WorldWideScience

Sample records for minimizing oseen-frank energy

  1. Minimizers of the Landau-de Gennes Energy Around a Spherical Colloid Particle

    Science.gov (United States)

    Alama, Stan; Bronsard, Lia; Lamy, Xavier

    2016-10-01

    We consider energy minimizing configurations of a nematic liquid crystal around a spherical colloid particle, in the context of the Landau-de Gennes model. The nematic is assumed to occupy the exterior of a ball B r0, and satisfy homeotropic weak anchoring at the surface of the colloid and approach a uniform uniaxial state as {|x|to∞}. We study the minimizers in two different limiting regimes: for balls which are small {r_0≪ L^{1/2}} compared to the characteristic length scale {L^{1/2}}, and for large balls, {r_0≫ L^{1/2}}. The relationship between the radius and the anchoring strength W is also relevant. For small balls we obtain a limiting quadrupolar configuration, with a "Saturn ring" defect for relatively strong anchoring, corresponding to an exchange of eigenvalues of the Q-tensor. In the limit of very large balls we obtain an axisymmetric minimizer of the Oseen-Frank energy, and a dipole configuration with exactly one point defect is obtained.

  2. Determining Knots by Minimizing Energy

    Institute of Scientific and Technical Information of China (English)

    Cai-Ming Zhang; Hui-Jian Han; Fuhua Frank Cheng

    2006-01-01

    A new method for determining knots to construct polynomial curves is presented. At each data point, a quadric curve which passes three consecutive points is constructed. The knots for constructing the quadric curve are determined by minimizing the internal strain energy, which can be regarded as a function of the angle. The function of the angle is expanded as a Taylor series with two terms, then the two knot intervals between the three consecutive points are defined by linear expression. Between the two consecutive points, there are two knot intervals, and the combination of the two knot intervals is used to define the final knot interval. A comparison of the new method with several existing methods is included.

  3. Landau–De Gennes Theory of Nematic Liquid Crystals: the Oseen–Frank Limit and Beyond

    KAUST Repository

    Majumdar, Apala

    2009-07-07

    We study global minimizers of a continuum Landau-De Gennes energy functional for nematic liquid crystals, in three-dimensional domains, subject to uniaxial boundary conditions. We analyze the physically relevant limit of small elastic constant and show that global minimizers converge strongly, in W1,2, to a global minimizer predicted by the Oseen-Frank theory for uniaxial nematic liquid crystals with constant order parameter. Moreover, the convergence is uniform in the interior of the domain, away from the singularities of the limiting Oseen-Frank global minimizer. We obtain results on the rate of convergence of the eigenvalues and the regularity of the eigenvectors of the Landau-De Gennes global minimizer. We also study the interplay between biaxiality and uniaxiality in Landau-De Gennes global energy minimizers and obtain estimates for various related quantities such as the biaxiality parameter and the size of admissible strongly biaxial regions. © Springer-Verlag (2009).

  4. Linear embedding of free energy minimization

    CERN Document Server

    Moussa, Jonathan E

    2016-01-01

    Exact free energy minimization is a convex optimization problem that is usually approximated with stochastic sampling methods. Deterministic approximations have been less successful because many desirable properties have been difficult to attain. Such properties include the preservation of convexity, lower bounds on free energy, and applicability to systems without subsystem structure. We satisfy all of these properties by embedding free energy minimization into a linear program over energy-resolved expectation values. Numerical results on small systems are encouraging, but a lack of size consistency necessitates further development for large systems.

  5. Utility Constrained Energy Minimization In Aloha Networks

    CERN Document Server

    Khodaian, Amir Mahdi; Talebi, Mohammad S

    2010-01-01

    In this paper we consider the issue of energy efficiency in random access networks and show that optimizing transmission probabilities of nodes can enhance network performance in terms of energy consumption and fairness. First, we propose a heuristic power control method that improves throughput, and then we model the Utility Constrained Energy Minimization (UCEM) problem in which the utility constraint takes into account single and multi node performance. UCEM is modeled as a convex optimization problem and Sequential Quadratic Programming (SQP) is used to find optimal transmission probabilities. Numerical results show that our method can achieve fairness, reduce energy consumption and enhance lifetime of such networks.

  6. Measurable Maximal Energy and Minimal Time Interval

    CERN Document Server

    Dahab, Eiman Abou El

    2014-01-01

    The possibility of finding the measurable maximal energy and the minimal time interval is discussed in different quantum aspects. It is found that the linear generalized uncertainty principle (GUP) approach gives a non-physical result. Based on large scale Schwarzshild solution, the quadratic GUP approach is utilized. The calculations are performed at the shortest distance, at which the general relativity is assumed to be a good approximation for the quantum gravity and at larger distances, as well. It is found that both maximal energy and minimal time have the order of the Planck time. Then, the uncertainties in both quantities are accordingly bounded. Some physical insights are addressed. Also, the implications on the physics of early Universe and on quantized mass are outlined. The results are related to the existence of finite cosmological constant and minimum mass (mass quanta).

  7. Smooth GERBS, orthogonal systems and energy minimization

    Science.gov (United States)

    Dechevsky, Lubomir T.; Zanaty, Peter

    2013-12-01

    New results are obtained in three mutually related directions of the rapidly developing theory of generalized expo-rational B-splines (GERBS) [7, 6]: closed-form computability of C∞-smooth GERBS in terms of elementary and special functions, Hermite interpolation and least-squares best approximation via smooth GERBS, energy minimizing properties of smooth GERBS similar to those of the classical cubic polynomial B-splines.

  8. Wormholes minimally violating the null energy condition

    CERN Document Server

    Bouhmadi-Lopez, Mariam; Martin-Moruno, Prado

    2014-01-01

    We consider novel wormhole solutions supported by a matter content that minimally violates the null energy condition. More specifically, we consider an equation of state in which the sum of the energy density and radial pressure is proportional to a constant with a value smaller than that of the inverse area characterising the system, i.e., the area of the wormhole mouth. This approach is motivated by a recently proposed cosmological event, denoted "the little sibling of the big rip", where the Hubble rate and the scale factor blow up but the cosmic derivative of the Hubble rate does not [1]. By using the cut-and-paste approach, we match interior spherically symmetric wormhole solutions to an exterior Schwarzschild geometry, and analyze the stability of the thin-shell to linearized spherically symmetric perturbations around static solutions, by choosing suitable properties for the exotic material residing on the junction interface radius. Furthermore, we also consider an inhomogeneous generalisation of the eq...

  9. Simulating granular materials by energy minimization

    Science.gov (United States)

    Krijgsman, D.; Luding, S.

    2016-11-01

    Discrete element methods are extremely helpful in understanding the complex behaviors of granular media, as they give valuable insight into all internal variables of the system. In this paper, a novel discrete element method for performing simulations of granular media is presented, based on the minimization of the potential energy in the system. Contrary to most discrete element methods (i.e., soft-particle method, event-driven method, and non-smooth contact dynamics), the system does not evolve by (approximately) integrating Newtons equations of motion in time, but rather by searching for mechanical equilibrium solutions for the positions of all particles in the system, which is mathematically equivalent to locally minimizing the potential energy. The new method allows for the rapid creation of jammed initial conditions (to be used for further studies) and for the simulation of quasi-static deformation problems. The major advantage of the new method is that it allows for truly static deformations. The system does not evolve with time, but rather with the externally applied strain or load, so that there is no kinetic energy in the system, in contrast to other quasi-static methods. The performance of the algorithm for both types of applications of the method is tested. Therefore we look at the required number of iterations, for the system to converge to a stable solution. For each single iteration, the required computational effort scales linearly with the number of particles. During the process of creating initial conditions, the required number of iterations for two-dimensional systems scales with the square root of the number of particles in the system. The required number of iterations increases for systems closer to the jamming packing fraction. For a quasi-static pure shear deformation simulation, the results of the new method are validated by regular soft-particle dynamics simulations. The energy minimization algorithm is able to capture the evolution of the

  10. Microgrids: Energy management by loss minimization technique

    Directory of Open Access Journals (Sweden)

    A. K. Basu, S. Chowdhury, S.P. Chowdhury

    2011-03-01

    Full Text Available Energy management is a techno-economic issue, which dictates, in the context of microgrids, how optimal investment in technology front could bring optimal power quality and reliability (PQR of supply to the consumers. Investment in distributed energy resources (DERs, with their connection to the utility grid at optimal locations and with optimal sizes, saves energy in the form of line loss reduction. Line loss reduction is the indirect benefit to the microgrid owner who may recover it as an incentive from utility. The present paper focuses on planning of optimal siting and sizing of DERs based on minimization of line loss. Optimal siting is done, here, on the loss sensitivity index (LSI method and optimal sizing by differential evolution (DE algorithms, which is, again, compared with particle swarm optimization (PSO technique. Studies are conducted on 6-bus and 14-bus radial networks under islanded mode of operation with electric demand profile. Islanding helps planning of DER capacity of microgrid, which is self-sufficient to cater its own consumers without utility’s support.

  11. Wormholes minimally violating the null energy condition

    Science.gov (United States)

    Bouhmadi-López, Mariam; Lobo, Francisco S. N.; Martín-Moruno, Prado

    2014-11-01

    We consider novel wormhole solutions supported by a matter content that minimally violates the null energy condition. More specifically, we consider an equation of state in which the sum of the energy density and radial pressure is proportional to a constant with a value smaller than that of the inverse area characterising the system, i.e., the area of the wormhole mouth. This approach is motivated by a recently proposed cosmological event, denoted "the little sibling of the big rip", where the Hubble rate and the scale factor blow up but the cosmic derivative of the Hubble rate does not [1]. By using the cut-and-paste approach, we match interior spherically symmetric wormhole solutions to an exterior Schwarzschild geometry, and analyse the stability of the thin-shell to linearized spherically symmetric perturbations around static solutions, by choosing suitable properties for the exotic material residing on the junction interface radius. Furthermore, we also consider an inhomogeneous generalization of the equation of state considered above and analyse the respective stability regions. In particular, we obtain a specific wormhole solution with an asymptotic behaviour corresponding to a global monopole.

  12. Wormholes minimally violating the null energy condition

    Energy Technology Data Exchange (ETDEWEB)

    Bouhmadi-López, Mariam [Departamento de Física, Universidade da Beira Interior, 6200 Covilhã (Portugal); Lobo, Francisco S N; Martín-Moruno, Prado, E-mail: mariam.bouhmadi@ehu.es, E-mail: fslobo@fc.ul.pt, E-mail: pmmoruno@fc.ul.pt [Centro de Astronomia e Astrofísica da Universidade de Lisboa, Campo Grande, Edifício C8, 1749-016 Lisboa (Portugal)

    2014-11-01

    We consider novel wormhole solutions supported by a matter content that minimally violates the null energy condition. More specifically, we consider an equation of state in which the sum of the energy density and radial pressure is proportional to a constant with a value smaller than that of the inverse area characterising the system, i.e., the area of the wormhole mouth. This approach is motivated by a recently proposed cosmological event, denoted {sup t}he little sibling of the big rip{sup ,} where the Hubble rate and the scale factor blow up but the cosmic derivative of the Hubble rate does not [1]. By using the cut-and-paste approach, we match interior spherically symmetric wormhole solutions to an exterior Schwarzschild geometry, and analyse the stability of the thin-shell to linearized spherically symmetric perturbations around static solutions, by choosing suitable properties for the exotic material residing on the junction interface radius. Furthermore, we also consider an inhomogeneous generalization of the equation of state considered above and analyse the respective stability regions. In particular, we obtain a specific wormhole solution with an asymptotic behaviour corresponding to a global monopole.

  13. 3D motion analysis via energy minimization

    Energy Technology Data Exchange (ETDEWEB)

    Wedel, Andreas

    2009-10-16

    This work deals with 3D motion analysis from stereo image sequences for driver assistance systems. It consists of two parts: the estimation of motion from the image data and the segmentation of moving objects in the input images. The content can be summarized with the technical term machine visual kinesthesia, the sensation or perception and cognition of motion. In the first three chapters, the importance of motion information is discussed for driver assistance systems, for machine vision in general, and for the estimation of ego motion. The next two chapters delineate on motion perception, analyzing the apparent movement of pixels in image sequences for both a monocular and binocular camera setup. Then, the obtained motion information is used to segment moving objects in the input video. Thus, one can clearly identify the thread from analyzing the input images to describing the input images by means of stationary and moving objects. Finally, I present possibilities for future applications based on the contents of this thesis. Previous work in each case is presented in the respective chapters. Although the overarching issue of motion estimation from image sequences is related to practice, there is nothing as practical as a good theory (Kurt Lewin). Several problems in computer vision are formulated as intricate energy minimization problems. In this thesis, motion analysis in image sequences is thoroughly investigated, showing that splitting an original complex problem into simplified sub-problems yields improved accuracy, increased robustness, and a clear and accessible approach to state-of-the-art motion estimation techniques. In Chapter 4, optical flow is considered. Optical flow is commonly estimated by minimizing the combined energy, consisting of a data term and a smoothness term. These two parts are decoupled, yielding a novel and iterative approach to optical flow. The derived Refinement Optical Flow framework is a clear and straight-forward approach to

  14. Dimensionality of Local Minimizers of the Interaction Energy

    KAUST Repository

    Balagué, D.

    2013-05-22

    In this work we consider local minimizers (in the topology of transport distances) of the interaction energy associated with a repulsive-attractive potential. We show how the dimensionality of the support of local minimizers is related to the repulsive strength of the potential at the origin. © 2013 Springer-Verlag Berlin Heidelberg.

  15. Energy minimization for the flow in ducts and networks

    CERN Document Server

    Sochi, Taha

    2014-01-01

    The present paper is an attempt to demonstrate how the energy minimization principle may be considered as a governing rule for the physical equilibrium that determines the flow fields in tubes and networks. We previously investigated this issue using a numerical stochastic method, specifically simulated annealing, where we demonstrated the problem by some illuminating examples and concluded that energy minimization principle can be a valid hypothesis. The investigation in this paper is more general as it is based to a certain extent on an analytical approach.

  16. Ideal, best packing, and energy minimizing double helices

    CERN Document Server

    O'Hara, Jun

    2011-01-01

    We study optimal double helices with straight axes (or the fattest tubes around them) computationally using three kinds of functionals; ideal ones using ropelength, best volume packing ones, and energy minimizers using two one-parameter families of interaction energies between two strands of types $r^{-\\alpha}$ and $\\frac1r\\exp(-kr)$. We compare the numerical results with experimental data of DNA.

  17. Comments on the Energy Principle and the Minimizing Eigenfunction

    Science.gov (United States)

    Schnack, Dalton D.

    In this lecture, we make some comments on the MHD energy principle and the process of minimization. These remarks are quite general. Some of them require a considerable amount of vector algebra and integration by parts. Most of these details have been omitted for clarity of presentation.

  18. Minimalism

    CERN Document Server

    Obendorf, Hartmut

    2009-01-01

    The notion of Minimalism is proposed as a theoretical tool supporting a more differentiated understanding of reduction and thus forms a standpoint that allows definition of aspects of simplicity. This book traces the development of minimalism, defines the four types of minimalism in interaction design, and looks at how to apply it.

  19. Minimal Self-Models and the Free Energy Principle

    Directory of Open Access Journals (Sweden)

    Jakub eLimanowski

    2013-09-01

    Full Text Available The term "minimal phenomenal selfhood" describes the basic, pre-reflective experience of being a self (Blanke & Metzinger, 2009. Theoretical accounts of the minimal self have long recognized the importance and the ambivalence of the body as both part of the physical world, and the enabling condition for being in this world (Gallagher, 2005; Grafton, 2009. A recent account of minimal phenomenal selfhood (MPS, Metzinger, 2004a centers on the consideration that minimal selfhood emerges as the result of basic self-modeling mechanisms, thereby being founded on pre-reflective bodily processes. The free energy principle (FEP, Friston, 2010 is a novel unified theory of cortical function that builds upon the imperative that self-organizing systems entail hierarchical generative models of the causes of their sensory input, which are optimized by minimizing free energy as an approximation of the log-likelihood of the model. The implementation of the FEP via predictive coding mechanisms and in particular the active inference principle emphasizes the role of embodiment for predictive self-modeling, which has been appreciated in recent publications. In this review, we provide an overview of these conceptions and illustrate thereby the potential power of the FEP in explaining the mechanisms underlying minimal selfhood and its key constituents, multisensory integration, interoception, agency, perspective, and the experience of mineness. We conclude that the conceptualization of MPS can be well mapped onto a hierarchical generative model furnished by the free energy principle and may constitute the basis for higher-level, cognitive forms of self-referral, as well as the understanding of other minds.

  20. Minimizing Energy Spread In The REX/HIE-ISOLDE Linac

    CERN Document Server

    Yucemoz, Mert

    2017-01-01

    This report tries to minimize the energy spread of the beam at the end of the REX-HIE-ISOLDE Linac using the last RF cavity as a buncher. Beams with very low energy spread are often required by the users of the facility In addition, one of the main reason to have minimum energy spread in longitudinal phase space is that higher beam energy spread translates in to a position spread after interacting with target. This causes an overlap in the position of different particles that makes it difficult to distinguish them. Hence, in order to find the operation settings for minimum energy spread at the end of the REX-HIE-ISOLDE linac and to inspect the ongoing physics, several functions on Matlab were created that runs beam dynamics program called “TRACKV39” that provides some graphs and values as a result for analysis.

  1. Strain energy minimization in SSC (Superconducting Super Collider) magnet winding

    Energy Technology Data Exchange (ETDEWEB)

    Cook, J.M.

    1990-09-24

    Differential geometry provides a natural family of coordinate systems, the Frenet frame, in which to specify the geometric properties of magnet winding. By a modification of the Euler-Bernoulli thin rod model, the strain energy is defined with respect to this frame. Then it is minimized by a direct method from the calculus of variations. The mathematics, its implementation in a computer program, and some analysis of an SSC dipole by the program will be described. 16 refs.

  2. On minimal energy dipole moment distributions in regular polygonal agglomerates

    Science.gov (United States)

    Rosa, Adriano Possebon; Cunha, Francisco Ricardo; Ceniceros, Hector Daniel

    2017-01-01

    Static, regular polygonal and close-packed clusters of spherical magnetic particles and their energy-minimizing magnetic moments are investigated in a two-dimensional setting. This study focuses on a simple particle system which is solely described by the dipole-dipole interaction energy, both without and in the presence of an in-plane magnetic field. For a regular polygonal structure of n sides with n ≥ 3 , and in the absence of an external field, it is proved rigorously that the magnetic moments given by the roots of unity, i.e. tangential to the polygon, are a minimizer of the dipole-dipole interaction energy. Also, for zero external field, new multiple local minima are discovered for the regular polygonal agglomerates. The number of found local extrema is proportional to [ n / 2 ] and these critical points are characterized by the presence of a pair of magnetic moments with a large deviation from the tangential configuration and whose particles are at least three diameters apart. The changes induced by an in-plane external magnetic field on the minimal energy, tangential configurations are investigated numerically. The two critical fields, which correspond to a crossover with the linear chain minimal energy and with the break-up of the agglomerate, respectively are examined in detail. In particular, the numerical results are compared directly with the asymptotic formulas of Danilov et al. (2012) [23] and a remarkable agreement is found even for moderate to large fields. Finally, three examples of close-packed structures are investigated: a triangle, a centered hexagon, and a 19-particle close packed cluster. The numerical study reveals novel, illuminating characteristics of these compact clusters often seen in ferrofluids. The centered hexagon is energetically favorable to the regular hexagon and the minimal energy for the larger 19-particle cluster is even lower than that of the close packed hexagon. In addition, this larger close packed agglomerate has two

  3. Scheduling to Minimize Energy and Flow Time in Broadcast Scheduling

    CERN Document Server

    Moseley, Benjamin

    2010-01-01

    In this paper we initiate the study of minimizing power consumption in the broadcast scheduling model. In this setting there is a wireless transmitter. Over time requests arrive at the transmitter for pages of information. Multiple requests may be for the same page. When a page is transmitted, all requests for that page receive the transmission simulteneously. The speed the transmitter sends data at can be dynamically scaled to conserve energy. We consider the problem of minimizing flow time plus energy, the most popular scheduling metric considered in the standard scheduling model when the scheduler is energy aware. We will assume that the power consumed is modeled by an arbitrary convex function. For this problem there is a $\\Omega(n)$ lower bound. Due to the lower bound, we consider the resource augmentation model of Gupta \\etal \\cite{GuptaKP10}. Using resource augmentation, we give a scalable algorithm. Our result also gives a scalable non-clairvoyant algorithm for minimizing weighted flow time plus energ...

  4. Cooperative relay-based multicasting for energy and delay minimization

    KAUST Repository

    Atat, Rachad

    2012-08-01

    Relay-based multicasting for the purpose of cooperative content distribution is studied. Optimized relay selection is performed with the objective of minimizing the energy consumption or the content distribution delay within a cluster of cooperating mobiles. Two schemes are investigated. The first consists of the BS sending the data only to the relay, and the second scheme considers the scenario of threshold-based multicasting by the BS, where a relay is selected to transmit the data to the mobiles that were not able to receive the multicast data. Both schemes show significant superiority compared to the non-cooperative scenarios, in terms of energy consumption and delay reduction. © 2012 IEEE.

  5. Chemical process simulation for minimizing energy consumption in pulp mills

    Energy Technology Data Exchange (ETDEWEB)

    Cardoso, Marcelo; Oliveira, Katia Dionisio de; Costa, George Alberto Avelar [Department of Chemical Engineering/School of Engineering, Federal University of Minas Gerais (UFMG), Belo Horizonte/MG (Brazil); Passos, Maria Laura [Collaborator Researcher, Drying Center, Chemical Engineering Department, Federal University of Sao Carlos (UFSCar) (Brazil)

    2009-01-15

    Chemical process simulation has proven to be an effective tool for performing a systematic and global analysis of energy systems to identify routes for maximizing the process efficiency concerning to the heat recovery. This paper shows an application of computer simulations in a Brazilian pulp mill, using two strategies for minimizing the mill energy consumption. In the first one, the overall heat transfer coefficient has been predicted for each body of the multiple effect evaporators by using continuous on-line data from the industrial plant in the black liquor recover unit. By monitoring oscillations of this heat transfer coefficient, the suitable time for washing the evaporator heat transfer surfaces can be well determined, reducing the energy loss during black liquor evaporation. In the second strategy, the liquor combustion has been simulated as function of the black liquor solids concentration to analyze its effect on the recovery boiler efficiency improvement. (author)

  6. AMG by element agglomeration and constrained energy minimization interpolation

    Energy Technology Data Exchange (ETDEWEB)

    Kolev, T V; Vassilevski, P S

    2006-02-17

    This paper studies AMG (algebraic multigrid) methods that utilize energy minimization construction of the interpolation matrices locally, in the setting of element agglomeration AMG. The coarsening in element agglomeration AMG is done by agglomerating fine-grid elements, with coarse element matrices defined by a local Galerkin procedure applied to the matrix assembled from the individual fine-grid element matrices. This local Galerkin procedure involves only the coarse basis restricted to the agglomerated element. To construct the coarse basis, one exploits previously proposed constraint energy minimization procedures now applied to the local matrix. The constraints are that a given set of vectors should be interpolated exactly, not only globally, but also locally on every agglomerated element. The paper provides algorithmic details, as well as a convergence result based on a ''local-to-global'' energy bound of the resulting multiple-vector fitting AMG interpolation mappings. A particular implementation of the method is illustrated with a set of numerical experiments.

  7. A strategy to find minimal energy nanocluster structures.

    Science.gov (United States)

    Rogan, José; Varas, Alejandro; Valdivia, Juan Alejandro; Kiwi, Miguel

    2013-11-05

    An unbiased strategy to search for the global and local minimal energy structures of free standing nanoclusters is presented. Our objectives are twofold: to find a diverse set of low lying local minima, as well as the global minimum. To do so, we use massively the fast inertial relaxation engine algorithm as an efficient local minimizer. This procedure turns out to be quite efficient to reach the global minimum, and also most of the local minima. We test the method with the Lennard-Jones (LJ) potential, for which an abundant literature does exist, and obtain novel results, which include a new local minimum for LJ13 , 10 new local minima for LJ14 , and thousands of new local minima for 15≤N≤65. Insights on how to choose the initial configurations, analyzing the effectiveness of the method in reaching low-energy structures, including the global minimum, are developed as a function of the number of atoms of the cluster. Also, a novel characterization of the potential energy surface, analyzing properties of the local minima basins, is provided. The procedure constitutes a promising tool to generate a diverse set of cluster conformations, both two- and three-dimensional, that can be used as an input for refinement by means of ab initio methods. Copyright © 2013 Wiley Periodicals, Inc.

  8. Energy Cost Minimization in Heterogeneous Cellular Networks with Hybrid Energy Supplies

    Directory of Open Access Journals (Sweden)

    Bang Wang

    2016-01-01

    Full Text Available The ever increasing data demand has led to the significant increase of energy consumption in cellular mobile networks. Recent advancements in heterogeneous cellular networks and green energy supplied base stations provide promising solutions for cellular communications industry. In this article, we first review the motivations and challenges as well as approaches to address the energy cost minimization problem for such green heterogeneous networks. Owing to the diversities of mobile traffic and renewable energy, the energy cost minimization problem involves both temporal and spatial optimization of resource allocation. We next present a new solution to illustrate how to combine the optimization of the temporal green energy allocation and spatial mobile traffic distribution. The whole optimization problem is decomposed into four subproblems, and correspondingly our proposed solution is divided into four parts: energy consumption estimation, green energy allocation, user association, and green energy reallocation. Simulation results demonstrate that our proposed algorithm can significantly reduce the total energy cost.

  9. Outage Probability Minimization for Energy Harvesting Cognitive Radio Sensor Networks

    Directory of Open Access Journals (Sweden)

    Fan Zhang

    2017-01-01

    Full Text Available The incorporation of cognitive radio (CR capability in wireless sensor networks yields a promising network paradigm known as CR sensor networks (CRSNs, which is able to provide spectrum efficient data communication. However, due to the high energy consumption results from spectrum sensing, as well as subsequent data transmission, the energy supply for the conventional sensor nodes powered by batteries is regarded as a severe bottleneck for sustainable operation. The energy harvesting technique, which gathers energy from the ambient environment, is regarded as a promising solution to perpetually power-up energy-limited devices with a continual source of energy. Therefore, applying the energy harvesting (EH technique in CRSNs is able to facilitate the self-sustainability of the energy-limited sensors. The primary concern of this study is to design sensing-transmission policies to minimize the long-term outage probability of EH-powered CR sensor nodes. We formulate this problem as an infinite-horizon discounted Markov decision process and propose an ϵ-optimal sensing-transmission (ST policy through using the value iteration algorithm. ϵ is the error bound between the ST policy and the optimal policy, which can be pre-defined according to the actual need. Moreover, for a special case that the signal-to-noise (SNR power ratio is sufficiently high, we present an efficient transmission (ET policy and prove that the ET policy achieves the same performance with the ST policy. Finally, extensive simulations are conducted to evaluate the performance of the proposed policies and the impaction of various network parameters.

  10. Outage Probability Minimization for Energy Harvesting Cognitive Radio Sensor Networks.

    Science.gov (United States)

    Zhang, Fan; Jing, Tao; Huo, Yan; Jiang, Kaiwei

    2017-01-24

    The incorporation of cognitive radio (CR) capability in wireless sensor networks yields a promising network paradigm known as CR sensor networks (CRSNs), which is able to provide spectrum efficient data communication. However, due to the high energy consumption results from spectrum sensing, as well as subsequent data transmission, the energy supply for the conventional sensor nodes powered by batteries is regarded as a severe bottleneck for sustainable operation. The energy harvesting technique, which gathers energy from the ambient environment, is regarded as a promising solution to perpetually power-up energy-limited devices with a continual source of energy. Therefore, applying the energy harvesting (EH) technique in CRSNs is able to facilitate the self-sustainability of the energy-limited sensors. The primary concern of this study is to design sensing-transmission policies to minimize the long-term outage probability of EH-powered CR sensor nodes. We formulate this problem as an infinite-horizon discounted Markov decision process and propose an ϵ-optimal sensing-transmission (ST) policy through using the value iteration algorithm. ϵ is the error bound between the ST policy and the optimal policy, which can be pre-defined according to the actual need. Moreover, for a special case that the signal-to-noise (SNR) power ratio is sufficiently high, we present an efficient transmission (ET) policy and prove that the ET policy achieves the same performance with the ST policy. Finally, extensive simulations are conducted to evaluate the performance of the proposed policies and the impaction of various network parameters.

  11. Inference with minimal Gibbs free energy in information field theory.

    Science.gov (United States)

    Ensslin, Torsten A; Weig, Cornelius

    2010-11-01

    Non-linear and non-gaussian signal inference problems are difficult to tackle. Renormalization techniques permit us to construct good estimators for the posterior signal mean within information field theory (IFT), but the approximations and assumptions made are not very obvious. Here we introduce the simple concept of minimal Gibbs free energy to IFT, and show that previous renormalization results emerge naturally. They can be understood as being the gaussian approximation to the full posterior probability, which has maximal cross information with it. We derive optimized estimators for three applications, to illustrate the usage of the framework: (i) reconstruction of a log-normal signal from poissonian data with background counts and point spread function, as it is needed for gamma ray astronomy and for cosmography using photometric galaxy redshifts, (ii) inference of a gaussian signal with unknown spectrum, and (iii) inference of a poissonian log-normal signal with unknown spectrum, the combination of (i) and (ii). Finally we explain how gaussian knowledge states constructed by the minimal Gibbs free energy principle at different temperatures can be combined into a more accurate surrogate of the non-gaussian posterior.

  12. Interactive seismic interpretation with piecewise global energy minimization

    KAUST Repository

    Hollt, Thomas

    2011-03-01

    Increasing demands in world-wide energy consumption and oil depletion of large reservoirs have resulted in the need for exploring smaller and more complex oil reservoirs. Planning of the reservoir valorization usually starts with creating a model of the subsurface structures, including seismic faults and horizons. However, seismic interpretation and horizon tracing is a difficult and error-prone task, often resulting in hours of work needing to be manually repeated. In this paper, we propose a novel, interactive workflow for horizon interpretation based on well positions, which include additional geological and geophysical data captured by actual drillings. Instead of interpreting the volume slice-by-slice in 2D, we propose 3D seismic interpretation based on well positions. We introduce a combination of 2D and 3D minimal cost path and minimal cost surface tracing for extracting horizons with very little user input. By processing the volume based on well positions rather than slice-based, we are able to create a piecewise optimal horizon surface at interactive rates. We have integrated our system into a visual analysis platform which supports multiple linked views for fast verification, exploration and analysis of the extracted horizons. The system is currently being evaluated by our collaborating domain experts. © 2011 IEEE.

  13. Energy minimization strategies and renewable energy utilization for desalination: a review.

    Science.gov (United States)

    Subramani, Arun; Badruzzaman, Mohammad; Oppenheimer, Joan; Jacangelo, Joseph G

    2011-02-01

    Energy is a significant cost in the economics of desalinating waters, but water scarcity is driving the rapid expansion in global installed capacity of desalination facilities. Conventional fossil fuels have been utilized as their main energy source, but recent concerns over greenhouse gas (GHG) emissions have promoted global development and implementation of energy minimization strategies and cleaner energy supplies. In this paper, a comprehensive review of energy minimization strategies for membrane-based desalination processes and utilization of lower GHG emission renewable energy resources is presented. The review covers the utilization of energy efficient design, high efficiency pumping, energy recovery devices, advanced membrane materials (nanocomposite, nanotube, and biomimetic), innovative technologies (forward osmosis, ion concentration polarization, and capacitive deionization), and renewable energy resources (solar, wind, and geothermal). Utilization of energy efficient design combined with high efficiency pumping and energy recovery devices have proven effective in full-scale applications. Integration of advanced membrane materials and innovative technologies for desalination show promise but lack long-term operational data. Implementation of renewable energy resources depends upon geography-specific abundance, a feasible means of handling renewable energy power intermittency, and solving technological and economic scale-up and permitting issues.

  14. Energy minimization calculations for diamond (111) surface reconstructions

    Energy Technology Data Exchange (ETDEWEB)

    Vanderbilt, D.; Louie, S.G.

    1984-08-01

    A remarkable variety of surface reconstructions occur on the (111) surfaces of the tetrahedral elements C, Si and Ge. A possible common denominator may be the occurrence of a similar 2 x 1 reconstruction on all three elemental surfaces. While clear 2 x 1 LEED patterns are observed for Si and Ge (111) surfaces, LEED cannot distinguish between a true 2 x 2 or disordered domains of 2 x 1 for the diamond (111) surface. However, the similarity of the angle-resolved photoemission (ARUPS) results for C, Si, and Ge suggests that a common 2 x 1 structure may be responsible. The 2 x 1 structure disappears upon annealing for Si and Ge but appears upon annealing for C, indicating that it may be thermodynamically stable only for C. Thus the study of the diamond 2 x 2/2 x 1 surface is of particular interest. Here, we report direct energy minimization calculations for these models. A first principles linear combination of atomic orbitals approach has been used to calculate total energies in the pseudopotential and local density (LDA) approximations. 27 refs., 3 figs., 2 tabs.

  15. Shape minimization of the dissipated energy in dyadic trees

    CERN Document Server

    De La Sablonière, Xavier Dubois; Privat, Yannick

    2010-01-01

    In this paper, we study the role of boundary conditions on the optimal shape of a dyadic tree in which flows a Newtonian fluid. Our optimization problem consists in finding the shape of the tree that minimizes the viscous energy dissipated by the fluid with a constrained volume, under the assumption that the total flow of the fluid is conserved throughout the structure. These hypotheses model situations where a fluid is transported from a source towards a 3D domain into which the transport network also spans. Such situations could be encountered in organs like for instance the lungs and the vascular networks. Two fluid regimes are studied: (i) low flow regime (Poiseuille) in trees with an arbitrary number of generations using a matricial approach and (ii) non linear flow regime (Navier-Stokes, moderate regime with a Reynolds number $100$) in trees of two generations using shape derivatives in an augmented Lagrangian algorithm coupled with a 2D/3D finite elements code to solve Navier-Stokes equations. It relie...

  16. Free-energy Minimization and The Dark Room Problem

    Directory of Open Access Journals (Sweden)

    Karl eFriston

    2012-05-01

    Full Text Available Recent years have seen the emergence of an important new fundamental theory of brain function. This theory brings information-theoretic, Bayesian, neuroscientific, and machine learning approaches into a single framework whose overarching principle is the minimization of surprise (or, equivalently, the maximization of expectation. The most comprehensive such treatment is the ‘free energy minimization’ formulation due to Karl Friston (see e.g. Friston and Stephan (2007, Friston (2010 – see also Thornton (2010, Fiorillo (2010 A recurrent puzzle raised by critics of these models is that biological systems do not seem to avoid surprises. We do not simply seek a dark, unchanging chamber and stay there. This is the ‘Dark Room Problem’. Here, we describe the problem and further unpack the issues to which it speaks. Using the same format as the prologue of Eddington’s Space, Time and Gravitation (Eddington 1920 we present our discussion as a conversation between:An Information THEORIST (ThorntonA PHYSICIST (Friston A PHILOSOPHER (Clark

  17. Energy Efficient Smartphones: Minimizing the Energy Consumption of Smartphone GPUs using DVFS Governors

    KAUST Repository

    Ahmad, Enas M.

    2013-05-15

    Modern smartphones are being designed with increasing processing power, memory capacity, network communication, and graphics performance. Although all of these features are enriching and expanding the experience of a smartphone user, they are significantly adding an overhead on the limited energy of the battery. This thesis aims at enhancing the energy efficiency of modern smartphones and increasing their battery life by minimizing the energy consumption of smartphones Graphical Processing Unit (GPU). Smartphone operating systems are becoming fully hardware-accelerated, which implies relying on the GPU power for rendering all application graphics. In addition, the GPUs installed in smartphones are becoming more and more powerful by the day. This raises an energy consumption concern. We present a novel implementation of GPU Scaling Governors, a Dynamic Voltage and Frequency Scaling (DVFS) scheme implemented in the Android kernel to dynamically scale the GPU. The scheme includes four main governors: Performance, Powersave, Ondmand, and Conservative. Unlike previous studies which looked into the power efficiency of mobile GPUs only through simulation and power estimations, we have implemented our approach on a real modern smartphone GPU, and acquired actual energy measurements using an external power monitor. Our results show that the energy consumption of smartphones can be reduced up to 15% using the Conservative governor in 2D rendering mode, and up to 9% in 3D rendering mode, with minimal effect on the performance.

  18. Energy-efficient ECG compression on wireless biosensors via minimal coherence sensing and weighted ℓ₁ minimization reconstruction.

    Science.gov (United States)

    Zhang, Jun; Gu, Zhenghui; Yu, Zhu Liang; Li, Yuanqing

    2015-03-01

    Low energy consumption is crucial for body area networks (BANs). In BAN-enabled ECG monitoring, the continuous monitoring entails the need of the sensor nodes to transmit a huge data to the sink node, which leads to excessive energy consumption. To reduce airtime over energy-hungry wireless links, this paper presents an energy-efficient compressed sensing (CS)-based approach for on-node ECG compression. At first, an algorithm called minimal mutual coherence pursuit is proposed to construct sparse binary measurement matrices, which can be used to encode the ECG signals with superior performance and extremely low complexity. Second, in order to minimize the data rate required for faithful reconstruction, a weighted ℓ1 minimization model is derived by exploring the multisource prior knowledge in wavelet domain. Experimental results on MIT-BIH arrhythmia database reveals that the proposed approach can obtain higher compression ratio than the state-of-the-art CS-based methods. Together with its low encoding complexity, our approach can achieve significant energy saving in both encoding process and wireless transmission.

  19. Minimizing energy consumption of accelerators and storage ring facilities

    Energy Technology Data Exchange (ETDEWEB)

    Barton, M. Q.; Gerke, H.; Loew, G. A.; Lundy, R. A.; Schnell, W.

    1980-01-01

    The discussion of energy usage falls naturally into three parts. The first is a review of what the problem is, the second is a description of steps that can be taken to conserve energy at existing facilities, and the third is a review of the implications of energy consumption on future facilities.

  20. Cupolas minimize the energy required to melt ferrous alloys

    Energy Technology Data Exchange (ETDEWEB)

    Draper, A B

    1979-05-01

    Historically the cupola has been the most effective furnace for melting cast irons. Although its supremacy was challenged by electric melting furnaces in the 1960's, persisting energy scarcity and high cost have encouraged a resurgence of interest in cupola technology. Using the optimum design features of modern cupolas and the best melting practices, they can achieve melting efficiencies of 45% or more based on the energy value of the original coal. In contrast, electric melting only uses 21% of the energy in coal. Despite these facts, many foundrymen fear that there will be problems because of poor metallurgical control if they use cupolas. Yet experience has proven otherwise. In terms of energy conservation and economy it is better to use large cupolas as scrap melters in the steel industry. Yet there is still a deep rooted prejudice against the cupola plus basic oxygen furnace route to steel making.

  1. Drivers of Bacterial Maintenance and Minimal Energy Requirements.

    Science.gov (United States)

    Kempes, Christopher P; van Bodegom, Peter M; Wolpert, David; Libby, Eric; Amend, Jan; Hoehler, Tori

    2017-01-01

    Microbes maintain themselves through a variety of processes. Several of these processes can be reduced or shut down entirely when resource availability declines. In pure culture conditions with ample substrate supply, a relationship between the maximum growth rate and the energy invested in maintenance has been reported widely. However, at the other end of the resources spectrum, bacteria are so extremely limited by energy that no growth occurs and metabolism is constrained to the most essential functions only. These minimum energy requirements have been called the basal power requirement. While seemingly different from each other, both aspects are likely components of a continuum of regulated maintenance processes. Here, we analyze cross-species tradeoffs in cellular physiology over the range of bacterial size and energy expenditure and determine the contributions to maintenance metabolism at each point along the size-energy spectrum. Furthermore, by exploring the simplest bacteria within this framework- which are most affected by maintenance constraints- we uncover which processes become most limiting. For the smallest species, maintenance metabolism converges on total metabolism, where we predict that maintenance is dominated by the repair of proteins. For larger species the relative costs of protein repair decrease and maintenance metabolism is predicted to be dominated by the repair of RNA components. These results provide new insights into which processes are likely to be regulated in environments that are extremely limited by energy.

  2. Discretized energy minimization in a wave guide with point sources

    Science.gov (United States)

    Propst, G.

    1994-01-01

    An anti-noise problem on a finite time interval is solved by minimization of a quadratic functional on the Hilbert space of square integrable controls. To this end, the one-dimensional wave equation with point sources and pointwise reflecting boundary conditions is decomposed into a system for the two propagating components of waves. Wellposedness of this system is proved for a class of data that includes piecewise linear initial conditions and piecewise constant forcing functions. It is shown that for such data the optimal piecewise constant control is the solution of a sparse linear system. Methods for its computational treatment are presented as well as examples of their applicability. The convergence of discrete approximations to the general optimization problem is demonstrated by finite element methods.

  3. Probing gravitational non-minimal coupling with dark energy surveys

    Science.gov (United States)

    Geng, Chao-Qiang; Lee, Chung-Chi; Wu, Yi-Peng

    2017-03-01

    We investigate observational constraints on a specific one-parameter extension to the minimal quintessence model, where the quintessence field acquires a quadratic coupling to the scalar curvature through a coupling constant ξ . The value of ξ is highly suppressed in typical tracker models if the late-time cosmic acceleration is driven at some field values near the Planck scale. We test ξ in a second class of models in which the field value today becomes a free model parameter. We use the combined data from type-Ia supernovae, cosmic microwave background, baryon acoustic oscillations and matter power spectrum, to weak lensing measurements and find a best-fit value ξ {>}0.289 where ξ = 0 is excluded outside the 95% confidence region. The effective gravitational constant G_eff subject to the hint of a non-zero ξ is constrained to -0.003Solar System tests.

  4. Entropic measure to prevent energy over-minimization in molecular dynamics simulations

    CERN Document Server

    Rydzewski, Jakub; Nowak, Wieslaw

    2015-01-01

    Geometry optimization via energy minimization is one of the most common steps in computer modelling of biological structures. Nowadays computer power encourage numerous researches to use conjugated gradient minimizations exceeding 1000 steps. However, our research reveals that such over-minimization may lead to thermodynamically unstable conformations. We show that these conformations are not optimum starting points for equilibrium molecular dynamics simulations. We propose a measure based on the Pareto front of total entropy for quality assessment of minimized protein which warrants a proper selection of minimization steps.

  5. Portfolio management : minimizing energy costs in an open access market

    Energy Technology Data Exchange (ETDEWEB)

    Greenberg, P. [U.S. Generating Company (United States)

    1998-09-01

    This presentation addressed the issue of evolving market structures for electric utilities, discussed portfolio management in an open access market and enumerated critical abilities that will be required for success in the new marketplace. Viewgraphs provided information regarding the current retail restructuring landscape and merchant plant activity by region. Bar graphs were included to represent the growth of power marketing and the results of utility divestiture auctions. Critical capabilities to successfully optimize a competitive energy portfolio, including functional integration, teamwork and goals alignment, the aggressive use of information technology, liquidity, and risk management, were discussed at length. As an example of the new approach, the structure and operating plans of PG and E, one of the largest unregulated energy trading company in the U.S., were reviewed. In brief, the company plans to be aggressive in all competitive energy markets, to focus on asset development and acquisition, and to gain liquidity through trading and marketing. 16 figs.

  6. Twisted tubular photobioreactor fluid dynamics evaluation for energy consumption minimization

    NARCIS (Netherlands)

    Gómez-Pérez, C.A.; Espinosa Oviedo, J.J.; Montenegro Ruiz, L.C.; Boxtel, van A.J.B.

    2017-01-01

    This paper discusses a new tubular PhotoBioReactor (PBR) called twisted tubular PBR. The geometry of a twisted tubular PBR induces swirl mixing to guarantee good exposure of microalgae to Light-Dark (LD) cycles and to the nutrients and dissolved CO 2 . The paper analyses the energy uptake for fluid

  7. Fast Energy Minimization of large Polymers Using Constrained Optimization

    Energy Technology Data Exchange (ETDEWEB)

    Todd D. Plantenga

    1998-10-01

    A new computational technique is described that uses distance constraints to calculate empirical potential energy minima of partially rigid molecules. A constrained minimuzation algorithm that works entirely in Cartesian coordinates is used. The algorithm does not obey the constraints until convergence, a feature that reduces ill-conditioning and allows constrained local minima to be computed more quickly than unconstrained minima. Computational speedup exceeds the 3-fold factor commonly obtained in constained molecular dynamics simulations, where the constraints must be strictly obeyed at all times.

  8. Minimization of the energy costs for operating magnetic tunnel junctions

    Science.gov (United States)

    Farhat, Ilyas A. H.; Gale, E.; Isakovic, A. F.

    2015-03-01

    Increasing prospects of utilizing the STT-MRAM calls for the re-assessment of the overall energy (power) cost of operating magnetic tunnel junctions and related elements. This motivates our design, nanofabrication and characterization of simple tri-layer magnetic tunnel junctions which show measurable decrease in the operating energy cost. The MTJs we report about rely on nanoengineering interfaces between the insulating and magnetic layers in such a way that the area of the hysteresis loops can be controlled in one or both magnetic layers. Our TMR coefficient ranges from 45% to 130%, depending on the MTJ layer materials, and can be anticipated to be further increased. We also report the study of the TMR dependence on the RA product, as an important interface parameter. Lastly, we present an analysis of MTJ parameters affected by our approach and a perspective on further improvements, focusing on the device design parameters relevant for the integration of this type of MTJs. This work is supported by the SRC-ATIC Grant 2012-VJ-2335. A part of this work is being performed at Cornell University CNF, a member of NNIN. We thank CNF staff for the support.

  9. Minimizing the water and air impacts of unconventional energy extraction

    Science.gov (United States)

    Jackson, R. B.

    2014-12-01

    Unconventional energy generates income and, done well, can reduce air pollution compared to other fossil fuels and even water use compared to fossil fuels and nuclear energy. Alternatively, it could slow the adoption of renewables and, done poorly, release toxic chemicals into water and air. Based on research to date, some primary threats to water resources come from surface spills, wastewater disposal, and drinking-water contamination through poor well integrity. For air resources, an increase in volatile organic compounds and air toxics locally is a potential health threat, but the switch from coal to natural gas for electricity generation will reduce sulfur, nitrogen, mercury, and particulate pollution regionally. Critical needs for future research include data for 1) estimated ultimate recovery (EUR) of unconventional hydrocarbons; 2) the potential for further reductions of water requirements and chemical toxicity; 3) whether unconventional resource development alters the frequency of well-integrity failures; 4) potential contamination of surface and ground waters from drilling and spills; and 5) the consequences of greenhouse gases and air pollution on ecosystems and human health.

  10. Spinning gas clouds: III. Solutions of minimal energy with precession

    CERN Document Server

    Gaffet, B

    2003-01-01

    We consider the model of rotating and expanding gas cloud originally proposed by Ovsiannikov (1956 Dokl. Akad. Nauk SSSR 111 47) and Dyson (1968 J. Math. Mech. 18 91). Under the restricting assumptions of an adiabatic index gamma = 5/3 and of vorticity-free motion, this has been shown (Gaffet 2001 J. Phys. A: Math. Gen. 34 2097) to be a Liouville integrable Hamiltonian system. In the present work, we consider the precessing solutions where the cloud does not retain a fixed rotation axis. Choosing for definiteness a particular set of constants of motion (which corresponds to a minimum of the energy), we show that a separation of variables occurs, and that the equations of motion are reducible to the form of a Riccati equation, whose integration merely involves an elliptic integral.

  11. Spinning gas clouds: III. Solutions of minimal energy with precession

    Science.gov (United States)

    Gaffet, B.

    2003-05-01

    We consider the model of rotating and expanding gas cloud originally proposed by Ovsiannikov (1956 Dokl. Akad. Nauk SSSR 111 47) and Dyson (1968 J. Math. Mech. 18 91). Under the restricting assumptions of an adiabatic index gamma = 5/3 and of vorticity-free motion, this has been shown (Gaffet 2001 J. Phys. A: Math. Gen. 34 2097) to be a Liouville integrable Hamiltonian system. In the present work, we consider the precessing solutions where the cloud does not retain a fixed rotation axis. Choosing for definiteness a particular set of constants of motion (which corresponds to a minimum of the energy), we show that a separation of variables occurs, and that the equations of motion are reducible to the form of a Riccati equation, whose integration merely involves an elliptic integral.

  12. Dark Energy Model with Non-Minimal Coupling and Cosmological Constant Boundary

    Institute of Scientific and Technical Information of China (English)

    张晓菲

    2011-01-01

    In this paper, we study a kind of dark energy models in the framework of the non-minimal coupling. With this kind of models, dark energy could cross the cosmological constant boundary, and at early time, dark energy could have "tracking" behavior.

  13. A new method of constructing energy momentum tensor of non-minimally coupled theories

    CERN Document Server

    Mukherjee, Pradip; Roy, Amit Singha

    2016-01-01

    A new method of constructing conserved energy momentum tensor of non minimally coupled theories is developed from first principles. This method is based on Noether procedure in the locally inertial system.

  14. Topologically stratified energy minimizers in a product Abelian field theory

    Directory of Open Access Journals (Sweden)

    Xiaosen Han

    2015-09-01

    Full Text Available We study a recently developed product Abelian gauge field theory by Tong and Wong hosting magnetic impurities. We first obtain a necessary and sufficient condition for the existence of a unique solution realizing such impurities in the form of multiple vortices. We next reformulate the theory into an extended model that allows the coexistence of vortices and anti-vortices. The two Abelian gauge fields in the model induce two species of magnetic vortex-lines resulting from Ns vortices and Ps anti-vortices (s=1,2 realized as the zeros and poles of two complex-valued Higgs fields, respectively. An existence theorem is established for the governing equations over a compact Riemann surface S which states that a solution with prescribed N1, N2 vortices and P1,P2 anti-vortices of two designated species exists if and only if the inequalities |N1+N2−(P1+P2|<|S|π,|N1+2N2−(P1+2P2|<|S|π, hold simultaneously, which give bounds for the ‘differences’ of the vortex and anti-vortex numbers in terms of the total surface area of S. The minimum energy of these solutions is shown to assume the explicit value E=4π(N1+N2+P1+P2, given in terms of several topological invariants, measuring the total tension of the vortex-lines.

  15. Topologically Stratified Energy Minimizers in a Product Abelian Field Theory

    CERN Document Server

    Han, Xiaosen

    2015-01-01

    The recently developed product Abelian gauge field theory by Tong and Wong hosting magnetic impurities is reformulated into an extended model that allows the coexistence of vortices and anti-vortices. The two Abelian gauge fields in the model induce two species of magnetic vortex-lines resulting from $N_s$ vortices and $P_s$ anti-vortices ($s=1,2$) realized as the zeros and poles of two complex-valued Higgs fields, respectively. An existence theorem is established for the governing equations over a compact Riemann surface $S$ which states that a solution with prescribed $N_1, N_2$ vortices and $P_1,P_2$ anti-vortices of two designated species exists if and only if the inequalities \\[ \\left|N_1+N_2-(P_1+P_2)\\right|<\\frac{|S|}{\\pi},\\quad \\left|N_1+2N_2-(P_1+2P_2)\\right|<\\frac{|S|}{\\pi}, \\] hold simultaneously, which give bounds for the `differences' of the vortex and anti-vortex numbers in terms of the total surface area of $S$. The minimum energy of these solutions is shown to assume the explicit value \\...

  16. Empirical rheological law of multiphase rocks: Energy minimizing approach independent of bound theory

    Institute of Scientific and Technical Information of China (English)

    ZANG Shaoxian; JIANG Yan; WEI Rongqiang

    2003-01-01

    Based on energy minimizing approach of bound theory, the influence of the distribution of constituent minerals on rheological property of rocks is discussed. Energy minimizing approach independent of the bound theory is advanced after the constraint condition is improved. The strength of four multiphase rocks is calculated with the new empirical rheological law. Results indicate that the new law has a reasonable physical explanation and fits the experimental data very well.

  17. A comparative study of energy minimization methods for Markov random fields with smoothness-based priors.

    Science.gov (United States)

    Szeliski, Richard; Zabih, Ramin; Scharstein, Daniel; Veksler, Olga; Kolmogorov, Vladimir; Agarwala, Aseem; Tappen, Marshall; Rother, Carsten

    2008-06-01

    Among the most exciting advances in early vision has been the development of efficient energy minimization algorithms for pixel-labeling tasks such as depth or texture computation. It has been known for decades that such problems can be elegantly expressed as Markov random fields, yet the resulting energy minimization problems have been widely viewed as intractable. Recently, algorithms such as graph cuts and loopy belief propagation (LBP) have proven to be very powerful: for example, such methods form the basis for almost all the top-performing stereo methods. However, the tradeoffs among different energy minimization algorithms are still not well understood. In this paper we describe a set of energy minimization benchmarks and use them to compare the solution quality and running time of several common energy minimization algorithms. We investigate three promising recent methods graph cuts, LBP, and tree-reweighted message passing in addition to the well-known older iterated conditional modes (ICM) algorithm. Our benchmark problems are drawn from published energy functions used for stereo, image stitching, interactive segmentation, and denoising. We also provide a general-purpose software interface that allows vision researchers to easily switch between optimization methods. Benchmarks, code, images, and results are available at http://vision.middlebury.edu/MRF/.

  18. Electron-electron correlations in square-well quantum dots: direct energy minimization approach.

    Science.gov (United States)

    Goto, Hidekazu; Hirose, Kikuji

    2011-04-01

    Electron-electron correlations in two-dimensional square-well quantum dots are investigated using the direct energy minimization scheme. Searches for groundstate charges and spin configurations are performed with varying the sizes of dots and the number of electrons. For a two-electron system, a standout difference between the configurations with and without counting correlation energy is demonstrated. The emergence and melting of Wigner-molecule-like structures arising from the interplay between the kinetic energy and Coulombic interaction energy are described. Electron-electron correlation energies and addition energy spectra are calculated, and special electron numbers related to peculiar effects of the square well are extracted.

  19. Three-Dimensional Dirac Oscillator with Minimal Length: Novel Phenomena for Quantized Energy

    Directory of Open Access Journals (Sweden)

    Malika Betrouche

    2013-01-01

    Full Text Available We study quantum features of the Dirac oscillator under the condition that the position and the momentum operators obey generalized commutationrelations that lead to the appearance of minimal length with the order of the Planck length, ∆xmin=ℏ3β+β′, where β and β′ are two positive small parameters. Wave functions of the system and the corresponding energy spectrum are derived rigorously. The presence of the minimal length accompanies a quadratic dependence of the energy spectrum on quantum number n, implying the property of hard confinement of the system. It is shown that the infinite degeneracy of energy levels appearing in the usual Dirac oscillator is vanished by the presence of the minimal length so long as β≠0. Not only in the nonrelativistic limit but also in the limit of the standard case (β=β′=0, our results reduce to well known usual ones.

  20. Non-minimal coupling of torsion-matter satisfying null energy condition for wormhole solutions

    Energy Technology Data Exchange (ETDEWEB)

    Jawad, Abdul; Rani, Shamaila [COMSATS Institute of Information Technology, Department of Mathematics, Lahore (Pakistan)

    2016-12-15

    We explore wormhole solutions in a non-minimal torsion-matter coupled gravity by taking an explicit non-minimal coupling between the matter Lagrangian density and an arbitrary function of the torsion scalar. This coupling describes the transfer of energy and momentum between matter and torsion scalar terms. The violation of the null energy condition occurred through an effective energy-momentum tensor incorporating the torsion-matter non-minimal coupling, while normal matter is responsible for supporting the respective wormhole geometries. We consider the energy density in the form of non-monotonically decreasing function along with two types of models. The first model is analogous to the curvature-matter coupling scenario, that is, the torsion scalar with T-matter coupling, while the second one involves a quadratic torsion term. In both cases, we obtain wormhole solutions satisfying the null energy condition. Also, we find that the increasing value of the coupling constant minimizes or vanishes on the violation of the null energy condition through matter. (orig.)

  1. Foraging site selection of two subspecies of Bar-tailed Godwit Limosa lapponica : time minimizers accept greater predation danger than energy minimizers

    NARCIS (Netherlands)

    Duijns, Sjoerd; van Dijk, Jacintha G. B.; Spaans, Bernard; Jukema, Joop; de Boer, Willem F.; Piersma, Theunis

    2009-01-01

    Different spatial distributions Of food abundance and predators may urge birds to make a trade-off between food intake and danger. Such a trade-off might be solved in different ways in migrant birds that either follow a time-minimizing or energy-minimizing strategy; these strategies have been

  2. Foraging site selection of two subspecies of Bar-tailed Godwit Limosa lapponica: time minimizers accept greater predation danger than energy minimizers

    NARCIS (Netherlands)

    Duijns, S.; Dijk, van J.G.B.; Spaans, B.; Jukema, J.; Boer, de W.F.; Piersma, Th.

    2009-01-01

    Different spatial distributions of food abundance and predators may urge birds to make a trade-off between food intake and danger. Such a trade-off might be solved in different ways in migrant birds that either follow a time-minimizing or energy-minimizing strategy; these strategies have been

  3. Band offset formation at semiconductor heterojunctions through density-based minimization of interface energy

    Science.gov (United States)

    Tung, Raymond T.; Kronik, Leeor

    2016-08-01

    It is well known that the magnitude of band offset (BO) at any semiconductor heterojunction is directly derivable from the distribution of charge at that interface and that the latter is decided by a minimization of total energy. However, the fact that BO formation is governed by energy minimization has not been explicitly used in theoretical BO models, likely because the equilibrium charge densities at heterojunction interfaces appear difficult to predict, except via explicit calculation. In this paper, electron densities at a large number of (100), (110), and (111) oriented heterojunctions between lattice-matched, isovalent semiconductors with the zinc blende (ZB) structure have been calculated by first-principles methods and analyzed in detail for possible common characteristics among energy-minimized densities. Remarkably, the heterojunction electron density was found to largely depend only on the immediate, local atomic arrangement. In fact, it is so much so that a juxtaposition of local electron-densities generated in oligo-cells (LEGOs) accurately reproduced the charge densities that minimize the energy for the heterojunctions. Furthermore, the charge distribution for each bulk semiconductor was found to display a striking separability of its electrostatic effect into two neutral parts, associated with the cation and the anion, which are approximately transferrable among semiconductors. These discoveries form the basis of a neutral polyhedra theory (NPT) that approximately predicts the equilibrium charge density and BO of relaxed heterojunctions from the energy minimization requirement. Well-known experimentally observed characteristics of heterojunctions, such as the insensitivity of BO to heterojunction orientation and the identity of interface bonds, the transitivity rule, etc., are all in good agreement with the NPT. Therefore, energy minimization, which essentially decides the electronic properties of all other solid and molecular systems, also governs

  4. Green Energy in New Construction: Maximize Energy Savings and Minimize Cost

    Science.gov (United States)

    Ventresca, Joseph

    2010-01-01

    People often use the term "green energy" to refer to alternative energy technologies. But green energy doesn't guarantee maximum energy savings at a minimum cost--a common misconception. For school business officials, green energy means getting the lowest energy bills for the lowest construction cost, which translates into maximizing green energy…

  5. Consolidation of hydrophobic transition criteria by using an approximate energy minimization approach.

    Science.gov (United States)

    Patankar, Neelesh A

    2010-06-01

    Recent experimental work has successfully revealed pressure induced transition from Cassie to Wenzel state on rough hydrophobic substrates. Formulas, based on geometric considerations and imposed pressure, have been developed as transition criteria. In the past, transition has also been considered as a process of overcoming the energy barrier between the Cassie and Wenzel states. A unified understanding of the various considerations of transition has not been apparent. To address this issue, in this work, we consolidate the transition criteria with a homogenized energy minimization approach. This approach decouples the problem of minimizing the energy to wet the rough substrate, from the energy of the macroscopic drop. It is seen that the transition from Cassie to Wenzel state, due to depinning of the liquid-air interface, emerges from the approximate energy minimization approach if the pressure-volume energy associated with the impaled liquid in the roughness is included. This transition can be viewed as a process in which the work done by the pressure force is greater than the barrier due to the surface energy associated with wetting the roughness. It is argued that another transition mechanism, due to a sagging liquid-air interface that touches the bottom of the roughness grooves, is not typically relevant if the substrate roughness is designed such that the Cassie state is at lower energy compared to the Wenzel state.

  6. Molecular mechanics calculations of proteins. Comparison of different energy minimization strategies

    DEFF Research Database (Denmark)

    Christensen, I T; Jørgensen, Flemming Steen

    1997-01-01

    A general strategy for performing energy minimization of proteins using the SYBYL molecular modelling program has been developed. The influence of several variables including energy minimization procedure, solvation, dielectric function and dielectric constant have been investigated in order...... to develop a general method, which is capable of producing high quality protein structures. Avian pancreatic polypeptide (APP) and bovine pancreatic phospholipase A2 (BP PLA2) were selected for the calculations, because high quality X-ray structures exist and because all classes of secondary structure...

  7. Molecular mechanics calculations of proteins. Comparison of different energy minimization strategies

    DEFF Research Database (Denmark)

    Christensen, I T; Jørgensen, Flemming Steen

    1997-01-01

    A general strategy for performing energy minimization of proteins using the SYBYL molecular modelling program has been developed. The influence of several variables including energy minimization procedure, solvation, dielectric function and dielectric constant have been investigated in order...... evaluated by the length on hydrogen bonds. The dimensions of active site in BP PLA2 is very dependent on electrostatic interactions, due to the presence of the positively charged calcium ion. Thus, the distances between calcium and the calcium-coordinating groups were used as a quality index...

  8. Smart HVAC Control in IoT: Energy Consumption Minimization with User Comfort Constraints

    Directory of Open Access Journals (Sweden)

    Jordi Serra

    2014-01-01

    of heating, ventilation, and air conditioning (HVAC systems in smart grids with variable energy price. To that end, first, we propose an energy scheduling method that minimizes the energy consumption cost for a particular time interval, taking into account the energy price and a set of comfort constraints, that is, a range of temperatures according to user’s preferences for a given room. Then, we propose an energy scheduler where the user may select to relax the temperature constraints to save more energy. Moreover, thanks to the IoT paradigm, the user may interact remotely with the HVAC control system. In particular, the user may decide remotely the temperature of comfort, while the temperature and energy consumption information is sent through Internet and displayed at the end user’s device. The proposed algorithms have been implemented in a real testbed, highlighting the potential gains that can be achieved in terms of both energy and cost.

  9. Teardrop shapes minimize bending energy of fusion pores connecting planar bilayers

    Science.gov (United States)

    Ryham, Rolf J.; Ward, Mark A.; Cohen, Fredric S.

    2013-12-01

    A numerical gradient flow procedure was devised to characterize minimal energy shapes of fusion pores connecting two parallel planar bilayer membranes. Pore energy, composed of splay, tilt, and stretching, was obtained by modeling each bilayer as two monolayers and treating each monolayer of a bilayer membrane as a freely deformable surface described with a mean lipid orientation field. Voids between the two monolayers were prevented by a steric penalty formulation. Pore shapes were assumed to possess both axial and reflectional symmetry. For fixed pore radius and bilayer separation, the gradient flow procedure was applied to initially toroidal pore shapes. Using initially elliptical pore shapes yielded the same final shape. The resulting minimal pore shapes and energies were analyzed as a function of pore dimension and lipid composition. Previous studies either assumed or confined pore shapes, thereby tacitly supplying an unspecified amount of energy to maintain shape. The shapes derived in the present study were outputs of calculations and an externally provided energy was not supplied. Our procedure therefore yielded energy minima significantly lower than those reported in prior studies. The membrane of minimal energy pores bowed outward near the pore lumen, yielding a pore length that exceeded the distance between the two fusing membranes.

  10. Teleparallel dark energy with purely non-minimal coupling to gravity

    Energy Technology Data Exchange (ETDEWEB)

    Gu, Je-An, E-mail: jagu@ntu.edu.tw [Leung Center for Cosmology and Particle Astrophysics, National Taiwan University, Taipei, 10617, Taiwan (China); Lee, Chung-Chi, E-mail: g9522545@oz.nthu.edu.tw [Department of Physics, National Tsing Hua University, Hsinchu, 300, Taiwan (China); Geng, Chao-Qiang, E-mail: geng@phys.nthu.edu.tw [Department of Physics, National Tsing Hua University, Hsinchu, 300, Taiwan (China); National Center for Theoretical Sciences, Hsinchu, 300, Taiwan (China)

    2013-01-08

    We propose the simplest model of teleparallel dark energy with purely a non-minimal coupling to gravity but no self-potential, a single model possessing various interesting features: simplicity, self-potential-free, the guaranteed late-time cosmic acceleration driven by the non-minimal coupling to gravity, tracker behavior of the dark energy equation of state at earlier times, a crossing of the phantom divide at a late time, and the existence of a finite-time future singularity. We find the analytic solutions of the dark-energy scalar field respectively in the radiation, matter, and dark energy dominated eras, thereby revealing the above features. We further illustrate possible cosmic evolution patterns and present the observational constraint of this model obtained by numerical analysis and data fitting.

  11. Sobolev gradient approach for the time evolution related to energy minimization of Ginzburg-Landau functionals

    Science.gov (United States)

    Raza, Nauman; Sial, Sultan; Siddiqi, Shahid S.

    2009-04-01

    The Sobolev gradient technique has been discussed previously in this journal as an efficient method for finding energy minima of certain Ginzburg-Landau type functionals [S. Sial, J. Neuberger, T. Lookman, A. Saxena, Energy minimization using Sobolev gradients: application to phase separation and ordering, J. Comput. Phys. 189 (2003) 88-97]. In this article a Sobolev gradient method for the related time evolution is discussed.

  12. SOLUTIONS OF GINZBURG-LANDAU EQUATIONS WITH WEIGHT AND MINIMIZERS OF THE RENORMALIZED ENERGY

    Institute of Scientific and Technical Information of China (English)

    Kou Yanlei; Ding Shijin

    2007-01-01

    In this paper, it is proved that for any given d non-degenerate local minimum points of the renormalized energy of weighted Ginzburg-Landau eqautions, one can find solutions to the Ginzburg-Landau equations whose vortices tend to these d points. This provides the connections between solutions of a class of Ginzburg-Landau equations with weight and minimizers of the renormalized energy.

  13. Heteroclinic standing waves in defocussing DNLS equations -- Variational approach via energy minimization

    CERN Document Server

    Herrmann, Michael

    2010-01-01

    We study heteroclinic standing waves (dark solitons) in discrete nonlinear Schr\\"{o}dinger equations with defocussing nonlinearity. Our main result is a quite elementary existence proof for waves with monotone and odd profile, and relies on minimizing an appropriately defined energy functional. We also study the continuum limit and the numerical approximation of standing waves.

  14. Minimizing the Free Energy: A Computer Method for Teaching Chemical Equilibrium Concepts.

    Science.gov (United States)

    Heald, Emerson F.

    1978-01-01

    Presents a computer method for teaching chemical equilibrium concepts using material balance conditions and the minimization of the free energy. Method for the calculation of chemical equilibrium, the computer program used to solve equilibrium problems and applications of the method are also included. (HM)

  15. Energy levels of one-dimensional systems satisfying the minimal length uncertainty relation

    Science.gov (United States)

    Bernardo, Reginald Christian S.; Esguerra, Jose Perico H.

    2016-10-01

    The standard approach to calculating the energy levels for quantum systems satisfying the minimal length uncertainty relation is to solve an eigenvalue problem involving a fourth- or higher-order differential equation in quasiposition space. It is shown that the problem can be reformulated so that the energy levels of these systems can be obtained by solving only a second-order quasiposition eigenvalue equation. Through this formulation the energy levels are calculated for the following potentials: particle in a box, harmonic oscillator, Pöschl-Teller well, Gaussian well, and double-Gaussian well. For the particle in a box, the second-order quasiposition eigenvalue equation is a second-order differential equation with constant coefficients. For the harmonic oscillator, Pöschl-Teller well, Gaussian well, and double-Gaussian well, a method that involves using Wronskians has been used to solve the second-order quasiposition eigenvalue equation. It is observed for all of these quantum systems that the introduction of a nonzero minimal length uncertainty induces a positive shift in the energy levels. It is shown that the calculation of energy levels in systems satisfying the minimal length uncertainty relation is not limited to a small number of problems like particle in a box and the harmonic oscillator but can be extended to a wider class of problems involving potentials such as the Pöschl-Teller and Gaussian wells.

  16. Energy levels of one-dimensional systems satisfying the minimal length uncertainty relation

    Energy Technology Data Exchange (ETDEWEB)

    Bernardo, Reginald Christian S., E-mail: rcbernardo@nip.upd.edu.ph; Esguerra, Jose Perico H., E-mail: jesguerra@nip.upd.edu.ph

    2016-10-15

    The standard approach to calculating the energy levels for quantum systems satisfying the minimal length uncertainty relation is to solve an eigenvalue problem involving a fourth- or higher-order differential equation in quasiposition space. It is shown that the problem can be reformulated so that the energy levels of these systems can be obtained by solving only a second-order quasiposition eigenvalue equation. Through this formulation the energy levels are calculated for the following potentials: particle in a box, harmonic oscillator, Pöschl–Teller well, Gaussian well, and double-Gaussian well. For the particle in a box, the second-order quasiposition eigenvalue equation is a second-order differential equation with constant coefficients. For the harmonic oscillator, Pöschl–Teller well, Gaussian well, and double-Gaussian well, a method that involves using Wronskians has been used to solve the second-order quasiposition eigenvalue equation. It is observed for all of these quantum systems that the introduction of a nonzero minimal length uncertainty induces a positive shift in the energy levels. It is shown that the calculation of energy levels in systems satisfying the minimal length uncertainty relation is not limited to a small number of problems like particle in a box and the harmonic oscillator but can be extended to a wider class of problems involving potentials such as the Pöschl–Teller and Gaussian wells.

  17. Base station selection for energy efficient network operation with the majorization-minimization algorithm

    CERN Document Server

    Pollakis, Emmanuel; Stańczak, Slawomir

    2012-01-01

    In this paper, we study the problem of reducing the energy consumption in a mobile communication network; we select the smallest set of active base stations that can preserve the quality of service (the minimum data rate) required by the users. In more detail, we start by posing this problem as an integer programming problem, the solution of which shows the optimal assignment (in the sense of minimizing the total energy consumption) between base stations and users. In particular, this solution shows which base stations can then be switched off or put in idle mode to save energy. However, solving this problem optimally is intractable in general, so in this study we develop a suboptimal approach that builds upon recent techniques that have been successfully applied to, among other problems, sparse signal reconstruction, portfolio optimization, statistical estimation, and error correction. More precisely, we relax the original integer programming problem as a minimization problem where the objective function is ...

  18. Tracker Teleparallel Dark Energy with Purely Non-minimal Coupling to Gravity

    CERN Document Server

    Gu, Je-An; Geng, Chao-Qiang

    2012-01-01

    We investigate the teleparallel dark energy model with purely non-minimal coupling and without potential. We find the analytic solutions of the scalar field in the radiation, matter, and scalar field (or dark energy) dominated eras, respectively. These solutions indicate the tracker behavior in the radiation and matter dominated eras, while the equation of state $w_{\\phi}$ of the teleparallel dark energy is determined by the non-minimal coupling constant $\\xi$ but insensitive to the initial condition. In the scalar field dominated era, $w_{\\phi}$ monotonically decreases and goes to negative infinity at some finite time when $H$ goes to positive infinity, resulting in a future singularity. We also present the possible evolution patterns and the data fittings in this model.

  19. Online Speed Scaling Based on Active Job Count to Minimize Flow Plus Energy

    DEFF Research Database (Denmark)

    Lam, Tak-Wah; Lee, Lap Kei; To, Isaac K. K.;

    2013-01-01

    ) that changes speed discretely. This is in contrast to the previous algorithms which change the speed continuously. More interestingly, AJC admits a better competitive ratio, and without using extra speed. In the second part, we extend the study to a more general speed scaling model where the processor can......This paper is concerned with online scheduling algorithms that aim at minimizing the total flow time plus energy usage. The results are divided into two parts. First, we consider the well-studied “simple” speed scaling model and show how to analyze a speed scaling algorithm (called AJC...... enter a sleep state to further save energy. A new sleep management algorithm called IdleLonger is presented. This algorithm, when coupled with AJC, gives the first competitive algorithm for minimizing total flow time plus energy in the general model....

  20. Cooperative Content Distribution over Wireless Networks for Energy and Delay Minimization

    KAUST Repository

    Atat, Rachad

    2012-06-01

    Content distribution with mobile-to-mobile cooperation is studied. Data is sent to mobile terminals on a long range link then the terminals exchange the content using an appropriate short range wireless technology. Unicasting and multicasting are investigated, both on the long range and short range links. Energy minimization is formulated as an optimization problem for each scenario, and the optimal solutions are determined in closed form. Moreover, the schemes are applied in public safety vehicular networks, where Long Term Evolution (LTE) network is used for the long range link, while IEEE 802.11 p is considered for inter-vehicle collaboration on the short range links. Finally, relay-based multicasting is applied in high speed trains for energy and delay minimization. Results show that cooperative schemes outperform non-cooperative ones and other previous related work in terms of energy and delay savings. Furthermore, practical implementation aspects of the proposed methods are also discussed.

  1. Energy Minimization for Liquid Crystal Equilibrium with Electric and Flexoelectric Effects

    CERN Document Server

    Adler, J H; Benson, T R; Emerson, D B; MacLachlan, S P

    2014-01-01

    This paper outlines an energy-minimization finite-element approach to the modeling of equilibrium configurations for nematic liquid crystals in the presence of internal and external electric fields. The method targets minimization of system free energy based on the electrically and flexoelectrically augmented Frank-Oseen free energy models. The Hessian, resulting from the linearization of the first-order optimality conditions, is shown to be invertible for both models when discretized by a mixed finite-element method under certain assumptions. This implies that the intermediate discrete linearizations are well-posed. A coupled multigrid solver with Vanka-type relaxation is proposed and numerically vetted for approximation of the solution to the linear systems arising in the linearizations. Two electric model numerical experiments are performed with the proposed iterative solver. The first compares the algorithm's solution of a classical Freedericksz transition problem to the known analytical solution and demo...

  2. TCP over low-power and lossy networks: tuning the segment size to minimize energy consumption

    CERN Document Server

    Ayadi, Ahmed; Ros, David

    2010-01-01

    Low-power and Lossy Networks (LLNs), like wireless networks based upon the IEEE 802.15.4 standard, have strong energy constraints, and are moreover subject to frequent transmission errors, not only due to congestion but also to collisions and to radio channel conditions. This paper introduces an analytical model to compute the total energy consumption in an LLN due to the TCP protocol. The model allows us to highlight some tradeoffs as regards the choice of the TCP maximum segment size, of the Forward Error Correction (FEC) redundancy ratio, and of the number of link-layer retransmissions, in order to minimize the total energy consumption.

  3. Minimizing Characterization - Derived Waste at the Department of Energy Savannah River Site, Aiken, South Carolina

    Energy Technology Data Exchange (ETDEWEB)

    Van Pelt, R. S.; Amidon, M. B.; Reboul, S. H.

    2002-02-25

    Environmental restoration activities at the Department of Energy Savannah River Site (SRS) utilize innovative site characterization approaches and technologies that minimize waste generation. Characterization is typically conducted in phases, first by collecting large quantities of inexpensive data, followed by targeted minimally invasive drilling to collect depth-discrete soil/groundwater data, and concluded with the installation of permanent multi-level groundwater monitoring wells. Waste-reducing characterization methods utilize non-traditional drilling practices (sonic drilling), minimally intrusive (geoprobe, cone penetrometer) and non-intrusive (3-D seismic, ground penetration radar, aerial monitoring) investigative tools. Various types of sensor probes (moisture sensors, gamma spectroscopy, Raman spectroscopy, laser induced and X-ray fluorescence) and hydrophobic membranes (FLUTe) are used in conjunction with depth-discrete sampling techniques to obtain high-resolution 3-D plume profiles. Groundwater monitoring (short/long-term) approaches utilize multi-level sampling technologies (Strata-Sampler, Cone-Sipper, Solinst Waterloo, Westbay) and low-cost diffusion samplers for seepline/surface water sampling. Upon collection of soil and groundwater data, information is portrayed in a Geographic Information Systems (GIS) format for interpretation and planning purposes. At the SRS, the use of non-traditional drilling methods and minimally/non intrusive investigation approaches along with in-situ sampling methods has minimized waste generation and improved the effectiveness and efficiency of characterization activities.

  4. Minimization of Heat Energy Intensity in Food Production Companies Applying Sustainable Industrial Development Methods

    Directory of Open Access Journals (Sweden)

    Irina Kliopova

    2011-10-01

    Full Text Available Lithuanian food and drink sector of industry is characterized by high energy intensity, which is 29% higher than the EU average. At the confectionary plant chosen for the experiment, an environmental impact has been controlled and its maximum managed by creating different procedures to reduce pollution. Assessment of the plant's environmental costs has revealed that the energy costs amount to main part of the environmental ones (up to 55.4%. In recent years several energy efficiency projects have been implemented allowing minimizing the plant's energy intensity up to 15%. An algorithm of feasibility analysis of increasing thermal energy efficiency of the plant was suggested which could also be applied to other food industry plants. Demand for heat energy within the plant was evaluated for each technological process; the fuel and energy balance of the plant boiler-house was drawn up. It was revealed that huge heat energy losses were made during heat energy production and usage. During the research period a control system of significant environmental aspects was suggested, its objective function was estimated. Several environmental alternatives were suggested for optimization of the heat energy production processes. Three projects were chosen for the feasibility analysis. Results of technical, economic and environmental evaluations of Cleaner Production (CP innovations as well as conclusions made are presented in this article.

  5. Segmentation of Synchrotron Radiation micro-Computed Tomography Images using Energy Minimization via Graph Cuts

    Energy Technology Data Exchange (ETDEWEB)

    Meneses, Anderson A.M. [Federal University of Western Para (Brazil); Physics Institute, Rio de Janeiro State University (Brazil); Giusti, Alessandro [IDSIA (Dalle Molle Institute for Artificial Intelligence), University of Lugano (Switzerland); Almeida, Andre P. de, E-mail: apalmeid@gmail.com [Physics Institute, Rio de Janeiro State University (Brazil); Nuclear Engineering Program, Federal University of Rio de Janeiro (Brazil); Nogueira, Liebert; Braz, Delson [Nuclear Engineering Program, Federal University of Rio de Janeiro (Brazil); Almeida, Carlos E. de [Radiological Sciences Laboratory, Rio de Janeiro State University (Brazil); Barroso, Regina C. [Physics Institute, Rio de Janeiro State University (Brazil)

    2012-07-15

    The research on applications of segmentation algorithms to Synchrotron Radiation X-Ray micro-Computed Tomography (SR-{mu}CT) is an open problem, due to the interesting and well-known characteristics of SR images, such as the phase contrast effect. The Energy Minimization via Graph Cuts (EMvGC) algorithm represents state-of-art segmentation algorithm, presenting an enormous potential of application in SR-{mu}CT imaging. We describe the application of the algorithm EMvGC with swap move for the segmentation of bone images acquired at the ELETTRA Laboratory (Trieste, Italy). - Highlights: Black-Right-Pointing-Pointer Microstructures of Wistar rats' ribs are investigated with Synchrotron Radiation {mu}CT imaging. Black-Right-Pointing-Pointer The present work is part of a research on the effects of radiotherapy on the thoracic region. Black-Right-Pointing-Pointer Application of the Energy Minimization via Graph Cuts algorithm for segmentation is described.

  6. Deterministic and stochastic algorithms for resolving the flow fields in ducts and networks using energy minimization

    CERN Document Server

    Sochi, Taha

    2014-01-01

    Several deterministic and stochastic multi-variable global optimization algorithms (Conjugate Gradient, Nelder-Mead, Quasi-Newton, and Global) are investigated in conjunction with energy minimization principle to resolve the pressure and volumetric flow rate fields in single ducts and networks of interconnected ducts. The algorithms are tested with seven types of fluid: Newtonian, power law, Bingham, Herschel-Bulkley, Ellis, Ree-Eyring and Casson. The results obtained from all those algorithms for all these types of fluid agree very well with the analytically derived solutions as obtained from the traditional methods which are based on the conservation principles and fluid constitutive relations. The results confirm and generalize the findings of our previous investigations that the energy minimization principle is at the heart of the flow dynamics systems. The investigation also enriches the methods of Computational Fluid Dynamics for solving the flow fields in tubes and networks for various types of Newtoni...

  7. Structural differences of matrix metalloproteinases. Homology modeling and energy minimization of enzyme-substrate complexes

    DEFF Research Database (Denmark)

    Terp, G E; Christensen, I T; Jørgensen, Flemming Steen

    2000-01-01

    Matrix metalloproteinases are extracellular enzymes taking part in the remodeling of extracellular matrix. The structures of the catalytic domain of MMP1, MMP3, MMP7 and MMP8 are known, but structures of enzymes belonging to this family still remain to be determined. A general approach...... to the homology modeling of matrix metalloproteinases, exemplified by the modeling of MMP2, MMP9, MMP12 and MMP14 is described. The models were refined using an energy minimization procedure developed for matrix metalloproteinases. This procedure includes incorporation of parameters for zinc and calcium ions...... in the AMBER 4.1 force field, applying a non-bonded approach and a full ion charge representation. Energy minimization of the apoenzymes yielded structures with distorted active sites, while reliable three-dimensional structures of the enzymes containing a substrate in active site were obtained. The structural...

  8. B-spline image model for energy minimization-based optical flow estimation.

    Science.gov (United States)

    Le Besnerais, Guy; Champagnat, Frédéric

    2006-10-01

    Robust estimation of the optical flow is addressed through a multiresolution energy minimization. It involves repeated evaluation of spatial and temporal gradients of image intensity which rely usually on bilinear interpolation and image filtering. We propose to base both computations on a single pyramidal cubic B-spline model of image intensity. We show empirically improvements in convergence speed and estimation error and validate the resulting algorithm on real test sequences.

  9. Isometric immersions, energy minimization and self-similar buckling in non-Euclidean elastic sheets

    Science.gov (United States)

    Gemmer, John; Sharon, Eran; Shearman, Toby; Venkataramani, Shankar C.

    2016-04-01

    The edges of torn plastic sheets and growing leaves often display hierarchical buckling patterns. We show that this complex morphology i) emerges even in zero strain configurations, and ii) is driven by a competition between the two principal curvatures, rather than between bending and stretching. We identify the key role of branch point (or “monkey saddle”) singularities in generating complex wrinkling patterns in isometric immersions, and show how they arise naturally from minimizing the elastic energy.

  10. A non-minimally coupled quintom dark energy model on the warped DGP brane

    Energy Technology Data Exchange (ETDEWEB)

    Nozari, K; Azizi, T [Department of Physics, Faculty of Basic Sciences, University of Mazandaran, PO Box 47416-95447, Babolsar (Iran, Islamic Republic of); Setare, M R [Department of Science, University of Kurdistan, Pasdaran Ave, Sanandaj (Iran, Islamic Republic of); Behrouz, N [Department of Physics, Payam-e Nour University, PO Box 919, Mashad (Iran, Islamic Republic of)], E-mail: knozari@umz.ac.ir, E-mail: rezakord@ipm.ir, E-mail: t.azizi@umz.ac.ir

    2009-08-15

    We construct a quintom dark energy model with two non-minimally coupled scalar fields, one quintessence and the other phantom field, confined to the warped Dvali-Gabadadze-Porrati (DGP) brane. We show that this model accounts for crossing of the phantom divide line in appropriate subspaces of the model parameter space. This crossing occurs for both normal and self-accelerating branches of this DGP-inspired setup.

  11. Five dimensional minimally interacting holographic dark energy model in Brans-Dicke theory of gravitation

    Science.gov (United States)

    Reddy, D. R. K.; Anitha, S.; Umadevi, S.

    2016-11-01

    In this paper, we investigate five dimensional space-time filled with minimally interacting dark matter and holographic dark energy in Brans-Dicke (Phys. Rev. 124:925, 1961) scalar-tensor theory of gravitation. The exact solutions of the field equations are obtained using (i) special law of variation for Hubble's parameter that yields constant value of deceleration parameter and (ii) a relation between metric potentials. The physical and geometrical aspects of the model are also discussed.

  12. Energy Minimization for Parallel Real-Time Systems with Malleable Jobs and Homogeneous Frequencies

    OpenAIRE

    Fisher, Nathan; Goossens, Joël; Hettiarachchi, Pradeep M.; Paolillo, Antonio

    2013-01-01

    In this work, we investigate the potential utility of parallelization for meeting real-time constraints and minimizing energy. We consider malleable Gang scheduling of implicit-deadline sporadic tasks upon multiprocessors. We first show the non-necessity of dynamic voltage/frequency regarding optimality of our scheduling problem. We adapt the canonical schedule for DVFS multiprocessor platforms and propose a polynomial-time optimal processor/frequency-selection algorithm. We evaluate the perf...

  13. Reduction efficiency prediction of CENIBRA's recovery boiler by direct minimization of gibbs free energy

    OpenAIRE

    W. L. Silva; Ribeiro,J. C. T.; E. F.da Costa Jr; A. O. S.da Costa

    2008-01-01

    The reduction efficiency is an important variable during the black liquor burning process in the Kraft recovery boiler. This variable value is obtained by slow experimental routines and the delay of this measure disturbs the pulp and paper industry customary control. This paper describes an optimization approach for the reduction efficiency determination in the furnace bottom of the recovery boiler based on the minimization of the Gibbs free energy. The industrial data used in this study were...

  14. MINIMIZATION OF IMPACTS PERTAINING TO EXTERNAL AND INTERNAL ENERGY SECURITY THREATS OF THERMAL POWER PLANTS

    Directory of Open Access Journals (Sweden)

    V. Nagornov

    2012-01-01

    Full Text Available The paper contains a classification of internal and external threats for thermal power plants and recommendations on minimization of these risks. A set of concrete measures aimed at ensuring TPP energy security has been presented in the paper. The system comprises preventive measures aimed at reducing the possibilities of emergence and implementation of internal and external threats. The system also presupposes to decrease susceptibility of fuel- and energy supply systems to the threats, and application of liquidation measures that ensure elimination of emergency situation consequences and restoration of the conditions concerning fuel- and power supply to consumers.

  15. Free Energy Minimization Calculation of Complex Chemical Equilibria. Reduction of Silicon Dioxide with Carbon at High Temperature.

    Science.gov (United States)

    Wai, C. M.; Hutchinson, S. G.

    1989-01-01

    Discusses the calculation of free energy in reactions between silicon dioxide and carbon. Describes several computer programs for calculating the free energy minimization and their uses in chemistry classrooms. Lists 16 references. (YP)

  16. Smart HVAC Control in IoT: Energy Consumption Minimization with User Comfort Constraints

    Science.gov (United States)

    Verikoukis, Christos

    2014-01-01

    Smart grid is one of the main applications of the Internet of Things (IoT) paradigm. Within this context, this paper addresses the efficient energy consumption management of heating, ventilation, and air conditioning (HVAC) systems in smart grids with variable energy price. To that end, first, we propose an energy scheduling method that minimizes the energy consumption cost for a particular time interval, taking into account the energy price and a set of comfort constraints, that is, a range of temperatures according to user's preferences for a given room. Then, we propose an energy scheduler where the user may select to relax the temperature constraints to save more energy. Moreover, thanks to the IoT paradigm, the user may interact remotely with the HVAC control system. In particular, the user may decide remotely the temperature of comfort, while the temperature and energy consumption information is sent through Internet and displayed at the end user's device. The proposed algorithms have been implemented in a real testbed, highlighting the potential gains that can be achieved in terms of both energy and cost. PMID:25054163

  17. Smart HVAC control in IoT: energy consumption minimization with user comfort constraints.

    Science.gov (United States)

    Serra, Jordi; Pubill, David; Antonopoulos, Angelos; Verikoukis, Christos

    2014-01-01

    Smart grid is one of the main applications of the Internet of Things (IoT) paradigm. Within this context, this paper addresses the efficient energy consumption management of heating, ventilation, and air conditioning (HVAC) systems in smart grids with variable energy price. To that end, first, we propose an energy scheduling method that minimizes the energy consumption cost for a particular time interval, taking into account the energy price and a set of comfort constraints, that is, a range of temperatures according to user's preferences for a given room. Then, we propose an energy scheduler where the user may select to relax the temperature constraints to save more energy. Moreover, thanks to the IoT paradigm, the user may interact remotely with the HVAC control system. In particular, the user may decide remotely the temperature of comfort, while the temperature and energy consumption information is sent through Internet and displayed at the end user's device. The proposed algorithms have been implemented in a real testbed, highlighting the potential gains that can be achieved in terms of both energy and cost.

  18. Sculpting proteins interactively: continual energy minimization embedded in a graphical modeling system.

    Science.gov (United States)

    Surles, M C; Richardson, J S; Richardson, D C; Brooks, F P

    1994-02-01

    We describe a new paradigm for modeling proteins in interactive computer graphics systems--continual maintenance of a physically valid representation, combined with direct user control and visualization. This is achieved by a fast algorithm for energy minimization, capable of real-time performance on all atoms of a small protein, plus graphically specified user tugs. The modeling system, called Sculpt, rigidly constrains bond lengths, bond angles, and planar groups (similar to existing interactive modeling programs), while it applies elastic restraints to minimize the potential energy due to torsions, hydrogen bonds, and van der Waals and electrostatic interactions (similar to existing batch minimization programs), and user-specified springs. The graphical interface can show bad and/or favorable contacts, and individual energy terms can be turned on or off to determine their effects and interactions. Sculpt finds a local minimum of the total energy that satisfies all the constraints using an augmented Lagrange-multiplier method; calculation time increases only linearly with the number of atoms because the matrix of constraint gradients is sparse and banded. On a 100-MHz MIPS R4000 processor (Silicon Graphics Indigo), Sculpt achieves 11 updates per second on a 20-residue fragment and 2 updates per second on an 80-residue protein, using all atoms except non-H-bonding hydrogens, and without electrostatic interactions. Applications of Sculpt are described: to reverse the direction of bundle packing in a designed 4-helix bundle protein, to fold up a 2-stranded beta-ribbon into an approximate beta-barrel, and to design the sequence and conformation of a 30-residue peptide that mimics one partner of a protein subunit interaction. Computer models that are both interactive and physically realistic (within the limitations of a given force field) have 2 significant advantages: (1) they make feasible the modeling of very large changes (such as needed for de novo design), and

  19. Hierarchical particle swarm optimizer for minimizing the non-convex potential energy of molecular structure.

    Science.gov (United States)

    Cheung, Ngaam J; Shen, Hong-Bin

    2014-11-01

    The stable conformation of a molecule is greatly important to uncover the secret of its properties and functions. Generally, the conformation of a molecule will be the most stable when it is of the minimum potential energy. Accordingly, the determination of the conformation can be solved in the optimization framework. It is, however, not an easy task to achieve the only conformation with the lowest energy among all the potential ones because of the high complexity of the energy landscape and the exponential computation increasing with molecular size. In this paper, we develop a hierarchical and heterogeneous particle swarm optimizer (HHPSO) to deal with the problem in the minimization of the potential energy. The proposed method is evaluated over a scalable simplified molecular potential energy function with up to 200 degrees of freedom and a realistic energy function of pseudo-ethane molecule. The experimental results are compared with other six PSO variants and four genetic algorithms. The results show HHPSO is significantly better than the compared PSOs with p-value less than 0.01277 over molecular potential energy function.

  20. Predicting Consensus Structures for RNA Alignments Via Pseudo-Energy Minimization

    Directory of Open Access Journals (Sweden)

    Junilda Spirollari

    2009-01-01

    Full Text Available Thermodynamic processes with free energy parameters are often used in algorithms that solve the free energy minimization problem to predict secondary structures of single RNA sequences. While results from these algorithms are promising, an observation is that single sequence-based methods have moderate accuracy and more information is needed to improve on RNA secondary structure prediction, such as covariance scores obtained from multiple sequence alignments. We present in this paper a new approach to predicting the consensus secondary structure of a set of aligned RNA sequences via pseudo-energy minimization. Our tool, called RSpredict, takes into account sequence covariation and employs effective heuristics for accuracy improvement. RSpredict accepts, as input data, a multiple sequence alignment in FASTA or ClustalW format and outputs the consensus secondary structure of the input sequences in both the Vienna style Dot Bracket format and the Connectivity Table format. Our method was compared with some widely used tools including KNetFold, Pfold and RNAalifold. A comprehensive test on different datasets including Rfam sequence alignments and a multiple sequence alignment obtained from our study on the Drosophila X chromosome reveals that RSpredict is competitive with the existing tools on the tested datasets. RSpredict is freely available online as a web server and also as a jar file for download at http:// datalab.njit.edu/biology/RSpredict.

  1. Ten scenarios from early radiation to late time acceleration with a minimally coupled dark energy

    CERN Document Server

    Fay, Stephane

    2015-01-01

    We consider General Relativity with matter, radiation and a minimally coupled dark energy defined by an equation of state w. Using dynamical system method, we find the equilibrium points of such a theory assuming an expanding Universe and a positive dark energy density. Two of these points correspond to classical radiation and matter dominated epochs for the Universe. For the other points, dark energy mimics matter, radiation or accelerates Universe expansion. We then look for possible sequences of epochs describing a Universe starting with some radiation dominated epoch(s) (mimicked or not by dark energy), then matter dominated epoch(s) (mimicked or not by dark energy) and ending with an accelerated expansion. We find ten sequences able to follow this Universe history without singular behaviour of w at some saddle points. Most of them are new in dark energy literature. To get more than these ten sequences, w has to be singular at some specific saddle equilibrium points. This is an unusual mathematical proper...

  2. The exponentiated Hencky-logarithmic strain energy. Part II: Coercivity, planar polyconvexity and existence of minimizers

    Science.gov (United States)

    Neff, Patrizio; Lankeit, Johannes; Ghiba, Ionel-Dumitrel; Martin, Robert; Steigmann, David

    2015-08-01

    We consider a family of isotropic volumetric-isochoric decoupled strain energies based on the Hencky-logarithmic (true, natural) strain tensor log U, where μ > 0 is the infinitesimal shear modulus, is the infinitesimal bulk modulus with the first Lamé constant, are dimensionless parameters, is the gradient of deformation, is the right stretch tensor and is the deviatoric part (the projection onto the traceless tensors) of the strain tensor log U. For small elastic strains, the energies reduce to first order to the classical quadratic Hencky energy which is known to be not rank-one convex. The main result in this paper is that in plane elastostatics the energies of the family are polyconvex for , extending a previous finding on its rank-one convexity. Our method uses a judicious application of Steigmann's polyconvexity criteria based on the representation of the energy in terms of the principal invariants of the stretch tensor U. These energies also satisfy suitable growth and coercivity conditions. We formulate the equilibrium equations, and we prove the existence of minimizers by the direct methods of the calculus of variations.

  3. Sufficient minimal model for DNA denaturation: Integration of harmonic scalar elasticity and bond energies.

    Science.gov (United States)

    Singh, Amit Raj; Granek, Rony

    2016-10-14

    We study DNA denaturation by integrating elasticity - as described by the Gaussian network model - with bond binding energies, distinguishing between different base pairs and stacking energies. We use exact calculation, within the model, of the Helmholtz free-energy of any partial denaturation state, which implies that the entropy of all formed "bubbles" ("loops") is accounted for. Considering base pair bond removal single events, the bond designated for opening is chosen by minimizing the free-energy difference for the process, over all remaining base pair bonds. Despite of its great simplicity, for several known DNA sequences our results are in accord with available theoretical and experimental studies. Moreover, we report free-energy profiles along the denaturation pathway, which allow to detect stable or meta-stable partial denaturation states, composed of bubble, as local free-energy minima separated by barriers. Our approach allows to study very long DNA strands with commonly available computational power, as we demonstrate for a few random sequences in the range 200-800 base-pairs. For the latter, we also elucidate the self-averaging property of the system. Implications for the well known breathing dynamics of DNA are elucidated.

  4. Sufficient minimal model for DNA denaturation: Integration of harmonic scalar elasticity and bond energies

    Science.gov (United States)

    Singh, Amit Raj; Granek, Rony

    2016-10-01

    We study DNA denaturation by integrating elasticity — as described by the Gaussian network model — with bond binding energies, distinguishing between different base pairs and stacking energies. We use exact calculation, within the model, of the Helmholtz free-energy of any partial denaturation state, which implies that the entropy of all formed "bubbles" ("loops") is accounted for. Considering base pair bond removal single events, the bond designated for opening is chosen by minimizing the free-energy difference for the process, over all remaining base pair bonds. Despite of its great simplicity, for several known DNA sequences our results are in accord with available theoretical and experimental studies. Moreover, we report free-energy profiles along the denaturation pathway, which allow to detect stable or meta-stable partial denaturation states, composed of bubble, as local free-energy minima separated by barriers. Our approach allows to study very long DNA strands with commonly available computational power, as we demonstrate for a few random sequences in the range 200-800 base-pairs. For the latter, we also elucidate the self-averaging property of the system. Implications for the well known breathing dynamics of DNA are elucidated.

  5. Minimizing Energy Cost in Electric Arc Furnace Steel Making by Optimal Control Designs

    Directory of Open Access Journals (Sweden)

    Er-wei Bai

    2014-01-01

    Full Text Available Production cost in steel industry is a challenge issue and energy optimization is an important part. This paper proposes an optimal control design aiming at minimizing the production cost of the electric arc furnace steel making. In particular, it is shown that with the structure of an electric arc furnace, the production cost which is a linear programming problem can be solved by the tools of linear quadratic regulation control design that not only provides an optimal solution but also is in a feedback form. Modeling and control designs are validated by the actual production data sets.

  6. Computational Potential Energy Minimization Studies on the Prion AGAAAAGA Amyloid Fibril Molecular Structures

    CERN Document Server

    Zhang, Jiapu

    2012-01-01

    X-ray crystallography, NMR (Nuclear Magnetic Resonance) spectroscopy, and dual polarization interferometry, etc are indeed very powerful tools to determine the 3D structures of proteins (including the membrane proteins), though they are time-consuming and costly. However, for some proteins, due to their unstable, noncrystalline and insoluble nature, these tools cannot work. Under this condition, mathematical and physical theoretical methods and computational approaches allow us to obtain a description of the protein 3D structure at a submicroscopic level. This Chapter presents some practical and useful mathematical optimization computational approaches to produce 3D structures of the Prion AGAAAAGA Amyloid Fibrils, from a potential energy minimization point of view.

  7. GMIN: A computerized chemical equilibrium model using a constrained minimization of the Gibbs free energy

    Energy Technology Data Exchange (ETDEWEB)

    Felmy, A.R.

    1990-04-01

    This document is a user's manual and technical reference for the computerized chemical equilibrium model GMIN. GMIN calculates the chemical composition of systems composed of pure solid phases, solid-solution phases, gas phases, adsorbed phases, and the aqueous phase. In the aqueous phase model, the excess solution free energy is modeled by using the equations developed by PITZER and his coworkers, which are valid to high ionic strengths. The Davies equation can also be used. Activity coefficients for nonideal soild-solution phases are calculated using parameters of polynomial expansion in mole fraction of the excess free energy of mixing. The free energy of adsorbed phase species is described by the triple-layer site-binding model. The mathematical algorithm incorporated into GMIN is based upon a constrained minimization of the Gibbs free energy. This algorithm is numerically stable and reliably converges to a free energy minimum. The data base for GMIN contains all standard chemical potentials and Pitzer ion-interaction parameters necessary to model the system Na-K-Ca-Mg-H-Cl-SO{sub 4}-CO{sub 2}-B(OH){sub 4}-H{sub 2}0 at 25{degrees}C.

  8. Energy Efficient Optical Networks with Minimized Non-Renewable Power Consumption

    Directory of Open Access Journals (Sweden)

    Xiaowen Dong

    2012-05-01

    Full Text Available Recent studies have shown that the Information and Communication Technology (ICT industry is responsible for about 2% of the global emission of CO2 and this percentage is expected to increase as the internet expands in bandwidth and reach. In this paper we propose a hybrid-power IP over WDM network where renewable energy is used to reduce the CO2 emission of IP over WDM networks. A Linear Programming (LP model and a novel heuristic are developed to minimize the non-renewable power consumption in the “hybrid-power” IP over WDM network. The performance of the network is studied considering two topologies, the NSFNET and the USNET. Compared with routing in the electronic layer, the results show that routing in the optical layer coupled with using renewable energy significantly reduces the CO2 emissions of the IP over WDM network by up to 73% for the NSFNET and 69% for the USNET, and the proposed heuristic has little impact on the QoS. We also develop an LP model to identify the impact of the location of nodes employing renewable energy on the non-renewable power consumption of the network. The results show that the optimum location of nodes employing renewable energy is determined according to the output power of the renewable energy sources and the power consumption of the nodes.

  9. Methods of Minimization of Calculations in High Energy Physics: 2. Minimization of number of vectors in problem

    OpenAIRE

    Bondarev, Alexander L.

    1997-01-01

    The various ways to reduce number of vectors describing condition of particles for high energy physics problems are presented. In particular decomposition of any vector with respect to the basis, consisting of any four linearly independent vectors, including the orthonormal basis; construction of orthonormal bases from vectors of a problem; expression of one vector of problem through other is considered.

  10. Zero-Temperature Limit of a Convergent Algorithm to Minimize the Bethe Free Energy

    CERN Document Server

    Werner, Tomas

    2011-01-01

    After the discovery that fixed points of loopy belief propagation coincide with stationary points of the Bethe free energy, several researchers proposed provably convergent algorithms to directly minimize the Bethe free energy. These algorithms were formulated only for non-zero temperature (thus finding fixed points of the sum-product algorithm) and their possible extension to zero temperature is not obvious. We present the zero-temperature limit of the double-loop algorithm by Heskes, which converges a max-product fixed point. The inner loop of this algorithm is max-sum diffusion. Under certain conditions, the algorithm combines the complementary advantages of the max-product belief propagation and max-sum diffusion (LP relaxation): it yields good approximation of both ground states and max-marginals.

  11. Digital nuclear radiation spectroscopy: Hardware requirements to minimize energy resolution degradation

    Energy Technology Data Exchange (ETDEWEB)

    Riva, M., E-mail: Marco.Riva@enea.it; Esposito, B.; Marocco, D.; Belli, F.

    2015-10-15

    Highlights: • Systematic requirement analysis of the digitizing process. • Synthetic pulses with different Full Width Half Maximum (FWHM). • Statistical and systematic error study. • Effects of the pulse amplitude reduction respect to the full scale on the error. • Hardware architecture considerations. - Abstract: Nuclear radiation spectroscopy is now often relying on digital acquisition techniques. The present paper addresses the problem of analyzing the requirements of the digitizer in terms of sampling frequency and number of bits to minimize the energy resolution degradation caused by the digitizing process. The analysis is performed using synthetic pulses (with different amplitude and Full Width Half Maximum) of typical nuclear spectroscopy detectors and the pulse area as energy estimate. Additional relevant issues, such as the hardware architecture and the data throughput speed, are also discussed.

  12. Real-Time Velocity Optimization to Minimize Energy Use in Passenger Vehicles

    Directory of Open Access Journals (Sweden)

    Thomas Levermore

    2016-12-01

    Full Text Available Energy use in internal combustion engine passenger vehicles contributes directly to CO 2 emissions and fuel consumption, as well as producing a number of air pollutants. Optimizing the vehicle velocity by utilising upcoming road information is an opportunity to minimize vehicle energy use without requiring mechanical design changes. Dynamic programming is capable of such an optimization task and is shown in simulation to produce fuel savings, on average 12%, compared to real driving data; however, in this paper it is also applied in real time on a Raspberry Pi, a low cost miniature computer, in situ in a vehicle. A test drive was undertaken with driver feedback being provided by a dynamic programming algorithm, and the results are compared to a simulated intelligent cruise control system that can follow the algorithm results precisely. An 8% reduction in fuel with no loss in time is reported compared to the test driver.

  13. Parameter Estimation and Energy Minimization for Region-Based Semantic Segmentation.

    Science.gov (United States)

    Kumar, M Pawan; Turki, Haithem; Preston, Dan; Koller, Daphne

    2015-07-01

    We consider the problem of parameter estimation and energy minimization for a region-based semantic segmentation model. The model divides the pixels of an image into non-overlapping connected regions, each of which is to a semantic class. In the context of energy minimization, the main problem we face is the large number of putative pixel-to-region assignments. We address this problem by designing an accurate linear programming based approach for selecting the best set of regions from a large dictionary. The dictionary is constructed by merging and intersecting segments obtained from multiple bottom-up over-segmentations. The linear program is solved efficiently using dual decomposition. In the context of parameter estimation, the main problem we face is the lack of fully supervised data. We address this issue by developing a principled framework for parameter estimation using diverse data. More precisely, we propose a latent structural support vector machine formulation, where the latent variables model any missing information in the human annotation. Of particular interest to us are three types of annotations: (i) images segmented using generic foreground or background classes; (ii) images with bounding boxes specified for objects; and (iii) images labeled to indicate the presence of a class. Using large, publicly available datasets we show that our methods are able to significantly improve the accuracy of the region-based model.

  14. Universal geometrical factor of protein conformations as a consequence of energy minimization

    CERN Document Server

    Wu, Ming-Chya; Ma, Wen-Jong; Kouza, Maksim; Hu, Chin-Kun; 10.1209/0295-5075/96/68005

    2012-01-01

    The biological activity and functional specificity of proteins depend on their native three-dimensional structures determined by inter- and intra-molecular interactions. In this paper, we investigate the geometrical factor of protein conformation as a consequence of energy minimization in protein folding. Folding simulations of 10 polypeptides with chain length ranging from 183 to 548 residues manifest that the dimensionless ratio (V/(A)) of the van der Waals volume V to the surface area A and average atomic radius of the folded structures, calculated with atomic radii setting used in SMMP [Eisenmenger F., et. al., Comput. Phys. Commun., 138 (2001) 192], approach 0.49 quickly during the course of energy minimization. A large scale analysis of protein structures show that the ratio for real and well-designed proteins is universal and equal to 0.491\\pm0.005. The fractional composition of hydrophobic and hydrophilic residues does not affect the ratio substantially. The ratio also holds for intrinsically disorde...

  15. Elucidating molecular motion through structural and dynamic filters of energy-minimized conformer ensembles.

    Science.gov (United States)

    Emani, Prashant S; Bardaro, Michael F; Huang, Wei; Aragon, Sergio; Varani, Gabriele; Drobny, Gary P

    2014-02-20

    Complex RNA structures are constructed from helical segments connected by flexible loops that move spontaneously and in response to binding of small molecule ligands and proteins. Understanding the conformational variability of RNA requires the characterization of the coupled time evolution of interconnected flexible domains. To elucidate the collective molecular motions and explore the conformational landscape of the HIV-1 TAR RNA, we describe a new methodology that utilizes energy-minimized structures generated by the program "Fragment Assembly of RNA with Full-Atom Refinement (FARFAR)". We apply structural filters in the form of experimental residual dipolar couplings (RDCs) to select a subset of discrete energy-minimized conformers and carry out principal component analyses (PCA) to corroborate the choice of the filtered subset. We use this subset of structures to calculate solution T1 and T(1ρ) relaxation times for (13)C spins in multiple residues in different domains of the molecule using two simulation protocols that we previously published. We match the experimental T1 times to within 2% and the T(1ρ) times to within less than 10% for helical residues. These results introduce a protocol to construct viable dynamic trajectories for RNA molecules that accord well with experimental NMR data and support the notion that the motions of the helical portions of this small RNA can be described by a relatively small number of discrete conformations exchanging over time scales longer than 1 μs.

  16. Energy-efficient approach to minimizing the energy consumption in an extended job-shop scheduling problem

    Science.gov (United States)

    Tang, Dunbing; Dai, Min

    2015-09-01

    The traditional production planning and scheduling problems consider performance indicators like time, cost and quality as optimization objectives in manufacturing processes. However, environmentally-friendly factors like energy consumption of production have not been completely taken into consideration. Against this background, this paper addresses an approach to modify a given schedule generated by a production planning and scheduling system in a job shop floor, where machine tools can work at different cutting speeds. It can adjust the cutting speeds of the operations while keeping the original assignment and processing sequence of operations of each job fixed in order to obtain energy savings. First, the proposed approach, based on a mixed integer programming mathematical model, changes the total idle time of the given schedule to minimize energy consumption in the job shop floor while accepting the optimal solution of the scheduling objective, makespan. Then, a genetic-simulated annealing algorithm is used to explore the optimal solution due to the fact that the problem is strongly NP-hard. Finally, the effectiveness of the approach is performed smalland large-size instances, respectively. The experimental results show that the approach can save 5%-10% of the average energy consumption while accepting the optimal solution of the makespan in small-size instances. In addition, the average maximum energy saving ratio can reach to 13%. And it can save approximately 1%-4% of the average energy consumption and approximately 2.4% of the average maximum energy while accepting the near-optimal solution of the makespan in large-size instances. The proposed research provides an interesting point to explore an energy-aware schedule optimization for a traditional production planning and scheduling problem.

  17. Non-minimal Derivative Coupling Scalar Field Reconstruction of Bulk Viscous Dark Energy

    CERN Document Server

    Mostaghel, Behrang; Movahed, S M S

    2016-01-01

    Inspired by thermodynamical dissipative phenomena, we consider constant bulk viscosity for dark fluid in a spatially flat two-component Universe. Our viscous dark energy model represents Phantom crossing avoiding Big-Rip singularity. We propose a non-minimal derivative coupling scalar field with zero potential to describe viscous dark energy model. In this approach, coupling constant ($\\kappa$) is related to viscosity coefficient ($\\gamma$) and energy density of dark energy at the present time ($\\Omega_{\\rm DE}^0$). This coupling is bounded as $\\kappa\\in [-1/9H_0^2(1-\\Omega_{\\rm DE}^0), 0]$ and for $\\gamma=0$ leads to $\\kappa=0$. To perform robust analysis, we implement recent observational data sets including Joint Light-curve Analysis (JLA) for SNIa, Gamma Ray Bursts (GRBs) for most luminous astrophysical objects at high redshifts, Baryon Acoustic Oscillations (BAO) from different surveys, Hubble parameter from HST project, {\\it Planck} data for CMB power spectrum and CMB Lensing. Joint analysis of JLA$+$GR...

  18. Mass minimization of a discrete regenerative fuel cell (RFC) system for on-board energy storage

    Science.gov (United States)

    Li, Xiaojin; Xiao, Yu; Shao, Zhigang; Yi, Baolian

    RFC combined with solar photovoltaic (PV) array is the advanced technologic solution for on-board energy storage, e.g. land, sky, stratosphere and aerospace applications, due to its potential of achieving high specific energy. This paper focuses on mass modeling and calculation for a RFC system consisting of discrete electrochemical cell stacks (fuel cell and electrolyzer), together with fuel storage, a PV array, and a radiator. A nonlinear constrained optimization procedure is used to minimize the entire system mass, as well as to study the effect of operating conditions (e.g. current densities of fuel cell and electrolyzer) on the system mass. According to the state-of-the-art specific power of both electrochemical stacks, an energy storage system has been designed for the conditions of stratosphere applications and a rated power output of 12 kW. The calculation results show that the optimization of the current density of both stacks is of importance in designing the light weight on-board energy system.

  19. Optimum fuel loads in migratory birds: distinguishing between time and energy minimization

    Science.gov (United States)

    Hedenstrom; Alerstam

    1997-12-07

    By combining the potential flight range of fuel with different migration policies, the optimum departure fuel load for migratory birds can be calculated. We evaluate the optimum departure fuel loads associated with minimization of three different currencies: (1) overall time of migration, (2) energy cost of transport and (3) total energy coast of migration. Predicted departure loads are highest for (1), lowest for (2) and intermediate for (3). Further, currencies (1) and (3) show departure loads dependent on the fuel accumulation rate at stopovers, while (2) is not affected by variation in the rate of fuel accumulation. Furthermore, fuel loads optimized with respect to currency (3) will differ depending on the size (body mass) of the bird and the energy density of the fuel. We review ecological situations in which the various currencies may apply, and suggest how a combination of stopover decisions and observations of flight speed may be used to decide among the three cases of migration policies. Finally, we calculate that the total energy cost of migration is roughly divided between flight and stopover as 1:2. The total time of migration is similarly divided between flight and stopover as 1:7, probably with a relatively longer stopover time in larger species. Hence, we may expect strong selection pressures to optimize the fuel accumulation strategies during stopover episodes.Copyright 1997 Academic Press Limited Copyright 1997 Academic Press Limited

  20. Energy spread minimization in a cascaded laser wakefield accelerator via velocity bunching

    Science.gov (United States)

    Zhang, Zhijun; Li, Wentao; Liu, Jiansheng; Wang, Wentao; Yu, Changhai; Tian, Ye; Nakajima, Kazuhisa; Deng, Aihua; Qi, Rong; Wang, Cheng; Qin, Zhiyong; Fang, Ming; Liu, Jiaqi; Xia, Changquan; Li, Ruxin; Xu, Zhizhan

    2016-05-01

    We propose a scheme to minimize the energy spread of an electron beam (e-beam) in a cascaded laser wakefield accelerator to the one-thousandth-level by inserting a stage to compress its longitudinal spatial distribution. In this scheme, three-segment plasma stages are designed for electron injection, e-beam length compression, and e-beam acceleration, respectively. The trapped e-beam in the injection stage is transferred to the zero-phase region at the center of one wakefield period in the compression stage where the length of the e-beam can be greatly shortened owing to the velocity bunching. After being seeded into the third stage for acceleration, the e-beam can be accelerated to a much higher energy before its energy chirp is compensated owing to the shortened e-beam length. A one-dimensional theory and two-dimensional particle-in-cell simulations have demonstrated this scheme and an e-beam with 0.2% rms energy spread and low transverse emittance could be generated without loss of charge.

  1. Hack's relation and optimal channel networks: The elongation of river basins as a consequence of energy minimization

    Science.gov (United States)

    Ijjasz-Vasquez, Ede J.; Bras, Rafael L.; Rodriguez-Iturbe, Ignacio

    1993-08-01

    As pointed by Hack (1957), river basins tend to become longer and narrower as their size increases. This work shows that this property may be partially regarded as the consequence of competition and minimization of energy expenditure in river basins.

  2. Crystal engineering on industrial diaryl pigments using lattice energy minimizations and X-ray powder diffraction.

    Science.gov (United States)

    Schmidt, Martin U; Dinnebier, Robert E; Kalkhof, Holger

    2007-08-23

    Diaryl azo pigments play an important role as yellow pigments for printing inks, with an annual pigment production of more than 50,000 t. The crystal structures of Pigment Yellow 12 (PY12), Pigment Yellow 13 (PY13), Pigment Yellow 14 (PY14), and Pigment Yellow 83 (PY83) were determined from X-ray powder data using lattice energy minimizations and subsequent Rietveld refinements. Details of the lattice energy minimization procedure and of the development of a torsion potential for the biphenyl fragment are given. The Rietveld refinements were carried out using rigid bodies, or constraints. It was also possible to refine all atomic positions individually without any constraint or restraint, even for PY12 having 44 independent non-hydrogen atoms per asymmetric unit. For PY14 (23 independent non-hydrogen atoms), additionally all atomic isotropic temperature factors could be refined individually. PY12 crystallized in a herringbone arrangement with twisted biaryl fragments. PY13 and PY14 formed a layer structure of planar molecules. PY83 showed a herringbone structure with planar molecules. According to quantum mechanical calculations, the twisting of the biaryl fragment results in a lower color strength of the pigments, whereas changes in the substitution pattern have almost no influence on the color strength of a single molecule. Hence, the experimentally observed lower color strength of PY12 in comparison with that of PY13 and PY83 can be explained as a pure packing effect. Further lattice energy calculations explained that the four investigated pigments crystallize in three different structures because these structures are the energetically most favorable ones for each compound. For example, for PY13, PY14, or PY83, a PY12-analogous crystal structure would lead to considerably poorer lattice energies and lower densities. In contrast, lattice energy calculations revealed that PY12 could adopt a PY13-type structure with only slightly poorer energy. This structure was

  3. Crystal Engineering on Industrial Diaryl Pigments Using Lattice Energy Minimizations and X-ray Powder Diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Schmidt,M.; Dinnebier, R.; Kalkhof, H.

    2007-01-01

    Diaryl azo pigments play an important role as yellow pigments for printing inks, with an annual pigment production of more than 50,000 t. The crystal structures of Pigment Yellow 12 (PY12), Pigment Yellow 13 (PY13), Pigment Yellow 14 (PY14), and Pigment Yellow 83 (PY83) were determined from X-ray powder data using lattice energy minimizations and subsequent Rietveld refinements. Details of the lattice energy minimization procedure and of the development of a torsion potential for the biphenyl fragment are given. The Rietveld refinements were carried out using rigid bodies, or constraints. It was also possible to refine all atomic positions individually without any constraint or restraint, even for PY12 having 44 independent non-hydrogen atoms per asymmetric unit. For PY14 (23 independent non-hydrogen atoms), additionally all atomic isotropic temperature factors could be refined individually. PY12 crystallized in a herringbone arrangement with twisted biaryl fragments. PY13 and PY14 formed a layer structure of planar molecules. PY83 showed a herringbone structure with planar molecules. According to quantum mechanical calculations, the twisting of the biaryl fragment results in a lower color strength of the pigments, whereas changes in the substitution pattern have almost no influence on the color strength of a single molecule. Hence, the experimentally observed lower color strength of PY12 in comparison with that of PY13 and PY83 can be explained as a pure packing effect. Further lattice energy calculations explained that the four investigated pigments crystallize in three different structures because these structures are the energetically most favorable ones for each compound. For example, for PY13, PY14, or PY83, a PY12-analogous crystal structure would lead to considerably poorer lattice energies and lower densities. In contrast, lattice energy calculations revealed that PY12 could adopt a PY13-type structure with only slightly poorer energy. This structure was

  4. Constraints on B and Higgs physics in minimal low energy supersymmetric models

    Energy Technology Data Exchange (ETDEWEB)

    Carena, Marcela; /Fermilab; Menon, A.; /Argonne /Chicago U., EFI; Noriega-Papaqui, R.; /Fermilab /Puebla U., Inst. Fis.; Szynkman, A.; /Fermilab /Montreal U. /La Plata U.; Wagner, C.E.M.; /Argonne /Chicago U., EFI

    2006-03-01

    We study the implications of minimal flavor violating low energy supersymmetry scenarios for the search of new physics in the B and Higgs sectors at the Tevatron collider and the LHC. We show that the already stringent Tevatron bound on the decay rate B{sub s} {yields} {mu}{sup +}{mu}{sup -} sets strong constraints on the possibility of generating large corrections to the mass difference {Delta} M{sub s} of the B{sub s} eigenstates. We also show that the B{sub s} {yields} {mu}{sup +}{mu}{sup -} bound together with the constraint on the branching ratio of the rare decay b {yields} s{gamma} has strong implications for the search of light, non-standard Higgs bosons at hadron colliders. In doing this, we demonstrate that the former expressions derived for the analysis of the double penguin contributions in the Kaon sector need to be corrected by additional terms for a realistic analysis of these effects. We also study a specific non-minimal flavor violating scenario, where there are flavor changing gluino-squark-quark interactions, governed by the CKM matrix elements, and show that the B and Higgs physics constraints are similar to the ones in the minimal flavor violating case. Finally we show that, in scenarios like electroweak baryogenesis which have light stops and charginos, there may be enhanced effects on the B and K mixing parameters, without any significant effect on the rate of B{sub s} {yields} {mu}{sup +}{mu}{sup -}.

  5. Reduction efficiency prediction of CENIBRA's recovery boiler by direct minimization of gibbs free energy

    Directory of Open Access Journals (Sweden)

    W. L. Silva

    2008-09-01

    Full Text Available The reduction efficiency is an important variable during the black liquor burning process in the Kraft recovery boiler. This variable value is obtained by slow experimental routines and the delay of this measure disturbs the pulp and paper industry customary control. This paper describes an optimization approach for the reduction efficiency determination in the furnace bottom of the recovery boiler based on the minimization of the Gibbs free energy. The industrial data used in this study were directly obtained from CENIBRA's data acquisition system. The resulting approach is able to predict the steady state behavior of the chemical composition of the furnace recovery boiler, - especially the reduction efficiency when different operational conditions are used. This result confirms the potential of this approach in the analysis of the daily operation of the recovery boiler.

  6. High-energy suppression of the Higgsstrahlung cross-section in the Minimal Composite Higgs Model

    CERN Document Server

    Hartling, Katy

    2012-01-01

    If the Higgs boson is composite, signs of this compositeness should appear via a formfactor-like suppression of Higgs scattering cross sections at momentum transfers above the compositeness scale. We explore this by computing the cross section for e+e- ---> ZH (Higgsstrahlung) in a warped five-dimensional gauge-Higgs unification model known as the Minimal Composite Higgs Model (MCHM). We observe that the Higgsstrahlung cross section in the MCHM is strongly suppressed compared to that in the Standard Model at center-of-mass energies above the scale of the first Kaluza-Klein excitations, due to cancellations among the contributions of successive Z boson Kaluza-Klein modes. We also show that the magnitude and sign of the coupling of the first Kaluza-Klein mode can be measured at a future electron-positron collider such as the proposed International Linear Collider or Compact Linear Collider.

  7. Color Correction for Multi-view Video Using Energy Minimization of View Networks

    Institute of Scientific and Technical Information of China (English)

    Kenji Yamamoto; Ryutaro Oi

    2008-01-01

    Systems using numerous cameras are emerging in many fields due to their ease of production and reduced cost, and one of the fields where they are expected to be used more actively in the near future is in image-based rendering (IBR). Color correction between views is necessary to use multi-view systems in IBR to make audiences feel comfortable when views are switched or when a free viewpoint video is displayed. Color correction usually involves two steps: the first is to adjust camera parameters such as gain, brightness, and aperture before capture, and the second is to modify captured videos through image processing. This paper deals with the latter, which does not need a color pattern board. The proposed method uses scale invariant feature transform (SIFT) to detect correspondences, treats RGB channels independently, calculates lookup tables with an energy-minimization approach, and corrects captured video with these tables. The experimental results reveal that this approach works well.

  8. Structural differences of matrix metalloproteinases. Homology modeling and energy minimization of enzyme-substrate complexes

    DEFF Research Database (Denmark)

    Terp, G E; Christensen, I T; Jørgensen, Flemming Steen

    2000-01-01

    in the AMBER 4.1 force field, applying a non-bonded approach and a full ion charge representation. Energy minimization of the apoenzymes yielded structures with distorted active sites, while reliable three-dimensional structures of the enzymes containing a substrate in active site were obtained. The structural...... differences between the eight enzyme-substrate complexes were studied with particular emphasis on the active site, and possible sites for obtaining selectivity among the MMP's are discussed. Differences in the P1' pocket are well-documented and have been extensively exploited in inhibitor design. The present......Matrix metalloproteinases are extracellular enzymes taking part in the remodeling of extracellular matrix. The structures of the catalytic domain of MMP1, MMP3, MMP7 and MMP8 are known, but structures of enzymes belonging to this family still remain to be determined. A general approach...

  9. High Performance Imaging Through Occlusion via Energy Minimization-Based Optimal Camera Selection

    Directory of Open Access Journals (Sweden)

    Tao Yang

    2013-11-01

    Full Text Available Seeing an object in a cluttered scene with severe occlusion is a significantly challenging task for many computer vision applications. Although camera array synthetic aperture imaging has proven to be an effective way for occluded object imaging, its imaging quality is often significantly decreased by the shadows of the foreground occluder. To overcome this problem, some recent research has been presented to label the foreground occluder via object segmentation or 3D reconstruction. However, these methods usually fail in the case of complicated occluder or severe occlusion. In this paper, we present a novel optimal camera selection algorithm to handle the problem above. Firstly, in contrast to the traditional synthetic aperture photography methods, we formulate the occluded object imaging as a problem of visible light ray selection from the optimal camera view. To the best of our knowledge, this is the first time to "mosaic" a high quality occluded object image via selecting multi-view optimal visible light rays from a camera array or a single moving camera. Secondly, a greedy optimization framework is presented to propagate the visibility information among various depth focus planes. Thirdly, a multiple label energy minimization formulation is designed in each plane to select the optimal camera view. The energy is estimated in the 3D synthetic aperture image volume and integrates the multiple view intensity consistency, previous visibility property and camera view smoothness, which is minimized via graph cuts. Finally, we compare this approach with the traditional synthetic aperture imaging algorithms on UCSD light field datasets and our own datasets captured in indoor and outdoor environment, and extensive experimental results demonstrate the effectiveness and superiority of our approach.

  10. The synergy between protein positioning and DNA elasticity: energy minimization of protein-decorated DNA minicircles

    CERN Document Server

    Clauvelin, Nicolas

    2014-01-01

    The binding of proteins onto DNA contributes to the shaping and packaging of genome as well as to the expression of specific genetic messages. With a view to understanding the interplay between the presence of proteins and the deformation of DNA involved in such processes, we developed a new method to minimize the elastic energy of DNA fragments at the mesoscale level. Our method makes it possible to obtain the optimal pathways of protein-decorated DNA molecules for which the terminal base pairs are spatially constrained. We focus in this work on the deformations induced by selected architectural proteins on circular DNA. We report the energy landscapes of DNA minicircles subjected to different levels of torsional stress and containing one or two proteins as functions of the chain length and spacing between the proteins. Our results reveal cooperation between the elasticity of the double helix and the structural distortions of DNA induced by bound proteins. We find that the imposed mechanical stress influence...

  11. Maximizing cellulosic ethanol potentials by minimizing wastewater generation and energy consumption: Competing with corn ethanol.

    Science.gov (United States)

    Liu, Gang; Bao, Jie

    2017-08-21

    Energy consumption and wastewater generation in cellulosic ethanol production are among the determinant factors on overall cost and technology penetration into fuel ethanol industry. This study analyzed the energy consumption and wastewater generation by the new biorefining process technology, dry acid pretreatment and biodetoxification (DryPB), as well as by the current mainstream technologies. DryPB minimizes the steam consumption to 8.63GJ and wastewater generation to 7.71tons in the core steps of biorefining process for production of one metric ton of ethanol, close to 7.83GJ and 8.33tons in corn ethanol production, respectively. The relatively higher electricity consumption is compensated by large electricity surplus from lignin residue combustion. The minimum ethanol selling price (MESP) by DryPB is below $2/gal and falls into the range of corn ethanol production cost. The work indicates that the technical and economical gap between cellulosic ethanol and corn ethanol has been almost filled up. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Quasi-uniformity of Minimal Weighted Energy Points on Compact Metric Spaces

    CERN Document Server

    Hardin, D P; Whitehouse, J T

    2011-01-01

    For a closed subset $K$ of a compact metric space $A$ possessing an $\\alpha$-regular measure $\\mu$ with $\\mu(K)>0$, we prove that whenever $s>\\alpha$, any sequence of weighted minimal Riesz $s$-energy configurations $\\omega_N=\\{x_{i,N}^{(s)}\\}_{i=1}^N$ on $K$ (for `nice' weights) is quasi-uniform in the sense that the ratios of its mesh norm to separation distance remain bounded as $N$ grows large. Furthermore, if $K$ is an $\\alpha$-rectifiable compact subset of Euclidean space with positive and finite $\\alpha$-dimensional Hausdorff measure, it is possible to generate such a quasi-uniform sequence of configurations that also has (as $N\\to \\infty$) a prescribed positive continuous limit distribution with respect to $\\alpha$-dimensional Hausdorff measure. As a consequence of our energy related results for the unweighted case, we deduce that if $A$ is a compact $C^1$ manifold, then there exists a sequence of $N$-point best-packing configurations on $A$ whose mesh-separation ratios have limit superior (as $N\\to \\...

  13. A Two-stage Optimal Network Reconfiguration Approach for Minimizing Energy Loss of Distribution Networks Using Particle Swarm Optimization Algorithm

    Directory of Open Access Journals (Sweden)

    Wei-Tzer Huang

    2015-12-01

    Full Text Available This study aimed to minimize energy losses in traditional distribution networks and microgrids through a network reconfiguration and phase balancing approach. To address this problem, an algorithm composed of a multi-objective function and operation constraints is proposed. Network connection matrices based on graph theory and the backward/forward sweep method are used to analyze power flow. A minimizing energy loss approach is developed for network reconfiguration and phase balancing, and the particle swarm optimization (PSO algorithm is adopted to solve this optimal combination problem. The proposed approach is tested on the IEEE 37-bus test system and the first outdoor microgrid test bed established by the Institute of Nuclear Energy Research (INER in Taiwan. Simulation results demonstrate that the proposed two-stage approach can be applied in network reconfiguration to minimize energy loss.

  14. [Possible changes in energy-minimizer mechanisms of locomotion due to chronic low back pain - a literature review].

    Science.gov (United States)

    de Carvalho, Alberito Rodrigo; Andrade, Alexandro; Peyré-Tartaruga, Leonardo Alexandre

    2015-01-01

    One goal of the locomotion is to move the body in the space at the most economical way possible. However, little is known about the mechanical and energetic aspects of locomotion that are affected by low back pain. And in case of occurring some damage, little is known about how the mechanical and energetic characteristics of the locomotion are manifested in functional activities, especially with respect to the energy-minimizer mechanisms during locomotion. This study aimed: a) to describe the main energy-minimizer mechanisms of locomotion; b) to check if there are signs of damage on the mechanical and energetic characteristics of the locomotion due to chronic low back pain (CLBP) which may endanger the energy-minimizer mechanisms. This study is characterized as a narrative literature review. The main theory that explains the minimization of energy expenditure during the locomotion is the inverted pendulum mechanism, by which the energy-minimizer mechanism converts kinetic energy into potential energy of the center of mass and vice-versa during the step. This mechanism is strongly influenced by spatio-temporal gait (locomotion) parameters such as step length and preferred walking speed, which, in turn, may be severely altered in patients with chronic low back pain. However, much remains to be understood about the effects of chronic low back pain on the individual's ability to practice an economic locomotion, because functional impairment may compromise the mechanical and energetic characteristics of this type of gait, making it more costly. Thus, there are indications that such changes may compromise the functional energy-minimizer mechanisms. Copyright © 2014 Elsevier Editora Ltda. All rights reserved.

  15. Optimal replacement of residential air conditioning equipment to minimize energy, greenhouse gas emissions, and consumer cost in the US

    Energy Technology Data Exchange (ETDEWEB)

    De Kleine, Robert D. [Center for Sustainable Systems, School of Natural Resources and Environment, University of Michigan, 440 Church St., Dana Bldg., Ann Arbor, MI 48109-1041 (United States); Keoleian, Gregory A., E-mail: gregak@umich.edu [Center for Sustainable Systems, School of Natural Resources and Environment, University of Michigan, 440 Church St., Dana Bldg., Ann Arbor, MI 48109-1041 (United States); Kelly, Jarod C. [Center for Sustainable Systems, School of Natural Resources and Environment, University of Michigan, 440 Church St., Dana Bldg., Ann Arbor, MI 48109-1041 (United States)

    2011-06-15

    A life cycle optimization of the replacement of residential central air conditioners (CACs) was conducted in order to identify replacement schedules that minimized three separate objectives: life cycle energy consumption, greenhouse gas (GHG) emissions, and consumer cost. The analysis was conducted for the time period of 1985-2025 for Ann Arbor, MI and San Antonio, TX. Using annual sales-weighted efficiencies of residential CAC equipment, the tradeoff between potential operational savings and the burdens of producing new, more efficient equipment was evaluated. The optimal replacement schedule for each objective was identified for each location and service scenario. In general, minimizing energy consumption required frequent replacement (4-12 replacements), minimizing GHG required fewer replacements (2-5 replacements), and minimizing cost required the fewest replacements (1-3 replacements) over the time horizon. Scenario analysis of different federal efficiency standards, regional standards, and Energy Star purchases were conducted to quantify each policy's impact. For example, a 16 SEER regional standard in Texas was shown to either reduce primary energy consumption 13%, GHGs emissions by 11%, or cost by 6-7% when performing optimal replacement of CACs from 2005 or before. The results also indicate that proper servicing should be a higher priority than optimal replacement to minimize environmental burdens. - Highlights: > Optimal replacement schedules for residential central air conditioners were found. > Minimizing energy required more frequent replacement than minimizing consumer cost. > Significant variation in optimal replacement was observed for Michigan and Texas. > Rebates for altering replacement patterns are not cost effective for GHG abatement. > Maintenance levels were significant in determining the energy and GHG impacts.

  16. Quantum electrodynamics and the electron self-energy in a deformed space with a minimal length scale

    CERN Document Server

    Silva, Apollo V; Neves, M J

    2016-01-01

    The main motivation to study models in the presence of a minimal length is to obtain a quantum field theory free of the divergences. In this way, in this paper, we have constructed a new framework for quantum electrodynamics embedded in a minimal length scale background. New operators are introduced and the Green function method was used for the solution of the field equations, i.e., the Maxwell, Klein-Gordon and Dirac equations. We have analyzed specifically the scalar field and its one loop propagator. The mass of the scalar field regularized by the minimal length was obtained. The QED Lagrangian containing a minimal length was also constructed and the divergences were analyzed. The electron and photon propagators, and the electron self-energy at one loop as a function of the minimal length was also obtained.

  17. Evaluation of the suitability of free-energy minimization using nearest-neighbor energy parameters for RNA secondary structure prediction

    Directory of Open Access Journals (Sweden)

    Cobaugh Christian W

    2004-08-01

    Full Text Available Abstract Background A detailed understanding of an RNA's correct secondary and tertiary structure is crucial to understanding its function and mechanism in the cell. Free energy minimization with energy parameters based on the nearest-neighbor model and comparative analysis are the primary methods for predicting an RNA's secondary structure from its sequence. Version 3.1 of Mfold has been available since 1999. This version contains an expanded sequence dependence of energy parameters and the ability to incorporate coaxial stacking into free energy calculations. We test Mfold 3.1 by performing the largest and most phylogenetically diverse comparison of rRNA and tRNA structures predicted by comparative analysis and Mfold, and we use the results of our tests on 16S and 23S rRNA sequences to assess the improvement between Mfold 2.3 and Mfold 3.1. Results The average prediction accuracy for a 16S or 23S rRNA sequence with Mfold 3.1 is 41%, while the prediction accuracies for the majority of 16S and 23S rRNA structures tested are between 20% and 60%, with some having less than 20% prediction accuracy. The average prediction accuracy was 71% for 5S rRNA and 69% for tRNA. The majority of the 5S rRNA and tRNA sequences have prediction accuracies greater than 60%. The prediction accuracy of 16S rRNA base-pairs decreases exponentially as the number of nucleotides intervening between the 5' and 3' halves of the base-pair increases. Conclusion Our analysis indicates that the current set of nearest-neighbor energy parameters in conjunction with the Mfold folding algorithm are unable to consistently and reliably predict an RNA's correct secondary structure. For 16S or 23S rRNA structure prediction, Mfold 3.1 offers little improvement over Mfold 2.3. However, the nearest-neighbor energy parameters do work well for shorter RNA sequences such as tRNA or 5S rRNA, or for larger rRNAs when the contact distance between the base-pairs is less than 100 nucleotides.

  18. A new extension algorithm for cubic B-splines based on minimal strain energy

    Institute of Scientific and Technical Information of China (English)

    MO Guo-liang; ZHAO Ya-nan

    2006-01-01

    Extension ora B-spline curve or surface is a useful function in a CAD system. This paper presents an algorithm for extending cubic B-spline curves or surfaces to one or more target points. To keep the extension curve segment GC2-continuous with the original one, a family of cubic polynomial interpolation curves can be constructed. One curve is chosen as the solution from a sub-class of such a family by setting one GC2 parameter to be zero and determining the second GC2 parameter by minimizing the strain energy. To simplify the final curve representation, the extension segment is reparameterized to achieve C2-continuity with the given B-spline curve, and then knot removal from the curve is done. As a result, a sub-optimized solution subject to the given constraints and criteria is obtained. Additionally, new control points of the extension B-spline segment can be determined by solving lower triangular linear equations. Some computing examples for comparing our method and other methods are given.

  19. Application of free energy minimization to the design of adaptive multi-agent teams

    Science.gov (United States)

    Levchuk, Georgiy; Pattipati, Krishna; Fouse, Adam; Serfaty, Daniel

    2017-05-01

    Many novel DoD missions, from disaster relief to cyber reconnaissance, require teams of humans and machines with diverse capabilities. Current solutions do not account for heterogeneity of agent capabilities, uncertainty of team knowledge, and dynamics of and dependencies between tasks and agent roles, resulting in brittle teams. Most importantly, the state-of-the-art team design solutions are either centralized, imposing role and relation assignment onto agents, or completely distributed, suitable for only homogeneous organizations such as swarms. Centralized design models can't provide insights for team's self-organization, i.e. adapting team structure over time in distributed collaborative manner by team members with diverse expertise and responsibilities. In this paper we present an information-theoretic formalization of team composition and structure adaptation using a minimization of variational free energy. The structure adaptation is obtained in an iterative distributed and collaborative manner without the need for centralized control. We show that our model is lightweight, predictive, and produces team structures that theoretically approximate an optimal policy for team adaptation. Our model also provides a unique coupling between the structure and action policy, and captures three essential processes of learning, perception, and control.

  20. Alternating minimal energy approach to ODEs and conservation laws in tensor product formats

    CERN Document Server

    Dolgov, Sergey V

    2014-01-01

    We propose an algorithm for solution of high-dimensional evolutionary equations (ODEs and discretized time-dependent PDEs) in tensor product formats. The solution must admit an approximation in a low-rank separation of variables framework, and the right-hand side of the ODE (for example, a matrix) must be computable in the same low-rank format at a given time point. The time derivative is discretized via the Chebyshev spectral scheme, and the solution is sought simultaneously for all time points from the global space-time linear system. To compute the solution adaptively in the tensor format, we employ the Alternating Minimal Energy algorithm, the DMRG-flavored alternating iterative technique. Besides, we address the problem of maintaining system invariants inside the approximate tensor product scheme. We show how the conservation of a linear function, defined by a vector given in the low-rank format, or the second norm of the solution may be accurately and elegantly incorporated into the tensor product metho...

  1. Self-organization, free energy minimization, and optimal grip on a field of affordances

    Directory of Open Access Journals (Sweden)

    Jelle eBruineberg

    2014-08-01

    Full Text Available In this paper, we set out to develop a theoretical and conceptual framework for the new field of Radical Embodied Cognitive Neuroscience. This framework should be able to integrate insights from several relevant disciplines: theory on embodied cognition, ecological psychology, phenomenology, dynamical systems theory, and neurodynamics. We suggest that the main task of Radical Embodied Cognitive Neuroscience is to investigate the phenomenon of skilled intentionality from the perspective of the self-organization of the brain-body-environment system, while doing justice to the phenomenology of skilled action. In previous work, we have characterized skilled intentionality as the organism’s tendency towards an optimal grip on multiple relevant affordances simultaneously. Affordances are possibilities for action provided by the environment. In the first part of this paper, we introduce the notion of skilled intentionality and the phenomenon of responsiveness to a field of relevant affordances. Second, we use Friston’s work on neurodynamics, but embed a very minimal version of his Free Energy Principle in the ecological niche of the animal. Thus amended, this principle is helpful for understanding the embeddedness of neurodynamics within the dynamics of the brain-body-environment system. Next, we show how we can use this adjusted principle to understand the neurodynamics of selective openness to the environment: interacting action-readiness patterns at multiple timescales contribute to the organism’s selective openness to relevant affordances. In the final part of the paper, we emphasize the important role of metastable dynamics in both the brain and the brain-body-environment system for adequate affordance-responsiveness. We exemplify our integrative approach by presenting research on the impact of Deep Brain Stimulation on affordance responsiveness of OCD patients.

  2. Self-organization, free energy minimization, and optimal grip on a field of affordances.

    Science.gov (United States)

    Bruineberg, Jelle; Rietveld, Erik

    2014-01-01

    In this paper, we set out to develop a theoretical and conceptual framework for the new field of Radical Embodied Cognitive Neuroscience. This framework should be able to integrate insights from several relevant disciplines: theory on embodied cognition, ecological psychology, phenomenology, dynamical systems theory, and neurodynamics. We suggest that the main task of Radical Embodied Cognitive Neuroscience is to investigate the phenomenon of skilled intentionality from the perspective of the self-organization of the brain-body-environment system, while doing justice to the phenomenology of skilled action. In previous work, we have characterized skilled intentionality as the organism's tendency toward an optimal grip on multiple relevant affordances simultaneously. Affordances are possibilities for action provided by the environment. In the first part of this paper, we introduce the notion of skilled intentionality and the phenomenon of responsiveness to a field of relevant affordances. Second, we use Friston's work on neurodynamics, but embed a very minimal version of his Free Energy Principle in the ecological niche of the animal. Thus amended, this principle is helpful for understanding the embeddedness of neurodynamics within the dynamics of the system "brain-body-landscape of affordances." Next, we show how we can use this adjusted principle to understand the neurodynamics of selective openness to the environment: interacting action-readiness patterns at multiple timescales contribute to the organism's selective openness to relevant affordances. In the final part of the paper, we emphasize the important role of metastable dynamics in both the brain and the brain-body-environment system for adequate affordance-responsiveness. We exemplify our integrative approach by presenting research on the impact of Deep Brain Stimulation on affordance responsiveness of OCD patients.

  3. A bi-objective model for job-shop scheduling problem to minimize both energy consumption and makespan

    Institute of Scientific and Technical Information of China (English)

    HE Yan; LIU Fei; CAO Hua-jun; LI Cong-bo

    2005-01-01

    The issue of reducing energy consumption for the job-shop scheduling problem in machining systems is addressed, whose dual objectives are to minimize both the energy consumption and the makespan. First, the biobjective model for the job-shop scheduling problem is proposed. The objective function value of the model represents synthesized optimization of energy consumption and makespan. Then, a heuristic algorithm is developed to locate the optimal or near optimal solutions of the model based on the Tabu search mechanism. Finally, the experimental case is presented to demonstrate the effectiveness of the proposed model and the algorithm.

  4. Minimal Model of Quantum Kinetic Clusters for the Energy-Transfer Network of a Light-Harvesting Protein Complex.

    Science.gov (United States)

    Wu, Jianlan; Tang, Zhoufei; Gong, Zhihao; Cao, Jianshu; Mukamel, Shaul

    2015-04-02

    The energy absorbed in a light-harvesting protein complex is often transferred collectively through aggregated chromophore clusters. For population evolution of chromophores, the time-integrated effective rate matrix allows us to construct quantum kinetic clusters quantitatively and determine the reduced cluster-cluster transfer rates systematically, thus defining a minimal model of energy-transfer kinetics. For Fenna-Matthews-Olson (FMO) and light-havrvesting complex II (LCHII) monomers, quantum Markovian kinetics of clusters can accurately reproduce the overall energy-transfer process in the long-time scale. The dominant energy-transfer pathways are identified in the picture of aggregated clusters. The chromophores distributed extensively in various clusters can assist a fast and long-range energy transfer.

  5. Minimality and Local State Decompositions of a Nonlinear State Space Realization Using Energy Functions

    NARCIS (Netherlands)

    Scherpen, Jacquelien M.A.; Gray, W. Steven

    2000-01-01

    In this paper a set of sufficient conditions is developed in terms of controllability and observability functions under which a given state-space realization of a formal power series is minimal. Specifically, it is shown that positivity of these functions, in addition to a stability requirement and

  6. A non-minimally coupled potential for inflation and dark energy after Planck 2015: a comprehensive study

    Science.gov (United States)

    Eshaghi, Mehdi; Zarei, Moslem; Riazi, Nematollah; Kiasatpour, Ahmad

    2015-11-01

    In this work we introduce a new plateau-like inflationary model including a quadratic scalar potential coupled non-minimally to gravity. This potential has a dominant constant energy density at early times which can realize successful inflation. It also includes an infinitesimal non-zero term V0 responsible for explaining dark energy which causing the universe to expand accelerating at the late time. We show that this model predicts small tensor-to-scalar ratio of the order of r≈ 0.01 which is fully consistent with Planck constraints. Using the lower and upper bounds on reheating temperature, we provide additional constraints on the non-minimal coupling parameter ξ of the model. We also study the preheating stage predicted by this kind of potentials using numerical calculations.

  7. A minimal width of the arrival direction distribution of ultra-high energy cosmic rays detected with the Yakutsk array

    CERN Document Server

    Ivanov, A A

    2015-01-01

    This paper presents the results of searches for anisotropy in arrival directions of ultra-high energy cosmic rays detected with the Yakutsk Array during the 1974--2008 observational period together with available data from other giant extensive air shower arrays working at present. A method of analysis based on a comparison of the minimal width of distributions in equatorial coordinates is applied. As a result, a hypothesis of isotropy in arrival directions is rejected at the $99.5\\%$ significance level. The observed decrease in the minimal width of distribution can be explained by the presence of cosmic ray sources in energy intervals and sky regions according to the recent indications inferred from data of the Yakutsk Array and Telescope Array experiments.

  8. Strategic planning for minimizing CO2 emissions using LP model based on forecasted energy demand by PSO Algorithm and ANN

    Directory of Open Access Journals (Sweden)

    M. Yousefi, M. Omid, Sh. Rafiee, S.F. Ghaderi

    2013-01-01

    Full Text Available Iran's primary energy consumption (PEC was modeled as a linear function of five socioeconomic and meteorological explanatory variables using particle swarm optimization (PSO and artificial neural networks (ANNs techniques. Results revealed that ANN outperforms PSO model to predict test data. However, PSO technique is simple and provided us with a closed form expression to forecast PEC. Energy demand was forecasted by PSO and ANN using represented scenario. Finally, adapting about 10% renewable energy revealed that based on the developed linear programming (LP model under minimum CO2 emissions, Iran will emit about 2520 million metric tons CO2 in 2025. The LP model indicated that maximum possible development of hydropower, geothermal and wind energy resources will satisfy the aim of minimization of CO2 emissions. Therefore, the main strategic policy in order to reduce CO2 emissions would be exploitation of these resources.

  9. Minimizing the Levelized Cost of Energy in Single-Phase Photovoltaic Systems with an Absolute Active Power Control

    DEFF Research Database (Denmark)

    Yang, Yongheng; Koutroulis, Eftichios; Sangwongwanich, Ariya

    2015-01-01

    Several countries with considerable PhotoVoltaic (PV) installations are facing a challenge of overloading the power infrastructure during peak-power production hours. Regulations have been imposed on the PV systems, where more active power control should be flexibly performed. As an advanced...... control strategy, the Absolute Active Power Control (AAPC) can effectively solve the overloading issues by limiting the maximum possible PV power to a certain level (i.e., the power limitation), and also benefit the inverter reliability. However, its feasibility is challenged by the energy loss....... An increase of the inverter lifetime and a reduction of the energy yield can alter the cost of energy, demanding an optimization of the power limitation. Therefore, aiming at minimizing the Levelized Cost of Energy (LCOE), the power limit is optimized for the AAPC strategy in this paper. The optimization...

  10. Strategic planning for minimizing CO2 emissions using LP model based on forecasted energy demand by PSO Algorithm and ANN

    Energy Technology Data Exchange (ETDEWEB)

    Yousefi, M.; Omid, M.; Rafiee, Sh. [Department of Agricultural Machinery Engineering, University of Tehran, Karaj (Iran, Islamic Republic of); Ghaderi, S.F. [Department of Industrial Engineering, University of Tehran, Tehran (Iran, Islamic Republic of)

    2013-07-01

    Iran's primary energy consumption (PEC) was modeled as a linear function of five socioeconomic and meteorological explanatory variables using particle swarm optimization (PSO) and artificial neural networks (ANNs) techniques. Results revealed that ANN outperforms PSO model to predict test data. However, PSO technique is simple and provided us with a closed form expression to forecast PEC. Energy demand was forecasted by PSO and ANN using represented scenario. Finally, adapting about 10% renewable energy revealed that based on the developed linear programming (LP) model under minimum CO2 emissions, Iran will emit about 2520 million metric tons CO2 in 2025. The LP model indicated that maximum possible development of hydropower, geothermal and wind energy resources will satisfy the aim of minimization of CO2 emissions. Therefore, the main strategic policy in order to reduce CO2 emissions would be exploitation of these resources.

  11. Minimization of Heat Energy Intensity in Food Production Companies Applying Sustainable Industrial Development Methods

    OpenAIRE

    Irina Kliopova; Rasa Lieščinskienė

    2011-01-01

    Lithuanian food and drink sector of industry is characterized by high energy intensity, which is 29% higher than the EU average. At the confectionary plant chosen for the experiment, an environmental impact has been controlled and its maximum managed by creating different procedures to reduce pollution. Assessment of the plant's environmental costs has revealed that the energy costs amount to main part of the environmental ones (up to 55.4%). In recent years several energy efficiency projects...

  12. Minimization of energy and surface roughness of the products machined by milling

    Science.gov (United States)

    Belloufi, A.; Abdelkrim, M.; Bouakba, M.; Rezgui, I.

    2017-08-01

    Metal cutting represents a large portion in the manufacturing industries, which makes this process the largest consumer of energy. Energy consumption is an indirect source of carbon footprint, we know that CO2 emissions come from the production of energy. Therefore high energy consumption requires a large production, which leads to high cost and a large amount of CO2 emissions. At this day, a lot of researches done on the Metal cutting, but the environmental problems of the processes are rarely discussed. The right selection of cutting parameters is an effective method to reduce energy consumption because of the direct relationship between energy consumption and cutting parameters in machining processes. Therefore, one of the objectives of this research is to propose an optimization strategy suitable for machining processes (milling) to achieve the optimum cutting conditions based on the criterion of the energy consumed during the milling. In this paper the problem of energy consumed in milling is solved by an optimization method chosen. The optimization is done according to the different requirements in the process of roughing and finishing under various technological constraints.

  13. IMPROVING THE TRANSMISSION PERFORMANCE BASED ON MINIMIZING ENERGY IN MOBILE ADHOC NETWORKS

    Directory of Open Access Journals (Sweden)

    Gundala Swathi

    2015-06-01

    Full Text Available Networking is collectively no of mobile nodes allocate users to correctly detect a distant environment. These wireless mobile networks want strong but simple, scalable, energy efficient and also self organize routing algorithms. In Mobile technology small quantity of power electronics and less power radio frequency have permit the expansion of small, comparatively economical and less power nodes, are associated in a wireless mobile networkIn this study we proposed method are: energy effectiveness, energetic occurrence zone and multiple hop TRANSMIT, taking into concern between the energy of transmit nodes and distance from the transmit node to the trusted neighbor node, link weight energy utilization and distance are measured as most important constraint for decide on greatest possible path from Zone Head (ZH to the neighbor node. In this we use the different constraints and lessen the quantity of distribution messages during the Transmit node choice point to decrease the energy utilization of the complete network.

  14. Reduced impact logging minimally alters tropical rainforest carbon and energy exchange

    Science.gov (United States)

    Miller, Scott D.; Goulden, Michael L.; Hutyra, Lucy R.; Keller, Michael; Saleska, Scott R.; Wofsy, Steven C.; Figueira, Adelaine Michela Silva; da Rocha, Humberto R.; de Camargo, Plinio B.

    2011-01-01

    We used eddy covariance and ecological measurements to investigate the effects of reduced impact logging (RIL) on an old-growth Amazonian forest. Logging caused small decreases in gross primary production, leaf production, and latent heat flux, which were roughly proportional to canopy loss, and increases in heterotrophic respiration, tree mortality, and wood production. The net effect of RIL was transient, and treatment effects were barely discernable after only 1 y. RIL appears to provide a strategy for managing tropical forest that minimizes the potential risks to climate associated with large changes in carbon and water exchange. PMID:22087005

  15. Reduced impact logging minimally alters tropical rainforest carbon and energy exchange.

    Science.gov (United States)

    Miller, Scott D; Goulden, Michael L; Hutyra, Lucy R; Keller, Michael; Saleska, Scott R; Wofsy, Steven C; Figueira, Adelaine Michela Silva; da Rocha, Humberto R; de Camargo, Plinio B

    2011-11-29

    We used eddy covariance and ecological measurements to investigate the effects of reduced impact logging (RIL) on an old-growth Amazonian forest. Logging caused small decreases in gross primary production, leaf production, and latent heat flux, which were roughly proportional to canopy loss, and increases in heterotrophic respiration, tree mortality, and wood production. The net effect of RIL was transient, and treatment effects were barely discernable after only 1 y. RIL appears to provide a strategy for managing tropical forest that minimizes the potential risks to climate associated with large changes in carbon and water exchange.

  16. Thermal energy storage to minimize cost and improve efficiency of a polygeneration district energy system in a real-time electricity market

    Energy Technology Data Exchange (ETDEWEB)

    Powell, Kody M.; Kim, Jong Suk; Cole, Wesley J.; Kapoor, Kriti; Mojica, Jose L.; Hedengren, John D.; Edgar, Thomas F.

    2016-10-01

    District energy systems can produce low-cost utilities for large energy networks, but can also be a resource for the electric grid by their ability to ramp production or to store thermal energy by responding to real-time market signals. In this work, dynamic optimization exploits the flexibility of thermal energy storage by determining optimal times to store and extract excess energy. This concept is applied to a polygeneration distributed energy system with combined heat and power, district heating, district cooling, and chilled water thermal energy storage. The system is a university campus responsible for meeting the energy needs of tens of thousands of people. The objective for the dynamic optimization problem is to minimize cost over a 24-h period while meeting multiple loads in real time. The paper presents a novel algorithm to solve this dynamic optimization problem with energy storage by decomposing the problem into multiple static mixed-integer nonlinear programming (MINLP) problems. Another innovative feature of this work is the study of a large, complex energy network which includes the interrelations of a wide variety of energy technologies. Results indicate that a cost savings of 16.5% is realized when the system can participate in the wholesale electricity market.

  17. Dynamics of expansion of the Universe in the models with non-minimally coupled dark energy

    CERN Document Server

    Neomenko, R

    2016-01-01

    We consider the dark energy model with barotropic equation of state, which interacts with dark matter through gravitation and another force, causing the energy-momentum exchange between them. Both components are described in approximation of ideal fluids, which are parametrized by density and equation of state parameters. Three types of interactions between dark components are considered: the interaction independent from their densities, the one proportional to density of dark energy and the one proportional to density of dark matter. The equations which describe the expansion dynamics of homogeneous and isotropic Universe and evolution of densities of both components for different values of interaction parameter are obtained on the bases of the general covariant conservation equations and Einstein's ones. For three kinds of interactions we show the existence of the range of values of parameters of dark energy for which the densities of dark components and their sum are negative. We find the conditions of pos...

  18. Some Observations on Optimal Frequency Selection in DVFS-based Energy Consumption Minimization

    CERN Document Server

    Rizvandi, Nikzad Babaii; Zomaya, Albert Y

    2012-01-01

    In recent years, the issue of energy consumption in parallel and distributed computing systems has attracted a great deal of attention. In response to this, many energy-aware scheduling algorithms have been developed primarily using the dynamic voltage-frequency scaling (DVFS) capability which has been incorporated into recent commodity processors. Majority of these algorithms involve two passes: schedule generation and slack reclamation. The former pass involves the redistribution of tasks among DVFS-enabled processors based on a given cost function that includes makespan and energy consumption; and, while the latter pass is typically achieved by executing individual tasks with slacks at a lower processor frequency. In this paper, a new slack reclamation algorithm is proposed by approaching the energy reduction problem from a different angle. Firstly, the problem of task slack reclamation by using combinations of processors' frequencies is formulated. Secondly, several proofs are provided to show that (1) if...

  19. Energy barriers, entropy barriers, and non-Arrhenius behavior in a minimal glassy model.

    Science.gov (United States)

    Du, Xin; Weeks, Eric R

    2016-06-01

    We study glassy dynamics using a simulation of three soft Brownian particles confined to a two-dimensional circular region. If the circular region is large, the disks freely rearrange, but rearrangements are rarer for smaller system sizes. We directly measure a one-dimensional free-energy landscape characterizing the dynamics. This landscape has two local minima corresponding to the two distinct disk configurations, separated by a free-energy barrier that governs the rearrangement rate. We study several different interaction potentials and demonstrate that the free-energy barrier is composed of a potential-energy barrier and an entropic barrier. The heights of both of these barriers depend on temperature and system size, demonstrating how non-Arrhenius behavior can arise close to the glass transition.

  20. Evaluating performance indices of a shopping centre and implementing HVAC control principles to minimize energy usage

    OpenAIRE

    Canbay, Çağlar Selçuk; Hepbaşlı, Arif; Gökçen Akkurt, Gülden

    2004-01-01

    Heating, ventilating and air-conditioning (HVAC) systems in buildings must be integrated with an efficient control scheme to maintain comfort under any load conditions. Efficient HVAC control is often the most cost-effective option to improve the energy efficiency of a building. However, HVAC processes are non-linear, and characteristics change on a seasonal basis so the effect of changing the control strategy is usually difficult to predict. The present study aims to reduce energy consumptio...

  1. A strategy to minimize the energy offset in carrier injection from excited dyes to inorganic semiconductors for efficient dye-sensitized solar energy conversion.

    Science.gov (United States)

    Fujisawa, Jun-Ichi; Osawa, Ayumi; Hanaya, Minoru

    2016-08-10

    Photoinduced carrier injection from dyes to inorganic semiconductors is a crucial process in various dye-sensitized solar energy conversions such as photovoltaics and photocatalysis. It has been reported that an energy offset larger than 0.2-0.3 eV (threshold value) is required for efficient electron injection from excited dyes to metal-oxide semiconductors such as titanium dioxide (TiO2). Because the energy offset directly causes loss in the potential of injected electrons, it is a crucial issue to minimize the energy offset for efficient solar energy conversions. However, a fundamental understanding of the energy offset, especially the threshold value, has not been obtained yet. In this paper, we report the origin of the threshold value of the energy offset, solving the long-standing questions of why such a large energy offset is necessary for the electron injection and which factors govern the threshold value, and suggest a strategy to minimize the threshold value. The threshold value is determined by the sum of two reorganization energies in one-electron reduction of semiconductors and typically-used donor-acceptor (D-A) dyes. In fact, the estimated values (0.21-0.31 eV) for several D-A dyes are in good agreement with the threshold value, supporting our conclusion. In addition, our results reveal that the threshold value is possible to be reduced by enlarging the π-conjugated system of the acceptor moiety in dyes and enhancing its structural rigidity. Furthermore, we extend the analysis to hole injection from excited dyes to semiconductors. In this case, the threshold value is given by the sum of two reorganization energies in one-electron oxidation of semiconductors and D-A dyes.

  2. Electrostatic contribution to DNA condensation - application of 'energy minimization' in a simple model in strong Coulomb coupling regime

    CERN Document Server

    Mukherjee, Arup K

    2011-01-01

    Bending of DNA from a straight rod to a circular form in presence of any of the mono-, di-, tri- or tetravalent counterions has been simulated in strong Coulomb coupling environment employing a previously developed energy minimization simulation technique. The inherent characteristics of the simulation technique allow monitoring the required electrostatic contribution to the bending. The curvature of the bending has been found to play crucial roles in facilitating electrostatic attractive potential energy. The total electrostatic potential energy has been found to decrease with bending which indicates that bending a straight DNA to a circular form or to a toroidal form in presence of neutralizing counterions is energetically favorable and practically is a spontaneous phenomenon.

  3. When the lowest energy does not induce native structures: parallel minimization of multi-energy values by hybridizing searching intelligences.

    Directory of Open Access Journals (Sweden)

    Qiang Lü

    Full Text Available BACKGROUND: Protein structure prediction (PSP, which is usually modeled as a computational optimization problem, remains one of the biggest challenges in computational biology. PSP encounters two difficult obstacles: the inaccurate energy function problem and the searching problem. Even if the lowest energy has been luckily found by the searching procedure, the correct protein structures are not guaranteed to obtain. RESULTS: A general parallel metaheuristic approach is presented to tackle the above two problems. Multi-energy functions are employed to simultaneously guide the parallel searching threads. Searching trajectories are in fact controlled by the parameters of heuristic algorithms. The parallel approach allows the parameters to be perturbed during the searching threads are running in parallel, while each thread is searching the lowest energy value determined by an individual energy function. By hybridizing the intelligences of parallel ant colonies and Monte Carlo Metropolis search, this paper demonstrates an implementation of our parallel approach for PSP. 16 classical instances were tested to show that the parallel approach is competitive for solving PSP problem. CONCLUSIONS: This parallel approach combines various sources of both searching intelligences and energy functions, and thus predicts protein conformations with good quality jointly determined by all the parallel searching threads and energy functions. It provides a framework to combine different searching intelligence embedded in heuristic algorithms. It also constructs a container to hybridize different not-so-accurate objective functions which are usually derived from the domain expertise.

  4. Waste minimization policies, regulations, and practices within the U.S. Department of Energy defense programs

    Energy Technology Data Exchange (ETDEWEB)

    Mathur, S.P.

    1989-11-01

    In 1984 the US Congress enacted the Hazardous and Solid Waste Amendments (HSWA) to the Resource Conservation and Recovery Act (RCRA). One of the goals of this legislation was to focus attention on the need to reduce or eliminate hazardous waste so as to minimize the threat to human health and the environment. Subsequently, in September of 1988, DOE issued a Radioactive Waste Management Policy, DOE Order 5820.2A, and in November a General Environmental Program Order, DOE Order 5400.1. These documents embrace the principles set forth in RCRA, and expand their scope to include radioactive, mixed, and pollutant waste, and all actions for reducing waste from the point of generation through waste treatment, storage, transportation and disposal. This paper will present an overview of the legislation and policies for waste reduction and, in addition, give site responsibilities for implementing waste reduction program activities.

  5. Waste minimization policies, regulations, and practices within the U.S. Department of Energy defense programs

    Energy Technology Data Exchange (ETDEWEB)

    Mathur, S.P.

    1989-11-01

    In 1984 the US Congress enacted the Hazardous and Solid Waste Amendments (HSWA) to the Resource Conservation and Recovery Act (RCRA). One of the goals of this legislation was to focus attention on the need to reduce or eliminate hazardous waste so as to minimize the threat to human health and the environment. Subsequently, in September of 1988, DOE issued a Radioactive Waste Management Policy, DOE Order 5820.2A, and in November a General Environmental Program Order, DOE Order 5400.1. These documents embrace the principles set forth in RCRA, and expand their scope to include radioactive, mixed, and pollutant waste, and all actions for reducing waste from the point of generation through waste treatment, storage, transportation and disposal. This paper will present an overview of the legislation and policies for waste reduction and, in addition, give site responsibilities for implementing waste reduction program activities.

  6. Evaluating performance indices of a shopping centre and implementing HVAC control principles to minimize energy usage

    Energy Technology Data Exchange (ETDEWEB)

    Canbay, C.S. [Energy Engineering Programme, Izmir Institute of Technology, Izmir (Turkey); Hepbasli, A. [Faculty of Engineering, Mechanical Engineering Department, Ege University, Izmir (Turkey); Gokcen, G. [Faculty of Engineering, Mechanical Engineering Department, Izmir Institute of Technology, Izmir (Turkey)

    2004-07-01

    Heating, ventilation and air-conditioning (HVAC) systems in buildings must be integrated with an efficient control scheme to maintain comfort under any load conditions. Efficient HVAC control is often the most cost-effective option to improve the energy efficiency of a building. However, HVAC processes are non-linear, and characteristics change on a seasonal basis, so the effect of changing the control strategy is usually difficult to predict. The present study aims to reduce energy consumption by defining new HVAC control strategies and tuning control loops in a shopping centre. First, an energy audit was performed to investigate the potential for energy savings and to redefine the control scenarios, while a methodology for the shopping centre was developed. Performance indices were then calculated and compared with the yardsticks. Next, normalised performance indices were computed to reach out a better understanding of the building's efficiency. Finally, new strategies were implemented with the help of the existing building management system (BMS) and about 22% of energy saving was achieved. (author)

  7. Biomechanical energy harvesting: generating electricity during walking with minimal user effort.

    Science.gov (United States)

    Donelan, J M; Li, Q; Naing, V; Hoffer, J A; Weber, D J; Kuo, A D

    2008-02-08

    We have developed a biomechanical energy harvester that generates electricity during human walking with little extra effort. Unlike conventional human-powered generators that use positive muscle work, our technology assists muscles in performing negative work, analogous to regenerative braking in hybrid cars, where energy normally dissipated during braking drives a generator instead. The energy harvester mounts at the knee and selectively engages power generation at the end of the swing phase, thus assisting deceleration of the joint. Test subjects walking with one device on each leg produced an average of 5 watts of electricity, which is about 10 times that of shoe-mounted devices. The cost of harvesting-the additional metabolic power required to produce 1 watt of electricity-is less than one-eighth of that for conventional human power generation. Producing substantial electricity with little extra effort makes this method well-suited for charging powered prosthetic limbs and other portable medical devices.

  8. Energy and environment in the 21st century : minimizing climate change.

    CERN Document Server

    CERN. Geneva

    2003-01-01

    Energy demand and economic output are coupled. Both are expected to vastly increase in this century, driven primarily by the economic and population growth of the developing world. If the present reliance on carbon-based fuels as primary energy sources continues, average global temperatures are projected to rise between 3° C and 6° C. Limiting climate change will require reduction in greenhouse gas emissions far beyond the Kyoto commitments. Time scales and options, including nuclear, will be reviewed.

  9. Guide to Setting Thermal Comfort Criteria and Minimizing Energy Use in Delivering Thermal Comfort

    Energy Technology Data Exchange (ETDEWEB)

    Regnier, Cindy

    2012-08-31

    Historically thermal comfort in buildings has been controlled by simple dry bulb temperature settings. As we move into more sophisticated low energy building systems that make use of alternate systems such as natural ventilation, mixed mode system and radiant thermal conditioning strategies, a more complete understanding of human comfort is needed for both design and control. This guide will support building designers, owners, operators and other stakeholders in defining quantifiable thermal comfort parameters?these can be used to support design, energy analysis and the evaluation of the thermal comfort benefits of design strategies. This guide also contains information that building owners and operators will find helpful for understanding the core concepts of thermal comfort. Whether for one building, or for a portfolio of buildings, this guide will also assist owners and designers in how to identify the mechanisms of thermal comfort and space conditioning strategies most important for their building and climate, and provide guidance towards low energy design options and operations that can successfully address thermal comfort. An example of low energy design options for thermal comfort is presented in some detail for cooling, while the fundamentals to follow a similar approach for heating are presented.

  10. Guide to Setting Thermal Comfort Criteria and Minimizing Energy Use in Delivering Thermal Comfort

    Energy Technology Data Exchange (ETDEWEB)

    Regnier, Cindy [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2012-08-01

    Historically thermal comfort in buildings has been controlled by simple dry bulb temperature settings. As we move into more sophisticated low energy building systems that make use of alternate systems such as natural ventilation, mixed mode system and radiant thermal conditioning strategies, a more complete understanding of human comfort is needed for both design and control. This guide will support building designers, owners, operators and other stakeholders in defining quantifiable thermal comfort parameters?these can be used to support design, energy analysis and the evaluation of the thermal comfort benefits of design strategies. This guide also contains information that building owners and operators will find helpful for understanding the core concepts of thermal comfort. Whether for one building, or for a portfolio of buildings, this guide will also assist owners and designers in how to identify the mechanisms of thermal comfort and space conditioning strategies most important for their building and climate, and provide guidance towards low energy design options and operations that can successfully address thermal comfort. An example of low energy design options for thermal comfort is presented in some detail for cooling, while the fundamentals to follow a similar approach for heating are presented.

  11. A note on the energy-efficiency investments of an expected cost minimizer

    NARCIS (Netherlands)

    Kooreman, P.; Steerneman, A.G.M.

    1998-01-01

    This paper analyzes a consumer's choice between a high-efficiency and a low-efficiency version of an energy-using durable when the expected lifetimes of the two versions differ. A (small) difference in expected lifetimes may induce entirely different implications for the behavior of st cost minimizi

  12. Energy minimization using Sobolev gradients application to phase separation and ordering

    CERN Document Server

    Sial, S; Lookman, T; Saxena, A

    2003-01-01

    A common problem in physics and engineering is the calculation of the minima of energy functionals. The theory of Sobolev gradients provides an efficient method for seeking the critical points of such a functional. We apply the method to functionals describing coarse-grained Ginzburg-Landau models commonly used in pattern formation and ordering processes.

  13. Electromechanical Battery EMB Mass Minimization taking into Account its Electrical Machines Rotor Energy

    Directory of Open Access Journals (Sweden)

    Podgornovs Andrejs

    2014-12-01

    Full Text Available In this paper the electromechanical battery (EMB with synchronous machine is described. Theoretically, if electrical machines rotor stored energy is known, it is possible to reduce the flywheel mass of electromechanical battery. For example, the efficiency of energy recovery (kilowatt-hours out versus kilowatthours in in nowadays appliances exceeds 95 % which is considerably better than of any electrochemical battery, such as lead-acid battery. For the rotor stored energy amount calculation, it is necessary to find all geometrical dimensions of the electrical machine. To achieve this goal the iterative calculation method was used. Electromechanical battery mass was analyzed as a discharge process rotation speed function. Taking into account the rotor stored energy, we can increase the minimum rotation speed thus reducing the electrical machine mass and increasing the flywheel mass, which provides EMB cost reduction. Additionally, the possibilities of using numerical approximation calculations of magnetization curves are discussed. Each iteration of numerical application necessary for the method for rapid calculation is essential when calculating the field problems. Nowadays there are a lot of computer added design programs for electromagnetic field calculation in different types of applications, electrical machines and apparatus. For the electromagnetic field calculation process some more commonly used magnetization curve approximation methods are described, and the machine calculation time is tested for different numbers of calculations.

  14. Energy Minimization of Discrete Protein Titration State Models Using Graph Theory

    Energy Technology Data Exchange (ETDEWEB)

    Purvine, Emilie AH; Monson, Kyle E.; Jurrus, Elizabeth R.; Star, Keith T.; Baker, Nathan A.

    2016-09-01

    There are several applications in computational biophysics which require the optimization of discrete interacting states; e.g., amino acid titration states, ligand oxidation states, or discrete rotamer angles. Such optimization can be very time-consuming as it scales exponentially in the number of sites to be optimized. In this paper, we describe a new polynomial-time algorithm for optimization of discrete states in macromolecular systems. This algorithm was adapted from image processing and uses techniques from discrete mathematics and graph theory to restate the optimization problem in terms of maximum flow-minimum cut graph analysis. The interaction energy graph, a graph in which vertices (amino acids) and edges (interactions) are weighted with their respective energies, is transformed into a flow network in which the value of the minimum cut in the network equals the minimum free energy of the protein, and the cut itself encodes the state that achieves the minimum free energy. Because of its deterministic nature and polynomial-time performance, this algorithm has the potential to allow for the ionization state of larger proteins to be discovered.

  15. Minimal quartet-metric gravity: beyond LCDM per scalar graviton as the unified dark matter and dark energy

    CERN Document Server

    Pirogov, Yury F

    2016-01-01

    In the framework of the minimal quartet-metric gravity/systogravity, a scalar graviton/systolon is stated as a universal dark component, with supplementary manifestations in the different contexts either as dark matter or dark energy. An ensuing extension to the standard {\\Lambda}CDM model is developed. A modification of the late expansion of the Universe, with an attractor of a scalar master equation defining an effective cosmological constant, which supersedes the true one, is proposed. A new partial solution to the cosmological constant problem is discussed.

  16. A Method for Online Steady State Energy Minimization with Application to Refrigeration Systems

    DEFF Research Database (Denmark)

    Larsen, Lars Finn Slot; Thybo, Claus; Stoustrup, Jakob;

    2004-01-01

    Energy efficiency of refrigeration systems has gradually been improved with the help of control schemes utilizing the more flexible components; the efficiency is though yet far from optimal. The flexibility initiates a higher degree of freedom in choosing the operating set points while obtaining...... the required cooling capacity. This paper proposes an approach which utilizes this newly gained degree of freedom to drive the system towards the energy optimal set-point while keeping up the cooling capacity. The focus of this paper is on refrigeration system however the generality of the proposed method thus...... applies to a broader range of process systems where the lower level set-points (in the control hierarchy) can be chosen within a degree of freedom allowing an optimization of a steady state performance index....

  17. Minimizing Wind Power Producer's Balancing Costs Using Electrochemical Energy Storage: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Miettinen, J.; Tikka, V.; Lassila, J.; Partanen, J.; Hodge, B. M.

    2014-08-01

    This paper examines how electrochemical energy storage can be used to decrease the balancing costs of a wind power producer in the Nordic market. Because electrochemical energy storage is developing in both technological and financial terms, a sensitivity analysis was carried out for the most important variables in the wind-storage hybrid system. The system was studied from a wind power producer's point of view. The main result is that there are no technical limitations to using storage for reducing the balancing costs. However, in terms of economic feasibility, installing hybrid wind-storage systems such as the one studied in this paper faces challenges in both the short and long terms.

  18. Minimizing Wind Power Producer's Balancing Costs Using Electrochemical Energy Storage: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Miettinen, J.; Tikka, V.; Lassila, J.; Partanen, J.; Hodge, B. M.

    2014-08-01

    This paper examines how electrochemical energy storage can be used to decrease the balancing costs of a wind power producer in the Nordic market. Because electrochemical energy storage is developing in both technological and financial terms, a sensitivity analysis was carried out for the most important variables in the wind-storage hybrid system. The system was studied from a wind power producer's point of view. The main result is that there are no technical limitations to using storage for reducing the balancing costs. However, in terms of economic feasibility, installing hybrid wind-storage systems such as the one studied in this paper faces challenges in both the short and long terms.

  19. Optimal Intra-Urban Hierarchy of Activity Centers—A Minimized Household Travel Energy Consumption Approach

    Directory of Open Access Journals (Sweden)

    Jie Zhang

    2015-08-01

    Full Text Available An intra-urban hierarchy of activity centers interconnected by non-motorized and public transportation is broadly believed to be the ideal urban spatial structure for sustainable cities. However, the proper hinterland area for centers at each level lacks empirical study. Based on the concentric structure of everyday travel distances, working centers, shopping centers, and neighborhood centers are extracted from corresponding types of POIs in 286 Chinese cities at the prefectural level and above. A U-shaped curve between Household Transportation Energy Consumption (HTEC per capita and center density at each of the three levels has been found through regression analysis. An optimal intra-urban hierarchy of activity centers is suggested to construct energy-efficient cities.

  20. Green Computing – An Eco friendly Approach for Energy Efficiency and Minimizing E-Waste

    Directory of Open Access Journals (Sweden)

    Vinoth Kumar T., Kiruthiga P.

    2014-05-01

    Full Text Available The need for environmentally friendly computing gadgets and energy saving devices, under the auspices of „Green Computing‟ has become a global phenomenon with the aim to reduce environmental decadence that emanates from abuse and the rising threat of global warming. . “Green computing” represents environmentally responsible way to reduce power and environmental e-waste. Green computing is the practice of using computing resources efficiently. The goals are to reduce the use of hazardous materials, maximize energy efficiency during the product's lifetime, and promote recyclability or biodegradability of defunct products and factory waste. It‟s known that as the economy expands, the demand for computing devices rises as business and individuals seek faster way of doing things –„‟The Computing way‟‟. Information technological devices are upgraded rapidly due to the need for speed, flexibility, simplicity and cost effectiveness; thus outdating the previous technology. Hence we need to implement energy-efficient central processing units (CPUs, servers and peripherals with reduced resource consumption and proper disposal of electronic waste (e-waste.

  1. Minimizing the expenditure of energy when scheduling the sequence of observations of astronomical objects from spacecraft

    Science.gov (United States)

    Belyaev, M. Yu.; Legostaev, V. P.; Rulev, D. N.

    2013-12-01

    An approach to solving the problem of optimal scheduling of the sequence of spacecraft reorientations during observations of astronomical objects is discussed. The approach is based on problem formalization within the framework of graph theory and reduction of the problem to routing. Examples of constructing optimal observational programs for chosen stars are given. These examples show that the proposed approach offers the possibility of a significant reduction in energy expenditures for spacecraft reorientation. The applicability of the mentioned approach to optimizing traffic routes in various subnational entities is noted.

  2. A biomolecular implementation of logically reversible computation with minimal energy dissipation.

    Science.gov (United States)

    Klein, J P; Leete, T H; Rubin, H

    1999-10-01

    Energy dissipation associated with logic operations imposes a fundamental physical limit on computation and is generated by the entropic cost of information erasure, which is a consequence of irreversible logic elements. We show how to encode information in DNA and use DNA amplification to implement a logically reversible gate that comprises a complete set of operators capable of universal computation. We also propose a method using this design to connect, or 'wire', these gates together in a biochemical fashion to create a logic network, allowing complex parallel computations to be executed. The architecture of the system permits highly parallel operations and has properties that resemble well known genetic regulatory systems.

  3. Nuclear Effects in Neutrino Interactions with Minimal Neutrino Energy Dependence -- A NuWro Truth Study

    CERN Document Server

    Pickering, Luke

    2016-01-01

    We present a Monte Carlo truth study examining nuclear effects in charged-current neutrino interactions using observables constructed in the transverse plane. Three distributions are introduced that show very weak dependence on neutrino flux and its associated uncertainty. Measurements comparing these distributions between quasi-elastic-like and single charged pion final states will provide new constraints of nuclear effects. It is suggested that the on-axis position in the NuMI beam provides the correct flux to take advantage of this reduced energy dependence in measuring nuclear effect-generated transverse imbalances.

  4. Design and Validation of Real-Time Optimal Control with ECMS to Minimize Energy Consumption for Parallel Hybrid Electric Vehicles

    Directory of Open Access Journals (Sweden)

    Aiyun Gao

    2017-01-01

    Full Text Available A real-time optimal control of parallel hybrid electric vehicles (PHEVs with the equivalent consumption minimization strategy (ECMS is presented in this paper, whose purpose is to achieve the total equivalent fuel consumption minimization and to maintain the battery state of charge (SOC within its operation range at all times simultaneously. Vehicle and assembly models of PHEVs are established, which provide the foundation for the following calculations. The ECMS is described in detail, in which an instantaneous cost function including the fuel energy and the electrical energy is proposed, whose emphasis is the computation of the equivalent factor. The real-time optimal control strategy is designed through regarding the minimum of the total equivalent fuel consumption as the control objective and the torque split factor as the control variable. The validation of the control strategy proposed is demonstrated both in the MATLAB/Simulink/Advisor environment and under actual transportation conditions by comparing the fuel economy, the charge sustainability, and parts performance with other three control strategies under different driving cycles including standard, actual, and real-time road conditions. Through numerical simulations and real vehicle tests, the accuracy of the approach used for the evaluation of the equivalent factor is confirmed, and the potential of the proposed control strategy in terms of fuel economy and keeping the deviations of SOC at a low level is illustrated.

  5. Minimization of the energy loss of nuclear power plants in case of partial in-core monitoring system failure

    Science.gov (United States)

    Zagrebaev, A. M.; Ramazanov, R. N.; Lunegova, E. A.

    2017-01-01

    In this paper we consider the optimization problem minimize of the energy loss of nuclear power plants in case of partial in-core monitoring system failure. It is possible to continuation of reactor operation at reduced power or total replacement of the channel neutron measurements, requiring shutdown of the reactor and the stock of detectors. This article examines the reconstruction of the energy release in the core of a nuclear reactor on the basis of the indications of height sensors. The missing measurement information can be reconstructed by mathematical methods, and replacement of the failed sensors can be avoided. It is suggested that a set of ‘natural’ functions determined by means of statistical estimates obtained from archival data be constructed. The procedure proposed makes it possible to reconstruct the field even with a significant loss of measurement information. Improving the accuracy of the restoration of the neutron flux density in partial loss of measurement information to minimize the stock of necessary components and the associated losses.

  6. Use of Binary Partition Tree and energy minimization for object-based classification of urban land cover

    Science.gov (United States)

    Li, Mengmeng; Bijker, Wietske; Stein, Alfred

    2015-04-01

    Two main challenges are faced when classifying urban land cover from very high resolution satellite images: obtaining an optimal image segmentation and distinguishing buildings from other man-made objects. For optimal segmentation, this work proposes a hierarchical representation of an image by means of a Binary Partition Tree (BPT) and an unsupervised evaluation of image segmentations by energy minimization. For building extraction, we apply fuzzy sets to create a fuzzy landscape of shadows which in turn involves a two-step procedure. The first step is a preliminarily image classification at a fine segmentation level to generate vegetation and shadow information. The second step models the directional relationship between building and shadow objects to extract building information at the optimal segmentation level. We conducted the experiments on two datasets of Pléiades images from Wuhan City, China. To demonstrate its performance, the proposed classification is compared at the optimal segmentation level with Maximum Likelihood Classification and Support Vector Machine classification. The results show that the proposed classification produced the highest overall accuracies and kappa coefficients, and the smallest over-classification and under-classification geometric errors. We conclude first that integrating BPT with energy minimization offers an effective means for image segmentation. Second, we conclude that the directional relationship between building and shadow objects represented by a fuzzy landscape is important for building extraction.

  7. Energy minimization of separation processes using conventional/membrane hybrid systems

    Energy Technology Data Exchange (ETDEWEB)

    Gottschlich, D.E.; Roberts, D.L. (SRI International, Menlo Park, CA (USA))

    1990-09-28

    The purpose of this study was to identify the general principles governing the choice of hybrid separation systems over straight membrane or straight nonmembrane systems and to do so by examining practical applications (process design and economics). Our focus was to examine the energy consumption characteristics and overall cost factors of the membrane and nonmembrane technologies that cause hybrid systems to be preferred over nonhybrid systems. We evaluated four cases studies, chosen on the basis of likelihood of commercial viability of a hybrid system and magnitude of energy savings: (1) propane/propylene separation; (2) removal of nitrogen from natural gas; (3) concentration of Kraft black liquor; and (4)solvent deasphalting. For propane/propylene splitting, the membrane proved to be superior to distillation in both thermodynamic efficiency and processing cost (PC) when the product was 95% pure propylene. However, to produce higher purity products, the membrane alone could not perform the separation, and a membrane/distillation hybrid was required. In these cases, there is an optimum amount of separation to be accomplished by the membrane (expressed as the fraction of the total availability change of the membrane/distillation hybrid that takes place in the membrane and defined as {phi}{sub m}, the thermodynamic extent of separation). Qualitative and quantitative guidelines are discussed with regard to choosing a hybrid system. 54 refs., 66 figs., 36 tabs.

  8. Final Technical Report - Advanced Optical Sensors to Minimize Energy Consumption in Polymer Extrusion Processes

    Energy Technology Data Exchange (ETDEWEB)

    Susan J. Foulk

    2012-07-24

    Project Objective: The objectives of this study are to develop an accurate and stable on-line sensor system to monitor color and composition on-line in polymer melts, to develop a scheme for using the output to control extruders to eliminate the energy, material and operational costs of off-specification product, and to combine or eliminate some extrusion processes. Background: Polymer extrusion processes are difficult to control because the quality achieved in the final product is complexly affected by the properties of the extruder screw, speed of extrusion, temperature, polymer composition, strength and dispersion properties of additives, and feeder system properties. Extruder systems are engineered to be highly reproducible so that when the correct settings to produce a particular product are found, that product can be reliably produced time after time. However market conditions often require changes in the final product, different products or grades may be processed in the same equipment, and feed materials vary from lot to lot. All of these changes require empirical adjustment of extruder settings to produce a product meeting specifications. Optical sensor systems that can continuously monitor the composition and color of the extruded polymer could detect process upsets, drift, blending oscillations, and changes in dispersion of additives. Development of an effective control algorithm using the output of the monitor would enable rapid corrections for changes in materials and operating conditions, thereby eliminating most of the scrap and recycle of current processing. This information could be used to identify extruder systems issues, diagnose problem sources, and suggest corrective actions in real-time to help keep extruder system settings within the optimum control region. Using these advanced optical sensor systems would give extruder operators real-time feedback from their process. They could reduce the amount of off-spec product produced and

  9. Detuning Minimization of Induction Motor Drive System for Alternative Energy Vehicles

    Directory of Open Access Journals (Sweden)

    Habibur Rehman

    2015-08-01

    Full Text Available This paper evaluates different types of AC machines and various control techniques for their suitability for the drive system of Alternative Energy Vehicles (AEV. An Indirect Field Oriented (IFO drive system for the AEV application is chosen and its major problem of detuning is addressed by designing an offline and an online rotor resistance adaptation technique. The offline scheme sets the slip gain at various operating conditions based on the fact that if the rotor resistance is set correctly and field orientation is achieved, then there should be a linear relationship between the torque current and the output torque. The online technique is designed using Model Reference Adaptive System (MRAS for the rotor resistance adaptation. For an ideal field oriented machine, the rotor flux along the q-axis should be zero. This condition acts as a reference model for the proposed MRAS scheme. The current model flux observer in the synchronous frame of reference is selected as an adjustable model and its rotor resistance is tuned so that the flux along the q-axis becomes zero. The effectiveness of the offline tuning scheme is evident through performance validation of the drive system, which is implemented in a real Ford vehicle. The experimental results obtained while driving the test vehicle are included in the paper while the proposed online scheme is validated on a 3.75 kW prototype induction motor.

  10. Expanding gas clouds of ellipsoidal shape - the solutions of minimal energy

    Science.gov (United States)

    Gaffet, B.

    1999-07-01

    Ovsiannikov [Dokl. Akad. Nauk SSSR 111 (1965)] and Dyson [J. Math. Mech. 18 (1968) 91] have proposed a model of an ellipsoidal gas cloud adiabatically expanding into a vacuum, and have shown that the equations of fluid motion are thereby reduced to a set of ordinary differential equations, of order 18 in the most general case. Gaffet [J. Fluid Mech. 325 (1996) 113] has shown that their integration reduces to quadratures (if the gas is monatomic and there is no rotating motion of the ellipsoid’s principal axes), as a result of the existence of two integrals of the motion, m and I2. In the present work we establish the minimum value m0( I2) of m, compatible with the existence of physically meaningful solutions. We succeed in performing the separation of variables, and obtain the unexpected result that, when the energy integral m takes its minimum value m0( I2), the general solution of the equations of motion is described by elliptic functions.

  11. A Gibbs Energy Minimization Approach for Modeling of Chemical Reactions in a Basic Oxygen Furnace

    Science.gov (United States)

    Kruskopf, Ari; Visuri, Ville-Valtteri

    2017-08-01

    In modern steelmaking, the decarburization of hot metal is converted into steel primarily in converter processes, such as the basic oxygen furnace. The objective of this work was to develop a new mathematical model for top blown steel converter, which accounts for the complex reaction equilibria in the impact zone, also known as the hot spot, as well as the associated mass and heat transport. An in-house computer code of the model has been developed in Matlab. The main assumption of the model is that all reactions take place in a specified reaction zone. The mass transfer between the reaction volume, bulk slag, and metal determine the reaction rates for the species. The thermodynamic equilibrium is calculated using the partitioning of Gibbs energy (PGE) method. The activity model for the liquid metal is the unified interaction parameter model and for the liquid slag the modified quasichemical model (MQM). The MQM was validated by calculating iso-activity lines for the liquid slag components. The PGE method together with the MQM was validated by calculating liquidus lines for solid components. The results were compared with measurements from literature. The full chemical reaction model was validated by comparing the metal and slag compositions to measurements from industrial scale converter. The predictions were found to be in good agreement with the measured values. Furthermore, the accuracy of the model was found to compare favorably with the models proposed in the literature. The real-time capability of the proposed model was confirmed in test calculations.

  12. Thermodynamic free-energy minimization for unsupervised fusion of dual-color infrared breast images

    Science.gov (United States)

    Szu, Harold; Miao, Lidan; Qi, Hairong

    2006-04-01

    function [A] may vary from the point tumor to its neighborhood, we could not rely on neighborhood statistics as did in a popular unsupervised independent component analysis (ICA) mathematical statistical method, we instead impose the physics equilibrium condition of the minimum of Helmholtz free-energy, H = E - T °S. In case of the point breast cancer, we can assume the constant ground state energy E ° to be normalized by those benign neighborhood tissue, and then the excited state can be computed by means of Taylor series expansion in terms of the pixel I/O data. We can augment the X-ray mammogram technique with passive IR imaging to reduce the unwanted X-rays during the chemotherapy recovery. When the sequence is animated into a movie, and the recovery dynamics is played backward in time, the movie simulates the cameras' potential for early detection without suffering the PD=0.1 search uncertainty. In summary, we applied two satellite-grade dual-color IR imaging cameras and advanced military (automatic target recognition) ATR spectrum fusion algorithm at the middle wavelength IR (3 - 5μm) and long wavelength IR (8 - 12μm), which are capable to screen malignant tumors proved by the time-reverse fashion of the animated movie experiments. On the contrary, the traditional thermal breast scanning/imaging, known as thermograms over decades, was IR spectrum-blind, and limited to a single night-vision camera and the necessary waiting for the cool down period for taking a second look for change detection suffers too many environmental and personnel variabilities.

  13. Minimal Pairs: Minimal Importance?

    Science.gov (United States)

    Brown, Adam

    1995-01-01

    This article argues that minimal pairs do not merit as much attention as they receive in pronunciation instruction. There are other aspects of pronunciation that are of greater importance, and there are other ways of teaching vowel and consonant pronunciation. (13 references) (VWL)

  14. Optimizing cost and minimizing energy loss in the recirculating race-track design of the LHeC electron linac

    CERN Document Server

    Skrabacz, J

    2008-01-01

    The objective of this project is to propose an optimal design of a recirculating electron linac for a future LHC-based e-p collider_the LHeC [1, 2]. Primary considerations are the cost, structure, shape, and size of the recirculating track, the optimal number of revolutions through which the e-beam should be accelerated, and radiative energy loss in the bends. Secondary considerations are transverse emittance growth due to radiation, the number of dipoles needed in order to maintain an upper bound on the emittance growth, the average length of such dipoles, and the maximum bending dipole field needed to recirculate the beam. These effects will be studied macroscopically with respect to the overall structure, in that smaller effects related to machine optics of the lattice structure will be neglected. The scope of the optimization problem is, in essence, a "first order" insight into optimal dimensions, centered on minimizing the most important parameter_cost.

  15. Thermodynamic analysis of combined reforming process using Gibbs energy minimization method: In view of solid carbon formation

    Institute of Scientific and Technical Information of China (English)

    Behzad Nematollahi; Mehran Rezaei; Ebrahim Nemati Lay; Majid Khajenoori

    2012-01-01

    Thermodynamic analysis was applied to study combined partial oxidation and carbon dioxide reforming of methane in view of carbon for-mation.The equilibrium calculations employing the Gibbs energy minimization were performed upon wide ranges of pressure (1-25 atm),temperature (600-1300 K),carbon dioxide to methane ratio (0-2) and oxygen to methane ratio (0-1).The thermodynamic results were compared with the results obtained over a Ru supported catalyst.The results revealed that by increasing the reaction pressure methane conversion decreased.Also it was found that the atmospheric pressure is the preferable pressure for both dry reforming and partial oxidation of methane and increasing the temperature caused increases in both activity of carbon and conversion of methane.The results clearly showed that the addition of O2 to the feed mixture could lead to a reduction of carbon deposition.

  16. Numerical simulation of dense particle-gas two-phase flow using the minimal potential energy principle

    Institute of Scientific and Technical Information of China (English)

    Xiangjun Liu; Xuchang Xu; Wurong Zhang

    2006-01-01

    A simulation method of dense particle-gas two-phase flow has been developed. The binding force is introduced to present the impact of particle clustering and its expression is deduced according to the principle of minimal potential energy. The cluster collision,break-up and coalescence models are proposed based on the assumption that the particle cluster are treated as one discrete phase. These models are used to numerically study the two-phase flow field in a circulating fluidized bed (CFB). Detailed results of the cluster structure, cluster size, particle volume fraction, gas velocity, and particle velocity are obtained. The correlation between the simulation results and experimental data justifies that these models and algorithm are reasonable, and can be used to efficiently study the dense particle-gas two-phase flow.

  17. Increasing the percentage of energy from dietary sugar, fats, and alcohol in adults is associated with increased energy intake but has minimal association with biomarkers of cardiovascular risk.

    Science.gov (United States)

    Austin, Gregory L; Krueger, Patrick M

    2013-10-01

    The optimal diet composition to prevent obesity and its complications is unknown. Study aims were to determine the association of diet composition with energy intake, homeostatic model assessment-insulin resistance (HOMA-IR), and C-reactive protein (CRP). Data were from the NHANES for eligible adults aged 20-74 y from 2005 to 2006 (n = 3073). Energy intake and diet composition were obtained by dietary recall. HOMA-IR was calculated from fasting insulin and glucose concentrations, and CRP was measured directly. Changes for a 1-point increase in percentage of sugar, saturated fatty acids (SFAs), monounsaturated fatty acids (MUFAs), polyunsaturated fatty acids (PUFAs), and alcohol were determined across their means in exchange for a 1-point decrease in percentage of nonsugar carbohydrates. Regression analyses were performed, and means ± SEs were estimated. Increasing the percentage of sugar was associated with increased energy intake in men (23 ± 5 kcal; P intake. In women, increasing percentages of SFAs (27 ± 10 kcal; P = 0.02), PUFAs (43 ± 6 kcal; P intake. Increasing the percentage of alcohol was associated with increased energy intake in men (38 ± 7 kcal; P sugar, fats, and alcohol was associated with substantially increased energy intake but had minimal association with HOMA-IR and CRP.

  18. Vibration attenuation of rotating machines by application of magnetorheological dampers to minimize energy losses in the rotor support

    Science.gov (United States)

    Zapoměl, J.; Ferfecki, P.

    2016-09-01

    A frequently used technological solution for minimization of undesirable effects caused by vibration of rotating machines consists in placing damping devices in the rotor supports. The application of magnetorheological squeeze film dampers enables their optimum performance to be achieved in a wide range of rotating speeds by adapting their damping effect to the current operating conditions. The damping force, which is produced by squeezing the layer of magnetorheological oil, can be controlled by changing magnetic flux passing through the lubricant. The force acting between the rotor and its frame is transmitted through the rolling element bearing, the lubricating layer and the squirrel spring. The loading of the bearing produces a time variable friction moment, energy losses, uneven rotor running, and has an influence on the rotor service life and the current fluctuation in electric circuits. The carried out research consisted in the development of a mathematical model of a magnetorheological squeeze film damper, its implementation into the computational models of rotor systems, and in performing the study on the dependence of the energy losses and variation of the friction moment on the damping force and its control. The new and computationally stable mathematical model of a magnetorheological squeeze film damper, its implementation in the computational models of rigid rotors and learning more on the energy losses generated in the rotor supports in dependence on the damping effect are the principal contributions of this paper. The results of the computational simulations prove that a suitable control of the damping force enables the energy losses to be reduced in a wide velocity range.

  19. Constraints on secondary 10-100 EeV gamma ray flux in the minimal bottom-up model of Ultra High Energy Cosmic Rays

    CERN Document Server

    Kalashev, O; Semikoz, Dmitry V

    2007-01-01

    In a recently proposed model the cosmic rays spectrum at energies above EeV can be fitted with a minimal number of unknown parameters assuming that the extragalactic cosmic rays are only protons with a power law source spectrum. Within this minimal model, after fitting the observed HiRes spectrum with four parameters (proton injection spectrum power law index, maximum energy, minimum distance to sources and evolution parameter) we compute the flux of ultra-high energy photons due to photon-pion production and e+e- pair production by protons for several radio background models and a range of average extragalactic magnetic fields.

  20. THE PREDICTION OF pH BY GIBBS FREE ENERGY MINIMIZATION IN THE SUMP SOLUTION UNDER LOCA CONDITION OF PWR

    Directory of Open Access Journals (Sweden)

    HYOUNGJU YOON

    2013-02-01

    Full Text Available It is required that the pH of the sump solution should be above 7.0 to retain iodine in a liquid phase and be within the material compatibility constraints under LOCA condition of PWR. The pH of the sump solution can be determined by conventional chemical equilibrium constants or by the minimization of Gibbs free energy. The latter method developed as a computer code called SOLGASMIX-PV is more convenient than the former since various chemical components can be easily treated under LOCA conditions. In this study, SOLGASMIX-PV code was modified to accommodate the acidic and basic materials produced by radiolysis reactions and to calculate the pH of the sump solution. When the computed pH was compared with measured by the ORNL experiment to verify the reliability of the modified code, the error between two values was within 0.3 pH. Finally, two cases of calculation were performed for the SKN 3&4 and UCN 1&2. As results, pH of the sump solution for the SKN 3&4 was between 7.02 and 7.45, and for the UCN 1&2 plant between 8.07 and 9.41. Furthermore, it was found that the radiolysis reactions have insignificant effects on pH because the relative concentrations of HCl, HNO3, and Cs are very low.

  1. The prediction of pH by Gibbs free energy minimization in the sump solution under LOCA condition of PWR

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Hyoung Ju [Dept. of Nuclear Engineering, University of Kyunghee, Seoul (Korea, Republic of)

    2013-02-15

    It is required that the pH of the sump solution should be above 7.0 to retain iodine in a liquid phase and be within the material compatibility constraints under LOCA condition of PWR. The pH of the sump solution can be determined by conventional chemical equilibrium constants or by the minimization of Gibbs free energy. The latter method developed as a computer code called SOLGASMIX-PV is more convenient than the former since various chemical components can be easily treated under LOCA conditions. In this study, SOLGASMIX-PV code was modified to accommodate the acidic and basic materials produced by radiolysis reactions and to calculate the pH of the sump solution. When the computed pH was compared with measured by the ORNL experiment to verify the reliability of the modified code, the error between two values was within 0.3 pH. Finally, two cases of calculation were performed for the SKN 3 and 4 and UCN 1 and 2. As results, pH of the sump solution for the SKN 3 and 4 was between 7.02 and 7.45, and for the UCN 1 and 2 plant between 8.07 and 9.41. Furthermore, it was found that the radiolysis reactions have insignificant effects on pH because the relative concentrations of HCl, HNO3, and Cs are very low.

  2. Fill-level symmetry and minimization of energy states in rotating tumblers with polygonal cross-sections

    Science.gov (United States)

    Pohlman, Nicholas A.; Paprocki, Daniel F., Jr.; Si, Yun

    2012-11-01

    Typically in rotating tumblers, constant rotation rates and circular cross-sections are used as they jointly produce a steady, uniform flowing layer at the free surface. On the other hand, experiments conducted in polygon-shaped tumblers produce unsteady conditions due to the rapidly changing flowing layer length. Results analyzing free surface properties indicate that the particle dynamics within the flowing layer attempt to minimize energy of the flowing system: The arithmetic difference between the angle of repose and the tumbler orientation has a functional relationship with the instantaneous flowing layer length in the form of a catenary. The peaks of the catenary are affected by the number of sides on the polygon cross-section as well as the symmetry around the critical 50% fill fraction. Furthermore, oscillation of the flowing layer position appears to affect the free surface curvature. This result is likely due to the rapidly increasing and decreasing length of the free surface and the rotational inertia of particles entering the flowing layer. Funding provided by NIU's Office of Student Engagement and Experiential Learning.

  3. Three-dimensional elastic image registration based on strain energy minimization: application to prostate magnetic resonance imaging.

    Science.gov (United States)

    Zhang, Bao; Arola, Dwayne D; Roys, Steve; Gullapalli, Rao P

    2011-08-01

    The use of magnetic resonance (MR) imaging in conjunction with an endorectal coil is currently the clinical standard for the diagnosis of prostate cancer because of the increased sensitivity and specificity of this approach. However, imaging in this manner provides images and spectra of the prostate in the deformed state because of the insertion of the endorectal coil. Such deformation may lead to uncertainties in the localization of prostate cancer during therapy. We propose a novel 3-D elastic registration procedure that is based on the minimization of a physically motivated strain energy function that requires the identification of similar features (points, curves, or surfaces) in the source and target images. The Gauss-Seidel method was used in the numerical implementation of the registration algorithm. The registration procedure was validated on synthetic digital images, MR images from prostate phantom, and MR images obtained on patients. The registration error, assessed by averaging the displacement of a fiducial landmark in the target to its corresponding point in the registered image, was 0.2 ± 0.1 pixels on synthetic images. On the prostate phantom and patient data, the registration errors were 1.0 ± 0.6 pixels (0.6 ± 0.4 mm) and 1.8 ± 0.7 pixels (1.1 ± 0.4 mm), respectively. Registration also improved image similarity (normalized cross-correlation) from 0.72 ± 0.10 to 0.96 ± 0.03 on patient data. Registration results on digital images, phantom, and prostate data in vivo demonstrate that the registration procedure can be used to significantly improve both the accuracy of localized therapies such as brachytherapy or external beam therapy and can be valuable in the longitudinal follow-up of patients after therapy.

  4. Operation of solid oxide fuel cells on glycerol fuel: A thermodynamic analysis using the Gibbs free energy minimization approach

    Science.gov (United States)

    Lima da Silva, Aline; Müller, Iduvirges Lourdes

    Solid oxide fuel cells (SOFCs) are very flexible, unlike other fuel cells. In principle, SOFCs can operate on almost any fuel. Currently much effort is invested in the development of SOFCs for portable applications operating directly on liquid fuels such as methanol and ethanol rather than hydrogen. However, there are very few publications dealing with the direct use of glycerol in SOFCs for portable systems. A recently published study shows that the performance achieved for an SOFC fueled by pure glycerol is quite interesting even when there is a thick electrolyte membrane, indicating that glycerol is a promising fuel for portable applications. For this reason a thermodynamic analysis for SOFCs operating directly on glycerol fuel is performed in the present study. The Gibbs energy minimization method computes the equilibrium compositions of the anode gas mixture, carbon deposition boundaries and electromotive forces (EMFs) as a function of fuel utilization and temperature. Moreover, the minimum amounts of H 2O, CO 2 (direct internal reforming case) and air (partial oxidation case) to be added to glycerol in the feedstock to avoid carbon deposition at the open circuit voltage (OCV) are calculated. Finally, a thermodynamic analysis is performed, taking into account the experimental conditions employed in a previous study. Experimental observations concerning carbon deposition in an SOFC operating on glycerol can be explained by the theoretical analysis developed in the present study. Additionally, the effect of mixed electronic-ionic conduction of the electrolyte on carbon deposition at the anode is discussed based on the thermodynamic analysis of the C-O system.

  5. Load shedding equipment minimizing energy expenses at the Berlin-Moabit hospital. Reduzierung von Energiekosten durch Einsatz eines Lastabwurfsystems am Beispiel des Krankenhauses Berlin-Moabit

    Energy Technology Data Exchange (ETDEWEB)

    Baelz, U.

    1989-02-01

    Details are given on a hospital minimizing its energy expenses with the help of load shedding equipment. A description of preliminary analyses (energy flows, unbalanced distribution of loads, recording instruments, peak loads) and the consequences drawn is followed by a presentation of the load shedding equipment selected. Reference is made to the existing electronic computer it is based on. Integrated setpoints deviated as priority groups were disconnected step by step (meshed disconnection of space HVAC systems). The disconnecting times selected insure a quasi-equal thermal comfort during the winter season. Using the load shedding system, annual energy expenses were reduced by 110 000 marks. (HWJ).

  6. Minimal cosmography

    CERN Document Server

    Piazza, Federico

    2015-01-01

    The minimal requirement for cosmography - a nondynamical description of the universe - is a prescription for calculating null geodesics, and timelike geodesics as a function of their proper time. In this paper, we consider the most general linear connection compatible with homogeneity and isotropy, but not necessarily with a metric. A light-cone structure is assigned by choosing a set of geodesics representing light rays. This defines a "scale factor" and a local notion of distance, as that travelled by light in a given proper time interval. We find that the velocities and relativistic energies of free-falling bodies decrease in time as a consequence of cosmic expansion, but at a rate that can be different than that dictated by the usual metric framework. By extrapolating this behavior to photons redshift, we find that the latter is in principle independent of the "scale factor". Interestingly, redshift-distance relations and other standard geometric observables are modified in this extended framework, in a w...

  7. Minimal cosmography

    Science.gov (United States)

    Piazza, Federico; Schücker, Thomas

    2016-04-01

    The minimal requirement for cosmography—a non-dynamical description of the universe—is a prescription for calculating null geodesics, and time-like geodesics as a function of their proper time. In this paper, we consider the most general linear connection compatible with homogeneity and isotropy, but not necessarily with a metric. A light-cone structure is assigned by choosing a set of geodesics representing light rays. This defines a "scale factor" and a local notion of distance, as that travelled by light in a given proper time interval. We find that the velocities and relativistic energies of free-falling bodies decrease in time as a consequence of cosmic expansion, but at a rate that can be different than that dictated by the usual metric framework. By extrapolating this behavior to photons' redshift, we find that the latter is in principle independent of the "scale factor". Interestingly, redshift-distance relations and other standard geometric observables are modified in this extended framework, in a way that could be experimentally tested. An extremely tight constraint on the model, however, is represented by the blackbody-ness of the cosmic microwave background. Finally, as a check, we also consider the effects of a non-metric connection in a different set-up, namely, that of a static, spherically symmetric spacetime.

  8. The method of p-harmonic approximation and optimal interior partial regularity for energy minimizing p-harmonic maps under the controllable growth condition

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    In this paper, we are concerned with the partial regularity for the weak solutions of energy minimizing p-harmonic maps under the controllable growth condition. We get the interior partial regularity by the p-harmonic approximation method together with the technique used to get the decay estimation on some Degenerate elliptic equations and the obstacle problem by Tan and Yan. In particular, we directly get the optimal regularity.

  9. Adding energy minimization strategy to peptide-design algorithm enables better search for RNA-binding peptides: Redesigned λ N peptide binds boxB RNA.

    Science.gov (United States)

    Xiao, Xingqing; Hung, Michelle E; Leonard, Joshua N; Hall, Carol K

    2016-10-15

    Our previously developed peptide-design algorithm was improved by adding an energy minimization strategy which allows the amino acid sidechains to move in a broad configuration space during sequence evolution. In this work, the new algorithm was used to generate a library of 21-mer peptides which could substitute for λ N peptide in binding to boxB RNA. Six potential peptides were obtained from the algorithm, all of which exhibited good binding capability with boxB RNA. Atomistic molecular dynamics simulations were then conducted to examine the ability of the λ N peptide and three best evolved peptides, viz. Pept01, Pept26, and Pept28, to bind to boxB RNA. Simulation results demonstrated that our evolved peptides are better at binding to boxB RNA than the λ N peptide. Sequence searches using the old (without energy minimization strategy) and new (with energy minimization strategy) algorithms confirm that the new algorithm is more effective at finding good RNA-binding peptides than the old algorithm. © 2016 Wiley Periodicals, Inc.

  10. Vertical and adiabatic excitations in anthracene from quantum Monte Carlo: Constrained energy minimization for structural and electronic excited-state properties in the JAGP ansatz

    Science.gov (United States)

    Dupuy, Nicolas; Bouaouli, Samira; Mauri, Francesco; Sorella, Sandro; Casula, Michele

    2015-06-01

    We study the ionization energy, electron affinity, and the π → π∗ (1La) excitation energy of the anthracene molecule, by means of variational quantum Monte Carlo (QMC) methods based on a Jastrow correlated antisymmetrized geminal power (JAGP) wave function, developed on molecular orbitals (MOs). The MO-based JAGP ansatz allows one to rigorously treat electron transitions, such as the HOMO → LUMO one, which underlies the 1La excited state. We present a QMC optimization scheme able to preserve the rank of the antisymmetrized geminal power matrix, thanks to a constrained minimization with projectors built upon symmetry selected MOs. We show that this approach leads to stable energy minimization and geometry relaxation of both ground and excited states, performed consistently within the correlated QMC framework. Geometry optimization of excited states is needed to make a reliable and direct comparison with experimental adiabatic excitation energies. This is particularly important in π-conjugated and polycyclic aromatic hydrocarbons, where there is a strong interplay between low-lying energy excitations and structural modifications, playing a functional role in many photochemical processes. Anthracene is an ideal benchmark to test these effects. Its geometry relaxation energies upon electron excitation are of up to 0.3 eV in the neutral 1La excited state, while they are of the order of 0.1 eV in electron addition and removal processes. Significant modifications of the ground state bond length alternation are revealed in the QMC excited state geometry optimizations. Our QMC study yields benchmark results for both geometries and energies, with values below chemical accuracy if compared to experiments, once zero point energy effects are taken into account.

  11. Vertical and adiabatic excitations in anthracene from quantum Monte Carlo: Constrained energy minimization for structural and electronic excited-state properties in the JAGP ansatz.

    Science.gov (United States)

    Dupuy, Nicolas; Bouaouli, Samira; Mauri, Francesco; Sorella, Sandro; Casula, Michele

    2015-06-07

    We study the ionization energy, electron affinity, and the π → π(∗) ((1)La) excitation energy of the anthracene molecule, by means of variational quantum Monte Carlo (QMC) methods based on a Jastrow correlated antisymmetrized geminal power (JAGP) wave function, developed on molecular orbitals (MOs). The MO-based JAGP ansatz allows one to rigorously treat electron transitions, such as the HOMO → LUMO one, which underlies the (1)La excited state. We present a QMC optimization scheme able to preserve the rank of the antisymmetrized geminal power matrix, thanks to a constrained minimization with projectors built upon symmetry selected MOs. We show that this approach leads to stable energy minimization and geometry relaxation of both ground and excited states, performed consistently within the correlated QMC framework. Geometry optimization of excited states is needed to make a reliable and direct comparison with experimental adiabatic excitation energies. This is particularly important in π-conjugated and polycyclic aromatic hydrocarbons, where there is a strong interplay between low-lying energy excitations and structural modifications, playing a functional role in many photochemical processes. Anthracene is an ideal benchmark to test these effects. Its geometry relaxation energies upon electron excitation are of up to 0.3 eV in the neutral (1)La excited state, while they are of the order of 0.1 eV in electron addition and removal processes. Significant modifications of the ground state bond length alternation are revealed in the QMC excited state geometry optimizations. Our QMC study yields benchmark results for both geometries and energies, with values below chemical accuracy if compared to experiments, once zero point energy effects are taken into account.

  12. Vertical and adiabatic excitations in anthracene from quantum Monte Carlo: Constrained energy minimization for structural and electronic excited-state properties in the JAGP ansatz

    Energy Technology Data Exchange (ETDEWEB)

    Dupuy, Nicolas, E-mail: nicolas.dupuy@impmc.upmc.fr [Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie, Université Pierre et Marie Curie, case 115, 4 place Jussieu, 75252 Paris Cedex 05 (France); Bouaouli, Samira, E-mail: samira.bouaouli@lct.jussieu.fr [Laboratoire de Chimie Théorique, Université Pierre et Marie Curie, case 115, 4 place Jussieu, 75252 Paris Cedex 05 (France); Mauri, Francesco, E-mail: francesco.mauri@impmc.upmc.fr; Casula, Michele, E-mail: michele.casula@impmc.upmc.fr [CNRS and Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie, Université Pierre et Marie Curie, case 115, 4 place Jussieu, 75252 Paris Cedex 05 (France); Sorella, Sandro, E-mail: sorella@sissa.it [International School for Advanced Studies (SISSA), Via Beirut 2-4, 34014 Trieste, Italy and INFM Democritos National Simulation Center, Trieste (Italy)

    2015-06-07

    We study the ionization energy, electron affinity, and the π → π{sup ∗} ({sup 1}L{sub a}) excitation energy of the anthracene molecule, by means of variational quantum Monte Carlo (QMC) methods based on a Jastrow correlated antisymmetrized geminal power (JAGP) wave function, developed on molecular orbitals (MOs). The MO-based JAGP ansatz allows one to rigorously treat electron transitions, such as the HOMO → LUMO one, which underlies the {sup 1}L{sub a} excited state. We present a QMC optimization scheme able to preserve the rank of the antisymmetrized geminal power matrix, thanks to a constrained minimization with projectors built upon symmetry selected MOs. We show that this approach leads to stable energy minimization and geometry relaxation of both ground and excited states, performed consistently within the correlated QMC framework. Geometry optimization of excited states is needed to make a reliable and direct comparison with experimental adiabatic excitation energies. This is particularly important in π-conjugated and polycyclic aromatic hydrocarbons, where there is a strong interplay between low-lying energy excitations and structural modifications, playing a functional role in many photochemical processes. Anthracene is an ideal benchmark to test these effects. Its geometry relaxation energies upon electron excitation are of up to 0.3 eV in the neutral {sup 1}L{sub a} excited state, while they are of the order of 0.1 eV in electron addition and removal processes. Significant modifications of the ground state bond length alternation are revealed in the QMC excited state geometry optimizations. Our QMC study yields benchmark results for both geometries and energies, with values below chemical accuracy if compared to experiments, once zero point energy effects are taken into account.

  13. Monte Carlo-energy minimization of correolide in the Kv1.3 channel: possible role of potassium ion in ligand-receptor interactions

    Directory of Open Access Journals (Sweden)

    Zhorov Boris S

    2007-01-01

    Full Text Available Abstract Background Correolide, a nortriterpene isolated from the Costa Rican tree Spachea correa, is a novel immunosuppressant, which blocks Kv1.3 channels in human T lymphocytes. Earlier mutational studies suggest that correolide binds in the channel pore. Correolide has several nucleophilic groups, but the pore-lining helices in Kv1.3 are predominantly hydrophobic raising questions about the nature of correolide-channel interactions. Results We employed the method of Monte Carlo (MC with energy minimization to search for optimal complexes of correolide in Kv1.2-based models of the open Kv1.3 with potassium binding sites 2/4 or 1/3/5 loaded with K+ ions. The energy was MC-minimized from many randomly generated starting positions and orientations of the ligand. In all the predicted low-energy complexes, oxygen atoms of correolide chelate a K+ ion. Correolide-sensing residues known from mutational analysis along with the ligand-bound K+ ion provide major contributions to the ligand-binding energy. Deficiency of K+ ions in the selectivity filter of C-type inactivated Kv1.3 would stabilize K+-bound correolide in the inner pore. Conclusion Our study explains the paradox that cationic and nucleophilic ligands bind to the same region in the inner pore of K+ channels and suggests that a K+ ion is an important determinant of the correolide receptor and possibly receptors of other nucleophilic blockers of the inner pore of K+ channels.

  14. Exploring structural properties of small carbon clusters Cn (n = 1, 2, 3) using molecular mechanics and energy minimization

    Science.gov (United States)

    Miswan, M. A.; Gopir, G.; Anas, M. M.

    2016-11-01

    Geometry optimization is one of the most widely used methods to study in carbon cluster Cn to understand its structural properties. The total energy for each of the structures was calculated using Octopus software with conjugate gradient Broyden-Fletcher-Goldfarb-Shanno (CG-BFGS). Our calculation and other studies indicate that the linear forms are the most stable structures. However, the C3 isomers have equal probability to form, as the differences in our calculation of total energy are statistically insignificant. Despite there are two cohort of total energy, the calculations are acceptable due to the energy ratio between C3 to C2 and C2 to C1 are comparable to others work. Meanwhile, the bond properties of the C2 and C3 bonds also gives significant difference between our work and previous study.

  15. High-Intensity Discharge Industrial Lighting Design Strategies for the Minimization of Energy Usage and Life-Cycle Cost

    OpenAIRE

    Flory IV, Isaac L.

    2008-01-01

    Worldwide, the electrical energy consumed by artificial lighting is second only to the amount consumed by electric machinery. Of the energy usage attributed to lighting in North America, approximately fifteen percent is consumed by those lighting products that are classified as High-Intensity Discharge (HID). These lighting products, which are dominated by Metal-Halide and High-Pressure Sodium technologies, range in power levels from 35 to 2000 watts and are used in both indoor and outdoor ...

  16. Electrostatic contribution to DNA condensation-application of 'energy minimization' in a simple model in the strong Coulomb coupling regime

    Energy Technology Data Exchange (ETDEWEB)

    Mukherjee, Arup K, E-mail: akmukherjee11@hotmail.com [Department of Physics, Chancellor College, University of Malawi, Box 280, Zomba (Malawi)

    2011-08-17

    The process of bending of straight DNA to a circular form in the presence of any of the mono-, di-, tri- or tetravalent counterions has been simulated in a strong Coulomb coupling environment, employing a previously developed energy minimization simulation technique. The inherent characteristics of the simulation technique allow the monitoring of the required electrostatic contribution to the bending. The curvature of the bending has been found to play a crucial role in facilitating the electrostatic attractive potential energy. The total electrostatic potential energy has been found to decrease with bending, which indicates that bending straight DNA to a circular form or to a toroidal form in the presence of neutralizing counterions is energetically favourable and is practically a spontaneous phenomenon.

  17. Real-space finite-difference approach for multi-body systems: path-integral renormalization group method and direct energy minimization method.

    Science.gov (United States)

    Sasaki, Akira; Kojo, Masashi; Hirose, Kikuji; Goto, Hidekazu

    2011-11-02

    The path-integral renormalization group and direct energy minimization method of practical first-principles electronic structure calculations for multi-body systems within the framework of the real-space finite-difference scheme are introduced. These two methods can handle higher dimensional systems with consideration of the correlation effect. Furthermore, they can be easily extended to the multicomponent quantum systems which contain more than two kinds of quantum particles. The key to the present methods is employing linear combinations of nonorthogonal Slater determinants (SDs) as multi-body wavefunctions. As one of the noticeable results, the same accuracy as the variational Monte Carlo method is achieved with a few SDs. This enables us to study the entire ground state consisting of electrons and nuclei without the need to use the Born-Oppenheimer approximation. Recent activities on methodological developments aiming towards practical calculations such as the implementation of auxiliary field for Coulombic interaction, the treatment of the kinetic operator in imaginary-time evolutions, the time-saving double-grid technique for bare-Coulomb atomic potentials and the optimization scheme for minimizing the total-energy functional are also introduced. As test examples, the total energy of the hydrogen molecule, the atomic configuration of the methylene and the electronic structures of two-dimensional quantum dots are calculated, and the accuracy, availability and possibility of the present methods are demonstrated.

  18. Capacity optimization of battery-generator hybrid power system: Toward minimizing maintenance cost in expeditionary basecamp/operational energy applications

    Science.gov (United States)

    Onwuanumkpe, Jude C.

    Low and transient load condition are known to have deleterious impact on the efficiency and health of diesel generators (DGs). Extensive operation under such loads reduces fuel consumption and energy conversion efficiency, and contribute to diesel engine degradation, damage, or catastrophic failure. Non-ideal loads are prevalent in expeditionary base camps that support contingency operations in austere environments or remote locations where grid electricity is either non-existent or inaccessible. The impact of such loads on DGs exacerbates already overburdened basecamp energy logistics requirements. There is a need, therefore, to eliminate or prevent the occurrence of non-ideal loads. Although advances in diesel engine technologies have improved their performance, DGs remain vulnerable to the consequences of non-ideal loads and inherent inefficiencies of combustion. The mechanisms through which DGs respond to and mitigate non-ideal loads are also mechanically stressful and energy-intensive. Thus, this research investigated the idea of using batteries to prevent DGs from encountering non-ideal loads, as a way to reduce basecamp energy logistics requirements. Using a simple semi-empirical approach, the study modeled and simulated a battery-DG hybrid system under various load conditions. The simulation allowed for synthesis of design space in which specified battery and generator capacity can achieve optimal savings in fuel consumption and maintenance cost. Results show that a right-sized battery-diesel generator system allows for more than 50% cost savings relative to a standalone generator.

  19. A Search for Dilepton Signatures from Minimal Low Energy Supergravity in $\\overline{p}p$ Collisions at $\\sqrt{s} = 1.8 TeV$

    CERN Document Server

    Abbott, B

    2001-01-01

    We report on a search for supersymmetry using the DØ detector. The 1994-96 data sample of $\\sqrt{s}=1.8$ TeV $\\bar{p}p$ collisions was analyzed for events containing two leptons ($e$ or $\\mu$), two or more jets, and missing transverse energy. Assuming minimal supergravity, with free parameters $m_0$, $m_{1/2}$ and $\\tan\\beta$, various thresholds were employed to optimize the search. No excess of events was observed. We present exclusion contours in the $(m_0, m_{1/2})$ plane for $\\tan\\beta=2-6$.

  20. Minimal skin dose increase in longitudinal rotating biplanar linac-MR systems: examination of radiation energy and flattening filter design

    Science.gov (United States)

    Keyvanloo, A.; Burke, B.; St. Aubin, J.; Baillie, D.; Wachowicz, K.; Warkentin, B.; Steciw, S.; Fallone, B. G.

    2016-05-01

    The magnetic fields of linac-MR systems modify the path of contaminant electrons in photon beams, which alters patient entrance skin dose. Also, the increased SSD of linac-MR systems reduces the maximum achievable dose rate. To accurately quantify the changes in entrance skin dose, the authors use EGSnrc Monte Carlo calculations that incorporate 3D magnetic field of the Alberta 0.5 T longitudinal linac-MR system. The Varian 600C linac head geometry assembled on the MRI components is used in the BEAMnrc simulations for 6 MV and 10 MV beam models and skin doses are calculated at an average depth of 70 μm using DOSXYZnrc. 3D modeling shows that magnetic fringe fields decay rapidly and are small at the linac head. SSDs between 100 and 120 cm result in skin-dose increases of between ~6%-19% and ~1%-9% for the 6 and 10 MV beams, respectively. For 6 MV, skin dose increases from ~10.5% to ~1.5% for field-size increases of 5  ×  5 cm2 to 20  ×  20 cm2. For 10 MV, skin dose increases by ~6% for a 5  ×  5 cm2 field, and decreases by ~1.5% for a 20  ×  20 cm2 field. Furthermore, the proposed reshaped flattening filter increases the dose rate from the current 355 MU min-1 to 529 MU min-1 (6 MV) or 604 MU min-1 (10 MV), while the skin-dose increases by only an additional ~2.6% (all percent increases in skin dose are relative to D max). This study suggests that there is minimal increase in the entrance skin dose and minimal/no decrease in the dose rate of the Alberta longitudinal linac-MR system. The even lower skin dose increase at 10 MV offers further advantages in future designs of linac-MR prototypes.

  1. Strategies to enhance waste minimization and energy conservation within organizations: a case study from the UK construction sector.

    Science.gov (United States)

    Jones, Jo; Jackson, Janet; Tudor, Terry; Bates, Margaret

    2012-09-01

    Strategies for enhancing environmental management are a key focus for the government in the UK. Using a manufacturing company from the construction sector as a case study, this paper evaluates selected interventionist techniques, including environmental teams, awareness raising and staff training to improve environmental performance. The study employed a range of methods including questionnaire surveys and audits of energy consumption and generation of waste to examine the outcomes of the selected techniques. The results suggest that initially environmental management was not a focus for either the employees or the company. However, as a result of employing the techniques, the company was able to reduce energy consumption, increase recycling rates and achieve costs savings in excess of £132,000.

  2. Minimization of the energy storage requirements of a stand-alone wind power installation by means of photovoltaic panels

    Energy Technology Data Exchange (ETDEWEB)

    Kaldellis, J.K.; Kostas, P. [TEI Piraeus, Mechanical Engineering Dept., Athens (Greece); Filios, A. [School of Pedagogical and Technological Education, Fluid Mechanics and Turbomachines Lab., Athens (Greece)

    2006-07-01

    Autonomous wind power systems are among the most interesting and environmentally friendly technological solutions for the electrification of remote consumers. In many cases, however, the battery contribution to the initial or the total operational cost is found to be dominant, discouraging further penetration of the available wind resource. This is basically the case for areas possessing a medium-low wind potential. On the other hand, several isolated consumers are located in regions having the regular benefit of an abundant and reliable solar energy supply. In this context the present study investigates the possibility of reducing the battery size of a stand-alone wind power installation by incorporating a small photovoltaic generator. For this purpose an integrated energy production installation based exclusively on renewable energy resources is hereby proposed. Subsequently a new numerical algorithm is developed that is able to estimate the appropriate dimensions of a similar system. According to the results obtained by long-term experimental measurements, the introduction of the photovoltaic panels considerably improves the operational and financial behaviour of the complete installation owing to the imposed significant battery capacity diminution. (Author)

  3. Minimization of the energy storage requirements of a stand-alone wind power installation by means of photovoltaic panels

    Science.gov (United States)

    Kaldellis, J. K.; Kostas, P.; Filios, A.

    2006-07-01

    Autonomous wind power systems are among the most interesting and environmentally friendly technological solutions for the electrification of remote consumers. In many cases, however, the battery contribution to the initial or the total operational cost is found to be dominant, discouraging further penetration of the available wind resource. This is basically the case for areas possessing a medium-low wind potential. On the other hand, several isolated consumers are located in regions having the regular benefit of an abundant and reliable solar energy supply. In this context the present study investigates the possibility of reducing the battery size of a stand-alone wind power installation by incorporating a small photovoltaic generator. For this purpose an integrated energy production installation based exclusively on renewable energy resources is hereby proposed. Subsequently a new numerical algorithm is developed that is able to estimate the appropriate dimensions of a similar system. According to the results obtained by long-term experimental measurements, the introduction of the photovoltaic panels considerably improves the operational and financial behaviour of the complete installation owing to the imposed significant battery capacity diminution. Copyright

  4. The Minimal Matching Energy of Unicyclic Graphs of a Given Diameter%给定直径的单圈图的极小匹配能量

    Institute of Scientific and Technical Information of China (English)

    吴倩倩; 李红海

    2015-01-01

    图的匹配能量定义为该图的匹配多项式的零点的绝对值之和。设U( n,d)为n阶且直径为d的连通单圈图的集合,刻画了U( n,d)中取到极小匹配能量的极图。%The matching energy of a graph was defined as the sum of the absolute values of zeros of its matching pol-ynomial. Let U( n,d)be the set of connected unicyclic graphs of order n and diameter d,the graph from U( n,d) minimizing the matching energy is completely characterized.

  5. Decision support system on line to minimize the NO{sub x} emission. Results from Oerebro Energi; Beslutsstoed on line foer minimering av NO{sub x}. Resultat fraan Oerebro Energi

    Energy Technology Data Exchange (ETDEWEB)

    Bergdahl, B.G.; Liao, B.; Sieurin, J. [EuroSim AB, Nykoeping (Sweden)

    1996-05-01

    A Decision Support System to reduce NO{sub x} emission from combustion processes with SNCR system have been developed and tested in full scale at Oerebro Energy. The boiler is a 165 MWh{sub th} CFB and have been fired with a mixture of biomass, peat and coal. The results proves that the EuroSim method works to calculate the derivative included in the Decision Support System. The Decision Support System is a tool for the operator of the plant, he will be informed of the advantage of making an increase or decrease of the ammonia flow or excess air. The trend curves that are presented to the operator includes information about the economic value to make an adjustment of the ammonia flow. The derivative dNO{sub x}/dO{sub 2} shows the advantage of making a reduction in the excess air level, concerning the fee for NO{sub x}. In this case it is important to take into consideration the risk for understoichiometric combustion and corrosion. The results from the full scale test in the Oerebro Plant shows that during some time periods it is economical to shut off the ammonia flow. The derivative dNO{sub x}/dAF is under the profitability limit. This indicate that the cost for the ammonia is higher than the fee for the NO{sub x} emission. If the ammonia flow is added in excess, the emission of ammonia and N{sub 2}O will increase. During other time periods the Decision Support System shows that it is profitable to increase the ammonia flow, the derivative is lower than -0,2. The derivative dNO{sub x}/dO{sub 2} is normally between 10 and 20 (ppm/%). This indicate that it is a great potential to reduce the NO{sub x} fee by decreasing the excess air level in the boiler. 3 refs, 23 figs

  6. Optimal Control Method for Wind Farm to Support Temporary Primary Frequency Control with Minimized Wind Energy Cost

    DEFF Research Database (Denmark)

    Wang, Haijiao; Chen, Zhe; Jiang, Quanyuan

    2015-01-01

    This study proposes an optimal control method for variable speed wind turbines (VSWTs) based wind farm (WF) to support temporary primary frequency control. This control method consists of two layers: temporary frequency support control (TFSC) of the VSWT, and temporary support power optimal...... dispatch (TSPOD) of the WF. With TFSC, the VSWT could temporarily provide extra power to support system frequency under varying and wide-range wind speed. In the WF control centre, TSPOD optimally dispatches the frequency support power orders to the VSWTs that operate under different wind speeds, minimises...... the wind energy cost of frequency support, and satisfies the support capabilities of the VSWTs. The effectiveness of the whole control method is verified in the IEEE-RTS built in MATLABSimulink, and compared with a published de-loading method....

  7. A chord error conforming tool path B-spline fitting method for NC machining based on energy minimization and LSPIA

    Directory of Open Access Journals (Sweden)

    Shanshan He

    2015-10-01

    Full Text Available Piecewise linear (G01-based tool paths generated by CAM systems lack G1 and G2 continuity. The discontinuity causes vibration and unnecessary hesitation during machining. To ensure efficient high-speed machining, a method to improve the continuity of the tool paths is required, such as B-spline fitting that approximates G01 paths with B-spline curves. Conventional B-spline fitting approaches cannot be directly used for tool path B-spline fitting, because they have shortages such as numerical instability, lack of chord error constraint, and lack of assurance of a usable result. Progressive and Iterative Approximation for Least Squares (LSPIA is an efficient method for data fitting that solves the numerical instability problem. However, it does not consider chord errors and needs more work to ensure ironclad results for commercial applications. In this paper, we use LSPIA method incorporating Energy term (ELSPIA to avoid the numerical instability, and lower chord errors by using stretching energy term. We implement several algorithm improvements, including (1 an improved technique for initial control point determination over Dominant Point Method, (2 an algorithm that updates foot point parameters as needed, (3 analysis of the degrees of freedom of control points to insert new control points only when needed, (4 chord error refinement using a similar ELSPIA method with the above enhancements. The proposed approach can generate a shape-preserving B-spline curve. Experiments with data analysis and machining tests are presented for verification of quality and efficiency. Comparisons with other known solutions are included to evaluate the worthiness of the proposed solution.

  8. Validation of Five Minimally Obstructive Methods to Estimate Physical Activity Energy Expenditure in Young Adults in Semi-Standardized Settings

    Directory of Open Access Journals (Sweden)

    Mikkel B. Schneller

    2015-03-01

    Full Text Available We compared the accuracy of five objective methods, including two newly developed methods combining accelerometry and activity type recognition (Acti4, against indirect calorimetry, to estimate total energy expenditure (EE of different activities in semi-standardized settings. Fourteen participants performed a standardized and semi-standardized protocol including seven daily life activity types, while having their EE measured by indirect calorimetry. Simultaneously, physical activity was quantified by an ActivPAL3, two ActiGraph GT3X+’s and an Actiheart. EE was estimated by the standard ActivPAL3 software (ActivPAL, ActiGraph GT3X+ (ActiGraph and Actiheart (Actiheart, and by a combination of activity type recognition via Acti4 software and activity counts per minute (CPM of either a hip- or thigh-worn ActiGraph GT3X+ (AGhip + Acti4 and AGthigh + Acti4. At group level, estimated physical activities EE by Actiheart (MSE = 2.05 and AGthigh + Acti4 (MSE = 0.25 were not significantly different from measured EE by indirect calorimetry, while significantly underestimated by ActiGraph, ActivPAL and AGhip + Acti4. AGthigh + Acti4 and Actiheart explained 77% and 45%, of the individual variations in measured physical activity EE by indirect calorimetry, respectively. This study concludes that combining accelerometer data from a thigh-worn ActiGraph GT3X+ with activity type recognition improved the accuracy of activity specific EE estimation against indirect calorimetry in semi-standardized settings compared to previously validated methods using CPM only.

  9. Minimal Standard Model self-energies at finite temperature in the presence of weak magnetic fields: towards a full symmetry restoration study

    CERN Document Server

    Tejeda-Yeomans, Maria E; Sanchez, Angel; Piccinelli, Gabriella; Ayala, Alejandro

    2008-01-01

    The study of the universe's primordial plasma at high temperature plays an important role when tackling different questions in cosmology, such as the origin of the matter-antimatter asymmetry. In the Minimal Standard Model (MSM) neither the amount of CP violation nor the strength of the phase transition are enough to produce and preserve baryon number during the Electroweak Phase Transition (EWPT), which are two of the three ingredients needed to develop baryon asymmetry. In this talk we present the first part of the analysis done within a scenario where it is viable to have improvements to the aforementioned situation: we work with the degrees of freedom in the broken symmetry phase of the MSM and analyze the development of the EWPT in the presence of a weak magnetic field. More specifically, we calculate the particle self-energies that include the effects of the weak magnetic field, needed for the MSM effective potential up to ring diagrams.

  10. Search for dilepton signatures from minimal low-energy supergravity in pp¯ collisions at s=1.8 TeV

    Science.gov (United States)

    Abbott, B.; Abolins, M.; Abramov, V.; Acharya, B. S.; Adams, D. L.; Adams, M.; Alves, G. A.; Amos, N.; Anderson, E. W.; Baarmand, M. M.; Babintsev, V. V.; Babukhadia, L.; Baden, A.; Baldin, B.; Balm, P. W.; Banerjee, S.; Bantly, J.; Barberis, E.; Baringer, P.; Bartlett, J. F.; Bassler, U.; Bean, A.; Begel, M.; Belyaev, A.; Beri, S. B.; Bernardi, G.; Bertram, I.; Besson, A.; Bezzubov, V. A.; Bhat, P. C.; Bhatnagar, V.; Bhattacharjee, M.; Blazey, G.; Blessing, S.; Boehnlein, A.; Bojko, N. I.; Borcherding, F.; Brandt, A.; Breedon, R.; Briskin, G.; Brock, R.; Brooijmans, G.; Bross, A.; Buchholz, D.; Buehler, M.; Buescher, V.; Burtovoi, V. S.; Butler, J. M.; Canelli, F.; Carvalho, W.; Casey, D.; Casilum, Z.; Castilla-Valdez, H.; Chakraborty, D.; Chan, K. M.; Chekulaev, S. V.; Cho, D. K.; Choi, S.; Chopra, S.; Choudhary, B. C.; Christenson, J. H.; Chung, M.; Claes, D.; Clark, A. R.; Cochran, J.; Coney, L.; Connolly, B.; Cooper, W. E.; Coppage, D.; Cummings, M. A.; Cutts, D.; Dahl, O. I.; Davis, G. A.; Davis, K.; de, K.; del Signore, K.; Demarteau, M.; Demina, R.; Demine, P.; Denisov, D.; Denisov, S. P.; Desai, S.; Diehl, H. T.; Diesburg, M.; di Loreto, G.; Doulas, S.; Draper, P.; Ducros, Y.; Dudko, L. V.; Duensing, S.; Dugad, S. R.; Dyshkant, A.; Edmunds, D.; Ellison, J.; Elvira, V. D.; Engelmann, R.; Eno, S.; Eppley, G.; Ermolov, P.; Eroshin, O. V.; Estrada, J.; Evans, H.; Evdokimov, V. N.; Fahland, T.; Feher, S.; Fein, D.; Ferbel, T.; Fisk, H. E.; Fisyak, Y.; Flattum, E.; Fleuret, F.; Fortner, M.; Frame, K. C.; Fuess, S.; Gallas, E.; Galyaev, A. N.; Gartung, P.; Gavrilov, V.; Genik, R. J.; Genser, K.; Gerber, C. E.; Gershtein, Y.; Gibbard, B.; Gilmartin, R.; Ginther, G.; Gómez, B.; Gómez, G.; Goncharov, P. I.; González Solís, J. L.; Gordon, H.; Goss, L. T.; Gounder, K.; Goussiou, A.; Graf, N.; Graham, G.; Grannis, P. D.; Green, J. A.; Greenlee, H.; Grinstein, S.; Grudberg, P.; Grünendahl, S.; Gupta, A.; Gurzhiev, S. N.; Gutierrez, G.; Gutierrez, P.; Hadley, N. J.; Haggerty, H.; Hagopian, S.; Hagopian, V.; Hahn, K. S.; Hall, R. E.; Hanlet, P.; Hansen, S.; Hauptman, J. M.; Hays, C.; Hebert, C.; Hedin, D.; Heinson, A. P.; Heintz, U.; Heuring, T.; Hirosky, R.; Hobbs, J. D.; Hoeneisen, B.; Hoftun, J. S.; Hou, S.; Huang, Y.; Ito, A. S.; Jerger, S. A.; Jesik, R.; Johns, K.; Johnson, M.; Jonckheere, A.; Jones, M.; Jöstlein, H.; Juste, A.; Kahn, S.; Kajfasz, E.; Karmanov, D.; Karmgard, D.; Kehoe, R.; Kim, S. K.; Klima, B.; Klopfenstein, C.; Knuteson, B.; Ko, W.; Kohli, J. M.; Kostritskiy, A. V.; Kotcher, J.; Kotwal, A. V.; Kozelov, A. V.; Kozlovsky, E. A.; Krane, J.; Krishnaswamy, M. R.; Krzywdzinski, S.; Kubantsev, M.; Kuleshov, S.; Kulik, Y.; Kunori, S.; Kuznetsov, V. E.; Landsberg, G.; Leflat, A.; Lehner, F.; Li, J.; Li, Q. Z.; Lima, J. G.; Lincoln, D.; Linn, S. L.; Linnemann, J.; Lipton, R.; Lucotte, A.; Lueking, L.; Lundstedt, C.; Maciel, A. K.; Madaras, R. J.; Manankov, V.; Mani, S.; Mao, H. S.; Marshall, T.; Martin, M. I.; Martin, R. D.; Mauritz, K. M.; May, B.; Mayorov, A. A.; McCarthy, R.; McDonald, J.; McMahon, T.; Melanson, H. L.; Meng, X. C.; Merkin, M.; Merritt, K. W.; Miao, C.; Miettinen, H.; Mihalcea, D.; Mincer, A.; Mishra, C. S.; Mokhov, N.; Mondal, N. K.; Montgomery, H. E.; Mostafa, M.; da Motta, H.; Nagy, E.; Nang, F.; Narain, M.; Narasimham, V. S.; Neal, H. A.; Negret, J. P.; Negroni, S.; Norman, D.; Oesch, L.; Oguri, V.; Olivier, B.; Oshima, N.; Padley, P.; Pan, L. J.; Para, A.; Parashar, N.; Partridge, R.; Parua, N.; Paterno, M.; Patwa, A.; Pawlik, B.; Perkins, J.; Peters, M.; Peters, O.; Piegaia, R.; Piekarz, H.; Pope, B. G.; Popkov, E.; Prosper, H. B.; Protopopescu, S.; Qian, J.; Quintas, P. Z.; Raja, R.; Rajagopalan, S.; Ramberg, E.; Rapidis, P.; Reay, N. W.; Reucroft, S.; Rha, J.; Rijssenbeek, M.; Rockwell, T.; Roco, M.; Rubinov, P.; Ruchti, R.; Rutherfoord, J.; Santoro, A.; Sawyer, L.; Schamberger, R. D.; Schellman, H.; Schwartzman, A.; Sculli, J.; Sen, N.; Shabalina, E.; Shankar, H. C.; Shivpuri, R. K.; Shpakov, D.; Shupe, M.; Sidwell, R. A.; Simak, V.; Singh, H.; Singh, J. B.; Sirotenko, V.; Slattery, P.; Smith, E.; Smith, R. P.; Snihur, R.; Snow, G. R.; Snow, J.; Snyder, S.; Solomon, J.; Sorín, V.; Sosebee, M.; Sotnikova, N.; Soustruznik, K.; Souza, M.; Stanton, N. R.; Steinbrück, G.; Stephens, R. W.; Stevenson, M. L.; Stichelbaut, F.; Stoker, D.; Stolin, V.; Stoyanova, D. A.; Strauss, M.; Streets, K.; Strovink, M.; Stutte, L.; Sznajder, A.; Taylor, W.; Tentindo-Repond, S.; Thompson, J.; Toback, D.; Trippe, T. G.; Turcot, A. S.; Tuts, P. M.; van Gemmeren, P.; Vaniev, V.; van Kooten, R.; Varelas, N.; Volkov, A. A.; Vorobiev, A. P.; Wahl, H. D.; Wang, H.; Wang, Z.-M.; Warchol, J.; Watts, G.; Wayne, M.; Weerts, H.; White, A.; White, J. T.; Whiteson, D.; Wightman, J. A.; Wijngaarden, D. A.; Willis, S.; Wimpenny, S. J.; Wirjawan, J. V.; Womersley, J.; Wood, D. R.; Yamada, R.; Yamin, P.; Yasuda, T.; Yip, K.; Youssef, S.; Yu, J.; Yu, Z.; Zanabria, M.; Zheng, H.; Zhou, Z.; Zhu, Z. H.; Zielinski, M.; Zieminska, D.; Zieminski, A.; Zutshi, V.; Zverev, E. G.; Zylberstejn, A.

    2001-05-01

    We report on a search for supersymmetry using the DØ detector. The 1994-1996 data sample of s=1.8 TeV pp¯ collisions was analyzed for events containing two leptons (e or μ), two or more jets, and missing transverse energy. Assuming the minimal supergravity model, with A0=0 and μ<0, various thresholds were employed to optimize the search. No events were found beyond expectation from the background. We set a lower limit at the 95% C.L. of 255 GeV/c2 for equal mass squarks and gluinos for tan β=2, and present exclusion contours in the (m0,m1/2) plane for tan β=2-6.

  11. 一种新颖的基于FGS的发射能量最小化算法%A novel transmission energy minimization algorithm based on fine granularity scalability

    Institute of Scientific and Technical Information of China (English)

    吴彪; 张颖; 张兆扬

    2006-01-01

    This paper proposes an optimal solution to choose the number of enhancement layers in fine granularity scalability (FGS) scheme under the constraint of minimum transmission energy, in which FGS is combined with transmission energy control, so that FGS enhancement layer transmission energy is minimized while the distortion guaranteed. By changing the bit-plane level and packet loss rate, minimum transmission energy of enhancement layer is obtained, while the expected distortion is satisfied.

  12. Minimization of energy consumption in ad hoc networks; Minimisation de la consommation d'energie dans les reseaux ad hoc

    Energy Technology Data Exchange (ETDEWEB)

    Senouci, S.M.; Pujolle, G. [Paris-6 Univ., Lab. LIP6, 75 (France)

    2005-04-01

    An ad hoc network is a collection of wireless devices forming a temporary network independently of any administration or fixed infrastructure. The main benefits of this new generation of mobile networks are flexibility and their low cost. Wireless devices have maximum utility when they can be used 'anywhere at anytime'. However, one of the greatest limitations to that goal is the finite power supplies. Since batteries provide limited power, a general constraint of wireless communication is the short continuous operation time of mobile terminals. This constraint is more important for the ad hoc networks, since every terminal has to perform the functions of a router. Therefore, energy consumption should be a crucial issue while designing new communication protocols and particularly ad hoc routing protocols. We propose, in this paper, some extensions to the most important on-demand routing algorithm, AODV (Ad hoc On demand Distance Vector). The discovery mechanism in these extensions uses energy as a routing metric. These algorithms improve the network survivability by maintaining the network connectivity, which is the strong requirement for a high-quality communication. They carry out this objective with low message overhead for computing routes and without affecting the other network protocol layers. (authors)

  13. Practical examples of energy-saving and pollution minimization of dyeing processes%节能减排染色工艺实例解析

    Institute of Scientific and Technical Information of China (English)

    赵利强

    2011-01-01

    Various dyeing processes with energy-saving and pollution minimization ara introduced, including cold pad-batch pretreatment , enzyme batching pretreatment, pigment dyeing , indanthrene leuco dyeing, continuous pad-steam dyeing with reactive dyes, as well as sulfur dyeing requiring no mercerization.Color fastness and process costs between the traditional process and the energy conserving processes are compared.%介绍了冷轧堆、酶堆前处理工艺、涂料染色、士林隐色体染色、活性染料轧蒸连续染色、无需丝光的短流程硫化染料染色等节能减排的染色工艺及操作注意事项;分析比较了传统染色工艺和短流程节能减排染色工艺的产品的染色牢度指标,以及各种工艺的生产成本.

  14. Development of a commercial building/site evaluation framework for minimizing energy consumption and greenhouse gas emissions of transportation and building systems

    Science.gov (United States)

    Weigel, Brent A.

    In urbanized areas, building and transportation systems generally comprise the majority of energy consumption and greenhouse gas (GHG) emissions. Realization of global environmental sustainability depends upon efficiency improvements of building and transportation systems in the built environment. The selection of efficient buildings and locations can help to improve the efficient utilization of transportation and building systems. Green building design and rating frameworks provide some guidance and incentive for the development of more efficient building and transportation systems. However, current frameworks are based primarily on prescriptive, component standards, rather than performance-based, whole-building evaluations. This research develops a commercial building/site evaluation framework for the minimization of energy consumption and GHG emissions of transportation and building systems through building/site selection. The framework examines, under uncertainty, multiple dimensions of building/site operation efficiencies: transportation access to/from a building site; heating, ventilation, air conditioning, and domestic hot water; interior and exterior lighting; occupant conveyances; and energy supply. With respect to transportation systems, the framework leverages regional travel demand model data to estimate the activity associated with home-based work and non-homebased work trips. A Monte Carlo simulation approach is used to quantify the dispersion in the estimated trip distances, travel times, and mode choice. The travel activity estimates are linked with a variety of existing calculation resources for quantifying energy consumption and GHG emissions. With respect to building systems, the framework utilizes a building energy simulation approach to estimate energy consumption and GHG emissions. The building system calculation procedures include a sensitivity analysis and Monte Carlo analysis to account for the impacts of input parameter uncertainty on

  15. Numerical models based on a minimal set of sarcolemmal electrogenic proteins and an intracellular Ca(2+) clock generate robust, flexible, and energy-efficient cardiac pacemaking.

    Science.gov (United States)

    Maltsev, Victor A; Lakatta, Edward G

    2013-06-01

    Recent evidence supports the idea that robust and, importantly, FLEXIBLE automaticity of cardiac pacemaker cells is conferred by a coupled system of membrane ion currents (an "M-clock") and a sarcoplasmic reticulum (SR)-based Ca(2+) oscillator ("Ca(2+)clock") that generates spontaneous diastolic Ca(2+) releases. This study identified numerical models of a human biological pacemaker that features robust and flexible automaticity generated by a minimal set of electrogenic proteins and a Ca(2+)clock. Following the Occam's razor principle (principle of parsimony), M-clock components of unknown molecular origin were excluded from Maltsev-Lakatta pacemaker cell model and thirteen different model types of only 4 or 5 components were derived and explored by a parametric sensitivity analysis. The extended ranges of SR Ca(2+) pumping (i.e. Ca(2+)clock performance) and conductance of ion currents were sampled, yielding a large variety of parameter combination, i.e. specific model sets. We tested each set's ability to simulate autonomic modulation of human heart rate (minimum rate of 50 to 70bpm; maximum rate of 140 to 210bpm) in response to stimulation of cholinergic and β-adrenergic receptors. We found that only those models that include a Ca(2+)clock (including the minimal 4-parameter model "ICaL+IKr+INCX+Ca(2+)clock") were able to reproduce the full range of autonomic modulation. Inclusion of If or ICaT decreased the flexibility, but increased the robustness of the models (a relatively larger number of sets did not fail during testing). The new models comprised of components with clear molecular identity (i.e. lacking IbNa & Ist) portray a more realistic pacemaking: A smaller Na(+) influx is expected to demand less energy for Na(+) extrusion. The new large database of the reduced coupled-clock numerical models may serve as a useful tool for the design of biological pacemakers. It will also provide a conceptual basis for a general theory of robust, flexible, and energy

  16. Numerical models based on a minimal set of sarcolemmal electrogenic proteins and an intracellular Ca2+ clock generate robust, flexible, and energy-efficient cardiac pacemaking

    Science.gov (United States)

    Maltsev, Victor A.; Lakatta, Edward G.

    2015-01-01

    Recent evidence supports the idea that robust and, importantly, FLEXIBLE automaticity of cardiac pacemaker cells is conferred by a coupled system of membrane ion currents (an “M-clock”) and a sarcoplasmic reticulum (SR)-based Ca2+ oscillator (“Ca2+clock”) that generates spontaneous diastolic Ca2+ releases. This study identified numerical models of a human biological pacemaker that features robust and flexible automaticity generated by a minimal set of electrogenic proteins and a Ca2+clock. Following the Occam’s razor principle (principle of parsimony), M-clock components of unknown molecular origin were excluded from Maltsev-Lakatta pacemaker cell model and thirteen different model types of only 4 or 5 components were derived and explored by a parametric sensitivity analysis. The extended ranges of SR Ca2+ pumping (i.e. Ca2+clock performance) and conductance of ion currents were sampled, yielding a large variety of parameter combination, i.e. specific model sets. We tested each set’s ability to simulate autonomic modulation of human heart rate (minimum rate of 50 to 70 bpm; maximum rate of 140 to 210 bpm) in response to stimulation of cholinergic and β-adrenergic receptors. We found that only those models that include a Ca2+clock (including the minimal 4-parameter model “ICaL+IKr+INCX+Ca2+clock”) were able to reproduce the full range of autonomic modulation. Inclusion of If or ICaT decreased the flexibility, but increased the robustness of the models (a relatively larger number of sets did not fail during testing). The new models comprised of components with clear molecular identity (i.e. lacking IbNa & Ist) portray a more realistic pacemaking: A smaller Na+ influx is expected to demand less energy for Na+ extrusion. The new large database of the reduced coupled-clock numerical models may serve as a useful tool for the design of biological pacemakers. It will also provide a conceptual basis for a general theory of robust, flexible, and energy

  17. Minimally Invasive Dentistry

    Science.gov (United States)

    ... to your desktop! more... What Is Minimally Invasive Dentistry? Article Chapters What Is Minimally Invasive Dentistry? Minimally ... techniques. Reviewed: January 2012 Related Articles: Minimally Invasive Dentistry Minimally Invasive Veneers Dramatically Change Smiles What Patients ...

  18. Wetting and Minimal Surfaces

    CERN Document Server

    Bachas, C; Wiese, K J; Bachas, Constantin; Doussal, Pierre Le; Wiese, Kay Joerg

    2006-01-01

    We study minimal surfaces which arise in wetting and capillarity phenomena. Using conformal coordinates, we reduce the problem to a set of coupled boundary equations for the contact line of the fluid surface, and then derive simple diagrammatic rules to calculate the non-linear corrections to the Joanny-de Gennes energy. We argue that perturbation theory is quasi-local, i.e. that all geometric length scales of the fluid container decouple from the short-wavelength deformations of the contact line. This is illustrated by a calculation of the linearized interaction between contact lines on two opposite parallel walls. We present a simple algorithm to compute the minimal surface and its energy based on these ideas. We also point out the intriguing singularities that arise in the Legendre transformation from the pure Dirichlet to the mixed Dirichlet-Neumann problem.

  19. Minimal Walking Technicolor

    DEFF Research Database (Denmark)

    Frandsen, Mads Toudal

    2007-01-01

    I report on our construction and analysis of the effective low energy Lagrangian for the Minimal Walking Technicolor (MWT) model. The parameters of the effective Lagrangian are constrained by imposing modified Weinberg sum rules and by imposing a value for the S parameter estimated from the under...... the underlying Technicolor theory. The constrained effective Lagrangian allows for an inverted vector vs. axial-vector mass spectrum in a large part of the parameter space....

  20. "Neuro-semeiotics" and "free-energy minimization" suggest a unified perspective for integrative brain actions: focus on receptor heteromers and Roamer type of volume transmission.

    Science.gov (United States)

    Agnati, Luigi F; Guidolin, Diego; Marcoli, Manuela; Genedani, Susanna; Borroto-Escuela, Dasiel; Maura, Guido; Fuxe, Kjell

    2014-01-01

    Two far-reaching theoretical approaches, namely "Neuro-semeiotics" (NS) and "Free-energy Minimization" (FEM), have been recently proposed as frames within which to put forward heuristic hypotheses on integrative brain actions. In the present paper these two theoretical approaches are briefly discussed in the perspective of a recent model of brain architecture and information handling based on what we suggest calling Jacob's tinkering principle, whereby "to create is to recombine!". The NS and FEM theoretical approaches will be discussed from the perspective both of the Roamer-Type Volume Transmission (especially exosome-mediated) of intercellular communication and of the impact of receptor oligomers and Receptor-Receptor Interactions (RRIs) on signal recognition/decoding processes. In particular, the Bio-semeiotics concept of "adaptor" will be used to analyze RRIs as an important feature of NS. Furthermore, the concept of phenotypic plasticity of cells will be introduced in view of the demonstration of the possible transfer of receptors (i.e., adaptors) into a computational network via exosomes (see also Appendix). Thus, Jacob's tinkering principle will be proposed as a theoretical basis for some learning processes both at the network level (Turing-like type of machine) and at the molecular level as a consequence of both the plastic changes in the adaptors caused by the allosteric interactions in the receptor oligomers and the intercellular transfer of receptors. Finally, on the basis of NS and FEM theories, a unified perspective for integrative brain actions will be proposed.

  1. A step by step selection method for the location and the size of a waste-to-energy facility targeting the maximum output energy and minimization of gate fee.

    Science.gov (United States)

    Kyriakis, Efstathios; Psomopoulos, Constantinos; Kokkotis, Panagiotis; Bourtsalas, Athanasios; Themelis, Nikolaos

    2017-06-23

    This study attempts the development of an algorithm in order to present a step by step selection method for the location and the size of a waste-to-energy facility targeting the maximum output energy, also considering the basic obstacle which is in many cases, the gate fee. Various parameters identified and evaluated in order to formulate the proposed decision making method in the form of an algorithm. The principle simulation input is the amount of municipal solid wastes (MSW) available for incineration and along with its net calorific value are the most important factors for the feasibility of the plant. Moreover, the research is focused both on the parameters that could increase the energy production and those that affect the R1 energy efficiency factor. Estimation of the final gate fee is achieved through the economic analysis of the entire project by investigating both expenses and revenues which are expected according to the selected site and outputs of the facility. In this point, a number of commonly revenue methods were included in the algorithm. The developed algorithm has been validated using three case studies in Greece-Athens, Thessaloniki, and Central Greece, where the cities of Larisa and Volos have been selected for the application of the proposed decision making tool. These case studies were selected based on a previous publication made by two of the authors, in which these areas where examined. Results reveal that the development of a «solid» methodological approach in selecting the site and the size of waste-to-energy (WtE) facility can be feasible. However, the maximization of the energy efficiency factor R1 requires high utilization factors while the minimization of the final gate fee requires high R1 and high metals recovery from the bottom ash as well as economic exploitation of recovered raw materials if any.

  2. Logarithmic Superconformal Minimal Models

    CERN Document Server

    Pearce, Paul A; Tartaglia, Elena

    2013-01-01

    The higher fusion level logarithmic minimal models LM(P,P';n) have recently been constructed as the diagonal GKO cosets (A_1^{(1)})_k oplus (A_1^{(1)})_n / (A_1^{(1)})_{k+n} where n>0 is an integer fusion level and k=nP/(P'-P)-2 is a fractional level. For n=1, these are the logarithmic minimal models LM(P,P'). For n>1, we argue that these critical theories are realized on the lattice by n x n fusion of the n=1 models. For n=2, we call them logarithmic superconformal minimal models LSM(p,p') where P=|2p-p'|, P'=p' and p,p' are coprime, and they share the central charges of the rational superconformal minimal models SM(P,P'). Their mathematical description entails the fused planar Temperley-Lieb algebra which is a spin-1 BMW tangle algebra with loop fugacity beta_2=x^2+1+x^{-2} and twist omega=x^4 where x=e^{i(p'-p)pi/p'}. Examples are superconformal dense polymers LSM(2,3) with c=-5/2, beta_2=0 and superconformal percolation LSM(3,4) with c=0, beta_2=1. We calculate the free energies analytically. By numerical...

  3. Minimal Composite Inflation

    DEFF Research Database (Denmark)

    Channuie, Phongpichit; Jark Joergensen, Jakob; Sannino, Francesco

    2011-01-01

    We investigate models in which the inflaton emerges as a composite field of a four dimensional, strongly interacting and nonsupersymmetric gauge theory featuring purely fermionic matter. We show that it is possible to obtain successful inflation via non-minimal coupling to gravity, and that the u......We investigate models in which the inflaton emerges as a composite field of a four dimensional, strongly interacting and nonsupersymmetric gauge theory featuring purely fermionic matter. We show that it is possible to obtain successful inflation via non-minimal coupling to gravity......, and that the underlying dynamics is preferred to be near conformal. We discover that the compositeness scale of inflation is of the order of the grand unified energy scale....

  4. Minimal Higgs inflation

    CERN Document Server

    Maity, Debaprasad

    2016-01-01

    In this paper we propose two simple minimal Higgs inflation scenarios through a simple modification of the Higgs potential, as opposed to the usual non-minimal Higgs-gravity coupling prescription. The modification is done in such a way that it creates a flat plateau for a huge range of field values at the inflationary energy scale $\\mu \\simeq (\\lambda)^{1/4} \\alpha$. Assuming the perturbative Higgs quartic coupling, $\\lambda \\simeq {\\cal O}(1)$, for both the models inflation energy scale turned out to be $\\mu \\simeq (10^{14}, 10^{15})$ GeV, and prediction of all the cosmologically relevant quantities, $(n_s,r,dn_s^k)$, fit extremely well with observations made by PLANCK. Considering observed central value of the scalar spectral index, $n_s= 0.968$, our two models predict efolding number, $N = (52,47)$. Within a wide range of viable parameter space, we found that the prediction of tensor to scalar ratio $r (\\leq 10^{-5})$ is far below the current experimental sensitivity to be observed in the near future. The ...

  5. Eleventh annual Department of Energy low-level waste management conference. Volume 3: Waste characterization, waste reduction and minimization, prototype licensing application

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1989-11-01

    Thirteen papers are presented in volume 3. The seven papers on waste characterization discuss sampling, analysis, and certification techniques for low-level radioactive wastes. Three papers discuss US DOE waste minimization policies and regulations, Y-12 Plant`s reduction of chlorinated solvents, and C-14 removal from spent resins. The last three papers discuss the licensing studies for earth-mounded concrete bunkers for LLW disposal. Papers have been processed separately for inclusion on the data base.

  6. Eleventh annual Department of Energy low-level waste management conference. Volume 3: Waste characterization, waste reduction and minimization, prototype licensing application

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1989-11-01

    Thirteen papers are presented in volume 3. The seven papers on waste characterization discuss sampling, analysis, and certification techniques for low-level radioactive wastes. Three papers discuss US DOE waste minimization policies and regulations, Y-12 Plant`s reduction of chlorinated solvents, and C-14 removal from spent resins. The last three papers discuss the licensing studies for earth-mounded concrete bunkers for LLW disposal. Papers have been processed separately for inclusion on the data base.

  7. Application of calcium chloride as an additive for secondary refrigerant in the air conditioning system type chiller to minimized energy consumption

    Science.gov (United States)

    Suwono, A.; Indartono, Y. S.; Irsyad, M.; Al-Afkar, I. C.

    2015-09-01

    One way to resolve the energy problem is to increase the efficiency of energy use. Air conditioning system is one of the equipment that needs to be considered, because it is the biggest energy user in commercial building sector. Research currently developing is the use of phase change materials (PCM) as thermal energy storage (TES) in the air conditioning system to reduce energy consumption. Salt hydrates have been great potential to be developed because they have been high latent heat and thermal conductivity. This study has used a salt hydrate from calcium chloride to be tested in air conditioning systems type chiller. Thermal characteristics were examined using temperature history (T-history) test and differential scanning calorimetry (DSC). The test results showed that the thermal characteristics of the salt hydrate has been a high latent heat and in accordance with the evaporator temperature. The use of salt hydrates in air conditioning system type chiller can reduce energy consumption by 51.5%.

  8. Natural minimal dark matter

    CERN Document Server

    Fabbrichesi, Marco

    2015-01-01

    We show how the Higgs boson mass is protected from the potentially large corrections due to the introduction of minimal dark matter if the new physics sector is made supersymmetric. The fermionic dark matter candidate (a 5-plet of $SU(2)_L$) is accompanied by a scalar state. The weak gauge sector is made supersymmetric and the Higgs boson is embedded in a supersymmetric multiplet. The remaining standard model states are non-supersymmetric. Non vanishing corrections to the Higgs boson mass only appear at three-loop level and the model is natural for dark matter masses up to 15 TeV--a value larger than the one required by the cosmological relic density. The construction presented stands as an example of a general approach to naturalness that solves the little hierarchy problem which arises when new physics is added beyond the standard model at an energy scale around 10 TeV.

  9. Increasingly minimal bias routing

    Energy Technology Data Exchange (ETDEWEB)

    Bataineh, Abdulla; Court, Thomas; Roweth, Duncan

    2017-02-21

    A system and algorithm configured to generate diversity at the traffic source so that packets are uniformly distributed over all of the available paths, but to increase the likelihood of taking a minimal path with each hop the packet takes. This is achieved by configuring routing biases so as to prefer non-minimal paths at the injection point, but increasingly prefer minimal paths as the packet proceeds, referred to herein as Increasing Minimal Bias (IMB).

  10. Logarithmic superconformal minimal models

    Science.gov (United States)

    Pearce, Paul A.; Rasmussen, Jørgen; Tartaglia, Elena

    2014-05-01

    The higher fusion level logarithmic minimal models {\\cal LM}(P,P';n) have recently been constructed as the diagonal GKO cosets {(A_1^{(1)})_k\\oplus (A_1^ {(1)})_n}/ {(A_1^{(1)})_{k+n}} where n ≥ 1 is an integer fusion level and k = nP/(P‧- P) - 2 is a fractional level. For n = 1, these are the well-studied logarithmic minimal models {\\cal LM}(P,P')\\equiv {\\cal LM}(P,P';1). For n ≥ 2, we argue that these critical theories are realized on the lattice by n × n fusion of the n = 1 models. We study the critical fused lattice models {\\cal LM}(p,p')_{n\\times n} within a lattice approach and focus our study on the n = 2 models. We call these logarithmic superconformal minimal models {\\cal LSM}(p,p')\\equiv {\\cal LM}(P,P';2) where P = |2p - p‧|, P‧ = p‧ and p, p‧ are coprime. These models share the central charges c=c^{P,P';2}=\\frac {3}{2}\\big (1-{2(P'-P)^2}/{P P'}\\big ) of the rational superconformal minimal models {\\cal SM}(P,P'). Lattice realizations of these theories are constructed by fusing 2 × 2 blocks of the elementary face operators of the n = 1 logarithmic minimal models {\\cal LM}(p,p'). Algebraically, this entails the fused planar Temperley-Lieb algebra which is a spin-1 Birman-Murakami-Wenzl tangle algebra with loop fugacity β2 = [x]3 = x2 + 1 + x-2 and twist ω = x4 where x = eiλ and λ = (p‧- p)π/p‧. The first two members of this n = 2 series are superconformal dense polymers {\\cal LSM}(2,3) with c=-\\frac {5}{2}, β2 = 0 and superconformal percolation {\\cal LSM}(3,4) with c = 0, β2 = 1. We calculate the bulk and boundary free energies analytically. By numerically studying finite-size conformal spectra on the strip with appropriate boundary conditions, we argue that, in the continuum scaling limit, these lattice models are associated with the logarithmic superconformal models {\\cal LM}(P,P';2). For system size N, we propose finitized Kac character formulae of the form q^{-{c^{P,P';2}}/{24}+\\Delta ^{P,P';2} _{r

  11. Conformational characteristics of dimeric subunits of RNA from energy minimization studies. Mixed sugar-puckered ApG, ApU, CpG, and CpU.

    Science.gov (United States)

    Thiyagarajan, P; Ponnuswamy, P K

    1981-09-01

    Following the procedure described in the preceding article, the low energy conformations located for the four dimeric subunits of RNA, ApG, ApU, CpG, and CpU are presented. The A-RNA type and Watson-Crick type helical conformations and a number of different kinds of loop promoting ones were identified as low energy in all the units. The 3E-3E and 3E-2E pucker sequences are found to be more or less equally preferred; the 2E-2E sequence is occasionally preferred, while the 2E-3E is highly prohibited in all the units. A conformation similar to the one observed in the drug-dinucleoside monophosphate complex crystals becomes a low energy case only for the CpG unit. The low energy conformations obtained for the four model units were used to assess the stability of the conformational states of the dinucleotide segments in the four crystal models of the tRNAPhe molecule. Information on the occurrence of the less preferred sugar-pucker sequences in the various loop regions in the tRNAPhe molecule has been obtained. A detailed comparison of the conformational characteristics of DNA and RNA subunits at the dimeric level is presented on the basis of the results.

  12. 2016 migratory waterbird and shorebird surveys to inform solar energy zone planning, avian impact minimization, and species conservation in the San Luis Valley, Colorado

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — In 2012, the U.S. Department of the Interior (DOI) and U.S. Department of Energy (DOE) designated approximately 6600 ha (16,308 ac) of Bureau of Land Management...

  13. 2015 migratory waterbird and shorebird surveys to inform solar energy zone planning, avian impact minimization, and species conservation in the San Luis Valley, Colorado

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — In 2012, the U.S. Department of the Interior (DOI) and U.S. Department of Energy (DOE) designated approximately 6600 ha (16,308 ac) of Bureau of Land Management...

  14. Locally minimal topological groups

    OpenAIRE

    Außenhofer, Lydia; Chasco, María Jesús; Dikranjan, Dikran; Domínguez, Xabier

    2009-01-01

    A Hausdorff topological group $(G,\\tau)$ is called locally minimal if there exists a neighborhood $U$ of 0 in $\\tau$ such that $U$ fails to be a neighborhood of zero in any Hausdorff group topology on $G$ which is strictly coarser than $\\tau.$ Examples of locally minimal groups are all subgroups of Banach-Lie groups, all locally compact groups and all minimal groups. Motivated by the fact that locally compact NSS groups are Lie groups, we study the connection between local minimality and the ...

  15. Global minimizers of coexistence for competing species

    OpenAIRE

    2010-01-01

    A class of variational models describing ecological systems of k species competing for the same resources is investigated. The occurrence of coexistence in minimal energy solutions is discussed and positive results are proven for suitably differentiated internal dynamics.

  16. Energy-saving and pollution-minimization continuous dyeing processes%印染厂连续染整节能减排工艺

    Institute of Scientific and Technical Information of China (English)

    马学亚; 冯森

    2011-01-01

    In order to save water and energy and reduce emissions, a senes of short processes are developed.Pretreatment processes include low alkali desizing and scouring and peroxide bleaching process, enzyme desizing and scouring and peroxide bleaching process, as well as peroxide desizing and scouring and peroxide bleaching process.Dyeing processes include saltfree continuous pad-steam process with reactive dyes, pad dyeing of cotton fabric with pigments, pad dyeing of polyester/cotton fabric with disperse dyes and pigmentS in one bath, as well as pad dyeing of polyester/cotton fabric in pale shade with disperse dyes.Water/oil/stain proofing and anti-static finishing in one bath is also introduced.%为了降低水耗和能耗,减少排污,开发了一系列短流程工艺,前处理包括低碱退煮氧漂、酶退煮氧漂和氧退煮氧漂工艺;染色包括活性染料无盐轧蒸工艺、纯棉涂料轧染、涤棉分散/涂料一浴轧染和浅色涤棉单分散轧染工艺;整理包括抗静电三防同浴工艺.

  17. Optimal battery charging, Part I: Minimizing time-to-charge, energy loss, and temperature rise for OCV-resistance battery model

    Science.gov (United States)

    Abdollahi, A.; Han, X.; Avvari, G. V.; Raghunathan, N.; Balasingam, B.; Pattipati, K. R.; Bar-Shalom, Y.

    2016-01-01

    In this paper we present a closed-form solution to the problem of optimally charging a Li-ion battery. A combination of three cost functions is considered as the objective function: time-to-charge (TTC), energy losses (EL), and a temperature rise index (TRI). First, we consider the cost function of the optimization problem as a weighted sum of TTC and EL. We show that the optimal charging strategy in this case is the well-known Constant Current-Constant Voltage (CC-CV) policy with the value of the current in the CC stage being a function of the ratio of weighting on TTC and EL and of the resistance of the battery. Then, we extend the cost function to a weighted sum of TTC, EL and TRI and derive an analytical solution for the problem. It is shown that the analytical solution can be approximated by a CC-CV with the value of current in the CC stage being a function of ratio of weighting on TTC and EL, resistance of the battery and the effective thermal resistance.

  18. On minimal round functions

    NARCIS (Netherlands)

    Khimshiashvili, G.; Siersma, D.

    2001-01-01

    We describe the structure of minimal round functions on closed surfaces and three-folds. The minimal possible number of critical loops is determined and typical non-equisingular round function germs are interpreted in the spirit of isolated line singularities. We also discuss a version of Lusternik-

  19. Short fasting does not protect perfused ex vivo rat liver against ischemia-reperfusion. On the importance of a minimal cell energy charge.

    Science.gov (United States)

    Papegay, Bérengère; Stadler, Michaela; Nuyens, Vincent; Kruys, Véronique; Boogaerts, Jean G; Vamecq, Joseph

    2017-03-01

    Dietary restriction or reduced food intake was supported to protect against renal and hepatic ischemic injury. In this vein, short fasting was recently shown to protect in situ rat liver against ischemia-reperfusion. Here, perfused ex vivo instead of in situ livers were exposed to ischemia-reperfusion to study the impact of disconnecting liver from extrahepatic supply in energetic substrates on the protection given by short-term fasting. Perfused ex vivo livers using short (18 h) fasted compared with fed rats were submitted to ischemia-reperfusion and studied for release of cytolysis markers in the perfusate. Energetic stores are differently available in time and cell energetic charges (ratio of adenosine triphosphate plus half of the adenosine diphosphate concentrations to the sum of adenosine triphosphate + adenosine diphosphate + adenosine monophosphate concentrations), adenosine phosphates, and glycogen, which were further measured at different time points in livers. Short fasting versus feeding failed to protect perfused ex vivo rat livers against ischemia/reperfusion, increasing the release of cytolysis markers (potassium, cytochrome c, aspartate aminotransferase, alanine aminotransferase, and lactate dehydrogenase) in the perfusate during reoxygenation phase. Toxicity of short fasting versus feeding was associated with lower glycogen and energetic charges in livers and lower lactate levels in the perfusate. High energetic charge, intracellular content in glycogen, and glycolytic activity may protect liver against ischemia/reperfusion injury. This work does not question how much the protective role previously demonstrated in the literature for dietary restriction and short fasting. In fact, it suggests that exceeding the energy charge threshold value of 0.3 might trigger the effectiveness of this protective role. Copyright © 2016 Elsevier Inc. All rights reserved.

  20. Principle of minimal work fluctuations.

    Science.gov (United States)

    Xiao, Gaoyang; Gong, Jiangbin

    2015-08-01

    Understanding and manipulating work fluctuations in microscale and nanoscale systems are of both fundamental and practical interest. For example, in considering the Jarzynski equality 〈e-βW〉=e-βΔF, a change in the fluctuations of e-βW may impact how rapidly the statistical average of e-βW converges towards the theoretical value e-βΔF, where W is the work, β is the inverse temperature, and ΔF is the free energy difference between two equilibrium states. Motivated by our previous study aiming at the suppression of work fluctuations, here we obtain a principle of minimal work fluctuations. In brief, adiabatic processes as treated in quantum and classical adiabatic theorems yield the minimal fluctuations in e-βW. In the quantum domain, if a system initially prepared at thermal equilibrium is subjected to a work protocol but isolated from a bath during the time evolution, then a quantum adiabatic process without energy level crossing (or an assisted adiabatic process reaching the same final states as in a conventional adiabatic process) yields the minimal fluctuations in e-βW, where W is the quantum work defined by two energy measurements at the beginning and at the end of the process. In the classical domain where the classical work protocol is realizable by an adiabatic process, then the classical adiabatic process also yields the minimal fluctuations in e-βW. Numerical experiments based on a Landau-Zener process confirm our theory in the quantum domain, and our theory in the classical domain explains our previous numerical findings regarding the suppression of classical work fluctuations [G. Y. Xiao and J. B. Gong, Phys. Rev. E 90, 052132 (2014)].

  1. A Minimally Symmetric Higgs Boson

    CERN Document Server

    Low, Ian

    2014-01-01

    Models addressing the naturalness of a light Higgs boson typically employ symmetries, either bosonic or fermionic, to stabilize the Higgs mass. We consider a setup with the minimal amount of symmetries: four shift symmetries acting on the four components of the Higgs doublet, subject to the constraints of linearly realized SU(2)xU(1) electroweak symmetry. Up to terms that explicitly violate the shift symmetries, the effective lagrangian can be derived, irrespective of the spontaneously broken group G in the ultraviolet, and is universal in all models where the Higgs arises as a pseudo-Nambu-Goldstone boson (PNGB). Very high energy scatterings of vector bosons could provide smoking gun signals of a minimally symmetric Higgs boson.

  2. Minimal change disease

    Science.gov (United States)

    ... get worse You develop new symptoms, including side effects from the medicines used to treat the disorder Alternative Names Minimal change nephrotic syndrome; Nil disease; Lipoid nephrosis; Idiopathic nephrotic syndrome of childhood Images ...

  3. Minimal Orderings Revisited

    Energy Technology Data Exchange (ETDEWEB)

    Peyton, B.W.

    1999-07-01

    When minimum orderings proved too difficult to deal with, Rose, Tarjan, and Leuker instead studied minimal orderings and how to compute them (Algorithmic aspects of vertex elimination on graphs, SIAM J. Comput., 5:266-283, 1976). This paper introduces an algorithm that is capable of computing much better minimal orderings much more efficiently than the algorithm in Rose et al. The new insight is a way to use certain structures and concepts from modern sparse Cholesky solvers to re-express one of the basic results in Rose et al. The new algorithm begins with any initial ordering and then refines it until a minimal ordering is obtained. it is simple to obtain high-quality low-cost minimal orderings by using fill-reducing heuristic orderings as initial orderings for the algorithm. We examine several such initial orderings in some detail.

  4. Minimal Markov Models

    CERN Document Server

    Gonzalez-Lopez, Jesus E Garcia Veronica A

    2010-01-01

    In this work we introduce a new and richer class of finite order Markov chain models and address the following model selection problem: find the Markov model with the minimal set of parameters (minimal Markov model) which is necessary to represent a source as a Markov chain of finite order. Let us call $M$ the order of the chain and $A$ the finite alphabet, to determine the minimal Markov model, we define an equivalence relation on the state space $A^{M}$, such that all the sequences of size $M$ with the same transition probabilities are put in the same category. In this way we have one set of $(|A|-1)$ transition probabilities for each category, obtaining a model with a minimal number of parameters. We show that the model can be selected consistently using the Bayesian information criterion.

  5. Ruled Laguerre minimal surfaces

    KAUST Repository

    Skopenkov, Mikhail

    2011-10-30

    A Laguerre minimal surface is an immersed surface in ℝ 3 being an extremal of the functional ∫ (H 2/K-1)dA. In the present paper, we prove that the only ruled Laguerre minimal surfaces are up to isometry the surfaces ℝ (φλ) = (Aφ, Bφ, Cφ + D cos 2φ) + λ(sin φ, cos φ, 0), where A,B,C,D ε ℝ are fixed. To achieve invariance under Laguerre transformations, we also derive all Laguerre minimal surfaces that are enveloped by a family of cones. The methodology is based on the isotropic model of Laguerre geometry. In this model a Laguerre minimal surface enveloped by a family of cones corresponds to a graph of a biharmonic function carrying a family of isotropic circles. We classify such functions by showing that the top view of the family of circles is a pencil. © 2011 Springer-Verlag.

  6. Concentrator design to minimize LCOE

    Science.gov (United States)

    McDonald, Mark; Horne, Steve; Conley, Gary

    2007-09-01

    The Levelized Cost of Energy (LCOE) takes into account more than just the cost of power output. It encompasses product longevity, performance degradation and the costs associated with delivering energy to the grid tie point. Concentrator optical design is one of the key components to minimizing the LCOE, by affecting conversion efficiency, acceptance angle and the amount of energy concentrated on the receiver. Optical systems for concentrators, even those at high concentrations ( >350X) can be designed by straightforward techniques, and will operate under most circumstances. Adding requirements for generous acceptance angles, non-destructive off-axis operation, safety and high efficiency however, complicate the design. Furthermore, the demands of high volume manufacturing, efficient logistics, minimal field commissioning time and low cost lead to quite complicated, system level design trade-offs. The technology which we will discuss features an array of reflective optics, scaled to be fabricated by techniques used in the automotive industry. The design couples a two-element imaging system to a non-imaging total internal reflection tertiary in a very compact design, with generous tolerance margins. Several optical units are mounted in a housing, which protects the optics and assists with dissipating waste heat. This paper outlines the key elements in the design of SolFocus concentrator optics, and discusses tradeoffs and experience with various design approaches.

  7. 4-[(1-Benzyl-1H-1,2,3-triazol-4-ylmethoxy]benzene-1,2-dicarbonitrile: crystal structure, Hirshfeld surface analysis and energy-minimization calculations

    Directory of Open Access Journals (Sweden)

    Norzianah Shamsudin

    2016-04-01

    Full Text Available In the solid state, the title compound, C18H13N5O, adopts a conformation whereby the phenyl ring and methoxy–benzene-1,2-dicarbonitrile residue (r.m.s. deviation of the 12 non-H atoms = 0.041 Å lie to opposite sides of the central triazolyl ring, forming dihedral angles of 79.30 (13 and 64.59 (10°, respectively; the dihedral angle between the outer rings is 14.88 (9°. This conformation is nearly 7 kcal mol−1 higher in energy than the energy-minimized structure which has a syn disposition of the outer rings, enabling intramolecular π–π interactions. In the crystal, methylene-C—H...N(triazolyl and carbonitrile-N...π(benzene interactions lead to supramolecular chains along the a axis. Supramolecular layers in the ab plane arise as the chains are connected by benzene-C—H...N(carbonitrile interactions; layers stack with no directional interactions between them. The specified intermolecular contacts along with other, weaker contributions to the supramolecular stabilization are analysed in a Hirshfeld surface analysis.

  8. Locally minimal topological groups

    CERN Document Server

    enhofer, Lydia Au\\ss; Dikranjan, Dikran; Domínguez, Xabier

    2009-01-01

    A Hausdorff topological group $(G,\\tau)$ is called locally minimal if there exists a neighborhood $U$ of 0 in $\\tau$ such that $U$ fails to be a neighborhood of zero in any Hausdorff group topology on $G$ which is strictly coarser than $\\tau.$ Examples of locally minimal groups are all subgroups of Banach-Lie groups, all locally compact groups and all minimal groups. Motivated by the fact that locally compact NSS groups are Lie groups, we study the connection between local minimality and the NSS property, establishing that under certain conditions, locally minimal NSS groups are metrizable. A symmetric subset of an abelian group containing zero is said to be a GTG set if it generates a group topology in an analogous way as convex and symmetric subsets are unit balls for pseudonorms on a vector space. We consider topological groups which have a neighborhood basis at zero consisting of GTG sets. Examples of these locally GTG groups are: locally pseudo--convex spaces, groups uniformly free from small subgroups (...

  9. Adaptive Alternating Minimization Algorithms

    CERN Document Server

    Niesen, Urs; Wornell, Gregory

    2007-01-01

    The classical alternating minimization (or projection) algorithm has been successful in the context of solving optimization problems over two variables or equivalently of finding a point in the intersection of two sets. The iterative nature and simplicity of the algorithm has led to its application to many areas such as signal processing, information theory, control, and finance. A general set of sufficient conditions for the convergence and correctness of the algorithm is quite well-known when the underlying problem parameters are fixed. In many practical situations, however, the underlying problem parameters are changing over time, and the use of an adaptive algorithm is more appropriate. In this paper, we study such an adaptive version of the alternating minimization algorithm. As a main result of this paper, we provide a general set of sufficient conditions for the convergence and correctness of the adaptive algorithm. Perhaps surprisingly, these conditions seem to be the minimal ones one would expect in ...

  10. Minimal E$_{0}$-semigroups

    CERN Document Server

    Arveson, W

    1995-01-01

    It is known that every semigroup of normal completely positive maps of a von Neumann can be ``dilated" in a particular way to an E_0-semigroup acting on a larger von Neumann algebra. The E_0-semigroup is not uniquely determined by the completely positive semigroup; however, it is unique (up to conjugacy) provided that certain conditions of {\\it minimality} are met. Minimality is a subtle property, and it is often not obvious if it is satisfied for specific examples even in the simplest case where the von Neumann algebra is \\Cal B(H). In this paper we clarify these issues by giving a new characterization of minimality in terms projective cocycles and their limits. Our results are valid for semigroups of endomorphisms acting on arbitrary von Neumann algebras with separable predual.

  11. Minimal constrained supergravity

    Directory of Open Access Journals (Sweden)

    N. Cribiori

    2017-01-01

    Full Text Available We describe minimal supergravity models where supersymmetry is non-linearly realized via constrained superfields. We show that the resulting actions differ from the so called “de Sitter” supergravities because we consider constraints eliminating directly the auxiliary fields of the gravity multiplet.

  12. Minimally invasive periodontal therapy.

    Science.gov (United States)

    Dannan, Aous

    2011-10-01

    Minimally invasive dentistry is a concept that preserves dentition and supporting structures. However, minimally invasive procedures in periodontal treatment are supposed to be limited within periodontal surgery, the aim of which is to represent alternative approaches developed to allow less extensive manipulation of surrounding tissues than conventional procedures, while accomplishing the same objectives. In this review, the concept of minimally invasive periodontal surgery (MIPS) is firstly explained. An electronic search for all studies regarding efficacy and effectiveness of MIPS between 2001 and 2009 was conducted. For this purpose, suitable key words from Medical Subject Headings on PubMed were used to extract the required studies. All studies are demonstrated and important results are concluded. Preliminary data from case cohorts and from many studies reveal that the microsurgical access flap, in terms of MIPS, has a high potential to seal the healing wound from the contaminated oral environment by achieving and maintaining primary closure. Soft tissues are mostly preserved and minimal gingival recession is observed, an important feature to meet the demands of the patient and the clinician in the esthetic zone. However, although the potential efficacy of MIPS in the treatment of deep intrabony defects has been proved, larger studies are required to confirm and extend the reported positive preliminary outcomes.

  13. Prostate resection - minimally invasive

    Science.gov (United States)

    ... invasive URL of this page: //medlineplus.gov/ency/article/007415.htm Prostate resection - minimally invasive To use ... into your bladder instead of out through the urethra ( retrograde ... on New Developments in Prostate Cancer and Prostate Diseases. Evaluation and treatment of lower ...

  14. 10 CFR 20.1406 - Minimization of contamination.

    Science.gov (United States)

    2010-01-01

    ... 10 Energy 1 2010-01-01 2010-01-01 false Minimization of contamination. 20.1406 Section 20.1406... License Termination § 20.1406 Minimization of contamination. (a) Applicants for licenses, other than early... procedures for operation will minimize, to the extent practicable, contamination of the facility and...

  15. Energy

    CERN Document Server

    Foland, Andrew Dean

    2007-01-01

    Energy is the central concept of physics. Unable to be created or destroyed but transformable from one form to another, energy ultimately determines what is and isn''t possible in our universe. This book gives readers an appreciation for the limits of energy and the quantities of energy in the world around them. This fascinating book explores the major forms of energy: kinetic, potential, electrical, chemical, thermal, and nuclear.

  16. Minimal hepatic encephalopathy.

    Science.gov (United States)

    Zamora Nava, Luis Eduardo; Torre Delgadillo, Aldo

    2011-06-01

    The term minimal hepatic encephalopathy (MHE) refers to the subtle changes in cognitive function, electrophysiological parameters, cerebral neurochemical/neurotransmitter homeostasis, cerebral blood flow, metabolism, and fluid homeostasis that can be observed in patients with cirrhosis who have no clinical evidence of hepatic encephalopathy; the prevalence is as high as 84% in patients with hepatic cirrhosis. Physician does generally not perceive cirrhosis complications, and neuropsychological tests and another especial measurement like evoked potentials and image studies like positron emission tomography can only make diagnosis. Diagnosis of minimal hepatic encephalopathy may have prognostic and therapeutic implications in cirrhotic patients. The present review pretends to explore the clinic, therapeutic, diagnosis and prognostic aspects of this complication.

  17. Minimal triangulations of simplotopes

    CERN Document Server

    Seacrest, Tyler

    2009-01-01

    We derive lower bounds for the size of simplicial covers of simplotopes, which are products of simplices. These also serve as lower bounds for triangulations of such polytopes, including triangulations with interior vertices. We establish that a minimal triangulation of a product of two simplices is given by a vertex triangulation, i.e., one without interior vertices. For products of more than two simplices, we produce bounds for products of segments and triangles. Our analysis yields linear programs that arise from considerations of covering exterior faces and exploiting the product structure of these polytopes. Aside from cubes, these are the first known lower bounds for triangulations of simplotopes with three or more factors. We also construct a minimal triangulation for the product of a triangle and a square, and compare it to our lower bound.

  18. On Minimal Constraint Networks

    CERN Document Server

    Gottlob, Georg

    2011-01-01

    In a minimal binary constraint network, every tuple of a constraint relation can be extended to a solution. It was conjectured that computing a solution to such a network is NP complete. We prove this conjecture true and show that the problem remains NP hard even in case the total domain of all values that may appear in the constraint relations is bounded by a constant.

  19. Energy

    CERN Document Server

    Robertson, William C

    2002-01-01

    Confounded by kinetic energy? Suspect that teaching about simple machines isn t really so simple? Exasperated by electricity? If you fear the study of energy is beyond you, this entertaining book will do more than introduce you to the topic. It will help you actually understand it. At the book s heart are easy-to-grasp explanations of energy basics work, kinetic energy, potential energy, and the transformation of energy and energy as it relates to simple machines, heat energy, temperature, and heat transfer. Irreverent author Bill Robertson suggests activities that bring the basic concepts of energy to life with common household objects. Each chapter ends with a summary and an applications section that uses practical examples such as roller coasters and home heating systems to explain energy transformations and convection cells. The final chapter brings together key concepts in an easy-to-grasp explanation of how electricity is generated. Energy is the second book in the Stop Faking It! series published by NS...

  20. Next-to-Minimal SOFTSUSY

    CERN Document Server

    Allanach, B C; Tunstall, Lewis C; Voigt, A; Williams, A G

    2013-01-01

    We describe an extension to the SOFTSUSY program that provides for the calculation of the sparticle spectrum in the Next-to-Minimal Supersymmetric Standard Model (NMSSM), where a chiral superfield that is a singlet of the Standard Model gauge group is added to the Minimal Supersymmetric Standard Model (MSSM) fields. Often, a $\\mathbb{Z}_{3}$ symmetry is imposed upon the model. SOFTSUSY can calculate the spectrum in this case as well as the case where general $\\mathbb{Z}_{3}$ violating (denoted as $\\,\\mathbf{\\backslash}\\mkern-11.0mu{\\mathbb{Z}}_{3}$) terms are added to the soft supersymmetry breaking terms and the superpotential. The user provides a theoretical boundary condition for the couplings and mass terms of the singlet. Radiative electroweak symmetry breaking data along with electroweak and CKM matrix data are used as weak-scale boundary conditions. The renormalisation group equations are solved numerically between the weak scale and a high energy scale using a nested iterative algorithm. This paper se...

  1. Risk minimization by experimental mechanics

    Energy Technology Data Exchange (ETDEWEB)

    1992-01-01

    Experimental mechanics has to undertake new functions to confirm theoretical perceptions and to check results of numerical analysis, because such results are dependent on the validity of assumptions and suppositions which generally are necessary to enable mathematical analysis of complex problems. Methods of experimental mechanics have become essential to design structures and products of a large variety to save raw materials and energy, to improve safety against failure and reliability of products, structures and even complex technical systems. Experimental methods are applied in system identification of complex structures. They are developed also as tools for supervising operating systems, machinery and installations as well as engineering structures, in order to get reliable informations on the life-time, to guarantee a higher degree of safety and to minimize risks. Therefore, methods of experimental mechanics are quite essential in developing strategies of riskmanagement. The contributions to this report are dealing with new theoretical perceptions, practical applications and experiences according to the objectives of the international symposium on 'Risk Minimization by Experimental Mechanics'. (orig.).

  2. Minimally Invasive Parathyroidectomy

    Directory of Open Access Journals (Sweden)

    Lee F. Starker

    2011-01-01

    Full Text Available Minimally invasive parathyroidectomy (MIP is an operative approach for the treatment of primary hyperparathyroidism (pHPT. Currently, routine use of improved preoperative localization studies, cervical block anesthesia in the conscious patient, and intraoperative parathyroid hormone analyses aid in guiding surgical therapy. MIP requires less surgical dissection causing decreased trauma to tissues, can be performed safely in the ambulatory setting, and is at least as effective as standard cervical exploration. This paper reviews advances in preoperative localization, anesthetic techniques, and intraoperative management of patients undergoing MIP for the treatment of pHPT.

  3. Minimal E6 unification

    Science.gov (United States)

    Susič, Vasja

    2016-06-01

    A realistic model in the class of renormalizable supersymmetric E6 Grand Unified Theories is constructed. Its matter sector consists of 3 × 27 representations, while the Higgs sector is 27 +27 ¯+35 1'+35 1' ¯+78 . An analytic solution for a Standard Model vacuum is found and the Yukawa sector analyzed. It is argued that if one considers the increased predictability due to only two symmetric Yukawa matrices in this model, it can be considered a minimal SUSY E6 model with this type of matter sector. This contribution is based on Ref. [1].

  4. Minimally packed phases in holography

    CERN Document Server

    Donos, Aristomenis

    2015-01-01

    We numerically construct asymptotically AdS black brane solutions of $D=4$ Einstein-Maxwell theory coupled to a pseudoscalar. The solutions are holographically dual to $d=3$ CFTs held at constant chemical potential and magnetic field that spontaneously break translation invariance leading to the spontaneous formation of abelian and momentum magnetisation currents flowing around the plaquettes of a periodic Bravais lattice. We analyse the three-dimensional moduli space of lattice solutions, which are generically oblique, and show that the free energy is minimised by the triangular lattice, associated with minimal packing of circles in the plane. The triangular structure persists at low temperatures indicating the existence of novel crystalline ground states.

  5. Non-minimally flavour violating dark matter

    CERN Document Server

    Blanke, Monika

    2015-01-01

    Flavour symmetries provide an appealing mechanism to stabilize the dark matter particle. I present a simple model of quark flavoured dark matter that goes beyond the framework of minimal flavour violation. I discuss the phenomenological implications for direct and indirect dark matter detection experiments, high energy collider searches as well as flavour violating precision data.

  6. 基于失电风险最小的机组恢复顺序优化方法%Optimization of Units”Restoration Sequence Based on Minimizing Risk of Electrical Energy Loss

    Institute of Scientific and Technical Information of China (English)

    刘艳; 张华

    2015-01-01

    Following a massive outage,it is essential for smooth network reconstruction to identify a safe and effective units”restoration sequence.Based on the definition of unit”s restoring risk and taking the duration into consideration,the concept of risk of electrical energy loss during the network reconfiguration is further proposed.Through integration of crossover particle swarm optimization and Floyd algorithm,the risk of electrical energy loss can be minimized by means of detailed simulation of network reconfiguration.As a result,the optimal units” restoration sequence with higher operational reliability as well as the best technical performance is resolved.In particular,investigation on the effect of the unit”s off-line duration on unit”s starting and reconfiguration progress is made closer to field situation by calling the embedded simulation program of thermal unit”s starting and load picking-up.The outcome of its application on the New England 10-unit 39-bus power system indicates the validity of the method proposed.%大停电发生后,寻找安全、快速而有效的机组恢复顺序是顺利重建网架的基础。文中以网络重构阶段机组投运风险的定义为基础,加入恢复时间对重构过程的影响,进一步提出失电风险的概念。以网架重构过程中的系统失电风险最小为目标,将交叉粒子群优化算法与 Floyd 算法相结合,通过对重构过程的详细模拟,优化求解综合考虑机组恢复效果及运行可靠性的最优机组恢复顺序。通过重构模拟过程对火电机组启动及升负荷仿真程序的内嵌式调用,使得针对机组停机时间对其启动过程及网架重构进程影响的研究更加贴近实际。针对新英格兰10机39节点系统的仿真结果表明了该方法的有效性。

  7. Minimal Mirror Twin Higgs

    CERN Document Server

    Barbieri, Riccardo; Harigaya, Keisuke

    2016-01-01

    In a Mirror Twin World with a maximally symmetric Higgs sector the little hierarchy of the Standard Model can be significantly mitigated, perhaps displacing the cutoff scale above the LHC reach. We show that consistency with observations requires that the Z2 parity exchanging the Standard Model with its mirror be broken in the Yukawa couplings. A minimal such effective field theory, with this sole Z2 breaking, can generate the Z2 breaking in the Higgs sector necessary for the Twin Higgs mechanism, and has constrained and correlated signals in invisible Higgs decays, direct Dark Matter Detection and Dark Radiation, all within reach of foreseen experiments. For dark matter, both mirror neutrons and a variety of self-interacting mirror atoms are considered. Neutrino mass signals and the effects of a possible additional Z2 breaking from the vacuum expectation values of B-L breaking fields are also discussed.

  8. Minimal Hepatic Encephalopathy

    Directory of Open Access Journals (Sweden)

    Laura M Stinton

    2013-01-01

    Full Text Available Minimal hepatic encephalopathy (MHE is the earliest form of hepatic encephalopathy and can affect up to 80% of cirrhotic patients. By definition, it has no obvious clinical manifestation and is characterized by neurocognitive impairment in attention, vigilance and integrative function. Although often not considered to be clinically relevant and, therefore, not diagnosed or treated, MHE has been shown to affect daily functioning, quality of life, driving and overall mortality. The diagnosis of MHE has traditionally been achieved through neuropsychological examination, psychometric tests or the newer critical flicker frequency test. A new smartphone application (EncephalApp Stroop Test may serve to function as a screening tool for patients requiring further testing. In addition to physician reporting and driving restrictions, medical treatment for MHE includes non-absorbable disaccharides (eg, lactulose, probiotics or rifaximin. Liver transplantation may not result in reversal of the cognitive deficits associated with MHE.

  9. Minimally extended SILH

    Energy Technology Data Exchange (ETDEWEB)

    Chala, Mikael [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Valencia Univ. (Spain). Dept. de Fisica Teorica y IFIC; Durieux, Gauthier; Matsedonskyi, Oleksii [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Grojean, Christophe [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Humboldt-Univ. Berlin (Germany). Inst. fuer Physik; Lima, Leonardo de [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Univ. Estadual Paulista, Sao Paulo (Brazil). Inst. de Fisica Teorica

    2017-03-15

    Higgs boson compositeness is a phenomenologically viable scenario addressing the hierarchy problem. In minimal models, the Higgs boson is the only degree of freedom of the strong sector below the strong interaction scale. We present here the simplest extension of such a framework with an additional composite spin-zero singlet. To this end, we adopt an effective field theory approach and develop a set of rules to estimate the size of the various operator coefficients, relating them to the parameters of the strong sector and its structural features. As a result, we obtain the patterns of new interactions affecting both the new singlet and the Higgs boson's physics. We identify the characteristics of the singlet field which cause its effects on Higgs physics to dominate over the ones inherited from the composite nature of the Higgs boson. Our effective field theory construction is supported by comparisons with explicit UV models.

  10. Resource Minimization Job Scheduling

    Science.gov (United States)

    Chuzhoy, Julia; Codenotti, Paolo

    Given a set J of jobs, where each job j is associated with release date r j , deadline d j and processing time p j , our goal is to schedule all jobs using the minimum possible number of machines. Scheduling a job j requires selecting an interval of length p j between its release date and deadline, and assigning it to a machine, with the restriction that each machine executes at most one job at any given time. This is one of the basic settings in the resource-minimization job scheduling, and the classical randomized rounding technique of Raghavan and Thompson provides an O(logn/loglogn)-approximation for it. This result has been recently improved to an O(sqrt{log n})-approximation, and moreover an efficient algorithm for scheduling all jobs on O((OPT)^2) machines has been shown. We build on this prior work to obtain a constant factor approximation algorithm for the problem.

  11. Energy

    Science.gov (United States)

    2003-01-01

    Canada, Britain, and Spain. We found that the energy industry is not in crisis ; however, U.S. government policies, laws, dollars, and even public...CEIMAT (Centro de Investagaciones Energeticas , Medioambeintales y Tecnologicas) Research and development Page 3 of 28ENERGY 8/10/04http://www.ndu.edu...meet an emerging national crisis (war), emergency (natural disaster), or major impact event (Y2K). Certain resources are generally critical to the

  12. Minimally invasive treatments for perforator vein insufficiency.

    Science.gov (United States)

    Kuyumcu, Gokhan; Salazar, Gloria Maria; Prabhakar, Anand M; Ganguli, Suvranu

    2016-12-01

    Incompetent superficial veins are the most common cause of lower extremity superficial venous reflux and varicose veins; however, incompetent or insufficient perforator veins are the most common cause of recurrent varicose veins after treatment, often unrecognized. Perforator vein insufficiency can result in pain, skin changes, and skin ulcers, and often merit intervention. Minimally invasive treatments have replaced traditional surgical treatments for incompetent perforator veins. Current minimally invasive treatment options include ultrasound guided sclerotherapy (USGS) and endovascular thermal ablation (EVTA) with either laser or radiofrequency energy sources. Advantages and disadvantages of each modality and knowledge on these treatments are required to adequately address perforator venous disease.

  13. Minimal Log Gravity

    CERN Document Server

    Giribet, Gaston

    2014-01-01

    Minimal Massive Gravity (MMG) is an extension of three-dimensional Topologically Massive Gravity that, when formulated about Anti-de Sitter space, accomplishes to solve the tension between bulk and boundary unitarity that other models in three dimensions suffer from. We study this theory at the chiral point, i.e. at the point of the parameter space where one of the central charges of the dual conformal field theory vanishes. We investigate the non-linear regime of the theory, meaning that we study exact solutions to the MMG field equations that are not Einstein manifolds. We exhibit a large class of solutions of this type, which behave asymptotically in different manners. In particular, we find analytic solutions that represent two-parameter deformations of extremal Banados-Teitelboim-Zanelli (BTZ) black holes. These geometries behave asymptotically as solutions of the so-called Log Gravity, and, despite the weakened falling-off close to the boundary, they have finite mass and finite angular momentum, which w...

  14. Minimal dilaton model

    Directory of Open Access Journals (Sweden)

    Oda Kin-ya

    2013-05-01

    Full Text Available Both the ATLAS and CMS experiments at the LHC have reported the observation of the particle of mass around 125 GeV which is consistent to the Standard Model (SM Higgs boson, but with an excess of events beyond the SM expectation in the diphoton decay channel at each of them. There still remains room for a logical possibility that we are not seeing the SM Higgs but something else. Here we introduce the minimal dilaton model in which the LHC signals are explained by an extra singlet scalar of the mass around 125 GeV that slightly mixes with the SM Higgs heavier than 600 GeV. When this scalar has a vacuum expectation value well beyond the electroweak scale, it can be identified as a linearly realized version of a dilaton field. Though the current experimental constraints from the Higgs search disfavors such a region, the singlet scalar model itself still provides a viable alternative to the SM Higgs in interpreting its search results.

  15. Minimal log gravity

    Science.gov (United States)

    Giribet, Gaston; Vásquez, Yerko

    2015-01-01

    Minimal massive gravity (MMG) is an extension of three-dimensional topologically massive gravity that, when formulated about anti-de Sitter space, accomplishes solving the tension between bulk and boundary unitarity that other models in three dimensions suffer from. We study this theory at the chiral point, i.e. at the point of the parameter space where one of the central charges of the dual conformal field theory vanishes. We investigate the nonlinear regime of the theory, meaning that we study exact solutions to the MMG field equations that are not Einstein manifolds. We exhibit a large class of solutions of this type, which behave asymptotically in different manners. In particular, we find analytic solutions that represent two-parameter deformations of extremal Bañados-Teitelboim-Zanelli black holes. These geometries behave asymptotically as solutions of the so-called log gravity, and, despite the weakened falling off close to the boundary, they have finite mass and finite angular momentum, which we compute. We also find time-dependent deformations of Bañados-Teitelboim-Zanelli that obey Brown-Henneaux asymptotic boundary conditions. The existence of such solutions shows that the Birkhoff theorem does not hold in MMG at the chiral point. Other peculiar features of the theory at the chiral point, such as the degeneracy it exhibits in the decoupling limit, are discussed.

  16. Minimal distances between SCFTs

    Energy Technology Data Exchange (ETDEWEB)

    Buican, Matthew [Department of Physics and Astronomy, Rutgers University,Piscataway, NJ 08854 (United States)

    2014-01-28

    We study lower bounds on the minimal distance in theory space between four-dimensional superconformal field theories (SCFTs) connected via broad classes of renormalization group (RG) flows preserving various amounts of supersymmetry (SUSY). For N=1 RG flows, the ultraviolet (UV) and infrared (IR) endpoints of the flow can be parametrically close. On the other hand, for RG flows emanating from a maximally supersymmetric SCFT, the distance to the IR theory cannot be arbitrarily small regardless of the amount of (non-trivial) SUSY preserved along the flow. The case of RG flows from N=2 UV SCFTs is more subtle. We argue that for RG flows preserving the full N=2 SUSY, there are various obstructions to finding examples with parametrically close UV and IR endpoints. Under reasonable assumptions, these obstructions include: unitarity, known bounds on the c central charge derived from associativity of the operator product expansion, and the central charge bounds of Hofman and Maldacena. On the other hand, for RG flows that break N=2→N=1, it is possible to find IR fixed points that are parametrically close to the UV ones. In this case, we argue that if the UV SCFT possesses a single stress tensor, then such RG flows excite of order all the degrees of freedom of the UV theory. Furthermore, if the UV theory has some flavor symmetry, we argue that the UV central charges should not be too large relative to certain parameters in the theory.

  17. Image denoising by a direct variational minimization

    Directory of Open Access Journals (Sweden)

    Pilipović Stevan

    2011-01-01

    Full Text Available Abstract In this article we introduce a novel method for the image de-noising which combines a mathematically well-posdenes of the variational modeling with the efficiency of a patch-based approach in the field of image processing. It based on a direct minimization of an energy functional containing a minimal surface regularizer that uses fractional gradient. The minimization is obtained on every predefined patch of the image, independently. By doing so, we avoid the use of an artificial time PDE model with its inherent problems of finding optimal stopping time, as well as the optimal time step. Moreover, we control the level of image smoothing on each patch (and thus on the whole image by adapting the Lagrange multiplier using the information on the level of discontinuities on a particular patch, which we obtain by pre-processing. In order to reduce the average number of vectors in the approximation generator and still to obtain the minimal degradation, we combine a Ritz variational method for the actual minimization on a patch, and a complementary fractional variational principle. Thus, the proposed method becomes computationally feasible and applicable for practical purposes. We confirm our claims with experimental results, by comparing the proposed method with a couple of PDE-based methods, where we get significantly better denoising results specially on the oscillatory regions.

  18. Next to new minimal standard model

    Energy Technology Data Exchange (ETDEWEB)

    Haba, Naoyuki [Graduate School of Science and Engineering, Shimane University, Matsue, Shimane 690-8504 (Japan); Department of Physics, Faculty of Science, Hokkaido University, Sapporo, Hokkaido 060-0810 (Japan); Kaneta, Kunio [Department of Physics, Faculty of Science, Hokkaido University, Sapporo, Hokkaido 060-0810 (Japan); Kavli IPMU (WPI), The University of Tokyo, Kashiwa, Chiba 277-8568 (Japan); Department of Physics, Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043 (Japan); Takahashi, Ryo [Department of Physics, Faculty of Science, Hokkaido University, Sapporo, Hokkaido 060-0810 (Japan)

    2014-06-27

    We suggest a minimal extension of the standard model, which can explain current experimental data of the dark matter, small neutrino masses and baryon asymmetry of the universe, inflation, and dark energy, and achieve gauge coupling unification. The gauge coupling unification can explain the charge quantization, and be realized by introducing six new fields. We investigate the vacuum stability, coupling perturbativity, and correct dark matter abundance in this model by use of current experimental data.

  19. On stable compact minimal submanifolds

    CERN Document Server

    Torralbo, Francisco

    2010-01-01

    Stable compact minimal submanifolds of the product of a sphere and any Riemannian manifold are classified whenever the dimension of the sphere is at least three. The complete classification of the stable compact minimal submanifolds of the product of two spheres is obtained. Also, it is proved that the only stable compact minimal surfaces of the product of a 2-sphere and any Riemann surface are the complex ones.

  20. Global Analysis of Minimal Surfaces

    CERN Document Server

    Dierkes, Ulrich; Tromba, Anthony J

    2010-01-01

    Many properties of minimal surfaces are of a global nature, and this is already true for the results treated in the first two volumes of the treatise. Part I of the present book can be viewed as an extension of these results. For instance, the first two chapters deal with existence, regularity and uniqueness theorems for minimal surfaces with partially free boundaries. Here one of the main features is the possibility of 'edge-crawling' along free parts of the boundary. The third chapter deals with a priori estimates for minimal surfaces in higher dimensions and for minimizers of singular integ

  1. Minimal surfaces for architectural constructions

    Directory of Open Access Journals (Sweden)

    Velimirović Ljubica S.

    2008-01-01

    Full Text Available Minimal surfaces are the surfaces of the smallest area spanned by a given boundary. The equivalent is the definition that it is the surface of vanishing mean curvature. Minimal surface theory is rapidly developed at recent time. Many new examples are constructed and old altered. Minimal area property makes this surface suitable for application in architecture. The main reasons for application are: weight and amount of material are reduced on minimum. Famous architects like Otto Frei created this new trend in architecture. In recent years it becomes possible to enlarge the family of minimal surfaces by constructing new surfaces.

  2. On minimal artinian modules and minimal artinian linear groups

    Directory of Open Access Journals (Sweden)

    Leonid A. Kurdachenko

    2001-01-01

    minimal artinian linear groups. The authors prove that in such classes of groups as hypercentral groups (so also, nilpotent and abelian groups and FC-groups, minimal artinian linear groups have precisely the same structure as the corresponding irreducible linear groups.

  3. Annual Waste Minimization Summary Report, Calendar Year 2008

    Energy Technology Data Exchange (ETDEWEB)

    NSTec Environmental Management

    2009-02-01

    This report summarizes the waste minimization efforts undertaken by National Security Technologies, LLC (NSTec), for the U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office (NNSA/NSO), during calendar year 2008.

  4. Minimal massive 3D gravity

    NARCIS (Netherlands)

    Bergshoeff, Eric; Hohm, Olaf; Merbis, Wout; Routh, Alasdair J.; Townsend, Paul K.

    2014-01-01

    We present an alternative to topologically massive gravity (TMG) with the same 'minimal' bulk properties; i.e. a single local degree of freedom that is realized as a massive graviton in linearization about an anti-de Sitter (AdS) vacuum. However, in contrast to TMG, the new 'minimal massive gravity'

  5. Uniqueness of PL Minimal Surfaces

    Institute of Scientific and Technical Information of China (English)

    Yi NI

    2007-01-01

    Using a standard fact in hyperbolic geometry, we give a simple proof of the uniqueness of PL minimal surfaces, thus filling in a gap in the original proof of Jaco and Rubinstein. Moreover, in order to clarify some ambiguity, we sharpen the definition of PL minimal surfaces, and prove a technical lemma on the Plateau problem in the hyperbolic space.

  6. Guidelines for mixed waste minimization

    Energy Technology Data Exchange (ETDEWEB)

    Owens, C.

    1992-02-01

    Currently, there is no commercial mixed waste disposal available in the United States. Storage and treatment for commercial mixed waste is limited. Host States and compacts region officials are encouraging their mixed waste generators to minimize their mixed wastes because of management limitations. This document provides a guide to mixed waste minimization.

  7. Influenza SIRS with Minimal Pneumonitis.

    Science.gov (United States)

    Erramilli, Shruti; Mannam, Praveen; Manthous, Constantine A

    2016-01-01

    Although systemic inflammatory response syndrome (SIRS) is a known complication of severe influenza pneumonia, it has been reported very rarely in patients with minimal parenchymal lung disease. We here report a case of severe SIRS, anasarca, and marked vascular phenomena with minimal or no pneumonitis. This case highlights that viruses, including influenza, may cause vascular dysregulation causing SIRS, even without substantial visceral organ involvement.

  8. Minimal changes in health status questionnaires: distinction between minimally detectable change and minimally important change

    Directory of Open Access Journals (Sweden)

    Knol Dirk L

    2006-08-01

    Full Text Available Abstract Changes in scores on health status questionnaires are difficult to interpret. Several methods to determine minimally important changes (MICs have been proposed which can broadly be divided in distribution-based and anchor-based methods. Comparisons of these methods have led to insight into essential differences between these approaches. Some authors have tried to come to a uniform measure for the MIC, such as 0.5 standard deviation and the value of one standard error of measurement (SEM. Others have emphasized the diversity of MIC values, depending on the type of anchor, the definition of minimal importance on the anchor, and characteristics of the disease under study. A closer look makes clear that some distribution-based methods have been merely focused on minimally detectable changes. For assessing minimally important changes, anchor-based methods are preferred, as they include a definition of what is minimally important. Acknowledging the distinction between minimally detectable and minimally important changes is useful, not only to avoid confusion among MIC methods, but also to gain information on two important benchmarks on the scale of a health status measurement instrument. Appreciating the distinction, it becomes possible to judge whether the minimally detectable change of a measurement instrument is sufficiently small to detect minimally important changes.

  9. Minimal Webs in Riemannian Manifolds

    DEFF Research Database (Denmark)

    Markvorsen, Steen

    2008-01-01

    are of instrumental importance for the applications. We apply these properties to show that minimal webs in ambient Riemannian spaces share several analytic and geometric properties with their smooth (minimal submanifold) counterparts in such spaces. In particular we use appropriate versions of the divergence......)$ into Riemannian manifolds $(N^{n}, h)$. Such immersions we call {\\em{minimal webs}}. They admit a natural 'geometric' extension of the intrinsic combinatorial discrete Laplacian. The geometric Laplacian on minimal webs enjoys standard properties such as the maximum principle and the divergence theorems, which...... theorems together with the comparison techniques for distance functions in Riemannian geometry and obtain bounds for the first Dirichlet eigenvalues, the exit times and the capacities as well as isoperimetric type inequalities for so-called extrinsic $R-$webs of minimal webs in ambient Riemannian manifolds...

  10. Waste minimization handbook, Volume 1

    Energy Technology Data Exchange (ETDEWEB)

    Boing, L.E.; Coffey, M.J.

    1995-12-01

    This technical guide presents various methods used by industry to minimize low-level radioactive waste (LLW) generated during decommissioning and decontamination (D and D) activities. Such activities generate significant amounts of LLW during their operations. Waste minimization refers to any measure, procedure, or technique that reduces the amount of waste generated during a specific operation or project. Preventive waste minimization techniques implemented when a project is initiated can significantly reduce waste. Techniques implemented during decontamination activities reduce the cost of decommissioning. The application of waste minimization techniques is not limited to D and D activities; it is also useful during any phase of a facility`s life cycle. This compendium will be supplemented with a second volume of abstracts of hundreds of papers related to minimizing low-level nuclear waste. This second volume is expected to be released in late 1996.

  11. Subspace Correction Methods for Total Variation and $\\ell_1$-Minimization

    KAUST Repository

    Fornasier, Massimo

    2009-01-01

    This paper is concerned with the numerical minimization of energy functionals in Hilbert spaces involving convex constraints coinciding with a seminorm for a subspace. The optimization is realized by alternating minimizations of the functional on a sequence of orthogonal subspaces. On each subspace an iterative proximity-map algorithm is implemented via oblique thresholding, which is the main new tool introduced in this work. We provide convergence conditions for the algorithm in order to compute minimizers of the target energy. Analogous results are derived for a parallel variant of the algorithm. Applications are presented in domain decomposition methods for degenerate elliptic PDEs arising in total variation minimization and in accelerated sparse recovery algorithms based on 1-minimization. We include numerical examples which show e.cient solutions to classical problems in signal and image processing. © 2009 Society for Industrial and Applied Physics.

  12. National Institutes of Health: Mixed waste minimization and treatment

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-08-01

    The Appalachian States Low-Level Radioactive Waste Commission requested the US Department of Energy`s National Low-Level Waste Management Program (NLLWMP) to assist the biomedical community in becoming more knowledgeable about its mixed waste streams, to help minimize the mixed waste stream generated by the biomedical community, and to identify applicable treatment technologies for these mixed waste streams. As the first step in the waste minimization process, liquid low-level radioactive mixed waste (LLMW) streams generated at the National Institutes of Health (NIH) were characterized and combined into similar process categories. This report identifies possible waste minimization and treatment approaches for the LLMW generated by the biomedical community identified in DOE/LLW-208. In development of the report, on site meetings were conducted with NIH personnel responsible for generating each category of waste identified as lacking disposal options. Based on the meetings and general waste minimization guidelines, potential waste minimization options were identified.

  13. Superspace geometry and the minimal, non minimal, and new minimal supergravity multiplets

    Energy Technology Data Exchange (ETDEWEB)

    Girardi, G.; Grimm, R.; Mueller, M.; Wess, J.

    1984-11-01

    We analyse superspace constraints in a systematic way and define a set of natural constraints. We give a complete solution of the Bianchi identities subject to these constraints and obtain a reducible, but not fully reducible multiplet. By additional constraints it can be reduced to either the minimal nonminimal or new minimal multiplet. We discuss the superspace actions for the various multiplets.

  14. Locally minimal topological groups 1

    OpenAIRE

    Chasco, María Jesús; Dikranjan, Dikran N.; Außenhofer, Lydia; Domínguez, Xabier

    2015-01-01

    The aim of this paper is to go deeper into the study of local minimality and its connection to some naturally related properties. A Hausdorff topological group ▫$(G,tau)$▫ is called locally minimal if there exists a neighborhood ▫$U$▫ of 0 in ▫$tau$▫ such that ▫$U$▫ fails to be a neighborhood of zero in any Hausdorff group topology on ▫$G$▫ which is strictly coarser than ▫$tau$▫. Examples of locally minimal groups are all subgroups of Banach-Lie groups, all locally compact groups and all mini...

  15. Minimal flows and their extensions

    CERN Document Server

    Auslander, J

    1988-01-01

    This monograph presents developments in the abstract theory of topological dynamics, concentrating on the internal structure of minimal flows (actions of groups on compact Hausdorff spaces for which every orbit is dense) and their homomorphisms (continuous equivariant maps). Various classes of minimal flows (equicontinuous, distal, point distal) are intensively studied, and a general structure theorem is obtained. Another theme is the ``universal'' approach - entire classes of minimal flows are studied, rather than flows in isolation. This leads to the consideration of disjointness of flows, w

  16. Renewable energy.

    Science.gov (United States)

    Destouni, Georgia; Frank, Harry

    2010-01-01

    The Energy Committee of the Royal Swedish Academy of Sciences has in a series of projects gathered information and knowledge on renewable energy from various sources, both within and outside the academic world. In this article, we synthesize and summarize some of the main points on renewable energy from the various Energy Committee projects and the Committee's Energy 2050 symposium, regarding energy from water and wind, bioenergy, and solar energy. We further summarize the Energy Committee's scenario estimates of future renewable energy contributions to the global energy system, and other presentations given at the Energy 2050 symposium. In general, international coordination and investment in energy research and development is crucial to enable future reliance on renewable energy sources with minimal fossil fuel use.

  17. Sludge minimization technologies - an overview

    Energy Technology Data Exchange (ETDEWEB)

    Oedegaard, Hallvard

    2003-07-01

    The management of wastewater sludge from wastewater treatment plants represents one of the major challenges in wastewater treatment today. The cost of the sludge treatment amounts to more that the cost of the liquid in many cases. Therefore the focus on and interest in sludge minimization is steadily increasing. In the paper an overview is given for sludge minimization (sludge mass reduction) options. It is demonstrated that sludge minimization may be a result of reduced production of sludge and/or disintegration processes that may take place both in the wastewater treatment stage and in the sludge stage. Various sludge disintegration technologies for sludge minimization are discussed, including mechanical methods (focusing on stirred ball-mill, high-pressure homogenizer, ultrasonic disintegrator), chemical methods (focusing on the use of ozone), physical methods (focusing on thermal and thermal/chemical hydrolysis) and biological methods (focusing on enzymatic processes). (author)

  18. Minimally invasive surgery. Future developments.

    OpenAIRE

    1994-01-01

    The rapid development of minimally invasive surgery means that there will be fundamental changes in interventional treatment. Technological advances will allow new minimally invasive procedures to be developed. Application of robotics will allow some procedures to be done automatically, and coupling of slave robotic instruments with virtual reality images will allow surgeons to perform operations by remote control. Miniature motors and instruments designed by microengineering could be introdu...

  19. Cost minimization and asset pricing

    OpenAIRE

    Robert G. Chambers; John Quiggin

    2005-01-01

    A cost-based approach to asset-pricing equilibrium relationships is developed. A cost function induces a stochastic discount factor (pricing kernel) that is a function of random output, prices, and capital stockt. By eliminating opportunities for arbitrage between financial markets and the production technology, firms minimize the current cost of future consumption. The first-order conditions for this cost minimization problem generate the stochastic discount factor. The cost-based approach i...

  20. Influenza SIRS with minimal pneumonitis

    Directory of Open Access Journals (Sweden)

    Shruti Erramilli

    2016-08-01

    Full Text Available While systemic inflammatory response syndrome (SIRS, is a known complication of severe influenza pneumonia, it has been reported very rarely in patients with minimal parenchymal lung disease. We here report a case of severe SIRS, anasarca and marked vascular phenomena with minimal or no pneumonitis. This case highlights that viruses, including influenza, may cause vascular dysregulation causing SIRS, even without substantial visceral organ involvement.

  1. Minimal relativistic three-particle equations

    Energy Technology Data Exchange (ETDEWEB)

    Lindesay, J.

    1981-07-01

    A minimal self-consistent set of covariant and unitary three-particle equations is presented. Numerical results are obtained for three-particle bound states, elastic scattering and rearrangement of bound pairs with a third particle, and amplitudes for breakup into states of three free particles. The mathematical form of the three-particle bound state equations is explored; constraints are set upon the range of eigenvalues and number of eigenstates of these one parameter equations. The behavior of the number of eigenstates as the two-body binding energy decreases to zero in a covariant context generalizes results previously obtained non-relativistically by V. Efimov.

  2. Functional minimization problems in image processing

    Science.gov (United States)

    Kim, Yunho; Vese, Luminita A.

    2008-02-01

    In this work we wish to recover an unknown image from a blurry version. We solve this inverse problem by energy minimization and regularization. We seek a solution of the form u + v, where u is a function of bounded variation (cartoon component), while v is an oscillatory component (texture), modeled by a Sobolev function with negative degree of differentiability. Experimental results show that this cartoon + texture model better recovers textured details in natural images, by comparison with the more standard models where the unknown is restricted only to the space of functions of bounded variation.

  3. Minimizing water consumption when producing hydropower

    Science.gov (United States)

    Leon, A. S.

    2015-12-01

    In 2007, hydropower accounted for only 16% of the world electricity production, with other renewable sources totaling 3%. Thus, it is not surprising that when alternatives are evaluated for new energy developments, there is strong impulse for fossil fuel or nuclear energy as opposed to renewable sources. However, as hydropower schemes are often part of a multipurpose water resources development project, they can often help to finance other components of the project. In addition, hydropower systems and their associated dams and reservoirs provide human well-being benefits, such as flood control and irrigation, and societal benefits such as increased recreational activities and improved navigation. Furthermore, hydropower due to its associated reservoir storage, can provide flexibility and reliability for energy production in integrated energy systems. The storage capability of hydropower systems act as a regulating mechanism by which other intermittent and variable renewable energy sources (wind, wave, solar) can play a larger role in providing electricity of commercial quality. Minimizing water consumption for producing hydropower is critical given that overuse of water for energy production may result in a shortage of water for other purposes such as irrigation, navigation or fish passage. This paper presents a dimensional analysis for finding optimal flow discharge and optimal penstock diameter when designing impulse and reaction water turbines for hydropower systems. The objective of this analysis is to provide general insights for minimizing water consumption when producing hydropower. This analysis is based on the geometric and hydraulic characteristics of the penstock, the total hydraulic head and the desired power production. As part of this analysis, various dimensionless relationships between power production, flow discharge and head losses were derived. These relationships were used to withdraw general insights on determining optimal flow discharge and

  4. Partnership in developing waste minimization training

    Energy Technology Data Exchange (ETDEWEB)

    Snyder, R.L. Jr. [BDM/Federal, Germantown, MD (United States); Dutro, C. [Reynolds Electrical and Engineering Co., Inc., Las Vegas, NV (United States); Colarusso, A. [USDOE Nevada Operations Office, Las Vegas, NV (United States)

    1994-12-31

    At the Department of Energy Nevada Operations Office (DOE/NV), a joint Task Force of key organizations, i.e. DOE, operations and support contractors, and laboratories, was established in 1991 to implement solid and hazardous waste minimization efforts across the site. In early 1992 it became clear that the most effective waste minimization would be achieved when pollution prevention and waste minimization opportunities were identified and endorsed throughout the workforce. It was decided that, with 6,000 Nevada Test Site DOE and contractor employees having diverse jobs, basic and personalized information should be presented to the workers through course handouts, performance-based training (PBT) materials, and videotapes. The Task Force developed such materials, supplemented with company-specific information which was then used for instruction by the Task Force designated program trainers or disseminated to supervisors for use in monthly briefings. This paper identifies the approach taken by the Task Force to meet these needs of the Nevada Site. It details program elements developed by the Task Force and the steps taken to implement the elements. Additionally, some program cost savings and the lessons learned are identified.

  5. Minimally Invasive Video-Assisted versus Minimally Invasive Nonendoscopic Thyroidectomy

    Directory of Open Access Journals (Sweden)

    Zdeněk Fík

    2014-01-01

    Full Text Available Minimally invasive video-assisted thyroidectomy (MIVAT and minimally invasive nonendoscopic thyroidectomy (MINET represent well accepted and reproducible techniques developed with the main goal to improve cosmetic outcome, accelerate healing, and increase patient’s comfort following thyroid surgery. Between 2007 and 2011, a prospective nonrandomized study of patients undergoing minimally invasive thyroid surgery was performed to compare advantages and disadvantages of the two different techniques. There were no significant differences in the length of incision to perform surgical procedures. Mean duration of hemithyroidectomy was comparable in both groups, but it was more time consuming to perform total thyroidectomy by MIVAT. There were more patients undergoing MIVAT procedures without active drainage in the postoperative course and we also could see a trend for less pain in the same group. This was paralleled by statistically significant decreased administration of both opiates and nonopiate analgesics. We encountered two cases of recurrent laryngeal nerve palsies in the MIVAT group only. MIVAT and MINET represent safe and feasible alternative to conventional thyroid surgery in selected cases and this prospective study has shown minimal differences between these two techniques.

  6. Minimizing Costs Can Be Costly

    Directory of Open Access Journals (Sweden)

    Rasmus Rasmussen

    2010-01-01

    Full Text Available A quite common practice, even in academic literature, is to simplify a decision problem and model it as a cost-minimizing problem. In fact, some type of models has been standardized to minimization problems, like Quadratic Assignment Problems (QAPs, where a maximization formulation would be treated as a “generalized” QAP and not solvable by many of the specially designed softwares for QAP. Ignoring revenues when modeling a decision problem works only if costs can be separated from the decisions influencing revenues. More often than we think this is not the case, and minimizing costs will not lead to maximized profit. This will be demonstrated using spreadsheets to solve a small example. The example is also used to demonstrate other pitfalls in network models: the inability to generally balance the problem or allocate costs in advance, and the tendency to anticipate a specific type of solution and thereby make constraints too limiting when formulating the problem.

  7. Minimal Marking: A Success Story

    Directory of Open Access Journals (Sweden)

    Anne McNeilly

    2014-11-01

    Full Text Available The minimal-marking project conducted in Ryerson’s School of Journalism throughout 2012 and early 2013 resulted in significantly higher grammar scores in two first-year classes of minimally marked university students when compared to two traditionally marked classes. The “minimal-marking” concept (Haswell, 1983, which requires dramatically more student engagement, resulted in more successful learning outcomes for surface-level knowledge acquisition than the more traditional approach of “teacher-corrects-all.” Results suggest it would be effective, not just for grammar, punctuation, and word usage, the objective here, but for any material that requires rote-memory learning, such as the Associated Press or Canadian Press style rules used by news publications across North America.

  8. Constrained minimization of smooth functions using a genetic algorithm

    Science.gov (United States)

    Moerder, Daniel D.; Pamadi, Bandu N.

    1994-01-01

    The use of genetic algorithms for minimization of differentiable functions that are subject to differentiable constraints is considered. A technique is demonstrated for converting the solution of the necessary conditions for a constrained minimum into an unconstrained function minimization. This technique is extended as a global constrained optimization algorithm. The theory is applied to calculating minimum-fuel ascent control settings for an energy state model of an aerospace plane.

  9. Naturalness of electroweak physics within minimal supergravity

    CERN Document Server

    Cassel, S

    2011-01-01

    Low energy supersymmetry is motivated by its use as a solution to the hierarchy problem of the electroweak scale. Having motivated this model with naturalness arguments, it is then necessary to check whether the experimentally allowed parameter space permits realisations of the model with low fine tuning. The scope of this thesis is a study of naturalness of the electroweak physics in the minimal supergravity model. The latest experimental constraints are applied, and the fine tuning is quantitatively evaluated for a scan across the parameter space. The fine tuning of the electroweak scale is evaluated at 2-loop order, and the fine tuning of the neutralino dark matter thermal relic energy density is also determined. The natural regions of the parameter space are identified and the associated phenomenology relevant for detection discussed. Naturalness limits are also found for the parameter space and spectrum. The minimum fine tuning found is 1 part in 9 when dark matter constraints are neglected, and 1 part i...

  10. Utilization of biocatalysts in cellulose waste minimization

    Energy Technology Data Exchange (ETDEWEB)

    Woodward, J.; Evans, B.R.

    1996-09-01

    Cellulose, a polymer of glucose, is the principal component of biomass and, therefore, a major source of waste that is either buried or burned. Examples of biomass waste include agricultural crop residues, forestry products, and municipal wastes. Recycling of this waste is important for energy conservation as well as waste minimization and there is some probability that in the future biomass could become a major energy source and replace fossil fuels that are currently used for fuels and chemicals production. It has been estimated that in the United States, between 100-450 million dry tons of agricultural waste are produced annually, approximately 6 million dry tons of animal waste, and of the 190 million tons of municipal solid waste (MSW) generated annually, approximately two-thirds is cellulosic in nature and over one-third is paper waste. Interestingly, more than 70% of MSW is landfilled or burned, however landfill space is becoming increasingly scarce. On a smaller scale, important cellulosic products such as cellulose acetate also present waste problems; an estimated 43 thousand tons of cellulose ester waste are generated annually in the United States. Biocatalysts could be used in cellulose waste minimization and this chapter describes their characteristics and potential in bioconversion and bioremediation processes.

  11. Minimal Flavor Constraints for Technicolor

    DEFF Research Database (Denmark)

    Sakuma, Hidenori; Sannino, Francesco

    2010-01-01

    We analyze the constraints on the the vacuum polarization of the standard model gauge bosons from a minimal set of flavor observables valid for a general class of models of dynamical electroweak symmetry breaking. We will show that the constraints have a strong impact on the self-coupling and mas...

  12. Dubin's Minimal Linkage Construct Revisited.

    Science.gov (United States)

    Rogers, Donald P.

    This paper contains a theoretical analysis and empirical study that support the major premise of Robert Dubin's minimal-linkage construct-that restricting communication links increases organizational stability. The theoretical analysis shows that fewer communication links are associated with less uncertainty, more redundancy, and greater…

  13. Minimal Surfaces for Hitchin Representations

    DEFF Research Database (Denmark)

    Li, Qiongling; Dai, Song

    2016-01-01

    Given a reductive representation $\\rho: \\pi_1(S)\\rightarrow G$, there exists a $\\rho$-equivariant harmonic map $f$ from the universal cover of a fixed Riemann surface $\\Sigma$ to the symmetric space $G/K$ associated to $G$. If the Hopf differential of $f$ vanishes, the harmonic map is then minimal...

  14. Acquiring minimally invasive surgical skills

    NARCIS (Netherlands)

    Hiemstra, Ellen

    2012-01-01

    Many topics in surgical skills education have been implemented without a solid scientific basis. For that reason we have tried to find this scientific basis. We have focused on training and evaluation of minimally invasive surgical skills in a training setting and in practice in the operating room.

  15. What is minimally invasive dentistry?

    Science.gov (United States)

    Ericson, Dan

    2004-01-01

    Minimally Invasive Dentistry is the application of "a systematic respect for the original tissue." This implies that the dental profession recognizes that an artifact is of less biological value than the original healthy tissue. Minimally invasive dentistry is a concept that can embrace all aspects of the profession. The common delineator is tissue preservation, preferably by preventing disease from occurring and intercepting its progress, but also removing and replacing with as little tissue loss as possible. It does not suggest that we make small fillings to restore incipient lesions or surgically remove impacted third molars without symptoms as routine procedures. The introduction of predictable adhesive technologies has led to a giant leap in interest in minimally invasive dentistry. The concept bridges the traditional gap between prevention and surgical procedures, which is just what dentistry needs today. The evidence-base for survival of restorations clearly indicates that restoring teeth is a temporary palliative measure that is doomed to fail if the disease that caused the condition is not addressed properly. Today, the means, motives and opportunities for minimally invasive dentistry are at hand, but incentives are definitely lacking. Patients and third parties seem to be convinced that the only things that count are replacements. Namely, they are prepared to pay for a filling but not for a procedure that can help avoid having one.

  16. On Minimal Norms on Mn

    Directory of Open Access Journals (Sweden)

    Madjid Mirzavaziri

    2007-01-01

    norms ‖⋅‖1 and ‖⋅‖2 on ℂn such that N(A=max{‖Ax‖2:‖x‖1=1, x∈ℂn} for all A∈ℳn. This may be regarded as an extension of a known result on characterization of minimal algebra norms.

  17. Implications of minimally invasive therapy

    NARCIS (Netherlands)

    Banta, H.D.; Schersten, T.; Jonsson, E.

    1993-01-01

    The field of minimally invasive therapy (MIT) raises many important issues for the future of health care. It seems inevitable that MIT will replace much conventional surgery. This trend is good for society and good for patients. The health care system, however, may find the change disruptive. The

  18. The implementation of the target program for electric motors: the evolution of the energy efficiency minimal indexes; A implementacao do programa de metas de motores eletricos: a evolucao dos indices minimos de eficiencia energetica

    Energy Technology Data Exchange (ETDEWEB)

    Pinheiro, Michel Goncalves; Soares, George Alves; Pedroso, Alquindar [ELETROBRAS, Rio de Janeiro, RJ (Brazil); Rocha, Leonardo; Leme, Alexandre Paes [Instituto Nacional de Metrologia, Normalizacao e Qualidade Industrial - INMETRO, Rio de Janeiro, RJ (Brazil); Rodrigues, Fernando; Furtado, Heloisa [Centro de Pesquisas de Energia Eletrica (CEPEL), Rio de Janeiro, RJ (Brazil); Leonelli, Paulo Augusto; Tarso, Paulo de [Ministerio das Minas e Energia, Brasilia, DF (Brazil)

    2006-07-01

    Three-phase induction motors were the first products to be ever regulated for minimum performance standards because they account for a significant consumption of energy in addition to having the database that has been derived from labelling since 1992. As part of the regulation it was expected that the Target Program would indicate the minimum performance standards of motors. In 2005 it was issued and the minimum standards equaled those of high performance. The minimum levels of energy efficiency of the Target Program are similar to the ones in effect in Europe and the USA. Some of the supporting actions done by institutions of the Technical Committee of Motors are, among others, consolidating importation procedures, studying the steel market of motors, setting inspecting programs and integrating with PROCEL Industry. The government's role is not restricted to the issuing of the Target Program, but is also related to supporting actions and following-up after its implementation so as to accelerate changes in the market. (author)

  19. Harm minimization among teenage drinkers

    DEFF Research Database (Denmark)

    Jørgensen, Morten Hulvej; Curtis, Tine; Christensen, Pia Haudrup

    2007-01-01

    AIM: To examine strategies of harm minimization employed by teenage drinkers. DESIGN, SETTING AND PARTICIPANTS: Two periods of ethnographic fieldwork were conducted in a rural Danish community of approximately 2000 inhabitants. The fieldwork included 50 days of participant observation among 13......-16-year-olds (n = 93) as well as 26 semistructured interviews with small self-selected friendship groups of 15-16-year-olds (n = 32). FINDINGS: The teenagers participating in the present study were more concerned about social than health risks. The informants monitored their own level of intoxication....... In regulating the social context of drinking they relied on their personal experiences more than on formalized knowledge about alcohol and harm, which they had learned from prevention campaigns and educational programmes. CONCLUSIONS: In this study we found that teenagers may help each other to minimize alcohol...

  20. On the Hopcroft's minimization algorithm

    CERN Document Server

    Paun, Andrei

    2007-01-01

    We show that the absolute worst case time complexity for Hopcroft's minimization algorithm applied to unary languages is reached only for de Bruijn words. A previous paper by Berstel and Carton gave the example of de Bruijn words as a language that requires O(n log n) steps by carefully choosing the splitting sets and processing these sets in a FIFO mode. We refine the previous result by showing that the Berstel/Carton example is actually the absolute worst case time complexity in the case of unary languages. We also show that a LIFO implementation will not achieve the same worst time complexity for the case of unary languages. Lastly, we show that the same result is valid also for the cover automata and a modification of the Hopcroft's algorithm, modification used in minimization of cover automata.

  1. Consistency of trace norm minimization

    CERN Document Server

    Bach, Francis

    2007-01-01

    Regularization by the sum of singular values, also referred to as the trace norm, is a popular technique for estimating low rank rectangular matrices. In this paper, we extend some of the consistency results of the Lasso to provide necessary and sufficient conditions for rank consistency of trace norm minimization with the square loss. We also provide an adaptive version that is rank consistent even when the necessary condition for the non adaptive version is not fulfilled.

  2. Risk minimization and portfolio diversification

    OpenAIRE

    Farzad Pourbabaee; Minsuk Kwak; Traian A. Pirvu

    2014-01-01

    We consider the problem of minimizing capital at risk in the Black-Scholes setting. The portfolio problem is studied given the possibility that a correlation constraint between the portfolio and a financial index is imposed. The optimal portfolio is obtained in closed form. The effects of the correlation constraint are explored; it turns out that this portfolio constraint leads to a more diversified portfolio.

  3. Outcomes After Minimally Invasive Esophagectomy

    Science.gov (United States)

    Luketich, James D.; Pennathur, Arjun; Awais, Omar; Levy, Ryan M.; Keeley, Samuel; Shende, Manisha; Christie, Neil A.; Weksler, Benny; Landreneau, Rodney J.; Abbas, Ghulam; Schuchert, Matthew J.; Nason, Katie S.

    2014-01-01

    Background Esophagectomy is a complex operation and is associated with significant morbidity and mortality. In an attempt to lower morbidity, we have adopted a minimally invasive approach to esophagectomy. Objectives Our primary objective was to evaluate the outcomes of minimally invasive esophagectomy (MIE) in a large group of patients. Our secondary objective was to compare the modified McKeown minimally invasive approach (videothoracoscopic surgery, laparoscopy, neck anastomosis [MIE-neck]) with our current approach, a modified Ivor Lewis approach (laparoscopy, videothoracoscopic surgery, chest anastomosis [MIE-chest]). Methods We reviewed 1033 consecutive patients undergoing MIE. Elective operation was performed on 1011 patients; 22 patients with nonelective operations were excluded. Patients were stratified by surgical approach and perioperative outcomes analyzed. The primary endpoint studied was 30-day mortality. Results The MIE-neck was performed in 481 (48%) and MIE-Ivor Lewis in 530 (52%). Patients undergoing MIE-Ivor Lewis were operated in the current era. The median number of lymph nodes resected was 21. The operative mortality was 1.68%. Median length of stay (8 days) and ICU stay (2 days) were similar between the 2 approaches. Mortality rate was 0.9%, and recurrent nerve injury was less frequent in the Ivor Lewis MIE group (P < 0.001). Conclusions MIE in our center resulted in acceptable lymph node resection, postoperative outcomes, and low mortality using either an MIE-neck or an MIE-chest approach. The MIE Ivor Lewis approach was associated with reduced recurrent laryngeal nerve injury and mortality of 0.9% and is now our preferred approach. Minimally invasive esophagectomy can be performed safely, with good results in an experienced center. PMID:22668811

  4. Minimal Length, Measurability and Gravity

    Directory of Open Access Journals (Sweden)

    Alexander Shalyt-Margolin

    2016-03-01

    Full Text Available The present work is a continuation of the previous papers written by the author on the subject. In terms of the measurability (or measurable quantities notion introduced in a minimal length theory, first the consideration is given to a quantum theory in the momentum representation. The same terms are used to consider the Markov gravity model that here illustrates the general approach to studies of gravity in terms of measurable quantities.

  5. Optimizing Processes to Minimize Risk

    Science.gov (United States)

    Loyd, David

    2017-01-01

    NASA, like the other hazardous industries, has suffered very catastrophic losses. Human error will likely never be completely eliminated as a factor in our failures. When you can't eliminate risk, focus on mitigating the worst consequences and recovering operations. Bolstering processes to emphasize the role of integration and problem solving is key to success. Building an effective Safety Culture bolsters skill-based performance that minimizes risk and encourages successful engagement.

  6. BDD Minimization for Approximate Computing

    OpenAIRE

    Soeken, Mathias; Grosse, Daniel; Chandrasekharan, Arun; Drechsler, Rolf

    2016-01-01

    We present Approximate BDD Minimization (ABM) as a problem that has application in approximate computing. Given a BDD representation of a multi-output Boolean function, ABM asks whether there exists another function that has a smaller BDD representation but meets a threshold w.r.t. an error metric. We present operators to derive approximated functions and present algorithms to exactly compute the error metrics directly on the BDD representation. An experimental evaluation demonstrates the app...

  7. Torsional Rigidity of Minimal Submanifolds

    DEFF Research Database (Denmark)

    Markvorsen, Steen; Palmer, Vicente

    2006-01-01

    We prove explicit upper bounds for the torsional rigidity of extrinsic domains of minimal submanifolds $P^m$ in ambient Riemannian manifolds $N^n$ with a pole $p$. The upper bounds are given in terms of the torsional rigidities of corresponding Schwarz symmetrizations of the domains in warped...... for the torsional rigidity are actually attained and give conditions under which the geometric average of the stochastic mean exit time for Brownian motion at infinity is finite....

  8. Reservoir Operation to Minimize Sedimentation

    Directory of Open Access Journals (Sweden)

    Dyah Ari Wulandari

    2013-10-01

    Full Text Available The Wonogiri Reservoir capacity decreases rapidly, caused by serious sedimentation problems. In 2007, JICA was proposed a sediment storage reservoir with a new spillway for the purpose of sediment flushing / sluicing from The Keduang River. Due to the change of reservoir storage and change of reservoir system, it requires a sustainable reservoir operation technique. This technique is aimed to minimize the deviation between the input and output of sediments. The main objective of this study is to explore the optimal Wonogiri reservoir operation by minimizing the sediment trap. The CSUDP incremental dynamic programming procedure is used for the model optimization.  This new operating rules will also simulate a five years operation period, to show the effect of the implemented techniques. The result of the study are the newly developed reservoir operation system has many advantages when compared to the actual operation system and the disadvantage of this developed system is that the use is mainly designed for a wet hydrologic year, since its performance for the water supply is lower than the actual reservoir operations.Doi: 10.12777/ijse.6.1.16-23 [How to cite this article:  Wulandari, D.A., Legono, D., and Darsono, S., 2014. Reservoir Operation to Minimize Sedimentation. International Journal of Science and Engineering, 5(2,61-65. Doi: 10.12777/ijse.6.1.16-23] Normal 0 false false false EN-US X-NONE X-NONE

  9. Minimally invasive paediatric cardiac surgery.

    Science.gov (United States)

    Bacha, Emile; Kalfa, David

    2014-01-01

    The concept of minimally invasive surgery for congenital heart disease in paediatric patients is broad, and has the aim of reducing the trauma of the operation at each stage of management. Firstly, in the operating room using minimally invasive incisions, video-assisted thoracoscopic and robotically assisted surgery, hybrid procedures, image-guided intracardiac surgery, and minimally invasive cardiopulmonary bypass strategies. Secondly, in the intensive-care unit with neuroprotection and 'fast-tracking' strategies that involve early extubation, early hospital discharge, and less exposure to transfused blood products. Thirdly, during postoperative mid-term and long-term follow-up by providing the children and their families with adequate support after hospital discharge. Improvement of these strategies relies on the development of new devices, real-time multimodality imaging, aids to instrument navigation, miniaturized and specialized instrumentation, robotic technology, and computer-assisted modelling of flow dynamics and tissue mechanics. In addition, dedicated multidisciplinary co-ordinated teams involving congenital cardiac surgeons, perfusionists, intensivists, anaesthesiologists, cardiologists, nurses, psychologists, and counsellors are needed before, during, and after surgery to go beyond apparent technological and medical limitations with the goal to 'treat more while hurting less'.

  10. Energies; Energies

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2003-07-01

    In the framework of the National Debate on the energies in a context of a sustainable development some associations for the environment organized a debate on the nuclear interest facing the renewable energies. The first part presents the nuclear energy as a possible solution to fight against the greenhouse effect and the associated problem of the wastes management. The second part gives information on the solar energy and the possibilities of heat and electric power production. A presentation of the FEE (French wind power association) on the situation and the development of the wind power in France, is also provided. (A.L.B.)

  11. Minimally invasive surgery for atrial fibrillation.

    Science.gov (United States)

    Zembala, Michael O; Suwalski, Piotr

    2013-11-01

    Atrial fibrillation (AF) remains the most common cardiac arrhythmia, affecting nearly 2% of the general population worldwide. Minimally invasive surgical ablation remains one of the most dynamically evolving fields of modern cardiac surgery. While there are more than a dozen issues driving this development, two seem to play the most important role: first, there is lack of evidence supporting percutaneous catheter based approach to treat patients with persistent and long-standing persistent AF. Paucity of this data offers surgical community unparalleled opportunity to challenge guidelines and change indications for surgical intervention. Large, multicenter prospective clinical studies are therefore of utmost importance, as well as honest, clear data reporting. Second, a collaborative methodology started a long-awaited debate on a Heart Team approach to AF, similar to the debate on coronary artery disease and transcatheter valves. Appropriate patient selection and tailored treatment options will most certainly result in better outcomes and patient satisfaction, coupled with appropriate use of always-limited institutional resources. The aim of this review, unlike other reviews of minimally invasive surgical ablation, is to present medical professionals with two distinctly different, approaches. The first one is purely surgical, Standalone surgical isolation of the pulmonary veins using bipolar energy source with concomitant amputation of the left atrial appendage-a method of choice in one of the most important clinical trials on AF-The Atrial Fibrillation Catheter Ablation Versus Surgical Ablation Treatment (FAST) Trial. The second one represents the most complex approach to this problem: a multidisciplinary, combined effort of a cardiac surgeon and electrophysiologist. The Convergent Procedure, which includes both endocardial and epicardial unipolar ablation bonds together minimally invasive endoscopic surgery with electroanatomical mapping, to deliver best of the

  12. Performance potential of mechanical ventilation systems with minimized pressure loss

    DEFF Research Database (Denmark)

    Terkildsen, Søren; Svendsen, Svend

    2013-01-01

    ventilation systems with minimal pressure loss and minimal energy use. This can provide comfort ventilation and avoid overheating through increased ventilation and night cooling. Based on this concept, a test system was designed for a fictive office building and its performance was documented using building...... simulations that quantify fan power consumption, heating demand and indoor environmental conditions. The system was designed with minimal pressure loss in the duct system and heat exchanger. Also, it uses state-of-the-art components such as electrostatic precipitators, diffuse ceiling inlets and demand......-control ventilation with static pressure set-point reset. All the equipment has been designed to minimize pressure losses and thereby the fan power needed to operate the system. The total pressure loss is 30-75 Pa depending on the operating conditions. The annual average specific fan power is 330 J/m3 of airflow rate...

  13. Minimal lepton flavor violating realizations of minimal seesaw models

    CERN Document Server

    Sierra, Diego Aristizabal; Kamenik, Jernej F

    2012-01-01

    We study the implications of the global U(1)R symmetry present in minimal lepton flavor violating implementations of the seesaw mechanism for neutrino masses. In the context of minimal type I seesaw scenarios with a slightly broken U(1)R, we show that, depending on the R-charge assignments, two classes of generic models can be identified. Models where the right-handed neutrino masses and the lepton number breaking scale are decoupled, and models where the parameters that slightly break the U(1)R induce a suppression in the light neutrino mass matrix. We show that within the first class of models, contributions of right-handed neutrinos to charged lepton flavor violating processes are severely suppressed. Within the second class of models we study the charged lepton flavor violating phenomenology in detail, focusing on mu to e gamma, mu to 3e and mu to e conversion in nuclei. We show that sizable contributions to these processes are naturally obtained for right-handed neutrino masses at the TeV scale. We then ...

  14. Minimal families of curves on surfaces

    KAUST Repository

    Lubbes, Niels

    2014-11-01

    A minimal family of curves on an embedded surface is defined as a 1-dimensional family of rational curves of minimal degree, which cover the surface. We classify such minimal families using constructive methods. This allows us to compute the minimal families of a given surface.The classification of minimal families of curves can be reduced to the classification of minimal families which cover weak Del Pezzo surfaces. We classify the minimal families of weak Del Pezzo surfaces and present a table with the number of minimal families of each weak Del Pezzo surface up to Weyl equivalence.As an application of this classification we generalize some results of Schicho. We classify algebraic surfaces that carry a family of conics. We determine the minimal lexicographic degree for the parametrization of a surface that carries at least 2 minimal families. © 2014 Elsevier B.V.

  15. Minimal surfaces bounded by elastic lines

    CERN Document Server

    Giomi, L

    2011-01-01

    The classical Plateau's problem consists of finding the surface of least area that spans a given rigid boundary curve. A physical realization of the problem is obtained by dipping a stiff wire frame of some given shape in soapy water and then removing it. But what happens if a soap film spans a loop of inextensible but flexible wire? We consider this simple query that couples the Plateau's problem to Euler's Elastica: a special class of curves of given length that minimize their total squared curvature energy. The natural marriage of two of the oldest geometrical problems linking physics and mathematics leads to a quest for the shape of a minimal surface bounded by an elastic line: the Euler-Plateau problem. We use a combination of simple physical experiments with soap films that span soft filaments, scaling concepts, exact and asymptotic analysis combined with numerical simulations to explore some of the richness of the shapes that result. Our study also raises a number of interesting questions of intrinsic ...

  16. Minimal flavor violation and anomalous top decays

    Science.gov (United States)

    Faller, Sven; Mannel, Thomas; Gadatsch, Stefan

    2013-08-01

    Top-quark physics at the LHC may open a window to physics beyond the Standard Model and even lead us to an understanding of the phenomenon of “flavor.” However, current flavor data is a strong hint that no “new physics” with a generic flavor structure can be expected at the TeV scale. In turn, if there is “new physics” at the TeV scale, it must be “minimally flavor violating.” This has become a widely accepted assumption for “new physics” models. In this paper we propose a model-independent scheme to test minimal flavor violation for the anomalous charged Wtq, q∈{d,s,b} and flavor-changing Vtq, q∈{u,c} and V∈{Z,γ,g} couplings within an effective field theory framework, i.e., in a model-independent way. We perform a spurion analysis of our effective field theory approach and calculate the decay rates for the anomalous top-quark decays in terms of the effective couplings for different helicities by using a two-Higgs doublet model of type II, under the assumption that the top-quark is produced at a high-energy collision and decays as a quasi-free particle.

  17. Numerical study of liquid crystal elastomers by a mixed finite element method

    KAUST Repository

    LUO, C.

    2011-08-22

    Liquid crystal elastomers present features not found in ordinary elastic materials, such as semi-soft elasticity and the related stripe domain phenomenon. In this paper, the two-dimensional Bladon-Terentjev-Warner model and the one-constant Oseen-Frank energy expression are combined to study the liquid crystal elastomer. We also impose two material constraints, the incompressibility of the elastomer and the unit director norm of the liquid crystal. We prove existence of minimiser of the energy for the proposed model. Next we formulate the discrete model, and also prove that it possesses a minimiser of the energy. The inf-sup values of the discrete linearised system are then related to the smallest singular values of certain matrices. Next the existence and uniqueness of the Lagrange multipliers associated with the two material constraints are proved under the assumption that the inf-sup conditions hold. Finally numerical simulations of the clamped-pulling experiment are presented for elastomer samples with aspect ratio 1 or 3. The semi-soft elasticity is successfully recovered in both cases. The stripe domain phenomenon, however, is not observed, which might be due to the relative coarse mesh employed in the numerical experiment. Possible improvements are discussed that might lead to the recovery of the stripe domain phenomenon. © Copyright Cambridge University Press 2011.

  18. Minimally invasive PCNL-MIP.

    Science.gov (United States)

    Zanetti, Stefano Paolo; Boeri, Luca; Gallioli, Andrea; Talso, Michele; Montanari, Emanuele

    2017-01-01

    Miniaturized percutaneous nephrolithotomy (mini-PCNL) has increased in popularity in recent years and is now widely used to overcome the therapeutic gap between conventional PCNL and less-invasive procedures such as shock wave lithotripsy (SWL) or flexible ureterorenoscopy (URS) for the treatment of renal stones. However, despite its minimally invasive nature, the superiority in terms of safety, as well as the similar efficacy of mini-PCNL compared to conventional procedures, is still under debate. The aim of this chapter is to present one of the most recent advancements in terms of mini-PCNL: the Karl Storz "minimally invasive PCNL" (MIP). A literature search for original and review articles either published or e-published up to December 2016 was performed using Google and the PubMed database. Keywords included: minimally invasive PCNL; MIP. The retrieved articles were gathered and examined. The complete MIP set is composed of different sized rigid metallic fiber-optic nephroscopes and different sized metallic operating sheaths, according to which the MIP is categorized into extra-small (XS), small (S), medium (M) and large (L). Dilation can be performed either in one-step or with a progressive technique, as needed. The reusable devices of the MIP and vacuum cleaner efect make PCNL with this set a cheap procedure. The possibility to shift from a small to a larger instrument within the same set (Matrioska technique) makes MIP a very versatile technique suitable for the treatment of almost any stone. Studies in the literature have shown that MIP is equally effective, with comparable rates of post-operative complications, as conventional PCNL, independently from stone size. MIP does not represent a new technique, but rather a combination of the last ten years of PCNL improvements in a single system that can transversally cover all available techniques in the panorama of percutaneous stone treatment.

  19. Minimal dispersion refractive index profiles.

    Science.gov (United States)

    Feit, M D

    1979-09-01

    The analogy between optics and quantum mechanics is exploited by considering a 2-D quantum system whose Schroedinger equation is closely related to the wave equation for light propagation in an optical fiber. From this viewpoint, Marcatili's condition for minimal-dispersion-refractive-index profiles, and the Olshansky- Keck formula for rms pulse spreading in an alpha-profile fiber may be derived without recourse to the WKB approximation. Besides affording physical insight into these results, the present approach points out a possible limitation in their application to real fibers.

  20. Minimal sets of Reidemeister moves

    CERN Document Server

    Polyak, Michael

    2009-01-01

    It is well known that any two diagrams representing the same oriented link are related by a finite sequence of Reidemeister moves O1, O2 and O3. Depending on orientations of fragments involved in the moves, one may distinguish 4 different versions of each of the O1 and O2 moves, and 8 versions of the O3 move. We introduce a minimal generating set of oriented Reidemeister moves, which includes two moves of types O1 and O2, and only one move of type O3. We then consider other sets of moves and show that only few of them generate all Reidemeister moves.

  1. About the ZOOM minimization package

    Energy Technology Data Exchange (ETDEWEB)

    Fischler, M.; Sachs, D.; /Fermilab

    2004-11-01

    A new object-oriented Minimization package is available for distribution in the same manner as CLHEP. This package, designed for use in HEP applications, has all the capabilities of Minuit, but is a re-write from scratch, adhering to modern C++ design principles. A primary goal of this package is extensibility in several directions, so that its capabilities can be kept fresh with as little maintenance effort as possible. This package is distinguished by the priority that was assigned to C++ design issues, and the focus on producing an extensible system that will resist becoming obsolete.

  2. Prepulse minimization in KALI-5000

    Science.gov (United States)

    Kumar, D. Durga Praveen; Mitra, S.; Senthil, K.; Sharma, Vishnu K.; Singh, S. K.; Roy, A.; Sharma, Archana; Nagesh, K. V.; Chakravarthy, D. P.

    2009-07-01

    A pulse power system (1 MV, 50 kA, and 100 ns) based on Marx generator and Blumlein pulse forming line has been built for generating high power microwaves. The Blumlein configuration poses a prepulse problem and hence the diode gap had to be increased to match the diode impedance to the Blumlein impedance during the main pulse. A simple method to eliminate prepulse voltage using a vacuum sparkgap and a resistor is given. Another fundamental approach of increasing the inductance of Marx generator to minimize the prepulse voltage is also presented. Experimental results for both of these configurations are given.

  3. Risk minimization through portfolio replication

    Science.gov (United States)

    Ciliberti, S.; Mã©Zard, M.

    2007-05-01

    We use a replica approach to deal with portfolio optimization problems. A given risk measure is minimized using empirical estimates of asset values correlations. We study the phase transition which happens when the time series is too short with respect to the size of the portfolio. We also study the noise sensitivity of portfolio allocation when this transition is approached. We consider explicitely the cases where the absolute deviation and the conditional value-at-risk are chosen as a risk measure. We show how the replica method can study a wide range of risk measures, and deal with various types of time series correlations, including realistic ones with volatility clustering.

  4. Minimal heating and cooling in a modern rose greenhouse

    NARCIS (Netherlands)

    Beveren, van P.J.M.; Bontsema, J.; Straten, van G.; Henten, van E.

    2015-01-01

    In a modern greenhouse there are a number of alternative systems that can be deployed to control the climate, and the choice what to use and when is not easy for the grower. A novel management system is proposed, consisting of an energy input minimizing module, and a module to realise the determined

  5. Nonhomogeneous Variational Problems and Quasi-Minimizers on Metric Spaces

    CERN Document Server

    Gong, Jasun; Parviainen, Mikko

    2010-01-01

    We show that quasi-minimizers of non-homogeneous energy functionals on metric measure spaces are locally H\\"older continuous and satisfy the Harnack inequality. We assume that the spaces are doubling and support a Poincar\\'e inequality. The proof is based on the De Giorgi method, combined with the "expansion of positivity" technique.

  6. Noise Tolerance under Risk Minimization

    CERN Document Server

    Manwani, Naresh

    2011-01-01

    In this paper we explore the problem of noise tolerant learning of classifiers. We formulate the problem as follows. We assume that there is an ${\\bf unobservable}$ training set which is noise-free. The actual training set given to the learning algorithm is obtained from this ideal data set by corrupting the class label of each example where the probability that the class label on an example is corrupted is a function of the feature vector of the example. This would account for almost all kinds of noisy data one may encounter in practice. We say that a learning method is noise tolerant if the classifiers learnt with the ideal noise-free data and with noisy data have the same classification accuracy on the noise-free data. In this paper we analyze the noise tolerant properties of risk minimization, which is a generic method for learning classifiers. We consider different loss functions such as 0-1 loss, hinge loss, exponential loss, squared error loss etc. We show that the risk minimization under 0-1 loss func...

  7. Laparoscopic colonic resection in inflammatory bowel disease: minimal surgery, minimal access and minimal hospital stay.

    LENUS (Irish Health Repository)

    Boyle, E

    2008-11-01

    Laparoscopic surgery for inflammatory bowel disease (IBD) is technically demanding but can offer improved short-term outcomes. The introduction of minimally invasive surgery (MIS) as the default operative approach for IBD, however, may have inherent learning curve-associated disadvantages. We hypothesise that the establishment of MIS as the standard operative approach does not increase patient morbidity as assessed in the initial period of its introduction into a specialised unit, and that it confers earlier postoperative gastrointestinal recovery and reduced hospitalisation compared with conventional open resection.

  8. Rituximab in Minimal Change Disease

    Directory of Open Access Journals (Sweden)

    Nima Madanchi

    2017-03-01

    Full Text Available Treatment with rituximab, a monoclonal antibody against the B-lymphocyte surface protein CD20, leads to the depletion of B cells. Recently, rituximab was reported to effectively prevent relapses of glucocorticoid-dependent or frequently relapsing minimal change disease (MCD. MCD is thought to be T-cell mediated; how rituximab controls MCD is not understood. In this review, we summarize key clinical studies demonstrating the efficacy of rituximab in idiopathic nephrotic syndrome, mainly MCD. We then discuss immunological features of this disease and potential mechanisms of action of rituximab in its treatment based on what is known about the therapeutic action of rituximab in other immune-mediated disorders. We believe that studies aimed at understanding the mechanisms of action of rituximab in MCD will provide a novel approach to resolve the elusive immune pathophysiology of MCD.

  9. A minimally invasive smile enhancement.

    Science.gov (United States)

    Peck, Fred H

    2014-01-01

    Minimally invasive dentistry refers to a wide variety of dental treatments. On the restorative aspect of dental procedures, direct resin bonding can be a very conservative treatment option for the patient. When tooth structure does not need to be removed, the patient benefits. Proper treatment planning is essential to determine how conservative the restorative treatment will be. This article describes the diagnosis, treatment options, and procedural techniques in the restoration of 4 maxillary anterior teeth with direct composite resin. The procedural steps are reviewed with regard to placing the composite and the variety of colors needed to ensure a natural result. Finishing and polishing of the composite are critical to ending with a natural looking dentition that the patient will be pleased with for many years.

  10. [MINIMALLY INVASIVE AORTIC VALVE REPLACEMENT].

    Science.gov (United States)

    Tabata, Minoru

    2016-03-01

    Minimally invasive aortic valve replacement (MIAVR) is defined as aortic valve replacement avoiding full sternotomy. Common approaches include a partial sternotomy right thoracotomy, and a parasternal approach. MIAVR has been shown to have advantages over conventional AVR such as shorter length of stay and smaller amount of blood transfusion and better cosmesis. However, it is also known to have disadvantages such as longer cardiopulmonary bypass and aortic cross-clamp times and potential complications related to peripheral cannulation. Appropriate patient selection is very important. Since the procedure is more complex than conventional AVR, more intensive teamwork in the operating room is essential. Additionally, a team approach during postoperative management is critical to maximize the benefits of MIAVR.

  11. Minimization over randomly selected lines

    Directory of Open Access Journals (Sweden)

    Ismet Sahin

    2013-07-01

    Full Text Available This paper presents a population-based evolutionary optimization method for minimizing a given cost function. The mutation operator of this method selects randomly oriented lines in the cost function domain, constructs quadratic functions interpolating the cost function at three different points over each line, and uses extrema of the quadratics as mutated points. The crossover operator modifies each mutated point based on components of two points in population, instead of one point as is usually performed in other evolutionary algorithms. The stopping criterion of this method depends on the number of almost degenerate quadratics. We demonstrate that the proposed method with these mutation and crossover operations achieves faster and more robust convergence than the well-known Differential Evolution and Particle Swarm algorithms.

  12. Minimally invasive aortic valve replacement

    DEFF Research Database (Denmark)

    Foghsgaard, Signe; Schmidt, Thomas Andersen; Kjaergard, Henrik K

    2009-01-01

    In this descriptive prospective study, we evaluate the outcomes of surgery in 98 patients who were scheduled to undergo minimally invasive aortic valve replacement. These patients were compared with a group of 50 patients who underwent scheduled aortic valve replacement through a full sternotomy....... The 30-day mortality rate for the 98 patients was zero, although 14 of the 98 mini-sternotomies had to be converted to complete sternotomies intraoperatively due to technical problems. Such conversion doubled the operative time over that of the planned full sternotomies. In the group of patients whose...... is an excellent operation in selected patients, but its true advantages over conventional aortic valve replacement (other than a smaller scar) await evaluation by means of randomized clinical trial. The "extended mini-aortic valve replacement" operation, on the other hand, is a risky procedure that should...

  13. Purge water minimization at LEHR

    Energy Technology Data Exchange (ETDEWEB)

    Schalla, R.

    1996-11-01

    The field demonstration described in this report is being conducted as part of the Environmental Restoration Program at the Laboratory for Energy-Related Health Research (LEHR). The Environmental Restoration Program is one of several U.S. Department of Energy (DOE) waste cleanup projects designed to support by the actual use of emerging environmental management and restoration technologies. As part of an ongoing technical support mission to achieve excellence and efficiency in environmental restoration activities at LEHR, DOE requested Pacific Northwest National Laboratory`s (PNNL`s) guidance to identify the most efficient way of reducing purge water extracted by sampling pumps while still obtaining representative samples from LEHR monitoring wells.

  14. A minimal four-family supergravity model

    CERN Document Server

    Gunion, J F; Pois, H; McKay, Douglas W

    1996-01-01

    We investigate the phenomenology of minimal four-family MSSM supergravity theories containing an additional generation of heavy fermions along with their superpartners. We demand: gauge coupling constant unification at high energy scales; perturbative values for all Yukawa couplings for energy scales \\leq \\mgut; radiative electroweak symmetry breaking via renormalization group evolution; and a neutral LSP. The perturbative constraints imply a light fourth-family quark and lepton spectrum, and \\tanb\\lsim 3. The lightest CP-even Higgs mass is increased. Fourth-family Yukawa coupling contributions to the evolution of scalar masses lead to unexpected mass hierarchies; \\eg\\ the \\staupone is generally the lightest slepton and the lightest squark is the \\wt\\bpr_1. A significant lower bound is placed on the gluino mass by the requirement that the \\staupone not be the LSP. Sleptons of the first two families are much more massive compared to the LSP and other neutralinos and charginos than in the three-family models, a...

  15. Landscaping for energy efficiency

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-04-01

    This publication by the National Renewable Energy Laboratory addresses the use of landscaping for energy efficiency. The topics of the publication include minimizing energy expenses; landscaping for a cleaner environment; climate, site, and design considerations; planning landscape; and selecting and planting trees and shrubs. A source list for more information on landscaping for energy efficiency and a reading list are included.

  16. Minimizing energy consumption for wireless computers in Moby Dick

    NARCIS (Netherlands)

    Havinga, Paul J.M.; Smit, Gerard J.M.

    1997-01-01

    The Moby Dick project is a joint European project to develop and define the architecture of a new generation of mobile hand-held computers, called Pocket Companions. The Pocket Companion is a hand-held device that is resource-poor, i.e. small amount of memory, limited battery life, low processing po

  17. Topologically stratified energy minimizers in a product Abelian field theory

    Science.gov (United States)

    Han, Xiaosen; Yang, Yisong

    2015-09-01

    We study a recently developed product Abelian gauge field theory by Tong and Wong hosting magnetic impurities. We first obtain a necessary and sufficient condition for the existence of a unique solution realizing such impurities in the form of multiple vortices. We next reformulate the theory into an extended model that allows the coexistence of vortices and anti-vortices. The two Abelian gauge fields in the model induce two species of magnetic vortex-lines resulting from Ns vortices and Ps anti-vortices (s = 1, 2) realized as the zeros and poles of two complex-valued Higgs fields, respectively. An existence theorem is established for the governing equations over a compact Riemann surface S which states that a solution with prescribed N1, N2 vortices and P1, P2 anti-vortices of two designated species exists if and only if the inequalities

  18. Minimizing energy consumption for wireless computers in Moby Dick

    NARCIS (Netherlands)

    Havinga, Paul J.M.; Smit, Gerardus Johannes Maria

    1997-01-01

    The Moby Dick project is a joint European project to develop and define the architecture of a new generation of mobile hand-held computers, called Pocket Companions. The Pocket Companion is a hand-held device that is resource-poor, i.e. small amount of memory, limited battery life, low processing

  19. The optimum grain size for minimizing energy losses in iron

    Energy Technology Data Exchange (ETDEWEB)

    Campos, M.F. de [Escola de Engenharia Industrial Metalurgica de Volta Redonda/Universidade Federal Fluminense Av. dos Trabalhadores 420, Vila Santa Cecilia, 27255-125, Volta Redonda, RJ (Brazil)]. E-mail: mcampos@metal.eeimvr.uff.br; Teixeira, J.C. [Instituto de Pesquisas Tecnologicas do Estado de Sao Paulo, Av. Prof. Almeida Prado 532, 05508-901, Sao Paulo, SP (Brazil); Landgraf, F.J.G. [Instituto de Pesquisas Tecnologicas do Estado de Sao Paulo, Av. Prof. Almeida Prado 532, 05508-901, Sao Paulo, SP (Brazil)]. E-mail: landgraf@ipt.br

    2006-06-15

    A model able to predict the optimum grain size for textured electrical steels used in motors or transformers is presented. The model is based on the Pry and Bean model for the anomalous losses. The validity of the model is restricted to the frequency range of 1-1000 Hz. The model predicts that the optimum grain size decreases as: resistivity decreases or frequency increases or thickness of steel sheet increases. The predictions of the model are compared with experimental results.

  20. Analysis of NIF experiments with the minimal energy implosion model

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, B., E-mail: bcheng@lanl.gov; Kwan, T. J. T.; Wang, Y. M.; Merrill, F. E.; Batha, S. H. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Cerjan, C. J. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States)

    2015-08-15

    We apply a recently developed analytical model of implosion and thermonuclear burn to fusion capsule experiments performed at the National Ignition Facility that used low-foot and high-foot laser pulse formats. Our theoretical predictions are consistent with the experimental data. Our studies, together with neutron image analysis, reveal that the adiabats of the cold fuel in both low-foot and high-foot experiments are similar. That is, the cold deuterium-tritium shells in those experiments are all in a high adiabat state at the time of peak implosion velocity. The major difference between low-foot and high-foot capsule experiments is the growth of the shock-induced instabilities developed at the material interfaces which lead to fuel mixing with ablator material. Furthermore, we have compared the NIF capsules performance with the ignition criteria and analyzed the alpha particle heating in the NIF experiments. Our analysis shows that alpha heating was appreciable only in the high-foot experiments.

  1. National Ignition Facility pollution prevention and waste minimization plan

    Energy Technology Data Exchange (ETDEWEB)

    Cantwell, B.; Celeste, J.

    1998-09-01

    This document is the Lawrence Livermore National Laboratory (LLNL) National Ignition Facility (NIF) Pollution Prevention and Waste Minimization Plan. It will not only function as the planning document for anticipating, minimizing, and mitigating NIF waste generation, but it is also a Department of Energy (DOE) milestone document specified in the facility's Mitigation Action Plan (MAP). As such, it is one of the ''living'' reference documents that will guide NIF operations through all phases of the project. This document will be updated periodically to reflect development of the NIF, from construction through lifetime operations.

  2. Mini-Med School Planning Guide

    Science.gov (United States)

    National Institutes of Health, Office of Science Education, 2008

    2008-01-01

    Mini-Med Schools are public education programs now offered by more than 70 medical schools, universities, research institutions, and hospitals across the nation. There are even Mini-Med Schools in Ireland, Malta, and Canada! The program is typically a lecture series that meets once a week and provides "mini-med students" information on some of the…

  3. Robotic-assisted minimally invasive liver resection

    Directory of Open Access Journals (Sweden)

    Yao-Ming Wu

    2014-04-01

    Conclusion: Robotic assistance increased the percentage of minimally invasive liver resections and the percentage of major minimally invasive liver resections with comparable perioperative results. Robotic-assisted minimally invasive liver resection is feasible, but its role needs more accumulated experience to clarify.

  4. Compact static stars in minimal dilatonic gravity

    Science.gov (United States)

    Fiziev, Plamen P.

    2017-09-01

    In the version1 of this paper we presented for the first time the basic equations and relations for relativistic static spherically symmetric stars (SSSS) in the model of minimal dilatonic gravity (MDG). This model is locally equivalent to the f(R) theory of gravity and gives an alternative description of the effects of dark matter and dark energy using the Brans-Dicke dilaton Φ. To outline the basic properties of the MDG model of SSSS and to compare them with general relativistic results, in this paper we use the relativistic equation of state (EOS) of neutron matter as an ideal Fermi neutron gas at zero temperature. We overcome the well-known difficulties of the physics of SSSS in the f(R) theories of gravity2,3 applying novel highly nontrivial nonlinear boundary conditions, which depend on the global properties of the solution and on the EOS. We also introduce two pairs of new notions: cosmological-energy-pressure densities and dilaton-energy-pressure densities, as well as two new EOSs for them: cosmological EOS (CEOS) and dilaton EOS (DEOS). Special attention is paid to the dilatonic sphere (in brief — disphere) of SSSS, introduced in this paper for the first time. Using several realistic EOS for neutron star (NS): SLy, BSk19, BSk20 and BSk21, and current observational two-solar-masses-limit, we derive an estimate for scalar-field-mass mΦ ˜ 10‑13eV/c2 ÷ 4 × 10‑11eV/c2. Thus, the present version of the paper reflects some of the recent developments of the topic.

  5. Medical waste: a minimal hazard.

    Science.gov (United States)

    Keene, J H

    1991-11-01

    Medical waste is a subset of municipal waste, and regulated medical waste comprises less than 1% of the total municipal waste volume in the United States. As part of the overall waste stream, medical waste does contribute in a relative way to the aesthetic damage of the environment. Likewise, some small portion of the total release of hazardous chemicals and radioactive materials is derived from medical wastes. These comments can be made about any generated waste, regulated or unregulated. Healthcare professionals, including infection control personnel, microbiologists, public health officials, and others, have unsuccessfully argued that there is no evidence that past methods of treatment and disposal of regulated medical waste constitute any public health hazard. Historically, discovery of environmental contamination by toxic chemical disposal has followed assurances that the material was being disposed of in a safe manner. Therefore, a cynical public and its elected officials have demanded proof that the treatment and disposal of medical waste (i.e., infectious waste) do not constitute a public health hazard. Existent studies on municipal waste provide that proof. In order to argue that the results of these municipal waste studies are demonstrative of the minimal potential infectious environmental impact and lack of public health hazard associated with medical waste, we must accept the following: that the pathogens are the same whether they come from the hospital or the community, and that the municipal waste studied contained waste materials we now define as regulated medical waste.(ABSTRACT TRUNCATED AT 250 WORDS)

  6. Robotic assisted minimally invasive surgery

    Directory of Open Access Journals (Sweden)

    Palep Jaydeep

    2009-01-01

    Full Text Available The term "robot" was coined by the Czech playright Karel Capek in 1921 in his play Rossom′s Universal Robots. The word "robot" is from the check word robota which means forced labor.The era of robots in surgery commenced in 1994 when the first AESOP (voice controlled camera holder prototype robot was used clinically in 1993 and then marketed as the first surgical robot ever in 1994 by the US FDA. Since then many robot prototypes like the Endoassist (Armstrong Healthcare Ltd., High Wycombe, Buck, UK, FIPS endoarm (Karlsruhe Research Center, Karlsruhe, Germany have been developed to add to the functions of the robot and try and increase its utility. Integrated Surgical Systems (now Intuitive Surgery, Inc. redesigned the SRI Green Telepresence Surgery system and created the daVinci Surgical System ® classified as a master-slave surgical system. It uses true 3-D visualization and EndoWrist ® . It was approved by FDA in July 2000 for general laparoscopic surgery, in November 2002 for mitral valve repair surgery. The da Vinci robot is currently being used in various fields such as urology, general surgery, gynecology, cardio-thoracic, pediatric and ENT surgery. It provides several advantages to conventional laparoscopy such as 3D vision, motion scaling, intuitive movements, visual immersion and tremor filtration. The advent of robotics has increased the use of minimally invasive surgery among laparoscopically naοve surgeons and expanded the repertoire of experienced surgeons to include more advanced and complex reconstructions.

  7. Against Explanatory Minimalism in Psychiatry.

    Science.gov (United States)

    Thornton, Tim

    2015-01-01

    The idea that psychiatry contains, in principle, a series of levels of explanation has been criticized not only as empirically false but also, by Campbell, as unintelligible because it presupposes a discredited pre-Humean view of causation. Campbell's criticism is based on an interventionist-inspired denial that mechanisms and rational connections underpin physical and mental causation, respectively, and hence underpin levels of explanation. These claims echo some superficially similar remarks in Wittgenstein's Zettel. But attention to the context of Wittgenstein's remarks suggests a reason to reject explanatory minimalism in psychiatry and reinstate a Wittgensteinian notion of levels of explanation. Only in a context broader than the one provided by interventionism is that the ascription of propositional attitudes, even in the puzzling case of delusions, justified. Such a view, informed by Wittgenstein, can reconcile the idea that the ascription mental phenomena presupposes a particular level of explanation with the rejection of an a priori claim about its connection to a neurological level of explanation.

  8. Minimal hepatic encephalopathy: A review.

    Science.gov (United States)

    Nardone, Raffaele; Taylor, Alexandra C; Höller, Yvonne; Brigo, Francesco; Lochner, Piergiorgio; Trinka, Eugen

    2016-10-01

    Minimal hepatic encephalopathy (MHE) is the earliest form of hepatic encephalopathy and can affect up to 80% of patients with liver cirrhosis. By definition, MHE is characterized by cognitive function impairment in the domains of attention, vigilance and integrative function, but obvious clinical manifestation are lacking. MHE has been shown to affect daily functioning, quality of life, driving and overall mortality. The diagnosis can be achieved through neuropsychological testing, recently developed computerized psychometric tests, such as the critical flicker frequency and the inhibitory control tests, as well as neurophysiological procedures. Event related potentials can reveal subtle changes in patients with normal neuropsychological performances. Spectral analysis of electroencephalography (EEG) and quantitative analysis of sleep EEG provide early markers of cerebral dysfunction in cirrhotic patients with MHE. Neuroimaging, in particular MRI, also increasingly reveals diffuse abnormalities in intrinsic brain activity and altered organization of functional connectivity networks. Medical treatment for MHE to date has been focused on reducing serum ammonia levels and includes non-absorbable disaccharides, probiotics or rifaximin. Liver transplantation may not reverse the cognitive deficits associated with MHE. We performed here an updated review on epidemiology, burden and quality of life, neuropsychological testing, neuroimaging, neurophysiology and therapy in subjects with MHE.

  9. Unoriented Minimal Type 0 Strings

    CERN Document Server

    Carlisle, J E; Carlisle, James E; Johnson, Clifford V

    2004-01-01

    We define a family of string equations with perturbative expansions that admit an interpretation as an unoriented minimal string theory with background D-branes and R-R fluxes. The theory also has a well-defined non-perturbative sector and we expect it to have a continuum interpretation as an orientifold projection of the non-critical type~0A string for \\hat{c}=0, the (2,4) model. There is a second perturbative region which is consistent with an interpretation in terms of background R-R fluxes. We identify a natural parameter in the formulation that we speculate may have an interpretation as characterizing the contribution of a new type of background D-brane. There is a non-perturbative map to a family of string equations which we expect to be the \\hat{c}=0 type 0B string. The map exchanges D-branes and R-R fluxes. We present the general structure of the string equations for the (2,4k) type 0A models.

  10. Cosine tuning minimizes motor errors.

    Science.gov (United States)

    Todorov, Emanuel

    2002-06-01

    Cosine tuning is ubiquitous in the motor system, yet a satisfying explanation of its origin is lacking. Here we argue that cosine tuning minimizes expected errors in force production, which makes it a natural choice for activating muscles and neurons in the final stages of motor processing. Our results are based on the empirically observed scaling of neuromotor noise, whose standard deviation is a linear function of the mean. Such scaling predicts a reduction of net force errors when redundant actuators pull in the same direction. We confirm this prediction by comparing forces produced with one versus two hands and generalize it across directions. Under the resulting neuromotor noise model, we prove that the optimal activation profile is a (possibly truncated) cosine--for arbitrary dimensionality of the workspace, distribution of force directions, correlated or uncorrelated noise, with or without a separate cocontraction command. The model predicts a negative force bias, truncated cosine tuning at low muscle cocontraction levels, and misalignment of preferred directions and lines of action for nonuniform muscle distributions. All predictions are supported by experimental data.

  11. Study of constrained minimal supersymmetry

    CERN Document Server

    Kane, G L; Roszkowski, Leszek; Wells, J D; Chris Kolda; Leszek Roszkowski; James D Wells

    1994-01-01

    Taking seriously phenomenological indications for supersymmetry, we have made a detailed study of unified minimal SUSY, including effects at the few percent level in a consistent fashion. We report here a general analysis without choosing a particular unification gauge group. We find that the encouraging SUSY unification results of recent years do survive the challenge of a more complete and accurate analysis. Taking into account effects at the 5-10% level leads to several improvements of previous results, and allows us to sharpen our predictions for SUSY in the light of unification. We perform a thorough study of the parameter space. The results form a well-defined basis for comparing the physics potential of different facilities. Very little of the acceptable parameter space has been excluded by LEP or FNAL so far, but a significant fraction can be covered when these accelerators are upgraded. A number of initial applications to the understanding of the SUSY spectrum, detectability of SUSY at LEP II or FNAL...

  12. Inflation in non-minimal matter-curvature coupling theories

    CERN Document Server

    Gomes, Cláudio; Bertolami, Orfeu

    2016-01-01

    We study inflationary scenarios driven by a scalar field in the presence of a non-minimal coupling between matter and curvature. We show that the Friedmann equation can be significantly modified when the energy density during inflation exceeds a critical value determined by the non-minimal coupling, which in turn may considerably modify the spectrum of primordial perturbations and the inflationary dynamics. In particular, we show that these models are characterised by a consistency relation between the tensor-to-scalar ratio and the tensor spectral index that can differ significantly from the predictions of general relativity. We also give examples of observational predictions for some of the most commonly considered potentials and use the results of the Planck collaboration to set limits on the scale of the non-minimal coupling.

  13. Constraining non-minimally coupled tachyon fields by Noether symmetry

    CERN Document Server

    de Souza, Rudinei C

    2008-01-01

    A model for a spatially flat homogeneous and isotropic Universe whose gravitational sources are a pressureless matter field and a tachyon field non-minimally coupled to the gravitational field is analyzed. Noether symmetry is used to find the expressions for the potential density and for the coupling function, and it is shown that both must be exponential functions of the tachyon field. Two cosmological solutions are investigated: (i) for the early Universe whose only source of the gravitational field is a non-minimally coupled tachyon field which behaves as an inflaton and leads to an exponential accelerated expansion and (ii) for the late Universe whose gravitational sources are a pressureless matter field and a non-minimally coupled tachyon field which plays the role of dark energy and is the responsible of the decelerated-accelerated transition period.

  14. Global regularity for minimal sets and counterexamples

    CERN Document Server

    Liang, Xiangyu

    2011-01-01

    We discuss the global regularity for 2 dimensional minimal sets, that is, whether all global minimal sets in $\\R^n$ are cones or not. Every minimal set looks like a minimal cone $C$ at infinity, hence the main point is to use the topological properties of a minimal set at large scale to control its topology at smaller scales. Such arguments depend on the cone $C$, thus we have to discuss them one by one. Recall that this is the idea to prove that 1-dimensional Almgren-minimal sets in $\\R^n$, and 2-dimensional Mumford-Shah minimal sets in $\\R^3$ are cones. In this article we discuss three types of 2-dimensional minimal sets: Almgren-minimal set in $\\R^3$ whose blow-in limit is a $\\T$ set; topological minimal sets in $\\R^4$ whose blow-in limit is a $\\T$ set; and Almgren minimal sets in $\\R^4$ whose blow-in limit is the union $P_\\theta$ of two almost orthogonal planes. For the first one we eliminate an existing potential counterexample that was proposed by several people, and show that a real counterexample shou...

  15. Minimal models of multidimensional computations.

    Directory of Open Access Journals (Sweden)

    Jeffrey D Fitzgerald

    2011-03-01

    Full Text Available The multidimensional computations performed by many biological systems are often characterized with limited information about the correlations between inputs and outputs. Given this limitation, our approach is to construct the maximum noise entropy response function of the system, leading to a closed-form and minimally biased model consistent with a given set of constraints on the input/output moments; the result is equivalent to conditional random field models from machine learning. For systems with binary outputs, such as neurons encoding sensory stimuli, the maximum noise entropy models are logistic functions whose arguments depend on the constraints. A constraint on the average output turns the binary maximum noise entropy models into minimum mutual information models, allowing for the calculation of the information content of the constraints and an information theoretic characterization of the system's computations. We use this approach to analyze the nonlinear input/output functions in macaque retina and thalamus; although these systems have been previously shown to be responsive to two input dimensions, the functional form of the response function in this reduced space had not been unambiguously identified. A second order model based on the logistic function is found to be both necessary and sufficient to accurately describe the neural responses to naturalistic stimuli, accounting for an average of 93% of the mutual information with a small number of parameters. Thus, despite the fact that the stimulus is highly non-Gaussian, the vast majority of the information in the neural responses is related to first and second order correlations. Our results suggest a principled and unbiased way to model multidimensional computations and determine the statistics of the inputs that are being encoded in the outputs.

  16. Minimization of the k-th eigenvalue of the Dirichlet Laplacian

    Science.gov (United States)

    Bucur, Dorin

    2012-12-01

    For every {k in {N}}, we prove the existence of a quasi-open set minimizing the k-th eigenvalue of the Dirichlet Laplacian among all sets of prescribed Lebesgue measure. Moreover, we prove that every minimizer is bounded and has a finite perimeter. The key point is the observation that such quasi-open sets are shape subsolutions for an energy minimizing free boundary problem.

  17. Model Arrhenius untuk Pendugaan Laju Respirasi Brokoli Terolah Minimal

    Directory of Open Access Journals (Sweden)

    Nurul Imamah

    2016-04-01

    Full Text Available Minimally processed broccoli are perishable product because it still has some metabolism process during the storage period. One of the metabolism process is respiration. Respiration rate is varied depend on the commodity and storage temperature. The purpose of this research are: to review the respiration pattern of minimally processed broccoli during storage period, to study the effect of storage temperature to respiration rate, and to review the correlation between respiration rate and temperature based on Arrhenius model. Broccoli from farming organization “Agro Segar” was processed minimally and then measure the respiration rate. Closed system method is used to measure O2 and CO2 concentration. Minimally processed broccoli is stored at a temperature of 0oC, 5oC, 10oC and 15oC. The experimental design used was completely randomized design of the factors to analyze the rate of respiration. The result shows that broccoli is a climacteric vegetable. It is indicated by the increasing of O2 consumption and CO2 production during senescence phase. The respiration rate increase as high as the increasing of temperature storage. Models Arrhenius can describe correlation between respiration rate and temperature with R2 = 0.953-0.947. The constant value of activation energy (Eai and pre-exponential factor (Roi from Arrhenius model can be used to predict the respiration rate of minimally processed broccoli in every storage temperature

  18. Waste minimization and pollution prevention awareness plan. Revision A

    Energy Technology Data Exchange (ETDEWEB)

    Smith, G.; Hall, R.L.

    1991-05-03

    The purpose of this plan is to establish the Pinellas Plant Waste Minimization and Pollution Prevention Awareness Program. The plan specifies those activities and methods that will be employed to reduce the quantity and toxicity of wastes generated at the site. It is intended to satisfy the Department of Energy (DOE) and other legal requirements that are discussed in Section 1.3. A Waste Minimization Program is an organized, comprehensive, and continual effort to systematically reduce waste generation. The Waste Minimization and Pollution Prevention Awareness Program is designed to eliminate or minimize pollutant releases to all environmental media from all aspects of the site`s operations. These efforts offer increased protection of public health and the environment. Sections of this report describe: Background; Resources; Policy; Strategy, objectives, and goals; Organization and staff responsibilities; Cost accounting; Waste assessments; Waste minimization techniques; Training, awareness, and incentives; Tracking and reporting systems; Quality assurance; Information exchange and outreach; Technology transfer; Research and development; and Program evaluation.

  19. Cultural change and support of waste minimization

    Energy Technology Data Exchange (ETDEWEB)

    Boylan, M.S. [EG and G Idaho, Inc., Idaho Falls, ID (United States). Idaho National Engineering Lab.

    1991-12-31

    The process of bringing a subject like pollution prevention to top of mind awareness, where designed to prevent waste becomes part of business as usual, is called cultural change. With Department of Energy orders and management waste minimization commitment statements on file, the REAL work is just beginning at the Idaho National Engineering Laboratory (INEL); shaping the attitudes of 11,000+ employees. The difficulties of such a task are daunting. The 890 square mile INEL site and in-town support offices mean a huge diversity of employee jobs and waste streams; from cafeteria and auto maintenance wastes to high-level nuclear waste casks. INEL is pursuing a three component cultural change strategy: training, publicity, and public outreach. To meet the intent of DOE orders, all INEL employees are slated to receive pollution prevention orientation training. More technical training is given to targeted groups like purchasing and design engineering. To keep newly learned pollution prevention concepts top-of-mind, extensive site-wide publicity is being developed and conducted, culminating in the April Pollution Prevention Awareness Week coinciding with Earth Day 1992. Finally, news of INEL pollution prevention successes is shared with the public to increase their overall environmental awareness and their knowledge of INEL activities. An important added benefit is the sense of pride the program instills in INEL employees to have their successes displayed so publicly.

  20. Quantum Minimal Length and Transplanckian Photons

    CERN Document Server

    Lubo, M

    2000-01-01

    In this paper we first give arguments supporting the idea that a B.T.Z black hole can face a transplankian problem even when its mass is small. K.M.M quantum theory is applied to the Hawking evaporation of the Schwarzchild and B.T.Z black holes. Working in the physically safe quasi position representation, we argue that the oscillating term present in a previous analysis is removed so that actually one doesn't need an average procedure. We expand the s wave function as the exponential of a series in the minimal length of the new quantum theory. This reduces an infinite order differential equation to a numerable set of finite order ones. We obtain the striking result that the infinity of arbitrary constants induced by the order of the wave equation has no physical meaning due to normalization. We finally construct gaussian wave pacqets and study their trajectories. We suggest a quantitative description of the non locality zone and its dependance on the K.M.M energy scale. Potential incidences on unitarity are ...

  1. Phenomenology in minimal theory of massive gravity

    CERN Document Server

    De Felice, Antonio

    2015-01-01

    We investigate the minimal theory of massive gravity (MTMG) recently introduced. After reviewing the original construction based on its Hamiltonian in the vielbein formalism, we reformulate it in terms of its Lagrangian in both the vielbein and the metric formalisms. It then becomes obvious that, unlike previous attempts in the literature, not only the potential but also the kinetic structure of the action is modified from the de Rham-Gabadadze-Tolley (dRGT) massive gravity theory. We confirm that the number of physical degrees of freedom in MTMG is two at fully nonlinear level. This proves the absence of various possible pathologies such as superluminality, acausality and strong coupling. Afterwards, we discuss the phenomenology of MTMG in the presence of a dust fluid. We find that on a flat homogeneous and isotropic background we have two branches. One of them (self-accelerating branch) naturally leads to acceleration without the genuine cosmological constant or dark energy. For this branch both the scalar ...

  2. The infrared dynamics of Minimal Walking Technicolor

    CERN Document Server

    Del Debbio, Luigi; Patella, Agostino; Pica, Claudio; Rago, Antonio

    2010-01-01

    We study the gauge sector of Minimal Walking Technicolor, which is an SU(2) gauge theory with nf=2 flavors of Wilson fermions in the adjoint representation. Numerical simulations are performed on lattices Nt x Ns^3, with Ns ranging from 8 to 16 and Nt=2Ns, at fixed \\beta=2.25, and varying the fermion bare mass m0, so that our numerical results cover the full range of fermion masses from the quenched region to the chiral limit. We present results for the string tension and the glueball spectrum. A comparison of mesonic and gluonic observables leads to the conclusion that the infrared dynamics is given by an SU(2) pure Yang-Mills theory with a typical energy scale for the spectrum sliding to zero with the fermion mass. The typical mesonic mass scale is proportional to, and much larger than this gluonic scale. Our findings are compatible with a scenario in which the massless theory is conformal in the infrared. An analysis of the scaling of the string tension with the fermion mass towards the massless limit allo...

  3. Torsion gravity with non-minimally coupled fermionic field: some cosmological models

    CERN Document Server

    Vignolo, Stefano; Fabbri, Luca

    2014-01-01

    We investigate some cosmological models arising from a non-minimal coupling of a fermionic field to gravity in the geometrical setting of Einstein-Cartan-Sciama-Kibble gravity. The role played by the non-minimal coupling together with torsion in facing problems such as cosmological singularity, inflation and dark energy is discussed.

  4. Discontinuous Galerkin Method for Total Variation Minimization on one-dimensional Inpainting Problem

    CERN Document Server

    Wang, Xijian

    2011-01-01

    This paper is concerned with the numerical minimization of energy functionals in $BV(\\Omega)$ (the space of bounded variation functions) involving total variation for gray-scale 1-dimensional inpainting problem. Applications are shown by finite element method and discontinuous Galerkin method for total variation minimization. We include the numerical examples which show the different recovery image by these two methods.

  5. Relativistic Approach to the Hydrogen Atom in a Minimal Length Scenario

    Energy Technology Data Exchange (ETDEWEB)

    Francisco, Ronald Oliveira; Oakes, Thiago Luiz Antonacci; Fabris, Julio Cesar; Nogueira, Jose Alexandre, E-mail: jose.nogueira@ufes.br [Universidade Federal do Espirito Santo (UFES), Vitoria, ES (Brazil). Departamento de Fisica

    2014-07-01

    We show that relativistic contributions to the ground-state energy of the hydrogen atom from a minimal length introduced by a Lorentz-covariant algebra are more important than non-relativistic contributions; the nonrelativistic approach is therefore unsuitable. We compare our result with experimental data to estimate an upper bound of the order 10{sup -20}m for the minimal length. (author)

  6. Existence of Dyons in Minimally Gauged Skyrme Model via Constrained Minimization

    CERN Document Server

    Gao, Zhifeng

    2011-01-01

    We prove the existence of electrically and magnetically charged particlelike static solutions, known as dyons, in the minimally gauged Skyrme model developed by Brihaye, Hartmann, and Tchrakian. The solutions are spherically symmetric, depend on two continuous parameters, and carry unit monopole and magnetic charges but continuous Skyrme charge and non-quantized electric charge induced from the 't Hooft electromagnetism. The problem amounts to obtaining a finite-energy critical point of an indefinite action functional, arising from the presence of electricity and the Minkowski spacetime signature. The difficulty with the absence of the Higgs field is overcome by achieving suitable strong convergence and obtaining uniform decay estimates at singular boundary points so that the negative sector of the action functional becomes tractable.

  7. On o-minimal homotopy groups

    CERN Document Server

    Baro, Elias

    2008-01-01

    We work over an o-minimal expansion of a real closed field. The o-minimal homotopy groups of a definable set are defined naturally using definable continuous maps. We prove that any two semialgebraic maps which are definably homotopic are also semialgebraically homotopic. This result together with the study of semialgebraic homotopy done by H. Delfs and M. Knebusch allows us to develop an o-minimal homotopy theory. In particular, we obtain o-minimal versions of the Hurewicz theorems and the Whitehead theorem.

  8. Energy and the Environment

    Science.gov (United States)

    Ford, Davis L.

    2014-07-01

    * The world is currently in an energy transformation. * Fossil fuels extraction technology is resulting in a worldwide exponential increase in the production of oil and gas. * Water may be our most precious natural resource. * What is the role of renewable energy? * How do we maximize world energy production and concurrently minimize environmental impacts?

  9. Contemporary review of minimally invasive pancreaticoduodenectomy.

    Science.gov (United States)

    Dai, Rui; Turley, Ryan S; Blazer, Dan G

    2016-12-27

    To assess the current literature describing various minimally invasive techniques for and to review short-term outcomes after minimally invasive pancreaticoduodenectomy (PD). PD remains the only potentially curative treatment for periampullary malignancies, including, most commonly, pancreatic adenocarcinoma. Minimally invasive approaches to this complex operation have begun to be increasingly reported in the literature and are purported by some to reduce the historically high morbidity of PD associated with the open technique. In this systematic review, we have searched the literature for high-quality publications describing minimally invasive techniques for PD-including laparoscopic, robotic, and laparoscopic-assisted robotic approaches (hybrid approach). We have identified publications with the largest operative experiences from well-known centers of excellence for this complex procedure. We report primarily short term operative and perioperative results and some short term oncologic endpoints. Minimally invasive techniques include laparoscopic, robotic and hybrid approaches and each of these techniques has strong advocates. Consistently, across all minimally invasive modalities, these techniques are associated less intraoperative blood loss than traditional open PD (OPD), but in exchange for longer operating times. These techniques are relatively equivalent in terms of perioperative morbidity and short term oncologic outcomes. Importantly, pancreatic fistula rate appears to be comparable in most minimally invasive series compared to open technique. Impact of minimally invasive technique on length of stay is mixed compared to some traditional open series. A few series have suggested that initiation of and time to adjuvant therapy may be improved with minimally invasive techniques, however this assertion remains controversial. In terms of short-terms costs, minimally invasive PD is significantly higher than that of OPD. Minimally invasive approaches to PD show

  10. Minimizing the mass of a potential railgun power supply

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, D.E.; Noel, A.P.; Clements, W.D. (IAP Research, Inc., Dayton, OH (United States))

    1991-01-01

    This paper reports on the design of a pulsed power supply to deliver 5 MJ at 1 MA at 1 shot per second to a railgun. The supply stores energy at low current in the primary of the hydrogen-cooled transformer. A switch opens the primary circuit to transfer energy to the secondary, stepping the current up to 1 MA. The authors are studying the relationship between the transformer and switch to determine how the total power supply mass can be minimized. Vacuum interrupters and gate-turn-off thyristors are used in the switch. Switch mass dominates the system, accounting for 85% of the total mass. The switch must absorb the uncoupled energy of the transformer. Low transformer coupling requires large capacitors. Even with high coupling, capacitors account for 75 to 85% of the switch mass. If transformer coupling increases, the uncoupled energy decreases, resulting in low capacitor mass.

  11. Minimization of power consumption during charging of superconducting accelerating cavities

    Energy Technology Data Exchange (ETDEWEB)

    Bhattacharyya, Anirban Krishna, E-mail: anirban.bhattacharyya@physics.uu.se; Ziemann, Volker; Ruber, Roger; Goryashko, Vitaliy

    2015-11-21

    The radio frequency cavities, used to accelerate charged particle beams, need to be charged to their nominal voltage after which the beam can be injected into them. The standard procedure for such cavity filling is to use a step charging profile. However, during initial stages of such a filling process a substantial amount of the total energy is wasted in reflection for superconducting cavities because of their extremely narrow bandwidth. The paper presents a novel strategy to charge cavities, which reduces total energy reflection. We use variational calculus to obtain analytical expression for the optimal charging profile. Energies, reflected and required, and generator peak power are also compared between the charging schemes and practical aspects (saturation, efficiency and gain characteristics) of power sources (tetrodes, IOTs and solid state power amplifiers) are also considered and analysed. The paper presents a methodology to successfully identify the optimal charging scheme for different power sources to minimize total energy requirement.

  12. Minimization of power consumption during charging of superconducting accelerating cavities

    Science.gov (United States)

    Bhattacharyya, Anirban Krishna; Ziemann, Volker; Ruber, Roger; Goryashko, Vitaliy

    2015-11-01

    The radio frequency cavities, used to accelerate charged particle beams, need to be charged to their nominal voltage after which the beam can be injected into them. The standard procedure for such cavity filling is to use a step charging profile. However, during initial stages of such a filling process a substantial amount of the total energy is wasted in reflection for superconducting cavities because of their extremely narrow bandwidth. The paper presents a novel strategy to charge cavities, which reduces total energy reflection. We use variational calculus to obtain analytical expression for the optimal charging profile. Energies, reflected and required, and generator peak power are also compared between the charging schemes and practical aspects (saturation, efficiency and gain characteristics) of power sources (tetrodes, IOTs and solid state power amplifiers) are also considered and analysed. The paper presents a methodology to successfully identify the optimal charging scheme for different power sources to minimize total energy requirement.

  13. Energy and Emissions at EPA

    Science.gov (United States)

    To demonstrate its leadership in energy and environmental stewardship, EPA is committed to managing its own facilities and operations in a way that minimizes greenhouse gas (GHG) emissions and energy use.

  14. Minimization of Fuzzy Finite Generalized Automata

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Some concepts in Fuzzy Generalized Automata (FGA) are established. Then an important new algorithm which would calculate the minimal FGA is given. The new algorithm is composed of two parts: the first is called E-reduction which contracts equivalent states, and the second is called RE-reduction which removes retrievable states. Finally an example is given to illuminate the algorithm of minimization.

  15. The relative volume growth of minimal submanifolds

    DEFF Research Database (Denmark)

    Markvorsen, Steen; Palmer, V.

    2002-01-01

    The volume growth of certain well-defined subsets of minimal submanifolds in riemannian spaces are compared with the volume growth of balls and spheres ill space forms of constant curvature.......The volume growth of certain well-defined subsets of minimal submanifolds in riemannian spaces are compared with the volume growth of balls and spheres ill space forms of constant curvature....

  16. Minimal Exit Trajectories with Optimum Correctional Manoeuvres

    Directory of Open Access Journals (Sweden)

    T. N. Srivastava

    1980-10-01

    Full Text Available Minimal exit trajectories with optimum correctional manoeuvers to a rocket between two coplaner, noncoaxial elliptic orbits in an inverse square gravitational field have been investigated. Case of trajectories with no correctional manoeuvres has been analysed. In the end minimal exit trajectories through specified orbital terminals are discussed and problem of ref. (2 is derived as a particular case.

  17. Phenomenology in minimal theory of massive gravity

    Energy Technology Data Exchange (ETDEWEB)

    Felice, Antonio De [Yukawa Institute for Theoretical Physics, Kyoto University,606-8502, Kyoto (Japan); Mukohyama, Shinji [Yukawa Institute for Theoretical Physics, Kyoto University,606-8502, Kyoto (Japan); Kavli Institute for the Physics and Mathematics of the Universe (WPI), University of Tokyo,277-8583, Chiba (Japan)

    2016-04-15

    We investigate the minimal theory of massive gravity (MTMG) recently introduced. After reviewing the original construction based on its Hamiltonian in the vielbein formalism, we reformulate it in terms of its Lagrangian in both the vielbein and the metric formalisms. It then becomes obvious that, unlike previous attempts in the literature of Lorentz-violating massive gravity, not only the potential but also the kinetic structure of the action is modified from the de Rham-Gabadadze-Tolley (dRGT) massive gravity theory. We confirm that the number of physical degrees of freedom in MTMG is two at fully nonlinear level. This proves the absence of various possible pathologies such as superluminality, acausality and strong coupling. Afterwards, we discuss the phenomenology of MTMG in the presence of a dust fluid. We find that on a flat homogeneous and isotropic background we have two branches. One of them (self-accelerating branch) naturally leads to acceleration without the genuine cosmological constant or dark energy. For this branch both the scalar and the vector modes behave exactly as in general relativity (GR). The phenomenology of this branch differs from GR in the tensor modes sector, as the tensor modes acquire a non-zero mass. Hence, MTMG serves as a stable nonlinear completion of the self-accelerating cosmological solution found originally in dRGT theory. The other branch (normal branch) has a dynamics which depends on the time-dependent fiducial metric. For the normal branch, the scalar mode sector, even though as in GR only one scalar mode is present (due to the dust fluid), differs from the one in GR, and, in general, structure formation will follow a different phenomenology. The tensor modes will be massive, whereas the vector modes, for both branches, will have the same phenomenology as in GR.

  18. Minimal change disease: a CD80 podocytopathy?

    Science.gov (United States)

    Ishimoto, Takuji; Shimada, Michiko; Araya, Carlos E; Huskey, Janna; Garin, Eduardo H; Johnson, Richard J

    2011-07-01

    Minimal change disease is the most common nephrotic syndrome in children. Although the etiology of minimal change disease remains to be elucidated, it has been postulated that it is the result of a circulating T-cell factor that causes podocyte cytoskeleton disorganization leading to increased glomerular capillary permeability and/or changes in glomerular basement membrane heparan sulfate glycosaminoglycans resulting in proteinuria. Minimal change disease has been associated with allergies and Hodgkin disease. Consistent with these associations, a role for interleukin-13 with minimal change disease has been proposed. Furthermore, studies evaluating podocytes also have evolved. Recently, increased expression of CD80 (also termed B7-1) on podocytes was identified as a mechanism for proteinuria. CD80 is inhibited by binding to CTLA-4, which is expressed on regulatory T cells. Recently, we showed that urinary CD80 is increased in minimal change disease patients and limited studies have suggested that it is not commonly present in the urine of patients with other glomerular diseases. Interleukin-13 or microbial products via Toll-like receptors could be factors that induce CD80 expression on podocytes. CTLA-4 appears to regulate CD80 expression in podocytes, and to be altered in minimal change disease patients. These findings lead us to suggest that proteinuria in minimal change disease is caused by persistent CD80 expression in podocytes, possibly initiated by stimulation of these cells by antigens or cytokines.

  19. Theories of minimalism in architecture: Post scriptum

    Directory of Open Access Journals (Sweden)

    Stevanović Vladimir

    2012-01-01

    Full Text Available Owing to the period of intensive development in the last decade of XX century, architectural phenomenon called Minimalism in Architecture was remembered as the Style of the Nineties, which is characterized, morphologically speaking, by simplicity and formal reduction. Simultaneously with its development in practice, on a theoretical level several dominant interpretative models were able to establish themselves. The new millennium and time distance bring new problems; therefore this paper represents a discussion on specific theorization related to Minimalism in Architecture that can bear the designation of post scriptum, because their development starts after the constitutional period of architectural minimalist discourse. In XXI century theories, the problem of definition of minimalism remains important topic, approached by theorists through resolving on the axis: Modernism - Minimal Art - Postmodernism - Minimalism in Architecture. With regard to this, analyzed texts can be categorized in two groups: 1 texts of affirmative nature and historical-associative approach in which minimalism is identified with anything that is simple and reduced, in an idealizing manner, relied mostly on the existing hypotheses; 2 critically oriented texts, in which authors reconsider adequacy of the very term 'minimalism' in the context of architecture and take a metacritical attitude towards previous texts.

  20. An algorithm for constructing minimal order inverses

    Science.gov (United States)

    Patel, R. V.

    1976-01-01

    In this paper an algorithm is presented for constructing minimal order inverses of linear, time invariant, controllable and observable, multivariable systems. By means of simple matrix operations, a 'state-overdescribed' system is first constructed which is an inverse of the given multivariable system. A simple Gauss-Jordan type reduction procedure is then used to remove the redundancy in the state vector of the inverse system to obtain a minimal order inverse. When the given multivariable system is not invertible, the algorithm enables a minimal order inverse of an invertible subsystem to be constructed. Numerical examples are given to illustrate the use of the algorithm.

  1. Minimal covariant observables identifying all pure states

    Energy Technology Data Exchange (ETDEWEB)

    Carmeli, Claudio, E-mail: claudio.carmeli@gmail.com [D.I.M.E., Università di Genova, Via Cadorna 2, I-17100 Savona (Italy); I.N.F.N., Sezione di Genova, Via Dodecaneso 33, I-16146 Genova (Italy); Heinosaari, Teiko, E-mail: teiko.heinosaari@utu.fi [Turku Centre for Quantum Physics, Department of Physics and Astronomy, University of Turku (Finland); Toigo, Alessandro, E-mail: alessandro.toigo@polimi.it [Dipartimento di Matematica, Politecnico di Milano, Piazza Leonardo da Vinci 32, I-20133 Milano (Italy); I.N.F.N., Sezione di Milano, Via Celoria 16, I-20133 Milano (Italy)

    2013-09-02

    It has been recently shown by Heinosaari, Mazzarella and Wolf (2013) [1] that an observable that identifies all pure states of a d-dimensional quantum system has minimally 4d−4 outcomes or slightly less (the exact number depending on d). However, no simple construction of this type of minimal observable is known. We investigate covariant observables that identify all pure states and have minimal number of outcomes. It is shown that the existence of this kind of observables depends on the dimension of the Hilbert space.

  2. Minimal representations, geometric quantization, and unitarity.

    Science.gov (United States)

    Brylinski, R; Kostant, B

    1994-06-21

    In the framework of geometric quantization we explicitly construct, in a uniform fashion, a unitary minimal representation pio of every simply-connected real Lie group Go such that the maximal compact subgroup of Go has finite center and Go admits some minimal representation. We obtain algebraic and analytic results about pio. We give several results on the algebraic and symplectic geometry of the minimal nilpotent orbits and then "quantize" these results to obtain the corresponding representations. We assume (Lie Go)C is simple.

  3. Laguerre Minimal Surfaces in R3

    Institute of Scientific and Technical Information of China (English)

    Yu Ping SONG; Chang Ping WANG

    2008-01-01

    Laguerre geometry of surfaces in R3 is given in the book of Blaschke,and has been studied by Musso and Nicolodi,Palmer,Li and Wang and other authors.In this paper we study Laguerre minimal surface in 3-dimensional Euclidean space R3.We show that any Laguerre minimal surface in R3 can be constructed by using at most two holomorphic functions.We show also that any Laguerre minimal surface in R3 with constant Laguerre curvature is Laguerre equivalent to a surface with vanishing mean curvature in the 3-dimensional degenerate space R30.

  4. Blackfolds, plane waves and minimal surfaces

    OpenAIRE

    Armas, Jay; Blau, Matthias

    2015-01-01

    Minimal surfaces in Euclidean space provide examples of possible non-compact horizon geometries and topologies in asymptotically flat space-time. On the other hand, the existence of limiting surfaces in the space-time provides a simple mechanism for making these configurations compact. Limiting surfaces appear naturally in a given space-time by making minimal surfaces rotate but they are also inherent to plane wave or de Sitter space-times in which case minimal surfaces can be static and comp...

  5. Minimal free resolutions over complete intersections

    CERN Document Server

    Eisenbud, David

    2016-01-01

    This book introduces a theory of higher matrix factorizations for regular sequences and uses it to describe the minimal free resolutions of high syzygy modules over complete intersections. Such resolutions have attracted attention ever since the elegant construction of the minimal free resolution of the residue field by Tate in 1957. The theory extends the theory of matrix factorizations of a non-zero divisor, initiated by Eisenbud in 1980, which yields a description of the eventual structure of minimal free resolutions over a hypersurface ring. Matrix factorizations have had many other uses in a wide range of mathematical fields, from singularity theory to mathematical physics.

  6. Transience and capacity of minimal submanifolds

    DEFF Research Database (Denmark)

    Markvorsen, Steen; Palmer, V.

    2003-01-01

    We prove explicit lower bounds for the capacity of annular domains of minimal submanifolds P-m in ambient Riemannian spaces N-n with sectional curvatures bounded from above. We characterize the situations in which the lower bounds for the capacity are actually attained. Furthermore we apply...... these bounds to prove that Brownian motion defined on a complete minimal submanifold is transient when the ambient space is a negatively curved Hadamard-Cartan manifold. The proof stems directly from the capacity bounds and also covers the case of minimal submanifolds of dimension m > 2 in Euclidean spaces....

  7. Design and Demonstration of Minimal Lunar Base

    Science.gov (United States)

    Boche-Sauvan, L.; Foing, B. H.; Exohab Team

    2009-04-01

    (Integrated Exploration Study, ESA ESTEC [1,2]). We will focus on the easiest and the soonest way in settling a minimal base immediately operational in scientific experimentation, but not immediately autonomous. It will prepare the next permanent lunar base by assessing its technologies, and give scientific results about the environment. The autonomy will be gained in the evolution of the base, and added equipment. A lunar outpost in a polar region would allow missions longer than 14 days, and a frequent addition of equipments. Moreover, a polar outpost will get both advantages of far-side for simulating direct or indirect communications to Earth and dark-side for observations. The low solar rays incidence may permit having ice in deep craters, which will be beneficial for the evolution of the outpost into a autonomous base. The South Pole, by its position on the edge of the South Pole Aitken (SPA) Basin, will allow different fast new data in analysis mantle samples, easily reachable due to the crater morphology. These samples will constrain the putative Late Heavy Bombarment (LHB). After a robotic sample return mission, a human presence will allow deeper research through well chosen geological samples [6]. In this modular concept, we consider various infrastructure elements: core habitat, EVA, crew mobility, energy supply, recycling module, communication, green house and food production, operations. Many of these elements have already been studied in space agencies' architecture proposals, with the tech-nological possibilities of industrial partners (lunar landers, lunar orbiter, rovers …). A deeper reflection will be therefore done about the core habitat and the laboratory equipment, proposing scientific priority experiments. Each element will be added in a range considering their priority to life support in duration [7]. Considering surface operations, protocols will be specified in the use of certain elements. After a reflexion on the different dependancies and

  8. Design Mixers to Minimize Effects of Erosion and Corrosion Erosion

    Directory of Open Access Journals (Sweden)

    Julian Fasano

    2012-01-01

    Full Text Available A thorough review of the major parameters that affect solid-liquid slurry wear on impellers and techniques for minimizing wear is presented. These major parameters include (i chemical environment, (ii hardness of solids, (iii density of solids, (iv percent solids, (v shape of solids, (vi fluid regime (turbulent, transitional, or laminar, (vii hardness of the mixer's wetted parts, (viii hydraulic efficiency of the impeller (kinetic energy dissipation rates near the impeller blades, (ix impact velocity, and (x impact frequency. Techniques for minimizing the wear on impellers cover the choice of impeller, size and speed of the impeller, alloy selection, and surface coating or coverings. An example is provided as well as an assessment of the approximate life improvement.

  9. Session: Avoiding, minimizing, and mitigating avian and bat impacts

    Energy Technology Data Exchange (ETDEWEB)

    Thelander, Carl; Kerlinger, Paul

    2004-09-01

    This session at the Wind Energy and Birds/Bats workshop consisted of two presentations followed by a discussion/question answer period. The session addressed a variety of questions related to avoiding, minimizing, and mitigating the avian and bat impacts of wind power development including: what has been learned from operating turbines and mitigating impacts where they are unavoidable, such as at Altamont Pass WRA, and should there be mitigation measures such as habitat creation or land conservation where impacts occur. Other impact minimization and mitigation approaches discussed included: location and siting evaluations; options for construction and operation of wind facilities; turbine lighting; and the physical alignment/orientation. Titles and authors of the presentations were: 'Bird Fatalities in the Altamont Pass Wind Resource Area: A Case Study, Part II' by Carl Thelander and 'Prevention and Mitigation of Avian Impacts at Wind Power Facilities' by Paul Kerlinger.

  10. Holographic fluctuations and the principle of minimal complexity

    Energy Technology Data Exchange (ETDEWEB)

    Chemissany, Wissam [Institut für Theoretische Physik, Leibniz Universität Hannover,Appelstr. 2, 30167 Hannover (Germany); Department of Mechanical Engineering, MIT,Cambridge MA 02139 (United States); Osborne, Tobias J. [Institut für Theoretische Physik, Leibniz Universität Hannover,Appelstr. 2, 30167 Hannover (Germany)

    2016-12-14

    We discuss, from a quantum information perspective, recent proposals of Maldacena, Ryu, Takayanagi, van Raamsdonk, Swingle, and Susskind that spacetime is an emergent property of the quantum entanglement of an associated boundary quantum system. We review the idea that the informational principle of minimal complexity determines a dual holographic bulk spacetime from a minimal quantum circuit U preparing a given boundary state from a trivial reference state. We describe how this idea may be extended to determine the relationship between the fluctuations of the bulk holographic geometry and the fluctuations of the boundary low-energy subspace. In this way we obtain, for every quantum system, an Einstein-like equation of motion for what might be interpreted as a bulk gravity theory dual to the boundary system.

  11. Holographic fluctuations and the principle of minimal complexity

    CERN Document Server

    Chemissany, Wissam

    2016-01-01

    We discuss, from a quantum information perspective, recent proposals of Maldacena, Ryu, Takayanagi, van Raamsdonk, Swingle, and Susskind that spacetime is an emergent property of the quantum entanglement of an associated boundary quantum system. We review the idea that the informational principle of minimal complexity determines a dual holographic bulk spacetime from a minimal quantum circuit U preparing a given boundary state from a trivial reference state. We describe how this idea may be extended to determine the relationship between the fluctuations of the bulk holographic geometry and the fluctuations of the boundary low-energy subspace. In this way we obtain, for every quantum system, an Einstein-like equation of motion for what might be interpreted as a bulk gravity theory dual to the boundary system.

  12. Holographic fluctuations and the principle of minimal complexity

    Science.gov (United States)

    Chemissany, Wissam; Osborne, Tobias J.

    2016-12-01

    We discuss, from a quantum information perspective, recent proposals of Maldacena, Ryu, Takayanagi, van Raamsdonk, Swingle, and Susskind that spacetime is an emergent property of the quantum entanglement of an associated boundary quantum system. We review the idea that the informational principle of minimal complexity determines a dual holographic bulk spacetime from a minimal quantum circuit U preparing a given boundary state from a trivial reference state. We describe how this idea may be extended to determine the relationship between the fluctuations of the bulk holographic geometry and the fluctuations of the boundary low-energy subspace. In this way we obtain, for every quantum system, an Einstein-like equation of motion for what might be interpreted as a bulk gravity theory dual to the boundary system.

  13. Minimal Reductions and Cores of Edge Ideals

    CERN Document Server

    Fouli, Louiza

    2010-01-01

    We study minimal reductions of edge ideals of graphs containing a unique even cycle, and determine restrictions on the coefficients of the generators of these minimal reductions. We focus our attention on two special subclasses of edge ideals; the first is edge ideals of even cycles and the second is edge ideals of even cycles with an arbitrary number of whiskers. We prove that $\\rm{core}(I)=\\mathfrak{m} I$, where $I$ is the edge ideal in the corresponding localized polynomial ring and $\\mathfrak{m}$ is the maximal ideal of this ring. Moreover, we show that the core is obtained as a finite intersection of homogeneous minimal reductions in the case of even cycles. The formula for the core does not hold in general for the edge ideal of any graph and we provide a counterexample. In particular, we show in this example that the core is not obtained as a finite intersection of general minimal reductions.

  14. Minimal regular 2-graphs and applications

    Institute of Scientific and Technical Information of China (English)

    FAN; Hongbing; LIU; Guizhen; LIU; Jiping

    2006-01-01

    A 2-graph is a hypergraph with edge sizes of at most two. A regular 2-graph is said to be minimal if it does not contain a proper regular factor. Let f2(n) be the maximum value of degrees over all minimal regular 2-graphs of n vertices. In this paper, we provide a structure property of minimal regular 2-graphs, and consequently, prove that f2(n) = n+3-i/3where 1 ≤i≤6, i=n (mod 6) andn≥ 7, which solves a conjecture posed by Fan, Liu, Wu and Wong. As applications in graph theory, we are able to characterize unfactorable regular graphs and provide the best possible factor existence theorem on degree conditions. Moreover, f2(n) and the minimal 2-graphs can be used in the universal switch box designs, which originally motivated this study.

  15. Waste minimization and pollution prevention awareness plan

    Energy Technology Data Exchange (ETDEWEB)

    1991-05-31

    The purpose of this plan is to document the Lawrence Livermore National Laboratory (LLNL) Waste Minimization and Pollution Prevention Awareness Program. The plan specifies those activities and methods that are or will be employed to reduce the quantity and toxicity of wastes generated at the site. The intent of this plan is to respond to and comply with (DOE's) policy and guidelines concerning the need for pollution prevention. The Plan is composed of a LLNL Waste Minimization and Pollution Prevention Awareness Program Plan and, as attachments, Program- and Department-specific waste minimization plans. This format reflects the fact that waste minimization is considered a line management responsibility and is to be addressed by each of the Programs and Departments. 14 refs.

  16. Minimally Invasive Transcatheter Aortic Valve Replacement (TAVR)

    Medline Plus

    Full Text Available Watch a Broward Health surgeon perform a minimally invasive Transcatheter Aortic Valve Replacement (TAVR) Click Here to view the BroadcastMed, Inc. Privacy Policy and Legal Notice © 2017 BroadcastMed, Inc. ...

  17. Biharmonic Maps and Laguerre Minimal Surfaces

    Directory of Open Access Journals (Sweden)

    Yusuf Abu Muhanna

    2013-01-01

    Full Text Available A Laguerre surface is known to be minimal if and only if its corresponding isotropic map is biharmonic. For every Laguerre surface Φ is its associated surface Ψ=1+u2Φ, where u lies in the unit disk. In this paper, the projection of the surface Ψ associated to a Laguerre minimal surface is shown to be biharmonic. A complete characterization of Ψ is obtained under the assumption that the corresponding isotropic map of the Laguerre minimal surface is harmonic. A sufficient and necessary condition is also derived for Ψ to be a graph. Estimates of the Gaussian curvature to the Laguerre minimal surface are obtained, and several illustrative examples are given.

  18. Proton Decay in Minimal Supersymmetric SU(5)

    OpenAIRE

    Bajc, Borut; Perez, Pavel Fileviez; Senjanovic, Goran

    2002-01-01

    We systematically study proton decay in the minimal supersymmetric SU(5) grand unified theory. We find that although the available parameter space of soft masses and mixings is quite constrained, the theory is still in accord with experiment.

  19. Genetic algorithms for minimal source reconstructions

    Energy Technology Data Exchange (ETDEWEB)

    Lewis, P.S.; Mosher, J.C.

    1993-12-01

    Under-determined linear inverse problems arise in applications in which signals must be estimated from insufficient data. In these problems the number of potentially active sources is greater than the number of observations. In many situations, it is desirable to find a minimal source solution. This can be accomplished by minimizing a cost function that accounts from both the compatibility of the solution with the observations and for its ``sparseness``. Minimizing functions of this form can be a difficult optimization problem. Genetic algorithms are a relatively new and robust approach to the solution of difficult optimization problems, providing a global framework that is not dependent on local continuity or on explicit starting values. In this paper, the authors describe the use of genetic algorithms to find minimal source solutions, using as an example a simulation inspired by the reconstruction of neural currents in the human brain from magnetoencephalographic (MEG) measurements.

  20. Cigarette price minimization strategies used by adults

    National Research Council Canada - National Science Library

    Pesko, Michael F; Kruger, Judy; Hyland, Andrew

    2012-01-01

    .... We explored use of cigarette price minimization strategies, such as purchasing cartons of cigarettes, purchasing in states with lower after-tax cigarette prices, and purchasing on the Internet...

  1. Minimally Invasive Transcatheter Aortic Valve Replacement (TAVR)

    Medline Plus

    Full Text Available Watch a Broward Health surgeon perform a minimally invasive Transcatheter Aortic Valve Replacement (TAVR) Click Here to view the BroadcastMed, Inc. Privacy Policy and Legal Notice © 2017 BroadcastMed, Inc. ...

  2. Minimally processed fruit salad enriched with Lactobacillus ...

    African Journals Online (AJOL)

    paula

    2015-06-17

    Jun 17, 2015 ... compounds in the preservation of color ... of probiotic microorganisms in minimally processed fruit. (Rößle et al., 2010a, b; ... MATERIALS AND METHODS ..... (2009). The use of packaging techniques to maintain freshness in.

  3. 2013 Los Alamos National Laboratory Hazardous Waste Minimization Report

    Energy Technology Data Exchange (ETDEWEB)

    Salzman, Sonja L. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); English, Charles J. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-08-24

    Waste minimization and pollution prevention are inherent goals within the operating procedures of Los Alamos National Security, LLC (LANS). The US Department of Energy (DOE) and LANS are required to submit an annual hazardous waste minimization report to the New Mexico Environment Department (NMED) in accordance with the Los Alamos National Laboratory (LANL or the Laboratory) Hazardous Waste Facility Permit. The report was prepared pursuant to the requirements of Section 2.9 of the LANL Hazardous Waste Facility Permit. This report describes the hazardous waste minimization program (a component of the overall Waste Minimization/Pollution Prevention [WMin/PP] Program) administered by the Environmental Stewardship Group (ENV-ES). This report also supports the waste minimization and pollution prevention goals of the Environmental Programs Directorate (EP) organizations that are responsible for implementing remediation activities and describes its programs to incorporate waste reduction practices into remediation activities and procedures. LANS was very successful in fiscal year (FY) 2013 (October 1-September 30) in WMin/PP efforts. Staff funded four projects specifically related to reduction of waste with hazardous constituents, and LANS won four national awards for pollution prevention efforts from the National Nuclear Security Administration (NNSA). In FY13, there was no hazardous, mixedtransuranic (MTRU), or mixed low-level (MLLW) remediation waste generated at the Laboratory. More hazardous waste, MTRU waste, and MLLW was generated in FY13 than in FY12, and the majority of the increase was related to MTRU processing or lab cleanouts. These accomplishments and analysis of the waste streams are discussed in much more detail within this report.

  4. 2016 Los Alamos National Laboratory Hazardous Waste Minimization Report

    Energy Technology Data Exchange (ETDEWEB)

    Salzman, Sonja L. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); English, Charles Joe [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-12-02

    Waste minimization and pollution prevention are goals within the operating procedures of Los Alamos National Security, LLC (LANS). The US Department of Energy (DOE), inclusive of the National Nuclear Security Administration (NNSA) and the Office of Environmental Management, and LANS are required to submit an annual hazardous waste minimization report to the New Mexico Environment Department (NMED) in accordance with the Los Alamos National Laboratory (LANL or the Laboratory) Hazardous Waste Facility Permit. The report was prepared pursuant to the requirements of Section 2.9 of the LANL Hazardous Waste Facility Permit. This report describes the hazardous waste minimization program, which is a component of the overall Pollution Prevention (P2) Program, administered by the Environmental Stewardship Group (EPC-ES). This report also supports the waste minimization and P2 goals of the Associate Directorate of Environmental Management (ADEM) organizations that are responsible for implementing remediation activities and describes its programs to incorporate waste reduction practices into remediation activities and procedures. This report includes data for all waste shipped offsite from LANL during fiscal year (FY) 2016 (October 1, 2015 – September 30, 2016). LANS was active during FY2016 in waste minimization and P2 efforts. Multiple projects were funded that specifically related to reduction of hazardous waste. In FY2016, there was no hazardous, mixed-transuranic (MTRU), or mixed low-level (MLLW) remediation waste shipped offsite from the Laboratory. More non-remediation hazardous waste and MLLW was shipped offsite from the Laboratory in FY2016 compared to FY2015. Non-remediation MTRU waste was not shipped offsite during FY2016. These accomplishments and analysis of the waste streams are discussed in much more detail within this report.

  5. Energy conservation in infants.

    Science.gov (United States)

    Blass, Elliott

    2015-08-01

    Energy acquisition through suckling has been widely studied in rat and human infants. Processes mediating energy conservation, however, have not received the attention that they deserve. This essay, in honor of Professor Jerry Hogan, discusses parallel behaviors used by rat and human mothers to minimize energy loss in their offspring. Parallel mechanisms underlying energy preservation have been identified in rats and humans, suggesting phylogenetic conservation and possibly continuity. This article is part of a Special Issue entitled: In Honor of Jerry Hogan.

  6. Minimally Invasive Osteotomies of the Calcaneus.

    Science.gov (United States)

    Guyton, Gregory P

    2016-09-01

    Osteotomies of the calcaneus are powerful surgical tools, representing a critical component of the surgical reconstruction of pes planus and pes cavus deformity. Modern minimally invasive calcaneal osteotomies can be performed safely with a burr through a lateral incision. Although greater kerf is generated with the burr, the effect is modest, can be minimized, and is compatible with many fixation techniques. A hinged jig renders the procedure more reproducible and accessible. Copyright © 2016 Elsevier Inc. All rights reserved.

  7. Minimal Braid in Applied Symbolic Dynamics

    Institute of Scientific and Technical Information of China (English)

    张成; 张亚刚; 彭守礼

    2003-01-01

    Based on the minimal braid assumption, three-dimensional periodic flows of a dynamical system are reconstructed in the case of unimodal map, and their topological structures are compared with those of the periodic orbits of the Rossler system in phase space through the numerical experiment. The numerical results justify the validity of the minimal braid assumption which provides a suspension from one-dimensional symbolic dynamics in the Poincare section to the knots of three-dimensional periodic flows.

  8. On Quantum Channel Estimation with Minimal Resources

    CERN Document Server

    Zorzi, M; Ferrante, A

    2011-01-01

    We determine the minimal experimental resources that ensure a unique solution in the estimation of trace-preserving quantum channels with both direct and convex optimization methods. A convenient parametrization of the constrained set is used to develop a globally converging Newton-type algorithm that ensures a physically admissible solution to the problem. Numerical simulations are provided to support the results, and indicate that the minimal experimental setting is sufficient to guarantee good estimates.

  9. Minimally Invasive Forefoot Surgery in France.

    Science.gov (United States)

    Meusnier, Tristan; Mukish, Prikesht

    2016-06-01

    Study groups have been formed in France to advance the use of minimally invasive surgery. These techniques are becoming more frequently used and the technique nuances are continuing to evolve. The objective of this article was to advance the awareness of the current trends in minimally invasive surgery for common diseases of the forefoot. The percutaneous surgery at the forefoot is less developed at this time, but also will be discussed.

  10. Ill-Posedness of sublinear minimization problems

    Directory of Open Access Journals (Sweden)

    S. Issa

    2011-04-01

    Full Text Available It is well known that minimization problems involving sublinear regularization terms are ill-posed, in Sobolev spaces. Extended results to spaces of bounded variation functions BV were recently showed in the special case of bounded regularization terms. In this note, a generalization to sublinear regularization is presented in BV spaces. Notice that our results are optimal in the sense that linear regularization leads to well-posed minimization problems in BV spaces.

  11. Lectures on flips and minimal models

    OpenAIRE

    Corti, Alessio; Hacking, Paul; Kollár, János; Lazarsfeld, Robert; Mustaţă, Mircea

    2007-01-01

    This document contains notes from the lectures of Corti, Koll\\'ar, Lazarsfeld, and Musta\\c{t}\\u{a} at the workshop ``Minimal and canonical models in algebraic geometry" at MSRI, Berkeley, April 2007. The lectures give an overview of the recent advances on canonical and minimal models of algebraic varieties obtained by Hacon--McKernan and Birkar--Cascini--Hacon--McKernan.

  12. Two tractable subclasses of minimal unsatisfiable formulas

    Institute of Scientific and Technical Information of China (English)

    赵希顺; 丁德成

    1999-01-01

    The minimal unsatisfiability problem is considered of the propositional formulas in CNF which in the case of variables x1,…, xn consist of n+k clauses including x1V…Vxn and (?) -(X1)V…V(?)xn. It is shown that when k≤4 the minimal unsatisfiability problem can be solved in polynomial time.

  13. The advantages of minimally invasive dentistry.

    Science.gov (United States)

    Christensen, Gordon J

    2005-11-01

    Minimally invasive dentistry, in cases in which it is appropriate, is a concept that preserves dentitions and supporting structures. In this column, I have discussed several examples of minimally invasive dental techniques. This type of dentistry is gratifying for dentists and appreciated by patients. If more dentists would practice it, the dental profession could enhance the public's perception of its honesty and increase its professionalism as well.

  14. L1-norm minimization for quaternion signals

    CERN Document Server

    Wu, Jiasong; Wang, Xiaoqing; Senhadji, Lotfi; Shu, Huazhong

    2012-01-01

    The l1-norm minimization problem plays an important role in the compressed sensing (CS) theory. We present in this letter an algorithm for solving the problem of l1-norm minimization for quaternion signals by converting it to second-order cone programming. An application example of the proposed algorithm is also given for practical guidelines of perfect recovery of quaternion signals. The proposed algorithm may find its potential application when CS theory meets the quaternion signal processing.

  15. Minimalism in Art, Medical Science and Neurosurgery.

    Science.gov (United States)

    Ökten, Ali İhsan

    2016-12-21

    The word ''minimalism'' is a word derived from French the word ''minimum''. Whereas the lexical meaning of minimum is ''the least or the smallest quantity necessary for something'', its expression in mathematics can be described as ''the lowest step a variable number can descend, least, minimal''. Minimalism, which advocates an extreme simplicity of the artistic form, is a current in modern art and music whose origins go to 1960s and which features simplicity and objectivity. Although art, science and philosophy are different disciplines, they support each other from time to time, sometimes they intertwine and sometimes they copy each other. A periodic schools or teaching in one of them can take the others into itself, so, they proceed on their ways empowering each other. It is also true for the minimalism in art and the minimal invasive surgical approaches in science. Concepts like doing with less, avoiding unnecessary materials and reducing the number of the elements in order to increase the effect in the expression which are the main elements of the minimalism in art found their equivalents in medicine and neurosurgery. Their equivalents in medicine or neurosurgery have been to protect the physical integrity of the patient with less iatrogenic injury, minimum damage and the same therapeutic effect in the most effective way and to enable the patient to regain his health in the shortest span of time.

  16. Economic impact of minimally invasive lumbar surgery

    Science.gov (United States)

    Hofstetter, Christoph P; Hofer, Anna S; Wang, Michael Y

    2015-01-01

    Cost effectiveness has been demonstrated for traditional lumbar discectomy, lumbar laminectomy as well as for instrumented and noninstrumented arthrodesis. While emerging evidence suggests that minimally invasive spine surgery reduces morbidity, duration of hospitalization, and accelerates return to activites of daily living, data regarding cost effectiveness of these novel techniques is limited. The current study analyzes all available data on minimally invasive techniques for lumbar discectomy, decompression, short-segment fusion and deformity surgery. In general, minimally invasive spine procedures appear to hold promise in quicker patient recovery times and earlier return to work. Thus, minimally invasive lumbar spine surgery appears to have the potential to be a cost-effective intervention. Moreover, novel less invasive procedures are less destabilizing and may therefore be utilized in certain indications that traditionally required arthrodesis procedures. However, there is a lack of studies analyzing the economic impact of minimally invasive spine surgery. Future studies are necessary to confirm the durability and further define indications for minimally invasive lumbar spine procedures. PMID:25793159

  17. Sequential unconstrained minimization algorithms for constrained optimization

    Science.gov (United States)

    Byrne, Charles

    2008-02-01

    The problem of minimizing a function f(x):RJ → R, subject to constraints on the vector variable x, occurs frequently in inverse problems. Even without constraints, finding a minimizer of f(x) may require iterative methods. We consider here a general class of iterative algorithms that find a solution to the constrained minimization problem as the limit of a sequence of vectors, each solving an unconstrained minimization problem. Our sequential unconstrained minimization algorithm (SUMMA) is an iterative procedure for constrained minimization. At the kth step we minimize the function G_k(x)=f(x)+g_k(x), to obtain xk. The auxiliary functions gk(x):D ⊆ RJ → R+ are nonnegative on the set D, each xk is assumed to lie within D, and the objective is to minimize the continuous function f:RJ → R over x in the set C=\\overline D , the closure of D. We assume that such minimizers exist, and denote one such by \\hat x . We assume that the functions gk(x) satisfy the inequalities 0\\leq g_k(x)\\leq G_{k-1}(x)-G_{k-1}(x^{k-1}), for k = 2, 3, .... Using this assumption, we show that the sequence {f(xk)} is decreasing and converges to f({\\hat x}) . If the restriction of f(x) to D has bounded level sets, which happens if \\hat x is unique and f(x) is closed, proper and convex, then the sequence {xk} is bounded, and f(x^*)=f({\\hat x}) , for any cluster point x*. Therefore, if \\hat x is unique, x^*={\\hat x} and \\{x^k\\}\\rightarrow {\\hat x} . When \\hat x is not unique, convergence can still be obtained, in particular cases. The SUMMA includes, as particular cases, the well-known barrier- and penalty-function methods, the simultaneous multiplicative algebraic reconstruction technique (SMART), the proximal minimization algorithm of Censor and Zenios, the entropic proximal methods of Teboulle, as well as certain cases of gradient descent and the Newton-Raphson method. The proof techniques used for SUMMA can be extended to obtain related results for the induced proximal

  18. Free Energy in Introductory Physics

    Science.gov (United States)

    Prentis, Jeffrey J.; Obsniuk, Michael J.

    2016-01-01

    Energy and entropy are two of the most important concepts in science. For all natural processes where a system exchanges energy with its environment, the energy of the system tends to decrease and the entropy of the system tends to increase. Free energy is the special concept that specifies how to balance the opposing tendencies to minimize energy…

  19. Principles of light energy management

    Science.gov (United States)

    Davis, N.

    1994-01-01

    Six methods used to minimize excess energy effects associated with lighting systems for plant growth chambers are reviewed in this report. The energy associated with wall transmission and chamber operating equipment and the experimental requirements, such as fresh air and internal equipment, are not considered here. Only the energy associated with providing and removing the energy for lighting is considered.

  20. Towards a Real-Time Minimally-Invasive Vascular Intervention Simulation System

    NARCIS (Netherlands)

    Alderliesten, T.; Bosman, P.A.N.; Niessen, W.

    2007-01-01

    Recently, foundations rooted in physics have been laid down for the goal of simulating the propagation of a guide wire inside the vasculature. At the heart of the simulation lies the fundamental task of energy minimization. The energy comes from interaction with the vessel wall and the bending of th

  1. Architecture and energy; Arkitektur og energi

    Energy Technology Data Exchange (ETDEWEB)

    Marsh, R.; Grupe Larsen, V.; Lauring, M.; Christensen, Morten

    2006-07-01

    The aim of this book is to illustrate the interaction between architecture and energy in an overall perspective starting from the new energy requirements. Architects make a lot of form related outlines early in the design process, and these have significant consequences for the energy consumption. Furthermore, the new energy requirements start from an overall evaluation, during which the architectural form is of decisive importance to minimization of the energy consumption. The book focuses on four themes: a) day lighting, which plays a decisive part in relation to our health and wellness inside buildings, b) solar heating; passive solar heating has traditionally been playing an important part in low-energy architecture, c) rough house; choice of materials can both increase and decrease buildings' energy consumption, and d) technology; modern buildings use a number of energy demanding installations, therefore the interaction between technology and energy is examined. (BA)

  2. Minimal Invasive Urologic Surgery and Postoperative Ileus

    Directory of Open Access Journals (Sweden)

    Fouad Aoun

    2015-07-01

    Full Text Available Postoperative ileus (POI is the most common cause of prolonged length of hospital stays (LOS and associated healthcare costs. The advent of minimal invasive technique was a major breakthrough in the urologic landscape with great potential to progress in the future. In the field of gastrointestinal surgery, several studies had reported lower incidence rates for POI following minimal invasive surgery compared to conventional open procedures. In contrast, little is known about the effect of minimal invasive approach on the recovery of bowel motility after urologic surgery. We performed an overview of the potential benefit of minimal invasive approach on POI for urologic procedures. The mechanisms and risk factors responsible for the onset of POI are discussed with emphasis on the advantages of minimal invasive approach. In the urologic field, POI is the main complication following radical cystectomy but it is rarely of clinical significance for other minimal invasive interventions. Laparoscopy or robotic assisted laparoscopic techniques when studied individually may reduce to their own the duration and prevent the onset of POI in a subset of procedures. The potential influence of age and urinary diversion type on postoperative ileus is contradictory in the literature. There is some evidence suggesting that BMI, blood loss, urinary extravasation, existence of a major complication, bowel resection, operative time and transperitoneal approach are independent risk factors for POI. Treatment of POI remains elusive. One of the most important and effective management strategies for patients undergoing radical cystectomy has been the development and use of enhanced recovery programs. An optimal rational strategy to shorten the duration of POI should incorporate minimal invasive approach when appropriate into multimodal fast track programs designed to reduce POI and shorten LOS.

  3. One paramter family of solitons from minimal surfaces

    CERN Document Server

    Dey, Rukmini

    2012-01-01

    In this paper, we discuss a one parameter family of complex Born-Infeld solitons arising from a one parameter family of minimal surfaces. The process enables us to generate a new solution of the B-I equation from a given complex solution of a special type (which are abundant). We illustrate this with many examples. We find that the action or the energy of this family of solitons remains invariant in this family and find that the well-known Lorentz symmetry of the B-I equations is responsible for it.

  4. On the quantum mechanical solutions with minimal length uncertainty

    Science.gov (United States)

    Shababi, Homa; Pedram, Pouria; Chung, Won Sang

    2016-06-01

    In this paper, we study two generalized uncertainty principles (GUPs) including [X,P] = iℏ(1 + βP2j) and [X,P] = iℏ(1 + βP2 + kβ2P4) which imply minimal measurable lengths. Using two momentum representations, for the former GUP, we find eigenvalues and eigenfunctions of the free particle and the harmonic oscillator in terms of generalized trigonometric functions. Also, for the latter GUP, we obtain quantum mechanical solutions of a particle in a box and harmonic oscillator. Finally we investigate the statistical properties of the harmonic oscillator including partition function, internal energy, and heat capacity in the context of the first GUP.

  5. Supersymmetric extension of the minimal dark matter model

    Institute of Scientific and Technical Information of China (English)

    CHANG Xue; LIU Chun; MA Feng-Cai; YANG Shuo

    2012-01-01

    The minimal dark matter model is given a supersymmetric extension.A super SU(2)L quintuplet is introduced with its fermionic neutral component still being the dark matter,and the dark matter mass is about 19.7 TeV.Mass splitting among the quintplet due to supersymmetry particles is found to be negligibly small compared to the electroweak corrections.Other properties of this supersymmetry model are studied,it has the solutions to the PAMELA and Fermi-LAT anomaly,and the predictions in higher energies need further experimental data to verify them.

  6. Noncommutative scalar field minimally coupled to nonsymmetric gravity

    Energy Technology Data Exchange (ETDEWEB)

    Kouadik, S.; Sefai, D. [Laboratory of Mechanic, Physics and Mathematical Modeling Medea University (Algeria)

    2012-06-27

    We construct a non-commutative non symmetric gravity minimally coupled model (the star product only couples matter). We introduce the action for the system considered namely a non-commutative scalar field propagating in a nontrivial gravitational background. We expand the action in powers of the anti-symmetric field and the graviton to second order adopting the assumption that the scalar is weekly coupled to the graviton. We compute the one loop radiative corrections to the self-energy of a scalar particle.

  7. One-Parameter Family of Solitons from Minimal Surfaces

    Indian Academy of Sciences (India)

    Rukmini Dey; Pradip Kumar

    2013-02-01

    In this paper, we discuss a one parameter family of complex Born–Infeld solitons arising from a one parameter family of minimal surfaces. The process enables us to generate a new solution of the B–I equation from a given complex solution of a special type (which are abundant). We illustrate this with many examples. We find that the action or the energy of this family of solitons remains invariant in this family and find that the well-known Lorentz symmetry of the B–I equations is responsible for it.

  8. Non minimally coupled condensate cosmologies: a phase space analysis

    CERN Document Server

    Carloni, Sante; Cianci, Roberto

    2014-01-01

    We present an analysis of the phase space of cosmological models based on a non minimal coupling between the geometry and a fermionic condensate. We obtain that the strong constraint coming from the Dirac equations allows a detailed design of the cosmology of these models and at the same time guarantees an evolution towards a state indistinguishable from General Relativistic cosmological models. In this light, we show how the use of some specific potentials is able to reproduce naturally two de Sitter phases separated by a power law expansion which could be an interesting model for the unification of an inflationary phase and a dark energy era.

  9. Top-Flavoured Dark Matter in Dark Minimal Flavour Violation

    OpenAIRE

    Blanke, Monika; Kast, Simon

    2017-01-01

    We study a simplified model of top-flavoured dark matter in the framework of Dark Minimal Flavour Violation. In this setup the coupling of the dark matter flavour triplet to up-type quarks constitutes the only new source of flavour and CP violation. The parameter space of the model is restricted by LHC searches with missing energy final states, by neutral $D$ meson mixing data, by the observed dark matter relic abundance, and by the absence of signal in direct detection experiments. We consid...

  10. The minimal linear sigma model for the Goldstone Higgs

    CERN Document Server

    Feruglio, Ferruccio; Kanshin, Kirill; Machado, Pedro Accioly Nogueira; Rigolin, Stefano; Saa, Sara

    2016-01-01

    In the context of the minimal SO(5) linear {\\sigma}-model, a complete renormalizable Lagrangian -including gauge bosons and fermions- is considered, with the symmetry softly broken to SO(4). The scalar sector describes both the electroweak Higgs doublet and the singlet {\\sigma}. Varying the {\\sigma} mass would allow to sweep from the regime of perturbative ultraviolet completion to the non-linear one assumed in models in which the Higgs particle is a low-energy remnant of some strong dynamics. We analyze the phenomenological implications and constraints from precision observables and LHC data. Furthermore, we derive the d <= 6 effective Lagrangian in the limit of heavy exotic fermions.

  11. Minimally invasive procedures on the lumbar spine

    Science.gov (United States)

    Skovrlj, Branko; Gilligan, Jeffrey; Cutler, Holt S; Qureshi, Sheeraz A

    2015-01-01

    Degenerative disease of the lumbar spine is a common and increasingly prevalent condition that is often implicated as the primary reason for chronic low back pain and the leading cause of disability in the western world. Surgical management of lumbar degenerative disease has historically been approached by way of open surgical procedures aimed at decompressing and/or stabilizing the lumbar spine. Advances in technology and surgical instrumentation have led to minimally invasive surgical techniques being developed and increasingly used in the treatment of lumbar degenerative disease. Compared to the traditional open spine surgery, minimally invasive techniques require smaller incisions and decrease approach-related morbidity by avoiding muscle crush injury by self-retaining retractors, preventing the disruption of tendon attachment sites of important muscles at the spinous processes, using known anatomic neurovascular and muscle planes, and minimizing collateral soft-tissue injury by limiting the width of the surgical corridor. The theoretical benefits of minimally invasive surgery over traditional open surgery include reduced blood loss, decreased postoperative pain and narcotics use, shorter hospital length of stay, faster recover and quicker return to work and normal activity. This paper describes the different minimally invasive techniques that are currently available for the treatment of degenerative disease of the lumbar spine. PMID:25610845

  12. Blackfolds, plane waves and minimal surfaces

    Science.gov (United States)

    Armas, Jay; Blau, Matthias

    2015-07-01

    Minimal surfaces in Euclidean space provide examples of possible non-compact horizon geometries and topologies in asymptotically flat space-time. On the other hand, the existence of limiting surfaces in the space-time provides a simple mechanism for making these configurations compact. Limiting surfaces appear naturally in a given space-time by making minimal surfaces rotate but they are also inherent to plane wave or de Sitter space-times in which case minimal surfaces can be static and compact. We use the blackfold approach in order to scan for possible black hole horizon geometries and topologies in asymptotically flat, plane wave and de Sitter space-times. In the process we uncover several new configurations, such as black helicoids and catenoids, some of which have an asymptotically flat counterpart. In particular, we find that the ultraspinning regime of singly-spinning Myers-Perry black holes, described in terms of the simplest minimal surface (the plane), can be obtained as a limit of a black helicoid, suggesting that these two families of black holes are connected. We also show that minimal surfaces embedded in spheres rather than Euclidean space can be used to construct static compact horizons in asymptotically de Sitter space-times.

  13. Energy Management Plan.

    Science.gov (United States)

    Tasmania Dept. of Education, Hobart (Australia). Facilities Services Section.

    This report presents an overview of the energy management plan for Tasmanian schools designed to minimize the costs of all forms of energy usage within these facilities. The policy and objectives of the plan are provided along with details of the plan itself and its current status. Appendices contain an extract from Asset Management Plan for Real…

  14. Emittance minimization at the ELBE superconducting electron gun

    Energy Technology Data Exchange (ETDEWEB)

    Moeller, K.; Arnold, A.; Lu, P.; Murcek, P.; Teichert, J.; Vennekate, H.; Xiang, R.

    2014-07-01

    The transverse emittance is one of the most important quantities which characterize the quality of an electron source. For high quality experiments low beam emittance is required. By means of theoretical considerations and simulation calculations we have studied how the emittance of the Rossendorf superconducting radio-frequency photoelectron source (SRF gun) can be minimized. It turned out that neither a solenoid magnet nor the effect of space charge forces is needed to create a pronounced emittance minimum. The minimum appears by just adjusting the starting phase of the electron bunch with respect to the RF phase of the gun in a suitable way. Investigation of various correlations between the properties of the beam particles led to an explanation on how the minimum comes about. It is shown that the basic mechanism of minimization is the fact that the longitudinal properties of the particles (energy) are strongly influenced by the starting phase. Due to the coupling of the longitudinal and transverse degrees of freedom by the relativistic equation of motion the transverse degrees of freedom and thereby the emittance can be strongly influenced by the starting phase as well. The results obtained in this study will be applied to minimize the emittance in the commissioning phase of the SRF gun.

  15. Food waste minimization from a life-cycle perspective.

    Science.gov (United States)

    Bernstad Saraiva Schott, A; Andersson, T

    2015-01-01

    This article investigates potentials and environmental impacts related to household food waste minimization, based on a case study in Southern Sweden. In the study, the amount of avoidable and unavoidable food waste currently being disposed of by households was assessed through waste composition analyses and the different types of avoidable food waste were classified. Currently, both avoidable and unavoidable food waste is either incinerated or treated through anaerobic digestion. A hypothetical scenario with no generation of avoidable food waste and either anaerobic digestion or incineration of unavoidable food waste was compared to the current situation using the life-cycle assessment method, limited to analysis of global warming potential (GWP). The results from the waste composition analyses indicate that an average of 35% of household food waste is avoidable. Minimization of this waste could result in reduction of greenhouse gas emissions of 800-1400 kg/tonne of avoidable food waste. Thus, a minimization strategy would result in increased avoidance of GWP compared to the current situation. The study clearly shows that although modern alternatives for food waste treatment can result in avoidance of GWP through nutrient and energy recovery, food waste prevention yields far greater benefits for GWP compared to both incineration and anaerobic digestion.

  16. Effects of thermal fluctuations on non-minimal regular magnetic black hole

    Energy Technology Data Exchange (ETDEWEB)

    Jawad, Abdul [COMSATS Institute of Information Technology, Department of Mathematics, Lahore (Pakistan); Shahzad, M.U. [COMSATS Institute of Information Technology, Department of Mathematics, Lahore (Pakistan); University of Central Punjab, CAMS, UCP Business School, Lahore (Pakistan)

    2017-05-15

    We analyze the effects of thermal fluctuations on a regular black hole (RBH) of the non-minimal Einstein-Yang-Mill theory with gauge field of magnetic Wu-Yang type and a cosmological constant. We consider the logarithmic corrected entropy in order to analyze the thermal fluctuations corresponding to non-minimal RBH thermodynamics. In this scenario, we develop various important thermodynamical quantities, such as entropy, pressure, specific heats, Gibb's free energy and Helmholtz free energy. We investigate the first law of thermodynamics in the presence of logarithmic corrected entropy and non-minimal RBH. We also discuss the stability of this RBH using various frameworks such as the γ factor (the ratio of heat capacities), phase transition, grand canonical ensemble and canonical ensemble. It is observed that the non-minimal RBH becomes globally and locally more stable if we increase the value of the cosmological constant. (orig.)

  17. Multiple objectives application approach to waste minimization

    Institute of Scientific and Technical Information of China (English)

    张清宇

    2002-01-01

    Besides economics and controllability, waste minimization has now become an obje ctive in designing chemical processes, and usually leads to high costs of invest ment and operation. An attempt was made to minimize waste discharged from chemic al reaction processes during the design and modification process while the opera tion conditions were also optimized to meet the requirements of technology and e conomics. Multiobjectives decision nonlinear programming (NLP) was employed to o ptimize the operation conditions of a chemical reaction process and reduce waste . A modeling language package-SPEEDUP was used to simulate the process. This p aper presents a case study of the benzene production process. The flowsheet factors affecting the economics and waste generation were examined. Constraints were imposed to reduce the number of objectives and carry out optimal calculations e asily. After comparisons of all possible solutions, best-compromise approach wa s applied to meet technological requirements and minimize waste.

  18. Minimal perceptrons for memorizing complex patterns

    Science.gov (United States)

    Pastor, Marissa; Song, Juyong; Hoang, Danh-Tai; Jo, Junghyo

    2016-11-01

    Feedforward neural networks have been investigated to understand learning and memory, as well as applied to numerous practical problems in pattern classification. It is a rule of thumb that more complex tasks require larger networks. However, the design of optimal network architectures for specific tasks is still an unsolved fundamental problem. In this study, we consider three-layered neural networks for memorizing binary patterns. We developed a new complexity measure of binary patterns, and estimated the minimal network size for memorizing them as a function of their complexity. We formulated the minimal network size for regular, random, and complex patterns. In particular, the minimal size for complex patterns, which are neither ordered nor disordered, was predicted by measuring their Hamming distances from known ordered patterns. Our predictions agree with simulations based on the back-propagation algorithm.

  19. Responsiveness and minimal clinically important change

    DEFF Research Database (Denmark)

    Christiansen, David Høyrup; Frost, Poul; Falla, Deborah

    2015-01-01

    Study Design A prospective cohort study nested in a randomized controlled trial. Objectives To determine and compare responsiveness and minimal clinically important change of the modified Constant score (CS) and the Oxford Shoulder Score (OSS). Background The OSS and the CS are commonly used...... to assess shoulder outcomes. However, few studies have evaluated the measurement properties of the OSS and CS in terms of responsiveness and minimal clinically important change. Methods The study included 126 patients who reported having difficulty returning to usual activities 8 to 12 weeks after...... were observed for the CS and the OSS. Minimal clinically important change ROC values were 6 points for the OSS and 11 points for the CS, with upper 95% cutoff limits of 12 and 22 points, respectively. Conclusion The CS and the OSS were both suitable for assessing improvement after decompression surgery....

  20. Best practices for minimally invasive procedures.

    Science.gov (United States)

    Ulmer, Brenda C

    2010-05-01

    Techniques and instrumentation for minimally invasive surgical procedures originated in gynecologic surgery, but the benefits of surgery with small incisions or no incisions at all have prompted the expansion of these techniques into numerous specialties. Technologies such as robotic assistance, single-incision laparoscopic surgery, natural orifice transluminal endoscopic surgery, and video-assisted thoracoscopic surgery have led to the continued expansion of minimally invasive surgery into new specialties. With this expansion, perioperative nurses and other members of the surgical team are required to continue to learn about new technology and instrumentation, as well as the techniques and challenges involved in using new technology, to help ensure the safety of their patients. This article explores the development of minimally invasive procedures and offers suggestions for increasing patient safety.

  1. Multiple objectives application approach to waste minimization

    Institute of Scientific and Technical Information of China (English)

    张清宇

    2002-01-01

    Besides econormics and controllability, waste minimization has now become an objective in designing chemical processes,and usually leads to high costs of investment and operation.An attempt was mede to minimize waste discharged from chemical reaction processes during the design and modification process while the operation conditions were also optimized to meet the requirements of technology and economics.Multiob-jectives decision nonlinear programming(NLP) was emplyed optimize the operation conditions of a chemical reaction process and reduce waste. A modeling package-SPEEDUP was used to simulate the process.This paper presents a case study of the benzenc production process.The flowsheer factors affecting the economics and waste generation were examined.Constraints were imposed to reduce the number of objectives and carry out optimal calculations easily.After comparisons of all possiblle solutions,best-compromise approach was applied to meet technological requirements and minimize waste.

  2. Minimal flavour violation and anomalous top decays

    Energy Technology Data Exchange (ETDEWEB)

    Faller, Sven; Mannel, Thomas [Theoretische Physik 1, Department Physik, Universitaet Siegen, D-57068 Siegen (Germany); Gadatsch, Stefan [Nikhef, National Institute for Subatomatic Physics, P.O. Box 41882, 1009 Amsterdam (Netherlands)

    2013-07-01

    Any experimental evidence of anomalous top-quark couplings will open a window to study physics beyond the standard model (SM). However, all current flavour data indicate that nature is close to ''minimal flavour violation'', i.e. the pattern of flavour violation is given by the CKM matrix, including the hierarchy of parameters. In this talk we present results of the conceptual test of minimal flavour violation for the anomalous charged as well as flavour changing top-quark couplings. Our analysis is embedded in two-Higgs doublet model of type II (2HDM-II). Including renormalization effects, we calculate the top decay rates taking into account anomalous couplings constrained by minimal flavour violation.

  3. Minimal Length Scale Scenarios for Quantum Gravity

    Directory of Open Access Journals (Sweden)

    Sabine Hossenfelder

    2013-01-01

    Full Text Available We review the question of whether the fundamental laws of nature limit our ability to probe arbitrarily short distances. First, we examine what insights can be gained from thought experiments for probes of shortest distances, and summarize what can be learned from different approaches to a theory of quantum gravity. Then we discuss some models that have been developed to implement a minimal length scale in quantum mechanics and quantum field theory. These models have entered the literature as the generalized uncertainty principle or the modified dispersion relation, and have allowed the study of the effects of a minimal length scale in quantum mechanics, quantum electrodynamics, thermodynamics, black-hole physics and cosmology. Finally, we touch upon the question of ways to circumvent the manifestation of a minimal length scale in short-distance physics.

  4. Minimal Length Scale Scenarios for Quantum Gravity.

    Science.gov (United States)

    Hossenfelder, Sabine

    2013-01-01

    We review the question of whether the fundamental laws of nature limit our ability to probe arbitrarily short distances. First, we examine what insights can be gained from thought experiments for probes of shortest distances, and summarize what can be learned from different approaches to a theory of quantum gravity. Then we discuss some models that have been developed to implement a minimal length scale in quantum mechanics and quantum field theory. These models have entered the literature as the generalized uncertainty principle or the modified dispersion relation, and have allowed the study of the effects of a minimal length scale in quantum mechanics, quantum electrodynamics, thermodynamics, black-hole physics and cosmology. Finally, we touch upon the question of ways to circumvent the manifestation of a minimal length scale in short-distance physics.

  5. Cogging Torque Minimization in Transverse Flux Machines

    Energy Technology Data Exchange (ETDEWEB)

    Husain, Tausif; Hasan, Iftekhar; Sozer, Yilmaz; Husain, Iqbal; Muljadi, Eduard

    2017-02-16

    This paper presents the design considerations in cogging torque minimization in two types of transverse flux machines. The machines have a double stator-single rotor configuration with flux concentrating ferrite magnets. One of the machines has pole windings across each leg of an E-Core stator. Another machine has quasi-U-shaped stator cores and a ring winding. The flux in the stator back iron is transverse in both machines. Different methods of cogging torque minimization are investigated. Key methods of cogging torque minimization are identified and used as design variables for optimization using a design of experiments (DOE) based on the Taguchi method. A three-level DOE is performed to reach an optimum solution with minimum simulations. Finite element analysis is used to study the different effects. Two prototypes are being fabricated for experimental verification.

  6. Minimally invasive surgical techniques in periodontal regeneration.

    Science.gov (United States)

    Cortellini, Pierpaolo

    2012-09-01

    A review of the current scientific literature was undertaken to evaluate the efficacy of minimally invasive periodontal regenerative surgery in the treatment of periodontal defects. The impact on clinical outcomes, surgical chair-time, side effects and patient morbidity were evaluated. An electronic search of PUBMED database from January 1987 to December 2011 was undertaken on dental journals using the key-word "minimally invasive surgery". Cohort studies, retrospective studies and randomized controlled clinical trials referring to treatment of periodontal defects with at least 6 months of follow-up were selected. Quality assessment of the selected studies was done through the Strength of Recommendation Taxonomy Grading (SORT) System. Ten studies (1 retrospective, 5 cohorts and 4 RCTs) were included. All the studies consistently support the efficacy of minimally invasive surgery in the treatment of periodontal defects in terms of clinical attachment level gain, probing pocket depth reduction and minimal gingival recession. Six studies reporting on side effects and patient morbidity consistently indicate very low levels of pain and discomfort during and after surgery resulting in a reduced intake of pain-killers and very limited interference with daily activities in the post-operative period. Minimally invasive surgery might be considered a true reality in the field of periodontal regeneration. The observed clinical improvements are consistently associated with very limited morbidity to the patient during the surgical procedure as well as in the post-operative period. Minimally invasive surgery, however, cannot be applied at all cases. A stepwise decisional algorithm should support clinicians in choosing the treatment approach.

  7. Review of Minimal Flavor Constraints for Technicolor

    DEFF Research Database (Denmark)

    S. Fukano, Hidenori; Sannino, Francesco

    2010-01-01

    We analyze the constraints on the the vacuum polarization of the standard model gauge bosons from a minimal set of flavor observables valid for a general class of models of dynamical electroweak symmetry breaking. We will show that the constraints have a strong impact on the self-coupling and mas......We analyze the constraints on the the vacuum polarization of the standard model gauge bosons from a minimal set of flavor observables valid for a general class of models of dynamical electroweak symmetry breaking. We will show that the constraints have a strong impact on the self...

  8. A New Minimal Rough Set Axiom Group

    Institute of Scientific and Technical Information of China (English)

    DAI Jian-hua

    2004-01-01

    Rough set axiomatization is one aspect of rough set study, and the purpose is to characterize rough set theory using independable and minimal axiom groups. Thus, rough set theory can be studied by logic and axiom system methods. To characterize rough set theory, an axiom group named H consisting of 4 axioms, is proposed. That validity of the axiom group in characterizing rough set theory is reasonable, is proved. Simultaneously, the minimization of the axiom group, which requires that each axiom is an inequality and each is independent, is proved. The axiom group is helpful for researching rough set theory by logic and axiom system methods.

  9. On Time with Minimal Expected Cost!

    DEFF Research Database (Denmark)

    David, Alexandre; Jensen, Peter Gjøl; Larsen, Kim Guldstrand

    2014-01-01

    ) timed game essentially defines an infinite-state Markov (reward) decision proces. In this setting the objective is classically to find a strategy that will minimize the expected reachability cost, but with no guarantees on worst-case behaviour. In this paper, we provide efficient methods for computing...... reachability strategies that will both ensure worst case time-bounds as well as provide (near-) minimal expected cost. Our method extends the synthesis algorithms of the synthesis tool Uppaal-Tiga with suitable adapted reinforcement learning techniques, that exhibits several orders of magnitude improvements w...

  10. Minimal String Theory and the Douglas Equation

    Science.gov (United States)

    Belavin, A. A.; Belavin, V. A.

    We use the connection between the Frobenius manifold and the Douglas string equation to further investigate Minimal Liouville gravity. We search for a solution of the Douglas string equation and simultaneously a proper transformation from the KdV to the Liouville frame which ensures the fulfilment of the conformal and fusion selection rules. We find that the desired solution of the string equation has an explicit and simple form in the flat coordinates on the Frobenius manifold in the general case of (p,q) Minimal Liouville gravity.

  11. The concept of minimally invasive dentistry.

    Science.gov (United States)

    Ericson, Dan

    2007-01-01

    This paper reviews Minimally Invasive Dentistry (MID) from a day-to-day dentistry perspective, focusing mostly on cariology and restorative dentistry, even though it embraces many aspects of dentistry. The concept of MID supports a systematic respect for the original tissue, including diagnosis, risk assessment, preventive treatment, and minimal tissue removal upon restoration. The motivation for MID emerges from the fact that fillings are not permanent and that the main reasons for failure are secondary caries and filling fracture. To address these flaws, there is a need for economical re-routing so that practices can survive on maintaining dental health and not only by operative procedures.

  12. Minimally invasive restorative dentistry: a biomimetic approach.

    Science.gov (United States)

    Malterud, Mark I

    2006-08-01

    When providing dental treatment for a given patient, the practitioner should use a minimally invasive technique that conserves sound tooth structure as a clinical imperative. Biomimetics is a tenet that guides the author's practice and is generally described as the mimicking of natural life. This can be accomplished in many cases using contemporary composite resins and adhesive dental procedures. Both provide clinical benefits and support the biomimetic philosophy for treatment. This article illustrates a minimally invasive approach for the restoration of carious cervical defects created by poor hygiene exacerbated by the presence of orthodontic brackets.

  13. Minimal Superstrings and Loop Gas Models

    CERN Document Server

    Gaiotto, D; Takayanagi, T; Gaiotto, Davide; Rastelli, Leonardo; Takayanagi, Tadashi

    2005-01-01

    We reformulate the matrix models of minimal superstrings as loop gas models on random surfaces. In the continuum limit, this leads to the identification of minimal superstrings with certain bosonic string theories, to all orders in the genus expansion. RR vertex operators arise as operators in a Z_2 twisted sector of the matter CFT. We show how the loop gas model implements the sum over spin structures expected from the continuum RNS formulation. Open string boundary conditions are also more transparent in this language.

  14. Linearized non-minimal higher curvature supergravity

    Directory of Open Access Journals (Sweden)

    Fotis Farakos

    2015-05-01

    Full Text Available In the framework of linearized non-minimal supergravity (20/20, we present the embedding of the R+R2 model and we analyze its field spectrum. As usual, the auxiliary fields of the Einstein theory now become propagating, giving rise to additional degrees of freedom, which organize themselves into on-shell irreducible supermultiplets. By performing the analysis both in component and superspace formulations we identify the new supermultiplets. On top of the two massive chiral superfields reminiscent of the old-minimal supergravity embedding, the spectrum contains also a consistent physical, massive, vector supermultiplet and a tachyonic ghost, massive, vector supermultiplet.

  15. Linearized non-minimal higher curvature supergravity

    Science.gov (United States)

    Farakos, Fotis; Kehagias, Alex; Koutrolikos, Konstantinos

    2015-05-01

    In the framework of linearized non-minimal supergravity (20/20), we present the embedding of the R +R2 model and we analyze its field spectrum. As usual, the auxiliary fields of the Einstein theory now become propagating, giving rise to additional degrees of freedom, which organize themselves into on-shell irreducible supermultiplets. By performing the analysis both in component and superspace formulations we identify the new supermultiplets. On top of the two massive chiral superfields reminiscent of the old-minimal supergravity embedding, the spectrum contains also a consistent physical, massive, vector supermultiplet and a tachyonic ghost, massive, vector supermultiplet.

  16. Linearized Non-Minimal Higher Curvature Supergravity

    CERN Document Server

    Farakos, Fotis; Koutrolikos, Konstantinos

    2015-01-01

    In the framework of linearized non-minimal supergravity (20/20), we present the embedding of the $R + R^2$ model and we analyze its field spectrum. As usual, the auxiliary fields of the Einstein theory now become propagating, giving rise to additional degrees of freedom, which organize themselves into on-shell irreducible supermultiplets. By performing the analysis both in component and superspace formulations we identify the new supermultiplets. On top of the two massive chiral superfields reminiscent of the old-minimal supergravity embedding, the spectrum contains also a consistent physical, massive, vector supermultiplet and a tachyonic ghost, massive, vector supermultiplet.

  17. MINIMAL IMMERSIONS OF SPHERES INTO SPHERES

    Science.gov (United States)

    Do Carmo, Manfredo P.; Wallach, Nolan R.

    1969-01-01

    In this paper we announce a qualitative description of an important class of closed n-dimensional submanifolds of the m-dimensional sphere, namely, those which locally minimize the n-area in the same way that geodesics minimize the arc length and are themselves locally n-spheres of constant radius r; those r that may appear are called admissible. It is known that for n = 2 each admissible r determines a unique element of the above class. The main result here is that for each n ≥ 3 and each admissible r ≥ [unk]8 there exists a continuum of distinct such submanifolds. PMID:16591771

  18. Minimization and error estimates for a class of the nonlinear Schrodinger eigenvalue problems

    Institute of Scientific and Technical Information of China (English)

    MurongJIANG; JiachangSUN

    2000-01-01

    It is shown that the nonlinear eigenvaiue problem can be transformed into a constrained functional problem. The corresponding minimal function is a weak solution of this nonlinear problem. In this paper, one type of the energy functional for a class of the nonlinear SchrSdinger eigenvalue problems is proposed, the existence of the minimizing solution is proved and the error estimate is given out.

  19. Minimal flavour violation in the quark and lepton sector and beyond

    Energy Technology Data Exchange (ETDEWEB)

    Uhlig, S.L.

    2008-01-07

    We address to explain the matter-antimatter asymmetry of the universe in a framework that generalizes the quark minimal flavour violation hypothesis to the lepton sector. We study the impact of CP violation present at low and high energies and investigate the existence of correlations among leptogenesis and lepton flavour violation. Further we present an approach alternative to minimal flavour violation where the suppression of flavour changing transitions involving quarks and leptons is governed by hierarchical fermion wave functions. (orig.)

  20. Alternative solution of the gamma-rigid Bohr Hamiltonian in minimal length formalism

    Science.gov (United States)

    Alimohammadi, M.; Hassanabadi, H.

    2017-01-01

    The Bohr-Mottelson Hamiltonian on γ-rigid regime has been extended to the minimal length formalism for the infinite square well potential and the corresponding wave functions as well as the spectra are obtained. The effect of minimal length on energy spectra is studied via various figures and tables and numerical calculations are included for some nuclei and the results are compared with other results and existing experimental data.