intervention strategies. A systems approach also helps identify gaps in our current understanding that may guide future research.

  6. Theory Building- Towards an understanding of business model innovation processes

    DEFF Research Database (Denmark)

    Taran, Yariv; Boer, Harry; Lindgren, Peter

    2009-01-01

    Companies today, in some industries more than others, invest more capital and resources just to stay competitive, develop more diverse solutions, and increasingly start to think more radically, when considering to innovate their business model. However, the development and innovation of business...... models is a complex venture and has not been widely researched yet. The objective of this paper is therefore 1) to build a [descriptive] theoretical understanding, based on Christensen's (2005) three-step procedure, to business models and their innovation and, as a result of that, 2) to strengthen...... researchers' and practitioners' perspectives as to how the process of business model innovation can be realized. By using various researchers' perspectives and assumptions, we identify relevant inconsistencies, which consequently lead us to propose possible supplementary solutions. We conclude our paper...

  7. Physics Beyond the Standard Model: Supersymmetry

    Energy Technology Data Exchange (ETDEWEB)

    Nojiri, M.M.; /KEK, Tsukuba /Tsukuba, Graduate U. Adv. Studies /Tokyo U.; Plehn, T.; /Edinburgh U.; Polesello, G.; /INFN, Pavia; Alexander, John M.; /Edinburgh U.; Allanach, B.C.; /Cambridge U.; Barr, Alan J.; /Oxford U.; Benakli, K.; /Paris U., VI-VII; Boudjema, F.; /Annecy, LAPTH; Freitas, A.; /Zurich U.; Gwenlan, C.; /University Coll. London; Jager, S.; /CERN /LPSC, Grenoble

    2008-02-01

    This collection of studies on new physics at the LHC constitutes the report of the supersymmetry working group at the Workshop 'Physics at TeV Colliders', Les Houches, France, 2007. They cover the wide spectrum of phenomenology in the LHC era, from alternative models and signatures to the extraction of relevant observables, the study of the MSSM parameter space and finally to the interplay of LHC observations with additional data expected on a similar time scale. The special feature of this collection is that while not each of the studies is explicitly performed together by theoretical and experimental LHC physicists, all of them were inspired by and discussed in this particular environment.

  8. 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

  9. Understanding rapid theoretical change in particle physics: a month-by-month co-citation analysis

    International Nuclear Information System (INIS)

    Sullivan, D.; Koester, D.; White, D.H.; Kern, R.

    1979-01-01

    While co-citation analysis has proved a powerful tool in the study of changes in intellectual foci in science, no one has ever used the technique to study very rapid changes in the theoretical structure of a scientific field. This paper presents month-by-month co-citation analyses of key phases in the weak-electromagnetic unification research program within particle physics, and shows that these analyses capture and illuminate very rapid intellectual changes. These data provide yet another illustration of the utility of co-citation analysis for understanding the history of science. 8 figures

  10. Models in Physics, Models for Physics Learning, and Why the Distinction May Matter in the Case of Electric Circuits

    Science.gov (United States)

    Hart, Christina

    2008-01-01

    Models are important both in the development of physics itself and in teaching physics. Historically, the consensus models of physics have come to embody particular ontological assumptions and epistemological commitments. Educators have generally assumed that the consensus models of physics, which have stood the test of time, will also work well…

  11. Children's conceptions of physical events: explicit and tacit understanding of horizontal motion.

    Science.gov (United States)

    Howe, Christine; Taylor Tavares, Joana; Devine, Amy

    2014-06-01

    The conceptual understanding that children display when predicting physical events has been shown to be inferior to the understanding they display when recognizing whether events proceed naturally. This has often been attributed to differences between the explicit engagement with conceptual knowledge required for prediction and the tacit engagement that suffices for recognition, and contrasting theories have been formulated to characterize the differences. Focusing on a theory that emphasizes omission at the explicit level of conceptual elements that are tacitly understood, the paper reports two studies that attempt clarification. The studies are concerned with 6- to 10-year-old children's understanding of, respectively, the direction (141 children) and speed (132 children) of motion in a horizontal direction. Using computer-presented billiards scenarios, the children predicted how balls would move (prediction task) and judged whether or not simulated motion was correct (recognition task). Results indicate that the conceptions underpinning prediction are sometimes interpretable as partial versions of the conceptions underpinning recognition, as the omission hypothesis would imply. However, there are also qualitative differences, which suggest partial dissociation between explicit and tacit understanding. It is suggested that a theoretical perspective that acknowledges this dissociation would provide the optimal framework for future research. © 2013 The British Psychological Society.

  12. Algebraic fermion models and nuclear structure physics

    International Nuclear Information System (INIS)

    Troltenier, Dirk; Blokhin, Andrey; Draayer, Jerry P.; Rompf, Dirk; Hirsch, Jorge G.

    1996-01-01

    Recent experimental and theoretical developments are generating renewed interest in the nuclear SU(3) shell model, and this extends to the symplectic model, with its Sp(6,R) symmetry, which is a natural multi-(ℎ/2π)ω extension of the SU(3) theory. First and foremost, an understanding of how the dynamics of a quantum rotor is embedded in the shell model has established it as the model of choice for describing strongly deformed systems. Second, the symplectic model extension of the 0-(ℎ/2π)ω theory can be used to probe additional degrees of freedom, like core polarization and vorticity modes that play a key role in providing a full description of quadrupole collectivity. Third, the discovery and understanding of pseudo-spin has allowed for an extension of the theory from light (A≤40) to heavy (A≥100) nuclei. Fourth, a user-friendly computer code for calculating reduced matrix elements of operators that couple SU(3) representations is now available. And finally, since the theory is designed to cope with deformation in a natural way, microscopic features of deformed systems can be probed; for example, the theory is now being employed to study double beta decay and thereby serves to probe the validity of the standard model of particles and their interactions. A subset of these topics will be considered in this course--examples cited include: a consideration of the origin of pseudo-spin symmetry; a SU(3)-based interpretation of the coupled-rotor model, early results of double beta decay studies; and some recent developments on the pseudo-SU(3) theory. Nothing will be said about other fermion-based theories; students are referred to reviews in the literature for reports on developments in these related areas

  13. Physical model for membrane protrusions during spreading

    International Nuclear Information System (INIS)

    Chamaraux, F; Ali, O; Fourcade, B; Keller, S; Bruckert, F

    2008-01-01

    During cell spreading onto a substrate, the kinetics of the contact area is an observable quantity. This paper is concerned with a physical approach to modeling this process in the case of ameboid motility where the membrane detaches itself from the underlying cytoskeleton at the leading edge. The physical model we propose is based on previous reports which highlight that membrane tension regulates cell spreading. Using a phenomenological feedback loop to mimic stress-dependent biochemistry, we show that the actin polymerization rate can be coupled to the stress which builds up at the margin of the contact area between the cell and the substrate. In the limit of small variation of membrane tension, we show that the actin polymerization rate can be written in a closed form. Our analysis defines characteristic lengths which depend on elastic properties of the membrane–cytoskeleton complex, such as the membrane–cytoskeleton interaction, and on molecular parameters, the rate of actin polymerization. We discuss our model in the case of axi-symmetric and non-axi-symmetric spreading and we compute the characteristic time scales as a function of fundamental elastic constants such as the strength of membrane–cytoskeleton adherence

  14. Understanding the Pathogenesis of Angelman Syndrome through Animal Models

    Directory of Open Access Journals (Sweden)

    Nihar Ranjan Jana

    2012-01-01

    Full Text Available Angelman syndrome (AS is a neurodevelopmental disorder characterized by severe mental retardation, lack of speech, ataxia, susceptibility to seizures, and unique behavioral features such as easily provoked smiling and laughter and autistic features. The disease is primarily caused by deletion or loss-of-function mutations of the maternally inherited UBE3A gene located within chromosome 15q11-q13. The UBE3A gene encodes a 100 kDa protein that functions as ubiquitin ligase and transcriptional coactivator. Emerging evidence now indicates that UBE3A plays a very important role in synaptic function and in regulation of activity-dependent synaptic plasticity. A number of animal models for AS have been generated to understand the disease pathogenesis. The most widely used model is the UBE3A-maternal-deficient mouse that recapitulates most of the essential features of AS including cognitive and motor abnormalities. This paper mainly discusses various animal models of AS and how these models provide fundamental insight into understanding the disease biology for potential therapeutic intervention.

  15. Physical and mathematical modeling of antimicrobial photodynamic therapy

    Science.gov (United States)

    Bürgermeister, Lisa; López, Fernando Romero; Schulz, Wolfgang

    2014-07-01

    Antimicrobial photodynamic therapy (aPDT) is a promising method to treat local bacterial infections. The therapy is painless and does not cause bacterial resistances. However, there are gaps in understanding the dynamics of the processes, especially in periodontal treatment. This work describes the advances in fundamental physical and mathematical modeling of aPDT used for interpretation of experimental evidence. The result is a two-dimensional model of aPDT in a dental pocket phantom model. In this model, the propagation of laser light and the kinetics of the chemical reactions are described as coupled processes. The laser light induces the chemical processes depending on its intensity. As a consequence of the chemical processes, the local optical properties and distribution of laser light change as well as the reaction rates. The mathematical description of these coupled processes will help to develop treatment protocols and is the first step toward an inline feedback system for aPDT users.

  16. Beyond the standard model with B and K physics

    International Nuclear Information System (INIS)

    Grossman, Y

    2003-01-01

    In the first part of the talk the flavor physics input to models beyond the standard model is described. One specific example of such new physics model is given: A model with bulk fermions in a non factorizable one extra dimension. In the second part of the talk we discuss several observables that are sensitive to new physics. We explain what type of new physics can produce deviations from the standard model predictions in each of these observables

  17. Understanding Emergency Care Delivery Through Computer Simulation Modeling.

    Science.gov (United States)

    Laker, Lauren F; Torabi, Elham; France, Daniel J; Froehle, Craig M; Goldlust, Eric J; Hoot, Nathan R; Kasaie, Parastu; Lyons, Michael S; Barg-Walkow, Laura H; Ward, Michael J; Wears, Robert L

    2018-02-01

    In 2017, Academic Emergency Medicine convened a consensus conference entitled, "Catalyzing System Change through Health Care Simulation: Systems, Competency, and Outcomes." This article, a product of the breakout session on "understanding complex interactions through systems modeling," explores the role that computer simulation modeling can and should play in research and development of emergency care delivery systems. This article discusses areas central to the use of computer simulation modeling in emergency care research. The four central approaches to computer simulation modeling are described (Monte Carlo simulation, system dynamics modeling, discrete-event simulation, and agent-based simulation), along with problems amenable to their use and relevant examples to emergency care. Also discussed is an introduction to available software modeling platforms and how to explore their use for research, along with a research agenda for computer simulation modeling. Through this article, our goal is to enhance adoption of computer simulation, a set of methods that hold great promise in addressing emergency care organization and design challenges. © 2017 by the Society for Academic Emergency Medicine.

  18. Self-organizing Map Analysis for Understanding Comprehensive Relationships between Formulation Variables, State of Water, and the Physical Stability of Pharmaceutical Emulsions

    OpenAIRE

    Onuki, Yoshinori; Hasegawa, Naoki; Horita, Akihiro; Ueno, Naomi; Kida, Chihiro; Hayashi, Yoshihiro; Obata, Yasuko; Toshokan, Toshokan

    2015-01-01

    The physical stability of pharmaceutical emulsions is an important quality attribute to be considered. To obtain a better understanding of this issue, this study investigated the contribution of the state of water to the physical stability of pharmaceutical emulsions. The key technology to evaluate the state of water was magnetic resonance imaging (MRI). For sample preparation, model emulsions with different formulation variables (surfactant content, water content, and hydrophilic–lipophilic ...

  19. Towards developing understanding of the drivers, constraints from the consumption values underpinning participation in physical activity.

    OpenAIRE

    Kearns, PJ; Williams-Burnett, N; Skinner, H

    2012-01-01

    Overall participation rates in physical activity across the UK have remained relatively static since the mid 1980s, with attendant causes for concern about the inequality of participation rates amongst various target groups that may be worthy of specific investigation. Behaviour change models from the fields of leisure studies, consumer behaviour and social psychology offer conceptualisation of a notion of exchange underpinning the expectancy-value process, noting that, in order to facilitate...

  20. Pre-Service Physics Teachers' Argumentation in a Model Rocketry Physics Experience

    Science.gov (United States)

    Gürel, Cem; Süzük, Erol

    2017-01-01

    This study investigates the quality of argumentation developed by a group of pre-service physics teachers' (PSPT) as an indicator of subject matter knowledge on model rocketry physics. The structure of arguments and scientific credibility model was used as a design framework in the study. The inquiry of model rocketry physics was employed in…

  1. Physical and Chemical Environmental Abstraction Model

    International Nuclear Information System (INIS)

    Nowak, E.

    2000-01-01

    As directed by a written development plan (CRWMS M and O 1999a), Task 1, an overall conceptualization of the physical and chemical environment (P/CE) in the emplacement drift is documented in this Analysis/Model Report (AMR). Included are the physical components of the engineered barrier system (EBS). The intended use of this descriptive conceptualization is to assist the Performance Assessment Department (PAD) in modeling the physical and chemical environment within a repository drift. It is also intended to assist PAD in providing a more integrated and complete in-drift geochemical model abstraction and to answer the key technical issues raised in the U.S. Nuclear Regulatory Commission (NRC) Issue Resolution Status Report (IRSR) for the Evolution of the Near-Field Environment (NFE) Revision 2 (NRC 1999). EBS-related features, events, and processes (FEPs) have been assembled and discussed in ''EBS FEPs/Degradation Modes Abstraction'' (CRWMS M and O 2000a). Reference AMRs listed in Section 6 address FEPs that have not been screened out. This conceptualization does not directly address those FEPs. Additional tasks described in the written development plan are recommended for future work in Section 7.3. To achieve the stated purpose, the scope of this document includes: (1) the role of in-drift physical and chemical environments in the Total System Performance Assessment (TSPA) (Section 6.1); (2) the configuration of engineered components (features) and critical locations in drifts (Sections 6.2.1 and 6.3, portions taken from EBS Radionuclide Transport Abstraction (CRWMS M and O 2000b)); (3) overview and critical locations of processes that can affect P/CE (Section 6.3); (4) couplings and relationships among features and processes in the drifts (Section 6.4); and (5) identities and uses of parameters transmitted to TSPA by some of the reference AMRs (Section 6.5). This AMR originally considered a design with backfill, and is now being updated (REV 00 ICN1) to address

  2. Relativistic nuclear physics with the spectator model

    International Nuclear Information System (INIS)

    Gross, F.

    1988-01-01

    The spectator model, a general approach to the relativistic treatment of nuclear physics problems in which spectators to nuclear interactions are put on their mass-shell, will be defined nd described. The approach grows out of the relativistic treatment of two and three body systems in which one particle is off-shell, and recent numerical results for the NN interaction will be presented. Two meson-exchange models, one with only 4 mesons (π, σ, /rho/, ω) but with a 25% admixture of γ 5 coupling for the pion, and a second with 6 mesons (π, σ, /rho/, ω, δ, and /eta/) but a pure γ 5 γ/sup mu/ pion coupling, are shown to give very good quantitative fits to NN scattering phase shifts below 400 MeV, and also a good description of the /rho/ 40 Cα elastic scattering observables. 19 refs., 6 figs., 1 tab

  3. REPFLO model evaluation, physical and numerical consistency

    International Nuclear Information System (INIS)

    Wilson, R.N.; Holland, D.H.

    1978-11-01

    This report contains a description of some suggested changes and an evaluation of the REPFLO computer code, which models ground-water flow and nuclear-waste migration in and about a nuclear-waste repository. The discussion contained in the main body of the report is supplemented by a flow chart, presented in the Appendix of this report. The suggested changes are of four kinds: (1) technical changes to make the code compatible with a wider variety of digital computer systems; (2) changes to fill gaps in the computer code, due to missing proprietary subroutines; (3) changes to (a) correct programming errors, (b) correct logical flaws, and (c) remove unnecessary complexity; and (4) changes in the computer code logical structure to make REPFLO a more viable model from the physical point of view

  4. Understanding the physical dynamics and ecological interactions in tidal stream energy environments

    Science.gov (United States)

    Fraser, Shaun; Williamson, Benjamin J.; Nikora, Vladimir; Scott, Beth E.

    2017-04-01

    Tidal stream energy devices are intended to operate in energetic physical environments characterised by high flows and extreme turbulence. These environments are often of ecological importance to a range of marine species. Understanding the physical dynamics and ecological interactions at fine scales in such sites is essential for device/array design and to understand environmental impacts. However, investigating fine scale characteristics requires high resolution field measurements which are difficult to attain and interpret, with data often confounded by interference related to turbulence. Consequently, field observations in tidal stream energy environments are limited and require the development of specialised analysis methods and so significant knowledge gaps are still present. The seabed mounted FLOWBEC platform is addressing these knowledge gaps using upward facing instruments to collect information from around marine energy infrastructure. Multifrequency and multibeam echosounder data provide detailed information on the distribution and interactions of biological targets, such as fish and diving seabirds, while simultaneously recording the scales and intensity of turbulence. Novel processing methodologies and instrument integration techniques have been developed which combine different data types and successfully separates signal from noise to reveal new evidence about the behaviour of mobile species and the structure of turbulence at all speeds of the tide and throughout the water column. Multiple platform deployments in the presence and absence of marine energy infrastructure reveal the natural characteristics of high energy sites, and enable the interpretation of the physical and biological impacts of tidal stream devices. These methods and results are relevant to the design and consenting of marine renewable energy technologies, and provide novel information on the use of turbulence for foraging opportunities in high energy sites by mobile species.

  5. "That part of the body is just gone": understanding and responding to dissociation and physical health.

    Science.gov (United States)

    Haven, Terri J

    2009-01-01

    The past 2 decades have brought a significant surge in interest and research regarding the ways in which psychological trauma relates to the physical body. Researchers now understand a great deal about how the brain and the body process traumatic experiences, as well as the increased likelihood of an array of physical health consequences associated with both childhood and adult trauma and posttraumatic stress disorder. Experts are increasingly challenging mind-body dualism through solid theoretical and clinical bases for the central importance of listening to and communicating with trauma clients' bodies as part of reducing the suffering and long-lasting consequences of trauma. This article integrates this growing body of knowledge through a particular focus on trauma-induced dissociation and the implications of the physical and neurological processes and consequences of dissociation on clients' ability to participate in caring for their own bodies. The author utilizes an in-depth clinical example of expanding relational trauma psychotherapy to include a focus on working directly with trauma-related sensorimotor and physiological sensations and patterns.

  6. Propulsion Physics Using the Chameleon Density Model

    Science.gov (United States)

    Robertson, Glen A.

    2011-01-01

    To grow as a space faring race, future spaceflight systems will require a new theory of propulsion. Specifically one that does not require mass ejection without limiting the high thrust necessary to accelerate within or beyond our solar system and return within a normal work period or lifetime. The Chameleon Density Model (CDM) is one such model that could provide new paths in propulsion toward this end. The CDM is based on Chameleon Cosmology a dark matter theory; introduced by Khrouy and Weltman in 2004. Chameleon as it is hidden within known physics, where the Chameleon field represents a scalar field within and about an object; even in the vacuum. The CDM relates to density changes in the Chameleon field, where the density changes are related to matter accelerations within and about an object. These density changes in turn change how an object couples to its environment. Whereby, thrust is achieved by causing a differential in the environmental coupling about an object. As a demonstration to show that the CDM fits within known propulsion physics, this paper uses the model to estimate the thrust from a solid rocket motor. Under the CDM, a solid rocket constitutes a two body system, i.e., the changing density of the rocket and the changing density in the nozzle arising from the accelerated mass. Whereby, the interactions between these systems cause a differential coupling to the local gravity environment of the earth. It is shown that the resulting differential in coupling produces a calculated value for the thrust near equivalent to the conventional thrust model used in Sutton and Ross, Rocket Propulsion Elements. Even though imbedded in the equations are the Universe energy scale factor, the reduced Planck mass and the Planck length, which relates the large Universe scale to the subatomic scale.

  7. Understanding the tropical warm temperature bias simulated by climate models

    Science.gov (United States)

    Brient, Florent; Schneider, Tapio

    2017-04-01

    The state-of-the-art coupled general circulation models have difficulties in representing the observed spatial pattern of surface tempertaure. A majority of them suffers a warm bias in the tropical subsiding regions located over the eastern parts of oceans. These regions are usually covered by low-level clouds scattered from stratus along the coasts to more vertically developed shallow cumulus farther from them. Models usually fail to represent accurately this transition. Here we investigate physical drivers of this warm bias in CMIP5 models through a near-surface energy budget perspective. We show that overestimated solar insolation due to a lack of stratocumulus mostly explains the warm bias. This bias also arises partly from inter-model differences in surface fluxes that could be traced to differences in near-surface relative humidity and air-sea temperature gradient. We investigate the role of the atmosphere in driving surface biases by comparing historical and atmopsheric (AMIP) experiments. We show that some differences in boundary-layer characteristics, mostly those related to cloud fraction and relative humidity, are already present in AMIP experiments and may be the drivers of coupled biases. This gives insights in how models can be improved for better simulations of the tropical climate.

  8. Working group report: Flavor physics and model building

    Indian Academy of Sciences (India)

    cO Indian Academy of Sciences. Vol. ... This is the report of flavor physics and model building working group at ... those in model building have been primarily devoted to neutrino physics. ..... [12] Andrei Gritsan, ICHEP 2004, Beijing, China.

  9. Precision Higgs Boson Physics and Implications for Beyond the Standard Model Physics Theories

    International Nuclear Information System (INIS)

    Wells, James

    2015-01-01

    The discovery of the Higgs boson is one of science's most impressive recent achievements. We have taken a leap forward in understanding what is at the heart of elementary particle mass generation. We now have a significant opportunity to develop even deeper understanding of how the fundamental laws of nature are constructed. As such, we need intense focus from the scientific community to put this discovery in its proper context, to realign and narrow our understanding of viable theory based on this positive discovery, and to detail the implications the discovery has for theories that attempt to answer questions beyond what the Standard Model can explain. This project's first main object is to develop a state-of-the-art analysis of precision Higgs boson physics. This is to be done in the tradition of the electroweak precision measurements of the LEP/SLC era. Indeed, the electroweak precision studies of the past are necessary inputs to the full precision Higgs program. Calculations will be presented to the community of Higgs boson observables that detail just how well various couplings of the Higgs boson can be measured, and more. These will be carried out using state-of-the-art theory computations coupled with the new experimental results coming in from the LHC. The project's second main objective is to utilize the results obtained from LHC Higgs boson experiments and the precision analysis, along with the direct search studies at LHC, and discern viable theories of physics beyond the Standard Model that unify physics to a deeper level. Studies will be performed on supersymmetric theories, theories of extra spatial dimensions (and related theories, such as compositeness), and theories that contain hidden sector states uniquely accessible to the Higgs boson. In addition, if data becomes incompatible with the Standard Model's low-energy effective lagrangian, new physics theories will be developed that explain the anomaly and put it into a more

  10. Impact of Learning Model Based on Cognitive Conflict toward Student’s Conceptual Understanding

    Science.gov (United States)

    Mufit, F.; Festiyed, F.; Fauzan, A.; Lufri, L.

    2018-04-01

    The problems that often occur in the learning of physics is a matter of misconception and low understanding of the concept. Misconceptions do not only happen to students, but also happen to college students and teachers. The existing learning model has not had much impact on improving conceptual understanding and remedial efforts of student misconception. This study aims to see the impact of cognitive-based learning model in improving conceptual understanding and remediating student misconceptions. The research method used is Design / Develop Research. The product developed is a cognitive conflict-based learning model along with its components. This article reports on product design results, validity tests, and practicality test. The study resulted in the design of cognitive conflict-based learning model with 4 learning syntaxes, namely (1) preconception activation, (2) presentation of cognitive conflict, (3) discovery of concepts & equations, (4) Reflection. The results of validity tests by some experts on aspects of content, didactic, appearance or language, indicate very valid criteria. Product trial results also show a very practical product to use. Based on pretest and posttest results, cognitive conflict-based learning models have a good impact on improving conceptual understanding and remediating misconceptions, especially in high-ability students.

  11. Fuzzy modelling of Atlantic salmon physical habitat

    Science.gov (United States)

    St-Hilaire, André; Mocq, Julien; Cunjak, Richard

    2015-04-01

    Fish habitat models typically attempt to quantify the amount of available river habitat for a given fish species for various flow and hydraulic conditions. To achieve this, information on the preferred range of values of key physical habitat variables (e.g. water level, velocity, substrate diameter) for the targeted fishs pecies need to be modelled. In this context, we developed several habitat suitability indices sets for three Atlantic salmon life stages (young-of-the-year (YOY), parr, spawning adults) with the help of fuzzy logic modeling. Using the knowledge of twenty-seven experts, from both sides of the Atlantic Ocean, we defined fuzzy sets of four variables (depth, substrate size, velocity and Habitat Suitability Index, or HSI) and associated fuzzy rules. When applied to the Romaine River (Canada), median curves of standardized Weighted Usable Area (WUA) were calculated and a confidence interval was obtained by bootstrap resampling. Despite the large range of WUA covered by the expert WUA curves, confidence intervals were relatively narrow: an average width of 0.095 (on a scale of 0 to 1) for spawning habitat, 0.155 for parr rearing habitat and 0.160 for YOY rearing habitat. When considering an environmental flow value corresponding to 90% of the maximum reached by WUA curve, results seem acceptable for the Romaine River. Generally, this proposed fuzzy logic method seems suitable to model habitat availability for the three life stages, while also providing an estimate of uncertainty in salmon preferences.

  12. Understanding intratumor heterogeneity by combining genome analysis and mathematical modeling.

    Science.gov (United States)

    Niida, Atsushi; Nagayama, Satoshi; Miyano, Satoru; Mimori, Koshi

    2018-04-01

    Cancer is composed of multiple cell populations with different genomes. This phenomenon called intratumor heterogeneity (ITH) is supposed to be a fundamental cause of therapeutic failure. Therefore, its principle-level understanding is a clinically important issue. To achieve this goal, an interdisciplinary approach combining genome analysis and mathematical modeling is essential. For example, we have recently performed multiregion sequencing to unveil extensive ITH in colorectal cancer. Moreover, by employing mathematical modeling of cancer evolution, we demonstrated that it is possible that this ITH is generated by neutral evolution. In this review, we introduce recent advances in a research field related to ITH and also discuss strategies for exploiting novel findings on ITH in a clinical setting. © 2018 The Authors. Cancer Science published by John Wiley & Sons Australia, Ltd on behalf of Japanese Cancer Association.

  13. Physically-based modelling of polycrystalline semiconductor devices

    International Nuclear Information System (INIS)

    Lee, S.

    2000-01-01

    Thin-film technology using polycrystalline semiconductors has been widely applied to active-matrix-addressed liquid crystal displays (AMLCDs) where thin-film transistors act as digital pixel switches. Research and development is in progress to integrate the driver circuits around the peripheral of the display, resulting in significant cost reduction of connections between rows and columns and the peripheral circuitry. For this latter application, where for instance it is important to control the greyscale voltage level delivered to the pixel, an understanding of device behaviour is required so that models can be developed for analogue circuit simulation. For this purpose, various analytical models have been developed based on that of Seto who considered the effect of monoenergetic trap states and grain boundaries in polycrystalline materials but not the contribution of the grains to the electrical properties. The principal aim of this thesis is to describe the use of a numerical device simulator (ATLAS) as a tool to investigate the physics of the trapping process involved in the device operation, which additionally takes into account the effect of multienergetic trapping levels and the contribution of the grain into the modelling. A study of the conventional analytical models is presented, and an alternative approach is introduced which takes into account the grain regions to enhance the accuracy of the analytical modelling. A physically-based discrete-grain-boundary model and characterisation method are introduced to study the effects of the multienergetic trap states on the electrical characteristics of poly-TFTs using CdSe devices as the experimental example, and the electrical parameters such as the density distribution of the trapping states are extracted. The results show excellent agreement between the simulation and experimental data. The limitations of this proposed physical model are also studied and discussed. (author)

  14. Thermal modeling: at the crossroads of several subjects of physics

    International Nuclear Information System (INIS)

    1997-01-01

    The modeling of thermal phenomena is of prime importance for the dimensioning of industrial facilities. However, the understanding of thermal processes requires to refer to other subjects of physics like electromagnetism, matter transformation, fluid mechanics, chemistry etc.. The aim of this workshop organized by the industrial electro-thermal engineering section of the French society of thermal engineers is to take stock of current or forthcoming advances in the coupling of thermal engineering codes with electromagnetic, fluid mechanics, chemical and mechanical engineering codes. The modeling of phenomena remains the essential link between the laboratory research of new processes and their industrial developments. From the 9 talks given during this workshop, 2 of them deal with thermal processes in nuclear reactors and fall into the INIS scope and the others concern the modeling of industrial heating or electrical processes and were selected for ETDE. (J.S.)

  15. Graphene growth process modeling: a physical-statistical approach

    Science.gov (United States)

    Wu, Jian; Huang, Qiang

    2014-09-01

    As a zero-band semiconductor, graphene is an attractive material for a wide variety of applications such as optoelectronics. Among various techniques developed for graphene synthesis, chemical vapor deposition on copper foils shows high potential for producing few-layer and large-area graphene. Since fabrication of high-quality graphene sheets requires the understanding of growth mechanisms, and methods of characterization and control of grain size of graphene flakes, analytical modeling of graphene growth process is therefore essential for controlled fabrication. The graphene growth process starts with randomly nucleated islands that gradually develop into complex shapes, grow in size, and eventually connect together to cover the copper foil. To model this complex process, we develop a physical-statistical approach under the assumption of self-similarity during graphene growth. The growth kinetics is uncovered by separating island shapes from area growth rate. We propose to characterize the area growth velocity using a confined exponential model, which not only has clear physical explanation, but also fits the real data well. For the shape modeling, we develop a parametric shape model which can be well explained by the angular-dependent growth rate. This work can provide useful information for the control and optimization of graphene growth process on Cu foil.

  16. Understanding performance properties of chemical engines under a trade-off optimization: Low-dissipation versus endoreversible model

    Science.gov (United States)

    Tang, F. R.; Zhang, Rong; Li, Huichao; Li, C. N.; Liu, Wei; Bai, Long

    2018-05-01

    The trade-off criterion is used to systemically investigate the performance features of two chemical engine models (the low-dissipation model and the endoreversible model). The optimal efficiencies, the dissipation ratios, and the corresponding ratios of the dissipation rates for two models are analytically determined. Furthermore, the performance properties of two kinds of chemical engines are precisely compared and analyzed, and some interesting physics is revealed. Our investigations show that the certain universal equivalence between two models is within the framework of the linear irreversible thermodynamics, and their differences are rooted in the different physical contexts. Our results can contribute to a precise understanding of the general features of chemical engines.

  17. The Comparative Effectiveness of Physical, Virtual, and Virtual-Physical Manipulatives on Third-Grade Students' Science Achievement and Conceptual Understanding of Evaporation and Condensation

    Science.gov (United States)

    Wang, Tzu-Ling; Tseng, Yi-Kuan

    2018-01-01

    The purpose of this study was to investigate the relative effectiveness of experimenting with physical manipulatives alone, virtual manipulatives alone, and virtual preceding physical manipulatives (combination environment) on third-grade students' science achievement and conceptual understanding in the domain of state changes of water, focusing…

  18. A Multi-physics Approach to Understanding Low Porosity Soils and Reservoir Rocks

    Science.gov (United States)

    Prasad, M.; Mapeli, C.; Livo, K.; Hasanov, A.; Schindler, M.; Ou, L.

    2017-12-01

    We present recent results on our multiphysics approach to rock physics. Thus, we evaluate geophysical measurements by simultaneously measuring petrophysical properties or imaging strains. In this paper, we present simultaneously measured acoustic and electrical anisotropy data as functions of pressure. Similarly, we present strains and strain localization images simultaneously acquired with acoustic measurements as well as NMR T2 relaxations on pressurized fluids as well as rocks saturated with these pressurized fluids. Such multiphysics experiments allow us to constrain and assign appropriate causative mechanisms to development rock physics models. They also allow us to decouple various effects, for example, fluid versus pressure, on geophysical measurements. We show applications towards reservoir characterization as well as CO2 sequestration applications.

  19. A Holoinformational Model of the Physical Observer

    Science.gov (United States)

    di Biase, Francisco

    2013-09-01

    The author proposes a holoinformational view of the observer based, on the holonomic theory of brain/mind function and quantum brain dynamics developed by Karl Pribram, Sir John Eccles, R.L. Amoroso, Hameroff, Jibu and Yasue, and in the quantumholographic and holomovement theory of David Bohm. This conceptual framework is integrated with nonlocal information properties of the Quantum Field Theory of Umesawa, with the concept of negentropy, order, and organization developed by Shannon, Wiener, Szilard and Brillouin, and to the theories of self-organization and complexity of Prigogine, Atlan, Jantsch and Kauffman. Wheeler's "it from bit" concept of a participatory universe, and the developments of the physics of information made by Zureck and others with the concepts of statistical entropy and algorithmic entropy, related to the number of bits being processed in the mind of the observer are also considered. This new synthesis gives a self-organizing quantum nonlocal informational basis for a new model of awareness in a participatory universe. In this synthesis, awareness is conceived as meaningful quantum nonlocal information interconnecting the brain and the cosmos, by a holoinformational unified field (integrating nonlocal holistic (quantum) and local (Newtonian). We propose that the cosmology of the physical observer is this unified nonlocal quantum-holographic cosmos manifesting itself through awareness, interconnected in a participatory holistic and indivisible way the human mind-brain to all levels of the self-organizing holographic anthropic multiverse.

  20. Model unspecific search for new physics in pp collisions

    International Nuclear Information System (INIS)

    Malhotra, Shivali

    2013-01-01

    The model-independent analysis systematically scans the data taken by Compact Muon Solenoid - CMS detector for deviations from the Standard Model (SM) predictions. This approach is sensitive to a variety of models for new physics due to the minimal theoretical bias i.e. without assumptions on specific models of new physics and covering a large phase space. Possible causes of the significant deviations could be insufficient understanding of the collision event generation or detector simulation, or indeed genuine new physics in the data. Thus the output of MUSiC must be seen as only the first, but important step in the potential discovery of new physics. To get the distinctive final states, events with at least one electron or muon are classified according to their content of reconstructed objects (muons, electrons, photons, jets and missing transverse energy) and sorted into event classes. A broad scan of three kinematic distributions (scalar sum of the transverse momentum, invariant mass of reconstructed objects and missing transverse energy) in those event classes is performed by identifying deviations from SM expectations, accounting for systematic uncertainties. A scanning algorithm determines the regions in the considered distributions where the measured data deviates most from the SM predictions. This search is sensitive to an excess as well as a deficit in the comparison of data and SM background. This approach has been applied to the CMS data and we have obtained the preliminary results. I will talk about the details of the analysis techniques, its implementation in analyzing CMS data, results obtained and the discussion on the discrepancy observed

  1. Understanding a High School Physics Teacher's Pedagogical Content Knowledge of Argumentation

    Science.gov (United States)

    Wang, Jianlan; Buck, Gayle A.

    2016-08-01

    Scientific argumentation is an important learning objective in science education. It is also an effective instructional approach to constructivist science learning. The implementation of argumentation in school settings requires science teachers, who are pivotal agents of transforming classroom practices, to develop sophisticated knowledge of argumentation. However, there is a lack of understanding about science teachers' knowledge of argumentation, especially the dialogic meaning of argumentation. In this case study, we closely examine a high school physics teacher's argumentation-related pedagogic content knowledge (PCK) in the context of dialogic argumentation. We synthesize the teacher's performed PCK from his argumentation practices and narrated PCK from his reflection on the argumentation practices, from which we summarize his PCK of argumentation from the perspectives of orientation, instructional strategies, students, curriculum, and assessment. Finally, we describe the teacher's perception and adaption of argumentation in his class. We also identity the barriers to argumentation implementation in this particular case and suggest solutions to overcome these barriers.

  2. Surface physics theoretical models and experimental methods

    CERN Document Server

    Mamonova, Marina V; Prudnikova, I A

    2016-01-01

    The demands of production, such as thin films in microelectronics, rely on consideration of factors influencing the interaction of dissimilar materials that make contact with their surfaces. Bond formation between surface layers of dissimilar condensed solids-termed adhesion-depends on the nature of the contacting bodies. Thus, it is necessary to determine the characteristics of adhesion interaction of different materials from both applied and fundamental perspectives of surface phenomena. Given the difficulty in obtaining reliable experimental values of the adhesion strength of coatings, the theoretical approach to determining adhesion characteristics becomes more important. Surface Physics: Theoretical Models and Experimental Methods presents straightforward and efficient approaches and methods developed by the authors that enable the calculation of surface and adhesion characteristics for a wide range of materials: metals, alloys, semiconductors, and complex compounds. The authors compare results from the ...

  3. Understanding the physics of magnetic nanoparticles and their applications in the biomedical field

    Science.gov (United States)

    Laha, Suvra Santa

    The study of magnetic nanoparticles is of great interest because of their potential uses in magnetic-recording, medical diagnostic and therapeutic applications. Additionally, they also offer an opportunity to understand the physics underlying the complex behavior exhibited by these materials. Two of the most important relaxation phenomena occurring in magnetic nanoparticles are superparamagnetic blocking and spin-glass-like freezing. In addition to features attributed to superparamagnetism, these nanoparticles can also exhibit magnetic relaxation effects at very low temperatures (≤ 50 K). Our studies suggest that all structural defects, and not just surface spins, are responsible for the low-temperature glass-like relaxation observed in many magnetic nanoparticles. The characteristic dipolar interaction energy existing in an ensemble of magnetic nanoparticles does not apparently depend on the average spacing between the nanoparticles but is likely to be strongly influenced by the fluctuations in the nanoparticle distribution. Our findings revealed that incorporating a small percentage of boron can stabilize the spinel structure in Mn 3O4 nanoparticles. We have also demonstrated that the dipolar interactions between the magnetic cores can be tuned by introducing non-magnetic nanoparticles. In particular, we studied the magnetic properties of Gd-doped Fe3O4 nanoparticles, a potential applicant for T1--T2 dual-modal MRI contrast agent. We have explored the interactions of BiFeO3 nanoparticles on live cells and the binding of FITC-conjugated Fe3O 4 nanoparticles with artificial lipid membranes to investigate these materials as candidates in medical imaging. Taken together, these studies have advanced our understanding of the fundamental physical principles that governs magnetism in magnetic materials with a focus on developing these nanoparticles for advanced biomedical applications. The materials developed and studied expand the repertoire of tools available for

  4. Mathematical models of physics problems (physics research and technology)

    CERN Document Server

    Anchordoqui, Luis Alfredo

    2013-01-01

    This textbook is intended to provide a foundation for a one-semester introductory course on the advanced mathematical methods that form the cornerstones of the hard sciences and engineering. The work is suitable for first year graduate or advanced undergraduate students in the fields of Physics, Astronomy and Engineering. This text therefore employs a condensed narrative sufficient to prepare graduate and advanced undergraduate students for the level of mathematics expected in more advanced graduate physics courses, without too much exposition on related but non-essential material. In contrast to the two semesters traditionally devoted to mathematical methods for physicists, the material in this book has been quite distilled, making it a suitable guide for a one-semester course. The assumption is that the student, once versed in the fundamentals, can master more esoteric aspects of these topics on his or her own if and when the need arises during the course of conducting research. The book focuses on two cor...

  5. Understanding Global Change: Frameworks and Models for Teaching Systems Thinking

    Science.gov (United States)

    Bean, J. R.; Mitchell, K.; Zoehfeld, K.; Oshry, A.; Menicucci, A. J.; White, L. D.; Marshall, C. R.

    2017-12-01

    The scientific and education communities must impart to teachers, students, and the public an understanding of how the various factors that drive climate and global change operate, and why the rates and magnitudes of these changes related to human perturbation of Earth system processes today are cause for deep concern. Even though effective educational modules explaining components of the Earth and climate system exist, interdisciplinary learning tools are necessary to conceptually link the causes and consequences of global changes. To address this issue, the Understanding Global Change Project at the University of California Museum of Paleontology (UCMP) at UC Berkeley developed an interdisciplinary framework that organizes global change topics into three categories: (1) causes of climate change, both human and non-human (e.g., burning of fossil fuels, deforestation, Earth's tilt and orbit), (2) Earth system processes that shape the way the Earth works (e.g., Earth's energy budget, water cycle), and (3) the measurable changes in the Earth system (e.g., temperature, precipitation, ocean acidification). To facilitate student learning about the Earth as a dynamic, interacting system, a website will provide visualizations of Earth system models and written descriptions of how each framework topic is conceptually linked to other components of the framework. These visualizations and textual summarizations of relationships and feedbacks in the Earth system are a unique and crucial contribution to science communication and education, informed by a team of interdisciplinary scientists and educators. The system models are also mechanisms by which scientists can communicate how their own work informs our understanding of the Earth system. Educators can provide context and relevancy for authentic datasets and concurrently can assess student understanding of the interconnectedness of global change phenomena. The UGC resources will be available through a web-based platform and

  6. Giant plasma membrane vesicles: models for understanding membrane organization.

    Science.gov (United States)

    Levental, Kandice R; Levental, Ilya

    2015-01-01

    The organization of eukaryotic membranes into functional domains continues to fascinate and puzzle cell biologists and biophysicists. The lipid raft hypothesis proposes that collective lipid interactions compartmentalize the membrane into coexisting liquid domains that are central to membrane physiology. This hypothesis has proven controversial because such structures cannot be directly visualized in live cells by light microscopy. The recent observations of liquid-liquid phase separation in biological membranes are an important validation of the raft hypothesis and enable application of the experimental toolbox of membrane physics to a biologically complex phase-separated membrane. This review addresses the role of giant plasma membrane vesicles (GPMVs) in refining the raft hypothesis and expands on the application of GPMVs as an experimental model to answer some of key outstanding problems in membrane biology. Copyright © 2015 Elsevier Inc. All rights reserved.

  7. The effect of Phet Simulation media for physics teacher candidate understanding on photoelectric effect concept

    Directory of Open Access Journals (Sweden)

    Supurwoko Supurwoko

    2017-02-01

    Full Text Available Indonesian new Curriculum for senior high school students required student-centered learning. One of the curriculum implementation constraint was the difficulty of providing learning media. PhET simulations media is one of the options that can help implementation of new curriculum on learning. However, the use of this media in Indonesia still needs to be studied comprehensively. The learning was conducted on students of physics education Study Program in sebelas maret university in 2013. The sample consisted of 62 students that was taking quantum physics course. The method that was used in the research was descriptive qualitative.  The method that was used in learning was demonstration’s method that used PhET media and accompanied by a question and answer and groups discussion. The data was collected using multiple choice test and interview through email. We found that any students still did not understand about photoelectric effect concept. They were confused when asked about the thick material and cross section of the targets as related with the regardless of electrons in the photoelectric effect event. Other than that, the concept of the waves as a particle and its relation with the kinetic energy of the electrons was not understood by most students.

  8. Simplified Physics Based Models Research Topical Report on Task #2

    Energy Technology Data Exchange (ETDEWEB)

    Mishra, Srikanta; Ganesh, Priya

    2014-10-31

    We present a simplified-physics based approach, where only the most important physical processes are modeled, to develop and validate simplified predictive models of CO2 sequestration in deep saline formation. The system of interest is a single vertical well injecting supercritical CO2 into a 2-D layered reservoir-caprock system with variable layer permeabilities. We use a set of well-designed full-physics compositional simulations to understand key processes and parameters affecting pressure propagation and buoyant plume migration. Based on these simulations, we have developed correlations for dimensionless injectivity as a function of the slope of fractional-flow curve, variance of layer permeability values, and the nature of vertical permeability arrangement. The same variables, along with a modified gravity number, can be used to develop a correlation for the total storage efficiency within the CO2 plume footprint. Similar correlations are also developed to predict the average pressure within the injection reservoir, and the pressure buildup within the caprock.

  9. Stochastic Spatial Models in Ecology: A Statistical Physics Approach

    Science.gov (United States)

    Pigolotti, Simone; Cencini, Massimo; Molina, Daniel; Muñoz, Miguel A.

    2017-11-01

    Ecosystems display a complex spatial organization. Ecologists have long tried to characterize them by looking at how different measures of biodiversity change across spatial scales. Ecological neutral theory has provided simple predictions accounting for general empirical patterns in communities of competing species. However, while neutral theory in well-mixed ecosystems is mathematically well understood, spatial models still present several open problems, limiting the quantitative understanding of spatial biodiversity. In this review, we discuss the state of the art in spatial neutral theory. We emphasize the connection between spatial ecological models and the physics of non-equilibrium phase transitions and how concepts developed in statistical physics translate in population dynamics, and vice versa. We focus on non-trivial scaling laws arising at the critical dimension D = 2 of spatial neutral models, and their relevance for biological populations inhabiting two-dimensional environments. We conclude by discussing models incorporating non-neutral effects in the form of spatial and temporal disorder, and analyze how their predictions deviate from those of purely neutral theories.

  10. The Effects on Students' Conceptual Understanding of Electric Circuits of Introducing Virtual Manipulatives within a Physical Manipulatives-Oriented Curriculum

    Science.gov (United States)

    Zacharia, Zacharias C.; de Jong, Ton

    2014-01-01

    This study investigates whether Virtual Manipulatives (VM) within a Physical Manipulatives (PM)-oriented curriculum affect conceptual understanding of electric circuits and related experimentation processes. A pre-post comparison study randomly assigned 194 undergraduates in an introductory physics course to one of five conditions: three…

  11. The Effectiveness of the Brain Based Teaching Approach in Enhancing Scientific Understanding of Newtonian Physics among Form Four Students

    Science.gov (United States)

    Saleh, Salmiza

    2012-01-01

    The aim of this study was to assess the effectiveness of Brain Based Teaching Approach in enhancing students' scientific understanding of Newtonian Physics in the context of Form Four Physics instruction. The technique was implemented based on the Brain Based Learning Principles developed by Caine & Caine (1991, 2003). This brain compatible…

  12. Understanding Housing Delays and Relocations Within the Housing First Model.

    Science.gov (United States)

    Zerger, Suzanne; Pridham, Katherine Francombe; Jeyaratnam, Jeyagobi; Hwang, Stephen W; O'Campo, Patricia; Kohli, Jaipreet; Stergiopoulos, Vicky

    2016-01-01

    This study explores factors contributing to delays and relocations during the implementation of the Housing First model in Toronto, Ontario. While interruptions in housing tenure are expected en route to recovery and housing stability, consumer and service provider views on finding and keeping housing remain largely unknown. In-person interviews and focus groups were conducted with 48 study participants, including 23 case managers or housing workers and 25 consumers. The following three factors contributed to housing delays and transfers: (1) the effectiveness of communication and collaboration among consumers and service providers, (2) consumer-driven preferences and ambivalence, and (3) provider prioritization of consumer choice over immediate housing access. Two strategies--targeted communications and consumer engagement in housing searches--supported the housing process. Several factors affect the timing and stability of housing. Communication between and among providers and consumers, and a shared understanding of consumer choice, can further support choice and recovery.

  13. Chemico-physical models of cometary atmospheres

    International Nuclear Information System (INIS)

    Huebner, W.F.; Keady, J.J.; Boice, D.C.; Schmidt, H.U.; Wegmann, R.

    1985-01-01

    Sublimation (vaporization) of the icy component of a cometary nucleus determines the initial composition of the coma gas as it streams outward and escapes. Photolytic reactions in the inner coma, escape of fast, light species such as atomic and molecular hydrogen, and solar wind interaction in the outer coma alter the chemical composition and the physical nature of the coma gas. Models that describe these interactions must include (1) chemical kinetics, (2) coma energy balance, (3) multifluid flow for the rapidly escaping light components, the heavier bulk fluid, and the plasma with separate temperatures for electrons and the remainder of the gas, (4) transition from a collision dominated inner region to free molecular flow of neutrals in the outer region, (5) pickup of cometary ions by the solar wind, (6) counter and cross streaming of neutrals with respect to the plasma which outside of the contact surface also contains solar wind ions, and (7) magnetic fields carried by the solar wind. Progress on such models is described and results including velocity, temperature, and number density profiles for important chemical species are presented and compared with observations

  14. Physical model of optical inhomogeneities of water

    Science.gov (United States)

    Shybanov, E. B.

    2017-11-01

    The paper is devoted to theoretical aspects of the light scattering of water that does not contain suspended particles. To be consistent with current physical point of view the water as far as any liquid is regarded as a complex unstable nonergodic media. It was proposed that at fixed time the water as a condensed medium had global inhomogeneities similar to linear and planar defects in a solid. Anticipated own global inhomogeneities of water have been approximated by the system randomly distributed spherical clusters filling the entire water bulk. An analytical expression for the single scattered light has been derived. The formula simultaneously describes both the high anisotropy of light scattering and the high degree of polarization which one close to those for molecular scattering. It is shown that at general angles there is a qualitative coincidence with the two-component Kopelevich's model for the light scattering by marine particles. On the contrary towards to forwards angles the spectral law becomes much more prominent i.e. it corresponds to results for model of optically soft particles.

  15. Understanding physical (in-) activity, overweight, and obesity in childhood: Effects of congruence between physical self-concept and motor competence.

    Science.gov (United States)

    Utesch, T; Dreiskämper, D; Naul, R; Geukes, K

    2018-04-12

    Both the physical self-concept and actual motor competence are important for healthy future physical activity levels and consequently decrease overweight and obesity in childhood. However, children scoring high on motor competence do not necessarily report high levels of physical self-concept and vice versa, resulting in respective (in-) accuracy also referred to as (non-) veridicality. This study examines whether children's accuracy of physical self-concept is a meaningful predictive factor for their future physical activity. Motor competence, physical self-concept and physical activity were assessed in 3 rd grade and one year later in 4 th grade. Children's weight status was categorized based on WHO recommendations. Polynomial regression with Response surface analyses were conducted with a quasi-DIF approach examining moderating weight status effects. Analyses revealed that children with higher motor competence levels and higher self-perceptions show greater physical activity. Importantly, children who perceive their motor competence more accurately (compared to less) show more future physical activity. This effect is strong for underweight and overweight/obese children, but weak for normal weight children. This study indicates that an accurate self-perception of motor competence fosters future physical activity beyond single main effects, respectively. Hence, the promotion of actual motor competence should be linked with the respective development of accurate self-knowledge.

  16. Improved understanding of physics processes in pedestal structure, leading to improved predictive capability for ITER

    International Nuclear Information System (INIS)

    Groebner, R.J.; Snyder, P.B.; Leonard, A.W.; Chang, C.S.; Maingi, R.; Boyle, D.P.; Diallo, A.; Hughes, J.W.; Davis, E.M.; Ernst, D.R.; Landreman, M.; Xu, X.Q.; Boedo, J.A.; Cziegler, I.; Diamond, P.H.; Eldon, D.P.; Callen, J.D.; Canik, J.M.; Elder, J.D.; Fulton, D.P.

    2013-01-01

    Joint experiment/theory/modelling research has led to increased confidence in predictions of the pedestal height in ITER. This work was performed as part of a US Department of Energy Joint Research Target in FY11 to identify physics processes that control the H-mode pedestal structure. The study included experiments on C-Mod, DIII-D and NSTX as well as interpretation of experimental data with theory-based modelling codes. This work provides increased confidence in the ability of models for peeling–ballooning stability, bootstrap current, pedestal width and pedestal height scaling to make correct predictions, with some areas needing further work also being identified. A model for pedestal pressure height has made good predictions in existing machines for a range in pressure of a factor of 20. This provides a solid basis for predicting the maximum pedestal pressure height in ITER, which is found to be an extrapolation of a factor of 3 beyond the existing data set. Models were studied for a number of processes that are proposed to play a role in the pedestal n e and T e profiles. These processes include neoclassical transport, paleoclassical transport, electron temperature gradient turbulence and neutral fuelling. All of these processes may be important, with the importance being dependent on the plasma regime. Studies with several electromagnetic gyrokinetic codes show that the gradients in and on top of the pedestal can drive a number of instabilities. (paper)

  17. Planetary nebulae: understanding the physical and chemical evolution of dying stars.

    Science.gov (United States)

    Weinberger, R; Kerber, F

    1997-05-30

    Planetary nebulae are one of the few classes of celestial objects that are active in every part of the electromagnetic spectrum. These fluorescing and often dusty expanding gaseous envelopes were recently found to be quite complex in their dynamics and morphology, but refined theoretical models can account for these discoveries. Great progress was also made in understanding the mechanisms that shape the nebulae and the spectra of their central stars. In addition, applications for planetary nebulae have been worked out; for example, they have been used as standard candles for long-range distances and as tracers of the enigmatic dark matter.

  18. A Structural Equation Model of Expertise in College Physics

    Science.gov (United States)

    Taasoobshirazi, Gita; Carr, Martha

    2009-01-01

    A model of expertise in physics was tested on a sample of 374 college students in 2 different level physics courses. Structural equation modeling was used to test hypothesized relationships among variables linked to expert performance in physics including strategy use, pictorial representation, categorization skills, and motivation, and these…

  19. A Structural Equation Model of Conceptual Change in Physics

    Science.gov (United States)

    Taasoobshirazi, Gita; Sinatra, Gale M.

    2011-01-01

    A model of conceptual change in physics was tested on introductory-level, college physics students. Structural equation modeling was used to test hypothesized relationships among variables linked to conceptual change in physics including an approach goal orientation, need for cognition, motivation, and course grade. Conceptual change in physics…

  20. The Parkinson's experience of group physical activity: Understanding social support, social comparison, physical self-perceptions, and posttraumatic growth

    OpenAIRE

    Sheehy, Tammy L

    2014-01-01

    Group physical activity programs for clinical populations can provide opportunities for adaptive social interactions, improving perceptions of competence, and may facilitate posttraumatic growth (positive psychological changes resulting from traumatic life experiences). Therefore, the purpose of this study was to examine how people with Parkinson's experience social interactions and physical challenges in a group physical activity program, and to investigate what role they think those experie...

  1. Physical modelling and testing in environmental geotechnics

    International Nuclear Information System (INIS)

    Garnier, J.; Thorel, L.; Haza, E.

    2000-01-01

    The preservation of natural environment has become a major concern, which affects nowadays a wide range of professionals from local communities administrators to natural resources managers (water, wildlife, flora, etc) and, in the end, to the consumers that we all are. Although totally ignored some fifty years ago, environmental geotechnics has become an emergent area of study and research which borders on the traditional domains, with which the geo-technicians are confronted (soil and rock mechanics, engineering geology, natural and anthropogenic risk management). Dedicated to experimental approaches (in-situ investigations and tests, laboratory tests, small-scale model testing), the Symposium fits in with the geotechnical domains of environment and transport of soil pollutants. These proceedings report some progress of developments in measurement techniques and studies of transport of pollutants in saturated and unsaturated soils in order to improve our understanding of such phenomena within multiphase environments. Experimental investigations on decontamination and isolation methods for polluted soils are discussed. The intention is to assess the impact of in-situ and laboratory tests, as well as small-scale model testing, on engineering practice. One paper is analysed in INIS data base for its specific interest in nuclear industry. The other ones, concerning the energy, are analyzed in ETDE data base

  2. Physical modelling and testing in environmental geotechnics

    Energy Technology Data Exchange (ETDEWEB)

    Garnier, J.; Thorel, L.; Haza, E. [Laboratoire Central des Ponts et Chaussees a Nantes, 44 - Nantes (France)

    2000-07-01

    The preservation of natural environment has become a major concern, which affects nowadays a wide range of professionals from local communities administrators to natural resources managers (water, wildlife, flora, etc) and, in the end, to the consumers that we all are. Although totally ignored some fifty years ago, environmental geotechnics has become an emergent area of study and research which borders on the traditional domains, with which the geo-technicians are confronted (soil and rock mechanics, engineering geology, natural and anthropogenic risk management). Dedicated to experimental approaches (in-situ investigations and tests, laboratory tests, small-scale model testing), the Symposium fits in with the geotechnical domains of environment and transport of soil pollutants. These proceedings report some progress of developments in measurement techniques and studies of transport of pollutants in saturated and unsaturated soils in order to improve our understanding of such phenomena within multiphase environments. Experimental investigations on decontamination and isolation methods for polluted soils are discussed. The intention is to assess the impact of in-situ and laboratory tests, as well as small-scale model testing, on engineering practice. One paper has been analyzed in INIS data base for its specific interest in nuclear industry.

  3. Physical Basis for Interfacial Traction-Separation Models

    International Nuclear Information System (INIS)

    Neville R. Moody

    2002-01-01

    Many weapon components contain interfaces between dissimilar materials where cracks can initiate and cause failure. In recent years many researchers in the fracture community have adopted a cohesive zone model for simulating crack propagation (based upon traction-separation relations) Sandia is implementing this model in its ASCI codes. There is, however, one important obstacle to using a cohesive zone modeling approach. At the present time traction-separation relations are chosen in an ad hoc manner. The goal of the present work is to determine a physical basis for Traction-Separation (T-U) relations. This report presents results of a program aimed at determining the dependence of such relations on adhesive and bulk properties. The work focused on epoxy/solid interfaces, although the approach is applicable to a broad range of materials. Asymmetric double cantilevered beam and free surface film nanoindentation fracture toughness tests were used to generate a unique set of data spanning length scales, applied mode mixities, and yield (plastic) zone constraint. The crucial roles of crack tip plastic zone size and interfacial adhesion were defined by varying epoxy layer thickness and using coupling agents or special self-assembled monolayers in preparing the samples. The nature of the yield zone was probed in collaborative experiments run at the Advanced Photon Source. This work provides an understanding of the major phenomena governing polymer/solid interfacial fracture and identifies the essential features that must be incorporated in a T-U based cohesive zone failure model. We believe that models using physically based T-U relations provide a more accurate and widely applicable description of interface cracking than models using ad hoc relations. Furthermore, these T-U relations provide an essential tool for using models to tailor interface properties to meet design needs

  4. Understanding H isotope adsorption and absorption of Al-alloys using modeling and experiments (LDRD: #165724)

    Energy Technology Data Exchange (ETDEWEB)

    Ward, Donald K. [Sandia National Laboratories (SNL-CA), Livermore, CA (United States); Zhou, Xiaowang [Sandia National Laboratories (SNL-CA), Livermore, CA (United States); Karnesky, Richard A. [Sandia National Laboratories (SNL-CA), Livermore, CA (United States); Kolasinski, Robert [Sandia National Laboratories (SNL-CA), Livermore, CA (United States); Foster, Michael E. [Sandia National Laboratories (SNL-CA), Livermore, CA (United States); Thurmer, Konrad [Sandia National Laboratories (SNL-CA), Livermore, CA (United States); Chao, Paul [Carnegie Mellon University, Pittsburgh, PA (United States); Epperly, Ethan Nicholas [Livermore Valley Charter Preparatory High School, Livermore, CA (United States); Zimmerman, Jonathan A. [Sandia National Laboratories (SNL-CA), Livermore, CA (United States); Wong, Bryan M. [Univ. of California, Riverside, CA (United States); Sills, Ryan B. [Sandia National Laboratories (SNL-CA), Livermore, CA (United States)

    2015-09-01

    Current austenitic stainless steel storage reservoirs for hydrogen isotopes (e.g. deuterium and tritium) have performance and operational life-limiting interactions (e.g. embrittlement) with H-isotopes. Aluminum alloys (e.g.AA2219), alternatively, have very low H-isotope solubilities, suggesting high resistance towards aging vulnerabilities. This report summarizes the work performed during the life of the Lab Directed Research and Development in the Nuclear Weapons investment area (165724), and provides invaluable modeling and experimental insights into the interactions of H isotopes with surfaces and bulk AlCu-alloys. The modeling work establishes and builds a multi-scale framework which includes: a density functional theory informed bond-order potential for classical molecular dynamics (MD), and subsequent use of MD simulations to inform defect level dislocation dynamics models. Furthermore, low energy ion scattering and thermal desorption spectroscopy experiments are performed to validate these models and add greater physical understanding to them.

  5. Rock Burst Mechanics: Insight from Physical and Mathematical Modelling

    Directory of Open Access Journals (Sweden)

    J. Vacek

    2008-01-01

    Full Text Available Rock burst processes in mines are studied by many groups active in the field of geomechanics. Physical and mathematical modelling can be used to better understand the phenomena and mechanisms involved in the bursts. In the present paper we describe both physical and mathematical models of a rock burst occurring in a gallery of a coal mine.For rock bursts (also called bumps to occur, the rock has to possess certain particular rock burst properties leading to accumulation of energy and the potential to release this energy. Such materials may be brittle, or the rock burst may arise at the interfacial zones of two parts of the rock, which have principally different material properties (e.g. in the Poíbram uranium mines.The solution is based on experimental and mathematical modelling. These two methods have to allow the problem to be studied on the basis of three presumptions:· the solution must be time dependent,· the solution must allow the creation of cracks in the rock mass,· the solution must allow an extrusion of rock into an open space (bump effect. 

  6. Hydrogeological modelling as a tool for understanding rockslides evolution

    Science.gov (United States)

    Crosta, Giovanni B.; De Caro, Mattia; Frattini, Paolo; Volpi, Giorgio

    2015-04-01

    construction of the models, in particular the partition of the slope in different sectors with different hydraulic conductivities, are coherent with the geological, structural, hydrological and hydrogeological field and laboratory data. The sensitivity analysis shows that the hydraulic conductivity of some slope sectors (e.g. morphostructures, compressed or relaxed slope-toe, basal shear band) strongly influence the water table position and evolution. In transient models, the values of specific storage coefficient play a major control on the amplitude of groundwater level fluctuations, deriving from snowmelt or induced reservoir level rise. The calibrated groundwater flow-models are consistent with groundwater levels measured in the proximity of the piezometers aligned along the sections. The two examples can be considered important for a more advanced understanding of the evolution of rockslides and suggest the required set of data and modelling approaches both for seasonal and long term slope stability analyses. The use of the results of such analyses is reported, for both the case studies, in a companion abstract in session 3.7 where elasto-visco-plastic rheologies have been adopted for the shear band materials to replicate the available displacement time-series.

  7. An Interdisciplinary Undergraduate Space Physics Course: Understanding the Process of Science Through One Field's Colorful History

    Science.gov (United States)

    Lopez, Ramon E.

    1996-01-01

    Science education in this country is in its greatest period of ferment since the post-Sputnik frenzy a generation ago. In that earlier time, however, educators' emphasis was on producing more scientists and engineers. Today we recognize that all Americans need a good science background. The ability to observe, measure, think quantitatively, and reach logical conclusions based on available evidence is a set of skills that everyone entering the workforce needs to acquire if our country is to be competitive in a global economy. Moreover, as public policy increasingly crystallizes around scientific issues, it is critical that citizens be educated in science so that they may provide informed debate and on these issues. In order to develop this idea more fully, I proposed to teach a historically based course about space physics as an honors course at the University of Maryland-College Park (UMCP). The honors program at UMCP was established to foster broad-based undergraduate courses that utilize innovative teaching techniques to provide exemplary education to a select group of students. I designed an introductory course that would have four basic goals: to acquaint students with geomagnetic and auroral phenomena and their relationship to the space environment; to examine issues related to the history of science using the evolution of the field as an example; to develop familiarity with basic skills such as describing and interpreting observations, analyzing scientific papers, and communicating the results of their own research; and to provide some understanding of basic physics, especially those aspect that play a role in the near-earth space environment.

  8. Understanding system disturbance and ecosystem services in restored saltmarshes: Integrating physical and biogeochemical processes

    Science.gov (United States)

    Spencer, K. L.; Harvey, G. L.

    2012-06-01

    Coastal saltmarsh ecosystems occupy only a small percentage of Earth's land surface, yet contribute a wide range of ecosystem services that have significant global economic and societal value. These environments currently face significant challenges associated with climate change, sea level rise, development and water quality deterioration and are consequently the focus of a range of management schemes. Increasingly, soft engineering techniques such as managed realignment (MR) are being employed to restore and recreate these environments, driven primarily by the need for habitat (re)creation and sustainable coastal flood defence. Such restoration schemes also have the potential to provide additional ecosystem services including climate regulation and waste processing. However, these sites have frequently been physically impacted by their previous land use and there is a lack of understanding of how this 'disturbance' impacts the delivery of ecosystem services or of the complex linkages between ecological, physical and biogeochemical processes in restored systems. Through the exploration of current data this paper determines that hydrological, geomorphological and hydrodynamic functioning of restored sites may be significantly impaired with respects to natural 'undisturbed' systems and that links between morphology, sediment structure, hydrology and solute transfer are poorly understood. This has consequences for the delivery of seeds, the provision of abiotic conditions suitable for plant growth, the development of microhabitats and the cycling of nutrients/contaminants and may impact the delivery of ecosystem services including biodiversity, climate regulation and waste processing. This calls for a change in our approach to research in these environments with a need for integrated, interdisciplinary studies over a range of spatial and temporal scales incorporating both intensive and extensive research design.

  9. Modeling Patient Treatment With Medical Records: An Abstraction Hierarchy to Understand User Competencies and Needs.

    Science.gov (United States)

    St-Maurice, Justin D; Burns, Catherine M

    2017-07-28

    Health care is a complex sociotechnical system. Patient treatment is evolving and needs to incorporate the use of technology and new patient-centered treatment paradigms. Cognitive work analysis (CWA) is an effective framework for understanding complex systems, and work domain analysis (WDA) is useful for understanding complex ecologies. Although previous applications of CWA have described patient treatment, due to their scope of work patients were previously characterized as biomedical machines, rather than patient actors involved in their own care. An abstraction hierarchy that characterizes patients as beings with complex social values and priorities is needed. This can help better understand treatment in a modern approach to care. The purpose of this study was to perform a WDA to represent the treatment of patients with medical records. The methods to develop this model included the analysis of written texts and collaboration with subject matter experts. Our WDA represents the ecology through its functional purposes, abstract functions, generalized functions, physical functions, and physical forms. Compared with other work domain models, this model is able to articulate the nuanced balance between medical treatment, patient education, and limited health care resources. Concepts in the analysis were similar to the modeling choices of other WDAs but combined them in as a comprehensive, systematic, and contextual overview. The model is helpful to understand user competencies and needs. Future models could be developed to model the patient's domain and enable the exploration of the shared decision-making (SDM) paradigm. Our work domain model links treatment goals, decision-making constraints, and task workflows. This model can be used by system developers who would like to use ecological interface design (EID) to improve systems. Our hierarchy is the first in a future set that could explore new treatment paradigms. Future hierarchies could model the patient as a

  10. "If I had to do it, then I would": Understanding early middle school students' perceptions of physics and physics-related careers by gender

    Science.gov (United States)

    Dare, Emily A.; Roehrig, Gillian H.

    2016-12-01

    [This paper is part of the Focused Collection on Gender in Physics.] This study examined the perceptions of 6th grade middle school students regarding physics and physics-related careers. The overarching goal of this work was to understand similarities and differences between girls' and boys' perceptions surrounding physics and physics-related careers as part of a long-term effort to increase female interest and representation in this particular field of science. A theoretical framework based on the literature of girl-friendly and integrated STEM instructional strategies guided this work to understand how instructional strategies may influence and relate to students' perceptions. This convergent parallel mixed-methods study used a survey and focus group interviews to understand similarities and differences between girls' and boys' perceptions. Our findings indicate very few differences between girls and boys, but show that boys are more interested in the physics-related career of engineering. While girls are just as interested in science class as their male counterparts, they highly value the social aspect that often accompanies hands-on group activities. These findings shed light on how K-12 science reform efforts might help to increase the number of women pursuing careers related to physics.

  11. “If I had to do it, then I would”: Understanding early middle school students’ perceptions of physics and physics-related careers by gender

    Directory of Open Access Journals (Sweden)

    Emily A. Dare

    2016-08-01

    Full Text Available [This paper is part of the Focused Collection on Gender in Physics.] This study examined the perceptions of 6th grade middle school students regarding physics and physics-related careers. The overarching goal of this work was to understand similarities and differences between girls’ and boys’ perceptions surrounding physics and physics-related careers as part of a long-term effort to increase female interest and representation in this particular field of science. A theoretical framework based on the literature of girl-friendly and integrated STEM instructional strategies guided this work to understand how instructional strategies may influence and relate to students’ perceptions. This convergent parallel mixed-methods study used a survey and focus group interviews to understand similarities and differences between girls’ and boys’ perceptions. Our findings indicate very few differences between girls and boys, but show that boys are more interested in the physics-related career of engineering. While girls are just as interested in science class as their male counterparts, they highly value the social aspect that often accompanies hands-on group activities. These findings shed light on how K-12 science reform efforts might help to increase the number of women pursuing careers related to physics.

  12. Nuclear planetology: understanding planetary mantle and crust formation in the light of nuclear and particle physics

    Science.gov (United States)

    Roller, Goetz

    2017-04-01

    The Hertzsprung-Russell (HR) diagram is one of the most important diagrams in astronomy. In a HR diagram, the luminosity of stars and/or stellar remnants (white dwarf stars, WD's), relative to the luminosity of the sun, is plotted versus their surface temperatures (Teff). The Earth shows a striking similarity in size (radius ≈ 6.371 km) and Teff of its outer core surface (Teff ≈ 3800 K at the core-mantle-boundary) with old WD's (radius ≈ 6.300 km) like WD0346+246 (Teff ≈ 3820 K after ≈ 12.7 Ga [1]), which plot in the HR diagram close to the low-mass extension of the stellar population or main sequence. In the light of nuclear planetology [2], Earth-like planets are regarded as old, down-cooled and differentiated black dwarfs (Fe-C BLD's) after massive decompression, the most important nuclear reactions involved being 56Fe(γ,α)52Cr (etc.), possibly responsible for extreme terrestrial glaciations events ("snowball" Earth), together with (γ,n), (γ,p) and fusion reactions like 12C(α,γ)16O. The latter reaction might have caused oxidation of the planet from inside out. Nuclear planetology is a new research field, tightly constrained by a coupled 187Re-232Th-238U systematics [3-5]. By means of nuclear/quantum physics and taking the theory of relativity into account, it aims at understanding the thermal and chemical evolution of Fe-C BLD's after gravitational contraction (e.g. Mercury) or Fermi-pressure controlled collapse (e.g. Earth) events after massive decompression, leading possibly to an r-process event, towards the end of their cooling period [2]. So far and based upon 187Re-232Th-238U nuclear geochronometry, the Fe-C BLD hypothesis can successfully explain the global terrestrial MORB 232Th/238U signature [5]. Thus, it may help to elucidate the DM (depleted mantle), EMI (enriched mantle 1), EMII (enriched mantle 2) or HIMU (high U/Pb) reservoirs [6], and the 187Os/188Os isotopic dichotomy in Archean magmatic rocks and sediments [7]. Here I present a

  13. Evolving Understanding of Antarctic Ice-Sheet Physics and Ambiguity in Probabilistic Sea-Level Projections

    Science.gov (United States)

    Kopp, Robert E.; DeConto, Robert M.; Bader, Daniel A.; Hay, Carling C.; Horton, Radley M.; Kulp, Scott; Oppenheimer, Michael; Pollard, David; Strauss, Benjamin H.

    2017-12-01

    Mechanisms such as ice-shelf hydrofracturing and ice-cliff collapse may rapidly increase discharge from marine-based ice sheets. Here, we link a probabilistic framework for sea-level projections to a small ensemble of Antarctic ice-sheet (AIS) simulations incorporating these physical processes to explore their influence on global-mean sea-level (GMSL) and relative sea-level (RSL). We compare the new projections to past results using expert assessment and structured expert elicitation about AIS changes. Under high greenhouse gas emissions (Representative Concentration Pathway [RCP] 8.5), median projected 21st century GMSL rise increases from 79 to 146 cm. Without protective measures, revised median RSL projections would by 2100 submerge land currently home to 153 million people, an increase of 44 million. The use of a physical model, rather than simple parameterizations assuming constant acceleration of ice loss, increases forcing sensitivity: overlap between the central 90% of simulations for 2100 for RCP 8.5 (93-243 cm) and RCP 2.6 (26-98 cm) is minimal. By 2300, the gap between median GMSL estimates for RCP 8.5 and RCP 2.6 reaches >10 m, with median RSL projections for RCP 8.5 jeopardizing land now occupied by 950 million people (versus 167 million for RCP 2.6). The minimal correlation between the contribution of AIS to GMSL by 2050 and that in 2100 and beyond implies current sea-level observations cannot exclude future extreme outcomes. The sensitivity of post-2050 projections to deeply uncertain physics highlights the need for robust decision and adaptive management frameworks.

  14. Evolving Understanding of Antarctic Ice-Sheet Physics and Ambiguity in Probabilistic Sea-Level Projections

    Science.gov (United States)

    Kopp, Robert E.; DeConto, Robert M.; Bader, Daniel A.; Hay, Carling C.; Horton, Radley M.; Kulp, Scott; Oppenheimer, Michael; Pollard, David; Strauss, Benjamin

    2017-01-01

    Mechanisms such as ice-shelf hydrofracturing and ice-cliff collapse may rapidly increase discharge from marine-based ice sheets. Here, we link a probabilistic framework for sea-level projections to a small ensemble of Antarctic ice-sheet (AIS) simulations incorporating these physical processes to explore their influence on global-mean sea-level (GMSL) and relative sea-level (RSL). We compare the new projections to past results using expert assessment and structured expert elicitation about AIS changes. Under high greenhouse gas emissions (Representative Concentration Pathway [RCP] 8.5), median projected 21st century GMSL rise increases from 79 to 146 cm. Without protective measures, revised median RSL projections would by 2100 submerge land currently home to 153 million people, an increase of 44 million. The use of a physical model, rather than simple parameterizations assuming constant acceleration of ice loss, increases forcing sensitivity: overlap between the central 90% of simulations for 2100 for RCP 8.5 (93-243 cm) and RCP 2.6 (26-98 cm) is minimal. By 2300, the gap between median GMSL estimates for RCP 8.5 and RCP 2.6 reaches >10 m, with median RSL projections for RCP 8.5 jeopardizing land now occupied by 950 million people (versus 167 million for RCP 2.6). The minimal correlation between the contribution of AIS to GMSL by 2050 and that in 2100 and beyond implies current sea-level observations cannot exclude future extreme outcomes. The sensitivity of post-2050 projections to deeply uncertain physics highlights the need for robust decision and adaptive management frameworks.

  15. Four discourse models of physics teacher education

    OpenAIRE

    Larsson, Johanna; Airey, John

    2017-01-01

    In Sweden, as in many other countries, the education of high-school physics teachers is typically carried out in three different environments; the education department, the physics department and school itself during teaching practice. Trainee physics teachers are in the process of building their professional identity as they move between these three environments. Although much has been written about teacher professional identity (see overview in Beijaard, Meijer, & Verloop, 2004) little ...

  16. Effective models of new physics at the Large Hadron Collider

    International Nuclear Information System (INIS)

    Llodra-Perez, J.

    2011-07-01

    With the start of the Large Hadron Collider runs, in 2010, particle physicists will be soon able to have a better understanding of the electroweak symmetry breaking. They might also answer to many experimental and theoretical open questions raised by the Standard Model. Surfing on this really favorable situation, we will first present in this thesis a highly model-independent parametrization in order to characterize the new physics effects on mechanisms of production and decay of the Higgs boson. This original tool will be easily and directly usable in data analysis of CMS and ATLAS, the huge generalist experiments of LHC. It will help indeed to exclude or validate significantly some new theories beyond the Standard Model. In another approach, based on model-building, we considered a scenario of new physics, where the Standard Model fields can propagate in a flat six-dimensional space. The new spatial extra-dimensions will be compactified on a Real Projective Plane. This orbifold is the unique six-dimensional geometry which possesses chiral fermions and a natural Dark Matter candidate. The scalar photon, which is the lightest particle of the first Kaluza-Klein tier, is stabilized by a symmetry relic of the six dimension Lorentz invariance. Using the current constraints from cosmological observations and our first analytical calculation, we derived a characteristic mass range around few hundred GeV for the Kaluza-Klein scalar photon. Therefore the new states of our Universal Extra-Dimension model are light enough to be produced through clear signatures at the Large Hadron Collider. So we used a more sophisticated analysis of particle mass spectrum and couplings, including radiative corrections at one-loop, in order to establish our first predictions and constraints on the expected LHC phenomenology. (author)

  17. Teaching Games for Understanding: A Comprehensive Approach to Promote Student's Motivation in Physical Education.

    Science.gov (United States)

    Hortigüela Alcalá, David; Hernando Garijo, Alejandra

    2017-10-01

    It seems important to consider students' attitudes towards physical education (PE), and the way they learn sports. The present study examines students' perceptions of motivation and achievement in PE after experiencing three consecutive sport units. Two hundred and thirty seven students from the 1st, 2nd, 3rd, and 4th grade in a high school in Burgos (Spain) and two teachers agreed to participate. They were divided into two groups in order to compare two instructional approaches. The experimental group (A), 128 students, experienced Teaching Games for Understanding (TGfU), while the control group (B), 109 students, experienced a technical-traditional approach. Each group was taught by a different teacher. The study followed a mixed-method research design with quantitative (questionnaire) and qualitative (interview) data. Results revealed that group A showed greater motivation and achievement in PE than group B. Significant differences were found in achievement. Participants with better academic results in group A were more positive in sport participation. Meanwhile, students who practiced more extracurricular sports in group B were more actively involved in sport. Teachers disagreed greatly on the way sport should be taught in PE.

  18. Understanding the psychosocial and physical work environment in a Singapore medical school.

    Science.gov (United States)

    Chan, G C T; Koh, D

    2007-02-01

    This study aims to understand the physical and psychosocial work environment, expectations and the perceived levels of stress encountered of medical students in Singapore. A cross-sectional study employing a self-administered work environment questionnaire was applied over a one-week period to the entire 2003/2004 medical school cohort (1,069 students, response rate 85 percent) from the first to fifth (final) years at the National University of Singapore. 3.3 percent had at least one needlestick injury within the academic year. The majority (especially the clinical students) also had musculoskeletal complaints (neck and back mainly) within the last three months. Using the General Health Questionnaire, it was found that 49.6 percent encountered significant stress and 64.6 percent reported that more than 60 percent of their total life stress was due to medical school. The most important psychosocial stressors were: too much work and difficulty in coping. The clinical students were particularly concerned about being good medical students and doctors. The reasons for choosing Medicine as a career and social health (health, study and sleep habits) were also studied. The health risks of a medical student are primarily psychosocial in nature. The biggest challenges are work demands, maintaining a work-life balance and managing the psychosocial work environment.

  19. Understanding science teacher enhancement programs: Essential components and a model

    Science.gov (United States)

    Spiegel, Samuel Albert

    perspectives influence and are examined across three settings, program, individual, and school. An over-arching theme, namely the content focus of the program, such as the teaching and learning of science illuminate both the perspectives and the settings. While the model was developed to understand and evaluate a specific program, it is hypothesized that it can be a powerful tool for designing and implementing a variety of programs.

  20. Understanding bicycling in cities using system dynamics modelling.

    Science.gov (United States)

    Macmillan, Alexandra; Woodcock, James

    2017-12-01

    Increasing urban bicycling has established net benefits for human and environmental health. Questions remain about which policies are needed and in what order, to achieve an increase in cycling while avoiding negative consequences. Novel ways of considering cycling policy are needed, bringing together expertise across policy, community and research to develop a shared understanding of the dynamically complex cycling system. In this paper we use a collaborative learning process to develop a dynamic causal model of urban cycling to develop consensus about the nature and order of policies needed in different cycling contexts to optimise outcomes. We used participatory system dynamics modelling to develop causal loop diagrams (CLDs) of cycling in three contrasting contexts: Auckland, London and Nijmegen. We combined qualitative interviews and workshops to develop the CLDs. We used the three CLDs to compare and contrast influences on cycling at different points on a "cycling trajectory" and drew out policy insights. The three CLDs consisted of feedback loops dynamically influencing cycling, with significant overlap between the three diagrams. Common reinforcing patterns emerged: growing numbers of people cycling lifts political will to improve the environment; cycling safety in numbers drives further growth; and more cycling can lead to normalisation across the population. By contrast, limits to growth varied as cycling increases. In Auckland and London, real and perceived danger was considered the main limit, with added barriers to normalisation in London. Cycling congestion and "market saturation" were important in the Netherlands. A generalisable, dynamic causal theory for urban cycling enables a more ordered set of policy recommendations for different cities on a cycling trajectory. Participation meant the collective knowledge of cycling stakeholders was represented and triangulated with research evidence. Extending this research to further cities, especially in low

  1. Teaching Einsteinian Physics at Schools: Part 2, Models and Analogies for Quantum Physics

    Science.gov (United States)

    Kaur, Tejinder; Blair, David; Moschilla, John; Zadnik, Marjan

    2017-01-01

    The Einstein-First project approaches the teaching of Einsteinian physics through the use of physical models and analogies. This paper presents an approach to the teaching of quantum physics which begins by emphasising the particle-nature of light through the use of toy projectiles to represent photons. This allows key concepts including the…

  2. Engaging Students In Modeling Instruction for Introductory Physics

    Science.gov (United States)

    Brewe, Eric

    2016-05-01

    Teaching introductory physics is arguably one of the most important things that a physics department does. It is the primary way that students from other science disciplines engage with physics and it is the introduction to physics for majors. Modeling instruction is an active learning strategy for introductory physics built on the premise that science proceeds through the iterative process of model construction, development, deployment, and revision. We describe the role that participating in authentic modeling has in learning and then explore how students engage in this process in the classroom. In this presentation, we provide a theoretical background on models and modeling and describe how these theoretical elements are enacted in the introductory university physics classroom. We provide both quantitative and video data to link the development of a conceptual model to the design of the learning environment and to student outcomes. This work is supported in part by DUE #1140706.

  3. Understanding the undelaying mechanism of HA-subtyping in the level of physic-chemical characteristics of protein.

    Directory of Open Access Journals (Sweden)

    Mansour Ebrahimi

    Full Text Available The evolution of the influenza A virus to increase its host range is a major concern worldwide. Molecular mechanisms of increasing host range are largely unknown. Influenza surface proteins play determining roles in reorganization of host-sialic acid receptors and host range. In an attempt to uncover the physic-chemical attributes which govern HA subtyping, we performed a large scale functional analysis of over 7000 sequences of 16 different HA subtypes. Large number (896 of physic-chemical protein characteristics were calculated for each HA sequence. Then, 10 different attribute weighting algorithms were used to find the key characteristics distinguishing HA subtypes. Furthermore, to discover machine leaning models which can predict HA subtypes, various Decision Tree, Support Vector Machine, Naïve Bayes, and Neural Network models were trained on calculated protein characteristics dataset as well as 10 trimmed datasets generated by attribute weighting algorithms. The prediction accuracies of the machine learning methods were evaluated by 10-fold cross validation. The results highlighted the frequency of Gln (selected by 80% of attribute weighting algorithms, percentage/frequency of Tyr, percentage of Cys, and frequencies of Try and Glu (selected by 70% of attribute weighting algorithms as the key features that are associated with HA subtyping. Random Forest tree induction algorithm and RBF kernel function of SVM (scaled by grid search showed high accuracy of 98% in clustering and predicting HA subtypes based on protein attributes. Decision tree models were successful in monitoring the short mutation/reassortment paths by which influenza virus can gain the key protein structure of another HA subtype and increase its host range in a short period of time with less energy consumption. Extracting and mining a large number of amino acid attributes of HA subtypes of influenza A virus through supervised algorithms represent a new avenue for

  4. Understanding the undelaying mechanism of HA-subtyping in the level of physic-chemical characteristics of protein.

    Science.gov (United States)

    Ebrahimi, Mansour; Aghagolzadeh, Parisa; Shamabadi, Narges; Tahmasebi, Ahmad; Alsharifi, Mohammed; Adelson, David L; Hemmatzadeh, Farhid; Ebrahimie, Esmaeil

    2014-01-01

    The evolution of the influenza A virus to increase its host range is a major concern worldwide. Molecular mechanisms of increasing host range are largely unknown. Influenza surface proteins play determining roles in reorganization of host-sialic acid receptors and host range. In an attempt to uncover the physic-chemical attributes which govern HA subtyping, we performed a large scale functional analysis of over 7000 sequences of 16 different HA subtypes. Large number (896) of physic-chemical protein characteristics were calculated for each HA sequence. Then, 10 different attribute weighting algorithms were used to find the key characteristics distinguishing HA subtypes. Furthermore, to discover machine leaning models which can predict HA subtypes, various Decision Tree, Support Vector Machine, Naïve Bayes, and Neural Network models were trained on calculated protein characteristics dataset as well as 10 trimmed datasets generated by attribute weighting algorithms. The prediction accuracies of the machine learning methods were evaluated by 10-fold cross validation. The results highlighted the frequency of Gln (selected by 80% of attribute weighting algorithms), percentage/frequency of Tyr, percentage of Cys, and frequencies of Try and Glu (selected by 70% of attribute weighting algorithms) as the key features that are associated with HA subtyping. Random Forest tree induction algorithm and RBF kernel function of SVM (scaled by grid search) showed high accuracy of 98% in clustering and predicting HA subtypes based on protein attributes. Decision tree models were successful in monitoring the short mutation/reassortment paths by which influenza virus can gain the key protein structure of another HA subtype and increase its host range in a short period of time with less energy consumption. Extracting and mining a large number of amino acid attributes of HA subtypes of influenza A virus through supervised algorithms represent a new avenue for understanding and

  5. Modeling Organizational Design - Applying A Formalism Model From Theoretical Physics

    Directory of Open Access Journals (Sweden)

    Robert Fabac

    2008-06-01

    Full Text Available Modern organizations are exposed to diverse external environment influences. Currently accepted concepts of organizational design take into account structure, its interaction with strategy, processes, people, etc. Organization design and planning aims to align this key organizational design variables. At the higher conceptual level, however, completely satisfactory formulation for this alignment doesn’t exist. We develop an approach originating from the application of concepts of theoretical physics to social systems. Under this approach, the allocation of organizational resources is analyzed in terms of social entropy, social free energy and social temperature. This allows us to formalize the dynamic relationship between organizational design variables. In this paper we relate this model to Galbraith's Star Model and we also suggest improvements in the procedure of the complex analytical method in organizational design.

  6. Searches for Beyond Standard Model Physics with ATLAS and CMS

    CERN Document Server

    Rompotis, Nikolaos; The ATLAS collaboration

    2017-01-01

    The exploration of the high energy frontier with ATLAS and CMS experiments provides one of the best opportunities to look for physics beyond the Standard Model. In this talk, I review the motivation, the strategy and some recent results related to beyond Standard Model physics from these experiments. The review will cover beyond Standard Model Higgs boson searches, supersymmetry and searches for exotic particles.

  7. Structural Acoustic Physics Based Modeling of Curved Composite Shells

    Science.gov (United States)

    2017-09-19

    NUWC-NPT Technical Report 12,236 19 September 2017 Structural Acoustic Physics -Based Modeling of Curved Composite Shells Rachel E. Hesse...SUBTITLE Structural Acoustic Physics -Based Modeling of Curved Composite Shells 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT...study was to use physics -based modeling (PBM) to investigate wave propagations through curved shells that are subjected to acoustic excitation. An

  8. Understanding the complex interplay of barriers to physical activity amongst black and minority ethnic groups in the United Kingdom: a qualitative synthesis using meta-ethnography.

    Science.gov (United States)

    Koshoedo, Sejlo A; Paul-Ebhohimhen, Virginia A; Jepson, Ruth G; Watson, Margaret C

    2015-07-12

    To conduct a meta-ethnographic analysis of qualitative studies to identify barriers to Black and Minority Ethnic (BME) individuals engaging in physical activity in the UK context. A qualitative synthesis using meta-ethnographic methods to synthesis studies of barriers to engaging in physical activity among BME groups in the UK. A comprehensive search strategy of multiple databases was employed to identify qualitative research studies published up to October 2012. The eleven searched databases included ASSIA, MEDLINE, EMBASE, CINAHL, Health Technology Assessment (HTA), NHS Scotland Library, Physical Activity Health Alliance (PAHA), PsyINFO, Social Services Abstract, Sport discuss and Web of Science. The Noblit and Hare's meta-ethnographic approach was undertaken to develop an inductive and interpretive form of knowledge synthesis. Fourteen papers met the inclusion criteria. The synthesis indicated that barriers to physical activity among BME individuals were influenced by four main concepts: perceptions; cultural expectations; personal barriers; and factors limiting access to facilities. BME individuals had different understandings of physical activity were influenced by migration history, experiences, cultural and health beliefs. This in turn may have a disempowering effect on BME individuals in terms of adopting or maintaining physical activity. These barriers to physical activity were explained at a higher conceptual level by a socio-ecological model. The social construct 'individual perception and understanding of physical activity' was particularly relevant to theoretical models and interventions. Interventions to promote engagement with physical activity need to address perceptions of this behaviour. The elicited concepts and contexts could be used to enhance the development of tailored effective health promotion interventions for BME individuals.

  9. Assessing Models of Public Understanding In ELSI Outreach Materials

    Energy Technology Data Exchange (ETDEWEB)

    Bruce V. Lewenstein, Ph.D.; Dominique Brossard, Ph.D.

    2006-03-01

    Advances in the science of genetics have implications for individuals and society, and have to be taken into account at the policy level. Studies of ethical, legal and social issues related to genomic research have therefore been integrated in the Human Genome Project (HGP) since the earliest days of the project. Since 1990, three to five percent of the HGP annual budget has been devoted to such studies, under the umbrella of the Ethical, Legal, and Social Implications (ELSI) Programs of the National Human Genome Research Institute of the National Institute of Health, and of the Office of Biological and Environmental Research of the U.S. Department of Energy (DOE). The DOE-ELSI budget has been used to fund a variety of projects that have aimed at ?promoting education and help guide the conduct of genetic research and the development of related medical and public policies? (HGP, 2003). As part of the educational component, a significant portion of DOE-ELSI funds have been dedicated to public outreach projects, with the underlying goal of promoting public awareness and ultimately public discussion of ethical, legal, and social issues surrounding availability of genetic information (Drell, 2002). The essential assumption behind these projects is that greater access to information will lead to more knowledge about ethical, legal and social issues, which in turn will lead to enhanced ability on the part of individuals and communities to deal with these issues when they encounter them. Over the same period of time, new concepts of ?public understanding of science? have emerged in the theoretical realm, moving from a ?deficit? or linear dissemination of popularization, to models stressing lay-knowledge, public engagement and public participation in science policy-making (Lewenstein, 2003). The present project uses the base of DOE-funded ELSI educational project to explore the ways that information about a new and emerging area of science that is intertwined with public

  10. Physical Model-Based Investigation of Reservoir Sedimentation Processes

    Directory of Open Access Journals (Sweden)

    Cheng-Chia Huang

    2018-03-01

    Full Text Available Sedimentation is a serious problem in the operations of reservoirs. In Taiwan, the situation became worse after the Chi-Chi Earthquake recorded on 21 September 1999. The sediment trap efficiency in several regional reservoirs has been sharply increased, adversely affecting the operations on water supplies. According to the field record, the average annual sediment deposition observed in several regional reservoirs in Taiwan has been increased. For instance, the typhoon event recorded in 2008 at the Wushe Reservoir, Taiwan, produced a 3 m sediment deposit upstream of the dam. The remaining storage capacity in the Wushe Reservoir was reduced to 35.9% or a volume of 53.79 million m3 for flood water detention in 2010. It is urgent that research should be conducted to understand the sediment movement in the Wushe Reservoir. In this study, a scale physical model was built to reproduce the flood flow through the reservoir, investigate the long-term depositional pattern, and evaluate sediment trap efficiency. This allows us to estimate the residual life of the reservoir by proposing a modification of Brune’s method. It can be presented to predict the lifespan of Taiwan reservoirs due to higher applicability in both the physical model and the observed data.

  11. Mathematical Model of the Public Understanding of Space Science

    Science.gov (United States)

    Prisniakov, V.; Prisniakova, L.

    The success in deployment of the space programs now in many respects depends on comprehension by the citizens of necessity of programs, from "space" erudition of country. Purposefulness and efficiency of the "space" teaching and educational activity depend on knowledge of relationships between separate variables of such process. The empirical methods of ``space'' well-information of the taxpayers should be supplemented by theoretical models permitting to demonstrate a ways of control by these processes. Authors on the basis of their experience of educational activity during 50- years of among the students of space-rocket profession obtain an equation of ``space" state of the society determining a degree of its knowledge about Space, about achievements in its development, about indispensable lines of investigations, rates of informatization of the population. It is supposed, that the change of the space information consists of two parts: (1) - from going of the information about practical achievements, about development special knowledge requiring of independent financing, and (2) from intensity of dissemination of the ``free" information of a general educational line going to the population through mass-media, book, in family, in educational institutions, as a part of obligatory knowledge of any man, etc. In proposed model the level space well-information of the population depends on intensity of dissemination in the society of the space information, and also from a volume of financing of space-rocket technology, from a part of population of the employment in the space-rocket programs, from a factor of education of the population in adherence to space problems, from welfare and mentality of the people, from a rate of unemployment and material inequality. Obtained in the report on these principles the equation of a space state of the society corresponds to catastrophe such as cusp, the analysis has shown which one ways of control of the public understanding of space

  12. Physics-Based Pneumatic Hammer Instability Model, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Florida Turbine Technologies (FTT) proposes to conduct research necessary to develop a physics-based pneumatic hammer instability model for hydrostatic bearings...

  13. Flavor physics and right-handed models

    Energy Technology Data Exchange (ETDEWEB)

    Shafaq, Saba

    2010-08-20

    The Standard Model of particle physics only provides a parametrization of flavor which involves the values of the quark and lepton masses and unitary flavor mixing matrix i.e. CKM (Cabibbo-Kobayashi-Masakawa) matrix for quarks. The precise determination of elements of the CKM matrix is important for the study of the flavor sector of quarks. Here we concentrate on the matrix element vertical stroke V{sub cb} vertical stroke. In particular we consider the effects on the value of vertical stroke V{sub cb} vertical stroke from possible right-handed admixtures along with the usually left-handed weak currents. Left Right Symmetric Model provide a natural basis for right-handed current contributions and has been studied extensively in the literature but has never been discussed including flavor. In the first part of the present work an additional flavor symmetry is included in LRSM which allows a systematic study of flavor effects. The second part deals with the practical extraction of a possible right-handed contribution. Starting from the quark level transition b{yields}c we use heavy quark symmetries to relate the helicities of the quarks to experimentally accessible quantities. To this end we study the decays anti B{yields}D(D{sup *})l anti {nu} which have been extensively explored close to non recoil point. By taking into account SCET (Soft Collinear Effective Theory) formalism it has been extended to a maximum recoil point i.e. {upsilon} . {upsilon}{sup '} >>1. We derive a factorization formula, where the set of form factors is reduced to a single universal form factor {xi}({upsilon} . {upsilon}{sup '}) up to hard-scattering corrections. Symmetry relations on form factors for exclusive anti B {yields} D(D{sup *})l anti {nu} transition has been derived in terms of {xi}({upsilon} . {upsilon}{sup '}). These symmetries are then broken by perturbative effects. The perturbative corrections to symmetry-breaking corrections to first order in the strong

  14. What is This Thing Called Sensemaking?: A Theoretical Framework for How Physics Students Resolve Inconsistencies in Understanding

    Science.gov (United States)

    Odden, Tor Ole B.

    Students often emerge from introductory physics courses with a feeling that the concepts they have learned do not make sense. In recent years, science education researchers have begun to attend to this type of problem by studying the ways in which students make sense of science concepts. However, although many researchers agree intuitively on what sensemaking looks like, the literature on sensemaking is both theoretically fragmented and provides few guidelines for how to encourage and support the process. In this dissertation, I address this challenge by proposing a theoretical framework to describe students' sensemaking processes. I base this framework both on the science education research literature on sensemaking and on a series of video-recorded cognitive, clinical interviews conducted with introductory physics students enrolled in a course on electricity and magnetism. Using the science education research literature on sensemaking as well as a cognitivist, dynamic network model of mind as a theoretical lens, I first propose a coherent definition of sensemaking. Then, using this definition I analyze the sensemaking processes of these introductory physics students during episodes when they work to articulate and resolve gaps or inconsistencies in their understanding. Based on the students' framing, gestures, and dialogue I argue that the process of sensemaking unfolds in a distinct way, which we can describe as an epistemic game in which students first build a framework of knowledge, then identify a gap or inconsistency in that framework, iteratively build an explanation to resolve the gap or inconsistency, and (sometimes) successfully resolve it. I further argue that their entry into the sensemaking frame is facilitated by a specific question, which is in turn motivated by a gap or inconsistency in knowledge that I call the vexation point. I also investigate the results of sensemaking, arguing that students may use the technique of conceptual blending to both

  15. Understanding quantum measurement from the solution of dynamical models

    Energy Technology Data Exchange (ETDEWEB)

    Allahverdyan, Armen E. [Laboratoire de Physique Statistique et Systèmes Complexes, ISMANS, 44 Av. Bartholdi, 72000 Le Mans (France); Balian, Roger [Institut de Physique Théorique, CEA Saclay, 91191 Gif-sur-Yvette cedex (France); Nieuwenhuizen, Theo M., E-mail: T.M.Nieuwenhuizen@uva.nl [Center for Cosmology and Particle Physics, New York University, 4 Washington Place, New York, NY 10003 (United States)

    2013-04-15

    The quantum measurement problem, to wit, understanding why a unique outcome is obtained in each individual experiment, is currently tackled by solving models. After an introduction we review the many dynamical models proposed over the years for elucidating quantum measurements. The approaches range from standard quantum theory, relying for instance on quantum statistical mechanics or on decoherence, to quantum–classical methods, to consistent histories and to modifications of the theory. Next, a flexible and rather realistic quantum model is introduced, describing the measurement of the z-component of a spin through interaction with a magnetic memory simulated by a Curie–Weiss magnet, including N≫1 spins weakly coupled to a phonon bath. Initially prepared in a metastable paramagnetic state, it may transit to its up or down ferromagnetic state, triggered by its coupling with the tested spin, so that its magnetization acts as a pointer. A detailed solution of the dynamical equations is worked out, exhibiting several time scales. Conditions on the parameters of the model are found, which ensure that the process satisfies all the features of ideal measurements. Various imperfections of the measurement are discussed, as well as attempts of incompatible measurements. The first steps consist in the solution of the Hamiltonian dynamics for the spin-apparatus density matrix D{sup -hat} (t). Its off-diagonal blocks in a basis selected by the spin–pointer coupling, rapidly decay owing to the many degrees of freedom of the pointer. Recurrences are ruled out either by some randomness of that coupling, or by the interaction with the bath. On a longer time scale, the trend towards equilibrium of the magnet produces a final state D{sup -hat} (t{sub f}) that involves correlations between the system and the indications of the pointer, thus ensuring registration. Although D{sup -hat} (t{sub f}) has the form expected for ideal measurements, it only describes a large set of

  16. "Quod Erat Demonstrandum": Understanding and Explaining Equations in Physics Teacher Education

    Science.gov (United States)

    Karam, Ricardo; Krey, Olaf

    2015-01-01

    In physics education, equations are commonly seen as calculation tools to solve problems or as concise descriptions of experimental regularities. In physical science, however, equations often play a much more important role associated with the formulation of theories to provide explanations for physical phenomena. In order to overcome this…

  17. Applying Self-Determination Theory to Understand the Motivation for Becoming a Physical Education Teacher

    Science.gov (United States)

    Spittle, Michael; Jackson, Kevin; Casey, Meghan

    2009-01-01

    This study explored the reasons people choose physical education teaching as a profession and investigated the relationship of these choices with motivation. Physical education pre-service teachers (n = 324) completed the Academic Motivation Scale (AMS) and a measure of reasons for choosing physical education teaching. Confident interpersonal…

  18. Understanding Factors Associated with Children's Motivation to Engage in Recess-Time Physical Activity

    Science.gov (United States)

    Efrat, Merav W.

    2016-01-01

    Physical activity is linked with health and academic benefits. While recess provides the greatest opportunity for children to accumulate physical activity, most children are not motivated to engage in sufficient amounts of physical activity during recess. Research demonstrates a strong relationship between self-efficacy and children's motivation…

  19. Hands-On Experiments in the Interactive Physics Laboratory: Students' Intrinsic Motivation and Understanding

    Science.gov (United States)

    Snetinová, Marie; Kácovský, Petr; Machalická, Jana

    2018-01-01

    Experiments in different forms can certainly be suitable tools for increasing student interest in physics. However, educators continuously discuss which forms of experimenting (if any) are the most beneficial for these purposes. At the Faculty of Mathematics and Physics, Charles University, Prague, two different forms of physics experiments are…

  20. Standard Model Physics at the LHC

    CERN Document Server

    CERN. Geneva

    1999-01-01

    1. Top Physics : Single top production and top polarization, D. O'Neil. Top mass determination, spin correlations and t-tbar asymmetries, L. Sonnenschein. FCNC-induced production and decays, S. Slabospitsky. MC tools for signals and backgrounds, M. Mangano. Plans for the writing of the final report, Conveners. Top physics: Discussion. 2. Electroweak physics (cont.) : Anomalous triple gauge boson couplings: analysis, strategies, and form factor considerations, M. Dobbs. Sensitivity to anomalous triple gauge boson couplings, W. Thuemmel. Drell-Yan production of W,Z with electroweak corrections, S. Dittmaier. Vector boson self-couplings and effective field theory, J.R. Pelaez. Recent theoretical progress, Z. Kunszt. Electroweak physics: Discussion. Recent theoretical progress in b production, G. Ridolf. Studies on b production, S. Gennai. Comparison of most recent b-production theoretical computations with PYTHIA, A. Kharchilava. Possibilities for b production measurements, P. Vikas. B production: Discussion....

  1. B physics in the standard model

    International Nuclear Information System (INIS)

    Takasugi, Eiichi

    1985-01-01

    Before discussing the beauty physics, the present status of the quark mixing is reviewed. Then the CP violation in the K meson physics is discussed. As for the quark mixing, it is concluded that the theroretical analysis of CP violation involves various uncertainties and it seems difficult to obtain the definite information of the quark mixing. As for the B physics, B 0 - anti B 0 mixing and some hopeful methods to detect the CP violation in the B system are discussed along with the two typical ways to measure it. In summary, it is concluded that the B 0 - anti B 0 mixing should be observed, but some luck is needed to observe the CP violation in the B physics. (Aoki, K.)

  2. Understanding arsenic carcinogenicity by the use of animal models

    International Nuclear Information System (INIS)

    Wanibuchi, Hideki; Salim, Elsayed I.; Kinoshita, Anna; Shen Jun; Wei Min; Morimura, Keiichirou; Yoshida, Kaoru; Kuroda, Koichi; Endo, Ginji; Fukushima, Shoji

    2004-01-01

    Although numerous epidemiological studies have indicated that human arsenic exposure is associated with increased incidences of bladder, liver, skin, and lung cancers, limited attempts have been made to understand mechanisms of carcinogenicity using animal models. Dimethylarsinic acid (DMA), an organic arsenic compound, is a major metabolite of ingested inorganic arsenics in mammals. Recent in vitro studies have proven DMA to be a potent clastogenic agent, capable of inducing DNA damage including double strand breaks and cross-link formation. In our attempts to clarify DMA carcinogenicity, we have recently shown carcinogenic effects of DMA and its related metabolites using various experimental protocols in rats and mice: (1) a multi-organ promotion bioassay in rats; (2) a two-stage promotion bioassay by DMA of rat urinary bladder and liver carcinogenesis; (3) a 2-year carcinogenicity test of DMA in rats; (4) studies on the effects of DMA on lung carcinogenesis in rats; (5) promotion of skin carcinogenesis by DMA in keratin (K6)/ornithine decarboxylase (ODC) transgenic mice; (6) carcinogenicity of DMA in p53(+/-) knockout and Mmh/8-OXOG-DNA glycolase (OGG1) mutant mice; (7) promoting effects of DMA and related organic arsenicals in rat liver; (8) promoting effects of DMA and related organic arsenicals in a rat multi-organ carcinogenesis test; and (9) 2-year carcinogenicity tests of monomethylarsonic acid (MMA) and trimethylarsine oxide (TMAO) in rats. The results revealed that the adverse effects of arsenic occurred either by promoting and initiating carcinogenesis. These data, as covered in the present review, suggest that several mechanisms may be involved in arsenic carcinogenesis

  3. A meta-analytic review of Elliot's (1999 Hierarchical Model of Approach and Avoidance Motivation in the sport, physical activity, and physical education literature

    Directory of Open Access Journals (Sweden)

    Marc Lochbaum

    2017-03-01

    Conclusion: Future research is encouraged to grow and enrich the understanding of achievement goals within Elliot's complete Hierarchical Model of Approach and Avoidance Motivation to include both antecedents and outcomes simultaneously to improve upon the understanding of achievement motivation in sport, exercise, and physical activity settings.

  4. Investigating conceptual models for physical property couplings in solid solution models of cement

    International Nuclear Information System (INIS)

    Benbow, Steven; Watson, Claire; Savage, David

    2005-11-01

    The long-term behaviour of cementitious engineered barriers is an important process to consider when modelling the migration of radionuclides from a geological repository for nuclear waste. The modelling of cement is complicated by the fact that the cement is dominated by the behaviour of calcium silicate hydrate (CSH) gel which is a complex solid exhibiting incongruent dissolution behaviour. In this report, we have demonstrated the implementation of a solid-solution CSH gel model within a geochemical transport modelling framework using the Raiden computer code to investigate cement/concrete-groundwater interactions. The modelling conducted here shows that it is possible to couple various conceptual models for the evolution of physical properties of concrete with a solid solution model for cement degradation in a fully coupled geochemical transport model to describe the interaction of cement/concrete engineered barriers with groundwater. The results show that changes to the conceptual models and flow rates can give rise to very different evolutions. Most simulations were carried out at a reduced 'experimental' scale rather than full repository scale. The work has shown the possibility to investigate also the changing physical properties of degrading cement. To further develop the model more emphasis is needed on kinetics and the detailed development of a nearly clogged pore space. Modelling of the full repository scale could be another way forward to understand the behaviour of degrading concrete. A general conclusion is that the combined effects of chemical evolution and physical degradation should be analysed in performance assessments of cementitious repositories. Moreover, the project results will be used as one basis in coming reviews of SKB's safety assessments of repositories for spent fuel and low-and intermediate level waste

  5. Investigating conceptual models for physical property couplings in solid solution models of cement

    Energy Technology Data Exchange (ETDEWEB)

    Benbow, Steven; Watson, Claire; Savage, David [Quintesssa Ltd., Henley-on-Thames (United Kingdom)

    2005-11-15

    The long-term behaviour of cementitious engineered barriers is an important process to consider when modelling the migration of radionuclides from a geological repository for nuclear waste. The modelling of cement is complicated by the fact that the cement is dominated by the behaviour of calcium silicate hydrate (CSH) gel which is a complex solid exhibiting incongruent dissolution behaviour. In this report, we have demonstrated the implementation of a solid-solution CSH gel model within a geochemical transport modelling framework using the Raiden computer code to investigate cement/concrete-groundwater interactions. The modelling conducted here shows that it is possible to couple various conceptual models for the evolution of physical properties of concrete with a solid solution model for cement degradation in a fully coupled geochemical transport model to describe the interaction of cement/concrete engineered barriers with groundwater. The results show that changes to the conceptual models and flow rates can give rise to very different evolutions. Most simulations were carried out at a reduced 'experimental' scale rather than full repository scale. The work has shown the possibility to investigate also the changing physical properties of degrading cement. To further develop the model more emphasis is needed on kinetics and the detailed development of a nearly clogged pore space. Modelling of the full repository scale could be another way forward to understand the behaviour of degrading concrete. A general conclusion is that the combined effects of chemical evolution and physical degradation should be analysed in performance assessments of cementitious repositories. Moreover, the project results will be used as one basis in coming reviews of SKB's safety assessments of repositories for spent fuel and low-and intermediate level waste.

  6. Understanding the Importance of Context: A Qualitative Study of a Location-Based Exergame to Enhance School Childrens Physical Activity.

    Directory of Open Access Journals (Sweden)

    Judy Robertson

    Full Text Available Many public health interventions are less effective than expected in 'real life settings', yet little work is undertaken to understand the reasons why. The effectiveness of complex public health interventions can often be traced back to a robust programme theory (how and why an intervention brings about a change in outcome(s and assumptions that are made about the context in which it is implemented. Understanding whether effectiveness (or lack thereof is due to the intervention or the context is hugely helpful in decisions about whether to a modify the intervention; b modify the context; c stop providing the intervention. Exergames-also known as Active Video Games or AVGS-are video games which use the player's bodily movements as input and have potential to increase physical activity in children. However, the results of a recent pilot randomised controlled trial (RCT of a location-based exergame (FitQuest in a school setting were inconclusive; no significant effect was detected for any of the outcome measures. The aim of this study was to explore whether the programme theory for FitQuest was correct with respect to how and why it would change children's perceptions of physical activity (PA and exercise self-efficacy in the school setting. A further aim was to investigate the features of the school setting (context that may impact on FitQuest's implementation and effectiveness. Qualitative data (gathered during the RCT were gathered from interviews with teachers and children, and observation of sessions using FitQuest. Thematic analysis indicated that whilst children enjoyed playing the game, engaged with goal setting within the game context and undertook low to vigorous physical activity, there were significant contextual factors that prevented it from being played as often as intended. These included environmental factors (e.g. size of the playground, school factors (cancellations due to other activities, school technology policy (rules

  7. Understanding the Importance of Context: A Qualitative Study of a Location-Based Exergame to Enhance School Childrens Physical Activity.

    Science.gov (United States)

    Robertson, Judy; Jepson, Ruth; Macvean, Andrew; Gray, Stuart

    2016-01-01

    Many public health interventions are less effective than expected in 'real life settings', yet little work is undertaken to understand the reasons why. The effectiveness of complex public health interventions can often be traced back to a robust programme theory (how and why an intervention brings about a change in outcome(s)) and assumptions that are made about the context in which it is implemented. Understanding whether effectiveness (or lack thereof) is due to the intervention or the context is hugely helpful in decisions about whether to a) modify the intervention; b) modify the context; c) stop providing the intervention. Exergames-also known as Active Video Games or AVGS-are video games which use the player's bodily movements as input and have potential to increase physical activity in children. However, the results of a recent pilot randomised controlled trial (RCT) of a location-based exergame (FitQuest) in a school setting were inconclusive; no significant effect was detected for any of the outcome measures. The aim of this study was to explore whether the programme theory for FitQuest was correct with respect to how and why it would change children's perceptions of physical activity (PA) and exercise self-efficacy in the school setting. A further aim was to investigate the features of the school setting (context) that may impact on FitQuest's implementation and effectiveness. Qualitative data (gathered during the RCT) were gathered from interviews with teachers and children, and observation of sessions using FitQuest. Thematic analysis indicated that whilst children enjoyed playing the game, engaged with goal setting within the game context and undertook low to vigorous physical activity, there were significant contextual factors that prevented it from being played as often as intended. These included environmental factors (e.g. size of the playground), school factors (cancellations due to other activities), school technology policy (rules relating to

  8. Physical understanding of the instability spectrum and the feedback control of resistive wall modes in reversed field pinch

    International Nuclear Information System (INIS)

    Wang, Z.R.; Guo, S.C.

    2011-01-01

    The cylindrical MHD model integrated with a feedback system is applied to the study of resistive wall mode (RWM) in reversed field pinch (RFP) plasmas. The model takes into account the compressibility, longitudinal flow, viscosity and resistive wall with a finite thickness. The study, via both analytical and numerical analyses, provides a physical understanding on the following subjects: firstly, on the nature of the instability spectrum of the RWM observed in RFP plasmas; specifically, the growth rates of the two groups of the RWMs (internally non-resonant and externally non-resonant) have opposite dependence on the variation of the field reversal. Secondly, on the response of the unstable plasmas to the feedback control in RFPs, the mode behaviour in plasmas under the feedback is clarified and discussed in detail. Finally, the linear solutions of time evolution of RWM instability in various feedback scenarios are given. The effects of the wall proximity, the sensor location and the system response time are discussed, respectively.

  9. Understanding soft condensed matter via modeling and computation

    CERN Document Server

    Shi, An-Chang

    2011-01-01

    All living organisms consist of soft matter. For this reason alone, it is important to be able to understand and predict the structural and dynamical properties of soft materials such as polymers, surfactants, colloids, granular matter and liquids crystals. To achieve a better understanding of soft matter, three different approaches have to be integrated: experiment, theory and simulation. This book focuses on the third approach - but always in the context of the other two.

  10. Millimeter-wave imaging of magnetic fusion plasmas: technology innovations advancing physics understanding

    Science.gov (United States)

    Wang, Y.; Tobias, B.; Chang, Y.-T.; Yu, J.-H.; Li, M.; Hu, F.; Chen, M.; Mamidanna, M.; Phan, T.; Pham, A.-V.; Gu, J.; Liu, X.; Zhu, Y.; Domier, C. W.; Shi, L.; Valeo, E.; Kramer, G. J.; Kuwahara, D.; Nagayama, Y.; Mase, A.; Luhmann, N. C., Jr.

    2017-07-01

    Electron cyclotron emission (ECE) imaging is a passive radiometric technique that measures electron temperature fluctuations; and microwave imaging reflectometry (MIR) is an active radar imaging technique that measures electron density fluctuations. Microwave imaging diagnostic instruments employing these techniques have made important contributions to fusion science and have been adopted at major fusion facilities worldwide including DIII-D, EAST, ASDEX Upgrade, HL-2A, KSTAR, LHD, and J-TEXT. In this paper, we describe the development status of three major technological advancements: custom mm-wave integrated circuits (ICs), digital beamforming (DBF), and synthetic diagnostic modeling (SDM). These have the potential to greatly advance microwave fusion plasma imaging, enabling compact and low-noise transceiver systems with real-time, fast tracking ability to address critical fusion physics issues, including ELM suppression and disruptions in the ITER baseline scenario, naturally ELM-free states such as QH-mode, and energetic particle confinement (i.e. Alfvén eigenmode stability) in high-performance regimes that include steady-state and advanced tokamak scenarios. Furthermore, these systems are fully compatible with today’s most challenging non-inductive heating and current drive systems and capable of operating in harsh environments, making them the ideal approach for diagnosing long-pulse and steady-state tokamaks.

  11. Understanding the Flow Physics of Shock Boundary-Layer Interactions Using CFD and Numerical Analyses

    Science.gov (United States)

    Friedlander, David J.

    2013-01-01

    Computational fluid dynamic (CFD) analyses of the University of Michigan (UM) Shock/Boundary-Layer Interaction (SBLI) experiments were performed as an extension of the CFD SBLI Workshop held at the 48th AIAA Aerospace Sciences Meeting in 2010. In particular, the UM Mach 2.75 Glass Tunnel with a semi-spanning 7.75deg wedge was analyzed in attempts to explore key physics pertinent to SBLI's, including thermodynamic and viscous boundary conditions as well as turbulence modeling. Most of the analyses were 3D CFD simulations using the OVERFLOW flow solver, with additional quasi-1D simulations performed with an in house MATLAB code interfacing with the NIST REFPROP code to explore perfect verses non-ideal air. A fundamental exploration pertaining to the effects of particle image velocimetry (PIV) on post-processing data is also shown. Results from the CFD simulations showed an improvement in agreement with experimental data with key contributions including adding a laminar zone upstream of the wedge and the necessity of mimicking PIV particle lag for comparisons. Results from the quasi-1D simulation showed that there was little difference between perfect and non-ideal air for the configuration presented.

  12. PWR surveillance based on correspondence between empirical models and physical

    International Nuclear Information System (INIS)

    Zwingelstein, G.; Upadhyaya, B.R.; Kerlin, T.W.

    1976-01-01

    An on line surveillance method based on the correspondence between empirical models and physicals models is proposed for pressurized water reactors. Two types of empirical models are considered as well as the mathematical models defining the correspondence between the physical and empirical parameters. The efficiency of this method is illustrated for the surveillance of the Doppler coefficient for Oconee I (an 886 MWe PWR) [fr

  13. Physical Modelling of Geotechnical Structures in Ports and Offshore

    Directory of Open Access Journals (Sweden)

    Bałachowski Lech

    2017-04-01

    Full Text Available The physical modelling of subsoil behaviour and soil-structure interaction is essential for the proper design of offshore structures and port infrastructure. A brief introduction to such modelling of geoengineering problems is presented and some methods and experimental devices are described. The relationships between modelling scales are given. Some examples of penetration testing results in centrifuge and calibration chamber are presented. Prospects for physical modelling in geotechnics are also described.

  14. Beans (Phaseolus ssp.) as a Model for Understanding Crop Evolution

    Science.gov (United States)

    Bitocchi, Elena; Rau, Domenico; Bellucci, Elisa; Rodriguez, Monica; Murgia, Maria L.; Gioia, Tania; Santo, Debora; Nanni, Laura; Attene, Giovanna; Papa, Roberto

    2017-01-01

    Here, we aim to provide a comprehensive and up-to-date overview of the most significant outcomes in the literature regarding the origin of Phaseolus genus, the geographical distribution of the wild species, the domestication process, and the wide spread out of the centers of origin. Phaseolus can be considered as a unique model for the study of crop evolution, and in particular, for an understanding of the convergent phenotypic evolution that occurred under domestication. The almost unique situation that characterizes the Phaseolus genus is that five of its ∼70 species have been domesticated (i.e., Phaseolus vulgaris, P. coccineus, P. dumosus, P. acutifolius, and P. lunatus), and in addition, for P. vulgaris and P. lunatus, the wild forms are distributed in both Mesoamerica and South America, where at least two independent and isolated episodes of domestication occurred. Thus, at least seven independent domestication events occurred, which provides the possibility to unravel the genetic basis of the domestication process not only among species of the same genus, but also between gene pools within the same species. Along with this, other interesting features makes Phaseolus crops very useful in the study of evolution, including: (i) their recent divergence, and the high level of collinearity and synteny among their genomes; (ii) their different breeding systems and life history traits, from annual and autogamous, to perennial and allogamous; and (iii) their adaptation to different environments, not only in their centers of origin, but also out of the Americas, following their introduction and wide spread through different countries. In particular for P. vulgaris this resulted in the breaking of the spatial isolation of the Mesoamerican and Andean gene pools, which allowed spontaneous hybridization, thus increasing of the possibility of novel genotypes and phenotypes. This knowledge that is associated to the genetic resources that have been conserved ex situ and in

  15. Understanding and modelling Neo-proterozoic glaciations and their associated phenomena

    International Nuclear Information System (INIS)

    Le Hir, Guillaume

    2007-01-01

    The objective of this research thesis is to provide a consistent image of extreme glaciations which occurred during the Neo-proterozoic era. By using climate and carbon cycle models (or model of bio-geochemical cycles), the author aims at answering various scientific questions raised by the Snowball Earth hypothesis. After a description of the main geological features which characterize the Proterozoic, scientific problems are presented. The author then reports the study of carbon cycle during glaciation in order to understand its operation. Based on this constraint, a consistent scenario of exit from glaciation is defined. The physical-chemical evolution of the ocean during and after a global glaciation is then quantified in order to assess its potential effects on the environment and on the Precambrian biosphere. The last part focuses on the post-glacial evolution to establish the delay for a return to equilibrium of climate after such an extreme event [fr

  16. Slush Fund: Modeling the Multiphase Physics of Oceanic Ices

    Science.gov (United States)

    Buffo, J.; Schmidt, B. E.

    2016-12-01

    The prevalence of ice interacting with an ocean, both on Earth and throughout the solar system, and its crucial role as the mediator of exchange between the hydrosphere below and atmosphere above, have made quantifying the thermodynamic, chemical, and physical properties of the ice highly desirable. While direct observations of these quantities exist, their scarcity increases with the difficulty of obtainment; the basal surfaces of terrestrial ice shelves remain largely unexplored and the icy interiors of moons like Europa and Enceladus have never been directly observed. Our understanding of these entities thus relies on numerical simulation, and the efficacy of their incorporation into larger systems models is dependent on the accuracy of these initial simulations. One characteristic of seawater, likely shared by the oceans of icy moons, is that it is a solution. As such, when it is frozen a majority of the solute is rejected from the forming ice, concentrating in interstitial pockets and channels, producing a two-component reactive porous media known as a mushy layer. The multiphase nature of this layer affects the evolution and dynamics of the overlying ice mass. Additionally ice can form in the water column and accrete onto the basal surface of these ice masses via buoyancy driven sedimentation as frazil or platelet ice. Numerical models hoping to accurately represent ice-ocean interactions should include the multiphase behavior of these two phenomena. While models of sea ice have begun to incorporate multiphase physics into their capabilities, no models of ice shelves/shells explicitly account for the two-phase behavior of the ice-ocean interface. Here we present a 1D multiphase model of floating oceanic ice that includes parameterizations of both density driven advection within the `mushy layer' and buoyancy driven sedimentation. The model is validated against contemporary sea ice models and observational data. Environmental stresses such as supercooling and

  17. Understanding the Nature of Measurement Error When Estimating Energy Expenditure and Physical Activity via Physical Activity Recall.

    Science.gov (United States)

    Paul, David R; McGrath, Ryan; Vella, Chantal A; Kramer, Matthew; Baer, David J; Moshfegh, Alanna J

    2018-03-26

    The National Health and Nutrition Examination Survey physical activity questionnaire (PAQ) is used to estimate activity energy expenditure (AEE) and moderate to vigorous physical activity (MVPA). Bias and variance in estimates of AEE and MVPA from the PAQ have not been described, nor the impact of measurement error when utilizing the PAQ to predict biomarkers and categorize individuals. The PAQ was administered to 385 adults to estimate AEE (AEE:PAQ) and MVPA (MVPA:PAQ), while simultaneously measuring AEE with doubly labeled water (DLW; AEE:DLW) and MVPA with an accelerometer (MVPA:A). Although AEE:PAQ [3.4 (2.2) MJ·d -1 ] was not significantly different from AEE:DLW [3.6 (1.6) MJ·d -1 ; P > .14], MVPA:PAQ [36.2 (24.4) min·d -1 ] was significantly higher than MVPA:A [8.0 (10.4) min·d -1 ; P PAQ regressed on AEE:DLW and MVPA:PAQ regressed on MVPA:A yielded not only significant positive relationships but also large residual variances. The relationships between AEE and MVPA, and 10 of the 12 biomarkers were underestimated by the PAQ. When compared with accelerometers, the PAQ overestimated the number of participants who met the Physical Activity Guidelines for Americans. Group-level bias in AEE:PAQ was small, but large for MVPA:PAQ. Poor within-participant estimates of AEE:PAQ and MVPA:PAQ lead to attenuated relationships with biomarkers and misclassifications of participants who met or who did not meet the Physical Activity Guidelines for Americans.

  18. Patients' mental models and adherence to outpatient physical therapy home exercise programs.

    Science.gov (United States)

    Rizzo, Jon

    2015-05-01

    Within physical therapy, patient adherence usually relates to attending appointments, following advice, and/or undertaking prescribed exercise. Similar to findings for general medical adherence, patient adherence to physical therapy home exercise programs (HEP) is estimated between 35 and 72%. Adherence to HEPs is a multifactorial and poorly understood phenomenon, with no consensus regarding a common theoretical framework that best guides empirical or clinical efforts. Mental models, a construct used to explain behavior and decision-making in the social sciences, may serve as this framework. Mental models comprise an individual's tacit thoughts about how the world works. They include assumptions about new experiences and expectations for the future based on implicit comparisons between current and past experiences. Mental models play an important role in decision-making and guiding actions. This professional theoretical article discusses empirical research demonstrating relationships among mental models, prior experience, and adherence decisions in medical and physical therapy contexts. Specific issues related to mental models and physical therapy patient adherence are discussed, including the importance of articulation of patients' mental models, assessment of patients' mental models that relate to exercise program adherence, discrepancy between patient and provider mental models, and revision of patients' mental models in ways that enhance adherence. The article concludes with practical implications for physical therapists and recommendations for further research to better understand the role of mental models in physical therapy patient adherence behavior.

  19. Concepts and models in particle physics

    International Nuclear Information System (INIS)

    Paty, M.

    1977-01-01

    The knowledge of Elementary Particle Physics is characterized by an object and a purpose which are both highly theoretical. This assessment is shown and analysed by some examples taken in recent achievements in the field. It is also tried to attempt an enonciation of some criteria of the reality for concepts and objects in this matter [fr

  20. Extracting physics from the lattice higgs model

    International Nuclear Information System (INIS)

    Neuberger, H.

    1988-05-01

    The relevance and usefulness of lattice /phi/ 4 for particle physics is discussed from older and newer points of view. The talk will start with a review of the main ideas and suggestions in my work in the past with Dashen and will proceed to present newer developments both on the conceptual and the practical level. 12 refs

  1. An Amotivation Model in Physical Education

    Science.gov (United States)

    Shen, Bo; Wingert, Robert K.; Li, Weidong; Sun, Haichun; Rukavina, Paul Bernard

    2010-01-01

    Amotivation refers to a state in which individuals cannot perceive a relationship between their behavior and that behavior's subsequent outcome. With the belief that considering amotivation as a multidimensional construct could reflect the complexity of motivational deficits in physical education, we developed this study to validate an amotivation…

  2. Physical multiscale modeling and numerical simulation of electrochemical devices for energy conversion and storage from theory to engineering to practice

    CERN Document Server

    Franco, Alejandro A; Bessler, Wolfgang G

    2015-01-01

    This book reviews the use of innovative physical multiscale modeling methods to deeply understand the electrochemical mechanisms and numerically simulate the structure and properties of electrochemical devices for energy storage and conversion.

  3. Toward a mineral physics reference model for the Moon's core.

    Science.gov (United States)

    Antonangeli, Daniele; Morard, Guillaume; Schmerr, Nicholas C; Komabayashi, Tetsuya; Krisch, Michael; Fiquet, Guillaume; Fei, Yingwei

    2015-03-31

    The physical properties of iron (Fe) at high pressure and high temperature are crucial for understanding the chemical composition, evolution, and dynamics of planetary interiors. Indeed, the inner structures of the telluric planets all share a similar layered nature: a central metallic core composed mostly of iron, surrounded by a silicate mantle, and a thin, chemically differentiated crust. To date, most studies of iron have focused on the hexagonal closed packed (hcp, or ε) phase, as ε-Fe is likely stable across the pressure and temperature conditions of Earth's core. However, at the more moderate pressures characteristic of the cores of smaller planetary bodies, such as the Moon, Mercury, or Mars, iron takes on a face-centered cubic (fcc, or γ) structure. Here we present compressional and shear wave sound velocity and density measurements of γ-Fe at high pressures and high temperatures, which are needed to develop accurate seismic models of planetary interiors. Our results indicate that the seismic velocities proposed for the Moon's inner core by a recent reanalysis of Apollo seismic data are well below those of γ-Fe. Our dataset thus provides strong constraints to seismic models of the lunar core and cores of small telluric planets. This allows us to propose a direct compositional and velocity model for the Moon's core.

  4. The Effect of Using Virtual Laboratory on Grade 10 Students' Conceptual Understanding and Their Attitudes towards Physics

    Science.gov (United States)

    Faour, Malak Abou; Ayoubi, Zalpha

    2018-01-01

    This study investigated the effect of using (VL) on grade 10 students' conceptual understanding of the direct current electric circuit and their attitudes towards physics. The research used a quantitative experimental approach. The sample of the study was formed of 50 students of the tenth grade, aged 14 to 16 years old, of an official secondary…

  5. Physics-Based Modeling of Meteor Entry and Breakup

    Science.gov (United States)

    Prabhu, Dinesh K.; Agrawal, Parul; Allen, Gary A., Jr.; Bauschlicher, Charles W., Jr.; Brandis, Aaron M.; Chen, Yih-Kang; Jaffe, Richard L.; Palmer, Grant E.; Saunders, David A.; Stern, Eric C.; hide

    2015-01-01

    A new research effort at NASA Ames Research Center has been initiated in Planetary Defense, which integrates the disciplines of planetary science, atmospheric entry physics, and physics-based risk assessment. This paper describes work within the new program and is focused on meteor entry and breakup.Over the last six decades significant effort was expended in the US and in Europe to understand meteor entry including ablation, fragmentation and airburst (if any) for various types of meteors ranging from stony to iron spectral types. These efforts have produced primarily empirical mathematical models based on observations. Weaknesses of these models, apart from their empiricism, are reliance on idealized shapes (spheres, cylinders, etc.) and simplified models for thermal response of meteoritic materials to aerodynamic and radiative heating. Furthermore, the fragmentation and energy release of meteors (airburst) is poorly understood.On the other hand, flight of human-made atmospheric entry capsules is well understood. The capsules and their requisite heatshields are designed and margined to survive entry. However, the highest speed Earth entry for capsules is 13 kms (Stardust). Furthermore, Earth entry capsules have never exceeded diameters of 5 m, nor have their peak aerothermal environments exceeded 0.3 atm and 1 kW/sq cm. The aims of the current work are: (i) to define the aerothermal environments for objects with entry velocities from 13 to 20 kms; (ii) to explore various hypotheses of fragmentation and airburst of stony meteors in the near term; (iii) to explore the possibility of performing relevant ground-based tests to verify candidate hypotheses; and (iv) to quantify the energy released in airbursts. The results of the new simulations will be used to anchor said risk assessment analyses. With these aims in mind, state-of-the-art entry capsule design tools are being extended for meteor entries. We describe: (i) applications of current simulation tools to

  6. Virtual Physics Laboratory Application Based on the Android Smartphone to Improve Learning Independence and Conceptual Understanding

    Science.gov (United States)

    Arista, Fitra Suci; Kuswanto, Heru

    2018-01-01

    The research study concerned here was to: (1) produce a virtual physics laboratory application to be called ViPhyLab by using the Android smartphone as basis; (2) determine the appropriateness and quality of the virtual physics laboratory application that had been developed; and (3) describe the improvement in learning independence and conceptual…

  7. One-to-One Mobile Technology in High School Physics Classrooms: Understanding Its Use and Outcome

    Science.gov (United States)

    Zhai, Xiaoming; Zhang, Meilan; Li, Min

    2018-01-01

    This study examined ways in which high school students used mobile devices in physics classrooms and after school, and the impact of in-class and after-school mobile technology use on their physics learning performance and interest. We collected data from 803 high school freshmen in China after they had used mobile devices for over five months. A…

  8. Understanding the physical activity promotion behaviours of podiatrists: a qualitative study.

    Science.gov (United States)

    Crisford, Paul; Winzenberg, Tania; Venn, Alison; Cleland, Verity

    2013-09-09

    Health professionals are encouraged to play a part in reducing the health risks of physical inactivity. Little is known of the physical activity promotion practice behaviours of podiatrists. We performed 20 semi-structured interviews with purposefully selected podiatrists to explore their physical activity promotion attitudes, beliefs, knowledge and practice. Transcribed interviews were coded using an iterative thematic approach to identify major themes and salient beliefs. Overall, the participants had a positive attitude to physical activity promotion, considering it a normal part of their role. They saw their role as giving information, encouraging activity and making recommendations, however in practice they were less inclined to follow up on recommendations, monitor activity levels or document the process. Their approach was generally opportunistic, informal and unstructured and the content of assessment and promotion dependent upon the presenting patient's condition. Advice tended to be tailored to the patient's capabilities and interests. They considered there are opportunities to promote physical activity during regular consultations, however, were more likely to do so in patients with chronic diseases such as diabetes. Main barriers to physical activity promotion included unreceptive and unmotivated patients as well as a lack of time, skills and resources. Physical activity promotion appears feasible in podiatry practice in terms of opportunity and acceptability to practitioners, but there is scope for improvement. Strategies to improve promotion need to consider the major issues, barriers and opportunities as well as provide a more structured approach to physical activity promotion by podiatrists.

  9. Pre-Service Physics Teachers' Difficulties in Understanding Special Relativity Topics

    Science.gov (United States)

    Ünlü Yavas, Pervin; Kizilcik, Hasan Sahin

    2016-01-01

    The aim of this study is to identify the reasons why pre-service physics teachers have difficulties related to special relativity topics. In this study conducted with 25 pre-service physics teachers, the case study method, which is a qualitative research method, was used. Interviews were held with the participants about their reasons for…

  10. Understanding Middle School Students' Perceptions of Physics Using Girl-Friendly and Integrated STEM Strategies: A Gender Study

    Science.gov (United States)

    Dare, Emily Anna

    According to the American Physical Society, women accounted for only 20% of bachelor's degrees in the fields of physics and engineering in 2010. This low percentage is likely related to young girls' K-12 education experiences, particularly their experiences prior to high school, during which time young women's perceptions of Science, Technology, Engineering, and Math (STEM) and STEM careers are formed (Catsambis, 1995; Maltese & Tai, 2011; National Research Council, 2012; Sadler, Sonnert, Hazari, & Tai, 2012; Tai, Liu, Maltese, & Fan, 2006; Scantlebury, 2014; Sikora & Pokropek, 2012). There are no significant gender differences in academic achievement in middle school, yet young women have less positive attitudes towards careers in science than their male peers (Catsambis, 1995; Scantlebury, 2014). This suggests that the low female representation in certain STEM fields is a result of not their abilities, but their perceptions; for fields like physics where negative perceptions persist (Haussler & Hoffman, 2002; Labudde, Herzog, Neuenschander, Violi, & Gerber, 2000), it is clear that middle school is a critical time to intervene. This study examines the perceptions of 6th grade middle school students regarding physics and physics-related careers. A theoretical framework based on the literature of girl-friendly and integrated STEM strategies (Baker & Leary, 1995; Halpern et al., 2007; Haussler & Hoffman, 2000, 2002; Labudde et al., 2000; Moore et al., 2014b; Newbill & Cennamo, 2008; Rosser, 2000; Yanowitz, 2004) guided this work to understand how these instructional strategies may influence student's perceptions of physics for both girls and boys. The overarching goal of this work was to understand similarities and differences between girls' and boys' perceptions about physics and physics-related careers. This convergent parallel mixed-methods study uses a series of student surveys and focus group interviews to identify and understand these similarities and

  11. MUSiC - A model unspecific search for new physics in CMS

    Energy Technology Data Exchange (ETDEWEB)

    Biallass, Philipp; Hof, Carsten; Hebbeker, Thomas; Meyer, Arnd [III. Physics Institute A, RWTH Aachen (Germany)

    2008-07-01

    With the start-up of the Large Hadron Collider in 2008 particle physics will enter an unknown territory. New physics is predicted to appear in these regimes by various extensions of the Standard Model such as Supersymmetry or Extra-Dimensions, but it is still unknown how exactly nature has realized such models. Therefore also the most promising signature to detect New Physics is unclear at the moment. In this context we will present a generic search strategy which aims to cover a variety of promising final state topologies without biasing itself to some expected signal. The Model Unspecific Search in CMS (MUSiC) algorithm tries to systematically compare recorded data with expectations from the Standard Model. Thus it is sensitive to deviations caused by New Physics, discrepancies caused by an imperfect simulation and differences due to a lack of understanding of the CMS detector. All three points will be equally important during the months of first data taking.

  12. Urban Adolescents’ Physical Activity Experience, Physical Activity Levels, and Use of Screen-Based Media during Leisure Time: A Structural Model

    Directory of Open Access Journals (Sweden)

    Hui Xie

    2018-01-01

    Full Text Available There is limited understanding of the relationship between physical activity and use of screen-based media, two important behaviors associated with adolescents’ health outcomes. To understand this relationship, researchers may need to consider not only physical activity level but also physical activity experience (i.e., affective experience obtained from doing physical activity. Using a sample predominantly consisting of African and Latino American urban adolescents, this study examined the interrelationships between physical activity experience, physical activity level, and use of screen-based media during leisure time. Data collected using self-report, paper and pencil surveys was analyzed using structural equation modeling. Results showed that physical activity experience was positively associated with physical activity level and had a direct negative relationship with use of non-active video games for males and a direct negative relationship with use of computer/Internet for both genders, after controlling for physical activity level. Physical activity level did not have a direct relationship with use of non-active video games or computer/Internet. However, physical activity level had a direct negative association with use of TV/movies. This study suggests that physical activity experience may play an important role in promoting physical activity and thwarting use of screen-based media among adolescents.

  13. Urban Adolescents’ Physical Activity Experience, Physical Activity Levels, and Use of Screen-Based Media during Leisure Time: A Structural Model

    Science.gov (United States)

    Xie, Hui; Scott, Jason L.; Caldwell, Linda L.

    2018-01-01

    There is limited understanding of the relationship between physical activity and use of screen-based media, two important behaviors associated with adolescents’ health outcomes. To understand this relationship, researchers may need to consider not only physical activity level but also physical activity experience (i.e., affective experience obtained from doing physical activity). Using a sample predominantly consisting of African and Latino American urban adolescents, this study examined the interrelationships between physical activity experience, physical activity level, and use of screen-based media during leisure time. Data collected using self-report, paper and pencil surveys was analyzed using structural equation modeling. Results showed that physical activity experience was positively associated with physical activity level and had a direct negative relationship with use of non-active video games for males and a direct negative relationship with use of computer/Internet for both genders, after controlling for physical activity level. Physical activity level did not have a direct relationship with use of non-active video games or computer/Internet. However, physical activity level had a direct negative association with use of TV/movies. This study suggests that physical activity experience may play an important role in promoting physical activity and thwarting use of screen-based media among adolescents. PMID:29410634

  14. Hybrid computer modelling in plasma physics

    International Nuclear Information System (INIS)

    Hromadka, J; Ibehej, T; Hrach, R

    2016-01-01

    Our contribution is devoted to development of hybrid modelling techniques. We investigate sheath structures in the vicinity of solids immersed in low temperature argon plasma of different pressures by means of particle and fluid computer models. We discuss the differences in results obtained by these methods and try to propose a way to improve the results of fluid models in the low pressure area. There is a possibility to employ Chapman-Enskog method to find appropriate closure relations of fluid equations in a case when particle distribution function is not Maxwellian. We try to follow this way to enhance fluid model and to use it in hybrid plasma model further. (paper)

  15. Physical models of biological information and adaptation.

    Science.gov (United States)

    Stuart, C I

    1985-04-07

    The bio-informational equivalence asserts that biological processes reduce to processes of information transfer. In this paper, that equivalence is treated as a metaphor with deeply anthropomorphic content of a sort that resists constitutive-analytical definition, including formulation within mathematical theories of information. It is argued that continuance of the metaphor, as a quasi-theoretical perspective in biology, must entail a methodological dislocation between biological and physical science. It is proposed that a general class of functions, drawn from classical physics, can serve to eliminate the anthropomorphism. Further considerations indicate that the concept of biological adaptation is central to the general applicability of the informational idea in biology; a non-anthropomorphic treatment of adaptive phenomena is suggested in terms of variational principles.

  16. Understanding Elementary Astronomy by Making Drawing-Based Models

    NARCIS (Netherlands)

    van Joolingen, Wouter; Aukes, A.V.A.; Gijlers, Aaltje H.; Bollen, Lars

    2015-01-01

    Modeling is an important approach in the teaching and learning of science. In this study, we attempt to bring modeling within the reach of young children by creating the SimSketch modeling system, which is based on freehand drawings that can be turned into simulations. This system was used by 247

  17. Understanding Elementary Astronomy by Making Drawing-Based Models

    Science.gov (United States)

    van Joolingen, W. R.; Aukes, Annika V.; Gijlers, H.; Bollen, L.

    2015-01-01

    Modeling is an important approach in the teaching and learning of science. In this study, we attempt to bring modeling within the reach of young children by creating the SimSketch modeling system, which is based on freehand drawings that can be turned into simulations. This system was used by 247 children (ages ranging from 7 to 15) to create a…

  18. Understanding virtual world usage : A multipurpose model and empirical testing

    NARCIS (Netherlands)

    Verhagen, Tibert; Feldberg, Frans; Van Den Hooff, Bart; Meents, Selmar

    2009-01-01

    This study reports an attempt to enhance our understanding of the reasons behind virtual world usage. By providing a mixture of utilitarian and hedonic value, virtual worlds represent an emerging class of multipurpose information systems (MPIS). Previous research seems to fall short in explaining

  19. Scientific Models Help Students Understand the Water Cycle

    Science.gov (United States)

    Forbes, Cory; Vo, Tina; Zangori, Laura; Schwarz, Christina

    2015-01-01

    The water cycle is a large, complex system that encompasses ideas across the K-12 science curriculum. By the time students leave fifth grade, they should understand "that a system is a group of related parts that make up a whole and can carry out functions its individual parts cannot" and be able to describe both components and processes…

  20. Physical models of semiconductor quantum devices

    CERN Document Server

    Fu, Ying

    2013-01-01

    The science and technology relating to nanostructures continues to receive significant attention for its applications to various fields including microelectronics, nanophotonics, and biotechnology. This book describes the basic quantum mechanical principles underlining this fast developing field. From the fundamental principles of quantum mechanics to nanomaterial properties, from device physics to research and development of new systems, this title is aimed at undergraduates, graduates, postgraduates, and researchers.

  1. Model of future officers' availability to the management physical training

    Directory of Open Access Journals (Sweden)

    Olkhovy O.M.

    2012-03-01

    Full Text Available A purpose of work is creation of model of readiness of graduating student to implementation of official questions of guidance, organization and leadthrough of physical preparation in the process of military-professional activity. An analysis is conducted more than 40 sources and questionnaire questioning of a 21 expert. For introduction of model to the system of physical preparation of students the list of its basic constituents is certain: theoretical methodical readiness; functionally-physical readiness; organizationally-administrative readiness. It is certain that readiness of future officers to military-professional activity foresees determination of level of forming of motive capabilities, development of general physical qualities.

  2. Comparison Study on Low Energy Physics Model of GEANT4

    International Nuclear Information System (INIS)

    Park, So Hyun; Jung, Won Gyun; Suh, Tae Suk

    2010-01-01

    The Geant4 simulation toolkit provides improved or renewed physics model according to the version. The latest Geant4.9.3 which has been recoded by developers applies inserted Livermore data and renewed physics model to the low energy electromagnetic physics model. And also, Geant4.9.3 improved the physics factors by modified code. In this study, the stopping power and CSDA(Continuously Slowing Down Approximation) range data of electron or particles were acquired in various material and then, these data were compared with NIST(National Institute of Standards and Technology) data. Through comparison between data of Geant4 simulation and NIST, the improvement of physics model on low energy electromagnetic of Geant4.9.3 was evaluated by comparing the Geant4.9.2

  3. Using Transport Diagnostics to Understand Chemistry Climate Model Ozone Simulations

    Science.gov (United States)

    Strahan, S. E.; Douglass, A. R.; Stolarski, R. S.; Akiyoshi, H.; Bekki, S.; Braesicke, P.; Butchart, N.; Chipperfield, M. P.; Cugnet, D.; Dhomse, S.; hide

    2010-01-01

    We demonstrate how observations of N2O and mean age in the tropical and midlatitude lower stratosphere (LS) can be used to identify realistic transport in models. The results are applied to 15 Chemistry Climate Models (CCMs) participating in the 2010 WMO assessment. Comparison of the observed and simulated N2O/mean age relationship identifies models with fast or slow circulations and reveals details of model ascent and tropical isolation. The use of this process-oriented N2O/mean age diagnostic identifies models with compensating transport deficiencies that produce fortuitous agreement with mean age. We compare the diagnosed model transport behavior with a model's ability to produce realistic LS O3 profiles in the tropics and midlatitudes. Models with the greatest tropical transport problems show the poorest agreement with observations. Models with the most realistic LS transport agree more closely with LS observations and each other. We incorporate the results of the chemistry evaluations in the SPARC CCMVal Report (2010) to explain the range of CCM predictions for the return-to-1980 dates for global (60 S-60 N) and Antarctic column ozone. Later (earlier) Antarctic return dates are generally correlated to higher (lower) vortex Cl(sub y) levels in the LS, and vortex Cl(sub y) is generally correlated with the model's circulation although model Cl(sub y) chemistry or Cl(sub y) conservation can have a significant effect. In both regions, models that have good LS transport produce a smaller range of predictions for the return-to-1980 ozone values. This study suggests that the current range of predicted return dates is unnecessarily large due to identifiable model transport deficiencies.

  4. Physics constrained nonlinear regression models for time series

    International Nuclear Information System (INIS)

    Majda, Andrew J; Harlim, John

    2013-01-01

    A central issue in contemporary science is the development of data driven statistical nonlinear dynamical models for time series of partial observations of nature or a complex physical model. It has been established recently that ad hoc quadratic multi-level regression (MLR) models can have finite-time blow up of statistical solutions and/or pathological behaviour of their invariant measure. Here a new class of physics constrained multi-level quadratic regression models are introduced, analysed and applied to build reduced stochastic models from data of nonlinear systems. These models have the advantages of incorporating memory effects in time as well as the nonlinear noise from energy conserving nonlinear interactions. The mathematical guidelines for the performance and behaviour of these physics constrained MLR models as well as filtering algorithms for their implementation are developed here. Data driven applications of these new multi-level nonlinear regression models are developed for test models involving a nonlinear oscillator with memory effects and the difficult test case of the truncated Burgers–Hopf model. These new physics constrained quadratic MLR models are proposed here as process models for Bayesian estimation through Markov chain Monte Carlo algorithms of low frequency behaviour in complex physical data. (paper)

  5. Physical and mathematical models of communication systems

    International Nuclear Information System (INIS)

    Verkhovskaya, E.P.; Yavorskij, V.V.

    2006-01-01

    The theoretical parties connecting resources of communication system with characteristics of channels are received. The model of such systems from positions quasi-classical thermodynamics is considered. (author)

  6. Applying GPS to enhance understanding of transport-related physical activity.

    Science.gov (United States)

    Duncan, Mitch J; Badland, Hannah M; Mummery, W Kerry

    2009-09-01

    The purpose of the paper is to review the utility of the global positioning system (GPS) in the study of health-related physical activity. The paper draws from existing literature to outline the current work performed using GPS to examine transport-related physical activity, with a focus on the relative utility of the approach when combined with geographic information system (GIS) and other data sources including accelerometers. The paper argues that GPS, especially when used in combination with GIS and accelerometery, offers great promise in objectively measuring and studying the relationship of numerous environmental attributes to human behaviour in terms of physical activity and transport-related activity. Limitations to the use of GPS for the purpose of monitoring health-related physical activity are presented, and recommendations for future avenues of research are discussed.

  7. An Analysis of High School Students' Mental Models of Solid Friction in Physics

    Science.gov (United States)

    Kurnaz, Mehmet Altan; Eksi, Cigdem

    2015-01-01

    Students often have difficulties understanding abstract physics concepts, such as solid friction. This study examines high school students' mental models of solid friction through a case study of 215 high school students in the ninth through twelfth grades. An achievement test with three open-ended questions was created, with questions limited to…

  8. Advancing investigation and physical modeling of first-order fire effects on soils

    Science.gov (United States)

    William J. Massman; John M. Frank; Sacha J. Mooney

    2010-01-01

    Heating soil during intense wildland fires or slash-pile burns can alter the soil irreversibly, resulting in many significant long-term biological, chemical, physical, and hydrological effects. To better understand these long-term effects, it is necessary to improve modeling capability and prediction of the more immediate, or first-order, effects that fire can have on...

  9. Understanding physical activity in spinal cord injury rehabilitation: translating and communicating research through stories.

    Science.gov (United States)

    Smith, Brett; Papathomas, Anthony; Martin Ginis, Kathleen A; Latimer-Cheung, Amy E

    2013-01-01

    The purpose of this article is to develop an evidence-based resource for knowing and communicating the complexities involved for both males and females in implementing and sustaining a physically active lifestyle shortly after spinal cord injury (SCI). Synthesizing a set of qualitative and quantitative studies with over 500 spinal cord injured people, the article represents research utilizing the genre of ethnographic creative non-fiction. This genre of representation holds enormous potential for researchers in terms of disseminating their findings to diverse audiences beyond the academy, and having real impact. The ethnographic creative non-fictions show together for the first time the barriers, determinants, benefits, trajectories, emotions, fears, preferred methods and messengers for delivering important physical activity information to men and women with a SCI. The article contributes to knowledge by showing the embodied complexities involved when in rehabilitation for both males and females in implementing and sustaining a physically active lifestyle shortly after SCI. It also makes a contribution to practice by providing researchers, health care professionals and disability user-groups with a theory and evidence based resource to assist in informing, teaching and enabling people living with SCI to initiate and maintain a physically active lifestyle. Stories may be a highly effective tool to communicate with and to influence spinal cord injured people's activity. The findings of this research showed the many benefits and barriers to developing and sustaining a physically active lifestyle shortly after spinal cord injury. The preferred methods and messengers for delivering physical activity information as well as the activity types, intensities and durations of physical activity for men and women were also shown. Within rehabilitation, spinal cord injured people need to be offered accessible knowledge about how to implement and sustain a physically active

  10. The Open Business Model: Understanding an Emerging Concept

    OpenAIRE

    Weiblen Tobias

    2014-01-01

    Along with the emergence of phenomena such as value co-creation, firm networks, and open innovation, open business models have achieved growing attention in research. Scholars from different fields use the open business model, largely without providing a definition. This has led to an overall lack of clarity of the concept itself. Based on a comprehensive review of scholarly literature in the field, commonalities and differences in the perceived nature of the open business model are carved ou...

  11. Searching for Physics Beyond the Standard Model

    Energy Technology Data Exchange (ETDEWEB)

    Catterall, Simon [Syracuse Univ., NY (United States)

    2016-12-01

    This final report summarizes the work carried out by the Syracuse component of a multi-institutional SciDAC grant led by USQCD. This grant supported software development for theoretical high energy physics. The Syracuse component specifically targeted the development of code for the numerical simulation of N=4 super Yang-Mills theory. The work described in the final report includes this and a summary of results achieve in exploring the structure of this theory. It also describes the personnel - students and a postdoc who were directly or indirectly involved in this project. A list of publication is also described.

  12. A physical model of the evaporating meniscus

    International Nuclear Information System (INIS)

    Mirzamoghadam, A.; Catton, I.

    1985-01-01

    Transport phenomena associated with the heating of a saturated stationary fluid near saturation by an inclined, partially submerged copper plate was studied analytically. Under steady state evaporation, the meniscus profile was derived using an appropriate liquid film velocity and temperature distribution in an integral approach. The solution was then back-substituted in order to identify regions of influence of various physical phenomena given the fluid properties, wall superheat and plate tilt. The degree of superheat and wall tilt were seen to control instability in the meniscus. This instability, connected to the experimental observation of meniscus oscillation, was credited to contributions by liquid inertia and Marangoni convection

  13. A Test of the Fundamental Physics Underlying Exoplanet Climate Models

    Science.gov (United States)

    Beatty, Thomas; Keating, Dylan; Cowan, Nick; Gaudi, Scott; Kataria, Tiffany; Fortney, Jonathan; Stassun, Keivan; Collins, Karen; Deming, Drake; Bell, Taylor; Dang, Lisa; Rogers, Tamara; Colon, Knicole

    2018-05-01

    A fundamental issue in how we understand exoplanet atmospheres is the assumed physical behavior underlying 3D global circulation models (GCMs). Modeling an entire 3D atmosphere is a Herculean task, and so in exoplanet GCMs we generally assume that there are no clouds, no magnetic effects, and chemical equilibrium (e.g., Kataria et al 2016). These simplifying assumptions are computationally necessary, but at the same time their exclusion allows for a large theoretical lee-way when comparing to data. Thus, though significant discrepancies exist between almost all a priori GCM predictions and their corresponding observations, these are assumed to be due to the lack of clouds, or atmospheric drag, or chemical disequilibrium, in the models (e.g., Wong et al. 2016, Stevenson et al. 2017, Lewis et al. 2017, Zhang et al. 2018). Since these effects compete with one another and have large uncertainties, this makes tests of the fundamental physics in GCMs extremely difficult. To rectify this, we propose to use 88.4 hours of Spitzer time to observe 3.6um and 4.5um phase curves of the transiting giant planet KELT-9b. KELT-9b has an observed dayside temperature of 4600K (Gaudi et al. 2017), which means that there will very likely be no clouds on the day- or nightside, and is hot enough that the atmosphere should be close to local chemical equilibrium. Additionally, we plan to leverage KELT-9b's high temperature to make the first measurement of global wind speed on an exoplanet (Bell & Cowan 2018), giving a constraint on atmospheric drag and magnetic effects. Combined, this means KELT-9b is close to a real-world GCM, without most of the effects present on lower temperature planets. Additionally, since KELT-9b orbits an extremely bright host star these will be the highest signal-to-noise ratio phase curves taken with Spitzer by more than a factor of two. This gives us a unique opportunity to make the first precise and direct investigation into the fundamental physics that are the

  14. Learning about physical parameters: the importance of model discrepancy

    International Nuclear Information System (INIS)

    Brynjarsdóttir, Jenný; O'Hagan, Anthony

    2014-01-01

    Science-based simulation models are widely used to predict the behavior of complex physical systems. It is also common to use observations of the physical system to solve the inverse problem, that is, to learn about the values of parameters within the model, a process which is often called calibration. The main goal of calibration is usually to improve the predictive performance of the simulator but the values of the parameters in the model may also be of intrinsic scientific interest in their own right. In order to make appropriate use of observations of the physical system it is important to recognize model discrepancy, the difference between reality and the simulator output. We illustrate through a simple example that an analysis that does not account for model discrepancy may lead to biased and over-confident parameter estimates and predictions. The challenge with incorporating model discrepancy in statistical inverse problems is being confounded with calibration parameters, which will only be resolved with meaningful priors. For our simple example, we model the model-discrepancy via a Gaussian process and demonstrate that through accounting for model discrepancy our prediction within the range of data is correct. However, only with realistic priors on the model discrepancy do we uncover the true parameter values. Through theoretical arguments we show that these findings are typical of the general problem of learning about physical parameters and the underlying physical system using science-based mechanistic models. (paper)

  15. Physical chemistry and modelling of the sintering of actinide oxides

    International Nuclear Information System (INIS)

    Lechelle, Jacques

    2013-01-01

    This report gives a synthesis of the work I have carried out or to which I have numerically contributed to from 1996 up to 2012 in the Department of Plutonium Uranium and minor Actinides in Cadarache CEA Center. Their main goal is the study and the modeling of the sintering process of nuclear fuels which is the unifying thread of this document. Both in order to take into account the physical and chemical features of the actinide bearing oxide material and in order to combine the different transport phenomena leading to sintering, a sub-granular scale model is under development. Extension to a varying chemical composition as well as exchanges with the gaseous phase are foreseen. A simulation on a larger scale (pellet scale) is ongoing in the framework of a PhD thesis. Validation means have been tested with (U,Pu)O 2 material on the scale of the pellet (Small Angle Neutron Diffusion), on the scale of powder granules (X-Ray High Resolution Micro-Tomography) and with CeO 2 at the 'Institut de Chimie Separative' in Marcoule on a single crystal scale (Environmental Scanning Electron Microscope). The required microstructure homogeneity for nuclear fuels has led to a campaign of experimental studies about the role of Cr 2 O 3 as a sintering aid. Whole of these studies improve our understanding of fuel sintering and hence leads to an improved mastering of this process. (author) [fr

  16. The Effect of Math Modeling on Student's Emerging Understanding

    Science.gov (United States)

    Sokolowski, Andrzej

    2015-01-01

    This study investigated the effects of applying mathematical modeling on revising students' preconception of the process of optimizing area enclosed by a string of a fixed length. A group of 28 high school pre-calculus students were immersed in modeling activity that included direct measurements, data collecting, and formulating algebraic…

  17. How to: understanding SWAT model uncertainty relative to measured results

    Science.gov (United States)

    Watershed models are being relied upon to contribute to most policy-making decisions of watershed management, and the demand for an accurate accounting of complete model uncertainty is rising. Generalized likelihood uncertainty estimation (GLUE) is a widely used method for quantifying uncertainty i...

  18. Understanding Rasch Measurement: Partial Credit Model and Pivot Anchoring.

    Science.gov (United States)

    Bode, Rita K.

    2001-01-01

    Describes the Rasch measurement partial credit model, what it is, how it differs from other Rasch models, and when and how to use it. Also describes the calibration of instruments with increasingly complex items. Explains pivot anchoring and illustrates its use and describes the effect of pivot anchoring on step calibrations, item hierarchy, and…

  19. Engineered Barrier System: Physical and Chemical Environment Model

    International Nuclear Information System (INIS)

    Jolley, D. M.; Jarek, R.; Mariner, P.

    2004-01-01

    The conceptual and predictive models documented in this Engineered Barrier System: Physical and Chemical Environment Model report describe the evolution of the physical and chemical conditions within the waste emplacement drifts of the repository. The modeling approaches and model output data will be used in the total system performance assessment (TSPA-LA) to assess the performance of the engineered barrier system and the waste form. These models evaluate the range of potential water compositions within the emplacement drifts, resulting from the interaction of introduced materials and minerals in dust with water seeping into the drifts and with aqueous solutions forming by deliquescence of dust (as influenced by atmospheric conditions), and from thermal-hydrological-chemical (THC) processes in the drift. These models also consider the uncertainty and variability in water chemistry inside the drift and the compositions of introduced materials within the drift. This report develops and documents a set of process- and abstraction-level models that constitute the engineered barrier system: physical and chemical environment model. Where possible, these models use information directly from other process model reports as input, which promotes integration among process models used for total system performance assessment. Specific tasks and activities of modeling the physical and chemical environment are included in the technical work plan ''Technical Work Plan for: In-Drift Geochemistry Modeling'' (BSC 2004 [DIRS 166519]). As described in the technical work plan, the development of this report is coordinated with the development of other engineered barrier system analysis model reports

  20. Understanding the Day Cent model: Calibration, sensitivity, and identifiability through inverse modeling

    Science.gov (United States)

    Necpálová, Magdalena; Anex, Robert P.; Fienen, Michael N.; Del Grosso, Stephen J.; Castellano, Michael J.; Sawyer, John E.; Iqbal, Javed; Pantoja, Jose L.; Barker, Daniel W.

    2015-01-01

    The ability of biogeochemical ecosystem models to represent agro-ecosystems depends on their correct integration with field observations. We report simultaneous calibration of 67 DayCent model parameters using multiple observation types through inverse modeling using the PEST parameter estimation software. Parameter estimation reduced the total sum of weighted squared residuals by 56% and improved model fit to crop productivity, soil carbon, volumetric soil water content, soil temperature, N2O, and soil3NO− compared to the default simulation. Inverse modeling substantially reduced predictive model error relative to the default model for all model predictions, except for soil 3NO− and 4NH+. Post-processing analyses provided insights into parameter–observation relationships based on parameter correlations, sensitivity and identifiability. Inverse modeling tools are shown to be a powerful way to systematize and accelerate the process of biogeochemical model interrogation, improving our understanding of model function and the underlying ecosystem biogeochemical processes that they represent.

  1. Innovative learning model for improving students’ argumentation skill and concept understanding on science

    Science.gov (United States)

    Nafsiati Astuti, Rini

    2018-04-01

    Argumentation skill is the ability to compose and maintain arguments consisting of claims, supports for evidence, and strengthened-reasons. Argumentation is an important skill student needs to face the challenges of globalization in the 21st century. It is not an ability that can be developed by itself along with the physical development of human, but it must be developed under nerve like process, giving stimulus so as to require a person to be able to argue. Therefore, teachers should develop students’ skill of arguing in science learning in the classroom. The purpose of this study is to obtain an innovative learning model that are valid in terms of content and construct in improving the skills of argumentation and concept understanding of junior high school students. The assessment of content validity and construct validity was done through Focus Group Discussion (FGD), using the content and construct validation sheet, book model, learning video, and a set of learning aids for one meeting. Assessment results from 3 (three) experts showed that the learning model developed in the category was valid. The validity itself shows that the developed learning model has met the content requirement, the student needs, state of the art, strong theoretical and empirical foundation and construct validity, which has a connection of syntax stages and components of learning model so that it can be applied in the classroom activities

  2. Towards LHC physics with nonlocal Standard Model

    Energy Technology Data Exchange (ETDEWEB)

    Biswas, Tirthabir, E-mail: tbiswas@loyno.edu [Department of Physics, Loyola University, 6363 St. Charles Avenue, Box 92, New Orleans, LA 70118 (United States); Okada, Nobuchika, E-mail: okadan@ua.edu [Department of Physics and Astronomy, University of Alabama, Tuscaloosa, AL 35487-0324 (United States)

    2015-09-15

    We take a few steps towards constructing a string-inspired nonlocal extension of the Standard Model. We start by illustrating how quantum loop calculations can be performed in nonlocal scalar field theory. In particular, we show the potential to address the hierarchy problem in the nonlocal framework. Next, we construct a nonlocal abelian gauge model and derive modifications of the gauge interaction vertex and field propagators. We apply the modifications to a toy version of the nonlocal Standard Model and investigate collider phenomenology. We find the lower bound on the scale of nonlocality from the 8 TeV LHC data to be 2.5–3 TeV.

  3. Darwin model in plasma physics revisited

    International Nuclear Information System (INIS)

    Xie, Huasheng; Zhu, Jia; Ma, Zhiwei

    2014-01-01

    Dispersion relations from the Darwin (a.k.a., magnetoinductive or magnetostatic) model are given and compared with those of the full electromagnetic model. Analytical and numerical solutions show that the errors from the Darwin approximation can be large even if phase velocity for a low-frequency wave is close to or larger than the speed of light. Besides missing two wave branches associated mainly with the electron dynamics, the coupling branch of the electrons and ions in the Darwin model is modified to become a new artificial branch that incorrectly represents the coupling dynamics of the electrons and ions. (paper)

  4. Understanding and forecasting polar stratospheric variability with statistical models

    Directory of Open Access Journals (Sweden)

    C. Blume

    2012-07-01

    Full Text Available The variability of the north-polar stratospheric vortex is a prominent aspect of the middle atmosphere. This work investigates a wide class of statistical models with respect to their ability to model geopotential and temperature anomalies, representing variability in the polar stratosphere. Four partly nonstationary, nonlinear models are assessed: linear discriminant analysis (LDA; a cluster method based on finite elements (FEM-VARX; a neural network, namely the multi-layer perceptron (MLP; and support vector regression (SVR. These methods model time series by incorporating all significant external factors simultaneously, including ENSO, QBO, the solar cycle, volcanoes, to then quantify their statistical importance. We show that variability in reanalysis data from 1980 to 2005 is successfully modeled. The period from 2005 to 2011 can be hindcasted to a certain extent, where MLP performs significantly better than the remaining models. However, variability remains that cannot be statistically hindcasted within the current framework, such as the unexpected major warming in January 2009. Finally, the statistical model with the best generalization performance is used to predict a winter 2011/12 with warm and weak vortex conditions. A vortex breakdown is predicted for late January, early February 2012.

  5. Principles of Physical Modelling of Unsaturated Soils

    OpenAIRE

    CAICEDO, Bernardo; THOREL, Luc

    2014-01-01

    Centrifuge modelling has been widely used to simulate the performance of a variety of geotechnical works, most of them focusing on saturated clays or dry sands. On the other hand, the performance of some geotechnical works depends on the behaviour of shallow layers in the soil deposit where it is frequently unsaturated. Centrifuge modelling could be a powerful tool to study the performance of shallow geotechnical works. However all the experimental complexities related to unsaturated soils, w...

  6. Using Modeling and Simulation to Complement Testing for Increased Understanding of Weapon Subassembly Response.

    Energy Technology Data Exchange (ETDEWEB)

    Wong, Michael K. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Davidson, Megan [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2017-09-01

    As part of Sandia’s nuclear deterrence mission, the B61-12 Life Extension Program (LEP) aims to modernize the aging weapon system. Modernization requires requalification and Sandia is using high performance computing to perform advanced computational simulations to better understand, evaluate, and verify weapon system performance in conjunction with limited physical testing. The Nose Bomb Subassembly (NBSA) of the B61-12 is responsible for producing a fuzing signal upon ground impact. The fuzing signal is dependent upon electromechanical impact sensors producing valid electrical fuzing signals at impact. Computer generated models were used to assess the timing between the impact sensor’s response to the deceleration of impact and damage to major components and system subassemblies. The modeling and simulation team worked alongside the physical test team to design a large-scale reverse ballistic test to not only assess system performance, but to also validate their computational models. The reverse ballistic test conducted at Sandia’s sled test facility sent a rocket sled with a representative target into a stationary B61-12 (NBSA) to characterize the nose crush and functional response of NBSA components. Data obtained from data recorders and high-speed photometrics were integrated with previously generated computer models in order to refine and validate the model’s ability to reliably simulate real-world effects. Large-scale tests are impractical to conduct for every single impact scenario. By creating reliable computer models, we can perform simulations that identify trends and produce estimates of outcomes over the entire range of required impact conditions. Sandia’s HPCs enable geometric resolution that was unachievable before, allowing for more fidelity and detail, and creating simulations that can provide insight to support evaluation of requirements and performance margins. As computing resources continue to improve, researchers at Sandia are hoping

  7. Stem Cell Models: A Guide to Understand and Mitigate Aging?

    Science.gov (United States)

    Brunauer, Regina; Alavez, Silvestre; Kennedy, Brian K

    2017-01-01

    Aging is studied either on a systemic level using life span and health span of animal models, or on the cellular level using replicative life span of yeast or mammalian cells. While useful in identifying general and conserved pathways of aging, both approaches provide only limited information about cell-type specific causes and mechanisms of aging. Stem cells are the regenerative units of multicellular life, and stem cell aging might be a major cause for organismal aging. Using the examples of hematopoietic stem cell aging and human pluripotent stem cell models, we propose that stem cell models of aging are valuable for studying tissue-specific causes and mechanisms of aging and can provide unique insights into the mammalian aging process that may be inaccessible in simple model organisms. © 2016 S. Karger AG, Basel.

  8. The Benefit of Ambiguity in Understanding Goals in Requirements Modelling

    DEFF Research Database (Denmark)

    Paay, Jeni; Pedell, Sonja; Sterling, Leon

    2011-01-01

    This paper examines the benefit of ambiguity in describing goals in requirements modelling for the design of socio-technical systems using concepts from Agent-Oriented Software Engineering (AOSE) and ethnographic and cultural probe methods from Human Computer Interaction (HCI). The authors’ aim...... ambiguity in the process of elicitation and analysis through the use of empirically informed quality goals attached to functional goals. The authors demonstrate the benefit of articulating a quality goal without turning it into a functional goal. Their study shows that quality goals kept at a high level...... of abstraction, ambiguous and open for conversations through the modelling process add richness to goal models, and communicate quality attributes of the interaction being modelled to the design phase, where this ambiguity is regarded as a resource for design....

  9. Assessing Understanding of Biological Processes: Elucidating Students' Models of Meiosis.

    Science.gov (United States)

    Kindfield, Ann C.

    1994-01-01

    Presents a meiosis reasoning problem that provides direct access to students' current models of chromosomes and meiosis. Also included in the article are tips for classroom implementation and a summary of the solution evaluation. (ZWH)

  10. Understanding and scaffolding Danish schoolteachers' motivation for using classroom-based physical activity

    DEFF Research Database (Denmark)

    Knudsen, Louise Stjerne; Skovgaard, Thomas; Bredahl, Thomas

    2018-01-01

    INTRODUCTION: The benefits of physical activity for children's health, both mental and physical, and its positive effects on academic achievement are well established. Research also emphasises that schools could provide a natural setting for regular physical activity. There is, however, a limited......: The study uses an explanatory sequential mixed-methods design. Schools from across Denmark are included in the sample. The design comprises two separated phases-a quantitative and qualitative phase. The quantitative phase is guided by the self-determination theory where teachers' motivation will be measured...... have been acquired. All participants in this study will provide written informed consent prior to data collection. All data emerging from the quantitative and qualitative phase will be anonymised for analysis. Ethics approval was requested from the Regional Committee on Health Research Ethics...

  11. A physics department's role in preparing physics teachers: The Colorado learning assistant model

    Science.gov (United States)

    Otero, Valerie; Pollock, Steven; Finkelstein, Noah

    2010-11-01

    In response to substantial evidence that many U.S. students are inadequately prepared in science and mathematics, we have developed an effective and adaptable model that improves the education of all students in introductory physics and increases the numbers of talented physics majors becoming certified to teach physics. We report on the Colorado Learning Assistant model and discuss its effectiveness at a large research university. Since its inception in 2003, we have increased the pool of well-qualified K-12 physics teachers by a factor of approximately three, engaged scientists significantly in the recruiting and preparation of future teachers, and improved the introductory physics sequence so that students' learning gains are typically double the traditional average.

  12. Understanding Gulf War Illness: An Integrative Modeling Approach

    Science.gov (United States)

    2017-10-01

    using a novel mathematical model. The computational biology approach will enable the consortium to quickly identify targets of dysfunction and find... computer / mathematical paradigms for evaluation of treatment strategies 12-30 50% Develop pilot clinical trials on basis of animal studies 24-36 60...the goal of testing chemical treatments. The immune and autonomic biomarkers will be tested using a computational modeling approach allowing for a

  13. Improving Students' Understanding of Molecular Structure through Broad-Based Use of Computer Models in the Undergraduate Organic Chemistry Lecture

    Science.gov (United States)

    Springer, Michael T.

    2014-01-01

    Several articles suggest how to incorporate computer models into the organic chemistry laboratory, but relatively few papers discuss how to incorporate these models broadly into the organic chemistry lecture. Previous research has suggested that "manipulating" physical or computer models enhances student understanding; this study…

  14. On the role of model structure in hydrological modeling : Understanding models

    NARCIS (Netherlands)

    Gharari, S.

    2016-01-01

    Modeling is an essential part of the science of hydrology. Models enable us to formulate what we know and perceive from the real world into a neat package. Rainfall-runoff models are abstract simplifications of how a catchment works. Within the research field of scientific rainfall-runoff modeling,

  15. Searches for physics beyond the Standard Model at the Tevatron

    Indian Academy of Sciences (India)

    Publications ... Beyond Standard Model Physics Volume 79 Issue 4 October 2012 pp 703-717 ... a centre-of-mass energy of 1.96 TeV that the CDF and DO Collaborations have scrutinized looking for new physics in a wide range of final states.

  16. Multiphysics software and the challenge to validating physical models

    International Nuclear Information System (INIS)

    Luxat, J.C.

    2008-01-01

    This paper discusses multi physics software and validation of physical models in the nuclear industry. The major challenge is to convert the general purpose software package to a robust application-specific solution. This requires greater knowledge of the underlying solution techniques and the limitations of the packages. Good user interfaces and neat graphics do not compensate for any deficiencies

  17. The Dawn of physics beyond the standard model

    CERN Multimedia

    Kane, Gordon

    2003-01-01

    "The Standard Model of particle physics is at a pivotal moment in its history: it is both at the height of its success and on the verge of being surpassed [...] A new era in particle physics could soon be heralded by the detection of supersymmetric particles at the Tevatron collider at Fermi National Accelerator Laboratory in Batavia, Ill." (8 pages)

  18. Simple suggestions for including vertical physics in oil spill models

    International Nuclear Information System (INIS)

    D'Asaro, Eric; University of Washington, Seatle, WA

    2001-01-01

    Current models of oil spills include no vertical physics. They neglect the effect of vertical water motions on the transport and concentration of floating oil. Some simple ways to introduce vertical physics are suggested here. The major suggestion is to routinely measure the density stratification of the upper ocean during oil spills in order to develop a database on the effect of stratification. (Author)

  19. The Standard Model and Higgs physics

    Science.gov (United States)

    Torassa, Ezio

    2018-05-01

    The Standard Model is a consistent and computable theory that successfully describes the elementary particle interactions. The strong, electromagnetic and weak interactions have been included in the theory exploiting the relation between group symmetries and group generators, in order to smartly introduce the force carriers. The group properties lead to constraints between boson masses and couplings. All the measurements performed at the LEP, Tevatron, LHC and other accelerators proved the consistency of the Standard Model. A key element of the theory is the Higgs field, which together with the spontaneous symmetry breaking, gives mass to the vector bosons and to the fermions. Unlike the case of vector bosons, the theory does not provide prediction for the Higgs boson mass. The LEP experiments, while providing very precise measurements of the Standard Model theory, searched for the evidence of the Higgs boson until the year 2000. The discovery of the top quark in 1994 by the Tevatron experiments and of the Higgs boson in 2012 by the LHC experiments were considered as the completion of the fundamental particles list of the Standard Model theory. Nevertheless the neutrino oscillations, the dark matter and the baryon asymmetry in the Universe evidence that we need a new extended model. In the Standard Model there are also some unattractive theoretical aspects like the divergent loop corrections to the Higgs boson mass and the very small Yukawa couplings needed to describe the neutrino masses. For all these reasons, the hunt of discrepancies between Standard Model and data is still going on with the aim to finally describe the new extended theory.

  20. Teaching Climate Change Using System Models: An Understanding Global Change Project Pilot Study

    Science.gov (United States)

    Bean, J. R.; Stuhlsatz, M.; Bracey, Z. B.; Marshall, C. R.

    2017-12-01

    Teaching and learning about historical and anthropogenic climate change in the classroom requires integrating instructional resources that address physical, chemical, and biological processes. The Understanding Global Change (UGC) framework and system models developed at the University of California Museum of Paleontology (UCMP) provide visualizations of the relationships and feedbacks between Earth system processes, and the consequences of anthropogenic activities on global climate. This schema provides a mechanism for developing pedagogic narratives that are known to support comprehension and retention of information and relationships. We designed a nine-day instructional unit for middle and high school students that includes a sequence of hands-on, inquiry-based, data rich activities combined with conceptual modeling exercises intended to foster students' development of systems thinking and their understanding of human influences on Earth system processes. The pilot unit, Sea Level Rise in the San Francisco Bay Area, addresses the human causes and consequences of sea level rise and related Earth system processes (i.e., the water cycle and greenhouse effect). Most of the content is not Bay Area specific, and could be used to explore sea level rise in any coastal region. Students completed pre and post assessments, which included questions about the connectedness of components of the Earth system and probed their attitudes towards participating in environmental stewardship activities. Students sequentially drew models representing the content explored in the activities and wrote short descriptions of their system diagrams that were collected by teachers for analysis. We also randomly assigned classes to engage in a very short additional intervention that asked students to think about the role that humans play in the Earth system and to draw themselves into the models. The study will determine if these students have higher stewardship scores and more frequently

  1. Propulsion Physics Under the Changing Density Field Model

    Science.gov (United States)

    Robertson, Glen A.

    2011-01-01

    To grow as a space faring race, future spaceflight systems will requires new propulsion physics. Specifically a propulsion physics model that does not require mass ejection without limiting the high thrust necessary to accelerate within or beyond our solar system and return within a normal work period or lifetime. In 2004 Khoury and Weltman produced a density dependent cosmology theory they called Chameleon Cosmology, as at its nature, it is hidden within known physics. This theory represents a scalar field within and about an object, even in the vacuum. Whereby, these scalar fields can be viewed as vacuum energy fields with definable densities that permeate all matter; having implications to dark matter/energy with universe acceleration properties; implying a new force mechanism for propulsion physics. Using Chameleon Cosmology, the author has developed a new propulsion physics model, called the Changing Density Field (CDF) Model. This model relates to density changes in these density fields, where the density field density changes are related to the acceleration of matter within an object. These density changes in turn change how an object couples to the surrounding density fields. Whereby, thrust is achieved by causing a differential in the coupling to these density fields about an object. Since the model indicates that the density of the density field in an object can be changed by internal mass acceleration, even without exhausting mass, the CDF model implies a new propellant-less propulsion physics model

  2. Physically representative atomistic modeling of atomic-scale friction

    Science.gov (United States)

    Dong, Yalin

    Nanotribology is a research field to study friction, adhesion, wear and lubrication occurred between two sliding interfaces at nano scale. This study is motivated by the demanding need of miniaturization mechanical components in Micro Electro Mechanical Systems (MEMS), improvement of durability in magnetic storage system, and other industrial applications. Overcoming tribological failure and finding ways to control friction at small scale have become keys to commercialize MEMS with sliding components as well as to stimulate the technological innovation associated with the development of MEMS. In addition to the industrial applications, such research is also scientifically fascinating because it opens a door to understand macroscopic friction from the most bottom atomic level, and therefore serves as a bridge between science and engineering. This thesis focuses on solid/solid atomic friction and its associated energy dissipation through theoretical analysis, atomistic simulation, transition state theory, and close collaboration with experimentalists. Reduced-order models have many advantages for its simplification and capacity to simulating long-time event. We will apply Prandtl-Tomlinson models and their extensions to interpret dry atomic-scale friction. We begin with the fundamental equations and build on them step-by-step from the simple quasistatic one-spring, one-mass model for predicting transitions between friction regimes to the two-dimensional and multi-atom models for describing the effect of contact area. Theoretical analysis, numerical implementation, and predicted physical phenomena are all discussed. In the process, we demonstrate the significant potential for this approach to yield new fundamental understanding of atomic-scale friction. Atomistic modeling can never be overemphasized in the investigation of atomic friction, in which each single atom could play a significant role, but is hard to be captured experimentally. In atomic friction, the

  3. Simple mathematical models of symmetry breaking. Application to particle physics

    International Nuclear Information System (INIS)

    Michel, L.

    1976-01-01

    Some mathematical facts relevant to symmetry breaking are presented. A first mathematical model deals with the smooth action of compact Lie groups on real manifolds, a second model considers linear action of any group on real or complex finite dimensional vector spaces. Application of the mathematical models to particle physics is considered. (B.R.H.)

  4. Standard model Higgs physics at colliders

    International Nuclear Information System (INIS)

    Rosca, A.

    2007-01-01

    In this report we briefly review the experimental status and prospects to verify the Higgs mechanism of spontaneous symmetry breaking. The focus is on the most relevant aspects of the phenomenology of the Standard Model Higgs boson at current (Tevatron) and future (Large Hadron Collider, LHC and International Linear Collider, ILC) particle colliders. We review the Standard Model searches: searches at the Tevatron, the program planned at the LHC and prospects at the ILC. Emphasis is put on what follows after a candidate discovery at the LHC: the various measurements which are necessary to precisely determine what the properties of this Higgs candidate are. (author)

  5. Understanding Mammalian Germ Line Development with In Vitro Models.

    Science.gov (United States)

    Martínez-Arroyo, Ana M; Míguez-Forján, Jose M; Remohí, Jose; Pellicer, Antonio; Medrano, Jose V

    2015-09-15

    Germ line development is crucial in organisms with sexual reproduction to complete their life cycle. In mammals, knowledge about germ line development is based mainly on the mouse model, in which genetic and epigenetic events are well described. However, little is known about how germ line development is orchestrated in humans, especially in the earliest stages. New findings derived from human in vitro models to obtain germ cells can shed light on these questions. This comprehensive review summarizes the current knowledge about mammalian germ line development, emphasizing the state of the art obtained from in vitro models for germ cell-like cell derivation. Current knowledge of the pluripotency cycle and germ cell specification has allowed different in vitro strategies to obtain germ cells with proven functionality in mouse models. Several reports during the last 10 years show that in vitro germ cell derivation with proven functionality to generate a healthy offspring is possible in mice. However, differences in the embryo development and pluripotency potential between human and mouse make it difficult to extrapolate these results. Further efforts on both human and mouse in vitro models to obtain germ cells from pluripotent stem cells may help to elucidate how human physiological events take place; therefore, therapeutic strategies can also be considered.

  6. Travelling wave solutions to nonlinear physical models by means of ...

    Indian Academy of Sciences (India)

    Abstract. This paper presents the first integral method to carry out the integration of nonlinear ... NPDEs is an important and attractive research area. Not all ... cial types of analytic solutions to understand biological, physical and chemical phenomena ... Thus, based on the qualitative theory of ordinary differential equations.

  7. Physics-Based Pneumatic Hammer Instability Model, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — The objective of this project is to develop a physics-based pneumatic hammer instability model that accurately predicts the stability of hydrostatic bearings...

  8. Overview of the Higgs and Standard Model physics at ATLAS

    CERN Document Server

    Vazquez Schroeder, Tamara; The ATLAS collaboration

    2018-01-01

    This talk presents selected aspects of recent physics results from the ATLAS collaboration in the Standard Model and Higgs sectors, with a focus on the recent evidence for the associated production of the Higgs boson and a top quark pair.

  9. Can plane wave modes be physical modes in soliton models?

    International Nuclear Information System (INIS)

    Aldabe, F.

    1995-08-01

    I show that plane waves may not be used as asymptotic states in soliton models because they describe unphysical states. When asymptotic states are taken to the physical there is not T-matrix of O(1). (author). 9 refs

  10. Physical characterization and kinetic modelling of matrix tablets of ...

    African Journals Online (AJOL)

    release mechanisms were characterized by kinetic modeling. Analytical ... findings demonstrate that both the desired physical characteristics and drug release profiles were obtained ..... on the compression, mechanical, and release properties.

  11. Standard model status (in search of ''new physics'')

    International Nuclear Information System (INIS)

    Marciano, W.J.

    1993-03-01

    A perspective on successes and shortcomings of the standard model is given. The complementarity between direct high energy probes of new physics and lower energy searches via precision measurements and rare reactions is described. Several illustrative examples are discussed

  12. Upper Secondary Students' Understanding of the Basic Physical Interactions in Analogous Atomic and Solar Systems

    Science.gov (United States)

    Taber, Keith S.

    2013-01-01

    Comparing the atom to a "tiny solar system" is a common teaching analogy, and the extent to which learners saw the systems as analogous was investigated. English upper secondary students were asked parallel questions about the physical interactions between the components of a simple atomic system and a simple solar system to investigate…

  13. Understanding the physical attractiveness literature: Qualitative reviews versus meta-analysis.

    Science.gov (United States)

    Feingold, Alan

    2017-01-01

    The target article is a qualitative review of selected findings in the physical attractiveness literature. This commentary explains why the meta-analytic approach, frequently used by other attractiveness reviewers, is preferable for drawing unbiased conclusions about the effects of attractiveness. The article's main contribution is affording a foundation for subsequent meta-analysis of the studies discussed in a subjective fashion.

  14. Understanding the Picture Exchange Communication System and Its Application in Physical Education

    Science.gov (United States)

    Green, Amanda; Sandt, Dawn

    2013-01-01

    This article presents the Picture Exchange Communication System (PECS) and its applications in physical education. The PECS is an appropriate communication intervention for students with autism who lack functional communication skills. It is often confused with other visual support strategies, so the authors delineate the six phases of PECS and…

  15. Investigating and improving student understanding of the probability distributions for measuring physical observables in quantum mechanics

    International Nuclear Information System (INIS)

    Marshman, Emily; Singh, Chandralekha

    2017-01-01

    A solid grasp of the probability distributions for measuring physical observables is central to connecting the quantum formalism to measurements. However, students often struggle with the probability distributions of measurement outcomes for an observable and have difficulty expressing this concept in different representations. Here we first describe the difficulties that upper-level undergraduate and PhD students have with the probability distributions for measuring physical observables in quantum mechanics. We then discuss how student difficulties found in written surveys and individual interviews were used as a guide in the development of a quantum interactive learning tutorial (QuILT) to help students develop a good grasp of the probability distributions of measurement outcomes for physical observables. The QuILT strives to help students become proficient in expressing the probability distributions for the measurement of physical observables in Dirac notation and in the position representation and be able to convert from Dirac notation to position representation and vice versa. We describe the development and evaluation of the QuILT and findings about the effectiveness of the QuILT from in-class evaluations. (paper)

  16. Understanding healing environments : effects of physical environmental stimuli on patients' health and well-being

    NARCIS (Netherlands)

    Dijkstra, K.

    2009-01-01

    The research in this dissertation contributes to the growing body of evidence that the physical healthcare environment can make a difference in how quickly patients recover or adapt to specific acute and chronic conditions. The concepts of healing environments and evidence-based design are widely

  17. Understanding behavioral mechanisms for physical activity in head and neck cancer patients: a qualitative study

    NARCIS (Netherlands)

    Sealy, Martine; Stuiver, M.M.; Midtgard, Julie; van der Schans, Cees; Roodenburg, Jan L N; Jager-Wittenaar, Harriët

    2017-01-01

    Rationale: Head and neck cancer (HNC) patients often have adverse changes in body composition. Loss of muscle mass and strength frequently occur, even when dietary intake is adequate. Nascent evidence suggests that a healthy lifestyle, including adequate physical activity (PA) and diet, may prevent

  18. Understanding eye movements in face recognition using hidden Markov models.

    Science.gov (United States)

    Chuk, Tim; Chan, Antoni B; Hsiao, Janet H

    2014-09-16

    We use a hidden Markov model (HMM) based approach to analyze eye movement data in face recognition. HMMs are statistical models that are specialized in handling time-series data. We conducted a face recognition task with Asian participants, and model each participant's eye movement pattern with an HMM, which summarized the participant's scan paths in face recognition with both regions of interest and the transition probabilities among them. By clustering these HMMs, we showed that participants' eye movements could be categorized into holistic or analytic patterns, demonstrating significant individual differences even within the same culture. Participants with the analytic pattern had longer response times, but did not differ significantly in recognition accuracy from those with the holistic pattern. We also found that correct and wrong recognitions were associated with distinctive eye movement patterns; the difference between the two patterns lies in the transitions rather than locations of the fixations alone. © 2014 ARVO.

  19. Model uncertainties in top-quark physics

    CERN Document Server

    Seidel, Markus

    2014-01-01

    The ATLAS and CMS collaborations at the Large Hadron Collider (LHC) are studying the top quark in pp collisions at 7 and 8 TeV. Due to the large integrated luminosity, precision measurements of production cross-sections and properties are often limited by systematic uncertainties. An overview of the modeling uncertainties for simulated events is given in this report.

  20. Introduction to physics beyond the Standard Model

    CERN Document Server

    Giudice, Gian Francesco

    1998-01-01

    These lectures will give an introductory review of the main ideas behind the attempts to extend the standard-model description of elementary particle interactions. After analysing the conceptual motivations that lead us to blieve in the existence of an underlying fundamental theory, wi will discuss the present status of various theoretical constructs : grand unification, supersymmetry and technicolour.

  1. Understanding forest-derived biomass supply with GIS modelling

    DEFF Research Database (Denmark)

    Hock, B. K.; Blomqvist, L.; Hall, P.

    2012-01-01

    distribution, and the cost of delivery as forests are frequently remote from energy users. A GIS-based model was developed to predict supply curves of forest biomass material for a site or group of sites, both now and in the future. The GIS biomass supply model was used to assist the New Zealand Energy...... Efficiency and Conservation Authority's development of a national target for biomass use for industrial heat production, to determine potential forest residue volumes for industrial heat and their delivery costs for 19 processing plants of the dairy company Fonterra, and towards investigating options...

  2. Suicidal ideation in prostate cancer survivors: understanding the role of physical and psychological health outcomes.

    Science.gov (United States)

    Recklitis, Christopher J; Zhou, Eric S; Zwemer, Eric K; Hu, Jim C; Kantoff, Philip W

    2014-11-01

    Epidemiological studies have shown prostate cancer (PC) survivors are at an increased risk of suicide compared with the general population, but to the authors' knowledge very little is known regarding what factors are associated with this increased risk. The current study examined the prevalence of suicidal ideation (SI) and its association with cancer treatment and posttreatment physical and emotional health in a cohort of long-term PC survivors. A total of 693 PC survivors (3-8 years after diagnosis) completed a mailed survey on physical and psychological functioning, including cancer treatments, the Short Form-12 (SF-12), the Expanded Prostate Cancer Index Composite Instrument (EPIC-26), a depression rating scale, and 8 items regarding recent suicidal thoughts and behaviors. A total of 86 PC survivors (12.4%) endorsed SI, with 10 individuals (1.4%) reporting serious SI. Serious SI was more common in this sample compared with age-adjusted and sex-adjusted normative data. SI was not associated with most demographic variables, or with PC stage or treatments. However, SI was found to be significantly associated with employment status, poor physical and emotional functioning, greater symptom burden on the EPIC-26, higher frequency of significant pain, and clinically significant depression (P physical and emotional function, including disability status and pain, were found to be associated with SI (P depression. A significant percentage of PC survivors report recent SI, which is associated with both physical and psychological dysfunction, but not PC treatments. The results of the current study help to explain the increased risk of suicide previously reported in PC survivors and have important implications for identifying and treating those survivors at greatest risk of suicidality. © 2014 American Cancer Society.

  3. Ethical Dilemmas: A Model to Understand Teacher Practice

    Science.gov (United States)

    Ehrich, Lisa Catherine; Kimber, Megan; Millwater, Jan; Cranston, Neil

    2011-01-01

    Over recent decades, the field of ethics has been the focus of increasing attention in teaching. This is not surprising given that teaching is a moral activity that is heavily values-laden. Because of this, teachers face ethical dilemmas in the course of their daily work. This paper presents an ethical decision-making model that helps to explain…

  4. Using Modeling Tools to Better Understand Permafrost Hydrology

    Directory of Open Access Journals (Sweden)

    Clément Fabre

    2017-06-01

    Full Text Available Modification of the hydrological cycle and, subsequently, of other global cycles is expected in Arctic watersheds owing to global change. Future climate scenarios imply widespread permafrost degradation caused by an increase in air temperature, and the expected effect on permafrost hydrology is immense. This study aims at analyzing, and quantifying the daily water transfer in the largest Arctic river system, the Yenisei River in central Siberia, Russia, partially underlain by permafrost. The semi-distributed SWAT (Soil and Water Assessment Tool hydrological model has been calibrated and validated at a daily time step in historical discharge simulations for the 2003–2014 period. The model parameters have been adjusted to embrace the hydrological features of permafrost. SWAT is shown capable to estimate water fluxes at a daily time step, especially during unfrozen periods, once are considered specific climatic and soils conditions adapted to a permafrost watershed. The model simulates average annual contribution to runoff of 263 millimeters per year (mm yr−1 distributed as 152 mm yr−1 (58% of surface runoff, 103 mm yr−1 (39% of lateral flow and 8 mm yr−1 (3% of return flow from the aquifer. These results are integrated on a reduced basin area downstream from large dams and are closer to observations than previous modeling exercises.

  5. Modeling mind-wandering: a tool to better understand distraction

    NARCIS (Netherlands)

    van Vugt, Marieke; Taatgen, Niels; Sackur, Jerome; Bastian, Mikael; Taatgen, Niels; van Vugt, Marieke; Borst, Jelmer; Mehlhorn, Katja

    2015-01-01

    When we get distracted, we may engage in mind-wandering, or task-unrelated thinking, which impairs performance on cognitive tasks. Yet, we do not have cognitive models that make this process explicit. On the basis of both recent experiments that have started to investigate mind-wandering and

  6. Understanding the Mechanism of Soil Erosion from Outdoor Model ...

    African Journals Online (AJOL)

    A method for obtaining important data on eroded soils, using a one eight experimental slope model is presented. The scope of the investigation herein described encompassed three locations in the south- eastern parts of Nigeria, which are belts of severe erosion, namely Opi-Nsukka, Agulu and Udi, [Fig. 1.] Soil samples ...

  7. Computer modelling as a tool for understanding language evolution

    NARCIS (Netherlands)

    de Boer, Bart; Gontier, N; VanBendegem, JP; Aerts, D

    2006-01-01

    This paper describes the uses of computer models in studying the evolution of language. Language is a complex dynamic system that can be studied at the level of the individual and at the level of the population. Much of the dynamics of language evolution and language change occur because of the

  8. Model systems for understanding absorption tuning by opsin proteins

    DEFF Research Database (Denmark)

    Nielsen, Mogens Brøndsted

    2009-01-01

    This tutorial review reports on model systems that have been synthesised and investigated for elucidating how opsin proteins tune the absorption of the protonated retinal Schiff base chromophore. In particular, the importance of the counteranion is highlighted. In addition, the review advocates...... is avoided, and it becomes clear that opsin proteins induce blueshifts in the chromophore absorption rather than redshifts....

  9. Understanding ecohydrological connectivity in savannas: A system dynamics modeling approach

    Science.gov (United States)

    Ecohydrological connectivity is a system-level property that results from the linkages in the networks of water transport through ecosystems, by which feedback effects and other emergent system behaviors may be generated. We created a systems dynamic model that represents primary ecohydrological net...

  10. Taenia solium: current understanding of laboratory animal models of taeniosis.

    Science.gov (United States)

    Flisser, A; Avila, G; Maravilla, P; Mendlovic, F; León-Cabrera, S; Cruz-Rivera, M; Garza, A; Gómez, B; Aguilar, L; Terán, N; Velasco, S; Benítez, M; Jimenez-Gonzalez, D E

    2010-03-01

    Neurocysticercosis is a public health problem in many developing countries and is the most frequent parasitic disease of the brain. The human tapeworm carrier is the main risk factor for acquiring neurocysticercosis. Since the parasite lodges only in the human intestine, experimental models of Taenia solium taeniosis have been explored. Macaques, pigs, dogs, cats and rabbits are unsuccessful hosts even in immunodepressed status. By contrast, rodents are adequate hosts since tapeworms with mature, pregravid and, in some cases, gravid proglottids develop after infection. In this review, information that has been generated with experimental models of taeniosis due to T. solium is discussed. Initially, the use of the model for immunodiagnosis of human taeniosis and evaluation of intervention measures is summarized. Next, descriptions of tapeworms and comparison of hamsters, gerbils and other mammals as experimental models are discussed, as well as data on the humoral immune response, the inflammatory reaction and the production of cytokines associated to Th1 and Th2 responses in the intestinal mucosa. Finally, evaluation of protection induced against the development of tapeworms by recombinant T. solium calreticulin in hamsters is summarized and compared to other studies.

  11. Understanding organizational congruence: formal model and simulation framework.

    NARCIS (Netherlands)

    Dignum, M.V.; Dignum, F.P.M.

    2007-01-01

    Despite a large number of studies, the effect of organizational structure on the performance and the individual cognition of its members is still not well understood. Our research aims at developing tools and formalisms to model organizations and evaluate their performance under different

  12. Gnotobiotic mouse model's contribution to understanding host-pathogen interactions

    Czech Academy of Sciences Publication Activity Database

    Kubelková, K.; Benuchová, M.; Kozáková, Hana; Šinkora, Marek; Kročová, Z.; Pejchal, J.; Macela, A.

    2016-01-01

    Roč. 73, č. 20 (2016), s. 3961-3969 ISSN 1420-682X R&D Projects: GA ČR GA15-02274S Institutional support: RVO:61388971 Keywords : Germ- free model * Gnotobiology * Host-pathogen interaction Subject RIV: EC - Immunology Impact factor: 5.788, year: 2016

  13. Towards an understanding of business model innovation processes

    DEFF Research Database (Denmark)

    Taran, Yariv; Boer, Harry; Lindgren, Peter

    2009-01-01

    Companies today, in some industries more than others, invest more capital and resources just to stay competitive, develop more diverse solutions, and increasingly start to think more radically, when considering to innovate their business model. However, the development and innovation of business...

  14. Understanding and quantifying foliar temperature acclimation for Earth System Models

    Science.gov (United States)

    Smith, N. G.; Dukes, J.

    2015-12-01

    Photosynthesis and respiration on land are the two largest carbon fluxes between the atmosphere and Earth's surface. The parameterization of these processes represent major uncertainties in the terrestrial component of the Earth System Models used to project future climate change. Research has shown that much of this uncertainty is due to the parameterization of the temperature responses of leaf photosynthesis and autotrophic respiration, which are typically based on short-term empirical responses. Here, we show that including longer-term responses to temperature, such as temperature acclimation, can help to reduce this uncertainty and improve model performance, leading to drastic changes in future land-atmosphere carbon feedbacks across multiple models. However, these acclimation formulations have many flaws, including an underrepresentation of many important global flora. In addition, these parameterizations were done using multiple studies that employed differing methodology. As such, we used a consistent methodology to quantify the short- and long-term temperature responses of maximum Rubisco carboxylation (Vcmax), maximum rate of Ribulos-1,5-bisphosphate regeneration (Jmax), and dark respiration (Rd) in multiple species representing each of the plant functional types used in global-scale land surface models. Short-term temperature responses of each process were measured in individuals acclimated for 7 days at one of 5 temperatures (15-35°C). The comparison of short-term curves in plants acclimated to different temperatures were used to evaluate long-term responses. Our analyses indicated that the instantaneous response of each parameter was highly sensitive to the temperature at which they were acclimated. However, we found that this sensitivity was larger in species whose leaves typically experience a greater range of temperatures over the course of their lifespan. These data indicate that models using previous acclimation formulations are likely incorrectly

  15. MO-E-18C-04: Advanced Computer Simulation and Visualization Tools for Enhanced Understanding of Core Medical Physics Concepts

    International Nuclear Information System (INIS)

    Naqvi, S

    2014-01-01

    Purpose: Most medical physics programs emphasize proficiency in routine clinical calculations and QA. The formulaic aspect of these calculations and prescriptive nature of measurement protocols obviate the need to frequently apply basic physical principles, which, therefore, gradually decay away from memory. E.g. few students appreciate the role of electron transport in photon dose, making it difficult to understand key concepts such as dose buildup, electronic disequilibrium effects and Bragg-Gray theory. These conceptual deficiencies manifest when the physicist encounters a new system, requiring knowledge beyond routine activities. Methods: Two interactive computer simulation tools are developed to facilitate deeper learning of physical principles. One is a Monte Carlo code written with a strong educational aspect. The code can “label” regions and interactions to highlight specific aspects of the physics, e.g., certain regions can be designated as “starters” or “crossers,” and any interaction type can be turned on and off. Full 3D tracks with specific portions highlighted further enhance the visualization of radiation transport problems. The second code calculates and displays trajectories of a collection electrons under arbitrary space/time dependent Lorentz force using relativistic kinematics. Results: Using the Monte Carlo code, the student can interactively study photon and electron transport through visualization of dose components, particle tracks, and interaction types. The code can, for instance, be used to study kerma-dose relationship, explore electronic disequilibrium near interfaces, or visualize kernels by using interaction forcing. The electromagnetic simulator enables the student to explore accelerating mechanisms and particle optics in devices such as cyclotrons and linacs. Conclusion: The proposed tools are designed to enhance understanding of abstract concepts by highlighting various aspects of the physics. The simulations serve as

  16. MO-E-18C-04: Advanced Computer Simulation and Visualization Tools for Enhanced Understanding of Core Medical Physics Concepts

    Energy Technology Data Exchange (ETDEWEB)

    Naqvi, S [Saint Agnes Cancer Institute, Department of Radiation Oncology, Baltimore, MD (United States)

    2014-06-15

    Purpose: Most medical physics programs emphasize proficiency in routine clinical calculations and QA. The formulaic aspect of these calculations and prescriptive nature of measurement protocols obviate the need to frequently apply basic physical principles, which, therefore, gradually decay away from memory. E.g. few students appreciate the role of electron transport in photon dose, making it difficult to understand key concepts such as dose buildup, electronic disequilibrium effects and Bragg-Gray theory. These conceptual deficiencies manifest when the physicist encounters a new system, requiring knowledge beyond routine activities. Methods: Two interactive computer simulation tools are developed to facilitate deeper learning of physical principles. One is a Monte Carlo code written with a strong educational aspect. The code can “label” regions and interactions to highlight specific aspects of the physics, e.g., certain regions can be designated as “starters” or “crossers,” and any interaction type can be turned on and off. Full 3D tracks with specific portions highlighted further enhance the visualization of radiation transport problems. The second code calculates and displays trajectories of a collection electrons under arbitrary space/time dependent Lorentz force using relativistic kinematics. Results: Using the Monte Carlo code, the student can interactively study photon and electron transport through visualization of dose components, particle tracks, and interaction types. The code can, for instance, be used to study kerma-dose relationship, explore electronic disequilibrium near interfaces, or visualize kernels by using interaction forcing. The electromagnetic simulator enables the student to explore accelerating mechanisms and particle optics in devices such as cyclotrons and linacs. Conclusion: The proposed tools are designed to enhance understanding of abstract concepts by highlighting various aspects of the physics. The simulations serve as

  17. Modeling Dynamic Food Choice Processes to Understand Dietary Intervention Effects.

    Science.gov (United States)

    Marcum, Christopher Steven; Goldring, Megan R; McBride, Colleen M; Persky, Susan

    2018-02-17

    Meal construction is largely governed by nonconscious and habit-based processes that can be represented as a collection of in dividual, micro-level food choices that eventually give rise to a final plate. Despite this, dietary behavior intervention research rarely captures these micro-level food choice processes, instead measuring outcomes at aggregated levels. This is due in part to a dearth of analytic techniques to model these dynamic time-series events. The current article addresses this limitation by applying a generalization of the relational event framework to model micro-level food choice behavior following an educational intervention. Relational event modeling was used to model the food choices that 221 mothers made for their child following receipt of an information-based intervention. Participants were randomized to receive either (a) control information; (b) childhood obesity risk information; (c) childhood obesity risk information plus a personalized family history-based risk estimate for their child. Participants then made food choices for their child in a virtual reality-based food buffet simulation. Micro-level aspects of the built environment, such as the ordering of each food in the buffet, were influential. Other dynamic processes such as choice inertia also influenced food selection. Among participants receiving the strongest intervention condition, choice inertia decreased and the overall rate of food selection increased. Modeling food selection processes can elucidate the points at which interventions exert their influence. Researchers can leverage these findings to gain insight into nonconscious and uncontrollable aspects of food selection that influence dietary outcomes, which can ultimately improve the design of dietary interventions.

  18. Fixed-site physical protection system modeling

    International Nuclear Information System (INIS)

    Chapman, L.D.

    1975-01-01

    An evaluation of a fixed-site safeguard security system must consider the interrelationships of barriers, alarms, on-site and off-site guards, and their effectiveness against a forcible adversary attack whose intention is to create an act of sabotage or theft. A computer model has been developed at Sandia Laboratories for the evaluation of alternative fixed-site security systems. Trade-offs involving on-site and off-site response forces and response times, perimeter alarm systems, barrier configurations, and varying levels of threat can be analyzed. The computer model provides a framework for performing inexpensive experiments on fixed-site security systems for testing alternative decisions, and for determining the relative cost effectiveness associated with these decision policies

  19. A modeling process to understand complex system architectures

    Science.gov (United States)

    Robinson, Santiago Balestrini

    2009-12-01

    In recent decades, several tools have been developed by the armed forces, and their contractors, to test the capability of a force. These campaign level analysis tools, often times characterized as constructive simulations are generally expensive to create and execute, and at best they are extremely difficult to verify and validate. This central observation, that the analysts are relying more and more on constructive simulations to predict the performance of future networks of systems, leads to the two central objectives of this thesis: (1) to enable the quantitative comparison of architectures in terms of their ability to satisfy a capability without resorting to constructive simulations, and (2) when constructive simulations must be created, to quantitatively determine how to spend the modeling effort amongst the different system classes. The first objective led to Hypothesis A, the first main hypotheses, which states that by studying the relationships between the entities that compose an architecture, one can infer how well it will perform a given capability. The method used to test the hypothesis is based on two assumptions: (1) the capability can be defined as a cycle of functions, and that it (2) must be possible to estimate the probability that a function-based relationship occurs between any two types of entities. If these two requirements are met, then by creating random functional networks, different architectures can be compared in terms of their ability to satisfy a capability. In order to test this hypothesis, a novel process for creating representative functional networks of large-scale system architectures was developed. The process, named the Digraph Modeling for Architectures (DiMA), was tested by comparing its results to those of complex constructive simulations. Results indicate that if the inputs assigned to DiMA are correct (in the tests they were based on time-averaged data obtained from the ABM), DiMA is able to identify which of any two

  20. Enhancing Laos Students' Understanding of Nature of Science in Physics Learning about Atom for Peace

    Science.gov (United States)

    Sengdala, Phoxay; Yuenyong, Chokchai

    2014-01-01

    This paper aimed to study of Grade 12 students' understanding of nature of science in learning about atom for peace through science technology and society (STS) approach. Participants were 51 Grade 12 who study in Thongphong high school Vientiane Capital City Lao PDR, 1st semester of 2012 academic year. This research regarded interpretive…