Application of the perfectly matched layer in 3-D marine controlled-source electromagnetic modelling
Li, Gang; Li, Yuguo; Han, Bo; Liu, Zhan
2018-01-01
In this study, the complex frequency-shifted perfectly matched layer (CFS-PML) in stretching Cartesian coordinates is successfully applied to 3-D frequency-domain marine controlled-source electromagnetic (CSEM) field modelling. The Dirichlet boundary, which is usually used within the traditional framework of EM modelling algorithms, assumes that the electric or magnetic field values are zero at the boundaries. This requires the boundaries to be sufficiently far away from the area of interest. To mitigate the boundary artefacts, a large modelling area may be necessary even though cell sizes are allowed to grow toward the boundaries due to the diffusion of the electromagnetic wave propagation. Compared with the conventional Dirichlet boundary, the PML boundary is preferred as the modelling area of interest could be restricted to the target region and only a few absorbing layers surrounding can effectively depress the artificial boundary effect without losing the numerical accuracy. Furthermore, for joint inversion of seismic and marine CSEM data, if we use the PML for CSEM field simulation instead of the conventional Dirichlet, the modelling area for these two different geophysical data collected from the same survey area could be the same, which is convenient for joint inversion grid matching. We apply the CFS-PML boundary to 3-D marine CSEM modelling by using the staggered finite-difference discretization. Numerical test indicates that the modelling algorithm using the CFS-PML also shows good accuracy compared to the Dirichlet. Furthermore, the modelling algorithm using the CFS-PML shows advantages in computational time and memory saving than that using the Dirichlet boundary. For the 3-D example in this study, the memory saving using the PML is nearly 42 per cent and the time saving is around 48 per cent compared to using the Dirichlet.
Hu, Shuai; Gao, Taichang; Li, Hao; Yang, Bo; Jiang, Zidong; Liu, Lei; Chen, Ming
2017-10-01
The performance of absorbing boundary condition (ABC) is an important factor influencing the simulation accuracy of MRTD (Multi-Resolution Time-Domain) scattering model for non-spherical aerosol particles. To this end, the Convolution Perfectly Matched Layer (CPML), an excellent ABC in FDTD scheme, is generalized and applied to the MRTD scattering model developed by our team. In this model, the time domain is discretized by exponential differential scheme, and the discretization of space domain is implemented by Galerkin principle. To evaluate the performance of CPML, its simulation results are compared with those of BPML (Berenger's Perfectly Matched Layer) and ADE-PML (Perfectly Matched Layer with Auxiliary Differential Equation) for spherical and non-spherical particles, and their simulation errors are analyzed as well. The simulation results show that, for scattering phase matrices, the performance of CPML is better than that of BPML; the computational accuracy of CPML is comparable to that of ADE-PML on the whole, but at scattering angles where phase matrix elements fluctuate sharply, the performance of CPML is slightly better than that of ADE-PML. After orientation averaging process, the differences among the results of different ABCs are reduced to some extent. It also can be found that ABCs have a much weaker influence on integral scattering parameters (such as extinction and absorption efficiencies) than scattering phase matrices, this phenomenon can be explained by the error averaging process in the numerical volume integration.
Martin, Roland; Komatitsch, Dimitri; Bruthiaux, Emilien; Gedney, Stephen D.
2010-05-01
We present and discuss here two different unsplit formulations of the frequency shift PML based on convolution or non convolution integrations of auxiliary memory variables. Indeed, the Perfectly Matched Layer absorbing boundary condition has proven to be very efficient from a numerical point of view for the elastic wave equation to absorb both body waves with non-grazing incidence and surface waves. However, at grazing incidence the classical discrete Perfectly Matched Layer method suffers from large spurious reflections that make it less efficient for instance in the case of very thin mesh slices, in the case of sources located very close to the edge of the mesh, and/or in the case of receivers located at very large offset. In [1] we improve the Perfectly Matched Layer at grazing incidence for the seismic wave equation based on an unsplit convolution technique. This improved PML has a cost that is similar in terms of memory storage to that of the classical PML. We illustrate the efficiency of this improved Convolutional Perfectly Matched Layer based on numerical benchmarks using a staggered finite-difference method on a very thin mesh slice for an isotropic material and show that results are significantly improved compared with the classical Perfectly Matched Layer technique. We also show that, as the classical model, the technique is intrinsically unstable in the case of some anisotropic materials. In this case, retaining an idea of [2], this has been stabilized by adding correction terms adequately along any coordinate axis [3]. More specifically this has been applied to the spectral-element method based on a hybrid first/second order time integration scheme in which the Newmark time marching scheme allows us to match perfectly at the base of the absorbing layer a velocity-stress formulation in the PML and a second order displacement formulation in the inner computational domain.Our CPML unsplit formulation has the advantage to reduce the memory storage of CPML
Unconditionally stable perfectly matched layer boundary conditions
De Raedt, H.; Michielsen, K.
2007-01-01
A brief review is given of a systematic, product-formula based approach to construct unconditionally stable algorithms for solving the time-dependent Maxwell equations. The fundamental difficulties that arise when we want to incorporate uniaxial perfectly matched layer boundary conditions into this
Application of the perfectly matched layer in 2.5D marine controlled-source electromagnetic modeling
Li, Gang; Han, Bo
2017-09-01
For the traditional framework of EM modeling algorithms, the Dirichlet boundary is usually used which assumes the field values are zero at the boundaries. This crude condition requires that the boundaries should be sufficiently far away from the area of interest. Although cell sizes could become larger toward the boundaries as electromagnetic wave is propagated diffusively, a large modeling area may still be necessary to mitigate the boundary artifacts. In this paper, the complex frequency-shifted perfectly matched layer (CFS-PML) in stretching Cartesian coordinates is successfully applied to 2.5D frequency-domain marine controlled-source electromagnetic (CSEM) field modeling. By using this PML boundary, one can restrict the modeling area of interest to the target region. Only a few absorbing layers surrounding the computational area can effectively depress the artificial boundary effect without losing the numerical accuracy. A 2.5D marine CSEM modeling scheme with the CFS-PML is developed by using the staggered finite-difference discretization. This modeling algorithm using the CFS-PML is of high accuracy, and shows advantages in computational time and memory saving than that using the Dirichlet boundary. For 3D problem, this computation time and memory saving should be more significant.
Efficient and stable perfectly matched layer for CEM
Duru, Kenneth
2014-02-01
An efficient unsplit perfectly matched layer for numerical simulation of electromagnetic waves in unbounded domains is derived via a complex change of variables. In order to surround a Cartesian grid with the PML, the time-dependent PML requires only one (scalar) auxiliary variable in two space dimensions and six (scalar) auxiliary variables in three space dimensions. It is therefore cheap and straightforward to implement. We use Fourier and energy methods to prove the stability of the PML. We extend the stability result to a semi-discrete PML approximated by central finite differences of arbitrary order of accuracy and to a fully discrete problem for the \\'Leap-Frog\\' schemes. This makes precise the usefulness of the derived PML model for longtime simulations. Numerical experiments are presented, illustrating the accuracy and stability of the PML. © 2013 IMACS.
Cognitive Learning Styles: Can You Engineer a "Perfect" Match?
Khuzzan, Sharifah Mazlina Syed; Goulding, Jack Steven
2016-01-01
Education and training is widely acknowledged as being one of the key factors for leveraging organisational success. However, it is equally acknowledged that skills development and the acquisition of learning through managed cognitive approaches has yet to provide a "perfect" match. Whilst it is argued that an ideal learning scenario…
Op zoek naar de perfecte match in vrijwilligersland
Directory of Open Access Journals (Sweden)
Els van Gilst
2015-06-01
-to-face contact with a prospective volunteer. Specific attention to motives in interview protocols is important. The use of tests or even the development of alternative tests should also be (reconsidered. In the case of online brokerage, it is much harder to establish an accurate picture of motives. Online testing could offer a solution. However, interpretation possibilities are limited because test results cannot be supplemented with other information. This favours (for the time being face-to-face contact during online Matching.In addition, the phase model of volunteer brokerage provides volunteer centres with a framework to describe their brokerage activities. This can be useful when training (new employees and providing transparency for customers and funders.Op zoek naar de perfecte match in vrijwilligerslandDe vraag naar vrijwilligers neemt de laatste jaren sterk toe in Nederland. Dit heeft te maken met een strengere wet- en regelgeving, veranderende inzet van vrijwilligers en hervormingen in de zorg (Bekkers & Boezeman, 2009; Devilee, 2005; MOVISIE, 2014; Rutte & Samsom, 2012. Steunpunten vrijwilligerswerk kunnen als bemiddelaars bijdragen aan de regulering van de vraag naar vrijwilligers. De mate van succes van vrijwilligersbemiddeling is echter nog relatief beperkt. Uit literatuuronderzoek (Van Gilst et al., 2011 is bekend welke factoren bijdragen aan het succes van vrijwilligersbemiddeling. Dit artikel beschrijft de bemiddelingspraktijk van steunpunten vrijwilligerswerk en geeft aan wanneer en hoe de gevonden succesfactoren kunnen worden ingezet in deze bemiddelingspraktijk om het resultaat te verbeteren. De praktijkgegevens zijn afkomstig van een veldonderzoek onder steunpunten, vrijwilligers en organisaties die met vrijwilligers werken.
Perfectly Matched Layer (PML) for Transient Wave Propagation in a Moving Frame of Reference
DEFF Research Database (Denmark)
Madsen, Stine Skov; Krenk, Steen; Hededal, Ole
2013-01-01
In relation to the development of a Rolling Wheel Deflectometer (RWD), which is a non-destructive testing device for measuring pavement deflections, a finite element model for obtaining the soil/pavement response is developed. Absorbing boundary conditions are necessary in order to prevent...... reflections of the waves propagating through the soil due to the dynamic loading. The Perfectly Matched Layer (PML) has proven to be highly efficient when solving transient wave propagation problems in a fixed mesh. However, since the RWD is operating at traffic speeds, the load is moving with high speed...
The perfect match: Do criminal stereotypes bias forensic evidence analysis?
Smalarz, Laura; Madon, Stephanie; Yang, Yueran; Guyll, Max; Buck, Sarah
2016-08-01
This research provided the first empirical test of the hypothesis that stereotypes bias evaluations of forensic evidence. A pilot study (N = 107) assessed the content and consensus of 20 criminal stereotypes by identifying perpetrator characteristics (e.g., sex, race, age, religion) that are stereotypically associated with specific crimes. In the main experiment (N = 225), participants read a mock police incident report involving either a stereotyped crime (child molestation) or a nonstereotyped crime (identity theft) and judged whether a suspect's fingerprint matched a fingerprint recovered at the crime scene. Accompanying the suspect's fingerprint was personal information about the suspect of the type that is routinely available to fingerprint analysts (e.g., race, sex) and which could activate a stereotype. Participants most often perceived the fingerprints to match when the suspect fit the criminal stereotype, even though the prints did not actually match. Moreover, participants appeared to be unaware of the extent to which a criminal stereotype had biased their evaluations. These findings demonstrate that criminal stereotypes are a potential source of bias in forensic evidence analysis and suggest that suspects who fit criminal stereotypes may be disadvantaged over the course of the criminal justice process. (PsycINFO Database Record (c) 2016 APA, all rights reserved).
DEFF Research Database (Denmark)
Wøhlk, Sanne; Laporte, Gilbert
2017-01-01
The aim of this paper is to computationally compare several algorithms for the Minimum Cost Perfect Matching Problem on an undirected complete graph. Our work is motivated by the need to solve large instances of the Capacitated Arc Routing Problem (CARP) arising in the optimization of garbage...
Schulz, Andreas
2015-01-01
This work is devoted to the numerical analysis of time-domain linear Maxwell's equations in a discontinuous Galerkin discretization. We focus on Berenger's perfectly matched layer and have a detailed look at construction, well-posedness, and semi-discrete error analysis. We present an analytic solution to the system, that can be utilized to efficiently determine optimal parameter values for the layer and state a way to avoid an exponential growth in time of the semi-discrete error bound.
A perfect match? A postcolonial perspective on well educated refugees at the Danish labour market
DEFF Research Database (Denmark)
Andersen, Vibeke; Jensen, Iben
qualifying education they will be challenged by mechanisms of social exclusion in ongoing practices in the workplace. The paper aims to discuss how this situation – a perfect match between skills and demand for job - can be seen from a post colonial perspective. A post colonial perspective is referring......% of the refugees have a professional background in medicine, technical domains or engineering (The ministry of Immigration, Integration and Housing). In Denmark efforts of integrating refugees can be accommodated by the fact that there is a shortage of highly skilled labor – mainly in the area of engineering...
Minimum-weight perfect matching for non-intrinsic distances on the line
Delon, Julie; Salomon, Julien; Sobolevski, Andrei
2011-01-01
13 pages, figures in TiKZ, uses xcolor package; introduction and the concluding section have been expanded.; Consider a real line equipped with a (not necessarily intrinsic) distance. We deal with the minimum-weight perfect matching problem for a complete graph whose points are located on the line and whose edges have weights equal to distances along the line. This problem is closely related to one-dimensional Monge-Kantorovich trasnport optimization. The main result of the present note is a ...
Perfectly Matched Layer for the Wave Equation Finite Difference Time Domain Method
Miyazaki, Yutaka; Tsuchiya, Takao
2012-07-01
The perfectly matched layer (PML) is introduced into the wave equation finite difference time domain (WE-FDTD) method. The WE-FDTD method is a finite difference method in which the wave equation is directly discretized on the basis of the central differences. The required memory of the WE-FDTD method is less than that of the standard FDTD method because no particle velocity is stored in the memory. In this study, the WE-FDTD method is first combined with the standard FDTD method. Then, Berenger's PML is combined with the WE-FDTD method. Some numerical demonstrations are given for the two- and three-dimensional sound fields.
On absorbing boundary conditons for linearized Euler equations by a perfectly matched layer
International Nuclear Information System (INIS)
Hu, F.Q.
1996-01-01
Recently, Berenger introduced a perfectly matched layer (PML) technique for absorbing electromagnetic waves. In the present paper, a perfectly matched layer is proposed for absorbing out-going two-dimensional waves in a uniform mean flow, governed by linearized Euler equations. It is well known that the linearized Euler equations support acoustic waves, which travel with the speed of sound relative to the mean flow, and vorticity and entropy waves, which travel with the mean flow. The PML equations to be used at a region adjacent to the artificial boundary for absorbing these linear waves are defined. Plane wave solutions to the PML equations are developed and wave propagation and absorption properties are given. It is shown that the theoretical reflection coefficients at an interface between the Euler and PML domains are zero, independent of the angle of incidence and frequency of the waves. As such, the present study points out a possible alternative approach for absorbing outgoing waves of the Euler equations with little or no reflection. In actual computations, nonetheless, numerical reflection will still occur due to discretization and mesh truncation, depending on the thickness of the PML domains and absorption coefficients used. Numerical examples that demonstrate the validity of the proposed PML equations are presented. 17 refs., 13 figs
Directory of Open Access Journals (Sweden)
Cristian GEORGESCU
2005-01-01
Full Text Available The goal of this paper is to investigate how such a pattern matching could be performed on models,including the definition of the input language as well as the elaboration of efficient matchingalgorithms. Design patterns can be considered reusable micro-architectures that contribute to anoverall system architecture. Frameworks are also closely related to design patterns. Componentsoffer the possibility to radically change the behaviors and services offered by an application bysubstitution or addition of new components, even a long time after deployment. Software testing isanother aspect of reliable development. Testing activities mainly consist in ensuring that a systemimplementation conforms to its specifications.
Darvish, Amirashkan; Zakeri, Bijan; Radkani, Nafiseh
2018-03-01
A hybrid technique is studied in order to improve the performance of Convolutional Perfectly Matched Layer (CPML) in the Finite Difference Time Domain (FDTD) medium. This technique combines the first order of Higdon's annihilation equation as Absorbing Boundary Condition (ABC) with CPML to vanish the Perfect Electric Conductor (PEC) effects at the end of the CPML region. An optimization algorithm is required to find optimum parameters of the proposed absorber. In this investigation, the Particle Swarm Optimization (PSO) is utilized with two separate objective functions in order to minimize the average and peak value of relative error. Using a standard test, the overall performance of the proposed absorber is compared to the original CPML. The results clearly illustrate this method provides approximately 10 dB enhancements in CPML absorption error. The performance, memory and time requirement of the novel absorber, hybrid CPML (H-CPML), was analyzed during 2D and 3D tests and compared to most reported PMLs. The H-CPML requirement of computer resources is similar to CPML and can simply be implemented to truncate FDTD domains. Furthermore, an optimized set of parameters are provided to generalize the hybrid method.
Development of a perfect prognosis probabilistic model for ...
Indian Academy of Sciences (India)
A prediction model based on the perfect prognosis method was developed to predict the probability of lightning and probable time of its occurrence over the south-east Indian region. In the perfect prognosis method, statistical relationships are established using past observed data. For real time applications, the predictors ...
DEFF Research Database (Denmark)
Xie, Zhinan; Matzen, René; Cristini, Paul
2016-01-01
A time-domain Legendre spectral-element method is described for full-wave simulation of ocean acoustics models, i.e., coupled fluid-solid problems in unbounded or semi-infinite domains, taking into account shear wave propagation in the ocean bottom. The technique can accommodate range......-dependent and depth-dependent wave speed and density, as well as steep ocean floor topography. For truncation of the infinite domain, to efficiently absorb outgoing waves, a fluid-solid complex-frequency-shifted unsplit perfectly matched layer is introduced based on the complex coordinate stretching technique...... because the latter allows for implementation of high-order time schemes, leading to reduced numerical dispersion and dissipation, a topic of importance, in particular, in long-range ocean acoustics simulations. The method is validated for a two dimensional fluid-solid Pekeris waveguide and for a three...
Kim, Seungil
2010-01-01
In this paper, we study the spectrum of the operator which results when the Perfectly Matched Layer (PML) is applied in Cartesian geometry to the Laplacian on an unbounded domain. This is often thought of as a complex change of variables or "complex stretching." The reason that such an operator is of interest is that it can be used to provide a very effective domain truncation approach for approximating acoustic scattering problems posed on unbounded domains. Stretching associated with polar or spherical geometry lead to constant coefficient operators outside of a bounded transition layer and so even though they are on unbounded domains, they (and their numerical approximations) can be analyzed by more standard compact perturbation arguments. In contrast, operators associated with Cartesian stretching are non-constant in unbounded regions and hence cannot be analyzed via a compact perturbation approach. Alternatively, to show that the scattering problem PML operator associated with Cartesian geometry is stable for real nonzero wave numbers, we show that the essential spectrum of the higher order part only intersects the real axis at the origin. This enables us to conclude stability of the PML scattering problem from a uniqueness result given in a subsequent publication. © 2009 Elsevier Inc. All rights reserved.
A perfectly matched layer for the time-dependent wave equation in heterogeneous and layered media
Duru, Kenneth
2014-01-01
A mathematical analysis of the perfectly matched layer (PML) for the time-dependent wave equation in heterogeneous and layered media is presented. We prove the stability of the PML for discontinuous media with piecewise constant coefficients, and derive energy estimates for discontinuous media with piecewise smooth coefficients. We consider a computational setup consisting of smaller structured subdomains that are discretized using high order accurate finite difference operators for approximating spatial derivatives. The subdomains are then patched together into a global domain by a weak enforcement of interface conditions using penalties. In order to ensure the stability of the discrete PML, it is necessary to transform the interface conditions to include the auxiliary variables. In the discrete setting, the transformed interface conditions are crucial in deriving discrete energy estimates analogous to the continuous energy estimates, thus proving stability and convergence of the numerical method. Finally, we present numerical experiments demonstrating the stability of the PML in a layered medium and high order accuracy of the proposed interface conditions. © 2013 Elsevier Inc.
Stoffer, Remco; Sopaheluwakan, A.; Hammer, Manfred; van Groesen, Embrecht W.C.
2008-01-01
By combining Dirichlet to Neumann (DtN) operators and Perfectly Matched Layers (PML’s) as boundary conditions on a rectangular domain on which the Helmholtz equation is solved, the disadvantages of both methods are greatly diminished. Due to the DtN operators, light may be accurately fluxed into the
Gallezot, M.; Treyssède, F.; Laguerre, L.
2018-03-01
This paper investigates the computation of the forced response of elastic open waveguides with a numerical modal approach based on perfectly matched layers (PML). With a PML of infinite thickness, the solution can theoretically be expanded as a discrete sum of trapped modes, a discrete sum of leaky modes and a continuous sum of radiation modes related to the PML branch cuts. Yet with numerical methods (e.g. finite elements), the waveguide cross-section is discretized and the PML must be truncated to a finite thickness. This truncation transforms the continuous sum into a discrete set of PML modes. To guarantee the uniqueness of the numerical solution of the forced response problem, an orthogonality relationship is proposed. This relationship is applicable to any type of modes (trapped, leaky and PML modes) and hence allows the numerical solution to be expanded on a discrete sum in a convenient manner. This also leads to an expression for the modal excitability valid for leaky modes. The physical relevance of each type of mode for the solution is clarified through two numerical test cases, a homogeneous medium and a circular bar waveguide example, excited by a point source. The former is favourably compared to a transient analytical solution, showing that PML modes reassemble the bulk wave contribution in a homogeneous medium. The latter shows that the PML mode contribution yields the long-term diffraction phenomenon whereas the leaky mode contribution prevails closer to the source. The leaky mode contribution is shown to remain accurate even with a relatively small PML thickness, hence reducing the computational cost. This is of particular interest for solving three-dimensional waveguide problems, involving two-dimensional cross-sections of arbitrary shapes. Such a problem is handled in a third numerical example by considering a buried square bar.
Inhomogeneous generalizations of Bianchi type VIh models with perfect fluid
Roy, S. R.; Prasad, A.
1991-07-01
Inhomogeneous universes admitting an Abelian G2 of isometry and filled with perfect fluid have been derived. These contain as special cases exact homogeneous universes of Bianchi type VIh. Many of these universes asymptotically tend to homogeneous Bianchi VIh universes. The models have been discussed for their physical and kinematical behaviors.
Perfect posterior simulation for mixture and hidden Marko models
DEFF Research Database (Denmark)
Berthelsen, Kasper Klitgaard; Breyer, Laird A.; Roberts, Gareth O.
2010-01-01
In this paper we present an application of the read-once coupling from the past algorithm to problems in Bayesian inference for latent statistical models. We describe a method for perfect simulation from the posterior distribution of the unknown mixture weights in a mixture model. Our method...... is extended to a more general mixture problem, where unknown parameters exist for the mixture components, and to a hidden Markov model....
Ladm and Interlis as a Perfect Match for 3d Cadastre
Kalogianni, E.; Dimopoulou, E.; Quak, W.; Van Oosterom, P.
2017-10-01
Standardization in land administration domain has been expanded to 3D and even 4D representations, adopting a multipurpose character, in order to become the foundation of a sustainable and smart economic development. At the moment, although the potential benefits of 3D Cadastre is argued to be enormous and there are plenty of standards related to 3D Cadastre while others enhancing the role of 3D Cities, there is no complete solution for 3D Cadastre. That being so, the last years, there has been a rapid increase in the integration, harmonization and implementation support of such standards. In this context, the integration of 3D legal spaces with 3D physical objects is gaining ground, as the (invisible) legal boundaries do not always match with the physical counterparts, leading to obscure situations. LADM, the International Standard for land administration, was proved to be one of the best candidates to unambiguously represent 3D Rights, Restrictions and Responsibilities. On the other side, spatial data models and virtual city models manage 3D urban structures without focusing on legal aspects. Many researchers have explored integrations between those aspects giving promising results. In this direction, apart from international standards, also national standards have been developed to enable the communication between land information systems. One of the most representatives is INTERLIS, a Swiss standard, a precise, standardized Object Relational modelling language on the conceptual level, which allows for automated quality control. Thus, in this paper the focus is given on how INTERLIS and LADM complement each other in the actual implementation of land administration systems. Main challenges among others in the context of this research include: 1. extensible hierarchical and versioned code lists in INTERLIS models, 2. formally define LADM constraints in INTERLIS, 3. discuss 3D geometry types and 4. introduce a holistic LADM/INTERLIS approach for country profiles.
Role model and prototype matching
DEFF Research Database (Denmark)
Lykkegaard, Eva; Ulriksen, Lars
2016-01-01
Previous research has found that young people’s prototypes of science students and scientists affect their inclination to choose tertiary STEM programs (Science, Technology, Engineering and Mathematics). Consequently, many recruitment initiatives include role models to challenge these prototypes......’ meetings with the role models affected their thoughts concerning STEM students and attending university. The regular self-to-prototype matching process was shown in real-life role-models meetings to be extended to a more complex three-way matching process between students’ self-perceptions, prototype...... images and situation-specific conceptions of role models. Furthermore, the study underlined the positive effect of prolonged role-model contact, the importance of using several role models and that traditional school subjects catered more resistant prototype images than unfamiliar ones did...
DEFF Research Database (Denmark)
Shyroki, Dzmitry; Lavrinenko, Andrei
2007-01-01
A complex-coordinate method known under the guise of the perfectly matched layer (PML) method for treating unbounded domains in computational electrodynamics is related to similar techniques in fluid dynamics and classical quantum theory. It may also find use in electronic-structure finite......-difference simulations. Straightforward transfer of the PML formulation to other fields does not seem feasible, however, since it is a unique feature of electrodynamics - the natural invariance - that allows analytic trick of complex coordinate scaling to be represented as pure modification of local material parameters...
Directory of Open Access Journals (Sweden)
Eliza W. Beal
2016-01-01
Full Text Available There is a paucity of literature examining recipient-donor obesity matching on liver transplantation outcomes. The United Network for Organ Sharing database was queried for first-time recipients of liver transplant whose age was ≥18 between January 2003 and September 2013. Outcomes including patient and graft survival at 30 days, 1 year, and 5 years and overall, liver retransplantation, and length of stay were compared between nonobese recipients receiving a graft from nonobese donors and obese recipient-obese donor, obese recipient-nonobese donor, and nonobese recipient-obese donor pairs. 51,556 LT recipients were identified, including 34,217 (66% nonobese and 17,339 (34% obese recipients. The proportions of patients receiving an allograft from an obese donor were 24% and 29%, respectively, among nonobese and obese recipients. Graft loss (HR: 1.27; 95% CI: 1.09–1.46; p=0.002 and mortality (HR: 1.38; 95% CI: 1.16–1.65; p<0.001 at 30 days were increased in the obese recipient-obese donor pair. However, 1-year graft (HR: 0.83; 95% CI: 0.74–0.93; p=0.002 and patient (HR: 0.84; 95% CI: 0.74–0.95; p=0.007 survival and overall patient (HR: 0.93; 95% CI: 0.86–1.00; p=0.042 survival were favorable. There is evidence of recipient and donor obesity disadvantage early, but survival curves demonstrate improved long-term outcomes. It is important to consider obesity in the donor-recipient match.
Yee, Kwang Chien; Miils, Erin; Airey, Caroline
2008-01-01
The current healthcare delivery model will not meet future healthcare demands. The only sustainable healthcare future is one that best leverages advances in technology to improve productivity and efficiency. Information communication technology (ICT) has, therefore, been touted as the panacea of future healthcare challenges. Many ICT projects in healthcare, however, fail to deliver on their promises to transform the healthcare system. From a technologist's perspective, this is often due to the lack of socio-technical consideration. From a socio-cultural perspective, however, there is often strong inertia to change. While the utilisation of user-centred design principles will generate a new wave of enthusiasm among technologists, this has to be matched with socio-cultural changes within the healthcare system. Generation Y healthcare workers might be the socio-cultural factor required, in combination with new technology, to transform the healthcare system. Generation Y has generated significant technology-driven changes in many other industries. The socio-cultural understanding of generation Y healthcare workers is essential to guide the design and implementation of ICT solutions for a sustainable healthcare future. This paper presents the initial analysis of our qualitative study which aims to generate in-depth conceptual insights of generation Y healthcare workers and their view of ICT in healthcare. Our results show that generation Y healthcare workers might assist future ICT implementation in healthcare. This paper, however, argues that significant changes to the current healthcare organisation will be required in order to unleash the full potential of generation Y workers and ICT implementation. Finally, this paper presents some strategies to empower generation Y workers as change agents for a sustainable future healthcare system.
Polo-López, Lucas; Ruiz-Cruz, Jorge A.; Montejo-Garai, José R.; Rebollar, Jesús M.
2017-09-01
This contribution presents the analysis of waveguide problems involving general boundary conditions of perfect magnetic wall. This type of boundary condition is used in electromagnetic solvers very commonly when the device under analysis has physical symmetry, in order to speed up the computation time. This paper is focused on extending its use in problems having this type of boundary condition in the lateral and transverse walls of the waveguides involved in the problem. The presented formulation, based on the mode-matching method, will be applied to classical waveguide devices, but also to address radiating problems with a novel formulation. Different applications will be targeted, and the simulation results will be compared with those obtained by other numerical techniques (based on different solvers), validating the presented approach as another suitable tool for computer-aided design.
Directory of Open Access Journals (Sweden)
B. U. Musa
2017-04-01
Full Text Available The C++ programming language was used to implement three-dimensional (3-D finite-difference time-domain (FDTD technique to simulate radiation of high frequency electromagnetic waves in free space. To achieve any meaningful results the computational domain of interest should have to be truncated in some way and this is achieved by applying absorbing boundary conditions. A uniaxial perfectly matched layer (UPML absorbing boundary condition is used in this work. The discretised equations of the UPML in FDTD time stepping scheme were derived and has been successfully implemented using the computer program. Simulation results showed that the UPML behaves as an absorber. This was confirmed by comparing the results with another boundary condition, the Mur ABC.
Simulation of MILD combustion using Perfectly Stirred Reactor model
Chen, Z.
2016-07-06
A simple model based on a Perfectly Stirred Reactor (PSR) is proposed for moderate or intense low-oxygen dilution (MILD) combustion. The PSR calculation is performed covering the entire flammability range and the tabulated chemistry approach is used with a presumed joint probability density function (PDF). The jet, in hot and diluted coflow experimental set-up under MILD conditions, is simulated using this reactor model for two oxygen dilution levels. The computed results for mean temperature, major and minor species mass fractions are compared with the experimental data and simulation results obtained recently using a multi-environment transported PDF approach. Overall, a good agreement is observed at three different axial locations for these comparisons despite the over-predicted peak value of CO formation. This suggests that MILD combustion can be effectively modelled by the proposed PSR model with lower computational cost.
Yang, Jubiao; Yu, Feimi; Krane, Michael; Zhang, Lucy T
2018-01-01
In this work, a non-reflective boundary condition, the Perfectly Matched Layer (PML) technique, is adapted and implemented in a fluid-structure interaction numerical framework to demonstrate that proper boundary conditions are not only necessary to capture correct wave propagations in a flow field, but also its interacted solid behavior and responses. While most research on the topics of the non-reflective boundary conditions are focused on fluids, little effort has been done in a fluid-structure interaction setting. In this study, the effectiveness of the PML is closely examined in both pure fluid and fluid-structure interaction settings upon incorporating the PML algorithm in a fully-coupled fluid-structure interaction framework, the Immersed Finite Element Method. The performance of the PML boundary condition is evaluated and compared to reference solutions with a variety of benchmark test cases including known and expected solutions of aeroacoustic wave propagation as well as vortex shedding and advection. The application of the PML in numerical simulations of fluid-structure interaction is then investigated to demonstrate the efficacy and necessity of such boundary treatment in order to capture the correct solid deformation and flow field without the requirement of a significantly large computational domain.
Circuital model for the spherical geodesic waveguide perfect drain
International Nuclear Information System (INIS)
González, Juan C; Grabovičkić, Dejan; Benítez, Pablo; Miñano, Juan C
2012-01-01
The perfect drain for the Maxwell fish eye (MFE) is a non-magnetic dissipative region placed in the focal point to absorb all the incident radiation without reflection or scattering. The perfect drain was recently designed as a material with complex permittivity that depends on frequency. However, this material is only a theoretical material, so it cannot be used in practical devices. The perfect drain has been claimed as necessary for achieving super-resolution (Leonhardt 2009 New J. Phys. 11 093040), which has increased the interest in practical perfect drains suitable for manufacturing. Here, we present a practical perfect drain that is designed using a simple circuit (made of a resistance and a capacitor) connected to the coaxial line. Moreover, we analyze the super-resolution properties of a device equivalent to the MFE, known as a spherical geodesic waveguide, loaded with this perfect drain. The super-resolution analysis for this device is carried out using COMSOL Multiphysics. The results of simulations predict a super-resolution of up to λ/3000. (paper)
Parikh Matching in the Streaming Model
DEFF Research Database (Denmark)
Lee, Lap-Kei; Lewenstein, Moshe; Zhang, Qin
2012-01-01
|-length count vector. In the streaming model one seeks space-efficient algorithms for problems in which there is one pass over the data. We consider Parikh matching in the streaming model. To make this viable we search for substrings whose Parikh-mappings approximately match the input vector. In this paper we...... present upper and lower bounds on the problem of approximate Parikh matching in the streaming model....
Rao, V. U. M.; Vinutha, T.; Vijaya Shanthi, M.; Sree Devi Kumari, G.
2008-09-01
Exact Bianchi type-V cosmological models are presented in Einstein’s theory of gravitation with cosmological constant Λ in case of perfect fluid distribution. Also obtained Bianchi type-V cosmological models in a scalar-tensor theory of gravitation proposed by Saez and Ballester (1986) in case of perfect fluid distribution using and without using negative constant deceleration parameter. Some physical and geometrical properties of the models are also discussed.
Bianchi type-V cosmological models with perfect fluid and heat flow ...
Indian Academy of Sciences (India)
2015-11-27
-V cosmological models with perfect fluid and heat flow in Saez–Ballester theory. Shri Ram M ... Proceedings of the International Workshop/Conference on Computational Condensed Matter Physics and Materials Science
Exact EGB models for spherical static perfect fluids
Energy Technology Data Exchange (ETDEWEB)
Hansraj, Sudan; Chilambwe, Brian; Maharaj, Sunil D. [University of KwaZulu-Natal, Astrophysics and Cosmology Research Unit, School of Mathematics, Statistics and Computer Science, Private Bag 54001, Durban (South Africa)
2015-06-15
We obtain a new exact solution to the field equations for a 5-dimensional spherically symmetric static distribution in the Einstein-Gauss-Bonnet modified theory of gravity. By using a transformation, the study is reduced to the analysis of a single second order nonlinear differential equation. In general the condition of pressure isotropy produces a first order differential equation which is an Abel equation of the second kind. An exact solution is found. The solution is examined for physical admissibility. In particular a set of constants is found which ensures that a pressure-free hypersurface exists which defines the boundary of the distribution. Additionally the isotropic pressure and the energy density are shown to be positive within the radius of the sphere. The adiabatic sound-speed criterion is also satisfied within the fluid ensuring a subluminal sound speed. Furthermore, the weak, strong and dominant conditions hold throughout the distribution. On setting the Gauss-Bonnet coupling to zero, an exact solution for 5-dimensional perfect fluids in the standard Einstein theory is obtained. Plots of the dynamical quantities for the Gauss-Bonnet and the Einstein case reveal that the pressure is unaffected, while the energy density increases under the influence of the Gauss-Bonnet term. (orig.)
A hybrid of monopoly and perfect competition model for hi-tech products
Yang, P. C.; Wee, H. M.; Pai, S.; Yang, H. J.; Wee, P. K. P.
2010-11-01
For Hi-tech products, the demand rate, the component cost as well as the selling price usually decline significantly with time. In the case of perfect competition, shortages usually result in lost sales; while in a monopoly, shortages will be completely backordered. However, neither perfect competition nor monopoly exists. Therefore, there is a need to develop a replenishment model considering a hybrid of perfect competition and monopoly when the cost, price and demand are decreasing simultaneously. A numerical example and sensitivity analysis are carried out to illustrate this model. The results show that a higher decline-rate in the component cost leads to a smaller service level and a larger replenishment interval. When the component cost decline rate increases and the selling price decline rate decreases simultaneously, the replenishment interval decreases. In perfect competition it is better to have a high service level, while for the case with monopoly, keeping a low service level is better due to complete backordering.
History Matching: Towards Geologically Reasonable Models
DEFF Research Database (Denmark)
Melnikova, Yulia; Cordua, Knud Skou; Mosegaard, Klaus
that measures similarity between statistics of a training image and statistics of any smooth model is introduced and its analytical gradient is computed. This allows us to apply any gradientbased method to history matching problem and guide a solution until it satisfies both production data and complexity......This work focuses on the development of a new method for history matching problem that through a deterministic search finds a geologically feasible solution. Complex geology is taken into account evaluating multiple point statistics from earth model prototypes - training images. Further a function...
On a special case of model matching
Czech Academy of Sciences Publication Activity Database
Zagalak, Petr
2004-01-01
Roč. 77, č. 2 (2004), s. 164-172 ISSN 0020-7179 R&D Projects: GA ČR GA102/01/0608 Institutional research plan: CEZ:AV0Z1075907 Keywords : linear systems * state feedback * model matching Subject RIV: BC - Control Systems Theory Impact factor: 0.702, year: 2004
Effective high-order solver with thermally perfect gas model for hypersonic heating prediction
International Nuclear Information System (INIS)
Jiang, Zhenhua; Yan, Chao; Yu, Jian; Qu, Feng; Ma, Libin
2016-01-01
Highlights: • Design proper numerical flux for thermally perfect gas. • Line-implicit LUSGS enhances efficiency without extra memory consumption. • Develop unified framework for both second-order MUSCL and fifth-order WENO. • The designed gas model can be applied to much wider temperature range. - Abstract: Effective high-order solver based on the model of thermally perfect gas has been developed for hypersonic heat transfer computation. The technique of polynomial curve fit coupling to thermodynamics equation is suggested to establish the current model and particular attention has been paid to the design of proper numerical flux for thermally perfect gas. We present procedures that unify five-order WENO (Weighted Essentially Non-Oscillatory) scheme in the existing second-order finite volume framework and a line-implicit method that improves the computational efficiency without increasing memory consumption. A variety of hypersonic viscous flows are performed to examine the capability of the resulted high order thermally perfect gas solver. Numerical results demonstrate its superior performance compared to low-order calorically perfect gas method and indicate its potential application to hypersonic heating predictions for real-life problem.
Brane world models with bulk perfect fluid and broken 4D Poincaré invariance
Akarsu, Özgür; Chopovsky, Alexey; Eingorn, Maxim; Fakhr, Seyed Hossein; Zhuk, Alexander
2018-02-01
We consider 5D brane world models with broken global 4D Poincaré invariance (4D part of the spacetime metric is not conformal to the Minkowski spacetime). The bulk is filled with the negative cosmological constant and may contain a perfect fluid. In the case of empty bulk (the perfect fluid is absent), it is shown that one brane solution always has either a physical or a coordinate singularity in the bulk. We cut off these singularities in the case of compact two brane model and obtain regular exact solutions for both 4D Poincaré broken and restored invariance. When the perfect fluid is present in the bulk, we get the master equation for the metric coefficients in the case of arbitrary bulk perfect fluid equation of state (EoS) parameters. In two particular cases of EoS, we obtain the analytic solutions for thin and thick branes. First one generalizes the well known Randall-Sundrum model with one brane to the case of the bulk anisotropic perfect fluid. In the second solution, the 4D Poincaré invariance is restored. Here, the spacetime goes asymptotically to the anti-de Sitter one far from the thick brane.
CERN. Geneva
2014-01-01
IBM Software Defined Storage, in particular the technology offering codenamed Elastic Storage (based on GPFS technology) has proven to be an ideal match for Enterprise File Sync and Share (EFSS) solutions that need highly scalable storage. The presentation will provide insight into the integration of Elastic Storage with the ownCloud Enterprise Edition (based on Open Source technology) software that showed impressive scalability and performance metrics during a proof-of-concept phase of an installation that is supposed to serve 300000 users when fully deployed.
Perfect fluid Bianchi Type-I cosmological models with time varying G ...
Indian Academy of Sciences (India)
Bianchi Type-I cosmological models containing perfect fluid with time varying and have been presented. The solutions obtained represent an expansion scalar bearing a constant ratio to the anisotropy in the direction of space-like unit vector . Of the two models obtained, one has negative vacuum energy density, ...
Perfect fluid Bianchi Type-I cosmological models with time varying G ...
Indian Academy of Sciences (India)
Abstract. Bianchi Type-I cosmological models containing perfect fluid with time vary- ing G and Λ have been presented. The solutions obtained represent an expansion scalar θ bearing a constant ratio to the anisotropy in the direction of space-like unit vector λi. Of the two models obtained, one has negative vacuum energy ...
Bianchi type-V cosmological models with perfect fluid and heat flow ...
Indian Academy of Sciences (India)
physics pp. 415–427. Bianchi type-V cosmological models with perfect fluid and heat flow in Saez–Ballester theory. SHRI RAM1, M ZEYAUDDIN1 and C P SINGH2,∗ ... Introduction. In the last few decades there has been much interest in alternative theories of gravitation, especially the scalar–tensor theories proposed by ...
Bianchi Type-V model with a perfect fluid and Λ-term
Indian Academy of Sciences (India)
type; perfect fluid; lambda term. PACS Nos 04.20.jb; 98.80.Hw. 1. Introduction. In view of its importance in explaining the observational cosmology, many workers have considered cosmological models with dark energy. In a recent paper, Kremer.
Bianchi type-V cosmological models with perfect fluid and heat flow ...
Indian Academy of Sciences (India)
415–427. Bianchi type-V cosmological models with perfect fluid and heat flow in Saez–Ballester theory. SHRI RAM1, M ZEYAUDDIN1 and C P SINGH2,∗. 1Department of Applied Mathematics, Institute of Technology, Banaras Hindu University,. Varanasi 221 005, India. 2Department of Applied Mathematics, Delhi College ...
Rao, V. U. M.; Jayasudha, L.
2015-07-01
Five dimensional spherically symmetric space-time is considered in the presence of perfect fluid source in the scalar-tensor theory of gravitation proposed by Saez and Ballester (Phys. Lett. A 113:467, 1986). An exact solution of the field equations is obtained using a relation between the metric potentials which represents a stiff fluid model in this theory. Some physical properties of the model are also discussed.
A Perfect Price Discrimination Market Model with Production, and a (Rational) Convex Program for It
Goel, Gagan; Vazirani, Vijay
Recent results showed PPAD-completeness of the problem of computing an equilibrium for Fisher's market model under additively separable, piecewise-linear, concave utilities. We show that introducing perfect price discrimination in this model renders its equilibrium polynomial time computable. Moreover, its set of equilibria are captured by a convex program that generalizes the classical Eisenberg-Gale program, and always admits a rational solution.
Recurrent network models for perfect temporal integration of fluctuating correlated inputs.
Directory of Open Access Journals (Sweden)
Hiroshi Okamoto
2009-06-01
Full Text Available Temporal integration of input is essential to the accumulation of information in various cognitive and behavioral processes, and gradually increasing neuronal activity, typically occurring within a range of seconds, is considered to reflect such computation by the brain. Some psychological evidence suggests that temporal integration by the brain is nearly perfect, that is, the integration is non-leaky, and the output of a neural integrator is accurately proportional to the strength of input. Neural mechanisms of perfect temporal integration, however, remain largely unknown. Here, we propose a recurrent network model of cortical neurons that perfectly integrates partially correlated, irregular input spike trains. We demonstrate that the rate of this temporal integration changes proportionately to the probability of spike coincidences in synaptic inputs. We analytically prove that this highly accurate integration of synaptic inputs emerges from integration of the variance of the fluctuating synaptic inputs, when their mean component is kept constant. Highly irregular neuronal firing and spike coincidences are the major features of cortical activity, but they have been separately addressed so far. Our results suggest that the efficient protocol of information integration by cortical networks essentially requires both features and hence is heterotic.
Pradhan, Anirudh; Singh, P. K.; Yadav, A. K.
2007-01-01
A plane-symmetric inhomogeneous cosmological model of perfect fluid distribution with electro-magnetic field is obtained. The source of the magnetic field is due to an electric current produced along the z-axis. $F_{12}$ is the non-vanishing component of electromagnetic field tensor. To get a deterministic solution, we assume the free gravitational field is Petrov type-II non-degenerate. The behaviour of the electro-magnetic field tensor together with some physical aspects of the model are al...
Vaz, A.; Paris, C. B.; Olascoaga, M. J.; Kourafalou, V.; Kang, H.
2016-02-01
Mesophotic reefs have been hypothesized to act as a refugia, by exporting larvae to more vulnerable shallow water reefs and potentially aiding the replenishment of disturbed populations. Despite the fundamental role of mesophotic reef for the recovery and conservation of shallow water reef ecosystems, the spatio-temporal extent of such connections is currently unresolved. Here we aim to explore the underlaying mechanisms of the connections between a mesophotic reef, the Pulley Ridge, and the shallow water Florida Keys reefs, by simulating the dispersal of the bicolor damselfish, Stegastes partitus. We use the Connectivity Modeling System (CMS) of the University of Miami, an open-source individual-based model, and present new biophysical modeling code to allow a realistic representation of 3-dimensional discreet coral reef habitats and investigate vertical connectivity. Virtual larvae are released and tracked within a fine resolution ( 900m) hydrodynamic model until their settlement. S. partitus biological traits such as spawning periodicity, mortality and vertical migration are also incorporated on the model. Probabilistic simulations indicate mesophotic-shallow connections, with larvae spawned at Pulley Ridge reaching the Florida Keys settlement grounds during sporadic settlement pulses. These "perfect storm" settlement events are modulated by the co-occurence of larval traits with physical processes, particularly by the interaction of ontogenetic vertical migration and the Florida Current fronts and cyclonic eddies. This demonstrates that mesophotic coral reef ecosystems can also serve as a refugia for coral reef fish and suggests that they could increase the resilience of their shallow counterpart.
Can simple population genetic models reconcile partial match ...
Indian Academy of Sciences (India)
A recent study of partial matches in the Arizona offender database of DNA profiles has revealed a large number of nine and ten locus matches. I use simple models that incorporate the product rule, population substructure, and relatedness to predict the expected number of matches in large databases. I find that there is a ...
FOI-PERFECT code: 3D relaxation MHD modeling and Applications
Wang, Gang-Hua; Duan, Shu-Chao; Comutational Physics Team Team
2016-10-01
One of the challenges in numerical simulations of electromagnetically driven high energy density (HED) systems is the existence of vacuum region. FOI-PERFECT code adopts a full relaxation magnetohydrodynamic (MHD) model. The electromagnetic part of the conventional model adopts the magnetic diffusion approximation. The vacuum region is approximated by artificially increasing the resistivity. On one hand the phase/group velocity is superluminal and hence non-physical in the vacuum region, on the other hand a diffusion equation with large diffusion coefficient can only be solved by implicit scheme which is difficult to be parallelized and converge. A better alternative is to solve the full electromagnetic equations. Maxwell's equations coupled with the constitutive equation, generalized Ohm's law, constitute a relaxation model. The dispersion relation is given to show its transition from electromagnetic propagation in vacuum to resistive MHD in plasma in a natural way. The phase and group velocities are finite for this system. A better time stepping is adopted to give a 3rd full order convergence in time domain without the stiff relaxation term restriction. Therefore it is convenient for explicit & parallel computations. Some numerical results of FOI-PERFECT code are also given. Project supported by the National Natural Science Foundation of China (Grant No. 11571293) And Foundation of China Academy of Engineering Physics (Grant No. 2015B0201023).
Complementary responses to mean and variance modulations in the perfect integrate-and-fire model.
Pressley, Joanna; Troyer, Todd W
2009-07-01
In the perfect integrate-and-fire model (PIF), the membrane voltage is proportional to the integral of the input current since the time of the previous spike. It has been shown that the firing rate within a noise free ensemble of PIF neurons responds instantaneously to dynamic changes in the input current, whereas in the presence of white noise, model neurons preferentially pass low frequency modulations of the mean current. Here, we prove that when the input variance is perturbed while holding the mean current constant, the PIF responds preferentially to high frequency modulations. Moreover, the linear filters for mean and variance modulations are complementary, adding exactly to one. Since changes in the rate of Poisson distributed inputs lead to proportional changes in the mean and variance, these results imply that an ensemble of PIF neurons transmits a perfect replica of the time-varying input rate for Poisson distributed input. A more general argument shows that this property holds for any signal leading to proportional changes in the mean and variance of the input current.
Energy Technology Data Exchange (ETDEWEB)
Fauqueux, S.
2003-02-01
We consider the propagation of elastic waves in unbounded domains. A new formulation of the linear elasticity system as an H (div) - L{sup 2} system enables us to use the 'mixed spectral finite element method', This new method is based on the definition of new spaces of approximation and the use of mass-lumping. It leads to an explicit scheme with reduced storage and provides the same solution as the spectral finite element method. Then, we model unbounded domains by using Perfectly Matched Layers. Instabilities in the PML in the case of particular 2D elastic media are pointed out and investigated. The numerical method is validated and tested in the case of acoustic and elastic realistic models. A plane wave analysis gives results about numerical dispersion and shows that meshes adapted to the physical and geometrical properties of the media are more accurate than the others. Then, an extension of the method to fluid-solid coupling is introduced for 2D seismic propagation. (author)
Directory of Open Access Journals (Sweden)
Kaihong Wang
2014-01-01
Full Text Available This paper studies channel consisting of a manufacturer and two retailers. As a basis for comparison, the first, multiagent Stackelberg model has been structured based on perfect rationality. Further, fairness preference theory will be embedded in marketing channel multiagent Stackelberg model, and the results show that if the retailers have a jealous fairness preference, the manufacturer will reduce the wholesale price, retailers will increase the effort level, product sales will be increased, and the total channel utility and manufacturers’ utility will be pareto improvement, but the pareto improvement of retailers’ utility is associated with the interval of jealousy fairness preference coefficient. If the retailers have a sympathetic fairness preference, the manufacturer increases wholesale price, retailers reduce the effort level, and the total channel utility, manufacturer’s utility, and retailers’ utility are less than that of the no fairness preference utility.
DEFF Research Database (Denmark)
Polat, Burak; Meincke, Peter
2004-01-01
A forward model for ground penetrating radar imaging of buried 3-D perfect electric conductors is addressed within the framework of diffraction tomography. The similarity of the present forward model derived within the physical optics approximation with that derived within the first Born approxim......A forward model for ground penetrating radar imaging of buried 3-D perfect electric conductors is addressed within the framework of diffraction tomography. The similarity of the present forward model derived within the physical optics approximation with that derived within the first Born...
Rao, V. U. M.; Vijaya Santhi, M.; Vinutha, T.
2008-09-01
Exact Bianchi type-II, VIII and IX cosmological models are obtained in a scalar tensor theory proposed by Saez and Ballester (Phys. Lett. A 113:467, 1986) with perfect fluid as a source. Some physical and geometrical properties of the models are studied. It is observed that the models are free from initial singularities and they are expanding with time.
International Nuclear Information System (INIS)
Massoud, J.P.; Bugat, St.; Marini, B.; Lidbury, D.; Van Dyck, St.; Debarberis, L.
2008-01-01
Full text of publication follows. In nuclear PWRs, materials undergo degradation due to severe irradiation conditions that may limit their operational life. Utilities operating these reactors must quantify the aging and the potential degradations of reactor pressure vessels and also of internal structures to ensure safe and reliable plant operation. The EURATOM 6. Framework Integrated Project PERFECT (Prediction of Irradiation Damage Effects in Reactor Components) addresses irradiation damage in RPV materials and components by multi-scale modelling. This state-of-the-art approach offers potential advantages over the conventional empirical methods used in current practice of nuclear plant lifetime management. Launched in January 2004, this 48-month project is focusing on two main components of nuclear power plants which are subject to irradiation damage: the ferritic steel reactor pressure vessel and the austenitic steel internals. This project is also an opportunity to integrate the fragmented research and experience that currently exists within Europe in the field of numerical simulation of radiation damage and creates the links with international organisations involved in similar projects throughout the world. Continuous progress in the physical understanding of the phenomena involved in irradiation damage and continuous progress in computer sciences make possible the development of multi-scale numerical tools able to simulate the effects of irradiation on materials microstructure. The consequences of irradiation on mechanical and corrosion properties of materials are also tentatively modelled using such multi-scale modelling. But it requires to develop different mechanistic models at different levels of physics and engineering and to extend the state of knowledge in several scientific fields. And the links between these different kinds of models are particularly delicate to deal with and need specific works. Practically the main objective of PERFECT is to build
Bianchi Type-V model with a perfect fluid and Λ-term
Indian Academy of Sciences (India)
Abstract. A self-consistent system of gravitational field with a binary mixture of perfect fluid and dark energy given by a cosmological constant has been considered in Bianchi. Type-V universe. The perfect fluid is chosen to be obeying either the equation of state p = γρ with γ ∈ [0, 1] or a van der Waals equation of state.
Bianchi Type-V model with a perfect fluid and Λ-term
Indian Academy of Sciences (India)
A self-consistent system of gravitational field with a binary mixture of perfect fluid and dark energy given by a cosmological constant has been considered in Bianchi Type-V universe. The perfect fluid is chosen to be obeying either the equation of state = ρ with ∈ [0, 1] or a van der Waals equation of state. The role of ...
Model Reduction by Moment Matching for Linear Switched Systems
DEFF Research Database (Denmark)
Bastug, Mert; Petreczky, Mihaly; Wisniewski, Rafal
2014-01-01
A moment-matching method for the model reduction of linear switched systems (LSSs) is developed. The method is based based upon a partial realization theory of LSSs and it is similar to the Krylov subspace methods used for moment matching for linear systems. The results are illustrated by numerical...
Money creation in a random matching model
Alexei Deviatov
2004-01-01
I study money creation in versions of the Trejos-Wright (1995) and Shi (1995) models with indivisible money and individual holdings bounded at two units. I work with the same class of policies as in Deviatov and Wallace (2001), who study money creation in that model. However, I consider an alternative notion of implementability–the ex ante pairwise core. I compute a set of numerical examples to determine whether money creation is beneficial. I find beneficial e?ects of money creation if indiv...
Lorentz invariant noncommutative algebra for cosmological models coupled to a perfect fluid
Energy Technology Data Exchange (ETDEWEB)
Abreu, Everton M.C.; Marcial, Mateus V.; Mendes, Albert C.R.; Oliveira, Wilson [Universidade Federal Rural do Rio de Janeiro (UFRRJ), Seropedica, RJ (Brazil); Universidade Federal de Juiz de Fora, MG (Brazil)
2013-07-01
Full text: In current theoretical physics there is a relevant number of theoretical investigations that lead to believe that at the first moments of our Universe, the geometry was not commutative and the dominating physics at that time was ruled by the laws of noncommutative (NC) geometry. Therefore, the idea is that the physics of the early moments can be constructed based on these concepts. The first published work using the idea of a NC spacetime were carried out by Snyder who believed that NC principles could make the quantum field theory infinities disappear. However, it did not occur and Snyder's ideas were put to sleep for a long time. The main modern motivations that rekindle the investigation about NC field theories came from string theory and quantum gravity. In the context of quantum mechanics for example, R. Banerjee discussed how NC structures appear in planar quantum mechanics providing a useful way for obtaining them. The analysis was based on the NC algebra used in planar quantum mechanics that was originated from 't Hooft's analysis on dissipation and quantization. In this work we carry out a NC algebra analysis of the Friedmann-Robert-Walker model, coupled to a perfect fluid and in the presence of a cosmological constant. The classical field equations are modified, by the introduction of a shift operator, in order to introduce noncommutativity in these models. (author)
International Nuclear Information System (INIS)
Gaikwad, N. P.; Borkar, M. S.; Charjan, S. S.
2011-01-01
We investigate the Bianchi type-I massive string magnetized barotropic perfect fluid cosmological model in Rosen's bimetric theory of gravitation with and without a magnetic field by applying the techniques used by Latelier (1979, 1980) and Stachel (1983). To obtain a deterministic model of the universe, it is assumed that the universe is filled with barotropic perfect fluid distribution. The physical and geometrical significance of the model are discussed. By comparing our model with the model of Bali et al. (2007), it is realized that there are no big-bang and big-crunch singularities in our model and T = 0 is not the time of the big bang, whereas the model of Bali et al. starts with a big bang at T = 0. Further, our model is in agreement with Bali et al. (2007) as time increases in the presence, as well as in the absence, of a magnetic field. (geophysics, astronomy, and astrophysics)
A fast-simplified wheel-rail contact model consistent with perfect plastic materials
Sebès, Michel; Chevalier, Luc; Ayasse, Jean-Bernard; Chollet, Hugues
2012-09-01
A method is described which is an extension of rolling contact models with respect to plasticity. This new method, which is an extension of the STRIPES semi-Hertzian (SH) model, has been implemented in a multi-body-system (MBS) package and does not result in a longer execution time than the STRIPES SH model [J.B. Ayasse and H. Chollet, Determination of the wheel-rail contact patch in semi-Hertzian conditions, Veh. Syst. Dyn. 43(3) (2005), pp. 161-172]. High speed of computation is obtained by some hypotheses about the plastic law, the shape of stresses, the locus of the maximum stress and the slip. Plasticity does not change the vehicle behaviour but there is a need for an extension of rolling contact models with respect to plasticity as far as fatigue analysis of rail is concerned: rolling contact fatigue may be addressed via the finite element method (FEM) including material non-linearities, where loads are the contact stresses provided by the post-processing of MBS results [K. Dang Van, M.H. Maitournam, Z. Moumni, and F. Roger, A comprehensive approach for modeling fatigue and fracture of rails, Eng. Fract. Mech. 76 (2009), pp. 2626-2636]. In STRIPES, like in other MBS models, contact stresses may exceed the plastic yield criterion, leading to wrong results in the subsequent FEM analysis. With the proposed method, contact stresses are kept consistent with a perfect plastic law, avoiding these problems. The method is benchmarked versus non-linear FEM in Hertzian geometries. As a consequence of taking plasticity into account, contact patch area is bigger than the elastic one. In accordance with FEM results, a different ellipse aspect ratio than the one predicted by Hertz theory was also found and finally pressure does not exceed the threshold prescribed by the plastic law. The method also provides more exact results with non-Hertzian geometries. The new approach is finally compared with non-linear FEM in a tangent case with a unidirectional load and a complete
"Living in sin" and marriage : a matching model
Rao Sahib, P. Padma; Gu, X. Xinhua
1999-01-01
This paper develops a two sided matching model of premarital cohabitation and marriage in which premarital cohabitation serves as a period of learning. We solve for the optimal policy to be followed by individuals by treating the model as a three stage dynamic programming problem. We find that
Monahan, Patrick O.; Ankenmann, Robert D.
2010-01-01
When the matching score is either less than perfectly reliable or not a sufficient statistic for determining latent proficiency in data conforming to item response theory (IRT) models, Type I error (TIE) inflation may occur for the Mantel-Haenszel (MH) procedure or any differential item functioning (DIF) procedure that matches on summed-item…
DEFF Research Database (Denmark)
Pless, Mette; Sørensen, Niels Ulrik
towards a performance-culture, where it is through performing (perfectly), that one becomes acknowledged as a young person, and where top-performances and the ability to position oneself as a ’winner’ is accentuated in young people’s narratives (Sørensen et al 2013, Jackson 2006). In the paper we ask how...... – and to what extent – performance-culture, and following from this, the narrow concept of normality, is something that different young people relate and define themselves in relation to. At the same time we maintain a focus on how common social demands and structurations affect and are managed by different...
International Nuclear Information System (INIS)
Gol'dshtejn, M.I.; Popov, V.V.; Cheremnykh, V.G.
1980-01-01
Using the Fe-Nb-V-C-N and Fe-Ti-V-C-N systems' low carbon steels, the earlier suggested model of perfect solid solutions has been experimentally researched. Also studied has been the feasibility to calculate the composition of carbonitrides in steels by the derived equations, that comprise, as parameters, products of respective compounds' solubility and coefficients of components interaction in iron-based solid solutions. A conclusion is drawn that perfect solutions models may be used adequately for complex carbonitrides like Nbsub(p)Vsub(1-p)Csub(q)Nsub(1-q) and Tisub(p)Vsub(1-p)Csub(q)Nsub(1-q) during the calculations of their equilibrium composition and solubility in steels
Equilibrium Price Dispersion in a Matching Model with Divisible Money
Kamiya, K.; Sato, T.
2002-01-01
The main purpose of this paper is to show that, for any given parameter values, an equilibrium with dispersed prices (two-price equilibrium) exists in a simple matching model with divisible money presented by Green and Zhou (1998).We also show that our two-price equilibrium is unique in certain
Czech Academy of Sciences Publication Activity Database
Roubíček, Tomáš; Valdman, Jan
2016-01-01
Roč. 76, č. 1 (2016), s. 314-340 ISSN 0036-1399 R&D Projects: GA ČR GA13-18652S; GA ČR GA14-15264S Institutional support: RVO:67985556 ; RVO:61388998 Keywords : Prandtl-Reuss perfect plasticity * bounded-deformation space * incomplete damage Subject RIV: BA - General Mathematics Impact factor: 1.670, year: 2016 http://library.utia.cas.cz/separaty/2016/MTR/valdman-0458557.pdf
Fsheikh, Ahmed H.
2013-01-01
A nonlinear orthogonal matching pursuit (NOMP) for sparse calibration of reservoir models is presented. Sparse calibration is a challenging problem as the unknowns are both the non-zero components of the solution and their associated weights. NOMP is a greedy algorithm that discovers at each iteration the most correlated components of the basis functions with the residual. The discovered basis (aka support) is augmented across the nonlinear iterations. Once the basis functions are selected from the dictionary, the solution is obtained by applying Tikhonov regularization. The proposed algorithm relies on approximate gradient estimation using an iterative stochastic ensemble method (ISEM). ISEM utilizes an ensemble of directional derivatives to efficiently approximate gradients. In the current study, the search space is parameterized using an overcomplete dictionary of basis functions built using the K-SVD algorithm.
Estimating a marriage matching model with spillover effects.
Choo, Eugene; Siow, Aloysius
2006-08-01
We use marriage matching functions to study how marital patterns change when population supplies change. Specifically, we use a behavioral marriage matching function with spillover effects to rationalize marriage and cohabitation behavior in contemporary Canada. The model can estimate a couple's systematic gains to marriage and cohabitation relative to remaining single. These gains are invariant to changes in population supplies. Instead, changes in population supplies redistribute these gains between a couple. Although the model is behavioral, it is nonparametric. It can fit any observed cross-sectional marriage matching distribution. We use the estimated model to quantify the impacts of gender differences in mortality rates and the baby boom on observed marital behavior in Canada. The higher mortality rate of men makes men scarcer than women. We show that the scarceness of men modestly reduced the welfare of women and increased the welfare of men in the marriage market. On the other hand, the baby boom increased older men's net gains to entering the marriage market and lowered middle-aged women's net gains.
National Research Council Canada - National Science Library
Keller, Martin G
1999-01-01
In the fields of computational vision and image understanding, the object recognition problem can be formulated as a problem of matching a collection of model features to features extracted from an observed scene...
Time reversal mirror and perfect inverse filter in a microscopic model for sound propagation
Calvo, Hernán L.; Danieli, Ernesto P.; Pastawski, Horacio M.
2007-09-01
Time reversal of quantum dynamics can be achieved by a global change of the Hamiltonian sign (a hasty Loschmidt daemon), as in the Loschmidt Echo experiments in NMR, or by a local but persistent procedure (a stubborn daemon) as in the time reversal mirror (TRM) used in ultrasound acoustics. While the first is limited by chaos and disorder, the last procedure seems to benefit from it. As a first step to quantify such stability we develop a procedure, the perfect inverse filter (PIF), that accounts for memory effects, and we apply it to a system of coupled oscillators. In order to ensure a numerical many-body dynamics intrinsically reversible, we develop an algorithm, the pair partitioning, based on the Trotter strategy used for quantum dynamics. We analyze situations where the PIF gives substantial improvements over the TRM.
Elevated Temperature Primary Load Design Method Using Pseudo Elastic-Perfectly Plastic Model
Energy Technology Data Exchange (ETDEWEB)
Carter, Peter [Stress Engineering Services Inc.; Sham, Sam [ORNL; Jetter, Robert I [Consultant
2012-01-01
A new primary load design method for elevated temperature service has been developed. Codification of the procedure in an ASME Boiler and Pressure Vessel Code, Section III Code Case is being pursued. The proposed primary load design method is intended to provide the same margins on creep rupture, yielding and creep deformation for a component or structure that are implicit in the allowable stress data. It provides a methodology that does not require stress classification and is also applicable to a full range of temperature above and below the creep regime. Use of elastic-perfectly plastic analysis based on allowable stress with corrections for constraint, steady state stress and creep ductility is described. This approach is intended to ensure that traditional primary stresses are the basis for design, taking into account ductility limits to stress re-distribution and multiaxial rupture criteria.
Directory of Open Access Journals (Sweden)
Cătălin Dima
2010-06-01
Full Text Available We present a variant of ATL with distributed knowledge operators based on a synchronous and perfect recall semantics. The coalition modalities in this logic are based on partial observation of the full history, and incorporate a form of cooperation between members of the coalition in which agents issue their actions based on the distributed knowledge, for that coalition, of the system history. We show that model-checking is decidable for this logic. The technique utilizes two variants of games with imperfect information and partially observable objectives, as well as a subset construction for identifying states whose histories are indistinguishable to the considered coalition.
Directory of Open Access Journals (Sweden)
Takahiro eDoi
2014-10-01
Full Text Available Three-dimensional visual perception requires correct matching of images projected to the left and right eyes. The matching process is faced with an ambiguity: part of one eye’s image can be matched to multiple parts of the other eye’s image. This stereo correspondence problem is complicated for random-dot stereograms (RDSs, because dots with an identical appearance produce numerous potential matches. Despite such complexity, human subjects can perceive a coherent depth structure. A coherent solution to the correspondence problem does not exist for anticorrelated RDSs (aRDSs, in which luminance contrast is reversed in one eye. Neurons in the visual cortex reduce disparity selectivity for aRDSs progressively along the visual processing hierarchy. A disparity-energy model followed by threshold nonlinearity (threshold energy model can account for this reduction, providing a possible mechanism for the neural matching process. However, the essential computation underlying the threshold energy model is not clear. Here, we propose that a nonlinear modification of cross-correlation, which we term ‘cross-matching’, represents the essence of the threshold energy model. We placed half-wave rectification within the cross-correlation of the left-eye and right-eye images. The disparity tuning derived from cross-matching was attenuated for aRDSs. We simulated a psychometric curve as a function of graded anticorrelation (graded mixture of aRDS and normal RDS; this simulated curve reproduced the match-based psychometric function observed in human near/far discrimination. The dot density was 25% for both simulation and observation. We predicted that as the dot density increased, the performance for aRDSs should decrease below chance (i.e., reversed depth, and the level of anticorrelation that nullifies depth perception should also decrease. We suggest that cross-matching serves as a simple computation underlying the match-based disparity signals in
MODELING CONTROLLED ASYNCHRONOUS ELECTRIC DRIVES WITH MATCHING REDUCERS AND TRANSFORMERS
Directory of Open Access Journals (Sweden)
V. S. Petrushin
2015-04-01
Full Text Available Purpose. Working out of mathematical models of the speed-controlled induction electric drives ensuring joint consideration of transformers, motors and loadings, and also matching reducers and transformers, both in static, and in dynamic regimes for the analysis of their operating characteristics. Methodology. At mathematical modelling are considered functional, mass, dimensional and cost indexes of reducers and transformers that allows observing engineering and economic aspects of speed-controlled induction electric drives. The mathematical models used for examination of the transitive electromagnetic and electromechanical processes, are grounded on systems of nonlinear differential equations with nonlinear coefficients (parameters of equivalent circuits of motors, varying in each operating point, including owing to appearances of saturation of magnetic system and current displacement in a winding of a rotor of an induction motor. For the purpose of raise of level of adequacy of models a magnetic circuit iron, additional and mechanical losses are considered. Results. Modelling of the several speed-controlled induction electric drives, different by components, but working on a loading equal on character, magnitude and a demanded control range is executed. At use of characteristic families including mechanical, at various parameters of regulating on which performances of the load mechanism are superimposed, the adjusting characteristics representing dependences of a modification of electrical, energy and thermal magnitudes from an angular speed of motors are gained. Originality. The offered complex models of speed-controlled induction electric drives with matching reducers and transformers, give the chance to realize well-founded sampling of components of drives. They also can be used as the design models by working out of speed-controlled induction motors. Practical value. Operating characteristics of various speed-controlled induction electric
Edery, Ariel; Graham, Noah; MacDonald, Ilana
2009-06-01
Under dimensional reduction, a system in D spacetime dimensions will not necessarily yield its D-1-dimensional analog version. Among other things, this result will depend on the boundary conditions and the dimension D of the system. We investigate this question for scalar and Abelian gauge fields under boundary conditions that obey the symmetries of the action. We apply our findings to the Casimir piston, an ideal system for detecting boundary effects. Our investigation is not limited to extra dimensions and we show that the original piston scenario proposed in 2004, a toy model involving a scalar field in 3D (2+1) dimensions, can be obtained via dimensional reduction from a more realistic 4D electromagnetic (EM) system. We show that for perfect conductor conditions, a D-dimensional EM field reduces to a D-1 scalar field and not its lower-dimensional version. For Dirichlet boundary conditions, no theory is recovered under dimensional reduction and the Casimir pressure goes to zero in any dimension. This “zero Dirichlet” result is useful for understanding the EM case. We then identify two special systems where the lower-dimensional version is recovered in any dimension: systems with perfect magnetic conductor (PMC) and Neumann boundary conditions. We show that these two boundary conditions can be obtained from a variational procedure in which the action vanishes outside the bounded region. The fields are free to vary on the surface and have zero modes, which survive after dimensional reduction.
Using visual analytics model for pattern matching in surveillance data
Habibi, Mohammad S.
2013-03-01
In a persistent surveillance system huge amount of data is collected continuously and significant details are labeled for future references. In this paper a method to summarize video data as a result of identifying events based on these tagged information is explained, leading to concise description of behavior within a section of extended recordings. An efficient retrieval of various events thus becomes the foundation for determining a pattern in surveillance system observations, both in its extended and fragmented versions. The patterns consisting of spatiotemporal semantic contents are extracted and classified by application of video data mining on generated ontology, and can be matched based on analysts interest and rules set forth for decision making. The proposed extraction and classification method used in this paper uses query by example for retrieving similar events containing relevant features, and is carried out by data aggregation. Since structured data forms majority of surveillance information this Visual Analytics model employs KD-Tree approach to group patterns in variant space and time, thus making it convenient to identify and match any abnormal burst of pattern detected in a surveillance video. Several experimental video were presented to viewers to analyze independently and were compared with the results obtained in this paper to demonstrate the efficiency and effectiveness of the proposed technique.
Multimodal correlation and intraoperative matching of virtual models in neurosurgery
Ceresole, Enrico; Dalsasso, Michele; Rossi, Aldo
1994-01-01
The multimodal correlation between different diagnostic exams, the intraoperative calibration of pointing tools and the correlation of the patient's virtual models with the patient himself, are some examples, taken from the biomedical field, of a unique problem: determine the relationship linking representation of the same object in different reference frames. Several methods have been developed in order to determine this relationship, among them, the surface matching method is one that gives the patient minimum discomfort and the errors occurring are compatible with the required precision. The surface matching method has been successfully applied to the multimodal correlation of diagnostic exams such as CT, MR, PET and SPECT. Algorithms for automatic segmentation of diagnostic images have been developed to extract the reference surfaces from the diagnostic exams, whereas the surface of the patient's skull has been monitored, in our approach, by means of a laser sensor mounted on the end effector of an industrial robot. An integrated system for virtual planning and real time execution of surgical procedures has been realized.
Mouse models for gastric cancer: Matching models to biological questions.
Poh, Ashleigh R; O'Donoghue, Robert J J; Ernst, Matthias; Putoczki, Tracy L
2016-07-01
Gastric cancer is the third leading cause of cancer-related mortality worldwide. This is in part due to the asymptomatic nature of the disease, which often results in late-stage diagnosis, at which point there are limited treatment options. Even when treated successfully, gastric cancer patients have a high risk of tumor recurrence and acquired drug resistance. It is vital to gain a better understanding of the molecular mechanisms underlying gastric cancer pathogenesis to facilitate the design of new-targeted therapies that may improve patient survival. A number of chemically and genetically engineered mouse models of gastric cancer have provided significant insight into the contribution of genetic and environmental factors to disease onset and progression. This review outlines the strengths and limitations of current mouse models of gastric cancer and their relevance to the pre-clinical development of new therapeutics. © 2016 The Authors Journal of Gastroenterology and Hepatology published by Journal of Gastroenterology and Hepatology Foundation and John Wiley & Sons Australia, Ltd.
Unconditional or Conditional Logistic Regression Model for Age-Matched Case-Control Data?
Kuo, Chia-Ling; Duan, Yinghui; Grady, James
2018-01-01
Matching on demographic variables is commonly used in case-control studies to adjust for confounding at the design stage. There is a presumption that matched data need to be analyzed by matched methods. Conditional logistic regression has become a standard for matched case-control data to tackle the sparse data problem. The sparse data problem, however, may not be a concern for loose-matching data when the matching between cases and controls is not unique, and one case can be matched to other controls without substantially changing the association. Data matched on a few demographic variables are clearly loose-matching data, and we hypothesize that unconditional logistic regression is a proper method to perform. To address the hypothesis, we compare unconditional and conditional logistic regression models by precision in estimates and hypothesis testing using simulated matched case-control data. Our results support our hypothesis; however, the unconditional model is not as robust as the conditional model to the matching distortion that the matching process not only makes cases and controls similar for matching variables but also for the exposure status. When the study design involves other complex features or the computational burden is high, matching in loose-matching data can be ignored for negligible loss in testing and estimation if the distributions of matching variables are not extremely different between cases and controls.
Thermal modeling and optimization of a thermally matched energy harvester
Boughaleb, J.; Arnaud, A.; Cottinet, P. J.; Monfray, S.; Gelenne, P.; Kermel, P.; Quenard, S.; Boeuf, F.; Guyomar, D.; Skotnicki, T.
2015-08-01
The interest in energy harvesting devices has grown with the development of wireless sensors requiring small amounts of energy to function. The present article addresses the thermal investigation of a coupled piezoelectric and bimetal-based heat engine. The thermal energy harvester in question converts low-grade heat flows into electrical charges by achieving a two-step conversion mechanism for which the key point is the ability to maintain a significant thermal gradient without any heat sink. Many studies have previously focused on the electrical properties of this innovative device for energy harvesting but until now, no thermal modeling has been able to describe the device specificities or improve its thermal performances. The research reported in this paper focuses on the modeling of the harvester using an equivalent electrical circuit approach. It is shown that the knowledge of the thermal properties inside the device and a good comprehension of its heat exchange with the surrounding play a key role in the optimization procedure. To validate the thermal modeling, finite element analyses as well as experimental measurements on a hot plate were carried out and the techniques were compared. The proposed model provided a practical guideline for improving the generator design to obtain a thermally matched energy harvester that can function over a wide range of hot source temperatures for the same bimetal. A direct application of this study has been implemented on scaled structures to maintain an important temperature difference between the cold surface and the hot reservoir. Using the equations of the thermal model, predictions of the thermal properties were evaluated depending on the scaling factor and solutions for future thermal improvements are presented.
From many body wee partons dynamics to perfect fluid: a standard model for heavy ion collisions
Energy Technology Data Exchange (ETDEWEB)
Venugopalan, R.
2010-07-22
We discuss a standard model of heavy ion collisions that has emerged both from experimental results of the RHIC program and associated theoretical developments. We comment briefly on the impact of early results of the LHC program on this picture. We consider how this standard model of heavy ion collisions could be solidified or falsified in future experiments at RHIC, the LHC and a future Electro-Ion Collider.
Model Adequacy Analysis of Matching Record Versions in Nosql Databases
Directory of Open Access Journals (Sweden)
E. V. Tsviashchenko
2015-01-01
Full Text Available The article investigates a model of matching record versions. The goal of this work is to analyse the model adequacy. This model allows estimating a user’s processing time distribution of the record versions and a distribution of the record versions count. The second option of the model was used, according to which, for a client the time to process record versions depends explicitly on the number of updates, performed by the other users between the sequential updates performed by a current client. In order to prove the model adequacy the real experiment was conducted in the cloud cluster. The cluster contains 10 virtual nodes, provided by DigitalOcean Company. The Ubuntu Server 14.04 was used as an operating system (OS. The NoSQL system Riak was chosen for experiments. In the Riak 2.0 version and later provide “dotted vector versions” (DVV option, which is an extension of the classic vector clock. Their use guarantees, that the versions count, simultaneously stored in DB, will not exceed the count of clients, operating in parallel with a record. This is very important while conducting experiments. For developing the application the java library, provided by Riak, was used. The processes run directly on the nodes. In experiment two records were used. They are: Z – the record, versions of which are handled by clients; RZ – service record, which contains record update counters. The application algorithm can be briefly described as follows: every client reads versions of the record Z, processes its updates using the RZ record counters, and saves treated record in database while old versions are deleted form DB. Then, a client rereads the RZ record and increments counters of updates for the other clients. After that, a client rereads the Z record, saves necessary statistics, and deliberates the results of processing. In the case of emerging conflict because of simultaneous updates of the RZ record, the client obtains all versions of that
Everybody's Different Nobody's Perfect
Everybody's Different, Nobody's Perfect Todos somos diferentes, nadie es perfecto Preschool Edition Edición preescolar Adapted for young children from "Everybody's Different, Nobody's Perfect," by Irwin M. Siegel, M.D., ...
Directory of Open Access Journals (Sweden)
J. Liu
2008-08-01
Full Text Available This paper compares the performance of the Local Ensemble Transform Kalman Filter (LETKF with the Physical-Space Statistical Analysis System (PSAS under a perfect model scenario. PSAS is a 3D-Var assimilation system used operationally in the Goddard Earth Observing System Data Assimilation System (GEOS-4 DAS. The comparison is carried out using simulated winds and geopotential height observations and the finite volume Global Circulation Model with 72 grid points zonally, 46 grid points meridionally and 55 vertical levels. With forty ensemble members, the LETKF obtains analyses and forecasts with significantly lower RMS errors than those from PSAS, especially over the Southern Hemisphere and oceans. This observed advantage of the LETKF over PSAS is due to the ability of the 40-member ensemble LETKF to capture flow-dependent errors and thus create a good estimate of the evolving background uncertainty. An initial decrease of the forecast errors in the Northern Hemisphere observed in the PSAS but not in the LETKF suggests that the LETKF analysis is more balanced.
The complete electroweak effect and perfection of Bhabha scattering in the standard model
International Nuclear Information System (INIS)
Shi Chengye; Fang Zhenyun; Chen Xuewen
2013-01-01
In this paper, we make a close and systematic research on Bhabha scattering in the electroweak unification of the standard model (SM). In concrete research methods we make the quantum field theory of perturbation theory in a new computing mode -renormalization chain propagation theory, and do an application to the Bhabha scattering calculation research. In SM, in order to consider complete electrical weak effect about Bhabha scattering internal process, we seek out the complex renormalization mixing-loop chain propagators constituted by photon y and intermediate boson Z 0 , and then calculate the Bhabha scattering cross section about this kind of propagator by transfer complete electrical weak reaction. Within the observed errors, the calculation results are in good agreement with the experimental values. Also, the main research results not only confirm the action of the particle reaction accuracy by SM theory for describing the electrical weak effect; but also suggests the SM theory may be a per ect theory and that the theory prophecy's Higgs 'mysterious particles' (which is of particular concern in the field of academic) have the large possibility to be eventually found. (authors)
Directory of Open Access Journals (Sweden)
Nikitović Aleksandar
2013-01-01
Full Text Available Early Greek ethics embodied in Cretan and Spartan mores, served as a model for Plato`s political theory. Plato theorized the contents of early Greek ethics, aspiring to justify and revitalize the fundamental principles of a traditional view of the world. However, according to Plato`s new insight, deed is further from the truth than a thought i.e. theory. The dorian model had to renounce its position to the perfect prototype of a righteous state, which is a result of the inner logic of philosophical theorizing in early Greek ethics. Prototype and model of philosophical reflection, in comparison to philosophical theory, becomes minor and deficient. Philosophical theorizing of early Greek ethics philosophically formatted Greek heritage, initiating substantial changes to the content of traditional ethics. Replacement of the myth with ontology, as a new foundation of politics, transformed early Greek ethics in various relevant ways. [Projekat Ministarstva nauke Republike Srbije, br. 179049
International Nuclear Information System (INIS)
Portugal, R.
1984-01-01
Three processes of solutions of the Einstein-Maxwell equations for Bianchi - I, II, VIII, IX and Kantowski-Sachs-like cosmological models with perfect fluid in magnetohydrolodynamical regimem are presented. Diagonal Bianchi-like models are considered with two anisotropy direction in the maximum. Solutions are found for Bianchi-II and IX-like models with energy conditions to be analyzed. Solutions are found for Bianchi-IX and Kantowski-Sachs-Like models with positive electric conductivity and satisfering to the predominant energy conditions. Solutions are formed for isotropic Kantowski-Sachs-Like models satisfering to the equation of state p=λρ, 0 0, admiting, in addition to the perfect fluid, electric field only. It is shown that a class of Bertotti-Robinson-like solutions is unstable by perturbations and it is carried in Kantowski-Sachs-like models with non-null electric conductivity. (L.C.) [pt
Can simple population genetic models reconcile partial match ...
Indian Academy of Sciences (India)
the product rule, population substructure, and relatedness to predict the expected number of matches in large databases. I find that there is a relatively narrow window of parameter values that can plausibly describe the Arizona results. Fur- ther research could help determine if the Arizona samples are congruent with some ...
Generating Models of a Matched Formula with a Polynomial Delay
Czech Academy of Sciences Publication Activity Database
Savický, Petr; Kučera, P.
2016-01-01
Roč. 56, č. 6 (2016), s. 379-402 ISSN 1076-9757 R&D Projects: GA ČR GBP202/12/G061 Grant - others:GA ČR(CZ) GA15-15511S Institutional support: RVO:67985807 Keywords : conjunctive normal form * matched formula * pure literal satisfiable formula Subject RIV: BA - General Mathematics Impact factor: 2.284, year: 2016
Saebi, Tina; Foss, Nicolai Juul
2015-01-01
-This is the author's version of the article:"Business models for open innovation: Matching heterogeneous open innovation strategies with business model dimensions", European Management Journal, Volume 33, Issue 3, June 2015, Pages 201–213 Research on open innovation suggests that companies benefit differentially from adopting open innovation strategies; however, it is unclear why this is so. One possible explanation is that companies' business models are not attuned to open strategies. Ac...
Determination of lower and upper bounds of predicted production from history-matched models
van Essen, G. M.; Kahrobaei, S.S.; van Oeveren, H.; van den Hof, P.M.J.; Jansen, J.D.
2016-01-01
We present a method to determine lower and upper bounds to the predicted production or any other economic objective from history-matched reservoir models. The method consists of two steps: 1) performing a traditional computer-assisted history match of a reservoir model with the objective to
A match-mismatch test of a stage model of behaviour change in tobacco smoking
Dijkstra, A; Conijn, B; De Vries, H
Aims An innovation offered by stage models of behaviour change is that of stage-matched interventions. Match-mismatch studies are the primary test of this idea but also the primary test of the validity of stage models. This study aimed at conducting such a test among tobacco smokers using the Social
Scientist Role Models in the Classroom: How Important Is Gender Matching?
Conner, Laura D. Carsten; Danielson, Jennifer
2016-01-01
Gender-matched role models are often proposed as a mechanism to increase identification with science among girls, with the ultimate aim of broadening participation in science. While there is a great deal of evidence suggesting that role models can be effective, there is mixed support in the literature for the importance of gender matching. We used…
Hayduk, Leslie
2014-01-01
Researchers using factor analysis tend to dismiss the significant ill fit of factor models by presuming that if their factor model is close-to-fitting, it is probably close to being properly causally specified. Close fit may indeed result from a model being close to properly causally specified, but close-fitting factor models can also be seriously…
Weak Memory Models with Matching Axiomatic and Operational Definitions
Zhang, Sizhuo; Vijayaraghavan, Muralidaran; Lustig, Dan; Arvind
2017-01-01
Memory consistency models are notorious for being difficult to define precisely, to reason about, and to verify. More than a decade of effort has gone into nailing down the definitions of the ARM and IBM Power memory models, and yet there still remain aspects of those models which (perhaps surprisingly) remain unresolved to this day. In response to these complexities, there has been somewhat of a recent trend in the (general-purpose) architecture community to limit new memory models to being ...
MATCHING AERIAL IMAGES TO 3D BUILDING MODELS BASED ON CONTEXT-BASED GEOMETRIC HASHING
Directory of Open Access Journals (Sweden)
J. Jung
2016-06-01
Full Text Available In this paper, a new model-to-image framework to automatically align a single airborne image with existing 3D building models using geometric hashing is proposed. As a prerequisite process for various applications such as data fusion, object tracking, change detection and texture mapping, the proposed registration method is used for determining accurate exterior orientation parameters (EOPs of a single image. This model-to-image matching process consists of three steps: 1 feature extraction, 2 similarity measure and matching, and 3 adjustment of EOPs of a single image. For feature extraction, we proposed two types of matching cues, edged corner points representing the saliency of building corner points with associated edges and contextual relations among the edged corner points within an individual roof. These matching features are extracted from both 3D building and a single airborne image. A set of matched corners are found with given proximity measure through geometric hashing and optimal matches are then finally determined by maximizing the matching cost encoding contextual similarity between matching candidates. Final matched corners are used for adjusting EOPs of the single airborne image by the least square method based on co-linearity equations. The result shows that acceptable accuracy of single image's EOP can be achievable by the proposed registration approach as an alternative to labour-intensive manual registration process.
Directory of Open Access Journals (Sweden)
Alexander Yu. Sulimov
2015-01-01
Full Text Available The article is devoted to technique «Perfect demand illusion», which allows to strengthen the competitive advantageof retailers. Also in the paper spells out the golden rules of visual merchandising.The deﬁnition of the method «Demand illusion», formulated the conditions of its functioning, and is determined by the mainhypothesis of the existence of this method.Furthermore, given the deﬁnition of the «Perfect demand illusion», and describes its additional conditions. Also spells out the advantages of the «Perfect demandillusion», before the «Demand illusion».
Model-reduced gradient-based history matching
Kaleta, M.P.
2011-01-01
Since the world's energy demand increases every year, the oil & gas industry makes a continuous effort to improve fossil fuel recovery. Physics-based petroleum reservoir modeling and closed-loop model-based reservoir management concept can play an important role here. In this concept measured data
Model-based shape matching of orthopaedic implants in RSA and fluoroscopy
Prins, Anne Hendrik
2015-01-01
Model-based shape matching is commonly used, for example to measure the migration of an implant with Roentgen stereophotogrammetric analysis (RSA) or to measure implant kinematics with fluoroscopy. The aim of this thesis was to investigate the general usability of shape matching and to improve the
DEFF Research Database (Denmark)
Svenningsen, Stig Roar; Brandt, Jesper; Christensen, Andreas Aagaard
the rotational system. At first the survey campaign seems to be going very well, but relative quickly did the military run into problems. The rapid urbanization of the landscape north of Copenhagen meant, that farming did not take place and at the island of Amager southwest of Copenhagen the farmers didn’t use......Anthropogenic land use practices are the single most important factor in the changing European landscapes. Respectively much attention has been devoted within Landscape Ecology to analyze changing patterns of land use and develop research strategies to understand the processes behind these changes...... and to inform policy makers. Models are used as an important tool in this research partly due to the revolution in information technologies during the last 30 years, which has made modeling more widespread in the research community. However modeling human decision making in form of land use practices...
Endogenizing technological change. Matching empirical evidence to modeling needs
Energy Technology Data Exchange (ETDEWEB)
Pizer, William A. [Resources for the Future, 1616 P Street NW, Washington, DC, 20009 (United States); Popp, David [Department of Public Administration, Center for Policy Research, The Maxwell School, Syracuse University, 426 Eggers Hall, Syracuse, NY 13244-1020 (United States); National Bureau of Economic Research (United States)
2008-11-15
Given that technologies to significantly reduce fossil fuel emissions are currently unavailable or only available at high cost, technological change will be a key component of any long-term strategy to reduce greenhouse gas emissions. In light of this, the amount of research on the pace, direction, and benefits of environmentally-friendly technological change has grown dramatically in recent years. This research includes empirical work estimating the magnitude of these effects, and modeling exercises designed to simulate the importance of endogenous technological change in response to climate policy. Unfortunately, few attempts have been made to connect these two streams of research. This paper attempts to bridge that gap. We review both the empirical and modeling literature on technological change. Our focus includes the research and development process, learning by doing, the role of public versus private research, and technology diffusion. Our goal is to provide an agenda for how both empirical and modeling research in these areas can move forward in a complementary fashion. In doing so, we discuss both how models used for policy evaluation can better capture empirical phenomena, and how empirical research can better address the needs of models used for policy evaluation. (author)
Endogenizing technological change: Matching empirical evidence to modeling needs
Energy Technology Data Exchange (ETDEWEB)
Pizer, William A. [Resources for the Future, 1616 P Street NW, Washington, DC, 20009 (United States)], E-mail: pizer@rff.org; Popp, David [Department of Public Administration, Center for Policy Research, Maxwell School, Syracuse University, 426 Eggers Hall, Syracuse, NY 13244-1020 (United States); National Bureau of Economic Research (United States)], E-mail: dcpopp@maxwell.syr.edu
2008-11-15
Given that technologies to significantly reduce fossil fuel emissions are currently unavailable or only available at high cost, technological change will be a key component of any long-term strategy to reduce greenhouse gas emissions. In light of this, the amount of research on the pace, direction, and benefits of environmentally-friendly technological change has grown dramatically in recent years. This research includes empirical work estimating the magnitude of these effects, and modeling exercises designed to simulate the importance of endogenous technological change in response to climate policy. Unfortunately, few attempts have been made to connect these two streams of research. This paper attempts to bridge that gap. We review both the empirical and modeling literature on technological change. Our focus includes the research and development process, learning by doing, the role of public versus private research, and technology diffusion. Our goal is to provide an agenda for how both empirical and modeling research in these areas can move forward in a complementary fashion. In doing so, we discuss both how models used for policy evaluation can better capture empirical phenomena, and how empirical research can better address the needs of models used for policy evaluation.
Pair Hidden Markov Model for Named Entity Matching
Nabende, P.; Tiedemann, J.; Nerbonne, J.; Sobh, T.
2010-01-01
This paper introduces a pair-Hidden Markov Model (pair-HMM) for the task of evaluating the similarity between bilingual named entities. The pair-HMM is adapted from Mackay and Kondrak [1] who used it on the task of cognate identification and was later adapted by Wieling et al. [5] for Dutch dialect
Models of Jupiter's Interior that match Juno's Gravity Measurements
Militzer, B.; Wahl, S. M.; Hubbard, W. B.; Guillot, T.; Miguel, Y.; Kaspi, Y.; Galanti, E.; Iess, L.; Folkner, W. M.; Helled, R.; Durante, D.; Parisi, M.; Lunine, J. I.; Bloxham, J.; Levin, S.; Connerney, J. E. P.; Stevenson, D. J.; Bolton, S. J.
2017-12-01
Since the Juno spacecraft entered into orbit around Jupiter in July of 2016, it has performed a number of remarkable measurements. With every close flyby, we obtain a new set of precise gravity data that allow us to constrain the planet's gravitational field with unprecedented precision. Already with the first two flybys, the field was constrained by one order of magnitude better than before and a discrepancy between contradictory sets of gravitational coefficients was settled immediately (Folkner et al. 2017, Bolton et al. 2017). However, the new measurements turned out to be a challenge to interpret. A number of new interior models have been constructed already. It appears that models with a dilute core are favored, suggesting that the heavy elements in the planet's center, that were essential for the planet's formation, are now spread out over a substantial fraction of the planets interior (Wahl et al. 2017). In this talk, we will also discuss the gravity signal of the atmospheric and deep interior flows. We will show that interior models can be used to derive constraints on how deep the observable zonal jets can penetrate into the planet's interior. We will relate our predictions to physical changes in the dense fluid that is composed of hydrogen, helium, and a small but important component of heavier elements. The central goal of our modeling effort is a new understanding of Jupiter's interior and origin that combines all the gravity, microwave, and magnetic field observations of the Juno spacecraft.
Hybrid ontology for semantic information retrieval model using keyword matching indexing system.
Uthayan, K R; Mala, G S Anandha
2015-01-01
Ontology is the process of growth and elucidation of concepts of an information domain being common for a group of users. Establishing ontology into information retrieval is a normal method to develop searching effects of relevant information users require. Keywords matching process with historical or information domain is significant in recent calculations for assisting the best match for specific input queries. This research presents a better querying mechanism for information retrieval which integrates the ontology queries with keyword search. The ontology-based query is changed into a primary order to predicate logic uncertainty which is used for routing the query to the appropriate servers. Matching algorithms characterize warm area of researches in computer science and artificial intelligence. In text matching, it is more dependable to study semantics model and query for conditions of semantic matching. This research develops the semantic matching results between input queries and information in ontology field. The contributed algorithm is a hybrid method that is based on matching extracted instances from the queries and information field. The queries and information domain is focused on semantic matching, to discover the best match and to progress the executive process. In conclusion, the hybrid ontology in semantic web is sufficient to retrieve the documents when compared to standard ontology.
Random Matching Models and Money : The Global Structure and Approximation of Stationary Equilibria
Kamiya, K.; Talman, A.J.J.
2003-01-01
Random matching models with different states are an important class of dynamic games; for example, money search models, job search models, and some games in biology are special cases.In this paper, we investigate the basic structure of the models: the existence of equilibria, the global structure of
Conditions for Model Matching of Switched Asynchronous Sequential Machines with Output Feedback
Jung–Min Yang
2016-01-01
Solvability of the model matching problem for input/output switched asynchronous sequential machines is discussed in this paper. The control objective is to determine the existence condition and design algorithm for a corrective controller that can match the stable-state behavior of the closed-loop system to that of a reference model. Switching operations and correction procedures are incorporated using output feedback so that the controlled switched machine can show the ...
Matching Aerial Images to 3D Building Models Using Context-Based Geometric Hashing
Jung, Jaewook; Sohn, Gunho; Bang, Kiin; Wichmann, Andreas; Armenakis, Costas; Kada, Martin
2016-01-01
A city is a dynamic entity, which environment is continuously changing over time. Accordingly, its virtual city models also need to be regularly updated to support accurate model-based decisions for various applications, including urban planning, emergency response and autonomous navigation. A concept of continuous city modeling is to progressively reconstruct city models by accommodating their changes recognized in spatio-temporal domain, while preserving unchanged structures. A first critical step for continuous city modeling is to coherently register remotely sensed data taken at different epochs with existing building models. This paper presents a new model-to-image registration method using a context-based geometric hashing (CGH) method to align a single image with existing 3D building models. This model-to-image registration process consists of three steps: (1) feature extraction; (2) similarity measure; and matching, and (3) estimating exterior orientation parameters (EOPs) of a single image. For feature extraction, we propose two types of matching cues: edged corner features representing the saliency of building corner points with associated edges, and contextual relations among the edged corner features within an individual roof. A set of matched corners are found with given proximity measure through geometric hashing, and optimal matches are then finally determined by maximizing the matching cost encoding contextual similarity between matching candidates. Final matched corners are used for adjusting EOPs of the single airborne image by the least square method based on collinearity equations. The result shows that acceptable accuracy of EOPs of a single image can be achievable using the proposed registration approach as an alternative to a labor-intensive manual registration process. PMID:27338410
Matching Aerial Images to 3D Building Models Using Context-Based Geometric Hashing
Directory of Open Access Journals (Sweden)
Jaewook Jung
2016-06-01
Full Text Available A city is a dynamic entity, which environment is continuously changing over time. Accordingly, its virtual city models also need to be regularly updated to support accurate model-based decisions for various applications, including urban planning, emergency response and autonomous navigation. A concept of continuous city modeling is to progressively reconstruct city models by accommodating their changes recognized in spatio-temporal domain, while preserving unchanged structures. A first critical step for continuous city modeling is to coherently register remotely sensed data taken at different epochs with existing building models. This paper presents a new model-to-image registration method using a context-based geometric hashing (CGH method to align a single image with existing 3D building models. This model-to-image registration process consists of three steps: (1 feature extraction; (2 similarity measure; and matching, and (3 estimating exterior orientation parameters (EOPs of a single image. For feature extraction, we propose two types of matching cues: edged corner features representing the saliency of building corner points with associated edges, and contextual relations among the edged corner features within an individual roof. A set of matched corners are found with given proximity measure through geometric hashing, and optimal matches are then finally determined by maximizing the matching cost encoding contextual similarity between matching candidates. Final matched corners are used for adjusting EOPs of the single airborne image by the least square method based on collinearity equations. The result shows that acceptable accuracy of EOPs of a single image can be achievable using the proposed registration approach as an alternative to a labor-intensive manual registration process.
Directory of Open Access Journals (Sweden)
Nur Fitri Amalia
2013-12-01
Full Text Available AbstrakTujuan penelitian ini adalah untuk mengetahui keefektifan model kooperatif tipe Make a Match dan model CPS terhadap kemampuan pemecahan masalah dan motivasi belajar sis-wa kelas X pada materi persamaan dan fungsi kuadrat. Populasi dalam penelitian ini adalah siswa kelas X SMA N 1 Subah tahun ajaran 2013/2014. Sampel dalam penelitian ini diam-bil dengan teknik random sampling, yaitu teknik pengambilan sampel dengan acak. Kelas X8 terpilih sebagai kelas eksperimen I dengan penerapan model kooperatif tipe Make a Match dan kelas X7 terpilih sebagai kelas eksperimen II dengan penerapan model CPS. Da-ta hasil penelitian diperoleh dengan tes dan pemberian angket untuk kemudian dianalisis menggunakan uji proporsi dan uji t. Hasil penelitian adalah (1 implementasi model koope-ratif tipe Make a Match efektif terhadap kemampuan pemecahan masalah; (2 implementasi model CPS efektif terhadap kemampuan pemecahan masalah; (3 implementasi model koo-peratif tipe Make a Match lebih baik daripada model CPS terhadap kemampuan pecahan masalah; (4 implementasi model CPS lebih baik daripada model kooperatif tipe Make a Match terhadap motivasi belajar.Kata Kunci: Make A Match; CPS; Pemecahan Masalah; Motivasi AbstractThe purpose of this study was to determine the effectiveness of cooperative models Make a Match and CPS to problem-solving ability and motivation of students of class X in the equation of matter and quadratic function. The population of this study was the tenth grade students of state senior high school 1 Subah academic year 2013/2014. The samples in this study were taken by random sampling technique, that is sampling techniques with random. Class X8 was selected as the experimental class I with the application of cooperative model make a Match and class X7 was selected as the experimental class II with the application of the CPS. The data were obtained with the administration of a questionnaire to test and then analyzed using the
Wages, Training, and Job Turnover in a Search-Matching Model
DEFF Research Database (Denmark)
Rosholm, Michael; Nielsen, Michael Svarer
1999-01-01
In this paper we extend a job search-matching model with firm-specific investments in training developed by Mortensen (1998) to allow for different offer arrival rates in employment and unemployment. The model by Mortensen changes the original wage posting model (Burdett and Mortensen, 1998) in two...
Perfect transmission at oblique incidence by trigonal warping in graphene P-N junctions
Zhang, Shu-Hui; Yang, Wen
2018-01-01
We develop an analytical mode-matching technique for the tight-binding model to describe electron transport across graphene P-N junctions. This method shares the simplicity of the conventional mode-matching technique for the low-energy continuum model and the accuracy of the tight-binding model over a wide range of energies. It further reveals an interesting phenomenon on a sharp P-N junction: the disappearance of the well-known Klein tunneling (i.e., perfect transmission) at normal incidence and the appearance of perfect transmission at oblique incidence due to trigonal warping at energies beyond the linear Dirac regime. We show that this phenomenon arises from the conservation of a generalized pseudospin in the tight-binding model. We expect this effect to be experimentally observable in graphene and other Dirac fermions systems, such as the surface of three-dimensional topological insulators.
A Deep Similarity Metric Learning Model for Matching Text Chunks to Spatial Entities
Ma, K.; Wu, L.; Tao, L.; Li, W.; Xie, Z.
2017-12-01
The matching of spatial entities with related text is a long-standing research topic that has received considerable attention over the years. This task aims at enrich the contents of spatial entity, and attach the spatial location information to the text chunk. In the data fusion field, matching spatial entities with the corresponding describing text chunks has a big range of significance. However, the most traditional matching methods often rely fully on manually designed, task-specific linguistic features. This work proposes a Deep Similarity Metric Learning Model (DSMLM) based on Siamese Neural Network to learn similarity metric directly from the textural attributes of spatial entity and text chunk. The low-dimensional feature representation of the space entity and the text chunk can be learned separately. By employing the Cosine distance to measure the matching degree between the vectors, the model can make the matching pair vectors as close as possible. Mearnwhile, it makes the mismatching as far apart as possible through supervised learning. In addition, extensive experiments and analysis on geological survey data sets show that our DSMLM model can effectively capture the matching characteristics between the text chunk and the spatial entity, and achieve state-of-the-art performance.
Bacon, David
2010-01-01
The United States today faces an economic crisis worse than any since the Great Depression of the 1930s. Nowhere is it sharper than in the nation's schools. Last year, California saw a perfect storm of protest in virtually every part of its education system. K-12 teachers built coalitions with parents and students to fight for their jobs and their…
Adiabatic perturbations in pre-big bang models: Matching conditions and scale invariance
International Nuclear Information System (INIS)
Durrer, Ruth; Vernizzi, Filippo
2002-01-01
At low energy, the four-dimensional effective action of the ekpyrotic model of the universe is equivalent to a slightly modified version of the pre-big bang model. We discuss cosmological perturbations in these models. In particular we address the issue of matching the perturbations from a collapsing to an expanding phase. We show that, under certain physically motivated and quite generic assumptions on the high energy corrections, one obtains n=0 for the spectrum of scalar perturbations in the original pre-big bang model (with a vanishing potential). With the same assumptions, when an exponential potential for the dilaton is included, a scale invariant spectrum (n=1) of adiabatic scalar perturbations is produced under very generic matching conditions, both in a modified pre-big bang and ekpyrotic scenario. We also derive the resulting spectrum for arbitrary power law scale factors matched to a radiation-dominated era
The perfect family: decision making in biparental care.
Directory of Open Access Journals (Sweden)
Erol Akçay
Full Text Available Previous theoretical work on parental decisions in biparental care has emphasized the role of the conflict between evolutionary interests of parents in these decisions. A prominent prediction from this work is that parents should compensate for decreases in each other's effort, but only partially so. However, experimental tests that manipulate parents and measure their responses fail to confirm this prediction. At the same time, the process of parental decision making has remained unexplored theoretically. We develop a model to address the discrepancy between experiments and the theoretical prediction, and explore how assuming different decision making processes changes the prediction from the theory.We assume that parents make decisions in behavioral time. They have a fixed time budget, and allocate it between two parental tasks: provisioning the offspring and defending the nest. The proximate determinant of the allocation decisions are parents' behavioral objectives. We assume both parents aim to maximize the offspring production from the nest. Experimental manipulations change the shape of the nest production function. We consider two different scenarios for how parents make decisions: one where parents communicate with each other and act together (the perfect family, and one where they do not communicate, and act independently (the almost perfect family.The perfect family model is able to generate all the types of responses seen in experimental studies. The kind of response predicted depends on the nest production function, i.e. how parents' allocations affect offspring production, and the type of experimental manipulation. In particular, we find that complementarity of parents' allocations promotes matching responses. In contrast, the relative responses do not depend on the type of manipulation in the almost perfect family model. These results highlight the importance of the interaction between nest production function and how parents make
Crystallographic study of grain refinement in aluminum alloys using the edge-to-edge matching model
International Nuclear Information System (INIS)
Zhang, M.-X.; Kelly, P.M.; Easton, M.A.; Taylor, J.A.
2005-01-01
The edge-to-edge matching model for describing the interfacial crystallographic characteristics between two phases that are related by reproducible orientation relationships has been applied to the typical grain refiners in aluminum alloys. Excellent atomic matching between Al 3 Ti nucleating substrates, known to be effective nucleation sites for primary Al, and the Al matrix in both close packed directions and close packed planes containing these directions have been identified. The crystallographic features of the grain refiner and the Al matrix are very consistent with the edge-to-edge matching model. For three other typical grain refiners for Al alloys, TiC (when a = 0.4328 nm), TiB 2 and AlB 2 , the matching only occurs between the close packed directions in both phases and between the second close packed plane of the Al matrix and the second close packed plane of the refiners. According to the model, it is predicted that Al 3 Ti is a more powerful nucleating substrate for Al alloy than TiC, TiB 2 and AlB 2 . This agrees with the previous experimental results. The present work shows that the edge-to-edge matching model has the potential to be a powerful tool in discovering new and more powerful grain refiners for Al alloys
Directory of Open Access Journals (Sweden)
Wuttinan Nunkaew
2013-12-01
Full Text Available At present, methods for solving the manufacturing cell formation with the assignment of duplicated machines contain many steps. Firstly, part families and machine cells are determined. Then, the incidence matrix of the cell formation is reconsidered for machine duplications to reduce the interaction between cells with the restriction of cost. These ways are difficult and complicated. Besides, consideration of machine setup cost should be done simultaneously with the decision making. In this paper, an effective lexicographic fuzzy multi–objective optimization model for manufacturing cell formation with a setup cost constrained of machine duplication is presented. Based on the perfect grouping concept, two crucial performance measures called exceptional elements and void elements are utilized in the proposed model. Lexicographic fuzzy goal programming is applied to solve this multi–objective model with setup cost constraint. So, the decision maker can easily solve the manufacturing cell formation and control the setup cost of machine duplication, simultaneously.
A Frequency Matching Method for Generation of a Priori Sample Models from Training Images
DEFF Research Database (Denmark)
Lange, Katrine; Cordua, Knud Skou; Frydendall, Jan
2011-01-01
This paper presents a Frequency Matching Method (FMM) for generation of a priori sample models based on training images and illustrates its use by an example. In geostatistics, training images are used to represent a priori knowledge or expectations of models, and the FMM can be used to generate...... new images that share the same multi-point statistics as a given training image. The FMM proceeds by iteratively updating voxel values of an image until the frequency of patterns in the image matches the frequency of patterns in the training image; making the resulting image statistically...... indistinguishable from the training image....
Perfect focusing fusion system
International Nuclear Information System (INIS)
Miyamoto, G.; Takeda, T.; Iwata, G.; Mori, S.; Inoue, K.; Tanaka, M.
1994-01-01
We propose new perfect focusing (perfo) fusion systems in which ion- or atom-beam is used as a target for the fusion reaction, and ions (perfo particles) of different species moving in the perfo field collide with them. The 'efficiency' defined as the ratio of the fusion energy output to the radiation loss is ∼300, ∼20, and ∼4 for the T+D, 3 He+D, and 11 B+H reactions, respectively. (author)
A frequency response model matching method for PID controller design for processes with dead-time.
Anwar, Md Nishat; Pan, Somnath
2015-03-01
In this paper, a PID controller design method for the integrating processes based on frequency response matching is presented. Two approaches are proposed for the controller design. In the first approach, a double feedback loop configuration is considered where the inner loop is designed with a stabilizing gain. In the outer loop, the parameters of the PID controller are obtained by frequency response matching between the closed-loop system with the PID controller and a reference model with desired specifications. In the second approach, the design is directly carried out considering a desired load-disturbance rejection model of the system. In both the approaches, two low frequency points are considered for matching the frequency response, which yield linear algebraic equations, solution of which gives the controller parameters. Several examples are taken from the literature to demonstrate the effectiveness and to compare with some well known design methods. Copyright © 2014 ISA. Published by Elsevier Ltd. All rights reserved.
DEFF Research Database (Denmark)
Lykkegaard, Eva; Ulriksen, Lars
2016-01-01
concerning STEM students and attending university. The regular self-to-prototype matching process was shown in real-life role-models meetings to be extended to a more complex three-way matching process between students’ self-perceptions, prototype images and situation-specific conceptions of role models......Previous research has found that young people’s prototypes of science students and scientists affect their inclination to choose tertiary STEM programs. Consequently, many recruitment initiatives include role models to challenge these prototypes. The present study followed 15 STEM-oriented upper......-secondary school students from university-distant backgrounds during and after their participation in an 18-months long university-based recruitment and outreach project involving tertiary STEM students as role models. The analysis focusses on how the students’ meetings with the role models affected their thoughts...
Geenen, R.; Ooijen-van der Linden, L. van; Lumley, M.A.; Bijlsma, J.W.J.; Middendorp, H. van
2012-01-01
OBJECTIVE: Individuals differ in their style of processing emotions (e.g., experiencing affects intensely or being alexithymic) and their strategy of regulating emotions (e.g., expressing or reappraising). A match-mismatch model of emotion processing styles and emotion regulation strategies is
The Robust Control Mixer Method for Reconfigurable Control Design By Using Model Matching Strategy
DEFF Research Database (Denmark)
Yang, Z.; Blanke, Mogens; Verhagen, M.
2001-01-01
This paper proposes a robust reconfigurable control synthesis method based on the combination of the control mixer method and robust H1 con- trol techniques through the model-matching strategy. The control mixer modules are extended from the conventional matrix-form into the LTI sys- tem form. By...... of one space robot arm system subjected to failures....
Modeling Behavior in Different Delay Match to Sample Tasksin One Simple Network
Directory of Open Access Journals (Sweden)
Yali eAmit
2013-07-01
Full Text Available Delay match to sample (DMS experiments provide an important link between the theory of recurrent network models and behavior and neural recordings. We define a simple recurrent network of binary neurons with stochastic neural dynamics and Hebbian synaptic learning. Most DMS experiments involve heavily learned images, and in this setting we propose a readout mechanism for match occurrence based on a smaller increment in overall network activity when the matched pattern is already in working memory, and a reset mechanism to clear memory from stimuli of previous trials using random network activity. Simulations show that this model accounts for a wide range of variations on the original DMS tasks, including ABBA tasks with distractors, and more general repetition detection tasks with both learned and novel images. The differences in network settings required for different tasks derive from easily defined changes in the levels of noise and inhibition. The same models can also explain experiments involving repetition detection with novel images, although in this case the readout mechanism for match is based on higher overall network activity. The models give rise to interesting predictions that may be tested in neural recordings.
Beck, Jeremy M; Springer, Clayton
2014-04-28
The concepts of activity cliffs and matched molecular pairs (MMP) are recent paradigms for analysis of data sets to identify structural changes that may be used to modify the potency of lead molecules in drug discovery projects. Analysis of MMPs was recently demonstrated as a feasible technique for quantitative structure-activity relationship (QSAR) modeling of prospective compounds. Although within a small data set, the lack of matched pairs, and the lack of knowledge about specific chemical transformations limit prospective applications. Here we present an alternative technique that determines pairwise descriptors for each matched pair and then uses a QSAR model to estimate the activity change associated with a chemical transformation. The descriptors effectively group similar transformations and incorporate information about the transformation and its local environment. Use of a transformation QSAR model allows one to estimate the activity change for novel transformations and therefore returns predictions for a larger fraction of test set compounds. Application of the proposed methodology to four public data sets results in increased model performance over a benchmark random forest and direct application of chemical transformations using QSAR-by-matched molecular pairs analysis (QSAR-by-MMPA).
Towards an integrated workflow for structural reservoir model updating and history matching
Leeuwenburgh, O.; Peters, E.; Wilschut, F.
2011-01-01
A history matching workflow, as typically used for updating of petrophysical reservoir model properties, is modified to include structural parameters including the top reservoir and several fault properties: position, slope, throw and transmissibility. A simple 2D synthetic oil reservoir produced by
Using maximum topology matching to explore differences in species distribution models
Poco, Jorge; Doraiswamy, Harish; Talbert, Marian; Morisette, Jeffrey; Silva, Claudio
2015-01-01
Species distribution models (SDM) are used to help understand what drives the distribution of various plant and animal species. These models are typically high dimensional scalar functions, where the dimensions of the domain correspond to predictor variables of the model algorithm. Understanding and exploring the differences between models help ecologists understand areas where their data or understanding of the system is incomplete and will help guide further investigation in these regions. These differences can also indicate an important source of model to model uncertainty. However, it is cumbersome and often impractical to perform this analysis using existing tools, which allows for manual exploration of the models usually as 1-dimensional curves. In this paper, we propose a topology-based framework to help ecologists explore the differences in various SDMs directly in the high dimensional domain. In order to accomplish this, we introduce the concept of maximum topology matching that computes a locality-aware correspondence between similar extrema of two scalar functions. The matching is then used to compute the similarity between two functions. We also design a visualization interface that allows ecologists to explore SDMs using their topological features and to study the differences between pairs of models found using maximum topological matching. We demonstrate the utility of the proposed framework through several use cases using different data sets and report the feedback obtained from ecologists.
Rodriguez, Alvaro; Fernandez-Lozano, Carlos; Dorado, Julian; Rabuñal, Juan R
2014-06-01
Block-matching techniques have been widely used in the task of estimating displacement in medical images, and they represent the best approach in scenes with deformable structures such as tissues, fluids, and gels. In this article, a new iterative block-matching technique-based on successive deformation, search, fitting, filtering, and interpolation stages-is proposed to measure elastic displacements in two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) images. The proposed technique uses different deformation models in the task of correlating proteins in real 2D electrophoresis gel images, obtaining an accuracy of 96.6% and improving the results obtained with other techniques. This technique represents a general solution, being easy to adapt to different 2D deformable cases and providing an experimental reference for block-matching algorithms. Copyright © 2014 Elsevier Inc. All rights reserved.
Directory of Open Access Journals (Sweden)
Yuankun Li
2018-02-01
Full Text Available Although correlation filter (CF-based visual tracking algorithms have achieved appealing results, there are still some problems to be solved. When the target object goes through long-term occlusions or scale variation, the correlation model used in existing CF-based algorithms will inevitably learn some non-target information or partial-target information. In order to avoid model contamination and enhance the adaptability of model updating, we introduce the keypoints matching strategy and adjust the model learning rate dynamically according to the matching score. Moreover, the proposed approach extracts convolutional features from a deep convolutional neural network (DCNN to accurately estimate the position and scale of the target. Experimental results demonstrate that the proposed tracker has achieved satisfactory performance in a wide range of challenging tracking scenarios.
A random point process model for the score in sport matches
Czech Academy of Sciences Publication Activity Database
Volf, Petr
2009-01-01
Roč. 20, č. 2 (2009), s. 121-131 ISSN 1471-678X R&D Projects: GA AV ČR(CZ) IAA101120604 Institutional research plan: CEZ:AV0Z10750506 Keywords : sport statistics * scoring intensity * Cox’s regression model Subject RIV: BB - Applied Statistics, Operational Research http://library.utia.cas.cz/separaty/2009/SI/volf-a random point process model for the score in sport matches.pdf
Energy Technology Data Exchange (ETDEWEB)
Goeke, R.; Farnsworth, A.V.; Neumann, C.C.; Sweatt, W.C.; Warren, M.E.; Weed, J.W.
1996-06-01
This report discusses a novel fabrication process to produce nearly perfect optics. The process utilizes vacuum deposition techniques to optimally modify polished optical substrate surfaces. The surface figure, i.e. contour of a polished optical element, is improved by differentially filling in the low spots on the surface using flux from a physical vapor deposition source through an appropriate mask. The process is expected to enable the manufacture of diffraction-limited optical systems for the UV, extreme UV, and soft X-ray spectral regions, which would have great impact on photolithography and astronomy. This same technique may also reduce the fabrication cost of visible region optics with aspheric surfaces.
Thompson, Robert Bruce
2006-01-01
This popular Build-It-Yourself (BIY) PC book covers everything you want to know about building your own system: Planning and picking out the right components, step-by-step instructions for assembling your perfect PC, and an insightful discussion of why you'd want to do it in the first place. Most big brand computers from HP, Dell and others use lower-quality components so they can meet their aggressive pricing targets. But component manufacturers also make high-quality parts that you can either purchase directly, or obtain through distributors and resellers. Consumers and corporations
Noh, Myoung-Jong; Howat, Ian M.
2018-02-01
The quality and efficiency of automated Digital Elevation Model (DEM) extraction from stereoscopic satellite imagery is critically dependent on the accuracy of the sensor model used for co-locating pixels between stereo-pair images. In the absence of ground control or manual tie point selection, errors in the sensor models must be compensated with increased matching search-spaces, increasing both the computation time and the likelihood of spurious matches. Here we present an algorithm for automatically determining and compensating the relative bias in Rational Polynomial Coefficients (RPCs) between stereo-pairs utilizing hierarchical, sub-pixel image matching in object space. We demonstrate the algorithm using a suite of image stereo-pairs from multiple satellites over a range stereo-photogrammetrically challenging polar terrains. Besides providing a validation of the effectiveness of the algorithm for improving DEM quality, experiments with prescribed sensor model errors yield insight into the dependence of DEM characteristics and quality on relative sensor model bias. This algorithm is included in the Surface Extraction through TIN-based Search-space Minimization (SETSM) DEM extraction software package, which is the primary software used for the U.S. National Science Foundation ArcticDEM and Reference Elevation Model of Antarctica (REMA) products.
Wallis, Thomas S A; Funke, Christina M; Ecker, Alexander S; Gatys, Leon A; Wichmann, Felix A; Bethge, Matthias
2017-10-01
Our visual environment is full of texture-"stuff" like cloth, bark, or gravel as distinct from "things" like dresses, trees, or paths-and humans are adept at perceiving subtle variations in material properties. To investigate image features important for texture perception, we psychophysically compare a recent parametric model of texture appearance (convolutional neural network [CNN] model) that uses the features encoded by a deep CNN (VGG-19) with two other models: the venerable Portilla and Simoncelli model and an extension of the CNN model in which the power spectrum is additionally matched. Observers discriminated model-generated textures from original natural textures in a spatial three-alternative oddity paradigm under two viewing conditions: when test patches were briefly presented to the near-periphery ("parafoveal") and when observers were able to make eye movements to all three patches ("inspection"). Under parafoveal viewing, observers were unable to discriminate 10 of 12 original images from CNN model images, and remarkably, the simpler Portilla and Simoncelli model performed slightly better than the CNN model (11 textures). Under foveal inspection, matching CNN features captured appearance substantially better than the Portilla and Simoncelli model (nine compared to four textures), and including the power spectrum improved appearance matching for two of the three remaining textures. None of the models we test here could produce indiscriminable images for one of the 12 textures under the inspection condition. While deep CNN (VGG-19) features can often be used to synthesize textures that humans cannot discriminate from natural textures, there is currently no uniformly best model for all textures and viewing conditions.
A mixture model for robust point matching under multi-layer motion.
Directory of Open Access Journals (Sweden)
Jiayi Ma
Full Text Available This paper proposes an efficient mixture model for establishing robust point correspondences between two sets of points under multi-layer motion. Our algorithm starts by creating a set of putative correspondences which can contain a number of false correspondences, or outliers, in addition to the true correspondences (inliers. Next we solve for correspondence by interpolating a set of spatial transformations on the putative correspondence set based on a mixture model, which involves estimating a consensus of inlier points whose matching follows a non-parametric geometrical constraint. We formulate this as a maximum a posteriori (MAP estimation of a Bayesian model with hidden/latent variables indicating whether matches in the putative set are outliers or inliers. We impose non-parametric geometrical constraints on the correspondence, as a prior distribution, in a reproducing kernel Hilbert space (RKHS. MAP estimation is performed by the EM algorithm which by also estimating the variance of the prior model (initialized to a large value is able to obtain good estimates very quickly (e.g., avoiding many of the local minima inherent in this formulation. We further provide a fast implementation based on sparse approximation which can achieve a significant speed-up without much performance degradation. We illustrate the proposed method on 2D and 3D real images for sparse feature correspondence, as well as a public available dataset for shape matching. The quantitative results demonstrate that our method is robust to non-rigid deformation and multi-layer/large discontinuous motion.
3D modelling of trompe l'oeil decorated vaults using dense matching techniques
Chiabrando, F.; Lingua, A.; Noardo, F.; Spano, A.
2014-05-01
Dense matching techniques, implemented in many commercial and open source software, are useful instruments for carrying out a rapid and detailed analysis of complex objects, including various types of details and surfaces. For this reason these tools were tested in the metric survey of a frescoed ceiling in the hall of honour of a baroque building. The surfaces are covered with trompe-l'oeil paintings which theoretically can give a very good texture to automatic matching algorithms but in this case problems arise when attempting to reconstruct the correct geometry: in fact, in correspondence with the main architectonic painted details, the models present some irregularities, unexpectedly coherent with the painted drawing. The photogrammetric models have been compared with data deriving from a LIDAR survey of the same object, to evaluate the entity of this blunder: some profiles of selected sections have been extracted, verifying the different behaviours of the software tools.
Metamaterials for perfect absorption
Lee, Young Pak; Yoo, Young Joon; Kim, Ki Won
2016-01-01
This book provides a comprehensive overview of the theory and practical development of metamaterial-based perfect absorbers (MMPAs). It begins with a brief history of MMPAs which reviews the various theoretical and experimental milestones in their development. The theoretical background and fundamental working principles of MMPAs are then discussed, providing the necessary background on how MMPAs work and are constructed. There then follows a section describing how different MMPAs are designed and built according to the operating frequency of the electromagnetic wave, and how their behavior is changed. Methods of fabricating and characterizing MMPAs are then presented. The book elaborates on the performance and characteristics of MMPAs, including electromagnetically-induced transparency (EIT). It also covers recent advances in MMPAs and their applications, including multi-band, broadband, tunability, polarization independence and incidence independence. Suitable for graduate students in optical sciences and e...
Gender Discrimination Estimation in a Search Model with Matching and Bargaining
Luca Flabbi
2004-01-01
Gender wage differentials, conditional on observed productivity characteristics, have been considered a possible indication of prejudice against women in the labor market. However, there is no conclusive evidence on whether these differentials are due to labor market discrimination or to unobserved productivity differences. The objective of this paper is to propose a solution for this identification problem by developing and estimating a search model of the labor market with matching, bargain...
Robust Control Mixer Method for Reconfigurable Control Design Using Model Matching Strategy
Yang, Zhenyu; Blanke, Mogens; Verhagen, Michel
2007-01-01
A novel control mixer method for recon¯gurable control designs is developed. The proposed method extends the matrix-form of the conventional control mixer concept into a LTI dynamic system-form. The H_inf control technique is employed for these dynamic module designs after an augmented control system is constructed through a model-matching strategy. The stability, performance and robustness of the reconfigured system can be guaranteed when some conditions are satisfied. To illustrate the effe...
The pursuit of perfect packing
Weaire, Denis
2008-01-01
Coauthored by one of the creators of the most efficient space packing solution, the Weaire-Phelan structure, The Pursuit of Perfect Packing, Second Edition explores a problem of importance in physics, mathematics, chemistry, biology, and engineering: the packing of structures. Maintaining its mathematical core, this edition continues and revises some of the stories from its predecessor while adding several new examples and applications. The book focuses on both scientific and everyday problems ranging from atoms to honeycombs. It describes packing models, such as the Kepler conjecture, Voronoï decomposition, and Delaunay decomposition, as well as actual structure models, such as the Kelvin cell and the Weaire-Phelan structure. The authors discuss numerous historical aspects and provide biographical details on influential contributors to the field, including emails from Thomas Hales and Ken Brakke. With examples from physics, crystallography, engineering, and biology, this accessible and whimsical bo...
Directory of Open Access Journals (Sweden)
Eva Lykkegaard
2016-04-01
Full Text Available Previous research has found that young people’s prototypes of science students and scientists affect their inclination to choose tertiary STEM programs (Science, Technology, Engineering and Mathematics. Consequently, many recruitment initiatives include role models to challenge these prototypes. The present study followed 15 STEM-oriented upper-secondary school students from university-distant backgrounds during and after their participation in an 18-months long university-based recruitment and outreach project involving tertiary STEM students as role models. The analysis focusses on how the students’ meetings with the role models affected their thoughts concerning STEM students and attending university. The regular self-to-prototype matching process was shown in real-life role-models meetings to be extended to a more complex three-way matching process between students’ self-perceptions, prototype images and situation-specific conceptions of role models. Furthermore, the study underlined the positive effect of prolonged role-model contact, the importance of using several role models and that traditional school subjects catered more resistant prototype images than unfamiliar ones did.
Jafarzadeh, S Reza; Johnson, Wesley O; Gardner, Ian A
2016-03-15
The area under the receiver operating characteristic (ROC) curve (AUC) is used as a performance metric for quantitative tests. Although multiple biomarkers may be available for diagnostic or screening purposes, diagnostic accuracy is often assessed individually rather than in combination. In this paper, we consider the interesting problem of combining multiple biomarkers for use in a single diagnostic criterion with the goal of improving the diagnostic accuracy above that of an individual biomarker. The diagnostic criterion created from multiple biomarkers is based on the predictive probability of disease, conditional on given multiple biomarker outcomes. If the computed predictive probability exceeds a specified cutoff, the corresponding subject is allocated as 'diseased'. This defines a standard diagnostic criterion that has its own ROC curve, namely, the combined ROC (cROC). The AUC metric for cROC, namely, the combined AUC (cAUC), is used to compare the predictive criterion based on multiple biomarkers to one based on fewer biomarkers. A multivariate random-effects model is proposed for modeling multiple normally distributed dependent scores. Bayesian methods for estimating ROC curves and corresponding (marginal) AUCs are developed when a perfect reference standard is not available. In addition, cAUCs are computed to compare the accuracy of different combinations of biomarkers for diagnosis. The methods are evaluated using simulations and are applied to data for Johne's disease (paratuberculosis) in cattle. Copyright © 2015 John Wiley & Sons, Ltd.
Perfect simulation of Hawkes processes
DEFF Research Database (Denmark)
Møller, Jesper; Rasmussen, Jakob Gulddahl
their branching and conditional independence structure, useful approximations of the distribution function for the length of a cluster are derived. This is used to construct upper and lower processes for the perfect simulation algorithm. Examples of applications and empirical results are presented.......This article concerns a perfect simulation algorithm for unmarked and marked Hawkes processes. The usual stratihtforward simulation algorithm suffers from edge effects, whereas our perfect simulation algorithm does not. By viewing Hawkes processes as Poisson cluster processes and using...
Perfect Taxation with Imperfect Competition
Alan J. Auerbach; James R. Hines Jr.
2001-01-01
This paper analyzes features of perfect taxation also known as optimal taxation when one or more private markets is imperfectly competitive. Governments with perfect information and access to lump-sum taxes can provide corrective subsidies that render outcomes efficient in the presence of imperfect competition. Relaxing either of these two conditions removes the government's ability to support efficient resource allocation and changes the perfect policy response. When governments cannot use l...
Kroonblawd, Matthew P; Pietrucci, Fabio; Saitta, Antonino Marco; Goldman, Nir
2018-03-22
We demonstrate the capability of creating robust density functional tight binding (DFTB) models for chemical reactivity in prebiotic mixtures through force matching to short time scale quantum free energy estimates. Molecular dynamics using density functional theory (DFT) is a highly accurate approach to generate free energy surfaces for chemical reactions, but the extreme computational cost often limits the time scales and range of thermodynamic states that can feasibly be studied. In contrast, DFTB is a semiempirical quantum method that affords up to a thousandfold reduction in cost and can recover DFT-level accuracy. Here, we show that a force-matched DFTB model for aqueous glycine condensation reactions yields free energy surfaces that are consistent with experimental observations of reaction energetics. Convergence analysis reveals that multiple nanoseconds of combined trajectory are needed to reach a steady-fluctuating free energy estimate for glycine condensation. Predictive accuracy of force-matched DFTB is demonstrated by direct comparison to DFT, with the two approaches yielding surfaces with large regions that differ by only a few kcal mol -1 .
The perfect message at the perfect moment.
Kalyanam, Kirthi; Zweben, Monte
2005-11-01
Marketers planning promotional campaigns ask questions to boost the odds that the messages will be accepted: Who should receive each message? What should be its content? How should we deliver it? The one question they rarely ask is, when should we deliver it? That's too bad, because in marketing, timing is arguably the most important variable of all. Indeed, there are moments in a customer's relationship with a business when she wants to communicate with that business because something has changed. If the company contacts her with the right message in the right format at the right time, there's a good chance of a warm reception. The question of "when" can be answered by a new computer-based model called "dialogue marketing," which is, to date, the highest rung on an evolutionary ladder that ascends from database marketing to relationship marketing to one-to-one marketing. Its principle advantages over older approaches are that it is completely interactive, exploits many communication channels, and is "relationship aware": that is, it continuously tracks every nuance of the customer's interaction with the business. Thus, dialogue marketing responds to each transition in that relationship at the moment the customer requires attention. Turning a traditional marketing strategy into a dialogue-marketing program is a straightforward matter. Begin by identifying the batch communications you make with customers, then ask yourself what events could trigger those communications to make them more timely. Add a question or call to action to each message and prepare a different treatment or response for each possible answer. Finally, create a series of increasingly urgent calls to action that kick in if the question or call to action goes unanswered by the customer. As dialogue marketing proliferates, it may provide the solid new footing that Madison Avenue seeks.
Directory of Open Access Journals (Sweden)
Simone Fiori
2007-07-01
Full Text Available Bivariate statistical modeling from incomplete data is a useful statistical tool that allows to discover the model underlying two data sets when the data in the two sets do not correspond in size nor in ordering. Such situation may occur when the sizes of the two data sets do not match (i.e., there are Ã‚Â“holesÃ‚Â” in the data or when the data sets have been acquired independently. Also, statistical modeling is useful when the amount of available data is enough to show relevant statistical features of the phenomenon underlying the data. We propose to tackle the problem of statistical modeling via a neural (nonlinear system that is able to match its input-output statistic to the statistic of the available data sets. A key point of the new implementation proposed here is that it is based on look-up-table (LUT neural systems, which guarantee a computationally advantageous way of implementing neural systems. A number of numerical experiments, performed on both synthetic and real-world data sets, illustrate the features of the proposed modeling procedure.
Perfect Liberty or Natural Liberty?
DEFF Research Database (Denmark)
Jacobsen, Stefan Gaarsmand
2012-01-01
The article investigates the concept of natural order as it is used by François Quesnay and Adam Smith in their respective economic writings. While Smith used the concept only after having visited Quesnay and the Physiocrats in France in the 1760s, in The Wealth of Nations he sought to negotiate...... the meaning of what was “natural” about economic life. The Physiocrats believed it possible to identify a model or a perfect regime of natural order – an order that they in fact thought to exist and function in China due to a rigorous system of economic laws. Smith sided with contemporary critics...... successors in political economy, and the problem of ordering the society from the vantage point of an economic science was rephrased as a problem of combining the physiocratic metaphysics of natural order with the ‘business of the world’ as expounded by Smith....
Analogue pattern matching in a dendritic spine model based on phosphorylation of potassium channels.
Yang, K H; Blackwell, K T
2000-11-01
Modification of potassium channels by protein phosphorylation has been shown to play a role in learning and memory. If such memory storage machinery were part of dendritic spines, then a set of spines could act as an 'analogue pattern matching' device by learning a repeatedly presented pattern of synaptic activation. In this study, the plausibility of such analogue pattern matching is investigated in a detailed circuit model of a set of spines attached to a dendritic branch. Each spine head contains an AMPA synaptic channel in parallel with a calcium-dependent potassium channel whose sensitivity depends on its phosphorylation state. Repeated presentation of synaptic activity results in calcium activation of protein kinases and subsequent channel phosphorylation. Simulations demonstrate that signal strength is greatest when the synaptic input pattern is equal to the previously learned pattern, and smaller when components of the synaptic input pattern are either smaller or larger than corresponding components of the previously learned pattern. Therefore, our results indicate that dendritic spines may act as an analogue pattern matching device, and suggest that modulation of potassium channels by protein kinases may mediate neuronal pattern recognition.
Action detection by double hierarchical multi-structure space-time statistical matching model
Han, Jing; Zhu, Junwei; Cui, Yiyin; Bai, Lianfa; Yue, Jiang
2018-03-01
Aimed at the complex information in videos and low detection efficiency, an actions detection model based on neighboring Gaussian structure and 3D LARK features is put forward. We exploit a double hierarchical multi-structure space-time statistical matching model (DMSM) in temporal action localization. First, a neighboring Gaussian structure is presented to describe the multi-scale structural relationship. Then, a space-time statistical matching method is proposed to achieve two similarity matrices on both large and small scales, which combines double hierarchical structural constraints in model by both the neighboring Gaussian structure and the 3D LARK local structure. Finally, the double hierarchical similarity is fused and analyzed to detect actions. Besides, the multi-scale composite template extends the model application into multi-view. Experimental results of DMSM on the complex visual tracker benchmark data sets and THUMOS 2014 data sets show the promising performance. Compared with other state-of-the-art algorithm, DMSM achieves superior performances.
Nuclear Forces and High-Performance Computing: The Perfect Match
Energy Technology Data Exchange (ETDEWEB)
Luu, T; Walker-Loud, A
2009-06-12
High-performance computing is now enabling the calculation of certain nuclear interaction parameters directly from Quantum Chromodynamics, the quantum field theory that governs the behavior of quarks and gluons and is ultimately responsible for the nuclear strong force. We briefly describe the state of the field and describe how progress in this field will impact the greater nuclear physics community. We give estimates of computational requirements needed to obtain certain milestones and describe the scientific and computational challenges of this field.
Soil Respiration and Student Inquiry: A Perfect Match
Hoyt, Catherine Marie; Wallenstein, Matthew David
2011-01-01
This activity explores the cycling of carbon between the atmosphere (primarily as CO[subscript 2]) and biomass in plants, animals, and microscopic organisms. Students design soil respiration experiments using a protocol that resembles current practice in soil ecology. Three methods for measuring soil respiration are presented. Student-derived…
Polypeptoids: A perfect match for molecular definition and macromolecular engineering?
Luxenhofer, Robert
2013-04-19
Precision synthesis of polymers has been a hot topic in recent years. While this is notoriously difficult to address for polymers with a Cï£¿C backbone, Merrifield has discovered a way many decades ago for polypeptides. Using a similar approach, N-substituted polypeptides, so-called polypeptoids have been synthesized and studied for about 20 years. In contrast, the living ring-opening polymerization (ROP) of N-substituted N-carboxyanhydrides was among the first living polymerizations to be discovered. More recently, a surge in new synthetic approaches led to the efficient synthesis of cyclic or linear multiblock copolypeptoids. Thus, polypeptoids can be synthesized either by solid phase synthesis to yield complex and exactly defined oligo- and small polymers or by ROP of appropriately N-substituted N-carboxyanhydrides (NNCA) to give linear, cyclic, or star-like polymers. Together with an excellent biocompatibility, this polymer family may have a bright future ahead as biomaterials. © 2013 Wiley Periodicals, Inc.
A perfect match: Nuclear energy and the National Energy Strategy
International Nuclear Information System (INIS)
1990-11-01
In the course of developing the National Energy Strategy, the Department of Energy held 15 public hearings, heard from more than 375 witnesses and received more than 1000 written comments. In April 1990, the Department published an Interim Report on the National Energy Strategy, which compiles those public comments. The National Energy Strategy must be based on actual experience and factual analysis of our energy, economic and environmental situation. This report by the Nuclear Power Oversight committee, which represents electric utilities and other organizations involved in supplying electricity from nuclear energy to the American people, provides such an analysis. The conclusions here are based on hard facts and actual worldwide experience. This analysis of all the available data supports -- indeed, dictates -- expanded reliance on nuclear energy in this nation's energy supply to achieve the President's goals. 33 figs
Artful Teaching and Science Investigations: A Perfect Match
McGee, Christy
2018-01-01
Tomlinson's explanation of Artful Teaching and her 2017 expansion of this concept The Five Key Elements of Differentiation provide the theoretical framework of this examination of the need for science investigations in elementary schools. The Artful Teaching framework uses an equilateral triangle with vertices labeled The Teacher, The Student, and…
Teaching tolerance through English? Yes! A perfect match! / Kati Bakaradze
Bakaradze, Kati
2014-01-01
Ameerika Ühendriikide saatkona toel toimuvatest keelekümbluslaagritest Balti riikide noortele. Projekti eesmärgiks on keskenduda vastastikusele mõistmisele, sallivusele ja austusele olenemata etnilistest ja kultuurilistest erinevustest
Directory of Open Access Journals (Sweden)
Abdenaceur Boudlal
2010-01-01
Full Text Available This article investigates a new method of motion estimation based on block matching criterion through the modeling of image blocks by a mixture of two and three Gaussian distributions. Mixture parameters (weights, means vectors, and covariance matrices are estimated by the Expectation Maximization algorithm (EM which maximizes the log-likelihood criterion. The similarity between a block in the current image and the more resembling one in a search window on the reference image is measured by the minimization of Extended Mahalanobis distance between the clusters of mixture. Performed experiments on sequences of real images have given good results, and PSNR reached 3 dB.
mr. A C++ library for the matching and running of the Standard Model parameters
International Nuclear Information System (INIS)
Kniehl, Bernd A.; Veretin, Oleg L.; Pikelner, Andrey F.; Joint Institute for Nuclear Research, Dubna
2016-01-01
We present the C++ program library mr that allows us to reliably calculate the values of the running parameters in the Standard Model at high energy scales. The initial conditions are obtained by relating the running parameters in the MS renormalization scheme to observables at lower energies with full two-loop precision. The evolution is then performed in accordance with the renormalization group equations with full three-loop precision. Pure QCD corrections to the matching and running are included through four loops. We also provide a Mathematica interface for this program library.
Energy Technology Data Exchange (ETDEWEB)
Ruffio, Jean-Baptiste; Macintosh, Bruce; Nielsen, Eric L.; Czekala, Ian; Bailey, Vanessa P.; Follette, Katherine B. [Kavli Institute for Particle Astrophysics and Cosmology, Stanford University, Stanford, CA, 94305 (United States); Wang, Jason J.; Rosa, Robert J. De; Duchêne, Gaspard [Astronomy Department, University of California, Berkeley CA, 94720 (United States); Pueyo, Laurent [Space Telescope Science Institute, Baltimore, MD, 21218 (United States); Marley, Mark S. [NASA Ames Research Center, Mountain View, CA, 94035 (United States); Arriaga, Pauline; Fitzgerald, Michael P. [Department of Physics and Astronomy, University of California, Los Angeles, CA, 90095 (United States); Barman, Travis [Lunar and Planetary Laboratory, University of Arizona, Tucson AZ, 85721 (United States); Bulger, Joanna [Subaru Telescope, NAOJ, 650 North A’ohoku Place, Hilo, HI 96720 (United States); Chilcote, Jeffrey [Dunlap Institute for Astronomy and Astrophysics, University of Toronto, Toronto, ON, M5S 3H4 (Canada); Cotten, Tara [Department of Physics and Astronomy, University of Georgia, Athens, GA, 30602 (United States); Doyon, Rene [Institut de Recherche sur les Exoplanètes, Départment de Physique, Université de Montréal, Montréal QC, H3C 3J7 (Canada); Gerard, Benjamin L. [University of Victoria, 3800 Finnerty Road, Victoria, BC, V8P 5C2 (Canada); Goodsell, Stephen J., E-mail: jruffio@stanford.edu [Gemini Observatory, 670 N. A’ohoku Place, Hilo, HI, 96720 (United States); and others
2017-06-10
We present a new matched-filter algorithm for direct detection of point sources in the immediate vicinity of bright stars. The stellar point-spread function (PSF) is first subtracted using a Karhunen-Loéve image processing (KLIP) algorithm with angular and spectral differential imaging (ADI and SDI). The KLIP-induced distortion of the astrophysical signal is included in the matched-filter template by computing a forward model of the PSF at every position in the image. To optimize the performance of the algorithm, we conduct extensive planet injection and recovery tests and tune the exoplanet spectra template and KLIP reduction aggressiveness to maximize the signal-to-noise ratio (S/N) of the recovered planets. We show that only two spectral templates are necessary to recover any young Jovian exoplanets with minimal S/N loss. We also developed a complete pipeline for the automated detection of point-source candidates, the calculation of receiver operating characteristics (ROC), contrast curves based on false positives, and completeness contours. We process in a uniform manner more than 330 data sets from the Gemini Planet Imager Exoplanet Survey and assess GPI typical sensitivity as a function of the star and the hypothetical companion spectral type. This work allows for the first time a comparison of different detection algorithms at a survey scale accounting for both planet completeness and false-positive rate. We show that the new forward model matched filter allows the detection of 50% fainter objects than a conventional cross-correlation technique with a Gaussian PSF template for the same false-positive rate.
Perfect simulation of Hawkes processes
DEFF Research Database (Denmark)
Møller, Jesper; Rasmussen, Jakob Gulddahl
2005-01-01
their branching and conditional independence structures, useful approximations of the distribution function for the length of a cluster are derived. This is used to construct upper and lower processes for the perfect simulation algorithm. A tail-lightness condition turns out to be of importance......Our objective is to construct a perfect simulation algorithm for unmarked and marked Hawkes processes. The usual straightforward simulation algorithm suffers from edge effects, whereas our perfect simulation algorithm does not. By viewing Hawkes processes as Poisson cluster processes and using...
Graph configuration model based evaluation of the education-occupation match.
Gadar, Laszlo; Abonyi, Janos
2018-01-01
To study education-occupation matchings we developed a bipartite network model of education to work transition and a graph configuration model based metric. We studied the career paths of 15 thousand Hungarian students based on the integrated database of the National Tax Administration, the National Health Insurance Fund, and the higher education information system of the Hungarian Government. A brief analysis of gender pay gap and the spatial distribution of over-education is presented to demonstrate the background of the research and the resulted open dataset. We highlighted the hierarchical and clustered structure of the career paths based on the multi-resolution analysis of the graph modularity. The results of the cluster analysis can support policymakers to fine-tune the fragmented program structure of higher education.
Directory of Open Access Journals (Sweden)
Aleksandr G. Podvesovskii
2017-12-01
Full Text Available The article deals with an approach for modeling and software support of distribution of students between graduate supervisors at large graduate department. The approach is based on the stable matching problem and the Gale-Shapley deferred acceptance algorithm, and takes into account both students and supervisors’ preferences. The formalized description of distribution model is given, and the results of its practical verification are described. The advantages and disadvantages of the proposed approach are discussed, and the problem of preferences manipulation of graduate supervisors are examined. The architecture of the distribution support software system is presented, and some features of its implementation as a Web-service within the complex information system of the graduate department are described.
Automated side-chain model building and sequence assignment by template matching
International Nuclear Information System (INIS)
Terwilliger, Thomas C.
2002-01-01
A method for automated macromolecular side-chain model building and for aligning the sequence to the map is described. An algorithm is described for automated building of side chains in an electron-density map once a main-chain model is built and for alignment of the protein sequence to the map. The procedure is based on a comparison of electron density at the expected side-chain positions with electron-density templates. The templates are constructed from average amino-acid side-chain densities in 574 refined protein structures. For each contiguous segment of main chain, a matrix with entries corresponding to an estimate of the probability that each of the 20 amino acids is located at each position of the main-chain model is obtained. The probability that this segment corresponds to each possible alignment with the sequence of the protein is estimated using a Bayesian approach and high-confidence matches are kept. Once side-chain identities are determined, the most probable rotamer for each side chain is built into the model. The automated procedure has been implemented in the RESOLVE software. Combined with automated main-chain model building, the procedure produces a preliminary model suitable for refinement and extension by an experienced crystallographer
Bianchi type-I massive string magnetized barotropic perfect fluid ...
Indian Academy of Sciences (India)
by either a perfect fluid or a cosmic string in bimetric theory of gravitation. Bali and Prad- han [41] have investigated Bianchi type-III string cosmological model with time-dependent bulk viscosity. In view of the importance of Maxwell's electromagnetic field interactions with a perfect fluid or a cosmic string and there is a lot of ...
... Spread the Word Shop AAP Find a Pediatrician Family Life Medical Home Family Dynamics Adoption & Foster Care ... Español Text Size Email Print Share The "Perfect" Family Page Content Article Body Is there such a ...
Plummer, MD
1986-01-01
This study of matching theory deals with bipartite matching, network flows, and presents fundamental results for the non-bipartite case. It goes on to study elementary bipartite graphs and elementary graphs in general. Further discussed are 2-matchings, general matching problems as linear programs, the Edmonds Matching Algorithm (and other algorithmic approaches), f-factors and vertex packing.
The Perfective Past Tense in Greek Adolescents with Down Syndrome
Stathopoulou, Nikolitsa; Clahsen, Harald
2010-01-01
This study investigates the ability of a group of eight Greek-speaking adolescents with Down Syndrome (DS) (aged 12.1-18.7) to handle the perfective past tense using an acceptability judgement task. The performance of the DS participants was compared with that of 16 typically-developing children whose chronological age was matched with the mental…
Automated main-chain model building by template matching and iterative fragment extension
International Nuclear Information System (INIS)
Terwilliger, Thomas C.
2003-01-01
A method for automated macromolecular main-chain model building is described. An algorithm for the automated macromolecular model building of polypeptide backbones is described. The procedure is hierarchical. In the initial stages, many overlapping polypeptide fragments are built. In subsequent stages, the fragments are extended and then connected. Identification of the locations of helical and β-strand regions is carried out by FFT-based template matching. Fragment libraries of helices and β-strands from refined protein structures are then positioned at the potential locations of helices and strands and the longest segments that fit the electron-density map are chosen. The helices and strands are then extended using fragment libraries consisting of sequences three amino acids long derived from refined protein structures. The resulting segments of polypeptide chain are then connected by choosing those which overlap at two or more C α positions. The fully automated procedure has been implemented in RESOLVE and is capable of model building at resolutions as low as 3.5 Å. The algorithm is useful for building a preliminary main-chain model that can serve as a basis for refinement and side-chain addition
Rutishauser, This; Stöckli, Reto; Jeanneret, François; Peñuelas, Josep
2010-05-01
Changes in the seasonality of life cycles of plants as recorded in phenological observations have been widely analysed at the species level with data available for many decades back in time. At the same time, seasonality changes in satellite-based observations and prognostic phenology models comprise information at the pixel-size or landscape scale. Change analysis of satellite-based records is restricted due to relatively short satellite records that further include gaps while model-based analyses are biased due to current model deficiencies., At 30 selected sites across Europe, we analysed three different sources of plant seasonality during the 1971-2000 period. Data consisted of (1) species-specific development stages of flowering and leave-out with different species observed at each site. (2) We used a synthetic phenological metric that integrates the common interannual phenological signal across all species at one site. (3) We estimated daily Leaf Area Index with a prognostic phenology model. The prior uncertainties of the model's empirical parameter space are constrained by assimilating the Fraction of Photosynthetically Active Radiation absorbed by vegetation (FPAR) and Leaf Area Index (LAI) from the MODerate Resolution Imaging Spectroradiometer (MODIS). We extracted the day of year when the 25%, 50% and 75% thresholds were passed each spring. The question arises how the three phenological signals compare and correlate across climate zones in Europe. Is there a match between single species observations, species-based ground-observed metrics and the landscape-scale prognostic model? Are there single key-species across Europe that best represent a landscape scale measure from the prognostic model? Can one source substitute another and serve as proxy-data? What can we learn from potential mismatches? Focusing on changes in spring this contribution presents first results of an ongoing comparison study from a number of European test sites that will be extended to
On Improving Analytical Models of Cosmic Reionization for Matching Numerical Simulations
Energy Technology Data Exchange (ETDEWEB)
Kaurov, Alexander A. [Univ. of Chicago, IL (United States)
2016-01-01
The methods for studying the epoch of cosmic reionization vary from full radiative transfer simulations to purely analytical models. While numerical approaches are computationally expensive and are not suitable for generating many mock catalogs, analytical methods are based on assumptions and approximations. We explore the interconnection between both methods. First, we ask how the analytical framework of excursion set formalism can be used for statistical analysis of numerical simulations and visual representation of the morphology of ionization fronts. Second, we explore the methods of training the analytical model on a given numerical simulation. We present a new code which emerged from this study. Its main application is to match the analytical model with a numerical simulation. Then, it allows one to generate mock reionization catalogs with volumes exceeding the original simulation quickly and computationally inexpensively, meanwhile reproducing large scale statistical properties. These mock catalogs are particularly useful for CMB polarization and 21cm experiments, where large volumes are required to simulate the observed signal.
Directory of Open Access Journals (Sweden)
Patricia Puerta
Full Text Available Populations of the same species can experience different responses to the environment throughout their distributional range as a result of spatial and temporal heterogeneity in habitat conditions. This highlights the importance of understanding the processes governing species distribution at local scales. However, research on species distribution often averages environmental covariates across large geographic areas, missing variability in population-environment interactions within geographically distinct regions. We used spatially explicit models to identify interactions between species and environmental, including chlorophyll a (Chla and sea surface temperature (SST, and trophic (prey density conditions, along with processes governing the distribution of two cephalopods with contrasting life-histories (octopus and squid across the western Mediterranean Sea. This approach is relevant for cephalopods, since their population dynamics are especially sensitive to variations in habitat conditions and rarely stable in abundance and location. The regional distributions of the two cephalopod species matched two different trophic pathways present in the western Mediterranean Sea, associated with the Gulf of Lion upwelling and the Ebro river discharges respectively. The effects of the studied environmental and trophic conditions were spatially variant in both species, with usually stronger effects along their distributional boundaries. We identify areas where prey availability limited the abundance of cephalopod populations as well as contrasting effects of temperature in the warmest regions. Despite distributional patterns matching productive areas, a general negative effect of Chla on cephalopod densities suggests that competition pressure is common in the study area. Additionally, results highlight the importance of trophic interactions, beyond other common environmental factors, in shaping the distribution of cephalopod populations. Our study presents
1984-10-01
and mental stresses , strategies, tactics, and teamwork. As the brief description of the athletic training model unfolds, more analogies to the fighter...performance levels, stress and anxiety all interrelate to determine level of performance. Many are familiar with stories of athletes who seemed to excel in the...with stress and anxiety has become a very important area of R&D and application in sports psychology. It should also become an R&D area for aviation
Perfect secure domination in graphs
Directory of Open Access Journals (Sweden)
S.V. Divya Rashmi
2017-07-01
Full Text Available Let $G=(V,E$ be a graph. A subset $S$ of $V$ is a dominating set of $G$ if every vertex in $Vsetminus S$ is adjacent to a vertex in $S.$ A dominating set $S$ is called a secure dominating set if for each $vin Vsetminus S$ there exists $uin S$ such that $v$ is adjacent to $u$ and $S_1=(Ssetminus{u}cup {v}$ is a dominating set. If further the vertex $uin S$ is unique, then $S$ is called a perfect secure dominating set. The minimum cardinality of a perfect secure dominating set of $G$ is called the perfect secure domination number of $G$ and is denoted by $gamma_{ps}(G.$ In this paper we initiate a study of this parameter and present several basic results.
Designing the ''perfect'' projection screen
Caulfield, H. John
2005-07-01
A perfect diffuser would place 100% of the light leaving the projector in that small region of space where there will be audience eyes to observe it. It would not allow light from sources other than the projector to reach the eyes from the screen. The screen should be affordably priced and cosmetically unremarkable, e.g. seamless. The image seen by any observer should be equally bright over the whole screen. I discuss a way to approximate the perfect projection screen using kinoform diffusers, a Fresnel lens and a mirrored surface.
mr: A C++ library for the matching and running of the Standard Model parameters
Kniehl, Bernd A.; Pikelner, Andrey F.; Veretin, Oleg L.
2016-09-01
We present the C++ program library mr that allows us to reliably calculate the values of the running parameters in the Standard Model at high energy scales. The initial conditions are obtained by relating the running parameters in the MS bar renormalization scheme to observables at lower energies with full two-loop precision. The evolution is then performed in accordance with the renormalization group equations with full three-loop precision. Pure QCD corrections to the matching and running are included through four loops. We also provide a Mathematica interface for this program library. Catalogue identifier: AFAI_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AFAI_v1_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: GNU General Public License, version 3 No. of lines in distributed program, including test data, etc.: 517613 No. of bytes in distributed program, including test data, etc.: 2358729 Distribution format: tar.gz Programming language: C++. Computer: IBM PC. Operating system: Linux, Mac OS X. RAM: 1 GB Classification: 11.1. External routines: TSIL [1], OdeInt [2], boost [3] Nature of problem: The running parameters of the Standard Model renormalized in the MS bar scheme at some high renormalization scale, which is chosen by the user, are evaluated in perturbation theory as precisely as possible in two steps. First, the initial conditions at the electroweak energy scale are evaluated from the Fermi constant GF and the pole masses of the W, Z, and Higgs bosons and the bottom and top quarks including the full two-loop threshold corrections. Second, the evolution to the high energy scale is performed by numerically solving the renormalization group evolution equations through three loops. Pure QCD corrections to the matching and running are included through four loops. Solution method: Numerical integration of analytic expressions Additional comments: Available for download from URL
An introduction to the dimer model
International Nuclear Information System (INIS)
Kenyon, R.
2004-01-01
A perfect matching of a graph is a subset of edges which covers every vertex exactly once, that is, for every vertex there is exactly one edge in the set with that vertex as endpoint. The dimer model is the study of the set of perfect matchings of a (possibly infinite) graph. The most well-known example is when the graph is Z 2 , for which perfect matchings are equivalent (via a simple duality) to domino tilings, that is, tilings of the plane with 2 x 1 and 1 x 2 rectangles. In the first three sections we study domino tilings of the plane and of finite polygonal regions, or equivalently, perfect matchings on Z 2 and subgraphs of Z 2 . In the last two sections we study the FK-percolation model and the dimer model on a more general family of planar graphs
Directory of Open Access Journals (Sweden)
N. Kochi
2012-07-01
Full Text Available We have been developing the stereo-matching method and its system by digital photogrammetry using a digital camera to make 3D Measurement of various objects. We are also developing the technology to process 3D point clouds of enormous amount obtained through Terrestrial Laser Scanner (TLS. But this time, we have developed the technology to produce a Surface-Model by detecting the 3D edges on the stereo-images of digital camera. Then we arrived to register the 3D data obtained from the stereo-images and the 3D edge data detected on the 3D point-cloud of TLS, and thus succeeded to develop the new technology to fuse the 3D data of Camera and TLS. The basic idea is to take stereo-pictures by a digital camera around the areas where the scanner cannot, because of the occlusion. The camera, with the digital photogrammetry, can acquire the data of complicated and hidden areas instantly, thus shutting out the possibility of noises in a blink. The data of the camera are then integrated into the data of the scanner to produce automatically the model of great perfection. In this presentation, therefore, we will show (1 how to detect the 3D edges on the photo images and to detect from the scanner's point-cloud, (2 how to register the data of both 3D edges to produce the unified model, (3 how to assess the accuracy and the speed of analysing process, which turned out to be quite satisfactory.
Doron, J; Martinent, G
2017-09-01
Understanding more about the stress process is important for the performance of athletes during stressful situations. Grounded in Lazarus's (1991, 1999, 2000) CMRT of emotion, this study tracked longitudinally the relationships between cognitive appraisal, coping, emotions, and performance in nine elite fencers across 14 international matches (representing 619 momentary assessments) using a naturalistic, video-assisted methodology. A series of hierarchical linear modeling analyses were conducted to: (a) explore the relationships between cognitive appraisals (challenge and threat), coping strategies (task- and disengagement oriented coping), emotions (positive and negative) and objective performance; (b) ascertain whether the relationship between appraisal and emotion was mediated by coping; and (c) examine whether the relationship between appraisal and objective performance was mediated by emotion and coping. The results of the random coefficient regression models showed: (a) positive relationships between challenge appraisal, task-oriented coping, positive emotions, and performance, as well as between threat appraisal, disengagement-oriented coping and negative emotions; (b) that disengagement-oriented coping partially mediated the relationship between threat and negative emotions, whereas task-oriented coping partially mediated the relationship between challenge and positive emotions; and (c) that disengagement-oriented coping mediated the relationship between threat and performance, whereas task-oriented coping and positive emotions partially mediated the relationship between challenge and performance. As a whole, this study furthered knowledge during sport performance situations of Lazarus's (1999) claim that these psychological constructs exist within a conceptual unit. Specifically, our findings indicated that the ways these constructs are inter-related influence objective performance within competitive settings. © 2016 John Wiley & Sons A/S. Published by
History matching of transient pressure build-up in a simulation model using adjoint method
Energy Technology Data Exchange (ETDEWEB)
Ajala, I.; Haekal, Rachmat; Ganzer, L. [Technische Univ. Clausthal, Clausthal-Zellerfeld (Germany); Almuallim, H. [Firmsoft Technologies, Inc., Calgary, AB (Canada); Schulze-Riegert, R. [SPT Group GmbH, Hamburg (Germany)
2013-08-01
The aim of this work is the efficient and computer-assisted history-matching of pressure build-up and pressure derivatives by small modification to reservoir rock properties on a grid by grid level. (orig.)
Perfect extinction in subwavelength dual metallic transmitting gratings.
Estruch, Thomas; Jaeck, Julien; Pardo, Fabrice; Derelle, Sophie; Primot, Jérôme; Pelouard, Jean-Luc; Haidar, Riad
2011-08-15
We investigate the strong electromagnetic coupling that settles in dual metallic grating structures. This coupling is evidenced to lead to a perfect optical extinction in the transmission spectrum. The behavior of this perfect extinction that strongly depends on the longitudinal space and the lateral displacement between the two gratings can be explained by a simple model that describes the interference between a propagating mode and a couple of evanescent modes. The results show that the electromagnetic transmission of the structure can be tuned by controlling the position of this perfect transmission extinction and thus pave the way to new types of infrared tunable filters. © 2011 Optical Society of America
2012-01-01
Background About one-third of adults with diabetes have severe oral complications. However, limited previous research has investigated dental care utilization associated with diabetes. This project had two purposes: to develop a methodology to estimate dental care utilization using claims data and to use this methodology to compare utilization of dental care between adults with and without diabetes. Methods Data included secondary enrollment and demographic data from Washington Dental Service (WDS) and Group Health Cooperative (GH), clinical data from GH, and dental-utilization data from WDS claims during 2002–2006. Dental and medical records from WDS and GH were linked for enrolees continuously and dually insured during the study. We employed hurdle models in a quasi-experimental setting to assess differences between adults with and without diabetes in 5-year cumulative utilization of dental services. Propensity score matching adjusted for differences in baseline covariates between the two groups. Results We found that adults with diabetes had lower odds of visiting a dentist (OR = 0.74, p dental visit, diabetes patients had lower odds of receiving prophylaxes (OR = 0.77), fillings (OR = 0.80) and crowns (OR = 0.84) (p diabetes are less likely to use dental services. Those who do are less likely to use preventive care and more likely to receive periodontal care and tooth-extractions. Future research should address the possible effectiveness of additional prevention in reducing subsequent severe oral disease in patients with diabetes. PMID:22776352
Directory of Open Access Journals (Sweden)
Chaudhari Monica
2012-07-01
Full Text Available Abstract Background About one-third of adults with diabetes have severe oral complications. However, limited previous research has investigated dental care utilization associated with diabetes. This project had two purposes: to develop a methodology to estimate dental care utilization using claims data and to use this methodology to compare utilization of dental care between adults with and without diabetes. Methods Data included secondary enrollment and demographic data from Washington Dental Service (WDS and Group Health Cooperative (GH, clinical data from GH, and dental-utilization data from WDS claims during 2002–2006. Dental and medical records from WDS and GH were linked for enrolees continuously and dually insured during the study. We employed hurdle models in a quasi-experimental setting to assess differences between adults with and without diabetes in 5-year cumulative utilization of dental services. Propensity score matching adjusted for differences in baseline covariates between the two groups. Results We found that adults with diabetes had lower odds of visiting a dentist (OR = 0.74, p 0.001. Among those with a dental visit, diabetes patients had lower odds of receiving prophylaxes (OR = 0.77, fillings (OR = 0.80 and crowns (OR = 0.84 (p 0.005 for all and higher odds of receiving periodontal maintenance (OR = 1.24, non-surgical periodontal procedures (OR = 1.30, extractions (OR = 1.38 and removable prosthetics (OR = 1.36 (p Conclusions Patients with diabetes are less likely to use dental services. Those who do are less likely to use preventive care and more likely to receive periodontal care and tooth-extractions. Future research should address the possible effectiveness of additional prevention in reducing subsequent severe oral disease in patients with diabetes.
Directory of Open Access Journals (Sweden)
Michal Brylinski
2014-09-01
Full Text Available Detecting similarities between ligand binding sites in the absence of global homology between target proteins has been recognized as one of the critical components of modern drug discovery. Local binding site alignments can be constructed using sequence order-independent techniques, however, to achieve a high accuracy, many current algorithms for binding site comparison require high-quality experimental protein structures, preferably in the bound conformational state. This, in turn, complicates proteome scale applications, where only various quality structure models are available for the majority of gene products. To improve the state-of-the-art, we developed eMatchSite, a new method for constructing sequence order-independent alignments of ligand binding sites in protein models. Large-scale benchmarking calculations using adenine-binding pockets in crystal structures demonstrate that eMatchSite generates accurate alignments for almost three times more protein pairs than SOIPPA. More importantly, eMatchSite offers a high tolerance to structural distortions in ligand binding regions in protein models. For example, the percentage of correctly aligned pairs of adenine-binding sites in weakly homologous protein models is only 4-9% lower than those aligned using crystal structures. This represents a significant improvement over other algorithms, e.g. the performance of eMatchSite in recognizing similar binding sites is 6% and 13% higher than that of SiteEngine using high- and moderate-quality protein models, respectively. Constructing biologically correct alignments using predicted ligand binding sites in protein models opens up the possibility to investigate drug-protein interaction networks for complete proteomes with prospective systems-level applications in polypharmacology and rational drug repositioning. eMatchSite is freely available to the academic community as a web-server and a stand-alone software distribution at http://www.brylinski.org/ematchsite.
Liu, Min; He, Yue; Qian, Weili; Wei, Yangliu; Liu, Xiaoyan
2017-10-06
Developing algorithms for plant cell population tracking is very critical for the modeling of plant cell growth pattern and gene expression dynamics. The tracking of plant cells in microscopic image stacks is very challenging for several reasons: (1) plant cells are densely packed in a specific honeycomb structure; (2) they are frequently dividing; (3) they are imaged in different layers within 3D image stacks. Based on an existing 2D local graph matching algorithm, this paper focuses on building a 3D plant cell matching model, by exploiting the cells' 3D spatiotemporal context. Furthermore, the Interacting Multi-Model filter (IMM) is combined with the 3D local graph matching model to track the plant cell population simultaneously. Because our tracking algorithm does not require the identification of "tracking seeds", the tracking stability and efficiency are greatly enhanced. Last, the plant cell lineages are achieved by associating the cell tracklets, using a maximum-a-posteriori (MAP) method. Compared with the 2D matching method, the experimental results on multiple datasets show that our proposed approach does not only greatly improve the tracking accuracy by 18%, but also successfully tracks the plant cells located at the high curvature primordial region, which is not addressed in previous work.
Visible light broadband perfect absorbers
Energy Technology Data Exchange (ETDEWEB)
Jia, X. L.; Meng, Q. X.; Yuan, C. X.; Zhou, Z. X.; Wang, X. O., E-mail: wxo@hit.edu.cn [School of Science, Harbin Institute of Technology, Harbin 150001 (China)
2016-03-15
The visible light broadband perfect absorbers based on the silver (Ag) nano elliptical disks and holes array are studied using finite difference time domain simulations. The semiconducting indium silicon dioxide thin film is introduced as the space layer in this sandwiched structure. Utilizing the asymmetrical geometry of the structures, polarization sensitivity for transverse electric wave (TE)/transverse magnetic wave (TM) and left circular polarization wave (LCP)/right circular polarization wave (RCP) of the broadband absorption are gained. The absorbers with Ag nano disks and holes array show several peaks absorbance of 100% by numerical simulation. These simple and flexible perfect absorbers are particularly desirable for various potential applications including the solar energy absorber.
DEFF Research Database (Denmark)
Ravlo, Kristian; Chhoden, Tashi; Søndergaard, Peter
2012-01-01
Kidney transplantation from a large donor to a small recipient, as in pediatric transplantation, is associated with an increased risk of thrombosis and DGF. We established a porcine model for renal transplantation from an adult donor to a small or size-matched recipient with a high risk of DGF...... and studied GFR, RPP using MRI, and markers of kidney injury within 10 h after transplantation. After induction of BD, kidneys were removed from ∼63-kg donors and kept in cold storage for ∼22 h until transplanted into small (∼15 kg, n = 8) or size-matched (n = 8) recipients. A reduction in GFR was observed...
Records matching model for data survey on applied and experimental microbiology.
Reina, Salvatore A; Reina, Vito M; Debbia, Eugenio A
2007-01-01
Experimental microbiology yields a huge quantity of raw data which needs to be evaluated and classified in a wide variety of situation from marine research, environmental pollution and pharmacokinetics of antimicrobial agents to epidemiological clinical trials on infectious diseases. It is indispensable in all kinds of disciplines to validate, transform and correlate data clusters to demonstrate the statistical significance of results. Whether academic or biotechnological, the scientific credibility of a work is strongly affected by the statistical methods and their adequacy. For a simple univariate analysis, many commercial or open source software products are available to perform sophisticated statistics for discriminant and multi-factorial analysis, but the majority of scientists use statistics partially. This is due to the high competence level required by a multivariate approach. It is known that the choice of a test, correct distribution assumption, valid experimental design and preliminary raw data validation are prejudicial to good science. All kinds of experimentation need analytical interpretation of descriptive evidence so that a classical numerical approach is not enough when raw data are not validated or incomplete. Microbiologists always wish to quickly discriminate, or correlate, group and data clusters concerning clinical patient profiles, auditing multi-sensor derived numbers, monitoring biosphere indicators on either chemical and physical parameters or dynamics of microbe populations. Mathematical and statistical analysis is essential to distinguish phenotypes or constraints. Data are in general stored in spreadsheet and database files which change continuously depending on the data collection and scope. We here propose a Records Matching Method (RMM) suitable for any kind of cluster analysis and pattern identification which can be used for either parametric or non parametric analysis without necessarily stating the pre-process statistical
Looking beyond the perfect lens
International Nuclear Information System (INIS)
Wee, W H; Pendry, J B
2010-01-01
The holy grail of imaging is the ability to see through anything. From the conservation of energy, we can easily see that to see through a lossy material would require lenses with gain. The aim of this paper therefore is to propose a simple scheme by which we can construct a general perfect lens, with gain-one that can restore both the phases and amplitudes of near and far fields.
Chebotarev, Alexander Yu.; Grenkin, Gleb V.; Kovtanyuk, Andrey E.; Botkin, Nikolai D.; Hoffmann, Karl-Heinz
2018-04-01
The paper is concerned with a problem of diffraction type. The study starts with equations of complex (radiative and conductive) heat transfer in a multicomponent domain with Fresnel matching conditions at the interfaces. Applying the diffusion, P1, approximation yields a pair of coupled nonlinear PDEs describing the radiation intensity and temperature for each component of the domain. Matching conditions for these PDEs, imposed at the interfaces between the domain components, are derived. The unique solvability of the obtained problem is proven, and numerical experiments are conducted.
Bradley, D. B.; Irwin, J. D.
1974-01-01
A computer simulation model for a multiprocessor computer is developed that is useful for studying the problem of matching multiprocessor's memory space, memory bandwidth and numbers and speeds of processors with aggregate job set characteristics. The model assumes an input work load of a set of recurrent jobs. The model includes a feedback scheduler/allocator which attempts to improve system performance through higher memory bandwidth utilization by matching individual job requirements for space and bandwidth with space availability and estimates of bandwidth availability at the times of memory allocation. The simulation model includes provisions for specifying precedence relations among the jobs in a job set, and provisions for specifying precedence execution of TMR (Triple Modular Redundant and SIMPLEX (non redundant) jobs.
Too Much Matching: A Social Relations Model Enhancement of the Pairing Game
Eastwick, Paul W.; Buck, April A.
2014-01-01
The Pairing Game is a popular classroom demonstration that illustrates how people select romantic partners who approximate their own desirability. However, this game produces matching correlations that greatly exceed the correlations that characterize actual romantic pairings, perhaps because the game does not incorporate the social relations…
Analytical modelling of waveguide mode launchers for matched feed reflector systems
DEFF Research Database (Denmark)
Palvig, Michael Forum; Breinbjerg, Olav; Meincke, Peter
2016-01-01
Matched feed horns aim to cancel cross polarization generated in offset reflector systems. An analytical method for predicting the mode spectrum generated by inclusions in such horns, e.g. stubs and pins, is presented. The theory is based on the reciprocity theorem with the inclusions represented...
Dynamic Response-by-Response Models of Matching Behavior in Rhesus Monkeys
Lau, Brian; Glimcher, Paul W.
2005-01-01
We studied the choice behavior of 2 monkeys in a discrete-trial task with reinforcement contingencies similar to those Herrnstein (1961) used when he described the matching law. In each session, the monkeys experienced blocks of discrete trials at different relative-reinforcer frequencies or magnitudes with unsignalled transitions between the…
Directory of Open Access Journals (Sweden)
Sediasih Sediasih
2017-03-01
Full Text Available Abstrak. Hasil belajar siswa pada mata pelajaran pendidikan kewarganegaraan (PKn di SDN karyawangi 2 selama ini masih rendah. Model pembelajaran yang digunakan selama ini masih menggunakan model konvensional dan hanya guru sebagai pusat pembelajaran. Tujuan dari penelitian perbaikan pembelajaran ini untuk meningkatkan hasil belajar siswa tentang materi menjaga keutuhan negara Indonesia dengan menggunakan model make a match. Penelitian dilaksanakan dalam tiga siklus perbaikan pada menjaga keutuhan, dimana masing-masing siklus terdiri dari empat tahapan yaitu perencanaan, pelaksanaan, observasi dan refleksi. Sebagai subjek penelitian adalah siswa kelas V sebanyak 30 siswa. Dalam pengumpulan data, metode yang digunakan sebagai metode pokok adalah tes tertulis. Hasil belajar dapat menunjukkan bahwa pembelajaran menjaga keutuhan negara Indonesia mengalami peningkatan. Metode penelitian ini dengan menggunakan penelitian tindakan kelas. Dari hasil dapat disimpulkan bila penggunaan model make a match dapat meningkatkan hasil belajar siswa pada materi menjaga keutuhan negara indonesia pada mata pelajaran pendidikan kewarganegaraan di kelas 5 SDN Karyawangi 2. Kata Kunci: hasil belajar, make a match, pendidikan kewarganegaraan. Abstact. The outcomes learning of student learning on civic education subjects (Civics SDN karyawangi 2 for this is still low. The learning model is used for this are still using the conventional model and only teachers as a learning center. The purpose of this research study improvements to improve student learning outcomes of the material safeguarding the national integrity Indonesia using models make a match. Research carried out in three cycles of improvement in maintaining the integrity, in which each cycle consists of four phases: planning, implementation, observation and reflection. As research subjects are students of class V as many as 30 students. In collecting the data, the methods used as the principal method
International Nuclear Information System (INIS)
Zulkoffli, Zuliani; Bakar, Elmi Abu
2016-01-01
This paper present pose estimation relation of CAD model object and Projection Real Object (PRI). Image sequence of PRI and CAD model rotate on z axis at 10 degree interval in simulation and real scene used in this experiment. All this image is go through preprocessing stage to rescale object size and image size and transform all the image into silhouette. Correlation of CAD and PRI image is going through in this stage. Magnitude spectrum shows a reliable value in range 0.99 to 1.00 and Phase spectrum correlation shows a fluctuate graph in range 0.56 - 0.97. Euclidean distance correlation graph for CAD and PRI shows 2 zone of similar value due to almost symmetrical object shape. Processing stage of retrieval inspected PRI image in CAD database was carried out using range phase spectrum and maximum magnitude spectrum value within ±10% tolerance. Additional processing stage of retrieval inspected PRI image using Euclidean distance within ±5% tolerance also carried out. Euclidean matching shows a reliable result compared to range phase spectrum and maximum magnitude spectrum value by sacrificing more than 5 times processing time. (paper)
Critical phenomena at perfect and non-perfect surfaces
International Nuclear Information System (INIS)
Pleimling, M
2004-01-01
In the past, perfect surfaces have been shown to yield local critical behaviour that differs from bulk critical behaviour. On the other hand, surface defects, whether they are of natural origin or created artificially, are known to modify local quantities. It is therefore important to clarify whether these defects are relevant or irrelevant for the surface critical behaviour. The purpose of this review is two-fold. In the first part we summarize some of the important results on surface criticality at perfect surfaces. Special attention is thereby paid to new developments such as for example the study of the surface critical behaviour in systems with competing interactions or of surface critical dynamics. In the second part the effect of surface defects (presence of edges, steps, quenched randomness, lines of adatoms, regular geometric patterns) on local critical behaviour in semi-infinite systems and in thin films is discussed in detail. Whereas most of the defects commonly encountered are shown to be irrelevant, some notable exceptions are highlighted. It is shown furthermore that under certain circumstances non-universal local critical behaviour may be observed at surfaces. (topical review)
A foundation for flow-based matching: using temporal logic and model checking
DEFF Research Database (Denmark)
Brunel, Julien Pierre Manuel; Doligez, Damien; Hansen, René Rydhof
2009-01-01
Reasoning about program control-flow paths is an important functionality of a number of recent program matching languages and associated searching and transformation tools. Temporal logic provides a well-defined means of expressing properties of control-flow paths in programs, and indeed an exten......Reasoning about program control-flow paths is an important functionality of a number of recent program matching languages and associated searching and transformation tools. Temporal logic provides a well-defined means of expressing properties of control-flow paths in programs, and indeed...... an extension of the temporal logic CTL has been applied to the problem of specifying and verifying the transformations commonly performed by optimizing compilers. Nevertheless, in developing the Coccinelle program transformation tool for performing Linux collateral evolutions in systems code, we have found...
A Foundation for Flow-Based Program Matching Using Temporal Logic and Model Checking
DEFF Research Database (Denmark)
Brunel, Julien Pierre Manuel; Doligez, Damien; Hansen, Rene Rydhof
2008-01-01
Reasoning about program control-flow paths is an important functionality of a number of recent program matching languages and associated searching and transformation tools. Temporal logic provides a well-defined means of expressing properties of control-flow paths in programs, and indeed an exten......Reasoning about program control-flow paths is an important functionality of a number of recent program matching languages and associated searching and transformation tools. Temporal logic provides a well-defined means of expressing properties of control-flow paths in programs, and indeed...... an extension of the temporal logic CTL has been applied to the problem of specifying and verifying the transformations commonly performed by optimizing compilers. Nevertheless, in developing the Coccinelle program transformation tool for performing Linux collateral evolutions in systems code, we have found...
Niri, Mohammad Emami; Lumley, David E.
2017-10-01
Integration of 3D and time-lapse 4D seismic data into reservoir modelling and history matching processes poses a significant challenge due to the frequent mismatch between the initial reservoir model, the true reservoir geology, and the pre-production (baseline) seismic data. A fundamental step of a reservoir characterisation and performance study is the preconditioning of the initial reservoir model to equally honour both the geological knowledge and seismic data. In this paper we analyse the issues that have a significant impact on the (mis)match of the initial reservoir model with well logs and inverted 3D seismic data. These issues include the constraining methods for reservoir lithofacies modelling, the sensitivity of the results to the presence of realistic resolution and noise in the seismic data, the geostatistical modelling parameters, and the uncertainties associated with quantitative incorporation of inverted seismic data in reservoir lithofacies modelling. We demonstrate that in a geostatistical lithofacies simulation process, seismic constraining methods based on seismic litho-probability curves and seismic litho-probability cubes yield the best match to the reference model, even when realistic resolution and noise is included in the dataset. In addition, our analyses show that quantitative incorporation of inverted 3D seismic data in static reservoir modelling carries a range of uncertainties and should be cautiously applied in order to minimise the risk of misinterpretation. These uncertainties are due to the limited vertical resolution of the seismic data compared to the scale of the geological heterogeneities, the fundamental instability of the inverse problem, and the non-unique elastic properties of different lithofacies types.
Sudhir, Dass; Bandyopadhyay, M; Chakraborty, A
2016-02-01
Plasma characterization and impedance matching are an integral part of any radio frequency (RF) based plasma source. In long pulse operation, particularly in high power operation where plasma load may vary due to different reasons (e.g. pressure and power), online tuning of impedance matching circuit and remote plasma density estimation are very useful. In some cases, due to remote interfaces, radio activation and, due to maintenance issues, power probes are not allowed to be incorporated in the ion source design for plasma characterization. Therefore, for characterization and impedance matching, more remote schemes are envisaged. Two such schemes by the same authors are suggested in these regards, which are based on air core transformer model of inductive coupled plasma (ICP) [M. Bandyopadhyay et al., Nucl. Fusion 55, 033017 (2015); D. Sudhir et al., Rev. Sci. Instrum. 85, 013510 (2014)]. However, the influence of the RF field interaction with the plasma to determine its impedance, a physics code HELIC [D. Arnush, Phys. Plasmas 7, 3042 (2000)] is coupled with the transformer model. This model can be useful for both types of RF sources, i.e., ICP and helicon sources.
Generating perfect fluid spheres in general relativity
International Nuclear Information System (INIS)
Boonserm, Petarpa; Visser, Matt; Weinfurtner, Silke
2005-01-01
Ever since Karl Schwarzschild's 1916 discovery of the spacetime geometry describing the interior of a particular idealized general relativistic star--a static spherically symmetric blob of fluid with position-independent density--the general relativity community has continued to devote considerable time and energy to understanding the general-relativistic static perfect fluid sphere. Over the last 90 years a tangle of specific perfect fluid spheres has been discovered, with most of these specific examples seemingly independent from each other. To bring some order to this collection, in this article we develop several new transformation theorems that map perfect fluid spheres into perfect fluid spheres. These transformation theorems sometimes lead to unexpected connections between previously known perfect fluid spheres, sometimes lead to new previously unknown perfect fluid spheres, and in general can be used to develop a systematic way of classifying the set of all perfect fluid spheres
Ludwig, C; Grimmer, S; Seyfarth, A; Maus, H-M
2012-09-21
The spring-loaded inverted pendulum (SLIP) model is a well established model for describing bouncy gaits like human running. The notion of spring-like leg behavior has led many researchers to compute the corresponding parameters, predominantly stiffness, in various experimental setups and in various ways. However, different methods yield different results, making the comparison between studies difficult. Further, a model simulation with experimentally obtained leg parameters typically results in comparatively large differences between model and experimental center of mass trajectories. Here, we pursue the opposite approach which is calculating model parameters that allow reproduction of an experimental sequence of steps. In addition, to capture energy fluctuations, an extension of the SLIP (ESLIP) is required and presented. The excellent match of the models with the experiment validates the description of human running by the SLIP with the obtained parameters which we hence call dynamical leg parameters. Copyright © 2012 Elsevier Ltd. All rights reserved.
The pursuit of perfect packing
Weaire, Denis
2000-01-01
In 1998 Thomas Hales dramatically announced the solution of a problem that has long teased eminent mathematicians: what is the densest possible arrangement of identical spheres? The Pursuit of Perfect Packing recounts the story of this problem and many others that have to do with packing things together. The examples are taken from mathematics, physics, biology, and engineering, including the arrangement of soap bubbles in foam, atoms in a crystal, the architecture of the bee''s honeycomb, and the structure of the Giant''s Causeway. Using an informal style and with key references, the book also includes brief accounts of the lives of many of the scientists who devoted themselves to problems of packing over many centuries, together with wry comments on their efforts. It is an entertaining introduction to the field for both specialists and the more general public.
Zhang, Ke; Bonk, Curtis J.
2008-01-01
This paper critically reviews various learning preferences and human intelligence theories and models with a particular focus on the implications for online learning. It highlights a few key models, Gardner's multiple intelligences, Fleming and Mills' VARK model, Honey and Mumford's Learning Styles, and Kolb's Experiential Learning Model, and…
Electromagnetic Detection of a Perfect Carpet Cloak
Shi, Xihang; Gao, Fei; Lin, Xiao; Zhang, Baile
2015-05-01
It has been shown that a spherical invisibility cloak originally proposed by Pendry et al. can be electromagnetically detected by shooting a charged particle through it, whose underlying mechanism stems from the asymmetry of transformation optics applied to motions of photons and charges [PRL 103, 243901 (2009)]. However, the conceptual three-dimensional invisibility cloak that exactly follows specifications of transformation optics is formidably difficult to implement, while the simplified cylindrical cloak that has been experimentally realized is inherently visible. On the other hand, the recent carpet cloak model has acquired remarkable experimental development, including a recently demonstrated full-parameter carpet cloak without any approximation in the required constitutive parameters. In this paper, we numerically investigate the electromagnetic radiation from a charged particle passing through a perfect carpet cloak and propose an experimentally verifiable model to demonstrate symmetry breaking of transformation optics.
Bianchi type-I massive string magnetized barotropic perfect fluid ...
Indian Academy of Sciences (India)
Bianchi type-I massive string cosmological model for perfect ﬂuid distribution in the presence of magnetic ﬁeld is investigated in Rosen's [Gen. Relativ. Gravit. 4, 435 (1973)] bimetric theory of gravitation. To obtain the deterministic model in terms of cosmic time, we have used the condition A = ( B C ) n , where n is a constant, ...
Overemphasis on Perfectly Competitive Markets in Microeconomics Principles Textbooks
Hill, Roderick; Myatt, Anthony
2007-01-01
Microeconomic principles courses focus on perfectly competitive markets far more than other market structures. The authors examine five possible reasons for this but find none of them sufficiently compelling. They conclude that textbook authors should place more emphasis on how economists select appropriate models and test models' predictions…
Directory of Open Access Journals (Sweden)
Hao Yu
2018-01-01
Full Text Available This study introduces a data-driven modeling strategy for smart grid power quality (PQ coupling assessment based on time series pattern matching to quantify the influence of single and integrated disturbance among nodes in different pollution patterns. Periodic and random PQ patterns are constructed by using multidimensional frequency-domain decomposition for all disturbances. A multidimensional piecewise linear representation based on local extreme points is proposed to extract the patterns features of single and integrated disturbance in consideration of disturbance variation trend and severity. A feature distance of pattern (FDP is developed to implement pattern matching on univariate PQ time series (UPQTS and multivariate PQ time series (MPQTS to quantify the influence of single and integrated disturbance among nodes in the pollution patterns. Case studies on a 14-bus distribution system are performed and analyzed; the accuracy and applicability of the FDP in the smart grid PQ coupling assessment are verified by comparing with other time series pattern matching methods.
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Directory of Open Access Journals (Sweden)
Daniel Tik-Pui Fong
2012-10-01
Full Text Available Lateral ankle sprains continue to be the most common injury sustained by athletes and create an annual healthcare burden of over $4 billion in the U.S. alone. Foot inversion is suspected in these cases, but the mechanism of injury remains unclear. While kinematics and kinetics data are crucial in understanding the injury mechanisms, ligament behaviour measures – such as ligament strains – are viewed as the potential causal factors of ankle sprains. This review article demonstrates a novel methodology that integrates model matching video analyses with computational simulations in order to investigate injury-producing events for a better understanding of such injury mechanisms. In particular, ankle joint kinematics from actual injury incidents were deduced by model matching video analyses and then input into a generic computational model based on rigid bone surfaces and deformable ligaments of the ankle so as to investigate the ligament strains that accompany these sprain injuries. These techniques may have the potential for guiding ankle sprain prevention strategies and targeted rehabilitation therapies.
Langer, P.; Sepahvand, K.; Guist, C.; Bär, J.; Peplow, A.; Marburg, S.
2018-03-01
The simulation model which examines the dynamic behavior of real structures needs to address the impact of uncertainty in both geometry and material parameters. This article investigates three-dimensional finite element models for structural dynamics problems with respect to both model and parameter uncertainties. The parameter uncertainties are determined via laboratory measurements on several beam-like samples. The parameters are then considered as random variables to the finite element model for exploring the uncertainty effects on the quality of the model outputs, i.e. natural frequencies. The accuracy of the output predictions from the model is compared with the experimental results. To this end, the non-contact experimental modal analysis is conducted to identify the natural frequency of the samples. The results show a good agreement compared with experimental data. Furthermore, it is demonstrated that geometrical uncertainties have more influence on the natural frequencies compared to material parameters and material uncertainties are about two times higher than geometrical uncertainties. This gives valuable insights for improving the finite element model due to various parameter ranges required in a modeling process involving uncertainty.
Korhonen, J.M.; Kasmire, J.
2012-01-01
Computer simulations are increasingly used to study the development, adoption, and evolution of technologies. However, existing models suffer from various drawbacks that may not be easily corrected, among them lack of internal structure in technologies, static environments and practical difficulties
Matching allele dynamics and coevolution in a minimal predator-prey replicator model
Energy Technology Data Exchange (ETDEWEB)
Sardanyes, Josep [Complex Systems Lab (ICREA-UPF), Barcelona Biomedical Research Park (PRBB-GRIB), Dr. Aiguader 88, 08003 Barcelona (Spain)], E-mail: josep.sardanes@upf.edu; Sole, Ricard V. [Complex Systems Lab (ICREA-UPF), Barcelona Biomedical Research Park (PRBB-GRIB), Dr. Aiguader 88, 08003 Barcelona (Spain); Santa Fe Institute, 1399 Hyde Park Road, Santa Fe, NM 87501 (United States)
2008-01-21
A minimal Lotka-Volterra type predator-prey model describing coevolutionary traits among entities with a strength of interaction influenced by a pair of haploid diallelic loci is studied with a deterministic time continuous model. We show a Hopf bifurcation governing the transition from evolutionary stasis to periodic Red Queen dynamics. If predator genotypes differ in their predation efficiency the more efficient genotype asymptotically achieves lower stationary concentrations.
Efendiev, Y.
2009-11-01
The Markov chain Monte Carlo (MCMC) is a rigorous sampling method to quantify uncertainty in subsurface characterization. However, the MCMC usually requires many flow and transport simulations in evaluating the posterior distribution and can be computationally expensive for fine-scale geological models. We propose a methodology that combines coarse- and fine-scale information to improve the efficiency of MCMC methods. The proposed method employs off-line computations for modeling the relation between coarse- and fine-scale error responses. This relation is modeled using nonlinear functions with prescribed error precisions which are used in efficient sampling within the MCMC framework. We propose a two-stage MCMC where inexpensive coarse-scale simulations are performed to determine whether or not to run the fine-scale (resolved) simulations. The latter is determined on the basis of a statistical model developed off line. The proposed method is an extension of the approaches considered earlier where linear relations are used for modeling the response between coarse-scale and fine-scale models. The approach considered here does not rely on the proximity of approximate and resolved models and can employ much coarser and more inexpensive models to guide the fine-scale simulations. Numerical results for three-phase flow and transport demonstrate the advantages, efficiency, and utility of the method for uncertainty assessment in the history matching. Copyright 2009 by the American Geophysical Union.
Do projections from bioclimatic envelope models and climate change metrics match?
DEFF Research Database (Denmark)
Garcia, Raquel A.; Cabeza, Mar; Altwegg, Res
2016-01-01
in the position of climatically suitable areas (models) greater for species in grid cells with climates projected to move farther in space (metrics)? Results: The changes in climatic suitability projected by the bioclimatic envelope models covaried with the climatic changes measured with the metrics. Agreement......Aim: Bioclimatic envelope models are widely used to describe changes in climatically suitable areas for species under future climate scenarios. Climate change metrics are applied independently of species data to characterize the spatio-temporal dynamics of climate, and have also been used...... as indicators of the exposure of species to climate change. Here, we investigate whether these two approaches provide qualitatively similar indications about where biodiversity is potentially most exposed to climate change. Location: Sub-Saharan Africa. Methods: We compared a range of climate change metrics...
Directory of Open Access Journals (Sweden)
Udin Cahya Ari Prastya
2016-08-01
Full Text Available This research is conducted due to the problems faced by the fifth graders of Ampelgading 01 Public Elementary School. They find difficulties in understanding social science subject, indicated by students’ learning outcomes. Only 5% students of class pass the Minimum Passing Criteria of 70. Teacher-centered learning decreases the interaction between teachers and students and students with students, which related to the development of social skills such. Therefore, interactive learning model is needed to build good classroom atmosphere and improve students’ interactions. One model of interactive learning is a Make a Match.This research used quantitative and quasi-experiment methods, Quasi-experimental design used is nonequivalent control group design, using independent t-test assisted with SPSS 16 software for data analysis.The research result presents following the treatment in experimental class using cooperative teaching model ‘Make a Match’ using slide share, average grade of posttest obtained from control group is 66,15 while the experimental class gained the average of 75,18; control class obtained social skills scores with the average of 45 and 61 for experimental class. t test result indicates the cognitive learning measured from gain score of pretest and posttest have significant value of 0.000 and social skills shows significant value of 0.000. It is known that 0.000> 0.05, indicates that is related to the effect of cooperative teaching model ‘Make a Match’ using slide share to the social science cognitive and social skill. Pelaksanaan penelitian ini dikarenakan adanya masalah yang dihadapi oleh siswa kelas V di SDN Ampelgading 01. Meraka merasa kesulitas dalam memahami materi mata pelajaran IPS, hal ini dibuktikan dengan nilai hasil belajar siswa yang mendapatkan nilai di atas KKM dengan nilai KKM 70 hanya 5% dari jumlah total keseluruan siswa. Pembelajaran guru yang bersifat aksi menimbulkan tidak adanya interaksi antara
Directory of Open Access Journals (Sweden)
Poddubny Vladimir
2017-01-01
Full Text Available As the title implies the article describes how to optimize the construction of a combined cutting tool on the example of developed design of the face milling cutter with regulable rigidity of damping elements in order to improve the vibration resistance of the cutting process. RecurDyn is proposed, which is widely used for creating models of different mechanical systems, their analysis and optimization of construction, uses the ideology of visual object-oriented programming and computer research of volume solid-state models. Much attention is given to the description of the mechanical and mathematical model of the face milling cutter in RecurDyn and the results of mathematical modeling of the face milling cutter with damping elements, consisting of individual elements, with the possibility of program controlling its operation in the process of cutting. The applying of RecurDyn made it possible to carry out a complex assessment of influence of separate elements of a design of the combined cutting tool on quantitative and qualitative parameters of milling process and to define optimal values of the input and output parameters of technological process of machining for various damping elements.
Reflection of plane waves in an initially stressed perfectly ...
Indian Academy of Sciences (India)
stress and magnetic field on the reflection coef- ficients and energy ratios of reflected waves in a perfectly conducting initially stressed transversely isotropic elastic solid half-space. The present work is supposed to be useful in further studies of wave propagation in the more realistic models which have been extensively ...
Robust Secure Authentication and Data Storage with Perfect Secrecy
Directory of Open Access Journals (Sweden)
Sebastian Baur
2018-04-01
Full Text Available We consider an authentication process that makes use of biometric data or the output of a physical unclonable function (PUF, respectively, from an information theoretical point of view. We analyse different definitions of achievability for the authentication model. For the secrecy of the key generated for authentication, these definitions differ in their requirements. In the first work on PUF based authentication, weak secrecy has been used and the corresponding capacity regions have been characterized. The disadvantages of weak secrecy are well known. The ultimate performance criteria for the key are perfect secrecy together with uniform distribution of the key. We derive the corresponding capacity region. We show that, for perfect secrecy and uniform distribution of the key, we can achieve the same rates as for weak secrecy together with a weaker requirement on the distribution of the key. In the classical works on PUF based authentication, it is assumed that the source statistics are known perfectly. This requirement is rarely met in applications. That is why the model is generalized to a compound model, taking into account source uncertainty. We also derive the capacity region for the compound model requiring perfect secrecy. Additionally, we consider results for secure storage using a biometric or PUF source that follow directly from the results for authentication. We also generalize known results for this problem by weakening the assumption concerning the distribution of the data that shall be stored. This allows us to combine source compression and secure storage.
Decentralized trade with bargaining and voluntary matching
DEFF Research Database (Denmark)
Tranæs, Torben; Sloth, Birgitte; Hendon, Ebbe
1994-01-01
Rubinstein and Wolinsky (1990) study a market with one seller, two buyers, and voluntary matching. Both the competitive outcomepc and the bilateral bargaining outcomepb are possible in subgame perfect equilibrium. We consider two variations. First, if there is a cost larger thanpc−pc to the seller...
Matsumoto, Atsushi; Miyazaki, Naoyuki; Takagi, Junichi; Iwasaki, Kenji
2017-03-23
In this study, we develop an approach termed "2D hybrid analysis" for building atomic models by image matching from electron microscopy (EM) images of biological molecules. The key advantage is that it is applicable to flexible molecules, which are difficult to analyze by 3DEM approach. In the proposed approach, first, a lot of atomic models with different conformations are built by computer simulation. Then, simulated EM images are built from each atomic model. Finally, they are compared with the experimental EM image. Two kinds of models are used as simulated EM images: the negative stain model and the simple projection model. Although the former is more realistic, the latter is adopted to perform faster computations. The use of the negative stain model enables decomposition of the averaged EM images into multiple projection images, each of which originated from a different conformation or orientation. We apply this approach to the EM images of integrin to obtain the distribution of the conformations, from which the pathway of the conformational change of the protein is deduced.
The influence of geological data on the reservoir modelling and history matching process
De Jager, G.
2012-01-01
For efficient production of hydrocarbons from subsurface reservoirs it is important to understand the spatial properties of the reservoir. As there is almost always too little information on the reservoir to build a representative model directly, other techniques have been developed for generating
Directory of Open Access Journals (Sweden)
Ke Zhang
2009-03-01
Full Text Available This paper critically reviews various learning preferences and human intelligence theories and models with a particular focus on the implications for online learning. It highlights a few key models, Gardner’s multiple intelligences, Fleming and Mills’ VARK model, Honey and Mumford’s Learning Styles, and Kolb’s Experiential Learning Model, and attempts to link them to trends and opportunities in online learning with emerging technologies. By intersecting such models with online technologies, it offers instructors and instructional designers across educational sectors and situations new ways to think about addressing diverse learner needs, backgrounds, and expectations. Learning technologies are important for effective teaching, as are theories and models and theories of learning. We argue that more immense power can be derived from connections between the theories, models and learning technologies. Résumé : Cet article passe en revue de manière critique les divers modèles et théories sur les préférences d’apprentissage et l’intelligence humaine, avec un accent particulier sur les implications qui en découlent pour l’apprentissage en ligne. L’article présente quelques-uns des principaux modèles (les intelligences multiples de Gardner, le modèle VAK de Fleming et Mills, les styles d’apprentissage de Honey et Mumford et le modèle d’apprentissage expérientiel de Kolb et tente de les relier à des tendances et occasions d’apprentissage en ligne qui utilisent les nouvelles technologies. En croisant ces modèles avec les technologies Web, les instructeurs et concepteurs pédagogiques dans les secteurs de l’éducation ou en situation éducationnelle se voient offrir de nouvelles façons de tenir compte des divers besoins, horizons et attentes des apprenants. Les technologies d’apprentissage sont importantes pour un enseignement efficace, tout comme les théories et les modèles d’apprentissage. Nous sommes d
Directory of Open Access Journals (Sweden)
Jaejun Kim
2017-04-01
Full Text Available This paper presents a fast, reliable multi-objective history-matching method based on proxy modeling to forecast the production performances of shale gas reservoirs for which all available post-hydraulic-fracturing production data, i.e., the daily gas rate and cumulative-production volume until the given date, are honored. The developed workflow consists of distance-based generalized sensitivity analysis (DGSA to determine the spatiotemporal-parameter significance, fast marching method (FMM as a proxy model, and a multi-objective evolutionary algorithm to integrate the dynamic data. The model validation confirms that the FMM is a sound surrogate model working within an error of approximately 2% for the estimated ultimate recovery (EUR, and it is 11 times faster than a full-reservoir simulation. The predictive accuracy on future production after matching 1.5-year production histories is assessed to examine the applicability of the proposed method. The DGSA determines the effective parameters with respect to the gas rate and the cumulative volume, including fracture permeability, fracture half-length, enhanced permeability in the stimulated reservoir volume, and average post-fracturing porosity. A comparison of the prediction accuracy for single-objective optimization shows that the proposed method accurately estimates the recoverable volume as well as the production profiles to within an error of 0.5%, while the single-objective consideration reveals the scale-dependency problem with lesser accuracy. The results of this study are useful to overcome the time-consuming effort of using a multi-objective evolutionary algorithm and full-scale reservoir simulation as well as to conduct a more-realistic prediction of the shale gas reserves and the corresponding production performances.
DEFF Research Database (Denmark)
Bernus, Peter; Baltrusch, Rob; Vesterager, Johan
2002-01-01
The Globemen Consortium has developed the virtual enterprise reference architecture and methodology (VERAM), based on GERAM and developed reference models for virtual enterprise management and joint mission delivery. The planned virtual enterprise capability includes the areas of sales...... and marketing, global engineering, and customer relationship management. The reference models are the basis for the development of ICT infrastructure requirements. These in turn can be used for ICT infrastructure specification (sometimes referred to as 'ICT architecture').Part of the ICT architecture...... is industry-wide, part of it is industry-specific and a part is specific to the domains of the joint activity that characterises the given Virtual Enterprise Network at hand. The article advocates a step by step approach to building virtual enterprise capability....
The Additive Risk Model for Estimation of Effect of Haplotype Match in BMT Studies
DEFF Research Database (Denmark)
Scheike, Thomas; Martinussen, T; Zhang, MJ
2011-01-01
leads to a missing data problem. We show how Aalen's additive risk model can be applied in this setting with the benefit that the time-varying haplomatch effect can be easily studied. This problem has not been considered before, and the standard approach where one would use the expected-maximization (EM......) algorithm cannot be applied for this model because the likelihood is hard to evaluate without additional assumptions. We suggest an approach based on multivariate estimating equations that are solved using a recursive structure. This approach leads to an estimator where the large sample properties can...... be developed using product-integration theory. Small sample properties are investigated using simulations in a setting that mimics the motivating haplomatch problem....
When growth and photosynthesis don't match: implications for carbon balance models
Medlyn, B.; Mahmud, K.; Duursma, R.; Pfautsch, S.; Campany, C.
2017-12-01
Most models of terrestrial plant growth are based on the principle of carbon balance: that growth can be predicted from net uptake of carbon via photosynthesis. A key criticism leveled at these models by plant physiologists is that there are many circumstances in which plant growth appears to be independent of photosynthesis: for example, during the onset of drought, or with rising atmospheric CO2 concentration. A crucial problem for terrestrial carbon cycle models is to develop better representations of plant carbon balance when there is a mismatch between growth and photosynthesis. Here we present two studies providing insight into this mismatch. In the first, effects of root restriction on plant growth were examined by comparing Eucalyptus tereticornis seedlings growing in containers of varying sizes with freely-rooted seedlings. Root restriction caused a reduction in photosynthesis, but this reduction was insufficient to explain the even larger reduction observed in growth. We applied data assimilation to a simple carbon balance model to quantify the response of carbon balance as a whole in this experiment. We inferred that, in addition to photosynthesis, there are significant effects of root restriction on growth respiration, carbon allocation, and carbohydrate utilization. The second study was carried out at the EucFACE Free-Air CO2 Enrichment experiment. At this experiment, photosynthesis of the overstorey trees is increased with enriched CO2, but there is no significant effect on above-ground productivity. These mature trees have reached their maximum height but are at significant risk of canopy loss through disturbance, and we hypothesized that additional carbon taken up through photosynthesis is preferentially allocated to storage rather than growth. We tested this hypothesis by measuring stemwood non-structural carbohydrates (NSC) during a psyllid outbreak that completely defoliated the canopy in 2015. There was a significant drawdown of NSC during
Optimal Packed String Matching
DEFF Research Database (Denmark)
Ben-Kiki, Oren; Bille, Philip; Breslauer, Dany
2011-01-01
In the packed string matching problem, each machine word accommodates – characters, thus an n-character text occupies n/– memory words. We extend the Crochemore-Perrin constantspace O(n)-time string matching algorithm to run in optimal O(n/–) time and even in real-time, achieving a factor – speedup...... over traditional algorithms that examine each character individually. Our solution can be efficiently implemented, unlike prior theoretical packed string matching work. We adapt the standard RAM model and only use its AC0 instructions (i.e., no multiplication) plus two specialized AC0 packed string...
International Nuclear Information System (INIS)
Higashi, Masahiko; Yamamura, Norio; Nakajima, Hisao; Abe, Takuya
1993-01-01
The present not is concerned with how the ecosystem maintains its energy and matter processes, and how those processes change throughout ecological and geological time, or how the constituent biota of an ecosystem maintain their life, and how ecological (species) succession and biological evolution proceed within an ecosystem. To advance further Tansky's (1976) approach to ecosystem organization, which investigated the characteristic properties of the developmental process of a model ecosystem, by applying Margalef's (1968) maximum maturity principle to derive its long term change, we seek a course for deriving the macroscopic trends along the organization process of an ecosystem as a consequence of the interactions among its biotic components and their modification of ecological traits. Using a simple ecosystem model consisting of four aggregated components (open-quotes compartmentsclose quotes) connected by nutrient flows, we investigate how a change in the value of a parameter alters the network pattern of flows and stocks, even causing a change in the value of another parameter, which in turn brings about further change in the network pattern and values of some (possible original) parameters. The continuation of this chain reaction involving feedbacks constitutes a possible mechanism for the open-quotes coevolutionclose quotes or open-quotes matchingclose quotes among flows, stocks, and parameters
Luo, Lin; Shen, Hui-Liang; Shao, Si-Jie; Xin, John
2015-08-01
The state-of-the-art multispectral imaging system can directly acquire the reflectance of a single strand of yarn that is impossible for traditional spectrophotometers. Instead, the spectrophotometric reflectance of a yarn winding, which is constituted by yarns wound on a background card, is regarded as the yarn reflectance in textile. While multispectral imaging systems and spectrophotometers can be separately used to acquire the reflectance of a single strand of yarn and corresponding yarn winding, the quantitative relationship between them is not yet known. In this paper, the relationship is established based on models that describe the spectral response of a spectrophotometer to a yarn winding and that of a multispectral imaging system to a single strand of yarn. The reflectance matching function from a single strand of yarn to corresponding yarn winding is derived to be a second degree polynomial function, which coefficients are the solutions of a constrained nonlinear optimization problem. Experiments on 100 pairs of samples show that the proposed approach can reduce the color difference between yarn windings and single strands of yarns from 2.449 to 1.082 CIEDE2000 units. The coefficients of the optimal reflection matching function imply that the reflectance of a yarn winding measured by a spectrophotometer consists of not only the intrinsic reflectance of yarn but also the nonignorable interreflection component between yarns.
Directory of Open Access Journals (Sweden)
Moedjiono Moedjiono
2016-11-01
Full Text Available In the field of services, customer satisfaction is a very important factor and determine the success of an enterprise. In the field of outsourcing, customer satisfaction indicator is the labor required delivery in a timely manner and has a level of quality in accordance with the terms proposed by the customer. To provide the best talent to customers, team recruitment and selection must perform a series of tests with a variety of methods to match the criteria of office given by the user with the criteria owned candidates and in order to support growth in graduation rates force a partner at the stage of user approval. For this purpose, the authors conducted a study with the method of observation, interviews, document reviews the candidate recruitment process, so as to provide recommendations for candidates with the highest quality delivery to the user at the stage of approval. The author put forward a model of decision support that is supported by the method of profile matching and Analytical Hierarchy Process (AHP in problem solving. The final results of this study can be used to support a decision in order to improve the effectiveness of the delivery of quality candidates, increase customer satisfaction, lower costs and improve gross operational margin of the company.
Directory of Open Access Journals (Sweden)
Benn eMacdonald
2015-11-01
Full Text Available Parameter inference in mathematical models of biological pathways, expressed as coupled ordinary differential equations (ODEs, is a challenging problem in contemporary systems biology. Conventional methods involve repeatedly solving the ODEs by numerical integration, which is computationally onerous and does not scale up to complex systems. Aimed at reducing the computational costs, new concepts based on gradient matching have recently been proposed in the computational statistics and machine learning literature. In a preliminary smoothing step, the time series data are interpolated; then, in a second step, the parameters of the ODEs are optimised so as to minimise some metric measuring the difference between the slopes of the tangents to the interpolants, and the time derivatives from the ODEs. In this way, the ODEs never have to be solved explicitly. This review provides a concise methodological overview of the current state-of-the-art methods for gradient matching in ODEs, followed by an empirical comparative evaluation based on a set of widely used and representative benchmark data.
Edwardson, Matthew A; Wang, Ximing; Liu, Brent; Ding, Li; Lane, Christianne J; Park, Caron; Nelsen, Monica A; Jones, Theresa A; Wolf, Steven L; Winstein, Carolee J; Dromerick, Alexander W
2017-06-01
Stroke patients with mild-moderate upper extremity motor impairments and minimal sensory and cognitive deficits provide a useful model to study recovery and improve rehabilitation. Laboratory-based investigators use lesioning techniques for similar goals. To determine whether stroke lesions in an upper extremity rehabilitation trial cohort match lesions from the preclinical stroke recovery models used to drive translational research. Clinical neuroimages from 297 participants enrolled in the Interdisciplinary Comprehensive Arm Rehabilitation Evaluation (ICARE) study were reviewed. Images were characterized based on lesion type (ischemic or hemorrhagic), volume, vascular territory, depth (cortical gray matter, cortical white matter, subcortical), old strokes, and leukoaraiosis. Lesions were compared with those of preclinical stroke models commonly used to study upper limb recovery. Among the ischemic stroke participants, median infarct volume was 1.8 mL, with most lesions confined to subcortical structures (61%) including the anterior choroidal artery territory (30%) and the pons (23%). Of ICARE participants, stroke patients, but they represent a clinically and scientifically important subgroup. Compared with lesions in general stroke populations and widely studied animal models of recovery, ICARE participants had smaller, more subcortically based strokes. Improved preclinical-clinical translational efforts may require better alignment of lesions between preclinical and human stroke recovery models.
Multi-channel coherent perfect absorbers
Bai, Ping
2016-05-18
The absorption efficiency of a coherent perfect absorber usually depends on the phase coherence of the incident waves on the surfaces. Here, we present a scheme to create a multi-channel coherent perfect absorber in which the constraint of phase coherence is loosened. The scheme has a multi-layer structure such that incident waves in different channels with different angular momenta can be simultaneously and perfectly absorbed. This absorber is robust in achieving high absorption efficiency even if the incident waves become "incoherent" and possess "random" wave fronts. Our work demonstrates a unique approach to designing highly efficient metamaterial absorbers. © CopyrightEPLA, 2016.
On 4-critical t-perfect graphs
Benchetrit, Yohann
2016-01-01
It is an open question whether the chromatic number of $t$-perfect graphs is bounded by a constant. The largest known value for this parameter is 4, and the only example of a 4-critical $t$-perfect graph, due to Laurent and Seymour, is the complement of the line graph of the prism $\\Pi$ (a graph is 4-critical if it has chromatic number 4 and all its proper induced subgraphs are 3-colorable). In this paper, we show a new example of a 4-critical $t$-perfect graph: the complement of the line gra...
Elsheikh, Ahmed H.
2013-06-01
We introduce a nonlinear orthogonal matching pursuit (NOMP) for sparse calibration of subsurface flow models. Sparse calibration is a challenging problem as the unknowns are both the non-zero components of the solution and their associated weights. NOMP is a greedy algorithm that discovers at each iteration the most correlated basis function with the residual from a large pool of basis functions. The discovered basis (aka support) is augmented across the nonlinear iterations. Once a set of basis functions are selected, the solution is obtained by applying Tikhonov regularization. The proposed algorithm relies on stochastically approximated gradient using an iterative stochastic ensemble method (ISEM). In the current study, the search space is parameterized using an overcomplete dictionary of basis functions built using the K-SVD algorithm. The proposed algorithm is the first ensemble based algorithm that tackels the sparse nonlinear parameter estimation problem. © 2013 Elsevier Ltd.
Zhou, Niyun; Wang, Hongwei; Wang, Jiawei
2017-06-01
The resolution of electron-potential maps in single-particle cryo-electron microscopy (cryoEM) is approaching atomic or near- atomic resolution. However, no program currently exists for de novo cryoEM model building at resolutions exceeding beyond 3.5 Å. Here, we present a program, EMBuilder, based on template matching, to generate cryoEM models at high resolution. The program identifies features in both secondary-structure and Cα stages. In the secondary structure stage, helices and strands are identified with pre-computed templates, and the voxel size of the entire map is then refined to account for microscopic magnification errors. The identified secondary structures are then extended from both ends in the Cα stage via a log-likelihood (LLK) target function, and if possible, the side chains are also assigned. This program can build models of large proteins (~1 MDa) in a reasonable amount of time (~1 day) and thus has the potential to greatly decrease the manual workload required for model building of high-resolution cryoEM maps.
Gálos, Borbála; Ostler, Wolf-Uwe; Csáki, Péter; Bidló, András; Panferov, Oleg
2016-04-01
agriculture a questionnaire has been carried out among 180 farms of different sizes and specializations (mostly arable farming and viniculture) in Reinland-Palatine, Germany. The results show that almost all farmers use the weather information daily and are in need of weather forecast. More than a half requires also the forecast on extreme events. However the farmers require more qualitative (e.g. temperature coarser than 1°C) than high-precision quantitative information in short and medium-term forecasts. Forestry requires long-term (30-100 years) climate projections. For the assessment of climate change impacts on forest distribution, production and tree species selection, monthly temperature means and precipitation sums are sufficient. Based on the results of regional climate models it will be shown how the bias, the spread and spatial resolution of the simulation results are affecting the accuracy of impact assessments. Our analyses can help to fill the gap between climate services and the needs of impact researchers and end users in agriculture and forestry. User-relevant climate information can contribute to appropriate adaptation support services and management options in the two sectors. Keywords: regional climate projections, climate impact assessment, agriculture, forestry, adaptation support, accuracy of climate information Funding: The research is supported by the "Agroclimate-2" (VKSZ_12-1-2013-0034) joint EU-national research project.
Plasmonic titanium nitride nanostructures for perfect absorbers
DEFF Research Database (Denmark)
Guler, Urcan; Li, Wen-Wei; Kinsey, Nathaniel
2013-01-01
We propose a metamaterial based perfect absorber in the visible region, and investigate the performance of titanium nitride as an alternative plasmonic material. Numerical and experimental results reveal that titanium nitride performs better than gold as a plasmonic absorbing material...
Optically Modulated Multiband Terahertz Perfect Absorber
DEFF Research Database (Denmark)
Seren, Huseyin R.; Keiser, George R.; Cao, Lingyue
2014-01-01
response of resonant metamaterials continues to be a challengingendeavor. Resonant perfect absorbers have flourished as one of the mostpromising metamaterial devices with applications ranging from power har-vesting to terahertz imaging. Here, an optically modulated resonant perfectabsorber is presented...
Matchings with Externalities and Attitudes
DEFF Research Database (Denmark)
Branzei, Simina; Michalak, Tomasz; Rahwan, Talal
2013-01-01
Two-sided matchings are an important theoretical tool used to model markets and social interactions. In many real-life problems the utility of an agent is influenced not only by their own choices, but also by the choices that other agents make. Such an influence is called an externality. Whereas...... fully expressive representations of externalities in matchings require exponential space, in this paper we propose a compact model of externalities, in which the influence of a match on each agent is computed additively. Under this framework, we analyze many-to-many matchings and one-to-one matchings...
Neumann, Rebecca B; Cardon, Zoe G; Teshera-Levye, Jennifer; Rockwell, Fulton E; Zwieniecki, Maciej A; Holbrook, N Michele
2014-04-01
The movement of water from moist to dry soil layers through the root systems of plants, referred to as hydraulic redistribution (HR), occurs throughout the world and is thought to influence carbon and water budgets and ecosystem functioning. The realized hydrologic, biogeochemical and ecological consequences of HR depend on the amount of redistributed water, whereas the ability to assess these impacts requires models that correctly capture HR magnitude and timing. Using several soil types and two ecotypes of sunflower (Helianthus annuus L.) in split-pot experiments, we examined how well the widely used HR modelling formulation developed by Ryel et al. matched experimental determination of HR across a range of water potential driving gradients. H. annuus carries out extensive night-time transpiration, and although over the last decade it has become more widely recognized that night-time transpiration occurs in multiple species and many ecosystems, the original Ryel et al. formulation does not include the effect of night-time transpiration on HR. We developed and added a representation of night-time transpiration into the formulation, and only then was the model able to capture the dynamics and magnitude of HR we observed as soils dried and night-time stomatal behaviour changed, both influencing HR. © 2013 John Wiley & Sons Ltd.
Cai, Jiji; Jung, Cheolkon
2017-09-01
We propose image-guided depth propagation for two-dimensional (2-D)-to-three-dimensional (3-D) video conversion using superpixel matching and the adaptive autoregressive (AR) model. We adopt key frame-based depth propagation that propagates the depth map in the key frame to nonkey frames. Moreover, we use the adaptive AR model for depth refinement to penalize depth-color inconsistency. First, we perform superpixel matching to estimate motion vectors at the superpixel level instead of block matching based on the fixed block size. Then, we conduct depth compensation based on motion vectors to generate the depth map in the nonkey frame. However, the size of two superpixels is not exactly the same due to the segment-based matching, which causes matching errors in the compensated depth map. Thus, we introduce an adaptive image-guided AR model to minimize matching errors and produce the final depth map by minimizing AR prediction errors. Finally, we employ depth-image-based rendering to generate stereoscopic views from 2-D videos and their depth maps. Experimental results demonstrate that the proposed method successfully performs depth propagation and produces high-quality depth maps for 2-D-to-3-D video conversion.
Matching of equivalent field regions
DEFF Research Database (Denmark)
Appel-Hansen, Jørgen; Rengarajan, S.B.
2005-01-01
In aperture problems, integral equations for equivalent currents are often found by enforcing matching of equivalent fields. The enforcement is made in the aperture surface region adjoining the two volumes on each side of the aperture. In the case of an aperture in a planar perfectly conducting...... screen, having the same homogeneous medium on both sides and an impressed current on one aide, an alternative procedure is relevant. We make use of the fact that in the aperture the tangential component of the magnetic field due to the induced currents in the screen is zero. The use of such a procedure...... shows that equivalent currents can be found by a consideration of only one of the two volumes into which the aperture plane divides the space. Furthermore, from a consideration of an automatic matching at the aperture, additional information about tangential as well as normal field components...
Matthews, A P; Garenne, M L
2013-09-01
The matching algorithm in a dynamic marriage market model is described in this first of two companion papers. Iterative Proportional Fitting is used to find a marriage function (an age distribution of new marriages for both sexes), in a stable reference population, that is consistent with the one-sex age distributions of new marriages, and includes age preference. The one-sex age distributions (which are the marginals of the two-sex distribution) are based on the Picrate model, and age preference on a normal distribution, both of which may be adjusted by choice of parameter values. For a population that is perturbed from the reference state, the total number of new marriages is found as the harmonic mean of target totals for men and women obtained by applying reference population marriage rates to the perturbed population. The marriage function uses the age preference function, assumed to be the same for the reference and the perturbed populations, to distribute the total number of new marriages. The marriage function also has an availability factor that varies as the population changes with time, where availability depends on the supply of unmarried men and women. To simplify exposition, only first marriage is treated, and the algorithm is illustrated by application to Zambia. In the second paper, remarriage and dissolution are included. Copyright © 2013 Elsevier Inc. All rights reserved.
Tierney, Gregory J; Joodaki, Hamed; Krosshaug, Tron; Forman, Jason L; Crandall, Jeff R; Simms, Ciaran K
2018-03-01
Player-to-player contact inherent in many unhelmeted sports means that head impacts are a frequent occurrence. Model-Based Image-Matching (MBIM) provides a technique for the assessment of three-dimensional linear and rotational motion patterns from multiple camera views of a head impact event, but the accuracy is unknown for this application. The goal of this study is to assess the accuracy of the MBIM method relative to reflective marker-based motion analysis data for estimating six degree of freedom head displacements and velocities in a staged pedestrian impact scenario at 40 km/h. Results showed RMS error was under 20 mm for all linear head displacements and 0.01-0.04 rad for head rotations. For velocities, the MBIM method yielded RMS errors between 0.42 and 1.29 m/s for head linear velocities and 3.53-5.38 rad/s for angular velocities. This method is thus beneficial as a tool to directly measure six degree of freedom head positional data from video of sporting head impacts, but velocity data is less reliable. MBIM data, combined in future with velocity/acceleration data from wearable sensors could be used to provide input conditions and evaluate the outputs of multibody and finite element head models for brain injury assessment of sporting head impacts.
DEFF Research Database (Denmark)
Hartelius, Karsten; Carstensen, Jens Michael
2003-01-01
A method for locating distorted grid structures in images is presented. The method is based on the theories of template matching and Bayesian image restoration. The grid is modeled as a deformable template. Prior knowledge of the grid is described through a Markov random field (MRF) model which...... represents the spatial coordinates of the grid nodes. Knowledge of how grid nodes are depicted in the observed image is described through the observation model. The prior consists of a node prior and an arc (edge) prior, both modeled as Gaussian MRFs. The node prior models variations in the positions of grid...... nodes and the arc prior models variations in row and column spacing across the grid. Grid matching is done by placing an initial rough grid over the image and applying an ensemble annealing scheme to maximize the posterior distribution of the grid. The method can be applied to noisy images with missing...
Indian Academy of Sciences (India)
Nordström exterior spacetime. The matching of nonstatic charged perfect fluid spheres to the Reissner–. Nordström exterior is restricted by the Bianchi identities as shown by Mahomed et al [1]. Static exact solutions may be used to model the interior ...
Approaches for Stereo Matching
Directory of Open Access Journals (Sweden)
Takouhi Ozanian
1995-04-01
Full Text Available This review focuses on the last decade's development of the computational stereopsis for recovering three-dimensional information. The main components of the stereo analysis are exposed: image acquisition and camera modeling, feature selection, feature matching and disparity interpretation. A brief survey is given of the well known feature selection approaches and the estimation parameters for this selection are mentioned. The difficulties in identifying correspondent locations in the two images are explained. Methods as to how effectively to constrain the search for correct solution of the correspondence problem are discussed, as are strategies for the whole matching process. Reasons for the occurrence of matching errors are considered. Some recently proposed approaches, employing new ideas in the modeling of stereo matching in terms of energy minimization, are described. Acknowledging the importance of computation time for real-time applications, special attention is paid to parallelism as a way to achieve the required level of performance. The development of trinocular stereo analysis as an alternative to the conventional binocular one, is described. Finally a classification based on the test images for verification of the stereo matching algorithms, is supplied.
Directory of Open Access Journals (Sweden)
Simon Fong
2012-01-01
Full Text Available Many forms of biometrics have been proposed and studied for biometrics authentication. Recently researchers are looking into longitudinal pattern matching that based on more than just a singular biometrics; data from user’s activities are used to characterise the identity of a user. In this paper we advocate a novel type of authentication by using a user’s medical history which can be electronically stored in a biometric security card. This is a sequel paper from our previous work about defining abstract format of medical data to be queried and tested upon authentication. The challenge to overcome is preserving the user’s privacy by choosing only the useful features from the medical data for use in authentication. The features should contain less sensitive elements and they are implicitly related to the target illness. Therefore exchanging questions and answers about a few carefully chosen features in an open channel would not easily or directly expose the illness, but yet it can verify by inference whether the user has a record of it stored in his smart card. The design of a privacy preserving model by backward inference is introduced in this paper. Some live medical data are used in experiments for validation and demonstration.
Oleari, Claudio; Melgosa, Manuel; Huertas, Rafael
2011-11-01
The most widely used color-difference formulas are based on color-difference data obtained under D65 illumination or similar and for a 10° visual field; i.e., these formulas hold true for the CIE 1964 observer adapted to D65 illuminant. This work considers the psychometric color-vision model based on the Optical Society of America-Uniform Color Scales (OSA-UCS) system previously published by the first author [J. Opt. Soc. Am. A 21, 677 (2004); Color Res. Appl. 30, 31 (2005)] with the additional hypothesis that complete illuminant adaptation with perfect color constancy exists in the visual evaluation of color differences. In this way a computational procedure is defined for color conversion between different illuminant adaptations, which is an alternative to the current chromatic adaptation transforms. This color conversion allows the passage between different observers, e.g., CIE 1964 and CIE 1931. An application of this color conversion is here made in the color-difference evaluation for any observer and in any illuminant adaptation: these transformations convert tristimulus values related to any observer and illuminant adaptation to those related to the observer and illuminant adaptation of the definition of the color-difference formulas, i.e., to the CIE 1964 observer adapted to the D65 illuminant, and then the known color-difference formulas can be applied. The adaptations to the illuminants A, C, F11, D50, Planckian and daylight at any color temperature and for CIE 1931 and CIE 1964 observers are considered as examples, and all the corresponding transformations are given for practical use.
Overlapped optics induced perfect coherent effects
Li, Jian Jie; Zang, Xiao Fei; Mao, Jun Fa; Tang, Min; Zhu, Yi Ming; Zhuang, Song Lin
2013-12-01
For traditional coherent effects, two separated identical point sources can be interfered with each other only when the optical path difference is integer number of wavelengths, leading to alternate dark and bright fringes for different optical path difference. For hundreds of years, such a perfect coherent condition seems insurmountable. However, in this paper, based on transformation optics, two separated in-phase identical point sources can induce perfect interference with each other without satisfying the traditional coherent condition. This shifting illusion media is realized by inductor-capacitor transmission line network. Theoretical analysis, numerical simulations and experimental results are performed to confirm such a kind of perfect coherent effect and it is found that the total radiation power of multiple elements system can be greatly enhanced. Our investigation may be applicable to National Ignition Facility (NIF), Inertial Confined Fusion (ICF) of China, LED lighting technology, terahertz communication, and so on.
Overlapped optics induced perfect coherent effects.
Li, Jian Jie; Zang, Xiao Fei; Mao, Jun Fa; Tang, Min; Zhu, Yi Ming; Zhuang, Song Lin
2013-12-20
For traditional coherent effects, two separated identical point sources can be interfered with each other only when the optical path difference is integer number of wavelengths, leading to alternate dark and bright fringes for different optical path difference. For hundreds of years, such a perfect coherent condition seems insurmountable. However, in this paper, based on transformation optics, two separated in-phase identical point sources can induce perfect interference with each other without satisfying the traditional coherent condition. This shifting illusion media is realized by inductor-capacitor transmission line network. Theoretical analysis, numerical simulations and experimental results are performed to confirm such a kind of perfect coherent effect and it is found that the total radiation power of multiple elements system can be greatly enhanced. Our investigation may be applicable to National Ignition Facility (NIF), Inertial Confined Fusion (ICF) of China, LED lighting technology, terahertz communication, and so on.
Mocellin, Simone; Shrager, Jeff; Scolyer, Richard; Pasquali, Sandro; Verdi, Daunia; Marincola, Francesco M; Briarava, Marta; Gobbel, Randy; Rossi, Carlo; Nitti, Donato
2010-08-10
The efficacy of current anticancer treatments is far from satisfactory and many patients still die of their disease. A general agreement exists on the urgency of developing molecularly targeted therapies, although their implementation in the clinical setting is in its infancy. In fact, despite the wealth of preclinical studies addressing these issues, the difficulty of testing each targeted therapy hypothesis in the clinical arena represents an intrinsic obstacle. As a consequence, we are witnessing a paradoxical situation where most hypotheses about the molecular and cellular biology of cancer remain clinically untested and therefore do not translate into a therapeutic benefit for patients. To present a computational method aimed to comprehensively exploit the scientific knowledge in order to foster the development of personalized cancer treatment by matching the patient's molecular profile with the available evidence on targeted therapy. To this aim we focused on melanoma, an increasingly diagnosed malignancy for which the need for novel therapeutic approaches is paradigmatic since no effective treatment is available in the advanced setting. Relevant data were manually extracted from peer-reviewed full-text original articles describing any type of anti-melanoma targeted therapy tested in any type of experimental or clinical model. To this purpose, Medline, Embase, Cancerlit and the Cochrane databases were searched. We created a manually annotated database (Targeted Therapy Database, TTD) where the relevant data are gathered in a formal representation that can be computationally analyzed. Dedicated algorithms were set up for the identification of the prevalent therapeutic hypotheses based on the available evidence and for ranking treatments based on the molecular profile of individual patients. In this essay we describe the principles and computational algorithms of an original method developed to fully exploit the available knowledge on cancer biology with the
Chaisaowong, Kraisorn; Kraus, Thomas
2014-03-01
Pleural thickenings can be caused by asbestos exposure and may evolve into malignant pleural mesothelioma. While an early diagnosis plays the key role to an early treatment, and therefore helping to reduce morbidity, the growth rate of a pleural thickening can be in turn essential evidence to an early diagnosis of the pleural mesothelioma. The detection of pleural thickenings is today done by a visual inspection of CT data, which is time-consuming and underlies the physician's subjective judgment. Computer-assisted diagnosis systems to automatically assess pleural mesothelioma have been reported worldwide. But in this paper, an image analysis pipeline to automatically detect pleural thickenings and measure their volume is described. We first delineate automatically the pleural contour in the CT images. An adaptive surface-base smoothing technique is then applied to the pleural contours to identify all potential thickenings. A following tissue-specific topology-oriented detection based on a probabilistic Hounsfield Unit model of pleural plaques specify then the genuine pleural thickenings among them. The assessment of the detected pleural thickenings is based on the volumetry of the 3D model, created by mesh construction algorithm followed by Laplace-Beltrami eigenfunction expansion surface smoothing technique. Finally, the spatiotemporal matching of pleural thickenings from consecutive CT data is carried out based on the semi-automatic lung registration towards the assessment of its growth rate. With these methods, a new computer-assisted diagnosis system is presented in order to assure a precise and reproducible assessment of pleural thickenings towards the diagnosis of the pleural mesothelioma in its early stage.
Hamiltonian formalism for perfect fluids in general relativity
International Nuclear Information System (INIS)
Demaret, J.; Moncrief, V.
1980-01-01
Schutz's Hamiltonian theory of a relativistic perfect fluid, based on the velocity-potential version of classical perfect fluid hydrodynamics as formulated by Seliger and Whitham, is used to derive, in the framework of the Arnowitt, Deser, and Misner (ADM) method, a general partially reduced Hamiltonian for relativistic systems filled with a perfect fluid. The time coordinate is chosen, as in Lund's treatment of collapsing balls of dust, as minus the only velocity potential different from zero in the case of an irrotational and isentropic fluid. A ''semi-Dirac'' method can be applied to quantize astrophysical and cosmological models in the framework of this partially reduced formalism. If one chooses Taub's adapted comoving coordinate system, it is possible to derive a fully reduced ADM Hamiltonian, which is equal to minus the total baryon number of the fluid, generalizing a result previously obtained by Moncrief in the more particular framework of Taub's variational principle, valid for self-gravitating barotropic relativistic perfect fluids. An unconstrained Hamiltonian density is then explicitly derived for a fluid obeying the equation of state p=(gamma-1)rho (1 < or = γ < or = 2), which can adequately describe the phases of very high density attained in a catastrophic collapse or during the early stages of the Universe. This Hamiltonian density, shown to be equivalent to Moncrief's in the particular case of an isentropic fluid, can be simplified for fluid-filled class-A diagonal Bianchi-type cosmological models and appears as a suitable starting point for the study of the canonical quantization of these models
A Hypergraph Dictatorship Test with Perfect Completeness
Chen, Victor
A hypergraph dictatorship test is first introduced by Samorodnitsky and Trevisan and serves as a key component in their unique games based {operatorname{PCP}} construction. Such a test has oracle access to a collection of functions and determines whether all the functions are the same dictatorship, or all their low degree influences are o(1). Their test makes q ≥ 3 queries, has amortized query complexity 1+Oleft(log q/qright), but has an inherent loss of perfect completeness. In this paper we give an (adaptive) hypergraph dictatorship test that achieves both perfect completeness and amortized query complexity 1+Oleft(log q/qright).
Optimal simulation of a perfect entangler
International Nuclear Information System (INIS)
Yu Nengkun; Duan Runyao; Ying Mingsheng
2010-01-01
A 2 x 2 unitary operation is called a perfect entangler if it can generate a maximally entangled state from some unentangled input. We study the following question: How many runs of a given two-qubit entangling unitary operation are required to simulate some perfect entangler with one-qubit unitary operations as free resources? We completely solve this problem by presenting an analytical formula for the optimal number of runs of the entangling operation. Our result reveals an entanglement strength of two-qubit unitary operations.
Perfect 800 Advanced Strategies for Top Students
Celenti, Dan
2010-01-01
Getting into the nation's most competitive universities requires more than a good SAT score, it requires a perfect score. Perfect 800: SAT Math gives advanced students the tools needed to master the SAT math test. Covering areas including arithmetic concepts; algebra; geometry; and additional topics such as probability and weighted average, the book offers exposure to a wide range of degrees of difficulty in a holistic approach that allows students to experience the "real thing," including the impact of time constraints on their performance. By emphasizing critical thinking and analytic skills
Lattice-Like Total Perfect Codes
Directory of Open Access Journals (Sweden)
Araujo Carlos
2014-02-01
Full Text Available A contribution is made to the classification of lattice-like total perfect codes in integer lattices Λn via pairs (G, Φ formed by abelian groups G and homomorphisms Φ: Zn → G. A conjecture is posed that the cited contribution covers all possible cases. A related conjecture on the unfinished work on open problems on lattice-like perfect dominating sets in Λn with induced components that are parallel paths of length > 1 is posed as well.
Optimization of Perfect Absorbers with Multilayer Structures
Li Voti, Roberto
2018-02-01
We study wide-angle and broadband perfect absorbers with compact multilayer structures made of a sequence of ITO and TiN layers deposited onto a silver thick layer. An optimization procedure is introduced for searching the optimal thicknesses of the layers so as to design a perfect broadband absorber from 400 nm to 750 nm, for a wide range of angles of incidence from 0{°} to 50{°}, for both polarizations and with a low emissivity in the mid-infrared. We eventually compare the performances of several optimal structures that can be very promising for solar thermal energy harvesting and collectors.
Hypersurface-homogeneous Universe filled with perfect fluid in f ( R ...
Indian Academy of Sciences (India)
homogeneous Universe filled with perfect fluid in the framework of f ( R , T ) theory of gravity (Harko et al, \\emph{Phys. Rev.} D 84, 024020 (2011)) is derived. The physical behaviour of the cosmological model is studied.
Hypersurface-homogeneous Universe filled with perfect fluid in f (R ...
Indian Academy of Sciences (India)
homogeneous Universe filled with perfect fluid in the framework of f ( R , T ) theory of gravity (Harko et al, \\emph{Phys. Rev.} D 84, 024020 (2011)) is derived. The physical behaviour of the cosmological model is studied.
Matching Games with Additive Externalities
DEFF Research Database (Denmark)
Branzei, Simina; Michalak, Tomasz; Rahwan, Talal
2012-01-01
Two-sided matchings are an important theoretical tool used to model markets and social interactions. In many real life problems the utility of an agent is influenced not only by their own choices, but also by the choices that other agents make. Such an influence is called an externality. Whereas...... fully expressive representations of externalities in matchings require exponential space, in this paper we propose a compact model of externalities, in which the influence of a match on each agent is computed additively. In this framework, we analyze many-to-many and one-to-one matchings under neutral...
Coordinate transformations make perfect invisibility cloaks with arbitrary shape
International Nuclear Information System (INIS)
Yan Wei; Yan Min; Ruan Zhichao; Qiu Min
2008-01-01
By investigating wave properties at cloak boundaries, invisibility cloaks with arbitrary shape constructed by general coordinate transformations are confirmed to be perfectly invisible to the external incident wave. The differences between line transformed cloaks and point transformed cloaks are discussed. The fields in the cloak medium are found analytically to be related to the fields in the original space via coordinate transformation functions. At the exterior boundary of the cloak, it is shown that no reflection is excited even though the permittivity and permeability do not always have a perfectly matched layer form, whereas at the inner boundary, no reflection is excited either, and in particular no field can penetrate into the cloaked region. However, for the inner boundary of any line transformed cloak, the permittivity and permeability in a specific tangential direction are always required to be infinitely large. Furthermore, the field discontinuity at the inner boundary always exists; the surface current is induced to make this discontinuity self-consistent. A point transformed cloak does not experience such problems. The tangential fields at the inner boundary are all zero, implying that no field discontinuity exists
Coordinate transformations make perfect invisibility cloaks with arbitrary shape
Energy Technology Data Exchange (ETDEWEB)
Yan Wei; Yan Min; Ruan Zhichao; Qiu Min [Laboratory of Optics, Photonics and Quantum Electronics, Department of Microelectronics and Applied Physics, Royal Institute of Technology, 164 40 Kista (Sweden)], E-mail: min@kth.se
2008-04-15
By investigating wave properties at cloak boundaries, invisibility cloaks with arbitrary shape constructed by general coordinate transformations are confirmed to be perfectly invisible to the external incident wave. The differences between line transformed cloaks and point transformed cloaks are discussed. The fields in the cloak medium are found analytically to be related to the fields in the original space via coordinate transformation functions. At the exterior boundary of the cloak, it is shown that no reflection is excited even though the permittivity and permeability do not always have a perfectly matched layer form, whereas at the inner boundary, no reflection is excited either, and in particular no field can penetrate into the cloaked region. However, for the inner boundary of any line transformed cloak, the permittivity and permeability in a specific tangential direction are always required to be infinitely large. Furthermore, the field discontinuity at the inner boundary always exists; the surface current is induced to make this discontinuity self-consistent. A point transformed cloak does not experience such problems. The tangential fields at the inner boundary are all zero, implying that no field discontinuity exists.
Non-adiabatic perturbations in multi-component perfect fluids
Energy Technology Data Exchange (ETDEWEB)
Koshelev, N.A., E-mail: koshna71@inbox.ru [Ulyanovsk State University, Leo Tolstoy str 42, 432970 (Russian Federation)
2011-04-01
The evolution of non-adiabatic perturbations in models with multiple coupled perfect fluids with non-adiabatic sound speed is considered. Instead of splitting the entropy perturbation into relative and intrinsic parts, we introduce a set of symmetric quantities, which also govern the non-adiabatic pressure perturbation in models with energy transfer. We write the gauge invariant equations for the variables that determine on a large scale the non-adiabatic pressure perturbation and the rate of changes of the comoving curvature perturbation. The analysis of evolution of the non-adiabatic pressure perturbation has been made for several particular models.
Non-adiabatic perturbations in multi-component perfect fluids
International Nuclear Information System (INIS)
Koshelev, N.A.
2011-01-01
The evolution of non-adiabatic perturbations in models with multiple coupled perfect fluids with non-adiabatic sound speed is considered. Instead of splitting the entropy perturbation into relative and intrinsic parts, we introduce a set of symmetric quantities, which also govern the non-adiabatic pressure perturbation in models with energy transfer. We write the gauge invariant equations for the variables that determine on a large scale the non-adiabatic pressure perturbation and the rate of changes of the comoving curvature perturbation. The analysis of evolution of the non-adiabatic pressure perturbation has been made for several particular models
Directory of Open Access Journals (Sweden)
Rahul Subramanian
2016-12-01
Full Text Available Despite the availability of vaccines, influenza remains a major public health challenge. A key reason is the virus capacity for immune escape: ongoing evolution allows the continual circulation of seasonal influenza, while novel influenza viruses invade the human population to cause a pandemic every few decades. Current vaccines have to be updated continually to keep up to date with this antigenic change, but emerging 'universal' vaccines-targeting more conserved components of the influenza virus-offer the potential to act across all influenza A strains and subtypes. Influenza vaccination programmes around the world are steadily increasing in their population coverage. In future, how might intensive, routine immunization with novel vaccines compare against similar mass programmes utilizing conventional vaccines? Specifically, how might novel and conventional vaccines compare, in terms of cumulative incidence and rates of antigenic evolution of seasonal influenza? What are their potential implications for the impact of pandemic emergence? Here we present a new mathematical model, capturing both transmission dynamics and antigenic evolution of influenza in a simple framework, to explore these questions. We find that, even when matched by per-dose efficacy, universal vaccines could dampen population-level transmission over several seasons to a greater extent than conventional vaccines. Moreover, by lowering opportunities for cross-protective immunity in the population, conventional vaccines could allow the increased spread of a novel pandemic strain. Conversely, universal vaccines could mitigate both seasonal and pandemic spread. However, where it is not possible to maintain annual, intensive vaccination coverage, the duration and breadth of immunity raised by universal vaccines are critical determinants of their performance relative to conventional vaccines. In future, conventional and novel vaccines are likely to play complementary roles in
Koga, Hideyuki; Nakamae, Atsuo; Shima, Yosuke; Bahr, Roald; Krosshaug, Tron
2018-02-01
Detailed kinematic descriptions of real anterior cruciate ligament (ACL) injury situations are limited to the knee only. To describe hip and ankle kinematics as well as foot position relative to the center of mass (COM) in ACL injury situations through use of a model-based image-matching (MBIM) technique. The distance between the projection of the COM on the ground and the base of support (BOS) (COM_BOS) normalized to the femur length was also evaluated. Descriptive laboratory study. Ten ACL injury video sequences from women's handball and basketball were analyzed. Hip and ankle joint kinematic values were obtained by use of MBIM. The mean hip flexion angle was 51° (95% CI, 41° to 63°) at initial contact and remained constant over the next 40 milliseconds. The hip was internally rotated 29° (95% CI, 18° to 39°) at initial contact and remained unchanged for the next 40 milliseconds. All of the injured patients landed with a heel strike with a mean dorsiflexion angle of 2° (95% CI, -9° to 14°), before reaching a flatfooted position 20 milliseconds later. The foot position was anterior and lateral to the COM in all cases. However, none of the results showed larger COM_BOS than 1.2, which has been suggested as a criterion for ACL injury risk. Hip kinematic values were consistent among the 10 ACL injury situations analyzed; the hip joint remained unchanged in a flexed and internally rotated position in the phase leading up to injury, suggesting that limited energy absorption took place at the hip. In all cases, the foot contacted the ground with the heel strike. However, relatively small COM_BOS distances were found, indicating that the anterior and lateral foot placement in ACL injury situations was not different from what can be expected in noninjury game situations.
The dispersion and matching characteristics of the helical resonator plasma source
Energy Technology Data Exchange (ETDEWEB)
Niazi, K.; Lichtenberg, A.J.; Lieberman, M.A. [Univ. of California, Berkeley, CA (United States)
1995-10-01
The dispersion characteristics and the fields of a helical resonator are obtained. The coil is approximated by a helical current layer with infinite conductivity along the current direction (a ``sheath helix``). The plasma column is modeled as a cylindrical dielectric in which the dielectric losses can be neglected in determining the propagation properties of the resonator. Assuming the plasma losses are known, the model can be used to study the matching of the helical resonator to an external power source which is connected to the helix by a tap. The resonator is modeled as a parallel connection of two transmission line segments on each side of the tap position. The authors determine the efficiency of power transfer to the resonator as a function of the tap position driving frequency, and plasma loading. They find that whereas for a small plasma loading it is possible to achieve perfect matching, there exists a critical value of plasma loading beyond which a perfect match is no longer possible.
Mechanical Energy Changes in Perfectly Inelastic Collisions
Mungan, Carl E.
2013-01-01
Suppose a block of mass "m"[subscript 1] traveling at speed "v"[subscript 1] makes a one-dimensional perfectly inelastic collision with another block of mass "m"[subscript 2]. What else does one need to know to calculate the fraction of the mechanical energy that is dissipated in the collision? (Contains 1 figure.)
Perfectly Secure Oblivious RAM without Random Oracles
DEFF Research Database (Denmark)
Damgård, Ivan Bjerre; Meldgaard, Sigurd Torkel; Nielsen, Jesper Buus
2011-01-01
We present an algorithm for implementing a secure oblivious RAM where the access pattern is perfectly hidden in the information theoretic sense, without assuming that the CPU has access to a random oracle. In addition we prove a lower bound on the amount of randomness needed for implementing...... an information theoretically secure oblivious RAM....
Perfect and Periphrastic Passive Constructions in Danish
DEFF Research Database (Denmark)
Bjerre, Tavs; Bjerre, Anne
2007-01-01
This paper gives an account of the event and argument structure of past participles and the linking between argument structure and valence structure. It further accounts for how participles form perfect and passiv constructions with auxiliaries. We assume that the same participle form is used in ...
Le Perfectionnement en Phonetique (Perfecting Phonetics)
Laroche-Bouvy, Danielle
1975-01-01
This article describes the programs of the Institut d'Etudes Linguistiques et Phonetiques, located in Paris. The program focuses on perfecting the students' phonetic production of French. Both curriculum and teaching methods are described, as well as a course in phonetics for future teachers of French. (Text is in French.) (CLK)
Reshaping the perfect electrical conductor cylinder arbitrarily
International Nuclear Information System (INIS)
Chen Huanyang; Zhang Xiaohe; Luo Xudong; Ma Hongru; Chan Cheting
2008-01-01
A general method is proposed to design a cylindrical cloak, concentrator and superscatterer with an arbitrary cross section. The method is demonstrated by the design of a perfect electrical conductor (PEC) reshaper which is able to reshape a PEC cylinder arbitrarily by combining the concept of cloak, concentrator and superscatterer together. Numerical simulations are performed to demonstrate its properties.
Diamagnetic expansions for perfect quantum gases
DEFF Research Database (Denmark)
Briet, Philippe; Cornean, Horia; Louis, Delphine
2006-01-01
In this work we study the diamagnetic properties of a perfect quantum gas in the presence of a constant magnetic field of intensity B. We investigate the Gibbs semigroup associated with the one particle operator at finite volume, and study its Taylor series with respect to the field parameter ome...
Directory of Open Access Journals (Sweden)
Simone Mocellin
Full Text Available BACKGROUND: The efficacy of current anticancer treatments is far from satisfactory and many patients still die of their disease. A general agreement exists on the urgency of developing molecularly targeted therapies, although their implementation in the clinical setting is in its infancy. In fact, despite the wealth of preclinical studies addressing these issues, the difficulty of testing each targeted therapy hypothesis in the clinical arena represents an intrinsic obstacle. As a consequence, we are witnessing a paradoxical situation where most hypotheses about the molecular and cellular biology of cancer remain clinically untested and therefore do not translate into a therapeutic benefit for patients. OBJECTIVE: To present a computational method aimed to comprehensively exploit the scientific knowledge in order to foster the development of personalized cancer treatment by matching the patient's molecular profile with the available evidence on targeted therapy. METHODS: To this aim we focused on melanoma, an increasingly diagnosed malignancy for which the need for novel therapeutic approaches is paradigmatic since no effective treatment is available in the advanced setting. Relevant data were manually extracted from peer-reviewed full-text original articles describing any type of anti-melanoma targeted therapy tested in any type of experimental or clinical model. To this purpose, Medline, Embase, Cancerlit and the Cochrane databases were searched. RESULTS AND CONCLUSIONS: We created a manually annotated database (Targeted Therapy Database, TTD where the relevant data are gathered in a formal representation that can be computationally analyzed. Dedicated algorithms were set up for the identification of the prevalent therapeutic hypotheses based on the available evidence and for ranking treatments based on the molecular profile of individual patients. In this essay we describe the principles and computational algorithms of an original method
Burnham, Christian J.; Futera, Zdenek; English, Niall J.
2018-03-01
The force-matching method has been applied to parameterise an empirical potential model for water-water and water-hydrogen intermolecular interactions for use in clathrate-hydrate simulations containing hydrogen guest molecules. The underlying reference simulations constituted ab initio molecular dynamics (AIMD) of clathrate hydrates with various occupations of hydrogen-molecule guests. It is shown that the resultant model is able to reproduce AIMD-derived free-energy curves for the movement of a tagged hydrogen molecule between the water cages that make up the clathrate, thus giving us confidence in the model. Furthermore, with the aid of an umbrella-sampling algorithm, we calculate barrier heights for the force-matched model, yielding the free-energy barrier for a tagged molecule to move between cages. The barrier heights are reasonably large, being on the order of 30 kJ/mol, and are consistent with our previous studies with empirical models [C. J. Burnham and N. J. English, J. Phys. Chem. C 120, 16561 (2016) and C. J. Burnham et al., Phys. Chem. Chem. Phys. 19, 717 (2017)]. Our results are in opposition to the literature, which claims that this system may have very low barrier heights. We also compare results to that using the more ad hoc empirical model of Alavi et al. [J. Chem. Phys. 123, 024507 (2005)] and find that this model does very well when judged against the force-matched and ab initio simulation data.
Lachin, John M
2008-06-30
The conditional logistic regression model (Biometrics 1982; 38:661-672) provides a convenient method for the assessment of qualitative or quantitative covariate effects on risk in a study with matched sets, each containing a possibly different number of cases and controls. The conditional logistic likelihood is identical to the stratified Cox proportional hazards model likelihood, with an adjustment for ties (J. R. Stat. Soc. B 1972; 34:187-220). This likelihood also applies to a nested case-control study with multiply matched cases and controls, selected from those at risk at selected event times. Herein the distribution of the score test for the effect of a covariate in the model is used to derive simple equations to describe the power of the test to detect a coefficient theta (log odds ratio or log hazard ratio) or the number of cases (or matched sets) and controls required to provide a desired level of power. Additional expressions are derived for a quantitative covariate as a function of the difference in the assumed mean covariate values among cases and controls and for a qualitative covariate in terms of the difference in the probabilities of exposure for cases and controls. Examples are presented for a nested case-control study and a multiply matched case-control study.
Kumar, Raj G; Wang, Zhensheng; Kesinger, Matthew R; Newman, Mark; Huynh, Toan T; Niemeier, Janet P; Sperry, Jason L; Wagner, Amy K
2018-04-01
In a previous study, individuals from a single Traumatic Brain Injury Model Systems and trauma center were matched using a novel probabilistic matching algorithm. The Traumatic Brain Injury Model Systems is a multicenter prospective cohort study containing more than 14,000 participants with traumatic brain injury, following them from inpatient rehabilitation to the community over the remainder of their lifetime. The National Trauma Databank is the largest aggregation of trauma data in the United States, including more than 6 million records. Linking these two databases offers a broad range of opportunities to explore research questions not otherwise possible. Our objective was to refine and validate the previous protocol at another independent center. An algorithm generation and validation data set were created, and potential matches were blocked by age, sex, and year of injury; total probabilistic weight was calculated based on of 12 common data fields. Validity metrics were calculated using a minimum probabilistic weight of 3. The positive predictive value was 98.2% and 97.4% and sensitivity was 74.1% and 76.3%, in the algorithm generation and validation set, respectively. These metrics were similar to the previous study. Future work will apply the refined probabilistic matching algorithm to the Traumatic Brain Injury Model Systems and the National Trauma Databank to generate a merged data set for clinical traumatic brain injury research use.
Approximating perfection a mathematician's journey into the world of mechanics
Lebedev, Leonid P
2004-01-01
This is a book for those who enjoy thinking about how and why Nature can be described using mathematical tools. Approximating Perfection considers the background behind mechanics as well as the mathematical ideas that play key roles in mechanical applications. Concentrating on the models of applied mechanics, the book engages the reader in the types of nuts-and-bolts considerations that are normally avoided in formal engineering courses: how and why models remain imperfect, and the factors that motivated their development. The opening chapter reviews and reconsiders the basics of c
Directory of Open Access Journals (Sweden)
Nima Tabatabaei
2018-04-01
Full Text Available Conventional infrared thermography techniques, including pulsed and lock-in thermography, have shown great potential for non-destructive evaluation of broad spectrum of materials, spanning from metals to polymers to biological tissues. However, performance of these techniques is often limited due to the diffuse nature of thermal wave fields, resulting in an inherent compromise between inspection depth and depth resolution. Recently, matched-filter thermography has been introduced as a means for overcoming this classic limitation to enable depth-resolved subsurface thermal imaging and improving axial/depth resolution. This paper reviews the basic principles and experimental results of matched-filter thermography: first, mathematical and signal processing concepts related to matched-fileting and pulse compression are discussed. Next, theoretical modeling of thermal-wave responses to matched-filter thermography using two categories of pulse compression techniques (linear frequency modulation and binary phase coding are reviewed. Key experimental results from literature demonstrating the maintenance of axial resolution while inspecting deep into opaque and turbid media are also presented and discussed. Finally, the concept of thermal coherence tomography for deconvolution of thermal responses of axially superposed sources and creation of depth-selective images in a diffusion-wave field is reviewed.
Thermodynamical stability for a perfect fluid
Energy Technology Data Exchange (ETDEWEB)
Fang, Xiongjun; Jing, Jiliang [Hunan Normal University, Department of Physics, Key Laboratory of Low Dimensional Quantum Structures and Quantum Control of Ministry of Education, and Synergetic Innovation Center for Quantum Effects and Applications, Changsha, Hunan (China); He, Xiaokai [Hunan Normal University, Department of Physics, Key Laboratory of Low Dimensional Quantum Structures and Quantum Control of Ministry of Education, and Synergetic Innovation Center for Quantum Effects and Applications, Changsha, Hunan (China); Hunan First Normal University, School of Mathematics and Computational Science, Changsha (China)
2017-12-15
According to the maximum entropy principle, it has been proved that the gravitational field equations could be derived by the extrema of the total entropy for a perfect fluid, which implies that thermodynamic relations contain information as regards gravity. In this manuscript, we obtain a criterion for the thermodynamical stability of an adiabatic, self-gravitating perfect fluid system by the second variation of the total entropy. We show, for Einstein's gravity with spherical symmetry spacetime, that the criterion is consistent with that for the dynamical stability derived by Chandrasekhar and Wald. We also find that the criterion could be applied to cases without spherical symmetry, or under general perturbations. The result further establishes the connection between thermodynamics and gravity. (orig.)
Thermodynamical stability for a perfect fluid
Fang, Xiongjun; He, Xiaokai; Jing, Jiliang
2017-12-01
According to the maximum entropy principle, it has been proved that the gravitational field equations could be derived by the extrema of the total entropy for a perfect fluid, which implies that thermodynamic relations contain information as regards gravity. In this manuscript, we obtain a criterion for the thermodynamical stability of an adiabatic, self-gravitating perfect fluid system by the second variation of the total entropy. We show, for Einstein's gravity with spherical symmetry spacetime, that the criterion is consistent with that for the dynamical stability derived by Chandrasekhar and Wald. We also find that the criterion could be applied to cases without spherical symmetry, or under general perturbations. The result further establishes the connection between thermodynamics and gravity.
Nonminimal coupling of perfect fluids to curvature
International Nuclear Information System (INIS)
Bertolami, Orfeu; Lobo, Francisco S. N.; Paramos, Jorge
2008-01-01
In this work, we consider different forms of relativistic perfect fluid Lagrangian densities that yield the same gravitational field equations in general relativity (GR). A particularly intriguing example is the case with couplings of the form [1+f 2 (R)]L m , where R is the scalar curvature, which induces an extra force that depends on the form of the Lagrangian density. It has been found that, considering the Lagrangian density L m =p, where p is the pressure, the extra-force vanishes. We argue that this is not the unique choice for the matter Lagrangian density, and that more natural forms for L m do not imply the vanishing of the extra force. Particular attention is paid to the impact on the classical equivalence between different Lagrangian descriptions of a perfect fluid.
Population growth rates in perfect contraceptive populations.
Udry, J R; Bauman, K E; Chase, C L
1973-07-01
Abstract Eventually, world population must cease to grow. In many countries attempts are made to decrease population growth by providing family planning services to all who want to prevent pregnancies. In this paper we use the concept 'perfect contraceptive population',(1) - a population in which no unwanted births occur - to derive estimates of the maximum contribution that prevention of unwanted births might make toward attaining a zero rate of natural increase in population.
Another Class of Perfect Nonlinear Polynomial Functions
Directory of Open Access Journals (Sweden)
Menglong Su
2013-01-01
Full Text Available Perfect nonlinear (PN functions have been an interesting subject of study for a long time and have applications in coding theory, cryptography, combinatorial designs, and so on. In this paper, the planarity of the trinomials xpk+1+ux2+vx2pk over GF(p2k are presented. This class of PN functions are all EA-equivalent to x2.
The perfect crime: myth or reality?
Fanton, L; Miras, A; Tilhet-Coartet, S; Achache, P; Malicier, D
1998-09-01
The primum movens of a forensic autopsy is to track down the crime. The perfect crime can be defined as one which will never be suspected and/or one for which the criminal will never be arrested. We have reported several cases that have been adjudicated or are being adjudicated, and we show how actual homicides could have been taken for accidental deaths, suicides, or even natural deaths.
Directory of Open Access Journals (Sweden)
Daitin Tarigan
2014-06-01
Full Text Available AbstrakPenelitian ini bertujuan untuk mengetahui aktivitas belajar siswa pada mata pelajaran Matematika materi mengubah pecahan ke bentuk persen, desimal dan sebaliknya dengan menggunakan model make a match di kelas V SD Negeri 050687 Sawit Seberang T.A 2013/2014. Jenis penelitian ini adalah Penelitian Tindakan Kelas (PTK dengan alat pengumpulan data yang digunakan adalah lembar observasi aktivitas guru dan siswa. Berdasarkan analisis data diperoleh hasil pada siklus I Pertemuan I skor aktivitas guru adalah 82,14 dengan kriteria baik dan aktivitas belajar dalah aktif. Tindakan dilanjutkan sampai dengan siklus ke II. Pada pertemuan II siklus II skor aktivitas guru adalah 96,42 dengan kriteria sangat baik dan aktivitas belajar klasikal adalah sangat aktif. Dari hasil tersebut dapat diambil kesimpulan bahwa tindakan penelitian berhasil karena nilai indikator aktivitas belajar siswa dan jumlah siswa yang dinyatakan aktif secara klasikal telah mencapai 80%. Dengan demikian maka penggunaan model make a match dapat meningkatkan aktivitas belajar siswa di kelas V SD Negeri 050687 Sawit Seberang pada mata pelajaran Matematika materi mengubah pecahan ke bentuk persen, desimal. Kata Kunci: Model Make a Match; Aktivitas Belajar Siswa AbstractThis reseach aim is to know the student activity on Math at topic change the fraction into percent, desimal and vice versa, using make a match model on fifth grade of SDN 050687 Sawit Seberang 2013/2014. This is a classroom action research which is used activity observrvation sheet as its instrumen of collecting data. From the analisys of data, it is got result as follows: on cycle I meet I, teacher activity score is 82,14, which was mean good, and learning activity was active. The action and then continued until second cycle. On the meet II cylce II, it was got teacher activity score is 96,42, which was mean very good, and clasical learning activity was very active. Based on the result, it was conclude
DEFF Research Database (Denmark)
Faust, Sebastian; Hazay, Carmit; Venturi, Daniele
2013-01-01
In secure delegatable computation, computationally weak devices (or clients) wish to outsource their computation and data to an untrusted server in the cloud. While most earlier work considers the general question of how to securely outsource any computation to the cloud server, we focus...... and the client C T in order to learn the positions at which a pattern of length m matches the text (and nothing beyond that). This is called the outsourced pattern matching problem and is highly motivated in the context of delegatable computing since it offers storage alternatives for massive databases...... that contain confidential data (e.g., health related data about patient history). Our constructions offer simulation-based security in the presence of semi-honest and malicious adversaries (in the random oracle model) and limit the communication in the query phase to O(m) bits plus the number of occurrences...
Matchings Extend to Hamiltonian Cycles in 5-Cube
Directory of Open Access Journals (Sweden)
Wang Fan
2018-02-01
Full Text Available Ruskey and Savage asked the following question: Does every matching in a hypercube Qn for n ≥ 2 extend to a Hamiltonian cycle of Qn? Fink confirmed that every perfect matching can be extended to a Hamiltonian cycle of Qn, thus solved Kreweras’ conjecture. Also, Fink pointed out that every matching can be extended to a Hamiltonian cycle of Qn for n ∈ {2, 3, 4}. In this paper, we prove that every matching in Q5 can be extended to a Hamiltonian cycle of Q5.
NMR-based metabolomics and hyphenated NMR techniques – a perfect match in natural products research
DEFF Research Database (Denmark)
Vinther, Joachim Møllesøe; Wubshet, Sileshi Gizachew; Stærk, Dan
2015-01-01
Ethnopharmacology is one of the world’s fastest-growing scientific disciplines encompassing a diverse range of subjects. It links natural sciences research on medicinal, aromatic and toxic plants with socio-cultural studies and has often been associated with the development of new drugs...
National Aeronautics and Space Administration — Thermophotovoltaic(TPV) energy conversion produces electrical power from heat energy in a simple, low maintenance manner ideal for certain NASA applications....
Reviews : Work by Tüür radiates beauty. Järvi & Tubin : perfect match
2005-01-01
E.-S. Tüüri teosed "Action-Passion-Illusion, Zeitraum" heliplaadil (dir. Anu Tali). Detroidi Sümfooniaorkester esitas Neeme Järvi juhatamisel Ed. Tubina "Sümfoonia N. 5" Detroidi Kontserdimajas 21. aprillil
Perfect Match? The Practice Ecology of a Labor Market Initiative for Refugees
DEFF Research Database (Denmark)
Buch, Anders; Berthou, Sara Kristine Gløjmar
2018-01-01
the practices exist and are interconnected in ecological arrangements where practice architectures hold one another in place. The theoretical conceptualization in terms of practice, practices, practice architectures, and practice ecologies helps to explain how a seemingly ideal initiative turned out to have...
Solomon, Norman A.; Scherer, Robert F.; Oliveti, Joseph J.; Mochel, Lucienne; Bryant, Michael
2017-01-01
Initial Association to Advance Collegiate Schools of Business International accreditation involves a process of pairing mentor and host schools to provide guidance and feedback on the congruence of the host school with the accreditation standards. The mentor serves as the primary resource for assisting the host school in identifying gaps with the…
Bortezomib and TRAIL : A perfect match for apoptotic elimination of tumour cells?
de Wilt, L. H. A. M.; Kroon, J.; Jansen, G.; de Jong, S.; Peters, G. J.; Kruyt, F. A. E.
Tumour necrosis factor-related apoptosis-inducing ligand (TRAIL) is a cytokine that selectively eradicates tumour cells via specific cell surface receptors and is intensively explored for use as a novel anticancer approach. To enhance the efficacy of TRAIL receptor agonists the proteasome inhibitor
The oil crisis: China, the perfect scapegoat
International Nuclear Information System (INIS)
Lafargue, F.
2008-01-01
The Western economies have been confronted with rising oil prices for the past five years. Political instability in the Middle East, social unrest in Nigeria and Hugo Chavez nationalizations all reinforce our dread of a shortage. This oil crisis is often presented as the consequence of the rapid industrialization of India and China. As so often in Europe, we try to explain our own difficulties by transforming China (and to a lesser extent, India) into the perfect scapegoat; but what is the reality? (author)
Dynamic diffraction of neutrons on perfect crystals
International Nuclear Information System (INIS)
Abov, Yu.G.; Tyulyusov, A.N.; Elyutin, N.O.
2002-01-01
Theory and experimental results are presented for the phenomena observed in the interaction of a thermal neutron beam with a regular periodic system of nuclei, which constitutes a perfect crystal. Recent studies in this field resulted in the appearance of new trends in the neutron optics, such as neutron interferometry and topography. High angular- and energy-resolution neutron crystal spectrometers were designed and manufactured for the investigation of small-angle and diffractive scattering. Passable new theoretical description of neutron dynamic diffraction and new experiments with neutron beams are discussed [ru
Dynamic diffraction of neutrons on perfect crystals
Abov, Y G; Elyutin, N O
2002-01-01
Theory and experimental results are presented for the phenomena observed in the interaction of a thermal neutron beam with a regular periodic system of nuclei, which constitutes a perfect crystal. Recent studies in this field resulted in the appearance of new trends in the neutron optics, such as neutron interferometry and topography. High angular- and energy-resolution neutron crystal spectrometers were designed and manufactured for the investigation of small-angle and diffractive scattering. Passable new theoretical description of neutron dynamic diffraction and new experiments with neutron beams are discussed
The perfection of loss-free counting
International Nuclear Information System (INIS)
Westphal, G.P.; Lemmel, H.
2008-01-01
Pileup losses in nuclear pulse spectrometry also depend on energy as lower energies produce narrower pulses which in turn have better chances to avoid pulse pileup. Consequently, in our present system individual energy-dependent pileup correction factors are calculated for all events, making it what very probably may be called the first perfect implementation of Loss-Free Counting. Temporal response and quantitative performance of the new system are tested over the whole range of counting rates (up to 106 c/s) and counting losses (up to 99%) by means of short-lived isomeric transitions and a fast rabbit system. (author)
Subgame Perfect Punishment for Repeat Offenders
Winand Emons
2002-01-01
First we show that for wealth-constrained agents who may commit an act twice the optimal sanctions are the offender's entire wealth for the first and zero for the second crime. Then we ask the question whether this decreasing sanction scheme is subgame perfect (time consistent), i.e., does a rent-seeking government stick to this sanction scheme after the first crime has occurred. If the benefit and/or the harm from the crime are not too large, this is indeed the case; otherwise, equal sanctio...
Energy Technology Data Exchange (ETDEWEB)
Zhu, Chen
2015-03-31
An important question for the Carbon Capture, Storage, and Utility program is “can we adequately predict the CO2 plume migration?” For tracking CO2 plume development, the Sleipner project in the Norwegian North Sea provides more time-lapse seismic monitoring data than any other sites, but significant uncertainties still exist for some of the reservoir parameters. In Part I, we assessed model uncertainties by applying two multi-phase compositional simulators to the Sleipner Benchmark model for the uppermost layer (Layer 9) of the Utsira Sand and calibrated our model against the time-lapsed seismic monitoring data for the site from 1999 to 2010. Approximate match with the observed plume was achieved by introducing lateral permeability anisotropy, adding CH4 into the CO2 stream, and adjusting the reservoir temperatures. Model-predicted gas saturation, CO2 accumulation thickness, and CO2 solubility in brine—none were used as calibration metrics—were all comparable with the interpretations of the seismic data in the literature. In Part II & III, we evaluated the uncertainties of predicted long-term CO2 fate up to 10,000 years, due to uncertain reaction kinetics. Under four scenarios of the kinetic rate laws, the temporal and spatial evolution of CO2 partitioning into the four trapping mechanisms (hydrodynamic/structural, solubility, residual/capillary, and mineral) was simulated with ToughReact, taking into account the CO2-brine-rock reactions and the multi-phase reactive flow and mass transport. Modeling results show that different rate laws for mineral dissolution and precipitation reactions resulted in different predicted amounts of trapped CO2 by carbonate minerals, with scenarios of the conventional linear rate law for feldspar dissolution having twice as much mineral trapping (21% of the injected CO2) as scenarios with a Burch-type or Alekseyev et al.–type rate law for feldspar dissolution (11%). So far, most reactive transport modeling (RTM) studies for
Hiby, Lex; Lovell, Phil; Patil, Narendra; Kumar, N Samba; Gopalaswamy, Arjun M; Karanth, K Ullas
2009-06-23
The tiger is one of many species in which individuals can be identified by surface patterns. Camera traps can be used to record individual tigers moving over an array of locations and provide data for monitoring and studying populations and devising conservation strategies. We suggest using a combination of algorithms to calculate similarity scores between pattern samples scanned from the images to automate the search for a match to a new image. We show how using a three-dimensional surface model of a tiger to scan the pattern samples allows comparison of images that differ widely in camera angles and body posture. The software, which is free to download, considerably reduces the effort required to maintain an image catalogue and we suggest it could be used to trace the origin of a tiger skin by searching a central database of living tigers' images for matches to an image of the skin.
A perfectly conducting surface in electrodynamics with Lorentz symmetry breaking
Borges, L. H. C.; Barone, F. A.
2017-10-01
In this paper we consider a model which exhibits explicit Lorentz symmetry breaking due to the presence of a single background vector v^{μ } coupled to the gauge field. We investigate such a theory in the vicinity of a perfectly conducting plate for different configurations of v^{μ }. First we consider no restrictions on the components of the background vector and we treat it perturbatively up to second order. Next, we treat v^{μ } exactly for two special cases: the first one is when it has only components parallel to the plate, and the second one when it has a single component perpendicular to the plate. For all these configurations, the propagator for the gauge field and the interaction force between the plate and a point-like electric charge are computed. Surprisingly, it is shown that the image method is valid in our model and we argue that it is a non-trivial result. We show there arises a torque on the mirror with respect to its positioning in the background field when it interacts with a point-like charge. It is a new effect with no counterpart in theories with Lorentz symmetry in the presence of a perfect mirror.
A perfectly conducting surface in electrodynamics with Lorentz symmetry breaking
Energy Technology Data Exchange (ETDEWEB)
Borges, L.H.C. [UNESP, Campus de Guaratingueta, DFQ, Guaratingueta, SP (Brazil); Barone, F.A. [IFQ, Universidade Federal de Itajuba, Itajuba, MG (Brazil)
2017-10-15
In this paper we consider a model which exhibits explicit Lorentz symmetry breaking due to the presence of a single background vector v{sup μ} coupled to the gauge field. We investigate such a theory in the vicinity of a perfectly conducting plate for different configurations of v{sup μ}. First we consider no restrictions on the components of the background vector and we treat it perturbatively up to second order. Next, we treat v{sup μ} exactly for two special cases: the first one is when it has only components parallel to the plate, and the second one when it has a single component perpendicular to the plate. For all these configurations, the propagator for the gauge field and the interaction force between the plate and a point-like electric charge are computed. Surprisingly, it is shown that the image method is valid in our model and we argue that it is a non-trivial result. We show there arises a torque on the mirror with respect to its positioning in the background field when it interacts with a point-like charge. It is a new effect with no counterpart in theories with Lorentz symmetry in the presence of a perfect mirror. (orig.)
Apnea of prematurity--perfect storm.
Di Fiore, Juliann M; Martin, Richard J; Gauda, Estelle B
2013-11-01
With increased survival of preterm infants as young as 23 weeks gestation, maintaining adequate respiration and corresponding oxygenation represents a clinical challenge in this unique patient cohort. Respiratory instability characterized by apnea and periodic breathing occurs in premature infants because of immature development of the respiratory network. While short respiratory pauses and apnea may be of minimal consequence if oxygenation is maintained, they can be problematic if accompanied by chronic intermittent hypoxemia. Underdevelopment of the lung and the resultant lung injury that occurs in this population concurrent with respiratory instability creates the perfect storm leading to frequent episodes of profound and recurrent hypoxemia. Chronic intermittent hypoxemia contributes to the immediate and long term co-morbidities that occur in this population. In this review we discuss the pathophysiology leading to the perfect storm, diagnostic assessment of breathing instability in this unique population and therapeutic interventions that aim to stabilize breathing without contributing to tissue injury. Copyright © 2013. Published by Elsevier B.V.
Exciton condensation and perfect Coulomb drag.
Nandi, D; Finck, A D K; Eisenstein, J P; Pfeiffer, L N; West, K W
2012-08-23
Coulomb drag is a process whereby the repulsive interactions between electrons in spatially separated conductors enable a current flowing in one of the conductors to induce a voltage drop in the other. If the second conductor is part of a closed circuit, a net current will flow in that circuit. The drag current is typically much smaller than the drive current owing to the heavy screening of the Coulomb interaction. There are, however, rare situations in which strong electronic correlations exist between the two conductors. For example, double quantum well systems can support exciton condensates, which consist of electrons in one well tightly bound to holes in the other. 'Perfect' drag is therefore expected; a steady transport current of electrons driven through one quantum well should be accompanied by an equal current of holes in the other. Here we demonstrate this effect, taking care to ensure that the electron-hole pairs dominate the transport and that tunnelling of charge between the quantum wells, which can readily compromise drag measurements, is negligible. We note that, from an electrical engineering perspective, perfect Coulomb drag is analogous to an electrical transformer that functions at zero frequency.
Kawamura, David H.; Johnson, Philip J.; Moore, Amy M.; Magill, Christina K.; Hunter, Daniel A.; Ray, Wilson Z.; Tung, Thomas HH.; Mackinnon, Susan E.
2010-01-01
The treatment of peripheral nerve injuries with nerve gaps largely consists of autologous nerve grafting utilizing sensory nerve donors. Underlying this clinical practice is the assumption that sensory autografts provide a suitable substrate for motoneuron regeneration, thereby facilitating motor endplate reinnervation and functional recovery. This study examined the role of nerve graft modality on axonal regeneration, comparing motor nerve regeneration through motor, sensory, and mixed nerve isografts in the Lewis rat. A total of 100 rats underwent grafting of the motor or sensory branch of the femoral nerve with histomorphometric analysis performed after 5, 6, or 7 weeks. Analysis demonstrated similar nerve regeneration in motor, sensory, and mixed nerve grafts at all three time points. These data indicate that matching of motor-sensory modality in the rat femoral nerve does not confer improved axonal regeneration through nerve isografts. PMID:20122927
Ozier, Lance
2011-01-01
Pressure for students to produce writing perfection in the classroom often eclipses the emphasis placed on the need for students to practice writing. Occasions for students to choose, challenge, and reflect--to actually risk risking--are too often absent from conversations among students and teachers in countless English classrooms. Tom Romano…
Subwavelength perfect acoustic absorption in membrane-type metamaterials: a geometric perspective
Directory of Open Access Journals (Sweden)
Yang Min
2015-01-01
Full Text Available Perfect absorption of low frequency sound with subwavelength absorbers has always been a challenge, owing to the difficulty in achieving impedance matching and the inherent weak absorption coefficients of materials at low frequencies. Recently it was shown that when a membrane-type resonator’s modes are hybridized through the addition of a thin air-sealed cell with a back reflecting surface, perfect absorption of low frequency acoustic wave can be achieved at a particular tunable frequency. Here we use a geometric perspective, based on the fact that the membrane is very thin and therefore the displacements on both sides of the membrane must be the same, to gain a unified framework for deriving absorption upper bounds as well as for understanding the hybrid resonance and the coherent perfect absorption on the same footing. The latter is another scheme for perfect absorption based on the phase coherence of two counter-propagating waves incident upon the membrane-type resonator. Experiments were carried out to verify some relations predicted by the general framework based on this geometric perspective. Excellent agreement between theory and experiment is seen.
Jiménez, Noé; Romero-García, Vicent; Pagneux, Vincent; Groby, Jean-Philippe
2017-10-19
Perfect, broadband and asymmetric sound absorption is theoretically, numerically and experimentally reported by using subwavelength thickness panels in a transmission problem. The panels are composed of a periodic array of varying crosssection waveguides, each of them being loaded by Helmholtz resonators (HRs) with graded dimensions. The low cut-off frequency of the absorption band is fixed by the resonance frequency of the deepest HR, that reduces drastically the transmission. The preceding HR is designed with a slightly higher resonance frequency with a geometry that allows the impedance matching to the surrounding medium. Therefore, reflection vanishes and the structure is critically coupled. This results in perfect sound absorption at a single frequency. We report perfect absorption at 300 Hz for a structure whose thickness is 40 times smaller than the wavelength. Moreover, this process is repeated by adding HRs to the waveguide, each of them with a higher resonance frequency than the preceding one. Using this frequency cascade effect, we report quasi-perfect sound absorption over almost two frequency octaves ranging from 300 to 1000 Hz for a panel composed of 9 resonators with a total thickness of 11 cm, i.e., 10 times smaller than the wavelength at 300 Hz.
Al Nasr, Kamal; Ranjan, Desh; Zubair, Mohammad; Chen, Lin; He, Jing
2014-01-01
Electron cryomicroscopy is becoming a major experimental technique in solving the structures of large molecular assemblies. More and more three-dimensional images have been obtained at the medium resolutions between 5 and 10 Å. At this resolution range, major α-helices can be detected as cylindrical sticks and β-sheets can be detected as plain-like regions. A critical question in de novo modeling from cryo-EM images is to determine the match between the detected secondary structures from the image and those on the protein sequence. We formulate this matching problem into a constrained graph problem and present an O(Δ(2)N(2)2(N)) algorithm to this NP-Hard problem. The algorithm incorporates the dynamic programming approach into a constrained K-shortest path algorithm. Our method, DP-TOSS, has been tested using α-proteins with maximum 33 helices and α-β proteins up to five helices and 12 β-strands. The correct match was ranked within the top 35 for 19 of the 20 α-proteins and all nine α-β proteins tested. The results demonstrate that DP-TOSS improves accuracy, time and memory space in deriving the topologies of the secondary structure elements for proteins with a large number of secondary structures and a complex skeleton.
A perfect launch of Space Shuttle Discovery
2000-01-01
Space Shuttle Discovery lifts off Launch Pad 39A against a backdrop of xenon lights (just above the orbiter' nose and at left). On the Mobile Launcher Platform beneath, water begins flooding the area for flame and sound control. The perfect on- time liftoff occurred at 7:17 p.m. EDT, sending a crew of seven on the 100th launch in the history of the Shuttle program. Discovery carries a payload that includes the Integrated Truss Structure Z-1, first of 10 trusses that will form the backbone of the Space Station, and the third Pressurized Mating Adapter that will provide a Shuttle docking port for solar array installation on the sixth Station flight and Lab installation on the seventh Station flight. Discovery's landing is expected Oct. 22 at 2:10 p.m. EDT.
A perfect launch viewed across Banana Creek
2000-01-01
Billows of smoke and steam surround Space Shuttle Discovery as it lifts off from Launch Pad 39A on mission STS-92 to the International Space Station. The perfect on-time liftoff occurred at 7:17 p.m. EDT, sending a crew of seven on the 100th launch in the history of the Shuttle program. Discovery carries a payload that includes the Integrated Truss Structure Z-1, first of 10 trusses that will form the backbone of the Space Station, and the third Pressurized Mating Adapter that will provide a Shuttle docking port for solar array installation on the sixth Station flight and Lab installation on the seventh Station flight. Discovery's landing is expected Oct. 22 at 2:10 p.m. EDT.
Field theory of the Eulerian perfect fluid
Ariki, Taketo; Morales, Pablo A.
2018-01-01
The Eulerian perfect-fluid theory is reformulated from its action principle in a pure field-theoretic manner. Conservation of the convective current is no longer imposed by Lin’s constraints, but rather adopted as the central idea of the theory. Our formulation, for the first time, successfully reduces redundant degrees of freedom promoting one half of the Clebsch variables to true dynamical fields. Interactions on these fields allow for the exchange of the convective current of quantities such as mass and charge, which are uniformly understood as the breaking of the underlying symmetry of the force-free fluid. The Clebsch fields play the essential role of exchanging angular momentum with the force field producing vorticity.
The surveyors' quest for perfect alignment
2003-01-01
Photogrammetry of a CMS endcap and part of the hadronic calorimeter.The structure was covered with targets photographed by digital cameras. Perfect alignment.... Although CERN's surveyors do not claim to achieve it, they are constantly striving for it and deploy all necessary means to come as close as they can. In their highly specialised field of large-scale metrology, the solution lies in geodesy and photogrammetry, both of which are based on increasingly sophisticated instruments and systems. In civil engineering, these techniques are used for non-destructive inspection of bridges, dams and other structures, while industrial applications include dimensional verification and deformation measurement in large mechanical assemblies. The same techniques also come into play for the metrology of research tools such as large telescopes and of course, particle accelerators. Particle physics laboratories are especially demanding customers, and CERN has often asked for the impossible. As a result, the alignment metro...
Theory of metasurface based perfect absorbers
Alaee, Rasoul; Albooyeh, Mohammad; Rockstuhl, Carsten
2017-12-01
Based on an analytic approach, we present a theoretical review on the absorption, scattering, and extinction of both dipole scatterers and regular arrays composed of such scatterers i.e. metasurfaces. Besides offering a tutorial by outlining the maximum absorption limit for electrically/magnetically resonant dipole particles/metasurfaces, we give an educative analytical approach to their analysis. Moreover, we put forward the analysis of two known alternatives in providing perfect absorbers out of electrically and or magnetically resonant metasurfaces; one is based on the simultaneous presence of both electric and magnetic responses in so called Huygens metasurfaces while the other is established upon the presence of a back reflector in so called Salisbury absorbers. Our work is supported by several numerical examples to clarify the discussions in each stage.
Broadband Reflectionless Metasheets: Frequency-Selective Transmission and Perfect Absorption
Directory of Open Access Journals (Sweden)
V. S. Asadchy
2015-07-01
Full Text Available Energy of propagating electromagnetic waves can be fully absorbed in a thin lossy layer, but only in a narrow frequency band, as follows from the causality principle. On the other hand, it appears that there are no fundamental limitations on broadband matching of thin resonant absorbing layers. However, known thin absorbers produce significant reflections outside of the resonant absorption band. In this paper, we explore possibilities to realize a thin absorbing layer that produces no reflected waves in a very wide frequency range, while the transmission coefficient has a narrow peak of full absorption. Here we show, both theoretically and experimentally, that a thin resonant absorber, invisible in reflection in a very wide frequency range, can be realized if one and the same resonant mode of the absorbing array unit cells is utilized to create both electric and magnetic responses. We test this concept using chiral particles in each unit cell, arranged in a periodic planar racemic array, utilizing chirality coupling in each unit cell but compensating the field coupling at the macroscopic level. We prove that the concept and the proposed realization approach also can be used to create nonreflecting layers for full control of transmitted fields. Our results can have a broad range of potential applications over the entire electromagnetic spectrum including, for example, perfect ultracompact wave filters and selective multifrequency sensors.
Robust weighted scan matching with quadtrees
Visser, A.; Slamet, B.A.; Pfingsthorn, M.
2009-01-01
This paper presents the improvement of the robustness and accuracy of the weighted scan matching algorithm matching against the union of earlier acquired scans. The approach allows to reduce the correspondence error, which is explicitly modeled in the weighted scan matching algorithm, by providing a
DEFF Research Database (Denmark)
Gregoriussen, Angelica Maria Mohr; Bohr, Henrik Georg
2017-01-01
Donor-specific blood transfusion (DST) can lead to significant prolongation of allograft survival in experimental animal models and sometimes human recipients of solid organs. The mechanisms responsible for the beneficial effect on graft survival have been a topic of research and debate for decades...... during the course of tolerance induction. Based on the immunological status of the recipients, we suggest that one H2-haplotype-matched self-specific Tregs derived from the transfusion blood can be activated and multiply in the host by binding to antigen-presenting cells presenting allopeptides...
... for Kids ▸ Stinging Insect Matching Game Share | Stinging Insect Matching Game Stinging insects can ruin summer fun for those who are ... the difference between the different kinds of stinging insects in order to keep your summer safe and ...
Bianchi type-I massive string magnetized barotropic perfect ﬂuid
Indian Academy of Sciences (India)
Bianchi type-I massive string cosmological model for perfect ﬂuid distribution in the presence of magnetic ﬁeld is investigated in Rosen's [Gen. Relativ. Gravit. 4, 435 (1973)] bimetric theory of gravitation. To obtain the deterministic model in terms of cosmic time, we have used the condition A = ( B C ) n , where n is a constant, ...
Inhomogeneous generalizations of Bianchi Type VIh universes with stiff perfect fluid and radiation
Roy, S. R.; Prasad, A.
1995-03-01
Families of inhomogeneous models filled with a stiff perfect fluid and radiation have been derived in which there is no flow of total momentum. The models are generalizations of those of Bianchi Type VIh and are discussed for some particular forms of the arbitrary functions appearing in them.
Nguyen, T T; Biadillah, Y; Mongrain, R; Brunette, J; Tardif, J C; Bertrand, O F
2004-08-01
In this work, we propose a simple method to simultaneously match the refractive index and kinematic viscosity of a circulating blood analog in hydraulic models for optical flow measurement techniques (PIV, PMFV, LDA, and LIF). The method is based on the determination of the volumetric proportions and temperature at which two transparent miscible liquids should be mixed to reproduce the targeted fluid characteristics. The temperature dependence models are a linear relation for the refractive index and an Arrhenius relation for the dynamic viscosity of each liquid. Then the dynamic viscosity of the mixture is represented with a Grunberg-Nissan model of type 1. Experimental tests for acrylic and blood viscosity were found to be in very good agreement with the targeted values (measured refractive index of 1.486 and kinematic viscosity of 3.454 milli-m2/s with targeted values of 1.47 and 3.300 milli-m2/s).
Plasma focus matching conditions
International Nuclear Information System (INIS)
Soliman, H.M.; Masoud, M.M.; Elkhalafawy, T.A.
1988-01-01
A snow-plough and slug models have been used to obtain the optimum matching conditions of the plasma in the focus. The dimensions of the plasma focus device are, inner electrode radius = 2 cm, outer electrode radius = 5.5 cm, and its length = 8 cm. It was found that the maximum magnetic energy of 12.26 kJ has to be delivered to plasma focus whose density is 10 19 /cm 3 at focusing time of 2.55 μs and with total external inductance of 24.2 n H. The same method is used to evaluate the optimum matching conditions for the previous coaxial discharge system which had inner electrode radius = 1.6 cm, outer electrode radius = 3.3 cm and its length = 31.5 cm. These conditions are charging voltage = 12 kV, capacity of the condenser bank = 430 μf, plasma focus density = 10 19 /cm 3 focusing time = 8 μs and total external inductance = 60.32 n H.3 fig., 2 tab
A Template Matching Method of Wideband Sonar Detection
Energy Technology Data Exchange (ETDEWEB)
Chen, J Y; Zhong, X P; Feng, X Z [College of Mechatronics Engineering and Automation National University of Defense Technology ChangSha, HuNan (China)
2006-10-15
Advances in computer memory, computation speed, and transducer bandwidth have made possible higher Time-Bandwidth product (TB) transmit signals and will bring out higher resolutions. In this paper a new method is proposed to estimation Doppler velocity base on correlation analysis and mode matching in wideband condition instead of wideband matched filter. Paper use mode-matching principle to search appropriate scaled factor matrix. Simulation showing this method has well restrains noise capability and perfect calculation stability; the amount of compute can be decreased greatly by scaled factor matrix computed in advance.
A Template Matching Method of Wideband Sonar Detection
International Nuclear Information System (INIS)
Chen, J Y; Zhong, X P; Feng, X Z
2006-01-01
Advances in computer memory, computation speed, and transducer bandwidth have made possible higher Time-Bandwidth product (TB) transmit signals and will bring out higher resolutions. In this paper a new method is proposed to estimation Doppler velocity base on correlation analysis and mode matching in wideband condition instead of wideband matched filter. Paper use mode-matching principle to search appropriate scaled factor matrix. Simulation showing this method has well restrains noise capability and perfect calculation stability; the amount of compute can be decreased greatly by scaled factor matrix computed in advance
The Perfect Glass Paradigm: Disordered Hyperuniform Glasses Down to Absolute Zero.
Zhang, G; Stillinger, F H; Torquato, S
2016-11-28
Rapid cooling of liquids below a certain temperature range can result in a transition to glassy states. The traditional understanding of glasses includes their thermodynamic metastability with respect to crystals. However, here we present specific examples of interactions that eliminate the possibilities of crystalline and quasicrystalline phases, while creating mechanically stable amorphous glasses down to absolute zero temperature. We show that this can be accomplished by introducing a new ideal state of matter called a "perfect glass". A perfect glass represents a soft-interaction analog of the maximally random jammed (MRJ) packings of hard particles. These latter states can be regarded as the epitome of a glass since they are out of equilibrium, maximally disordered, hyperuniform, mechanically rigid with infinite bulk and shear moduli, and can never crystallize due to configuration-space trapping. Our model perfect glass utilizes two-, three-, and four-body soft interactions while simultaneously retaining the salient attributes of the MRJ state. These models constitute a theoretical proof of concept for perfect glasses and broaden our fundamental understanding of glass physics. A novel feature of equilibrium systems of identical particles interacting with the perfect-glass potential at positive temperature is that they have a non-relativistic speed of sound that is infinite.
Feedback as the source of imperfection in lossy perfect lenses
Rosenblatt, Gilad; Bartal, Guy; Orenstein, Meir
2016-02-01
The major barrier to realizing a perfect lens with left-handed materials is perceived to be their intrinsic loss. Here we show that only specific designs of perfect lenses are limited by loss—those in which material loss is translated to internal feedback. The asymptotically uniform transmission required for perfect lensing is hindered by such feedback, which generates resonances that lead to a spatial cutoff in the lens transmission. Moreover, uniform transmission and its resonant deterioration stem from completely separate classes of modal excitations. A perfect lens made of lossy left-handed materials is therefore not forbidden in principle. Pursuing perfect lens designs that avoid internal feedback offers a path towards realization of practical perfect lenses.
Dohn, Anders; Garza-Villarreal, Eduardo A; Heaton, Pamela; Vuust, Peter
2012-01-01
Perfect pitch, also known as absolute pitch (AP), refers to the rare ability to identify or produce a musical tone correctly without the benefit of an external reference. AP is often considered to reflect musical giftedness, but it has also been associated with certain disabilities due to increased prevalence of AP in individuals with sensory and developmental disorders. Here, we determine whether individual autistic traits are present in people with AP. We quantified subclinical levels of autism traits using the Autism-Spectrum Quotient (AQ) in three matched groups of subjects: 16 musicians with AP (APs), 18 musicians without AP (non-APs), and 16 non-musicians. In addition, we measured AP ability by a pitch identification test with sine wave tones and piano tones. We found a significantly higher degree of autism traits in APs than in non-APs and non-musicians, and autism scores were significantly correlated with pitch identification scores (r = .46, p = .003). However, our results showed that APs did not differ from non-APs on diagnostically crucial social and communicative domain scores and their total AQ scores were well below clinical thresholds for autism. Group differences emerged on the imagination and attention switching subscales of the AQ. Thus, whilst these findings do link AP with autism, they also show that AP ability is most strongly associated with personality traits that vary widely within the normal population.
Coherent perfect absorption and reflection in slow-light waveguides.
Gutman, Nadav; Sukhorukov, Andrey A; Chong, Y D; de Sterke, C Martijn
2013-12-01
We identify a family of unusual slow-light modes occurring in lossy multimode grating waveguides, for which either the forward or backward mode components, or both, are degenerate. In the fully degenerate case, the response can be modulated between coherent perfect absorption (zero reflection) and perfect reflection by varying the wave amplitudes in a uniform input waveguide. The perfectly absorbed wave has anomalously short absorption length, scaling as the inverse one-third power of the absorptivity.
Directory of Open Access Journals (Sweden)
D. Noviyanti
2016-07-01
Full Text Available Penelitian ini bertujuan untuk mengetahui pengaruh penggunaan model cooperative learning type make-a-match dengan media evidence card terhadap hasil belajar kimia materi larutan asam-basa. Populasi penelitian adalah siswa kelas XI IPA. Pengambilan sampel dilakukan dengan sampling jenuh dengan XIA1 sebagai kelas kontrol dan XIA2 sebagai kelas eksperimen. Berdasarkan uji t dua pihak dihasilkan thitung(4,0293> t1abe1(1,9925 yang berarti ada perbedaan yang signifikan, sedangkan uji t satu pihak kanan thitun9(4,0293>t1abe1(1,9925 yang berarti rata-rata hasil belajar kognitif kelas eksperimen lebih baik daripada kelas kontrol. N-gain kelas eksperimen (0,71 lebih baik daripada kelas kontrol (0,52. Hal ini menunjukkan bahwa penggunakan model Coperative Learning type make-a-match dengan media evidence card mempengaruhi hasil belajar kimia materi larutan asam-basa sebesar 28,99% sehingga guru hendaknya berupaya menerapkan model pembelajaran ini pada materi lain.The study was aimed to determine the effect of the use of cooperative learning model of type make-a-card match with the evidence card media on chemistry learning outcomes of acid-base solution. The population was students of Science class XI. Sampling was performed by saturated sampling with XIA 1 as the control and XIA2 as the experiment class. The two sides t test produced tcount (4.0293> Trable (1.9925 which means there was a significant difference, while the one right side t test produced tcount (4.0293> T Table (1.9925, which means that the average cognitive learning outcome of the experimental class was better than that of the control class. N-gain of the experimental class (0.71 was better than that of the control class (0.52. This showed that the use of this model affected the learning outcomes of acid-base solution of 28.99%, so teachers should try to apply this learning model on another matter.
Directory of Open Access Journals (Sweden)
Will Jones
2017-08-01
Full Text Available Design of matching systems between refugees and states or local areas is emerging as one of the most promising solutions to problems in refugee resettlement. We describe the basics of two-sided matching theory used in a number of allocation problems, such as school choice, where both sides need to agree to the match. We then explain how these insights can be applied to international refugee matching in the context of the European Union and examine how refugee matching might work within the United Kingdom, Canada, and the United States.
Directory of Open Access Journals (Sweden)
J. Parajka
2009-02-01
Full Text Available This study compares ERS scatterometer top soil moisture observations with simulations of a dual layer conceptual hydrologic model. The comparison is performed for 148 Austrian catchments in the period 1991–2000. On average, about 5 to 7 scatterometer images per month with a mean spatial coverage of about 37% are available. The results indicate that the agreement between the two top soil moisture estimates changes with the season and the weight given to the scatterometer in hydrologic model calibration. The hydrologic model generally simulates larger top soil moisture values than are observed by the scatterometer. The differences tend to be smaller for lower altitudes and the winter season. The average correlation between the two estimates is more than 0.5 in the period from July to October, and about 0.2 in the winter months, depending on the period and calibration setting. Using both ERS scatterometer based soil moisture and runoff for model calibration provides more robust model parameters than using either of these two sources of information.
Parajka, J.; Naeimi, V.; Blöschl, G.; Komma, J.
2009-02-01
This study compares ERS scatterometer top soil moisture observations with simulations of a dual layer conceptual hydrologic model. The comparison is performed for 148 Austrian catchments in the period 1991-2000. On average, about 5 to 7 scatterometer images per month with a mean spatial coverage of about 37% are available. The results indicate that the agreement between the two top soil moisture estimates changes with the season and the weight given to the scatterometer in hydrologic model calibration. The hydrologic model generally simulates larger top soil moisture values than are observed by the scatterometer. The differences tend to be smaller for lower altitudes and the winter season. The average correlation between the two estimates is more than 0.5 in the period from July to October, and about 0.2 in the winter months, depending on the period and calibration setting. Using both ERS scatterometer based soil moisture and runoff for model calibration provides more robust model parameters than using either of these two sources of information.
Directory of Open Access Journals (Sweden)
Dejan Trifunovic
2017-08-01
Full Text Available In this paper, we present the problem of matching students to schools by using different matching mechanisms. This market is specific since public schools are free and the price mechanism cannot be used to determine the optimal allocation of children in schools. Therefore, it is necessary to use different matching algorithms that mimic the market mechanism and enable us to determine the core of the cooperative game. In this paper, we will determine that it is possible to apply cooperative game theory in matching problems. This review paper is based on illustrative examples aiming to compare matching algorithms in terms of the incentive compatibility, stability and efficiency of the matching. In this paper we will present some specific problems that may occur in matching, such as improving the quality of schools, favoring minority students, the limited length of the list of preferences and generating strict priorities from weak priorities.
Best matching theory & applications
Moghaddam, Mohsen
2017-01-01
Mismatch or best match? This book demonstrates that best matching of individual entities to each other is essential to ensure smooth conduct and successful competitiveness in any distributed system, natural and artificial. Interactions must be optimized through best matching in planning and scheduling, enterprise network design, transportation and construction planning, recruitment, problem solving, selective assembly, team formation, sensor network design, and more. Fundamentals of best matching in distributed and collaborative systems are explained by providing: § Methodical analysis of various multidimensional best matching processes § Comprehensive taxonomy, comparing different best matching problems and processes § Systematic identification of systems’ hierarchy, nature of interactions, and distribution of decision-making and control functions § Practical formulation of solutions based on a library of best matching algorithms and protocols, ready for direct applications and apps development. Design...
Modern problems of perfection of elite light athletic sportsmen’s technical skillfulness perfection
Directory of Open Access Journals (Sweden)
A.V. Kolot
2016-04-01
Full Text Available Purpose: perfection of elite sportsmen’s technical skillfulness in competition kinds of light athletic. Material: the data of more than 60 literature sources were systemized. Expert questioning of 36 coaches, having experience of work with elite sportsmen, was carried out; documents of training process planning were analyzed as well as sportsmen’s diaries (n=244. Results: we have presented main principles of sportsmen’s technical skillfulness perfection and elucidated characteristics of technical training methodic. We have determined main priorities of technical training building for light athletes at every stage of many years’ perfection. Dynamic of competition practice volume has been found as well as main requirements to selection of training means of technical orientation. The data of bio-mechanical criteria of sportsmen’s technical skillfulness assessment have been supplemented. Conclusions: effectiveness of sportsmen’s training methodic is determined by realization of previous stages’ technical potential in final competition results. It can be achieved by determination of means of and methods of different orientation rational correlation.
Modern problems of perfection of elite light athletic sportsmen’s technical skillfulness perfection
Directory of Open Access Journals (Sweden)
Kolot A.V.
2016-02-01
Full Text Available Purpose: perfection of elite sportsmen’s technical skillfulness in competition kinds of light athletic. Material: the data of more than 60 literature sources were systemized. Expert questioning of 36 coaches, having experience of work with elite sportsmen, was carried out; documents of training process planning were analyzed as well as sportsmen’s diaries (n=244. Results: we have presented main principles of sportsmen’s technical skillfulness perfection and elucidated characteristics of technical training methodic. We have determined main priorities of technical training building for light athletes at every stage of many years’ perfection. Dynamic of competition practice volume has been found as well as main requirements to selection of training means of technical orientation. The data of bio-mechanical criteria of sportsmen’s technical skillfulness assessment have been supplemented. Conclusions: effectiveness of sportsmen’s training methodic is determined by realization of previous stages’ technical potential in final competition results. It can be achieved by determination of means of and methods of different orientation rational correlation.
International Nuclear Information System (INIS)
Harrop, L.P.
1982-02-01
Failure rates for non-nuclear pressure vessel populations are often regarded as showing a decrease with time. Empirical evidence can be cited which supports this view. On the other hand theoretical predictions of PWR type reactor pressure vessel failure rates have shown an increasing failure rate with time. It is shown that these two situations are not necessarily incompatible. If adjustments are made to the input data of the theoretical model to treat a non-nuclear pressure vessel population, the model can produce a failure rate which decreases with time. These adjustments are explained and the results obtained are shown. (author)
An Implementation of Bigraph Matching
DEFF Research Database (Denmark)
Glenstrup, Arne John; Damgaard, Troels Christoffer; Birkedal, Lars
We describe a provably sound and complete matching algorithm for bigraphical reactive systems. The algorithm has been implemented in our BPL Tool, a first implementation of bigraphical reactive systems. We describe the tool and present a concrete example of how it can be used to simulate a model ...... of a mobile phone system in a bigraphical representation of the polyadic π calculus.......We describe a provably sound and complete matching algorithm for bigraphical reactive systems. The algorithm has been implemented in our BPL Tool, a first implementation of bigraphical reactive systems. We describe the tool and present a concrete example of how it can be used to simulate a model...
van der Laken, P.A.; Bakk, Zsuzsa; Giagkoulas, Vasileios; van Leeuwen, Linda; Bongenaar, Esther
2018-01-01
Researchers frequently rely on general linear models (GLMs) to investigate the impact of human resource management (HRM) decisions. However, the structure of organizations and recent technological advancements in the measurement of HRM processes cause contemporary HR data to be hierarchical and/or
Gentry, R V
2003-01-01
Accompanying disproof of the F-L expansion paradigm eliminates the basis for expansion redshifts, which in turn eliminates the basis for the Cosmological Principle. The universe is not the same everywhere. Instead the spherical symmetry of the cosmos demanded by the Hubble redshift relation proves the universe is isotropic about a nearby universal Center. This is the foundation of the relatively new Cosmic Center Universe (CCU) model, which accounts for, explains, or predicts: (i) The Hubble redshift relation, (ii) a CBR redshift relation that fits all current CBR measurements, (iii) the recently discovered velocity dipole distribution of radiogalaxies, (iv) the well-known time dilation of SNeIa light curves, (v) the Sunyaev-Zeldovich thermal effect, (vi) Olber's paradox, (vii) SN dimming for z 1 an enhanced brightness that fits SN 1997ff measurements, (ix) the existence of extreme redshift (z > 10) objects which, when observed, will further distinguish it from the big bang. The CCU model also plausibly expl...
Practice makes two hemispheres almost perfect.
Cherbuin, Nicolas; Brinkman, Cobie
2005-08-01
Some tasks produce a performance advantage for conditions that require the processing of stimuli in two visual fields compared to conditions where single hemifield processing is sufficient. This advantage, however, disappears with practice. Although no definitive evidence yet exists, there are several possible mechanisms that might lead to improved performance of within- compared to across-hemisphere processing with practice. These include a shift from a more demanding, algorithmic strategy to a less demanding memory-retrieval strategy (e.g., [G. Logan, Toward an instance theory of automatisation. Psych. Rev. 95 (1988) 492-527]), as discussed by Weissman and Compton [D.H. Weissman, R.J. Compton, Practice makes a hemisphere perfect: the advantage of interhemispheric recruitment is eliminated with practice. Laterality, 8 (4) (2003) 361-375], and/or a more generalised practice effect [K. Kirsner, C. Speelman, Skill acquisition and repetition priming: one principle, many processes? J. Exp. Psychol., Learn. Mem. Cogn., 22 (1996) 563-575]. Contrary to Weissman and Compton findings, our results suggest that although single-hemisphere performance improves with practice, bi-hemispheric performance also improves substantially. Furthermore, these effects do not appear to be due to a shift in strategy but rather due to a general practice effect.
The swimming of a perfect deforming helix
Koens, Lyndon; Zhang, Hang; Mourran, Ahmed; Lauga, Eric
2017-11-01
Many bacteria rotate helical flagellar filaments in order to swim. When at rest or rotated counter-clockwise these flagella are left handed helices but they undergo polymorphic transformations to right-handed helices when the motor is reversed. These helical deformations themselves can generate motion, with for example Rhodobacter sphaeroides using the polymorphic transformation of the flagellum to generate rotation, or Spiroplasma propagating a change of helix handedness across its body's length to generate forward motion. Recent experiments reported on an artificial helical microswimmer generating motion without a propagating change in handedness. Made of a temperature sensitive gel, these swimmers moved by changing the dimensions of the helix in a non-reciprocal way. Inspired by these results and helix's ubiquitous presence in the bacterial world, we investigate how a deforming helix moves within a viscous fluid. Maintaining a single handedness along its entire length, we discuss how a perfect deforming helix can create a non-reciprocal swimming stroke, identify its principle directions of motion, and calculate the swimming kinematics asymptotically.
Perfect crystal interferometer and its applications
Energy Technology Data Exchange (ETDEWEB)
Hasegawa, Yuji [Atominstitut der Oesterreichischen Universitaeten, Vienna (Austria)
1996-08-01
The interferometry with angstrom scale wavelength has developed steadily, and various types of interferometers have been investigated. Among them, LLL interferometers are widely used. The first neutron interferometry was achieved in 1962 by Maier-Leibnitz et al. A new type of neutron interferometers was constructed with a perfect crystal, and experimentally performed in 1974 by Rauch et al. The precise measurements with LLL neutron interferometers were performed on scattering length, gravitational effect, coherence, Fizeau effects, spin superposition, complementarity, and post-selection effects. Since the early stage of quantum physics, the double-slit experiment has served as the example of the epistemologically strange features of quantum phenomena, and its course of study is described. The time-delayed interferometry with nuclear resonant scattering of synchrotron radiation and phase transfer in time-delayed interferometry with nuclear resonant scattering were experimented, and are briefly reported. A geometric phase factor was derived for a split beam experiment as an example of cyclic evolution. The geometric phase was observed with a two-loop neutron interferometer. All the experimental results showed complete agreement with the theoretical treatment. (K.I.)
Probabilistic seismic history matching using binary images
Davolio, Alessandra; Schiozer, Denis Jose
2018-02-01
Currently, the goal of history-matching procedures is not only to provide a model matching any observed data but also to generate multiple matched models to properly handle uncertainties. One such approach is a probabilistic history-matching methodology based on the discrete Latin Hypercube sampling algorithm, proposed in previous works, which was particularly efficient for matching well data (production rates and pressure). 4D seismic (4DS) data have been increasingly included into history-matching procedures. A key issue in seismic history matching (SHM) is to transfer data into a common domain: impedance, amplitude or pressure, and saturation. In any case, seismic inversions and/or modeling are required, which can be time consuming. An alternative to avoid these procedures is using binary images in SHM as they allow the shape, rather than the physical values, of observed anomalies to be matched. This work presents the incorporation of binary images in SHM within the aforementioned probabilistic history matching. The application was performed with real data from a segment of the Norne benchmark case that presents strong 4D anomalies, including softening signals due to pressure build up. The binary images are used to match the pressurized zones observed in time-lapse data. Three history matchings were conducted using: only well data, well and 4DS data, and only 4DS. The methodology is very flexible and successfully utilized the addition of binary images for seismic objective functions. Results proved the good convergence of the method in few iterations for all three cases. The matched models of the first two cases provided the best results, with similar well matching quality. The second case provided models presenting pore pressure changes according to the expected dynamic behavior (pressurized zones) observed on 4DS data. The use of binary images in SHM is relatively new with few examples in the literature. This work enriches this discussion by presenting a new
The perfect man in the literary opus of John Climacus and Ibn Arabi
Directory of Open Access Journals (Sweden)
Rašić Dunja
2015-01-01
Full Text Available In search of the perfect man of the Islamic and Christian mysticisms, this paper also discusses the nature of mystical knowledge, to whose domain the perfect man, as the highest model of human existence and spiritual life, indisputably belongs. This study belongs to the philosophical discipline of comparative philosophy. Hence, searching for the lost paradise of human existence, still remembering the taste of bliss of residence filled only with infinite happiness, this paper will consider the extent to which the methodology of Paul Masson-Oursel and Henry Corbin, as two well-known comparative philosophy research methods can try to measure their strength with cryptic teachings of mysticism.
QCD next-to-leading order predictions matched to parton showers for vector-like quark models
Fuks, Benjamin
2017-02-27
Vector-like quarks are featured by a wealth of beyond the Standard Model theories and are consequently an important goal of many LHC searches for new physics. Those searches, as well as most related phenomenological studies, however rely on predictions evaluated at the leading-order accuracy in QCD and consider well-defined simplified benchmark scenarios. Adopting an effective bottom-up approach, we compute next-to-leading-order predictions for vector-like-quark pair-production and single production in association with jets, with a weak or with a Higgs boson in a general new physics setup. We additionally compute vector-like-quark contributions to the production of a pair of Standard Model bosons at the same level of accuracy. For all processes under consideration, we focus both on total cross sections and on differential distributions, most these calculations being performed for the first time in our field. As a result, our work paves the way to precise extraction of experimental limits on vector-like quarks...
QCD next-to-leading-order predictions matched to parton showers for vector-like quark models.
Fuks, Benjamin; Shao, Hua-Sheng
2017-01-01
Vector-like quarks are featured by a wealth of beyond the Standard Model theories and are consequently an important goal of many LHC searches for new physics. Those searches, as well as most related phenomenological studies, however, rely on predictions evaluated at the leading-order accuracy in QCD and consider well-defined simplified benchmark scenarios. Adopting an effective bottom-up approach, we compute next-to-leading-order predictions for vector-like-quark pair production and single production in association with jets, with a weak or with a Higgs boson in a general new physics setup. We additionally compute vector-like-quark contributions to the production of a pair of Standard Model bosons at the same level of accuracy. For all processes under consideration, we focus both on total cross sections and on differential distributions, most these calculations being performed for the first time in our field. As a result, our work paves the way to precise extraction of experimental limits on vector-like quarks thanks to an accurate control of the shapes of the relevant observables and emphasise the extra handles that could be provided by novel vector-like-quark probes never envisaged so far.
Paweł Strawiński
2011-01-01
Matched sampling is a methodology used to estimate treatment effects. A caliper mechanism is used to achieve better similarity among matched pairs. We investigate finite sample properties of matching with calipers and propose a slight modification to the existing mechanism. The simulation study compares the performance of both methods and shows that a standard caliper performs well only in case of constant treatment or uniform propensity score distribution. Secondly, in a case of non-uniform ...
The Ideology of the Perfect Dictionary: How Efficient Can a ...
African Journals Online (AJOL)
There is no perfect student. Language learners, for whom dictionaries are of great importance, seek user-friendly material which will improve both their fluency in and understanding of the target language, and embed acquired lexis in their long-term memory. Lexicographers, in their search for perfection and in compliance ...
Tie-breaking in games of perfect information
DEFF Research Database (Denmark)
Tranæs, Torben
1998-01-01
The paper suggests that ties in an extensive form game have strategic implications if they represent credible threats or promises. We consider a subset of subgame-perfect Nash equilibria obtained by breaking ties according to their strategic implications, and show that the subset is nonempty for ...... for finite extensive form games of perfect information....
The Ideology of the Perfect Dictionary: How Efficient Can a ...
African Journals Online (AJOL)
rbr
curiosities, archaisms and other vestiges from the past conserved in dictionaries. Is the concept of a perfect dictionary a reality or an ideal? There is no perfect student. Language learners, for whom dictionaries are of great importance, seek user-friendly material which will improve both their fluency in and understanding of ...
On some properties of Einstein equations with the perfect fluid energy-momentum tensor
International Nuclear Information System (INIS)
Biesiada, M.; Szydlowski, M.; Szczesny, J.
1989-01-01
We discuss the symmetries of Einstein equations with the perfect fluid energy momentum tensor. We show that the symmetries inherited from vacuum equations enforce the equation of state in the form p p 0 = γρ which is the most often used one and contains models with the cosmological constant. 9 refs. (author)
Lattice fluid dynamics from perfect discretizations of continuum flows
International Nuclear Information System (INIS)
Katz, E.; Wiese, U.
1998-01-01
We use renormalization group methods to derive equations of motion for large scale variables in fluid dynamics. The large scale variables are averages of the underlying continuum variables over cubic volumes and naturally exist on a lattice. The resulting lattice dynamics represents a perfect discretization of continuum physics, i.e., grid artifacts are completely eliminated. Perfect equations of motion are derived for static, slow flows of incompressible, viscous fluids. For Hagen-Poiseuille flow in a channel with a square cross section the equations reduce to a perfect discretization of the Poisson equation for the velocity field with Dirichlet boundary conditions. The perfect large scale Poisson equation is used in a numerical simulation and is shown to represent the continuum flow exactly. For nonsquare cross sections one can use a numerical iterative procedure to derive flow equations that are approximately perfect. copyright 1998 The American Physical Society
Vanfretti, Luigi; Olsen, Svein H; Arava, V S Narasimham; Laera, Giuseppe; Bidadfar, Ali; Rabuzin, Tin; Jakobsen, Sigurd H; Lavenius, Jan; Baudette, Maxime; Gómez-López, Francisco J
2017-04-01
This article presents an open data repository, the methodology to generate it and the associated data processing software developed to consolidate an hourly snapshot historical data set for the year 2015 to an equivalent Nordic power grid model (aka Nordic 44), the consolidation was achieved by matching the model׳s physical response w.r.t historical power flow records in the bidding regions of the Nordic grid that are available from the Nordic electricity market agent, Nord Pool. The model is made available in the form of CIM v14, Modelica and PSS/E (Siemens PTI) files. The Nordic 44 model in Modelica and PSS/E were first presented in the paper titled "iTesla Power Systems Library (iPSL): A Modelica library for phasor time-domain simulations" (Vanfretti et al., 2016) [1] for a single snapshot. In the digital repository being made available with the submission of this paper (SmarTSLab_Nordic44 Repository at Github, 2016) [2], a total of 8760 snapshots (for the year 2015) that can be used to initialize and execute dynamic simulations using tools compatible with CIM v14, the Modelica language and the proprietary PSS/E tool are provided. The Python scripts to generate the snapshots (processed data) are also available with all the data in the GitHub repository (SmarTSLab_Nordic44 Repository at Github, 2016) [2]. This Nordic 44 equivalent model was also used in iTesla project (iTesla) [3] to carry out simulations within a dynamic security assessment toolset (iTesla, 2016) [4], and has been further enhanced during the ITEA3 OpenCPS project (iTEA3) [5]. The raw, processed data and output models utilized within the iTesla platform (iTesla, 2016) [4] are also available in the repository. The CIM and Modelica snapshots of the "Nordic 44" model for the year 2015 are available in a Zenodo repository.
Briceño, Javier; Cruz-Ramírez, Manuel; Prieto, Martín; Navasa, Miguel; Ortiz de Urbina, Jorge; Orti, Rafael; Gómez-Bravo, Miguel-Ángel; Otero, Alejandra; Varo, Evaristo; Tomé, Santiago; Clemente, Gerardo; Bañares, Rafael; Bárcena, Rafael; Cuervas-Mons, Valentín; Solórzano, Guillermo; Vinaixa, Carmen; Rubín, Angel; Colmenero, Jordi; Valdivieso, Andrés; Ciria, Rubén; Hervás-Martínez, César; de la Mata, Manuel
2014-11-01
There is an increasing discrepancy between the number of potential liver graft recipients and the number of organs available. Organ allocation should follow the concept of benefit of survival, avoiding human-innate subjectivity. The aim of this study is to use artificial-neural-networks (ANNs) for donor-recipient (D-R) matching in liver transplantation (LT) and to compare its accuracy with validated scores (MELD, D-MELD, DRI, P-SOFT, SOFT, and BAR) of graft survival. 64 donor and recipient variables from a set of 1003 LTs from a multicenter study including 11 Spanish centres were included. For each D-R pair, common statistics (simple and multiple regression models) and ANN formulae for two non-complementary probability-models of 3-month graft-survival and -loss were calculated: a positive-survival (NN-CCR) and a negative-loss (NN-MS) model. The NN models were obtained by using the Neural Net Evolutionary Programming (NNEP) algorithm. Additionally, receiver-operating-curves (ROC) were performed to validate ANNs against other scores. Optimal results for NN-CCR and NN-MS models were obtained, with the best performance in predicting the probability of graft-survival (90.79%) and -loss (71.42%) for each D-R pair, significantly improving results from multiple regressions. ROC curves for 3-months graft-survival and -loss predictions were significantly more accurate for ANN than for other scores in both NN-CCR (AUROC-ANN=0.80 vs. -MELD=0.50; -D-MELD=0.54; -P-SOFT=0.54; -SOFT=0.55; -BAR=0.67 and -DRI=0.42) and NN-MS (AUROC-ANN=0.82 vs. -MELD=0.41; -D-MELD=0.47; -P-SOFT=0.43; -SOFT=0.57, -BAR=0.61 and -DRI=0.48). ANNs may be considered a powerful decision-making technology for this dataset, optimizing the principles of justice, efficiency and equity. This may be a useful tool for predicting the 3-month outcome and a potential research area for future D-R matching models. Copyright © 2014 European Association for the Study of the Liver. Published by Elsevier B.V. All rights
A Phase Matching, Adiabatic Accelerator
Energy Technology Data Exchange (ETDEWEB)
Lemery, Francois [Hamburg U.; Flöttmann, Klaus [DESY; Kärtner, Franz [CFEL, Hamburg; Piot, Philippe [Northern Illinois U.
2017-05-01
Tabletop accelerators are a thing of the future. Reducing their size will require scaling down electromagnetic wavelengths; however, without correspondingly high field gradients, particles will be more susceptible to phase-slippage – especially at low energy. We investigate how an adiabatically-tapered dielectric-lined waveguide could maintain phase-matching between the accelerating mode and electron bunch. We benchmark our simple model with CST and implement it into ASTRA; finally we provide a first glimpse into the beam dynamics in a phase-matching accelerator.
Su, Tung-Ching
2017-06-01
Linear regression models are a popular choice for the relationships between water quality parameters and bands (or band ratios) of remote sensing data. However, this research regards the phenomena of mixed pixels, specular reflection, and water fluidity as the challenges to establish a robust regression model. Based on the data of measurements in situ and remote sensing data, this study presents an enumeration-based algorithm, called matching pixel by pixel (MPP), and tests its performance in an empirical model of water quality mapping. Four small reservoirs, which cover a mere several hundred-thousand m2, in Kinmen, Taiwan, are selected as the study sites. The multispectral sensors, carried on an unmanned aerial vehicle (UAV), are adopted to acquire remote sensing data regarding water quality parameters, including chlorophyll-a (Chl-a), Secchi disk depth (SDD), and turbidity in the reservoirs. The experimental results indicate that, while MPP can reduce the influence of specular reflection on regression model establishment, specular reflection does hamper the correction of thematic map production. Due to water fluidity, sampling in situ should be followed by UAV imaging as soon as possible. Excluding turbidity, the obtained estimation accuracy can satisfy the national standard.
Ontology Matching Across Domains
2010-05-01
matching include GMO [1], Anchor-Prompt [2], and Similarity Flooding [3]. GMO is an iterative structural matcher, which uses RDF bipartite graphs to...AFRL under contract# FA8750-09-C-0058. References [1] Hu, W., Jian, N., Qu, Y., Wang, Y., “ GMO : a graph matching for ontologies”, in: Proceedings of
Energy Technology Data Exchange (ETDEWEB)
Theiler, James P [Los Alamos National Laboratory
2009-01-01
Following an analogous distinction in statistical hypothesis testing, we investigate variants of machine learning where the training set comes in matched pairs. We demonstrate that even conventional classifiers can exhibit improved performance when the input data has a matched-pair structure. Online algorithms, in particular, converge quicker when the data is presented in pairs. In some scenarios (such as the weak signal detection problem), matched pairs can be generated from independent samples, with the effect not only doubling the nominal size of the training set, but of providing the structure that leads to better learning. A family of 'dipole' algorithms is introduced that explicitly takes advantage of matched-pair structure in the input data and leads to further performance gains. Finally, we illustrate the application of matched-pair learning to chemical plume detection in hyperspectral imagery.
Electrodynamics analysis on coherent perfect absorber and phase-controlled optical switch.
Chen, Tianjie; Duan, Shaoguang; Chen, Y C
2012-05-01
A coherent perfect absorber is essentially a specially designed Fabry-Perot interferometer, which completely extinguishes the incident coherent light. The one- and two-beam coherent perfect absorbers have been analyzed using classical electrodynamics by considering index matching in layered structures to totally suppress reflections. This approach presents a clear and physically intuitive picture for the principle of operation of a perfect absorber. The results show that the incident beam(s) must have correct phases and amplitudes, and the real and imaginary parts of the refractive indices of the media in the interferometer must satisfy a well-defined relation. Our results are in agreement with those obtained using the S-matrix analysis. However, the results were obtained solely based on the superposition of waves from multiple reflections without invoking the concept of time reversal as does the S-matrix approach. Further analysis shows that the two-beam device can be configured to function as a phase-controlled three-state switch. © 2012 Optical Society of America
Jain, Anil K; Feng, Jianjiang
2011-01-01
Latent fingerprint identification is of critical importance to law enforcement agencies in identifying suspects: Latent fingerprints are inadvertent impressions left by fingers on surfaces of objects. While tremendous progress has been made in plain and rolled fingerprint matching, latent fingerprint matching continues to be a difficult problem. Poor quality of ridge impressions, small finger area, and large nonlinear distortion are the main difficulties in latent fingerprint matching compared to plain or rolled fingerprint matching. We propose a system for matching latent fingerprints found at crime scenes to rolled fingerprints enrolled in law enforcement databases. In addition to minutiae, we also use extended features, including singularity, ridge quality map, ridge flow map, ridge wavelength map, and skeleton. We tested our system by matching 258 latents in the NIST SD27 database against a background database of 29,257 rolled fingerprints obtained by combining the NIST SD4, SD14, and SD27 databases. The minutiae-based baseline rank-1 identification rate of 34.9 percent was improved to 74 percent when extended features were used. In order to evaluate the relative importance of each extended feature, these features were incrementally used in the order of their cost in marking by latent experts. The experimental results indicate that singularity, ridge quality map, and ridge flow map are the most effective features in improving the matching accuracy.
Mohr Gregoriussen, Angelica Maria; Bohr, Henrik Georg
2017-01-01
Donor-specific blood transfusion (DST) can lead to significant prolongation of allograft survival in experimental animal models and sometimes human recipients of solid organs. The mechanisms responsible for the beneficial effect on graft survival have been a topic of research and debate for decades and are not yet fully elucidated. Once we discover how the details of the mechanisms involved are linked, we could be within reach of a procedure making it possible to establish donor-specific tolerance with minimal or no immunosuppressive medication. Today, it is well established that CD4+Foxp3+ regulatory T cells (Tregs) are indispensable for maintaining immunological self-tolerance. A large number of animal studies have also shown that Tregs are essential for establishing and maintaining transplantation tolerance. In this paper, we present a hypothesis of one H2-haplotype-matched DST-induced transplantation tolerance (in mice). The formulated hypothesis is based on a re-interpretation of data from an immunogenetic experiment published by Niimi and colleagues in 2000. It is of importance that the naïve recipient mice in this study were never immunosuppressed and were therefore fully immune competent during the course of tolerance induction. Based on the immunological status of the recipients, we suggest that one H2-haplotype-matched self-specific Tregs derived from the transfusion blood can be activated and multiply in the host by binding to antigen-presenting cells presenting allopeptides in their major histocompatibility complex (MHC) class II (MHC-II). We also suggest that the endothelial and epithelial cells within the solid organ allograft upregulate the expression of MHC-II and attract the expanded Treg population to suppress inflammation within the graft. We further suggest that this biological process, here termed MHC-II recruitment, is a vital survival mechanism for organs (or the organism in general) when attacked by an immune system.
Scheme for achieving coherent perfect absorption by anisotropic metamaterials
Zhang, Xiujuan
2017-02-22
We propose a unified scheme to achieve coherent perfect absorption of electromagnetic waves by anisotropic metamaterials. The scheme describes the condition on perfect absorption and offers an inverse design route based on effective medium theory in conjunction with retrieval method to determine practical metamaterial absorbers. The scheme is scalable to frequencies and applicable to various incident angles. Numerical simulations show that perfect absorption is achieved in the designed absorbers over a wide range of incident angles, verifying the scheme. By integrating these absorbers, we further propose an absorber to absorb energy from two coherent point sources.
Towards optimal packed string matching
DEFF Research Database (Denmark)
Ben-Kiki, Oren; Bille, Philip; Breslauer, Dany
2014-01-01
In the packed string matching problem, it is assumed that each machine word can accommodate up to α characters, thus an n-character string occupies n/α memory words.(a) We extend the Crochemore–Perrin constant-space O(n)-time string-matching algorithm to run in optimal O(n/α) time and even in real......-time, achieving a factor α speedup over traditional algorithms that examine each character individually. Our macro-level algorithm only uses the standard AC0 instructions of the word-RAM model (i.e. no integer multiplication) plus two specialized micro-level AC0 word-size packed-string instructions. The main word...... matching work.(b) We also consider the complexity of the packed string matching problem in the classical word-RAM model in the absence of the specialized micro-level instructions wssm and wslm. We propose micro-level algorithms for the theoretically efficient emulation using parallel algorithms techniques...
Infographic explaining NCI-COG Pediatric MATCH, a cancer treatment clinical trial for children and adolescents, from 1 to 21 years of age, that is testing the use of precision medicine for pediatric cancers.
Perfect spin filtering by symmetry in molecular junctions
Li, Dongzhe; Dappe, Yannick J.; Smogunov, Alexander
2016-05-01
Obtaining highly spin-polarized currents in molecular junctions is crucial and important for nanoscale spintronics devices. Motivated by our recent symmetry-based theoretical argument for complete blocking of one spin conductance channel in model molecular junctions [A. Smogunov and Y. J. Dappe, Nano Lett. 15, 3552 (2015), 10.1021/acs.nanolett.5b01004], we explore the generality of the proposed mechanism and the degree of achieved spin-polarized current for realistic molecular junctions made of various ferromagnetic electrodes (Ni, Co, Fe) connected by different molecules (quaterthiophene or p -quaterphenyl). A simple analysis of the spin-resolved local density of states of a free electrode allowed us to identify the Fe(110) as the most optimal electrode, providing perfect spin filtering and high conductance at the same time. These results are confirmed by ab initio quantum transport calculations and are similar to those reported previously for model junctions. It is found, moreover, that the distortion of the p -quaterphenyl molecule plays an important role, reducing significantly the overall conductance.
PUMA: The Positional Update and Matching Algorithm
Line, J. L. B.; Webster, R. L.; Pindor, B.; Mitchell, D. A.; Trott, C. M.
2017-01-01
We present new software to cross-match low-frequency radio catalogues: the Positional Update and Matching Algorithm. The Positional Update and Matching Algorithm combines a positional Bayesian probabilistic approach with spectral matching criteria, allowing for confusing sources in the matching process. We go on to create a radio sky model using Positional Update and Matching Algorithm based on the Murchison Widefield Array Commissioning Survey, and are able to automatically cross-match 98.5% of sources. Using the characteristics of this sky model, we create simple simulated mock catalogues on which to test the Positional Update and Matching Algorithm, and find that Positional Update and Matching Algorithm can reliably find the correct spectral indices of sources, along with being able to recover ionospheric offsets. Finally, we use this sky model to calibrate and remove foreground sources from simulated interferometric data, generated using OSKAR (the Oxford University visibility generator). We demonstrate that there is a substantial improvement in foreground source removal when using higher frequency and higher resolution source positions, even when correcting positions by an average of 0.3 arcmin given a synthesised beam-width of 2.3 arcmin.
On stagnation pressure increases in calorically perfect, ideal gases
International Nuclear Information System (INIS)
Williams, D.M.; Kamenetskiy, D.S.; Spalart, P.R.
2016-01-01
Highlights: • Unaveraged transport equation is obtained for the stagnation pressure. • Reynolds-averaged transport equation is obtained for the stagnation pressure. • Transport equations apply to compressible flow of calorically perfect, ideal gas. • Stagnation pressure is shown to be capable of naturally or artificially increasing. • Spurious overshoots likely in shear layers displaying convex streamline curvature. - Abstract: When stagnation pressure rises in a natural or numerically simulated flow it is frequently a cause for concern, as one usually expects viscosity and turbulence to cause stagnation pressure to decrease. In fact, if stagnation pressure increases, one may suspect measurement or numerical errors. However, this need not be the case, as the laws of nature do not require that stagnation pressure continually decreases. In order to help clarify matters, the objective of this work is to understand the conditions under which stagnation pressure will rise in the unsteady/steady flows of compressible, viscous, calorically perfect, ideal gases. Furthermore, at a more practical level, the goal is to understand the conditions under which stagnation pressure will increase in flows simulated with the Reynolds averaged Navier–Stokes equations and eddy-viscosity turbulence models. In order to provide an improved understanding of increases in stagnation pressure for both these scenarios, transport equations are derived that govern its behavior in the unaveraged and Reynolds averaged settings. These equations are utilized to precisely determine the relationship between changes in stagnation pressure and zeroth, first, and second derivatives of fundamental flow quantities. Furthermore, these equations are utilized to demonstrate the relationship between changes in stagnation pressure and fundamental non-dimensional quantities that govern the conductivity, viscosity, and compressibility of the flow. In addition, based on an analysis of the Reynolds
Perfection and the Bomb: Nuclear Weapons, Teleology, and Motives.
Brummett, Barry
1989-01-01
Uses Kenneth Burke's theory of perfection to explore the vocabularies of nuclear weapons in United States public discourse and how "the Bomb" as a God term has gained imbalanced ascendancy in centers of power. (MS)
Perfect imaging with positive refraction in three dimensions
International Nuclear Information System (INIS)
Leonhardt, Ulf; Philbin, Thomas G.
2010-01-01
Maxwell's fish eye has been known to be a perfect lens within the validity range of ray optics since 1854. Solving Maxwell's equations, we show that the fish-eye lens in three dimensions has unlimited resolution for electromagnetic waves.
Mastering surgical skills through simulation-based learning: Practice makes one perfect
Directory of Open Access Journals (Sweden)
Niti Khunger
2016-01-01
Full Text Available Simulation-based learning in surgery is a learning model where an environment similar to real life surgical situation is created for the trainee to learn various surgical skills. It can be used to train a new operator as well to assess his skills. This methodology helps in repetitive practice of surgical skills on nonliving things so that the operator can be near-perfect when operating on a live patient. Various models are available for learning different dermatosurgery skills.
Mastering Surgical Skills Through Simulation-Based Learning: Practice Makes One Perfect.
Khunger, Niti; Kathuria, Sushruta
2016-01-01
Simulation-based learning in surgery is a learning model where an environment similar to real life surgical situation is created for the trainee to learn various surgical skills. It can be used to train a new operator as well to assess his skills. This methodology helps in repetitive practice of surgical skills on nonliving things so that the operator can be near-perfect when operating on a live patient. Various models are available for learning different dermatosurgery skills.
Perfect state transfer without state initialization and remote collaboration
International Nuclear Information System (INIS)
Markiewicz, Marcin; Wiesniak, Marcin
2009-01-01
We present a perfect state transfer protocol via a qubit chain with the evolution governed by the xx Hamiltonian. In contrast to the recent protocol announced in Phys. Rev. Lett. 101, 230502 (2008), our method does not demand any remote-cooperated initialization and sending classical information about measurement outcomes. We achieve the perfect state transfer only with the assumption of access to two spins at each end of the chain, while the initial state of the whole chain is irrelevant.
Zeroth Poisson Homology, Foliated Cohomology and Perfect Poisson Manifolds
Martínez-Torres, David; Miranda, Eva
2018-01-01
We prove that, for compact regular Poisson manifolds, the zeroth homology group is isomorphic to the top foliated cohomology group, and we give some applications. In particular, we show that, for regular unimodular Poisson manifolds, top Poisson and foliated cohomology groups are isomorphic. Inspired by the symplectic setting, we define what a perfect Poisson manifold is. We use these Poisson homology computations to provide families of perfect Poisson manifolds.
Perfect 2-colorings of the generalized Petersen graph
Indian Academy of Sciences (India)
There are no perfect 2-colorings of GP(n, 2) with the matrix A3. Proof. Suppose, contrary to our claim, there is a perfect 2-coloring of GP(n, 2) with the matrix A3. By Lemma 3.4, there are 2 vertices ai and bi, for some 0 ≤ i ≤ n−1, such that they are the same color. By symmetry, without loss of generality, we can assume T (a0) ...
A blind matching algorithm for cognitive radio networks
Hamza, Doha R.
2016-08-15
We consider a cognitive radio network where secondary users (SUs) are allowed access time to the spectrum belonging to the primary users (PUs) provided that they relay primary messages. PUs and SUs negotiate over allocations of the secondary power that will be used to relay PU data. We formulate the problem as a generalized assignment market to find an epsilon pairwise stable matching. We propose a distributed blind matching algorithm (BLMA) to produce the pairwise-stable matching plus the associated power allocations. We stipulate a limited information exchange in the network so that agents only calculate their own utilities but no information is available about the utilities of any other users in the network. We establish convergence to epsilon pairwise stable matchings in finite time. Finally we show that our algorithm exhibits a limited degradation in PU utility when compared with the Pareto optimal results attained using perfect information assumptions. © 2016 IEEE.
University Reactor Matching Grants Program
International Nuclear Information System (INIS)
John Valentine; Farzad Rahnema; Said Abdel-Khalik
2003-01-01
During the 2002 Fiscal year, funds from the DOE matching grant program, along with matching funds from the industrial sponsors, have been used to support research in the area of thermal-hydraulics. Both experimental and numerical research projects have been performed. Experimental research focused on two areas: (1) Identification of the root cause mechanism for axial offset anomaly in pressurized water reactors under prototypical reactor conditions, and (2) Fluid dynamic aspects of thin liquid film protection schemes for inertial fusion reactor chambers. Numerical research focused on two areas: (1) Multi-fluid modeling of both two-phase and two-component flows for steam conditioning and mist cooling applications, and (2) Modeling of bounded Rayleigh-Taylor instability with interfacial mass transfer and fluid injection through a porous wall simulating the ''wetted wall'' protection scheme in inertial fusion reactor chambers. Details of activities in these areas are given
Marques, Luís.; Roca Cladera, Josep; Tenedório, José António
2017-10-01
The use of multiple sets of images with high level of overlapping to extract 3D point clouds has increased progressively in recent years. There are two main fundamental factors in the origin of this progress. In first, the image matching algorithms has been optimised and the software available that supports the progress of these techniques has been constantly developed. In second, because of the emergent paradigm of smart cities which has been promoting the virtualization of urban spaces and their elements. The creation of 3D models for urban elements is extremely relevant for urbanists to constitute digital archives of urban elements and being especially useful for enrich maps and databases or reconstruct and analyse objects/areas through time, building and recreating scenarios and implementing intuitive methods of interaction. These characteristics assist, for example, higher public participation creating a completely collaborative solution system, envisioning processes, simulations and results. This paper is organized in two main topics. The first deals with technical data modelling obtained by terrestrial photographs: planning criteria for obtaining photographs, approving or rejecting photos based on their quality, editing photos, creating masks, aligning photos, generating tie points, extracting point clouds, generating meshes, building textures and exporting results. The application of these procedures results in 3D models for the visualization of urban elements of the city of Barcelona. The second concerns the use of Augmented Reality through mobile platforms allowing to understand the city origins and the relation with the actual city morphology, (en)visioning solutions, processes and simulations, making possible for the agents in several domains, to fundament their decisions (and understand them) achieving a faster and wider consensus.
Equilibrium and matching under price controls
Herings, P.J.J.
2015-01-01
The paper considers a one-to-one matching with contracts model in the presence of price controls. This set-up contains two important streams in the matching literature, those with and those without monetary transfers, as special cases and allows for intermediate cases with some restrictions on the
Whole genome association mapping by incompatibilities and local perfect phylogenies
Directory of Open Access Journals (Sweden)
Besenbacher Søren
2006-10-01
Full Text Available Abstract Background With current technology, vast amounts of data can be cheaply and efficiently produced in association studies, and to prevent data analysis to become the bottleneck of studies, fast and efficient analysis methods that scale to such data set sizes must be developed. Results We present a fast method for accurate localisation of disease causing variants in high density case-control association mapping experiments with large numbers of cases and controls. The method searches for significant clustering of case chromosomes in the "perfect" phylogenetic tree defined by the largest region around each marker that is compatible with a single phylogenetic tree. This perfect phylogenetic tree is treated as a decision tree for determining disease status, and scored by its accuracy as a decision tree. The rationale for this is that the perfect phylogeny near a disease affecting mutation should provide more information about the affected/unaffected classification than random trees. If regions of compatibility contain few markers, due to e.g. large marker spacing, the algorithm can allow the inclusion of incompatibility markers in order to enlarge the regions prior to estimating their phylogeny. Haplotype data and phased genotype data can be analysed. The power and efficiency of the method is investigated on 1 simulated genotype data under different models of disease determination 2 artificial data sets created from the HapMap ressource, and 3 data sets used for testing of other methods in order to compare with these. Our method has the same accuracy as single marker association (SMA in the simplest case of a single disease causing mutation and a constant recombination rate. However, when it comes to more complex scenarios of mutation heterogeneity and more complex haplotype structure such as found in the HapMap data our method outperforms SMA as well as other fast, data mining approaches such as HapMiner and Haplotype Pattern Mining (HPM
THE PERFECT ONLINE COURSE: Best Practices for Designing and Teaching
Directory of Open Access Journals (Sweden)
Reviewed by Cengiz Hakan AYDIN
2010-07-01
Full Text Available The growth of online learning all over the world arise new challenges. One of the major challenges is the issue of quality. What should an online course look like? What kinds of instructional strategies should be provided? To what extent various kinds of interactions must be required? What are the effective learning activities? For what functions should different technologies be used? How can learning be assessed? And similar and more questions have yet no standardized answers although they have been around since early implementations of online learning. Each provider uses different standards developed by either themselves or some institutions or some researchers. Sloan-C: Pillars of Quality, Robley and Wince’s Rubric for Quality Interactions, Concord Model, Schrum’s Qualities of Successful Students, Quality Matters, and E-excellence: Quality Manual for E-learning in Higher Education are among many of these standards.The book, entitled as The Perfect Online Course: Best Practices for Designing and Teaching is also trying to establish a list of standards about how to design and implement an effective online course.The main goal of the book is to create a framework of quality educational guidelines that can be used to offer “perfect” online course.
Shear-free perfect fluids with zero magnetic Weyl tensor
International Nuclear Information System (INIS)
Collins, C.B.
1984-01-01
Rotating, shear-free general-relativistic perfect fluids are investigated. It is first shown that, if the fluid pressure, p, and energy density, μ, are related by a barotropic equation of state p = p( μ) satifying μ+pnot =0, and if the magnetic part of the Weyl tensor (with respect to the fluid flow) vanishes, then the fluid's volume expansion is zero. The class of all such fluids is subsequently characterized. Further analysis of the solutions shows that, in general, the space-times may be regarded as being locally stationary and axisymmetric (they admit a two-dimensional Abelian isometry group with timelike orbits, which is in fact orthogonally transistive), although various specializations can occur, with the ''most special'' case being the well-known Goedel model, which is space-time homogeneous (it admits a five-dimensional isometry group acting multiply transitively on the space-time). all solutions are of Petrov type D. The fact that there are any solutions in the class at all means that a theorem appearing in the literature is invalid, and the existence of some special solutions in which the fluid's vorticity vector is orthogonal to the acceleration reveals the incompleteness of a previous study of a class of space-times, in which there are Killing vectors parallel to the fluid four-velocity and to the vorticity vector
Building the perfect parasite: cell division in apicomplexa.
Directory of Open Access Journals (Sweden)
Boris Striepen
2007-06-01
Full Text Available Apicomplexans are pathogens responsible for malaria, toxoplasmosis, and crytposporidiosis in humans, and a wide range of livestock diseases. These unicellular eukaryotes are stealthy invaders, sheltering from the immune response in the cells of their hosts, while at the same time tapping into these cells as source of nutrients. The complexity and beauty of the structures formed during their intracellular development have made apicomplexans the darling of electron microscopists. Dramatic technological progress over the last decade has transformed apicomplexans into respectable genetic model organisms. Extensive genomic resources are now available for many apicomplexan species. At the same time, parasite transfection has enabled researchers to test the function of specific genes through reverse and forward genetic approaches with increasing sophistication. Transfection also introduced the use of fluorescent reporters, opening the field to dynamic real time microscopic observation. Parasite cell biologists have used these tools to take a fresh look at a classic problem: how do apicomplexans build the perfect invasion machine, the zoite, and how is this process fine-tuned to fit the specific niche of each pathogen in this ancient and very diverse group? This work has unearthed a treasure trove of novel structures and mechanisms that are the focus of this review.
Ganiou, M. G.; Houndjo, M. J. S.; Salako, Ines G.; Rodrigues, M. E.; Tossa, J.
2016-07-01
We describe in this paper the observables of inflationary models, in particular the spectrum index of torsion scalar perturbations, the tensor-to-scalar ratio, and the running of the spectral index, in the framework of perfect fluid models and F(T) gravity theories through the reconstruction methods. Then, our results on the perfect fluid and F(T) gravity theories of inflation are compared with recent cosmological observations such as the Planck satellite and BICEP2 experiment. Our studies prove that the perfect fluid and F(T) gravity models can reproduce the inflationary Universe consistent above all with the Planck data. We have reconstructed several models and considered others which give the best fit values compatible with the spectral index of curvature perturbations, the tensor-to-scalar ratio, and the running of the spectral index within the allowed ranges suggested by the Planck and BICEP2 results. By taking the trace-anomaly into consideration, we have shown that the reconstructed models F(T) can not describe a finite de Sitter inflation without an additional constant n that we related to cosmological constant.
Bellahsene, Zohra; Rahm, Erhard
2011-01-01
Requiring heterogeneous information systems to cooperate and communicate has now become crucial, especially in application areas like e-business, Web-based mash-ups and the life sciences. Such cooperating systems have to automatically and efficiently match, exchange, transform and integrate large data sets from different sources and of different structure in order to enable seamless data exchange and transformation. The book edited by Bellahsene, Bonifati and Rahm provides an overview of the ways in which the schema and ontology matching and mapping tools have addressed the above requirements
A perfect storm? Welfare, care, gender and generations in Uruguay.
Filgueira, Fernando; Gutiérrez, Magdalena; Papadópulos, Jorge
2011-01-01
This article claims that welfare states modelled on a contributory basis and with a system of entitlements that assumes stable two-parent families, a traditional breadwinner model, full formal employment and a relatively young age structure are profoundly flawed in the context of present-day challenges. While this is true for affluent countries modelled on the Bismarckian type of welfare system, the costs of the status quo are even more devastating in middle-income economies with high levels of inequality. A gendered approach to welfare reform that introduces the political economy and the economy of care and unpaid work is becoming critical to confront what may very well become a perfect storm for the welfare of these nations and their peoples. Through an in-depth study of the Uruguayan case, the authors show how the decoupling of risk and protection has torn asunder the efficacy of welfare devices in the country. An ageing society that has seen a radical transformation of its family and labour market landscapes, Uruguay maintained during the 1980s and 1990s a welfare state that was essentially contributory, elderly and male-oriented, and centred on cash entitlements. This contributed to the infantilization of poverty, increased the vulnerability of women and exacerbated fiscal stress for the system as a whole. Furthermore, because of high levels of income and asset inequality, the redistribution of risk between upper- and lower-income groups presented a deeply regressive pattern. The political economy of care and welfare has begun to change in the last decade or so, bringing about mild reforms in the right direction; but these might prove to be too little and too late.
[Integral parameters of electrocardiogram: perfection of assessment].
Volobuev, A N; Kondurtsev, V A; Romanchuk, P I; Bazarova, V N
2001-01-01
The role of such parameter as electric quality of the heart (EQH) is assessed by a biophysical analysis of a new model of dipolic equivalent electric generator of the heart taking account of myocardial inductivity in the course of excitation. How to estimate EQH by standard ECG parameters using calculated nomogram is shown. Results of EQH estimation in the course of treatment are provided.
A symbolic shortest path algorithm for computing subgame-perfect Nash equilibria
Directory of Open Access Journals (Sweden)
Góngora Pedro A.
2015-09-01
Full Text Available Consider games where players wish to minimize the cost to reach some state. A subgame-perfect Nash equilibrium can be regarded as a collection of optimal paths on such games. Similarly, the well-known state-labeling algorithm used in model checking can be viewed as computing optimal paths on a Kripke structure, where each path has a minimum number of transitions. We exploit these similarities in a common generalization of extensive games and Kripke structures that we name “graph games”. By extending the Bellman-Ford algorithm for computing shortest paths, we obtain a model-checking algorithm for graph games with respect to formulas in an appropriate logic. Hence, when given a certain formula, our model-checking algorithm computes the subgame-perfect Nash equilibrium (as opposed to simply determining whether or not a given collection of paths is a Nash equilibrium. Next, we develop a symbolic version of our model checker allowing us to handle larger graph games. We illustrate our formalism on the critical-path method as well as games with perfect information. Finally, we report on the execution time of benchmarks of an implementation of our algorithms
Characteristic Evolution and Matching
Directory of Open Access Journals (Sweden)
Winicour Jeffrey
2001-01-01
Full Text Available I review the development of numerical evolution codes for general relativity based upon the characteristic initial value problem. Progress is traced from the early stage of 1D feasibility studies to current 3D codes that simulate binary black holes. A prime application of characteristic evolution is Cauchy-characteristic matching, which is also reviewed.
Characteristic Evolution and Matching
Directory of Open Access Journals (Sweden)
Winicour Jeffrey
1998-05-01
Full Text Available We review the development of numerical evolution codes for general relativity based upon the characteristic initial value problem. Progress is traced from the early stage of 1D feasibility studies to current 3D black hole codes that run forever. A prime application of characteristic evolution is Cauchy-characteristic matching, which is also reviewed.
Zhou, Feng; de la Torre, Fernando
2015-11-19
Graph matching (GM) is a fundamental problem in computer science, and it plays a central role to solve correspondence problems in computer vision. GM problems that incorporate pairwise constraints can be formulated as a quadratic assignment problem (QAP). Although widely used, solving the correspondence problem through GM has two main limitations: (1) the QAP is NP-hard and difficult to approximate; (2) GM algorithms do not incorporate geometric constraints between nodes that are natural in computer vision problems. To address aforementioned problems, this paper proposes factorized graph matching (FGM). FGM factorizes the large pairwise affinity matrix into smaller matrices that encode the local structure of each graph and the pairwise affinity between edges. Four are the benefits that follow from this factorization: (1) There is no need to compute the costly (in space and time) pairwise affinity matrix; (2) The factorization allows the use of a path-following optimization algorithm, that leads to improved optimization strategies and matching performance; (3) Given the factorization, it becomes straight-forward to incorporate geometric transformations (rigid and non-rigid) to the GM problem. (4) Using a matrix formulation for the GM problem and the factorization, it is easy to reveal commonalities and differences between different GM methods. The factorization also provides a clean connection with other matching algorithms such as iterative closest point; Experimental results on synthetic and real databases illustrate how FGM outperforms state-of-the-art algorithms for GM. The code is available at http://humansensing.cs.cmu.edu/fgm.
Forbidden Structures for Planar Perfect Consecutively Colourable Graphs
Directory of Open Access Journals (Sweden)
Borowiecka-Olszewska Marta
2017-05-01
Full Text Available A consecutive colouring of a graph is a proper edge colouring with posi- tive integers in which the colours of edges incident with each vertex form an interval of integers. The idea of this colouring was introduced in 1987 by Asratian and Kamalian under the name of interval colouring. Sevast- janov showed that the corresponding decision problem is NP-complete even restricted to the class of bipartite graphs. We focus our attention on the class of consecutively colourable graphs whose all induced subgraphs are consecutively colourable, too. We call elements of this class perfect consecutively colourable to emphasise the conceptual similarity to perfect graphs. Obviously, the class of perfect consecutively colourable graphs is induced hereditary, so it can be characterized by the family of induced forbidden graphs. In this work we give a necessary and sufficient conditions that must be satisfied by the generalized Sevastjanov rosette to be an induced forbid- den graph for the class of perfect consecutively colourable graphs. Along the way, we show the exact values of the deficiency of all generalized Sevastjanov rosettes, which improves the earlier known estimating result. It should be mentioned that the deficiency of a graph measures its closeness to the class of consecutively colourable graphs. We motivate the investigation of graphs considered here by showing their connection to the class of planar perfect consecutively colourable graphs.
L2 acquisition of English present perfect interpretations
Directory of Open Access Journals (Sweden)
Sviatlana Karpava
2013-06-01
Full Text Available The present study investigates the role of first language (L1, in our case Cypriot Greek (CG or Standard Greek (SG, in the second language (L2 acquisition of English present perfect in terms of form and meaning possibilities. With respect to native speakers of CG in particular, the primary goal is to determine whether transfer from the mother-tongue, in which present perfect has only a resultative reading and simple past a resultative, an existential or a definite reading, influences the acquisition of the English present perfect. It is assumed that L2 acquisition involves establishing connections between the semantic properties/overt markers for each reading and the English present perfect. Diagnostic tests proposed by Agouraki (2006 are employed in this study, based on the (incompatibility of certain types of adverbial markers with the existential reading and the resultative reading, respectively, as well as on the distinct semantic properties of the two readings. Almost 400 participants took part in this research. The results show that there is a certain effect of L1 on the L2 acquisition of English present perfect by CG- and SG-speaking pupils, which is argued to be mainly due to the different patterns of meanings and forms in CG, SG and English.
Whole or incomplete: the myth of body perfection
Directory of Open Access Journals (Sweden)
Abha Khetarpal
2017-08-01
Full Text Available The media’s and society’s prejudice in favor of ‘ablesim’ propagates the myth of body perfection. As a result we pursue perfection – the concept of ableism invades our minds as well as our culture and we all succumb to it’s lure. Disability is socially constructed; it is ableism that compels people to believe that perfection is normal. This belief is nothing less than social oppression. Even the rehabilitation therapies send out strong signals that persons with disabilities are ‘deficient’ and ‘abnormal’, and that to become a "valued" person they would have to overcome their disabilities. Since the physical component of self-concept is important in maintenance of health and in identity formation, such pressures can lead to a distortion of self-concept. The desire for human perfection can lead to medical conditions such as obsessive compulsive disorder, anorexia nervosa, or depression. It can also impact our understanding of what it means to be human and what signifies a perfect or happy life. This article expounds on why we must achieve, value, and polish psychological maturity through awareness, self-regulation, and honesty.
Matching Supernovae to Galaxies
Kohler, Susanna
2016-12-01
developed a new automated algorithm for matching supernovae to their host galaxies. Their work builds on currently existing algorithms and makes use of information about the nearby galaxies, accounts for the uncertainty of the match, and even includes a machine learning component to improve the matching accuracy.Gupta and collaborators test their matching algorithm on catalogs of galaxies and simulated supernova events to quantify how well the algorithm is able to accurately recover the true hosts.Successful MatchingThe matching algorithms accuracy (purity) as a function of the true supernova-host separation, the supernova redshift, the true hosts brightness, and the true hosts size. [Gupta et al. 2016]The authors find that when the basic algorithm is run on catalog data, it matches supernovae to their hosts with 91% accuracy. Including the machine learning component, which is run after the initial matching algorithm, improves the accuracy of the matching to 97%.The encouraging results of this work which was intended as a proof of concept suggest that methods similar to this could prove very practical for tackling future survey data. And the method explored here has use beyond matching just supernovae to their host galaxies: it could also be applied to other extragalactic transients, such as gamma-ray bursts, tidal disruption events, or electromagnetic counterparts to gravitational-wave detections.CitationRavi R. Gupta et al 2016 AJ 152 154. doi:10.3847/0004-6256/152/6/154
Self-similar spatially homogeneous cosmologies: orthogonal perfect fluid and vacuum solutions
International Nuclear Information System (INIS)
Hsu, L.; Wainwright, J.
1986-01-01
It is known that the asymptotic states of a large class of spatially homogeneous cosmological models, near the big bang and at late times, are described by exact self-similar solutions. With this as motivation, all spatially homogeneous solutions of the Einstein field equations are found, which have an orthogonal perfect fluid as source, or are vacuum, and admit a similarity group H 4 which acts transitively on spacetime. (author)
Programmatic material on perfection of competition activity of highly skilled basketball players.
Directory of Open Access Journals (Sweden)
Sushko Ruslana Aleksandrovna
2011-09-01
Full Text Available The special facilities are considered for creation of the programs of correction of training process and perfection of competitiveness activity. Basic estimations and structure of correction of technical tactical actions are resulted. It is set that programmatic material must take into account playing specialization of basketball-player, model indexes. It is also necessary to take into account optimization and modification of existent technologies of estimation of technical tactical actions.
[Propensity score matching in SPSS].
Huang, Fuqiang; DU, Chunlin; Sun, Menghui; Ning, Bing; Luo, Ying; An, Shengli
2015-11-01
To realize propensity score matching in PS Matching module of SPSS and interpret the analysis results. The R software and plug-in that could link with the corresponding versions of SPSS and propensity score matching package were installed. A PS matching module was added in the SPSS interface, and its use was demonstrated with test data. Score estimation and nearest neighbor matching was achieved with the PS matching module, and the results of qualitative and quantitative statistical description and evaluation were presented in the form of a graph matching. Propensity score matching can be accomplished conveniently using SPSS software.
INFORMATION SYSTEMS AUDIT CURRICULA CONTENT MATCHING
Vasile-Daniel CARDOȘ; Ildikó Réka CARDOȘ
2014-01-01
Financial and internal auditors must cope with the challenge of performing their mission in technology enhanced environment. In this article we match the information technology description found in the International Federation of Accountants (IFAC) and the Institute of Internal Auditors (IIA) curricula against the Model Curriculum issued by the Information Systems Audit and Control Association (ISACA). By reviewing these three curricula, we matched the content in the ISACA Model Curriculum wi...
Directory of Open Access Journals (Sweden)
Tao Wu
2017-03-01
Full Text Available Positive obstacles will cause damage to field robotics during traveling in field. Field autonomous land vehicle is a typical field robotic. This article presents a feature matching and fusion-based algorithm to detect obstacles using LiDARs for field autonomous land vehicles. There are three main contributions: (1 A novel setup method of compact LiDAR is introduced. This method improved the LiDAR data density and reduced the blind region of the LiDAR sensor. (2 A mathematical model is deduced under this new setup method. The ideal scan line is generated by using the deduced mathematical model. (3 Based on the proposed mathematical model, a feature matching and fusion (FMAF-based algorithm is presented in this article, which is employed to detect obstacles. Experimental results show that the performance of the proposed algorithm is robust and stable, and the computing time is reduced by an order of two magnitudes by comparing with other exited algorithms. This algorithm has been perfectly applied to our autonomous land vehicle, which has won the champion in the challenge of Chinese “Overcome Danger 2014” ground unmanned vehicle.
M-band nonlinear subband decompositions with perfect reconstruction.
Hampson, F J; Pesquet, J C
1998-01-01
We investigate nonlinear multirate filterbanks with maximal decimation and perfect reconstruction. Definitions of the desired properties of such structures are given for general nonlinear filterbanks. We then consider a triangular representation of linear filterbanks and see that it may be easily extended to the nonlinear case. Furthermore, general nonlinear filterbanks are presented, for which perfect reconstruction is either inherently guaranteed or ensured subject to an easily verified condition. Extensions to bidimensional filters are also discussed and an application for nonlinear multiresolution schemes to feature sieves is shown.
Dual band metamaterial perfect absorber based on Mie resonances
Energy Technology Data Exchange (ETDEWEB)
Liu, Xiaoming; Lan, Chuwen; Li, Bo; Zhou, Ji, E-mail: zhouji@tsinghua.edu.cn [State Key Laboratory of New Ceramics and Fine Processing, School of Materials Science and Engineering, Tsinghua University, Beijing 100084 (China); Bi, Ke [School of Science, Beijing University of Posts and Telecommunications, Beijing 100876 (China); Zhao, Qian [State Key Lab of Tribology, Department of Precision Instruments and Mechanology, Tsinghua University, Beijing 100084 (China)
2016-08-08
We numerically and experimentally demonstrated a polarization insensitive dual-band metamaterial perfect absorber working in wide incident angles based on the two magnetic Mie resonances of a single dielectric “atom” with simple structure. Two absorption bands with simulated absorptivity of 99% and 96%, experimental absorptivity of 97% and 94% at 8.45 and 11.97 GHz were achieved due to the simultaneous magnetic and electric resonances in dielectric “atom” and copper plate. Mie resonances of dielectric “atom” provide a simple way to design metamaterial perfect absorbers with high symmetry.
Hydrogen can be used as a perfect fuel
International Nuclear Information System (INIS)
Aydin, E.
2005-01-01
At present, hydrogen is one of the new and clean energy production sources. Hydrogen is the perfect partner for electricity, and together they create an integrated energy system based on distributed power generation and use. Hydrogen and electricity are interchangeable using a fuel cell (to convert hydrogen to electricity) or an electrolyzer (for converting electricity to hydrogen). A regenerative fuel cell works either way, converting hydrogen to electricity and vice versa. Hydrogen and electricity are both energy carriers because, unlike naturally occurring hydrocarbon fuels, they must both be produced using a primary energy source. In this study, it will be discussed whether hydrogen is perfect fuel or not
Perfect routing of quantum information in regular cavity QED networks
Behzadi, Naghi; Rudsary, Sobhan Kazemi; Salmasi, Bahram Ahansaz
2013-12-01
We introduce a scheme for perfect routing of quantum states and entanglement in regular cavity QED networks. The couplings between the cavities are quasi-uniform and each cavity is doped with a two-level atom. Quasi-uniform couplings leads the system to evolve in invariant subspaces. Combination the evolutions of the system in its invariant subspaces with quite simple local operations on atoms in the networks, gives the perfect routing of quantum states and entanglement through the network. To provide the protocol be robust due to decoherence arisen from photon loss, the field mode of the cavities are only virtually excited.
Exploiting Best-Match Equations for Efficient Reinforcement Learning
van Seijen, Harm; Whiteson, Shimon; van Hasselt, Hado; Wiering, Marco
This article presents and evaluates best-match learning, a new approach to reinforcement learning that trades off the sample efficiency of model-based methods with the space efficiency of model-free methods. Best-match learning works by approximating the solution to a set of best-match equations,
Electromagnetic wave matching device
International Nuclear Information System (INIS)
Hirata, Yosuke; Mitsunaka, Yoshika; Hayashi, Ken-ichi; Ito, Yasuyuki.
1997-01-01
The present invention provides a matching device capable of increasing an efficiency of combining beams of electromagnetic waves outputted from an output window of a gyrotron which is expected for plasma heating of a thermonuclear reactor and an electromagnetic wave transmission system as high as possible. Namely, an electromagnetic wave matching device reflects beams of electromagnetic waves incident from an inlet by a plurality of phase correction mirrors and combines them to an external transmission system through an exit. In this case, the phase correction mirrors change the phase of the beams of electromagnetic waves incident to the phase correction mirrors by a predetermined amount corresponding to the position of the reflection mirrors. Then, the beams of electromagnetic waves outputted, for example, from a gyrotron can properly be shaped as desired for the intensity and the phase. As a result, combination efficiency with the transmission system can be increased. (I.S.)
A Family of Bipartite |Cardinality Matching Problems Solvable in O(n\\^2) Time
DEFF Research Database (Denmark)
Clausen, Jens; Krarup, J.
1995-01-01
For a given, unweighted bipartite graph G with 2n non isolated vertices, we consider the so called bipartite cardinality matching problem (BCMP) for which the time complexity of the fastest exact algorithm available is O(n/sup 5/2/ ). We devise a greedy algorithm which either finds a perfect...... matching in O(n/sup 2/ ) time or identifies cycle of length 4 in the complement G of G...
Perfect absorption in 1D photonic crystal nanobeam embedded with graphene/Al2O3 multilayer stack
Liu, Hanqing; Zha, Song; Liu, Peiguo; Zhou, Xiaotian; Bian, Li-an
2018-05-01
We exploit the concept of critical coupling to graphene based chip-integrated applications and numerically demonstrate that a perfect absorption (PA) absorber in the near-infrared can be obtained by graphene/Al2O3 multilayer stack (GAMS) critical coupling with a resonant cavity in the 1D photonic crystal nanobeam (PCN). The key point is dynamically matching the coupling rate of incident light wave to the cavity with the absorbing rate of GAMS via electrically modulating the chemical potential of graphene. Simulation results show that the radius of GAMS as well as the thickness of Al2O3 layer are closely connected with the performance of perfect absorption. These results may provide potential applications in the high-density integrated optical devices, photolectric transducers, and laser pulse limiters.
Characteristic Evolution and Matching
Directory of Open Access Journals (Sweden)
Winicour Jeffrey
2005-12-01
Full Text Available I review the development of numerical evolution codes for general relativity based upon the characteristic initial value problem. Progress is traced from the early stage of 1D feasibility studies to 2D axisymmetric codes that accurately simulate the oscillations and gravitational collapse of relativistic stars and to current 3D codes that provide pieces of a binary black hole spacetime. A prime application of characteristic evolution is to compute waveforms via Cauchy-characteristic matching, which is also reviewed.
Directory of Open Access Journals (Sweden)
Clint Zeringue
2010-01-01
Full Text Available A technique to tune a magnetic quasi-phase matching in-fiber isolator through the application of stress induced by two mutually orthogonal capillary tubes filled with liquid ethanol is investigated numerically. The results show that it is possible to “tune” the birefringence in these fibers over a limited range depending on the temperature at which the ethanol is loaded into the capillaries. Over this tuning range, the thermal sensitivity of the birefringence is an order-of-magnitude lower than conventional fibers, making this technique well suited for magnetic quasi-phase matching.
International Nuclear Information System (INIS)
Longhi, Stefano
2014-01-01
Quantum recurrence and dynamic localization are investigated in a class of ac-driven tight-binding Hamiltonians, the Krawtchouk quantum chain, which in the undriven case provides a paradigmatic Hamiltonian model that realizes perfect quantum state transfer and mirror inversion. The equivalence between the ac-driven single-particle Krawtchouk Hamiltonian H -hat (t) and the non-interacting ac-driven bosonic junction Hamiltonian enables to determine in a closed form the quasi energy spectrum of H -hat (t) and the conditions for exact wave packet reconstruction (dynamic localization). In particular, we show that quantum recurrence, which is predicted by the general quantum recurrence theorem, is exact for the Krawtchouk quantum chain in a dense range of the driving amplitude. Exact quantum recurrence provides perfect wave packet reconstruction at a frequency which is fractional than the driving frequency, a phenomenon that can be referred to as fractional dynamic localization
Dudebout, Nicolas
2014-12-15
This paper proves that exogenous empirical-evidence equilibria (xEEEs) in perfect-monitoring repeated games induce correlated equilibria of the associated one-shot game. An empirical-evidence equilibrium (EEE) is a solution concept for stochastic games. At equilibrium, agents\\' strategies are optimal with respect to models of their opponents. These models satisfy a consistency condition with respect to the actual behavior of the opponents. As such, EEEs replace the full-rationality requirement of Nash equilibria by a consistency-based bounded-rationality one. In this paper, the framework of empirical evidence is summarized, with an emphasis on perfect-monitoring repeated games. A less constraining notion of consistency is introduced. The fact that an xEEE in a perfect-monitoring repeated game induces a correlated equilibrium on the underlying one-shot game is proven. This result and the new notion of consistency are illustrated on the hawk-dove game. Finally, a method to build specific correlated equilibria from xEEEs is derived.
Development of a perfect prognosis probabilistic model for ...
Indian Academy of Sciences (India)
of detection of 77% with a false alarm rate of 35%. The Brier Skill Score .... For identify- ing the cases, we have considered only the months. March–October with reasonable lightning activity. The 115 lightning cases identified are the cases in which the CG ..... quadratic function, the Cressman method is used for nudging ...
Zhang, Rufan; Zhang, Yingying; Wei, Fei
2017-02-21
breaking strain (>17.5%) reach the theoretical limits. They also show excellent electrical and thermal properties. In addition, centimeters long CNTs showed macroscale interwall superlubricious properties due to their defect-free structures. Ultralong, defect-free CNTs with controlled structures are highly desirable for many high-end applications. We hope that this Account will shed light on the controlled synthesis of ultralong CNTs with perfect structures and excellent properties. Moreover, the growth mechanism and controlled synthesis of ultralong CNTs with perfect structures also offers a good model for other one-dimensional nanomaterials.
Broadband quasi perfect absorption using chirped multi-layer porous materials
Directory of Open Access Journals (Sweden)
N. Jiménez
2016-12-01
Full Text Available This work theoretically analyzes the sound absorption properties of a chirped multi-layer porous material including transmission, in particular showing the broadband unidirectional absorption properties of the system. Using the combination of the impedance matching condition and the balance between the leakage and the intrinsic losses, the system is designed to have broadband unidirectional and quasi perfect absorption. The transfer and scattering matrix formalism, together with numerical simulations based on the finite element method are used to demonstrate the results showing excellent agreement between them. The proposed system allows to construct broadband sound absorbers with improved absorption in the low frequency regime using less amount of material than the complete bulk porous layer.
Broadband quasi perfect absorption using chirped multi-layer porous materials
Jiménez, N.; Romero-García, V.; Cebrecos, A.; Picó, R.; Sánchez-Morcillo, V. J.; Garcia-Raffi, L. M.
2016-12-01
This work theoretically analyzes the sound absorption properties of a chirped multi-layer porous material including transmission, in particular showing the broadband unidirectional absorption properties of the system. Using the combination of the impedance matching condition and the balance between the leakage and the intrinsic losses, the system is designed to have broadband unidirectional and quasi perfect absorption. The transfer and scattering matrix formalism, together with numerical simulations based on the finite element method are used to demonstrate the results showing excellent agreement between them. The proposed system allows to construct broadband sound absorbers with improved absorption in the low frequency regime using less amount of material than the complete bulk porous layer.
The Perfect Storm--Genetic Engineering, Science, and Ethics
Rollin, Bernard E.
2014-01-01
Uncertainty about ethics has been a major factor in societal rejection of biotechnology. Six factors help create a societal "perfect storm" regarding ethics and biotechnology: Social demand for ethical discussion; societal scientific illiteracy; poor social understanding of ethics; a "Gresham's Law for Ethics;" Scientific…
Helicity and other conservation laws in perfect fluid motion
Serre, Denis
2018-03-01
In this review paper, we discuss helicity from a geometrical point of view and see how it applies to the motion of a perfect fluid. We discuss its relation with the Hamiltonian structure, and then its extension to arbitrary space dimensions. We also comment about the existence of additional conservation laws for the Euler equation, and its unlikely integrability in Liouville's sense.
Effective vibration isolation system for perfect-crystal neutron interferometry
International Nuclear Information System (INIS)
Arthur, J.
1985-01-01
Perfect-crystal neutron interferometers are subject to degradation of their performance caused by vibrational accelerations. It is shown that the most seriously offending accelerations are rotational, and an effective and simple vibration isolation system that has been developed at the MIT Neutron Diffraction Laboratory is described
Perfect 2-colorings of the generalized Petersen graph
Indian Academy of Sciences (India)
Perfect 2-colorings of the generalized Petersen graph. MEHDI ALAEIYAN and HAMED KARAMI. ∗. School of Mathematics, Iran University of Science and Technology,. Narmak, Tehran 16846, Iran. *Corresponding author. E-mail: alaeiyan@iust.ac.ir; h_karami@iust.ac.ir. MS received 24 November 2014; revised 26 April ...
Hyper-Achievement, Perfection, and College Student Resilience
Eells, Gregory T.
2017-01-01
Over the past decade, there has been considerable attention given to college students' experience of pressure to pursue perfection through hyper-achievement and the psychological and emotional toll this process takes on them. The popular press has highlighted this phenomenon and raised specific questions about some of the related consequences like…
Indefinite and Continuative Interpretations of the English Present Perfect
Directory of Open Access Journals (Sweden)
Katarina Dea Žetko
2005-06-01
Full Text Available The objective of our paper is to demonstrate that the English present perfect is not by inherent meaning either indefinite or continuative. Notions like indefinite and continuative are contextdependent interpretations of whole constructions and their broader context. However, continuative interpretation can also be triggered by certain adverbials, negative constructions and verbs in the progressive form. But, even these factors do not always guarantee continuative interpretations. Construction, continuative meaning can be cancelled by the context in a broader sense, this fact being a proof that this meaning is merely an implicature. We will demonstrate how different factors interact and trigger either indefinite or continuative interpretations which are not inherent in the present perfect itself. Our paper will attempt to provide sufficient evidence that there is no indefinite/continuative distinction in the English present perfect, the inherent meaning or function of the present perfect is merely to locate the situation somewhere within a period that starts before the time of utterance and leads up to it.
Reflection of plane waves in an initially stressed perfectly ...
Indian Academy of Sciences (India)
Reflection of plane waves is studied at a free surface of a perfectly conducting transversely isotropic elastic solid half-space with initial stress. The governing equations are solved to obtain the velocity equation which indicates the existence of two quasi planar waves in the medium. Reflection coefficients and energy.
Quantum propagator in the presence of a perfectly reflecting wall
International Nuclear Information System (INIS)
Cacciari, Ilaria; Lantieri, Marco; Moretti, Paolo
2007-01-01
The transmission propagator for an arbitrary, finite range one-dimensional potential in the presence of a perfectly reflecting wall is calculated starting from the integral form of the Schroedinger equation. After a Laplace transform, the solution is obtained in a new and simple form by using matrix methods; we apply the results to an array of delta potentials
Perfect Power Prototype for Illinois Institute of Technology
Energy Technology Data Exchange (ETDEWEB)
Shahidehpour, Mohammad [Illinois Inst. Of Technology, Chicago, IL (United States)
2014-09-30
Starting in October 2008, Illinois Institute of Technology (IIT), in collaboration with over 20 participating members, led an extensive effort to develop, demonstrate, promote, and commercialize a microgrid system and offer supporting technologies that will achieve Perfect Power at the main campus of IIT. A Perfect Power system, as defined by the Galvin Electricity Initiative (GEI), is a system that cannot fail to meet the electric needs of the individual end-user. The Principle Investigator of this Perfect Power project was Dr. Mohammad Shahidehpour, Director of the Robert W. Galvin Center for Electricity Innovation at IIT. There were six overall objectives of the Perfect Power project: (1) Demonstrate the higher reliability introduced by the microgrid system at IIT; (2) Demonstrate the economics of microgrid operations; (3) Allow for a decrease of fifty percent (50%) of grid electricity load; (4) Create a permanent twenty percent (20%) decrease in peak load from 2007 level; (5) Defer planned substation through load reduction; (6) Offer a distribution system design that can be replicated in urban communities.
Unity and Duality in Barack Obama's "A More Perfect Union"
Terrill, Robert E.
2009-01-01
Faced with a racialized political crisis that threatened to derail his campaign to become the first African American president of the United States, Barack Obama delivered a speech on race titled "A More Perfect Union." He begins by portraying himself as an embodiment of double consciousness, but then invites his audience to share his…
Reflection of plane waves in an initially stressed perfectly ...
Indian Academy of Sciences (India)
Reflection of plane waves is studied at a free surface of a perfectly conducting transversely isotropic elastic solid half-space with initial stress. The governing equations are solved to obtain the velocity equation which indicates the existence of two quasi planar waves in the medium. Reflection coefficients and energy ratios ...
The Ideology of the Perfect Dictionary: How Efficient Can a ...
African Journals Online (AJOL)
The Ideology of the Perfect Dictionary: How Efficient Can a Dictionary Be? ... Not only have dictionary sales dramatically increased, but the variety of dictionaries and the competition between editors are also very much on the rise. ... FRENCH MONOLINGUAL DICTIONARIES, ELECTRONIC DICTIONARIES, CD-ROMS ...
Perfect Worlds : Utopian Fiction in China and the West
Fokkema, Douwe
2011-01-01
Perfect Worlds biedt een uitgebreide historische analyse van utopische verhalen in de Chinese en Euro-Amerikaanse traditie. Verschillende hoofdstukken gaan onder meer in op de kritiek van Thomas More op Plato, de Europese oriëntalistische speurtocht naar utopieën in China, Dostoevsky’s reactie op
Singularity free non-rotating cosmological solutions for perfect fluids ...
Indian Academy of Sciences (India)
Again an analysis leads to the Senovilla solution with. = ½. ¿ i.e.. Ф = ½. ¿p. 6. Conclusion. Our motivation was to examine whether non-singular non-rotating perfect fluid (with Ф = ) cosmologies exist besides those already discovered and presented in the literature. We have not been able to give an unequivocal answer but ...
Reprint Series: Prime Numbers and Perfect Numbers. RS-2.
Schaaf, William L., Ed.
This is one in a series of SMSG supplementary and enrichment pamphlets for high school students. This series makes available expository articles which appeared in a variety of mathematical periodicals. Topics covered include: (1) the prime numbers; (2) mathematical sieves; (3) the factorgram; and (4) perfect numbers. (MP)
The Perfect Storm—Genetic Engineering, Science, and Ethics
Rollin, Bernard E.
2012-07-01
Uncertainty about ethics has been a major factor in societal rejection of biotechnology. Six factors help create a societal "perfect storm" regarding ethics and biotechnology: Social demand for ethical discussion; societal scientific illiteracy; poor social understanding of ethics; a "Gresham's Law for Ethics;" Scientific Ideology; vested interests dominating ethical discussion. How this can be remedied is discussed.
Arbitrarily thin metamaterial structure for perfect absorption and giant magnification
DEFF Research Database (Denmark)
Jin, Yi; Xiao, Sanshui; Mortensen, N. Asger
2011-01-01
layer can perfectly absorb or giantly amplify an incident plane wave at a critical angle when the real parts of the permittivity and permeability of the metamaterial are zero while the absolute imaginary parts can be arbitrarily small. The metamaterial layer needs a totally reflective substrate...
Diamagnetic expansions for perfect quantum gases II: uniform bounds
DEFF Research Database (Denmark)
Philippe, Briet; Cornean, Horia; Louis, Delphine
Consider a charged, perfect quantum gas, in the effective mass approximation, and in the grand-canonical ensemble. We prove in this paper that the generalized magnetic susceptibilities admit the thermodynamic limit for all admissible fugacities, uniformly on compacts included in the analyticity d...
Creating the perfect intern anaesthesia rotation: a survey using ...
African Journals Online (AJOL)
Sedation and regional anaesthesia (4.5%); d. Negative comments (3.9%); e. Confining anaesthesia to .... comfortable with certain procedures, as a previous intern so perfectly summarised: 'I had no muscle memory for these sort of ... safe sedation skills and regional anaesthesia. Structure of the intern anaesthesia rotation.
Electronic and magnetic properties of perfect and defected germanium nanoribbons
International Nuclear Information System (INIS)
Pang Qing; Zhang Yan; Zhang Jianmin; Ji, Vincent; Xu Kewei
2011-01-01
Highlights: · Perfect AGeNRs are NM semiconductor with three-branch band gaps and decaying profiles. · Perfect ZGeNRs are AFM semiconductor with a decreasing band gap as width increases. · The band gap of AGeNRs can be tuned by mono- or di-vacancy at different positions. · Metallization can be realized in ZGeNRs by mono- or di-vacancy at different positions. · Magnetic properties of ZGeNRs depend closely upon the vacancy positions. - Abstract: The electronic and magnetic properties of both perfect and defected germanium nanoribbons (GeNRs) are investigated by using projector-augmented wave method based on density-functional theory. All the GeNRs with different edge shapes (armchair or zigzag) and widths are cut from the buckled Ge hexagonal sheet which is found to be semi-metallic as the planar graphene sheet. The results show that the perfect armchair GeNRs are nonmagnetic semiconductors and their band gaps exhibit three branches with decaying profiles, while the perfect zigzag GeNRs show the stable antiferromagnetic semiconducting ground state and their band gaps monotonously decrease with increasing ribbon width. These properties of the GeNRs are similar to graphene nanoribbons and should be important for designing new functional Ge-based nanodevices. The effects of the monovacancy or divacancy on the electronic and magnetic properties of the GeNRs are also considered. We found that the band gap of armchair GeNRs can be easily tuned by a monovancancy or divacancy at different positions, which provides a way of band gap engineering of armchair GeNRs for actual applications. Different from the defected armchair GeNRs, the metallization can be realized in zigzag GeNRs by a monovacancy or a divacancy, however, their magnetic properties depend closely upon the vacancy positions.
INFORMATION SYSTEMS AUDIT CURRICULA CONTENT MATCHING
Directory of Open Access Journals (Sweden)
Vasile-Daniel CARDOȘ
2014-11-01
Full Text Available Financial and internal auditors must cope with the challenge of performing their mission in technology enhanced environment. In this article we match the information technology description found in the International Federation of Accountants (IFAC and the Institute of Internal Auditors (IIA curricula against the Model Curriculum issued by the Information Systems Audit and Control Association (ISACA. By reviewing these three curricula, we matched the content in the ISACA Model Curriculum with the IFAC International Education Practice Statement 2 and the IIAs’ Global Model Internal Audit Curriculum. In the IFAC and IIA Curriculum there are 16 content elements, out of 19 possible, which match, in their description, the ISACA Model Curriculum’s content. We noticed that a candidate who graduates an IFAC or IIA compliant program acquire IS auditing competences similar to the specific content of the ISACA model curriculum but less than the requirements for a professional information systems auditor.
Dideriksen, Jakob Lund; Feeney, Daniel F; Almuklass, Awad M; Enoka, Roger M
2017-08-01
Force trajectories during isometric force-matching tasks involving isometric contractions vary substantially across individuals. In this study, we investigated if this variability can be explained by discrete time proportional, integral, derivative (PID) control algorithms with varying model parameters. To this end, we analyzed the pinch force trajectories of 24 subjects performing two rapid force-matching tasks with visual feedback. Both tasks involved isometric contractions to a target force of 10% maximal voluntary contraction. One task involved a single action (pinch) and the other required a double action (concurrent pinch and wrist extension). 50,000 force trajectories were simulated with a computational neuromuscular model whose input was determined by a PID controller with different PID gains and frequencies at which the controller adjusted muscle commands. The goal was to find the best match between each experimental force trajectory and all simulated trajectories. It was possible to identify one realization of the PID controller that matched the experimental force produced during each task for most subjects (average index of similarity: 0.87 ± 0.12; 1 = perfect similarity). The similarities for both tasks were significantly greater than that would be expected by chance (single action: p = 0.01; double action: p = 0.04). Furthermore, the identified control frequencies in the simulated PID controller with the greatest similarities decreased as task difficulty increased (single action: 4.0 ± 1.8 Hz; double action: 3.1 ± 1.3 Hz). Overall, the results indicate that discrete time PID controllers are realistic models for the neural control of force in rapid force-matching tasks involving isometric contractions.
A proactive condition-based maintenance strategy with both perfect and imperfect maintenance actions
International Nuclear Information System (INIS)
Do, Phuc; Voisin, Alexandre; Levrat, Eric; Iung, Benoit
2015-01-01
This paper deals with a proactive condition-based maintenance (CBM) considering both perfect and imperfect maintenance actions for a deteriorating system. Perfect maintenance actions restore completely the system to the ‘as good as new’ state. Their related cost are however often high. The first objective of the paper is to investigate the impacts of imperfect maintenance actions. In fact, both positive and negative impacts are considered. Positive impact means that the imperfect maintenance cost is usually low. Negative impact implies that (i) the imperfect maintenance restores a system to a state between good-as-new and bad-as-old and (ii) each imperfect preventive action may accelerate the speed of the system's deterioration process. The second objective of the paper is to propose an adaptive maintenance policy which can help to select optimally maintenance actions (perfect or imperfect actions), if needed, at each inspection time. Moreover, the time interval between two successive inspection points is determined according to a remaining useful life (RUL) based-inspection policy. To illustrate the use of the proposed maintenance policy, a numerical example finally is introduced. - Highlights: • A new imperfect maintenance model for deterioration system is proposed. • Both positive and negative impacts of an imperfect maintenance action are investigated. • An adaptive condition-based maintenance policy is introduced. • The optimal number of useful imperfect maintenance actions for each life cycle is optimally provided
Fields, Peter D.; Bourgeois, Yann; Du Pasquier, Louis; Ebert, Dieter
2017-01-01
Negative frequency-dependent selection (NFDS) is an evolutionary mechanism suggested to govern host-parasite coevolution and the maintenance of genetic diversity at host resistance loci, such as the vertebrate MHC and R-genes in plants. Matching-allele interactions of hosts and parasites that prevent the emergence of host and parasite genotypes that are universally resistant and infective are a genetic mechanism predicted to underpin NFDS. The underlying genetics of matching-allele interactions are unknown even in host-parasite systems with empirical support for coevolution by NFDS, as is the case for the planktonic crustacean Daphnia magna and the bacterial pathogen Pasteuria ramosa. We fine-map one locus associated with D. magna resistance to P. ramosa and genetically characterize two haplotypes of the Pasteuria resistance (PR-) locus using de novo genome and transcriptome sequencing. Sequence comparison of PR-locus haplotypes finds dramatic structural polymorphisms between PR-locus haplotypes including a large portion of each haplotype being composed of non-homologous sequences resulting in haplotypes differing in size by 66 kb. The high divergence of PR-locus haplotypes suggest a history of multiple, diverse and repeated instances of structural mutation events and restricted recombination. Annotation of the haplotypes reveals striking differences in gene content. In particular, a group of glycosyltransferase genes that is present in the susceptible but absent in the resistant haplotype. Moreover, in natural populations, we find that the PR-locus polymorphism is associated with variation in resistance to different P. ramosa genotypes, pointing to the PR-locus polymorphism as being responsible for the matching-allele interactions that have been previously described for this system. Our results conclusively identify a genetic basis for the matching-allele interaction observed in a coevolving host-parasite system and provide a first insight into its molecular basis
A THz plasmonics perfect absorber and Fabry-Perot cavity mechanism (Conference Presentation)
Zhou, Jiangfeng; Bhattarai, Khagendra; Silva, Sinhara; Jeon, Jiyeon; Kim, Junoh; Lee, Sang Jun; Ku, Zahyun
2016-10-01
The plasmonic metamaterial perfect absorber (MPA) is a recently developed branch of metamaterial which exhibits nearly unity absorption within certain frequency range.[1-6] The optically thin MPA possesses characteristic features of angular-independence, high Q-factor and strong field localization that have inspired a wide range of applications including electromagnetic wave absorption,[3, 7, 8] spatial[6] and spectral[5] modulation of light,[9] selective thermal emission,[9] thermal detecting[10] and refractive index sensing for gas[11] and liquid[12, 13] targets. In this work, we demonstrate a MPA working at terahertz (THz) regime and characterize it using an ultrafast THz time-domain spectroscopy (THz-TDS). Our study reveal an ultra-thin Fabry-Perot cavity mechanism compared to the impedance matching mechanism widely adopted in previous study [1-6]. Our results also shows higher-order resonances when the cavities length increases. These higher order modes exhibits much larger Q-factor that can benefit potential sensing and imaging applications. [1] C. M. Watts, X. L. Liu, and W. J. Padilla, "Metamaterial Electromagnetic Wave Absorbers," Advanced Materials, vol. 24, pp. 98-120, Jun 19 2012. [2] M. Hedayati, F. Faupel, and M. Elbahri, "Review of Plasmonic Nanocomposite Metamaterial Absorber," Materials, vol. 7, pp. 1221-1248, 2014. [3] N. I. Landy, S. Sajuyigbe, J. J. Mock, D. R. Smith, and W. J. Padilla, "Perfect metamaterial absorber," Physical Review Letters, vol. 100, p. 207402, May 23 2008. [4] H. R. Seren, G. R. Keiser, L. Cao, J. Zhang, A. C. Strikwerda, K. Fan, et al., "Optically Modulated Multiband Terahertz Perfect Absorber," Advanced Optical Materials, vol. 2, pp. 1221-1226, 2014. [5] D. Shrekenhamer, J. Montoya, S. Krishna, and W. J. Padilla, "Four-Color Metamaterial Absorber THz Spatial Light Modulator," Advanced Optical Materials, vol. 1, pp. 905-909, 2013. [6] S. Savo, D. Shrekenhamer, and W. J. Padilla, "Liquid Crystal Metamaterial Absorber Spatial
Job Searchers, Job Matches and the Elasticity of Matching
Broersma, L.; van Ours, J.C.
1998-01-01
This paper stresses the importance of a specification of the matching function in which the measure of job matches corresponds to the measure of job searchers. In many empirical studies on the matching function this requirement has not been fulfilled because it is difficult to find information about
Characteristic Evolution and Matching
Directory of Open Access Journals (Sweden)
Winicour Jeffrey
2009-04-01
Full Text Available I review the development of numerical evolution codes for general relativity based upon the characteristic initial value problem. Progress is traced from the early stage of 1D feasibility studies to 2D axisymmetric codes that accurately simulate the oscillations and gravitational collapse of relativistic stars and to current 3D codes that provide pieces of a binary black hole spacetime. Cauchy codes have now been successful at simulating all aspects of the binary black hole problem inside an artificially constructed outer boundary. A prime application of characteristic evolution is to eliminate the role of this artificial outer boundary via Cauchy-characteristic matching, by which the radiated waveform can be computed at null infinity. Progress in this direction is discussed.
Electromagnetic wave matching device
International Nuclear Information System (INIS)
Hirata, Yosuke; Mitsunaka, Yoshika; Hayashi, Ken-ichi; Ito, Yasuyuki.
1997-01-01
The present invention provides an electromagnetic wave matching capable of reducing a cost for the transmission system in a system of using electromagnetic waves for plasma heating of a thermonuclear reactor. Namely, incident electromagnetic waves are reflected by using a plurality of phase correction mirrors. The reflected electromagnetic waves are connected to an external transmission system through an exit. The phase correction mirrors have such a shape to receive a plurality of beam-like electromagnetic waves and output electromagnetic waves by the number different from the number of the received electromagnetic wave beams having a predetermined distribution. Further, at least two of the phase correction mirrors have such a shape to change the phase of the electromagnetic waves beams incident to the reflection surface of the phase correction mirrors by a predetermined amount corresponding to the position of the reflection surface. Then, the cost for transmission system can greatly be reduced. (I.S.)
MatchIt: Nonparametric Preprocessing for Parametric Causal Inference
Directory of Open Access Journals (Sweden)
Daniel Ho
2011-08-01
Full Text Available MatchIt implements the suggestions of Ho, Imai, King, and Stuart (2007 for improving parametric statistical models by preprocessing data with nonparametric matching methods. MatchIt implements a wide range of sophisticated matching methods, making it possible to greatly reduce the dependence of causal inferences on hard-to-justify, but commonly made, statistical modeling assumptions. The software also easily fits into existing research practices since, after preprocessing data with MatchIt, researchers can use whatever parametric model they would have used without MatchIt, but produce inferences with substantially more robustness and less sensitivity to modeling assumptions. MatchIt is an R program, and also works seamlessly with Zelig.
Quantity precommitment and price matching
DEFF Research Database (Denmark)
Tumennasan, Norovsambuu
We revisit the question of whether price matching is anti-competitive in a capacity constrained duopoly setting. We show that the effect of price matching depends on capacity. Specifically, price matching has no effect when capacity is relatively low, but it benefits the firms when capacity...... is relatively high. Interestingly, when capacity is in an intermediate range, price matching benefits only the small firm but does not affect the large firm in any way. Therefore, one has to consider capacity seriously when evaluating if price matching is anti-competitive. If the firms choose their capacities...... simultaneously before pricing decisions, then the effect of price matching is either pro-competitive or ambiguous. We show that if the cost of capacity is high, then price matching can only (weakly) decrease the market price. On the other hand, if the cost of capacity is low, then the effect of price matching...
PREDICTING THE MATCH OUTCOME IN ONE DAY INTERNATIONAL CRICKET MATCHES, WHILE THE GAME IS IN PROGRESS
Directory of Open Access Journals (Sweden)
Michael Bailey
2006-12-01
Full Text Available Millions of dollars are wagered on the outcome of one day international (ODI cricket matches, with a large percentage of bets occurring after the game has commenced. Using match information gathered from all 2200 ODI matches played prior to January 2005, a range of variables that could independently explain statistically significant proportions of variation associated with the predicted run totals and match outcomes were created. Such variables include home ground advantage, past performances, match experience, performance at the specific venue, performance against the specific opposition, experience at the specific venue and current form. Using a multiple linear regression model, prediction variables were numerically weighted according to statistical significance and used to predict the match outcome. With the use of the Duckworth-Lewis method to determine resources remaining, at the end of each completed over, the predicted run total of the batting team could be updated to provide a more accurate prediction of the match outcome. By applying this prediction approach to a holdout sample of matches, the efficiency of the "in the run" wagering market could be assessed. Preliminary results suggest that the market is prone to overreact to events occurring throughout the course of the match, thus creating brief inefficiencies in the wagering market
A Particular Type of Present Perfect Tense in Shahnameh
Directory of Open Access Journals (Sweden)
Moharram Rezayati Kishekhaleh
2012-04-01
Full Text Available Abstract The Shahnameh, the precious and eternal epic poem of Ferdosi, in the ocean of Persian literature is a deep and immense sea. It is full of shining pearls of Iranian culture, that studying of them could be used by researchers of Persian language and literature for various dimensions of literary, historical, social, mythical, religious, and linguistics, etc. This subject allocates for little part of linguistic characteristics i.e. present perfect tense and its kinds. Initially the history of research was considered briefly then the patterns of structure of this verb were studying in the language of ancient Persian, middle Persian and Dari Persian. We eventually, according to samples from the Shahnameh, scattered notions of researchers and their adding up, describe a certain kind of present perfect tense which, its history of structure and application in addition to Soghdi, Khwarizmi and Pahlavi languages, could be recognized at some today Iranian dialects
A Particular Type of Present Perfect Tense in Shahnameh
Directory of Open Access Journals (Sweden)
Moharram Rezayati Kishekhaleh
2012-03-01
Full Text Available Abstract The Shahnameh, the precious and eternal epic poem of Ferdosi, in the ocean of Persian literature is a deep and immense sea. It is full of shining pearls of Iranian culture, that studying of them could be used by researchers of Persian language and literature for various dimensions of literary, historical, social, mythical, religious, and linguistics, etc. This subject allocates for little part of linguistic characteristics i.e. present perfect tense and its kinds. Initially the history of research was considered briefly then the patterns of structure of this verb were studying in the language of ancient Persian, middle Persian and Dari Persian. We eventually, according to samples from the Shahnameh, scattered notions of researchers and their adding up, describe a certain kind of present perfect tense which, its history of structure and application in addition to Soghdi, Khwarizmi and Pahlavi languages, could be recognized at some today Iranian dialects
Perfect quantum multiple-unicast network coding protocol
Li, Dan-Dan; Gao, Fei; Qin, Su-Juan; Wen, Qiao-Yan
2018-01-01
In order to realize long-distance and large-scale quantum communication, it is natural to utilize quantum repeater. For a general quantum multiple-unicast network, it is still puzzling how to complete communication tasks perfectly with less resources such as registers. In this paper, we solve this problem. By applying quantum repeaters to multiple-unicast communication problem, we give encoding-decoding schemes for source nodes, internal ones and target ones, respectively. Source-target nodes share EPR pairs by using our encoding-decoding schemes over quantum multiple-unicast network. Furthermore, quantum communication can be accomplished perfectly via teleportation. Compared with existed schemes, our schemes can reduce resource consumption and realize long-distance transmission of quantum information.
On a ''conformal'' perfect fluid in the classical vacuum
International Nuclear Information System (INIS)
Culetu, H.
1993-02-01
A possible existence of a conformal perfect fluid in the classical vacuum is investigated in this letter. It is shown, contrary to Madsen's opinion, that the scalar field stress tensor acquires a perfect fluid form even with a nonminimal coupling (ξ = 1/6) in the Einstein Lagrangian, provided the geometry is the Lorentzian analogue of the Euclidean Hawking wormhole. In addition, our T μν equals (up to a constant factor) the vacuum expectation value of the Fulling stress tensor for a massless scalar field and Visser's one concerning transversible wormholes. On the other side of the light cone, there is a coordinate system (the dimensionally reduced Witten bubble) where the stress tensor becomes diagonal. (author). 13 refs
Thermodynamics of perfect fluids from scalar field theory
Ballesteros, Guillermo; Pilo, Luigi
2016-01-01
The low-energy dynamics of relativistic continuous media is given by a shift-symmetric effective theory of four scalar fields. These scalars describe the embedding in spacetime of the medium and play the role of Stuckelberg fields for spontaneously broken spatial and time translations. Perfect fluids are selected imposing a stronger symmetry group or reducing the field content to a single scalar. We explore the relation between the field theory description of perfect fluids to thermodynamics. By drawing the correspondence between the allowed operators at leading order in derivatives and the thermodynamic variables, we find that a complete thermodynamic picture requires the four Stuckelberg fields. We show that thermodynamic stability plus the null energy condition imply dynamical stability. We also argue that a consistent thermodynamic interpretation is not possible if any of the shift symmetries is explicitly broken.
Fast algorithms for approximate circular string matching.
Barton, Carl; Iliopoulos, Costas S; Pissis, Solon P
2014-03-22
Circular string matching is a problem which naturally arises in many biological contexts. It consists in finding all occurrences of the rotations of a pattern of length m in a text of length n. There exist optimal average-case algorithms for exact circular string matching. Approximate circular string matching is a rather undeveloped area. In this article, we present a suboptimal average-case algorithm for exact circular string matching requiring time O(n). Based on our solution for the exact case, we present two fast average-case algorithms for approximate circular string matching with k-mismatches, under the Hamming distance model, requiring time O(n) for moderate values of k, that is k=O(m/logm). We show how the same results can be easily obtained under the edit distance model. The presented algorithms are also implemented as library functions. Experimental results demonstrate that the functions provided in this library accelerate the computations by more than three orders of magnitude compared to a naïve approach. We present two fast average-case algorithms for approximate circular string matching with k-mismatches; and show that they also perform very well in practice. The importance of our contribution is underlined by the fact that the provided functions may be seamlessly integrated into any biological pipeline. The source code of the library is freely available at http://www.inf.kcl.ac.uk/research/projects/asmf/.
Quality strategies implemented within the tourism agency Perfect Tour
Directory of Open Access Journals (Sweden)
Madar, A.
2012-01-01
Full Text Available The paper presents the quality strategies adopted by the tourism agency Perfect Tour. The most important advantages of the Romanian agency in comparison with its competitors are: the focus on high quality services, cooperation with other international agencies, entering new fields like medical tourism and sole representative of Disneyland Paris. The strategies adopted explain the good financial results even in the period of crisis.
A psychogenic dystonia perfect responsive to antidepressant treatment.
Volkan Solmaz; Durdane Aksoy; Betul Cevik; Semiha Gulsum Kurt; Elmas Pekdas; Sema inanir
2014-01-01
After ruling out of organic causes, movement disorders are named as psychogenic movement disorders, it can mimic perfectly Organic movement disorders, but with a good history, clinical observations and detailed examination is very helpful in the diagnosis of this disease. In here we will present a 15 years old male patient, he was complaining of urinary incontinence at night, emerging dystonic posture especially in crowded environments, eating, and during activities that require attention, fo...
Perfect Asset Lifecycle Management. Breaking through old ideas
International Nuclear Information System (INIS)
Roestenberg, B.; De Croon, J.; Broere, E.; TeMeerman, W.; Meijer, D.
2003-01-01
The new idea described in this book provides practical tools to use capital assets in a cost-effective way. Value can be created over the life cycle of such assets. Perfect Asset Lifecycle Management (PALM) outlines a perspective for socially justified enterprising. PALM has been tested in the energy sector where liberalization of the market and the continuity of services appear to be on bad terms. According to the authors PALM can also be applied in other sectors [nl
Perfect independent sets with respect to infinitely many relations
Czech Academy of Sciences Publication Activity Database
Doležal, Martin; Kubiś, Wieslaw
2016-01-01
Roč. 55, č. 7 (2016), s. 847-856 ISSN 0933-5846 R&D Projects: GA ČR(CZ) GA14-07880S Institutional support: RVO:67985840 Keywords : perfect clique * free subgroup * open relation Subject RIV: BA - General Mathematics Impact factor: 0.394, year: 2016 http://link.springer.com/article/10.1007%2Fs00153-016-0498-3
Quantum states representing perfectly secure bits are always distillable
International Nuclear Information System (INIS)
Horodecki, Pawel; Augusiak, Remigiusz
2006-01-01
It is proven that recently introduced states with perfectly secure bits of cryptographic key (private states representing secure bit) [K. Horodecki et al., Phys. Rev. Lett. 94, 160502 (2005)] as well as its multipartite and higher dimension generalizations always represent distillable entanglement. The corresponding lower bounds on distillable entanglement are provided. We also present a simple alternative proof that for any bipartite quantum state entanglement cost is an upper bound on a distillable cryptographic key in a bipartite scenario
Overlapped illusion optics: a perfect lens brings a brighter feature
Energy Technology Data Exchange (ETDEWEB)
Xu Yadong; Gao Lei; Chen Huanyang [School of Physical Science and Technology, Soochow University, Suzhou, Jiangsu 215006 (China); Du Shengwang, E-mail: kenyon@ust.hk [Department of Physics, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon (Hong Kong)
2011-02-15
In this paper, we show that a perfect lens can be employed to make multiple objects appear like only one object in the far field, leading to a new concept in illusion optics. Numerical simulations have been performed to verify the functionalities for both passive and active objects. The conceptual device can be utilized to enhance the illumination brightness for both incoherent and coherent systems.
Overlapped illusion optics: a perfect lens brings a brighter feature
International Nuclear Information System (INIS)
Xu Yadong; Gao Lei; Chen Huanyang; Du Shengwang
2011-01-01
In this paper, we show that a perfect lens can be employed to make multiple objects appear like only one object in the far field, leading to a new concept in illusion optics. Numerical simulations have been performed to verify the functionalities for both passive and active objects. The conceptual device can be utilized to enhance the illumination brightness for both incoherent and coherent systems.
Comment on ''Perfect imaging with positive refraction in three dimensions''
International Nuclear Information System (INIS)
Merlin, R.
2010-01-01
Leonhardt and Philbin [Phys. Rev. A 81, 011804(R) (2010)] have recently constructed a mathematical proof that the Maxwell's fish-eye lens provides perfect imaging of electromagnetic waves without negative refraction. In this comment, we argue that the unlimited resolution is an artifact of having introduced an unphysical drain at the position of the geometrical image. The correct solution gives focusing consistent with the standard diffraction limit.
Shape-matching soft mechanical metamaterials.
Mirzaali, M J; Janbaz, S; Strano, M; Vergani, L; Zadpoor, A A
2018-01-17
Architectured materials with rationally designed geometries could be used to create mechanical metamaterials with unprecedented or rare properties and functionalities. Here, we introduce "shape-matching" metamaterials where the geometry of cellular structures comprising auxetic and conventional unit cells is designed so as to achieve a pre-defined shape upon deformation. We used computational models to forward-map the space of planar shapes to the space of geometrical designs. The validity of the underlying computational models was first demonstrated by comparing their predictions with experimental observations on specimens fabricated with indirect additive manufacturing. The forward-maps were then used to devise the geometry of cellular structures that approximate the arbitrary shapes described by random Fourier's series. Finally, we show that the presented metamaterials could match the contours of three real objects including a scapula model, a pumpkin, and a Delft Blue pottery piece. Shape-matching materials have potential applications in soft robotics and wearable (medical) devices.
Color matching in facial prosthetics: A systematic review.
Ranabhatt, Rani; Singh, Kamleshwar; Siddharth, Ramashanker; Tripathi, Shuchi; Arya, Deeksha
2017-01-01
Color matching to the surrounding skin is extremely important in patients wearing maxillofacial prostheses. It is of utmost importance to know the different techniques of color matching and coloring in maxillofacial prostheses. The purpose of this study is to review the literature data with regard to color matching in maxillofacial prosthetics. An electronic search of peer review restricted to English language dental literature was conducted to identify the relevant scientific article on color matching and coloring in maxillofacial prostheses. The publication year was up to December 2015 so that the search could include all the articles provided in that particular database. Two independent observers independently read the abstracts and later preselected full-text articles. A full-text review was carried out only for 15 articles. Out of the 15 articles, 7 were related to coloring using tinting, spraying, milling, and use of commercial cosmetics. Three studies were related to shade matching in maxillofacial prostheses. Two studies conducted the measurement of color in maxillofacial prostheses. Only one study had explained color and its relevance in maxillofacial prosthetics. Only one study was done for reproducing silicone shade guide matching Indian skin color. In addition, a single pilot study was done to measure facial skin and lip color in a human population sample stratified by race, gender, and age. Currently, there is no evidence discussing the best technique available for perfectly matching the color for the fabrication of maxillofacial prostheses. However, the latest instruments such as spectrophotometer and colorimeters are believed to have improved efficiency in matching the color.
Scheers, B.; Bloemen, S.; Mühleisen, H.; Schellart, P.; van Elteren, A.; Kersten, M.; Groot, P. J.
2018-04-01
Coming high-cadence wide-field optical telescopes will image hundreds of thousands of sources per minute. Besides inspecting the near real-time data streams for transient and variability events, the accumulated data archive is a wealthy laboratory for making complementary scientific discoveries. The goal of this work is to optimise column-oriented database techniques to enable the construction of a full-source and light-curve database for large-scale surveys, that is accessible by the astronomical community. We adopted LOFAR's Transients Pipeline as the baseline and modified it to enable the processing of optical images that have much higher source densities. The pipeline adds new source lists to the archive database, while cross-matching them with the known cataloguedsources in order to build a full light-curve archive. We investigated several techniques of indexing and partitioning the largest tables, allowing for faster positional source look-ups in the cross matching algorithms. We monitored all query run times in long-term pipeline runs where we processed a subset of IPHAS data that have image source density peaks over 170,000 per field of view (500,000 deg-2). Our analysis demonstrates that horizontal table partitions of declination widths of one-degree control the query run times. Usage of an index strategy where the partitions are densely sorted according to source declination yields another improvement. Most queries run in sublinear time and a few (processing IPHAS data is 25 s.
Computational Modeling of Geoelectrical Soundings using PML-FDTD
Ribeiro, Luísa F.; Novo, Marcela S.
2017-01-01
Abstract The Finite-Difference Time-Domain (FDTD) method was applied in order to analyze the transient responses of geoelectrical soundings that use circular electric dipole (CED) as source over stratified formations. The model was developed in cylindrical coordinates and a perfectly matched layer (PML) was incorporated to the domain to absorb wave reflections at computational grid boundaries. Numeric results are validated with analytic solutions. Comparisons between the transient response of...
Using crosswell data to enhance history matching
Ravanelli, Fabio M.
2014-01-01
One of the most challenging tasks in the oil industry is the production of reliable reservoir forecast models. Due to different sources of uncertainties in the numerical models and inputs, reservoir simulations are often only crude approximations of the reality. This problem is mitigated by conditioning the model with data through data assimilation, a process known in the oil industry as history matching. Several recent advances are being used to improve history matching reliability, notably the use of time-lapse data and advanced data assimilation techniques. One of the most promising data assimilation techniques employed in the industry is the ensemble Kalman filter (EnKF) because of its ability to deal with non-linear models at reasonable computational cost. In this paper we study the use of crosswell seismic data as an alternative to 4D seismic surveys in areas where it is not possible to re-shoot seismic. A synthetic reservoir model is used in a history matching study designed better estimate porosity and permeability distributions and improve the quality of the model to predict future field performance. This study is divided in three parts: First the use of production data only is evaluated (baseline for benchmark). Second the benefits of using production and 4D seismic data are assessed. Finally, a new conceptual idea is proposed to obtain time-lapse information for history matching. The use of crosswell time-lapse seismic tomography to map velocities in the interwell region is demonstrated as a potential tool to ensure survey reproducibility and low acquisition cost when compared with full scale surface surveys. Our numerical simulations show that the proposed method provides promising history matching results leading to similar estimation error reductions when compared with conventional history matched surface seismic data.
Organizations must match assets
International Nuclear Information System (INIS)
Carley, G.R.
1991-01-01
The unprofitable state of the Canadian oil industry, the adverse economic environment, the difficulty of finding capital, and the diminishing resources of conventional lighter crude oil make it necessary for Canadian oil companies to match their organizations and their financing to their assets. This is illustrated according to the experience of Saskoil, a Saskatchewan oil and gas company. An increasing production of oil and natural gas, and an increasing amount of new oil production as heavy oil, led to organizational changes such as the purchase of an asphalt plant to provide the company with downstream experience, establishing a working group to explore and develop heavy oil resources, and forming a company to manage non-core assets. The latter company, Pasqua Resources, manages assets such as small properties and ownership interests in order to increase the operating efficiency of Saskoil. Pasqua provides Saskoil with a corporate and organizational vehicle to accommodate partnerships and joint venture capital invested in property purchase opportunities, and to manage any of Saskoil's divestiture activities
Characteristic Evolution and Matching
Directory of Open Access Journals (Sweden)
Jeffrey Winicour
2012-01-01
Full Text Available I review the development of numerical evolution codes for general relativity based upon the characteristic initial-value problem. Progress in characteristic evolution is traced from the early stage of 1D feasibility studies to 2D-axisymmetric codes that accurately simulate the oscillations and gravitational collapse of relativistic stars and to current 3D codes that provide pieces of a binary black-hole spacetime. Cauchy codes have now been successful at simulating all aspects of the binary black-hole problem inside an artificially constructed outer boundary. A prime application of characteristic evolution is to extend such simulations to null infinity where the waveform from the binary inspiral and merger can be unambiguously computed. This has now been accomplished by Cauchy-characteristic extraction, where data for the characteristic evolution is supplied by Cauchy data on an extraction worldtube inside the artificial outer boundary. The ultimate application of characteristic evolution is to eliminate the role of this outer boundary by constructing a global solution via Cauchy-characteristic matching. Progress in this direction is discussed.
Huang, X.; Hu, K.; Ling, X.; Zhang, Y.; Lu, Z.; Zhou, G.
2017-09-01
This paper introduces a novel global patch matching method that focuses on how to remove fronto-parallel bias and obtain continuous smooth surfaces with assuming that the scenes covered by stereos are piecewise continuous. Firstly, simple linear iterative cluster method (SLIC) is used to segment the base image into a series of patches. Then, a global energy function, which consists of a data term and a smoothness term, is built on the patches. The data term is the second-order Taylor expansion of correlation coefficients, and the smoothness term is built by combing connectivity constraints and the coplanarity constraints are combined to construct the smoothness term. Finally, the global energy function can be built by combining the data term and the smoothness term. We rewrite the global energy function in a quadratic matrix function, and use least square methods to obtain the optimal solution. Experiments on Adirondack stereo and Motorcycle stereo of Middlebury benchmark show that the proposed method can remove fronto-parallel bias effectively, and produce continuous smooth surfaces.
Monetary Exchange with Multilateral Matching
DEFF Research Database (Denmark)
Julien, Benoît; Kennes, John; King, Ian
This paper analyzes monetary exchange in a search model allowing for multilateral matches to be formed, according to a standard urn-ballprocess. We consider three physical environments: indivisible goods and money, divisible goods and indivisible money, and divisible goods and money. We compare....... In particular, surplus maximization can be achieved in this setting, in equilibrium, with a positive money supply. Moreover, with flexible prices and directed search, the first best allocation can be attained through price posting or through auctions with lotteries, but not through auctions without lotteries....... Finally, analysis of the case of divisible goods and money can be performed without the assumption of large families (as in Shi (1997)) or the day and night structure of Lagos and Wright (2005)....
Beyond the perfect fluid hypothesis for the dark energy equation of state
International Nuclear Information System (INIS)
Cardone, V.F.; Troisi, A.; Tortora, C.; Capozziello, S.
2006-01-01
Abandoning the perfect fluid hypothesis, we investigate here the possibility that the dark energy equation of state (EoS) w is a nonlinear function of the energy density ρ. To this aim, we consider four different EoS describing classical fluids near thermodynamical critical points and discuss the main features of cosmological models made out of dust matter and a dark energy term with the given EoS. Each model is tested against the data on the dimensionless coordinate distance to Type Ia Supernovae and radio galaxies, the shift and the acoustic peak parameters and the positions of the first three peaks in the anisotropy spectrum of the comic microwave background radiation. We propose a possible interpretation of each model in the framework of scalar field quintessence determining the shape of the self-interaction potential V(φ) that gives rise to each one of the considered thermodynamical EoS. As a general result, we demonstrate that replacing the perfect fluid EoS with more general expressions gives both the possibility of successfully solving the problem of cosmic acceleration escaping the resort to phantom models
On the uniqueness of static perfect-fluid solutions in general relativity
International Nuclear Information System (INIS)
Beig, R.; Simon, W.
1990-01-01
Following earlier work of Masood-ul-Alam, we consider a uniqueness problem for nonrotating stellar models. Given a static, asymptotically flat perfect-fluid spacetime with barotropic equation of state ρ(p), and given another such spacetime which is spherically symmetric and has the same ρ(p) and the same surface potential: we prove that both are identical provided ρ(p) satisfies a certain differential inequality. This inequality is more natural and less restrictive that the conditions required by Masood-ul-Alam. 30 refs. (Authors)
New class of inhomogeneous cosmological perfect-fluid solutions without big-bang singularity
Energy Technology Data Exchange (ETDEWEB)
Senovilla, J.M.M. (Grupo de Fisica Teorica, Departamento de Fisica, Ingenieria y Radiologia Medica, Facultad de Ciencias, Universidad de Salamanca, 37008 Salmanaca (Spain))
1990-05-07
A new class of exact solutions to Einstein's field equations with a perfect-fluid source is presented. The solutions describe spatially inhomogeneous cosmological models and have a realistic equation of state {ital p}={rho}/3. The properties of the solutions are discussed. The most remarkable feature is the absence of an initial singularity, the curvature and matter invariants being regular and smooth everywhere. We also present an alternative interpretation of the solution as a globally regular cylindrically symmetric space-time.
Automatic Matching of High Resolution Satellite Images Based on RFM
Directory of Open Access Journals (Sweden)
JI Shunping
2016-02-01
Full Text Available A matching method for high resolution satellite images based on RFM is presented.Firstly,the RFM parameters are used to predict the initial parallax of corresponding points and the prediction accuracy is analyzed.Secondly,the approximate epipolar equation is constructed based on projection tracking and its accuracy is analyzed.Thirdly,approximate 1D image matching is executed on pyramid images and least square matching on base images.At last RANSAC is imbedded to eliminate mis-matching points and matching results are obtained.Test results verified the method more robust and with higher matching rate,compared to 2D gray correlation method and the popular SIFT matching method,and the method preferably solved the question of high resolution satellite image matching with different stereo model,different time and large rotation images.
International Nuclear Information System (INIS)
Tsoukalas, L.
2002-01-01
Funding used to support a portion of the Nuclear Engineering Educational Activities. Upgrade of teaching labs, student support to attend professional conferences, salary support for graduate students. The US Department of Energy (DOE) has funded Purdue University School of Nuclear Engineering during the period of five academic years covered in this report starting in the academic year 1996-97 and ending in the academic year 2000-2001. The total amount of funding for the grant received from DOE is $416K. In the 1990's, Nuclear Engineering Education in the US experienced a significant slow down. Student enrollment, research support, number of degrees at all levels (BS, MS, and PhD), number of accredited programs, University Research and Training Reactors, all went through a decline to alarmingly low levels. Several departments closed down, while some were amalgamated with other academic units (Mechanical Engineering, Chemical Engineering, etc). The School of Nuclear Engineering at Purdue University faced a major challenge when in the mid 90's our total undergraduate enrollment for the Sophomore, Junior and Senior Years dropped in the low 30's. The DOE Matching Grant program greatly strengthened Purdue's commitment to the Nuclear Engineering discipline and has helped to dramatically improve our undergraduate and graduate enrollment, attract new faculty and raise the School of Nuclear Engineering status within the University and in the National scene (our undergraduate enrollment has actually tripled and stands at an all time high of over 90 students; total enrollment currently exceeds 110 students). In this final technical report we outline and summarize how the grant was expended at Purdue University
Directory of Open Access Journals (Sweden)
Tingting Li
2017-12-01
Full Text Available Since they can provide a natural and flexible description of nonlinear dynamic behavior of complex system, Agent-based models (ABM have been commonly used for immune system simulation. However, it is crucial for ABM to obtain an appropriate estimation for the key parameters of the model by incorporating experimental data. In this paper, a systematic procedure for immune system simulation by integrating the ABM and regression method under the framework of history matching is developed. A novel parameter estimation method by incorporating the experiment data for the simulator ABM during the procedure is proposed. First, we employ ABM as simulator to simulate the immune system. Then, the dimension-reduced type generalized additive model (GAM is employed to train a statistical regression model by using the input and output data of ABM and play a role as an emulator during history matching. Next, we reduce the input space of parameters by introducing an implausible measure to discard the implausible input values. At last, the estimation of model parameters is obtained using the particle swarm optimization algorithm (PSO by fitting the experiment data among the non-implausible input values. The real Influeza A Virus (IAV data set is employed to demonstrate the performance of our proposed method, and the results show that the proposed method not only has good fitting and predicting accuracy, but it also owns favorable computational efficiency.
Covariant diagrams for one-loop matching
Energy Technology Data Exchange (ETDEWEB)
Zhang, Zhengkang [Michigan Univ., Ann Arbor, MI (United States). Michigan Center for Theoretical Physics; Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)
2016-10-15
We present a diagrammatic formulation of recently-revived covariant functional approaches to one-loop matching from an ultraviolet (UV) theory to a low-energy effective field theory. Various terms following from a covariant derivative expansion (CDE) are represented by diagrams which, unlike conventional Feynman diagrams, involve gaugecovariant quantities and are thus dubbed ''covariant diagrams.'' The use of covariant diagrams helps organize and simplify one-loop matching calculations, which we illustrate with examples. Of particular interest is the derivation of UV model-independent universal results, which reduce matching calculations of specific UV models to applications of master formulas. We show how such derivation can be done in a more concise manner than the previous literature, and discuss how additional structures that are not directly captured by existing universal results, including mixed heavy-light loops, open covariant derivatives, and mixed statistics, can be easily accounted for.
10 CFR 609.16 - Perfection of liens and preservation of collateral.
2010-01-01
... 10 Energy 4 2010-01-01 2010-01-01 false Perfection of liens and preservation of collateral. 609.16... THAT EMPLOY INNOVATIVE TECHNOLOGIES § 609.16 Perfection of liens and preservation of collateral. (a... to perfect and maintain liens, as applicable, on assets which are pledged as collateral for the...
Digital health revolution: perfect storm or perfect opportunity for pharmaceutical R&D?
Hird, Nick; Ghosh, Samik; Kitano, Hiroaki
2016-06-01
The convergence of technology and medicine has pushed healthcare to the brink of a major disruption that pharma has, until recently, been slow to recognize. Tech players have pioneered the emerging field of digital wellness and health, and pharma is ideally placed to use its expertise in drug development and embrace these technologies to create digital applications that address major medical needs. This review describes digital innovation from a pharma R&D perspective, outlining principal drivers, digital components, opportunities and challenges as well as a sustainable new business model predicated on empowered patients and achieving therapeutic outcomes. Copyright © 2016 Elsevier Ltd. All rights reserved.
Matching theory for wireless networks
Han, Zhu; Saad, Walid
2017-01-01
This book provides the fundamental knowledge of the classical matching theory problems. It builds up the bridge between the matching theory and the 5G wireless communication resource allocation problems. The potentials and challenges of implementing the semi-distributive matching theory framework into the wireless resource allocations are analyzed both theoretically and through implementation examples. Academics, researchers, engineers, and so on, who are interested in efficient distributive wireless resource allocation solutions, will find this book to be an exceptional resource. .
Perfect Undetectable Acoustic Device from Fabry-Pérot Resonances
Chen, Huanyang; Zhou, Yangyang; Zhou, Mengying; Xu, Lin; Liu, Qing Huo
2018-02-01
Transformation acoustics is a method to design novel acoustic devices, while the complexity of the material parameters hinders its progress. In this paper, we analytically present a three-dimensional perfect undetectable acoustic device from Fabry-Pérot resonances and confirm its functionality from Mie theory. Such a mechanism goes beyond the traditional transformation acoustics. In addition, such a reduced version can be realized by holey-structured metamaterials. Our theory paves a way to the implementation of three-dimensional transformation acoustic devices.
The Hamiltonian structure of general relativistic perfect fluids
International Nuclear Information System (INIS)
Bao, D.; Houston Univ., TX; Marsden, J.; Walton, R.
1985-01-01
We show that the evolution equations for a perfect fluid coupled to general relativity in a general lapse and shift, are Hamiltonian relative to a certain Poisson structure. For the fluid variables, a Lie-Poisson structure associated to the dual of a semi-direct product Lie algebra is used, while the bracket for the gravitational variables has the usual canonical symplectic structure. The evolution is governed by a Hamiltonian which is equivalent to that obtained from a canonical analysis. The relationship of our Hamiltonian structure with other approaches in the literature, such as Clebsch potentials, Lagrangian to Eulerian transformations, and its use in clarifying linearization stability, are discussed. (orig.)
Extinction in finite perfect crystals: Case of a sphere
International Nuclear Information System (INIS)
Al Haddad, M.; Becker, P.
1990-01-01
The extinction factor in finite perfect crystals is calculated from pure dynamical theory. In particular, a detailed solution is proposed for a sphere, in which case the extinction factor depends on the Bragg angle θ and the parameter (R/Λ), where R is the radius of the crystal and Λ the extinction length. An approximate solution based on the Laue geometry is proposed and corrections to take care of the complex boundary conditions are presented. An expression easily usable in refinement programs is proposed that fits the exact value to better than 1%. (orig.)