WorldWideScience

Sample records for greatest difficulty posed

  1. Will Climate Change, Genetic and Demographic Variation or Rat Predation Pose the Greatest Risk for Persistence of an Altitudinally Distributed Island Endemic?

    Directory of Open Access Journals (Sweden)

    Alison Shapcott

    2012-11-01

    Full Text Available Species endemic to mountains on oceanic islands are subject to a number of existing threats (in particular, invasive species along with the impacts of a rapidly changing climate. The Lord Howe Island endemic palm Hedyscepe canterburyana is restricted to two mountains above 300 m altitude. Predation by the introduced Black Rat (Rattus rattus is known to significantly reduce seedling recruitment. We examined the variation in Hedyscepe in terms of genetic variation, morphology, reproductive output and demographic structure, across an altitudinal gradient. We used demographic data to model population persistence under climate change predictions of upward range contraction incorporating long-term climatic records for Lord Howe Island. We also accounted for alternative levels of rat predation into the model to reflect management options for control. We found that Lord Howe Island is getting warmer and drier and quantified the degree of temperature change with altitude (0.9 °C per 100 m. For H. canterburyana, differences in development rates, population structure, reproductive output and population growth rate were identified between altitudes. In contrast, genetic variation was high and did not vary with altitude. There is no evidence of an upward range contraction as was predicted and recruitment was greatest at lower altitudes. Our models predicted slow population decline in the species and that the highest altitude populations are under greatest threat of extinction. Removal of rat predation would significantly enhance future persistence of this species.

  2. Which US States Pose the Greatest Threats to Military Readiness and Public Health? Public Health Policy Implications for a Cross-sectional Investigation of Cardiorespiratory Fitness, Body Mass Index, and Injuries Among US Army Recruits.

    Science.gov (United States)

    Bornstein, Daniel B; Grieve, George L; Clennin, Morgan N; McLain, Alexander C; Whitsel, Laurie P; Beets, Michael W; Hauret, Keith G; Jones, Bruce H; Sarzynski, Mark A

    2018-01-09

    Many states in the southern region of the United States are recognized for higher rates of obesity, physical inactivity, and chronic disease. These states are therefore recognized for their disproportionate public health burden. The purpose of this study was to investigate state-level distributions of cardiorespiratory fitness, body mass index (BMI), and injuries among US Army recruits in order to determine whether or not certain states may also pose disproportionate threats to military readiness and national security. Sex-specific state-level values for injuries and fitness among 165 584 Army recruits were determined. Next, the relationship between median cardiorespiratory fitness and injury incidence at the state level was examined using Spearman correlations. Finally, multivariable Poisson regression models stratified by sex examined state-level associations between fitness and injury incidence, while controlling for BMI, and other covariates. Cardiorespiratory fitness and training-related injury incidence. A cluster of 10 states from the south and southeastern regions (Alabama, Arkansas, Florida, Georgia, Louisiana, Mississippi, North Carolina, South Carolina, Tennessee, and Texas) produced male or female recruits who were significantly less fit and/or more likely to become injured than recruits from other US states. Compared with the "most fit states," the incidence of injuries increased by 22% (95% CI, 17-28; P < .001) and 28% (95% CI, 19-36; P < .001) in male and female recruits from the "least fit states," respectively. The impact of policies, systems, and environments on physical activity behavior, and subsequently fitness and health, has been clearly established. Advocacy efforts aimed at active living policies, systems, and environmental changes to improve population health often fail. However, advocating for active living policies to improve national security may prove more promising, particularly with legislators. Results from this study demonstrate

  3. The Greatest Mathematical Discovery?

    Energy Technology Data Exchange (ETDEWEB)

    Bailey, David H.; Borwein, Jonathan M.

    2010-05-12

    What mathematical discovery more than 1500 years ago: (1) Is one of the greatest, if not the greatest, single discovery in the field of mathematics? (2) Involved three subtle ideas that eluded the greatest minds of antiquity, even geniuses such as Archimedes? (3) Was fiercely resisted in Europe for hundreds of years after its discovery? (4) Even today, in historical treatments of mathematics, is often dismissed with scant mention, or else is ascribed to the wrong source? Answer: Our modern system of positional decimal notation with zero, together with the basic arithmetic computational schemes, which were discovered in India about 500 CE.

  4. Nature's Greatest Puzzles

    International Nuclear Information System (INIS)

    Quigg, Chris

    2005-01-01

    It is a pleasure to be part of the SLAC Summer Institute again, not simply because it is one of the great traditions in our field, but because this is a moment of great promise for particle physics. I look forward to exploring many opportunities with you over the course of our two weeks together. My first task in talking about Nature's Greatest Puzzles, the title of this year's Summer Institute, is to deconstruct the premise a little bit

  5. Computational Physics' Greatest Hits

    Science.gov (United States)

    Bug, Amy

    2011-03-01

    The digital computer, has worked its way so effectively into our profession that now, roughly 65 years after its invention, it is virtually impossible to find a field of experimental or theoretical physics unaided by computational innovation. It is tough to think of another device about which one can make that claim. In the session ``What is computational physics?'' speakers will distinguish computation within the field of computational physics from this ubiquitous importance across all subfields of physics. This talk will recap the invited session ``Great Advances...Past, Present and Future'' in which five dramatic areas of discovery (five of our ``greatest hits'') are chronicled: The physics of many-boson systems via Path Integral Monte Carlo, the thermodynamic behavior of a huge number of diverse systems via Monte Carlo Methods, the discovery of new pharmaceutical agents via molecular dynamics, predictive simulations of global climate change via detailed, cross-disciplinary earth system models, and an understanding of the formation of the first structures in our universe via galaxy formation simulations. The talk will also identify ``greatest hits'' in our field from the teaching and research perspectives of other members of DCOMP, including its Executive Committee.

  6. Problem Posing

    OpenAIRE

    Šilhavá, Marie

    2009-01-01

    This diploma thesis concentrates on problem posing from the students' point of view. Problem posing can be either seen as a teaching method which can be used in the class, or it can be used as a tool for researchers or teachers to assess the level of students' understanding of the topic. In my research, I compare three classes, one mathematics specialist class and two generalist classes, in their ability of problem posing. As an assessment tool it seemed that mathemathics specialists were abl...

  7. Nature's Greatest Puzzles

    Energy Technology Data Exchange (ETDEWEB)

    Quigg, Chris; /Fermilab

    2005-02-01

    It is a pleasure to be part of the SLAC Summer Institute again, not simply because it is one of the great traditions in our field, but because this is a moment of great promise for particle physics. I look forward to exploring many opportunities with you over the course of our two weeks together. My first task in talking about Nature's Greatest Puzzles, the title of this year's Summer Institute, is to deconstruct the premise a little bit.

  8. Pose Space Surface Manipulation

    Directory of Open Access Journals (Sweden)

    Yusuke Yoshiyasu

    2012-01-01

    Full Text Available Example-based mesh deformation techniques produce natural and realistic shapes by learning the space of deformations from examples. However, skeleton-based methods cannot manipulate a global mesh structure naturally, whereas the mesh-based approaches based on a translational control do not allow the user to edit a local mesh structure intuitively. This paper presents an example-driven mesh editing framework that achieves both global and local pose manipulations. The proposed system is built with a surface deformation method based on a two-step linear optimization technique and achieves direct manipulations of a model surface using translational and rotational controls. With the translational control, the user can create a model in natural poses easily. The rotational control can adjust the local pose intuitively by bending and twisting. We encode example deformations with a rotation-invariant mesh representation which handles large rotations in examples. To incorporate example deformations, we infer a pose from the handle translations/rotations and perform pose space interpolation, thereby avoiding involved nonlinear optimization. With the two-step linear approach combined with the proposed multiresolution deformation method, we can edit models at interactive rates without losing important deformation effects such as muscle bulging.

  9. Pose and Solve Varignon Converse Problems

    Science.gov (United States)

    Contreras, José N.

    2014-01-01

    The activity of posing and solving problems can enrich learners' mathematical experiences because it fosters a spirit of inquisitiveness, cultivates their mathematical curiosity, and deepens their views of what it means to do mathematics. To achieve these goals, a mathematical problem needs to be at the appropriate level of difficulty,…

  10. The Greatest Challenge Ever for Mankind, Requiring Policies of Accelerating Hardship and Implementation Difficulty

    Science.gov (United States)

    Wilson, John

    2015-04-01

    Providing energy for the contemporary world has resulted in a multi-variable problem in which a confluence of historical anomalies and economic, psychological, political, and demographic factors thwart efforts to prevent significant harm from increasing atmospheric CO2. This unlikely combination has created the perfect storm in which the warnings by scientists are ineffective. Global warming is occurring simultaneously with increased population, some dysfunctional political institutions, ascendency of oversimplified economic theory, campaigns to discredit scientists, misinterpretation of the meaning of noise in the Milankovitch climate cycles, and substantially improved hydrocarbon extraction methods. These factors are compounded by traits of human nature, such as greed and resistance to changing the familiar and discontinuing profitable endeavors. The idea that future people are equal with us may not be widely supported, yet this value is the foundation of climate change action. History shows that most people and nations will not take appropriate measures until forced, yet the cost increases as action is delayed. This makes appropriate policies even more extreme and difficult to accomplish as more wealth is consumed in treating global warming symptoms.

  11. Meanings Given to Algebraic Symbolism in Problem-Posing

    Science.gov (United States)

    Cañadas, María C.; Molina, Marta; del Río, Aurora

    2018-01-01

    Some errors in the learning of algebra suggest that students might have difficulties giving meaning to algebraic symbolism. In this paper, we use problem posing to analyze the students' capacity to assign meaning to algebraic symbolism and the difficulties that students encounter in this process, depending on the characteristics of the algebraic…

  12. Boneless Pose Editing and Animation

    DEFF Research Database (Denmark)

    Bærentzen, Jakob Andreas; Hansen, Kristian Evers; Erleben, Kenny

    2007-01-01

    In this paper, we propose a pose editing and animation method for triangulated surfaces based on a user controlled partitioning of the model into deformable parts and rigid parts which are denoted handles. In our pose editing system, the user can sculpt a set of poses simply by transforming...... the handles for each pose. Using Laplacian editing, the deformable parts are deformed to match the handles. In our animation system the user can constrain one or several handles in order to define a new pose. New poses are interpolated from the examples poses, by solving a small non-linear optimization...... problem in order to obtain the interpolation weights. While the system can be used simply for building poses, it is also an animation system. The user can specify a path for a given constraint and the model is animated correspondingly....

  13. The art of problem posing

    CERN Document Server

    Brown, Stephen I

    1990-01-01

    Updated and expanded, this second edition satisfies the same philosophical objective as the first -- to show the importance of problem posing. Although interest in mathematical problem solving increased during the past decade, problem posing remained relatively ignored. The Art of Problem Posing draws attention to this equally important act and is the innovator in the field. Special features include: * an exploration ofthe logical relationship between problem posing and problem solving * a special chapter devoted to teaching problem posing as a separate course * sketches, drawings, diagrams, and cartoons that illustrate the schemes proposed * a special section on writing in mathematics.

  14. Problem posing reflections and applications

    CERN Document Server

    Brown, Stephen I

    2014-01-01

    As a result of the editors' collaborative teaching at Harvard in the late 1960s, they produced a ground-breaking work -- The Art Of Problem Posing -- which related problem posing strategies to the already popular activity of problem solving. It took the concept of problem posing and created strategies for engaging in that activity as a central theme in mathematics education. Based in part upon that work and also upon a number of articles by its authors, other members of the mathematics education community began to apply and expand upon their ideas. This collection of thirty readings is a tes

  15. A Fruitful Activity for Finding the Greatest Common Factor

    Science.gov (United States)

    Bell, Carol J.; Leisner, Heather J.; Shelley, Kristina

    2011-01-01

    Posing mathematics problems in different ways will raise students' level of cognitive demand because it will push them to think more deeply about mathematics. By engaging students in a task that requires them to determine their own solution strategies, students will gain a deeper understanding of the mathematical concept explored through the task.…

  16. Is supergravity well-posed?

    International Nuclear Information System (INIS)

    Isenberg, J.; Bao, D.; Yasskin, P.B.

    1983-01-01

    One rather fundamental question concerning supergravity remains unresolved: Is supergravity a well-posed field theory? That is, does a set of certain (Cauchy) data specified on some initial spacelike surface determine a unique, causally propagating spacetime solution of the supergravity field equations (at least in some finite neighborhood of the initial surface)? In this paper, the authors give a very brief report on work directed towards answering this question. (Auth.)

  17. Was ocean acidification responsible for history's greatest extinction?

    Science.gov (United States)

    Schultz, Colin

    2011-11-01

    Two hundred fifty million years ago, the world suffered the greatest recorded extinction of all time. More than 90% of marine animals and a majority of terrestrial species disappeared, yet the cause of the Permian-Triassic boundary (PTB) dieoff remains unknown. Various theories abound, with most focusing on rampant Siberian volcanism and its potential consequences: global warming, carbon dioxide poisoning, ocean acidification, or the severe drawdown of oceanic dissolved oxygen levels, also known as anoxia. To narrow the range of possible causes, Montenegro et al. ran climate simulations for PTB using the University of Victoria Earth System Climate Model, a carbon cycle-climate coupled general circulation model.

  18. Massive the Higgs boson and the greatest hunt in science

    CERN Document Server

    Sample, Ian

    2013-01-01

    Now fully updated -- this is the dramatic and gripping account of the greatest scientific discovery of our time. In the early 1960s, three groups of physicists, working independently in different countries, stumbled upon an idea that would change physics and fuel the imagination of scientists for decades. That idea was the Higgs boson -- to find it would be to finally understand the origins of mass -- the last building block of life itself. Now, almost 50 years later, that particle has finally been discovered.

  19. Penicillin: the medicine with the greatest impact on therapeutic outcomes.

    Science.gov (United States)

    Kardos, Nelson; Demain, Arnold L

    2011-11-01

    The principal point of this paper is that the discovery of penicillin and the development of the supporting technologies in microbiology and chemical engineering leading to its commercial scale production represent it as the medicine with the greatest impact on therapeutic outcomes. Our nomination of penicillin for the top therapeutic molecule rests on two lines of evidence concerning the impact of this event: (1) the magnitude of the therapeutic outcomes resulting from the clinical application of penicillin and the subsequent widespread use of antibiotics and (2) the technologies developed for production of penicillin, including both microbial strain selection and improvement plus chemical engineering methods responsible for successful submerged fermentation production. These became the basis for production of all subsequent antibiotics in use today. These same technologies became the model for the development and production of new types of bioproducts (i.e., anticancer agents, monoclonal antibodies, and industrial enzymes). The clinical impact of penicillin was large and immediate. By ushering in the widespread clinical use of antibiotics, penicillin was responsible for enabling the control of many infectious diseases that had previously burdened mankind, with subsequent impact on global population demographics. Moreover, the large cumulative public effect of the many new antibiotics and new bioproducts that were developed and commercialized on the basis of the science and technology after penicillin demonstrates that penicillin had the greatest therapeutic impact event of all times. © Springer-Verlag 2011

  20. Greatest Happiness Principle in a Complex System Approach

    Directory of Open Access Journals (Sweden)

    Katalin Martinás

    2012-06-01

    Full Text Available The principle of greatest happiness was the basis of ethics in Plato’s and Aristotle’s work, it served as the basis of utility principle in economics, and the happiness research has become a hot topic in social sciences in Western countries in particular in economics recently. Nevertheless there is a considerable scientific pessimism over whether it is even possible to affect sustainable increases in happiness.In this paper we outline an economic theory of decision based on the greatest happiness principle (GHP. Modern equilibrium economics is a simple system simplification of the GHP, the complex approach outlines a non-equilibrium economic theory. The comparison of the approaches reveals the fact that the part of the results – laws of modern economics – follow from the simplifications and they are against the economic nature. The most important consequence is that within the free market economy one cannot be sure that the path found by it leads to a beneficial economic system.

  1. Masses of galaxies and the greatest redshifts of quasars

    Energy Technology Data Exchange (ETDEWEB)

    Hills, J G [Illinois Univ., Urbana (USA)

    1977-04-01

    The outer parts of a typical galaxy follows an R/sup -2/ density distribution which results in the collapse time of its protogalaxy being proportional to its mass. Since quasars probably occur in the nuclei of galaxies which can only form after the collapse of their parent galaxies, their greatest observed redshift, Zsub(max), is largely determined by the mass, Msub(t), of a typical protogalaxy. The observed Zsub(max) of quasars indicates that Msub(t) = 1 x 10/sup 12/ solar masses. This mass is consistent with the masses of galaxies found in recent dynamical studies. It indicates that most of the mass in a typical galaxy is in the halo lying beyond the familiar optically-bright core, but the mass of a standard galaxy is still only 0.3 of that required for galaxies alone to close the universe.

  2. Statistical Model-Based Face Pose Estimation

    Institute of Scientific and Technical Information of China (English)

    GE Xinliang; YANG Jie; LI Feng; WANG Huahua

    2007-01-01

    A robust face pose estimation approach is proposed by using face shape statistical model approach and pose parameters are represented by trigonometric functions. The face shape statistical model is firstly built by analyzing the face shapes from different people under varying poses. The shape alignment is vital in the process of building the statistical model. Then, six trigonometric functions are employed to represent the face pose parameters. Lastly, the mapping function is constructed between face image and face pose by linearly relating different parameters. The proposed approach is able to estimate different face poses using a few face training samples. Experimental results are provided to demonstrate its efficiency and accuracy.

  3. EPR by Areva. The path of greatest certainty

    International Nuclear Information System (INIS)

    2008-01-01

    earliest design stages, the EPR has been designed to comply with the most stringent safety requirements: Airplane crash resistance, Accident consequences limited by an optimal combination of passive and active safety systems, Core melt catcher, Quadruple redundancy with independent trains for each safeguard system, Even lower probability of core damage, Double containment shell. Its evolutionary advances are proven, leaving none of the question marks posed by 'revolutionary' designs. On the contrary, the EPR evolutionary design protects utilities' corporate responsibility. The EPR has been designed to minimize its impact on the environment while achieving its operational objectives: Maximum power output per site, Lower natural Uranium consumption per MWh, Reduced long-lived high-level waste generation during operation, Capability to use MOX (Mixed Oxide) and reprocessed uranium fuel, Minimal quantities of high activity metal structure, Less water usage thanks to improved thermal efficiency, Minimum impact on health. Thanks to its low fuel consumption, maintenance and operating costs, the EPR is a perfect choice for utilities: Lower total fuel costs, Lower operation and maintenance costs, Higher power output per site, Savings accruing from the experience feedback of a global EPR fleet and associated owners' Group, High plant efficiency

  4. EPR by Areva. The path of greatest certainty

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2008-07-01

    integrated and mastered by AREVA. From its earliest design stages, the EPR has been designed to comply with the most stringent safety requirements: Airplane crash resistance, Accident consequences limited by an optimal combination of passive and active safety systems, Core melt catcher, Quadruple redundancy with independent trains for each safeguard system, Even lower probability of core damage, Double containment shell. Its evolutionary advances are proven, leaving none of the question marks posed by 'revolutionary' designs. On the contrary, the EPR evolutionary design protects utilities' corporate responsibility. The EPR has been designed to minimize its impact on the environment while achieving its operational objectives: Maximum power output per site, Lower natural Uranium consumption per MWh, Reduced long-lived high-level waste generation during operation, Capability to use MOX (Mixed Oxide) and reprocessed uranium fuel, Minimal quantities of high activity metal structure, Less water usage thanks to improved thermal efficiency, Minimum impact on health. Thanks to its low fuel consumption, maintenance and operating costs, the EPR is a perfect choice for utilities: Lower total fuel costs, Lower operation and maintenance costs, Higher power output per site, Savings accruing from the experience feedback of a global EPR fleet and associated owners' Group, High plant efficiency.

  5. Problem Posing with Realistic Mathematics Education Approach in Geometry Learning

    Science.gov (United States)

    Mahendra, R.; Slamet, I.; Budiyono

    2017-09-01

    One of the difficulties of students in the learning of geometry is on the subject of plane that requires students to understand the abstract matter. The aim of this research is to determine the effect of Problem Posing learning model with Realistic Mathematics Education Approach in geometry learning. This quasi experimental research was conducted in one of the junior high schools in Karanganyar, Indonesia. The sample was taken using stratified cluster random sampling technique. The results of this research indicate that the model of Problem Posing learning with Realistic Mathematics Education Approach can improve students’ conceptual understanding significantly in geometry learning especially on plane topics. It is because students on the application of Problem Posing with Realistic Mathematics Education Approach are become to be active in constructing their knowledge, proposing, and problem solving in realistic, so it easier for students to understand concepts and solve the problems. Therefore, the model of Problem Posing learning with Realistic Mathematics Education Approach is appropriately applied in mathematics learning especially on geometry material. Furthermore, the impact can improve student achievement.

  6. Pengenalan Pose Tangan Menggunakan HuMoment

    Directory of Open Access Journals (Sweden)

    Dina Budhi Utami

    2017-02-01

    Full Text Available Computer vision yang didasarkan pada pengenalan bentuk memiliki banyak potensi dalam interaksi manusia dan komputer. Pose tangan dapat dijadikan simbol interaksi manusia dengan komputer seperti halnya pada penggunaan berbagai pose tangan pada bahasa isyarat. Berbagai pose tangan dapat digunakan untuk menggantikan fungsi mouse, untuk mengendalikan robot, dan sebagainya. Penelitian ini difokuskan pada pembangunan sistem pengenalan pose tangan menggunakan HuMoment. Proses pengenalan pose tangan dimulai dengan melakukan segmentasi citra masukan untuk menghasilkan citra ROI (Region of Interest yaitu area telapak tangan. Selanjutnya dilakukan proses deteksi tepi. Kemudian dilakukan ekstraksi nilai HuMoment. Nilai HuMoment dikuantisasikan ke dalam bukukode yang dihasilkan dari proses pelatihan menggunakan K-Means. Proses kuantisasi dilakukan dengan menghitung nilai Euclidean Distance terkecil antara nilai HuMomment citra masukan dan bukukode. Berdasarkan hasil penelitian, nilai akurasi sistem dalam mengenali pose tangan adalah 88.57%.

  7. How Do Environmental Issues Contribute to Regional Instability? and Which Regions Will Pose the Greatest Threat to U.S. Security as a Result of Environmental Degredation?

    National Research Council Canada - National Science Library

    Schantz, Blair

    1998-01-01

    .... The primary objective of this research is to determine and define how environmental issues contribute to regional political, economic or physical instability and then apply this definition to the regions of the world...

  8. Residents in difficulty

    DEFF Research Database (Denmark)

    Christensen, Mette Krogh; O'Neill, Lotte; Hansen, Dorthe Høgh

    2016-01-01

    Background The majority of studies on prevalence and characteristics of residents in difficulty have been conducted in English-speaking countries and the existing literature may not reflect the prevalence and characteristics of residents in difficulty in other parts of the world such as the Scand...... in a healthcare system. From our perspective, further sociological and pedagogical investigations in educational cultures across settings and specialties could inform our understanding of and knowledge about pitfalls in residents’ and doctors’ socialization into the healthcare system....

  9. Manifolds for pose tracking from monocular video

    Science.gov (United States)

    Basu, Saurav; Poulin, Joshua; Acton, Scott T.

    2015-03-01

    We formulate a simple human-pose tracking theory from monocular video based on the fundamental relationship between changes in pose and image motion vectors. We investigate the natural embedding of the low-dimensional body pose space into a high-dimensional space of body configurations that behaves locally in a linear manner. The embedded manifold facilitates the decomposition of the image motion vectors into basis motion vector fields of the tangent space to the manifold. This approach benefits from the style invariance of image motion flow vectors, and experiments to validate the fundamental theory show reasonable accuracy (within 4.9 deg of the ground truth).

  10. Energy taxation difficulties

    International Nuclear Information System (INIS)

    Landsberg, H.H.

    1993-01-01

    This paper assesses what may be the underlying reasons for the Clinton administration's recent failure to pass the Btu Tax on energy sources and the current difficulties that this Administration is experiencing in acquiring nation wide consensus on a gasoline tax proposal. Two difficulties stand out - regional differences in climate and thus winter heating requirements, and the differences from state to state in transportation system preferences. The paper cites the positive aspects of energy taxation by noting the petroleum industry's efforts to develop a new less polluting reformulated gasoline

  11. Students’ Creativity: Problem Posing in Structured Situation

    Science.gov (United States)

    Amalina, I. K.; Amirudin, M.; Budiarto, M. T.

    2018-01-01

    This is a qualitative research concerning on students’ creativity on problem posing task. The study aimed at describing the students’ creative thinking ability to pose the mathematics problem in structured situations with varied condition of given problems. In order to find out the students’ creative thinking ability, an analysis of mathematics problem posing test based on fluency, novelty, and flexibility and interview was applied for categorizing students’ responses on that task. The data analysis used the quality of problem posing and categorized in 4 level of creativity. The results revealed from 29 secondary students grade 8, a student in CTL (Creative Thinking Level) 1 met the fluency. A student in CTL 2 met the novelty, while a student in CTL 3 met both fluency and novelty and no one in CTL 4. These results are affected by students’ mathematical experience. The findings of this study highlight that student’s problem posing creativity are dependent on their experience in mathematics learning and from the point of view of which students start to pose problem.

  12. Difficulty scaling through incongruity

    NARCIS (Netherlands)

    Lankveld, van G.; Spronck, P.; Rauterberg, G.W.M.; Mateas, M.; Darken, C.

    2008-01-01

    In this paper we discuss our work on using the incongruity measure from psychological literature to scale the difficulty level of a game online to the capabilities of the human player. Our approach has been implemented in a small game called Glove.

  13. Breathing difficulty - lying down

    Science.gov (United States)

    ... other conditions that lead to it) Panic disorder Sleep apnea Snoring Home Care Your health care provider may recommend self-care measures. For example, weight loss may be suggested if you are obese. When to Contact a Medical Professional If you have any unexplained difficulty in breathing ...

  14. Veganism: Motivations and Difficulties

    OpenAIRE

    Beck, Mathilde Therese Claudine; Harvey, John Carr; Trauth, Christina

    2017-01-01

    An increasing number of people are adopting a vegan lifestyle, which means to stop consuming products, that are made from or based on animals, like meat, dairy or eggs. However, the number of research concerning veganism is limited. As the existing research is mainly concentrating on the process of adopting a vegan lifestyle and the view of vegans, these findings shall be examined further with the question, What are the motivation and difficulties about adopting a plant based vegan diet in We...

  15. Idiopathic chondrolysis - diagnostic difficulties

    International Nuclear Information System (INIS)

    Kozlowski, K.; Scougall, J.; Royal Alexandra Hospital for Children, Sydney

    1984-01-01

    Four cases of idiopathic chondrolysis of the hip in three white girls and one Maori girl are reported. The authors stress the causes why a disease with characteristic clinical and radiographic appearances and normal biochemical findings presents diagnostic difficulties. It is suspected that idiopathic chondrolysis is a metabolic disorder of chondrocytes, triggered by environment circumstances in susceptible individuals. Idiopathic chondrolysis is probably one of the most common causes of coxarthrosis in women. (orig.)

  16. Exemplar-based human action pose correction.

    Science.gov (United States)

    Shen, Wei; Deng, Ke; Bai, Xiang; Leyvand, Tommer; Guo, Baining; Tu, Zhuowen

    2014-07-01

    The launch of Xbox Kinect has built a very successful computer vision product and made a big impact on the gaming industry. This sheds lights onto a wide variety of potential applications related to action recognition. The accurate estimation of human poses from the depth image is universally a critical step. However, existing pose estimation systems exhibit failures when facing severe occlusion. In this paper, we propose an exemplar-based method to learn to correct the initially estimated poses. We learn an inhomogeneous systematic bias by leveraging the exemplar information within a specific human action domain. Furthermore, as an extension, we learn a conditional model by incorporation of pose tags to further increase the accuracy of pose correction. In the experiments, significant improvements on both joint-based skeleton correction and tag prediction are observed over the contemporary approaches, including what is delivered by the current Kinect system. Our experiments for the facial landmark correction also illustrate that our algorithm can improve the accuracy of other detection/estimation systems.

  17. An improved silhouette for human pose estimation

    Science.gov (United States)

    Hawes, Anthony H.; Iftekharuddin, Khan M.

    2017-08-01

    We propose a novel method for analyzing images that exploits the natural lines of a human poses to find areas where self-occlusion could be present. Errors caused by self-occlusion cause several modern human pose estimation methods to mis-identify body parts, which reduces the performance of most action recognition algorithms. Our method is motivated by the observation that, in several cases, occlusion can be reasoned using only boundary lines of limbs. An intelligent edge detection algorithm based on the above principle could be used to augment the silhouette with information useful for pose estimation algorithms and push forward progress on occlusion handling for human action recognition. The algorithm described is applicable to computer vision scenarios involving 2D images and (appropriated flattened) 3D images.

  18. Yoga Poses Increase Subjective Energy and State Self-Esteem in Comparison to 'Power Poses'.

    Science.gov (United States)

    Golec de Zavala, Agnieszka; Lantos, Dorottya; Bowden, Deborah

    2017-01-01

    Research on beneficial consequences of yoga focuses on the effects of yogic breathing and meditation. Less is known about the psychological effects of performing yoga postures. The present study investigated the effects of yoga poses on subjective sense of energy and self-esteem. The effects of yoga postures were compared to the effects of 'power poses,' which arguably increase the sense of power and self-confidence due to their association with interpersonal dominance (Carney et al., 2010). The study tested the novel prediction that yoga poses, which are not associated with interpersonal dominance but increase bodily energy, would increase the subjective feeling of energy and therefore increase self-esteem compared to 'high power' and 'low power' poses. A two factorial, between participants design was employed. Participants performed either two standing yoga poses with open front of the body ( n = 19), two standing yoga poses with covered front of the body ( n = 22), two expansive, high power poses ( n = 21), or two constrictive, low power poses ( n = 20) for 1-min each. The results showed that yoga poses in comparison to 'power poses' increased self-esteem. This effect was mediated by an increased subjective sense of energy and was observed when baseline trait self-esteem was controlled for. These results suggest that the effects of performing open, expansive body postures may be driven by processes other than the poses' association with interpersonal power and dominance. This study demonstrates that positive effects of yoga practice can occur after performing yoga poses for only 2 min.

  19. Non-standard and improperly posed problems

    CERN Document Server

    Straughan, Brian; Ames, William F

    1997-01-01

    Written by two international experts in the field, this book is the first unified survey of the advances made in the last 15 years on key non-standard and improperly posed problems for partial differential equations.This reference for mathematicians, scientists, and engineers provides an overview of the methodology typically used to study improperly posed problems. It focuses on structural stability--the continuous dependence of solutions on the initial conditions and the modeling equations--and on problems for which data are only prescribed on part of the boundary.The book addresses continuou

  20. Flexible Polyhedral Surfaces with Two Flat Poses

    Directory of Open Access Journals (Sweden)

    Hellmuth Stachel

    2015-05-01

    Full Text Available We present three types of polyhedral surfaces, which are continuously flexible and have not only an initial pose, where all faces are coplanar, but pass during their self-motion through another pose with coplanar faces (“flat pose”. These surfaces are examples of so-called rigid origami, since we only admit exact flexions, i.e., each face remains rigid during the motion; only the dihedral angles vary. We analyze the geometry behind Miura-ori and address Kokotsakis’ example of a flexible tessellation with the particular case of a cyclic quadrangle. Finally, we recall Bricard’s octahedra of Type 3 and their relation to strophoids.

  1. The nucleolus is well-posed

    Science.gov (United States)

    Fragnelli, Vito; Patrone, Fioravante; Torre, Anna

    2006-02-01

    The lexicographic order is not representable by a real-valued function, contrary to many other orders or preorders. So, standard tools and results for well-posed minimum problems cannot be used. We prove that under suitable hypotheses it is however possible to guarantee the well-posedness of a lexicographic minimum over a compact or convex set. This result allows us to prove that some game theoretical solution concepts, based on lexicographic order are well-posed: in particular, this is true for the nucleolus.

  2. Head Pose Estimation from Passive Stereo Images

    DEFF Research Database (Denmark)

    Breitenstein, Michael D.; Jensen, Jeppe; Høilund, Carsten

    2009-01-01

    function. Our algorithm incorporates 2D and 3D cues to make the system robust to low-quality range images acquired by passive stereo systems. It handles large pose variations (of ±90 ° yaw and ±45 ° pitch rotation) and facial variations due to expressions or accessories. For a maximally allowed error of 30...

  3. Method of orthogonally splitting imaging pose measurement

    Science.gov (United States)

    Zhao, Na; Sun, Changku; Wang, Peng; Yang, Qian; Liu, Xintong

    2018-01-01

    In order to meet the aviation's and machinery manufacturing's pose measurement need of high precision, fast speed and wide measurement range, and to resolve the contradiction between measurement range and resolution of vision sensor, this paper proposes an orthogonally splitting imaging pose measurement method. This paper designs and realizes an orthogonally splitting imaging vision sensor and establishes a pose measurement system. The vision sensor consists of one imaging lens, a beam splitter prism, cylindrical lenses and dual linear CCD. Dual linear CCD respectively acquire one dimensional image coordinate data of the target point, and two data can restore the two dimensional image coordinates of the target point. According to the characteristics of imaging system, this paper establishes the nonlinear distortion model to correct distortion. Based on cross ratio invariability, polynomial equation is established and solved by the least square fitting method. After completing distortion correction, this paper establishes the measurement mathematical model of vision sensor, and determines intrinsic parameters to calibrate. An array of feature points for calibration is built by placing a planar target in any different positions for a few times. An terative optimization method is presented to solve the parameters of model. The experimental results show that the field angle is 52 °, the focus distance is 27.40 mm, image resolution is 5185×5117 pixels, displacement measurement error is less than 0.1mm, and rotation angle measurement error is less than 0.15°. The method of orthogonally splitting imaging pose measurement can satisfy the pose measurement requirement of high precision, fast speed and wide measurement range.

  4. Gaussian particle filter based pose and motion estimation

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Determination of relative three-dimensional (3D) position, orientation, and relative motion between two reference frames is an important problem in robotic guidance, manipulation, and assembly as well as in other fields such as photogrammetry.A solution to pose and motion estimation problem that uses two-dimensional (2D) intensity images from a single camera is desirable for real-time applications. The difficulty in performing this measurement is that the process of projecting 3D object features to 2D images is a nonlinear transformation. In this paper, the 3D transformation is modeled as a nonlinear stochastic system with the state estimation providing six degrees-of-freedom motion and position values, using line features in image plane as measuring inputs and dual quaternion to represent both rotation and translation in a unified notation. A filtering method called the Gaussian particle filter (GPF) based on the particle filtering concept is presented for 3D pose and motion estimation of a moving target from monocular image sequences. The method has been implemented with simulated data, and simulation results are provided along with comparisons to the extended Kalman filter (EKF) and the unscented Kalman filter (UKF) to show the relative advantages of the GPF. Simulation results showed that GPF is a superior alternative to EKF and UKF.

  5. Mathematics difficulties & classroom leadership

    DEFF Research Database (Denmark)

    Schmidt, Maria Christina Secher

    2016-01-01

    This article investigates possible links between inclusion, students, for whom mathematics is extensively difficult, and classroom leadership through a case study on teaching strategies and student participation in four classrooms at two different primary schools in Denmark. Three sets of results...... are presented: 1) descriptions of the teachers’ classroom leadership to include all their students in the learning community, 2) the learning community produced by stated and practiced rules for teaching and learning behavior, 3) the classroom behavior of students who experience difficulties with mathematics....... The findings suggest that the teachers’ pedagogical choices and actions support an active learning environment for students in diverse learning needs, and that the teachers practise dimensions of inclusive classroom leadership that are known to be successful for teaching mathematics to all students. Despite...

  6. Tridimensional pose estimation of a person head

    International Nuclear Information System (INIS)

    Perez Berenguer, Elisa; Soria, Carlos; Nasisi, Oscar; Mut, Vicente

    2007-01-01

    In this work, we present a method for estimating 3-D motion parameters; this method provides an alternative way for 3D head pose estimation from image sequence in the current computer vision literature. This method is robust over extended sequences and large head motions and accurately extracts the orientation angles of head from a single view. Experimental results show that this tracking system works well for development a human-computer interface for people that possess severe motor incapacity

  7. Driver head pose tracking with thermal camera

    Science.gov (United States)

    Bole, S.; Fournier, C.; Lavergne, C.; Druart, G.; Lépine, T.

    2016-09-01

    Head pose can be seen as a coarse estimation of gaze direction. In automotive industry, knowledge about gaze direction could optimize Human-Machine Interface (HMI) and Advanced Driver Assistance Systems (ADAS). Pose estimation systems are often based on camera when applications have to be contactless. In this paper, we explore uncooled thermal imagery (8-14μm) for its intrinsic night vision capabilities and for its invariance versus lighting variations. Two methods are implemented and compared, both are aided by a 3D model of the head. The 3D model, mapped with thermal texture, allows to synthesize a base of 2D projected models, differently oriented and labeled in yaw and pitch. The first method is based on keypoints. Keypoints of models are matched with those of the query image. These sets of matchings, aided with the 3D shape of the model, allow to estimate 3D pose. The second method is a global appearance approach. Among all 2D models of the base, algorithm searches the one which is the closest to the query image thanks to a weighted least squares difference.

  8. Fraction Multiplication and Division Word Problems Posed by Different Years of Pre-Service Elementary Mathematics Teachers

    Directory of Open Access Journals (Sweden)

    Tuba Aydogdu Iskenderoglu

    2018-04-01

    Full Text Available It is important for pre-service teachers to know the conceptual difficulties they have experienced regarding the concepts of multiplication and division in fractions and problem posing is a way to learn these conceptual difficulties. Problem posing is a synthetic activity that fundamentally has multiple answers. The purpose of this study is to analyze the multiplication and division of fractions problems posed by pre-service elementary mathematics teachers and to investigate how the problems posed change according to the year of study the pre-service teachers are in. The study employed developmental research methods. A total of 213 pre-service teachers enrolled in different years of the Elementary Mathematics Teaching program at a state university in Turkey took part in the study. The “Problem Posing Test” was used as the data collecting tool. In this test, there are 3 multiplication and 3 division operations. The data were analyzed using qualitative descriptive analysis. The findings suggest that, regardless of the year, pre-service teachers had more conceptual difficulties in problem posing about the division of fractions than in problem posing about the multiplication of fractions.

  9. Student difficulties with Gauss' law

    Science.gov (United States)

    Kanim, Stephen

    2000-09-01

    Many students in introductory courses have difficulty solving Gauss' law problems. Through interviews with students and analysis of solutions to homework and examination questions we have identified some specific conceptual difficulties that often contribute to students' inability to solve quantitative Gauss' law problems. We give examples of common difficulties and discuss instructional implications.

  10. Hydrology under difficulties

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1964-08-15

    An unusual hydrological investigation is being carried out in Kenya by IAEA, at Lake Chala, a volcanic crater with no visible inlet or outlet. The problem is to determine whether the lake has any connection with a number of springs near Taveta, some six miles distant: this relationship is important in assessing the possibility of expanding the Taveta irrigation scheme. Questions of water rights and utilization are involved, since the lake is situated on the Tanganyikan border. The method adopted is that of labelling the waters of the lake with small quantities of water containing radioactive hydrogen (tritium). There are some special features in this instance, one being the difficulty of access. The lake is entirely surrounded by steep cliffs. A track was cut by British Army engineers, and the boat and all supplies were taken down by this route. Another problem was presented by the depth of the lake, which amounts to 300 feet. It is necessary to ensure the regular mixing of the tritium throughout. This has been done by means of hundreds of plastic bottles, which were dropped from the boat at regular intervals as it made a series of carefully-plotted traverses. Each bottle had a weight attached, and was perforated by two small holes. By this means, as the bottle sank the contents were progressively released until it reached the bottom, thus ensuring an even diffusion of tritium throughout the lake.

  11. The greatest hydroelectric power plant in the world. Itaipu Hydroelectric Power Plant

    International Nuclear Information System (INIS)

    Andonov - Chento, Ilija

    2004-01-01

    Details to demonstrate the size and engineering achievements of one of the world's greatest hydroelectric power plant are given. Principal technical features of construction and operation of the Itaipu Dam are tabulated and discussed

  12. [Difficulties in learning mathematics].

    Science.gov (United States)

    Rebollo, M A; Rodríguez, A L

    2006-02-13

    To discuss our concern for some aspects of mathematics learning disorders related to the nomenclature employed and their diagnosis; these aspects refer to the term 'dyscalculia' and to its diagnosis (especially syndromatic diagnosis). We also intend to propose a classification that could help to define the terminology. Lastly we are going to consider the different aspects of diagnosis and to determine which of them are indispensable in the diagnosis of primary and secondary disorders. As far as the nomenclature is concerned, we refer to the term 'dyscalculia'. The origins of the term are analysed along with the reasons why it should not be used in children with difficulties in learning mathematics. We propose a classification and denominations for the different types that should undoubtedly be discussed. With respect to the diagnosis, several problems related to the syndromatic diagnosis are considered, since in our country there are no standardised tests with which to study performance in arithmetic and geometry. This means that criterion reference tests are conducted to try to establish current and potential performance. At this stage of the diagnosis pedagogical and psychological studies must be conducted. The important factors with regard to the topographical and aetiological diagnoses are prior knowledge, results from the studies that have been carried out and findings from imaging studies. The importance of a genetic study must be defined in the aetiological diagnosis. We propose a nomenclature to replace the term 'dyscalculia'. Standardised tests are needed for the diagnosis. The need to establish current and potential performance is hierarchized. With regard to the topographical diagnosis, we highlight the need for more information about geometry, and in aetiological studies the analyses must be conducted with greater numbers of children.

  13. Robotic-surgical instrument wrist pose estimation.

    Science.gov (United States)

    Fabel, Stephan; Baek, Kyungim; Berkelman, Peter

    2010-01-01

    The Compact Lightweight Surgery Robot from the University of Hawaii includes two teleoperated instruments and one endoscope manipulator which act in accord to perform assisted interventional medicine. The relative positions and orientations of the robotic instruments and endoscope must be known to the teleoperation system so that the directions of the instrument motions can be controlled to correspond closely to the directions of the motions of the master manipulators, as seen by the the endoscope and displayed to the surgeon. If the manipulator bases are mounted in known locations and all manipulator joint variables are known, then the necessary coordinate transformations between the master and slave manipulators can be easily computed. The versatility and ease of use of the system can be increased, however, by allowing the endoscope or instrument manipulator bases to be moved to arbitrary positions and orientations without reinitializing each manipulator or remeasuring their relative positions. The aim of this work is to find the pose of the instrument end effectors using the video image from the endoscope camera. The P3P pose estimation algorithm is used with a Levenberg-Marquardt optimization to ensure convergence. The correct transformations between the master and slave coordinate frames can then be calculated and updated when the bases of the endoscope or instrument manipulators are moved to new, unknown, positions at any time before or during surgical procedures.

  14. Skill Levels of Prospective Physics Teachers on Problem Posing

    Science.gov (United States)

    Cildir, Sema; Sezen, Nazan

    2011-01-01

    Problem posing is one of the topics which the educators thoroughly accentuate. Problem posing skill is defined as an introvert activity of a student's learning. In this study, skill levels of prospective physics teachers on problem posing were determined and their views on problem posing were evaluated. To this end, prospective teachers were given…

  15. Identifying and addressing student difficulties with the ideal gas law

    Science.gov (United States)

    Kautz, Christian Hans

    This dissertation reports on an in-depth investigation of student understanding of the ideal gas law. The research and curriculum development were mostly conducted in the context of algebra- and calculus-based introductory physics courses and a sophomore-level thermal physics course. Research methods included individual demonstration interviews and written questions. Student difficulties with the quantities: pressure, volume, temperature, and the number of moles were identified. Data suggest that students' incorrect and incomplete microscopic models about gases contribute to the difficulties they have in answering questions posed in macroscopic terms. In addition, evidence for general reasoning difficulties is presented. These research results have guided the development of curriculum to address the student difficulties that have been identified.

  16. Relative Pose Estimation Algorithm with Gyroscope Sensor

    Directory of Open Access Journals (Sweden)

    Shanshan Wei

    2016-01-01

    Full Text Available This paper proposes a novel vision and inertial fusion algorithm S2fM (Simplified Structure from Motion for camera relative pose estimation. Different from current existing algorithms, our algorithm estimates rotation parameter and translation parameter separately. S2fM employs gyroscopes to estimate camera rotation parameter, which is later fused with the image data to estimate camera translation parameter. Our contributions are in two aspects. (1 Under the circumstance that no inertial sensor can estimate accurately enough translation parameter, we propose a translation estimation algorithm by fusing gyroscope sensor and image data. (2 Our S2fM algorithm is efficient and suitable for smart devices. Experimental results validate efficiency of the proposed S2fM algorithm.

  17. Symmetry and the Monster: One of the Greatest Quests of Mathematics

    Energy Technology Data Exchange (ETDEWEB)

    Szabo, R J [Colin Maclaurin Building, Heriot-Watt University, Edinburgh EH14 4AS (United Kingdom)

    2007-04-13

    The book Symmetry and the Monster: One of the Greatest Quests of Mathematics describes historical events leading up to the discovery of the Monster sporadic group, the largest simple sporadic group. It also expounds the significance and deep relationships between this group and other areas of mathematics and theoretical physics. It begins, in the prologue, with a nice overview of some of the mathematical drama surrounding the discovery of the Monster and its subsequent relationship to number theory (the so-called Moonshine conjectures). From a historical perspective, the book traces back to the roots of group theory, Galois theory, and steadily runs through time through the many famous mathematicians who contributed to group theory, including Lie, Killing and Cartan. Throughout, the author has provided a very nice and deep insight into the sociological and scientific problems at the time, and gives the reader a very prominent inside view of the real people behind the mathematics. The book should be an enjoyable read to anyone with an interest in the history of mathematics. For the non-mathematician the book makes a good, and mostly successful, attempt at being non-technical. Technical mathematical jargon is replaced with more heuristic, intuitive terminology, making the mathematical descriptions in the book fairly easy going. A glossary/hspace{l_brace}0.25pc{r_brace} of/hspace{l_brace}0.25pc{r_brace} terminology for noindent the more scientifically inclined is included in various footnotes throughout the book and in a comprehensive listing at the end of the book. Some more technical material is also included in the form of appendices at the end of the book. Some aspects of physics are also explained in a simple, intuitive way. The author further attempts at various places to give the non-specialist a glimpse into what mathematical proof is all about, and explains the difficulties and technicalities involved in this very nicely (for instance, he mentions the various

  18. Symmetry and the Monster: One of the Greatest Quests of Mathematics

    International Nuclear Information System (INIS)

    Szabo, R J

    2007-01-01

    The book Symmetry and the Monster: One of the Greatest Quests of Mathematics describes historical events leading up to the discovery of the Monster sporadic group, the largest simple sporadic group. It also expounds the significance and deep relationships between this group and other areas of mathematics and theoretical physics. It begins, in the prologue, with a nice overview of some of the mathematical drama surrounding the discovery of the Monster and its subsequent relationship to number theory (the so-called Moonshine conjectures). From a historical perspective, the book traces back to the roots of group theory, Galois theory, and steadily runs through time through the many famous mathematicians who contributed to group theory, including Lie, Killing and Cartan. Throughout, the author has provided a very nice and deep insight into the sociological and scientific problems at the time, and gives the reader a very prominent inside view of the real people behind the mathematics. The book should be an enjoyable read to anyone with an interest in the history of mathematics. For the non-mathematician the book makes a good, and mostly successful, attempt at being non-technical. Technical mathematical jargon is replaced with more heuristic, intuitive terminology, making the mathematical descriptions in the book fairly easy going. A glossary/hspace{0.25pc} of/hspace{0.25pc} terminology for noindent the more scientifically inclined is included in various footnotes throughout the book and in a comprehensive listing at the end of the book. Some more technical material is also included in the form of appendices at the end of the book. Some aspects of physics are also explained in a simple, intuitive way. The author further attempts at various places to give the non-specialist a glimpse into what mathematical proof is all about, and explains the difficulties and technicalities involved in this very nicely (for instance, he mentions the various 100+ page articles that

  19. BOOK REVIEW: Symmetry and the Monster: One of the Greatest Quests of Mathematics

    Science.gov (United States)

    Szabo, R. J.

    2007-04-01

    The book Symmetry and the Monster: One of the Greatest Quests of Mathematics describes historical events leading up to the discovery of the Monster sporadic group, the largest simple sporadic group. It also expounds the significance and deep relationships between this group and other areas of mathematics and theoretical physics. It begins, in the prologue, with a nice overview of some of the mathematical drama surrounding the discovery of the Monster and its subsequent relationship to number theory (the so-called Moonshine conjectures). From a historical perspective, the book traces back to the roots of group theory, Galois theory, and steadily runs through time through the many famous mathematicians who contributed to group theory, including Lie, Killing and Cartan. Throughout, the author has provided a very nice and deep insight into the sociological and scientific problems at the time, and gives the reader a very prominent inside view of the real people behind the mathematics. The book should be an enjoyable read to anyone with an interest in the history of mathematics. For the non-mathematician the book makes a good, and mostly successful, attempt at being non-technical. Technical mathematical jargon is replaced with more heuristic, intuitive terminology, making the mathematical descriptions in the book fairly easy going. A glossary\\hspace{0.25pc} of\\hspace{0.25pc} terminology for noindent the more scientifically inclined is included in various footnotes throughout the book and in a comprehensive listing at the end of the book. Some more technical material is also included in the form of appendices at the end of the book. Some aspects of physics are also explained in a simple, intuitive way. The author further attempts at various places to give the non-specialist a glimpse into what mathematical proof is all about, and explains the difficulties and technicalities involved in this very nicely (for instance, he mentions the various 100+ page articles that

  20. School Issues Under [Section] 504 and the ADA: The Latest and Greatest.

    Science.gov (United States)

    Aleman, Steven R.

    This paper highlights recent guidance and rulings from the Office of Civil Rights (OCR) of interest to administrators, advocates, and attorneys. It is a companion piece to Student Issues on SectionNB504/ADA: The Latest and Greatest. Compliance with SectionNB504 and the Americans with Disabilities Act (ADA) continues to involve debate and dialog on…

  1. Stigma and Discrimination in HIV/AIDS; The greatest Challenge to ...

    African Journals Online (AJOL)

    The greatest challenge to the efforts of the various agencies and governments in the care, support and treatment of people living with HIV/AIDS, appears to be stigma and discrimination. Stigma and discrimination has to be addressed through public education, legislation to protect people living with HIV/AIDS and also by ...

  2. FedWeb Greatest Hits: Presenting the New Test Collection for Federated Web Search

    NARCIS (Netherlands)

    Demeester, Thomas; Trieschnigg, Rudolf Berend; Zhou, Ke; Nguyen, Dong-Phuong; Hiemstra, Djoerd

    This paper presents 'FedWeb Greatest Hits', a large new test collection for research in web information retrieval. As a combination and extension of the datasets used in the TREC Federated Web Search Track, this collection opens up new research possibilities on federated web search challenges, as

  3. University Students' Problem Posing Abilities and Attitudes towards Mathematics.

    Science.gov (United States)

    Grundmeier, Todd A.

    2002-01-01

    Explores the problem posing abilities and attitudes towards mathematics of students in a university pre-calculus class and a university mathematical proof class. Reports a significant difference in numeric posing versus non-numeric posing ability in both classes. (Author/MM)

  4. Human action recognition based on estimated weak poses

    Science.gov (United States)

    Gong, Wenjuan; Gonzàlez, Jordi; Roca, Francesc Xavier

    2012-12-01

    We present a novel method for human action recognition (HAR) based on estimated poses from image sequences. We use 3D human pose data as additional information and propose a compact human pose representation, called a weak pose, in a low-dimensional space while still keeping the most discriminative information for a given pose. With predicted poses from image features, we map the problem from image feature space to pose space, where a Bag of Poses (BOP) model is learned for the final goal of HAR. The BOP model is a modified version of the classical bag of words pipeline by building the vocabulary based on the most representative weak poses for a given action. Compared with the standard k-means clustering, our vocabulary selection criteria is proven to be more efficient and robust against the inherent challenges of action recognition. Moreover, since for action recognition the ordering of the poses is discriminative, the BOP model incorporates temporal information: in essence, groups of consecutive poses are considered together when computing the vocabulary and assignment. We tested our method on two well-known datasets: HumanEva and IXMAS, to demonstrate that weak poses aid to improve action recognition accuracies. The proposed method is scene-independent and is comparable with the state-of-art method.

  5. 2D Methods for pose invariant face recognition

    CSIR Research Space (South Africa)

    Mokoena, Ntabiseng

    2016-12-01

    Full Text Available The ability to recognise face images under random pose is a task that is done effortlessly by human beings. However, for a computer system, recognising face images under varying poses still remains an open research area. Face recognition across pose...

  6. Transfer between Pose and Illumination Training in Face Recognition

    Science.gov (United States)

    Liu, Chang Hong; Bhuiyan, Md. Al-Amin; Ward, James; Sui, Jie

    2009-01-01

    The relationship between pose and illumination learning in face recognition was examined in a yes-no recognition paradigm. The authors assessed whether pose training can transfer to a new illumination or vice versa. Results show that an extensive level of pose training through a face-name association task was able to generalize to a new…

  7. Difficulty Swallowing After Stroke (Dysphagia)

    Science.gov (United States)

    ... Stroke Heroes Among Us Difficulty Swallowing After Stroke (Dysphagia) Updated:Nov 15,2016 Excerpted and adapted from "Swallowing Disorders After a Stroke," Stroke Connection Magazine July/August ...

  8. Workplace bullying and sleep difficulties

    DEFF Research Database (Denmark)

    Hansen, Åse Marie; Hogh, Annie; Garde, Anne Helene

    2014-01-01

    PURPOSE: The aims of the present study were to investigate whether being subjected to bullying and witnessing bullying at the workplace was associated with concurrent sleep difficulties, whether frequently bullied/witnesses have more sleep difficulties than occasionally bullied....../witnesses, and whether there were associations between being subjected to bullying or witnessing bullying at the workplace and subsequent sleep difficulties. METHODS: A total of 3,382 respondents (67 % women and 33 % men) completed a baseline questionnaire about their psychosocial work environment and health....... The overall response rate was 46 %. At follow-up 2 years later, 1671 of those responded to a second questionnaire (49 % of the 3,382 respondents at baseline). Sleep difficulties were measured in terms of disturbed sleep, awakening problems, and poor quality of sleep. RESULTS: Bullied persons and witnesses...

  9. Blink activity and task difficulty.

    Science.gov (United States)

    Tanaka, Y; Yamaoka, K

    1993-08-01

    This study investigated the relationship between task difficulty and blink activity, which includes blink rate, blink amplitude, and blink duration. Two kinds of tasks established two levels of difficulty. In Exp. 1, a mental arithmetic task was used to examine the relationship. Analysis showed that blink rate for a difficult task was significantly higher than that for an easier one. In Exp. 2, a letter-search task (hiragana Japanese alphabet) was used while the other conditions were the same as those in Exp. 1; however, the results of this experiment were not influenced by the difficulty of the task. As results indicate that blink rate is related to not only difficulty but also the nature of the task, the nature of the task is probably dependent on a mechanism in information processing. The results for blink amplitude and blink duration showed no systematic change during either experiment.

  10. Desirable difficulties in vocabulary learning

    OpenAIRE

    Bjork, RA; Kroll, JF

    2015-01-01

    © 2015 by the Board of Trustees of the University of Illinois. In this article we discuss the role of desirable difficulties in vocabulary learning from two perspectives, one having to do with identifying conditions of learning that impose initial challenges to the learner but then benefit later retention and transfer, and the other having to do with the role of certain difficulties that are intrinsic to language processes, are engaged during word learning, and reflect how language is underst...

  11. Greatest Happiness Principle in a Complex System: Maximisation versus Driving Force

    Directory of Open Access Journals (Sweden)

    Katalin Martinás

    2012-06-01

    Full Text Available From philosophical point of view, micro-founded economic theories depart from the principle of the pursuit of the greatest happiness. From mathematical point of view, micro-founded economic theories depart from the utility maximisation program. Though economists are aware of the serious limitations of the equilibrium analysis, they remain in that framework. We show that the maximisation principle, which implies the equilibrium hypothesis, is responsible for this impasse. We formalise the pursuit of the greatest happiness principle by the help of the driving force postulate: the volumes of activities depend on the expected wealth increase. In that case we can get rid of the equilibrium hypothesis and have new insights into economic theory. For example, in what extent standard economic results depend on the equilibrium hypothesis?

  12. Social Media - DoD’s Greatest Information Sharing Tool or Weakest Security Link?

    Science.gov (United States)

    2010-04-15

    or position of the Department of the Army, Department of Defense, or the U.S. Government. SOCIAL MEDIA – DOD’S GREATEST INFORMATION SHARING TOOL...appropriateness and effectiveness of these policies in securing the information network. 15. SUBJECT TERMS Social media , information...TYPE Civilian Research Paper 3. DATES COVERED (From - To) August 2009-April 2010 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER Social Media

  13. The conditions for attaining the greatest degree of system stability with strict generator excitation control

    Energy Technology Data Exchange (ETDEWEB)

    Gruzdev, I.A.; Ekimova, M.M.; Truspekova, G.A.

    1982-01-01

    Expressions are derived for an idealized model of a complex electric power system; these expressions define the greatest level of stability of an electric power system and the optimum combination of stabilization factors with automatic excitation control in a single power system. The possibility of increasing the level of stability of an electric power system with simultaneous strict automatic excitation control of the synychronous generators in several power systems is analyzed.

  14. Asymptotics for the greatest zeros of solutions of a particular O.D.E.

    Directory of Open Access Journals (Sweden)

    Silvia Noschese

    1994-05-01

    Full Text Available This paper deals with the Liouville-Stekeloff method for approximating solutions of homogeneous linear ODE and a general result due to Tricomi which provides estimates for the zeros of functions by means of the knowledge of an asymptotic representation. From the classical tools we deduce information about the asymptotics of the greatest zeros of a class of solutions of a particular ODE, including the classical Hermite polynomials.

  15. Personal privacy, information assurance, and the threat posed by malware techology

    Science.gov (United States)

    Stytz, Martin R.; Banks, Sheila B.

    2006-04-01

    In spite of our best efforts to secure the cyber world, the threats posed to personal privacy by attacks upon networks and software continue unabated. While there are many reasons for this state of affairs, clearly one of the reasons for continued vulnerabilities in software is the inability to assess their security properties and test their security systems while they are in development. A second reason for this growing threat to personal privacy is the growing sophistication and maliciousness of malware coupled with the increasing difficulty of detecting malware. The pervasive threat posed by malware coupled with the difficulties faced when trying to detect its presence or an attempted intrusion make addressing the malware threat one of the most pressing issues that must be solved in order to insure personal privacy to users of the internet. In this paper, we will discuss the threat posed by malware, the types of malware found in the wild (outside of computer laboratories), and current techniques that are available for from a successful malware penetration. The paper includes a discussion of anti-malware tools and suggestions for future anti-malware efforts.

  16. Adolescent Bullying and Sleep Difficulties

    Directory of Open Access Journals (Sweden)

    Simon C. Hunter

    2014-11-01

    Full Text Available This study evaluated whether adolescents who report having been bullied, being bullies, or report both being a bully and being bullied experience more sleep difficulties than children uninvolved in bullying. The study drew upon cognitive theories of insomnia, investigating whether the extent to which young people report worrying about bullying can moderate associations between victimization and sleep difficulties. Participants were 5420 adolescents who completed a self-report questionnaire. Pure Victims (OR = 1.72, 95% CI [1.07, 2.75], Pure Bullies (OR = 1.80, 95% CI [1.16, 2.81], and Bully-Victims (OR = 2.90, 95% CI [1.17, 4.92] were all more likely to experience sleep difficulties when compared to uninvolved young people. The extent to which young people reported worrying about being bullied did not moderate the links between victimization and sleep difficulties. In this way, bullying is clearly related to sleep difficulties among adolescents but the conceptual reach of the cognitive model of insomnia in this domain is questioned.

  17. Pose Planning for the Feed Support System of FAST

    Directory of Open Access Journals (Sweden)

    Rui Yao

    2014-01-01

    Full Text Available A six-cable driven parallel manipulator and an A-B rotator in the feed support system of the Five-hundred-meter Aperture Spherical radio Telescope (FAST are adopted for realizing the position and pose of nine feeds. The six-cable driven parallel manipulator is a flexible mechanism, which may not be stably controlled due to a small cable tension. The A-B rotator is a rigid mechanism, and its stability and accuracy can be improved by small pose angle. Based on the different characteristics, a pose planning function is presented. The optimization target of the pose planning function is to get the smallest pose angle of the A-B rotator, and the constraint condition can reflect the controllability of the six-cable driven parallel manipulator. Then, the pose planning realization process of the feed support system is proposed. Based on the pose planning method, optimized pose angles of the feed support system for the nine feeds are obtained, which suggests that the pose angle of the six-cable driven parallel manipulator changes from 0° to 14° and the pose angle of the A-B rotator changes from 0° to 26.4°.

  18. To Strike a Pose: No Stereotype Backlash for Power Posing Women

    Directory of Open Access Journals (Sweden)

    Miriam Rennung

    2016-09-01

    Full Text Available Power posing, the adoption of open and powerful postures, has effects that parallel those of actual social power. This study explored the social evaluation of adopting powerful versus powerless body postures in men and women regarding perceived warmth, competence, and the likelihood of eliciting admiration, envy, pity, and contempt. Previous findings suggest that the display of power by women may have side effects due to gender stereotyping, namely reduced warmth ratings and negative emotional reactions. An experiment (N = 2,473 asked participants to rate pictures of men and women who adopted high-power or low-power body postures. High-power posers were rated higher on competence, admiration, envy, and contempt compared to low-power posers, whereas the opposite was true for pity. There was no impact of power posing on perceived warmth. Contrary to expectations, the poser’s gender did not moderate any of the effects. These findings suggest that nonverbal displays of power do influence fundamental dimensions of social perception and their accompanying emotional reactions but result in comparably positive and negative evaluations for both genders.

  19. Evaluating the tuberculosis hazard posed to cattle from wildlife across Europe.

    Science.gov (United States)

    Hardstaff, Joanne L; Marion, Glenn; Hutchings, Michael R; White, Piran C L

    2014-10-01

    Tuberculosis (TB) caused by infection with Mycobacterium bovis (M. bovis) and other closely related members of the M. tuberculosis complex (MTC) infects many domestic and wildlife species across Europe. Transmission from wildlife species to cattle complicates the control of disease in cattle. By determining the level of TB hazard for which a given wildlife species is responsible, the potential for transmission to the cattle population can be evaluated. We undertook a quantitative review of TB hazard across Europe on a country-by-country basis for cattle and five widely-distributed wildlife species. Cattle posed the greatest current and potential TB hazard other cattle for the majority of countries in Europe. Wild boar posed the greatest hazard of all the wildlife species, indicating that wild boar have the greatest ability to transmit the disease to cattle. The most common host systems for TB hazards in Europe are the cattle-deer-wild boar ones. The cattle-roe deer-wild boar system is found in 10 countries, and the cattle-red deer-wild boar system is found in five countries. The dominance of cattle with respect to the hazards in many regions confirms that intensive surveillance of cattle for TB should play an important role in any TB control programme. The significant contribution that wildlife can make to the TB hazard to cattle is also of concern, given current population and distribution increases of some susceptible wildlife species, especially wild boar and deer, and the paucity of wildlife TB surveillance programmes. Copyright © 2013 Elsevier Ltd. All rights reserved.

  20. Head pose estimation algorithm based on deep learning

    Science.gov (United States)

    Cao, Yuanming; Liu, Yijun

    2017-05-01

    Head pose estimation has been widely used in the field of artificial intelligence, pattern recognition and intelligent human-computer interaction and so on. Good head pose estimation algorithm should deal with light, noise, identity, shelter and other factors robustly, but so far how to improve the accuracy and robustness of attitude estimation remains a major challenge in the field of computer vision. A method based on deep learning for pose estimation is presented. Deep learning with a strong learning ability, it can extract high-level image features of the input image by through a series of non-linear operation, then classifying the input image using the extracted feature. Such characteristics have greater differences in pose, while they are robust of light, identity, occlusion and other factors. The proposed head pose estimation is evaluated on the CAS-PEAL data set. Experimental results show that this method is effective to improve the accuracy of pose estimation.

  1. Local Feature Learning for Face Recognition under Varying Poses

    DEFF Research Database (Denmark)

    Duan, Xiaodong; Tan, Zheng-Hua

    2015-01-01

    In this paper, we present a local feature learning method for face recognition to deal with varying poses. As opposed to the commonly used approaches of recovering frontal face images from profile views, the proposed method extracts the subject related part from a local feature by removing the pose...... related part in it on the basis of a pose feature. The method has a closed-form solution, hence being time efficient. For performance evaluation, cross pose face recognition experiments are conducted on two public face recognition databases FERET and FEI. The proposed method shows a significant...... recognition improvement under varying poses over general local feature approaches and outperforms or is comparable with related state-of-the-art pose invariant face recognition approaches. Copyright ©2015 by IEEE....

  2. Northeast and Midwest regional species and habitats at greatest risk and most vulnerable to climate impacts

    Science.gov (United States)

    Staudinger, Michelle D.; Hilberg, Laura; Janowiak, Maria; Swanton, C.O.

    2016-01-01

    The objectives of this Chapter are to describe climate change vulnerability, it’s components, the range of assessment methods being implemented regionally, and examples of training resources and tools. Climate Change Vulnerability Assessments (CCVAs) have already been conducted for numerous Regional Species of Greatest Conservation Need and their dependent 5 habitats across the Northeast and Midwest. This chapter provides a synthesis of different assessment frameworks, information on the locations (e.g., States) where vulnerability assessments were conducted, lists of individual species and habitats with their respective vulnerability rankings, and a comparison of how vulnerability rankings were determined among studies.

  3. The lighter side of advertising: investigating posing and lighting biases.

    Science.gov (United States)

    Thomas, Nicole A; Burkitt, Jennifer A; Patrick, Regan E; Elias, Lorin J

    2008-11-01

    People tend to display the left cheek when posing for a portrait; however, this effect does not appear to generalise to advertising. The amount of body visible in the image and the sex of the poser might also contribute to the posing bias. Portraits also exhibit lateral lighting biases, with most images being lit from the left. This effect might also be present in advertisements. A total of 2801 full-page advertisements were sampled and coded for posing direction, lighting direction, sex of model, and amount of body showing. Images of females showed an overall leftward posing bias, but the biases in males depended on the amount of body visible. Males demonstrated rightward posing biases for head-only images. Overall, images tended to be lit from the top left corner. The two factors of posing and lighting biases appear to influence one another. Leftward-lit images had more leftward poses than rightward, while the opposite occurred for rightward-lit images. Collectively, these results demonstrate that the posing biases in advertisements are dependent on the amount of body showing in the image, and that biases in lighting direction interact with these posing biases.

  4. In-the-wild facial expression recognition in extreme poses

    Science.gov (United States)

    Yang, Fei; Zhang, Qian; Zheng, Chi; Qiu, Guoping

    2018-04-01

    In the computer research area, facial expression recognition is a hot research problem. Recent years, the research has moved from the lab environment to in-the-wild circumstances. It is challenging, especially under extreme poses. But current expression detection systems are trying to avoid the pose effects and gain the general applicable ability. In this work, we solve the problem in the opposite approach. We consider the head poses and detect the expressions within special head poses. Our work includes two parts: detect the head pose and group it into one pre-defined head pose class; do facial expression recognize within each pose class. Our experiments show that the recognition results with pose class grouping are much better than that of direct recognition without considering poses. We combine the hand-crafted features, SIFT, LBP and geometric feature, with deep learning feature as the representation of the expressions. The handcrafted features are added into the deep learning framework along with the high level deep learning features. As a comparison, we implement SVM and random forest to as the prediction models. To train and test our methodology, we labeled the face dataset with 6 basic expressions.

  5. Fish species of greatest conservation need in wadeable Iowa streams: current status and effectiveness of Aquatic Gap Program distribution models

    Science.gov (United States)

    Sindt, Anthony R.; Pierce, Clay; Quist, Michael C.

    2012-01-01

    Effective conservation of fish species of greatest conservation need (SGCN) requires an understanding of species–habitat relationships and distributional trends. Thus, modeling the distribution of fish species across large spatial scales may be a valuable tool for conservation planning. Our goals were to evaluate the status of 10 fish SGCN in wadeable Iowa streams and to test the effectiveness of Iowa Aquatic Gap Analysis Project (IAGAP) species distribution models. We sampled fish assemblages from 86 wadeable stream segments in the Mississippi River drainage of Iowa during 2009 and 2010 to provide contemporary, independent fish species presence–absence data. The frequencies of occurrence in stream segments where species were historically documented varied from 0.0% for redfin shiner Lythrurus umbratilis to 100.0% for American brook lampreyLampetra appendix, with a mean of 53.0%, suggesting that the status of Iowa fish SGCN is highly variable. Cohen's kappa values and other model performance measures were calculated by comparing field-collected presence–absence data with IAGAP model–predicted presences and absences for 12 fish SGCN. Kappa values varied from 0.00 to 0.50, with a mean of 0.15. The models only predicted the occurrences of banded darterEtheostoma zonale, southern redbelly dace Phoxinus erythrogaster, and longnose daceRhinichthys cataractae more accurately than would be expected by chance. Overall, the accuracy of the twelve models was low, with a mean correct classification rate of 58.3%. Poor model performance probably reflects the difficulties associated with modeling the distribution of rare species and the inability of the large-scale habitat variables used in IAGAP models to explain the variation in fish species occurrences. Our results highlight the importance of quantifying the confidence in species distribution model predictions with an independent data set and the need for long-term monitoring to better understand the

  6. Coping and acceptance: the greatest challenge for veterans with intestinal stomas.

    Science.gov (United States)

    Krouse, Robert S; Grant, Marcia; Rawl, Susan M; Mohler, M Jane; Baldwin, Carol M; Coons, Stephen Joel; McCorkle, Ruth; Schmidt, C Max; Ko, Clifford Y

    2009-03-01

    Intestinal stomas (ostomies) create challenges for veterans. The goal of this qualitative analysis was to understand better patients' perspectives regarding their greatest challenge. Ostomates at three Veterans Affairs locations were surveyed using the modified City of Hope Quality of Life-Ostomy questionnaire that contained an open-ended request for respondents to describe their greatest challenge. The response rate was 51% (239 of 467); 68% (163 of 239) completed the open-ended item. Content analysis was performed by an experienced qualitative research team. Coping and acceptance were the most commonly addressed themes. The most frequently expressed issues and advice were related to a need for positive thinking and insight regarding adjustment over time. Coping strategies included the use of humor, recognition of positive changes resulting from the stoma, and normalization of life with an ostomy. Coping and acceptance are common themes described by veterans with an intestinal stoma. Health-care providers can assist veterans by utilizing ostomate self-management strategies, experience, and advice.

  7. The greatest challenges reported by long-term colorectal cancer survivors with stomas.

    Science.gov (United States)

    McMullen, Carmit K; Hornbrook, Mark C; Grant, Marcia; Baldwin, Carol M; Wendel, Christopher S; Mohler, M Jane; Altschuler, Andrea; Ramirez, Michelle; Krouse, Robert S

    2008-04-01

    This paper presents a qualitative analysis of the greatest challenges reported by long-term colorectal cancer survivors with ostomies. Surveys that included an open-ended question about challenges of living with an ostomy were administered at three Kaiser Permanente regions: Northern California, Northwest, and Hawaii. The study was coordinated at the Southern Arizona Veterans Affairs Health Care System in Tucson. The City of Hope Quality of Life Model for Ostomy Patients provided a framework for the study's design, measures, data collection, and data analysis. The study's findings may be generalized broadly to community settings across the United States. Results replicate those of previous research among veterans, California members of the United Ostomy Association, Koreans with ostomies, and colorectal cancer survivors with ostomies residing in the United Kingdom. The greatest challenges reported by 178 colorectal cancer survivors with ostomies confirmed the Institute of Medicine's findings that survivorship is a distinct, chronic phase of cancer care and that cancer's effects are broad and pervasive. The challenges reported by study participants should inform the design, testing and integration of targeted education, early interventions, and ongoing support services for colorectal cancer patients with ostomies.

  8. ADULTS’ LEARNING IN A MULTILEVEL GROUP: DIFFICULTIES AND PROSPECTS

    Directory of Open Access Journals (Sweden)

    Salamatina, I.I.

    2017-12-01

    Full Text Available One of the necessary conditions of modernization of higher education system of the Russian Federation is to increase the level of academic mobility of the teaching community of Russian Universities. To solve this problem in 2014 in the State University of Humanities and Social Studies it was made the decision to organize the biennial English language courses for teachers of non-linguistic specialties, to enhance their level of proficiency. The greatest difficulty in teaching was because of different levels of language proficiency, so the teacher had to develop an effective methodology of teaching English for different levels of students.

  9. Posing Problems to Understand Children's Learning of Fractions

    Science.gov (United States)

    Cheng, Lu Pien

    2013-01-01

    In this study, ways in which problem posing activities aid our understanding of children's learning of addition of unlike fractions and product of proper fractions was examined. In particular, how a simple problem posing activity helps teachers take a second, deeper look at children's understanding of fraction concepts will be discussed. The…

  10. Standard diffusive systems are well-posed linear systems

    NARCIS (Netherlands)

    Matignon, Denis; Zwart, Heiko J.

    2004-01-01

    The class of well-posed linear systems as introduced by Salamon has become a well-understood class of systems, see e.g. the work of Weiss and the book of Staffans. Many partial partial differential equations with boundary control and point observation can be formulated as a well-posed linear system.

  11. Formulas in inverse and ill-posed problems

    CERN Document Server

    Anikonov, Yu E

    1997-01-01

    The Inverse and Ill-Posed Problems Series is a series of monographs publishing postgraduate level information on inverse and ill-posed problems for an international readership of professional scientists and researchers. The series aims to publish works which involve both theory and applications in, e.g., physics, medicine, geophysics, acoustics, electrodynamics, tomography, and ecology.

  12. Turkish Primary School Teachers' Opinions about Problem Posing

    Science.gov (United States)

    Kilic, Cigdem

    2013-01-01

    Problem posing is one of the most important topics in a mathematics education. Through problem posing, students gain mathematical abilities and concepts and teachers can evaluate their students and arrange adequate learning environments. The aim of the present study is to investigate Turkish primary school teachers' opinions about problem posing…

  13. Early Identification of Reading Difficulties

    DEFF Research Database (Denmark)

    Poulsen, Mads; Nielsen, Anne-Mette Veber; Juul, Holger

    2017-01-01

    Early screening for reading difficulties before the onset of instruction is desirable because it allows intervention that is targeted at prevention rather than remediation of reading difficulties. However, early screening may be too inaccurate to effectively allocate resources to those who need...... them. The present study compared the accuracy of early screening before the onset of formal reading instruction with late screening six months into the first year of instruction. The study followed 164 Danish students from the end of Grade 0 to the end of Grade 2. Early screening included measures...... of phonemic awareness, rapid naming, letter knowledge, paired associate learning, and reading. Late screening included only reading. Results indicated that reading measures improved substantially as predictors over the first six months of Grade 1, to the point where late reading measures alone provided...

  14. Face pose tracking using the four-point algorithm

    Science.gov (United States)

    Fung, Ho Yin; Wong, Kin Hong; Yu, Ying Kin; Tsui, Kwan Pang; Kam, Ho Chuen

    2017-06-01

    In this paper, we have developed an algorithm to track the pose of a human face robustly and efficiently. Face pose estimation is very useful in many applications such as building virtual reality systems and creating an alternative input method for the disabled. Firstly, we have modified a face detection toolbox called DLib for the detection of a face in front of a camera. The detected face features are passed to a pose estimation method, known as the four-point algorithm, for pose computation. The theory applied and the technical problems encountered during system development are discussed in the paper. It is demonstrated that the system is able to track the pose of a face in real time using a consumer grade laptop computer.

  15. Real-Time Head Pose Estimation on Mobile Platforms

    Directory of Open Access Journals (Sweden)

    Jianfeng Ren

    2010-06-01

    Full Text Available Many computer vision applications such as augmented reality require head pose estimation. As far as the real-time implementation of head pose estimation on relatively resource limited mobile platforms is concerned, it is required to satisfy real-time constraints while maintaining reasonable head pose estimation accuracy. The introduced head pose estimation approach in this paper is an attempt to meet this objective. The approach consists of the following components: Viola-Jones face detection, color-based face tracking using an online calibration procedure, and head pose estimation using Hu moment features and Fisher linear discriminant. Experimental results running on an actual mobile device are reported exhibiting both the real- time and accuracy aspects of the developed approach.

  16. Pose estimation for mobile robots working on turbine blade

    Energy Technology Data Exchange (ETDEWEB)

    Ma, X.D.; Chen, Q.; Liu, J.J.; Sun, Z.G.; Zhang, W.Z. [Tsinghua Univ., Beijing (China). Key Laboratory for Advanced Materials Processing Technology, Ministry of Education, Dept. of Mechanical Engineering

    2009-03-11

    This paper discussed a features point detection and matching task technique for mobile robots used in wind turbine blade applications. The vision-based scheme used visual information from the robot's surrounding environment to match successive image frames. An improved pose estimation algorithm based on a scale invariant feature transform (SIFT) was developed to consider the characteristics of local images of turbine blades, pose estimation problems, and conditions. The method included a pre-subsampling technique for reducing computation and bidirectional matching for improving precision. A random sample consensus (RANSAC) method was used to estimate the robot's pose. Pose estimation conditions included a wide pose range; the distance between neighbouring blades; and mechanical, electromagnetic, and optical disturbances. An experimental platform was used to demonstrate the validity of the proposed algorithm. 20 refs., 6 figs.

  17. Reducing mortality from childhood pneumonia: The leading priority is also the greatest opportunity

    Directory of Open Access Journals (Sweden)

    Igor Rudan

    2013-06-01

    Full Text Available Pneumonia and diarrhoea have been the leading causes of global child mortality for many decades. The work of Child Health Epidemiology Reference Group (CHERG has been pivotal in raising awareness that the UN's Millennium Development Goal 4 cannot be achieved without increased focus on preventing and treating the two diseases in low– and middle–income countries. Global Action Plan for Pneumonia (GAPP and Diarrhoea Global Action Plan (DGAP groups recently concluded that addressing childhood pneumonia and diarrhoea is not only the leading priority but also the greatest opportunity in global health today: scaling up of existing highly cost–effective interventions could prevent 95% of diarrhoea deaths and 67% of pneumonia deaths in children younger than 5 years by the year 2025. The cost of such effort was estimated at about US$ 6.7 billion.

  18. Person-Independent Head Pose Estimation Using Biased Manifold Embedding

    Directory of Open Access Journals (Sweden)

    Sethuraman Panchanathan

    2008-02-01

    Full Text Available Head pose estimation has been an integral problem in the study of face recognition systems and human-computer interfaces, as part of biometric applications. A fine estimate of the head pose angle is necessary and useful for several face analysis applications. To determine the head pose, face images with varying pose angles can be considered to be lying on a smooth low-dimensional manifold in high-dimensional image feature space. However, when there are face images of multiple individuals with varying pose angles, manifold learning techniques often do not give accurate results. In this work, we propose a framework for a supervised form of manifold learning called Biased Manifold Embedding to obtain improved performance in head pose angle estimation. This framework goes beyond pose estimation, and can be applied to all regression applications. This framework, although formulated for a regression scenario, unifies other supervised approaches to manifold learning that have been proposed so far. Detailed studies of the proposed method are carried out on the FacePix database, which contains 181 face images each of 30 individuals with pose angle variations at a granularity of 1∘. Since biometric applications in the real world may not contain this level of granularity in training data, an analysis of the methodology is performed on sparsely sampled data to validate its effectiveness. We obtained up to 2∘ average pose angle estimation error in the results from our experiments, which matched the best results obtained for head pose estimation using related approaches.

  19. Animated pose templates for modeling and detecting human actions.

    Science.gov (United States)

    Yao, Benjamin Z; Nie, Bruce X; Liu, Zicheng; Zhu, Song-Chun

    2014-03-01

    This paper presents animated pose templates (APTs) for detecting short-term, long-term, and contextual actions from cluttered scenes in videos. Each pose template consists of two components: 1) a shape template with deformable parts represented in an And-node whose appearances are represented by the Histogram of Oriented Gradient (HOG) features, and 2) a motion template specifying the motion of the parts by the Histogram of Optical-Flows (HOF) features. A shape template may have more than one motion template represented by an Or-node. Therefore, each action is defined as a mixture (Or-node) of pose templates in an And-Or tree structure. While this pose template is suitable for detecting short-term action snippets in two to five frames, we extend it in two ways: 1) For long-term actions, we animate the pose templates by adding temporal constraints in a Hidden Markov Model (HMM), and 2) for contextual actions, we treat contextual objects as additional parts of the pose templates and add constraints that encode spatial correlations between parts. To train the model, we manually annotate part locations on several keyframes of each video and cluster them into pose templates using EM. This leaves the unknown parameters for our learning algorithm in two groups: 1) latent variables for the unannotated frames including pose-IDs and part locations, 2) model parameters shared by all training samples such as weights for HOG and HOF features, canonical part locations of each pose, coefficients penalizing pose-transition and part-deformation. To learn these parameters, we introduce a semi-supervised structural SVM algorithm that iterates between two steps: 1) learning (updating) model parameters using labeled data by solving a structural SVM optimization, and 2) imputing missing variables (i.e., detecting actions on unlabeled frames) with parameters learned from the previous step and progressively accepting high-score frames as newly labeled examples. This algorithm belongs to a

  20. Fast human pose estimation using 3D Zernike descriptors

    Science.gov (United States)

    Berjón, Daniel; Morán, Francisco

    2012-03-01

    Markerless video-based human pose estimation algorithms face a high-dimensional problem that is frequently broken down into several lower-dimensional ones by estimating the pose of each limb separately. However, in order to do so they need to reliably locate the torso, for which they typically rely on time coherence and tracking algorithms. Their losing track usually results in catastrophic failure of the process, requiring human intervention and thus precluding their usage in real-time applications. We propose a very fast rough pose estimation scheme based on global shape descriptors built on 3D Zernike moments. Using an articulated model that we configure in many poses, a large database of descriptor/pose pairs can be computed off-line. Thus, the only steps that must be done on-line are the extraction of the descriptors for each input volume and a search against the database to get the most likely poses. While the result of such process is not a fine pose estimation, it can be useful to help more sophisticated algorithms to regain track or make more educated guesses when creating new particles in particle-filter-based tracking schemes. We have achieved a performance of about ten fps on a single computer using a database of about one million entries.

  1. Methods of RVD object pose estimation and experiments

    Science.gov (United States)

    Shang, Yang; He, Yan; Wang, Weihua; Yu, Qifeng

    2007-11-01

    Methods of measuring a RVD (rendezvous and docking) cooperative object's pose from monocular and binocular images respectively are presented. The methods solve the initial values first and optimize the object pose parameters by bundle adjustment. In the disturbance-rejecting binocular method, chosen measurement system parameters of one camera's exterior parameters are modified simultaneously. The methods need three or more cooperative target points to measure the object's pose accurately. Experimental data show that the methods converge quickly and stably, provide accurate results and do not need accurate initial values. Even when the chosen measurement system parameters are subjected to some amount of disturbance, the binocular method manages to provide fairly accurate results.

  2. Ghosts, Troubles, Difficulties, and Challenges

    DEFF Research Database (Denmark)

    Raahauge, Kirsten Marie

    2016-01-01

    not consider ‘ghosts’ or ‘haunting’ as a possible explanation. This causes difficulties when they narrate and contextualise their experience, and typically they present ambiguous narratives and stress their disbelief at and bewilderment with the experiences. Still, as I will try to show in my article......, their bewilderment and the way they use the notions ‘ghost’ and ‘haunting’ point to possible reinterpretations of these notions, so that the narrative mediation shapes not only the experience but also the ways that ‘ghosts’ and ‘haunting’ are reinterpreted in contemporary Denmark....

  3. Sleep Disturbances in Adults With Arthritis: Prevalence, Mediators, and Subgroups at Greatest Risk. Data From the 2007 National Health Interview Survey

    Science.gov (United States)

    LOUIE, GRANT H.; TEKTONIDOU, MARIA G.; CABAN-MARTINEZ, ALBERTO J.; WARD, MICHAEL M.

    2012-01-01

    Objective To examine the prevalence of sleep disturbances in adults with arthritis in a nationally representative sample, mediators of sleep difficulties, and subgroups of individuals with arthritis at greatest risk. Methods Using data on US adults ages ≥18 years participating in the 2007 National Health Interview Survey, we computed the prevalence of 3 measures of sleep disturbance (insomnia, excessive daytime sleepiness, and sleep duration arthritis. We used logistic regression analysis to examine if the association of arthritis and sleep disturbances was independent of sociodemographic characteristics and comorbidities, and to identify potential mediators. We used classification trees to identify subgroups at higher risk. Results The adjusted prevalence of insomnia was higher among adults with arthritis than those without arthritis (23.1% versus 16.4%; P arthritis were more likely than those without arthritis to report insomnia (unadjusted odds ratio 2.92, 95% confidence interval 2.68 –3.17), but adjustment for sociodemographic characteristics and comorbidities attenuated this association. Joint pain and limitation due to pain mediated the association between arthritis and insomnia. Among adults with arthritis, those with depression and anxiety were at highest risk for sleep disturbance. Results for excessive daytime sleepiness and sleep duration arthritis, and is mediated by joint pain and limitation due to pain. Among individuals with arthritis, those with depression and anxiety are at greatest risk. PMID:20890980

  4. Current Global Pricing For Human Papillomavirus Vaccines Brings The Greatest Economic Benefits To Rich Countries.

    Science.gov (United States)

    Herlihy, Niamh; Hutubessy, Raymond; Jit, Mark

    2016-02-01

    Vaccinating females against human papillomavirus (HPV) prior to the debut of sexual activity is an effective way to prevent cervical cancer, yet vaccine uptake in low- and middle-income countries has been hindered by high vaccine prices. We created an economic model to estimate the distribution of the economic surplus-the sum of all health and economic benefits of a vaccine, minus the costs of development, production, and distribution-among different country income groups and manufacturers for a cohort of twelve-year-old females in 2012. We found that manufacturers may have received economic returns worth five times their original investment in HPV vaccine development. High-income countries gained the greatest economic surplus of any income category, realizing over five times more economic value per vaccinated female than low-income countries did. Subsidizing vaccine prices in low- and middle-income countries could both reduce financial barriers to vaccine adoption and still allow high-income countries to retain their economic surpluses and manufacturers to retain their profits. Project HOPE—The People-to-People Health Foundation, Inc.

  5. MreB filaments align along greatest principal membrane curvature to orient cell wall synthesis

    Science.gov (United States)

    Szwedziak, Piotr; Wong, Felix; Schaefer, Kaitlin; Izoré, Thierry; Renner, Lars D; Holmes, Matthew J; Sun, Yingjie; Bisson-Filho, Alexandre W; Walker, Suzanne; Amir, Ariel; Löwe, Jan

    2018-01-01

    MreB is essential for rod shape in many bacteria. Membrane-associated MreB filaments move around the rod circumference, helping to insert cell wall in the radial direction to reinforce rod shape. To understand how oriented MreB motion arises, we altered the shape of Bacillus subtilis. MreB motion is isotropic in round cells, and orientation is restored when rod shape is externally imposed. Stationary filaments orient within protoplasts, and purified MreB tubulates liposomes in vitro, orienting within tubes. Together, this demonstrates MreB orients along the greatest principal membrane curvature, a conclusion supported with biophysical modeling. We observed that spherical cells regenerate into rods in a local, self-reinforcing manner: rapidly propagating rods emerge from small bulges, exhibiting oriented MreB motion. We propose that the coupling of MreB filament alignment to shape-reinforcing peptidoglycan synthesis creates a locally-acting, self-organizing mechanism allowing the rapid establishment and stable maintenance of emergent rod shape. PMID:29469806

  6. Covering women's greatest health fear: breast cancer information in consumer magazines.

    Science.gov (United States)

    Walsh-Childers, Kim; Edwards, Heather; Grobmyer, Stephen

    2011-04-01

    Women identify consumer magazines as a key source of information on many health topics, including breast cancer, which continues to rank as women's greatest personal health fear. This study examined the comprehensiveness and accuracy of breast cancer information provided in 555 articles published in 17 consumer magazines from 2002 through 2007. Accuracy of information was determined for 33 key breast cancer facts identified by an expert panel as important information for women to know. The results show that only 7 of 33 key facts were mentioned in at least 5% of the articles. These facts all dealt with breast cancer risk factors, screening, and detection; none of the key facts related to treatment or outcomes appeared in at least 5% of the articles. Other topics (not key facts) mentioned centered around controllable risk factors, support for breast cancer patients, and chemotherapy treatment. The majority of mentions of key facts were coded as fully accurate, although as much as 44% of mentions of some topics (the link between hormone replacement therapy and breast cancer) were coded as inaccurate or only partially accurate. The magazines were most likely to emphasize family history of breast cancer or genetic characteristics as risk factors for breast cancers; family history was twice as likely to be discussed as increasing age, which is in fact the most important risk factor for breast cancer other than being female. Magazine coverage may contribute to women's inaccurate perceptions of their breast cancer risk.

  7. ESPRIT: Exercise Sensing and Pose Recovery Inference Tool, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose to develop ESPRIT: an Exercise Sensing and Pose Recovery Inference Tool, in support of NASA's effort in developing crew exercise technologies for...

  8. Health Issues: Do Cell Phones Pose a Health Hazard?

    Science.gov (United States)

    ... Procedures Home, Business, and Entertainment Products Cell Phones Health Issues Share Tweet Linkedin Pin it More sharing ... it Email Print Do cell phones pose a health hazard? Many people are concerned that cell phone ...

  9. Mathematical Thinking and Creativity through Mathematical Problem Posing and Solving

    Directory of Open Access Journals (Sweden)

    María F. Ayllón

    2016-04-01

    Full Text Available This work shows the relationship between the development of mathematical thinking and creativity with mathematical problem posing and solving. Creativity and mathematics are disciplines that do not usually appear together. Both concepts constitute complex processes sharing elements, such as fluency (number of ideas, flexibility (range of ideas, novelty (unique idea and elaboration (idea development. These factors contribute, among others, to the fact that schoolchildren are competent in mathematics. The problem solving and posing are a very powerful evaluation tool that shows the mathematical reasoning and creative level of a person. Creativity is part of the mathematics education and is a necessary ingredient to perform mathematical assignments. This contribution presents some important research works about problem posing and solving related to the development of mathematical knowledge and creativity. To that end, it is based on various beliefs reflected in the literature with respect to notions of creativity, problem solving and posing.

  10. Pose estimation of industrial objects towards robot operation

    Science.gov (United States)

    Niu, Jie; Zhou, Fuqiang; Tan, Haishu; Cao, Yu

    2017-10-01

    With the advantages of wide range, non-contact and high flexibility, the visual estimation technology of target pose has been widely applied in modern industry, robot guidance and other engineering practices. However, due to the influence of complicated industrial environment, outside interference factors, lack of object characteristics, restrictions of camera and other limitations, the visual estimation technology of target pose is still faced with many challenges. Focusing on the above problems, a pose estimation method of the industrial objects is developed based on 3D models of targets. By matching the extracted shape characteristics of objects with the priori 3D model database of targets, the method realizes the recognition of target. Thus a pose estimation of objects can be determined based on the monocular vision measuring model. The experimental results show that this method can be implemented to estimate the position of rigid objects based on poor images information, and provides guiding basis for the operation of the industrial robot.

  11. Inverse and Ill-posed Problems Theory and Applications

    CERN Document Server

    Kabanikhin, S I

    2011-01-01

    The text demonstrates the methods for proving the existence (if et all) and finding of inverse and ill-posed problems solutions in linear algebra, integral and operator equations, integral geometry, spectral inverse problems, and inverse scattering problems. It is given comprehensive background material for linear ill-posed problems and for coefficient inverse problems for hyperbolic, parabolic, and elliptic equations. A lot of examples for inverse problems from physics, geophysics, biology, medicine, and other areas of application of mathematics are included.

  12. Contactless and pose invariant biometric identification using hand surface.

    Science.gov (United States)

    Kanhangad, Vivek; Kumar, Ajay; Zhang, David

    2011-05-01

    This paper presents a novel approach for hand matching that achieves significantly improved performance even in the presence of large hand pose variations. The proposed method utilizes a 3-D digitizer to simultaneously acquire intensity and range images of the user's hand presented to the system in an arbitrary pose. The approach involves determination of the orientation of the hand in 3-D space followed by pose normalization of the acquired 3-D and 2-D hand images. Multimodal (2-D as well as 3-D) palmprint and hand geometry features, which are simultaneously extracted from the user's pose normalized textured 3-D hand, are used for matching. Individual matching scores are then combined using a new dynamic fusion strategy. Our experimental results on the database of 114 subjects with significant pose variations yielded encouraging results. Consistent (across various hand features considered) performance improvement achieved with the pose correction demonstrates the usefulness of the proposed approach for hand based biometric systems with unconstrained and contact-free imaging. The experimental results also suggest that the dynamic fusion approach employed in this work helps to achieve performance improvement of 60% (in terms of EER) over the case when matching scores are combined using the weighted sum rule.

  13. Perspective projection for variance pose face recognition from camera calibration

    Science.gov (United States)

    Fakhir, M. M.; Woo, W. L.; Chambers, J. A.; Dlay, S. S.

    2016-04-01

    Variance pose is an important research topic in face recognition. The alteration of distance parameters across variance pose face features is a challenging. We provide a solution for this problem using perspective projection for variance pose face recognition. Our method infers intrinsic camera parameters of the image which enable the projection of the image plane into 3D. After this, face box tracking and centre of eyes detection can be identified using our novel technique to verify the virtual face feature measurements. The coordinate system of the perspective projection for face tracking allows the holistic dimensions for the face to be fixed in different orientations. The training of frontal images and the rest of the poses on FERET database determine the distance from the centre of eyes to the corner of box face. The recognition system compares the gallery of images against different poses. The system initially utilises information on position of both eyes then focuses principally on closest eye in order to gather data with greater reliability. Differentiation between the distances and position of the right and left eyes is a unique feature of our work with our algorithm outperforming other state of the art algorithms thus enabling stable measurement in variance pose for each individual.

  14. Robust head pose estimation via supervised manifold learning.

    Science.gov (United States)

    Wang, Chao; Song, Xubo

    2014-05-01

    Head poses can be automatically estimated using manifold learning algorithms, with the assumption that with the pose being the only variable, the face images should lie in a smooth and low-dimensional manifold. However, this estimation approach is challenging due to other appearance variations related to identity, head location in image, background clutter, facial expression, and illumination. To address the problem, we propose to incorporate supervised information (pose angles of training samples) into the process of manifold learning. The process has three stages: neighborhood construction, graph weight computation and projection learning. For the first two stages, we redefine inter-point distance for neighborhood construction as well as graph weight by constraining them with the pose angle information. For Stage 3, we present a supervised neighborhood-based linear feature transformation algorithm to keep the data points with similar pose angles close together but the data points with dissimilar pose angles far apart. The experimental results show that our method has higher estimation accuracy than the other state-of-art algorithms and is robust to identity and illumination variations. Copyright © 2014 Elsevier Ltd. All rights reserved.

  15. Reef fishes in biodiversity hotspots are at greatest risk from loss of coral species.

    Directory of Open Access Journals (Sweden)

    Sally J Holbrook

    Full Text Available Coral reef ecosystems are under a variety of threats from global change and anthropogenic disturbances that are reducing the number and type of coral species on reefs. Coral reefs support upwards of one third of all marine species of fish, so the loss of coral habitat may have substantial consequences to local fish diversity. We posit that the effects of habitat degradation will be most severe in coral regions with highest biodiversity of fishes due to greater specialization by fishes for particular coral habitats. Our novel approach to this important but untested hypothesis was to conduct the same field experiment at three geographic locations across the Indo-Pacific biodiversity gradient (Papua New Guinea; Great Barrier Reef, Australia; French Polynesia. Specifically, we experimentally explored whether the response of local fish communities to identical changes in diversity of habitat-providing corals was independent of the size of the regional species pool of fishes. We found that the proportional reduction (sensitivity in fish biodiversity to loss of coral diversity was greater for regions with larger background species pools, reflecting variation in the degree of habitat specialization of fishes across the Indo-Pacific diversity gradient. This result implies that habitat-associated fish in diversity hotspots are at greater risk of local extinction to a given loss of habitat diversity compared to regions with lower species richness. This mechanism, related to the positive relationship between habitat specialization and regional biodiversity, and the elevated extinction risk this poses for biodiversity hotspots, may apply to species in other types of ecosystems.

  16. Reef fishes in biodiversity hotspots are at greatest risk from loss of coral species.

    Science.gov (United States)

    Holbrook, Sally J; Schmitt, Russell J; Messmer, Vanessa; Brooks, Andrew J; Srinivasan, Maya; Munday, Philip L; Jones, Geoffrey P

    2015-01-01

    Coral reef ecosystems are under a variety of threats from global change and anthropogenic disturbances that are reducing the number and type of coral species on reefs. Coral reefs support upwards of one third of all marine species of fish, so the loss of coral habitat may have substantial consequences to local fish diversity. We posit that the effects of habitat degradation will be most severe in coral regions with highest biodiversity of fishes due to greater specialization by fishes for particular coral habitats. Our novel approach to this important but untested hypothesis was to conduct the same field experiment at three geographic locations across the Indo-Pacific biodiversity gradient (Papua New Guinea; Great Barrier Reef, Australia; French Polynesia). Specifically, we experimentally explored whether the response of local fish communities to identical changes in diversity of habitat-providing corals was independent of the size of the regional species pool of fishes. We found that the proportional reduction (sensitivity) in fish biodiversity to loss of coral diversity was greater for regions with larger background species pools, reflecting variation in the degree of habitat specialization of fishes across the Indo-Pacific diversity gradient. This result implies that habitat-associated fish in diversity hotspots are at greater risk of local extinction to a given loss of habitat diversity compared to regions with lower species richness. This mechanism, related to the positive relationship between habitat specialization and regional biodiversity, and the elevated extinction risk this poses for biodiversity hotspots, may apply to species in other types of ecosystems.

  17. Multi-task pose-invariant face recognition.

    Science.gov (United States)

    Ding, Changxing; Xu, Chang; Tao, Dacheng

    2015-03-01

    Face images captured in unconstrained environments usually contain significant pose variation, which dramatically degrades the performance of algorithms designed to recognize frontal faces. This paper proposes a novel face identification framework capable of handling the full range of pose variations within ±90° of yaw. The proposed framework first transforms the original pose-invariant face recognition problem into a partial frontal face recognition problem. A robust patch-based face representation scheme is then developed to represent the synthesized partial frontal faces. For each patch, a transformation dictionary is learnt under the proposed multi-task learning scheme. The transformation dictionary transforms the features of different poses into a discriminative subspace. Finally, face matching is performed at patch level rather than at the holistic level. Extensive and systematic experimentation on FERET, CMU-PIE, and Multi-PIE databases shows that the proposed method consistently outperforms single-task-based baselines as well as state-of-the-art methods for the pose problem. We further extend the proposed algorithm for the unconstrained face verification problem and achieve top-level performance on the challenging LFW data set.

  18. Students’ Mathematical Creative Thinking through Problem Posing Learning

    Science.gov (United States)

    Ulfah, U.; Prabawanto, S.; Jupri, A.

    2017-09-01

    The research aims to investigate the differences in enhancement of students’ mathematical creative thinking ability of those who received problem posing approach assisted by manipulative media and students who received problem posing approach without manipulative media. This study was a quasi experimental research with non-equivalent control group design. Population of this research was third-grade students of a primary school in Bandung city in 2016/2017 academic year. Sample of this research was two classes as experiment class and control class. The instrument used is a test of mathematical creative thinking ability. Based on the results of the research, it is known that the enhancement of the students’ mathematical creative thinking ability of those who received problem posing approach with manipulative media aid is higher than the ability of those who received problem posing approach without manipulative media aid. Students who get learning problem posing learning accustomed in arranging mathematical sentence become matter of story so it can facilitate students to comprehend about story

  19. Temporal subtraction of chest radiographs compensating pose differences

    Science.gov (United States)

    von Berg, Jens; Dworzak, Jalda; Klinder, Tobias; Manke, Dirk; Kreth, Adrian; Lamecker, Hans; Zachow, Stefan; Lorenz, Cristian

    2011-03-01

    Temporal subtraction techniques using 2D image registration improve the detectability of interval changes from chest radiographs. Although such methods are well known for some time they are not widely used in radiologic practice. The reason is the occurrence of strong pose differences between two acquisitions with a time interval of months to years in between. Such strong perspective differences occur in a reasonable number of cases. They cannot be compensated by available image registration methods and thus mask interval changes to be undetectable. In this paper a method is proposed to estimate a 3D pose difference by the adaptation of a 3D rib cage model to both projections. The difference between both is then compensated for, thus producing a subtraction image with virtually no change in pose. The method generally assumes that no 3D image data is available from the patient. The accuracy of pose estimation is validated with chest phantom images acquired under controlled geometric conditions. A subtle interval change simulated by a piece of plastic foam attached to the phantom becomes visible in subtraction images generated with this technique even at strong angular pose differences like an anterior-posterior inclination of 13 degrees.

  20. Preparatory power posing affects nonverbal presence and job interview performance.

    Science.gov (United States)

    Cuddy, Amy J C; Wilmuth, Caroline A; Yap, Andy J; Carney, Dana R

    2015-07-01

    The authors tested whether engaging in expansive (vs. contractive) "power poses" before a stressful job interview--preparatory power posing--would enhance performance during the interview. Participants adopted high-power (i.e., expansive, open) poses or low-power (i.e., contractive, closed) poses, and then prepared and delivered a speech to 2 evaluators as part of a mock job interview. All interview speeches were videotaped and coded for overall performance and hireability and for 2 potential mediators: verbal content (e.g., structure, content) and nonverbal presence (e.g., captivating, enthusiastic). As predicted, those who prepared for the job interview with high- (vs. low-) power poses performed better and were more likely to be chosen for hire; this relation was mediated by nonverbal presence, but not by verbal content. Although previous research has focused on how a nonverbal behavior that is enacted during interactions and observed by perceivers affects how those perceivers evaluate and respond to the actor, this experiment focused on how a nonverbal behavior that is enacted before the interaction and unobserved by perceivers affects the actor's performance, which, in turn, affects how perceivers evaluate and respond to the actor. This experiment reveals a theoretically novel and practically informative result that demonstrates the causal relation between preparatory nonverbal behavior and subsequent performance and outcomes. (c) 2015 APA, all rights reserved).

  1. Pose estimation for augmented reality applications using genetic algorithm.

    Science.gov (United States)

    Yu, Ying Kin; Wong, Kin Hong; Chang, Michael Ming Yuen

    2005-12-01

    This paper describes a genetic algorithm that tackles the pose-estimation problem in computer vision. Our genetic algorithm can find the rotation and translation of an object accurately when the three-dimensional structure of the object is given. In our implementation, each chromosome encodes both the pose and the indexes to the selected point features of the object. Instead of only searching for the pose as in the existing work, our algorithm, at the same time, searches for a set containing the most reliable feature points in the process. This mismatch filtering strategy successfully makes the algorithm more robust under the presence of point mismatches and outliers in the images. Our algorithm has been tested with both synthetic and real data with good results. The accuracy of the recovered pose is compared to the existing algorithms. Our approach outperformed the Lowe's method and the other two genetic algorithms under the presence of point mismatches and outliers. In addition, it has been used to estimate the pose of a real object. It is shown that the proposed method is applicable to augmented reality applications.

  2. Pose-Invariant Face Recognition via RGB-D Images.

    Science.gov (United States)

    Sang, Gaoli; Li, Jing; Zhao, Qijun

    2016-01-01

    Three-dimensional (3D) face models can intrinsically handle large pose face recognition problem. In this paper, we propose a novel pose-invariant face recognition method via RGB-D images. By employing depth, our method is able to handle self-occlusion and deformation, both of which are challenging problems in two-dimensional (2D) face recognition. Texture images in the gallery can be rendered to the same view as the probe via depth. Meanwhile, depth is also used for similarity measure via frontalization and symmetric filling. Finally, both texture and depth contribute to the final identity estimation. Experiments on Bosphorus, CurtinFaces, Eurecom, and Kiwi databases demonstrate that the additional depth information has improved the performance of face recognition with large pose variations and under even more challenging conditions.

  3. Access to care for children with emotional/behavioral difficulties.

    Science.gov (United States)

    Henning-Smith, Carrie; Alang, Sirry

    2016-06-01

    Emotional/behavioral difficulties (EBDs) are increasingly diagnosed in children, constituting some of the most common chronic childhood conditions. Left untreated, EBDs pose long-term individual and population-level consequences. There is a growing evidence of disparities in EBD prevalence by various demographic characteristics. This article builds on this research by examining disparities in access to medical care for children with EBD. From 2008 to 2011, using data from the US National Health Interview Survey (N = 31,631) on sample children aged 4-17, we investigate (1) whether having EBD affects access to care (modeled as delayed care due to cost and difficulty making an appointment) and (2) the role demographic characteristics, health insurance coverage, and frequency of service use play in access to care for children with EBD. Results indicate that children with EBD experience issues in accessing care at more than twice the rate of children without EBD, even though they are less likely to be uninsured than their counterparts without EBD. In multivariable models, children with EBD are still more likely to experience delayed care due to cost and difficulty making a timely appointment, even after adjusting for frequency of health service use, insurance coverage, and demographic characteristics. © The Author(s) 2015.

  4. [Central diabetes insipidus: diagnostic difficulties].

    Science.gov (United States)

    Matoussi, N; Aissa, K; Fitouri, Z; Hajji, M; Makni, S; Bellagha, I; Ben Becher, S

    2008-06-01

    Central diabetes insipidus is rare in children. Characteristic features include polyuria and polydipsia due to arginine vasopressin deficiency. The differential diagnosis of polyuric states may be difficult. Etiologic diagnosis of central diabetes insipidus may be an equally difficult task. To specify the difficulties encountered in the diagnosis of central diabetes insipidus and to point out features of the etiologic work-up and of long-term follow-up of children with idiopathic central diabetes insipidus. A retrospective study of 12 children admitted with a polyuria/polydipsia syndrome to the pediatric - consultation and emergency unit of the children's hospital of Tunis between 1988 and 2005. Children with acquired nephrogenic central diabetes insipidus were excluded. Fourteen-hour fluid restriction test and/or desmopressin test were used without plasma vasopressin measurement. Eight patients were classified as having central diabetes insipidus, which was severe in seven children and partial in one girl. One patient was classified as having primary polydipsia. The diagnosis remains unclear in three patients. The etiological work-up in eight patients with central diabetes insipidus enabled the identification of Langerhan's-cell histiocytosis in two patients and neurosurgical trauma in one. The cause was considered idiopathic in five patients. The median follow-up of the five patients with idiopathic central diabetes insipidus was five years two months plus or minus six years seven months (range five months, 14.5 years). During this follow-up, neither brain magnetic resonance imaging scans findings nor anterior pituitary function have changed. Fluid restriction and desmopressin tests did not enable an accurate distinction between partial diabetes insipidus and primary polydipsia. Regular surveillance is warranted in patients with idiopathic central diabetes insipidus to identify potential etiologies.

  5. Pose-invariant face recognition using Markov random fields.

    Science.gov (United States)

    Ho, Huy Tho; Chellappa, Rama

    2013-04-01

    One of the key challenges for current face recognition techniques is how to handle pose variations between the probe and gallery face images. In this paper, we present a method for reconstructing the virtual frontal view from a given nonfrontal face image using Markov random fields (MRFs) and an efficient variant of the belief propagation algorithm. In the proposed approach, the input face image is divided into a grid of overlapping patches, and a globally optimal set of local warps is estimated to synthesize the patches at the frontal view. A set of possible warps for each patch is obtained by aligning it with images from a training database of frontal faces. The alignments are performed efficiently in the Fourier domain using an extension of the Lucas-Kanade algorithm that can handle illumination variations. The problem of finding the optimal warps is then formulated as a discrete labeling problem using an MRF. The reconstructed frontal face image can then be used with any face recognition technique. The two main advantages of our method are that it does not require manually selected facial landmarks or head pose estimation. In order to improve the performance of our pose normalization method in face recognition, we also present an algorithm for classifying whether a given face image is at a frontal or nonfrontal pose. Experimental results on different datasets are presented to demonstrate the effectiveness of the proposed approach.

  6. Introduced organisms pose the most significant threat to the ...

    African Journals Online (AJOL)

    spamer

    Introduced organisms pose the most significant threat to the conservation status of oceanic islands (e.g.. Williamson 1996). Subantarctic Prince Edward Island, the smaller of the two islands in the Prince Edward. Island group, has few introduced organisms; it is cur- rently known to support only three introduced animals.

  7. Full Body Pose Estimation During Occlusion using Multiple Cameras

    DEFF Research Database (Denmark)

    Fihl, Preben; Cosar, Serhan

    people is a very challenging problem for methods based on pictorials structure as for any other monocular pose estimation method. In this report we present work on a multi-view approach based on pictorial structures that integrate low level information from multiple calibrated cameras to improve the 2D...

  8. Spontaneous and posed facial expression in Parkinson's disease.

    Science.gov (United States)

    Smith, M C; Smith, M K; Ellgring, H

    1996-09-01

    Spontaneous and posed emotional facial expressions in individuals with Parkinson's disease (PD, n = 12) were compared with those of healthy age-matched controls (n = 12). The intensity and amount of facial expression in PD patients were expected to be reduced for spontaneous but not posed expressions. Emotional stimuli were video clips selected from films, 2-5 min in duration, designed to elicit feelings of happiness, sadness, fear, disgust, or anger. Facial movements were coded using Ekman and Friesen's (1978) Facial Action Coding System (FACS). In addition, participants rated their emotional experience on 9-point Likert scales. The PD group showed significantly less overall facial reactivity than did controls when viewing the films. The predicted Group X Condition (spontaneous vs. posed) interaction effect on smile intensity was found when PD participants with more severe disease were compared with those with milder disease and with controls. In contrast, ratings of emotional experience were similar for both groups. Depression was positively associated with emotion rating but not with measures of facial activity. Spontaneous facial expression appears to be selectively affected in PD, whereas posed expression and emotional experience remain relatively intact.

  9. Enhancing Students' Communication Skills through Problem Posing and Presentation

    Science.gov (United States)

    Sugito; E. S., Sri Mulyani; Hartono; Supartono

    2017-01-01

    This study was to explore how enhance communication skill through problem posing and presentation method. The subjects of this research were the seven grade students Junior High School, including 20 male and 14 female. This research was conducted in two cycles and each cycle consisted of four steps, they were: planning, action, observation, and…

  10. Binary classification posed as a quadratically constrained quadratic ...

    Indian Academy of Sciences (India)

    Binary classification is posed as a quadratically constrained quadratic problem and solved using the proposed method. Each class in the binary classification problem is modeled as a multidimensional ellipsoid to forma quadratic constraint in the problem. Particle swarms help in determining the optimal hyperplane or ...

  11. Mathematical Thinking and Creativity through Mathematical Problem Posing and Solving

    Science.gov (United States)

    Ayllón, María F.; Gómez, Isabel A.; Ballesta-Claver, Julio

    2016-01-01

    This work shows the relationship between the development of mathematical thinking and creativity with mathematical problem posing and solving. Creativity and mathematics are disciplines that do not usually appear together. Both concepts constitute complex processes sharing elements, such as fluency (number of ideas), flexibility (range of ideas),…

  12. Developing teachers' subject didactic competence through problem posing

    Czech Academy of Sciences Publication Activity Database

    Tichá, Marie; Hošpesová, A.

    2013-01-01

    Roč. 83, č. 1 (2013), s. 133-143 ISSN 0013-1954 Institutional support: RVO:67985840 Keywords : professional development * primary school teachers * problem posing Subject RIV: AM - Education Impact factor: 0.639, year: 2013 http://link.springer.com/article/10.1007%2Fs10649-012-9455-1

  13. The relative pose estimation of aircraft based on contour model

    Science.gov (United States)

    Fu, Tai; Sun, Xiangyi

    2017-02-01

    This paper proposes a relative pose estimation approach based on object contour model. The first step is to obtain a two-dimensional (2D) projection of three-dimensional (3D)-model-based target, which will be divided into 40 forms by clustering and LDA analysis. Then we proceed by extracting the target contour in each image and computing their Pseudo-Zernike Moments (PZM), thus a model library is constructed in an offline mode. Next, we spot a projection contour that resembles the target silhouette most in the present image from the model library with reference of PZM; then similarity transformation parameters are generated as the shape context is applied to match the silhouette sampling location, from which the identification parameters of target can be further derived. Identification parameters are converted to relative pose parameters, in the premise that these values are the initial result calculated via iterative refinement algorithm, as the relative pose parameter is in the neighborhood of actual ones. At last, Distance Image Iterative Least Squares (DI-ILS) is employed to acquire the ultimate relative pose parameters.

  14. Optical neural network system for pose determination of spinning satellites

    Science.gov (United States)

    Lee, Andrew; Casasent, David

    1990-01-01

    An optical neural network architecture and algorithm based on a Hopfield optimization network are presented for multitarget tracking. This tracker utilizes a neuron for every possible target track, and a quadratic energy function of neural activities which is minimized using gradient descent neural evolution. The neural net tracker is demonstrated as part of a system for determining position and orientation (pose) of spinning satellites with respect to a robotic spacecraft. The input to the system is time sequence video from a single camera. Novelty detection and filtering are utilized to locate and segment novel regions from the input images. The neural net multitarget tracker determines the correspondences (or tracks) of the novel regions as a function of time, and hence the paths of object (satellite) parts. The path traced out by a given part or region is approximately elliptical in image space, and the position, shape and orientation of the ellipse are functions of the satellite geometry and its pose. Having a geometric model of the satellite, and the elliptical path of a part in image space, the three-dimensional pose of the satellite is determined. Digital simulation results using this algorithm are presented for various satellite poses and lighting conditions.

  15. 3D Facial Landmarking under Expression, Pose, and Occlusion Variations

    NARCIS (Netherlands)

    H. Dibeklioğ lu; A.A. Salah (Albert Ali); L. Akarun

    2008-01-01

    htmlabstractAutomatic localization of 3D facial features is important for face recognition, tracking, modeling and expression analysis. Methods developed for 2D images were shown to have problems working across databases acquired with different illumination conditions. Expression variations, pose

  16. POSING THE HISTORICAL JESUS QUESTION AND THE GOAL OF ...

    African Journals Online (AJOL)

    mycl

    ... study recommended that. African scholars be allowed to develop and pose the Historical Jesus ... he is seen as the starting point for modern critical study of Jesus. (Burer). ... African anthropology and culture and the data of revelation, and how this theology ... Man” from two perspectives: that of a biblical culture in the first.

  17. Zebra Mussels Pose a Threat to Virginia's Waters

    OpenAIRE

    Helfrich, Louis A. (Louis Anthony), 1942-; Weigmann, Diana L.; Speenburgh, Renee M.; Neves, Richard J.; Kitchel, Lisie; Bruenderman, Sue A., 1962-

    2005-01-01

    Provides an brief introduction to the invasion of the zebra mussel into American waters, explains the economic consequences they pose, and discusses if Virginia will inherit the problem, what the public can do to help, the general lifecycle of the zebra mussel and if they can be controlled, and who is working on the zebra mussel problem.

  18. Effects of pose and image resolution on automatic face recognition

    NARCIS (Netherlands)

    Mahmood, Zahid; Ali, Tauseef; Khan, Samee U.

    The popularity of face recognition systems have increased due to their use in widespread applications. Driven by the enormous number of potential application domains, several algorithms have been proposed for face recognition. Face pose and image resolutions are among the two important factors that

  19. DIFFICULTIeS OF TOTAL HIP REPLACEMENT IN PATIENTS WITH ANKYLOSING SPONDYLITIS (case report

    Directory of Open Access Journals (Sweden)

    R. M. Tikhilov

    2016-01-01

    Full Text Available A distinctive feature of patients with ankylosing spondylitis is the formation of hip ankylosis in an extremely unfavorable functional position combined with upset of sagittal balance of the body along with a thoracolumbar kyphosis. Treatment of these patients poses considerable technical difficulties and is often associated with complications. The authors report a clinical case of a female 40 years old patient with confirmed rhizomelic spondylitis. The patient mainly complained of fixed malposition of the right lower extremity (hip ankylosis in extreme 1450 flexion and 1500 abduction combined with a severe fixed spine deformity (thoracic kyphosis 920, lumbar lordosis 170. Considering significant sagittal balance disorder it was decided to go for a two-stage procedure. Total hip arthroplasty of the right joint was performed at the first stage. At the second stage the authors corrected thoracolumbar spinal deformity by Th12 (type PSO 4 and L2 (type PSO 3 wedge resections and converging resected vertebral bodies by a multilevel fixation system with transpedicular support elements. The interval between the stages was 11 months. Two-stage treatment of this patient al-lowed to avoid adverse postoperative complications and to achieve a significant functional improvement in one year after treatment started. The sum of points before and after the treat-ment amounted respectively to 46 and 79 on Harris Hip Score, 17 and 38 points on Oxford Hip Score (OHS. To summarize, comprehensive treatment with planning of all subsequent steps prior to hip replacement is the method of choice for avoidance of postoperative complications in patients with ankylosing spondylitis accompanied by a significant upset of sagittal balance.

  20. Pose tracking for augmented reality applications in outdoor archaeological sites

    Science.gov (United States)

    Younes, Georges; Asmar, Daniel; Elhajj, Imad; Al-Harithy, Howayda

    2017-01-01

    In recent years, agencies around the world have invested huge amounts of effort toward digitizing many aspects of the world's cultural heritage. Of particular importance is the digitization of outdoor archaeological sites. In the spirit of valorization of this digital information, many groups have developed virtual or augmented reality (AR) computer applications themed around a particular archaeological object. The problem of pose tracking in outdoor AR applications is addressed. Different positional systems are analyzed, resulting in the selection of a monocular camera-based user tracker. The limitations that challenge this technique from map generation, scale, anchoring, to lighting conditions are analyzed and systematically addressed. Finally, as a case study, our pose tracking system is implemented within an AR experience in the Byblos Roman theater in Lebanon.

  1. Pose Estimation of Interacting People using Pictorial Structures

    DEFF Research Database (Denmark)

    Fihl, Preben; Moeslund, Thomas B.

    2010-01-01

    Pose estimation of people have had great progress in recent years but so far research has dealt with single persons. In this paper we address some of the challenges that arise when doing pose estimation of interacting people. We build on the pictorial structures framework and make important...... contributions by combining color-based appearance and edge information using a measure of the local quality of the appearance feature. In this way we not only combine the two types of features but dynamically find the optimal weighting of them. We further enable the method to handle occlusions by searching...... a foreground mask for possible occluded body parts and then applying extra strong kinematic constraints to find the true occluded body parts. The effect of applying our two contributions are show through both qualitative and quantitative tests and show a clear improvement on the ability to correctly localize...

  2. Strategic management of health risks posed by buried transuranic wastes

    International Nuclear Information System (INIS)

    Jump, R.A.

    1994-01-01

    A strategy is presented for reducing health risks at sites contaminated with buried transuranic (TRU) wastes by first taking measures to immobilize the contaminants until the second step, final action, becomes cost-effective and poses less risk to the remediation workers. The first step of this strategy does not preclude further action if it is warranted and is in harmony with environmental laws and regulations

  3. Sensing Strategies for Disambiguating among Multiple Objects in Known Poses.

    Science.gov (United States)

    1985-08-01

    ELEMENT. PROIECT. TASK Artificial Inteligence Laboratory AE OKUI UBR 545 Technology Square Cambridge, MA 021.39 11. CONTROLLING OFFICE NAME AND ADDRESS 12...AD-Ali65 912 SENSING STRATEGIES FOR DISAMBIGURTING MONG MULTIPLE 1/1 OBJECTS IN KNOWN POSES(U) MASSACHUSETTS INST OF TECH CAMBRIDGE ARTIFICIAL ...or Dist Special 1 ’ MASSACHUSETTS INSTITUTE OF TECHNOLOGY ARTIFICIAL INTELLIGENCE LABORATORY A. I. Memo 855 August, 1985 Sensing Strategies for

  4. Solution of linear ill-posed problems using overcomplete dictionaries

    OpenAIRE

    Pensky, Marianna

    2016-01-01

    In the present paper we consider application of overcomplete dictionaries to solution of general ill-posed linear inverse problems. Construction of an adaptive optimal solution for such problems usually relies either on a singular value decomposition or representation of the solution via an orthonormal basis. The shortcoming of both approaches lies in the fact that, in many situations, neither the eigenbasis of the linear operator nor a standard orthonormal basis constitutes an appropriate co...

  5. Mining Key Skeleton Poses with Latent SVM for Action Recognition

    Directory of Open Access Journals (Sweden)

    Xiaoqiang Li

    2017-01-01

    Full Text Available Human action recognition based on 3D skeleton has become an active research field in recent years with the recently developed commodity depth sensors. Most published methods analyze an entire 3D depth data, construct mid-level part representations, or use trajectory descriptor of spatial-temporal interest point for recognizing human activities. Unlike previous work, a novel and simple action representation is proposed in this paper which models the action as a sequence of inconsecutive and discriminative skeleton poses, named as key skeleton poses. The pairwise relative positions of skeleton joints are used as feature of the skeleton poses which are mined with the aid of the latent support vector machine (latent SVM. The advantage of our method is resisting against intraclass variation such as noise and large nonlinear temporal deformation of human action. We evaluate the proposed approach on three benchmark action datasets captured by Kinect devices: MSR Action 3D dataset, UTKinect Action dataset, and Florence 3D Action dataset. The detailed experimental results demonstrate that the proposed approach achieves superior performance to the state-of-the-art skeleton-based action recognition methods.

  6. Teaching Human Poses Interactively to a Social Robot

    Science.gov (United States)

    Gonzalez-Pacheco, Victor; Malfaz, Maria; Fernandez, Fernando; Salichs, Miguel A.

    2013-01-01

    The main activity of social robots is to interact with people. In order to do that, the robot must be able to understand what the user is saying or doing. Typically, this capability consists of pre-programmed behaviors or is acquired through controlled learning processes, which are executed before the social interaction begins. This paper presents a software architecture that enables a robot to learn poses in a similar way as people do. That is, hearing its teacher's explanations and acquiring new knowledge in real time. The architecture leans on two main components: an RGB-D (Red-, Green-, Blue- Depth) -based visual system, which gathers the user examples, and an Automatic Speech Recognition (ASR) system, which processes the speech describing those examples. The robot is able to naturally learn the poses the teacher is showing to it by maintaining a natural interaction with the teacher. We evaluate our system with 24 users who teach the robot a predetermined set of poses. The experimental results show that, with a few training examples, the system reaches high accuracy and robustness. This method shows how to combine data from the visual and auditory systems for the acquisition of new knowledge in a natural manner. Such a natural way of training enables robots to learn from users, even if they are not experts in robotics. PMID:24048336

  7. LEVELING STUDENTS’ CREATIVE THINKING IN SOLVING AND POSING MATHEMATICAL PROBLEM

    Directory of Open Access Journals (Sweden)

    Tatag Yuli Eko Siswono

    2010-07-01

    Full Text Available Many researchers assume that people are creative, but their degree ofcreativity is different. The notion of creative thinking level has beendiscussed .by experts. The perspective of mathematics creative thinkingrefers to a combination of logical and divergent thinking which is basedon intuition but has a conscious aim. The divergent thinking is focusedon flexibility, fluency, and novelty in mathematical problem solving andproblem posing. As students have various backgrounds and differentabilities, they possess different potential in thinking patterns,imagination, fantasy and performance; therefore, students have differentlevels of creative thinking. A research study was conducted in order todevelop a framework for students’ levels of creative thinking inmathematics. This research used a qualitative approach to describe thecharacteristics of the levels of creative thinking. Task-based interviewswere conducted to collect data with ten 8thgrade junior secondary schoolstudents. The results distinguished five levels of creative thinking,namely level 0 to level 4 with different characteristics in each level.These differences are based on fluency, flexibility, and novelty inmathematical problem solving and problem posing.Keywords: student’s creative thinking, problem posing, flexibility,fluency, novelty DOI: http://dx.doi.org/10.22342/jme.1.1.794.17-40

  8. Teaching Human Poses Interactively to a Social Robot

    Directory of Open Access Journals (Sweden)

    Miguel A. Salichs

    2013-09-01

    Full Text Available The main activity of social robots is to interact with people. In order to do that, the robot must be able to understand what the user is saying or doing. Typically, this capability consists of pre-programmed behaviors or is acquired through controlled learning processes, which are executed before the social interaction begins. This paper presents a software architecture that enables a robot to learn poses in a similar way as people do. That is, hearing its teacher’s explanations and acquiring new knowledge in real time. The architecture leans on two main components: an RGB-D (Red-, Green-, Blue- Depth -based visual system, which gathers the user examples, and an Automatic Speech Recognition (ASR system, which processes the speech describing those examples. The robot is able to naturally learn the poses the teacher is showing to it by maintaining a natural interaction with the teacher. We evaluate our system with 24 users who teach the robot a predetermined set of poses. The experimental results show that, with a few training examples, the system reaches high accuracy and robustness. This method shows how to combine data from the visual and auditory systems for the acquisition of new knowledge in a natural manner. Such a natural way of training enables robots to learn from users, even if they are not experts in robotics.

  9. Postoperative Feeding Difficulties after Repair of Congenital ...

    African Journals Online (AJOL)

    Of these, 24 (37.5%) developed feeding difficulties in the immediate post operative period. The causes of the feeding difficulties were Gastro-oesophageal reflux (GOR) 9, Recurrent diaphragmatic hernia 8, Adhesive intestinal obstruction 4, Poor intestinal motility 2, Campylobacter enteritis, 1, Hypertrophic pyloric stenosis, 1.

  10. Students’ difficulties in probabilistic problem-solving

    Science.gov (United States)

    Arum, D. P.; Kusmayadi, T. A.; Pramudya, I.

    2018-03-01

    There are many errors can be identified when students solving mathematics problems, particularly in solving the probabilistic problem. This present study aims to investigate students’ difficulties in solving the probabilistic problem. It focuses on analyzing and describing students errors during solving the problem. This research used the qualitative method with case study strategy. The subjects in this research involve ten students of 9th grade that were selected by purposive sampling. Data in this research involve students’ probabilistic problem-solving result and recorded interview regarding students’ difficulties in solving the problem. Those data were analyzed descriptively using Miles and Huberman steps. The results show that students have difficulties in solving the probabilistic problem and can be divided into three categories. First difficulties relate to students’ difficulties in understanding the probabilistic problem. Second, students’ difficulties in choosing and using appropriate strategies for solving the problem. Third, students’ difficulties with the computational process in solving the problem. Based on the result seems that students still have difficulties in solving the probabilistic problem. It means that students have not able to use their knowledge and ability for responding probabilistic problem yet. Therefore, it is important for mathematics teachers to plan probabilistic learning which could optimize students probabilistic thinking ability.

  11. Researching Learning Difficulties: A Guide for Practitioners

    Science.gov (United States)

    Porter, Jill; Lacey, Penny

    2005-01-01

    The aim of this book is to provide a source for teachers and other professionals working with children and adults with learning difficulties and disabilities that will enable them to: (1) access selected recent and relevant research in the field of learning difficulties, drawn from a range of disciplines and groups of people; (2) reflect on…

  12. Process-based Assignment-Setting Change for Support of Overcoming Bottlenecks in Learning by Problem-Posing in Arithmetic Word Problems

    Science.gov (United States)

    Supianto, A. A.; Hayashi, Y.; Hirashima, T.

    2017-02-01

    Problem-posing is well known as an effective activity to learn problem-solving methods. Monsakun is an interactive problem-posing learning environment to facilitate arithmetic word problems learning for one operation of addition and subtraction. The characteristic of Monsakun is problem-posing as sentence-integration that lets learners make a problem of three sentences. Monsakun provides learners with five or six sentences including dummies, which are designed through careful considerations by an expert teacher as a meaningful distraction to the learners in order to learn the structure of arithmetic word problems. The results of the practical use of Monsakun in elementary schools show that many learners have difficulties in arranging the proper answer at the high level of assignments. The analysis of the problem-posing process of such learners found that their misconception of arithmetic word problems causes impasses in their thinking and mislead them to use dummies. This study proposes a method of changing assignments as a support for overcoming bottlenecks of thinking. In Monsakun, the bottlenecks are often detected as a frequently repeated use of a specific dummy. If such dummy can be detected, it is the key factor to support learners to overcome their difficulty. This paper discusses how to detect the bottlenecks and to realize such support in learning by problem-posing.

  13. Do dyslexics have auditory input processing difficulties?

    DEFF Research Database (Denmark)

    Poulsen, Mads

    2011-01-01

    Word production difficulties are well documented in dyslexia, whereas the results are mixed for receptive phonological processing. This asymmetry raises the possibility that the core phonological deficit of dyslexia is restricted to output processing stages. The present study investigated whether....... The finding suggests that input processing difficulties are associated with the phonological deficit, but that these difficulties may be stronger above the level of phoneme perception.......Word production difficulties are well documented in dyslexia, whereas the results are mixed for receptive phonological processing. This asymmetry raises the possibility that the core phonological deficit of dyslexia is restricted to output processing stages. The present study investigated whether...... a group of dyslexics had word level receptive difficulties using an auditory lexical decision task with long words and nonsense words. The dyslexics were slower and less accurate than chronological age controls in an auditory lexical decision task, with disproportionate low performance on nonsense words...

  14. Some types of difficulty encountered during the simulation of heat exchangers (1961)

    International Nuclear Information System (INIS)

    Bettembourg, D.

    1961-01-01

    After recalling that the simulation of exchangers poses problems which are often difficult to solve, the author points out that these problems appear first of all when the physical phenomena are described in terms of equations. They appear also during the solving of the equations since expressions which are more and more complex can give rise to unstable electronic structures. These difficulties are developed during the analysis of various types of exchangers and in each case the solutions chosen are given. (author) [fr

  15. ONKALO POSE experiment. Phase 3: execution and monitoring

    International Nuclear Information System (INIS)

    Valli, J.; Hakala, M.; Wanne, T.; Kantia, P.; Siren, T.

    2014-01-01

    In-depth knowledge of the in situ stress state at the Olkiluoto site is critical for stability assessment both prior to and after deposition of spent nuclear fuel in order to understand and avoid potential damage to the rock at the site. Posiva's Olkiluoto Spalling Experiment (POSE) was designed specifically for this purpose with three primary goals: establish the in situ spalling/damage strength of Olkiluoto migmatitic gneiss, establish the state of in situ stress at the -345 m depth level and act as a Prediction-Outcome (P-O) exercise. Phases 1 and 2 of POSE are outlined in WR 2012-60. The objectives of the third phase of the POSE experiment are the same as the original objectives outlined above. This report outlines the execution and results of the third phase of the POSE experiment. The third phase of the experiment involved internally heating the third experimental hole (ONK-EH3) of the POSE niche in order to cause a symmetrical thermal stress increase around the hole due to the thermal expansion of rock. This thermomechanically induced stress increase, coupled with the estimated existing in situ stress state, should cause the maximum principal stress around the hole to exceed the predicted spalling strength of the rock around the hole. ONK-EH3 is located almost completely in pegmatitic granite. Four fractures near the top of the hole were mapped after boring ONK-EH3, and a tensile failure located at the contact between mica-rich gneiss and pegmatitic granite was observed 18 months after boring, prior to the experiment. Based on predictive calculations and the estimated in situ state of stress, the maximum principal stress magnitude should reach ca. 100 MPa when the temperature was just below 100 deg C after 12 weeks of heating. There were problems with the heater control unit at the beginning of the experiment, after which heating proceeded according to plan. The crack damage threshold of pegmatitic granite has been determined to be 85 ±17 MPa at Olkiluoto

  16. Understanding the threats posed by non-native species: public vs. conservation managers.

    Directory of Open Access Journals (Sweden)

    Rodolphe E Gozlan

    Full Text Available Public perception is a key factor influencing current conservation policy. Therefore, it is important to determine the influence of the public, end-users and scientists on the prioritisation of conservation issues and the direct implications for policy makers. Here, we assessed public attitudes and the perception of conservation managers to five non-native species in the UK, with these supplemented by those of an ecosystem user, freshwater anglers. We found that threat perception was not influenced by the volume of scientific research or by the actual threats posed by the specific non-native species. Media interest also reflected public perception and vice versa. Anglers were most concerned with perceived threats to their recreational activities but their concerns did not correspond to the greatest demonstrated ecological threat. The perception of conservation managers was an amalgamation of public and angler opinions but was mismatched to quantified ecological risks of the species. As this suggests that invasive species management in the UK is vulnerable to a knowledge gap, researchers must consider the intrinsic characteristics of their study species to determine whether raising public perception will be effective. The case study of the topmouth gudgeon Pseudorasbora parva reveals that media pressure and political debate has greater capacity to ignite policy changes and impact studies on non-native species than scientific evidence alone.

  17. Relative Pose Estimation and Accuracy Verification of Spherical Panoramic Image

    Directory of Open Access Journals (Sweden)

    XIE Donghai

    2017-11-01

    Full Text Available This paper improves the method of the traditional 5-point relative pose estimation algorithm, and proposes a relative pose estimation algorithm which is suitable for spherical panoramic images. The algorithm firstly computes the essential matrix, then decomposes the essential matrix to obtain the rotation matrix and the translation vector using SVD, and finally the reconstructed three-dimensional points are used to eliminate the error solution. The innovation of the algorithm lies the derivation of panorama epipolar formula and the use of the spherical distance from the point to the epipolar plane as the error term for the spherical panorama co-planarity function. The simulation experiment shows that when the random noise of the image feature points is within the range of pixel, the error of the three Euler angles is about 0.1°, and the error between the relative translational displacement and the simulated value is about 1.5°. The result of the experiment using the data obtained by the vehicle panorama camera and the POS shows that:the error of the roll angle and pitch angle can be within 0.2°, the error of the heading angle can be within 0.4°, and the error between the relative translational displacement and the POS can be within 2°. The result of our relative pose estimation algorithm is used to generate the spherical panoramic epipolar images, then we extract the key points between the spherical panoramic images and calculate the errors in the column direction. The result shows that the errors is less than 1 pixel.

  18. Mastoidectomy: anatomical parameters x surgical difficulty

    Directory of Open Access Journals (Sweden)

    Pereira Júnior, Anastácio Rodrigues

    2012-01-01

    Full Text Available Introduction: The lowered temporal meninges and/ or anterior sigmoid sinus are contiditions that can determine surgical difficulties in performing mastoidectomy. Objective: To correlate in the tomography the extent of the prolapse of the sigmoid sinus and of temporal meninges with the surgical difficulty in the mastoidectomy. Method: The tomographic measurements of prolapse sigmoid and of temporal meninges were correlated with the presence or non-presence of the surgical difficulty observed during the mastoidectomy procedure in patients with ostomatoiditis chronic (n=30. Form of study: Contemporary cohort transverse. Results: In 10 patients were observed surgical difficulty distributed as: due to prolapse of the sigmoid sinus (n = 2 or temporal meninges prolapse (n = 7 or both (n = 1. In patients in which the surgical difficulty was due to sigmoid sinus prolapse, the tomography distance of the anterior border of the sigmoid sinus to posterior wall of external auditory canal was lower than 9 mm. In patients in which surgical difficulty was due to temporal meninges prolapse, the tomographic distance to the upper plane of the petrous bone was 7 mm. Conclusion: The computerized tomography distance between the temporal meninges and the upper plane of the petrous bone 7 mm and the distance of the anterior border of the sigmoid sinus to posterior wall of external auditory canal was lower than 9 mm are predictive to the surgical difficulties to perform mastoidectomy.

  19. Regularization theory for ill-posed problems selected topics

    CERN Document Server

    Lu, Shuai

    2013-01-01

    Thismonograph is a valuable contribution to thehighly topical and extremly productive field ofregularisationmethods for inverse and ill-posed problems. The author is an internationally outstanding and acceptedmathematicianin this field. In his book he offers a well-balanced mixtureof basic and innovative aspects.He demonstrates new,differentiatedviewpoints, and important examples for applications. The bookdemontrates thecurrent developments inthe field of regularization theory,such as multiparameter regularization and regularization in learning theory. The book is written for graduate and PhDs

  20. Motor and Coordination Difficulties in Children with Emotional and Behavioural Difficulties

    Science.gov (United States)

    Hill, Elisabeth; Pratt, Michelle L; Kanji, Zara; Bartoli, Alice Jones

    2017-01-01

    To date, very few studies have explored the incidence of motor impairment amongst children with social, emotional and behavioural difficulties (social, emotional and mental health (SEMH); formerly SEBD in England). Following research that suggests an increase in motor difficulties in young children and adolescents with SEMH difficulties, this…

  1. LEARNING DIFFICULTIES: AN ANALYSIS BASED ON VIGOTSKY

    Directory of Open Access Journals (Sweden)

    Adriane Cenci

    2010-06-01

    Full Text Available We aimed, along the text, to bring a reflection upon learning difficulties based on Socio-Historical Theory, relating what is observed in schools to what has been discussed about learning difficulties and the theory proposed by Vygotsky in the early XX century. We understand that children enter school carrying experiences and knowledge from their cultural group and that school ignores such knowledge very often. Then, it is in such disengagement that emerges what we started to call learning difficulties. One cannot forget to see a child as a whole – a student is a social being constituted by culture, language and specific values to which one must be attentive.

  2. Novelty Detection for Interactive Pose Recognition by a Social Robot

    Directory of Open Access Journals (Sweden)

    Victor Gonzalez-Pacheco

    2015-04-01

    Full Text Available Active robot learners take an active role in their own learning by making queries to their human teachers when they receive new data. However, not every received input is useful for the robot, and asking for non-informative inputs or asking too many questions might worsen the user's perception of the robot. We present a novelty detection system that enables a robot to ask labels for new stimuli only when they seem both novel and interesting. Our system separates the decision process into two steps: first, it discriminates novel from known stimuli, and second, it estimates if these stimuli are likely to happen again. Our approach uses the notion of curiosity, which controls the eagerness with which the robot asks questions to the user. We evaluate our approach in the domain of pose learning by training our robot with a set of pointing poses able to detect up to 84%, 79%, and 78% of the observed novelties in three different experiments. Our approach enables robots to keep learning continuously, even after training is finished. The introduction of the curiosity parameter allows tuning, for the conditions in which the robot should want to learn more.

  3. Probabilistic Mapping of Human Visual Attention from Head Pose Estimation

    Directory of Open Access Journals (Sweden)

    Andrea Veronese

    2017-10-01

    Full Text Available Effective interaction between a human and a robot requires the bidirectional perception and interpretation of actions and behavior. While actions can be identified as a directly observable activity, this might not be sufficient to deduce actions in a scene. For example, orienting our face toward a book might suggest the action toward “reading.” For a human observer, this deduction requires the direction of gaze, the object identified as a book and the intersection between gaze and book. With this in mind, we aim to estimate and map human visual attention as directed to a scene, and assess how this relates to the detection of objects and their related actions. In particular, we consider human head pose as measurement to infer the attention of a human engaged in a task and study which prior knowledge should be included in such a detection system. In a user study, we show the successful detection of attention to objects in a typical office task scenario (i.e., reading, working with a computer, studying an object. Our system requires a single external RGB camera for head pose measurements and a pre-recorded 3D point cloud of the environment.

  4. Laser Remediation of Threats Posed by Small Orbital Debris

    Science.gov (United States)

    Fork, Richard L.; Rogers, Jan R.; Hovater, Mary A.

    2012-01-01

    The continually increasing amount of orbital debris in near Earth space poses an increasing challenge to space situational awareness. Recent collisions of spacecraft caused abrupt increases in the density of both large and small debris in near Earth space. An especially challenging class of threats is that due to the increasing density of small (1 mm to 10 cm dimension) orbital debris. This small debris poses a serious threat since: (1) The high velocity enables even millimeter dimension debris to cause serious damage to vulnerable areas of space assets, e.g., detector windows; (2) The small size and large number of debris elements prevent adequate detection and cataloguing. We have identified solutions to this threat in the form of novel laser systems and novel ways of using these laser systems. While implementation of the solutions we identify is challenging we find approaches offering threat mitigation within time frames and at costs of practical interest. We base our analysis on the unique combination of coherent light specifically structured in both space and time and applied in novel ways entirely within the vacuum of space to deorbiting small debris. We compare and contrast laser based small debris removal strategies using ground based laser systems with strategies using space based laser systems. We find laser systems located and used entirely within space offer essential and decisive advantages over groundbased laser systems.

  5. Determining the Performances of Pre-Service Primary School Teachers in Problem Posing Situations

    Science.gov (United States)

    Kilic, Cigdem

    2013-01-01

    This study examined the problem posing strategies of pre-service primary school teachers in different problem posing situations (PPSs) and analysed the issues they encounter while posing problems. A problem posing task consisting of six PPSs (two free, two structured, and two semi-structured situations) was delivered to 40 participants.…

  6. Player Modeling for Intelligent Difficulty Adjustment

    Science.gov (United States)

    Missura, Olana; Gärtner, Thomas

    In this paper we aim at automatically adjusting the difficulty of computer games by clustering players into different types and supervised prediction of the type from short traces of gameplay. An important ingredient of video games is to challenge players by providing them with tasks of appropriate and increasing difficulty. How this difficulty should be chosen and increase over time strongly depends on the ability, experience, perception and learning curve of each individual player. It is a subjective parameter that is very difficult to set. Wrong choices can easily lead to players stopping to play the game as they get bored (if underburdened) or frustrated (if overburdened). An ideal game should be able to adjust its difficulty dynamically governed by the player’s performance. Modern video games utilise a game-testing process to investigate among other factors the perceived difficulty for a multitude of players. In this paper, we investigate how machine learning techniques can be used for automatic difficulty adjustment. Our experiments confirm the potential of machine learning in this application.

  7. ONKALO POSE experiment. Phase 1 and 2: execution and monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Johansson, E. [Saanio and Riekkola Oy, Helsinki (Finland); Siren, T. [Posiva Oy, Helsinki (Finland); Hakala, M. [KMS-Hakala Oy, Nokia (Finland); Kantia, P. [Geofcon Oy, Rovaniemi (Finland)

    2014-02-15

    Posiva has conducted in the ONKALO rock characterisation facility during 2010 - 2011 an in situ experiment named POSE (Posiva's Olkiluoto Spalling Experiment). The POSE experiment had three objectives: to establish the in situ spalling/damage strength of Olkiluoto migmatitic gneiss, to establish the state of in situ stress at the -345 m depth level, and to act as a Prediction-Outcome (P-O) exercise. The POSE experiment consisted of drilling with full-face boring machine two near fullscale deposition holes, diameter 1.52 m (compared to 1.75 m for the actual deposition holes), to a depth of 7.2 m, leaving a 0.9 m pillar between the holes. The holes were planned to be located in such way that maximum excavation-induced stresses could act in the pillar and damage could then take place. Boring of the two holes in 2010 was called Phase 1 (Pillar test). This was followed in 2011 by Phase 2 (Pillar heating test) where four heaters with a length of 7.5 m heated the test area to increase the stresses around the experimental holes. In the heating phase the other hole was back-filled with sand. The test was extensively monitored during the execution using temperature monitoring, strain gauge monitoring, video monitoring, microseismic monitoring and pressure monitoring. In addition, the holes were after the test measured using ground penetration radar (GPR) and 3D photogrammetry for detailed modelling. The outcomes from the test showed that no damage, except for three opened/sheared fractures, was noticed during the boring of the holes (Phase 1). Surface damage was, though, induced by heating (Phase 2). The damage was well localized around the holes and controlled by the foliation (mica rich layers) and rock type contacts which were known to be relatively weak. Surface type failures were not observed in the gneiss, but it was noticed in limited areas in the pegmatite-granite. The depths of the damaged areas due to heating were less than 100 mm. The depths and sizes of the

  8. Macrobend optical sensing for pose measurement in soft robot arms

    International Nuclear Information System (INIS)

    Sareh, Sina; Noh, Yohan; Liu, Hongbin; Althoefer, Kaspar; Li, Min; Ranzani, Tommaso

    2015-01-01

    This paper introduces a pose-sensing system for soft robot arms integrating a set of macrobend stretch sensors. The macrobend sensory design in this study consists of optical fibres and is based on the notion that bending an optical fibre modulates the intensity of the light transmitted through the fibre. This sensing method is capable of measuring bending, elongation and compression in soft continuum robots and is also applicable to wearable sensing technologies, e.g. pose sensing in the wrist joint of a human hand. In our arrangement, applied to a cylindrical soft robot arm, the optical fibres for macrobend sensing originate from the base, extend to the tip of the arm, and then loop back to the base. The connectors that link the fibres to the necessary opto-electronics are all placed at the base of the arm, resulting in a simplified overall design. The ability of this custom macrobend stretch sensor to flexibly adapt its configuration allows preserving the inherent softness and compliance of the robot which it is installed on. The macrobend sensing system is immune to electrical noise and magnetic fields, is safe (because no electricity is needed at the sensing site), and is suitable for modular implementation in multi-link soft continuum robotic arms. The measurable light outputs of the proposed stretch sensor vary due to bend-induced light attenuation (macrobend loss), which is a function of the fibre bend radius as well as the number of repeated turns. The experimental study conducted as part of this research revealed that the chosen bend radius has a far greater impact on the measured light intensity values than the number of turns (if greater than five). Taking into account that the bend radius is the only significantly influencing design parameter, the macrobend stretch sensors were developed to create a practical solution to the pose sensing in soft continuum robot arms. Henceforward, the proposed sensing design was benchmarked against an electromagnetic

  9. ONKALO POSE experiment. Phase 1 and 2: execution and monitoring

    International Nuclear Information System (INIS)

    Johansson, E.; Siren, T.; Hakala, M.; Kantia, P.

    2014-02-01

    Posiva has conducted in the ONKALO rock characterisation facility during 2010 - 2011 an in situ experiment named POSE (Posiva's Olkiluoto Spalling Experiment). The POSE experiment had three objectives: to establish the in situ spalling/damage strength of Olkiluoto migmatitic gneiss, to establish the state of in situ stress at the -345 m depth level, and to act as a Prediction-Outcome (P-O) exercise. The POSE experiment consisted of drilling with full-face boring machine two near fullscale deposition holes, diameter 1.52 m (compared to 1.75 m for the actual deposition holes), to a depth of 7.2 m, leaving a 0.9 m pillar between the holes. The holes were planned to be located in such way that maximum excavation-induced stresses could act in the pillar and damage could then take place. Boring of the two holes in 2010 was called Phase 1 (Pillar test). This was followed in 2011 by Phase 2 (Pillar heating test) where four heaters with a length of 7.5 m heated the test area to increase the stresses around the experimental holes. In the heating phase the other hole was back-filled with sand. The test was extensively monitored during the execution using temperature monitoring, strain gauge monitoring, video monitoring, microseismic monitoring and pressure monitoring. In addition, the holes were after the test measured using ground penetration radar (GPR) and 3D photogrammetry for detailed modelling. The outcomes from the test showed that no damage, except for three opened/sheared fractures, was noticed during the boring of the holes (Phase 1). Surface damage was, though, induced by heating (Phase 2). The damage was well localized around the holes and controlled by the foliation (mica rich layers) and rock type contacts which were known to be relatively weak. Surface type failures were not observed in the gneiss, but it was noticed in limited areas in the pegmatite-granite. The depths of the damaged areas due to heating were less than 100 mm. The depths and sizes of the

  10. EFEKTIVITAS PEMBELAJARAN MATEMATIKA DENGAN METODE PROBLEM POSING BERBASIS PENDIDIKAN KARAKTER

    Directory of Open Access Journals (Sweden)

    Eka Lia Susanti

    2012-06-01

    Full Text Available Abstract Tujuan penelitian ini adalah untuk mengetahui apakah pembelajaran matematika dengan metode Problem Posing berbasis pendidikan karakter di laboratorium TeenZania pada materi garis singgung lingkaran efektif. Populasi dalam penelitian ini adalah peserta didik di SMP N 2 Pati. Sampel dalam penelitian ini diambil dengan teknik cluster random sampling. Variabel dalam penelitian ini yaitu keaktifan sebagai variabel independen dan prestasi belajar sebagai variabel dependen. Cara pengambilan data dengan lembar pengamatan dan tes. Data diolah dengan uji banding t dan uji pengaruh regresi. Hasil penelitian menunjukkan bahwa prestasi belajar kelas eksperimen (82,74 secara statistik melebihi KKM (75. Dengan uji regresi linear sederhana diperoleh persamaan regresi ?=-15,847 + 1,194X dan R^2=0,829. Koefisien X merupakan bilangan positif sehingga keaktifan berpengaruh positif pada prestasi belajar sebesar 82,9%. Rata-rata prestasi belajar kelas eksperimen (82,74 dan rata-rata prestasi belajar kelas kontrol (72,91. Secara uji stastistik prestasi belajar kelas eksperimen lebih baik daripada prestasi belajar kelas kontrol. Berdasarkan hasil analisis disimpulkan (1 pembelajaran mencapai tuntas belajar; (2 adanya pengaruh positif pada keaktifan terhadap prestasi belajar; dan (3 prestasi belajar kelas eksperimen lebih baik daripada prestasi belajar kelas kontrol; sehingga pembelajaran matematika dengan metode problem posing berbasis pendidikan karakter di laboratorium TeenZania merupakan pembelajaran yang efektif. The purpose of this study was to determine whether the learning of mathematics by Problem Posing method in a TeenZania laboratory based character education in circle tangent material effectively. The population in this study were students in SMP N 2 Pati. The sample in this study were drawn by cluster random sampling technique. The variables in this study is the activity as an independent variable and learning achievement as the dependent variable

  11. Lavrentiev regularization method for nonlinear ill-posed problems

    International Nuclear Information System (INIS)

    Kinh, Nguyen Van

    2002-10-01

    In this paper we shall be concerned with Lavientiev regularization method to reconstruct solutions x 0 of non ill-posed problems F(x)=y o , where instead of y 0 noisy data y δ is an element of X with absolut(y δ -y 0 ) ≤ δ are given and F:X→X is an accretive nonlinear operator from a real reflexive Banach space X into itself. In this regularization method solutions x α δ are obtained by solving the singularly perturbed nonlinear operator equation F(x)+α(x-x*)=y δ with some initial guess x*. Assuming certain conditions concerning the operator F and the smoothness of the element x*-x 0 we derive stability estimates which show that the accuracy of the regularized solutions is order optimal provided that the regularization parameter α has been chosen properly. (author)

  12. Pose Tracking Algorithm of an Endoscopic Surgery Robot Wrist

    International Nuclear Information System (INIS)

    Wang, L; Yin, H L; Meng, Q

    2006-01-01

    In recent two decades, more and more research on the endoscopic surgery has been carried out [2]. Most of the work focuses on the development of the robot in the field of robotics and the navigation of the surgery tools based on computer graphics. But the tracking and locating of the EndoWrist is also a very important aspect. This paper deals with the the tracking algorithm of the EndoWrist's pose (position and orientation). The linear tracking of the position is handled by the Kalman Filter. The quaternion-based nonlinear orientation tracking is implemented with the Extended Kalman Filter. The most innovative point of this paper is the parameterization of the motion model of the Extended Kalman Filter

  13. Pose Tracking Algorithm of an Endoscopic Surgery Robot Wrist

    Energy Technology Data Exchange (ETDEWEB)

    Wang, L [Chinese-German Institute of Automatic Control Engineering, Tongji University (China); Yin, H L [Chinese-German Institute of Automatic Control Engineering, Tongji University (China); Meng, Q [Shanghai University of Electric Power (China)

    2006-10-15

    In recent two decades, more and more research on the endoscopic surgery has been carried out [2]. Most of the work focuses on the development of the robot in the field of robotics and the navigation of the surgery tools based on computer graphics. But the tracking and locating of the EndoWrist is also a very important aspect. This paper deals with the the tracking algorithm of the EndoWrist's pose (position and orientation). The linear tracking of the position is handled by the Kalman Filter. The quaternion-based nonlinear orientation tracking is implemented with the Extended Kalman Filter. The most innovative point of this paper is the parameterization of the motion model of the Extended Kalman Filter.

  14. Challenges Posed by Novel Psychoactive Substances – Middle East Perspective

    Directory of Open Access Journals (Sweden)

    Maciej J. Bogusz

    2017-04-01

    Full Text Available New psychoactive substances (NPS are defined as substances of abuse, either in a pure form or a preparation, that are not controlled by the 1961 Single Convention on Narcotic Drugs or the 1971 Convention on Psychotropic Substances, but which may pose a public health threat. In this context, the term “new” does not necessarily refer to new inventions but to substances that have recently become available or popular in a given society or country. This definition indicates that the problem of NPS is not new; however, the availability of any information via new communication technologies in the 21st century has enabled the spread of unwanted and socially harmful information, like information on the commercial availability of various NPS, offered in rising amounts and brands.

  15. The effect of problem posing and problem solving with realistic mathematics education approach to the conceptual understanding and adaptive reasoning

    Science.gov (United States)

    Mahendra, Rengga; Slamet, Isnandar; Budiyono

    2017-12-01

    One of the difficulties of students in learning mathematics is on the subject of geometry that requires students to understand abstract things. The aim of this research is to determine the effect of learning model Problem Posing and Problem Solving with Realistic Mathematics Education Approach to conceptual understanding and students' adaptive reasoning in learning mathematics. This research uses a kind of quasi experimental research. The population of this research is all seventh grade students of Junior High School 1 Jaten, Indonesia. The sample was taken using stratified cluster random sampling technique. The test of the research hypothesis was analyzed by using t-test. The results of this study indicate that the model of Problem Posing learning with Realistic Mathematics Education Approach can improve students' conceptual understanding significantly in mathematics learning. In addition tu, the results also showed that the model of Problem Solving learning with Realistic Mathematics Education Approach can improve students' adaptive reasoning significantly in learning mathematics. Therefore, the model of Problem Posing and Problem Solving learning with Realistic Mathematics Education Approach is appropriately applied in mathematics learning especially on the subject of geometry so as to improve conceptual understanding and students' adaptive reasoning. Furthermore, the impact can improve student achievement.

  16. Level of environmental threat posed by horticultural trade in Cactaceae.

    Science.gov (United States)

    Novoa, Ana; Le Roux, Johannes J; Richardson, David M; Wilson, John R U

    2017-10-01

    Ornamental horticulture has been identified as an important threat to plant biodiversity and is a major pathway for plant invasions worldwide. In this context, the family Cactaceae is particularly challenging because it is considered the fifth most threatened large taxonomic group in the world; several species are among the most widespread and damaging invasive species; and Cactaceae is one of the most popular horticultural plant groups. Based on the Convention on International Trade in Endangered Species of Wild Flora and Fauna and the 11 largest online auction sites selling cacti, we documented the international cactus trade. To provide an in-depth look at the dynamics of the industry, we surveyed the businesses involved in the cactus trade in South Africa (a hotspot of cactus trade and invasions). We purchased seeds of every available species and used DNA barcoding to identify species to the genus level. Although <20% of this trade involved threatened species and <3% involved known invasive species, many species were identified by a common name. However, only 0.02% of the globally traded cacti were collected from wild populations. Despite a large commercial network, all South African imports (of which 15% and 1.5% were of species listed as threatened and invasive, respectively) came from the same source. With DNA barcoding, we identified 24% of the species to genus level. Based on our results, we believe that if trade restrictions are placed on the small proportion of cacti that are invasive and there is no major increase in harvesting of native populations, then the commercial trade in cactus poses a negligible environmental threat. However, there are currently no effective methods for easily identifying which cacti are traded, and both the illicit harvesting of cacti from the wild and the informal trade in invasive taxa pose on-going conservation challenges. © 2017 Society for Conservation Biology.

  17. Students’ difficulties in solving linear equation problems

    Science.gov (United States)

    Wati, S.; Fitriana, L.; Mardiyana

    2018-03-01

    A linear equation is an algebra material that exists in junior high school to university. It is a very important material for students in order to learn more advanced mathematics topics. Therefore, linear equation material is essential to be mastered. However, the result of 2016 national examination in Indonesia showed that students’ achievement in solving linear equation problem was low. This fact became a background to investigate students’ difficulties in solving linear equation problems. This study used qualitative descriptive method. An individual written test on linear equation tasks was administered, followed by interviews. Twenty-one sample students of grade VIII of SMPIT Insan Kamil Karanganyar did the written test, and 6 of them were interviewed afterward. The result showed that students with high mathematics achievement donot have difficulties, students with medium mathematics achievement have factual difficulties, and students with low mathematics achievement have factual, conceptual, operational, and principle difficulties. Based on the result there is a need of meaningfulness teaching strategy to help students to overcome difficulties in solving linear equation problems.

  18. Numerical Magnitude Representation in Children With Mathematical Difficulties With or Without Reading Difficulties.

    Science.gov (United States)

    Tobia, Valentina; Fasola, Anna; Lupieri, Alice; Marzocchi, Gian Marco

    2016-01-01

    This study aimed to explore the spatial numerical association of response codes (SNARC), the flanker, and the numerical distance effects in children with mathematical difficulties. From a sample of 720 third, fourth, and fifth graders, 60 children were selected and divided into the following three groups: typically developing children (TD; n = 29), children with mathematical difficulties only (MD only; n = 21), and children with mathematical and reading difficulties (MD+RD; n = 10). Children were tested with a numerical Eriksen task that was built to assess SNARC, numerical distance, and flanker (first and second order congruency) effects. Children with MD only showed stronger SNARC and second order congruency effects than did TD children, whereas the numerical distance effects were similar across the three groups. Finally, the first order congruency effect was associated with reading difficulties. These results showed that children with mathematical difficulties with or without reading difficulties were globally more impaired when spatial incompatibilities were presented. © Hammill Institute on Disabilities 2014.

  19. Working Memory in Students with Mathematical Difficulties

    Science.gov (United States)

    Nur, I. R. D.; Herman, T.; Ningsih, S.

    2018-04-01

    Learning process is the activities that has important role because this process is one of the all factors that establish students success in learning. oftentimes we find so many students get the difficulties when they study mathematics. This condition is not only because of the outside factor but also it comes from the inside. The purpose of this research is to analyze and give the representation how students working memory happened in physical education students for basic statistics subjects which have mathematical difficulties. The subjects are 4 students which have a mathematical difficulties. The research method is case study and when the describe about students working memory are explanated deeply with naturalistic observation. Based on this research, it was founded that 4 students have a working memory deficit in three components. The components are phonological loop, visuospatial sketchpad, dan episodic buffer.

  20. Tinnitus and Sleep Difficulties After Cochlear Implantation.

    Science.gov (United States)

    Pierzycki, Robert H; Edmondson-Jones, Mark; Dawes, Piers; Munro, Kevin J; Moore, David R; Kitterick, Pádraig T

    To estimate and compare the prevalence of and associations between tinnitus and sleep difficulties in a sample of UK adult cochlear implant users and those identified as potential candidates for cochlear implantation. The study was conducted using the UK Biobank resource, a population-based cohort of 40- to 69-year olds. Self-report data on hearing, tinnitus, sleep difficulties, and demographic variables were collected from cochlear implant users (n = 194) and individuals identified as potential candidates for cochlear implantation (n = 211). These "candidates" were selected based on (i) impaired hearing sensitivity, inferred from self-reported hearing aid use and (ii) impaired hearing function, inferred from an inability to report words accurately at negative signal to noise ratios on an unaided closed-set test of speech perception. Data on tinnitus (presence, persistence, and related distress) and on sleep difficulties were analyzed using logistic regression models controlling for gender, age, deprivation, and neuroticism. The prevalence of tinnitus was similar among implant users (50%) and candidates (52%; p = 0.39). However, implant users were less likely to report that their tinnitus was distressing at its worst (41%) compared with candidates (63%; p = 0.02). The logistic regression model suggested that this difference between the two groups could be explained by the fact that tinnitus was less persistent in implant users (46%) compared with candidates (72%; p reported difficulties with sleep were similar among implant users (75%) and candidates (82%; p = 0.28), but participants with tinnitus were more likely to report sleep difficulties than those without (p explanation is supported by the similar prevalence of sleep problems among implant users and potential candidates for cochlear implantation, despite differences between the groups in tinnitus persistence and related emotional distress. Cochlear implantation may therefore not be an appropriate intervention

  1. Assessing the risk posed by natural hazards to infrastructures

    Science.gov (United States)

    Eidsvig, Unni Marie K.; Kristensen, Krister; Vidar Vangelsten, Bjørn

    2017-03-01

    This paper proposes a model for assessing the risk posed by natural hazards to infrastructures, with a focus on the indirect losses and loss of stability for the population relying on the infrastructure. The model prescribes a three-level analysis with increasing level of detail, moving from qualitative to quantitative analysis. The focus is on a methodology for semi-quantitative analyses to be performed at the second level. The purpose of this type of analysis is to perform a screening of the scenarios of natural hazards threatening the infrastructures, identifying the most critical scenarios and investigating the need for further analyses (third level). The proposed semi-quantitative methodology considers the frequency of the natural hazard, different aspects of vulnerability, including the physical vulnerability of the infrastructure itself, and the societal dependency on the infrastructure. An indicator-based approach is applied, ranking the indicators on a relative scale according to pre-defined ranking criteria. The proposed indicators, which characterise conditions that influence the probability of an infrastructure malfunctioning caused by a natural event, are defined as (1) robustness and buffer capacity, (2) level of protection, (3) quality/level of maintenance and renewal, (4) adaptability and quality of operational procedures and (5) transparency/complexity/degree of coupling. Further indicators describe conditions influencing the socio-economic consequences of the infrastructure malfunctioning, such as (1) redundancy and/or substitution, (2) cascading effects and dependencies, (3) preparedness and (4) early warning, emergency response and measures. The aggregated risk estimate is a combination of the semi-quantitative vulnerability indicators, as well as quantitative estimates of the frequency of the natural hazard, the potential duration of the infrastructure malfunctioning (e.g. depending on the required restoration effort) and the number of users of

  2. Invasive Lionfish (Pterosis volitans) Pose Public Health Threats.

    Science.gov (United States)

    Diaz, James H

    2015-01-01

    The lionfish, Pterosis volitans, a native of Indo-Pacific oceans, is a popular saltwater aquarium fish despite venomous spines on its fins. Lionfish were inadvertently introduced into the western Atlantic from Florida in the early 1990s and have overpopulated and dispersed widely into the Caribbean Sea and Gulf of Mexico. Initiatives to control lionfish populations were launched, including the National Oceanographic and Atmospheric Administration (NOAA)-sponsored "Lionfish as Food Campaign".2 Recently, scientists from the Food and Drug Administration (FDA) reported that lionfish caught off the US Virgin Islands contained ciguatoxins and could cause ciguatera fish poisoning (CFP); a seafood-borne poisoning without an antidote or any specific treatment, and a potential for prolonged neurotoxicity. Lionfish pose several public health threats. New strategies to control the lionfish population explosion in coastal waters and offshore fisheries are needed now to ensure seafood safety and public health. The lionfish, Pterosis volitans, is native to the reefs of the western Indian and Pacific Oceans (Figure 1). Brightly colored with red, white, and black stripes and adorned with feathery fins, the lionfish is a popular saltwater aquarium fish despite venomous spines on its fins (Figure 2). Lionfish were introduced into the western North Atlantic from Florida in the early 1990s after some specimens were discarded by dissatisfied amateur aquarists and others escaped from hurricane-flooded public aquariums.1 Since lionfish are voracious carnivores, have few natural predators, and reproduce prolifically, they have overpopulated and dispersed widely from Cape Hatteras to Florida, throughout the Caribbean Sea, and into the Gulf of Mexico.1 The population density of lionfish in its new, invaded territory now exceeds that of its native habitat.1 As a result, campaigns to control lionfish populations were launched in Florida and the Caribbean. Lionfish now pose several public

  3. NEW CONTRIBUTIONS TO READING DIFFICULTIES INTERVENTION

    Directory of Open Access Journals (Sweden)

    VÍCTOR SANTIUSTE BERMEJO

    2005-01-01

    Full Text Available This article presents a synthesis of the intervention programs and strategies to treat reading difficulties. The synthesisincludes a review of the last published articles on the issue, both in Spanish and English. It also presents the visits todifferent Language Rehabilitation Centers in the Community of Madrid including the approaches applied in thesecenters. Besides the description of the general intervention strategies applied to reading problems, some of theprograms to treat specific difficulties of words decoding and recognizing are explained, and the programs to treatreading comprehension and fluidity.

  4. [Specific problems posed by carbohydrate utilization in the rainbow trout].

    Science.gov (United States)

    Bergot, F

    1979-01-01

    Carbohydrate incorporation in trout diets arises problems both at digestive and metabolic levels. Digestive utilization of carbohydrate closely depends on their molecular weight. In addition, in the case of complex carbohydrates (starches), different factors such as the level of incorporation, the amount consumed and the physical state of starch influence the digestibility. The measurement of digestibility in itself is confronted with methodological difficulties. The way the feces are collected can affect the digestion coefficient. Dietary carbohydrates actually serve as a source of energy. Nevertheless, above a certain level in the diet, intolerance phenomena may appear. The question that arises now is to establish the optimal part that carbohydrates can take in the metabolizable energy of a given diet.

  5. Practical difficulties in raising finance for windfarms

    International Nuclear Information System (INIS)

    Johns, J.H.

    1995-01-01

    This paper highlights factors that have influenced the financial structure of windfarms, and considers the attitude of financiers, the returns to equity investors, innovations is the tax regime, and the challenges posed by the NFF03. The appendices lists the factors affecting the financial structures under previous versions of NFFOs, and key elements of successful schemes, and includes a diagram of the model windfarm. (Author)

  6. The STS-93 crew pose in front of Columbia

    Science.gov (United States)

    1999-01-01

    The STS-93 crew pose in front of the Space Shuttle orbiter Columbia following their landing on runway 33 at the Shuttle Landing Facility. Main gear touchdown occurred at 11:20:35 p.m. EDT on July 27. From left to right, they are Mission Specialists Catherine G. Coleman (Ph.D.) and Stephen A. Hawley (Ph.D.), Pilot Jeffrey S. Ashby, Commander Eileen Collins, and Mission Specialist Michel Tognini of France, with the Centre National d'Etudes Spatiales (CNES). The mission's primary objective was to deploy the Chandra X-ray Observatory, which will allow scientists from around the world to study some of the most distant, powerful and dynamic objects in the universe. This was the 95th flight in the Space Shuttle program and the 26th for Columbia. The landing was the 19th consecutive Shuttle landing in Florida and the 12th night landing in Shuttle program history. On this mission, Collins became the first woman to serve as a Shuttle commander.

  7. STS-93 Commander Collins poses in front of Columbia

    Science.gov (United States)

    1999-01-01

    STS-93 Commander Eileen Collins poses in front of the Space Shuttle orbiter Columbia following her textbook landing on runway 33 at the Shuttle Landing Facility. Main gear touchdown occurred at 11:20:35 p.m. EDT on July 27. On this mission, Collins became the first woman to serve as a Shuttle commander. Also on board were her fellow STS-93 crew members: Pilot Jeffrey S. Ashby and Mission Specialists Stephen A. Hawley (Ph.D.), Catherine G. Coleman (Ph.D.) and Michel Tognini of France, with the Centre National d'Etudes Spatiales (CNES). The mission's primary objective was to deploy the Chandra X-ray Observatory, which will allow scientists from around the world to study some of the most distant, powerful and dynamic objects in the universe. This was the 95th flight in the Space Shuttle program and the 26th for Columbia. The landing was the 19th consecutive Shuttle landing in Florida and the 12th night landing in Shuttle program history.

  8. Real-time pose invariant logo and pattern detection

    Science.gov (United States)

    Sidla, Oliver; Kottmann, Michal; Benesova, Wanda

    2011-01-01

    The detection of pose invariant planar patterns has many practical applications in computer vision and surveillance systems. The recognition of company logos is used in market studies to examine the visibility and frequency of logos in advertisement. Danger signs on vehicles could be detected to trigger warning systems in tunnels, or brand detection on transport vehicles can be used to count company-specific traffic. We present the results of a study on planar pattern detection which is based on keypoint detection and matching of distortion invariant 2d feature descriptors. Specifically we look at the keypoint detectors of type: i) Lowe's DoG approximation from the SURF algorithm, ii) the Harris Corner Detector, iii) the FAST Corner Detector and iv) Lepetit's keypoint detector. Our study then compares the feature descriptors SURF and compact signatures based on Random Ferns: we use 3 sets of sample images to detect and match 3 logos of different structure to find out which combinations of keypoint detector/feature descriptors work well. A real-world test tries to detect vehicles with a distinctive logo in an outdoor environment under realistic lighting and weather conditions: a camera was mounted on a suitable location for observing the entrance to a parking area so that incoming vehicles could be monitored. In this 2 hour long recording we can successfully detect a specific company logo without false positives.

  9. The role of the posed smile in overall facial esthetics.

    Science.gov (United States)

    Havens, David C; McNamara, James A; Sigler, Lauren M; Baccetti, Tiziano

    2010-03-01

    To evaluate the role of the posed smile in overall facial esthetics, as determined by laypersons and orthodontists. Twenty orthodontists and 20 lay evaluators were asked to perform six Q-sorts on different photographs of 48 white female subjects. The six Q-sorts consisted of three different photographs for each of two time points (pre- and posttreatment), as follows: (1) smile-only, (2) face without the smile, and (3) face with the smile. The evaluators determined a split-line for attractive and unattractive images at the end of each Q-sort. The proportions of attractive patients were compared across Q-sorts using a Wilcoxon signed-rank test for paired data. The evaluators also ranked nine facial/dental characteristics at the completion of the six Q-sorts. Evaluators found the pretreatment face without the smile to be significantly more attractive than the face with the smile or the smile-only photographs. Dissimilar results were seen posttreatment; there was not a significant difference between the three posttreatment photographs. The two panels agreed on the proportion of "attractive" subjects but differed on the attractiveness level of each individual subject. The presence of a malocclusion has a negative impact on facial attractiveness. Orthodontic correction of a malocclusion affects overall facial esthetics positively. Laypeople and orthodontists agree on what is attractive. Overall facial harmony is the most important characteristic used in deciding facial attractiveness.

  10. Compensating Pose Uncertainties through Appropriate Gripper Finger Cutouts

    Directory of Open Access Journals (Sweden)

    Wolniakowski Adam

    2018-03-01

    Full Text Available The gripper finger design is a recurring problem in many robotic grasping platforms used in industry. The task of switching the gripper configuration to accommodate for a new batch of objects typically requires engineering expertise, and is a lengthy and costly iterative trial-and-error process. One of the open challenges is the need for the gripper to compensate for uncertainties inherent to the workcell, e.g. due to errors in calibration, inaccurate pose estimation from the vision system, or object deformation. In this paper, we present an analysis of gripper uncertainty compensating capabilities in a sample industrial object grasping scenario for a finger that was designed using an automated simulation-based geometry optimization method (Wolniakowski et al., 2013, 2015. We test the developed gripper with a set of grasps subjected to structured perturbation in a simulation environment and in the real-world setting. We provide a comparison of the data obtained by using both of these approaches. We argue that the strong correspondence observed in results validates the use of dynamic simulation for the gripper finger design and optimization.

  11. Asynchronous vehicle pose correction using visual detection of ground features

    International Nuclear Information System (INIS)

    Harnarinesingh, Randy E S; Syan, Chanan S

    2014-01-01

    The inherent noise associated with odometry manifests itself as errors in localization for autonomous vehicles. Visual odometry has been previously used in order to supplement classical vehicle odometry. However, visual odometry is limited in its ability to reduce errors in localization for large travel distances that entail the cumulative summing of individual frame-to-frame image errors. In this paper, a novel machine vision approach for tiled surfaces is proposed to address this problem. Tile edges in a laboratory environment are used to define a travel trajectory for the Quansar Qbot (autonomous vehicle) built on the iRobot iRoomba platform with a forward facing camera. Tile intersections are used to enable asynchronous error recovery for vehicle position and orientation. The proposed approach employs real-time image classification and is feasible for error mitigation for large travel distances. The average position error for an 8m travel distance using classical odometry was measured to be 0.28m. However, implementation of the proposed approach resulted in an error of 0.028m. The proposed approach therefore significantly reduces pose estimation error and could be used to supplement existing modalities such as GPS and Laser-based range sensors

  12. Mendalami Dasar-Dasar dalam Pengambilan Pose pada Pemotretan Model

    Directory of Open Access Journals (Sweden)

    Agnes Paulina Gunawan

    2013-04-01

    Full Text Available There are many activities and numerous objects in this universe, which make them interesting for photographers to explore as their masterpiece. One of the things that has been enjoyed and is always developing over time is the use of human as an object, whether as a candid photography or as a posing model in accordance to photographer's concept and theme. Using human being as an object is always popular among beginners and professional photographers. Even nowadays people often hold photo shoot as a media in many social network sites. And so if they understand the simple theories in basic knowledge of using human object, the results will be maximized, and of course, much more interesting. The more a photographer does his job, the better his experience is, and his work will develop. Thus, it makes him more alert to the situation and character of a model, which will then become more observant in predicting their outcome in photography.   

  13. The development of a concise questionnaire designed to measure perceived outcomes on the issues of greatest importance to patients.

    Science.gov (United States)

    Busby, M; Burke, F J T; Matthews, R; Cyrta, J; Mullins, A

    2012-04-01

    To develop a concise patient feedback audit instrument designed to inform practice development on those issues of greatest importance to patients. A literature review was used to establish the issues which were of greatest importance to patients. Ten core questions were then designed with the help of an experienced survey and polling organisation. A challenging grading of patient responses was utilised in an attempt to differentiate perceived performance within a practice on the different aspects and between practices. A feasibility study was conducted using the interactive voice response mode with seven volunteer practices in 2009. The instrument was then used in the later part of 2010 by 61 practices mostly in paper-based format. Practices received feedback which is primarily based on a bar chart plotting their percentage of top grades received against a national reference sample (NRS) compiled from the results of other participating practices. A statistical analysis was conducted to establish the level at which an individual practice result becomes statistically significant against the NRS. The 61 participating practices each received an average of 121 responses (total 7,381 responses). Seventy-four percent of responses across all ten questions received the top grade, 'ideal'. Statistical analysis indicated that at the level of 121 responses, a score of around 4-9% difference to the National Reference Sample, depending on the specific question, was statistically significant. In keeping with international experience with dental patient feedback surveys this audit suggests high levels of patient satisfaction with their dental service. Nevertheless, by focusing results on the proportion of highest grades received, this instrument is capable of indicating when perceived performance falls significantly below the average. It can therefore inform practice development.

  14. Difficulties in Initial Algebra Learning in Indonesia

    Science.gov (United States)

    Jupri, Al; Drijvers, Paul; van den Heuvel-Panhuizen, Marja

    2014-01-01

    Within mathematics curricula, algebra has been widely recognized as one of the most difficult topics, which leads to learning difficulties worldwide. In Indonesia, algebra performance is an important issue. In the Trends in International Mathematics and Science Study (TIMSS) 2007, Indonesian students' achievement in the algebra domain was…

  15. Communication difficulties between radiobiologists and radiotherapists

    International Nuclear Information System (INIS)

    Revesz, L.

    1977-01-01

    The communication difficulties between radiobiologists and radiotherapists are attributable to the existence of two cultures in radiology, separated by different philosophies, values, standards and attitudes. Integrated education in the separate branches of science and joint experimental ventures are proposed in order to develop unifying concepts. (author)

  16. Fractions Learning in Children with Mathematics Difficulties

    Science.gov (United States)

    Tian, Jing; Siegler, Robert S.

    2017-01-01

    Learning fractions is difficult for children in general and especially difficult for children with mathematics difficulties (MD). Recent research on developmental and individual differences in fraction knowledge of children with MD and typically achieving (TA) children has demonstrated that U.S. children with MD start middle school behind their TA…

  17. Difficulties in initial algebra learning in Indonesia

    NARCIS (Netherlands)

    Jupri, Al; Drijvers, Paulus; van den Heuvel - Panhuizen, Marja

    2014-01-01

    Within mathematics curricula, algebra has been widely recognized as one of the most difficult topics, which leads to learning difficulties worldwide. In Indonesia, algebra performance is an important issue. In the Trends in International Mathematics and Science Study (TIMSS) 2007, Indonesian

  18. Infrared difficulties with thermal quantum field theories

    International Nuclear Information System (INIS)

    Grandou, T.

    1997-01-01

    Reviewing briefly the two main difficulties encountered in thermal quantum field theories at finite temperature when dealing with the Braaten-Pisarski (BP) resummation program, the motivation is introduced of an analysis relying on the bare perturbation theory, right from the onset. (author)

  19. Binomial test models and item difficulty

    NARCIS (Netherlands)

    van der Linden, Willem J.

    1979-01-01

    In choosing a binomial test model, it is important to know exactly what conditions are imposed on item difficulty. In this paper these conditions are examined for both a deterministic and a stochastic conception of item responses. It appears that they are more restrictive than is generally

  20. Time Estimation Deficits in Childhood Mathematics Difficulties

    Science.gov (United States)

    Hurks, Petra P. M.; van Loosbroek, Erik

    2014-01-01

    Time perception has not been comprehensively examined in mathematics difficulties (MD). Therefore, verbal time estimation, production, and reproduction were tested in 13 individuals with MD and 16 healthy controls, matched for age, sex, and intellectual skills. Individuals with MD performed comparably to controls in time reproduction, but showed a…

  1. Students' Difficulties with Vector Calculus in Electrodynamics

    Science.gov (United States)

    Bollen, Laurens; van Kampen, Paul; De Cock, Mieke

    2015-01-01

    Understanding Maxwell's equations in differential form is of great importance when studying the electrodynamic phenomena discussed in advanced electromagnetism courses. It is therefore necessary that students master the use of vector calculus in physical situations. In this light we investigated the difficulties second year students at KU Leuven…

  2. Difficulties in Learning Inheritance and Polymorphism

    Science.gov (United States)

    Liberman, Neomi; Beeri, Catriel; Kolikant, Yifat Ben-David

    2011-01-01

    This article reports on difficulties related to the concepts of inheritance and polymorphism, expressed by a group of 22 in-service CS teachers with an experience with the procedural paradigm, as they coped with a course on OOP. Our findings are based on the analysis of tests, questionnaires that the teachers completed in the course, as well as on…

  3. Learning Difficulties and Nutrition: Pills or Pedagogy?

    Science.gov (United States)

    Evans, Roy

    1999-01-01

    Examines the efforts to find effective ameliorative measures for literacy difficulties such as dyslexia and dyspraxia, focusing on noneducational techniques found in holistic medicine, complementary therapies, and nutritional supplements. Maintains that dyslexia has become big business for drug companies and that the appropriate research regarding…

  4. Mathematics Difficulties: Does One Approach Fit All?

    Science.gov (United States)

    Gifford, Sue; Rockliffe, Freda

    2012-01-01

    This article reviews the nature of learning difficulties in mathematics and, in particular, the nature and prevalence of dyscalculia, a condition that affects the acquisition of arithmetical skills. The evidence reviewed suggests that younger children (under the age of 10) often display a combination of problems, including minor physical…

  5. Quantization and hall effect: necessities and difficulties

    International Nuclear Information System (INIS)

    Ahmed Bouketir; Hishamuddin Zainuddin

    1999-01-01

    The quantization procedure is a necessary tool for a proper understanding of many interesting quantum phenomena in modern physics. In this note, we focus on geometrical framework for such procedures, particularly the group-theoretic approach and their difficulties. Finally we look through the example of Hall effect as a quantized macroscopic phenomenon with group-theoretic quantization approach. (author)

  6. Pupils' Difficulties: What Can the Teacher Do?

    Science.gov (United States)

    Dawson, C. J.

    1978-01-01

    Discusses how the teacher can deal with difficulties pupils of varying ages have in understanding certain chemical ideas. The article does not support using a Piagetian model for science courses in secondary schools. It suggests that Ausubel's learning theory is of much more use to the practicing teacher. (HM)

  7. Older Adults Have Difficulty in Decoding Sarcasm

    Science.gov (United States)

    Phillips, Louise H.; Allen, Roy; Bull, Rebecca; Hering, Alexandra; Kliegel, Matthias; Channon, Shelley

    2015-01-01

    Younger and older adults differ in performance on a range of social-cognitive skills, with older adults having difficulties in decoding nonverbal cues to emotion and intentions. Such skills are likely to be important when deciding whether someone is being sarcastic. In the current study we investigated in a life span sample whether there are…

  8. Early Identification of Reading Comprehension Difficulties

    Science.gov (United States)

    Catts, Hugh W.; Nielsen, Diane Corcoran; Bridges, Mindy Sittner; Liu, Yi-Syuan

    2016-01-01

    Most research on early identification of reading disabilities has focused on word reading problems and little attention has been given to reading comprehension difficulties. In this study, we investigated whether measures of language ability and/or response to language intervention in kindergarten uniquely predicted reading comprehension…

  9. Measuring Difficulty in English-Chinese Translation: Towards a General Model of Translation Difficulty

    Science.gov (United States)

    Sun, Sanjun

    2012-01-01

    Accurate assessment of a text's level of translation difficulty is critical for translator training and accreditation, translation research, and the language industry as well. Traditionally, people rely on their general impression to gauge a text's translation difficulty level. If the evaluation process is to be more effective and the…

  10. Memory Abilities in Children with Mathematical Difficulties: Comorbid Language Difficulties Matter

    Science.gov (United States)

    Reimann, Giselle; Gut, Janine; Frischknecht, Marie-Claire; Grob, Alexander

    2013-01-01

    The present study investigated cognitive abilities in children with difficulties in mathematics only (n = 48, M = 8 years and 5 months), combined mathematical and language difficulty (n = 27, M = 8 years and 1 month) and controls (n = 783, M = 7 years and 11 months). Cognitive abilities were measured with seven subtests, tapping visual perception,…

  11. Communication difficulties in teenagers with health impairments

    Directory of Open Access Journals (Sweden)

    Samokhvalova, Anna G.

    2016-09-01

    Full Text Available Contemporary psychological and pedagogical studies pay special attention to the socialization of physically impaired children, inclusive education and methods of providing such children with a safe environment to assist in their development. However, difficulties in interpersonal communication experienced by children with health impairments have remained beyond the research scope. The authors conducted a comparative analysis of communication difficulties in typically developed teenagers aged 12-13 years (n = 100 and the problems faced by their peers with visual (n = 30, auditory (n = 30, speech (n = 25 and motor (n = 15 impairments. Actual communication difficulties in teenagers were studied in two ways: the subjective component of impaired communication was registered through a content analysis of a sentence completion test and the objective manifestations of impaired communication were identified through expert evaluation of children’s communicative behavior (educators and psychologists who had been in close contact with the teenagers acted as experts. First, the authors identified typical standard communication problems that were characteristic of teenagers aged 12-13 years, that is, problems with aggression, tolerance, the ability to admit wrongdoing and make concessions, empathy, self-control, self-analysis and self-expression in communication. Second, typical communication difficulties characteristic of physically impaired children were revealed: failure to understand meaning; feelings of awkwardness and shame of oneself; expectations of a negative attitude toward oneself; gelotophobia; and manifestations of despotism, petulance and egotism as defensive reactions in situations of impaired communication. Third, the authors described specific communication difficulties in teenagers with auditory, visual, speech and motor impairments.

  12. A componential view of children's difficulties in learning fractions

    Science.gov (United States)

    Gabriel, Florence; Coché, Frédéric; Szucs, Dénes; Carette, Vincent; Rey, Bernard; Content, Alain

    2013-01-01

    Fractions are well known to be difficult to learn. Various hypotheses have been proposed in order to explain those difficulties: fractions can denote different concepts; their understanding requires a conceptual reorganization with regard to natural numbers; and using fractions involves the articulation of conceptual knowledge with complex manipulation of procedures. In order to encompass the major aspects of knowledge about fractions, we propose to distinguish between conceptual and procedural knowledge. We designed a test aimed at assessing the main components of fraction knowledge. The test was carried out by fourth-, fifth- and sixth-graders from the French Community of Belgium. The results showed large differences between categories. Pupils seemed to master the part-whole concept, whereas numbers and operations posed problems. Moreover, pupils seemed to apply procedures they do not fully understand. Our results offer further directions to explain why fractions are amongst the most difficult mathematical topics in primary education. This study offers a number of recommendations on how to teach fractions. PMID:24133471

  13. A componential view of children's difficulties in learning fractions.

    Science.gov (United States)

    Gabriel, Florence; Coché, Frédéric; Szucs, Dénes; Carette, Vincent; Rey, Bernard; Content, Alain

    2013-01-01

    Fractions are well known to be difficult to learn. Various hypotheses have been proposed in order to explain those difficulties: fractions can denote different concepts; their understanding requires a conceptual reorganization with regard to natural numbers; and using fractions involves the articulation of conceptual knowledge with complex manipulation of procedures. In order to encompass the major aspects of knowledge about fractions, we propose to distinguish between conceptual and procedural knowledge. We designed a test aimed at assessing the main components of fraction knowledge. The test was carried out by fourth-, fifth- and sixth-graders from the French Community of Belgium. The results showed large differences between categories. Pupils seemed to master the part-whole concept, whereas numbers and operations posed problems. Moreover, pupils seemed to apply procedures they do not fully understand. Our results offer further directions to explain why fractions are amongst the most difficult mathematical topics in primary education. This study offers a number of recommendations on how to teach fractions.

  14. ONKALO POSE experiment. Phase 3: acoustic and ultrasonic monitoring

    International Nuclear Information System (INIS)

    Reyes-Montes, J.; Flynn, W.; Huang, J.

    2014-01-01

    The objectives of the third phase of the POSE experiment are to determine the in situ state of stress at Olkiluoto and the spalling strength of Olkiluoto rock, by internal heating of the experimental hole (ONK-EH3) using 8 vertically installed heaters. This report presents the results from the Acoustic and ultrasonic monitoring carried out around the third experimental hole of the POSE niche between November 2012 and May 2013. The experiment was monitored using an array of 24 transducers installed along 4 monitoring drillholes and data was automatically acquired and processed using the system installed at the niche by Applied Seismology Consultants in May 2012. Daily ultrasonic surveys were carried out between 14 th November 2012 and 21 st May 2013, monitoring the changes in transmission velocities of P and S-waves with an estimated error of ±2 m x s -1 (ASC, 2013). Changes in transmission velocities closely follow the evolution of the temperature profile in the hole wall. An increase in both P-and S-wave transmission velocities is observed at all depth levels and surveyed raypaths during the heating phase, with the highest changes observed in raypaths skimming the hole surface and depths between 2.33 m and 3.7 m. This observation indicates the closure of in situ and excavation-induced microcracks due to thermal stress. After the heaters were switched off, P-wave velocities show a marked decrease, in all raypaths reaching values below those measured at the start of the monitoring approximately 4 weeks after the heaters were switched off. The highest decrease was observed along raypaths surveying the region skimming the hole wall. This decrease below original background values indicates the induction of rock degradation as microcracking induced through the heating-cooling cycle. Changes in P- and S-wave transmission velocity were used to calculate changes in Young's modulus and Poisson's ratio along the different raypaths and depth levels. An overall

  15. Crisis planning to manage risks posed by animal rights extremists.

    Science.gov (United States)

    Bailey, Matthew R; Rich, Barbara A; Bennett, B Taylor

    2010-01-01

    Among the multitude of crises that US research institutions may face are those caused by animal rights activists. While most activists opposed to animal research use peaceful and lawful means of expressing their opinions, some extremists resort to illegal methods. Arson, break-ins, and theft with significant property damage at US animal research facilities began in the 1980s. The most troubling trend to develop in the past decade is the targeting of individuals associated with animal research, whether directly or indirectly, and the use of violent scare tactics to intimidate researchers and their families. The National Association for Biomedical Research has a 30-year history of monitoring the animal rights movement and assisting member institutions with crisis situations. In this article we discuss attacks on researchers at their homes, cyber crimes, exploitation of new media formats, infiltration of research facilities, and the targeting of external research stakeholders and business partners. We describe the need for a well-conceived crisis management plan and strong leadership to mitigate crisis situations. Institutions with well-informed leaders and crisis management teams ready to take timely action are best equipped to protect staff, laboratory animals, and research programs. They act on early warnings, provide support for targeted staff, seek legal remedies, thoughtfully control access to research facilities, and identify and enlist new research supporters. We underscore the importance of up-to-date crisis planning so that institutions are not only aware of ongoing risks posed by animal rights extremists but also better prepared to take preemptive action and able to manage those risks successfully.

  16. Investigation of Problem-Solving and Problem-Posing Abilities of Seventh-Grade Students

    Science.gov (United States)

    Arikan, Elif Esra; Ünal, Hasan

    2015-01-01

    This study aims to examine the effect of multiple problem-solving skills on the problem-posing abilities of gifted and non-gifted students and to assess whether the possession of such skills can predict giftedness or affect problem-posing abilities. Participants' metaphorical images of problem posing were also explored. Participants were 20 gifted…

  17. Cultural adaptations to the differential threats posed by hot versus cold climates.

    Science.gov (United States)

    Murray, Damian R

    2013-10-01

    Hot and cold climates have posed differential threats to human survival throughout history. Cold temperatures can pose direct threats to survival in themselves, whereas hot temperatures may pose threats indirectly through higher prevalence of infectious disease. These differential threats yield convergent predictions for the relationship between more demanding climates and freedom of expression, but divergent predictions for freedom from discrimination.

  18. Single-frame 3D human pose recovery from multiple views

    NARCIS (Netherlands)

    Hofmann, M.; Gavrila, D.M.

    2009-01-01

    We present a system for the estimation of unconstrained 3D human upper body pose from multi-camera single-frame views. Pose recovery starts with a shape detection stage where candidate poses are generated based on hierarchical exemplar matching in the individual camera views. The hierarchy used in

  19. Multi-view 3D Human Pose Estimation in Complex Environment

    NARCIS (Netherlands)

    Hofmann, K.M.; Gavrila, D.M.

    2012-01-01

    We introduce a framework for unconstrained 3D human upper body pose estimation from multiple camera views in complex environment. Its main novelty lies in the integration of three components: single-frame pose recovery, temporal integration and model texture adaptation. Single-frame pose recovery

  20. Children with Speech Difficulties: A survey of clinical practice in the Western Cape

    Directory of Open Access Journals (Sweden)

    Michelle Pascoe

    2010-12-01

    Full Text Available This paper is based on a study by Joffe and Pring (2008 which investigated assessment and therapy methods used by Speech Language Therapists (SLTs in the United Kingdom for children with phonological difficulties. Joffe and Pring reported SLTs’ most favoured assessments and therapy approaches in that context. Children with speech difficulties are likely to form a considerable part of SLT caseloads in South Africa, but the choice of assessments may not be so clearcut given the linguistic diversity of the region and the fact that few assessments have been developed specifically for the SA population. Linked to difficulties with assessment, selection of intervention approaches may also pose challenges. This study aimed to investigate the methods of assessment and intervention used by SLTs in the Western Cape when working with children with speech difficulties. A questionnaire was sent to SLTs working with pre and/ or primary school- aged children. Twenty-nine clinicians of varying experience responded. The majority of SLTs (89% use informal assessment tools in combination with formal assessment. When using formal assessments, more than 50% of SLTs make modifications to better suit the population. Participants use a variety of intervention approaches, often in combination, and based on a child’s individual profile of difficulties and available resources. Forty-six percent of SLTs felt unsure about the selection of assessments and intervention for bi/multilingual children with speech difficulties. SLTs suggested that guidelines about accepted / typical speech development in the region would be helpful for their clinical practice. Clinical implications of the findings are discussed together with some suggestions for developing knowledge of children’s speech difficulties in the South African context.

  1. Managing social, emotional and behavioural difficulties in schools in the Netherlands

    Directory of Open Access Journals (Sweden)

    Ed Smeets

    2009-04-01

    Full Text Available Three key aspects of the school environment are crucial for the prevention and management of social, emotional, and behavioural difficulties (SEBD in schools. These include an adequate instructional environment, a supportive social-emotional climate, and a systematic process of identification and intervention. This paper addresses these critical aspects by presenting results from two studies in primary education in The Netherlands. According to teachers, one in six pupils in mainstream primary schools exhibits some kind of SEBD. Severe cases of aggressive behaviour or ADHD present the greatest difficulties for teachers. The focus in mainstream schools is on the provision of a supportive social-emotional environment and on the identification of SEBD, with little attention to an adequate instructional environment or consistent interventions. This paper describes a systematic approach to the prevention and early intervention of SEBD which will address this issue.

  2. Processes of Learning with Regard to Students’ Learning Difficulties in Mathematics

    Directory of Open Access Journals (Sweden)

    Amalija Zakelj

    2014-06-01

    Full Text Available In the introduction, we write about the process of learning mathematics: the development of mathematical concepts, numerical and spatial imagery on reading and understanding of texts, etc. The central part of the paper is devoted to the study, in which we find that identifying the learning processes associated with learning difficulties of students in mathematics, is not statistically significantly different between primary school teachers and teachers of mathematics. Both groups expose the development of numerical concepts, logical reasoning, and reading and understanding the text as the ones with which difficulties in learning mathematics appear the most frequently. All the processes of learning that the teachers assessed as the ones that represent the greatest barriers to learning have a fairly uniform average estimates of the degree of complexity, ranging from 2.6 to 2.8, which is very close to the estimate makes learning very difficult.

  3. How specific are specific comprehension difficulties?

    DEFF Research Database (Denmark)

    Rønberg, Louise Flensted-Jensen; Petersen, Dorthe Klint

    2016-01-01

    as measured on a phonological coding measure. However, the proportion was smaller than the often reported 10-15 % and even smaller when average sight word recognition was also set as a criterion for word reading ability. Compared to average comprehenders, the poor comprehenders’ sight word recognition......This study explores the occurrence of poor comprehenders, i.e., children identified with reading comprehension difficulties in spite of age-appropriate word reading skills. It supports the findings that some children do show poor reading comprehension in spite of age-appropriate word reading...... and daily reading of literary texts were significantly below that of average readers. This study indicates that a lack of reading experience and, likewise, a lack of fluent word reading may be important factors in understanding nine-year-old poor comprehenders’ difficulties....

  4. EXPLORING STUDENTS‟ DIFFICULTIES IN READING ACADEMIC TEXTS

    Directory of Open Access Journals (Sweden)

    Ira Ernawati

    2017-04-01

    Full Text Available Academic texts play an important role for university students. However, those texts are considered difficult. This study is intended to investigate students‘ difficulties in reading academic texts. The qualitative approach was employed in this study. The design was a case study. The participants were ten students from fifth semester of CLS: EE (Classroom Language and Strategy: Explaining and Exemplifying class who were selected by using purposive sampling. The data were gathered from students‘ journal reflections, observation, and interview. The finding shows that the students encountered reading difficulties in area of textual factors, namely vocabulary, comprehending specific information, text organization, and grammar and human factors including background knowledge, mood, laziness, and time constraint.

  5. Difficulties in radiodiagnosis of children's tumors

    International Nuclear Information System (INIS)

    Kolinova, E.; Zitkova, M.; Suchmova, M.; Jirasek, M.

    1984-01-01

    Some problems of current radiodiagnosis in pediatric oncology are discussed. The main cause of errors in diagnosis and of difficulties barring timely correct diagnosis is the relatively small number of tumors in children and the ensuing lack of knowledge and experience in diagnosis. The situation can only be improved by the disciplined observance of purposeful diagnostic procedures and the centralization of these procedures at specialized departments. (author)

  6. ERRORS AND DIFFICULTIES IN TRANSLATING LEGAL TEXTS

    Directory of Open Access Journals (Sweden)

    Camelia, CHIRILA

    2014-11-01

    Full Text Available Nowadays the accurate translation of legal texts has become highly important as the mistranslation of a passage in a contract, for example, could lead to lawsuits and loss of money. Consequently, the translation of legal texts to other languages faces many difficulties and only professional translators specialised in legal translation should deal with the translation of legal documents and scholarly writings. The purpose of this paper is to analyze translation from three perspectives: translation quality, errors and difficulties encountered in translating legal texts and consequences of such errors in professional translation. First of all, the paper points out the importance of performing a good and correct translation, which is one of the most important elements to be considered when discussing translation. Furthermore, the paper presents an overview of the errors and difficulties in translating texts and of the consequences of errors in professional translation, with applications to the field of law. The paper is also an approach to the differences between languages (English and Romanian that can hinder comprehension for those who have embarked upon the difficult task of translation. The research method that I have used to achieve the objectives of the paper was the content analysis of various Romanian and foreign authors' works.

  7. DIFFICULTY OF AMENDMENT AND INTERPRETATIVE CHOICE

    Directory of Open Access Journals (Sweden)

    Andrew Coan

    2016-01-01

    Full Text Available The extreme difficulty of amending the U.S. Constitution plays a central but largely unexamined role in theoretical debates over interpretive choice. In particular, conventional wisdom assumes that the extreme difficulty of Article V amendment weakens the case for originalism. This view might ultimately be correct, but it is not the freestanding argument against originalism it is often presumed to be. Rather, it depends on contestable normative and empirical premises that require defense. If those premises are wrong, the stringency of Article V might actually strengthen the case for originalism. Or Article V might have no impact on that case one way or another. This “complexity thesis” highlights and clarifies the role that difficulty of amendment plays across a range of significant interpretive debates, including those surrounding writtenness, John Hart Ely’s representation-reinforcement theory, interpretive pluralism, and originalism as a theory of positive law. It also has important implications for the under-studied relations between statutory and constitutional interpretation and federal and state constitutional interpretation.

  8. Feeding Difficulties in Children with Esophageal Atresia.

    Science.gov (United States)

    Mahoney, Lisa; Rosen, Rachel

    2016-06-01

    The current available literature evaluating feeding difficulties in children with esophageal atresia was reviewed. The published literature was searched through PubMed using a pre-defined search strategy. Feeding difficulties are commonly encountered in children and adults with repaired esophageal atresia [EA]. The mechanism for abnormal feeding includes both esophageal and oropharyngeal dysphagia. Esophageal dysphagia is commonly reported in patients with EA and causes include dysmotility, anatomic lesions, esophageal outlet obstruction and esophageal inflammation. Endoscopic evaluation, esophageal manometry and esophograms can be useful studies to evaluate for causes of esophageal dysphagia. Oropharyngeal dysfunction and aspiration are also important mechanisms for feeding difficulties in patients with EA. These patients often present with respiratory symptoms. Videofluoroscopic swallow study, salivagram, fiberoptic endoscopic evaluation of swallowing and high-resolution manometry can all be helpful tools to identify aspiration. Once diagnosed, management goals include reduction of aspiration during swallowing, reducing full column reflux into the oropharynx and continuation of oral feeding to maintain skills. We review specific strategies which can be used to reduce aspiration of gastric contents, including thickening feeds, changing feeding schedule, switching formula, trialing transpyloric feeds and fundoplication. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. Nocturia is the Lower Urinary Tract Symptom With Greatest Impact on Quality of Life of Men From a Community Setting

    Directory of Open Access Journals (Sweden)

    Eduardo de Paula Miranda

    2014-06-01

    Full Text Available PurposeLower urinary tract symptoms are numerous, but the specific impact of each of these symptoms on the quality of life (QoL has not been evaluated in community-dwelling men. An assessment of these symptoms and their effects on QoL was the focus of this study.MethodsWe performed a cross-sectional study with 373 men aged >50 years from a community setting. Patients completed the International Prostate Symptom Score questionnaire, which includes questions on each of the specific urinary symptoms and a question addressing health-related QoL that are graded from 0 to 5. We used the Pearson correlation test to assess the impact of each symptom on QoL.ResultsNocturia (58.9% was the most prevalent urinary symptom. The mean score was 0.9±1.4 for incomplete emptying, 1.0±1.5 for frequency, 0.9±1.3 for intermittency, 0.8±1.3 for urgency, 1.0±1.5 for weak stream, 0.5±1.0 for straining, and 2.0±1.6 for nocturia. Nocturia and frequency were the only symptoms associated with poorer QoL, with nocturia showing a stronger association.ConclusionsNocturia affects 50% of community dwelling men aged >50 years, and is the lower urinary tract symptom with the greatest negative impact on QoL.

  10. Special needs children with speech and hearing difficulties: prevalence and unmet needs.

    Science.gov (United States)

    Kenney, Mary Kay; Kogan, Michael D

    2011-01-01

    The purpose of this study was to establish prevalences and sociodemographic characteristics associated with parent-reported speech and hearing difficulties among children with special health care needs (CSHCN); determine unmet needs for therapy, hearing aids, and communication devices; and examine the association between unmet needs and resources such as health insurance, early intervention/special education, and a medical home. Data were analyzed for 300,910 children without special health care needs and 40,723 CSHCN from the 2005-2006 National Survey of Children with Special Health Care Needs. Prevalence, sociodemographic characteristics, and unmet needs for 7132 CSHCN with speech difficulties and 1982 CSHCN with hearing difficulties were assessed. Logistic regression was used to determine the associations between unmet needs for therapy or hearing/communication devices and resources for addressing needs for therapy, hearing, and communication aids. The parent-reported prevalence of speech difficulty among CSHCN in the general population was 2.9% and approximately 20% among all CSHCN, in contrast to the lower prevalence of hearing difficulty (0.7% and 5%, respectively). Relative unmet need was greatest for communication devices and least for hearing aids. The strongest association with reducing unmet needs was having a medical home, and the most significant aspect of medical home was having effective care coordination. Having a medical home is significantly associated with fewer unmet needs for therapy and hearing/communication devices among CSHCN with speech and hearing difficulties. Care coordination may constitute an important factor that allows the primary care provider to link with services that CSHCN with communication problems require. Published by Elsevier Inc.

  11. Modelling Question Difficulty in an A Level Physics Examination

    Science.gov (United States)

    Crisp, Victoria; Grayson, Rebecca

    2013-01-01

    "Item difficulty modelling" is a technique used for a number of purposes such as to support future item development, to explore validity in relation to the constructs that influence difficulty and to predict the difficulty of items. This research attempted to explore the factors influencing question difficulty in a general qualification…

  12. When the most potent combination of antibiotics selects for the greatest bacterial load: the smile-frown transition.

    Directory of Open Access Journals (Sweden)

    Rafael Pena-Miller

    Full Text Available Conventional wisdom holds that the best way to treat infection with antibiotics is to 'hit early and hit hard'. A favoured strategy is to deploy two antibiotics that produce a stronger effect in combination than if either drug were used alone. But are such synergistic combinations necessarily optimal? We combine mathematical modelling, evolution experiments, whole genome sequencing and genetic manipulation of a resistance mechanism to demonstrate that deploying synergistic antibiotics can, in practice, be the worst strategy if bacterial clearance is not achieved after the first treatment phase. As treatment proceeds, it is only to be expected that the strength of antibiotic synergy will diminish as the frequency of drug-resistant bacteria increases. Indeed, antibiotic efficacy decays exponentially in our five-day evolution experiments. However, as the theory of competitive release predicts, drug-resistant bacteria replicate fastest when their drug-susceptible competitors are eliminated by overly-aggressive treatment. Here, synergy exerts such strong selection for resistance that an antagonism consistently emerges by day 1 and the initially most aggressive treatment produces the greatest bacterial load, a fortiori greater than if just one drug were given. Whole genome sequencing reveals that such rapid evolution is the result of the amplification of a genomic region containing four drug-resistance mechanisms, including the acrAB efflux operon. When this operon is deleted in genetically manipulated mutants and the evolution experiment repeated, antagonism fails to emerge in five days and antibiotic synergy is maintained for longer. We therefore conclude that unless super-inhibitory doses are achieved and maintained until the pathogen is successfully cleared, synergistic antibiotics can have the opposite effect to that intended by helping to increase pathogen load where, and when, the drugs are found at sub-inhibitory concentrations.

  13. When the most potent combination of antibiotics selects for the greatest bacterial load: the smile-frown transition.

    Science.gov (United States)

    Pena-Miller, Rafael; Laehnemann, David; Jansen, Gunther; Fuentes-Hernandez, Ayari; Rosenstiel, Philip; Schulenburg, Hinrich; Beardmore, Robert

    2013-01-01

    Conventional wisdom holds that the best way to treat infection with antibiotics is to 'hit early and hit hard'. A favoured strategy is to deploy two antibiotics that produce a stronger effect in combination than if either drug were used alone. But are such synergistic combinations necessarily optimal? We combine mathematical modelling, evolution experiments, whole genome sequencing and genetic manipulation of a resistance mechanism to demonstrate that deploying synergistic antibiotics can, in practice, be the worst strategy if bacterial clearance is not achieved after the first treatment phase. As treatment proceeds, it is only to be expected that the strength of antibiotic synergy will diminish as the frequency of drug-resistant bacteria increases. Indeed, antibiotic efficacy decays exponentially in our five-day evolution experiments. However, as the theory of competitive release predicts, drug-resistant bacteria replicate fastest when their drug-susceptible competitors are eliminated by overly-aggressive treatment. Here, synergy exerts such strong selection for resistance that an antagonism consistently emerges by day 1 and the initially most aggressive treatment produces the greatest bacterial load, a fortiori greater than if just one drug were given. Whole genome sequencing reveals that such rapid evolution is the result of the amplification of a genomic region containing four drug-resistance mechanisms, including the acrAB efflux operon. When this operon is deleted in genetically manipulated mutants and the evolution experiment repeated, antagonism fails to emerge in five days and antibiotic synergy is maintained for longer. We therefore conclude that unless super-inhibitory doses are achieved and maintained until the pathogen is successfully cleared, synergistic antibiotics can have the opposite effect to that intended by helping to increase pathogen load where, and when, the drugs are found at sub-inhibitory concentrations.

  14. Pain is the Greatest Preoperative Concern for Patients and Parents Before Posterior Spinal Fusion for Adolescent Idiopathic Scoliosis.

    Science.gov (United States)

    Chan, Priscella; Skaggs, David L; Sanders, Austin E; Villamor, Gabriela A; Choi, Paul D; Tolo, Vernon T; Andras, Lindsay M

    2017-11-01

    Prospective cross-sectional study. To evaluate patients' and parents' concerns so they can be addressed with appropriate preoperative counseling. Despite much research on outcomes for posterior spinal fusion (PSF) in adolescent idiopathic scoliosis (AIS), little is available about preoperative fears or concerns. Patients with AIS undergoing PSF, their parents, and surgeons were prospectively enrolled and asked to complete a survey on their fears and concerns about surgery at their preoperative appointment. Forty-eight patients and parents completed surveys. Four attending pediatric spine surgeons participated and submitted 48 responses. Mean age of patients was 14.2 years. On a scale of 0 to 10, mean level of concern reported by parents (6.9) was higher than that reported by patients (4.6). Surgeons rated the procedure's complexity on a scale of 0 to 10 and reported a mean of 5.2. Neither patients' nor parents' level of concern correlated with the surgeons' assessment of the procedure's complexity level (R = 0.19 and 0.12, P = 0.20 and P = 0.42, respectively). Top three concerns for patients were pain (25%), ability to return to activities (21%), and neurologic injury (17%). Top three concerns for parents were pain (35%), neurologic injury (21%), and amount of correction (17%). Top three concerns for surgeons were postoperative shoulder balance (44%), neurologic injury (27%), and lowest instrumented vertebrae selection (27%). Patients reported the same concerns 23% of the time as parents, and 17% of the time as surgeons. Parents and surgeons reported the same concerns 21% of the time. Pain was the greatest concern for both patients and parents but was rarely listed as a concern by surgeons. Parent and patient level of concern did not correlate to the surgeon's assessment of the procedure's complexity. Neurologic injury was a top concern for all groups, but otherwise there was little overlap between physician, patient, and parent concerns. 3.

  15. Creativity of Field-dependent and Field-independent Students in Posing Mathematical Problems

    Science.gov (United States)

    Azlina, N.; Amin, S. M.; Lukito, A.

    2018-01-01

    This study aims at describing the creativity of elementary school students with different cognitive styles in mathematical problem-posing. The posed problems were assessed based on three components of creativity, namely fluency, flexibility, and novelty. The free-type problem posing was used in this study. This study is a descriptive research with qualitative approach. Data collections were conducted through written task and task-based interviews. The subjects were two elementary students. One of them is Field Dependent (FD) and the other is Field Independent (FI) which were measured by GEFT (Group Embedded Figures Test). Further, the data were analyzed based on creativity components. The results show thatFD student’s posed problems have fulfilled the two components of creativity namely fluency, in which the subject posed at least 3 mathematical problems, and flexibility, in whichthe subject posed problems with at least 3 different categories/ideas. Meanwhile,FI student’s posed problems have fulfilled all three components of creativity, namely fluency, in which thesubject posed at least 3 mathematical problems, flexibility, in which thesubject posed problems with at least 3 different categories/ideas, and novelty, in which the subject posed problems that are purely the result of her own ideas and different from problems they have known.

  16. Point Cloud Based Relative Pose Estimation of a Satellite in Close Range

    Directory of Open Access Journals (Sweden)

    Lujiang Liu

    2016-06-01

    Full Text Available Determination of the relative pose of satellites is essential in space rendezvous operations and on-orbit servicing missions. The key problems are the adoption of suitable sensor on board of a chaser and efficient techniques for pose estimation. This paper aims to estimate the pose of a target satellite in close range on the basis of its known model by using point cloud data generated by a flash LIDAR sensor. A novel model based pose estimation method is proposed; it includes a fast and reliable pose initial acquisition method based on global optimal searching by processing the dense point cloud data directly, and a pose tracking method based on Iterative Closest Point algorithm. Also, a simulation system is presented in this paper in order to evaluate the performance of the sensor and generate simulated sensor point cloud data. It also provides truth pose of the test target so that the pose estimation error can be quantified. To investigate the effectiveness of the proposed approach and achievable pose accuracy, numerical simulation experiments are performed; results demonstrate algorithm capability of operating with point cloud directly and large pose variations. Also, a field testing experiment is conducted and results show that the proposed method is effective.

  17. Cross-cultural acceptability and utility of the strengths and difficulties questionnaire: views of families

    Directory of Open Access Journals (Sweden)

    Paula Kersten

    2016-10-01

    Full Text Available Abstract Background Screening children for behavioural difficulties requires the use of a tool that is culturally valid. We explored the cross-cultural acceptability and utility of the Strengths and Difficulties Questionnaire for pre-school children (aged 3–5 as perceived by families in New Zealand. Methods A qualitative interpretive descriptive study (focus groups and interviews in which 65 participants from five key ethnic groups (New Zealand European, Māori, Pacific, Asian and other immigrant parents took part. Thematic analysis using an inductive approach, in which the themes identified are strongly linked to the data, was employed. Results Many parents reported they were unclear about the purpose of the tool, affecting its perceived value. Participants reported not understanding the context in which they should consider the questions and had difficulty understanding some questions and response options. Māori parents generally did not support the questionnaire based approach, preferring face to face interaction. Parents from Māori, Pacific Island, Asian, and new immigrant groups reported the tool lacked explicit consideration of children in their cultural context. Parents discussed the importance of timing and multiple perspectives when interpreting scores from the tool. Conclusions In summary, this study posed a number of challenges to the use of the Strengths and Difficulties Questionnaire in New Zealand. Further work is required to develop a tool that is culturally appropriate with good content validity.

  18. Cross-cultural acceptability and utility of the strengths and difficulties questionnaire: views of families.

    Science.gov (United States)

    Kersten, Paula; Dudley, Margaret; Nayar, Shoba; Elder, Hinemoa; Robertson, Heather; Tauroa, Robyn; McPherson, Kathryn M

    2016-10-12

    Screening children for behavioural difficulties requires the use of a tool that is culturally valid. We explored the cross-cultural acceptability and utility of the Strengths and Difficulties Questionnaire for pre-school children (aged 3-5) as perceived by families in New Zealand. A qualitative interpretive descriptive study (focus groups and interviews) in which 65 participants from five key ethnic groups (New Zealand European, Māori, Pacific, Asian and other immigrant parents) took part. Thematic analysis using an inductive approach, in which the themes identified are strongly linked to the data, was employed. Many parents reported they were unclear about the purpose of the tool, affecting its perceived value. Participants reported not understanding the context in which they should consider the questions and had difficulty understanding some questions and response options. Māori parents generally did not support the questionnaire based approach, preferring face to face interaction. Parents from Māori, Pacific Island, Asian, and new immigrant groups reported the tool lacked explicit consideration of children in their cultural context. Parents discussed the importance of timing and multiple perspectives when interpreting scores from the tool. In summary, this study posed a number of challenges to the use of the Strengths and Difficulties Questionnaire in New Zealand. Further work is required to develop a tool that is culturally appropriate with good content validity.

  19. On the study and difficulties of mathematics

    CERN Document Server

    De Morgan, Augustus

    2005-01-01

    One of the twentieth century's most eminent mathematical writers, Augustus De Morgan enriched his expositions with insights from history and psychology. On the Study and Difficulties of Mathematics represents some of his best work, containing points usually overlooked by elementary treatises, and written in a fresh and natural tone that provides a refreshing contrast to the mechanical character of common textbooks.Presuming only a knowledge of the rules of algebra and Euclidean theorems, De Morgan begins with some introductory remarks on the nature and objects of mathematics. He discusses the

  20. NECCESITY AND DIFFICULTY OF R D PERFORMANCEMEASUREMENT

    Directory of Open Access Journals (Sweden)

    MariaFekete-Farkas

    2012-07-01

    Full Text Available We are living in a globalized world with increasing population which is facingsevere global economic and financial crises as well as serious environmentalproblems. The possibilities to overcome these difficulties can be interpreted asthe need for sustainable development calling for innovation, increased R Dspending with increased R D effectiveness and efficiency. Besides greaterattentionforthe need of deeper understanding of the innovation process and therole of R D in it, this paper has discussed the many analytical problems thatconfront a researcher in this area, and additionally calls for research oncollaboration between universities and industry. Among other conclusions thispaper also provides a new way of thinking for policy makers and performancemonitoring committees.

  1. [IgE myeloma. Laboratory typing difficulties].

    Science.gov (United States)

    Bovone, Nora S; Fuente, María Cristina; Gastiazoro, Ana María; Alfonso, Graciela; Freitas, María Josefina

    2014-01-01

    The IgE multiple myeloma is a rare neoplasm of plasma cell accounting for 0.01% of all plasma cell dyscrasias. They are generally of more aggressive development and to date there are no more than 50 cases published in current literature. Laboratory studies are, in these cases, essential for the classification of the monoclonal component in serum and urine. The aim of this presentation is to report a patient diagnosed with IgE myeloma and to point out that the laboratory difficulties noted in these rare cases can lead to an erroneous report.

  2. Intervention program efficacy for spelling difficulties.

    Science.gov (United States)

    Sampaio, Maria Nobre; Capellini, Simone Aparecida

    2014-01-01

    To develop an intervention procedure for spelling difficulties and to verify the effectiveness of the intervention program in students with lower spelling performance. We developed an intervention program for spelling difficulties, according to the semiology of the errors. The program consisted of three modules totaling 16 sessions. The study included 40 students of the third to fifth grade of public elementary education of the city of Marilia (SP), of both genders, in aged of eight to 12 years old, being distributed in the following groups: GI (20 students with lower spelling performance) and GII (20 students with higher spelling performance). In situation of pre and post-testing, all groups were submitted to the Pro-Orthography. The results statistically analyzed showed that, in general, all groups had average of right that has higher in post-testing, reducing the types of errors second semiologycal classification, mainly related to natural spelling errors. However, the results also showed that the groups submitted to the intervention program showed better performance on spelling tests in relation to not submitted. The intervention program developed was effective once the groups submitted showed better performance on spelling tests in relation to not submitted. Therefore, the intervention program can help professionals in the Health and Education to minimize the problems related to spelling, giving students an intervention that is effective for the development of the spelling knowledge.

  3. Maternal worries, home safety behaviors, and perceived difficulties.

    Science.gov (United States)

    Hendrickson, Sherry Garrett

    2008-01-01

    The aim of the study was to explore the worries, safety behaviors, and perceived difficulties in keeping children safe at home in a purposive sample of low-income, predominantly non-English speaking mothers as a foundation for later nursing interventions. This study was a qualitative, descriptive design with content analysis to identify maternal concerns, behaviors, and perceptions of home safety as part of a larger study. Eighty-two mothers, 64% of whom were monolingual Spanish-speakers, responded in writing to three semistructured interview questions. When mothers were unable to read and write the researcher wrote the responses, then read the content aloud for verification. A standardized probe for each question was posed to obtain richer responses. Data management included use of the software program NUD*IST and coding analyses following the Miles and Huberman guidelines (1994). Interpretations were translated into English for this report. The major worries were falling, health, kidnapping, and being hit by a car. The leading maternal behaviors were coded as being physically, verbally, and environmentally preventive. Mothers said that it was their role to provide safety, and that this role could be wearisome, such that constant supervision was difficult. Low-income mothers described their worries for their 1 to 4 year-old children, explored their behaviors for preventing injury, and discussed what made keeping children from harm difficult. Understanding how mothers keep children safe, the barriers to home safety, and effective safety behaviors are important to the health of children. The clinical relevance of this study includes building trust as clinicians plan assessment, intervention and evaluation of home safety to encourage dialog about concerns, safety behaviors, and barriers to keeping children from injury.

  4. Maximising the effect of combination HIV prevention through prioritisation of the people and places in greatest need: a modelling study.

    Science.gov (United States)

    Anderson, Sarah-Jane; Cherutich, Peter; Kilonzo, Nduku; Cremin, Ide; Fecht, Daniela; Kimanga, Davies; Harper, Malayah; Masha, Ruth Laibon; Ngongo, Prince Bahati; Maina, William; Dybul, Mark; Hallett, Timothy B

    2014-07-19

    Epidemiological data show substantial variation in the risk of HIV infection between communities within African countries. We hypothesised that focusing appropriate interventions on geographies and key populations at high risk of HIV infection could improve the effect of investments in the HIV response. With use of Kenya as a case study, we developed a mathematical model that described the spatiotemporal evolution of the HIV epidemic and that incorporated the demographic, behavioural, and programmatic differences across subnational units. Modelled interventions (male circumcision, behaviour change communication, early antiretoviral therapy, and pre-exposure prophylaxis) could be provided to different population groups according to their risk behaviours or their location. For a given national budget, we compared the effect of a uniform intervention strategy, in which the same complement of interventions is provided across the country, with a focused strategy that tailors the set of interventions and amount of resources allocated to the local epidemiological conditions. A uniformly distributed combination of HIV prevention interventions could reduce the total number of new HIV infections by 40% during a 15-year period. With no additional spending, this effect could be increased by 14% during the 15 years-almost 100,000 extra infections, and result in 33% fewer new HIV infections occurring every year by the end of the period if the focused approach is used to tailor resource allocation to reflect patterns in local epidemiology. The cumulative difference in new infections during the 15-year projection period depends on total budget and costs of interventions, and could be as great as 150,000 (a cumulative difference as great as 22%) under different assumptions about the unit costs of intervention. The focused approach achieves greater effect than the uniform approach despite exactly the same investment. Through prioritisation of the people and locations at greatest

  5. Posts, pics, or polls? Which post type generates the greatest engagement in a Facebook physical activity intervention?

    Science.gov (United States)

    Edney, Sarah; Looyestyn, Jemma; Ryan, Jillian; Kernot, Jocelyn; Maher, Carol

    2018-04-05

    Social networking websites have attracted considerable attention as a delivery platform for physical activity interventions. Current evidence highlights a need to enhance user engagement with these interventions to actualize their potential. The purpose of this study was to determine which post type generates the most engagement from participants and whether engagement was related to change in physical activity in an intervention delivered via Facebook. Subgroup analysis of the intervention condition of a randomized controlled trial was conducted. The group moderator posted a new message to the private Facebook group each day of the program. The Facebook posts (n = 118) were categorized into the following types: moderator-initiated running program, multimedia, motivational, opinion polls, or discussion question and participant-initiated experience shares, or questions. Four metrics were used to measure volume of engagement with each post type, "likes," "comments," "poll votes," and "photo uploads." One-way ANOVA was used to determine whether engagement differed by post type and an independent samples t-test to determine differences in engagement between moderator and participant-initiated posts. Pearson correlation was used to examine associations between total engagement and change in physical activity. Engagement varied by post type. Polls elicited the greatest engagement (p ≤ .01). The most common form of engagement was "likes," and engagement was higher for moderator-initiated rather than participant-initiated posts (mean = 8.0 [SD 6.8] vs. 5.3 [SD 3.2]; p ≤ .01). Total engagement with the Facebook group was not directly associated with change in physical activity (r = -.13, p = .47). However, engagement was associated with compliance with the running program (r = .37, p = .04) and there was a nonsignificant positive association between compliance and change in physical activity (r = .32, p = .08). Posts requiring a simple response generated the most

  6. Perbedaan Keterampilan Pemecahan Masalah pada Pembelajaran Fisika Menggunakan Metode Problem Posing dan Problem Solving

    OpenAIRE

    Rahman, Adetya; Hartini, Sri; An'nur, Syubhan

    2015-01-01

    Teachers should be able to choose the method of learning that can help students in learning physics, namely the method of problem posing and problem solving method. The purposes of this study are : (1) describe the learning physics skills by using problem posing method, (2) describe the learning physics skills by using problem solving method, and (3) know difference between learning physics skills by using problem posing method and problem solving method in class XI of Science SMAN 6 Banjarma...

  7. Teach it Yourself - Fast Modeling of Industrial Objects for 6D Pose Estimation

    DEFF Research Database (Denmark)

    Sølund, Thomas; Rajeeth Savarimuthu, Thiusius; Glent Buch, Anders

    2015-01-01

    In this paper, we present a vision system that allows a human to create new 3D models of novel industrial parts by placing the part in two different positions in the scene. The two shot modeling framework generates models with a precision that allows the model to be used for 6D pose estimation wi....... In addition, the models are applied in a pose estimation application, evaluated with 37 different scenes with 61 unique object poses. The pose estimation results show a mean translation error on 4.97 mm and a mean rotation error on 3.38 degrees....

  8. Parents' difficulties with decisions about childhood immunisation.

    Science.gov (United States)

    Austin, Helen; Campion-Smith, Charles; Thomas, Sarah; Ward, William

    2008-10-01

    Uptake of childhood immunisation fluctuates in the UK. Convenience, access and parents' relationships with professionals influence uptake. This study explores the decision-making by parents about their children's immunisation through focus groups with analysis to identify categories of concern. Issues raised in focus groups included fear, risk, anger, worry and guilt, confusion, difficulty of decision-making and trust of professionals. The parents of completely and incompletely immunised children shared areas of concern, but there were also significant differences. There was a subset of parents of incompletely immunised children who had decided that their children would not have full immunisation, and this group had little trust in information provided by healthcare professionals. Simply providing more information is unlikely to change their decision.

  9. Regulatory difficulties in a developing country

    International Nuclear Information System (INIS)

    Jacobs, W.R. Jr.

    1978-01-01

    The regulatory agency assigned the task of regulating the initial entry into the field of nuclear power generation by a developing country has a very difficult job. Based on the authors' experience during the start-up and initial operation of Ko-Ri Unit I, the first power reactor in the Republic of Korea, observations on regulatory difficulties and recommendations for improved regulatory effectiveness are offered. The problem areas can be loosely grouped into three general categories: (1) Lack of adequate technical knowledge which is the basis for all effective regulation; (2) Difficulties with understanding and utilization of the required regulatory documentation; (3) Failure to establish the proper regulatory environment. Examples are cited from actual experience during the Ko-Ri Unit I start-up to demonstrate the impact that regulatory activities can have on a plant construction and testing programme. The problems encountered are not unique to developing countries but also exist in the United States of America. Recommendations are offered which should be beneficial to either newly formed regulatory agencies or agencies wishing to improve their abilities and effectiveness. These include: (1) Additional training of regulatory inspectors in plant operations; (2) Additional experience gained by participation in regulatory activities in other countries; (3) Increased attention given to regulatory documents, especially plant technical specifications; (4) Establishment of formal lines of communication between the utility and the regulatory agency; (5) Clear definition of regulatory responsibilities to avoid areas of overlapping jurisdiction; (6) Active participation by the regulatory staff very early in the project. It is hoped that these and other recommendations offered will greatly improve regulatory effectiveness and at the same time demonstrate that when the decision is made to 'go nuclear', a strong commitment must be made to develop and support a technically

  10. Relationship of cognitive function and adjustment difficulties among children and adolescents with dissociative disorder.

    Science.gov (United States)

    Ranjan, Rajeev; Mehta, Manju; Sagar, Rajesh; Sarkar, Siddharth

    2016-01-01

    Although it has been suggested that children and adolescents with dissociative disorder have some cognitive deficits, the association of these cognitive impairments with adjustment difficulties has not been evaluated. The present study aimed to assess the relationship between cognitive functioning and adjustment difficulties in children and adolescents with dissociative disorder. This cross-sectional, descriptive assessment was carried out in the outpatient setting of child and adolescent psychiatric service in a tertiary care hospital. Fifty newly diagnosed children and adolescents with dissociative disorder were included. The cognitive functions were assessed by varied neuropsychological tests, and Bell's adjustment inventory was used for assessing various domains of adjustment. The mean age of the sample which comprised 40% males was 13.0 (±2.4) years. The mean intelligence quotient (IQ) of the sample was 90.6. Impairment in cognitive test was maximum for verbal working memory followed by sustained attention, visual learning and memory, and verbal retention and recall. Adjustment difficulties were greatest in the domains of self, followed by domains of health, school, and family. Significant association was found between the IQ and adjustment in school; visual learning and memory and adjustments in school and overall adjustment; and sustained attention and adjustment of health. Dissociative children have poor cognitive ability which may be related to poor adjustment scores.

  11. Relationship of cognitive function and adjustment difficulties among children and adolescents with dissociative disorder

    Directory of Open Access Journals (Sweden)

    Rajeev Ranjan

    2016-01-01

    Full Text Available Background and Aims: Although it has been suggested that children and adolescents with dissociative disorder have some cognitive deficits, the association of these cognitive impairments with adjustment difficulties has not been evaluated. The present study aimed to assess the relationship between cognitive functioning and adjustment difficulties in children and adolescents with dissociative disorder. Methods: This cross-sectional, descriptive assessment was carried out in the outpatient setting of child and adolescent psychiatric service in a tertiary care hospital. Fifty newly diagnosed children and adolescents with dissociative disorder were included. The cognitive functions were assessed by varied neuropsychological tests, and Bell's adjustment inventory was used for assessing various domains of adjustment. Results: The mean age of the sample which comprised 40% males was 13.0 (±2.4 years. The mean intelligence quotient (IQ of the sample was 90.6. Impairment in cognitive test was maximum for verbal working memory followed by sustained attention, visual learning and memory, and verbal retention and recall. Adjustment difficulties were greatest in the domains of self, followed by domains of health, school, and family. Significant association was found between the IQ and adjustment in school; visual learning and memory and adjustments in school and overall adjustment; and sustained attention and adjustment of health. Conclusions: Dissociative children have poor cognitive ability which may be related to poor adjustment scores.

  12. Making 2D face recognition more robust using AAMs for pose compensation

    NARCIS (Netherlands)

    Huisman, Peter; Munster, Ruud; Moro-Ellenberger, Stephanie; Veldhuis, Raymond N.J.; Bazen, A.M.

    2006-01-01

    The problem of pose in 2D face recognition is widely acknowledged. Commercial systems are limited to near frontal face images and cannot deal with pose deviations larger than 15 degrees from the frontal view. This is a problem, when using face recognition for surveillance applications in which

  13. Integrating Worked Examples into Problem Posing in a Web-Based Learning Environment

    Science.gov (United States)

    Hsiao, Ju-Yuan; Hung, Chun-Ling; Lan, Yu-Feng; Jeng, Yoau-Chau

    2013-01-01

    Most students always lack of experience and perceive difficult regarding problem posing. The study hypothesized that worked examples may have benefits for supporting students' problem posing activities. A quasi-experiment was conducted in the context of a business mathematics course for examining the effects of integrating worked examples into…

  14. Analyzing Pre-Service Primary Teachers' Fraction Knowledge Structures through Problem Posing

    Science.gov (United States)

    Kilic, Cigdem

    2015-01-01

    In this study it was aimed to determine pre-service primary teachers' knowledge structures of fraction through problem posing activities. A total of 90 pre-service primary teachers participated in this study. A problem posing test consisting of two questions was used and the participants were asked to generate as many as problems based on the…

  15. An Investigation of Eighth Grade Students' Problem Posing Skills (Turkey Sample)

    Science.gov (United States)

    Arikan, Elif Esra; Ünal, Hasan

    2015-01-01

    To pose a problem refers to the creative activity for mathematics education. The purpose of the study was to explore the eighth grade students' problem posing ability. Three learning domains such as requiring four operations, fractions and geometry were chosen for this reason. There were two classes which were coded as class A and class B. Class A…

  16. Body-part templates for recovery of 2D human poses under occlusion

    NARCIS (Netherlands)

    Poppe, Ronald Walter; Poel, Mannes; Perales, F.J.; Fisher, R.B.

    2008-01-01

    Detection of humans and estimation of their 2D poses from a single image are challenging tasks. This is especially true when part of the observation is occluded. However, given a limited class of movements, poses can be recovered given the visible body-parts. To this end, we propose a novel template

  17. Teachers Implementing Mathematical Problem Posing in the Classroom: Challenges and Strategies

    Science.gov (United States)

    Leung, Shuk-kwan S.

    2013-01-01

    This paper reports a study about how a teacher educator shared knowledge with teachers when they worked together to implement mathematical problem posing (MPP) in the classroom. It includes feasible methods for getting practitioners to use research-based tasks aligned to the curriculum in order to encourage children to pose mathematical problems.…

  18. Problem-Posing in Education: Transformation of the Practice of the Health Professional.

    Science.gov (United States)

    Casagrande, L. D. R.; Caron-Ruffino, M.; Rodrigues, R. A. P.; Vendrusculo, D. M. S.; Takayanagui, A. M. M.; Zago, M. M. F.; Mendes, M. D.

    1998-01-01

    Studied the use of a problem-posing model in health education. The model based on the ideas of Paulo Freire is presented. Four innovative experiences of teaching-learning in environmental and occupational health and patient education are reported. Notes that the problem-posing model has the capability to transform health-education practice.…

  19. The Effects of Problem Posing on Student Mathematical Learning: A Meta-Analysis

    Science.gov (United States)

    Rosli, Roslinda; Capraro, Mary Margaret; Capraro, Robert M.

    2014-01-01

    The purpose of the study was to meta-synthesize research findings on the effectiveness of problem posing and to investigate the factors that might affect the incorporation of problem posing in the teaching and learning of mathematics. The eligibility criteria for inclusion of literature in the meta-analysis was: published between 1989 and 2011,…

  20. Tooth display and lip position during spontaneous and posed smiling in adults.

    Science.gov (United States)

    Van Der Geld, Pieter; Oosterveld, Paul; Berge, Stefaan J; Kuijpers-Jagtman, Anne M

    2008-08-01

    To analyze differences in tooth display, lip-line height, and smile width between the posed smiling record, traditionally produced for orthodontic diagnosis, and the spontaneous (Duchenne) smile of joy. The faces of 122 male participants were each filmed during spontaneous and posed smiling. Spontaneous smiles were elicited through the participants watching a comical movie. Maxillary and mandibular lip-line heights, tooth display, and smile width were measured using a digital videographic method for smile analysis. Paired sample t-tests were used to compare measurements of posed and spontaneous smiling. Maxillary lip-line heights during spontaneous smiling were significantly higher than during posed smiling. Compared to spontaneous smiling, tooth display in the (pre)molar area during posed smiling decreased by up to 30%, along with a significant reduction of smile width. During posed smiling, also mandibular lip-line heights changed and the teeth were more covered by the lower lip than during spontaneous smiling. Reduced lip-line heights, tooth display, and smile width on a posed smiling record can have implications for the diagnostics of lip-line height, smile arc, buccal corridors, and plane of occlusion. Spontaneous smiling records next to posed smiling records are therefore recommended for diagnostic purposes. Because of the dynamic nature of spontaneous smiling, it is proposed to switch to dynamic video recording of the smile.

  1. Why doctors have difficulty with sex histories.

    Science.gov (United States)

    Merrill, J M; Laux, L F; Thornby, J I

    1990-06-01

    Studies have shown that physicians' performance has not been as good as it should be in detecting sexually transmitted diseases (STDs) and in counseling patients about their transmission. The AIDS pandemic has underscored the need to find out why this is true. In our study, we identified the major reasons physicians believe other doctors fail to take adequate sex histories. Scales were then developed to measure the three principal reasons given by these physicians: embarrassment, belief that the sex history is not relevant to the patient's chief complaint, and belief by the physicians that they are not adequately trained. When 350 senior medical students were surveyed, 93% thought that knowledge of a patient's sexual practices is an important part of their patient's medical history, but 50% felt poorly trained to take this history and 25% felt embarrassed to ask the necessary questions. To learn why some students score well on these three dimensions and others do not, a limited number of personal attributes were measured and correlated with the scores on these three measures. Shyness and social anxiety as a personal trait predicted which student was most likely to experience embarrassment in taking a sex history. A nonsympathetic view of patients' psychosocial problems was the variable most closely related to the belief that the sex history was of little importance in understanding a patient's problem. Students who believed this most strongly were the same ones who were most homophobic, authoritarian, and had the greatest fear of AIDS infection. The sense of not feeling adequately trained to take a sex history related most strongly to low self-esteem. How these barriers to STD risk assessment might be overcome is discussed.

  2. Coupled bias-variance tradeoff for cross-pose face recognition.

    Science.gov (United States)

    Li, Annan; Shan, Shiguang; Gao, Wen

    2012-01-01

    Subspace-based face representation can be looked as a regression problem. From this viewpoint, we first revisited the problem of recognizing faces across pose differences, which is a bottleneck in face recognition. Then, we propose a new approach for cross-pose face recognition using a regressor with a coupled bias-variance tradeoff. We found that striking a coupled balance between bias and variance in regression for different poses could improve the regressor-based cross-pose face representation, i.e., the regressor can be more stable against a pose difference. With the basic idea, ridge regression and lasso regression are explored. Experimental results on CMU PIE, the FERET, and the Multi-PIE face databases show that the proposed bias-variance tradeoff can achieve considerable reinforcement in recognition performance.

  3. Trajectory Planning with Pose Feedback for a Dual-Arm Space Robot

    Directory of Open Access Journals (Sweden)

    Yicheng Liu

    2016-01-01

    Full Text Available In order to obtain high precision path tracking for a dual-arm space robot, a trajectory planning method with pose feedback is proposed to be introduced into the design process in this paper. Firstly, pose error kinematic models are derived from the related kinematics and desired pose command for the end-effector and the base, respectively. On this basis, trajectory planning with pose feedback is proposed from a control perspective. Theoretical analyses show that the proposed trajectory planning algorithm can guarantee that pose error converges to zero exponentially for both the end-effector and the base when the robot is out of singular configuration. Compared with the existing algorithms, the proposed algorithm can lead to higher precision path tracking for the end-effector. Furthermore, the algorithm renders the system good anti-interference property for the base. Simulation results demonstrate the effectiveness of the proposed trajectory planning algorithm.

  4. A Support System for the Electric Appliance Control Using Pose Recognition

    Science.gov (United States)

    Kawano, Takuya; Yamamoto, Kazuhiko; Kato, Kunihito; Hongo, Hitoshi

    In this paper, we propose an electric appliance control support system for aged and bedridden people using pose recognition. We proposed a pose recognition system that distinguishes between seven poses of the user on the bed. First, the face and arm regions of the user are detected by using the skin color. Our system focuses a recognition region surrounding the face region. Next, the higher order local autocorrelation features within the region are extracted. The linear discriminant analysis creates the coefficient matrix that can optimally distinguish among training data from the seven poses. Our algorithm can recognize the seven poses even if the subject wears different clothes and slightly shifts or slants on the bed. From the experimental results, our system achieved an accuracy rate of over 99 %. Then, we show that it possibles to construct one of a user-friendly system.

  5. Head Pose Estimation Using Multilinear Subspace Analysis for Robot Human Awareness

    Science.gov (United States)

    Ivanov, Tonislav; Matthies, Larry; Vasilescu, M. Alex O.

    2009-01-01

    Mobile robots, operating in unconstrained indoor and outdoor environments, would benefit in many ways from perception of the human awareness around them. Knowledge of people's head pose and gaze directions would enable the robot to deduce which people are aware of the its presence, and to predict future motions of the people for better path planning. To make such inferences, requires estimating head pose on facial images that are combination of multiple varying factors, such as identity, appearance, head pose, and illumination. By applying multilinear algebra, the algebra of higher-order tensors, we can separate these factors and estimate head pose regardless of subject's identity or image conditions. Furthermore, we can automatically handle uncertainty in the size of the face and its location. We demonstrate a pipeline of on-the-move detection of pedestrians with a robot stereo vision system, segmentation of the head, and head pose estimation in cluttered urban street scenes.

  6. Application of Shape Similarity in Pose Selection and Virtual Screening in CSARdock2014 Exercise.

    Science.gov (United States)

    Kumar, Ashutosh; Zhang, Kam Y J

    2016-06-27

    To evaluate the applicability of shape similarity in docking-based pose selection and virtual screening, we participated in the CSARdock2014 benchmark exercise for identifying the correct docking pose of inhibitors targeting factor XA, spleen tyrosine kinase, and tRNA methyltransferase. This exercise provides a valuable opportunity for researchers to test their docking programs, methods, and protocols in a blind testing environment. In the CSARdock2014 benchmark exercise, we have implemented an approach that uses ligand 3D shape similarity to facilitate docking-based pose selection and virtual screening. We showed here that ligand 3D shape similarity between bound poses could be used to identify the native-like pose from an ensemble of docking-generated poses. Our method correctly identified the native pose as the top-ranking pose for 73% of test cases in a blind testing environment. Moreover, the pose selection results also revealed an excellent correlation between ligand 3D shape similarity scores and RMSD to X-ray crystal structure ligand. In the virtual screening exercise, the average RMSD for our pose prediction was found to be 1.02 Å, and it was one of the top performances achieved in CSARdock2014 benchmark exercise. Furthermore, the inclusion of shape similarity improved virtual screening performance of docking-based scoring and ranking. The coefficient of determination (r(2)) between experimental activities and docking scores for 276 spleen tyrosine kinase inhibitors was found to be 0.365 but reached 0.614 when the ligand 3D shape similarity was included.

  7. Status of Muslim Immigrants' Children with Learning Difficulties in Vienna

    Science.gov (United States)

    Mohsin, M. Naeem; Shabbir, Muhammad; Saeed, Wizra; Mohsin, M. Saleem

    2013-01-01

    The study was conducted to know the status of Muslim immigrants' children with learning difficulties and importance of parents' involvement for the education whose children are with learning difficulties, and the factors responsible for the learning difficulties among immigrants' children. There were 81 immigrant children with learning…

  8. FAMILY BUSINESSES AND THE DIFFICULTIES ENCOUNTERED BY

    Directory of Open Access Journals (Sweden)

    Alessandra Martins

    2009-05-01

    Full Text Available There are few family owned businesses that survive to the next generation. In general, 30% of these businesses are passed on to second generation families and less than 15% survive to third generation families. There has been little research done on third generation family businesses. Therefore the main purpose of this paper is to identify the principal difficulties of passing on managerial skills to the third generation owners. This study uses a case study of a Brazilian family organization composed of twelve enterprises. The instrument to collect data was an individually guided recorded interview with all of the family managers (1ª, 2ª e 3ª generation. The technique applied, was suggested for Miles & Huberman (1994 to group the data in analytical categories to facilitate the analyzed speeches contained in the 49 blocks of responses. As a result, the transition the business to the third generation owners has been strongly associated with the relation between family and business by the following factors: a the succession process influenced by emotional and family values; b conflicts, rivalries and divergences of strategic visions and business goals between the family generations; c lack of professional criteria to hire relatives; and d fragility of communication and consequent asymmetry of information among the family members.

  9. Respiratory difficulties and breathing disorders in achondroplasia.

    Science.gov (United States)

    Afsharpaiman, S; Saburi, A; Waters, Karen A

    2013-12-01

    Respiratory difficulties and breathing disorders in achondroplasia are thought to underlie the increased risk for sudden infant death and neuropsychological deficits seen in this condition. This review evaluates literature regarding respiratory dysfunctions and their sequelae in patients with achondroplasia. The limited number of prospective studies of respiratory disease in achondroplasia means that observational studies and case series provide a large proportion of the data regarding the spectrum of respiratory diseases in achondroplasia and their treatments. Amongst clinical respiratory problems described, snoring is the commonest observed abnormality, but the reported incidence of obstructive sleep apnoea (OSA) shows wide variance (10% to 75%). Reported treatments of OSA include adenotonsillectomy, the use of CPAP, and surgical improvement of the airway, including mid-face advancement. Otolaryngologic manifestations are also common. Respiratory failure due to small thoracic volumes is reported, but uncommon. Mortality rate at all ages was 2.27 (CI: 1.7-3.0) with age-specific mortality increased at all ages. Sudden death was most common in infants and children. Cardiovascular events are the main cause of mortality in adults. Despite earlier recognition and treatment of respiratory complications of achondroplasia, increased mortality rates and other complications remain high. Future and ongoing evaluation of the prevalence and impact of respiratory disorders, particularly OSA, in achondroplasia is recommended. Crown Copyright © 2013. Published by Elsevier Ltd. All rights reserved.

  10. Fractions Learning in Children With Mathematics Difficulties.

    Science.gov (United States)

    Tian, Jing; Siegler, Robert S

    Learning fractions is difficult for children in general and especially difficult for children with mathematics difficulties (MD). Recent research on developmental and individual differences in fraction knowledge of children with MD and typically achieving (TA) children has demonstrated that U.S. children with MD start middle school behind their TA peers in fraction understanding and fall further behind during middle school. In contrast, Chinese children, who like the MD children in the United States score in the bottom one third of the distribution in their country, possess reasonably good fraction understanding. We interpret these findings within the framework of the integrated theory of numerical development. By emphasizing the importance of fraction magnitude knowledge for numerical understanding in general, the theory proved useful for understanding differences in fraction knowledge between MD and TA children and for understanding how knowledge can be improved. Several interventions demonstrated the possibility of improving fraction magnitude knowledge and producing benefits that generalize to fraction arithmetic learning among children with MD. The reasonably good fraction understanding of Chinese children with MD and several successful interventions with U.S. students provide hope for the improvement of fraction knowledge among American children with MD.

  11. Multidisciplinary intervention for childhood feeding difficulties.

    Science.gov (United States)

    Marshall, Jeanne; Hill, Rebecca J; Ware, Robert S; Ziviani, Jenny; Dodrill, Pamela

    2015-05-01

    The aim of the study was to determine whether operant conditioning (OC) or systematic desensitization (SysD) intervention resulted in more improvements in dietary variety/intake, and more reductions in difficult mealtime behaviors. Children 2 to 6 years with autism spectrum disorder or with a nonmedically complex history were recruited. Feeding difficulties were confirmed based on clinical assessment. Participants were randomized to receive 10 OC or SysD sessions (parents could opt for intervention once per week, or intensively within a week). Immersive parent education was delivered across both arms. A 3-month review was provided to measure outcomes postintervention. In total, 68 participants (87%) completed the study. There were no significant differences in outcome measures between the OC and SysD intervention groups from baseline to 3-month review. When the data were combined across both groups, however, significant improvements in primary outcome measures were observed (P education, these 2 intervention approaches are effective. Further research is required in exploring these interventions across other subgroups, and examining outcomes for longer periods.

  12. [Difficulties in psychology and sexual behavior].

    Science.gov (United States)

    1973-01-01

    After an introduction by S. Kepes (Fertilite Orthogenie 4(4): 174-177,1972) the participants and audience discussed general topics such as the physician-patient relationship, unconscious motives, attitudes of male partners and physicians, and treatment of minors. Resistance by male partners toward contraception was considered due to fear of inadequacy in the face of female sexuality or to adherence to a double moral standard for wives. A gynecologist claimed that high school students are more likely to request contraception and use it effectively than they were 5 years ago; a midwife said that less privileged adolescents frequently become pregnant. Opinions were expressed that it is inappropriate to consider contraception from a psychological viewpoint, since it is part of a revolution toward a better life; that some psychological difficulties come from the doctor having preferences for certain methods; that the pill does not cause frigidity but is often blamed for preexisting problems; that the press frightens women away from taking the pill; that physicians should prescribe contraception to minors without seeking parental consent (unlawful in France).

  13. [Increasing difficulties for scientific publication in Venezuela].

    Science.gov (United States)

    Ryder, Elena

    2014-03-01

    A very important increase in the costs of the edition of scientific journals has taken place in Venezuela, due to difficulties in obtaining imported free acid paper and other materials used for handling documents. Like other journals, Investigaci6n Clinica has been considering switching completely to a digital publication format; however there are several reasons that prevent us to doing it at this time: the journal is distributed in printed form to many national institutions, which do not have immediate access to digital information. In addition, there exists a commitment of shipment of printed issues for some international indices and in exchange with other national and foreign journals, whose printed format we receive. Another important aspect is that our University maintains a weak technological platform that makes difficult the immediacy required for the interchange with authors and consulted referees of received papers; and there is a latent danger of limitations in the use of digital technologies, due to current national politic problems. Consequently, we need to continue with the printed format, but must reduce the amount of printed issues, so as not to limit the number of papers published in each edition. Nevertheless, there is an ever increasing number of contributions from foreign researches and Investigaci6n Clinica has been recently included in two new international indices, the SEIIC from Argentina and the Infobase Index from India, reasons that obligate us to maintain our levels of excellence and commitment to our authors and readers.

  14. Assessing exposure risks for aquatic organisms posed by Tamiflu use under seasonal influenza and pandemic conditions

    International Nuclear Information System (INIS)

    Chen, Wei-Yu; Lin, Chia-Jung; Liao, Chung-Min

    2014-01-01

    Environmental pollution by anti-influenza drugs is increasingly recognized as a threat to aquatic environments. However, little is known about empirical data on risk effects posed by environmentally relevant concentrations of anti-influenza drug based on recently published ecotoxicological researches in Taiwan. Here we linked ecotoxicology models with an epidemiological scheme to assess exposure risks of aquatic organisms and environmental hazards posed by antiviral oseltamivir (Tamiflu) use in Taiwan. Built on published bioassays, we used probabilistic risk assessment model to estimate potential threats of environmentally relevant hazards on algae, daphnid, and zerbrafish. We found that Tamiflu use was unlikely to pose a significant chronic environmental risk to daphnia and zebrafish during seasonal influenza. However, the chronic environmental risk posed by Tamiflu use during pandemic was alarming. We conclude that no significant risk to algal growth was found during seasonal influenza and high pandemic Tamiflu use. -- Highlights: • Environmentally relevant concentrations of anti-influenza drug have ecotoxicologically important effects. • Tamiflu is unlikely to pose a significant chronic environmental risk during seasonal influenza. • Chronic environmental risk posed by Tamiflu during pandemic is alarming. • Tertiary process in sewage treatment plants is crucial in mitigating Tamiflu exposure risk. -- A probabilistic framework can be used for assessing exposure risks posed by environmentally relevant concentrations of anti-influenza drug in aquatic ecosystems

  15. Attribute And-Or Grammar for Joint Parsing of Human Pose, Parts and Attributes.

    Science.gov (United States)

    Park, Seyoung; Nie, Xiaohan; Zhu, Song-Chun

    2017-07-25

    This paper presents an attribute and-or grammar (A-AOG) model for jointly inferring human body pose and human attributes in a parse graph with attributes augmented to nodes in the hierarchical representation. In contrast to other popular methods in the current literature that train separate classifiers for poses and individual attributes, our method explicitly represents the decomposition and articulation of body parts, and account for the correlations between poses and attributes. The A-AOG model is an amalgamation of three traditional grammar formulations: (i)Phrase structure grammar representing the hierarchical decomposition of the human body from whole to parts; (ii)Dependency grammar modeling the geometric articulation by a kinematic graph of the body pose; and (iii)Attribute grammar accounting for the compatibility relations between different parts in the hierarchy so that their appearances follow a consistent style. The parse graph outputs human detection, pose estimation, and attribute prediction simultaneously, which are intuitive and interpretable. We conduct experiments on two tasks on two datasets, and experimental results demonstrate the advantage of joint modeling in comparison with computing poses and attributes independently. Furthermore, our model obtains better performance over existing methods for both pose estimation and attribute prediction tasks.

  16. Coupled multiview autoencoders with locality sensitivity for three-dimensional human pose estimation

    Science.gov (United States)

    Yu, Jialin; Sun, Jifeng; Luo, Shasha; Duan, Bichao

    2017-09-01

    Estimating three-dimensional (3D) human poses from a single camera is usually implemented by searching pose candidates with image descriptors. Existing methods usually suppose that the mapping from feature space to pose space is linear, but in fact, their mapping relationship is highly nonlinear, which heavily degrades the performance of 3D pose estimation. We propose a method to recover 3D pose from a silhouette image. It is based on the multiview feature embedding (MFE) and the locality-sensitive autoencoders (LSAEs). On the one hand, we first depict the manifold regularized sparse low-rank approximation for MFE and then the input image is characterized by a fused feature descriptor. On the other hand, both the fused feature and its corresponding 3D pose are separately encoded by LSAEs. A two-layer back-propagation neural network is trained by parameter fine-tuning and then used to map the encoded 2D features to encoded 3D poses. Our LSAE ensures a good preservation of the local topology of data points. Experimental results demonstrate the effectiveness of our proposed method.

  17. Monocular-Based 6-Degree of Freedom Pose Estimation Technology for Robotic Intelligent Grasping Systems

    Directory of Open Access Journals (Sweden)

    Tao Liu

    2017-02-01

    Full Text Available Industrial robots are expected to undertake ever more advanced tasks in the modern manufacturing industry, such as intelligent grasping, in which robots should be capable of recognizing the position and orientation of a part before grasping it. In this paper, a monocular-based 6-degree of freedom (DOF pose estimation technology to enable robots to grasp large-size parts at informal poses is proposed. A camera was mounted on the robot end-flange and oriented to measure several featured points on the part before the robot moved to grasp it. In order to estimate the part pose, a nonlinear optimization model based on the camera object space collinearity error in different poses is established, and the initial iteration value is estimated with the differential transformation. Measuring poses of the camera are optimized based on uncertainty analysis. Also, the principle of the robotic intelligent grasping system was developed, with which the robot could adjust its pose to grasp the part. In experimental tests, the part poses estimated with the method described in this paper were compared with those produced by a laser tracker, and results show the RMS angle and position error are about 0.0228° and 0.4603 mm. Robotic intelligent grasping tests were also successfully performed in the experiments.

  18. Pose Estimation and Adaptive Robot Behaviour for Human-Robot Interaction

    DEFF Research Database (Denmark)

    Svenstrup, Mikael; Hansen, Søren Tranberg; Andersen, Hans Jørgen

    2009-01-01

    Abstract—This paper introduces a new method to determine a person’s pose based on laser range measurements. Such estimates are typically a prerequisite for any human-aware robot navigation, which is the basis for effective and timeextended interaction between a mobile robot and a human. The robot......’s pose. The resulting pose estimates are used to identify humans who wish to be approached and interacted with. The interaction motion of the robot is based on adaptive potential functions centered around the person that respect the persons social spaces. The method is tested in experiments...

  19. Head Pose Estimation on Eyeglasses Using Line Detection and Classification Approach

    Science.gov (United States)

    Setthawong, Pisal; Vannija, Vajirasak

    This paper proposes a unique approach for head pose estimation of subjects with eyeglasses by using a combination of line detection and classification approaches. Head pose estimation is considered as an important non-verbal form of communication and could also be used in the area of Human-Computer Interface. A major improvement of the proposed approach is that it allows estimation of head poses at a high yaw/pitch angle when compared with existing geometric approaches, does not require expensive data preparation and training, and is generally fast when compared with other approaches.

  20. Measurement of functional task difficulty during motor learning: What level of difficulty corresponds to the optimal challenge point?

    Science.gov (United States)

    Akizuki, Kazunori; Ohashi, Yukari

    2015-10-01

    The relationship between task difficulty and learning benefit was examined, as was the measurability of task difficulty. Participants were required to learn a postural control task on an unstable surface at one of four different task difficulty levels. Results from the retention test showed an inverted-U relationship between task difficulty during acquisition and motor learning. The second-highest level of task difficulty was the most effective for motor learning, while learning was delayed at the most and least difficult levels. Additionally, the results indicate that salivary α-amylase and the performance dimension of the National Aeronautics and Space Administration-Task Load Index (NASA-TLX) are useful indices of task difficulty. Our findings suggested that instructors may be able to adjust task difficulty based on salivary α-amylase and the performance dimension of the NASA-TLX to enhance learning. Copyright © 2015 Elsevier B.V. All rights reserved.

  1. Trotting Gait of a Quadruped Robot Based on the Time-Pose Control Method

    Directory of Open Access Journals (Sweden)

    Cai RunBin

    2013-02-01

    Full Text Available We present the Time-Pose control method for the trotting gait of a quadruped robot on flat ground and up a slope. The method, with brief control structure, real-time operation ability and high adaptability, divides quadruped robot control into gait control and pose control. Virtual leg and intuitive controllers are introduced to simplify the model and generate the trajectory of mass centre and location of supporting legs in gait control, while redundancy optimization is used for solving the inverse kinematics in pose control. The models both on flat ground and up a slope are fully analysed, and different kinds of optimization methods are compared using the manipulability measure in order to select the best option. Simulations are performed, which prove that the Time-Pose control method is realizable for these two kinds of environment.

  2. Risks posed by large seismic events in the gold mining districts of South Africa

    CSIR Research Space (South Africa)

    Durrheim, RJ

    2011-01-01

    Full Text Available buildings are considered vulnerable to damage by large seismic events, posing safety and financial risks. It is recommended that an earthquake engineer inspect the building stock and review the content and enforcement of building codes. Appropriate training...

  3. A Grasp-Pose Generation Method Based on Gaussian Mixture Models

    Directory of Open Access Journals (Sweden)

    Wenjia Wu

    2015-11-01

    Full Text Available A Gaussian Mixture Model (GMM-based grasp-pose generation method is proposed in this paper. Through offline training, the GMM is set up and used to depict the distribution of the robot's reachable orientations. By dividing the robot's workspace into small 3D voxels and training the GMM for each voxel, a look-up table covering all the workspace is built with the x, y and z positions as the index and the GMM as the entry. Through the definition of Task Space Regions (TSR, an object's feasible grasp poses are expressed as a continuous region. With the GMM, grasp poses can be preferentially sampled from regions with high reachability probabilities in the online grasp-planning stage. The GMM can also be used as a preliminary judgement of a grasp pose's reachability. Experiments on both a simulated and a real robot show the superiority of our method over the existing method.

  4. Improved pose and affinity predictions using different protocols tailored on the basis of data availability

    Science.gov (United States)

    Prathipati, Philip; Nagao, Chioko; Ahmad, Shandar; Mizuguchi, Kenji

    2016-09-01

    The D3R 2015 grand drug design challenge provided a set of blinded challenges for evaluating the applicability of our protocols for pose and affinity prediction. In the present study, we report the application of two different strategies for the two D3R protein targets HSP90 and MAP4K4. HSP90 is a well-studied target system with numerous co-crystal structures and SAR data. Furthermore the D3R HSP90 test compounds showed high structural similarity to existing HSP90 inhibitors in BindingDB. Thus, we adopted an integrated docking and scoring approach involving a combination of both pharmacophoric and heavy atom similarity alignments, local minimization and quantitative structure activity relationships modeling, resulting in the reasonable prediction of pose [with the root mean square deviation (RMSD) values of 1.75 Å for mean pose 1, 1.417 Å for the mean best pose and 1.85 Å for the mean all poses] and affinity (ROC AUC = 0.702 at 7.5 pIC50 cut-off and R = 0.45 for 180 compounds). The second protein, MAP4K4, represents a novel system with limited SAR and co-crystal structure data and little structural similarity of the D3R MAP4K4 test compounds to known MAP4K4 ligands. For this system, we implemented an exhaustive pose and affinity prediction protocol involving docking and scoring using the PLANTS software which considers side chain flexibility together with protein-ligand fingerprints analysis assisting in pose prioritization. This protocol through fares poorly in pose prediction (with the RMSD values of 4.346 Å for mean pose 1, 4.69 Å for mean best pose and 4.75 Å for mean all poses) and produced reasonable affinity prediction (AUC = 0.728 at 7.5 pIC50 cut-off and R = 0.67 for 18 compounds, ranked 1st among 80 submissions).

  5. Web-based Visualisation of Head Pose and Facial Expressions Changes:

    DEFF Research Database (Denmark)

    Kalliatakis, Grigorios; Vidakis, Nikolaos; Triantafyllidis, Georgios

    2016-01-01

    Despite significant recent advances in the field of head pose estimation and facial expression recognition, raising the cognitive level when analysing human activity presents serious challenges to current concepts. Motivated by the need of generating comprehensible visual representations from...... and accurately estimate head pose changes in unconstrained environment. In order to complete the secondary process of recognising four universal dominant facial expressions (happiness, anger, sadness and surprise), emotion recognition via facial expressions (ERFE) was adopted. After that, a lightweight data...

  6. Consistently Showing Your Best Side? Intra-individual Consistency in #Selfie Pose Orientation

    Science.gov (United States)

    Lindell, Annukka K.

    2017-01-01

    Painted and photographic portraits of others show an asymmetric bias: people favor their left cheek. Both experimental and database studies confirm that the left cheek bias extends to selfies. To date all such selfie studies have been cross-sectional; whether individual selfie-takers tend to consistently favor the same pose orientation, or switch between multiple poses, remains to be determined. The present study thus examined intra-individual consistency in selfie pose orientations. Two hundred selfie-taking participants (100 male and 100 female) were identified by searching #selfie on Instagram. The most recent 10 single-subject selfies for the each of the participants were selected and coded for type of selfie (normal; mirror) and pose orientation (left, midline, right), resulting in a sample of 2000 selfies. Results indicated that selfie-takers do tend to consistently adopt a preferred pose orientation (α = 0.72), with more participants showing an overall left cheek bias (41%) than would be expected by chance (overall right cheek bias = 31.5%; overall midline bias = 19.5%; no overall bias = 8%). Logistic regression modellng, controlling for the repeated measure of participant identity, indicated that sex did not affect pose orientation. However, selfie type proved a significant predictor when comparing left and right cheek poses, with a stronger left cheek bias for mirror than normal selfies. Overall, these novel findings indicate that selfie-takers show intra-individual consistency in pose orientation, and in addition, replicate the previously reported left cheek bias for selfies and other types of portrait, confirming that the left cheek bias also presents within individuals’ selfie corpora. PMID:28270790

  7. A review of cooperative and uncooperative spacecraft pose determination techniques for close-proximity operations

    Science.gov (United States)

    Opromolla, Roberto; Fasano, Giancarmine; Rufino, Giancarlo; Grassi, Michele

    2017-08-01

    The capability of an active spacecraft to accurately estimate its relative position and attitude (pose) with respect to an active/inactive, artificial/natural space object (target) orbiting in close-proximity is required to carry out various activities like formation flying, on-orbit servicing, active debris removal, and space exploration. According to the specific mission scenario, the pose determination task involves both theoretical and technological challenges related to the search for the most suitable algorithmic solution and sensor architecture, respectively. As regards the latter aspect, electro-optical sensors represent the best option as their use is compatible with mass and power limitation of micro and small satellites, and their measurements can be processed to estimate all the pose parameters. Overall, the degree of complexity of the challenges related to pose determination largely varies depending on the nature of the targets, which may be actively/passively cooperative, uncooperative but known, or uncooperative and unknown space objects. In this respect, while cooperative pose determination has been successfully demonstrated in orbit, the uncooperative case is still under study by universities, research centers, space agencies and private companies. However, in both the cases, the demand for space applications involving relative navigation maneuvers, also in close-proximity, for which pose determination capabilities are mandatory, is significantly increasing. In this framework, a review of state-of-the-art techniques and algorithms developed in the last decades for cooperative and uncooperative pose determination by processing data provided by electro-optical sensors is herein presented. Specifically, their main advantages and drawbacks in terms of achieved performance, computational complexity, and sensitivity to variability of pose and target geometry, are highlighted.

  8. The Economic Impact of Terrorism in the Near East: Understanding the Threats Posed by Militant Groups

    Science.gov (United States)

    2015-05-21

    terrorist attacks of September 11th, 2001 researchers have sought to better understand the macroeconomic consequences of terrorism. Despite a...The Economic Impact of Terrorism in the Near East: Understanding the Threats Posed by Militant Groups A Monograph by MAJ Joshua Glonek...SUBTITLE The Economic Impact of Terrorism in the Near East: Understanding the Threats Posed by Militant Groups 5a. CONTRACT NUMBER 5b. GRANT

  9. Pose Estimation with a Kinect for Ergonomic Studies: Evaluation of the Accuracy Using a Virtual Mannequin

    Directory of Open Access Journals (Sweden)

    Pierre Plantard

    2015-01-01

    Full Text Available Analyzing human poses with a Kinect is a promising method to evaluate potentials risks of musculoskeletal disorders at workstations. In ecological situations, complex 3D poses and constraints imposed by the environment make it difficult to obtain reliable kinematic information. Thus, being able to predict the potential accuracy of the measurement for such complex 3D poses and sensor placements is challenging in classical experimental setups. To tackle this problem, we propose a new evaluation method based on a virtual mannequin. In this study, we apply this method to the evaluation of joint positions (shoulder, elbow, and wrist, joint angles (shoulder and elbow, and the corresponding RULA (a popular ergonomics assessment grid upper-limb score for a large set of poses and sensor placements. Thanks to this evaluation method, more than 500,000 configurations have been automatically tested, which would be almost impossible to evaluate with classical protocols. The results show that the kinematic information obtained by the Kinect software is generally accurate enough to fill in ergonomic assessment grids. However inaccuracy strongly increases for some specific poses and sensor positions. Using this evaluation method enabled us to report configurations that could lead to these high inaccuracies. As a supplementary material, we provide a software tool to help designers to evaluate the expected accuracy of this sensor for a set of upper-limb configurations. Results obtained with the virtual mannequin are in accordance with those obtained from a real subject for a limited set of poses and sensor placements.

  10. Muscle utilization patterns vary by skill levels of the practitioners across specific yoga poses (asanas).

    Science.gov (United States)

    Ni, Meng; Mooney, Kiersten; Balachandran, Anoop; Richards, Luca; Harriell, Kysha; Signorile, Joseph F

    2014-08-01

    To compare muscle activation patterns in 14 dominant side muscles during different yoga poses across three skill levels. Mixed repeated-measures descriptive study. University neuromuscular research laboratory, Miami, US. A group of 36 yoga practitioners (9 M/27 F; mean ± SD, 31.6 ± 12.6 years) with at least 3 months yoga practice experience. Each of the 11 surya namaskar poses A and B was performed separately for 15s and the surface electromyography for 14 muscles were recorded. Normalized root mean square of the electromyographic signal (NrmsEMG) for 14 muscles (5 upper body, 4 trunk, 5 lower body). There were significant main effects of pose for all fourteen muscles except middle trapezius (p<.02) and of skill level for the vastus medialis; p=.027). A significant skill level × pose interaction existed for five muscles (pectoralis major sternal head, anterior deltoid, medial deltoid, upper rectus abdominis and gastrocnemius lateralis; p<.05). Post hoc analyses using Bonferroni comparisons indicated that different poses activated specific muscle groups; however, this varied by skill level. Our results indicate that different poses can produce specific muscle activation patterns which may vary due to practitioners' skill levels. This information can be used in designing rehabilitation and training programs and for cuing during yoga training. Copyright © 2014 Elsevier Ltd. All rights reserved.

  11. Multi-Task Convolutional Neural Network for Pose-Invariant Face Recognition

    Science.gov (United States)

    Yin, Xi; Liu, Xiaoming

    2018-02-01

    This paper explores multi-task learning (MTL) for face recognition. We answer the questions of how and why MTL can improve the face recognition performance. First, we propose a multi-task Convolutional Neural Network (CNN) for face recognition where identity classification is the main task and pose, illumination, and expression estimations are the side tasks. Second, we develop a dynamic-weighting scheme to automatically assign the loss weight to each side task, which is a crucial problem in MTL. Third, we propose a pose-directed multi-task CNN by grouping different poses to learn pose-specific identity features, simultaneously across all poses. Last but not least, we propose an energy-based weight analysis method to explore how CNN-based MTL works. We observe that the side tasks serve as regularizations to disentangle the variations from the learnt identity features. Extensive experiments on the entire Multi-PIE dataset demonstrate the effectiveness of the proposed approach. To the best of our knowledge, this is the first work using all data in Multi-PIE for face recognition. Our approach is also applicable to in-the-wild datasets for pose-invariant face recognition and achieves comparable or better performance than state of the art on LFW, CFP, and IJB-A datasets.

  12. Creating a supportive learning environment for students with learning difficulties

    OpenAIRE

    Grah, Jana

    2013-01-01

    Co-building of supporting learning environment for the learners with learning difficulties is one of the 21st century inclusive school’s elements. Since the physical presence of learners with learning difficulties in the classroom does not self-evidently lead to an effective co-operation and implementation of 21st century inclusive school, I have dedicated my doctor thesis to the establishment of supporting learning environment for the learners with learning difficulties in primary school wit...

  13. Prediction and Stability of Mathematics Skill and Difficulty

    OpenAIRE

    Martin, Rebecca B.; Cirino, Paul T.; Barnes, Marcia A.; Ewing-Cobbs, Linda; Fuchs, Lynn S.; Stuebing, Karla K.; Fletcher, Jack M.

    2012-01-01

    The present study evaluated the stability of math learning difficulties over a 2-year period and investigated several factors that might influence this stability (categorical vs. continuous change, liberal vs. conservative cut point, broad vs. specific math assessment); the prediction of math performance over time and by performance level was also evaluated. Participants were 144 students initially identified as having a math difficulty (MD) or no learning difficulty according to low achievem...

  14. Difficulties in emotion regulation in patients with eating disorders.

    Science.gov (United States)

    Ruscitti, Catherine; Rufino, Katrina; Goodwin, Natalie; Wagner, Rebecca

    2016-01-01

    A defining characteristic of eating disorders (EDs) is difficulty with emotion regulation (ER). Previous research indicates that ED subtypes demonstrate differing ER difficulties. Specifically, individuals with Anorexia Nervosa (AN) or Bulimia Nervosa (BN) show greater impairment in their ability to regulate emotions in areas such as achieving goals while upset, reacting impulsively to distress, and effectively using coping strategies, as compared to those with Binge Eating Disorder (BED). However, limited research includes the diagnostic category of Eating Disorder, Not Otherwise Specified (EDNOS). The aim of this study was to better understand ER difficulties for all ED diagnoses, especially EDNOS. It was hypothesized that patients with EDs will demonstrate similar ER difficulties as psychiatric patients without EDs and that patients with EDNOS will be similar in their total level of ER difficulties but will differ in their specific types of difficulties in ER as compared to patients with other EDs. Participants included 404 adults presenting to an inpatient psychiatric hospital. Psychiatric diagnoses, including EDs, were determined using the Structured Clinical Interview for DSM Disorders. Differences in specific and overall difficulties with ER were examined across psychiatric patients using the multidimensional Difficulties in Emotion Regulation Scale. Results of this study indicate that individuals with EDs have greater ER difficulties in most domains of ER and that those with BED and EDNOS demonstrate the most significant differences in ER as compared to psychiatric patients without EDs. Additionally, it was found that ED subtypes typically did not differ in terms of specific difficulties in ER. One exception emerged indicating that individuals with BED demonstrated significantly greater difficulty on the Limited Access to Emotion Regulation Strategies subscale as compared to those with EDNOS. Researchers were able to clarify difficulties in ER across ED

  15. Grammatical Templates: Improving Text Difficulty Evaluation for Language Learners

    OpenAIRE

    Wang, Shuhan; Andersen, Erik

    2016-01-01

    Language students are most engaged while reading texts at an appropriate difficulty level. However, existing methods of evaluating text difficulty focus mainly on vocabulary and do not prioritize grammatical features, hence they do not work well for language learners with limited knowledge of grammar. In this paper, we introduce grammatical templates, the expert-identified units of grammar that students learn from class, as an important feature of text difficulty evaluation. Experimental clas...

  16. Late Emerging Reading Difficulties in English Language Learners

    OpenAIRE

    Garcia, Nicole Marie

    2015-01-01

    Research has identified a group of students who do not begin to exhibit reading difficulties until fourth or fifth grade, suggesting late-emerging reading difficulties. Considering that these students do not show signs of reading difficulties in early grades, attempting to identify these students early becomes problematic. Additionally, little is known regarding the characteristics of late-emerging reading deficits within English language learner (ELL) populations. The purpose of this study w...

  17. The Effect of Problem Solving and Problem Posing Models and Innate Ability to Students Achievement

    Directory of Open Access Journals (Sweden)

    Ratna Kartika Irawati

    2015-04-01

    Full Text Available Pengaruh Model Problem Solving dan Problem Posing serta Kemampuan Awal terhadap Hasil Belajar Siswa   Abstract: Chemistry concepts understanding features abstract quality and requires higher order thinking skills. Yet, the learning on chemistry has not boost the higher order thinking skills of the students. The use of the learning model of Problem Solving and Problem Posing in observing the innate ability of the student is expected to resolve the issue. This study aims to determine the learning model which is effective to improve the study of the student with different level of innate ability. This study used the quasi-experimental design. The research data used in this research is the quiz/test of the class which consist of 14 multiple choice questions and 5 essay questions. The data analysis used is ANOVA Two Ways. The results showed that Problem Posing is more effective to improve the student compared to Problem Solving, students with high level of innate ability have better outcomes in learning rather than the students with low level of innate ability after being applied with the Problem solving and Problem posing model, further, Problem Solving and Problem Posing is more suitable to be applied to the students with high level of innate ability. Key Words: problem solving, problem posing, higher order thinking skills, innate ability, learning outcomes   Abstrak: Pemahaman konsep-konsep kimia yang bersifat abstrak membutuhkan keterampilan berpikir tingkat tinggi. Pembelajaran kimia belum mendorong siswa melakukan keterampilan berpikir tingkat tinggi. Penggunaan model pembelajaran Problem Solving dan Problem Posing dengan memperhatikan kemampuan awal siswa diduga dapat mengatasi masalah tersebut. Penelitian ini bertujuan untuk mengetahui model pembelajaran yang efektif dalam meningkatkan hasil belajar dengan kemampuan awal siswa yang berbeda. Penelitian ini menggunakan rancangan eksperimen semu. Data penelitian menggunakan tes hasil belajar

  18. Pose measurement method with six parameters for microassembly based on an optical micrometer

    Science.gov (United States)

    Ye, Xin; Wang, Qiang; Zhang, Zhi-jing; Sun, Yuan; Zhang, Xiao-feng

    2009-07-01

    This paper presents a new pose measurement method of microminiature parts that is capable of transforming one dimension (1D) contour size obtained by optical micrometer to three dimension (3D) data with six parameters for microassembly. Pose measurement is one of the most important processes for microminiature parts' alignment and insertion in microassembly. During the past few years, researchers have developed their microassembly systems focusing on visual identification to obtain two or three dimension data with no more than three parameters. Scanning electronic microscope (SEM), optical microscope, and stereomicroscope are applied in their systems. However, as structures of microminiature parts become increasingly complex, six parameters to represent their position and orientation are specifically needed. Firstly, The pose measurement model is established based on the introduction of measuring objects and measuring principle of optical micrometer. The measuring objects are microminiature parts with complex 3D structure. Two groups of two dimension (2D) data are gathered at two different measurement positions. Then part pose with 6 parameters is calculated, including 3 position parameters of feature point of the part and 3 orientation parameters of the part axis. Secondly, pose measurement process for a small shaft, vertical orientation determination, and position parameters obtaining are presented. 2D data is gathered by scanning the generatrix of the part, and valid data is extracted and saved in arrays. A vertical orientation criterion is proposed to determine whether the part is parallel to the Z-axis of the coordinate. If not, 2D data will be fixed into a linear equation using least square algorithm. Then orientation parameters are calculated. Center of Part End (CPE) is selected as feature point of the part, and its position parameters are extracted form two group of 2D data. Finally, a fast pose measurement device is developed and representative

  19. Generalized Hough transform based time invariant action recognition with 3D pose information

    Science.gov (United States)

    Muench, David; Huebner, Wolfgang; Arens, Michael

    2014-10-01

    Human action recognition has emerged as an important field in the computer vision community due to its large number of applications such as automatic video surveillance, content based video-search and human robot interaction. In order to cope with the challenges that this large variety of applications present, recent research has focused more on developing classifiers able to detect several actions in more natural and unconstrained video sequences. The invariance discrimination tradeoff in action recognition has been addressed by utilizing a Generalized Hough Transform. As a basis for action representation we transform 3D poses into a robust feature space, referred to as pose descriptors. For each action class a one-dimensional temporal voting space is constructed. Votes are generated from associating pose descriptors with their position in time relative to the end of an action sequence. Training data consists of manually segmented action sequences. In the detection phase valid human 3D poses are assumed as input, e.g. originating from 3D sensors or monocular pose reconstruction methods. The human 3D poses are normalized to gain view-independence and transformed into (i) relative limb-angle space to ensure independence of non-adjacent joints or (ii) geometric features. In (i) an action descriptor consists of the relative angles between limbs and their temporal derivatives. In (ii) the action descriptor consists of different geometric features. In order to circumvent the problem of time-warping we propose to use a codebook of prototypical 3D poses which is generated from sample sequences of 3D motion capture data. This idea is in accordance with the concept of equivalence classes in action space. Results of the codebook method are presented using the Kinect sensor and the CMU Motion Capture Database.

  20. Combining Front Vehicle Detection with 3D Pose Estimation for a Better Driver Assistance

    Directory of Open Access Journals (Sweden)

    Yu Peng

    2012-09-01

    Full Text Available Driver assistant systems enhance traffic safety and efficiency. The accurate 3D pose of a front vehicle can help a driver to make the right decision on the road. We propose a novel real-time system to estimate the 3D pose of the front vehicle. This system consists of two parallel threads: vehicle rear tracking and mapping. The vehicle rear is first identified in the video captured by an onboard camera, after license plate localization and foreground extraction. The 3D pose estimation technique is then employed with respect to the extracted vehicle rear. Most current 3D pose estimation techniques need prior models or a stereo initialization with user cooperation. It is extremely difficult to obtain prior models due to the varying appearance of vehicles' rears. Moreover, it is unsafe to ask for drivers' cooperation when a vehicle is running. In our system, two initial keyframes for stereo algorithms are automatically extracted by vehicle rear detection and tracking. Map points are defined as a collection of point features extracted from the vehicle's rear with their 3D information. These map points are inferences that relate the 2D features detected in following vehicles' rears with the 3D world. The relative 3D pose of the onboard camera to the front vehicle rear is then estimated through matching the map points with point features detected on the front vehicle rear. We demonstrate the capabilities of our system by testing on real-time and synthesized videos. In order to make the experimental analysis visible, we demonstrated an estimated 3D pose through augmented reality, which needs accurate and real-time 3D pose estimation.

  1. The last Fermat theorem. The story of the riddle that has defied the greatest minds in the world during 358 years

    International Nuclear Information System (INIS)

    Singh, S.

    1998-01-01

    Pierre de Fermat, one of the greatest French mathematician of the seventeenth century, noticed in the margin of his exercise book 'X n + Y n Z n impossible if n upper than 2, i have found a wonderful solution but i am short of place to develop it here'. Only in 1993 a young British man, Andrew Wiles, professor at Princeton, after seven years of work settled this riddle. That is that story that is told here. (N.C.)

  2. Technical difficulties and its remedies in laparoscopic cholecystectomy in situs inversus totalis: A rare case report.

    Science.gov (United States)

    Arya, S V; Das, Anupam; Singh, Sunil; Kalwaniya, Dheer Singh; Sharma, Ashok; Thukral, B B

    2013-01-01

    Laparoscopic cholecystectomy is considered to be the gold standard surgical procedure for cholelithiasis and is one of the commonest surgical procedures in the world today. However, in rare cases of previously undiagnosed situs inversus totalis (with dextrocardia), the presentation of the cholecystitis, its diagnosis and the operative procedure can pose problems. We present here one such case and discuss how the diagnosis was made and difficulties encountered during surgery and how they were coped with. A 35 year old female presented with left hypochondrium pain and dyspepsia, for 2 years. A diagnosis of cholelithiasis with situs inversus was confirmed after thorough clinical examination, abdominal and chest X-rays and ultrasonography of the abdomen. Laparoscopic cholecystectomy, which is the standard treatment, was performed with numerous modifications in the positioning of the monitor, insufflator, ports and the position of the members of the surgical team and the laparoscopic instruments. The patient had an uneventful recovery. Situs inversus totalis is itself a rare condition and when associated with cholelithiasis poses a challenge in the management of the condition. We must appreciate the necessity of setting up the operating theatre, the positioning of the ports, the surgical team and the instruments. Therefore, it becomes important for the right handed surgeons to modify their techniques and establish a proper hand eye coordination to adapt to the mirror image anatomy of the Calot's triangle in a patient of situs inversus totalis. Copyright © 2013 Surgical Associates Ltd. Published by Elsevier Ltd. All rights reserved.

  3. Difficulties in emotion regulation and risky driving among Lithuanian drivers.

    Science.gov (United States)

    Šeibokaitė, Laura; Endriulaitienė, Auksė; Sullman, Mark J M; Markšaitytė, Rasa; Žardeckaitė-Matulaitienė, Kristina

    2017-10-03

    Risky driving is a common cause of traffic accidents and injuries. However, there is no clear evidence of how difficulties in emotion regulation contribute to risky driving behavior, particularly in small post-Soviet countries. The present study aimed to investigate the relationship between difficulties in emotion regulation and self-reported risky driving behavior in a sample of Lithuanian drivers. A total of 246 nonprofessional Lithuanian drivers participated in a cross-sectional survey. Difficulties in emotion regulation were assessed using the Difficulties in Emotion Regulation Scale (DERS; Gratz and Roemer 2004), and risky driving behavior was assessed using the Manchester Driver Behaviour Questionnaire (DBQ; Lajunen et al. 2004). Males scored higher than females in aggressive violations and ordinary violations. Females scored higher for the nonacceptance of emotional responses, whereas males had more difficulties with emotional awareness than females. More difficulties in emotion regulation were positively correlated with driving errors, lapses, aggressive violations, and ordinary violations for both males and females. Structural equation modeling showed that difficulties in emotion regulation explained aggressive and ordinary violations more clearly than lapses and errors. When controlling for interactions among the distinct regulation difficulties, difficulties with impulse control and difficulties engaging in goal-directed behavior predicted risky driving. Furthermore, nonacceptance of emotional responses and limited access to emotion regulation strategies were related to less violations and more driving errors. Emotion regulation difficulties were associated with the self-reported risky driving behaviors of Lithuanian drivers. This provides useful hints for improving driver training programs in order to prevent traffic injuries.

  4. An anti-disturbing real time pose estimation method and system

    Science.gov (United States)

    Zhou, Jian; Zhang, Xiao-hu

    2011-08-01

    Pose estimation relating two-dimensional (2D) images to three-dimensional (3D) rigid object need some known features to track. In practice, there are many algorithms which perform this task in high accuracy, but all of these algorithms suffer from features lost. This paper investigated the pose estimation when numbers of known features or even all of them were invisible. Firstly, known features were tracked to calculate pose in the current and the next image. Secondly, some unknown but good features to track were automatically detected in the current and the next image. Thirdly, those unknown features which were on the rigid and could match each other in the two images were retained. Because of the motion characteristic of the rigid object, the 3D information of those unknown features on the rigid could be solved by the rigid object's pose at the two moment and their 2D information in the two images except only two case: the first one was that both camera and object have no relative motion and camera parameter such as focus length, principle point, and etc. have no change at the two moment; the second one was that there was no shared scene or no matched feature in the two image. Finally, because those unknown features at the first time were known now, pose estimation could go on in the followed images in spite of the missing of known features in the beginning by repeating the process mentioned above. The robustness of pose estimation by different features detection algorithms such as Kanade-Lucas-Tomasi (KLT) feature, Scale Invariant Feature Transform (SIFT) and Speed Up Robust Feature (SURF) were compared and the compact of the different relative motion between camera and the rigid object were discussed in this paper. Graphic Processing Unit (GPU) parallel computing was also used to extract and to match hundreds of features for real time pose estimation which was hard to work on Central Processing Unit (CPU). Compared with other pose estimation methods, this new

  5. The Greatest Show on Earth

    Indian Academy of Sciences (India)

    Darwin and Alfred Russel Wallace: life on earth had evolved ... over long epochs, the pace of change was infinitesimal. ... Thanks to the work of the Japanese theoreti- cian Motoo ... pleasure-minus-expenditure balance is posi- tive. This way of ...

  6. Freedom's Greatest Threat, The Metaterrorist

    National Research Council Canada - National Science Library

    Jones, Gary

    1997-01-01

    The end of the Cold War ushered on to the world scene a new hybrid of terrorist. This new breed of criminal is called the metaterrorist, because his art of instilling terror goes beyond anything we have ever seen in the past...

  7. Climate change: Wilderness's greatest challenge

    Science.gov (United States)

    Nathan L. Stephenson; Connie Millar

    2014-01-01

    Anthropogenic climatic change can no longer be considered an abstract possibility. It is here, its effects are already evident, and changes are expected to accelerate in coming decades, profoundly altering wilderness ecosystems. At the most fundamental level, wilderness stewards will increasingly be confronted with a trade-off between untrammeled wilderness character...

  8. A pose estimation method for unmanned ground vehicles in GPS denied environments

    Science.gov (United States)

    Tamjidi, Amirhossein; Ye, Cang

    2012-06-01

    This paper presents a pose estimation method based on the 1-Point RANSAC EKF (Extended Kalman Filter) framework. The method fuses the depth data from a LIDAR and the visual data from a monocular camera to estimate the pose of a Unmanned Ground Vehicle (UGV) in a GPS denied environment. Its estimation framework continuy updates the vehicle's 6D pose state and temporary estimates of the extracted visual features' 3D positions. In contrast to the conventional EKF-SLAM (Simultaneous Localization And Mapping) frameworks, the proposed method discards feature estimates from the extended state vector once they are no longer observed for several steps. As a result, the extended state vector always maintains a reasonable size that is suitable for online calculation. The fusion of laser and visual data is performed both in the feature initialization part of the EKF-SLAM process and in the motion prediction stage. A RANSAC pose calculation procedure is devised to produce pose estimate for the motion model. The proposed method has been successfully tested on the Ford campus's LIDAR-Vision dataset. The results are compared with the ground truth data of the dataset and the estimation error is ~1.9% of the path length.

  9. Did Buddha turn the other cheek too? A comparison of posing biases between Jesus and Buddha.

    Science.gov (United States)

    Duerksen, Kari N; Friedrich, Trista E; Elias, Lorin J

    2015-10-02

    People tend to exhibit a leftward bias in posing. Various studies suggest that posing to the left portrays a stronger emotion, whereas posing to the right portrays a more neutral emotion. Religions such as Christianity emphasize the role of strong emotions in religious experience, whereas religions such as Buddhism emphasize the calming of emotions as being important. In the present study, we investigated if the emphasis on emotionality of a religion influences the depiction of their religious figures. Specifically, we coded 484 paintings of Jesus and Buddha from online art databases for whether the deity exhibited a left bias, right bias, or central face presentation. The posing biases were analysed to discover whether paintings of Jesus would more frequently depict a leftward bias than paintings of Buddha. Jesus is more commonly depicted with a leftward bias than Buddha, and Buddha is more commonly depicted with a central face presentation than Jesus. These findings support the idea that the amount of emotionality that is to be conveyed in artwork influences the whether the subject is posed with a leftward bias.

  10. Recovering the 3d Pose and Shape of Vehicles from Stereo Images

    Science.gov (United States)

    Coenen, M.; Rottensteiner, F.; Heipke, C.

    2018-05-01

    The precise reconstruction and pose estimation of vehicles plays an important role, e.g. for autonomous driving. We tackle this problem on the basis of street level stereo images obtained from a moving vehicle. Starting from initial vehicle detections, we use a deformable vehicle shape prior learned from CAD vehicle data to fully reconstruct the vehicles in 3D and to recover their 3D pose and shape. To fit a deformable vehicle model to each detection by inferring the optimal parameters for pose and shape, we define an energy function leveraging reconstructed 3D data, image information, the vehicle model and derived scene knowledge. To minimise the energy function, we apply a robust model fitting procedure based on iterative Monte Carlo model particle sampling. We evaluate our approach using the object detection and orientation estimation benchmark of the KITTI dataset (Geiger et al., 2012). Our approach can deal with very coarse pose initialisations and we achieve encouraging results with up to 82 % correct pose estimations. Moreover, we are able to deliver very precise orientation estimation results with an average absolute error smaller than 4°.

  11. Enhancing students’ mathematical problem posing skill through writing in performance tasks strategy

    Science.gov (United States)

    Kadir; Adelina, R.; Fatma, M.

    2018-01-01

    Many researchers have studied the Writing in Performance Task (WiPT) strategy in learning, but only a few paid attention on its relation to the problem-posing skill in mathematics. The problem-posing skill in mathematics covers problem reformulation, reconstruction, and imitation. The purpose of the present study was to examine the effect of WiPT strategy on students’ mathematical problem-posing skill. The research was conducted at a Public Junior Secondary School in Tangerang Selatan. It used a quasi-experimental method with randomized control group post-test. The samples were 64 students consists of 32 students of the experiment group and 32 students of the control. A cluster random sampling technique was used for sampling. The research data were obtained by testing. The research shows that the problem-posing skill of students taught by WiPT strategy is higher than students taught by a conventional strategy. The research concludes that the WiPT strategy is more effective in enhancing the students’ mathematical problem-posing skill compared to the conventional strategy.

  12. Improving attitudes toward mathematics learning with problem posing in class VIII

    Science.gov (United States)

    Vionita, Alfha; Purboningsih, Dyah

    2017-08-01

    This research is classroom action research which is collaborated to improve student's behavior toward math and mathematics learning at class VIII by using problem posing approach. The subject of research is all of students grade VIIIA which consist of 32 students. This research has been held on two period, first period is about 3 times meeting, and second period is about 4 times meeting. The instrument of this research is implementation of learning observation's guidance by using problem posing approach. Cycle test has been used to measure cognitive competence, and questionnaire to measure the students' behavior in mathematics learning process. The result of research shows the students' behavior has been improving after using problem posing approach. It is showed by the behavior's criteria of students that has increasing result from the average in first period to high in second period. Furthermore, the percentage of test result is also improve from 68,75% in first period to 78,13% in second period. On the other hand, the implementation of learning observation by using problem posing approach has also improving and it is showed by the average percentage of teacher's achievement in first period is 89,2% and student's achievement 85,8%. These results get increase in second period for both teacher and students' achievement which are 94,4% and 91,11%. As a result, students' behavior toward math learning process in class VIII has been improving by using problem posing approach.

  13. Single leg balancing in ballet: effects of shoe conditions and poses.

    Science.gov (United States)

    Lobo da Costa, Paula H; Azevedo Nora, Fernanda G S; Vieira, Marcus Fraga; Bosch, Kerstin; Rosenbaum, Dieter

    2013-03-01

    The purpose of this study was to describe the effects of lower limb positioning and shoe conditions on stability levels of selected single leg ballet poses performed in demi-pointe position. Fourteen female non-professional ballet dancers (mean age of 18.4±2.8 years and mean body mass index of 21.5±2.8kg/m(2)) who had practiced ballet for at least seven years, without any musculoskeletal impairment volunteered to participate in this study. A capacitive pressure platform allowed for the assessment of center of pressure variables related to the execution of three single leg ballet poses in demi pointé position: attitude devant, attitude derriére, and attitude a la second. Peak pressures, contact areas, COP oscillation areas, anterior-posterior and medio-lateral COP oscillations and velocities were compared between two shoe conditions (barefoot versus slippers) and among the different poses. Barefoot performances produced more stable poses with significantly higher plantar contact areas, smaller COP oscillation areas and smaller anterior-posterior COP oscillations. COP oscillation areas, anterior-posterior COP oscillations and medio-lateral COP velocities indicated that attitude a la second is the least challenging and attitude derriére the most challenging pose. Copyright © 2012 Elsevier B.V. All rights reserved.

  14. Inertial measurement unit–based iterative pose compensation algorithm for low-cost modular manipulator

    Directory of Open Access Journals (Sweden)

    Yunhan Lin

    2016-01-01

    Full Text Available It is a necessary mean to realize the accurate motion control of the manipulator which uses end-effector pose correction method and compensation method. In this article, first, we established the kinematic model and error model of the modular manipulator (WUST-ARM, and then we discussed the measurement methods and precision of the inertial measurement unit sensor. The inertial measurement unit sensor is mounted on the end-effector of modular manipulator, to get the real-time pose of the end-effector. At last, a new inertial measurement unit–based iterative pose compensation algorithm is proposed. By applying this algorithm in the pose compensation experiment of modular manipulator which is composed of low-cost rotation joints, the results show that the inertial measurement unit can obtain a higher precision when in static state; it will accurately feedback to the control system with an accurate error compensation angle after a brief delay when the end-effector moves to the target point, and after compensation, the precision errors of roll angle, pitch angle, and yaw angle are reached at 0.05°, 0.01°, and 0.27° respectively. It proves that this low-cost method provides a new solution to improve the end-effector pose of low-cost modular manipulator.

  15. Emotional Intelligence, Personality Traits and Career Decision Difficulties

    Science.gov (United States)

    Di Fabio, Annamaria; Palazzeschi, Letizia

    2009-01-01

    This study aims to take an in-depth look at the role of emotional intelligence and personality traits in relation to career decision difficulties. The Italian version of the Career Decision Difficulties Questionnaire (CDDQ), the Bar-On Emotional Quotient Inventory: Short (Bar-On EQ-i: S), and the Big Five Questionnaire (BFQ) were administered to…

  16. Learner's Learning Experiences & Difficulties towards (ESL) among UKM Undergraduates

    Science.gov (United States)

    Maarof, Nooreiny; Munusamy, Indira Malani A/P

    2015-01-01

    This paper aims to investigate the learners learning experiences and difficulties of ESL among the UKM undergraduates. This study will be focusing on identifying the factors behind Malaysian undergraduate's experiences and also their difficulties in the English as Second Language (ESL) classroom. This paper discusses some of the issues of English…

  17. Common Factors Among Family Medicine Residents Who Encounter Difficulty.

    Science.gov (United States)

    Binczyk, Natalia M; Babenko, Oksana; Schipper, Shirley; Ross, Shelley

    2018-04-01

    Residents in difficulty are costly to programs in both time and resources, and encountering difficulty can be emotionally harmful to residents. Approximately 10% of residents will encounter difficulty at some point in training. While there have been several studies looking at common factors among residents who encounter difficulty, some of the findings are inconsistent. The objective of this study was to determine whether there are common factors among the residents who encounter difficulty during training in a large Canadian family medicine residency program. Secondary data analysis was performed on archived resident files from a Canadian family medicine residency program. Residents who commenced an urban family medicine residency program between the years of 2006 and 2014 were included in the study. Five hundred nine family medicine residents were included in data analysis. Residents older than 30 years were 2.33 times (95% CI: 1.27-4.26) more likely to encounter difficulty than residents aged 30 years or younger. Nontransfer residents were 8.85 times (95% CI: 1.17-66.67) more likely to encounter difficulty than transfer residents. The effects of sex, training site, international medical graduate status, and rotation order on the likelihood of encountering difficulty were nonsignificant. Older and nontransfer residents may be facing unique circumstances and may benefit from additional support from the program.

  18. The role of sensorimotor difficulties in autism spectrum conditions

    Directory of Open Access Journals (Sweden)

    Penelope Hannant

    2016-08-01

    Full Text Available AbstractIn addition to difficulties in social communication, current diagnostic criteria for autism spectrum conditions (ASC also incorporate sensorimotor difficulties; repetitive motor movements and atypical reactivity to sensory input (APA, 2013. This paper explores whether sensorimotor difficulties are associated with the development and maintenance of symptoms in ASC. Firstly, studies have shown difficulties coordinating sensory input into planning and executing movement effectively in ASC. Secondly, studies have shown associations between sensory reactivity and motor coordination with core ASC symptoms, suggesting these areas each strongly influence the development of social and communication skills. Thirdly, studies have begun to demonstrate that sensorimotor difficulties in ASC could account for reduced social attention early in development, with a cascading effect on later social, communicative and emotional development. These results suggest that sensorimotor difficulties not only contribute to non-social difficulties such as narrow circumscribed interests, but also to the development of social behaviours such as effectively coordinating eye contact with speech and gesture, interpreting others’ behaviour and responding appropriately. Further research is needed to explore the link between sensory and motor difficulties in ASC, and their contribution to the development and maintenance of ASC.

  19. Assessment of Pragmatic Difficulties and Socioemotional Adjustment in Practice

    Science.gov (United States)

    Farmer, Marion; Oliver, Alice

    2005-01-01

    Background: In professional practice, psychologists and other professionals such as therapists and teachers receive referrals of many children who present with social, emotional and behavioural difficulties that are difficult to understand and assess. The problems of some of these children may stem from pragmatic difficulties in communication.…

  20. A Theoretical Framework towards Understanding of Emotional and Behavioural Difficulties

    Science.gov (United States)

    Poulou, Maria S.

    2014-01-01

    Children's emotional and behavioural difficulties are the result of multiple individual, social and contextual factors working in concert. The current paper proposes a theoretical framework to interpret students' emotional and behavioural difficulties in schools, by taking into consideration teacher-student relationships, students'…

  1. Graphical modeling for item difficulty in medical faculty exams

    African Journals Online (AJOL)

    . Conclusion: The ... difficulty criteria. Key words: Item difficulty, quality control, statistical process control, variable control charts ..... assumed that 68% of the values fall in the interval ± 1.S; .... The balance of the construction of items of exam has ...

  2. Early Writing Deficits in Preschoolers with Oral Language Difficulties

    Science.gov (United States)

    Puranik, Cynthia S.; Lonigan, Christopher J.

    2012-01-01

    The purpose of this study was to investigate whether preschool children with language impairments (LI), a group with documented reading difficulties, also experience writing difficulties. In addition, a purpose was to examine if the writing outcomes differed when children had concomitant cognitive deficits in addition to oral language problems. A…

  3. School Success for Kids with Dyslexia and Other Reading Difficulties

    Science.gov (United States)

    Dunson, Walter E.

    2012-01-01

    "School Success for Kids With Dyslexia and Other Reading Difficulties" provides parents and teachers with goals that will meet the needs of students who are struggling with reading, leading them to work through their difficulties and enjoy reading. It includes information, assessments, and techniques that parents, teachers, and school…

  4. Learning Difficulty and Learner Identity: A Symbiotic Relationship

    Science.gov (United States)

    Hirano, Eliana

    2009-01-01

    This paper reports on a longitudinal case study of an adult EFL learner who perceived himself as having difficulty learning English. Both learning difficulty and learner identity are viewed as being constructed in discursive interactions throughout one's life and, hence, amenable to reconstruction. Data collected from classroom interactions,…

  5. Atomoxetine treatment and ADHD-related difficulties as assessed by adolescent patients, their parents and physicians

    Directory of Open Access Journals (Sweden)

    Lehmann Martin

    2009-08-01

    Full Text Available Abstract Background The degree of ADHD-related difficulties – reflecting overall impairment, social functioning, and quality of life – may be perceived differently by adolescent patients, parents and physicians. The primary aim of this study was to investigate ADHD-related difficulties during atomoxetine treatment, as perceived by the three different raters. Secondary objectives focused on effectiveness and tolerability of atomoxetine treatment in a population of adolescent patients with ADHD. Methods Adolescents with ADHD, aged 12–17 years, received open-label atomoxetine (0.5–1.2 mg/kg/day up to 24 weeks. ADHD-related difficulties at various times of the day were rated using the Global Impression of Perceived Difficulties (GIPD instrument. Inter-rater agreement was analyzed using Cohen's Kappa with 95% confidence intervals (95% CI. ADHD-Rating Scale (ADHD-RS and Clinical Global Impression Severity (GGI-S scores were assessed by the investigator; and spontaneous adverse events, vital signs and laboratory parameters were collected for tolerability assessments. Results 159 patients received atomoxetine. Patients' baseline mean GIPD total ratings were significantly lower than parents' and physicians' scores (12.5 [95%CI 11.6;13.5] vs. 17.2 [16.2;18.2] and 18.8 [17.8;19.8]. For all raters, GIPD scores significantly improved over time. Changes were greatest within the first two weeks. Kappa coefficients varied between 0.186 [0.112;0.259] and 0.662 [0.529;0.795], with strongest agreements between parent and physician assessments, and significant improvements of patient/physician agreements over time (based on 95% CIs. ADHD-RS and CGI-S scores significantly improved over the course of the study (based on 95% CIs. Tolerability results were consistent with earlier reports. Conclusion ADHD-related difficulties were perceived differently by the raters in this open-label trial, but consistently improved during atomoxetine treatment. The GIPD

  6. Increased Difficulties in Managing Stairs in Visually Impaired Older Adults: A Community-Based Survey.

    Directory of Open Access Journals (Sweden)

    Chen-Wei Pan

    Full Text Available Managing stairs is a challenging aspect of daily activities of living for older people. We assessed whether older adults with visual impairment (VI have greater difficulties of managing stairs in daily lives.The study was designed as a community-based cross-sectional study based on a Chinese cohort aged 60 years and older in rural China. Visual acuity (VA was measured in both eyes using a retro-illuminated Snellen chart with tumbling-E optotypes. VI (including blindness was defined as presenting VA of worse than 20/60 in either eye. Having any difficulties in managing stairs was self-reported based on a question drawn from the Barthel Index. Information on participants' socioeconomic status, lifestyle-related factors, diseases histories and medication intake was collected using a questionnaire.The Barthel Index, Activities of Daily Living questionnaire was completed by 4597 (99.7% participants including 2218 men and 2379 women. The age of the participants ranged from 60 to 93 years with a mean of 67.6 ± 6.3 years. In age and gender adjusted models, adults with VI had a higher likelihood of having difficulties in managing stairs (odds ratio [OR] = 2.7; 95% confidence interval [CI] 2.0, 3.7 compared with those without. The association of VI with the likelihood of having difficulties in managing stairs was stronger in older adults who lived alone (OR = 3.2; 95%CI 1.8, 4.5 compared with those who lived with other family members (OR = 2.0; 95%CI 1.3, 4.3. Compared with hypertension, diabetes, obesity and cognitive dysfunction, VI had the greatest impact on people's abilities of managing stairs.VI was associated with an increased likelihood of having difficulties in managing stairs, especially in those who lived alone. However, whether the finding could be extrapolated to other populations warrants further studies as different environmental exposures such as illumination and types of stairs may alter the association observed in this study.

  7. Cloud computing approaches for prediction of ligand binding poses and pathways.

    Science.gov (United States)

    Lawrenz, Morgan; Shukla, Diwakar; Pande, Vijay S

    2015-01-22

    We describe an innovative protocol for ab initio prediction of ligand crystallographic binding poses and highly effective analysis of large datasets generated for protein-ligand dynamics. We include a procedure for setup and performance of distributed molecular dynamics simulations on cloud computing architectures, a model for efficient analysis of simulation data, and a metric for evaluation of model convergence. We give accurate binding pose predictions for five ligands ranging in affinity from 7 nM to > 200 μM for the immunophilin protein FKBP12, for expedited results in cases where experimental structures are difficult to produce. Our approach goes beyond single, low energy ligand poses to give quantitative kinetic information that can inform protein engineering and ligand design.

  8. Categorization of questions posed before and after inquiry-based learning

    Directory of Open Access Journals (Sweden)

    Sandra Milena García González

    2014-07-01

    Full Text Available Posing research questions is the central ability of the scientific thought. This article examines the ability of sixth grade children to pose researchable questions before and after a three months’ work on a didactic sequence based on the inquiry school model. According to their purpose, the questions asked by children, after reading a text, were classified into researchable questions -susceptible to be empirically explored-, questions about a cause, and questions on a piece of data. The results show that the amount and the type of questions the students were able to pose during the intervention changed, from most of questions on data or information, to most of researchable questions, subsequently, the importance of designing teaching approaches to foster this ability was proved.

  9. Hierarchical graphical-based human pose estimation via local multi-resolution convolutional neural network

    Science.gov (United States)

    Zhu, Aichun; Wang, Tian; Snoussi, Hichem

    2018-03-01

    This paper addresses the problems of the graphical-based human pose estimation in still images, including the diversity of appearances and confounding background clutter. We present a new architecture for estimating human pose using a Convolutional Neural Network (CNN). Firstly, a Relative Mixture Deformable Model (RMDM) is defined by each pair of connected parts to compute the relative spatial information in the graphical model. Secondly, a Local Multi-Resolution Convolutional Neural Network (LMR-CNN) is proposed to train and learn the multi-scale representation of each body parts by combining different levels of part context. Thirdly, a LMR-CNN based hierarchical model is defined to explore the context information of limb parts. Finally, the experimental results demonstrate the effectiveness of the proposed deep learning approach for human pose estimation.

  10. Hierarchical graphical-based human pose estimation via local multi-resolution convolutional neural network

    Directory of Open Access Journals (Sweden)

    Aichun Zhu

    2018-03-01

    Full Text Available This paper addresses the problems of the graphical-based human pose estimation in still images, including the diversity of appearances and confounding background clutter. We present a new architecture for estimating human pose using a Convolutional Neural Network (CNN. Firstly, a Relative Mixture Deformable Model (RMDM is defined by each pair of connected parts to compute the relative spatial information in the graphical model. Secondly, a Local Multi-Resolution Convolutional Neural Network (LMR-CNN is proposed to train and learn the multi-scale representation of each body parts by combining different levels of part context. Thirdly, a LMR-CNN based hierarchical model is defined to explore the context information of limb parts. Finally, the experimental results demonstrate the effectiveness of the proposed deep learning approach for human pose estimation.

  11. Methods for intraoperative, sterile pose-setting of patient-specific microstereotactic frames

    Science.gov (United States)

    Vollmann, Benjamin; Müller, Samuel; Kundrat, Dennis; Ortmaier, Tobias; Kahrs, Lüder A.

    2015-03-01

    This work proposes new methods for a microstereotactic frame based on bone cement fixation. Microstereotactic frames are under investigation for minimal invasive temporal bone surgery, e.g. cochlear implantation, or for deep brain stimulation, where products are already on the market. The correct pose of the microstereotactic frame is either adjusted outside or inside the operating room and the frame is used for e.g. drill or electrode guidance. We present a patientspecific, disposable frame that allows intraoperative, sterile pose-setting. Key idea of our approach is bone cement between two plates that cures while the plates are positioned with a mechatronics system in the desired pose. This paper includes new designs of microstereotactic frames, a system for alignment and first measurements to analyze accuracy and applicable load.

  12. Feature and Pose Constrained Visual Aided Inertial Navigation for Computationally Constrained Aerial Vehicles

    Science.gov (United States)

    Williams, Brian; Hudson, Nicolas; Tweddle, Brent; Brockers, Roland; Matthies, Larry

    2011-01-01

    A Feature and Pose Constrained Extended Kalman Filter (FPC-EKF) is developed for highly dynamic computationally constrained micro aerial vehicles. Vehicle localization is achieved using only a low performance inertial measurement unit and a single camera. The FPC-EKF framework augments the vehicle's state with both previous vehicle poses and critical environmental features, including vertical edges. This filter framework efficiently incorporates measurements from hundreds of opportunistic visual features to constrain the motion estimate, while allowing navigating and sustained tracking with respect to a few persistent features. In addition, vertical features in the environment are opportunistically used to provide global attitude references. Accurate pose estimation is demonstrated on a sequence including fast traversing, where visual features enter and exit the field-of-view quickly, as well as hover and ingress maneuvers where drift free navigation is achieved with respect to the environment.

  13. Job quality and inequality: parents' jobs and children's emotional and behavioural difficulties.

    Science.gov (United States)

    Strazdins, Lyndall; Shipley, Megan; Clements, Mark; Obrien, Léan V; Broom, Dorothy H

    2010-06-01

    In the context of high and rising rates of parental employment in Australia, we investigated whether poor quality jobs (without security, control, flexibility or paid family leave) could pose a health risk to employed parents' children. We examined the extent to which both mothers' and fathers' jobs matter, and whether disadvantaged children are more vulnerable than others. Multiple regression modelling was used to analyse cross-sectional data for 2004 from the Growing Up in Australia study, a nationally representative sample of 4-5 year old children and their families (N = 2373 employed mothers; 3026 employed fathers). Results revealed that when parents held poor quality jobs their children showed more emotional and behavioural difficulties. The associations with child difficulties were independent of income, parent education, family structure and work hours, and were evident for both mothers' and fathers' jobs. Further, the associations tended to be stronger for children in low-income households and lone-mother families. Thus job quality may be another mechanism underlying the intergenerational transmission of health inequality. Our findings also support the argument that a truly family-friendly job must not erode children's health. Copyright 2010 Elsevier Ltd. All rights reserved.

  14. Restorative justice in Macedonian criminal legislation and difficulties in its implementation

    Directory of Open Access Journals (Sweden)

    Bačanović Oliver

    2010-01-01

    Full Text Available The subject-matter of this paper is to provide an overview of the situation/ status within Macedonian criminal legislation as a concept whose introduction and implementation is of recent time. This issue is addressed at two levels: through the overview of the representation of restorative justice elements within the Macedonian criminal legislation and through foreseeing the difficulties considering the implementation of this concept. Regarding the second level the author especially focuses on the difficulties with which social work centers and local communities have to deal. In order to answer the posed questions the author used his own findings, as well as the findings to which he came during the direct contacts with representatives of respective institutions or on the grounds of materials that these institutions provided. In the conclusion, the author attempts to answer to the closing question: can we be satisfied with the accomplished in the area of restorative justice? The author attempts to answer on the grounds of certain indicators (political will, material assumptions, realized professional trainings and education. The author points out to the necessity of acting in the educational system as well on all levels with an aim to create indispensable critical mass within society that will have an upgraded awareness for peaceful resolution of the conflict situation.

  15. Automatic generation of statistical pose and shape models for articulated joints.

    Science.gov (United States)

    Xin Chen; Graham, Jim; Hutchinson, Charles; Muir, Lindsay

    2014-02-01

    Statistical analysis of motion patterns of body joints is potentially useful for detecting and quantifying pathologies. However, building a statistical motion model across different subjects remains a challenging task, especially for a complex joint like the wrist. We present a novel framework for simultaneous registration and segmentation of multiple 3-D (CT or MR) volumes of different subjects at various articulated positions. The framework starts with a pose model generated from 3-D volumes captured at different articulated positions of a single subject (template). This initial pose model is used to register the template volume to image volumes from new subjects. During this process, the Grow-Cut algorithm is used in an iterative refinement of the segmentation of the bone along with the pose parameters. As each new subject is registered and segmented, the pose model is updated, improving the accuracy of successive registrations. We applied the algorithm to CT images of the wrist from 25 subjects, each at five different wrist positions and demonstrated that it performed robustly and accurately. More importantly, the resulting segmentations allowed a statistical pose model of the carpal bones to be generated automatically without interaction. The evaluation results show that our proposed framework achieved accurate registration with an average mean target registration error of 0.34 ±0.27 mm. The automatic segmentation results also show high consistency with the ground truth obtained semi-automatically. Furthermore, we demonstrated the capability of the resulting statistical pose and shape models by using them to generate a measurement tool for scaphoid-lunate dissociation diagnosis, which achieved 90% sensitivity and specificity.

  16. Structural interface parameters are discriminatory in recognising near-native poses of protein-protein interactions.

    Directory of Open Access Journals (Sweden)

    Sony Malhotra

    Full Text Available Interactions at the molecular level in the cellular environment play a very crucial role in maintaining the physiological functioning of the cell. These molecular interactions exist at varied levels viz. protein-protein interactions, protein-nucleic acid interactions or protein-small molecules interactions. Presently in the field, these interactions and their mechanisms mark intensively studied areas. Molecular interactions can also be studied computationally using the approach named as Molecular Docking. Molecular docking employs search algorithms to predict the possible conformations for interacting partners and then calculates interaction energies. However, docking proposes number of solutions as different docked poses and hence offers a serious challenge to identify the native (or near native structures from the pool of these docked poses. Here, we propose a rigorous scoring scheme called DockScore which can be used to rank the docked poses and identify the best docked pose out of many as proposed by docking algorithm employed. The scoring identifies the optimal interactions between the two protein partners utilising various features of the putative interface like area, short contacts, conservation, spatial clustering and the presence of positively charged and hydrophobic residues. DockScore was first trained on a set of 30 protein-protein complexes to determine the weights for different parameters. Subsequently, we tested the scoring scheme on 30 different protein-protein complexes and native or near-native structure were assigned the top rank from a pool of docked poses in 26 of the tested cases. We tested the ability of DockScore to discriminate likely dimer interactions that differ substantially within a homologous family and also demonstrate that DOCKSCORE can distinguish correct pose for all 10 recent CAPRI targets.

  17. A deep learning approach for pose estimation from volumetric OCT data.

    Science.gov (United States)

    Gessert, Nils; Schlüter, Matthias; Schlaefer, Alexander

    2018-05-01

    Tracking the pose of instruments is a central problem in image-guided surgery. For microscopic scenarios, optical coherence tomography (OCT) is increasingly used as an imaging modality. OCT is suitable for accurate pose estimation due to its micrometer range resolution and volumetric field of view. However, OCT image processing is challenging due to speckle noise and reflection artifacts in addition to the images' 3D nature. We address pose estimation from OCT volume data with a new deep learning-based tracking framework. For this purpose, we design a new 3D convolutional neural network (CNN) architecture to directly predict the 6D pose of a small marker geometry from OCT volumes. We use a hexapod robot to automatically acquire labeled data points which we use to train 3D CNN architectures for multi-output regression. We use this setup to provide an in-depth analysis on deep learning-based pose estimation from volumes. Specifically, we demonstrate that exploiting volume information for pose estimation yields higher accuracy than relying on 2D representations with depth information. Supporting this observation, we provide quantitative and qualitative results that 3D CNNs effectively exploit the depth structure of marker objects. Regarding the deep learning aspect, we present efficient design principles for 3D CNNs, making use of insights from the 2D deep learning community. In particular, we present Inception3D as a new architecture which performs best for our application. We show that our deep learning approach reaches errors at our ground-truth label's resolution. We achieve a mean average error of 14.89 ± 9.3 µm and 0.096 ± 0.072° for position and orientation learning, respectively. Copyright © 2018 Elsevier B.V. All rights reserved.

  18. Adaptive relative pose control of spacecraft with model couplings and uncertainties

    Science.gov (United States)

    Sun, Liang; Zheng, Zewei

    2018-02-01

    The spacecraft pose tracking control problem for an uncertain pursuer approaching to a space target is researched in this paper. After modeling the nonlinearly coupled dynamics for relative translational and rotational motions between two spacecraft, position tracking and attitude synchronization controllers are developed independently by using a robust adaptive control approach. The unknown kinematic couplings, parametric uncertainties, and bounded external disturbances are handled with adaptive updating laws. It is proved via Lyapunov method that the pose tracking errors converge to zero asymptotically. Spacecraft close-range rendezvous and proximity operations are introduced as an example to validate the effectiveness of the proposed control approach.

  19. A new benchmark for pose estimation with ground truth from virtual reality

    DEFF Research Database (Denmark)

    Schlette, Christian; Buch, Anders Glent; Aksoy, Eren Erdal

    2014-01-01

    The development of programming paradigms for industrial assembly currently gets fresh impetus from approaches in human demonstration and programming-by-demonstration. Major low- and mid-level prerequisites for machine vision and learning in these intelligent robotic applications are pose estimation......, stereo reconstruction and action recognition. As a basis for the machine vision and learning involved, pose estimation is used for deriving object positions and orientations and thus target frames for robot execution. Our contribution introduces and applies a novel benchmark for typical multi...

  20. Robust Pose Estimation using the SwissRanger SR-3000 Camera

    DEFF Research Database (Denmark)

    Gudmundsson, Sigurjon Arni; Larsen, Rasmus; Ersbøll, Bjarne Kjær

    2007-01-01

    In this paper a robust method is presented to classify and estimate an objects pose from a real time range image and a low dimensional model. The model is made from a range image training set which is reduced dimensionally by a nonlinear manifold learning method named Local Linear Embedding (LLE)......). New range images are then projected to this model giving the low dimensional coordinates of the object pose in an efficient manner. The range images are acquired by a state of the art SwissRanger SR-3000 camera making the projection process work in real-time....

  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. University Students with Reading Difficulties: Do Perceived Supports and Comorbid Difficulties Predict Well-being and GPA?

    Science.gov (United States)

    Stack-Cutler, Holly L.; Parrila, Rauno K.; Torppa, Minna

    2016-01-01

    We examined the impact of the number of comorbid difficulties, social support, and community support on life satisfaction and academic achievement among 120 university students or recent graduates with self-reported reading difficulties. Participants completed a questionnaire assessing perceived social support, perceived community support, the…

  3. The Prevalence of Reading Difficulties among Children in Scholar Age

    Directory of Open Access Journals (Sweden)

    Maria Rosita Cecilia

    2014-10-01

    Full Text Available The study investigates the prevalence of reading difficulties among children in scholar age and analyses the socio-demographic characteristics of learners who presented reading difficulties in central Italy. A sample of 623 students 7-11 aged, was assessed with the Italian MT standardized tests. Information on gender, age, handedness, and other socio-demographic variables were also gathered. The study showed that 11% of learners presented poor comprehension skills. The reading speed difficulties were more common than the reading correctness problems: about 7% of children vs 1% were dyslexics due to slow reading. There were no significant differences regarding gender, age. However, dominant hand and the school location seemed to affect the speed difficulties and the comprehension problems. The analyses showed that attending a school located in a rural area was statistically associated with the reading difficulties. Left-handed children were more likely to be slow decoders and/or poor comprehenders. These findings may be used in the early diagnosis of poor readers. These difficulties often have a chronic progression with substantial psychosocial limitations and psychological stress, so children with reading difficulties should be identified as early as possible.

  4. Exploring communication difficulties in pediatric hematology: oncology nurses.

    Science.gov (United States)

    Citak, Ebru Akgun; Toruner, Ebru Kilicarslan; Gunes, Nebahat Bora

    2013-01-01

    Communication plays an important role for the well being of patients, families and also health care professionals in cancer care. Conversely, ineffective communication may cause depression, increased anxiety, hopelessness and decreased of quality life for patients, families and also nurses. This study aimed to explore communication difficulties of pediatric hematology/oncology nurses with patients and their families, as well as their suggestions about communication difficulties. It was conducted in a pediatric hematology/oncology hospital in Ankara, Turkey. Qualitative data were collected by focus groups, with 21 pediatric hematology/oncology nursing staff from three groups. Content analysis was used for data analysis. Findings were grouped in three main categories. The first category concerned communication difficulties, assessing problems in responding to questions, ineffective communication and conflicts with the patient's families. The second was about the effects of communication difficulties on nurses and the last main category involved suggestions for empowering nurses with communication difficulties, the theme being related to institutional issues. Nurses experience communication difficulties with children and their families during long hospital stays. Communication difficulties particularly increase during crisis periods, like at the time of first diagnosis, relapse, the terminal stage or on days with special meaning such as holidays. The results obtained indicate that pediatric nurses and the child/family need to be supported, especially during crisis periods. Feeling of empowerment in communication will improve the quality of care by reducing the feelings of exhaustion and incompetence in nurses.

  5. The Need For ``Pleasure in Finding Things Out:'' The Use of History and Our Greatest Scientists for Human Survival and Scientific Integrity

    Science.gov (United States)

    Borchardt, Joshua

    2011-03-01

    Why Homo sapiens search for interesting things and the methods of which we do so. The use of philosophical, theoretical, and demonstrated processes for exploration of the natural, and not so natural world are presented based on the ideas and wishes of some of History's greatest scientists, with concentration on Richard P. Feynman's lens on scientific discovery and pursuit, for which the abstract gets its title. This talk is presented towards the layman as well as the physicist, and gives insight to the nature of discovery and what it means to have pleasure in finding things out for the betterment of all mankind.

  6. Collaborative Random Faces-Guided Encoders for Pose-Invariant Face Representation Learning.

    Science.gov (United States)

    Shao, Ming; Zhang, Yizhe; Fu, Yun

    2018-04-01

    Learning discriminant face representation for pose-invariant face recognition has been identified as a critical issue in visual learning systems. The challenge lies in the drastic changes of facial appearances between the test face and the registered face. To that end, we propose a high-level feature learning framework called "collaborative random faces (RFs)-guided encoders" toward this problem. The contributions of this paper are three fold. First, we propose a novel supervised autoencoder that is able to capture the high-level identity feature despite of pose variations. Second, we enrich the identity features by replacing the target values of conventional autoencoders with random signals (RFs in this paper), which are unique for each subject under different poses. Third, we further improve the performance of the framework by incorporating deep convolutional neural network facial descriptors and linking discriminative identity features from different RFs for the augmented identity features. Finally, we conduct face identification experiments on Multi-PIE database, and face verification experiments on labeled faces in the wild and YouTube Face databases, where face recognition rate and verification accuracy with Receiver Operating Characteristic curves are rendered. In addition, discussions of model parameters and connections with the existing methods are provided. These experiments demonstrate that our learning system works fairly well on handling pose variations.

  7. A New Pose Estimation Algorithm Using a Perspective-Ray-Based Scaled Orthographic Projection with Iteration.

    Directory of Open Access Journals (Sweden)

    Pengfei Sun

    Full Text Available Pose estimation aims at measuring the position and orientation of a calibrated camera using known image features. The pinhole model is the dominant camera model in this field. However, the imaging precision of this model is not accurate enough for an advanced pose estimation algorithm. In this paper, a new camera model, called incident ray tracking model, is introduced. More importantly, an advanced pose estimation algorithm based on the perspective ray in the new camera model, is proposed. The perspective ray, determined by two positioning points, is an abstract mathematical equivalent of the incident ray. In the proposed pose estimation algorithm, called perspective-ray-based scaled orthographic projection with iteration (PRSOI, an approximate ray-based projection is calculated by a linear system and refined by iteration. Experiments on the PRSOI have been conducted, and the results demonstrate that it is of high accuracy in the six degrees of freedom (DOF motion. And it outperforms three other state-of-the-art algorithms in terms of accuracy during the contrast experiment.

  8. Morozov-type discrepancy principle for nonlinear ill-posed problems ...

    Indian Academy of Sciences (India)

    [3] Engl H W, Kunisch K and Neubauer A, Convergence rates for Tikhonov regularization of nonliner problems, Inverse Problems 5 (1989) 523–540. [4] Hanke M, Neubauer A and Scherzer O, A convergence analysis of Landweber iteration for nonlinear ill-posed problems, Numer. Math. 72 (1995) 21–37. [5] Hofmann B and ...

  9. Perturbation-Based Regularization for Signal Estimation in Linear Discrete Ill-posed Problems

    KAUST Repository

    Suliman, Mohamed Abdalla Elhag; Ballal, Tarig; Al-Naffouri, Tareq Y.

    2016-01-01

    Estimating the values of unknown parameters from corrupted measured data faces a lot of challenges in ill-posed problems. In such problems, many fundamental estimation methods fail to provide a meaningful stabilized solution. In this work, we propose a new regularization approach and a new regularization parameter selection approach for linear least-squares discrete ill-posed problems. The proposed approach is based on enhancing the singular-value structure of the ill-posed model matrix to acquire a better solution. Unlike many other regularization algorithms that seek to minimize the estimated data error, the proposed approach is developed to minimize the mean-squared error of the estimator which is the objective in many typical estimation scenarios. The performance of the proposed approach is demonstrated by applying it to a large set of real-world discrete ill-posed problems. Simulation results demonstrate that the proposed approach outperforms a set of benchmark regularization methods in most cases. In addition, the approach also enjoys the lowest runtime and offers the highest level of robustness amongst all the tested benchmark regularization methods.

  10. Multispectral embedding-based deep neural network for three-dimensional human pose recovery

    Science.gov (United States)

    Yu, Jialin; Sun, Jifeng

    2018-01-01

    Monocular image-based three-dimensional (3-D) human pose recovery aims to retrieve 3-D poses using the corresponding two-dimensional image features. Therefore, the pose recovery performance highly depends on the image representations. We propose a multispectral embedding-based deep neural network (MSEDNN) to automatically obtain the most discriminative features from multiple deep convolutional neural networks and then embed their penultimate fully connected layers into a low-dimensional manifold. This compact manifold can explore not only the optimum output from multiple deep networks but also the complementary properties of them. Furthermore, the distribution of each hierarchy discriminative manifold is sufficiently smooth so that the training process of our MSEDNN can be effectively implemented only using few labeled data. Our proposed network contains a body joint detector and a human pose regressor that are jointly trained. Extensive experiments conducted on four databases show that our proposed MSEDNN can achieve the best recovery performance compared with the state-of-the-art methods.

  11. A problem-posing approach to teaching the topic of radioactivity

    NARCIS (Netherlands)

    Klaassen, C.W.J.M.

    1995-01-01

    This thesis highlights a problem-posing approach to science education. By this is meant an approach that explicitly aims at providing students with content-related motives for extending their existing conceptual resources, experiential base and belief system in a certain direction, such that a

  12. Improving head and body pose estimation through semi-supervised manifold alignment

    KAUST Repository

    Heili, Alexandre; Varadarajan, Jagannadan; Ghanem, Bernard; Ahuja, Narendra; Odobez, Jean-Marc

    2014-01-01

    structure of the features in the train and target data and the need to align them were not explored despite the fact that the pose features between two datasets may vary according to the scene, e.g. due to different camera point of view or perspective

  13. Locating binding poses in protein-ligand systems using reconnaissance metadynamics

    Science.gov (United States)

    Söderhjelm, Pär; Tribello, Gareth A.; Parrinello, Michele

    2012-01-01

    A molecular dynamics-based protocol is proposed for finding and scoring protein-ligand binding poses. This protocol uses the recently developed reconnaissance metadynamics method, which employs a self-learning algorithm to construct a bias that pushes the system away from the kinetic traps where it would otherwise remain. The exploration of phase space with this algorithm is shown to be roughly six to eight times faster than unbiased molecular dynamics and is only limited by the time taken to diffuse about the surface of the protein. We apply this method to the well-studied trypsin–benzamidine system and show that we are able to refind all the poses obtained from a reference EADock blind docking calculation. These poses can be scored based on the length of time the system remains trapped in the pose. Alternatively, one can perform dimensionality reduction on the output trajectory and obtain a map of phase space that can be used in more expensive free-energy calculations. PMID:22440749

  14. Exploiting residual information in the parameter choice for discrete ill-posed problems

    DEFF Research Database (Denmark)

    Hansen, Per Christian; Kilmer, Misha E.; Kjeldsen, Rikke Høj

    2006-01-01

    Most algorithms for choosing the regularization parameter in a discrete ill-posed problem are based on the norm of the residual vector. In this work we propose a different approach, where we seek to use all the information available in the residual vector. We present important relations between...

  15. Pose Self-Measurement of Noncooperative Spacecraft Based on Solar Panel Triangle Structure

    Directory of Open Access Journals (Sweden)

    Jingzhou Song

    2015-01-01

    Full Text Available Aiming at the recognition and location of noncooperative spacecraft, this paper presents a monocular vision pose measurement method based on solar triangle structure. First of all, an autonomous recognition algorithm of feature structure based on sliding window Hough transformation (SWHT and inscribed circle of a triangle is proposed, and the image coordinates of feature points on the triangle can be obtained relying on this algorithm, combined with the P4P algorithm and the structure of spacecraft, calculating the relative pose of target expressed by rotation and translation matrix. The whole algorithm can be loaded into the prewritten onboard program, which will get the autocomplete feature structure extraction and relative pose measurement without human intervention, and this method does not need to mount any markers on the target. Then compare the measured values with the accurate value of the laser tracker, so that a conclusion can be drawn that the maximum position error is lower than 5% and the rotation error is lower than 4%, which meets the requirements of noncooperative spacecraft’s pose measurement for observations, tracking, and docking in the final rendezvous phase.

  16. Morozov-type discrepancy principle for nonlinear ill-posed problems ...

    Indian Academy of Sciences (India)

    For proving the existence of a regularization parameter under a Morozov-type discrepancy principle for Tikhonov regularization of nonlinear ill-posed problems, it is required to impose additional nonlinearity assumptions on the forward operator. Lipschitz continuity of the Freéchet derivative and requirement of the Lipschitz ...

  17. Control and System Theory, Optimization, Inverse and Ill-Posed Problems

    Science.gov (United States)

    1988-09-14

    Justlfleatlen Distribut ion/ Availability Codes # AFOSR-87-0350 Avat’ and/or1987-1988 Dist Special *CONTROL AND SYSTEM THEORY , ~ * OPTIMIZATION, * INVERSE...considerable va- riety of research investigations within the grant areas (Control and system theory , Optimization, and Ill-posed problems]. The

  18. Unintended allergens in precautionary labelled and unlabelled products pose significant risks to UK allergic consumers

    NARCIS (Netherlands)

    Remington, B.C.; Baumert, J.L.; Blom, W.M.; Houben, G.F.; Taylor, S.L.; Kruizinga, A.G.

    2015-01-01

    Background Allergens in food may pose a risk to allergic consumers. While there is EU regulation for allergens present as an ingredient, this is not the case for unintended allergen presence (UAP). Food companies use precautionary allergen labels to inform allergic individuals of a potential risk

  19. Simulation-Based Optimization of Camera Placement in the Context of Industrial Pose Estimation

    DEFF Research Database (Denmark)

    Jørgensen, Troels Bo; Iversen, Thorbjørn Mosekjær; Lindvig, Anders Prier

    2018-01-01

    In this paper, we optimize the placement of a camera in simulation in order to achieve a high success rate for a pose estimation problem. This is achieved by simulating 2D images from a stereo camera in a virtual scene. The stereo images are then used to generate 3D point clouds based on two diff...

  20. A multi-camera system for real-time pose estimation

    Science.gov (United States)

    Savakis, Andreas; Erhard, Matthew; Schimmel, James; Hnatow, Justin

    2007-04-01

    This paper presents a multi-camera system that performs face detection and pose estimation in real-time and may be used for intelligent computing within a visual sensor network for surveillance or human-computer interaction. The system consists of a Scene View Camera (SVC), which operates at a fixed zoom level, and an Object View Camera (OVC), which continuously adjusts its zoom level to match objects of interest. The SVC is set to survey the whole filed of view. Once a region has been identified by the SVC as a potential object of interest, e.g. a face, the OVC zooms in to locate specific features. In this system, face candidate regions are selected based on skin color and face detection is accomplished using a Support Vector Machine classifier. The locations of the eyes and mouth are detected inside the face region using neural network feature detectors. Pose estimation is performed based on a geometrical model, where the head is modeled as a spherical object that rotates upon the vertical axis. The triangle formed by the mouth and eyes defines a vertical plane that intersects the head sphere. By projecting the eyes-mouth triangle onto a two dimensional viewing plane, equations were obtained that describe the change in its angles as the yaw pose angle increases. These equations are then combined and used for efficient pose estimation. The system achieves real-time performance for live video input. Testing results assessing system performance are presented for both still images and video.

  1. Surgical fiducial segmentation and tracking for pose estimation based on ultrasound B-mode images.

    Science.gov (United States)

    Lei Chen; Kuo, Nathanael; Aalamifar, Fereshteh; Narrow, David; Coon, Devin; Prince, Jerry; Boctor, Emad M

    2016-08-01

    Doppler ultrasound is a non-invasive diagnostic tool for the quantitative measurement of blood flow. However, given that it provides velocity data that is dependent on the location and angle of measurement, repeat measurements to detect problems over time may require an expert to return to the same location. We therefore developed an image-guidance system based on ultrasound B-mode images that enables an inexperienced user to position the ultrasound probe at the same site repeatedly in order to acquire a comparable time series of Doppler readings. The system utilizes a bioresorbable fiducial and complementing software composed of the fiducial detection, key points tracking, probe pose estimation, and graphical user interface (GUI) modules. The fiducial is an echogenic marker that is implanted at the surgical site and can be detected and tracked during ultrasound B-mode screening. The key points on the marker can next be used to determine the pose of the ultrasound probe with respect to the marker. The 3D representation of the probe with its position and orientation are then displayed in the GUI for the user guidance. The fiducial detection has been tested on the data sets collected from three animal studies. The pose estimation algorithm was validated by five data sets collected by a UR5 robot. We tested the system on a plastisol phantom and showed that it can detect and track the fiducial marker while displaying the probe pose in real-time.

  2. Comparison On Matching Methods Used In Pose Tracking For 3D Shape Representation

    Directory of Open Access Journals (Sweden)

    Khin Kyu Kyu Win

    2017-01-01

    Full Text Available In this work three different algorithms such as Brute Force Delaunay Triangulation and k-d Tree are analyzed on matching comparison for 3D shape representation. It is intended for developing the pose tracking of moving objects in video surveillance. To determine 3D pose of moving objects some tracking system may require full 3D pose estimation of arbitrarily shaped objects in real time. In order to perform 3D pose estimation in real time each step in the tracking algorithm must be computationally efficient. This paper presents method comparison for the computationally efficient registration of 3D shapes including free-form surfaces. Matching of free-form surfaces are carried out by using geometric point matching algorithm ICP. Several aspects of the ICP algorithm are investigated and analyzed by using specified surface setup. The surface setup processed in this system is represented by simple geometric primitive dealing with objects of free-from shape. Considered representations are a cloud of points.

  3. Towards real-time body pose estimation for presenters in meeting environments

    NARCIS (Netherlands)

    Poppe, Ronald Walter; Heylen, Dirk K.J.; Nijholt, Antinus; Poel, Mannes

    2005-01-01

    This paper describes a computer vision-based approach to body pose estimation. The algorithm can be executed in real-time and processes low resolution, monocular image sequences. A silhouette is extracted and matched against a projection of a 16 DOF human body model. In addition, skin color is used

  4. Hierarchical online appearance-based tracking for 3D head pose, eyebrows, lips, eyelids, and irises

    NARCIS (Netherlands)

    Orozco, Javier; Rudovic, Ognjen; Gonzalez Garcia, Jordi; Pantic, Maja

    In this paper, we propose an On-line Appearance-Based Tracker (OABT) for simultaneous tracking of 3D head pose, lips, eyebrows, eyelids and irises in monocular video sequences. In contrast to previously proposed tracking approaches, which deal with face and gaze tracking separately, our OABT can

  5. Marker detection evaluation by phantom and cadaver experiments for C-arm pose estimation pattern

    Science.gov (United States)

    Steger, Teena; Hoßbach, Martin; Wesarg, Stefan

    2013-03-01

    C-arm fluoroscopy is used for guidance during several clinical exams, e.g. in bronchoscopy to locate the bronchoscope inside the airways. Unfortunately, these images provide only 2D information. However, if the C-arm pose is known, it can be used to overlay the intrainterventional fluoroscopy images with 3D visualizations of airways, acquired from preinterventional CT images. Thus, the physician's view is enhanced and localization of the instrument at the correct position inside the bronchial tree is facilitated. We present a novel method for C-arm pose estimation introducing a marker-based pattern, which is placed on the patient table. The steel markers form a pattern, allowing to deduce the C-arm pose by use of the projective invariant cross-ratio. Simulations show that the C-arm pose estimation is reliable and accurate for translations inside an imaging area of 30 cm x 50 cm and rotations up to 30°. Mean error values are 0.33 mm in 3D space and 0.48 px in the 2D imaging plane. First tests on C-arm images resulted in similarly compelling accuracy values and high reliability in an imaging area of 30 cm x 42.5 cm. Even in the presence of interfering structures, tested both with anatomy phantoms and a turkey cadaver, high success rates over 90% and fully satisfying execution times below 4 sec for 1024 px × 1024 px images could be achieved.

  6. Investigating Mathematics Teachers Candidates' Knowledge about Problem Solving Strategies through Problem Posing

    Science.gov (United States)

    Ünlü, Melihan

    2017-01-01

    The aim of the study was to determine mathematics teacher candidates' knowledge about problem solving strategies through problem posing. This qualitative research was conducted with 95 mathematics teacher candidates studying at education faculty of a public university during the first term of the 2015-2016 academic year in Turkey. Problem Posing…

  7. Foreign-funded M&A Poses No Threatto China’s Economic Security

    Institute of Scientific and Technical Information of China (English)

    王志乐

    2007-01-01

    Foreign funded M■A(Mergers ■ Acquisitions) activity is becoming increasingly common in China.In this article Wang Zhile assesses the effects and risks associated with M■A,finding that foreign funded M■A activity is immensely beneficial to China and poses no threat to economic security.

  8. Development of a Mobile Learning System Based on a Collaborative Problem-Posing Strategy

    Science.gov (United States)

    Sung, Han-Yu; Hwang, Gwo-Jen; Chang, Ya-Chi

    2016-01-01

    In this study, a problem-posing strategy is proposed for supporting collaborative mobile learning activities. Accordingly, a mobile learning environment has been developed, and an experiment on a local culture course has been conducted to evaluate the effectiveness of the proposed approach. Three classes of an elementary school in southern Taiwan…

  9. An Improved Method of Pose Estimation for Lighthouse Base Station Extension.

    Science.gov (United States)

    Yang, Yi; Weng, Dongdong; Li, Dong; Xun, Hang

    2017-10-22

    In 2015, HTC and Valve launched a virtual reality headset empowered with Lighthouse, the cutting-edge space positioning technology. Although Lighthouse is superior in terms of accuracy, latency and refresh rate, its algorithms do not support base station expansion, and is flawed concerning occlusion in moving targets, that is, it is unable to calculate their poses with a small set of sensors, resulting in the loss of optical tracking data. In view of these problems, this paper proposes an improved pose estimation algorithm for cases where occlusion is involved. Our algorithm calculates the pose of a given object with a unified dataset comprising of inputs from sensors recognized by all base stations, as long as three or more sensors detect a signal in total, no matter from which base station. To verify our algorithm, HTC official base stations and autonomous developed receivers are used for prototyping. The experiment result shows that our pose calculation algorithm can achieve precise positioning when a few sensors detect the signal.

  10. Using Online Modelled Spatial Constraints for Pose Estimation in an Industrial Setting

    DEFF Research Database (Denmark)

    Meyer, Kenneth Korsgaard; Wolniakowski, Adam; Hagelskjær, Frederik

    2017-01-01

    We introduce a vision system that is able to on-line learn spatial constraints to improve pose estimation in terms of correct recognition as well as computational speed. By making use of a simulated industrial robot system performing various pick and place tasks, we show the effect of model...

  11. Pose Estimation using a Hierarchical 3D Representation of Contours and Surfaces

    DEFF Research Database (Denmark)

    Buch, Anders Glent; Kraft, Dirk; Kämäräinen, Joni-Kristian

    2013-01-01

    We present a system for detecting the pose of rigid objects using texture and contour information. From a stereo image view of a scene, a sparse hierarchical scene representation is reconstructed using an early cognitive vision system. We define an object model in terms of a simple context...

  12. A Comparison of Iterative 2D-3D Pose Estimation Methods for Real-Time Applications

    DEFF Research Database (Denmark)

    Grest, Daniel; Krüger, Volker; Petersen, Thomas

    2009-01-01

    This work compares iterative 2D-3D Pose Estimation methods for use in real-time applications. The compared methods are available for public as C++ code. One method is part of the openCV library, namely POSIT. Because POSIT is not applicable for planar 3Dpoint congurations, we include the planar P...

  13. Utilizing Semantic Interpretation of Junctions for 3D-2D Pose Estimation

    DEFF Research Database (Denmark)

    Pilz, Florian; Yan, Shi; Grest, Daniel

    2007-01-01

    In this paper we investigate the quality of 3D-2D pose estimates using hand labeled line and point correspondences. We select point correspondences from junctions in the image, allowing to construct a meaningful interpretation about how the junction is formed, as proposed in e.g. [1], [2], [3]. W...

  14. Morozov-type discrepancy principle for nonlinear ill-posed problems ...

    Indian Academy of Sciences (India)

    2016-08-26

    Aug 26, 2016 ... For proving the existence of a regularization parameter under a Morozov-type discrepancy principle for Tikhonov regularization of nonlinear ill-posed problems, it is required to impose additional nonlinearity assumptions on the forward operator. Lipschitz continuity of the Freéchet derivative and requirement ...

  15. Tooth display and lip position during spontaneous and posed smiling in adults.

    NARCIS (Netherlands)

    Geld, P.A.A.M. van der; Oosterveld, P.; Berge, S.J.; Kuijpers-Jagtman, A.M.

    2008-01-01

    OBJECTIVE: To analyze differences in tooth display, lip-line height, and smile width between the posed smiling record, traditionally produced for orthodontic diagnosis, and the spontaneous (Duchenne) smile of joy. MATERIAL AND METHODS: The faces of 122 male participants were each filmed during

  16. Perturbation-Based Regularization for Signal Estimation in Linear Discrete Ill-posed Problems

    KAUST Repository

    Suliman, Mohamed Abdalla Elhag

    2016-11-29

    Estimating the values of unknown parameters from corrupted measured data faces a lot of challenges in ill-posed problems. In such problems, many fundamental estimation methods fail to provide a meaningful stabilized solution. In this work, we propose a new regularization approach and a new regularization parameter selection approach for linear least-squares discrete ill-posed problems. The proposed approach is based on enhancing the singular-value structure of the ill-posed model matrix to acquire a better solution. Unlike many other regularization algorithms that seek to minimize the estimated data error, the proposed approach is developed to minimize the mean-squared error of the estimator which is the objective in many typical estimation scenarios. The performance of the proposed approach is demonstrated by applying it to a large set of real-world discrete ill-posed problems. Simulation results demonstrate that the proposed approach outperforms a set of benchmark regularization methods in most cases. In addition, the approach also enjoys the lowest runtime and offers the highest level of robustness amongst all the tested benchmark regularization methods.

  17. Pose Measurement Method and Experiments for High-Speed Rolling Targets in a Wind Tunnel

    Directory of Open Access Journals (Sweden)

    Zhenyuan Jia

    2014-12-01

    Full Text Available High-precision wind tunnel simulation tests play an important role in aircraft design and manufacture. In this study, a high-speed pose vision measurement method is proposed for high-speed and rolling targets in a supersonic wind tunnel. To obtain images with high signal-to-noise ratio and avoid impacts on the aerodynamic shape of the rolling targets, a high-speed image acquisition method based on ultrathin retro-reflection markers is presented. Since markers are small-sized and some of them may be lost when the target is rolling, a novel markers layout with which markers are distributed evenly on the surface is proposed based on a spatial coding method to achieve highly accurate pose information. Additionally, a pose acquisition is carried out according to the mentioned markers layout after removing mismatching points by Case Deletion Diagnostics. Finally, experiments on measuring the pose parameters of high-speed targets in the laboratory and in a supersonic wind tunnel are conducted to verify the feasibility and effectiveness of the proposed method. Experimental results indicate that the position measurement precision is less than 0.16 mm, the pitching and yaw angle precision less than 0.132° and the roll angle precision 0.712°.

  18. Pose measurement method and experiments for high-speed rolling targets in a wind tunnel.

    Science.gov (United States)

    Jia, Zhenyuan; Ma, Xin; Liu, Wei; Lu, Wenbo; Li, Xiao; Chen, Ling; Wang, Zhengqu; Cui, Xiaochun

    2014-12-12

    High-precision wind tunnel simulation tests play an important role in aircraft design and manufacture. In this study, a high-speed pose vision measurement method is proposed for high-speed and rolling targets in a supersonic wind tunnel. To obtain images with high signal-to-noise ratio and avoid impacts on the aerodynamic shape of the rolling targets, a high-speed image acquisition method based on ultrathin retro-reflection markers is presented. Since markers are small-sized and some of them may be lost when the target is rolling, a novel markers layout with which markers are distributed evenly on the surface is proposed based on a spatial coding method to achieve highly accurate pose information. Additionally, a pose acquisition is carried out according to the mentioned markers layout after removing mismatching points by Case Deletion Diagnostics. Finally, experiments on measuring the pose parameters of high-speed targets in the laboratory and in a supersonic wind tunnel are conducted to verify the feasibility and effectiveness of the proposed method. Experimental results indicate that the position measurement precision is less than 0.16 mm, the pitching and yaw angle precision less than 0.132° and the roll angle precision 0.712°.

  19. Metals and metalloids in PM10 in Nandan County, Guangxi, China, and the health risks posed.

    Science.gov (United States)

    Guo, Guanghui; Song, Bo; Xia, Deshang; Yang, Zijie; Wang, Fopeng

    2018-03-16

    Intense mining, smelting, and tailing activities of polymetallic ore deposits have affected the environment in Nandan County, Guangxi, China. Samples of particulates with aerodynamic diameters low or equal 10 μm (PM 10 ) were collected in Nandan County to investigate the concentrations of and health risks posed by 17 metals and metalloids in the PM 10 . The metal and metalloid concentrations were lower than those found in other industrial cities. The mean Cr concentration was 7.48 ng/m 3 . Significant higher metal and metalloid concentrations were found in PM 10 from mining areas (Dachang and Chehe) than from the control area (Liuzhai) (p metalloids in PM 10 at all the sites were low, but the non-carcinogenic risks posed to children by all the metals and metalloids together exceeded the safe level (i.e., risk value > 1). The carcinogenic risks posed by Cd, Ni, and Pb were negligible at all sites, while As, Co, and Cr posed potential carcinogenic risks to the residents.

  20. 21 CFR 740.18 - Coal tar hair dyes posing a risk of cancer.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 7 2010-04-01 2010-04-01 false Coal tar hair dyes posing a risk of cancer. 740.18... (CONTINUED) COSMETICS COSMETIC PRODUCT WARNING STATEMENTS Warning Statements § 740.18 Coal tar hair dyes... coal tar hair dye containing any ingredient listed in paragraph (b) of this section shall bear, in...

  1. Multifactor Analysis of Roadheader’s Body Pose Responses during the Horizontal Cutting Process

    Directory of Open Access Journals (Sweden)

    Kai Zong

    2018-01-01

    Full Text Available Based on the Lagrange equation in system dynamics, aiming at the horizontal cutting process, the dynamical coupling model of boom-type roadheader’s body pose was established. According to input problem of solving the model, a calculation method of the cutting head load was proposed, and the relationship between the cutting head load and pressure of the driving cylinders and swing angle of the cutting arm was obtained through simulating analysis. The simulation model was established to solve the dynamical coupling model. The cutting head load, horizontal swing angle of the cutting arm, and dip angle of coal seam were regarded as independent variables to perform changing parameter analysis in variations of the body pose. The field experiment was carried out, and the measured data is basically consistent with the simulation values. The results show that lateral displacement of the body can reach up to 6.5 cm, backward displacement can reach up to 5.2 cm, floor-based quantity can reach up to 11 cm, pitch angle of the body can reach up to 7.8°, and roll angle can reach up to 2.1°. Variations of the body pose parameters are influenced greatly by the cutting head load, while the influence from horizontal swing angle of the cutting arm and dip angle of coal seam is slighter. Among the pose parameters, floor-based quantity and pitch angle of the body vary relatively greatly, which tend to seriously influence forming quality of the roadway and should be mainly considered in deviation rectification of the roadheader’s body pose.

  2. "Preparatory power posing affects nonverbal presence and job interview performance": Correction to Cuddy et al. (2015).

    Science.gov (United States)

    2018-05-01

    Reports an error in "Preparatory power posing affects nonverbal presence and job interview performance" by Amy J. C. Cuddy, Caroline A. Wilmuth, Andy J. Yap and Dana R. Carney ( Journal of Applied Psychology , 2015[Jul], Vol 100[4], 1286-1295). In the article, the degrees of freedom associated with the three F-tests noted on pages 1289 and 1290 should be 1 and 59 (and not 1 and 60, as previously reported). Also, on p. 1290, in the first sentence under the "Mediation" heading, it should be noted that the dependent variables were regressed onto the mediators, and not the other way around. Finally, in Figures 2 and 3 (on p.interview-preparatory power posing-would enhance performance during the interview. Participants adopted high-power (i.e., expansive, open) poses or low-power (i.e., contractive, closed) poses, and then prepared and delivered a speech to 2 evaluators as part of a mock job interview. All interview speeches were videotaped and coded for overall performance and hireability and for 2 potential mediators: verbal content (e.g., structure, content) and nonverbal presence (e.g., captivating, enthusiastic). As predicted, those who prepared for the job interview with high- (vs. low-) power poses performed better and were more likely to be chosen for hire; this relation was mediated by nonverbal presence, but not by verbal content. Although previous research has focused on how a nonverbal behavior that is enacted during interactions and observed by perceivers affects how those perceivers evaluate and respond to the actor, this experiment focused on how a nonverbal behavior that is enacted before the interaction and unobserved by perceivers affects the actor's performance, which, in turn, affects how perceivers evaluate and respond to the actor. This experiment reveals a theoretically novel and practically informative result that demonstrates the causal relation between preparatory nonverbal behavior and subsequent performance and outcomes. (PsycINFO Database

  3. The rarity of "unusual" [corrected] dispositions of victim bodies: staging and posing.

    Science.gov (United States)

    Keppel, Robert D; Weis, Joseph G

    2004-11-01

    The act of leaving a victim's body in an unusual position is a conscious criminal action by an offender to thwart an investigation, shock the finder and investigators of the crime scene, or give perverted pleasure to the killer. The unusual position concepts of posing and staging a murder victim have been documented thoroughly and have been accepted by the courts as a definable phenomenon. One staging case and one posing case are outlined and reveal characteristics of those homicides. From the Washington State Attorney General's Homicide Investigation and Tracking System's database on murder covering the years 1981-2000 (a total of 5,224 cases), the relative frequency of unusual body dispositions is revealed as a very rare occurrence. Only 1.3% of victims are left in an unusual position, with 0.3% being posed and 0.1% being staged. The characteristics of these types of murders also set them apart: compared to all other murders, in staged murders the victims and killers are, on average, older. All victims and offenders in the staged murders are white, with victims being disproportionately white in murders with any kind of unusual body disposition. Likewise, females stand out as victims when the body is posed, staged, or left in other unusual positions. Whereas posed bodies are more likely to include sexual assault, often in serial murders, there is no evidence of either in the staged cases. Lastly, when a body is left in an unusual position, binding is more likely, as well as the use of more "hands on" means of killing the victim, such as stabbing or cutting weapons, bludgeons, ligatures, or hands and feet.

  4. Task Number and Cognitive Complexity as Determinants of Difficulty ...

    African Journals Online (AJOL)

    PROF. O. E. OSUAGWU

    2013-09-01

    Sep 1, 2013 ... amenable to item analysis and are sample- ... as item difficulty, item discrimination, and .... The aim of this study is to determine: ... and then evaluators will have to pay significant ... calculated and the test statistics were used to.

  5. Teaching chemistry to students with learning difficulties: exemplary ...

    African Journals Online (AJOL)

    Teaching chemistry to students with learning difficulties: exemplary adaptive instructional practices of experienced teachers. ... Arguably, today's science classrooms are witnessing a situation in which students experience a special learning ...

  6. Brain injury and severe eating difficulties at admission

    DEFF Research Database (Denmark)

    Kjærsgaard, Annette; Kaae Kristensen, Hanne

    Objective: The objective of this pilot study was to explore and interpret the way that individuals with acquired brain injury, admitted to inpatient neurorehabilitation with severe eating difficulties, experienced eating nine to fifteen months after discharge. Methods: Four individuals with acqui......Objective: The objective of this pilot study was to explore and interpret the way that individuals with acquired brain injury, admitted to inpatient neurorehabilitation with severe eating difficulties, experienced eating nine to fifteen months after discharge. Methods: Four individuals...... with acquired brain injury were interviewed via qualitative semi-structured interviews. An explorative study was conducted to study eating difficulties. Qualitative content analysis was used. Results: Four main themes emerged from the analysis: personal values related to eating, swallowing difficulties, eating......-of-life. The preliminary findings provide knowledge regarding the patient perspective of adapting to and developing new strategies for activities related to eating, however, further prospective, longitudinal research in a larger scale and with repeated interviews is needed....

  7. Individual difficulties faced by persons with mobility impairments

    CSIR Research Space (South Africa)

    Greeff, M

    2007-07-01

    Full Text Available Disabled persons are experiencing additional difficulties when interacting with systems, applications or devices and also have their own unique requirements that enable them to use a system. If the design of the system does not support...

  8. Reading Comprehension Difficulties among French Students of the ...

    African Journals Online (AJOL)

    Reading Comprehension Difficulties among French Students of the University of Education, Winneba: ... The quality of work done depends so much on the level of understanding of the reading text by students. ... AJOL African Journals Online.

  9. The effectiveness of anger management's training on difficulty of ...

    African Journals Online (AJOL)

    Journal of Fundamental and Applied Sciences ... The purpose of this research is the effect of anger management training on adolescents' emotional regulation. ... Keywords: Anger management, Difficulty in emotion regulation, Adolescent ...

  10. From bureaucratic tot post-bureaucratic: the difficulties of transition

    NARCIS (Netherlands)

    Josserand, E.; Teo, S.; Clegg, S.R.

    2006-01-01

    Purpose - Modern bureaucracies are under reconstruction, bureaucracy being no longer "modern"; they are becoming "post" bureaucratic. Defining the post-bureaucratic organization as a hybrid form provides insight into the intrinsic difficulties involved in the refurbishment of large complex

  11. Orthogonally Evolved AI to Improve Difficulty Adjustment in Video Games

    DEFF Research Database (Denmark)

    Hintze, Arend; Olson, Randal; Lehman, Joel Anthony

    2016-01-01

    Computer games are most engaging when their difficulty is well matched to the player's ability, thereby providing an experience in which the player is neither overwhelmed nor bored. In games where the player interacts with computer-controlled opponents, the difficulty of the game can be adjusted...... not only by changing the distribution of opponents or game resources, but also through modifying the skill of the opponents. Applying evolutionary algorithms to evolve the artificial intelligence that controls opponent agents is one established method for adjusting opponent difficulty. Less-evolved agents...... (i.e. agents subject to fewer generations of evolution) make for easier opponents, while highly-evolved agents are more challenging to overcome. In this publication we test a new approach for difficulty adjustment in games: orthogonally evolved AI, where the player receives support from collaborating...

  12. Communication difficulties in children identified with psychiatric problems

    OpenAIRE

    Helland, Wenche Andersen

    2010-01-01

    Several studies have pointed to an overlap between different developmental psychopathological conditions and language impairments, and difficulties with communication have been identified in children of various diagnostic backgrounds. This thesis is based on three empirical studies, and the purposes are to investigate communication difficulties as reported by parents, in children identified with psychiatric problems as well as to evaluate a Norwegian adaptation of the Children’...

  13. Difficulties in emotion regulation in patients with eating disorders

    OpenAIRE

    Ruscitti, Catherine; Rufino, Katrina; Goodwin, Natalie; Wagner, Rebecca

    2016-01-01

    Background A defining characteristic of eating disorders (EDs) is difficulty with emotion regulation (ER). Previous research indicates that ED subtypes demonstrate differing ER difficulties. Specifically, individuals with Anorexia Nervosa (AN) or Bulimia Nervosa (BN) show greater impairment in their ability to regulate emotions in areas such as achieving goals while upset, reacting impulsively to distress, and effectively using coping strategies, as compared to those with Binge Eating Disorde...

  14. Managing social difficulties: roles and responsibilities of patients and staff.

    Science.gov (United States)

    Wright, Penny; Bingham, Laura; Taylor, Sally; Hanif, Naheed; Podmore, Emma; Velikova, Galina

    2012-01-01

    Implementation of guidance on assessment and management of psychosocial and supportive-care problems or needs will be successful only if consideration is given to existing skills, experience and expectations of staff and patients. This study examines the roles and responsibilities of staff, patients and families in relation to management of social difficulties and proposes a pathway for response. A qualitative study was performed using staff and patient interviews. Seventeen doctors and 16 nurses were interviewed using patient scenarios and a support service questionnaire. Patients (n = 41) completed a screening questionnaire (the Social Difficulties Inventory) and were interviewed. Interviews were audio-recorded, transcribed and subjected to a Framework analysis. Analysis examined (1) actions taken by staff and patients in response to social difficulties, (2) reasons given for action taken and (3) perceptions of staff and patients of who was responsible for taking action. Staff were confident concerning clinically related issues (i.e. mobility) but more hesitant concerning difficulties related to money, work and family concerns. Patients liked to cope with problems on their own where possible, would have liked information or support from staff but were uncertain how to access this. Results led to development of a hierarchy of interventions in response to detected social difficulties. For routine assessment of social difficulties, patients, nurses and doctors will have to work collaboratively, with nurses taking a lead in discussion. For specific clinically related problems doctors would play a more primary role. Copyright © 2010 John Wiley & Sons, Ltd.

  15. Review of student difficulties in upper-level quantum mechanics

    Directory of Open Access Journals (Sweden)

    Chandralekha Singh

    2015-09-01

    Full Text Available [This paper is part of the Focused Collection on Upper Division Physics Courses.] Learning advanced physics, in general, is challenging not only due to the increased mathematical sophistication but also because one must continue to build on all of the prior knowledge acquired at the introductory and intermediate levels. In addition, learning quantum mechanics can be especially challenging because the paradigms of classical mechanics and quantum mechanics are very different. Here, we review research on student reasoning difficulties in learning upper-level quantum mechanics and research on students’ problem-solving and metacognitive skills in these courses. Some of these studies were multiuniversity investigations. The investigations suggest that there is large diversity in student performance in upper-level quantum mechanics regardless of the university, textbook, or instructor, and many students in these courses have not acquired a functional understanding of the fundamental concepts. The nature of reasoning difficulties in learning quantum mechanics is analogous to reasoning difficulties found via research in introductory physics courses. The reasoning difficulties were often due to overgeneralizations of concepts learned in one context to another context where they are not directly applicable. Reasoning difficulties in distinguishing between closely related concepts and in making sense of the formalism of quantum mechanics were common. We conclude with a brief summary of the research-based approaches that take advantage of research on student difficulties in order to improve teaching and learning of quantum mechanics.

  16. 6-DOF Pose Estimation of a Robotic Navigation Aid by Tracking Visual and Geometric Features.

    Science.gov (United States)

    Ye, Cang; Hong, Soonhac; Tamjidi, Amirhossein

    2015-10-01

    This paper presents a 6-DOF Pose Estimation (PE) method for a Robotic Navigation Aid (RNA) for the visually impaired. The RNA uses a single 3D camera for PE and object detection. The proposed method processes the camera's intensity and range data to estimates the camera's egomotion that is then used by an Extended Kalman Filter (EKF) as the motion model to track a set of visual features for PE. A RANSAC process is employed in the EKF to identify inliers from the visual feature correspondences between two image frames. Only the inliers are used to update the EKF's state. The EKF integrates the egomotion into the camera's pose in the world coordinate system. To retain the EKF's consistency, the distance between the camera and the floor plane (extracted from the range data) is used by the EKF as the observation of the camera's z coordinate. Experimental results demonstrate that the proposed method results in accurate pose estimates for positioning the RNA in indoor environments. Based on the PE method, a wayfinding system is developed for localization of the RNA in a home environment. The system uses the estimated pose and the floorplan to locate the RNA user in the home environment and announces the points of interest and navigational commands to the user through a speech interface. This work was motivated by the limitations of the existing navigation technology for the visually impaired. Most of the existing methods use a point/line measurement sensor for indoor object detection. Therefore, they lack capability in detecting 3D objects and positioning a blind traveler. Stereovision has been used in recent research. However, it cannot provide reliable depth data for object detection. Also, it tends to produce a lower localization accuracy because its depth measurement error quadratically increases with the true distance. This paper suggests a new approach for navigating a blind traveler. The method uses a single 3D time-of-flight camera for both 6-DOF PE and 3D object

  17. Textbook Presentations of Weight: Conceptual Difficulties and Language Ambiguities

    Science.gov (United States)

    Taibu, Rex; Rudge, David; Schuster, David

    2015-01-01

    The term "weight" has multiple related meanings in both scientific and everyday usage. Even among experts and in textbooks, weight is ambiguously defined as either the gravitational force on an object or operationally as the magnitude of the force an object exerts on a measuring scale. This poses both conceptual and language difficulties…

  18. The Productive Difficulty of Untranslatables in Qualitative Research

    Science.gov (United States)

    Ruitenberg, Claudia W.; Knowlton, Autumn; Li, Gang

    2016-01-01

    The paper highlights the role of translation in qualitative research that involves multiple languages. Its particular focus is on untranslatables, that is, those words or phrases in a source language that pose challenges to translators because no direct equivalent is available in the target language. "Untranslatables" create moments of…

  19. Reading comprehension difficulties in children with rolandic epilepsy.

    Science.gov (United States)

    Currie, Nicola K; Lew, Adina R; Palmer, Tom M; Basu, Helen; De Goede, Christian; Iyer, Anand; Cain, Kate

    2018-03-01

    Difficulties in reading comprehension can arise from either word reading or listening comprehension difficulties, or a combination of the two. We sought to determine whether children with rolandic epilepsy had poor reading comprehension relative to typically developing comparison children, and whether such difficulties were associated with word reading and/or general language comprehension difficulties. In this cross-sectional study, children with rolandic epilepsy (n=25; 16 males, 9 females; mean age 9y 1mo, SD 1y 7mo) and a comparison group (n=39; 25 males, 14 females; mean age 9y 1mo, SD 1y 3mo) completed assessments of reading comprehension, listening comprehension, word/non-word reading, speech articulation, and Non-verbal IQ. Reading comprehension and word reading were worse in children with rolandic epilepsy (F 1,61 =6.89, p=0.011, ηp2=0.10 and F 1,61 =6.84, p=0.011, ηp2=0.10 respectively), with listening comprehension being marginal (F 1,61 =3.81, p=0.055, ηp2=0.06). Word reading and listening comprehension made large and independent contributions to reading comprehension, explaining 70% of the variance. Children with rolandic epilepsy may be at risk of reading comprehension difficulties. Thorough assessment of individual children is required to ascertain whether the difficulties lie with decoding text, or with general comprehension skills, or both. Children with rolandic epilepsy may be at risk of poor reading comprehension. This was related to poor word reading, poor listening comprehension, or both. Reading comprehension interventions should be tailored to the profile of difficulties. © 2017 Mac Keith Press.

  20. Difficulty buying food, BMI, and eating habits in young children.

    Science.gov (United States)

    Fuller, Anne; Maguire, Jonathon L; Carsley, Sarah; Chen, Yang; Lebovic, Gerald; Omand, Jessica; Parkin, Patricia; Birken, Catherine S

    2018-01-22

    To determine whether parent report of difficulty buying food was associated with child body mass index (BMI) z-score or with eating habits in young children. This was a cross-sectional study in primary care offices in Toronto, Ontario. Subjects were children aged 1-5 years and their caregivers, recruited through the TARGet Kids! Research Network from July 2008 to August 2011. Regression models were developed to test the association between parent report of difficulty buying food because of cost and the following outcomes: child BMI z-score, parent's report of child's intake of fruit and vegetables, fruit juice and sweetened beverages, and fast food. Confounders included child's age, sex, birth weight, maternal BMI, education, ethnicity, immigration status, and neighbourhood income. The study sample consisted of 3333 children. Data on difficulty buying food were available for 3099 children, and 431 of these (13.9%) were from households reporting difficulty buying food. There was no association with child BMI z-score (p = 0.86). Children from households reporting difficulty buying food (compared with never having difficulty buying food) had increased odds of consuming three or fewer servings of fruits and vegetables per day (odds ratio [OR]: 1.31, 95% confidence interval [CI]: 1.03-1.69), more than one serving of fruit juice/sweetened beverage per day (OR: 1.60, 95% CI: 1.28-2.00), and, among children 1-2 years old, one or more servings of fast food per week (OR: 2.91, 95% CI: 1.67-5.08). Parental report of difficulty buying food is associated with less optimal eating habits in children but not with BMI z-score.

  1. The Large Hadron Collider the greatest adventure in town and ten reasons why it matters, as illustrated by the ATLAS experiment

    CERN Document Server

    Millington, Andrew J; MacPherson, Rob; Nordberg, Markus

    2016-01-01

    When the discovery of the Higgs Boson at CERN hit the headlines in 2012, the world was stunned by this achievement of modern science. Less well appreciated, however, were the many ways in which this benefited wider society. The Large Hadron Collider — The Greatest Adventure in Town charts a path through the cultural, economic and medical gains of modern particle physics. It illustrates these messages through the ATLAS experiment at CERN, one of the two big experiments which found the Higgs particle. Moving clear of in-depth physics analysis, it draws on the unparalleled curiosity about particle physics aroused by the Higgs discovery, and relates it to developments familiar in the modern world, including the Internet, its successor "The Grid", and the latest cancer treatments. In this book, advances made from developing the 27 kilometre particle accelerator and its detectors are presented with the benefit of first hand interviews and are extensively illustrated throughout. Interviewees are leading physicis...

  2. Cartesian Control of a 3-DOF Electro-Pneumatic Actuated Motion Platform with Exteroceptive Pose Measurement

    Directory of Open Access Journals (Sweden)

    Eduardo Izaguirre

    2011-09-01

    Full Text Available This paper presents a kinematic cartesian control scheme of 3 degree of freedom parallel robot driven by electro-pneumatic actuators based on exteroceptive pose measurement system. The inverse kinematics model is used to obtain the desired joint position coordinates from the time-varying trajectory given in task space. The proposal cascade control scheme in task space is based in two loops, the inner loop consisting in a decoupled joint position control and the outer loop which is designed to obtain an appropriate task space trajectory tracking. In order to avoid the on-line computation of direct kinematics an arrangement of inertial sensor and optical encoders are employed to provide the accurate pose measurement of end-effector. The experiment's results demonstrate the great performance of the proposed control scheme in industrial motion tracking application.

  3. NUI framework based on real-time head pose estimation and hand gesture recognition

    Directory of Open Access Journals (Sweden)

    Kim Hyunduk

    2016-01-01

    Full Text Available The natural user interface (NUI is used for the natural motion interface without using device or tool such as mice, keyboards, pens and markers. In this paper, we develop natural user interface framework based on two recognition module. First module is real-time head pose estimation module using random forests and second module is hand gesture recognition module, named Hand gesture Key Emulation Toolkit (HandGKET. Using the head pose estimation module, we can know where the user is looking and what the user’s focus of attention is. Moreover, using the hand gesture recognition module, we can also control the computer using the user’s hand gesture without mouse and keyboard. In proposed framework, the user’s head direction and hand gesture are mapped into mouse and keyboard event, respectively.

  4. PRA has many faces - can the safety goal be well-posed

    International Nuclear Information System (INIS)

    Bargmann, H.

    1983-01-01

    The question is discussed whether probabilistic reliability problems can, principally, be well-posed in practical situations. The problem is reduced to the question whether an underlying probabilistic experiment which is, essentially, the set of outcomes can be precisely specified such that the solution of the problem is unique. Upon reexamination of a classical paradox due to Bertrand and consideration of a typical problem of structural reliability we conclude that the possibility of well-posing a reliability problem should be considered illusory, for fundamental reasons which are inherent in practical situations. In particular, it should not be assumed that a quantitative safety goal could be verified. Generally, a probabilistic assessment should be considered as a quantitative method for establishing rational results which should, however, not be viewed as quantitative measures but as qualitative guides

  5. Dynamic Displays Enhance the Ability to Discriminate Genuine and Posed Facial Expressions of Emotion

    Science.gov (United States)

    Namba, Shushi; Kabir, Russell S.; Miyatani, Makoto; Nakao, Takashi

    2018-01-01

    Accurately gauging the emotional experience of another person is important for navigating interpersonal interactions. This study investigated whether perceivers are capable of distinguishing between unintentionally expressed (genuine) and intentionally manipulated (posed) facial expressions attributed to four major emotions: amusement, disgust, sadness, and surprise. Sensitivity to this discrimination was explored by comparing unstaged dynamic and static facial stimuli and analyzing the results with signal detection theory. Participants indicated whether facial stimuli presented on a screen depicted a person showing a given emotion and whether that person was feeling a given emotion. The results showed that genuine displays were evaluated more as felt expressions than posed displays for all target emotions presented. In addition, sensitivity to the perception of emotional experience, or discriminability, was enhanced in dynamic facial displays, but was less pronounced in the case of static displays. This finding indicates that dynamic information in facial displays contributes to the ability to accurately infer the emotional experiences of another person. PMID:29896135

  6. Numerical methods for the design of large-scale nonlinear discrete ill-posed inverse problems

    International Nuclear Information System (INIS)

    Haber, E; Horesh, L; Tenorio, L

    2010-01-01

    Design of experiments for discrete ill-posed problems is a relatively new area of research. While there has been some limited work concerning the linear case, little has been done to study design criteria and numerical methods for ill-posed nonlinear problems. We present an algorithmic framework for nonlinear experimental design with an efficient numerical implementation. The data are modeled as indirect, noisy observations of the model collected via a set of plausible experiments. An inversion estimate based on these data is obtained by a weighted Tikhonov regularization whose weights control the contribution of the different experiments to the data misfit term. These weights are selected by minimization of an empirical estimate of the Bayes risk that is penalized to promote sparsity. This formulation entails a bilevel optimization problem that is solved using a simple descent method. We demonstrate the viability of our design with a problem in electromagnetic imaging based on direct current resistivity and magnetotelluric data

  7. Solving ill-posed control problems by stabilized finite element methods: an alternative to Tikhonov regularization

    Science.gov (United States)

    Burman, Erik; Hansbo, Peter; Larson, Mats G.

    2018-03-01

    Tikhonov regularization is one of the most commonly used methods for the regularization of ill-posed problems. In the setting of finite element solutions of elliptic partial differential control problems, Tikhonov regularization amounts to adding suitably weighted least squares terms of the control variable, or derivatives thereof, to the Lagrangian determining the optimality system. In this note we show that the stabilization methods for discretely ill-posed problems developed in the setting of convection-dominated convection-diffusion problems, can be highly suitable for stabilizing optimal control problems, and that Tikhonov regularization will lead to less accurate discrete solutions. We consider some inverse problems for Poisson’s equation as an illustration and derive new error estimates both for the reconstruction of the solution from the measured data and reconstruction of the source term from the measured data. These estimates include both the effect of the discretization error and error in the measurements.

  8. Underground localization using dual magnetic field sequence measurement and pose graph SLAM for directional drilling

    International Nuclear Information System (INIS)

    Park, Byeolteo; Myung, Hyun

    2014-01-01

    With the development of unconventional gas, the technology of directional drilling has become more advanced. Underground localization is the key technique of directional drilling for real-time path following and system control. However, there are problems such as vibration, disconnection with external infrastructure, and magnetic field distortion. Conventional methods cannot solve these problems in real time or in various environments. In this paper, a novel underground localization algorithm using a re-measurement of the sequence of the magnetic field and pose graph SLAM (simultaneous localization and mapping) is introduced. The proposed algorithm exploits the property of the drilling system that the body passes through the previous pass. By comparing the recorded measurement from one magnetic sensor and the current re-measurement from another magnetic sensor, the proposed algorithm predicts the pose of the drilling system. The performance of the algorithm is validated through simulations and experiments. (paper)

  9. Underground localization using dual magnetic field sequence measurement and pose graph SLAM for directional drilling

    Science.gov (United States)

    Park, Byeolteo; Myung, Hyun

    2014-12-01

    With the development of unconventional gas, the technology of directional drilling has become more advanced. Underground localization is the key technique of directional drilling for real-time path following and system control. However, there are problems such as vibration, disconnection with external infrastructure, and magnetic field distortion. Conventional methods cannot solve these problems in real time or in various environments. In this paper, a novel underground localization algorithm using a re-measurement of the sequence of the magnetic field and pose graph SLAM (simultaneous localization and mapping) is introduced. The proposed algorithm exploits the property of the drilling system that the body passes through the previous pass. By comparing the recorded measurement from one magnetic sensor and the current re-measurement from another magnetic sensor, the proposed algorithm predicts the pose of the drilling system. The performance of the algorithm is validated through simulations and experiments.

  10. A circular feature-based pose measurement method for metal part grasping

    International Nuclear Information System (INIS)

    Wu, Chenrui; He, Zaixing; Zhang, Shuyou; Zhao, Xinyue

    2017-01-01

    The grasping of circular metal parts such as bearings and flanges is a common task in industry. Limited by low texture and repeated features, the point-feature-based method is not applicable in pose measurement of these parts. In this paper, we propose a novel pose measurement method for grasping circular metal parts. This method is based on cone degradation and involves a monocular camera. To achieve higher measurement accuracy, a position-based visual servoing method is presented to continuously control an eye-in-hand, six-degrees-of-freedom robot arm to grasp the part. The uncertainty of the part’s coordinate frame during the control process is solved by defining a fixed virtual coordinate frame. Experimental results are provided to illustrate the effectiveness of the proposed method and the factors that affect measurement accuracy are analyzed. (paper)

  11. Expedition-8 Flight Members Pose Inside the Soyuz TMA-3 Vehicle

    Science.gov (United States)

    2003-01-01

    Posed inside the Soyuz TMA-3 Vehicle in a processing facility at the Baikonur Cosmodrome in Kazakhstan during a pre-launch inspection are (left to right): Expedition-8 Crew members, Michael C. Foale, Mission Commander and NASA ISS Science Officer; Cosmonaut Alexander Y. Kaleri, Soyuz Commander and flight engineer; and European Space Agency (ESA) astronaut Pedro Duque of Spain. The three launched from the Cosmodrome on October 18, 2003 onboard a Soyuz rocket destined for the International Space Station (ISS).

  12. Investigasi Kemampuan Problem Solving dan Problem Posing Matematis Mahasiswa Via Pendekatan Realistic

    OpenAIRE

    Afriansyah, Ekasatya Aldila

    2016-01-01

    Mathematical problem solving and problem posing skill are the mathematical skills that need to be owned by students. By having this skill, students can be more creative in expressing ideas by connecting the knowledge that they held previously. But in reality, there are some students who are lack of problem solving skill; therefore it is really important to improve learning through appropriate approach. Realistic approach had been chosen as the learning theory to be applied in the class. This ...

  13. STS-30 crewmembers pose for informal portrait on JSC FB-SMS middeck

    Science.gov (United States)

    1988-01-01

    STS-30 Atlantis, Orbiter Vehicle (OV) 104, crewmembers pause briefly from their training schedule to pose for informal portrait in JSC fixed base (FB) shuttle mission simulator (SMS). On FB-SMS middeck are (left to right) Commander David M. Walker, Mission Specialist (MS) Mark C. Lee, MS Mary L. Cleave, Pilot Ronald J. Grabe, and MS Norman E. Thagard. FB-SMS is located in JSC's Mission Simulation and Training Facility Bldg 5.

  14. Robustness of Input features from Noisy Silhouettes in Human Pose Estimation

    DEFF Research Database (Denmark)

    Gong, Wenjuan; Fihl, Preben; Gonzàlez, Jordi

    2014-01-01

    . In this paper, we explore this problem. First, We compare performances of several image features widely used for human pose estimation and explore their performances against each other and select one with best performance. Second, iterative closest point algorithm is introduced for a new quantitative...... of silhouette samples of different noise levels and compare with the selected feature on a public dataset: Human Eva dataset....

  15. Right-Hand Side Dependent Bounds for GMRES Applied to Ill-Posed Problems

    KAUST Repository

    Pestana, Jennifer

    2014-01-01

    © IFIP International Federation for Information Processing 2014. In this paper we apply simple GMRES bounds to the nearly singular systems that arise in ill-posed problems. Our bounds depend on the eigenvalues of the coefficient matrix, the right-hand side vector and the nonnormality of the system. The bounds show that GMRES residuals initially decrease, as residual components associated with large eigenvalues are reduced, after which semi-convergence can be expected because of the effects of small eigenvalues.

  16. Does nitrate deposition following astrophysical ionizing radiation events pose an additional threat to amphibians?

    OpenAIRE

    Thomas, Brian C.; Honeyman, Michelle D.

    2008-01-01

    It is known that amphibians are especially susceptible to the combination of heightened UVB radiation and increased nitrate concentrations. Various astrophysical events have been suggested as sources of ionizing radiation that could pose a threat to life on Earth, through destruction of the ozone layer and subsequent increase in UVB, followed by deposition of nitrate. In this study, we investigate whether the nitrate deposition following an ionizing event is sufficiently large to cause an add...

  17. Binocular Vision-Based Position and Pose of Hand Detection and Tracking in Space

    Science.gov (United States)

    Jun, Chen; Wenjun, Hou; Qing, Sheng

    After the study of image segmentation, CamShift target tracking algorithm and stereo vision model of space, an improved algorithm based of Frames Difference and a new space point positioning model were proposed, a binocular visual motion tracking system was constructed to verify the improved algorithm and the new model. The problem of the spatial location and pose of the hand detection and tracking have been solved.

  18. Dr. David Brown poses with a portrait of Ronald McNair

    Science.gov (United States)

    1999-01-01

    In the gymnasium of Ronald McNair Magnet School in Cocoa, Fla., Dr. David Brown, a NASA astronaut, poses with a portrait of NASA astronaut Ronald McNair. The portrait was presented to the school by Walt Disney World during a tribute to McNair. The school had previously been renamed for the fallen astronaut who was one of a crew of seven who lost their lives during an accident following launch of the Space Shuttle Challenger in January 1986.

  19. Mickey Mouse poses with a portrait of Ronald McNair

    Science.gov (United States)

    1999-01-01

    In the gymnasium of Ronald McNair Magnet School in Cocoa, Fla., Mickey Mouse poses with a portrait of NASA astronaut Ronald McNair. The portrait was presented to the school by Walt Disney World during a tribute to McNair. The school had previously been renamed for the fallen astronaut who was one of a crew of seven who lost their lives during an accident following launch of the Space Shuttle Challenger in January 1986.

  20. Simulated Lidar Images of Human Pose using a 3DS Max Virtual Laboratory

    Science.gov (United States)

    2015-12-01

    AFRL-RH-WP-TR-2015-0089 SIMULATED LIDAR IMAGES OF HUMAN POSE USING A 3DS MAX VIRTUAL LABORATORY Jeanne Smith Isiah Davenport Infoscitex Corp...MM-YYYY) 11-12-2015 2. REPORT TYPE Interim 3. DATES COVERED (From - To) March 2013 – April 2015 4. TITLE AND SUBTITLE Simulated LIDAR ...Cleared: 88ABW-2016-0242, 25 January 2016 Report contains color 14. ABSTRACT Large sets of 3D Simulated LIDAR (Light Detection and

  1. Soft tissue navigation for laparoscopic prostatectomy: evaluation of camera pose estimation for enhanced visualization

    Science.gov (United States)

    Baumhauer, M.; Simpfendörfer, T.; Schwarz, R.; Seitel, M.; Müller-Stich, B. P.; Gutt, C. N.; Rassweiler, J.; Meinzer, H.-P.; Wolf, I.

    2007-03-01

    We introduce a novel navigation system to support minimally invasive prostate surgery. The system utilizes transrectal ultrasonography (TRUS) and needle-shaped navigation aids to visualize hidden structures via Augmented Reality. During the intervention, the navigation aids are segmented once from a 3D TRUS dataset and subsequently tracked by the endoscope camera. Camera Pose Estimation methods directly determine position and orientation of the camera in relation to the navigation aids. Accordingly, our system does not require any external tracking device for registration of endoscope camera and ultrasonography probe. In addition to a preoperative planning step in which the navigation targets are defined, the procedure consists of two main steps which are carried out during the intervention: First, the preoperatively prepared planning data is registered with an intraoperatively acquired 3D TRUS dataset and the segmented navigation aids. Second, the navigation aids are continuously tracked by the endoscope camera. The camera's pose can thereby be derived and relevant medical structures can be superimposed on the video image. This paper focuses on the latter step. We have implemented several promising real-time algorithms and incorporated them into the Open Source Toolkit MITK (www.mitk.org). Furthermore, we have evaluated them for minimally invasive surgery (MIS) navigation scenarios. For this purpose, a virtual evaluation environment has been developed, which allows for the simulation of navigation targets and navigation aids, including their measurement errors. Besides evaluating the accuracy of the computed pose, we have analyzed the impact of an inaccurate pose and the resulting displacement of navigation targets in Augmented Reality.

  2. On Landweber–Kaczmarz methods for regularizing systems of ill-posed equations in Banach spaces

    International Nuclear Information System (INIS)

    Leitão, A; Alves, M Marques

    2012-01-01

    In this paper, iterative regularization methods of Landweber–Kaczmarz type are considered for solving systems of ill-posed equations modeled (finitely many) by operators acting between Banach spaces. Using assumptions of uniform convexity and smoothness on the parameter space, we are able to prove a monotony result for the proposed method, as well as to establish convergence (for exact data) and stability results (in the noisy data case). (paper)

  3. Inverse Free Iterative Methods for Nonlinear Ill-Posed Operator Equations

    Directory of Open Access Journals (Sweden)

    Ioannis K. Argyros

    2014-01-01

    ill-posed operator equation F(x=y. The proposed method is a modified form of Tikhonov gradient (TIGRA method considered by Ramlau (2003. The regularization parameter is chosen according to the balancing principle considered by Pereverzev and Schock (2005. The error estimate is derived under a general source condition and is of optimal order. Some numerical examples involving integral equations are also given in this paper.

  4. Satellite markers: a simple method for ground truth car pose on stereo video

    Science.gov (United States)

    Gil, Gustavo; Savino, Giovanni; Piantini, Simone; Pierini, Marco

    2018-04-01

    Artificial prediction of future location of other cars in the context of advanced safety systems is a must. The remote estimation of car pose and particularly its heading angle is key to predict its future location. Stereo vision systems allow to get the 3D information of a scene. Ground truth in this specific context is associated with referential information about the depth, shape and orientation of the objects present in the traffic scene. Creating 3D ground truth is a measurement and data fusion task associated with the combination of different kinds of sensors. The novelty of this paper is the method to generate ground truth car pose only from video data. When the method is applied to stereo video, it also provides the extrinsic camera parameters for each camera at frame level which are key to quantify the performance of a stereo vision system when it is moving because the system is subjected to undesired vibrations and/or leaning. We developed a video post-processing technique which employs a common camera calibration tool for the 3D ground truth generation. In our case study, we focus in accurate car heading angle estimation of a moving car under realistic imagery. As outcomes, our satellite marker method provides accurate car pose at frame level, and the instantaneous spatial orientation for each camera at frame level.

  5. Improving head and body pose estimation through semi-supervised manifold alignment

    KAUST Repository

    Heili, Alexandre

    2014-10-27

    In this paper, we explore the use of a semi-supervised manifold alignment method for domain adaptation in the context of human body and head pose estimation in videos. We build upon an existing state-of-the-art system that leverages on external labelled datasets for the body and head features, and on the unlabelled test data with weak velocity labels to do a coupled estimation of the body and head pose. While this previous approach showed promising results, the learning of the underlying manifold structure of the features in the train and target data and the need to align them were not explored despite the fact that the pose features between two datasets may vary according to the scene, e.g. due to different camera point of view or perspective. In this paper, we propose to use a semi-supervised manifold alignment method to bring the train and target samples closer within the resulting embedded space. To this end, we consider an adaptation set from the target data and rely on (weak) labels, given for example by the velocity direction whenever they are reliable. These labels, along with the training labels are used to bias the manifold distance within each manifold and to establish correspondences for alignment.

  6. Pose control of the chain composed of magnetic particles using external uniform and gradient magnetic fields

    International Nuclear Information System (INIS)

    Zhou, J. F.; Shao, C. L.; Gu, B. Q.

    2016-01-01

    Magnetic particles (MPs) are known to respond to a magnetic field and can be moved by magnetic force, which make them good carriers in bioengineering and pharmaceutical engineering. In this paper, a pose control method for the straight chain composed of MPs is proposed, and the chain with one pose can be moved to another position with another pose using alternately employed uniform and gradient magnetic fields. Based on computer simulations, it is revealed that in the uniform magnetic field, the MPs form a straight chain with the same separation space along the field lines, and once the uniform magnetic field rotates, the chain also rotates with the field. In the gradient magnetic field, the MPs move toward the higher field so that the translation of the chain can be realized. The simulation results indicate that while the uniform magnetic field is rotating, there exists certain hysteresis between the chain and the field, and the chain is not straight anymore. So the uniform magnetic field should rest at the target angle for a period to make the chain fully relax to be straight. For nanoMP, its magnetic moment directly determines the gradient magnetic force which is much smaller than the dipole–dipole force among MPs. Therefore, the translation of the chain is much more time-consuming than rotation. To enlarge the translational velocity, it is suggested to increase the size of MPs or the magnetic field gradient

  7. Pose Self-Calibration of Stereo Vision Systems for Autonomous Vehicle Applications.

    Science.gov (United States)

    Musleh, Basam; Martín, David; Armingol, José María; de la Escalera, Arturo

    2016-09-14

    Nowadays, intelligent systems applied to vehicles have grown very rapidly; their goal is not only the improvement of safety, but also making autonomous driving possible. Many of these intelligent systems are based on making use of computer vision in order to know the environment and act accordingly. It is of great importance to be able to estimate the pose of the vision system because the measurement matching between the perception system (pixels) and the vehicle environment (meters) depends on the relative position between the perception system and the environment. A new method of camera pose estimation for stereo systems is presented in this paper, whose main contribution regarding the state of the art on the subject is the estimation of the pitch angle without being affected by the roll angle. The validation of the self-calibration method is accomplished by comparing it with relevant methods of camera pose estimation, where a synthetic sequence is used in order to measure the continuous error with a ground truth. This validation is enriched by the experimental results of the method in real traffic environments.

  8. Drogue pose estimation for unmanned aerial vehicle autonomous aerial refueling system based on infrared vision sensor

    Science.gov (United States)

    Chen, Shanjun; Duan, Haibin; Deng, Yimin; Li, Cong; Zhao, Guozhi; Xu, Yan

    2017-12-01

    Autonomous aerial refueling is a significant technology that can significantly extend the endurance of unmanned aerial vehicles. A reliable method that can accurately estimate the position and attitude of the probe relative to the drogue is the key to such a capability. A drogue pose estimation method based on infrared vision sensor is introduced with the general goal of yielding an accurate and reliable drogue state estimate. First, by employing direct least squares ellipse fitting and convex hull in OpenCV, a feature point matching and interference point elimination method is proposed. In addition, considering the conditions that some infrared LEDs are damaged or occluded, a missing point estimation method based on perspective transformation and affine transformation is designed. Finally, an accurate and robust pose estimation algorithm improved by the runner-root algorithm is proposed. The feasibility of the designed visual measurement system is demonstrated by flight test, and the results indicate that our proposed method enables precise and reliable pose estimation of the probe relative to the drogue, even in some poor conditions.

  9. ULTOR(Registered TradeMark) Passive Pose and Position Engine For Spacecraft Relative Navigation

    Science.gov (United States)

    Hannah, S. Joel

    2008-01-01

    The ULTOR(Registered TradeMark) Passive Pose and Position Engine (P3E) technology, developed by Advanced Optical Systems, Inc (AOS), uses real-time image correlation to provide relative position and pose data for spacecraft guidance, navigation, and control. Potential data sources include a wide variety of sensors, including visible and infrared cameras. ULTOR(Registered TradeMark) P3E has been demonstrated on a number of host processing platforms. NASA is integrating ULTOR(Registerd TradeMark) P3E into its Relative Navigation System (RNS), which is being developed for the upcoming Hubble Space Telescope (HST) Servicing Mission 4 (SM4). During SM4 ULTOR(Registered TradeMark) P3E will perform realtime pose and position measurements during both the approach and departure phases of the mission. This paper describes the RNS implementation of ULTOR(Registered TradeMark) P3E, and presents results from NASA's hardware-in-the-loop simulation testing against the HST mockup.

  10. Pose Self-Calibration of Stereo Vision Systems for Autonomous Vehicle Applications

    Science.gov (United States)

    Musleh, Basam; Martín, David; Armingol, José María; de la Escalera, Arturo

    2016-01-01

    Nowadays, intelligent systems applied to vehicles have grown very rapidly; their goal is not only the improvement of safety, but also making autonomous driving possible. Many of these intelligent systems are based on making use of computer vision in order to know the environment and act accordingly. It is of great importance to be able to estimate the pose of the vision system because the measurement matching between the perception system (pixels) and the vehicle environment (meters) depends on the relative position between the perception system and the environment. A new method of camera pose estimation for stereo systems is presented in this paper, whose main contribution regarding the state of the art on the subject is the estimation of the pitch angle without being affected by the roll angle. The validation of the self-calibration method is accomplished by comparing it with relevant methods of camera pose estimation, where a synthetic sequence is used in order to measure the continuous error with a ground truth. This validation is enriched by the experimental results of the method in real traffic environments. PMID:27649178

  11. A combined vision-inertial fusion approach for 6-DoF object pose estimation

    Science.gov (United States)

    Li, Juan; Bernardos, Ana M.; Tarrío, Paula; Casar, José R.

    2015-02-01

    The estimation of the 3D position and orientation of moving objects (`pose' estimation) is a critical process for many applications in robotics, computer vision or mobile services. Although major research efforts have been carried out to design accurate, fast and robust indoor pose estimation systems, it remains as an open challenge to provide a low-cost, easy to deploy and reliable solution. Addressing this issue, this paper describes a hybrid approach for 6 degrees of freedom (6-DoF) pose estimation that fuses acceleration data and stereo vision to overcome the respective weaknesses of single technology approaches. The system relies on COTS technologies (standard webcams, accelerometers) and printable colored markers. It uses a set of infrastructure cameras, located to have the object to be tracked visible most of the operation time; the target object has to include an embedded accelerometer and be tagged with a fiducial marker. This simple marker has been designed for easy detection and segmentation and it may be adapted to different service scenarios (in shape and colors). Experimental results show that the proposed system provides high accuracy, while satisfactorily dealing with the real-time constraints.

  12. Pose Self-Calibration of Stereo Vision Systems for Autonomous Vehicle Applications

    Directory of Open Access Journals (Sweden)

    Basam Musleh

    2016-09-01

    Full Text Available Nowadays, intelligent systems applied to vehicles have grown very rapidly; their goal is not only the improvement of safety, but also making autonomous driving possible. Many of these intelligent systems are based on making use of computer vision in order to know the environment and act accordingly. It is of great importance to be able to estimate the pose of the vision system because the measurement matching between the perception system (pixels and the vehicle environment (meters depends on the relative position between the perception system and the environment. A new method of camera pose estimation for stereo systems is presented in this paper, whose main contribution regarding the state of the art on the subject is the estimation of the pitch angle without being affected by the roll angle. The validation of the self-calibration method is accomplished by comparing it with relevant methods of camera pose estimation, where a synthetic sequence is used in order to measure the continuous error with a ground truth. This validation is enriched by the experimental results of the method in real traffic environments.

  13. The Pose Estimation of Mobile Robot Based on Improved Point Cloud Registration

    Directory of Open Access Journals (Sweden)

    Yanzi Miao

    2016-03-01

    Full Text Available Due to GPS restrictions, an inertial sensor is usually used to estimate the location of indoor mobile robots. However, it is difficult to achieve high-accuracy localization and control by inertial sensors alone. In this paper, a new method is proposed to estimate an indoor mobile robot pose with six degrees of freedom based on an improved 3D-Normal Distributions Transform algorithm (3D-NDT. First, point cloud data are captured by a Kinect sensor and segmented according to the distance to the robot. After the segmentation, the input point cloud data are processed by the Approximate Voxel Grid Filter algorithm in different sized voxel grids. Second, the initial registration and precise registration are performed respectively according to the distance to the sensor. The most distant point cloud data use the 3D-Normal Distributions Transform algorithm (3D-NDT with large-sized voxel grids for initial registration, based on the transformation matrix from the odometry method. The closest point cloud data use the 3D-NDT algorithm with small-sized voxel grids for precise registration. After the registrations above, a final transformation matrix is obtained and coordinated. Based on this transformation matrix, the pose estimation problem of the indoor mobile robot is solved. Test results show that this method can obtain accurate robot pose estimation and has better robustness.

  14. Hardware in the Loop Performance Assessment of LIDAR-Based Spacecraft Pose Determination.

    Science.gov (United States)

    Opromolla, Roberto; Fasano, Giancarmine; Rufino, Giancarlo; Grassi, Michele

    2017-09-24

    In this paper an original, easy to reproduce, semi-analytic calibration approach is developed for hardware-in-the-loop performance assessment of pose determination algorithms processing point cloud data, collected by imaging a non-cooperative target with LIDARs. The laboratory setup includes a scanning LIDAR, a monocular camera, a scaled-replica of a satellite-like target, and a set of calibration tools. The point clouds are processed by uncooperative model-based algorithms to estimate the target relative position and attitude with respect to the LIDAR. Target images, acquired by a monocular camera operated simultaneously with the LIDAR, are processed applying standard solutions to the Perspective- n -Points problem to get high-accuracy pose estimates which can be used as a benchmark to evaluate the accuracy attained by the LIDAR-based techniques. To this aim, a precise knowledge of the extrinsic relative calibration between the camera and the LIDAR is essential, and it is obtained by implementing an original calibration approach which does not need ad-hoc homologous targets (e.g., retro-reflectors) easily recognizable by the two sensors. The pose determination techniques investigated by this work are of interest to space applications involving close-proximity maneuvers between non-cooperative platforms, e.g., on-orbit servicing and active debris removal.

  15. A New 3D Object Pose Detection Method Using LIDAR Shape Set.

    Science.gov (United States)

    Kim, Jung-Un; Kang, Hang-Bong

    2018-03-16

    In object detection systems for autonomous driving, LIDAR sensors provide very useful information. However, problems occur because the object representation is greatly distorted by changes in distance. To solve this problem, we propose a LIDAR shape set that reconstructs the shape surrounding the object more clearly by using the LIDAR point information projected on the object. The LIDAR shape set restores object shape edges from a bird's eye view by filtering LIDAR points projected on a 2D pixel-based front view. In this study, we use this shape set for two purposes. The first is to supplement the shape set with a LIDAR Feature map, and the second is to divide the entire shape set according to the gradient of the depth and density to create a 2D and 3D bounding box proposal for each object. We present a multimodal fusion framework that classifies objects and restores the 3D pose of each object using enhanced feature maps and shape-based proposals. The network structure consists of a VGG -based object classifier that receives multiple inputs and a LIDAR-based Region Proposal Networks (RPN) that identifies object poses. It works in a very intuitive and efficient manner and can be extended to other classes other than vehicles. Our research has outperformed object classification accuracy (Average Precision, AP) and 3D pose restoration accuracy (3D bounding box recall rate) based on the latest studies conducted with KITTI data sets.

  16. Camera pose estimation for augmented reality in a small indoor dynamic scene

    Science.gov (United States)

    Frikha, Rawia; Ejbali, Ridha; Zaied, Mourad

    2017-09-01

    Camera pose estimation remains a challenging task for augmented reality (AR) applications. Simultaneous localization and mapping (SLAM)-based methods are able to estimate the six degrees of freedom camera motion while constructing a map of an unknown environment. However, these methods do not provide any reference for where to insert virtual objects since they do not have any information about scene structure and may fail in cases of occlusion of three-dimensional (3-D) map points or dynamic objects. This paper presents a real-time monocular piece wise planar SLAM method using the planar scene assumption. Using planar structures in the mapping process allows rendering virtual objects in a meaningful way on the one hand and improving the precision of the camera pose and the quality of 3-D reconstruction of the environment by adding constraints on 3-D points and poses in the optimization process on the other hand. We proposed to benefit from the 3-D planes rigidity motion in the tracking process to enhance the system robustness in the case of dynamic scenes. Experimental results show that using a constrained planar scene improves our system accuracy and robustness compared with the classical SLAM systems.

  17. Do People With Psychosis Have Specific Difficulties Regulating Emotions?

    Science.gov (United States)

    Lincoln, Tania M; Hartmann, Maike; Köther, Ulf; Moritz, Steffen

    2015-01-01

    Difficulties in emotion regulation (ER) are present in psychotic disorders, but their precise nature is not yet fully understood and it is unclear which difficulties are unique to psychosis compared with other disorders. This study investigated whether ER difficulties in psychosis are more prominent for the ability to modify emotions or for the ability to tolerate and accept them. Furthermore, it investigated whether ER difficulties occur for sadness, anxiety, anger and shame likewise. ER skills were assessed in participants with psychotic disorders (n = 37), participants with depression (n = 30) and healthy controls (n = 28) using the Emotion Regulation Skill Questionnaire that asks participants to rate the intensity of different emotions over the past week and the skills employed to handle each of them. Compared with healthy controls, participants with psychosis showed reduced skills related to awareness, understanding and acceptance of potentially distressing emotions, but not in the ability to modify them. These differences remained significant after controlling for depression. Participants with psychosis showed reduced ER skills in regard to all of the assessed emotions compared with the healthy controls, despite the fact that they only reported sadness as being significantly more intense. The participants with depression showed a similar pattern of ER skills to the psychosis sample, although with a tendency towards even more pronounced difficulties. It is concluded that psychosis is characterized by difficulties in using specific ER skills related to awareness, understanding and acceptance to regulate anger, shame, anxiety and sadness. These difficulties are not unique to psychosis but nevertheless present a promising treatment target. The participants with psychosis found it more difficult to be aware of their emotions, to understand them and to accept them than the healthy control group. However, they reported equal skills when it came to

  18. Undergraduate Students’ Difficulties in Reading and Constructing Phylogenetic Tree

    Science.gov (United States)

    Sa'adah, S.; Tapilouw, F. S.; Hidayat, T.

    2017-02-01

    Representation is a very important communication tool to communicate scientific concepts. Biologists produce phylogenetic representation to express their understanding of evolutionary relationships. The phylogenetic tree is visual representation depict a hypothesis about the evolutionary relationship and widely used in the biological sciences. Phylogenetic tree currently growing for many disciplines in biology. Consequently, learning about phylogenetic tree become an important part of biological education and an interesting area for biology education research. However, research showed many students often struggle with interpreting the information that phylogenetic trees depict. The purpose of this study was to investigate undergraduate students’ difficulties in reading and constructing a phylogenetic tree. The method of this study is a descriptive method. In this study, we used questionnaires, interviews, multiple choice and open-ended questions, reflective journals and observations. The findings showed students experiencing difficulties, especially in constructing a phylogenetic tree. The students’ responds indicated that main reasons for difficulties in constructing a phylogenetic tree are difficult to placing taxa in a phylogenetic tree based on the data provided so that the phylogenetic tree constructed does not describe the actual evolutionary relationship (incorrect relatedness). Students also have difficulties in determining the sister group, character synapomorphy, autapomorphy from data provided (character table) and comparing among phylogenetic tree. According to them building the phylogenetic tree is more difficult than reading the phylogenetic tree. Finding this studies provide information to undergraduate instructor and students to overcome learning difficulties of reading and constructing phylogenetic tree.

  19. Visual difficulty and employment status in the world.

    Directory of Open Access Journals (Sweden)

    Hanen Harrabi

    Full Text Available PURPOSE: Using a world-wide, population-based dataset, we sought to examine the relationship between visual difficulty and employment status. METHODS: The World Health Survey was conducted in 70 countries throughout the world in 2003 using a random, multi-stage, stratified, cluster sampling design. Far vision was assessed by asking about the level of difficulty in seeing and recognizing a person you know across the road (i.e. from a distance of about 20 meters. Responses included none, mild, moderate, severe, or extreme/unable. Participants were asked about their current job, and if they were not working, the reason why (unable to find job, ill health, homemaker, studies, unpaid work, other. The occupation in the last 12 months was obtained. Multinomial regression was used accounting for the complex survey design. RESULTS: Of those who wanted to work, 79% of those with severe visual difficulty and 64% of those with extreme visual difficulty were actually working. People who had moderate, severe, or extreme visual difficulty had a higher odds of not working due to an inability to find a job and of not working due to ill health after adjusting for demographic and health factors (P<0.05. CONCLUSIONS: As the major causes of visual impairment in the world are uncorrected refractive error and cataract, countries are losing a great deal of labor productivity by failing to provide for the vision health needs of their citizens and failing to help them integrate into the workforce.

  20. Visual difficulty and employment status in the world.

    Science.gov (United States)

    Harrabi, Hanen; Aubin, Marie-Josee; Zunzunegui, Maria Victoria; Haddad, Slim; Freeman, Ellen E

    2014-01-01

    Using a world-wide, population-based dataset, we sought to examine the relationship between visual difficulty and employment status. The World Health Survey was conducted in 70 countries throughout the world in 2003 using a random, multi-stage, stratified, cluster sampling design. Far vision was assessed by asking about the level of difficulty in seeing and recognizing a person you know across the road (i.e. from a distance of about 20 meters). Responses included none, mild, moderate, severe, or extreme/unable. Participants were asked about their current job, and if they were not working, the reason why (unable to find job, ill health, homemaker, studies, unpaid work, other). The occupation in the last 12 months was obtained. Multinomial regression was used accounting for the complex survey design. Of those who wanted to work, 79% of those with severe visual difficulty and 64% of those with extreme visual difficulty were actually working. People who had moderate, severe, or extreme visual difficulty had a higher odds of not working due to an inability to find a job and of not working due to ill health after adjusting for demographic and health factors (P<0.05). As the major causes of visual impairment in the world are uncorrected refractive error and cataract, countries are losing a great deal of labor productivity by failing to provide for the vision health needs of their citizens and failing to help them integrate into the workforce.

  1. The investigation and implementation of real-time face pose and direction estimation on mobile computing devices

    Science.gov (United States)

    Fu, Deqian; Gao, Lisheng; Jhang, Seong Tae

    2012-04-01

    The mobile computing device has many limitations, such as relative small user interface and slow computing speed. Usually, augmented reality requires face pose estimation can be used as a HCI and entertainment tool. As far as the realtime implementation of head pose estimation on relatively resource limited mobile platforms is concerned, it is required to face different constraints while leaving enough face pose estimation accuracy. The proposed face pose estimation method met this objective. Experimental results running on a testing Android mobile device delivered satisfactory performing results in the real-time and accurately.

  2. Difficulties concerning Diabetes Mellitus Type 1 in children and adolescents

    Directory of Open Access Journals (Sweden)

    Tatiana Rebouças Moreira

    2016-01-01

    Full Text Available Objective: to evaluate the knowledge on diabetes in children and adolescents and the difficulties regarding the disease. Methods: a quantitative study with 40 patients from 6 to 17 years older who were subjected on a questionnaire based on self-care behaviors proposed by the American Association of Diabetes Educators. Results: the average age was 11.6 years with predominance of the female gender (57.5%, most attending grade school (80.0%, naming the parents as primary caregivers (72.5%. Regarding the knowledge about the disease, the item with the highest percentage of errors was about the pathophysiology of Diabetes Mellitus type 1. On the difficulties related to the treatment, food control and application of insulin had higher frequency. Conclusion:the study revealed a high percentage of correct answers among the participants, suggesting knowledge about the disease. Nevertheless, they reported food control and insulin therapy as the main difficulties related to treatment.

  3. DIFFICULTIES IN TEACHING AND LEARNING GRAMMAR IN AN EFL CONTEXT

    Directory of Open Access Journals (Sweden)

    Abdu Mohammed Al-Mekhlafi

    2011-07-01

    Full Text Available The role of grammar instruction in an ESL/EFL context has been for decades a major issue for students and teachers alike. Researchers have debated whether grammar should be taught in the classroom and students, for their part, have generally looked upon grammar instruction as a necessary evil at best, and an avoidable burden at worst. The paper reports a study undertaken to investigate the difficulties teachers face in teaching grammar to EFL students as well as those faced by students in learning it, in the teachers' perception. The study aimed to find out whether there are significant differences in teachers' perceptions of difficulties in relation to their gender, qualification, teaching experience, and the level they teach in school, thus providing insights into their own and their students' difficulties. Mean scores and t-test were used to interpret the data. The main findings are reported with implications.

  4. Divided attention: an undesirable difficulty in memory retention.

    Science.gov (United States)

    Gaspelin, Nicholas; Ruthruff, Eric; Pashler, Harold

    2013-10-01

    How can we improve memory retention? A large body of research has suggested that difficulty encountered during learning, such as when practice sessions are distributed rather than massed, can enhance later memory performance (see R. A. Bjork & E. L. Bjork, 1992). Here, we investigated whether divided attention during retrieval practice can also constitute a desirable difficulty. Following two initial study phases and one test phase with Swahili-English word pairs (e.g., vuvi-snake), we manipulated whether items were tested again under full or divided attention. Two days later, participants were brought back for a final cued-recall test (e.g., vuvi-?). Across three experiments (combined N = 122), we found no evidence that dividing attention while practicing retrieval enhances memory retention. This finding raises the question of why many types of difficulty during practice do improve long-term retention, but dividing attention does not.

  5. Psychosocial difficulties from the perspective of persons with neuropsychiatric disorders.

    Science.gov (United States)

    Coenen, Michaela; Cabello, Maria; Umlauf, Silvia; Ayuso-Mateos, José Luis; Anczewska, Marta; Tourunen, Jouni; Leonardi, Matilde; Cieza, Alarcos

    2016-01-01

    The objective of this study is to determine whether persons with neuropsychiatric disorders experience a common set of psychosocial difficulties using qualitative data from focus groups and individual interviews. The study was performed in five European countries (Finland, Italy, Germany, Poland and Spain) using the focus groups and individual interviews with persons with nine neuropsychiatric disorders (dementia, depression, epilepsy, migraine, multiple sclerosis, Parkinson's disease, schizophrenia, stroke and substance dependence). Digitally recorded sessions were analysed using a step-by-step qualitative and quantitative methodology resulting in the compilation of a common set of psychosocial difficulties using the International Classification of Functioning, Disability and Health (ICF) as a framework. Sixty-seven persons participated in the study. Most persons with neuropsychiatric disorders experience difficulties in emotional functions, sleeping, carrying out daily routine, working and interpersonal relationships in common. Sixteen out of 33 psychosocial difficulties made up the common set. This set includes mental functions, pain and issues addressing activities and participation and provides first evidence for the hypothesis of horizontal epidemiology of psychosocial difficulties in neuropsychiatric disorders. This study provides information about psychosocial difficulties that should be covered in the treatment and rehabilitation of persons with neuropsychiatric disorders regardless of clinical diagnoses. Emotional problems, work and sleep problems should be addressed in all the treatments of neuropsychiatric disorders regardless of their specific diagnosis, etiology and severity. Personality issues should be targeted in the treatment for neurological disorders, whereas communication skill training may also be useful for mental disorders. The effects of medication and social environment on patient's daily life should be considered in all the

  6. Navigation skill impairment: Another dimension of the driving difficulties in minimal hepatic encephalopathy.

    Science.gov (United States)

    Bajaj, Jasmohan S; Hafeezullah, Muhammad; Hoffmann, Raymond G; Varma, Rajiv R; Franco, Jose; Binion, David G; Hammeke, Thomas A; Saeian, Kia

    2008-02-01

    Patients with minimal hepatic encephalopathy (MHE) have attention, response inhibition, and working memory difficulties that are associated with driving impairment and high motor vehicle accident risk. Navigation is a complex system needed for safe driving that requires functioning working memory and other domains adversely affected by MHE. The aim of this study was to determine the effect of MHE on navigation skills and correlate them with psychometric impairment. Forty-nine nonalcoholic patients with cirrhosis (34 MHE+, 15 MHE-; divided on the basis of a battery of block design, digit symbol, and number connection test A) and 48 age/education-matched controls were included. All patients underwent the psychometric battery and inhibitory control test (ICT) (a test of response inhibition) and driving simulation. Driving simulation consisted of 4 parts: (1) training; (2) driving (outcome being accidents); (3) divided attention (outcome being missed tasks); and (4) navigation, driving along a marked path on a map in a "virtual city" (outcome being illegal turns). Illegal turns were significantly higher in MHE+ (median 1; P = 0.007) compared with MHE-/controls (median 0). Patients who were MHE+ missed more divided attention tasks compared with others (median MHE+ 1, MHE-/controls 0; P = 0.001). Similarly, accidents were higher in patients who were MHE+ (median 2.5; P = 0.004) compared with MHE- (median 1) or controls (median 2). Accidents and illegal turns were significantly correlated (P = 0.001, r = 0.51). ICT impairment was the test most correlated with illegal turns (r = 0.6) and accidents (r = 0.44), although impairment on the other tests were also correlated with illegal turns. Patients positive for MHE have impaired navigation skills on a driving simulator, which is correlated with impairment in response inhibition (ICT) and attention. This navigation difficulty may pose additional driving problems, compounding the pre-existing deleterious effect of attention

  7. 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)

  8. Penalized linear regression for discrete ill-posed problems: A hybrid least-squares and mean-squared error approach

    KAUST Repository

    Suliman, Mohamed Abdalla Elhag; Ballal, Tarig; Kammoun, Abla; Al-Naffouri, Tareq Y.

    2016-01-01

    This paper proposes a new approach to find the regularization parameter for linear least-squares discrete ill-posed problems. In the proposed approach, an artificial perturbation matrix with a bounded norm is forced into the discrete ill-posed model

  9. Absolute stability results for well-posed infinite-dimensional systems with applications to low-gain integral control

    NARCIS (Netherlands)

    Logemann, H; Curtain, RF

    2000-01-01

    We derive absolute stability results for well-posed infinite-dimensional systems which, in a sense, extend the well-known circle criterion to the case that the underlying linear system is the series interconnection of an exponentially stable well-posed infinite-dimensional system and an integrator

  10. Multi-view 3D human pose estimation combining single-frame recovery, temporal integration and model adaptation

    NARCIS (Netherlands)

    Hofmann, K.M.; Gavrilla, D.M.

    2009-01-01

    We present a system for the estimation of unconstrained 3D human upper body movement from multiple cameras. Its main novelty lies in the integration of three components: single frame pose recovery, temporal integration and model adaptation. Single frame pose recovery consists of a hypothesis

  11. Self-Organizing Neural Integration of Pose-Motion Features for Human Action Recognition

    Directory of Open Access Journals (Sweden)

    German Ignacio Parisi

    2015-06-01

    Full Text Available The visual recognition of complex, articulated human movements is fundamental for a wide range of artificial systems oriented towards human-robot communication, action classification, and action-driven perception. These challenging tasks may generally involve the processing of a huge amount of visual information and learning-based mechanisms for generalizing a set of training actions and classifying new samples. To operate in natural environments, a crucial property is the efficient and robust recognition of actions, also under noisy conditions caused by, for instance, systematic sensor errors and temporarily occluded persons. Studies of the mammalian visual system and its outperforming ability to process biological motion information suggest separate neural pathways for the distinct processing of pose and motion features at multiple levels and the subsequent integration of these visual cues for action perception. We present a neurobiologically-motivated approach to achieve noise-tolerant action recognition in real time. Our model consists of self-organizing Growing When Required (GWR networks that obtain progressively generalized representations of sensory inputs and learn inherent spatiotemporal dependencies. During the training, the GWR networks dynamically change their topological structure to better match the input space. We first extract pose and motion features from video sequences and then cluster actions in terms of prototypical pose-motion trajectories. Multi-cue trajectories from matching action frames are subsequently combined to provide action dynamics in the joint feature space. Reported experiments show that our approach outperforms previous results on a dataset of full-body actions captured with a depth sensor, and ranks among the best 21 results for a public benchmark of domestic daily actions.

  12. Segmentation, classification, and pose estimation of military vehicles in low resolution laser radar images

    Science.gov (United States)

    Neulist, Joerg; Armbruster, Walter

    2005-05-01

    Model-based object recognition in range imagery typically involves matching the image data to the expected model data for each feasible model and pose hypothesis. Since the matching procedure is computationally expensive, the key to efficient object recognition is the reduction of the set of feasible hypotheses. This is particularly important for military vehicles, which may consist of several large moving parts such as the hull, turret, and gun of a tank, and hence require an eight or higher dimensional pose space to be searched. The presented paper outlines techniques for reducing the set of feasible hypotheses based on an estimation of target dimensions and orientation. Furthermore, the presence of a turret and a main gun and their orientations are determined. The vehicle parts dimensions as well as their error estimates restrict the number of model hypotheses whereas the position and orientation estimates and their error bounds reduce the number of pose hypotheses needing to be verified. The techniques are applied to several hundred laser radar images of eight different military vehicles with various part classifications and orientations. On-target resolution in azimuth, elevation and range is about 30 cm. The range images contain up to 20% dropouts due to atmospheric absorption. Additionally some target retro-reflectors produce outliers due to signal crosstalk. The presented algorithms are extremely robust with respect to these and other error sources. The hypothesis space for hull orientation is reduced to about 5 degrees as is the error for turret rotation and gun elevation, provided the main gun is visible.

  13. An Inertial and Optical Sensor Fusion Approach for Six Degree-of-Freedom Pose Estimation

    Science.gov (United States)

    He, Changyu; Kazanzides, Peter; Sen, Hasan Tutkun; Kim, Sungmin; Liu, Yue

    2015-01-01

    Optical tracking provides relatively high accuracy over a large workspace but requires line-of-sight between the camera and the markers, which may be difficult to maintain in actual applications. In contrast, inertial sensing does not require line-of-sight but is subject to drift, which may cause large cumulative errors, especially during the measurement of position. To handle cases where some or all of the markers are occluded, this paper proposes an inertial and optical sensor fusion approach in which the bias of the inertial sensors is estimated when the optical tracker provides full six degree-of-freedom (6-DOF) pose information. As long as the position of at least one marker can be tracked by the optical system, the 3-DOF position can be combined with the orientation estimated from the inertial measurements to recover the full 6-DOF pose information. When all the markers are occluded, the position tracking relies on the inertial sensors that are bias-corrected by the optical tracking system. Experiments are performed with an augmented reality head-mounted display (ARHMD) that integrates an optical tracking system (OTS) and inertial measurement unit (IMU). Experimental results show that under partial occlusion conditions, the root mean square errors (RMSE) of orientation and position are 0.04° and 0.134 mm, and under total occlusion conditions for 1 s, the orientation and position RMSE are 0.022° and 0.22 mm, respectively. Thus, the proposed sensor fusion approach can provide reliable 6-DOF pose under long-term partial occlusion and short-term total occlusion conditions. PMID:26184191

  14. 6DoF object pose measurement by a monocular manifold-based pattern recognition technique

    International Nuclear Information System (INIS)

    Kouskouridas, Rigas; Charalampous, Konstantinos; Gasteratos, Antonios

    2012-01-01

    In this paper, a novel solution to the compound problem of object recognition and 3D pose estimation is presented. An accurate measurement of the geometrical configuration of a recognized target, relative to a known coordinate system, is of fundamental importance and constitutes a prerequisite for several applications such as robot grasping or obstacle avoidance. The proposed method lays its foundations on the following assumptions: (a) the same object captured under varying viewpoints and perspectives represents data that could be projected onto a well-established and highly distinguishable subspace; (b) totally different objects observed under the same viewpoints and perspectives share identical 3D pose that can be sufficiently modeled to produce a generalized model. Toward this end, we propose an advanced architecture that allows both recognizing patterns and providing efficient solution for 6DoF pose estimation. We employ a manifold modeling architecture that is grounded on a part-based representation of an object, which in turn, is accomplished via an unsupervised clustering of the extracted visual cues. The main contributions of the proposed framework are: (a) the proposed part-based architecture requires minimum supervision, compared to other contemporary solutions, whilst extracting new features encapsulating both appearance and geometrical attributes of the objects; (b) contrary to related projects that extract high-dimensional data, thus, increasing the complexity of the system, the proposed manifold modeling approach makes use of low dimensionality input vectors; (c) the formulation of a novel input–output space mapping that outperforms the existing dimensionality reduction schemes. Experimental results justify our theoretical claims and demonstrate the superiority of our method comparing to other related contemporary projects. (paper)

  15. The Dynamic Features of Lip Corners in Genuine and Posed Smiles

    Directory of Open Access Journals (Sweden)

    Hui Guo

    2018-02-01

    Full Text Available The smile is a frequently expressed facial expression that typically conveys a positive emotional state and friendly intent. However, human beings have also learned how to fake smiles, typically by controlling the mouth to provide a genuine-looking expression. This is often accompanied by inaccuracies that can allow others to determine that the smile is false. Mouth movement is one of the most striking features of the smile, yet our understanding of its dynamic elements is still limited. The present study analyzes the dynamic features of lip corners, and considers how they differ between genuine and posed smiles. Employing computer vision techniques, we investigated elements such as the duration, intensity, speed, symmetry of the lip corners, and certain irregularities in genuine and posed smiles obtained from the UvA-NEMO Smile Database. After utilizing the facial analysis tool OpenFace, we further propose a new approach to segmenting the onset, apex, and offset phases of smiles, as well as a means of measuring irregularities and symmetry in facial expressions. We extracted these features according to 2D and 3D coordinates, and conducted an analysis. The results reveal that genuine smiles have higher values for onset, offset, apex, and total durations, as well as offset displacement, and a variable we termed Irregularity-b (the SD of the apex phase than do posed smiles. Conversely, values tended to be lower for onset and offset Speeds, and Irregularity-a (the rate of peaks, Symmetry-a (the correlation between left and right facial movements, and Symmetry-d (differences in onset frame numbers between the left and right faces. The findings from the present study have been compared to those of previous research, and certain speculations are made.

  16. Delayed Self-Recognition in Autism: A Unique Difficulty?

    Science.gov (United States)

    Dunphy-Lelii, Sarah; Wellman, Henry M.

    2012-01-01

    Achieving a sense of self is a crucial task of ordinary development. With which aspects of self do children with autism have particular difficulty? Two prior studies concluded that children with autism are unimpaired in delayed self-recognition; we confirm and clarify this conclusion by examining it in conjunction with another key aspect of self…

  17. Students' Conceptual Difficulties in Quantum Mechanics: Potential Well Problems

    Science.gov (United States)

    Ozcan, Ozgur; Didis, Nilufer; Tasar, Mehmet Fatih

    2009-01-01

    In this study, students' conceptual difficulties about some basic concepts in quantum mechanics like one-dimensional potential well problems and probability density of tunneling particles were identified. For this aim, a multiple choice instrument named Quantum Mechanics Conceptual Test has been developed by one of the researchers of this study…

  18. Linear Algebra Revisited: An Attempt to Understand Students' Conceptual Difficulties

    Science.gov (United States)

    Britton, Sandra; Henderson, Jenny

    2009-01-01

    This article looks at some of the conceptual difficulties that students have in a linear algebra course. An overview of previous research in this area is given, and the various theories that have been espoused regarding the reasons that students find linear algebra so difficult are discussed. Student responses to two questions testing the ability…

  19. On the difficulties of acquiring mathematical experience: Case rural education

    DEFF Research Database (Denmark)

    Booss-Bavnbek, Bernhelm

    2014-01-01

    Based on a variety of philosophical approaches and my own work for decades in pure and applied mathematics teaching and research, I explain my view upon the basic difficulties of acquiring the “Mathematical Experience” (in the sense of P.J. Davis and R. Hersh 1981) and submit a list of claims how...

  20. Communication difficulties perceived by parents of children with developmental disorders.

    Science.gov (United States)

    Sun, Ingrid Ya I; Fernandes, Fernanda Dreux Miranda

    2014-01-01

    The child's inclusion in his/her social-cultural context is very important to his/her adaptation and well-being. The family has a major role as a facilitator of this process. Therefore the difficulties of these families in communicating with children with communication disorders are an important issue to be assessed in order to support orientations to families. The present study aimed to identify and compare communication difficulties perceived by parents of children with Down Syndrome (DS), Autism Spectrum Disorders (ASD) and Specific Language Impairment (SLI). Information was gathered with the use of a questionnaire with 24 questions regarding the perception of parents about their child communication disorders and the difficulties they identify. The questions were divided into four domains: 1 - Parents' personal difficulties; 2 - Parents' impression about themselves regarding their child; 3 - Parents' impressions about other persons' reactions to their child and 4 - Parents' impression about their child. Sixty parents were the subjects of this study: 20 had children with DS, 20 with SLI and 20 with ASD. All children had ages between 6 and 12 years. It was possible to observe that there was significant difference between the parents of ASD children with those of DS and SLI on the second, third and fourth domains. The questionnaire is effective to the identification of the communication disorders of ASD children based on their parents' reports but not to other developmental disorders.

  1. Magnetic order in graphite: Experimental evidence, intrinsic and extrinsic difficulties

    International Nuclear Information System (INIS)

    Esquinazi, P.; Barzola-Quiquia, J.; Spemann, D.; Rothermel, M.; Ohldag, H.; Garcia, N.; Setzer, A.; Butz, T.

    2010-01-01

    We discuss recently obtained data using different experimental methods including magnetoresistance measurements that indicate the existence of metal-free high-temperature magnetic order in graphite. Intrinsic as well as extrinsic difficulties to trigger magnetic order by irradiation of graphite are discussed in view of recently published theoretical work.

  2. Determining Difficulty of Questions in Intelligent Tutoring Systems

    Science.gov (United States)

    Gunel, Korhan; Asliyan, Rifat

    2009-01-01

    The object of this study is to model the level of a question difficulty by a differential equation at a pre-specified domain knowledge, to be used in an educational support system. For this purpose, we have developed an intelligent tutoring system for mathematics education. Intelligent Tutoring Systems are computer systems designed for improvement…

  3. The Strengths and Difficulties Questionnaire in the Nordic countries

    DEFF Research Database (Denmark)

    Obel, Carsten; Heiervang, Einar; Rodriguez, Alina

    2004-01-01

    BACKGROUND: The Strengths and Difficulties Questionnaire (SDQ) has been translated into the different Nordic languages between 1996 and 2003. During the past few years, SDQs have been completed for nearly 100,000 children and adolescents in population-based studies as well as in clinical samples...

  4. Beyond Stigmatization of Children with Difficulties in Learning

    Science.gov (United States)

    Hido, Margarita; Shehu, Irena

    2010-01-01

    In the Albanian schools settings does not exist religious discrimination, neither gender discrimination, but there exists a discrimination, as unfair against children called "difficulty". The children who drop out of school are by far less numerous compared with those who start school, but who are not properly treated, so that they can…

  5. DYSPNEA ASSOCIATED WITH ANXIETY: MISTAKES AND DIFFICULTIES IN THE DIAGNOSIS

    Directory of Open Access Journals (Sweden)

    L. I. Tyukalova

    2013-01-01

    Full Text Available Two clinical cases that demonstrate the difficulties diagnosing the causes of shortness of breath, coupled with anxiety, are analyzed. From the standpoint of modern neurophysiology it explains the relationship of these conditions. There were revealed typical diagnostic mistakes: «the effect of precocious focusing", "the negative effect of the narrow specialization

  6. Eye Movements Reveal How Task Difficulty Moulds Visual Search

    Science.gov (United States)

    Young, Angela H.; Hulleman, Johan

    2013-01-01

    In two experiments we investigated the relationship between eye movements and performance in visual search tasks of varying difficulty. Experiment 1 provided evidence that a single process is used for search among static and moving items. Moreover, we estimated the functional visual field (FVF) from the gaze coordinates and found that its size…

  7. Common difficulties experienced by grade 12 students in learning ...

    African Journals Online (AJOL)

    The objective of this study was to examine the nature and causes of common difficulties experienced by grade twelve students in learning chemistry in Ebinat preparatory school. A qualitative method was employed to investigate the questions, which used interviews and questionnaires with students and teachers. The key ...

  8. Student Difficulties Regarding Symbolic and Graphical Representations of Vector Fields

    Science.gov (United States)

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

    2017-01-01

    The ability to switch between various representations is an invaluable problem-solving skill in physics. In addition, research has shown that using multiple representations can greatly enhance a person's understanding of mathematical and physical concepts. This paper describes a study of student difficulties regarding interpreting, constructing,…

  9. Brain Regions Underlying Word Finding Difficulties in Temporal Lobe Epilepsy

    Science.gov (United States)

    Trebuchon-Da Fonseca, Agnes; Guedj, Eric; Alario, F-Xavier; Laguitton, Virginie; Mundler, Olivier; Chauvel, Patrick; Liegeois-Chauvel, Catherine

    2009-01-01

    Word finding difficulties are often reported by epileptic patients with seizures originating from the language dominant cerebral hemisphere, for example, in temporal lobe epilepsy. Evidence regarding the brain regions underlying this deficit comes from studies of peri-operative electro-cortical stimulation, as well as post-surgical performance.…

  10. Are Difficulties Balancing Work and Family Associated with Subsequent Fertility?

    Science.gov (United States)

    Liu, Siwei; Hynes, Kathryn

    2012-01-01

    Despite considerable interest in the causes and consequences of work-family conflict, and the frequent suggestion in fertility research that difficulty in balancing work and family is one of the factors leading to low fertility rates in several developed countries, little research uses longitudinal data to examine whether women who report…

  11. Difficulties on the road to a liberalized energy market

    International Nuclear Information System (INIS)

    Koevoet, H.

    2001-01-01

    Starting January 1, 2002 about 55,000 consumers of electricity and 2,100 consumers of natural gas (small and medium-sized businesses) in the Netherlands can choose their own supplier. Some of the constraints and difficulties with respect to the liberalized energy market in the Netherlands are discussed

  12. Interdisciplinary collaboration and conflict about inclusion and children in difficulties

    DEFF Research Database (Denmark)

    Røn Larsen, Maja

    My paper builds on the “sub-project C” concerned with: Legislation and administration as institutional conditions for interdisciplinary collaboration about children in difficulties in school. I have been doing the research together within, Stine Jørgensen, who is a researcher at the faculty of law...

  13. Addressing the Difficulties of Learners in the Reading Class ...

    African Journals Online (AJOL)

    This study evaluates reading comprehension instruction at senior high schools in Accra. Classroom observation was used to identify the techniques used by teachers in the reading class and questionnaire was used to collect information from learners about the difficulties they have in understanding text. It reports that the ...

  14. Preoperative ultrasonography and prediction of technical difficulties during laparoscopic cholecystectomy.

    Science.gov (United States)

    Daradkeh, S S; Suwan, Z; Abu-Khalaf, M

    1998-01-01

    A prospective study was carried out to investigate the value of preoperative ultrasound findings for predicting difficulties encountered during laparoscopic cholecystectomy (LC). Altogether 160 consecutive patients with symptomatic gallbladder (GB) disease (130 females, 30 males) referred to the Jordan University Hospital were recruited for the purpose of this study. All patients underwent detailed ultrasound examination 24 hours prior to LC. The overall difficulty score (ODS), as a dependent variable, was based on the following operative parameters: duration of surgery, bleeding, dissection of Calot's triangle, dissection of gallbladder wall, adhesions, spillage of bile, spillage of stone, and difficulty of gallbladder extraction. Multiple regression analysis was used to assess the significance of the following preoperative ultrasound variables (independent) for predicting the variation in the ODS: size of the GB, number of GB stones, size of stones, location of GB stones, thickness of GB wall, common bile duct (CBD) diameter, and liver size. Only thickness of GB wall and CBD diameter were found to be significant predictors of the variation in the ODS (adjusted R2 = 0.25). We conclude that the preoperative ultrasound examination is of value for predicting difficulties encountered during LC, but it is not the sole predictor.

  15. Financial difficulties lead OPEC countries on the prices correction way

    International Nuclear Information System (INIS)

    Anon.

    1994-01-01

    The financial difficulties of OPEC countries are going to lead them to correct the petroleum prices. In front of a decreasing since 1992, it is necessary to make them grow of about $1 the barrel. It is the principal conclusion of Bali meeting for next months even perhaps for next years

  16. Sleep Difficulties and Academic Performance in Norwegian Higher Education Students

    Science.gov (United States)

    Hayley, Amie C.; Sivertsen, Børge; Hysing, Mari; Vedaa, Øystein; Øverland, Simon

    2017-01-01

    Background: Sleep difficulties are common among university students and may detrimentally affect academic outcomes. Despite this, remarkably little information is currently available during this critical developmental period of early adulthood, and thus, the direct effect on measurable domains of academic ability and proficiency is equivocal.…

  17. Sleep difficulties and academic performance in Norwegian higher education students.

    Science.gov (United States)

    Hayley, Amie C; Sivertsen, Børge; Hysing, Mari; Vedaa, Øystein; Øverland, Simon

    2017-12-01

    Sleep difficulties are common among university students and may detrimentally affect academic outcomes. Despite this, remarkably little information is currently available during this critical developmental period of early adulthood, and thus, the direct effect on measurable domains of academic ability and proficiency is equivocal. To evaluate the associations between difficulties initiating and maintaining sleep (DIMS) and subjective and objective academic performance in a large sample of university students. A total of 12,915 students who participated in large student survey in Norway from 24 February 2014 to 27 March 2014. DIMS was assessed by the Hopkins Symptoms Checklist (HSCL-25), and academic outcomes included failed examinations, delayed study progress, and school-related self-efficacy (General Self-Efficacy Scale). Difficulties initiating and maintaining sleep was independently associated with increased odds for poor school performance for all academic outcomes. Reporting 'extreme' DIMS was associated with increased odds of reporting delayed study progress (adjusted odds ratio [OR] = 1.25, 95% CI 1.01-1.57, p academic outcomes as well as poorer self-rated academic proficiency among higher education students. Amelioration of sleep difficulties may improve overall academic performance and health outcomes in affected students. © 2017 The British Psychological Society.

  18. Tracking Change in Children with Severe and Persisting Speech Difficulties

    Science.gov (United States)

    Newbold, Elisabeth Joy; Stackhouse, Joy; Wells, Bill

    2013-01-01

    Standardised tests of whole-word accuracy are popular in the speech pathology and developmental psychology literature as measures of children's speech performance. However, they may not be sensitive enough to measure changes in speech output in children with severe and persisting speech difficulties (SPSD). To identify the best ways of doing this,…

  19. Handwriting difficulties in juvenile idiopathic arthritis: a pilot study

    NARCIS (Netherlands)

    Haberfehlner, Helga; Visser, Bart; Daffertshofer, Andreas; van Rossum, Marion Aj; Roorda, Leo D.; van der Leeden, Marike; Dekker, Joost; Hoeksma, Agnes F.

    2011-01-01

    The aim of the present study was to describe handwriting difficulties of primary school children with juvenile idiopathic arthritis (JIA), and to investigate possible correlations with hand function and writing performance. In a cross-sectional approach, 15 children with JIA and reported handwriting

  20. Career Decision-Making Difficulties of Turkish Adolescents

    Science.gov (United States)

    Bacanli, Feride

    2016-01-01

    The purposes of this study are (1) to adapt the Career Decision-Making Difficulties Questionnaire (CDDQ) to Turkish high school students and (2) to examine gender differences, grade differences, and differences between "decided" and "undecided" students. The sample consisted of 2509 adolescent students. The results showed that…

  1. Fast and Efficient Discrimination of Traveling Salesperson Problem Stimulus Difficulty

    Science.gov (United States)

    Dry, Matthew J.; Fontaine, Elizabeth L.

    2014-01-01

    The Traveling Salesperson Problem (TSP) is a computationally difficult combinatorial optimization problem. In spite of its relative difficulty, human solvers are able to generate close-to-optimal solutions in a close-to-linear time frame, and it has been suggested that this is due to the visual system's inherent sensitivity to certain geometric…

  2. Using Student Performance to Judge the Difficulty of Examinations

    Science.gov (United States)

    Roegner, Katherine

    2015-01-01

    This contribution focuses on a scheme developed to characterize the level of difficulty of an examination in the course "Linear Algebra for Engineers" and on the transfer of the underlying idea to a similar scheme for examinations in the course "Analysis I for Engineers". Using these schemes, it is possible to define standards…

  3. Difficulties in Learning and Teaching Statistics: Teacher Views

    Science.gov (United States)

    Koparan, Timur

    2015-01-01

    The purpose of this study is to define teacher views about the difficulties in learning and teaching middle school statistics subjects. To serve this aim, a number of interviews were conducted with 10 middle school maths teachers in 2011-2012 school year in the province of Trabzon. Of the qualitative descriptive research methods, the…

  4. Specific Learning Difficulties--What Teachers Need to Know

    Science.gov (United States)

    Hudson, Diana

    2015-01-01

    This book clearly explains what Specific Learning Difficulties (SpLD) are, and describes the symptoms of conditions most commonly encountered in the mainstream classroom: dyslexia, dyspraxia, dyscalculia, dysgraphia, Autism Spectrum Disorder, ADHD, and OCD. The author provides an overview of the strengths and weaknesses commonly associated with…

  5. Investigating Difficulties of Learning Computer Programming in Saudi Arabia

    Science.gov (United States)

    Alakeel, Ali M.

    2015-01-01

    Learning computer programming is one of the main requirements of many educational study plans in higher education. Research has shown that many students face difficulties acquiring reasonable programming skills during their first year of college. In Saudi Arabia, there are twenty-three state-owned universities scattered around the country that…

  6. Could Specific Braille Reading Difficulties Result from Developmental Dyslexia?

    Science.gov (United States)

    Veispak, Anneli; Ghesquiere, Pol

    2010-01-01

    A proportion of children with visual impairments have specific reading difficulties that cannot be easily explained. This article reviews the data on problems with braille reading and interprets them from the framework of the temporal-processing deficit theory of developmental dyslexia.

  7. DIFFICULTIES TO LEARN AND TO TEACH MODERN PHYSICS.

    Directory of Open Access Journals (Sweden)

    R. Antonowiski

    2017-08-01

    Full Text Available Physics is engaged in scientific and technological development in several areas, however, its learning in high school has high failure rates that demonstrate a low level of use. It is a science that allows us to understand the nature of the macroscopic and atomic matter, but it is taught in a disjointed manner, upon presentation of concepts, laws and mathematical sentences, repetitive exercises that have taken the preparatory character for college entrance. Thus, the student gets stuck sentences featuring a partial knowledge and disposable. This study aimed to analyze the main difficulties that undergraduate students in Physics have in Modern Physics learning. Point out the difficulties in teaching and learning Physics is not an easy task and to identify them comes the difficulty of how to solve them. After analysis of several hypotheses we can conclude that there is no single factor responsible for the difficulty of the teaching and learning of Modern Physics. The lack of time to work and developed since middle school, stimulating the curiosity of students, adequately trained teachers, lack of structure offered by the government, parents' responsibilities and students in learning, among others, constitute a major challenge for successful teaching and learning of Modern Physics

  8. The Implementation of APIQ Creative Mathematics Game Method in the Subject Matter of Greatest Common Factor and Least Common Multiple in Elementary School

    Science.gov (United States)

    Rahman, Abdul; Saleh Ahmar, Ansari; Arifin, A. Nurani M.; Upu, Hamzah; Mulbar, Usman; Alimuddin; Arsyad, Nurdin; Ruslan; Rusli; Djadir; Sutamrin; Hamda; Minggi, Ilham; Awi; Zaki, Ahmad; Ahmad, Asdar; Ihsan, Hisyam

    2018-01-01

    One of causal factors for uninterested feeling of the students in learning mathematics is a monotonous learning method, like in traditional learning method. One of the ways for motivating students to learn mathematics is by implementing APIQ (Aritmetika Plus Intelegensi Quantum) creative mathematics game method. The purposes of this research are (1) to describe students’ responses toward the implementation of APIQ creative mathematics game method on the subject matter of Greatest Common Factor (GCF) and Least Common Multiple (LCM) and (2) to find out whether by implementing this method, the student’s learning completeness will improve or not. Based on the results of this research, it is shown that the responses of the students toward the implementation of APIQ creative mathematics game method in the subject matters of GCF and LCM were good. It is seen in the percentage of the responses were between 76-100%. (2) The implementation of APIQ creative mathematics game method on the subject matters of GCF and LCM improved the students’ learning.

  9. MODEL PEMBELAJARAN PROBLEM POSING DENGAN PENDEKATAN SAINTIFIK UNTUK MENINGKATKAN KEMAMPUAN PEMECAHAN MASALAH

    Directory of Open Access Journals (Sweden)

    Adi Purnomo

    2015-08-01

    Full Text Available Tujuan penelitian ini untuk menghasilkan perangkat pembelajaran model problem posing pendekatan saintifik yang valid, praktis dan efektif. Penelitian ini merupakan penelitian pengembangan dengan model Thiagarajan. Pengolahan data penelitian untuk uji kevalidan dan kepraktisan dilakukan dengan menghitung rata-rata skor, sedangkan uji keefektifan dilakukan dengan uji t, uji proporsi, uji regresi, uji t berpasangan, dan uji normalitas gain. Hasil pengembangan diperoleh perangkat pembelajaran dinyatakan valid dengan rata-rata skor validasi silabus 4,3, RPP 4,31, buku peserta didik 4,24, LKPD 4,16, TKPM 4,19, dari skor maksimal 5,00. Perangkat pembelajaran praktis berdasarkan hasil pengamatan kemampuan guru 4,5 (sangat baik dan respon peserta didik 3,8 (baik. Implementasi perangkat pembelajaran efektif yang ditunjukkan dengan: (1 ketuntasan klasikal TKKM melampaui 75%, rata-rata kelas melampaui KKM; (2 kemampuan pemecahan masalah peserta didik yang pembelajarannya menggunakan model problrm posing pendekatan saintifik lebih baik dari pada peserta didik dengan pembelajaran konvensional; (3 keterampilan proses saintifik dan karakter kemandirian berpengaruh positif terhadap kemampuan pemecahan masalah; dan (4 adanya peningkatan pemecahan masalah dan mendiskripsikan peningkatan kemampuan pemecahan masalah berdasarkan Taksonomi SOLO.The purpose of this research to development lesson plan through problem posing model with scientific approach which are valid, practical, and effective. The development research using Thiagarajan model. Processing data for validation and practice can be done calculating the score average, while effectivity by use of t-test, proportion test, regression test, paired t-test, n-gain. The lesson plan is valid based on the average of validation scores syllabus 4,3, RPP 4,31, student book 4,24, LKPD 4,16, TKPM 4,19.  The lesson plan is practical based on the result of observation teacher ability 4,53 and student response 4,23. The

  10. Problems which are well posed in a generalized sense with applications to the Einstein equations

    International Nuclear Information System (INIS)

    Kreiss, H-O; Winicour, J

    2006-01-01

    In the harmonic description of general relativity, the principal part of the Einstein equations reduces to a constrained system of ten curved space wave equations for the components of the spacetime metric. We use the pseudo- differential theory of systems which are strongly well posed in the generalized sense to establish the well posedness of constraint-preserving boundary conditions for this system when treated in a second-order differential form. The boundary conditions are of a generalized Sommerfeld type that is benevolent for numerical calculation

  11. Iterative Runge–Kutta-type methods for nonlinear ill-posed problems

    International Nuclear Information System (INIS)

    Böckmann, C; Pornsawad, P

    2008-01-01

    We present a regularization method for solving nonlinear ill-posed problems by applying the family of Runge–Kutta methods to an initial value problem, in particular, to the asymptotical regularization method. We prove that the developed iterative regularization method converges to a solution under certain conditions and with a general stopping rule. Some particular iterative regularization methods are numerically implemented. Numerical results of the examples show that the developed Runge–Kutta-type regularization methods yield stable solutions and that particular implicit methods are very efficient in saving iteration steps

  12. Regularization parameter selection methods for ill-posed Poisson maximum likelihood estimation

    International Nuclear Information System (INIS)

    Bardsley, Johnathan M; Goldes, John

    2009-01-01

    In image processing applications, image intensity is often measured via the counting of incident photons emitted by the object of interest. In such cases, image data noise is accurately modeled by a Poisson distribution. This motivates the use of Poisson maximum likelihood estimation for image reconstruction. However, when the underlying model equation is ill-posed, regularization is needed. Regularized Poisson likelihood estimation has been studied extensively by the authors, though a problem of high importance remains: the choice of the regularization parameter. We will present three statistically motivated methods for choosing the regularization parameter, and numerical examples will be presented to illustrate their effectiveness

  13. Problems posed by the development of the Oklo phenomenon: tentative global interpretation

    International Nuclear Information System (INIS)

    Naudet, R.

    This paper discusses the basic problems posed by the development of the Oklo phenomenon: the conditions in which the reactions are triggered and propagated and how they have been controlled. The reactions were maintained by the destruction of neutron poisons in the ore and were controlled by temperature. Oklo is made up of a large number of contiguous reactors. Geological problems of the origin of the clays, desilification, and uranium concentration are discussed. Oklo is shown to be a very complex phenomenon which developed in space and time. Besides the thermal, neutron, and geochemical coupling, there is also a tectonic coupling

  14. Minimization of Linear Functionals Defined on| Solutions of Large-Scale Discrete Ill-Posed Problems

    DEFF Research Database (Denmark)

    Elden, Lars; Hansen, Per Christian; Rojas, Marielba

    2003-01-01

    The minimization of linear functionals de ned on the solutions of discrete ill-posed problems arises, e.g., in the computation of con dence intervals for these solutions. In 1990, Elden proposed an algorithm for this minimization problem based on a parametric-programming reformulation involving...... the solution of a sequence of trust-region problems, and using matrix factorizations. In this paper, we describe MLFIP, a large-scale version of this algorithm where a limited-memory trust-region solver is used on the subproblems. We illustrate the use of our algorithm in connection with an inverse heat...

  15. Dr. David Brown poses with students at Ronald McNair Middle School

    Science.gov (United States)

    1999-01-01

    Dr. David Brown (right), a NASA astronaut, poses with students in the gymnasium of Ronald McNair Magnet School in Cocoa, Fla. From left, the students are Kristin Rexford, Danitra Anderson, Dominique Smith, Fallon Davis, and Qiana Taylor. Brown was at the school to attend a tribute to NASA astronaut Ronald McNair. The school had previously been renamed for the fallen astronaut who was one of a crew of seven, who lost their lives during an accident following launch of the Space Shuttle Challenger in January 1986.

  16. Ms. Rodriquez and Mickey Mouse pose with a portrait of Ronald McNair

    Science.gov (United States)

    1999-01-01

    In the gymnasium of Ronald McNair Magnet School in Cocoa, Fla., Ms. Maria Rodriguez, an Walt Disney World Ambassador, and Mickey Mouse pose with a portrait of NASA astronaut Ronald McNair. The portrait was presented to the school by Walt Disney World during a tribute to McNair. The school had previously been renamed for the fallen astronaut, who was one of a crew of seven who lost their lives during an accident following launch of the Space Shuttle Challenger in January 1986.

  17. Extended 3D Line Segments from RGB-D Data for Pose Estimation

    DEFF Research Database (Denmark)

    Buch, Anders Glent; Jessen, Jeppe Barsøe; Kraft, Dirk

    2013-01-01

    We propose a method for the extraction of complete and rich symbolic line segments in 3D based on RGB-D data. Edges are detected by combining cues from the RGB image and the aligned depth map. 3D line segments are then reconstructed by back-projecting 2D line segments and intersecting this with l...... this with local surface patches computed from the 3D point cloud. Different edge types are classified using the new enriched representation and the potential of this representation for the task of pose estimation is demonstrated....

  18. Identifying predictors of physics item difficulty: A linear regression approach

    Science.gov (United States)

    Mesic, Vanes; Muratovic, Hasnija

    2011-06-01

    Large-scale assessments of student achievement in physics are often approached with an intention to discriminate students based on the attained level of their physics competencies. Therefore, for purposes of test design, it is important that items display an acceptable discriminatory behavior. To that end, it is recommended to avoid extraordinary difficult and very easy items. Knowing the factors that influence physics item difficulty makes it possible to model the item difficulty even before the first pilot study is conducted. Thus, by identifying predictors of physics item difficulty, we can improve the test-design process. Furthermore, we get additional qualitative feedback regarding the basic aspects of student cognitive achievement in physics that are directly responsible for the obtained, quantitative test results. In this study, we conducted a secondary analysis of data that came from two large-scale assessments of student physics achievement at the end of compulsory education in Bosnia and Herzegovina. Foremost, we explored the concept of “physics competence” and performed a content analysis of 123 physics items that were included within the above-mentioned assessments. Thereafter, an item database was created. Items were described by variables which reflect some basic cognitive aspects of physics competence. For each of the assessments, Rasch item difficulties were calculated in separate analyses. In order to make the item difficulties from different assessments comparable, a virtual test equating procedure had to be implemented. Finally, a regression model of physics item difficulty was created. It has been shown that 61.2% of item difficulty variance can be explained by factors which reflect the automaticity, complexity, and modality of the knowledge structure that is relevant for generating the most probable correct solution, as well as by the divergence of required thinking and interference effects between intuitive and formal physics knowledge

  19. Identifying predictors of physics item difficulty: A linear regression approach

    Directory of Open Access Journals (Sweden)

    Hasnija Muratovic

    2011-06-01

    Full Text Available Large-scale assessments of student achievement in physics are often approached with an intention to discriminate students based on the attained level of their physics competencies. Therefore, for purposes of test design, it is important that items display an acceptable discriminatory behavior. To that end, it is recommended to avoid extraordinary difficult and very easy items. Knowing the factors that influence physics item difficulty makes it possible to model the item difficulty even before the first pilot study is conducted. Thus, by identifying predictors of physics item difficulty, we can improve the test-design process. Furthermore, we get additional qualitative feedback regarding the basic aspects of student cognitive achievement in physics that are directly responsible for the obtained, quantitative test results. In this study, we conducted a secondary analysis of data that came from two large-scale assessments of student physics achievement at the end of compulsory education in Bosnia and Herzegovina. Foremost, we explored the concept of “physics competence” and performed a content analysis of 123 physics items that were included within the above-mentioned assessments. Thereafter, an item database was created. Items were described by variables which reflect some basic cognitive aspects of physics competence. For each of the assessments, Rasch item difficulties were calculated in separate analyses. In order to make the item difficulties from different assessments comparable, a virtual test equating procedure had to be implemented. Finally, a regression model of physics item difficulty was created. It has been shown that 61.2% of item difficulty variance can be explained by factors which reflect the automaticity, complexity, and modality of the knowledge structure that is relevant for generating the most probable correct solution, as well as by the divergence of required thinking and interference effects between intuitive and formal

  20. A randomized controlled study of power posing before public speaking exposure for social anxiety disorder: No evidence for augmentative effects.

    Science.gov (United States)

    Davis, Michelle L; Papini, Santiago; Rosenfield, David; Roelofs, Karin; Kolb, Sarah; Powers, Mark B; Smits, Jasper A J

    2017-12-01

    This manuscript details a randomized controlled study designed to test the efficacy of power posing (i.e., briefly holding postures associated with dominance and power) as an augmentative strategy for exposure therapy for social anxiety disorder (SAD). Seventy-three individuals diagnosed with SAD were assigned to one of three conditions: power posing, submissive posing, or rest (no posing) prior to participating in an exposure therapy session. Participants were assessed for between-group differences in pre- and post-manipulation salivary hormone levels, within-session subjective experiences of fear, and pre- and 1-week post-treatment SAD severity outcome measures. Though the intervention resulted in decreased SAD symptom severity one week later, analyses revealed no significant between-group differences on any tested variables. Accordingly, this study provides no evidence to suggest that power posing impacts hormone levels or exposure therapy outcomes. Copyright © 2017 Elsevier Ltd. All rights reserved.