Recalculation of the unitary single planar dual loop in the critical dimension of space time
Brink, L
1973-01-01
The single planar dual-loop amplitudes are recalculated in the critical dimension of space time paying particular attention to the unitarity property by ensuring that the only states propagating internally in the loop are those needed to factorize tree diagram residues in a positive definite way. The two new technical features which make this possible are (i) a newly discovered physical state projection operator valid if the space- time dimension takes the critical value; (ii) the use of Feynman's tree theorem whereby it is sufficient to have the above projection operator on the mass shell. The final result agrees with a previous conjecture in that it differs from the original calculations with unprojected propagators by two inverse power of a certain partition function. The results apply to both the ordinary dual model and the Neveu-Schwarz model. (12 refs).
DEFF Research Database (Denmark)
Clausen, Anders; Hu, Hao; Ye, Feihong
2015-01-01
Increasing the capacity of optical networks while have the objective of lowering the total consumed energy per bit is challenging. By exploiting several dimensions, i.e. wavelength, space, time, polarisation and multilevel modulation simultaneously, a single laser can offer formidable capacity pe...
Lincoln, Don
2013-01-01
They say that there is no such thing as a stupid question. In a pedagogically pure sense, that's probably true. But some questions do seem to flirt dangerously close to being really quite ridiculous. One such question might well be, "How many dimensions of space are there?" I mean, it's pretty obvious that there are three:…
Effective dimension in some general metric spaces
Directory of Open Access Journals (Sweden)
Elvira Mayordomo
2014-03-01
Full Text Available We introduce the concept of effective dimension for a general metric space. Effective dimension was defined by Lutz in (Lutz 2003 for Cantor space and has also been extended to Euclidean space. Our extension to other metric spaces is based on a supergale characterization of Hausdorff dimension. We present here the concept of constructive dimension and its characterization in terms of Kolmogorov complexity. Further research directions are indicated.
search of extra space dimensions with ATLAs
Indian Academy of Sciences (India)
search of extra space dimensions with ATLAs. AMBREEsH GUPTA (for the ATLAs Collaboration). 5640 South Ellis Avenue, Enrico Fermi Institute, University of Chicago, Chicago,. IL 60637, USA. Abstract. If extra spatial dimensions were to exist, they could provide a solution to the hierarchy problem. The studies done by the ...
Fractals and universal spaces in dimension theory
Lipscomb, Stephen
2009-01-01
Historically, for metric spaces the quest for universal spaces in dimension theory spanned approximately a century of mathematical research. The history breaks naturally into two periods - the classical (separable metric) and the modern (not-necessarily separable metric). This book unifies the modern theory from 1960-2007.
Moduli space for endomorphisms of finite dimension vector spaces
International Nuclear Information System (INIS)
Kanarek, H.
1990-12-01
Consider the set (End n ) of endomorphisms of vector spaces of dimension n n ). What we present here is a decomposition of (End n ) in which each element has a fine moduli space and one of them is composed by the semisimple endomorphisms as D. Mumford shows. (author). 2 refs
On the Spaces and Dimensions of Geographical Systems
Chen, Yanguang
2011-01-01
To remove the confusion of concepts about different sorts of geographical space and dimension, a new framework of space theory is proposed in this paper. Based on three sets of fractal dimensions, the geographical space is divided into three types: real space (R-space), phase space (P-space), and order space (O-space). The real space is concrete or visual space, the fractal dimension of which can be evaluated through digital maps or remotely sensed images. The phase space and order space are ...
Fractal dimension of interfaces in Edwards-Anderson spin glasses for up to six space dimensions
Wang, Wenlong; Moore, M. A.; Katzgraber, Helmut G.
2018-03-01
The fractal dimension of domain walls produced by changing the boundary conditions from periodic to antiperiodic in one spatial direction is studied using both the strong-disorder renormalization group algorithm and the greedy algorithm for the Edwards-Anderson Ising spin-glass model for up to six space dimensions. We find that for five or fewer space dimensions, the fractal dimension is lower than the space dimension. This means that interfaces are not space filling, thus implying that replica symmetry breaking is absent in space dimensions fewer than six. However, the fractal dimension approaches the space dimension in six dimensions, indicating that replica symmetry breaking occurs above six dimensions. In two space dimensions, the strong-disorder renormalization group results for the fractal dimension are in good agreement with essentially exact numerical results, but the small difference is significant. We discuss the origin of this close agreement. For the greedy algorithm there is analytical expectation that the fractal dimension is equal to the space dimension in six dimensions and our numerical results are consistent with this expectation.
Coset space dimension reduction of gauge theories
International Nuclear Information System (INIS)
Farakos, K.; Kapetanakis, D.; Koutsoumbas, G.; Zoupanos, G.
1989-01-01
A very interesting approach in the attempts to unify all the interactions is to consider that a unification takes place in higher than four dimensions. The most ambitious program based on the old Kaluza-Klein idea is not able to reproduce the low energy chiral nature of the weak interactions. A suggested way out was the introduction of Yang-Mills fields in the higher dimensional theory. From the particle physics point of view the most important question is how such a theory behaves in four dimensions and in particular in low energies. Therefore most of our efforts concern studies of the properties of an attractive scheme, the Coset-Space-Dimensional-Reduction (C.S.D.R.) scheme, which permits the study of the effective four dimensional theory coming from a gauge theory defined in higher dimensions. Here we summarize the C.S.D.R. procedure the main the rems which are obeyed and to present a realistic model which is the result of the model building efforts that take into account all the C.S.D.R. properties. (orig./HSI)
Extra dimensions in space and time
Bars, Itzhak
2010-01-01
Covers topics such as Einstein and the Fourth Dimension; Waves in a Fifth Dimension; and String Theory and Branes Experimental Tests of Extra Dimensions. This book offers a discussion on Two-Time Physics
search of extra space dimensions with ATLAs
Indian Academy of Sciences (India)
If extra spatial dimensions were to exist, they could provide a solution to the hierarchy problem. The studies done by the ATLAS Collaboration on the sensitivity of the detector to various extra dimension models are reported in this document. Author Affiliations. Ambreesh Gupta1 ATLAS Collaboration. 5640 South Ellis ...
Hydrogen equation in spaces of arbitrary dimensions
International Nuclear Information System (INIS)
Amusia, M Ya
2015-01-01
We note that presenting Hydrogen atom Schrodinger equation in the case of arbitrary dimensions require simultaneous modification of the Coulomb potential that only in three dimensions has the form Z / r. This was not done in a number of relatively recent papers (see [1] and references therein). Therefore, some results obtained in [1] seem to be doubtful. Several required considerations in the area are mentioned. (paper)
BIM: Dimensions of Space, Thought, and Education
Directory of Open Access Journals (Sweden)
Luigi Cocchiarella
2016-06-01
Full Text Available Much of the aim of present epistemology seems to deal with filling the gap between analogue traditional and digital practices, which for a long time have been considered profoundly opposite, with heavy consequences in terms of integrity of knowledge.BIM is among the most representative cases in this discussion. Able to integrate and compute several sets of parameters and algorithms, it shows a clear picture of the interdisciplinary opportunities which are connected with by smart use of its devices. It is not by chance that it is expected to be the standard operational format in the fields of Architecture, Engineering, and Design. The quintessence of BIM is in its many dimensions, which are not only digital dimensions, but also dimensions of knowledge.
Synthetic space with arbitrary dimensions in a few rings undergoing dynamic modulation
Yuan, Luqi; Xiao, Meng; Lin, Qian; Fan, Shanhui
2018-03-01
We show that a single ring resonator undergoing dynamic modulation can be used to create a synthetic space with an arbitrary dimension. In such a system, the phases of the modulation can be used to create a photonic gauge potential in high dimensions. As an illustration of the implication of this concept, we show that the Haldane model, which exhibits nontrivial topology in two dimensions, can be implemented in the synthetic space using three rings. Our results point to a route toward exploring higher-dimensional topological physics in low-dimensional physical structures. The dynamics of photons in such synthetic spaces also provides a mechanism to control the spectrum of light.
A version of superstring with four space-time dimensions
International Nuclear Information System (INIS)
Dao Vong Duc; Nguyen Hong Ha; Nguyen Lan Oanh.
1992-08-01
We consider a version of reducing the critical dimension of space-time for superstrings based on the internal symmetry group O(p,q). The new additional oscillators used are antisymmetric second rank tensors associated with this group. The model admits the solution without extra spatial dimension. (author). 9 refs
Nonlinear damped Schrodinger equation in two space dimensions
Directory of Open Access Journals (Sweden)
Tarek Saanouni
2015-04-01
Full Text Available In this article, we study the initial value problem for a semi-linear damped Schrodinger equation with exponential growth nonlinearity in two space dimensions. We show global well-posedness and exponential decay.
Existence dimension of media-educational space
Directory of Open Access Journals (Sweden)
B. V. Bratanich
2014-03-01
Full Text Available The world media culture is the everyday existential context of selfidentity. Entry into the media culture turns and practice, and by the adequate development of the problem field of human existence. Education as a way to selfdetermine human ways and purposes of entry into the modern media culture in the field of communication and interaction with other people, mediated by electronic media. In the presence of global media space fundamental information plays a crucial role in socialization, is formed at the intersection of the education system and the electronic media, which gives grounds to determine exactly mediaeducational community primary medium of socialization in the age of online media. Media education environment creates more favorable conditions to educational activities has become a way of selfidentity, as it results of creative activity of the subject taken by others as taking it himself, his personality. Its major advantage as space being is to provide the maximum activity of the individual in determining the trajectory of development. A common basis for resolving the risks socialization and being the person in the media education area are the values and goals of selfdevelopment, formulated within postmodern education.
Weyl-Wigner correspondence in two space dimensions
DEFF Research Database (Denmark)
Dahl, Jens Peder; Varro, S.; Wolf, A.
2007-01-01
We consider Wigner functions in two space dimensions. In particular, we focus on Wigner functions corresponding to energy eigenstates of a non-relativistic particle moving in two dimensions in the absence of a potential. With the help of the Weyl-Wigner correspondence we first transform the eigen...... the eigenvalue equations for energy and angular momentum into phase space. As a result we arrive at partial differential equations in phase space which determine the corresponding Wigner function. We then solve the resulting equations using appropriate coordinates....
Toward de Sitter space from ten dimensions
Moritz, Jakob; Retolaza, Ander; Westphal, Alexander
2018-02-01
Using a 10D lift of nonperturbative volume stabilization in type IIB string theory, we study the limitations for obtaining de Sitter vacua. Based on this we find that the simplest Kachru, Kallosh, Linde, and Trivedi vacua with a single Kähler modulus stabilized by a gaugino condensate cannot be uplifted to de Sitter. Rather, the uplift flattens out due to stronger backreaction on the volume modulus than has previously been anticipated, resulting in vacua which are metastable and supersymmetry breaking, but that are always anti-de Sitter (AdS). However, we also show that setups such as racetrack stabilization can avoid this issue. In these models it is possible to obtain supersymmetric AdS vacua with a cosmological constant that can be tuned to zero while retaining finite moduli stabilization. In this regime, it seems that de Sitter uplifts are possible with negligible backreaction on the internal volume. We exhibit this behavior also from the 10D perspective.
Determining the minimum embedding dimension for state space ...
Indian Academy of Sciences (India)
Abstract. The analysis of observed time series from nonlinear systems is usually done by making a time-delay reconstruction to unfold the dynamics on a multidimensional state space. An important aspect of the analysis is the choice of the correct embedding dimension. The conventional procedure used for this is either the ...
Fermions in odd space-time dimensions: back to basics
International Nuclear Information System (INIS)
Anguiano Jesus de, Ma.; Bashir, A.
2005-01-01
It is a well-known feature of odd space-time dimensions d that there exist two inequivalent fundamental representations A and B of the Dirac gamma matrices. Moreover, the parity transformation swaps the fermion fields living in A and B. As a consequence, a parity-invariant Lagrangian can only be constructed by incorporating both the representation. Based upon these ideas and contrary to long-held belief, we show that in addition to a discrete exchange symmetry for the massless case, we can also define chiral symmetry provided the Lagrangian contains fields corresponding to both the inequivalent representations. We also study the transformation properties of the corresponding chiral currents under parity and charge-conjugation operations. We work explicitly in 2 + 1 dimensions and later show how some of these ideas generalize to an arbitrary number of odd dimensions. (author)
GLOBAL AND INSULAR DIMENSIONS: SPACE IN SARDINIA BLUES
Directory of Open Access Journals (Sweden)
Ana Maria Chiarini
2010-11-01
Full Text Available The aim of this work is to focus attention on the dimension of space in Sardinia Blues (Publisher Bompiani, 2008, by Flavio Soriga. This is justified by the centrality of space throughout the novel and by the title itself. The island of Sardinia is not just a mere setting, but it is most importantly the articulating and conducting thread for all the themes related to the characters’ self-identity and existential issues. The regional Sardinian space, perceived as stereotyped and folkloristic, and the global space, seen as a source of both desire and fear, are problematized by the three young self-proclaimed “pirates of the island” in their long hours of idleness. It is our intention to highlight the conflicts of this marginal insular condition, heavily contaminated by an inevitable process of change, in Soriga’s simultaneously innovative and nostalgic fragmented text, filled with songs’ extracts and languages hybrids.
TVD schemes in one and two space dimensions
International Nuclear Information System (INIS)
Leveque, R.J.; Goodman, J.B.; New York Univ., NY)
1985-01-01
The recent development of schemes which are second order accurate in smooth regions has made it possible to overcome certain difficulties which used to arise in numerical computations of discontinuous solutions of conservation laws. The present investigation is concerned with scalar conservation laws, taking into account the employment of total variation diminishing (TVD) schemes. The concept of a TVD scheme was introduced by Harten et al. (1976). Harten et al. first constructed schemes which are simultaneously TVD and second order accurate on smooth solutions. In the present paper, a summary is provided of recently conducted work in this area. Attention is given to TVD schemes in two space dimensions, a second order accurate TVD scheme in one dimension, and the entropy condition and spreading of rarefaction waves. 19 references
Unifying model for random matrix theory in arbitrary space dimensions
Cicuta, Giovanni M.; Krausser, Johannes; Milkus, Rico; Zaccone, Alessio
2018-03-01
A sparse random block matrix model suggested by the Hessian matrix used in the study of elastic vibrational modes of amorphous solids is presented and analyzed. By evaluating some moments, benchmarked against numerics, differences in the eigenvalue spectrum of this model in different limits of space dimension d , and for arbitrary values of the lattice coordination number Z , are shown and discussed. As a function of these two parameters (and their ratio Z /d ), the most studied models in random matrix theory (Erdos-Renyi graphs, effective medium, and replicas) can be reproduced in the various limits of block dimensionality d . Remarkably, the Marchenko-Pastur spectral density (which is recovered by replica calculations for the Laplacian matrix) is reproduced exactly in the limit of infinite size of the blocks, or d →∞ , which clarifies the physical meaning of space dimension in these models. We feel that the approximate results for d =3 provided by our method may have many potential applications in the future, from the vibrational spectrum of glasses and elastic networks to wave localization, disordered conductors, random resistor networks, and random walks.
Effect of prolonged space flight on cardiac function and dimensions
Henry, W. L.; Epstein, S. E.; Griffith, J. M.; Goldstein, R. E.; Redwood, D. R.
1974-01-01
Echocardiographic studies were performed preflight 5 days before launch and on recovery day and 1, 2, 4, 11, 31 and 68 days postflight. From these echocardiograms measurements were made. From these primary measurements, left ventricular end-diastolic volume, end-systolic volume, stroke volume, and mass were derived using the accepted assumptions. Findings in the Scientist Pilot and Pilot resemble those seen in trained distance runners. Wall thickness measurements were normal in all three crewmembers preflight. Postflight basal studies were unchanged in the Commander on recovery day through 68 days postflight in both the Scientist Pilot and Pilot, however, the left ventricular end-diastolic volume, stroke volume, and mass were decreased slightly. Left ventricular function curves were constructed for the Commander and Pilot by plotting stroke volume versus end-diastolic volume. In both astronauts, preflight and postflight data fell on the same straight line demonstrating that no deterioration in cardiac function had occurred. These data indicate that the cardiovascular system adapts well to prolonged weightlessness and suggest that alterations in cardiac dimensions and function are unlikely to limit man's future in space.
Symmetric Space Cartan Connections and Gravity in Three and Four Dimensions
Directory of Open Access Journals (Sweden)
Derek K. Wise
2009-08-01
Full Text Available Einstein gravity in both 3 and 4 dimensions, as well as some interesting generalizations, can be written as gauge theories in which the connection is a Cartan connection for geometry modeled on a symmetric space. The relevant models in 3 dimensions include Einstein gravity in Chern-Simons form, as well as a new formulation of topologically massive gravity, with arbitrary cosmological constant, as a single constrained Chern-Simons action. In 4 dimensions the main model of interest is MacDowell-Mansouri gravity, generalized to include the Immirzi parameter in a natural way. I formulate these theories in Cartan geometric language, emphasizing also the role played by the symmetric space structure of the model. I also explain how, from the perspective of these Cartan-geometric formulations, both the topological mass in 3d and the Immirzi parameter in 4d are the result of non-simplicity of the Lorentz Lie algebra so(3,1 and its relatives. Finally, I suggest how the language of Cartan geometry provides a guiding principle for elegantly reformulating any 'gauge theory of geometry'.
Determining the minimum embedding dimension for state space ...
Indian Academy of Sciences (India)
the attractor is embedded in a lower dimension than the actual dimension of the system, there will be false neighbors within the recurrence threshold so that a ref- erence node gets connected to many nodes which are not real neighbors. Consequently, its clustering coeffi- cient C is affected. This is true for all nodes. Beyond.
Dimensions of design space: a decision-theoretic approach to optimal research design.
Conti, Stefano; Claxton, Karl
2009-01-01
Bayesian decision theory can be used not only to establish the optimal sample size and its allocation in a single clinical study but also to identify an optimal portfolio of research combining different types of study design. Within a single study, the highest societal payoff to proposed research is achieved when its sample sizes and allocation between available treatment options are chosen to maximize the expected net benefit of sampling (ENBS). Where a number of different types of study informing different parameters in the decision problem could be conducted, the simultaneous estimation of ENBS across all dimensions of the design space is required to identify the optimal sample sizes and allocations within such a research portfolio. This is illustrated through a simple example of a decision model of zanamivir for the treatment of influenza. The possible study designs include: 1) a single trial of all the parameters, 2) a clinical trial providing evidence only on clinical endpoints, 3) an epidemiological study of natural history of disease, and 4) a survey of quality of life. The possible combinations, samples sizes, and allocation between trial arms are evaluated over a range of cost-effectiveness thresholds. The computational challenges are addressed by implementing optimization algorithms to search the ENBS surface more efficiently over such large dimensions.
Pauli graphs when the Hilbert space dimension contains a square: Why the Dedekind psi function?
Energy Technology Data Exchange (ETDEWEB)
Planat, Michel, E-mail: michel.planat@femto-st.fr [Institut FEMTO-ST, CNRS, 32 Avenue de l' Observatoire, F-25044 Besancon (France)
2011-01-28
We study the commutation relations within the Pauli groups built on all decompositions of a given Hilbert space dimension q, containing a square, into its factors. Illustrative low-dimensional examples are the quartit (q = 4) and two-qubit (q = 2{sup 2}) systems, the octit (q = 8), qubit/quartit (q = 2 x 4) and three-qubit (q = 2{sup 3}) systems, and so on. In the single qudit case, e.g. q = 4, 8, 12, ... , one defines a bijection between the {sigma}(q) maximal commuting sets (with {sigma}[q) being the sum of divisors of q) of Pauli observables and the maximal submodules of the modular ring Z{sub q}{sup 2}, that arrange into the projective line P{sub 1}(Z{sub q}) and an independent set of size {sigma}(q) - {psi}(q) (with {psi}(q) being the Dedekind psi function). In the multiple qudit case, e.g. q = 2{sup 2}, 2{sup 3}, 3{sup 2}, ... , the Pauli graphs rely on symplectic polar spaces such as the generalized quadrangles GQ(2, 2) (if q = 2{sup 2}) and GQ(3, 3) (if q = 3{sup 2}). More precisely, in the dimension p{sup n} (p a prime) of the Hilbert space, the observables of the Pauli group (modulo the center) are seen as the elements of the 2n-dimensional vector space over the field F{sub p}. In this space, one makes use of the commutator to define a symplectic polar space W{sub 2n-1}(p) of cardinality {sigma}(p{sup 2n-1}) that encodes the maximal commuting sets of the Pauli group by its totally isotropic subspaces. Building blocks of W{sub 2n-1}(p) are punctured polar spaces (i.e. a observable and all maximum cliques passing to it are removed) of size given by the Dedekind psi function {psi}(p{sup 2n-1}). For multiple qudit mixtures (e.g. qubit/quartit, qubit/octit and so on), one finds multiple copies of polar spaces, punctured polar spaces, hypercube geometries and other intricate structures. Such structures play a role in the science of quantum information.
On the dimension of Chowla–Milnor space
Indian Academy of Sciences (India)
Abstract. In a recent work, Gun, Murty and Rath defined the Chowla–Milnor space and proved a non-trivial lower bound for these spaces. They also obtained a conditional improvement of this lower bound and noted that an unconditional improvement of their lower bound will lead to irrationality of ζ(k)/πk for odd positive ...
Male involvement: the missing dimension in promoting child spacing ...
African Journals Online (AJOL)
Greater sensitivity to information needs for men, the training of male medical staff in child spacing and orienting them to the concept could to such staff acting as counsellors for fellow men beside their other responsibilities. There is great scope in the country for involving men in child spacing and the number of agencies ...
Exact dimension estimation of interacting qubit systems assisted by a single quantum probe
Sone, Akira; Cappellaro, Paola
2017-12-01
Estimating the dimension of an Hilbert space is an important component of quantum system identification. In quantum technologies, the dimension of a quantum system (or its corresponding accessible Hilbert space) is an important resource, as larger dimensions determine, e.g., the performance of quantum computation protocols or the sensitivity of quantum sensors. Despite being a critical task in quantum system identification, estimating the Hilbert space dimension is experimentally challenging. While there have been proposals for various dimension witnesses capable of putting a lower bound on the dimension from measuring collective observables that encode correlations, in many practical scenarios, especially for multiqubit systems, the experimental control might not be able to engineer the required initialization, dynamics, and observables. Here we propose a more practical strategy that relies not on directly measuring an unknown multiqubit target system, but on the indirect interaction with a local quantum probe under the experimenter's control. Assuming only that the interaction model is given and the evolution correlates all the qubits with the probe, we combine a graph-theoretical approach and realization theory to demonstrate that the system dimension can be exactly estimated from the model order of the system. We further analyze the robustness in the presence of background noise of the proposed estimation method based on realization theory, finding that despite stringent constrains on the allowed noise level, exact dimension estimation can still be achieved.
The influence of abrasive body dimensions on single asperity wear
Woldman, M.; van der Heide, Emile; Tinga, Tiedo; Masen, Marc Arthur
2013-01-01
This work focuses on the relation between the properties of abrasive bodies and the wear they cause. By performing single asperity scratch tests to simulate abrasive wear, the wear process takes place in a controlled environment, allowing the properties of the abrasive body to be isolated and
Are perceived sensory dimensions a reliable tool for urban green space assessment and planning?
DEFF Research Database (Denmark)
Qiu, Ling; Nielsen, Anders Busse
2015-01-01
, nature, rich in species, space, prospect, refuge, social and culture. Using an onsite questionnaire distributed to green space visitors in Helsingborg, Sweden, this study is the first to examine the representation of the eight sensory dimensions in different types of urban green spaces as experienced...
Space dimension can prevent the blow-up of solutions for parabolic problems
Directory of Open Access Journals (Sweden)
Alkis S. Tersenov
2007-11-01
Full Text Available In the present paper, we investigate the preventive role of space dimension for semilinear parabolic problems. Conditions guaranteeing the absence of the blow-up of the solutions are formulated.
New dimensions for man. [human functions in future space missions
Louviere, A. J.
1978-01-01
The functions of man in space have been in a state of constant change since the first manned orbital flight. Initially, the onboard crewmen performed those tasks essential to piloting and navigating the spacecraft. The time devoted to these tasks has steadily decreased and the crewman's time is being allotted to functions other than orbital operations. The evolving functions include added orbital operational capabilities, experimentation, spacecraft maintenance, and fabrication of useful end items. The new functions will include routine utilization of the crewman to extend mission life, satellite retrieval and servicing, remote manipulator systems operations, and piloting of free-flying teleoperator systems. The most demanding tasks are anticipated to be associated with construction of large space structures. The projected changes will introduce innovative designs and revitalize the concepts for utilizing man in space.
Electrostatic energies of crystals in space of arbitrary dimension
International Nuclear Information System (INIS)
Takemoto, Hiroki; Tohsaki, Akihiro
2005-01-01
We present a new method to evaluate electrostatic energies under periodic boundary conditions. The lattice sum of Coulomb potentials is expressed through the elliptic Q function of the third kind. This enables us to evaluate electrostatic energies of ionic crystals very accurately and with very rapid convergence. In particular, we study the dimensionality of the electrostatic energies of NaCl-type and CsCl-type crystals, whose expressions are functions of the spatial dimension treated as a real number. Furthermore, the expressions we obtain are applicable to computational simulations using molecular dynamics and Monte Carlo methods. We generate random distributions of point charges under periodic boundary conditions, and we analyze the randomness and its anisotropy on the basis of potential distributions. (author)
Energy Technology Data Exchange (ETDEWEB)
Sansinena, Jose-Maria; Redondo, Antonio; Olazabal, Virginia; Hoffbauer, Mark A.
2017-09-12
A barrier structure for use in an electrochemical stochastic membrane sensor for single molecule detection. The sensor is based upon inorganic nanopores having electrically tunable dimensions. The inorganic nanopores are formed from inorganic materials and an electrically conductive polymer. Methods of making the barrier structure and sensing single molecules using the barrier structure are also described.
Sansinena, Jose-Maria [Los Alamos, NM; Redondo, Antonio [Los Alamos, NM; Olazabal, Virginia [Los Alamos, NM; Hoffbauer, Mark A [Los Alamos, NM; Akhadov, Elshan A [Los Alamos, NM
2009-12-29
A barrier structure for use in an electrochemical stochastic membrane sensor for single molecule detection. The sensor is based upon inorganic nanopores having electrically tunable dimensions. The inorganic nanopores are formed from inorganic materials and an electrically conductive polymer. Methods of making the barrier structure and sensing single molecules using the barrier structure are also described.
Energy Technology Data Exchange (ETDEWEB)
Sansinena, Jose-Maria; Redondo, Antonio; Olazabal, Virginia; Hoffbauer, Mark A.; Akhadov, Elshan A.
2017-10-31
A barrier structure for use in an electrochemical stochastic membrane sensor for single molecule detection. The sensor is based upon inorganic nanopores having electrically tunable dimensions. The inorganic nanopores are formed from inorganic materials and an electrically conductive polymer. Methods of making the barrier structure and sensing single molecules using the barrier structure are also described.
The Integrative Dimension of the Economic Globalization in European Space
Directory of Open Access Journals (Sweden)
Daniela Mariana Alexandrache
2010-06-01
Full Text Available We believe that globalization and its socio-economic implications of the world and world economic crisis is one of the most debated issues from several years. The publication "The Economist’’ named globalization as the most used word of the century. The most relevant dimension of globalization is the economy with the more dynamic factors: technological development, the hegemony of liberal conceptions (closely linked to the triumph of the ideology of market economy and explosive development of countries or regions. Economic globalization has manifested a series of visible effects such as: the emergence of new markets and foreign trade (interconnected at global level, the appearance of: transnational companies, multilateral agreements on trade, broadening the scope of WTO, transformation of multinational companies in transnational companies and the emergence of global economic markets. Regionally, we noticed that the trendof concentration of economic activity is more pronounced and advanced in the European continent. Expanding globalization in Europe was achieved because of the fall of communism, and the neoliberal reformation which took place in Western European countries. Events like the fall of the Berlin Wall, followed by the fall of communism eradicated many political, economic, religious or cultural barriers. There were born new relations between state and market, public and private. European Union is, in our view, a regional office ofglobalization, representing the best performing integrative system in the world (by creating free trade area, customs union, common market, the Economic and Monetary Union. In terms of the European Commission,European model is a third way towards globalization, a middle path between protectionism and uncontrolled economy. To understand why the EU is an advanced approximation of globalization, perhaps a regional model of globalization, we must first understand the link between globalization and regional
The Multigroup Neutron Diffusion Equations/1 Space Dimension
Energy Technology Data Exchange (ETDEWEB)
Linde, Sven
1960-06-15
A description is given of a program for the Ferranti Mercury computer which solves the one-dimensional multigroup diffusion equations in plane, cylindrical or spherical geometry, and also approximates automatically a two-dimensional solution by separating the space variables. In section A the method of calculation is outlined and the preparation of data for two group problems is described. The spatial separation of two-dimensional equations is considered in section B. Section C covers the multigroup equations. These parts are self contained and include all information required for the use of the program. Details of the numerical methods are given in section D. Three sample problems are solved in section E. Punching and operating instructions are given in an appendix.
The Multigroup Neutron Diffusion Equations/1 Space Dimension
International Nuclear Information System (INIS)
Linde, Sven
1960-06-01
A description is given of a program for the Ferranti Mercury computer which solves the one-dimensional multigroup diffusion equations in plane, cylindrical or spherical geometry, and also approximates automatically a two-dimensional solution by separating the space variables. In section A the method of calculation is outlined and the preparation of data for two group problems is described. The spatial separation of two-dimensional equations is considered in section B. Section C covers the multigroup equations. These parts are self contained and include all information required for the use of the program. Details of the numerical methods are given in section D. Three sample problems are solved in section E. Punching and operating instructions are given in an appendix
The Quantum Hydrodynamics System in Two Space Dimensions
Antonelli, Paolo
2011-09-16
In this paper we study global existence of weak solutions for the quantum hydrodynamics system in two-dimensional energy space. We do not require any additional regularity and/or smallness assumptions on the initial data. Our approach replaces the WKB formalism with a polar decomposition theory which is not limited by the presence of vacuum regions. In this way we set up a self consistent theory, based only on particle density and current density, which does not need to define velocity fields in the nodal regions. The mathematical techniques we use in this paper are based on uniform (with respect to the approximating parameter) Strichartz estimates and the local smoothing property. © 2011 Springer-Verlag.
International Nuclear Information System (INIS)
Nishioka, S.; Goto, I.; Hatayama, A.; Miyamoto, K.; Okuda, S.; Fukano, A.
2014-01-01
Our previous study by two dimension in real space and three dimension in velocity space-particle in cell model shows that the curvature of the plasma meniscus causes the beam halo in the negative ion sources. The negative ions extracted from the periphery of the meniscus are over-focused in the extractor due to the electrostatic lens effect, and consequently become the beam halo. The purpose of this study is to verify this mechanism with the full 3D model. It is shown that the above mechanism is essentially unchanged even in the 3D model, while the fraction of the beam halo is significantly reduced to 6%. This value reasonably agrees with the experimental result
Is overall similarity classification less effortful than single-dimension classification?
Wills, Andy J; Milton, Fraser; Longmore, Christopher A; Hester, Sarah; Robinson, Jo
2013-01-01
It is sometimes argued that the implementation of an overall similarity classification is less effortful than the implementation of a single-dimension classification. In the current article, we argue that the evidence securely in support of this view is limited, and report additional evidence in support of the opposite proposition--overall similarity classification is more effortful than single-dimension classification. Using a match-to-standards procedure, Experiments 1A, 1B and 2 demonstrate that concurrent load reduces the prevalence of overall similarity classification, and that this effect is robust to changes in the concurrent load task employed, the level of time pressure experienced, and the short-term memory requirements of the classification task. Experiment 3 demonstrates that participants who produced overall similarity classifications from the outset have larger working memory capacities than those who produced single-dimension classifications initially, and Experiment 4 demonstrates that instructions to respond meticulously increase the prevalence of overall similarity classification.
Picture this! grasping the dimensions of time and space
Carroll, Michael
2016-01-01
Astronomical concepts can be truly hard to comprehend, especially those of planetary sizes and distances from Earth and from each other. These concepts are made more comprehensible by the group of illustrations in this book, which put, in scale, side by side extraterrestrial objects with objects on Earth we can more easily relate to. For example, study the pictures of Earth floating above Jupiter’s Great Red Spot and the asteroid Itokawa resting beside Toronto’s CN Tower. These mind-bending images bring things better into perspective and will help you understand the size and scale of our Solar System. In later chapters, you will be told how close the visionaries of the past came to guessing what today’s explorers would find. Astronomer/painter Lucien Rudaux’s masterpieces of Mars dust storms anticipated Viking and Mars rover images by nearly a century. Space artist Ludek Pesek envisioned astronauts setting up camp on the lunar surface in scenes hauntingly similar to photos taken by Apollo a...
Arbitrary Dimension Convection-Diffusion Schemes for Space-Time Discretizations
Energy Technology Data Exchange (ETDEWEB)
Bank, Randolph E. [Univ. of California, San Diego, CA (United States); Vassilevski, Panayot S. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Zikatanov, Ludmil T. [Bulgarian Academy of Sciences, Sofia (Bulgaria)
2016-01-20
This note proposes embedding a time dependent PDE into a convection-diffusion type PDE (in one space dimension higher) with singularity, for which two discretization schemes, the classical streamline-diffusion and the EAFE (edge average finite element) one, are investigated in terms of stability and error analysis. The EAFE scheme, in particular, is extended to be arbitrary order which is of interest on its own. Numerical results, in combined space-time domain demonstrate the feasibility of the proposed approach.
Analytic smoothing effect for the cubic hyperbolic Schrodinger equation in two space dimensions
Directory of Open Access Journals (Sweden)
Gaku Hoshino
2016-01-01
Full Text Available We study the Cauchy problem for the cubic hyperbolic Schrodinger equation in two space dimensions. We prove existence of analytic global solutions for sufficiently small and exponential decaying data. The method of proof depends on the generalized Leibniz rule for the generator of pseudo-conformal transform acting on pseudo-conformally invariant nonlinearity.
Energy-spectrum against topological charge in a nonlinear model in three space-dimensions
International Nuclear Information System (INIS)
Kundu, A.
1981-08-01
A nonlinear field model in three space-dimensions with nontrivial Hopf invariant is studied in an intermediate S 3 -manifold. Energy-spectrum of the system for different values of topological charge is calculated numerically, which with fair accuracy coincides with E 1 n(n+1)/2 where n=topological charge. (author)
Study of FCNC-mediated rare Bs decays in a single universal extra dimension scenario
International Nuclear Information System (INIS)
Mohanta, R.; Giri, A. K.
2007-01-01
We study the rare semileptonic and radiative leptonic B s decays in the universal extra dimension model. In this scenario, with a single extra dimension, there exists only one new parameter beyond those of the standard model, which is the inverse of the compactification radius R. We find that with the additional contributions due to the Kaluza-Klein (KK) modes the branching ratios of the rare B s decays are enhanced from their corresponding standard model values and the zero point of the forward-backward asymmetries are shifted towards the left
Search for Extra dimensions in a single-jet and missing energy channel at CMS experiment
Benucci, Leonardo
2010-01-01
A possible solution to the hierarchy problem is the presence of extra spatial dimensions beyond the three ones which are known from our everyday experience. The phenomenological ADD model of large extra-dimensions predicts a missing transverse energy plus a single-jet signature. This contribution addresses the sensitivity of the CMS detector at the LHC pp collider to parameters of this model, focusing on the conditions expected for second half of 2010 running (sqrt(s) = 10 TeV, O(100) pb-1). It is shown that a significant improvement of the existing limits can be obtained in such an early stage.
Life-space mobility and dimensions of depressive symptoms among community-dwelling older adults.
Polku, Hannele; Mikkola, Tuija M; Portegijs, Erja; Rantakokko, Merja; Kokko, Katja; Kauppinen, Markku; Rantanen, Taina; Viljanen, Anne
2015-01-01
To examine the association between life-space mobility and different dimensions of depressive symptoms among older community-dwelling people. Cross-sectional analyses of baseline data of the 'Life-Space Mobility in Old Age' cohort study were carried out. The participants were community-dwelling women and men aged 75-90 years (N = 848). Data were gathered via structured interviews in participants' home. Life-space mobility (the University of Alabama at Birmingham (UAB) Life-Space Assessment - questionnaire) and depressive symptoms (Centre for Epidemiological Studies Depression Scale, CES-D) were assessed. Other factors examined included sociodemographic factors, difficulties walking 500 m, number of chronic diseases and the sense of autonomy in participation outdoors (subscale of Impact on Participation and Autonomy questionnaire). Poorer life-space mobility was associated with higher prevalence of different dimensions of depressive symptoms. The associations were partially mediated through walking difficulties, health and the sense of autonomy in participation outdoor activities. Poorer life-space mobility interrelates with higher probability for depressive symptoms, thus compromising older adults' mental wellbeing. A focus on older adults' life-space mobility may assist early identification of persons, who have elevated risk for depressive symptoms. The association between life-space mobility and depressive symptoms should be studied further utilizing longitudinal study designs to examine temporality and potential causality.
Categorical Dimensions of Human Odor Descriptor Space Revealed by Non-Negative Matrix Factorization
Castro, Jason B.; Ramanathan, Arvind; Chennubhotla, Chakra S.
2013-01-01
In contrast to most other sensory modalities, the basic perceptual dimensions of olfaction remain unclear. Here, we use non-negative matrix factorization (NMF) – a dimensionality reduction technique – to uncover structure in a panel of odor profiles, with each odor defined as a point in multi-dimensional descriptor space. The properties of NMF are favorable for the analysis of such lexical and perceptual data, and lead to a high-dimensional account of odor space. We further provide evidence that odor dimensions apply categorically. That is, odor space is not occupied homogenously, but rather in a discrete and intrinsically clustered manner. We discuss the potential implications of these results for the neural coding of odors, as well as for developing classifiers on larger datasets that may be useful for predicting perceptual qualities from chemical structures. PMID:24058466
Jittoh, Toshifumi; Koike, Masafumi; Nomura, Takaaki; Sato, Joe; Shimomura, Takashi
2009-03-01
We investigate ten-dimensional gauge theories whose extra six-dimensional space is a compact coset space, S/R, and whose gauge group is a direct product of two Lie groups. We list candidates of the gauge group and embeddings of R into them. After dimensional reduction of the coset space, we find fermion and scalar representations of GGUT×U(1) with GGUT=SU(5), SO(10) and E6, which accommodate all of the standard model particles. We also discuss possibilities to generate distinct Yukawa couplings among the generations using representations with different dimensions for GGUT=SO(10) and E6 models.
Directory of Open Access Journals (Sweden)
Kimber Haddix McKay
2010-02-01
Full Text Available This paper analyzes the socio-cultural dimensions of obstacles facing solar photovoltaic projects in two villages in rural Nepal. The study was conducted in Humla District, Nepal, one of the most remote and impoverished regions of the country. There are no roads in the district, homes lack running water and villagers’ health suffers from high levels of indoor air pollution from open cooking/heating fires and the smoky torches traditionally burned for light. The introduction of solar energy is important to these villagers, as it removes one major source of indoor air pollution from homes and provides brighter light than the traditional torches. Solar energy is preferable in many villages in the region due to the lack of suitable streams or rivers for micro-hydroelectric projects. In the villages under study in this paper, in-home solar electricity is a novel and recent innovation, and was installed within the last three years in two different geo-spatial styles, depending upon the configuration of homes in the village. In some villages, houses are grouped together, while in others households are widely dispersed. In the former, solar photovoltaic systems were installed in a “cluster” fashion with multiple homes utilizing power from a central battery store under the control of the householder storing the battery bank. In villages with widely spaced households, a single home system was used so that each home had a separate solar photovoltaic array, wiring system and battery bank. It became clear that the cluster system was the sensible choice due to the geographic layout of certain villages, but this put people into management groups that did not always work well due to caste or other differences. This paper describes the two systems and their management and usage costs and benefits from the perspective of the villagers themselves.
O(n) relations for coupling constants and space-time dimensions in dual models
Frampton, Paul H
1972-01-01
It is proposed that certain daughter trajectories arise as a consequence of a higher underlying O(n) symmetry, with n>3. This suggestion is motivated by the dual resonance model, where such a pattern arises naturally from the existence of a critical space-time dimension. This is easily confirmed in the model (and provides a simple test for what is the critical dimension) by considering the amplitudes for spinless particles. The results of pi N phase shift analysis are discussed to give a speculative phenomenological estimate of the appropriate higher symmetry. (16 refs).
Qubits and oriented matroids in four time and four space dimensions
Energy Technology Data Exchange (ETDEWEB)
Nieto, J.A., E-mail: janieto1@asu.edu [Facultad de Ciencias Fisico-Matematicas de la Universidad Autonoma de Sinaloa, 80010, Culiacan Sinaloa (Mexico); Mathematical, Computational and Modeling Sciences Center, Arizona State University, PO Box 871904, Tempe, AZ 85287 (United States)
2013-01-29
We establish a connection between 4-rebits (real qubits) and the Nambu-Goto action with target 'spacetime' of four time and four space dimensions ((4+4)-dimensions). We motivate the subject with three observations. The first one is that a 4-rebit contains exactly the same number of degree of freedom as a complex 3-qubit and therefore 4-rebits are special in the sense of division algebras. Secondly, the (4+4)-dimensions can be splitted as (4+4)=(3+1)+(1+3) and therefore they are connected with an ordinary (1+3)-spacetime and with changed signature (3+1)-spacetime. Finally, we show how geometric aspects of 4-rebits can be related to the chirotope concept of oriented matroid theory.
Qubits and oriented matroids in four time and four space dimensions
International Nuclear Information System (INIS)
Nieto, J.A.
2013-01-01
We establish a connection between 4-rebits (real qubits) and the Nambu–Goto action with target ‘spacetime’ of four time and four space dimensions ((4+4)-dimensions). We motivate the subject with three observations. The first one is that a 4-rebit contains exactly the same number of degree of freedom as a complex 3-qubit and therefore 4-rebits are special in the sense of division algebras. Secondly, the (4+4)-dimensions can be splitted as (4+4)=(3+1)+(1+3) and therefore they are connected with an ordinary (1+3)-spacetime and with changed signature (3+1)-spacetime. Finally, we show how geometric aspects of 4-rebits can be related to the chirotope concept of oriented matroid theory.
Tumor growth in the space-time with temporal fractal dimension
International Nuclear Information System (INIS)
Molski, Marcin; Konarski, Jerzy
2008-01-01
An improvement of the Waliszewski and Konarski approach [Waliszewski P, Konarski J. The Gompertzian curve reveals fractal properties of tumor growth. Chaos, Solitons and Fractals 2003;16:665-74] to determination of the time-dependent temporal fractal dimension b t (t) and the scaling factor a t (t) for the tumor formation in the fractal space-time is presented. The analytical formulae describing the time-dependence of b t (t) and a t (t), which take into account appropriate boundary conditions for t → 0 and t → ∞, are derived. Their validity is tested on the experimental growth curve obtained by Laird for the Flexner-Jobling rat's tumor. A hypothesis is formulated that tumorigenesis has a lot in common with the neuronal differentiation and synapse formation. These processes are qualitatively described by the same Gompertz function of growth and take place in the fractal space-time whose mean temporal fractal dimension is lost during progression
Dimension elevation in Müntz spaces: A new emergence of the Müntz condition
Ait-Haddou, Rachid
2014-05-01
We show that the limiting polygon generated by the dimension elevation algorithm with respect to the Müntz space span(1,tr1,tr2,trm,. . .), with 0 < r1 < r2 < ⋯ < r m < ⋯ and lim n →∞r n = ∞, over an interval [a, b] ⊂ ] 0, ∞ [ converges to the underlying Chebyshev-Bézier curve if and only if the Müntz condition ∑i=1∞1ri=∞ is satisfied. The surprising emergence of the Müntz condition in the problem raises the question of a possible connection between the density questions of nested Chebyshev spaces and the convergence of the corresponding dimension elevation algorithms. The question of convergence with no condition of monotonicity or positivity on the pairwise distinct real numbers r i remains an open problem. © 2014 Elsevier Inc.
Study of Extra Space Dimensions in Vector Boson Pair Production at LEP
Mele, Salvatore
2000-01-01
Recent theoretical scenarios propose that quantum gravity effects may manifest at LEP energies by means of gravitons that couple to Standard Model particles and propagate into extra space dimensions. These predictions are checked against the most recent experimental results on photon, W and Z pair production. No deviations from the Standard Model expectations are found and limits of the order of 1\\,TeV on the scale of these models are set.
Exact Green's function of the reversible ABCD reaction in two space dimensions
Prüstel, Thorsten; Meier-Schellersheim, Martin
2013-01-01
We derive an exact expression for the Green's functions in the time domain of the reversible diffusion-influenced ABCD reaction $A+B\\leftrightarrow C+D$ in two space dimensions. Furthermore, we calculate the corresponding survival and reaction probabilities. The obtained expressions should prove useful for the study of reversible membrane-bound reactions in cell biology and can serve as a useful ingredient of enhanced stochastic particle-based simulation algorithms.
Reality and dimension of space and the complexity of quantum mechanics
International Nuclear Information System (INIS)
Mirman, R.
1988-01-01
The dimension (and signature) of space is a result of distances being real numbers and quantum mechanical state functions being complex ones; it is an inescapable consequence of quantum mechanics and group theory. So nonrelativistic quantum mechanics cannot be complete (it requires ad hoc additional assumptions) and consistent (nor can classical physics), leading to relativity, quantum mechanics, and field theory. Implications of the constraints of consistency and physical reasonableness and of group theory for the structure of these theories are considered. It appears that there are simple, perhaps unavoidable reasons for the laws of physics, the nature of the world they describe, and the space in which they act
FCNC Bs and Λb transitions: Standard model versus a single universal extra dimension scenario
International Nuclear Information System (INIS)
Colangelo, P.; De Fazio, F.; Ferrandes, R.; Pham, T. N.
2008-01-01
We study the flavor changing neutral current B s →φγ, φνν and Λ b →Λγ, Λνν transitions in the standard model and in a scenario with a single universal extra dimension. In particular, we focus on the present knowledge of the hadronic uncertainties and on possible improvements. We discuss how the measurements of these modes can be used to constrain the new parameter involved in the extra-dimensional scenario, the radius R of the extra dimension, completing the information available from B-factories. The rates of these b→s induced decays are within the reach of new experiments, such as LHCb.
Jin Shi
2003-01-01
Chemical vapor infiltration (CVI) process is an important technology to fabricate ceramic matrix composites (CMC's). In this paper, a three-dimension numerical model is presented to describe pore microstructure evolution during the CVI process. We extend the two-dimension model proposed in [S. Jin, X.L. Wang, T.L. Starr, J. Mater. Res. 14 (1999) 3829; S. Jin. X.L. Wang, T.L. Starr, X.F. Chen, J. Comp. Phys. 162 (2000) 467], where the fiber surface is modeled as an evolving interface, to the three space dimension. The 3D method keeps all the virtue of the 2D model: robust numerical capturing of topological changes of the interface such as the merging, and fast detection of the inaccessible pores. For models in the kinetic limit, where the moving speed of the interface is constant, some numerical examples are presented to show that this three-dimension model will effectively track the change of porosity, close-off time, location and shape of all pores.
Categorical dimensions of human odor descriptor space revealed by non-negative matrix factorization
Energy Technology Data Exchange (ETDEWEB)
Chennubhotla, Chakra [University of Pittsburgh School of Medicine, Pittsburgh PA; Castro, Jason [Bates College
2013-01-01
In contrast to most other sensory modalities, the basic perceptual dimensions of olfaction remain un- clear. Here, we use non-negative matrix factorization (NMF) - a dimensionality reduction technique - to uncover structure in a panel of odor profiles, with each odor defined as a point in multi-dimensional descriptor space. The properties of NMF are favorable for the analysis of such lexical and perceptual data, and lead to a high-dimensional account of odor space. We further provide evidence that odor di- mensions apply categorically. That is, odor space is not occupied homogenously, but rather in a discrete and intrinsically clustered manner. We discuss the potential implications of these results for the neural coding of odors, as well as for developing classifiers on larger datasets that may be useful for predicting perceptual qualities from chemical structures.
Shape component analysis: structure-preserving dimension reduction on biological shape spaces.
Lee, Hao-Chih; Liao, Tao; Zhang, Yongjie Jessica; Yang, Ge
2016-03-01
Quantitative shape analysis is required by a wide range of biological studies across diverse scales, ranging from molecules to cells and organisms. In particular, high-throughput and systems-level studies of biological structures and functions have started to produce large volumes of complex high-dimensional shape data. Analysis and understanding of high-dimensional biological shape data require dimension-reduction techniques. We have developed a technique for non-linear dimension reduction of 2D and 3D biological shape representations on their Riemannian spaces. A key feature of this technique is that it preserves distances between different shapes in an embedded low-dimensional shape space. We demonstrate an application of this technique by combining it with non-linear mean-shift clustering on the Riemannian spaces for unsupervised clustering of shapes of cellular organelles and proteins. Source code and data for reproducing results of this article are freely available at https://github.com/ccdlcmu/shape_component_analysis_Matlab The implementation was made in MATLAB and supported on MS Windows, Linux and Mac OS. geyang@andrew.cmu.edu. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.
Variability of ischiofemoral space dimensions with changes in hip flexion: an MRI study
Energy Technology Data Exchange (ETDEWEB)
Johnson, Adam C.; Howe, Benjamin M. [Mayo Clinic College of Medicine, Department of Radiology, Rochester, MN (United States); Hollman, John H.; Finnoff, Jonathan T. [Mayo Clinic College of Medicine, Department of Physical Medicine and Rehabilitation, Rochester, MN (United States)
2017-01-15
The primary aim of this study was to determine if ischiofemoral space (IFS) dimensions vary with changes in hip flexion as a result of placing a bolster behind the knees during magnetic resonance imaging (MRI). A secondary aim was to determine if IFS dimensions vary between supine and prone hip neutral positions. The study employed a prospective design. Sports medicine center within a tertiary care institution. Five male and five female adult subjects (age mean = 29.2, range = 23-35; body mass index [BMI] mean = 23.5, range = 19.5-26.6) were recruited to participate in the study. An axial, T1-weighted MRI sequence of the pelvis was obtained of each subject in a supine position with their hips in neutral and flexed positions, and in a prone position with their hips in neutral position. Supine hip flexion was induced by placing a standard, 9-cm-diameter MRI knee bolster under the subject's knees. The order of image acquisition (supine hip neutral, supine hip flexed, prone hip neutral) was randomized. The IFS dimensions were then measured on a separate workstation. The investigator performing the IFS measurements was blinded to the subject position for each image. The main outcome measurements were the IFS dimensions acquired with MRI. The mean IFS dimensions in the prone position were 28.25 mm (SD 5.91 mm, standard error mean 1.32 mm). In the supine hip neutral position, the IFS dimensions were 25.1 (SD 5.6) mm. The mean difference between the two positions of 3.15 (3.6) mm was statistically significant (95 % CI of the difference = 1.4 to 4.8 mm, t{sub 19} = 3.911, p =.001). The mean IFS dimensions in the hip flexed position were 36.9 (SD 5.7) mm. The mean difference between the two supine positions of 11.8 (4.1) mm was statistically significant (95 % CI of the difference = 9.9 to 13.7 mm, t{sub 19} = 12.716, p <.001). Our findings demonstrate that the IFS measurements obtained with MRI are dependent upon patient positioning with respect to hip flexion and
International Nuclear Information System (INIS)
Alvarez-Estrada, R.F.
1979-01-01
A comprehensive review of the inverse scattering solution of certain non-linear evolution equations of physical interest in one space dimension is presented. We explain in some detail the interrelated techniques which allow to linearize exactly the following equations: (1) the Korteweg and de Vries equation; (2) the non-linear Schrodinger equation; (3) the modified Korteweg and de Vries equation; (4) the Sine-Gordon equation. We concentrate in discussing the pairs of linear operators which accomplish such an exact linearization and the solution of the associated initial value problem. The application of the method to other non-linear evolution equations is reviewed very briefly
Indian Academy of Sciences (India)
First page Back Continue Last page Overview Graphics. Extra dimensions: There is another way that particles arise from string theory. This has to do with extra space dimensions. String theory is consistent in 9 spatial dimensions. But we live in 3 dimensions. So the other 6 must be compact. Notes:
Real-space mean-field theory of a spin-1 Bose gas in synthetic dimensions
Hurst, Hilary M.; Wilson, Justin H.; Pixley, J. H.; Spielman, I. B.; Natu, Stefan S.
2016-12-01
The internal degrees of freedom provided by ultracold atoms provide a route for realizing higher dimensional physics in systems with limited spatial dimensions. Nonspatial degrees of freedom in these systems are dubbed "synthetic dimensions." This connection is useful from an experimental standpoint but complicated by the fact that interactions alter the condensate ground state. Here we use the Gross-Pitaevskii equation to study the ground-state properties of a spin-1 Bose gas under the combined influence of an optical lattice, spatially varying spin-orbit coupling, and interactions at the mean-field level. The associated phases depend on the sign of the spin-dependent interaction parameter and the strength of the spin-orbit field. We find "charge"- and spin-density-wave phases which are directly related to helical spin order in real space and affect the behavior of edge currents in the synthetic dimension. We determine the resulting phase diagram as a function of the spin-orbit coupling and spin-dependent interaction strength, considering both attractive (ferromagnetic) and repulsive (polar) spin-dependent interactions, and we provide a direct comparison of our results with the noninteracting case. Our findings are applicable to current and future experiments, specifically with 87Rb, 7Li, 41K, and 23Na.
Color Confinement and Spatial Dimensions in the Complex-Sedenion Space
Directory of Open Access Journals (Sweden)
Zi-Hua Weng
2017-01-01
Full Text Available The paper aims to apply the complex-sedenions to explore the wave functions and field equations of non-Abelian gauge fields, considering the spatial dimensions of a unit vector as the color degrees of freedom in the complex-quaternion wave functions, exploring the physical properties of the color confinement essentially. J. C. Maxwell was the first to employ the quaternions to study the electromagnetic fields. His method inspires subsequent scholars to introduce the quaternions, octonions, and sedenions to research the electromagnetic field, gravitational field, and nuclear field. The application of complex-sedenions is capable of depicting not only the field equations of classical mechanics, but also the field equations of quantum mechanics. The latter can be degenerated into the Dirac equation and Yang-Mills equation. In contrast to the complex-number wave function, the complex-quaternion wave function possesses three new degrees of freedom, that is, three color degrees of freedom. One complex-quaternion wave function is equivalent to three complex-number wave functions. It means that the three spatial dimensions of unit vector in the complex-quaternion wave function can be considered as the “three colors”; naturally the color confinement will be effective. In other words, in the complex-quaternion space, the “three colors” are only the spatial dimensions, rather than any property of physical substance.
Scalable implicit methods for reaction-diffusion equations in two and three space dimensions
Energy Technology Data Exchange (ETDEWEB)
Veronese, S.V.; Othmer, H.G. [Univ. of Utah, Salt Lake City, UT (United States)
1996-12-31
This paper describes the implementation of a solver for systems of semi-linear parabolic partial differential equations in two and three space dimensions. The solver is based on a parallel implementation of a non-linear Alternating Direction Implicit (ADI) scheme which uses a Cartesian grid in space and an implicit time-stepping algorithm. Various reordering strategies for the linearized equations are used to reduce the stride and improve the overall effectiveness of the parallel implementation. We have successfully used this solver for large-scale reaction-diffusion problems in computational biology and medicine in which the desired solution is a traveling wave that may contain rapid transitions. A number of examples that illustrate the efficiency and accuracy of the method are given here; the theoretical analysis will be presented.
A discrete classical space-time could require 6 extra-dimensions
Guillemant, Philippe; Medale, Marc; Abid, Cherifa
2018-01-01
We consider a discrete space-time in which conservation laws are computed in such a way that the density of information is kept bounded. We use a 2D billiard as a toy model to compute the uncertainty propagation in ball positions after every shock and the corresponding loss of phase information. Our main result is the computation of a critical time step above which billiard calculations are no longer deterministic, meaning that a multiverse of distinct billiard histories begins to appear, caused by the lack of information. Then, we highlight unexpected properties of this critical time step and the subsequent exponential evolution of the number of histories with time, to observe that after certain duration all billiard states could become possible final states, independent of initial conditions. We conclude that if our space-time is really a discrete one, one would need to introduce extra-dimensions in order to provide supplementary constraints that specify which history should be played.
Space-time supersymmetry of extended fermionic strings in 2 + 2 dimensions
International Nuclear Information System (INIS)
Ketov, S.V.
1993-04-01
The N = 2 fermionic string theory is revisited in light of its recently proposed equivalence to the non-compact N = 4 fermionic string model. The issues of space-time Lorentz covariance and supersymmetry for the BRST quantized N = 2 strings living in uncompactified 2 + 2 dimensions are discussed. The equivalent local quantum supersymmetric field theory appears to be the most transparent way to represent the space-time symmetries of the extended fermionic strings and their interactions. Our considerations support the Siegel's ideas about the presence of SO(2,2) Lorentz symmetry as well as at least two self-dual space-time supersymmetries in the theory of the N = 2(4) fermionic strings, though we do not have a compelling reason to argue about the necessity of the maximal space-time supersymmetry. The world-sheet arguments about the absence of all string massive modes in the physical spectrum, and the vanishing of all string-loop amplitudes in the Polyakov approach, are given on the basis of general consistency of the theory. (orig.)
Rodriguez, Ricardo; Lewis, Winston G.
2014-07-01
Adequately identifying and managing hazards at the workplace can be a tedious task which extends into the realm of uncertainty, probability and prediction models in order to fully comprehend the nature of the hazard. As such, organizations cannot be blamed for knowledge gaps in the training of personnel they contract to ensure a safe and healthy work environment, especially where there are latent hazards. Electromagnetic wave propagation at frequencies in the SAR (specific absorption rate) region is a special concern to authorities involved in setting RF (radiofrequency) and microwave exposure guidelines. Despite that there is no conclusive evidence to suggest that non-ionizing electromagnetic radiation causes adverse health effects other than thermal, no effort should be lost to ensure that workers and the public at large are adequately protected from unnecessary exposure to radiation. Standards however set exposure limits for free space, plane wave propagation but fall short in compiling information on intensities of these waves after they undergo reflection and diffraction from wall surfaces. Waveguide technology has managed to constrain microwaves to remain within set boundaries, with fixed frequencies that force the waves to behave differently to if they were moving in free space. This technology has offered the ability to transport more energy for communication purposes other than transmission lines. The size of a waveguide may be to the order of a few centimetres and can guide RF of wavelengths of the order of centimetres also but what if spaces of larger dimensions are capable of being waveguides and can guide waves of larger wavelengths such as those that correspond to frequencies between 30MHz to 300MHz? Such RF waves belong to the SAR region of the spectrum where strict exposure limits are set for health and safety protection since a standing man acts as a dipole antenna for this radiation and can absorb maximum energy from propagating RF waves. This
International Nuclear Information System (INIS)
Rodriguez, Ricardo; Lewis, Winston G
2014-01-01
Adequately identifying and managing hazards at the workplace can be a tedious task which extends into the realm of uncertainty, probability and prediction models in order to fully comprehend the nature of the hazard. As such, organizations cannot be blamed for knowledge gaps in the training of personnel they contract to ensure a safe and healthy work environment, especially where there are latent hazards. Electromagnetic wave propagation at frequencies in the SAR (specific absorption rate) region is a special concern to authorities involved in setting RF (radiofrequency) and microwave exposure guidelines. Despite that there is no conclusive evidence to suggest that non-ionizing electromagnetic radiation causes adverse health effects other than thermal, no effort should be lost to ensure that workers and the public at large are adequately protected from unnecessary exposure to radiation. Standards however set exposure limits for free space, plane wave propagation but fall short in compiling information on intensities of these waves after they undergo reflection and diffraction from wall surfaces. Waveguide technology has managed to constrain microwaves to remain within set boundaries, with fixed frequencies that force the waves to behave differently to if they were moving in free space. This technology has offered the ability to transport more energy for communication purposes other than transmission lines. The size of a waveguide may be to the order of a few centimetres and can guide RF of wavelengths of the order of centimetres also but what if spaces of larger dimensions are capable of being waveguides and can guide waves of larger wavelengths such as those that correspond to frequencies between 30MHz to 300MHz? Such RF waves belong to the SAR region of the spectrum where strict exposure limits are set for health and safety protection since a standing man acts as a dipole antenna for this radiation and can absorb maximum energy from propagating RF waves. This
Skeleton series and multivaluedness of the self-energy functional in zero space-time dimensions
Rossi, Riccardo; Werner, Félix
2015-12-01
Recently, Kozik, Ferrero and Georges discovered numerically that for a family of fundamental models of interacting fermions, the self-energy {{Σ }}[G] is a multi-valued functional of the fully dressed single-particle propagator G, and that the skeleton diagrammatic series {{{Σ }}}{{bold}}[G] converges to the wrong branch above a critical interaction strength. We consider the zero space-time dimensional case, where the same mathematical phenomena appear from elementary algebra. We also find a similar phenomenology for the fully bold formalism built on the fully dressed single-particle propagator and pair propagator.
Gerencsér, Máté; Jentzen, Arnulf; Salimova, Diyora
2017-11-01
In a recent article (Jentzen et al. 2016 Commun. Math. Sci. 14 , 1477-1500 (doi:10.4310/CMS.2016.v14.n6.a1)), it has been established that, for every arbitrarily slow convergence speed and every natural number d ∈{4,5,…}, there exist d -dimensional stochastic differential equations with infinitely often differentiable and globally bounded coefficients such that no approximation method based on finitely many observations of the driving Brownian motion can converge in absolute mean to the solution faster than the given speed of convergence. In this paper, we strengthen the above result by proving that this slow convergence phenomenon also arises in two ( d =2) and three ( d =3) space dimensions.
Connection between Feynman integrals having different values of the space-time dimension
International Nuclear Information System (INIS)
Tarasov, O.V.
1996-05-01
A systematic algorithm for obtaining recurrence relations for dimensionally regularized Feynman integrals w.r.t. the space-time dimension d is proposed. The relation between d and d-2 dimensional integrals is given in terms of a differential operator for which an explicit formula can be obtained for each Feynman diagram. We show how the method works for one-, two- and three-loop integrals. The new recurrence relations w.r.t. d are complementary to the recurrence relations which derive from the method of integration by parts. We find that the problem of the irreducible numerators in Feynman integrals can be naturally solved in the framework of the proposed generalized recurrence relations. (orig.)
Forcella, Luigi; Visciglia, Nicola
2018-01-01
We consider a class of 1D NLS perturbed with a steplike potential. We prove that the nonlinear solutions satisfy the double scattering channels in the energy space. The proof is based on concentration-compactness/rigidity method. We prove moreover that in dimension higher than one, classical scattering holds if the potential is periodic in all but one dimension and is steplike and repulsive in the remaining one.
Spaces of Play: The Spatial Dimensions of Underground Club Culture and Locating the Subjunctive
Directory of Open Access Journals (Sweden)
Alice O'Grady
2012-05-01
Full Text Available Normal 0 0 1 153 875 7 1 1074 11.1539 0 0 0 Normal 0 false false false EN-AU JA X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman";} This article examines the interrelated concepts of space, play and performativity in relation to the underground club scene in the UK. Grounded in the discipline of performance studies, this article uses the lens of play to identify how the spatial characteristics of underground dance culture provide a fertile terrain for performative acts of collectivity and expression. Resonating with previous EDMC scholarship that invokes concepts of liminality and the social dimensions of “spontaneous communitas”, the physical and psychical dimensions of play will be considered. Applying Turner’s work on subjunctivity (1982 and Jill Dolan’s concept of “utopian performatives” (2005 in relation to the psytrance scene, the article positions the underground party as a playful arena, a spatial construct that offers a context for moments of individual and collective transformation that are expressed and experienced performatively.
Pelagic habitat visualization: the need for a third (and fourth) dimension: HabitatSpace
Beegle-Krause, C; Vance, Tiffany; Reusser, Debbie; Stuebe, David; Howlett, Eoin
2009-01-01
Habitat in open water is not simply a 2-D to 2.5-D surface such as the ocean bottom or the air-water interface. Rather, pelagic habitat is a 3-D volume of water that can change over time, leading us to the term habitat space. Visualization and analysis in 2-D is well supported with GIS tools, but a new tool was needed for visualization and analysis in four dimensions. Observational data (cruise profiles (xo, yo, z, to)), numerical circulation model fields (x,y,z,t), and trajectories (larval fish, 4-D line) need to be merged together in a meaningful way for visualization and analysis. As a first step toward this new framework, UNIDATA’s Integrated Data Viewer (IDV) has been used to create a set of tools for habitat analysis in 4-D. IDV was designed for 3-D+time geospatial data in the meteorological community. NetCDF JavaTM libraries allow the tool to read many file formats including remotely located data (e.g. data available via OPeNDAP ). With this project, IDV has been adapted for use in delineating habitat space for multiple fish species in the ocean. The ability to define and visualize boundaries of a water mass, which meets specific biologically relevant criteria (e.g., volume, connectedness, and inter-annual variability) based on model results and observational data, will allow managers to investigate the survival of individual year classes of commercially important fisheries. Better understanding of the survival of these year classes will lead to improved forecasting of fisheries recruitment.
The large dimension limit of a small black hole instability in anti-de Sitter space
Herzog, Christopher P.; Kim, Youngshin
2018-02-01
We study the dynamics of a black hole in an asymptotically AdS d × S d space-time in the limit of a large number of dimensions, d → ∞. Such a black hole is known to become dynamically unstable below a critical radius. We derive the dispersion relation for the quasinormal mode that governs this instability in an expansion in 1 /d. We also provide a full nonlinear analysis of the instability at leading order in 1 /d. We find solutions that resemble the lumpy black spots and black belts previously constructed numerically for small d, breaking the SO( d + 1) rotational symmetry of the sphere down to SO( d). We are also able to follow the time evolution of the instability. Due possibly to limitations in our analysis, our time dependent simulations do not settle down to stationary solutions. This work has relevance for strongly interacting gauge theories; through the AdS/CFT correspondence, the special case d = 5 corresponds to maximally supersymmetric Yang-Mills theory on a spatial S 3 in the microcanonical ensemble and in a strong coupling and large number of colors limit.
Directory of Open Access Journals (Sweden)
Marianna Forleo
2012-10-01
Full Text Available In the last centuries, the relationship between science and literature has had numerous manifestations. One of the most interesting aspects was the use of the scientific language in utopian Victorian texts. The analysis of Flatland, a Romance of Many Dimensions by Edwin Abbott is a starting point for the description of utopian cities, where literature uses science as a technical tool for the explanation of the world. Science becomes a clear metaphor of a rational organization and strategic element for spreading “subliminal” messages. The combination between utopia and science can seem exclusively a theoretical and philosophical relationship, but in reality, it is only a tool to approach the utopian practice. The main feature of utopian texts is its criticism of society, which is made possible only if hidden in metaphorical terms. Indeed, Flatland, as many other mathematical utopias, presents itself as a multidimensional text. The use of geometric structures for the description of utopian spaces allows several interpretations. Science and literature intertwine throughout the text but nevertheless keep their own distinct features.
Exact de Rham Sequences of Spaces Defined on Macro-elements in Two and Three Spatial Dimensions
Energy Technology Data Exchange (ETDEWEB)
Pasciak, J; Vassilevski, P
2007-07-23
This paper proposes new finite element spaces that can be constructed for agglomerates of standard elements that have certain regular structure. The main requirement is that the agglomerates share faces that have closed boundaries composed of 1-d edges. The spaces resulting from the agglomerated elements are subspaces of the original de Rham sequence of H{sup 1}-conforming, H(curl) conforming, H(div) conforming and piecewise constant spaces associated with an unstructured 'fine' mesh. The procedure can be recursively applied so that a sequence of nested de Rham complexes can be constructed. As an illustration we generate coarser spaces from the sequence corresponding to the lowest order Nedelec spaces, lowest order Raviart-Thomas spaces, and for piecewise linear H{sup 1}-conforming spaces, all in three-dimensions. The resulting V-cycle multigrid methods used in preconditioned conjugate gradient iterations appear to perform similar to those of the geometrically refined case.
Can all heritable biology really be reduced to a single dimension?
Babbitt, Gregory A; Coppola, Erin E; Alawad, Mohammed A; Hudson, André O
2016-03-10
A long-held presupposition in the field of bioinformatics holds that genetic, and now even epigenetic 'information' can be abstracted from the physicochemical details of the macromolecular polymers in which it resides. It is perhaps rather ironic that this basic conjecture originated upon the first observations of DNA structure itself. This static model of DNA led very quickly to the conclusion that only the nucleobase sequence itself is rich enough in molecular complexity to replicate a complex biology. This idea has been pervasive throughout genomic science, higher education and popular culture ever since; to the point that most of us would accept it unquestioningly as fact. What is more alarming is that this conjecture is driving a significant portion of the technological development in modern genomics towards methods strongly rooted in DNA sequencing, thereby reducing a dynamic multi-dimensional biology into single-dimensional forms of data. Evidence countering this central tenet of bioinformatics has been quietly mounting over many decades, prompting some to propose that the genome must be studied from the perspective of its molecular reality, rather than as a body of information to be represented symbolically. Here, we explore the epistemological boundary between bioinformatics and molecular biology, and warn against an 'overtly' bioinformatic perspective. We review a selection of new bioinformatic methods that move beyond sequence-based approaches to include consideration of databased three dimensional structures. However, we also note that these hybrid methods still ignore the most important element of gene function when attempting to improve outcomes; the fourth dimension of molecular dynamics over time. Copyright © 2015 The Authors. Published by Elsevier B.V. All rights reserved.
Bożejko, M.; Lytvynov, E. W.; Rodionova, I. V.
2015-10-01
Let ν be a finite measure on R whose Laplace transform is analytic in a neighbourhood of zero. An anyon Lévy white noise on ( R^d,dx) is a certain family of noncommuting operators on the anyon Fock space over L^2( R^d× R,dx\\otimesν), where \\varphi=\\varphi(x) runs over a space of test functions on R^d, while ω=ω(x) is interpreted as an operator-valued distribution on R^d. Let L^2(τ) be the noncommutative L^2-space generated by the algebra of polynomials in the variables , where τ is the vacuum expectation state. Noncommutative orthogonal polynomials in L^2(τ) of the form are constructed, where f(n) is a test function on ( R^d)^n, and are then used to derive a unitary isomorphism U between L^2(τ) and an extended anyon Fock space \\mathbf F(L^2( R^d,dx)) over L^2( R^d,dx). The usual anyon Fock space \\mathscr F(L^2( R^d,dx)) over L^2( R^d,dx) is a subspace of \\mathbf F(L^2( R^d,dx)). Furthermore, the equality \\mathbf F(L^2( R^d,dx))=\\mathscr F(L^2( R^d,dx)) holds if and only if the measure ν is concentrated at a single point, that is, in the Gaussian or Poisson case. With use of the unitary isomorphism U, the operators are realized as a Jacobi (that is, tridiagonal) field in \\mathbf F(L^2( R^d,dx)). A Meixner-type class of anyon Lévy white noise is derived for which the corresponding Jacobi field in \\mathbf F(L^2( R^d,dx)) has a relatively simple structure. Each anyon Lévy white noise of Meixner type is characterized by two parameters, λ\\in R and η≥slant0. In conclusion, the representation ω(x)=\\partial_x^\\dag +λ \\partial_x^\\dag\\partialx +η\\partial_x^\\dag\\partial_x\\partial_x+\\partial_x is obtained, where \\partial_x and \\partial_x^\\dag are the annihilation and creation operators at the point x. Bibliography: 57 titles.
International Nuclear Information System (INIS)
Gui Xuewen; Cai Qi; Luo Bangqi
2007-01-01
A two-group three-dimension space-time neutron kinetics model is applied to the RELAP5 code, which replaces the point reactor kinetics model. A visual operation interface is designed to convenience interactive operation between operator and computer. The calculation results and practical applications indicate that the functions and precision of improved RELAP5 are enhanced and can be easily used. The improved RELAP5 has a good application perspective in nuclear power plant simulation. (authors)
Mitigating radiation damage of single photon detectors for space applications
Energy Technology Data Exchange (ETDEWEB)
Anisimova, Elena; Higgins, Brendon L.; Bourgoin, Jean-Philippe [University of Waterloo, Institute for Quantum Computing, Waterloo, ON (Canada); University of Waterloo, Department of Physics and Astronomy, Waterloo, ON (Canada); Cranmer, Miles [University of Waterloo, Institute for Quantum Computing, Waterloo, ON (Canada); Choi, Eric [University of Waterloo, Institute for Quantum Computing, Waterloo, ON (Canada); Magellan Aerospace, Ottawa, ON (Canada); Hudson, Danya; Piche, Louis P.; Scott, Alan [Honeywell Aerospace (formerly COM DEV Ltd.), Ottawa, ON (Canada); Makarov, Vadim [University of Waterloo, Institute for Quantum Computing, Waterloo, ON (Canada); University of Waterloo, Department of Physics and Astronomy, Waterloo, ON (Canada); University of Waterloo, Department of Electrical and Computer Engineering, Waterloo, ON (Canada); Jennewein, Thomas [University of Waterloo, Institute for Quantum Computing, Waterloo, ON (Canada); University of Waterloo, Department of Physics and Astronomy, Waterloo, ON (Canada); Canadian Institute for Advanced Research, Quantum Information Science Program, Toronto, ON (Canada)
2017-12-15
Single-photon detectors in space must retain useful performance characteristics despite being bombarded with sub-atomic particles. Mitigating the effects of this space radiation is vital to enabling new space applications which require high-fidelity single-photon detection. To this end, we conducted proton radiation tests of various models of avalanche photodiodes (APDs) and one model of photomultiplier tube potentially suitable for satellite-based quantum communications. The samples were irradiated with 106 MeV protons at doses approximately equivalent to lifetimes of 0.6, 6, 12 and 24 months in a low-Earth polar orbit. Although most detection properties were preserved, including efficiency, timing jitter and afterpulsing probability, all APD samples demonstrated significant increases in dark count rate (DCR) due to radiation-induced damage, many orders of magnitude higher than the 200 counts per second (cps) required for ground-to-satellite quantum communications. We then successfully demonstrated the mitigation of this DCR degradation through the use of deep cooling, to as low as -86 C. This achieved DCR below the required 200 cps over the 24 months orbit duration. DCR was further reduced by thermal annealing at temperatures of +50 to +100 C. (orig.)
Hydrogen atom in space with a compactified extra dimension and potential defined by Gauss' law
Czech Academy of Sciences Publication Activity Database
Bureš, M.; Siegl, Petr
2015-01-01
Roč. 354, MAR (2015), s. 316-327 ISSN 0003-4916 Grant - others:GA ČR(CZ) GD202/08/H072 Institutional support: RVO:61389005 Keywords : extra dimensions * hydrogen atom * quantum stability Subject RIV: BE - Theoretical Physics Impact factor: 2.375, year: 2015
Single-well tracer push-pull test sensitivity w. r. to fracture aperture and spacing
Ghergut, I.; Behrens, H.; Karmakar, S.; Sauter, M.
2012-04-01
Dealing with a parallel-fracture system of infinite lateral extension, four characteristic regimes of tracer signal sensitivity w. r. to fracture aperture and w. r. to fracture spacing s (whose reciprocal defines fracture density, or the fluid-rock interface area per volume) can be identified during the pull phase of a single-well push-pull test, also depending upon the ratio between push-phase duration Tpush and a characteristic time scale Ts (defined by s2 / D = Ts , with D denoting the tracer's effective diffusion coefficient): early-time regime: tracer signals are sensitive w. r. to fracture aperture, but insensitive w. r. to fracture spacing; sensitivity w. r. to fracture aperture first increases, then decreases with Tpush / Ts (thus there will be an optimum in terms of to Tpush / Ts , at early pull times); mid-time regime: tracer signals are sensitive w. r. to fracture spacing, but insensitive w. r. to fracture aperture; sensitivity w. r. to fracture spacing increases with Tpush / Ts ; late-time regime: with increasing pull duration, tracer signals become increasingly insensitive w. r. to fracture spacing, while regaining sensitivity w. r. to fracture aperture; 'very late'-time regime: sensitivity w. r. to fracture aperture becomes independent upon Tpush / Ts . From these different regimes, some recommendations can be derived regarding the design and dimensioning of dual-tracer single-well push-pull tests for the specific purposes of geothermal reservoir characterization, using conservative solutes and heat as tracers. Acknowledgement: This study is funded by MWK Niedersachsen (Lower-Saxony's Science and Culture Ministry) and by Baker Hughes (Celle) within task unit 'G6' of the Collaborative Research Project 'gebo' (Geothermal Energy and High-Performance Drilling).
Model building by coset space dimensional reduction in eight-dimensions
Jittoh, Toshifumi; Koike, Masafumi; Nomura, Takaaki; Sato, Joe; Toyama, Yutsuki
2009-05-01
We investigate gauge-Higgs unification models in eight-dimensional spacetime where extra-dimensional space has the structure of a four-dimensional compact coset space. The combinations of the coset space and the gauge group in the eight-dimensional spacetime of such models are listed. After the dimensional reduction of the coset space, we identified SO (10), SO (10) × U (1) and SO (10) × U (1) × U (1) as the possible gauge groups in the four-dimensional theory that can accomodate the Standard Model and thus is phenomenologically promising. Representations for fermions and scalars for these gauge groups are tabulated.
Energy Technology Data Exchange (ETDEWEB)
Hollmuller, P.; Lachal, B. [Universite de Geneve, Centre Universitaire d' Etude des Problemes de l' Energie (CUEPE), Geneve (Switzerland); Pahud, D. [Scuola Universitaria Professionale della Svizzera Italiana (SUPSI), Laboratorio Energia Ecologia ed Economia (LEEE), Trevano-Canobbio (Switzerland)
2005-07-01
The study performed by two Swiss universities considers two types of passive systems for space cooling: geocooling using vertical underground borehole heat exchangers and geocooling by means of horizontal underground heat exchangers placed at low depth ('canadian wells'). The goal of the study was to summarize the experience gained from ten existing Swiss geocooling installations in order to establish a basis for a dimensioning manual for future projects. For both types of geothermal probes, rules of the thumb were derived. Methods for dimensioning the heat exchangers based on computer simulation of various complexity are also presented. Presently, the least known factor is the coupling of the building to the cooling source. Therefore, future geocooling systems should be considered as an integral part of a building and not just as an additional cooling system.
Gauge-Higgs Unification Models in Six Dimensions with S2/Z2 Extra Space and GUT Gauge Symmetry
Directory of Open Access Journals (Sweden)
Cheng-Wei Chiang
2012-01-01
Full Text Available We review gauge-Higgs unification models based on gauge theories defined on six-dimensional spacetime with S2/Z2 topology in the extra spatial dimensions. Nontrivial boundary conditions are imposed on the extra S2/Z2 space. This review considers two scenarios for constructing a four-dimensional theory from the six-dimensional model. One scheme utilizes the SO(12 gauge symmetry with a special symmetry condition imposed on the gauge field, whereas the other employs the E6 gauge symmetry without requiring the additional symmetry condition. Both models lead to a standard model-like gauge theory with the SU(3×SU(2L×U(1Y(×U(12 symmetry and SM fermions in four dimensions. The Higgs sector of the model is also analyzed. The electroweak symmetry breaking can be realized, and the weak gauge boson and Higgs boson masses are obtained.
Bloch surface waves confined in one dimension with a single polymeric nanofibre
Wang, Ruxue; Xia, Hongyan; Zhang, Douguo; Chen, Junxue; Zhu, Liangfu; Wang, Yong; Yang, Erchan; Zang, Tianyang; Wen, Xiaolei; Zou, Gang; Wang, Pei; Ming, Hai; Badugu, Ramachandram; Lakowicz, Joseph R.
2017-02-01
Polymeric fibres with small radii (such as ≤125 nm) are delicate to handle and should be laid down on a solid substrate to obtain practical devices. However, placing these nanofibres on commonly used glass substrates prevents them from guiding light. In this study, we numerically and experimentally demonstrate that when the nanofibre is placed on a suitable dielectric multilayer, it supports a guided mode, a Bloch surface wave (BSW) confined in one dimension. The physical origin of this new mode is discussed in comparison with the typical two-dimensional BSW mode. Polymeric nanofibres are easily fabricated to contain fluorophores, which make the dielectric nanofibre and multilayer configuration suitable for developing a large range of new nanometric scale devices, such as processor-memory interconnections, devices with sensitivity to target analytes, incident polarization and multi-colour BSW modes.
Liu, Yuanchao; Liu, Ming; Wang, Xin
2015-01-01
The objective of text clustering is to divide document collections into clusters based on the similarity between documents. In this paper, an extension-based feature modeling approach towards semantically sensitive text clustering is proposed along with the corresponding feature space construction and similarity computation method. By combining the similarity in traditional feature space and that in extension space, the adverse effects of the complexity and diversity of natural language can be addressed and clustering semantic sensitivity can be improved correspondingly. The generated clusters can be organized using different granularities. The experimental evaluations on well-known clustering algorithms and datasets have verified the effectiveness of our approach.
Directory of Open Access Journals (Sweden)
Yuanchao Liu
Full Text Available The objective of text clustering is to divide document collections into clusters based on the similarity between documents. In this paper, an extension-based feature modeling approach towards semantically sensitive text clustering is proposed along with the corresponding feature space construction and similarity computation method. By combining the similarity in traditional feature space and that in extension space, the adverse effects of the complexity and diversity of natural language can be addressed and clustering semantic sensitivity can be improved correspondingly. The generated clusters can be organized using different granularities. The experimental evaluations on well-known clustering algorithms and datasets have verified the effectiveness of our approach.
Wilson, Neil E; Burns, Brian L; Iqbal, Zohaib; Thomas, M Albert
2015-11-01
To implement a 5D (three spatial + two spectral) correlated spectroscopic imaging sequence for application to human calf. Nonuniform sampling was applied across the two phase encoded dimensions and the indirect spectral dimension of an echo planar-correlated spectroscopic imaging sequence. Reconstruction was applied that minimized the group sparse mixed ℓ2,1-norm of the data. Multichannel data were compressed using a sensitivity map-based approach with a spatially dependent transform matrix and utilized the self-sparsity of the individual coil images to simplify the reconstruction. Single channel data with 8× and 16× undersampling are shown in the calf of a diabetic patient. A 15-channel scan with 12× undersampling of a healthy volunteer was reconstructed using 5 virtual channels and compared to a fully sampled single slice scan. Group sparse reconstruction faithfully reconstructs the lipid cross peaks much better than ℓ1 minimization. COSY spectra can be acquired over a 3D spatial volume with scan time under 15 min using echo planar readout with highly undersampled data and group sparse reconstruction. © 2015 Wiley Periodicals, Inc.
Asymptotic behavior of solutions of the damped Boussinesq equation in two space dimensions
Directory of Open Access Journals (Sweden)
Vladimir V. Varlamov
1999-01-01
classical solution is proved and the solution is constructed in the form of a series. The major term of its long-time asymptotics is calculated explicitly and a uniform in space estimate of the residual term is given.
Center deviation of localized modes in a one-dimension anharmonic single impurity chain
Chen, Xuan-Lin; Zhu, Gang-Bei; Jiang, Ze-Hui; Yang, Yan-Qiang
2018-04-01
A 1D anharmonic chain with a single impurity particle is used to study the center deviation and stability of the localized modes. The displacement patterns of the localized modes for a variable impurity mass and anharmonic parameter are studied. The pattern center is shifted away from the impurity with decreasing anharmonic parameter for both symmetric and asymmetric anharmonic impurity modes. In the limit of a heavy-mass impurity, the energy localization is constrained to the three particles nearest to the impurity.
Niemi, Antti
2013-05-01
We revisit the finite element analysis of convection-dominated flow problems within the recently developed Discontinuous Petrov-Galerkin (DPG) variational framework. We demonstrate how test function spaces that guarantee numerical stability can be computed automatically with respect to the optimal test space norm. This makes the DPG method not only stable but also robust, that is, uniformly stable with respect to the Péclet number in the current application. We employ discontinuous piecewise Bernstein polynomials as trial functions and construct a subgrid discretization that accounts for the singular perturbation character of the problem to resolve the corresponding optimal test functions. We also show that a smooth B-spline basis has certain computational advantages in the subgrid discretization. The overall effectiveness of the algorithm is demonstrated on two problems for the linear advection-diffusion equation. © 2011 Elsevier B.V.
Phase space isometries and equivariant localization of path integrals in two dimensions
International Nuclear Information System (INIS)
Szabo, Richard J.; Semenoff, Gordon W.
1994-01-01
By considering the most general metric which can occur on a simply-connected two-dimensional symplectic manifold, we find the most general hamiltonians on a two-dimensional phase space to which equivariant localization formulas for the associated path integrals can be applied. We show that in the case of a maximally symmetric phase space the only applicable hamiltonians are essentially harmonic oscillators, while for nonhomogeneous phase spaces the possibilities are more numerous but ambiguities in the path integrals occur. In the latter case we give general formulas for the Darboux hamiltonians, as well as the hamiltonians which result naturally from a generalized coherent state formulation of the quantum theory which shows that again the hamiltonians so obtained are just generalized versions of harmonic oscillators. Our analysis and results describe the quantum geometry of some two-dimensional systems. ((orig.))
An improvement of dimension-free Sobolev imbeddings in r spaces
Czech Academy of Sciences Publication Activity Database
Fiorenza, A.; Krbec, Miroslav; Schmeisser, H.-J.
2014-01-01
Roč. 267, č. 1 (2014), s. 243-261 ISSN 0022-1236 R&D Projects: GA ČR GAP201/10/1920 Institutional support: RVO:67985840 Keywords : imbedding theorem * small Lebesgue space * rearrangement-invariant Banach Subject RIV: BA - General Mathematics Impact factor: 1.322, year: 2014 http://www.sciencedirect.com/science/article/pii/S0022123614001724
Waalkens, Holger; Burbanks, Andrew; Wiggins, Stephen
2004-01-01
The three-dimensional hydrogen cyanide/isocyanide isomerization problem is taken as an example to present a general theory for computing the phase space structures which govern classical reaction dynamics in systems with an arbitrary (finite) number of degrees of freedom. The theory, which is
Male involvement: the missing dimension in promoting child spaCIng
African Journals Online (AJOL)
and societies to adopt child spacing methods Immediately with open arms. There is need for programme pla~ners, those ... Obviously, if one wishes to promote chIld spacmg, It s necessary to gain the confidence of men as well as ~.omen: ThiS study has mainly been an initial enquiry into prevaIlmg attItudes amongst.
Marchis, F.; Enriquez, J. E.; Emery, J. P.; Mueller, M.; Baek, M.; Pollock, J.; Assafin, M.; Vieira Martins, R.; Berthier, J.; Vachier, F.; Cruikshank, D. P.; Lim, L. F.; Reichart, D. E.; Ivarsen, K. M.; Haislip, J. B.; LaCluyze, A. P.
2012-01-01
We collected mid-IR spectra from 5.2 to 38 μm using the Spitzer Space Telescope Infrared Spectrograph of 28 asteroids representative of all established types of binary groups. Photometric lightcurves were also obtained for 14 of them during the Spitzer observations to provide the context of the
Single walled carbon nanotubes: a model system for excitons in one dimension
Lefebvre, J.; Finnie, P.
2011-03-01
The semiconducting single walled carbon nanotube (s-SWNTs) with its direct bandgap and its strong 1D character absorbs and emits light efficiently. In contrast with other nanomaterials, the structure of an SWNT is uniquely defined and is set by a discrete number of carbon rings along its tubular section. Experimentally, optical spectroscopy has recently revealed this remarkable quantization. In our group, we focus primarily on the luminescence properties of individual s-SWNTs. Using imaging techniques, we reveal unambiguously that each s-SWNT with its quantized structure is characterized by a specific manifold of excitonic states. With the large diameter tunability achieved in SWNTs, we show that the material represents a model system for 1D photophysics. This proceeding is meant to be a review of past work and includes complementary data that have been presented at conferences but otherwise have never been published. Some emphasis is given on experimental details for luminescence imaging and spectroscopy.
Infinite-parametric extension of the conformal algebra in D>2 space-time dimension
International Nuclear Information System (INIS)
Fradkin, E.S.; Linetsky, V.Ya.
1990-09-01
On the basis of the analytic continuations of semisimple Lie algebras discovered recently by us we construct manifestly quasiconformal infinite-dimensional algebras AC(so(4,1)) and PAC(so(3,2)) extending the conformal algebras in three-dimensional Euclidean and Minkowski space-time like the Virasoro algebra extends so(2,1). Their higher spin generalizations are also constructed. A counterpart of the central extension for D>2 and possible applications in exactly solvable conformal quantum field models in D>2 are discussed. (author). 31 refs, 2 figs
A Space-Qualified Single Frequency Fiber Laser for LISA Project
National Aeronautics and Space Administration — Single frequency high power lasers have been considered to be an enabling technology for NASA's Laser Interferometer Space Antenna (LISA). PolarOnyx proposes, for...
Single Molecule 3D Orientation in Time and Space
Börner, Richard; Ehrlich, Nicky; Hohlbein, Johannes; Hübner, Christian G.
2016-01-01
Interactions between single molecules profoundly depend on their mutual three-dimensional orientation. Recently, we demonstrated a technique that allows for orientation determination of single dipole emitters using a polarization-resolved distribution of fluorescence into several detection
Marchis, F.; Enriquez, J. E.; Emery, J. P.; Mueller, M.; Baek, M.; Pollock, J.; Assafin, M.; Matins, R. Vieira; Berthier, J.; Vachier, F.;
2012-01-01
We collected mid-IR spectra from 5.2 to 38 microns using the Spitzer Space Telescope Infrared Spectrograph of 28 asteroids representative of all established types of binary groups. Photometric light curves were also obtained for 14 of them during the Spitzer observations to provide the context of the observations and reliable estimates of their absolute magnitudes. The extracted mid-IR spectra were analyzed using a modified standard thermal model (STM) and a thermophysical model (TPM) that takes into account the shape and geometry of the large primary at the time of the Spitzer observation. We derived a reliable estimate of the size, albedo, and beaming factor for each of these asteroids, representing three main taxonomic groups: C, S, and X. For large (volume-equivalent system diameter Deq > 130 km) binary asteroids, the TPM analysis indicates a low thermal inertia (Lambda thermally insulating regolith. The smaller (surface-equivalent system diameter Deff < 17 km) asteroids also show some emission lines of minerals, but they are significantly weaker, consistent with regoliths with coarser grains, than those of the large binary asteroids. The average bulk densities of these multiple asteroids vary from 0.7-1.7 g/cu cm (P-, C-type) to approx. 2 g/cu cm (S-type). The highest density is estimated for the M-type (22) Kalliope (3.2 +/- 0.9 g/cu cm). The spectral energy distributions (SEDs) and emissivity spectra, made available as a supplement document, could help to constrain the surface compositions of these asteroids.
Single-Bunch Stability With Direct Space Charge
Oeftiger, Adrian
2017-01-01
Previous studies have shown the suppressing effect of direct space charge on impedance-driven head-tail instabilities. The present work investigates transverse stability for the HL-LHC scenario based on our macro-particle simulation tool PyHEADTAIL using realistic bunch distributions. The impact of selfconsistent modelling is briefly discussed for non-linear space charge forces. We study how space charge pushes the instability threshold for the transverse mode coupling instability (TMCI) occurring between mode 0 and -1. Next we consider finite chromaticity: in absence of space charge, the impedance model predicts head-tail instabilities. For a selected case below TMCI threshold at Q0 = 5, we demonstrate the stabilising effect of space charge. Finally, we compare simulation results to past LHC measurements.
An Asymmetrical Space Vector Method for Single Phase Induction Motor
DEFF Research Database (Denmark)
Cui, Yuanhai; Blaabjerg, Frede; Andersen, Gert Karmisholt
2002-01-01
the motor torque performance is not good enough. This paper addresses a new control method, an asymmetrical space vector method with PWM modulation, also a three-phase inverter is used for the main winding and the auxiliary winding. This method with PWM modulation is implemented to control the motor speed...
mode of collapse of square single panel reinforced concrete space
African Journals Online (AJOL)
The behavior of the structural elements of a space-framed structure depends on their support conditions. These support conditions can be hinged or rigid for beam-column joints, while for slab these support conditions can be simply supported on walls that are not monolithically constructed together, simply supported on ...
mode of collapse of square single panel reinforced concrete space
African Journals Online (AJOL)
eobe
column .... develop safe design recommendations, a database of ..... The shear capacity V of a section for a given stirrup size and spacing can be estimated from Equation (15):. = 0.95 +. (15). Here, Asv is the area of shear reinforcement provided.
Fast single image super-resolution using estimated low-frequency k-space data in MRI.
Luo, Jianhua; Mou, Zhiying; Qin, Binjie; Li, Wanqing; Yang, Feng; Robini, Marc; Zhu, Yuemin
2017-07-01
Single image super-resolution (SR) is highly desired in many fields but obtaining it is often technically limited in practice. The purpose of this study was to propose a simple, rapid and robust single image SR method in magnetic resonance (MR) imaging (MRI). The idea is based on the mathematical formulation of the intrinsic link in k-space between a given (modulus) low-resolution (LR) image and the desired SR image. The method consists of two steps: 1) estimating the low-frequency k-space data of the desired SR image from a single LR image; 2) reconstructing the SR image using the estimated low-frequency and zero-filled high-frequency k-space data. The method was evaluated on digital phantom images, physical phantom MR images and real brain MR images, and compared with existing SR methods. The proposed SR method exhibited a good robustness by reaching a clearly higher PSNR (25.77dB) and SSIM (0.991) averaged over different noise levels in comparison with existing edge-guided nonlinear interpolation (EGNI) (PSNR=23.78dB, SSIM=0.983), zero-filling (ZF) (PSNR=24.09dB, SSIM=0.985) and total variation (TV) (PSNR=24.54dB, SSIM=0.987) methods while presenting the same order of computation time as the ZF method but being much faster than the EGNI or TV method. The average PSNR or SSIM over different slice images of the proposed method (PSNR=26.33 dB or SSIM=0.955) was also higher than the EGNI (PSNR=25.07dB or SSIM=0.952), ZF (PSNR=24.97dB or SSIM=0.950) and TV (PSNR=25.70dB or SSIM=0.953) methods, demonstrating its good robustness to variation in anatomical structure of the images. Meanwhile, the proposed method always produced less ringing artifacts than the ZF method, gave a clearer image than the EGNI method, and did not exhibit any blocking effect presented in the TV method. In addition, the proposed method yielded the highest spatial consistency in the inter-slice dimension among the four methods. This study proposed a fast, robust and efficient single image SR
An Asymmetrical Space Vector Method for Single Phase Induction Motor
DEFF Research Database (Denmark)
Cui, Yuanhai; Blaabjerg, Frede; Andersen, Gert Karmisholt
2002-01-01
Single phase induction motors are the workhorses in low-power applications in the world, and also the variable speed is necessary. Normally it is achieved either by the mechanical method or by controlling the capacitor connected with the auxiliary winding. Any above method has some drawback which...
Single-mode multicore fiber for dense space division multiplexing
DEFF Research Database (Denmark)
Sasaki, Yusuke; Amma, Yoshimichi; Takenaga, Katsuhiro
2016-01-01
Single-mode multicore fiber (SM-MCF) is attractive for high-capacity transmission. Our fabricated SM-MCFs achieve high core count and low crosstalk with a cladding diameter of 230 µm. Characteristics of fan-in/fan-out for the SM-MCFs are also investigated....
Biological Nanopores: Confined Spaces for Electrochemical Single-Molecule Analysis.
Cao, Chan; Long, Yi-Tao
2018-02-20
Nanopore sensing is developing into a powerful single-molecule approach to investigate the features of biomolecules that are not accessible by studying ensemble systems. When a target molecule is transported through a nanopore, the ions occupying the pore are excluded, resulting in an electrical signal from the intermittent ionic blockade event. By statistical analysis of the amplitudes, duration, frequencies, and shapes of the blockade events, many properties of the target molecule can be obtained in real time at the single-molecule level, including its size, conformation, structure, charge, geometry, and interactions with other molecules. With the development of the use of α-hemolysin to characterize individual polynucleotides, nanopore technology has attracted a wide range of research interest in the fields of biology, physics, chemistry, and nanoscience. As a powerful single-molecule analytical method, nanopore technology has been applied for the detection of various biomolecules, including oligonucleotides, peptides, oligosaccharides, organic molecules, and disease-related proteins. In this Account, we highlight recent developments of biological nanopores in DNA-based sensing and in studying the conformational structures of DNA and RNA. Furthermore, we introduce the application of biological nanopores to investigate the conformations of peptides affected by charge, length, and dipole moment and to study disease-related proteins' structures and aggregation transitions influenced by an inhibitor, a promoter, or an applied voltage. To improve the sensing ability of biological nanopores and further extend their application to a wider range of molecular sensing, we focus on exploring novel biological nanopores, such as aerolysin and Stable Protein 1. Aerolysin exhibits an especially high sensitivity for the detection of single oligonucleotides both in current separation and duration. Finally, to facilitate the use of nanopore measurements and statistical analysis
Single Frequency Lasers for Space-Based Wind and Aerosol Lidar, Phase I
National Aeronautics and Space Administration — This SBIR will develop single frequency cw laser technology for 2um lidar and UV interferometer locking control critical to NASA missions that will measure...
Every cell is special: genome-wide studies add a new dimension to single-cell biology.
Junker, Jan Philipp; van Oudenaarden, Alexander
2014-03-27
Single-cell analyses have provided invaluable insights into studying heterogenity, signaling, and stochastic gene expression. Recent technological advances now open the door to genome-wide single-cell studies. Copyright © 2014 Elsevier Inc. All rights reserved.
Every cell is special : genome-wide studies add a new dimension to single-cell biology
Junker, Jan Philipp; van Oudenaarden, Alexander
2014-01-01
Single-cell analyses have provided invaluable insights into studying heterogenity, signaling, and stochastic gene expression. Recent technological advances now open the door to genome-wide single-cell studies.
DEFF Research Database (Denmark)
Peng, Min; Fei, Wei; Hosseini, Mandana
2013-01-01
The aims of the present study were to evaluate the influence of implant position on clinical crown length and marginal soft tissue dimensions at implant-supported single crowns of maxillary central incisors, and to validate the papilla index score (PIS). Twenty-five patients, who had lost one...... as controls. Paired sample t-testand Pearson´s correlation analysis were used to analyze implant position, dimension of crownand papilla fill.Cohen’s ¿ andSpearman correlation were used to validate the PIS.The implant-supported crown was statistically longer than the contra-lateral tooth......, and there was significant correlation between the oro-facial position of the implant and the crown length difference (r=.607, p=.001). The distalpapilla was significantly shorter than the mesialpapilla at implant-supported crowns (ptooth (p=.415...
Integration of neutron time-of-flight single-crystal Bragg peaks in reciprocal space
Energy Technology Data Exchange (ETDEWEB)
Schultz, Arthur J [ORNL; Joergensen, Mads [ORNL; Wang, Xiaoping [ORNL; Mikkelson, Ruth L [ORNL; Mikkelson, Dennis J [ORNL; Lynch, Vickie E [ORNL; Peterson, Peter F [ORNL; Green, Mark L [ORNL; Hoffmann, Christina [ORNL
2014-01-01
The intensity of single crystal Bragg peaks obtained by mapping neutron time-of-flight event data into reciprocal space and integrating in various ways are compared. These include spherical integration with a fixed radius, ellipsoid fitting and integrating of the peak intensity and one-dimensional peak profile fitting. In comparison to intensities obtained by integrating in real detector histogram space, the data integrated in reciprocal space results in better agreement factors and more accurate atomic parameters. Furthermore, structure refinement using integrated intensities from one-dimensional profile fitting is demonstrated to be more accurate than simple peak-minus-background integration.
Empirical formulae for excess noise factor with dead space for single carrier multiplication
Dehwah, Ahmad H.
2011-09-01
In this letter, two empirical equations are presented for the calculation of the excess noise factor of an avalanche photodiode for single carrier multiplication including the dead space effect. The first is an equation for calculating the excess noise factor when the multiplication approaches infinity as a function of parameters that describe the degree of the dead space effect. The second equation can be used to find the minimum value of the excess noise factor for any multiplication when the dead space effect is completely dominant, the so called "deterministic" limit. This agrees with the theoretically known equation for multiplications less than or equal to two. © 2011 World Scientific Publishing Company.
CERN. Geneva
2006-01-01
Extra dimensions of space might be present in our universe. If so, we want to know 'How do dimensions hide?' and 'Why are three dimensions special?' I'll give potential answers to both these questions in the context of localized gravity. Organiser(s): L. Alvarez-Gaume / PH-THNote: * Tea & coffee will be served at 16:00. Talk is broadcasted in Council Chamber
Types and Dynamics of Gendered Space: A Case of Emirati Female Learners in a Single-Gender Context
Alzeer, Gergana
2018-01-01
This article is concerned with gendered spaces as they emerge from exploring Emirati female learners' spatiality in a single-gender context. By conducting ethnographic research and utilising Lefebvre's triad of perceived, conceived and lived space for the analysis and categorisation of students' spaces, three types of gendered spaces emerged:…
Polek, Ela; Jones, Peter B; Fearon, Pasco; Brodbeck, Jeannette; Moutoussis, Michael; Nspn Consortium; Dolan, Ray; Fonagy, Peter; Bullmore, Edward T; Goodyer, Ian M
2018-01-26
Personality with stable behavioural traits emerges in the adolescent and young adult years. Models of putatively distinct, but correlated, personality traits have been developed to describe behavioural styles including schizotypal, narcissistic, callous-unemotional, negative emotionality, antisocial and impulsivity traits. These traits have influenced the classification of their related personality disorders. We tested if a bifactor model fits the data better than correlated-factor and orthogonal-factor models and subsequently validated the obtained factors with mental health measures and treatment history. A set of self-report questionnaires measuring the above traits together with measures of mental health and service use were collected from a volunteer community sample of adolescents and young adults aged 14 to 25 years (N = 2443). The bifactor model with one general and four specific factors emerged in exploratory analysis, which fit data better than models with correlated or orthogonal factors. The general factor showed high reliability and validity. The findings suggest that a selected range of putatively distinct personality traits is underpinned by a general latent personality trait that may be interpreted as a severity factor, with higher scores indexing more impairment in social functioning. The results are in line with ICD-11, which suggest an explicit link between personality disorders and compromised interpersonal or social function. The obtained general factor was akin to the overarching dimension of personality functioning (describing one's relation to the self and others) proposed by DSM-5 Section III.
Digital atom interferometer with single particle control on a discretized space-time geometry.
Steffen, Andreas; Alberti, Andrea; Alt, Wolfgang; Belmechri, Noomen; Hild, Sebastian; Karski, Michał; Widera, Artur; Meschede, Dieter
2012-06-19
Engineering quantum particle systems, such as quantum simulators and quantum cellular automata, relies on full coherent control of quantum paths at the single particle level. Here we present an atom interferometer operating with single trapped atoms, where single particle wave packets are controlled through spin-dependent potentials. The interferometer is constructed from a sequence of discrete operations based on a set of elementary building blocks, which permit composing arbitrary interferometer geometries in a digital manner. We use this modularity to devise a space-time analogue of the well-known spin echo technique, yielding insight into decoherence mechanisms. We also demonstrate mesoscopic delocalization of single atoms with a separation-to-localization ratio exceeding 500; this result suggests their utilization beyond quantum logic applications as nano-resolution quantum probes in precision measurements, being able to measure potential gradients with precision 5 x 10(-4) in units of gravitational acceleration g.
International Nuclear Information System (INIS)
Dobrev, V. K.; Stoimenov, S.
2010-01-01
The singular vectors in Verma modules over the Schroedinger algebra s(n) in (n + 1)-dimensional space-time are found for the case of general representations. Using the singular vectors, hierarchies of equations invariant under Schroedinger algebras are constructed.
Channel analysis for single photon underwater free space quantum key distribution.
Shi, Peng; Zhao, Shi-Cheng; Gu, Yong-Jian; Li, Wen-Dong
2015-03-01
We investigate the optical absorption and scattering properties of underwater media pertinent to our underwater free space quantum key distribution (QKD) channel model. With the vector radiative transfer theory and Monte Carlo method, we obtain the attenuation of photons, the fidelity of the scattered photons, the quantum bit error rate, and the sifted key generation rate of underwater quantum communication. It can be observed from our simulations that the most secure single photon underwater free space QKD is feasible in the clearest ocean water.
Space-qualified silicon avalanche-photodiode single-photon-counting modules
Sun, Xiaoli; Krainak, Michael A.; Abshire, James B.; Spinhirne, James D.; Trottier, Claude; Davies, Murray; Dautet, Henri; Allan, Graham R.; Lukemire, Alan T.; Vandiver, James C.
2004-09-01
A space-qualified silicon avalanche-photodiode (APD) based single-photon-counting-module (SPCM) was developed for the Geoscience Laser Altimeter System (GLAS) on board NASA's Ice, Cloud, and Land Elevation Satellite (ICESat). Numerous improvements were made over the commercially available SPCMs in both performance and reliability. The measured optoelectronic parameters include, 65% photon detection efficiency at the 532 nm wavelength, 15-17 mega-counts per second (Mcps) maximum count rate and less than 200 s-1 dark counts before exposure to space radiation.
Directory of Open Access Journals (Sweden)
N P Narbut
2014-12-01
Full Text Available The set of mechanisms for the implementation of the idea of the single European space of higher education including the access to higher education, advice and guidance for the students, their material support, providing equal opportunities and social equality allows the majority of young people to achieve a high level of education and facilitates their personal self-realization. The social dimension as one of the areas of the Bologna process implementations was first announced in the context of mobility support and the strategy of lifelong learning, in the present time it is a complex system of social support for students including accommodation, medical care, nutrition and other social services. All these aspects of the social dimension of the students’ life have become the subject of the European research project Eurostudent taking place in 25 European countries. Russia for the first time took part in this project as an associate member: in the spring of 2014, we conducted a survey with the methodology of the international research project. The methodological issues of the project techniques are considered in the article as well as some conclusions based on the results of the survey conducted at the People’s Friendship University of Russia.
A COTS-based single board radiation-hardened computer for space applications
International Nuclear Information System (INIS)
Stewart, S.; Hillman, R.; Layton, P.; Krawzsenek, D.
1999-01-01
There is great community interest in the ability to use COTS (Commercial-Off-The-Shelf) technology in radiation environments. Space Electronics, Inc. has developed a high performance COTS-based radiation hardened computer. COTS approaches were selected for both hardware and software. Through parts testing, selection and packaging, all requirements have been met without parts or process development. Reliability, total ionizing dose and single event performance are attractive. The characteristics, performance and radiation resistance of the single board computer will be presented. (authors)
Pose determination of a blade implant in three dimensions from a single two-dimensional radiograph.
Toti, Paolo; Barone, Antonio; Marconcini, Simone; Menchini-Fabris, Giovanni Battista; Martuscelli, Ranieri; Covani, Ugo
2018-01-11
The aim of the study was to introduce a mathematical method to estimate the correct pose of a blade by evaluating the radiographic features obtained from a single two-dimensional image. Blade-form implant bed preparation was performed using the piezosurgery device, and placement was attained with the use of magnetic mallet. The pose determination of the blade was described by means of three consecutive rotations defined by three angles of orientation (triplet φ, θ and ψ). Retrospective analysis on periapical radiographs was performed. This method was used to compare implant (axial length along the marker, i.e. the implant structure) vs angular correction factor (a trigonometric function of the triplet). The accuracy of the method was tested by generating two-dimensional radiographic simulations of the blades, which were then compared with the images of the implants as appearing on the real radiographs. Two patients had to be excluded from further evaluation because the values of the estimated pose angles showed a too-wide range to be effective for a good standardization of serial radiographs: intrapatient range from baseline to 1-year survey was > of a threshold determined by the clinicians (30°). The linear dependence between implant (CF°) and angular correction factor (CF^) was estimated by a robust linear regression, yielding the following coefficients: slope, 0.908; intercept, -0.092; and coefficient of determination, 0.924. The absolute error in accuracy was -0.29 ± 4.35, 0.23 ± 3.81 and 0.64 ± 1.18°, respectively, for the angles φ, θ and ψ. The present theoretical and experimental study established the possibility of determining, a posteriori, a unique triplet of angles (φ, θ and ψ) which described the pose of a blade upon a single two-dimensional radiograph, and of suggesting a method to detect cases in which the standardized geometric projection failed. The angular correction of the bone level yielded results very close to those obtained
Directory of Open Access Journals (Sweden)
Eduardo Pimentel Pizarro
2016-12-01
Full Text Available The favelas constitute a consolidated reality in the city of São Paulo, concentrating more than 10% of its total population. And the open space system inside the informal city represents great investigative potential in regard to its physical characteristics, to the articulation established between public and private spaces and, mostly, to the public and ordinary practices developed inside it. With this aim, the article selects three favelas in the city of São Paulo as case studies: the favela de Paraisópolis, the second biggest community in the municipality, which is located in the Morumbi neighbourhood with around 100.000 inhabitants in an area of 100 acres; the favela da Linha and the favela do Nove, which together occupy less than 2 acres in the General Stores Company of São Paulo (Ceagesp neighborhood, concentrating 630 families. Based on fieldwork, the article shows how the spatial and public dynamics work in these spaces and how they could help us discuss the open space system of the whole city.
Turchin, Peter; Currie, Thomas E.; Whitehouse, Harvey; François, Pieter; Feeney, Kevin; Mullins, Daniel; Hoyer, Daniel; Collins, Christina; Grohmann, Stephanie; Mendel-Gleason, Gavin; Turner, Edward; Dupeyron, Agathe; Cioni, Enrico; Reddish, Jenny; Levine, Jill; Jordan, Greine; Brandl, Eva; Williams, Alice; Cesaretti, Rudolf; Krueger, Marta; Ceccarelli, Alessandro; Figliulo-Rosswurm, Joe; Tuan, Po-Ju; Peregrine, Peter; Marciniak, Arkadiusz; Preiser-Kapeller, Johannes; Kradin, Nikolay; Korotayev, Andrey; Palmisano, Alessio; Baker, David; Bidmead, Julye; Bol, Peter; Christian, David; Cook, Connie; Covey, Alan; Feinman, Gary; Júlíusson, Árni Daníel; Kristinsson, Axel; Miksic, John; Mostern, Ruth; Petrie, Cameron; Rudiak-Gould, Peter; ter Haar, Barend; Wallace, Vesna; Mair, Victor; Xie, Liye; Baines, John; Bridges, Elizabeth; Manning, Joseph; Lockhart, Bruce; Bogaard, Amy; Spencer, Charles
2018-01-01
Do human societies from around the world exhibit similarities in the way that they are structured, and show commonalities in the ways that they have evolved? These are long-standing questions that have proven difficult to answer. To test between competing hypotheses, we constructed a massive repository of historical and archaeological information known as “Seshat: Global History Databank.” We systematically coded data on 414 societies from 30 regions around the world spanning the last 10,000 years. We were able to capture information on 51 variables reflecting nine characteristics of human societies, such as social scale, economy, features of governance, and information systems. Our analyses revealed that these different characteristics show strong relationships with each other and that a single principal component captures around three-quarters of the observed variation. Furthermore, we found that different characteristics of social complexity are highly predictable across different world regions. These results suggest that key aspects of social organization are functionally related and do indeed coevolve in predictable ways. Our findings highlight the power of the sciences and humanities working together to rigorously test hypotheses about general rules that may have shaped human history. PMID:29269395
Meise, Kristine; Mueller, Birte; Zein, Beate; Trillmich, Fritz
2014-01-01
Morphological features correlate with many life history traits and are therefore of high interest to behavioral and evolutionary biologists. Photogrammetry provides a useful tool to collect morphological data from species for which measurements are otherwise difficult to obtain. This method reduces disturbance and avoids capture stress. Using the Galapagos sea lion (Zalophus wollebaeki) as a model system, we tested the applicability of single-camera photogrammetry in combination with laser distance measurement to estimate morphological traits which may vary with an animal's body position. We assessed whether linear morphological traits estimated by photogrammetry can be used to estimate body length and mass. We show that accurate estimates of body length (males: ±2.0%, females: ±2.6%) and reliable estimates of body mass are possible (males: ±6.8%, females: 14.5%). Furthermore, we developed correction factors that allow the use of animal photos that diverge somewhat from a flat-out position. The product of estimated body length and girth produced sufficiently reliable estimates of mass to categorize individuals into 10 kg-classes of body mass. Data of individuals repeatedly photographed within one season suggested relatively low measurement errors (body length: 2.9%, body mass: 8.1%). In order to develop accurate sex- and age-specific correction factors, a sufficient number of individuals from both sexes and from all desired age classes have to be captured for baseline measurements. Given proper validation, this method provides an excellent opportunity to collect morphological data for large numbers of individuals with minimal disturbance.
Directory of Open Access Journals (Sweden)
Kristine Meise
Full Text Available Morphological features correlate with many life history traits and are therefore of high interest to behavioral and evolutionary biologists. Photogrammetry provides a useful tool to collect morphological data from species for which measurements are otherwise difficult to obtain. This method reduces disturbance and avoids capture stress. Using the Galapagos sea lion (Zalophus wollebaeki as a model system, we tested the applicability of single-camera photogrammetry in combination with laser distance measurement to estimate morphological traits which may vary with an animal's body position. We assessed whether linear morphological traits estimated by photogrammetry can be used to estimate body length and mass. We show that accurate estimates of body length (males: ±2.0%, females: ±2.6% and reliable estimates of body mass are possible (males: ±6.8%, females: 14.5%. Furthermore, we developed correction factors that allow the use of animal photos that diverge somewhat from a flat-out position. The product of estimated body length and girth produced sufficiently reliable estimates of mass to categorize individuals into 10 kg-classes of body mass. Data of individuals repeatedly photographed within one season suggested relatively low measurement errors (body length: 2.9%, body mass: 8.1%. In order to develop accurate sex- and age-specific correction factors, a sufficient number of individuals from both sexes and from all desired age classes have to be captured for baseline measurements. Given proper validation, this method provides an excellent opportunity to collect morphological data for large numbers of individuals with minimal disturbance.
Preimage entropy dimension of topological dynamical systems
Liu, Lei; Zhou, Xiaomin; Zhou, Xiaoyao
2014-01-01
We propose a new definition of preimage entropy dimension for continuous maps on compact metric spaces, investigate fundamental properties of the preimage entropy dimension, and compare the preimage entropy dimension with the topological entropy dimension. The defined preimage entropy dimension holds various basic properties of topological entropy dimension, for example, the preimage entropy dimension of a subsystem is bounded by that of the original system and topologically conjugated system...
International Nuclear Information System (INIS)
Moore, Peter K.
2003-01-01
Solving systems of reaction-diffusion equations in three space dimensions can be prohibitively expensive both in terms of storage and CPU time. Herein, I present a new incomplete assembly procedure that is designed to reduce storage requirements. Incomplete assembly is analogous to incomplete factorization in that only a fixed number of nonzero entries are stored per row and a drop tolerance is used to discard small values. The algorithm is incorporated in a finite element method-of-lines code and tested on a set of reaction-diffusion systems. The effect of incomplete assembly on CPU time and storage and on the performance of the temporal integrator DASPK, algebraic solver GMRES and preconditioner ILUT is studied
Aarts, JM
1993-01-01
Two types of seemingly unrelated extension problems are discussed in this book. Their common focus is a long-standing problem of Johannes de Groot, the main conjecture of which was recently resolved. As is true of many important conjectures, a wide range of mathematical investigations had developed, which have been grouped into the two extension problems. The first concerns the extending of spaces, the second concerns extending the theory of dimension by replacing the empty space with other spaces. The problem of de Groot concerned compactifications of spaces by means of an adjunction of a set of minimal dimension. This minimal dimension was called the compactness deficiency of a space. Early success in 1942 lead de Groot to invent a generalization of the dimension function, called the compactness degree of a space, with the hope that this function would internally characterize the compactness deficiency which is a topological invariant of a space that is externally defined by means of compact extensions of a...
Higher spin gauge theories in any dimension
International Nuclear Information System (INIS)
Vasiliev, M.A.
2004-01-01
Some general properties of higher spin (HS) gauge theories are summarized, with the emphasize on the nonlinear theories in any dimension. The main conclusion is that nonlinear HS theories exist in any dimension. Note that HS gauge symmetries in the nonlinear HS theory differ from the Yang-Mills gauging of the global HS symmetry of a free theory one starts with by HS field strength dependent nonlinear corrections resulting from the partial gauge fixing of spontaneously broken HS symmetries in the extended non-commutative space. The HS geometry is that of the fuzzy hyperboloid in the auxiliary (fiber) non-commutative space. Its radius depends on the Weyl 0-forms which take values in the infinitive-dimensional module dual to the space of single-particle states in the system
Mu, Zonggao; Han, Liang; Xu, Wenfu; Li, Bing; Liang, Bin
2016-01-01
A space manipulator plays an important role in spacecraft capturing, repairing, maintenance, and so on. However, the harsh space environment will cause its joints fail to work. For a non-redundant manipulator, single joint locked failure will cause it to lose one degree of freedom (DOF), hence reducing its movement ability. In this paper, the key problems related to the fault-tolerant including kinematics, workspace, and trajectory planning of a non-redundant space manipulator under single joint failure are handled. First, the analytical inverse kinematics equations are derived for the 5-DOF manipulator formed by locking the failure joint of the original 6-DOF manipulator. Then, the reachable end-effector pose (position and orientation) is determined. Further, we define the missions can be completed by the 5-DOF manipulator. According to the constraints of the on-orbital mission, we determine the grasp envelope required for the end-effector. Combining the manipulability of the manipulator and the performance of its end-effector, a fault tolerance parameter is defined and a planning method is proposed to generate the reasonable trajectory, based on which the 5-DOF manipulator can complete the desired tasks. Finally, typical cases are simulated and the simulation results verify the proposed method.
Sokolenko, Stanislav; Blondeel, Eric J M; Azlah, Nada; George, Ben; Schulze, Steffen; Chang, David; Aucoin, Marc G
2014-04-01
Single-dimension hydrogen, or proton, nuclear magnetic resonance spectroscopy (1D-(1)H NMR) has become an attractive option for characterizing the full range of components in complex mixtures of small molecular weight compounds due to its relative simplicity, speed, spectral reproducibility, and noninvasive sample preparation protocols compared to alternative methods. One challenge associated with this method is the overlap of NMR resonances leading to "convoluted" spectra. While this can be mitigated through "targeted profiling", there is still the possibility of increased quantification error. This work presents the application of a Plackett-Burman experimental design for the robust estimation of precision and accuracy of 1D-(1)H NMR compound quantification in synthetic mixtures, with application to mammalian cell culture supernatant. A single, 20 sample experiment was able to provide a sufficient estimate of bias and variability at different metabolite concentrations. Two major sources of bias were identified: incorrect interpretation of singlet resonances and the quantification of resonances from protons in close proximity to labile protons. Furthermore, decreases in measurement accuracy and precision could be observed with decreasing concentration for a small fraction of the components as a result of their particular convolution patterns. Finally, the importance of a priori concentration estimates is demonstrated through the example of interpreting acetate metabolite trends from a bioreactor cultivation of Chinese hamster ovary cells expressing a recombinant antibody.
Extra dimensions round the corner?
International Nuclear Information System (INIS)
Abel, S.
1999-01-01
How many dimensions are we living in? This question is fundamental and yet, astonishingly, it remains unresolved. Of course, on the everyday level it appears that we are living in four dimensions three space plus one time dimension. But in recent months theoretical physicists have discovered that collisions between high-energy particles at accelerators may reveal the presence of extra space-time dimensions. On scales where we can measure the acceleration of falling objects due to gravity or study the orbital motion of planets or satellites, the gravitational force seems to be described by a 1/r 2 law. The most sensitive direct tests of the gravitational law are based on torsion-balance experiments that were first performed by Henry Cavendish in 1798. However, the smallest scales on which this type of experiment can be performed are roughly 1 mm (see J C Long, H W Chan and J C Price 1999 Nucl. Phys. B 539 23). At smaller distances, objects could be gravitating in five or more dimensions that are rolled up or ''compactified'' - an idea that is bread-and-butter to string theorists. Most string theorists however believe that the gravitational effects of compact extra dimensions are too small to be observed. Now Nima Arkani-Hamed from the Stanford Linear Accelerator Center (SLAC) in the US, Savas Dimopoulos at Stanford University and Gia Dvali, who is now at New York University, suggest differently (Phys. Lett. B 1998 429 263). They advanced earlier ideas from string theory in which the strong, weak and electromagnetic forces are confined to membranes, like dirt particles trapped in soap bubbles, while the gravitational force operates in the entire higher-dimensional volume. In their theory extra dimensions should have observable effects inside particle colliders such as the Tevatron accelerator at Fermilab in the US or at the future Large Hadron Collider at CERN. The effect will show up as an excess of events in which a single jet of particles is produced with no
Rucker, Rudy
2014-01-01
""This is an invigorating book, a short but spirited slalom for the mind."" - Timothy Ferris, The New York Times Book Review ""Highly readable. One is reminded of the breadth and depth of Hofstadter's Gödel, Escher, Bach."" - Science""Anyone with even a minimal interest in mathematics and fantasy will find The Fourth Dimension informative and mind-dazzling... [Rucker] plunges into spaces above three with a zest and energy that is breathtaking."" - Martin Gardner ""Those who think the fourth dimension is nothing but time should be encouraged to read The Fourth Dimension, along with anyone else
International Nuclear Information System (INIS)
Yang, J.; Kondoh, T.; Kan, K.; Kozawa, T.; Yoshida, Y.; Tagawa, S.
2006-01-01
A femtosecond (fs) electron bunching was observed in a photoinjector with a magnetic compressor by rotating the bunch in longitudinal phase space. The bunch length was obtained by measuring Cherenkov radiation of the electron beam with a femtosecond streak camera technique. A single electron bunch with rms bunch length of 98 fs was observed for a 32 MeV electron beam at a charge of 0.17 nC. The relative energy spread and the normalized transverse emittance of the electron beam were 0.2% and 3.8 mm-mrad, respectively. The effect of space charge on the bunch compression was investigated experimentally for charges from 0.17 to 1.25 nC. The dependences of the relative energy spread and the normalized beam transverse emittance on the bunch charge were measured
Addressing challenges in single species assessments via a simple state-space assessment model
DEFF Research Database (Denmark)
Nielsen, Anders
Single-species and age-structured fish stock assessments still remains the main tool for managing fish stocks. A simple state-space assessment model is presented as an alternative to (semi) deterministic procedures and the full parametric statistical catch at age models. It offers a solution...... to some of the key challenges of these models. Compared to the deterministic procedures it solves a list of problems originating from falsely assuming that age classified catches are known without errors and allows quantification of uncertainties of estimated quantities of interest. Compared to full...
Accessible solitons of fractional dimension
Energy Technology Data Exchange (ETDEWEB)
Zhong, Wei-Ping, E-mail: zhongwp6@126.com [Department of Electronic and Information Engineering, Shunde Polytechnic, Guangdong Province, Shunde 528300 (China); Texas A& M University at Qatar, P.O. Box 23874, Doha (Qatar); Belić, Milivoj [Texas A& M University at Qatar, P.O. Box 23874, Doha (Qatar); Zhang, Yiqi [Key Laboratory for Physical Electronics and Devices of the Ministry of Education & Shaanxi Key Lab of Information Photonic Technique, Xi’an Jiaotong University, Xi’an 710049 (China)
2016-05-15
We demonstrate that accessible solitons described by an extended Schrödinger equation with the Laplacian of fractional dimension can exist in strongly nonlocal nonlinear media. The soliton solutions of the model are constructed by two special functions, the associated Legendre polynomials and the Laguerre polynomials in the fraction-dimensional space. Our results show that these fractional accessible solitons form a soliton family which includes crescent solitons, and asymmetric single-layer and multi-layer necklace solitons. -- Highlights: •Analytic solutions of a fractional Schrödinger equation are obtained. •The solutions are produced by means of self-similar method applied to the fractional Schrödinger equation with parabolic potential. •The fractional accessible solitons form crescent, asymmetric single-layer and multilayer necklace profiles. •The model applies to the propagation of optical pulses in strongly nonlocal nonlinear media.
Berg, Melanie; Label, Kenneth; Campola, Michael; Xapsos, Michael
2017-01-01
We propose a method for the application of single event upset (SEU) data towards the analysis of complex systems using transformed reliability models (from the time domain to the particle fluence domain) and space environment data.
On the estimation of the current density in space plasmas: Multi- versus single-point techniques
Perri, Silvia; Valentini, Francesco; Sorriso-Valvo, Luca; Reda, Antonio; Malara, Francesco
2017-06-01
Thanks to multi-spacecraft mission, it has recently been possible to directly estimate the current density in space plasmas, by using magnetic field time series from four satellites flying in a quasi perfect tetrahedron configuration. The technique developed, commonly called ;curlometer; permits a good estimation of the current density when the magnetic field time series vary linearly in space. This approximation is generally valid for small spacecraft separation. The recent space missions Cluster and Magnetospheric Multiscale (MMS) have provided high resolution measurements with inter-spacecraft separation up to 100 km and 10 km, respectively. The former scale corresponds to the proton gyroradius/ion skin depth in ;typical; solar wind conditions, while the latter to sub-proton scale. However, some works have highlighted an underestimation of the current density via the curlometer technique with respect to the current computed directly from the velocity distribution functions, measured at sub-proton scales resolution with MMS. In this paper we explore the limit of the curlometer technique studying synthetic data sets associated to a cluster of four artificial satellites allowed to fly in a static turbulent field, spanning a wide range of relative separation. This study tries to address the relative importance of measuring plasma moments at very high resolution from a single spacecraft with respect to the multi-spacecraft missions in the current density evaluation.
Inhomogeneous compact extra dimensions
Energy Technology Data Exchange (ETDEWEB)
Bronnikov, K.A. [Center of Gravity and Fundamental Metrology, VNIIMS, 46 Ozyornaya st., Moscow 119361 (Russian Federation); Budaev, R.I.; Grobov, A.V.; Dmitriev, A.E.; Rubin, Sergey G., E-mail: kb20@yandex.ru, E-mail: buday48@mail.ru, E-mail: alexey.grobov@gmail.com, E-mail: alexdintras@mail.ru, E-mail: sergeirubin@list.ru [National Research Nuclear University MEPhI (Moscow Engineering Physics Institute), 115409 Moscow (Russian Federation)
2017-10-01
We show that an inhomogeneous compact extra space possesses two necessary features— their existence does not contradict the observable value of the cosmological constant Λ{sub 4} in pure f ( R ) theory, and the extra dimensions are stable relative to the 'radion mode' of perturbations, the only mode considered. For a two-dimensional extra space, both analytical and numerical solutions for the metric are found, able to provide a zero or arbitrarily small Λ{sub 4}. A no-go theorem has also been proved, that maximally symmetric compact extra spaces are inconsistent with 4D Minkowski space in the framework of pure f ( R ) gravity.
Single image super-resolution via an iterative reproducing kernel Hilbert space method.
Deng, Liang-Jian; Guo, Weihong; Huang, Ting-Zhu
2016-11-01
Image super-resolution, a process to enhance image resolution, has important applications in satellite imaging, high definition television, medical imaging, etc. Many existing approaches use multiple low-resolution images to recover one high-resolution image. In this paper, we present an iterative scheme to solve single image super-resolution problems. It recovers a high quality high-resolution image from solely one low-resolution image without using a training data set. We solve the problem from image intensity function estimation perspective and assume the image contains smooth and edge components. We model the smooth components of an image using a thin-plate reproducing kernel Hilbert space (RKHS) and the edges using approximated Heaviside functions. The proposed method is applied to image patches, aiming to reduce computation and storage. Visual and quantitative comparisons with some competitive approaches show the effectiveness of the proposed method.
Real-space imaging of non-collinear antiferromagnetic order with a single-spin magnetometer
Gross, I.; Akhtar, W.; Garcia, V.; Martínez, L. J.; Chouaieb, S.; Garcia, K.; Carrétéro, C.; Barthélémy, A.; Appel, P.; Maletinsky, P.; Kim, J.-V.; Chauleau, J. Y.; Jaouen, N.; Viret, M.; Bibes, M.; Fusil, S.; Jacques, V.
2017-09-01
Although ferromagnets have many applications, their large magnetization and the resulting energy cost for switching magnetic moments bring into question their suitability for reliable low-power spintronic devices. Non-collinear antiferromagnetic systems do not suffer from this problem, and often have extra functionalities: non-collinear spin order may break space-inversion symmetry and thus allow electric-field control of magnetism, or may produce emergent spin-orbit effects that enable efficient spin-charge interconversion. To harness these traits for next-generation spintronics, the nanoscale control and imaging capabilities that are now routine for ferromagnets must be developed for antiferromagnetic systems. Here, using a non-invasive, scanning single-spin magnetometer based on a nitrogen-vacancy defect in diamond, we demonstrate real-space visualization of non-collinear antiferromagnetic order in a magnetic thin film at room temperature. We image the spin cycloid of a multiferroic bismuth ferrite (BiFeO3) thin film and extract a period of about 70 nanometres, consistent with values determined by macroscopic diffraction. In addition, we take advantage of the magnetoelectric coupling present in BiFeO3 to manipulate the cycloid propagation direction by an electric field. Besides highlighting the potential of nitrogen-vacancy magnetometry for imaging complex antiferromagnetic orders at the nanoscale, these results demonstrate how BiFeO3 can be used in the design of reconfigurable nanoscale spin textures.
Doherty, Cailbhe; Bleakley, Chris; Hertel, Jay; Caulfield, Brian; Ryan, John; Delahunt, Eamonn
2014-01-01
Instrumented postural control analysis plays an important role in evaluating the effects of injury on dynamic stability during balance tasks, and is often conveyed with measures based on the displacement of the center-of-pressure (COP) assessed with a force platform. However, the desired outcome of the task is frequently characterized by a loss of dynamic stability, secondary to injury. Typically, these failed trials are discarded during research investigations, with the potential loss of informative data pertaining to task success. The novelty of the present study is that COP characteristics of failed trials in injured participants are compared to successful trial data in another injured group, and a control group of participants, using the fractal dimension (FD) method. Three groups of participants attempted a task of eyes closed single limb stance (SLS): twenty-nine participants with acute ankle sprain successfully completed the task on their non-injured limb (successful injury group); twenty eight participants with acute ankle sprain failed their attempt on their injured limb (failed injury group); sixteen participants with no current injury successfully completed the task on their non-dominant limb (successful non-injured group). Between trial analyses of these groups revealed significant differences in COP trajectory FD (successful injury group: 1.58±0.06; failed injury group: 1.54±0.07; successful non-injured group: 1.64±0.06) with a large effect size (0.27). These findings demonstrate that successful eyes-closed SLS is characterized by a larger FD of the COP path when compared to failed trials, and that injury causes a decrease in COP path FD. Copyright © 2014 Elsevier B.V. All rights reserved.
Adaptable Single Active Loop Thermal Control System (TCS) for Future Space Missions
Mudawar, Issam; Lee, Seunghyun; Hasan, Mohammad
2015-01-01
This presentation will examine the development of a thermal control system (TCS) for future space missions utilizing a single active cooling loop. The system architecture enables the TCS to be reconfigured during the various mission phases to respond, not only to varying heat load, but to heat rejection temperature as well. The system will consist of an accumulator, pump, cold plates (evaporators), condenser radiator, and compressor, in addition to control, bypass and throttling valves. For cold environments, the heat will be rejected by radiation, during which the compressor will be bypassed, reducing the system to a simple pumped loop that, depending on heat load, can operate in either a single-phase liquid mode or two-phase mode. For warmer environments, the pump will be bypassed, enabling the TCS to operate as a heat pump. This presentation will focus on recent findings concerning two-phase flow regimes, pressure drop, and heat transfer coefficient trends in the cabin and avionics micro-channel heat exchangers when using the heat pump mode. Also discussed will be practical implications of using micro-channel evaporators for the heat pump.
Space Situational Awareness of Large Numbers of Payloads From a Single Deployment
Segerman, A.; Byers, J.; Emmert, J.; Nicholas, A.
2014-09-01
The nearly simultaneous deployment of a large number of payloads from a single vehicle presents a new challenge for space object catalog maintenance and space situational awareness (SSA). Following two cubesat deployments last November, it took five weeks to catalog the resulting 64 orbits. The upcoming Kicksat mission will present an even greater SSA challenge, with its deployment of 128 chip-sized picosats. Although all of these deployments are in short-lived orbits, future deployments will inevitably occur at higher altitudes, with a longer term threat of collision with active spacecraft. With such deployments, individual scientific payload operators require rapid precise knowledge of their satellites' locations. Following the first November launch, the cataloguing did not initially associate a payload with each orbit, leaving this to the satellite operators. For short duration missions, the time required to identify an experiment's specific orbit may easily be a large fraction of the spacecraft's lifetime. For a Kicksat-type deployment, present tracking cannot collect enough observations to catalog each small object. The current approach is to treat the chip cloud as a single catalog object. However, the cloud dissipates into multiple subclouds and, ultimately, tiny groups of untrackable chips. One response to this challenge may be to mandate installation of a transponder on each spacecraft. Directional transponder transmission detections could be used as angle observations for orbit cataloguing. Of course, such an approach would only be employable with cooperative spacecraft. In other cases, a probabilistic association approach may be useful, with the goal being to establish the probability of an element being at a given point in space. This would permit more reliable assessment of the probability of collision of active spacecraft with any cloud element. This paper surveys the cataloguing challenges presented by large scale deployments of small spacecraft
Superconducting Nanowire Single Photon Detectors for High-Data-Rate Deep-Space Optical Communication
National Aeronautics and Space Administration — High data rate deep space optical communication (DSOC) links for manned and unmanned space exploration have been identified by NASA as a critical future capability,...
Energy Technology Data Exchange (ETDEWEB)
Wadlinger, E.A.
1980-03-01
A computer program that will fit a hyperellipse to a set of phase-space points in as many as 6 dimensions was written and tested. The weight assigned to the phase-space points can be varied as a function of their distance from the centroid of the distribution. Varying the weight enables determination of whether there is a difference in ellipse orientation between inner and outer particles. This program should be useful in studying the effects of longitudinal and transverse phase-space couplings.
Dolley, T.P.
2003-01-01
Dimension stone can be defined as natural rock material quarried to obtain blocks or slabs that meet specifications as to size (width, length and thickness) and shape for architectural or engineering purposes. Color, grain texture and pattern, and surface finish of the stone are also normal requirements. Other important selection criteria are durability (based on mineral composition, hardness and past performance), strength and the ability of the stone to take a polish.
Fazio, A.; Harries, D.; Matthäus, G.; Mutschke, H.; Nolte, S.; Langenhorst, F.
2018-01-01
Space weathering is one of the most common surface process occurring on atmosphere-free bodies such as asteroids and the Moon. It is caused mainly by solar wind irradiation and the impact of micrometeoroids. In order to simulate space weathering effects, in particular those produced by hypervelocity impacts, we produced microcraters via ultra-short (∼100 fs) laser irradiation of crystallographically oriented slices of forsterite-rich (Fo94.7) olivine. The main advantages of the application of a femtosecond laser radiation to reproduce the space weathering effects are (1) the high peak irradiance (1015 W cm-2), which generates the propagation of the shock wave at the nanosecond timescale (i.e., timescale of the micrometeoroid impacts); (2) the rapid transfer of energy to the target material, which avoids the interaction of laser light with the developing vapor plume; (3) a small laser beam, which allows the effects of a single impact to be simulated. The results of our spectroscopic and electron microscopic investigation validate this approach: the samples show strong darkening and reddening of the reflectance spectra and structural damages similar to the natural microcraters found on regolith grains of the Moon and asteroid 25143 Itokawa. Detailed investigations of several microcrater cross-sections by transmission electron microscopy allowed the detection of shock-induced defect microstructures. From the top to the bottom of the grain, the shock wave causes evaporation, melting, solid-state recrystallization, misorientation, fracturing, and the propagation of dislocations with Burgers vectors parallel to [001]. The formation of a short-lived vapor plume causes the kinetic fractionation of the gas and the preferential loss of lighter elements, mostly magnesium and oxygen. The high temperatures within the melt layer and the kinetic loss of oxygen promote the thermal reduction of iron and nickel, which leads to the formation of metallic nanoparticles (npFe0). The
Spike Train SIMilarity Space (SSIMS): a frame-work for single neuron and ensemble data analysis
Vargas-Irwin, Carlos E.; Brandman, David M.; Zimmermann, Jonas B.; Donoghue, John P.; Black, Michael J.
2014-01-01
Increased emphasis on circuit level activity in the brain makes it necessary to have methods to visualize and evaluate large scale ensemble activity, beyond that revealed by raster-histograms or pairwise correlations. We present a method to evaluate the relative similarity of neural spiking patterns by combining spike train distance metrics with dimensionality reduction. Spike train distance metrics provide an estimate of similarity between activity patterns at multiple temporal resolutions. Vectors of pair-wise distances are used to represent the intrinsic relationships between multiple activity patterns at the level of single units or neuronal ensembles. Dimensionality reduction is then used to project the data into concise representations suitable for clustering analysis as well as exploratory visualization. Algorithm performance and robustness are evaluated using multielectrode ensemble activity data recorded in behaving primates. We demonstrate how Spike train SIMilarity Space (SSIMS) analysis captures the relationship between goal directions for an 8-directional reaching task and successfully segregates grasp types in a 3D grasping task in the absence of kinematic information. The algorithm enables exploration of virtually any type of neural spiking (time series) data, providing similarity-based clustering of neural activity states with minimal assumptions about potential information encoding models. PMID:25380335
Cosentino, Alberto; Mondello, Alessia; Sapia, Adalberto; D'Ottavi, Alessandro; Brotini, Mauro; Gironi, Gianna; Suetta, Enrico
2017-11-01
This paper describes energetic, spatial, temporal and spectral characterization measurements of the Engineering Qualification Model (EQM) of the Laser Transmitter Assembly (TXA) used in the ALADIN instrument currently under development for the ESA ADM-AEOLUS mission (EADS Astrium as prime contractor for the satellite and the instrument). The EQM is equivalent to the Flight Model, with the exception of some engineering grade components. The Laser Transmitter Assembly, based on a diode pumped tripled Nd:YAG laser, is used to generate laser pulses at a nominal wavelength of 355 nm. This laser is operated in burst mode, with a pulse repetition cycle of 100 Hz during bursts. It is capable to operate in Single Longitudinal Mode and to be tuned over 25 GHz range. An internal "network" of sensors has been implemented inside the laser architecture to allow "in flight" monitoring of transmitter. Energy in excess of 100 mJ, with a spatial beam quality factor (M2) lower than 3, a spectral linewidth less than 50 MHz with a frequency stability better than 4 MHz on short term period have been measured on the EQM. Most of the obtained results are well within the expected values and match the Instrument requirements. They constitute an important achievement, showing the absence of major critical areas in terms of performance and the capability to obtain them in a rugged and compact structure suitable for space applications. The EQM will be submitted in the near future to an Environmental test campaign.
Vossos, Spyridon; Vossos, Elias
2016-08-01
closed LSTT is reduced, if one RIO has small velocity wrt another RIO. Thus, we have infinite number of closed LSTTs, each one with the corresponding SR theory. In case that we relate accelerated observers with variable metric of spacetime, we have the case of General Relativity (GR). For being that clear, we produce a generalized Schwarzschild metric, which is in accordance with any SR based on this closed complex LSTT and Einstein equations. The application of this kind of transformations to the SR and GR is obvious. But, the results may be applied to any linear space of dimension four endowed with steady or variable metric, whose elements (four- vectors) have spatial part (vector) with Euclidean metric.
International Nuclear Information System (INIS)
Vossos, Spyridon; Vossos, Elias
2016-01-01
any other closed LSTT is reduced, if one RIO has small velocity wrt another RIO. Thus, we have infinite number of closed LSTTs, each one with the corresponding SR theory. In case that we relate accelerated observers with variable metric of spacetime, we have the case of General Relativity (GR). For being that clear, we produce a generalized Schwarzschild metric, which is in accordance with any SR based on this closed complex LSTT and Einstein equations. The application of this kind of transformations to the SR and GR is obvious. But, the results may be applied to any linear space of dimension four endowed with steady or variable metric, whose elements (four- vectors) have spatial part (vector) with Euclidean metric. (paper)
Single-Mode, High Repetition Rate, Compact Ho:YLF Laser for Space-Borne Lidar Applications
Bai, Yingxin; Yu, Jirong; Wong, Teh-Hwa; Chen, Songsheng; Petros, Mulugeta; Singh, Upendra N.
2014-01-01
A single transverse/longitudinal mode, compact Q-switched Ho:YLF laser has been designed and demonstrated for space-borne lidar applications. The pulse energy is between 34-40 mJ for 100-200 Hz operation. The corresponding peak power is >1 MW.
Space Vector Pulse Width Modulation Strategy for Single-Phase Three-Level CIC T-source Inverter
DEFF Research Database (Denmark)
Shults, Tatiana E.; Husev, Oleksandr O.; Blaabjerg, Frede
2016-01-01
This paper presents a novel space vector pulse-width modulation strategy for a single-phase three-level buck-boost inverter based on an impedance-source network. The case study system is based on T-source inverter with continuous input current. To demonstrate the improved performance of the inver...
DEFF Research Database (Denmark)
Lu, Yong; Xiao, Guochun; Wang, Xiongfei
2016-01-01
The unified power quality conditioner (UPQC) is known as an effective compensation device to improve PQ for sensitive end-users. This paper investigates the operation and control of a single-phase three-leg UPQC (TL-UPQC), where a novel space vector modulation method is proposed for naturally...... solving the coupling problem introduced by the common switching leg. The modulation method is similar to the well-known space vector modulation widely used with three-phase voltage source converters, which thus brings extra flexibility to the TL-UPQC system. Two optimized modulation modes with either...... reduced switching loss or harmonic distortion are derived, evaluated, and discussed, in order to demonstrate the flexibility brought by the space vector modulated TL-UPQC. Simulations and experimental results are presented to verify the feasibility and effectiveness of the proposed space vector modulation...
Why do we live in 3+1 dimensions?
International Nuclear Information System (INIS)
Nielsen, H.B.; Rugh, S.E.
1993-01-01
Noticing that really the fermions of the Standard Model are best thought of a Weyl - rather than Dirac - particles (relative to fundamental scales located at some presumably very high energies) it becomes interesting that the experimental space-time dimension is singled out by the Weyl equation: It is observed that precisely in the experimentally true space-time dimensionality 4=3+1 the number of linearly independent matrices n 2 Weyl dimensionized as the matrices in the Weyl equation equals the dimension d. So just in this dimension (in fact, also in a trivial case d = 1) do the sigma-matrices of the Weyl-equation form a basis. It is also characteristic for this dimension that there is no degeneracy of helicity states of the Weyl spinor for all nonzero momenta. We would like to interpret these features to signal a special 'form stability' of the Weyl equation in the phenomenologically true dimension of space-time. In an attempt of making this stability to occur in an as large as possible basin of allowed modifications we discuss whether it is possible to define what we could possibly mean by 'stability of Natural laws'. (orig.)
High core count single-mode multicore fiber for dense space division multiplexing
DEFF Research Database (Denmark)
Aikawa, K.; Sasaki, Y.; Amma, Y.
2016-01-01
Multicore fibers and few-mode fibers have the potential to realize dense-space-division multiplexing systems. Several dense-space-division multiplexing system transmission experiments over multicore fibers and few-mode fibers have been demonstrated so far. Multicore fibers, including recent resul...
2013-01-01
A few weeks ago, I had a vague notion of what TED was, and how it worked, but now I’m a confirmed fan. It was my privilege to host CERN’s first TEDx event last Friday, and I can honestly say that I can’t remember a time when I was exposed to so much brilliance in such a short time. TEDxCERN was designed to give a platform to science. That’s why we called it Multiplying Dimensions – a nod towards the work we do here, while pointing to the broader importance of science in society. We had talks ranging from the most subtle pondering on the nature of consciousness to an eighteen year old researcher urging us to be patient, and to learn from our mistakes. We had musical interludes that included encounters between the choirs of local schools and will.i.am, between an Israeli pianist and an Iranian percussionist, and between Grand Opera and high humour. And although I opened the event by announcing it as a day off from physics, we had a quite brill...
GHOLAMI, SAEID; BABOLIAN, ESMAIL; JAVIDI, MOHAMMAD
2016-01-01
This paper presents a new numerical approach to solve single and multiterm time fractional diffusion equations. In this work, the space dimension is discretized to the Gauss$-$Lobatto points. We use the normalized Grunwald approximation for the time dimension and a pseudospectral successive integration matrix for the space dimension. This approach shows that with fewer numbers of points, we can approximate the solution with more accuracy. Some examples with numerical results in tables and fig...
The search for extra dimensions
International Nuclear Information System (INIS)
Abel, Steven; March-Russell, John
2000-01-01
The possibility of extra dimensions, beyond the three dimensions of space of our everyday experience, sometimes crops up as a convenient, if rather vague, plot in science fiction. In science, however, the idea of extra dimensions has a rich history, dating back at least as far as the 1920s. Recently there has been a remarkable renaissance in this area due to the work of a number of theoretical physicists. It now seems possible that we, the Earth and, indeed, the entire visible universe are stuck on a membrane in a higher-dimensional space, like dust particles that are trapped on a soap bubble. In this article the authors look at the major issues behind this new development. Why, for example, don't we see these extra dimensions? If they exist, how can we detect them? And perhaps the trickiest question of all: how did this fanciful idea come to be considered in the first place? (U.K.)
Origin of Everything and the 21 Dimensions of the Universe
Loev, Mark
2009-03-01
The Dimensions of the Universe correspond with the Dimensions of the human body. The emotion that is a positive for every dimension is Love. The negative emotion that effects each dimension are listed. All seven negative emotions effect Peace, Love and Happiness. 21st Dimension: Happiness Groin & Heart 20th Dimension: Love Groin & Heart 19th Dimension: Peace Groin & heart 18th Dimension: Imagination Wave Eyes Anger 17th Dimension: Z Wave / Closed Birth 16th Dimension: Electromagnetic Wave Ears Anger 15th Dimension: Universal Wave Skin Worry 14th Dimension: Lover Wave Blood Hate 13th Dimension: Disposal Wave Buttocks Fear 12th Dimension: Builder Wave Hands Hate 11th Dimension: Energy Wave Arms Fear 10th Dimension: Time Wave Brain Pessimism 9th Dimension: Gravity Wave Legs Fear 8th Dimension: Sweet Wave Pancreas Fear 7th Dimension: File Wave Left Lung Fear 6th Dimension: Breathing Wave Right Lung Fear 5th Dimension: Digestive Wave Stomach Fear 4th Dimension: Swab Wave Liver Guilt 3rd Dimension: Space Wave Face Sadness 2nd Dimension: Line Wave Mouth Revenge 1st Dimension: Dot Wave Nose Sadness The seven deadly sins correspond: Anger Hate Sadness Fear Worry Pessimism Revenge Note: Guilt is fear
Experimental single photon exchange along a space link of 7000 km
DEFF Research Database (Denmark)
Dequal, Daniele; Vallone, Giuseppe; Bacco, Davide
2015-01-01
at the Matera Laser Ranging Observatory. The single photon transmitter was realized by exploiting the corner cube retro-reflectors mounted on the LAGEOS-2 satellite. Long duration of data collection is possible with such altitude, up to 43 minutes in a single passage. The mean number of photons per pulse (µsat...
Sealing efficacy of a single-cone root filling after post space preparation
Sungur, D.D.; Moinzadeh, A.T.; Wesselink, P.R.; Tarhan, S.C.; Özok, A.R.
2016-01-01
Objectives The aim of the present study was to compare the sealing efficacy of root fillings made by a single-cone technique with three different sealers and a cold lateral compaction technique with an epoxy sealer. Materials and methods Eighty extracted single-rooted human teeth were assigned to
Chen, Yao-Xuan; Ge, Qian-Qing; Shi, Yang; Liu, Jie; Xue, Ding-Jiang; Ma, Jing-Yuan; Ding, Jie; Yan, Hui-Juan; Hu, Jin-Song; Wan, Li-Jun
2016-12-21
Organic-inorganic hybrid perovskite single-crystalline thin films (SCTFs) are promising for enhancing photoelectric device performance due to high carrier mobility, long diffusion length, and carrier lifetime. However, bulk perovskite single crystals available today are not suitable for practical device application due to the unfavorable thickness. Herein, we report a facile space-confined solution-processed strategy to on-substrate grow various hybrid perovskite SCTFs in a size of submillimeter with adjustable thicknesses from nano- to micrometers. These SCTFs exhibit photoelectric properties comparable to bulk single crystals with low defect density and good air stability. The clear thickness-dependent colors allow fast visual selection of SCTFs with a suitable thickness for specific device application. The present substrate-independent growth of perovskite SCTFs opens up opportunities for on-chip fabrication of diverse high-performance devices.
From Single Atoms to Engineered “Super-Atoms”: Interfacing Photons and Atoms in Free Space
Directory of Open Access Journals (Sweden)
Yevhen Miroshnychenko
2014-01-01
Full Text Available During the last decades the development of laser cooling and trapping has revolutionized the field of quantum optics. Now we master techniques to control the quantum properties of atoms and light, even at a single atom and single photon level. Understanding and controlling interactions of atoms and light both on the microscopic single particle and on the macroscopic collective levels, are two of the very active directions of the current research in this field. The goal is to engineer quantum systems with tailored properties designed for specific applications. One of the ambitious applications on this way is interfacing quantum information for quantum communication and quantum computing. We summarize here theoretical ideas and experimental methods for interfacing atom-based quantum memories with single flying photons.
On Gorenstein projective, injective and flat dimensions
DEFF Research Database (Denmark)
Christensen, Lars Winther; Frankild, Anders Juel; Holm, Henrik Granau
2006-01-01
Gorenstein homological dimensions are refinements of the classical homological dimensions, and finiteness singles out modules with amenable properties reflecting those of modules over Gorenstein rings. As opposed to their classical counterparts, these dimensions do not immediately come...... with practical and robust criteria for finiteness, not even over commutative noetherian local rings. In this paper we enlarge the class of rings known to admit good criteria for finiteness of Gorenstein dimensions:...
Label Space Reduction in MPLS Networks: How Much Can A Single Stacked Label Do?
DEFF Research Database (Denmark)
Solano, Fernando; Stidsen, Thomas K.; Fabregat, Ramon
2008-01-01
Most network operators have considered reducing LSR label spaces (number of labels used) as a way of simplifying management of underlaying virtual private networks (VPNs) and therefore reducing operational expenditure (OPEX). The IETF outlined the label merging feature in MPLS-allowing the config......Most network operators have considered reducing LSR label spaces (number of labels used) as a way of simplifying management of underlaying virtual private networks (VPNs) and therefore reducing operational expenditure (OPEX). The IETF outlined the label merging feature in MPLS...
Quantum scattering theory of a single-photon Fock state in three-dimensional spaces.
Liu, Jingfeng; Zhou, Ming; Yu, Zongfu
2016-09-15
A quantum scattering theory is developed for Fock states scattered by two-level systems in three-dimensional free space. It is built upon the one-dimensional scattering theory developed in waveguide quantum electrodynamics. The theory fully quantizes the incident light as Fock states and uses a non-perturbative method to calculate the scattering matrix.
Single event effects and performance predictions for space applications of RISC processors
Energy Technology Data Exchange (ETDEWEB)
Kimbrough, J.R.; Colella, N.J.; Denton, S.M.; Shaeffer, D.L.; Shih, D.; Wilburn, J.W. (Lawrence Livermore National Lab., CA (United States)); Coakley, P.G. (JAYCOR, San Diego, CA (United States)); Casteneda, C. (Crocker Nuclar Lab., Davis, CA (United States)); Koga, R. (Aerospace Corp., El Segundo, CA (United States)); Clark, D.A.; Ullmann, J.L. (Los Alamos National Lab., NM (United States))
1994-12-01
Proton and ion Single Event Phenomena (SEP) tests were performed on 32-b processors including R3000A's from all commercial manufacturers along with the Performance PR3400 family, Integrated Device Technology Inc. 79R3081, LSI Logic Corporation LR33000HC, and Intel i80960MX parts. The microprocessors had acceptable upset rates for operation in a low earth orbit or a lunar mission such as CLEMENTINE with a wide range in proton total dose failure. Even though R3000A devices are 60% smaller in physical area than R3000 devices, there was a 340% increase in device Single Event Upset (SEU) cross section. Software tests of varying complexity demonstrate that registers and other functional blocks using register architecture dominate the cross section. The current approach of giving a single upset cross section can lead to erroneous upset rates depending on the application software.
Conceptualising Curricular Space in Busyness Education
DEFF Research Database (Denmark)
Blasco, Maribel
2016-01-01
. Space is conceived in terms of three dimensions that may either be produced or foreclosed by curricular structures and content: time-space dimension, autonomy dimension, reflective dimension and cognitive dimension. Together, these spaces enable imaginative space, which is important for innovative...
Single Step to Orbit; a First Step in a Cooperative Space Exploration Initiative
Lusignan, Bruce; Sivalingam, Shivan
1999-01-01
At the end of the Cold War, disarmament planners included a recommendation to ease reduction of the U.S. and Russian aerospace industries by creating cooperative scientific pursuits. The idea was not new, having earlier been suggested by Eisenhower and Khrushchev to reduce the pressure of the "Military Industrial Complex" by undertaking joint space exploration. The Space Exploration Initiative (SEI) proposed at the end of the Cold War by President Bush and Premier Gorbachev was another attempt to ease the disarmament process by giving the bloated war industries something better to do. The engineering talent and the space rockets could be used for peaceful pursuits, notably for going back to the Moon and then on to Mars with human exploration and settlement. At the beginning of this process in 1992 staff of the Stanford Center for International Cooperation in Space attended the International Space University in Canada, met with Russian participants and invited a Russian team to work with us on a joint Stanford-Russian Mars Exploration Study. A CIA student and Airforce and Navy students just happened to join the Stanford course the next year and all students were aware that the leader of the four Russian engineers was well versed in Russian security. But, as long as they did their homework, they were welcome to participate with other students in defining the Mars mission and the three engineers they sent were excellent. At the end of this study we were invited to give a briefing to Dr. Edward Teller at Stanford's Hoover Institution of War and Peace. We were also encouraged to hold a press conference on Capitol Hill to introduce the study to the world. At a pre-conference briefing at the Space Council, we were asked to please remind the press that President Bush had asked for a cooperative exploration proposal not a U.S. alone initiative. The Stanford-Russian study used Russia's Energia launchers, priced at $300 Million each. The mission totaled out to $71.5 Billion
International Nuclear Information System (INIS)
Hoekmark, Harald; Faelth, Billy
2003-12-01
The report addresses the problem of the minimum spacing required between neighbouring canisters in the deep repository. That spacing is calculated for a number of assumptions regarding the conditions that govern the temperature in the nearfield and at the surfaces of the canisters. The spacing criterion is that the temperature at the canister surfaces must not exceed 100 deg C .The results are given in the form of nomographic charts, such that it is in principle possible to determine the spacing as soon as site data, i.e. the initial undisturbed rock temperature and the host rock heat transport properties, are available. Results of canister spacing calculations are given for the KBS-3V concept as well as for the KBS-3H concept. A combination of numerical and analytical methods is used for the KBS-3H calculations, while the KBS-3V calculations are purely analytical. Both methods are described in detail. Open gaps are assigned equivalent heat conductivities, calculated such that the conduction across the gaps will include also the heat transferred by radiation. The equivalent heat conductivities are based on the emissivities of the different gap surfaces. For the canister copper surface, the emissivity is determined by back-calculation of temperatures measured in the Prototype experiment at Aespoe HRL. The size of the different gaps and the emissivity values are of great importance for the results and will be investigated further in the future
Energy Technology Data Exchange (ETDEWEB)
Kotasidis, F A; Matthews, J C; Angelis, G I; Noonan, P J; Jackson, A [Imaging, Genomics and Proteomics, Wolfson Molecular Imaging Centre, MAHSC, University of Manchester, Manchester (United Kingdom); Price, P [Academic Department of Radiation Oncology, University of Manchester, Manchester (United Kingdom); Lionheart, W R [School of Mathematics, Alan Turing Building, University of Manchester, Manchester (United Kingdom); Reader, A J, E-mail: fotis.kotasidis@mmic.man.ac.uk [Brain Imaging Centre, Montreal Neurological Institute, McGill University, Montreal, QC (Canada)
2011-05-21
Incorporation of a resolution model during statistical image reconstruction often produces images of improved resolution and signal-to-noise ratio. A novel and practical methodology to rapidly and accurately determine the overall emission and detection blurring component of the system matrix using a printed point source array within a custom-made Perspex phantom is presented. The array was scanned at different positions and orientations within the field of view (FOV) to examine the feasibility of extrapolating the measured point source blurring to other locations in the FOV and the robustness of measurements from a single point source array scan. We measured the spatially-variant image-based blurring on two PET/CT scanners, the B-Hi-Rez and the TruePoint TrueV. These measured spatially-variant kernels and the spatially-invariant kernel at the FOV centre were then incorporated within an ordinary Poisson ordered subset expectation maximization (OP-OSEM) algorithm and compared to the manufacturer's implementation using projection space resolution modelling (RM). Comparisons were based on a point source array, the NEMA IEC image quality phantom, the Cologne resolution phantom and two clinical studies (carbon-11 labelled anti-sense oligonucleotide [{sup 11}C]-ASO and fluorine-18 labelled fluoro-l-thymidine [{sup 18}F]-FLT). Robust and accurate measurements of spatially-variant image blurring were successfully obtained from a single scan. Spatially-variant resolution modelling resulted in notable resolution improvements away from the centre of the FOV. Comparison between spatially-variant image-space methods and the projection-space approach (the first such report, using a range of studies) demonstrated very similar performance with our image-based implementation producing slightly better contrast recovery (CR) for the same level of image roughness (IR). These results demonstrate that image-based resolution modelling within reconstruction is a valid alternative to
Variable dose rate single-arc IMAT delivered with a constant dose rate and variable angular spacing
International Nuclear Information System (INIS)
Tang, Grace; Earl, Matthew A; Yu, Cedric X
2009-01-01
Single-arc intensity-modulated arc therapy (IMAT) has gained worldwide interest in both research and clinical implementation due to its superior plan quality and delivery efficiency. Single-arc IMAT techniques such as the Varian RapidArc(TM) deliver conformal dose distributions to the target in one single gantry rotation, resulting in a delivery time in the order of 2 min. The segments in these techniques are evenly distributed within an arc and are allowed to have different monitor unit (MU) weightings. Therefore, a variable dose-rate (VDR) is required for delivery. Because the VDR requirement complicates the control hardware and software of the linear accelerators (linacs) and prevents most existing linacs from delivering IMAT, we propose an alternative planning approach for IMAT using constant dose-rate (CDR) delivery with variable angular spacing. We prove the equivalence by converting VDR-optimized RapidArc plans to CDR plans, where the evenly spaced beams in the VDR plan are redistributed to uneven spacing such that the segments with larger MU weighting occupy a greater angular interval. To minimize perturbation in the optimized dose distribution, the angular deviation of the segments was restricted to ≤± 5 deg. This restriction requires the treatment arc to be broken into multiple sectors such that the local MU fluctuation within each sector is reduced, thereby lowering the angular deviation of the segments during redistribution. The converted CDR plans were delivered with a single gantry sweep as in the VDR plans but each sector was delivered with a different value of CDR. For four patient cases, including two head-and-neck, one brain and one prostate, all CDR plans developed with the variable spacing scheme produced similar dose distributions to the original VDR plans. For plans with complex angular MU distributions, the number of sectors increased up to four in the CDR plans in order to maintain the original plan quality. Since each sector was
Noori, Parisa; Najafpour Darzi, Ghasem
2016-05-01
Development and practical application of microbial fuel cell (MFC) is restricted because of the limitations such as low power output. To overcome low power limitation, the optimization of specific parameters including electrode materials and surface area, electrode spacing, and MFC's cell shape was investigated. To the best of our knowledge, no investigation has been reported in the literature to implement an annular single-chamber microbial fuel cell (ASCMFC) using chocolate industry wastewater. ASCMFC was fabricated via optimization of the stated parameters. The aspects of ASCMFC were comprehensively examined. In this study, the optimization of electrode spacing and its impact on performance of the ASCMFC were conducted. Reduction of electrode spacing by 46.15% (1.3-0.7 cm) resulted in a decrease in internal resistance from 100 to 50 Ω, which enhanced the power density and current output to 22.898 W/m(3) and 6.42 mA, respectively. An optimum electrode spacing of 0.7 cm was determined. Through this paper, the effects of these parameters and the performance of ASCMFC are also evaluated. © 2015 International Union of Biochemistry and Molecular Biology, Inc.
Someya, Hiroshi; Yamamura, Masayuki; Sakamoto, Kensaku
This paper discusses DNA-based stochastic optimizations under the constraint that the search starts from a given point in a search space. Generally speaking, a stochastic optimization method explores a search space and finds out the optimum or a sub-optimum after many cycles of trials and errors. This search process could be implemented efficiently by ``molecular computing'', which processes DNA molecules by the techniques of molecular biology to generate and evaluate a vast number of solution candidates at a time. We assume the exploration starting from a single point, and propose a method to embody DNA-based optimization under this constraint, because this method has a promising application in the research field of protein engineering. In this application, a string of nucleotide bases (a base sequence) encodes a protein possessing a specific activity, which could be given as a value of an objective function. Thus, a problem of obtaining a protein with the optimum or a sub-optimum about the desired activity corresponds to a combinatorial problem of obtaining a base sequence giving the optimum or a sub-optimum in the sequence space. Biologists usually modify a base sequence corresponding to a naturally occurring protein into another sequence giving a desired activity. In other words, they explore the space in the proximity of a natural protein as a start point. We first examined if the optimization methods that involve a single start point, such as simulated annealing, Gibbs sampler, and MH algorithms, can be implemented by DNA-based operations. Then, we proposed an application of genetic algorithm, and examined the performance of this application on a model fitness landscape by computer experiments. These experiments gave helpful guidelines in the embodiments of DNA-based stochastic optimization, including a better design of crossover operator.
Guo, Yan; Zhao, Bo; Yang, Jianjun
2013-06-17
We theoretically demonstrate that a single bare subwavelength metal slit without any surrounding corrugations can have a capability to steer the incident light into focusing patterns by introducing a high index in the transmission half-space. The focusing properties are identified to depend on both the slit width and the output permittivity. The underlying physics lies in the interference of quasi-cylindrical waves scattered from the slit, and our proposed model agrees well with the simulation results. This finding is believed to inspire some novel ideas for the nano-optics design.
Flow tests of a single fuel element coolant channel for a compact fast reactor for space power
Springborn, R. H.
1971-01-01
Water flow tests were conducted on a single-fuel-element cooling channel for a nuclear concept to be used for space power. The tests established a method for measuring coolant flow rate which is applicable to water flow testing of a complete mockup of the reference reactor. The inlet plenum-to-outlet plenum pressure drop, which approximates the overall core pressure drop, was measured and correlated with flow rate. This information can be used for reactor coolant flow and heat transfer calculations. An analytical study of the flow characteristics was also conducted.
Daiya, D.; Patidar, R. K.; Sharma, J.; Joshi, A. S.; Naik, P. A.; Gupta, P. D.
2017-04-01
A new optical design of tiled single grating pulse compressor has been proposed, set-up and studied. The parametric space, i.e. the laser beam diameters that can be accommodated in the pulse compressor for the given range of compression lengths, has been calculated and shown to have up to two fold enhancement in comparison to our earlier proposed optical designs. The new optical design of the tiled single grating pulse compressor has an additional advantage of self compensation of various tiling errors like longitudinal and lateral piston, tip and groove density mismatch, compared to the earlier designs. Experiments have been carried out for temporal compression of 650 ps positively chirped laser pulses, at central wavelength 1054 nm, down to 235 fs in the tiled grating pulse compressor set up with the proposed design. Further, far field studies have been performed to show the desired compensation of the tiling errors takes place in the new compressor.
Neutrino oscillations in deconstructed dimensions
International Nuclear Information System (INIS)
Haellgren, Tomas; Ohlsson, Tommy; Seidl, Gerhart
2005-01-01
We present a model for neutrino oscillations in the presence of a deconstructed non-gravitational large extra dimension compactified on the boundary of a two-dimensional disk. In the deconstructed phase, sub-mm lattice spacings are generated from the hierarchy of energy scales between ∼ 1 TeV and the usual B-L breaking scale ∼ 10 15 GeV. Here, short-distance cutoffs down to ∼ 1 eV are motivated by the strong coupling behavior of gravity in local discrete extra dimensions. This could make it possible to probe the discretization of extra dimensions and non-trivial field configurations in theory spaces which have only a few sites, i.e., for coarse latticizations. Thus, the model has relevance to present and future precision neutrino oscillation experiments. (author)
Complete sets of cyclic mutually unbiased bases in even prime-power dimensions
Energy Technology Data Exchange (ETDEWEB)
Kern, Oliver; Ranade, Kedar S; Seyfarth, Ulrich, E-mail: oliver.kern@physik.tu-darmstadt.d [Institut fuer Angewandte Physik, Technische Universitaet Darmstadt, 64289 Darmstadt (Germany)
2010-07-09
We present a construction method for complete sets of cyclic mutually unbiased bases (MUBs) in Hilbert spaces of even prime-power dimensions. In comparison to the usual complete sets of MUBs, complete cyclic sets possess the additional property of being generated by a single unitary operator. The construction method is based on the idea of obtaining a partition of multi-qubit Pauli operators into maximal commuting sets of operators with the help of a suitable element of the Clifford group. As a consequence, we explicitly obtain complete sets of cyclic MUBs generated by a single element of the Clifford group in dimensions 2{sup m} for m = 1, 2, ..., 24.
Energy Technology Data Exchange (ETDEWEB)
Tawfik, Ahmed M., E-mail: ahm_m_tawfik@hotmail.com [Institut für Diagnostische und Interventionelle Radiologie, Klinikum der J.W.v. Goethe Universität Frankfurt am Main, Theodor-Stern-Kai 7 Frankfurt am Main 60590 (Germany); Diagnostic Radiology Department, Mansoura Faculty of Medicine, 62 Elgomhorya Street, Mansoura 35512 (Egypt); Nour-Eldin, Nour-Eldin A.; Naguib, Nagy N. [Institut für Diagnostische und Interventionelle Radiologie, Klinikum der J.W.v. Goethe Universität Frankfurt am Main, Theodor-Stern-Kai 7 Frankfurt am Main 60590 (Germany); Razek, Ahmed Abdel [Diagnostic Radiology Department, Mansoura Faculty of Medicine, 62 Elgomhorya Street, Mansoura 35512 (Egypt); Denewer, Adel T. [Surgical Oncology Department, Mansoura Oncology Centre, Mansoura Faculty of medicine (Egypt); Bisdas, Sotirios [Department of Neuroradiology, Eberhard Karls University, Tübingen (Germany); Vogl, Thomas J. [Institut für Diagnostische und Interventionelle Radiologie, Klinikum der J.W.v. Goethe Universität Frankfurt am Main, Theodor-Stern-Kai 7 Frankfurt am Main 60590 (Germany)
2012-10-15
Purpose: To evaluate the agreement between quantitative CT perfusion measurements of head and neck squamous cell carcinoma (SCC) obtained from single section with maximal tumor dimension and from average values of multiple sections, and to compare intra- and inter-observer agreement of the two methods. Methods: Perfusion was measured for 28 SCC cases using a region of interest (ROI) inserted in the single dynamic CT section showing maximal tumor dimension, then using average values of multiple ROIs inserted in all tumor-containing sections. Agreement between values of blood flow (BF), blood volume (BV), mean transit time (MTT) and permeability surface area product (PS) calculated by the two methods was assessed. Intra-observer agreement was assessed by comparing repeated calculations done by the same radiologist using both methods after 2 months blinding period. Perfusion measurements were done by another radiologist independently to assess inter-observer agreement of both methods. Results: No significant differences were observed between the means of the 4 perfusion parameters calculated by both methods, all p values >0.05 The 95% limits of agreement between the two methods were (−33.9 to 43) ml/min/100 g for BF, (−2.5 to 2.8) ml/100 g for BV, (−4.9 to 3.9) s for MTT and (−17.5 to 18.6) ml/min/100 g for PS. Narrower limits of agreement were obtained using average of multiple sections than with single section denoting improved intra- and inter-observer agreement. Conclusion: Agreement between both methods is acceptable. Taking the average of multiple sections slightly improves intra- and inter-observer agreement.
Variations of QED in three dimensions
International Nuclear Information System (INIS)
Fronsdal, C.
1991-01-01
The quantization of three-dimensional electrodynamics in 2 + 2 De Sitter space is carried out in detail. In three dimensions the author finds completely different types of quantum electrodynamics. The most interesting versions have spins +1 and/or -1. When both spins are combined as modes of a single vector potential with definite parity, then the field strength vanishes; nevertheless the theory has an infinite space of propagating physical modes. This version of three-dimensional QED is equivalent to three-dimensional singleton theory. The requirements of gauge invariance prohibit local interactions, in the classical theory and within the framework of canonical quantization, and interactions are thus limited to the boundary at spatial infinity, a torus. There are also two chiral theories, in which the physical modes have spin +1 only, or -1 only; here the field strength is not identically zero, though it vanishes on the physical subspace. The chiral theories do not have smooth limits as the curvature tends to zero. All these versions of electrodynamics are smooth limits as the curvature tends to zero. All these versions of electrodynamics are smooth limits of massive vector theories, and all can be regarded as quantized counterparts of classical Chern-Simons theory. The most standard form of three-dimensional QED has physical modes with spin zero; it is in a sense a limit of a massive theory with spin zero. In two dimensions the only physical degree of freedom is an excitation with vanishing energy and momentum, a topological mode
Effect of occlusal vertical dimension on lip positions at smile.
Chou, Jang-Ching; Thompson, Geoffrey A; Aggarwal, Harshit A; Bosio, Jose A; Irelan, Jon P
2014-09-01
In complete mouth reconstructive dentistry, the occlusal vertical dimension may be increased to provide adequate restorative space or to improve esthetics. The effect of increasing the occlusal vertical dimension on the smile is not well understood. The purpose of this study was to evaluate the effect of increasing the occlusal vertical dimension on the dimensions of the smile. Thirty dental students, 12 men and 18 women between the ages of 21 and 30 years old, participated in this study. Polyvinyl siloxane occlusal registrations 2, 4, 6, and 8 mm in thickness were fabricated from articulated stone casts. Posed smile images at occlusal vertical dimension +0, +2, +4, +6, and +8 mm were made with a digital single lens reflex camera mounted on a tripod. A wall-mounted head-positioning device, modified from a cephalometric unit, was used to stabilize the head position. Interlabial gap height, intercommissural width, incisal edge to upper lip, and incisal edge-to-lower lip measurements were made with computer software. The smile index was obtained by dividing width by height. The display zone area was measured by using computer software tracing. One-way repeated measures ANOVA (α=.05) was used for statistical analysis. With an increase in the occlusal vertical dimension, the interlabial gap height, incisal edge to lower lip distance, and display zone area increased significantly (Pocclusal vertical dimension. The smile index decreases with increased occlusal vertical dimension. However, the width of the smile and the length of the upper lip tend to remain unchanged. Copyright © 2014 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.
Berg, Melanie; Label, Kenneth; Campola, Michael; Xapsos, Michael
2017-01-01
We propose a method for the application of single event upset (SEU) data towards the analysis of complex systems using transformed reliability models (from the time domain to the particle fluence domain) and space environment data.
Berg, Melanie; Label, Kenneth; Campola, Michael; Xapsos, Michael
2017-01-01
We propose a method for the application of single event upset (SEU) data towards the analysis of complex systems using transformed reliability models (from the time domain to the particle fluence domain) and space environment data.
Single- and dual-carrier microwave noise abatement in the deep space network. [microwave antennas
Bathker, D. A.; Brown, D. W.; Petty, S. M.
1975-01-01
The NASA/JPL Deep Space Network (DSN) microwave ground antenna systems are presented which simultaneously uplink very high power S-band signals while receiving very low level S- and X-band downlinks. Tertiary mechanisms associated with elements give rise to self-interference in the forms of broadband noise burst and coherent intermodulation products. A long-term program to reduce or eliminate both forms of interference is described in detail. Two DSN antennas were subjected to extensive interference testing and practical cleanup program; the initial performance, modification details, and final performance achieved at several planned stages are discussed. Test equipment and field procedures found useful in locating interference sources are discussed. Practices deemed necessary for interference-free operations in the DSN are described. Much of the specific information given is expected to be easily generalized for application in a variety of similar installations. Recommendations for future investigations and individual element design are given.
High-efficiency 3 W/40 K single-stage pulse tube cryocooler for space application
Zhang, Ankuo; Wu, Yinong; Liu, Shaoshuai; Liu, Biqiang; Yang, Baoyu
2018-03-01
Temperature is an extremely important parameter for space-borne infrared detectors. To develop a quantum-well infrared photodetector (QWIP), a high-efficiency Stirling-type pulse tube cryocooler (PTC) has been designed, manufactured and experimentally investigated for providing a large cooling power at 40 K cold temperature. Simulated and experimental studies were carried out to analyse the effects of low temperature on different energy flows and losses, and the performance of the PTC was improved by optimizing components and parameters such as regenerator and operating frequency. A no-load lowest temperature of 26.2 K could be reached at a frequency of 51 Hz, and the PTC could efficiently offer cooling power of 3 W at 40 K cold temperature when the input power was 225 W. The efficiency relative to the Carnot efficiency was approximately 8.4%.
Tominaga, Jun-ya; Ozaki, Hiroya; Chiang, Pao-Chang; Sumi, Mayumi; Tanaka, Motohiro; Koga, Yoshiyuki; Bourauel, Christoph; Yoshida, Noriaki
2014-08-01
It has been found that controlled movement of the anterior teeth can be obtained by attaching a certain length of power arm onto an archwire in sliding mechanics. However, the impact of the archwire/bracket play on anterior tooth movement has not been clarified. The purpose of this study was to compare the effect of the power arm on anterior tooth movements with different dimensions of bracket slots and archwires. A 3-dimensional finite element method was used to simulate en-masse anterior tooth retraction in sliding mechanics. Displacements of the maxillary central incisor and the archwire deformation were calculated when applying retraction forces from different lengths of power arms. When a 0.017 × 0.022-in archwire was engaged into the 0.018-in slot bracket, bodily movement of the incisor was obtained with 9.1-mm length of the power arm. When a 0.022-in slot system was coupled with a 0.019 × 0.025-in archwire, bodily movement was observed with a power arm length of 11.6 mm. Archwire/bracket play has a remarkable impact on anterior tooth movement. An effective torque application to the anterior teeth becomes clinically difficult in sliding mechanics combined with power arms when the archwire/bracket play is large. Copyright © 2014 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.
Directory of Open Access Journals (Sweden)
Liina Unt
2014-12-01
Full Text Available The comparison between theatre and playing has spread on many levels, from metaphors to sayings, aesthetic concepts to deterministic models. This paper examines scenography as an active play environment. Play, in the context of theatre space, is defined according to the classical characteristic features of playing: spatial and temporal limits, fictionality that runs in parallel with everyday reality, and direct involvement. The paper focuses on the specific aspects of play environment as it appears in the Tartu New Theatre’s performances of „The Death of the Author“ and „The Beatles of Vanemuine“. Both productions are set in fictional locations with a visually static set design. Both are unique in that different locations are created without changing the physical space on stage – places appear and disappear through the performances, created by an odd textual allusion or two, or the audience’s imagination. The changes can be understood through the audience’s corporal perception, which this paper interprets using Merleau-Ponty’s phenomenological concept of corporeity. Using Tartu New Theatre’s stage practice and Hans-Georg Gadamer’s hermeneutic aesthetics, the paper aims to answer the question: what is the aesthetic structure of such stage environments and how can an environmental experience be created, if the direct interference in space is minimal. Gadamer’s aesthetic concept revolves around play, interpreting works of art as a structure, a meaningful whole that can be presented and comprehended repeatedly. However, he qualifies that the structure, itself, is also a play as, despite a theoretic unity, it only exists when it is played. In this case, the scenography becomes an environment with open meanings, where attributing meaning and function happens through the agreements made during the act of playing, which don’t necessarily also imply physical changes to the environment. The environment is an agreed-upon space
Space and Motion Stimulus-Response Correspondence (SRC) Effects in a Single Task.
Styrkowiec, Piotr
2016-09-01
Previous research indicated that congruency between stimulus location and response position (spatial stimulus-response correspondence [SRC]) and stimulus motion and response movement congruency (motion SRC) are distinct SRC phenomena. This study further explored this issue and tested whether these two SRC effects are independent. This was conducted by investigating these two SRC effects in a single task. A stimulus with leftward or rightward motion was presented on the left or the right side of the screen and the participant had to move the joysticks held with the left and right hands leftward or rightward in response to the stimulus color. In this setting, the stimulus and response shared two types of correspondence: spatial and motion. The results demonstrated that two SRC effects occurred and interacted (interaction evident only in reaction times [RTs]). RT distribution analysis and accuracy delta plots for each SRC effect indicated that spatial and motion SRC are distinct phenomena based on different processes.
Directory of Open Access Journals (Sweden)
Lothar Eysn
2015-05-01
Full Text Available In this study, eight airborne laser scanning (ALS-based single tree detection methods are benchmarked and investigated. The methods were applied to a unique dataset originating from different regions of the Alpine Space covering different study areas, forest types, and structures. This is the first benchmark ever performed for different forests within the Alps. The evaluation of the detection results was carried out in a reproducible way by automatically matching them to precise in situ forest inventory data using a restricted nearest neighbor detection approach. Quantitative statistical parameters such as percentages of correctly matched trees and omission and commission errors are presented. The proposed automated matching procedure presented herein shows an overall accuracy of 97%. Method based analysis, investigations per forest type, and an overall benchmark performance are presented. The best matching rate was obtained for single-layered coniferous forests. Dominated trees were challenging for all methods. The overall performance shows a matching rate of 47%, which is comparable to results of other benchmarks performed in the past. The study provides new insight regarding the potential and limits of tree detection with ALS and underlines some key aspects regarding the choice of method when performing single tree detection for the various forest types encountered in alpine regions.
Directory of Open Access Journals (Sweden)
Ryabov Yuri
2012-03-01
Full Text Available The creation of an area of freedom, security and justice is one of the most rapidly developing aspects of European integration. It this paper, we take a look at the foreign policies involved in this process — aside from the internal development of the European Union, they concern a significant number of third countries, including Russia. In our view, the efforts to manage the flow of migrants and asylum seekers constitute a viable part of the external dimension within the AFSJ policies. Much of this article is based on the theoretical postulates introduced by the scholars of the Paris School, a school within the discipline of security studies that conceptualized the connection between migration, terrorism, asylum, crime and ethnic clashes, and its role as a major threat facing the European Union. Externalization of this complex threat (that is, externalization in relation to the European Union is thus seen as one of the key prerequisites to advancement of migration management activities beyond the EU (i. e. externalization of migration management. In this article, we analyze the role the EU plays at the international scene and categorize the actions it took to manage the influx of migrants and asylum seekers from the 1980s until the time when supranational administrative bodies were granted mandates in the spheres of Justice and Home Affairs (JHA of the EU Member States. We conclude that it was as early as the 1990-s that the EU launched the policy which later allowed to transfer part of its security concerns to third countries.
Directory of Open Access Journals (Sweden)
Shih-Sen Chang
1994-01-01
Full Text Available In this paper, we introduce the concept of more general probabilistic contractors in probabilistic normed spaces and show the existence and uniqueness of solutions for set-valued and single-valued nonlinear operator equations in Menger probabilistic normed spaces.
Directory of Open Access Journals (Sweden)
Lisa William-White
2012-06-01
Full Text Available Using the work of Judith Butler on gender regulation, Black Feminist Thought (BFT, and autobiographic storytelling, this piece illustrates how essentialist notions of gender, and discourses related to gender create conflict in shaping identity construction for a Black woman academic and single mother (BWA/SM in the United States. This piece reveals complex gendered and racialized tropes related to notions of motherhood and womanhood, particularly within the author’s own family. Included here is how the author attempts to transcend these complexities in her quest for selfdefinition and selfactualization, unbridled by gender norms. Yet, race, gender and parental status are significant intersecting categories in identity construction, andinherent in the constructions are hegemonic discourses with which the author continues to grapple. Consequently, the struggle to transcend these forces is further complicated by the limited representation of Black women in the US academy, and by the types of academic work where they find themselves typically situated.
International Nuclear Information System (INIS)
Dudas, Emilian; Papineau, Chloe; Rubakov, Valery
2006-01-01
We analyze the properties of a model with four-dimensional brane-localized Higgs type potential of a six dimensional scalar field satisfying the Dirichlet boundary condition on the boundary of a transverse two-dimensional compact space. The regularization of the localized couplings generates classical renormalization group running. A tachyonic mass parameter grows in the infrared, in analogy with the QCD gauge coupling in four dimensions. We find a phase transition at a critical value of the bare mass parameter such that the running mass parameter becomes large in the infrared precisely at the compactification scale. Below the critical coupling, the theory is in symmetric phase, whereas above it spontaneous symmetry breaking occurs. Close to the phase transition point there is a very light mode in the spectrum. The massive Kaluza-Klein spectrum at the critical coupling becomes independent of the UV cutoff
A unified theory in higher dimensions
Energy Technology Data Exchange (ETDEWEB)
Kapetanakis, D. (National Research Centre for the Physical Sciences Democritos, Athens (Greece)); Zoupanos, G. (European Organization for Nuclear Research, Geneva (Switzerland))
1990-10-11
We present a grand unified model defined in ten dimensions and based on the group SO(13). The model is dimensionally reduced over the non-simply-connected space (Su(3)/U(1)xU(1))/Z{sub 2} giving in four dimensions the standard model. (orig.).
A unified theory in higher dimensions
International Nuclear Information System (INIS)
Kapetanakis, D.; Zoupanos, G.
1990-01-01
We present a grand unified model defined in ten dimensions and based on the group SO(13). The model is dimensionally reduced over the non-simply-connected space [Su(3)/U(1)xU(1)]/Z 2 giving in four dimensions the standard model. (orig.)
Gholibeigian, Hassan; Gholibeigian, Ghasem; Amirshahkarami, Azim; Gholibeigian, Kazem
2017-01-01
Four animated sub-particles (sub-strings) as origin of the life and generator of momentum (vibration) of elementary particles (strings) are communicated for transferring information for processing and preparing fundamental particles for the next step. It means that information may be a ``dimension'' of the nature which fundamental particles, dark matter/energy and space-time are floating in it and listening to its whispering and getting quantum information packages about their conditions and laws. So, communication of information which began before the spark to B.B. (Convection Bang), may be a ``Fundamental symmetry'' in the nature because leads other symmetries and supersymmetry as well as other phenomena. The processed information are always carried by fundamental particles as the preserved history and entropy of Universe. So, information wouldn't be destroyed, lost or released by black hole. But the involved fundamental particles of thermal radiation, electromagnetic and gravitational fields carry processed information during emitting from black hole, while they are communicated from fifth dimension for their new movement. AmirKabir University of Technology, Tehran, Iran.
Bellini, A.; Bianchini, P.; Varri, A. L.; Anderson, J.; Piotto, G.; van der Marel, R. P.; Vesperini, E.; Watkins, L. L.
2017-08-01
High-precision proper motions of the globular cluster 47 Tuc have allowed us to measure for the first time the cluster rotation in the plane of the sky and the velocity anisotropy profile from the cluster core out to about 13‧. These profiles are coupled with prior measurements along the line of sight (LOS) and the surface brightness profile and fit all together with self-consistent models specifically constructed to describe quasi-relaxed stellar systems with realistic differential rotation, axisymmetry, and pressure anisotropy. The best-fit model provides an inclination angle i between the rotation axis and the LOS direction of 30° and is able to simultaneously reproduce the full three-dimensional kinematics and structure of the cluster, while preserving a good agreement with the projected morphology. Literature models based solely on LOS measurements imply a significantly different inclination angle (i = 45°), demonstrating that proper motions play a key role in constraining the intrinsic structure of 47 Tuc. Our best-fit global dynamical model implies an internal rotation higher than previous studies have shown and suggests a peak of the intrinsic V/σ ratio of ∼0.9 at around two half-light radii, with a nonmonotonic intrinsic ellipticity profile reaching values up to 0.45. Our study unveils a new degree of dynamical complexity in 47 Tuc, which may be leveraged to provide new insights into the formation and evolution of globular clusters. Based on archival observations with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by AURA, Inc., under NASA contract NAS 5-26555.
Sakhr, Jamal; Nieminen, John M.
2018-03-01
Two decades ago, Wang and Ong, [Phys. Rev. A 55, 1522 (1997)], 10.1103/PhysRevA.55.1522 hypothesized that the local box-counting dimension of a discrete quantum spectrum should depend exclusively on the nearest-neighbor spacing distribution (NNSD) of the spectrum. In this Rapid Communication, we validate their hypothesis by deriving an explicit formula for the local box-counting dimension of a countably-infinite discrete quantum spectrum. This formula expresses the local box-counting dimension of a spectrum in terms of single and double integrals of the NNSD of the spectrum. As applications, we derive an analytical formula for Poisson spectra and closed-form approximations to the local box-counting dimension for spectra having Gaussian orthogonal ensemble (GOE), Gaussian unitary ensemble (GUE), and Gaussian symplectic ensemble (GSE) spacing statistics. In the Poisson and GOE cases, we compare our theoretical formulas with the published numerical data of Wang and Ong and observe excellent agreement between their data and our theory. We also study numerically the local box-counting dimensions of the Riemann zeta function zeros and the alternate levels of GOE spectra, which are often used as numerical models of spectra possessing GUE and GSE spacing statistics, respectively. In each case, the corresponding theoretical formula is found to accurately describe the numerically computed local box-counting dimension.
OPTIMAL PARTITIONS OF DATA IN HIGHER DIMENSIONS
National Aeronautics and Space Administration — OPTIMAL PARTITIONS OF DATA IN HIGHER DIMENSIONS BRADLEY W. JACKSON*, JEFFREY D. SCARGLE, AND CHRIS CUSANZA, DAVID BARNES, DENNIS KANYGIN, RUSSELL SARMIENTO, SOWMYA...
DEFF Research Database (Denmark)
Kwon, Jun Bum; Wang, Xiongfei; Bak, Claus Leth
2015-01-01
The increasing number of renewable energy sources at the distribution grid is becoming a major issue for utility companies, since the grid connected converters are operating at different operating points due to the probabilistic characteristics of renewable energy. Besides, typically, the harmonics...... proposes a new model of a single phase grid connected renewable energy source using the Harmonic State Space modeling approach, which is able to identify such problems and the model can be extended to be applied in the multiple connected converter analysis. The modeling results show the different harmonic...... and impedance from other renewable energy sources are not taken carefully into account in the installation and design. However, this may bring an unknown harmonic instability into the multiple power sourced system and also make the analysis difficult due to the complexity of the grid network. This paper...
Vyhnalek, Brian E.; Tedder, Sarah A.; Nappier, Jennifer M.
2018-01-01
Space-to-ground photon-counting optical communication links supporting high data rates over large distances require enhanced ground receiver sensitivity in order to reduce the mass and power burden on the spacecraft transmitter. Superconducting nanowire single-photon detectors (SNSPDs) have been demonstrated to offer superior performance in detection efficiency, timing resolution, and count rates over semiconductor photodetectors, and are a suitable technology for high photon efficiency links. Recently photon detectors based on superconducting nanowires have become commercially available, and we have assessed the characteristics and performance of one such commercial system as a candidate for potential utilization in ground receiver designs. The SNSPD system features independent channels which can be added modularly, and we analyze the scalability of the system to support different data rates, as well as consider coupling concepts and issues as the number of channels increases.
International Nuclear Information System (INIS)
Lalucaa, Valerian
2013-01-01
This thesis studies the single event effects of space environment in CMOS image sensors (CIS). This work focuses on the effects of heavy ions on 3T standard photodiode pixels, and 4T and 5T pinned photodiode pixels. The first part describes the space radioactive environment and the sensor architecture. The most harmful events (SEL and SETs) are identified thanks to the scientific literature. The experimentally tested sensors agree with the theoretical work. SETs are compared to STARDUST simulations with a good agreement for all ions and sensors. The work explains why the SETs on 3T pixels are insensitive to the various photodiode designs, and they are decreased when an epitaxial substrate is used. A method using anti-blooming was successfully used in 4T and 5T pixels to prevent the spread of the SETs. The mechanism of latch-up in 4T pixel sensors is described. All the identified mechanisms are very useful to provide hardening methods for the CISs. (author) [fr
Zwieniecki, Maciej A; Boyce, C Kevin; Holbrook, N Michele
2004-10-01
Morphological diversity of leaves is usually quantified with geometrical characters, while in many cases a simple set of biophysical parameters are involved in constraining size and shape. One of the main physiological functions of the leaf is transpiration and thus one can expect that leaf hydraulic parameters can be used to predict potential morphologies, although with the caveat that morphology in turn influences physiological parameters including light interception and boundary layer thickness and thereby heat transfer and net photosynthesis. An iterative model was used to determine the relative sizes and shapes that are functionally possible for single-veined leaves as defined by their ability to supply the entire leaf lamina with sufficient water to prevent stomatal closure. The model variables include the hydraulic resistances associated with vein axial and radial transport, as well as with water movement through the mesophyll and the leaf surface. The four parameters included in the model are sufficient to define a hydraulic functional design space that includes all single-veined leaf shapes found in nature, including scale-, awl- and needle-like morphologies. This exercise demonstrates that hydraulic parameters have dissimilar effects: surface resistance primarily affects leaf size, while radial and mesophyll resistances primarily affect leaf shape. These distinctions between hydraulic parameters, as well as the differential accessibility of different morphologies, might relate to the convergent evolutionary patterns seen in a variety of fossil lineages concerning overall morphology and anatomical detail that frequently have evolved in linear and simple multi-veined leaves.
Dacuña, Javier
2012-09-06
We used a mobility edge transport model and solved the drift-diffusion equation to characterize the space-charge-limited current of a rubrene single-crystal hole-only diode. The current-voltage characteristics suggest that current is injection-limited at high voltage when holes are injected from the bottom contact (reverse bias). In contrast, the low-voltage regime shows that the current is higher when holes are injected from the bottom contact as compared to hole injection from the top contact (forward bias), which does not exhibit injection-limited current in the measured voltage range. This behavior is attributed to an asymmetric distribution of trap states in the semiconductor, specifically, a distribution of traps located near the top contact. Accounting for a localized trap distribution near the contact allows us to reproduce the temperature-dependent current-voltage characteristics in forward and reverse bias simultaneously, i.e., with a single set of model parameters. We estimated that the local trap distribution contains 1.19×1011 cm -2 states and decays as exp(-x/32.3nm) away from the semiconductor-contact interface. The local trap distribution near one contact mainly affects injection from the same contact, hence breaking the symmetry in the charge transport. The model also provides information of the band mobility, energy barrier at the contacts, and bulk trap distribution with their corresponding confidence intervals. © 2012 American Physical Society.
Goldie dimension of rings of fractions of C ( X ) | Afrooz ...
African Journals Online (AJOL)
Finally, for each cardinal a, we show that there exists a space X and a multiplicatively closed set S in C(X) such that the Goldie dimension of S-1C(X) is α. Keywords: Goldie dimension, F-spaces, P-spaces, locally domains, reduced rings, Bezout rings, rank of a point, local cellularity, local Souslin property, at module, ...
New black holes in five dimensions
International Nuclear Information System (INIS)
Lue, H.; Mei Jianwei; Pope, C.N.
2009-01-01
We construct new stationary Ricci-flat metrics of cohomogeneity 2 in five dimensions, which generalise the Myers-Perry rotating black hole metrics by adding a further non-trivial parameter. We obtain them via a construction that is analogous to the construction by Plebanski and Demianski in four dimensions of the most general type D metrics. Limiting cases of the new metrics contain not only the general Myers-Perry black hole with independent angular momenta, but also the single rotation black ring of Emparan and Reall. In another limit, we obtain new static metrics that describe black holes whose horizons are distorted lens spaces L(n;m)=S 3 /Γ(n;m), where m≥n+2≥3. They are asymptotic to Minkowski spacetime factored by Γ(m;n). In the general stationary case, by contrast, the new metrics describe spacetimes with a horizon and with a periodicity condition on the time coordinate; these examples can be thought of as five-dimensional analogues of the four-dimensional Taub-NUT metrics
Quantum matrices in two dimensions
International Nuclear Information System (INIS)
Ewen, H.; Ogievetsky, O.; Wess, J.
1991-01-01
Quantum matrices in two-dimensions, admitting left and right quantum spaces, are classified: they fall into two families, the 2-parametric family GL p,q (2) and a 1-parametric family GL α J (2). Phenomena previously found for GL p,q (2) hold in this general situation: (a) powers of quantum matrices are again quantum and (b) entries of the logarithm of a two-dimensional quantum matrix form a Lie algebra. (orig.)
Berg, Melanie; LaBel, Kenneth; Campola, Michael; Xapsos, Michael
2017-01-01
We are investigating the application of classical reliability performance metrics combined with standard single event upset (SEU) analysis data. We expect to relate SEU behavior to system performance requirements. Our proposed methodology will provide better prediction of SEU responses in harsh radiation environments with confidence metrics. single event upset (SEU), single event effect (SEE), field programmable gate array devises (FPGAs)
Goparaju Purna SUDHAKAR
2013-01-01
Popularity of teams is growing in 21st Century. Organizations are getting their work done through different types of teams. Teams have proved that the collective performance is more than the sum of the individual performances. Thus, the teams have got different dimensions such as quantitative dimensions and qualitative dimensions. The Quantitative dimensions of teams such as team performance, team productivity, team innovation, team effectiveness, team efficiency, team decision making and tea...
Seljak, A.; Cumming, H. S.; Varner, G.; Vallerga, J.; Raffanti, R.; Virta, V.
2018-02-01
Our collaboration works on the development of a large aperture, high resolution, UV single-photon imaging detector, funded through NASA's Strategic Astrophysics Technology (SAT) program. The detector uses a microchannel plate for charge multiplication, and orthogonal cross strip (XS) anodes for charge readout. Our target is to make an advancement in the technology readiness level (TRL), which enables real scale prototypes to be tested for future NASA missions. The baseline detector has an aperture of 50×50 mm and requires 160 low-noise charge-sensitive channels, in order to extrapolate the incoming photon position with a spatial resolution of about 20 μm FWHM. Technologies involving space flight require highly integrated electronic systems operating at very low power. We have designed two ASICs which enable the construction of such readout system. First, a charge sensitive amplifier (CSAv3) ASIC provides an equivalent noise charge (ENC) of around 600 e-, and a baseline gain of 10 mV/fC. The second, a Giga Sample per Second (GSPS) ASIC, called HalfGRAPH, is a 12-bit analog to digital converter. Its architecture is based on waveform sampling capacitor arrays and has about 8 μs of analog storage memory per channel. Both chips encapsulate 16 measurement channels. Using these chips, a small scale prototype readout system has been constructed on a FPGA Mezzanine Board (FMC), equipped with 32 measurement channels for system evaluation. We describe the construction of HalfGRAPH ASIC, detector's readout system concept and obtained results from the prototype system. As part of the space flight qualification, these chips were irradiated with a Cobalt gamma-ray source, to verify functional operation under ionizing radiation exposure.
Dimensions of Creative Evaluation
DEFF Research Database (Denmark)
Christensen, Bo; Ball, Linden J.
2016-01-01
We examined evaluative reasoning taking place during expert ‘design critiques’. We focused on key dimensions of creative evaluation (originality, functionality and aesthetics) and ways in which these dimensions impact reasoning strategies and suggestions offered by experts for how the student could...... continue. Each dimension was associated with a specific underpinning ‘logic’ determining how these dimensions were evaluated in practice. Our analysis clarified how these dimensions triggered reasoning strategies such as running mental simulations or making design suggestions, ranging from ‘go...
International Nuclear Information System (INIS)
Koomey, J.G.; McMahon, J.E.; Wodley, C.
1991-07-01
This report summarizes the costs and space-conditioning load savings from improving new single-family building shells. It relies on survey data from the National Association of Home-builders (NAHB) to assess current insulation practices for these new buildings, and NAHB cost data (aggregated to the Federal region level) to estimate the costs of improving new single-family buildings beyond current practice. Space-conditioning load savings are estimated using a database of loads for prototype buildings developed at Lawrence Berkeley Laboratory, adjusted to reflect population-weighted average weather in each of the ten federal regions and for the nation as a whole
2013-01-01
The book aims at nurturing theoretic reflection on the city and the territory and working out and applying methods and techniques for improving our physical and social landscapes. The main issue is developed around the projectual dimension, with the objective of visualising both the city and the territory from a particular viewpoint, which singles out the territorial dimension as the city’s space of communication and negotiation. Issues that characterise the dynamics of city development will be faced, such as the new, fresh relations between urban societies and physical space, the right to the city, urban equity, the project for the physical city as a means to reveal civitas, signs of new social cohesiveness, the sense of contemporary public space and the sustainability of urban development. Authors have been invited to explore topics that feature a pluralism of disciplinary contributions studying formal and informal practices on the project for the city and seeking conceptual and operative categories capab...
Kim, Jaewook; Hong, Kwangwoo; Choi, Sunghwan; Hwang, Sang-Yeon; Youn Kim, Woo
2015-12-21
We developed a program code of configuration interaction singles (CIS) based on a numerical grid method. We used Kohn-Sham (KS) as well as Hartree-Fock (HF) orbitals as a reference configuration and Lagrange-sinc functions as a basis set. Our calculations show that KS-CIS is more cost-effective and more accurate than HF-CIS. The former is due to the fact that the non-local HF exchange potential greatly reduces the sparsity of the Hamiltonian matrix in grid-based methods. The latter is because the energy gaps between KS occupied and virtual orbitals are already closer to vertical excitation energies and thus KS-CIS needs small corrections, whereas HF results in much larger energy gaps and more diffuse virtual orbitals. KS-CIS using the Lagrange-sinc basis set also shows a better or a similar accuracy to smaller orbital space compared to the standard HF-CIS using Gaussian basis sets. In particular, KS orbitals from an exact exchange potential by the Krieger-Li-Iafrate approximation lead to more accurate excitation energies than those from conventional (semi-) local exchange-correlation potentials.
Natural generalization of Slater determinants to more than one dimension
Sunko, Denis
The calculation of realistic N-body wave functions for identical fermions is still an open problem in physics, chemistry, and materials science, even for N as small as two. Here a fundamental algebraic structure of many-body Hilbert space is described, enabling theoretically well-founded systematic investigation of wave-function space. The structure allows an arbitrary many-fermion wave function to be written in terms of a finite number of antisymmetric functions called shapes, which cannot be constructed by combining one-dimensional wave functions. Shapes naturally generalize the single-Slater-determinant form for the ground state to more than one dimension. Their number is exactly N! d - 1 in d dimensions. A general algorithm is given to list them all in terms of standard Slater determinants. Conversely, excitations which can be induced from the one-dimensional case are bosonised into a system of distinguishable bosons, called Euler bosons, much like the electromagnetic field is quantized in terms of photons distinguishable by their wave numbers. Their wave functions are given explicitly in terms of elementary symmetric functions, reflecting the fact that the fermion sign problem is trivial in one dimension. The shapes are all possible vacua for the Euler bosons.
DEFF Research Database (Denmark)
Boby, Mathews; Rahul, Arun; Gopakumar, K.
2018-01-01
Conventional voltage-source inverters used for induction motor drives generate a hexagonal space vector structure. In the overmodulation range, the hexagonal space vector structure generates low-order harmonics in the phase voltage resulting in low-order torque ripple in the motor. Inverter...... topologies with an octadecagonal (18 sided) space vector structure eliminate fifth-, seventh-, eleventh-, and thirteenth-order harmonics from the phase voltage, and hence, the dominant sixth- and twelfth-order torque ripple generation is eliminated. Octadecagonal space vector structures proposed in the past...... require multiple dc sources, which makes four-quadrant operation of the drive system difficult and costly. In this paper, the formation of a multilevel nine-concentric octadecagonal space vector structure using a single dc source is proposed. Detailed experimental results, using open-loop V/f control...
Space - the essential dimension of sustainable development
DEFF Research Database (Denmark)
Buch-Hansen, Mogens
be accumulated as waste being an obstacle for new development. If this circular process can be repeated indefinitely, the development is truly sustainable. However, sustainability involves many aspects, and most importantly the aims of development. That includes the meaning of value and hereby the moral....../ethical framework for development. Development studies show us how differently the circular process has been evolving through history around the globe. Development is by definition building on anthropocentric values, i.e. the society is manipulating ‘nature' for maximum utility. Natural resources - or natural...
search of extra space dimensions with ATLAs
Indian Academy of Sciences (India)
of intense phenomenological study. 2. ATLAS studies. The sensitivity of the ATLAs detector to a number of phenomenological models have been studied. The results of some of these studies are reported in the following sections. Most of these studies have used a parameter-based fast Monte Carlo,. ATLFAsT, to simulate ...
Piecewise flat gravity in 3+1 dimensions
van de Meent, M.
2011-01-01
We study a model for gravity in 3+1 dimensions, inspired in general relativity in 2+1 dimensions. In contrast regular general relativity in 3+1 dimensions, the model postulates that space in absence of matter is flat. The requirement that the Einstein equation still holds for the complete spacetime,
Superconformal Theories in Six Dimensions
Arvidsson, Par
2006-08-01
This thesis consists of an introductory text, which is divided into two parts, and six appended research papers. The first part contains a general discussion on conformal and superconformal symmetry in six dimensions, and treats how the corresponding transformations act on space-time and superspace fields. We specialize to the case with chiral (2,0) supersymmetry. A formalism is presented for incorporating these symmetries in a manifest way. The second part of the thesis concerns the so called (2,0) theory in six dimensions. The different origins of this theory in terms of higher-dimensional theories (Type IIB string theory and M-theory) are treated, as well as compactifications of the six-dimensional theory to supersymmetric Yang-Mills theories in five and four space-time dimensions. The free (2,0) tensor multiplet field theory is introduced and discussed, and we present a formalism in which its superconformal covariance is made manifest. We also introduce a tensile self-dual string and discuss how to couple this string to the tensor multiplet fields in a way that respects superconformal invariance.
International Nuclear Information System (INIS)
Grinberg, H.
1983-11-01
The projection operator method of Zwanzig and Feshbach is used to construct the time-dependent field operators in the interaction picture. The formula developed to describe the time dependence involves time-ordered cosine and sine projected evolution (memory) superoperators, from which a master equation for the interaction-picture single-particle Green's function in a Liouville space is derived. (author)
DEFF Research Database (Denmark)
Lykke, Marianne; Jantzen, Christian
2016-01-01
The present study develops a set of 10 dimensions based on a systematic understanding of the concept of experience as a holistic psychological. Seven of these are derived from a psychological conception of what experiencing and experiences are. Three supplementary dimensions spring from...... the observation that experiences apparently have become especially valuable phenomena in Western societies. The 10 dimensions are tried out in a field study at the Center for Art and Media (ZKM) in Germany with the purpose to study their applicability in the evaluation of interactive sound archives. 29 walk......-alongs were carried out with 58 museums visitors. Our analysis showed that it was possible to identify the 10 experience dimensions in the study material. Some dimensions were expressed more frequently than others. The distribution of expressed dimensions and the content of the user comments provided a clear...
Rosiyadi, Didi; Suryana, Nana; Cahyana, Ade; Nuryani, Nuryani
2007-01-01
Makalah ini mengemukakan E-Government Dimension yang merupakan salah satu hasil TahapanPengumpulan Data, dimana tahapan ini adalah bagian dari penelitian kompetitif di Lembaga Ilmu PengetahuanIndonesia 2007 yang sekarang sedang dilakukan. Data E-Government Dimension ini didapatkan dari berbagaisumber yang meliputi E-Government beberapa Negara di dunia, E-Government yang dibangun oleh beberapapenyedia aplikasi E-Government. E-Government Dimension terdiri dari tiga dimensi yaitu DemocraticDimen...
Multiple dimensions of performance
Torenvlied, René
2013-01-01
This presentation considers the multiple dimensions of performance in performance studies, and potentially contradicting effects of different management strategies on separate indicators of performance
Gorenstein homological dimensions
DEFF Research Database (Denmark)
Holm, Henrik Granau
2004-01-01
In basic homological algebra, the projective, injective and 2at dimensions of modules play an important and fundamental role. In this paper, the closely related Gorenstein projective, Gorenstein injective and Gorenstein 2at dimensions are studied. There is a variety of nice results about Gorenstein...... dimensions over special commutative noetherian rings; very often local Cohen–Macaulay rings with a dualizing module. These results are done by Avramov, Christensen, Enochs, Foxby, Jenda, Martsinkovsky and Xu among others. The aim of this paper is to generalize these results, and to give homological...... descriptions of the Gorenstein dimensions over arbitrary associative rings....
Fractal dimension for fractal structures: A Hausdorff approach
Fernández-Martínez, M.; Sánchez-Granero, M.A.
2012-01-01
This paper provides a new model to compute the fractal dimension of a subset on a generalized-fractal space. Recall that fractal structures are a perfect place where a new definition of fractal dimension can be given, so we perform a suitable discretization of the Hausdorff theory of fractal dimension. We also find some connections between our definition and the classical ones and also with fractal dimensions I & II (see http://arxiv.org/submit/0080421/pdf). Therefore, we generalize them and ...
Navigating between the Dimensions
Fleron, Julian F.; Ecke, Volker
2011-01-01
Generations have been inspired by Edwin A. Abbott's profound tour of the dimensions in his novella "Flatland: A Romance of Many Dimensions" (1884). This well-known satire is the story of a flat land inhabited by geometric shapes trying to navigate the subtleties of their geometric, social, and political positions. In this article, the authors…
Dimensions of Occupational Prestige
Haug, Marie R.; Widdison, Harold A.
1975-01-01
Eight dimensions of occupational prestige are examined for their effect on the general prestige ratings accorded various occupations within the medical profession. Stepwise multiple regression analyzes the relative weight of these dimension among 410 persons. The findings suggested that public stereotypes exert a normative pressure on individual…
Geometric Dimensioning Sentence Structure.
McCuistion, Patrick J.
1991-01-01
Explanations of geometric dimensioning symbols are provided to assist in the comprehension of the implied basic sentence structure of modern geometric dimensioning and tolerance. The proper identification and interpretation of the substantive language within several exemplary engineering drawings, otherwise called feature control frames, is…
Dimensions of Adolescent Employment.
Mael, Fred A.; Morath, Ray A.; McLellan, Jeffrey A.
1997-01-01
Examines positive and negative correlates of adolescent work as a function of work dimensions. Results indicate that concurrent costs and benefits of adolescent employment may depend on dimensions of work as well as adolescent characteristics. Adolescent employment was generally related to subsequent work motivation and nonacademic performance.…
Baumstark-Khan, C.; Hellweg, C.; Arenz, A.
2005-08-01
The German experiment "Cellular Responses to Radiation in Space (CERASP)", to be performed on the International Space Station (ISS) will supply basic information on the cellular response to radiation applied in microgravity. One of the biological endpoints under investigation will be gene activation by space flight conditions in mammalian cells, based on fluorescent promoter reporter systems using green fluorescent protein. The promoter element to be investigated reflects the activity of the nuclear factor kappa B (NF-κB) pathway. Results obtained with X-rays and accelerated argon ions (95 MeV/u, LET 230 keV/μm) produced at the French heavy ion accelerator GANIL imply that densely ionizing radiation has a stronger potential to activate NF-κB dependent gene expression than sparsely ionizing radiation.
DEFF Research Database (Denmark)
Høskuldsson, Agnar
1996-01-01
Determination of the proper dimension of a given linear model is one of the most important tasks in the applied modeling work. We consider here eight criteria that can be used to determine the dimension of the model, or equivalently, the number of components to use in the model. Four of these cri......Determination of the proper dimension of a given linear model is one of the most important tasks in the applied modeling work. We consider here eight criteria that can be used to determine the dimension of the model, or equivalently, the number of components to use in the model. Four...... the basic problems in determining the dimension of linear models. Then each of the eight measures are treated. The results are illustrated by examples....
The fourth dimension simply explained
Manning, Henry P
2005-01-01
To remove the contents of an egg without puncturing its shell or to drink the liquor in a bottle without removing the cork is clearly unthinkable - or is it? Understanding the world of Einstein and curved space requires a logical conception of the fourth dimension.This readable, informative volume provides an excellent introduction to that world, with 22 essays that employ a minimum of mathematics. Originally written for a contest sponsored by Scientific American, these essays are so well reasoned and lucidly written that they were judged to merit publication in book form. Their easily unders
Hellweg, C. E.; Thelen, M.; Arenz, A.; Baumstark-Khan, C.
The combined action of ionizing radiation and microgravity will continue to influence future manned space missions, with special risks for astronauts on the Moon surface or for long duration missions to Mars. There is increasing evidence that basic cellular functions are sensitive not only to radiation but also to microgravity. Previous space flight experiments gave contradictory results: from inhibition of DNA repair by microgravity to enhancement, whereas others did not detect any influence of microgravity on repair. At the Radiation Biology Department of the German Aerospace Center (DLR), recombinant bacterial and mammalian cell systems were developed as reporters for cellular signal transduction modulation by genotoxic environmental conditions. The space experiment “Cellular Responses to Radiation in Space” (CERASP) to be performed at the International Space Station (ISS) will make use of such reporter cell lines thereby supplying basic information on the cellular response to radiation applied in microgravity. One of the biological endpoints will be survival reflected by radiation-dependent reduction of constitutive expression of the enhanced variant of green fluorescent protein (EGFP). A second end-point will be gene activation by space flight conditions in mammalian cells, based on fluorescent promoter reporter systems using the destabilized d2EGFP variant. The promoter element to be investigated reflects the activity of the nuclear factor kappa B (NF-κB) pathway. The NF-κB family of proteins plays a major role in the inflammatory and immune response, cell proliferation and differentiation, apoptosis and tumor genesis. Results obtained with X-rays and accelerated heavy ions produced at the French heavy ion accelerator GANIL imply that densely ionizing radiation has a stronger potential to activate NF-κB dependent gene expression than sparsely ionizing radiation. The correlation of NF-κB activation to negative regulation of apoptosis could favor
Rau, Markus; Heindel, Tobias; Unsleber, Sebastian; Braun, Tristan; Fischer, Julian; Frick, Stefan; Nauerth, Sebastian; Schneider, Christian; Vest, Gwenaelle; Reitzenstein, Stephan; Kamp, Martin; Forchel, Alfred; Höfling, Sven; Weinfurter, Harald
2014-04-01
Highly efficient single-photon sources (SPS) can increase the secure key rate of quantum key distribution (QKD) systems compared to conventional attenuated laser systems. Here we report on a free space QKD test using an electrically driven quantum dot single-photon source (QD SPS) that does not require a separate laser setup for optical pumping and thus allows for a simple and compact SPS QKD system. We describe its implementation in our 500 m free space QKD system in downtown Munich. Emulating a BB84 protocol operating at a repetition rate of 125 MHz, we could achieve sifted key rates of 5-17 kHz with error ratios of 6-9% and {{\\text{g}}^{(2)}}(0)-values of 0.39-0.76.
Kondaveeti, Sanath; Moon, Jung Mi; Min, Booki
2017-12-01
The performance of a single chamber microbial fuel cell (MFC) with a low-cost polypropylene separator was investigated at various electrode interspaces in a separator electrode assembly (SEA). The lag period was shortened (3.74-0.17 days) and voltage generation was enhanced (0.2-0.5 V) as electrode spacing was increased from 0 to 9 mm. Power density was increased from 220 to 370 mW/m 2 with increased spacing. The highest power density of 488 mW/m 2 was obtained in polarization analysis with 6 mm. The oxygen mass transfer coefficients with 0 mm (K o = 3.69 × 10 -5 cm/s) electrode spacing were 3.8 times higher than with 9 mm (K o = 0.96 × 10 -5 cm/s) spacing. Columbic efficiency (CE) was increased from 5 to 32% due to less oxygen diffusion with increase in electrode spacing, but on contrary the ohmic resistance (R oh ) was increased from 2 to 4 Ω. In a long-term operation (200 days), a gradual decrease in cathode potentials was observed in all electrode spacing as the main limiting factor of stable MFC performance.
CERN. Geneva. Audiovisual Unit
2002-01-01
Recent progress in the formulation of fundamental theories for a Universe with more than 4 dimensions will be reviewed. Particular emphasis will be given to theories predicting the existence of extra dimensions at distance scales within the reach of current or forthcoming experiments. The phenomenological implications of these theories, ranging from detectable deviations from Newton's law at sub-millimeter scales, to phenomena of cosmological and astrophysical interest, as well as to high-energy laboratory experiments, will be discussed.
Directory of Open Access Journals (Sweden)
Rafa Espínola
2010-01-01
Full Text Available We study the existence of fixed points and convergence of iterates for asymptotic pointwise contractions in uniformly convex metric spaces. We also study the existence of fixed points for set-valued nonexpansive mappings in the same class of spaces. Our results do not assume convexity of the metric which makes a big difference when studying the existence of fixed points for set-valued mappings.
Alternating dimension plasma transport in three dimensions
Energy Technology Data Exchange (ETDEWEB)
Grad, H.
1979-12-01
The alternating dimension (1 1/2 D) method of solving macroscopic adiabatic and transport problems is here generalized to arbitrary 3-D toroidal plasma confinement systems. The principal new result is the derivation of an evolution equation for the poloidal and toroidal fluxes in which second derivatives can be explicitly exhibited to show that the system is diffusive. This extends previous results in 2-D, axial symmetry and helical symmetry, where the flux functions for the magnetic field are explicit consequences of an ignorable coordinate, and the EBT closed magnetic line configuration. The eigenvalues (diffusion coefficients) are evaluated and are shown to represent one-dimensional relative diffusion among the adiabatic variables, independent of the representation (e.g. whether diffusion is measured relative to mass, or toroidal flux, or poloidal flux). The skin effect diffusion coefficient decouples from the other coefficients and represents diffusion of one magnetic field component relative to the other. Other transport coefficients such as those for mass and energy flow are intrinsically coupled. As in previously implemented alternating dimension codes, a 3-D code built to these specifications should be expected to be extremely accurate and efficient.
Time-space noncommutative Abelian solitons
International Nuclear Information System (INIS)
Chu, C.-S.; Lechtenfeld, Olaf
2005-01-01
We demonstrate the construction of solitons for a time-space Moyal-deformed integrable U(n) sigma model (the Ward model) in 2+1 dimensions. These solitons cannot travel parallel to the noncommutative spatial direction. For the U(1) case, the rank-one single-soliton configuration is constructed explicitly and is singular in the commutative limit. The projection to 1+1 dimensions transforms it to a noncommutative instanton-like configuration. The latter is governed by a new integrable equation, which describes a Moyal-deformed sigma model with a particular Euclidean metric and a magnetic field
Intersection democracy for winding branes and stabilization of extra dimensions
Energy Technology Data Exchange (ETDEWEB)
Rador, Tonguc [Bogazici University Department of Physics, 34342 Bebek, istanbul (Turkey)]. E-mail: tonguc.rador@boun.edu.tr
2005-08-11
We show that, in the context of pure Einstein gravity, a democratic principle for intersection possibilities of branes winding around extra dimensions in a given partitioning yield stabilization, while what the observed space follows is matter-like dust evolution. Here democracy is used in the sense that, in a given decimation of extra dimensions, all possible wrappings and hence all possible intersections are allowed. Generally, the necessary and sufficient condition for this is that the dimensionality m of the observed space dimensions obey 3=
A variational principle for the Hausdorff dimension of fractal sets
DEFF Research Database (Denmark)
Olsen, Lars; Cutler, Colleen D.
1994-01-01
Matematik, fraktal (fractal), Hausdorff dimension, Renyi dimension, pakke dimension (packing dimension)......Matematik, fraktal (fractal), Hausdorff dimension, Renyi dimension, pakke dimension (packing dimension)...
Thermodynamic stability of asymptotically anti-de Sitter rotating black holes in higher dimensions
International Nuclear Information System (INIS)
Dolan, Brian P
2014-01-01
Conditions for thermodynamic stability of asymptotically anti-de Sitter (AdS) rotating black holes in D-dimensions are determined. Local thermodynamic stability requires not only positivity conditions on the specific heat and the moment of inertia tensor but it is also necessary that the adiabatic compressibility be positive. It is shown that, in the absence of a cosmological constant, neither rotation nor charge is sufficient to ensure full local thermodynamic stability of a black hole. Thermodynamic stability properties of AdS Myers–Perry black holes are investigated for both singly spinning and multi-spinning black holes. Simple expressions are obtained for the specific heat and moment of inertia tensor in any dimension. An analytic expression is obtained for the boundary of the region of parameter space in which such space-times are thermodynamically stable. (paper)
Scaling and universality in two dimensions
DEFF Research Database (Denmark)
Bellotti, Filipe Furlan; Frederico, T.; Yamashita, M. T.
2011-01-01
The momentum space zero-range model is used to investigate universal properties of three interacting particles confined to two dimensions. The pertinent equations are first formulated for a system of two identical and one distinct particle and the two different two-body subsystems are characterized...
Laplacian eigenmodes for spherical spaces
International Nuclear Information System (INIS)
Lachieze-Rey, M; Caillerie, S
2005-01-01
The possibility that our space is multi-rather than singly-connected has gained renewed interest after the discovery of the low power for the first multipoles of the CMB by WMAP. To test the possibility that our space is a multi-connected spherical space, it is necessary to know the eigenmodes of such spaces. Except for lens and prism space, and to some extent for dodecahedral space, this remains an open problem. Here we derive the eigenmodes of all spherical spaces. For dodecahedral space, the demonstration is much shorter, and the calculation method much simpler than before. We also apply our method to tetrahedric, octahedric and icosahedric spaces. This completes the knowledge of eigenmodes for spherical spaces, and opens the door to new observational tests of the cosmic topology. The vector space V k of the eigenfunctions of the Laplacian on the 3-sphere S 3 , corresponding to the same eigenvalue λ k = -k(k + 2), has dimension (k + 1) 2 . We show that the Wigner functions provide a basis for such a space. Using the properties of the latter, we express the behaviour of a general function of V k under an arbitrary rotation G of SO(4). This offers the possibility of selecting those functions of V k which remain invariant under G. Specifying G to be a generator of the holonomy group of a spherical space X, we give the expression of the vector space V x k of the eigenfunctions of X. We provide a method to calculate the eigenmodes up to an arbitrary order. As an illustration, we give the first modes for the spherical spaces mentioned
DEFF Research Database (Denmark)
Dalsgaard, Christian; Thestrup, Klaus
2015-01-01
The objective of the paper is to present a pedagogical approach to openness. The paper develops a framework for understanding the pedagogical opportunities of openness in education. Based on the pragmatism of John Dewey and sociocultural learning theory, the paper defines openness in education as...... for openness. With examples from a university case, the paper discusses how alternative pedagogical formats and educational technologies can support the three dimensions of openness....... as a matter of engaging educational activities in sociocultural practices of a surrounding society. Openness is not only a matter of opening up the existing, but of developing new educational practices that interact with society. The paper outlines three pedagogical dimensions of openness: transparency...... practices. Openness as joint engagement in the world aims at establishing interdependent collaborative relationships between educational institutions and external practices. To achieve these dimensions of openness, educational activities need to change and move beyond the course as the main format...
On universal quantum dimensions
Directory of Open Access Journals (Sweden)
R.L. Mkrtchyan
2017-08-01
Full Text Available We represent in the universal form restricted one-instanton partition function of supersymmetric Yang–Mills theory. It is based on the derivation of universal expressions for quantum dimensions (universal characters of Cartan powers of adjoint and some other series of irreps of simple Lie algebras. These formulae also provide a proof of formulae for universal quantum dimensions for low-dimensional representations, needed in derivation of universal knot polynomials (i.e. colored Wilson averages of Chern–Simons theory on 3d sphere. As a check of the (complicated formulae for universal quantum dimensions we prove numerically Deligne's hypothesis on universal characters for symmetric cube of adjoint representation.
International Nuclear Information System (INIS)
Antoniadis, I
2006-01-01
Lowering the string scale in the TeV region provides a theoretical framework for solving the mass hierarchy problem and unifying all interactions. The apparent weakness of gravity can then be accounted by the existence of large internal dimensions, in the submillimeter region, and transverse to a braneworld where our universe must be confined. I review the main properties of this scenario and its implications for observations at both particle colliders, and in non-accelerator gravity experiments. Such effects are for instance the production of Kaluza-Klein resonances, graviton emission in the bulk of extra dimensions, and a radical change of gravitational forces in the submillimeter range
Trembach, Vera
2014-01-01
Space is an introduction to the mysteries of the Universe. Included are Task Cards for independent learning, Journal Word Cards for creative writing, and Hands-On Activities for reinforcing skills in Math and Language Arts. Space is a perfect introduction to further research of the Solar System.
Dang, Haizheng; Tan, Jun; Zha, Rui; Li, Jiaqi; Zhang, Lei; Zhao, Yibo; Gao, Zhiqian; Bao, Dingli; Li, Ning; Zhang, Tao; Zhao, Yongjiang; Zhao, Bangjian
2017-12-01
This paper presents a review of recent advances in single- and multi-stage Stirling-type pulse tube cryocoolers (SPTCs) for space applications developed at the National Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences (NLIP/SITP/CAS). A variety of single-stage SPTCs operating at 25-150 K have been developed, including several mid-sized ones operating at 80-110 K. Significant progress has been achieved in coolers operating at 30-40 K which use common stainless steel meshes as regenerator matrices. Another important advance is the micro SPTCs with an overall mass of 300-800 g operating at high frequencies varying from 100 Hz to 400 Hz. The main purpose of developing two-stage SPTCs is to simultaneously acquire cooling capacities at both stages, obviating the need for auxiliary precooling in various applications. The three-stage SPTCs are developed mainly for applications at around 10 K, which are also used for precooling the J-T coolers to achieve further lower temperatures. The four-stage SPTCs are developed to directly achieve the liquid helium temperature for cooling space low-Tc superconducting devices and for the deep space exploration as well. Several typical development programs are described and an overview of the cooler performances is presented.
Selective Attention to Perceptual Dimensions and Switching between Dimensions
Meiran, Nachshon; Dimov, Eduard; Ganel, Tzvi
2013-01-01
In the present experiments, the question being addressed was whether switching attention between perceptual dimensions and selective attention to dimensions are processes that compete over a common resource? Attention to perceptual dimensions is usually studied by requiring participants to ignore a never-relevant dimension. Selection failure…
William-White, Lisa
2012-01-01
Using the work of Judith Butler on gender regulation, Black Feminist Thought (BFT), and autobiographic storytelling, this piece illustrates how essentialist notions of gender, and discourses related to gender create conflict in shaping identity construction for a Black woman academic and single mother (BWA/SM) in the United States. This piece…
Unified Theories from Fuzzy Extra Dimensions
Aschieri, P.; Manousselis, P.; Zoupanos, G.
2004-01-01
We combine and exploit ideas from Coset Space Dimensional Reduction (CSDR) methods and Non-commutative Geometry. We consider the dimensional reduction of gauge theories defined in high dimensions where the compact directions are a fuzzy space (matrix manifold). In the CSDR one assumes that the form of space-time is M^D=M^4 x S/R with S/R a homogeneous space. Then a gauge theory with gauge group G defined on M^D can be dimensionally reduced to M^4 in an elegant way using the symmetries of S/R, in particular the resulting four dimensional gauge is a subgroup of G. In the present work we show that one can apply the CSDR ideas in the case where the compact part of the space-time is a finite approximation of the homogeneous space S/R, i.e. a fuzzy coset. In particular we study the fuzzy sphere case.
BOOK REVIEW: Black Holes, Cosmology and Extra Dimensions Black Holes, Cosmology and Extra Dimensions
Frolov, Valeri P.
2013-10-01
flatness of the Universe, the horizon problem and isotropy of cosmological microwave background. All this material is covered in chapter seven. Chapter eight contains brief discussion of several popular inflation models. Chapter nine is devoted to the problem of the large-scale structure formation from initial quantum vacuum fluctuation during the inflation and the spectrum of the density fluctuations. It also contains remarks on the baryonic asymmetry of the Universe, baryogenesis and primordial black holes. Part III covers the material on extra dimensions. It describes how Einstein gravity is modified in the presence of one or more additional spatial dimensions and how these extra dimensions are compactified in the Kaluza-Klein scheme. The authors also discuss how extra dimensions may affect low energy physics. They present examples of higher-dimensional generalizations of the gravity with higher-in-curvature corrections and discuss a possible mechanism of self-stabilization of an extra space. A considerable part of the chapter 10 is devoted to cosmological models with extra dimensions. In particular, the authors discuss how extra dimensions can modify 'standard' inflation models. At the end of this chapter they make several remarks on a possible relation of the value of fundamental constants in our universe with the existence of extra dimensions. Finally, in chapter 11 they demonstrate that several observable properties of the Universe are closely related with the special value of the fundamental physical constants and their fine tuning. They give interesting examples of such fine tuning and summarize many other cases. The book ends with discussion of a so-called 'cascade birth of universes in multidimensional spaces' model, proposed by one of the authors. As is evident from this brief summary of topics presented in the book, many interesting areas of modern gravity and cosmology are covered. However, since the subject is so wide, this inevitably implies that the
Scalar field cosmology in three-dimensions
International Nuclear Information System (INIS)
Oliveira Neto, G.
2001-01-01
We study an analytical solution to the Einstein's equations in 2 + 1-dimensions. The space-time is dynamical and has a line symmetry. The matter content is a minimally coupled, massless, scalar field. Depending on the value of certain parameters, this solution represents three distinct space-times. The first one is at space-time. Then, we have a big bang model with a negative curvature scalar and a real scalar field. The last case is a big bang model with event horizons where the curvature scalar vanishes and the scalar field changes from real to purely imaginary. (author)
Czech Academy of Sciences Publication Activity Database
Zapletal, Jindřich
2014-01-01
Roč. 167, April 15 (2014), s. 31-35 ISSN 0166-8641 R&D Projects: GA AV ČR IAA100190902 Institutional support: RVO:67985840 Keywords : Cohen real * infinite dimension * calibrated ideal Subject RIV: BA - General Mathematics Impact factor: 0.551, year: 2014 http://www.sciencedirect.com/science/article/pii/S0166864114001151
Michels-Clark, Tara M; Savici, Andrei T; Lynch, Vickie E; Wang, Xiaoping; Hoffmann, Christina M
2016-04-01
Evidence is mounting that potentially exploitable properties of technologically and chemically interesting crystalline materials are often attributable to local structure effects, which can be observed as modulated diffuse scattering (mDS) next to Bragg diffraction (BD). BD forms a regular sparse grid of intense discrete points in reciprocal space. Traditionally, the intensity of each Bragg peak is extracted by integration of each individual reflection first, followed by application of the required corrections. In contrast, mDS is weak and covers expansive volumes of reciprocal space close to, or between, Bragg reflections. For a representative measurement of the diffuse scattering, multiple sample orientations are generally required, where many points in reciprocal space are measured multiple times and the resulting data are combined. The common post-integration data reduction method is not optimal with regard to counting statistics. A general and inclusive data processing method is needed. In this contribution, a comprehensive data analysis approach is introduced to correct and merge the full volume of scattering data in a single step, while correctly accounting for the statistical weight of the individual measurements. Development of this new approach required the exploration of a data treatment and correction protocol that includes the entire collected reciprocal space volume, using neutron time-of-flight or wavelength-resolved data collected at TOPAZ at the Spallation Neutron Source at Oak Ridge National Laboratory.
DEFF Research Database (Denmark)
Deng, Jie; Tian, Zhiyong; Fan, Jianhua
2016-01-01
A pilot project of the solar water heating system combined with a low temperature air source heat pump (ASHP) unit was established in 2014 in a detached residential house in the rural region of Beijing, in order to investigate the system application prospect for single family houses via system op...... the integrated solar space heating for reducing carbon emission, it is suggested that the Beijing municipal government should offer some financial subsidy to compensate the equivalent solar heat price per kWh....... pilot household on the current electricity price level of 0.5 RMB/kWh, comparing with the reference condition of the fully ASHP space heating. It is further found that the equivalent solar heat price per kWh is too high under the current solar market cost price and collector technology. To put forward...
A four-dimensional virtual hand brain-machine interface using active dimension selection
Rouse, Adam G.
2016-06-01
Objective. Brain-machine interfaces (BMI) traditionally rely on a fixed, linear transformation from neural signals to an output state-space. In this study, the assumption that a BMI must control a fixed, orthogonal basis set was challenged and a novel active dimension selection (ADS) decoder was explored. Approach. ADS utilizes a two stage decoder by using neural signals to both (i) select an active dimension being controlled and (ii) control the velocity along the selected dimension. ADS decoding was tested in a monkey using 16 single units from premotor and primary motor cortex to successfully control a virtual hand avatar to move to eight different postures. Main results. Following training with the ADS decoder to control 2, 3, and then 4 dimensions, each emulating a grasp shape of the hand, performance reached 93% correct with a bit rate of 2.4 bits s-1 for eight targets. Selection of eight targets using ADS control was more efficient, as measured by bit rate, than either full four-dimensional control or computer assisted one-dimensional control. Significance. ADS decoding allows a user to quickly and efficiently select different hand postures. This novel decoding scheme represents a potential method to reduce the complexity of high-dimension BMI control of the hand.
A four-dimensional virtual hand brain-machine interface using active dimension selection.
Rouse, Adam G
2016-06-01
Brain-machine interfaces (BMI) traditionally rely on a fixed, linear transformation from neural signals to an output state-space. In this study, the assumption that a BMI must control a fixed, orthogonal basis set was challenged and a novel active dimension selection (ADS) decoder was explored. ADS utilizes a two stage decoder by using neural signals to both (i) select an active dimension being controlled and (ii) control the velocity along the selected dimension. ADS decoding was tested in a monkey using 16 single units from premotor and primary motor cortex to successfully control a virtual hand avatar to move to eight different postures. Following training with the ADS decoder to control 2, 3, and then 4 dimensions, each emulating a grasp shape of the hand, performance reached 93% correct with a bit rate of 2.4 bits s(-1) for eight targets. Selection of eight targets using ADS control was more efficient, as measured by bit rate, than either full four-dimensional control or computer assisted one-dimensional control. ADS decoding allows a user to quickly and efficiently select different hand postures. This novel decoding scheme represents a potential method to reduce the complexity of high-dimension BMI control of the hand.
Directory of Open Access Journals (Sweden)
Oskar SKOMSKI
2017-11-01
Full Text Available The main assumption of this paper is to analyse the Sejm elections of 2015 results. The authors conducted a simulation study regarding the single-member constituencies in the election to the Polish Parliament, basing the research on the election results facilitated by National Electoral Commission as well as the specific data provided by Central Statistical Office. The division of Poland into 460 single-member constituencies was mapped by the authors (those maps do not include the district divisions in the cities, as the agglomerations’ division is problematic. Obtained results indicate to the marginalization of the Polish political scene – plural voting would preclude the election victories of the secondary political parties and civil rights movements.
DEFF Research Database (Denmark)
Börner, Richard; Ehrlich, Nicky; Hohlbein, Johannes
2016-01-01
. As the method is based on the detection of single photons, it additionally allows for performing fluorescence correlation spectroscopy (FCS) as well as dynamical anisotropy measurements thereby providing access to fast orientational dynamics down to the nanosecond time scale. The 3D orientation is particularly...... interesting in non-isotropic environments such as lipid membranes, which are of great importance in biology. We used giant unilamellar vesicles (GUVs) labeled with fluorescent dyes down to a single molecule concentration as a model system for both, assessing the robustness of the orientation determination...... simulations of the rotational dynamics of dipoles incorporated into lipid membranes. Our study offers a comprehensive view on the dye orientation behavior in a lipid membrane with high spatiotemporal resolution representing a six-dimensional fluorescence detection approach....
Interactive Dimensioning of Parametric Models
Kelly, T.
2015-06-22
We propose a solution for the dimensioning of parametric and procedural models. Dimensioning has long been a staple of technical drawings, and we present the first solution for interactive dimensioning: A dimension line positioning system that adapts to the view direction, given behavioral properties. After proposing a set of design principles for interactive dimensioning, we describe our solution consisting of the following major components. First, we describe how an author can specify the desired interactive behavior of a dimension line. Second, we propose a novel algorithm to place dimension lines at interactive speeds. Third, we introduce multiple extensions, including chained dimension lines, controls for different parameter types (e.g. discrete choices, angles), and the use of dimension lines for interactive editing. Our results show the use of dimension lines in an interactive parametric modeling environment for architectural, botanical, and mechanical models.
A simpler and elegant algorithm for computing fractal dimension in ...
Indian Academy of Sciences (India)
Conventional algorithms for computing dimension of such systems in higher dimen- sional state space face an unavoidable problem of enormous storage requirement. Here we present an algorithm, which uses a simple but very powerful technique and faces no problem in computing dimension in higher dimensional state ...
A simpler and elegant algorithm for computing fractal dimension in ...
Indian Academy of Sciences (India)
Chaotic systems are now frequently encountered in almost all branches of sciences. Dimension of such systems provides an important measure for easy characterization of dynamics of the systems. Conventional algorithms for computing dimension of such systems in higher dimensional state space face an unavoidable ...
Localization transition in one dimension using Wegner flow equations
Quito, Victor L.; Titum, Paraj; Pekker, David; Refael, Gil
2016-09-01
The flow-equation method was proposed by Wegner as a technique for studying interacting systems in one dimension. Here, we apply this method to a disordered one-dimensional model with power-law decaying hoppings. This model presents a transition as function of the decaying exponent α . We derive the flow equations and the evolution of single-particle operators. The flow equation reveals the delocalized nature of the states for α 1/2 , we present a strong-bond renormalization group structure based on iterating the three-site clusters, where we solve the flow equations perturbatively. This renormalization group approach allows us to probe the critical point (α =1 ). This method correctly reproduces the critical level-spacing statistics and the fractal dimensionality of the eigenfunctions.
Ren, Yongxiong; Liu, Cong; Pang, Kai; Zhao, Jiapeng; Cao, Yinwen; Xie, Guodong; Li, Long; Liao, Peicheng; Zhao, Zhe; Tur, Moshe; Boyd, Robert W; Willner, Alan E
2017-12-01
We experimentally demonstrate spatial multiplexing of an orbital angular momentum (OAM)-encoded quantum channel and a classical Gaussian beam with a different wavelength and orthogonal polarization. Data rates as large as 100 MHz are achieved by encoding on two different OAM states by employing a combination of independently modulated laser diodes and helical phase holograms. The influence of OAM mode spacing, encoding bandwidth, and interference from the co-propagating Gaussian beam on registered photon count rates and quantum bit error rates is investigated. Our results show that the deleterious effects of intermodal crosstalk effects on system performance become less important for OAM mode spacing Δ≥2 (corresponding to a crosstalk value of less than -18.5 dB). The use of OAM domain can additionally offer at least 10.4 dB isolation besides that provided by wavelength and polarization, leading to a further suppression of interference from the classical channel.
2014-06-30
set of methods, many of which have their origin in probability in Banach spaces , that arise across a broad range of contemporary problems in di↵erent...salesman problem, . . . • Probability in Banach spaces : probabilistic limit theorems for Banach - valued random variables, empirical processes, local...theory of Banach spaces , geometric functional analysis, convex geometry. • Mixing times and other phenomena in high-dimensional Markov chains. At
Random holographic "large worlds" with emergent dimensions
Trugenberger, Carlo A.
2016-11-01
I propose a random network model governed by a Gaussian weight corresponding to Ising link antiferromagnetism as a model for emergent quantum space-time. In this model, discrete space is fundamental, not a regularization; its spectral dimension ds is not a model input but is, rather, completely determined by the antiferromagnetic coupling constant. Perturbative terms suppressing triangles and favoring squares lead to locally Euclidean ground states that are Ricci flat "large worlds" with power-law extension. I then consider the quenched graphs of lowest energy for ds=2 and ds=3 , and I show how quenching leads to the spontaneous emergence of embedding spaces of Hausdorff dimension dH=4 and dH=5 , respectively. One of the additional, spontaneous dimensions can be interpreted as time, causality being an emergent property that arises in the large N limit (with N the number of vertices). For ds=2 , the quenched graphs constitute a discrete version of a 5D-space-filling surface with a number of fundamental degrees of freedom scaling like N2 /5, a graph version of the holographic principle. These holographic degrees of freedom can be identified with the squares of the quenched graphs, which, being triangle-free, are the fundamental area (or loop) quanta.
Random holographic "large worlds" with emergent dimensions.
Trugenberger, Carlo A
2016-11-01
I propose a random network model governed by a Gaussian weight corresponding to Ising link antiferromagnetism as a model for emergent quantum space-time. In this model, discrete space is fundamental, not a regularization; its spectral dimension d_{s} is not a model input but is, rather, completely determined by the antiferromagnetic coupling constant. Perturbative terms suppressing triangles and favoring squares lead to locally Euclidean ground states that are Ricci flat "large worlds" with power-law extension. I then consider the quenched graphs of lowest energy for d_{s}=2 and d_{s}=3, and I show how quenching leads to the spontaneous emergence of embedding spaces of Hausdorff dimension d_{H}=4 and d_{H}=5, respectively. One of the additional, spontaneous dimensions can be interpreted as time, causality being an emergent property that arises in the large N limit (with N the number of vertices). For d_{s}=2, the quenched graphs constitute a discrete version of a 5D-space-filling surface with a number of fundamental degrees of freedom scaling like N^{2/5}, a graph version of the holographic principle. These holographic degrees of freedom can be identified with the squares of the quenched graphs, which, being triangle-free, are the fundamental area (or loop) quanta.
Introduction to Extra Dimensions
Energy Technology Data Exchange (ETDEWEB)
Rizzo, Thomas G.; /SLAC
2010-04-29
Extra dimensions provide a very useful tool in addressing a number of the fundamental problems faced by the Standard Model. The following provides a very basic introduction to this very broad subject area as given at the VIII School of the Gravitational and Mathematical Physics Division of the Mexican Physical Society in December 2009. Some prospects for extra dimensional searches at the 7 TeV LHC with {approx}1 fb{sup -1} of integrated luminosity are provided.
Energy Technology Data Exchange (ETDEWEB)
Emery, V.J.
1981-03-01
This article is a qualitative account of some aspects of physics in few dimensions, and its relationship to nonlinear field theories. After a survey of materials and some of the models that have been used to describe them, the various methods of solution are compared and contrasted. The roles of exact results, operator representations and the renormalization group transformation are described, and a uniform picture of the behavior of low-dimensional systems is presented.
International Nuclear Information System (INIS)
Emery, V.J.
1981-03-01
This article is a qualitative account of some aspects of physics in few dimensions, and its relationship to nonlinear field theories. After a survey of materials and some of the models that have been used to describe them, the various methods of solution are compared and contrasted. The roles of exact results, operator representations and the renormalization group transformation are described, and a uniform picture of the behavior of low-dimensional systems is presented
Kou, Zhuangfei; Shen, Jun; Xu, Enhua; Li, Shuhua
2012-05-21
Based on the coupled-cluster singles, doubles, and a hybrid treatment of triples (CCSD(T)-h) method developed by us [J. Shen, E. Xu, Z. Kou, and S. Li, J. Chem. Phys. 132, 114115 (2010); and ibid. 133, 234106 (2010); and ibid. 134, 044134 (2011)], we developed and implemented a new hybrid coupled cluster (CC) method, named CCSD(T)q-h, by combining CC singles and doubles, and active triples and quadruples (CCSDtq) with CCSD(T) to deal with the electronic structures of molecules with significant multireference character. These two hybrid CC methods can be solved with non-canonical and canonical MOs. With canonical MOs, the CCSD(T)-like equations in these two methods can be solved directly without iteration so that the storage of all triple excitation amplitudes can be avoided. A practical procedure to divide canonical MOs into active and inactive subsets is proposed. Numerical calculations demonstrated that CCSD(T)-h with canonical MOs can well reproduce the corresponding results obtained with non-canonical MOs. For three atom exchange reactions, we found that CCSD(T)-h can offer a significant improvement over the popular CCSD(T) method in describing the reaction barriers. For the bond-breaking processes in F(2) and H(2)O, our calculations demonstrated that CCSD(T)q-h is a good approximation to CCSDTQ over the entire bond dissociation processes.
Pham, Hung Q; Bernales, Varinia; Gagliardi, Laura
2018-03-13
Density matrix embedding theory (DMET) [ Phys. Rev. Lett. 2012, 109, 186404] has been demonstrated as an efficient wave-function-based embedding method to treat extended systems. Despite its success in many quantum lattice models, the extension of DMET to real chemical systems has been tested only on selected cases. Herein, we introduce the use of the complete active space self-consistent field (CASSCF) method as a correlated impurity solver for DMET, leading to a method called CAS-DMET. We test its performance in describing the dissociation of H-H single bonds in a H 10 ring model system and an N═N double bond in azomethane (CH 3 -N═N-CH 3 ) and pentyldiazene (CH 3 (CH 2 ) 4 -N═NH). We find that the performance of CAS-DMET is comparable to CASSCF with different active space choices when single-embedding DMET corresponding to only one embedding problem for the system is used. When multiple embedding problems are used for the system, the CAS-DMET is in good agreement with CASSCF for the geometries around the equilibrium, but not in equal agreement at bond dissociation.
Roy, Robert J.; Wilson, Mark E.; Diderich, Greg S.; Steele, John W.
2011-01-01
The International Space Station (ISS) Oxygen Generator Assembly (OGA) operational performance may be adversely impacted by microbiological growth and biofilm formation over the electrolysis cell membranes. Biofilms could hinder the transport of water from the bulk fluid stream to the membranes and increase the cell concentration overpotential resulting in higher cell voltages and a shorter cell life. A microbial challenge test was performed on duplicate single liquid-cathode feed water electrolysis cells to evaluate operational performance with increasing levels of a mixture of five bacteria isolated from ISS and Space Shuttle potable water systems. Baseline performance of the single water electrolysis cells was determined for approximately one month with deionized water. Monthly performance was also determined following each inoculation of the feed tank with 100, 1000, 10,000 and 100,000 cells/ml of the mixed suspension of test bacteria. Water samples from the feed tank and recirculating water loops for each cell were periodically analyzed for enumeration and speciation of bacteria and total organic carbon. While initially a concern, this test program has demonstrated that the performance of the electrolysis cell is not adversely impacted by feed water containing the five species of bacteria tested at a concentration measured as high as 1,000,000 colony forming units (CFU)/ml. This paper presents the methodologies used in the conduct of this test program along with the performance test results at each level of bacteria concentration.
Sato, Yoichiro; Imanishi, Yorihisa; Tomita, Toshiki; Ozawa, Hiroyuki; Sakamoto, Koji; Fujii, Ryoichi; Shigetomi, Seiji; Habu, Noboru; Otsuka, Kuninori; Watanabe, Yoshihiro; Sekimizu, Mariko; Ogawa, Kaoru
2018-03-01
Because the incidence of schwannoma arising from the parapharyngeal space (PPS) is very low, no studies have analyzed extirpation methods and postoperative neurological complications exclusively in PPS schwannomas. The preoperative diagnosis and clinical outcomes of surgical treatment in 21 patients with PPS schwannoma who underwent surgery were investigated. Neurological deficit of the involved nerve developed in all patients regardless of the extirpation method used. However, the incidence of first bite syndrome in sympathetic chain schwannoma was significantly lower after intracapsular enucleation (40%) than after total resection (100%; P = .045). Furthermore, the incidence of postoperative complications unrelated to the involved nerve was lower after intracapsular enucleation (0%) than after total resection (42.9%; P = .055). Although postoperative neurological deficit of the involved nerve was unavoidable in PPS schwannoma, intracapsular enucleation could be beneficial by reducing its severity and the incidence of complications unrelated to the involved nerve. © 2017 Wiley Periodicals, Inc.
Realistic Field Theories on Submanifolds of Compact Extra Dimensions
Energy Technology Data Exchange (ETDEWEB)
Mirabelli, E.
2005-04-05
In this thesis, they study various physical models which assume the existence of spatial dimensions beyond the familiar three. While everyday observation suggests only three dimensions, there is no shortage of potential explanations for how extra dimensions could have escaped detection for so long. For instance, the extra dimensions could be compact, curled into a microscopic volume so that you can never move far in the extra dimensions without ending up back where you started. Or, the elements of everyday experience could be trapped on a three-dimensional membrane floating in a higher dimensions space. The models studied in this thesis each use both of these mechanisms in tandem, with electrons, photons, quarks, and the like being confined to a three-dimensional membrane that sits in a space with compact extra dimensions. Gravitons (and perhaps other new types of particles) could travel beyond the three-dimensional membrane, so they can feel the effects of the higher-dimensional space, but because the extra dimensions are compactified on a small scale, the effects are subtle.
Accelerated Dimension-Independent Adaptive Metropolis
Chen, Yuxin
2016-10-27
This work describes improvements by algorithmic and architectural means to black-box Bayesian inference over high-dimensional parameter spaces. The well-known adaptive Metropolis (AM) algorithm [H. Haario, E. Saksman, and J. Tamminen, Bernoulli, (2001), pp. 223--242] is extended herein to scale asymptotically uniformly with respect to the underlying parameter dimension for Gaussian targets, by respecting the variance of the target. The resulting algorithm, referred to as the dimension-independent adaptive Metropolis (DIAM) algorithm, also shows improved performance with respect to adaptive Metropolis on non-Gaussian targets. This algorithm is further improved, and the possibility of probing high-dimensional (with dimension $d \\\\geq 1000$) targets is enabled, via GPU-accelerated numerical libraries and periodically synchronized concurrent chains (justified a posteriori). Asymptotically in dimension, this GPU implementation exhibits a factor of four improvement versus a competitive CPU-based Intel MKL (math kernel library) parallel version alone. Strong scaling to concurrent chains is exhibited, through a combination of longer time per sample batch (weak scaling) with fewer necessary samples to convergence. The algorithm performance is illustrated on several Gaussian and non-Gaussian target examples, in which the dimension may be in excess of one thousand.
Massively Parallel Dimension Independent Adaptive Metropolis
Chen, Yuxin
2015-05-14
This work considers black-box Bayesian inference over high-dimensional parameter spaces. The well-known and widely respected adaptive Metropolis (AM) algorithm is extended herein to asymptotically scale uniformly with respect to the underlying parameter dimension, by respecting the variance, for Gaussian targets. The result- ing algorithm, referred to as the dimension-independent adaptive Metropolis (DIAM) algorithm, also shows improved performance with respect to adaptive Metropolis on non-Gaussian targets. This algorithm is further improved, and the possibility of probing high-dimensional targets is enabled, via GPU-accelerated numerical libraries and periodically synchronized concurrent chains (justified a posteriori). Asymptoti- cally in dimension, this massively parallel dimension-independent adaptive Metropolis (MPDIAM) GPU implementation exhibits a factor of four improvement versus the CPU-based Intel MKL version alone, which is itself already a factor of three improve- ment versus the serial version. The scaling to multiple CPUs and GPUs exhibits a form of strong scaling in terms of the time necessary to reach a certain convergence criterion, through a combination of longer time per sample batch (weak scaling) and yet fewer necessary samples to convergence. This is illustrated by e ciently sampling from several Gaussian and non-Gaussian targets for dimension d 1000.
Mapping soil fractal dimension in agricultural fields with GPR
Oleschko, K.; Korvin, G.; Muñoz, A.; Velazquez, J.; Miranda, M. E.; Carreon, D.; Flores, L.; Martínez, M.; Velásquez-Valle, M.; Brambila, F.; Parrot, J.-F.; Ronquillo, G.
2008-09-01
We documented that the mapping of the fractal dimension of the backscattered Ground Penetrating Radar traces (Fractal Dimension Mapping, FDM) accomplished over heterogeneous agricultural fields gives statistically sound combined information about the spatial distribution of Andosol' dielectric permittivity, volumetric and gravimetric water content, bulk density, and mechanical resistance under seven different management systems. The roughness of the recorded traces was measured in terms of a single number H, the Hurst exponent, which integrates the competitive effects of volumetric water content, pore topology and mechanical resistance in space and time. We showed the suitability to combine the GPR traces fractal analysis with routine geostatistics (kriging) in order to map the spatial variation of soil properties by nondestructive techniques and to quantify precisely the differences under contrasting tillage systems. Three experimental plots with zero tillage and 33, 66 and 100% of crop residues imprinted the highest roughness to GPR wiggle traces (mean HR/S=0.15), significantly different to Andosol under conventional tillage (HR/S=0.47).
Mapping soil fractal dimension in agricultural fields with GPR
Directory of Open Access Journals (Sweden)
K. Oleschko
2008-09-01
Full Text Available We documented that the mapping of the fractal dimension of the backscattered Ground Penetrating Radar traces (Fractal Dimension Mapping, FDM accomplished over heterogeneous agricultural fields gives statistically sound combined information about the spatial distribution of Andosol' dielectric permittivity, volumetric and gravimetric water content, bulk density, and mechanical resistance under seven different management systems. The roughness of the recorded traces was measured in terms of a single number H, the Hurst exponent, which integrates the competitive effects of volumetric water content, pore topology and mechanical resistance in space and time. We showed the suitability to combine the GPR traces fractal analysis with routine geostatistics (kriging in order to map the spatial variation of soil properties by nondestructive techniques and to quantify precisely the differences under contrasting tillage systems. Three experimental plots with zero tillage and 33, 66 and 100% of crop residues imprinted the highest roughness to GPR wiggle traces (mean H_{R/S}=0.15, significantly different to Andosol under conventional tillage (H_{R/S}=0.47.
Dimensions of energy efficiency
International Nuclear Information System (INIS)
Ramani, K.V.
1992-01-01
In this address the author describes three dimensions of energy efficiency in order of increasing costs: conservation, resource and technology substitution, and changes in economic structure. He emphasizes the importance of economic rather than environmental rationales for energy efficiency improvements in developing countries. These countries do not place high priority on the problems of global climate change. Opportunities for new technologies may exist in resource transfer, new fuels and, possibly, small reactors. More research on economic and social impacts of technologies with greater sensitivity to user preferences is needed
DEFF Research Database (Denmark)
Andersen, lotte bøgh; Beck Jørgensen, Torben; Kjeldsen, Anne-Mette
2012-01-01
Further integration of the public value literature with other strands of literature within Public Administration necessitates a more specific classification of public values. This paper applies a typology linked to organizational design principles, because this is useful for empirical public...... administration studies. Based on an existing typology of modes of governance, we develop a classification and test it empirically, using survey data from a study of the values of 501 public managers. We distinguish between seven value dimensions (the public at large, rule abidance, societal interests, budget...... the integration between the public value literature and other parts of the Public Administration discipline....
Dimension and deriving manner for derived quantities
International Nuclear Information System (INIS)
Zhao Zhixiang
1993-01-01
Most physical quantities we are interested in are derived from some directly measured physical quantities. To obtain correct least-square result in derived quantity space, one must pay attention to inconsistencies problem to avoid ppp phenomenon in generating derived quantities and their covariance matrix. The situation is complicated by the problems of dimension and deriving manner for derived quantities. Some more general problems, which are independent of ppp, are discussed
Quantum vortex fluid in two dimensions
International Nuclear Information System (INIS)
Chudnovsky, E.M.
1995-01-01
It is argued that in two dimensions the high-field zero-temperature phase of a type-II superconductor can be quantum vortex fluid. The average intervortex spacing in this phase takes discrete values, leading to macroscopic steps in the total flux through the superconductor on the applied magnetic field. In the absence of dissipation, the Hall conductivity is quantized in units of 4e 2 /πℎ
Romeo, G.; Barnes, R. J.; Ukhorskiy, A. Y.; Sotirelis, T.; Stephens, G.
2017-12-01
The Science Gateway gives single-point access to over 4.5 years of comprehensive wave and particle measurements from the Van Allen Probes NASA twin-spacecraft mission. The Gateway provides a set of visualization and data analysis tools including: HTML5-based interactive visualization of high-level data products from all instrument teams in the form of: line plots, orbital content plots, dynamical energy spectra, L-shell context plots (including two-spacecraft plotting), FFT spectra of wave data, solar wind and geomagnetic indices data, etc.; download custom multi-instrument CDF data files of selected data products; publication quality plots of digital data; combined orbit predicts for mission planning and coordination including: Van Allen Probes, MMS, THEMIS, Arase (ERG), Cluster, GOES, Geotail, FIREBIRD; magnetic footpoint calculator for coordination with LEO and ground-based assets; real-time computation and processing of empirical magnetic field models - computation of magnetic ephemeris, computation of adiabatic invariants. Van Allen Probes is the first spacecraft mission to provide a nowcast of the radiation environment in the heart of the radiation belts, where the radiation levels are the highest and most dangerous for spacecraft operations. For this purpose, all instruments continuously broadcast a subset of their science data in real time. Van Allen Probes partners with four foreign institutions who operate ground stations that receive the broadcast: Korea (KASI), the Czech republic (CAS), Argentina (CONAE), and Brazil (INPE). The SpWx broadcast is then collected at APL and delivered to the community via the Science Gateway.
1. Dimensions of sustainable development
International Nuclear Information System (INIS)
Repetto, R.
1992-01-01
This chapter discusses the following topics: the concept of sustainable development; envisioning sustainable development (economic dimensions, human dimensions, environmental dimensions, technological dimensions); policy implications (economic policies, people-oriented policies, environmental policies, creating sustainable systems); and global issues (effect of war on development and the environment and the debt burden). This chapter also introduces the case studies by discussing the levels of economic development and comparing key trends (economic growth, human development, population growth, and energy use)
Biomedical engineering - A means to add new dimension to medicine and research
Doerr, D. F.
1992-01-01
Biomedical engineering is an evolving science that seeks to insert technically oriented and trained personnel to assist medical professionals in solving technological problems in the pursuit of innovations in the delivery of health care. Consequently, engineering solutions are brought to bear on problems that previously were outside the training of physicians and beyond the understanding or appreciation of the conventionally educated electrical or mechanical engineers. This physician/scientist/engineer team has a capability to extend medicine and research far beyond the capability of a single entity operating alone. How biomedical engineering has added a new dimension to medical science at the Kennedy Space Center is described.
No Hawking-Page phase transition in three dimensions
International Nuclear Information System (INIS)
Myung, Y.S.
2005-01-01
We investigate whether or not the Hawking-Page phase transition is possible to occur in three dimensions. Starting with the simplest class of Lanczos-Lovelock action, thermodynamic behavior of all AdS-type black holes without charge falls into two classes: Schwarzschild-AdS black holes in even dimensions and Chern-Simons black holes in odd dimensions. The former class can provide the Hawking-Page transition between Schwarzschild-AdS black holes and thermal AdS space. On the other hand, the latter class is exceptional and thus the Hawking-Page transition is hard to occur. In three dimensions, a second-order phase transition might occur between the non-rotating BTZ black hole and the massless BTZ black hole (thermal AdS space), instead of the first-order Hawking-Page transition between the non-rotating BTZ black hole and thermal AdS space
Chern-Simons gravity in four dimensions
Energy Technology Data Exchange (ETDEWEB)
Morales, Ivan; Neves, Bruno; Piguet, Olivier [Universidade Federal de Vicosa (UFV), Departamento de Fisica, Vicosa, MG (Brazil); Oporto, Zui [Universidade Federal de Vicosa (UFV), Departamento de Fisica, Vicosa, MG (Brazil); Universidad Mayor de San Andres, Carrera de Fisica, La Paz (Bolivia, Plurinational State of)
2017-02-15
Five-dimensional Chern-Simons theory with (anti-)de Sitter SO(1,5) or SO(2,4) gauge invariance presents an alternative to general relativity with cosmological constant. We consider the zero modes of its Kaluza-Klein compactification to four dimensions. Solutions with vanishing torsion are obtained in the cases of a spherically symmetric 3-space and of a homogeneous and isotropic 3-space, which reproduce the Schwarzshild-de Sitter and ΛCDM cosmological solutions of general relativity. We also check that vanishing torsion is a stable feature of the solutions. (orig.)
Instantons in six dimensions and twistors
Energy Technology Data Exchange (ETDEWEB)
Ivanova, Tatiana A., E-mail: ita@theor.jinr.ru [Bogoliubov Laboratory of Theoretical Physics, JINR, 141980 Dubna, Moscow Region (Russian Federation); Lechtenfeld, Olaf, E-mail: Olaf.Lechtenfeld@itp.uni-hannover.de [Institut für Theoretische Physik, Leibniz Universität Hannover, Appelstraße 2, 30167 Hannover (Germany); Riemann Center for Geometry and Physics, Leibniz Universität Hannover, Appelstraße 2, 30167 Hannover (Germany); Centre for Quantum Engineering and Space–Time Research, Leibniz Universität Hannover, Welfengarten 1, 30167 Hannover (Germany); Popov, Alexander D., E-mail: Alexander.Popov@itp.uni-hannover.de [Institut für Theoretische Physik, Leibniz Universität Hannover, Appelstraße 2, 30167 Hannover (Germany); Tormählen, Maike, E-mail: Maike.Tormaehlen@itp.uni-hannover.de [Institut für Theoretische Physik, Leibniz Universität Hannover, Appelstraße 2, 30167 Hannover (Germany)
2014-05-15
Recently, conformal field theories in six dimensions were discussed from the twistorial point of view. In particular, it was demonstrated that the twistor transform between chiral zero-rest-mass fields and cohomology classes on twistor space can be generalized from four to six dimensions. On the other hand, the possibility of generalizing the correspondence between instanton gauge fields and holomorphic bundles over twistor space is questionable. It was shown by Sämann and Wolf that holomorphic line bundles over the canonical twistor space Tw(X) (defined as a bundle of almost complex structures over the six-dimensional manifold X) correspond to pure-gauge Maxwell potentials, i.e. the twistor transform fails. On the example of X=CP{sup 3} we show that there exists a twistor correspondence between Abelian or non-Abelian Yang–Mills instantons on CP{sup 3} and holomorphic bundles over complex submanifolds of Tw(CP{sup 3}), but it is not so efficient as in the four-dimensional case because the twistor transform does not parametrize instantons by unconstrained holomorphic data as it does in four dimensions.
Wang, C; Habier, D; Peiris, B L; Wolc, A; Kranis, A; Watson, K A; Avendano, S; Garrick, D J; Fernando, R L; Lamont, S J; Dekkers, J C M
2013-07-01
One approach for cost-effective implementation of genomic selection is to genotype training individuals with a high-density (HD) panel and selection candidates with an evenly spaced, low-density (ELD) panel. The purpose of this study was to evaluate the extent to which the ELD approach reduces the accuracy of genomic estimated breeding values (GEBV) in a broiler line, in which 1,091 breeders from 3 generations were used for training and 160 progeny of the third generation for validation. All birds were genotyped with an Illumina Infinium platform HD panel that included 20,541 segregating markers. Two subsets of HD markers, with 377 (ELD-1) or 766 (ELD-2) markers, were selected as ELD panels. The ELD-1 panel was genotyped using KBiosciences KASPar SNP genotyping chemistry, whereas the ELD-2 panel was simulated by adding markers from the HD panel to the ELD-1 panel. The training data set was used for 2 traits: BW at 35 d on both sexes and hen house production (HHP) between wk 28 and 54. Methods Bayes-A, -B, -C and genomic best linear unbiased prediction were used to estimate HD-marker effects. Two scenarios were used: (1) the 160 progeny were ELD-genotyped, and (2) the 160 progeny and their dams (117 birds) were ELD-genotyped. The missing HD genotypes in ELD-genotyped birds were imputed by a Gibbs sampler, capitalizing on linkage within families. In scenario (1), the correlation of GEBV for BW (HHP) of the 160 progeny based on observed HD versus imputed genotypes was greater than 0.94 (0.98) with the ELD-1 panel and greater than 0.97 (0.99) with the ELD-2 panel. In scenario (2), the correlation of GEBV for BW (HHP) was greater than 0.92 (0.96) with the ELD-1 panel and greater than 0.95 (0.98) with the ELD-2 panel. Hence, in a pedigreed population, genomic selection can be implemented by genotyping selection candidates with about 400 ELD markers with less than 6% loss in accuracy. This leads to substantial savings in genotyping costs, with little sacrifice in accuracy.
Relativistic phase space: dimensional recurrences
International Nuclear Information System (INIS)
Delbourgo, R; Roberts, M L
2003-01-01
We derive recurrence relations between phase space expressions in different dimensions by confining some of the coordinates to tori or spheres of radius R and taking the limit as R→∞. These relations take the form of mass integrals, associated with extraneous momenta (relative to the lower dimension), and produce the result in the higher dimension
COMPARATIVE ANALYSIS OF ANTHROPOMETRIC DIMENSIONS ...
African Journals Online (AJOL)
A comparative analysis of the anthropometric body dimensions of the male and female agricultural workers was conducted in South-Eastern Nigeria to ascertain the variations that exist among the body characteristics/dimensions of the male and female agricultural workers in the area. Thirty (30) anthropometric dimensions ...
Kumagai, Takashi; Ladenthin, Janina N.; Litman, Yair; Rossi, Mariana; Grill, Leonhard; Gawinkowski, Sylwester; Waluk, Jacek; Persson, Mats
2018-03-01
Tautomerization in single porphycene molecules is investigated on Cu(111), Ag(111), and Au(111) surfaces by a combination of low-temperature scanning tunneling microscopy (STM) experiments and density functional theory (DFT) calculations. It is revealed that the trans configuration is the thermodynamically stable form of porphycene on Cu(111) and Ag(111), whereas the cis configuration occurs as a meta-stable form. The trans → cis or cis → trans conversion on Cu(111) can be induced in an unidirectional fashion by injecting tunneling electrons from the STM tip or heating the surface, respectively. We find that the cis ↔ cis tautomerization on Cu(111) occurs spontaneously via tunneling, verified by the negligible temperature dependence of the tautomerization rate below ˜23 K. Van der Waals corrected DFT calculations are used to characterize the adsorption structures of porphycene and to map the potential energy surface of the tautomerization on Cu(111). The calculated barriers are too high to be thermally overcome at cryogenic temperatures used in the experiment and zero-point energy corrections do not change this picture, leaving tunneling as the most likely mechanism. On Ag(111), the reversible trans ↔ cis conversion occurs spontaneously at 5 K and the cis ↔ cis tautomerization rate is much higher than on Cu(111), indicating a significantly smaller tautomerization barrier on Ag(111) due to the weaker interaction between porphycene and the surface compared to Cu(111). Additionally, the STM experiments and DFT calculations reveal that tautomerization on Cu(111) and Ag(111) occurs with migration of porphycene along the surface; thus, the translational motion couples with the tautomerization coordinate. On the other hand, the trans and cis configurations are not discernible in the STM image and no tautomerization is observed for porphycene on Au(111). The weak interaction of porphycene with Au(111) is closest to the gas-phase limit and therefore the absence
Schneider, P.; van der A, R. J.
2012-08-01
A global nine-year archive of monthly tropospheric NO2 data acquired by the SCanning Imaging Absorption spectroMeter for Atmospheric CartograpHY (SCIAMACHY) instrument was analyzed with respect to trends between August 2002 and August 2011. In the past, similar studies relied on combining data from multiple sensors; however, the length of the SCIAMACHY data set now for the first time allows utilization of a consistent time series from just a single sensor for mapping NO2 trends at comparatively high horizontal resolution (0.25°). This study provides an updated analysis of global patterns in NO2 trends and finds that previously reported decreases in tropospheric NO2 over Europe and the United States as well as strong increases over China and several megacities in Asia have continued in recent years. Positive trends of up to 4.05 (±0.41) × 1015 molecules cm-2 yr-1 and up to 19.7 (±1.9) % yr-1 were found over China, with the regional mean trend being 7.3 (±3.1) % yr-1. The megacity with the most rapid relative increase was found to be Dhaka in Bangladesh. Subsequently focusing on Europe, the study further analyzes trends by country and finds significantly decreasing trends for seven countries ranging from -3.0 (±1.6) % yr-1 to -4.5 (±2.3) % yr-1. A comparison of the satellite data with station data indicates that the trends derived from both sources show substantial differences on the station scale, i.e., when comparing a station trend directly with the equivalent satellite-derived trend at the same location, but provide quite similar large-scale spatial patterns. Finally, the SCIAMACHY-derived NO2 trends are compared with equivalent trends in NO2concentration computed using the Co-operative Programme for Monitoring and Evaluation of the Long-range Transmission of Air Pollutants in Europe (EMEP) model. The results show that the spatial patterns in trends computed from both data sources mostly agree in Central and Western Europe, whereas substantial differences
Directory of Open Access Journals (Sweden)
Manikandan Ramasamy
2017-07-01
Full Text Available Automation has been growing in recent years for the manufacturing industries to increase productivity. Multiple robotic arms are used to handle materials for lifting in flexible directions. The vertical rotation of a 360 degree single arm is considered in this research on a position servo drive with brushless DC motor. The load torque of an arm varies depending upon the angular displacement due to gravity, so it requires four-quadrant operation of the drive with a robust feedback controller. This paper deals with the design and performance comparison of a conventional PID feedback controller with a fuzzy-based PID controller and suggests the most suitable controller. The design was implemented in real time through the dSPACE DS1104 controller environment to verify the dynamic behaviors of the arm.
Li, Jiaqiang; Choutko, Vitaly; Xiao, Liyi
2018-03-01
Based on the collection of error data from the Alpha Magnetic Spectrometer (AMS) Digital Signal Processors (DSP), on-orbit Single Event Upsets (SEUs) of the DSP program memory are analyzed. The daily error distribution and time intervals between errors are calculated to evaluate the reliability of the system. The particle density distribution of International Space Station (ISS) orbit is presented and the effects from the South Atlantic Anomaly (SAA) and the geomagnetic poles are analyzed. The impact of solar events on the DSP program memory is carried out combining data analysis and Monte Carlo simulation (MC). From the analysis and simulation results, it is concluded that the area corresponding to the SAA is the main source of errors on the ISS orbit. Solar events can also cause errors on DSP program memory, but the effect depends on the on-orbit particle density.
International Nuclear Information System (INIS)
Woodruff, W.R.; Bryan, J.B.
1978-01-01
Single-charge and row-charge subsurface cratering experiments were performed to learn how close-spacing enhances single-crater dimensions. Our first experimental phase established cratering curves for 60-lb charges of the chemical explosive. For the second phase, to be described in a subsequent report, the Row-cratering experiments were designed and executed. This data report contains excavated dimensions and auxiliary data for the single-charge cratering experiments. The dimensions for the row-charge experiments will be in the other report. Significant changes in the soil's water content appeared to cause a variability in the excavated dimensions. This variability clouded the interpretation and application of the cratering curves obtained
N=4 supersymmetry on a space-time lattice
DEFF Research Database (Denmark)
Catterall, Simon; Schaich, David; Damgaard, Poul H.
2014-01-01
Maximally supersymmetric Yang–Mills theory in four dimensions can be formulated on a space-time lattice while exactly preserving a single supersymmetry. Here we explore in detail this lattice theory, paying particular attention to its strongly coupled regime. Targeting a theory with gauge group SU...
Fractal Dimension in Epileptic EEG Signal Analysis
Uthayakumar, R.
Fractal Analysis is the well developed theory in the data analysis of non-linear time series. Especially Fractal Dimension is a powerful mathematical tool for modeling many physical and biological time signals with high complexity and irregularity. Fractal dimension is a suitable tool for analyzing the nonlinear behaviour and state of the many chaotic systems. Particularly in analysis of chaotic time series such as electroencephalograms (EEG), this feature has been used to identify and distinguish specific states of physiological function.Epilepsy is the main fatal neurological disorder in our brain, which is analyzed by the biomedical signal called Electroencephalogram (EEG). The detection of Epileptic seizures in the EEG Signals is an important tool in the diagnosis of epilepsy. So we made an attempt to analyze the EEG in depth for knowing the mystery of human consciousness. EEG has more fluctuations recorded from the human brain due to the spontaneous electrical activity. Hence EEG Signals are represented as Fractal Time Series.The algorithms of fractal dimension methods have weak ability to the estimation of complexity in the irregular graphs. Divider method is widely used to obtain the fractal dimension of curves embedded into a 2-dimensional space. The major problem is choosing initial and final step length of dividers. We propose a new algorithm based on the size measure relationship (SMR) method, quantifying the dimensional behaviour of irregular rectifiable graphs with minimum time complexity. The evidence for the suitability (equality with the nature of dimension) of the algorithm is illustrated graphically.We would like to demonstrate the criterion for the selection of dividers (minimum and maximum value) in the calculation of fractal dimension of the irregular curves with minimum time complexity. For that we design a new method of computing fractal dimension (FD) of biomedical waveforms. Compared to Higuchi's algorithm, advantages of this method include
Non-supersymmetric Attractors in Symmetric Coset Spaces
Li, Wei
We develop a method of constructing generic black hole attractor solutions, both BPS and non-BPS, single-centered as well as multi-centered, in a large class of 4D N = 2 supergravities coupled to vector-multiplets with cubic prepotentials. The method is applicable to models for which the 3D moduli spaces obtained via c ∗-map are symmetric coset spaces. All attractor solutions in such a 3D moduli space can be constructed algebraically in a unified way. Then the 3D attractor solutions are mapped back into four dimensions to give 4D extremal black holes.
DEFF Research Database (Denmark)
Frederiksen, Morten
2012-01-01
Georg Simmel is the seminal author on trust within sociology, but though inspired by Simmel, subsequent studies of intersubjective trust have failed to address Simmel’s suggestion that trust is as differentiated as the social relations of which it is part. Rather, trust has been studied within...... limited sets of exchange or work relations. This article revisits Simmel’s concept of trust as social form in order to investigate this differentiation. From an interview study, the differentiation and limits of trust are analysed within different types of social relations. Trust is found to vary greatly...... in scope and mode influenced by the intersecting dimensions of relations, objects and situations. Furthermore, trust exists between an outer threshold of expected deceit and an inner threshold of confident reliance. The findings from the qualitative study contribute new knowledge on the diversity of trust...
Phenomenology of Extra Dimensions
Energy Technology Data Exchange (ETDEWEB)
Hewett, J.L.; /SLAC
2006-11-07
If the structure of spacetime is different than that readily observed, gravitational physics, particle physics and cosmology are all immediately affected. The physics of extra dimensions offers new insights and solutions to fundamental questions arising in these fields. Novel ideas and frameworks are continuously born and evolved. They make use of string theoretical features and tools and they may reveal if and how the 11-dimensional string theory is relevant to our four-dimensional world. We have outlined some of the experimental observations in particle and gravitational physics as well as astrophysical and cosmological considerations that can constrain or confirm these scenarios. These developing ideas and the wide interdisciplinary experimental program that is charted out to investigate them mark a renewed effort to describe the dynamics behind spacetime. We look forward to the discovery of a higher dimensional spacetime.
Directory of Open Access Journals (Sweden)
Uzelac Nikola
2004-01-01
Full Text Available Time dimension of marketing has got its place in literature. For example, the time is basic independent variable in widely accepted concepts of product life cycle and diffusion of innovation. In addition, efforts have been made to bring this issue to the theoretic basis of the discipline. But, some important areas are still under researched, or even disregarded. Moreover, projects directed at investigation of the real behavior of marketing managers are rare, and in normative sense very few options have been advocated. This particularly pertains to the issues of time horizon, durability of relations with customers, timeliness of decision-making, and time allocation by managers and customers. In this regard, the literature of strategic management contains solutions which might be useful, and the ideas of some authors from marketing deserve support.
Oberlack, M.; McComb, W. D.; Quinn, A. P.
2001-02-01
It is shown that the set of integrodifferential and algebraic functional equations of the local energy transfer theory may be considerably reduced in dimension for the case of isotropic turbulence. This is achieved without restricting the solution space. The basis for this is a complete analytical solution to the functional equations Q(kt,t')=H(kt,t')Q(kt',t') and H(kt,s)H(ks,t')=H(kt,t'). The solution is proved to depend only on a single function φ(kt) solely determining Q and H. Hence the dimension of both the dependent and the independent variables is reduced by one. From the latter, the corresponding two integrodifferential equations are lowered to a single integrodifferential equation for φ(kt), extended by an integral side condition on the k dependence of φ(kt). In the limit ν-->0, a partial solution to the reduced set of equations is presented in the Appendix.
Emergent spacetime in stochastically evolving dimensions
Directory of Open Access Journals (Sweden)
Niayesh Afshordi
2014-12-01
Full Text Available Changing the dimensionality of the space–time at the smallest and largest distances has manifold theoretical advantages. If the space is lower dimensional in the high energy regime, then there are no ultraviolet divergencies in field theories, it is possible to quantize gravity, and the theory of matter plus gravity is free of divergencies or renormalizable. If the space is higher dimensional at cosmological scales, then some cosmological problems (including the cosmological constant problem can be attacked from a completely new perspective. In this paper, we construct an explicit model of “evolving dimensions” in which the dimensions open up as the temperature of the universe drops. We adopt the string theory framework in which the dimensions are fields that live on the string worldsheet, and add temperature dependent mass terms for them. At the Big Bang, all the dimensions are very heavy and are not excited. As the universe cools down, dimensions open up one by one. Thus, the dimensionality of the space we live in depends on the energy or temperature that we are probing. In particular, we provide a kinematic Brandenberger–Vafa argument for how a discrete causal set, and eventually a continuum (3+1-dim spacetime along with Einstein gravity emerges in the Infrared from the worldsheet action. The (3+1-dim Planck mass and the string scale become directly related, without any compactification. Amongst other predictions, we argue that LHC might be blind to new physics even if it comes at the TeV scale. In contrast, cosmic ray experiments, especially those that can register the very beginning of the shower, and collisions with high multiplicity and density of particles, might be sensitive to the dimensional cross-over.
Flatland a romance of many dimensions
Abbott, Edwin Abbott
2015-01-01
In 1884, Edwin Abbott Abbott wrote a mathematical adventure set in a two-dimensional plane world, populated by a hierarchical society of regular geometrical figures-who think and speak and have all too human emotions. Since then Flatland has fascinated generations of readers, becoming a perennial science-fiction favorite. By imagining the contact of beings from different dimensions, the author fully exploited the power of the analogy between the limitations of humans and those of his two-dimensional characters. A first-rate fictional guide to the concept of multiple dimensions of space, the book will also appeal to those who are interested in computer graphics. This field, which literally makes higher dimensions seeable, has aroused a new interest in visualization. We can now manipulate objects in four dimensions and observe their three-dimensional slices tumbling on the computer screen. But how do we interpret these images? In his introduction, Thomas Banchoff points out that there is no better way to begin ...
Hayward, O. T.; And Others
This publication is one of a series of single-topic problem modules designed for use in undergraduate geology and earth science courses. The first section, "Ain't It Flat? A Series of Experiments in Geodesy," presents various experiments for determining the earth's circumference (historically) and describes the use of satellites in determining the…
Vertical dimensions of suspended horses.
Clutton, R E; Chase-Topping, M; Squires, R; Lawson, H; Minard, H; Rose, S
2010-11-01
The dimensions of anaesthetised hobbled horses during suspension and transfer onto the operating table are unknown. These data are required for the cost-effective construction of equine surgical facilities. To measure the distance from the toe to dependent back margin (Bsusp) and poll (Psusp) of anaesthetised suspended horses and correlate them with readily obtained measures from standing animals. Digital photographs of suspended horses were taken in the anaesthesia induction box at a fixed position that allowed trigonometric determination of Bsusp and Psusp. These values were linked with body mass, height at the withers (Wstand), the length of the crest from the poll to the withers (crest) and of the back (back) from the withers to the crop, by deriving an equine morphological index (EMI) using principal component analysis. The EMI and other linear variables were then subjected to single variable regression analysis. EMI was 0.531mass((kg)) + 0.528Wstand((cm)) + 0.469crest((cm)) + 0.468back((cm)) . Bsusp was most accurately estimated using the expression Bsusp= 118.71 + 0.128EMI while Psusp was most strongly associated with Wstand, i.e. Psusp= 46.9 + 1.01Wstand((cm)) . The height of suspended horses at the most ventral margin of the back and the poll can be estimated from measures taken from the standing animal. The data will allow the more informed planning and construction of equine surgical facilities in which mechanical hoists are used. © 2010 EVJ Ltd.
Dimensions of ecosystem theory
International Nuclear Information System (INIS)
O'Neill, R.V.; Reichle, D.E.
1979-01-01
Various dimensions of ecosystem structure and behavior that seem to develop from the ubiquitous phenomena of system growth and persistence were studied. While growth and persistence attributes of ecosystems may appear to be simplistic phenomena upon which to base a comprehensive ecosystem theory, these same attributes have been fundamental to the theoretical development of other biological disciplines. These attributes were explored at a hierarchical level in a self-organizing system, and adaptive system strategies that result were analyzed. Previously developed causative relations (Reichle et al., 1975c) were examined, their theoretical implications expounded upon, and the assumptions tested with data from a variety of forest types. The conclusions are not a theory in themselves, but a state of organization of concepts contributing towards a unifying theory, along the lines promulgated by Bray (1958). The inferences drawn rely heavily upon data from forested ecosystems of the world, and have yet to be validated against data from a much more diverse range of ecosystem types. Not all of the interpretations are logically tight - there is room for other explanations, which it is hoped will provide fruitful grounds for further speculation
Analytical estimation of the correlation dimension of integer lattices.
Lacasa, Lucas; Gómez-Gardeñes, Jesús
2014-12-01
Recently [L. Lacasa and J. Gómez-Gardeñes, Phys. Rev. Lett. 110, 168703 (2013)], a fractal dimension has been proposed to characterize the geometric structure of networks. This measure is an extension to graphs of the so called correlation dimension, originally proposed by Grassberger and Procaccia to describe the geometry of strange attractors in dissipative chaotic systems. The calculation of the correlation dimension of a graph is based on the local information retrieved from a random walker navigating the network. In this contribution, we study such quantity for some limiting synthetic spatial networks and obtain analytical results on agreement with the previously reported numerics. In particular, we show that up to first order, the correlation dimension β of integer lattices ℤ(d) coincides with the Haussdorf dimension of their coarsely equivalent Euclidean spaces, β = d.
Directory of Open Access Journals (Sweden)
Dimitrios V Vavoulis
Full Text Available Traditional approaches to the problem of parameter estimation in biophysical models of neurons and neural networks usually adopt a global search algorithm (for example, an evolutionary algorithm, often in combination with a local search method (such as gradient descent in order to minimize the value of a cost function, which measures the discrepancy between various features of the available experimental data and model output. In this study, we approach the problem of parameter estimation in conductance-based models of single neurons from a different perspective. By adopting a hidden-dynamical-systems formalism, we expressed parameter estimation as an inference problem in these systems, which can then be tackled using a range of well-established statistical inference methods. The particular method we used was Kitagawa's self-organizing state-space model, which was applied on a number of Hodgkin-Huxley-type models using simulated or actual electrophysiological data. We showed that the algorithm can be used to estimate a large number of parameters, including maximal conductances, reversal potentials, kinetics of ionic currents, measurement and intrinsic noise, based on low-dimensional experimental data and sufficiently informative priors in the form of pre-defined constraints imposed on model parameters. The algorithm remained operational even when very noisy experimental data were used. Importantly, by combining the self-organizing state-space model with an adaptive sampling algorithm akin to the Covariance Matrix Adaptation Evolution Strategy, we achieved a significant reduction in the variance of parameter estimates. The algorithm did not require the explicit formulation of a cost function and it was straightforward to apply on compartmental models and multiple data sets. Overall, the proposed methodology is particularly suitable for resolving high-dimensional inference problems based on noisy electrophysiological data and, therefore, a
Dictionary-based output-space dimensionality reduction
Strasser, Pablo; Wang, Jung; Armand, Stéphane; Kalousis, Alexandros
2013-01-01
In this paper we propose a method for output dimensionality reduction based on dictionary learning. Our final goal is the prediction of complete time series from standard input vectorial data. To do so we formulate a single learning problem which on the one hand learns a new representation of the output space, using dictionary learning, and reduces its dimension, while on the other hand learns to predict from the input data the new output representation, using standard multi-output regression...
Directory of Open Access Journals (Sweden)
Ryabov Yury
2012-01-01
Full Text Available The creation of an area of freedom, security and justice is one of the most rapidly developing aspects of European integration. It this paper, we take a look at the foreign policies involved in this process — aside from the internal development of the European Union, they concern a significant number of third countries, including Russia. In our view, the efforts to manage the flow of migrants and asylum seekers constitute a viable part of the external dimension within the AFSJ policies. Much of this article is based on the theoretical postulates introduced by the scholars of the Paris School, a school within the discipline of security studies that conceptualized the connection between migration, terrorism, asylum, crime and ethnic clashes, and its role as a major threat facing the European Union. Externalization of this complex threat (that is, externalization in relation to the European Union is thus seen as one of the key prerequisites to advancement of migration management activities beyond the EU (i. e. externalization of migration management. In this article, we analyze the role the EU plays at the international scene and categorize the actions it took to manage the influx of migrants and asylum seekers from the 1980s until the time when supranational administrative bodies were granted mandates in the spheres of Justice and Home Affairs (JHA of the EU Member States. We conclude that it was as early as the 1990-s that th
Hájek, Tomáš; Jandera, Pavel
2012-07-01
Gradient elution provides significantly higher peak capacity in comparison to the isocratic elution mode, hence it is very useful in online comprehensive two-dimensional liquid chromatography (LC). We compared suitability of five commercial core-shell columns and one monolithic column for fast gradients in the second LC dimension, where the time of separation is strictly limited by the fraction cycle time. In two-dimensional reversed-phase systems with partially correlated retention, the resolution, the peak capacity, and the regularity of coverage of the second-dimension retention space can be improved by appropriate adjusting the gradient time and the gradient range to suit the sample properties. We developed a new strategy for adjusting the gradient mobile phase composition range in the second-dimension, employing the retention data of representative sample standards characterizing the sample properties, which can be calibrated using the reference alkylbenzene series. Optimized second-dimension gradients with single-step or segmented profiles covering two or more fraction ranges, employed for the separation of subsequent fractions from the first-dimension, improve significantly the resolution, the separation time, and the regularity of coverage of the two-dimensional retention plane. The approach was applied to the two-dimensional comprehensive separation of phenolic acids and flavonoid compounds occurring as natural antioxidants. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Grandes nouvelles dimensions et gravité quantique au coin
Arkani-Hamed, Nima; Dimopoulos, Savas; Dvali, Gia
2003-04-01
The electroweak unification mass may be the only fundamental scale in nature. If so, the visible universe may lie on a membrane floating within a higher dimensional space; new dimensions, black holes, quantum gravity, and string theory may become experimentally accessible in this decade. The dark matter could reside on parallel universes inside the extra dimensions. To cite this article: N. Arkani-Hamed et al., C. R. Physique 4 (2003).
Discrete quantum geometries and their effective dimension
International Nuclear Information System (INIS)
Thuerigen, Johannes
2015-01-01
In several approaches towards a quantum theory of gravity, such as group field theory and loop quantum gravity, quantum states and histories of the geometric degrees of freedom turn out to be based on discrete spacetime. The most pressing issue is then how the smooth geometries of general relativity, expressed in terms of suitable geometric observables, arise from such discrete quantum geometries in some semiclassical and continuum limit. In this thesis I tackle the question of suitable observables focusing on the effective dimension of discrete quantum geometries. For this purpose I give a purely combinatorial description of the discrete structures which these geometries have support on. As a side topic, this allows to present an extension of group field theory to cover the combinatorially larger kinematical state space of loop quantum gravity. Moreover, I introduce a discrete calculus for fields on such fundamentally discrete geometries with a particular focus on the Laplacian. This permits to define the effective-dimension observables for quantum geometries. Analysing various classes of quantum geometries, I find as a general result that the spectral dimension is more sensitive to the underlying combinatorial structure than to the details of the additional geometric data thereon. Semiclassical states in loop quantum gravity approximate the classical geometries they are peaking on rather well and there are no indications for stronger quantum effects. On the other hand, in the context of a more general model of states which are superposition over a large number of complexes, based on analytic solutions, there is a flow of the spectral dimension from the topological dimension d on low energy scales to a real number between 0 and d on high energy scales. In the particular case of 1 these results allow to understand the quantum geometry as effectively fractal.
Unified theories from fuzzy extra dimensions
International Nuclear Information System (INIS)
Aschieri, P.; Madore, J.; Manousselis, P.; Zoupanos, G.
2004-01-01
We combine and exploit ideas from Coset Space Dimensional Reduction (CSDR) methods and Non-commutative Geometry. We consider the dimensional reduction of gauge theories defined in high dimensions where the compact directions are a fuzzy space (matrix manifold). In the CSDR one assumes that the form of space-time is M D =M 4 x S/R with S/R a homogeneous space. Then a gauge theory with gauge group G defined on M D can be dimensionally reduced to M 4 in an elegant way using the symmetries of S/R, in particular the resulting four dimensional gauge is a subgroup of G. In the present work we show that one can apply the CSDR ideas in the case where the compact part of the space-time is a finite approximation of the homogeneous space S/R, i.e. a fuzzy coset. In particular we study the fuzzy sphere case. (Abstract Copyright [2004], Wiley Periodicals, Inc.)
A distinguishing gravitational property for gravitational equation in higher dimensions
International Nuclear Information System (INIS)
Dadhich, Naresh
2016-01-01
It is well known that Einstein gravity is kinematic (meaning that there is no non-trivial vacuum solution; i.e. the Riemann tensor vanishes whenever the Ricci tensor does so) in 3 dimension because the Riemann tensor is entirely given in terms of the Ricci tensor. Could this property be universalized for all odd dimensions in a generalized theory? The answer is yes, and this property uniquely singles out pure Lovelock (it has only one Nth order term in the action) gravity for which the Nth order Lovelock-Riemann tensor is indeed given in terms of the corresponding Ricci tensor for all odd, d = 2N + 1, dimensions. This feature of gravity is realized only in higher dimensions and it uniquely picks out pure Lovelock gravity from all other generalizations of Einstein gravity. It serves as a good distinguishing and guiding criterion for the gravitational equation in higher dimensions. (orig.)
Gravitating multidefects from higher dimensions
Giovannini, Massimo
2007-01-01
Warped configurations admitting pairs of gravitating defects are analyzed. After devising a general method for the construction of multidefects, specific examples are presented in the case of higher-dimensional Einstein-Hilbert gravity. The obtained profiles describe diverse physical situations such as (topological) kink-antikink systems, pairs of non-topological solitons and bound configurations of a kink and of a non-topological soliton. In all the mentioned cases the geometry is always well behaved (all relevant curvature invariants are regular) and tends to five-dimensional anti-de Sitter space-time for large asymptotic values of the bulk coordinate. Particular classes of solutions can be generalized to the framework where the gravity part of the action includes, as a correction, the Euler-Gauss-Bonnet combination. After scrutinizing the structure of the zero modes, the obtained results are compared with conventional gravitating configurations containing a single topological defect.
Anomalous Dimensions of Conformal Baryons
DEFF Research Database (Denmark)
Pica, Claudio; Sannino, Francesco
2016-01-01
We determine the anomalous dimensions of baryon operators for the three color theory as function of the number of massless flavours within the conformal window to the maximum known order in perturbation theory. We show that the anomalous dimension of the baryon is controllably small, within...
Physics with large extra dimensions
Indian Academy of Sciences (India)
Furthermore, our world must be confined to live on a brane transverse to these large dimensions, with which it ... this scenario which gives a new theoretical framework for solving the gauge hierarchy problem and the ... of the possible existence of extra dimensions accessible to future accelerators [2]. The main theoretical ...
Saliency of social comparison dimensions
Kuyper, H.
2007-01-01
The present article discusses a theory of the saliency of social comparison dimensions and presents the results of an experiment about the effects of two different experimental situations on the saliency of exterior, task-related and socio-emotional dimensions. Saliency was operationalized with a
Mathematics Teachers' Criteria of Dimension
Ural, Alattin
2014-01-01
The aim of the study is to determine mathematics teachers' decisions about dimensions of the geometric figures, criteria of dimension and consistency of decision-criteria. The research is a qualitative research and the model applied in the study is descriptive method on the basis of general scanning model. 15 mathematics teachers attended the…
Beta Function and Anomalous Dimensions
DEFF Research Database (Denmark)
Pica, Claudio; Sannino, Francesco
2011-01-01
We demonstrate that it is possible to determine the coefficients of an all-order beta function linear in the anomalous dimensions using as data the two-loop coefficients together with the first one of the anomalous dimensions which are universal. The beta function allows to determine the anomalous...
supersymmetry breaking with extra dimensions
Indian Academy of Sciences (India)
mechanism for (super)symmetry breaking, proposed first by Scherk and Schwarz, where extra dimensions play a crucial role. The last part is devoted to the description of some recent results and of some open problems. Keywords. Supersymmetry; supergravity; extra dimensions. PACS Nos 11.25.Мj; 11.25.Wx; 11.25.
supersymmetry breaking with extra dimensions
Indian Academy of Sciences (India)
This talk reviews some aspects of supersymmetry breaking in the presence of extra dimensions. The first part is a general introduction, recalling the motivations for supersymmetry and extra dimensions, as well as some unsolved problems of four-dimensional models of supersymmetry breaking. The central part is a more ...
An introduction to extra dimensions
International Nuclear Information System (INIS)
Perez-Lorenzana, Abdel
2005-01-01
Models that involve extra dimensions have introduced completely new ways of looking up on old problems in theoretical physics. The aim of the present notes is to provide a brief introduction to the many uses that extra dimensions have found over the last few years, mainly following an effective field theory point of view. Most parts of the discussion are devoted to models with flat extra dimensions, covering both theoretical and phenomenological aspects. We also discuss some of the new ideas for model building where extra dimensions may play a role, including symmetry breaking by diverse new and old mechanisms. Some interesting applications of these ideas are discussed over the notes, including models for neutrino masses and proton stability. The last part of this review addresses some aspects of warped extra dimensions, and graviton localization
Geography From Another Dimension
2002-01-01
The GEODESY software program is intended to promote geographical awareness among students with its remote sensing capabilities to observe the Earth's surface from distant vantage points. Students and teachers using GEODESY learn to interpret and analyze geographical data pertaining to the physical attributes of their community. For example, the program provides a digital environment of physical features, such as mountains and bodies of water, as well as man-made features, such as roads and parks, using aerial photography, satellite imagery, and geographic information systems data in accordance with National Geography Standards. The main goal is to have the students and teachers gain a better understanding of the unique forces that drive their coexistence. GEODESY was developed with technical assistance and financial support from Stennis Space Center's Commercial Remote Sensing Program Office, now known as the Earth Science Applications Directorate.
Quantum gravity in more than four dimensions
International Nuclear Information System (INIS)
Vaz, C.
1987-01-01
Ever since its inception, Einstein's general relativity has been considered a most remarkable theory. It is generally believed today, that the classical theory is well understood. Nevertheless, in the pursuit of a deeper understanding of physics in terms of a grand unification of forces, one would like to quantize the theory, thus bringing it under the known forces of nature. The author will address the possibility that space-time is of dimension greater that four. In the pursuit of Einstein's dream of a unification of physical interactions, many interesting ideas have been developed. Beginning with Weyl and Kaluza, we have progressed to strings and superstrings. The thing that is common to all these theories is the requirement of a space-time of more than four dimensions. While Kaluza's theory implicitly assumes that Einstein's gravity is classically correct in any number of dimensions, superstring phenomenology may suggest otherwise. Generalizations to Einstein's gravity are indicated, and the gravitational Casimir energy is explicitly approximate on a background configuration M 4 x S 6 , on a ten dimensional space-time. Weyl invariance is particularly interesting to the quantum gravitationalist. One finds that energy momentum tensor of the Weyl invariant quantum field picks up an anomalous trace, which is related to particle production by the curved background. He therefore computes the conformal anomaly for a conformally coupled scalar field and considers some of its consequences. He then suggest that the conformal anomaly, when combined with the perfect fluid hypothesis, can be used to determine the complete energy momentum tensor of the quantum field in certain backgrounds
Amir-Moez, A R; Sneddon, I N
1962-01-01
Elements of Linear Space is a detailed treatment of the elements of linear spaces, including real spaces with no more than three dimensions and complex n-dimensional spaces. The geometry of conic sections and quadric surfaces is considered, along with algebraic structures, especially vector spaces and transformations. Problems drawn from various branches of geometry are given.Comprised of 12 chapters, this volume begins with an introduction to real Euclidean space, followed by a discussion on linear transformations and matrices. The addition and multiplication of transformations and matrices a
Signatures of extra dimensions in gravitational waves
Energy Technology Data Exchange (ETDEWEB)
Andriot, David; Gómez, Gustavo Lucena, E-mail: andriotphysics@gmail.com, E-mail: glucenag@aei.mpg.de [Max-Planck-Institut für Gravitationsphysik, Albert-Einstein-Institut, Am Mühlenberg 1, 14467 Potsdam-Golm (Germany)
2017-06-01
Considering gravitational waves propagating on the most general 4+ N -dimensional space-time, we investigate the effects due to the N extra dimensions on the four-dimensional waves. All wave equations are derived in general and discussed. On Minkowski{sub 4} times an arbitrary Ricci-flat compact manifold, we find: a massless wave with an additional polarization, the breathing mode, and extra waves with high frequencies fixed by Kaluza-Klein masses. We discuss whether these two effects could be observed.
Dimension-Independent Likelihood-Informed MCMC
Cui, Tiangang
2015-01-07
Many Bayesian inference problems require exploring the posterior distribution of high-dimensional parameters, which in principle can be described as functions. By exploiting low-dimensional structure in the change from prior to posterior [distributions], we introduce a suite of MCMC samplers that can adapt to the complex structure of the posterior distribution, yet are well-defined on function space. Posterior sampling in nonlinear inverse problems arising from various partial di erential equations and also a stochastic differential equation are used to demonstrate the e ciency of these dimension-independent likelihood-informed samplers.
Geometry, relativity and the fourth dimension
Rucker, Rudolf
1977-01-01
This is a highly readable, popular exposition of the fourth dimension and the structure of the universe. A remarkable pictorial discussion of the curved space-time we call home, it achieves even greater impact through the use of 141 excellent illustrations. This is the first sustained visual account of many important topics in relativity theory that up till now have only been treated separately.Finding a perfect analogy in the situation of the geometrical characters in Flatland, Professor Rucker continues the adventures of the two-dimensional world visited by a three-dimensional being to expl
Dimensionality reduction for dimension-specific search
Huang, Zi; Hengtao, Shen; Zhou, Xiaofang; Song, Dawei; Rüger, Stefan
2007-01-01
Dimensionality reduction plays an important role in efficient similarity search, which is often based on k-nearest neighbor (k-NN) queries over a high-dimensional feature space. In this paper, we introduce a novel type of k-NN query, namely conditional k-NN (ck-NN), which considers dimension-specific constraint in addition to the inter-point distances. However, existing dimensionality reduction methods are not applicable to this new type of queries. We propose a novel Mean-Std (standard devia...
Extra Dimensions A View from the Top
Lola, S; Raychaudhuri, S; Sridhar, K; Lola, Smaragda; Mathews, Prakash; Raychaudhuri, Sreerup
2011-01-01
In models with compact extra dimensions, where the Standard Model fields are confined to a 3+1 dimensional hyperplane, the $t \\bar t$ production cross-section at a hadron collider can receive significant contributions from multiple exchange of KK modes of the graviton. These are carefully computed in the well-known ADD and RS scenarios, taking the energy dependence of the sum over graviton propagators into account. Using data from Run-I of the Tevatron, 95% C.L. bounds on the parameter space of both models are derived. For Run-II of the Tevatron and LHC, discovery limits are estimated.
Liu, Ju-Yan; Wang, Qian; Zhang, Li-Jun; Yuan, Bin; Xu, Yao-Yao; Zhang, Xin; Zhao, Cong-Ying; Wang, Dan; Yuan, Yue; Wang, Ying; Ding, Bin; Zhao, Xiao-Jun; Yue, Min Min
2014-06-16
A new multidentate ligand 1-(9-(1H-1,2,4-triazol-1-yl)anthracen-10-yl)-1H-1,2,4-triazole (tatrz) was designed and synthesized. Using tatrz as a building block, three novel coordination frameworks, namely, {[Cu(tatrz)2(NO3)2]·(CH3OH)·4H2O}n (1), {[Cu(tatrz)2(H2O)2](BF4)2}n (2), and [Mn(tatrz)2(SCN)2(CH3OH)]·2H2O (3) can be isolated. Anion-exchange experiment indicates that NO3(-) anions in the two-dimensional (2D) copper framework of 1 can be completely exchanged by ClO4(-) in an irreversible single crystal-to-single crystal (SC-SC) transformation fashion, as evidenced by the anion-exchange products of {[Cu(tatrz)2(H2O)2](ClO4)2·4CH3OH} (1a). Further, if 1a was employed as a precursor in N,N-dimethylformamide (DMF), an isomorphic solvate of {[Cu(tatrz)2(DMF)2](ClO4)2·2H2O}n (1b) can be generated during the reversible dynamic transformation process. When 1 was immersed in CH3OH, a distinct 2D layer {[Cu(tatrz)2(NO3)2]·4.4CH3OH·0.6H2O}n (1c) was isolated. Interestingly, the solvent-exchange conversion is also invertible between 1 and 1c, which exhibits spongelike dynamic behavior with retention of crystalline integrity. If the 2-fold interpenetrating three-dimensional (3D) framework 2 is selected, it can be transformed into another 2-fold interpenetrating 3D framework {[Cu(tatrz)2(H2O)2](ClO4)2·5.56H2O}n (2a) in a reversible SC-SC transformation fashion. However, when the light yellow crystals of mononuclear complex 3 were exposed to trichloromethane containing aromatic organic anthracene (atan), through our careful observation, the crystals of 3 were dissolved and reassembled into dark brown crystals of 2D crystalline coordination framework {[Mn(tatrz)2(SCN)2]·(atan)}n (3a). X-ray diffraction revealed that in 3a, atan acting as an organic template was encapsulated in the confined space of the 2D grid. Luminescent measurements illustrate that 3a is the first report of multidimensional polymers based on triazole derivatives as luminescent probes of Mg(2+).
Thermal dimension of quantum spacetime
Energy Technology Data Exchange (ETDEWEB)
Amelino-Camelia, Giovanni, E-mail: amelino@roma1.infn.it [Dipartimento di Fisica, Università “La Sapienza” and Sez. Roma1 INFN, P.le A. Moro 2, 00185 Roma (Italy); Brighenti, Francesco [Theoretical Physics, Blackett Laboratory, Imperial College, London, SW7 2BZ (United Kingdom); Dipartimento di Fisica e Astronomia dell' Università di Bologna and Sez. Bologna INFN, Via Irnerio 46, 40126 Bologna (Italy); Gubitosi, Giulia [Theoretical Physics, Blackett Laboratory, Imperial College, London, SW7 2BZ (United Kingdom); Santos, Grasiele [Dipartimento di Fisica, Università “La Sapienza” and Sez. Roma1 INFN, P.le A. Moro 2, 00185 Roma (Italy)
2017-04-10
Recent results suggest that a crucial crossroad for quantum gravity is the characterization of the effective dimension of spacetime at short distances, where quantum properties of spacetime become significant. This is relevant in particular for various scenarios of “dynamical dimensional reduction” which have been discussed in the literature. We are here concerned with the fact that the related research effort has been based mostly on analyses of the “spectral dimension”, which involves an unphysical Euclideanization of spacetime and is highly sensitive to the off-shell properties of a theory. As here shown, different formulations of the same physical theory can have wildly different spectral dimension. We propose that dynamical dimensional reduction should be described in terms of the “thermal dimension” which we here introduce, a notion that only depends on the physical content of the theory. We analyze a few models with dynamical reduction both of the spectral dimension and of our thermal dimension, finding in particular some cases where thermal and spectral dimension agree, but also some cases where the spectral dimension has puzzling properties while the thermal dimension gives a different and meaningful picture.
DEFF Research Database (Denmark)
Hu, Hao; Ye, Feihong; Medhin, Ashenafi Kiros
2014-01-01
We demonstrate 43-Tbit/s transmission over 67.4-km seven-core fiber using a single source. Each of the 6 outer cores carries 6 Nyquist-WDM channels using 320-Gbaud Nyquist- OTDM-PDM-QPSK 330-GHz spaced, and the center core carries 10-GHz clock pulses....
DEFF Research Database (Denmark)
Hu, Hao; Ye, Feihong; Medhin, Ashenafi Kiros
2014-01-01
We demonstrate 43-Tbit/s transmission over 67.4-km seven-core fiber using a single source. Each of the 6 outer cores carries 6 Nyquist-WDM channels using 320-Gbaud Nyquist- OTDM-PDM-QPSK 330-GHz spaced, and the center core carries 10-GHz clock pulses....
Mass generation and related issues from exotic higher dimensions
International Nuclear Information System (INIS)
Colatto, Luiz Paulo; Andrade, Marco Antonio de; Assis, Leonardo Paulo Guimaraes de; Helayel-Neto, Jose Abdalla; Rojas, Moises
2011-01-01
Full text: he main purpose of this work is to show that massless Dirac equation formulated for non-interacting Majorana-Weyl spinors in higher dimensions, particularly in D = 1 + 9 and D = 5 + 5, may yield to an interpretation of massive Majorana and Dirac spinors in D = 1 + 3 dimensions. The particular case of a dimensional reduction from D = 4 + 4 to D = 1 + 3 has already been fairly-well discussed in the literature. By adopting suitable representations of the Dirac matrices in higher dimensions, we pursue the investigation of which higher dimensional space-times and which metric signatures concerning massless Dirac equations in highermay induce massive spinors in D = 1+3 dimensions. The mixing of the chiral fermions in higher dimensions may induce a mechanism such that four massive Majorana fermions may show up and, at an appropriate limit an almost zero and a huge mass show up with corresponding left-handed and right-handed eigenstates. This mechanism could reassess a peculiar connection with the See-Saw scheme associated to neutrino with Majorana-type masses. The masses of the particle are fixed by the dimensional reduction scheme, which the decoupled dimensions contribute coordinates and depend on the mass invariants in lower dimensions. This proposal should allow us to understand the generation of hierarchies for the fermionic masses in D = 1 + 3, or in lower dimensions in general, starting from the constraints between the energy and the momentum in (n; n) dimensions. For the initial D = 5 + 5 Majorana-Weyl spinors framework using the Weyl representation to the Dirac matrices we observe an intriguing decomposition of space-time that result in two equivalent D = 1 + 4 massive spinors which mass term, in D = 1 + 3 included, is originated from the remained component and that could induce a Brane-World mechanism. (author)
Phase space methods for degenerate quantum gases
Dalton, Bryan J; Barnett, Stephen M
2015-01-01
Recent experimental progress has enabled cold atomic gases to be studied at nano-kelvin temperatures, creating new states of matter where quantum degeneracy occurs - Bose-Einstein condensates and degenerate Fermi gases. Such quantum states are of macroscopic dimensions. This book presents the phase space theory approach for treating the physics of degenerate quantum gases, an approach already widely used in quantum optics. However, degenerate quantum gases involve massive bosonic and fermionic atoms, not massless photons. The book begins with a review of Fock states for systems of identical atoms, where large numbers of atoms occupy the various single particle states or modes. First, separate modes are considered, and here the quantum density operator is represented by a phase space distribution function of phase space variables which replace mode annihilation, creation operators, the dynamical equation for the density operator determines a Fokker-Planck equation for the distribution function, and measurable...
Singular Dimensions of theN= 2 Superconformal Algebras. I
Dörrzapf, Matthias; Gato-Rivera, Beatriz
Verma modules of superconfomal algebras can have singular vector spaces with dimensions greater than 1. Following a method developed for the Virasoro algebra by Kent, we introduce the concept of adapted orderings on superconformal algebras. We prove several general results on the ordering kernels associated to the adapted orderings and show that the size of an ordering kernel implies an upper limit for the dimension of a singular vector space. We apply this method to the topological N= 2 algebra and obtain the maximal dimensions of the singular vector spaces in the topological Verma modules: 0, 1, 2 or 3 depending on the type of Verma module and the type of singular vector. As a consequence we prove the conjecture of Gato-Rivera and Rosado on the possible existing types of topological singular vectors (4 in chiral Verma modules and 29 in complete Verma modules). Interestingly, we have found two-dimensional spaces of singular vectors at level 1. Finally, by using the topological twists and the spectral flows, we also obtain the maximal dimensions of the singular vector spaces for the Neveu-Schwarz N= 2 algebra (0, 1 or 2) and for the Ramond N= 2 algebra (0, 1, 2 or 3).
ANTHROPOLOGY DIMENSIONS AS INDEPENDENT AEROBIC ENDURANCE
Directory of Open Access Journals (Sweden)
Ratko Pavlović
2009-11-01
Full Text Available Endurance as human capability is treated in two ways. Some authors define it as mobility capability, while others deny this theory. The denying of this theory lies in attitude that endurance is saturated with psychological factors (motivation and cardio- vascular factors as well and is often identified with aero power, typical dimension of fun- ctional diagnostics. Having that in mind this research enabled the obtaining of necessary informations which could contribute to the clearing up of these uncoordinated opinions. The research included 110 student of the III year Phisical Education in East Sarajevo, male gender. Nine (9 predictors has been applied (4 variables for mobility space estima- te, 5 variables for morphology and functional space estimate and variable used for the estimate of endurance race 1500m. Obtained results confirmed statistical significance of two functional capability variable of Harvard step test, Margarija test and mobility variable race 4x15 meters with the race results.
On the UV Dimensions of Loop Quantum Gravity
Directory of Open Access Journals (Sweden)
Michele Ronco
2016-01-01
Full Text Available Planck-scale dynamical dimensional reduction is attracting more and more interest in the quantum-gravity literature since it seems to be a model independent effect. However, different studies base their results on different concepts of space-time dimensionality. Most of them rely on the spectral dimension; others refer to the Hausdorff dimension; and, very recently, the thermal dimension has also been introduced. We here show that all these distinct definitions of dimension give the same outcome in the case of the effective regime of Loop Quantum Gravity (LQG. This is achieved by deriving a modified dispersion relation from the hypersurface-deformation algebra with quantum corrections. Moreover, we also observe that the number of UV dimensions can be used to constrain the ambiguities in the choice of these LQG-based modifications of the Dirac space-time algebra. In this regard, introducing the polymerization of connections, that is, K→sinδK/δ, we find that the leading quantum correction gives dUV=2.5. This result may indicate that the running to the expected value of two dimensions is ongoing, but it has not been completed yet. Finding dUV at ultrashort distances would require going beyond the effective approach we here present.
Keynote speech: Dimensions of Change
DEFF Research Database (Denmark)
Jørgensen, Kenneth Mølbjerg
2004-01-01
The presentation seeks to construct a framework for understanding knowledge and knowledge work. I argue that knowledge may be understood as a social construction of reality. I argue that people construct their reality by integrating four dimensions of reality: Facts, logic, values and communicati...... introduce a basic framework for understanding knowledge. This is done by means of Wittgenstein's concept of language games. Second, I introduce the four dimensions of reality. Third I relate the model to the disciplines organizational learning and knowledge management...
Occlusal vertical dimension. Review article
Alvítez Temoche, Daniel Augusto; Facultad de Odontología de la Universidad Nacional Mayor de San Marcos.
2016-01-01
Modication of occlusal vertical dimension is a procedure that is often necessary for complex oral reha-bilitation treatments to get a functional occlusal for patients. is literature review was made on databases: Medline (PubMed), Scopus, Scielo, BSV (Bireme), ISI (Web of science) and Lilacs using the keywords “occlusal vertical dimension”,”altered vertical dimension”, “temporomandibular joint”, and “masticatory muscles”. It can be said that the management of occlusal vertical dimension is a s...
European accelerator facilities for single event effects testing
Energy Technology Data Exchange (ETDEWEB)
Adams, L.; Nickson, R.; Harboe-Sorensen, R. [ESA-ESTEC, Noordwijk (Netherlands); Hajdas, W.; Berger, G.
1997-03-01
Single event effects are an important hazard to spacecraft and payloads. The advances in component technology, with shrinking dimensions and increasing complexity will give even more importance to single event effects in the future. The ground test facilities are complex and expensive and the complexities of installing a facility are compounded by the requirement that maximum control is to be exercised by users largely unfamiliar with accelerator technology. The PIF and the HIF are the result of experience gained in the field of single event effects testing and represent a unique collaboration between space technology and accelerator experts. Both facilities form an essential part of the European infrastructure supporting space projects. (J.P.N.)
Floating of Black Holes in Dimension of Information
Gholibeigian, Hassan; Gholibeigian, Ghasem; Gholibeigian, Kazem
2016-10-01
In our vision, there is dimension of information in addition of space-time's dimensions as the fifth dimension of the universe. All of the space-time, mater, and dark mater/energy are always floating in this dimension and whispering to its communication as well as black holes. Communication of information (CI) is done with each fundamental particle (string) from fifth dimension via its four animated sub-particles (sub-strings) for transferring a package of complete information of its quantum state in a Planck time. Fundamental particle after process of information by its sub-particles goes to its next stage while carries the stored processed information. CI as the ``fundamental symmetry'' leads all processes of the black holes as well as other phenomena. Every point of space-time needs on time to its new package, because duration of each processing is a Planck time. So, stored soft super-translation hairs in terms of soft gravitons or photons on black hole's horizon, or stored information on a holographic plate at the future boundary of the horizon [Hawking et al.] can be only accessible for particles which are in those positions (horizon and its boundary), not for other locations of black hole for their fast processing. AmirKabir University of Technology, Tehran, Iran.
Wormholes and black universes communicated with extra dimensions
International Nuclear Information System (INIS)
Bronnikov, K A; Korolyov, P A; Skvortsova, M V; Makhmudov, A
2017-01-01
In 6D general relativity with a phantom scalar field as a source of gravity, we present solutions that implement a transition from an effective 4D geometry times small extra dimensions to an effectively 6D space-time where the physical laws are different from ours. We consider manifolds with the structure M 0 ×M 1 ×M 2 , where M 0 is 2D Lorentzian space-time while each of M 1,2 can be a 2-sphere or a 2-torus. Some solutions describe wormholes with spherical symmetry in our space-time and toroidal extra dimensions. Others are of black universe type: at one end there is a 6D asymptotically anti-de Sitter black hole while beyond the horizon the geometry tends to a 4D de Sitter cosmology times a small 2D spherical extra space. (paper)
Deformed Spacetime Geometrizing Interactions in Four and Five Dimensions
Cardone, Fabio
2007-01-01
This volume provides a detailed discussion of the mathematical aspects and the physical applications of a new geometrical structure of space-time, based on a generalization ("deformation") of the usual Minkowski space, as supposed to be endowed with a metric whose coefficients depend on the energy. Such a formalism (Deformed Special Relativity, DSR) allows one to account for breakdown of local Lorentz invariance in the usual, special-relativistic meaning (however, Lorentz invariance is recovered in a generalized sense) to provide an effective geometrical description of the four fundamental interactions (electromagnetic, weak, strong and gravitational) Moreover, the four-dimensional energy-dependent space-time is just a manifestation of a larger, five-dimensional space in which energy plays the role of a fifth (non-compactified) dimension. This new five-dimensional scheme (Deformed Relativity in Five Dimensions, DR5) represents a true generalization of the usual Kaluza-Klein (KK) formalism. The mathematical pr...
Single Purpose Satellite Systems
Watkins, Warren
1989-01-01
This paper examines the need for tactically responsive space systems capable of supporting battlefield and fleet commanders. Terminology used to describe this category of satellite system varies according to organization or agency. The Defense Advanced Research Projects Agency's Lightsat, the Naval Space Command's SPINSAT, and the Air Force Space Command s TACSAT, are reviewed. The United State Space Command's space support mission IS addressed and the role single-purpose satellites can play ...
Asymptotic Charges at Null Infinity in Any Dimension
Campoleoni, Andrea; Francia, Dario; Heissenberg, Carlo
2018-03-01
We analyse the conservation laws associated with large gauge transformations of massless fields in Minkowski space. Our aim is to highlight the interplay between boundary conditions and finiteness of the asymptotically conserved charges in any space-time dimension, both even and odd, greater than or equal to three. After discussing non-linear Yang-Mills theory and revisiting linearised gravity, our investigation extends to cover the infrared behaviour of bosonic massless quanta of any spin.
Asymptotic Charges at Null Infinity in Any Dimension
Directory of Open Access Journals (Sweden)
Andrea Campoleoni
2018-03-01
Full Text Available We analyse the conservation laws associated with large gauge transformations of massless fields in Minkowski space. Our aim is to highlight the interplay between boundary conditions and finiteness of the asymptotically conserved charges in any space-time dimension, both even and odd, greater than or equal to three. After discussing nonlinear Yang–Mills theory and revisiting linearised gravity, our investigation extends to cover the infrared behaviour of bosonic massless quanta of any spin.
Distance Learning in Einstein’s Fourth Dimension
Directory of Open Access Journals (Sweden)
Robin Throne
2007-01-01
Full Text Available This article blends the concepts of space-time from theoretical physics and Einstein’s Relativity Theory to discuss the spatio-temporal nature of distance education. By comparing and contrasting speed-of-light space travel with the speed of computer processing, the leap is made to consider the fourth dimension and its phenomena for the Web traveler. Learning events are compared with events in time to depict the theory presented.
On twistors and conformal field theories from six dimensions
Energy Technology Data Exchange (ETDEWEB)
Saemann, Christian [Maxwell Institute for Mathematical Sciences, Department of Mathematics, Heriot-Watt University, Edinburgh EH14 4AS (United Kingdom); Wolf, Martin [Department of Mathematics, University of Surrey, Guildford GU2 7XH (United Kingdom)
2013-01-15
We discuss chiral zero-rest-mass field equations on six-dimensional space-time from a twistorial point of view. Specifically, we present a detailed cohomological analysis, develop both Penrose and Penrose-Ward transforms, and analyse the corresponding contour integral formulae. We also give twistor space action principles. We then dimensionally reduce the twistor space of six-dimensional space-time to obtain twistor formulations of various theories in lower dimensions. Besides well-known twistor spaces, we also find a novel twistor space amongst these reductions, which turns out to be suitable for a twistorial description of self-dual strings. For these reduced twistor spaces, we explain the Penrose and Penrose-Ward transforms as well as contour integral formulae.
Fractal dimension evolution and spatial replacement dynamics of urban growth
International Nuclear Information System (INIS)
Chen Yanguang
2012-01-01
Highlights: ► The fractal dimension growth can be modeled by Boltzmann’s equation. ► Boltzmann’s model suggests urban spatial replacement dynamics. ► If the rate of urban growth is too high, periodic oscillations or chaos will arise. ► Chaos is associated with fractals by the fractal dimension evolution model. ► The fractal dimension of urban form implies the space-filling ratio of a city. - Abstract: This paper presents a new perspective of looking at the relation between fractals and chaos by means of cities. Especially, a principle of space filling and spatial replacement is proposed to interpret the fractal dimension of urban form. The fractal dimension evolution of urban growth can be empirically modeled with Boltzmann’s equation. For the normalized data, Boltzmann’s equation is just equivalent to the logistic function. The logistic equation can be transformed into the well-known 1-dimensional logistic map, which is based on a 2-dimensional map suggesting spatial replacement dynamics of city development. The 2-dimensional recurrence relations can be employed to generate the nonlinear dynamical behaviors such as bifurcation and chaos. A discovery is thus made in this article that, for the fractal dimension growth following the logistic curve, the normalized dimension value is the ratio of space filling. If the rate of spatial replacement (urban growth) is too high, the periodic oscillations and chaos will arise. The spatial replacement dynamics can be extended to general replacement dynamics, and bifurcation and chaos mirror a process of complex replacement.
DEFF Research Database (Denmark)
Lykke-Olesen, Andreas
2006-01-01
This Ph.D. dissertation takes its offset in the migration of technology and computing power into our physical environment. The consequence of this movement, termed ubiquitous computing (Wieser, 1991), is a new relationship between humans, technology and spaces. In this new context, I seek...... to conceptualize space as more than the physical container for human activity. I do this by investigating space as interface. Based on a theory of space and place set forth by Tuan (Tuan, 1977), and informed by an explorative research approach, I make the distinction between space and place as a Euclidian space...... and a Phenomenological experienced place. In this perspective, place is created by humans as they appropriate space in investing it with emotions and memories and hereby making it meaningful. Space consists of formable physical and digital space, whereas place is made up by four dimensions relating to personal, physical...
Design of 5G Full Dimension Massive MIMO Systems
Nadeem, Qurrat-Ul-Ain
2017-10-13
This work discusses full-dimension multiple-inputmultiple- output (FD-MIMO) technology, which is currently an active area of research and standardization in wireless communications for evolution towards Fifth Generation (5G) cellular systems. FD-MIMO utilizes an active antenna system (AAS) with a two-dimensional (2D) planar array structure, that not only allows a large number of antenna elements to be packed within feasible base station form factors but also provides the ability of adaptive electronic beamforming in the threedimensional (3D) space. However, the compact structure of largescale planar arrays drastically increases the spatial correlation in FD-MIMO systems. In order to account for its effects, the generalized spatial correlation functions for channels constituted by individual elements and overall antenna ports in the AAS are derived. Exploiting the quasi-static channel covariance matrices of users, the problem of determining the optimal downtilt weight vector for antenna ports, which maximizes the minimum signalto- interference ratio of a multi-user multiple-input-single-output system, is formulated as a fractional optimization problem. A quasi-optimal solution is obtained through the application of semi-definite relaxation and Dinkelbach’s method. Finally, the user-group specific elevation beamforming scenario is devised, which offers significant performance gains as confirmed through simulations. These results have direct application in the analysis of 5G FD-MIMO systems.
The cosmological ‘constant’ and quantization in five dimensions
International Nuclear Information System (INIS)
Wesson, Paul S.
2011-01-01
Campbell's theorem ensures that all vacuum space-times in general relativity can be embedded in five dimensions, with the 4D scalar curvature expressed as an effective cosmological ‘constant’ Λ which depends on the extra coordinate. This Λ-landscape can be used to give insight to certain physical phenomena, such as the big bang and quantized particles.
Hausdorff dimension of the boundary of the immediate basin of ...
Indian Academy of Sciences (India)
The study of the Hausdorff dimension of the Julia sets of rational maps is one of the important topics in complex ... of the Julia sets of a family of rational maps when the subset is a quasicircle. 551. November ... Unlike the polynomials Pc(z) = zd + c, the parameter space of McMullen family has a special point at λ = 0.
Mass-imbalanced Three-Body Systems in Two Dimensions
DEFF Research Database (Denmark)
F. Bellotti, F.; Frederico, T.; T. Yamashita, M.
2013-01-01
We consider three-body systems in two dimensions with zero-range interactions for general masses and interaction strengths. The momentum-space Schr\\"odinger equation is solved numerically and in the Born-Oppenheimer (BO) approximation. The BO expression is derived using separable potentials and y...
The Structure of Integral Dimensions: Contrasting Topological and Cartesian Representations
Jones, Matt; Goldstone, Robert L.
2013-01-01
Diverse evidence shows that perceptually integral dimensions, such as those composing color, are represented holistically. However, the nature of these holistic representations is poorly understood. Extant theories, such as those founded on multidimensional scaling or general recognition theory, model integral stimulus spaces using a Cartesian…
Rank theorem in infinite dimension and lagrange multipliers
Blot, Joël
2018-01-01
We use an extension to the infinite dimension of the rank theorem of the differential calculus to establish a Karush-Huhn-Tucker theorem for optimization problems in Banach spaces. We provide an application to variational problems on bounded processus under equality constraints.
On the maximal dimension of a completely entangled subspace for ...
Indian Academy of Sciences (India)
R. Narasimhan (Krishtel eMaging) 1461 1996 Oct 15 13:05:22
K R PARTHASARATHY. Indian Statistical Institute, Delhi Centre, 7, S.J.S. Sansanwal Marg,. New Delhi 110 016, India. E-mail: krp@isid.ac.in. MS received 19 March 2004; revised 16 August 2004. Abstract. Let Hi be a finite dimensional complex Hilbert space of dimension di associated with a finite level quantum system Ai ...
Unified SU(4) color models in ten dimensions
International Nuclear Information System (INIS)
Hanlon, B.E.; Joshi, G.C.
1992-01-01
Some aspects of constructing unified models with SU(4) as the color group via a unifying group defined in ten dimensions are examined. Four dimensional theories are recovered using the Coset Space Dimensional Reduction scheme. Candidate models are considered in order to highlight some of the difficulties in constructing realistic four dimensional theories. 30 refs
Sphaleron rate at high temperature in 1+1 dimensions
International Nuclear Information System (INIS)
Smit, Jan; Tang, W.H.
1999-01-01
We resolve the controversy in the high temperature behavior of the sphaleron rate in the abelian Higgs model in 1+1 dimensions. The T 2 behavior at intermediate lattice spacings is found to change into T ((2)/(3)) behavior in the continuum limit. The results are supported by analytic arguments that the classical approximation is good for this model
A simpler and elegant algorithm for computing fractal dimension in ...
Indian Academy of Sciences (India)
A simpler and elegant algorithm for computing fractal dimension in higher dimensional state space. S GHORUI, A K DAS and N VENKATRAMANI. Laser and Plasma Technology Division, Power Plasma Devices Section, Bhabha Atomic Research. Centre, Mumbai 400 085, India. MS received 26 November 1999. Abstract.
Single-particle colloid tracking in four dimensions.
Anthony, Stephen M; Hong, Liang; Kim, Minsu; Granick, Steve
2006-11-21
Coating a close-packed fluorescent colloid monolayer with a nanometer-thick metal film followed by sonication in liquid produces modulated optical nanoprobes. The metal coating modulates the fluorescence as these structures rotate in suspension, enabling the use of these particles as probes to monitor both rotational and center-of-mass (translational) dynamics in complex environments. Here, we demonstrate methods to simultaneously measure two translational and two rotational degrees of freedom, with excellent agreement to theory. The capability to determine two angles of rotation opens several new avenues of future research.
Higuchi dimension of digital images.
Directory of Open Access Journals (Sweden)
Helmut Ahammer
Full Text Available There exist several methods for calculating the fractal dimension of objects represented as 2D digital images. For example, Box counting, Minkowski dilation or Fourier analysis can be employed. However, there appear to be some limitations. It is not possible to calculate only the fractal dimension of an irregular region of interest in an image or to perform the calculations in a particular direction along a line on an arbitrary angle through the image. The calculations must be made for the whole image. In this paper, a new method to overcome these limitations is proposed. 2D images are appropriately prepared in order to apply 1D signal analyses, originally developed to investigate nonlinear time series. The Higuchi dimension of these 1D signals is calculated using Higuchi's algorithm, and it is shown that both regions of interests and directional dependencies can be evaluated independently of the whole picture. A thorough validation of the proposed technique and a comparison of the new method to the Fourier dimension, a common two dimensional method for digital images, are given. The main result is that Higuchi's algorithm allows a direction dependent as well as direction independent analysis. Actual values for the fractal dimensions are reliable and an effective treatment of regions of interests is possible. Moreover, the proposed method is not restricted to Higuchi's algorithm, as any 1D method of analysis, can be applied.
Weakly infinite-dimensional spaces
International Nuclear Information System (INIS)
Fedorchuk, Vitalii V
2007-01-01
In this survey article two new classes of spaces are considered: m-C-spaces and w-m-C-spaces, m=2,3,...,∞. They are intermediate between the class of weakly infinite-dimensional spaces in the Alexandroff sense and the class of C-spaces. The classes of 2-C-spaces and w-2-C-spaces coincide with the class of weakly infinite-dimensional spaces, while the compact ∞-C-spaces are exactly the C-compact spaces of Haver. The main results of the theory of weakly infinite-dimensional spaces, including classification via transfinite Lebesgue dimensions and Luzin-Sierpinsky indices, extend to these new classes of spaces. Weak m-C-spaces are characterised by means of essential maps to Henderson's m-compacta. The existence of hereditarily m-strongly infinite-dimensional spaces is proved.
Emergence of four dimensional quantum mechanics from a deterministic theory in 11 dimensions
Doyen, G.; Drakova, D.
2015-07-01
We develop a deterministic theory which accounts for the coupling of a high dimensional continuum of environmental excitations (called gravonons) to massive particle in a very localized and very weak fashion. For the model presented Schrödinger's equation can be solved practically exactly in 11 spacetime dimensions and the result demonstrates that as a function of time an incoming matter wave incident on a screen extinguishes, except at a single interaction center on the detection screen. This transition is reminiscent of the wave - particle duality arising from the ’’collapse” (also called ’’process one”) postulated in the Copenhagen-von Neumann interpretation. In our theory it is replaced by a sticking process of the particle from the vacuum to the surface of the detection screen. This situation was verified in experiments by using massive molecules. In our theory this ”wave-particle transition” is connected to the different dimensionalities of the space for particle motion and the gravonon dynamics, the latter propagating in the hidden dimensions of 11 dimensional spacetime. The fact that the particle is detected at apparently statistically determined points on the screen is traced back to the weakness and locality of the interaction with the gravonons which allows coupling on the energy shell alone. Although the theory exhibits a completely deterministic ”chooser” mechanism for single site sticking, an apparent statistical character results, as it is found in the experiments, due to small heterogeneities in the atomic and gravonon structures.
Random sequential addition of hard spheres in high Euclidean dimensions
Torquato, S.; Uche, O. U.; Stillinger, F. H.
2006-12-01
Sphere packings in high dimensions have been the subject of recent theoretical interest. Employing numerical and theoretical methods, we investigate the structural characteristics of random sequential addition (RSA) of congruent spheres in d -dimensional Euclidean space Rd in the infinite-time or saturation limit for the first six space dimensions (1≤d≤6) . Specifically, we determine the saturation density, pair correlation function, cumulative coordination number and the structure factor in each of these dimensions. We find that for 2≤d≤6 , the saturation density ϕs scales with dimension as ϕs=c1/2d+c2d/2d , where c1=0.202048 and c2=0.973872 . We also show analytically that the same density scaling is expected to persist in the high-dimensional limit, albeit with different coefficients. A byproduct of this high-dimensional analysis is a relatively sharp lower bound on the saturation density for any d given by ϕs≥(d+2)(1-S0)/2d+1 , where S0ɛ[0,1] is the structure factor at k=0 (i.e., infinite-wavelength number variance) in the high-dimensional limit. We demonstrate that a Palàsti-type conjecture (the saturation density in Rd is equal to that of the one-dimensional problem raised to the d th power) cannot be true for RSA hyperspheres. We show that the structure factor S(k) must be analytic at k=0 and that RSA packings for 1≤d≤6 are nearly “hyperuniform.” Consistent with the recent “decorrelation principle,” we find that pair correlations markedly diminish as the space dimension increases up to six. We also obtain kissing (contact) number statistics for saturated RSA configurations on the surface of a d -dimensional sphere for dimensions 2≤d≤5 and compare to the maximal kissing numbers in these dimensions. We determine the structure factor exactly for the related “ghost” RSA packing in Rd and demonstrate that its distance from “hyperuniformity” increases as the space dimension increases, approaching a constant asymptotic value
The Existential Dimension of Right
DEFF Research Database (Denmark)
Hartz, Emily
2017-01-01
The following article paves out the theoretical ground for a phenomenological discussion of the existential dimension of right. This refers to a dimension of right that is not captured in standard treatments of right, namely the question of whether – or how the concept of rights relates...... for discussing the existential dimension of right by bringing central parts of Fichte’s and Arendt’s work into dialogue. By facilitating this – admittedly unusual – dialogue between Fichte and Arendt the author explicates how, for both Fichte and Arendt, the concept of right can only be adequately understood...... as referring to the existential condition of plurality and uses this insight to draw up a theoretical ground for further phenomenological analysis of right....
Correlated Electrons in Reduced Dimensions
Energy Technology Data Exchange (ETDEWEB)
Bonesteel, Nicholas E [Florida State Univ., Tallahassee, FL (United States)
2015-01-31
This report summarizes the work accomplished under the support of US DOE grant # DE-FG02-97ER45639, "Correlated Electrons in Reduced Dimensions." The underlying hypothesis of the research supported by this grant has been that studying the unique behavior of correlated electrons in reduced dimensions can lead to new ways of understanding how matter can order and how it can potentially be used. The systems under study have included i) fractional quantum Hall matter, which is realized when electrons are confined to two-dimensions and placed in a strong magnetic field at low temperature, ii) one-dimensional chains of spins and exotic quasiparticle excitations of topologically ordered matter, and iii) electrons confined in effectively ``zero-dimensional" semiconductor quantum dots.
The Creative Dimension of Visuality
DEFF Research Database (Denmark)
Michelsen, Anders Ib
2013-01-01
analysis relying on language/linguistics as a model for explaining culture? More specifically, how can the – creative – novelty of visual culture be addressed by a notion of discourse? This essay will argue that the debate on visual culture is lacking with regard to discerning the creative dimension of its...... own appearance. It will indicate an alternative conceptual framework based on Johann P. Arnason’s draft of tripartite culturalization which focuses on a shift from essences to dimensions of culture. This will be further developed by relating Maurice Merleau-Ponty’s idea of ‘chiasm’ of ‘the visible...
The Ethical Dimension of Innovation
DEFF Research Database (Denmark)
Nogueira, Leticia Antunes; Nogueira, Tadeu Fernando
2014-01-01
The view of innovation as a positive concept has been deeply rooted in business and academic cultures ever since Schumpeter coined the concept of creative destruction. Even though there is a large body of literature on innovation studies, limited attention has been given to its ethical dimension....... In this chapter, the ethical implications of innovations are illustrated with a case study of “destructive creation” in the food industry, and upon which an argumentative analysis is conducted. The main message of this chapter is that innovations have inherent ethical dimensions and that quality innovations...
46 CFR 108.205 - Wash spaces; toilet spaces; and shower spaces.
2010-10-01
... 46 Shipping 4 2010-10-01 2010-10-01 false Wash spaces; toilet spaces; and shower spaces. 108.205...; toilet spaces; and shower spaces. (a) For the purposes of this section— (1) “Private facility” means a toilet, washing, or shower space that is accessible only from one single or double occupancy sleeping...
Cadaveric assessment of kidney dimensions among Nigerians- a ...
African Journals Online (AJOL)
The usually paired human kidneys are retroperitoneal urinary organs with some endocrine functions. Standard text books of anatomy ascribe single value to each of the dimension of length, width and thickness. These values do not give consideration to racial and genetic variability in human morphology. They may thus be ...
Signals of universal extra dimension at the international linear collider
Indian Academy of Sciences (India)
Abstract. In the minimal universal extra dimension model, single production of = 2 gauge bosons provides a unique discriminating feature from supersymmetry. We discuss how the proposed international linear collider can act as a = 2 factory, much in the same vein as LEP.
Examining the Underlying Dimensions of Morphological Awareness and Vocabulary Knowledge
Spencer, Mercedes; Muse, Andrea; Wagner, Richard K.; Foorman, Barbara; Petscher, Yaacov; Schatschneider, Christopher; Tighe, Elizabeth L.; Bishop, M. Denise
2015-01-01
We report results from two studies on the underlying dimensions of morphological awareness and vocabulary knowledge in elementary-aged children. In Study 1, 99 fourth-grade students were given multiple measures of morphological awareness and vocabulary. A single factor accounted for individual differences in all morphology and vocabulary…
DEFF Research Database (Denmark)
Lykke-Olesen, Andreas
2006-01-01
to conceptualize space as more than the physical container for human activity. I do this by investigating space as interface. Based on a theory of space and place set forth by Tuan (Tuan, 1977), and informed by an explorative research approach, I make the distinction between space and place as a Euclidian space...... with actual use (Hallnäs et al. 2006). The challenge thus becomes understanding space as the interface, and further how intentions can be induced into the design of space in ways that point towards the dimensions of place, when interpreted in actual use situations. By designing and exploring a range......This Ph.D. dissertation takes its offset in the migration of technology and computing power into our physical environment. The consequence of this movement, termed ubiquitous computing (Wieser, 1991), is a new relationship between humans, technology and spaces. In this new context, I seek...
Dimensional Reduction over Fuzzy Coset Spaces
Aschieri, P; Manousselis, P; Madore, J
2004-01-01
We examine gauge theories on Minkowski space-time times fuzzy coset spaces. This means that the extra space dimensions instead of being a continuous coset space S/R are a corresponding finite matrix approximation. The gauge theory defined on this non-commutative setup is reduced to four dimensions and the rules of the corresponding dimensional reduction are established. We investigate in particular the case of the fuzzy sphere including the dimensional reduction of fermion fields.
Dimensional Reduction over Fuzzy Coset Spaces
Aschieri, P.; Madore, J.; Manousselis, P.; Zoupanos, G.
2004-04-01
We examine gauge theories on Minkowski space-time times fuzzy coset spaces. This means that the extra space dimensions instead of being a continuous coset space S/R are a corresponding finite matrix approximation. The gauge theory defined on this non-commutative setup is reduced to four dimensions and the rules of the corresponding dimensional reduction are established. We investigate in particular the case of the fuzzy sphere including the dimensional reduction of fermion fields.
Kellett, B. J.; Griffin, D. K.; Bingham, R.; Campbell, R. N.; Forbes, A.; Michaelis, M. M.
2008-05-01
Hybrid space propulsion has been a feature of most space missions. Only the very early rocket propulsion experiments like the V2, employed a single form of propulsion. By the late fifties multi-staging was routine and the Space Shuttle employs three different kinds of fuel and rocket engines. During the development of chemical rockets, other forms of propulsion were being slowly tested, both theoretically and, relatively slowly, in practice. Rail and gas guns, ion engines, "slingshot" gravity assist, nuclear and solar power, tethers, solar sails have all seen some real applications. Yet the earliest type of non-chemical space propulsion to be thought of has never been attempted in space: laser and photon propulsion. The ideas of Eugen Saenger, Georgii Marx, Arthur Kantrowitz, Leik Myrabo, Claude Phipps and Robert Forward remain Earth-bound. In this paper we summarize the various forms of nonchemical propulsion and their results. We point out that missions beyond Saturn would benefit from a change of attitude to laser-propulsion as well as consideration of hybrid "polypropulsion" - which is to say using all the rocket "tools" available rather than possibly not the most appropriate. We conclude with three practical examples, two for the next decades and one for the next century; disposal of nuclear waste in space; a grand tour of the Jovian and Saturnian moons - with Huygens or Lunoxod type, landers; and eventually mankind's greatest space dream: robotic exploration of neighbouring planetary systems.
Reddell, Brandon; Bailey, Chuck; Nguyen, Kyson; O'Neill, Patrick; Gaza, Razvan; Patel, Chirag; Cooper, Jaime; Kalb, Theodore
2017-01-01
We present the results of SEE testing with high energy protons and with low and high energy heavy ions. This paper summarizes test results for components considered for Low Earth Orbit and Deep Space applications.
2015-04-01
This document describes the objectives, methods, analyses, and results of a study used to quantify the effects of future space operations : on the National Airspace System (NAS), and to demonstrate the possible benefits of one proposed strategy to mi...
String theory in four dimensions
1988-01-01
``String Theory in Four Dimensions'' contains a representative collection of papers dealing with various aspects of string phenomenology, including compactifications on smooth manifolds and more general conformal field theories. Together with the lucid introduction by M. Dine, this material gives the reader a good working knowledge of our present ideas for connecting string theory to nature.
Serre dimension of monoid algebras
Indian Academy of Sciences (India)
MANOJ K KESHARI
Department of Mathematics, Indian Institute of Technology Bombay,. Powai, Mumbai 400 076, India. *Corresponding author. E-mail: keshari@math.iitb.ac.in; mathparvez@gmail.com. MS received 7 July 2015; revised 20 October 2015. Abstract. Let R be a commutative Noetherian ring of dimension d, M a commutative.
Collective dimensions in animal ethics
Bovenkerk, B.; Verweij, M.F.
2015-01-01
Due to its emphasis on experiential interests, animal ethics tends to focus on individuals as the sole unit of moral concern. Many issues in animal ethics can be fruitfully analysed in terms of obligations towards individual animals, but some problems require reflection about collective dimensions
Correlation Dimension Estimation for Classification
Czech Academy of Sciences Publication Activity Database
Jiřina, Marcel; Jiřina jr., M.
2006-01-01
Roč. 1, č. 3 (2006), s. 547-557 ISSN 1895-8648 R&D Projects: GA MŠk(CZ) 1M0567 Institutional research plan: CEZ:AV0Z10300504 Keywords : correlation dimension * probability density estimation * classification * UCI MLR Subject RIV: BA - General Mathematics
Teachers' Careers: The Objective Dimension.
Evetts, Julia
1986-01-01
Analyzes the objective dimension of teachers' careers showing how 530 British male/female teachers are distributed throughout the pay scale and promotions making up the formal structure of teaching. Indicates length of experience is the rewarding but not the sole factor in bureaucratic structure and differential male/female career achievements.…
Physics with large extra dimensions
Indian Academy of Sciences (India)
The recent understanding of string theory opens the possibility that the string scale can be as low as a few TeV. The apparent weakness of gravitational interactions can then be accounted by the existence of large internal dimensions, in the sub-millimeter region. Furthermore, our world must be confined to live on a brane ...
Quantum Gravity in Two Dimensions
DEFF Research Database (Denmark)
Ipsen, Asger Cronberg
The topic of this thesis is quantum gravity in 1 + 1 dimensions. We will focus on two formalisms, namely Causal Dynamical Triangulations (CDT) and Dy- namical Triangulations (DT). Both theories regularize the gravity path integral as a sum over triangulations. The difference lies in the class...
Dimension Reduction Regression in R
Directory of Open Access Journals (Sweden)
Sanford Weisberg
2002-01-01
Full Text Available Regression is the study of the dependence of a response variable y on a collection predictors p collected in x. In dimension reduction regression, we seek to find a few linear combinations β1x,...,βdx, such that all the information about the regression is contained in these linear combinations. If d is very small, perhaps one or two, then the regression problem can be summarized using simple graphics; for example, for d=1, the plot of y versus β1x contains all the regression information. When d=2, a 3D plot contains all the information. Several methods for estimating d and relevant functions of β1,..., βdhave been suggested in the literature. In this paper, we describe an R package for three important dimension reduction methods: sliced inverse regression or sir, sliced average variance estimates, or save, and principal Hessian directions, or phd. The package is very general and flexible, and can be easily extended to include other methods of dimension reduction. It includes tests and estimates of the dimension , estimates of the relevant information including β1,..., βd, and some useful graphical summaries as well.
The Subjective Dimension of Nazism
Föllmer, M.
2013-01-01
The present historiographical review discusses the subjective dimension of Nazism, an ideology and regime that needed translation into self-definitions, gender roles, and bodily practices to implant itself in German society and mobilize it for racial war. These studies include biographies of some of
Massive Gravity in Three Dimensions
Bergshoeff, Eric A.; Hohm, Olaf; Townsend, Paul K.
2009-01-01
A particular higher-derivative extension of the Einstein-Hilbert action in three spacetime dimensions is shown to be equivalent at the linearized level to the (unitary) Pauli-Fierz action for a massive spin-2 field. A more general model, which also includes "topologically-massive" gravity as a
Physics with large extra dimensions
Indian Academy of Sciences (India)
Early motivation for large extra dimensions. Attempts to construct a consistent theory for ... of perturbative (heterotic) string theory that leads to the spectacular prediction of the possible existence of extra ... perturbation theory, leading to different powers of the string coupling gS in the corresponding effective action: SÁ = ∫.
Dimensions of problem based learning
DEFF Research Database (Denmark)
Nielsen, Jørgen Lerche; Andreasen, Lars Birch
2013-01-01
The article contributes to the literature on problem based learning and problem-oriented project work, building on and reflecting the experiences of the authors through decades of work with problem-oriented project pedagogy. The article explores different dimensions of problem based learning such...
Effective dimension in flocking mechanisms
International Nuclear Information System (INIS)
Baglietto, Gabriel; Albano, Ezequiel V.
2011-01-01
Even in its minimal representation (Vicsek Model, VM [T. Vicsek, A. Czirok, E. Ben-Jacob, I. Cohen and O. Shochet. Phys. Rev. Lett. 75, 1226 (1995).]), the widespread phenomenon of flocking raises intriguing questions to the statistical physicists. While the VM is very close to the better understood XY Model because they share many symmetry properties, a major difference arises by the fact that the former can sustain long-range order in two dimensions, while the latter can not. Aiming to contribute to the understanding of this feature, by means of extensive numerical simulations of the VM, we study the network structure of clusters showing that they can also sustain purely orientational, mean-field-like, long-range order. We identify the reason of this capability with the key concept of ''effective dimension.'' In fact, by analyzing the behavior of the average path length and the mean degree, we show that this dimension is very close to four, which coincides with the upper critical dimension of the XY Model, where orientational order is also of a mean-field nature. We expect that this methodology could be generalized to other types of dynamical systems.
The Visuospatial Dimension of Writing
Olive, Thierry; Passerault, Jean-Michel
2012-01-01
The authors suggest that writing should be conceived of not only as a verbal activity but also as a visuospatial activity, in which writers process and construct visuospatial mental representations. After briefly describing research on visuospatial cognition, they look at how cognitive researchers have investigated the visuospatial dimension of…
Interpretation and the Aesthetic Dimension
Mortensen, Charles O.
1976-01-01
The author, utilizing a synthesis of philosophic comments on aesthetics, provides a discourse on the aesthetic dimension and offers examples of how interpreters can nurture the innate sense of beauty in man. Poetic forms, such as haiku, are used to relate the aesthetic relationship between man and the environment. (BT)
Correlation Dimension-Based Classifier
Czech Academy of Sciences Publication Activity Database
Jiřina, Marcel; Jiřina jr., M.
2014-01-01
Roč. 44, č. 12 (2014), s. 2253-2263 ISSN 2168-2267 R&D Projects: GA MŠk(CZ) LG12020 Institutional support: RVO:67985807 Keywords : classifier * multidimensional data * correlation dimension * scaling exponent * polynomial expansion Subject RIV: BB - Applied Statistics, Operational Research Impact factor: 3.469, year: 2014
The structure of visual spaces
Koenderink, J.J.; van Doorn, A.J.
2008-01-01
The “visual space” of an optical observer situated at a single, fixed viewpoint is necessarily very ambiguous. Although the structure of the “visual field” (the lateral dimensions, i.e., the “image”) is well defined, the “depth” dimension has to be inferred from the image on the basis of “monocular
A Dimension Space for Evaluating Collaborative Musical Performance Systems
Hattwick, Ian; Wanderley, Marcelo
2012-01-01
The configurability and networking abilities of digital musical instruments increases the possibilities for collaboration in musical performances. Computer music ensembles such as laptop orchestras are becoming increasingly common and provide laboratories for the exploration of these possibilities. However, much of the literature regarding the creation of DMIs has been focused on individual expressivity, and their potential for collaborative performance has been under-utilized. This paper mak...
Non-relativistic supergravity in three space-time dimensions
Zojer, Thomas
2016-01-01
This year Einstein's theory of general relativity celebrates its one hundredth birthday. It supersedes the non-relativistic Newtonian theory of gravity in two aspects: i) there is a limiting velocity, nothing can move quicker than the speed of light and ii) the theory is valid in arbitrary
Ideological Dimension of Party Political Space of Modern Turkey
Directory of Open Access Journals (Sweden)
Galkina Elena Vyacheslavovna
2015-12-01
Full Text Available The article is devoted to ideological issues in the Turkish party system in the context of the electoral process. The authors analyze the internal content and principles of ideological platforms of the leading parties in Turkey. The formal analysis of party programs allowed to determine the value of the ideology for the functioning of the parties. Besides, analysis of the results of opinion polls conducted by the Turkish public opinion research centers revealed the functionality of ideology in the context of election campaigns. The object of the study was the ideologies of 4 major political parties of Turkey, which entered National Parliament after elections in November 2015. These are conservative Justice and Development Party, the center-left Republican People’s Party, the National Movement Party, the Democratic Party of peoples. Analysis of party programs and other official documents showed that all four parties clearly define their ideological identity and political position. However, despite the clarity of such ideological identification, analysis of the last two election campaigns in Turkey revealed a trend among major parties to refuse from the traditional ideological rhetoric and to practice populist methods of voters attracting. The paper discloses the contents of the political stratification of Turkish society, depending on the ideological preferences of representatives of various social groups. Causative factors of ideological discourse rise are considered in the context of inter-party competition of leading political forces of the Turkish Republic. A comparative analysis shows that the Republican People’s Party and the Nationalist Movement Party are both doctrinal with distinct ideological postulates that have a national base. In contrast, the Justice and Development Party, as well as the People’s Democratic Party are more pragmatic and charismatic at the same time.
Diffusion-limited reaction in one dimension
Lythe, Grant
2006-10-01
Reaction rates that are controlled by collisions between diffusing particles depend on the distribution of distances between particles as well as on the concentration of particles. Classical treatment of reaction rates thus produces a hierarchy of particle correlation functions. However, when collision between particles results in annihilation, it is possible to sidestep this hierarchy and find an exact solution for the mean number of particles per unit length as a function of time. This article is concerned with the case, in one space dimension, where new particles are born or “nucleated”, two at a time, at random times and positions, with a fixed distance b between the particles at birth. We review an exact method for calculating the mean lifetime of a particle and an exact rate equation in terms of the correlation function. In addition, the distribution of particle lifetimes is calculated under a “constant-killing-rate” approximation that compares favourably with the results of numerical experiments.
Interacting fermions in one spatial dimensions
International Nuclear Information System (INIS)
Wolf, D.
1982-01-01
This thesis contains in its first part a critical survey about the method of the bosonization of fermi fields in one spatial dimension and its application to the Luttinger and the massive Thirring model. The first chapter served for the explanation of the term of the unitary inequivalence. Thereby two generally valid facts could be demonstrated very illustratively by the example of a fermion algebra and its representations, namely first that infinite, direct product space are not separable, and second that weak equivalence of the vacua is equivalent to the unitary equivalence of the corresponding representations of the field algebra. In the second part the statement first studied by Luther (1976) and since then often cited, that the continuum limit of the Heisenberg model is the massive Thirring model. It is concluded that it can up to today not be considered as proved although indications for its validity can be found. (orig./HSI) [de
Higgs Phenomenology of Minimal Universal Extra Dimensions
Directory of Open Access Journals (Sweden)
Kakizaki Mitsuru
2012-06-01
Full Text Available The minimal model of Universal Extra Dimensions (MUED is briefly reviewed. We explain how the cross-sections for Higgs production via gluon fusion and decay into photons are modified, relative the the Standard Model (SM values, by KK particles running in loops, leading to an enhancement of the gg → h → γγ and gg → h → W+W− cross-sections. ATLAS and CMS searches for the SM Higgs in these channels are reinterpreted in the context of MUED and used to place new limits on the MUED parameter space. Only a small region of between 1 and 3 GeV around mh = 125 GeV for 500 GeV < R−1 < 1600 GeV remains open at the 95 % confidence level.
Exact spectrum of anomalous dimensions of planar N = 4 supersymmetric Yang-Mills theory.
Gromov, Nikolay; Kazakov, Vladimir; Vieira, Pedro
2009-09-25
We present a set of functional equations defining the anomalous dimensions of arbitrary local single trace operators in planar N = 4 supersymmetric Yang-Mills theory. It takes the form of a Y system based on the integrability of the dual superstring sigma model on the five-dimensional anti-de Sitter space (AdS_{5} x S;{5}) background. This Y system passes some very important tests: it incorporates the full asymptotic Bethe ansatz at large length of operator L, including the dressing factor, and it confirms all recently found wrapping corrections. The recently proposed AdS_{4}/three-dimensional conformal field theory duality is also treated in a similar fashion.
Interpretation of flow dimensions from constant pressure injection test
International Nuclear Information System (INIS)
Kuusela-Lahtinen, A.; Poteri, A.
2010-06-01
This report deals with interpretation methods of single-hole hydraulic tests. A special emphasis is on new analysis methods of a single-hole hydraulic test, called a constant pressure injection test. This hydraulic test type is used in Posiva's site investigation at Olkiluoto. Single-hole hydraulic tests are examined in order to find out methods to analyse channelling of the flow that is related to transport properties along the flow paths. The flow dimensions inferred from the constant pressure tests are considered to indicate the channelling of the flow in the scale of a single fracture or in the fracture network. One can use semi-log derivates of measurement data plotted in log-log diagrams for the interpretation of flow dimension. After that the appropriate flow solution can be chosen to infer the values of conductivity and specific storage. Channelling is studied from Posiva's data by analysing the transient injection period of a constant pressure injection test. Software called AQTESOLV is used in a new procedure, which is illustrated by studying two examples. Both examples are based on single hole hydraulic tests that are performed in the borehole OLKR10 using a 2 m test interval approximately at the depth of the planned repository of the nuclear waste (depth of about 400 - 450 m). One of the test intervals is intersected by a filled fracture and the analysed flow dimensions also indicates flow in a fractures, with inferred flow dimensions of n = 1.5 or n = 2. The flow dimension n = 1.5 represents a possibility of narrowing flowpaths. The other analysed test interval is intersected by three filled fractures. In this case, analysis of the flow dimension show behaviour that is related to a fracture network (homogeneous porous media), with interpreted flow dimensions of n = 2.5 - 3. This report also shows results for simulation of a constant pressure test in an artificial heterogeneous fracture. Flow dimension is analysed by performing simulated pumping tests
Magnetic and low-dissipation applications of WTe2 at limited dimensions
National Aeronautics and Space Administration — My research on WTe2 at limited dimensions seeks to lay the groundwork for the next generation of magnetic sensors and low-dissipation circuitry. These applications...
Lucky Basuki, Holiman Chandra Yusita Kusumarini
2013-01-01
Lifestyle of modern people use some time to move out of residence (public space) makes the most of the private activities can not be fulfilled. It is an idea and the idea of creating a space that can meet the needs of the private in public spaces with small dimensions. Private space in the design of the library is housed in Petra Christian University Surabaya as space scope of small private space (minimal private space dimension). The creation of small private space in the interior of the lib...
Directory of Open Access Journals (Sweden)
Anthea G. Blunden
2015-01-01
Full Text Available A variety of converging operations demonstrate key differences between separable dimensions, which can be analyzed independently, and integral dimensions, which are processed in a non-analytic fashion. A recent investigation of response time distributions, applying a set of logical rule-based models, demonstrated that integral dimensions are pooled into a single coactive processing channel, in contrast to separable dimensions, which are processed in multiple, independent processing channels. This paper examines the claim that arbitrary dimensions created by factorially morphing four faces are processed in an integral manner (i.e., coactively. In two experiments, sixteen participants completed a categorization task in which either upright or inverted morph stimuli were classified in a speeded fashion. Analyses focused on contrasting different assumptions about the psychological representation of the stimuli, perceptual and decisional separability, and the processing architecture. We report consistent individual differences which demonstrate a mixture of some observers who demonstrate coactive processing with other observers who process the dimensions in a parallel self-terminating manner.
Applying EFT to Higgs pair production in universal extra dimensions
Energy Technology Data Exchange (ETDEWEB)
Edelhäuser, Lisa; Knochel, Alexander; Steeger, Thomas [Institut für Theoretische Teilchenphysik und Kosmologie, RWTH Aachen, Sommerfeldstr. 16, Aachen, 52074 (Germany)
2015-11-09
We investigate single Higgs and Higgs pair production at the LHC in models of Universal Extra Dimensions. After calculating the relevant cross sections, we use the UED model as a testing ground for the Effective Field Theory approach to physics beyond the Standard Model. We show how the UED contributions to Higgs production can be matched to a dimension-6 operator. We then discuss the range of validity of this approach, in particular for Higgs pair production, and determine the sensitivity to the number of KK modes in the loop.
DEFF Research Database (Denmark)
Johannessen, Runa
The thesis is concerned with spatial practices of resistance employed in Palestinian struggles against Israel’s violent dispossession of Palestinian land through half a century of occupation. In the political configuration of the built space of the West Bank, architecture appears as a tactically...... deployed weapon of territorial control and a dialectical resistance to displacement. Standing in the position of being both a means to achieve an objective and the objective in itself, the elementary gestures of architecture —to control and inhabit a place —are employed in a conflict that concerns......, fundamentally, who has the right to a future in this land. By viewing architecture in its dual dimension of praxis and object, built structures are investigated as agents that induce and manifest territorial struggles. The spatial instrumentalisation of architecture is effected by Israel through commonplace...
Gravitational instability in higher dimensions
Gibbons, Gary; Hartnoll, Sean A.
2002-09-01
We explore a classical instability of spacetimes of dimension D>4. First, we consider static solutions: generalized black holes and brane world metrics. The dangerous mode is a tensor mode on an Einstein base manifold of dimension D-2. A criterion for instability is found for the generalized Schwarzschild, AdS-Schwarzschild and topological black hole spacetimes in terms of the Lichnerowicz spectrum on the base manifold. Secondly, we consider perturbations in time-dependent solutions: Generalized dS and AdS. Thirdly we show that, subject to the usual limitations of a linear analysis, any Ricci flat spacetime may be stabilized by embedding into a higher dimensional spacetime with cosmological constant. We apply our results to pure AdS black strings. Finally, we study the stability of higher dimensional ``bubbles of nothing.''
Flavour physics from extra dimensions
Martinelli, G; Scrucca, C A; Silvestrini, L
2004-01-01
We discuss the possibility of introducing an SU(2) global flavour symmetry in the context of flat extra dimensions. In particular we concentrate on the 5-dimensional case and we study how to obtain the flavour structure of the Standard Model quark sector compacti(ying the fifth dimension on the orbifold St/Z2 a la Scberk-Scbwarz (SS). We show that in this case it is possible to justify the five orders of magnitude among the values of the quark masses with only one parameter: the SS flavour parameter. The non-local nature of the SS symmetry breaking mechanism allows to realize this without introducing new instabilities in the theory.
INTERDEPENDENCE BETWEEN RELATIONSHIP QUALITY DIMENSIONS
Directory of Open Access Journals (Sweden)
Mario Pepur
2011-02-01
Full Text Available Tourism-dependent economy, unfavourable structure of accommodation and hotel capacity, seasonality of business and liquidity problems indicate importance of the relationships between hotels and banks in Croatia. Since the capital investments in new and modern capacities are necessity, the quality of their relationship would determine the future of Croatian economy as a whole in the long run. Regarding the capital investments, it is crucially important that cooperation between the employees in both business entities is based on the satisfaction, trust and commitment. In this way, every potential uncertainty as a consequence of the entity’s actions could be minimized. In this paper, 356 tourist objects are hierarchically clustered according to the relationship quality dimensions for the purpose of testing the characteristics according to which the clusters significantly differentiate. Consequently, the interdependence between the observed relationship quality dimensions is examined.
The social dimension of entrepreneurship
DEFF Research Database (Denmark)
Ulhøi, John Parm
2005-01-01
This paper proposes an integrative framework to conceptualize important social dimensions of entrepreneurship. The paper reviews and evaluates the current status of research dealing with entrepreneurship, social capital and trust. The proposed framework rests on the recognition that entrepreneuri...... activities are results of social interactions and mechanisms. In consequence, entrepreneurship cannot merely be understood in terms of 'personality characteristics' or in sterile economic terms. The paper addresses by concluding implications for practitioners and for research.......This paper proposes an integrative framework to conceptualize important social dimensions of entrepreneurship. The paper reviews and evaluates the current status of research dealing with entrepreneurship, social capital and trust. The proposed framework rests on the recognition that entrepreneurial...
Approximation by Chebyshevian Bernstein Operators versus Convergence of Dimension Elevation
Ait-Haddou, Rachid
2016-03-18
On a closed bounded interval, consider a nested sequence of Extended Chebyshev spaces possessing Bernstein bases. This situation automatically generates an infinite dimension elevation algorithm transforming control polygons of any given level into control polygons of the next level. The convergence of these infinite sequences of polygons towards the corresponding curves is a classical issue in computer-aided geometric design. Moreover, according to recent work proving the existence of Bernstein-type operators in such Extended Chebyshev spaces, this nested sequence is automatically associated with an infinite sequence of Bernstein operators which all reproduce the same two-dimensional space. Whether or not this sequence of operators converges towards the identity on the space of all continuous functions is a natural issue in approximation theory. In the present article, we prove that the two issues are actually equivalent. Not only is this result interesting on the theoretical side, but it also has practical implications. For instance, it provides us with a Korovkin-type theorem of convergence of any infinite dimension elevation algorithm. It also enables us to tackle the question of convergence of the dimension elevation algorithm for any nested sequence obtained by repeated integration of the kernel of a given linear differential operator with constant coefficients. © 2016 Springer Science+Business Media New York
The social dimensions of entrepreneurship
DEFF Research Database (Denmark)
Ulhøi, John Parm
2005-01-01
activities are results of social interactions and mechanisms. In consequence, entrepreneurship cannot merely be understood in terms of "personality characteristics" or in sterile economic terms. In closing, the paper addresses implications for practitioners and for research. Udgivelsesdato: AUG......This paper proposes an integrative framework to conceptualize important social dimensions of entrepreneurship. The paper reviews and evaluates the current status of research dealing with entrepreneurship, social capital and trust. The proposed framework rests on the recognition that entrepreneurial...
String theory in four dimensions
International Nuclear Information System (INIS)
Dine, M.
1988-01-01
A representative sample of current ideas about how one might develop a string phenomenology is presented. Some of the obstacles which lie in between string theory and contact with experiment are described. It is hoped that this volume will provide the reader with ways of thinking about string theory in four dimensions and provide tools for asking questions about string theory and ordinary physics. 102 refs
Apathy dimensions in Parkinson's disease
Radakovic, Ratko; Davenport, Richard; Starr, John M; Abrahams, Sharon
2018-01-01
OBJECTIVE: Apathy is a prominent and disabling symptom in Parkinson's disease (PD) and is a multidimensional behaviour, but which dimensions are specifically affected is unclear. Therefore, the aim of this preliminary study was to determine the psychometric properties of the Dimensional Apathy Scale (DAS) and explore the multidimensional profile of apathy in PD patients. METHODS: Thirty-four PD patients, with 30 of their informants/carers, and 34 healthy controls, with 30 of their informants,...
Apathy dimensions in Parkinson's disease.
Radakovic, Ratko; Davenport, Richard; Starr, John M; Abrahams, Sharon
2018-01-01
Apathy is a prominent and disabling symptom in Parkinson's disease (PD) and is a multidimensional behaviour, but which dimensions are specifically affected is unclear. Therefore, the aim of this preliminary study was to determine the psychometric properties of the Dimensional Apathy Scale (DAS) and explore the multidimensional profile of apathy in PD patients. Thirty-four PD patients, with 30 of their informants/carers, and 34 healthy controls, with 30 of their informants, completed the DAS, Apathy Evaluation Scale and the Geriatric Depression Scale Short Form. Motor staging and independent living status were recorded. Comparative group analyses revealed that PD patients were significantly more apathetic on self-rated executive (p = 0.01) and initiation (p = 0.03) dimensions than controls, where only executive apathy was significantly higher in ratings of patients' informants/carers compared with controls' informants (p = 0.02). A third of patients were impaired on at least one apathy dimension. Additionally, patients with apathy tended to have more impaired activities of daily living, while none of the apathy dimensions related to motor disability. Our findings show the DAS is a valid and reliable multidimensional apathy tool for use in PD. PD is characterised by an executive apathy profile as determined by informants/carers, although patients described both executive and initiation apathy. This indicates a lack of motivation for planning, organisation and attention and lack of initiation of thoughts or behaviours. Further research is needed to determine the cognitive underpinnings of this emerging apathy profile and the clinical impact in PD. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.
Dimension Reduction Techniques in Morhpometrics
Kratochvíl, Jakub
2011-01-01
This thesis centers around dimensionality reduction and its usage on landmark-type data which are often used in anthropology and morphometrics. In particular we focus on non-linear dimensionality reduction methods - locally linear embedding and multidimensional scaling. We introduce a new approach to dimensionality reduction called multipass dimensionality reduction and show that improves the quality of classification as well as requiring less dimensions for successful classification than the...
Serre dimension of monoid algebras
Indian Academy of Sciences (India)
Let R be a commutative Noetherian ring of dimension d , M a commutative cancellative torsion-free monoid of rank r and P a finitely generated projective R [ M ] -module of rank t . Assume M is Φ -simplicial seminormal. If M ∈ C ( Φ ) , then Serre dim R [ M ] ≤ d . If r ≤ 3 , then Serre dim R [ i n t ( M ) ] ≤ d . If M ⊂ Z + 2.
Evolving Dimensions of Integral Education
Judie Gaffin Wexler
2011-01-01
This article explores the concept of integral education as a way to prepare students for the complex, rapidly changing global environment in which they will be living and working. It contends that education must help students focus both internally and externally if they are to be effectively prepared. The experience of the California Institute of Integral Studies is used as a case study to discuss key dimensions of integral education.
Anomalous dimension in three-dimensional semiclassical gravity
International Nuclear Information System (INIS)
Alesci, Emanuele; Arzano, Michele
2012-01-01
The description of the phase space of relativistic particles coupled to three-dimensional Einstein gravity requires momenta which are coordinates on a group manifold rather than on ordinary Minkowski space. The corresponding field theory turns out to be a non-commutative field theory on configuration space and a group field theory on momentum space. Using basic non-commutative Fourier transform tools we introduce the notion of non-commutative heat-kernel associated with the Laplacian on the non-commutative configuration space. We show that the spectral dimension associated to the non-commutative heat kernel varies with the scale reaching a non-integer value smaller than three for Planckian diffusion scales.
Engin, Doruk; Chuang, Ti; Litvinovitch, Slava; Storm, Mark
2017-08-01
Fibertek has developed and demonstrated an ideal high-power; low-risk; low-size, weight, and power (SWaP) 2051 nm laser design meeting the lidar requirements for satellite-based global measurement of carbon dioxide (CO2). The laser design provides a path to space for either a coherent lidar approach being developed by NASA Jet Propulsion Laboratory (JPL)1,2 or an Integrated Path Differential Lidar (IPDA) approach developed by Harris Corp using radio frequency (RF) modulation and being flown as part of a NASA Earth Venture Suborbital Mission—NASA's Atmospheric Carbon and Transport - America.3,4 The thulium (Tm) fiber laser amplifies a architecture, and design margins can support a coherent or IPDA lidar 10-year space mission. With follow-on funding Fibertek can adapt an existing space-based Technology Readiness Level 6 (TRL-6), 20 W erbium fiber laser package for this Tm design and enable a near-term space mission with an electrical-to-optical (e-o) efficiency of sustains its highly efficient operation for a temperature range of 5-40°C. The absence of stimulated Brillouin scattering (SBS) for the narrow linewidth amplification shows promise for further power scaling.
Wave equations in higher dimensions
Dong, Shi-Hai
2011-01-01
Higher dimensional theories have attracted much attention because they make it possible to reduce much of physics in a concise, elegant fashion that unifies the two great theories of the 20th century: Quantum Theory and Relativity. This book provides an elementary description of quantum wave equations in higher dimensions at an advanced level so as to put all current mathematical and physical concepts and techniques at the reader’s disposal. A comprehensive description of quantum wave equations in higher dimensions and their broad range of applications in quantum mechanics is provided, which complements the traditional coverage found in the existing quantum mechanics textbooks and gives scientists a fresh outlook on quantum systems in all branches of physics. In Parts I and II the basic properties of the SO(n) group are reviewed and basic theories and techniques related to wave equations in higher dimensions are introduced. Parts III and IV cover important quantum systems in the framework of non-relativisti...
Memory effect for particle scattering in odd spacetime dimensions
Satishchandran, Gautam; Wald, Robert M.
2018-01-01
We investigate the gravitational memory effect for linearized perturbations off of Minkowski space in odd spacetime dimensions d by examining the effects of gravitational radiation from classical point particle scattering. We also investigate analogous memory effects for electromagnetic and scalar radiation. We find that there is no gravitational memory effect in all odd dimensions. For scalar and electromagnetic fields, there is no memory effect for d ≥7 ; for d =3 there is an infinite momentum memory effect, whereas for d =5 there is no momentum memory effect but the displacement of a test particle will grow unboundedly with time. Our results are further elucidated by analyzing the memory effect for any slowly moving source of compact spatial support in odd dimensions.
CKM pattern from localized generations in extra dimension
International Nuclear Information System (INIS)
Matti, C.
2006-01-01
We revisit the issue of the quark masses and mixing angles in the framework of large extra dimension. We consider three identical standard model families resulting from higher-dimensional fields localized on different branes embedded in a large extra dimension. Furthermore we use a decaying profile in the bulk different form previous works. With the Higgs field also localized on a different brane, the hierarchy of masses between the families results from their different positions in the extra space. When the left-handed doublet and the right-handed singlets are localized with different couplings on the branes, we found a set of brane locations in one extra dimension which leads to the correct quark masses and mixing angles with the sufficient strength of CP-violation. We see that the decaying profile of the Higgs field plays a crucial role for producing the hierarchies in a rather natural way. (orig.)
On the selection of dimension reduction techniques for scientific applications
Energy Technology Data Exchange (ETDEWEB)
Fan, Y J; Kamath, C
2012-02-17
Many dimension reduction methods have been proposed to discover the intrinsic, lower dimensional structure of a high-dimensional dataset. However, determining critical features in datasets that consist of a large number of features is still a challenge. In this paper, through a series of carefully designed experiments on real-world datasets, we investigate the performance of different dimension reduction techniques, ranging from feature subset selection to methods that transform the features into a lower dimensional space. We also discuss methods that calculate the intrinsic dimensionality of a dataset in order to understand the reduced dimension. Using several evaluation strategies, we show how these different methods can provide useful insights into the data. These comparisons enable us to provide guidance to a user on the selection of a technique for their dataset.
Dual projection and self duality in three dimensions
International Nuclear Information System (INIS)
Banerjee, Rabin; Wotzasek, Clovis
2000-01-01
Full text follows: We discuss the notion of duality and self duality in the context of the dual projection operation that creates an internal space of potentials. This technique is applicable to both even and odd dimensions. We derive the appropriate invariant actions, discuss the symmetry groups and their proper generators. In particular, the novel concept of duality symmetry and self duality in Maxwell theory in (2+1) dimensions is analysed in details. The corresponding action is a 3D version of the familiar duality symmetric electromagnetic theory in 4D. Finally, the duality symmetric actions in the different dimensions constructed here manifest both the SO(2) and Z 2 symmetries, contrary to conventional results. (author)
DEFF Research Database (Denmark)
Østergaard, Dorte Skaarup; Svendsen, Svend
2017-01-01
. These benefits can be maximized if district heating temperatures are lowered as much as possible. In this paper we report on a project where 18 Danish single-family houses from the 1980s were supplied by ultra-low temperature district heating with a supply temperature as low as 45 degrees C for the main part...... heating return temperatures in the houses were analysed for different times of the year. The study found that existing Danish single-family houses from the 1980s can be heated with supply temperatures as low as 45 degrees C for the main part of the year. Both simulation models and test measurements showed...
The necessity for a time local dimension in systems with time-varying attractors
DEFF Research Database (Denmark)
Særmark, Knud H; Ashkenazy, Y; Levitan, J
1997-01-01
We show that a simple non-linear system for ordinary differential equations may possess a time-varying attractor dimension. This indicates that it is infeasible to characterize EEG and MEG time series with a single time global dimension. We suggest another measure for the description of non...
Low dimensional representation of face space by face-selective inferior temporal neurons.
Salehi, Sina; Dehaqani, Mohammad-Reza A; Esteky, Hossein
2017-05-01
The representation of visual objects in primate brain is distributed and multiple neurons are involved in encoding each object. One way to understand the neural basis of object representation is to estimate the number of neural dimensions that are needed for veridical representation of object categories. In this study, the characteristics of the match between physical-shape and neural representational spaces in monkey inferior temporal (IT) cortex were evaluated. Specifically, we examined how the number of neural dimensions, stimulus behavioral saliency and stimulus category selectivity of neurons affected the correlation between shape and neural representational spaces in IT cortex. Single-unit recordings from monkey IT cortex revealed that there was a significant match between face space and its neural representation at lower neural dimensions, whereas the optimal match for the non-face objects was observed at higher neural dimensions. There was a statistically significant match between the face and neural spaces only in the face-selective neurons, whereas a significant match was observed for non-face objects in all neurons regardless of their category selectivity. Interestingly, the face neurons showed a higher match for the non-face objects than for the faces at higher neural dimensions. The optimal representation of face space in the responses of the face neurons was a low dimensional map that emerged early (~150 ms post-stimulus onset) and was followed by a high dimensional and relatively late (~300 ms) map for the non-face stimuli. These results support a multiplexing function for the face neurons in the representation of very similar shape spaces, but with different dimensionality and timing scales. © 2017 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.
Al Amri, Mohammad D; Al-Johany, Sulieman S; Al-Qarni, Mohammed N; Al-Bakri, Ahmed S; Al-Maflehi, Nassr S; Abualsaud, Haythem S
2018-02-01
The detrimental effect of extruded excess cement on peri-implant tissue has been well documented. Although several techniques have been proposed to reduce this effect by decreasing the amount of extruded cement, how the space size of the abutment screw access channel (SAC) affects the amount of extruded cement and marginal accuracy is unclear. The purpose of this in vitro study was to evaluate the effect of the size of the unfilled space of the abutment SAC on the amount of extruded excess cement and the marginal accuracy of zirconia copings. Twelve implant replicas and corresponding standard abutments were attached and embedded in acrylic resin blocks. Computer-aided design and computer-aided manufacturing (CAD-CAM) zirconia copings with a uniform 30-μm cement space were fabricated by 1 dental technician using the standard method. The copings were temporarily cemented 3 times at different sizes of the left space of the SAC as follows: the nonspaced group (NS), in which the entire SAC was completely filled, the 1-mm-spaced group (1MMS), and the 2-mm-spaced group (2MMS). Abutments and crowns were ultrasonically cleaned, steam cleaned, and air-dried. The excess cement was collected and weighed. To measure the marginal accuracy, 20 measurements were made every 18 degrees along the coping margin at ×300 magnification and compared with the pre-cementation readings. One-way ANOVA was calculated to determine whether the amount of extruded excess cement differed among the 3 groups, and the Tukey test was applied for multiple comparisons (α=.05). The mean weights (mg) of extruded excess cement were NS (33.53 ±1.5), 1MMS (22.97 ±5.4), and 2MMS (15.17 ±5.9). Multiple comparisons showed significant differences in the amount of extruded excess cement among the 3 test groups (Pextruded excess cement by 55% in comparison with the nonspaced abutments. However, no effect was found on the marginal accuracy of zirconia copings. Copyright © 2017 Editorial Council for the
New universality class in three dimensions
DEFF Research Database (Denmark)
Codello, A.; Safari, M.; Vacca, G. P.
2017-01-01
We study the Blume-Capel universality class in d=103-ϵ dimensions. The renormalization group flow is extracted by looking at poles in fractional dimension of three loop diagrams using MS. The theory is the only nontrivial universality class which admits an expansion to three dimensions with ϵ=13<......-Capel classes as special cases.......We study the Blume-Capel universality class in d=103-ϵ dimensions. The renormalization group flow is extracted by looking at poles in fractional dimension of three loop diagrams using MS. The theory is the only nontrivial universality class which admits an expansion to three dimensions with ϵ=13...
Acoustical analysis and multiple source auralizations of charismatic worship spaces
Lee, Richard W.
2004-05-01
Because of the spontaneity and high level of call and response, many charismatic churches have verbal and musical communication problems that stem from highly reverberant sound fields, poor speech intelligibility, and muddy music. This research looks at the subjective dimensions of room acoustics perception that affect a charismatic worship space, which is summarized using the acronym RISCS (reverberation, intimacy, strength, coloration, and spaciousness). The method of research is to obtain acoustical measurements for three worship spaces in order to analyze the objective parameters associated with the RISCS subjective dimensions. For the same spaces, binaural room impulse response (BRIR) measurements are done for different receiver positions in order to create an auralization for each position. The subjective descriptors of RISCS are analyzed through the use of listening tests of the three auralized spaces. The results from the measurements and listening tests are analyzed to determine if listeners' perceptions correlate with the objective parameter results, the appropriateness of the subjective parameters for the use of the space, and which parameters seem to take precedent. A comparison of the multi-source auralization to a conventional single-source auralization was done with the mixed down version of the synchronized multi-track anechoic signals.
Dimensional discontinuity in quantum communication complexity at dimension seven
Tavakoli, Armin; Pawłowski, Marcin; Żukowski, Marek; Bourennane, Mohamed
2017-02-01
Entanglement-assisted classical communication and transmission of a quantum system are the two quantum resources for information processing. Many information tasks can be performed using either quantum resource. However, this equivalence is not always present since entanglement-assisted classical communication is sometimes known to be the better performing resource. Here, we show not only the opposite phenomenon, that there exist tasks for which transmission of a quantum system is a more powerful resource than entanglement-assisted classical communication, but also that such phenomena can have a surprisingly strong dependence on the dimension of Hilbert space. We introduce a family of communication complexity problems parametrized by the dimension of Hilbert space and study the performance of each quantum resource. Under an additional assumption of a linear strategy for the receiving party, we find that for low dimensions the two resources perform equally well, whereas for dimension seven and above the equivalence is suddenly broken and transmission of a quantum system becomes more powerful than entanglement-assisted classical communication. Moreover, we find that transmission of a quantum system may even outperform classical communication assisted by the stronger-than-quantum correlations obtained from the principle of macroscopic locality.
Children's comprehension monitoring of multiple situational dimensions of a narrative.
Wassenburg, Stephanie I; Beker, Katinka; van den Broek, Paul; van der Schoot, Menno
Narratives typically consist of information on multiple aspects of a situation. In order to successfully create a coherent representation of the described situation, readers are required to monitor all these situational dimensions during reading. However, little is known about whether these dimensions differ in the ease with which they can be monitored. In the present study, we examined whether children in Grades 4 and 6 monitor four different dimensions (i.e., emotion, causation, time, and space) during reading, using a self-paced reading task containing inconsistencies. Furthermore, to explore what causes failure in inconsistency detection, we differentiated between monitoring processes related to availability and validation of information by manipulating the distance between two pieces of conflicting information. The results indicated that the monitoring processes varied as a function of dimension. Children were able to validate emotional and causal information when it was still active in working memory, but this was not the case for temporal and spatial information. When context and target information were more distant from each other, only emotionally charged information remained available for further monitoring processes. These findings show that the influence of different situational dimensions should be taken into account when studying children's reading comprehension.
Safety of increasing vertical dimension of occlusion: a systematic review.
Abduo, Jaafar
2012-05-01
To review all the literature investigating the implications of increasing the vertical dimension of occlusion (VDO). A comprehensive electronic search was conducted through PubMed with the aid of Boolean operators to combine the following key words: "occlusal vertical dimension," "increasing vertical dimension," "bite raising," "occlusal space," "resting vertical dimension," "rest position," "altered vertical dimension," "mandibular posture," "temporomandibular joint," and "masticatory muscles." The search was limited to peer-reviewed articles written in English and published through August 2011. Further, the literature search was endorsed by manual searching through peer-reviewed journals and reference lists of the selected articles. A total of 902 studies were initially retrieved, but only 9 met the specified inclusion criteria for the review. From the selected studies, four variables were identified to be relevant to the topic of VDO increase: magnitude of VDO increase, method of increasing VDO, occlusion scheme, and the adaptation period. Considering the limitations of this review, it could be concluded that whenever indicated, permanent increase of the VDO is a safe and predictable procedure. Intervention with a fixed restoration is more predictable and results in a higher adaptation level. Negative signs and symptoms were identified, but they were self-limiting. Due to the lack of a well-designed study, further controlled and randomized studies are needed to confirm the outcome of this review.
The matrix nonlinear Schrodinger equation in dimension 2
DEFF Research Database (Denmark)
Zuhan, L; Pedersen, Michael
2001-01-01
In this paper we study the existence of global solutions to the Cauchy problem for the matrix nonlinear Schrodinger equation (MNLS) in 2 space dimensions. A sharp condition for the global existence is obtained for this equation. This condition is in terms of an exact stationary solution of a semi...... of a semilinear elliptic equation. In the scalar case, the MNLS reduces to the well-known cubic nonlinear Schrodinger equation for which existence of solutions has been studied by many authors. (C) 2001 Academic Press.......In this paper we study the existence of global solutions to the Cauchy problem for the matrix nonlinear Schrodinger equation (MNLS) in 2 space dimensions. A sharp condition for the global existence is obtained for this equation. This condition is in terms of an exact stationary solution...
Measuring global well-being inequality: A dimension-by-dimension or multidimensional approach?
Koen Decancq
2011-01-01
This paper investigates the evolution of global well-being inequality between 1980 and 2010 based on three dimensions: income, health and education. I compare two different approaches to the measurement of global well-being inequality: a dimension-by-dimension approach and a multidimensional one. The first approach analyses the dimensions of well-being separately. The inequality of each of these dimensions shows a remarkably different pattern over time. Unfortunately, this dimension-by-dimens...
Songra, Goldie; Clover, Matthew; Atack, Nikki E; Ewings, Paul; Sherriff, Martyn; Sandy, Jonathan R; Ireland, Anthony J
2014-05-01
The aim of this study was to compare the time to initial alignment and extraction space closure using conventional brackets and active and passive self-ligating brackets. One hundred adolescent patients 11 to 18 years of age undergoing maxillary and mandibular fixed appliance therapy after the extraction of 4 premolars were randomized with stratification of 2 age ranges (11-14 and 15-18 years) and 3 maxillomandibular plane angles (high, medium, and low) with an allocation ratio of 1:2:2. Restrictions were applied using a block size of 10. Allocation was to 1 of 3 treatment groups: conventional brackets, active self-ligating, or passive self-ligating brackets. All subjects were treated with the same archwire sequence and space-closing mechanics in a district general hospital setting. The trial was a 3-arm parallel design. Labial-segment alignment and space closure were measured on study models taken every 12 weeks throughout treatment. All measurements were made by 1 operator who was blinded to bracket type. The patients and other operators were not blinded to bracket type during treatment. Ninety-eight patients were followed to completion of treatment (conventional, n = 20; active self-ligating brackets, n = 37; passive self-ligating brackets, n = 41). The data were analyzed using linear mixed models and demonstrated a significant effect of bracket type on the time to initial alignment (P = 0.001), which was shorter with the conventional brackets than either of the self-ligating brackets. Sidak's adjustment showed no significant difference in effect size (the difference in average response in millimeters) between the active and passive self-ligating brackets (the results are presented as effect size, 95% confidence intervals, probabilities, and intraclass correlation coefficients) (-0.42 [-1.32, 0.48], 0.600, 0.15), but the conventional bracket was significantly different from both of these (-1.98 [-3.19, -0.76], 0.001, 0.15; and -1.56 [-2.79, -0.32], 0.001, 0
Spontaneous compactification to homogeneous spaces
International Nuclear Information System (INIS)
Mourao, J.M.
1988-01-01
The spontaneous compactification of extra dimensions to compact homogeneous spaces is studied. The methods developed within the framework of coset space dimensional reduction scheme and the most general form of invariant metrics are used to find solutions of spontaneous compactification equations
International Nuclear Information System (INIS)
Nguyen, Q H; Choi, S B
2010-01-01
This paper presents an optimal design of a magnetorheological (MR) brake for a middle-sized passenger car which can replace a conventional hydraulic disc-type brake. In the optimization, the required braking torque, the temperature due to zero-field friction of MR fluid, the mass of the brake system and all significant geometric dimensions are considered. After describing the configuration, the braking torque of the proposed MR brake is derived on the basis of the field-dependent Bingham and Herschel–Bulkley rheological model of the MR fluid. The optimal design of the MR brake is then analyzed taking into account available space, mass, braking torque and steady heat generated by zero-field friction torque of the MR brake. The optimization procedure based on the finite element analysis integrated with an optimization tool is proposed to obtain optimal geometric dimensions of the MR brake. Based on the proposed procedure, optimal solutions of single and multiple disc-type MR brakes featuring different types of MR fluid are achieved. From the results, the most effective MR brake for the middle-sized passenger car is identified and some discussions on the performance improvement of the optimized MR brake are described
Nguyen, Q. H.; Choi, S. B.
2010-11-01
This paper presents an optimal design of a magnetorheological (MR) brake for a middle-sized passenger car which can replace a conventional hydraulic disc-type brake. In the optimization, the required braking torque, the temperature due to zero-field friction of MR fluid, the mass of the brake system and all significant geometric dimensions are considered. After describing the configuration, the braking torque of the proposed MR brake is derived on the basis of the field-dependent Bingham and Herschel-Bulkley rheological model of the MR fluid. The optimal design of the MR brake is then analyzed taking into account available space, mass, braking torque and steady heat generated by zero-field friction torque of the MR brake. The optimization procedure based on the finite element analysis integrated with an optimization tool is proposed to obtain optimal geometric dimensions of the MR brake. Based on the proposed procedure, optimal solutions of single and multiple disc-type MR brakes featuring different types of MR fluid are achieved. From the results, the most effective MR brake for the middle-sized passenger car is identified and some discussions on the performance improvement of the optimized MR brake are described.
Geometric Langlands From Six Dimensions
Witten, Edward
2010-01-01
Geometric Langlands duality is usually formulated as a statement about Riemann surfaces, but it can be naturally understood as a consequence of electric-magnetic duality of four-dimensional gauge theory. This duality in turn is naturally understood as a consequence of the existence of a certain exotic supersymmetric conformal field theory in six dimensions. The same six-dimensional theory also gives a useful framework for understanding some recent mathematical results involving a counterpart of geometric Langlands duality for complex surfaces. (This article is based on a lecture at the Raoul Bott celebration, Montreal, June 2008.)
Fractal dimension of bioconvection patterns
Noever, David A.
1990-01-01
Shallow cultures of the motile algal strain, Euglena gracilis, were concentrated to 2 x 10 to the 6th organisms per ml and placed in constant temperature water baths at 24 and 38 C. Bioconvective patterns formed an open two-dimensional structure with random branches, similar to clusters encountered in the diffusion-limited aggregation (DLA) model. When averaged over several example cultures, the pattern was found to have no natural length scale, self-similar branching, and a fractal dimension (d about 1.7). These agree well with the two-dimensional DLA.
Brenner, B; Yu, L C
1985-01-01
Equatorial x-ray diffraction patterns were obtained from single skinned rabbit psoas fibers during various degrees of activation under isometric conditions at ionic strength 170 mM and 6-9 degrees C. By direct calcium activation, contraction was homogeneous throughout the preparation, and by using a cycling technique (Brenner, 1983) integrity of the fiber was maintained even during prolonged steady activation. The intensity ratio of the two innermost reflections I11/I10, and the normalized in...
Gravitational actions in two dimensions and the Mabuchi functional
Energy Technology Data Exchange (ETDEWEB)
Ferrari, Frank, E-mail: frank.ferrari@ulb.ac.be [Service de Physique Theorique et Mathematique, Universite Libre de Bruxelles and International Solvay Institutes, Campus de la Plaine, CP 231, B-1050 Bruxelles (Belgium); Klevtsov, Semyon, E-mail: semyon.klevtsov@ulb.ac.be [Service de Physique Theorique et Mathematique, Universite Libre de Bruxelles and International Solvay Institutes, Campus de la Plaine, CP 231, B-1050 Bruxelles (Belgium); Zelditch, Steve, E-mail: zelditch@math.northwestern.edu [Department of Mathematics, Northwestern University, Evanston, IL 60208 (United States)
2012-06-21
The Mabuchi energy is an interesting geometric functional on the space of Kaehler metrics that plays a crucial role in the study of the geometry of Kaehler manifolds. We show that this functional, as well as other related geometric actions, contribute to the effective gravitational action when a massive scalar field is coupled to gravity in two dimensions in a small mass expansion. This yields new theories of two-dimensional quantum gravity generalizing the standard Liouville models.
Constructing unified models based on E8 in ten dimensions
International Nuclear Information System (INIS)
Kapetanakis, D.
1992-01-01
We examine the virtues and difficulties of the attempts to construct realistic four-dimensional models from a gauge theory based on E 8 and defined in ten dimensions. The four-dimensional theories are obtained using the coset space dimensional reduction scheme. Some of our points and in particular the proposed mechanism for supersymmetry breaking might be useful in other dimensional reduction schemes. (orig.)
External dimension of Ukraine’s security policy
O. S. Vonsovych
2015-01-01
Investigation of the external dimension of security policy of Ukraine is stipulated for the need to analyse the current state of relations with organizations such as the Organization for Security and Co-operation in Europe and The Collective Security Treaty Organization, and relations within the Common European Security and Defence Policy. Ukraine’s European Integration means inclusion in the global space security with countries that it shares common values and principles. It does not exclude...
Personality dimensions and disorders in pathological gambling
DEFF Research Database (Denmark)
Odlaug, Brian Lawrence; Schreiber, Liana R N; Grant, Jon E
2013-01-01
This review presents the most current research in personality dimensions and disorders with respect to pathological gambling.......This review presents the most current research in personality dimensions and disorders with respect to pathological gambling....
Gravity theories in more than four dimensions
International Nuclear Information System (INIS)
Zumino, B.
1985-03-01
String theories suggest particular forms for gravity interactions in higher dimensions. We consider an interesting class of gravity theories in more than four dimensions, clarify their geometric meaning and discuss their special properties. 9 refs
Enumeration of Combinatorial Classes of Single Variable Complex Polynomial Vector Fields
DEFF Research Database (Denmark)
Dias, Kealey
A vector field in the space of degree d monic, centered single variable complex polynomial vector fields has a combinatorial structure which can be fully described by a combinatorial data set consisting of an equivalence relation and a marked subset on the integers mod 2d-2, satisfying certain...... in a valid way. We first enumerate all combinatorial classes with respect to degree d, and then we enumerate the combinatorial classes having a specific dimension q in parameter space. In both cases, a recursion equation and implicit expressions for the algebraic generating functions are calculated...
Dimension changing phase transitions in instanton crystals
International Nuclear Information System (INIS)
Kaplunovsky, Vadim; Sonnenschein, Jacob
2014-01-01
We investigate lattices of instantons and the dimension-changing transitions between them. Our ultimate goal is the 3D→4D transition, which is holographically dual to the phase transition between the baryonic and the quarkyonic phases of cold nuclear matter. However, in this paper (just as in http://dx.doi.org/10.1007/JHEP11(2012)047) we focus on lower dimensions — the 1D lattice of instantons in a harmonic potential V∝M 2 2 x 2 2 +M 3 2 x 2 2 +M 4 2 x 4 2 , and the zigzag-shaped lattice as a first stage of the 1D→2D transition. We prove that in the low- and moderate-density regimes, interactions between the instantons are dominated by two-body forces. This drastically simplifies finding the ground state of the instantons’ orientations, so we made a numeric scan of the whole orientation space instead of assuming any particular ansatz. We find that depending on the M 2 /M 3 /M 4 ratios, the ground state of instanton orientations can follow a wide variety of patterns. For the straight 1D lattices, we found orientations periodically running over elements of a ℤ 2 , Klein, prismatic, or dihedral subgroup of the SU(2)/ℤ 2 , as well as irrational but link-periodic patterns. For the zigzag-shaped lattices, we detected 4 distinct orientation phases — the anti-ferromagnet, another abelian phase, and two non-abelian phases. Allowing the zigzag amplitude to vary as a function of increasing compression force, we obtained the phase diagrams for the straight and zigzag-shaped lattices in the (force,M 3 /M 4 ), (chemical potential,M 3 /M 4 ), and (density,M 3 /M 4 ) planes. Some of the transitions between these phases are second-order while others are first-order. Our techniques can be applied to other types of non-abelian crystals
Directory of Open Access Journals (Sweden)
Aida CÎMPEANU
2011-11-01
Full Text Available Because Europe is characterized by the coexistence of several cultures whose characteristics have both similarities and differences but appreciable, the results of researchers in this regard are different from each other, this distinction is often made based on the prevailing values of that culture , which determines the orientation of the country for a certain system, management style or to a specific profile manager. A particularly important role in characterizing cultural factors play European management, each differing from the other culture as module in addressing various fundamental issues that characterize that society. These issues can be characterized by certain general cultural dimensions that Hofstede defines them as aspects of a culture that can be measured in relation to other cultures. The differences between management systems in European countries (mainly EU countries in the context of this article, the study is based on four cultural dimensions of Hofstede model (power distance, individualism vs. collectivism, uncertainty avoidance, femininity vs. masculinity and change scores recorded for these dimensions in each country. Dimensions considered primarily affect organizational culture which in turn significantly influence the development and performance of the organization and its members, management practices and policies.Data from Hofstede's study reinforce and support the claim that European countries can be grouped systematically cultural groups (Nordic countries, Latin, Germanic, Anglo-Saxon, Eastern Europe that allow significant interpretation in terms of management organization, and that can speak of a typical single European culture but you can see all dimensions of cultural differences taken into account.
Optimization of MNSR upper reflector material and dimensions
International Nuclear Information System (INIS)
Albarhoum, M.
2007-04-01
Calculations for the optimization of the material and dimensions of the Syrian MNSR was performed. Calculations showed that the considerably important reflectors in this case are Beryllium, Heavy water and Graphite. Dimensions of the reflector cannot any way exceed the Shim Tray dimensions. Two different ways of filling the Shim Tray with the reflector material were established: 1- the radial filling mode, and 2- the axial mode. Both modes can be performed using single sectors or cumulative ones. The axial mode proved to be better than the radial one. The axial cumulative mode proved to be more efficient than the single axial one. The axial cumulative mode was studied from two points of view; the neutronic and the economic ones. From the neutronic point of view the beryllium proved to be the best reflector, and the best dimensions were found to coincide with a thickness equal to 0.11235 cm with the bottom end being 0.4494 cm distant from the bottom of the Shim Tray. From the economic point of view it was found that the cost of the reactivity unit is the smallest when the Graphite is used. Results of this study can be applied directly to the Syrian MNSR since fabrication of any plastic containment for the reflector can easily be achieved. This is because the reactivity worth resulting from mass unit of the reflector varies depending on its position positions in the Shim Tray.(author)
Energy Technology Data Exchange (ETDEWEB)
Noll, Daniel [Goethe Univ., Frankfurt (Germany); Stancari, Giulio [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)
2015-11-17
An electron lens is planned for the Fermilab Integrable Optics Test Accelerator as a nonlinear element for integrable dynamics, as an electron cooler, and as an electron trap to study space-charge compensation in rings. We present the main design principles and constraints for nonlinear integrable optics. A magnetic configuration of the solenoids and of the toroidal section is laid out. Singleparticle tracking is used to optimize the electron path. Electron beam dynamics at high intensity is calculated with a particle-in-cell code to estimate current limits, profile distortions, and the effects on the circulating beam. In the conclusions, we summarize the main findings and list directions for further work.
Chemla, D. S.; Bar-Joseph, I.; Klingshirn, C.; Miller, D. A. B.; Kuo, J. M.
1987-03-01
Absorption switching in a semiconductor quantum well by electrically varying the charge density in the quantum well conducting channel of a selectively doped heterostructure transistor is reported for the first time. The phase-space absorption quenching (PAQ) is observed at room temperature in an InGaAs/InAlAs grown on InP FET, and it shows large absorption coefficient changes with relatively broad spectral bandwidth. This PAQ is large enough to be used for direct optical determination of the logic state of the FET.
Protein Adsorption in Three Dimensions
Vogler, Erwin A.
2011-01-01
Recent experimental and theoretical work clarifying the physical chemistry of blood-protein adsorption from aqueous-buffer solution to various kinds of surfaces is reviewed and interpreted within the context of biomaterial applications, especially toward development of cardiovascular biomaterials. The importance of this subject in biomaterials surface science is emphasized by reducing the “protein-adsorption problem” to three core questions that require quantitative answer. An overview of the protein-adsorption literature identifies some of the sources of inconsistency among many investigators participating in more than five decades of focused research. A tutorial on the fundamental biophysical chemistry of protein adsorption sets the stage for a detailed discussion of the kinetics and thermodynamics of protein adsorption, including adsorption competition between two proteins for the same adsorbent immersed in a binary-protein mixture. Both kinetics and steady-state adsorption can be rationalized using a single interpretive paradigm asserting that protein molecules partition from solution into a three-dimensional (3D) interphase separating bulk solution from the physical-adsorbent surface. Adsorbed protein collects in one-or-more adsorbed layers, depending on protein size, solution concentration, and adsorbent surface energy (water wettability). The adsorption process begins with the hydration of an adsorbent surface brought into contact with an aqueous-protein solution. Surface hydration reactions instantaneously form a thin, pseudo-2D interface between the adsorbent and protein solution. Protein molecules rapidly diffuse into this newly-formed interface, creating a truly 3D interphase that inflates with arriving proteins and fills to capacity within milliseconds at mg/mL bulk-solution concentrations CB. This inflated interphase subsequently undergoes time-dependent (minutes-to-hours) decrease in volume VI by expulsion of either-or-both interphase water and
Rings with finite Gorenstein injective dimension
DEFF Research Database (Denmark)
Holm, Henrik Granau
2004-01-01
In this paper we prove that for any associative ring R, and for any left R-module M with nite projective dimension, the Gorenstein injective dimension GidRM equals the usual injective dimension idRM. In particular, if GidRR is nite, then also idRR is nite, and thus R is Gorenstein (provided that ...
Fractal Dimension and the Cantor Set
Indian Academy of Sciences (India)
IAS Admin
1000. RESONANCE ⎜ November 2014. GENERAL ⎜ ARTICLE. Fractal Dimension and the Cantor Set. Shailesh A Shirali. Keywords. Dimension, topological dimen- sion, Hausdorff–Besicovitch di- mension, fractal dimension, fractal, Cantor set, Sierpinski triangle, Koch curve. Shailesh Shirali is. Director of Sahyadri School.
[Space perception: the history and its significance for art].
Norn, Mogens
2002-01-01
Some aspects of the opthalmologic history of Denmark are briefly mentioned. Lens extraction in 1667 in Copenhagen, Edmund Hansen Gruts stereoophtalmoscopy in 1857, Ludvig Panums area in 1858 (single vision) space perception and outside this area double vision), squint treatment, Marius Tschernings periscopic spectacle lenses, Henning Rønnes stereoortograph and keiroscope and Gerhard Rønnes stereoscope. Space perception depends mostly on binocular function (convergens), but in fact some space perception occurs in vision due to perspective, accommodation, parallaxe, blurring, colours and shadows. The Danisk Poet, Hans Christian Andersen, has in his novels mentioned latent squint. The German poet Rainer Maria Rilke was much interested in perspective in connection with the development of impressionism, especially Paul Cézanne. Rilke in his later period developed the view that concentration on perspective removed those essential aspects from the world, in which he found God or a fourth dimension, as exemplified in the presence of ghosts.
Imaging Single ZnO Vertical Nanowire Laser Cavities using UV-Laser Scanning Confocal Microscopy
Energy Technology Data Exchange (ETDEWEB)
Gargas, D.J.; Toimil-Molares, M.E.; Yang, P.
2008-11-17
We report the fabrication and optical characterization of individual ZnO vertical nanowire laser cavities. Dilute nanowire arrays with interwire spacing>10 ?m were produced by a modified chemical vapor transport (CVT) method yielding an ideal platform for single nanowire imaging and spectroscopy. Lasing characteristics of a single vertical nanowire are presented, as well as high-resolution photoluminescence imaging by UV-laser scanning confocal microscopy. In addition, three-dimensional (3D) mapping of the photoluminescence emission performed in both planar and vertical dimensions demonstrates height-selective imaging useful for vertical nanowires and heteronanostructures emerging in the field of optoelectronics and nanophotonics.
Examining the Underlying Dimensions of Morphological Awareness and Vocabulary Knowledge
Spencer, Mercedes; Muse, Andrea; Wagner, Richard K.; Foorman, Barbara; Petscher, Yaacov; Schatschneider, Christopher; Tighe, Elizabeth L.; Bishop, M. Denise
2015-01-01
We report results from two studies on the underlying dimensions of morphological awareness and vocabulary knowledge in elementary-aged children. In Study 1, 99 fourth-grade students were given multiple measures of morphological awareness and vocabulary. A single factor accounted for individual differences in all morphology and vocabulary assessments. Study 2 extended these results by giving 90 eighth-grade students expanded measures of vocabulary and morphology that assessed (a) definitional ...
VC-dimension of univariate decision trees.
Yildiz, Olcay Taner
2015-02-01
In this paper, we give and prove the lower bounds of the Vapnik-Chervonenkis (VC)-dimension of the univariate decision tree hypothesis class. The VC-dimension of the univariate decision tree depends on the VC-dimension values of its subtrees and the number of inputs. Via a search algorithm that calculates the VC-dimension of univariate decision trees exhaustively, we show that our VC-dimension bounds are tight for simple trees. To verify that the VC-dimension bounds are useful, we also use them to get VC-generalization bounds for complexity control using structural risk minimization in decision trees, i.e., pruning. Our simulation results show that structural risk minimization pruning using the VC-dimension bounds finds trees that are more accurate as those pruned using cross validation.
Psychological dimensions of Energy Conservation
Directory of Open Access Journals (Sweden)
Tonello, Graciela
2012-12-01
Full Text Available One of the most serious current environmental problems is the depletion of non renewable natural resources. The vast majority of our daily actions involve the consumption of energy and they increase the problem. Environmental psychology studies the psychological motivations that determine pro-ecological behaviour. In this context the aim of this review was to determine which psychological models and variables are better descriptors of residential energy conservation, comparing the predictive power of different models related to behaviour, residential consumption as well as to the acceptability of energy policies. Results suggest that energy saving is mainly linked to altruistic motivations, followed by egoistic reasons and in a minor way to environmental concerns. People would act according to these dimensions when contextual conditions are perceived as appropriate.
The spatial dimensions of innovation
DEFF Research Database (Denmark)
Lorentzen, Anne
2005-01-01
by the common perceptions, and the institutional infrastructure prevailing in the (local)society. In Poland the latter is closely connected with the process of transition since 1990. The paper reports from a study among Polish manufacturing companies. It categorises the types of innovation prevailing......The paper discusseses the spatial dimensions of innovation in Polish manufacturing companies. The conceptual framework of the paper is an understanding of social networks as a potential resource of the company, whether they are internal or external. Whether the company benefits from the potential...... in the companies and detects the role of networks in the innovation process of the companies. To what extend do the companies draw on external networks, on what points of the innovation process are the networks involved, what kind of networks are involved, and not least, what are the spatial characteristics...
Human dimension of strategic partnerships
Directory of Open Access Journals (Sweden)
Petković Mirjana M.
2004-01-01
Full Text Available This paper aims to point to the widespread practice of neglecting behavioral aspects of different forms of fusions and integrations of enterprises that have emerged in the process of privatization through strategic partnerships with foreign companies among Serbian enterprises. The initial hypothesis in this paper is that the process of privatization, restructuring and transformation in Serbian enterprises cannot be completely successful and equally advantageous for all the subjects involved if there is no concern for human dimension of these processes. Without this concern there is a possibility for behavioral problems to arise, and the only way to resolve them is through post festum respecting and introducing elements that should never have been neglected in the first place. This paper refers to the phenomenon of collision of cultures and the ways of resolving it while forming strategic partnerships.
Quaternionic geometry in dimension eight
DEFF Research Database (Denmark)
Conti, Diego; Madsen, Thomas Bruun; Salamon, Simon
We describe the 8-dimensional Wolf spaces as cohomogeneity one SU(3)-manifolds, and discover perturbations of the quaternion-kaehler metric on the simply-connected 8-manifold G_2/SO(4) that carry a closed fundamental 4-form but are not Einstein....
The Spatial Dimension of Theatre.
Longman, Stanley Vincent
1981-01-01
Analyzes the use of physical and imagined space and time in three plays. Describes how these features interact, assume dramatic force, and augment the tension, irony, and meaning of the play. The plays used are Chekhov's "The Three Sisters," Moliere's "Tartuffe," and Stoppard's "Rosencrantz and Guildenstern Are Dead." (JMF)
Compiler validates units and dimensions
Levine, F. E.
1980-01-01
Software added to compiler for automated test system for Space Shuttle decreases computer run errors by providing offline validation of engineering units used system command programs. Validation procedures are general, though originally written for GOAL, a free-form language that accepts "English-like" statements, and may be adapted to other programming languages.