WorldWideScience

Sample records for expansion

  1. Maxillary Expansion

    OpenAIRE

    Agarwal, Anirudh; Mathur, Rinku

    2010-01-01

    ABSTRACT Maxillary transverse discrepancy usually requires expansion of the palate by a combination of orthopedic and orthodontic tooth movements. Three expansion treatment modalities are used today: rapid maxillary expansion, slow maxillary expansion and surgically assisted maxillary expansion.This article aims to review the maxillary expansion by all the three modalities and a brief on commonly used appliances.

  2. expansion method

    Indian Academy of Sciences (India)

    In this paper, we shall apply the (G /G)-expansion method to obtain the exact travelling wave solution of the two-dimensional ... In §3, we apply our method to the mentioned equations. In §4, some conclusions are ..... The exact solution obtained by this method can be used to check computer codes or as initial condition for ...

  3. Bridges Expansion Joints

    OpenAIRE

    Sergey W. Kozlachkow

    2012-01-01

    The survey is concerned with the expansion joints, used in bridge constructions to compensate medium and significant operational linear and spatial displacements between adjacent spans or between bridge span and pier. The analysis of design features of these types of expansion joints, their advantages and disadvantages, based on operational experience justified the necessity to design constructions, meeting the modern demands imposed to expansion joints.

  4. On skin expansion.

    Science.gov (United States)

    Pamplona, Djenane C; Velloso, Raquel Q; Radwanski, Henrique N

    2014-01-01

    This article discusses skin expansion without considering cellular growth of the skin. An in vivo analysis was carried out that involved expansion at three different sites on one patient, allowing for the observation of the relaxation process. Those measurements were used to characterize the human skin of the thorax during the surgical process of skin expansion. A comparison between the in vivo results and the numerical finite elements model of the expansion was used to identify the material elastic parameters of the skin of the thorax of that patient. Delfino's constitutive equation was chosen to model the in vivo results. The skin is considered to be an isotropic, homogeneous, hyperelastic, and incompressible membrane. When the skin is extended, such as with expanders, the collagen fibers are also extended and cause stiffening in the skin, which results in increasing resistance to expansion or further stretching. We observed this phenomenon as an increase in the parameters as subsequent expansions continued. The number and shape of the skin expanders used in expansions were also studied, both mathematically and experimentally. The choice of the site where the expansion should be performed is discussed to enlighten problems that can lead to frustrated skin expansions. These results are very encouraging and provide insight into our understanding of the behavior of stretched skin by expansion. To our knowledge, this study has provided results that considerably improve our understanding of the behavior of human skin under expansion. Copyright © 2013 Elsevier Ltd. All rights reserved.

  5. Bridges Expansion Joints

    Directory of Open Access Journals (Sweden)

    Sergey W. Kozlachkow

    2012-05-01

    Full Text Available The survey is concerned with the expansion joints, used in bridge constructions to compensate medium and significant operational linear and spatial displacements between adjacent spans or between bridge span and pier. The analysis of design features of these types of expansion joints, their advantages and disadvantages, based on operational experience justified the necessity to design constructions, meeting the modern demands imposed to expansion joints.

  6. Bridges Expansion Joints

    National Research Council Canada - National Science Library

    Sergey W. Kozlachkow

    2012-01-01

    .... The analysis of design features of these types of expansion joints, their advantages and disadvantages, based on operational experience justified the necessity to design constructions, meeting...

  7. Conformal expansions and renormalons

    CERN Document Server

    Brodsky, S J; Grunberg, G; Rathsman, J; Brodsky, Stanley J.; Gardi, Einan; Grunberg, Georges; Rathsman, Johan

    2001-01-01

    The coefficients in perturbative expansions in gauge theories are factoriallyincreasing, predominantly due to renormalons. This type of factorial increaseis not expected in conformal theories. In QCD conformal relations betweenobservables can be defined in the presence of a perturbative infraredfixed-point. Using the Banks-Zaks expansion we study the effect of thelarge-order behavior of the perturbative series on the conformal coefficients.We find that in general these coefficients become factorially increasing.However, when the factorial behavior genuinely originates in a renormalonintegral, as implied by a postulated skeleton expansion, it does not affect theconformal coefficients. As a consequence, the conformal coefficients willindeed be free of renormalon divergence, in accordance with previousobservations concerning the smallness of these coefficients for specificobservables. We further show that the correspondence of the BLM method with theskeleton expansion implies a unique scale-setting procedure. Th...

  8. Resonant state expansions

    Energy Technology Data Exchange (ETDEWEB)

    Lind, P.

    1993-02-01

    The completeness properties of the discrete set of bound state, virtual states and resonances characterizing the system of a single nonrelativistic particle moving in a central cutoff potential is investigated. From a completeness relation in terms of these discrete states and complex scattering states one can derive several Resonant State Expansions (RSE). It is interesting to obtain purely discrete expansion which, if valid, would significantly simplify the treatment of the continuum. Such expansions can be derived using Mittag-Leffler (ML) theory for a cutoff potential and it would be nice to see if one can obtain the same expansions starting from an eigenfunction theory that is not restricted to a finite sphere. The RSE of Greens functions is especially important, e.g. in the continuum RPA (CRPA) method of treating giant resonances in nuclear physics. The convergence of RSE is studied in simple cases using square well wavefunctions in order to achieve high numerical accuracy. Several expansions can be derived from each other by using the theory of analytic functions and one can the see how to obtain a natural discretization of the continuum. Since the resonance wavefunctions are oscillating with an exponentially increasing amplitude, and therefore have to be interpreted through some regularization procedure, every statement made about quantities involving such states is checked by numerical calculations.Realistic nuclear wavefunctions, generated by a Wood-Saxon potential, are used to test also the usefulness of RSE in a realistic nuclear calculation. There are some fundamental differences between different symmetries of the integral contour that defines the continuum in RSE. One kind of symmetry is necessary to have an expansion of the unity operator that is idempotent. Another symmetry must be used if we want purely discrete expansions. These are found to be of the same form as given by ML. (29 refs.).

  9. Virial Expansion Bounds

    Science.gov (United States)

    Tate, Stephen James

    2013-10-01

    In the 1960s, the technique of using cluster expansion bounds in order to achieve bounds on the virial expansion was developed by Lebowitz and Penrose (J. Math. Phys. 5:841, 1964) and Ruelle (Statistical Mechanics: Rigorous Results. Benjamin, Elmsford, 1969). This technique is generalised to more recent cluster expansion bounds by Poghosyan and Ueltschi (J. Math. Phys. 50:053509, 2009), which are related to the work of Procacci (J. Stat. Phys. 129:171, 2007) and the tree-graph identity, detailed by Brydges (Phénomènes Critiques, Systèmes Aléatoires, Théories de Jauge. Les Houches 1984, pp. 129-183, 1986). The bounds achieved by Lebowitz and Penrose can also be sharpened by doing the actual optimisation and achieving expressions in terms of the Lambert W-function. The different bound from the cluster expansion shows some improvements for bounds on the convergence of the virial expansion in the case of positive potentials, which are allowed to have a hard core.

  10. Wake Expansion Models

    DEFF Research Database (Denmark)

    Branlard, Emmanuel Simon Pierre

    2017-01-01

    Different models of wake expansion are presented in this chapter: the 1D momentum theory model, the cylinder analog model and Theodorsen’s model. Far wake models such as the ones from Frandsen or Rathmann or only briefly mentioned. The different models are compared to each other. Results from thi...... this chapter are used in Chap. 16 to link near-wake and far-wake parameters and in Chap. 20 to study the influence of expansion on tip-losses....

  11. Nuclear expansion with excitation

    Energy Technology Data Exchange (ETDEWEB)

    De, J.N. [Saha Institute of Nuclear Physics, 1/AF Bidhannagar, Kolkata 700064 (India); Departament d' Estructura i Constituents de la Materia, Facultat de Fisica, Universitat de Barcelona, Diagonal 647, 08028 Barcelona (Spain); Samaddar, S.K. [Saha Institute of Nuclear Physics, 1/AF Bidhannagar, Kolkata 700064 (India); Vinas, X. [Departament d' Estructura i Constituents de la Materia, Facultat de Fisica, Universitat de Barcelona, Diagonal 647, 08028 Barcelona (Spain); Centelles, M. [Departament d' Estructura i Constituents de la Materia, Facultat de Fisica, Universitat de Barcelona, Diagonal 647, 08028 Barcelona (Spain)]. E-mail: mario@ecm.ub.es

    2006-07-06

    The expansion of an isolated hot spherical nucleus with excitation energy and its caloric curve are studied in a thermodynamic model with the SkM{sup *} force as the nuclear effective two-body interaction. The calted results are shown to compare well with the recent experimental data from energetic nuclear collisions. The fluctuations in temperature and density are also studied. They are seen to build up very rapidly beyond an excitation energy of {approx}9 MeV/u. Volume-conserving quadrupole deformation in addition to expansion indicates, however, nuclear disassembly above an excitation energy of {approx}4 MeV/u.

  12. Uniform gradient expansions

    Directory of Open Access Journals (Sweden)

    Massimo Giovannini

    2015-06-01

    Full Text Available Cosmological singularities are often discussed by means of a gradient expansion that can also describe, during a quasi-de Sitter phase, the progressive suppression of curvature inhomogeneities. While the inflationary event horizon is being formed the two mentioned regimes coexist and a uniform expansion can be conceived and applied to the evolution of spatial gradients across the protoinflationary boundary. It is argued that conventional arguments addressing the preinflationary initial conditions are necessary but generally not sufficient to guarantee a homogeneous onset of the conventional inflationary stage.

  13. AUTO-EXPANSIVE FLOW

    Science.gov (United States)

    Physics suggests that the interplay of momentum, continuity, and geometry in outward radial flow must produce density and concomitant pressure reductions. In other words, this flow is intrinsically auto-expansive. It has been proposed that this process is the key to understanding...

  14. Rethinking expansive learning

    DEFF Research Database (Denmark)

    Kolbæk, Ditte; Lundh Snis, Ulrika

    discussion forum on Google groups, they created new ways of reflecting and learning. We used netnography to select qualitative postings from the online community and expansive learning concepts for data analysis. The findings show how students changed practices of organisational learning...

  15. IKEA's International Expansion

    OpenAIRE

    Harapiak, Clayton

    2013-01-01

    This case concerns a global retailing firm that is dealing with strategic management and marketing issues. Applying a scenario of international expansion, this case provides a thorough analysis of the current business environment for IKEA. Utilizing a variety of methods (e.g. SWOT, PESTLE, McKinsey Matrix) the overall objective is to provide students with the opportunity to apply their research skills and knowledge regarding a highly competitive industry to develop strategic marketing strateg...

  16. Character expansion of matrix integrals

    OpenAIRE

    van de Leur, J. W.; Orlov, A. Yu.

    2016-01-01

    We consider character expansion of tau functions and multiple integrals in characters of orhtogonal and symplectic groups. In particular we consider character expansions of integrals over orthogonal and over symplectic matrices.

  17. Conformal expansions and renormalons

    CERN Document Server

    Gardi, E; Gardi, Einan; Grunberg, Georges

    2001-01-01

    The large-order behaviour of QCD is dominated by renormalons. On the other hand renormalons do not occur in conformal theories, such as the one describing the infrared fixed-point of QCD at small beta_0 (the Banks--Zaks limit). Since the fixed-point has a perturbative realization, all-order perturbative relations exist between the conformal coefficients, which are renormalon-free, and the standard perturbative coefficients, which contain renormalons. Therefore, an explicit cancellation of renormalons should occur in these relations. The absence of renormalons in the conformal limit can thus be seen as a constraint on the structure of the QCD perturbative expansion. We show that the conformal constraint is non-trivial: a generic model for the large-order behaviour violates it. We also analyse a specific example, based on a renormalon-type integral over the two-loop running-coupling, where the required cancellation does occur.

  18. Permissible limit for mandibular expansion.

    Science.gov (United States)

    Motoyoshi, Mitsuru; Shirai, Sawa; Yano, Shinya; Nakanishi, Kotoe; Shimizu, Noriyoshi

    2005-04-01

    In recent years, mandibular expansion has been increasingly performed in conjunction with orthodontic treatment. Lateral tipping of the molars associated with mandibular expansion should, however, be considered, because excessive expansion may result in excessive buccal tooth inclination, which may disturb the occlusal relationship. This study was conducted to quantitatively clarify molar movement during mandibular expansion using the Schwarz appliance to determine the permissible limit of mandibular expansion as a clinical index for inclination movement. Inclinations in the masticatory surface of the first molar and intermolar width were measured before expansion (T1), after expansion (T2), and before edgewise treatment (T3). Lower plaster models from 29 subjects treated with expansion plates were used and compared with models from 11 control subjects with normal occlusion. The average treatment change (T1-T2) in intermolar width was 5.42 mm (standard deviation 1.98), and the average angle of buccal tooth inclination was 10.16 degrees (standard deviation 3.83). No significant correlation was found between age prior to treatment and the treatment period when they were compared with the intermolar width increments and inclination angles. There was a significant positive correlation between retention duration and the amount of expansion. The regression coefficient of the angle of buccal tooth inclination during expansion to the increment of the intermolar width was approximately 0.2. This means that 1 mm of expansion is accompanied by 5 degrees of molar lateral tipping. This coefficient is clinically useful for estimating the permissible limit for mandibular expansion.

  19. Burial Ground Expansion Hydrogeologic Characterization

    Energy Technology Data Exchange (ETDEWEB)

    Gaughan , T.F.

    1999-02-26

    Sirrine Environmental Consultants provided technical oversight of the installation of eighteen groundwater monitoring wells and six exploratory borings around the location of the Burial Ground Expansion.

  20. Convergence of generalized eigenfunction expansions

    Directory of Open Access Journals (Sweden)

    Mayumi Sakata

    2007-05-01

    Full Text Available We present a simplified theory of generalized eigenfunction expansions for a commuting family of bounded operators and with finitely many unbounded operators. We also study the convergence of these expansions, giving an abstract type of uniform convergence result, and illustrate the theory by giving two examples: The Fourier transform on Hecke operators, and the Laplacian operators in hyperbolic spaces.

  1. On the Bantu expansion.

    Science.gov (United States)

    Rowold, Daine J; Perez-Benedico, David; Stojkovic, Oliver; Garcia-Bertrand, Ralph; Herrera, Rene J

    2016-11-15

    Here we report the results of fine resolution Y chromosomal analyses (Y-SNP and Y-STR) of 267 Bantu-speaking males from three populations located in the southeast region of Africa. In an effort to determine the relative Y chromosomal affinities of these three genotyped populations, the findings are interpreted in the context of 74 geographically and ethnically targeted African reference populations representing four major ethno-linguistic groups (Afro-Asiatic, Niger Kordofanin, Khoisan and Pygmoid). In this investigation, we detected a general similarity in the Y chromosome lineages among the geographically dispersed Bantu-speaking populations suggesting a shared heritage and the shallow time depth of the Bantu Expansion. Also, micro-variations in the Bantu Y chromosomal composition across the continent highlight location-specific gene flow patterns with non-Bantu-speaking populations (Khoisan, Pygmy, Afro-Asiatic). Our Y chromosomal results also indicate that the three Bantu-speaking Southeast populations genotyped exhibit unique gene flow patterns involving Eurasian populations but fail to reveal a prevailing genetic affinity to East or Central African Bantu-speaking groups. In addition, the Y-SNP data underscores a longitudinal partitioning in sub-Sahara Africa of two R1b1 subgroups, R1b1-P25* (west) and R1b1a2-M269 (east). No evidence was observed linking the B2a haplogroup detected in the genotyped Southeast African Bantu-speaking populations to gene flow from contemporary Khoisan groups. Copyright © 2016 Elsevier B.V. All rights reserved.

  2. TOPICAL REVIEW: Negative thermal expansion

    Science.gov (United States)

    Barrera, G. D.; Bruno, J. A. O.; Barron, T. H. K.; Allan, N. L.

    2005-02-01

    There has been substantial renewed interest in negative thermal expansion following the discovery that cubic ZrW2O8 contracts over a temperature range in excess of 1000 K. Substances of many different kinds show negative thermal expansion, especially at low temperatures. In this article we review the underlying thermodynamics, emphasizing the roles of thermal stress and elasticity. We also discuss vibrational and non-vibrational mechanisms operating on the atomic scale that are responsible for negative expansion, both isotropic and anisotropic, in a wide range of materials.

  3. Thermal Expansion of Polyurethane Foam

    Science.gov (United States)

    Lerch, Bradley A.; Sullivan, Roy M.

    2006-01-01

    Closed cell foams are often used for thermal insulation. In the case of the Space Shuttle, the External Tank uses several thermal protection systems to maintain the temperature of the cryogenic fuels. A few of these systems are polyurethane, closed cell foams. In an attempt to better understand the foam behavior on the tank, we are in the process of developing and improving thermal-mechanical models for the foams. These models will start at the microstructural level and progress to the overall structural behavior of the foams on the tank. One of the key properties for model characterization and verification is thermal expansion. Since the foam is not a material, but a structure, the modeling of the expansion is complex. It is also exacerbated by the anisoptropy of the material. During the spraying and foaming process, the cells become elongated in the rise direction and this imparts different properties in the rise direction than in the transverse directions. Our approach is to treat the foam as a two part structure consisting of the polymeric cell structure and the gas inside the cells. The polymeric skeleton has a thermal expansion of its own which is derived from the basic polymer chemistry. However, a major contributor to the thermal expansion is the volume change associated with the gas inside of the closed cells. As this gas expands it exerts pressure on the cell walls and changes the shape and size of the cells. The amount that this occurs depends on the elastic and viscoplastic properties of the polymer skeleton. The more compliant the polymeric skeleton, the more influence the gas pressure has on the expansion. An additional influence on the expansion process is that the polymeric skeleton begins to breakdown at elevated temperatures and releases additional gas species into the cell interiors, adding to the gas pressure. The fact that this is such a complex process makes thermal expansion ideal for testing the models. This report focuses on the thermal

  4. Strategic Complexity and Global Expansion

    DEFF Research Database (Denmark)

    Oladottir, Asta Dis; Hobdari, Bersant; Papanastassiou, Marina

    2012-01-01

    The purpose of this paper is to analyse the determinants of global expansion strategies of newcomer Multinational Corporations (MNCs) by focusing on Iceland, Israel and Ireland. We argue that newcomer MNCs from small open economies pursue complex global expansion strategies (CGES). We distinguish....... The empirical evidence suggests that newcomer MNCs move away from simplistic dualities in the formulation of their strategic choices towards more complex options as a means of maintaining and enhancing their global competitiveness....

  5. Estimates of expansion time scales

    Science.gov (United States)

    Jones, E. M.

    Monte Carlo simulations of the expansion of a spacefaring civilization show that descendants of that civilization should be found near virtually every useful star in the Galaxy in a time much less than the current age of the Galaxy. Only extreme assumptions about local population growth rates, emigration rates, or ship ranges can slow or halt an expansion. The apparent absence of extraterrestrials from the solar system suggests that no such civilization has arisen in the Galaxy.

  6. Reed's Conjecture on hole expansions

    CERN Document Server

    Fouquet, Jean-Luc

    2012-01-01

    In 1998, Reed conjectured that for any graph $G$, $\\chi(G) \\leq \\lceil \\frac{\\omega(G) + \\Delta(G)+1}{2}\\rceil$, where $\\chi(G)$, $\\omega(G)$, and $\\Delta(G)$ respectively denote the chromatic number, the clique number and the maximum degree of $G$. In this paper, we study this conjecture for some {\\em expansions} of graphs, that is graphs obtained with the well known operation {\\em composition} of graphs. We prove that Reed's Conjecture holds for expansions of bipartite graphs, for expansions of odd holes where the minimum chromatic number of the components is even, when some component of the expansion has chromatic number 1 or when a component induces a bipartite graph. Moreover, Reed's Conjecture holds if all components have the same chromatic number, if the components have chromatic number at most 4 and when the odd hole has length 5. Finally, when $G$ is an odd hole expansion, we prove $\\chi(G)\\leq\\lceil\\frac{\\omega(G)+\\Delta(G)+1}{2}\\rceil+1$.

  7. Low thermal expansion glass ceramics

    CERN Document Server

    1995-01-01

    This book is one of a series reporting on international research and development activities conducted by the Schott group of companies With the series, Schott aims to provide an overview of its activities for scientists, engineers, and managers from all branches of industry worldwide where glasses and glass ceramics are of interest Each volume begins with a chapter providing a general idea of the current problems, results, and trends relating to the subjects treated This volume describes the fundamental principles, the manufacturing process, and applications of low thermal expansion glass ceramics The composition, structure, and stability of polycrystalline materials having a low thermal expansion are described, and it is shown how low thermal expansion glass ceramics can be manufactured from appropriately chosen glass compositions Examples illustrate the formation of this type of glass ceramic by utilizing normal production processes together with controlled crystallization Thus glass ceramics with thermal c...

  8. Low Thermal Expansion Glass Ceramics

    CERN Document Server

    Bach, Hans

    2005-01-01

    This book appears in the authoritative series reporting the international research and development activities conducted by the Schott group of companies. This series provides an overview of Schott's activities for scientists, engineers, and managers from all branches of industry worldwide in which glasses and glass ceramics are of interest. Each volume begins with a chapter providing a general idea of the current problems, results, and trends relating to the subjects treated. This new extended edition describes the fundamental principles, the manufacturing process, and applications of low thermal expansion glass ceramics. The composition, structure, and stability of polycrystalline materials having a low thermal expansion are described, and it is shown how low thermal expansion glass ceramics can be manufactured from appropriately chosen glass compositions. Examples illustrate the formation of this type of glass ceramic by utilizing normal production processes together with controlled crystallization. Thus g...

  9. Thermal Expansion of Hafnium Carbide

    Science.gov (United States)

    Grisaffe, Salvatore J.

    1960-01-01

    Since hafnium carbide (HfC) has a melting point of 7029 deg. F, it may have many high-temperature applications. A literature search uncovered very little information about the properties of HfC, and so a program was initiated at the Lewis Research Center to determine some of the physical properties of this material. This note presents the results of the thermal expansion investigation. The thermal-expansion measurements were made with a Gaertner dilatation interferometer calibrated to an accuracy of +/- 1 deg. F. This device indicates expansion by the movement of fringes produced by the cancellation and reinforcement of fixed wave-length light rays which are reflected from the surfaces of two parallel quartz glass disks. The test specimens which separate these disks are three small cones, each approximately 0.20 in. high.

  10. Repeated expansion in burn sequela.

    Science.gov (United States)

    Pitanguy, Ivo; Gontijo de Amorim, Natale Ferreira; Radwanski, Henrique N; Lintz, José Eduardo

    2002-08-01

    This paper presents a retrospective study of the use of 346 expanders in 132 patients operated at the Ivo Pitanguy Clinic, between the period of 1985 and 2000. The expanders were used in the treatment of burn sequela. In the majority of cases, more than one expander was used at the same time. In 42 patients, repeated tissue expansion was done. The re-expanded flaps demonstrated good distension and viability. With the increase in area at each new expansion, larger volume expanders were employed, achieving an adequate advancement of the flaps to remove the injured tissue. The great advantage of using tissue re-expansion in the burned patient is the reconstruction of extensive areas with the same color and texture of neighboring tissues, without the addition of new scars.

  11. 18 CFR 154.309 - Incremental expansions.

    Science.gov (United States)

    2010-04-01

    ... Changes § 154.309 Incremental expansions. (a) For every expansion for which incremental rates are charged... 18 Conservation of Power and Water Resources 1 2010-04-01 2010-04-01 false Incremental expansions... incremental facilities to be rolled-in to the pipeline's rates. For every expansion that has an at-risk...

  12. Low-thermal expansion infrared glass ceramics

    Science.gov (United States)

    Lam, Philip

    2009-05-01

    L2 Tech, Inc. is in development of an innovative infrared-transparent glass ceramic material with low-thermal expansion (ZrW2O8) which has Negative Thermal Expansion (NTE). The glass phase is the infrared-transparent germanate glass which has positive thermal expansion (PTE). Then glass ceramic material has a balanced thermal expansion of near zero. The crystal structure is cubic and the thermal expansion of the glass ceramic is isotropic or equal in all directions.

  13. Expansive Openness in Teacher Practice

    Science.gov (United States)

    Kimmons, Royce

    2016-01-01

    Background/Context: Previous work on the use of open educational resources in K-12 classrooms has generally focused on issues related to cost. The current study takes a more expansive view of openness that also accounts for adaptation and sharing in authentic classroom contexts. Purpose/Objective/Research Question/Focus of Study The study seeks to…

  14. On Fourier re-expansions

    OpenAIRE

    Liflyand, E.

    2012-01-01

    We study an extension to Fourier transforms of the old problem on absolute convergence of the re-expansion in the sine (cosine) Fourier series of an absolutely convergent cosine (sine) Fourier series. The results are obtained by revealing certain relations between the Fourier transforms and their Hilbert transforms.

  15. On persistently positively expansive maps

    Directory of Open Access Journals (Sweden)

    Alexander Arbieto

    2010-06-01

    Full Text Available In this paper, we prove that any C¹-persistently positively expansive map is expanding. This improves a result due to Sakai (Sakai 2004.Neste artigo, mostramos que todo mapa C¹-persistentemente positivamente expansivo e expansor. Isto melhora um resultado devido a Sakai (Sakai 2004.

  16. The bootstrap and edgeworth expansion

    CERN Document Server

    Hall, Peter

    1992-01-01

    This monograph addresses two quite different topics, in the belief that each can shed light on the other. Firstly, it lays the foundation for a particular view of the bootstrap. Secondly, it gives an account of Edgeworth expansion. Chapter 1 is about the bootstrap, witih almost no mention of Edgeworth expansion; Chapter 2 is about Edgeworth expansion, with scarcely a word about the bootstrap; and Chapters 3 and 4 bring these two themes together, using Edgeworth expansion to explore and develop the properites of the bootstrap. The book is aimed a a graduate level audience who has some exposure to the methods of theoretical statistics. However, technical details are delayed until the last chapter (entitled "Details of Mathematical Rogour"), and so a mathematically able reader without knowledge of the rigorous theory of probability will have no trouble understanding the first four-fifths of the book. The book simultaneously fills two gaps in the literature; it provides a very readable graduate level account of t...

  17. Multiscale expansions in discrete world

    Indian Academy of Sciences (India)

    ... multiscale expansions discretely. The power of this manageable method is confirmed by applying it to two selected nonlinear Schrödinger evolution equations. This approach can also be applied to other nonlinear discrete evolution equations. All the computations have been made with Maple computer packet program.

  18. Large N Expansion. Vector Models

    OpenAIRE

    Nissimov, Emil; Pacheva, Svetlana

    2006-01-01

    Preliminary version of a contribution to the "Quantum Field Theory. Non-Perturbative QFT" topical area of "Modern Encyclopedia of Mathematical Physics" (SELECTA), eds. Aref'eva I, and Sternheimer D, Springer (2007). Consists of two parts - "main article" (Large N Expansion. Vector Models) and a "brief article" (BPHZL Renormalization).

  19. Effective Expansion: Balance between Shrinkage and Hygroscopic Expansion.

    Science.gov (United States)

    Suiter, E A; Watson, L E; Tantbirojn, D; Lou, J S B; Versluis, A

    2016-05-01

    The purpose of this study was to investigate the relationship between hygroscopic expansion and polymerization shrinkage for compensation of polymerization shrinkage stresses in a restored tooth. One resin-modified glass-ionomer (RMGI) (Ketac Nano, 3M ESPE), 2 compomers (Dyract, Dentsply; Compoglass, Ivoclar), and a universal resin-based composite (Esthet•X HD, Dentsply) were tested. Volumetric change after polymerization ("total shrinkage") and during 4 wk of water storage at 37°C was measured using an optical method (n= 10). Post-gel shrinkage was measured during polymerization using a strain gauge method (n= 10). Extracted human molars with large mesio-occluso-distal slot preparations were restored with the tested restorative materials. Tooth surfaces at baseline (preparation), after restoration, and during 4 wk of 37°C water storage were scanned with an optical scanner to determine cuspal flexure (n= 8). Occlusal interface integrity was measured using dye penetration. Data were analyzed using analysis of variance and post hoc tests (significance level 0.05). All tested materials shrunk after polymerization. RMGI had the highest total shrinkage (4.65%) but lowest post-gel shrinkage (0.35%). Shrinkage values dropped significantly during storage in water but had not completely compensated polymerization shrinkage after 4 wk. All restored teeth initially exhibited inward (negative) cuspal flexure due to polymerization shrinkage. Cuspal flexure with the RMGI restoration was significantly less (-6.4 µm) than with the other materials (-12.1 to -14.1 µm). After 1 d, cuspal flexure reversed to +5.0 µm cuspal expansion with the RMGI and increased to +9.3 µm at 4 wk. After 4 wk, hygroscopic expansion compensated cuspal flexure in a compomer (Compoglass) and reduced flexure with Dyract and resin-based composite. Marginal integrity (93.7% intact restoration wall) was best for the Compoglass restorations and lowest (73.1%) for the RMGI restorations. Hygroscopic

  20. Shrub expansion in SW Greenland

    DEFF Research Database (Denmark)

    Jørgensen, Rasmus Halfdan

    , and has a range of ecosystem effects where it occurs. Shrub expansion has to a large extend been attributed to increasing temperatures over the past century, while grazing and human disturbance have received less attention. Alnus viridis ssp. crispa is a common arctic species that contributes...... including only undisturbed sites. Shrub cover increased most on E and SE facing slopes, in sites with stable substrate, in areas characterised by human disturbance and in areas without muskoxen grazing. Aspect and human disturbances had the strongest effect on shrub expansion, followed by muskoxen...... locations. A. viridis represents an interesting case to study these effects. SW Greenland is a subarctic to low-arctic region with only limited increases in temperatures during the past decades, and observed climate trends being largely dependent on the observation period. In this region there is limited...

  1. Shrub expansion in SW Greenland

    DEFF Research Database (Denmark)

    Jørgensen, Rasmus Halfdan

    of firewood collection. A delayed reaction to the ending of the little ice age cannot be excluded, but seems rather unlikely considering other studies from Greenland. Effects of global warming in SW Greenland must be studied over even longer time periods than the 120 years of the current study. To answer......, and has a range of ecosystem effects where it occurs. Shrub expansion has to a large extend been attributed to increasing temperatures over the past century, while grazing and human disturbance have received less attention. Alnus viridis ssp. crispa is a common arctic species that contributes...... by factors like grazing and human disturbance; II. which climatic factors control shrub growth in SW Greenland and whether these have improved sufficiently over the past century to allow shrub expansion; III. whether growth of A. viridis is promoted by experimental warming; IV. and whether plant genotypes...

  2. RELIABILITY OF LENTICULAR EXPANSION COMPENSATORS

    Directory of Open Access Journals (Sweden)

    Gabriel BURLACU,

    2011-11-01

    Full Text Available Axial lenticular compensators are made to take over the longitudinal heat expansion, shock , vibration and noise, made elastic connections for piping systems. In order to have a long life for installations it is necessary that all elements, including lenticular compensators, have a good reliability. This desire can be did by technology of manufactoring and assembly of compensators, the material for lenses and by maintenance.of compensator

  3. Simplifying Bridge Expansion Joint Design and Maintenance

    Science.gov (United States)

    2011-10-19

    This report presents a study focused on identifying the most durable expansion joints for the South : Carolina Department of Transportation. This is performed by proposing a degradation model for the : expansion joints and updating it based on bridge...

  4. 48 CFR 570.403 - Expansion requests.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 4 2010-10-01 2010-10-01 false Expansion requests. 570.403 Section 570.403 Federal Acquisition Regulations System GENERAL SERVICES ADMINISTRATION SPECIAL... Continued Space Requirements 570.403 Expansion requests. (a) If the expansion space is in the general scope...

  5. Expansion of protein domain repeats.

    Directory of Open Access Journals (Sweden)

    Asa K Björklund

    2006-08-01

    Full Text Available Many proteins, especially in eukaryotes, contain tandem repeats of several domains from the same family. These repeats have a variety of binding properties and are involved in protein-protein interactions as well as binding to other ligands such as DNA and RNA. The rapid expansion of protein domain repeats is assumed to have evolved through internal tandem duplications. However, the exact mechanisms behind these tandem duplications are not well-understood. Here, we have studied the evolution, function, protein structure, gene structure, and phylogenetic distribution of domain repeats. For this purpose we have assigned Pfam-A domain families to 24 proteomes with more sensitive domain assignments in the repeat regions. These assignments confirmed previous findings that eukaryotes, and in particular vertebrates, contain a much higher fraction of proteins with repeats compared with prokaryotes. The internal sequence similarity in each protein revealed that the domain repeats are often expanded through duplications of several domains at a time, while the duplication of one domain is less common. Many of the repeats appear to have been duplicated in the middle of the repeat region. This is in strong contrast to the evolution of other proteins that mainly works through additions of single domains at either terminus. Further, we found that some domain families show distinct duplication patterns, e.g., nebulin domains have mainly been expanded with a unit of seven domains at a time, while duplications of other domain families involve varying numbers of domains. Finally, no common mechanism for the expansion of all repeats could be detected. We found that the duplication patterns show no dependence on the size of the domains. Further, repeat expansion in some families can possibly be explained by shuffling of exons. However, exon shuffling could not have created all repeats.

  6. Contribution of thermal expansion and

    Directory of Open Access Journals (Sweden)

    O.I.Pursky

    2007-01-01

    Full Text Available A theoretical model is developed to describe the experimental results obtained for the isobaric thermal conductivity of rare gas solids (RGS. The isobaric thermal conductivity of RGS has been analysed within Debye approximation with regard to the effect of thermal expansion. The suggested model takes into consideration the fact that thermal conductivity is determined by U-processes while above the phonon mobility edge it is determined by "diffusive" modes migrating randomly from site to site. The mobility edge ω0 is determined from the condition that the phonon mean-free path restricted by the U-processes cannot be smaller than half of the phonon wavelength.

  7. Gravitational entropy of cosmic expansion

    CERN Document Server

    Sussman, Roberto A

    2014-01-01

    We apply a recent proposal to define "gravitational entropy" to the expansion of cosmic voids within the framework of non-perturbative General Relativity. By considering CDM void configurations compatible with basic observational constraints, we show that this entropy grows from post-inflationary conditions towards a final asymptotic value in a late time fully non-linear regime described by the Lemaitre-Tolman-Bondi (LTB) dust models. A qualitatively analogous behavior occurs if we assume a positive cosmological constant consistent with a $\\Lambda$-CDM background model. However, the $\\Lambda$ term introduces a significant suppression of entropy growth with the terminal equilibrium value reached at a much faster rate.

  8. Cerrejon expansion in a tight market?

    Energy Technology Data Exchange (ETDEWEB)

    Pretelt, A. [Carbocol SA, Bogota (Colombia)

    1995-12-31

    Examines plans to expand Carbocol`s Cerrejon North Zone coal mine (Colombia). Covers: background; current status of the project; main features of the expansion (i.e. coal reserves, infrastructure, operating costs, expansion schedule and market factors); advantages of expansion; and Carbocol`s vision of the market. A positive decision to expand will depend on the results of a feasibility class III study which will define in exact terms the technical and economic aspects of the expansion and the best way to execute it. The study will be completed next year. The expansion programme should improve the profitability of the project. 10 figs.

  9. Imagination as expansion of experience.

    Science.gov (United States)

    Zittoun, Tania; Cerchia, Frédéric

    2013-09-01

    This paper proposes a developmental view on imagination: from this perspective, imagination can be seen as triggered by some disrupting event, which generates a disjunction from the person's unfolding experience of the "real" world, and as unfolding as a loop, which eventually comes back to the actual experience. Examining recent and classical theorization of imagination in psychology, the paper opposes a deficitary view of imagination to an expansive notion of imagination. The paper explores Piaget, Vygotsky, Harris and Pelaprat & Cole consider: 1) What does provoke a "rupture" or disjunction? 2) What are the psychological processes involved in the imaginary loop? 3) What nourishes such processes? 4) What are the consequences of such imaginary loop, or what does it enable doing? The paper proposes to adopt an expansive view of imagination, as Vygotsky proposed-a perspective that has been under-explored empirically since his seminal work. To stimulate such sociocultural psychology of imagination, two empirical examples are provided, one showing how children make sense of metaphor in an experimental setting, the other showing a young person using a novel met at school as symbolic resource.

  10. Fast algorithms for Quadrature by Expansion I: Globally valid expansions

    Science.gov (United States)

    Rachh, Manas; Klöckner, Andreas; O'Neil, Michael

    2017-09-01

    The use of integral equation methods for the efficient numerical solution of PDE boundary value problems requires two main tools: quadrature rules for the evaluation of layer potential integral operators with singular kernels, and fast algorithms for solving the resulting dense linear systems. Classically, these tools were developed separately. In this work, we present a unified numerical scheme based on coupling Quadrature by Expansion, a recent quadrature method, to a customized Fast Multipole Method (FMM) for the Helmholtz equation in two dimensions. The method allows the evaluation of layer potentials in linear-time complexity, anywhere in space, with a uniform, user-chosen level of accuracy as a black-box computational method. Providing this capability requires geometric and algorithmic considerations beyond the needs of standard FMMs as well as careful consideration of the accuracy of multipole translations. We illustrate the speed and accuracy of our method with various numerical examples.

  11. On the equisummability of Hermite and Fourier expansions

    Indian Academy of Sciences (India)

    We prove an equisummability result for the Fourier expansions and Hermite expansions as well as special Hermite expansions. We also prove the uniform boundedness of the Bochner-Riesz means associated to the Hermite expansions for polyradial functions.

  12. Relationship Development in Greenfield Expansions

    DEFF Research Database (Denmark)

    Drogendijk, Rian; Andersson, Ulf

    2013-01-01

    This paper investigates conceptually how new Greenfield subsidiaries develop relationships over time. We focus our analysis on the earliest start-up stage of new Greenfield subsidiaries, and on the dynamics of relationships development with five different groups of actors within the MNC...... and the local environment of the new Greenfield. We argue that relationship strength, or the intensity of interaction and resource exchange, depends on the new Greenfield''s degree of dependence or interdependence within these relationships and develop propositions based on institutional theory, resource...... dependency theory and network approaches. In the concluding sections we suggest directions for future work to enhance understanding of the dynamics of relationship management in new Greenfield expansions....

  13. Expansion of Physician Assistant Education.

    Science.gov (United States)

    Cawley, James F; Jones, P. Eugene; Miller, Anthony A; Orcutt, Venetia L

    2016-12-01

    Physician assistant (PA) educational programs were created in the 1960s to prepare a new type of health care practitioner. Physician assistant programs began as experiments in medical education, and later, they proved to be highly successful in preparing capable, flexible, and productive clinicians. The growth of PA educational programs in US medical education-stimulated by grants, public policy, and anticipated shortages of providers-has gone through 3 distinct phases. At present, such programs are in the midst of the third growth spurt that is expected to continue beyond 2020, as a large number of colleges and universities seek to sponsor PA programs and attain accreditation status. Characteristics of these new programs are described, and the implications of the current expansion of PA education are examined.

  14. Serial Tissue Expansion at the Same Site in Pediatric Patients: Is the Subsequent Expansion Faster?

    Directory of Open Access Journals (Sweden)

    Moon Ki Lee

    2017-11-01

    Full Text Available Background Serial tissue expansion is performed to remove giant congenital melanocytic nevi. However, there have been no studies comparing the expansion rate between the subsequent and preceding expansions. In this study, we analyzed the rate of expansion in accordance with the number of surgeries, expander location, expander size, and sex. Methods A retrospective analysis was performed in pediatric patients who underwent tissue expansion for giant congenital melanocytic nevi. We tested four factors that may influence the expansion rate: The number of surgeries, expander location, expander size, and sex. The rate of expansion was calculated by dividing the ‘inflation amount’ by the ‘expander size’. Results The expansion rate, compared with the first-time group, was 1.25 times higher in the second-or-more group (P=0.04 and 1.84 times higher in the third-or-more group (P<0.01. The expansion rate was higher at the trunk than at other sites (P<0.01. There was a tendency of lower expansion rate for larger expanders (P=0.03. Sex did not affect the expansion rate. Conclusions There was a positive correlation between the number of surgeries and the expansion rate, a positive correlation between the expander location and the expansion rate, and a negative correlation between the expander size and the expansion rate.

  15. Pressurized electrolysis stack with thermal expansion capability

    Science.gov (United States)

    Bourgeois, Richard Scott

    2015-07-14

    The present techniques provide systems and methods for mounting an electrolyzer stack in an outer shell so as to allow for differential thermal expansion of the electrolyzer stack and shell. Generally, an electrolyzer stack may be formed from a material with a high coefficient of thermal expansion, while the shell may be formed from a material having a lower coefficient of thermal expansion. The differences between the coefficients of thermal expansion may lead to damage to the electrolyzer stack as the shell may restrain the thermal expansion of the electrolyzer stack. To allow for the differences in thermal expansion, the electrolyzer stack may be mounted within the shell leaving a space between the electrolyzer stack and shell. The space between the electrolyzer stack and the shell may be filled with a non-conductive fluid to further equalize pressure inside and outside of the electrolyzer stack.

  16. Fundamentals of Thermal Expansion and Thermal Contraction

    OpenAIRE

    Liu, Zi-Kui; Shang, Shun-Li; Wang, Yi

    2017-01-01

    Thermal expansion is an important property of substances. Its theoretical prediction has been challenging, particularly in cases the volume decreases with temperature, i.e., thermal contraction or negative thermal expansion at high temperatures. In this paper, a new theory recently developed by the authors has been reviewed and further examined in the framework of fundamental thermodynamics and statistical mechanics. Its applications to cerium with colossal thermal expansion and Fe3Pt with th...

  17. Structure and thermal expansion of liquid bismuth

    Directory of Open Access Journals (Sweden)

    Mudry S.

    2015-12-01

    Full Text Available Experimental structural data for liquid Bi were used for estimation of the main structure parameters as well as the thermal expansion coefficient both in supercooled and superheated temperature ranges. It was shown that the equilibrium melt had a positive thermal expansion coefficient within a temperature range upon melting and a negative one at higher temperatures. The former was related to structure changes upon melting, whereas the latter with topologic disordering upon further heating. It was found that the superheated melt had a negative thermal expansion coefficient. The results obtained from structural data were compared with the thermal expansion coefficient calculated from the data of density for liquid Bi.

  18. Thermal expansion of L-ascorbic acid

    Science.gov (United States)

    Nicolaï, B.; Barrio, M.; Tamarit, J.-Ll.; Céolin, R.; Rietveld, I. B.

    2017-04-01

    The specific volume of vitamin C has been investigated by X-ray powder diffraction as a function of temperature from 110 K up to complete degradation around 440 K. Its thermal expansion is relatively small in comparison with other organic compounds with an expansivity α v of 1.2(3) × 10-4 K-1. The structure consists of strongly bound molecules in the ac plane through a dense network of hydrogen bonds. The thermal expansion is anisotropic. Along the b axis, the expansion has most leeway and is about 10 times larger than in the other directions.

  19. Primordial vorticity and gradient expansion

    CERN Document Server

    Giovannini, Massimo

    2012-01-01

    The evolution equations of the vorticities of the electrons, ions and photons in a pre-decoupling plasma are derived, in a fully inhomogeneous geometry, by combining the general relativistic gradient expansion and the drift approximation within the Adler-Misner-Deser decomposition. The vorticity transfer between the different species is discussed in this novel framework and a set of general conservation laws, connecting the vorticities of the three-component plasma with the magnetic field intensity, is derived. After demonstrating that a source of large-scale vorticity resides in the spatial gradients of the geometry and of the electromagnetic sources, the total vorticity is estimated to lowest order in the spatial gradients and by enforcing the validity of the momentum constraint. By acknowledging the current bounds on the tensor to scalar ratio in the (minimal) tensor extension of the $\\Lambda$CDM paradigm the maximal comoving magnetic field induced by the total vorticity turns out to be, at most, of the or...

  20. Local expansions and accretive mappings

    Directory of Open Access Journals (Sweden)

    W. A. Kirk

    1983-01-01

    Full Text Available Let X and Y be complete metric spaces with Y metrically convex, let D⊂X be open, fix u0∈X, and let d(u=d(u0,u for all u∈D. Let f:X→2Y be a closed mapping which maps open subsets of D onto open sets in Y, and suppose f is locally expansive on D in the sense that there exists a continuous nonincreasing function c:R+→R+ with ∫+∞c(sds=+∞ such that each point x∈D has a neighborhood N for which dist(f(u,f(v≥c(max{d(u,d(v}d(u,v for all u,v∈N. Then, given y∈Y, it is shown that y∈f(D iff there exists x0∈D such that for x∈X\\D, dist(y,f(x0≤dist(u,f(x. This result is then applied to the study of existence of zeros of (set-valued locally strongly accretive and ϕ-accretive mappings in Banach spaces

  1. Earnings Returns to the British Education Expansion

    Science.gov (United States)

    Devereux, Paul J.; Fan, Wen

    2011-01-01

    We study the effects of the large expansion in British educational attainment that took place for cohorts born between 1970 and 1975. Using the Quarterly Labour Force Survey, we find that the expansion caused men to increase education by about a year on average and gain about 8% higher wages; women obtained a slightly greater increase in education…

  2. Series expansion of the modified Einstein Procedure

    Science.gov (United States)

    Seema Chandrakant Shah-Fairbank

    2009-01-01

    This study examines calculating total sediment discharge based on the Modified Einstein Procedure (MEP). A new procedure based on the Series Expansion of the Modified Einstein Procedure (SEMEP) has been developed. This procedure contains four main modifications to MEP. First, SEMEP solves the Einstein integrals quickly and accurately based on a series expansion. Next,...

  3. Virial expansion coefficients in the harmonic approximation

    DEFF Research Database (Denmark)

    R. Armstrong, J.; Zinner, Nikolaj Thomas; V. Fedorov, D.

    2012-01-01

    The virial expansion method is applied within a harmonic approximation to an interacting N-body system of identical fermions. We compute the canonical partition functions for two and three particles to get the two lowest orders in the expansion. The energy spectrum is carefully interpolated...

  4. Platform Expansion Design as Strategic Choice

    DEFF Research Database (Denmark)

    Staykova, Kalina S.; Damsgaard, Jan

    2016-01-01

    In this paper, we address how the strategic choice of platform expansion design impacts the subse-quent platform strategy. We identify two distinct approaches to platform expansion – platform bun-dling and platform constellations, which currently co-exist. The purpose of this paper is to outline...

  5. The heavy quark expansion of QCD

    Energy Technology Data Exchange (ETDEWEB)

    Falk, A.F. [Johns Hopkins Univ., Baltimore, MD (United States). Dept. of Physics and Astronomy

    1997-06-01

    These lectures contain an elementary introduction to heavy quark symmetry and the heavy quark expansion. Applications such as the expansion of heavy meson decay constants and the treatment of inclusive and exclusive semileptonic B decays are included. Heavy hadron production via nonperturbative fragmentation processes is also discussed. 54 refs., 7 figs.

  6. Expansion techniques for collisionless stellar dynamical simulations

    Energy Technology Data Exchange (ETDEWEB)

    Meiron, Yohai [Kavli Institute for Astronomy and Astrophysics at Peking University, Beijing 100871 (China); Li, Baile; Holley-Bockelmann, Kelly [Department of Physics and Astronomy, Vanderbilt University, Nashville, TN 37235 (United States); Spurzem, Rainer, E-mail: ymeiron@pku.edu.cn [National Astronomical Observatories of China, Chinese Academy of Sciences, Beijing 100012 (China)

    2014-09-10

    We present graphics processing unit (GPU) implementations of two fast force calculation methods based on series expansions of the Poisson equation. One method is the self-consistent field (SCF) method, which is a Fourier-like expansion of the density field in some basis set; the other method is the multipole expansion (MEX) method, which is a Taylor-like expansion of the Green's function. MEX, which has been advocated in the past, has not gained as much popularity as SCF. Both are particle-field methods and optimized for collisionless galactic dynamics, but while SCF is a 'pure' expansion, MEX is an expansion in just the angular part; thus, MEX is capable of capturing radial structure easily, while SCF needs a large number of radial terms. We show that despite the expansion bias, these methods are more accurate than direct techniques for the same number of particles. The performance of our GPU code, which we call ETICS, is profiled and compared to a CPU implementation. On the tested GPU hardware, a full force calculation for one million particles took ∼0.1 s (depending on expansion cutoff), making simulations with as many as 10{sup 8} particles fast for a comparatively small number of nodes.

  7. Business information query expansion through semantic network

    Science.gov (United States)

    Gong, Zhiguo; Muyeba, Maybin; Guo, Jingzhi

    2010-02-01

    In this article, we propose a method for business information query expansions. In our approach, hypernym/hyponymy and synonym relations in WordNet are used as the basic expansion rules. Then we use WordNet Lexical Chains and WordNet semantic similarity to assign terms in the same query into different groups with respect to their semantic similarities. For each group, we expand the highest terms in the WordNet hierarchies with hypernym and synonym, the lowest terms with hyponym and synonym and all other terms with only synonym. In this way, the contradictory caused by full expansion can be well controlled. Furthermore, we use collection-related term semantic network to further improve the expansion performance. And our experiment reveals that our solution for query expansion can improve the query performance dramatically.

  8. Maxwell superalgebras and Abelian semigroup expansion

    Directory of Open Access Journals (Sweden)

    P.K. Concha

    2014-09-01

    Full Text Available The Abelian semigroup expansion is a powerful and simple method to derive new Lie algebras from a given one. Recently it was shown that the S-expansion of so(3,2 leads us to the Maxwell algebra M. In this paper we extend this result to superalgebras, by proving that different choices of abelian semigroups S lead to interesting D=4 Maxwell Superalgebras. In particular, the minimal Maxwell superalgebra sM and the N-extended Maxwell superalgebra sM(N recently found by the Maurer–Cartan expansion procedure, are derived alternatively as an S-expansion of osp(4|N. Moreover, we show that new minimal Maxwell superalgebras type sMm+2 and their N-extended generalization can be obtained using the S-expansion procedure.

  9. Giant negative thermal expansion in magnetic nanocrystals

    Science.gov (United States)

    Zheng, X. G.; Kubozono, H.; Yamada, H.; Kato, K.; Ishiwata, Y.; Xu, C. N.

    2008-12-01

    Most solids expand when they are heated, but a property known as negative thermal expansion has been observed in a number of materials, including the oxide ZrW2O8 (ref. 1) and the framework material ZnxCd1-x(CN)2 (refs 2,3). This unusual behaviour can be understood in terms of low-energy phonons, while the colossal values of both positive and negative thermal expansion recently observed in another framework material, Ag3[Co(CN)6], have been explained in terms of the geometric flexibility of its metal-cyanide-metal linkages. Thermal expansion can also be stopped in some magnetic transition metal alloys below their magnetic ordering temperature, a phenomenon known as the Invar effect, and the possibility of exploiting materials with tuneable positive or negative thermal expansion in industrial applications has led to intense interest in both the Invar effect and negative thermal expansion. Here we report the results of thermal expansion experiments on three magnetic nanocrystals-CuO, MnF2 and NiO-and find evidence for negative thermal expansion in both CuO and MnF2 below their magnetic ordering temperatures, but not in NiO. Larger particles of CuO and MnF2 also show prominent magnetostriction (that is, they change shape in response to an applied magnetic field), which results in significantly reduced thermal expansion below their magnetic ordering temperatures; this behaviour is not observed in NiO. We propose that the negative thermal expansion effect in CuO (which is four times larger than that observed in ZrW2O8) and MnF2 is a general property of nanoparticles in which there is strong coupling between magnetism and the crystal lattice.

  10. On the equisummability of Hermite and Fourier expansions

    Indian Academy of Sciences (India)

    We prove an equisummability result for the Fourier expansions and. Hermite expansions as well as special Hermite expansions. We also prove the uniform boundedness of the Bochner-Riesz means associated to the Hermite expansions for polyradial functions. Keywords. Hermite functions; special Hermite expansions; ...

  11. Expansion Coefficient on Oxides and Oxide Ceramics.

    Science.gov (United States)

    1986-05-01

    Classification) EXPANSION COEFFICIENTS ON OXIDES AND OXIDE CERAMICS 12 PFRSONAL AUTHOR(S) Josephine Covino 13a TYPE OF REPORT 13b TIME COVERED 114 DATE OF REPORT...drastically alter expansion properties of oxides. It has been found that fine-grained (᝺ tm) anisotropic ceramic materials, such as hafnium oxide, hafnium ...Gokhale. "Thermal Expansion of Zircon ," Jap. J. AppZ. Phys., 7 (1968), p. 1126. 34 -- ’-a.’! nw-W’W L. .WW U. .PV _ 77 NWC TP 6663 81. J. L. Amoros, M

  12. Some Improved Nonperturbative Bounds for Fermionic Expansions

    Energy Technology Data Exchange (ETDEWEB)

    Lohmann, Martin, E-mail: marlohmann@gmail.com [Universita di Roma Tre, Dipartimento di Matematica (Italy)

    2016-06-15

    We reconsider the Gram-Hadamard bound as it is used in constructive quantum field theory and many body physics to prove convergence of Fermionic perturbative expansions. Our approach uses a recursion for the amplitudes of the expansion, discovered in a model problem by Djokic (2013). It explains the standard way to bound the expansion from a new point of view, and for some of the amplitudes provides new bounds, which avoid the use of Fourier transform, and are therefore superior to the standard bounds for models like the cold interacting Fermi gas.

  13. Thermal expansion: Metallic elements and alloys. [Handbook

    Science.gov (United States)

    Touloukian, Y. S.; Kirby, R. K.; Taylor, R. E.; Desai, P. D.

    1975-01-01

    The introductory sections of the work are devoted to the theory of thermal expansion of solids and to methods for the measurement of the linear thermal expansion of solids (X-ray methods, high speed methods, interferometry, push-rod dilatometry, etc.). The bulk of the work is devoted to numerical data on the thermal linear expansion of all the metallic elements, a large number of intermetallics, and a large number of binary alloy systems and multiple alloy systems. A comprehensive bibliography is provided along with an index to the materials examined.

  14. Collisional and collisionless expansion of Yukawa balls.

    Science.gov (United States)

    Piel, Alexander; Goree, John A

    2013-12-01

    The expansion of Yukawa balls is studied by means of molecular dynamics simulations of collisionless and collisional situations. High computation speed was achieved by using the parallel computing power of graphics processing units. When the radius of the Yukawa ball is large compared to the shielding length, the expansion process starts with the blow-off of the outermost layer. A rarefactive wave subsequently propagates radially inward at the speed of longitudinal phonons. This mechanism is fundamentally different from Coulomb explosions, which employ a self-similar expansion of the entire system. In the collisionless limit, the outer layers carry away most of the available energy. The simulations are compared with analytical estimates. In the collisional case, the expansion process can be described by a nonlinear diffusion equation that is a special case of the porous medium equation.

  15. Thermal expansion of doped lanthanum gallates

    Indian Academy of Sciences (India)

    Thermal expansion of several compositions of Sr and Mg-doped LaGaO3 including an -site deficient composition (La0.9Sr0.1)0.98(Ga0.8Mg0.2)O2.821 were measured in the temperature range from 298 to 1273 K. The effect of doping on thermal expansion was studied by varying the composition at one site of the ...

  16. Expansion and rupture of charged microcapsules

    OpenAIRE

    Datta, Sujit S.; Abbaspourrad, Alireza; Weitz, David A

    2014-01-01

    We study the deformations of pH-responsive spherical microcapsules -- micrometer-scale liquid drops surrounded by thin, solid shells -- under the influence of electrostatic forces. When exposed to a large concentration of NaOH, the microcapsules become highly charged, and expand isotropically. We find that the extent of this expansion can be understood by coupling electrostatics with shell theory; moreover, the expansion dynamics is well described by Darcy's law for fluid flow through the mic...

  17. Tissue expansion: Concepts, techniques and unfavourable results

    OpenAIRE

    Milind S Wagh; Varun Dixit

    2013-01-01

    The phenomenon of tissue expansion is observed in nature all the time. The same properties of the human skin to stretch and expand and yield extra skin if placed under continuous stress over a prolonged period of time has been utilised for reconstructive purposes with the help of a silicon balloon inserted under the skin and progressively filled with saline. The technique of tissue expansion is now more than three decades old and has been a value addition to our armamentarium in reconstructiv...

  18. Negative thermal expansion in framework compounds

    Indian Academy of Sciences (India)

    2015-11-27

    Nov 27, 2015 ... We have studied negative thermal expansion (NTE) compounds with chemi- cal compositions of NX2O8 and NX2O7 (N=Zr, Hf and X=W, Mo, V) and M2O (M=Cu, Ag) using the techniques of inelastic neutron scattering and lattice dynamics. There is a large variation in the negative thermal expansion ...

  19. Russia and the Future Expansion of NATO

    Science.gov (United States)

    2011-03-24

    2001 that he did not intend to let enlargement undermine the potential for U.S.- Russia cooperation. Later in the summer, Putin took a further step...St ra te gy R es ea rc h Pr oj ec t RUSSIA AND THE FUTURE EXPANSION OF NATO BY COLONEL RADEK CERNY Czech Army DISTRIBUTION STATEMENT A...Strategy Research Project 3. DATES COVERED (From - To) 4. TITLE AND SUBTITLE Russia and the Future Expansion of NATO 5a. CONTRACT

  20. The. delta. expansion and local gauge invariance

    Energy Technology Data Exchange (ETDEWEB)

    Bender, C.M. (Department of Physics, Washington University, St. Louis, Missouri 63130 (US)); Cooper, F. (Department of Physics, Brown University, Providence, Rhode Island 02912 Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexic o 87545); Milton, K.A. (Department of Physics, The Ohio State University, Columbus, Ohio 43210 Department of Physics and Astronomy, University of Oklahoma, Norman, Oklaho ma 73019)

    1989-08-15

    A recently proposed approximation method, called the {delta} expansion, was introduced in the context of a self-interacting scalar field theory. This approximation method offers the hope of obtaining nonperturbative information about a quantum field theory using perturbative techniques. In this paper we extend formally the {delta}-expansion methods to field theories having local gauge symmetry. We then compute the anomaly in the Schwinger model.

  1. Stochastic quantization and 1/N expansion

    Energy Technology Data Exchange (ETDEWEB)

    Brunelli, J.C. [Instituto de Fisica Teorica (IFT), Sao Paulo, SP (Brazil); Mendes, R.S. [Sao Paulo Univ., SP (Brazil). Inst. de Fisica

    1992-10-01

    We study the 1/N expansion of field theories in the stochastic quantization method of Parisi and Wu using the supersymmetric functional approach. This formulation provides a systematic procedure to implement the 1/N expansion which resembles the ones used in the equilibrium. The 1/N perturbation theory for the non linear sigma model in two dimensions is worked out as an example. (author). 19 refs., 5 figs.

  2. Fixed Point Theorems for Times Reasonable Expansive Mapping

    Directory of Open Access Journals (Sweden)

    Chen Chunfang

    2008-01-01

    Full Text Available Abstract Based on previous notions of expansive mapping, times reasonable expansive mapping is defined. The existence of fixed point for times reasonable expansive mapping is discussed and some new results are obtained.

  3. Expansive Soil Crack Depth under Cumulative Damage

    Directory of Open Access Journals (Sweden)

    Bei-xiao Shi

    2014-01-01

    Full Text Available The crack developing depth is a key problem to slope stability of the expansive soil and its project governance and the crack appears under the roles of dry-wet cycle and gradually develops. It is believed from the analysis that, because of its own cohesion, the expansive soil will have a certain amount of deformation under pulling stress but without cracks. The soil body will crack only when the deformation exceeds the ultimate tensile strain that causes cracks. And it is also believed that, due to the combined effect of various environmental factors, particularly changes of the internal water content, the inherent basic physical properties of expansive soil are weakened, and irreversible cumulative damages are eventually formed, resulting in the development of expansive soil cracks in depth. Starting from the perspective of volumetric strain that is caused by water loss, considering the influences of water loss rate and dry-wet cycle on crack developing depth, the crack developing depth calculation model which considers the water loss rate and the cumulative damages is established. Both the proposal of water loss rate and the application of cumulative damage theory to the expansive soil crack development problems try to avoid difficulties in matrix suction measurement, which will surely play a good role in promoting and improving the research of unsaturated expansive soil.

  4. Negative thermal expansion materials: technological key for control of thermal expansion

    Directory of Open Access Journals (Sweden)

    Koshi Takenaka

    2012-01-01

    Full Text Available Most materials expand upon heating. However, although rare, some materials contract upon heating. Such negative thermal expansion (NTE materials have enormous industrial merit because they can control the thermal expansion of materials. Recent progress in materials research enables us to obtain materials exhibiting negative coefficients of linear thermal expansion over −30 ppm K−1. Such giant NTE is opening a new phase of control of thermal expansion in composites. Specifically examining practical aspects, this review briefly summarizes materials and mechanisms of NTE as well as composites containing NTE materials, based mainly on activities of the last decade.

  5. Mapping Brazilian Cropland Expansion, 2000-2013

    Science.gov (United States)

    Zalles, V.; Hansen, M.; Potapov, P.

    2016-12-01

    Brazil is one of the world's leading producers and exporters of agricultural goods. Despite undergoing significant increases in its cropland area in the last decades, it remains one of the countries with the most potential for further agricultural expansion. Most notably, the expansion in production areas of commodity crops such as soybean, corn, and sugarcane has become the leading cause of land cover conversion in Brazil. Natural land covers, such as the Amazon and Cerrado forests, have been negatively affected by this agricultural expansion, causing carbon emissions, biodiversity loss, altered water cycles, and many other disturbances to ecosystem services. Monitoring of change in cropland area extent can provide relevant information to decision makers seeking to understand and manage land cover change drivers and their impacts. In this study, the freely-available Landsat archive was leveraged to produce a large-scale, methodologically consistent map of cropland cover at 30 m. resolution for the entire Brazilian territory in the year 2000. Additionally, we mapped cropland expansion from 2000 to 2013, and used statistical sampling techniques to accurately estimate cropland area per Brazilian state. Using the Global Forest Change product produced by Hansen et al. (2013), we can disaggregate forest cover loss due to cropland expansion by year, revealing spatiotemporal trends that could advance our understanding of the drivers of forest loss.

  6. Supercritical flow characteristics at abrupt expansion structure

    Science.gov (United States)

    Lim, Jia Jun; Puay, How Tion; Zakaria, Nor Azazi

    2017-10-01

    When dealing with the design of a hydraulic structure, lateral expansion is often necessary for flow emerging at high velocity served as a cross-sectional transition. If the abrupt expansion structure is made to diverge rapidly, it will cause the major part of the flow fail to follow the boundaries. If the transition is too gradual, it will result in a waste of structural material. A preliminary study on the flow structure near the expansion and its relationship with flow parameter is carried out in this study. A two-dimensional depth-averaged model is developed to simulate the supercritical flow at the abrupt expansion structure. Constrained Interpolation Profile (CIP) scheme (which is of third order accuracy) is adopted in the numerical model. Results show that the flow structure and flow characteristics at the abrupt expansion can be reproduced numerically. The validation of numerical result is done against analytical studies. The result from numerical simulation showed good agreement with the analytical solution.

  7. Ultra-low thermal expansion realized in giant negative thermal expansion materials through self-compensation

    Science.gov (United States)

    Shen, Fei-Ran; Kuang, Hao; Hu, Feng-Xia; Wu, Hui; Huang, Qing-Zhen; Liang, Fei-Xiang; Qiao, Kai-Ming; Li, Jia; Wang, Jing; Liu, Yao; Zhang, Lei; He, Min; Zhang, Ying; Zuo, Wen-Liang; Sun, Ji-Rong; Shen, Bao-Gen

    2017-10-01

    Materials with zero thermal expansion (ZTE) or precisely tailored thermal expansion are in urgent demand of modern industries. However, the overwhelming majority of materials show positive thermal expansion. To develop ZTE or negative thermal expansion (NTE) materials as compensators has become an important challenge. Here, we present the evidence for the realization of ultra-low thermal expansion in Mn-Co-Ge-In particles. The bulk with the Ni2In-type hexagonal structure undergoes giant NTE owing to a martensitic magnetostructural transition. The major finding is that the thermal expansion behavior can be totally controlled by modulating the crystallinity degree and phase transition from atomic scale. Self-compensation effect leads to ultra-low thermal expansion with a linear expansion coefficient as small as +0.68 × 10-6/K over a wide temperature range around room temperature. The present study opens an avenue to reach ZTE particularly from the large class of giant NTE materials based on phase transition.

  8. Expansions and Extensions : Ergodic, combinatorial and geometric properties of β-expansions with arbitrary digits

    NARCIS (Netherlands)

    Kalle, C.C.C.J.

    2009-01-01

    Let beta be a real number bigger than 1 and A a finite set of arbitrary real numbers. A beta-expansion with digits in A of a real number x is an expression for x by an infinite sum of fractions with powers of beta in the denominators and elements from A in the numerators. Such expansions can be

  9. [Forum on tissue expansion. Expansion of the scalp. Surgical techniques and clinical applications].

    Science.gov (United States)

    Foyatier, J L; Delay, E; Comparin, J P; Latarjet, J; Masson, C L

    1993-02-01

    Repair of all forms of alopecia is one of the principal applications of scalp expansion. The authors have inserted 400 expansion prostheses, including 20 in the scalp. The surgical technique, choice of material and various types of flaps are described and illustrated by clinical cases of extensive alopecia.

  10. Anisotropic thermal expansion in flexible materials

    Science.gov (United States)

    Romao, Carl P.

    2017-10-01

    A definition of the Grüneisen parameters for anisotropic materials is derived based on the response of phonon frequencies to uniaxial stress perturbations. This Grüneisen model relates the thermal expansion in a given direction (αi i) to one element of the elastic compliance tensor, which corresponds to the Young's modulus in that direction (Yi i). The model is tested through ab initio prediction of thermal expansion in zinc, graphite, and calcite using density functional perturbation theory, indicating that it could lead to increased accuracy for structurally complex systems. The direct dependence of αi i on Yi i suggests that materials which are flexible along their principal axes but rigid in other directions will generally display both positive and negative thermal expansion.

  11. Extrudate Expansion Modelling through Dimensional Analysis Method

    DEFF Research Database (Denmark)

    A new model framework is proposed to correlate extrudate expansion and extrusion operation parameters for a food extrusion cooking process through dimensional analysis principle, i.e. Buckingham pi theorem. Three dimensionless groups, i.e. energy, water content and temperature, are suggested...... to describe the extrudates expansion. From the three dimensionless groups, an equation with three experimentally determined parameters is derived to express the extrudate expansion. The model is evaluated with whole wheat flour and aquatic feed extrusion experimental data. The average deviations...... of the correlation are respectively 5.9% and 9% for the whole wheat flour and the aquatic feed extrusion. An alternative 4-coefficient equation is also suggested from the 3 dimensionless groups. The average deviations of the alternative equation are respectively 5.8% and 2.5% in correlation with the same set...

  12. Rapid palatal expansion: the role of microcirculation.

    Science.gov (United States)

    Bilello, G; Currò, G; Messina, P; Scardina, G

    2015-08-01

    Transverse palate modifications fall under expansive orthopedic therapy of the upper maxilla. The only practical approach to the problem on the transverse plane is that of performing the expansion of the maxillary arch through an opening of the median palatal suture. It is important to understand the changes of the vascular network in midpalatal suture following the starting of rapid maxillary expansion. It is critical to maintain the blood supply and circulation for the osteogenesis and bone remodeling after the expansion. The aim of this research was to evaluate the effects of rapid orthopedic expansion (REP) at the microcirculatory level through capillaroscopic examination. Fifteen patients in their developing years between 9 and 15 years of age (average age 12.16 years) were examined. The application of the REP was the first step in the planning of orthopedic-orthodontic treatment which foresaw further stages in the odonto-osseous movement. The method of Biomicroscopic Video-Imaging of the microcirculation of oral mucosa is performed through the technique of computerized capillaroscopy and the related software. From the results it is evident that immediately after achieving the expansion of the upper maxilla (t1), a slight decrease in the number of vessels per mm² can be observed. In addition, a slight ectasia can be observed in these vessels in comparison to t0. Comparing the videocapillaroscopic images of t1 and t2, an increase in the capillaries per mm² can be observed. Ectasia of the capillaries, though subject to strictly individual variables, can be considered perfectly normal and it is compatible with the normal biology and physiology of vessel microcirculation.

  13. Longitudinal expansion of field line dipolarization

    Science.gov (United States)

    Saka, O.; Hayashi, K.

    2017-11-01

    We examine the substorm expansions that started at 1155 UT 10 August 1994 in the midnight sector focusing on the longitudinal (eastward) expansion of field line dipolarization in the auroral zone. Eastward expansion of the dipolarization region was observed in all of the H, D, and Z components. The dipolarization that started at 1155 UT (0027 MLT) from 260° of geomagnetic longitude (CMO) expanded to 351°(PBQ) in about 48 min. The expansion velocity was 0.03-0.04°/s, or 1.9 km/s at 62°N of geomagnetic latitude. The dipolarization region expanding to the east was accompanied by a bipolar event at the leading edge of the expansion in latitudes equatorward of the westward electrojet (WEJ). In the midnight sector at the onset meridian, the Magnetospheric Plasma Analyzer (MAP) on board geosynchronous satellite L9 measured electrons and ions between 10 eV and 40 keV. We conclude from the satellite observations that this dipolarization was characterized by the evolution of temperature anisotropies, an increase of the electron and ion temperatures, and a rapid change in the symmetry axis of the temperature tensor. The field line dipolarization and its longitudinal expansion were interpreted in terms of the slow MHD mode triggered by the current disruption. We propose a new magnetosphere-ionosphere coupling (MI-coupling) mechanism based on the scenario that transmitted westward electric fields from the magnetosphere in association with expanding dipolarization produced electrostatic potential (negative) in the ionosphere through differences in the mobility of collisional ions and collisionless electrons. The field-aligned currents that emerged from the negative potential region are arranged in a concentric pattern around the negative potential region, upward toward the center and downward on the peripheral.

  14. Parabolic cyclinder functions : examples of error bounds for asymptotic expansions

    NARCIS (Netherlands)

    R. Vidunas; N.M. Temme (Nico)

    2002-01-01

    textabstractSeveral asymptotic expansions of parabolic cylinder functions are discussedand error bounds for remainders in the expansions are presented. Inparticular Poincaré-type expansions for large values of the argument$z$ and uniform expansions for large values of the parameter areconsidered.

  15. Soft Manifold Dynamics behind Negative Thermal Expansion

    Science.gov (United States)

    Schlesinger, Z.; Rosen, J. A.; Hancock, J. N.; Ramirez, A. P.

    2008-07-01

    Minimal models are developed to examine the origin of large negative thermal expansion in underconstrained systems. The dynamics of these models reveals how underconstraint can organize a thermodynamically extensive manifold of low-energy modes which not only drives negative thermal expansion but extends across the Brillioun zone. Mixing of twist and translation in the eigenvectors of these modes, for which in ZrW2O8 there is evidence from infrared and neutron scattering measurements, emerges naturally in our model as a signature of the dynamics of underconstraint.

  16. Air expansion in the water rocket

    CERN Document Server

    Romanelli, Alejandro; Madina, Federico González

    2012-01-01

    We study the thermodynamics of the water rocket in the thrust phase, taking into account the expansion of the air with water vapor, vapor condensation and the energy taken from the environment. We set up a simple experimental device with a stationary bottle and verified that the gas expansion in the bottle is well approximated by a polytropic process $PV^\\beta$= constant, where the parameter $\\beta$ depends on the initial conditions. We find an analytical expression for $\\beta $ that only depends on the thermodynamic initial conditions and is in good agreement with the experimental results.

  17. NATO Expansion and Alternative Future Security Alignments,

    Science.gov (United States)

    1995-04-01

    International Security," a joint paper by the Institute for USA and Canada and the Center for Naval Analysis, June 1992. 11. Malcolm Mackintosh , "Reform in the...former Under Secretary of Defense for Policy Fred C. Ikle, who opposes NATO expansion, has observed that "This remedy may seem all the more urgent as...opposition to NATO expansion include Fred C. Ikl6, former Under Secretary of Defense for Policy Charles Kupchan, a former member of the U.S. National

  18. Large J expansion in ABJM theory revisited.

    Science.gov (United States)

    Dimov, H; Mladenov, S; Rashkov, R C

    Recently there has been progress in the computation of the anomalous dimensions of gauge theory operators at strong coupling by making use of the AdS/CFT correspondence. On the string theory side they are given by dispersion relations in the semiclassical regime. We revisit the problem of a large-charge expansion of the dispersion relations for simple semiclassical strings in an [Formula: see text] background. We present the calculation of the corresponding anomalous dimensions of the gauge theory operators to an arbitrary order using three different methods. Although the results of the three methods look different, power series expansions show their consistency.

  19. The Monetary Policy – Restrictive or Expansive?

    Directory of Open Access Journals (Sweden)

    Adam Szafarczyk

    2007-12-01

    Full Text Available The monetary policy plays an important role in macroeconomic policy of government. There is a question concerning type of this policy ñ expansive or restrictive (easy or tidy monetary policy. Unfortunately, we have a lot of criteria. Each of them gives us other answer. So due to equitation of Irving Fisher we have dominantly expansive monetary policy. This same situation exists when we use nominal value of rediscount interest rate of central bank. Opposite result appears when we use real value of this interest rate or level of obligatory reserve. Taking under consideration liquidity on money market we know, that level of interest rate is too high.  

  20. Scenarios of Expansion to Electric Generation Capacity

    Directory of Open Access Journals (Sweden)

    José Somoza-Cabrera

    2017-06-01

    Full Text Available We show the building scenarios of expansion to electric generation capacity enough to supply the demand to 2050. We were using the LEAP facility (Long-range Energy Alternatives Planning System, to simulate dispatch of electricity at minimum cost. Finally, we show the cost-benefice analysis of the technologies availability, included externality and CO2 emission limited. However that we included the externals cost in this analysis, it results insufficient to closed gap between fossil and renewable technologies of electric generation. Nevertheless, in some opportunities the renewable options had very important participations in the minimal cost scenario of expansion.

  1. Expansion of the whole wheat flour extrusion

    DEFF Research Database (Denmark)

    Cheng, Hongyuan; Friis, Alan

    2008-01-01

    A new model framework is proposed to describe the expansion of extrudates with extruder operating conditions based on dimensional analysis principle. The Buckingham pi dimensional analysis method is applied to form the basic structure of the model from extrusion process operational parameters. Us....... Using the Central Composite Design (CCD) method, whole wheat flour was processed in a twin-screw extruder with 16 trials. The proposed model can well correlate the expansion of the 16 trials using 3 regression parameters. The average deviation of the correlation is 5.9%....

  2. Cluster expansions for the correlated basis functions theory

    Energy Technology Data Exchange (ETDEWEB)

    Guardiola, R. (Granada Univ. (Spain). Dept. de Fisica Nuclear)

    1982-08-16

    Four kinds of cluster expansions for the calculation of non-diagonal matrix elements of the hamiltonian between correlated states have been derived. The derivation is based on a linearization mechanism for the standard cluster expansions in a configuration mixed state. Particulary simple formulae result for the multiplicative Factor-Aviles-Hartog-Tolhoek expansion and for the exponential form of the Gaudin-Gillespie-Ripka cluster expansion. The resulting expansions are directly usable in finite nuclei.

  3. On Learning Ring-Sum-Expansions

    DEFF Research Database (Denmark)

    Fischer, Paul; Simon, H. -U.

    1992-01-01

    The problem of learning ring-sum-expansions from examples is studied. Ring-sum-expansions (RSE) are representations of Boolean functions over the base {#123;small infinum, (+), 1}#125;, which reflect arithmetic operations in GF(2). k-RSE is the class of ring-sum-expansions containing only monomials...... of length at most k:. term-RSE is the class of ring-sum-expansions having at most I: monomials. It is shown that k-RSE, k>or=1, is learnable while k-term-RSE, k>2, is not learnable if RPnot=NP. Without using a complexity-theoretical hypothesis, it is proven that k-RSE, k>or=1, and k-term-RSE, k>or=2 cannot...... be learned from positive (negative) examples alone. However, if the restriction that the hypothesis which is output by the learning algorithm is also a k-RSE is suspended, then k-RSE is learnable from positive (negative) examples only. Moreover, it is proved that 2-term-RSE is learnable by a conjunction...

  4. Negative thermal expansion in framework compounds

    Indian Academy of Sciences (India)

    electron microscopy, EXAFS and differential scanning calorimetry have been used to study structural properties as a function of temperature for these compounds. In this paper we report the results obtained from our study [14–20] of negative thermal expansion (NTE) compounds with chemical compositions of NX2O8 and.

  5. Polytope expansion of Lie characters and applications

    Energy Technology Data Exchange (ETDEWEB)

    Walton, Mark A., E-mail: walton@uleth.ca [Department of Physics and Astronomy, University of Lethbridge, Lethbridge, Alberta T1K 3M4 (Canada)

    2013-12-15

    The weight systems of finite-dimensional representations of complex, simple Lie algebras exhibit patterns beyond Weyl-group symmetry. These patterns occur because weight systems can be decomposed into lattice polytopes in a natural way. Since lattice polytopes are relatively simple, this decomposition is useful, in addition to being more economical than the decomposition into single weights. An expansion of characters into polytope sums follows from the polytope decomposition of weight systems. We study this polytope expansion here. A new, general formula is given for the polytope sums involved. The combinatorics of the polytope expansion are analyzed; we point out that they are reduced from those of the Weyl character formula (described by the Kostant partition function) in an optimal way. We also show that the weight multiplicities can be found easily from the polytope multiplicities, indicating explicitly the equivalence of the two descriptions. Finally, we demonstrate the utility of the polytope expansion by showing how polytope multiplicities can be used in the calculation of tensor product decompositions, and subalgebra branching rules.

  6. Resonant state expansion of the resolvent

    Energy Technology Data Exchange (ETDEWEB)

    Berggren, T.; Lind, P. (Department of Mathematical Physics, Lund Institute of Technology, P.O. Box 118, S-22100 Lund (Sweden))

    1993-02-01

    An analytic method of generating resonant state expansions from the standard completeness relation of nonrelativistic quantum mechanics is described and shown to reproduce the generalized completeness relations, earlier derived, involving resonant states. The method is then applied to the expansion of the resolvent (the complete Green's function), the symmetry properties of which [ital seem] to be destroyed if a conventional application of the completeness relations is made. These forms of expansions have a continuum term which contains symmetry-restoring contributions and can therefore never vanish identically, nor can it be neglected. The symmetry-conserving form of the expansion has a set of discrete terms which are identical in form to those of the Mittag-Leffler series for the resolvent. In addition, it contains a continuum contribution which in some cases vanishes identically, but in general does not. We illustrate these findings with numerical applictions in which the potential (a square well) is chosen so as to permit analytic evaluation of practically all functions and quantities involved.

  7. Annual cropped area expansion and agricultural production ...

    African Journals Online (AJOL)

    This paper assesses the relationship between annual cropped area expansion and crop output and discusses the implication of such a relationship for environmental management in Benue State, Nigeria. The study was carried out using agricultural production survey (APS) data of five selected crops, namely: rice, sorghum, ...

  8. Hole expansion test of third generation steels

    Science.gov (United States)

    Agirre, Julen; Mendiguren, Joseba; Galdos, Lander; de Argandoña, Eneko Sáenz

    2017-10-01

    The trend towards the implementation of new materials in the chassis of the automobiles is considerably making more complex the manufacturing of the components that built it up. In this scenario materials with higher strengths and lower formabilities are daily faced by tool makers and component producers what reduces the process windows and makes the forming processes to be in the limits of the materials. One of the concerns that tool makers must face during the definition of the tools is the expansion ratios that the holes in the sheet may reach before producing a breakage due to the stretching of the material (also known as edge cracks). For the characterization of such limits, a standard test, the hole expansion test, can be applied so that the limits of the material are known. At the present study, hole expansion tests of a third generation steel, Fortiform1050 with a thickness of 1.2 millimeters have been carried out and compared them to a mild steel, DX54D with a thickness of 0.6 millimeters. A comparison for each material in terms of technology used to punch the hole, mechanical punching vs laser cutting has also been conducted. In addition, the measurement technique (online measurement vs offline measurement) followed in the Hole Expansion Ratio (HER) identification has also been analyzed. Finally, differences between both materials and techniques are presented.

  9. The Asymptotic Expansion Method via Symbolic Computation

    Directory of Open Access Journals (Sweden)

    Juan F. Navarro

    2012-01-01

    Full Text Available This paper describes an algorithm for implementing a perturbation method based on an asymptotic expansion of the solution to a second-order differential equation. We also introduce a new symbolic computation system which works with the so-called modified quasipolynomials, as well as an implementation of the algorithm on it.

  10. Hydrodynamic Gradient Expansion in Gauge Theory Plasmas,

    NARCIS (Netherlands)

    Heller, M.P.; Janik, R.A.; Witaszczyk, P

    2013-01-01

    We utilize the fluid-gravity duality to investigate the large order behavior of hydrodynamic gradient expansion of the dynamics of a gauge theory plasma system. This corresponds to the inclusion of dissipative terms and transport coefficients of very high order. Using the dual gravity description,

  11. Expansion and contraction of finite states

    NARCIS (Netherlands)

    Tamminga, Allard

    2004-01-01

    We present a theory that copes with the dynamics of inconsistent information. A method is set forth to represent possibly inconsistent information by a *finite state*. Next, finite operations for expansion and contraction of finite states are given. No extra-logical element -- a choice function or

  12. A Computational Approach to Competitive Range Expansions

    Science.gov (United States)

    Weber, Markus F.; Poxleitner, Gabriele; Hebisch, Elke; Frey, Erwin; Opitz, Madeleine

    2014-03-01

    Bacterial communities represent complex and dynamic ecological systems. Environmental conditions and microbial interactions determine whether a bacterial strain survives an expansion to new territory. In our work, we studied competitive range expansions in a model system of three Escherichia coli strains. In this system, a colicin producing strain competed with a colicin resistant, and with a colicin sensitive strain for new territory. Genetic engineering allowed us to tune the strains' growth rates and to study their expansion in distinct ecological scenarios (with either cyclic or hierarchical dominance). The control over growth rates also enabled us to construct and to validate a predictive computational model of the bacterial dynamics. The model rested on an agent-based, coarse-grained description of the expansion process and we conducted independent experiments on the growth of single-strain colonies for its parametrization. Furthermore, the model considered the long-range nature of the toxin interaction between strains. The integration of experimental analysis with computational modeling made it possible to quantify how the level of biodiversity depends on the interplay between bacterial growth rates, the initial composition of the inoculum, and the toxin range.

  13. Effects of forest expansion on mountain grassland

    DEFF Research Database (Denmark)

    Guidi, Claudia; Magid, Jakob; Rodeghiero, Mirco

    2014-01-01

    Background and aims. Grassland abandonment followed by forest succession is the dominant land-use change in the European Alps. We studied the impact of current forest expansion on mountain grassland on changes in physical soil organic carbon (SOC) fractions along a land-use and management gradient...

  14. Stakeholder Support for School Food Policy Expansions

    Science.gov (United States)

    Pettigrew, Simone; Pescud, Melanie; Donovan, Robert J.

    2012-01-01

    The aim of this study was to assess the extent to which parents and school-based stakeholders (principals, teachers, canteen managers and Parents & Citizen Committee presidents) are supportive of potential expansions to a new school food policy. Eight additional policy components elicited in preliminary focus groups with parents and 19 additional…

  15. Global Expansion and English Language Learning

    Science.gov (United States)

    Andrade, Maureen Snow

    2016-01-01

    Demand for higher education is global. As institutions extend opportunities beyond their borders, English language proficiency must be considered. This chapter focuses on considerations related to global expansion, with an emphasis on the role of distance English language courses and the distinct considerations in their development.

  16. Taylor series expansions for stationary Markov chains

    NARCIS (Netherlands)

    Heidergott, B.F.; Hordijk, A.

    2003-01-01

    We study Taylor series expansions of stationary characteristics of general-state-space Markov chains. The elements of the Taylor series are explicitly calculated and a lower bound for the radius of convergence of the Taylor series is established. The analysis provided in this paper applies to the

  17. Term Dependence: Truncating the Bahadur Lazarsfeld Expansion.

    Science.gov (United States)

    Losee, Robert M., Jr.

    1994-01-01

    Studies the performance of probabilistic information retrieval systems using differing statistical dependence assumptions when estimating the probabilities inherent in the retrieval model. Experimental results using the Bahadur Lazarsfeld expansion on the Cystic Fibrosis database are discussed that suggest that incorporating term dependence…

  18. Revisting expansive learning for knowledge production and ...

    African Journals Online (AJOL)

    Revisting expansive learning for knowledge production and capability development at postgraduate level in Higher Education Studies. R Niemann. Abstract. Higher education in South Africa is challenged by academic and social demands. Universities, therefore, have to produce graduates who will be able to function ...

  19. On the Convergence of the Virial Expansion

    NARCIS (Netherlands)

    Ramawadh, S.D.

    2015-01-01

    The virial expansion appears in statistical mechanics, an area where physics and mathematics intersect. Throughout this thesis we will mostly ignore the physics and mainly focus on the mathematical aspects. This is a deliberate choice, made for two reasons. Firstly, there are several books that

  20. Critical point anomalies include expansion shock waves

    NARCIS (Netherlands)

    Nannen, N.R.; Guardone, A.; Colonna, P.

    2014-01-01

    From first-principle fluid dynamics, complemented by a rigorous state equation accounting for critical anomalies, we discovered that expansion shock waves may occur in the vicinity of the liquid-vapor critical point in the two-phase region. Due to universality of near-critical thermodynamics, the

  1. The replication of expansive production knowledge

    DEFF Research Database (Denmark)

    Wæhrens, Brian Vejrum; Yang, Cheng; Madsen, Erik Skov

    2012-01-01

    Purpose – With the aim to support offshore production line replication, this paper specifically aims to explore the use of templates and principles to transfer expansive productive knowledge embedded in a production line and understand the contingencies that influence the mix of these approaches....

  2. Expansion patterns and parallaxes for planetary nebulae

    Science.gov (United States)

    Schönberner, D.; Balick, B.; Jacob, R.

    2018-02-01

    Aims: We aim to determine individual distances to a small number of rather round, quite regularly shaped planetary nebulae by combining their angular expansion in the plane of the sky with a spectroscopically measured expansion along the line of sight. Methods: We combined up to three epochs of Hubble Space Telescope imaging data and determined the angular proper motions of rim and shell edges and of other features. These results are combined with measured expansion speeds to determine individual distances by assuming that line of sight and sky-plane expansions are equal. We employed 1D radiation-hydrodynamics simulations of nebular evolution to correct for the difference between the spectroscopically measured expansion velocities of rim and shell and of their respective shock fronts. Results: Rim and shell are two independently expanding entities, driven by different physical mechanisms, although their model-based expansion timescales are quite similar. We derive good individual distances for 15 objects, and the main results are as follows: (i) distances derived from rim and shell agree well; (ii) comparison with the statistical distances in the literature gives reasonable agreement; (iii) our distances disagree with those derived by spectroscopic methods; (iv) central-star "plateau" luminosities range from about 2000 L⊙ to well below 10 000 L⊙, with a mean value at about 5000 L⊙, in excellent agreement with other samples of known distance (Galactic bulge, Magellanic Clouds, and K648 in the globular cluster M 15); (v) the central-star mass range is rather restricted: from about 0.53 to about 0.56 M⊙, with a mean value of 0.55 M⊙. Conclusions: The expansion measurements of nebular rim and shell edges confirm the predictions of radiation-hydrodynamics simulations and offer a reliable method for the evaluation of distances to suited objects. Results of this paper are based on observations made with the NASA/ESA Hubble Space Telescope in Cycle 16 (GO11122

  3. 216-B-3 expansion ponds closure plan

    Energy Technology Data Exchange (ETDEWEB)

    1994-10-01

    This document describes the activities for clean closure under the Resource Conservation and Recovery Act of 1976 (RCRA) of the 216-B-3 Expansion Ponds. The 216-B-3 Expansion Ponds are operated by the US Department of Energy, Richland Operations Office (DOE-RL) and co-operated by Westinghouse Hanford Company (Westinghouse Hanford). The 216-B-3 Expansion Ponds consists of a series of three earthen, unlined, interconnected ponds that receive waste water from various 200 East Area operating facilities. The 3A, 3B, and 3C ponds are referred to as Expansion Ponds because they expanded the capability of the B Pond System. Waste water (primarily cooling water, steam condensate, and sanitary water) from various 200 East Area facilities is discharged to the Bypass pipe (Project X-009). Water discharged to the Bypass pipe flows directly into the 216-B-3C Pond. The ponds were operated in a cascade mode, where the Main Pond overflowed into the 3A Pond and the 3A Pond overflowed into the 3C Pond. The 3B Pond has not received waste water since May 1985; however, when in operation, the 3B Pond received overflow from the 3A Pond. In the past, waste water discharges to the Expansion Ponds had the potential to have contained mixed waste (radioactive waste and dangerous waste). The radioactive portion of mixed waste has been interpreted by the US Department of Energy (DOE) to be regulated under the Atomic Energy Act of 1954; the dangerous waste portion of mixed waste is regulated under RCRA.

  4. Experimental Analysis on Flow Expansion Over Fan

    Science.gov (United States)

    Sittoni, L.; Paola, C.

    2005-12-01

    We present experimental evidence on the occurrence of large angles of flow expansion with no flow separation over depositional fans. The evolution of a number of self-formed experimental fans was analyzed using overhead images and detailed topographic surveys. Angles of flow expansion up to 45 degrees were found in association with a characteristic bed curvature. Although precise measurements indicate that transverse curvature appeared to slightly decrease downstream over the fans, an approximately constant value of curvature of about 0.1 (r/W = 0.1, where r is the dimensional curvature and W is the maximum width of the fan) fits well all fan sections analyzed. In addition, we found that bed curvature shows a weak proportional dependence with fan expansion angles (alpha around 20 degrees, where alpha is the local plan angle). The curvature appears sufficient to explain the common occurrence of unchannelized, simple fans with opening angles, and hence rates of bedload divergence, much larger than would be predicted from jet theory. We have also analyzed fan development. In our experiments, an instability phenomenon causes a sudden increase in channel width, in association with the formation of a scour. A common development pattern was observed: the upstream-migrating scour initiates flow expansion, inducing in turn the formation of a transient concave heart-shaped fan shape that then slowly develops into a final, steady cone-shaped deposit. Most of the deposition appears to occur during the initial expansion phase. During final steady conditions, fans were also observed to reach values of L/0.5W (L is the final fan length and W is the fan width) approximately constant and in the range 2-4.

  5. Medicaid Expansion and Infant Mortality in the United States.

    Science.gov (United States)

    Bhatt, Chintan B; Beck-Sagué, Consuelo M

    2018-01-18

    To explore the effect of Medicaid expansion on US infant mortality rate. We examined data from 2010 to 2016 and 2014 to 2016 to compare infant mortality rates in states and Washington, DC, that accepted the Affordable Care Act Medicaid expansion (Medicaid expansion states) and states that did not (non-Medicaid expansion states), stratifying data by race/ethnicity. Mean infant mortality rate in non-Medicaid expansion states rose (6.4 to 6.5) from 2014 to 2016 but declined in Medicaid expansion states (5.9 to 5.6). Mean difference in infant mortality rate in Medicaid expansion versus non-Medicaid expansion states increased from 0.573 (P = .08) in 2014 to 0.838 in 2016 (P = .006) because of smaller declines in non-Medicaid expansion (11.0%) than in Medicaid expansion (15.2%) states. The 14.5% infant mortality rate decline from 11.7 to 10.0 in African American infants in Medicaid expansion states was more than twice that in non-Medicaid expansion states (6.6%: 12.2 to 11.4; P = .012). Infant mortality rate decline was greater in Medicaid expansion states, with greater declines among African American infants. Future research should explore what aspects of Medicaid expansion may improve infant survival. (Am J Public Health. Published online ahead of print January 18, 2018: e1-e3. doi:10.2105/AJPH.2017.304218).

  6. Expansion of World Drylands Under Global Warming

    Science.gov (United States)

    Feng, S.; Fu, Q.; Hu, Q. S.

    2012-12-01

    The world drylands including both semi-arid and arid regions comprise of one-third of the global land surfaces, which support 14% of the world's inhabitants and a significant share of the world agriculture. Because of meager annual precipitation and large potential evaporative water loss, the ecosystems over drylands are fragile and sensitive to the global change. By analyzing the observations during 1948-2008 and 20 fully coupled climate model simulations from CMIP5 for the period 1900-2100, this study evaluated the changes of the world drylands that are defined with a modified form of the Thornthwaite's moisture index. The results based on observational data showed that the world drylands are steadily expanding during the past 60 years. The areas occupied by drylands in 1994-2008 is about 2.0×10^6km^2 (or 4%) larger than the average during the 1950s. Such an expansion is also a robust feature in the simulations of the 20 global climate models, though the rate is much smaller in the models. A stronger expanding rate is projected during the first half of this century than the simulations in the last century, followed by accelerating expansion after 2050s under the high greenhouse gas emission scenario (RCP8.5). By the end of this century, the world drylands are projected to be over 58×10^6km^2 (or 11% increase compared to the 1961-1990 climatology). The projected expansion of drylands, however, is not homogeneous over the world drylands, with major expansion of arid regions over the southwest North America, the northern fringe of Africa, southern Africa and Australia. Major expansions of semi-arid regions are projected over the north side of the Mediterranean, southern Africa, North and South America. The global warming is the main factor causing the increase of potential evapotranspiration estimated by Penman-Monteith algorithm, which in turn dominants the expansion of drylands. The widening of Hadley cell, which has impact on both temperature and precipitation

  7. Defining chemical expansion: the choice of units for the stoichiometric expansion coefficient

    DEFF Research Database (Denmark)

    Marrocchelli, Dario; Chatzichristodoulou, Christodoulos; Bishop, Sean R.

    2014-01-01

    Chemical expansion refers to the spatial dilation of a material that occurs upon changes in its composition. When this dilation is caused by a gradual, iso-structural increase in the lattice parameter with composition, it is related to the composition change by the stoichiometric expansion coeffi...... are provided for changes in oxygen content in fluorite, perovskite, and Ruddlesden-Popper (K2NiF4) phase materials used in solid oxide fuel cells....

  8. REGENERATIVE GAS TURBINES WITH DIVIDED EXPANSION

    DEFF Research Database (Denmark)

    Elmegaard, Brian; Qvale, Einar Bjørn

    2004-01-01

    their efficiency are always of interest. Recently, two independent studies have proposed recuperated gas turbines to be configured with the turbine expansion divided, in order to obtain higher efficiency. The idea is to operate the system with a gas generator and a power turbine, and use the gas from the gas......Recuperated gas turbines are currently drawing an increased attention due to the recent commercialization of micro gas turbines with recuperation. This system may reach a high efficiency even for the small units of less than 100 kW. In order to improve the economics of the plants, ways to improve...... divided expansion can be advantageous under certain circumstances. But, in order for todays micro gas turbines to be competitive, the thermodynamic efficiencies will have to be rather high. This requires that all component efficiencies including the recuperator effectiveness will have to be high...

  9. Off-diagonal expansion quantum Monte Carlo.

    Science.gov (United States)

    Albash, Tameem; Wagenbreth, Gene; Hen, Itay

    2017-12-01

    We propose a Monte Carlo algorithm designed to simulate quantum as well as classical systems at equilibrium, bridging the algorithmic gap between quantum and classical thermal simulation algorithms. The method is based on a decomposition of the quantum partition function that can be viewed as a series expansion about its classical part. We argue that the algorithm not only provides a theoretical advancement in the field of quantum Monte Carlo simulations, but is optimally suited to tackle quantum many-body systems that exhibit a range of behaviors from "fully quantum" to "fully classical," in contrast to many existing methods. We demonstrate the advantages, sometimes by orders of magnitude, of the technique by comparing it against existing state-of-the-art schemes such as path integral quantum Monte Carlo and stochastic series expansion. We also illustrate how our method allows for the unification of quantum and classical thermal parallel tempering techniques into a single algorithm and discuss its practical significance.

  10. Locally-smeared operator product expansions

    Energy Technology Data Exchange (ETDEWEB)

    Monahan, Christopher; Orginos, Kostantinos

    2014-12-01

    We propose a "locally-smeared Operator Product Expansion" (sOPE) to decompose non-local operators in terms of a basis of locally-smeared operators. The sOPE formally connects nonperturbative matrix elements of smeared degrees of freedom, determined numerically using the gradient flow, to non-local operators in the continuum. The nonperturbative matrix elements do not suffer from power-divergent mixing on the lattice, provided the smearing scale is kept fixed in the continuum limit. The presence of this smearing scale prevents a simple connection to the standard operator product expansion and therefore requires the construction of a two-scale formalism. We demonstrate the feasibility of our approach using the example of real scalar field theory.

  11. Morse basis expansion applied to diatomic molecules

    Energy Technology Data Exchange (ETDEWEB)

    Lima, Emanuel F. de, E-mail: eflima@rc.unesp.br [Departamento de Estatística, Matemática Aplicada e Computação, Instituto de Geociências e Ciências Exatas, Universidade Estadual Paulista – UNESP, Rio Claro, São Paulo 13506-900 (Brazil)

    2012-02-20

    This work explores the use of the eigenfunctions of the Morse potential with a infinite barrier at long range to solve the radial Schrödinger equation for diatomic molecules. Analytical formulas are obtained for the kinetic energy operator matrix elements in the Morse basis. The Morse basis expansion is applied to find the vibrational–rotational levels of the sodium molecule in the electronic ground state. -- Highlights: ► The Morse potential basis is invoked to find the rovibrational levels of diatomic molecules. ► Analytical formulas for the kinetic energy operator in the Morse basis are obtained. ► The results of the Morse basis expansion show good agreement with the Fourier Grid technique.

  12. Off-diagonal expansion quantum Monte Carlo

    Science.gov (United States)

    Albash, Tameem; Wagenbreth, Gene; Hen, Itay

    2017-12-01

    We propose a Monte Carlo algorithm designed to simulate quantum as well as classical systems at equilibrium, bridging the algorithmic gap between quantum and classical thermal simulation algorithms. The method is based on a decomposition of the quantum partition function that can be viewed as a series expansion about its classical part. We argue that the algorithm not only provides a theoretical advancement in the field of quantum Monte Carlo simulations, but is optimally suited to tackle quantum many-body systems that exhibit a range of behaviors from "fully quantum" to "fully classical," in contrast to many existing methods. We demonstrate the advantages, sometimes by orders of magnitude, of the technique by comparing it against existing state-of-the-art schemes such as path integral quantum Monte Carlo and stochastic series expansion. We also illustrate how our method allows for the unification of quantum and classical thermal parallel tempering techniques into a single algorithm and discuss its practical significance.

  13. 6th International Symposium on Thermal Expansion

    CERN Document Server

    1978-01-01

    This 6th International Symposium on Thermal Expansion, the first outside the USA, was held on August 29-31, 1977 at the Gull Harbour Resort on Hecla Island, Manitoba, Canada. Symposium Chairman was Ian D. Peggs, Atomic Energy of Canada Limited, and our continuing sponsor was CINDAS/Purdue University. We made considerable efforts to broaden the base this year to include more users of expansion data but with little success. We were successful, however, in establishing a session on liquids, an area which is receiving more attention as a logical extension to the high-speed thermophysical property measurements on materials at temperatures close to their melting points. The Symposium had good international representation but the overall attendance was, disappointingly, relatively low. Neverthe­ less, this enhanced the informal atmosphere throughout the meeting with a resultant frank exchange of information and ideas which all attendees appreciated. A totally new item this year was the presentation of a bursary to ...

  14. Asymptotic expansions for the Gaussian unitary ensemble

    DEFF Research Database (Denmark)

    Haagerup, Uffe; Thorbjørnsen, Steen

    2012-01-01

    Let g : R ¿ C be a C8-function with all derivatives bounded and let trn denote the normalized trace on the n × n matrices. In Ref. 3 Ercolani and McLaughlin established asymptotic expansions of the mean value ¿{trn(g(Xn))} for a rather general class of random matrices Xn, including the Gaussian...... aj(g), j ¿ N, as distributions (in the sense of L. Schwarts). We derive a similar asymptotic expansion for the covariance Cov{Trn[f(Xn)], Trn[g(Xn)]}, where f is a function of the same kind as g, and Trn = n trn. Special focus is drawn to the case where and for ¿, µ in C\\R. In this case the mean...

  15. Frostless heat pump having thermal expansion valves

    Science.gov (United States)

    Chen, Fang C [Knoxville, TN; Mei, Viung C [Oak Ridge, TN

    2002-10-22

    A heat pump system having an operable relationship for transferring heat between an exterior atmosphere and an interior atmosphere via a fluid refrigerant and further having a compressor, an interior heat exchanger, an exterior heat exchanger, a heat pump reversing valve, an accumulator, a thermal expansion valve having a remote sensing bulb disposed in heat transferable contact with the refrigerant piping section between said accumulator and said reversing valve, an outdoor temperature sensor, and a first means for heating said remote sensing bulb in response to said outdoor temperature sensor thereby opening said thermal expansion valve to raise suction pressure in order to mitigate defrosting of said exterior heat exchanger wherein said heat pump continues to operate in a heating mode.

  16. Bond return predictability in expansions and recessions

    DEFF Research Database (Denmark)

    Engsted, Tom; Møller, Stig Vinther; Jensen, Magnus David Sander

    We document that over the period 1953-2011 US bond returns are predictable in expansionary periods but unpredictable during recessions. This result holds in both in-sample and out-of-sample analyses and using both univariate regressions and combination forecasting techniques. A simulation study...... but negative in recessions. The results are also consistent with tests showing that the expectations hypothesis of the term structure holds in recessions but not in expansions. However, the results for bonds are in sharp contrast to results for stocks showing that stock returns are predictable in recessions...... but not in expansions. Thus, our results indicate that there is not a common predictive pattern of stock and bond returns associated with the state of the economy....

  17. Cellular Responses to Auxin: Division versus Expansion

    OpenAIRE

    Perrot-Rechenmann, Catherine

    2010-01-01

    The phytohormone auxin is a major regulator of plant growth and development. Many aspects of these processes depend on the multiple controls exerted by auxin on cell division and cell expansion. The detailed mechanisms by which auxin controls these essential cellular responses are still poorly understood, despite recent progress in the identification of auxin receptors and components of auxin signaling pathways. The purpose of this review is to provide an overview of the present knowledge of ...

  18. Multipole expansion in the quantum hall effect

    Energy Technology Data Exchange (ETDEWEB)

    Cappelli, Andrea [INFN, Sezione di Firenze,Via G. Sansone 1, 50019 Sesto Fiorentino, Firenze (Italy); Randellini, Enrico [INFN, Sezione di Firenze,Via G. Sansone 1, 50019 Sesto Fiorentino, Firenze (Italy); Dipartimento di Fisica, Università di Firenze,Via G. Sansone 1, 50019 Sesto Fiorentino, Firenze (Italy)

    2016-03-15

    The effective action for low-energy excitations of Laughlin’s states is obtained by systematic expansion in inverse powers of the magnetic field. It is based on the W-infinity symmetry of quantum incompressible fluids and the associated higher-spin fields. Besides reproducing the Wen and Wen-Zee actions and the Hall viscosity, this approach further indicates that the low-energy excitations are extended objects with dipolar and multipolar moments.

  19. Spatial Linkage and Urban Expansion: AN Urban Agglomeration View

    Science.gov (United States)

    Jiao, L. M.; Tang, X.; Liu, X. P.

    2017-09-01

    Urban expansion displays different characteristics in each period. From the perspective of the urban agglomeration, studying the spatial and temporal characteristics of urban expansion plays an important role in understanding the complex relationship between urban expansion and network structure of urban agglomeration. We analyze urban expansion in the Yangtze River Delta Urban Agglomeration (YRD) through accessibility to and spatial interaction intensity from core cities as well as accessibility of road network. Results show that: (1) Correlation between urban expansion intensity and spatial indicators such as location and space syntax variables is remarkable and positive, while it decreases after rapid expansion. (2) Urban expansion velocity displays a positive correlation with spatial indicators mentioned above in the first (1980-1990) and second (1990-2000) period. However, it exhibits a negative relationship in the third period (2000-2010), i.e., cities located in the periphery of urban agglomeration developing more quickly. Consequently, the hypothesis of convergence of urban expansion in rapid expansion stage is put forward. (3) Results of Zipf's law and Gibrat's law show urban expansion in YRD displays a convergent trend in rapid expansion stage, small and medium-sized cities growing faster. This study shows that spatial linkage plays an important but evolving role in urban expansion within the urban agglomeration. In addition, it serves as a reference to the planning of Yangtze River Delta Urban Agglomeration and regulation of urban expansion of other urban agglomerations.

  20. SPATIAL LINKAGE AND URBAN EXPANSION: AN URBAN AGGLOMERATION VIEW

    Directory of Open Access Journals (Sweden)

    L. M. Jiao

    2017-09-01

    Full Text Available Urban expansion displays different characteristics in each period. From the perspective of the urban agglomeration, studying the spatial and temporal characteristics of urban expansion plays an important role in understanding the complex relationship between urban expansion and network structure of urban agglomeration. We analyze urban expansion in the Yangtze River Delta Urban Agglomeration (YRD through accessibility to and spatial interaction intensity from core cities as well as accessibility of road network. Results show that: (1 Correlation between urban expansion intensity and spatial indicators such as location and space syntax variables is remarkable and positive, while it decreases after rapid expansion. (2 Urban expansion velocity displays a positive correlation with spatial indicators mentioned above in the first (1980–1990 and second (1990–2000 period. However, it exhibits a negative relationship in the third period (2000–2010, i.e., cities located in the periphery of urban agglomeration developing more quickly. Consequently, the hypothesis of convergence of urban expansion in rapid expansion stage is put forward. (3 Results of Zipf’s law and Gibrat's law show urban expansion in YRD displays a convergent trend in rapid expansion stage, small and medium-sized cities growing faster. This study shows that spatial linkage plays an important but evolving role in urban expansion within the urban agglomeration. In addition, it serves as a reference to the planning of Yangtze River Delta Urban Agglomeration and regulation of urban expansion of other urban agglomerations.

  1. Frequency dependent thermal expansion in binary viscoelasticcomposites

    Energy Technology Data Exchange (ETDEWEB)

    Berryman, James G.

    2007-12-01

    The effective thermal expansion coefficient beta* of abinary viscoelastic composite is shown to be frequency dependent even ifthe thermal expansion coefficients beta A and beta B of both constituentsare themselves frequency independent. Exact calculations for binaryviscoelastic systems show that beta* is related to constituent valuesbeta A, beta B, volume fractions, and bulk moduli KA, KB, as well as tothe overall bulk modulus K* of the composite system. Then, beta* isdetermined for isotropic systems by first bounding (or measuring) K* andtherefore beta*. For anisotropic systems with hexagonal symmetry, theprincipal values of the thermal expansion beta*perp and beta*para can bedetermined exactly when the constituents form a layered system. In allthe examples studied, it is shown explicitly that the eigenvectors of thethermoviscoelastic system possess non-negative dissipation -- despite thecomplicated analytical behavior of the frequency dependent thermalexpansivities themselves. Methods presented have a variety ofapplications from fluid-fluid mixtures to fluid-solid suspensions, andfrom fluid-saturated porous media to viscoelastic solid-solidcomposites.

  2. Tissue expansion: Concepts, techniques and unfavourable results

    Directory of Open Access Journals (Sweden)

    Milind S Wagh

    2013-01-01

    Full Text Available The phenomenon of tissue expansion is observed in nature all the time. The same properties of the human skin to stretch and expand and yield extra skin if placed under continuous stress over a prolonged period of time has been utilised for reconstructive purposes with the help of a silicon balloon inserted under the skin and progressively filled with saline. The technique of tissue expansion is now more than three decades old and has been a value addition to our armamentarium in reconstructive surgery in all parts of the body. However, it still requires careful patient selection, meticulous planning and faultless execution to successfully carry out the process, which usually lasts for more than 8-12 weeks and involves two sittings of surgery. Any compromise in this process can lead to unfavourable results and complications, some minor, which allow continuance of the process to attain the expected goal and others major, which force abandonment of the process without reaching the expected goal. This article seeks to highlight the intricacies of the concept of tissue expansion, the technique related to flawless execution of the process and likely complications with emphasis on their management. We also present our results from a personal series of 138 patients operated over a period of 18 years between 1994 and 2012.

  3. Precision Quantum Chromodynamics From Heavy Quark Expansions

    CERN Document Server

    Benson, D G

    2005-01-01

    The heavy quark expansion is applied to the semileptonic width of b → c and b → u transitions along with the moments of various decay distributions in the semileptonic b → c transitions. The resulting expressions can be used to improve the precision with which we can extract the values of the CKM matrix elements Vcb and Vub from the data. Heavy quark parameters like mb and m2p are also obtained with values that are completely consistent with theoretical expectations. The observed agreement between the theoretical predictions of the heavy quark expansion and the experimental data tightly constrain the theoretical uncertainty. The heavy quark expansion can also be applied to the photon energy moments in B → Xsγ. The first two of these moments are directly related to mb and m2p . The experimentally imposed cuts on the photon energy spectrum introduce biases into the extracted values of these parameters. Correcting for these biases generates a remarkable agreem...

  4. Lessons from Early Medicaid Expansions Under Health Reform..

    Data.gov (United States)

    U.S. Department of Health & Human Services — Lessons from Early Medicaid Expansions Under Health Reform, Interviews with Medicaid Officials In a new study entitled Lessons from Early Medicaid Expansions Under...

  5. NiTi Expansion in Operated Unilateral Cleft Palate Patients

    Directory of Open Access Journals (Sweden)

    K Y Poornima

    2011-01-01

    Conclusion : NiTi expansion in operated cleft patients, showed mainly orthodontic expansion. The significant change in the maxillary inter- molar region is due to the direct placement of NiTi palatal expander to 16, 26.

  6. Following Surgically Assisted Rapid Palatal Expansion, Do Tooth-Borne or Bone-Borne Appliances Provide More Skeletal Expansion and Dental Expansion?

    Science.gov (United States)

    Hamedi-Sangsari, Adrien; Chinipardaz, Zahra; Carrasco, Lee

    2017-10-01

    The aim of this study was to compare outcome measurements of skeletal and dental expansion with bone-borne (BB) versus tooth-borne (TB) appliances after surgically assisted rapid palatal expansion (SARPE). This study was performed to provide quantitative measurements that will help the oral surgeon and orthodontist in selecting the appliance with, on average, the greatest amount of skeletal expansion and the least amount of dental expansion. A computerized database search was performed using PubMed, EBSCO, Cochrane, Scopus, Web of Science, and Google Scholar on publications in reputable oral surgery and orthodontic journals. A systematic review and meta-analysis was completed with the predictor variable of expansion appliance (TB vs BB) and outcome measurement of expansion (in millimeters). Of 487 articles retrieved from the 6 databases, 5 articles were included, 4 with cone-beam computed tomographic (CBCT) data and 1 with non-CBCT 3-dimensional cast data. There was a significant difference in skeletal expansion (standardized mean difference [SMD], 0.92; 95% confidence interval [CI], 0.54-1.30; P < .001) in favor of BB rather than TB appliances. However, there was no significant difference in dental expansion (SMD, 0.05; 95% CI, -0.24 to 0.34; P = .03). According to the literature, to achieve more effective skeletal expansion and minimize dental expansion after SARPE, a BB appliance should be favored. Copyright © 2017 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

  7. Detection automatique de bulles HI en expansion

    Science.gov (United States)

    Daigle, Anik

    Plusieurs cavités en expansion observées dans le gaz d'hydrogène neutre galactique ont été associées à la présence d'étoiles massives présentant d'intenses vents stellaires ou à des explosions de supernovae. Ces bulles, qui sont remplies de gaz très chaud ( T = 10 5 -10 7 K), tracent donc à la fois les étoiles massives et la phase chaude et ionisée du gaz interstellaire. La morphologie de ces bulles est instable et généralement perturbée par la multitude de structures et de phénomènes existant dans le milieu interstellaire. Leur détection par inspection visuelle est donc difficile et subjective. L'objet de cette thèse est le développement d'une technique de détection automatique et objective de bulles en expansion dans le gaz d'hydrogène neutre de la Voie lactée. Les bulles à progéniteurs stellaires présentent toutes des vitesses d'expansion comprises entre 6 et 19 km s -1 . Une telle caractéristique peut généralement être reconnue dans les spectres en vitesse des cubes de données à 21 cm de l'hydrogène neutre. Notre technique de détection a donc été fondée sur la reconnaissance automatique de la signature d'une expansion à [6, 19] km s -1 dans les spectres en vitesse. La caractérisation et la généralisation de la signature dynamique propre à une bulle en expansion a été confiée à des réseaux de neurones artificiels. Des validations subséquentes, dont certaines liées à la morphologie, ont ensuite été appliquées. La technique a été testée sur onze bulles connues, dont dix ont pu être détectées. La technique a aussi été employée pour la réalisation d'un relevé dans la région du bras de Persée. La distribution spatiale des objets détectés s'est révélée suivre la distribution des étoiles du disque de la Voie lactée. De plus, la distribution selon le rayon et selon la vitesse d'expansion des bulles détectées de rayons plus petits que 10 pc correspondent aux distributions dérivées du mod

  8. 36 CFR 72.42 - Expansion and new development.

    Science.gov (United States)

    2010-07-01

    ... 36 Parks, Forests, and Public Property 1 2010-07-01 2010-07-01 false Expansion and new development... INTERIOR URBAN PARK AND RECREATION RECOVERY ACT OF 1978 Grants for Recovery Action Program Development, Rehabilitation and Innovation § 72.42 Expansion and new development. (a) Expansion. Because the UPARR Program is...

  9. Electrical Resistance Alloys and Low-Expansion Alloys

    DEFF Research Database (Denmark)

    Kjer, Torben

    1996-01-01

    The article gives an overview of electrical resistance alloys and alloys with low thermal expansion. The electrical resistance alloys comprise resistance alloys, heating alloys and thermostat alloys. The low expansion alloys comprise alloys with very low expansion coefficients, alloys with very low...

  10. Rapid replacement of bridge deck expansion joints study - phase I.

    Science.gov (United States)

    2014-12-01

    Bridge deck expansion joints are used to allow for movement of the bridge deck due to thermal expansion, dynamics loading, and : other factors. More recently, expansion joints have also been utilized to prevent the passage of winter de-icing chemical...

  11. 46 CFR 61.15-12 - Nonmetallic expansion joints.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Nonmetallic expansion joints. 61.15-12 Section 61.15-12... INSPECTIONS Periodic Tests of Piping Systems § 61.15-12 Nonmetallic expansion joints. (a) Nonmetallic expansion joints must be examined externally at each inspection for certification and periodic inspection...

  12. 14 CFR 23.969 - Fuel tank expansion space.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Fuel tank expansion space. 23.969 Section 23.969 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT....969 Fuel tank expansion space. Each fuel tank must have an expansion space of not less than two...

  13. High flux expansion divertor studies in NSTX

    Energy Technology Data Exchange (ETDEWEB)

    Soukhanovskii, V A; Maingi, R; Bell, R E; Gates, D A; Kaita, R; Kugel, H W; LeBlanc, B P; Maqueda, R; Menard, J E; Mueller, D; Paul, S F; Raman, R; Roquemore, A L

    2009-06-29

    Projections for high-performance H-mode scenarios in spherical torus (ST)-based devices assume low electron collisionality for increased efficiency of the neutral beam current drive. At lower collisionality (lower density), the mitigation techniques based on induced divertor volumetric power and momentum losses may not be capable of reducing heat and material erosion to acceptable levels in a compact ST divertor. Divertor geometry can also be used to reduce high peak heat and particle fluxes by flaring a scrape-off layer (SOL) flux tube at the divertor plate, and by optimizing the angle at which the flux tube intersects the divertor plate, or reduce heat flow to the divertor by increasing the length of the flux tube. The recently proposed advanced divertor concepts [1, 2] take advantage of these geometry effects. In a high triangularity ST plasma configuration, the magnetic flux expansion at the divertor strike point (SP) is inherently high, leading to a reduction of heat and particle fluxes and a facilitated access to the outer SP detachment, as has been demonstrated recently in NSTX [3]. The natural synergy of the highly-shaped high-performance ST plasmas with beneficial divertor properties motivated a further systematic study of the high flux expansion divertor. The National Spherical Torus Experiment (NSTX) is a mid-sized device with the aspect ratio A = 1.3-1.5 [4]. In NSTX, the graphite tile divertor has an open horizontal plate geometry. The divertor magnetic configuration geometry was systematically changed in an experiment by either (1) changing the distance between the lower divertor X-point and the divertor plate (X-point height h{sub X}), or by (2) keeping the X-point height constant and increasing the outer SP radius. An initial analysis of the former experiment is presented below. Since in the divertor the poloidal field B{sub {theta}} strength is proportional to h{sub X}, the X-point height variation changed the divertor plasma wetted area due to

  14. Zirconium titanate: stability and thermal expansion; Titanato de circonio: estabilidad termodinamica y expansion termica

    Energy Technology Data Exchange (ETDEWEB)

    Lopez-Lopez, E.; Moreno, R.; Baudin, C.

    2011-07-01

    Zirconium titanate is a well known compound in the field of electro ceramics, although it has also been used in catalyst and sensors applications. The crystallographic thermal expansion anisotropy of this compound makes it a potential candidate as constituent of structural components. In general, to assure the structural integrity and microstructural homogeneity of a ceramic piece, relatively low cooling rates from the fabrication temperature are required. This requirement is essential for zirconium titanate because thermal expansion as well as phase distribution is affected by small variations in the composition and cooling rate. This work reviews the available data on the phase equilibrium relationships in the systems ZrO{sub 2}-TiO{sub 2} and ZrO{sub 2}-TiO{sub 2}-Y{sub 2}O{sub 3}. The main discrepancies as well as the possible origins of them are discussed. Additionally, the crystallographic thermal expansion data in the current literature are reviewed. (Author) 56 refs.

  15. Private randomness expansion with untrusted devices

    Energy Technology Data Exchange (ETDEWEB)

    Colbeck, Roger; Kent, Adrian, E-mail: rcolbeck@perimeterinstitute.ca, E-mail: a.p.a.kent@damtp.cam.ac.uk [Perimeter Institute for Theoretical Physics, 31 Caroline Street North, Waterloo, ON N2L 2Y5 (Canada)

    2011-03-04

    Randomness is an important resource for many applications, from gambling to secure communication. However, guaranteeing that the output from a candidate random source could not have been predicted by an outside party is a challenging task, and many supposedly random sources used today provide no such guarantee. Quantum solutions to this problem exist, for example a device which internally sends a photon through a beamsplitter and observes on which side it emerges, but, presently, such solutions require the user to trust the internal workings of the device. Here, we seek to go beyond this limitation by asking whether randomness can be generated using untrusted devices-even ones created by an adversarial agent-while providing a guarantee that no outside party (including the agent) can predict it. Since this is easily seen to be impossible unless the user has an initially private random string, the task we investigate here is private randomness expansion. We introduce a protocol for private randomness expansion with untrusted devices which is designed to take as input an initially private random string and produce as output a longer private random string. We point out that private randomness expansion protocols are generally vulnerable to attacks that can render the initial string partially insecure, even though that string is used only inside a secure laboratory; our protocol is designed to remove this previously unconsidered vulnerability by privacy amplification. We also discuss extensions of our protocol designed to generate an arbitrarily long random string from a finite initially private random string. The security of these protocols against the most general attacks is left as an open question.

  16. Maxillary protraction after surgically assisted maxillary expansion

    Directory of Open Access Journals (Sweden)

    Laurindo Zanco Furquim

    2010-06-01

    Full Text Available This case report describes the orthodontic treatment of a 32-year-old woman with a Class III malocclusion, whose chief compliant was her dentofacial esthetics. The pretreatment lateral cephalometric tracings showed the presence of a Class III dentoskeletal malocclusion with components of maxillary deficiency. After discussion with the patient, the treatment option included surgically assisted rapid maxillary expansion (SARME followed by orthopedic protraction (Sky Hook and Class III elastics. Patient compliance was excellent and satisfactory dentofacial esthetics was achieved after treatment completion.

  17. Eta-Expansion Does The Trick

    DEFF Research Database (Denmark)

    Danvy, Olivier; Malmkjær, Karoline; Palsberg, Jens

    1995-01-01

    Partial-evaluation folklore has it that massaging one's source programs can make them specialize better. In Jones, Gomard, and Sestoft's recent textbook, a whole chapter is dedicated to listing such “binding-time improvements”: nonstandard use of continuation-passing style, eta-expansion, and a p......Partial-evaluation folklore has it that massaging one's source programs can make them specialize better. In Jones, Gomard, and Sestoft's recent textbook, a whole chapter is dedicated to listing such “binding-time improvements”: nonstandard use of continuation-passing style, eta...

  18. Eta-Expansion Does The Trick

    DEFF Research Database (Denmark)

    Danvy, Olivier; Malmkjær, Karoline; Palsberg, Jens

    1996-01-01

    Partial-evaluation folklore has it that massaging one's source programs can make them specialize better. In Jones, Gomard, and Sestoft's recent textbook, a whole chapter is dedicated to listing such “binding-time improvements”: nonstandard use of continuation-passing style, eta-expansion, and a p......Partial-evaluation folklore has it that massaging one's source programs can make them specialize better. In Jones, Gomard, and Sestoft's recent textbook, a whole chapter is dedicated to listing such “binding-time improvements”: nonstandard use of continuation-passing style, eta...

  19. Eta-expansion does The Trick

    DEFF Research Database (Denmark)

    Danvy, Olivier; Malmkjær, Karoline; Palsberg, Jens

    1996-01-01

    Partial-evaluation folklore has it that massaging one's source programs can make them specialize better. In Jones, Gomard, and Sestoft's recent textbook, a whole chapter is dedicated to listing such “binding-time improvements”: nonstandard use of continuation-passing style, eta-expansion, and a p......Partial-evaluation folklore has it that massaging one's source programs can make them specialize better. In Jones, Gomard, and Sestoft's recent textbook, a whole chapter is dedicated to listing such “binding-time improvements”: nonstandard use of continuation-passing style, eta...

  20. Exploring the expansion history of the universe.

    Science.gov (United States)

    Linder, Eric V

    2003-03-07

    Exploring the recent expansion history of the universe promises insights into the cosmological model, the nature of dark energy, and potentially clues to high energy physics theories and gravitation. We examine the extent to which precision distance-redshift observations can map out the history, including the acceleration-deceleration transition, and the components and equations of state of the energy density. We consider the ability to distinguish between various dynamical scalar field models for the dark energy, as well as higher dimension and alternate gravity theories. Finally, we present a new, advantageous parametrization for the study of dark energy.

  1. Unique expansions and intersections of Cantor sets

    Science.gov (United States)

    Baker, Simon; Kong, Derong

    2017-04-01

    To each α \\in (1/3,1/2) we associate the Cantor set Γα:={∑i=1∞ɛiαi:ɛi∈{0,1}, i⩾1}. In this paper we consider the intersection {{ Γ }α}{\\cap}≤ft({{ Γ }α}+t\\right) for any translation t\\in {R} . We pay special attention to those t with a unique {-1, 0, 1} α-expansion, and study the set Dα:={dimH(Γα∩(Γα+t)):t has a unique {-1,0,1} α-expansion}. We prove that there exists a transcendental number {αKL}≈ 0.394 33\\ldots such that: {{D}α} is finite for α \\in ≤ft({αKL},1/2\\right), {{D}{αKL}}} is infinitely countable, and {{D}α} contains an interval for α \\in ≤ft(1/3,{{αKL}\\right). We also prove that {{D}α} equals ≤ft[0,\\frac{log 2}{-log α}\\right] if and only if α \\in ≤ft(1/3,\\frac{3-\\sqrt{5}}{2}\\right] . As a consequence of our investigation we prove some results on the possible values of \\text{di}{{\\text{m}}H}≤ft({{ Γ }α}{\\cap}≤ft({{ Γ }α}+t\\right)\\right) when {{ Γ }α}{\\cap}≤ft({{ Γ }α}+t\\right) is a self-similar set. We also give examples of t with a continuum of {-1, 0, 1} α-expansions for which we can explicitly calculate \\text{di}{{\\text{m}}H}≤ft({{ Γ }α}{\\cap}≤ft({{ Γ }α}+t\\right)\\right), and for which {{ Γ }α}{\\cap}≤ft({{ Γ }α}+t\\right) is a self-similar set. We also construct α and t for which {{ Γ }α}{\\cap}≤ft({{ Γ }α}+t\\right) contains only transcendental numbers. Our approach makes use of digit frequency arguments and a lexicographic characterisation of those t with a unique {-1, 0, 1} α-expansion.

  2. Capacity Expansion Modeling for Storage Technologies

    Energy Technology Data Exchange (ETDEWEB)

    Hale, Elaine; Stoll, Brady; Mai, Trieu

    2017-04-03

    The Resource Planning Model (RPM) is a capacity expansion model designed for regional power systems and high levels of renewable generation. Recent extensions capture value-stacking for storage technologies, including batteries and concentrating solar power with storage. After estimating per-unit capacity value and curtailment reduction potential, RPM co-optimizes investment decisions and reduced-form dispatch, accounting for planning reserves; energy value, including arbitrage and curtailment reduction; and three types of operating reserves. Multiple technology cost scenarios are analyzed to determine level of deployment in the Western Interconnection under various conditions.

  3. Landownership Concentration and the Expansion of Education

    DEFF Research Database (Denmark)

    Cinnirella, Francesco; Hornung, Erik

    2016-01-01

    We study the relationship between large landownership concentration and the expansion of mass education in nineteenth-century Prussia. Cross-sectional estimates show a negative association between landownership concentration and enrollment rates. Fixed-effects panel estimates indicate that regions...... with an initially stronger landownership concentration exhibit increasing enrollment rates. This relationship is not driven by differences in the supply of schooling. We argue that the implementation of agricultural reforms including the stepwise abolition of serfdom is an important driver of the change...

  4. Exploring the expansion history of the universe

    Energy Technology Data Exchange (ETDEWEB)

    Linder, Eric V.

    2002-08-30

    Exploring the recent expansion history of the universe promises insights into the cosmological model, the nature of dark energy, and potentially clues to high energy physics theories and gravitation. They examine the extent to which precision distance-redshift observations can map out the history, including the acceleration-deceleration transition, and the components and equations of state of the energy density. They consider the ability to distinguish between various dynamical scalar field models for the dark energy, as well as higher dimension and alternate gravity theories. Finally, they present a new, advantageous parametrization for the study of dark energy.

  5. Further analysis of the connected moments expansion

    Energy Technology Data Exchange (ETDEWEB)

    Amore, Paolo; Rodriguez, Martin [Facultad de Ciencias, Universidad de Colima, Bernal Diaz del Castillo 340, Colima, Colima (Mexico); Fernandez, Francisco M, E-mail: paolo.amore@gmail.com, E-mail: fernande@quimica.unlp.edu.ar, E-mail: martinalexander.rv@gmail.com [INIFTA (UNLP, CCT La Plata-CONICET), Division Quimica Teorica, Blvd. 113 S/N, Sucursal 4, Casilla de Correo 16, 1900 La Plata (Argentina)

    2011-12-16

    By means of simple quantum-mechanical models we show that under certain conditions the main assumptions of the connected moments expansion (CMX) are no longer valid. In particular, we consider two-level systems: the harmonic oscillator and the pure quartic oscillator. Although derived from such simple models, we think that the results of this investigation may be of utility in future applications of the approach to realistic problems. We show that a straightforward analysis of the CMX exponential parameters may provide a clear indication of the success of the approach. (paper)

  6. Laboratory simulation of Hot Jupiters atmosphere expansion

    Science.gov (United States)

    Prokopov, P. A.; Shaikhislamov, I. F.; Zakharov, Yu P.; Posukh, V. G.; Melekhov, A. V.; Boyarintsev, E. L.; Ponomarenko, A. G.

    2017-11-01

    Hot Jupiters (HJ) are exoplanets, gas giants with low orbits (≤ 0.1 a.u.). The stellar X-ray and ultraviolet (XUV) radiation energy deposition result in heating ionization and the consequent expansion of planetary atmosphere. Expansion of upper atmosphere under certain conditions could be so large that the majority of light atmospheric constituents overcome the gravitational binding and escape from the planet in a form of hydrodynamic wind. Besides interaction of two counter-streaming plasma flows (stellar wind and ionized upper layers of planet atmosphere), each of this flows interact with planetary magnetic field. In such complex situation laboratory simulation can provide data that can’t be obtained by computer simulation or observation. Experiment was carried out on KI-1 facility: high-vacuum chamber 5m long, 1.2 m in diameter with pressure ∼ 10-6 Torr. Magnetic dipole with two attached laser targets played the role of a planet, and background plasma from θ-pinch used for simulation of stellar wind. As a result, data on a behavior of plasma density and magnetic field were obtained. The novel phenomenon was registered: magnetic field is transferred by the cloud of laser plasma, which was not observed before in experiments or calculations.

  7. Improved Expansion of Random Cayley Graphs

    Directory of Open Access Journals (Sweden)

    Po-Shen Loh

    2004-12-01

    Full Text Available In Random Cayley Graphs and Expanders, N. Alon and Y. Roichman proved that for every ε > 0 there is a finite c(ε such that for any sufficiently large group G, the expected value of the second largest (in absolute value eigenvalue of the normalized adjacency matrix of the Cayley graph with respect to c(ε log |G| random elements is less than ε. We reduce the number of elements to c(εlog D(G (for the same c, where D(G is the sum of the dimensions of the irreducible representations of G. In sufficiently non-abelian families of groups (as measured by these dimensions, log D(G is asymptotically (1/2log|G|. As is well known, a small eigenvalue implies large graph expansion (and conversely; see Tanner84 and AlonMilman84-2,AlonMilman84-1. For any specified eigenvalue or expansion, therefore, random Cayley graphs (of sufficiently non-abelian groups require only half as many edges as was previously known.

  8. Completeness relations and resonant state expansions

    Energy Technology Data Exchange (ETDEWEB)

    Lind, P. (Department of Mathematical Physics, Lund Institute of Technology, P.O. Box 118, S-221 00 Lund (Sweden))

    1993-05-01

    The completeness properties of the discrete set of bound states, virtual states, and resonant states characterizing the system of a single nonrelativistic particle moving in a central cutoff potential are investigated. We do not limit ourselves to the restricted form of completeness that can be obtained from Mittag-Leffler theory in this case. Instead we will make use of the information contained in the asymptotic behavior of the discrete states to get a new approach to the question of eventual overcompleteness. Using the theory of analytic functions we derive a number of completeness relations in terms of discrete states and complex continuum states and give some criteria for how to use them to form resonant state expansions of functions, matrix elements, and Green's functions. In cases where the integral contribution vanishes, the discrete part of the expansions is of the same form as that given by Mittag-Leffler theory but with regularized inner products. We also consider the possibility of using the discrete states as basis in a matrix representation.

  9. Contradictions of TNCs’ Foreign Economic Expansion

    Directory of Open Access Journals (Sweden)

    Melnikov Aleksandr Borisovich

    2014-11-01

    Full Text Available Some directions of the external economic expansion of multinational corporations in modern conditions of globalization, the contradictions generated by these conditions and the conflicts in the system of world economy are presented in the article. The global strategy of functioning of multinational corporation professes the principle of “double standards”. Multinational corporations, on the one hand, support liberalization and internationalization in scales of world reproduction, on the other hand – further redistribution of spheres of influence, and imposing the new world economic order. The functional role of modern multinational corporations is inconsistent. Though they stimulate the tendency of increasing the competitiveness, concentration of the capital and production, at the same time, the monopolization and institutional barriers created by multinational corporation and its structural divisions. Multinational corporations determine the competitive struggle, implement the sanitation mechanism and optimization of world economy. The diversification of multinational corporations’ activity promotes the generation of new requirements and the markets (information, innovations, technologies, services, etc. where individual subjects and competitive forces are formed. It is caused by a progressive functional role of modern multinational corporations in the global economy. Massive penetration into the international business, external expansion of transnational monopolies stimulates economic growth in host countries, promotes specialization, division of labor, cooperation. At the same time, the monopolist form of these processes inevitably leads to numerous negative phenomena, a slow down and inconsistent development of production in the countries-recipients.

  10. Extended Plefka expansion for stochastic dynamics

    Science.gov (United States)

    Bravi, B.; Sollich, P.; Opper, M.

    2016-05-01

    We propose an extension of the Plefka expansion, which is well known for the dynamics of discrete spins, to stochastic differential equations with continuous degrees of freedom and exhibiting generic nonlinearities. The scenario is sufficiently general to allow application to e.g. biochemical networks involved in metabolism and regulation. The main feature of our approach is to constrain in the Plefka expansion not just first moments akin to magnetizations, but also second moments, specifically two-time correlations and responses for each degree of freedom. The end result is an effective equation of motion for each single degree of freedom, where couplings to other variables appear as a self-coupling to the past (i.e. memory term) and a coloured noise. This constitutes a new mean field approximation that should become exact in the thermodynamic limit of a large network, for suitably long-ranged couplings. For the analytically tractable case of linear dynamics we establish this exactness explicitly by appeal to spectral methods of random matrix theory, for Gaussian couplings with arbitrary degree of symmetry.

  11. Thin metastructures with engineered thermal expansion

    Science.gov (United States)

    Gdoutos, Eleftherios E.

    The geometry and constituent materials of metastructures can be used to engineer the thermal expansion coefficient. In this thesis, we design, fabricate, and test thin thermally stable metastructures consisting of bi-metallic unit cells and show how the coefficient of thermal expansion (CTE) of these metastructures can be finely and coarsely tuned by varying the CTE of the constituent materials and the unit cell geometry. Planar and three-dimensional finite element method modeling is used to drive the design and inform experiments, and predict the response of these metastructures. We demonstrate computationally the significance of out-of-plane effects in the metastructure response. We develop an experimental setup using digital image correlation and an infrared camera to experimentally measure full displacement and temperature fields during testing and accurately measure the metastructures' CTE. We experimentally demonstrate high aspect ratio metastructures of Ti/Al and Kovar/Al which exhibit near-zero and negative CTE, respectively. We demonstrate robust fabrication procedures for thermally stable samples with high aspect ratios in thin foil and thin film scales. We investigate the lattice structure and mechanical properties of thin films comprising a near-zero CTE metastructure. The mechanics developed in this work can be used to engineer metastructures of arbitrary CTE and can be extended to three dimensions.

  12. Spontaneous thermal expansion of nematic elastomers

    Science.gov (United States)

    Tajbakhsh, A. R.; Terentjev, E. M.

    2001-10-01

    We study the monodomain (single-crystal) nematic elastomer materials, all side-chain siloxane polymers with the same mesogenic groups and crosslinking density, but differing in the type of crosslinking. Increasing the proportion of long di-functional segments of main-chain nematic polymer, acting as network crosslinking, results in dramatic changes in the uniaxial equilibrium thermal expansion on cooling from the isotropic phase. At higher concentration of main chains their behaviour dominates the elastomer properties. At low concentration of main-chain material, we detect two distinct transitions at different temperatures, one attributed to the main-chain, the other to the side-chain component. The effective uniaxial anisotropy of nematic rubber, r(T)=ell_{allel}/ell_{bot} proportional to the effective nematic order parameter Q(T), is given by an average of the two components and thus reflects the two-transition nature of thermal expansion. The experimental data is compared with the theoretical model of ideal nematic elastomers; applications in high-amplitude thermal actuators are discussed in the end.

  13. Optimizing a Query by Transformation and Expansion.

    Science.gov (United States)

    Glocker, Katrin; Knurr, Alexander; Dieter, Julia; Dominick, Friederike; Forche, Melanie; Koch, Christian; Pascoe Pérez, Analie; Roth, Benjamin; Ückert, Frank

    2017-01-01

    In the biomedical sector not only the amount of information produced and uploaded into the web is enormous, but also the number of sources where these data can be found. Clinicians and researchers spend huge amounts of time on trying to access this information and to filter the most important answers to a given question. As the formulation of these queries is crucial, automated query expansion is an effective tool to optimize a query and receive the best possible results. In this paper we introduce the concept of a workflow for an optimization of queries in the medical and biological sector by using a series of tools for expansion and transformation of the query. After the definition of attributes by the user, the query string is compared to previous queries in order to add semantic co-occurring terms to the query. Additionally, the query is enlarged by an inclusion of synonyms. The translation into database specific ontologies ensures the optimal query formulation for the chosen database(s). As this process can be performed in various databases at once, the results are ranked and normalized in order to achieve a comparable list of answers for a question.

  14. Transmission network expansion planning with simulation optimization

    Energy Technology Data Exchange (ETDEWEB)

    Bent, Russell W [Los Alamos National Laboratory; Berscheid, Alan [Los Alamos National Laboratory; Toole, G. Loren [Los Alamos National Laboratory

    2010-01-01

    Within the electric power literatW''e the transmi ssion expansion planning problem (TNEP) refers to the problem of how to upgrade an electric power network to meet future demands. As this problem is a complex, non-linear, and non-convex optimization problem, researchers have traditionally focused on approximate models. Often, their approaches are tightly coupled to the approximation choice. Until recently, these approximations have produced results that are straight-forward to adapt to the more complex (real) problem. However, the power grid is evolving towards a state where the adaptations are no longer easy (i.e. large amounts of limited control, renewable generation) that necessitates new optimization techniques. In this paper, we propose a generalization of the powerful Limited Discrepancy Search (LDS) that encapsulates the complexity in a black box that may be queJied for information about the quality of a proposed expansion. This allows the development of a new optimization algOlitlun that is independent of the underlying power model.

  15. Tensor integrand reduction via Laurent expansion

    Energy Technology Data Exchange (ETDEWEB)

    Hirschi, Valentin [SLAC, National Accelerator Laboratory,2575 Sand Hill Road, Menlo Park, CA 94025-7090 (United States); Peraro, Tiziano [Higgs Centre for Theoretical Physics, School of Physics and Astronomy,The University of Edinburgh,Edinburgh EH9 3JZ, Scotland (United Kingdom)

    2016-06-09

    We introduce a new method for the application of one-loop integrand reduction via the Laurent expansion algorithm, as implemented in the public C++ library Ninja. We show how the coefficients of the Laurent expansion can be computed by suitable contractions of the loop numerator tensor with cut-dependent projectors, making it possible to interface Ninja to any one-loop matrix element generator that can provide the components of this tensor. We implemented this technique in the Ninja library and interfaced it to MADLOOP, which is part of the public MADGRAPH5{sub A}MC@NLO framework. We performed a detailed performance study, comparing against other public reduction tools, namely CUTTOOLS, SAMURAI, IREGI, PJFRY++ and GOLEM95. We find that Ninja outperforms traditional integrand reduction in both speed and numerical stability, the latter being on par with that of the tensor integral reduction tool GOLEM95 which is however more limited and slower than Ninja. We considered many benchmark multi-scale processes of increasing complexity, involving QCD and electro-weak corrections as well as effective non-renormalizable couplings, showing that Ninja’s performance scales well with both the rank and multiplicity of the considered process.

  16. Renormalized Wick expansion for a modified PQCD

    Energy Technology Data Exchange (ETDEWEB)

    Cabo Montes de Oca, Alejandro [Instituto de Cibernetica, Matematica y Fisica, Group of Theoretical Physics, Vedado, La Habana (Cuba); Abdus Salam International Centre for Theoretical Physics, Trieste (Italy)

    2008-05-15

    The renormalization scheme for the Wick expansion of a modified version of the perturbative QCD introduced in previous works is discussed. Massless QCD is considered by implementing the usual multiplicative scaling of the gluon and quark wave functions and vertices. However, also massive quark and gluon counterterms are allowed in this massless theory since the condensates are expected to generate masses. A natural set of expansion parameters of the physical quantities is introduced: the coupling itself and the two masses m{sub q} and m{sub g} associated to quarks and gluons, respectively. This procedure allows one to implement a dimensional transmutation effect through these new mass scales. A general expression for the new generating functional in terms of the mass parameters m{sub q} and m{sub g} is obtained in terms of integrals over arbitrary but constant gluon or quark fields in each case. Further, the one loop potential is evaluated in more detail in the case when only the quark condensate is retained. This lowest order result again indicates the dynamical generation of quark condensates in the vacuum. (orig.)

  17. The Game Object Model and Expansive Learning: Creation, Instantiation, Expansion, and Re-representation

    Science.gov (United States)

    Amory, Alan; Molomo, Bolepo; Blignaut, Seugnet

    2011-01-01

    In this paper, the collaborative development, instantiation, expansion and re-representation as research instrument of the Game Object Model (GOM) are explored from a Cultural Historical Activity Theory perspective. The aim of the paper is to develop insights into the design, integration, evaluation and use of video games in learning and teaching.…

  18. The SWAP Upper Atmosphere Expansion Benchmark

    Science.gov (United States)

    Fuller-Rowell, T. J.; Zesta, E.; Basu, S.; Black, C.; Emmert, J. T.; Sutton, E. K.; Thayer, J. P.; Codrescu, M.; Fedrizzi, M.; Tobiska, W. K.; Crowley, G.; Pilinski, M.; Bowman, B. R.; Woods, T. N.; Chamberlin, P. C.

    2016-12-01

    Atmospheric expansion during extreme events gives rise to increases in neutral density at low-Earth orbit altitudes, which poses two distinct risks to operational spacecraft. The first is the direct effect of enhanced drag on the spacecraft, changing its orbit, increasing the uncertainty of its position, and reducing the orbital lifetime. The second is the indirect effect of atmospheric expansion on the ability to monitor the trajectories of debris, including objects with high area-to-mass ratios, for collision avoidance at all times. The Benchmark for neutral density is defined relative to the empirical neutral density reference models, e.g., JB2008 or NRLMSIS-00. These models are used as a reference in order to extrapolate the response to a 100-year and theoretical maximum event. The Benchmark is also defined for neutral winds: in-track winds change apparent density along an orbit; cross-track winds influence orbit trajectory. The Benchmark is established at three altitudes: 250 km, 400 km, and 850 km, and quantifies the impact from solar ultraviolet radiation (EUV and FUV) at low, medium, and high solar activity on timescales greater than one day; EUV enhancement during impulsive events, such as solar flares; and coronal mass ejections (CMEs) driving geomagnetic storms. A 100-year and theoretical maximum estimate of the peak daily F10.7 proxy are 390 and 500 units, respectively, which would increase global mean density by 100% and 160% at 400 km altitude above the empirical model values at an F10.7 of 240 units. Estimates for a 100-year flare are X30 with a theoretical maximum of X40. The response to an X30 or X40 flare would produce a 75% and 135% density increase, respectively, on the dayside at 400 km altitude at a median solar flux level of 150 sfu. For a Carrington storm the thermospheric temperature is expected to exceed 4000 K, and neutral density is predicted to exceed empirical model estimates of the response to a Bastille or Halloween-like storm by a

  19. Progressive GAA.TTC repeat expansion in human cell lines.

    Science.gov (United States)

    Ditch, Scott; Sammarco, Mimi C; Banerjee, Ayan; Grabczyk, Ed

    2009-10-01

    Trinucleotide repeat expansion is the genetic basis for a sizeable group of inherited neurological and neuromuscular disorders. Friedreich ataxia (FRDA) is a relentlessly progressive neurodegenerative disorder caused by GAA.TTC repeat expansion in the first intron of the FXN gene. The expanded repeat reduces FXN mRNA expression and the length of the repeat tract is proportional to disease severity. Somatic expansion of the GAA.TTC repeat sequence in disease-relevant tissues is thought to contribute to the progression of disease severity during patient aging. Previous models of GAA.TTC instability have not been able to produce substantial levels of expansion within an experimentally useful time frame, which has limited our understanding of the molecular basis for this expansion. Here, we present a novel model for studying GAA.TTC expansion in human cells. In our model system, uninterrupted GAA.TTC repeat sequences display high levels of genomic instability, with an overall tendency towards progressive expansion. Using this model, we characterize the relationship between repeat length and expansion. We identify the interval between 88 and 176 repeats as being an important length threshold where expansion rates dramatically increase. We show that expansion levels are affected by both the purity and orientation of the repeat tract within the genomic context. We further demonstrate that GAA.TTC expansion in our model is independent of cell division. Using unique reporter constructs, we identify transcription through the repeat tract as a major contributor to GAA.TTC expansion. Our findings provide novel insight into the mechanisms responsible for GAA.TTC expansion in human cells.

  20. Conflation: a new type of accelerated expansion

    Energy Technology Data Exchange (ETDEWEB)

    Fertig, Angelika; Lehners, Jean-Luc; Mallwitz, Enno [Max-Planck-Institute for Gravitational Physics (Albert-Einstein-Institute),Am Mühlenberg 1, Potsdam-Golm, 14476 (Germany)

    2016-08-31

    In the framework of scalar-tensor theories of gravity, we construct a new kind of cosmological model that conflates inflation and ekpyrosis. During a phase of conflation, the universe undergoes accelerated expansion, but with crucial differences compared to ordinary inflation. In particular, the potential energy is negative, which is of interest for supergravity and string theory where both negative potentials and the required scalar-tensor couplings are rather natural. A distinguishing feature of the model is that, for a large parameter range, it does not significantly amplify adiabatic scalar and tensor fluctuations, and in particular does not lead to eternal inflation and the associated infinities. We also show how density fluctuations in accord with current observations may be generated by adding a second scalar field to the model. Conflation may be viewed as complementary to the recently proposed anamorphic universe of Ijjas and Steinhardt.

  1. DISRUPTING SHOCKS IN POSTWAR GLOBAL ECONOMIC EXPANSION

    Directory of Open Access Journals (Sweden)

    Dumitru FILIPEANU

    2016-06-01

    Full Text Available The coherence of the global economic system, created by its upswing in the first postwar decades, started to crumble in the ’70s. The destabilizing shocks affected the entire world, but in an uneven manner, in different geographical areas and at different times, being felt most acutely, with devastating economic and social effects, in Third World countries. Although the developed countries were affected as well, they always had means to combat or to diminish the adverse effects of the crises, leading to "gentler" consequences. This paper focuses on four main aspects in postwar global economic expansion, namely: the ’70s – the international monetary crisis and the oil shocks; the foreign debt crisis; the Latin American debt crisis, the Asian financial crises and the current global crisis.

  2. A non-perturbative operator product expansion

    Energy Technology Data Exchange (ETDEWEB)

    Bietenholz, W. [Universidad Nacional Autonoma de Mexico, Distrito Federal (Mexico). Inst. de Ciencias Nucleares; Cundy, N.; Goeckeler, M. [Regensburg Univ. (DE). Inst. fuer Theoretische Physik] (and others)

    2009-10-15

    Nucleon structure functions can be observed in Deep Inelastic Scattering experiments, but it is an outstanding challenge to confront them with fully non-perturbative QCD results. For this purpose we investigate the product of electromagnetic currents (with large photonmomenta) between quark states (of low momenta). By means of an Operator Product Expansion the structure function can be decomposed into matrix elements of local operators, and Wilson coefficients. For consistency both have to be computed non-perturbatively. Here we present precision results for a set of Wilson coefficients. They are evaluated from propagators for numerous quark momenta on the lattice, where the use of chiral fermions suppresses undesired operator mixing. This overdetermines the Wilson coefficients, but reliable results can be extracted by means of a Singular Value Decomposition. (orig.)

  3. The replication of expansive production knowledge

    DEFF Research Database (Denmark)

    Wæhrens, Brian Vejrum; Yang, Cheng; Madsen, Erik Skov

    2012-01-01

    ; and (2) rather than being viewed as alternative approaches, templates and principles should be seen as complementary once the transfer motive moves beyond pure replication. Research limitations – The concepts introduced in this paper were derived from two Danish cases. While acceptable for theory......Purpose – With the aim to support offshore production line replication, this paper specifically aims to explore the use of templates and principles to transfer expansive productive knowledge embedded in a production line and understand the contingencies that influence the mix of these approaches...... exploration, the small sample size is an obvious limitation for generalisation. Practical implications – A roadmap for knowledge transfer within the replication of a production line is suggested, which, together with four managerial suggestions, provides strong support and clear directions to managers...

  4. Sectoral and regional expansion of emissions trading

    Energy Technology Data Exchange (ETDEWEB)

    Boehringer, Christoph; Bouwe, Dijkstra; Rosendahl, Knut Einar

    2011-07-01

    We consider an international emissions trading scheme with partial sectoral and regional coverage. Sectoral and regional expansion of the trading scheme is beneficial in aggregate, but not necessarily for individual countries. We simulate international CO{sub 2} emission quota markets using marginal abatement cost functions and the Copenhagen 2020 climate policy targets for selected countries that strategically allocate emissions in a bid to manipulate the quota price. Quota exporters and importers generally have conflicting interests about admitting more countries to the trading coalition, and our results indicate that some countries may lose substantially when the coalition expands in terms of new countries. For a given coalition, expanding sectoral coverage makes most countries better off, but some countries (notably the USA and Russia) may lose out due to loss of strategic advantages. In general, exporters tend to have stronger strategic power than importers.(Author)

  5. Population Genetics of Three Dimensional Range Expansions

    Science.gov (United States)

    Lavrentovich, Maxim; Nelson, David

    2014-03-01

    We develop a simple model of genetic diversity in growing spherical cell clusters, where the growth is confined to the cluster surface. This kind of growth occurs in cells growing in soft agar, and can also serve as a simple model of avascular tumors. Mutation-selection balance in these radial expansions is strongly influenced by scaling near a neutral, voter model critical point and by the inflating frontier. We develop a scaling theory to describe how the dynamics of mutation-selection balance is cut off by inflation. Genetic drift, i.e., local fluctuations in the genetic diversity, also plays an important role, and can lead to the extinction even of selectively advantageous strains. We calculate this extinction probability, taking into account the effect of rough population frontiers.

  6. Expansion of museums in Central Europe?

    Directory of Open Access Journals (Sweden)

    Jagodzińska, Katarzyna

    2015-06-01

    Full Text Available The paper presents reflections on the specificity of collections and museums of contemporary art in Central Europe and considers a possibility of creating a regional alternative for the West. The analysis is conducted in the context of the expansionist policy of contemporary museums – notably the Louvre, the Guggenheim Foundation, and the Hermitage – whose numerous new development projects gave rise to a number of dilemmas in the museological world. The author discusses global "museum brands" that invest in Central Europe and addresses the possible profits of the expansion of such "concerns" for culture in the region, as well as emphasises the potential of the region itself, which may be used for its development without the avail of the internationally renowned collectors' names.

  7. Large-spin expansions of GKP strings

    Science.gov (United States)

    Floratos, Emmanuel; Georgiou, George; Linardopoulos, Georgios

    2014-03-01

    We demonstrate that the large-spin expansion of the energy of Gubser-Klebanov-Polyakov (GKP) strings that rotate in ℝ × S2 and AdS3 can be expressed in terms of Lambert's W-function. We compute the leading, subleading and next-to-subleading series of exponential corrections to the infinite-volume dispersion relation of GKP strings that rotate in ℝ × S2. These strings are dual to the long = 4 SYM operators +… and provide their scaling dimensions at strong coupling. We also show that the strings obey a short-long (strings) duality. For the folded GKP strings that spin inside AdS3 and are dual to twist-2 operators, we confirm the known formulas for the leading and next-to-leading coefficients of their anomalous dimensions and derive the corresponding expressions for the next-to-next-to-leading coefficients.

  8. EMPIRE ULTIMATE EXPANSION: RESONANCES AND COVARIANCES.

    Energy Technology Data Exchange (ETDEWEB)

    HERMAN,M.; MUGHABGHAB, S.F.; OBLOZINSKY, P.; ROCHMAN, D.; PIGNI, M.T.; KAWANO, T.; CAPOTE, R.; ZERKIN, V.; TRKOV, A.; SIN, M.; CARSON, B.V.; WIENKE, H. CHO, Y.-S.

    2007-04-22

    The EMPIRE code system is being extended to cover the resolved and unresolved resonance region employing proven methodology used for the production of new evaluations in the recent Atlas of Neutron Resonances. Another directions of Empire expansion are uncertainties and correlations among them. These include covariances for cross sections as well as for model parameters. In this presentation we concentrate on the KALMAN method that has been applied in EMPIRE to the fast neutron range as well as to the resonance region. We also summarize role of the EMPIRE code in the ENDF/B-VII.0 development. Finally, large scale calculations and their impact on nuclear model parameters are discussed along with the exciting perspectives offered by the parallel supercomputing.

  9. The worldwide expansion of the Argentine ant

    DEFF Research Database (Denmark)

    Vogel, Valerie; Pedersen, Jes Søe; Giraud, Tatiana

    2010-01-01

    Aim The aim of this study was to determine the number of successful establishments of the invasive Argentine ant outside native range and to see whether introduced supercolonies have resulted from single or multiple introductions. We also compared the genetic diversity of native versus introduced...... supercolonies to assess the size of the propagules (i.e. the number of founding individuals) at the origin of the introduced supercolonies. Location Global. Methods We used mitochondrial DNA (mtDNA) markers and microsatellite loci to study 39 supercolonies of the Argentine ant Linepithema humile covering both......) and secondary introductions (from sites with established invasive supercolonies) were important in the global expansion of the Argentine ant. In combination with the similar social organization of colonies in the native and introduced range, this indicates that invasiveness did not evolve recently as a unique...

  10. Quantization Noise Shaping on Arbitrary Frame Expansions

    Directory of Open Access Journals (Sweden)

    Boufounos Petros T

    2006-01-01

    Full Text Available Quantization noise shaping is commonly used in oversampled A/D and D/A converters with uniform sampling. This paper considers quantization noise shaping for arbitrary finite frame expansions based on generalizing the view of first-order classical oversampled noise shaping as a compensation of the quantization error through projections. Two levels of generalization are developed, one a special case of the other, and two different cost models are proposed to evaluate the quantizer structures. Within our framework, the synthesis frame vectors are assumed given, and the computational complexity is in the initial determination of frame vector ordering, carried out off-line as part of the quantizer design. We consider the extension of the results to infinite shift-invariant frames and consider in particular filtering and oversampled filter banks.

  11. The new Medicaid debate: expansion or retrenchment?

    Science.gov (United States)

    2001-01-01

    Health advocates are facing a sea-change in Washington. Comprehensive federal health care reform eluded the nation under the Clinton Administration, but incremental progress through state-based Medicaid expansions and new CHIP programs was widespread, giving rise to some innovative state efforts to cover more of the uninsured. Washington's support was instrumental in those efforts, but the second Bush Administration seems intent on reversing that direction. To protect--and build upon--these nascent Medicaid efforts, advocates will have to mount careful strategies in defense of Medicaid. This States of Health looks at the dangers that may lie ahead and suggests how advocates can respond to keep Medicaid moving in the right direction.

  12. A collisionless plasma thruster plume expansion model

    Science.gov (United States)

    Merino, Mario; Cichocki, Filippo; Ahedo, Eduardo

    2015-06-01

    A two-fluid model of the unmagnetized, collisionless far region expansion of the plasma plume for gridded ion thrusters and Hall effect thrusters is presented. The model is integrated into two semi-analytical solutions valid in the hypersonic case. These solutions are discussed and compared against the results from the (exact) method of characteristics; the relative errors in density and velocity increase slowly axially and radially and are of the order of 10-2-10-3 in the cases studied. The plasma density, ion flux and ambipolar electric field are investigated. A sensitivity analysis of the problem parameters and initial conditions is carried out in order to characterize the far plume divergence angle in the range of interest for space electric propulsion. A qualitative discussion of the physics of the secondary plasma plume is also provided.

  13. The Dynamics of Regional and Global Expansion

    DEFF Research Database (Denmark)

    Geisler Asmussen, Christian; Nielsen, Bo Bernhard; Osegowitsch, Tom

    2015-01-01

    presence over time. The authors test the resulting hypotheses using sales data from a sample of 220 of the world’s largest MNEs over the period 1995-2005. The authors focus specifically on the relationship between levels of market penetration inside and outside the home region and rates of change in each......Purpose – The purpose of this paper is to model and test the dynamics of home-regional and global penetration by multi-national enterprises (MNEs). Design/methodology/approach – Drawing on international business (IB) theory, the authors model MNEs adjusting their home-regional and global market...... domain. Findings – The authors demonstrate that MNEs do penetrate both home-regional and global markets, often simultaneously, and that penetration levels often oscillate within an MNE over time. The authors show firms’ rates of regional and global expansion to be affected by their existing regional...

  14. Expansive focal cemento-osseous dysplasia.

    Science.gov (United States)

    Bulut, Emel Uzun; Acikgoz, Aydan; Ozan, Bora; Zengin, Ayse Zeynep; Gunhan, Omer

    2012-01-01

    To present a case of expansive focal cemento-osseous dysplasia and emphasize the importance of differential diagnosis. Cemento-osseous dysplasia is categorized into three subtypes on the basis of the clinical and radiographic features: Periapical, focal and florid. The focal type exhibits a single site of involvement in any tooth-bearing or edentulous area of the jaws. These lesions are usually asymptomatic; therefore, they are frequently diagnosed incidentally during routine radiographic examinations. Lesions are usually benign, show limited growth, and do not require further surgical intervention, but periodic follow-up is recommended because occasionally, this type of dysplasia progresses into florid osseous dysplasia and simple bone cysts are formed. A 24-year-old female patient was referred to our clinic for swelling in the left edentulous mandibular premolarmolar region and felt discomfort when she wore her prosthetics. She had no pain, tenderness or paresthesia. Clinical examination showed that the swelling in the posterior mandible that was firm, nonfluctuant and covered by normal mucosa. On panoramic radiography and computed tomography, a well defined lesion of approximately 1.5 cm in diameter of mixed density was observed. The swelling increased slightly in size over 2 years making it difficult to use prosthetics and, therefore, the lesion was totally excised under local anesthesia, and surgical specimens were submitted for histopathological examination. The histopathological diagnosis was focal cemento-osseous dysplasia. In the present case, because of the increasing size of the swelling making it difficult to use prosthetics, young age of the patient and localization of the lesion, in the initial examination, cemento-ossifying fibroma was suspected, and the lesion was excised surgically; the histopathological diagnosis confirmed it as focal cemento-osseous dysplasia. We present a case of expansive focal cemento-osseous dysplasia. Differential diagnosis

  15. Expansion by regions: revealing potential and Glauber regions automatically

    Energy Technology Data Exchange (ETDEWEB)

    Jantzen, Bernd [RWTH Aachen University, Institut fuer Theoretische Teilchenphysik und Kosmologie, Aachen (Germany); Smirnov, Alexander V. [Moscow State University, Scientific Research Computing Center, Moscow (Russian Federation); KIT, Institut fuer Theoretische Teilchenphysik, Karlsruhe (Germany); Smirnov, Vladimir A. [Moscow State University, Skobeltsyn Institute of Nuclear Physics, Moscow (Russian Federation); KIT, Institut fuer Theoretische Teilchenphysik, Karlsruhe (Germany)

    2012-09-15

    When performing asymptotic expansions using the strategy of expansion by regions, it is a non-trivial task to find the relevant regions. The recently published Mathematica code asy.m automates this task, but it has not been able to detect potential regions in threshold expansions or Glauber regions. In this work we present an algorithm and its implementation in the update asy2.m which also reveals potential and Glauber regions automatically. (orig.)

  16. Anisotropic thermal expansion in crystals of different categories

    Science.gov (United States)

    Zamkovskaya, A.; Maksimova, E.

    2015-12-01

    The three-dimensional (3D) indicatory surfaces of thermal expansion in crystals of different categories were constructed in program MathCad. Indicatory surface of thermal expansion is a sphere, spheroid, ellipsoid or surface of multiple parts, depending on the category of the crystal symmetry. The symmetry elements of thermal expansion include the symmetry elements of the point group of the crystal according Neumann's Principle.

  17. Effect of rapid maxillary expansion on sleep characteristics in children

    OpenAIRE

    Navya Ashok; N. K. Sapna Varma; Ajith, V. V.; Siby Gopinath

    2014-01-01

    Introduction: Rapid maxillary expansion (RME) is an orthopedic treatment procedure routinely used to treat constricted maxillary arches and also a potential additional treatment in children presenting with sleep-disordered breathing (SDB). Aims and Objectives: The main objective of this study was to evaluate the effects of RME on sleep characteristics in children. Materials and Methods: Polysomnography was done on children of 8-13 years of age before expansion (T0), after expansion (T1) and a...

  18. Orthopedic Treatment of Maxillary Expansion: A Review of the Literature

    OpenAIRE

    Sylvia Ng; Minjie Li; Yanqi Yang

    2015-01-01

    Transverse maxillary deficiency, no matter in adolescents or in adults, is frequently seen in the patients seeking orthodontic treatment. The treatment goal of detaching the midpalatal suture can be achieved using an expansion device. In present article we give a review on various palatal expansion appliances and treatment protocol. A comprehensive search of the literatures was performed to observe the regime of different maxillary expansion appliances and therapies.

  19. Flow in axisymmetric expansion in a catalytic converter

    OpenAIRE

    Gotfredsen, Erik; Meyer, Knud Erik

    2017-01-01

    The flow in an axisymmetric expansion (circular diffusor) is used in many different engineering applications, such as heat exchangers, catalytic converters and filters. These applications require a relatively uniform flow at the inlet. To minimise the pressure loss, an ideal solution would be to use a quite long expansion, but this is often not possible due to space restrictions. Therefore a short expansion combined with e.g. guide vanes is often used. The present study will use a Selective C...

  20. Series expansions of rotating two and three dimensional sound fields.

    Science.gov (United States)

    Poletti, M A

    2010-12-01

    The cylindrical and spherical harmonic expansions of oscillating sound fields rotating at a constant rate are derived. These expansions are a generalized form of the stationary sound field expansions. The derivations are based on the representation of interior and exterior sound fields using the simple source approach and determination of the simple source solutions with uniform rotation. Numerical simulations of rotating sound fields are presented to verify the theory.

  1. Does query expansion limit our learning? A comparison of social-based expansion to content-based expansion for medical queries on the internet.

    Science.gov (United States)

    Pentoney, Christopher; Harwell, Jeff; Leroy, Gondy

    2014-01-01

    Searching for medical information online is a common activity. While it has been shown that forming good queries is difficult, Google's query suggestion tool, a type of query expansion, aims to facilitate query formation. However, it is unknown how this expansion, which is based on what others searched for, affects the information gathering of the online community. To measure the impact of social-based query expansion, this study compared it with content-based expansion, i.e., what is really in the text. We used 138,906 medical queries from the AOL User Session Collection and expanded them using Google's Autocomplete method (social-based) and the content of the Google Web Corpus (content-based). We evaluated the specificity and ambiguity of the expansion terms for trigram queries. We also looked at the impact on the actual results using domain diversity and expansion edit distance. Results showed that the social-based method provided more precise expansion terms as well as terms that were less ambiguous. Expanded queries do not differ significantly in diversity when expanded using the social-based method (6.72 different domains returned in the first ten results, on average) vs. content-based method (6.73 different domains, on average).

  2. Expansion ortopedica maxilar con ortodoncia osteogenica periodontalmente acelerada

    National Research Council Canada - National Science Library

    Lopez Buitrago, Diego Fernando; Jaramillo Abadia, Isabel Cristina

    2014-01-01

    .... Historicamente, el tratamiento de la discrepancia esqueletica transversal ha estado acompanado de procedimientos de cirugia ortognatica que separan las suturas para permitir la expansion mediante...

  3. Expansion of Tubular with Elastomers in Multilateral Wells

    Directory of Open Access Journals (Sweden)

    Md Velden

    2013-06-01

    Full Text Available The use of solid expandable tubular technology during the last decade has focused on solving many challenges in well drilling and delivery including zonal isolation, deep drilling, conservation of hole sizes, etc. not only as pioneered solution but also providing cost effective and long lasting solutions. Concurrently, the technology was extended for construction of multilateral in typical wells. The process of horizontal tubular expansion is similar to the vertical expansion of expandable tubular in down-hole environment with the addition of uniformly distributed force due to its weight. The expansion is targeted to increase its diameter such that post expansion characteristics remain within allowable limits. In this study a typical expandable tubular of 57.15 mm outer diameter and 6.35 mm wall thickness was used with two different elastomer seals of 5 and 7 mm thickness placed at equal spacing of 200 mm. The developed stress contours during expansion process clearly showed the high stress areas in the vicinity of expansion region which lies around the mandrel. These high stresses may result in excessive wear of the mandrel. It was also found out that the drawing force increases as the mandrel angle, expansion ratio, and friction coefficient increases. A mandrel angle of 20o  requires minimum expansion force and can be considered as an optimum geometrical parameter to lower the power required for expansion.

  4. 3D automatic expansion: clinical application; L`expansion 3D automatique: application clinique

    Energy Technology Data Exchange (ETDEWEB)

    Gaboriaud, G.; Pontvert, D.; Rosenwald, J.C. [Institut Curie, 75 - Paris (France)

    1998-09-01

    The determination of the various volumes (GTV: gross target volume, CTV: clinical target volume, PTV: planned target volume) recommended by the ICRU 50 report is a critical step in conformal treatment planning, since treatment optimisation procedures and documentation rely on accurate dose-volume histograms. The shape and the size of the CTV vary with the computer algorithm, the patient image acquisition parameters, the definition of the GTV and the margins surrounding it. The automatic expansion programs included in commercially available treatment planning system require careful validation and control before and during their routine use by the clinicians. Significant differences have been observed between 2D- and 3D-based expansions, with a usual underestimation of the PTV by 2D algorithms. (author)

  5. Human expansion precipitates niche expansion for an opportunistic apex predator (Puma concolor).

    Science.gov (United States)

    Moss, Wynne E; Alldredge, Mathew W; Logan, Kenneth A; Pauli, Jonathan N

    2016-12-23

    There is growing recognition that developed landscapes are important systems in which to promote ecological complexity and conservation. Yet, little is known about processes regulating these novel ecosystems, or behaviours employed by species adapting to them. We evaluated the isotopic niche of an apex carnivore, the cougar (Puma concolor), over broad spatiotemporal scales and in a region characterized by rapid landscape change. We detected a shift in resource use, from near complete specialization on native herbivores in wildlands to greater use of exotic and invasive species by cougars in contemporary urban interfaces. We show that 25 years ago, cougars inhabiting these same urban interfaces possessed diets that were intermediate. Thus, niche expansion followed human expansion over both time and space, indicating that an important top predator is interacting with prey in novel ways. Thus, though human-dominated landscapes can provide sufficient resources for apex carnivores, they do not necessarily preserve their ecological relationships.

  6. Theology and development as capability expansion

    Directory of Open Access Journals (Sweden)

    Séverine Deneulin

    2016-05-01

    Full Text Available For the last 25 years, human development has become part of official development discourses. It takes the normative position that the success of policies depends on whether they have expanded human flourishing, or expanded the ‘freedoms’ or ‘capabilities’ people have ‘reason to value’, as Amartya Sen would put it. It emphasises the importance of institutions to facilitate such expansion, and the agency of people to create such institutions. The ability of institutions to be conducive to human flourishing depends on the nature of human interaction. When human interaction no longer has the flourishing of other persons as its aim, it can create structures which then constrain human agency. The article argues that the human development perspective could be enriched by theological insights such as structural sin and the contribution of religious narratives to public reasoning. It concentrates on the idea of justice of one biblical parable, and illustrates its argument with examples from the Argentine labour context.

  7. The optimizied expansion method for wavefield extrapolation

    KAUST Repository

    Wu, Zedong

    2013-01-01

    Spectral methods are fast becoming an indispensable tool for wave-field extrapolation, especially in anisotropic media, because of its dispersion and artifact free, as well as highly accurate, solutions of the wave equation. However, for inhomogeneous media, we face difficulties in dealing with the mixed space-wavenumber domain operator.In this abstract, we propose an optimized expansion method that can approximate this operator with its low rank representation. The rank defines the number of inverse FFT required per time extrapolation step, and thus, a lower rank admits faster extrapolations. The method uses optimization instead of matrix decomposition to find the optimal wavenumbers and velocities needed to approximate the full operator with its low rank representation.Thus,we obtain more accurate wave-fields using lower rank representation, and thus cheaper extrapolations. The optimization operation to define the low rank representation depends only on the velocity model, and this is done only once, and valid for a full reverse time migration (many shots) or one iteration of full waveform inversion. Applications on the BP model yielded superior results than those obtained using the decomposition approach. For transversely isotopic media, the solutions were free of the shear wave artifacts, and does not require that eta>0.

  8. Technology portfolio and capacity expansion under uncertainty

    Science.gov (United States)

    Filomena, Tiago Pascoal

    We analyze the problem of generation capacity expansion and portfolio of technologies choice in a restructured electricity market in which marginal costs are uncertain. In our investment model, firms behave as Cournot players and they make three different decisions in equilibrium: (i) the portfolio of technologies, (ii) technologies capacity and (iii) technologies production for every scenario. The decisions related to the portfolio and capacity are ex-ante and the production is ex-post to the realization of uncertainty. We consider the marginal cost as the uncertain parameter and we show with a simple transformation that the model is also flexible to allow for general load curves. Our main result is that portfolio diversification arises even with risk-neutral firms and technologies with different cost expectations. Furthermore, we characterize the production level of each firm for each possible scenario realization. All the conditions that yield (or do not yield) to diversification in a duopoly with two scenarios are discussed in the dissertation. Under our assumptions, we point out that in aggregate terms firms always invest and produce the same quantities. Asymmetry on the use of technologies between players can occur, but it just happens when technologies have the same cost expectation. We show that when technologies present different cost expectation the equilibrium results are unique and symmetric.

  9. Survivial Strategies in Bacterial Range Expansions

    Science.gov (United States)

    Frey, Erwin

    2014-03-01

    Bacterial communities represent complex and dynamic ecological systems. Different environmental conditions as well as bacterial interactions determine the establishment and sustainability of bacterial diversity. In this talk we discuss the competition of three Escherichia coli strains during range expansions on agar plates. In this bacterial model system, a colicin E2 producing strain C competes with a colicin resistant strain R and with a colicin sensitive strain S for new territory. Genetic engineering allows us to tune the growth rates of the strains and to study distinct ecological scenarios. These scenarios may lead to either single-strain dominance, pairwise coexistence, or to the coexistence of all three strains. In order to elucidate the survival mechanisms of the individual strains, we also developed a stochastic agent-based model to capture the ecological scenarios in silico. In a combined theoretical and experimental approach we are able to show that the level of biodiversity depends crucially on the composition of the inoculum, on the relative growth rates of the three strains, and on the effective reach of colicin toxicity.

  10. Medicaid Expansion: A Tale of Two Governors.

    Science.gov (United States)

    Flagg, Robin

    2016-10-01

    This is a study of why two seemingly similar governors made divergent decisions on expanding Medicaid under the Patient Protection and Affordable Care Act (ACA). Performing a case study of Governors John Kasich (OH) and Scott Walker (WI), I explore the roles played by electoral pressures, political party, governor's ideology, the state's policy heritage, stakeholder advocacy, and the economy in each governor's decision about whether to expand Medicaid. Electoral pressure was the most significant factor for both governors. I demonstrate that even Walker succumbed to state electoral pressures and expanded Medicaid, albeit in a manner unique to Wisconsin. He did this despite his emphatic national rhetoric rejecting Obamacare and expansion. Additionally, existing state political institutions drove each governor to decide in a manner unique to his state: previous Medicaid decisions in Wisconsin and direct democracy in Ohio provided additional pressures and divergent starting points. The remaining factors served less as a driving force behind the decision and more as a frame to justify the decision ex post facto. Case studies allow for a more complex view of how political pressures fit together; differences can be explained and expanded, and an enhanced understanding of political processes can be gleaned. Copyright © 2016 by Duke University Press.

  11. Semiquantum chaos and the large N expansion

    Energy Technology Data Exchange (ETDEWEB)

    Cooper, F.; Habib, S.; Kluger, Y. [Los Alamos National Lab., NM (United States); Dawson, J.; Meredith, D.; Shepard, H. [New Hampshire Univ., Durham, NH (United States). Dept. of Physics

    1994-06-29

    When a classical oscillator is interacting with a purely quantum mechanical oscillator, described by the Lagrangian L = 1/2 x{sup 2} + 1/2A{sup 2} - 1/2 (m{sup 2} + e{sup 2} A{sup 2})x{sup 2}, where A is a classical variable and x is a quantum operator the relevant degrees of freedom for the quantum oscillator when {l_angle}x(t)x(t){r_angle} = G(t). The classical Hamiltonian dynamics governing the variables A(t). {Pi}{sub A}(t). G(t) and {Pi}{sub G}(t) is chaotic so that the results of making measurements on the quantum system at later times are sensitive to initial conditions. We review this system and discuss how this behavior is altered when the quantum fluctuations of the A oscillator are determined exactly and in a 1/N expansion where N is the number of copies of the x oscillator.

  12. [Feedback control mechanisms of plant cell expansion

    Energy Technology Data Exchange (ETDEWEB)

    Cosgrove, D.J.

    1992-01-01

    We have generated considerable evidence for the significance of wall stress relaxation in the control of plant growth and found that several agents (gibberellin, light, genetic loci for dwarf stature) influence growth rate via alteration of wall relaxation. We have refined our methods for measuring wall relaxation and, moreover, have found that wall relaxation properties bear only a distance relationship to wall mechanical properties. We have garnered novel insights into the nature of cell expansion mechanisms by analyzing spontaneous fluctuations of plant growth rate in seedlings. These experiments involved the application of mathematical techniques for analyzing growth rate fluctuations and the development of new instrumentation for measuring and forcing plant growth in a controlled fashion. These studies conclude that growth rate fluctuations generated by the plant as consequence of a feedback control system. This conclusion has important implications for the nature of wall loosening processes and demands a different framework for thinking about growth control. It also implies the existence of a growth rate sensor.

  13. Progesterone induces adult mammary stem cell expansion.

    Science.gov (United States)

    Joshi, Purna A; Jackson, Hartland W; Beristain, Alexander G; Di Grappa, Marco A; Mote, Patricia A; Clarke, Christine L; Stingl, John; Waterhouse, Paul D; Khokha, Rama

    2010-06-10

    Reproductive history is the strongest risk factor for breast cancer after age, genetics and breast density. Increased breast cancer risk is entwined with a greater number of ovarian hormone-dependent reproductive cycles, yet the basis for this predisposition is unknown. Mammary stem cells (MaSCs) are located within a specialized niche in the basal epithelial compartment that is under local and systemic regulation. The emerging role of MaSCs in cancer initiation warrants the study of ovarian hormones in MaSC homeostasis. Here we show that the MaSC pool increases 14-fold during maximal progesterone levels at the luteal dioestrus phase of the mouse. Stem-cell-enriched CD49fhi cells amplify at dioestrus, or with exogenous progesterone, demonstrating a key role for progesterone in propelling this expansion. In aged mice, CD49fhi cells display stasis upon cessation of the reproductive cycle. Progesterone drives a series of events where luminal cells probably provide Wnt4 and RANKL signals to basal cells which in turn respond by upregulating their cognate receptors, transcriptional targets and cell cycle markers. Our findings uncover a dynamic role for progesterone in activating adult MaSCs within the mammary stem cell niche during the reproductive cycle, where MaSCs are putative targets for cell transformation events leading to breast cancer.

  14. Testing option pricing with the Edgeworth expansion

    Science.gov (United States)

    Balieiro Filho, Ruy Gabriel; Rosenfeld, Rogerio

    2004-12-01

    There is a well-developed framework, the Black-Scholes theory, for the pricing of contracts based on the future prices of certain assets, called options. This theory assumes that the probability distribution of the returns of the underlying asset is a Gaussian distribution. However, it is observed in the market that this hypothesis is flawed, leading to the introduction of a fudge factor, the so-called volatility smile. Therefore, it would be interesting to explore extensions of the Black-Scholes theory to non-Gaussian distributions. In this paper, we provide an explicit formula for the price of an option when the distributions of the returns of the underlying asset is parametrized by an Edgeworth expansion, which allows for the introduction of higher independent moments of the probability distribution, namely skewness and kurtosis. We test our formula with options in the Brazilian and American markets, showing that the volatility smile can be reduced. We also check whether our approach leads to more efficient hedging strategies of these instruments.

  15. Can snowshoe hares control treeline expansions?

    Science.gov (United States)

    Olnes, Justin; Kielland, Knut; Juday, Glenn P; Mann, Daniel H; Genet, Hélène; Ruess, Roger W

    2017-10-01

    Treelines in Alaska are advancing in elevation and latitude because of climate warming, which is expanding the habitat available for boreal wildlife species, including snowshoe hares (Lepus americanus). Snowshoe hares are already present in tall shrub communities beyond treeline and are the main browser of white spruce (Picea glauca), the dominant tree species at treeline in Alaska. We investigated the processes involved in a "snowshoe hare filter" to white spruce establishment near treeline in Denali National Park, Alaska, USA. We modeled the pattern of spruce establishment from 1970 to 2009 and found that fewer spruce established during periods of high hare abundance. Multiple factors interact to influence browsing of spruce, including the hare cycle, snow depth and the characteristics of surrounding vegetation. Hares are abundant at treeline and may exclude spruce from otherwise optimal establishment sites, particularly floodplain locations with closed shrub canopies. The expansion of white spruce treeline in response to warming climate will be strongly modified by the spatial and temporal dynamics of the snowshoe hare filter. © 2017 by the Ecological Society of America.

  16. Oil sector expansion hits small road bump

    Energy Technology Data Exchange (ETDEWEB)

    Budd, G.

    2002-04-01

    Indications are that the upward production trend in Saskatchewan's oil industry, evident in recent years, will be reversed in 2002. Predictions are that the drop in production will be a modest one, reflecting the slower economy and the lag time between drilling activity and produced barrels of oil. Also a contributing factor is the fact that the year 2001 marked a decline of 20 per cent in oil well drilling from the previous year, down from 2,401 wells drilled to 1,931 wells. Expansions of last year such as PanCanadian's carbon dioxide project, Husky Energy's heavy oil project at Pike's Peak, northeast of Lloydminster, PanCanadian's SAGD project, Conoco's project at the Kerrobert Pool and Apache Canada's Midale area project southeast of Regina, are all likely to see more modest development during 2002. Similar retrenchment is expected at Nexen's (Wascana) Williston Basin area operations, due in part to the increased drilling cost resulting from the intense activity during 2001, and a 5 to 10 per cent rise in operating costs.

  17. Modeling the expansion of a contactor plasma

    Science.gov (United States)

    Hogan, E. A.; Delzanno, G.; Camporeale, E.; Borovsky, J. E.; MacDonald, E.; Thomsen, M. F.

    2012-12-01

    Plasma contactor technology is widely used on board spacecraft to keep spacecraft charging levels under control. On the International Space Station, for instance, it is used to prevent high current discharges between differently charged surfaces. It consists of emitting a neutral plasma to create a plasma reservoir near the spacecraft in order to balance the currents collected by the spacecraft from the magnetospheric environment. One approach to modeling the contactor plasma plume applies a self-similar solution in order to gain insight into the plume dynamics without requiring expensive numerical simulations [1, 2]. Typically, hydrodynamic fluid equations are used to model the plasma behavior. We present a comparison of different self-similar plume models existing in the literature [1, 2] and compare these with our Particle-In-Cell simulations in the near-field to assess their validity. We will consider both the unmagnetized and the magnetized limit, treating the magnitude and angle (relative to the plasma injection velocity) of the magnetic field as a parameter. [1] F. F. Gabdullin, A. G. Korsun, E. M. Tverdokhlebova, 'The plasma plume emitted onboard the international space station under the effect of the geomagnetic field', IEEE Trans. Plasma Science 36(5) 2207 (2008). [2] M. Merino, E. Ahedo, C. Bombardelli, H. Urrutxua, J. Pelaez, 'Hypersonic plasma plume expansion in space', 32nd International Electric Propulsion Conference, IEPC-2011-086, Wiesbaden, Germany, 2011.

  18. Harmonious Expansion of China's Higher Education: A New Growth Pattern

    Science.gov (United States)

    Gu, Jiafeng

    2012-01-01

    How can one country narrow the regional disparity during the tremendous expansion of higher education? This issue remains unexamined and critical analysis is needed to unveil the spatial dynamics behind expansion of higher education. The spatial analysis shows that there is significant strategic interaction among neighboring provinces in China…

  19. Analysis of Factors Influencing Agritourism Businesses in Expansion

    OpenAIRE

    Jensen, Kimberly; Bruch Leffew, Megan; Menard, Jamey; English, Burton C.

    2014-01-01

    This study assesses how characteristics of agritourism operations may influence future expansion plans. Differences in barriers which agritourism operations face, as well as types of promotion methods used are examined for expansion-minded agritourism operators. This information will be useful to agritourism operators, as they look for contributors to future growth.

  20. STABILIZATION OF EXPANSIVE SOIL USING BAGASSE ASH & LIME

    African Journals Online (AJOL)

    tekimerry

    (MDD) and plasticity of the soil for all additives. But there was also a tremendous improvement in the CBR value when the soil is stabilized with a combination of lime and bagasse ash. This shows a potential of using bagasse ash as admixture in lime stabilized expansive soil. Keywords: Expansive soil, bagasse ash, lime,.

  1. Impact of size and temperature on thermal expansion of nanomaterials

    Indian Academy of Sciences (India)

    A theoretical method has been discussed to study the size dependency of thermal expansion of nanomaterials at higher temperature by considering the surface effect. A thermodynamical analysis of the equation of state (EoS) is studied from the knowledge of thermal expansion of nano-materials based on theoretical ...

  2. Did the Higgs boson drive the universe's expansion?

    CERN Multimedia

    2008-01-01

    The Higgs boson has been moonlighting. Not content with its day job of giving other particles their mass, it may also have driven the expansion of the early universe, given a little tinkering, according to two separate studies. Soon after the big bang the early universe is believed to have undergone a period of rapid expansion, known as inflation.

  3. Implementation of centrifuge testing of expansive soils for pavement design.

    Science.gov (United States)

    2017-03-01

    The novel centrifuge-based method for testing of expansive soils from project 5-6048-01 was implemented into : use for the determination of the Potential Vertical Rise (PVR) of roadways that sit on expansive subgrades. The : centrifuge method was mod...

  4. Studies of Expansive Learning: Foundations, Findings and Future Challenges

    Directory of Open Access Journals (Sweden)

    Yrjö Engeström

    2013-07-01

    Full Text Available The paper examines studies based on the theory of expansive learning, formulated in 1987. In recent years the theory has been used in a wide variety of studies and interventions. The theory builds on foundational ideas put forward by Vygotsky, Leont’ev, Il’enkov, and Davydov, key figures in the Russian school of cultural-historical activity theory. Studies based on the theory are reviewed in six sections: expansive learning as transformation of the object, expansive learning as movement in the zone of proximal development, expansive learning as cycles of learning actions, expansive learning as boundary crossing and network building, expansive learning as distributed and discontinuous movement, and formative interventions.A separate section is devoted to critiques of expansive learning. It is concluded that the ultimate test of learning theories is how they help practitioners to generate learning that grasps pressing issues the humankind is facing. The theory of expansive learning currently expands its analyses both up and down, outward and inward. Moving up and outward, it tackles learning in fields or networks of interconnected activity systems with their partially shared and often contested objects. Moving down and inward, it tackles issues of subjectivity, experiencing, personal sense, emotion, embodiment, identity, and moral commitment.

  5. Clusters of Organic Molecules in a Supersonic Jet Expansion

    NARCIS (Netherlands)

    Jonkman, Harry T.; Even, Uzi; Kommandeur, Jan

    1985-01-01

    A wide variety of clusters were obtained in seeded supersonic conical jet expansions of organic molecules. It was shown that mixed clusters probably are formed statistically in the collisional region of the expansion, although kinetic effects cannot be excluded. The molecular fragmentation in the

  6. Shrub expansion in SW Greenland under modest regional warming

    DEFF Research Database (Denmark)

    Jørgensen, Rasmus Halfdan; Meilby, Henrik; Kollmann, Johannes

    2013-01-01

    Shrub expansion has been observed widely in tundra areas across the Arctic. This phenomenon has been partially attributed to increasing temperatures over the past century. However, relationships among shrub expansion, grazing, and human disturbance have been studied little. SW Greenland is a suba...

  7. Dynamics of plasma expansion in the pulsed laser material interaction

    Indian Academy of Sciences (India)

    process results from the anisotropic expansion velocities associated with different species. These velocities are mainly controlled by the initial dimension of the expanding plasma. An attempt was undertaken to estimate the length of the plume at different ambient gas pressures using an adiabatic expansion model. The rate.

  8. Surgical Splint Design Influences Transverse Expansion in Segmental Maxillary Osteotomies

    DEFF Research Database (Denmark)

    Stokbro, Kasper; Aagaard, Esben; Torkov, Peter

    2017-01-01

    Purpose: In segmental maxillary procedures, it is imperative to obtain as much of the planned expansion as possible. Lack of obtained expansion, in addition to late relapse after splint removal, can result in relapse of the posterior crossbite. This study investigated the influence of 2 surgical ...

  9. Expansion of U. S. uranium enrichment capacity. Final environmental statement

    Energy Technology Data Exchange (ETDEWEB)

    1976-04-01

    Reasonably foreseeable environmental, social, economic, and technological costs and benefits of postulated expansion of U. S. enrichment capacity through the year 2000 and reasonably available alternatives to such expansion are described. Both the gas centrifuge and gaseous diffusion methods for the enrichment of uranium are considered in this impact assessment. (JGB)

  10. 1 INVESTIGATIONS ON THE EXPANSIVE SOILS OF ADDIS ABABA ...

    African Journals Online (AJOL)

    group comprises of basic igneous rocks. Here feldspar and pyroxene minerals of the parent rocks decompose to form montmorillonite - the predominant mineral of expansive soil - and other secondary minerals. The second group comprises of sedimentary rocks that contain montmorillonite. The expansive soils of Ethiopia ...

  11. Higher Education in Ethiopia: Expansion, Quality Assurance and Institutional Autonomy

    Science.gov (United States)

    Akalu, Girmaw Abebe

    2014-01-01

    This article chronicles the key challenges facing Ethiopia as it embarks on an ambitious, ideologically-driven and aggressive expansion of its higher education system in an effort to address its national goals of economic growth and poverty reduction. It is argued that the urge for higher education expansion has placed undue pressures particularly…

  12. 12 CFR 34.84 - Future bank expansion.

    Science.gov (United States)

    2010-01-01

    ... 12 Banks and Banking 1 2010-01-01 2010-01-01 false Future bank expansion. 34.84 Section 34.84 Banks and Banking COMPTROLLER OF THE CURRENCY, DEPARTMENT OF THE TREASURY REAL ESTATE LENDING AND APPRAISALS Other Real Estate Owned § 34.84 Future bank expansion. A national bank normally should use real...

  13. Asymptotic expansions for high-contrast linear elasticity

    KAUST Repository

    Poveda, Leonardo A.

    2015-03-01

    We study linear elasticity problems with high contrast in the coefficients using asymptotic limits recently introduced. We derive an asymptotic expansion to solve heterogeneous elasticity problems in terms of the contrast in the coefficients. We study the convergence of the expansion in the H1 norm. © 2015 Elsevier B.V.

  14. 14 CFR 29.969 - Fuel tank expansion space.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Fuel tank expansion space. 29.969 Section 29.969 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Powerplant Fuel System § 29.969 Fuel tank expansion space...

  15. 14 CFR 27.969 - Fuel tank expansion space.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Fuel tank expansion space. 27.969 Section 27.969 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: NORMAL CATEGORY ROTORCRAFT Powerplant Fuel System § 27.969 Fuel tank expansion space...

  16. 14 CFR 25.969 - Fuel tank expansion space.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Fuel tank expansion space. 25.969 Section 25.969 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Powerplant Fuel System § 25.969 Fuel tank expansion space...

  17. Electric Grid Expansion Planning with High Levels of Variable Generation

    Energy Technology Data Exchange (ETDEWEB)

    Hadley, Stanton W. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); You, Shutang [Univ. of Tennessee, Knoxville, TN (United States); Shankar, Mallikarjun [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Liu, Yilu [Univ. of Tennessee, Knoxville, TN (United States); Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2016-02-01

    Renewables are taking a large proportion of generation capacity in U.S. power grids. As their randomness has increasing influence on power system operation, it is necessary to consider their impact on system expansion planning. To this end, this project studies the generation and transmission expansion co-optimization problem of the US Eastern Interconnection (EI) power grid with a high wind power penetration rate. In this project, the generation and transmission expansion problem for the EI system is modeled as a mixed-integer programming (MIP) problem. This study analyzed a time series creation method to capture the diversity of load and wind power across balancing regions in the EI system. The obtained time series can be easily introduced into the MIP co-optimization problem and then solved robustly through available MIP solvers. Simulation results show that the proposed time series generation method and the expansion co-optimization model and can improve the expansion result significantly after considering the diversity of wind and load across EI regions. The improved expansion plan that combines generation and transmission will aid system planners and policy makers to maximize the social welfare. This study shows that modelling load and wind variations and diversities across balancing regions will produce significantly different expansion result compared with former studies. For example, if wind is modeled in more details (by increasing the number of wind output levels) so that more wind blocks are considered in expansion planning, transmission expansion will be larger and the expansion timing will be earlier. Regarding generation expansion, more wind scenarios will slightly reduce wind generation expansion in the EI system and increase the expansion of other generation such as gas. Also, adopting detailed wind scenarios will reveal that it may be uneconomic to expand transmission networks for transmitting a large amount of wind power through a long distance

  18. Micro-architected Composite Lattices with Tunable Negative Thermal Expansions

    Science.gov (United States)

    Wang, Qiming

    Solid materials with minimum or negative thermal expansion (NTE) have broad applications, from dental fillings to thermal-sensitive precision instruments. Previous studies on NTE structures were mostly focused on theoretically design and 2D experimental demonstrations. Here, aided with multimaterial projection micro-stereolithography, we experimentally fabricate multi-material composite lattices that exhibit significant negative thermal expansion in three directions and over a large range of temperature variations. The negative thermal expansion is induced by the structural interaction of material components with distinct thermal expansion coefficients. The NTE performance can be tuned over a large range by varying the thermal expansion coefficient difference between constituent beams and geometrical arrangement. Our experimental results match qualitatively with a simple scaling law and quantitatively consistently with computational models.

  19. Bubble motion in sudden expansion in vertical pipe flow

    Energy Technology Data Exchange (ETDEWEB)

    Kondo, Koichi [Marine Technical College, Ashiya, Hyogo (Japan); Yoshida, Kenji; Matsumoto, Tadayoshi; Okawa, Tomio; Kataoka, Isao [Osaka Univ., Suita, Osaka (Japan)

    2002-07-01

    Experimental studies were made on the multi-dimensional behavior of upward gas-liquid two-phase flow through the vertical round tube with an axisymmetric sudden expansion, which is one of the typical multi-dimensional channel geometry. The direct observation using high-speed video camera was performed and revealed the multi-dimensional dynamic flow behavior affected by the sudden expansion. Characteristic phenomena were observed such as bubble break-up, deformation due to the strong share of liquid flow, or liquid micro jet penetration through the gas-slug, and so on. From these results, the flow regime map at the below or above of the sudden expansion part was classified. The phase distributions in sudden expansion were also showed in detail that how the two-phase flow develops along the direction of the downstream of the sudden expansion. (J.P.N.)

  20. Assessing thesaurus-based query expansion using the UMLS Metathesaurus.

    Science.gov (United States)

    Hersh, W; Price, S; Donohoe, L

    2000-01-01

    Assess query expansion using thesaurus relationships and definitions in the UMLS Metathesaurus for improving searching performance. The queries from a MEDLINE test collection (OHSUMED) were expanded using synonym, hierarchical, and related term information as well as term definitions from the UMLS Metathesaurus. Documents were retrieved from a word-statistical retrieval system and assessed for recall and precision based on relevance judgments from the test collection. All types of query expansion degraded aggregate retrieval performance as measured by recall and precision, although 38.6% of the queries with synonym expansion and up to 29.7% of the queries with hierarchical expansion showed improvement. Thesaurus-based query expansion causes a decline in retrieval performance generally but improves it in specific instances. Further research must focus on identifying instances where performance improves and how it can be exploited by real users.

  1. A Meta-Analysis of Global Urban Land Expansion

    Science.gov (United States)

    Seto, Karen C.; Fragkias, Michail; Güneralp, Burak; Reilly, Michael K.

    2011-01-01

    The conversion of Earth's land surface to urban uses is one of the most irreversible human impacts on the global biosphere. It drives the loss of farmland, affects local climate, fragments habitats, and threatens biodiversity. Here we present a meta-analysis of 326 studies that have used remotely sensed images to map urban land conversion. We report a worldwide observed increase in urban land area of 58,000 km2 from 1970 to 2000. India, China, and Africa have experienced the highest rates of urban land expansion, and the largest change in total urban extent has occurred in North America. Across all regions and for all three decades, urban land expansion rates are higher than or equal to urban population growth rates, suggesting that urban growth is becoming more expansive than compact. Annual growth in GDP per capita drives approximately half of the observed urban land expansion in China but only moderately affects urban expansion in India and Africa, where urban land expansion is driven more by urban population growth. In high income countries, rates of urban land expansion are slower and increasingly related to GDP growth. However, in North America, population growth contributes more to urban expansion than it does in Europe. Much of the observed variation in urban expansion was not captured by either population, GDP, or other variables in the model. This suggests that contemporary urban expansion is related to a variety of factors difficult to observe comprehensively at the global level, including international capital flows, the informal economy, land use policy, and generalized transport costs. Using the results from the global model, we develop forecasts for new urban land cover using SRES Scenarios. Our results show that by 2030, global urban land cover will increase between 430,000 km2 and 12,568,000 km2, with an estimate of 1,527,000 km2 more likely. PMID:21876770

  2. 78 FR 2952 - Foreign-Trade Zone 3-San Francisco, California; Application for Expansion and Expansion of...

    Science.gov (United States)

    2013-01-15

    ... Foreign-Trade Zones Board Foreign-Trade Zone 3--San Francisco, California; Application for Expansion and Expansion of Service Area Under Alternative Site Framework An application has been submitted to the Foreign..., 10/20/2010). The zone project currently has a service area that includes the City and County of San...

  3. Myocardial infarct expansion, infarct extension, and reinfarction: pathophysiologic concepts.

    Science.gov (United States)

    Weisman, H F; Healy, B

    1987-01-01

    Infarct expansion and infarct extension are events early in the course of myocardial infarction with serious short- and long-term consequences. Infarct expansion, disproportionate thinning, and dilatation of the infarct segment probably begin within hours of acute infarction and usually reach peak extent within seven to 14 days. Clinical data suggest that infarct expansion occurs in approximately 35% to 45% of anterior transmural myocardial infarctions and to a lesser extent in infarctions at other sites. Although expansion usually develops in large infarcts, the extent of transmural necrosis rather than absolute infarct size predicts its occurrence. Expansion has an adverse effect on infarct structure and function for several reasons. Functional infarct size is increased because of infarct segment lengthening, and expansion results in over-all ventricular dilatation. Thus, patients with expansion of an infarct have poorer exercise tolerance, more congestive heart failure symptoms, and greater early and late mortality than those without expansion. Infarct rupture and late aneurysm formation are two additional structural consequences of infarct expansion. Experimental and clinical data suggest that the incidence and severity of expansion can be modified by interventions. Increased ventricular loading conditions and steroidal and nonsteroidal antiinflammatory agents make expansion more severe. Reperfusion of the infarct segment and pharmacologic interventions that decrease ventricular afterload lessen the severity of expansion. Previous myocardial infarction and preexisting ventricular hypertrophy may also limit the development of infarct expansion. Infarct extension is defined clinically as early in-hospital reinfarction after a myocardial infarction. The pathologic finding of infarct extension is necrotic and healing myocardium of several different recent ages within the same vascular territory. Although this pathologic criterion usually cannot be verified, studies

  4. Future urban land expansion and implications for global croplands.

    Science.gov (United States)

    Bren d'Amour, Christopher; Reitsma, Femke; Baiocchi, Giovanni; Barthel, Stephan; Güneralp, Burak; Erb, Karl-Heinz; Haberl, Helmut; Creutzig, Felix; Seto, Karen C

    2017-08-22

    Urban expansion often occurs on croplands. However, there is little scientific understanding of how global patterns of future urban expansion will affect the world's cultivated areas. Here, we combine spatially explicit projections of urban expansion with datasets on global croplands and crop yields. Our results show that urban expansion will result in a 1.8-2.4% loss of global croplands by 2030, with substantial regional disparities. About 80% of global cropland loss from urban expansion will take place in Asia and Africa. In both Asia and Africa, much of the cropland that will be lost is more than twice as productive as national averages. Asia will experience the highest absolute loss in cropland, whereas African countries will experience the highest percentage loss of cropland. Globally, the croplands that are likely to be lost were responsible for 3-4% of worldwide crop production in 2000. Urban expansion is expected to take place on cropland that is 1.77 times more productive than the global average. The loss of cropland is likely to be accompanied by other sustainability risks and threatens livelihoods, with diverging characteristics for different megaurban regions. Governance of urban area expansion thus emerges as a key area for securing livelihoods in the agrarian economies of the Global South.

  5. Effect of rapid maxillary expansion on sleep characteristics in children

    Directory of Open Access Journals (Sweden)

    Navya Ashok

    2014-01-01

    Full Text Available Introduction: Rapid maxillary expansion (RME is an orthopedic treatment procedure routinely used to treat constricted maxillary arches and also a potential additional treatment in children presenting with sleep-disordered breathing (SDB. Aims and Objectives: The main objective of this study was to evaluate the effects of RME on sleep characteristics in children. Materials and Methods: Polysomnography was done on children of 8-13 years of age before expansion (T0, after expansion (T1 and after a period of 3 months after retention (T2. Bonded rapid maxillary expander was cemented in all children. Inter-molar distance was also measured at T0 and T2. Statistical Analysis: Nonparametric Friedman test was used for comparing the averages of sleep parameters at different time period (T0, T1, T2. Wilcoxon signed ranks test was used for comparing the averages of inter-molar width (T0-T2. P < 0.05 were considered as significant. Results: All children showed an improvement in sleep parameters with an increase in sleep efficiency, decreased in arousal and desaturation index after expansion. Total sleep time showed a statistically significant increase after expansion. A statistically significant increase in inter-molar distance was obtained after expansion. Conclusions: Rapid maxillary expansion is a useful treatment option for improving quality of sleep even in normal children without SDB. It also induces widening of the maxilla, corrects posterior crossbites and improves maxillary and mandibular dental arch coordination.

  6. Effect of rapid maxillary expansion on sleep characteristics in children.

    Science.gov (United States)

    Ashok, Navya; Varma, N K Sapna; Ajith, V V; Gopinath, Siby

    2014-10-01

    Rapid maxillary expansion (RME) is an orthopedic treatment procedure routinely used to treat constricted maxillary arches and also a potential additional treatment in children presenting with sleep-disordered breathing (SDB). The main objective of this study was to evaluate the effects of RME on sleep characteristics in children. Polysomnography was done on children of 8-13 years of age before expansion (T0), after expansion (T1) and after a period of 3 months after retention (T2). Bonded rapid maxillary expander was cemented in all children. Inter-molar distance was also measured at T0 and T2. Nonparametric Friedman test was used for comparing the averages of sleep parameters at different time period (T0, T1, T2). Wilcoxon signed ranks test was used for comparing the averages of inter-molar width (T0-T2). P children showed an improvement in sleep parameters with an increase in sleep efficiency, decreased in arousal and desaturation index after expansion. Total sleep time showed a statistically significant increase after expansion. A statistically significant increase in inter-molar distance was obtained after expansion. Rapid maxillary expansion is a useful treatment option for improving quality of sleep even in normal children without SDB. It also induces widening of the maxilla, corrects posterior crossbites and improves maxillary and mandibular dental arch coordination.

  7. Controlling Thermal Expansion: A Metal–Organic Frameworks Route

    Science.gov (United States)

    2016-01-01

    Controlling thermal expansion is an important, not yet resolved, and challenging problem in materials research. A conceptual design is introduced here, for the first time, for the use of metal–organic frameworks (MOFs) as platforms for controlling thermal expansion devices that can operate in the negative, zero, and positive expansion regimes. A detailed computer simulation study, based on molecular dynamics, is presented to support the targeted application. MOF-5 has been selected as model material, along with three molecules of similar size and known differences in terms of the nature of host–guest interactions. It has been shown that adsorbate molecules can control, in a colligative way, the thermal expansion of the solid, so that changing the adsorbate molecules induces the solid to display positive, zero, or negative thermal expansion. We analyze in depth the distortion mechanisms, beyond the ligand metal junction, to cover the ligand distortions, and the energetic and entropic effect on the thermo-structural behavior. We provide an unprecedented atomistic insight on the effect of adsorbates on the thermal expansion of MOFs as a basic tool toward controlling the thermal expansion. PMID:28190918

  8. Controlling Thermal Expansion: A Metal-Organic Frameworks Route.

    Science.gov (United States)

    Balestra, Salvador R G; Bueno-Perez, Rocio; Hamad, Said; Dubbeldam, David; Ruiz-Salvador, A Rabdel; Calero, Sofia

    2016-11-22

    Controlling thermal expansion is an important, not yet resolved, and challenging problem in materials research. A conceptual design is introduced here, for the first time, for the use of metal-organic frameworks (MOFs) as platforms for controlling thermal expansion devices that can operate in the negative, zero, and positive expansion regimes. A detailed computer simulation study, based on molecular dynamics, is presented to support the targeted application. MOF-5 has been selected as model material, along with three molecules of similar size and known differences in terms of the nature of host-guest interactions. It has been shown that adsorbate molecules can control, in a colligative way, the thermal expansion of the solid, so that changing the adsorbate molecules induces the solid to display positive, zero, or negative thermal expansion. We analyze in depth the distortion mechanisms, beyond the ligand metal junction, to cover the ligand distortions, and the energetic and entropic effect on the thermo-structural behavior. We provide an unprecedented atomistic insight on the effect of adsorbates on the thermal expansion of MOFs as a basic tool toward controlling the thermal expansion.

  9. The [epsilon] expansion and the electroweak phase transition

    Energy Technology Data Exchange (ETDEWEB)

    Arnold, P.; Yaffe, L.G. (Department of Physics, University of Washington, Seattle, Washington 98195 (United States))

    1994-03-15

    Standard perturbative (or mean field theory) techniques are not adequate for studying the finite-temperature electroweak phase transition in some cases of interest to scenarios for electroweak baryogenesis. We instead study the properties of this transition using the renormalization group and the [epsilon] expansion. This expansion, based on dimensional continuation from 3 to 4--[epsilon] spatial dimensions, provides a systematic approximation for computing the effects of (near-)critical fluctuations. The [epsilon] expansion is known to predict a first-order transition in Higgs theories, even for heavy Higgs boson masses. The validity of this conclusion in the standard model is examined in detail. A variety of physical quantities are computed at leading and next-to-leading order in [epsilon]. For moderately light Higgs boson masses (below 100 GeV), the [epsilon] expansion suggests that the transition is more strongly first order than is predicted by the conventional analysis based on the one-loop (ring-improved) effective potential. Nevertheless, the rate of baryon nonconservation after the transition is found to be [ital larger] than that given by the one-loop effective potential calculation. Detailed next-to-leading order calculations of some sample quantities suggests that the [epsilon] expansion is reasonably well behaved for Higgs boson masses below 100--200 GeV. We also compare the [epsilon] expansion with large-[ital N] results (where [ital N] is the number of scalar fields) and find that the [epsilon] expansion is less well behaved in this limit.

  10. Asymptotic expansions for high-contrast elliptic equations

    KAUST Repository

    Calo, Victor M.

    2014-03-01

    In this paper, we present a high-order expansion for elliptic equations in high-contrast media. The background conductivity is taken to be one and we assume the medium contains high (or low) conductivity inclusions. We derive an asymptotic expansion with respect to the contrast and provide a procedure to compute the terms in the expansion. The computation of the expansion does not depend on the contrast which is important for simulations. The latter allows avoiding increased mesh resolution around high conductivity features. This work is partly motivated by our earlier work in [Domain decomposition preconditioners for multiscale flows in high-contrast media, Multiscale Model Simul. 8 (2010) 1461-1483] where we design efficient numerical procedures for solving high-contrast problems. These multiscale approaches require local solutions and our proposed high-order expansion can be used to approximate these local solutions inexpensively. In the case of a large-number of inclusions, the proposed analysis can help to design localization techniques for computing the terms in the expansion. In the paper, we present a rigorous analysis of the proposed high-order expansion and estimate the remainder of it. We consider both high-and low-conductivity inclusions. © 2014 World Scientific Publishing Company.

  11. Spatial and Temporal Dimensions of Urban Expansion in China.

    Science.gov (United States)

    Zhao, Shuqing; Zhou, Decheng; Zhu, Chao; Sun, Yan; Wu, Wenjia; Liu, Shuguang

    2015-08-18

    The scale of urbanization in China during the past three decades is unprecedented in human history, and the processes are poorly understood. Here we present an effort to map the urban land expansion processes of 32 major cities in China from 1978 to 2010 using Landsat satellite data to understand the temporal and spatial characteristics. Results showed that the urban extent of the 32 cities expanded exponentially with very high annual rates varying from 3.2% to 12.8%. Temporal fluctuation in urban expansion rates in these 32 cities was obvious, with unexpected and alarming expansion rates from 2005 to 2010 that drastically exceeded their expectation, which was calculated from the long-term trend between 1978 and 2005, by 45%. Overall, we found that the growth rates of cities during the entire study period were inversely related to city size, contradicting the theory or Gibrat's law, which states that the growth rate is independent of city size. More detailed analysis indicated that city growth in China has transitioned from contradicting to conforming to Gibrat's law since 1995. Our study suggests that the urban expansion theory (i.e., Gibrat's law) does not fit Chinese expansion consistently over time, and the exact causes are unknown. Exploring the causes in future research will improve our understanding of the theory and, more importantly, understand the feasibility of the theoretical relationship between city size and expansion rate in guiding contemporary urban expansion planning.

  12. Evolution of density-dependent movement during experimental range expansions.

    Science.gov (United States)

    Fronhofer, E A; Gut, S; Altermatt, F

    2017-12-01

    Range expansions and biological invasions are prime examples of transient processes that are likely impacted by rapid evolutionary changes. As a spatial process, range expansions are driven by dispersal and movement behaviour. Although it is widely accepted that dispersal and movement may be context-dependent, for instance density-dependent, and best represented by reaction norms, the evolution of density-dependent movement during range expansions has received little experimental attention. We therefore tested current theory predicting the evolution of increased movement at low densities at range margins using highly replicated and controlled range expansion experiments across multiple genotypes of the protist model system Tetrahymena thermophila. Although rare, we found evolutionary changes during range expansions even in the absence of initial standing genetic variation. Range expansions led to the evolution of negatively density-dependent movement at range margins. In addition, we report the evolution of increased intrastrain competitive ability and concurrently decreased population growth rates in range cores. Our findings highlight the importance of understanding movement and dispersal as evolving reaction norms and plastic life-history traits of central relevance for range expansions, biological invasions and the dynamics of spatially structured systems in general. © 2017 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2017 European Society For Evolutionary Biology.

  13. Evaluation on expansive performance of the expansive soil using electrical responses

    Science.gov (United States)

    Chu, Ya; Liu, Songyu; Bate, Bate; Xu, Lei

    2018-01-01

    Light structures, such as highways and railroads, built on expansive soils are prone to damages from the swelling of their underlain soil layers. Considerable amount of research has been conducted to characterize the swelling properties of expansive soils. Current swell characterization models, however, are limited by lack of standardized tests. Electrical methods are non-destructive, and are faster and less expensive than the traditional geotechnical methods. Therefore, geo-electrical methods are attractive for defining soil characteristics, including the swelling behavior. In this study, comprehensive laboratory experiments were undertaken to measure the free swelling and electrical resistivity of the mixtures of commercial kaolinite and bentonite. The electrical conductivity of kaolinite-bentonite mixtures was measured by a self-developed four-electrode soil resistivity box. Increasing the free swelling rate of the kaolinite-bentonite mixtures (0.72 to 1 of porosity of soils samples) led to a reduction in the electrical resistivity and an increase in conductivity. A unique relationship between free swelling rate and normalized surface conductivity was constructed for expensive soils by eliminating influences of porosity and m exponent. Therefore, electrical response measurement can be used to characterize the free swelling rate of expensive soils.

  14. Expansion plan of the electrical sector; Plan de expansion del sector electrico

    Energy Technology Data Exchange (ETDEWEB)

    Cristerna Ocampo, Rafael [Comision Federal de Electricidad (Mexico)

    1996-07-01

    An analysis of the Mexican electrical market in the year 1994 as far as sales of electrical energy and types of users who utilized that energy, is presented. In addition, an analysis is made of the options for the future supply, where the installed electrical capacity in Mexico in 1994 is described. Also the requirements of additional capacity of power generation, from year 1995 to year 2004 are analyzed. In the internal supply of primary energy in Mexico, the hydrocarbons represent 83%, the diversified sources (nuclear, geothermal, hydro and coal) represent 7% and the biomass as well as complementary coal, the 10% balance of the primary energy. Finally an expansion plan of the transmission network of the Mexican electrical system is described. [Spanish] Se presenta un analisis del mercado electrico mexicano en el ano de 1994 en cuanto a ventas de energia electrica y los tipos de usuarios que utilizaron esa energia. Se hace un analisis ademas, de las opciones para la oferta futura, donde se describe la capacidad electrica instalada de Mexico en 1994. Tambien se analizan los requerimientos de capacidad adicional de generacion de 1995 al 2004. En la oferta interna de energia primaria en Mexico, los hidrocarburos representan el 83%, las fuentes diversificadas (nuclear, geotermia, hidro y carboelectrica) representan el 7% y la biomasa asi como el carbon complementario, el 10% restante de la energia primaria. Finalmente se describe un plan de expansion de la red de transmision del sistema electrico mexicano.

  15. Evaluating expansion strategies for startup European Union dairy farm businesses.

    Science.gov (United States)

    McDonald, R; Shalloo, L; Pierce, K M; Horan, B

    2013-06-01

    A stochastic whole-farm simulation model was used to examine alternative strategies for new entrant dairy farmers to grow and develop dairy farm businesses in the context of European Union (EU) milk quota abolition in 2015. Six alternative strategies were compared: remain static, natural growth expansion, waiting until after EU milk quota abolition to expand, a full-scale expansion strategy without milk quotas and not incurring super levy penalties, a full-scale expansion strategy with milk quotas and incurring super levy penalties, and once-a-day milking until EU milk quota abolition, followed by full-scale expansion. Each discrete whole farm investment strategy was evaluated over a 15-yr period (2013-2027) using multiple financial stability and risk indicators, including overall discounted farm business profitability, net worth change, return on investment, and financial risk. The results of this study indicate that, although associated with increased risk, dairy farm expansion will ensure the future profitability of the farm business. Within the context of EU milk quotas until 2015, the most attractive expansion strategy is to increase cow numbers while avoiding super levy fines using once-a-day milking techniques, increasing to the full capacity of the dairy farm once milk quotas are removed. In contrast, the results also indicate that dairy farms that remain static will experience a significant reduction in farm profitability in the coming year due to production cost inflation. Cash flow deficits were observed during the initial year of expansion and, therefore, rapidly expanding dairy farm businesses require a significant cash reserve to alleviate business risk during the initial year of expansion. The results of this analysis also indicate that dairy farm businesses that expand using lower cost capital investments and avoid milk quota super levy fines significantly reduce the financial risks associated with expansion. Copyright © 2013 American Dairy Science

  16. Multiple pathways of commodity crop expansion in tropical forest landscapes

    Science.gov (United States)

    Meyfroidt, Patrick; Carlson, Kimberly M.; Fagan, Matthew E.; Gutiérrez-Vélez, Victor H.; Macedo, Marcia N.; Curran, Lisa M.; DeFries, Ruth S.; Dyer, George A.; Gibbs, Holly K.; Lambin, Eric F.; Morton, Douglas C.; Robiglio, Valentina

    2014-07-01

    Commodity crop expansion, for both global and domestic urban markets, follows multiple land change pathways entailing direct and indirect deforestation, and results in various social and environmental impacts. Here we compare six published case studies of rapid commodity crop expansion within forested tropical regions. Across cases, between 1.7% and 89.5% of new commodity cropland was sourced from forestlands. Four main factors controlled pathways of commodity crop expansion: (i) the availability of suitable forestland, which is determined by forest area, agroecological or accessibility constraints, and land use policies, (ii) economic and technical characteristics of agricultural systems, (iii) differences in constraints and strategies between small-scale and large-scale actors, and (iv) variable costs and benefits of forest clearing. When remaining forests were unsuitable for agriculture and/or policies restricted forest encroachment, a larger share of commodity crop expansion occurred by conversion of existing agricultural lands, and land use displacement was smaller. Expansion strategies of large-scale actors emerge from context-specific balances between the search for suitable lands; transaction costs or conflicts associated with expanding into forests or other state-owned lands versus smallholder lands; net benefits of forest clearing; and greater access to infrastructure in already-cleared lands. We propose five hypotheses to be tested in further studies: (i) land availability mediates expansion pathways and the likelihood that land use is displaced to distant, rather than to local places; (ii) use of already-cleared lands is favored when commodity crops require access to infrastructure; (iii) in proportion to total agricultural expansion, large-scale actors generate more clearing of mature forests than smallholders; (iv) property rights and land tenure security influence the actors participating in commodity crop expansion, the form of land use displacement

  17. The Lost Foam method – pre-expansion process

    Directory of Open Access Journals (Sweden)

    T. Pacyniak

    2010-04-01

    Full Text Available In the study, a pre-expansion station, designed by authors, was presented. It consists of a batch pre-expander with a 90 liters capacity foaming chamber, equipped with fluidized-solid dryer of pre-expanded beads and a pneumatic transport system of granules to the silo. Steam is delivered to the pre-expander from the electric vapor generator type LW 40.1. In the study, work principle of the pre-expansion station and pre-expansion tests carried out on this position were presented.

  18. DYN3D thermal expansion models for SFR applications

    Energy Technology Data Exchange (ETDEWEB)

    Nikitin, Evgeny; Fridman, Emil [Helmholtz-Zentrum Dresden-Rossendorf e.V., Dresden (Germany). Div. Reactor Safety

    2016-07-01

    The nodal diffusion code DYN3D is under extension for SFR applications. As a part of the extension a new model for axial thermal expansion of fuel rods was developed. The new model provides a flexible way of handling the axial fuel rod expansion, because each sub-assembly and node can be treated independently. The performance of the model was tested on a large oxide SFR core, and the results were compared to the reference full core Serpent solution. The test results indicated that the proposed model can accurately account for the axial expansion effects on full core level.

  19. Small dead-time expansion in counting distributions and moments

    Science.gov (United States)

    Ackermann, J.; Hogreve, H.

    2010-03-01

    Considering type I counters affected by a dead-time τ, we study the τ expansion of the probabilities and moments of the underlying stochastic renewal process. For the counting distributions and probabilities we extend results from the literature and analyse their approximation properties. Our results show, in particular, that for increasing counting numbers ever larger orders of the τ expansion are required for accurate approximations. Furthermore, the τ expansion for the first and second moments are obtained; their series is proved to coincide with the respective long time asymptotics. This asymptotics is demonstrated to converge exponentially fast to the exact quantities for growing time.

  20. Expansive Learning in Construction Projects - a Contradiction in terms?

    DEFF Research Database (Denmark)

    Klitgaard, Anne; Nissen, Søren Bülow; Beck, Frederikke

    2016-01-01

    This research is a preliminary study performed as part of a primary research into expansive learning in interorganizational network set up to solve a construction project. The construction industry has long had issues about productivity, which can be an indication of lack of learning. A case study...... acquisition and participation but not by expansive learning. The construction industry needs to accept that the learning generated from projects will be limited to learning by acquisition and participation. The interorganizational network cannot facilitate expansive learning while working on object......-fixed projects. Research in construction management fails to generate and document knowledge because of the limitations of case studies....

  1. Edgeworth expansion for the pre-averaging estimator

    DEFF Research Database (Denmark)

    Podolskij, Mark; Veliyev, Bezirgen; Yoshida, Nakahiro

    asymptotic variance. Our approach is based on martingale embedding, Malliavin calculus and stable central limit theorems for continuous diffusions. Moreover, we derive the density expansion for the studentized statistic, which might be applied to construct asymptotic confidence regions.......In this paper, we study the Edgeworth expansion for a pre-averaging estimator of quadratic variation in the framework of continuous diffusion models observed with noise. More specifically, we obtain a second order expansion for the joint density of the estimators of quadratic variation and its...

  2. Chemical Expansion: Implications for Electrochemical Energy Storage and Conversion Devices

    DEFF Research Database (Denmark)

    Bishop, S.R.; Marrocchelli, D.; Chatzichristodoulou, Christodoulos

    2014-01-01

    Many energy-related materials rely on the uptake and release of large quantities of ions, for example, Li+ in batteries, H+ in hydrogen storage materials, and O2− in solid-oxide fuel cell and related materials. These compositional changes often result in large volumetric dilation of the material...... modeling and an overview of factors impacting chemical expansion. We discuss the implications of chemical expansion for mechanical stability and functionality in the energy applications above, as well as in other oxide-based systems. The use of chemical expansion as a new means to probe other materials...

  3. Mechanism of actuation in conducting polymers: Osmotic expansion

    DEFF Research Database (Denmark)

    Bay, Lasse; Jacobsen, Torben; West, Keld

    2001-01-01

    Conducting polymers expand or contract when their redox state is changed. This expansion/contraction effect can be separated in an intrinsic part because of changes of the polymer backbone on reduction/oxidation and a part depending on the surrounding electrolyte phase, because of osmotic expansion...... of the polymer phase. The osmotic effect causes solvent molecules to move into the polymer in a number far in excess of those bound strongly in the solvation shell of the mobile ion, resulting in large volume changes. In this paper, a thermodynamic description of the osmotic expansion is worked out. The model...

  4. Global Grid of Probabilities of Urban Expansion to 2030

    Data.gov (United States)

    National Aeronautics and Space Administration — The Global Grid of Probabilities of Urban Expansion to 2030 presents spatially explicit probabilistic forecasts of global urban land cover change from 2000 to 2030...

  5. Observed poleward expansion of the Hadley circulation since 1979

    Directory of Open Access Journals (Sweden)

    Y. Hu

    2007-10-01

    Full Text Available Using three meteorological reanalyses and three outgoing long-wave radiation (OLR datasets, we show that the Hadley circulation has a significant expansion of about 2 to 4.5 degrees of latitude since 1979. The three reanalyses all indicate that the poleward expansion of the Hadley circulation in each hemisphere occurs during its summer and fall seasons. Results from the OLR datasets do not have such seasonality. The expansion of the Hadley circulation implies a poleward expansion of the band of subtropical subsidence, leading to enhanced mid-latitude tropospheric warming and poleward shifts of the subtropical dry zone. This would contribute to an increased frequency of midlatitude droughts in both hemispheres.

  6. Yes and no to grid expansion.; Jein zum Netzausbau.

    Energy Technology Data Exchange (ETDEWEB)

    Huebner, Gundula; Pohl, Johannes [Halle-Wittenberg Univ. (Germany). Inst. fuer Psychologie

    2011-09-15

    The construction of new power plants using renewable energy sources necessitates expansion of power transmission grids. Everyone is in agreement about that, but there is disagreement about the details.

  7. Effect of rapid maxillary expansion on sleep characteristics in children

    National Research Council Canada - National Science Library

    Ashok, Navya; Varma, N K Sapna; Ajith, V V; Gopinath, Siby

    2014-01-01

    Rapid maxillary expansion (RME) is an orthopedic treatment procedure routinely used to treat constricted maxillary arches and also a potential additional treatment in children presenting with sleep-disordered breathing (SDB...

  8. Effect of rapid maxillary expansion on sleep characteristics in children

    National Research Council Canada - National Science Library

    Navya Ashok; N. K. Sapna Varma; V V Ajith; Siby Gopinath

    2014-01-01

    Introduction: Rapid maxillary expansion (RME) is an orthopedic treatment procedure routinely used to treat constricted maxillary arches and also a potential additional treatment in children presenting with sleep-disordered breathing (SDB...

  9. Seal assembly for materials with different coefficients of thermal expansion

    Science.gov (United States)

    Minford, Eric [Laurys Station, PA

    2009-09-01

    Seal assembly comprising (a) two or more seal elements, each element having having a coefficient of thermal expansion; and (b) a clamping element having a first segment, a second segment, and a connecting segment between and attached to the first and second segments, wherein the two or more seal elements are disposed between the first and second segments of the clamping element. The connecting segment has a central portion extending between the first segment of the clamping element and the second segment of the clamping element, and the connecting segment is made of a material having a coefficient of thermal expansion. The coefficient of thermal expansion of the material of the connecting segment is intermediate the largest and smallest of the coefficients of thermal expansion of the materials of the two or more seal elements.

  10. Geographic Expansion Strategic Model in Iran: A Qualitative Study

    Directory of Open Access Journals (Sweden)

    Shahram Yazdani

    2016-12-01

    Conclusion: For promotion of community health and improvement of the national and international position of Iran’s medical universities and HE centers, policymakers should consider the diverse factors that influence HE expansion in our developed model.

  11. The Electroweak Phase Transition, Part 2: $\\epsilon$-Expansion Results

    OpenAIRE

    Yaffe, Laurence

    1994-01-01

    Talk presented at the conference Quarks `94: Vladimir, Russia. I summarize the application of $\\epsilon$-expansion methods to the electroweak phase transition. Results from both leading and next-to-leading order calculations are discussed.

  12. Generation and transmission expansion planning for renewable energy integration

    Energy Technology Data Exchange (ETDEWEB)

    Bent, Russell W [Los Alamos National Laboratory; Berscheid, Alan [Los Alamos National Laboratory; Toole, G. Loren [Los Alamos National Laboratory

    2010-11-30

    In recent years the expansion planning problem has become increasingly complex. As expansion planning (sometimes called composite or integrated resource planning) is a non-linear and non-convex optimization problem, researchers have traditionally focused on approximate models of power flows to solve the problem. The problem has also been split into generation expansion planning (GEP) and transmission network expansion planning (TNEP) to improve computational tractability. Until recently these approximations have produced results that are straight-forward to combine and adapt to the more complex and complete problem. However, the power grid is evolving towards a state where the adaptations are no longer easy (e.g. large amounts of limited control, renewable generation, comparable generation and transmission construction costs) and necessitates new approaches. Recent work on deterministic Discrepancy Bounded Local Search (DBLS) has shown it to be quite effective in addressing the TNEP. In this paper, we propose a generalization of DBLS to handle simultaneous generation and transmission planning.

  13. Linear delta expansion technique for the solution of anharmonic ...

    Indian Academy of Sciences (India)

    The linear delta expansion technique has been developed for solving the differential equation of motion for symmetric and asymmetric anharmonic oscillators. We have also demonstrated the sophistication and simplicity of this new perturbation technique.

  14. Soil Organic Carbon Responses to Forest Expansion on Mountain Grasslands

    DEFF Research Database (Denmark)

    Guidi, Claudia

    Grassland abandonment followed by progressive forest expansion is the dominant land-use change in the European Alps. Contrasting trends in soil organic carbon (SOC) stocks have been reported for mountainous regions following forest expansion on grasslands. Moreover, its effects on SOC properties....... Changes in labile soil C were assessed by carbohydrate and thermal analyses of soil samples and fractions. Forest expansion on mountain grasslands caused a decrease in SOC stocks within the mineral soil. The SOC accumulation within the organic layers following forest establishment could not fully...... involved into long-term stability are largely unknown. The aim of this PhD thesis was to explore changes in: (i) SOC stocks; (ii) physical SOC fractions; and (iii) labile soil carbon components following forest expansion on mountain grasslands. A land-use gradient located in the Southern Alps (Italy...

  15. QUANTUM SPACE AND THE EXPANSION OF THE UNIVERSE

    OpenAIRE

    CARLOS A. MELENDRES

    2017-01-01

    A new quantum model of space  and the evolution of the universe is presented. They provide a a mechanism to explain the accelerated expansion of the universe, dark energy,  and the nature of dark matter.

  16. Negative thermal expansion near two structural quantum phase transitions

    Energy Technology Data Exchange (ETDEWEB)

    Occhialini, Connor A.; Handunkanda, Sahan U.; Said, Ayman; Trivedi, Sudhir; Guzmán-Verri, G. G.; Hancock, Jason N.

    2017-12-01

    Recent experimental work has revealed that the unusually strong, isotropic structural negative thermal expansion in cubic perovskite ionic insulator ScF3 occurs in excited states above a ground state tuned very near a structural quantum phase transition, posing a question of fundamental interest as to whether this special circumstance is related to the anomalous behavior. To test this hypothesis, we report an elastic and inelastic x-ray scattering study of a second system Hg2I2 also tuned near a structural quantum phase transition while retaining stoichiometric composition and high crystallinity. We find similar behavior and significant negative thermal expansion below 100 K for dimensions along the body-centered-tetragonal c axis, bolstering the connection between negative thermal expansion and zero-temperature structural transitions.We identify the common traits between these systems and propose a set of materials design principles that can guide discovery of newmaterials exhibiting negative thermal expansion

  17. Fixed Points of Expansive Type Mappings in 2-Banach Spaces

    Directory of Open Access Journals (Sweden)

    Prabha Chouhan

    2013-08-01

    Full Text Available In present paper, we define expansive mappings in 2-Banach space and prove some common unique fixed point theorems which are the extension of results of Wang et al. [12] and Rhoades [9] in 2-Banach space.

  18. Short interval expansion of Rényi entropy on torus

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Bin [Department of Physics and State Key Laboratory of Nuclear Physics and Technology,Peking University,5 Yiheyuan Rd, Beijing 100871 (China); Collaborative Innovation Center of Quantum Matter,5 Yiheyuan Rd, Beijing 100871 (China); Center for High Energy Physics, Peking University,5 Yiheyuan Rd, Beijing 100871 (China); Wu, Jun-Bao [Theoretical Physics Division, Institute of High Energy Physics, Chinese Academy of Sciences,19B Yuquan Rd, Beijing 100049 (China); Theoretical Physics Center for Science Facilities, Chinese Academy of Sciences,19B Yuquan Rd, Beijing 100049 (China); Center for High Energy Physics, Peking University,5 Yiheyuan Rd, Beijing 100871 (China); Zhang, Jia-ju [Theoretical Physics Division, Institute of High Energy Physics, Chinese Academy of Sciences,19B Yuquan Rd, Beijing 100049 (China); Theoretical Physics Center for Science Facilities, Chinese Academy of Sciences,19B Yuquan Rd, Beijing 100049 (China)

    2016-08-23

    We investigate the short interval expansion of the Rényi entropy for two-dimensional conformal field theory (CFT) on a torus. We require the length of the interval ℓ to be small with respect to the spatial and temporal sizes of the torus. The operator product expansion of the twist operators allows us to compute the short interval expansion of the Rényi entropy at any temperature. In particular, we pay special attention to the large c CFTs dual to the AdS{sub 3} gravity and its cousins. At both low and high temperature limits, we read the Rényi entropies to order ℓ{sup 6}, and find good agreements with holographic results. Moreover, the expansion allows us to read 1/c contribution, which is hard to get by expanding the thermal density matrix. We generalize the study to the case with the chemical potential as well.

  19. Expansion coding: Achieving the capacity of an AEN channel

    CERN Document Server

    Koyluoglu, O Ozan; Si, Hongbo; Vishwanath, Sriram

    2012-01-01

    A general method of coding over expansions is proposed, which allows one to reduce the highly non-trivial problem of coding over continuous channels to a much simpler discrete ones. More specifically, the focus is on the additive exponential noise (AEN) channel, for which the (binary) expansion of the (exponential) noise random variable is considered. It is shown that each of the random variables in the expansion corresponds to independent Bernoulli random variables. Thus, each of the expansion levels (of the underlying channel) corresponds to a binary symmetric channel (BSC), and the coding problem is reduced to coding over these parallel channels while satisfying the channel input constraint. This optimization formulation is stated as the achievable rate result, for which a specific choice of input distribution is shown to achieve a rate which is arbitrarily close to the channel capacity in the high SNR regime. Remarkably, the scheme allows for low-complexity capacity-achieving codes for AEN channels, using...

  20. Medicaid Managed Care Penetration Rates and Expansion Enr...

    Data.gov (United States)

    U.S. Department of Health & Human Services — The Medicaid managed care penetration rates and expansion enrollment by state charts are composed annually by the Data and System Group (DSG) of the Centers for...

  1. Compact representation of radiation patterns using spherical mode expansions

    Energy Technology Data Exchange (ETDEWEB)

    Simpson, T.L.; Chen, Yinchao (South Carolina Univ., Columbia, SC (USA). Dept. of Electrical and Computer Engineering)

    1990-07-15

    This report presents the results of an investigation of SM (Spherical Mode) expansions as a compact and efficient alternative to the use of current distributions for generating radiation patterns. The study included three areas: (1) SM expansion from the radiation pattern; (2) SM expansion from the antenna current; and (3) Literature search. SM expansions were obtained from radiation patterns during the initial phase of this study. Although straightforward in principal, however, this technique was found to be awkward for the treatment on theoretical radiation patterns. It is included here for completeness and for possible use to summarize experimental results in a more meaningful way than with an exhaustive display of amplitude with azimuth and elevation angles. In essence, the work in this area served as as warm-up problem to develop our skills in computing and manipulating spherical modes as mathematical entities. 6 refs., 21 figs., 6 tabs.

  2. INVESTIGATION OF HOLOCENE FAULTING PROPOSED C-746-U LANDFILL EXPANSION

    Energy Technology Data Exchange (ETDEWEB)

    Lettis, William [William Lettis & Associates, Inc.

    2006-07-01

    This report presents the findings of a fault hazard investigation for the C-746-U landfill's proposed expansion located at the Department of Energy's (DOE) Paducah Gaseous Diffusion Plant (PGDP), in Paducah, Kentucky. The planned expansion is located directly north of the present-day C-746-U landfill. Previous geophysical studies within the PGDP site vicinity interpret possible northeast-striking faults beneath the proposed landfill expansion, although prior to this investigation the existence, locations, and ages of these inferred faults have not been confirmed through independent subsurface exploration. The purpose of this investigation is to assess whether or not Holocene-active fault displacement is present beneath the footprint of the proposed landfill expansion.

  3. Integrating agricultural expansion into conservation biogeography: conflicts and priorities

    Directory of Open Access Journals (Sweden)

    Ricardo Dobrovolski

    2014-06-01

    Full Text Available Increasing food production without compromising biodiversity is one of the great challenges for humanity. The aims of my thesis were to define spatial priorities for biodiversity conservation and to evaluate conservation conflicts considering agricultural expansion in the 21st century. I also tested the effect of globalizing conservation efforts on both food production and biodiversity conservation. I found spatial conflicts between biodiversity conservation and agricultural expansion. However, incorporating agricultural expansion data into the spatial prioritization process can significantly alleviate conservation conflicts, by reducing spatial correlation between the areas under high impact of agriculture and the priority areas for conservation. Moreover, developing conservation blueprints at the global scale, instead of the usual approach based on national boundaries, can benefit both food production and biodiversity. Based on these findings I conclude that the incorporation of agricultural expansion as a key component for defining global conservation strategies should be added to the list of solutions for our cultivated planet.

  4. Can confidence indicators forecast the probability of expansion in Croatia?

    Directory of Open Access Journals (Sweden)

    Mirjana Čižmešija

    2016-04-01

    Full Text Available The aim of this paper is to investigate how reliable are confidence indicators in forecasting the probability of expansion. We consider three Croatian Business Survey indicators: the Industrial Confidence Indicator (ICI, the Construction Confidence Indicator (BCI and the Retail Trade Confidence Indicator (RTCI. The quarterly data, used in the research, covered the periods from 1999/Q1 to 2014/Q1. Empirical analysis consists of two parts. The non-parametric Bry-Boschan algorithm is used for distinguishing periods of expansion from the period of recession in the Croatian economy. Then, various nonlinear probit models were estimated. The models differ with respect to the regressors (confidence indicators and the time lags. The positive signs of estimated parameters suggest that the probability of expansion increases with an increase in Confidence Indicators. Based on the obtained results, the conclusion is that ICI is the most powerful predictor of the probability of expansion in Croatia.

  5. Rocky Mountain Arsenal Lower Derby Lake shoreline expansion project

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The purpose of this Project Completion Report is to document the completion of the Lower Derby Lake Shoreline Expansion Project and summarize project highlights....

  6. Gateway Arch Circulator Conceptual Feasibility Study : Jefferson National Expansion Memorial

    Science.gov (United States)

    2015-03-01

    The Jefferson National Expansion Memorial (JEFF) is undergoing major design changes as part of the City Arch River 2015 project (CAR) that will impact access for park visitors. The park and stakeholders are considering a circulator system to facilita...

  7. The expansion rate and size of the universe

    CERN Multimedia

    Freedman, Wendy L

    1998-01-01

    The age, evolution and fate of the universe depend on just how fast it is expanding. By measuring the size of the universe using a variety of new techniques, astronomers have recently improved estimates of the expansion rate

  8. Differential cosmic expansion and the Hubble flow anisotropy

    Science.gov (United States)

    Bolejko, Krzysztof; Nazer, M. Ahsan; Wiltshire, David L.

    2016-06-01

    The Universe on scales 01-100 h-1Mpc is dominated by a cosmic web of voids, filaments, sheets and knots of galaxy clusters. These structures participate differently in the global expansion of the Universe: from non-expanding clusters to the above average expansion rate of voids. In this paper we characterize Hubble expansion anisotropies in the COMPOSITE sample of 4534 galaxies and clusters. We concentrate on the dipole and quadrupole in the rest frame of the Local Group. These both have statistically significant amplitudes. These anisotropies, and their redshift dependence, cannot be explained solely by a boost of the Local Group in the Friedmann-Lemaitre-Robertson-Walker (FLRW) model which expands isotropically in the rest frame of the cosmic microwave background (CMB) radiation. We simulate the local expansion of the Universe with inhomogeneous Szekeres solutions, which match the standard FLRW model on gtrsim 100 h-1Mpc scales but exhibit nonkinematic relativistic differential expansion on small scales. We restrict models to be consistent with observed CMB temperature anisotropies, while simultaneously fitting the redshift variation of the Hubble expansion dipole. We include features to account for both the Local Void and the "Great Attractor". While this naturally accounts for the Hubble expansion and CMB dipoles, the simulated quadrupoles are smaller than observed. Further refinement to incorporate additional structures may improve this. This would enable a test of the hypothesis that some large angle CMB anomalies result from failing to treat the relativistic differential expansion of the background geometry; a natural feature of solutions to Einstein's equations not included in the current standard model of cosmology.

  9. Separable Ernst-Shakin-Thaler expansions of local potentials

    Science.gov (United States)

    Bund, Gerhard Wilhelm

    1985-06-01

    The boundary condition Ernst-Shakin-Thaler method, introduced previously to generate separable expansions of local potentials of finite range, is applied to the study of the triplet s-wave Malfliet-Tjon potential. The effect of varying the radius where the boundary condition is applied on the T matrix is analyzed. Further, we compare the convergence of the n-d scattering cross sections in the quartet state below the breakup threshold for expansions corresponding to two different boundaries.

  10. UTD at TREC 2014: Query Expansion for Clinical Decision Support

    Science.gov (United States)

    2014-11-01

    medical knowledge bases, such as the Unified Medical Language System ( UMLS ), the Systemized Nomenclature of Medicine – Clini- cal Terms (SNOMED-CT...System ( UMLS ), the Systemized Nomenclature of Medicine { Clini- cal Terms (SNOMED-CT), and Wikipedia as well as unsupervised distributional representa...following subsections describe the four methods of query expansion that we have considered. UMLS Expansions of fatigue) weariness lack of energy fatigue

  11. Thermal expansion of spinel-type Si3N4

    DEFF Research Database (Denmark)

    Paszkowics, W.; Minkikayev, R.; Piszora, P.

    2004-01-01

    The lattice parameter and thermal expansion coefficient (TEC) for the spinel-type Si3N4 phase prepared under high-pressure and high-temperature conditions are determined for 14 K......The lattice parameter and thermal expansion coefficient (TEC) for the spinel-type Si3N4 phase prepared under high-pressure and high-temperature conditions are determined for 14 K...

  12. Unduland universe: expansion with alternating eras of acceleration and deceleration

    OpenAIRE

    Barenboim Szuchman, Gabriela Alejandra; Mena Requejo, Olga; Quigg, Chris

    2005-01-01

    If the equation of state for "dark energy" varies periodically, the expansion of the Universe may have undergone alternating eras of acceleration and deceleration. We examine a specific form that survives existing observational tests, does not single out the present state of the Universe as exceptional, and suggests a future much like the matter-dominated past: a smooth expansion without a final inflationary epoch.

  13. Transmission Network Expansion Planning Considering Phase-Shifter Transformers

    OpenAIRE

    Miasaki, Celso T.; Franco, Edgar M. C.; Romero, Ruben A.

    2012-01-01

    This paper presents a novel mathematical model for the transmission network expansion planning problem. Main idea is to consider phase-shifter (PS) transformers as a new element of the transmission system expansion together with other traditional components such as transmission lines and conventional transformers. In this way, PS are added in order to redistribute active power flows in the system and, consequently, to diminish the total investment costs due to new transmission lines. Proposed...

  14. Use of Expansion Turbines in Natural Gas Pressure Reduction Stations

    Directory of Open Access Journals (Sweden)

    Poživil Jaroslav

    2004-09-01

    Full Text Available Through the use of expansion turbines in natural gas pressure reduction stations it is possible to produce clean, “green” electricity.Such energy recovery unit utilize the potential energy of natural gas being delivered under high pressure. Expansion turbines are not onlyefficient and profitable but meet the environmental criteria – no emissions of sulfur dioxide, nitrogen oxides or carbon dioxide.

  15. Cylinder expansion test and gas gun experiment comparison

    Energy Technology Data Exchange (ETDEWEB)

    Harrier, Danielle [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-06-30

    This is a summer internship presentation by the Hydro Working Group at Los Alamos National Laboratory (LANL) and goes into detail about their cylinder expansion test and gas gun experiment comparison. Specifically, the gas gun experiment is detailed along with applications, the cylinder expansion test is detailed along with applications, there is a comparison of the methods with pros and cons and limitations listed, the summer project is detailed, and future work is talked about.

  16. AL-HARM EXPANSION MOVIE BASED ON VIRTUAL REALITY

    OpenAIRE

    Alanoud Salem; Sara Musallam; El-Shaimaa Nada; Ahmed Ahmed

    2015-01-01

    Animated movies are excellent virtual environments for creating models in high quality. Animated movies can include 3D models, sounds and lights effects, and detailed maps. In this paper, a virtual reality movie is applied to Al-Haram Expansion stages including the future stage of expansion. 3DMAX program is used to rich the maximum benefits of using 3D modeling. Maps with details are built by using ARCGIS program in order to understand the real difference between the three dif...

  17. Experimental Test for epsilon-Expansions with n=4

    DEFF Research Database (Denmark)

    Ott, H. R.; Kjems, Jørgen

    1980-01-01

    epsilon (Porson)-expansion calculations predict the magnetic phase transitions of the Ce monochalcogenides to be first order. We present experimental evidence that the transitions in CeSe and CeTe are continuous.......epsilon (Porson)-expansion calculations predict the magnetic phase transitions of the Ce monochalcogenides to be first order. We present experimental evidence that the transitions in CeSe and CeTe are continuous....

  18. Early Medicaid Expansion Associated With Reduced Payday Borrowing In California.

    Science.gov (United States)

    Allen, Heidi; Swanson, Ashley; Wang, Jialan; Gross, Tal

    2017-10-01

    We examined the impact of California's early Medicaid expansion under the Affordable Care Act on the use of payday loans, a form of high-interest borrowing used by low- and middle-income Americans. Using a data set for the period 2009-13 (roughly twenty-four months before and twenty-four months after the 2011-12 Medicaid expansion) that covered the universe of payday loans from five large payday lenders with locations around the United States, we used a difference-in-differences research design to assess the effect of the expansion on payday borrowing, comparing trends in early-expansion counties in California to those in counties nationwide that did not expand early. The early Medicaid expansion was associated with an 11 percent reduction in the number of loans taken out each month. It also reduced the number of unique borrowers each month and the amount of payday loan debt. We were unable to determine precisely how and for whom the expansion reduced payday borrowing, since to our knowledge, no data exist that directly link payday lending to insurance status. Nonetheless, our results suggest that Medicaid reduced the demand for high-interest loans and improved the financial health of American families. Project HOPE—The People-to-People Health Foundation, Inc.

  19. Volume of Plasma Expansion and Functional Outcomes in Stroke.

    Science.gov (United States)

    Miller, Joseph B; Lewandowski, Christopher; Wira, Charles R; Taylor, Andrew; Burmeister, Charlotte; Welch, Robert

    2017-04-01

    Plasma expansion in acute ischemic stroke has potential to improve cerebral perfusion, but the long-term effects on functional outcome are mixed in prior trials. The goal of this study was to evaluate how the magnitude of plasma expansion affects neurological recovery in acute stroke. This was a secondary analysis of data from the Albumin in Acute Stroke Part 2 trial investigating the relationship between the magnitude of overall intravenous volume infusion (crystalloid and colloid) to clinical outcome. The data were inclusive of 841 patients with a mean age of 64 years and a median National Institutes of Health Stroke Scale (NIHSS) of 11. In a multivariable-adjusted logistic regression model, this analysis tested the volume of plasma expansion over the first 48 h of hospitalization as a predictor of favorable outcome, defined as either a modified Rankin Scale score of 0 or 1 or a NIHSS score of 0 or 1 at 90 days. This model included all study patients, irrespective of albumin or isotonic saline treatment. Patients that received higher volumes of plasma expansion more frequently had large vessel ischemic stroke and higher NIHSS scores. The multivariable-adjusted model revealed that there was decreased odds of a favorable outcome for every 250 ml additional volume plasma expansion over the first 48 h (OR 0.91, 95 % CI, 0.88-0.94). The present study demonstrates an association between greater volume of plasma expansion and worse neurological recovery.

  20. Strong anisotropic thermal expansion in cristobalite-type BPO 4

    Science.gov (United States)

    Achary, S. N.; Tyagi, A. K.

    2004-11-01

    In this communication, the thermal expansion behavior of cristobalite-type BPO 4, determined from high-temperature X-ray diffraction studies, is being reported. BPO 4 crystallizes in tetragonal lattice, with space group I-4 (No. 82) at room temperature, with unit cell parameters: a=4.3447(2), c=6.6415(5) Å and V=125.37(1) Å 3. The tetragonal unit cell parameters at 900 °C are: a=4.3939(2), c=6.6539(6) Å and V=128.46(1) Å 3. The results show a very strong anisotropic expansion in the lattice, with the typical thermal expansion coefficients along a- and c-axis 12.9×10 -6 and 2.1×10 -6/°C, respectively. The volume thermal expansion coefficient of the lattice is 28.2×10 -6/°C in the temperature range of 25-900 °C. The variation of the crystal structure with temperature and the thermal expansion behavior are explained in this manuscript. The role of inter-polyhedral angle on the thermal expansion behavior has also been established.

  1. Transverse Expansion and Stability after Segmental Le Fort I Osteotomy versus Surgically Assisted Rapid Maxillary Expansion: a Systematic Review

    Directory of Open Access Journals (Sweden)

    Thomas Starch-Jensen

    2017-01-01

    Full Text Available Objectives: The objective of the present systematic review was to test the hypothesis of no difference in transverse skeletal and dental arch expansion and relapse after segmental Le Fort I osteotomy versus surgically assisted rapid maxillary expansion. Material and Methods: A MEDLINE (PubMed, Embase and Cochrane library search in combination with a hand-search of relevant journals was conducted by including human studies published in English from January 1, 2000 to June 1, 2016. Results: The search provided 130 titles and four studies fulfilled the inclusion criteria. All the included studies were characterized by high risk of bias and meta-analysis was not possible due to considerable variation. Both treatment modalities significantly increase the transverse maxillary skeletal and dental arch width. The transverse dental arch expansion and relapse seems to be substantial higher with tooth-borne surgically assisted rapid maxillary expansion compared to segmental Le Fort I osteotomy. The ratio of dental to skeletal relapse was significantly higher in the posterior maxilla with tooth-borne surgically assisted rapid maxillary expansion. Moreover, a parallel opening without segment tilting was observed after segmental Le Fort I osteotomy. Conclusions: Maxillary transverse deficiency in adults can be treated successfully with both treatment modalities, although surgically assisted rapid maxillary expansion seems more effective when large transverse maxillary skeletal and dental arch expansion is required. However, considering the methodological limitations of the included studies, long-term randomized studies assessing transverse skeletal and dental expansion and relapse with the two treatment modalities are needed before definite conclusions can be provided.

  2. Early Impacts of the Affordable Care Act on Health Insurance Coverage in Medicaid Expansion and Non-Expansion States.

    Science.gov (United States)

    Courtemanche, Charles; Marton, James; Ukert, Benjamin; Yelowitz, Aaron; Zapata, Daniela

    2017-01-01

    The Affordable Care Act (ACA) aimed to achieve nearly universal health insurance coverage in the United States through a combination of insurance market reforms, mandates, subsidies, health insurance exchanges, and Medicaid expansions, most of which took effect in 2014. This paper estimates the causal effects of the ACA on health insurance coverage in 2014 using data from the American Community Survey. We utilize difference-in-difference-in-differences models that exploit cross-sectional variation in the intensity of treatment arising from state participation in the Medicaid expansion and local area pre-ACA uninsured rates. This strategy allows us to identify the effects of the ACA in both Medicaid expansion and non-expansion states. Our preferred specification suggests that, at the average pre-treatment uninsured rate, the full ACA increased the proportion of residents with insurance by 5.9 percentage points compared to 2.8 percentage points in states that did not expand Medicaid. Private insurance expansions from the ACA were due to increases in both employer-provided and non-group coverage. The coverage gains from the full ACA were largest for those without a college degree, non-whites, young adults, unmarried individuals, and those without children in the home. We find no evidence that the Medicaid expansion crowded out private coverage.

  3. Breaking the link between environmental degradation and oil palm expansion: a method for enabling sustainable oil palm expansion.

    Directory of Open Access Journals (Sweden)

    Hans Harmen Smit

    Full Text Available Land degradation is a global concern. In tropical areas it primarily concerns the conversion of forest into non-forest lands and the associated losses of environmental services. Defining such degradation is not straightforward hampering effective reduction in degradation and use of already degraded lands for more productive purposes. To facilitate the processes of avoided degradation and land rehabilitation, we have developed a methodology in which we have used international environmental and social sustainability standards to determine the suitability of lands for sustainable agricultural expansion. The method was developed and tested in one of the frontiers of agricultural expansion, West Kalimantan province in Indonesia. The focus was on oil palm expansion, which is considered as a major driver for deforestation in tropical regions globally. The results suggest that substantial changes in current land-use planning are necessary for most new plantations to comply with international sustainability standards. Through visualizing options for sustainable expansion with our methodology, we demonstrate that the link between oil palm expansion and degradation can be broken. Application of the methodology with criteria and thresholds similar to ours could help the Indonesian government and the industry to achieve its pro-growth, pro-job, pro-poor and pro-environment development goals. For sustainable agricultural production, context specific guidance has to be developed in areas suitable for expansion. Our methodology can serve as a template for designing such commodity and country specific tools and deliver such guidance.

  4. Breaking the link between environmental degradation and oil palm expansion: a method for enabling sustainable oil palm expansion.

    Science.gov (United States)

    Harmen Smit, Hans; Meijaard, Erik; van der Laan, Carina; Mantel, Stephan; Budiman, Arif; Verweij, Pita

    2013-01-01

    Land degradation is a global concern. In tropical areas it primarily concerns the conversion of forest into non-forest lands and the associated losses of environmental services. Defining such degradation is not straightforward hampering effective reduction in degradation and use of already degraded lands for more productive purposes. To facilitate the processes of avoided degradation and land rehabilitation, we have developed a methodology in which we have used international environmental and social sustainability standards to determine the suitability of lands for sustainable agricultural expansion. The method was developed and tested in one of the frontiers of agricultural expansion, West Kalimantan province in Indonesia. The focus was on oil palm expansion, which is considered as a major driver for deforestation in tropical regions globally. The results suggest that substantial changes in current land-use planning are necessary for most new plantations to comply with international sustainability standards. Through visualizing options for sustainable expansion with our methodology, we demonstrate that the link between oil palm expansion and degradation can be broken. Application of the methodology with criteria and thresholds similar to ours could help the Indonesian government and the industry to achieve its pro-growth, pro-job, pro-poor and pro-environment development goals. For sustainable agricultural production, context specific guidance has to be developed in areas suitable for expansion. Our methodology can serve as a template for designing such commodity and country specific tools and deliver such guidance.

  5. In vitro evaluation of force-expansion characteristics in a newly designed orthodontic expansion screw compared to conventional screws

    Directory of Open Access Journals (Sweden)

    Oshagh Morteza

    2009-01-01

    Full Text Available Objective : Expansion screws like Hyrax, Haas and other types, produce heavy interrupted forces which are unfavorable for dental movement and could be harmful to the tooth and periodontium. The other disadvantage of these screws is the need for patient cooperation for their regular activation. The purpose of this study was to design a screw and compare its force- expansion curve with other types. Materials and Methods : A new screw was designed and fabricated in the same dimension, with conventional types, with the ability of 8 mm expansion (Free wire length: 12 mm, initial compression: 4.5 mm, spring wire diameter: 0.4 mm, spring diameter: 3 mm, number of the coils: n0 ine, material: s0 tainless steel. In this in vitro study, the new screw was placed in an acrylic orthodontic appliance, and after mounting on a stone cast, the force-expansion curve was evaluated by a compression test machine and compared to other screws. Results : Force-expansion curve of designed screw had a flatter inclination compared to other screws. Generally it produced a light continuous force (two to 3.5 pounds for every 4 mm of expansion. Conclusion : In comparison with heavy and interrupted forces of other screws, the newly designed screw created light and continuous forces.

  6. The acoustics of short circular holes with finite expansion ratio

    Science.gov (United States)

    Yang, Dong; Morgans, Aimee

    2016-11-01

    The acoustic response of a circular hole with mean flow passing through it is highly relevant to Helmholtz resonators, fuel injectors, perforated liners, perforated plates and many other engineering applications. Analytical models for the acoustic response of these holes often ignore the impact of a finite expansion ratio either side, or account for it simply by adding an end mass inertial correction derived from the no mean flow assumption. The vortex-sound interaction within a short hole has been recently shown to strongly affect the acoustic response in the low frequency region. The present study uses an analytical model based on the Green's function method to investigate how the expansion ratios either side of a short hole affect the vortex-sound interaction within it - something neglected by previous models. This model is then incorporated into a Helmholtz resonator model, allowing us to consider the effect of a finite neck-to-cavity expansion ratio and the vortex-sound interaction within the finite length neck. Large resistance and acoustic energy absorption performance variations are seen even for small changes in the resonator neck length. Reducing the neck-to-cavity expansion ratio is found to decrease the resonator's sound absorption when the expansion ratio is low. CSC-Imperial PhD Scholarship; ERC Starting Grant, ACOULOMODE (2013-18).

  7. Underwater expansion wave focusing by reflecting at the air interface

    Science.gov (United States)

    Ohtani, K.; Ogawa, T.

    2017-02-01

    This paper reports a preliminarily experimental result of high-speed shadowgraph optical visualization of underwater expansion wave focusing by using a simple two-dimensional wedge model for understanding of shock wave interaction phenomena in simulated biomedical materials. Underwater shock wave generated by detonating a micro-explosive (10 mg silver azide pellet) in a small chamber. The generated underwater shock wave was interacted with a wedge shaped interface between water and air divided by a thin film, and an expansion wave was generated by reflection at the interface. The process of underwater expansion wave generation and focusing phenomena was visualized by shadowgraph method and recorded by ultra-high-speed framing camera. Underwater shock wave was reflected as an expansion wave from the interface between water and air at the both side and focused and then cavitation bubble was created by pressure decreasing at the expansion wave focusing area. The pressure histories were measured simultaneously with high-speed optical visualization by a needle type pressure sensor. At the focusing area, the pressure was decreased rapidly, the negative peak pressure was the lowest.

  8. Infinite S-expansion with ideal subtraction and some applications

    Science.gov (United States)

    Peñafiel, D. M.; Ravera, L.

    2017-08-01

    According to the literature, the S-expansion procedure involving a finite semigroup is valid no matter what the structure of the original Lie (super)algebra is; however, when something about the structure of the starting (super)algebra is known and when certain particular conditions are met, the S-expansion method (with its features of resonance and reduction) is able not only to lead to several kinds of expanded (super)algebras but also to reproduce the effects of the standard as well as the generalized Inönü-Wigner contraction. In the present paper, we propose a new prescription for S-expansion, involving an infinite abelian semigroup S(∞ ) and the subtraction of an infinite ideal subalgebra. We show that the subtraction of the infinite ideal subalgebra corresponds to a reduction. Our approach is a generalization of the finite S-expansion procedure presented in the literature, and it offers an alternative view of the generalized Inönü-Wigner contraction. We then show how to write the invariant tensors of the target (super)algebras in terms of those of the starting ones in the infinite S-expansion context presented in this work. We also give some interesting examples of application on algebras and superalgebras.

  9. Some properties of Riesz means and spectral expansions

    Directory of Open Access Journals (Sweden)

    S. A. Fulling

    1999-03-01

    Full Text Available It is well known that short-time expansions of heat kernels correlate to formal high-frequency expansions of spectral densities. It is also well known that the latter expansions are generally not literally true beyond the first term. However, the terms in the heat-kernel expansion correspond rigorously to quantities called Riesz means of the spectral expansion, which damp out oscillations in the spectral density at high frequencies by dint of performing an average over the density at all lower frequencies. In general, a change of variables leads to new Riesz means that contain different information from the old ones. In particular, for the standard second-order elliptic operators, Riesz means with respect to the square root of the spectral parameter correspond to terms in the asymptotics of elliptic and hyperbolic Green functions associated with the operator, and these quantities contain ``nonlocal'' information not contained in the usual Riesz means and their correlates in the heat kernel. Here the relationship between these two sets of Riesz means is worked out in detail; this involves just classical one-dimensional analysis and calculation, with no substantive input from spectral theory or quantum field theory. This work provides a general framework for calculations that are often carried out piecemeal (and without precise understanding of their rigorous meaning in the physics literature.

  10. k-string tensions and the 1/N expansion

    CERN Document Server

    Greensite, Jeff; Patella, Agostino

    2011-01-01

    We address the question of whether the large-N expansion in pure SU(N) gauge theories requires that k-string tensions must have a power series expansion in 1/N^2, as in the sine law, or whether 1/N contributions are also allowable, as in Casimir scaling. We find that k-string tensions may, in fact, have 1/N corrections, and consistency with the large-N expansion in the open-string sector depends crucially on an exact cancellation, which we will prove, among terms involving odd powers of 1/N in particular combinations of Wilson loops. It is shown how these cancellations are fulfilled, and consistency with the large-N expansion achieved, in a concrete example, namely, strong-coupling lattice gauge theory with the heat-kernel action. This is a model which has both a 1/N^2 expansion and Casimir scaling of the k-string tensions. Analysis of the closed string channel in this model confirms our conclusions, and provides further insights into the large-N dependence of energy eigenstates and eigenvalues.

  11. Urban Land Expansion and Spatial Dynamics in Globalizing Shanghai

    Directory of Open Access Journals (Sweden)

    Han Li

    2014-12-01

    Full Text Available Urban land expansion in China has attracted considerable scholarly attention. However, more work is needed to apply spatial modeling to understanding the mechanisms of urban growth from both institutional and physical perspectives. This paper analyzes urban expansion in Shanghai and its development zones (DZs. We find that, as nodes of global-local interface, the DZs are the most significant components of urban growth in Shanghai, and major spatial patterns of urban expansion in Shanghai are infilling and edge expansion. We apply logistic regression, geographically weighted logistic regression (GWLR and spatial regime regression to investigate the determinants of urban land expansion including physical conditions, state policy and land development. Regressions reveal that, though the market has been an important driving force in urban growth, the state has played a predominant role through the implementation of urban planning and the establishment of DZs to fully capitalize on globalization. We also find that differences in urban growth dynamics exist between the areas inside and outside of the DZs. Finally, this paper discusses policies to promote sustainable development in Shanghai.

  12. EXPANSION OF SOLIDARY ECONOMY IN THE SOUTH OF BRAZIL

    Directory of Open Access Journals (Sweden)

    Bolívar Alencar Ribeiro

    2013-03-01

    Full Text Available This work was based in a detailed analysis of supplied informations by SIES/MTE, the major database about Solidary Economy in Brazil. The object of this study was the expansion of the solidary economy in the south region of Brazil. This way the general objective to understand and to analyze the expansion of the solidary economy in the south region of Brazil. Thereby search to demonstrate the considerable expansion of activities under the principles of Economics Solidary, this occured on the crisis of formal employment in the decade of 1990, and your apex of growth after the year 2000, when this began to configure how public policy at national. This expansion it was given of differentiated form in Rio Grande do Sul state in general and in pioneering municipalities in the actions that involved the Solidary Economy. Had been considered as hypotheses for this expansion the actions of support entities and the implantation of public politics of support the solidary economy. The research it showed that existence of entities of support, governmental actions,organization capacity of the involved ones beyond the accumulation of experiences is that propitiates matureness of the joint around the solidary economy and induces the creation of public politics of support.

  13. An analytical model for the assessment of airline expansion strategies

    Directory of Open Access Journals (Sweden)

    Mauricio Emboaba Moreira

    2014-01-01

    Full Text Available Purpose: The purpose of this article is to develop an analytical model to assess airline expansion strategies by combining generic business strategy models with airline business models. Methodology and approach: A number of airline business models are examined, as are Porter’s (1983 industry five forces that drive competition, complemented by Nalebuff/ Brandenburger’s  (1996 sixth force, and the basic elements of the general environment in which the expansion process takes place.  A system of points and weights is developed to create a score among the 904,736 possible combinations considered. The model’s outputs are generic expansion strategies with quantitative assessments for each specific combination of elements inputted. Originality and value: The analytical model developed is original because it combines for the first time and explicitly elements of the general environment, industry environment, airline business models and the generic expansion strategy types. Besides it creates a system of scores that may be used to drive the decision process toward the choice of a specific strategic expansion path. Research implications: The analytical model may be adapted to other industries apart from the airline industry by substituting the element “airline business model” by other industries corresponding elements related to the different specific business models.

  14. Advanced methodology for generation expansion planning including interconnected systems

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, M.; Yokoyama, R.; Yasuda, K. [Tokyo Metropolitan Univ. (Japan); Sasaki, H. [Hiroshima Univ. (Japan); Ogimoto, K. [Electric Power Development Co. Ltd., Tokyo (Japan)

    1994-12-31

    This paper reviews advanced methodology for generation expansion planning including interconnected systems developed in Japan, putting focus on flexibility and efficiency in a practical application. First, criteria for evaluating flexibility of generation planning considering uncertainties are introduced. Secondly, the flexible generation mix problem is formulated as a multi-objective optimization with more than two objective functions. The multi-objective optimization problem is then transformed into a single objective problem by using the weighting method, to obtain the Pareto optimal solution, and solved by a dynamics programming technique. Thirdly, a new approach for electric generation expansion planning of interconnected systems is presented, based on the Benders Decomposition technique. That is, large scale generation problem constituted by the general economic load dispatch problem, and several sub problems which are composed of smaller scale isolated system generation expansion plans. Finally, the generation expansion plan solved by an artificial neural network is presented. In conclusion, the advantages and disadvantages of this method from the viewpoint of flexibility and applicability to practical generation expansion planning are presented. (author) 29 refs., 10 figs., 4 tabs.

  15. Expansion/Facemask Treatment of an Adult Class III Malocclusion

    Directory of Open Access Journals (Sweden)

    Gregory W. Jackson

    2014-01-01

    Full Text Available The orthodontic treatment of class III malocclusion with a maxillary deficiency is often treated with maxillary protraction with or without expansion. Skeletal and dental changes have been documented which have combined for the protraction of the maxilla and the correction of the class III malocclusion. Concerning the ideal time to treat a developing class III malocclusion, studies have reported that, although early treatment may be the most effective, face mask therapy can provide a viable option for older children as well. But what about young adults? Can the skeletal and dental changes seen in expansion/facemask therapy in children and adolescents be demonstrated in this age group as well, possibly eliminating the need for orthodontic dental camouflage treatment or orthognathic surgery? A case report is presented of an adult class III malocclusion with a Class III skeletal pattern and maxillary retrusion. Treatment was with nonextraction, comprehensive edgewise mechanics with slow maxillary expansion with a bonded expander and protraction facemask.

  16. Expansion/Facemask Treatment of an Adult Class III Malocclusion.

    Science.gov (United States)

    Jackson, Gregory W; Kravitz, Neal D

    2014-01-01

    The orthodontic treatment of class III malocclusion with a maxillary deficiency is often treated with maxillary protraction with or without expansion. Skeletal and dental changes have been documented which have combined for the protraction of the maxilla and the correction of the class III malocclusion. Concerning the ideal time to treat a developing class III malocclusion, studies have reported that, although early treatment may be the most effective, face mask therapy can provide a viable option for older children as well. But what about young adults? Can the skeletal and dental changes seen in expansion/facemask therapy in children and adolescents be demonstrated in this age group as well, possibly eliminating the need for orthodontic dental camouflage treatment or orthognathic surgery? A case report is presented of an adult class III malocclusion with a Class III skeletal pattern and maxillary retrusion. Treatment was with nonextraction, comprehensive edgewise mechanics with slow maxillary expansion with a bonded expander and protraction facemask.

  17. Tissue expansion for correction of baldness in aplasia cutis congenita.

    Science.gov (United States)

    Beekmans, S J A; don Griot, J P W; Niessen, F B; Mulder, J W

    2009-05-01

    Aplasia cutis is a congenital absence of the skin, usually presenting on the scalp. In 20% of all cases, part of the skull is also absent. A residual area of baldness may still be present some years after surgical or conservative treatment. It is possible to excise the scarred hairless region and cover that area with expanded hair-bearing skin from the rest of the skull. We present three patients who underwent tissue expansion and discuss the indications and pitfalls of this procedure. Tissue expansion can be used to cover a residual alopecia defect in young children with aplasia cutis congenita and associated bone abnormalities. The quality of the bone appears to be normal in our three patients. We demonstrate that even in young children with aplasia cutis and an underlying bony defect, tissue expansion is a safe and effective modality as a second stage reconstruction procedure.

  18. Surgically assisted rapid palatal expansion: a literature review.

    Science.gov (United States)

    Suri, Lokesh; Taneja, Parul

    2008-02-01

    Transverse maxillomandibular discrepancies are a major component of several malocclusions. Orthopedic and orthodontic forces are used routinely to correct a maxillary transverse deficiency (MTD) in a young patient. Correction of MTD in a skeletally mature patient is more challenging because of changes in the osseous articulations of the maxilla with the adjoining bones. Surgically assisted rapid palatal expansion (SARPE) has gradually gained popularity as a treatment option to correct MTD. It allows clinicians to achieve effective maxillary expansion in a skeletally mature patient. The use of SARPE to treat MTD decreases unwanted effects of orthopedic or orthodontic expansion. Our aim in this article is to present a comprehensive review of the literature, including indications, diagnosis, guidelines for case selection, a brief overview of the surgical techniques, orthodontic considerations, complications, risks, and limitations of SARPE to better aid the clinician in the management of MTD in skeletally mature patients.

  19. Hydrodynamic Expansion of Pellicles Caused by e-Beam Heating

    CERN Document Server

    Ho, D

    2000-01-01

    Placing a pellicle in front of a x-ray converter target for radiographic applications can confine the backstreaming ions and target plasma to a shorter channel so that the cumulative effect on e-beam focusing is reduced. The pellicle is subject to heating by e-beam since the pellicle is placed upstream of the target. The calculation of the hydrodynamic expansion, caused by the heating, using the radiation hydrodynamics code LASNEX is presented in this report. Calculations show that mylar pellicles disintegrate at the end of a multi-pulse intense e-beam while beryllium and carbon pellicles remain intact. The expansions for the kapton-carbon multi-layered targets are also examined. Hydrodynamic expansions for pellicles with various e-beam spot radii are calculated for DARHT-II beam parameters. All the simulation results indicate that the backstreaming ions can be stopped.

  20. Transmission expansion in an oligopoly considering generation investment equilibrium

    DEFF Research Database (Denmark)

    Taheri, S. Saeid; Kazempour, Jalal; Seyedshenava, Seyedjalal

    2017-01-01

    Transmission expansion planning (TEP) is a sophisticated decision-making problem, especially in an oligopolistic electricity market in which a number of strategic (price-maker) producers compete together. A transmission system planner, who is in charge of making TEP decisions, requires considering...... the future generation investment actions. However, in such an oligopolistic market, each producer makes its own strategic generation investment decisions. This motivates the transmission system planner to consider the generation investment decision-making problem of all producers within its TEP model....... This paper proposes a tri-level TEP decision-making model to be solved by the transmission system planner, whose objective is to maximize the social welfare of the market minus the expansion costs, and whose constraints are the transmission expansion limits as well as the generation investment equilibrium...

  1. A Quantum Query Expansion Approach for Session Search

    Directory of Open Access Journals (Sweden)

    Peng Zhang

    2016-04-01

    Full Text Available Recently, Quantum Theory (QT has been employed to advance the theory of Information Retrieval (IR. Various analogies between QT and IR have been established. Among them, a typical one is applying the idea of photon polarization in IR tasks, e.g., for document ranking and query expansion. In this paper, we aim to further extend this work by constructing a new superposed state of each document in the information need space, based on which we can incorporate the quantum interference idea in query expansion. We then apply the new quantum query expansion model to session search, which is a typical Web search task. Empirical evaluation on the large-scale Clueweb12 dataset has shown that the proposed model is effective in the session search tasks, demonstrating the potential of developing novel and effective IR models based on intuitions and formalisms of QT.

  2. Exact semiclassical expansions for one-dimensional quantum oscillators

    Energy Technology Data Exchange (ETDEWEB)

    Delabaere, E. [UMR CNRS J. A. Dieudonne No. 6621, University of Nice, 06108 Nice Cedex 2 (France); Dillinger, H.; Pham, F. [University of Nice, Department of Maths, UMR CNRS J.A. Dieudonne No. 6621, 06108 Nice Cedex 2 (France)

    1997-12-01

    A set of rules is given for dealing with WKB expansions in the one-dimensional analytic case, whereby such expansions are not considered as approximations but as exact encodings of wave functions, thus allowing for analytic continuation with respect to whichever parameters the potential function depends on, with an exact control of small exponential effects. These rules, which include also the case when there are double turning points, are illustrated on various examples, and applied to the study of bound state or resonance spectra. In the case of simple oscillators, it is thus shown that the Rayleigh{endash}Schr{umlt o}dinger series is Borel resummable, yielding the exact energy levels. In the case of the symmetrical anharmonic oscillator, one gets a simple and rigorous justification of the Zinn-Justin quantization condition, and of its solution in terms of {open_quotes}multi-instanton expansions.{close_quotes} {copyright} {ital 1997 American Institute of Physics.}

  3. Atom-partitioned multipole expansions for electrostatic potential boundary conditions

    Energy Technology Data Exchange (ETDEWEB)

    Lee, M., E-mail: michael.s.lee131.civ@mail.mil [Simulation Sciences Branch, U.S. Army Research Laboratory, Aberdeen Proving Ground, MD 21005 (United States); Leiter, K. [Simulation Sciences Branch, U.S. Army Research Laboratory, Aberdeen Proving Ground, MD 21005 (United States); Eisner, C. [Secure Mission Solutions, a Parsons Company (United States); Simulation Sciences Branch, U.S. Army Research Laboratory, Aberdeen Proving Ground, MD 21005 (United States); Knap, J. [Simulation Sciences Branch, U.S. Army Research Laboratory, Aberdeen Proving Ground, MD 21005 (United States)

    2017-01-01

    Applications such as grid-based real-space density functional theory (DFT) use the Poisson equation to compute electrostatics. However, the expected long tail of the electrostatic potential requires either the use of a large and costly outer domain or Dirichlet boundary conditions estimated via multipole expansion. We find that the oft-used single-center spherical multipole expansion is only appropriate for isotropic mesh domains such as spheres and cubes. In this work, we introduce a method suitable for high aspect ratio meshes whereby the charge density is partitioned into atomic domains and multipoles are computed for each domain. While this approach is moderately more expensive than a single-center expansion, it is numerically stable and still a small fraction of the overall cost of a DFT calculation. The net result is that when high aspect ratio systems are being studied, form-fitted meshes can now be used in lieu of cubic meshes to gain computational speedup.

  4. TDHF simulation of the expansion of abraded nuclei

    Energy Technology Data Exchange (ETDEWEB)

    Lacroix, D.; Chomaz, Ph

    1998-03-01

    A recent interpretation of the caloric curve based on the expansion of the abraded spectator nuclear is re-analysed in the framework of the Time Dependent Hartree Fock (TDHF) evolution. It is shown that the TDHF dynamics can not be reduced to a single monopolar collective motion at moderate energy. The inclusion of other important collective degrees of freedom may lead to the dynamical creation of hollow structure. Then, low density regions could be locally reached after a long time by the creation of these exotic density profiles. The TDHF simulations do not confirm conclusions made when using an monopolar isentropic expansion. In particular the systematic of the minimum density reached during the expansion (the so-called turning points) appears to be different. (author) 20 refs.

  5. Space Creation Mechanism during the Expansion of Universe

    Directory of Open Access Journals (Sweden)

    Emre Dil

    2016-01-01

    Full Text Available We propose a novel mechanism related to the expansion of universe. Recently Verlinde’s proposal has been applied to the deformed bosons being a candidate for the dark energy constituents, since the negative pressure of the deformed bosons. The expansion of universe is dependent on the dark energy and implies a creation of space; we admit that the space creation mechanism is related to the deformed bosons and so is the dark energy. In order to relate the dark energy and the mechanism for creation of space, we consider Verlinde’s proposal including the Holographic principle for emergence of space, which was recently applied to the deformed bosons. To check the validity of our mechanism, we calculate the ratio of the size of universe before and after the expansion and compare the results with the observational data. We find that the results are consistent with each other and infer that the proposed mechanism works correctly.

  6. Cluster expansion for ground states of local Hamiltonians

    Directory of Open Access Journals (Sweden)

    Alvise Bastianello

    2016-08-01

    Full Text Available A central problem in many-body quantum physics is the determination of the ground state of a thermodynamically large physical system. We construct a cluster expansion for ground states of local Hamiltonians, which naturally incorporates physical requirements inherited by locality as conditions on its cluster amplitudes. Applying a diagrammatic technique we derive the relation of these amplitudes to thermodynamic quantities and local observables. Moreover we derive a set of functional equations that determine the cluster amplitudes for a general Hamiltonian, verify the consistency with perturbation theory and discuss non-perturbative approaches. Lastly we verify the persistence of locality features of the cluster expansion under unitary evolution with a local Hamiltonian and provide applications to out-of-equilibrium problems: a simplified proof of equilibration to the GGE and a cumulant expansion for the statistics of work, for an interacting-to-free quantum quench.

  7. Coupling of solute transport and cell expansion in pea stems

    Science.gov (United States)

    Schmalstig, J. G.; Cosgrove, D. J.

    1990-01-01

    As cells expand and are displaced through the elongation zone of the epicotyl of etiolated pea (Pisum sativum L. var Alaska) seedlings, there is little net dilution of the cell sap, implying a coordination between cell expansion and solute uptake from the phloem. Using [14C] sucrose as a phloem tracer (applied to the hypogeous cotyledons), the pattern of label accumulation along the stem closely matched the growth rate pattern: high accumulation in the growing zone, little accumulation in nongrowing regions. Several results suggest that a major portion of phloem contents enters elongating cells through the symplast. We propose that the coordination between phloem transport and cell expansion is accomplished via regulatory pathways affecting both plasmodesmata conductivity and cell expansion.

  8. Generation expansion planning in a competitive electric power industry

    Science.gov (United States)

    Chuang, Angela Shu-Woan

    This work investigates the application of non-cooperative game theory to generation expansion planning (GEP) in a competitive electricity industry. We identify fundamental ways competition changes the nature of GEP, review different models of oligopoly behavior, and argue that assumptions of the Cournot model are compatible with GEP. Applying Cournot theory of oligopoly behavior, we formulate a GEP model that may characterize expansion in the new competitive regime, particularly in pool-dominated generation supply industries. Our formulation incorporates multiple markets and is patterned after the basic design of the California ISO/PX system. Applying the model, we conduct numerical experiments on a test system, and analyze generation investment and market participation decisions of different candidate expansion units that vary in costs and forced outage rates. Simulations are performed under different scenarios of competition. In particular, we observe higher probabilistic measures of reliability from Cournot expansion compared to the expansion plan of a monopoly with an equivalent minimum reserve margin requirement. We prove several results for a subclass of problems encompassed by our formulation. In particular, we prove that under certain conditions Cournot competition leads to greater total capacity expansion than a situation in which generators collude in a cartel. We also show that industry output after introduction of new technology is no less than monopoly output. So a monopoly may lack sufficient incentive to introduce new technologies. Finally, we discuss the association between capacity payments and the issue of pricing reliability. And we derive a formula for computing ideal capacity payment rates by extending the Value of Service Reliability technique.

  9. Glass ceramics for sealing to high-thermal-expansion metals

    Energy Technology Data Exchange (ETDEWEB)

    Wilder, Jr., J. A.

    1980-10-01

    Glass ceramics were studied, formulated in the Na/sub 2/O CaO.P/sub 2/O/sub 5/, Na/sub 2/O.BaOP/sub 2/O/sub 5/, Na/sub 2/O.Al/sub 2/O/sub 3/.P/sub 2/O/sub 5/, and Li/sub 2/O.BaO.P/sub 2/O/sub 5/ systems to establish their suitability for sealing to high thermal expansion metals, e.g. aluminum, copper, and 300 series stainless steels. Glass ceramics in Na/sub 2/O.CaO.P/sub 2/O/sub 5/ and Na/sub 2/O.BaO.P/sub 2/O/sub 5/ systems have coefficients of thermal expansion in the range 140 x 10/sup -1/ per /sup 0/C less than or equal to ..cap alpha.. less than or equal to 225 x 10/sup -7/ per /sup 0/C and fracture toughness values generally greater than those of phosphate glasses; they are suitable for fabricating seals to high thermal expansion metals. Crystal phases include NaPo/sub 3/, (NaPO/sub 3/)/sub 3/, NaBa(PO/sub 3/)/sub 3/, and NaCa(PO/sub 3/)/sub 3/. Glass ceramics formed in the Na/sub 2/O.Al/sub 2/O/sub 3/.P/sub 2/O/sub 5/ systems have coefficients of thermal expansion greater than 240 x 10/sup -7/ per /sup 0/C, but they have extensive microcracking. Due to their low thermal expansion values (..cap alpha.. less than or equal to 120 x 10/sup -7/ per /sup 0/C), glass ceramics in the Li/sub 2/O.BaO.P/sub 2/O/sub 5/ system are unsuitable for sealing to high thermal expansion metals.

  10. Expansion with respect to resonance functions in nuclear physics problems

    Energy Technology Data Exchange (ETDEWEB)

    Gareev, F.A.; Bang, J.

    1980-07-01

    A study is made of the pole expansion (in accordance with Mittag-Leffler's theorem) of the wave functions, scattering amplitudes, and Green's functions at positive energies. The general form of these expansions is obtained and discussed for finite-range potentials and also for a Coulomb repulsive potential. A number of examples of the use of the method are considered in structure calculations including continuum states, and the limits of applicability of other approximate methods used in such calculations are established.

  11. Glass-to-metal seals comprising relatively high expansion metals

    Science.gov (United States)

    Hirayama, C. (Inventor)

    1974-01-01

    A glass suitable for glass-to-metal seals that has a resistance to attack by moisture and a high coefficient of linear thermal expansion is introduced. Linear expansion covers the range from 12 to 14 x 10 to the minus 6 C between room temperature and 500 C. The glass is essentially composed of, by molar percent, about 9% of K2O, about 10% of Na2O, about 70% of SiO2, about 6% Al2O3, and about 5% of MgO.

  12. Theory of low-temperature thermal expansion of glasses

    Science.gov (United States)

    Galperin, Yu. M.; Gurevich, V. L.; Parshin, D. A.

    1985-11-01

    We have developed a theory of low-temperature thermal expansion of glasses explaining a number of existing experimental data. We assume that thermal expansion, like many other low-temperature properties of glasses, is determined by associated two-level systems (TLS's) this concept has been introduced to explain these properties by Anderson, Halperin, and Varma and by Phillips. Our theory is based on the Karpov-Klinger-Ignat'ev model of two-level systems in glasses. The deformation potential of the TLS's is calculated. We have shown that it consists of two parts: The larger part (of the order of 0.3 eV) is responsible for the observed transport properties of glasses; however, it does not contribute to the thermal expansion of glasses. The latter is caused by a relatively small second part of the deformation potential which is, within logarithmic accuracy, proportional to the TLS's interlevel spacing E. This is why at low temperatures the coefficient of thermal expansion of glasses is approximately a linear function of the temperature. Its sign is determined by a microscopic structure of the TLS. We have calculated the Grüneisen parameter Γ. It appears to be of the order of (scrEa/ħωD)2/3~=100, where scrEa is an energy of the order of 30 eV and ωD is the Debye frequency. Such large values of Γ are connected with the softness of local anharmonic potentials that produce the TLS's in glasses. Our principal result is the dependence of the coefficient of thermal expansion α on the time of experiment, τexpt. It is shown that if α<0, then after heating glass it is at first contracted and afterwards, after the time about 10-8 sec (at T=0.3 K), a slow expansion begins. At τexpt~=1 sec the parameter Γ can have the absolute value of about (1/3) of that at τexpt~=10-8 sec. Such behavior of the thermal expansion coefficient is due to the fact that the contribution of the TLS's with large relative tunnel splitting (Δ0/E~=1) is negative while that of the TLS's with

  13. Merchant electricity transmission expansion: A European case study

    Energy Technology Data Exchange (ETDEWEB)

    Kristiansen, T. [RBS Sempra Commodities, 155 Bishopsgate, London EC2M3TZ (United Kingdom); Rosellon, J. [Centro de Investigacion y Docencia Economicas (CIDE), Division de Economia, Carretera Mexico-Toluca 3655, Lomas de Santa Fe, 01210 Mexico D.F. (Mexico); German Institute for Economic Research (DIW Berlin), Mohrenstrasse 58, 10117, Berlin (Germany)

    2010-10-15

    We apply a merchant transmission model to the trilateral market coupling (TLC) arrangement among the Netherlands, Belgium and France as an example, and note that it could further be applied to other market splitting or coupling of Europe's different national power markets. In this merchant framework the system operator allocates financial transmission rights (FTRs) to investors in transmission expansion based upon their preferences, and revenue adequacy. The independent system operator (ISO) preserves some proxy FTRs to manage potential negative externalities that may result from expansion projects. This scheme could help European market coupling arrangements attract additional investment. (author)

  14. Process Investigation of Tube Expansion by Gas Detonation

    OpenAIRE

    Bach, F.-W.; Beerwald, C.; Brosius, A.; Gershteyn, G.; Hermes, M.; Kleiner, M.; Olivier, H.; Weber, M.

    2006-01-01

    The present paper deals with the expansion of tubes by direct application of gas detonation waves, i.e. the gas is both pressure medium and energy source. After an introduction to gas detonation forming, measurements of the motion process and the internal pressures are presented. Results of free expansion and of forming into a die are thoroughly studied and compared to the results of quasi-static burst tests and hydroforming. Using pure aluminum Al99.5 and a medium strength alloy AlMgSi1, ...

  15. Free and constrained expansion of fire ant aggregations

    Science.gov (United States)

    Fernandez-Nieves, Alberto; Anderson, Caleb

    We revisit the classical free and constrained expansion of ideal gases with fire ant aggregations. We use rectangular parallel plates to confine fire ants to two-dimensions and watch how these expand when the plates are horizontal or when these are vertical. In the first case, the ants expand in a rather disorganized fashion, while in the second case, when there is work involved, the expansion is rather organized. The behavior is reminiscent of what is expected from the so called reversible process theorems of classical thermodynamics despite the ant aggregation is intrinsically out of equilibrium. This talk will focus on these results and in related observations in the same experimental setting.

  16. Non tumoral intracranial expansive processes: clinical-tomographic correlation

    Directory of Open Access Journals (Sweden)

    Patricia Campos

    1991-09-01

    Full Text Available Presentation of clinical-tomographic correlation in 111 cases of non tumoral intracranial expansive processes seen between 1984-1988 in the Hospital Cayetano Heredia (Lima, Peru. Emphasis is given fundamentally to: (1 the importance of stablishing the or-ganicity of partial and late epilepsy; (2 the high incidence rate of inflammatory infectious processes with CNS compromise in underdeveloping countries; (3 the necessity of making public the importance of two parisitic diseases in the differential diagnosis of non tumoral intracranial expansive processes: free living amebiasis, and toxoplasmosis (especially in association with AIDS.

  17. Dynamic Crossover and Mutation Genetic Algorithm Based on Expansion Sampling

    Science.gov (United States)

    Dong, Min; Wu, Yan

    The traditional genetic algorithm gets in local optimum easily, and its convergence rate is not satisfactory. So this paper proposed an improvement, using dynamic cross and mutation rate cooperate with expansion sampling to solve these two problems. The expansion sampling means the new individuals must compete with the old generation when create new generation, as a result, the excellent half ones are selected into the next generation. Whereafter several experiments were performed to compare the proposed method with some other improvements. The results are satisfactory. The experiment results show that the proposed method is better than other improvements at both precision and convergence rate.

  18. High-temperature series expansions for random Potts models

    Directory of Open Access Journals (Sweden)

    M.Hellmund

    2005-01-01

    Full Text Available We discuss recently generated high-temperature series expansions for the free energy and the susceptibility of random-bond q-state Potts models on hypercubic lattices. Using the star-graph expansion technique, quenched disorder averages can be calculated exactly for arbitrary uncorrelated coupling distributions while keeping the disorder strength p as well as the dimension d as symbolic parameters. We present analyses of the new series for the susceptibility of the Ising (q=2 and 4-state Potts model in three dimensions up to the order 19 and 18, respectively, and compare our findings with results from field-theoretical renormalization group studies and Monte Carlo simulations.

  19. Compressibility and thermal expansion of cubic silicon nitride

    DEFF Research Database (Denmark)

    Jiang, Jianzhong; Lindelov, H.; Gerward, Leif

    2002-01-01

    The compressibility and thermal expansion of the cubic silicon nitride (c-Si3N4) phase have been investigated by performing in situ x-ray powder-diffraction measurements using synchrotron radiation, complemented with computer simulations by means of first-principles calculations. The bulk...... compressibility of the c-Si3N4 phase originates from the average of both Si-N tetrahedral and octahedral compressibilities where the octahedral polyhedra are less compressible than the tetrahedral ones. The origin of the unit cell expansion is revealed to be due to the increase of the octahedral Si-N and N-N bond...

  20. R316-million Richards Bay Coal Terminal expansions underway

    Energy Technology Data Exchange (ETDEWEB)

    1990-10-01

    Fabrication is underway on items critical to the R316-million expansion programme newly embarked upon by Richards Bay Coal Terminal (RBCT, South Africa), according to project manager SEMTEC. The expansion will increase the capacity of RBTC from 44 million tons of export quality coal a year to 53-million tons. The scope of work includes the design and fabrication of a tandem tippler, a stacker reclaimer, and new conveyors as well as upgrading the existing conveyor, terminal control and railway system and the supply of new locomotives.

  1. Thermal expansion method for lining tantalum alloy tubing with tungsten

    Science.gov (United States)

    Watson, G. K.; Whittenberger, J. D.; Mattson, W. F.

    1973-01-01

    A differential-thermal expansion method was developed to line T-111 (tantalum - 8 percent tungsten - 2 percent hafnium) tubing with a tungsten diffusion barrier as part of a fuel element fabrication study for a space power nuclear reactor concept. This method uses a steel mandrel, which has a larger thermal expansion than T-111, to force the tungsten against the inside of the T-111 tube. Variables investigated include lining temperature, initial assembly gas size, and tube length. Linear integrity increased with increasing lining temperature and decreasing gap size. The method should have more general applicability where cylinders must be lined with a thin layer of a second material.

  2. Langmuir probe study of plasma expansion in pulsed laser ablation

    DEFF Research Database (Denmark)

    Hansen, T.N.; Schou, Jørgen; Lunney, J.G.

    1999-01-01

    Langmuir probes were used to monitor the asymptotic expansion of the plasma produced by the laser ablation of a silver target in a vacuum. The measured angular and temporal distributions of the ion flux and electron temperature were found to be in good agreement with the self-similar isentropic a...... and adiabatic solution of the gas dynamics equations describing the expansion. The value of the adiabatic index gamma was about 1.25, consistent with the ablation plume being a low temperature plasma....

  3. THE EXPANSION OF THE RITZ-CARLTON® ON FOREIGN MARKETS

    OpenAIRE

    Mihai-Răzvan DOBAI

    2016-01-01

    The spreading of globalization drives the companies’ pursuit to expand on foreign markets for various reasons. In this paper it will be analysed the expansion on non-US markets of the Ritz-Carlton®, a hotel company with tradition, being known for its services quality. The analysis takes into consideration the opening year of the hotels in the Latin American, European, Middle Eastern, Central and South Asian and AsiaPacific market, trying to correlate the expansion on certain areas and l...

  4. Expansion of a spherical dust gas -- the cosmological conundrum

    CERN Document Server

    Müller, Ingo

    2015-01-01

    The universe is viewed as a dust gas filling a sphere and floating in infinite empty space. Einstein's gravitational equations are applied to this case together with appropriate boundary values. The equations are solved for initial conditions chosen so as to describe the observed Hubble diagram. We find that the solution is not unique so that more astronomical observations are needed. However, those solutions which were found do not exhibit an accelerated expansion of the universe, nor -- obviously then -- do they need the notion of a dark energy driving such an expansion. We present this study as an alternative to the prevailing Robertson-Walker cosmology.

  5. On q-extension of Laurent expansion with applications

    Directory of Open Access Journals (Sweden)

    Ahmed Salem

    2014-01-01

    Full Text Available In this article, Cauchy’s integral formula for nth q-derivative of analytic functions is established and used to introduce a new proof to q-Taylor series by means of using the residue calculus in the complex analysis. Some theorems related to this formula are presented. A q-extension of a Laurent expansion is derived and proved by means of using Cauchy’s integral formula for a function, which is analytic on a ring-shaped region bounded by two concentric circles. Three illustrative examples are presented to be as applications for a q-Laurent expansion.

  6. Generation Expansion Planning Considering Integrating Large-scale Wind Generation

    DEFF Research Database (Denmark)

    Zhang, Chunyu; Ding, Yi; Østergaard, Jacob

    2013-01-01

    Generation expansion planning (GEP) is the problem of finding the optimal strategy to plan the Construction of new generation while satisfying technical and economical constraints. In the deregulated and competitive environment, large-scale integration of wind generation (WG) in power system has...... necessitated the inclusion of more innovative and sophisticated approaches in power system investment planning. A bi-level generation expansion planning approach considering large-scale wind generation was proposed in this paper. The first phase is investment decision, while the second phase is production...

  7. Expansion coefficients of scattering parameters in quantum thermodynamic perturbation theory

    Energy Technology Data Exchange (ETDEWEB)

    Buendia, E.; Guardiola, R. (Departamento de Fisica Moderna, Universidad de Granada Granada, Spain, 18071 (ES)); De Llano, M. (Physics Department, North Dakota State University, Fargo, North Dakota 58105)

    1989-07-01

    We tabulate the expansion coefficients of various scattering parameters associated with several interparticle pair potentials used in the quantum thermodynamic perturbation theory of strongly coupled, many-particle substances. The expansion is in powers or the attractive part of the pair potential. The potential is divided into repulsive and attractive parts according to several methods in vogue both in classical and in quantum equation-of-state studies of condensed-matter systems. Results are reported for several interparticle potentials of helium-3 and -4 atoms, of the three electron spin-polarized isotopes of atomic hydrogen, and of the nucleon.

  8. Multi-year expansion planning of large transmission networks

    Energy Technology Data Exchange (ETDEWEB)

    Binato, S.; Oliveira, G.C. [Centro de Pesquisas de Energia Eletrica (CEPEL), Rio de Janeiro, RJ (Brazil)

    1994-12-31

    This paper describes a model for multi-year transmission network expansion to be used in long-term system planning. The network is represented by a linearized (DC) power flow and, for each year, operation costs are evaluated by a linear programming (LP) based algorithm that provides sensitivity indices for circuit reinforcements. A Backward/Forward approaches is proposed to devise an expansion plan over the study period. A case study with the southeastern Brazilian system is presented and discussed. (author) 18 refs., 5 figs., 1 tab.

  9. Orthogonal Expansions for VIX Options Under Affine Jump Diffusions

    DEFF Research Database (Denmark)

    Barletta, Andrea; Nicolato, Elisa

    2017-01-01

    In this work we derive new closed–form pricing formulas for VIX options in the jump-diffusion SVJJ model proposed by Duffie et al. (2000). Our approach is based on the classic methodology of approximating a density function with an orthogonal expansion of polynomials weighted by a kernel. Orthogo......In this work we derive new closed–form pricing formulas for VIX options in the jump-diffusion SVJJ model proposed by Duffie et al. (2000). Our approach is based on the classic methodology of approximating a density function with an orthogonal expansion of polynomials weighted by a kernel...

  10. Tight coupling expansion and fully inhomogeneous magnetic fields

    CERN Document Server

    Giovannini, Massimo

    2006-01-01

    The tight coupling expansion, appropriately generalized to include large-scale magnetic fields, allows the estimate of the brightness perturbations of CMB anisotropies for typical wavelengths that are larger than the Hubble radius after matter-radiation equality. After discussing the basic features of the the pre-decoupling initial conditions in the presence of fully inhomogeneous magnetic fields, the tight coupling expansion is studied both analytically and numerically. From the requirement that the amplitudes and phases of Sakharov oscillations are (predominantly) adiabatic and from the inferred value of the plateau in the temperature autocorrelation, the effects of the magnetized contribution can be systematically investigated and constrained.

  11. Contribution of future urbanisation expansion to flood risk changes

    Science.gov (United States)

    Bruwier, Martin; Mustafa, Ahmed; Archambeau, Pierre; Erpicum, Sébastien; Pirotton, Michel; Teller, Jacques; Dewals, Benjamin

    2016-04-01

    The flood risk is expected to increase in the future due to climate change and urban development. Climate change modifies flood hazard and urban development influences exposure and vulnerability to floods. While the influence of climate change on flood risk has been studied widely, the impact of urban development also needs to be considered in a sustainable flood risk management approach. The main goal of this study is the determination of the sensitivity of future flood risk to different urban development scenarios at a relatively short-time horizon in the River Meuse basin in Wallonia (Belgium). From the different scenarios, the expected impact of urban development on flood risk is assessed. Three urban expansion scenarios are developed up to 2030 based on a coupled cellular automata (CA) and agent-based (AB) urban expansion model: (i) business-as-usual, (ii) restrictive and (iii) extreme expansion scenarios. The main factor controlling these scenarios is the future urban land demand. Each urban expansion scenario is developed by considering or not high and/or medium flood hazard zones as a constraint for urban development. To assess the model's performance, it is calibrated for the Meuse River valley (Belgium) to simulate urban expansion between 1990 and 2000. Calibration results are then assessed by comparing the 2000 simulated land-use map and the actual 2000 land-use map. The flood damage estimation for each urban expansion scenario is determined for five flood discharges by overlaying the inundation map resulting from a hydraulic computation and the urban expansion map and by using damage curves and specific prices. The hydraulic model Wolf2D has been extensively validated by comparisons between observations and computational results during flood event .This study focuses only on mobile and immobile prices for urban lands, which are associated to the most severe damages caused by floods along the River Meuse. These findings of this study offers tools to

  12. Thermal Expansion Behavior of Hot-Pressed Engineered Matrices

    Science.gov (United States)

    Raj, S. V.

    2016-01-01

    Advanced engineered matrix composites (EMCs) require that the coefficient of thermal expansion (CTE) of the engineered matrix (EM) matches those of the fiber reinforcements as closely as possible in order to reduce thermal compatibility strains during heating and cooling of the composites. The present paper proposes a general concept for designing suitable matrices for long fiber reinforced composites using a rule of mixtures (ROM) approach to minimize the global differences in the thermal expansion mismatches between the fibers and the engineered matrix. Proof-of-concept studies were conducted to demonstrate the validity of the concept.

  13. Symmetry Switching of Negative Thermal Expansion by Chemical Control.

    Science.gov (United States)

    Senn, Mark S; Murray, Claire A; Luo, Xuan; Wang, Lihai; Huang, Fei-Ting; Cheong, Sang-Wook; Bombardi, Alessandro; Ablitt, Chris; Mostofi, Arash A; Bristowe, Nicholas C

    2016-05-04

    The layered perovskite Ca3-xSrxMn2O7 is shown to exhibit a switching from a material exhibiting uniaxial negative to positive thermal expansion as a function of x. The switching is shown to be related to two closely competing phases with different symmetries. The negative thermal expansion (NTE) effect is maximized when the solid solution is tuned closest to this region of phase space but is switched off suddenly on passing though the transition. Our results show for the first time that, by understanding the symmetry of the competing phases alone, one may achieve unprecedented chemical control of this unusual property.

  14. China's Higher Education Expansion and the Task of Economic Revitalization

    Science.gov (United States)

    Wang, Xiaoyan; Liu, Jian

    2011-01-01

    This paper centers on the expansion from elite to mass higher education in China and its effects on China's economic development. These effects are twofold, including both the immediate influence of expanded enrollment in higher education on China's economy, and the human capital accumulation for the long term. The paper first provides a…

  15. Application of potential harmonic expansion method to BEC ...

    Indian Academy of Sciences (India)

    We adopt the potential harmonics expansion method for an ab initio solution of the many-body system in a Bose condensate containing interacting bosons. Unlike commonly adopted mean-field theories, our method is capable of handling two-body correlation properly. We disregard three- and higher-body correlations.

  16. Quality of potential harmonics expansion method for dilute Bose ...

    Indian Academy of Sciences (India)

    We present and examine an approximate but ab initio many-body approach, viz., potential harmonics expansion method (PHEM), which includes two-body correlations for dilute Bose–Einstein condensates. Comparing the total ground state energy for three trapped interacting bosons calculated in PHEM with the exact ...

  17. A treatment of expansive soil using different additives

    Directory of Open Access Journals (Sweden)

    Bestun J. Nareeman

    2010-11-01

    Full Text Available There are many factors that govern the expansion behavior of soil. The primary factors are a change in water contentand the amount and type of clay size particles in the soil. Other important factors affecting the expansion behavior include the typeof soil (natural or fill, condition of the soil in terms of dry density and moisture content, magnitude of the surcharge pressure,and amount of no expansive material such as gravel or cobble size particles.In this paper, a swelling soil from the site Hamamuk earth dam, which is located in Koya town north of Iraq, is treated by fourtypes of additives; cement, steel fibers, gasoline fuel and injection by cement grout.The treatment of the expansive soil with 5 % of cement or steel fibers or the injection with cement grout revealed a betterimprovement while 4 % of gasoline oil is sufficient to reveal the optimum treatment by this material. The angle of internal friction is notaffected by the treatment while the cohesion between particles is slightly affected by these additives due to a change in the adhesionbetween the additive and soil particles.

  18. Expansion and Harvesting of hMSC-TERT

    DEFF Research Database (Denmark)

    Weber, Christian; Pohl, Sebastian; Pörtner, Ralf

    2007-01-01

    cultivation and harvesting. Nonporous microcarriers are preferable when the cells need to be kept in viable condition for further applications like tissue engineering or cell therapy. In this study, the qualification of Biosilon, Cytodex 1, Cytodex 3, RapidCell and P102-L for expansion of h...

  19. Effects of rapid maxillary expansion on nasal mucociliary clearance.

    Science.gov (United States)

    Babacan, Hasan; Doruk, Cenk; Uysal, Ismail Onder; Yuce, Salim

    2016-03-01

    To evaluate the changes in nasal mucociliary clearance in orthodontic patients after rapid maxillary expansion (RME) therapy. Forty-two children (25 boys and 17 girls) participated in this study. The RME group consisted of 21 patients (mean age, 13.8 years), who had undergone RME at the initiation of orthodontic treatment. The control group consisted of 21 subjects (mean age, 13.6 years), who were attending the department of orthodontics for active orthodontic treatment. The nasal mucociliary clearance was assessed by the saccharin test. Saccharin transit times (STTs) were measured for each treated subject before expansion (T1), after RME (T2), and after a 3-month retention period (T3). Records were obtained at the same time intervals for each group. The STT decreased significantly in the RME group after expansion and retention (P expansion and retention (P maxillary narrowness and without any history of nasal or systemic disease were within normal limits. However, RME increased the mucociliary clearance in patients who had maxillary narrowness, having positive effects on nasal physiology and increasing nasal cavity volume.

  20. Educational Expansion and Social Mobility in the 20th Century

    Science.gov (United States)

    Breen, Richard

    2010-01-01

    Sociologists consider inequality in educational attainment to be a major cause of inequality between people in their chances of occupying a more advantageous class position. However, there is dispute as to whether educational inequality according to social class background declined during the 20th century. What is not in doubt is the expansion of…

  1. Longitudinal stability of rapid and slow maxillary expansion

    Directory of Open Access Journals (Sweden)

    Fábio Henrique de Sá Leitão Pinheiro

    2014-12-01

    Full Text Available OBJECTIVE: The aim of this retrospective study was to compare the longitudinal stability of two types of posterior crossbite correction: rapid maxillary expansion (RME and slow maxillary expansion (SME.METHODS: Study casts of 90 adolescent patients were assessed for interdental width changes at three different periods: pretreatment (T1, post-treatment (T2 and at least, five years post-retention (T3. Three groups of 30 patients were established according to the treatment received to correct posterior crossbite: Group A (RME, group B (SME and group C (control- Edgewise therapy only. After crossbite correction, all patients received fixed edgewise orthodontic appliances. Paired t-tests and one-way ANOVA were used to identify significant intra and intergroup changes, respectively (P < 0.05.RESULTS: Except for intercanine distance, all widths increased in groups A and B from T1 to T2. In the long-term, the amount of relapse was not different for groups A and B, except for 3-3 widths which showed greater decrease in group A. However, the percentage of clinically relapsed cases of posterior crossbite was similar for rapid and slow maxillary expansion.CONCLUSION: Rapid and slow maxillary expansion showed similar stability in the long-term.

  2. Expanded Polystyrene Re-Expansion Analysis Following Impact Compression

    Science.gov (United States)

    2015-03-04

    USAARL Report No. 2015-08 Expanded Polystyrene Re-Expansion Analysis Following Impact Compression By Mark S. Adams Frederick Brozoski Katie...13 iv This page is intentionally left blank. 1 Introduction Expanded bead polystyrene (EPS) is widely...steep rise in the stress-strain curve and little or no energy attenuation. When compressive stresses are removed, EPS foam will partially re- expand

  3. Patterns of missionary expansion enterprise in Africa: a reflection ...

    African Journals Online (AJOL)

    The core objective of this study is therefore to examine the platforms of missionary expansion enterprise in Africa and the zeal to rout the crescent by unfurling the banner of the cross, which was one of the most inspiring emotions supporting the historical missionary enterprise. Findings showed that the missionaries aroused ...

  4. Quasi-Periodic beta-Expansions and Cut Languages

    Czech Academy of Sciences Publication Activity Database

    Šíma, Jiří; Savický, Petr

    submitted 23.11.2017 (2018) ISSN 0304-3975 R&D Projects: GA ČR GBP202/12/G061 Institutional support: RVO:67985807 Keywords : beta-expansion * quasi-periodicity * Pisot number * cut language * Chomsky hierarchy Subject RIV: IN - Informatics, Computer Science Impact factor: 0.698, year: 2016

  5. Educational Expansion and the Returns to Education: Evidence from Cyprus.

    Science.gov (United States)

    Demetriades, Euripides L.; Psacharopoulos, George

    1987-01-01

    Reports on a study that compared returns to education in the government controlled area of Cyprus as measured in 1974 and again in 1984 after considerable educational expansion. Average salary per year of school is reported for males and females. Overall returns to education decreased during this decade. (CH)

  6. Evidence for expansion of the precuneus in human evolution.

    Science.gov (United States)

    Bruner, Emiliano; Preuss, Todd M; Chen, Xu; Rilling, James K

    2017-03-01

    The evolution of neurocranial morphology in Homo sapiens is characterized by bulging of the parietal region, a feature unique to our species. In modern humans, expansion of the parietal surface occurs during the first year of life, in a morphogenetic stage which is absent in chimpanzees and Neandertals. A similar variation in brain shape among living adult humans is associated with expansion of the precuneus. Using MRI-derived structural brain templates, we compare medial brain morphology between humans and chimpanzees through shape analysis and geometrical modeling. We find that the main spatial difference is a prominent expansion of the precuneus in our species, providing further evidence of evolutionary changes associated with this area. The precuneus is a major hub of brain organization, a central node of the default-mode network, and plays an essential role in visuospatial integration. Together, the comparative neuroanatomical and paleontological evidence suggest that precuneus expansion is a neurological specialization of H. sapiens that evolved in the last 150,000 years that may be associated with recent human cognitive specializations.

  7. Expansion of human cord blood hematopoietic stem cells for transplantation.

    Science.gov (United States)

    Chou, Song; Chu, Pat; Hwang, William; Lodish, Harvey

    2010-10-08

    A recent Science paper reported a purine derivative that expands human cord blood hematopoietic stem cells in culture (Boitano et al., 2010) by antagonizing the aryl hydrocarbon receptor. Major problems need to be overcome before ex vivo HSC expansion can be used clinically. Copyright © 2010 Elsevier Inc. All rights reserved.

  8. Impact of size and temperature on thermal expansion of nanomaterials

    Indian Academy of Sciences (India)

    Abstract. A theoretical method has been discussed to study the size dependency of thermal expan- sion of nanomaterials at higher temperature by considering the surface effect. A thermodynamical analysis of the equation of state (EoS) is studied from the knowledge of thermal expansion of nano- materials based on ...

  9. Effect of high thermal expansion glass infiltration on mechanical ...

    Indian Academy of Sciences (India)

    Administrator

    Abstract. This work studies the effect on the mechanical properties of alumina-10 wt% zirconia (3 mol% yttria stabilized) composite by infiltrating glass of a higher thermal expansion (soda lime glass) on the surface at high temperature. The glass improved the strength of composite at room temperature as well as at high.

  10. Ultra low and negative expansion glass–ceramic materials ...

    Indian Academy of Sciences (India)

    Unknown

    Abstract. Ultra low and negative expansion glass–ceramic materials have been obtained from pyrophyllite and blast furnace slag. The batch composition was modified with the addition of lithium carbonate, hydrated alumina, boric acid and nucleating agent (titania). The batch was melted at 1400°C followed by casting in the.

  11. Hotel industry expansion and sustainable development: A case ...

    African Journals Online (AJOL)

    This article examines how international hotel industry expansion affects sustainable development in the context of least developed countries. The study focuses on power asymmetries in the governance processes of hotel value chains. First it develops a model to analyse these processes. Subsequently this model is used to ...

  12. The nexus of population change, agricultural expansion, landscape ...

    African Journals Online (AJOL)

    It reveals the pattern of change in landscape and how that corresponds to human factors such as increased population, demand for food and consequent expansion in agricultural activity in the modification of Landscape. The period under consideration (1970-2007) witnessed an increase in population size and household ...

  13. Entropy quotients and correct digits in number-theoretic expansions

    NARCIS (Netherlands)

    Bosma, W.; Dajani, K.; Kraaikamp, C.

    2006-01-01

    Expansions that furnish increasingly good approximations to real numbers are usually related to dynamical systems. Although comparing dynamical systems seems difficult in general, Lochs was able in 1964 to relate the relative speed of approximation of decimal and regular continued fraction

  14. Using Taylor Expansions to Prepare Students for Calculus

    Science.gov (United States)

    Lutzer, Carl V.

    2011-01-01

    We propose an alternative to the standard introduction to the derivative. Instead of using limits of difference quotients, students develop Taylor expansions of polynomials. This alternative allows students to develop many of the central ideas about the derivative at an intuitive level, using only skills and concepts from precalculus, and…

  15. Student Mental Models Related to Expansion and Contraction

    Science.gov (United States)

    Kurnaz, Mehmet Altan; Emen, Ayse Yagmur

    2014-01-01

    Following up on the effects of learning environments is essential to learning. The aim of this study was to examine students' mental models related to the concepts of expansion and contraction of materials. The population of the case study consisted of 155 students in a city center in Turkey. The data was gathered using open-ended questions that…

  16. Leaf expansion and biomass allocation in wild wheat (Aegilops) species

    NARCIS (Netherlands)

    Bultynck, L.J.A. (Lieve Jenny Alfons)

    2001-01-01

    Fast expansion of leaf area is an important trait to select for in cereal crop species, especially in arid environments. It is associated with higher crop water-use efficiency, higher above-ground biomass production and yield, and increased competitive ability. This thesis examined the physiological

  17. Higher-order semiclassical energy expansions for potentials with ...

    Indian Academy of Sciences (India)

    Detailed studies were carried out on 1-D systems such as xN (N even) to obtain analytic eigenenergy expansions using WKB methods [6]. For some of these potentials WKB series were summed to all orders to obtain the exact solution [7]. In this paper, we analyse 1-D system |x|α. (α-real) for which we are able to obtain.

  18. Polyglutamine expansion in Drosophila: thermal stress and Hsp70 ...

    Indian Academy of Sciences (India)

    2007-03-15

    Mar 15, 2007 ... Repetitive DNA sequences that encode polyglutamine tracts are prone to expansion and cause highly deleterious phenotypes of neurodegeneration. Despite this tendency, polyglutamine tracts (``polyQs”) are conserved features of eukaryotic genomes. PolyQs are the most frequent protein-coding ...

  19. An improved perfectly matched layer in the eigenmode expansion technique

    DEFF Research Database (Denmark)

    Gregersen, Niels; Mørk, Jesper

    2008-01-01

    When employing the eigenmode expansion technique (EET), parasitic reflections at the boundary of the computational domain can be suppressed by introducing a perfectly matched layer (PML). However, the traditional PML, suffers from an artificial field divergence limiting its usefulness. We propose...

  20. Quantum elasticity of graphene: Thermal expansion coefficient and specific heat

    NARCIS (Netherlands)

    Burmistrov, I.S.; Gornyi, I.V.; Kachorovskii, V.Y.; Katsnelson, M.I.; Mirlin, A.D.

    2016-01-01

    We explore thermodynamics of a quantum membrane, with a particular application to suspended graphene membrane and with a particular focus on the thermal expansion coefficient. We show that an interplay between quantum and classical anharmonicity-controlled fluctuations leads to unusual elastic

  1. 76 FR 81359 - European Larch Canker; Expansion of Regulated Areas

    Science.gov (United States)

    2011-12-28

    ... Management and Budget has waived its review under Executive Order 12866. List of Subjects in 7 CFR Part 301... Animal and Plant Health Inspection Service 7 CFR Part 301 European Larch Canker; Expansion of Regulated... domestic quarantine regulations by expanding the regulated area for European larch canker to include...

  2. Oil palm expansion in Indonesia : serving people, planet and profit?

    NARCIS (Netherlands)

    Susanti, A.

    2016-01-01

    This study aimed to provide a more holistic understanding of how drivers at various levels interplay and continue to feed the expansion of oil palm plantations with its associated land use/cover change (LUCC) particularly deforestation, local economic development and people’s livelihoods. Recent

  3. URBAN EXPANSION AND LOSS OF AGRICULTURAL LAND IN ...

    African Journals Online (AJOL)

    Dr Osondu

    1987-09-23

    Sep 23, 1987 ... IMPLICATIONS FOR AGRICULTURAL BUSINESS. *Njungbwen, E1. Njungbwen, A2. DOI: http://dx.doi.org/10.4314/ejesm.v4i4.9. Received November 8th 2011; accepted December 30th 2011. ABSTRACT. Urban expansion in Uyo Urban Area was analyzed using aerial photographs taken from 1969 – ...

  4. Prony's method and the connected-moments expansion

    Science.gov (United States)

    Fernández, Francisco M.

    2013-02-01

    We show that Prony's method provides the full solution to the nonlinear equations of the connected-moments expansion (CMX). Knowledge of all the parameters in the CMX ansatz is useful for the analysis of the convergence properties of the approach. Prony's method may also be suitable for the calculation of the correlation function for simple quantum-mechanical models.

  5. Simulating Block-Level Urban Expansion for National Wide Cities

    Directory of Open Access Journals (Sweden)

    Ying Long

    2017-05-01

    Full Text Available Large-scale models are generally associated with large spatial modelling units, for example, counties or super grids (several to dozens of km2. Few applied urban models can achieve a large spatial coverage with irregular spatial units due to data availability and computation load. The framework of automatic identification and characterization of blocks developed by Liu and Long (2016 makes such an ideal model possible by establishing the existing urban blocks using road networks and points of interest for very large areas (e.g., a country or a continent. In this study, we develop a mega-vector-blocks cellular automata model (MVB-CA to simulate urban expansion at the block level for 654 Chinese cities. The existing urban blocks in 2012 were used for initiating the MVB-CA and are generated using multi-levelled road networks and ubiquitous points of interest. We then simulate block-based urban expansion of all the cities from 2012 to 2017. The national spatial development strategies of China are discussed extensively by academia and policy makers, while the baseline scenario and other simulated urban expansion scenarios have been tested and compared horizontally. As one of the first block-based urban expansion models at a national scale, its academic contributions, practical applications, and potential biases are also discussed in this paper. The developed MVB-CA using general approaches is also applicable for other counties.

  6. STABILIZATION OF EXPANSIVE SOIL USING BAGASSE ASH & LIME

    African Journals Online (AJOL)

    tekimerry

    on road pavements and building structures. The cost implication of such defects and failures is very high. Many ground improvement techniques have been employed to curb or reduce the severity of the damages caused by expansive soils on civil engineering facilities; among which are lime and cement stabilization [9, 13, ...

  7. Teaching American Diplomacy Using Primary Sources. The Expansion of NATO.

    Science.gov (United States)

    Miles, Michael; Schuster, Heidi

    In this high school U.S. government and U.S. history curriculum unit, students examine in depth the expansion of the North Atlantic Treaty Organization (NATO). Detailed activities are provided to teach students about the origins of NATO, its impact on U.S. foreign policy, and its future directions, particularly the enlargement of NATO in the…

  8. Statistical mechanics of self-gravitating system: Cluster expansion method

    Science.gov (United States)

    Iguchi, O.; Kurokawa, T.; Morikawa, M.; Nakamichi, A.; Sota, Y.; Tatekawa, T.; Maeda, K.-I.

    1999-09-01

    We study statistical mechanics of the self-gravitating system applying the cluster expansion method developed in solid state physics. By summing infinite series of diagrams, we derive a complex free energy whose imaginary part is related to the relaxation time of the system, and a two-point correlation function.

  9. Irrigated land expansion since 1985 in Southern Tunisia

    Science.gov (United States)

    Rodríguez-Caballero, Emilio; Cantón, Yolanda; Moussa, Mohamed; Solé-Benet, Albert

    2017-05-01

    The causes of agricultural land expansion and its impacts on dryland ecosystems such as the oasis regions of Southern Tunisia, are fundamental problems challenging the sustainability of irrigated agriculture on water limited ecosystems. Consequently, a thorough understanding of this phenomenon is necessary to avoid future problems. With the objective of identifying irrigated land expansion dynamics and the primary drivers, two representative oasis regions in Southern Tunisia, Mareth and Fatnassa, were selected. Changes in irrigated lands in both regions between 1985 and 2011 were analyzed, and the land uses from which expansion occurred were identified using Landsat images from different years (1985, 1996 and 2011). The results indicate that the surface occupied by irrigation agriculture has doubled in Mareth, while in Fatnassa, it has increased fourfold. During that period, there was a simultaneous increase in total population, as consequence of human migration that came along with an increase in income. Thus, we could identify human migration and economic development as potential drivers of irrigated agriculture expansion, though further research is warranted to ascertain a quantification that would assist in obtaining the sustainability of these regions.

  10. Ultrasound attenuation dependence on air compression or expansion processes

    NARCIS (Netherlands)

    Jakevicius, L.; Demcenko, A.; Mardosaite, R.

    2010-01-01

    In this work variation of ultrasonic attenuation coefficient is analyzed in terms of air compression or expansion processes. In closed spaces changing air volume, the ultrasound attenuation coefficient depends on thermodynamic processes which occur during the air volume change. Two limiting cases

  11. The Government Response to the Private Sector Expansion in Poland

    NARCIS (Netherlands)

    Antonowicz, Dominik; Kwiek, Marek; Westerheijden, Donald F.; Boer, Harry; File, Jon; Huisman, Jeroen; Seeber, Marco; Vukasovic, Martina; Westerheijden, Don F.

    2017-01-01

    One of the trademarks of transformation of Polish higher education is its tumultuous and inconsistent path of development driven by the rapid growth of private sector higher education. Such an expansion has been often described as a ‘sudden, shocking and unplanned’ phenomenon which revolutionized

  12. Range expansion of the hadeda ibis Bostrychia hagedash in ...

    African Journals Online (AJOL)

    The reasons for this expansion were investigated. Important factors include reduction in human persecution following the introduction of legislation in the period 1934 to 1941 and an increase of alien trees in formerly treeless areas. The increases in artificial impoundments and areas under irrigation are thought to have ...

  13. Population growth, urban expansion, and private forestry in western Oregon.

    Science.gov (United States)

    Jeffrey D. Kline; David L. Azuma; Ralph J. Alig

    2004-01-01

    Private forestlands in the United States face increasing pressures from growing populations, resulting in greater numbers of people living in closer proximity to forests. What often is called the "wildland/urban interface" is characterized by expansion of residential and other developed land uses onto forested landscapes in a manner that threatens forestlands...

  14. [Landscape ecological security pattern during urban expansion of Nanchong City].

    Science.gov (United States)

    Li, Sui; Shi, Tie-mao; Fu, Shi-lei; Zhou, Le; Liu, Miao; Wang, Wei

    2011-03-01

    Based on the theory of landscape ecological security pattern and the RS and GIS techniques, this paper analyzed the distribution of ecological security grades in Nanchong City, taking six elements including terrain condition, flood hazard, soil erosion, vegetation cover, geological disaster, and biological protection as the ecological constraints (or determinants) of urban expansion. According to the minimum cumulative resistance model, the ecological corridors and ecological nodes were built to strengthen the space contact of ecological network, and, on the basis of the protection of ecological safety, the reasonable trend of urban expansion and the optimization of space layout were investigated. The results showed that the ecological security of Nanchong City was quite good, with the regions of low ecological security mainly distributed in the west suburban mountains and the downstream region of Jialing River in the south of the City. Ecological elements were the most important constraints for the future expansion of urban space. There were more spaces for the urban expansion in the southern and northern parts of Nanchong City. To develop satellite towns would be the best selection to guarantee the ecological security of the city.

  15. Thermal expansion behaviour of barium and strontium zirconium ...

    Indian Academy of Sciences (India)

    Unknown

    Thermal expansion behaviour of barium and strontium zirconium phosphates. P SRIKARI TANTRI, K GEETHA†, A M UMARJI† and SHEELA K RAMASESHA*. Materials Science Division, National Aerospace Laboratories, Bangalore 560 017, India. †Materials Research Centre, Indian Institute of Science, Bangalore 560 ...

  16. Mangrove expansion and population structure at a planted site, East ...

    African Journals Online (AJOL)

    The expansion of mangroves was measured using past aerial photographs and Esri ArcGIS Desktop 10 software. In addition, field surveys were completed in 2011 to determine the population structure of the present mangrove forest and relate this to environmental conditions. The study showed that mangrove area cover ...

  17. Bilateral Re-Expansion Pulmonary Oedema– When the Cure Is ...

    African Journals Online (AJOL)

    Background: Re-expansion pulmonary oedema is a potentially fatal consequence of rapid reexpansion of a lung, which has been collapsed due to a pleural effusion or a pneumothorax. Case Report: We report a very unusual case in which the patient initially developed ipsilateral followed by contralateral pulmonary ...

  18. Educational Expansion and Inequality in Taiwan and the Czech Republic

    Science.gov (United States)

    Smith, Michael; Tsai, Shu-Ling; Mateju, Petr; Huang, Min-Hsiung

    2016-01-01

    This article presents a comparative analysis of educational inequality by family background and gender in Taiwan and the Czech Republic, which have both experienced substantial educational expansion in the last half-century under different educational systems. We highlight the specific institutional histories of both countries and examine the role…

  19. [Unilateral surgically assisted rapid maxillary expansion using a transpalatal distractor].

    NARCIS (Netherlands)

    Roelofs, J.; Breuning, K.H.; Spijker, A. van 't; Borstlap, W.A.; Berge, S.J.; Kuijpers-Jagtman, A.M.

    2010-01-01

    A 46-year-old woman was referred for orthodontic surgery consultation because ofa retrognathic maxilla, unilateral cross bite and functional, aesthetic and speech problems. The maxilla was widened unilaterally by unilateral surgically assisted rapid maxillary expansion with a bone-borne transpalatal

  20. The Drivers of Brazil's Expansion into Africa: A Critical Assessment ...

    African Journals Online (AJOL)

    The rise of neoliberalism and global power reorganization through globalization and capital expansion allows emerging economies like Brazil to redefine their role in an international arena and challenge the traditional power dynamics between North and South. In this sense, and by giving a 'human face' to the neoliberal ...

  1. Population growth and settlement expansion in the fringes of Addis ...

    African Journals Online (AJOL)

    This study focuses on estimating the rate of urban settlement expansion in the fringes of Addis Ababa, and on examining the causes for this and the impacts it has on the livelihoods of the farming households living there. For this purpose, aerial photographs covering the study area, GIS tools and GPS were used; ...

  2. Growth And Export Expansion In Mauritius - A Time Series Analysis ...

    African Journals Online (AJOL)

    This paper analyses the empirical relationship between economic growth and export expansion in Mauritius as observed through time series data. Using Granger Causality tests, the short-run analysis results revealed that there is significant reciprocal causality between real export earnings (total, textiles and manufacturing) ...

  3. Heterogeneous LTE-Advanced Network Expansion for 1000x Capacity

    DEFF Research Database (Denmark)

    Hu, Liang; Sanchez, Maria Laura Luque; Maternia, Michal

    2013-01-01

    this paper studies LTE (Long-Term Evolution)-Advanced heterogeneous network expansion in a dense urban environment for a 1000 times capacity increase and a 10 times increase in minimum user data rate requirements. The radio network capacity enhancement via outdoor and indoor small cell densificat...

  4. Lattice expansion of carbon-stabilized expanded austenite

    DEFF Research Database (Denmark)

    Hummelshøj, Thomas Strabo; Christiansen, Thomas; Somers, Marcel A. J.

    2010-01-01

    The lattice parameter of expanded austenite was determined as a function of the content of interstitially dissolved carbon in homogeneous, carburized thin stainless steel foils. For the first time this expansion of the face-centered cubic lattice is determined on unstrained austenite. It is found...

  5. Thermal Expansion and Aging Effects in Neuromorphic Signal Processor

    NARCIS (Netherlands)

    Zjajo, A.; van Leuken, T.G.R.M.

    2016-01-01

    In this paper, we propose an efficient methodology based on a real-time estimator and predictor-corrector scheme for accurate thermal expansion profile and aging evaluation of a neuromorphic signal processor circuit components. As the experimental results indicate, for comparable mesh size, the

  6. Ultra low and negative expansion glass–ceramic materials ...

    Indian Academy of Sciences (India)

    Ultra low and negative expansion glass–ceramic materials have been obtained from pyrophyllite and blast furnace slag. The batch composition was modified with the addition of lithium carbonate, hydrated alumina, boric acid and nucleating agent (titania). The batch was melted at 1400°C followed by casting in the form of ...

  7. Surgically Assisted Rapid Maxillary Expansion: surgical and orthodontic aspects

    NARCIS (Netherlands)

    M.J. Koudstaal (Maarten)

    2008-01-01

    textabstractThe scope of this thesis is to shed more light, from a number of perspectives, on surgically assisted rapid maxillary expansion (SARME). The primary questions this thesis set out to answer were; ‘is there a difference in stability between bone-borne and tooth-borne distraction?’ and ‘can

  8. Antimicrobial Treatment to Impair Expansion of Abdominal Aortic Aneurysm (AAA)

    DEFF Research Database (Denmark)

    Bergqvist, David; Lindeman, Johannes H N; Lindholt, Jes Sanddal

    2013-01-01

    Antimicrobial treatment to attenuate expansion of abdominal aortic aneurysm has been suggested, especially with the focus on Chlamydophila. In this systematic literature review only four randomized trials were identified. In two small studies there is an indication of an effect of roxithromycin. ...

  9. Edgeworth expansions and normalizing transforms for inequality measures

    NARCIS (Netherlands)

    Schluter, C.; van Garderen, K.J.

    2009-01-01

    Finite sample distributions of studentized inequality measures differ substantially from their asymptotic normal distribution in terms of location and skewness. We study these aspects formally by deriving the second-order expansion of the first and third cumulant of the studentized inequality

  10. Strike up Student Interest through Song: Technology and Westward Expansion

    Science.gov (United States)

    Steele, Meg

    2014-01-01

    Sheet music, song lyrics, and audio recordings may not be the first primary sources that come to mind when considering ways to teach about changes brought about by technology during westward expansion, but these sources engage students in thought provoking ways. In this article the author presents a 1917 photograph of Mountain Chief, of the Piegan…

  11. From A to Z: Asymptotic expansions by van Zwet

    NARCIS (Netherlands)

    Albers, Willem/Wim; de Gunst, Mathisca; Klaasen, Chris; van der Vaart, Aad

    2001-01-01

    Refinements of first order asymptotic results axe reviewed, with a number of Ph.D. projects supervised by van Zwet serving as stepping stones. Berry-Esseen bounds and Edgeworth expansions are discussed for R-, L- and [/-statistics. After these special classes, the question about a general second

  12. From A to Z: asymptotic expansions by van Zwet

    NARCIS (Netherlands)

    Albers, Willem/Wim; de Gunst, M.C.M.; Klaassen, C.A.J.; van der Vaart, A.W.

    2001-01-01

    Refinements of first order asymptotic results are reviewed, with a number of Ph.D. projects supervised by van Zwet serving as stepping stones. Berry-Esseen bounds and Edgeworth expansions are discussed for R-, L- and U-statistics. After these special classes, the question about a general second

  13. Higher Education Expansion in China and the "Ant Tribe" Problem

    Science.gov (United States)

    He, Yu; Mai, Yinhua

    2015-01-01

    College Enrolment Expansion policies have been implemented in China since 1999. Unfortunately, numbers of qualified teachers and the amount of educational funds input have not caught up with the pace of student intake. Even the curricula taught in colleges are outdated and work practice programmes are inefficient. As a result, new college…

  14. Evaluation of Speedup and Expansion in Terabit Switch Fabrics

    DEFF Research Database (Denmark)

    Ruepp, Sarah Renée; Rytlig, Andreas; Berger, Michael Stübert

    2011-01-01

    This paper evaluates speedup and expansion in a multi-stage Terabit switch fabric. Single-stage switch fabrics, e.g. crossbar switches, are difficult to scale up to a Terabit system. Hence, a multi-stage switch fabric, where traffic can be distributed on different chips, offers a promising...

  15. Task-Based Language Teaching and Expansive Learning Theory

    Science.gov (United States)

    Robertson, Margaret

    2014-01-01

    Task-Based Language Teaching (TBLT) has become increasingly recognized as an effective pedagogy, but its location in generalized sociocultural theories of learning has led to misunderstandings and criticism. The purpose of this article is to explain the congruence between TBLT and Expansive Learning Theory and the benefits of doing so. The merit…

  16. Medicaid in Ohio: The Politics of Expansion, Reauthorization, and Reform.

    Science.gov (United States)

    Skinner, Daniel

    2015-12-01

    When, in 2012, the US Supreme Court held that Medicaid expansion sanctioned by the Affordable Care Act (ACA) was essentially optional for states, it ushered in a newly contentious state politics. States led by Republican governors and legislatures opposed to the ACA had to decide whether to accept extensive federal funding to expand Medicaid for citizens in their states who were earning up to 138 percent of the federal poverty level. This Report from the States focuses on Ohio, whose Republican governor successfully navigated the rancorous politics of Medicaid to expand the state's program in 2014. Working at odds with his own party and gaining praise from traditional political opponents for his leadership on the issue, John Kasich circumvented the state legislature, turning to the Controlling Board to bring about initial expansion. In the wake of Kasich's landslide reelection in 2014, the politics of expansion and reauthorization have given way to a pervasive discourse of "reform." In this next phase Kasich has endorsed policy positions (e.g., cost sharing, a focus on "personal responsibility") that reunite him with his party's more traditional view of Medicaid while continuing to emphasize the importance of expansion. Copyright © 2016 by Duke University Press.

  17. Alloy design as an inverse problem of cluster expansion models

    DEFF Research Database (Denmark)

    Larsen, Peter Mahler; Kalidindi, Arvind R.; Schmidt, Søren

    2017-01-01

    Central to a lattice model of an alloy system is the description of the energy of a given atomic configuration, which can be conveniently developed through a cluster expansion. Given a specific cluster expansion, the ground state of the lattice model at 0 K can be solved by finding the configurat......Central to a lattice model of an alloy system is the description of the energy of a given atomic configuration, which can be conveniently developed through a cluster expansion. Given a specific cluster expansion, the ground state of the lattice model at 0 K can be solved by finding...... the configuration of solutes that minimizes the energy of the system. In this paper, we develop a method for solving the inverse lattice problem, where, given a broad class of potential, we find the ground states for all possible values of the effective cluster interaction energies. To do so, we formulate...... the inverse problem in terms of energetically distinct configurations, using a constraint satisfaction model to identify constructible configurations, and show that a convex hull can be used to identify ground states. To demonstrate the approach, we solve for all ground states for a binary alloy in a 2D...

  18. Perception Expansion Training: An Approach to Conflict Reduction.

    Science.gov (United States)

    Huseman, Richard C.

    Interpersonal conflict in organizations is due to differences in perception of organizational sub-group systems operations. Such conflict can be reduced through implementation of "PET," perception expansion training. PET procedures will determine the dimensions of conflict situations and bring into play interacting group therapy which expands the…

  19. HOXD13 polyalanine tract expansion in classical synpolydactyly type Vordingborg

    DEFF Research Database (Denmark)

    Kjær, Klaus Wilbrandt; Hedeboe, Jess; Bugge, Merete

    2002-01-01

    In 1927, Oluf Thomsen, in a classic paper, described a seven-generation family with autosomal dominant axial synpolydactyly (SPD)--the Vordingborgtyp of axis duplication and dysostosis. Expansion of a polyalanine tract in the HOXD13 gene is known to cause synpolydactyly. We have rediscovered part...

  20. Wasted Citizenship? Reclaimers and the Privatised Expansion of ...

    African Journals Online (AJOL)

    Less attention has been paid, however, to the privatised expansion of the public sphere. This article explores such a process in Metsimaholo, South Africa, where the municipality sought to bring landfill recycling into the realm of public policy through a public-private partnership. As informal reclaimers had salvaged ...

  1. Quality of potential harmonics expansion method for dilute Bose ...

    Indian Academy of Sciences (India)

    Abstract. We present and examine an approximate but ab initio many-body approach, viz., potential harmonics expansion method (PHEM), which includes two-body correla- tions for dilute Bose–Einstein condensates. .... in coupled angular momentum representation. Now Y[K](Ω) must be totally sym- metric under any pair ...

  2. Autochthonous Outbreak and Expansion of Canine Visceral Leishmaniasis, Uruguay

    Science.gov (United States)

    Satragno, Dinora; Faral-Tello, Paula; Canneva, Bruno; Verger, Lorenzo; Lozano, Alejandra; Vitale, Edgardo; Greif, Gonzalo; Soto, Carlos

    2017-01-01

    We report an outbreak of canine visceral leishmaniasis in Uruguay. Blood specimens from 11/45 dogs tested positive for Leishmania spp. Specimens of Lutzomyia longipalpis sand flies were captured; typing revealed Leishmania infantum. Our findings document an expansion of visceral leishmaniasis to southern South America and risk for vectorborne transmission to humans. PMID:28221113

  3. Shrub expansion in tundra ecosystems: dynamics, impacts and research priorities

    NARCIS (Netherlands)

    Myers-Smith, I.H.; Forbes, B.C.; Wilmking, M.; Hallinger, M.; Lantz, T.; Blok, D.; Sass, U.G.W.

    2011-01-01

    Part of Focus on Dynamics of Arctic and Sub-Arctic Vegetation Recent research using repeat photography, long-term ecological monitoring and dendrochronology has documented shrub expansion in arctic, high-latitude and alpine tundra ecosystems. Here, we (1) synthesize these findings, (2) present a

  4. Laser ablation plume expansion into an ambient gas

    DEFF Research Database (Denmark)

    Amoruso, S.; Schou, Jørgen; Lunney, J.G.

    2009-01-01

    The use of an ambient gas is a well-established method employed in pulsed laser deposition (PLD) with nanosecond pulses and has been extensively studied in this context. Most of the existing treatments of the plume expansion are tackled by using complex numerical modeling involving specific target...

  5. 2011 USGS Topographic LiDAR: Suwannee River Expansion

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — USGS Task Order No. G10PD00236 USGS Contract No. G10PC00093 The Light Detection and Ranging (LiDAR) dataset is a survey of the Suwannee River Expansion in...

  6. Biophysical constraints on leaf expansion in a tall conifer.

    Science.gov (United States)

    Fredrick C. Meinzer; Barbara J. Bond; Jennifer A. Karanian

    2008-01-01

    The physiological mechanisms responsible for reduced extension growth as trees increase in height remain elusive. We evaluated biophysical constraints on leaf expansion in old-growth Douglas-fir (Psuedotsuga menziesii (Mirb.) Franco) trees. Needle elongation rates, plastic and elastic extensibility, bulk leaf water, (L...

  7. The thermospheric effects of a rapid polar cap expansion

    Directory of Open Access Journals (Sweden)

    D. W. Idenden

    Full Text Available In a previous publication we used results from a coupled thermosphere-ionosphere-plasmasphere model to illustrate a new mechanism for the formation of a large-scale patch of ionisation arising from a rapid polar cap expansion. Here we describe the thermospheric response to that polar cap expansion, and to the ionospheric structure produced. The response is dominated by the energy and momentum input at the dayside throat during the expansion phase itself. These inputs give rise to a large-scale travelling atmospheric disturbance (TAD that propagates both antisunward across the polar cap and equatorward at speeds much greater than both the ion drifts and the neutral winds. We concentrate only on the initially poleward travelling disturbance. The disturbance is manifested in the neutral temperature and wind fields, the height of the pressure level surfaces and in the neutral density at fixed heights. The thermospheric effects caused by the ionospheric structure produced during the expansion are hard to discern due to the dominating effects of the TAD.

    Key words. Ionosphere (ionosphere · atmosphere interaction; modeling and forecasting; plasma convection.

  8. The thermospheric effects of a rapid polar cap expansion

    Directory of Open Access Journals (Sweden)

    D. W. Idenden

    1998-10-01

    Full Text Available In a previous publication we used results from a coupled thermosphere-ionosphere-plasmasphere model to illustrate a new mechanism for the formation of a large-scale patch of ionisation arising from a rapid polar cap expansion. Here we describe the thermospheric response to that polar cap expansion, and to the ionospheric structure produced. The response is dominated by the energy and momentum input at the dayside throat during the expansion phase itself. These inputs give rise to a large-scale travelling atmospheric disturbance (TAD that propagates both antisunward across the polar cap and equatorward at speeds much greater than both the ion drifts and the neutral winds. We concentrate only on the initially poleward travelling disturbance. The disturbance is manifested in the neutral temperature and wind fields, the height of the pressure level surfaces and in the neutral density at fixed heights. The thermospheric effects caused by the ionospheric structure produced during the expansion are hard to discern due to the dominating effects of the TAD.Key words. Ionosphere (ionosphere · atmosphere interaction; modeling and forecasting; plasma convection.

  9. Prediction of Swelling Behavior of Addis Ababa Expansive Soil ...

    African Journals Online (AJOL)

    In this study a simple hyperbolic mathematical model is used to predict the swelling behavior of an expansive soil from Addis Ababa. The main parameters that are needed to run the model are the applied pressure and initial dry density. The other parameters of the model including the initial slope of the swell-time curve, the ...

  10. expansion method and travelling wave solutions for the perturbed ...

    Indian Academy of Sciences (India)

    Abstract. In this paper, we construct the travelling wave solutions to the perturbed nonlinear. Schrödinger's equation (NLSE) with Kerr law non-linearity by the extended (G /G)-expansion method. Based on this method, we obtain abundant exact travelling wave solutions of NLSE with. Kerr law nonlinearity with arbitrary ...

  11. The extended (G/G)-expansion method and travelling wave ...

    Indian Academy of Sciences (India)

    In this paper, we construct the travelling wave solutions to the perturbed nonlinear Schrödinger's equation (NLSE) with Kerr law non-linearity by the extended (′/)-expansion method. Based on this method, we obtain abundant exact travelling wave solutions of NLSE with Kerr law nonlinearity with arbitrary parameters.

  12. Development of Low Thermal Expansion Tungsten UO 2 Cermet Fuel

    Energy Technology Data Exchange (ETDEWEB)

    Marlowe, M O; Kaznoff, A I

    1970-03-31

    An attempt was made to develop a tungsten-uranium dioxide cermet of high fue 1 loading with thermal expansion approaching that of tungsten and with good dimensional stability on thermal cycling. These goals were sought through the use of tungsten-coated uranium dioxide particles with sufficient locally available void volume to accommodate the difference in thermal expansion between the uranium dioxide and the tungsten matrix and through limitation of plastic deformation in the particles during fabrication to avoid mechanical keying of the particles and the matrix. The particles were vibratorily compacted prior to hot pressing. The thermal expansion of the cermets was determined and they were thermal cycle tested. The thermal expansion of the cermets was considerably closer to that of tungsten than was observed with previously reported specimens of similar composition. However, the thermal cycling of the cermets resulted in intolerable growth. This growth could be accounted for by the agglomeration of gases trapped in the uranium dioxide particles during deposition of the tungsten coating.

  13. Port expansion of Puerto de Lirquén, Chile

    NARCIS (Netherlands)

    De Fockert, A.; Graafland, T.; Paap, E.; Van der Plas, T.; Roubos, A.

    2005-01-01

    The container yard of the port of Lirquen will reach its capacity in a few years and the container terminal has no landward expansion possibilities to meet the future demand of container throughput. The bulk terminal has a lack of berths, due to increased throughput and insufficient depth, but does

  14. Engel Series and Cohen-Egyptian Fraction Expansions

    Directory of Open Access Journals (Sweden)

    Vichian Laohakosol

    2009-01-01

    Full Text Available Two kinds of series representations, referred to as the Engel series and the Cohen-Egyptian fraction expansions, of elements in two different fields, namely, the real number and the discrete-valued non-archimedean fields are constructed. Both representations are shown to be identical in all cases except the case of real rational numbers.

  15. 76 FR 56091 - Expansion of 911 Access; Telecommunications Loan Program

    Science.gov (United States)

    2011-09-12

    ... Service 7 CFR Part 1735 RIN 0572-AC24 Expansion of 911 Access; Telecommunications Loan Program AGENCY... access and integrated emergency communications systems in rural areas for the Telecommunications Loan... Villano, Assistant Administrator, Telecommunications Program, USDA--Rural Utilities Service, 1400...

  16. Dynamics of plasma expansion in the pulsed laser material interaction

    Indian Academy of Sciences (India)

    It is seen from present computations that the forward directed nature of the laser evaporation process results from the anisotropic expansion velocities associated with different species. These velocities are mainly controlled by the initial dimension of the expanding plasma. An attempt was undertaken to estimate the length of ...

  17. A Model for the Expansion of the Universe

    Directory of Open Access Journals (Sweden)

    Silva N. P.

    2014-04-01

    Full Text Available One introduces an ansatz for the expansion factor a ( t = e ( H ( t t or our Universe in the spirit of the FLRW model; is a constant to be determined. Considering that the ingredients acting on the Universe expansion ( t > 4 10 12 s 1 : 3 10 are mainly matter (baryons plus dark matter and dark energy, one uses the current mea- sured values of Hubble constant H 0 , the Universe current age T 0 , matter density param- eter Ω m ( T 0 and dark energy parameter Ω ( T 0 together with the Friedmann equations to find = 0 : 5804 and that our Universe may have had a negative expansion accelera- tion up to the age T ⋆ = 3 : 214 G y r ( matter era and positive after that ( dark energy era , leading to an eternal expansion. An interaction between matter and dark energy is found to exist. The deceleration q ( t has been found to be q ( T ⋆ = 0 and q ( T 0 = -0.570.

  18. Flexible Transport Network Expansion via Open WDM Interfaces

    DEFF Research Database (Denmark)

    Fagertun, Anna Manolova; Skjoldstrup, Bjarke

    2013-01-01

    This paper presents a successful test-bed implementation of a multi-vendor transport network interconnection via open WDM interfaces. The concept of applying Alien Wavelengths (AWs) for network expansion was successfully illustrated via deployment of multi-domain/multi-vendor end-to-end OTN...

  19. expansion method for the Burgers, Burgers–Huxley and modified ...

    Indian Academy of Sciences (India)

    mathematical physics. Keywords. (G /G)-expansion method; Burgers equation; Burgers–Huxley equation; modified. Burgers–KdV equation; travelling wave solutions. PACS Nos 02.30.Jr; 02.70.Wz; 05.45.Yv; 94.05.Fg. 1. Introduction. Most of the phenomena in real world can be described using nonlinear equations. In recent.

  20. Modeling urban expansion by using variable weights logistic cellular automata

    NARCIS (Netherlands)

    Shu, Bangrong; Bakker, Martha M.; Zhang, Honghui; Li, Yongle; Qin, Wei; Carsjens, Gerrit J.

    2017-01-01

    Simulation models based on cellular automata (CA) are widely used for understanding and simulating complex urban expansion process. Among these models, logistic CA (LCA) is commonly adopted. However, the performance of LCA models is often limited because the fixed coefficients obtained from binary

  1. Oil palm expansion without enclosure: smallholders and environmental narratives

    NARCIS (Netherlands)

    Castellanos Navarrete, A.; Jansen, K.

    2015-01-01

    Recent debates on land grabbing and biofuels tend to link oil palm expansion to rural dispossession, environmental degradation and rural resistance. In this paper, we examine to what extent ‘enclosure’, a central concept in two critiques – ‘environmentalism of the poor’ and ‘green grabbing’ – is

  2. Optimized t-expansion method for the Rabi Hamiltonian

    Energy Technology Data Exchange (ETDEWEB)

    Travenec, Igor, E-mail: fyzitrav@savba.sk [Institute of Physics, Slovak Academy of Sciences, Dubravska cesta 9, 845 11 Bratislava (Slovakia); Samaj, Ladislav [Institute of Physics, Slovak Academy of Sciences, Dubravska cesta 9, 845 11 Bratislava (Slovakia)

    2011-10-31

    A polemic arose recently about the applicability of the t-expansion method to the calculation of the ground state energy E{sub 0} of the Rabi model. For specific choices of the trial function and very large number of involved connected moments, the t-expansion results are rather poor and exhibit considerable oscillations. In this Letter, we formulate the t-expansion method for trial functions containing two free parameters which capture two exactly solvable limits of the Rabi Hamiltonian. At each order of the t-series, E{sub 0} is assumed to be stationary with respect to the free parameters. A high accuracy of E{sub 0} estimates is achieved for small numbers (5 or 6) of involved connected moments, the relative error being smaller than 10{sup -4} (0.01%) within the whole parameter space of the Rabi Hamiltonian. A special symmetrization of the trial function enables us to calculate also the first excited energy E{sub 1}, with the relative error smaller than 10{sup -2} (1%). -- Highlights: → We study the ground state energy of the Rabi Hamiltonian. → We use the t-expansion method with an optimized trial function. → High accuracy of estimates is achieved, the relative error being smaller than 0.01%. → The calculation of the first excited state energy is made. The method has a general applicability.

  3. The future of Arctic benthos: Expansion, invasion, and biodiversity

    Science.gov (United States)

    Renaud, Paul E.; Sejr, Mikael K.; Bluhm, Bodil A.; Sirenko, Boris; Ellingsen, Ingrid H.

    2015-12-01

    One of the logical predictions for a future Arctic characterized by warmer waters and reduced sea-ice is that new taxa will expand or invade Arctic seafloor habitats. Specific predictions regarding where this will occur and which taxa are most likely to become established or excluded are lacking, however. We synthesize recent studies and conduct new analyses in the context of climate forecasts and a paleontological perspective to make concrete predictions as to relevant mechanisms, regions, and functional traits contributing to future biodiversity changes. Historically, a warmer Arctic is more readily invaded or transited by boreal taxa than it is during cold periods. Oceanography of an ice-free Arctic Ocean, combined with life-history traits of invading taxa and availability of suitable habitat, determine expansion success. It is difficult to generalize as to which taxonomic groups or locations are likely to experience expansion, however, since species-specific, and perhaps population-specific autecologies, will determine success or failure. Several examples of expansion into the Arctic have been noted, and along with the results from the relatively few Arctic biological time-series suggest inflow shelves (Barents and Chukchi Seas), as well as West Greenland and the western Kara Sea, are most likely locations for expansion. Apparent temperature thresholds were identified for characteristic Arctic and boreal benthic fauna suggesting strong potential for range constrictions of Arctic, and expansions of boreal, fauna in the near future. Increasing human activities in the region could speed introductions of boreal fauna and reduce the value of a planktonic dispersal stage. Finally, shelf regions are likely to experience a greater impact, and also one with greater potential consequences, than the deep Arctic basin. Future research strategies should focus on monitoring as well as compiling basic physiological and life-history information of Arctic and boreal taxa, and

  4. Global Monte Carlo Simulation with High Order Polynomial Expansions

    Energy Technology Data Exchange (ETDEWEB)

    William R. Martin; James Paul Holloway; Kaushik Banerjee; Jesse Cheatham; Jeremy Conlin

    2007-12-13

    The functional expansion technique (FET) was recently developed for Monte Carlo simulation. The basic idea of the FET is to expand a Monte Carlo tally in terms of a high order expansion, the coefficients of which can be estimated via the usual random walk process in a conventional Monte Carlo code. If the expansion basis is chosen carefully, the lowest order coefficient is simply the conventional histogram tally, corresponding to a flat mode. This research project studied the applicability of using the FET to estimate the fission source, from which fission sites can be sampled for the next generation. The idea is that individual fission sites contribute to expansion modes that may span the geometry being considered, possibly increasing the communication across a loosely coupled system and thereby improving convergence over the conventional fission bank approach used in most production Monte Carlo codes. The project examined a number of basis functions, including global Legendre polynomials as well as “local” piecewise polynomials such as finite element hat functions and higher order versions. The global FET showed an improvement in convergence over the conventional fission bank approach. The local FET methods showed some advantages versus global polynomials in handling geometries with discontinuous material properties. The conventional finite element hat functions had the disadvantage that the expansion coefficients could not be estimated directly but had to be obtained by solving a linear system whose matrix elements were estimated. An alternative fission matrix-based response matrix algorithm was formulated. Studies were made of two alternative applications of the FET, one based on the kernel density estimator and one based on Arnoldi’s method of minimized iterations. Preliminary results for both methods indicate improvements in fission source convergence. These developments indicate that the FET has promise for speeding up Monte Carlo fission source

  5. Dermal filler injection: a novel approach for limiting infarct expansion.

    Science.gov (United States)

    Ryan, Liam P; Matsuzaki, Kanji; Noma, Mio; Jackson, Benjamin M; Eperjesi, Thomas J; Plappert, Theodore J; St John-Sutton, Martin G; Gorman, Joseph H; Gorman, Robert C

    2009-01-01

    Early infarct expansion after coronary occlusion compromises contractile function in perfused myocardial regions and promotes adverse long-term left ventricular (LV) remodeling. We hypothesized that injection of a tissue-expanding dermal filler material into a myocardial infarction (MI) would attenuate infarct expansion and limit LV remodeling. Fifteen sheep were subjected to an anteroapical MI involving approximately 20% of the LV followed by the injection of 1.3 mL of a calcium hydroxyapatite-based dermal filler into the infarct. Real-time three-dimensional echocardiography was performed at baseline, 30 minutes after MI, and 15 minutes after injection to assess infarct expansion. Sixteen additional sheep were subjected to the same infarction and followed echocardiographically and hemodynamically for 4 weeks after MI to assess chronic remodeling. Eight animals had injection with dermal filler as described above immediately after MI, and 8 animals were injected with an equal amount of saline solution. All animals exhibited infarct expansion soon after coronary occlusion. The regional ejection fraction of the apex became negative after infarction, consistent with systolic dyskinesia. Injection of the dermal filler converted the apical wall motion from dyskinetic to akinetic and resulted immediately in significant decreases in global, regional, and segmental LV volumes. Chronically, relative to saline control, dermal filler injection significantly reduced LV end-systolic volume (62.2 +/- 3.6 mL versus 44.5 +/- 3.9 mL; p < 0.05) and improved global ejection fraction (0.295 +/- 0.016 versus 0.373 +/- 0.017; p < 0.05) at 4 weeks after infarction. Injection of an acellular dermal filler into an MI immediately after coronary occlusion reduces early infarct expansion and limits chronic LV remodeling.

  6. Hygroscopic expansion kinetics of dental resin-composites.

    Science.gov (United States)

    Alrahlah, A; Silikas, N; Watts, D C

    2014-02-01

    To evaluate the extent and rate of hygroscopic expansion of resin composites at 37°C. Eight resin composites were examined: 1 micro-hybrid (Bright Light(®)), 5 nano-hybrids (Experimental Vertise™; Nanoceram-Bright(®); Tetric EvoCeram(®); Grandio(®) SO; Ceram X™ duo) and 2 flowables (X-tra base; Venus(®) Diamond Flow). Five disks (15 mm×2 mm) of each material were prepared. The mean change in specimen diameter was recorded by a custom-built non-contact laser micrometer. Specimens were initially measured dry and then at fixed time intervals, over 150 days, after storage in distilled water at 37±1°C. Data were re-expressed in volumetric terms and analysed by repeated measures ANOVA, one-way ANOVA and Tukey's post hoc test (α=0.05). The volumetric hygroscopic expansion ranged from 0.58 to 2.26 and can be considered in three bands. First, Experimental Vertise had the highest expansion (p<0.001). Venus Diamond Flow, Tetric EvoCeram and Ceram X duo were the second band. The third band, with still lower expansion, consisted of Bright light, Grandio So, Nanoceram-Bright and X-tra base, with no significant difference between them. For the size (2mm thickness) and shape of specimen measured, equilibrium was attained in all cases by 60 days. Within this set of resin-composites the equilibrium expansion varied by almost 400% of the lowest material. Copyright © 2013 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

  7. Understanding the expansion of energy crops beyond the global biofuel boom : evidence from oil palm expansion in Colombia

    NARCIS (Netherlands)

    Marin-Burgos, Victoria; Clancy, Joy S.

    2017-01-01

    Background: The global palm oil market experienced a remarkable boom since the year 2000. Since palm oil can be used for biodiesel production, the global expansion of oil palm cultivation has been associated with the global biofuel boom. Biofuel policies—especially those adopted in the European

  8. Tube Expansion Under Various Down-Hole End Conditions

    Directory of Open Access Journals (Sweden)

    FJ Sanchez

    2013-06-01

    Full Text Available Fossil hydrocarbons are indispensables commodities that motorize the global economy, and oil and gas are two of those conventional fuels that have been extracted and processed for over a century. During last decade, operators face challenges discovering and developing reservoirs commonly found up to several kilometers underground, for which advanced technologies are developed through different research programs. In order to optimize the current processes to drill and construct oil/gas wells, a large number of mechanical technologies discovered centuries ago by diverse sectors are implemented by well engineers. In petroleum industry, the ancient tube forming manufacturing process founds an application once well engineers intend to produce from reservoirs that cannot be reached unless previous and shallower troublesome formations are isolated. Solid expandable tubular is, for instance, one of those technologies developed to mitigate drilling problems and optimize the well delivery process. It consists of in-situ expansion of a steel-based tube that is attained by pushing/pulling a solid mandrel, which permanently enlarge its diameters. This non-linear expansion process is strongly affected by the material properties of the tubular, its geometry, and the pipe/mandrel contact surface. The anticipated force required to deform long sections of the pipe in an uncontrollable expansion environment, might jeopardize mechanical properties of the pipe and the well structural integrity. Scientific-based solutions, that depend on sound theoretical formulation and are validated through experiments, will help to understand possible tubular failure mechanisms during its operational life. This work is aimed to study the effect of different loading/boundary conditions on mechanical/physical properties of the pipe after expansion. First, full-scale experiments were conducted to evaluate the geometrical and behavioral changes. Second, simulation of deformation

  9. Expansion of Bose-Hubbard Mott insulators in optical lattices

    Energy Technology Data Exchange (ETDEWEB)

    Jreissaty, Mark; Carrasquilla, Juan; Rigol, Marcos [Department of Physics, Georgetown University, Washington DC 20057 (United States); Wolf, F. Alexander [Department of Physics, Georgetown University, Washington DC 20057 (United States); Theoretical Physics III, Center for Electronic Correlations and Magnetism, Institute of Physics, Augsburg University, D-86135 Augsburg (Germany)

    2011-10-15

    We study the expansion of bosonic Mott insulators in the presence of an optical lattice after switching off a confining potential. We use the Gutzwiller mean-field approximation and consider two different setups. In the first one, the expansion is restricted to one direction. We show that this leads to the emergence of two condensates with well-defined momenta, and argue that such a construct can be used to create atom lasers in optical lattices. In the second setup, we study Mott insulators that are allowed to expand in all directions in the lattice. In this case, a simple condensate is seen to develop within the mean-field approximation. However, its constituent bosons are found to populate many nonzero momentum modes. An analytic understanding of both phenomena in terms of the exact dispersion relation in the hard-core limit is presented.

  10. Modification of the technique of osteotomy for surgical maxillary expansion

    Directory of Open Access Journals (Sweden)

    João Luis Carlini

    2015-10-01

    Full Text Available Surgically assisted maxillary expansion is a technique used to correct transverse maxillary deficiency, which is a dentofacial anomaly related to the decrease of the upper arch over the lower arch. It is applied to patients in their late teens and adults due to skeletal maturity, causing obliteration of the intermaxillary suture, which requires orthodontic procedure, associated with surgery. The purpose of this study is to report the clinical case of a patient admitted for surgical maxillary expansion through the modified technique and point out the possible advantages, such as aesthetics maintenence, long-term stability, faster return to orthodontic treatment, and improved bone healing. However, there are some contraindications when the patient presents severe crowding, roots of the canine and lateral incisor are converging and in patients who will undergo to protraction with facial mask.

  11. Partial-wave expansions of angular spectra of plane waves.

    Science.gov (United States)

    Lock, James A

    2006-11-01

    Focused electromagnetic beams are frequently modeled by either an angular spectrum of plane waves or a partial-wave sum of spherical multipole waves. The connection between these two beam models is explored here. The partial-wave expansion of an angular spectrum containing evanescent components is found to possess only odd partial waves. On the other hand, the partial-wave expansion of an alternate angular spectrum constructed so as to be free of evanescent components contains all partial waves but describes a propagating beam with a small amount of standing-wave component mixed in. A procedure is described for minimizing the standing-wave component so as to more accurately model a purely forward propagating experimental beam.

  12. Graphite expansion committee meeting of January 7, 1947

    Energy Technology Data Exchange (ETDEWEB)

    Woods, W.K.

    1947-02-19

    The fourteenth meeting of the Graphite Expansion Committee was held on February 7, 1947. Laboratory studies indicate that either the graphite thermocouples are reading low or that annealing effects at elevated temperatures within the pile are much greater than those encountered In the laboratory. Current difficulties with operation of some of the horizontal and vertical control rods seem to be attributable to graphite expansion, though no complete understanding of the phenomena has been obtained and one is unable to predict the time required for similar difficulties to develop in other rods. Changes in clearance between process tubes and pile graphite in the D Pile have been erratic in nature but have averaged much less than had been anticipated. The negligible decrease in clearance for central tubes indicates that the expanding cross-wise graphite layers are slipping with respect to the graphite layers which contain process tubes.

  13. Expansion of interatomic distances in platinum catalyst nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Du, K. [Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016 (China)] [Department of Materials Science and Engineering, Case Western Reserve University, Cleveland, OH 44106 (United States); Ernst, F., E-mail: frank.ernst@case.edu [Department of Materials Science and Engineering, Case Western Reserve University, Cleveland, OH 44106 (United States); Pelsozy, M.C. [Department of Chemical Engineering, Case Western Reserve University, Cleveland, OH 44106 (United States); Barthel, J.; Tillmann, K. [Ernst Ruska-Centrum fuer Mikroskopie und Spektroskopie mit Elektronen (ER-C) and Institut fuer Festkoerperforschung, Forschungszentrum Juelich GmbH, Juelich (Germany)

    2010-02-15

    We study the atomistic structure of Pt catalyst nanoparticles using HRTEM (high-resolution transmission electron microscopy). The particles exhibit a faceted, cubo-octahedral shape, extended planar defects, and mono-atomic surface steps. HRTEM imaging with negative spherical aberration yielded atomic-resolution images with a minimum of artifacts. Combining digital image processing, quantitative image analysis, and HRTEM image simulations to determine local variations of the spacing between neighboring Pt atom columns, we have found an expansion of the lattice parameter in the particle core and even larger, locally varying expansion of Pt-Pt next-neighbor distances at the particle surface. The latter likely originates from an amorphous oxide on the nanoparticle surface and/or dissolution of oxygen on subsurface sites. These structural features may significantly impact the catalytic activity of Pt nanoparticles.

  14. QED in d=3 from the epsilon-expansion.

    CERN Multimedia

    CERN. Geneva

    2015-01-01

    In my talk, based on the recent work 1508.06278, I will consider the Renormalization Group flow of Quantum Electrodynamics in d=3 coupled to N_f flavors of fermions. For N_f smaller than a critical value N_f^c, chiral symmetry breaking is believed to take place. For N_f > N_f^c, the theory flows to an interacting fixed point that can be studied in the epsilon-expansion, using the fixed point in d=4-2\\epsilon. I will discuss the computation of the anomalous dimensions of fermion bilinears and quadrilinear operators, as well as some more conceptual aspects concerning the enhancement of global symmetries in d=3. For small N_f, a quadrilinear operator can become relevant in the IR and destabilize the fixed point. Therefore, the epsilon-expansion can be used to estimate N_f^c.

  15. Polyglutamine expansion in huntingtin increases its insertion into lipid bilayers.

    Science.gov (United States)

    Kegel, Kimberly B; Schewkunow, Vitali; Sapp, Ellen; Masso, Nicholas; Wanker, Erich E; DiFiglia, Marian; Goldmann, Wolfgang H

    2009-09-25

    An expanded polyglutamine (Q) tract (>37Q) in huntingtin (htt) causes Huntington disease. Htt associates with membranes and polyglutamine expansion in htt may alter membrane function in Huntington disease through a mechanism that is not known. Here we used differential scanning calorimetry to examine the effects of polyQ expansion in htt on its insertion into lipid bilayers. We prepared synthetic lipid vesicles composed of phosphatidylcholine and phosphatidylethanolamine and tested interactions of htt amino acids 1-89 with 20Q, 32Q or 53Q with the vesicles. GST-htt1-89 with 53Q inserted into synthetic lipid vesicles significantly more than GST-htt1-89 with 20Q or 32Q. We speculate that by inserting more into cell membranes, mutant huntingtin could increase disorder within the lipid bilayer and thereby disturb cellular membrane function.

  16. Stellarator expansion methods for MHD equilibrium and stability calculations

    Energy Technology Data Exchange (ETDEWEB)

    Lynch, V.E.; Charlton, L.A.; Hicks, H.R.; Holmes, J.A.; Carreras, B.A.; Hender, T.C.; Garcia, L.

    1986-03-01

    Two methods for performing stellarator expansion, or average method, MHD calculations are described. The first method includes the calculation of vacuum, equilibrium, and stability, using the Greene and Johnson stellarator expansion in which the equilibrium is reduced to a 2-D problem by averaging over the geometric toroidal angle in real space coordinates. In the second method, the average is performed in a system of vacuum magnetic coordinates. Both methods are implemented to utilize realistic vacuum field information, making them applicable to configuration studies and machine design, as well as to basic research. Illustrative examples are presented to detail the sensitivities of the calculations to physical parameters and to show numerical convergence and the comparison of these methods with each other and with other methods.

  17. The expansion of the universe observed with supernovae.

    Science.gov (United States)

    Astier, Pierre

    2012-11-01

    Over the last 20 years, supernovae have become a key tool to constrain the expansion history of the Universe through the construction of Hubble diagrams, using luminosity distances to supernovae belonging to the 'Ia' subtype. This technique was key for the discovery that the expansion of the Universe is now accelerating. We review the principle and difficulties of the measurements, the classification and diversity of supernovae, and the physics of explosion. We discuss the systematic uncertainties affecting the cosmological conclusions with some emphasis on photometric calibration. We describe the major supernova cosmology surveys, the presented analyses and their conclusions, together with the present status of the field. We conclude on the expectations for the near future.

  18. Dissipative effects in the expansion of the universe. I, II.

    Science.gov (United States)

    Matzner, R. A.; Misner, C. W.

    1972-01-01

    Consideration of dissipative processes in anisotropic homogeneous world models, showing that dissipation reduces the anisotropy. The viscosity approximation and its range of applicability is discussed. Examples are presented which have been calculated by the use of a simple approximation to the collision-time method, using the cross section appropriate to weak interaction neutrino scattering. It is found that such dissipation is quite effective except for one particular cosmological model which is axisymmetric and in which the entire expansion of the model is taken up by expansion along the axis. A detailed multicomponent model is developed for dissipative processes in Euclidean homogeneous cosmological models. These processes involve neutrinos which might have long mean free times in interaction with other constituents which are thermalized by electromagnetic interactions, and whose weak interactions produce thermal neutrinos.

  19. New constraints on the early expansion history of the universe.

    Science.gov (United States)

    Hojjati, Alireza; Linder, Eric V; Samsing, Johan

    2013-07-26

    Cosmic microwave background measurements have pushed to higher resolution, lower noise, and more sky coverage. These data enable a unique test of the early Universe's expansion rate and constituents such as effective number of relativistic degrees of freedom and dark energy. Using the most recent data from Planck and WMAP9, we constrain the expansion history in a model-independent manner from today back to redshift z=10(5). The Hubble parameter is mapped to a few percent precision, limiting early dark energy and extra relativistic degrees of freedom within a model-independent approach to 2%-16% and 0.71 equivalent neutrino species, respectively (95% C.L.). Within dark radiation, barotropic ether, and Doran-Robbers models, the early dark energy constraints are 3.3%, 1.9%, and 1.2%, respectively.

  20. A dynamic trinucleotide repeat (TNR) expansion in the DMD gene.

    Science.gov (United States)

    Kekou, Kyriaki; Sofocleous, Christalena; Papadimas, George; Petichakis, Dimitris; Svingou, Maria; Pons, Roser-Maria; Vorgia, Pelagia; Gika, Artemis; Kitsiou-Tzeli, Sophia; Kanavakis, Emmanuel

    2016-08-01

    Dystrophinopathies are allelic X-linked myopathies caused by large deletions/duplications or small lesions along the DMD gene. An unexpected dynamic trinucleotide (GAA) expansion, ranging from ∼59 to 82 pure GAA repeats, within the DMD intron 62, was revealed to segregate through three family generations. From the pedigree, two female patients were referred for DMD investigation due to chronic myopathy and a muscle biopsy compatible with dystrophinopathy. As the size of the GAA repeat is limited to 11-33 within the general population our findings may provide a novel insight towards a Trinucleotide Repeat Expansion. Whether this TNR has an impact on the reported phenotype remains to be resolved. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Heat kernel expansion in the background field formalism

    CERN Document Server

    Barvinsky, Andrei

    2015-01-01

    Heat kernel expansion and background field formalism represent the combination of two calculational methods within the functional approach to quantum field theory. This approach implies construction of generating functionals for matrix elements and expectation values of physical observables. These are functionals of arbitrary external sources or the mean field of a generic configuration -- the background field. Exact calculation of quantum effects on a generic background is impossible. However, a special integral (proper time) representation for the Green's function of the wave operator -- the propagator of the theory -- and its expansion in the ultraviolet and infrared limits of respectively short and late proper time parameter allow one to construct approximations which are valid on generic background fields. Current progress of quantum field theory, its renormalization properties, model building in unification of fundamental physical interactions and QFT applications in high energy physics, gravitation and...

  2. Asymptotic chaos expansions in finance theory and practice

    CERN Document Server

    Nicolay, David

    2014-01-01

    Stochastic instantaneous volatility models such as Heston, SABR or SV-LMM have mostly been developed to control the shape and joint dynamics of the implied volatility surface. In principle, they are well suited for pricing and hedging vanilla and exotic options, for relative value strategies or for risk management. In practice however, most SV models lack a closed form valuation for European options. This book presents the recently developed Asymptotic Chaos Expansions methodology (ACE) which addresses that issue. Indeed its generic algorithm provides, for any regular SV model, the pure asymptotes at any order for both the static and dynamic maps of the implied volatility surface. Furthermore, ACE is programmable and can complement other approximation methods. Hence it allows a systematic approach to designing, parameterising, calibrating and exploiting SV models, typically for Vega hedging or American Monte-Carlo. Asymptotic Chaos Expansions in Finance illustrates the ACE approach for single underlyings (suc...

  3. A Cohen-Type Inequality for Jacobi-Sobolev Expansions

    Directory of Open Access Journals (Sweden)

    Bujar Xh. Fejzullahu

    2008-02-01

    Full Text Available Let μ be the Jacobi measure supported on the interval [-1, 1]. Let us introduce the Sobolev-type inner product 〈f,g〉=∫−11f(xg(xdμ(x+Mf(1g(1+Nf'(1g'(1, where M,N≥0. In this paper we prove a Cohen-type inequality for the Fourier expansion in terms of the orthonormal polynomials associated with the above Sobolev inner product. We follow Dreseler and Soardi (1982 and Markett (1983 papers, where such inequalities were proved for classical orthogonal expansions.

  4. Microscopic-Macroscopic Mass Calculations with Wigner-Kirkwood expansion

    Energy Technology Data Exchange (ETDEWEB)

    Bhagwat, A [UM-DAE Centre for Excellence in Basic Sciences, Mumbai 400 098 (India); Vinas, X; Centelles, M [Departament d' Estructura i Constituents de la Materia and Institut de Ciencies del Cosmos, Facultat de Fisica, Universitat de Barcelona, Diagonal 647, E-08028 Barcelona (Spain); Wyss, R [KTH (Royal Institute of Technology), Alba Nova University Center, Department of Nuclear Physics, S-10691 Stockholm (Sweden); Schuck, P, E-mail: ameeya@cbs.ac.in [Institut de Physique Nucleaire, IN2P3-CNRS, Universite Paris-Sud, F-91406 Orsay Cedex (France)

    2011-09-16

    The systematic study and calculation of ground state nuclear masses continues to be one of the active and important areas of research in nuclear physics. The present work is an attempt to determine the ground state masses of nuclei spanning the entire periodic table, using the Microscopic-Macroscopic approach. The semi-classical Wigner-Kirkwood (WK) h expansion method is used to calculate shell corrections for spherical and deformed nuclei. The expansion is achieved upto the fourth order in h. The shell corrections, along with the pairing energies obtained by using the Lipkin-Nogami scheme, constitute the microscopic part of the nuclear masses. The macroscopic part is obtained from a liquid drop formula with six adjustable parameters. It is shown that the Microscopic-Macroscopic mass calculation thus achieved, yields reliable description of ground state masses of nuclei across the periodic table. The present status of the WK mass calculations and the possible future perspectives are discussed.

  5. WASP and electricity capacity expansion planning for emerging countries

    Energy Technology Data Exchange (ETDEWEB)

    Allentuck, J

    1980-11-01

    The WIEN Automatic System Planning Package (WASP) is typical of electrical generation capacity expansion planning models in general use today. It was developed by the Tennessee Valley Authority (TVA) for the International Atomic Energy Agency (IAEA) hence the name WIEN. It is available without charge to member states. Assistance in its use is available from IAEA staff and in addition it is well documented. The user of WASP should be aware of its uses and limitations especially, though not exclusively, in its application to emerging countries. This paper presents an overview of capacity expansion planning and its place in the economic planning process with reference to the emerging countries; describes in a general way the use of WASP; cautions care in the interpretation of WASP results; and suggests the way in which WASP can be used to assess innovative electric generating technologies.

  6. Elements of the niche for adult stem cell expansion.

    Science.gov (United States)

    Redondo, Patricia A; Pavlou, Marina; Loizidou, Marilena; Cheema, Umber

    2017-01-01

    Adult stem cells are crucial for tissue homeostasis. These cells reside within exclusive locations in tissues, termed niches, which protect adult stem cell fidelity and regulate their many functions through biophysical-, biochemical- and cellular-mediated mechanisms. There is a growing understanding of how these mechanisms and their components contribute towards maintaining stem cell quiescence, self-renewal, expansion and differentiation patterns. In vitro expansion of adult stem cells is a powerful tool for understanding stem cell biology, and for tissue engineering and regenerative medicine applications. However, it is technically challenging, since adult stem cell removal from their native microenvironment has negative repercussions on their sustainability. In this review, we overview specific elements of the biomimetic niche and how recreating such elements can help in vitro propagation of adult stem cells.

  7. Economic viability of transmission capacity expansion at high wind penetrations

    DEFF Research Database (Denmark)

    Østergaard, Poul Alberg

    2005-01-01

    With growing wind power penetrations in many countries, grid and system integration becomes more and more important issues. This is particularly the case in countries or regions with good wind resources as well as substantial installed wind power capacity as found in e.g. Northern Europe. At 20......% penetration in Western Denmark, the issue is pertinent here in relation to future plans of further expansion which is planned in accordance with the Danish Government’s climate change mitigation initiatives. This paper analyses the potential economic benefit of selling excess electricity production...... investments and analyses of the Nord Pool price variations. The analyses are done for varying degrees of wind power penetrations ranging from 20% of the West Danish electricity demand up to 100% of the demand. The analyses demonstrate, that while there is an economic potential for some expansion in some years...

  8. Transmission Network Expansion Planning Considering Desired Generation Security

    Directory of Open Access Journals (Sweden)

    Samaneh GOLESTANI

    2014-02-01

    Full Text Available Transmission Network Expansion Planning (TNEP is an important part of power system planning in both conventional and new structured power market. Its goal is to minimize the network construction and operational cost while satisfying the demand increase, considering technical and economic conditions. Planning algorithm in this paper consisted of two stages. The former specifies highly uncertain lines and probability of congestion, considering desired generation security level (e.g. N-2 generation security level. The latter determines the optimal expansion capacity of existing lines. Splitting required capacity for reinforcement of weak lines due to desired generation security level simplifies the TNEP problem. In addition, it monitors the impact of generation uncertainty on transmission lines. Simulation results of the proposed idea are presented for IEEE-RTS-24bus network.

  9. Transmission Network Expansion Planning Considering Phase-Shifter Transformers

    Directory of Open Access Journals (Sweden)

    Celso T. Miasaki

    2012-01-01

    Full Text Available This paper presents a novel mathematical model for the transmission network expansion planning problem. Main idea is to consider phase-shifter (PS transformers as a new element of the transmission system expansion together with other traditional components such as transmission lines and conventional transformers. In this way, PS are added in order to redistribute active power flows in the system and, consequently, to diminish the total investment costs due to new transmission lines. Proposed mathematical model presents the structure of a mixed-integer nonlinear programming (MINLP problem and is based on the standard DC model. In this paper, there is also applied a specialized genetic algorithm aimed at optimizing the allocation of candidate components in the network. Results obtained from computational simulations carried out with IEEE-24 bus system show an outstanding performance of the proposed methodology and model, indicating the technical viability of using these nonconventional devices during the planning process.

  10. Review article: volume expansion in patients with cirrhosis

    DEFF Research Database (Denmark)

    Henriksen, Jens Henrik Sahl; Kiszka-Kanowitz, Marianne; Bendtsen, Flemming

    2002-01-01

    in some aspects differently from healthy subjects, owing to their disturbed circulatory function and neurohormonal activation. Thus the increase in cardiac output and suppression of the renin-angiotensin-aldosterone system and sympathetic nervous system during volume expansion may be somewhat blunted......, and in advanced cirrhosis, especially the non-central parts of the circulation, including the splanchnic blood volume, are expanded by a volume load. Infusion of oncotic material (preferably albumin) is important in the prevention of post-paracentesis circulatory dysfunction. In conclusion, volume expansion...... in advanced cirrhosis is qualitatively and quantitatively different from that of healthy subjects, and in those with early cirrhosis. Timely handling is essential, but difficult as it is a balance between the risks of excess extravascular volume loading and further circulatory dysfunction in these patients...

  11. Rapid, global demographic expansions after the origins of agriculture.

    Science.gov (United States)

    Gignoux, Christopher R; Henn, Brenna M; Mountain, Joanna L

    2011-04-12

    The invention of agriculture is widely assumed to have driven recent human population growth. However, direct genetic evidence for population growth after independent agricultural origins has been elusive. We estimated population sizes through time from a set of globally distributed whole mitochondrial genomes, after separating lineages associated with agricultural populations from those associated with hunter-gatherers. The coalescent-based analysis revealed strong evidence for distinct demographic expansions in Europe, southeastern Asia, and sub-Saharan Africa within the past 10,000 y. Estimates of the timing of population growth based on genetic data correspond neatly to dates for the initial origins of agriculture derived from archaeological evidence. Comparisons of rates of population growth through time reveal that the invention of agriculture facilitated a fivefold increase in population growth relative to more ancient expansions of hunter-gatherers.

  12. On the asymptotic expansion of the Bergman kernel

    Science.gov (United States)

    Seto, Shoo

    Let (L, h) → (M, o) be a polarized Kahler manifold. We define the Bergman kernel for H0(M, Lk), holomorphic sections of the high tensor powers of the line bundle L. In this thesis, we will study the asymptotic expansion of the Bergman kernel. We will consider the on-diagonal, near-diagonal and far off-diagonal, using L2 estimates to show the existence of the asymptotic expansion and computation of the coefficients for the on and near-diagonal case, and a heat kernel approach to show the exponential decay of the off-diagonal of the Bergman kernel for noncompact manifolds assuming only a lower bound on Ricci curvature and C2 regularity of the metric.

  13. Two Integrator Loop Filters: Generation Using NAM Expansion and Review

    Directory of Open Access Journals (Sweden)

    Ahmed M. Soliman

    2010-01-01

    Full Text Available Systematic synthesis method to generate a family of two integrator loop filters based on nodal admittance matrix (NAM expansion is given. Eight equivalent circuits are obtained; six of them are new. Each of the generated circuits uses two grounded capacitors and employs two current conveyors (CCII or two inverting current conveyors (ICCII or a combination of both. The NAM expansion is also used to generate eight equivalent grounded passive elements two integrator loop filters using differential voltage current conveyor (DVCC; six of them are new. Changing the input port of excitation, two new families of eight unity gain lowpass filter circuits each using two CCII or ICCII or combination of both or two DVCC are obtained.

  14. EXPANSION OF RUSSIAN MNCs CONTINUES: THE M&A ROAD

    Directory of Open Access Journals (Sweden)

    CLAUDIA ISAC

    2013-12-01

    Full Text Available This paper focuses on the expansion of Russian MNCs in the world and especially in Europe. Thus, after an introduction about the role of MNCs in the context of economic globalization we have presented theoretically the expansion levers of MNCs through mergers and acquisitions. The largest part of the work aims at analyzing the way Russian MNCs were able to expand their activities in most countries in Europe and North America, the allocation of foreign investments in the economic sectors in which MNCs are prevailing and especially in the field of extraction and processing such natural resources as gas, oil, coal and steel. At the end of the paper we have outlined a structure of MNCs and we have pointed out the importance of these companies for the economic development and growth.

  15. The Elusive Coefficients of Thermal Expansion in PBX 9502

    Energy Technology Data Exchange (ETDEWEB)

    C.B. Skidmore; T.A. Butler; C.W. Sandoval

    2003-05-01

    PBX 9502 has been in war reserve service for over two decades. Ninety-five percent of the solid phase of this insensitive high explosive is composed of energetic crystallites designated as TATB (1,3,5-triamino-2,4,6-trinitrobenzene), held together by the remaining solid fraction--an inert, polymeric binder named Kel-F 800. The unusual combination of extreme insensitivity and adequate performance characteristics is not the only enigmatic feature of such TATB-based materials. In this report, we describe the difficulty and progress to date in reliably determining the coefficients of thermal expansion for consolidated components of PBX 9502. We provide bulk linear coefficient of thermal expansion (CTE) values for PBX 9502 consolidated to a density of approximately 1.890 g/cm{sup 3} and offer a simple set of equations for calculating dimensional changes for temperatures from 218 to 347 K (-55 C to 74 C).

  16. Expansion/Facemask Treatment of an Adult Class III Malocclusion

    OpenAIRE

    Jackson, Gregory W.; Kravitz, Neal D.

    2014-01-01

    The orthodontic treatment of class III malocclusion with a maxillary deficiency is often treated with maxillary protraction with or without expansion. Skeletal and dental changes have been documented which have combined for the protraction of the maxilla and the correction of the class III malocclusion. Concerning the ideal time to treat a developing class III malocclusion, studies have reported that, although early treatment may be the most effective, face mask therapy can provide a viable o...

  17. General Relativity eliminates Dark Energy, Dark Matter and Universal Expansion

    OpenAIRE

    Bartlett, Rodney

    2018-01-01

    This letter was rejected by International Knowledge Press because "we are unable to conclude that these findings would warrant publication in this journal." The letter is suggesting that dark energy, dark matter and universal expansion are intimately related. However, they aren't viewed as revolutions in cosmology which are essential to a complete understanding of the modern universe. They are instead viewed as properties which need to be added to the cosmos when Einstein...

  18. A phenomenological model of starch expansion by extrusion

    OpenAIRE

    2015-01-01

    The expansion phenomenon is a key-point of the development of extruded starch based composites. During extrusion, the molten material is forced through a die so that the sudden pressure drop causes part of the water to vaporize, giving an expanded cellular structure. The knowledge of the cellular structure is important because it impacts the mechanical properties of the foams, its texture, etc1. The moisture is lost due to evaporation and heat transfer, as the material cools down. Thus, the m...

  19. A phenomenological model of starchy materials expansion by extrusion

    OpenAIRE

    2015-01-01

    During extrusion of starchy products, the molten material is forced through a die so that the sudden pressure drop causes part of the water to vaporize, giving an expanded cellular structure. The moisture is lost due to evaporation and heat transfer, as the material cools down. Thus, the material crosses glass transition Tg and becomes solid. No simple deterministic model is available to describe satisfactory dynamic, multiphysic and multiphase phenomena during expansion. Current models are...

  20. Analysis of volume expansion data for periclase, lime, corundum ...

    Indian Academy of Sciences (India)

    where K0 and K0 are isothermal bulk modulus and its pressure derivative both at P = 0. Equations (7)–(9) corre- spond to (3)–(5), respectively and are quadratic equations in. [(V/V0) – 1]. On solving these equations we get the follow- ing expressions for volume expansion in terms of thermal pressure. V. V0. −1 = 1. (. K0 + 1. ).

  1. Comment on "Accelerating cosmological expansion from shear and bulk viscosity"

    CERN Document Server

    Giovannini, Massimo

    2015-01-01

    In a recent Letter [Phys. Rev. Lett. 114 091301 (2105)] the cause of the acceleration of the present Universe has been identified with the shear viscosity of an imperfect relativistic fluid even in the absence of any bulk viscous contribution. The gist of this comment is that the shear viscosity, if anything, can only lead to an accelerated expansion over sufficiently small scales well inside the Hubble radius.

  2. Accelerating cosmological expansion from shear and bulk viscosity

    CERN Document Server

    Floerchinger, Stefan; Wiedemann, Urs Achim

    2015-01-01

    The dissipation of energy from local velocity perturbations in the cosmological fluid affects the time evolution of spatially averaged fluid dynamic fields and the cosmological solution of Einstein's field equations. We show how this backreaction effect depends on shear and bulk viscosity and other material properties of the dark sector, as well as the spectrum of perturbations. If sufficiently large, this effect could account for the acceleration of the cosmological expansion.

  3. On the convergence of quantum resonant-state expansion

    Energy Technology Data Exchange (ETDEWEB)

    Brown, J. M.; Bahl, A. [College of Optical Sciences, University of Arizona, 1630 East University Boulevard, Tucson, Arizona 85721 (United States); Jakobsen, P. [Department of Mathematics and Statistics, University of Tromsø, Tromsø (Norway); Moloney, J. V.; Kolesik, M. [College of Optical Sciences, University of Arizona, 1630 East University Boulevard, Tucson, Arizona 85721 (United States); Arizona Center for Mathematical Sciences, University of Arizona, Tucson, Arizona 85721 (United States)

    2016-03-15

    Completeness of the system of Stark resonant states is investigated for a one-dimensional quantum particle with the Dirac-delta potential exposed to an external homogeneous field. It is shown that the resonant series representation of a given wavefunction converges on the negative real axis while the series diverges on the positive axis. Despite the divergent nature of the resonant expansion, good approximations can be obtained in a compact spatial domain.

  4. Cultural Historical Activity Theory, Expansive Learning and Agency ...

    African Journals Online (AJOL)

    This paper reports on how Cultural Historical Activity Theory was used to identify and analyse contradictions; model and ... CuLTurAL HisToriCAL ACTiviTy THEory, ExPAnsivE LEArning & AgEnCy in PErmACuLTurE 151. Table 1. ..... sell vegetables and the money is used for paying the orphans' school fees. SCOPE also ...

  5. Query Expansion Using SNOMED-CT and Weighing Schemes

    Science.gov (United States)

    2014-11-01

    For this research, we have used SNOMED-CT along with UMLS Methathesaurus as our ontology in medical domain to expand the queries. General Terms...CT along with UMLS Methathesaurus as our ontology in medical domain to expand the queries. 15. SUBJECT TERMS 16. SECURITY CLASSIFICATION OF: 17...University of the Basque country discuss their finding on query expansion using external sources headlined by Unified Medical Language System ( UMLS

  6. Finite and Infinite Arithmetic Progressions Related to Beta-Expansion

    Directory of Open Access Journals (Sweden)

    Bing Li

    2014-01-01

    Full Text Available Let 1<β<2 and ε(x,β be the β-expansion of x∈[0,1. Denote by Aβ(x the set of positions where the digit 1 appears in ε(x,β. We consider the sets of points x such that Aβ(x contains arbitrarily long arithmetic progressions and includes infinite arithmetic progressions, respectively. Their sizes are investigated from the topological, metric, and dimensional viewpoints.

  7. Dressed skeleton expansion and the coupling scale ambiguity problem

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Hung Jung.

    1992-09-01

    Perturbative expansions in quantum field theories are usually expressed in powers of a coupling constant. In principle, the infinite sum of the expansion series is independent of the renormalization scale of the coupling constant. In practice, there is a remnant dependence of the truncated series on the renormalization scale. This scale ambiguity can severely restrict the predictive power of theoretical calculations. The dressed skeleton expansion is developed as a calculational method which avoids the coupling scale ambiguity problem. In this method, physical quantities are expressed as functional expansions in terms of a coupling vertex function. The arguments of the vertex function are given by the physical momenta of each process. These physical momenta effectively replace the unspecified renormalization scale and eliminate the ambiguity problem. This method is applied to various field theoretical models and its main features and limitations are explored. For quantum chromodynamics, an expression for the running coupling constant of the three-gluon vertex is obtained. The effective coupling scale of this vertex is shown to be essentially given by [mu][sup 2] [approximately] Q[sub min][sup 2]Q[sub med][sup 2]/Q[sub max][sup 2] where Q[sub min][sup 2]Q[sub med][sup 2]/Q[sub max][sup 2] are respectively the smallest, the next-to-smallest and the largest scale among the three gluon virtualities. This functional form suggests that the three-gluon vertex becomes non-perturbative at asymmetric momentum configurations. Implications for four-jet physics is discussed.

  8. Dressed skeleton expansion and the coupling scale ambiguity problem

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Hung Jung

    1992-09-01

    Perturbative expansions in quantum field theories are usually expressed in powers of a coupling constant. In principle, the infinite sum of the expansion series is independent of the renormalization scale of the coupling constant. In practice, there is a remnant dependence of the truncated series on the renormalization scale. This scale ambiguity can severely restrict the predictive power of theoretical calculations. The dressed skeleton expansion is developed as a calculational method which avoids the coupling scale ambiguity problem. In this method, physical quantities are expressed as functional expansions in terms of a coupling vertex function. The arguments of the vertex function are given by the physical momenta of each process. These physical momenta effectively replace the unspecified renormalization scale and eliminate the ambiguity problem. This method is applied to various field theoretical models and its main features and limitations are explored. For quantum chromodynamics, an expression for the running coupling constant of the three-gluon vertex is obtained. The effective coupling scale of this vertex is shown to be essentially given by {mu}{sup 2} {approximately} Q{sub min}{sup 2}Q{sub med}{sup 2}/Q{sub max}{sup 2} where Q{sub min}{sup 2}Q{sub med}{sup 2}/Q{sub max}{sup 2} are respectively the smallest, the next-to-smallest and the largest scale among the three gluon virtualities. This functional form suggests that the three-gluon vertex becomes non-perturbative at asymmetric momentum configurations. Implications for four-jet physics is discussed.

  9. Belief Expansion, Contextual Fit and the Reliability of Information Sources

    OpenAIRE

    Hartmann, Stephan; Bovens, L

    2001-01-01

    We develop a probabilistic criterion for belief expansion that is sensitive to the degree of contextual fit of the new information to our belief set as well as to the reliability of our information source. We contrast our approach with the success postulate in AGM-style belief revision and show how the idealizations in our approach can be relaxed by invoking Bayesian-Network models.Article

  10. Stable hyper-pooling and query expansion for event detection

    OpenAIRE

    Douze, Matthijs; Revaud, Jerome; Schmid, Cordelia; Jegou, Herve

    2013-01-01

    International audience; This paper makes two complementary contributions to event retrieval in large collections of videos. First, we propose hyper-pooling strategies that encode the frame descriptors into a representation of the video sequence in a stable manner. Our best choices compare favorably with regular pooling techniques based on k-means quantization. Second, we introduce a technique to improve the ranking. It can be interpreted either as a query expansion method or as a similarity a...

  11. Complete mitochondrial genomes reveal neolithic expansion into Europe.

    Directory of Open Access Journals (Sweden)

    Qiaomei Fu

    Full Text Available The Neolithic transition from hunting and gathering to farming and cattle breeding marks one of the most drastic cultural changes in European prehistory. Short stretches of ancient mitochondrial DNA (mtDNA from skeletons of pre-Neolithic hunter-gatherers as well as early Neolithic farmers support the demic diffusion model where a migration of early farmers from the Near East and a replacement of pre-Neolithic hunter-gatherers are largely responsible for cultural innovation and changes in subsistence strategies during the Neolithic revolution in Europe. In order to test if a signal of population expansion is still present in modern European mitochondrial DNA, we analyzed a comprehensive dataset of 1,151 complete mtDNAs from present-day Europeans. Relying upon ancient DNA data from previous investigations, we identified mtDNA haplogroups that are typical for early farmers and hunter-gatherers, namely H and U respectively. Bayesian skyline coalescence estimates were then used on subsets of complete mtDNAs from modern populations to look for signals of past population expansions. Our analyses revealed a population expansion between 15,000 and 10,000 years before present (YBP in mtDNAs typical for hunters and gatherers, with a decline between 10,000 and 5,000 YBP. These corresponded to an analogous population increase approximately 9,000 YBP for mtDNAs typical of early farmers. The observed changes over time suggest that the spread of agriculture in Europe involved the expansion of farming populations into Europe followed by the eventual assimilation of resident hunter-gatherers. Our data show that contemporary mtDNA datasets can be used to study ancient population history if only limited ancient genetic data is available.

  12. A cluster expansion for interacting spin-flip processes

    Directory of Open Access Journals (Sweden)

    Campanino Massimo

    2017-01-01

    Full Text Available We consider a system of spin flip processes, one-for each point of ℤ${\\mathbb Z}$, interacting through an Ising type interaction. We construct a cluster expansion and prove that it is convergent when the intensity h of the spin-flip processes is sufficiently high. The system is relevant in the study of the ground state of a quantum Ising process with transverse magnetic field.

  13. Anisotropic ghost dark energy cosmological model with hybrid expansion law

    Science.gov (United States)

    Mahanta, Chandra Rekha; Sarma, Nitin

    2017-11-01

    In this paper, we study the anisotropic Bianchi type-VI0 metric filled with dark matter and anisotropic ghost dark energy. We have solved the Einstein's field equations by considering hybrid expansion law (HEL) for the average scale factor. It is found that at later times the universe becomes spatially homogeneous, isotropic and flat. From a state finder diagnosis, it is found that our model is having similar behavior like ɅCDM model at late phase of cosmic time.

  14. Geographic Expansion of Lyme Disease in Michigan, 2000?2014

    OpenAIRE

    Lantos, Paul M.; Tsao, Jean; Nigrovic, Lise E.; Auwaerter, Paul G.; Fowler, Vance G.; Ruffin, Felicia; Foster, Erik; Hickling, Graham

    2017-01-01

    Abstract Background. Most Lyme disease cases in the Midwestern United States are reported in Minnesota and Wisconsin. In recent years, however, a widening geographic extent of Lyme disease has been noted with evidence of expansion eastwards into Michigan and neighboring states with historically low incidence rates. Methods. We collected confirmed and probable cases of Lyme disease from 2000 through 2014 from the Michigan Department of Health and Human Services, entering them in a geographic i...

  15. Eigenvalues from power-series expansions: an alternative approach

    Energy Technology Data Exchange (ETDEWEB)

    Amore, Paolo [Facultad de Ciencias, Universidad de Colima, Bernal DIaz del Castillo 340, Colima, Colima (Mexico); Fernandez, Francisco M [INIFTA (UNLP, CCT La Plata-CONICET), Division Quimica Teorica, Diag. 113 y 64 (S/N), Sucursal 4, Casilla de Correo 16, 1900 La Plata (Argentina)], E-mail: paolo.amore@gmail.com, E-mail: fernande@quimica.unlp.edu.ar

    2009-02-20

    An appropriate rational approximation to the eigenfunction of the Schroedinger equation for anharmonic oscillators enables one to obtain the eigenvalue accurately as the limit of a sequence of roots of Hankel determinants. The convergence rate of this approach is greater than that for a well-established method based on power-series expansions weighted by a Gaussian factor with an adjustable parameter (the so-called Hill-determinant method)

  16. Rayleigh-Ritz variation method and connected-moments expansions

    Energy Technology Data Exchange (ETDEWEB)

    Amore, Paolo [Facultad de Ciencias, Universidad de Colima, Bernal DIaz del Castillo 340, Colima (Mexico); Fernandez, Francisco M [INIFTA (UNLP, CCT La Plata-CONICET), Division Quimica Teorica, Blvd 113 S/N, Sucursal 4, Casilla de Correo 16, 1900 La Plata (Argentina)], E-mail: fernande@quimica.unlp.edu.ar

    2009-11-15

    We compare the connected-moments expansion (CMX) with the Rayleigh-Ritz variational method in the Krylov space (RRK). As a benchmark model we choose the same two-dimensional anharmonic oscillator already treated earlier by means of the CMX. Our results show that the RRK converges more smoothly than the CMX. We also discuss the fact that the CMX is size consistent while the RRK is not.

  17. FY16 ISCP Nuclear Counting Facility Hardware Expansion Summary

    Energy Technology Data Exchange (ETDEWEB)

    Church, Jennifer A. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Kashgarian, Michaele [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Wooddy, Todd [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Haslett, Bob [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Torretto, Phil [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2016-09-15

    Hardware expansion and detector calibrations were the focus of FY 16 ISCP efforts in the Nuclear Counting Facility. Work focused on four main objectives: 1) Installation, calibration, and validation of 4 additional HPGe gamma spectrometry systems; including two Low Energy Photon Spectrometers (LEPS). 2) Re-Calibration and validation of 3 previously installed gamma-ray detectors, 3) Integration of the new systems into the NCF IT infrastructure, and 4) QA/QC and maintenance of current detector systems.

  18. Extended Thomas-Fermi expansion from nuclear linear response

    Energy Technology Data Exchange (ETDEWEB)

    Navarro, J. [IFIC, Centre Mixt CSIC, Universitat de Valencia, Avda Dr Moliner 50, E-46.100 Burjassot (Spain); Vinas, X. [Departamento Estructura i Constituents de la Materia, Facultat de Fisica, Universitat de Barcelona, Diagonal 645, E-08028 Barcelona (Spain)

    1996-09-01

    The coefficients of the successive h/2{pi}{sup 2} orders of the extended Thomas-Fermi expansion of the kinetic energy density are obtained to the leading order in the density inhomogeneities. This is done by comparing the corresponding static polarizability with the exact value in two cases: a non-interacting nuclear infinite system and symmetric nuclear matter with a Skyrme interaction. (author)

  19. Cranial expansion for shunt-induced craniostenosis. Case report ...

    African Journals Online (AJOL)

    Quelques patients atteints de fentes ventriculaires développent une craniosténose shunt induite provoquant une augmentation de la pression intracrânienne pendant que le cerveau se développe peuvant être mal interprété comme un problème de dysfonctionnement de shunt. L'expansion de voûte crânienne a été décrit ...

  20. DYNAMIC PROGRAMMING – EFFICIENT TOOL FOR POWER SYSTEM EXPANSION PLANNING

    Directory of Open Access Journals (Sweden)

    SIMO A.

    2015-03-01

    Full Text Available The paper isfocusing on dynamic programming use for power system expansion planning (EP – transmission network (TNEP and distribution network (DNEP. The EP problem has been approached from the retrospective and prospective point of view. To achieve this goal, the authors are developing two software-tools in Matlab environment. Two techniques have been tackled: particle swarm optimization (PSO and genetic algorithms (GA. The case study refers to Test 25 buses test power system developed within the Power Systems Department.