Student Conceptions about Energy Transformations: Progression from General Chemistry to Biochemistry

Science.gov (United States)

Wolfson, Adele J.; Rowland, Susan L.; Lawrie, Gwendolyn A.; Wright, Anthony H.

2014-01-01

Students commencing studies in biochemistry must transfer and build on concepts they learned in chemistry and biology classes. It is well established, however, that students have difficulties in transferring critical concepts from general chemistry courses; one key concept is "energy." Most previous work on students' conception of energy…

Victories and defeats in general relativity theory

International Nuclear Information System (INIS)

Moeller, C.

1977-01-01

Only within the last 20 years has it been possible to conduct far-reaching experimental tests of the validity of Einstein's General Relativity Theory. Experimental confirmation in some fields is embarrassed by considerable difficulties in applying the theory to cosmic systems, which indicate that such major systems lie at the limit of the theory's applicability. The lecture here reproduced discusses both the successes and the limitations of the theory, starting with its replacement of the absolute space-time theory of Newton and its historical replacement by the relativistic gravitational postulates of Einstein which, in spite of its more complicated postulates, nevertheless introduced a great simplicity and comprehensiveness into the overall conception of nature. This theoretical 'beauty', however, can only be trusted if vindicated experimentally, which has to a considerable extent proved to be the case. For weak fields Newtonian and Einsteinian concepts coincide, while for stronger fields, and velocities not far from that of light, Einstein's theory is superior, giving,for example, an excellent correspondence with the precession of the perehelion of Mercury. On a larger scale, however, the theory appears to lead to conclusions which would invalidate the very concepts of space and time, even within a finite time-interval. A more generalized theory seems to be required. (A.D.N.)

The Nature of Living Systems: An Exposition of the Basic Concepts in General Systems Theory.

Science.gov (United States)

Miller, James G.

General systems theory is a set of related definitions, assumptions, and propositions which deal with reality as an integrated hierarchy of organizations of matter and energy. In this paper, the author defines the concepts of space, time, matter, energy, and information in terms of their meaning in general systems theory. He defines a system as a…

The Electromagnetic Conception of Nature at the Root of the Special and General Relativity Theories and Its Revolutionary Meaning

Science.gov (United States)

Giannetto, Enrico R. A.

2009-01-01

The revolution in XX century physics, induced by relativity theories, had its roots within the electromagnetic conception of Nature. It was developed through a tradition related to Brunian and Leibnizian physics, to the German "Naturphilosophie" and English XIXth physics. The electromagnetic conception of Nature was in some way realized by the…

Relativity Concept Inventory: Development, Analysis, and Results

Science.gov (United States)

Aslanides, J. S.; Savage, C. M.

2013-01-01

We report on a concept inventory for special relativity: the development process, data analysis methods, and results from an introductory relativity class. The Relativity Concept Inventory tests understanding of relativistic concepts. An unusual feature is confidence testing for each question. This can provide additional information; for example,…

Einstein's space-time an introduction to special and general relativity

CERN Document Server

Ferraro, Rafael

2007-01-01

Einstein's Space-Time: An Introduction to Special and General Relativity is a textbook addressed to students in physics and other people interested in Relativity and a history of physics. The book contains a complete account of Special Relativity that begins with the historical analysis of the reasons that led to a change in our manner of regarding the space and time. The first chapters are aimed to afford a deep understanding of the relativistic spacetime and its consequences for Dynamics. The chapter about covariant formulation includes among its topics the concepts of volume and hypersurfaces in manifolds, energy-momentum tensor of a fluid, and prepares the language for General Relativity. The last two chapters are devoted to an introduction of General Relativity and Cosmology in a modern approach connected with the latest discoveries in these areas.

Parallel Evolution in Science: The Historical Roots and Central Concepts of General Systems Theory; and "General Systems Theory,""Modern Organizational Theory," and Organizational Communication.

Science.gov (United States)

Lederman, Linda Costigan; Rogers, Don

The two papers in this document focus on general systems theory. In her paper, Linda Lederman discusses the emergence and evolution of general systems theory, defines its central concepts, and draws some conclusions regarding the nature of the theory and its value as an epistemology. Don Rogers, in his paper, relates some of the important features…

General Business Model Patterns for Local Energy Management Concepts

International Nuclear Information System (INIS)

Facchinetti, Emanuele; Sulzer, Sabine

2016-01-01

The transition toward a more sustainable global energy system, significantly relying on renewable energies and decentralized energy systems, requires a deep reorganization of the energy sector. The way how energy services are generated, delivered, and traded is expected to be very different in the coming years. Business model innovation is recognized as a key driver for the successful implementation of the energy turnaround. This work contributes to this topic by introducing a heuristic methodology easing the identification of general business model patterns best suited for Local Energy Management concepts such as Energy Hubs. A conceptual framework characterizing the Local Energy Management business model solution space is developed. Three reference business model patterns providing orientation across the defined solution space are identified, analyzed, and compared. Through a market review, a number of successfully implemented innovative business models have been analyzed and allocated within the defined solution space. The outcomes of this work offer to potential stakeholders a starting point and guidelines for the business model innovation process, as well as insights for policy makers on challenges and opportunities related to Local Energy Management concepts.

General Business Model Patterns for Local Energy Management Concepts

Energy Technology Data Exchange (ETDEWEB)

Facchinetti, Emanuele, E-mail: emanuele.facchinetti@hslu.ch; Sulzer, Sabine [Lucerne Competence Center for Energy Research, Lucerne University of Applied Science and Arts, Horw (Switzerland)

2016-03-03

The transition toward a more sustainable global energy system, significantly relying on renewable energies and decentralized energy systems, requires a deep reorganization of the energy sector. The way how energy services are generated, delivered, and traded is expected to be very different in the coming years. Business model innovation is recognized as a key driver for the successful implementation of the energy turnaround. This work contributes to this topic by introducing a heuristic methodology easing the identification of general business model patterns best suited for Local Energy Management concepts such as Energy Hubs. A conceptual framework characterizing the Local Energy Management business model solution space is developed. Three reference business model patterns providing orientation across the defined solution space are identified, analyzed, and compared. Through a market review, a number of successfully implemented innovative business models have been analyzed and allocated within the defined solution space. The outcomes of this work offer to potential stakeholders a starting point and guidelines for the business model innovation process, as well as insights for policy makers on challenges and opportunities related to Local Energy Management concepts.

Abstract memory representations in the ventromedial prefrontal cortex and hippocampus support concept generalization.

Science.gov (United States)

Bowman, Caitlin R; Zeithamova, Dagmar

2018-02-07

Memory function involves both the ability to remember details of individual experiences and the ability to link information across events to create new knowledge. Prior research has identified the ventromedial prefrontal cortex (VMPFC) and the hippocampus as important for integrating across events in service of generalization in episodic memory. The degree to which these memory integration mechanisms contribute to other forms of generalization, such as concept learning, is unclear. The present study used a concept-learning task in humans (both sexes) coupled with model-based fMRI to test whether VMPFC and hippocampus contribute to concept generalization, and whether they do so by maintaining specific category exemplars or abstract category representations. Two formal categorization models were fit to individual subject data: a prototype model that posits abstract category representations and an exemplar model that posits category representations based on individual category members. Latent variables from each of these models were entered into neuroimaging analyses to determine whether VMPFC and the hippocampus track prototype or exemplar information during concept generalization. Behavioral model fits indicated that almost three quarters of the subjects relied on prototype information when making judgments about new category members. Paralleling prototype dominance in behavior, correlates of the prototype model were identified in VMPFC and the anterior hippocampus with no significant exemplar correlates. These results indicate that the VMPFC and portions of the hippocampus play a broad role in memory generalization and that they do so by representing abstract information integrated from multiple events. SIGNIFICANCE STATEMENT Whether people represent concepts as a set of individual category members or by deriving generalized concept representations abstracted across exemplars has been debated. In episodic memory, generalized memory representations have been shown

Longitudinal Relation Between General Well-Being and Self-Esteem.

Science.gov (United States)

Barendregt, Charlotte S; van der Laan, André M; Bongers, Ilja L; van Nieuwenhuizen, Chijs

2016-12-01

This study investigated the longitudinal relation between general well-being and self-esteem of male adolescents with severe psychiatric disorders. Moreover, the transition out of secure residential care was studied. Adolescents ( N = 172) were assessed three times with 6 months between each assessment. The sample comprised adolescents who were admitted throughout the entire study ( n = 116) and who had been discharged at 6/12 months follow-up ( n = 56). General well-being and self-esteem were stable concepts over time. The relation between general well-being and self-esteem differed for both groups. Among the admitted group general well-being positively predicted self-esteem and self-esteem negatively predicted general well-being from Time 2 to Time 3. Among the discharged adolescents, self-esteem at Time 1 positively predicted general well-being at Time 2 and general well-being at Time 2 positively predicted self-esteem at Time 3. Changing social contexts, as well as problems experienced during the transition out of secure care, might affect this relationship.

Artificial General Intelligence: Concept, State of the Art, and Future Prospects

Science.gov (United States)

Goertzel, Ben

2014-12-01

In recent years broad community of researchers has emerged, focusing on the original ambitious goals of the AI field - the creation and study of software or hardware systems with general intelligence comparable to, and ultimately perhaps greater than, that of human beings. This paper surveys this diverse community and its progress. Approaches to defining the concept of Artificial General Intelligence (AGI) are reviewed including mathematical formalisms, engineering, and biology inspired perspectives. The spectrum of designs for AGI systems includes systems with symbolic, emergentist, hybrid and universalist characteristics. Metrics for general intelligence are evaluated, with a conclusion that, although metrics for assessing the achievement of human-level AGI may be relatively straightforward (e.g. the Turing Test, or a robot that can graduate from elementary school or university), metrics for assessing partial progress remain more controversial and problematic.

General Relativity

CERN Document Server

Straumann, Norbert

2013-01-01

This book provides a completely revised and expanded version of the previous classic edition ‘General Relativity and Relativistic Astrophysics’. In Part I the foundations of general relativity are thoroughly developed, while Part II is devoted to tests of general relativity and many of its applications. Binary pulsars – our best laboratories for general relativity – are studied in considerable detail. An introduction to gravitational lensing theory is included as well, so as to make the current literature on the subject accessible to readers. Considerable attention is devoted to the study of compact objects, especially to black holes. This includes a detailed derivation of the Kerr solution, Israel’s proof of his uniqueness theorem, and a derivation of the basic laws of black hole physics. Part II ends with Witten’s proof of the positive energy theorem, which is presented in detail, together with the required tools on spin structures and spinor analysis. In Part III, all of the differential geomet...

Canonical perturbation theory in linearized general relativity theory

International Nuclear Information System (INIS)

Gonzales, R.; Pavlenko, Yu.G.

1986-01-01

Canonical perturbation theory in linearized general relativity theory is developed. It is shown that the evolution of arbitrary dynamic value, conditioned by the interaction of particles, gravitation and electromagnetic fields, can be presented in the form of a series, each member of it corresponding to the contribution of certain spontaneous or induced process. The main concepts of the approach are presented in the approximation of a weak gravitational field

Green economy and related concepts

NARCIS (Netherlands)

Loiseau, Eleonore; Saikku, Laura; Antikainen, Riina; Droste, Nils; Hansjürgens, Bernd; Pitkänen, Kati; Leskinen, Pekka; Kuikman, Peter; Thomsen, Marianne

2016-01-01

For the last ten years, the notion of a green economy has become increasingly attractive to policy makers. However, green economy covers a lot of diverse concepts and its links with sustainability are not always clear. In this article, we focus on definitions of green economy and related concepts

Auditing the multiply-related concepts within the UMLS.

Science.gov (United States)

Mougin, Fleur; Grabar, Natalia

2014-10-01

This work focuses on multiply-related Unified Medical Language System (UMLS) concepts, that is, concepts associated through multiple relations. The relations involved in such situations are audited to determine whether they are provided by source vocabularies or result from the integration of these vocabularies within the UMLS. We study the compatibility of the multiple relations which associate the concepts under investigation and try to explain the reason why they co-occur. Towards this end, we analyze the relations both at the concept and term levels. In addition, we randomly select 288 concepts associated through contradictory relations and manually analyze them. At the UMLS scale, only 0.7% of combinations of relations are contradictory, while homogeneous combinations are observed in one-third of situations. At the scale of source vocabularies, one-third do not contain more than one relation between the concepts under investigation. Among the remaining source vocabularies, seven of them mainly present multiple non-homogeneous relations between terms. Analysis at the term level also shows that only in a quarter of cases are the source vocabularies responsible for the presence of multiply-related concepts in the UMLS. These results are available at: http://www.isped.u-bordeaux2.fr/ArticleJAMIA/results_multiply_related_concepts.aspx. Manual analysis was useful to explain the conceptualization difference in relations between terms across source vocabularies. The exploitation of source relations was helpful for understanding why some source vocabularies describe multiple relations between a given pair of terms. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Relativity concept inventory: Development, analysis, and results

Directory of Open Access Journals (Sweden)

J. S. Aslanides

2013-05-01

Full Text Available We report on a concept inventory for special relativity: the development process, data analysis methods, and results from an introductory relativity class. The Relativity Concept Inventory tests understanding of relativistic concepts. An unusual feature is confidence testing for each question. This can provide additional information; for example, high confidence correlated with incorrect answers suggests a misconception. A novel aspect of our data analysis is the use of Monte Carlo simulations to determine the significance of correlations. This approach is particularly useful for small sample sizes, such as ours. Our results show a gender bias that was not present in course assessment, similar to that reported for the Force Concept Inventory.

BOOK REVIEW: Advanced Mechanics and General Relativity Advanced Mechanics and General Relativity

Science.gov (United States)

Louko, Jorma

2011-04-01

Joel Franklin's textbook `Advanced Mechanics and General Relativity' comprises two partially overlapping, partially complementary introductory paths into general relativity at advanced undergraduate level. Path I starts with the Lagrangian and Hamiltonian formulations of Newtonian point particle motion, emphasising the action principle and the connection between symmetries and conservation laws. The concepts are then adapted to point particle motion in Minkowski space, introducing Lorentz transformations as symmetries of the action. There follows a focused development of tensor calculus, parallel transport and curvature, using examples from Newtonian mechanics and special relativity, culminating in the field equations of general relativity. The Schwarzschild solution is analysed, including a detailed discussion of the tidal forces on a radially infalling observer. Basics of gravitational radiation are examined, highlighting the similarities to and differences from electromagnetic radiation. The final topics in Path I are equatorial geodesics in Kerr and the motion of a relativistic string in Minkowski space. Path II starts by introducing scalar field theory on Minkowski space as a limit of point masses connected by springs, emphasising the action principle, conservation laws and the energy-momentum tensor. The action principle for electromagnetism is introduced, and the coupling of electromagnetism to a complex scalar field is developed in a detailed and pedagogical fashion. A free symmetric second-rank tensor field on Minkowski space is introduced, and the action principle of general relativity is recovered from coupling the second-rank tensor to its own energy-momentum tensor. Path II then merges with Path I and, supplanted with judicious early selections from Path I, can proceed to the Schwarzschild solution. The choice of material in each path is logical and focused. A notable example in Path I is that Lorentz transformations in Minkowki space are introduced

The renaissance of general relativity

International Nuclear Information System (INIS)

Will, C.

1989-01-01

A historical evaluation of Einstein's theory of general relativity is presented, including the three classical tests of the theory. Gravitation is shown to be a ''curved spacetime'' phenomenon, particularly if the Einstein equivalence principle (EEP) is true. The article traces the success and failures of the theory over the years and up to the present. The concept of gravitation waves was, for example, strengthened by the discovery of a binary pulsar in 1974. The author describes the theory's relevance to neutron stars and black holes and its role in establishing the hot big bang model of cosmological evolution. The article concludes by considering the possibility of antigravity and how gravitational calculations can be done by computer because of the large number of variables in the calculations. (U.K.)

The general dispersion relation of induced streaming instabilities in quantum outflow systems

Energy Technology Data Exchange (ETDEWEB)

Mehdian, H., E-mail: mehdian@khu.ac.ir; Hajisharifi, K.; Hasanbeigi, A. [Department of Physics and Institute for Plasma Research, Kharazmi University, 49 Dr Mofatteh Avenue, Tehran 15614 (Iran, Islamic Republic of)

2015-11-15

In this manuscript the dispersion relations of streaming instabilities, by using the unique property (neutralized in charge and current by default) of plasma shells colliding, have been generalized and studied. This interesting property for interpenetrating beams enables one to find the general dispersion relations without any restrictions used in the previous works in this area. In our previous work [H. Mehdian et al., ApJ. 801, 89 (2015)], employing the plasma shell concept and boost frame method, the general dispersion relation for filamentation instability has been derived in the relativistic classical regime. But in this paper, using the above mentioned concepts, the general dispersion relations (for each of streaming instabilities, filamentation, two-stream and multi-stream) in the non-relativistic quantum regime have been derived by employing the quantum fluid equations together with Maxwell equations. The derived dispersion relations enable to describe any arbitrary system of interacting two and three beams, justified neutralization condition, by choosing the inertial reference frame embedded on the one of the beams. Furthermore, by the numerical and analytical study of these dispersion relations, many new features of streaming instabilities (E.g. their cut-off wave numbers and growth rates) in terms of all involved parameters have been illustrated. The obtained results in this paper can be used to describe many astrophysical systems and laboratory astrophysics setting, such as collision of non-parallel plasma shells over a background plasma or the collision of three neutralized plasma slabs, and justifying the many plasma phenomena such as particle accelerations and induced fields.

Twistors in general relativity

International Nuclear Information System (INIS)

Penrose, R.

1987-01-01

The two most significant definitions of a twistor in (conformally) flat space-time are that given by solutions of the twistor equation and that given by α-planes in the complexification of the space-time. It is shown that these concepts are naturally dual to one another, and that they give rise to various different twistor concepts in curved space-time when referred to submanifolds of differing dimension. One of these concepts, that of 2-surface twistors, gives rise to a quasi-local definition of mass (and angular momentum). The status of this definition is explored in relation to various examples. (author)

A possible generalization of the concept of symmetry in analytical mechanics

International Nuclear Information System (INIS)

Grigore, D.R.

1987-09-01

A theorem of Lee Hwa Chung suggests a possible generalization of the symmetry concept in classical mechanics. It is shown that the theory of Konstant-Souriau-Kirillov can be adapted to this more general case. The theory is illustrated with a number of exaples.(author)

Seeding science success: Relations of secondary students' science self-concepts and motivation with aspirations and achievement

Science.gov (United States)

Chandrasena, Wanasinghe Durayalage

This research comprises three inter-related synergistic studies. Study 1 aims to develop a psychometrically sound tool to measure secondary students' science self-concepts, motivation, and aspirations in biology, chemistry, earth and environmental methodology to explicate students' and teachers' views, practices, and personal experiences, to identify the barriers to undertaking science for secondary students and to provide rich insights into the relations of secondary students' science self-concepts and motivation with their aspirations and achievement. Study 3 will detect additional issues that may not necessarily be identifiable from the quantitative findings of Study 2. The psychometric properties of the newly developed instrument demonstrated that students' science self-concepts were domain specific, while science motivation and science aspirations were not. Students' self-concepts in general science, chemistry, and physics were stronger for males than females. Students' self-concepts in general science and biology became stronger for students in higher years of secondary schooling. Students' science motivation did not vary across gender and year levels. Though students' science aspirations did not vary across gender, they became stronger with age. In general, students' science self-concepts and science motivation were positively related to science aspirations and science achievement. Specifically, students' year level, biology self-concept, and physics self concept predicted their science and career aspirations. Biology self-concept predicted teacher ratings of students' achievement, and students' general science self-concepts predicted their achievement according to students' ratings. Students' year level and intrinsic motivation in science were predictors of their science aspirations, and intrinsic motivation was a greater significant predictor of students' achievement, according to student ratings. Based upon students' and teachers' perceptions, the

Measuring the Computer-Related Self-Concept

Science.gov (United States)

Langheinrich, Jessica; Schönfelder, Mona; Bogner, Franz X.

2016-01-01

A positive self-concept supposedly affects a student's well-being as well as his or her perception of individual competence at school. As computer-based learning is becoming increasingly important in school, a positive computer-related self-concept (CSC) might help to enhance cognitive achievement. Consequently, we focused on establishing a short,…

Astrometric tests of General Relativity in the Solar system

International Nuclear Information System (INIS)

Gai, M; Vecchiato, A; Riva, A; Lattanzi, M G; Sozzetti, A; Crosta, M T; Busonero, D

2014-01-01

Micro-arcsec astronomy is able to verify the predictions of theoretical models of gravitation at a level adequate to constraint relevant parameters and select among different formulations. In particular, this concerns the weak field limit applicable to the Sun neighborhood, where competing models can be expressed in a common framework as the Parametrised Post-Newtonian and Parametrised Post-Post-Newtonian formulations. The mission Gaia is going to provide an unprecedented determination of the γ PPN parameter at the 10 −6 level. Other recently proposed concepts, as GAME, may improve the precision on γ by one or two orders of magnitude and provide constraints on other crucial phenomenological aspects. We review the key concepts of astrometric tests of General Relativity and discuss a possible development scenario

[The concept of health in the General Health Law (1986)].

Science.gov (United States)

Peral, D

1993-01-01

The 1986 "Le General de Sanidad" (Sanitary General Regulations) has been studied using the method of the "Topología del Discurso" in order to elucidate what are the thoughts of the lawmakers. The law protects not only the population of catastrophes as it happened with the choleric epidemic of the XIX century, but considers a new concept a sanitary wealth should be provided to the individuals. Together with this new concept there are new ones such as equality and universalization of the sanitary assistence that would be keys of the aim of the lawmakers: to coordinate all the State resources in the reform of the spanish sanity. This includes the integration of the Universities. This can help in the understanding of the dificulties in the development and aplication of the Law present reality.

The concept of "psychosomatic" in general practice. Reflections on body language and a tentative model for understanding.

Science.gov (United States)

Mattsson, Bengt; Mattsson, Monica

2002-09-01

In medicine, the concept "psychosomatic" indicates both dualism and polarisation. "Could it mean something psychic or is it something somatic?" This artificial dichotomy and body/mind split is not as apparent in general practice as it is in other medical disciplines. In general practice, the prerequisites for a division are overlooked. Following the work of Piaget, the article outlines manifestations of a body/mind unity as exposed in the language. Words and expressions describing the way we move, stand and walk therefore indicate our attitude and state of mind. Our body language conveys a message. The importance of breathing and its relation to our emotions is highlighted. The function of breathing is said to represent a bridge between the conscious and the unconscious--breathing can be controlled by our will, but generally we breathe reflexively. Restricted breathing is not just a mechanical process; it is shown that there is a connection between breathing and our emotions. Finally, a model of the "human organism" is presented linking four concepts, "human activity", "organ functions", "physical body" and "neurophysiological functions". Activities within the different systems are linked and relate to each other. The model supports the necessity to overcome the body/mind split, which is one of the obstacles to the fulfillment of good quality general practice.

Concepts and recent advances in generalized information measures and statistics

CERN Document Server

Kowalski, Andres M

2013-01-01

Since the introduction of the information measure widely known as Shannon entropy, quantifiers based on information theory and concepts such as entropic forms and statistical complexities have proven to be useful in diverse scientific research fields. This book contains introductory tutorials suitable for the general reader, together with chapters dedicated to the basic concepts of the most frequently employed information measures or quantifiers and their recent applications to different areas, including physics, biology, medicine, economics, communication and social sciences. As these quantif

The dynamics of generalization: From fuzzy linguistic statements to concepts and constructs

Energy Technology Data Exchange (ETDEWEB)

Kohout, L.J. [Florida State Univ., Tallahassee, FL (United States)

1996-12-31

Because of the importance of generalization, it is rather surprising that one finds less information in the literature on the nature and character of the process of generalization than one would expect. Some attention is paid to the mechanism of generalization in philosophy, artificial intelligence and cognitive science. In the AI literature, the notion of generalization appears most frequently in connection with learning. Learning through description generalization or specialization is usually performed in one of the following ways: (i) general-to-specific way (G-S), (ii) specific-to-general way (S-G). In S-G approaches the aim is to find a minimal general description that includes all the possible instances of some concept in the knowledge or data base without including any negative instances. So, the S-G approach leads to the set of concept descriptors that are more general than the input set from which it is derived. Problem that any universal generalization must face is the problem of exceptions. In logic, one way of handling exceptions is non-monotonic reasoning. Another example of an AI device that can generalize is a Neural Network (NN) used for classification of patterns. Advantages and disadvantages of this approach will be discussed.

Academic self-concept in children with epilepsy and its relation to their quality of life.

Science.gov (United States)

Brabcova, Dana; Krsek, Pavel; Kohout, Jiri; Jost, Jiri; Zarubova, Jana

2015-04-01

Academic achievement in children with epilepsy is a highly studied topic with many important implications. However, only little attention has been devoted to academic self-concept of such children and the relation of academic self-concept to their quality of life. We aimed to examine academic self-concept in children with epilepsy, to assess its relationship to academic achievement and to determine possible correlations between academic self-concept and quality of life. The study group consisted of 182 children and adolescents aged 9-14 years who completed the student's perception of ability scale (SPAS) questionnaire to determine their academic self-concept and the modified Czech version of the CHEQOL-25 questionnaire to determine their health-related quality of life. We found that academic self-concept in children with epilepsy was on average significantly lower than in their peers without seizures, especially with regard to general school-related abilities, reading, and spelling. On the other hand, the variance in the data obtained from the group of children with epilepsy was significantly higher than in the whole population and the proportion of individuals with very high academic self-concept seems comparable among children with and without epilepsy. Moreover, it was found that correlations between academic self-concept and academic achievement are significantly lower in children with epilepsy than in the whole population. The presented results suggest that considerable attention should be paid to the role of academic self-concept in education of children with epilepsy and to the factors influencing this self-concept in this group.

Forces in General Relativity

Science.gov (United States)

Ridgely, Charles T.

2010-01-01

Many textbooks dealing with general relativity do not demonstrate the derivation of forces in enough detail. The analyses presented herein demonstrate straightforward methods for computing forces by way of general relativity. Covariant divergence of the stress-energy-momentum tensor is used to derive a general expression of the force experienced…

New general relativity

International Nuclear Information System (INIS)

Hayashi, K.; Shirafuji, T.

1979-01-01

A gravitational theory is formulated on the Weitzenboeck space-time, characterized by the vanishing curvature tensor (absolute parallelism) and by the torsion tensor formed of four parallel vector fields. This theory is called new general relativity, since Einstein in 1928 first gave its original form. New general relativity has three parameters c 1 , c 2 , and lambda, besides the Einstein constant kappa. In this paper we choose c 1 = 0 = c 2 , leaving open lambda. We prove, among other things, that (i) a static, spherically symmetric gravitational field is given by the Schwarzschild metric, that (ii) in the weak-field approximation an antisymmetric field of zero mass and zero spin exists, besides gravitons, and that (iii) new general relativity agrees with all the experiments so far carried out

Is Being Gifted Always an Advantage? Peer Relations and Self-Concept of Gifted Students

Science.gov (United States)

Košir, Katja; Horvat, Marina; Aram, Urška; Jurinec, Nina

2016-01-01

The purpose of this study was to investigate the differences between identified gifted adolescents and adolescents not identified as gifted in terms of social acceptance and self-concept (peer relations, academic, and general). In addition, we aimed to investigate the differences between two groups of students identified according to different…

Advanced mechanics and general relativity an introduction to general relativity

CERN Document Server

Franklin, Joel

2010-01-01

Aimed at advanced undergraduates with background knowledge of classical mechanics and electricity and magnetism, this textbook presents both the particle dynamics relevant to general relativity, and the field dynamics necessary to understand the theory. Focusing on action extremization, the book develops the structure and predictions of general relativity by analogy with familiar physical systems. Topics ranging from classical field theory to minimal surfaces and relativistic strings are covered in a homogeneous manner. Nearly 150 exercises and numerous examples throughout the textbook enable students to test their understanding of the material covered.

A general theory of quantum relativity

International Nuclear Information System (INIS)

Minic, Djordje; Tze, C.-H.

2004-01-01

The geometric form of standard quantum mechanics is compatible with the two postulates: (1) the laws of physics are invariant under the choice of experimental setup and (2) every quantum observation or event is intrinsically statistical. These postulates remain compatible within a background independent extension of quantum theory with a local intrinsic time implying the relativity of the concept of a quantum event. In this extension the space of quantum events becomes dynamical and only individual quantum events make sense observationally. At the core of such a general theory of quantum relativity is the three-way interplay between the symplectic form, the dynamical metric and non-integrable almost complex structure of the space of quantum events. Such a formulation provides a missing conceptual ingredient in the search for a background independent quantum theory of gravity and matter. The crucial new technical element in our scheme derives from a set of recent mathematical results on certain infinite-dimensional almost Kahler manifolds which replace the complex projective spaces of standard quantum mechanics

Generalized concepts for measures in case of nuclear and radiological emergencies; Generalisierte Konzepte fuer Massnahmen bei nuklearen und radiologischen Notfaellen

Energy Technology Data Exchange (ETDEWEB)

Sogalla, Martin; Buettner, Uwe; Schnadt, Horst

2015-05-15

In the frame of the project 3610S60014 GRS has developed a generalized concept of measures for an improved availability of support and information systems for emergency purposes and the planning of press and public relations that shall be applicable for the complete spectrum of nuclear end radiological emergencies. The concept allows the derivation of criteria and clear procedures for the situation evaluation and decision making. The project is aimed to integrate all available measure concepts from external emergency preparedness, prevention of ABD hazards and specific nuclear emergency plans.

General relativity basics and beyond

CERN Document Server

Date, Ghanashyam

2015-01-01

A Broad Perspective on the Theory of General Relativity and Its Observable Implications General Relativity: Basics and Beyond familiarizes students and beginning researchers with the basic features of the theory of general relativity as well as some of its more advanced aspects. Employing the pedagogical style of a textbook, it includes essential ideas and just enough background material needed for readers to appreciate the issues and current research. Basics The first five chapters form the core of an introductory course on general relativity. The author traces Einstein’s arguments and presents examples of space-times corresponding to different types of gravitational fields. He discusses the adaptation of dynamics in a Riemannian geometry framework, the Einstein equation and its elementary properties, and different phenomena predicted or influenced by general relativity. Beyond Moving on to more sophisticated features of general relativity, the book presents the physical requirements of a well-defined de...

Discovering Related Clinical Concepts Using Large Amounts of Clinical Notes.

Science.gov (United States)

Ganesan, Kavita; Lloyd, Shane; Sarkar, Vikren

2016-01-01

The ability to find highly related clinical concepts is essential for many applications such as for hypothesis generation, query expansion for medical literature search, search results filtering, ICD-10 code filtering and many other applications. While manually constructed medical terminologies such as SNOMED CT can surface certain related concepts, these terminologies are inadequate as they depend on expertise of several subject matter experts making the terminology curation process open to geographic and language bias. In addition, these terminologies also provide no quantifiable evidence on how related the concepts are. In this work, we explore an unsupervised graphical approach to mine related concepts by leveraging the volume within large amounts of clinical notes. Our evaluation shows that we are able to use a data driven approach to discovering highly related concepts for various search terms including medications, symptoms and diseases.

Discovering Related Clinical Concepts Using Large Amounts of Clinical Notes

Directory of Open Access Journals (Sweden)

Kavita Ganesan

2016-01-01

Full Text Available The ability to find highly related clinical concepts is essential for many applications such as for hypothesis generation, query expansion for medical literature search, search results filtering, ICD-10 code filtering and many other applications. While manually constructed medical terminologies such as SNOMED CT can surface certain related concepts, these terminologies are inadequate as they depend on expertise of several subject matter experts making the terminology curation process open to geographic and language bias. In addition, these terminologies also provide no quantifiable evidence on how related the concepts are. In this work, we explore an unsupervised graphical approach to mine related concepts by leveraging the volume within large amounts of clinical notes. Our evaluation shows that we are able to use a data driven approach to discovering highly related concepts for various search terms including medications, symptoms and diseases.

NICOLAS MALEBRANCHE: FROM THE THEORY OF “GENERAL WILL” TO THE CONCEPT OF “INCLINATION”

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CRISTIAN MOISUC

2014-11-01

Full Text Available The period between 1670 and 1740 is considered a time of “crisis of Christian rationalism” (A. McKenna or a time of “skepticism” (V.Cousin, since the Christian apologetics, trapped between Protestantism and the Rationalism, are gradually reduced to a row of inefficient and traditional “proofs” for the existence and kindness of God. In 1680, Nicolas Malebranche publishes the Treatise on Nature and Grace, following to explain the way in which God granted His grace to all mankind. In order to fight the skeptical thesis according to which God takes not directly part in this world, Malebranche refers the action of God to the concept of “general/divine will”. If such a theory is useful at a certain metaphysical level in explaining the presence of the evil in the world (God does not create but allows the evil, it raises some anthropological issues, especially concerning the nature of the human free will. If anything in the world emerges as a direct consequence of God’s “general will”, how can be conceived a real free human will? The theory of God’s general will generates an unexpected anthropological consequence (the dissolution of the human free will that Malebranche tries to hide it by inventing the concept of “inclination of the will”: God does not interfere (by causation with the human will, but He influences it (by inclination. Is it philosophically defensible? The aim of the article is to analyze some philosophical and methodological difficulties related to the new Malebranchist concept of “inclination of human will” in order to prove that the passage from the occasionalist theory of general will to an inquiry about the human will is quite problematic.

Relational conceptions of paternalism: a way to rebut nanny-state accusations and evaluate public health interventions.

Science.gov (United States)

Carter, S M; Entwistle, V A; Little, M

2015-08-01

'Nanny-state' accusations can function as powerful rhetorical weapons against interventions intended to promote public health. Public health advocates often lack effective rebuttals to these criticisms. Nanny-state accusations are largely accusations of paternalism. They conjure up emotive concern about undue governmental interference undermining peoples' autonomy. But autonomy can be understood in various ways. We outline three main conceptions of autonomy, argue that these that can underpin three different conceptions of paternalism, and consider implications for responses to nanny-state accusations and the assessment of public health interventions. Detailed conceptual analysis. The conceptions of paternalism implicit in nanny-state accusations generally depend on libertarian conceptions of autonomy. These reflect unrealistic views of personal independence and do not discriminate sufficiently between trivial and important freedoms. Decisional conceptions of paternalism, like their underlying decisional conceptions of autonomy, have limited applicability in public health contexts. Relational conceptions of paternalism incorporate relational conceptions of autonomy, so recognize that personal autonomy depends on socially shaped skills, self-identities and self-evaluations as well as externally structured opportunities. They encourage attention to the various ways that social interactions and relationships, including disrespect, stigmatization and oppression, can undermine potential for autonomy. While nanny-state accusations target any interference with negative freedom, however trivial, relational conceptions direct concerns to those infringements of negative freedom, or absences of positive freedom, serious enough to undermine self-determination, self-governance and/or self-authorization. Relational conceptions of autonomy and paternalism offer public health policymakers and practitioners a means for rebutting nanny-state accusations, and can support more nuanced

The Implementation of Physics Problem Solving Strategy Combined with Concept Map in General Physics Course

Science.gov (United States)

Hidayati, H.; Ramli, R.

2018-04-01

This paper aims to provide a description of the implementation of Physic Problem Solving strategy combined with concept maps in General Physics learning at Department of Physics, Universitas Negeri Padang. Action research has been conducted in two cycles where each end of the cycle is reflected and improved for the next cycle. Implementation of Physics Problem Solving strategy combined with concept map can increase student activity in solving general physics problem with an average increase of 15% and can improve student learning outcomes from 42,7 in the cycle I become 62,7 in cycle II in general physics at the Universitas Negeri Padang. In the future, the implementation of Physic Problem Solving strategy combined with concept maps will need to be considered in Physics courses.

Gender differences in the causal relation between adolescents' maths self-concept and scholastic performance

Directory of Open Access Journals (Sweden)

Cristina Antunes

2007-05-01

Full Text Available Mathematics is a core subject in every school curriculum and it is strongly correlated with maths self-concept, which is defined as the subjective feelings and beliefs about one's competence in maths. In general, boys tend to report higher maths self-concept than girls, but the difference between boys and girls' maths scholastic performance is low or even inexistent. Some authors maintain that academic self-concept can play an important role as a motivational variable, promoting self-confidence and investment in the learning process. This study examined the causal relations between maths self-concept and maths scholastic performance in four cohorts of boys and girls within a three-wave longitudinal study. The first two cohorts were composed of 187 girls and 139 boys attending grades 7 and 8 at Time 1 and the third and fourth cohorts were composed of 167 girls and 123 boys attending grades 9 and 10 at Time 1. Structural Equation Modelling was used to test the fit of several models of causal relations. The results revealed that for the first two cohorts the best models were reciprocal and skill-development for both boys and girls. However, for the older students, a reciprocal model gave a best fit for the boys, but for the girls there was only one significant effect from maths self-concept to maths scholastic performance. Results are discussed on the basis of gender-related differential learning expectancies.

Reconsidering relations between nuclear energy and security concepts

International Nuclear Information System (INIS)

Irie, Kazutomo

2004-01-01

Relations between nuclear energy and security concepts can be clarified through investigation into the multivocal nature of security concepts. While military uses of nuclear energy significantly influence national security, peaceful uses of nuclear energy contribute energy security, which is an expanded concept of national security. Military and peaceful uses of nuclear energy have reciprocal actions, thus influencing national security and energy security, respectively. Nuclear security, which means security of nuclear systems themselves, recently attracts the attention of the international society. Nuclear security directly influences national security issues. On the other hand, along with nuclear safety, nuclear security becomes a prerequisite for energy security through peaceful uses of nuclear energy. In investigating into relations between nuclear energy and security concepts, the difficulty of translating the English word of 'nuclear security' into Japanese as well as other languages is found. (author)

A logic road from special relativity to general relativity

OpenAIRE

Andréka, Hajnal; Madarász, Judit X.; Németi, István; Székely, Gergely

2010-01-01

We present a streamlined axiom system of special relativity in first-order logic. From this axiom system we "derive" an axiom system of general relativity in two natural steps. We will also see how the axioms of special relativity transform into those of general relativity. This way we hope to make general relativity more accessible for the non-specialist.

Self-concept and academic achievement: a meta-analysis of longitudinal relations.

Science.gov (United States)

Huang, Chiungjung

2011-10-01

The relation between self-concept and academic achievement was examined in 39 independent and longitudinal samples through the integration of meta-analysis and path analysis procedures. For relations with more than 3 independent samples, the mean observed correlations ranged from .20 to .27 between prior self-concept and subsequent academic achievement and from .19 to .25 between prior academic achievement and subsequent self-concept. Globality/specificity of self-concept was the only significant moderating factor in the relation between (a) prior self-concept and subsequent academic achievement and (b) prior academic achievement and subsequent self-concept. As high self-concept is related to high academic performance and vice-versa, intervention programs that combine self-enhancement and skill development should be integrated. Copyright © 2011 Society for the Study of School Psychology. Published by Elsevier Ltd. All rights reserved.

Forces in general relativity

International Nuclear Information System (INIS)

Ridgely, Charles T

2010-01-01

Many textbooks dealing with general relativity do not demonstrate the derivation of forces in enough detail. The analyses presented herein demonstrate straightforward methods for computing forces by way of general relativity. Covariant divergence of the stress-energy-momentum tensor is used to derive a general expression of the force experienced by an observer in general coordinates. The general force is then applied to the local co-moving coordinate system of a uniformly accelerating observer, leading to an expression of the inertial force experienced by the observer. Next, applying the general force in Schwarzschild coordinates is shown to lead to familiar expressions of the gravitational force. As a more complex demonstration, the general force is applied to an observer in Boyer-Lindquist coordinates near a rotating, Kerr black hole. It is then shown that when the angular momentum of the black hole goes to zero, the force on the observer reduces to the force on an observer held stationary in Schwarzschild coordinates. As a final consideration, the force on an observer moving in rotating coordinates is derived. Expressing the force in terms of Christoffel symbols in rotating coordinates leads to familiar expressions of the centrifugal and Coriolis forces on the observer. It is envisioned that the techniques presented herein will be most useful to graduate level students, as well as those undergraduate students having experience with general relativity and tensor analysis.

Bimetric general relativity

International Nuclear Information System (INIS)

Rosen, N.

1979-01-01

A modification of general relativity is proposed involving a second metric tensor describing a space-time of constant curvature and associated with the fundamental rest-frame of the universe. The theory generally agrees with the Einstein theory, but gives cosmological models without singularities which can account for present observation, including helium abundance

Yarbus's Conceptions on the General Mechanisms of Color Perception.

Science.gov (United States)

Nikolaev, Petr P; Rozhkova, Galina I

2015-01-01

In the last series of papers published during 1975 to 1980, Alfred Yarbus tried to formulate general conceptions concerning the basic principles of retinal image processing in the human visual system. The original ideas of Yarbus were based on the results of his numerous and various experiments carried out with extraordinary inventiveness and great skill. Being concentrated primarily on the problems of color vision, Alfred Yarbus dreamed of elaborating a comprehensive model that would simulate visual information processing at the monocular precognitive level in the visual system of humans with normal trichromatic color perception. In this article, the most important of Yarbus' experimental paradigms, findings, statements, and conclusions are systematized and considered in relation to the classical theories of color perception and, in particular, fundamental theses of the Nyberg school. The perceptual model developed by Alfred Yarbus remained incomplete. Nevertheless, it is already evident that some intrinsic contradictions make it inadequate in terms of comprehensive modeling. However, certain partial advantages deserve more thorough appreciation and further investigation. © The Author(s) 2015.

Lectures on general relativity

CERN Document Server

Papapetrou, Achille

1974-01-01

This book is an elaboration of lecture notes for the graduate course on General Rela­ tivity given by the author at Boston University in the spring semester of 1972. It is an introduction to the subject only, as the time available for the course was limited. The author of an introduction to General Relativity is faced from the beginning with the difficult task of choosing which material to include. A general criterion as­ sisting in this choice is provided by the didactic character of the book: Those chapters have to be included in priority, which will be most useful to the reader in enabling him to understand the methods used in General Relativity, the results obtained so far and possibly the problems still to be solved. This criterion is not sufficient to ensure a unique choice. General Relativity has developed to such a degree, that it is impossible to include in an introductory textbook of a reasonable length even a very condensed treatment of all important problems which have been discussed unt...

Concept relation discovery and innovation enabling technology (CORDIET)

NARCIS (Netherlands)

Poelmans, J.; Elzinga, P.; Neznanov, A.; Viaene, S.; Kuznetsov, S.O.; Ignatov, D.; Dedene, G.

2011-01-01

Concept Relation Discovery and Innovation Enabling Technology (CORDIET), is a toolbox for gaining new knowledge from unstructured text data. At the core of CORDIET is the C-K theory which captures the essential elements of innovation. The tool uses Formal Concept Analysis (FCA), Emergent Self

Self-concept mediates the relation between achievement and emotions in mathematics.

Science.gov (United States)

Van der Beek, Jojanneke P J; Van der Ven, Sanne H G; Kroesbergen, Evelyn H; Leseman, Paul P M

2017-09-01

Mathematics achievement is related to positive and negative emotions. Pekrun's control-value theory of achievement emotions suggests that students' self-concept (i.e., self-appraisal of ability) may be an important mediator of the relation between mathematics achievement and emotions. The aims were (1) to investigate the mediating role of mathematical self-concept in the relation between mathematics achievement and the achievement emotions of enjoyment and anxiety in a comprehensive model, and (2) to test possible differences in this mediating role between low-, average-, and high-achieving students. Participants were ninth-grade students (n = 1,014) from eight secondary schools in the Netherlands. Through an online survey including mathematical problems, students were asked to indicate their levels of mathematics enjoyment, anxiety, and self-concept. Structural equation modelling was used to test the mediating role of self-concept in the relation between mathematics achievement and emotions. Multigroup analyses were performed to compare these relations across the three achievement groups. Results confirmed full mediation of the relation between mathematics achievement and emotions by mathematical self-concept. Furthermore, we found higher self-concepts, more enjoyment and less math anxiety in high-achieving students compared to their average and low-achieving peers. No differences across these achievement groups were found in the relations in the mediational model. Mathematical self-concept plays a pivotal role in students' appraisal of mathematics. Mathematics achievement is only one factor explaining students' self-concept. Likely also classroom instruction and teachers' feedback strategies help to shape students' self-concept. © 2017 The British Psychological Society.

Theory of Nonlocal Point Transformations in General Relativity

Directory of Open Access Journals (Sweden)

Massimo Tessarotto

2016-01-01

Full Text Available A discussion of the functional setting customarily adopted in General Relativity (GR is proposed. This is based on the introduction of the notion of nonlocal point transformations (NLPTs. While allowing the extension of the traditional concept of GR-reference frame, NLPTs are important because they permit the explicit determination of the map between intrinsically different and generally curved space-times expressed in arbitrary coordinate systems. For this purpose in the paper the mathematical foundations of NLPT-theory are laid down and basic physical implications are considered. In particular, explicit applications of the theory are proposed, which concern (1 a solution to the so-called Einstein teleparallel problem in the framework of NLPT-theory; (2 the determination of the tensor transformation laws holding for the acceleration 4-tensor with respect to the group of NLPTs and the identification of NLPT-acceleration effects, namely, the relationship established via general NLPT between particle 4-acceleration tensors existing in different curved space-times; (3 the construction of the nonlocal transformation law connecting different diagonal metric tensors solution to the Einstein field equations; and (4 the diagonalization of nondiagonal metric tensors.

Cosmological tests of general relativity

International Nuclear Information System (INIS)

Hut, P.

1977-01-01

It is stated that the general relativity theory could be tested on a cosmological scale by measuring the Hubble constant and the deceleration parameter, if, in addition, everything could be known about the matter filling the universe. If, on the other hand, nothing could be presupposed about the matter content of the universe general relativity could not be tested by measuring any number of time derivatives of the scale factor. But upon making the assumption of a universe filled with non-interacting mixture of non-relativistic matter and radiation general relativity can in principle be tested by measuring the first five derivatives of the scale factor. Some general relations are here presented using this assumption. (author)

Action Relations. Basic Design Concepts for Behaviour Modelling and Refinement.

NARCIS (Netherlands)

Quartel, Dick

This thesis presents basic design concepts, design methods and a basic design language for distributed system behaviours. This language is based on two basic concepts: the action concept and the causality relation concept. Our methods focus on behaviour refinement, which consists of replacing an

Global general relativity

International Nuclear Information System (INIS)

Penrose, R.

1979-01-01

Much theoretical work in General Relativity has been concerned with finding explicit solutions of Einstein field equations. Exact solutions must involve simplifying procedures which in the case of strong gravitational fields may not be valid. Computers can help but complementary to these are the global qualitative mathematics that have been introduced into relativity over the past years. These have shown that Einstein's equations together with suitable inequalities on the energy-momentum tensor can lead inevitably to space-time singularities arising, provided that some qualitative geometric criterion is satisfied. It seems that in suitable situations of gravitational collapse this criterion will be satisfied. Similarly in a cosmological setting the criterion can be applied in the reverse direction in time. There is, however, the unsolved problem in general relativity of cosmic censorship and this is discussed as a consequence of Einstein's equations. (UK)

General definition of the concept of "sport" as one of the basic constructs of the general theory of physical culture and sports theory

Directory of Open Access Journals (Sweden)

Vasil Sutula

2018-02-01

Full Text Available Purpose: to reveal modern ideas about the essence of the concept of "sport" and determine its role in the development of the general theory of physical culture and sports theory. Material & Methods: analysis of specialized literature, which highlights various aspects of the development of the field of people's activities related to the use of physical exercises. Results: in today's society there is an objective sphere of human activity related to the use of physical exercises, for which the name in domestic and foreign scientific and social practice is most often used the term "physical culture". Conclusion: the constitutive conditions of the process of developing a general theory of physical culture are singled out, it is shown that sport, as a special socio-cultural phenomenon, is a historically conditioned activity of people associated with the use of physical exercises, aimed at preparing and participating in competitions, as well as individual and socially significant results of such activity.

The power of general relativity

International Nuclear Information System (INIS)

Clifton, Timothy; Barrow, John D.

2005-01-01

We study the cosmological and weak-field properties of theories of gravity derived by extending general relativity by means of a Lagrangian proportional to R 1+δ . This scale-free extension reduces to general relativity when δ→0. In order to constrain generalizations of general relativity of this power class, we analyze the behavior of the perfect-fluid Friedmann universes and isolate the physically relevant models of zero curvature. A stable matter-dominated period of evolution requires δ>0 or δ -19 assuming that Mercury follows a timelike geodesic. The combination of these observational constraints leads to the overall bound 0≤δ -19 on theories of this type

Elementary general relativity

International Nuclear Information System (INIS)

Clarke, C.

1979-01-01

The plan of the book is as follows: Chapter 1 develops special relativity in a setting and notation that can immediately be transferred to general relativity. Most of the fundamental geometrical ideas are established here. Chapter 2 gives a more conventional account of some selected applications of special relativity. Chapter 3 is the heart of the book. A geometrical model of space-time is progressively built up, motivated by physical arguments stemming from the equivalence principle, leading to Einstein's field equations. Chapter 4 deals very quickly with the simplest form of weak-field theory with application to gravitational radiation. Chapter 5 concludes the book with a fairly detailed analysis of the Schwarzschild solution, plane fronted gravitational waves, and the Robertson-Walker cosmological solutions. Exercises at the end of each chapter extend the general theory into particular applications, giving a broader picture of the scope of the subject. (author)

Multidimensional Generalized Functions in Aeroacoustics and Fluid Mechanics. Part 1; Basic Concepts and Operations

Science.gov (United States)

Farassat, Fereidoun; Myers, Michael K.

2011-01-01

This paper is the first part of a three part tutorial on multidimensional generalized functions (GFs) and their applications in aeroacoustics and fluid mechanics. The subject is highly fascinating and essential in many areas of science and, in particular, wave propagation problems. In this tutorial, we strive to present rigorously and clearly the basic concepts and the tools that are needed to use GFs in applications effectively and with ease. We give many examples to help the readers in understanding the mathematical ideas presented here. The first part of the tutorial is on the basic concepts of GFs. Here we define GFs, their properties and some common operations on them. We define the important concept of generalized differentiation and then give some interesting elementary and advanced examples on Green's functions and wave propagation problems. Here, the analytic power of GFs in applications is demonstrated with ease and elegance. Part 2 of this tutorial is on the diverse applications of generalized derivatives (GDs). Part 3 is on generalized Fourier transformations and some more advanced topics. One goal of writing this tutorial is to convince readers that, because of their powerful operational properties, GFs are absolutely essential and useful in engineering and physics, particularly in aeroacoustics and fluid mechanics.

Basic concepts in the management of heart failure in general clinical ...

African Journals Online (AJOL)

Basic concepts in the management of heart failure in general clinical practice. KO Ogunyankin. Abstract. No Abstract. Full Text: EMAIL FULL TEXT EMAIL FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT · AJOL African Journals Online. HOW TO USE AJOL... for Researchers · for Librarians · for Authors ...

Pseudo-complex general relativity

CERN Document Server

Hess, Peter O; Greiner, Walter

2016-01-01

This volume presents an pseudo-complex extension of General Relativity which addresses these issues and presents proposals for experimental examinations in strong fields near a large mass. General Relativity is a beautiful and well tested theory of gravitation. Nevertheless, it implies conceptual problems like the creation of singularities (Black Holes) as a result of the collapse of large masses, or the appearance of event horizons which exclude parts of the space-time from the observation of external observers. The mathematical and geometrical foundations of this extension are displayed in detail, and applications including orbits and accretion disks around large central masses, neutron stars or cosmological models are introduced. Calculations both for classical and extended applications are often executed in the form of problems with extensive solutions, which makes this volume also a valuable resource for any student of General Relativity.

A concept analysis of relational aggression.

Science.gov (United States)

Gomes, M M

2007-08-01

The purpose of this article is to conduct a concept analysis of the phenomenon of relational aggression. With the increases in violence among our youth, the topic of aggression, and more specifically relational aggression, has gained an increasing interest. Discussion of relational aggression is imperative because it lends credence to a type of aggression not readily studied in previous decades. A new understanding of relational aggression will aide in future nursing and multidisciplinary research studies and will guide health promotion interventions to alleviate the consequences of relational aggression for adolescent girls. Therefore, with an increased knowledge about the consequences of relational aggression the nurse can provide appropriate nursing interventions to combat the detriment associated with it.

Action principle for the generalized harmonic formulation of general relativity

International Nuclear Information System (INIS)

Brown, J. David

2011-01-01

An action principle for the generalized harmonic formulation of general relativity is presented. The action is a functional of the spacetime metric and the gauge source vector. An action principle for the Z4 formulation of general relativity has been proposed recently by Bona, Bona-Casas, and Palenzuela. The relationship between the generalized harmonic action and the Bona, Bona-Casas, and Palenzuela action is discussed in detail.

Pacifier Overuse and Conceptual Relations of Abstract and Emotional Concepts.

Science.gov (United States)

Barca, Laura; Mazzuca, Claudia; Borghi, Anna M

2017-01-01

This study explores the impact of the extensive use of an oral device since infancy (pacifier) on the acquisition of concrete, abstract, and emotional concepts. While recent evidence showed a negative relation between pacifier use and children's emotional competence (Niedenthal et al., 2012), the possible interaction between use of pacifier and processing of emotional and abstract language has not been investigated. According to recent theories, while all concepts are grounded in sensorimotor experience, abstract concepts activate linguistic and social information more than concrete ones. Specifically, the Words As Social Tools (WAT) proposal predicts that the simulation of their meaning leads to an activation of the mouth (Borghi and Binkofski, 2014; Borghi and Zarcone, 2016). Since the pacifier affects facial mimicry forcing mouth muscles into a static position, we hypothesize its possible interference on acquisition/consolidation of abstract emotional and abstract not-emotional concepts, which are mainly conveyed during social and linguistic interactions, than of concrete concepts. Fifty-nine first grade children, with a history of different frequency of pacifier use, provided oral definitions of the meaning of abstract not-emotional, abstract emotional, and concrete words. Main effect of concept type emerged, with higher accuracy in defining concrete and abstract emotional concepts with respect to abstract not-emotional concepts, independently from pacifier use. Accuracy in definitions was not influenced by the use of pacifier, but correspondence and hierarchical clustering analyses suggest that the use of pacifier differently modulates the conceptual relations elicited by abstract emotional and abstract not-emotional. While the majority of the children produced a similar pattern of conceptual relations, analyses on the few (6) children who overused the pacifier (for more than 3 years) showed that they tend to distinguish less clearly between concrete and

Pacifier Overuse and Conceptual Relations of Abstract and Emotional Concepts

Directory of Open Access Journals (Sweden)

Laura Barca

2017-12-01

Full Text Available This study explores the impact of the extensive use of an oral device since infancy (pacifier on the acquisition of concrete, abstract, and emotional concepts. While recent evidence showed a negative relation between pacifier use and children's emotional competence (Niedenthal et al., 2012, the possible interaction between use of pacifier and processing of emotional and abstract language has not been investigated. According to recent theories, while all concepts are grounded in sensorimotor experience, abstract concepts activate linguistic and social information more than concrete ones. Specifically, the Words As Social Tools (WAT proposal predicts that the simulation of their meaning leads to an activation of the mouth (Borghi and Binkofski, 2014; Borghi and Zarcone, 2016. Since the pacifier affects facial mimicry forcing mouth muscles into a static position, we hypothesize its possible interference on acquisition/consolidation of abstract emotional and abstract not-emotional concepts, which are mainly conveyed during social and linguistic interactions, than of concrete concepts. Fifty-nine first grade children, with a history of different frequency of pacifier use, provided oral definitions of the meaning of abstract not-emotional, abstract emotional, and concrete words. Main effect of concept type emerged, with higher accuracy in defining concrete and abstract emotional concepts with respect to abstract not-emotional concepts, independently from pacifier use. Accuracy in definitions was not influenced by the use of pacifier, but correspondence and hierarchical clustering analyses suggest that the use of pacifier differently modulates the conceptual relations elicited by abstract emotional and abstract not-emotional. While the majority of the children produced a similar pattern of conceptual relations, analyses on the few (6 children who overused the pacifier (for more than 3 years showed that they tend to distinguish less clearly between

General relativity

International Nuclear Information System (INIS)

Gourgoulhon, Eric

2013-01-01

The author proposes a course on general relativity. He first presents a geometrical framework by addressing, presenting and discussion the following notions: the relativistic space-time, the metric tensor, Universe lines, observers, principle of equivalence and geodesics. In the next part, he addresses gravitational fields with spherical symmetry: presentation of the Schwarzschild metrics, radial light geodesics, gravitational spectral shift (Einstein effect), orbitals of material objects, photon trajectories. The next parts address the Einstein equation, black holes, gravitational waves, and cosmological solutions. Appendices propose a discussion of the relationship between relativity and GPS, some problems and their solutions, and Sage codes

Hybrid-source impedance network and its generalized cascading concepts

DEFF Research Database (Denmark)

Li, Ding; Gao, Feng; Loh, Poh Chiang

2009-01-01

Hybrid-source impedance networks have attracted attention among researchers because of their flexibility in performing buck-boost energy conversion. To date, three distinct types of impedance networks can be summarized for implementing voltage-type inverters, with another three types summarized...... for current-type inverters. These impedance networks can in principle be combined into a single generic network entity, before generalized cascading concepts are proposed for connecting multiple of them together to form energy converters with a higher output voltage gain and other unique advantages...

Family Relationships and Adolescent Self-Concept.

Science.gov (United States)

Massey, Catherine J.

Previous research relating the quality of the relationship with the mother, father, and sibling to adolescent self-concept only investigated social and general self-concept and not various social and cognitive dimensions of self-concept. This study investigated family relationships and their link to the several domains of self-concept.…

ALERT. Adverse late effects of cancer treatment. Vol. 1. General concepts and specific precepts

Energy Technology Data Exchange (ETDEWEB)

Rubin, Philip; Constine, Louis S. [Univ. Rochester Medical Center, NY (United States). Dept. of Radiation Oncology; Marks, Lawrence B. (ed.) [Univ. North Carolina and Lineberger, Comprehensive Cancer Center, Chapel Hill, NC (United States). Dept. of Radiation Oncology

2014-09-01

Considers in detail the general concepts and principles relevant to the adverse late effects of cancer treatment. Explains the molecular, cytologic and histopathologic events that lead to altered physiologic and metabolic functions and their clinical manifestations. Includes chapters on legal issues, economic aspects, nursing, psychological issues and quality of life. The literature on the late effects of cancer treatment is widely scattered in different journals since all major organ systems are affected and management is based on a variety of medical and surgical treatments. The aim of ALERT - Adverse Late Effects of Cancer Treatment is to offer a coherent multidisciplinary approach to the care of cancer survivors. The central paradigm is that cytotoxic multimodal therapy results in a perpetual cascade of events that affects each major organ system differently and is expressed continually over time. Essentially, radiation and chemotherapy are intense biologic modifiers that allow for cancer cure and cancer survivorship but accelerate senescence of normal tissues and increase the incidence of age-related diseases and second malignant tumors. Volume 1 of this two-volume work focuses on the general concepts and principles relevant to late effects and on the dynamic interplay of molecular, cytologic and histopathologic events that lead to altered physiologic and metabolic functions and their clinical manifestations. Chapters are also included on legal issues, economic aspects, nursing, psychological issues and quality of life.

ALERT. Adverse late effects of cancer treatment. Vol. 1. General concepts and specific precepts

International Nuclear Information System (INIS)

Rubin, Philip; Constine, Louis S.; Marks, Lawrence B.

2014-01-01

Considers in detail the general concepts and principles relevant to the adverse late effects of cancer treatment. Explains the molecular, cytologic and histopathologic events that lead to altered physiologic and metabolic functions and their clinical manifestations. Includes chapters on legal issues, economic aspects, nursing, psychological issues and quality of life. The literature on the late effects of cancer treatment is widely scattered in different journals since all major organ systems are affected and management is based on a variety of medical and surgical treatments. The aim of ALERT - Adverse Late Effects of Cancer Treatment is to offer a coherent multidisciplinary approach to the care of cancer survivors. The central paradigm is that cytotoxic multimodal therapy results in a perpetual cascade of events that affects each major organ system differently and is expressed continually over time. Essentially, radiation and chemotherapy are intense biologic modifiers that allow for cancer cure and cancer survivorship but accelerate senescence of normal tissues and increase the incidence of age-related diseases and second malignant tumors. Volume 1 of this two-volume work focuses on the general concepts and principles relevant to late effects and on the dynamic interplay of molecular, cytologic and histopathologic events that lead to altered physiologic and metabolic functions and their clinical manifestations. Chapters are also included on legal issues, economic aspects, nursing, psychological issues and quality of life.

Women's toileting behaviour related to urinary elimination: concept analysis.

Science.gov (United States)

Wang, Kefang; Palmer, Mary H

2010-08-01

This paper is a report of analysis of the concept of women's toileting behaviour related to urinary elimination. Behaviours related to emptying urine from the bladder can contribute to bladder health problems. Evidence exists that clinical interventions focusing on specific behaviours that promote urine storage and controlled emptying are effective in reducing lower urinary tract symptoms. The concept of women's toileting behaviour related to urinary elimination has not been well-developed to guide nursing research and intervention. The CINAHL, Medline, PsycInfo and ISI Citation databases were searched for publications between January, 1960 and May, 2009, using combinations of keywords related to women's toileting behaviour. Additional publications were identified by examining the reference lists in the papers identified. Johnson's behavioural system model provided the conceptual framework to identify the concept. Walker and Avant's method was used for this concept analysis. Women's toileting behaviour related to urinary elimination can be defined as voluntary actions related to the physiological event of emptying the bladder, which is comprised of specific attributes including voiding place, voiding time, voiding position and voiding style. This behaviour is also influenced by the physical and social environments. An explicit definition of women's toileting behaviour can offer a basis for nurses to understand the factors involved in women's toileting behaviour. It also facilitates the development of an instrument to assess women's toileting behaviour better, and to facilitate development of behavioural interventions designed to prevent, eliminate, reduce and manage female lower urinary tract symptoms.

Relational Aggression, Victimization and Self-Concept: Testing Pathways from Middle Childhood to Adolescence.

Science.gov (United States)

Blakely-McClure, Sarah J; Ostrov, Jamie M

2016-02-01

When studying adolescent development, it is important to consider two key areas that are salient for teens, which are self-concept and peer relations. A secondary analysis of the National Institute of Health and Human Development Study of Early Child Care and Youth Development was conducted to examine the prospective bidirectional associations between self-concept and peer relations. To date, how social development broadly and peer relations in particular (e.g., relational aggression and victimization) affect self-concept domains is not fully understood. Using a large sample (N = 1063; 532 girls; M = 11.14 years; SD = .59) with multiple informants, the present study examined whether fifth grade relational aggression and sixth grade relational victimization was associated with adolescent self-concept in three key domains (i.e., academic, sports, physical appearance). A significant direct effect emerged, such that relational aggression in middle childhood was associated with decreases in academic self-concept and increases in sports self-concept in adolescence. Analyses also revealed that having higher levels of domain specific self-concept led to decreases in relational aggression across the transition to adolescence. The findings highlight the importance of examining bidirectional prospective associations between relational aggression, relational victimization, and domain specific self-concept. Implications for future research and clinical intervention are discussed.

Modern canonical quantum general relativity

CERN Document Server

Thiemann, Thomas

2007-01-01

This is an introduction to the by now fifteen years old research field of canonical quantum general relativity, sometimes called "loop quantum gravity". The term "modern" in the title refers to the fact that the quantum theory is based on formulating classical general relativity as a theory of connections rather than metrics as compared to in original version due to Arnowitt, Deser and Misner. Canonical quantum general relativity is an attempt to define a mathematically rigorous, non-perturbative, background independent theory of Lorentzian quantum gravity in four spacetime dimensions in the continuum. The approach is minimal in that one simply analyzes the logical consequences of combining the principles of general relativity with the principles of quantum mechanics. The requirement to preserve background independence has lead to new, fascinating mathematical structures which one does not see in perturbative approaches, e.g. a fundamental discreteness of spacetime seems to be a prediction of the theory provi...

Direction dependent structures in general relativity

International Nuclear Information System (INIS)

Herberthson, M.

1993-01-01

This thesis deals with, within the theory of general relativity, asymptotic properties of certain types of space-times. Using conformal transformations, it is possible to describe asymptotic properties of a physical space-time in terms of the local behaviour of the new, rescaled space-time. One then uses so called direction dependent structures. We present two such structures and applications to them. One structure is used in the study of spacelike (or spatial) infinity. We discuss the asymptotic conditions on the gravitational and the electromagnetic field, especially the conditions put on directions corresponding to future and past null infinity. It is shown that these fields have desired physical properties. The other structure is used in connection with timelike infinity. Using this structure, we suggest a new definition of timelike infinity. This definition differs significantly from earlier definitions, and leads to the concept of asymptotically stationary space-times. We also suggest a definition of asymptotic flatness at future null infinity, and a definition of a black hole which is, in a sense, local. Both of these definitions fit nicely into the structure. (24 refs.)

Theoretical general relativity: 1979

International Nuclear Information System (INIS)

Bergmann, O.

1979-01-01

The metric and field equations of Einstein's general relativity theory are written down. Solutions to the equations are discussed. Connection is made between relativity theory and elementary particle theory. Possibilities for a unified field theory are considered

Relation between self-concept and students alcohol drinking

Directory of Open Access Journals (Sweden)

H.M. Fernandes

2009-01-01

Full Text Available This study examines the relation between multiple self-concept dimensions and alcohol consumption within the adolescent schooling. A sample of 642 students (263 boys and 379 girls aged between 15 and 23 years completed the Self-Description Questionnaire II (SDQ II and an alcohol drinking measure. Results reveal an absence of significant relationships between global self-esteem and alcohol consumption and a small relation, found only in the female, between alcoholic drinking and global self-concept, supporting the assumption that supports the low sensitivity and the consequent use of scarce global dimensions of the self. In contrast, there are significant relations between some specific dimensions of the self and alcohol consumption, whilst the correlation coefficients vary according to subject’s gender, suggesting a cultural involvement based analysis.

Relation between self-concept and students alcohol drinking

Directory of Open Access Journals (Sweden)

José Vasconcelos-Raposo

2009-03-01

Full Text Available This study examines the relation between multiple self-concept dimensions and alcohol consumption within the adolescent schooling. A sample of 642 students (263 boys and 379 girls aged between 15 and 23 years completed the Self-Description Questionnaire II (SDQ II and an alcohol drinking measure. Results reveal an absence of significant relationships between global self-esteem and alcohol consumption and a small relation, found only in the female, between alcoholic drinking and global self-concept, supporting the assumption that supports the low sensitivity and the consequent use of scarce global dimensions of the self. In contrast, there are significant relations between some specific dimensions of the self and alcohol consumption, whilst the correlation coefficients vary according to subject’s gender, suggesting a cultural involvement based analysis.

Action Relations. Basic Design Concepts for Behaviour Modelling and Refinement.

OpenAIRE

Quartel, Dick

1998-01-01

This thesis presents basic design concepts, design methods and a basic design language for distributed system behaviours. This language is based on two basic concepts: the action concept and the causality relation concept. Our methods focus on behaviour refinement, which consists of replacing an abstract behaviour by a more concrete behaviour, such that the concrete behaviour conforms to the abstract behaviour. An important idea underlying this thesis is that an effective design methodology s...

Self-esteem, general and sexual self-concepts in blind people

OpenAIRE

Salehi, Mehrdad; Azarbayejani, Abas; Shafiei, Katayoun; Ziaei, Tayebe; Shayegh, Bahar

2015-01-01

Background: People with visual disability have lower self-esteem and social skills than sighted people. This study was designed to describe self-esteem and general and sexual self-concepts in blind people. Materials and Methods: This was a cross-sectional study, conducted in the Isfahan University of Medical Sciences in 2013-2014. In this study, 138 visually impaired people participated from Isfahan Province Welfare Organization and were interviewed for measuring of self-esteem and self-conce...

Culture of Honour and Emotional Intelligence: Incompatible or related concepts?

Directory of Open Access Journals (Sweden)

Esther López-Zafra

2013-11-01

Full Text Available In this study we relate two concepts, Emotional Intelligence and Culture of Honour; in both cases the emotional aspect is very important and we believe they may have a role in couple relations. We propose that both concepts would relate in reverse, so that an individual with a high level of Emotional Intelligence would give less importance to the Culture of Honor and vice versa. A sample of 203 heterosexual couples completed a questionnaire. Our results show that the dimension Attention to emotions is associated with the culture of honor. Among our fi ndings we propose that the two concepts are related in some way and that congruency in the valuation of the Culture of Honor between the two partners will also deal with a level of Emotional Intelligence higher than in couples where there is not this congruence.

A study of school adjustment, self-concept, self-esteem, general wellbeing and parent child relationship in Juvenile Idiopathic Arthritis.

Science.gov (United States)

Yadav, Anita; Yadav, T P

2013-03-01

To assess school adjustment, self-concept, self-esteem, general wellbeing and parent-child relationship in children with Juvenile Idiopathic Arthritis (JIA)and to study the correlation of these parameters with chronicity of disease, number of active joints, laboratory parameters of disease activity and JIA subtypes. A total of 64 children (32 cases and 32 controls) were recruited for analysis. Self report questionnaires which included PGI General Wellbeing Measure, Adjustment Inventory for School Students, Parent Child Relationship Scale, Self Esteem Inventory and Self Concept Questionnaires were used to assess all the enrolled subjects. Cases had significantly lower general physical well being (p self-esteem, self-concept, adjustment in school, general wellbeing and evokes disturbed parent-child relationship.

Spinning fluids in general relativity

Science.gov (United States)

Ray, J. R.; Smalley, L. L.

1982-01-01

General relativity field equations are employed to examine a continuous medium with internal spin. A variational principle formerly applied in the special relativity case is extended to the general relativity case, using a tetrad to express the spin density and the four-velocity of the fluid. An energy-momentum tensor is subsequently defined for a spinning fluid. The equations of motion of the fluid are suggested to be useful in analytical studies of galaxies, for anisotropic Bianchi universes, and for turbulent eddies.

General relativity and gauge gravity theories of higher order

International Nuclear Information System (INIS)

Konopleva, N.P.

1998-01-01

It is a short review of today's gauge gravity theories and their relations with Einstein General Relativity. The conceptions of construction of the gauge gravity theories with higher derivatives are analyzed. GR is regarded as the gauge gravity theory corresponding to the choice of G ∞4 as the local gauge symmetry group and the symmetrical tensor of rank two g μν as the field variable. Using the mathematical technique, single for all fundamental interactions (namely variational formalism for infinite Lie groups), we can obtain Einstein's theory as the gauge theory without any changes. All other gauge approaches lead to non-Einstein theories of gravity. But above-mentioned mathematical technique permits us to construct the gauge gravity theory of higher order (for instance SO (3,1)-gravity) so that all vacuum solutions of Einstein equations are the solutions of the SO (3,1)-gravity theory. The structure of equations of SO(3,1)-gravity becomes analogous to Weeler-Misner geometrodynamics one

Conceptions of the Nature of Science--Are They General or Context Specific?

Science.gov (United States)

Urhahne, Detlef; Kremer, Kerstin; Mayer, Juergen

2011-01-01

The study investigates the relationship between general and context-specific conceptions of the nature of science (NOS). The categorization scheme by Osborne et al. (J Res Sci Teach 40:692-720, "2003") served as the theoretical framework of the study. In the category "nature of scientific knowledge", the certainty, development, simplicity,…

A generalized notion of semantic independence

DEFF Research Database (Denmark)

Fränzle, Martin; Stengel, Bernhard von; Wittmüss, Arne

1995-01-01

For programs represented semantically as relations, a concept of semantic independence is defined that is more general than previously stated notions. It allows for shared input variables and irrelevant interference due to nondeterminism.......For programs represented semantically as relations, a concept of semantic independence is defined that is more general than previously stated notions. It allows for shared input variables and irrelevant interference due to nondeterminism....

Centennial of general relativity a celebration

CERN Document Server

2017-01-01

It has been over 100 years since the presentation of the Theory of General Relativity by Albert Einstein, in its final formulation, to the Royal Prussian Academy of Sciences. To celebrate 100 years of general relativity, World Scientific publishes this volume with a dual goal: to assess the current status of the field of general relativity in broad terms, and discuss future directions. The volume thus consists of broad overviews summarizing major developments over the past decades and their perspective contributions.

Triangular Norms, Triangular Conorms, and Some Related Concepts

Directory of Open Access Journals (Sweden)

Angel Garrido

2011-01-01

Full Text Available Abstract. Mathematically considered, a Triangular Norm is a kind of binary operation frequently used in the context of Probabilistic Metric Spaces, but also in other very interesting fields, as may be Fuzzy Logic, or in general, in Multi-Valued Logic (MVL. The T-conorm, or S-norm, is a dual concept. Both ideas allow us to generalize the intersection and the union in a Lattice, or disjunction and conjunction in Logic. Also may be very interesting to introduce a special class of real monotone operations. We refer to the so-called Copulas, very useful in many fields. So, we offer now a comprehensive analysis of all these aggregation operators.

Relationship of sexual assault with self-concept and general health in victims referred to forensic Center in Ahvaz city.

Science.gov (United States)

Alboebadi, F; Afshari, P; Jamshidi, F; Poor, Rm; Cheraghi, M

We aimed to study the relationship of sexual assault with self-concept and the general health of the victims referred to forensics in Ahvaz city (Iran). It was a cross-sectional descriptive and analytical study that was designed by two groups as case and control which has done on 128 subjects. Sixty-four rape victims who were referred to the forensic center, considered as case group and in control group, 64 people who were being referred to health clinics in Ahvaz city. The data were collected through Rogers's standard self-concept and general health questionnaires. Questionnaires were filled in self-completion way. Data had entered and analyzed by using SPSS software (version 22). A level of significance was less than 0.05. The average score of self-concept in the case group was 14.97 ±4.78 and in control group was 6.08 ±2.9. Average score of general health of the case and control groups, respectively, were 51.09 ±18.07 and 16.92 ±12.79. A significant statistical difference between the average score of self-concept, social functioning, physical and general health components in the groups was observed. More negative self-concept and vulnerable general health was observed in the rape victims group than in the control group. Providing counseling and health services and family and social support of these victims can be effective in their general health promotion.

Bimetric general relativity and cosmology

International Nuclear Information System (INIS)

Rosen, N.

1980-01-01

A modification of the general relativity theory is proposed (bimetric general relativity) in which, in addition to the usual metric tensor gsub(μupsilon) describing the space-time geometry and gravitation, there exists also a background metric tensor γsub(μupsilon). The latter describes the space-time of the universe if no matter were present and is taken to correspond to a space-time of constant curvature with positive spatial curvature (k = 1). Field equations are obtained, and these agree with the Einstein equations for systems that are small compared to the size of the universe, such as the solar system. Energy considerations lead to a generalized form of the De Donder condition. Simple isotropic closed models of the universe can be set up which first contract and then expand without going through a singular state. It is suggested that the maximum density of the universe was of the order of c 5 -h -1 G -2 approximately 10 93 g/cm 3 . The expansion from such a high-density state is similar to that from the singular state ('big bang') of the general relativity models. In the case of the dust-filled model the parameters can be fitted to present cosmological data. Using the radiation-filled model to describe the early history of the universe, the cosmic abundance of helium and other light elements can be accounted for in the same way as in ordinary general relativity. (author)

Einstein's creative thinking and the general theory of relativity: a documented report.

Science.gov (United States)

Rothenberg, A

1979-01-01

A document written by Albert Einstein has recently come to light in which the eminent scientist described the actual sequence of his thoughts leading to the development of the general theory of relativity. The key creative thought was an instance of a type of creative cognition the author has previously designated "Janusian thinking," Janusian thinking consists of actively conceiving two or more opposite or antithetical concepts, ideas, or images simultaneously. This form of high-level secondary process cognition has been found to operate widely in art, science, and other fields.

Self-Concept and Academic Achievement: A Meta-Analysis of Longitudinal Relations

Science.gov (United States)

Huang, Chiungjung

2011-01-01

The relation between self-concept and academic achievement was examined in 39 independent and longitudinal samples through the integration of meta-analysis and path analysis procedures. For relations with more than 3 independent samples, the mean observed correlations ranged from 0.20 to 0.27 between prior self-concept and subsequent academic…

Cosmic frontiers of general relativity

International Nuclear Information System (INIS)

Kaufmann, W.J. III.

1977-01-01

All relevant topics in general astronomy are covered including orientation in space--time, special relativity, gravitation and general relativity, stars and stellar evolution, white dwarfs, pulsars, neutron stars, the black hole, the geometry of the Schwarzschild solution, and electrically charged and rotating black holes. Also the geometry of the Kerr solution, observations of black holes, white holes and particle creation, gravitational waves and lenses, exploding galaxies and massive and primordial black holes are discussed

General Relativity and Gravitation

Science.gov (United States)

Ashtekar, Abhay; Berger, Beverly; Isenberg, James; MacCallum, Malcolm

2015-07-01

Part I. Einstein's Triumph: 1. 100 years of general relativity George F. R. Ellis; 2. Was Einstein right? Clifford M. Will; 3. Cosmology David Wands, Misao Sasaki, Eiichiro Komatsu, Roy Maartens and Malcolm A. H. MacCallum; 4. Relativistic astrophysics Peter Schneider, Ramesh Narayan, Jeffrey E. McClintock, Peter Mészáros and Martin J. Rees; Part II. New Window on the Universe: 5. Receiving gravitational waves Beverly K. Berger, Karsten Danzmann, Gabriela Gonzalez, Andrea Lommen, Guido Mueller, Albrecht Rüdiger and William Joseph Weber; 6. Sources of gravitational waves. Theory and observations Alessandra Buonanno and B. S. Sathyaprakash; Part III. Gravity is Geometry, After All: 7. Probing strong field gravity through numerical simulations Frans Pretorius, Matthew W. Choptuik and Luis Lehner; 8. The initial value problem of general relativity and its implications Gregory J. Galloway, Pengzi Miao and Richard Schoen; 9. Global behavior of solutions to Einstein's equations Stefanos Aretakis, James Isenberg, Vincent Moncrief and Igor Rodnianski; Part IV. Beyond Einstein: 10. Quantum fields in curved space-times Stefan Hollands and Robert M. Wald; 11. From general relativity to quantum gravity Abhay Ashtekar, Martin Reuter and Carlo Rovelli; 12. Quantum gravity via unification Henriette Elvang and Gary T. Horowitz.

Relating Complexity and Error Rates of Ontology Concepts. More Complex NCIt Concepts Have More Errors.

Science.gov (United States)

Min, Hua; Zheng, Ling; Perl, Yehoshua; Halper, Michael; De Coronado, Sherri; Ochs, Christopher

2017-05-18

Ontologies are knowledge structures that lend support to many health-information systems. A study is carried out to assess the quality of ontological concepts based on a measure of their complexity. The results show a relation between complexity of concepts and error rates of concepts. A measure of lateral complexity defined as the number of exhibited role types is used to distinguish between more complex and simpler concepts. Using a framework called an area taxonomy, a kind of abstraction network that summarizes the structural organization of an ontology, concepts are divided into two groups along these lines. Various concepts from each group are then subjected to a two-phase QA analysis to uncover and verify errors and inconsistencies in their modeling. A hierarchy of the National Cancer Institute thesaurus (NCIt) is used as our test-bed. A hypothesis pertaining to the expected error rates of the complex and simple concepts is tested. Our study was done on the NCIt's Biological Process hierarchy. Various errors, including missing roles, incorrect role targets, and incorrectly assigned roles, were discovered and verified in the two phases of our QA analysis. The overall findings confirmed our hypothesis by showing a statistically significant difference between the amounts of errors exhibited by more laterally complex concepts vis-à-vis simpler concepts. QA is an essential part of any ontology's maintenance regimen. In this paper, we reported on the results of a QA study targeting two groups of ontology concepts distinguished by their level of complexity, defined in terms of the number of exhibited role types. The study was carried out on a major component of an important ontology, the NCIt. The findings suggest that more complex concepts tend to have a higher error rate than simpler concepts. These findings can be utilized to guide ongoing efforts in ontology QA.

Relative Effects of Problem-Solving and Concept Mapping ...

African Journals Online (AJOL)

Relative Effects of Problem-Solving and Concept Mapping Instructional ... mapping strategies are also discussed and their significance and importance to students. ... development of problem solving skills before the end of SSCE Programmebr ...

Generalization of risk concept in case risk components depend on time

International Nuclear Information System (INIS)

Volkov, Yu.V.

2006-01-01

Ratios of risk assessments vs. nuclear technologies objects have been obtained for cases when that kind of risk components as accident probability and the consequent damage depend on time. Such generalization of risk concept ensures new possibilities for performing the probabilistic safety analysis which have been demonstrated with simple models in the present paper. As an example safety of radioactive storage with one-component activity has been analyzed with a very simple model [ru

Stochastic quantization of general relativity

International Nuclear Information System (INIS)

Rumpf, H.

1986-01-01

Following an elementary exposition of the basic mathematical concepts used in the theory of stochastic relaxation processes the stochastic quantization method of Parisi and Wu is briefly reviewed. The method is applied to Einstein's theory of gravitation using a formalism that is manifestly covariant with respect to field redefinitions. This requires the adoption of Ito's calculus and the introduction of a metric in field configuration space, for which there is a unique candidate. Due to the indefiniteness of the Euclidean Einstein-Hilbert action stochastic quantization is generalized to the pseudo-Riemannian case. It is formally shown to imply the DeWitt path integral measure. Finally a new type of perturbation theory is developed. (Author)

Energy and Uncertainty in General Relativity

Science.gov (United States)

Cooperstock, F. I.; Dupre, M. J.

2018-03-01

The issue of energy and its potential localizability in general relativity has challenged physicists for more than a century. Many non-invariant measures were proposed over the years but an invariant measure was never found. We discovered the invariant localized energy measure by expanding the domain of investigation from space to spacetime. We note from relativity that the finiteness of the velocity of propagation of interactions necessarily induces indefiniteness in measurements. This is because the elements of actual physical systems being measured as well as their detectors are characterized by entire four-velocity fields, which necessarily leads to information from a measured system being processed by the detector in a spread of time. General relativity adds additional indefiniteness because of the variation in proper time between elements. The uncertainty is encapsulated in a generalized uncertainty principle, in parallel with that of Heisenberg, which incorporates the localized contribution of gravity to energy. This naturally leads to a generalized uncertainty principle for momentum as well. These generalized forms and the gravitational contribution to localized energy would be expected to be of particular importance in the regimes of ultra-strong gravitational fields. We contrast our invariant spacetime energy measure with the standard 3-space energy measure which is familiar from special relativity, appreciating why general relativity demands a measure in spacetime as opposed to 3-space. We illustrate the misconceptions by certain authors of our approach.

Longitudinal relations between symptoms, neurocognition, and self-concept in schizophrenia.

Science.gov (United States)

Hesse, Klaus; Kriston, Levente; Wittorf, Andreas; Herrlich, Jutta; Wölwer, Wolfgang; Klingberg, Stefan

2015-01-01

Cognitive models suggest that the self-concept of persons with psychosis can be fundamentally affected. Self-concepts were found to be related to different symptom domains when measured concurrently. Longitudinal investigations to disentangle the possible causal associations are rare. We examined a sample of 160 people with a diagnosis of schizophrenia who took part in a psychotherapy study. All participants had the DSM-IV diagnosis of a schizophrenia and pronounced negative symptoms. Neurocognition, symptoms, and self-concepts were assessed at two time points 12 months apart. Structural equation modeling was used to test whether symptoms influence self-concepts (scar-model) or self-concepts affect symptoms (vulnerability model). Negative symptoms correlated concurrently with self-concepts. Neurocognitive deficits are associated with more negative self-concepts 12 months later. Interpersonal self-concepts were found to be relevant for paranoia. The findings implicate that if deficits in neurocognition are present, fostering a positive self-concept should be an issue in therapy. Negative interpersonal self-concept indicates an increased risk for paranoid delusions in the course of 1 year. New aspects for cognitive models in schizophrenia and clinical implications are discussed.

Longitudinal relations between symptoms, neurocognition and self-concept in schizophrenia

Directory of Open Access Journals (Sweden)

Klaus eHesse

2015-07-01

Full Text Available Objective: Cognitive models suggest that the self-concept of persons with psychosis can be fundamentally affected. Self-concepts were found to be related to different symptom domains when measured concurrently. Longitudinal investigations to disentangle the possible causal associations are rare. Method: We examined a sample of 160 people with a diagnosis of schizophrenia who took part in a psychotherapy study. All participants had the DSM-IV diagnosis of a schizophrenia and pronounced negative symptoms. Neurocognition, symptoms and self-concepts were assessed at two time points twelve months apart. Structural equation modelling was used to test whether symptoms influence self-concepts (scar-model or self-concepts affect symptoms (vulnerability model. Results: Negative symptoms correlated concurrently with self-concepts. Neurocognitive deficits are associated with more negative self-concepts twelve months later. Interpersonal self-concepts were found to be relevant for paranoia. Conclusion: The findings implicate that if deficits in neurocognition are present, fostering a positive self-concept should be an issue in therapy. Negative interpersonal self-concept indicates an increased risk for paranoid delusions in the course of one year. New aspects for cognitive models in schizophrenia and clinical implications are discussed

Concepts and Relations in Neurally Inspired In Situ Concept-Based Computing.

Science.gov (United States)

van der Velde, Frank

2016-01-01

In situ concept-based computing is based on the notion that conceptual representations in the human brain are "in situ." In this way, they are grounded in perception and action. Examples are neuronal assemblies, whose connection structures develop over time and are distributed over different brain areas. In situ concepts representations cannot be copied or duplicated because that will disrupt their connection structure, and thus the meaning of these concepts. Higher-level cognitive processes, as found in language and reasoning, can be performed with in situ concepts by embedding them in specialized neurally inspired "blackboards." The interactions between the in situ concepts and the blackboards form the basis for in situ concept computing architectures. In these architectures, memory (concepts) and processing are interwoven, in contrast with the separation between memory and processing found in Von Neumann architectures. Because the further development of Von Neumann computing (more, faster, yet power limited) is questionable, in situ concept computing might be an alternative for concept-based computing. In situ concept computing will be illustrated with a recently developed BABI reasoning task. Neurorobotics can play an important role in the development of in situ concept computing because of the development of in situ concept representations derived in scenarios as needed for reasoning tasks. Neurorobotics would also benefit from power limited and in situ concept computing.

Dynamics of relative motion of test particles in general relativity

International Nuclear Information System (INIS)

Bazanski, S.L.

1977-01-01

Several variational principles which lead to the first and the second geodesic deviation equations, recently formulated by the author and used for the description of the relative motion of test particles in general relativity are presented. Relations between these principles are investigated and exhibited. The Hamilton-Jacobi equation is also studied for these generalized deviations and the conservation laws appearing here are discussed

Peer relations in adolescents: effects of parenting and adolescents' self-concept.

Science.gov (United States)

Deković, M; Meeus, W

1997-04-01

In this study we examined the link between the parent-adolescent relationship and the adolescent's relationship with peers. The proposed model assumes that the quality of the parent-child relationship affects the adolescent's self-concept, which in turn affects the adolescent's integration into the world of peers. The sample consisted of 508 families with adolescents (12- to 18-years-old). The data were obtained at the subjects' homes, where a battery of questionnaires was administered individually to mothers, fathers and adolescents. Several constructs relating to the quality of parent-child relationship were assessed: parental acceptance, attachment, involvement, responsiveness, love withdrawal and monitoring of the child. The measures of the adolescent's self-concept included Harter's Perceived Competence Scale for Adolescents and Rosenberg's Self-Esteem Scale. The indicators of the quality of peer relations were: degree of peer activity, having a best friend, perceived acceptance by peers and attachment to peers. Assessment of the hypothesized model showed that the adolescent's self-concept serves a mediating role in the relationship between maternal child-rearing style and involvement with peers. The mediating role of self-concept was greatest for maternal acceptance. Paternal child-rearing style, however, appeared to have an independent effect on the adolescent's involvement with peers that is not accounted for by the adolescent's self-concept. The prediction of the quality of adolescents' peer relations yielded similar results for both mothers and fathers. The results suggest that a positive self-concept and warm supportive parenting each contribute unique variance to satisfactory peer relations.

Matter in general relativity

Science.gov (United States)

Ray, J. R.

1982-01-01

Two theories of matter in general relativity, the fluid theory and the kinetic theory, were studied. Results include: (1) a discussion of various methods of completing the fluid equations; (2) a method of constructing charged general relativistic solutions in kinetic theory; and (3) a proof and discussion of the incompatibility of perfect fluid solutions in anisotropic cosmologies. Interpretations of NASA gravitational experiments using the above mentioned results were started. Two papers were prepared for publications based on this work.

Particle field in bimetric general relativity

International Nuclear Information System (INIS)

Falik, D.; Rosen, N.

1980-01-01

The field equations of the bimetric general relativity theory proposed recently by one of the authors (N. Rosen) are put into a static form. The equations are solved near the Schwarzschild sphere, and it is found that the field differs from that of the Einstein general relativity theory: instead of a black hole, one has an impenetrable sphere. For larger distances the field is found to agree with that of ordinary general relativity, so that solar system observations cannot distinguish between the two theories. For very large distances one gets a cosmic contribution to the field which may affect the dynamics of clusters of galaxies

Compact objects in bimetric general relativity

International Nuclear Information System (INIS)

Harpaz, A.; Rosen, N.

1985-01-01

The field equations of the bimetric general relativity theory proposed by one of the authors (N. Rosen), in the static form, are solved in order to investigate the structure of a star. It is found that for an ordinary star the bimetric theory gives the same results as the Einstein general relativity theory. However, for a collapsed star the two theories give different results. In the bimetric theory a configuration in hydrostatic equilibrium exists for a collapsed star filling its Schwarzschild sphere. In general relativity no equilibrium configuration exists in this region, and the star shrinks to a point singularity to form a black hole

General relativity and gravitational waves

CERN Document Server

Weber, Johanna

1961-01-01

An internationally famous physicist and electrical engineer, the author of this text was a pioneer in the investigation of gravitational waves. Joseph Weber's General Relativity and Gravitational Waves offers a classic treatment of the subject. Appropriate for upper-level undergraduates and graduate students, this text remains ever relevant. Brief but thorough in its introduction to the foundations of general relativity, it also examines the elements of Riemannian geometry and tensor calculus applicable to this field.Approximately a quarter of the contents explores theoretical and experimenta

The Reciprocal Relations between Self-Concept, Motivation and Achievement: Juxtaposing Academic Self-Concept and Achievement Goal Orientations for Mathematics Success

Science.gov (United States)

Seaton, Marjorie; Parker, Philip; Marsh, Herbert W.; Craven, Rhonda G.; Yeung, Alexander Seeshing

2014-01-01

Research suggests that motivated students and those with high academic self-concepts perform better academically. Although substantial evidence supports a reciprocal relation between academic self-concept and achievement, there is less evidence supporting a similar relation between achievement goal orientations and achievement. There is also a…

Testing general relativity on accelerators

Directory of Open Access Journals (Sweden)

Tigran Kalaydzhyan

2015-11-01

Full Text Available Within the general theory of relativity, the curvature of spacetime is related to the energy and momentum of the present matter and radiation. One of the more specific predictions of general relativity is the deflection of light and particle trajectories in the gravitational field of massive objects. Bending angles for electromagnetic waves and light in particular were measured with a high precision. However, the effect of gravity on relativistic massive particles was never studied experimentally. Here we propose and analyze experiments devoted to that purpose. We demonstrate a high sensitivity of the laser Compton scattering at high energy accelerators to the effects of gravity. The main observable – maximal energy of the scattered photons – would experience a significant shift in the ambient gravitational field even for otherwise negligible violation of the equivalence principle. We confirm predictions of general relativity for ultrarelativistic electrons of energy of tens of GeV at a current level of resolution and expect our work to be a starting point of further high-precision studies on current and future accelerators, such as PETRA, European XFEL and ILC.

Humanity as a Contested Concept: Relations between Disability and ‘Being Human’

Directory of Open Access Journals (Sweden)

Paul van Trigt

2016-11-01

Full Text Available This editorial presents the theme and approach of the themed issue “Humanity as a Contested Concept: Relations between Disability and ‘Being Human’”. The way in which the concept of humanity is or must be related to disability is critically investigated from different disciplinary perspectives in the themed issue, which is, moreover, situated in the field of disability studies and related to discussions about posthumanism. The argument is made that humanity is a concept that needs to be constantly reflected upon from a disability studies perspective. Finally, the contributions of the themed issue are briefly outlined.

General relativity and experiment

OpenAIRE

Damour, T.

1994-01-01

The confrontation between Einstein's theory of gravitation and experiment is summarized. Although all current experimental data are compatible with general relativity, the importance of pursuing the quest for possible deviations from Einstein's theory is emphasized.

General Relativity and Gravitation

Science.gov (United States)

Ehlers, J.; Murdin, P.

2000-11-01

The General Theory of Relativity (GR), created by Albert Einstein between 1907 and 1915, is a theory both of gravitation and of spacetime structure. It is based on the assumption that matter, via its energy-momentum, interacts with the metric of spacetime, which is considered (in contrast to Newtonian physics and SPECIAL RELATIVITY) as a dynamical field having degrees of freedom of its own (GRAVI...

Generalized Landau-Pollak uncertainty relation

International Nuclear Information System (INIS)

Miyadera, Takayuki; Imai, Hideki

2007-01-01

The Landau-Pollak uncertainty relation treats a pair of rank one projection valued measures and imposes a restriction on their probability distributions. It gives a nontrivial bound for summation of their maximum values. We give a generalization of this bound (weak version of the Landau-Pollak uncertainty relation). Our generalization covers a pair of positive operator valued measures. A nontrivial but slightly weak inequality that can treat an arbitrary number of positive operator valued measures is also presented. A possible application to the problem of separability criterion is also suggested

General Relativity in (1 + 1) Dimensions

Science.gov (United States)

Boozer, A. D.

2008-01-01

We describe a theory of gravity in (1 + 1) dimensions that can be thought of as a toy model of general relativity. The theory should be a useful pedagogical tool, because it is mathematically much simpler than general relativity but shares much of the same conceptual structure; in particular, it gives a simple illustration of how gravity arises…

Using "Monopoly" to Introduce Concepts of Race and Ethnic Relations

Science.gov (United States)

Waren, Warren

2011-01-01

In this paper I suggest a technique which uses the familiar Parker Brother's game "Monopoly" to introduce core concepts of race and ethnic relations. I offer anecdotes from my classes where an abbreviated version of the game is used as an analog to highlight the sociological concepts of direct institutional discrimination, the legacy of…

Probability concepts in quality risk management.

Science.gov (United States)

Claycamp, H Gregg

2012-01-01

Essentially any concept of risk is built on fundamental concepts of chance, likelihood, or probability. Although risk is generally a probability of loss of something of value, given that a risk-generating event will occur or has occurred, it is ironic that the quality risk management literature and guidelines on quality risk management tools are relatively silent on the meaning and uses of "probability." The probability concept is typically applied by risk managers as a combination of frequency-based calculation and a "degree of belief" meaning of probability. Probability as a concept that is crucial for understanding and managing risk is discussed through examples from the most general, scenario-defining and ranking tools that use probability implicitly to more specific probabilistic tools in risk management. A rich history of probability in risk management applied to other fields suggests that high-quality risk management decisions benefit from the implementation of more thoughtful probability concepts in both risk modeling and risk management. Essentially any concept of risk is built on fundamental concepts of chance, likelihood, or probability. Although "risk" generally describes a probability of loss of something of value, given that a risk-generating event will occur or has occurred, it is ironic that the quality risk management literature and guidelines on quality risk management methodologies and respective tools focus on managing severity but are relatively silent on the in-depth meaning and uses of "probability." Pharmaceutical manufacturers are expanding their use of quality risk management to identify and manage risks to the patient that might occur in phases of the pharmaceutical life cycle from drug development to manufacture, marketing to product discontinuation. A probability concept is typically applied by risk managers as a combination of data-based measures of probability and a subjective "degree of belief" meaning of probability. Probability as

Assessment of fuel concepts

International Nuclear Information System (INIS)

Bailey, W.J.; Barner, J.O.

1978-01-01

The relative merits of various LWR UO 2 fuel concepts with the potential for improved power-ramping capability were qualitatively assessed. In the evaluation, it was determined that of the various concepts being considered, those that presently possess an adequately developed experience base include annular pellets, cladding coated with graphite on the inner surface, and packed-particle fuel. Therefore, these were selected for initial evaluation as part of the Fuel Performance Improvement Program. For this program, graphite-coated cladding is being used in conjunction with annular pellet fuel as one of the concepts with the anticipation of gaining the advantage of the combined improvements. The report discusses the following: the criteria used to evaluate the candidate fuel concepts; a comparison of the concepts selected for irradiation with the criteria, including a general description of their experience bases; and a general discussion of other candidate concepts, including identifying those which may be considered for out-of-reactor evaluation as part of this program, those for which the results of other programs will be monitored, and those which have been deleted from further consideration at this time

Einstein and general relativity: historical perspectives

International Nuclear Information System (INIS)

Chandrasekhar, S.

1978-01-01

The place of Einstein in 20th-century physics is discussed. The basic ideas that led Einstein to his theory of gravitation by the sheer power of speculative thought are described in the most general terms. The prediction of the bending of starlight by the Sun and the eclipse expedition of 1919 are recounted. The author feels that ''the general theory of relativity is incredibly rich in its content;...one finds a glittering face at almost every turn.'' The prediction of black holes by general relativity is noted

General Relativity and Energy

Science.gov (United States)

Jackson, A. T.

1973-01-01

Reviews theoretical and experimental fundamentals of Einstein's theory of general relativity. Indicates that recent development of the theory of the continually expanding universe may lead to revision of the space-time continuum of the finite and unbounded universe. (CC)

CHUVARDINSKY’S ANTIGLACIAL (GENERALIZED GEOLOGICAL CONCEPTION

Directory of Open Access Journals (Sweden)

P. K. Skufyin

2016-12-01

Full Text Available Based on the analytical study of V. G. Chuvardinsky’s monographs on the revision of the generally accepted glacial theory, the authors of the review concluded that there was convincing evidence of a fault-tectonic origin of ‘ice-exaration’ relief of the Baltic Shield. Developed by Chuvardinsky, a radically new methodology of boulder prospecting of ore deposits not only refuted the old glacial theory, but also led to the discovery of copper-nickel deposits, a new apatite alkaline massif, promising manifestation of copper-nickel ore, platinum group metals, native gold, chromite and other mineral resources. A thorough drilling of ice sheets in Greenland and Antarctica for the international project determined the absence of boulder material over the entire thickness of the ice, only pulverulent and fine particles (mainly volcanic ash were found in the ice. Bottom ice layers are immobilised, their function is preservation of the geological surface. V. G. Chuvardinsky far outstripped western and Russian scientists in the field of Earth Sciences. His field studies on the Baltic Shield not only refuted the mighty glacial theory, but also created and substantiated a new geological concept instead. Professor V. Z. Negrutsa was quite right when he wrote in his review on Chuvardinsky’s work (journal Geomorfologiya, 2003, no. 1, ‘Evidence of Chuvardinsky about tectonic origin of geological and geomorphological features traditionally associated with the Quaternary glaciation is so obvious and reproducible both by field observations and by geological modeling that is presented irrefutable and undeniable in its essence’. In general, assessing the scientific significance of V. G. Chuvardinsky’s works, it can be stated that his work would have done honour to research institutes of geological and geographical orientation according to the level of study of the geological material and the value of his field studies. His books present the material for

General relativity and mathematics; Relatividad General y Matematicas

Energy Technology Data Exchange (ETDEWEB)

Mars, M.

2015-07-01

General relativity is more than a theory of gravity, since any physical process occupies space and lasts for a time, forcing to reconcile that physical theory that describes what the dynamic nature of space-time itself. (Author)

Overview and theory relating to the concepts of competitiveness, efficiency and productivity

OpenAIRE

Latruffe, Laure

2017-01-01

This is a brief overview and theory relating to the concepts of competitiveness, efficiency and productivity: concept of competitiveness, measurement of competitiveness, determinants of competitiveness.

Conformal covariance of general relativity

International Nuclear Information System (INIS)

Ionescu-Pallas, N.; Gottlieb, I.

1980-01-01

The Einstein's equations of General Relativity are written in a conformal metric, resulting as a consequence of geometrizing the pressure forces. Accordingly, the trajectory of a test body pursues a geodetic line even inside the source of gravitational field. Moreover, the pressure, entering the perfect fluid scheme, may be replaced by a certain scalar interaction. This new manner of interpreting General Relativity is then applied to Cosmology, in order to build up a model of Universe whose static limit should coincide with that of Einstein. At the same time, the cosmological constant is connected to the scalar interaction acquiring a plausible explanation. (author)

General concept of a gas engine for a hybrid vehicle, operating on methanol dissociation products

International Nuclear Information System (INIS)

Tartakovsky, L.; Aleinikov, Y.; Fainberg, V.; Garbar, A.; Gutman, M.; Hetsroni, G.; Schindler, Y.; Zvirin, Y.

1998-01-01

The paper presents a general concept of a hybrid propulsion system, based on an SI internal combustion engine fueled by methanol dissociation products (MDP). The proposed hybrid propulsion scheme is a series hybrid, which allows the engine to be operated in an on-off mode at constant optimal regime. The engine is fed by gaseous products of methanol dissociation (mainly hydrogen and carbon monoxide) emerging from an on-board catalytic reformer. The general scheme and base operation features of the propulsion system are described. The benefits that may be achieved by combining the well-known idea of on-board methanol dissociation with the hybrid vehicle concept are discussed. The proposed scheme is compared with those of systems operating on gasoline, liquid methanol, hydrogen and also with the multi-regime (not hybrid) engine fed by MDP

Black hole based tests of general relativity

International Nuclear Information System (INIS)

Yagi, Kent; Stein, Leo C

2016-01-01

General relativity has passed all solar system experiments and neutron star based tests, such as binary pulsar observations, with flying colors. A more exotic arena for testing general relativity is in systems that contain one or more black holes. Black holes are the most compact objects in the Universe, providing probes of the strongest-possible gravitational fields. We are motivated to study strong-field gravity since many theories give large deviations from general relativity only at large field strengths, while recovering the weak-field behavior. In this article, we review how one can probe general relativity and various alternative theories of gravity by using electromagnetic waves from a black hole with an accretion disk, and gravitational waves from black hole binaries. We first review model-independent ways of testing gravity with electromagnetic/gravitational waves from a black hole system. We then focus on selected examples of theories that extend general relativity in rather simple ways. Some important characteristics of general relativity include (but are not limited to) (i) only tensor gravitational degrees of freedom, (ii) the graviton is massless, (iii) no quadratic or higher curvatures in the action, and (iv) the theory is four-dimensional. Altering a characteristic leads to a different extension of general relativity: (i) scalar–tensor theories, (ii) massive gravity theories, (iii) quadratic gravity, and (iv) theories with large extra dimensions. Within each theory, we describe black hole solutions, their properties, and current and projected constraints on each theory using black hole based tests of gravity. We close this review by listing some of the open problems in model-independent tests and within each specific theory. (paper)

The Confrontation between General Relativity and Experiment

Directory of Open Access Journals (Sweden)

Will Clifford

2001-01-01

Full Text Available The status of experimental tests of general relativity and of theoretical frameworks for analysing them are reviewed. Einstein's equivalence principle (EEP is well supported by experiments such as the Eötvös experiment, tests of special relativity, and the gravitational redshift experiment. Future tests of EEP and of the inverse square law will search for new interactions arising from unification or quantum gravity. Tests of general relativity at the post-Newtonian level have reached high precision, including the light deflection, the Shapiro time delay, the perihelion advance of Mercury, and the Nordtvedt effect in lunar motion. Gravitational wave damping has been detected in an amount that agrees with general relativity to half a percent using the Hulse-Taylor binary pulsar, and new binary pulsar systems may yield further improvements.When direct observation of gravitational radiation from astrophysical sources begins, new tests of general relativity will be possible.

Judeo-Christian concepts related to psychiatry

Science.gov (United States)

Ponnudurai, R.

2013-01-01

The behavioral manifestations of psychotic disorders that are attributed to evil spirits in the Judeo-Christian scriptures as demonstrated by Jesus Christ have been narrated. The descriptions of false beliefs and the perceptual experiences that are consistent with the psychiatric terminologies “delusions and hallucinations” are briefly discussed. Attempt has been made to analyze the patterns of suicidal behaviors, guilt feelings, and, expressions of depressive symptoms in the Jewish culture. Of interest is the mass suicide by the Jews in the 1st century AD at the Fort Masada, perhaps the first of its kind recorded in the history. Noteworthy are alcohol and related mental health problems prevalent in the Jewish culture. While highlighting the descriptions of dreams and their revelations recorded in the Bible, it is suggested that such concepts about dreams might have influenced Sigmund Freud's classical works on dreams. The biblical messages and teachings that could be applied for psychotherapy and behavior modification strategies have been outlined. The mental concepts of Jewish culture and their relevance to Indian culture have also been discussed from a cross-cultural perspective. PMID:23858255

Formal structures, the concepts of covariance, invariance, equivalent reference frames, and the principle Relativity

Science.gov (United States)

Rodrigues, W. A.; Scanavini, M. E. F.; de Alcantara, L. P.

1990-02-01

In this paper a given spacetime theory T is characterized as the theory of a certain species of structure in the sense of Bourbaki [1]. It is then possible to clarify in a rigorous way the concepts of passive and active covariance of T under the action of the manifold mapping group G M . For each T, we define also an invariance group G I T and, in general, G I T ≠ G M . This group is defined once we realize that, for each τ ∈ ModT, each explicit geometrical object defining the structure can be classified as absolute or dynamical [2]. All spacetime theories possess also implicit geometrical objects that do not appear explicitly in the structure. These implicit objects are not absolute nor dynamical. Among them there are the reference frame fields, i.e., “timelike” vector fields X ∈ TU,U subseteq M M, where M is a manifold which is part of ST, a substructure for each τ ∈ ModT, called spacetime. We give a physically motivated definition of equivalent reference frames and introduce the concept of the equivalence group of a class of reference frames of kind X according to T, G X T. We define that T admits a weak principle of relativity (WPR) only if G X T ≠ identity for some X. If G X T = G I T for some X, we say that T admits a strong principle of relativity (PR). The results of this paper generalize and clarify several results obtained by Anderson [2], Scheibe [3], Hiskes [4], Recami and Rodrigues [5], Friedman [6], Fock [7], and Scanavini [8]. Among the novelties here, there is the realization that the definitions of G I T and G X T can be given only when certain boundary conditions for the equations of motion of T can be physically realizable in the domain U U subseteq M M, where a given reference frame is defined. The existence of physically realizable boundary conditions for each τ ∈ ModT (in ∂ U), in contrast with the mathematically possible boundary condition, is then seen to be essential for the validity of a principle of relativity for T

Mathematica® for Theoretical Physics Electrodynamics, Quantum Mechanics, General Relativity and Fractals

CERN Document Server

Baumann, Gerd

2005-01-01

Mathematica for Theoretical Physics: Electrodynamics, Quantum Mechanics, General Relativity, and Fractals This second edition of Baumann's Mathematica® in Theoretical Physics shows readers how to solve physical problems and deal with their underlying theoretical concepts while using Mathematica® to derive numeric and symbolic solutions. Each example and calculation can be evaluated by the reader, and the reader can change the example calculations and adopt the given code to related or similar problems. The second edition has been completely revised and expanded into two volumes: The first volume covers classical mechanics and nonlinear dynamics. Both topics are the basis of a regular mechanics course. The second volume covers electrodynamics, quantum mechanics, relativity, and fractals and fractional calculus. New examples have been added and the representation has been reworked to provide a more interactive problem-solving presentation. This book can be used as a textbook or as a reference work, by student...

The speed of gravity in general relativity and theoretical interpretation of the Jovian deflection experiment

International Nuclear Information System (INIS)

Kopeikin, Sergei M

2004-01-01

According to Einstein, the notions of geodesic, parallel transport (affine connection) and curvature of the spacetime manifold have a pure geometric origin and do not correlate with any electromagnetic concepts. At the same time, curvature is generated by matter which is not affiliated with the spacetime geometric concepts. For this reason, the fundamental constant c entering the geometric and matter sectors of the general theory of relativity has different conceptual meanings. Specifically, the letter c on the left-hand side of the Einstein equations (geometric sector) entering the Christoffel symbols and its time derivatives is the ultimate speed of gravity characterizing the upper limit on the speed of its propagation as well as the maximal rate of change of time derivatives of the metric tensor, that is gravitational field. The letter c on the right-hand side of the Einstein equations (matter sector) is the maximal speed of propagation of any other field rather than gravity. Einstein's general principle of relativity extends his principle of special relativity and equates the numerical value of the ultimate speed of gravity to that of the speed of light in the special theory of relativity but this general principle must be tested experimentally. To this end, we work out the speed of gravity parametrization of the Einstein equations (c g -parametrization) to keep track of the time-dependent effects associated with the geometric sector of general relativity and to separate them from the time-dependent effects of the matter sector. Parametrized post-Newtonian (PPN) approximation of the Einstein equations is derived in order to explain the gravitational physics of the Jovian deflection VLBI experiment conducted on 8 September 2002. The post-Newtonian series expansion in the c g -parametrized general relativity is with respect to a small parameter that is proportional to the ratio of the characteristic velocity of the bodies to the speed of propagation of the

Preservice Teachers' Professional Knowledge and Its Relation to Academic Self-Concept

Science.gov (United States)

Paulick, Isabell; Großschedl, Jörg; Harms, Ute; Möller, Jens

2016-01-01

We investigated the factorial structure of preservice teachers' academic self-concept with regard to three domains of professional knowledge (content knowledge [CK], pedagogical content knowledge [PCK], and pedagogical/psychological knowledge [PPK]). We also analyzed the relation between preservice teachers' academic self-concept and their…

The Confrontation between General Relativity and Experiment

Directory of Open Access Journals (Sweden)

Will Clifford M.

2006-03-01

Full Text Available The status of experimental tests of general relativity and of theoretical frameworks for analyzing them is reviewed. Einstein’s equivalence principle (EEP is well supported by experiments such as the Eötvös experiment, tests of special relativity, and the gravitational redshift experiment. Ongoing tests of EEP and of the inverse square law are searching for new interactions arising from unification or quantum gravity. Tests of general relativity at the post-Newtonian level have reached high precision, including the light deflection, the Shapiro time delay, the perihelion advance of Mercury, and the Nordtvedt effect in lunar motion. Gravitational wave damping has been detected in an amount that agrees with general relativity to better than half a percent using the Hulse-Taylor binary pulsar, and other binary pulsar systems have yielded other tests, especially of strong-field effects. When direct observation of gravitational radiation from astrophysical sources begins, new tests of general relativity will be possible.

The gauge in general relativity

International Nuclear Information System (INIS)

Cohn, J.

1975-01-01

The view is taken that the field equations of General Relativity, without a definition of congruence of length and time intervals at different events, are without physical content. The possibility is explored that the customary Einstein field equations are to be used but with a different congruence definition than is customary. When these resulting equations are, in turn, expressed with the customary congruence, they comprise a new set of field equations physically not equivalent to either Einstein's or Brans-Dicke's formulations of general relativity. Similarities with Einstein's and Brans-Dicke's formulations are discussed, and the possibility of experimental confirmation of these new equations is also briefly considered. (author)

Ducklings imprint on the relational concept of "same or different".

Science.gov (United States)

Martinho, Antone; Kacelnik, Alex

2016-07-15

The ability to identify and retain logical relations between stimuli and apply them to novel stimuli is known as relational concept learning. This has been demonstrated in a few animal species after extensive reinforcement training, and it reveals the brain's ability to deal with abstract properties. Here we describe relational concept learning in newborn ducklings without reinforced training. Newly hatched domesticated mallards that were briefly exposed to a pair of objects that were either the same or different in shape or color later preferred to follow pairs of new objects exhibiting the imprinted relation. Thus, even in a seemingly rigid and very rapid form of learning such as filial imprinting, the brain operates with abstract conceptual reasoning, a faculty often assumed to be reserved to highly intelligent organisms. Copyright © 2016, American Association for the Advancement of Science.

Distributing learning over time: the spacing effect in children's acquisition and generalization of science concepts.

Science.gov (United States)

Vlach, Haley A; Sandhofer, Catherine M

2012-01-01

The spacing effect describes the robust finding that long-term learning is promoted when learning events are spaced out in time rather than presented in immediate succession. Studies of the spacing effect have focused on memory processes rather than for other types of learning, such as the acquisition and generalization of new concepts. In this study, early elementary school children (5- to 7-year-olds; N = 36) were presented with science lessons on 1 of 3 schedules: massed, clumped, and spaced. The results revealed that spacing lessons out in time resulted in higher generalization performance for both simple and complex concepts. Spaced learning schedules promote several types of learning, strengthening the implications of the spacing effect for educational practices and curriculum. © 2012 The Authors. Child Development © 2012 Society for Research in Child Development, Inc.

Quantum mechanics from general relativity

International Nuclear Information System (INIS)

Sachs, M.

1986-01-01

A generalization of quantum mechanics is demonstrated in the context of general relativity, following from a generally covariant field theory of inertia. Nonrelativistically, the formalism corresponds with linear quantum mechanics. In the limit of special relativity, nonlinearity remains and several new features are derived: (1) Particle-antiparticle pairs do not annihilate; an exact bound state solution is derived corresponding with all experimental facts about annihilation/creation - which, in approximation, gives the blackbody radiation spectrum for a sea of such pairs. (2) A result is proven, without approximation, that is physically equivalent to the Pauli exclusion principle - which, in linear approximation, gives the totally antisymmetrised many-body wave function and Fermi-Dirac statistics. (3) The hydrogen spectrum is derived, including the Lamb shifts, in agreement with experiment; new results are found for high energy electron-proton scattering. (4) Finally, several applications to the elementary particle domain are demonstrated, in agreement with results from experimental high energy physics. (Auth.)

Are digital games perceived as fun or danger? Supporting and suppressing different game-related concepts.

Science.gov (United States)

Kneer, Julia; Glock, Sabine; Beskes, Sara; Bente, Gary

2012-11-01

Violent digital game play has repeatedly been discussed to be strongly related to aggression and emotional instability. Thus, digital game players have to defend against these prejudices through emphasizing positive game-related concepts such as achievement, social interaction, and immersion. We experimentally investigated which positive- and negative-concept players and nonplayers activate when being primed with digital games. Participants were either exposed to violent or nonviolent game content and were required to work on a lexical decision task. Results showed that response latencies for the concept aggression and emotional instability were faster than for neutral concepts (not associated with digital games), but slower than for the positive concepts sociality and competition. Both players and nonplayers felt the need to defend against prejudices and emphasized positive concepts. Neither their own gaming experience nor the game content influenced the results. Being a part of the net generation is sufficient to suppress negative game-related concepts and to support positive game-related concepts to protect digital games as common leisure activity among peers.

ABOUT THE GENERAL CONCEPT OF THE UNIVERSAL STORAGE SYSTEM AND PRACTICE-ORIENTED DATA PROCESSING

Directory of Open Access Journals (Sweden)

L. V. Rudikova

2017-01-01

Full Text Available Approaches evolution and concept of data accumulation in warehouse and subsequent Data Mining use is perspective due to the fact that, Belarusian segment of the same IT-developments is organizing. The article describes the general concept for creation a system of storage and practice-oriented data analysis, based on the data warehousing technology. The main aspect in universal system design on storage layer and working with data is approach uses extended data warehouse, based on universal platform of stored data, which grants access to storage and subsequent data analysis different structure and subject domains have compound’s points (nodes and extended functional with data structure choice option for data storage and subsequent intrasystem integration. Describe the universal system general architecture of storage and analysis practice-oriented data, structural elements. Main components of universal system for storage and processing practice-oriented data are: online data sources, ETL-process, data warehouse, subsystem of analysis, users. An important place in the system is analytical processing of data, information search, document’s storage and providing a software interface for accessing the functionality of the system from the outside. An universal system based on describing concept will allow collection information of different subject domains, get analytical summaries, do data processing and apply appropriate Data Mining methods and algorithms.

Towards a Definition of Role-related Concepts for Business Modeling

NARCIS (Netherlands)

Meertens, Lucas Onno; Iacob, Maria Eugenia; Nieuwenhuis, Lambertus Johannes Maria

2010-01-01

Abstract—While several role-related concepts play an important role in business modeling, their definitions, relations, and use differ greatly between languages, papers, and reports. Due to this, the knowledge captured by models is not transferred correctly, and models are incomparable. In this

Dissociating the Representation of Action- and Sound-Related Concepts in Middle Temporal Cortex

Science.gov (United States)

Kiefer, Markus; Trumpp, Natalie; Herrnberger, Barbel; Sim, Eun-Jin; Hoenig, Klaus; Pulvermuller, Friedemann

2012-01-01

Modality-specific models of conceptual memory propose close links between concepts and the sensory-motor systems. Neuroimaging studies found, in different subject groups, that action-related and sound-related concepts activated different parts of posterior middle temporal gyrus (pMTG), suggesting a modality-specific representation of conceptual…

Special relativity, electrodynamics, and general relativity from Newton to Einstein

CERN Document Server

Kogut, John B

2018-01-01

Special Relativity, Electrodynamics and General Relativity: From Newton to Einstein, Second Edition, is intended to teach (astro)physics, astronomy, and cosmology students how to think about special and general relativity in a fundamental, but accessible, way. Designed to render any reader a "master of relativity," everything on the subject is comprehensible and derivable from first principles. The book emphasizes problem solving, contains abundant problem sets, and is conveniently organized to meet the needs of both student and instructor. Fully revised, updated and expanded second edition Includes new chapters on magnetism as a consequence of relativity and electromagnetism Contains many improved and more engaging figures Uses less algebra resulting in more efficient derivations Enlarged discussion of dynamics and the relativistic version of Newton's second law

Modern Canonical Quantum General Relativity

Science.gov (United States)

Thiemann, Thomas

2008-11-01

Preface; Notation and conventions; Introduction; Part I. Classical Foundations, Interpretation and the Canonical Quantisation Programme: 1. Classical Hamiltonian formulation of general relativity; 2. The problem of time, locality and the interpretation of quantum mechanics; 3. The programme of canonical quantisation; 4. The new canonical variables of Ashtekar for general relativity; Part II. Foundations of Modern Canonical Quantum General Relativity: 5. Introduction; 6. Step I: the holonomy-flux algebra [P]; 7. Step II: quantum-algebra; 8. Step III: representation theory of [A]; 9. Step IV: 1. Implementation and solution of the kinematical constraints; 10. Step V: 2. Implementation and solution of the Hamiltonian constraint; 11. Step VI: semiclassical analysis; Part III. Physical Applications: 12. Extension to standard matter; 13. Kinematical geometrical operators; 14. Spin foam models; 15. Quantum black hole physics; 16. Applications to particle physics and quantum cosmology; 17. Loop quantum gravity phenomenology; Part IV. Mathematical Tools and their Connection to Physics: 18. Tools from general topology; 19. Differential, Riemannian, symplectic and complex geometry; 20. Semianalytical category; 21. Elements of fibre bundle theory; 22. Holonomies on non-trivial fibre bundles; 23. Geometric quantisation; 24. The Dirac algorithm for field theories with constraints; 25. Tools from measure theory; 26. Elementary introduction to Gel'fand theory for Abelean C* algebras; 27. Bohr compactification of the real line; 28. Operatir -algebras and spectral theorem; 29. Refined algebraic quantisation (RAQ) and direct integral decomposition (DID); 30. Basics of harmonic analysis on compact Lie groups; 31. Spin network functions for SU(2); 32. + Functional analytical description of classical connection dynamics; Bibliography; Index.

First-Year Cadets' Conceptions of General Education Writing at a Senior Military College

Science.gov (United States)

Rifenburg, J. Michael; Forester, Brian

2018-01-01

This study investigates conceptions first-year cadets at a US senior military college bring to general education writing courses, often termed first-year composition (FYC). Using a mixed methods research design, we received survey responses from 122 cadets and conducted semi-structured in-person interviews with four first-year cadets. Our data…

Intuitionistic fuzzy 2-normed space and some related concepts

International Nuclear Information System (INIS)

Mursaleen, M.; Danish Lohani, Q.M.

2009-01-01

Motivated by the notion of 2-norm due to Gaehler [Gaehler S. Lineare 2-normietre Raeume. Math Nachr 28;1965:1-43], in this paper we define the concept of intuitionistic fuzzy 2-normed space which is a generalization of the notion of intuitionistic fuzzy normed space due to Saadati and Park [Saadati R, Park JH, On the intuitionistic fuzzy topological spaces. Chaos Solitons and Fractals 2006;27:331-44]. Further we establish some topological results in this new set up.

Preservice Elementary Mathematics Teachers' Level of Relating Mathematical Concepts in Daily Life Contexts

Science.gov (United States)

Akkus, Oylum

2008-01-01

The purpose of this study was to investigate preservice elementary mathematics teachers' ability of relating mathematical concepts and daily life context. Two research questions were set; what is the preservice elementary mathematics teachers' level of relating mathematical concepts and daily life context regarding to their education year and…

Advancing Uncertainty: Untangling and Discerning Related Concepts

Directory of Open Access Journals (Sweden)

Janice Penrod

2002-12-01

Full Text Available Methods of advancing concepts within the qualitative paradigm have been developed and articulated. In this section, I describe methodological perspectives of a project designed to advance the concept of uncertainty using multiple qualitative methods. Through a series of earlier studies, the concept of uncertainty arose repeatedly in varied contexts, working its way into prominence, and warranting further investigation. Processes of advanced concept analysis were used to initiate the formal investigation into the meaning of the concept. Through concept analysis, the concept was deconstructed to identify conceptual components and gaps in understanding. Using this skeletal framework of the concept identified through concept analysis, subsequent studies were carried out to add ‘flesh’ to the concept. First, a concept refinement using the literature as data was completed. Findings revealed that the current state of the concept of uncertainty failed to incorporate what was known of the lived experience. Therefore, using interview techniques as the primary data source, a phenomenological study of uncertainty among caregivers was conducted. Incorporating the findings of the phenomenology, the skeletal framework of the concept was further fleshed out using techniques of concept correction to produce a more mature conceptualization of uncertainty. In this section, I describe the flow of this qualitative project investigating the concept of uncertainty, with special emphasis on a particular threat to validity (called conceptual tunnel vision that was identified and addressed during the phases of concept correction. Though in this article I employ a study of uncertainty for illustration, limited substantive findings regarding uncertainty are presented to retain a clear focus on the methodological issues.

Einstein and the history of general relativity

International Nuclear Information System (INIS)

Howard, D.; Stachel, J.

1989-01-01

This book is a collection of essays by the authors and other people that deal with scientific opinions that led Einstein and his contemporaries to their views of general relativity. Some of the essays explore Einstein's passage from the special theory through a sequence of gravitational theories to the discovery of the field equations of the grand theory in November 1915. Two other essays discuss Einstein's public and private exchanges with Max Abraham and Tullio Levi-Civita in 1913 and 1914. A sympathetic picture of H.A. Lorentz's reaction to the general theory of relativity is included, and a careful and insightful essay on the early understanding of the Schwarzschild-Droste solution to the field equations of general relativity is presented. One paper presents a discussion on the state of the enterprise of general relativity between 1925 and 1928, and a short essay details the history of steps toward quantum gravitational through canonical quantization. A discussion of the history of derivations of the geodesic equation of motion from the field equation and conservation laws of the general theory is presented. The early history of geometrical unified field theories is included

Relational Coordination in Danish General Practice

DEFF Research Database (Denmark)

Lundstrøm, Sanne Lykke

. The dissertation present the research study and a collection of three research papers prepared during the period from May 2010 to June 2014. Relational coordination and organisational social capital are measures of novel aspects of an organisation's performance. Relational coordination analyse the communication...... and relationship networks through which work is coordinated across functional and organisational boundaries. Previous studies have shown that relational coordination is positively associated with delivery of care for patients with chronic illness. Organisational social capital is used when analysing...... the psychosocial work environment in organisations, and is seen as a powerful resources for improving organisational performance. Relational coordination and organisational social capital may oer new insight and opportunities for general practice to learn. General practice provides cost-efficient, first...

Comment on "Ducklings imprint on the relational concept of 'same or different'".

Science.gov (United States)

Langbein, Jan; Puppe, Birger

2017-02-24

Martinho and Kacelnik (Reports, 15 July 2016, p. 286) reported that newly hatched ducklings imprinted on relational concepts. We argue that reanalyzing the data at the individual level shows that this conclusion cannot be applied for all sets of stimuli presented and that the ability to grasp relational concepts is limited to the stimulus category that is most beneficial for survival. Copyright © 2017, American Association for the Advancement of Science.

Generalized Schmidt decomposability and its relation to projective norms in multipartite entanglement

International Nuclear Information System (INIS)

Sokoli, Florian; Alber, Gernot

2014-01-01

Projective norms are capable of measuring entanglement of multipartite quantum states. However, typically, the explicit computation of these distance-based geometric entanglement monotones is very difficult even for finite dimensional systems. Motivated by the significance of Schmidt decompositions for our quantitative understanding of bipartite quantum entanglement, a generalization of this concept to multipartite scenarios is proposed, in the sense that generalized Schmidt decomposability of a multipartite pure state implies that its projective norm can be calculated in a simple way analogous to the bipartite case. Thus, this concept of generalized Schmidt decomposability of multipartite quantum states is linked in a natural way to projective norms as entanglement monotones. Therefore, it may not only be a convenient tool for calculations, but may also shed new light onto the intricate features of multipartite entanglement in an analogous way as the ‘classical’ Schmidt decomposition does for bipartite quantum systems. (paper)

The genesis of general relativity

CERN Document Server

Norton, John; Renn, Jürgen; Sauer, Tilman; Stachel, John

2007-01-01

This four-volume work represents the most comprehensive documentation and study of the creation of general relativity; one of the fundamental physical theories of the 20th century. It comprises key sources from Einstein and others who from the late 19th to the early 20th century contributed to this monumental development. Some of these sources are presented here in translation for the first time. Einstein’s famous Zurich notebook, which documents the pivotal steps toward general relativity, is reproduced here for the first time and transcribed in its entirety. The volumes offer detailed commentaries and analyses of these sources that are based on a close reading of these documents supplemented by interpretations by the leading historians of relativity. All in all, the facets of this work, based on more than a decade of research, combine to constitute one of the most in-depth studies of a scientific revolution ever written.

Differential forms and the geometry of general relativity

CERN Document Server

Dray, Tevian

2015-01-01

Differential Forms and the Geometry of General Relativity provides readers with a coherent path to understanding relativity. Requiring little more than calculus and some linear algebra, it helps readers learn just enough differential geometry to grasp the basics of general relativity.The book contains two intertwined but distinct halves. Designed for advanced undergraduate or beginning graduate students in mathematics or physics, most of the text requires little more than familiarity with calculus and linear algebra. The first half presents an introduction to general relativity that describes

Age and gender differences in the relation between self-concept facets and self-esteem

OpenAIRE

Arens, A. Katrin; Hasselhorn, Marcus

2014-01-01

This study tested whether the gender intensification hypothesis applies to relations between multiple domain-specific self-concept facets and self-esteem. This hypothesis predicts gender-stereotypic differences in these relations and assumes they intensify with age. Furthermore, knowledge about gender-related or age-related differences in self-concept-self-esteem relations might provide valuable knowledge for designing effective self-esteem enhancement interventions. We investigated grade and...

Generalized Moshinsky bracket recurrence relations

International Nuclear Information System (INIS)

Bevelacqua, J.J.

1979-01-01

Recurrence relations for generalized Talmi-Moshinsky brackets are derived. These relations permit the generation of transformation brackets once appropriate starting brackets are determined. The savings in computer time, when compared with generating brackets individually, is at least a factor of 10 for brackets with radial quantum numbers as large as 9 and angular quantum numbers as large as 2. (author)

The future of general classification

DEFF Research Database (Denmark)

Mai, Jens Erik

2013-01-01

Discusses problems related to accessing multiple collections using a single retrieval language. Surveys the concepts of interoperability and switching language. Finds that mapping between more indexing languages always will be an approximation. Surveys the issues related to general classification...... and contrasts that to special classifications. Argues for the use of general classifications to provide access to collections nationally and internationally....

Geometrical optics in general relativity

OpenAIRE

Loinger, A.

2006-01-01

General relativity includes geometrical optics. This basic fact has relevant consequences that concern the physical meaning of the discontinuity surfaces propagated in the gravitational field - as it was first emphasized by Levi-Civita.

An Introduction to General Relativity and Cosmology

International Nuclear Information System (INIS)

Wainwright, John

2007-01-01

inflation scenario, arguing that the problems that it aims to solve (the so-called horizon problem and the flatness problem) are a consequence of the very special geometry of the FL models. In particular, the flatness problem loses its urgency when one broadens the class of cosmological models, since the condition for flatness depends on spatial position. They also discuss in detail an analysis due to Celerier and Schneider showing how the horizon problem can be resolved using a delayed big-bang singularity in a Lemaitre-Tolman cosmology. We comment on two notable omissions as regards cosmology. First, the authors only refer in passing to the notion of the density parameter, which plays an important role in the analysis of the FL models, and which can also be introduced in more general models. Second, there is no discussion of perturbations of the FL models, although two related concepts, the density contrast and the curvature contrast, are analysed in the Lemaitre-Tolman models. A second unusual feature is that there is a considerable emphasis on exact solutions, their derivation and physical interpretation. Derivations that are given in detail are for the spatially homogeneous solution of Bianchi type I with pressure-free matter, the Lemaitre-Tolman solutions, the Szekeres solutions and the Kerr solution (the original derivation using the Kerr-Schild metric, and Carter's derivation using separability of the Klein-Gordon equation). Readers may wish to compare the above-mentioned derivation of the Bianchi type I solutions, which uses metric components and coordinates, with the derivation given, using the orthonormal frame formalism. In summary, this book is an interesting and informative introduction to general relativity and cosmology. The unconventional choice of topics and emphasis may, however, lead some readers to conclude that it may be more suitable as a reference work than as the text for a course. (book review)

Gravity: An Introduction to Einstein's General Relativity

International Nuclear Information System (INIS)

Fabris, Julio C

2004-01-01

General relativity is one of the cornerstones of modern physics. In spite of this, the teaching of general relativity at undergraduate level remains quite marginal. The reasons for this particular situation are quite well known. We can quote, for example, two of them: general relativity requires specific mathematical tools that are somehow outside the mainstream of undergraduate technical development; moreover, this is a branch of physics whose observational and experimental applications have remained rare until recent times, and even though this scenario has changed dramatically in the last few years, the new situation has not yet been absorbed into undergraduate teaching. In this new book, Hartle attempts to address the difficulties that must be faced by anyone who teaches general relativity at undergraduate level. In order to not scare the student with the hard technical preparation needed to obtain the basic equations of general relativity, Einstein's equations, he simply gives up the idea of introducing these equations at the very beginning. Instead, he chooses to present Einstein's equations, with most of the mathematics needed to do them, in the last part of the book. This delicate (and of course dangerous) choice has the advantage of introducing the reader first to the physical aspects of general relativity. This approach can be dangerous because the relevant solutions of the equations necessary to discuss the physical content of general relativity are presented first without a formal derivation. The book is divided into three parts. In the first, covering five chapters of the 24 in the whole book, Newtonian physics and special relativity are reviewed. This review is done in a manner that prepares the reader for the subsequent discussion of general relativity itself. The principle of relativity, the variational principle, the geometrical content of Newtonian theory and the main ideas behind special relativity are all presented. The heart of the book is, in

A generalized Principle of Relativity

International Nuclear Information System (INIS)

Felice, Fernando de; Preti, Giovanni

2009-01-01

The Theory of Relativity stands as a firm groundstone on which modern physics is founded. In this paper we bring to light an hitherto undisclosed richness of this theory, namely its admitting a consistent reformulation which is able to provide a unified scenario for all kinds of particles, be they lightlike or not. This result hinges on a generalized Principle of Relativity which is intrinsic to Einstein's theory - a fact which went completely unnoticed before. The road leading to this generalization starts, in the very spirit of Relativity, from enhancing full equivalence between the four spacetime directions by requiring full equivalence between the motions along these four spacetime directions as well. So far, no measurable spatial velocity in the direction of the time axis has ever been defined, on the same footing of the usual velocities - the 'space-velocities' - in the local three-space of a given observer. In this paper, we show how Relativity allows such a 'time-velocity' to be defined in a very natural way, for any particle and in any reference frame. As a consequence of this natural definition, it also follows that the time- and space-velocity vectors sum up to define a spacelike 'world-velocity' vector, the modulus of which - the world-velocity - turns out to be equal to the Maxwell's constant c, irrespective of the observer who measures it. This measurable world-velocity (not to be confused with the space-velocities we are used to deal with) therefore represents the speed at which all kinds of particles move in spacetime, according to any observer. As remarked above, the unifying scenario thus emerging is intrinsic to Einstein's Theory; it extends the role traditionally assigned to Maxwell's constant c, and can therefore justly be referred to as 'a generalized Principle of Relativity'.

The consistency assessment of topological relations in cartographic generalization

Science.gov (United States)

Zheng, Chunyan; Guo, Qingsheng; Du, Xiaochu

2006-10-01

The field of research in the generalization assessment has been less studied than the generalization process itself, and it is very important to keep topological relation consistency for meeting generalization quality. This paper proposes a methodology to assess the quality of generalized map from topological relations consistency. Taking roads (including railway) and residential areas for examples, from the viewpoint of the spatial cognition, some issues about topological consistency in different map scales are analyzed. The statistic information about the inconsistent topological relations can be obtained by comparing the two matrices: one is the matrix for the topological relations in the generalized map; the other is the theoretical matrix for the topological relations that should be maintained after generalization. Based on the fuzzy set theory and the classification of map object types, the consistency evaluation model of topological relations is established. The paper proves the feasibility of the method through the example about how to evaluate the local topological relations between simple roads and residential area finally.

Comparative phylogeography: concepts, methods and general patterns in neotropical birds

International Nuclear Information System (INIS)

Arbelaez Cortes, Enrique

2012-01-01

Understanding the patterns and processes involved in intraspecific lineages diversification in time and space is the aim of phylogeography. The comparison of those phylogeographic patterns among co-distributed species shows insights of a community history. Here I review the concepts and methodologies of comparative phylogeography, an active research field that has heterogeneous analytical methods. In order to present a framework for phylogeography in the neotropics, I comment the general phylogeographic patterns of the birds from this region. this review is based on more than 100 studies conducted during the last 25 years and indicate that despite different co-distributed species seem to share some points in their phylogeographic pattern they have idiosyncratic aspects, indicating an unique history for each one.

Auditing SNOMED CT hierarchical relations based on lexical features of concepts in non-lattice subgraphs.

Science.gov (United States)

Cui, Licong; Bodenreider, Olivier; Shi, Jay; Zhang, Guo-Qiang

2018-02-01

We introduce a structural-lexical approach for auditing SNOMED CT using a combination of non-lattice subgraphs of the underlying hierarchical relations and enriched lexical attributes of fully specified concept names. Our goal is to develop a scalable and effective approach that automatically identifies missing hierarchical IS-A relations. Our approach involves 3 stages. In stage 1, all non-lattice subgraphs of SNOMED CT's IS-A hierarchical relations are extracted. In stage 2, lexical attributes of fully-specified concept names in such non-lattice subgraphs are extracted. For each concept in a non-lattice subgraph, we enrich its set of attributes with attributes from its ancestor concepts within the non-lattice subgraph. In stage 3, subset inclusion relations between the lexical attribute sets of each pair of concepts in each non-lattice subgraph are compared to existing IS-A relations in SNOMED CT. For concept pairs within each non-lattice subgraph, if a subset relation is identified but an IS-A relation is not present in SNOMED CT IS-A transitive closure, then a missing IS-A relation is reported. The September 2017 release of SNOMED CT (US edition) was used in this investigation. A total of 14,380 non-lattice subgraphs were extracted, from which we suggested a total of 41,357 missing IS-A relations. For evaluation purposes, 200 non-lattice subgraphs were randomly selected from 996 smaller subgraphs (of size 4, 5, or 6) within the "Clinical Finding" and "Procedure" sub-hierarchies. Two domain experts confirmed 185 (among 223) suggested missing IS-A relations, a precision of 82.96%. Our results demonstrate that analyzing the lexical features of concepts in non-lattice subgraphs is an effective approach for auditing SNOMED CT. Copyright © 2017 Elsevier Inc. All rights reserved.

General relativity and gravitation, 1989

International Nuclear Information System (INIS)

Ashby, N.; Bartlett, D.F.; Wyss, W.

1990-01-01

This volume records the lectures and symposia of the 12th International Conference on General Relativity and Gravitation. Plenary lecturers reviewed the major advances since the previous conference in 1986. The reviews cover classical and quantum theory of gravity, colliding gravitational waves, gravitational lensing, relativistic effects on pulsars, tests of the inverse square law, numerical relativity, cosmic microwave background radiation, experimental tests of gravity theory, gravitational wave detectors, and cosmology. The plenary lectures are complemented by summaries of symposia, provided by the chairmen. Almost 700 contributed papers were presented at these and they cover an even wider range of topics than the plenary talks. The book provides a comprehensive guide to research activity in both experimental and theoretical gravitation and its applications in astrophysics and cosmology. It will be essential reading for research workers in these fields, as well as theoretical and experimental physicists, astronomers, and mathematicians who wish to be acquainted with modern developments in gravitational theory and general relativity. All the papers and summaries of the workshop sessions are indexed separately. (16 united talks, 20 workshop sessions). (author)

Self-concept mediates the relation between achievement and emotions in mathematics

NARCIS (Netherlands)

Van der Beek, Jojanneke P J; Van der Ven, Sanne H G; Kroesbergen, Evelyn H; Leseman, Paul P M

BACKGROUND: Mathematics achievement is related to positive and negative emotions. Pekrun's control-value theory of achievement emotions suggests that students' self-concept (i.e., self-appraisal of ability) may be an important mediator of the relation between mathematics achievement and emotions.

Self-concept mediates the relation between achievement and emotions in mathematics

NARCIS (Netherlands)

Beek, J.P.J. van der; Ven, S.H.G. van der; Kroesbergen, E.H.; Leseman, P.P.M.

2017-01-01

Background: Mathematics achievement is related to positive and negative emotions. Pekrun's control-value theory of achievement emotions suggests that students' self-concept (i.e., self-appraisal of ability) may be an important mediator of the relation between mathematics achievement and emotions.

The Confrontation between General Relativity and Experiment

Directory of Open Access Journals (Sweden)

Clifford M. Will

2014-06-01

Full Text Available The status of experimental tests of general relativity and of theoretical frameworks for analyzing them is reviewed and updated. Einstein’s equivalence principle (EEP is well supported by experiments such as the Eötvös experiment, tests of local Lorentz invariance and clock experiments. Ongoing tests of EEP and of the inverse square law are searching for new interactions arising from unification or quantum gravity. Tests of general relativity at the post-Newtonian level have reached high precision, including the light deflection, the Shapiro time delay, the perihelion advance of Mercury, the Nordtvedt effect in lunar motion, and frame-dragging. Gravitational wave damping has been detected in an amount that agrees with general relativity to better than half a percent using the Hulse–Taylor binary pulsar, and a growing family of other binary pulsar systems is yielding new tests, especially of strong-field effects. Current and future tests of relativity will center on strong gravity and gravitational waves.

The Confrontation between General Relativity and Experiment.

Science.gov (United States)

Will, Clifford M

2014-01-01

The status of experimental tests of general relativity and of theoretical frameworks for analyzing them is reviewed and updated. Einstein's equivalence principle (EEP) is well supported by experiments such as the Eötvös experiment, tests of local Lorentz invariance and clock experiments. Ongoing tests of EEP and of the inverse square law are searching for new interactions arising from unification or quantum gravity. Tests of general relativity at the post-Newtonian level have reached high precision, including the light deflection, the Shapiro time delay, the perihelion advance of Mercury, the Nordtvedt effect in lunar motion, and frame-dragging. Gravitational wave damping has been detected in an amount that agrees with general relativity to better than half a percent using the Hulse-Taylor binary pulsar, and a growing family of other binary pulsar systems is yielding new tests, especially of strong-field effects. Current and future tests of relativity will center on strong gravity and gravitational waves.

Playing, Gaming, Working and Labouring: Framing the Con-cepts and Relations

Directory of Open Access Journals (Sweden)

Arwid Lund

2014-09-01

Full Text Available The aim of this article is to define the concepts of playing, working, gaming, and labouring, through a literature study, and to construct a typology. This typology will be used to create a field model that is structured by the horizontal parameters of qualitative-quantitative (characteristics and the vertical parameters of activity-result (in focus. It is shown how this model can be used to visualise different theoretical positions in empirical material, which connects to the concepts and their relations. Working and labouring are distinguished into a trans-historical and a historical, capitalist, category, and likewise playing and gaming, where the former is the trans-historical category and the latter the historical one. The main focus of the article, since working and labouring is well covered within the critical Marxist tradition, is on playing and its relation to working, with the aim of understanding and criticising the concept of playbour.

Constraints on stress-energy perturbations in general relativity

International Nuclear Information System (INIS)

Traschen, J.

1985-01-01

Conditions are found for the existence of integral constraints on stress-energy perturbations in general relativity. The integral constraints can be thought of as a general-relativistic generalization of the conservation of energy and momentum of matter perturbations in special relativity. The constraints are stated in terms of a vector field V, and the Robertson-Walker spacetimes are shown to have such constraint vectors. Although in general V is not a Killing vector, in a vacuum spacetime the constraint vectors are precisely the Killing vectors

A Rejoinder to Mackintosh and some Remarks on the Concept of General Intelligence

OpenAIRE

Heene, Moritz

2008-01-01

In 2000 Nicholas J. Mackintosh (2000) published an article in "Nature" referring to the concept of general intelligence ("g") claiming that there is clear empirical evidence for the existence of the g factor and psychologists are "united in their support of g". Surprisingly, his view remained yet unchallenged although this issue is by no means as clear-cut as Mackintosh argues. Let us therefore attempt to clarify some common but unfortunately major misconceptions about g, which Mackintosh, fo...

Longitudinal Factor Structure of General Self-Concept and Locus of Control among High School Students

Science.gov (United States)

Wang, Ze; Su, Ihui

2013-01-01

This study examined the longitudinal factor structure of general self-concept and locus of control among high school students over a 4-year period, with data from the National Educational Longitudinal Study of 1988. Measurement invariance was tested over time and across gender and ethnic groups; second-order piecewise latent growth models were…

Concept Analysis: Health-Promoting Behaviors Related to Human Papilloma Virus (HPV) Infection.

Science.gov (United States)

McCutcheon, Tonna; Schaar, Gina; Parker, Karen L

2015-01-01

The concept of health-promoting behaviors incorporates ideas presented in the Ottawa Charter of Public Health and the nursing-based Health Promotion Model. Despite the fact that the concept of health-promoting behaviors has a nursing influence, literature suggests nursing has inadequately developed and used this concept within nursing practice. A further review of literature regarding health promotion behaviors and the human papilloma virus suggest a distinct gap in nursing literature. This article presents a concept analysis of health-promoting behaviors related to the human papilloma virus in order to encourage the application of the concept into nursing practice, promote continued nursing research regarding this concept, and further expand the application of health-promoting behaviors to other situations and populations within the nursing discipline. Attributes of health-promoting behaviors are presented and include empowerment, participation, community, and a positive concept of health. Antecedents, consequences, and empirical referents are also presented, as are model, borderline, and contrary cases to help clarify the concept. Recommendations for human papilloma virus health-promoting behaviors within the nursing practice are also provided. © 2014 Wiley Periodicals, Inc.

One interpretation for both Quantum Mechanics and General Relativity

Energy Technology Data Exchange (ETDEWEB)

Halewijn, Ewoud

2014-07-01

In reconciling General Relativity with Quantum Mechanics, it is challenging to resolve the combined mathematical equations and to find an interpretation that makes sense ontologically. Such an interpretation has been developed by quantizing descriptive components in both the theories and other views. The resulting micro-components have been re-integrated within the scope of known gaps between science and 'the real world'. The odd peculiarities in these theories have been made look 'normal' by fully untraditionally answering fundamental questions. The interpretation is suggesting that we define time as a discrete operator and its eigenvalues as constraints on space-time manifolds, in order to reconcile the mathematical equations. Outside the mathematical arena we suggest reconsidering the concepts of Black Holes, the Big Bang, the epistemological problem of perception in philosophy and the supposed clash between scientific and the spiritual worldviews. It is concluded that developing one consistent ontological interpretation for both theorie is possible. It is a weird story, but it is making powerful suggestions for reviewing some of our fundamental convictions.

RELACIÓN ENTRE LOS CONSTRUCTOS AUTOCONTROL Y AUTOCONCEPTO EN NIÑOS Y JÓVENES/ RELATION BETWEEN SELF-CONTROL AND SELF-CONCEPT IN CHILD AND YOUNG

Directory of Open Access Journals (Sweden)

Fermino Fernandes Sisto*,

2010-10-01

Full Text Available RESUMENEste estudio ha investigado las relaciones entre el autocontrol y el autoconcepto en 1213 niños, de ambos sexos, de 2ºa 8º grado de una escuela pública, con edades variando de 8 a 14 años. Han sido aplicadas las Escalas Feminina eMasculina de Autocontrole y la Escala de Autoconceito Infanto-Juvenil. Han sido observadas correlaciones positivas ysignificativas entre los autoconceptos personal y social y todas las medidas. En relación al autoconcepto escolar ha habidoasociación negativa con el autocontrol en los varones, mientras que en las niñas la relación se ha dado apenas con elautocontrol de los sentimientos y emociones. Además, han sido evidenciadas correlaciones negativas y significativas entreel autoconcepto familiar y el autocontrol que se refiere a las normas y conductas sociales y de forma general en los varones.En las niñas, esa asociación se ha observado con el autocontrol que se refiere a las normas y conductas sociales, comotambién con el autocontrol general.ABSTRACTThe relationships between the self-control and self-concept were studied among 8-to-14-years-old 1213 children of bothsexes, attending the second to eighth grade of a public school. The tests administered were the Escalas Feminina eMasculina de Autocontrole and the Escala de Autoconceito Infanto-Juvenil. The results showed positive and significantcorrelation coefficients among the social and personal self-concept and all the measures of the self-control, although theacademic self-concept referred to the males showed negative and significant correlations in relation to the self-control, andto the females the self-concept correlated significantly with the measures of the self-control related to the feelings andemotions. Besides negative and significant correlations were highlighted among the familial self-concept and the selfcontrolreferred to norms and social behavior and, in general, with the males. Among the females, this association wasobserved with

Partial Differential Equations in General Relativity

International Nuclear Information System (INIS)

Choquet-Bruhat, Yvonne

2008-01-01

General relativity is a physical theory basic in the modeling of the universe at the large and small scales. Its mathematical formulation, the Einstein partial differential equations, are geometrically simple, but intricate for the analyst, involving both hyperbolic and elliptic PDE, with local and global problems. Many problems remain open though remarkable progress has been made recently towards their solutions. Alan Rendall's book states, in a down-to-earth form, fundamental results used to solve different types of equations. In each case he gives applications to special models as well as to general properties of Einsteinian spacetimes. A chapter on ODE contains, in particular, a detailed discussion of Bianchi spacetimes. A chapter entitled 'Elliptic systems' treats the Einstein constraints. A chapter entitled 'Hyperbolic systems' is followed by a chapter on the Cauchy problem and a chapter 'Global results' which contains recently proved theorems. A chapter is dedicated to the Einstein-Vlasov system, of which the author is a specialist. On the whole, the book surveys, in a concise though precise way, many essential results of recent interest in mathematical general relativity, and it is very clearly written. Each chapter is followed by an up to date bibliography. In conclusion, this book will be a valuable asset to relativists who wish to learn clearly-stated mathematical results and to mathematicians who want to penetrate into the subtleties of general relativity, as a mathematical and physical theory. (book review)

Partial Differential Equations in General Relativity

Energy Technology Data Exchange (ETDEWEB)

Choquet-Bruhat, Yvonne

2008-09-07

General relativity is a physical theory basic in the modeling of the universe at the large and small scales. Its mathematical formulation, the Einstein partial differential equations, are geometrically simple, but intricate for the analyst, involving both hyperbolic and elliptic PDE, with local and global problems. Many problems remain open though remarkable progress has been made recently towards their solutions. Alan Rendall's book states, in a down-to-earth form, fundamental results used to solve different types of equations. In each case he gives applications to special models as well as to general properties of Einsteinian spacetimes. A chapter on ODE contains, in particular, a detailed discussion of Bianchi spacetimes. A chapter entitled 'Elliptic systems' treats the Einstein constraints. A chapter entitled 'Hyperbolic systems' is followed by a chapter on the Cauchy problem and a chapter 'Global results' which contains recently proved theorems. A chapter is dedicated to the Einstein-Vlasov system, of which the author is a specialist. On the whole, the book surveys, in a concise though precise way, many essential results of recent interest in mathematical general relativity, and it is very clearly written. Each chapter is followed by an up to date bibliography. In conclusion, this book will be a valuable asset to relativists who wish to learn clearly-stated mathematical results and to mathematicians who want to penetrate into the subtleties of general relativity, as a mathematical and physical theory. (book review)

General relativity 50 years old

CERN Multimedia

1966-01-01

In May 1916, 'The Foundations of General Relativity Theory' by Albert Einstein was published in 'Annalen der Physik'. Fifty years later, this major contribution to scientific thought still has a rather isolated position with respect to the main-stream of scientific theory. (In contrast, the Special Theory of Relativity is one of the cornerstones of sub-nuclear physics.) To mark the anniversary of the publication of Einstein's paper a theoretician from CERN discusses the theory and its present status.

Advancing Uncertainty: Untangling and Discerning Related Concepts

OpenAIRE

Janice Penrod

2002-01-01

Methods of advancing concepts within the qualitative paradigm have been developed and articulated. In this section, I describe methodological perspectives of a project designed to advance the concept of uncertainty using multiple qualitative methods. Through a series of earlier studies, the concept of uncertainty arose repeatedly in varied contexts, working its way into prominence, and warranting further investigation. Processes of advanced concept analysis were used to initiate the formal in...

Hot Brakes and Energy-Related Concepts: Is Energy Lost?

Science.gov (United States)

Lopez, V.; Pinto, R.

2012-01-01

This paper describes a secondary school experience which is intended to help students to think profoundly about some energy-related concepts. It is quite different to other experiences of mechanics because the focus is not on the quantitative calculation of energy conservation but on the qualitative understanding of energy degradation. We first…

General Relativity and John Archibald Wheeler

CERN Document Server

Ciufolini, Ignazio

2010-01-01

Observational and experimental data pertaining to gravity and cosmology are changing our view of the Universe. General relativity is a fundamental key for the understanding of these observations and its theory is undergoing a continuing enhancement of its intersection with observational and experimental data. These data include direct observations and experiments carried out in our solar system, among which there are direct gravitational wave astronomy, frame dragging and tests of gravitational theories from solar system and spacecraft observations. This book explores John Archibald Wheeler's seminal and enduring contributions in relativistic astrophysics and includes: the General Theory of Relativity and Wheeler's influence; recent developments in the confrontation of relativity with experiments; the theory describing gravitational radiation, and its detection in Earth-based and space-based interferometer detectors as well as in Earth-based bar detectors; the mathematical description of the initial value pro...

General very special relativity in Finsler cosmology

International Nuclear Information System (INIS)

Kouretsis, A. P.; Stathakopoulos, M.; Stavrinos, P. C.

2009-01-01

General very special relativity (GVSR) is the curved space-time of very special relativity (VSR) proposed by Cohen and Glashow. The geometry of general very special relativity possesses a line element of Finsler geometry introduced by Bogoslovsky. We calculate the Einstein field equations and derive a modified Friedmann-Robertson-Walker cosmology for an osculating Riemannian space. The Friedmann equation of motion leads to an explanation of the cosmological acceleration in terms of an alternative non-Lorentz invariant theory. A first order approach for a primordial-spurionic vector field introduced into the metric gives back an estimation of the energy evolution and inflation.

Convergent Time-Varying Regression Models for Data Streams: Tracking Concept Drift by the Recursive Parzen-Based Generalized Regression Neural Networks.

Science.gov (United States)

Duda, Piotr; Jaworski, Maciej; Rutkowski, Leszek

2018-03-01

One of the greatest challenges in data mining is related to processing and analysis of massive data streams. Contrary to traditional static data mining problems, data streams require that each element is processed only once, the amount of allocated memory is constant and the models incorporate changes of investigated streams. A vast majority of available methods have been developed for data stream classification and only a few of them attempted to solve regression problems, using various heuristic approaches. In this paper, we develop mathematically justified regression models working in a time-varying environment. More specifically, we study incremental versions of generalized regression neural networks, called IGRNNs, and we prove their tracking properties - weak (in probability) and strong (with probability one) convergence assuming various concept drift scenarios. First, we present the IGRNNs, based on the Parzen kernels, for modeling stationary systems under nonstationary noise. Next, we extend our approach to modeling time-varying systems under nonstationary noise. We present several types of concept drifts to be handled by our approach in such a way that weak and strong convergence holds under certain conditions. Finally, in the series of simulations, we compare our method with commonly used heuristic approaches, based on forgetting mechanism or sliding windows, to deal with concept drift. Finally, we apply our concept in a real life scenario solving the problem of currency exchange rates prediction.

A Rejoinder to Mackintosh and some Remarks on the Concept of General Intelligence

OpenAIRE

Heene, Moritz

2017-01-01

In 2000 Nicholas J. Mackintosh (2000) published an article in Nature referring to the concept of general intelligence (“g”) claiming that there is clear empirical evidence for the existence of the g factor and psychologists are “...united in their support of g”. Surprisingly, his view remained yet unchallenged although this issue is by no means as clear-cut as Mackintosh argues. Let us therefore attempt to clarify some common but unfortunately major misconceptions about g, which Mackintosh, f...

Children's Self-Concepts as Related to Family Structure and Family Concept.

Science.gov (United States)

Parish, Joycelyn G.; Parish, Thomas S.

1983-01-01

Surveyed 426 children from intact, divorced, and reconstituted families, who responded to the Personal Attribute Inventory for Children to evaluate their families and themselves. Results showed a significant association between children's self-concepts and both their family structure and family concepts. (JAC)

Generalizing ecological site concepts of the Colorado Plateau for landscape-level applications

Science.gov (United States)

Duniway, Michael C.; Nauman, Travis; Johanson, Jamin K.; Green, Shane; Miller, Mark E.; Bestelmeyer, Brandon T.

2016-01-01

Numerous ecological site descriptions in the southern Utah portion of the Colorado Plateau can be difficult to navigate, so we held a workshop aimed at adding value and functionality to the current ecological site system.We created new groups of ecological sites and drafted state-and-transition models for these new groups.We were able to distill the current large number of ecological sites in the study area (ca. 150) into eight ecological site groups that capture important variability in ecosystem dynamics.Several inventory and monitoring programs and landscape scale planning actions will likely benefit from more generalized ecological site group concepts.

The Concept of Security in International Relations Theory

Directory of Open Access Journals (Sweden)

Gabriel Orozco

2006-01-01

Full Text Available The end of the Cold War and the emergence of globalisation have transformed the reality of International Relations, which has meant a change in the theories which this reality had assumed. The concept of security reveals itself as an organisational idea on the different phenomena of globalisation, carrying out a programme of research that goes beyond the realistic presumptions of military power or of the idealistic principles of research for peace. This article explores the new meanings of security for International Relations theory and discusses the theoretical models that influence policy design and that aim to confront the problems and challenges of security in globalisation.

'This stroke was sent…': Stroke-related illness concepts and ...

African Journals Online (AJOL)

Though there is evidence that stroke incidence is increasing even in low and middle income countries, there is no study of stroke-related illness concepts and HSB in Nigerians. Data from 960 educated Nigerians were analysed. Eight hundred and fifty four respondents (431 aged 20-40 years and 423 aged 41 years or ...

Teaching General Relativity to the Layperson

Science.gov (United States)

Egdall, Mark

2009-01-01

This paper describes a lay course on general relativity (GR) given at the Osher Lifelong Learning Institute at Florida International University. It is presented in six hour-and-a-half weekly sessions. Other courses offered by the author include special relativity (which precedes the course described here), quantum theory, and cosmology. Students…

General Relativity: Geometry Meets Physics

Science.gov (United States)

Thomsen, Dietrick E.

1975-01-01

Observing the relationship of general relativity and the geometry of space-time, the author questions whether the rest of physics has geometrical explanations. As a partial answer he discusses current research on subatomic particles employing geometric transformations, and cites the existence of geometrical definitions of physical quantities such…

Cosmological models in general relativity

Indian Academy of Sciences (India)

Cosmological models in general relativity. B B PAUL. Department of Physics, Nowgong College, Nagaon, Assam, India. MS received 4 October 2002; revised 6 March 2003; accepted 21 May 2003. Abstract. LRS Bianchi type-I space-time filled with perfect fluid is considered here with deceler- ation parameter as variable.

On generalization uniaxial stress-strain relation

International Nuclear Information System (INIS)

Sahay, C.; Dubey, R.N.

1980-01-01

Different forms of constitutive relations have been advanced for elastic, plastic and elastic-plastic behaviour of materials. It is shown that the various forms of the stress-strain relationship are specialized forms of generalization of a single stress-strain relation. For example, it is shown how the laws of elastic deformation, and the incremental and total deformation relationship for plastic behaviour are derivable from the Ramberg-Osgood relation. (orig.)

Self-Concept Mediates the Relation between Achievement and Emotions in Mathematics

Science.gov (United States)

Van der Beek, Jojanneke P. J.; Van der Ven, Sanne H. G.; Kroesbergen, Evelyn H.; Leseman, Paul P. M.

2017-01-01

Background: Mathematics achievement is related to positive and negative emotions. Pekrun's control-value theory of achievement emotions suggests that students' self-concept (i.e., self-appraisal of ability) may be an important mediator of the relation between mathematics achievement and emotions. Aims: The aims were (1) to investigate the…

Tests of General Relativity with GW150914

Science.gov (United States)

Abbott, B. P.; Abbott, R.; Abbott, T. D.; Abernathy, M. R.; Acernese, F.; Ackley, K.; Adams, C.; Adams, T.; Addesso, P.; Adhikari, R. X.; Adya, V. B.; Affeldt, C.; Agathos, M.; Agatsuma, K.; Aggarwal, N.; Aguiar, O. D.; Aiello, L.; Ain, A.; Ajith, P.; Allen, B.; Allocca, A.; Altin, P. A.; Anderson, S. B.; Anderson, W. G.; Arai, K.; Araya, M. C.; Arceneaux, C. C.; Areeda, J. S.; Arnaud, N.; Arun, K. G.; Ascenzi, S.; Ashton, G.; Ast, M.; Aston, S. M.; Astone, P.; Aufmuth, P.; Aulbert, C.; Babak, S.; Bacon, P.; Bader, M. K. M.; Baker, P. T.; Baldaccini, F.; Ballardin, G.; Ballmer, S. W.; Barayoga, J. C.; Barclay, S. E.; Barish, B. C.; Barker, D.; Barone, F.; Barr, B.; Barsotti, L.; Barsuglia, M.; Barta, D.; Bartlett, J.; Bartos, I.; Bassiri, R.; Basti, A.; Batch, J. C.; Baune, C.; Bavigadda, V.; Bazzan, M.; Behnke, B.; Bejger, M.; Bell, A. S.; Bell, C. J.; Berger, B. K.; Bergman, J.; Bergmann, G.; Berry, C. P. L.; Bersanetti, D.; Bertolini, A.; Betzwieser, J.; Bhagwat, S.; Bhandare, R.; Bilenko, I. A.; Billingsley, G.; Birch, J.; Birney, R.; Birnholtz, O.; Biscans, S.; Bisht, A.; Bitossi, M.; Biwer, C.; Bizouard, M. A.; Blackburn, J. K.; Blair, C. D.; Blair, D. G.; Blair, R. M.; Bloemen, S.; Bock, O.; Bodiya, T. P.; Boer, M.; Bogaert, G.; Bogan, C.; Bohe, A.; Bojtos, P.; Bond, C.; Bondu, F.; Bonnand, R.; Boom, B. A.; Bork, R.; Boschi, V.; Bose, S.; Bouffanais, Y.; Bozzi, A.; Bradaschia, C.; Brady, P. R.; Braginsky, V. B.; Branchesi, M.; Brau, J. E.; Briant, T.; Brillet, A.; Brinkmann, M.; Brisson, V.; Brockill, P.; Brooks, A. F.; Brown, D. A.; Brown, D. D.; Brown, N. M.; Buchanan, C. C.; Buikema, A.; Bulik, T.; Bulten, H. J.; Buonanno, A.; Buskulic, D.; Buy, C.; Byer, R. L.; Cadonati, L.; Cagnoli, G.; Cahillane, C.; Calderón Bustillo, J.; Callister, T.; Calloni, E.; Camp, J. B.; Cannon, K. C.; Cao, J.; Capano, C. D.; Capocasa, E.; Carbognani, F.; Caride, S.; Casanueva Diaz, J.; Casentini, C.; Caudill, S.; Cavaglià, M.; Cavalier, F.; Cavalieri, R.; Cella, G.; Cepeda, C. B.; Cerboni Baiardi, L.; Cerretani, G.; Cesarini, E.; Chakraborty, R.; Chalermsongsak, T.; Chamberlin, S. J.; Chan, M.; Chao, S.; Charlton, P.; Chassande-Mottin, E.; Chen, H. Y.; Chen, Y.; Cheng, C.; Chincarini, A.; Chiummo, A.; Cho, H. S.; Cho, M.; Chow, J. H.; Christensen, N.; Chu, Q.; Chua, S.; Chung, S.; Ciani, G.; Clara, F.; Clark, J. A.; Cleva, F.; Coccia, E.; Cohadon, P.-F.; Colla, A.; Collette, C. G.; Cominsky, L.; Constancio, M.; Conte, A.; Conti, L.; Cook, D.; Corbitt, T. R.; Cornish, N.; Corsi, A.; Cortese, S.; Costa, C. A.; Coughlin, M. W.; Coughlin, S. B.; Coulon, J.-P.; Countryman, S. T.; Couvares, P.; Cowan, E. E.; Coward, D. M.; Cowart, M. J.; Coyne, D. C.; Coyne, R.; Craig, K.; Creighton, J. D. E.; Cripe, J.; Crowder, S. G.; Cumming, A.; Cunningham, L.; Cuoco, E.; Dal Canton, T.; Danilishin, S. L.; D'Antonio, S.; Danzmann, K.; Darman, N. S.; Dattilo, V.; Dave, I.; Daveloza, H. P.; Davier, M.; Davies, G. S.; Daw, E. J.; Day, R.; DeBra, D.; Debreczeni, G.; Degallaix, J.; De Laurentis, M.; Deléglise, S.; Del Pozzo, W.; Denker, T.; Dent, T.; Dereli, H.; Dergachev, V.; De Rosa, R.; DeRosa, R. T.; DeSalvo, R.; Dhurandhar, S.; Díaz, M. C.; Di Fiore, L.; Di Giovanni, M.; Di Lieto, A.; Di Pace, S.; Di Palma, I.; Di Virgilio, A.; Dojcinoski, G.; Dolique, V.; Donovan, F.; Dooley, K. L.; Doravari, S.; Douglas, R.; Downes, T. P.; Drago, M.; Drever, R. W. P.; Driggers, J. C.; Du, Z.; Ducrot, M.; Dwyer, S. E.; Edo, T. B.; Edwards, M. C.; Effler, A.; Eggenstein, H.-B.; Ehrens, P.; Eichholz, J.; Eikenberry, S. S.; Engels, W.; Essick, R. C.; Etzel, T.; Evans, M.; Evans, T. M.; Everett, R.; Factourovich, M.; Fafone, V.; Fair, H.; Fairhurst, S.; Fan, X.; Fang, Q.; Farinon, S.; Farr, B.; Farr, W. M.; Favata, M.; Fays, M.; Fehrmann, H.; Fejer, M. M.; Ferrante, I.; Ferreira, E. C.; Ferrini, F.; Fidecaro, F.; Fiori, I.; Fiorucci, D.; Fisher, R. P.; Flaminio, R.; Fletcher, M.; Fournier, J.-D.; Franco, S.; Frasca, S.; Frasconi, F.; Frei, Z.; Freise, A.; Frey, R.; Frey, V.; Fricke, T. T.; Fritschel, P.; Frolov, V. V.; Fulda, P.; Fyffe, M.; Gabbard, H. A. G.; Gair, J. R.; Gammaitoni, L.; Gaonkar, S. G.; Garufi, F.; Gatto, A.; Gaur, G.; Gehrels, N.; Gemme, G.; Gendre, B.; Genin, E.; Gennai, A.; George, J.; Gergely, L.; Germain, V.; Ghosh, Abhirup; Ghosh, Archisman; Ghosh, S.; Giaime, J. A.; Giardina, K. D.; Giazotto, A.; Gill, K.; Glaefke, A.; Goetz, E.; Goetz, R.; Gondan, L.; González, G.; Gonzalez Castro, J. M.; Gopakumar, A.; Gordon, N. A.; Gorodetsky, M. L.; Gossan, S. E.; Gosselin, M.; Gouaty, R.; Graef, C.; Graff, P. B.; Granata, M.; Grant, A.; Gras, S.; Gray, C.; Greco, G.; Green, A. C.; Groot, P.; Grote, H.; Grunewald, S.; Guidi, G. M.; Guo, X.; Gupta, A.; Gupta, M. K.; Gushwa, K. E.; Gustafson, E. K.; Gustafson, R.; Hacker, J. J.; Hall, B. R.; Hall, E. D.; Hammond, G.; Haney, M.; Hanke, M. M.; Hanks, J.; Hanna, C.; Hannam, M. D.; Hanson, J.; Hardwick, T.; Harms, J.; Harry, G. M.; Harry, I. W.; Hart, M. J.; Hartman, M. T.; Haster, C.-J.; Haughian, K.; Healy, J.; Heidmann, A.; Heintze, M. C.; Heitmann, H.; Hello, P.; Hemming, G.; Hendry, M.; Heng, I. S.; Hennig, J.; Heptonstall, A. W.; Heurs, M.; Hild, S.; Hoak, D.; Hodge, K. A.; Hofman, D.; Hollitt, S. E.; Holt, K.; Holz, D. E.; Hopkins, P.; Hosken, D. J.; Hough, J.; Houston, E. A.; Howell, E. J.; Hu, Y. M.; Huang, S.; Huerta, E. A.; Huet, D.; Hughey, B.; Husa, S.; Huttner, S. H.; Huynh-Dinh, T.; Idrisy, A.; Indik, N.; Ingram, D. R.; Inta, R.; Isa, H. N.; Isac, J.-M.; Isi, M.; Islas, G.; Isogai, T.; Iyer, B. R.; Izumi, K.; Jacqmin, T.; Jang, H.; Jani, K.; Jaranowski, P.; Jawahar, S.; Jiménez-Forteza, F.; Johnson, W. W.; Johnson-McDaniel, N. K.; Jones, D. I.; Jones, R.; Jonker, R. J. G.; Ju, L.; Haris, M. K.; Kalaghatgi, C. V.; Kalogera, V.; Kandhasamy, S.; Kang, G.; Kanner, J. B.; Karki, S.; Kasprzack, M.; Katsavounidis, E.; Katzman, W.; Kaufer, S.; Kaur, T.; Kawabe, K.; Kawazoe, F.; Kéfélian, F.; Kehl, M. S.; Keitel, D.; Kelley, D. B.; Kells, W.; Kennedy, R.; Key, J. S.; Khalaidovski, A.; Khalili, F. Y.; Khan, I.; Khan, S.; Khan, Z.; Khazanov, E. A.; Kijbunchoo, N.; Kim, C.; Kim, J.; Kim, K.; Kim, Nam-Gyu; Kim, Namjun; Kim, Y.-M.; King, E. J.; King, P. J.; Kinzel, D. L.; Kissel, J. S.; Kleybolte, L.; Klimenko, S.; Koehlenbeck, S. M.; Kokeyama, K.; Koley, S.; Kondrashov, V.; Kontos, A.; Korobko, M.; Korth, W. Z.; Kowalska, I.; Kozak, D. B.; Kringel, V.; Krishnan, B.; Królak, A.; Krueger, C.; Kuehn, G.; Kumar, P.; Kuo, L.; Kutynia, A.; Lackey, B. D.; Landry, M.; Lange, J.; Lantz, B.; Lasky, P. D.; Lazzarini, A.; Lazzaro, C.; Leaci, P.; Leavey, S.; Lebigot, E. O.; Lee, C. H.; Lee, H. K.; Lee, H. M.; Lee, K.; Lenon, A.; Leonardi, M.; Leong, J. R.; Leroy, N.; Letendre, N.; Levin, Y.; Levine, B. M.; Li, T. G. F.; Libson, A.; Littenberg, T. B.; Lockerbie, N. A.; Logue, J.; Lombardi, A. L.; London, L. T.; Lord, J. E.; Lorenzini, M.; Loriette, V.; Lormand, M.; Losurdo, G.; Lough, J. D.; Lousto, C. O.; Lovelace, G.; Lück, H.; Lundgren, A. P.; Luo, J.; Lynch, R.; Ma, Y.; MacDonald, T.; Machenschalk, B.; MacInnis, M.; Macleod, D. M.; Magaña-Sandoval, F.; Magee, R. M.; Mageswaran, M.; Majorana, E.; Maksimovic, I.; Malvezzi, V.; Man, N.; Mandel, I.; Mandic, V.; Mangano, V.; Mansell, G. L.; Manske, M.; Mantovani, M.; Marchesoni, F.; Marion, F.; Márka, S.; Márka, Z.; Markosyan, A. S.; Maros, E.; Martelli, F.; Martellini, L.; Martin, I. W.; Martin, R. M.; Martynov, D. V.; Marx, J. N.; Mason, K.; Masserot, A.; Massinger, T. J.; Masso-Reid, M.; Matichard, F.; Matone, L.; Mavalvala, N.; Mazumder, N.; Mazzolo, G.; McCarthy, R.; McClelland, D. E.; McCormick, S.; McGuire, S. C.; McIntyre, G.; McIver, J.; McManus, D. J.; McWilliams, S. T.; Meacher, D.; Meadors, G. D.; Meidam, J.; Melatos, A.; Mendell, G.; Mendoza-Gandara, D.; Mercer, R. A.; Merilh, E.; Merzougui, M.; Meshkov, S.; Messenger, C.; Messick, C.; Meyers, P. M.; Mezzani, F.; Miao, H.; Michel, C.; Middleton, H.; Mikhailov, E. E.; Milano, L.; Miller, J.; Millhouse, M.; Minenkov, Y.; Ming, J.; Mirshekari, S.; Mishra, C.; Mitra, S.; Mitrofanov, V. P.; Mitselmakher, G.; Mittleman, R.; Moggi, A.; Mohan, M.; Mohapatra, S. R. P.; Montani, M.; Moore, B. C.; Moore, C. J.; Moraru, D.; Moreno, G.; Morriss, S. R.; Mossavi, K.; Mours, B.; Mow-Lowry, C. M.; Mueller, C. L.; Mueller, G.; Muir, A. W.; Mukherjee, Arunava; Mukherjee, D.; Mukherjee, S.; Mukund, N.; Mullavey, A.; Munch, J.; Murphy, D. J.; Murray, P. G.; Mytidis, A.; Nardecchia, I.; Naticchioni, L.; Nayak, R. K.; Necula, V.; Nedkova, K.; Nelemans, G.; Neri, M.; Neunzert, A.; Newton, G.; Nguyen, T. T.; Nielsen, A. B.; Nissanke, S.; Nitz, A.; Nocera, F.; Nolting, D.; Normandin, M. E.; Nuttall, L. K.; Oberling, J.; Ochsner, E.; O'Dell, J.; Oelker, E.; Ogin, G. H.; Oh, J. J.; Oh, S. H.; Ohme, F.; Oliver, M.; Oppermann, P.; Oram, Richard J.; O'Reilly, B.; O'Shaughnessy, R.; Ottaway, D. J.; Ottens, R. S.; Overmier, H.; Owen, B. J.; Pai, A.; Pai, S. A.; Palamos, J. R.; Palashov, O.; Palomba, C.; Pal-Singh, A.; Pan, H.; Pan, Y.; Pankow, C.; Pannarale, F.; Pant, B. C.; Paoletti, F.; Paoli, A.; Papa, M. A.; Paris, H. R.; Parker, W.; Pascucci, D.; Pasqualetti, A.; Passaquieti, R.; Passuello, D.; Patricelli, B.; Patrick, Z.; Pearlstone, B. L.; Pedraza, M.; Pedurand, R.; Pekowsky, L.; Pele, A.; Penn, S.; Perreca, A.; Pfeiffer, H. P.; Phelps, M.; Piccinni, O.; Pichot, M.; Piergiovanni, F.; Pierro, V.; Pillant, G.; Pinard, L.; Pinto, I. M.; Pitkin, M.; Poggiani, R.; Popolizio, P.; Post, A.; Powell, J.; Prasad, J.; Predoi, V.; Premachandra, S. S.; Prestegard, T.; Price, L. R.; Prijatelj, M.; Principe, M.; Privitera, S.; Prix, R.; Prodi, G. A.; Prokhorov, L.; Puncken, O.; Punturo, M.; Puppo, P.; Pürrer, M.; Qi, H.; Qin, J.; Quetschke, V.; Quintero, E. A.; Quitzow-James, R.; Raab, F. J.; Rabeling, D. S.; Radkins, H.; Raffai, P.; Raja, S.; Rakhmanov, M.; Rapagnani, P.; Raymond, V.; Razzano, M.; Re, V.; Read, J.; Reed, C. M.; Regimbau, T.; Rei, L.; Reid, S.; Reitze, D. H.; Rew, H.; Reyes, S. D.; Ricci, F.; Riles, K.; Robertson, N. A.; Robie, R.; Robinet, F.; Rocchi, A.; Rolland, L.; Rollins, J. G.; Roma, V. J.; Romano, R.; Romanov, G.; Romie, J. H.; Rosińska, D.; Rowan, S.; Rüdiger, A.; Ruggi, P.; Ryan, K.; Sachdev, S.; Sadecki, T.; Sadeghian, L.; Salconi, L.; Saleem, M.; Salemi, F.; Samajdar, A.; Sammut, L.; Sanchez, E. J.; Sandberg, V.; Sandeen, B.; Sanders, J. R.; Sassolas, B.; Sathyaprakash, B. S.; Saulson, P. R.; Sauter, O.; Savage, R. L.; Sawadsky, A.; Schale, P.; Schilling, R.; Schmidt, J.; Schmidt, P.; Schnabel, R.; Schofield, R. M. S.; Schönbeck, A.; Schreiber, E.; Schuette, D.; Schutz, B. F.; Scott, J.; Scott, S. M.; Sellers, D.; Sengupta, A. S.; Sentenac, D.; Sequino, V.; Sergeev, A.; Serna, G.; Setyawati, Y.; Sevigny, A.; Shaddock, D. A.; Shah, S.; Shahriar, M. S.; Shaltev, M.; Shao, Z.; Shapiro, B.; Shawhan, P.; Sheperd, A.; Shoemaker, D. H.; Shoemaker, D. M.; Siellez, K.; Siemens, X.; Sigg, D.; Silva, A. D.; Simakov, D.; Singer, A.; Singer, L. P.; Singh, A.; Singh, R.; Singhal, A.; Sintes, A. M.; Slagmolen, B. J. J.; Smith, J. R.; Smith, N. D.; Smith, R. J. E.; Son, E. J.; Sorazu, B.; Sorrentino, F.; Souradeep, T.; Srivastava, A. K.; Staley, A.; Steinke, M.; Steinlechner, J.; Steinlechner, S.; Steinmeyer, D.; Stephens, B. C.; Stone, R.; Strain, K. A.; Straniero, N.; Stratta, G.; Strauss, N. A.; Strigin, S.; Sturani, R.; Stuver, A. L.; Summerscales, T. Z.; Sun, L.; Sutton, P. J.; Swinkels, B. L.; Szczepańczyk, M. J.; Tacca, M.; Talukder, D.; Tanner, D. B.; Tápai, M.; Tarabrin, S. P.; Taracchini, A.; Taylor, R.; Theeg, T.; Thirugnanasambandam, M. P.; Thomas, E. G.; Thomas, M.; Thomas, P.; Thorne, K. A.; Thorne, K. S.; Thrane, E.; Tiwari, S.; Tiwari, V.; Tokmakov, K. V.; Tomlinson, C.; Tonelli, M.; Torres, C. V.; Torrie, C. I.; Töyrä, D.; Travasso, F.; Traylor, G.; Trifirò, D.; Tringali, M. C.; Trozzo, L.; Tse, M.; Turconi, M.; Tuyenbayev, D.; Ugolini, D.; Unnikrishnan, C. S.; Urban, A. L.; Usman, S. A.; Vahlbruch, H.; Vajente, G.; Valdes, G.; Vallisneri, M.; van Bakel, N.; van Beuzekom, M.; van den Brand, J. F. J.; Van Den Broeck, C.; Vander-Hyde, D. C.; van der Schaaf, L.; van Heijningen, J. V.; van Veggel, A. A.; Vardaro, M.; Vass, S.; Vasúth, M.; Vaulin, R.; Vecchio, A.; Vedovato, G.; Veitch, J.; Veitch, P. J.; Venkateswara, K.; Verkindt, D.; Vetrano, F.; Viceré, A.; Vinciguerra, S.; Vine, D. J.; Vinet, J.-Y.; Vitale, S.; Vo, T.; Vocca, H.; Vorvick, C.; Voss, D.; Vousden, W. D.; Vyatchanin, S. P.; Wade, A. R.; Wade, L. E.; Wade, M.; Walker, M.; Wallace, L.; Walsh, S.; Wang, G.; Wang, H.; Wang, M.; Wang, X.; Wang, Y.; Ward, R. L.; Warner, J.; Was, M.; Weaver, B.; Wei, L.-W.; Weinert, M.; Weinstein, A. J.; Weiss, R.; Welborn, T.; Wen, L.; Weßels, P.; Westphal, T.; Wette, K.; Whelan, J. T.; White, D. J.; Whiting, B. F.; Williams, D.; Williams, R. D.; Williamson, A. R.; Willis, J. L.; Willke, B.; Wimmer, M. H.; Winkler, W.; Wipf, C. C.; Wittel, H.; Woan, G.; Worden, J.; Wright, J. L.; Wu, G.; Yablon, J.; Yam, W.; Yamamoto, H.; Yancey, C. C.; Yap, M. J.; Yu, H.; Yvert, M.; ZadroŻny, A.; Zangrando, L.; Zanolin, M.; Zendri, J.-P.; Zevin, M.; Zhang, F.; Zhang, L.; Zhang, M.; Zhang, Y.; Zhao, C.; Zhou, M.; Zhou, Z.; Zhu, X. J.; Zucker, M. E.; Zuraw, S. E.; Zweizig, J.; Boyle, M.; Campanelli, M.; Hemberger, D. A.; Kidder, L. E.; Ossokine, S.; Scheel, M. A.; Szilagyi, B.; Teukolsky, S.; Zlochower, Y.; LIGO Scientific; Virgo Collaborations

2016-06-01

The LIGO detection of GW150914 provides an unprecedented opportunity to study the two-body motion of a compact-object binary in the large-velocity, highly nonlinear regime, and to witness the final merger of the binary and the excitation of uniquely relativistic modes of the gravitational field. We carry out several investigations to determine whether GW150914 is consistent with a binary black-hole merger in general relativity. We find that the final remnant's mass and spin, as determined from the low-frequency (inspiral) and high-frequency (postinspiral) phases of the signal, are mutually consistent with the binary black-hole solution in general relativity. Furthermore, the data following the peak of GW150914 are consistent with the least-damped quasinormal mode inferred from the mass and spin of the remnant black hole. By using waveform models that allow for parametrized general-relativity violations during the inspiral and merger phases, we perform quantitative tests on the gravitational-wave phase in the dynamical regime and we determine the first empirical bounds on several high-order post-Newtonian coefficients. We constrain the graviton Compton wavelength, assuming that gravitons are dispersed in vacuum in the same way as particles with mass, obtaining a 90%-confidence lower bound of 1013 km . In conclusion, within our statistical uncertainties, we find no evidence for violations of general relativity in the genuinely strong-field regime of gravity.

Prelinguistic Relational Concepts: Investigating Analogical Processing in Infants

Science.gov (United States)

Ferry, Alissa L.; Hespos, Susan J.; Gentner, Dedre

2015-01-01

This research asks whether analogical processing ability is present in human infants, using the simplest and most basic relation--the "same-different" relation. Experiment 1 (N = 26) tested whether 7- and 9-month-olds spontaneously detect and generalize these relations from a single example, as previous research has suggested. The…

Axisymmetric solution with charge in general relativity

International Nuclear Information System (INIS)

Arutyunyan, G.G.; Papoyan, V.V.

1989-01-01

The possibility of generating solutions to the equations of general relativity from known solutions of the generalized theory of gravitation and vice versa is proved. An electrovac solution to Einstein's equations that describes a static axisymmetric gravitational field is found. 14 refs

Results from Numerical General Relativity

Science.gov (United States)

Baker, John G.

2011-01-01

For several years numerical simulations have been revealing the details of general relativity's predictions for the dynamical interactions of merging black holes. I will review what has been learned of the rich phenomenology of these mergers and the resulting gravitational wave signatures. These wave forms provide a potentially observable record of the powerful astronomical events, a central target of gravitational wave astronomy. Asymmetric radiation can produce a thrust on the system which may accelerate the single black hole resulting from the merger to high relative velocity.

Relativity the special and the general theory

CERN Document Server

Einstein, Albert

2015-01-01

After completing the final version of his general theory of relativity in November 1915, Albert Einstein wrote a book about relativity for a popular audience. His intention was "to give an exact insight into the theory of relativity to those readers who, from a general scientific and philosophical point of view, are interested in the theory, but who are not conversant with the mathematical apparatus of theoretical physics." The book remains one of the most lucid explanations of the special and general theories ever written. In the early 1920s alone, it was translated into ten languages, and fifteen editions in the original German appeared over the course of Einstein's lifetime. This new edition of Einstein's celebrated book features an authoritative English translation of the text along with an introduction and a reading companion by Hanoch Gutfreund and Jürgen Renn that examines the evolution of Einstein's thinking and casts his ideas in a broader present-day context. A special chapter explores the history...

Homothetic motions in general relativity

International Nuclear Information System (INIS)

McIntosh, C.B.G.

1976-01-01

Properties of homothetic or self-similar motions in general relativity are examined with particular reference to vacuum and perfect-fluid space-times. The role of the homothetic bivector with components Hsub((a;b)) formed from the homothetic vector H is discussed in some detail. It is proved that a vacuum space-time only admits a nontrivial homothetic motion if the homothetic vector field is non-null and is not hypersurface orthogonal. As a subcase of a more general result it is shown that a perfect-fluid space-time cannot admit a non-trivial homothetic vector which is orthogonal to the fluid velocity 4-vector. (author)

Sustainable refurbishment of exterior walls and building facades. Final report, Part B - General refurbishment concepts

Energy Technology Data Exchange (ETDEWEB)

Vares, S.; Pulakka, S.; Toratti, T. [and others

2012-11-01

This report is the second part of the final report of Sustainable refurbishment of building facades and exterior walls (SUSREF). SUSREF project was a collaborative (small/medium size) research project within the 7th Framework Programme of the Commission and it was financed under the theme Environment (including climate change) (Grant agreement no. 226858). The project started in October 1st 2009 and ended in April 30th 2012. The project included 11 partners from five countries. SUSREF developed sustainable concepts and technologies for the refurbishment of building facades and external walls. This report together with SUSREF Final report Part B and SUSREF Final Report Part C introduce the main results of the project. Part A focuses on methodological issues. The descriptions of the concepts and the assessment results of the developed concepts are presented in SUSREF Final report part B (generic concepts) and SUSREF Final report Part C (SME concepts). The following list shows the sustainability assessment criteria defined by the SUSREF project. These are Durability; Impact on energy demand for heating; Impact on energy demand for cooling; Impact on renewable energy use potential; Impact on daylight; Environmental impact of manufacture and maintenance; Indoor air quality and acoustics; Structural stability; Fire safety; Aesthetic quality; Effect on cultural heritage; Life cycle costs; Need for care and maintenance; Disturbance to the tenants and to the site; Buildability. This report presents sustainability assessment results of general refurbishment concepts and gives recommendations on the basis of the results. The report covers the following refurbishment cases - External insulation - Internal insulation - Cavity wall insulation - Replacement Insulation during renovation.

General Relativity: horizons for tests

Science.gov (United States)

Yatskiv, Ya. S.; Alexandrov, A. N.; Vavilova, I. B.; Zhdanov, V. I.; Zhuk, A. I.; Kudrya, Yu. N.; Parnovsky, S. L.; Fedorova, E. V.; Khmil, S. V.

2013-12-01

Theoretical basis of the General Relativity Theory (GRT), its experimental tests as well as GRT applications are briefly summarized taking into account the results of the last decade. The monograph addresses scientists, post-graduated students, and students specialized in the natural sciences as well as everyone who takes an interest in GRT.

BOOK REVIEW: Partial Differential Equations in General Relativity

Science.gov (United States)

Halburd, Rodney G.

2008-11-01

Although many books on general relativity contain an overview of the relevant background material from differential geometry, very little attention is usually paid to background material from the theory of differential equations. This is understandable in a first course on relativity but it often limits the kinds of problems that can be studied rigorously. Einstein's field equations lie at the heart of general relativity. They are a system of partial differential equations (PDEs) relating the curvature of spacetime to properties of matter. A central part of most problems in general relativity is to extract information about solutions of these equations. Most standard texts achieve this by studying exact solutions or numerical and analytical approximations. In the book under review, Alan Rendall emphasises the role of rigorous qualitative methods in general relativity. There has long been a need for such a book, giving a broad overview of the relevant background from the theory of partial differential equations, and not just from differential geometry. It should be noted that the book also covers the basic theory of ordinary differential equations. Although there are many good books on the rigorous theory of PDEs, methods related to the Einstein equations deserve special attention, not only because of the complexity and importance of these equations, but because these equations do not fit into any of the standard classes of equations (elliptic, parabolic, hyperbolic) that one typically encounters in a course on PDEs. Even specifying exactly what ones means by a Cauchy problem in general relativity requires considerable care. The main problem here is that the manifold on which the solution is defined is determined by the solution itself. This means that one does not simply define data on a submanifold. Rendall's book gives a good overview of applications and results from the qualitative theory of PDEs to general relativity. It would be impossible to give detailed

Analysis of Lamellar Structures with Application of Generalized Functions

Directory of Open Access Journals (Sweden)

Kipiani Gela

2016-12-01

Full Text Available Theory of differential equations in respect of the functional area is based on the basic concepts on generalized functions and splines. There are some basic concepts related to the theory of generalized functions and their properties are considered in relation to the rod systems and lamellar structures. The application of generalized functions gives the possibility to effectively calculate step-variable stiffness lamellar structures. There are also widely applied structures, in that several in which a number of parallel load bearing layers are interconnected by discrete-elastic links. For analysis of system under study, such as design diagrams, there are applied discrete and discrete-continual models.

Tests of General Relativity with GW150914.

Science.gov (United States)

Abbott, B P; Abbott, R; Abbott, T D; Abernathy, M R; Acernese, F; Ackley, K; Adams, C; Adams, T; Addesso, P; Adhikari, R X; Adya, V B; Affeldt, C; Agathos, M; Agatsuma, K; Aggarwal, N; Aguiar, O D; Aiello, L; Ain, A; Ajith, P; Allen, B; Allocca, A; Altin, P A; Anderson, S B; Anderson, W G; Arai, K; Araya, M C; Arceneaux, C C; Areeda, J S; Arnaud, N; Arun, K G; Ascenzi, S; Ashton, G; Ast, M; Aston, S M; Astone, P; Aufmuth, P; Aulbert, C; Babak, S; Bacon, P; Bader, M K M; Baker, P T; Baldaccini, F; Ballardin, G; Ballmer, S W; Barayoga, J C; Barclay, S E; Barish, B C; Barker, D; Barone, F; Barr, B; Barsotti, L; Barsuglia, M; Barta, D; Bartlett, J; Bartos, I; Bassiri, R; Basti, A; Batch, J C; Baune, C; Bavigadda, V; Bazzan, M; Behnke, B; Bejger, M; Bell, A S; Bell, C J; Berger, B K; Bergman, J; Bergmann, G; Berry, C P L; Bersanetti, D; Bertolini, A; Betzwieser, J; Bhagwat, S; Bhandare, R; Bilenko, I A; Billingsley, G; Birch, J; Birney, R; Birnholtz, O; Biscans, S; Bisht, A; Bitossi, M; Biwer, C; 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Downes, T P; Drago, M; Drever, R W P; Driggers, J C; Du, Z; Ducrot, M; Dwyer, S E; Edo, T B; Edwards, M C; Effler, A; Eggenstein, H-B; Ehrens, P; Eichholz, J; Eikenberry, S S; Engels, W; Essick, R C; Etzel, T; Evans, M; Evans, T M; Everett, R; Factourovich, M; Fafone, V; Fair, H; Fairhurst, S; Fan, X; Fang, Q; Farinon, S; Farr, B; Farr, W M; Favata, M; Fays, M; Fehrmann, H; Fejer, M M; Ferrante, I; Ferreira, E C; Ferrini, F; Fidecaro, F; Fiori, I; Fiorucci, D; Fisher, R P; Flaminio, R; Fletcher, M; Fournier, J-D; Franco, S; Frasca, S; Frasconi, F; Frei, Z; Freise, A; Frey, R; Frey, V; Fricke, T T; Fritschel, P; Frolov, V V; Fulda, P; Fyffe, M; Gabbard, H A G; Gair, J R; Gammaitoni, L; Gaonkar, S G; Garufi, F; Gatto, A; Gaur, G; Gehrels, N; Gemme, G; Gendre, B; Genin, E; Gennai, A; George, J; Gergely, L; Germain, V; Ghosh, Abhirup; Ghosh, Archisman; Ghosh, S; Giaime, J A; Giardina, K D; Giazotto, A; Gill, K; Glaefke, A; Goetz, E; Goetz, R; Gondan, L; González, G; Gonzalez Castro, J M; Gopakumar, A; Gordon, N A; Gorodetsky, M L; Gossan, S E; Gosselin, M; Gouaty, R; Graef, C; Graff, P B; Granata, M; Grant, A; Gras, S; Gray, C; Greco, G; Green, A C; Groot, P; Grote, H; Grunewald, S; Guidi, G M; Guo, X; Gupta, A; Gupta, M K; Gushwa, K E; Gustafson, E K; Gustafson, R; Hacker, J J; Hall, B R; Hall, E D; Hammond, G; Haney, M; Hanke, M M; Hanks, J; Hanna, C; Hannam, M D; Hanson, J; Hardwick, T; Harms, J; Harry, G M; Harry, I W; Hart, M J; Hartman, M T; Haster, C-J; Haughian, K; Healy, J; Heidmann, A; Heintze, M C; Heitmann, H; Hello, P; Hemming, G; Hendry, M; Heng, I S; Hennig, J; Heptonstall, A W; Heurs, M; Hild, S; Hoak, D; Hodge, K A; Hofman, D; Hollitt, S E; Holt, K; Holz, D E; Hopkins, P; Hosken, D J; Hough, J; Houston, E A; Howell, E J; Hu, Y M; Huang, S; Huerta, E A; Huet, D; Hughey, B; Husa, S; Huttner, S H; Huynh-Dinh, T; Idrisy, A; Indik, N; Ingram, D R; Inta, R; Isa, H N; Isac, J-M; Isi, M; Islas, G; Isogai, T; Iyer, B R; Izumi, K; Jacqmin, T; Jang, H; Jani, K; Jaranowski, P; Jawahar, S; Jiménez-Forteza, F; Johnson, W W; Johnson-McDaniel, N K; Jones, D I; Jones, R; Jonker, R J G; Ju, L; Haris, M K; Kalaghatgi, C V; Kalogera, V; Kandhasamy, S; Kang, G; Kanner, J B; Karki, S; Kasprzack, M; Katsavounidis, E; Katzman, W; Kaufer, S; Kaur, T; Kawabe, K; Kawazoe, F; Kéfélian, F; Kehl, M S; Keitel, D; Kelley, D B; Kells, W; Kennedy, R; Key, J S; Khalaidovski, A; Khalili, F Y; Khan, I; Khan, S; Khan, Z; Khazanov, E A; Kijbunchoo, N; Kim, C; Kim, J; Kim, K; Kim, Nam-Gyu; Kim, Namjun; Kim, Y-M; King, E J; King, P J; Kinzel, D L; Kissel, J S; Kleybolte, L; Klimenko, S; Koehlenbeck, S M; Kokeyama, K; Koley, S; Kondrashov, V; Kontos, A; Korobko, M; Korth, W Z; Kowalska, I; Kozak, D B; Kringel, V; Krishnan, B; Królak, A; Krueger, C; Kuehn, G; Kumar, P; Kuo, L; Kutynia, A; Lackey, B D; Landry, M; Lange, J; Lantz, B; Lasky, P D; Lazzarini, A; Lazzaro, C; Leaci, P; Leavey, S; Lebigot, E O; Lee, C H; Lee, H K; Lee, H M; Lee, K; Lenon, A; Leonardi, M; Leong, J R; Leroy, N; Letendre, N; Levin, Y; Levine, B M; Li, T G F; Libson, A; Littenberg, T B; Lockerbie, N A; Logue, J; Lombardi, A L; London, L T; Lord, J E; Lorenzini, M; Loriette, V; Lormand, M; Losurdo, G; Lough, J D; Lousto, C O; Lovelace, G; Lück, H; Lundgren, A P; Luo, J; Lynch, R; Ma, Y; MacDonald, T; Machenschalk, B; MacInnis, M; Macleod, D M; Magaña-Sandoval, F; Magee, R M; Mageswaran, M; Majorana, E; Maksimovic, I; Malvezzi, V; Man, N; Mandel, I; Mandic, V; Mangano, V; Mansell, G L; Manske, M; Mantovani, M; Marchesoni, F; Marion, F; Márka, S; Márka, Z; Markosyan, A S; Maros, E; Martelli, F; Martellini, L; Martin, I W; Martin, R M; Martynov, D V; Marx, J N; Mason, K; Masserot, A; Massinger, T J; Masso-Reid, M; Matichard, F; Matone, L; Mavalvala, N; Mazumder, N; Mazzolo, G; McCarthy, R; McClelland, D E; McCormick, S; McGuire, S C; McIntyre, G; McIver, J; McManus, D J; McWilliams, S T; Meacher, D; Meadors, G D; Meidam, J; Melatos, A; Mendell, G; Mendoza-Gandara, D; Mercer, R A; Merilh, E; Merzougui, M; Meshkov, S; Messenger, C; Messick, C; Meyers, P M; Mezzani, F; Miao, H; Michel, C; Middleton, H; Mikhailov, E E; Milano, L; Miller, J; Millhouse, M; Minenkov, Y; Ming, J; Mirshekari, S; Mishra, C; Mitra, S; Mitrofanov, V P; Mitselmakher, G; Mittleman, R; Moggi, A; Mohan, M; Mohapatra, S R P; Montani, M; Moore, B C; Moore, C J; Moraru, D; Moreno, G; Morriss, S R; Mossavi, K; Mours, B; Mow-Lowry, C M; Mueller, C L; Mueller, G; Muir, A W; Mukherjee, Arunava; Mukherjee, D; Mukherjee, S; Mukund, N; Mullavey, A; Munch, J; Murphy, D J; Murray, P G; Mytidis, A; Nardecchia, I; Naticchioni, L; Nayak, R K; Necula, V; Nedkova, K; Nelemans, G; Neri, M; Neunzert, A; Newton, G; Nguyen, T T; Nielsen, A B; Nissanke, S; Nitz, A; Nocera, F; Nolting, D; Normandin, M E; Nuttall, L K; Oberling, J; Ochsner, E; O'Dell, J; Oelker, E; Ogin, G H; Oh, J J; Oh, S H; Ohme, F; Oliver, M; Oppermann, P; Oram, Richard J; O'Reilly, B; O'Shaughnessy, R; Ottaway, D J; Ottens, R S; Overmier, H; Owen, B J; Pai, A; Pai, S A; Palamos, J R; Palashov, O; Palomba, C; Pal-Singh, A; Pan, H; Pan, Y; Pankow, C; Pannarale, F; Pant, B C; Paoletti, F; Paoli, A; Papa, M A; Paris, H R; Parker, W; Pascucci, D; Pasqualetti, A; Passaquieti, R; Passuello, D; Patricelli, B; Patrick, Z; Pearlstone, B L; Pedraza, M; Pedurand, R; Pekowsky, L; Pele, A; Penn, S; Perreca, A; Pfeiffer, H P; Phelps, M; Piccinni, O; Pichot, M; Piergiovanni, F; Pierro, V; Pillant, G; Pinard, L; Pinto, I M; Pitkin, M; Poggiani, R; Popolizio, P; Post, A; Powell, J; Prasad, J; Predoi, V; Premachandra, S S; Prestegard, T; Price, L R; Prijatelj, M; Principe, M; Privitera, S; Prix, R; Prodi, G A; Prokhorov, L; Puncken, O; Punturo, M; Puppo, P; Pürrer, M; Qi, H; Qin, J; Quetschke, V; Quintero, E A; Quitzow-James, R; Raab, F J; Rabeling, D S; Radkins, H; Raffai, P; Raja, S; Rakhmanov, M; Rapagnani, P; Raymond, V; Razzano, M; Re, V; Read, J; Reed, C M; Regimbau, T; Rei, L; Reid, S; Reitze, D H; Rew, H; Reyes, S D; Ricci, F; Riles, K; Robertson, N A; Robie, R; Robinet, F; Rocchi, A; Rolland, L; Rollins, J G; Roma, V J; Romano, R; Romanov, G; Romie, J H; Rosińska, D; Rowan, S; Rüdiger, A; Ruggi, P; Ryan, K; Sachdev, S; Sadecki, T; Sadeghian, L; Salconi, L; Saleem, M; Salemi, F; Samajdar, A; Sammut, L; Sanchez, E J; Sandberg, V; Sandeen, B; Sanders, J R; Sassolas, B; Sathyaprakash, B S; Saulson, P R; Sauter, O; Savage, R L; Sawadsky, A; Schale, P; Schilling, R; Schmidt, J; Schmidt, P; Schnabel, R; Schofield, R M S; Schönbeck, A; Schreiber, E; Schuette, D; Schutz, B F; Scott, J; Scott, S M; Sellers, D; Sengupta, A S; Sentenac, D; Sequino, V; Sergeev, A; Serna, G; Setyawati, Y; Sevigny, A; Shaddock, D A; Shah, S; Shahriar, M S; Shaltev, M; Shao, Z; Shapiro, B; Shawhan, P; Sheperd, A; Shoemaker, D H; Shoemaker, D M; Siellez, K; Siemens, X; Sigg, D; Silva, A D; Simakov, D; Singer, A; Singer, L P; Singh, A; Singh, R; Singhal, A; Sintes, A M; Slagmolen, B J J; Smith, J R; Smith, N D; Smith, R J E; Son, E J; Sorazu, B; Sorrentino, F; Souradeep, T; Srivastava, A K; Staley, A; Steinke, M; Steinlechner, J; Steinlechner, S; Steinmeyer, D; Stephens, B C; Stone, R; Strain, K A; Straniero, N; Stratta, G; Strauss, N A; Strigin, S; Sturani, R; Stuver, A L; Summerscales, T Z; Sun, L; Sutton, P J; Swinkels, B L; Szczepańczyk, M J; Tacca, M; Talukder, D; Tanner, D B; Tápai, M; Tarabrin, S P; Taracchini, A; Taylor, R; Theeg, T; Thirugnanasambandam, M P; Thomas, E G; Thomas, M; Thomas, P; Thorne, K A; Thorne, K S; Thrane, E; Tiwari, S; Tiwari, V; Tokmakov, K V; Tomlinson, C; Tonelli, M; Torres, C V; Torrie, C I; Töyrä, D; Travasso, F; Traylor, G; Trifirò, D; Tringali, M C; Trozzo, L; Tse, M; Turconi, M; Tuyenbayev, D; Ugolini, D; Unnikrishnan, C S; Urban, A L; Usman, S A; Vahlbruch, H; Vajente, G; Valdes, G; Vallisneri, M; van Bakel, N; van Beuzekom, M; van den Brand, J F J; Van Den Broeck, C; Vander-Hyde, D C; van der Schaaf, L; van Heijningen, J V; van Veggel, A A; Vardaro, M; Vass, S; Vasúth, M; Vaulin, R; Vecchio, A; Vedovato, G; Veitch, J; Veitch, P J; Venkateswara, K; Verkindt, D; Vetrano, F; Viceré, A; Vinciguerra, S; Vine, D J; Vinet, J-Y; Vitale, S; Vo, T; Vocca, H; Vorvick, C; Voss, D; Vousden, W D; Vyatchanin, S P; Wade, A R; Wade, L E; Wade, M; Walker, M; Wallace, L; Walsh, S; Wang, G; Wang, H; Wang, M; Wang, X; Wang, Y; Ward, R L; Warner, J; Was, M; Weaver, B; Wei, L-W; Weinert, M; Weinstein, A J; Weiss, R; Welborn, T; Wen, L; Weßels, P; Westphal, T; Wette, K; Whelan, J T; White, D J; Whiting, B F; Williams, D; Williams, R D; Williamson, A R; Willis, J L; Willke, B; Wimmer, M H; Winkler, W; Wipf, C C; Wittel, H; Woan, G; Worden, J; Wright, J L; Wu, G; Yablon, J; Yam, W; Yamamoto, H; Yancey, C C; Yap, M J; Yu, H; Yvert, M; Zadrożny, A; Zangrando, L; Zanolin, M; Zendri, J-P; Zevin, M; Zhang, F; Zhang, L; Zhang, M; Zhang, Y; Zhao, C; Zhou, M; Zhou, Z; Zhu, X J; Zucker, M E; Zuraw, S E; Zweizig, J; Boyle, M; Campanelli, M; Hemberger, D A; Kidder, L E; Ossokine, S; Scheel, M A; Szilagyi, B; Teukolsky, S; Zlochower, Y

2016-06-03

The LIGO detection of GW150914 provides an unprecedented opportunity to study the two-body motion of a compact-object binary in the large-velocity, highly nonlinear regime, and to witness the final merger of the binary and the excitation of uniquely relativistic modes of the gravitational field. We carry out several investigations to determine whether GW150914 is consistent with a binary black-hole merger in general relativity. We find that the final remnant's mass and spin, as determined from the low-frequency (inspiral) and high-frequency (postinspiral) phases of the signal, are mutually consistent with the binary black-hole solution in general relativity. Furthermore, the data following the peak of GW150914 are consistent with the least-damped quasinormal mode inferred from the mass and spin of the remnant black hole. By using waveform models that allow for parametrized general-relativity violations during the inspiral and merger phases, we perform quantitative tests on the gravitational-wave phase in the dynamical regime and we determine the first empirical bounds on several high-order post-Newtonian coefficients. We constrain the graviton Compton wavelength, assuming that gravitons are dispersed in vacuum in the same way as particles with mass, obtaining a 90%-confidence lower bound of 10^{13}  km. In conclusion, within our statistical uncertainties, we find no evidence for violations of general relativity in the genuinely strong-field regime of gravity.

Dimensional Analysis and General Relativity

Science.gov (United States)

Lovatt, Ian

2009-01-01

Newton's law of gravitation is a central topic in the first-year physics curriculum. A lecturer can go beyond the physical details and use the history of gravitation to discuss the development of scientific ideas; unfortunately, the most recent chapter in this history, general relativity, is not covered in first-year courses. This paper discusses…

Strains in general relativity

International Nuclear Information System (INIS)

Bini, Donato; Felice, Fernando de; Geralico, Andrea

2006-01-01

The definition of relative accelerations and strains among a set of comoving particles is studied in connection with the geometric properties of the frame adapted to a 'fiducial observer'. We find that a relativistically complete and correct definition of strains must take into account the transport law of the chosen spatial triad along the observer's congruence. We use special congruences of (accelerated) test particles in some familiar spacetimes to elucidate such a point. The celebrated idea of Szekeres' compass of inertia, arising when studying geodesic deviation among a set of free-falling particles, is here generalized to the case of accelerated particles. In doing so we have naturally contributed to the theory of relativistic gravity gradiometer. Moreover, our analysis was made in an observer-dependent form, a fact that would be very useful when thinking about general relativistic tests on space stations orbiting compact objects like black holes and also in other interesting gravitational situations

Concept Generation for Design Creativity A Systematized Theory and Methodology

CERN Document Server

Taura, Toshiharu

2013-01-01

The concept generation process seems like an intuitional thought: difficult to capture and perform, although everyone is capable of it. It is not an analytical process but a synthetic process which has yet to be clarified. Furthermore, new research methods for investigating the concept generation process—a very difficult task since the concept generation process is driven by inner feelings deeply etched in the mind—are necessary to establish its theory and methodology.  Concept Generation for Design Creativity—A Systematized Theory and Methodology presents the concept generation process both theoretically and methodologically. Theoretically, the concept generation process is discussed by comparing metaphor, abduction, and General Design Theory from the perspective of similarities and dissimilarities. Property mapping, concept blending, and concept integration in thematic relation have been explained methodologically. So far, these theories and methods have been discussed independently, and the relation...

Quantum theory and Einstein's general relativity

International Nuclear Information System (INIS)

Borzeszkowski, H.H.v.; Treder, H.J.

1984-01-01

The paper concerns Einstein's general relativity, wave mechanics and the quantization of Einstein's gravitation equations. The principle of equivalence and its association with both wave mechanics and quantum gravity, is discussed. (U.K.)

Modeling of energy consumption and related GHG (greenhouse gas) intensity and emissions in Europe using general regression neural networks

International Nuclear Information System (INIS)

Antanasijević, Davor; Pocajt, Viktor; Ristić, Mirjana; Perić-Grujić, Aleksandra

2015-01-01

This paper presents a new approach for the estimation of energy-related GHG (greenhouse gas) emissions at the national level that combines the simplicity of the concept of GHG intensity and the generalization capabilities of ANNs (artificial neural networks). The main objectives of this work includes the determination of the accuracy of a GRNN (general regression neural network) model applied for the prediction of EC (energy consumption) and GHG intensity of energy consumption, utilizing general country statistics as inputs, as well as analysis of the accuracy of energy-related GHG emissions obtained by multiplying the two aforementioned outputs. The models were developed using historical data from the period 2004–2012, for a set of 26 European countries (EU Members). The obtained results demonstrate that the GRNN GHG intensity model provides a more accurate prediction, with the MAPE (mean absolute percentage error) of 4.5%, than tested MLR (multiple linear regression) and second-order and third-order non-linear MPR (multiple polynomial regression) models. Also, the GRNN EC model has high accuracy (MAPE = 3.6%), and therefore both GRNN models and the proposed approach can be considered as suitable for the calculation of GHG emissions. The energy-related predicted GHG emissions were very similar to the actual GHG emissions of EU Members (MAPE = 6.4%). - Highlights: • ANN modeling of GHG intensity of energy consumption is presented. • ANN modeling of energy consumption at the national level is presented. • GHG intensity concept was used for the estimation of energy-related GHG emissions. • The ANN models provide better results in comparison with conventional models. • Forecast of GHG emissions for 26 countries was made successfully with MAPE of 6.4%

Adiposopathy, metabolic syndrome, quantum physics, general relativity, chaos and the Theory of Everything.

Science.gov (United States)

Bays, Harold

2005-05-01

Excessive fat (adiposity) and dysfunctional fat (adiposopathy) constitute the most common worldwide epidemics of our time -- and perhaps of all time. Ongoing efforts to explain how the micro (adipocyte) and macro (body organ) biologic systems interact through function and dysfunction in promoting Type 2 diabetes mellitus, hypertension and dyslipidemia are not unlike the mechanistic and philosophical thinking processes involved in reconciling the micro (quantum physics) and macro (general relativity) theories in physics. Currently, the term metabolic syndrome refers to a constellation of consequences often associated with excess body fat and is an attempt to unify the associations known to exist between the four fundamental metabolic diseases of obesity, hyperglycemia (including Type 2 diabetes mellitus), hypertension and dyslipidemia. However, the association of adiposity with these metabolic disorders is not absolute and the metabolic syndrome does not describe underlying causality, nor does the metabolic syndrome necessarily reflect any reasonably related pathophysiologic process. Just as with quantum physics, general relativity and the four fundamental forces of the universe, the lack of an adequate unifying theory of micro causality and macro consequence is unsatisfying, and in medicine, impairs the development of agents that may globally improve both obesity and obesity-related metabolic disease. Emerging scientific and clinical evidence strongly supports the novel concept that it is not adiposity alone, but rather it is adiposopathy that is the underlying cause of most cases of Type 2 diabetes mellitus, hypertension and dyslipidemia. Adiposopathy is a plausible Theory of Everything for mankind's greatest metabolic epidemics.

Einstein and General Relativity: Historical Perspectives.

Science.gov (United States)

Chandrasekhar, S.

1979-01-01

This paper presented in the 1978 Oppenheimer Memorial Lecture at Los Alamos Scientific Laboratories on August 17, 1978, discusses Einstein's contributions to physics, in particular, his discovery of the general theory of relativity. (HM)

Black hole dynamics in general relativity

Indian Academy of Sciences (India)

Abstract. Basic features of dynamical black holes in full, non-linear general relativity are summarized in a pedagogical fashion. Qualitative properties of the evolution of various horizons follow directly from the celebrated Raychaudhuri equation.

General formulation of standard model the standard model is in need of new concepts

International Nuclear Information System (INIS)

Khodjaev, L.Sh.

2001-01-01

The phenomenological basis for formulation of the Standard Model has been reviewed. The Standard Model based on the fundamental postulates has been formulated. The concept of the fundamental symmetries has been introduced: To look for not fundamental particles but fundamental symmetries. By searching of more general theory it is natural to search first of all global symmetries and than to learn consequence connected with the localisation of this global symmetries like wise of the standard Model

Concept analysis of risk in relation to coronary heart disease among Filipino-Americans.

Science.gov (United States)

Dalusung-Angosta, Alona

2010-01-01

To analyze the concept of risk in relation to coronary heart disease (CHD) among Filipino-Americans (FAs) and provide a new definition of risk. Published literature. This concept analysis provided a new meaning of risk in relation to CHD among FAs and shed light on further understanding of risk. Risk has been laced with negativity in health care, but based on the current literature, risk can be conceptualized in a positive perspective, especially in the area of chronic health disease such as CHD. However, further research is needed in the conceptualization of risk related to CHD for consistency, adequacy, and meaning. © 2010 Wiley Periodicals, Inc.

Derivation of Einstein-Cartan theory from general relativity

Science.gov (United States)

Petti, Richard

2015-04-01

General relativity cannot describe exchange of classical intrinsic angular momentum and orbital angular momentum. Einstein-Cartan theory fixes this problem in the least invasive way. In the late 20th century, the consensus view was that Einstein-Cartan theory requires inclusion of torsion without adequate justification, it has no empirical support (though it doesn't conflict with any known evidence), it solves no important problem, and it complicates gravitational theory with no compensating benefit. In 1986 the author published a derivation of Einstein-Cartan theory from general relativity, with no additional assumptions or parameters. Starting without torsion, Poincaré symmetry, classical or quantum spin, or spinors, it derives torsion and its relation to spin from a continuum limit of general relativistic solutions. The present work makes the case that this computation, combined with supporting arguments, constitutes a derivation of Einstein-Cartan theory from general relativity, not just a plausibility argument. This paper adds more and simpler explanations, more computational details, correction of a factor of 2, discussion of limitations of the derivation, and discussion of some areas of gravitational research where Einstein-Cartan theory is relevant.

Relativity: An Introduction to Special and General Relativity, 3rd edn

International Nuclear Information System (INIS)

Rendall, Alan

2004-01-01

This book is concerned with mathematical topics related to general relativity. Chapters 1-6 are expositions of a number of parts of mathematics which are important for relativists. The main subjects covered are linear algebra, general topology, manifolds, Lie groups and, in particular detail, the Lorentz group. Chapters 7-13 analyse aspects of the geometrical structure of spacetimes. They focus on symmetries of various types and on properties of curvature. Subjects covered include the Petrov classification, holonomy groups, the relation between metric and curvature, affine vector fields, conformal symmetries, projective symmetries and curvature collineations. This part of the book is a treatise on the (mainly local) geometry of four-dimensional Lorentz manifolds, with attention to energy-momentum tensors of interest in general relativity. In the first six chapters the author has concentrated on giving definitions and statements of theorems, the proofs being left to the references that are quoted. He has clearly put much effort into producing a very smooth exposition which is easy to follow and has succeeded in giving us a readable and informative account of the mathematics covered. At the same time mathematical rigour is strictly observed. He also takes the time to carefully discuss many of the subtleties which arise. This part of the book has the character of a textbook suitable for students of general relativity but experienced researchers will also find it a useful reference and are likely to come across interesting facts they have not met elsewhere. The remaining chapters are more like a research monograph and are influenced by the author's own research interests. More proofs are included. Much of the material in this part will be of interest to a narrower audience of relativists than that of the first part. It should, however, be of interest to those working on exact solutions of the Einstein equations and related topics. It is also the case that most

Unsupervised Learning and Generalization

DEFF Research Database (Denmark)

Hansen, Lars Kai; Larsen, Jan

1996-01-01

The concept of generalization is defined for a general class of unsupervised learning machines. The generalization error is a straightforward extension of the corresponding concept for supervised learning, and may be estimated empirically using a test set or by statistical means-in close analogy ...... with supervised learning. The empirical and analytical estimates are compared for principal component analysis and for K-means clustering based density estimation......The concept of generalization is defined for a general class of unsupervised learning machines. The generalization error is a straightforward extension of the corresponding concept for supervised learning, and may be estimated empirically using a test set or by statistical means-in close analogy...

General and special education teachers' relations within teamwork ...

African Journals Online (AJOL)

and instruction, assessment and evaluation, and classroom management and behavior. Typically, the ... teaching techniques and learning processes. ... general objective of this research is to establish the relations of general and special.

Towards a concept of food-related life style

DEFF Research Database (Denmark)

Grunert, Klaus G.

Life style has become popular in explaining food choice. In this paper the way life style studies are usually conducted is criticized based on a) that the methods lack a theoretical foundation, b) that the statistical methods are questionable, and c)that the explanatory power with regard to food...... choice remains to be demonstrated. A cognitive deductive approach is presented as a theoretically more well-founded alternative. It defines life style as the system of cognitive categories, scripts, and their associations, which relate a set of products to a set of values. A concept of food-related life...... style should hence contain elements like shopping scripts, meal preparation scripts, desired higher-order food attributes, food usage situations, and desired consequences of food products....

General relativity and dark matter

International Nuclear Information System (INIS)

Pestov, A.B.

1993-01-01

It is shown that from the first principles of General Relativity it follows that there exists a new type of interactions which are tightly connected with the gravitational interactions. New particles representing a new form of interactions do not interact electromagnetically, strongly and weakly with the known elementary particles. Physics of the new particles is defined by the Planck scales. (author.). 9 refs

Quantum information and general relativity

OpenAIRE

Peres, Asher

2004-01-01

The Einstein-Podolsky-Rosen paradox (1935) is reexamined in the light of Shannon's information theory (1948). The EPR argument did not take into account that the observers' information was localized, like any other physical object. General relativity introduces new problems: there are horizons which act as one-way membranes for the propagation of quantum information, in particular black holes which act like sinks.

Quantum information and general relativity

Science.gov (United States)

Peres, A.

2004-11-01

The Einstein-Podolsky-Rosen paradox (1935) is reexamined in the light of Shannon's information theory (1948). The EPR argument did not take into account that the observers' information was localized, like any other physical object. General relativity introduces new problems: there are horizons which act as on-way membranes for the propagation of quantum information, in particular black holes which act like sinks.

Modified General Relativity and Cosmology

Science.gov (United States)

Abdel-Rahman, A.-M. M.

1997-10-01

Aspects of the modified general relativity theory of Rastall, Al-Rawaf and Taha are discussed in both the radiation- and matter-dominated flat cosmological models. A nucleosynthesis constraint on the theory's free parameter is obtained and the implication for the age of the Universe is discussed. The consistency of the modified matter- dominated model with the neoclassical cosmological tests is demonstrated.

Algebraic computing in general relativity

International Nuclear Information System (INIS)

D'Inverno, R.A.

1975-01-01

The purpose of this paper is to bring to the attention of potential users the existence of algebraic computing systems, and to illustrate their use by reviewing a number of problems for which such a system has been successfully used in General Relativity. In addition, some remarks are included which may be of help in the future design of these systems. (author)

Conformal methods in general relativity

CERN Document Server

Valiente Kroon, Juan A

2016-01-01

This book offers a systematic exposition of conformal methods and how they can be used to study the global properties of solutions to the equations of Einstein's theory of gravity. It shows that combining these ideas with differential geometry can elucidate the existence and stability of the basic solutions of the theory. Introducing the differential geometric, spinorial and PDE background required to gain a deep understanding of conformal methods, this text provides an accessible account of key results in mathematical relativity over the last thirty years, including the stability of de Sitter and Minkowski spacetimes. For graduate students and researchers, this self-contained account includes useful visual models to help the reader grasp abstract concepts and a list of further reading, making this the perfect reference companion on the topic.

O(3)-invariant tunneling in general relativity

International Nuclear Information System (INIS)

Berezin, V.A.; Tkachev, I.I.; Kuzmin, V.A.; AN SSSR, Moscow. Inst. Yadernykh Issledovanij)

1987-12-01

We derived a general formula for the action for any O(3)-invariant tunneling processes in false vacuum decay in general relativity. The general classification of the bubble Euclidean trajectories is elaborated and explicit expressions for bounces for some processes like the vacuum creation of a double bubble, in particular in the vicinity of a black hole; the subbarrier creation of the Einstein-Rosen bridge, creation from nothing of two Minkowski worlds connected by a shell etc., are given. (orig.)

Prosthodontic decision-making relating to dentitions with compromised molars: the perspective of Swedish General Dental Practitioners.

Science.gov (United States)

Korduner, E-K; Collin Bagewitz, I; Vult von Steyern, P; Wolf, E

2016-12-01

The aim of this investigation was to study the clinical prosthodontic decision-making process relating to dentitions with compromised molars among Swedish general dental practitioners (GDPs). Eleven Swedish GDPs were purposively selected, and all agreed to participate. Then, in-depth, semi-structured interviews were conducted and covered treatment considerations concerning two authentic patient cases, initially with complete dental arches, and later, a final treatment based on a shortened dental arch (SDA) was discussed. The cases involved patients with compromised teeth situated mainly in the molar regions. One patient suffered from extensive caries and the other from severe periodontal disease. Qualitative content analysis was used to analyse the data. In the systematic analysis, two main categories were identified: holistic and functional approach. Among the interviewed GDPs, focus was put on patients' needs, background history and motivation for treatment as well as the preservation of molar support. Within the limitations of this study, the following can be concluded: keeping a dental arch with molars seems to be important to Swedish general dental practitioners. The SDA concept does not seem to have a substantial impact on the prosthodontic decision-making relating to dentitions with compromised molars. The dentist's experiences, as well as colleagues' or consulting specialist advice together with aetiological factors and the patient's individual situation, influence the decision-making more than the SDA concept. The conflicting results in the prosthetic decision-making process concerning the relevance of age and the need for molar support need further investigation, for example based on decisions made in the dentist's own clinical practice. © 2016 John Wiley & Sons Ltd.

Hallucinations and related concepts – their conceptual background

Directory of Open Access Journals (Sweden)

Diogo eTelles-Correia

2015-07-01

Full Text Available Prior to the 17th century, the experiences we now name hallucinations or others alike were valued within a cultural context, they could bring meaning to the subject or the world. From mid-17th to 18th centuries, they acquire a medical quality in mental and organic illnesses. However, the term was only fully integrated in psychiatry by Esquirol in the 18th-19th centuries. By then, a controversy begins on whether hallucinations have a perceptual or intellectual origin. Esquirol favours the intellectual origin, describing them as an involuntary exercise of memory and imagination.By the twentieth century, some authors maintain that hallucinations are a form of delusion (Ey, while others describe them as a change in perception (Jaspers, Fish. A more integrated perspectives like those proposed by Alonso Fernandez and Luque, highlights the heterogeneity of hallucinations and the multiplicity of their types and causes.The terms pseudohallucination, illusion and hallucinosis are grafted into the concept of hallucination. Since its introduction the term pseudohallucination has been used with different meanings. The major characteristics that we found associated with pseudohallucinations were ‘lack of objectivity’ and ‘presence of insight’ (differing from hallucinations. Illusions are unanimously taken as distortions of real objects. Hallucinosis, first described in the context of alcohol consumption, is generally considered egodystonic, in which insight is preserved.These and other controversial aspects regarding the evolution of the term hallucination and all its derivative concepts are discussed in this paper.

Relativity: Special, General, and Cosmological

International Nuclear Information System (INIS)

Ellis, G F R

2005-01-01

Wolfgang Rindler is known as a writer of exceptional clarity. This quality is evident in this book as it explores in depth first special relativity, then general relativity, and finally relativistic cosmology. He bases his writing in the fundamental underlying ideas and principles that so successfully guided Einstein in his work, clarifying their nature and implications in an illuminating way with many examples. The usual suspects are there: the relativity principle and equivalence principle, the abolishing of absolute space, invariance of the speed of light, analytic and geometric representations of the Lorentz transformation, its kinematic and dynamic consequences, relativistic optics, Minkowski spacetime, energy and momentum conservation, and the Compton effect. Particularly useful is the emphasis on the unity of the whole: for example (p 63) that the kinematic effect of length shortening must imply a corresponding detailed mechanical explanation of that shortening. The tensor formulation of Maxwell's equations leads to the transformation properties of the electromagnetic field and consequent elegant derivation of the field of an infinite straight current; in this case, relativity is important even for slowly moving charges because an ordinary current moves a very big charge (p 151). General relativity is systematically introduced in stages, starting with curved spaces and moving on through static and stationary spacetimes, geodesics, and tensor calculus to the field equations. A considerable strength of the book is the careful detailed examination of the local and global geometry of the major significant solutions of the equations: the Schwarzschild spacetime and its Kruskal extension, plane gravitational waves, de sitter and anti-de Sitter spacetimes, and Robertson-Walker cosmologies. The latter includes a clear presentation of the dust and radiation model dynamics for the variety of possible cases, a detailed examination of observational relations, and

Identifying biological concepts from a protein-related corpus with a probabilistic topic model

Directory of Open Access Journals (Sweden)

Lu Xinghua

2006-02-01

Full Text Available Abstract Background Biomedical literature, e.g., MEDLINE, contains a wealth of knowledge regarding functions of proteins. Major recurring biological concepts within such text corpora represent the domains of this body of knowledge. The goal of this research is to identify the major biological topics/concepts from a corpus of protein-related MEDLINE© titles and abstracts by applying a probabilistic topic model. Results The latent Dirichlet allocation (LDA model was applied to the corpus. Based on the Bayesian model selection, 300 major topics were extracted from the corpus. The majority of identified topics/concepts was found to be semantically coherent and most represented biological objects or concepts. The identified topics/concepts were further mapped to the controlled vocabulary of the Gene Ontology (GO terms based on mutual information. Conclusion The major and recurring biological concepts within a collection of MEDLINE documents can be extracted by the LDA model. The identified topics/concepts provide parsimonious and semantically-enriched representation of the texts in a semantic space with reduced dimensionality and can be used to index text.

The Self-Education Concept: General Notions and Structure

Directory of Open Access Journals (Sweden)

I. F. Medvedev

2012-01-01

Full Text Available The paper is devoted to the developing approach to students’ training based on the concept of self-education. The aim of the study is defined as developing the theoretical basis for self-education at Higher School. The initial research positions are derived from the methodology approach; the terminology analysis is being applied for defining the conceptual field of the research; the systematic approach gives the ground for the integral consideration of the self-education issue. The author specifies the categories and attributes of the self-education concept, its methodology basis, as well as the essence and practical conclusions, including the didactic conformities, principles and method requirements. The content of the concept in question substantiates organizational methodic arrangements of educational process including the complex of procedures for working out the normative documents, planning and organizing students’ self-educational activity, application of modern educational technologies. The re- search findings can be used by scientists, lectures, teaching staff and post-graduates in the process of implementing the innovation education technologies at Higher School. 

Proof of Concept: Model Based Bionic Muscle with Hyperbolic Force-Velocity Relation

Directory of Open Access Journals (Sweden)

D. F. B. Haeufle

2012-01-01

Full Text Available Recently, the hyperbolic Hill-type force-velocity relation was derived from basic physical components. It was shown that a contractile element CE consisting of a mechanical energy source (active element AE, a parallel damper element (PDE, and a serial element (SE exhibits operating points with hyperbolic force-velocity dependency. In this paper, a technical proof of this concept was presented. AE and PDE were implemented as electric motors, SE as a mechanical spring. The force-velocity relation of this artificial CE was determined in quick release experiments. The CE exhibited hyperbolic force-velocity dependency. This proof of concept can be seen as a well-founded starting point for the development of Hill-type artificial muscles.

Obsessive-compulsive disorder and its related disorders: a reappraisal of obsessive-compulsive spectrum concepts.

Science.gov (United States)

Murphy, Dennis L; Timpano, Kiara R; Wheaton, Michael G; Greenberg, Benjamin D; Miguel, Euripedes C

2010-01-01

Obsessive-compulsive disorder (OCD) is a clinical syndrome whose hallmarks are excessive, anxiety-evoking thoughts and compulsive behaviors that are generally recognized as unreasonable, but which cause significant distress and impairment. When these are the exclusive symptoms, they constitute uncomplicated OCD. OCD may also occur in the context of other neuropsychiatric disorders, most commonly other anxiety and mood disorders. The question remains as to whether these combinations of disorders should be regarded as independent, cooccurring disorders or as different manifestations of an incompletely understood constellation of OCD spectrum disorders with a common etiology. Additional considerations are given here to two potential etiology-based subgroups: (i) an environmentally based group in which OCD occurs following apparent causal events such as streptococcal infections, brain injury, or atypical neuroleptic treatment; and (ii) a genomically based group in which OCD is related to chromosomal anomalies or specific genes. Considering the status of current research, the concept of OCD and OCD-related spectrum conditions seems fluid in 2010, and in need of ongoing reappraisal.

Concepts of magnetospheric convection

International Nuclear Information System (INIS)

Vasyliunas, V.M.

1975-01-01

Magnetospheric physics, which grew out of attempts to understand the space environment of the Earth, is becoming increasingly applicable to other systems in the Universe. Among the planets, in addition to the Earth, Jupiter, Mercury, Mars and (in a somewhat different way) Venus are now known to have magnetospheres. The magnetospheres of pulsars have been regarded as an essential part of the pulsar phenomenon. Other astrophysical systems, such as supernova remnant shells or magnetic stars and binary star systems, may be describable as magnetospheres. The major concepts of magnetospheric physics thus need to be formulated in a general way not restricted to the geophysical context in which they may have originated. Magnetospheric convection has been one of the most important and fruitful concepts in the study of the Earth's magnetosphere. This paper describes the basic theoretical notions of convection in a manner applicable to magnetospheres generally and discusses the relative importance of convective corotational motions, with particular reference to the comparison of the Earth and Jupiter. (Auth.)

70 years of the general theory of relativity

International Nuclear Information System (INIS)

Castro Diaz-Balart, F.; Cabezas Solorzano, R.

1986-06-01

In view of the 70th anniversary of the discovery of the General Theory of Relativity, an analysis was made of the special and general theories. The basic postulates, their consequences in the formulation of the theories, the main results, some aspects related to the experimental verification and its applications are presented, as are some elements of the mathematical formalism of the theories, to facilitate the logical interrelationships between its results and consequences. (author)

On the relation of the theoretical foundations of quantum theory and general relativity theory

International Nuclear Information System (INIS)

Kober, Martin

2010-01-01

The specific content of the present thesis is presented in the following way. First the most important contents of quantum theory and general relativity theory are presented. In connection with the general relativity theory the mathematical property of the diffeomorphism invariance plays the deciding role, while concerning the quantum theory starting from the Copenhagen interpretation first the measurement problem is treated, before basing on the analysis of concrete phenomena and the mathematical apparatus of quantum theory the nonlocality is brought into focus as an important property. This means that both theories suggest a relationalistic view of the nature of the space. This analysis of the theoretical foundations of quantum theory and general relativity theory in relation to the nature of the space obtains only under inclusion of Kant's philosophy and his analysis of the terms space and time as fundamental forms of perception its full persuasive power. Then von Weizsaeckers quantum theory of the ur-alternatives is presented. Finally attempts are made to apply the obtained knowledge to the question of the quantum-theoretical formulation of general relativity theory.

Engagement and burnout at work, and related concepts for the 6th EWCS

NARCIS (Netherlands)

Houtman, I.L.D.; Schaufeli, W.B.

2017-01-01

Work engagement in Europe: an ultra-short work engagement scale and its relation with related concepts. Research and policy attention on work-related stress, mental health and well-being has increased, both in the international scientific literature as well as in society. Within the latter sphere,

Einstein algebras and general relativity

International Nuclear Information System (INIS)

Heller, M.

1992-01-01

A purely algebraic structure called an Einstein algebra is defined in such a way that every spacetime satisfying Einstein's equations is an Einstein algebra but not vice versa. The Gelfand representation of Einstein algebras is defined, and two of its subrepresentations are discussed. One of them is equivalent to the global formulation of the standard theory of general relativity; the other one leads to a more general theory of gravitation which, in particular, includes so-called regular singularities. In order to include other types of singularities one must change to sheaves of Einstein algebras. They are defined and briefly discussed. As a test of the proposed method, the sheaf of Einstein algebras corresponding to the space-time of a straight cosmic string with quasiregular singularity is constructed. 22 refs

General relativity and gravitation a centennial perspective

CERN Document Server

Berger, Beverly K; Isenberg, James; MacCallum, Malcolm

2015-01-01

Explore spectacular advances in cosmology, relativistic astrophysics, gravitational wave science, mathematics, computational science, and the interface of gravitation and quantum physics with this unique celebration of the centennial of Einstein's discovery of general relativity. Twelve comprehensive and in-depth reviews, written by a team of world-leading international experts, together present an up-to-date overview of key topics at the frontiers of these areas, with particular emphasis on the significant developments of the last three decades. Interconnections with other fields of research are also highlighted, making this an invaluable resource for both new and experienced researchers. Commissioned by the International Society on General Relativity and Gravitation, and including accessible introductions to cutting-edge topics, ample references to original research papers, and informative colour figures, this is a definitive reference for researchers and graduate students in cosmology, relativity, and grav...

Development of Einstein's general theory of relativity

International Nuclear Information System (INIS)

Datta, B.K.

1980-01-01

Starting from Poincare's Lorentz-invariant theory of gravity formulated in 1906, development of Einstein's general theory of relativity during 1906-1916 is discussed. Three stages in this development are recognised. In the first stage during 1907-1914, Einstein tried to extend the relativity principle of uniform motion to the frames in non-uniform motion. For this purpose, he introduced the principle of equivalence which made it possible to calculate the effect of homogeneous gravitational field on arbitrary physical processes. During the second stage comprising years 1912-1914 overlapping the first stage, Einstein and Grossmann were struggling to translate physical postulates into the language of the absolute differential calculus. In the period 1915-1916, Einstein formulated the field equations of general relativity. While discussing these developmental stages, theories of gravitation formulated by Abraham, Nordstroem and Mie are also discussed. (M.G.B.)

Generalized uncertainty relations and characteristic invariants for the multimode states

International Nuclear Information System (INIS)

Sudarshan, E.C.G.; Chiu, C.B.; Bhamathi, G.

1995-01-01

The close relationship between the zero-point energy, the uncertainty relation, coherent states, squeezed states, and correlated states for one mode is investigated. This group theoretic perspective of the problem enables the parametrization and identification of their multimode generalization. A simple and efficient method of determining the canonical structure of the generalized correlated states is presented. Implication of canonical commutation relations for correlations are not exhausted by the Heisenberg uncertainty relation, not even by the Schroedinger-Robertson uncertainty inequality, but there are relations in the multimode case that are the generalization of the Schroedinger-Robertson relation

Why Multicollinearity Matters: A Reexamination of Relations Between Self-Efficacy, Self-Concept, and Achievement

Science.gov (United States)

Marsh, Herbert W.; Dowson, Martin; Pietsch, James; Walker, Richard

2004-01-01

Multicollinearity is a well-known general problem, but it also seriously threatens valid interpretations in structural equation models. Illustrating this problem, J. Pietsch, R. Walker, and E. Chapman (2003) found paths leading to achievement were apparently much larger for self-efficacy (.55) than self-concept (-.05), suggesting--erroneously, as…

Generalized hypervirial and Blanchard's recurrence relations for radial matrix elements

International Nuclear Information System (INIS)

Dong Shihai; Chen Changyuan; Lozada-Cassou, M

2005-01-01

Based on the Hamiltonian identity, we propose a generalized expression of the second hypervirial for an arbitrary central potential wavefunction in arbitrary dimensions D. We demonstrate that the new proposed second hypervirial formula is very powerful in deriving the general Blanchard's and Kramers' recurrence relations among the radial matrix elements. As their useful and important applications, we derive all general Blanchard's and Kramers' recurrence relations and some identities for the Coulomb-like potential, harmonic oscillator and Kratzer oscillator. The recurrence relation and identity between the exponential functions and the powers of the radial function are established for the Morse potential. The corresponding general Blanchard's and Kramers' recurrence relations in 2D are also briefly studied

Nonlinear generalization of special relativity

International Nuclear Information System (INIS)

Winterberg, F.

1985-01-01

In Poincares axiomatic formulation special relativity is a derived consequence of a true Lorentz contraction, for a rod in absolute motion through a substratum. Furthermore, Lorentz had shown that the rod contraction can be understood by an inverse square law interaction and therefore special relativity derived from more fundamental principles. The derivation by Lorentz shows that the root of the divergence problems is the singular inverse square law. By replacing the inverse square law with a regular one through the introduction of a finite length, the author has succeeded in deriving a nonlinear generalization of special relativity which eliminates all infinities. Besides the relative velocities, these nonlinear transformation equations also contain absolute velocities against a substratum, but in the limit of small energies they go over into the linear Lorentz transformations. Depending on the smallness of the fundamental length, departures from special relativity can be observed only at very high energies. The theorem that the velocity of light is the same in all reference systems still holds and likewise the conservation laws for energy and momentum

Bubble collisions in general relativity

International Nuclear Information System (INIS)

Siklos, S.T.C.; Wu, Z.C.; University of Science and Technology of China, Hofei, Anhwei)

1983-01-01

The collision of two bubbles of true vacuum in a background of false vacuum is considered in the context of General Relativity. It is found that in the thin wall approximation, the problem, can be solved exactly. The region to the future of the collision is described by the pseudo-Schwarzschild de Sitter metric. The parameters in this metric are found by solving the junction conditions at each collision. (author)

Quantum information and general relativity

International Nuclear Information System (INIS)

Peres, A.

2004-01-01

The Einstein-Podolsky-Rosen paradox (1935) is reexamined in the light of Shannon's information theory (1948). The EPR argument did not take into account that the observers' information was localized, like any other physical object. General relativity introduces new problems: there are horizons which act as on-way membranes for the propagation of quantum information, in particular black holes which act like sinks. (Abstract Copyright [2004], Wiley Periodicals, Inc.)

Using CAMAL for algebraic computations in general relativity

International Nuclear Information System (INIS)

Fitch, J.P.

1979-01-01

CAMAL is a collection of computer algebra systems developed in Cambridge, England for use mainly in theoretical physics. One of these was designed originally for general relativity calculations, although it is often used in other fields. In a recent paper Cohen, Leringe, and Sundblad compared six systems for algebraic computations applied to general relativity available in Stockholm. Here similar information for CAMAL is given and by using the same tests CAMAL is added to the comparison. (author)

Generalized Disjunctions in (Infinitary) Structural Consequence Relations

Czech Academy of Sciences Publication Activity Database

Cintula, Petr; Noguera, C.

2012-01-01

Roč. 18, č. 3 (2012), s. 442-443 ISSN 1079-8986. [Logic Colloquium 2011. 11.07.2011-16.07.2011, Barcelona] R&D Projects: GA MŠk(CZ) 1M0545 Institutional research plan: CEZ:AV0Z10300504 Keywords : Abstract Algebraic Logic * Generalized disjunction * Proof by cases properties * Consequence relations Subject RIV: BA - General Mathematics http://www.math.ucla.edu/~asl/bsl/1803- toc .htm

BOOK REVIEW: A First Course in General Relativity (Second Edition) A First Course in General Relativity (Second Edition)

Science.gov (United States)

Poisson, Eric

2010-05-01

A few years ago, in my review of Sean Carroll's book in Classical and Quantum Gravity [1], I wrote that while the 1970s was the decade of Weinberg [2] and Misner, Thorne and Wheeler [3], and while the eighties was the decade of Schutz [4] and Wald [5], the 2000s was clearly the decade of Hartle [6] and Carroll [7]. In my opinion, these books continue to stand out in the surprisingly dense crowd of introductory textbooks on general relativity. At the dawn of this new decade I look forward to see what fresh pedagogical insights will be produced next, and who will be revealed as the winners of the 2010s. It is, of course, much too early to tell, but Schutz is back, and he will set the standard just as he did back in 1985. This is the long-awaited second edition of his `First Course', a short, accessible, and very successful introduction to general relativity. The changes from the first edition are modest: Schutz wisely refrained from bloating the text with new topics, and limited himself to updating his discussion of gravitational-wave sources and detectors, neutron-star and black-hole astrophysics, and suggestions for further reading. Most importantly, he completely rewrote the chapter on cosmology, a topic that has evolved enormously since the first edition. The book begins in chapter 1 with a beautiful review of special relativity that emphasizes spacetime geometry and stays away from an algebraic approach based on the Lorentz transformation, which appears only later in the chapter. This is followed up in chapters 2 and 3 with an introduction to vector and tensor analysis in flat spacetime. The point of view is modern (tensors are defined as linear mapping of vectors and one-forms into real numbers) but the presentation is very accessible and avoids an overload of mathematical fine print. In chapter 4 the book introduces the spacetime description of fluids; it is here that the energy-momentum tensor makes its first appearance. The move to curved spacetime is

On semi star generalized closed sets in bitopological spaces.

Directory of Open Access Journals (Sweden)

K. Kannan

2010-07-01

Full Text Available K. Chandrasekhara Rao and K. Joseph [5] introduced the concepts of semi star generalized open sets and semi star generalized closed sets in a topological space. The same concept was extended to bitopological spaces by K. Chan-drasekhara Rao and K. Kannan [6,7]. In this paper, we continue the study of τ1τ2-s∗g closed sets inbitopology and we introduced the newly related concept of pairwise s∗g-continuous mappings. Also S∗GO-connectedness and S∗GO-compactness are introduced in bitopological spaces and some of their properties are established.

KALIMER design concept report

Energy Technology Data Exchange (ETDEWEB)

Park, Chang Kyu; Kim, Young Cheol; Kim, Young In; Kim, Young Gyun; Kim, Eui Kwang; Song, Hoon; Chung, Hyun Tai; Hwang, Woan; Nam, Cheol; Sub, Sim Yoon; Kim, Yeon Sik; Whan, Wim Myung; Min, Byung Tae; Yoo, Bong; Lee, Jae Han; Lee, Hyeong Yeon; Kim, Jong Bum; Koo, Gyeong Hoi; Ham, Chang Shik; Kwon, Kee Choon; Kim, Jung Taek; Park, Jae Chang; Lee, Jung Woon; Lee, Yong Hee; Kim, Chang Hwoi; Sim, Bong Shick; Hahn, Do Hee; Choi, Jong Hyeun; Kwon, Sang Woon

1997-07-01

KAERI is working for the development of KALIMER and work is being done for methodology development, experimental facility set up and design concept development. The development target of KALIMER has been set as to make KALIMER safer, more economic, more resistant to nuclear proliferation, and yield less impact on the environment. To achieve the target, study has been made for setting up the design concept of KALIMER including the assessment of various possible design alternatives. This report is the results of the study for the KALIMER concept study and describes the design concept of KALIMER. The developed design concept study and describes the design concept of KALIMER. The developed design concept is to be used as the starting point of the next development phase of conceptual design and the concept will be refined and modified in the conceptual design phase. The scope of the work has been set as the NSSS and essential BOP systems. For systems, NSSS and functionally related major BOP are covered. Sizing and specifying conceptual structure are covered for major equipment. Equipment and piping are arranged for the parts where the arrangement is critical in fulfilling the foresaid intention of setting up the KALIMER design concept. This report consists of 10 chapters. Chapter 2 is for the top level design requirements of KALIMER and it serves as the basis of KALIMER design concept development. Chapter 3 summarizes the KALIMER concept and describes the general design features. The remaining chapters are for specific systems. (author). 29 tabs., 37 figs.

KALIMER design concept report

International Nuclear Information System (INIS)

Park, Chang Kyu; Kim, Young Cheol; Kim, Young In; Kim, Young Gyun; Kim, Eui Kwang; Song, Hoon; Chung, Hyun Tai; Hwang, Woan; Nam, Cheol; Sim Yoon Sub; Kim, Yeon Sik; Wim Myung Whan; Min, Byung Tae; Yoo, Bong; Lee, Jae Han; Lee, Hyeong Yeon; Kim, Jong Bum; Koo, Gyeong Hoi; Ham, Chang Shik; Kwon, Kee Choon; Kim, Jung Taek; Park, Jae Chang; Lee, Jung Woon; Lee, Yong Hee; Kim, Chang Hwoi; Sim, Bong Shick; Hahn, Do Hee; Choi, Jong Hyeun; Kwon, Sang Woon.

1997-07-01

KAERI is working for the development of KALIMER and work is being done for methodology development, experimental facility set up and design concept development. The development target of KALIMER has been set as to make KALIMER safer, more economic, more resistant to nuclear proliferation, and yield less impact on the environment. To achieve the target, study has been made for setting up the design concept of KALIMER including the assessment of various possible design alternatives. This report is the results of the study for the KALIMER concept study and describes the design concept of KALIMER. The developed design concept study and describes the design concept of KALIMER. The developed design concept is to be used as the starting point of the next development phase of conceptual design and the concept will be refined and modified in the conceptual design phase. The scope of the work has been set as the NSSS and essential BOP systems. For systems, NSSS and functionally related major BOP are covered. Sizing and specifying conceptual structure are covered for major equipment. Equipment and piping are arranged for the parts where the arrangement is critical in fulfilling the foresaid intention of setting up the KALIMER design concept. This report consists of 10 chapters. Chapter 2 is for the top level design requirements of KALIMER and it serves as the basis of KALIMER design concept development. Chapter 3 summarizes the KALIMER concept and describes the general design features. The remaining chapters are for specific systems. (author). 29 tabs., 37 figs

Summary of classical general relativity workshop

Indian Academy of Sciences (India)

In the classical general relativity workshop, ten lectures were presented on various topics. The topics included aspects of black-hole physics, gravitational collapse and the formation of black holes, specific stellar models like a superdense star, method of extracting solutions by exploiting Noether symmetry, brane world and.

How unique is continuity of care? A review of continuity and related concepts.

Science.gov (United States)

Uijen, Annemarie A; Schers, Henk J; Schellevis, François G; van den Bosch, Wil J H M

2012-06-01

The concept of 'continuity of care' has changed over time and seems to be entangled with other care concepts, for example coordination and integration of care. These concepts may overlap, and differences between them often remain unclear. In order to clarify the confusion of tongues and to identify core values of these patient-centred concepts, we provide a historical overview of continuity of care and four related concepts: coordination of care, integration of care, patient-centred care and case management. We identified and reviewed articles including a definition of one of these concepts by performing an extensive literature search in PubMed. In addition, we checked the definition of these concepts in the Oxford English Dictionary. Definitions of continuity, coordination, integration, patient-centred care and case management vary over time. These concepts show both great entanglement and also demonstrate differences. Three major common themes could be identified within these concepts: personal relationship between patient and care provider, communication between providers and cooperation between providers. Most definitions of the concepts are formulated from the patient's perspective. The identified themes appear to be core elements of care to patients. Thus, it may be valuable to develop an instrument to measure these three common themes universally. In the patient-centred medical home, such an instrument might turn out to be an important quality measure, which will enable researchers and policy makers to compare care settings and practices and to evaluate new care interventions from the patient perspective.

General relativity with applications to astrophysics

CERN Document Server

Straumann, Norbert

2004-01-01

This text provides a comprehensive and timely introduction to general relativity The foundations of the theory in Part I are thoroughly developed together with the required mathematical background from differential geometry in Part III The six chapters in Part II are devoted to tests of general relativity and to many of its applications Binary pulsars are studied in considerable detail Much space is devoted to the study of compact objects, especially to black holes This includes a detailed derivation of the Kerr solution, Israel's proof of his uniqueness theorem, and derivations of the basic laws of black hole physics The final chapter of this part contains Witten's proof of the positive energy theorem The book addresses undergraduate and graduate students in physics, astrophysics and mathematics It is very well structured and should become a standard text for a modern treatment of gravitational physics The clear presentation of differential geometry makes it also useful for string theory and other fields of ...

DSR Theories, Conformal Group and Generalized Commutation Relation

International Nuclear Information System (INIS)

Leiva, Carlos

2006-01-01

In this paper the relationship of DSR theories and Conformal Group is reviewed. On the other hand, the relation between DSR Magueijo Smolin generators and generalized commutation relations is also shown

Quantum information and general relativity

Energy Technology Data Exchange (ETDEWEB)

Peres, A. [Technion, Israel Institute of Technology, Haifa (Israel)

2004-12-01

The Einstein-Podolsky-Rosen paradox (1935) is reexamined in the light of Shannon's information theory (1948). The EPR argument did not take into account that the observers' information was localized, like any other physical object. General relativity introduces new problems: there are horizons which act as on-way membranes for the propagation of quantum information, in particular black holes which act like sinks. (Abstract Copyright [2004], Wiley Periodicals, Inc.)

Introduction to general relativity, black holes and cosmology

CERN Document Server

Choquet-Bruhat, Yvonne

2015-01-01

General Relativity is a beautiful geometric theory, simple in its mathematical formulation but leading to numerous consequences with striking physical interpretations: gravitational waves, black holes, cosmological models, and so on. This introductory textbook is written for mathematics students interested in physics and physics students interested in exact mathematical formulations (or for anyone with a scientific mind who is curious to know more of the world we live in), recent remarkable experimental and observational results which confirm the theory are clearly described and no specialised physics knowledge is required. The mathematical level of Part A is aimed at undergraduate students and could be the basis for a course on General Relativity. Part B is more advanced, but still does not require sophisticated mathematics. Based on Yvonne Choquet-Bruhat's more advanced text, General Relativity and the Einstein Equations, the aim of this book is to give with precision, but as simply as possible, the found...

The hue of concepts.

Science.gov (United States)

Albertazzi, Liliana; Canal, Luisa; Malfatti, Michela; Micciolo, Rocco

2013-01-01

The study shows a systematic naturally biased association between percepts and concepts. Specifically, it shows that a series of terms pertaining to an abstract semantic field (related to the frame of ethics in social behaviour) has a nonrandom, highly significant, association with colours (hues). This is the first time that consistent associations between abstract terms and colours have been reported in the general population. The main hypothesis, ie that there appear to be 'hues of concepts', was borne out by the results: the abstract terms considered were coloured with blue/green (ie cool) colours as well as their synonyms, while their antonyms were coloured with red/yellow (ie warm) colours. The association provides information about the nature of abstract concepts and their relationship with perception. It also sheds light on the interrelations among words in semantic domains that, to date, have been studied from only a computational viewpoint.

The Viewpoints of Physics Teacher Candidates towards the Concepts in Special Theory of Relativity and Their Evaluation Designs

Science.gov (United States)

Turgut, Umit; Gurbuz, Fatih; Salar, Riza; Toman, Ufuk

2013-01-01

In this study, the viewpoints of physics teacher candidates at undergraduate level towards the concepts in special theory of relativity and the interpretations they made about these concepts were investigated. The viewpoints of the teacher candidates towards the concepts in the subject of special theory of relativity were revealed with six open…

Emergency planning, response and assessment: a concept for a center of excellence

International Nuclear Information System (INIS)

Dickerson, M.H.

1986-01-01

This paper discusses a general concept for a center of excellence devoted to emergency planning, response and assessment. A plan is presented to implement the concept, based on experience gained from emergency response as it relates to the nuclear and toxic chemical industries. The role of the World Laboratory in this endeavor would complement and enhance other organizations than are involved in related activities

Modern Canonical Quantum General Relativity;

International Nuclear Information System (INIS)

Kiefer, Claus

2008-01-01

The open problem of constructing a consistent and experimentally tested quantum theory of the gravitational field has its place at the heart of fundamental physics. The main approaches can be roughly divided into two classes: either one seeks a unified quantum framework of all interactions or one starts with a direct quantization of general relativity. In the first class, string theory (M-theory) is the only known example. In the second class, one can make an additional methodological distinction: while covariant approaches such as path-integral quantization use the four-dimensional metric as an essential ingredient of their formalism, canonical approaches start with a foliation of spacetime into spacelike hypersurfaces in order to arrive at a Hamiltonian formulation. The present book is devoted to one of the canonical approaches-loop quantum gravity. It is named modern canonical quantum general relativity by the author because it uses connections and holonomies as central variables, which are analogous to the variables used in Yang-Mills theories. In fact, the canonically conjugate variables are a holonomy of a connection and the flux of a non-Abelian electric field. This has to be contrasted with the older geometrodynamical approach in which the metric of three-dimensional space and the second fundamental form are the fundamental entities, an approach which is still actively being pursued. It is the author's ambition to present loop quantum gravity in a way in which every step is formulated in a mathematically rigorous form. The formal Leitmotiv of loop quantum gravity is background independence. Non-gravitational theories are usually quantized on a given non-dynamical background. In contrast, due to the geometrical nature of gravity, no such background exists in quantum gravity. Instead, the notion of a background is supposed to emerge a posteriori as an approximate notion from quantum states of geometry. As a consequence, the standard ultraviolet divergences of

Gravitational radiation and the validity of general relativity

International Nuclear Information System (INIS)

Will, C.M.

2001-01-01

The regular observation of gravitational radiation by a world-wide network of resonant and laser-interferometric detectors will usher in a new form of astronomy. At the same time, it will provide new and interesting tests of general relativity. We review the current empirical status of general relativity, and discuss three areas in which direct observation of gravitational radiation could test the theory further: polarization of the waves, speed of the waves, and back-reaction of the waves on the evolution of the source. (author)

Do New Production Concepts and a new Management of Employment Relations, yield higher Employee Performance and lower Job Strain?

Directory of Open Access Journals (Sweden)

Karolus Kraan

2007-05-01

Full Text Available In this article old versus new production concepts (NPCs and employment relation instruments, are studied, separately and in combination, to find out which yield high employee performance and low job strain. Therefore, in 2005, TNO conducted coupled surveys among 149 supervisors and employees. In the past decades, in reaction to dysfunctions of Tayloristic and professional bureaucratic production concepts and employment relations, several new forms of employment relations and NPCs, appeared. Examples are the Socio-technical NPC and customized employment relations. In this study both this NPC and customized employment relations - i.c. customized performance targets - demonstrate positive associations with employee performance. According to Socio-technical theory the design of employment relations is relatively unimportant, as human resources are mobilised primarily by the production concept. Our results for this NPC show the legitimacy of this assumption, because its high employee performance is irrespective of the employment relation instruments. On the contrary, in the other NPCs and in professional bureaucracies, the (employment relation instruments of respectively an increased period needed for learning the job, and customized performance targets can compensate for the lower employee performance in these production concepts. The results do not show increased job strain, due to new production concepts, or new employment relations. production concepts, employment relations, labour productivity, socio-technical theory

Specifying the Concept of Future Generations for Addressing Issues Related to High-Level Radioactive Waste.

Science.gov (United States)

Kermisch, Celine

2016-12-01

The nuclear community frequently refers to the concept of "future generations" when discussing the management of high-level radioactive waste. However, this notion is generally not defined. In this context, we have to assume a wide definition of the concept of future generations, conceived as people who will live after the contemporary people are dead. This definition embraces thus each generation following ours, without any restriction in time. The aim of this paper is to show that, in the debate about nuclear waste, this broad notion should be further specified and to clarify the related implications for nuclear waste management policies. Therefore, we provide an ethical analysis of different management strategies for high-level waste in the light of two principles, protection of future generations-based on safety and security-and respect for their choice. This analysis shows that high-level waste management options have different ethical impacts across future generations, depending on whether the memory of the waste and its location is lost, or not. We suggest taking this distinction into account by introducing the notions of "close future generations" and "remote future generations", which has important implications on nuclear waste management policies insofar as it stresses that a retrievable disposal has fewer benefits than usually assumed.

Generalized monotonicity from global minimization in fourth-order ODEs

NARCIS (Netherlands)

M.A. Peletier (Mark)

2000-01-01

textabstractWe consider solutions of the stationary Extended Fisher-Kolmogorov equation with general potential that are global minimizers of an associated variational problem. We present results that relate the global minimization property to a generalized concept of monotonicity of the solutions.

The general class of the vacuum spherically symmetric equations of the general relativity theory

International Nuclear Information System (INIS)

Karbanovski, V. V.; Sorokin, O. M.; Nesterova, M. I.; Bolotnyaya, V. A.; Markov, V. N.; Kairov, T. V.; Lyash, A. A.; Tarasyuk, O. R.

2012-01-01

The system of the spherical-symmetric vacuum equations of the General Relativity Theory is considered. The general solution to a problem representing two classes of line elements with arbitrary functions g 00 and g 22 is obtained. The properties of the found solutions are analyzed.

Spinor formalism and complex-vector formalism of general relativity

International Nuclear Information System (INIS)

Han-ying, G.; Yong-shi, W.; Gendao, L.

1974-01-01

In this paper, using E. Cartan's exterior calculus, we give the spinor form of the structure equations, which leads naturally to the Newman--Penrose equations. Furthermore, starting from the spinor spaces and the el (2C) algebra, we construct the general complex-vector formalism of general relativity. We find that both the Cahen--Debever--Defrise complex-vector formalism and that of Brans are its special cases. Thus, the spinor formalism and the complex-vector formalism of general relativity are unified on the basis of the uni-modular group SL(2C) and its Lie algebra

Some problems of special theory of relativity. (Concept of relativistic length)

International Nuclear Information System (INIS)

Strel'tsov, V.N.

1977-01-01

Two available definitions of the concept of length (distance) related (a) to moving the length standard and (b) to sending a light signal (similar to the radar method for measuring distances) are analyzed. Considerations in favour of the preferable use of the (b) definition are discussed. The extension of the (b) definition for fast moving bodies results in the introduction of the definition of relativistic length and volume. The increase of the longitudinal dimensions of fast moving objects is a consequence of the above definition. It should be noted that, e.g., for a rod, the definition corresponds to measurements on the lines orthogonal to the world strip of the given rod. It is shown that the known Michelson-Morley and Throuton-Noble experiments are naturally explained in the framework of the proposed concept of relativistic length. It is also shown that the definition introduced, unlike the conventional one, satisfies the principle of relativity

Age and Gender Differences in the Relation between Self-Concept Facets and Self-Esteem

Science.gov (United States)

Arens, A. Katrin; Hasselhorn, Marcus

2014-01-01

This study tested whether the gender intensification hypothesis applies to relations between multiple domain-specific self-concept facets and self-esteem. This hypothesis predicts gender-stereotypic differences in these relations and assumes they intensify with age. Furthermore, knowledge about gender-related or age-related differences in…

The KBS concepts - General outline, present study

International Nuclear Information System (INIS)

Pusch, R.

1980-01-01

The Swedish KBS 2 concept, which concerns spent, unreprocessed reactor fuel, implies the use of an 'engineered' barrier of highly compacted Na bentonite for isolating metal canisters with the wastes from the surrounding rock. The isolating power of a barrier of this kind will be so great that it will probably be suggested for other radioactive wastes as well

Generalized field-transforming metamaterials

International Nuclear Information System (INIS)

Tretyakov, Sergei A; Nefedov, Igor S; Alitalo, Pekka

2008-01-01

In this paper, we introduce a generalized concept of field-transforming metamaterials, which perform field transformations defined as linear relations between the original and transformed fields. These artificial media change the fields in a prescribed fashion in the volume occupied by the medium. We show what electromagnetic properties of transforming medium are required. The coefficients of these linear functions can be arbitrary scalar functions of position and frequency, which makes the approach quite general and opens a possibility to realize various unusual devices.

A comparison of Aboriginal and non-Aboriginal students on the inter-related dimensions of self-concept, strengths and achievement

Directory of Open Access Journals (Sweden)

Jessica Whitley

2014-10-01

Full Text Available Self-concept has been found to play a key role in academic and psychosocial outcomes for students. Appreciating the factors that have a bearing upon self-concept may be of particular importance for Aboriginal students, many of whom experience poorer outcomes than non-Aboriginal Canadians. The current study explored the relationships between multidimensional self-concept, perceived strengths and academic achievement among a sample Aboriginal and non-Aboriginal students. Results indicated that perceived self-concept and strengths were largely similar across groups. However, students in the two groups drew on different strengths to comprise their general self-concept. Findings are explored within the context of existing research and theory.

Indefinite-metric quantum field theory of general relativity

International Nuclear Information System (INIS)

Nakanishi, Noboru

1978-01-01

Quantum field theory of Einstein's general relativity is formulated in the indefinitemetric Hilbert space in such a way that asymptotic fields are manifestly Lorentz covariant and the physical S-matrix is unitary. The general coordinate transformation is transcribed into a q-number transformation, called the BRS transformation. Its abstract definition is presented on the basis of the BRS transformation for the Yang-Mills theory. The BRS transformation for general relativity is then explicitly constructed. The gauge-fixing Lagrangian density and the Faddeev-Popov one are introduced in such a way that their sum behaves like a scalar density under the BRS transformation. One can then proceed in the same way as in the Kugo-Ojima formalism of the Yang-Mills theory to establish the unitarity of the physical S-matrix. (author)

Supersymmetry, General Relativity and Unity of Nature

OpenAIRE

Shima, Kazunari; Tsuda, Motomu

2008-01-01

The basic idea and some physical implications of nonlinear supersymmetric general relativity (NLSUSY GR) are presented. NLSUSY GR may give new insights into the origin of mass and the mysterious relations between the cosmology and the low energy particle physics, e.g. the spontaneous SUSY breaking scale, the cosmological constant, the (dark) energy density of the universe and the neutrino mass.

Doppler frequency in interplanetary radar and general relativity

Science.gov (United States)

Mcvittie, G. C.

1972-01-01

The change of frequency of an interplanetary radar signal sent from the earth to another planet or to a space probe is worked out according to general relativity. The Schwarzschild spacetime is employed and its null geodesics control the motion of the signals. Exact Doppler frequency formulas are derived for one-way and two-way radar in terms of an arbitrary Schwarzschild radial coordinate. A reduction to the special relativity case is used to interpret the formulas in terms of the relative radial velocity of emitter and target. The general relativity corrections are worked out approximately for each of three possible Schwarzschild radial coordinates, and a numerical example is given. The amount of the correction is different according as one or the other of the Schwarzschild coordinates is identified with the radius vector deduced from classical celestial mechanics. The identification problem is discussed.

Activity-Based Restorative Therapies: Concepts and Applications in Spinal Cord Injury-Related Neurorehabilitation

Science.gov (United States)

Sadowsky, Cristina L.; McDonald, John W.

2009-01-01

Physical rehabilitation following spinal cord injury-related paralysis has traditionally focused on teaching compensatory techniques, thus enabling the individual to achieve day-to-day function despite significant neurological deficits. But the concept of an irreparable central nervous system (CNS) is slowly being replaced with evidence related to…

Kinematics in special and general relativity

International Nuclear Information System (INIS)

Woodside, R.W.M.

1979-05-01

This thesis investigates the problem of motion for extended bodies from the viewpoint of classical field theory, where the classical field is the body's energy-momentum or matter tensor. In special relativity a symmetric and divergence-free matter tensor combined with inertial frames is used to generate a kinematics for extended bodies. In general relativity the author suggests an analogous kinematics and applies it to the simplest non-trivial example of static, spherical stars, looking for special sets of vector fields whose matter currents are conserved. Such a set of ten vector fields defines a special frame, and integrals of the conserved matter currents define ten momenta whcih give the kinematics. Application of de Rham cohomology theory shows that the conserved matter currents for isolated bodies will have mechanical potentials which enable the momenta to be found from flux integrals evaluated in the vacuum region surrounding the body. These potentials contain the full Riemann curvature, allowing a body's general relativistic momenta to be determined by its vacuum graviational field

Diffeomorphism invariance in the Hamiltonian formulation of General Relativity

International Nuclear Information System (INIS)

Kiriushcheva, N.; Kuzmin, S.V.; Racknor, C.; Valluri, S.R.

2008-01-01

It is shown that when the Einstein-Hilbert Lagrangian is considered without any non-covariant modifications or change of variables, its Hamiltonian formulation leads to results consistent with principles of General Relativity. The first-class constraints of such a Hamiltonian formulation, with the metric tensor taken as a canonical variable, allow one to derive the generator of gauge transformations, which directly leads to diffeomorphism invariance. The given Hamiltonian formulation preserves general covariance of the transformations derivable from it. This characteristic should be used as the crucial consistency requirement that must be met by any Hamiltonian formulation of General Relativity

Implications of a positive cosmological constant for general relativity.

Science.gov (United States)

Ashtekar, Abhay

2017-10-01

Most of the literature on general relativity over the last century assumes that the cosmological constant [Formula: see text] is zero. However, by now independent observations have led to a consensus that the dynamics of the universe is best described by Einstein's equations with a small but positive [Formula: see text]. Interestingly, this requires a drastic revision of conceptual frameworks commonly used in general relativity, no matter how small [Formula: see text] is. We first explain why, and then summarize the current status of generalizations of these frameworks to include a positive [Formula: see text], focusing on gravitational waves.

Promoting Self-Concept, Social Skills, and Interpersonal Relations: The Tootling Intervention.

Science.gov (United States)

Wilson, Patti; Rhymer, Katrina; Landis, Julie; Skinner, Christopher

A project was undertaken to investigate the effects of tootling on social skills, self-concept, interpersonal relations, and classroom environment. The tootling intervention reinforces students for engaging in acts of kindness. Two fifth-grade classes participated in the study over a seven-week period. The Social Skills Rating System, the…

Moral distress: a comparative analysis of theoretical understandings and inter-related concepts.

Science.gov (United States)

Lützén, Kim; Kvist, Beatrice Ewalds

2012-03-01

Research on ethical dilemmas in health care has become increasingly salient during the last two decades resulting in confusion about the concept of moral distress. The aim of the present paper is to provide an overview and a comparative analysis of the theoretical understandings of moral distress and related concepts. The focus is on five concepts: moral distress, moral stress, stress of conscience, moral sensitivity and ethical climate. It is suggested that moral distress connects mainly to a psychological perspective; stress of conscience more to a theological-philosophical standpoint; and moral stress mostly to a physiological perspective. Further analysis indicates that these thoughts can be linked to the concepts of moral sensitivity and ethical climate through a relationship to moral agency. Moral agency comprises a moral awareness of moral problems and moral responsibility for others. It is suggested that moral distress may serve as a positive catalyst in exercising moral agency. An interdisciplinary approach in research and practice broadens our understanding of moral distress and its impact on health care personnel and patient care.

Generalized string theory mapping relations between gravity and gauge theory

International Nuclear Information System (INIS)

Bjerrum-Bohr, N.E.J.

2003-01-01

A previous study of the Kawai, Lewellen and Tye (KLT) relations between gravity and gauge theories, imposed by the relationship of closed and open strings, are here extended in the light of general relativity and Yang-Mills theory as effective field theories. We discuss the possibility of generalizing the traditional KLT mapping in this effective setting. A generalized mapping between the effective Lagrangians of gravity and Yang-Mills theory is presented, and the corresponding operator relations between gauge and gravity theories at the tree level are further explored. From this generalized mapping remarkable diagrammatic relations are found, linking diagrams in gravity and Yang-Mills theory, as well as diagrams in pure effective Yang-Mills theory. Also the possibility of a gravitational coupling to an antisymmetric field in the gravity scattering amplitude is considered, and shown to allow for mixed open-closed string solutions, i.e., closed heterotic strings

Noncommutative unification of general relativity and quantum mechanics

International Nuclear Information System (INIS)

Heller, Michael; Pysiak, Leszek; Sasin, Wieslaw

2005-01-01

We present a model unifying general relativity and quantum mechanics based on a noncommutative geometry. This geometry is developed in terms of a noncommutative algebra A which is defined on a transformation groupoid Γ given by the action of a noncompact group G on the total space E of a principal fiber bundle over space-time M. The case is important since to obtain physical effects predicted by the model we should assume that G is a Lorentz group or some of its representations. We show that the generalized Einstein equation of the model has the form of the eigenvalue equation for the generalized Ricci operator, and all relevant operators in the quantum sector of the model are random operators; we study their dynamics. We also show that the model correctly reproduces general relativity and the usual quantum mechanics. It is interesting that the latter is recovered by performing the measurement of any observable. In the act of such a measurement the model 'collapses' to the usual quantum mechanics

Change in emotional self-concept following socio-cognitive training relates to structural plasticity of the prefrontal cortex.

Science.gov (United States)

Lumma, Anna-Lena; Valk, Sofie L; Böckler, Anne; Vrtička, Pascal; Singer, Tania

2018-04-01

Self-referential processing is a key component of the emotional self-concept. Previous studies have shown that emotional self-referential processing is related to structure and function of cortical midline areas such as medial prefrontal cortex (mPFC), and that it can be altered on a behavioral level by specific mental training practices. However, it remains unknown how behavioral training-related change in emotional self-concept content relates to structural plasticity. To address this issue, we examined the relationship between training-induced change in participant's emotional self-concept measured through emotional word use in the Twenty Statement Test and change in cortical thickness in the context of a large-scale longitudinal mental training study called the ReSource Project . Based on prior behavioral findings showing increased emotional word use particularly after socio-cognitive training targeting perspective-taking capacities, this study extended these results by revealing that individual differences in the degree to which participants changed their emotional self-concept after training was positively related to cortical thickness change in right mPFC extending to dorsolateral PFC (dlPFC). Furthermore, increased self-related negative emotional word use after training was positively associated with cortical thickness change in left pars orbitalis and bilateral dlPFC. Our findings reveal training-related structural brain change in regions known to be involved in self-referential processing and cognitive control, and could indicate a relationship between restructuring of the emotional self-concept content as well as reappraisal of negative aspects and cortical thickness change. As such, our findings can guide the development of psychological interventions targeted to alter specific facets of the self-concept.

Determination of the Concepts "Profession" and "Role" in Relation to "Nurse Educator".

Science.gov (United States)

Pennbrant, Sandra

The aim of this study was to clarify the meanings and dimensions of the concepts "profession" and "role." The results from the concept determination were discussed in relation to the profession "nurse educator." This study is based on Koort's semantic analysis methods, using select parts of Eriksson's approach for concept determination, using dictionaries published between the years 1948 and 2015. The findings underline the complexity of the professional role of nurse educators. The nurse educator profession is based on society's trust and requires integration of ability, attitudes, norms, reflection, and theoretical knowledge, along with individual, organizational, and social conditions. Nurse educators must achieve a sufficient degree of pedagogical competence, subject competence, social competence and organizational competence in order to develop their professional role. When nurse educators define their function, a professional role takes form. Copyright © 2016 Elsevier Inc. All rights reserved.

Fractional Order Generalized Information

Directory of Open Access Journals (Sweden)

José Tenreiro Machado

2014-04-01

Full Text Available This paper formulates a novel expression for entropy inspired in the properties of Fractional Calculus. The characteristics of the generalized fractional entropy are tested both in standard probability distributions and real world data series. The results reveal that tuning the fractional order allow an high sensitivity to the signal evolution, which is useful in describing the dynamics of complex systems. The concepts are also extended to relative distances and tested with several sets of data, confirming the goodness of the generalization.

Introduction to some fundamental concepts of general relativity and to their required use in some modern timekeeping systems

Science.gov (United States)

Alley, C. O.

1982-01-01

Einstein's theory of gravity as curved space-time is presented. Emphasis is on the physical concepts, using only elementary mathematics. For the slow motions and weak gravitational fields experienced on Earth, the main curvature is that of time, not space. Experiments demonstrating this property are reviewed. The fundamental effects of motion and gravitational potential on clocks in many practical situations are discussed.

On stability relative to vector elements of the orbit in general relativity motion

International Nuclear Information System (INIS)

Abdil'din, M.M.; Bejsenova, N.A.

2002-01-01

In this work a question of a new type of stability - stability relative to vector elements of the orbit is considered in general relativity mechanics in case of the Lenze-Thirring and two body rotation. (author)

Generalized transformations and coordinates for static spherically symmetric general relativity

Science.gov (United States)

Hill, James M.; O'Leary, Joseph

2018-04-01

We examine a static, spherically symmetric solution of the empty space field equations of general relativity with a non-orthogonal line element which gives rise to an opportunity that does not occur in the standard derivations of the Schwarzschild solution. In these derivations, convenient coordinate transformations and dynamical assumptions inevitably lead to the Schwarzschild solution. By relaxing these conditions, a new solution possibility arises and the resulting formalism embraces the Schwarzschild solution as a special case. The new solution avoids the coordinate singularity associated with the Schwarzschild solution and is achieved by obtaining a more suitable coordinate chart. The solution embodies two arbitrary constants, one of which can be identified as the Newtonian gravitational potential using the weak field limit. The additional arbitrary constant gives rise to a situation that allows for generalizations of the Eddington-Finkelstein transformation and the Kruskal-Szekeres coordinates.

Generalized transformations and coordinates for static spherically symmetric general relativity.

Science.gov (United States)

Hill, James M; O'Leary, Joseph

2018-04-01

We examine a static, spherically symmetric solution of the empty space field equations of general relativity with a non-orthogonal line element which gives rise to an opportunity that does not occur in the standard derivations of the Schwarzschild solution. In these derivations, convenient coordinate transformations and dynamical assumptions inevitably lead to the Schwarzschild solution. By relaxing these conditions, a new solution possibility arises and the resulting formalism embraces the Schwarzschild solution as a special case. The new solution avoids the coordinate singularity associated with the Schwarzschild solution and is achieved by obtaining a more suitable coordinate chart. The solution embodies two arbitrary constants, one of which can be identified as the Newtonian gravitational potential using the weak field limit. The additional arbitrary constant gives rise to a situation that allows for generalizations of the Eddington-Finkelstein transformation and the Kruskal-Szekeres coordinates.

6th International Conference on the History of General Relativity

CERN Document Server

Eisenstaedt, Jean; The Universe of General Relativity; GR 6

2005-01-01

This volume from the Einstein Studies Series is based largely on papers presented at the Sixth International Conference on the History of General Relativity, held in Amsterdam on June 26-29, 2002. These contributions from notable experts offer both new and historical insights on gravitation, general relativity, cosmology, unified field theory, and the history of science. Topics discussed include the prehistory of special relativity, early attempts at a relativistic theory of gravitation, the beginnings of general relativity, the problem of motion in the context of relativity, conservation laws, the axiomatization of relativity, classical and contemporary cosmology, gravitation and electromagnetism, quantum gravity, and relativity as seen through the eyes of the public and renowned relativists. Contributors: K. Brading; G. Gale; H.F.M. Goenner; J. Goldberg; S. Katzir; D. Kennefick; H. Kragh; C. Lehner; U. Majer; J. Mattingly; E.T. Newman; J.D. Norton; J. Renn; R. Rynasiewicz; J.M. Sánchez-Ron; T. Sauer; C. Sm...

Concept theory

DEFF Research Database (Denmark)

Hjørland, Birger

2009-01-01

  Concept theory is an extremely broad, interdisciplinary and complex field of research related to many deep fields with very long historical traditions without much consensus. However, information science and knowledge organization cannot avoid relating to theories of concepts. Knowledge...... organizing systems (e.g. classification systems, thesauri and ontologies) should be understood as systems basically organizing concepts and their semantic relations. The same is the case with information retrieval systems. Different theories of concepts have different implications for how to construe......, evaluate and use such systems. Based on "a post-Kuhnian view" of paradigms this paper put forward arguments that the best understanding and classification of theories of concepts is to view and classify them in accordance with epistemological theories (empiricism, rationalism, historicism and pragmatism...

Generating perfect fluid spheres in general relativity

Science.gov (United States)

Boonserm, Petarpa; Visser, Matt; Weinfurtner, Silke

2005-06-01

Ever since Karl Schwarzschild’s 1916 discovery of the spacetime geometry describing the interior of a particular idealized general relativistic star—a static spherically symmetric blob of fluid with position-independent density—the general relativity community has continued to devote considerable time and energy to understanding the general-relativistic static perfect fluid sphere. Over the last 90 years a tangle of specific perfect fluid spheres has been discovered, with most of these specific examples seemingly independent from each other. To bring some order to this collection, in this article we develop several new transformation theorems that map perfect fluid spheres into perfect fluid spheres. These transformation theorems sometimes lead to unexpected connections between previously known perfect fluid spheres, sometimes lead to new previously unknown perfect fluid spheres, and in general can be used to develop a systematic way of classifying the set of all perfect fluid spheres.

Generating perfect fluid spheres in general relativity

International Nuclear Information System (INIS)

Boonserm, Petarpa; Visser, Matt; Weinfurtner, Silke

2005-01-01

Ever since Karl Schwarzschild's 1916 discovery of the spacetime geometry describing the interior of a particular idealized general relativistic star--a static spherically symmetric blob of fluid with position-independent density--the general relativity community has continued to devote considerable time and energy to understanding the general-relativistic static perfect fluid sphere. Over the last 90 years a tangle of specific perfect fluid spheres has been discovered, with most of these specific examples seemingly independent from each other. To bring some order to this collection, in this article we develop several new transformation theorems that map perfect fluid spheres into perfect fluid spheres. These transformation theorems sometimes lead to unexpected connections between previously known perfect fluid spheres, sometimes lead to new previously unknown perfect fluid spheres, and in general can be used to develop a systematic way of classifying the set of all perfect fluid spheres

Quantum theory and Einstein's general relativity

International Nuclear Information System (INIS)

Borzeszkowski, H. von; Treder, H.

1982-01-01

We dicusss the meaning and prove the accordance of general relativity, wave mechanics, and the quantization of Einstein's gravitation equations themselves. Firstly, we have the problem of the influence of gravitational fields on the de Broglie waves, which influence is in accordance with Einstein's weak principle of equivalence and the limitation of measurements given by Heisenberg's uncertainty relations. Secondly, the quantization of the gravitational fields is a ''quantization of geometry.'' However, classical and quantum gravitation have the same physical meaning according to limitations of measurements given by Einstein's strong principle of equivalence and the Heisenberg uncertainties for the mechanics of test bodies

On unifying concepts in plasticity theory and related matters in numerical analysis

International Nuclear Information System (INIS)

Havner, K.S.

1977-01-01

This paper reviews a rate-independent theory (or class of theories) of multiple-mode plastic straining which unifies various constitutive equations of macroscopic solids and single crystals. Some consideration is given to the relationship between the multiple-mode theory and thermodynamic concepts; including physical aspects of finite distortion of metal crystals. Uniqueness criteria and related minimum principles in incremental (or 'rate-type') boundary value problems are presented for the general class at finite strain. Special circumstances (one being infinitesimal strain) are defined under which the uniqueness criteria assure convergence of a form of finite element approximation in the boundary value problem. Extensive reference is made to recently published work of Hill, Rice, Sewell and Havner. A symmetry postulate pertaining to the 'effective hardening moduli' plays a key role in the general theory. This postulate permits the adoption of Sewell's multiple-mode saddle function as a potential for stress and plastic mechanism rates and leads to the connection between uniqueness and (rate-type) minimum principles. The postulate has a remarkable consequence for application of a simple form of the theory to single crystals in the tensile test. At small strain this theory reduces to the classical Taylor hardening of crystals, which has had wide application in micromechanical calculations of crystalline aggregate models. At infinitesimal strain, and at finite strain when the two dominant principal stresses are everywhere tensile, additional minimum principles are given for the 'self-straining problem' which permit the independent variation of displacement and plastic mechanism rates

A precise extragalactic test of General Relativity.

Science.gov (United States)

Collett, Thomas E; Oldham, Lindsay J; Smith, Russell J; Auger, Matthew W; Westfall, Kyle B; Bacon, David; Nichol, Robert C; Masters, Karen L; Koyama, Kazuya; van den Bosch, Remco

2018-06-22

Einstein's theory of gravity, General Relativity, has been precisely tested on Solar System scales, but the long-range nature of gravity is still poorly constrained. The nearby strong gravitational lens ESO 325-G004 provides a laboratory to probe the weak-field regime of gravity and measure the spatial curvature generated per unit mass, γ. By reconstructing the observed light profile of the lensed arcs and the observed spatially resolved stellar kinematics with a single self-consistent model, we conclude that γ = 0.97 ± 0.09 at 68% confidence. Our result is consistent with the prediction of 1 from General Relativity and provides a strong extragalactic constraint on the weak-field metric of gravity. Copyright © 2018 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.

Effects of Aging Stereotype Threat on Working Self-Concepts: An Event-Related Potentials Approach

Science.gov (United States)

Zhang, Baoshan; Lin, Yao; Gao, Qianyun; Zawisza, Magdalena; Kang, Qian; Chen, Xuhai

2017-01-01

Although the influence of stereotype threat (ST) on working self-concepts has been highlighted in recent years, its neural underpinnings are unclear. Notably, the aging ST, which largely influences older adults’ cognitive ability, mental and physical health, did not receive much attention. In order to investigate these issues, electroencephalogram (EEG) data were obtained from older adults during a modified Stroop task using neutral words, positive and negative self-concept words in aging ST vs. neutral control conditions. Results showed longer reaction times (RTs) for identifying colors of words under the aging ST compared to the neutral condition. More importantly, the negative self-concept elicited more positive late P300 amplitudes and enhanced theta band activities compared to the positive self-concept or neutral words under the aging ST condition, whereas no difference was found between these self-concepts and neutral words in the control condition. Furthermore, the aging ST induced smaller theta band synchronization and enhanced alpha band synchronization compared to the control condition. Moreover, we also observed valence differences in self-concepts where the negative self-concept words reduced early P150/N170 complex relative to neutral words. These findings suggest that priming ST could activate negative self-concepts as current working self-concept, and that this influence occurred during a late neural time course. PMID:28747885

Effects of Aging Stereotype Threat on Working Self-Concepts: An Event-Related Potentials Approach

Directory of Open Access Journals (Sweden)

Baoshan Zhang

2017-07-01

Full Text Available Although the influence of stereotype threat (ST on working self-concepts has been highlighted in recent years, its neural underpinnings are unclear. Notably, the aging ST, which largely influences older adults’ cognitive ability, mental and physical health, did not receive much attention. In order to investigate these issues, electroencephalogram (EEG data were obtained from older adults during a modified Stroop task using neutral words, positive and negative self-concept words in aging ST vs. neutral control conditions. Results showed longer reaction times (RTs for identifying colors of words under the aging ST compared to the neutral condition. More importantly, the negative self-concept elicited more positive late P300 amplitudes and enhanced theta band activities compared to the positive self-concept or neutral words under the aging ST condition, whereas no difference was found between these self-concepts and neutral words in the control condition. Furthermore, the aging ST induced smaller theta band synchronization and enhanced alpha band synchronization compared to the control condition. Moreover, we also observed valence differences in self-concepts where the negative self-concept words reduced early P150/N170 complex relative to neutral words. These findings suggest that priming ST could activate negative self-concepts as current working self-concept, and that this influence occurred during a late neural time course.

Simple recursion relations for general field theories

International Nuclear Information System (INIS)

Cheung, Clifford; Shen, Chia-Hsien; Trnka, Jaroslav

2015-01-01

On-shell methods offer an alternative definition of quantum field theory at tree-level, replacing Feynman diagrams with recursion relations and interaction vertices with a handful of seed scattering amplitudes. In this paper we determine the simplest recursion relations needed to construct a general four-dimensional quantum field theory of massless particles. For this purpose we define a covering space of recursion relations which naturally generalizes all existing constructions, including those of BCFW and Risager. The validity of each recursion relation hinges on the large momentum behavior of an n-point scattering amplitude under an m-line momentum shift, which we determine solely from dimensional analysis, Lorentz invariance, and locality. We show that all amplitudes in a renormalizable theory are 5-line constructible. Amplitudes are 3-line constructible if an external particle carries spin or if the scalars in the theory carry equal charge under a global or gauge symmetry. Remarkably, this implies the 3-line constructibility of all gauge theories with fermions and complex scalars in arbitrary representations, all supersymmetric theories, and the standard model. Moreover, all amplitudes in non-renormalizable theories without derivative interactions are constructible; with derivative interactions, a subset of amplitudes is constructible. We illustrate our results with examples from both renormalizable and non-renormalizable theories. Our study demonstrates both the power and limitations of recursion relations as a self-contained formulation of quantum field theory.

Factors relating to professional self-concept among nurse managers.

Science.gov (United States)

Kantek, Filiz; Şimşek, Belkıs

2017-12-01

To investigate the self-concept in nurse managers in Turkey and the effects of certain variables on professional self-concept. Professional self-concept plays a significant role in improving certain professional behaviours. Nursing managers have the potential to influence other members of the profession with their attitudes and behaviours. The study was designed as a cross-sectional descriptive study. This study was conducted with 159 nurse managers in nine different hospitals. The study data were collected with a Personal Information Form and Professional Self-concept Nursing Inventory, and the data analysis was accomplished with descriptive statistics, Cronbach's alpha coefficients and Chi-squared Automatic Interaction Detector analyses. The professional self-concept score of nurse managers was 3·33 (SD = 0·308). Professional competence subdimension had the highest scores, while professional satisfaction subdimension had the lowest. The types of hospital were found to be influential on professional self-concept. The types of hospital were reported to influence the professional self-concept of nurses. Nursing managers are visionaries who can potentially influence nursing practices and decisions. Nursing leaders must monitor and administer strategies to improve their professional self-concept. © 2017 John Wiley & Sons Ltd.

Generalization of Gibbs Entropy and Thermodynamic Relation

OpenAIRE

Park, Jun Chul

2010-01-01

In this paper, we extend Gibbs's approach of quasi-equilibrium thermodynamic processes, and calculate the microscopic expression of entropy for general non-equilibrium thermodynamic processes. Also, we analyze the formal structure of thermodynamic relation in non-equilibrium thermodynamic processes.

Prospective Mathematics Teachers' Ability to Identify Mistakes Related to Angle Concept of Sixth Grade Students

Science.gov (United States)

Arslan, Cigdem; Erbay, Hatice Nur; Guner, Pinar

2017-01-01

In the present study we try to highlight prospective mathematics teachers' ability to identify mistakes of sixth grade students related to angle concept. And also we examined prospective mathematics teachers' knowledge of angle concept. Study was carried out with 30 sixth-grade students and 38 prospective mathematics teachers. Sixth grade students…

Adolescent Girls' Self-Concept and Its Related Factors Based on Roy Adaptation Model

OpenAIRE

M. Basiri Moghadam; SH. Khosravan; L. Sadeghmoghadam; N. Ebrahimi Senoo

2017-01-01

Aims: One of the most important factors of individual health in the adolescents is the self-concept. As a nursing model, the Roy adaptation model mainly investigates the factor. The aim of the study was to investigate the self-concept and its related factors in the adolescent girls in Gonabad Township, based on the Roy adaptation model. Instrument & Methods: In the descriptive cross-sectional study, 270 adolescent girls were studied in Gonabad Township, Iran, in 2015. The subjects were s...

Value concepts and value based collaboration in building projects

DEFF Research Database (Denmark)

Jensen, Per Anker

2005-01-01

Value has in recent years become a popular term in management theory and practice in general as well as in economic theory and architectural management. This paper attempts to clarify the various uses and meanings of concepts of value/values. Six different value concepts are identified. The ori......-gin and use of value concepts in classic and modern economic theory and in management theory is outlined. The question of objectivity and subjectivity is discussed in relation to economic value and customer value. Value creation is put in relation to development in products and processes and a number...... of design strategies are identified. The concept and methods of value based management and collaboration is discussed in this context. The paper is mainly theoretical and based on work during a MBA study in 2002-04 as well as many years of experience as building client and facilities manager....

FROM PUBLIC RELATIONS TO THE NEW CONCEPTS OF COMMUNICATION: TERMINOLOGICAL PROBLEMS

Directory of Open Access Journals (Sweden)

María Isabel Míguez González

2013-11-01

Full Text Available The terms public relations, communication management, corporate communication, institutional communication, business communication and organizational communication coexist in the professional field of communication without clear conceptual limits. In order to clarify this situation from an academic point of view, we reviewed the contributions about these terms made by Spanish authors, based on the oldest notion of public relations. The analysis shows significant discrepancies between different authors, who can not clearly define the scope of these concepts and their relationship to each other.

Optical drift effects in general relativity

Science.gov (United States)

Korzyński, Mikołaj; Kopiński, Jarosław

2018-03-01

We consider the question of determining the optical drift effects in general relativity, i.e. the rate of change of the apparent position, redshift, Jacobi matrix, angular distance and luminosity distance of a distant object as registered by an observer in an arbitrary spacetime. We present a fully relativistic and covariant approach, in which the problem is reduced to a hierarchy of ODE's solved along the line of sight. The 4-velocities and 4-accelerations of the observer and the emitter and the geometry of the spacetime along the line of sight constitute the input data. We build on the standard relativistic geometric optics formalism and extend it to include the time derivatives of the observables. In the process we obtain two general, non-perturbative relations: the first one between the gravitational lensing, represented by the Jacobi matrix, and the apparent position drift, also called the cosmic parallax, and the second one between the apparent position drift and the redshift drift. The applications of the results include the theoretical study of the drift effects of cosmological origin (so-called real-time cosmology) in numerical or exact Universe models.

Loop space representation of quantum general relativity and the group of loops

International Nuclear Information System (INIS)

Gambini, R.

1991-01-01

The action of the constraints of quantum general relativity on a general state in the loop representation is coded in terms of loop derivatives. These differential operators are related to the infinitesimal generators of the group of loops and generalize the area derivative first considered by Mandelstam. A new sector of solutions of the physical states space of nonperturbative quantum general relativity is found. (orig.)

The generalized Balescu-Lenard collision operator: A unifying concept for tokamak transport

International Nuclear Information System (INIS)

Mynick, H.E.

1987-08-01

The generalization of the Balescu-Lenard collision operator to its fully electromagnetic counterpart in Kaufman's action-angle formalism is derived and its properties investigated. The general form may be specialized to any particular geometry where the unperturbed particle motion is integrable, and thus includes cylindrical plasmas, inhomogeneous slabs with nonuniform magnetic fields, tokamaks, and the particularly simple geometry of the standard operator as special cases. The general form points to the commonality between axisymmetric, turbulent, and ripple transport, and implies properties (e.g., intrinsic ambipolarity) which should be shared by them, under appropriate conditions. Along with a turbulent ''anomalous diffusion coefficient'' calculated for tokamaks in previous work, an ''anomalous pinch'' term of closely related structure and scaling is also implied by the generalized operator. 20 refs

Anholonomic Cauchy problem in general relativity

International Nuclear Information System (INIS)

Stachel, J.

1980-01-01

The Lie derivative approach to the Cauchy problem in general relativity is applied to the evolution along an arbitrary timelike vector field for the case where the dynamical degrees of freedom are chosen as the (generally anholonomic) metric of the hypersurface elements orthogonal to the vector field. Generalizations of the shear, rotation, and acceleration are given for a nonunit timelike vector field, and applied to the three-plus-one breakup of the Riemann tensor into components parallel and orthogonal to the vector field, resulting in the anholonomic Gauss--Codazzi equations. A similar breakup of the Einstein field equations results in the form of the constraint and evolution equations for the anholonomic case. The results are applied to the case of a space--time with a timelike Killing vector field (stationary field) to demonstrate their utility. Other possible applications, such as in the numerical integration of the field equations, are mentioned. Definitions are given of three-index shear, rotation, and acceleration tensors, and their use in a two-plus-two decomposition of the Riemann tensor and field equations is indicated

The Concept of Carrying Capacity in Tourism

Directory of Open Access Journals (Sweden)

Josef Zelenka

2014-05-01

Full Text Available Carrying capacity is often pragmatically, theoretically as well as purely intuitively considered as a concept in the context of tourism sustainability. The carrying capacity application has the greatest potential in protected areas, in frequently visited cultural and natural attractions, and in relation to sustaining of the lifestyle of the local community and tourism destination potential in general. Despite its importance, partial applications, determination of basic theoretical principles, and specifying connection to the other theoretical concepts in tourism (particularly destination life cycle, LAC concept, visitors management, there still is a rightful opinion of some authors suggesting that there is no consistent theory of tourism carrying capacity. This theory would be the base for sophisticated practical carrying capacity applications. This paper is therefore focused on introduction of the theoretical concept of carrying capacity, which can be discussed and possibly further elaborated.

Experimental tests of general relativity: recent progress and future directions

International Nuclear Information System (INIS)

Turyshev, S G

2009-01-01

Einstein's general theory of relativity is the standard theory of gravity, especially where the needs of astronomy, astrophysics, cosmology, and fundamental physics are concerned. As such, this theory is used for many practical purposes involving spacecraft navigation, geodesy, and time transfer. We review the foundations of general relativity, discuss recent progress in tests of relativistic gravity, and present motivations for the new generation of high-accuracy tests of new physics beyond general relativity. Space-based experiments in fundamental physics are presently capable of uniquely addressing important questions related to the fundamental laws of nature. We discuss the advances in our understanding of fundamental physics that are anticipated in the near future and evaluate the discovery potential of a number of recently proposed space-based gravitational experiments. (reviews of topical problems)

Introduction to general relativity

CERN Document Server

Parthasarthy, R

2016-01-01

INTRODUCTION TO GENERAL RELATIVITY begins with a description of the geometry of curved space, explaining geodesics, parallel transport, covariant differentiation, geodesic deviation and spacetime symmetry by killing vectors. It then introduces Einstein's theory of gravitation followed by Schwarzschild solution with its relevance to Positive Mass theorem. The three tests for Einstein's gravity are explained. Other exact solutions such as Vaidya, Kerr and Reisner - Nordstrom metric are included. In the Chapter on cosmological solutions, a detailed description of Godel metric is provided. It then introduces five dimensional spacetime of Kaluza showing the unification of gravity with electromagnetism. This is extended to include non-Abelian gauge theory by invoking compact extra dimensions. Explicit expressions in this case for Christoffel connections and ricci tensor are derived and the higher dimensional gravity action is shown to compactification are given.

Role Breadth Self-Efficacy and Foci of Proactive Behavior: Moderating Role of Collective, Relational, and Individual Self-Concept.

Science.gov (United States)

Hwang, Pin-Chyuan; Han, Ming-Chuan; Chiu, Su-Fen

2015-01-01

This study aims to identify the interactive effect of role breadth self-efficacy (RBSE) and the three levels of self-concept (collective, relational, and individual) in predicting of different foci of proactive behaviors. Results from 259 matched responses from an airline company in Taiwan showed that RBSE had a positive effect on (1) pro-organizational proactive behavior among those with higher collective self-concept, (2) pro-supervisor proactive behavior among those with higher relational self-concept, and (3) pro-self proactive behavior among those with higher individual self-concept. Our findings provide insights into the moderating role of different levels of self-concept on RBSE-proactive behavior process in terms of specific targets or beneficiaries. Further implications for organizational research and practice are discussed.

The diagnostic role of gut feelings in general practice A focus group study of the concept and its determinants

Directory of Open Access Journals (Sweden)

van der Weijden Trudy

2009-02-01

Full Text Available Abstract Background General practitioners sometimes base clinical decisions on gut feelings alone, even though there is little evidence of their diagnostic and prognostic value in daily practice. Research into these aspects and the use of the concept in medical education require a practical and valid description of gut feelings. The goal of our study was therefore to describe the concept of gut feelings in general practice and to identify their main determinants Methods Qualitative research including 4 focus group discussions. A heterogeneous sample of 28 GPs. Text analysis of the focus group discussions, using a grounded theory approach. Results Gut feelings are familiar to most GPs in the Netherlands and play a substantial role in their everyday routine. The participants distinguished two types of gut feelings, a sense of reassurance and a sense of alarm. In the former case, a GP is sure about prognosis and therapy, although they may not always have a clear diagnosis in mind. A sense of alarm means that a GP has the feeling that something is wrong even though objective arguments are lacking. GPs in the focus groups experienced gut feelings as a compass in situations of uncertainty and the majority of GPs trusted this guide. We identified the main determinants of gut feelings: fitting, alerting and interfering factors, sensation, contextual knowledge, medical education, experience and personality. Conclusion The role of gut feelings in general practice has become much clearer, but we need more research into the contributions of individual determinants and into the test properties of gut feelings to make the concept suitable for medical education.

Differential-associative processing or example elaboration: Which strategy is best for learning the definitions of related and unrelated concepts?

Science.gov (United States)

Hannon, Brenda

2012-10-01

Definitions of related concepts (e.g., genotype - phenotype ) are prevalent in introductory classes. Consequently, it is important that educators and students know which strategy(s) work best for learning them. This study showed that a new comparative elaboration strategy, called differential-associative processing, was better for learning definitions of related concepts than was an integrative elaborative strategy, called example elaboration. This outcome occurred even though example elaboration was administered in a naturalistic way (Experiment 1) and students spent more time in the example elaboration condition learning (Experiments 1, 2, 3), and generating pieces of information about the concepts (Experiments 2 and 3). Further, with unrelated concepts ( morpheme-fluid intelligence ), performance was similar regardless if students used differential-associative processing or example elaboration (Experiment 3). Taken as a whole, these results suggest that differential-associative processing is better than example elaboration for learning definitions of related concepts and is as good as example elaboration for learning definitions of unrelated concepts.

New ghost-free extensions of general relativity

International Nuclear Information System (INIS)

Mann, R.B.

1989-01-01

The method of algebraic extension is shown to yield a large class of gravitational theories which are extensions of general relativity. Requiring positivity of energy in the flat-space limit of such theories provides some constraints, but a large set of theories of potential phenomenological interest survives this condition. Explicit examples of such theories include the non-symmetric gravitational theory, algebraically extended Hilbert gravity and a one-parameter family of theories with dynamical torsion. In general such theories do not alter general relativistic post-Newtonian predictions for time delay experiments; rather they alter the non-linearities of the post-Newtonian gravitational potential. Such effects may be probed by measuring periastron shifts, as in the eclipsing binary systems Di Her and As Cam, as well as in the binary pulsar PSR 1913 + 16 (author)

Generalized Yosida Approximations Based on Relatively A-Maximal m-Relaxed Monotonicity Frameworks

Directory of Open Access Journals (Sweden)

Heng-you Lan

2013-01-01

Full Text Available We introduce and study a new notion of relatively A-maximal m-relaxed monotonicity framework and discuss some properties of a new class of generalized relatively resolvent operator associated with the relatively A-maximal m-relaxed monotone operator and the new generalized Yosida approximations based on relatively A-maximal m-relaxed monotonicity framework. Furthermore, we give some remarks to show that the theory of the new generalized relatively resolvent operator and Yosida approximations associated with relatively A-maximal m-relaxed monotone operators generalizes most of the existing notions on (relatively maximal monotone mappings in Hilbert as well as Banach space and can be applied to study variational inclusion problems and first-order evolution equations as well as evolution inclusions.

Cosmological perturbations in a family of deformations of general relativity

International Nuclear Information System (INIS)

Krasnov, Kirill; Shtanov, Yuri

2010-01-01

We study linear cosmological perturbations in a previously introduced family of deformations of general relativity characterized by the absence of new degrees of freedom. The homogeneous and isotropic background in this class of theories is unmodified and is described by the usual Friedmann equations. The theory of cosmological perturbations is modified and the relevant deformation parameter has the dimension of length. Gravitational perturbations of the scalar type can be described by a certain relativistic potential related to the matter perturbations just as in general relativity. A system of differential equations describing the evolution of this potential and of the stress-energy density perturbations is obtained. We find that the evolution of scalar perturbations proceeds with a modified effective time-dependent speed of sound, which, contrary to the case of general relativity, does not vanish even at the matter-dominated stage. In a broad range of values of the length parameter controlling the deformation, a specific transition from the regime of modified gravity to the regime of general relativity in the evolution of scalar perturbations takes place during the radiation domination. In this case, the resulting power spectrum of perturbations in radiation and dark matter is suppressed on the comoving spatial scales that enter the Hubble radius before this transition. We estimate the bounds on the deformation parameter for which this suppression does not lead to observable consequences. Evolution of scalar perturbations at the inflationary stage is modified but very slightly and the primordial spectrum generated during inflation is not noticeably different from the one obtained in general relativity

Implementation of the Multidimensional Modeling Concepts into Object-Relational Databases

Directory of Open Access Journals (Sweden)

2007-01-01

Full Text Available A key to survival in the business world is being able to analyze, plan and react to changing business conditions as fast as possible. With multidimensional models the managers can explore information at different levels of granularity and the decision makers at all levels can quickly respond to changes in the business climate-the ultimate goal of business intelligence. This paper focuses on the implementation of the multidimensional concepts into object-relational databases.

Matroidal Structure of Generalized Rough Sets Based on Tolerance Relations

Directory of Open Access Journals (Sweden)

Hui Li

2014-01-01

of the generalized rough set based on the tolerance relation. The matroid can also induce a new relation. We investigate the connection between the original tolerance relation and the induced relation.

Effects of Students' Pre- and Post-Laboratory Concept Maps on Students' Attitudes toward Chemistry Laboratory in University General Chemistry

Science.gov (United States)

Kilic, Ziya; Kaya, Osman Nafiz; Dogan, Alev

2004-01-01

The purpose of this study was to investigate the effects of scientific discussions based on student-constructed pre- and post-laboratory concept maps on students' attitudes toward chemistry laboratory in the university general chemistry. As part of instruction, during the first four laboratory sessions, students were taught how to construct and…

Between general relativity and quantum theory

International Nuclear Information System (INIS)

Rayski, J.

1982-01-01

Some possibilities of reconciling general relativity with quantum theory are discussed. The procedure of quantization is certainly not unique, but depends upon the choice of the coordinate conditions. Most versions of quantization predict the existence of gravitons, but it is also possible to formulate a quantum theory with a classical gravity whereby the expectation values of Tsub(μν) constitute the sources of the classical metric field. (author)

Generalized Habituation of Concept Stimuli in Toddlers

Science.gov (United States)

Faulkender, Patricia J.; And Others

1974-01-01

An evaluation of selective generalization of habituation on the basis of meaningful categories of stimuli. Also explored are the sex differences in conceptual generalization of habituation. Subjects were 36 toddlers with a mean age of 40 months. (SDH)

Self-concept and quality of object relations as predictors of outcome in short- and long-term psychotherapy.

Science.gov (United States)

Lindfors, Olavi; Knekt, Paul; Heinonen, Erkki; Virtala, Esa

2014-01-01

Quality of object relations and self-concept reflect clinically relevant aspects of personality functioning, but their prediction as suitability factors for psychotherapies of different lengths has not been compared. This study compared their prediction on psychiatric symptoms and work ability in short- and long-term psychotherapy. Altogether 326 patients, 20-46 years of age, with mood and/or anxiety disorder, were randomized to short-term (solution-focused or short-term psychodynamic) psychotherapy and long-term psychodynamic psychotherapy. The Quality of Object Relations Scale (QORS) and the Structural Analysis of Social Behavior (SASB) self-concept questionnaire were measured at baseline, and their prediction on outcome during the 3-year follow-up was assessed by the Symptom Check List Global Severity Index and the Anxiety Scale, the Beck Depression Inventory and by the Work Ability Index, Social Adjustment Scale work subscale and the Perceived Psychological Functioning scale. Negative self-concept strongly and self-controlling characteristics modestly predicted better 3-year outcomes in long-term therapy, after faster early gains in short-term therapy. Patients with a more positive or self-emancipating self-concept, or more mature object relations, experienced more extensive benefits after long-term psychotherapy. The importance of length vs. long-term therapy technique on the differences found is not known. Patients with mild to moderate personality pathology, indicated by poor self-concept, seem to benefit more from long-term than short-term psychotherapy, in reducing risk of depression. Long-term therapy may also be indicated for patients with relatively good psychological functioning. More research is needed on the relative importance of these characteristics in comparison with other patient-related factors. © 2013 Published by Elsevier B.V.

Main Features in the Concept of Digital Bildung

DEFF Research Database (Denmark)

Tække, Jesper; Paulsen, Michael

The question of this paper is how we can understand the concept of Bildung in the time of digital media seen from a Klafkian perspective. It draws on Klafki (2014) by extrapolating what he suggest is the main features of Bildung, answering six questions: how can education 1. Foster persons who can......, bringing about different levels of what we from a Klafkian perspective call Digital Bildung. (2) We relate the Klafkian concept of Bildung to an action research experiment called Socio Media Education (SME). In this research project we have worked together with teachers in an upper secondary school...... features of Bildung are then discussed in regard to digital media. We do this by relating the Klafkian concept of Bildung to (1) a general theory about how schools seem to respond to the new digital challenges and possibilities. Our main point is that these responses can be divided into three waves...

The concept of a bilingual dictionary

DEFF Research Database (Denmark)

Tarp, Sven

2005-01-01

The term bilingual dictionary is widely used, not only by librarians and dictionary users en general but also by professional lexicographers dedicated to the theory and practice of dictionary making. For this reason it should be expected that there were a common and well-established definition...... of the concept of a bilingual dictionary. It is evident that most people has an intuitive idea of what is meant by «bilingual dictionary». But science-based lexicographic theory - at least if it wants to be considered as such - must go beyond intuition and furnish precise definitions of the concepts used...... chapters, various definitions will be discussed and related to dictionary practice and, subsequently, the very concept of a bilingual dictionary will be examined in the light of a dictionary typology based upon the modern theory of lexicographic functions....

Relational Analysis of High School Students' Cognitive Self-Regulated Learning Strategies and Conceptions of Learning Biology

Science.gov (United States)

Sadi, Özlem

2017-01-01

The purpose of this study was to analyze the relation between students' cognitive learning strategies and conceptions of learning biology. The two scales, "Cognitive Learning Strategies" and "Conceptions of Learning Biology", were revised and adapted to biology in order to measure the students' learning strategies and…

The confrontation between general relativity and experiment

Indian Academy of Sciences (India)

... and tests of gravity at short distance to look for extra spatial dimensions could further constrain alternatives to general relativity. Laser Interferometric Gravitational Wave Observatories on Earth and in space may provide new tests of scalar–tensor gravity and graviton-mass theories via the properties of gravitational waves.

Einstein's General Theory of Relativity-with Modern Applications in Cosmology

International Nuclear Information System (INIS)

Barrabes, C

2008-01-01

The increasing prominence of general relativity in astrophysics and cosmology is reflected in the growing number of texts, particularly at the undergraduate level. A natural attitude before opening a new one is to ask i) what makes this different from those already published? And ii) does it follow the 'physics-first approach' as for instance the book by Hartle where the basic physical concepts are introduced first with as little formalism as possible, or does it follow the more traditional 'math-first approach' for which the mathematical formalism comes first and is then applied to phyics? As announced in the title, a distinctive feature of the book by Gron and Hervik is the space (almost half the book) devoted to cosmology and in particular to some of the most recent developments in this rapidly evolving field. It is also apparent that the authors have chosen, like the majority of current books on general relativity, the 'math-first approach'. The book is divided into six parts, each of them subdivided into chapters with part VI containing a few short technical appendices. The first part of the book briefly presents in chapter I the principles of relativity, Newtonian mechanics and the Newtonian theory of gravity. In chapter II, a short introduction to special relativity is given. It seems at first surprising that the four-dimensional structure of space-time is not more fully exploited so that the reader would gain familiarity early on with notions like 4-velocity, 4-momentum and the stress-energy tensor. This is in fact postponed to part II as an illustration of the mathematical formalism. The second part is devoted to those elements of differential geometry needed in this kind of course. The authors' presentation is somewhat similar to that of the books by Misner, Thorne and Wheeler and by Straumann (2nd edition). Vectors and forms are treated separately and the formalism of differential forms is introduced in detail. The various kinds of differentiation on

Nonlinear Supersymmetric General Relativity and Unity of Nature

OpenAIRE

Shima, Kazunari; Tsuda, Motomu

2008-01-01

The basic idea and some physical implications of nonlinear supersymmetric general relativity (NLSUSY GR) are discussed, which give new insights into the origin of mass and the mysterious relations between the cosmology and the low energy particle physics, e.g. the spontaneous SUSY breaking scale, the cosmological constant, the (dark) energy density of the universe and the neutrino mass.

Generalized Superconductivity. Generalized Levitation

International Nuclear Information System (INIS)

Ciobanu, B.; Agop, M.

2004-01-01

In the recent papers, the gravitational superconductivity is described. We introduce the concept of generalized superconductivity observing that any nongeodesic motion and, in particular, the motion in an electromagnetic field, can be transformed in a geodesic motion by a suitable choice of the connection. In the present paper, the gravitoelectromagnetic London equations have been obtained from the generalized Helmholtz vortex theorem using the generalized local equivalence principle. In this context, the gravitoelectromagnetic Meissner effect and, implicitly, the gravitoelectromagnetic levitation are given. (authors)

Interacting electromagnetic waves in general relativity

International Nuclear Information System (INIS)

Griffiths, J.B.

1976-01-01

The problem is considered of finding exact solutions of the Einstein-Maxwell equations which describe the physical situation of two colliding and subsequently interacting electromagnetic waves. The general theory of relativity predicts a nonlinear interaction between electromagnetic waves. The situation is described using an approximate geometrical method, and a new exact solution describing two interacting electromagnetic waves is given. This describes waves emitted from two sources mutually focusing each other on the opposite source. (author)

Testing General Relativity with Pulsar Timing

Directory of Open Access Journals (Sweden)

Stairs Ingrid H.

2003-01-01

Full Text Available Pulsars of very different types, including isolated objects and binaries (with short- and long-period orbits, and white-dwarf and neutron-star companions provide the means to test both the predictions of general relativity and the viability of alternate theories of gravity. This article presents an overview of pulsars, then discusses the current status of and future prospects for tests of equivalence-principle violations and strong-field gravitational experiments.

Implementation Of Law Number 11 Of 2012 Concerning Child Related Criminal Justice System Concept Restorative Justice

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Intan Karangan

2016-09-01

Full Text Available This study aims to determine how the application of the concept of restorative justice in accordance with Law No. 11 of 2012 on Child Criminal Justice system. This study uses normative namely a study that discusses the problem based on the literature and legislation relating to the matter to be investigated. Law No. 11 of 2012 on the Criminal Justice System Child has provided a new concept in the criminal justice system, especially those in the juvenile justice system. Related to the concept of Restorative Justice or restorative justice is a resolution processes involving perpetrators, victims, families, and other relevant parties in a criminal act, jointly seek solutions to the offense and its implications by emphasizing restoration and not retribution

IDENTIFICATION OF BASES FOR EVALUATION OF THE BUSINESS EXCELLENCE STATUS IN RELATION TO THE CSR CONCEPT

Directory of Open Access Journals (Sweden)

Miriam Jankalová

2017-06-01

Full Text Available The process of globalization has started the need to achieve the Business Excellence status. Emphasizing the responsibility of the company's behaviour towards society and the environment is confirmed by the adoption of the concept of corporate social responsibility (CSR. Based on theoretical background review, there is no single unified methodology for the evaluation of the Business Excellence status in relation to the CSR concept. The aim of this paper is to identify bases for the evaluation of Business Excellence status in relation to the CSR concept. The most important tasks include: to identify internal and external factors affecting Business Excellence status; to identify CSR areas for the needs of evaluation of the Business Excellence status. Primary sources included especially national and foreign scientific publications.

Black-hole spectroscopy: testing general relativity through gravitational-wave observations

Energy Technology Data Exchange (ETDEWEB)

Dreyer, Olaf [Perimeter Institute of Theoretical Physics, 35 King Street North, Waterloo, Ontario, N2J 2G9 (Canada); Kelly, Bernard [Center for Gravitational Wave Physics, Center for Gravitational Physics and Geometry and Department of Physics, 104 Davey Laboratory, University Park, PA 16802 (United States); Krishnan, Badri [Max Planck Institut fuer Gravitationsphysik, Am Muehlenberg 1, D-14476 Golm (Germany); Finn, Lee Samuel [Center for Gravitational Wave Physics, Center for Gravitational Physics and Geometry, Department of Physics and Department of Astronomy and Astrophysics, 104 Davey Laboratory, University Park, PA 16802 (United States); Garrison, David [University of Houston, Clear Lake, 2700 Bay Area Bvd, Room 3531-2, Houston, TX 77058 (United States); Lopez-Aleman, Ramon [Physical Sciences Department, University of Puerto Rico, Rio Piedras Campus, Rio Piedras, Puerto Rico 00931 (Puerto Rico)

2004-02-21

Assuming that general relativity is the correct theory of gravity in the strong-field limit, can gravitational-wave observations distinguish between black holes and other compact object sources? Alternatively, can gravitational-wave observations provide a test of one of the fundamental predictions of general relativity: the no-hair theorem? Here we describe a definitive test of the hypothesis that observations of damped, sinusoidal gravitational waves originate from a black hole or, alternatively, that nature respects the general relativistic no-hair theorem. For astrophysical black holes, which have a negligible charge-to-mass ratio, the black-hole quasi-normal mode spectrum is characterized entirely by the black-hole mass and angular momentum and is unique to black holes. In a different theory of gravity, or if the observed radiation arises from a different source (e.g., a neutron star, strange matter or boson star), the spectrum will be inconsistent with that predicted for general relativistic black holes. We give a statistical characterization of the consistency between the noisy observation and the theoretical predictions of general relativity and a demonstration, through simulation, of the effectiveness of the test for strong sources.

Black-hole spectroscopy: testing general relativity through gravitational-wave observations

International Nuclear Information System (INIS)

Dreyer, Olaf; Kelly, Bernard; Krishnan, Badri; Finn, Lee Samuel; Garrison, David; Lopez-Aleman, Ramon

2004-01-01

Assuming that general relativity is the correct theory of gravity in the strong-field limit, can gravitational-wave observations distinguish between black holes and other compact object sources? Alternatively, can gravitational-wave observations provide a test of one of the fundamental predictions of general relativity: the no-hair theorem? Here we describe a definitive test of the hypothesis that observations of damped, sinusoidal gravitational waves originate from a black hole or, alternatively, that nature respects the general relativistic no-hair theorem. For astrophysical black holes, which have a negligible charge-to-mass ratio, the black-hole quasi-normal mode spectrum is characterized entirely by the black-hole mass and angular momentum and is unique to black holes. In a different theory of gravity, or if the observed radiation arises from a different source (e.g., a neutron star, strange matter or boson star), the spectrum will be inconsistent with that predicted for general relativistic black holes. We give a statistical characterization of the consistency between the noisy observation and the theoretical predictions of general relativity and a demonstration, through simulation, of the effectiveness of the test for strong sources

General practitioners' and district nurses' conceptions of the encounter with obese patients in primary health care

Directory of Open Access Journals (Sweden)

Rasmussen Finn

2011-02-01

Full Text Available Abstract Background Primary health care specialists have a key role in the management of obesity. Through understanding how they conceive the encounter with patients with obesity, treatment may be improved. The aim of this study was thus to explore general practitioners' and district nurses' conceptions of encountering patients with obesity in primary health care. Method Data were collected through semi-structured interviews, and analysed using a phenomenographic approach. The participants were 10 general practitioners (6 women, 4 men and 10 district nurses (7 women, 3 men from 19 primary health care centres within a well-defined area of Sweden. Results Five descriptive categories were identified: Adequate primary health care, Promoting lifestyle change, Need for competency, Adherence to new habits and Understanding patient attitudes. All participants, independent of gender and profession, were represented in the descriptive categories. Some profession and gender differences were, however, found in the underlying conceptions. The general staff view was that obesity had to be prioritised. However, there was also the contradictory view that obesity is not a disease and therefore not the responsibility of primary health care. Despite this, staff conceived it as important that patients were met with respect and that individual solutions were provided which could be adhered to step-by-step by the patient. Patient attitudes, such as motivation to change, evasive behaviour, too much trust in care and lack of self-confidence, were, however, conceived as major barriers to a fruitful encounter. Conclusions Findings from this study indicate that there is a need for development and organisation of weight management in primary health care. Raising awareness of staff's negative views of patient attitudes is important since it is likely that it affects the patient-staff relationship and staff's treatment efforts. More research is also needed on gender and

Conceptions of Parents, Conceptions of Self, and Conceptions of God.

Science.gov (United States)

Buri, John R.; Mueller, Rebecca A.

Different theorists have suggested that an individual's view of God may be related to one's view of one's father, one's mother, or one's self. A study was conducted to examine the relationship of college students' conceptions of the wrathfulness-kindliness of God to their conceptions of their father's and mother's permissiveness, authoritarianism,…

The generalized Crewther relation in QCD and its experimental consequences

International Nuclear Information System (INIS)

Brodsky, S.J.; Gabadadze, G.T.; Kataev, A.L.; Lu, H.J.

1995-12-01

We use the BLM scale-fixing prescription to derive a renormalization-scheme invariant relation between the coefficient function for the Bjorken sum rule for polarized deep inelastic scattering and the R-ratio for the e + e - annihilation cross section. This relation provides a generalization of the Crewther relation to non-conformally invariant gauge theories. The derived relations allow one to calculate unambiguously without renormalization scale or scheme ambiguity the effective charges of the polarized Bjorken and the Gross-Llewellen Smith sum rules from the experimental value for the effective charge associated with R-ratio. Present data are consistent with the generalized Crewther relations, but measurements at higher precision and energies will be needed to decisively test these fundamental relations in QCD. (orig.)

Tilted Bianchi type I dust fluid cosmological model in general relativity

Indian Academy of Sciences (India)

Tilted Bianchi type I dust fluid cosmological model in general relativity ... In this paper, we have investigated a tilted Bianchi type I cosmological model filled with dust of perfect fluid in general relativity. ... Pramana – Journal of Physics | News ...

Self-concept of children with cerebral palsy measured using the population-specific myTREEHOUSE Self-Concept Assessment.

Science.gov (United States)

Cheong, Sau Kuan; Lang, Cathryne P; Johnston, Leanne M

2018-02-01

Self-concept is an individual's perception of him/herself. Research into the self-concept of children with cerebral palsy (CP) has been sparse due to the lack of a population-specific self-concept instrument. Using the new myTREEHOUSE Self-Concept Assessment, this study investigated the self-concept of children with CP in relation to age, gender, motor, communication and cognitive function. Children with CP aged 8-12 years (n = 50; 29 males; mean 10 years 2 months; GMFCS-E&R I = 36, II = 8, III = 5, IV = 1) completed myTREEHOUSE and a standardised intelligence measure. Most children reported positive self-concept from all three myTREEHOUSE Performance Perspectives and over half (60%) fell within the Low range for the Personal Concern Score. Self-concept was not associated with age, gender, motor function, or communication function. However, for cognitive function, associations were observed for Social Skills (Below Average > Average cognitive function; Cohen's d = 1.07) and Learning Skills (Above Average > Average cognitive function; Cohen's d = 0.95) domains when rated from a Personal Performance Perspective. As the first study of the self-concept of children with CP using a CP-specific assessment, this study offers important insights into what children with CP think about themselves. Generally, the self-concept of children with CP was sound. Future research on environmental facilitators and barriers to robust self-concept development is recommended. Copyright © 2017 Elsevier Ltd. All rights reserved.

Gravitational redshift of galaxies in clusters as predicted by general relativity.

Science.gov (United States)

Wojtak, Radosław; Hansen, Steen H; Hjorth, Jens

2011-09-28

The theoretical framework of cosmology is mainly defined by gravity, of which general relativity is the current model. Recent tests of general relativity within the Lambda Cold Dark Matter (ΛCDM) model have found a concordance between predictions and the observations of the growth rate and clustering of the cosmic web. General relativity has not hitherto been tested on cosmological scales independently of the assumptions of the ΛCDM model. Here we report an observation of the gravitational redshift of light coming from galaxies in clusters at the 99 per cent confidence level, based on archival data. Our measurement agrees with the predictions of general relativity and its modification created to explain cosmic acceleration without the need for dark energy (the f(R) theory), but is inconsistent with alternative models designed to avoid the presence of dark matter. © 2011 Macmillan Publishers Limited. All rights reserved

Metaphors of Primary School Students Relating to the Concept of Global Warming

Science.gov (United States)

Dogru, Mustafa; Sarac, Esra

2013-01-01

The purpose of this study is to reveal the metaphors of primary school students (n = 362) relating to the concept of global warming. Data collected by completing the expression of "global warming is like..., because..." of the students were analysed by use of qualitative and quantitative data analysis techniques. According to findings of…

Factors Related to Students' Learning of Biomechanics Concepts

Science.gov (United States)

Hsieh, ChengTu; Smith, Jeremy D.; Bohne, Michael; Knudson, Duane

2012-01-01

The purpose of this study was to replicate and expand a previous study to identify the factors that affect students' learning of biomechanical concepts. Students were recruited from three universities (N = 149) located in the central and western regions of the United States. Data from 142 students completing the Biomechanics Concept Inventory…

Science-based occupations and the science curriculum: Concepts of evidence

Science.gov (United States)

Aikenhead, Glen S.

2005-03-01

What science-related knowledge is actually used by nurses in their day-to-day clinical reasoning when attending patients? The study investigated the knowledge-in-use of six acute-care nurses in a hospital surgical unit. It was found that the nurses mainly drew upon their professional knowledge of nursing and upon their procedural understanding that included a common core of concepts of evidence (concepts implicitly applied to the evaluation of data and the evaluation of evidence - the focus of this research). This core included validity triangulation, normalcy range, accuracy, and a general predilection for direct sensual access to a phenomenon over indirect machine-managed access. A cluster of emotion-related concepts of evidence (e.g. cultural sensitivity) was also discovered. These results add to a compendium of concepts of evidence published in the literature. Only a small proportion of nurses (one of the six nurses in the study) used canonical science content in their clinical reasoning, a result consistent with other research. This study also confirms earlier research on employees in science-rich workplaces in general, and on professional development programs for nurses specifically: canonical science content found in a typical science curriculum (e.g. high school physics) does not appear relevant to many nurses' knowledge-in-use. These findings support a curriculum policy that gives emphasis to students learning how to learn science content as required by an authentic everyday or workplace context, and to students learning concepts of evidence.

Generalized Weierstrass Relations and Frobenius Reciprocity

International Nuclear Information System (INIS)

Matsutani, Shigeki

2006-01-01

This article investigates local properties of the further generalized Weierstrass relations for a spin manifold S immersed in a higher dimensional spin manifold M from the viewpoint of the study of submanifold quantum mechanics. We show that the kernel of a certain Dirac operator defined over S, which we call a submanifold Dirac operator, gives the data of the immersion. In the derivation, the simple Frobenius reciprocity of Clifford algebras S and M plays an important role

Status of spent fuel dry storage concepts: concerns, issues and developments

International Nuclear Information System (INIS)

1985-11-01

This report is intended to provide the reader with a general understanding of the various dry storage concepts and facilities required to support them. The outstanding technical concerns relative to dry storage installations, as well as, past and planned demonstration programs are briefly described. Such other activities as the development and approval of a design criteria standard is presented. An updated review of the cost of the various concepts are discussed

Generalized concept for the estimation of body dose for radiation workers exposed to external #betta#-rays

International Nuclear Information System (INIS)

Piesch, E.; Boehm, J.; Heinzelmann, M.

1983-01-01

In radiation protection monitoring the need exists for an estimation of body dose due to external #betta#-rays, for instance if the #betta#-dose rate at the working area is expected to be high according to the data of source activity or room contamination, the indicated dose values of a personal dosemeter exceed the operational limit for the organ or tissue depth of interest, or a person was exposed to a significant dose. On behalf of the Federal Ministry of the Interior, Federal Republic of Germany, a guideline is now under preparation which offers a standardized concept of the estimation of #betta#-doses in personnel monitoring. The calculation models discussed here will be used as a basis for any case of external #betta#-irradiation where, in connection with the German Radiation Protection Ordinance, the ICRP dose equivalent limits are reached or the dosemeter readings are not representative for an individual exposure. The generalized concept discussed in the paper relates to: the calculation of #betta#-dose on the basis of source activity or spectral particle fluence and takes into account the special cases of point sources, area sources and volume sources; the estimation of body dose on the basis of calculated data or measured results from area or personnel monitoring, taking into account the dose equivalent in different depths of tissue, in particular the dose equivalent to the skin, the lens of the eye and other organs; and finally the estimation of skin dose due to the contamination of the skin surface. Basic reference data are presented in order to estimate the dose equivalent of interest which varies significantly in the #betta#-radiation field as a function of the maximum #betta#-energy, distance to the source, size of the source, activity per area for surface contamination and activity per volume for air contamination

Relations of Change in Condition Severity and School Self-Concept To Change in Achievement-Related Behavior in Children with Asthma or Epilepsy.

Science.gov (United States)

Huberty, Thomas J.; Austin, Joan K.; Huster, Gertrude A.; Dunn, David W.

2000-01-01

Explores relation of gender, change in condition of severity, and change in school self-concept, to change in teachers' ratings of academic-related behaviors in children with asthma or epilepsy. Tests showed that these children were near population mean in academic-related behaviors, except students with high-severity epilepsy. (Author/JDM)

Development and Assessment of a Diagnostic Tool to Identify Organic Chemistry Students' Alternative Conceptions Related to Acid Strength

Science.gov (United States)

McClary, LaKeisha M.; Bretz, Stacey Lowery

2012-01-01

The central goal of this study was to create a new diagnostic tool to identify organic chemistry students' alternative conceptions related to acid strength. Twenty years of research on secondary and college students' conceptions about acids and bases has shown that these important concepts are difficult for students to apply to qualitative problem…

A century of general relativity: astrophysics and cosmology.

Science.gov (United States)

Blandford, R D

2015-03-06

One hundred years after its birth, general relativity has become a highly successful physical theory in the sense that it has passed a large number of experimental and observational tests and finds extensive application to a wide variety of cosmic phenomena. It remains an active area of research as new tests are on the way, epitomized by the exciting prospect of detecting gravitational waves from merging black holes. General relativity is the essential foundation of the standard model of cosmology and underlies our description of the black holes and neutron stars that are ultimately responsible for the most powerful and dramatic cosmic sources. Its interface with physics on the smallest and largest scales will continue to provide fertile areas of investigation in its next century. Copyright © 2015, American Association for the Advancement of Science.

The motion of a charged particle in general relativity

International Nuclear Information System (INIS)

Ludvigsen, M.

1979-01-01

A new approach to the problem of the motion of a self-interacting massive charged particle in general relativity is presented. A charged Robinson-Trautman solution is used as a general relativistic model of such a particle. Such a solution is shown to generate a unique world line in its own H space, which is interpreted as the world line of the particle. Using the R-T dynamical relations, the equation of motion of the particle is derived, which, in the limiting case of zero curvature, is shown to be the same as the classical Lorentz-Dirac equation of motion. (author)

Essays in general relativity a Festschrift for Abraham Taub

CERN Document Server

Tipler, Frank J

1981-01-01

Essays in General Relativity: A Festschrift for Abraham Taub is collection of essays to honor Professor Abraham H. Taub on the occasion of his retirement from the mathematics faculty of the University of California at Berkeley. Relativistic hydrodynamics has always been a subject dear to Taub's heart. In fact, many basic results on special relativistic fluid flows are due to him, and he has been a major contributor to the study of fluid flows near shocks. The book contains 16 chapters and begins with a discussion of a geometrical approach to general relativity. This is followed by separate cha

Reformulation of the symmetries of first-order general relativity

Science.gov (United States)

Montesinos, Merced; González, Diego; Celada, Mariano; Díaz, Bogar

2017-10-01

We report a new internal gauge symmetry of the n-dimensional Palatini action with cosmological term (n>3 ) that is the generalization of three-dimensional local translations. This symmetry is obtained through the direct application of the converse of Noether’s second theorem on the theory under consideration. We show that diffeomorphisms can be expressed as linear combinations of it and local Lorentz transformations with field-dependent parameters up to terms involving the variational derivatives of the action. As a result, the new internal symmetry together with local Lorentz transformations can be adopted as the fundamental gauge symmetries of general relativity. Although their gauge algebra is open in general, it allows us to recover, without resorting to the equations of motion, the very well-known Lie algebra satisfied by translations and Lorentz transformations in three dimensions. We also report the analog of the new gauge symmetry for the Holst action with cosmological term, finding that it explicitly depends on the Immirzi parameter. The same result concerning its relation to diffeomorphisms and the open character of the gauge algebra also hold in this case. Finally, we consider the non-minimal coupling of a scalar field to gravity in n dimensions and establish that the new gauge symmetry is affected by this matter field. Our results indicate that general relativity in dimension greater than three can be thought of as a gauge theory.

Fundamental concepts and relations for reliability analysis of multi-state systems

International Nuclear Information System (INIS)

Murchland, J.D.

1975-01-01

The fundamental concepts and relations that should be used in the reliability analysis of systems with numerous components are discussed, with an emphasis on calculable quantities. These are: (1) the average probability of being in a state, (2) the average transition rates between states, in the long run or as time functions, and (3) the integrals of the transition rates, which are the expected numbers of transitions. These quantities are related by the net transition relations, and the calculationally vital transition rate relation when the inputs of an item are statistically independent. Assumptions necessary for the existence of these quantities and for the relations are listed, and proofs given. The importance of exploiting the closeness to ''simple'' structure which systems may possess, and the versatility for different problems of a computational technique of ''reduction'' and ''expansion'' are discussed. The key relations for the latter are formally derived. Applications are made to fault trees, structure networks, undirected and directed communication networks

Extension of Loop Quantum Gravity to Metric Theories beyond General Relativity

International Nuclear Information System (INIS)

Ma Yongge

2012-01-01

The successful background-independent quantization of Loop Quantum Gravity relies on the key observation that classical General Relativity can be cast into the connection-dynamical formalism with the structure group of SU(2). Due to this particular formalism, Loop Quantum Gravity was generally considered as a quantization scheme that applies only to General Relativity. However, we will show that the nonperturbative quantization procedure of Loop Quantum Gravity can be extended to a rather general class of metric theories of gravity, which have received increased attention recently due to motivations coming form cosmology and astrophysics. In particular, we will first introduce how to reformulate the 4-dimensional metric f(R) theories of gravity, as well as Brans-Dicke theory, into connection-dynamical formalism with real SU(2) connections as configuration variables. Through these formalisms, we then outline the nonpertubative canonical quantization of the f(R) theories and Brans-Dicke theory by extending the loop quantization scheme of General Relativity.

New developments and concepts related to biomarker application to vaccines

Science.gov (United States)

Ahmed, S. Sohail; Black, Steve; Ulmer, Jeffrey

2012-01-01

Summary This minireview will provide a perspective on new developments and concepts related to biomarker applications for vaccines. In the context of preventive vaccines, biomarkers have the potential to predict adverse events in select subjects due to differences in genetic make‐up/underlying medical conditions or to predict effectiveness (good versus poor response). When expanding them to therapeutic vaccines, their utility in identification of patients most likely to respond favourably (or avoid potentially negative effects of treatment) becomes self‐explanatory. Despite the progress made so far on dissection of various pathways of biological significance in humans, there is still plenty to unravel about the mysteries related to the quantitative and qualitative aspects of the human host response. This review will provide a focused overview of new concepts and developments in the field of vaccine biomarkers including (i) vaccine‐dependent signatures predicting subject response and safety, (ii) predicting therapeutic vaccine efficacy in chronic diseases, (iii) exploring the genetic make‐up of the host that may modulate subject‐specific adverse events or affect the quality of immune responses, and (iv) the topic of volunteer stratification as a result of biomarker screening (e.g. for therapeutic vaccines but also potentially for preventive vaccines) or as a reflection of an effort to compare select groups (e.g. vaccinated subjects versus patients recovering from infection) to enable the discovery of clinically relevant biomarkers for preventive vaccines. PMID:21895991

Numerical Hydrodynamics and Magnetohydrodynamics in General Relativity

Directory of Open Access Journals (Sweden)

Font José A.

2008-09-01

Full Text Available This article presents a comprehensive overview of numerical hydrodynamics and magnetohydrodynamics (MHD in general relativity. Some significant additions have been incorporated with respect to the previous two versions of this review (2000, 2003, most notably the coverage of general-relativistic MHD, a field in which remarkable activity and progress has occurred in the last few years. Correspondingly, the discussion of astrophysical simulations in general-relativistic hydrodynamics is enlarged to account for recent relevant advances, while those dealing with general-relativistic MHD are amply covered in this review for the first time. The basic outline of this article is nevertheless similar to its earlier versions, save for the addition of MHD-related issues throughout. Hence, different formulations of both the hydrodynamics and MHD equations are presented, with special mention of conservative and hyperbolic formulations well adapted to advanced numerical methods. A large sample of numerical approaches for solving such hyperbolic systems of equations is discussed, paying particular attention to solution procedures based on schemes exploiting the characteristic structure of the equations through linearized Riemann solvers. As previously stated, a comprehensive summary of astrophysical simulations in strong gravitational fields is also presented. These are detailed in three basic sections, namely gravitational collapse, black-hole accretion, and neutron-star evolutions; despite the boundaries, these sections may (and in fact do overlap throughout the discussion. The material contained in these sections highlights the numerical challenges of various representative simulations. It also follows, to some extent, the chronological development of the field, concerning advances in the formulation of the gravitational field, hydrodynamics and MHD equations and the numerical methodology designed to solve them. To keep the length of this article reasonable

The Motivational Effects of Types of Computer Feedback on Children's Learning and Retention of Relational Concepts.

Science.gov (United States)

Armour-Thomas, Eleanor; And Others

The effects of different types of feedback in computer assisted instruction (CAI) on relational concept learning by young children were compared in this study. Subjects were 89 kindergarten students whose primary language was English, and whose performance on the Boehm Test of Basic Concepts was within the average range chosen from classes in a…

Investigating Undergraduate Students’ Conceptions of Radiation

Science.gov (United States)

Romine, James M.; Buxner, Sanlyn; Impey, Chris; Nieberding, Megan; Antonellis, Jessie C.

2014-11-01

Radiation is an essential topic to the physical sciences yet is often misunderstood by the general public. The last time most people have formal instruction about radiation is as students in high school and this knowledge will be carried into adulthood. Peoples’ conceptions of radiation influence their attitude towards research regarding radiation, radioactivity, and other work where radiation is prevalent. In order to understand students’ ideas about radiation after having left high school, we collected science surveys from nearly 12,000 undergraduates enrolled in introductory science courses over a span of 25 years. This research investigates the relationship between students’ conceptions of radiation and students’ personal beliefs and academic field of study.Our results show that many students in the sample were unable to adequately describe radiation. Responses were typically vague, brief, and emotionally driven. Students’ field of study was found to significantly correlate with their conceptions. Students pursuing STEM majors were 60% more likely to describe radiation as an emission and/or form of energy and cited atomic or radioactive sources of radiation twice as often as non-STEM students. Additionally, students’ personal beliefs also appear to relate to their conceptions of radiation. The most prominent misconception shown was that radiation is a generically harmful substance, which was found to be consistent throughout the duration of the study. In particular, non-science majors in our sample had higher rates of misconceptions, often generalized the idea of radiation into a broad singular topic, and had difficulty properly identifying sources.Generalized ideas of radiation and the inability to properly recognize sources of radiation may contribute to the prevalent misconception that radiation is an inexplicably dangerous substance. A basic understanding of both electromagnetic and particulate radiation and the existence of radiation at various

Supervisors' approaches to supervision and how these relate to conceptions of research

DEFF Research Database (Denmark)

Kobayashi, Sofie; Grout, Brian William Wilson; Rump, Camilla Østerberg

how supervision is different or similar to research. Møller Madsen and Winsløw (2009) have investigated researchers' understanding of relations between research and teaching in two disciplines: Mathematics and Physical Geography using Chevallard's anthropological theory of didactics (Chevallard 2006...... are short of empirical studies that can shed light on the relations between supervisors' conceptions of research and their approaches to supervision. This work which lies in the research-teaching nexus arena of doctoral supervision has the potential to provide new insights into supervision by identifying...

Who am I? The relationship between self-concept uncertainty and materialism.

Science.gov (United States)

Noguti, Valeria; Bokeyar, Alexandra L

2014-10-01

It is well accepted that materialism may result in a number of negative consequences, hence the importance of improving its understanding. In this paper, we propose that materialism negatively relates to self-concept uncertainty. Uncertainty about oneself is aversive and those feeling uncertain may use the possession of material objects as a way to reduce the uncertainty. Inasmuch as material objects can serve as concrete signs of self-worth, self-concept uncertainty can therefore relate to more materialism. Over two studies, one in Australia and the other in the US, with a total of 390 participants, our research demonstrates that lower clarity about one's self-concept associates with higher levels of materialism. While this result holds for both genders, this relationship is considerably stronger for women compared to men. We also find that lower self-concept clarity relates to higher compulsive buying. We further demonstrate that materialism relates to higher positive moods during shopping, and also relates to higher negative moods after shopping, more notably negative moods towards what was purchased. This effect is significant even when controlling for general affective states. © 2014 International Union of Psychological Science.

Concepts and Relations in Neurally Inspired In Situ Concept-Based Computing

NARCIS (Netherlands)

van der Velde, Frank; van der Velde, Frank

2016-01-01

In situ concept-based computing is based on the notion that conceptual representations in the human brain are “in situ.” In this way, they are grounded in perception and action. Examples are neuronal assemblies, whose connection structures develop over time and are distributed over different brain

Relation of a unified quantum field theory of spinors to the structure of general relativity

International Nuclear Information System (INIS)

Kober, Martin

2009-01-01

Based on a unified quantum field theory of spinors assumed to describe all matter fields and their interactions we construct the space-time structure of general relativity according to a general connection within the corresponding spinor space. The tetrad field and the corresponding metric field are composed from a space-time dependent basis of spinors within the internal space of the fundamental matter field. Similar to twistor theory the Minkowski signature of the space-time metric is related to this spinor nature of elementary matter, if we assume the spinor space to be endowed with a symplectic structure. The equivalence principle and the property of background independence arise from the fact that all elementary fields are composed from the fundamental spinor field. This means that the structure of space-time according to general relativity seems to be a consequence of a fundamental theory of matter fields and not a presupposition as in the usual setting of relativistic quantum field theories.

Einstein's `Z\\"urich Notebook' and his Journey to General Relativity

OpenAIRE

Straumann, Norbert

2011-01-01

On the basis of his `Z\\"urich Notebook' I shall describe a particularly fruitful phase in Einstein's struggle on the way to general relativity. These research notes are an extremely illuminating source for understanding Einstein's main physical arguments and conceptual difficulties that delayed his discovery of general relativity by about three years. Together with the `Ent\\-wurf' theory in collaboration with Marcel Grossmann, these notes also show that the final theory was missed late in 191...

Building the general relativity and gravitation community during the Cold War

CERN Document Server

Lalli, Roberto

2017-01-01

This monograph presents a new perspective on the history of general relativity. It outlines the attempts to establish an institutional framework for the promotion of the field during the Cold War. Readers will learn the difficulties that key figures experienced and overcame during this period of global conflict. The author analyzes the subtle interconnections between scientific and political factors. He shows how politics shaped the evolution of general relativity, even though it is a field with no military applications. He also details how different scientists held quite different views about what “political” meant in their efforts to pursue international cooperation. The narrative examines the specific epistemic features of general relativity that helped create the first official, international scientific society. It answers: Why did relativity bring about this unique result? Was it simply the product of specific actions of particular actors having an illuminated view of international relations in the...

Canonical quantization of general relativity in discrete space-times.

Science.gov (United States)

Gambini, Rodolfo; Pullin, Jorge

2003-01-17

It has long been recognized that lattice gauge theory formulations, when applied to general relativity, conflict with the invariance of the theory under diffeomorphisms. We analyze discrete lattice general relativity and develop a canonical formalism that allows one to treat constrained theories in Lorentzian signature space-times. The presence of the lattice introduces a "dynamical gauge" fixing that makes the quantization of the theories conceptually clear, albeit computationally involved. The problem of a consistent algebra of constraints is automatically solved in our approach. The approach works successfully in other field theories as well, including topological theories. A simple cosmological application exhibits quantum elimination of the singularity at the big bang.

Fetal Growth in Pregnancies Conceived after Gastric Bypass Surgery in Relation to Surgery-to-Conception Interval

DEFF Research Database (Denmark)

Nørgaard, Lone Nikoline; Gjerris, Anne Cathrine Roslev; Kirkegaard, Ida

2014-01-01

Medicine Database). Main outcome measures were early and late fetal growth in relation to time from bariatric surgery to conception of the pregnancy. Early fetal growth was expressed as "Fetal Growth Index": the ratio between the estimated number of days from first trimester ultrasound to second trimester......OBJECTIVE: To describe early and late fetal growth in pregnancies conceived after gastric bypass surgery in relation to time from surgery to conception of pregnancy. METHODS: National cohort study on 387 Danish women, who had laparoscopic or open gastric bypass surgery prior to a singleton...... ultrasound biometries and the actual calender time elapsed in days. Late fetal growth was expressed as the observed versus expected birthweight according to gestational age (GA). RESULTS: The surgery-to-conception interval ranged from 3 to 1851 days with a mean value of 502 (SD, 351) days. The mean "fetal...

Conceptions of Healthy Aging Held by Relatives of Older Persons in Isan-Thai Culture: A Phenomenographic Study.

Science.gov (United States)

Manasatchakun, Pornpun; Roxberg, Åsa; Asp, Margareta

2018-01-01

In Thailand, family nurses are expected to provide support for older persons and their family members to promote healthy aging. Family bonds are strong, and relatives are expected to take care of their older family members. However, there is limited research on how older persons' family members perceive healthy aging. This study aimed to describe the conceptions of healthy aging held by the children and grandchildren of older persons in northeast Thailand. In a phenomenographic study, 14 interviews were performed to qualitatively analyze different conceptions of healthy aging. Four descriptive categories emerged: being independent, not being afflicted by diseases or illnesses, being a giver and a receiver, and being wise. The conceptions of healthy aging entail both autonomy and interdependence. The relative's perspective needs to be considered when policies relating to healthy aging are implemented in the community and when family nurses provide support to families to promote healthy aging.

Generalized polygons

CERN Document Server

Maldeghem, Hendrik

1998-01-01

This book is intended to be an introduction to the fascinating theory ofgeneralized polygons for both the graduate student and the specialized researcher in the field. It gathers together a lot of basic properties (some of which are usually referred to in research papers as belonging to folklore) and very recent and sometimes deep results. I have chosen a fairly strict geometrical approach, which requires some knowledge of basic projective geometry. Yet, it enables one to prove some typically group-theoretical results such as the determination of the automorphism groups of certain Moufang polygons. As such, some basic group-theoretical knowledge is required of the reader. The notion of a generalized polygon is a relatively recent one. But it is one of the most important concepts in incidence geometry. Generalized polygons are the building bricks of Tits buildings. They are the prototypes and precursors of more general geometries such as partial geometries, partial quadrangles, semi-partial ge­ ometries, near...

When being a girl matters less: accessibility of gender-related self-knowledge in single-sex and coeducational classes and its impact on students' physics-related self-concept of ability.

Science.gov (United States)

Kessels, Ursula; Hannover, Bettina

2008-06-01

Establishing or preserving single-sex schooling has been widely discussed as a way of bringing more girls into the natural sciences. We test the assumption that the beneficial effects of single-sex education on girls' self-concept of ability in masculine subjects such as physics are due to the lower accessibility of gender-related self-knowledge in single-sex classes. N=401 eighth-graders (mean age 14.0 years) from coeducational comprehensive schools. Random assignment of students to single-sex vs. coeducational physics classes throughout the eighth grade. At the end of the year, students' physics-related self-concept of ability was measured using a questionnaire. In a subsample of N=134 students, the accessibility of gender-related self-knowledge during physics classes was assessed by measuring latencies and endorsement of sex-typed trait adjectives. Girls from single-sex physics classes reported a better physics-related self-concept of ability than girls from coeducational classes, while boys' self-concept of ability did not vary according to class composition. For both boys and girls, gender-related self-knowledge was less accessible in single-sex classes than in mixed-sex classes. To the extent that girls' feminine self-knowledge was relatively less accessible than their masculine self-knowledge, their physics-related self-concept of ability improved at the end of the school year. By revealing the importance of the differential accessibility of gender-related self-knowledge in single- and mixed-sex settings, our study clarifies why single-sex schooling helps adolescents to gain a better self-concept of ability in school subjects that are considered inappropriate for their own sex.

ACADEMIC TRAINING LECTURE SERIES: Introduction to General Relativity and Black Holes

CERN Multimedia

2003-01-01

10, 11, 12, 13, 14 February ACADEMIC TRAINING LECTURE SERIES from 11.00 to 12.00 hrs - Auditorium, bldg. 500 Introduction to General Relativity and Black Holes by T.DAMOUR, IHES, Bures-sur-Yvette, F - Physical motivation behind Einstein's theory. - Mathematical formalism of General Relativity. - Experimental confirmations of Einstein's theory. - Introduction to Black Holes physics.

Galileons as the Scalar Analogue of General Relativity

NARCIS (Netherlands)

Klein, Remko; Ozkan, Mehmet; Roest, Diederik

2016-01-01

We establish a correspondence between general relativity with diffeomorphism invariance and scalar field theories with Galilean invariance: notions such as the Levi-Civita connection and the Riemann tensor have a Galilean counterpart. This suggests Galilean theories as the unique nontrivial

Equivalent conserved currents and generalized Noether's theorem

International Nuclear Information System (INIS)

Gordon, T.J.

1984-01-01

A generalized Noether theorem is presented, relating symmetries and equivalence classes of local) conservation laws in classical field theories; this is contrasted with the standard theorem. The concept of a ''Noether'' field theory is introduced, being a theory for which the generalized theorem applies; not only does this include the cases of Lagrangian and Hamiltonian field theories, these structures are ''derived'' from the Noether property in a natural way. The generalized theorem applies to currents and symmetries that contain derivatives of the fields up to an arbitrarily high order

Cultural Mediation. The Usefulness of Selected Concepts of Developmental Psychology for Coaching and Mentoring Relations

OpenAIRE

Smorczewska, Barbara

2013-01-01

Some developmental psychological concepts, such as L. S. Vygotsky’s zone of proximal development or H. R. Schaffer’s joint involvement episodes, gave a new perspective in perceiving the process of teaching and development, by providing very detailed characteristics of the situation of acquiring competence in social relations. The mentioned concepts are based on a belief in the developmental potential of humans, and they perceive teaching as future-oriented. These assumptions are also characte...

Singular Null Hypersurfaces in General Relativity

International Nuclear Information System (INIS)

Dray, T

2006-01-01

Null hypersurfaces are a mathematical consequence of the Lorentzian signature of general relativity; singularities in mathematical models usually indicate where the interesting physics takes place. This book discusses what happens when you combine these ideas. Right from the preface, this is a no-nonsense book. There are two principal approaches to singular shells, one distributional and the other 'cut and paste'; both are treated in detail. A working knowledge of GR is assumed, including familiarity with null tetrads, differential forms, and 3 + 1 decompositions. Despite my own reasonably extensive, closely related knowledge, there was material unfamiliar to me already in chapter 3, although I was reunited with some old friends in later chapters. The exposition is crisp, with a minimum of transition from chapter to chapter. In fact, my main criticism is that there is no clear statement of the organization of the book, nor is there an index. Everything is here, and the story is compelling if you know what to look for, although it is less easy to follow the story if you are not already familiar with it. But this is really a book for experts, and the authors certainly qualify, having played a significant role in developing and extending the results they describe. It is also entirely appropriate that the book is dedicated to Werner Israel, who pioneered the thin-shell approach to (non-null) singular surfaces and later championed the use of similar methods for analysing null shells. After an introductory chapter on impulsive signals, the authors show how the Bianchi identities can be used to classify spacetimes with singular null hypersurfaces. This approach, due to the authors, generalizes the framework originally proposed by Penrose. While astrophysical applications are discussed only briefly, the authors point out that detailed physical characteristics of signals from isolated sources can be determined in this manner. In particular, they describe the behaviour of

Two-year study relating adolescents' self-concept and gender role perceptions to achievement and attitudes toward science

Science.gov (United States)

Handley, Herbert M.; Morse, Linda W.

To assess the developmental relationship of perceptions of self-concept and gender role identification with adolescents' attitudes and achievement in science, a two-year longitudinal study was conducted. A battery of instruments assessing 16 dimensions of self-concept/gender role identifications was employed to predict students' achievement and attitudes toward science. Specific behaviors studied included self-concept in school and science and mathematics, attitudes toward appropriate gender roles in science activities and careers, and self-perceptions of masculine and feminine traits. One hundred and fifty-five adolescents, enrolled, respectively, in the seventh and eighth grades, participated in the study. Through Fisher z transformations of correlation coefficients, differences in relationships between these two sets of variables were studied for males and females during the two years. Results indicated that students' self-concepts/gender role perceptions were related to both achievement and attitudes toward science, but more related to attitudes than achievement. These relationships became more pronounced for students as they matured from seventh to eighth graders.

Academic Self-Concept, Achievement Goals, and Achievement: Is Their Relation the Same for Academic Achievers and Underachievers?

Science.gov (United States)

Preckel, Franzis; Brunner, Martin

2015-01-01

This longitudinal study investigated the contribution of achievement goals and academic self-concept for the prediction of unexpected academic achievement (i.e., achievement that is higher or lower than expected with respect to students' cognitive ability) in general and when comparing groups of extreme over- and underachievers. Our sample…

IS IT NECESSARY TO TEACH THE THEORY OF RELATIVITY IN GENERAL PHYSICS COURSE

Directory of Open Access Journals (Sweden)

Sergey N. Kolgatin

2015-01-01

Full Text Available The aim of the present investigation is to discuss and study the general structure of the course of Physics at the high school in an extended sense. In a narrower sense, the author wonders about the necessity for inclusion of the section «Theory of Relativity» in the General Physics course, and discusses the possible site of this issue in the order of presentation.Methods. A method for designing Physics course in modern conditions requires certain sophistication from a lecturer. This is due to the strong reduction of Physics course occurred in recent years, and due to a number of objective and subjective reasons. Planning the course structure, one has to make the selection of most significant questions sacrificing minor and less significant issues. This process is particularly exacerbated by severe restrictions on the time allowed for the subject. It is necessary to re-examine the content of the course due to the recent reduction in lecture hours on Physics. In this case, it would be undesirable to neglect the substantial parts of the subject content which are important conceptually or in its applications, e.g. the Relativity Theory. The author discusses two ways of disposition of the relevant material in the course structure, and correlates them with the required level of Physics teaching. In the first approach the Relativity Theory course is considered as a part of Modern Mechanics and is placed in the first semester immediately following Kinematics. In the second approach, Relativistic Physics is presented as a result of deduction, as a generalized theory explaining the unity of the world and the objective existence of physical laws; in this case, the section is better to locate after Optics, immediately before Atomic Physics.Results. As a result of consideration, the author proves the conclusion that the inclusion of the Relativistic Theory course in a number of sections of General Physics is necessary. The author offers a list of

Relations between Young Students' Strategic Behaviours, Domain-Specific Self-Concept, and Performance in a Problem-Solving Situation

Science.gov (United States)

Dermitzaki, Irini; Leondari, Angeliki; Goudas, Marios

2009-01-01

This study aimed at investigating the relations between students' strategic behaviour during problem solving, task performance and domain-specific self-concept. A total of 167 first- and second-graders were individually examined in tasks involving cubes assembly and in academic self-concept in mathematics. Students' cognitive, metacognitive, and…

Basic Concepts in the Taxonomy of Health-Related Behaviors, Habits and Lifestyle

Science.gov (United States)

Salvador-Carulla, Luis; Alonso, Federico; Gomez, Rafael; Walsh, Carolyn O.; Almenara, José; Ruiz, Mencía; Abellán, María José

2013-01-01

Background: Health-related Habits (HrH) are a major priority in healthcare. However there is little agreement on whether exercise, diet, smoking or dental hygiene are better described as lifestyles, habits or behaviors, and on what is their hierarchical relationship. This research is aimed at representing the basic concepts which are assumed to constitute the conceptual framework enabling us to interpret and organize the field of HrH. Methods: A group of 29 experts with different backgrounds agreed on the definition and hierarchy of HrH following an iterative process which involved framing analysis and nominal group techniques. Results: Formal definitions of health-related behavior, habit, life-style and life-style profile were produced. In addition a series of basic descriptors were identified: health reserve, capital, risk and load. Six main categories of HrH were chosen based on relevance to longevity: diet/exercise, vitality/stress, sleep, cognition, substance use and other risk. Attributes of HrH are clinical meaningfulness, quantifiability, temporal stability, associated morbidity, and unitarity (non-redundancy). Two qualifiers (polarity and stages of change) have also been described. Conclusions: The concepts represented here lay the groundwork for the development of clinical and policy tools related to HrH and lifestyle. An adaptation of this system to define targets of health interventions and to develop the classification of person factors in ICF may be needed in the future. PMID:23670578

Introduction to general relativity and cosmology

CERN Document Server

Berger, Mitchell A

2018-01-01

The textbook aims to present general relativity and modern cosmology in a friendly form suitable for advanced undergraduates. The text begins with a self-contained introduction to the theory of manifolds and then develops the tools needed to understand curved spaces and curved spacetimes. Special relativity can then be understood in a geometrical context, bypassing some of the difficulties students have when encountering relativistic effects (e.g. time dilation and length contraction) for the first time. The theory of curvature and its effects leads to the Einstein field equations and its classic tests in the precession of Mercury and the deflection of starlight. The second part of the book covers modern cosmology, starting with the evolution equations for the expansion of the universe. The microwave background, evidence for dark matter, and the clustering of galaxies are examined in detail.

Universal Dimensions of Meaning Derived from Semantic Relations among Words and Senses: Mereological Completeness vs. Ontological Generality

Directory of Open Access Journals (Sweden)

Alexei V. Samsonovich

2014-07-01

Full Text Available A key to semantic analysis is a precise and practically useful definition of meaning that is general for all domains of knowledge. We previously introduced the notion of weak semantic map: a metric space allocating concepts along their most general (universal semantic characteristics while at the same time ignoring other, domain-specific aspects of their meanings. Here we address questions of the number, quality, and mutual independence of the weak semantic dimensions. Specifically, we employ semantic relationships not previously used for weak semantic mapping, such as holonymy/meronymy (“is-part/member-of”, and we compare maps constructed from word senses to those constructed from words. We show that the “completeness” dimension derived from the holonym/meronym relation is independent of, and practically orthogonal to, the “abstractness” dimension derived from the hypernym-hyponym (“is-a” relation, while both dimensions are orthogonal to the maps derived from synonymy and antonymy. Interestingly, the choice of using relations among words vs. senses implies a non-trivial trade-off between rich and unambiguous information due to homonymy and polysemy. The practical utility of the new and prior dimensions is illustrated by the automated evaluation of different kinds of documents. Residual analysis of available linguistic resources, such as WordNet, suggests that the number of universal semantic dimensions representable in natural language may be finite. Their complete characterization, as well as the extension of results to non-linguistic materials, remains an open challenge.

Relativity the theory and its philosophy

CERN Document Server

Angel, Roger B

1980-01-01

Relativity: The Theory and its Philosophy provides a completely self-contained treatment of the philosophical foundations of the theory of relativity. It also surveys the most essential mathematical techniques and concepts that are indispensable to an understanding of the foundations of both the special and general theories of relativity. In short, the book includes a crash course in applied mathematics, ranging from elementary trigonometry to the classical tensor calculus.Comprised of 11 chapters, this book begins with an introduction to fundamental mathematical concepts such as sets, relatio

Academic Training: Einstein and beyond: Introduction to General relativity

CERN Multimedia

Françoise Benz

2005-01-01

2005-2006 ACADEMIC TRAINING PROGRAMME LECTURE SERIES 3, 4, 5, 6, 7 October from 11:00 to 12:00 - Main Auditorium, bldg. 500 Einstein and beyond: Introduction to General relativity by N. Straumann / Institut fur theoretische physics, Univ. Zürich We review the enduring achievements of Einstein's papers of 1905 and their impact on the further developments in physics. Program : Lectures I and II:Einstein's Contributions to Statistical Mechanics and Quantum Theory Lecture III:Einstein's Thesis at the University of Zürich Lecture IV: From Special to General Relativity Lecture V: The History and the Mystery of the Cosmological Constant ENSEIGNEMENT ACADEMIQUE ACADEMIC TRAINING Françoise Benz 73127 academic.training@cern.ch

Proceedings of the fourth Marcel Grossmann meeting on general relativity

International Nuclear Information System (INIS)

Ruffini, R.

1986-01-01

The Marcel Grossmann meetings were conceived with the aim of reviewing recent advances in gravitation and general relativity with the major emphasis on their mathematical foundations and physical predictions. Their main objective is to elicit contributions which deepen our understanding of space-time structures as well as to review the status of experiments verifying Einstein's Theory of Gravitation. It has been demonstrated by the previous meetings that these sessions provide physicists from various countries who are involved in research on general relativity with a unique opportunity to exchange experiences and enhance co-operation in fields of common interest. The meeting was essentially divided into 3 sub-areas; interplay between elementary particle physics and cosmology and relativistic astrophysics, classical relativity, and experimental relativity. Among the topics covered were supergravity and superstrings, bar gravitational wave detectors, black holes, classical relativity, computer relativity, cosmology and inos, early cosmology, exact solutions, Kaluza Klein theories, relativistic self-gravitating systems and quantum gravity. (Auth.)

Tests of general relativity from timing the double pulsar.

Science.gov (United States)

Kramer, M; Stairs, I H; Manchester, R N; McLaughlin, M A; Lyne, A G; Ferdman, R D; Burgay, M; Lorimer, D R; Possenti, A; D'Amico, N; Sarkissian, J M; Hobbs, G B; Reynolds, J E; Freire, P C C; Camilo, F

2006-10-06

The double pulsar system PSR J0737-3039A/B is unique in that both neutron stars are detectable as radio pulsars. They are also known to have much higher mean orbital velocities and accelerations than those of other binary pulsars. The system is therefore a good candidate for testing Einstein's theory of general relativity and alternative theories of gravity in the strong-field regime. We report on precision timing observations taken over the 2.5 years since its discovery and present four independent strong-field tests of general relativity. These tests use the theory-independent mass ratio of the two stars. By measuring relativistic corrections to the Keplerian description of the orbital motion, we find that the "post-Keplerian" parameter s agrees with the value predicted by general relativity within an uncertainty of 0.05%, the most precise test yet obtained. We also show that the transverse velocity of the system's center of mass is extremely small. Combined with the system's location near the Sun, this result suggests that future tests of gravitational theories with the double pulsar will supersede the best current solar system tests. It also implies that the second-born pulsar may not have formed through the core collapse of a helium star, as is usually assumed.

Lateral Concepts

DEFF Research Database (Denmark)

Gad, Christopher; Bruun Jensen, casper

2016-01-01

This essay discusses the complex relation between the knowledges and practices of the researcher and his/her informants in terms of lateral concepts. The starting point is that it is not the prerogative of the (STS) scholar to conceptualize the world; all our “informants” do it too. This creates...... the possibility of enriching our own conceptual repertoires by letting them be inflected by the concepts of those we study. In a broad sense, the lateral means that there is a many-to-many relation between domains of knowledge and practice. However, each specific case of the lateral is necessarily immanent...... to a particular empirical setting and form of inquiry. In this sense lateral concepts are radically empirical since it locates concepts within the field. To clarify the meaning and stakes of lateral concepts, we first make a contrast between lateral anthropology and Latour’s notion of infra-reflexivity. We end...

Relational autonomy in informed consent (RAIC) as an ethics of care approach to the concept of informed consent.

Science.gov (United States)

Osuji, Peter I

2018-03-01

The perspectives of the dominant Western ethical theories, have dominated the concepts of autonomy and informed consent for many years. Recently this dominant understanding has been challenged by ethics of care which, although, also emanates from the West presents a more nuanced concept: relational autonomy, which is more faithful to our human experience. By paying particular attention to relational autonomy, particularity and Process approach to ethical deliberations in ethics of care, this paper seeks to construct a concept of informed consent from the perspective of ethics of care which is here called relational autonomy-in-informed consent (RAIC). Thus, providing a broader theoretical basis for informed consent beyond the usual theoretical perspectives that are particularly Western. Care ethics provides such a broader basis because it appeals to a global perspective that encompasses lessons from other cultures, and this will help to enrich the current ideas of bioethics principles of autonomy and informed consent. This objective will be achieved by exploring the ethics of care emphasis on relationships based on a universal experience of caring; and by contrasting its concept of autonomy as relational with the understanding of autonomy in the approaches of the dominant moral theories that reflect rational, individualistic, and rights-oriented autonomy of the American liberalism.

Escape trajectories of solar sails and general relativity

Energy Technology Data Exchange (ETDEWEB)

Kezerashvili, Roman Ya. [Physics Department, New York City College of Technology, City University of New York, 300 Jay Street, Brooklyn, NY 11201 (United States); Graduate School and University Center, City University of New York, 365 Fifth Avenue, New York, NY 10016 (United States); Vazquez-Poritz, Justin F., E-mail: jvazquez-poritz@citytech.cuny.ed [Physics Department, New York City College of Technology, City University of New York, 300 Jay Street, Brooklyn, NY 11201 (United States); Graduate School and University Center, City University of New York, 365 Fifth Avenue, New York, NY 10016 (United States)

2009-11-16

General relativity can have a significant impact on the long-range escape trajectories of solar sails deployed near the sun. For example, spacetime curvature in the vicinity of the sun can cause a solar sail traveling from about 4 solar radii to 2550 AU to be deflected by on the order of a million kilometers, and should therefore be taken into account at the beginning of the mission. There are a number of smaller general relativistic effects, such as frame dragging due to the slow rotation of the sun which can cause a deflection of more than one thousand kilometers.

Escape trajectories of solar sails and general relativity

International Nuclear Information System (INIS)

Kezerashvili, Roman Ya.; Vazquez-Poritz, Justin F.

2009-01-01

General relativity can have a significant impact on the long-range escape trajectories of solar sails deployed near the sun. For example, spacetime curvature in the vicinity of the sun can cause a solar sail traveling from about 4 solar radii to 2550 AU to be deflected by on the order of a million kilometers, and should therefore be taken into account at the beginning of the mission. There are a number of smaller general relativistic effects, such as frame dragging due to the slow rotation of the sun which can cause a deflection of more than one thousand kilometers.

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

Science.gov (United States)

Koponen, Ismo; Nousiainen, Maija

2013-01-01

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

Cultural Mediation. The Usefulness of Selected Concepts of Developmental Psychology for Coaching and Mentoring Relations

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Barbara Smorczewska

2013-09-01

Full Text Available Some developmental psychological concepts, such as L. S. Vygotsky’s zone of proximal development or H. R. Schaffer’s joint involvement episodes, gave a new perspective in perceiving the process of teaching and development, by providing very detailed characteristics of the situation of acquiring competence in social relations. The mentioned concepts are based on a belief in the developmental potential of humans, and they perceive teaching as future-oriented. These assumptions are also characteristic for coaching and mentoring which are nowadays becoming more and more popular forms of development in work places; hence an attempt to find some analogy between them. The prepared comparison contributes to extending the theoretical bases of “development cooperation relations,” as coaching and mentoring are jointly referred to.

Further Generalization of Golden Mean in Relation to Euler Divine Equation

OpenAIRE

Rakocevic, Miloje M.

2006-01-01

In the paper a new generalization of the Golden mean, as a further generalization in relation to Stakhov (1989) and to Spinadel (1999), is presented. Also it is first observed that the Euler divine equation represents a possible generalization of Golden mean. In this second version the Section 6 is added.

On the learning difficulty of visual and auditory modal concepts: Evidence for a single processing system.

Science.gov (United States)

Vigo, Ronaldo; Doan, Karina-Mikayla C; Doan, Charles A; Pinegar, Shannon

2018-02-01

The logic operators (e.g., "and," "or," "if, then") play a fundamental role in concept formation, syntactic construction, semantic expression, and deductive reasoning. In spite of this very general and basic role, there are relatively few studies in the literature that focus on their conceptual nature. In the current investigation, we examine, for the first time, the learning difficulty experienced by observers in classifying members belonging to these primitive "modal concepts" instantiated with sets of acoustic and visual stimuli. We report results from two categorization experiments that suggest the acquisition of acoustic and visual modal concepts is achieved by the same general cognitive mechanism. Additionally, we attempt to account for these results with two models of concept learning difficulty: the generalized invariance structure theory model (Vigo in Cognition 129(1):138-162, 2013, Mathematical principles of human conceptual behavior, Routledge, New York, 2014) and the generalized context model (Nosofsky in J Exp Psychol Learn Mem Cogn 10(1):104-114, 1984, J Exp Psychol 115(1):39-57, 1986).

Spacecraft Tests of General Relativity

Science.gov (United States)

Anderson, John D.

1997-01-01

Current spacecraft tests of general relativity depend on coherent radio tracking referred to atomic frequency standards at the ground stations. This paper addresses the possibility of improved tests using essentially the current system, but with the added possibility of a space-borne atomic clock. Outside of the obvious measurement of the gravitational frequency shift of the spacecraft clock, a successor to the suborbital flight of a Scout D rocket in 1976 (GP-A Project), other metric tests would benefit most directly by a possible improved sensitivity for the reduced coherent data. For purposes of illustration, two possible missions are discussed. The first is a highly eccentric Earth orbiter, and the second a solar-conjunction experiment to measure the Shapiro time delay using coherent Doppler data instead of the conventional ranging modulation.

Defining According to Its Essence: An Analysis on the Concept of Tong Shi Education (General Education) in the Native Chinese Context

Science.gov (United States)

Lu, Yi; Xu, Yuan

2018-01-01

The authors review the concept of Tong Shi (Chinese characters omitted) in ancient Chinese philosophical texts, illustrate the Chinese cultural attributes unique to the characters Tong and Shi, and confirm that the name and essence of Tong Shi Education has a clear directivity and irreplaceable coverage to university general education in…

Cross-cultural differences in children's concepts of health and illness

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Boruchovitch Evely

1997-01-01

Full Text Available INTRODUCTION: In spite of general agreement that cross-cultural research is needed in the health area, most existing investigations of children's development of health and illness-related concepts have involved samples from developed countries. The study examined the development of the concepts of health and illness as a function of subject's age, socio-economic status (SES, gender and grade level in a Brazilian sample of 96 elementary and junior high school students. METHODS: Subjects were interviewed individually and their ideas of health and illness were assessed through open-ended questions. Participants' answers were transcribed verbatim and subjected to content analysis. RESULTS: Chi-square analyses revealed significant age, school grade and SES-related differences in participants' concepts of health and illness. DISCUSSION AND CONCLUSION: The themes employed by subjects to define both health and illness were broadly consistent with those found by previous research. The study showed a predictable relationship between subject's age and school grade level and increasingly more highly differentiated and multidimensional concepts of health and illness. This investigation suggests that, for the most part, cross-cultural similarities in children's concepts of health and illness may be more striking than the differences.

Cross-cultural differences in children's concepts of health and illness

Directory of Open Access Journals (Sweden)

Evely Boruchovitch

1997-10-01

Full Text Available INTRODUCTION: In spite of general agreement that cross-cultural research is needed in the health area, most existing investigations of children's development of health and illness-related concepts have involved samples from developed countries. The study examined the development of the concepts of health and illness as a function of subject's age, socio-economic status (SES, gender and grade level in a Brazilian sample of 96 elementary and junior high school students. METHODS: Subjects were interviewed individually and their ideas of health and illness were assessed through open-ended questions. Participants' answers were transcribed verbatim and subjected to content analysis. RESULTS: Chi-square analyses revealed significant age, school grade and SES-related differences in participants' concepts of health and illness. DISCUSSION AND CONCLUSION: The themes employed by subjects to define both health and illness were broadly consistent with those found by previous research. The study showed a predictable relationship between subject's age and school grade level and increasingly more highly differentiated and multidimensional concepts of health and illness. This investigation suggests that, for the most part, cross-cultural similarities in children's concepts of health and illness may be more striking than the differences.

Development of Smart Sensors System Based on Formal Concept Analysis and Ontology Model

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Hongsheng Xu

2013-06-01

Full Text Available The smart sensor is the product of the combination of one or more sensitive components, precision analog circuits, digital circuits, microprocessor, communication interface, intelligent software systems and hardware integration in a packaging component. Formal concept analysis is from the given data to automatically extract the classification relationship between the entire hidden concept and concept, formation of concept model. Ontology is a set of relations between concepts of the specific domain and concept, and it can effectively express the general knowledge of specific field. The paper proposes development of smart sensors system based on formal concept analysis and ontology model. Smart sensor is a micro processor, sensor with information detection, information processing, information memory, logical thinking and judging function. The methods can improve the effect of the smart sensors.

Spinning fluids in general relativity: a variational formulation

International Nuclear Information System (INIS)

Oliveira, H.P. de; Salim, J.M.

1990-01-01

In this paper we present a variational formulation for spinning fluids in General Relativity. In our model each volume element of the fluid has rigid microstructure. We deduce a symmetrical energy-moment tensor where there is an explicit contribution of kinetic spin energy to the total energy. (author)

New Area Law in General Relativity.

Science.gov (United States)

Bousso, Raphael; Engelhardt, Netta

2015-08-21

We report a new area law in general relativity. A future holographic screen is a hypersurface foliated by marginally trapped surfaces. We show that their area increases monotonically along the foliation. Future holographic screens can easily be found in collapsing stars and near a big crunch. Past holographic screens exist in any expanding universe and obey a similar theorem, yielding the first rigorous area law in big bang cosmology. Unlike event horizons, these objects can be identified at finite time and without reference to an asymptotic boundary. The Bousso bound is not used, but it naturally suggests a thermodynamic interpretation of our result.

Mathematica for Theoretical Physics: Electrodynamics, Quantum Mechanics, General Relativity and Fractals

International Nuclear Information System (INIS)

Heusler, Stefan

2006-01-01

The main focus of the second, enlarged edition of the book Mathematica for Theoretical Physics is on computational examples using the computer program Mathematica in various areas in physics. It is a notebook rather than a textbook. Indeed, the book is just a printout of the Mathematica notebooks included on the CD. The second edition is divided into two volumes, the first covering classical mechanics and nonlinear dynamics, the second dealing with examples in electrodynamics, quantum mechanics, general relativity and fractal geometry. The second volume is not suited for newcomers because basic and simple physical ideas which lead to complex formulas are not explained in detail. Instead, the computer technology makes it possible to write down and manipulate formulas of practically any length. For researchers with experience in computing, the book contains a lot of interesting and non-trivial examples. Most of the examples discussed are standard textbook problems, but the power of Mathematica opens the path to more sophisticated solutions. For example, the exact solution for the perihelion shift of Mercury within general relativity is worked out in detail using elliptic functions. The virial equation of state for molecules' interaction with Lennard-Jones-like potentials is discussed, including both classical and quantum corrections to the second virial coefficient. Interestingly, closed solutions become available using sophisticated computing methods within Mathematica. In my opinion, the textbook should not show formulas in detail which cover three or more pages-these technical data should just be contained on the CD. Instead, the textbook should focus on more detailed explanation of the physical concepts behind the technicalities. The discussion of the virial equation would benefit much from replacing 15 pages of Mathematica output with 15 pages of further explanation and motivation. In this combination, the power of computing merged with physical intuition would

Gauge stability of 3+1 formulations of general relativity

International Nuclear Information System (INIS)

Khokhlov, A M; Novikov, I D

2002-01-01

We present a general approach to the analysis of gauge stability of 3+1 formulations of general relativity (GR). Evolution of coordinate perturbations and the corresponding perturbations of lapse and shift can be described by a system of eight quasi-linear partial differential equations. Stability with respect to gauge perturbations depends on the choice of gauge and a background metric, but it does not depend on a particular form of a 3+1 system if its constrained solutions are equivalent to those of the Einstein equations. Stability of a number of known gauges is investigated in the limit of short-wavelength perturbations. All fixed gauges except a synchronous gauge are found to be ill posed. A maximal slicing gauge and its parabolic extension are shown to be ill posed as well. A necessary condition is derived for well-posedness of metric-dependent algebraic gauges. Well-posed metric-dependent gauges are found, however, to be generally unstable. Both instability and ill-posedness are associated with the existence of growing modes of coordinate perturbations related to perturbations of physical accelerations of reference frames

Theta-Generalized closed sets in fuzzy topological spaces

International Nuclear Information System (INIS)

El-Shafei, M.E.; Zakari, A.

2006-01-01

In this paper we introduce the concepts of theta-generalized closed fuzzy sets and generalized fuzzy sets in topological spaces. Furthermore, generalized fuzzy sets are extended to theta-generalized fuzzy sets. Also, we introduce the concepts of fuzzy theta-generalized continuous and fuzzy theta-generalized irresolute mappings. (author)

Causal modeling of self-concept, job satisfaction, and retention of nurses.

Science.gov (United States)

Cowin, Leanne S; Johnson, Maree; Craven, Rhonda G; Marsh, Herbert W

2008-10-01

The critical shortage of nurses experienced throughout the western world has prompted researchers to examine one major component of this complex problem - the impact of nurses' professional identity and job satisfaction on retention. A descriptive correlational design with a longitudinal element was used to examine a causal model of nurses' self-concept, job satisfaction, and retention plans in 2002. A random sample of 2000 registered nurses was selected from the state registering authority listing. A postal survey assessing multiple dimensions of nurses' self-concept (measured by the nurse self-concept questionnaire), job satisfaction (measured by the index of work satisfaction) was undertaken at Time 1 (n=528) and 8 months later at Time 2 (n=332) (including retention plans (measured by the Nurse Retention Index). Using confirmatory factor analysis, correlation matrices and path analysis, measurement and structural models were examined on matching pairs of data from T1 and T2 (total sample N=332). Nurses' self-concept was found to have a stronger association with nurses' retention plans (B=.45) than job satisfaction (B=.28). Aspects of pay and task were not significantly related to retention plans, however, professional status (r=.51), and to a lesser extent, organizational policies (r=.27) were significant factors. Nurses' general self-concept was strongly related (r=.57) to retention plans. Strategies or interventions requiring implementation and evaluation include: counseling to improve nurse general self-concept, education programs and competencies in health communication between health professionals, reporting of nurse-initiated programs with substantial patient benefit, nurse-friendly organizational policies, common health team learning opportunities, and autonomous practice models.