A split SUSY model from SUSY GUT
Wang, FeiDepartment of Physics and Engineering, Zhengzhou University, Zhengzhou, 450000, P.R. China; Wang, Wenyu(Institute of Theoretical Physics, College of Applied Science, Beijing University of Technology, Beijing, 100124, P.R. China); Yang, Jin(State Key Laboratory of Theoretical Physics, Institute of Theoretical Physics, Chinese Academy of Sciences, Beijing, 100190, P.R. China)
2015-01-01
We propose to split the sparticle spectrum from the hierarchy between the GUT scale and the Planck scale. A split supersymmetric model, which gives non-universal gaugino masses, is built with proper high dimensional operators in the framework of SO(10) GUT. Based on a calculation of two-loop beta functions for gauge couplings (taking into account all weak scale threshold corrections), we check the gauge coupling unification and dark matter constraints (relic density and direct detections). We...
Energy Technology Data Exchange (ETDEWEB)
Kuroki, Tsunehide, E-mail: kuroki@dg.kagawa-nct.ac.jp [General Eduction, National Institute of Technology, Kagawa College, 551 Kohda, Takuma-cho, Mitoyo, Kagawa 769-1192 (Japan); Sugino, Fumihiko, E-mail: fusugino@gmail.com [Okayama Institute for Quantum Physics, Furugyocho 1-7-36, Naka-ku, Okayama 703-8278 (Japan)
2017-06-15
In the previous paper, the authors pointed out correspondence between a supersymmetric double-well matrix model and two-dimensional type IIA superstring theory on a Ramond–Ramond background from the viewpoint of symmetry and spectrum. This was confirmed by agreement between planar correlation functions in the matrix model and tree-level amplitudes in the superstring theory. In order to investigate the correspondence further, in this paper we compute correlation functions to all order of genus expansion in the double scaling limit of the matrix model. One-point functions of operators protected by supersymmetry terminate at some finite order, whereas those of unprotected operators yield non-Borel summable series. The behavior of the latter is characteristic in string perturbation series, providing further evidence that the matrix model describes a string theory. Moreover, instanton corrections to the planar one-point functions are also computed, and universal logarithmic scaling behavior is found for non-supersymmetric operators.
Directory of Open Access Journals (Sweden)
Tsunehide Kuroki
2017-06-01
Full Text Available In the previous paper, the authors pointed out correspondence between a supersymmetric double-well matrix model and two-dimensional type IIA superstring theory on a Ramond–Ramond background from the viewpoint of symmetry and spectrum. This was confirmed by agreement between planar correlation functions in the matrix model and tree-level amplitudes in the superstring theory. In order to investigate the correspondence further, in this paper we compute correlation functions to all order of genus expansion in the double scaling limit of the matrix model. One-point functions of operators protected by supersymmetry terminate at some finite order, whereas those of unprotected operators yield non-Borel summable series. The behavior of the latter is characteristic in string perturbation series, providing further evidence that the matrix model describes a string theory. Moreover, instanton corrections to the planar one-point functions are also computed, and universal logarithmic scaling behavior is found for non-supersymmetric operators.
Neutrino masses from SUSY breaking in radiative seesaw models
Energy Technology Data Exchange (ETDEWEB)
Figueiredo, Antonio J.R. [University of Lisbon, Centro de Fisica Teorica de Particulas (CFTP), Instituto Superior Tecnico, Lisbon (Portugal)
2015-03-01
Radiatively generated neutrino masses (m{sub ν}) are proportional to supersymmetry (SUSY) breaking, as a result of the SUSY non-renormalisation theorem. In this work, we investigate the space of SUSY radiative seesaw models with regard to their dependence on SUSY breaking (SUSY). In addition to contributions from sources of SUSY that are involved in electroweak symmetry breaking (SUSY{sub EWSB} contributions), and which are manifest from left angle F{sub H}{sup †} right angle = μ left angle anti H right angle ≠ 0 and left angle D right angle = g sum {sub H} left angle H{sup †} x {sub H} H right angle ≠ 0, radiatively generated m{sub ν} can also receive contributions from SUSY sources that are unrelated to EWSB (SUSY{sub EWS} contributions). We point out that recent literature overlooks pure-SUSY{sub EWSB} contributions (∝ μ/M) that can arise at the same order of perturbation theory as the leading order contribution from SUSY{sub EWS}. We show that there exist realistic radiative seesaw models in which the leading order contribution to m{sub ν} is proportional to SUSY{sub EWS}. To our knowledge no model with such a feature exists in the literature. We give a complete description of the simplest model topologies and their leading dependence on SUSY. We show that in one-loop realisations LLHH operators are suppressed by at least μ m{sub soft}/M{sup 3} or m{sub soft}{sup 2}/M{sup 3}. We construct a model example based on a oneloop type-II seesaw. An interesting aspect of these models lies in the fact that the scale of soft-SUSY effects generating the leading order m{sub ν} can be quite small without conflicting with lower limits on the mass of new particles. (orig.)
Hilltop supernatural inflation and SUSY unified models
Energy Technology Data Exchange (ETDEWEB)
Kohri, Kazunori [Cosmophysics Group, Theory Center, IPNS KEK, and The Graduate University for Advanced Studies (Sokendai), 1-1 Oho, Tsukuba, 305-0801 (Japan); Lim, C.S. [Department of Mathematics, Tokyo Woman' s Christian University, Tokyo, 167-8585 (Japan); Lin, Chia-Min [Department of Physics, Chuo University, Bunkyo-ku, Tokyo, 112 (Japan); Mimura, Yukihiro, E-mail: kohri@post.kek.jp, E-mail: lim@lab.twcu.ac.jp, E-mail: lin@chuo-u.ac.jp, E-mail: mimura@hep1.phys.ntu.edu.tw [Department of Physics, National Taiwan University, Taipei, 10617 Taiwan (China)
2014-01-01
In this paper, we consider high scale (100TeV) supersymmetry (SUSY) breaking and realize the idea of hilltop supernatural inflation in concrete particle physics models based on flipped-SU(5)and Pati-Salam models in the framework of supersymmetric grand unified theories (SUSY GUTs). The inflaton can be a flat direction including right-handed sneutrino and the waterfall field is a GUT Higgs. The spectral index is n{sub s} = 0.96 which fits very well with recent data by PLANCK satellite. There is no both thermal and non-thermal gravitino problems. Non-thermal leptogenesis can be resulted from the decay of right-handed sneutrino which plays (part of) the role of inflaton.
Hilltop supernatural inflation and SUSY unified models
Kohri, Kazunori; Lim, C. S.; Lin, Chia-Min; Mimura, Yukihiro
2014-01-01
In this paper, we consider high scale (100TeV) supersymmetry (SUSY) breaking and realize the idea of hilltop supernatural inflation in concrete particle physics models based on flipped-SU(5)and Pati-Salam models in the framework of supersymmetric grand unified theories (SUSY GUTs). The inflaton can be a flat direction including right-handed sneutrino and the waterfall field is a GUT Higgs. The spectral index is ns = 0.96 which fits very well with recent data by PLANCK satellite. There is no both thermal and non-thermal gravitino problems. Non-thermal leptogenesis can be resulted from the decay of right-handed sneutrino which plays (part of) the role of inflaton.
Darkenergy andneutrino model in SUSY
Takahashi, Ryo
2007-01-01
We consider a Mass Varying Neutrinos (MaVaNs) model in supersymmetric theory. The model includes effects of supersymmetry breaking transmitted by the gravitational interaction from the hidden sector, in which supersymmetry was broken, to the dark energy sector. Then evolutions of the neutrino mass and the equation of state parameter of the dark energy are presented in the model. It is remarked that only the mass of a sterile neutrino is variable in the case of the vanishing mixing between the left-handed and a sterile neutrino on cosmological time scale. The finite mixing makes the mass of the left-handed neutrino variable.
Phenomenology of the minimal $ SO (10) $ SUSY model
Indian Academy of Sciences (India)
In this talk I define what I call the minimal S O ( 10 ) SUSY model. I then discuss the phenomenological consequences of this theory, vis-a-vis gauge and Yukawa coupling unification, Higgs and super-particle masses, the anomalous magnetic moment of the muon, the decay B s → + − and dark matter.
Lepton Flavor Violation in Predictive SUSY-GUT Models
Energy Technology Data Exchange (ETDEWEB)
Albright, Carl H.; /Northern Illinois U. /Fermilab; Chen, Mu-Chun; /UC, Irvine
2008-02-01
There have been many theoretical models constructed which aim to explain the neutrino masses and mixing patterns. While many of the models will be eliminated once more accurate determinations of the mixing parameters, especially sin{sup 2} 2{theta}{sub 13}, are obtained, charged lepton flavor violation (LFV) experiments are able to differentiate even further among the models. In this paper, they investigate various rare LFV processes, such as {ell}{sub i} {yields} {ell}{sub j} + {gamma} and {mu} - e conversion, in five predictive SUSY SO(10) models and their allowed soft SUSY breaking parameter space in the constrained minimal SUSY standard model (CMSSM). Utilizing the WMAP dark matter constraints, they obtain lower bounds on the branching ratios of these rare processes and find that at least three of the five models they consider give rise to predictions for {mu} {yields} e + {gamma} that will be tested by the MEG collaboration at PSI. in addition, the next generation {mu} - e conversion experiment has sensitivity to the predictions of all five models, making it an even more robust way to test these models. While generic studies have emphasized the dependence of the branching ratios of these rare processes on the reactor neutrino angle, {theta}{sub 13}, and the mass of the heaviest right-handed neutrino, M{sub 3}, they find very massive M{sub 3} is more significant than large {theta}{sub 13} in leading to branching ratios near to the present upper limits.
Low-Energy Predictions of SUSY GUT’S: the Minimal Model Versus the Finite Model
Kazakov, D. I.; Kondrashuk, I. N.
We consider the low-energy predictions for sin2 θW and τproton of SUSY GUT’s along the lines of Ref. 1. Special attention is paid to the dependence on the mass spectrum of superpartners and possible heavy inhabitants of the Great desert. The minimal and finite SUSY SU(5) models with light and heavy t squark and additional higgsino are considered. It is shown that modern precise LEP data are naturally reproduced within the finite SUSY SU(5) GUT with both light and heavy t squark and light higgsino with a reasonable SU(5) splitting.
The Reach of the Fermilab Tevatron and CERN LHC for Gaugino Mediated SUSY Breaking Models
Baer, Howard W; Krupovnickas, T; Tata, Xerxes; Baer, Howard; Belyaev, Alexander; Krupovnickas, Tadas; Tata, Xerxes
2002-01-01
In supersymmetric models with gaugino mediated SUSY breaking (inoMSB), it is assumed that SUSY breaking on a hidden brane is communicated to the visible brane via gauge superfields which propagate in the bulk. This leads to GUT models where the common gaugino mass $m_{1/2}$ is the only soft SUSY breaking term to receive contributions at tree level. To obtain a viable phenomenology, it is assumed that the gaugino mass is induced at some scale $M_c$ beyond the GUT scale, and that additional renormalization group running takes place between $M_c$ and $M_{GUT}$ as in a SUSY GUT. We assume an SU(5) SUSY GUT above the GUT scale, and compute the SUSY particle spectrum expected in models with inoMSB. We use the Monte Carlo program ISAJET to simulate signals within the inoMSB model, and compute the SUSY reach including cuts and triggers approriate to Fermilab Tevatron and CERN LHC experiments. We find no reach for SUSY by the Tevatron collider in the trilepton channel. %either with or without %identified tau leptons. ...
Reach of the Fermilab Tevatron and CERN LHC for gaugino mediated SUSY breaking models
Baer, Howard W; Krupovnickas, T; Tata, Xerxes; 10.1103/PhysRevD.65.075024
2002-01-01
In supersymmetric models with gaugino mediated SUSY breaking (gMSB), it is assumed that SUSY breaking on a hidden brane is communicated to the visible brane via gauge superfields which propagate in the bulk. This leads to GUT models where the common gaugino mass m/sub 1/2/ is the only soft SUSY breaking term to receive contributions at the tree level. To obtain a viable phenomenology, it is assumed that the gaugino mass is induced at some scale M/sub c/ beyond the GUT scale, and that additional renormalization group running takes place between M/sub c/ and M/sub GUT/ as in a SUSY GUT. We assume an SU(5) SUSY GUT above the GUT scale, and compute the SUSY particle spectrum expected in models with gMSB. We use the Monte Carlo program ISAJET to simulate signals within the gMSB model, and compute the SUSY reach including cuts and triggers appropriate to Fermilab Tevatron and CERN LHC experiments. We find no reach for SUSY by the Tevatron collider in the trilepton channel. At the CERN LHC, values of m/sub 1/2/=1000...
The ATLAS discovery reach for SUSY models with early data
Dietrich, Janet
2010-01-01
The search for physics beyond the Standard Model (BSM) is one of the most important goals for the general purpose detector ATLAS at the Large Hadron Collider at CERN. We review some of the current strategies to search for generic SUSY models with R-parity conservation in channels with jets, leptons and missing transverse energy for an integrated luminosity of L = 200 pb^-1 at a centre-of-mass energy s = $10TeV. Only a selection of the results is presented with a focus on the discovery potential for inclusive searches. The discovery reach for a centre-of-mass energy of s = 7TeV and an integrated luminosity of L = 1 fb^-1 is expected to be very similar to the one discussed in this note.
Antonella Del Rosso
2012-01-01
Recent information from the LHC experiments, the relatively low mass of the new boson and other data coming from experiments looking for dark matter worldwide are placing new constraints on the existence of supersymmetry (SUSY). However, there is a large community of scientists that still believes that SUSY particles are out there. Like lost keys at night, perhaps we have been looking for SUSY under the wrong lamp-posts… Can you work out this rebus? Source: Caroline Duc. So far, SUSY is “just” a theoretical physics model, which could solve problems beyond the Standard Model by accounting for dark matter and other phenomena in the Universe. However, SUSY has not been spotted so far, and might be hiding because of features different from what physicists previously expected. “Currently, there is no evidence for SUSY, but neither has any experimental data ruled it out. Many searches have focused on simplified versions of the theory but, given the recen...
Coupled Boltzmann computation of mixed axion neutralino dark matter in the SUSY DFSZ axion model
Energy Technology Data Exchange (ETDEWEB)
Bae, Kyu Jung; Baer, Howard; Serce, Hasan [Department of Physics and Astronomy, University of Oklahoma, 440 West Brooks, Norman, OK 73019 (United States); Lessa, Andre, E-mail: bae@nhn.ou.edu, E-mail: baer@nhn.ou.edu, E-mail: lessa@fma.if.usp.br, E-mail: serce@ou.edu [Instituto de Física, Universidade de São Paulo, São Paulo – SP (Brazil)
2014-10-01
The supersymmetrized DFSZ axion model is highly motivated not only because it offers solutions to both the gauge hierarchy and strong CP problems, but also because it provides a solution to the SUSY μ-problem which naturally allows for a Little Hierarchy. We compute the expected mixed axion-neutralino dark matter abundance for the SUSY DFSZ axion model in two benchmark cases—a natural SUSY model with a standard neutralino underabundance (SUA) and an mSUGRA/CMSSM model with a standard overabundance (SOA). Our computation implements coupled Boltzmann equations which track the radiation density along with neutralino, axion, axion CO (produced via coherent oscillations), saxion, saxion CO, axino and gravitino densities. In the SUSY DFSZ model, axions, axinos and saxions go through the process of freeze-in—in contrast to freeze-out or out-of-equilibrium production as in the SUSY KSVZ model—resulting in thermal yields which are largely independent of the re-heat temperature. We find the SUA case with suppressed saxion-axion couplings (ξ=0) only admits solutions for PQ breaking scale f{sub a}∼< 6× 10{sup 12} GeV where the bulk of parameter space tends to be axion-dominated. For SUA with allowed saxion-axion couplings (ξ =1), then f{sub a} values up to ∼ 10{sup 14} GeV are allowed. For the SOA case, almost all of SUSY DFSZ parameter space is disallowed by a combination of overproduction of dark matter, overproduction of dark radiation or violation of BBN constraints. An exception occurs at very large f{sub a}∼ 10{sup 15}–10{sup 16} GeV where large entropy dilution from CO-produced saxions leads to allowed models.
Low-energy predictions of SUSY GUT's; The minimal model versus the finite model
Energy Technology Data Exchange (ETDEWEB)
Kazakov, D.I.; Kondrashuk, I.N. (Lab. of Theoretical Physics, Joint Inst. for Nuclear Research, Dubna (SU))
1992-06-30
This paper considers the low-energy predictions for sin{sup 2}{theta}{sub w} and {tau}{sub proton} of SUSY GUT's. Special attention is paid to the dependence on the mass spectrum of superpartners and possible heavy inhabitants of the Great desert. The minimal and finite SUSY SU(5) models with light and heavy t squark and additional higgsino are considered. It i shown that modern precise LEP data are naturally reproduced within the finite SUSY SU(5) GUT with both light and heavy t squark and light higgsino with a reasonable SU(5) splitting.
Lepton-Flavour-Violation in SUSY Models with and without R-parity
Tobe, K
2000-01-01
We discuss Lepton-Flavour-Violating phenomena such as $\\mu \\to e \\gamma$, $\\mu \\to eee$, and $\\mu \\to e$ conversion in nuclei in SUSY models with and without R-parity. We stress that experimental searches for all the LFV processes are important to distinguish between the different models.
Naturalness, SUSY heavy higgses and flavor constraints
CERN. Geneva
2014-01-01
I will demonstrate that supersymmetric (SUSY) higgses provide an important diagnostic for electroweak naturalness in the SUSY paradigm. I first review the naturalness problem of the Standard Model (SM) and SUSY as one of its most promising solutions. I study the masses of heavy Higgses in SUSY theories under broad assumptions, and show how they are constrained by their role in Electroweak symmetry breaking. I then show how Flavor Physics severely constrains large parts of SUSY parameter space, otherwise favored by naturalness. If SUSY Higgses are not discovered at relatively low mass during the next LHC run, this tension will further increase, disfavoring naturalness from SUSY.
Katz, Andrey; Pokorski, Stefan; Redigolo, Diego; Ziegler, Robert
2017-01-31
We investigate the general structure of mirror symmetry breaking in the Twin Higgs scenario. We show, using the IR effective theory, that a significant gain in fine tuning can be achieved if the symmetry is broken hardly. We emphasize that weakly coupled UV completions can naturally accommodate this scenario. We analyze SUSY UV completions and present a simple Twin SUSY model with a tuning of around 10% and colored superpartners as heavy as 2 TeV. The collider signatures of general Twin SUSY models are discussed with a focus on the extended Higgs sectors.
Mamuzic, Judita; The ATLAS collaboration
2017-01-01
Supersymmetry (SUSY) is considered one of the best motivated extensions of the Standard Model. It postulates a fundamental symmetry between fermions and bosons, and introduces a set of new supersymmetric particles at the electroweak scale. It addresses the hierarchy and naturalness problem, gives a solution to the gauge coupling unification, and offers a cold dark matter candidate. Different aspects of SUSY searches, using strong, electroweak, third generation production, and R-parity violation and long lived particles are being studied at the LHC. An overview of most recent SUSY searches results using the 13 TeV ATLAS RUN2 data will be presented.
Fermion Masses and Mixing in SUSY Grand Unified Gauge Models with Extended Gut Gauge Groups
Energy Technology Data Exchange (ETDEWEB)
Chou, Chih-Lung
2005-04-05
The authors discuss a class of supersymmetric (SUSY) grand unified gauge (GUT) models based on the GUT symmetry G x G or G x G x G, where G denotes the GUT group that has the Standard Model symmetry (SU(3){sub c} x SU(2){sub L} x U(1){sub Y}) embedded as a subgroup. As motivated from string theory, these models are constructed without introducing any Higgs field of rani two or higher. Thus all the Higgs fields are in the fundamental representations of the extended GUT symmetry or, when G = SO(10), in the spinorial representation. These Higgs fields, when acquiring their vacuum expectation values, would break the extended GUT symmetry down to the Standard Model symmetry. In this dissertation, they argue that the features required of unified models, such as the Higgs doublet-triplet splitting, proton stability, and the hierarchy of fermion masses and mixing angles, could have natural explanations in the framework of the extended SUSY GUTs. Furthermore, they argue that the frameworks used previously to construct SO(10) GUT models using adjoint Higgs fields can naturally arise from the SO(10) x SO(10) and SO(10) x SO(10) x SO(10) models by integrating out heavy fermions. This observation thus suggests that the traditional SUSY GUT SO(10) theories can be viewed as the low energy effective theories generated by breaking the extended GUT symmetry down to the SO(10) symmetry.
Benchmark models, planes lines and points for future SUSY searches at the LHC
Energy Technology Data Exchange (ETDEWEB)
AbdusSalam, S.S. [The Abdus Salam International Centre for Theoretical Physics, Trieste (Italy); Allanach, B.C. [Cambridge Univ. (United Kingdom). Dept. of Applied Mathematics and Theoretical Physics; Dreiner, H.K. [Bonn Univ. (DE). Bethe Center for Theoretical Physics and Physikalisches Inst.] (and others)
2012-03-15
We define benchmark models for SUSY searches at the LHC, including the CMSSM, NUHM, mGMSB, mAMSB, MM-AMSB and p19MSSM, as well as models with R-parity violation and the NMSSM. Within the parameter spaces of these models, we propose benchmark subspaces, including planes, lines and points along them. The planes may be useful for presenting results of the experimental searches in different SUSY scenarios, while the specific benchmark points may serve for more detailed detector performance tests and comparisons. We also describe algorithms for defining suitable benchmark points along the proposed lines in the parameter spaces, and we define a few benchmark points motivated by recent fits to existing experimental data.
Phenomenology of the minimal ЛЗ(10) sUsY model
Indian Academy of Sciences (India)
Let me first define the minimal SO(10) sUsY model [MsOЅјsM] [1] and then I will discuss the phenomenological consequences of this theory. In the MsOЅјsM the quarks and leptons of one family are contained in a 16 dimensional spinor representation and the two Higgs doublets of the MssM come from a single 10.
SUSY: New Perspectives and Variants
Munoz, C.
2007-01-01
Although supersymmetry (SUSY) is thirty five years old, it is still one of the most attractive theories for physics beyond the standard model. Assuming that SUSY will be discovered at the LHC, the key question is: What SUSY model do we expect to be the correct one ? After reviewing briefly the advantages and problems of SUSY, several interesting models that have been proposed in the literature will be discussed. In particular, models such as the MSSM, BRpV, NMSSM, and possible extensions. We ...
Masiero, A; Vives, O
2004-01-01
After a quarter of century of intense search for new physics beyond the Standard Model (SM), two ideas stand out to naturally cope with (i) small neutrino masses and (ii) a light higgs boson : Seesaw and SUSY. The combination of these two ideas, i.e. SUSY seesaw exhibits a potentially striking signature: a strong (or even very strong) enhancement of lepton flavour violation (LFV), which on the contrary remains unobservable in the SM seesaw. Indeed, even when supersymmetry breaking is completely flavour blind, Renormalisation Group running effects are expected to generate large lepton flavour violating entries at the weak scale. In Grand Unified theories, these effects can be felt even in hadronic physics. We explicitly show that in a class of SUSY SO(10) GUTs there exist cases where LFV and CP violation in B-physics can constitute a major road in simultaneously confirming the ideas of Seesaw and low-energy SUSY.
Energy Technology Data Exchange (ETDEWEB)
Berger, C.F.; Gainer, J.S.; Hewett, J.L.; Rizzo, T.G.
2008-12-11
We begin an exploration of the physics associated with the general CP-conserving MSSM with Minimal Flavor Violation, the pMSSM. The 19 soft SUSY breaking parameters in this scenario are chosen so as to satisfy all existing experimental and theoretical constraints assuming that the WIMP is a thermal relic, i.e., the lightest neutralino. We scan this parameter space twice using both flat and log priors for the soft SUSY breaking mass parameters and compare the results which yield similar conclusions. Detailed constraints from both LEP and the Tevatron searches play a particularly important role in obtaining our final model samples. We find that the pMSSM leads to a much broader set of predictions for the properties of the SUSY partners as well as for a number of experimental observables than those found in any of the conventional SUSY breaking scenarios such as mSUGRA. This set of models can easily lead to atypical expectations for SUSY signals at the LHC.
Reach of the CERN LHC for the Minimal Anomaly-Mediated SUSY Breaking Model
Baer, Howard W; Tata, Xerxes; Baer, Howard; Tata, Xerxes
2000-01-01
We examine the reach of the CERN LHC pp collider for supersymmetric models where the dominant contribution to soft SUSY breaking parameters arises from the superconformal anomaly. In the simplest viable anomaly mediated SUSY breaking (AMSB) model, tachyonic slepton squared masses are made positive by adding a universal contribution m_0^2 to all scalars. We use the event generator ISAJET to generate AMSB signal events as a function of model parameter space. Assuming an integrated luminosity of 10 fb-1, the LHC can reach to values of $m_{\\tg}\\sim 2.3$ TeV for low values of $m_0$, where the dilepton plus jets plus E_T(missing) channel offers the best reach. For large $m_0$, the best signature is typically 0 or 1 isolated lepton plus jets plus E_T(missing); in this case the reach is typically diminished to values of $m_{\\tg}\\sim 1.3$ TeV. The presence of terminating tracks in a subset of signal events could serve to verify the presence of a long lived lightest chargino which is generic in the minimal AMSB model.
SUSY + Beyond Standard Model Higgs Searches at the Tevatron
Directory of Open Access Journals (Sweden)
Abid Patwa
2012-06-01
Full Text Available Recent results by the CDF and DØ Collaborations for non-Standard Model Higgs boson searches in pp¯ $par p$ collisions at center-of-mass energy of √s = 1.96 TeV using up to 8.2 fb−1 of Fermilab Tevatron data are discussed. Searches for neutral Higgs bosons predicted in the Minimal Supersymmetric Standard Model (MSSM, doubly-charged Higgs bosons predicted in extended models, as well as Higgs bosons within Hidden Valley and Fermiophobic models are described.
SARAH 4: A tool for (not only SUSY) model builders
Staub, Florian
2014-06-01
We present the new version of the Mathematica package SARAH which provides the same features for a non-supersymmetric model as previous versions for supersymmetric models. This includes an easy and straightforward definition of the model, the calculation of all vertices, mass matrices, tadpole equations, and self-energies. Also the two-loop renormalization group equations for a general gauge theory are now included and have been validated with the independent Python code PyR@TE. Model files for FeynArts, CalcHep/CompHep, WHIZARD and in the UFO format can be written, and source code for SPheno for the calculation of the mass spectrum, a set of precision observables, and the decay widths and branching ratios of all states can be generated. Furthermore, the new version includes routines to output model files for Vevacious for both, supersymmetric and non-supersymmetric, models. Global symmetries are also supported with this version and by linking Susyno the handling of Lie groups has been improved and extended.
Confronting SUSY models with LHC data via electroweakino production
Energy Technology Data Exchange (ETDEWEB)
Arina, Chiara [Univ. Catholique de Louvain, Louvain-la-Neuve (Belgium). Centre for Cosmology, Particle Physics and Phenomology (CP3); Chala, Mikael [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Martin-Lozano, Victor [Univ. Autonoma de Madrid UAM/CSIC (Spain). Dept. de Fisica Teorica y Inst. de Fisica Teorica; Bonn Univ. (Germany). Bethe Center for Theoretical Physics und Physikalisches Inst.; Nardini, Germano [Bern Univ. (Switzerland). Inst. fuer Theoretische Physik
2016-12-15
We investigate multi-lepton signals produced by ElectroWeakino (EWino) decays in the MSSM and the TMSSM scenarios with sfermions, gluinos and non Standard Model Higgses at the TeV scale, being the Bino electroweak-scale dark matter. We recast the present LHC constraints on EWinos for these models and we find that wide MSSM and TMSSM parameter regions prove to be allowed. We forecast the number of events expected in the signal regions of the experimental multi-lepton analyses in the next LHC runs. The correlations among these numbers will help to determine whether future deviations in multi-lepton data are ascribable to the EWinos, as well as the supersymmetric model they originate from.
Global fits of GUT-scale SUSY models with GAMBIT
Athron, Peter; Balázs, Csaba; Bringmann, Torsten; Buckley, Andy; Chrząszcz, Marcin; Conrad, Jan; Cornell, Jonathan M.; Dal, Lars A.; Edsjö, Joakim; Farmer, Ben; Jackson, Paul; Krislock, Abram; Kvellestad, Anders; Mahmoudi, Farvah; Martinez, Gregory D.; Putze, Antje; Raklev, Are; Rogan, Christopher; de Austri, Roberto Ruiz; Saavedra, Aldo; Savage, Christopher; Scott, Pat; Serra, Nicola; Weniger, Christoph; White, Martin
2017-12-01
We present the most comprehensive global fits to date of three supersymmetric models motivated by grand unification: the constrained minimal supersymmetric standard model (CMSSM), and its Non-Universal Higgs Mass generalisations NUHM1 and NUHM2. We include likelihoods from a number of direct and indirect dark matter searches, a large collection of electroweak precision and flavour observables, direct searches for supersymmetry at LEP and Runs I and II of the LHC, and constraints from Higgs observables. Our analysis improves on existing results not only in terms of the number of included observables, but also in the level of detail with which we treat them, our sampling techniques for scanning the parameter space, and our treatment of nuisance parameters. We show that stau co-annihilation is now ruled out in the CMSSM at more than 95% confidence. Stop co-annihilation turns out to be one of the most promising mechanisms for achieving an appropriate relic density of dark matter in all three models, whilst avoiding all other constraints. We find high-likelihood regions of parameter space featuring light stops and charginos, making them potentially detectable in the near future at the LHC. We also show that tonne-scale direct detection will play a largely complementary role, probing large parts of the remaining viable parameter space, including essentially all models with multi-TeV neutralinos.
SUSY Breaking in Local String/F-Theory Models
Blumenhagen, R; Krippendorf, S; Moster, S; Quevedo, F
2009-01-01
We investigate bulk moduli stabilisation and supersymmetry breaking in local string/F-theory models where the Standard Model is supported on a del Pezzo surface or singularity. Computing the gravity mediated soft terms on the Standard Model brane induced by bulk supersymmetry breaking in the LARGE volume scenario, we explicitly find suppressions by M_s/M_P ~ V^{-1/2} compared to M_{3/2}. This gives rise to several phenomenological scenarios, depending on the strength of perturbative corrections to the effective action and the source of de Sitter lifting, in which the soft terms are suppressed by at least M_P/V^{3/2} and may be as small as M_P/V^2. Since the gravitino mass is of order M_{3/2} ~ M_P/V, for TeV soft terms all these scenarios give a very heavy gravitino (M_{3/2} >= 10^8 GeV) and generically the lightest moduli field is also heavy enough (m >= 10 TeV) to avoid the cosmological moduli problem. For TeV soft terms, these scenarios predict a minimal value of the volume to be V ~ 10^{6-7} in string uni...
The di-photon excess in a perturbative SUSY model
Energy Technology Data Exchange (ETDEWEB)
Benakli, Karim, E-mail: kbenakli@lpthe.jussieu.fr [Sorbonne Universités, UPMC Univ Paris 06, UMR 7589, LPTHE, F-75005, Paris (France); CNRS, UMR 7589, LPTHE, F-75005, Paris (France); Darmé, Luc, E-mail: darme@lpthe.jussieu.fr [Sorbonne Universités, UPMC Univ Paris 06, UMR 7589, LPTHE, F-75005, Paris (France); CNRS, UMR 7589, LPTHE, F-75005, Paris (France); Sorbonne Universités, Institut Lagrange de Paris (ILP), 98 bis Boulevard Arago, 75014 Paris (France); Goodsell, Mark D., E-mail: goodsell@lpthe.jussieu.fr [Sorbonne Universités, UPMC Univ Paris 06, UMR 7589, LPTHE, F-75005, Paris (France); CNRS, UMR 7589, LPTHE, F-75005, Paris (France); Harz, Julia, E-mail: jharz@lpthe.jussieu.fr [Sorbonne Universités, UPMC Univ Paris 06, UMR 7589, LPTHE, F-75005, Paris (France); CNRS, UMR 7589, LPTHE, F-75005, Paris (France); Sorbonne Universités, Institut Lagrange de Paris (ILP), 98 bis Boulevard Arago, 75014 Paris (France)
2016-10-15
We show that a 750 GeV di-photon excess as reported by the ATLAS and CMS experiments can be reproduced by the Minimal Dirac Gaugino Supersymmetric Standard Model (MDGSSM) without the need of any ad-hoc addition of new states. The scalar resonance is identified with the spin-0 partner of the Dirac bino. We perform a thorough analysis of constraints coming from the mixing of the scalar with the Higgs boson, the stability of the vacuum and the requirement of perturbativity of the couplings up to very high energy scales. We exhibit examples of regions of the parameter space that respect all the constraints while reproducing the excess. We point out how trilinear couplings that are expected to arise in supersymmetry-breaking mediation scenarios, but were ignored in the previous literature on the subject, play an important role.
The di-photon excess in a perturbative SUSY model
Directory of Open Access Journals (Sweden)
Karim Benakli
2016-10-01
Full Text Available We show that a 750 GeV di-photon excess as reported by the ATLAS and CMS experiments can be reproduced by the Minimal Dirac Gaugino Supersymmetric Standard Model (MDGSSM without the need of any ad-hoc addition of new states. The scalar resonance is identified with the spin-0 partner of the Dirac bino. We perform a thorough analysis of constraints coming from the mixing of the scalar with the Higgs boson, the stability of the vacuum and the requirement of perturbativity of the couplings up to very high energy scales. We exhibit examples of regions of the parameter space that respect all the constraints while reproducing the excess. We point out how trilinear couplings that are expected to arise in supersymmetry-breaking mediation scenarios, but were ignored in the previous literature on the subject, play an important role.
The flavor and CP problems in SUSY
Masiero, A
2004-01-01
Although direct searches of supersymmetry (SUSY) constitute the only way we have to clearly verify the existence of a low-energy SUSY extension of the standard model, yet, in particular in our pre-LHC era, it is of utmost importance to study any possible signal where SUSY manifests itself indirectly in discrepancies with the SM expectations in rare processes. In this talk we'll consider a wide range of flavor changing neutral current and/or CP violating phenomena where, indeed, SUSY contributions are comparable to the SM ones. Such analysis provides stringent constraints on different SUSY model parameter spaces and, at the same time, it individuates possible windows for SUSY signals in spite of all the existing constraints. Our attention will focus in particular on the CP violating processes which are the most sensitive place for SUSY effects in the vast class of rare phenomena of the SM.
Q{sub 6} as the flavor symmetry in a non-minimal SUSY SU(5) model
Energy Technology Data Exchange (ETDEWEB)
Gomez-Izquierdo, J.C.; Mondragon, M [Universidad Nacional Autonoma de Mexico, Instituto de Fisica, Mexico, DF (Mexico); Gonzalez-Canales, F. [Benemerita Universidad Autonoma, Facultad de Ciencias de la Electronica, Puebla, Puebla (Mexico); Instituto de Fisica Corpuscular-CSIC/Universitat de Valencia, AHEP Group, Paterna, Valencia (Spain)
2015-05-15
We present a non-minimal renormalizable SUSY SU(5) model, with extended Higgs sector and right-handed neutrinos, where the flavor sector exhibits a Q{sub 6} flavor symmetry. We analyzed the simplest version of this model, in which R-parity is conserved and the right-handed neutrino masses in the flavor doublet are considered with and without degeneracy. We find the generic form of the mass matrices both in the quark and lepton sectors. We reproduce, according to current data, the mixing in the CKM matrix. In the leptonic sector, in the general case where the right-handed neutrino masses are not degenerate, we find that the values for the solar, atmospheric, and reactor mixing angles are in very good agreement with the experimental data, both for a normal and an inverted hierarchy. In the particular case where the right-handed neutrinos masses are degenerate, the model predicts a strong inverted hierarchy spectrum and a sum rule among the neutrino masses. In this case the atmospheric and solar angles are in very good agreement with experimental data, and the reactor one is different from zero, albeit too small (θ{sub 13}{sup l{sup t{sup h}}}). This value constitutes a lower bound for θ{sub 13} in the general case.We also find the range of the values for the neutrino masses in each case. (orig.)
Xu, Da; The ATLAS collaboration
2018-01-01
Despite the absence of experimental evidence, weak scale supersymmetry remains one of the best motivated and studied Standard Model extensions. This talk gives an overview of the most recent SUSY searches in ATLAS and CMS experiments using 13 TeV ATLAS Run2 data.
Baumgart, Matthew; Zorawski, Thomas
2014-01-01
Radiative flavor models where the hierarchies of Standard Model (SM) fermion masses and mixings are explained via loop corrections are elegant ways to solve the SM flavor puzzle. Here we build such a model in the context of Mini-Split Supersymmetry (SUSY) where both flavor and SUSY breaking occur at a scale of 1000 TeV. This model is consistent with the observed Higgs mass, unification, and WIMP dark matter. The high scale allows large flavor mixing among the sfermions, which provides part of the mechanism for radiative flavor generation. In the deep UV, all flavors are treated democratically, but at the SUSY breaking scale, the third, second, and first generation Yukawa couplings are generated at tree level, one loop, and two loops, respectively. Save for one, all the dimensionless parameters in the theory are O(1), with the exception being a modest and technically natural tuning that explains both the smallness of the bottom Yukawa coupling and the largeness of the Cabibbo angle.
Constraining SUSY models with Fittino using measurements before, with and beyond the LHC
Energy Technology Data Exchange (ETDEWEB)
Bechtle, Philip [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Desch, Klaus; Uhlenbrock, Mathias; Wienemann, Peter [Bonn Univ. (Germany). Physikalisches Inst.
2009-07-15
We investigate the constraints on Supersymmetry (SUSY) arising from available precision measurements using a global fit approach.When interpreted within minimal supergravity (mSUGRA), the data provide significant constraints on the masses of supersymmetric particles (sparticles), which are predicted to be light enough for an early discovery at the Large Hadron Collider (LHC). We provide predicted mass spectra including, for the first time, full uncertainty bands. The most stringent constraint is from the measurement of the anomalous magnetic moment of the muon. Using the results of these fits, we investigate to which precision mSUGRA and more general MSSM parameters can be measured by the LHC experiments with three different integrated luminosities for a parameter point which approximately lies in the region preferred by current data. The impact of the already available measurements on these precisions, when combined with LHC data, is also studied. We develop a method to treat ambiguities arising from different interpretations of the data within one model and provide a way to differentiate between values of different digital parameters of a model (e. g. sign({mu}) within mSUGRA). Finally, we show how measurements at a linear collider with up to 1 TeV centre-of-mass energy will help to improve precision by an order of magnitude. (orig.)
Liu, Xiaohui; Mantry, Sonny; Petriello, Frank
2012-03-01
Supersymmetry has been one of the most popular candidates for physics beyond standard model (SM) for a long time. The fact that we haven't yet discover super particles in nowadays LHC data, pushes the SUSY production nearer and nearer to the LHC machine threshold. In the threshold limit, how well we understand the SM background is crucial for SUSY or other physics beyond SM search. In this talk, we will use the simplest case by considering photon plus two jets events to address the problem and we will talk about how we use the soft collinear effective theory to sum up potentially large logs related to threshold limit to improve our understanding of the SM background.
The fine-tuning cost of the likelihood in SUSY models
Ghilencea, D M
2013-01-01
In SUSY models, the fine tuning of the electroweak (EW) scale with respect to their parameters gamma_i={m_0, m_{1/2}, mu_0, A_0, B_0,...} and the maximal likelihood L to fit the experimental data are usually regarded as two different problems. We show that, if one regards the EW minimum conditions as constraints that fix the EW scale, this commonly held view is not correct and that the likelihood contains all the information about fine-tuning. In this case we show that the corrected likelihood is equal to the ratio L/Delta of the usual likelihood L and the traditional fine tuning measure Delta of the EW scale. A similar result is obtained for the integrated likelihood over the set {gamma_i}, that can be written as a surface integral of the ratio L/Delta, with the surface in gamma_i space determined by the EW minimum constraints. As a result, a large likelihood actually demands a large ratio L/Delta or equivalently, a small chi^2_{new}=chi^2_{old}+2*ln(Delta). This shows the fine-tuning cost to the likelihood ...
SUSY with ATLAS Leptonic Signatures, Coannihilation Region
Comune, G
2004-01-01
In this work we present an initial study on how leptonic signatures can be used at ATLAS to constrain SUSY particle masses combinations for the first time in the so called "coannihilation region''. The analysis is carried out in the framework of mSUGRA constrained SUSY model using fast detector simulation and reconstruction exploiting an invariant mass endpoint technique.
Search for beyond standard model physics (non-SUSY) in final states with photons at the Tevatron
Energy Technology Data Exchange (ETDEWEB)
Palencia, Jose Enrique; /Fermilab
2009-01-01
We present the results of searches for non-standard model phenomena in photon final states. These searches use data from integrated luminosities of {approx} 1-4 fb{sup -1} of p{bar p} collisions at {radical}s = 1.96 TeV, collected with the CDF and D0 detectors at the Fermilab Tevatron. No significant excess in data has been observed. We report limits on the parameters of several BSM models (excluding SUSY) for events containing photons.
Generalized Jaynes-Cummings Hamiltonians by shape-invariant hierarchies and their SUSY partners
Energy Technology Data Exchange (ETDEWEB)
Hussin, V [Centre de recherches mathematiques et Departement de mathematiques et de statistique, Universite de Montreal, C P 6128, succ. Centre-ville, Montreal (Quebec), H3C 3J7 (Canada); Kuru, S [Departamento de Fisica Teorica, Atomica y Optica, Universidad de Valladolid, 47071 Valladolid (Spain); Negro, J [Departamento de Fisica Teorica, Atomica y Optica, Universidad de Valladolid, 47071 Valladolid (Spain)
2006-09-08
A generalization of the matrix Jaynes-Cummings model in the rotating wave approximation is proposed by means of the shape-invariant hierarchies of scalar factorized Hamiltonians. A class of Darboux transformations (sometimes called SUSY transformations in this context) suitable for these generalized Jaynes-Cummings models is constructed. Finally one example is worked out using the methods developed.
Directory of Open Access Journals (Sweden)
Mauricio Valenzuela
2017-10-01
Full Text Available We propose a hybrid class of theories for higher spin gravity and matrix models, i.e., which handle simultaneously higher spin gravity fields and matrix models. The construction is similar to Vasiliev’s higher spin gravity, but part of the equations of motion are provided by the action principle of a matrix model. In particular, we construct a higher spin (gravity matrix model related to type IIB matrix models/string theory that have a well defined classical limit, and which is compatible with higher spin gravity in A d S space. As it has been suggested that higher spin gravity should be related to string theory in a high energy (tensionless regime, and, therefore to M-Theory, we expect that our construction will be useful to explore concrete connections.
Calculating the renormalisation group equations of a SUSY model with Susyno
Fonseca, Renato M.
2012-10-01
Susyno is a Mathematica package dedicated to the computation of the 2-loop renormalisation group equations of a supersymmetric model based on any gauge group (the only exception being multiple U(1) groups) and for any field content. Program summary Program title: Susyno Catalogue identifier: AEMX_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEMX_v1_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 30829 No. of bytes in distributed program, including test data, etc.: 650170 Distribution format: tar.gz Programming language: Mathematica 7 or higher. Computer: All systems that Mathematica 7+ is available for (PC, Mac). Operating system: Any platform supporting Mathematica 7+ (Windows, Linux, Mac OS). Classification: 4.2, 5, 11.1. Nature of problem: Calculating the renormalisation group equations of a supersymmetric model involves using long and complicated general formulae [1, 2]. In addition, to apply them it is necessary to know the Lagrangian in its full form. Building the complete Lagrangian of models with small representations of SU(2) and SU(3) might be easy but in the general case of arbitrary representations of an arbitrary gauge group, this task can be hard, lengthy and error prone. Solution method: The Susyno package uses group theoretical functions to calculate the super-potential and the soft-SUSY-breaking Lagrangian of a supersymmetric model, and calculates the two-loop RGEs of the model using the general equations of [1, 2]. Susyno works for models based on any representation(s) of any gauge group (the only exception being multiple U(1) groups). Restrictions: As the program is based on the formalism of [1, 2], it shares its limitations. Running time can also be a significant restriction, in particular for models with many fields. Unusual features
Energy Technology Data Exchange (ETDEWEB)
Brown, T.W.
2010-11-15
The same complex matrix model calculates both tachyon scattering for the c=1 non-critical string at the self-dual radius and certain correlation functions of half-BPS operators in N=4 super- Yang-Mills. It is dual to another complex matrix model where the couplings of the first model are encoded in the Kontsevich-like variables of the second. The duality between the theories is mirrored by the duality of their Feynman diagrams. Analogously to the Hermitian Kontsevich- Penner model, the correlation functions of the second model can be written as sums over discrete points in subspaces of the moduli space of punctured Riemann surfaces. (orig.)
Predicting the sparticle spectrum from GUTs via SUSY threshold corrections with SusyTC
Energy Technology Data Exchange (ETDEWEB)
Antusch, Stefan [Department of Physics, University of Basel,Klingelbergstr. 82, CH-4056 Basel (Switzerland); Max-Planck-Institut für Physik (Werner-Heisenberg-Institut),Föhringer Ring 6, D-80805 München (Germany); Sluka, Constantin [Department of Physics, University of Basel,Klingelbergstr. 82, CH-4056 Basel (Switzerland)
2016-07-21
Grand Unified Theories (GUTs) can feature predictions for the ratios of quark and lepton Yukawa couplings at high energy, which can be tested with the increasingly precise results for the fermion masses, given at low energies. To perform such tests, the renormalization group (RG) running has to be performed with sufficient accuracy. In supersymmetric (SUSY) theories, the one-loop threshold corrections (TC) are of particular importance and, since they affect the quark-lepton mass relations, link a given GUT flavour model to the sparticle spectrum. To accurately study such predictions, we extend and generalize various formulas in the literature which are needed for a precision analysis of SUSY flavour GUT models. We introduce the new software tool SusyTC, a major extension to the Mathematica package REAP http://dx.doi.org/10.1088/1126-6708/2005/03/024, where these formulas are implemented. SusyTC extends the functionality of REAP by a full inclusion of the (complex) MSSM SUSY sector and a careful calculation of the one-loop SUSY threshold corrections for the full down-type quark, up-type quark and charged lepton Yukawa coupling matrices in the electroweak-unbroken phase. Among other useful features, SusyTC calculates the one-loop corrected pole mass of the charged (or the CP-odd) Higgs boson as well as provides output in SLHA conventions, i.e. the necessary input for external software, e.g. for performing a two-loop Higgs mass calculation. We apply SusyTC to study the predictions for the parameters of the CMSSM (mSUGRA) SUSY scenario from the set of GUT scale Yukawa relations ((y{sub e})/(y{sub d}))=−(1/2), ((y{sub μ})/(y{sub s}))=6, and ((y{sub τ})/(y{sub b}))=−(3/2), which has been proposed recently in the context of SUSY GUT flavour models.
Sopczak, Andre; The ATLAS collaboration
2017-01-01
During the data-taking period at LHC (Run-II), several searches for supersymmetric particles were performed. The results from searches by the ATLAS collaborations are concisely reviewed. Model-independent and model-dependent limits on new particle production are set, and interpretations in supersymmetric models are given.
Sopczak, Andre; The ATLAS collaboration
2017-01-01
During the LHC Run-II data-taking period, several searches for supersymmetric particles were performed by the ATLAS collaboration. The results from these searches are concisely reviewed. Model-independent and model-dependent limits on new particle production are set, and interpretations in supersymmetric models are given.
SUSY Searches in the ATLAS Experiment
Lee JR, Lawrence; The ATLAS collaboration
2014-01-01
Despite the absence of experimental evidence, weak scale supersymmetry remains one of the best motivated and studied Standard Model extensions. This talk summarises recent ATLAS results for searches for supersymmetric (SUSY) particles. Weak and strong production in both R-Parity conserving and R-Parity violating SUSY scenarios are considered. The searches involved final states including jets, missing transverse momentum, light leptons, taus or photons, as well as long-lived particle signatures.
Inclusive SUSY searches at the LHC
Sekmen, Sezen
2014-01-01
I summarize the status of the inclusive SUSY searches conducted by the ATLAS and CMS experiments using the 20 fb-1 of 8 TeV LHC data in the all inclusive, 0 lepton, >=1 lepton and >=2 lepton final states. Current searches show that data are consistent with the SM. The impact of this consistency was explored on a rich variety of SUSY scenarios and simplified models, examples of which I present here.
Yuanyuan, Zhang
The stochastic branching model of multi-particle productions in high energy collision has theoretical basis in perturbative QCD, and also successfully describes the experimental data for a wide energy range. However, over the years, little attention has been put on the branching model for supersymmetric (SUSY) particles. In this thesis, a stochastic branching model has been built to describe the pure supersymmetric particle jets evolution. This model is a modified two-phase stochastic branching process, or more precisely a two phase Simple Birth Process plus Poisson Process. The general case that the jets contain both ordinary particle jets and supersymmetric particle jets has also been investigated. We get the multiplicity distribution of the general case, which contains a Hypergeometric function in its expression. We apply this new multiplicity distribution to the current experimental data of pp collision at center of mass energy √s = 0.9, 2.36, 7 TeV. The fitting shows the supersymmetric particles haven't participate branching at current collision energy.
SUSY searches at LHC and Dark Matter
Barberio, E; The ATLAS collaboration
2009-01-01
Supersymmetric models with R-parity conservation provide an excellent can- didate for Dark Matter, the Lightest Supersymmetric Particle, which will be searched for with the ATLAS detector at the Large Hadron Collider (LHC). Based on recent simulation studies, we present the discovery potential for Su- persymmetry (SUSY) with the ﬁrst few fb−1 of ATLAS data, as well as studies of the techniques used to reconstruct decays of SUSY particles at the LHC. We further discuss how such measurements can be used to constrain the underly- ing Supersymmetric model and hence to extract information about the nature of Dark Matter.
Strategy for early SUSY searches at ATLAS
Yamamoto, S
2007-01-01
The CERN Large Hadron Collider (LHC) is scheduled to commence operation in 2008 and inclusive searches for supersymmetry (SUSY) will be one of our primary tasks in the first days of LHC operation. It is certain that the final state of âﾜmultijets + missing transverse energyâ will provide a superior performance in SUSY searches. As yet, well-considered strategies for the understanding of instrumental effects of detectors and the realistic estimations of the Standard Model (SM) backgrounds would not be clear: they are urgent issues for the coming data. We describe the strategy for early SUSY searches at the ATLAS experiment using the fist data corresponding to the integrated luminosity up to 1fbâ1, which comprises many progresses in the data-driven technique for the SM background estimations.
Strategy for early SUSY searches at ATLAS
Yamamoto, Shimpei
2008-01-01
The CERN Large Hadron Collider (LHC) is scheduled to commence operation in 2008 and inclusive searches for supersymmetry (SUSY) will be one of our primary tasks in the first days of LHC operation. It is certain that the final state of multijets plus missing transverse energy will provide a superior performance in SUSY searches. As yet, well-considered strategies for the understanding of instrumental effects of detectors and the realistic estimations of the Standard Model (SM) backgrounds would not be clear: they are urgent issues for the coming data. We describe the strategy for early SUSY searches at the ATLAS experiment using the fist data corresponding to the integrated luminosity up to 1fb^-1, which comprises many progresses in the data-driven technique for the SM background estimations.
Strategy for early SUSY searches at ATLAS
Yamamoto, S
2007-01-01
The CERN Large Hadron Collider (LHC) is scheduled to commence operation in 2008 and inclusive searches for supersymmetry (SUSY) will be one of our primary tasks in the first days of LHC operation. It is certain that the final state of multijets plus missing transverse energy will provide a superior performance in SUSY searches. As yet, well-considered strategies for the understanding of instrumental effects of detectors and the realistic estimations of the Standard Model (SM) backgrounds would not be clear: they are urgent issues for the coming data. We describe the strategy for early SUSY searches at the ATLAS experiment using the fist data corresponding to the integrated luminosity up to 1fb^-1, which includes many progresses in the data-driven technique for the SM background estimations.
Matrix algebra for linear models
Gruber, Marvin H J
2013-01-01
Matrix methods have evolved from a tool for expressing statistical problems to an indispensable part of the development, understanding, and use of various types of complex statistical analyses. This evolution has made matrix methods a vital part of statistical education. Traditionally, matrix methods are taught in courses on everything from regression analysis to stochastic processes, thus creating a fractured view of the topic. Matrix Algebra for Linear Models offers readers a unique, unified view of matrix analysis theory (where and when necessary), methods, and their applications. Written f
Papucci, Michele; Ruderman, Joshua T.; Weiler, Andreas
2012-09-01
The first 1 fb-1 of LHC searches have set impressive limits on new colored particles decaying to missing energy. We address the implication of these searches for naturalness in supersymmetry (SUSY). General bottom-up considerations of natural electroweak symmetry breaking show that higgsinos, stops, and the gluino should not be too far above the weak scale. The rest of the spectrum, including the squarks of the first two generations, can be heavier and beyond the current LHC reach. We have used collider simulations to determine the limits that all of the 1 fb-1 searches pose on higgsinos, stops, and the gluino. We find that stops and the left-handed sbottom are starting to be constrained and must be heavier than about 200-300 GeV when decaying to higgsinos. The gluino must be heavier than about 600-800 GeV when it decays to stops and sbottoms. While these findings point toward scenarios with a lighter third generation split from the other squarks, we do find that moderately-tuned regions remain, where the gluino is just above 1 TeV and all the squarks are degenerate and light. Among all the searches, jets plus missing energy and same-sign dileptons often provide the most powerful probes of natural SUSY. Overall, our results indicate that natural SUSY has survived the first 1 fb-1 of data. The LHC is now on the brink of exploring the most interesting region of SUSY parameter space.
SUSY searches with the ATLAS detector
Bianchi, Riccardo-Maria; The ATLAS collaboration
2017-01-01
Despite the absence of experimental evidence, weak scale supersymmetry remains one of the best motivated and studied Standard Model extensions. This talk summarises recent ATLAS results for searches for supersymmetric (SUSY) particles, with focus on those obtained using proton-proton collisions at a centre of mass energy of 13 \\TeV. Strong production in both R-Parity conserving and R-Parity violating SUSY scenarios are considered. The searches involved final states including jets, missing transverse momentum, light leptons, as well as long-lived particle signatures.
SUSY searches with the ATLAS detector
Directory of Open Access Journals (Sweden)
BIANCHI Riccardo Maria
2017-01-01
Full Text Available Despite the absence of experimental evidence, weak scale supersymmetry remains one of the best motivated and studied Standard Model extensions. This talk summarises recent ATLAS results for searches for supersymmetric (SUSY particles, with focus on those obtained using proton-proton collisions at a centre of mass energy of 13 TeV. Strong production in both R-Parity conserving and R-Parity violating SUSY scenarios are considered. The searches involved final states including jets, missing transverse momentum, light leptons, as well as long-lived particle signatures.
SUSY searches with the ATLAS detector
Ventura, Andrea; The ATLAS collaboration
2016-01-01
Despite the absence of experimental evidence, weak scale supersymmetry remains one of the best motivated and studied Standard Model extensions. This talk summarises recent ATLAS results for searches for supersymmetric (SUSY) particles, with focus on those obtained using proton-proton collisions at a centre of mass energy of 13 TeV. Strong production in both R-Parity conserving and R-Parity violating SUSY scenarios are considered. The searches involved final states including jets, missing transverse momentum, light leptons, as well as long-lived particle signatures.
Andric, I; Jurman, D; Nielsen, H B
2007-01-01
We discuss a dynamical matrix model by which probability distribution is associated with Gaussian ensembles from random matrix theory. We interpret the matrix M as a Hamiltonian representing interaction of a bosonic system with a single fermion. We show that a system of second-quantized fermions influences the ground state of the whole system by producing a gap between the highest occupied eigenvalue and the lowest unoccupied eigenvalue.
The hyperbolic step potential: Anti-bound states, SUSY partners and Wigner time delays
Energy Technology Data Exchange (ETDEWEB)
Gadella, M. [Departamento de Física Teórica, Atómica y Óptica and IMUVA, Universidad de Valladolid, E-47011 Valladolid (Spain); Kuru, Ş. [Department of Physics, Faculty of Science, Ankara University, 06100 Ankara (Turkey); Negro, J., E-mail: jnegro@fta.uva.es [Departamento de Física Teórica, Atómica y Óptica and IMUVA, Universidad de Valladolid, E-47011 Valladolid (Spain)
2017-04-15
We study the scattering produced by a one dimensional hyperbolic step potential, which is exactly solvable and shows an unusual interest because of its asymmetric character. The analytic continuation of the scattering matrix in the momentum representation has a branch cut and an infinite number of simple poles on the negative imaginary axis which are related with the so called anti-bound states. This model does not show resonances. Using the wave functions of the anti-bound states, we obtain supersymmetric (SUSY) partners which are the series of Rosen–Morse II potentials. We have computed the Wigner reflection and transmission time delays for the hyperbolic step and such SUSY partners. Our results show that the more bound states a partner Hamiltonian has the smaller is the time delay. We also have evaluated time delays for the hyperbolic step potential in the classical case and have obtained striking similitudes with the quantum case. - Highlights: • The scattering matrix of hyperbolic step potential is studied. • The scattering matrix has a branch cut and an infinite number of poles. • The poles are associated to anti-bound states. • Susy partners using antibound states are computed. • Wigner time delays for the hyperbolic step and partner potentials are compared.
Non-SUSY WIMPS: simplified models and Dark Matter at the LHC
Morgante, Enrico
2017-01-01
I discuss the construction of Simplified Models for Dark Matter searches at the LHC. After reviewing the phylosophy and some simple example, I turn the attention to the aspect of the theoretical consistency of these models.
SARAH goes left and right looking beyond the Standard Model and meets SUSY
Energy Technology Data Exchange (ETDEWEB)
Opferkuch, Toby Oliver
2017-07-07
Progress in the search for physics beyond the Standard Model (BSM) proceeds through two main avenues. The first requires the development of models that address the host of theoretical and experimental deficiencies of the Standard Model (SM). The second avenue requires scrutinising these models against all available data as well as checks for theoretical consistency. Unfortunately there exists a large number of strongly motivated models as well as an absence of any signs illuminating the correct path nature has chosen. With the lack of a clear direction, automated tools provide an effective means to test as many models as possible. In this thesis we demonstrate how the SARAH framework can be used in this context as well as its adaptability for confronting unexpected hints of new physics, such as the diphoton excess, that have arisen at the Large Hadron Collider (LHC) over the previous years. We then turn to more theoretical constraints namely, studying the stability of the electroweak vacuum in minimal supersymmetric models. Here we studied the impact of previously neglected directions when including non-standard vacuum expectation values. In the second half of this thesis we consider low-scale left-right symmetric models both with and without supersymmetry. In the non-supersymmetric case we consider constraints arising from charged lepton flavour violation. We have significantly improved existing parametrisations allowing for the new Yukawa couplings to be determined as a function of the underlying model parameters. The last scenario we consider is a model based on SO(10) unification at the high-scale. We build a complete model with TeV-scale breaking of the left-right phase studying in detail the phenomenology.
Data driven background determination for SUSY searches with ATLAS
Koutsman, AJ
2009-01-01
Supersymmetry(SUSY) is an attractive extension of the Standard Model solving many standing issues in particle physics and cosmology. The general purpose ATLAS detector at the Large Hadron Collider (LHC) is an excellent experiment to discover or exclude TeV SUSY. However discovery can only be claimed when the Standard Model backgrounds are understood and are under control. The expectations at the LHC are that Monte Carlo predictions will not be sufficient to achieve this, the backgrounds will have to determined from data itself. In this talk we will highlight some data driven methods developed to estimate backgrounds and measure a possible SUSY excess.
A SUSY inspired simplified model for the 750 GeV diphoton excess
Directory of Open Access Journals (Sweden)
E. Gabrielli
2016-05-01
Full Text Available The evidence for a new neutral scalar particle from the 750 GeV diphoton excess, and the absence of any other signal of new physics at the LHC so far, suggests the existence of new coloured scalars. To study this possibility, we propose a supersymmetry inspired simplified model, extending the Standard Model with a singlet scalar and with heavy scalar fields carrying both colour and electric charges – new scalar quarks. To allow the latter to decay, and to generate the dark matter of the Universe, we also add a neutral fermion to the particle content. We show that this model provides a two-parameter fit to the observed diphoton excess consistently with cosmology, while the allowed parameter space is bounded by the consistency of the model. In the context of our simplified model this implies the existence of other supersymmetric particles accessible at the LHC, rendering this scenario falsifiable.
Energy Technology Data Exchange (ETDEWEB)
Papucci, Michele; Ruderman, Joshua T. [Lawrence Berkeley National Laboratory, CA (United States). Theoretical Physics Group; California Univ., Berkeley, CA (United States). Dept. of Physics; Weiler, Andreas [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); European Organization for Nuclear Research, Geneva (Switzerland). Theoretical Physics Div.
2011-10-31
The first 1 fb{sup -1} of LHC searches have set impressive limits on new colored particles decaying to missing energy. We address the implication of these searches for naturalness in supersymmetry (SUSY). General bottom-up considerations of natural electroweak symmetry breaking show that higgsinos, stops, and the gluino should not be too far above the weak scale. The rest of the spectrum, including the squarks of the first two generations, can be heavier and beyond the current LHC reach. We have used collider simulations to determine the limits that all of the 1 fb{sup -1} searches pose on higgsinos, stops, and the gluino. We find that stops and the left-handed sbottom are starting to be constrained and must be heavier than about 200-300 GeV when decaying to higgsinos. The gluino must be heavier than about 600-800 GeV when it decays to stops and sbottoms. While these findings point toward scenarios with a lighter third generation split from the other squarks, we do find that moderately-tuned regions remain, where the gluino is just above 1 TeV and all the squarks are degenerate and light. Among all the searches, jets plus missing energy and same-sign dileptons often provide the most powerful probes of natural SUSY. Overall, our results indicate that natural SUSY has survived the first 1 fb{sup -1} of data. The LHC is now on the brink of exploring the most interesting region of SUSY parameter space. (orig.)
The Higgs Sector of the Minimal SUSY B-L Model
Directory of Open Access Journals (Sweden)
Lorenzo Basso
2015-01-01
Full Text Available I review the Higgs sector of the U(1B-L extension of the minimal supersymmetric standard model (MSSM. I will show that the gauge kinetic mixing plays a crucial role in the Higgs phenomenology. Two light bosons are present, a MSSM-like one and a B-L-like one, which mix at one loop solely due to the gauge mixing. After briefly looking at constraints from flavour observables, new decay channels involving right-handed (sneutrinos are presented. Finally, how model features pertaining to the gauge extension affect the model phenomenology, concerning the existence of R-Parity-conserving minima at loop level and the Higgs-to-diphoton coupling, will be reviewed.
Muon anomalous magnetic moment in SUSY B−L model with inverse seesaw
Directory of Open Access Journals (Sweden)
Shaaban Khalil
2016-12-01
Full Text Available Motivated by the tension between the Higgs mass and muon g−2 in minimal supersymmetric standard model (MSSM, we analyze the muon g−2 in supersymmetric B−L extension of the standard model (BLSSM with inverse seesaw mechanism. In this model, the Higgs mass receives extra important radiative corrections proportional to large neutrino Yukawa coupling. We point out that muon g−2 also gets significant contribution, due to the constructive interferences of light neutralino effects. The light neutralinos are typically the MSSM Bino like and the supersymmetric partner of U(1B−L gauge boson (B˜′-ino. We show that with universal soft supersymmetry breaking terms, the muon g−2 resides within 2σ of the measured value, namely ∼20×10−10, with Higgs mass equal to 125 GeV.
Non-SUSY Beyond Standard Model Searches: Recent Results from ATLAS and CMS
Malek, Fairouz; The ATLAS collaboration
2015-01-01
The Standard Model of particle physics is a sensational success, especially since the discovery of the 125 GeV Higgs boson. However, there are still numerous unanswered questions. Why is the Higgs so light? Do the interactions couplings unify and how can gravity be included? Why three fermion generations? What is dark matter? Theories Beyond the Standard Model (BSM), such as Grand Unified Theories, Extra Dimensions or Technicolour are trying to answer these questions. In this proceedings, we will focus on the most recent results obtained by the ATLAS and CMS experiments at the LHC for BSM searches, excluding Higgs and supersymmetry searches. New results on Dark matter, heavy narrow bosons, new heavy quarks and third generation leptoquarks are presented. A summary of the prospects at 14 TeV and at the High Luminosity LHC period is given.
R-broken SUSY Standard Model with right-handed neutrino
Gladyshev, A. V.; Parpalak, R. S.
2013-12-01
We consider the supersymmetric extension of the Standard Model with neutrino Yukawa interactions and R-parity violation. We found that R-parity breaking term λiνHuHd leads to an additional F-type contribution to the Higgs scalar potential, and thus to the masses of supersymmetric Higgs bosons. The most interesting consequence is the modification of the tree-level expression for the lightest neutral supersymmetric Higgs boson mass. It appears that due to this contribution the tree bound on the lightest Higgs mass may be shifted upwards, thus taking into account radiative corrections might open the part of the model parameter space consistent with the observation of the Higgs boson at LHC, which is not natural in the MSSM. We also calculate one-loop corrections to physical neutrino masses in case of neutrino-neutralino mixing and discuss the influence of this mass shift on parameter constraints.
Global fits of GUT-scale SUSY models with GAMBIT arXiv
Athron, Peter; Bringmann, Torsten; Buckley, Andy; Chrząszcz, Marcin; Conrad, Jan; Cornell, Jonathan M.; Dal, Lars A.; Edsjö, Joakim; Farmer, Ben; Jackson, Paul; Krislock, Abram; Kvellestad, Anders; Mahmoudi, Farvah; \\ Martinez, Gregory D.; Putze, Antje; Raklev, Are; Rogan, Christopher; Ruiz de Austri, Roberto; Saavedra, Aldo; Savage, Christopher; Scott, Pat; Serra, Nicola; Weniger, Christoph; White, Martin
We present the most comprehensive global fits to date of three supersymmetric models motivated by grand unification: the Constrained Minimal Supersymmetric Standard Model (CMSSM), and its Non-Universal Higgs Mass generalisations NUHM1 and NUHM2. We include likelihoods from a number of direct and indirect dark matter searches, a large collection of electroweak precision and flavour observables, direct searches for supersymmetry at LEP and Runs I and II of the LHC, and constraints from Higgs observables. Our analysis improves on existing results not only in terms of the number of included observables, but also in the level of detail with which we treat them, our sampling techniques for scanning the parameter space, and our treatment of nuisance parameters. We show that stau co-annihilation is now ruled out in the CMSSM at more than 95\\% confidence. Stop co-annihilation turns out to be one of the most promising mechanisms for achieving an appropriate relic density of dark matter in all three models, whilst avoid...
Energy Technology Data Exchange (ETDEWEB)
Jaffre, Michel; /Orsay, LAL
2012-02-01
The Tevatron collider has provided the CDF and D0 collaborations with large datasets as input to a rich program of physics beyond the standard model. The results presented here are from recent searches for SUSY particles using up to 6 fb{sup -1} of data. Supersymmetry (SUSY) [1] is one of the most favored theories beyond the standard model (SM). Each SM particle is associated to a sparticle whose spin differs by one half unit. This boson-fermion symmetry is obviously broken by some unknown mechanism. Even in the minimal supersymmetric extension of the SM (MSSM [2]) there are a large number of free parameters. To reduce this number one can introduce new assumptions on the symmetry breaking mechanism and build models based on minimal supergravity (as mSUGRA [3]) or on a Gauge Mediated Symmetry Breaking scenario (GMSB [4]), a top-down approach. Another possibility is to make phenomenological assumptions to reduce the number of particles accessible to the experiment while keeping some of the properties of the above models (bottom-up approach). As the sparticles are heavy, to produce them one has to make collisions at the highest center of mass energy. The Tevatron was the best place for discovery until the start of LHC. In the near term, Tevatron experiments and their large datasets remain competitive in areas like production of third generation squarks and of non-coloured sparticles. I will report on recent results from the CDF and D0 collaborations, assuming R-parity is conserved, i.e the sparticles are produced in pairs, and the lightest of them (LSP) is stable, neutral, weakly interacting, and detected as missing transverse energy, E{sub T}.
Latest news on SUSY from the ATLAS experiment
CERN. Geneva
2016-01-01
Despite the absence of experimental evidence, weak scale supersymmetry remains one of the best motivated and studied Standard Model extensions. This talk reports the latest ATLAS results for searches for supersymmetric (SUSY) particles, obtained with 13 to 18 fb-1 of 13 TeV data. Weak and strong production in both R-Parity conserving and R-Parity violating SUSY scenarios are considered. The searches involved final states including jets, missing transverse momentum, light leptons, taus or photons.
SUSY decays of Higgs particles
Djouadi, Abdelhak; Kalinowski, Jan; Zerwas, Peter M
1996-01-01
Among the possible decay modes of Higgs particles into supersymmetric states, neutralino and chargino decays play a prominent rôle. The experimental opportunities of observing such decay modes at LEP2 and at future $\\ee$ linear colliders are analyzed within the frame of the Minimal Supersymmetric extension of the Standard Model. For heavy Higgs particles, the chargino/neutralino decay modes can be very important, while only a small window is open for the lightest CP--even Higgs particle. If charginos/neutralinos are found at LEP2, such decay modes can be searched for in a small area of the parameter space, and invisible decays may reduce the exclusion limits of the lightest CP-even Higgs particle slightly; if charginos/neutralinos are not found at LEP2 in direct searches, the Higgs search will not be affected by the SUSY particle sector.
One-loop stabilization of the fuzzy four-sphere via softly broken SUSY
Energy Technology Data Exchange (ETDEWEB)
Steinacker, Harold C. [Faculty of Physics, University of Vienna,Boltzmanngasse 5, A-1090 Vienna (Austria)
2015-12-17
We describe a stabilization mechanism for fuzzy S{sub N}{sup 4} in the Euclidean IIB matrix model due to vacuum energy in the presence of a positive mass term. The one-loop effective potential for the radius contains an attractive contribution attributed to supergravity, while the mass term induces a repulsive contribution for small radius due to SUSY breaking. This leads to a stabilization of the radius. The mechanism should be pertinent to recent results on the genesis of 3+1-dimensional space-time in the Minkowskian IIB model.
Datta, Amitava
2017-10-01
The searches for supersymmetry at the Large Hadron Collider (LHC) have so far yielded only null results and have considerably tightened the bounds on the sparticle masses. This has generated some skepticism in the literature regarding the `naturalness of SUSY' which qualitatively requires some sparticles to be relatively light. Re-examining some of the bounds from LHC searches, it is argued with specific examples that the above skepticism is a red herring because (i) a quantitative and universally accepted definition of `naturalness' is not available and (ii) even if some conventional definitions of naturalness is accepted at their face values, the alleged tension with the apparently stringent LHC bounds wither away once the strong assumptions, by no means compelling, underlying such bounds are relaxed.
The SSM with Suppressed SUSY Charge
Directory of Open Access Journals (Sweden)
John A. Dixon
2016-10-01
Full Text Available The concept of Suppressed SUSY Charge, introduced in a recent Letter, is used here to assemble a new version of the SSM. This new SSM has no need for Squarks or Sleptons. It does not need spontaneous breaking of SUSY, so that the cosmological constant problem does not arise (at least at tree level. It mimics the usual non-supersymmetric Standard Model very well, and the absence of large flavour changing neutral currents is natural. There is no need for a hidden sector, or a messenger sector, or explicit ‘soft’ breaking of SUSY. Spontaneous Gauge Symmetry Breaking from SU(3×SU(2×U(1 to SU(3×U(1 in the model assembled here implies the existence of two new very heavy Higgs Bosons with mass 13.4 TeV, slightly smaller than the energy of the LHC at 14 TeV. There is also a curious set of Gauginos and Higgsinos which have exactly the same masses as the Higgs and Gauge Bosons. These do not couple to the Quarks and Leptons, except through the Higgs and Gauge Bosons. As it stands, this model probably gives rise to too many W+ decays to be consistent with experiment. The Feynman loop expansion of this theory also needs further examination.
Renormalizations in softly broken SUSY gauge theories
Avdeev, L. V.; Kazakov, D. I.; Kondrashuk, I. N.
1998-01-01
The supergraph technique for calculations in supersymmetric gauge theories where supersymmetry is broken in a "soft" way (without introducing quadratic divergencies) is reviewed. By introducing an external spurion field the set of Feynman rules is formulated and explicit connections between the UV counterterms of a softly broken and rigid SUSY theories are found. It is shown that the renormalization constants of softly broken SUSY gauge theory also become external superfields depending on the spurion field. Their explicit form repeats that of the constants of a rigid theory with the redefinition of the couplings. The method allows us to reproduce all known results on the renormalization of soft couplings and masses in a softly broken theory. As an example the renormalization group functions for soft couplings and masses in the Minimal Supersymmetric Standard Model up to the three-loop level are calculated.
Renormalizations in softly broken SUSY gauge theories
Energy Technology Data Exchange (ETDEWEB)
Avdeev, L.V.; Kazakov, D.I.; Kondrashuk, I.N. [Joint Inst. for Nuclear Research, Dubna (Russian Federation). Lab. of Theoretical Physics
1998-01-19
The supergraph technique for calculations in supersymmetric gauge theories where supersymmetry is broken in a ``soft`` way (without introducing quadratic divergencies) is reviewed. By introducing an external spurion field the set of Feynman rules is formulated and explicit connections between the UV counterterms of a softly broken and rigid SUSY theories are found. It is shown that the renormalization constants of softly broken SUSY gauge theory also become external superfields depending on the spurion field. Their explicit form repeats that of the constants of a rigid theory with the redefinition of the couplings. The method allows us to reproduce all known results on the renormalization of soft couplings and masses in a softly broken theory. As an example the renormalization group functions for soft couplings and masses in the minimal supersymmetric standard model up to the three-loop level are calculated. (orig.). 16 refs.
Susi astus rektori kohalt tagasi / Sigrid Laev
Laev, Sigrid
2003-01-01
Concordia rektor Mart Susi ja prorektor Mari-Ann Susi astusid kooli juhtimisest tagasi ja kuulutasid välja Concordia Varahalduse OÜ pankroti. Concordia töötajate loodud ühing hakkas looma uut õppeasutust
Papucci, Michele; Weiler, Andreas
2012-01-01
The first 1/fb of LHC searches have set impressive limits on new colored particles decaying to missing energy. We address the implication of these searches for naturalness in supersymmetry (SUSY). General bottom-up considerations of natural electroweak symmetry breaking show that higgsinos, stops, and the gluino should not be too far above the weak scale. The rest of the spectrum, including the squarks of the first two generations, can be heavier and beyond the current LHC reach. We have used collider simulations to determine the limits that all of the 1/fb searches pose on higgsinos, stops, and the gluino. We find that stops and the left-handed sbottom are starting to be constrained and must be heavier than about 200-300 GeV when decaying to higgsinos. The gluino must be heavier than about 600-800 GeV when it decays to stops and sbottoms. While these findings point toward scenarios with a lighter third generation split from the other squarks, we do find that moderately-tuned regions remain, where the gluino ...
On inflation, cosmological constant, and SUSY breaking
Energy Technology Data Exchange (ETDEWEB)
Linde, Andrei [Department of Physics and SITP, Stanford University, Stanford, California 94305 (United States)
2016-11-02
We consider a broad class of inflationary models of two unconstrained chiral superfields, the stabilizer S and the inflaton Φ, which can describe inflationary models with nearly arbitrary potentials. These models include, in particular, the recently introduced theories of cosmological attractors, which provide an excellent fit to the latest Planck data. We show that by adding to the superpotential of the fields S and Φ a small term depending on a nilpotent chiral superfield P one can break SUSY and introduce a small cosmological constant without affecting main predictions of the original inflationary scenario.
Search for SUSY trilepton events with ATLAS at the LHC
Energy Technology Data Exchange (ETDEWEB)
Serfon, C.; Kummer, C. [Ludwig-Maximilians Univ. Muenchen, Garching b. Muenchen (Germany)
2007-07-01
One of the best motivated extension of the Standard Model is SUper-SYmmetry (SUSY). The ATLAS experiment at the pp-collider LHC will search for the new particles predicted by SUSY. In this talk, the discovery potential of the direct production of charginos and neutralinos decaying into a final state with three charged leptons is presented. In the start-up phase of the LHC an important signal of SUSY, the missing transverse energy, will need extensive calibration studies. We therefore present an analysis which does not rely on this signature. The model used for the analysis is mSUGRA. A full simulation of the ATLS detector has been used, and the most important backgrounds tt, W{sup {+-}} Z and ZZ have been taken into account. (orig.)
Overview of SUSY results from the ATLAS experiment
Federico Brazzale Simone
2014-01-01
The search for Supersymmetric extensions of the Standard Model (SUSY) remains a hot topic in high energy phisycs in the light of the discovery of the Higgs boson with mass of 125 GeV. Supersymmetric particles can cancel out the quadratically-divergent loop corrections to the Higgs boson mass and can explain presence of Dark Matter in the Universe. Moreover, SUSY can unify the gauge couplings of the Standard Model at high energy scales. Under certain theoretical assumptions, some of the super-...
Flavor violating Z′ from SO(10 SUSY GUT in High-Scale SUSY
Directory of Open Access Journals (Sweden)
Junji Hisano
2015-05-01
Full Text Available We propose an SO(10 supersymmetric grand unified theory (SUSY GUT, where the SO(10 gauge symmetry breaks down to SU(3c×SU(2L×U(1Y×U(1X at the GUT scale and U(1X is radiatively broken at the SUSY-braking scale. In order to achieve the observed Higgs mass around 126 GeV and also to satisfy constraints on flavor- and/or CP-violating processes, we assume that the SUSY-breaking scale is O(100 TeV, so that the U(1X breaking scale is also O(100 TeV. One big issue in the SO(10 GUTs is how to realize realistic Yukawa couplings. In our model, not only 16-dimensional but also 10-dimensional matter fields are introduced to predict the observed fermion masses and mixings. The Standard-Model quarks and leptons are linear combinations of the 16- and 10-dimensional fields so that the U(1X gauge interaction may be flavor-violating. We investigate the current constraints on the flavor-violating Z′ interaction from the flavor physics and discuss prospects for future experiments.
Hitting sbottom in natural SUSY
Lee, Hyun Min; Trott, Michael
2012-01-01
We compare the experimental prospects of direct stop and sbottom pair production searches at the LHC. Such searches for stops are of great interest as they directly probe for states that are motivated by the SUSY solution to the hierarchy problem of the Higgs mass parameter - leading to a "Natural" SUSY spectrum. Noting that sbottom searches are less experimentally challenging and scale up in reach directly with the improvement on b-tagging algorithms, we discuss the interplay of small TeV scale custodial symmetry violation with sbottom direct pair production searches as a path to obtaining strong sub-TeV constraints on stops in a natural SUSY scenario. We argue that if a weak scale natural SUSY spectrum does not exist within the reach of LHC, then hopes for such a spectrum for large regions of parameter space should sbottom out. Conversely, the same arguments make clear that a discovery of such a spectrum is likely to proceed in a sbottom up manner.
Modeling and Simulation of Matrix Converter
DEFF Research Database (Denmark)
Liu, Fu-rong; Klumpner, Christian; Blaabjerg, Frede
2005-01-01
This paper discusses the modeling and simulation of matrix converter. Two models of matrix converter are presented: one is based on indirect space vector modulation and the other is based on power balance equation. The basis of these two models is• given and the process on modeling is introduced...
Using Experimental Data To Test And Improve Susy Theories
Wang, T
2004-01-01
There are several pieces of evidence that our world is described by a supersymmetric extension of the Standard Model. In this thesis, I assume this is the case and study how to use experimental data to test and improve supersymmetric standard models. Several experimental signatures and their implications are covered in this thesis: the result of the branching ratio of b → sγ is used to put constraints on SUSY models; the measured time-dependent CP asymmetry in the B → &phis;KS process is used to test unification scale models; the excess of positrons from cosmic rays helps us to test the property of the Lightest Supersymmetric Particle and the Cold Dark Matter production mechanisms; the LEP higgs search results are used to classify SUSY models; SUSY signatures at the Tevatron are used to distinguish different unification scale models; by considering the μ problem, SUSY theories are improved. Due to the large unknown parameter space, all of the above inputs should be used ...
Post LHC7 SUSY benchmark points for ILC physics
Energy Technology Data Exchange (ETDEWEB)
Baer, Howard [Oklahoma Univ., Norman, OK (United States); List, Jenny [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)
2012-05-15
We re-evaluate prospects for supersymmetry at the proposed International Linear e{sup +}e{sup -} Collider (ILC) in light of the first year of serious data taking at LHC with {radical}(s)=7 TeV and {proportional_to}5 fb{sup -1} of pp collisions (LHC7). Strong new limits from LHC SUSY searches, along with a hint of a Higgs boson signal around m{sub h}{proportional_to}125 GeV, suggest a paradigm shift from previously popular models to ones with new and compelling signatures. We present a variety of new ILC benchmark models, including: natural SUSY, hidden SUSY, NUHM2 with low m{sub A}, non-universal gaugino mass (NUGM) model, pMSSM, Kallosh-Linde model, Bruemmer-Buchmueller model, normal scalar mass hierarchy (NMH) plus one surviving case from mSUGRA/CMSSM in the far focus point region. While all these models at present elude the latest LHC limits, they do offer intriguing case study possibilities for ILC operating at {radical}(s){proportional_to}0.25-1 TeV, and present a view of some of the diverse SUSY phenomena which might be expected at both LHC and ILC in the post LHC7 era.
The Higgs boson mass and SUSY spectra in 10D SYM theory with magnetized extra dimensions
Directory of Open Access Journals (Sweden)
Hiroyuki Abe
2014-11-01
Full Text Available We study the Higgs boson mass and the spectrum of supersymmetric (SUSY particles in the well-motivated particle physics model derived from a ten-dimensional supersymmetric Yang–Mills theory compactified on three factorizable tori with magnetic fluxes. This model was proposed in a previous work, where the flavor structures of the standard model including the realistic Yukawa hierarchies are obtained from non-hierarchical input parameters on the magnetized background. Assuming moduli- and anomaly-mediated contributions dominate the soft SUSY breaking terms, we study the precise SUSY spectra and analyze the Higgs boson mass in this mode, which are compared with the latest experimental data.
Matrix model description of baryonic deformations
Energy Technology Data Exchange (ETDEWEB)
Bena, Iosif; Murayama, Hitoshi; Roiban, Radu; Tatar, Radu
2003-03-13
We investigate supersymmetric QCD with N{sub c} + 1 flavors using an extension of the recently proposed relation between gauge theories and matrix models.The impressive agreement between the two sides provides a beautiful confirmation of the extension of the gauge theory-matrix model relation to this case.
Status of SUSY searches at the LHC (including SUSY Higgs bosons)
Marshall, Zach; The ATLAS collaboration
2017-01-01
We review the status of SUSY searches at the LHC, including searches for SUSY Higgs Bosons. ATLAS and CMS have both prepared a large number of search results on the full 2015+2016 dataset, pushing the bounds on SUSY further than ever before.
Post LHC8 SUSY benchmark points for ILC physics
Energy Technology Data Exchange (ETDEWEB)
Baer, Howard [Oklahoma Univ., Norman, OK (United States); List, Jenny [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)
2013-07-15
We re-evaluate prospects for supersymmetry at the proposed International Linear e{sup +}e{sup -} Collider (ILC) in light of the first two years of serious data taking at LHC: LHC7 with {proportional_to}5 fb{sup -1} of pp collisions at {radical}(s)=7 TeV and LHC8 with {proportional_to}20 fb{sup -1} at {radical}(s)=8 TeV. Strong new limits from LHC8 SUSY searches, along with the discovery of a Higgs boson with m{sub h}{approx_equal}125 GeV, suggest a paradigm shift from previously popular models to ones with new and compelling signatures. After a review of the current status of supersymmetry, we present a variety of new ILC benchmark models, including: natural SUSY, radiatively-driven natural SUSY (RNS), NUHM2 with low m{sub A}, a focus point case from mSUGRA/CMSSM, non-universal gaugino mass (NUGM) model, {tau}-coannihilation, Kallosh-Linde/spread SUSY model, mixed gauge-gravity mediation, normal scalar mass hierarchy (NMH), and one example with the recently discovered Higgs boson being the heavy CP-even state H. While all these models at present elude the latest LHC8 limits, they do offer intriguing case study possibilities for ILC operating at {radical}(s){approx_equal} 0.25-1 TeV. The benchmark points also present a view of the widely diverse SUSY phenomena which might still be expected in the post LHC8 era at both LHC and ILC.
Risk matrix model for rotating equipment
Directory of Open Access Journals (Sweden)
Wassan Rano Khan
2014-07-01
Full Text Available Different industries have various residual risk levels for their rotating equipment. Accordingly the occurrence rate of the failures and associated failure consequences categories are different. Thus, a generalized risk matrix model is developed in this study which can fit various available risk matrix standards. This generalized risk matrix will be helpful to develop new risk matrix, to fit the required risk assessment scenario for rotating equipment. Power generation system was taken as case study. It was observed that eight subsystems were under risk. Only vibration monitor system was under high risk category, while remaining seven subsystems were under serious and medium risk categories.
Partial chord diagrams and matrix models
DEFF Research Database (Denmark)
Andersen, Jørgen Ellegaard; Fuji, Hiroyuki; Manabe, Masahide
spectrum. Furthermore, we consider the boundary length and point spectrum that unifies the last two types of spectra. We introduce matrix models that encode generating functions of partial chord diagrams filtered by each of these spectra. Using these matrix models, we derive partial differential equations......In this article, the enumeration of partial chord diagrams is discussed via matrix model techniques. In addition to the basic data such as the number of backbones and chords, we also consider the Euler characteristic, the backbone spectrum, the boundary point spectrum, and the boundary length...
Micromechanical Modeling of Woven Metal Matrix Composites
Bednarcyk, Brett A.; Pindera, Marek-Jerzy
1997-01-01
This report presents the results of an extensive micromechanical modeling effort for woven metal matrix composites. The model is employed to predict the mechanical response of 8-harness (8H) satin weave carbon/copper (C/Cu) composites. Experimental mechanical results for this novel high thermal conductivity material were recently reported by Bednarcyk et al. along with preliminary model results. The micromechanics model developed herein is based on an embedded approach. A micromechanics model for the local (micro-scale) behavior of the woven composite, the original method of cells (Aboudi), is embedded in a global (macro-scale) micromechanics model (the three-dimensional generalized method of cells (GMC-3D) (Aboudi). This approach allows representation of true repeating unit cells for woven metal matrix composites via GMC-3D, and representation of local effects, such as matrix plasticity, yarn porosity, and imperfect fiber-matrix bonding. In addition, the equations of GMC-3D were reformulated to significantly reduce the number of unknown quantities that characterize the deformation fields at the microlevel in order to make possible the analysis of actual microstructures of woven composites. The resulting micromechanical model (WCGMC) provides an intermediate level of geometric representation, versatility, and computational efficiency with respect to previous analytical and numerical models for woven composites, but surpasses all previous modeling work by allowing the mechanical response of a woven metal matrix composite, with an elastoplastic matrix, to be examined for the first time. WCGMC is employed to examine the effects of composite microstructure, porosity, residual stresses, and imperfect fiber-matrix bonding on the predicted mechanical response of 8H satin C/Cu. The previously reported experimental results are summarized, and the model predictions are compared to monotonic and cyclic tensile and shear test data. By considering appropriate levels of porosity
Mart Susi tegevust uurib keskkriminaalpolitsei / Sigrid Laev
Laev, Sigrid
2003-01-01
Keskkriminaalpolitsei algatas Concordia ülikooliga seotu uurimiseks kaks kriminaalasja, millest üks käsitleb endise rektori Mart Susi ja endise prorektori Mari-Ann Susi võimalikku ametiseisundi kuritarvitamist, teise sisuks on Concordia varade ilmne varjamine
A 125 GeV Higgs and Its Diphoton Signal in Different SUSY Models: A Mini Review
Directory of Open Access Journals (Sweden)
Zhaoxia Heng
2012-01-01
Full Text Available In this paper we briefly review our recent studies on a 125 GeV Higgs and its diphoton signal rate in different low-energy supersymmetric models, namely, the minimal supersymmetric standard model (MSSM, the next-to-minimal supersymmetric standard model (NMSSM, the nearly minimal supersymmetric standard model (nMSSM, and the constrained MSSM. Our conclusion is as follows (i in the allowed parameter space the SM-like Higgs boson can easily be 125 GeV in the MSSM, NMSSM, and nMSSM, while it is hard to realize in the constrained MSSM; (ii the diphoton Higgs signal rate in the nMSSM and constrained MSSM is suppressed relative to the prediction of the SM, while the signal rate can be enhanced in the MSSM and NMSSM; (iii the NMSSM may allow for a lighter top squark than the MSSM, which can thus ameliorate the fine-tuning problem.
Supersymmetric SYK model and random matrix theory
Li, Tianlin; Liu, Junyu; Xin, Yuan; Zhou, Yehao
2017-06-01
In this paper, we investigate the effect of supersymmetry on the symmetry classification of random matrix theory ensembles. We mainly consider the random matrix behaviors in the N=1 supersymmetric generalization of Sachdev-Ye-Kitaev (SYK) model, a toy model for two-dimensional quantum black hole with supersymmetric constraint. Some analytical arguments and numerical results are given to show that the statistics of the supersymmetric SYK model could be interpreted as random matrix theory ensembles, with a different eight-fold classification from the original SYK model and some new features. The time-dependent evolution of the spectral form factor is also investigated, where predictions from random matrix theory are governing the late time behavior of the chaotic hamiltonian with supersymmetry.
Matrix model formulation of four dimensional gravity
Energy Technology Data Exchange (ETDEWEB)
De Pietri, Roberto
2001-03-01
The attempt of extending to higher dimensions the matrix model formulation of two-dimensional quantum gravity leads to the consideration of higher rank tensor models. We discuss how these models relate to four dimensional quantum gravity and the precise conditions allowing to associate a four-dimensional simplicial manifold to Feynman diagrams of a rank-four tensor model.
Non-susy exotics searches at the Tevatron
Energy Technology Data Exchange (ETDEWEB)
Pronko, Alexandre; /Fermilab
2008-05-01
The authors present results of searches for signs of physics beyond the Standard Model. The focus of this paper is on analyses not driven by SUSY models. Most of the presented results are based on {approx} 2 fb{sup -1} of data and obtained since summer of 2007. No significant excess of data over predicted background is observed. They report kinematic distributions, data and background counts, as well as limits on some parameters of selected models of new physics.
A matrix model from string field theory
Directory of Open Access Journals (Sweden)
Syoji Zeze
2016-09-01
Full Text Available We demonstrate that a Hermitian matrix model can be derived from level truncated open string field theory with Chan-Paton factors. The Hermitian matrix is coupled with a scalar and U(N vectors which are responsible for the D-brane at the tachyon vacuum. Effective potential for the scalar is evaluated both for finite and large N. Increase of potential height is observed in both cases. The large $N$ matrix integral is identified with a system of N ZZ branes and a ghost FZZT brane.
Supersymmetric grand unified theories from quarks to strings via SUSY GUTs
Raby, Stuart
2017-01-01
These course-tested lectures provide a technical introduction to Supersymmetric Grand Unified Theories (SUSY GUTs), as well as a personal view on the topic by one of the pioneers in the field. While the Standard Model of Particle Physics is incredibly successful in describing the known universe it is, nevertheless, an incomplete theory with many free parameters and open issues. An elegant solution to all of these quandaries is the proposed theory of SUSY GUTs. In a GUT, quarks and leptons are related in a simple way by the unifying symmetry and their electric charges are quantized, further the relative strength of the strong, weak and electromagnetic forces are predicted. SUSY GUTs additionally provide a framework for understanding particle masses and offer candidates for dark matter. Finally, with the extension of SUSY GUTs to string theory, a quantum-mechanically consistent unification of the four known forces (including gravity) is obtained. The book is organized in three sections: the first section contai...
Cornering natural SUSY at LHC Run II and beyond
Buckley, Matthew R.; Feld, David; Macaluso, Sebastian; Monteux, Angelo; Shih, David
2017-08-01
We derive the latest constraints on various simplified models of natural SUSY with light higgsinos, stops and gluinos, using a detailed and comprehensive reinterpretation of the most recent 13 TeV ATLAS and CMS searches with ˜ 15 fb-1 of data. We discuss the implications of these constraints for fine-tuning of the electroweak scale. While the most "vanilla" version of SUSY (the MSSM with R-parity and flavor-degenerate sfermions) with 10% fine-tuning is ruled out by the current constraints, models with decoupled valence squarks or reduced missing energy can still be fully natural. However, in all of these models, the mediation scale must be extremely low ( motivated by this work.
Matrix Tricks for Linear Statistical Models
Puntanen, Simo; Styan, George PH
2011-01-01
In teaching linear statistical models to first-year graduate students or to final-year undergraduate students there is no way to proceed smoothly without matrices and related concepts of linear algebra; their use is really essential. Our experience is that making some particular matrix tricks very familiar to students can substantially increase their insight into linear statistical models (and also multivariate statistical analysis). In matrix algebra, there are handy, sometimes even very simple "tricks" which simplify and clarify the treatment of a problem - both for the student and
Hermitian Matrix Model with Plaquette Interaction
DEFF Research Database (Denmark)
Chekhov, L.; Kristjansen, C.
1996-01-01
We study a hermitian $(n+1)$-matrix model with plaquette interaction, $\\sum_{i=1}^n MA_iMA_i$. By means of a conformal transformation we rewrite the model as an $O(n)$ model on a random lattice with a non polynomial potential. This allows us to solve the model exactly. We investigate the critical...... properties of the plaquette model and find that for $n\\in]-2,2]$ the model belongs to the same universality class as the $O(n)$ model on a random lattice....
Random matrix model for disordered conductors
Indian Academy of Sciences (India)
1. Introduction. Matrix models are being successfully employed in a variety of domains of physics includ- ing studies on heavy nuclei [1], mesoscopic disordered conductors [2,3], two-dimensional quantum gravity [4], and chaotic quantum systems [5]. Universal conductance fluctuations in metals [6] and spectral fluctuations in ...
Random matrix model for disordered conductors
Indian Academy of Sciences (India)
Keywords. Disordered conductors; random matrix theory; Dyson's Coulomb gas model. ... An interesting random walk problem associated with the joint probability distribution of the ensuing ensemble is discussed and its connection with level dynamics is brought out. It is further proved that Dyson's Coulomb gas analogy ...
Early SUSY Searches at the CMS Experiment at CERN
Kasieczka, Gregor
When the Large Hadron Collider (LHC) commences operation, physicists all over the world will be eagerly awaiting data. The LHC was built as a discovery machine and the two general purpose detectors ATLAS and CMS might see evidence for new ndings with the rst year of data. Among the possible early discoveries is supersymmetry or SUSY. For SUSY events there exist irreducible backgrounds - Standard Model processes that are in principle indistinguishable from the signal. A possible search channel for SUSY are events with jets + one lepton + large missing transverse energy or 6ET . In this channel there also exists a signi cant contribution of Standard Model top anti-top production. For early data the prediction of the background overshadowing the expected supersymmetric events by computer simulations is subject to large uncertainties. It is necessary to use strategies that estimate the background in the signal region by using information from regions that are expected to be signal-free. The work examines such tec...
Conciliating SUSY with the Z-peaked excess
Directory of Open Access Journals (Sweden)
Mitsou Vasiliki A.
2016-01-01
Full Text Available The ATLAS experiment observed an excess at the 3σ level in the channel of Z boson, jets and high missing transverse momentum in the full 2012 dataset at 8 TeV while searching for SUSY. The question arises whether the abundance and the kinematical features of this excess are compatible with the yet unconstrained supersymmetric realm, respecting at the same time the measured Higgs boson properties and dark matter density. By trying to explain this signal with SUSY we find that only relatively light gluinos together with a heavy neutralino NLSP decaying predominantly to a Z boson plus a light gravitino could reproduce the excess. We construct an explicit general gauge mediation model able to match the observed signal. More sophisticated models could also reproduce the signal, as long as it features light gluinos, or heavy particles with a strong production cross section, producing at least one Z boson in its decay chain. The implications of our findings for the Run II at LHC with the scaling on the Z peak, as well as for the direct search of gluinos and other SUSY particles, are also discussed.
The BSM-AI project: SUSY-AI-generalizing LHC limits on supersymmetry with machine learning.
Caron, Sascha; Kim, Jong Soo; Rolbiecki, Krzysztof; de Austri, Roberto Ruiz; Stienen, Bob
2017-01-01
A key research question at the Large Hadron Collider is the test of models of new physics. Testing if a particular parameter set of such a model is excluded by LHC data is a challenge: it requires time consuming generation of scattering events, simulation of the detector response, event reconstruction, cross section calculations and analysis code to test against several hundred signal regions defined by the ATLAS and CMS experiments. In the BSM-AI project we approach this challenge with a new idea. A machine learning tool is devised to predict within a fraction of a millisecond if a model is excluded or not directly from the model parameters. A first example is SUSY-AI, trained on the phenomenological supersymmetric standard model (pMSSM). About 300, 000 pMSSM model sets - each tested against 200 signal regions by ATLAS - have been used to train and validate SUSY-AI. The code is currently able to reproduce the ATLAS exclusion regions in 19 dimensions with an accuracy of at least [Formula: see text]. It has been validated further within the constrained MSSM and the minimal natural supersymmetric model, again showing high accuracy. SUSY-AI and its future BSM derivatives will help to solve the problem of recasting LHC results for any model of new physics. SUSY-AI can be downloaded from http://susyai.hepforge.org/. An on-line interface to the program for quick testing purposes can be found at http://www.susy-ai.org/.
The BSM-AI project: SUSY-AI-generalizing LHC limits on supersymmetry with machine learning
Energy Technology Data Exchange (ETDEWEB)
Caron, Sascha [Radboud Universiteit, Institute for Mathematics, Astro- and Particle Physics IMAPP, Nijmegen (Netherlands); Nikhef, Amsterdam (Netherlands); Kim, Jong Soo [UAM/CSIC, Instituto de Fisica Teorica, Madrid (Spain); Rolbiecki, Krzysztof [UAM/CSIC, Instituto de Fisica Teorica, Madrid (Spain); University of Warsaw, Faculty of Physics, Warsaw (Poland); Ruiz de Austri, Roberto [IFIC-UV/CSIC, Instituto de Fisica Corpuscular, Valencia (Spain); Stienen, Bob [Radboud Universiteit, Institute for Mathematics, Astro- and Particle Physics IMAPP, Nijmegen (Netherlands)
2017-04-15
A key research question at the Large Hadron Collider is the test of models of new physics. Testing if a particular parameter set of such a model is excluded by LHC data is a challenge: it requires time consuming generation of scattering events, simulation of the detector response, event reconstruction, cross section calculations and analysis code to test against several hundred signal regions defined by the ATLAS and CMS experiments. In the BSM-AI project we approach this challenge with a new idea. A machine learning tool is devised to predict within a fraction of a millisecond if a model is excluded or not directly from the model parameters. A first example is SUSY-AI, trained on the phenomenological supersymmetric standard model (pMSSM). About 300, 000 pMSSM model sets - each tested against 200 signal regions by ATLAS - have been used to train and validate SUSY-AI. The code is currently able to reproduce the ATLAS exclusion regions in 19 dimensions with an accuracy of at least 93%. It has been validated further within the constrained MSSM and the minimal natural supersymmetric model, again showing high accuracy. SUSY-AI and its future BSM derivatives will help to solve the problem of recasting LHC results for any model of new physics. SUSY-AI can be downloaded from http://susyai.hepforge.org/. An on-line interface to the program for quick testing purposes can be found at http://www.susy-ai.org/. (orig.)
The BSM-AI project: SUSY-AI-generalizing LHC limits on supersymmetry with machine learning
Caron, Sascha; Kim, Jong Soo; Rolbiecki, Krzysztof; de Austri, Roberto Ruiz; Stienen, Bob
2017-04-01
A key research question at the Large Hadron Collider is the test of models of new physics. Testing if a particular parameter set of such a model is excluded by LHC data is a challenge: it requires time consuming generation of scattering events, simulation of the detector response, event reconstruction, cross section calculations and analysis code to test against several hundred signal regions defined by the ATLAS and CMS experiments. In the BSM-AI project we approach this challenge with a new idea. A machine learning tool is devised to predict within a fraction of a millisecond if a model is excluded or not directly from the model parameters. A first example is SUSY-AI, trained on the phenomenological supersymmetric standard model (pMSSM). About 300, 000 pMSSM model sets - each tested against 200 signal regions by ATLAS - have been used to train and validate SUSY-AI. The code is currently able to reproduce the ATLAS exclusion regions in 19 dimensions with an accuracy of at least 93%. It has been validated further within the constrained MSSM and the minimal natural supersymmetric model, again showing high accuracy. SUSY-AI and its future BSM derivatives will help to solve the problem of recasting LHC results for any model of new physics. SUSY-AI can be downloaded from http://susyai.hepforge.org/. An on-line interface to the program for quick testing purposes can be found at http://www.susy-ai.org/.
Precision natural SUSY at CEPC, FCC-ee, and ILC
Energy Technology Data Exchange (ETDEWEB)
Fan, JiJi [Department of Physics, Syracuse University,Syracuse, NY, 13210 (United States); Reece, Matthew [Department of Physics, Harvard University,Cambridge, MA 02138 (United States); Wang, Lian-Tao [Enrico Fermi Institute and Kavli Institute for Cosmological Physics, University of Chicago,Chicago, IL 60637 (United States)
2015-08-31
Testing the idea of naturalness is and will continue to be one of the most important goals of high energy physics experiments. It will play a central role in the physics program of future colliders. In this paper, we present projections of the reach of natural SUSY at future lepton colliders: CEPC, FCC-ee and ILC. We focus on the observables which give the strongest reach, the electroweak precision observables (for left-handed stops), and Higgs to gluon and photon decay rates (for both left- and right-handed stops). There is a “blind spot” when the stop mixing parameter X{sub t} is approximately equal to the average stop mass. We argue that in natural scenarios, bounds on the heavy Higgs bosons from tree-level mixing effects that modify the hbb̄ coupling together with bounds from b→sγ play a complementary role in probing the blind spot region. For specific natural SUSY scenarios such as folded SUSY in which the top partners do not carry Standard Model color charges, electroweak precision observables could be the most sensitive probe. In all the scenarios discussed in this paper, the combined set of precision measurements will probe down to a few percent in fine-tuning.
Matrix Factorizations, Minimal Models and Massey Products
Knapp, J; Knapp, Johanna; Omer, Harun
2006-01-01
We present a method to compute the full non-linear deformations of matrix factorizations for ADE minimal models. This method is based on the calculation of higher products in the cohomology, called Massey products. The algorithm yields a polynomial ring whose vanishing relations encode the obstructions of the deformations of the D-branes characterized by these matrix factorizations. This coincides with the critical locus of the effective superpotential which can be computed by integrating these relations. Our results for the effective superpotential are in agreement with those obtained from solving the A-infinity relations. We point out a relation to the superpotentials of Kazama-Suzuki models. We will illustrate our findings by various examples, putting emphasis on the E_6 minimal model.
Transmission line matrix model for ultrasonic imaging
Ciocan, Razvan; Ida, Nathan; Driscoll, Diana
2002-06-01
A transmission-line matrix (TLM) model was developed to simulate the ultrasound propagation in the multi-layer structures. The spatial resolution of the proposed model is better than tenth wavelength. The numerical modeling is carried-out for frequencies that are usually used in ultrasound imagery (3.5 - 25MHz). The acoustic impedance profile of multi-layer structures considered are similar to those found in nondestructive evaluation and in medical imaging. The structures modeled are: brazed joints, stomach and colon walls. Structures with artificial flaws are also modeled. A comparison between real images and numerical generated ones is provided for each considered structure. Both frequency and time domain responses are obtained from the structures under investigation. Both single and array transducer techniques are modeled and their performances are evaluated for the proposed structures. Different shapes for the incident pulse are considered in numerically generated images.
Perturbation analysis of nonlinear matrix population models
Directory of Open Access Journals (Sweden)
Hal Caswell
2008-03-01
Full Text Available Perturbation analysis examines the response of a model to changes in its parameters. It is commonly applied to population growth rates calculated from linear models, but there has been no general approach to the analysis of nonlinear models. Nonlinearities in demographic models may arise due to density-dependence, frequency-dependence (in 2-sex models, feedback through the environment or the economy, and recruitment subsidy due to immigration, or from the scaling inherent in calculations of proportional population structure. This paper uses matrix calculus to derive the sensitivity and elasticity of equilibria, cycles, ratios (e.g. dependency ratios, age averages and variances, temporal averages and variances, life expectancies, and population growth rates, for both age-classified and stage-classified models. Examples are presented, applying the results to both human and non-human populations.
Mirror of the refined topological vertex from a matrix model
Eynard, B
2011-01-01
We find an explicit matrix model computing the refined topological vertex, starting from its representation in terms of plane partitions. We then find the spectral curve of that matrix model, and thus the mirror symmetry of the refined vertex. With the same method we also find a matrix model for the strip geometry, and we find its mirror curve. The fact that there is a matrix model shows that the refined topological string amplitudes also satisfy the remodeling the B-model construction.
Search for SUSY in the AMSB scenario with the DELPHI detector
Abdallah, J.; Adam, W.; Adzic, P.; Albrecht, T.; Alderweireld, T.; Alemany-Fernandez, R.; Allmendinger, T.; Allport, P.P.; Amaldi, U.; Amapane, N.; Amato, S.; Anashkin, E.; Andreazza, A.; Andringa, S.; Anjos, N.; Antilogus, P.; Apel, W.D.; Arnoud, Y.; Ask, S.; Asman, B.; Augustin, J.E.; Augustinus, A.; Baillon, P.; Ballestrero, A.; Bambade, P.; Barbier, R.; Bardin, D.; Barker, G.; Baroncelli, A.; Battaglia, M.; Baubillier, M.; Becks, K.H.; Begalli, M.; Behrmann, A.; Ben-Haim, E.; Benekos, N.; Benvenuti, A.; Berat, C.; Berggren, M.; Berntzon, L.; Bertrand, D.; Besancon, M.; Besson, N.; Bloch, D.; Blom, M.; Bluj, M.; Bonesini, M.; Boonekamp, M.; Booth, P.S.L.; Borisov, G.; Botner, O.; Bouquet, B.; Bowcock, T.J.V.; Boyko, I.; Bracko, M.; Brenner, R.; Brodet, E.; Bruckman, P.; Brunet, J.M.; Bugge, L.; Buschmann, P.; Calvi, M.; Camporesi, T.; Canale, V.; Carena, F.; Castro, Nuno Filipe; Cavallo, F.; Chapkin, M.; Charpentier, Ph.; Checchia, P.; Chierici, R.; Chliapnikov, P.; Chudoba, J.; Chung, S.U.; Cieslik, K.; Collins, P.; Contri, R.; Cosme, G.; Cossutti, F.; Costa, M.J.; Crennell, D.; Cuevas, J.; D'Hondt, J.; Dalmau, J.; da Silva, T.; Da Silva, W.; Della Ricca, G.; De Angelis, A.; De Boer, W.; De Clercq, C.; De Lotto, B.; De Maria, N.; De Min, A.; de Paula, L.; Di Ciaccio, L.; Di Simone, A.; Doroba, K.; Drees, J.; Dris, M.; Eigen, G.; Ekelof, T.; Ellert, M.; Elsing, M.; Espirito Santo, M.C.; Fanourakis, G.; Fassouliotis, D.; Feindt, M.; Fernandez, J.; Ferrer, A.; Ferro, F.; Flagmeyer, U.; Foeth, H.; Fokitis, E.; Fulda-Quenzer, F.; Fuster, J.; Gandelman, M.; Garcia, C.; Gavillet, Ph.; Gazis, Evangelos; Gokieli, R.; Golob, B.; Gomez-Ceballos, G.; Goncalves, P.; Graziani, E.; Grosdidier, G.; Grzelak, K.; Guy, J.; Haag, C.; Hallgren, A.; Hamacher, K.; Hamilton, K.; Haug, S.; Hauler, F.; Hedberg, V.; Hennecke, M.; Herr, H.; Hoffman, J.; Holmgren, S.O.; Holt, P.J.; Houlden, M.A.; Hultqvist, K.; Jackson, John Neil; Jarlskog, G.; Jarry, P.; Jeans, D.; Johansson, Erik Karl; Johansson, P.D.; Jonsson, P.; Joram, C.; Jungermann, L.; Kapusta, Frederic; Katsanevas, S.; Katsoufis, E.; Kernel, G.; Kersevan, B.P.; Kerzel, U.; Kiiskinen, A.; King, B.T.; Kjaer, N.J.; Kluit, P.; Kokkinias, P.; Kourkoumelis, C.; Kouznetsov, O.; Krumstein, Z.; Kucharczyk, M.; Lamsa, J.; Leder, G.; Ledroit, Fabienne; Leinonen, L.; Leitner, R.; Lemonne, J.; Lepeltier, V.; Lesiak, T.; Liebig, W.; Liko, D.; Lipniacka, A.; Lopes, J.H.; Lopez, J.M.; Loukas, D.; Lutz, P.; Lyons, L.; MacNaughton, J.; Malek, A.; Maltezos, S.; Mandl, F.; Marco, J.; Marco, R.; Marechal, B.; Margoni, M.; Marin, J.C.; Mariotti, C.; Markou, A.; Martinez-Rivero, C.; Masik, J.; Mastroyiannopoulos, N.; Matorras, F.; Matteuzzi, C.; Mazzucato, F.; Mazzucato, M.; McNulty, R.; Meroni, C.; Migliore, E.; Mitaroff, W.; Mjoernmark, U.; Moa, T.; Moch, M.; Monig, Klaus; Monge, R.; Montenegro, J.; Moraes, D.; Moreno, S.; Morettini, P.; Mueller, U.; Muenich, K.; Mulders, M.; Mundim, L.; Murray, W.; Muryn, B.; Myatt, G.; Myklebust, T.; Nassiakou, M.; Navarria, F.; Nawrocki, K.; Nicolaidou, R.; Nikolenko, M.; Oblakowska-Mucha, A.; Obraztsov, V.; Olshevski, A.; Onofre, A.; Orava, R.; Osterberg, K.; Ouraou, A.; Oyanguren, A.; Paganoni, M.; Paiano, S.; Palacios, J.P.; Palka, H.; Papadopoulou, Th.D.; Pape, L.; Parkes, C.; Parodi, F.; Parzefall, U.; Passeri, A.; Passon, O.; Peralta, L.; Perepelitsa, V.; Perrotta, A.; Petrolini, A.; Piedra, J.; Pieri, L.; Pierre, F.; Pimenta, M.; Piotto, E.; Podobnik, T.; Poireau, V.; Pol, M.E.; Polok, G.; Poropat, P.; Pozdniakov, V.; Pukhaeva, N.; Pullia, A.; Rames, J.; Ramler, L.; Read, Alexander L.; Rebecchi, P.; Rehn, J.; Reid, D.; Reinhardt, R.; Renton, P.; Richard, F.; Ridky, J.; Rivero, M.; Rodriguez, D.; Romero, A.; Ronchese, P.; Roudeau, P.; Rovelli, T.; Ruhlmann-Kleider, V.; Ryabtchikov, D.; Sadovsky, A.; Salmi, L.; Salt, J.; Savoy-Navarro, A.; Schwickerath, U.; Segar, A.; Sekulin, R.; Siebel, M.; Sisakian, A.; Smadja, G.; Smirnova, O.; Sokolov, A.; Sopczak, A.; Sosnowski, R.; Spassov, T.; Stanitzki, M.; Stocchi, A.; Strauss, J.; Stugu, B.; Szczekowski, M.; Szeptycka, M.; Szumlak, T.; Tabarelli, T.; Taffard, A.C.; Tegenfeldt, F.; Timmermans, Jan; Tkatchev, L.; Tobin, M.; Todorovova, S.; Tome, B.; Tonazzo, A.; Tortosa, P.; Travnicek, P.; Treille, D.; Tristram, G.; Trochimczuk, M.; Troncon, C.; Turluer, M.L.; Tyapkin, I.A.; Tyapkin, P.; Tzamarias, S.; Uvarov, V.; Valenti, G.; Van Dam, Piet; Van Eldik, J.; Van Lysebetten, A.; van Remortel, N.; Van Vulpen, I.; Vegni, G.; Veloso, F.; Venus, W.; Verdier, P.; Verzi, V.; Vilanova, D.; Vitale, L.; Vrba, V.; Wahlen, H.; Washbrook, A.J.; Weiser, C.; Wicke, D.; Wickens, J.; Wilkinson, G.; Winter, M.; Witek, M.; Yushchenko, O.; Zalewska, A.; Zalewski, P.; Zavrtanik, D.; Zhuravlov, V.; Zimine, N.I.; Zintchenko, A.; Zupan, M.
2004-01-01
The DELPHI experiment at the LEP e+e- collider collected almost 700 pb^-1 at centre-of-mass energies above the Z0 mass pole and up to 208 GeV. Those data were used to search for SUSY in the Anomaly Mediated SUSY Breaking (AMSB) scenario with a flavour independent common sfermion mass parameter. The searches covered several possible signatures experimentally accessible at LEP, with either the neutralino, the sneutrino or the stau being the Lightest Supersymmetric Particle (LSP). They included: the search for nearly mass-degenerate chargino and neutralino, which is a typical feature of AMSB; the search for Standard-Model-like or invisibly decaying Higgs boson; the search for stable staus; the search for cascade decays of SUSY particles resulting in the LSP and a low multiplicity final state containing neutrinos. No evidence of a signal was found, and thus constraints were set in the space of the parameters of the model.
Spectral properties in supersymmetric matrix models
Energy Technology Data Exchange (ETDEWEB)
Boulton, Lyonell, E-mail: L.Boulton@hw.ac.uk [Department of Mathematics and Maxwell Institute for Mathematical Sciences, Heriot-Watt University, Edinburgh EH14 4AS (United Kingdom); Garcia del Moral, Maria Pilar, E-mail: garciamormaria@uniovi.es [Departamento de Fisica, Universidad de Oviedo, Avda Calvo Sotelo 18, 33007 Oviedo (Spain); Restuccia, Alvaro, E-mail: arestu@usb.ve [Departamento de Fisica, Universidad Simon Bolivar, Apartado 89000, Caracas (Venezuela, Bolivarian Republic of); Departamento de Fisica, Universidad de Oviedo, Avda Calvo Sotelo 18, 33007 Oviedo (Spain)
2012-03-21
We formulate a general sufficiency criterion for discreteness of the spectrum of both supersymmmetric and non-supersymmetric theories with a fermionic contribution. This criterion allows an analysis of Hamiltonians in complete form rather than just their semiclassical limits. In such a framework we examine spectral properties of various (1+0) matrix models. We consider the BMN model of M-theory compactified on a maximally supersymmetric pp-wave background, different regularizations of the supermembrane with central charges and a non-supersymmetric model comprising a bound state of N D2 with m D0. While the first two examples have a purely discrete spectrum, the latter has a continuous spectrum with a lower end given in terms of the monopole charge.
Kepribadian Dan Komunikasi Susi Pudjiastuti Dalam Membentuk Personal Branding
Directory of Open Access Journals (Sweden)
Stevani
2017-07-01
Full Text Available The life story of Susi Pudjiastuti is admired by many people for her hard work, until becoming successful by having so much company in the field of aviation and fisheries. Susi Pudjiastuti is also well known to the public for his work in the ministry. Good performance makes Susi Pudjiastuti popular among Jokowi's working cabinet. Currently, the Brand Name in humans is personal branding which is the trend of the formation of self-image and the creation of good perception from others to us. This research will discuss about personality, communication and personal branding Susi Pudjiastuti with qualitative research method. Good personality makes Susi Pudjiastuti has the ability to communicate well and liked by the community. Personality and communication can form a personal branding Susi Pudjiastuti a natural. By exposing the personality and communication of Susi Pudjiastuti in forming personal branding, then people will realize the importance of personality and Communication in forming a natural personal branding. Kisah hidup Susi Pudjiastuti banyak dikagumi oleh banyak orang atas kerja kerasnya hingga menjadi sukses dengan memiliki banyak perusahaan di bidang penerbangan dan perikanan. Susi Pudjiastuti juga dikenal baik oleh masyarakat akan kinerjanya dalam bekerja di kementerian. Kinerja yang baik menjadikan Susi Pudjiastuti popular diantara kabinet kerja Jokowi. Saat ini, Sebutan merek pada manusia adalah personal branding yang merupakan trend dari pembentukan pencitraan diri dan penciptaan persepsi yang baik dari orang lain kepada kita. Penelitian ini akan membahas mengenai kepribadian, komunikasi serta personal branding Susi Pudjiastuti dengan metode penelitian kualitatif. Kepribadian yang baik menjadikan Susi Pudjiastuti memiliki kemampuan berkomunikasi dengan baik dan disenangi oleh masyarakat. Kepribadian dan komunikasi tersebut dapat membentuk personal branding Susi Pudjiastuti yang alami. Dengan memaparkan kepribadian dan komunikasi Susi
Susi lubab Concordiale investorit / Sigrid Laev
Laev, Sigrid
2003-01-01
Mart Susi teatas Concordia ülikoolile, et tal on kaks võimalikku investorit, kes on huvitatud kooli tegevuses osalemisest. Üks neist on Läti kõrgem ärikool Turiba, teine võimalik investor on Ameerika päritolu
Concordia soovib Susi lahkumist / Sigrid Laev
Laev, Sigrid
2003-01-01
Concordia eraülikooli töötajad andsid 5. märtsil pärast ametiühingu koosolekut rektor Mart Susile üle ametliku palve tagasi astuda. Plaanid rektori umbusaldamiseks algasid nädala eest, kui selgus M. Susi tegevus kooli ja oma isiklike varade ühendamisel
Project-matrix models of marketing organization
Directory of Open Access Journals (Sweden)
Gutić Dragutin
2009-01-01
Full Text Available Unlike theory and practice of corporation organization, in marketing organization numerous forms and contents at its disposal are not reached until this day. It can be well estimated that marketing organization today in most of our companies and in almost all its parts, noticeably gets behind corporation organization. Marketing managers have always been occupied by basic, narrow marketing activities as: sales growth, market analysis, market growth and market share, marketing research, introduction of new products, modification of products, promotion, distribution etc. They rarely found it necessary to focus a bit more to different aspects of marketing management, for example: marketing planning and marketing control, marketing organization and leading. This paper deals with aspects of project - matrix marketing organization management. Two-dimensional and more-dimensional models are presented. Among two-dimensional, these models are analyzed: Market management/products management model; Products management/management of product lifecycle phases on market model; Customers management/marketing functions management model; Demand management/marketing functions management model; Market positions management/marketing functions management model. .
Electroweak contributions to SUSY particle production processes at the LHC
Energy Technology Data Exchange (ETDEWEB)
Mirabella, Edoardo
2009-07-22
In this thesis we have computed the electroweak contributions of O({alpha}{sub s}{alpha}), O({alpha}{sup 2}) and O({alpha}{sub s}{sup 2}) to three different classes of processes leading to the hadronic production of the SUSY partners of quarks and gluons, i.e. squarks and gluinos. The theoretical framework is the Minimal Supersymmetric extension of the Standard Model, the MSSM. The three processes are gluino pair production, diagonal squark-antisquark and associated squark-gluino production.
Compressed and Split Spectra in Minimal SUSY SO(10
Directory of Open Access Journals (Sweden)
Frank Franz Deppisch
2014-05-01
Full Text Available The non-observation of supersymmetric signatures in searches at the Large Hadron Collider strongly constrains minimal supersymmetric models like the CMSSM. We explore the consequences on the SUSY particle spectrum in a minimal SO(10 with large D-terms and non-universal gaugino masses at the GUT scale. This changes the sparticle spectrum in a testable way and for example can sufficiently split the coloured and non-coloured sectors. The splitting provided by use of the SO(10 D-terms can be exploited to obtain light first generation sleptons or third generation squarks, the latter corresponding to a compressed spectrum scenario.
Searches for RPV SUSY and long-lived particles at the LHC
Liu, Minghui; The ATLAS collaboration
2015-01-01
Both the ATLAS and CMS collaboration have made great effort to search for RPV SUSY and LLP. Tens of models are used to perform studies, and all the observations seem to be in good agreement with background expectation. Most stringent limits up to date are put on these new models.
Elements of matrix modeling and computing with Matlab
White, Robert E
2006-01-01
As discrete models and computing have become more common, there is a need to study matrix computation and numerical linear algebra. Encompassing a diverse mathematical core, Elements of Matrix Modeling and Computing with MATLAB examines a variety of applications and their modeling processes, showing you how to develop matrix models and solve algebraic systems. Emphasizing practical skills, it creates a bridge from problems with two and three variables to more realistic problems that have additional variables. Elements of Matrix Modeling and Computing with MATLAB focuses on seven basic applicat
Overview of SUSY results from the ATLAS experiment
Brazzale, Simone Federico
2014-04-01
The search for Supersymmetric extensions of the Standard Model (SUSY) remains a hot topic in high energy phisycs in the light of the discovery of the Higgs boson with mass of 125 GeV. Supersymmetric particles can cancel out the quadratically-divergent loop corrections to the Higgs boson mass and can explain presence of Dark Matter in the Universe. Moreover, SUSY can unify the gauge couplings of the Standard Model at high energy scales. Under certain theoretical assumptions, some of the super-symmetric particles are preferred to be lighter than one TeV and their discovery can thus be accessible at the LHC. The recent results from searches for Supersymmetry with the ATLAS experiment which utilized up to 21 fb-1 of proton-proton collisions at a center of mass energy of 8 TeV are presented. These searches are focused on inclusive production of squarks and gluinos, on production of third generations squarks, and on electroweak production of charginos and neutralinos. Searches for long-lived particles and R-parity violation are also summarized in the document.
Hangout with CERN: All about SUSY (S03E09)
Kahle, Kate
2013-01-01
On 4th July 2012, CERN announced the discovery of a new boson later confirmed to be "a Higgs boson", but which one? Is it the Higgs boson predicted by the Standard Model of particle physics or one of the five Higgs bosons associated with "supersymmetry", a principle that attempts to fix the few remaining problems of the Standard Model?In this week's hangout we talk about supersymmetry, also known as "SUSY". What is it, why, and how does it link with the Higgs boson? Our host CMS physicist Freya Blekman is joined by SUSY theorist John Ellis, ATLAS physicist Xavier Portell Bueso and CMS physicist Josh Thompson, as well as student intern Jayendra Minakshisundar, with CMS physicist Seth Zenz monitoring social media.Find out more about supersymmetry by watching these videos by Don Lincoln from Fermilab: What is Supersymmetry? http://www.youtube.com/watch?v=0CeLRrBAI60 and Why Supersymmetry? http://www.youtube.com/watch?v=09VbAe9JZ8YRecorded live on 20th June 20...
Overview of SUSY results from the ATLAS experiment
Directory of Open Access Journals (Sweden)
Federico Brazzale Simone
2014-04-01
Full Text Available The search for Supersymmetric extensions of the Standard Model (SUSY remains a hot topic in high energy phisycs in the light of the discovery of the Higgs boson with mass of 125 GeV. Supersymmetric particles can cancel out the quadratically-divergent loop corrections to the Higgs boson mass and can explain presence of Dark Matter in the Universe. Moreover, SUSY can unify the gauge couplings of the Standard Model at high energy scales. Under certain theoretical assumptions, some of the super-symmetric particles are preferred to be lighter than one TeV and their discovery can thus be accessible at the LHC. The recent results from searches for Supersymmetry with the ATLAS experiment which utilized up to 21 fb−1 of proton-proton collisions at a center of mass energy of 8 TeV are presented. These searches are focused on inclusive production of squarks and gluinos, on production of third generations squarks, and on electroweak production of charginos and neutralinos. Searches for long-lived particles and R-parity violation are also summarized in the document.
An algebraic study of the matrix meta-population model
Sylviani, Sisilia; Carnia, Ema; Supriatna, A. K.
2017-10-01
In studying the population living in some patches, a single patch model usually generalizes into a meta-population model. Roughly speaking a meta-population is population consisting of some sub-populations, such as sub-population reflecting different life stages of the population or different habitat of patches. In a meta-population framework the dynamics of population within and between patches can be easily studied. This paper will discuss the matrix meta-population model that describes the growth and reproduction within the patches denoted by F. The matrix F is obtained by multiplying three matrices; the transpose of a permutation matrix, a block diagonal matrix in which its diagonal blocks is a matrix A j , and the permutation matrix. The matrix A j is the real non-negative matrix that represents the dynamics of population growth in the patch j. The permutation matrix has a special form that has properties that are more specific than the general permutation matrix. This paper will also gives a brief application for the matrix F. This will provide a space for exploring the characterization of the matrix F from algebraic point of view.
Matrix diffusion model. In situ tests using natural analogues
Energy Technology Data Exchange (ETDEWEB)
Rasilainen, K. [VTT Energy, Espoo (Finland)
1997-11-01
Matrix diffusion is an important retarding and dispersing mechanism for substances carried by groundwater in fractured bedrock. Natural analogues provide, unlike laboratory or field experiments, a possibility to test the model of matrix diffusion in situ over long periods of time. This thesis documents quantitative model tests against in situ observations, done to support modelling of matrix diffusion in performance assessments of nuclear waste repositories. 98 refs. The thesis includes also eight previous publications by author.
Efficient Matrix Models for Relational Learning
2009-10-01
New York, 1994. [63] Daniel D. Lee and H. Sebastian Seung . Algorithms for non-negative matrix factor- ization. In Todd K. Leen, Thomas G. Dietterich...135] Shenghuo Zhu, Kai Yu, Yun Chi, and Yihong Gong. Combining content and link for classification using matrix factorization. In Wessel Kraaij
Matrix approach to modelling of SAR signals
Lidicky, L.; Hoogeboom, P.
2005-01-01
The paper presents a matrix approach to implementation of SAR signal generating and processing schemes. This approach is advantageous when matrix oriented software such as Matlab is used. Algorithms written in this type of software packages run faster compared to the same algorithms written for the
Highlights from SUSY searches with ATLAS
Mitsou, V A
2014-01-01
Supersymmetry (SUSY) is one of the most relevant scenarios of new physics searched by the ATLAS experiment at the CERN Large Hadron Collider. In this write-up the principal search strategies employed by ATLAS are outlined and the most recent results for analyses targeting SUSY discovery are discussed. A wide range of signatures is covered motivated by various theoretical scenarios and topologies: strong production, third-generation fermions, long-lived particles and R-parity violation, among others. The results are based on up to ~5/fb of data recorded during 2010 - 2011 at sqrt(s) = 7 TeV centre-of-mass energy by the ATLAS experiment at the LHC.
Population matrix models and palm resource management
Directory of Open Access Journals (Sweden)
1992-01-01
Full Text Available MATRICES DE POPULATIONS ET MISE EN VALEUR DES PALMIERS. Au cours des 20 dernières années, les structures de population de nombreuses espèces de palmiers ont été décrites et discutées. La croissance et la stabilité des populations ont été analysées à laide de matrices. Dans cet article, nous reprenons un modèle et en discutons les aspects méthodologiques en vue dune estimation des paramètres de lhistoire de la vie des palmiers. Les généralisations résultant de précédentes études sont présentées et les conséquences pour la mise en valeur des palmiers, concernant en particulier la confection de toitures, les fruits, la récolte des stipes, sont discutées. MATRICES DE POBLACIONES Y MANEJO DE PALMERAS. En los últimos 20 años, las estructuras de población de numerosas especies de palmeras han sido descritas y discutidas. El crecimiento y la estabilidad de las poblaciones han sido analizadas, utilizando matrices. En el presente artículo, presentamos un modelo y discutimos los aspectos metodológicos específicos para hacer una estimación de los parámetros de la historia de la vida de las palmeras. Son presentadas las generalizaciones diseñadas por estudios previos, y discutidas las implicancias en el manejo de las palmeras, en cuanto a techado, frutas, cosecha de los estípites. Population structures of numerous palm species have been described and discussed in the last 20 years. Population growth and stability have been analyzed with matrix models. In this paper we review matrix models and discuss methodological issues specific to estimating palm life history parameters. Generalizations drawn from previous studies are presented and implications for palm resource management, specifically for thatch, fruit, and stem harvest, are discussed.
Harmonic Oscillator SUSY Partners and Evolution Loops
Directory of Open Access Journals (Sweden)
David J. Fernández
2012-07-01
Full Text Available Supersymmetric quantum mechanics is a powerful tool for generating exactly solvable potentials departing from a given initial one. If applied to the harmonic oscillator, a family of Hamiltonians ruled by polynomial Heisenberg algebras is obtained. In this paper it will be shown that the SUSY partner Hamiltonians of the harmonic oscillator can produce evolution loops. The corresponding geometric phases will be as well studied.
Energy Technology Data Exchange (ETDEWEB)
Brun, Pierre [Laboratoire d' Annecy-le-vieux de Physique des Particules, CNRS/IN2P3/Univ. de Savoie, 9 Chemin de Bellevue - BP 110 F-74941 Annecy-le-Vieux CEDEX (France)
2006-03-15
In the quest for indirect signals from dark matter annihilation, powerful computation codes are required. I report here a new code based on micrOMEGAs devoted to the analysis of such signals in term of Supersymmetry. It computes gamma rays and positrons fluxes in a general SuSy model, as well as the other charged cosmic rays and neutrinos source terms. This work aims to propose an alternative to the DarkSUSY code by providing inclusive signals from SuSy for dark matter indirect searches. Therefore it can be used for sensitivity studies and data analysis. (author)
A diode matrix is an extremely low-density form of read-only memory. It's one of the earliest forms of ROMs (dating back to the 1950s). Each bit in the ROM is represented by the presence or absence of one diode. The ROM is easily user-writable using a soldering iron and pair of wire cutters.This diode matrix board is a floppy disk boot ROM for a PDP-11, and consists of 32 16-bit words. When you access an address on the ROM, the circuit returns the represented data from that address.
SUSY formalism for the symmetric double well potential
Indian Academy of Sciences (India)
SUSY; moving boundary condition; exactly solvable; symmetric double well; NH3 molecule. PACS Nos 02.30.Ik; 03.50. ... Various work has been done to construct the integrable potentials by SUSY Darboüx for- malism. If the boundary .... ϵj being the energy eigenvalue for the jth level. So the obtained potential [1,4,5] is.
Results from GRACE/SUSY at one-loop
Indian Academy of Sciences (India)
We report the recent development on the SUSY calculations with the help of GRACE system. GRACE/SUSY/1LOOP is the computer code which can generate Feynman diagrams in the MSSM automatically and compute one-loop amplitudes in the numerical way. We present new results of various two-body decay widths ...
Maksuamet võtmas Susi vara / Sigrid Laev
Laev, Sigrid
2003-01-01
Maksuamet võib alustada pankrotiohus Concordia ülikooli ja selle rektori Mart Susi vara realiseerimist, sest kooli omanik Concordia Varahaldus OÜ pole maksuametile lubatud ajal raha üle kandnud. Väidetavalt maksis Susi õppejõududele palka offshore-firma kaudu. AS Audentes on valmis Concordiat ostma
Mari-Ann Susi õigustas ülikooli raha kasutamist
2003-01-01
M.-A. Susi eitas ülikooli palgaraha kasutamist isikliku mõisa ülalpidamiseks ning tahtlikult riigimaksudest kõrvalehoidmist, nende üks ideid oli Susi sõnul arendada mõis konverentsiturismi keskuseks, mis oleks majanduslikult kasu toonud ka ülikoolile
Baer, Howard; Barger, Vernon; Savoy, Mike
2015-06-01
More than 30 years ago, Arnowitt-Chamseddine-Nath and others established the compelling framework of supergravity gauge theories (SUGRA) as a picture for the next step in beyond the standard model physics. We review the current SUGRA scenario in light of recent data from LHC8 collider searches and the Higgs boson discovery. While many SUSY and non-SUSY scenarios are highly disfavored or even excluded by LHC, the essential SUGRA scenario remains intact and as compelling as ever. For naturalness, some non-universality between matter and Higgs sector soft terms is required along with substantial trilinear soft terms. SUSY models with radiatively-driven naturalness are found with high scale fine-tuning at a modest ˜ 10%. In this case, natural SUSY might be discovered at LHC13 but could also easily elude sparticle search endeavors. A linear {{e}+}{{e}-} collider with \\sqrt{s}\\gt 2m(higgsino) is needed to provide the definitive search for the required light higgsino states which are the hallmark of natural SUSY. In the most conservative scenario, we advocate inclusion of a Peccei-Quinn sector so that dark matter is composed of a WIMP/axion admixture i.e. two dark matter particles.
Solution of Second-Order IVP and BVP of Matrix Differential Models Using Matrix DTM
Directory of Open Access Journals (Sweden)
Reza Abazari
2012-01-01
Full Text Available We introduce a matrix form of differential transformation method (DTM and apply for nonlinear second-order initial value problems (IVPs and boundary value problems (BVPs of matrix models which are given by (=(,(,( and subject to initial conditions (=0,(=1 and boundary conditions (=0,(=1, where 0,1∈×. Also the convergence of present method is established. Several illustrative examples are given to demonstrate the effectiveness of the present method.
The topological matrix model of c=1 string
Imbimbo, Camillo; Imbimbo, Camillo; Mukhi, Sunil
1995-01-01
We derive a Kontsevich-type matrix model for the c=1 string directly from the W-infinity solution of the theory. The model that we obtain is different from previous proposals, which are proven to be incorrect. Our matrix model contains the Penner and Kontsevich cases, and we study its quantum effective action. The simplicity of our model leads to an encouraging interpretation in the context of background-independent noncritical string field theory.
Energy Technology Data Exchange (ETDEWEB)
Zivkovic, L.
2011-07-01
In this article results from supersymmetry searches at D0 and CDF are reported. Searches for third generation squarks, searches for gauginos, and searches for models with R-parity violation are described. As no signs of supersymmetry for these models are observed, the most stringent limits to date are presented.
Comparison Of Models Of Metal-Matrix Composites
Bigelow, C. A.; Johnson, W. S.; Naik, R. A.
1994-01-01
Report presents comparative review of four mathematical models of micromechanical behaviors of fiber/metal-matrix composite materials. Models differ in various details, all based on properties of fiber and matrix constituent materials, all involve square arrays of fibers continuous and parallel and all assume complete bonding between constituents. Computer programs implementing models used to predict properties and stress-vs.-strain behaviors of unidirectional- and cross-ply laminated composites made of boron fibers in aluminum matrices and silicon carbide fibers in titanium matrices. Stresses in fiber and matrix constituent materials also predicted.
Costs equations for cost modeling: application of ABC Matrix
Directory of Open Access Journals (Sweden)
Alex Fabiano Bertollo Santana
2016-03-01
Full Text Available This article aimed at providing an application of the ABC Matrix model - a management tool that models processes and activities. The ABC Matrix is based on matrix multiplication, using a fast algorithm for the development of costing systems and the subsequent translation of the costs in cost equations and systems. The research methodology is classified as a case study, using the simulation data to validate the model. The conclusion of the research is that the algorithm presented is an important development, because it is an effective approach to calculating the product cost and because it provides simple and flexible algorithm design software for controlling the cost of products
Neutrino Masses in SUSY theories
Lola, S
1999-01-01
We discuss aspects of neutrino masses and lepton-number violation, in the light of the observations of Super-Kamiokande. As a first step, we use the data from various experiments, in order to obtain a phenomenological understanding of neutrino mass textures. We then investigate how the required patterns of neutrino masses and mixings are related to the flavour structure of the underlying theory. In supersymmetric extensions of the Standard Model, renormalisation group effects can have important implications: for small tanb, bottom-tau unification indicates the presence of significant muon-tau flavour mixing. The evolution of the neutrino mixing may be described by simple semi-analytic expressions, which confirm that, for large tanb, very small mixing at the GUT scale may be amplified to maximal mixing at low energies, and vice versa. Passing to specific models, we first discuss the predictions for neutrino masses in different GUT models (including superstring-embedded solutions). Imposing the requirement for ...
Zwirner, F
1992-01-01
We summarize the present status of low-energy supersymmetry, exemplified by the Minimal Supersymmetric extension of the Standard Model (MSSM). We review the searches for Supersymmetric particles and supersymmetric Higgs bosons. We conclude with some comments on the open theoretical problems related to spontaneous supersymmetry breaking in the underlying fundamental theory.
Modeling the formation of cell-matrix adhesions on a single 3D matrix fiber.
Escribano, J; Sánchez, M T; García-Aznar, J M
2015-11-07
Cell-matrix adhesions are crucial in different biological processes like tissue morphogenesis, cell motility, and extracellular matrix remodeling. These interactions that link cell cytoskeleton and matrix fibers are built through protein clutches, generally known as adhesion complexes. The adhesion formation process has been deeply studied in two-dimensional (2D) cases; however, the knowledge is limited for three-dimensional (3D) cases. In this work, we simulate different local extracellular matrix properties in order to unravel the fundamental mechanisms that regulate the formation of cell-matrix adhesions in 3D. We aim to study the mechanical interaction of these biological structures through a three dimensional discrete approach, reproducing the transmission pattern force between the cytoskeleton and a single extracellular matrix fiber. This numerical model provides a discrete analysis of the proteins involved including spatial distribution, interaction between them, and study of the different phenomena, such as protein clutches unbinding or protein unfolding. Copyright © 2015 Elsevier Ltd. All rights reserved.
Impact of SUSY-QCD corrections to neutralino-squark coannihilation on the dark matter relic density
Energy Technology Data Exchange (ETDEWEB)
Harz, Julia [Deutsches Elektronen-Synchrotron, Hamburg (Germany); Herrmann, Bjoern [Laboratoire d' Annecy de Physique Theorique, Annecy-le-Vieux (France); Klasen, Michael [Institute for Theoretical Physics, University of Muenster (Germany); Kovarik, Karol [Karlsruhe Institute of Technology, Karlsruhe (Germany); Le Boulc' h, Quentin [Laboratoire de Physique Subatomique et de Cosmologie, Grenoble (France)
2012-07-01
A powerful method to constrain the parameter space of theories beyond the Standard Model is to compare the predicted dark matter relic density with data from cosmological precision measurements, in particular from the WMAP satellite. On the particle physics side, the main uncertainty on the relic density arises from the (co-)annihilation cross sections of the dark matter particle. After a motivation for including higher order corrections in the prediction of the relic density, the project DM rate at NLO is presented. This software package allows one to compute the neutralino (co-)annihilation cross sections including SUSY-QCD corrections at the one-loop level and to evaluate their effect on the relic density using a link to the public codes MicrOMEGAs and DarkSUSY. Recent results of the impact of SUSY-QCD corrections on the neutralino pair annihilation cross section are discussed, and first results on neutralino-squark coannihilation are shown.
An Index for Intersecting Branes in Matrix Models
Directory of Open Access Journals (Sweden)
Harold Steinacker
2013-11-01
Full Text Available We introduce an index indicating the occurrence of chiral fermions at the intersection of branes in matrix models. This allows to discuss the stability of chiral fermions under perturbations of the branes.
Renormalization group approach to matrix models via noncommutative space
Energy Technology Data Exchange (ETDEWEB)
Kuroki, T. [Kobayashi-Maskawa Institute for the Origin of Particles and the Universe (KMI), Nagoya University, Furo-cho, Chikusa-ku, Nagoya Aichi 464-8602 (Japan); Kawamoto, S. [National Center for Theoretical Sciences, Hsinchu 30013 (China); Tomino, D. [Department of Physics, Tunghai University, Taichung 40704 (China)
2014-09-11
We develop a new method for analyzing the large-N limit of matrix models. We assign the concept of energy to each matrix element and integrate the most highest energy to get a new matrix model which has reduced rank. By regarding this procedure as a renormalization group, we deduce the critical exponents in the large-N limit by elaborating fixed points of renormalization group transformation. For consistency of our method, we compare our result to that obtained by another method and find nice agreement. (Copyright copyright 2014 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)
Joint Learning of Multiple Sparse Matrix Gaussian Graphical Models.
Huang, Feihu; Chen, Songcan
2015-11-01
We consider joint learning of multiple sparse matrix Gaussian graphical models and propose the joint matrix graphical Lasso to discover the conditional independence structures among rows (columns) in the matrix variable under distinct conditions. The proposed approach borrows strength across the different graphical models and is based on the maximum likelihood with penalized row and column precision matrices, respectively. In particular, our model is more parsimonious and flexible than the joint vector graphical models. Furthermore, we establish the asymptotic properties of our model on consistency and sparsistency. And the asymptotic analysis shows that our model enjoys a better convergence rate than the joint vector graphical models. Extensive simulation experiments demonstrate that our methods outperform state-of-the-art methods in identifying graphical structures and estimating precision matrices. Moreover, the effectiveness of our methods is also illustrated via a real data set analysis. Sparsistency is shorthand for consistency of the sparsity pattern of the parameters.
An R-Parity Breaking SUSY Solution to the $R_b$ and ALEPH Anomalies
Choudhury, D; Choudhury, Debajyoti
1996-01-01
We discuss an optimal $R$-parity breaking SUSY solution to the $R_b$ excess as well as the ALEPH 4-jet anomaly. The latter arises from the pair production of stop via chargino decay at LEP1.5, followed by its $R$--violating decay into a light quark pair. The model satisfies top quark and $Z$--boson decay constraints along with gaugino mass unification.
Matrix models of RNA folding with external interactions: A review
Indian Academy of Sciences (India)
The matrix model of (simpliﬁed) RNA folding with an external linear interaction in the action of the partition function is reviewed. The important results for structure combinatorics of the model are discussed and analysed in terms of the already existing models.
Diagnosing declining grassland wader populations using simple matrix models
Klok, C.; Roodbergen, M.; Hemerik, L.
2009-01-01
Many populations of wader species have shown a strong decline in number in Western-Europe in recent years. The use of simple population models such as matrix models can contribute to conserve these populations by identifying the most profitable management measures. Parameterization of such models is
Matrix coordinate Bethe Ansatz: applications to XXZ and ASEP models
Energy Technology Data Exchange (ETDEWEB)
Crampe, N [Laboratoire Charles Coulomb, UMR 5221, Universite Montpellier 2, F-34095 Montpellier (France); Ragoucy, E [Laboratoire de Physique Theorique LAPTH, CNRS and Universite de Savoie, 9 chemin de Bellevue, BP 110, F-74941 Annecy-le-Vieux Cedex (France); Simon, D, E-mail: nicolas.crampe@univ-montp2.fr, E-mail: ragoucy@lapp.in2p3.fr, E-mail: damien.simon@upmc.fr [LPMA, Universite Pierre et Marie Curie, Case Courrier 188, 4 place Jussieu, 75252 Paris Cedex 05 (France)
2011-10-07
We present the construction of the full set of eigenvectors of the open asymmetric simple exclusion process (ASEP) and XXZ models with special constraints on the boundaries. The method combines both recent constructions of coordinate Bethe Ansatz and the old method of matrix Ansatz specific to the ASEP. This 'matrix coordinate Bethe Ansatz' can be viewed as a non-commutative coordinate Bethe Ansatz, the non-commutative part being related to the algebra appearing in the matrix Ansatz. (paper)
Proposed framework for thermomechanical life modeling of metal matrix composites
Energy Technology Data Exchange (ETDEWEB)
Halford, G.R.; Lerch, B.A.; Saltsman, J.F.
1993-07-01
The framework of a mechanics of materials model is proposed for thermomechanical fatigue (TMF) life prediction of unidirectional, continuous-fiber metal matrix composites (MMC's). Axially loaded MMC test samples are analyzed as structural components whose fatigue lives are governed by local stress-strain conditions resulting from combined interactions of the matrix, interfacial layer, and fiber constituents. The metallic matrix is identified as the vehicle for tracking fatigue crack initiation and propagation. The proposed framework has three major elements. First, TMF flow and failure characteristics of in situ matrix material are approximated from tests of unreinforced matrix material, and matrix TMF life prediction equations are numerically calibrated. The macrocrack initiation fatigue life of the matrix material is divided into microcrack initiation and microcrack propagation phases. Second, the influencing factors created by the presence of fibers and interfaces are analyzed, characterized, and documented in equation form. Some of the influences act on the microcrack initiation portion of the matrix fatigue life, others on the microcrack propagation life, while some affect both. Influencing factors include coefficient of thermal expansion mismatch strains, residual (mean) stresses, multiaxial stress states, off-axis fibers, internal stress concentrations, multiple initiation sites, nonuniform fiber spacing, fiber debonding, interfacial layers and cracking, fractured fibers, fiber deflections of crack fronts, fiber bridging of matrix cracks, and internal oxidation along internal interfaces. Equations exist for some, but not all, of the currently identified influencing factors. The third element is the inclusion of overriding influences such as maximum tensile strain limits of brittle fibers that could cause local fractures and ensuing catastrophic failure of surrounding matrix material.
Milline on Eesti õiguslik mõte? / Mart Susi
Susi, Mart, 1965-
1996-01-01
Concordia Ülikooli rektori, vandeadvokaat Mart Susi arvamus Eesti õigusliku mõtte olemusest ja arengusuundadest, sealhulgas ka Eesti Akadeemilise Õigusteaduse Seltsi ja Eesti Juristide Liidu ühisest aastakoosolekust
Lauri, miks Sul lapsi ei ole? / Endel Susi
Susi, Endel-Haljand, 1940-
2006-01-01
Rahvaliidu Lääne Ühenduse juhatuse esimehe Endel Susi vastukaja Lauri Luige artiklile "Saagu meid palju ja elagem kaua!" 6. juuni "Lääne Elus", kus ta otsib alternatiive negatiivse iibe pidurdamiseks
Concordia elas tuleviku arvelt / Mart Susi ; interv. Krister Kivi
Susi, Mart, 1965-
2003-01-01
Ilmunud ka: Infopress 21. märts nr. 12 lk. 30-31. Concordia Ülikooli rektor Mart Susi räägib kooli senisest juhtimisest ning asjaoludest, mis on põhjustanud pankroti. Tabel: Concordia kronoloogia
A Dynamic Model for Direct and Indirect Matrix Converters
Directory of Open Access Journals (Sweden)
Mohamad Hosseini Abardeh
2014-01-01
Full Text Available The complicated modulation algorithm and the high switching frequency are two main hindrances in the analysis and simulation of matrix converters (MCs based systems. To simplify the analysis and accelerate the simulation of MCs, a unique dynamic model is presented for the MC, which is independent of MC type (direct or indirect and the modulation algorithm. All the input and output variables are transferred to the respective reference frames and their relations and limits are calculated. Based on the proposed equations, an equivalent circuit model is presented which can predict all the direct and indirect matrix converters dynamic and steady state behaviors without the need for small simulation time steps. Validity of the proposed model is evaluated using simulation of the precise model. Moreover, experimental results from a laboratory matrix converter setup are provided to verify the accuracy of the simulation results.
Decoupling of gravity on non-susy Dp branes
Energy Technology Data Exchange (ETDEWEB)
Nayek, Kuntal; Roy, Shibaji [Saha Institute of Nuclear Physics,1/AF Bidhannagar, Calcutta, 700064 (India)
2016-03-15
We study the graviton scattering in the background of non-susy Dp branes of type II string theories consisting of a metric, a dilaton and a (p+1) form gauge field. We show numerically that in these backgrounds graviton experiences a scattering potential which takes the form of an infinite barrier in the low energy (near brane) limit for p≤5 and therefore is never able to reach the branes. This shows, contrary to what is known in the literature, that gravity indeed decouples from the non-susy Dp branes for p≤5. For non-susy D6 brane, gravity couples as there is no such barrier for the potential. To give further credence to our claim we solve the scattering equation in some situation analytically and calculate the graviton absorption cross-sections on the non-susy branes and show that they vanish for p≤4 in the low energy limit. This shows, as in the case of BPS branes, that gravity does decouple for non-susy Dp branes for p≤4 but it does not decouple for D6 brane as the potential here is always attractive. We argue for the non-susy D5 brane that depending on one of the parameters of the solution gravity either always decouples (unlike the BPS D5 brane) or it decouples when the energy of the graviton is below certain critical value, otherwise it couples, very similar to BPS D5 brane.
Modeling food matrix effects on chemical reactivity: Challenges and perspectives.
Capuano, Edoardo; Oliviero, Teresa; van Boekel, Martinus A J S
2017-06-29
The same chemical reaction may be different in terms of its position of the equilibrium (i.e., thermodynamics) and its kinetics when studied in different foods. The diversity in the chemical composition of food and in its structural organization at macro-, meso-, and microscopic levels, that is, the food matrix, is responsible for this difference. In this viewpoint paper, the multiple, and interconnected ways the food matrix can affect chemical reactivity are summarized. Moreover, mechanistic and empirical approaches to explain and predict the effect of food matrix on chemical reactivity are described. Mechanistic models aim to quantify the effect of food matrix based on a detailed understanding of the chemical and physical phenomena occurring in food. Their applicability is limited at the moment to very simple food systems. Empirical modeling based on machine learning combined with data-mining techniques may represent an alternative, useful option to predict the effect of the food matrix on chemical reactivity and to identify chemical and physical properties to be further tested. In such a way the mechanistic understanding of the effect of the food matrix on chemical reactions can be improved.
A Matrix Model of the Small Group: Part 2.
Boyd, Robert D.
1984-01-01
Presents the second part of a report on the matrix model for the study of small groups considering implications of the model and its translation into operational terms. Addresses primary group tasks such as identity formation, modes of relating, and reality adaptation. (LLL)
Hyperstate matrix models : extending demographic state spaces to higher dimensions
Roth, G.; Caswell, H.
2016-01-01
1. Demographic models describe population dynamics in terms of the movement of individuals among states (e.g. size, age, developmental stage, parity, frailty, physiological condition). Matrix population models originally classified individuals by a single characteristic. This was enlarged to two
A hierarchical model for ordinal matrix factorization
DEFF Research Database (Denmark)
Paquet, Ulrich; Thomson, Blaise; Winther, Ole
2012-01-01
their ratings for other movies. The Netflix data set is used for evaluation, which consists of around 100 million ratings. Using root mean-squared error (RMSE) as an evaluation metric, results show that the suggested model outperforms alternative factorization techniques. Results also show how Gibbs sampling...
Stress corrosion cracking of metal matrix composites: Modeling and experiment
Energy Technology Data Exchange (ETDEWEB)
Jones, R.H.
1990-10-01
The stress corrosion crack growth ate of metal matrix composites has been described by a model which is dependent on the length-to- diameter ({ell}/d) ratio and volume fraction of the reinforcing phase and matrix creep component. The model predicts a large dependence of the stress corrosion crack growth rate of a metal matrix composite on {ell}/d and matrix creep component and a small dependence on the volume fraction of reinforcement. Experimentally determined crack growth rates for 7090 Al/SiC tested in 3.5% NcCl solution, 6061 Al/SiC tested in moist air with NaCl and immersed in NaCl solution, and Mg/Al{sub 2}0{sub 3} tested in a chloride/chromate solution are all consistent with the model. The close correspondence between the model and experiment for a matrix creep stress exponent of 3 suggest that there is little corrosion damage to the reinforcing phase in these systems. 16 refs., 5 figs.
Dynamics Analysis for Hydroturbine Regulating System Based on Matrix Model
Directory of Open Access Journals (Sweden)
Jiafu Wei
2017-01-01
Full Text Available The hydraulic turbine model is the key factor which affects the analysis precision of the hydraulic turbine governing system. This paper discusses the basic principle of the hydraulic turbine matrix model and gives two methods to realize. Using the characteristic matrix to describe unit flow and torque and their relationship with the opening and unit speed, it can accurately represent the nonlinear characteristics of the turbine, effectively improve the convergence of simulation process, and meet the needs of high precision real-time simulation of power system. Through the simulation of a number of power stations, it indicates that, by analyzing the dynamic process of the hydraulic turbine regulating with 5-order matrix model, the calculation results and field test data will have good consistency, and it can better meet the needs of power system dynamic simulation.
Super Yang-Mills theory as a random matrix model
Energy Technology Data Exchange (ETDEWEB)
Siegel, W. [Institute for Theoretical Physics, State University of New York, Stony Brook, New York 11794-3840 (United States)
1995-07-15
We generalize the Gervais-Neveu gauge to four-dimensional {ital N}=1 superspace. The model describes an {ital N}=2 super Yang-Mills theory. All chiral superfields ({ital N}=2 matter and ghost multiplets) exactly cancel to all loops. The remaining Hermitian scalar superfield (matrix) has a renormalizable massive propagator and simplified vertices. These properties are associated with {ital N}=1 supergraphs describing a superstring theory on a random lattice world sheet. We also consider all possible finite matrix models, and find they have a universal large-color limit. These could describe gravitational strings if the matrix-model coupling is fixed to unity, for exact electric-magnetic self-duality.
Solutions of matrix models in the DIII generator ensemble
Roussel, Harold
1994-01-01
In this paper we solve two matrix models, using standard and new techniques. The two models are represented by special form of antisymmetric matrices and are classified in the DIII generator ensemble. It is shown that, in the double scaling limit, their free energy has the same behavior as previous models describing oriented and unoriented surfaces. We also found an additional solution for the first model.
Leptogenesis in a Δ(27)×SO(10) SUSY GUT
Energy Technology Data Exchange (ETDEWEB)
Björkeroth, Fredrik [School of Physics and Astronomy, University of Southampton,SO17 1BJ Southampton (United Kingdom); Anda, Francisco J. de [Departamento de Física, CUCEI, Universidad de Guadalajara,Guadalajara (Mexico); Varzielas, Ivo de Medeiros; King, Stephen F. [School of Physics and Astronomy, University of Southampton,SO17 1BJ Southampton (United Kingdom)
2017-01-17
Although SO(10) Supersymmetric (SUSY) Grand Unification Theories (GUTs) are very attractive for neutrino mass and mixing, it is often quite difficult to achieve successful leptogenesis from the lightest right-handed neutrino N{sub 1} due to the strong relations between neutrino and up-type quark Yukawa couplings. We show that in a realistic model these constraints are relaxed, making N{sub 1} leptogenesis viable. To illustrate this, we calculate the baryon asymmetry of the Universe Y{sub B} from flavoured N{sub 1} leptogenesis in a recently proposed Δ(27)×SO(10) SUSY GUT. The flavoured Boltzmann equations are solved numerically, and comparison with the observed Y{sub B} places constraints on the allowed values of right-handed neutrino masses and neutrino Yukawa couplings. The flavoured SO(10) SUSY GUT is not only fairly complete and predictive in the lepton sector, but can also explain the BAU through leptogenesis with natural values in the lepton sector albeit with some tuning in the quark sector.
Hurwitz numbers, matrix models and enumerative geometry
Bouchard, Vincent
2007-01-01
We propose a new, conjectural recursion solution for Hurwitz numbers at all genera. This conjecture is based on recent progress in solving type B topological string theory on the mirrors of toric Calabi-Yau manifolds, which we briefly review to provide some background for our conjecture. We show in particular how this B-model solution, combined with mirror symmetry for the one-leg, framed topological vertex, leads to a recursion relation for Hodge integrals with three Hodge class insertions. Our conjecture in Hurwitz theory follows from this recursion for the framed vertex in the limit of infinite framing.
Explicit examples of DIM constraints for network matrix models
Energy Technology Data Exchange (ETDEWEB)
Awata, Hidetoshi [Graduate School of Mathematics, Nagoya University,Nagoya, 464-8602 (Japan); Kanno, Hiroaki [Graduate School of Mathematics, Nagoya University,Nagoya, 464-8602 (Japan); KMI, Nagoya University,Nagoya, 464-8602 (Japan); Matsumoto, Takuya [Graduate School of Mathematics, Nagoya University,Nagoya, 464-8602 (Japan); Mironov, Andrei [Theory Department, Lebedev Physics Institute,Leninsky pr., 53, Moscow 119991 (Russian Federation); ITEP,Bol.Cheremushkinskaya, 25, Moscow 117218 (Russian Federation); Institute for Information Transmission Problems,Bol.Karetny, 19 (1), Moscow 127994 (Russian Federation); National Research Nuclear University MEPhI,Kashirskoe sh., 31, Moscow 115409 (Russian Federation); Morozov, Alexei [ITEP,Bol.Cheremushkinskaya, 25, Moscow 117218 (Russian Federation); Institute for Information Transmission Problems,Bol.Karetny, 19 (1), Moscow 127994 (Russian Federation); National Research Nuclear University MEPhI,Kashirskoe sh., 31, Moscow 115409 (Russian Federation); Morozov, Andrey [Institute for Information Transmission Problems,Bol.Karetny, 19 (1), Moscow 127994 (Russian Federation); National Research Nuclear University MEPhI,Kashirskoe sh., 31, Moscow 115409 (Russian Federation); Laboratory of Quantum Topology, Chelyabinsk State University,Bratiev Kashirinyh, 129, Chelyabinsk 454001 (Russian Federation); Ohkubo, Yusuke [Graduate School of Mathematics, Nagoya University,Nagoya, 464-8602 (Japan); Zenkevich, Yegor [ITEP,Bol.Cheremushkinskaya, 25, Moscow 117218 (Russian Federation); Institute for Nuclear Research,60-letiya Oktyabrya pr., 7a, Moscow 117312 (Russian Federation); National Research Nuclear University MEPhI,Kashirskoe sh., 31, Moscow 115409 (Russian Federation)
2016-07-20
Dotsenko-Fateev and Chern-Simons matrix models, which describe Nekrasov functions for SYM theories in different dimensions, are all incorporated into network matrix models with the hidden Ding-Iohara-Miki (DIM) symmetry. This lifting is especially simple for what we call balanced networks. Then, the Ward identities (known under the names of Virasoro/W-constraints or loop equations or regularity condition for qq-characters) are also promoted to the DIM level, where they all become corollaries of a single identity.
On the complete perturbative solution of one-matrix models
Directory of Open Access Journals (Sweden)
A. Mironov
2017-08-01
Full Text Available We summarize the recent results about complete solvability of Hermitian and rectangular complex matrix models. Partition functions have very simple character expansions with coefficients made from dimensions of representation of the linear group GL(N, and arbitrary correlators in the Gaussian phase are given by finite sums over Young diagrams of a given size, which involve also the well known characters of symmetric group. The previously known integrability and Virasoro constraints are simple corollaries, but no vice versa: complete solvability is a peculiar property of the matrix model (hypergeometric τ-functions, which is actually a combination of these two complementary requirements.
Score Matrix for HWBI Forecast Model
2000-2010 Annual State-Scale Service and Domain scores used to support the approach for forecasting EPA's Human Well-Being Index. A modeling approach was developed based relationship function equations derived from select economic, social and ecosystem final goods and service scores and calculated human well-being index and related domain scores. These data are being used in a secondary capacity. The foundational data and scoring techniques were originally described in: a) U.S. EPA. 2012. Indicators and Methods for Constructing a U.S. Human Well-being Index (HWBI) for Ecosystem Services Research. Report. EPA/600/R-12/023. pp. 121; and b) U.S. EPA. 2014. Indicators and Methods for Evaluating Economic, Ecosystem and Social Services Provisioning. Report. EPA/600/R-14/184. pp. 174. Mode Smith, L. M., Harwell, L. C., Summers, J. K., Smith, H. M., Wade, C. M., Straub, K. R. and J.L. Case (2014).This dataset is associated with the following publication:Summers , K., L. Harwell , and L. Smith. A Model For Change: An Approach for Forecasting Well-Being From Service-Based Decisions. ECOLOGICAL INDICATORS. Elsevier Science Ltd, New York, NY, USA, 69: 295-309, (2016).
Transmission line matrix modelling of thermal injuries to skin.
Aliouat Bellia, S; Saidane, A; Hamou, A; Benzohra, M; Saiter, J M
2008-08-01
A numerical model based on the transmission line matrix method is presented for the quantitative prediction of skin burn resulting from exposure of a specific region of human skin surface to a high temperature heat source. Transient temperatures were numerically estimated by Pennes' bioheat equation, and the damage function denoting the extent of burn was calculated using the Arrhenius assumptions for protein damage rate. A two-dimensional transmission line matrix model was used to predict the effects of exposure time and structure thicknesses on the transient temperature distribution and damage extent. Compared with other numerical sources the transmission line matrix results revealed good agreement, suggesting that this method may be an effective tool for the thermal diagnostic of burns.
Matrix models with Penner interaction inspired by interacting ...
Indian Academy of Sciences (India)
tems [5], wireless communication [6], stock and financial market [7] and many more. In many of these applications, universal properties of the eigenvalue statistics of the random matrix models are used like the spacing distributions. More recently, it has been applied to study RNA structure combinatorics which includes the ...
Matrix models for 5d super Yang-Mills
Minahan, Joseph A.
2017-11-01
In this contribution to the issue on localization in gauge theories we investigate the matrix models derived from localizing N=1 super Yang-Mills on S 5. We consider the large-N limit and attempt to solve the matrix model by a saddle-point approximation. In general it is not possible to find an analytic solution, but at the weak and the strong limits of the ’t Hooft coupling there are dramatic simplifications that allows us to extract most of the interesting information. At weak coupling we show that the matrix model is close to the Gaussian matrix model and that the free-energy scales as N 2. At strong coupling we show that if the theory contains one adjoint hypermultiplet then the free-energy scales as N 3. We also find the expectation value of a supersymmetric Wilson loop that wraps the equator. We demonstrate how to extract the effective couplings and reproduce results of Seiberg. Finally, we compare to results for the six-dimensional (2,0) theory derived using the AdS/CFT correspondence. We show that by choosing the hypermultiplet mass such that the supersymmetry is enhanced to N=2 , the Wilson loop result matches the analogous calculation using AdS/CFT. The free-energies differ by a rational fraction. This is a contribution to the review issue ‘Localization techniques in quantum field theories’ (ed Pestun and Zabzine) which contains 17 chapters available at [1].
Risk matrix model applied to the outsourcing of logistics' activities
Directory of Open Access Journals (Sweden)
Fouad Jawab
2015-09-01
Full Text Available Purpose: This paper proposes the application of the risk matrix model in the field of logistics outsourcing. Such an application can serve as the basis for decision making regarding the conduct of a risk management in the logistics outsourcing process and allow its prevention. Design/methodology/approach: This study is based on the risk management of logistics outsourcing in the field of the retail sector in Morocco. The authors identify all possible risks and then classify and prioritize them using the Risk Matrix Model. Finally, we have come to four possible decisions for the identified risks. The analysis was made possible through interviews and discussions with the heads of departments and agents who are directly involved in each outsourced activity. Findings and Originality/value: It is possible to improve the risk matrix model by proposing more personalized prevention measures according to each company that operates in the mass-market retailing. Originality/value: This study is the only one made in the process of logistics outsourcing in the retail sector in Morocco through Label’vie as a case study. First, we had identified as thorough as we could all possible risks, then we applied the Risk Matrix Model to sort them out in an ascending order of importance and criticality. As a result, we could hand out to the decision-makers the mapping for an effective control of risks and a better guiding of the process of risk management.
On the groundstate of octonionic matrix models in a ball
Boulton, L.; Garcia del Moral, M. P.; Restuccia, A.
2015-05-01
In this work we examine the existence and uniqueness of the groundstate of a SU (N) ×G2 octonionic matrix model on a bounded domain of RN. The existence and uniqueness argument of the groundstate wavefunction follows from the Lax-Milgram theorem. Uniqueness is shown by means of an explicit argument which is drafted in some detail.
On the groundstate of octonionic matrix models in a ball
Directory of Open Access Journals (Sweden)
L. Boulton
2015-05-01
Full Text Available In this work we examine the existence and uniqueness of the groundstate of a SU(N×G2 octonionic matrix model on a bounded domain of RN. The existence and uniqueness argument of the groundstate wavefunction follows from the Lax–Milgram theorem. Uniqueness is shown by means of an explicit argument which is drafted in some detail.
Mart ja Mari-Ann Susi taotlevad omanikena Concordia pankrotti / Andri Maimets
Maimets, Andri, 1979-
2003-01-01
Concordia Ülikooli rektor Mart Susi esitas kohtule avalduse, milles taotleb ülikooli pidanud Concordia Varahalduse OÜ pankroti väljakuulutamist. Vt. samas: Mari-Ann Susi õigustas ülikooli raha kasutamist
Matsumura, Tarojiro; Kuwatani, Tatsu; Masuda, Toshiaki
2017-06-01
We carried out statistical evaluations of two probability density functions for the microboudin palaeopiezometer using the Akaike information criterion (AIC) and the cross-validation (CV) technique. In terms of the relevant stress-transfer model, these functions are defined as the elastic matrix model and the Newtonian viscous matrix model, respectively. The AIC and CV techniques enable us to evaluate the relative quality of both models when applied to nine data sets collected from metachert samples containing tourmaline grains in a quartz matrix, collected from the East Pilbara Terrane, Western Australia. The results show that the elastic matrix model is the more appropriate probability density function for analysis of fracturing of tourmaline grains in a quartz matrix. This statistical evaluation shows the validity of the elastic matrix model for the microboudin palaeopiezometer when analysing such data sets.[Figure not available: see fulltext.
Modeling of 3-D Woven Ceramic Matrix Composites
Murthy, Pappu L. N.; Sullivan, Roy M.; Mital, Subodh K.
2003-01-01
Three different approaches are being pursued at the NASA Glenn Research Center to predict the nanostructural behavior of three-dimensional woven ceramic matrix composites. These are: a micromechanics-based approach using W-CEMCAN (Woven Ceramic Matrix Composite Analyzer), a laminate analogy method and a structural frame approach (based on the finite element method). All three techniques are applied to predict the thermomechanical properties of a three-dimensional woven angle interlock C/SiC composite. The properties are predicted for room temperature and 1100 C and the predicted properties are compared to measurements. General observations regarding the three approaches for three-dimensional composite modeling are discussed.
Klein, A.A.B.; Melard, G.; Zahaf, T.
2000-01-01
The Fisher information matrix is of fundamental importance for the analysis of parameter estimation of time series models. In this paper the exact information matrix of a multivariate Gaussian time series model expressed in state space form is derived. A computationally efficient procedure is used
Modelling of packet traffic with matrix analytic methods
DEFF Research Database (Denmark)
Andersen, Allan T.
1995-01-01
network services i.e. 800 and 900 calls and advanced mobile communication services. The Markovian Arrival Process (MAP) has been used as a versatile tool to model the packet arrival process. Applying the MAP facilitates the use of Matrix Analytic methods to obtain performance measures associated......-scales. In this study we show that 8-16 state MAPs are able to capture this very variable behaviour over several timescales. The queueing behaviour of these MAPs has been analyzed with Matrix Analytic methods. The results correspond to those obtained by trace driven simulations of measured LAN traffic. It is shown...... process. A heuristic formula for the tail behaviour of a single server queue fed by a superposition of renewal processes has been evaluated. The evaluation was performed by applying Matrix Analytic methods. The heuristic formula has applications in the Call Admission Control (CAC) procedure of the future...
H∞ /H2 model reduction through dilated linear matrix inequalities
DEFF Research Database (Denmark)
Adegas, Fabiano Daher; Stoustrup, Jakob
2012-01-01
This paper presents sufficient dilated linear matrix inequalities (LMI) conditions to the $H_{infty}$ and $H_{2}$ model reduction problem. A special structure of the auxiliary (slack) variables allows the original model of order $n$ to be reduced to an order $r=n/s$ where $n,r,s in field{N}$. Arb......This paper presents sufficient dilated linear matrix inequalities (LMI) conditions to the $H_{infty}$ and $H_{2}$ model reduction problem. A special structure of the auxiliary (slack) variables allows the original model of order $n$ to be reduced to an order $r=n/s$ where $n,r,s in field...... not satisfactorily approximates the original system, an iterative algorithm based on dilated LMIs is proposed to significantly improve the approximation bound. The effectiveness of the method is accessed by numerical experiments. The method is also applied to the $H_2$ order reduction of a flexible wind turbine...
Stability of the matrix model in operator interpretation
Directory of Open Access Journals (Sweden)
Katsuta Sakai
2017-12-01
Full Text Available The IIB matrix model is one of the candidates for nonperturbative formulation of string theory, and it is believed that the model contains gravitational degrees of freedom in some manner. In some preceding works, it was proposed that the matrix model describes the curved space where the matrices represent differential operators that are defined on a principal bundle. In this paper, we study the dynamics of the model in this interpretation, and point out the necessity of the principal bundle from the viewpoint of the stability and diffeomorphism invariance. We also compute the one-loop correction which yields a mass term for each field due to the principal bundle. We find that the stability is not violated.
Automatic Generation of Matrix Element Derivatives for Tight Binding Models
Alin M. Elena; Meister, Matthias
2005-01-01
Tight binding (TB) models are one approach to the quantum mechanical many particle problem. An important role in TB models is played by hopping and overlap matrix elements between the orbitals on two atoms, which of course depend on the relative positions of the atoms involved. This dependence can be expressed with the help of Slater-Koster parameters, which are usually taken from tables. Recently, a way to generate these tables automatically was published. If TB approaches are applied to sim...
Topological σ Models and Large N Matrix Integral
Eguchi, Tohru; Hori, Kentaro; Yang, Sung-Kil
In this paper we describe in some detail the representation of the topological CP1 model in terms of a matrix integral which we have introduced in a previous article. We first discuss the integrable structure of the CP1 model and show that it is governed by an extension of the one-dimensional Toda hierarchy. We then introduce a matrix model which reproduces the sum over holomorphic maps from arbitrary Riemann surfaces onto CP1. We compute intersection numbers on the moduli space of curves using a geometrical method and show that the results agree with those predicted by the matrix model. We also develop a Landau-Ginzburg (LG) description of the CP1 model using a superpotential eX + et0,Q e-X given by the Lax operator of the Toda hierarchy (X is the LG field and t0,Q is the coupling constant of the Kähler class). The form of the superpotential indicates the close connection between CP1 and N=2 supersymmetric sine-Gordon theory which was noted sometime ago by several authors. We also discuss possible generalizations of our construction to other manifolds and present an LG formulation of the topological CP2 model.
Analytical model for force prediction when machining metal matrix composites
Sikder, Snahungshu
Metal Matrix Composites (MMC) offer several thermo-mechanical advantages over standard materials and alloys which make them better candidates in different applications. Their light weight, high stiffness, and strength have attracted several industries such as automotive, aerospace, and defence for their wide range of products. However, the wide spread application of Meal Matrix Composites is still a challenge for industry. The hard and abrasive nature of the reinforcement particles is responsible for rapid tool wear and high machining costs. Fracture and debonding of the abrasive reinforcement particles are the considerable damage modes that directly influence the tool performance. It is very important to find highly effective way to machine MMCs. So, it is important to predict forces when machining Metal Matrix Composites because this will help to choose perfect tools for machining and ultimately save both money and time. This research presents an analytical force model for predicting the forces generated during machining of Metal Matrix Composites. In estimating the generated forces, several aspects of cutting mechanics were considered including: shearing force, ploughing force, and particle fracture force. Chip formation force was obtained by classical orthogonal metal cutting mechanics and the Johnson-Cook Equation. The ploughing force was formulated while the fracture force was calculated from the slip line field theory and the Griffith theory of failure. The predicted results were compared with previously measured data. The results showed very good agreement between the theoretically predicted and experimentally measured cutting forces.
Liu, Yang; The ATLAS collaboration
2017-01-01
Supersymmetry (SUSY) is a well motivated extension of the Standard Model (SM) that postulates the existence of a superpartner for each SM particle. A search for strongly produced SUSY particles decaying to a pair of two isolated \\textbf{same-sign leptons (SS)} or \\textbf{three leptons (3L)} has been carried out using the complete data set collected by the ATLAS experiment in 2015-16 at 13 TeV ($36.5 fb^{-1}$). The analysis benefits from a low SM background and uses looser kinematic requirements compared to other beyond the SM (BSM) searches which increases its sensitivity to scenarios with small mass differences between the SUSY particles, or in which R-parity is not conserved. The results are interpreted in the context of \\textbf{R-parity conserving (RPC)} or \\textbf{R-parity violating (RPV)} simplified signal models
Lepton Flavor Violation in SUSY-SO(10) with Predictive Yukawa Texture
Gomez, Mario E.; Goldberg, Haim
1995-01-01
We analyze the scalar lepton mass matrices in a supersymmetric SO(10) grand unified model with soft SUSY breaking terms generated at Planck scale and a Georgi-Jarslkog Yukawa texture at GUT scale induced by higher dimensional operators. This model predicts lepton flavor violation. The predictive features of the Georgi-Jarlskog texture are used to estimate branching ratios for the radiative decays $e_{a} \\rightarrow e_{b}+\\gamma,$ and we find rates that could provide an experimental test for t...
Matrix model of QCD: Edge localized glueballs and phase transitions
Acharyya, Nirmalendu; Balachandran, A. P.
2017-10-01
In a matrix model of pure SU(2) Yang-Mills theory, boundaries emerge in the space of Mat3(R ) and the Hamiltonian requires boundary conditions. We show the existence of edge localized glueball states that can have negative energies. These edge levels can be lifted to positive energies if the gluons acquire a London-like mass. This suggests a new phase of QCD with an incompressible bulk.
Dependency structure matrix modelling for stakeholder value networks
Feng, Wen; Crawley, Edward F.; de Weck, Olivier L.; Keller, Rene; Robinson, Bob
2010-01-01
This paper develops a qualitative/quantitative network approach, namely a “Stakeholder Value Network”, to understand the impacts of both direct and indirect relationships between stakeholders on the success of large engineering projects. Specifically, this paper explores the feasibility and benefit of applying the Dependency Structure Matrix (DSM) as the modelling platform for Stakeholder Value Networks. Further, an efficient algorithm is designed for computing indirect stakeholder influence ...
On reducibility and ergodicity of population projection matrix models
DEFF Research Database (Denmark)
Stott, Iain; Townley, Stuart; Carslake, David
2010-01-01
structure used in the population projection). In our sample of published PPMs, 15·6% are non-ergodic. 3. This presents a problem: reducible–ergodic models often defy biological rationale in their description of the life cycle but may or may not prove problematic for analysis as they often behave similarly...... of reducibility in published PPMs, with significant implications for the predictive power of such models in many cases. We suggest that as a general rule, reducibility of PPM models should be avoided. However, we provide a guide to the pertinent analysis of reducible matrix models, largely based upon whether...... from all stages to all other stages) and therefore ergodic (whatever initial stage structure is used in the population projection, it will always exhibit the same stable asymptotic growth rate). 2. Evaluation of 652 PPM models for 171 species from the literature suggests that 24·7% of PPM models...
Neutrino Oscillations in an SO(10) SUSY GUT with $U(2)xU(1)^{n}$ Family Symmetry
Blazek, T; Tobe, K
2000-01-01
In a previous paper we analyzed fermion masses (focusing on neutrino masses and mixing angles) in an SO(10) SUSY GUT with U(2)$\\timesU(1)^n$ family symmetry. The model is "natural" containing all operators in the Lagrangian consistent with the states and their charges. With minimal family symmetry breaking vevs the model is also predictive giving a unique solution to atmospheric (with maximal $\
Density matrix Monte Carlo modeling of quantum cascade lasers
Jirauschek, Christian
2017-10-01
By including elements of the density matrix formalism, the semiclassical ensemble Monte Carlo method for carrier transport is extended to incorporate incoherent tunneling, known to play an important role in quantum cascade lasers (QCLs). In particular, this effect dominates electron transport across thick injection barriers, which are frequently used in terahertz QCL designs. A self-consistent model for quantum mechanical dephasing is implemented, eliminating the need for empirical simulation parameters. Our modeling approach is validated against available experimental data for different types of terahertz QCL designs.
Results from GRACE/SUSY at one-loop
Indian Academy of Sciences (India)
3Seikei University, Musashino, Tokyo 180-8633, Japan. 4Meiji Gakuin University, Totsuka, Yokohama 244-8539, Japan. 5The Graduate University for Advanced Studies, Hayama, Kanagawa 240-0193, Japan. ∗E-mail: yasui@tmc-ipd.ac.jp. Abstract. We report the recent development on the SUSY calculations with the help.
DarkSUSY: Computing Supersymmetric Dark Matter Properties Numerically
Energy Technology Data Exchange (ETDEWEB)
Gondolo, P.
2004-07-16
The question of the nature of the dark matter in the Universe remains one of the most outstanding unsolved problems in basic science. One of the best motivated particle physics candidates is the lightest supersymmetric particle, assumed to be the lightest neutralino - a linear combination of the supersymmetric partners of the photon, the Z boson and neutral scalar Higgs particles. Here we describe DarkSUSY, a publicly-available advanced numerical package for neutralino dark matter calculations. In DarkSUSY one can compute the neutralino density in the Universe today using precision methods which include resonances, pair production thresholds and coannihilations. Masses and mixings of supersymmetric particles can be computed within DarkSUSY or with the help of external programs such as FeynHiggs, ISASUGRA and SUSPECT. Accelerator bounds can be checked to identify viable dark matter candidates. DarkSUSY also computes a large variety of astrophysical signals from neutralino dark matter, such as direct detection in low-background counting experiments and indirect detection through antiprotons, antideuterons, gamma-rays and positrons from the Galactic halo or high-energy neutrinos from the center of the Earth or of the Sun. Here we describe the physics behind the package. A detailed manual will be provided with the computer package.
Modeling of matrix acidizing process under reservoir conditions
Turegeldieva, Karlygash; Assilbekov, Bakhytzhan; Zhapbasbayev, Uzak; Zolotukhin, Anatoly; Bekibaev, Timur; Kenzhebekov, Nurlan; Gubkin Russian State University of oil; gas Collaboration
2013-11-01
Effectiveness of the process depends on the parameters: well choice, geological structure of the reservoir, definition of physical and chemical properties of rocks and fluids, agent choice. There are different mathematical models of the matrix acidizing, including the two scale model. These models describe the process in the core scale and Darcy scale, i.e. in an area with dimensions of several centimeters. It leads to the main problem - how to use these models to the near wellbore scale under reservoir conditions. Some authors have increased the dimensions of the cores in numerical simulations and investigated the influence of the core dimensions to acidizing process. In this paper effort to indirectly solve this problem made. It based on boundary conditions alteration and simultaneous solution of matrix acidizing in damaged zone and reservoir fluid flow models. Furthermore in this work the criterion of the acid injection shut down for optimal breakthrough volume calculation was modified. Influence of boundary conditions on near well-bore zone treatment process was investigated. Science Committee of Ministry of Education and Science of Republic of Kazakhstan.
Resonances and antibound states for the Pöschl–Teller potential: Ladder operators and SUSY partners
Energy Technology Data Exchange (ETDEWEB)
Çevik, D., E-mail: cevikdogukan@gmail.com [Department of Physics, Faculty of Science, Ankara University, 06100 Ankara (Turkey); Gadella, M., E-mail: manuelgadella1@gmail.com [Departamento de Física Teórica, Atómica y Óptica and IMUVA, Universidad de Valladolid, E-47011 Valladolid (Spain); Kuru, Ş., E-mail: kuru@science.ankara.edu.tr [Department of Physics, Faculty of Science, Ankara University, 06100 Ankara (Turkey); Negro, J., E-mail: jnegro@fta.uva.es [Departamento de Física Teórica, Atómica y Óptica and IMUVA, Universidad de Valladolid, E-47011 Valladolid (Spain)
2016-04-22
We analyze the one dimensional scattering produced by all variations of the Pöschl–Teller potential, i.e., potential well, low and high barriers. The transmission coefficients of Pöschl–Teller well and low barrier potentials have an infinite number of simple poles corresponding to bound and antibound states. However, the Pöschl–Teller high barrier potential shows an infinite number of resonance poles. We have constructed ladder operators connecting wave functions for bound and antibound states as well as for resonance states. Finally, using wave functions of these states, we provide some examples of supersymmetric partners of the Pöschl–Teller Hamiltonian. - Highlights: • Poles of the scattering matrix of Pöschl–Teller potentials are obtained. • These poles are associated to bound, antibound and resonance states. • Ladder operators connecting these states are constructed. • Susy partners using antibound and resonance states are computed.
The multitrace matrix model: An alternative to Connes NCG and IKKT model in 2 dimensions
Energy Technology Data Exchange (ETDEWEB)
Ydri, Badis, E-mail: ydri@stp.dias.ie
2016-12-10
We present a new multitrace matrix model, which is a generalization of the real quartic one matrix model, exhibiting dynamical emergence of a fuzzy two-sphere and its non-commutative gauge theory. This provides a novel and a much simpler alternative to Connes non-commutative geometry and to the IKKT matrix model for emergent geometry in two dimensions. However, in higher dimensions this mechanism is not known to exist and the systematic frameworks of NCG and IKKT are expected to hold sway.
Higher rank ABJM Wilson loops from matrix models
Energy Technology Data Exchange (ETDEWEB)
Cookmeyer, Jonathan [Haverford College,370 Lancaster Avenue, Haverford, PA, 19041 (United States); Liu, James T. [Michigan Center for Theoretical Physics, Department of Physics, University of Michigan,450 Church Street, Ann Arbor, MI, 48109 (United States); Zayas, Leopoldo A. Pando [The Abdus Salam International Centre for Theoretical Physics,Strada Costiera 11, Trieste, 34014 (Italy)
2016-11-21
We compute the vacuum expectation values of 1/6 supersymmetric Wilson loops in higher dimensional representations of the gauge group in ABJM theory. We present results for the m-symmetric and m-antisymmetric representations by exploiting standard matrix model techniques. At leading order, in the saddle point approximation, our expressions reproduce holographic results from both D6 and D2 branes corresponding to the antisymmetric and symmetric representations, respectively. We also compute 1/N corrections to the leading saddle point results.
THE BONUS-MALUS SYSTEM MODELLING USING THE TRANSITION MATRIX
Directory of Open Access Journals (Sweden)
SANDRA TEODORESCU
2012-05-01
Full Text Available The motor insurance is an important branch of non-life insurance in many countries; in some of them, coming first in total premium income category (in Romania, for example. The Bonus-Malus system implementation is one of the solutions chosen by the insurance companies in order to increase the efficiency in the motor insurance domain. This system has been recently introduced by the Romanian insurers as well. In this paper I present the means for modelling the bonus-malus system using the transition matrix.
Three-Body Nuclear Forces from a Matrix Model
Hashimoto, Koji
2010-01-01
We compute three-body nuclear forces at short distances by using the nuclear matrix model of holographic QCD proposed in our previous paper with P. Yi. We find that the three-body forces at short distances are repulsive for (a) aligned three neutrons with averaged spins, and (b) aligned proton-proton-neutron / proton-neutron-neutron. These indicate that in dense states of neutrons such as cores of neutron stars, or in Helium-3 / tritium nucleus, the repulsive forces are larger than the ones estimated from two-body forces only.
Approximate State Transition Matrix and Secular Orbit Model
Directory of Open Access Journals (Sweden)
M. P. Ramachandran
2015-01-01
Full Text Available The state transition matrix (STM is a part of the onboard orbit determination system. It is used to control the satellite’s orbital motion to a predefined reference orbit. Firstly in this paper a simple orbit model that captures the secular behavior of the orbital motion in the presence of all perturbation forces is derived. Next, an approximate STM to match the secular effects in the orbit due to oblate earth effect and later in the presence of all perturbation forces is derived. Numerical experiments are provided for illustration.
Non-simplified SUSY. {tau}-coannihilation at LHC and ILC
Energy Technology Data Exchange (ETDEWEB)
Berggren, M.; Cakir, A.; Krueger, D.; List, J.; Lobanov, A.; Melzer-Pellmann, I.A.
2013-07-15
Simplified models have become a widely used and important tool to cover the more diverse phenomenology beyond constrained SUSY models. However, they come with a substantial number of caveats themselves, and great care needs to be taken when drawing conclusions from limits based on the simplified approach. To illustrate this issue with a concrete example, we examine the applicability of simplified model results to a series of full SUSY model points which all feature a small {tau} -LSP mass difference, and are compatible with electroweak and flavor precision observables as well as current LHC results. Various channels have been studied using the Snowmass Combined LHC detector implementation in the Delphes simulation package, as well as the Letter of Intent or Technical Design Report simulations of the ILD detector concept at the ILC. We investigated both the LHC and ILC capabilities for discovery, separation and identification of all parts of the spectrum. While parts of the spectrum would be discovered at the LHC, there is substantial room for further discoveries and property determination at the ILC.
Chiral condensate in the Schwinger model with matrix product operators
Energy Technology Data Exchange (ETDEWEB)
Banuls, Mari Carmen [Max-Planck-Institut fuer Quantenoptik (MPQ), Garching (Germany); Cichy, Krzysztof [Frankfurt Univ. (Germany). Inst. fuer Theoretische Physik; Poznan Univ. (Poland). Faculty of Physics; Jansen, Karl [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany). John von Neumann-Inst. fuer Computing NIC; Saito, Hana [Tsukuba Univ. (Japan). Center for Computational Sciences
2016-03-15
Tensor network (TN) methods, in particular the Matrix Product States (MPS) ansatz, have proven to be a useful tool in analyzing the properties of lattice gauge theories. They allow for a very good precision, much better than standard Monte Carlo (MC) techniques for the models that have been studied so far, due to the possibility of reaching much smaller lattice spacings. The real reason for the interest in the TN approach, however, is its ability, shown so far in several condensed matter models, to deal with theories which exhibit the notorious sign problem in MC simulations. This makes it prospective for dealing with the non-zero chemical potential in QCD and other lattice gauge theories, as well as with real-time simulations. In this paper, using matrix product operators, we extend our analysis of the Schwinger model at zero temperature to show the feasibility of this approach also at finite temperature. This is an important step on the way to deal with the sign problem of QCD. We analyze in detail the chiral symmetry breaking in the massless and massive cases and show that the method works very well and gives good control over a broad range of temperatures, essentially from zero to infinite temperature.
SUSY-QCD Effects in Top Quark Pair Production in Association with a Gluon at the ILC
Zhang, Yan-Ming; Liu, Ning
2015-08-01
Given the null results of searches for new physics at the LHC, we investigate the one-loop effects SUSY QCD in the process e^ + e^ - \\to t\\bar tg at the ILC in Minimal Supersymmetric Standard Model (MSSM). We find that the relative SUSY-QCD corrections to the cross section of e^ + e^ - \\to t\\bar tg can maximally reach 6.5%(3.2%) at the ILC with \\sqrt s = 1000 GeV when m\\bar t1 = 313.4 GeV and m\\bar g = 500≤ft( {1500} \\right) GeV. Supported by the National Natural Science Foundation of China (NNSFC) under Grant Nos. 11305049, 11275057, and 11405047, by Specialized Research Fund for the Doctoral Program of Higher Education under Grant No. 20134104120002 and by the Startup Foundation for Doctors of Henan Normal University under Grant No. 11112
Matrix Model for Choosing Green Marketing Sustainable Strategic Alternatives
Directory of Open Access Journals (Sweden)
Cătălina Sitnikov
2015-08-01
Full Text Available Green marketing examines the symbiotic role played by marketing in ensuring sustainable business, exploring issues concerning the environment and the way strategic decisions can influence it. At present, the environmental issues concern more and more the competitive approach any organization can implement. Based on this approach, organizations can gain competitive advantage by managing environmental variables and by developing and implementing green marketing strategies. Considering the importance and impact of green marketing, by using theoretical concepts and defining a set of research directions, the paper and the research conducted were focused on creating a matrix model for choosing the optimal green marketing strategy, oriented towards competitive advantage. The model is based on the correlation that can be established among the generic strategies of competitive advantage, the variables of extended marketing mix (7Ps and the green marketing strategy matrix. There are also analyzed the implications that may be generated within a company by the adoption of a green marketing strategy and its role in promoting the environmental benefits of products.
Leptogenesis scenarios for natural SUSY with mixed axion-higgsino dark matter
Energy Technology Data Exchange (ETDEWEB)
Bae, Kyu Jung [Department of Physics and Astronomy, University of Oklahoma,Norman, OK 73019 (United States); Department of Physics, University of Tokyo,Bunkyo-ku, Tokyo 113-0033 (Japan); Baer, Howard; Serce, Hasan; Zhang, Yi-Fan [Department of Physics and Astronomy, University of Oklahoma,Norman, OK 73019 (United States)
2016-01-07
Supersymmetric models with radiatively-driven electroweak naturalness require light higgsinos of mass ∼100–300 GeV. Naturalness in the QCD sector is invoked via the Peccei-Quinn (PQ) axion leading to mixed axion-higgsino dark matter. The SUSY DFSZ axion model provides a solution to the SUSY μ problem and the Little Hierarchy μ≪m{sub 3/2} may emerge as a consequence of a mismatch between PQ and hidden sector mass scales. The traditional gravitino problem is now augmented by the axino and saxion problems, since these latter particles can also contribute to overproduction of WIMPs or dark radiation, or violation of BBN constraints. We compute regions of the T{sub R} vs. m{sub 3/2} plane allowed by BBN, dark matter and dark radiation constraints for various PQ scale choices f{sub a}. These regions are compared to the values needed for thermal leptogenesis, non-thermal leptogenesis, oscillating sneutrino leptogenesis and Affleck-Dine leptogenesis. The latter three are allowed in wide regions of parameter space for PQ scale f{sub a}∼10{sup 10}–10{sup 12} GeV which is also favored by naturalness: f{sub a}∼√(μM{sub P}/λ{sub μ})∼10{sup 10}–10{sup 12} GeV. These f{sub a} values correspond to axion masses somewhat above the projected ADMX search regions.
Reinhardt, James W; Krakauer, Daniel A; Gooch, Keith J
2013-07-01
Using a top-down approach, an agent-based model was developed within NetLogo where cells and extracellular matrix (ECM) fibers were composed of multiple agents to create deformable structures capable of exerting, reacting to, and transmitting mechanical force. At the beginning of the simulation, long fibers were randomly distributed and cross linked. Throughout the simulation, imposed rules allowed cells to exert traction forces by extending pseudopodia, binding to fibers and pulling them towards the cell. Simulated cells remodeled the fibrous matrix to change both the density and alignment of fibers and migrated within the matrix in ways that are consistent with previous experimental work. For example, cells compacted the matrix in their pericellular regions much more than the average compaction experienced for the entire matrix (696% versus 21%). Between pairs of cells, the matrix density increased (by 92%) and the fibers became more aligned (anisotropy index increased from 0.45 to 0.68) in the direction parallel to a line connecting the two cells, consistent with the "lines of tension" observed in experiments by others. Cells migrated towards one another at an average rate of ∼0.5 cell diameters per 10,000 arbitrary units (AU); faster migration occurred in simulations where the fiber density in the intercellular area was greater. To explore the potential contribution of matrix stiffness gradients in the observed migration (i.e., durotaxis), the model was altered to contain a regular lattice of fibers possessing a stiffness gradient and just a single cell. In these simulations cells migrated preferentially in the direction of increasing stiffness at a rate of ∼2 cell diameter per 10,000 AU. This work demonstrates that matrix remodeling and durotaxis, both complex phenomena, might be emergent behaviors based on just a few rules that control how a cell can interact with a fibrous ECM.
Teaching Improvement Model Designed with DEA Method and Management Matrix
Montoneri, Bernard
2014-01-01
This study uses student evaluation of teachers to design a teaching improvement matrix based on teaching efficiency and performance by combining management matrix and data envelopment analysis. This matrix is designed to formulate suggestions to improve teaching. The research sample consists of 42 classes of freshmen following a course of English…
Misra, Aalok; Shukla, Pramod
2010-03-01
We consider type IIB large volume compactifications involving orientifolds of the Swiss Cheese Calabi-Yau WCP[1,1,1,6,9] with a single mobile space-time filling D3-brane and stacks of D7-branes wrapping the “big” divisor ΣB (as opposed to the “small” divisor usually done in the literature thus far) as well as supporting D7-brane fluxes. After reviewing our proposal of [1] (Misra and Shukla, 2010) for resolving a long-standing tension between large volume cosmology and phenomenology pertaining to obtaining a 10 GeV gravitino in the inflationary era and a TeV gravitino in the present era, and summarizing our results of [1] (Misra and Shukla, 2010) on soft supersymmetry breaking terms and open-string moduli masses, we discuss the one-loop RG running of the squark and slepton masses in mSUGRA-like models (using the running of the gaugino masses) to the EW scale in the large volume limit. Phenomenological constraints and some of the calculated soft SUSY parameters identify the D7-brane Wilson line moduli as the first two generations/families of squarks and sleptons and the D3-brane (restricted to the big divisor) position moduli as the two Higgses for MSSM-like models at TeV scale. We also discuss how the obtained open-string/matter moduli make it easier to impose FCNC constraints, as well as RG flow of off-diagonal squark mass(-squared) matrix elements.
Testing No-Scale F- SU (5): A 125 GeV Higgs boson and SUSY at the √{ s} = 8 TeV LHC
Li, Tianjun; Maxin, James A.; Nanopoulos, Dimitri V.; Walker, Joel W.
2012-11-01
We celebrate the recent Higgs discovery announcement with our experimental colleagues at the LHC and look forward to the implications that this success will bring to bear upon the continuing search for supersymmetry (SUSY). The model framework named No-Scale F- SU (5) possesses the rather unique capacity to provide a light CP-even Higgs boson mass in the favored 124-126 GeV window while simultaneously retaining a testably light SUSY spectrum that is consistent with emerging low-statistics excesses beyond the Standard Model expectation in the ATLAS and CMS multijet data. In this Letter we review the distinctive F- SU (5) mechanism that forges the physical 125 GeV Higgs boson and make a specific assessment of the ATLAS multijet SUSY search observables that may be expected for a 15 fb-1 delivery of 8 TeV data in this model context. Based on our Monte Carlo study, we anticipate that the enticing hints of a SUSY signal observed in the 7 TeV data could be amplified in the 8 TeV results. Moreover, if the existing signal is indeed legitimate, we project that the rendered gains in significance will be sufficient to conclusively rule out an alternative attribution to statistical fluctuation at that juncture.
Analysis of SUSY Heavy Higgs events at CLIC
Quevillon, J
2009-01-01
This paper reports the results of a study of the supersymmetric neutral heavy Higgs boson production channel e+e− → H◦A◦ → bb ̄bb ̄ at √s = 3 TeV. Reconstruction of data simulated at generator level shows a significant degradation of SUSY Heavy Higgs signal caused by γγ to hadrons background at s = 3 TeV. The importance of analysis procedures such as event cuts and transversal momentum cuts during jet-clustering to reduce the impact of the hadron background is underlined. Reconstruction at both the generator level and at the level of a full detector simulation forces us to introduce cuts to improve the quality of the results. This note describes a preliminary study of SUSY Heavy Higgs at CLIC - a more detailed paper on an extended study is in preparation.
SLAM, a Mathematica interface for SUSY spectrum generators
Energy Technology Data Exchange (ETDEWEB)
Marquard, Peter [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany); Zerf, Nikolai [Alberta Univ., Edmonton, AB (Canada). Dept. of Physics
2013-09-15
We present and publish a Mathematica package, which can be used to automatically obtain any numerical MSSM input parameter from SUSY spectrum generators, which follow the SLHA standard, like SPheno, SOFTSUSY or Suspect. The package enables a very comfortable way of numerical evaluations within the MSSM using Mathematica. It implements easy to use predefined high scale and low scale scenarios like mSUGRA or m{sub h}{sup max} and if needed enables the user to directly specify the input required by the spectrum generators. In addition it supports an automatic saving and loading of SUSY spectra to and from a SQL data base, avoiding the rerun of a spectrum generator for a known spectrum.
Search for compressed SUSY scenarios with the ATLAS detector
Maurer, Julien; The ATLAS collaboration
2017-01-01
Scenarios where multiple SUSY states are nearly degenerate in mass produce soft decay products, and they represent an experimental challenge for ATLAS. This talk presents recent results of analyses explicitly targeting such “compressed” scenarios with a variety of experimental techniques. All results make use of proton-proton collisions collected at a centre of mass of 13 TeV with the ATLAS detector.
SLAM, a Mathematica interface for SUSY spectrum generators
Marquard, Peter; Zerf, Nikolai
2014-03-01
We present and publish a Mathematica package, which can be used to automatically obtain any numerical MSSM input parameter from SUSY spectrum generators, which follow the SLHA standard, like SPheno, SOFTSUSY, SuSeFLAV or Suspect. The package enables a very comfortable way of numerical evaluations within the MSSM using Mathematica. It implements easy to use predefined high scale and low scale scenarios like mSUGRA or mhmax and if needed enables the user to directly specify the input required by the spectrum generators. In addition it supports an automatic saving and loading of SUSY spectra to and from a SQL data base, avoiding the rerun of a spectrum generator for a known spectrum. Catalogue identifier: AERX_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AERX_v1_0.html Program obtainable from: CPC Program Library, Queen’s University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 4387 No. of bytes in distributed program, including test data, etc.: 37748 Distribution format: tar.gz Programming language: Mathematica. Computer: Any computer where Mathematica version 6 or higher is running providing bash and sed. Operating system: Linux. Classification: 11.1. External routines: A SUSY spectrum generator such as SPheno, SOFTSUSY, SuSeFLAV or SUSPECT Nature of problem: Interfacing published spectrum generators for automated creation, saving and loading of SUSY particle spectra. Solution method: SLAM automatically writes/reads SLHA spectrum generator input/output and is able to save/load generated data in/from a data base. Restrictions: No general restrictions, specific restrictions are given in the manuscript. Running time: A single spectrum calculation takes much less than one second on a modern PC.
Search for compressed SUSY scenarios with the ATLAS detector
Maurer, Julien; The ATLAS collaboration
2017-01-01
Scenarios where multiple SUSY states are nearly degenerate in mass produce soft decay products, and they represent an experimental challenge for ATLAS. This contribution presented recent results of analyses explicitly targeting such ``compressed'' scenarios with a variety of experimental techniques. All results made use of proton-proton collisions collected at a centre-of-mass energy of 13 TeV with the ATLAS detector at the LHC.
Low-scale SUSY breaking and the (s)goldstino physics
Antoniadis, I.
2013-01-01
For a 4D N=1 supersymmetric model with a low SUSY breaking scale (f) and general Kahler potential K(Phi^i,Phi_j^*) and superpotential W(Phi^i) we study, in an effective theory approach, the relation of the goldstino superfield to the (Ferrara-Zumino) superconformal symmetry breaking chiral superfield X. In the presence of more sources of supersymmetry breaking, we verify the conjecture that the goldstino superfield is the (infrared) limit of X for zero-momentum and Lambda->\\infty. (Lambda is the effective cut-off scale). We then study the constraint X^2=0, which in the one-field case is known to decouple a massive sgoldstino and thus provide an effective superfield description of the Akulov-Volkov action for the goldstino. In the presence of additional fields that contribute to SUSY breaking we identify conditions for which X^2=0 remains valid, in the effective theory below a large but finite sgoldstino mass. The conditions ensure that the effective expansion (in 1/Lambda) of the initial Lagrangian is not in ...
Thermal evolution of the Schwinger model with matrix product operators
Energy Technology Data Exchange (ETDEWEB)
Banuls, M.C.; Cirac, J.I. [Max-Planck-Institut fuer Quantenoptik, Garching (Germany); Cichy, K. [Frankfurt am Main Univ. (Germany). Inst. fuer Theoretische Physik; Poznan Univ. (Poland). Faculty of Physics; DESY Zeuthen (Germany). John von Neumann-Institut fuer Computing (NIC); Jansen, K.; Saito, H. [DESY Zeuthen (Germany). John von Neumann-Institut fuer Computing (NIC)
2015-10-15
We demonstrate the suitability of tensor network techniques for describing the thermal evolution of lattice gauge theories. As a benchmark case, we have studied the temperature dependence of the chiral condensate in the Schwinger model, using matrix product operators to approximate the thermal equilibrium states for finite system sizes with non-zero lattice spacings. We show how these techniques allow for reliable extrapolations in bond dimension, step width, system size and lattice spacing, and for a systematic estimation and control of all error sources involved in the calculation. The reached values of the lattice spacing are small enough to capture the most challenging region of high temperatures and the final results are consistent with the analytical prediction by Sachs and Wipf over a broad temperature range.
Higgs, Binos and Gluinos: Split Susy within Reach
Energy Technology Data Exchange (ETDEWEB)
Alves, Daniele S.M.; Izaguirre, Eder; /SLAC /Stanford U., Phys. Dept.; Wacker, Jay G.; /SLAC /Stanford U., ITP
2012-09-14
Recent results from the LHC for the Higgs boson with mass between 142 GeV {approx}< m{sub h{sup 0}} {approx}< 147 GeV points to PeV-scale Split Supersymmetry. This article explores the consequences of a Higgs mass in this range and possible discovery modes for Split Susy. Moderate lifetime gluinos, with decay lengths in the 25 {micro}m to 10 yr range, are its imminent smoking gun signature. The 7TeV LHC will be sensitive to the moderately lived gluinos and trilepton signatures from direct electroweakino production. Moreover, the dark matter abundance may be obtained from annihilation through an s-channel Higgs resonance, with the LSP almost purely bino and mass m{sub {chi}{sub 1}{sup 0}} {approx_equal} 70 GeV. The Higgs resonance region of Split Susy has visible signatures in dark matter direct and indirect detection and electric dipole moment experiments. If the anomalies go away, the majority of Split Susy parameter space will be excluded.
A new Expert Finding model based on Term Correlation Matrix
Directory of Open Access Journals (Sweden)
Ehsan Pornour
2015-09-01
Full Text Available Due to the enormous volume of unstructured information available on the Web and inside organization, finding an answer to the knowledge need in a short time is difficult. For this reason, beside Search Engines which don’t consider users individual characteristics, Recommender systems were created which use user’s previous activities and other individual characteristics to help users find needed knowledge. Recommender systems usage is increasing every day. Expert finder systems also by introducing expert people instead of recommending information to users have provided this facility for users to ask their questions form experts. Having relation with experts not only causes information transition, but also with transferring experiences and inception causes knowledge transition. In this paper we used university professors academic resume as expert people profile and then proposed a new expert finding model that recommends experts to users query. We used Term Correlation Matrix, Vector Space Model and PageRank algorithm and proposed a new hybrid model which outperforms conventional methods. This model can be used in internet environment, organizations and universities that experts have resume dataset.
Matrix approach to land carbon cycle modeling: A case study with Community Land Model.
Huang, Yuanyuan; Lu, Xingjie; Shi, Zheng; Lawrence, David; Koven, Charles; Xia, Jianyang; Du, Zhenggang; Kluzek, Erik; Luo, Yiqi
2017-10-20
The terrestrial carbon (C) cycle has been commonly represented by a series of C balance equations to track C influxes into and effluxes out of individual pools in earth system models (ESMs). This representation matches our understanding of C cycle processes well but makes it difficult to track model behaviors. It is also computationally expensive, limiting the ability to conduct comprehensive parametric sensitivity analyses. To overcome these challenges, we have developed a matrix approach, which reorganizes the C balance equations in the original ESM into one matrix equation without changing any modeled C cycle processes and mechanisms. We applied the matrix approach to the Community Land Model (CLM4.5) with vertically resolved biogeochemistry. The matrix equation exactly reproduces litter and soil organic carbon (SOC) dynamics of the standard CLM4.5 across different spatial-temporal scales. The matrix approach enables effective diagnosis of system properties such as C residence time and attribution of global change impacts to relevant processes. We illustrated, for example, the impacts of CO2 fertilization on litter and SOC dynamics can be easily decomposed into the relative contributions from C input, allocation of external C into different C pools, nitrogen regulation, altered soil environmental conditions, and vertical mixing along the soil profile. In addition, the matrix tool can accelerate model spin-up, permit thorough parametric sensitivity tests, enable pool-based data assimilation, and facilitate tracking and benchmarking of model behaviors. Overall, the matrix approach can make a broad range of future modeling activities more efficient and effective. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.
Simulating generic spin-boson models with matrix product states
Wall, Michael L.; Safavi-Naini, Arghavan; Rey, Ana Maria
2016-11-01
The global coupling of few-level quantum systems ("spins") to a discrete set of bosonic modes is a key ingredient for many applications in quantum science, including large-scale entanglement generation, quantum simulation of the dynamics of long-range interacting spin models, and hybrid platforms for force and spin sensing. We present a general numerical framework for treating the out-of-equilibrium dynamics of such models based on matrix product states. Our approach applies for generic spin-boson systems: it treats any spatial and operator dependence of the two-body spin-boson coupling and places no restrictions on relative energy scales. We show that the full counting statistics of collective spin measurements and infidelity of quantum simulation due to spin-boson entanglement, both of which are difficult to obtain by other techniques, are readily calculable in our approach. We benchmark our method using a recently developed exact solution for a particular spin-boson coupling relevant to trapped ion quantum simulators. Finally, we show how decoherence can be incorporated within our framework using the method of quantum trajectories, and study the dynamics of an open-system spin-boson model with spatially nonuniform spin-boson coupling relevant for trapped atomic ion crystals in the presence of molecular ion impurities.
Multiscale modeling of PVDF matrix carbon fiber composites
Greminger, Michael; Haghiashtiani, Ghazaleh
2017-06-01
Self-sensing carbon fiber reinforced composites have the potential to enable structural health monitoring that is inherent to the composite material rather than requiring external or embedded sensors. It has been demonstrated that a self-sensing carbon fiber reinforced polymer composite can be created by using the piezoelectric polymer polyvinylidene difluoride (PVDF) as the matrix material and using a Kevlar layer to separate two carbon fiber layers. In this configuration, the electrically conductive carbon fiber layers act as electrodes and the Kevlar layer acts as a dielectric to prevent the electrical shorting of the carbon fiber layers. This composite material has been characterized experimentally for its effective d 33 and d 31 piezoelectric coefficients. However, for design purposes, it is desirable to obtain a predictive model of the effective piezoelectric coefficients for the final smart composite material. Also, the inverse problem can be solved to determine the degree of polarization obtained in the PVDF material during polarization by comparing the effective d 33 and d 31 values obtained in experiment to those predicted by the finite element model. In this study, a multiscale micromechanics and coupled piezoelectric-mechanical finite element modeling approach is introduced to predict the mechanical and piezoelectric performance of a plain weave carbon fiber reinforced PVDF composite. The modeling results show good agreement with the experimental results for the mechanical and electrical properties of the composite. In addition, the degree of polarization of the PVDF component of the composite is predicted using this multiscale modeling approach and shows that there is opportunity to drastically improve the smart composite’s performance by improving the polarization procedure.
Physical characterization and kinetic modelling of matrix tablets of ...
African Journals Online (AJOL)
Purpose: To design controlled release ketorolac tromethamol (KT) matrix tablets for increased drug bioavailability. Methods: Waxes (Compritol® ATO 888, Precirol® ATO 5 and stearic acid - SA) and polymers (hydroxypropyl methylcellulose - HPMC and xanthan gum - XG) were used in the preparation of the matrix tablets at ...
DEFF Research Database (Denmark)
Terp, G E; Christensen, I T; Jørgensen, Flemming Steen
2000-01-01
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...
Stage-structured matrix models for organisms with non-geometric development times
Andrew Birt; Richard M. Feldman; David M. Cairns; Robert N. Coulson; Maria Tchakerian; Weimin Xi; James M. Guldin
2009-01-01
Matrix models have been used to model population growth of organisms for many decades. They are popular because of both their conceptual simplicity and their computational efficiency. For some types of organisms they are relatively accurate in predicting population growth; however, for others the matrix approach does not adequately model...
Mart ja Mari-Ann Susi taotlevad omanikena Concordia pankrotti / Andri Maimets
Maimets, Andri
2003-01-01
Concordia Ülikooli rektori kohast loobunud Mart Susi ning prorektori ametikohalt lahkunud Mari-Ann Susi taotlevad neile kuuluvat ülikooli pidanud miljonivõlgades firma pankrotti. Hiljuti loodi õppejõududest, tudengitest js töötajatest mittetulundusühing Concordia Akadeemiline Ühisus (CAU), selle nõukogu esimees on Hagi Šein
D-brane probes in the matrix model
Energy Technology Data Exchange (ETDEWEB)
Ferrari, Frank, E-mail: frank.ferrari@ulb.ac.be
2014-03-15
Recently, a new approach to large N gauge theories, based on a generalization of the concept of D-brane probes to any gauge field theory, was proposed. In the present note, we compute the probe action in the one matrix model with a quartic potential. This allows to illustrate several non-trivial aspects of the construction in an exactly solvable set-up. One of our main goal is to test the bare bubble approximation. The approximate free energy found in this approximation, which can be derived from a back-of-an-envelope calculation, matches the exact result for all values of the 't Hooft coupling with a surprising accuracy. Another goal is to illustrate the remarkable properties of the equivariant partial gauge-fixing procedure, which is at the heart of the formalism. For this we use a general ξ-gauge to compute the brane action. The action depends on ξ in a very non-trivial way, yet we show explicitly that its critical value does not and coincides with twice the free energy, as required by general consistency. This is made possible by a phenomenon of ghost condensation and the spontaneous breaking of the equivariant BRST symmetry.
Hybrid Model for Homogenization of the Elastoplastic Properties of Isotropic Matrix Composites
Fedotov, A. F.
2017-07-01
A hybrid homogenization model for calculating the effective elastoplastic properties of isotropic matrix composites is suggested. The hybrid model combines the continuous deformation models of heterogeneous solid and porous materials. A distinctive feature of the model is the calculation of concentration coefficients of the average Hill strains in terms of the effective volumes of strain averaging. The effective volumes of averaging are determined by solving the boundary-value problem on plastic deformation of a simplified structural model of a two-phase composite considering the porous state of matrix. A comparison of calculation results with experimental data upon constructing deformation diagrams for polymer-matrix and metal-matrix composites is carried out. The possibility of changing the properties of the metal matrix in producing composites is mentioned. Therefore, the adequacy of analytical models greatly depends on the accuracy of identification of material constants of the matrix. On the whole, the new model described the plastic deformation of matrix composites more accurately than the Mori-Tanaka model. The analytical model proposed has a simpler sampling scheme, a simple computation algorithm, and ensured the same calculation accuracy for the deformation diagram of an aluminum-matrix composite as the numerical finite-element model created by the ABAQUS software.
Micromechanism Based Modeling of Structural Life in Metal Matrix Composites
National Research Council Canada - National Science Library
Allen, David
1997-01-01
.... These achievements include: (1) life prediction of continuous fiber metal matrix composites; (2) the influence of heat treatment on the mechanical properties and damage development in a SiC/Ti-15-3 MMC; (3...
Nonperturbative effects and nonperturbative definitions in matrix models and topological strings
Marino, Marcos
2008-01-01
We develop techniques to compute multi-instanton corrections to the 1/N expansion in matrix models described by orthogonal polynomials. These techniques are based on finding trans-series solutions, i.e. formal solutions with exponentially small corrections, to the recursion relations characterizing the free energy. We illustrate this method in the Hermitian, quartic matrix model, and we provide a detailed description of the instanton corrections in the Gross-Witten-Wadia (GWW) unitary matrix ...
{{{ N}}=2} SUSY gauge theories on S4
Hosomichi, Kazuo
2017-11-01
We review exact results in {{ N}}=2 supersymmetric gauge theories defined on S 4 and its deformation. We first summarize the construction of rigid SUSY theories on curved backgrounds based on off-shell supergravity, then explain how to apply the localization principle to supersymmetric path integrals. Closed formulae for partition function as well as expectation values of non-local BPS observables are presented. This is a contribution to the review issue ‘Localization techniques in quantum field theories’ (ed V Pestun and M Zabzine) which contains 17 chapters available at [1].
Searches for SUSY in leptons+jets+MET final states
Hoermann, Natascha
2009-01-01
Session:Higgs and New Physics If supersymmetry would manifest itself at a low mass scale it might be found already in the early phase of the LHC operation. Generic signatures for supersymmetry in pp-collisions consist of high jet multiplicity, large missing transverse energy (MET) as well as leptons in the final state. The presence of charged leptons makes these signature more robust and therefore facilitates their application in early data-taking. This talk will review the CMS search strategy and prospects for a SUSY discovery in the single lepton and di-lepton final states.
López, Jorge L; Zichichi, A
1994-01-01
The determination of the most straightforward evidence for the existence of the Superworld requires a guide for non-experts (especially experimental physicists) for them to make their own judgement on the value of such predictions. For this purpose we review the most basic results of Super-Grand unification in a simple and clear way. We focus the attention on two specific models and their predictions. These two models represent an example of a direct comparison between a traditional unified-theory and a string-inspired approach to the solution of the many open problems of the Standard Model. We emphasize that viable models must satisfy {\\em all} available experimental constraints and be as simple as theoretically possible. The two well defined supergravity models, $SU(5)$ and $SU(5)\\times U(1)$, can be described in terms of only a few parameters (five and three respectively) instead of the more than twenty needed in the MSSM model, \\ie, the Minimal Supersymmetric extension of the Standard Model. A case of spe...
Nonperturbative Effects and the Large-Order Behavior of Matrix Models and Topological Strings
Marino, Marcos; Weiss, Marlene
2007-01-01
This work addresses nonperturbative effects in both matrix models and topological strings, and their relation with the large-order behavior of perturbation theory. We study instanton configurations in generic one-cut matrix models, obtaining explicit results for the one-instanton amplitude at both one and two loops. The holographic description of topological strings in terms of matrix models implies that our nonperturbative results also apply to topological strings on toric Calabi-Yau manifolds. This yields very precise predictions for the large-order behavior of the perturbative genus expansion, both in conventional matrix models and in topological string theory. We test these predictions in detail in various examples, including the quartic matrix model, topological strings on the local curve, and Hurwitz theory. In all these cases we provide extensive numerical checks which heavily support our nonperturbative analytical results. Moreover, since all these models have a critical point describing two-dimension...
SUSY Searches in the ATLAS Experiment
Lee JR, Lawrence; The ATLAS collaboration
2015-01-01
Recent results from the ATLAS experiment at the LHC in the search for supersymmetry are presented. A focus is placed on searches requiring nonstandard techniques in particularly challenging final states. All searches presented here analyze $pp$ collisions with $\\sqrt{s}=8$~TeV collected in 2012. Within these results, in the absence of significant disagreement from the Standard Model expectations, limits are placed on various models in both strong and weak sparticle production as well as on models with long-lived sparticles.
SUSY strong production (leptonic) with ATLAS
Saito, Tomoyuki; The ATLAS collaboration
2017-01-01
Supersymmetry is one of the most motivated scenarios for physics beyond the Standard Model. This article summarizes recent ATLAS results on searches for supersymmetry in proton-proton collisions at a centre-of-mass energy of 13 TeV at LHC, which target supersymmetric particles produced by strong interaction in events with leptonic fi nal states. No signi ficant excess above the Standard Model expectation is observed and exclusion limits have been set on squark and gluino masses in various scenarios.
Fuzzy Field Theory as a Random Matrix Model
Tekel, Juraj
This dissertation considers the theory of scalar fields on fuzzy spaces from the point of view of random matrices. First we define random matrix ensembles, which are natural description of such theory. These ensembles are new and the novel feature is a presence of kinetic term in the probability measure, which couples the random matrix to a set of external matrices and thus breaks the original symmetry. Considering the case of a free field ensemble, which is generalization of a Gaussian matrix ensemble, we develop a technique to compute expectation values of the observables of the theory based on explicit Wick contractions and we write down recursion rules for these. We show that the eigenvalue distribution of the random matrix follows the Wigner semicircle distribution with a rescaled radius. We also compute distributions of the matrix Laplacian of the random matrix given by the new term and demonstrate that the eigenvalues of these two matrices are correlated. We demonstrate the robustness of the method by computing expectation values and distributions for more complicated observables. We then consider the ensemble corresponding to an interacting field theory, with a quartic interaction. We use the same method to compute the distribution of the eigenvalues and show that the presence of the kinetic terms rescales the distribution given by the original theory, which is a polynomially deformed Wigner semicircle. We compute the eigenvalue distribution of the matrix Laplacian and the joint distribution up to second order in the correlation and we show that the correlation between the two changes from the free field case. Finally, as an application of these results, we compute the phase diagram of the fuzzy scalar field theory, we find multiscaling which stabilizes this diagram in the limit of large matrices and compare it with the results obtained numerically and by considering the kinetic part as a perturbation.
Universality and Non-Perturbative Definitions of 2D Quantum Gravity from Matrix Models
Miramontes, J L; Guillen, Joaquin Sanchez
1992-01-01
The universality of the non-perturbative definition of Hermitian one-matrix models following the quantum, stochastic, or $d=1$-like stabilization is discussed in comparison with other procedures. We also present another alternative definition, which illustrates the need of new physical input for $d=0$ matrix models to make contact with 2D quantum gravity at the non-perturbative level.
Neutron diffraction measurements and modeling of residual strains in metal matrix composites
Saigal, A.; Leisk, G. G.; Hubbard, C. R.; Misture, S. T.; Wang, X. L.
1996-01-01
Neutron diffraction measurements at room temperature are used to characterize the residual strains in tungsten fiber-reinforced copper matrix, tungsten fiber-reinforced Kanthal matrix, and diamond particulate-reinforced copper matrix composites. Results of finite element modeling are compared with the neutron diffraction data. In tungsten/Kanthal composites, the fibers are in compression, the matrix is in tension, and the thermal residual strains are a strong function of the volume fraction of fibers. In copper matrix composites, the matrix is in tension and the stresses are independent of the volume fraction of tungsten fibers or diamond particles and the assumed stress free temperature because of the low yield strength of the matrix phase.
Extracellular matrix alterations in the ketamine model of schizophrenia.
Matuszko, Gabriela; Curreli, Sebastiano; Kaushik, Rahul; Becker, Axel; Dityatev, Alexander
2017-05-14
The neural extracellular matrix (ECM) plays an important role in regulation of perisomatic GABAergic inhibition and synaptic plasticity in the hippocampus and cortex. Decreased labeling of perineuronal nets, a form of ECM predominantly associated with parvalbumin-expressing interneurons in the brain, has been observed in post-mortem studies of schizophrenia patients, specifically, in brain areas such as prefrontal cortex, entorhinal cortex, and amygdala. Moreover, glial ECM in the form of dandelion clock-like structures was reported to be altered in schizophrenia patients. Here, we verified whether similar abnormalities in neural ECM can be reproduced in a rat model of schizophrenia, in which animals received sub-chronic administration of ketamine to reproduce the aspects of disease related to disrupted signaling through N-methyl-D-aspartate receptors. Our study focused on two schizophrenia-related brain areas, namely the medial prefrontal cortex (mPFC) and hippocampus. Semi-quantitative immunohistochemistry was performed to evaluate investigate ECM expression using Wisteria floribunda agglutinin (WFA) and CS56 antibody, both labeling distinct chondroitin sulfate epitopes enriched in perineuronal nets and glial ECM, respectively. Our analysis revealed that ketamine-treated rats exhibit reduced number of WFA-labeled perineuronal nets, and a decreased intensity of parvalbumin fluorescence in mPFC interneurons somata. Moreover, we found an increased expression of CS56 immunoreactive form of ECM. Importantly, the loss of perineuronal nets was revealed in the mPFC, and was not detected in the hippocampus, suggesting regional specificity of ECM alterations. These data open an avenue for further investigations of functional importance of ECM abnormalities in schizophrenia as well as for search of treatments for their compensation. Copyright © 2017 IBRO. Published by Elsevier Ltd. All rights reserved.
SUSY Discovery at the LHC: Extending Reach with Modern Analysis Methods
Dharmaratna, W G D; Johnson, K F; McDonald, J; Prosper, H B
2006-01-01
We investigate the potential for discovery of supersymmetric matter in the context of the minimal supergravity model (mSUGRA), in the focus point region, by the CMS detector at the LHC. We show that use of a Bayesian neural network discriminant would allow the extraction of a significant SUSY signal, if present, in the presence of large QCD, $t\\bar{t}$, W+jets and Z+jets backgrounds, with as little as one fb$^{-1}$ of integrated luminosity. It is possible that not all of the CMS detector will be fully operational at startup. Consequently, if there are early discoveries to be had only data from those parts of the detector that are functional at, or shortly after, startup will be available. In this paper, we investigate the potential for an early discovery using calorimetric data only, assuming such data will be available at startup.
Experimental results on SUSY searches with top
Eifert, Till
2014-01-01
Searches for supersymmetric partner particles of the top and bottom quarks at the Large Hadron Collider are reviewed. The focus is on the status of searches for a relatively light partner of the top quark performed by the CMS and ATLAS Collaborations. No excess beyond Standard Model expectations is observed and exclusion limits are set on the masses of supersymmetric particles.
Searches for SUSY and Exotics at HERA
Haller, J; Abramowicz, H; Adamczyk, L; Adamus, M; Adler, V; Aghuzumtsyan, G; Antonioli, P; Antonov, A; Arneodo, M; Bailey, D S; Bamberger, A; Barakbaev, A N; Barbagli, G; Barbi, M; Bari, G; Barreiro, F; Bartsch, D; Basile, M; Bauerdick, L A T; Behrens, U; Bell, M; Bellagamba, L; Benen, A; Bertolin, A; Bhadra, S; Bloch, I; Bodmann, B; Bold, T; Boos, E G; Borras, K; Boscherini, D; Brock, I; Brook, N H; Brugnera, R; Brümmer, N; Bruni, A; Bruni, G; Bussey, P J; Butterworth, J M; Bylsma, B; Caldwell, A; Capua, M; Cara Romeo, G; Carli, T; Carlin, R; Catterall, C D; Chekanov, S; Chiochia, V; Chwastowski, J; Ciborowski, J; Ciesielski, R; Cifarelli, Luisa; Cindolo, F; Cloth, P; Cole, J E; Collins-Tooth, C; Contin, A; Cooper-Sarkar, A M; Coppola, N; Cormack, C; Corradi, M; Corriveau, F; Cottrell, A; D'Agostini, Giulio; Dal Corso, F; Danilov, P; Dannheim, D; De Pasquale, S; Dementiev, R K; Derrick, M; Deshpande, Abhay A; Devenish, R C E; Dhawan, S; Dolgoshein, B A; Doyle, A T; Drews, G; Durkin, L S; Dusini, S; Eisenberg, Y; Ermolov, P F; Eskreys, Andrzej; Ferrando, J; Ferrero, M I; Figiel, J; Filges, D; Foster, B; Foudas, C; Fourletov, S; Fourletova, J; Fricke, U; Fusayasu, T; Gabareen, A; Gallo, E; Garfagnini, A; Geiser, A; Genta, C; Gialas, I; Giusti, P; Gladilin, L K; Gladkov, D; Glasman, C; Gliga, S; Goers, S; Golubkov, Yu A; Goncalo, R; González, O; Göttlicher, P; Grabowska-Bold, I; Grijpink, S; Grzelak, G; Gutsche, O; Gwenlan, C; Haas, T; Hain, W; Hall-Wilton, R; Hamatsu, R; Hamilton, J; Hanlon, S; Hart, J C; Hartmann, H; Hartner, G; Hartner, G F; Heaphy, E A; Heath, G P; Heath, H F; Helbich, M; Heusch, C A; Hilger, E; Hillert, S; Hirose, T; Hochman, D; Holm, U; Iacobucci, G; Iga, Y; Inuzuka, M; Irrgang, P; Jakob, H P; Jones, T W; Kagawa, S; Kahle, B; Kaji, H; Kananov, S; Kappes, A; Kataoka, Y; Yamazaki, M; Katkov, I I; Katz, U F; Kcira, D; Khein, L A; Kim, J Y; Kim, Y K; Kind, O; Kisielewska, D; Kitamura, S; Klimek, K; Koffeman, E; Kohno, T; Kooijman, P; Koop, T; Korzhav, I A; Kotanski, A; Kötz, U; Kowal, A M; Kowal, M; Kowalski, H; Kowalski, T; Krakauer, D; Kramberger, G; Kreisel, A; Krumnack, N; Kuze, M; Kuzmin, V A; Labarga, L; Labes, H; Lainesse, J; Lammers, S; Lee, J H; Lee, S W; Lelas, D; Levchenko, B B; Levman, G M; Levy, A; Li, L; Lightwood, M S; Lim, H; Lim, I T; Limentani, S; Ling, T Y; Liu, X; Löhr, B; Lohrmann, E; Loizides, J H; Long, K R; Longhin, A; Lukina, O Yu; Lupi, A; Luzniak, P; Maddox, E; Magill, S; Mankel, R; Margotti, A; Marini, G; Martin, J F; Mastroberardino, A; Matsuzawa, K; Mattingly, M C K; McCubbin, N A; Mellado, B; Melzer-Pellmann, I A; Menary, S R; Metlica, F; Meyer, U; Milite, M; Mirea, A; Monaco, V; Montanari, A; Moritz, M; Musgrave, B; Nagano, K; Nania, R; Nguyen, C N; Nigro, A; Ning, Y; Nishimura, T; Notz, D; Nowak, R J; Oh, B Y; Olkiewicz, K; Pac, M Y; Padhi, S; Paganis, S; Palmonari, F; Parenti, A; Park, I H; Patel, S; Paul, E; Pavel, N; Pawlak, J M; Pelfer, P G; Pellegrino, A; Pesci, A; Petrucci, M C; Piotrzkowski, K; Plucinsky, P P; Pokrovskiy, N S; Polini, A; Posocco, M; Proskuryakov, A S; Przybycien, M B; Rautenberg, J; Raval, A; Reeder, D D; Ren, Z; Renner, R; Repond, J; Riveline, U; Karshon, M; Robins, S; Rodrigues, E; Rosin, M; Rurua, L; Ruspa, M; Sacchi, R; Salehi, H; Sartorelli, G; Savin, A A; Saxon, D H; Schagen, S; Schioppa, M; Schlenstedt, S; Schmidke, W B; Schneekloth, U; Sciulli, F; Scott, J; Selonke, F; Shcheglova, L M; Skillicorn, I O; Slominski, W; Smith, W H; Soares, M; Solano, A; Son, D; Sosnovtsev, V V; Stairs, D G; Stanco, L; Standage, J; Stifutkin, A; Stoesslein, U; Stonjek, S; Stopa, P; Straub, P B; Suchkov, S; Susinno, G; Suszycki, L; Sutton, M R; Sztuk, J; Szuba, D; Szuba, J; Tandler, J; Tapper, A D; Tapper, R J; Tassi, E; Tawara, T; Terron, J; Tiecke, H G; Tokushuku, K; Tsurugai, T; Turcato, M; Tymieniecka, T; Ukleja, A; Ukleja, J; Vázquez, M; Velthuis, J J; Vlasov, N N; Voss, K C; Walczak, R; Walsh, R; Wang, M; Weber, A; Wessoleck, H; West, B J; Whitmore, J J; Wick, K; Wiggers, L; Wills, H H; Wing, M; Wolf, G; Yamada, S; Yamashita, T; Yoshida, R; Youngman, C; Zawiejski, L; Zeuner, W; Zhautykov, B O; Zichichi, A; Ziegler, A; Zotkin, S A; De Wolf, E; Del Peso, J; Haller, Johannes
2004-01-01
The HERA collaborations, H1 and ZEUS, have searched for physics beyond the Standard Model in ep collisions at centre-of-mass energies of up to 319 GeV. In this article the experimental results coming from the HERA I phase are summarised and the constraints on theories of new physics including Contact Interactions, Large Extra Dimensions, Leptoquarks, FCNC and various scenarios in R-parity violating supersymmetry are discussed. In addition the first results on searches for new physics coming from the upgraded HERA II collider are presented.
Jacobi photonic lattices and their SUSY partners.
Zúñiga-Segundo, A; Rodríguez-Lara, B M; Fernández C, David J; Moya-Cessa, H M
2014-01-13
We present a classical analog of quantum optical deformed oscillators in arrays of waveguides. The normal modes of these one-dimensional photonic crystals are given in terms of Jacobi polynomials. We show that it is possible to attack the problem via factorization by exploiting the corresponding quantum optical model. This allows us to provide an unbroken supersymmetric partner of the proposed Jacobi lattices. Thanks to the underlying SU(1, 1) group symmetry of the lattices, we present the analytic propagators and impulse functions for these one-dimensional photonic crystals.
Matrix Models – An Approach to Understand Complex Systems
Indian Academy of Sciences (India)
Matrices with random matrix elements appear to have applications in physics, mathematics, bi- ology, telecommunications, etc. In fact, experi- mental data of many complex systems, such as the spacing distribution of energy level spectra of heavy nuclei, and the distribution of the non- real zeros of the Riemann zeta function ...
Matrix models with Penner interaction inspired by interacting ...
Indian Academy of Sciences (India)
2015-01-29
Jan 29, 2015 ... An additional dependence of the structure combinatorics factor on (related to the size of the matrix and the interaction strength) is obtained. This factor has a strong effect on the structure combinatorics in the low regime. Databases are scanned for real ribonucleic acid (RNA) structures and pairing ...
Physical characterization and kinetic modelling of matrix tablets of ...
African Journals Online (AJOL)
Determination of content uniformity of matrix tablets. Tablets were powdered in a mortar. Powder containing KT equivalent to 40 mg were taken into a 100 mL volumetric flask and diluted with 50. mL water. The suspension was kept in an ultrasonic bath for 5 min. The suspension was filtered through a S & S5893 blue ribbon ...
(Pseudogoldstinos, SUSY fluids, Dirac gravitino and gauginos
Directory of Open Access Journals (Sweden)
Benakli Karim
2014-04-01
Full Text Available We review the emergence and fate of goldstinos in different frameworks. First, we consider a super-Higgs mechanism when supersymmetry breaking is induced by neither an F-term nor a D-term but related to a more general stress energy-momentum tensor. This allows us to build a novel Lagrangian that describes the propagation of a spin-3/2 state in a fluid. Then we briefly review the ubiquitous pseudo-goldstinos when breaking supersymmetry in an extra dimension. We remind that the fermion (gravitino or gaugino soft masses can be tuned to be of Dirac-type. Finally, we briefly connect the latter to the study of models with Dirac-type gaugino masses and stress the advantage of having both an F and a D-term sizable contributions for the hierarchies of soft-terms as well as for minimizing R-symmetry breaking.
Constructing service-oriented architecture adoption maturity matrix using Kano model
Hamzah, Mohd Hamdi Irwan; Baharom, Fauziah; Mohd, Haslina
2017-10-01
Commonly, organizations adopted Service-Oriented Architecture (SOA) because it can provide a flexible reconfiguration and can reduce the development time and cost. In order to guide the SOA adoption, previous industry and academia have constructed SOA maturity model. However, there is a limited number of works on how to construct the matrix in the previous SOA maturity model. Therefore, this study is going to provide a method that can be used in order to construct the matrix in the SOA maturity model. This study adapts Kano Model to construct the cross evaluation matrix focused on SOA adoption IT and business benefits. This study found that Kano Model can provide a suitable and appropriate method for constructing the cross evaluation matrix in SOA maturity model. Kano model also can be used to plot, organize and better represent the evaluation dimension for evaluating the SOA adoption.
Unified continuum damage model for matrix cracking in composite rotor blades
Energy Technology Data Exchange (ETDEWEB)
Pollayi, Hemaraju; Harursampath, Dineshkumar [Nonlinear Multifunctional Composites - Analysis and Design Lab (NMCAD Lab) Department of Aerospace Engineering Indian Institute of Science Bangalore - 560012, Karnataka (India)
2015-03-10
This paper deals with modeling of the first damage mode, matrix micro-cracking, in helicopter rotor/wind turbine blades and how this effects the overall cross-sectional stiffness. The helicopter/wind turbine rotor system operates in a highly dynamic and unsteady environment leading to severe vibratory loads present in the system. Repeated exposure to this loading condition can induce damage in the composite rotor blades. These rotor/turbine blades are generally made of fiber-reinforced laminated composites and exhibit various competing modes of damage such as matrix micro-cracking, delamination, and fiber breakage. There is a need to study the behavior of the composite rotor system under various key damage modes in composite materials for developing Structural Health Monitoring (SHM) system. Each blade is modeled as a beam based on geometrically non-linear 3-D elasticity theory. Each blade thus splits into 2-D analyzes of cross-sections and non-linear 1-D analyzes along the beam reference curves. Two different tools are used here for complete 3-D analysis: VABS for 2-D cross-sectional analysis and GEBT for 1-D beam analysis. The physically-based failure models for matrix in compression and tension loading are used in the present work. Matrix cracking is detected using two failure criterion: Matrix Failure in Compression and Matrix Failure in Tension which are based on the recovered field. A strain variable is set which drives the damage variable for matrix cracking and this damage variable is used to estimate the reduced cross-sectional stiffness. The matrix micro-cracking is performed in two different approaches: (i) Element-wise, and (ii) Node-wise. The procedure presented in this paper is implemented in VABS as matrix micro-cracking modeling module. Three examples are presented to investigate the matrix failure model which illustrate the effect of matrix cracking on cross-sectional stiffness by varying the applied cyclic load.
Energy Technology Data Exchange (ETDEWEB)
Arganda, E.; Penaranda, S. [Universidad de Zaragoza, Departamento de Fisica Teorica, Facultad de Ciencias, Zaragoza (Spain); Guasch, J. [Universitat de Barcelona, Departament de Fisica Fonamental, Barcelona, Catalonia (Spain); Universitat de Barcelona, Institut de Ciencies del Cosmos (ICC), Barcelona, Catalonia (Spain); Hollik, W. [Max-Planck-Institut fuer Physik, Muenchen (Germany)
2016-05-15
It is still an open question whether the new scalar particle discovered at the LHC with a mass of 125 GeV is the SM Higgs boson or belongs to models of new physics with an extended Higgs sector, as the MSSM or 2HDM. The ratio of branching fractions R = BR(H → b anti b)/BR(H → τ{sup +}τ{sup -}) of Higgs-boson decays is a powerful tool in distinguishing the MSSM Higgs sector from the SM or non-supersymmetric 2HDM. This ratio receives large renormalization-scheme independent radiative corrections in supersymmetric models at large tan β, which are insensitive to the SUSY mass scale and absent in the SM or 2HDM. Making use of the current LHC data and the upcoming new results on Higgs couplings to be reported by ATLAS and CMS collaborations and in a future linear collider, we develop a detailed and updated study of this ratio R which improves previous analyses and sets the level of accuracy needed to discriminate between models. (orig.)
Directory of Open Access Journals (Sweden)
Fischer Carsten
2010-07-01
Full Text Available Abstract Background Current approaches in bone regeneration combine osteoconductive scaffolds with bioactive cytokines like BMP or VEGF. The idea of our in-vitro trial was to apply VEGF165 in gradient concentrations to an equine collagen carrier and to study pharmacological and morphological characteristics of the complex in a circulation model. Methods Release kinetics of VEGF165 complexed in different quantities in a collagen matrix were determined in a circulation model by quantifying protein concentration with ELISA over a period of 5 days. The structural changes of the collagen matrix were assessed with light microscopy, native scanning electron microscopy (SEM as well as with immuno-gold-labelling technique in scanning and transmission electron microscopy (TEM. Results We established a biological half-life for VEGF165 of 90 minutes. In a half-logarithmic presentation the VEGF165 release showed a linear declining gradient; the release kinetics were not depending on VEGF165 concentrations. After 12 hours VEGF release reached a plateau, after 48 hours VEGF165 was no longer detectable in the complexes charged with lower doses, but still measurable in the 80 μg sample. At the beginning of the study a smear layer was visible on the surface of the complex. After the wash out of the protein in the first days the natural structure of the collagen appeared and did not change over the test period. Conclusions By defining the pharmacological and morphological profile of a cytokine collagen complex in a circulation model our data paves the way for further in-vivo studies where additional biological side effects will have to be considered. VEGF165 linked to collagen fibrils shows its improved stability in direct electron microscopic imaging as well as in prolonged release from the matrix. Our in-vitro trial substantiates the position of cytokine collagen complexes as innovative and effective treatment tools in regenerative medicine and and may initiate
Neutrinoless double beta nuclear matrix elements around mass 80 in the nuclear shell-model
Directory of Open Access Journals (Sweden)
Yoshinaga N.
2015-01-01
Full Text Available The observation of the neutrinoless double-beta decay can determine whether the neutrino is a Majorana particle or not. For theoretical nuclear physics it is particularly important to estimate three types of matrix elements, namely Fermi (F, Gamow-Teller (GT, and tensor (T matrix elements. In this paper, we carry out shell-model calculations and also pair-truncated shell-model calculations to check the model dependence in the case of mass A=82 nuclei.
Muon g - 2 through a flavor structure on soft SUSY terms
Energy Technology Data Exchange (ETDEWEB)
Flores-Baez, F.V. [Universidad Autonoma de Nuevo Leon, UANL Ciudad Universitaria, FCFM, San Nicolas de los Garza, Nuevo Leon (Mexico); Gomez Bock, M. [Universidad de las Americas Puebla, UDLAP, Ex-Hacienda Sta. Catarina Martir, DAFM, Cholula, Puebla (Mexico); Mondragon, M. [Universidad Nacional Autonoma de Mexico, Instituto de Fisica, Apdo. Postal 20-364, Mexico, D.F. (Mexico)
2016-10-15
In this work we analyze the possibility to explain the muon anomalous magnetic moment discrepancy within theory and experiment through lepton-flavor violation processes. We propose a flavor extended MSSM by considering a hierarchical family structure for the trilinear scalar soft-supersymmetric terms of the Lagrangian, present at the SUSY breaking scale. We obtain analytical results for the rotation mass matrix, with the consequence of having non-universal slepton masses and the possibility of leptonic flavor mixing. The one-loop supersymmetric contributions to the leptonic flavor violating process τ → μγ are calculated in the physical basis, instead of using the well-known mass-insertion method. The flavor violating processes BR(l{sub i} → l{sub j}γ) are also obtained, in particular τ → μγ is well within the experimental bounds. We present the regions in parameter space where the muon g - 2 problem is either entirely solved or partially reduced through the contribution of these flavor violating processes. (orig.)
Population dynamics of species-rich ecosystems: the mixture of matrix population models approach
DEFF Research Database (Denmark)
Mortier, Frédéric; Rossi, Vivien; Guillot, Gilles
2013-01-01
Matrix population models are widely used to predict population dynamics, but when applied to species-rich ecosystems with many rare species, the small population sample sizes hinder a good fit of species-specific models. This issue can be overcome by assigning species to groups to increase the size...... species with similar population dynamics....... of the calibration data sets. However, the species classification is often disconnected from the matrix modelling and from the estimation of matrix parameters, thus bringing species groups that may not be optimal with respect to the predicted community dynamics. We proposed here a method that jointly classified...
Bienvenu, François; Akçay, Erol; Legendre, Stéphane; McCandlish, David M
2017-06-01
Matrix projection models are a central tool in many areas of population biology. In most applications, one starts from the projection matrix to quantify the asymptotic growth rate of the population (the dominant eigenvalue), the stable stage distribution, and the reproductive values (the dominant right and left eigenvectors, respectively). Any primitive projection matrix also has an associated ergodic Markov chain that contains information about the genealogy of the population. In this paper, we show that these facts can be used to specify any matrix population model as a triple consisting of the ergodic Markov matrix, the dominant eigenvalue and one of the corresponding eigenvectors. This decomposition of the projection matrix separates properties associated with lineages from those associated with individuals. It also clarifies the relationships between many quantities commonly used to describe such models, including the relationship between eigenvalue sensitivities and elasticities. We illustrate the utility of such a decomposition by introducing a new method for aggregating classes in a matrix population model to produce a simpler model with a smaller number of classes. Unlike the standard method, our method has the advantage of preserving reproductive values and elasticities. It also has conceptually satisfying properties such as commuting with changes of units. Copyright © 2017 Elsevier Inc. All rights reserved.
Searches for SUSY with other than jets + X + MET signature with the ATLAS detector
Kopeliansky, R; The ATLAS collaboration
2013-01-01
Searches for SUSY with other than jets + X + MET: EW production: Colored sparticles are heavy, the production is suppressed Gauginos & Sleptons assumed to be light enough to be produced Several scenarios including mainly
Two-loop SUSY QCD correction to the gluino pole mass
Yamada, Youichi
2006-01-01
We calculate the pole mass of the gluino as a function of the running parameters in the lagrangian, to O(alpha_s^2) in SUSY QCD. The correction shifts the pole mass from the running mass by typically 1-2 %. This shift can be larger than the expected accuracy of the mass determination at future colliders, and should be taken into account for precision studies of the SUSY breaking parameters. The effects of other corrections are breifly commented.
A Random Matrix Approach for Quantifying Model-Form Uncertainties in Turbulence Modeling
Xiao, Heng; Ghanem, Roger G
2016-01-01
With the ever-increasing use of Reynolds-Averaged Navier--Stokes (RANS) simulations in mission-critical applications, the quantification of model-form uncertainty in RANS models has attracted attention in the turbulence modeling community. Recently, a physics-based, nonparametric approach for quantifying model-form uncertainty in RANS simulations has been proposed, where Reynolds stresses are projected to physically meaningful dimensions and perturbations are introduced only in the physically realizable limits. However, a challenge associated with this approach is to assess the amount of information introduced in the prior distribution and to avoid imposing unwarranted constraints. In this work we propose a random matrix approach for quantifying model-form uncertainties in RANS simulations with the realizability of the Reynolds stress guaranteed. Furthermore, the maximum entropy principle is used to identify the probability distribution that satisfies the constraints from available information but without int...
2014-11-16
Pandurangan, B., Yen, C-.F., Cheeseman, B. A., Wang, Y., Miao, Y. & Zheng, J. Q. “ Fiber -level Modeling of Dynamic Strength of Kevlar ® KM2 Ballistic...A. “Multi-Length Scale Enriched Continuum-Level Material Model for Kevlar ®- Fiber Reinforced Polymer- Matrix Composites” Journal of Materials Engineering and Performance 22 (2013): 681-695. ... Fiber Reinforced Polymer Matrix Composites Used in Ballistic Protection Applications Clemson University Clemson SC 242 Army Research Laboratory
Higgs pair production with SUSY QCD correction: revisited under current experimental constraints
Energy Technology Data Exchange (ETDEWEB)
Han, Chengcheng [State Key Laboratory of Theoretical Physics, Institute of Theoretical Physics, Academia Sinica,Beijing 100190 (China); Ji, Xuanting [State Key Laboratory of Theoretical Physics, Institute of Theoretical Physics, Academia Sinica,Beijing 100190 (China); Institute of Theoretical Physics, College of Applied Science, Beijing University of Technology,Beijing 100124 (China); Wu, Lei [ARC Centre of Excellence for Particle Physics at the Terascale, School of Physics,University of Sydney,Sydney, NSW 2006 (Australia); Wu, Peiwen; Yang, Jin Min [State Key Laboratory of Theoretical Physics, Institute of Theoretical Physics, Academia Sinica,Beijing 100190 (China)
2014-04-01
We consider the current experimental constraints on the parameter space of the MSSM and NMSSM. Then in the allowed parameter space we examine the Higgs pair production at the 14 TeV LHC via bb-macron→hh (h is the 125 GeV SM-like Higg boson) with one-loop SUSY QCD correction and compare it with the production via gg→hh. We obtain the following observations: (i) For the MSSM the production rate of bb-macron→hh can reach 50 fb and thus can be competitive with gg→hh, while for the NMSSM bb-macron→hh has a much smaller rate than gg→hh due to the suppression of the hbb-macron coupling; (ii) The SUSY-QCD correction to bb-macron→hh is sizable, which can reach 45% for the MSSM and 15% for the NMSSM within the 1σ region of the Higgs data; (iii) In the heavy SUSY limit (all soft mass parameters become heavy), the SUSY effects decouple rather slowly from the Higgs pair production (especially the gg→hh process), which, for M{sub SUSY}=5 TeV and m{sub A}<1 TeV, can enhance the production rate by a factor of 1.5 and 1.3 for the MSSM and NMSSM, respectively. So, the Higgs pair production may be helpful for unraveling the effects of heavy SUSY.
Modelling of polypropylene fibre-matrix composites using finite element analysis
Directory of Open Access Journals (Sweden)
2009-01-01
Full Text Available Polypropylene (PP fibre-matrix composites previously prepared and studied experimentally were modelled using finite element analysis (FEA in this work. FEA confirmed that fibre content and composition controlled stress distribution in all-PP composites. The stress concentration at the fibre-matrix interface became greater with less fibre content. Variations in fibre composition were more significant in higher stress regions of the composites. When fibre modulus increased, the stress concentration at the fibres decreased and the shear stress at the fibre-matrix interface became more intense. The ratio between matrix modulus and fibre modulus was important, as was the interfacial stress in reducing premature interfacial failure and increasing mechanical properties. The model demonstrated that with low fibre concentration, there were insufficient fibres to distribute the applied stress. Under these conditions the matrix yielded when the applied stress reached the matrix yield stress, resulting in increased fibre axial stress. When the fibre content was high, there was matrix depletion and stress transfer was inefficient. The predictions of the FEA model were consistent with experimental and published data.
Transient Analysis of Hysteresis Queueing Model Using Matrix Geometric Method
Directory of Open Access Journals (Sweden)
Wajiha Shah
2011-10-01
Full Text Available Various analytical methods have been proposed for the transient analysis of a queueing system in the scalar domain. In this paper, a vector domain based transient analysis is proposed for the hysteresis queueing system with internal thresholds for the efficient and numerically stable analysis. In this system arrival rate of customer is controlled through the internal thresholds and the system is analyzed as a quasi-birth and death process through matrix geometric method with the combination of vector form Runge-Kutta numerical procedure which utilizes the special matrices. An arrival and service process of the system follows a Markovian distribution. We analyze the mean number of customers in the system when the system is in transient state against varying time for a Markovian distribution. The results show that the effect of oscillation/hysteresis depends on the difference between the two internal threshold values.
Realizing three generations of the Standard Model fermions in the type IIB matrix model
Aoki, Hajime; Nishimura, Jun; Tsuchiya, Asato
2014-05-01
We discuss how the Standard Model particles appear from the type IIB matrix model, which is considered to be a nonperturbative formulation of superstring theory. In particular, we are concerned with a constructive definition of the theory, in which we start with finite- N matrices and take the large- N limit afterwards. In that case, it was pointed out recently that realizing chiral fermions in the model is more difficult than it had been thought from formal arguments at N = ∞ and that introduction of a matrix version of the warp factor is necessary. Based on this new insight, we show that two generations of the Standard Model fermions can be realized by considering a rather generic configuration of fuzzy S2 and fuzzy S2 × S2 in the extra dimensions. We also show that three generations can be obtained by squashing one of the S2's that appear in the configuration. Chiral fermions appear at the intersections of the fuzzy manifolds with nontrivial Yukawa couplings to the Higgs field, which can be calculated from the overlap of their wave functions.
A new approach to a global fit of the CKM matrix
Energy Technology Data Exchange (ETDEWEB)
Hoecker, A.; Lacker, H.; Laplace, S. [Laboratoire de l' Accelerateur Lineaire, 91 - Orsay (France); Le Diberder, F. [Laboratoire de Physique Nucleaire et des Hautes Energies, 75 - Paris (France)
2001-05-01
We report on a new approach to a global CKM matrix analysis taking into account most recent experimental and theoretical results. The statistical framework (Rfit) developed in this paper advocates frequentist statistics. Other approaches, such as Bayesian statistics or the 95% CL scan method are also discussed. We emphasize the distinction of a model testing and a model dependent, metrological phase in which the various parameters of the theory are estimated. Measurements and theoretical parameters entering the global fit are thoroughly discussed, in particular with respect to their theoretical uncertainties. Graphical results for confidence levels are drawn in various one and two-dimensional parameter spaces. Numerical results are provided for all relevant CKM parameterizations, the CKM elements and theoretical input parameters. Predictions for branching ratios of rare K and B meson decays are obtained. A simple, predictive SUSY extension of the Standard Model is discussed. (authors)
A matrix approach to the statistics of longevity in heterogeneous frailty models
Directory of Open Access Journals (Sweden)
Hal Caswell
2014-09-01
Full Text Available Background: The gamma-Gompertz model is a fixed frailty model in which baseline mortality increasesexponentially with age, frailty has a proportional effect on mortality, and frailty at birth follows a gamma distribution. Mortality selects against the more frail, so the marginal mortality rate decelerates, eventually reaching an asymptote. The gamma-Gompertz is one of a wider class of frailty models, characterized by the choice of baseline mortality, effects of frailty, distributions of frailty, and assumptions about the dynamics of frailty. Objective: To develop a matrix model to compute all the statistical properties of longevity from thegamma-Gompertz and related models. Methods: I use the vec-permutation matrix formulation to develop a model in which individuals are jointly classified by age and frailty. The matrix is used to project the age and frailty dynamicsof a cohort and the fundamental matrix is used to obtain the statistics of longevity. Results: The model permits calculation of the mean, variance, coefficient of variation, skewness and all moments of longevity, the marginal mortality and survivorship functions, the dynamics of the frailty distribution, and other quantities. The matrix formulation extends naturally to other frailty models. I apply the analysis to the gamma-Gompertz model (for humans and laboratory animals, the gamma-Makeham model, and the gamma-Siler model, and to a hypothetical dynamic frailty model characterized by diffusion of frailty with reflecting boundaries.The matrix model permits partitioning the variance in longevity into components due to heterogeneity and to individual stochasticity. In several published human data sets, heterogeneity accounts for less than 10Š of the variance in longevity. In laboratory populations of five invertebrate animal species, heterogeneity accounts for 46Š to 83Š ofthe total variance in longevity.
Modeling social influence through network autocorrelation : constructing the weight matrix
Leenders, Roger Th. A. J.
Many physical and social phenomena are embedded within networks of interdependencies, the so-called 'context' of these phenomena. In network analysis, this type of process is typically modeled as a network autocorrelation model. Parameter estimates and inferences based on autocorrelation models,
Estimation and Q-Matrix Validation for Diagnostic Classification Models
Feng, Yuling
2013-01-01
Diagnostic classification models (DCMs) are structured latent class models widely discussed in the field of psychometrics. They model subjects' underlying attribute patterns and classify subjects into unobservable groups based on their mastery of attributes required to answer the items correctly. The effective implementation of DCMs depends…
Energy Technology Data Exchange (ETDEWEB)
Harz, Julia [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Herrmann, Bjoern [Laboratoire d' Annecy de Physique Theorique, Annecy-le-Vieux (France); Klasen, Michael; Meinecke, Moritz; Steppeler, Patrick [Institute of Theoretical Physics Muenster (Germany); Kovarik, Karol [Karlsruher Institut fuer Technologie (KIT), Karlsruhe (Germany); Le Boulc' h, Quentin [Laboratoire de Physique Subatomique et de Cosmologie, Grenoble (France)
2013-07-01
A powerful method to constrain the parameter space of theories beyond the Standard Model is to compare the predicted dark matter relic density with cosmological precision measurements, in particular with WMAP- and the upcoming Planck-data. On the particle physics side, the main uncertainty on the relic density arises from the (co-)annihilation cross sections of the dark matter particle. After a motivation for including higher order corrections in the prediction of the relic density, the DM rate at NLO-project will be presented, a software package that allows for the computation of the neutralino (co-)annihilation cross sections including SUSY-QCD corrections at the one-loop level and the evaluation of their effect on the relic density using a link to the public codes MicrOMEGAs and DarkSUSY. Recent results of the impact of SUSY-QCD corrections on the neutralino (co-)annihilation cross section as well as further ongoing projects in the context of the DM rate at NLO-project are discussed.
Computation of the Exact Information Matrix of Gaussian Dynamic Regression Time Series Models
Klein, A.A.B.; Melard, G.; Zahaf, T.
1998-01-01
In this paper, the computation of the exact Fisher information matrix of a large class of Gaussian time series models is considered. This class, which is often called the single-input-single-output (SISO) model, includes dynamic regression with autocorrelated errors and the transfer function model,
Energy Technology Data Exchange (ETDEWEB)
Kaminska, Anna [Oxford Univ. (United Kingdom). Centre for Theoretical Physics; Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Ross, Graham G. [Oxford Univ. (United Kingdom). Centre for Theoretical Physics; Schmidt-Hoberg, Kai [European Lab. for Particle Physics (CERN), Geneva (Switzerland)
2013-08-15
For the case of the MSSM and the most general form of the NMSSM (GNMSSM) we determine the reduction in the fine tuning that follows from allowing gaugino masses to be non-degenerate at the unification scale, taking account of the LHC8 bounds on SUSY masses, the Higgs mass bound, gauge coupling unification and the requirement of an acceptable dark matter density. We show that low-fine tuned points fall in the region of gaugino mass ratios predicted by specific unified and string models. For the case of the MSSM the minimum fine tuning is still large, approximately 1:60 allowing for a 3 GeV uncertainty in the Higgs mass (1:500 for the central value), but for the GNMSSM it is below 1:20. We find that the spectrum of SUSY states corresponding to the low-fine tuned points in the GNMSSM is often compressed, weakening the LHC bounds on coloured states. The prospect for testing the remaining low-fine-tuned regions at LHC14 is discussed.
Medina, Anibal D.; Schmidt, Michael A.
2017-08-01
In the Minimal Supersymmetric Standard Model (MSSM) searches for the heaviest CP-even and CP-odd Higgs H, A to tau-lepton pairs severely constrain the parameter region for large values of tan β and light Higgs bosons H, A. We demonstrate how the experimental constraint can be avoided by new decays to light third-generation sfermions, whose left-right couplings to H can be maximised in regions of large trilinear couplings A b , A τ for sbottoms and staus, or large supersymmetric (SUSY) Higgs mass μ for stops. Due to the tan β-enhancement in the production cross-sections via gluon-fusion and in association with bottom-quark pairs for H and A, we find that down-type sfermions, in particular, sbottoms perform a better job in allowing more parameter space than up-type sfermions such as stops, which require much larger values of μ to compensate for tan β. Vacuum stability as well as flavour observables constraints and direct searches for SUSY particles are imposed. We also associate the lightest CP-even Higgs with the observed 125 GeV SM-like Higgs and impose the experimental constraints from the LHC.
Quantized gauge theory on the fuzzy sphere as random matrix model
Energy Technology Data Exchange (ETDEWEB)
Steinacker, Harold E-mail: harold.steinacker@physik.uni-muenchen.de
2004-02-16
U(n) Yang-Mills theory on the fuzzy sphere S{sup 2}{sub N} is quantized using random matrix methods. The gauge theory is formulated as a matrix model for a single Hermitian matrix subject to a constraint, and a potential with two degenerate minima. This allows to reduce the path integral over the gauge fields to an integral over eigenvalues, which can be evaluated for large N. The partition function of U(n) Yang-Mills theory on the classical sphere is recovered in the large N limit, as a sum over instanton contributions. The monopole solutions are found explicitly.
A planar model study of creep in metal matrix composites with misaligned short fibres
DEFF Research Database (Denmark)
Sørensen, N.J.
1993-01-01
The effect of fibre misalignment on the creep behaviour of metal matrix composites is modelled, including hardening behaviour (stage 1), dynamic recovery and steady state creep (stage 2) of the matrix material, using an internal variable constitutive model for the creep behaviour of the metal...... for the composite is markedly reduced by the fibre misalignment and the time needed to reach an approximate steady state is elongated due to the strain induced rotation of the short fibres in the matrix....... matrix. Numerical plane strain results in terms of average properties and detailed local deformation behaviour up to large strains are needed to show effects of fibre misalignment on the development of inelastic strains and the resulting over-all creep resistance of the material. The creep resistance...
Energy Technology Data Exchange (ETDEWEB)
Jakob, A
2004-07-01
In this report a comprehensive overview on the matrix diffusion of solutes in fractured crystalline rocks is presented. Some examples from observations in crystalline bedrock are used to illustrate that matrix diffusion indeed acts on various length scales. Fickian diffusion is discussed in detail followed by some considerations on rock porosity. Due to the fact that the dual-porosity medium model is a very common and versatile method for describing solute transport in fractured porous media, the transport equations and the fundamental assumptions, approximations and simplifications are discussed in detail. There is a variety of geometrical aspects, processes and events which could influence matrix diffusion. The most important of these, such as, e.g., the effect of the flow-wetted fracture surface, channelling and the limited extent of the porous rock for matrix diffusion etc., are addressed. In a further section open issues and unresolved problems related to matrix diffusion are mentioned. Since matrix diffusion is one of the key retarding processes in geosphere transport of dissolved radionuclide species, matrix diffusion was consequently taken into account in past performance assessments of radioactive waste repositories in crystalline host rocks. Some issues regarding matrix diffusion are site-specific while others are independent of the specific situation of a planned repository for radioactive wastes. Eight different performance assessments from Finland, Sweden and Switzerland were considered with the aim of finding out how matrix diffusion was addressed, and whether a consistent picture emerges regarding the varying methodology of the different radioactive waste organisations. In the final section of the report some conclusions are drawn and an outlook is given. An extensive bibliography provides the reader with the key papers and reports related to matrix diffusion. (author)
Tornambe, Peter; The ATLAS collaboration
2017-01-01
Supersymmetry (SUSY) is one of the most studied theories to extend the Standard Model (SM) beyond the electroweak scale. If R-parity is conserved, SUSY particles are produced in pairs and the lightest supersymmetric particle (LSP), which is typically the lightest neutrino $\\tilde{\\chi}_1^0$, is stable. In many models the LSP can be a suitable candidate for dark matter. This poster presents a search for supersymmetric phenomena in final states with two leptons (electrons or muons) of the same electric charge or three leptons, jets and missing transverse energy. While the same-sign or three leptons signature is present in many SUSY scenarios, SM processes leading to such events have very small cross-sections. Therefore, this analysis benefits from a small SM background in the signal regions leading to a good sensitivity especially in SUSY scenarios with compressed mass spectra or in which the R-parity is not conserved. Except from the prompt production of same-sign lepton pairs or three leptons, the main source...
Operational matrix approach for approximate solution of fractional model of Bloch equation
Directory of Open Access Journals (Sweden)
Harendra Singh
2017-04-01
Full Text Available In present paper operational matrix of integration for Laguerre polynomial is used to solve fractional model of Bloch equation in nuclear magnetic resonance (NMR. The operational matrix converts the Bloch equation in a system of linear algebraic equations. Solving system we obtain the approximate solutions for fractional Bloch equation. Results are compared with existing methods and exact solution. Graphs are plotted for different fractional values of time derivatives.
Unitary-matrix models as exactly solvable string theories
Periwal, Vipul; Shevitz, Danny
1990-01-01
Exact differential equations are presently found for the scaling functions of models of unitary matrices which are solved in a double-scaling limit, using orthogonal polynomials on a circle. For the case of the simplest, k = 1 model, the Painleve II equation with constant 0 is obtained; possible nonperturbative phase transitions exist for these models. Equations are presented for k = 2 and 3, and discussed with a view to asymptotic behavior.
Mapping regulatory models for medicinal cannabis: a matrix of options.
Belackova, Vendula; Shanahan, Marian; Ritter, Alison
2017-05-30
Objective The aim of the present study was to develop a framework for assessing regulatory options for medicinal cannabis in Australia.Methods International regulatory regimes for medicinal cannabis were reviewed with a qualitative policy analysis approach and key policy features were synthesised, leading to a conceptual framework that facilitates decision making across multiple dimensions.Results Two central organising dimensions of medicinal cannabis regulation were identified: cannabis supply and patient authorisation (including patient access). A number of the different supply options can be matched with a number of different patient authorisation options, leading to a matrix of possible regulatory regimes.Conclusions The regulatory options, as used internationally, involve different forms of cannabis (synthetic and plant-based pharmaceutical preparations or herbal cannabis) and the varying extent to which patient authorisation policies and procedures are stringently or more loosely defined. The optimal combination of supply and patient authorisation options in any jurisdiction that chooses to make medicinal cannabis accessible will depend on policy goals.What is known about the topic? Internationally, regulation of medicinal cannabis has developed idiosyncratically, depending on formulations that were made available and local context. There has been no attempt to date in the scientific literature to systematically document the variety of regulatory possibilities for medicinal cannabis.What does this paper add? This paper presents a new conceptual schema for considering options for the regulation of medicinal cannabis, across both supply and patient authorisation aspects.What are the implications for practitioners? The design of regulatory systems in Australia, whether for pharmaceutical or herbal products, is a vital issue for policy makers right now as federal and state and territory governments grapple with the complexities of medicinal cannabis regulation
Influence of input matrix representation on topic modelling performance
CSIR Research Space (South Africa)
De Waal, A
2010-11-01
Full Text Available different feature dimension sizes. This is in contrast with existing methods such as perplexity, which depend on the size of the vocabulary modelled and can therefore not be used to compare models which use different input feature sets. We use a stability...
Camera-Model Identification Using Markovian Transition Probability Matrix
Xu, Guanshuo; Gao, Shang; Shi, Yun Qing; Hu, Ruimin; Su, Wei
Detecting the (brands and) models of digital cameras from given digital images has become a popular research topic in the field of digital forensics. As most of images are JPEG compressed before they are output from cameras, we propose to use an effective image statistical model to characterize the difference JPEG 2-D arrays of Y and Cb components from the JPEG images taken by various camera models. Specifically, the transition probability matrices derived from four different directional Markov processes applied to the image difference JPEG 2-D arrays are used to identify statistical difference caused by image formation pipelines inside different camera models. All elements of the transition probability matrices, after a thresholding technique, are directly used as features for classification purpose. Multi-class support vector machines (SVM) are used as the classification tool. The effectiveness of our proposed statistical model is demonstrated by large-scale experimental results.
SUSY-QCD corrections to the (co)annihilation of neutralino dark matter within the MSSM
Energy Technology Data Exchange (ETDEWEB)
Meinecke, Moritz
2015-06-15
Based on experimental observations, it is nowadays assumed that a large component of the matter content in the universe is comprised of so-called cold dark matter. Furthermore, latest measurements of the temperature fluctuations of the cosmic microwave background provided an estimation of the dark matter relic density at a measurement error of one percent (concerning the experimental 1σ-error). The lightest neutralino χ 0{sub 1}, a particle which subsumes under the phenomenologically interesting category of weakly interacting massive particles, is a viable dark matter candidate for many supersymmetric (SUSY) models whose relic density Ω{sub χ} {sub 0{sub 1}} happens to lie quite naturally within the experimentally favored ballpark of dark matter. The high experimental precision can be used to constrain the SUSY parameter space to its cosmologically favored regions and to pin down phenomenologically interesting scenarios. However, to actually benefit from this progress on the experimental side it is also mandatory to minimize the theoretical uncertainties. An important quantity within the calculation of the neutralino relic density is the thermally averaged sum over different annihilation and coannihilation cross sections of the neutralino and further supersymmetric particles. It is now assumed and also partly proven that these cross sections can be subject to large loop corrections which can even shift the associated Ω{sub χ} {sub 0{sub 1}} by a factor larger than the current experimental error. However, most of these corrections are yet unknown. In this thesis, we calculate higher-order corrections for some of the most important (co)annihilation channels both within the framework of the R-parity conserving Minimal Supersymmetric Standard Model (MSSM) and investigate their impact on the final neutralino relic density Ω{sub χ} {sub 0{sub 1}}. More precisely, this work provides the full O(α{sub s}) corrections of supersymmetric quantum chromodynamics (SUSY
Assessment of Matrix coils in a canine model of a large bifurcation aneurysm
Energy Technology Data Exchange (ETDEWEB)
Song, Joon K.; Niimi, Yasunari; Yoshino, Yoshikazu; Khoyama, Shinya; Berenstein, Alejandro [Roosevelt Hospital, Center for Endovascular Surgery, Beth Israel Hyman-Newman Institute for Neurology and Neurosurgery, New York, NY (United States)
2007-03-15
Controversy exists as to whether Matrix coils are an improvement over bare platinum coils in preventing aneurysm recanalization in endosaccularly coiled large aneurysms. We investigated Matrix coils in a dog model of a wide-necked large bifurcation aneurysm. Six experimental aneurysms were created in dogs and these aneurysms were endosaccularly coiled with 100% Matrix coils. Angiographic and histopathological data were analyzed at 2 weeks and at 3 months. Average aneurysm dimensions were length 17.8 mm, width 8.3 mm, and neck 6.2 mm. Aneurysm coil filling ranged 24.1-41.8% by volume. At 14 days, three of six Matrix-treated aneurysms showed coil compaction and aneurysm recanalization. At 3 months, one additional Matrix-treated aneurysm showed delayed coil compaction and aneurysm recanalization. At 3 months, in three harvested aneurysms, the average measured neck neointima was 0.150 {+-} 0.14 mm. However, in two of the three aneurysms harvested at 3 months, aneurysm recanalization had occurred with neointimal tissue not completely covering the aneurysm orifice. Thick connective fibrous intercoil tissue was observed. No immediate or delayed thrombus formation had occurred. Based on limited data in an experimental bifurcation aneurysm in dogs, Matrix coils appear to induce a thicker aneurysm neck neointima tissue and intercoil granulation response but appear prone to coil compaction and aneurysm recanalization. Modifications to the Matrix coil are likely needed to improve angiographic results in large aneurysms. (orig.)
Exact solution of Chern-Simons-matter matrix models with characteristic/orthogonal polynomials
Energy Technology Data Exchange (ETDEWEB)
Tierz, Miguel [Departamento de Matemática, Grupo de Física Matemática,Faculdade de Ciências, Universidade de Lisboa,Campo Grande, Edifício C6, 1749-016 Lisboa (Portugal)
2016-04-27
We solve for finite N the matrix model of supersymmetric U(N) Chern-Simons theory coupled to N{sub f} fundamental and N{sub f} anti-fundamental chiral multiplets of R-charge 1/2 and of mass m, by identifying it with an average of inverse characteristic polynomials in a Stieltjes-Wigert ensemble. This requires the computation of the Cauchy transform of the Stieltjes-Wigert polynomials, which we carry out, finding a relationship with Mordell integrals, and hence with previous analytical results on the matrix model. The semiclassical limit of the model is expressed, for arbitrary N{sub f}, in terms of a single Hermite polynomial. This result also holds for more general matter content, involving matrix models with double-sine functions.
Followee Recommendation in Microblog Using Matrix Factorization Model with Structural Regularization
Directory of Open Access Journals (Sweden)
Yan Yu
2014-01-01
Full Text Available Microblog that provides us a new communication and information sharing platform has been growing exponentially since it emerged just a few years ago. To microblog users, recommending followees who can serve as high quality information sources is a competitive service. To address this problem, in this paper we propose a matrix factorization model with structural regularization to improve the accuracy of followee recommendation in microblog. More specifically, we adapt the matrix factorization model in traditional item recommender systems to followee recommendation in microblog and use structural regularization to exploit structure information of social network to constrain matrix factorization model. The experimental analysis on a real-world dataset shows that our proposed model is promising.
The Topological CP1 Model and the Large-N Matrix Integral
Eguchi, Tohru; Yang, Sung-Kil
We discuss the topological CP1 model which consists of the holomorphic maps from Riemann surfaces onto CP1. We construct a large-N matrix model which reproduces precisely the partition function of the CP1 model at all genera of Riemann surfaces. The action of our matrix model has the form \\begin{array}{c} {\\rm Tr}\\, V (M) = -2\\, {\\rm Tr}\\, M (\\log M -1) +2\\displaystyle\\sum t_{n, P}\\, {\\rm Tr}\\, M^n (\\log M -c_n)\\\\[5pt] \\kern8pt +\\displaystyle\\sum 1/n\\cdot t_{n -1, Q}\\, {\\rm Tr}\\, M^n\\,, \\quad c_n =\\displaystyle\\sum_1^n 1/j\\,, \\end{array} where M is an N × N Hermitian matrix and tn,P(tn,Q), (n = 0, 1, 2, …) are the coupling constants of the nth descendant of the puncture (Kähler) operator.
Polymer Matrix Composites using Fused Deposition Modeling Technology Project
National Aeronautics and Space Administration — Fused deposition modeling (FDM) is an additive manufacturing technology that allows fabrication of complex three-dimensional geometries layer-by-layer. The goal of...
Large N meson masses from a matrix model
Energy Technology Data Exchange (ETDEWEB)
González-Arroyo, Antonio, E-mail: antonio.gonzalez-arroyo@uam.es [Instituto de Física Teórica UAM/CSIC, Universidad Autónoma de Madrid, E-28049 Madrid (Spain); Departamento de Física Teórica, C-15, Universidad Autónoma de Madrid, E-28049 Madrid (Spain); Okawa, Masanori, E-mail: okawa@sci.hiroshima-u.ac.jp [Graduate School of Science, Hiroshima University, Higashi-Hiroshima, Hiroshima 739-8526 (Japan); Core of Research for the Energetic Universe, Hiroshima University, Higashi-Hiroshima, Hiroshima 739-8526 (Japan)
2016-04-10
We explain how to compute meson masses in the large N limit using the twisted Eguchi–Kawai model. A very simple formula is derived, and we show how it leads in a fast and efficient way to results which are in fairly good agreement with other determinations. The method is easily extensible to reduced models with dynamical fermions based on the twisted reduction idea.
General structure of democratic mass matrix of quark sector in E{sub 6} model
Energy Technology Data Exchange (ETDEWEB)
Ciftci, R., E-mail: rciftci@cern.ch [Ankara (Turkey); Çiftci, A. K., E-mail: abbas.kenan.ciftci@cern.ch [Ankara University, Ankara (Turkey)
2016-03-25
An extension of the Standard Model (SM) fermion sector, which is inspired by the E{sub 6} Grand Unified Theory (GUT) model, might be a good candidate to explain a number of unanswered questions in SM. Existence of the isosinglet quarks might explain great mass difference of bottom and top quarks. Also, democracy on mass matrix elements is a natural approach in SM. In this study, we have given general structure of Democratic Mass Matrix (DMM) of quark sector in E6 model.
Matrix Solution of Coupled Differential Equations and Looped Car Following Models
McCartney, Mark
2008-01-01
A simple mathematical model for the behaviour of how vehicles follow each other along a looped stretch of road is described. The resulting coupled first order differential equations are solved using appropriate matrix techniques and the physical significance of the model is discussed. A number possible classroom exercises are suggested to help…
2D fuzzy anti-de Sitter space from matrix models
Jurman, Danijel; Steinacker, Harold
2014-01-01
We study the fuzzy hyperboloids AdS 2 and dS 2 as brane solutions in matrix models. The unitary representations of SO(2 , 1) required for quantum field theory are identified, and explicit formulae for their realization in terms of fuzzy wavefunctions are given. In a second part, we study the ( A) dS 2 brane geometry and its dynamics, as governed by a suitable matrix model. In particular, we show that trace of the energy-momentum tensor of matter induces transversal perturbations of the brane and of the Ricci scalar. This leads to a linearized form of Henneaux-Teitelboim-type gravity, illustrating the mechanism of emergent gravity in matrix models.
Supersymmetric gauged matrix models from dimensional reduction on a sphere arXiv
Closset, Cyril; Seong, Rak-Kyeong
It was recently proposed that N=1 supersymmetric gauged matrix models have a duality of order four - that is, a quadrality - reminiscent of infrared dualities of SQCD theories in higher dimensions. In this note, we show that the zero-dimensional quadrality proposal can be infered from the two-dimensional Gadde-Gukov-Putrov triality. We consider two-dimensional N=(0,2) SQCD compactified on a sphere with the half-topological twist. For a convenient choice of R-charge, the zero-mode sector on the sphere gives rise to a simple N=1 gauged matrix model. Triality on the sphere then implies a triality relation for the supersymmetric matrix model, which can be completed to the full quadrality.
Reformulation of the Hermitean 1-matrix model as an effective field theory
Energy Technology Data Exchange (ETDEWEB)
Klitz, Alexander
2009-07-15
The formal Hermitean 1-matrix model is shown to be equivalent to an effective field theory. The correlation functions and the free energy of the matrix model correspond directly to the correlation functions and the free energy of the effective field theory. The loop equation of the field theory coupling constants is stated. Despite its length, this loop equation is simpler than the loop equations in the matrix model formalism itself since it does not contain operator inversions in any sense, but consists instead only of derivative operators and simple projection operators. Therefore the solution of the loop equation could be given for an arbitrary number of cuts up to the fifth order in the topological expansion explicitly. Two different methods of obtaining the contributions to the free energy of the higher orders are given, one depending on an operator H and one not depending on it. (orig.)
Eigenview on Jones matrix models of homogeneous anisotropic media
Directory of Open Access Journals (Sweden)
Savenkov S.
2010-06-01
Full Text Available The polarization of light when it passes through optical medium can change as a result of change in the amplitude (dichroism or phase shift (birefringence of the electric vector. The anisotropic properties of media can be determined from these two optical effects. Our main concern here is to revisit the factor of eigenpolarizations and eigenvalues in modeling of polarization properties of homogeneous media and elucidate certain new features in polarization behavior of birefringent and dichroic media.
A Method of Q-Matrix Validation for the Linear Logistic Test Model.
Baghaei, Purya; Hohensinn, Christine
2017-01-01
The linear logistic test model (LLTM) is a well-recognized psychometric model for examining the components of difficulty in cognitive tests and validating construct theories. The plausibility of the construct model, summarized in a matrix of weights, known as the Q-matrix or weight matrix, is tested by (1) comparing the fit of LLTM with the fit of the Rasch model (RM) using the likelihood ratio (LR) test and (2) by examining the correlation between the Rasch model item parameters and LLTM reconstructed item parameters. The problem with the LR test is that it is almost always significant and, consequently, LLTM is rejected. The drawback of examining the correlation coefficient is that there is no cut-off value or lower bound for the magnitude of the correlation coefficient. In this article we suggest a simulation method to set a minimum benchmark for the correlation between item parameters from the Rasch model and those reconstructed by the LLTM. If the cognitive model is valid then the correlation coefficient between the RM-based item parameters and the LLTM-reconstructed item parameters derived from the theoretical weight matrix should be greater than those derived from the simulated matrices.
DEFF Research Database (Denmark)
Yang, Yukay
I consider multivariate (vector) time series models in which the error covariance matrix may be time-varying. I derive a test of constancy of the error covariance matrix against the alternative that the covariance matrix changes over time. I design a new family of Lagrange-multiplier tests against...
A transmission matrix for a fused pair of integrable defects in the sine-Gordon model
Energy Technology Data Exchange (ETDEWEB)
Corrigan, E; Zambon, C, E-mail: edward.corrigan@durham.ac.u, E-mail: cristina.zambon@durham.ac.u [Department of Mathematical Sciences, University of Durham, Durham DH1 3LE (United Kingdom)
2010-08-27
Within the quantum sine-Gordon model a transmission matrix describing the scattering of a soliton with a fused pair of integrable defects is proposed. The result is consistent with the classical picture of scattering and highlights the differences between two defects located at separated points and two defects fused at the same point. Moreover, the analysis reveals how, for certain choices of parameters, both the soliton-soliton and the lightest breather-soliton S-matrices of the sine-Gordon model are embedded within the transmission matrix, supporting an interpretation in which defects may be regarded as soliton constituents.
Numerical transfer-matrix study of a model with competing metastable states
DEFF Research Database (Denmark)
Fiig, T.; Gorman, B.M.; Rikvold, P.A.
1994-01-01
The Blume-Capel model, a three-state lattice-gas model capable of displaying competing metastable states, is investigated in the limit of weak, long-range interactions. The methods used are scalar field theory, a numerical transfer-matrix method, and dynamical Monte Carlo simulations...... 'metastable free-energy density This transfer-matrix approach gives a free-energy cost of nucleation that supports the proportionality relation for the decay rate of the metastable phase T proportional to\\Imf alpha\\, even in cases where two metastable states compete. The picture that emerges from this study...
Lectures on localization and matrix models in supersymmetric Chern-Simons-matter theories
Energy Technology Data Exchange (ETDEWEB)
Marino, Marcos, E-mail: marcos.marino@unige.ch [Departement de Physique Theorique et Section de Mathematiques, Universite de Geneve, Geneve CH-1211 (Switzerland)
2011-11-18
In these lectures, I give a pedagogical presentation of some of the recent progress in supersymmetric Chern-Simons-matter theories, coming from the use of localization and matrix model techniques. The goal is to provide a simple derivation of the exact interpolating function for the free energy of ABJM theory on the three-sphere, which implies in particular the N{sup 3/2} behavior at strong coupling. I explain in detail part of the background needed to understand this derivation, like holographic renormalization, localization of path integrals and large N techniques in matrix models. (topical review)
Meaning-making and the matrix model: does one size really fit all?
Neimeyer, Robert A
2005-09-01
Despite the multifocal complexity of the matrix model (C.R. Snyder & T.R. Elliott, this issue, pp. 1033-1054), its close correspondence with the theoretical dialectics and philosophy of clinical constructivism auger well for its capacity to articulate with existing approaches to graduate education in psychology. In this article points of contact are documented between the two approaches, and a caveat is included about the limits of the matrix model in ensuring greater relevance of clinical training to the settings in which contemporary professionals will work. (c) 2005 Wiley Periodicals, Inc.
Šomvársky, Ján; Dušek, Karel; Dušková-Smrčková, Miroslava
2014-03-01
The class of particulate composites with cross-linked hyperelastic polymer matrix and non-deformable filler particles represents many important biopolymer and engineering materials. At application conditions, the matrix is either in the swollen state, or the swollen state is utilized for matrix characterization. In this contribution, a numerical model for simulation of equilibrium stress-strain and swelling behavior of this composite material was developed based on finite element method using COMSOL Multiphysics® software. In the constitutive equations (Gibbs energy), the elastic contribution is based on statistical-mechanical model of a network composed of freely jointed chains of finite extensibility and polymer-solvent mixing term is derived from the Flory-Huggins lattice model. A perfect adhesion of matrix-to-particle is assumed. The adhesion of matrix to stiff surface generates stress and degree-of-swelling fields in the composite. The existence of these fields determines the mechanical and swelling properties of the composite. Spatial distribution of filler particles in the composite plays an important role.
Delossantos, Aubrey I; Rodriguez, Neil L; Patel, Paarun; Franz, Michael G; Wagner, Christopher T
2013-01-01
We compared fascial wounds repaired with non-cross-linked intact porcine-derived acellular dermal matrix versus primary closure in a large-animal hernia model. Incisional hernias were created in Yucatan pigs and repaired after 3 weeks via open technique with suture-only primary closure or intraperitoneally placed porcine-derived acellular dermal matrix. Progressive changes in mechanical and biological properties of porcine-derived acellular dermal matrix and repair sites were assessed. Porcine-derived acellular dermal matrix–repaired hernias of additional animals were evaluated 2 and 4 weeks post incision to assess porcine-derived acellular dermal matrix regenerative potential and biomechanical changes. Hernias repaired with primary closure showed substantially more scarring and bone hyperplasia along the incision line. Mechanical remodeling of porcine-derived acellular dermal matrix was noted over time. Porcine-derived acellular dermal matrix elastic modulus and ultimate tensile stress were similar to fascia at 6 weeks. The biology of porcine-derived acellular dermal matrix–reinforced animals was more similar to native abdominal wall versus that with primary closure. In this study, porcine-derived acellular dermal matrix–reinforced repairs provided more complete wound healing response compared with primary closure. PMID:24555008
Directory of Open Access Journals (Sweden)
Gary A Monteiro
2013-10-01
Full Text Available We compared fascial wounds repaired with non-cross-linked intact porcine-derived acellular dermal matrix versus primary closure in a large-animal hernia model. Incisional hernias were created in Yucatan pigs and repaired after 3 weeks via open technique with suture-only primary closure or intraperitoneally placed porcine-derived acellular dermal matrix. Progressive changes in mechanical and biological properties of porcine-derived acellular dermal matrix and repair sites were assessed. Porcine-derived acellular dermal matrix–repaired hernias of additional animals were evaluated 2 and 4 weeks post incision to assess porcine-derived acellular dermal matrix regenerative potential and biomechanical changes. Hernias repaired with primary closure showed substantially more scarring and bone hyperplasia along the incision line. Mechanical remodeling of porcine-derived acellular dermal matrix was noted over time. Porcine-derived acellular dermal matrix elastic modulus and ultimate tensile stress were similar to fascia at 6 weeks. The biology of porcine-derived acellular dermal matrix–reinforced animals was more similar to native abdominal wall versus that with primary closure. In this study, porcine-derived acellular dermal matrix–reinforced repairs provided more complete wound healing response compared with primary closure.
Logofet, D O
2010-01-01
Matrix models of discrete-structured population dynamics became a traditional tool in plant and animal demography, aided with developments in the proper mathematics and wide spread of software products, which greatly facilitate creating models in the man-machine dialogue mode, but leave behind the scenes the issue of whether the methods applied are adequate to the problem posed. A principal discrepancy of this kind does appear in a problem to calibrate the projection matrix on observation data of the "identified individuals with uncertain parents" type: simplifying recipes from an ecological software package contradict the idea of polyvariant ontogeny as an adaptation mechanism. The problem becomes solvable if we substitute an extremal adaptation principle for the uncertainty in data as follows: the unknown reproduction rates are assumed to distribute among the reproductive groups in such a way that maximizes the potential growth rate of the model population under the current conditions. In combination with findings from mathematical analysis of a wide class of matrix models, this principle turns the model into a reliable tool to test research hypotheses. Considered as an example is a matrix model (published elsewhere) for the population dynamics of Calamagrostis canescens woodreed, a perennial clonal plant species with a complex, age-stage-based population structure.
Perturbation analysis of transient population dynamics using matrix projection models
DEFF Research Database (Denmark)
Stott, Iain
2016-01-01
Non-stable populations exhibit short-term transient dynamics: size, growth and structure that are unlike predicted long-term asymptotic stable, stationary or equilibrium dynamics. Understanding transient dynamics of non-stable populations is important for designing effective population management...... strategies, predicting the responses of populations to environmental change or disturbance, and understanding population processes and life-history evolution in variable environments. Transient perturbation analyses are vital tools for achieving these aims. They assess how transient dynamics are affected...... of model being analysed, the perturbation structure, the population response of interest, nonlinear response to perturbation, standardization for asymptotic dynamics, the initial population structure, and the time frame of interest. I discuss these with reference to the application of transient...
Search for Gauge-Mediated SUSY Breaking Topologies at $\\sqrt{s}\\sim{189}$ GeV
Barate, R; Ghez, P; Goy, C; Jézéquel, S; Lees, J P; Martin, F; Merle, E; Minard, M N; Pietrzyk, B; Alemany, R; Bravo, S; Casado, M P; Chmeissani, M; Crespo, J M; Fernández, E; Fernández-Bosman, M; Garrido, L; Graugès-Pous, E; Juste, A; Martínez, M; Merino, G; Miquel, R; Mir, L M; Morawitz, P; Pacheco, A; Riu, I; Ruiz, H; Colaleo, A; Creanza, D; De Palma, M; Iaselli, Giuseppe; Maggi, G; Maggi, M; Nuzzo, S; Ranieri, A; Raso, G; Ruggieri, F; Selvaggi, G; Silvestris, L; Tempesta, P; Tricomi, A; Zito, G; Huang, X; Lin, J; Ouyang, Q; Wang, T; Xie, Y; Xu, R; Xue, S; Zhang, J; Zhang, L; Zhao, W; Abbaneo, D; Boix, G; Buchmüller, O L; Cattaneo, M; Cerutti, F; Ciulli, V; Davies, G; Dissertori, G; Drevermann, H; Forty, Roger W; Frank, M; Gianotti, F; Greening, T C; Halley, A W; Hansen, J B; Harvey, J; Janot, P; Jost, B; Kado, M; Leroy, O; Maley, P; Mato, P; Minten, Adolf G; Moutoussi, A; Ranjard, F; Rolandi, Luigi; Schlatter, W D; Schmitt, M; Schneider, O; Spagnolo, P; Tejessy, W; Teubert, F; Tournefier, E; Valassi, Andrea; Wright, A E; Ajaltouni, Ziad J; Badaud, F; Chazelle, G; Deschamps, O; Dessagne, S; Falvard, A; Ferdi, C; Gay, P; Guicheney, C; Henrard, P; Jousset, J; Michel, B; Monteil, S; Montret, J C; Pallin, D; Pascolo, J M; Perret, P; Podlyski, F; Hansen, J D; Hansen, J R; Hansen, P H; Nilsson, B S; Rensch, B; Wäänänen, A; Daskalakis, G; Kyriakis, A; Markou, C; Simopoulou, Errietta; Vayaki, Anna; Blondel, A; Brient, J C; Machefert, F P; Rougé, A; Swynghedauw, M; Tanaka, R; Videau, H L; Focardi, E; Parrini, G; Zachariadou, K; Corden, M; Georgiopoulos, C H; Antonelli, A; Bencivenni, G; Bologna, G; Bossi, F; Campana, P; Capon, G; Chiarella, V; Laurelli, P; Mannocchi, G; Murtas, F; Murtas, G P; Passalacqua, L; Pepé-Altarelli, M; Chalmers, M; Kennedy, J; Lynch, J G; Negus, P; O'Shea, V; Räven, B; Smith, D; Teixeira-Dias, P; Thompson, A S; Ward, J J; Cavanaugh, R J; Dhamotharan, S; Geweniger, C; Hanke, P; Hepp, V; Kluge, E E; Leibenguth, G; Putzer, A; Tittel, K; Werner, S; Wunsch, M; Beuselinck, R; Binnie, David M; Cameron, W; Dornan, Peter J; Girone, M; Goodsir, S M; Marinelli, N; Martin, E B; Nash, J; Nowell, J; Przysiezniak, H; Sciabà, A; Sedgbeer, J K; Thompson, J C; Thomson, E; Williams, M D; Ghete, V M; Girtler, P; Kneringer, E; Kuhn, D; Rudolph, G; Bowdery, C K; Buck, P G; Ellis, G; Finch, A J; Foster, F; Hughes, G; Jones, R W L; Robertson, N A; Smizanska, M; Williams, M I; Giehl, I; Hölldorfer, F; Jakobs, K; Kleinknecht, K; Kröcker, M; Müller, A S; Nürnberger, H A; Quast, G; Renk, B; Rohne, E; Sander, H G; Schmeling, S; Wachsmuth, H W; Zeitnitz, C; Ziegler, T; Bonissent, A; Carr, J; Coyle, P; Ealet, A; Fouchez, D; Tilquin, A; Aleppo, M; Antonelli, M; Gilardoni, S S; Ragusa, F; Büscher, V; Dietl, H; Ganis, G; Hüttmann, K; Lütjens, G; Mannert, C; Männer, W; Moser, H G; Schael, S; Settles, Ronald; Seywerd, H C J; Stenzel, H; Wiedenmann, W; Wolf, G; Azzurri, P; Boucrot, J; Callot, O; Chen, S; Davier, M; Duflot, L; Grivaz, J F; Heusse, P; Jacholkowska, A; Lefrançois, J; Serin, L; Veillet, J J; Videau, I; De Vivie de Régie, J B; Zerwas, D; Bagliesi, G; Boccali, T; Bozzi, C; Calderini, G; Dell'Orso, R; Ferrante, I; Giassi, A; Gregorio, A; Ligabue, F; Marrocchesi, P S; Messineo, A; Palla, Fabrizio; Rizzo, G; Sanguinetti, G; Sguazzoni, G; Tenchini, Roberto; Venturi, A; Verdini, P G; Blair, G A; Coles, J; Cowan, G D; Green, M G; Hutchcroft, D E; Jones, L T; Medcalf, T; Strong, J A; Botterill, David R; Clifft, R W; Edgecock, T R; Norton, P R; Tomalin, I R; Bloch-Devaux, B; Colas, P; Fabbro, B; Faïf, G; Lançon, E; Lemaire, M C; Locci, E; Pérez, P; Rander, J; Renardy, J F; Rosowsky, A; Seager, P; Trabelsi, A; Tuchming, B; Vallage, B; Black, S N; Dann, J H; Loomis, C; Kim, H Y; Konstantinidis, N P; Litke, A M; McNeil, M A; Taylor, G; Booth, C N; Cartwright, S L; Combley, F; Hodgson, P N; Lehto, M H; Thompson, L F; Affholderbach, K; Böhrer, A; Brandt, S; Grupen, Claus; Hess, J; Misiejuk, A; Prange, G; Sieler, U; Borean, C; Giannini, G; Gobbo, B; Pütz, J; Rothberg, J E; Wasserbaech, S R; Williams, R W; Armstrong, S R; Elmer, P; Ferguson, D P S; Gao, Y; González, S; Hayes, O J; Hu, H; Jin, S; Kile, J; McNamara, P A; Nielsen, J; Orejudos, W; Pan, Y B; Saadi, Y; Scott, I J; Walsh, J; Von Wimmersperg-Töller, J H; Wu Sau Lan; Wu, X; Zobernig, G
2001-01-01
Searches for topologies characteristic of Gauge Mediated SUSY Breaking models (GMSB) are performed by analysing 173.6 pb^-1 of data collected at Ecm = 188.6~GeV with the ALEPH detector.These topologies include acoplanar photons, non-pointing single photon, acoplanar leptons, large impact parameter leptons, detached slepton decay vertices, heavy stable charged sleptons and four leptons plus missing energy final states.No evidence for these new phenomena is observed and limits on production cross sections and sparticle masses are derived. A scan of a minimal GMSB parameter space is performed and model dependent lower limits of about 45 GeV/c^2 on the next-to-lightest supersymmetric particle (NLSP) mass and of about 9 TeV on the mass scale parameter Lambda are derived, independently of the NLSP lifetime.
Threshold corrections to dimension-six proton decay operators in non-minimal SUSY SU(5 GUTs
Directory of Open Access Journals (Sweden)
Borut Bajc
2016-09-01
Full Text Available We calculate the high and low scale threshold corrections to the D=6 proton decay mode in supersymmetric SU(5 grand unified theories with higher-dimensional representation Higgs multiplets. In particular, we focus on a missing-partner model in which the grand unified group is spontaneously broken by the 75-dimensional Higgs multiplet and the doublet–triplet splitting problem is solved. We find that in the missing-partner model the D=6 proton decay rate gets suppressed by about 60%, mainly due to the threshold effect at the GUT scale, while the SUSY-scale threshold corrections are found to be less prominent when sfermions are heavy.
Viable and testable SUSY GUTs with Yukawa unification the case of split trilinears
Guadagnoli, Diego; Straub, David M
2009-01-01
We explore general SUSY GUT models with exact third-generation Yukawa unification, but where the requirement of universal soft terms at the GUT scale is relaxed. We consider the scenario in which the breaking of universality inherits from the Yukawa couplings, i.e. is of minimal flavor violating (MFV) type. In particular, the MFV principle allows for a splitting between the up-type and the down-type soft trilinear couplings. We explore the viability of this trilinear splitting scenario by means of a fitting procedure to electroweak observables, quark masses as well as flavor-changing neutral current processes. Phenomenological viability singles out one main scenario. This scenario is characterized by a sizable splitting between the trilinear soft terms and a large mu term. Remarkably, this scenario does not invoke a partial decoupling of the sparticle spectrum, as in the case of universal soft terms, but instead it requires part of the spectrum, notably the lightest stop, the gluino and the lightest charginos...
Search for squark production in R-parity violating SUSY at HERA
Stanco, L
2001-01-01
Searches for squarks produced via R-parity violating interactions in e /sup +/p collisions at a center-of-mass energy of 300 GeV have been performed at HERA using the two detectors, H1 and ZEUS, and an integrated luminosity of 37 and 48 pb/sup -1/, respectively. Squarks produced in e/sup +/-quark fusion could decay either to e/sup +/-quark or via a supersymmetric gauge decay, resulting in many possible final states. The signal has been searched for in most of R-parity violating decays and gauge decays of the squarks. No evidence for squark production was found and limits were set on the R-parity violating coupling as a function of the squark mass and the SUSY parameters, extending to domains unexplored in other direct or indirect searches. For a fixed value of the coupling, HERA results are interpreted for the first time in terms of constraints on the parameters of the mSUGRA model.
Matrix models from localization of five-dimensional supersymmetric noncommutative U(1) gauge theory
Energy Technology Data Exchange (ETDEWEB)
Lee, Bum-Hoon [Department of Physics, Sogang University,Seoul 04107 (Korea, Republic of); Asia Pacific Center for Theoretical Physics, POSTECH,Pohang, Gyeongbuk 37673 (Korea, Republic of); Center for Quantum Spacetime, Sogang University,Seoul 04107 (Korea, Republic of); Ro, Daeho [Asia Pacific Center for Theoretical Physics, POSTECH,Pohang, Gyeongbuk 37673 (Korea, Republic of); Yang, Hyun Seok [Center for Quantum Spacetime, Sogang University,Seoul 04107 (Korea, Republic of)
2017-01-10
We study localization of five-dimensional supersymmetric U(1) gauge theory on S{sup 3}×ℝ{sub θ}{sup 2} where ℝ{sub θ}{sup 2} is a noncommutative (NC) plane. The theory can be isomorphically mapped to three-dimensional supersymmetric U(N→∞) gauge theory on S{sup 3} using the matrix representation on a separable Hilbert space on which NC fields linearly act. Therefore the NC space ℝ{sub θ}{sup 2} allows for a flexible path to derive matrix models via localization from a higher-dimensional supersymmetric NC U(1) gauge theory. The result shows a rich duality between NC U(1) gauge theories and large N matrix models in various dimensions.
Linear programming models and methods of matrix games with payoffs of triangular fuzzy numbers
Li, Deng-Feng
2016-01-01
This book addresses two-person zero-sum finite games in which the payoffs in any situation are expressed with fuzzy numbers. The purpose of this book is to develop a suite of effective and efficient linear programming models and methods for solving matrix games with payoffs in fuzzy numbers. Divided into six chapters, it discusses the concepts of solutions of matrix games with payoffs of intervals, along with their linear programming models and methods. Furthermore, it is directly relevant to the research field of matrix games under uncertain economic management. The book offers a valuable resource for readers involved in theoretical research and practical applications from a range of different fields including game theory, operational research, management science, fuzzy mathematical programming, fuzzy mathematics, industrial engineering, business and social economics. .
Split-Family SUSY, U(2)^5 Flavour Symmetry and Neutrino Physics
Jones-Pérez, Joel
2014-01-01
In split-family SUSY, one can use a U(2)^3 symmetry to protect flavour observables in the quark sector from SUSY contributions. However, attempts to extend this procedure to the lepton sector by using an analogous U(2)^5 symmetry fail to reproduce the neutrino data without introducing some form of fine-tuning. In this work, we solve this problem by shifting the U(2)^2 symmetry acting on leptons towards the second and third generations. This allows neutrino data to be reproduced without much difficulties, as well as protecting the leptonic flavour observables from SUSY. Key signatures are a $\\mu\\to e\\gamma$ branching ratio possibly observable in the near future, as well as having selectrons as the lightest sleptons.
Fracture-Based Mesh Size Requirements for Matrix Cracks in Continuum Damage Mechanics Models
Leone, Frank A.; Davila, Carlos G.; Mabson, Gerald E.; Ramnath, Madhavadas; Hyder, Imran
2017-01-01
This paper evaluates the ability of progressive damage analysis (PDA) finite element (FE) models to predict transverse matrix cracks in unidirectional composites. The results of the analyses are compared to closed-form linear elastic fracture mechanics (LEFM) solutions. Matrix cracks in fiber-reinforced composite materials subjected to mode I and mode II loading are studied using continuum damage mechanics and zero-thickness cohesive zone modeling approaches. The FE models used in this study are built parametrically so as to investigate several model input variables and the limits associated with matching the upper-bound LEFM solutions. Specifically, the sensitivity of the PDA FE model results to changes in strength and element size are investigated.
Performance modeling and optimization of sparse matrix-vector multiplication on NVIDIA CUDA platform
Xu, S.; Xue, W.; Lin, H.X.
2011-01-01
In this article, we discuss the performance modeling and optimization of Sparse Matrix-Vector Multiplication (SpMV) on NVIDIA GPUs using CUDA. SpMV has a very low computation-data ratio and its performance is mainly bound by the memory bandwidth. We propose optimization of SpMV based on ELLPACK from
Longbiao, Li
2015-12-01
The stress-strain curves of fiber - reinforced ceramic - matrix composites (CMCs) exhibit obvious non-linear behaviour under tensile loading. The occurrence of multiple damage mechanisms, i.e., matrix multicracking, fiber/matrix interface debonding and fibers fracture, is the mainly reason for the non-linear characteristic. The micromechanics approach has been developed to predict the tensile stress-strain curves of unidirectional, cross-ply and woven CMCs. The shear-lag model was used to describe the micro stress field of the damaged composite. The damage models were used to determine the evolution of micro damage parameters, i.e., matrix crack spacing, interface debonded length and broken fibers fraction. By combining the shear-lag model with damage models and considering the effect of transverse multicracking in the 90° plies or transverse yarns in cross-ply or woven CMCs, the tensile stress-strain curves of unidirectional, cross-ply, 2D and 2.5D woven CMCs have been predicted. The results agreed with experimental data.
Power-law expansion of the Universe from the bosonic Lorentzian type IIB matrix model
Energy Technology Data Exchange (ETDEWEB)
Ito, Yuta [Department of Particle and Nuclear Physics,Graduate University for Advanced Studies (SOKENDAI),Tsukuba, Ibaraki 305-0801 (Japan); Nishimura, Jun [Department of Particle and Nuclear Physics,Graduate University for Advanced Studies (SOKENDAI),Tsukuba, Ibaraki 305-0801 (Japan); High Energy Accelerator Research Organization (KEK),Tsukuba, Ibaraki 305-0801 (Japan); Tsuchiya, Asato [Department of Physics, Shizuoka University,836 Ohya, Suruga-ku, Shizuoka 422-8529 (Japan)
2015-11-10
Recent studies on the Lorentzian version of the type IIB matrix model show that (3+1)D expanding universe emerges dynamically from (9+1)D space-time predicted by superstring theory. Here we study a bosonic matrix model obtained by omitting the fermionic matrices. With the adopted simplification and the usage of a large-scale parallel computer, we are able to perform Monte Carlo calculations with matrix size up to N=512, which is twenty times larger than that used previously for the studies of the original model. When the matrix size is larger than some critical value N{sub c}≃110, we find that (3+1)D expanding universe emerges dynamically with a clear large-N scaling property. Furthermore, the observed increase of the spatial extent with time t at sufficiently late times is consistent with a power-law behavior t{sup 1/2}, which is reminiscent of the expanding behavior of the Friedmann-Robertson-Walker universe in the radiation dominated era. We discuss possible implications of this result on the original supersymmetric model including fermionic matrices.
MODELING OF INTERACTION LAYER GROWTH BETWEEN U-Mo PARTICLES AND AN Al MATRIX
Directory of Open Access Journals (Sweden)
YEON SOO KIM
2013-12-01
Full Text Available Interaction layer growth between U-Mo alloy fuel particles and Al in a dispersion fuel is a concern due to the volume expansion and other unfavorable irradiation behavior of the interaction product. To reduce interaction layer (IL growth, a small amount of Si is added to the Al. As a result, IL growth is affected by the Si content in the Al matrix. In order to predict IL growth during fabrication and irradiation, empirical models were developed. For IL growth prediction during fabrication and any follow-on heating process before irradiation, out-of-pile heating test data were used to develop kinetic correlations. Two out-of-pile correlations, one for the pure Al matrix and the other for the Al matrix with Si addition, respectively, were developed, which are Arrhenius equations that include temperature and time. For IL growth predictions during irradiation, the out-of-pile correlations were modified to include a fission-rate term to consider fission enhanced diffusion, and multiplication factors to incorporate the Si addition effect and the effect of the Mo content. The in-pile correlation is applicable for a pure Al matrix and an Al matrix with the Si content up to 8 wt%, for fuel temperatures up to 200 °C, and for Mo content in the range of 6 – 10wt%. In order to cover these ranges, in-pile data were included in modeling from various tests, such as the US RERTR-4, -5, -6, -7 and -9 tests and Korea's KOMO-4 test, that were designed to systematically examine the effects of the fission rate, temperature, Si content in Al matrix, and Mo content in U-Mo particles. A model converting the IL thickness to the IL volume fraction in the meat was also developed.
Analysis of α-12C elastic scattering at intermediate energies by the S-matrix model
Berezhnoy, Yu. A.; Onyshchenko, G. M.; Pilipenko, V. V.
The results of calculations of differential cross-sections for α-12C elastic scattering by the S-matrix model are presented for 10 energy values in the energy range 65MeV ≤ Eα ≤ 386MeV in a wide range of scattering angles. The behavior of various scattering characteristics as functions of the projectile energy is analyzed. It is shown that the chosen parametrization of S-matrix allows describing correctly the Fraunhofer oscillations of the cross-sections in the region of small scattering angles and the rainbow scattering pattern in the region of sufficiently large angles.
Caballero, David; Samitier, Josep
2017-02-01
The interaction of cells with their natural environment influences a large variety of cellular phenomena, including cell adhesion, proliferation, and migration. The complex extracellular matrix network has challenged the attempts to replicate in vitro the heterogeneity of the cell environment and has threatened, in general, the relevance of in vitro studies. In this work, we describe a new and extremely versatile approach to generate native-like extracellular matrices with controlled morphologies for the in vitro study of cellular processes. This general approach combines the confluent culture of fibroblasts with microfabricated guiding templates to direct the three-dimensional growth of well-defined extracellular networks which recapitulate the structural and biomolecular complexity of features typically found in vivo. To evaluate its performance, we studied fundamental cellular processes, including cell cytoskeleton organization, cell-matrix adhesion, proliferation, and protrusions morphodynamics. In all cases, we found striking differences depending on matrix architecture and, in particular, when compared to standard two-dimensional environments. We also assessed whether the engineered matrix networks influenced cell migration dynamics and locomotion strategy, finding enhanced migration efficiency for cells seeded on aligned matrices. Altogether, our methodology paves the way to the development of high-performance models of the extracellular matrix for potential applications in tissue engineering, diagnosis, or stem-cell biology.
UA(1) breaking and phase transition in chiral random matrix model
Sano, T.; Fujii, H.; Ohtani, M
2009-01-01
We propose a chiral random matrix model which properly incorporates the flavor-number dependence of the phase transition owing to the \\UA(1) anomaly term. At finite temperature, the model shows the second-order phase transition with mean-field critical exponents for two massless flavors, while in the case of three massless flavors the transition turns out to be of the first order. The topological susceptibility satisfies the anomalous \\UA(1) Ward identity and decreases gradually with the temp...
Modeling the modified drug release from curved shape drug delivery systems - Dome Matrix®.
Caccavo, D; Barba, A A; d'Amore, M; De Piano, R; Lamberti, G; Rossi, A; Colombo, P
2017-12-01
The controlled drug release from hydrogel-based drug delivery systems is a topic of large interest for research in pharmacology. The mathematical modeling of the behavior of these systems is a tool of emerging relevance, since the simulations can be of use in the design of novel systems, in particular for complex shaped tablets. In this work a model, previously developed, was applied to complex-shaped oral drug delivery systems based on hydrogels (Dome Matrix®). Furthermore, the model was successfully adopted in the description of drug release from partially accessible Dome Matrix® systems (systems with some surfaces coated). In these simulations, the erosion rate was used asa fitting parameter, and its dependence upon the surface area/volume ratio and upon the local fluid dynamics was discussed. The model parameters were determined by comparison with the drug release profile from a cylindrical tablet, then the model was successfully used for the prediction of the drug release from a Dome Matrix® system, for simple module configuration and for module assembled (void and piled) configurations. It was also demonstrated that, given the same initial S/V ratio, the drug release is independent upon the shape of the tablets but it is only influenced by the S/V evolution. The model reveals itself able to describe the observed phenomena, and thus it can be of use for the design of oral drug delivery systems, even if complex shaped. Copyright © 2017 Elsevier B.V. All rights reserved.
Wang, Dong; Vo, Nam V; Sowa, Gwendolyn A; Hartman, Robert A; Ngo, Kevin; Choe, So Ra; Witt, William T; Dong, Qing; Lee, Joon Y; Niedernhofer, Laura J; Kang, James D
2011-02-01
Bupivacaine is a local anesthetic commonly used for back pain management in interventional procedures. Cytotoxic effects of bupivacaine have been reported in articular cartilage and, recently, in intervertebral disc cell culture. However, the relevance of these effects to discs in vivo remains unclear. This study examines the effect of bupivacaine on disc cell metabolism using an organotypic culture model system that mimics the in vivo environment. To assess the effect of bupivacaine on disc cell viability and matrix protein synthesis using an organotypic model system and to determine whether this anesthetic has toxic effects. Mouse intervertebral discs were isolated and maintained ex vivo in an organotypic culture then exposed to clinically relevant concentrations of bupivacaine, and the impact on disc cell viability and matrix proteoglycan (PG) and collagen syntheses were measured in the presence and absence of the drug. Mouse functional spine units (FSUs) were isolated from the lumbar spines of 10-week-old mice. Cell viability was assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Total PG and collagen syntheses were determined by measuring the incorporation of radioactive (35)S-sulfate and (3)H-l-proline into PG and collagen, respectively. Organotypic cultures of mouse FSUs were exposed to different concentrations (0%-0.5%) of bupivacaine for variable amounts of time (0-2 hours). Cell viability within disc tissue was quantified by MTT staining and histologic assay. Matrix protein synthesis was measured by incorporation of radioactive (35)S-sulfate (for PG synthesis) and (3)H-l-proline (for collagen synthesis). Untreated mouse disc organs were maintained in culture for up to 1 month with minimal changes in tissue histology, cell viability, and matrix protein synthesis. Exposure to bupivacaine decreased cell viability in a dose- and time-dependent manner. Exposure to bupivacaine at concentrations less than or equal to 0.25% did
Development of a hybrid wave based-transfer matrix model for sound transmission analysis.
Dijckmans, A; Vermeir, G
2013-04-01
In this paper, a hybrid wave based-transfer matrix model is presented that allows for the investigation of the sound transmission through finite multilayered structures placed between two reverberant rooms. The multilayered structure may consist of an arbitrary configuration of fluid, elastic, or poro-elastic layers. The field variables (structural displacements and sound pressures) are expanded in terms of structural and acoustic wave functions. The boundary and continuity conditions in the rooms determine the participation factors in the pressure expansions. The displacement of the multilayered structure is determined by the mechanical impedance matrix, which gives a relation between the pressures and transverse displacements at both sides of the structure. The elements of this matrix are calculated with the transfer matrix method. First, the hybrid model is numerically validated. Next a comparison is made with sound transmission loss measurements of a hollow brick wall and a sandwich panel. Finally, numerical simulations show the influence of structural damping, room dimensions and plate dimensions on the sound transmission loss of multilayered structures.
Anagnostopoulos, Konstantinos N; Nishimura, Jun
2012-01-01
The IKKT or IIB matrix model has been postulated to be a non perturbative definition of superstring theory. It has the attractive feature that spacetime is dynamically generated, which makes possible the scenario of dynamical compactification of extra dimensions, which in the Euclidean model manifests by spontaneously breaking the SO(10) rotational invariance (SSB). In this work we study using Monte Carlo simulations the 6 dimensional version of the Euclidean IIB matrix model. Simulations are found to be plagued by a strong complex action problem and the factorization method is used for effective sampling and computing expectation values of the extent of spacetime in various dimensions. Our results are consistent with calculations using the Gaussian Expansion method which predict SSB to SO(3) symmetric vacua, a finite universal extent of the compactified dimensions and finite spacetime volume.
Mathematical model of water transport in Bacon and alkaline matrix-type hydrogen-oxygen fuel cells
Prokopius, P. R.; Easter, R. W.
1972-01-01
Based on general mass continuity and diffusive transport equations, a mathematical model was developed that simulates the transport of water in Bacon and alkaline-matrix fuel cells. The derived model was validated by using it to analytically reproduce various Bacon and matrix-cell experimental water transport transients.
A framework for studying transient dynamics of population projection matrix models
DEFF Research Database (Denmark)
Stott, Iain; Townley, Stuart; Hodgson, David James
2011-01-01
Empirical models are central to effective conservation and population management, and should be predictive of real-world dynamics. Available modelling methods are diverse, but analysis usually focuses on long-term dynamics that are unable to describe the complicated short-term time series that can...... arise even from simple models following ecological disturbances or perturbations. Recent interest in such transient dynamics has led to diverse methodologies for their quantification in density-independent, time-invariant population projection matrix (PPM) models, but the fragmented nature...
Numerical modeling of solid-phase microextraction: binding matrix effect on equilibrium time.
Alam, Md Nazmul; Ricardez-Sandoval, Luis; Pawliszyn, Janusz
2015-10-06
Solid-phase microextraction (SPME) is a well-known sampling and sample preparation technique used for a wide variety of analytical applications. As there are various complex processes taking place at the time of extraction that influence the parameters of optimum extraction, a mathematical model and computational simulation describing the SPME process is required for experimentalists to understand and implement the technique without performing multiple costly and time-consuming experiments in the laboratory. In this study, a mechanistic mathematical model for the processes occurring in SPME extraction of analyte(s) from an aqueous sample medium is presented. The proposed mechanistic model was validated with previously reported experimental data from three different sources. Several key factors that affect the extraction kinetics, such as sample agitation, fiber coating thickness, and presence of a binding matrix component, are discussed. More interestingly, for the first time, shorter or longer equilibrium times in the presence of a binding matrix component were explained with the help of an asymptotic analysis. Parameters that contribute to the variation of the equilibrium times are discussed, with the assumption that one binding matrix component is present in a static sample. Numerical simulation results show that the proposed model captures the phenomena occurring in SPME, leading to a clearer understanding of this process. Therefore, the currently presented model can be used to identify optimum experimental parameters without the need to perform a large number of experiments in the laboratory.
Telfeyan, Katherine; Ware, S Doug; Reimus, Paul W; Birdsell, Kay H
2018-02-01
Diffusion cell and diffusion wafer experiments were conducted to compare methods for estimating effective matrix diffusion coefficients in rock core samples from Pahute Mesa at the Nevada Nuclear Security Site (NNSS). A diffusion wafer method, in which a solute diffuses out of a rock matrix that is pre-saturated with water containing the solute, is presented as a simpler alternative to the traditional through-diffusion (diffusion cell) method. Both methods yielded estimates of effective matrix diffusion coefficients that were within the range of values previously reported for NNSS volcanic rocks. The difference between the estimates of the two methods ranged from 14 to 30%, and there was no systematic high or low bias of one method relative to the other. From a transport modeling perspective, these differences are relatively minor when one considers that other variables (e.g., fracture apertures, fracture spacings) influence matrix diffusion to a greater degree and tend to have greater uncertainty than effective matrix diffusion coefficients. For the same relative random errors in concentration measurements, the diffusion cell method yields effective matrix diffusion coefficient estimates that have less uncertainty than the wafer method. However, the wafer method is easier and less costly to implement and yields estimates more quickly, thus allowing a greater number of samples to be analyzed for the same cost and time. Given the relatively good agreement between the methods, and the lack of any apparent bias between the methods, the diffusion wafer method appears to offer advantages over the diffusion cell method if better statistical representation of a given set of rock samples is desired. Copyright © 2018 Elsevier B.V. All rights reserved.
High scale parity invariance as a solution to the SUSY CP problem ...
Indian Academy of Sciences (India)
anism automatic in the theory. The minimal version of this theory also provides an explanation of ... cannot be rotated away by. *This talk is based on work done in collaboration with K S Babu and B Dutta. ... ¯Г. The low energy theory in this case is MSSM, but without the SUSY CP problem and with its parameters restricted ...
Decoupling limit and throat geometry of non-susy D3 brane
Directory of Open Access Journals (Sweden)
Kuntal Nayek
2017-03-01
Full Text Available Recently it has been shown by us that, like BPS Dp branes, bulk gravity gets decoupled from the brane even for the non-susy Dp branes of type II string theories indicating a possible extension of AdS/CFT correspondence for the non-supersymmetric case. In that work, the decoupling of gravity on the non-susy Dp branes has been shown numerically for the general case as well as analytically for some special case. Here we discuss the decoupling limit and the throat geometry of the non-susy D3 brane when the charge associated with the brane is very large. We show that in the decoupling limit the throat geometry of the non-susy D3 brane, under appropriate coordinate change, reduces to the Constable–Myers solution and thus confirming that this solution is indeed the holographic dual of a (non-gravitational gauge theory discussed there. We also show that when one of the parameters of the solution takes a specific value, it reduces, under another coordinate change, to the five-dimensional solution obtained by Csaki and Reece, again confirming its gauge theory interpretation.
Decoupling limit and throat geometry of non-susy D3 brane
Energy Technology Data Exchange (ETDEWEB)
Nayek, Kuntal, E-mail: kuntal.nayek@saha.ac.in; Roy, Shibaji, E-mail: shibaji.roy@saha.ac.in
2017-03-10
Recently it has been shown by us that, like BPS Dp branes, bulk gravity gets decoupled from the brane even for the non-susy Dp branes of type II string theories indicating a possible extension of AdS/CFT correspondence for the non-supersymmetric case. In that work, the decoupling of gravity on the non-susy Dp branes has been shown numerically for the general case as well as analytically for some special case. Here we discuss the decoupling limit and the throat geometry of the non-susy D3 brane when the charge associated with the brane is very large. We show that in the decoupling limit the throat geometry of the non-susy D3 brane, under appropriate coordinate change, reduces to the Constable–Myers solution and thus confirming that this solution is indeed the holographic dual of a (non-gravitational) gauge theory discussed there. We also show that when one of the parameters of the solution takes a specific value, it reduces, under another coordinate change, to the five-dimensional solution obtained by Csaki and Reece, again confirming its gauge theory interpretation.
Kas kool vajab kõrvalpilke? / Meelis Kond, Peep Susi, Marge Lepik ... [jt.
2009-01-01
Küsimusele vastavad Tallinna haridusameti hariduskorralduse teenistuse direktor Meelis Kond, Lihula gümnaasiumi direktor Peep Susi, Lääne-Viru maavalitsuse haridus- ja kultuuriosakonna juhataja Marge Lepik, Oru kooli direktor Andres Kampmann ja Haapsalu Nikolai kooli direktor Aive Saadjärv
sUsY dark matter-a collider physicist's perspective
Indian Academy of Sciences (India)
Home; Journals; Pramana – Journal of Physics; Volume 62; Issue 2. SUSY dark matter — a collider physicist's perspective. Mihoko M Nojiri. Volume 62 Issue 2 February 2004 pp 335-346. Fulltext. Click here to view fulltext PDF. Permanent link: http://www.ias.ac.in/article/fulltext/pram/062/02/0335-0346. Keywords.
Concordia ülikooli õppejõud nõuavad rektor Mart Susi lahkumist / Andri Maimets
Maimets, Andri
2003-01-01
Concordia Ülikooli õppejõud ja tudengid esitasid senisele rektorile Mart Susile palve oma kohalt lahkuda, nad ei pea õigeks, et ülikooli juhib ülikooli rahaga patustanud inimene. Susi väitis üliõpilaste ees peetud pressikonverentsil, et jutud ülikooli võlgadest ja tema enda ametikoha kuritarvitustest ei vasta tõele
Susi takistab Concordia ülikooli tööd
2003-01-01
Concordia ülikooli endine rektor Mart Susi pole astunud konkreetseid samme õppetöö jätkuvuse tagamiseks ega oma volituste üleandmiseks, vaid üritab võimu taas enda kätte koondada ja on alates märtsi lõpust otsinud võimalusi pankrotiprotsessi peatamiseks
Möbius invariant BFKL equation for the adjoint representation in N=4 SUSY
Energy Technology Data Exchange (ETDEWEB)
Fadin, V.S., E-mail: fadin@inp.nsk.su [Budker Institute of Nuclear Physics of SD RAS, 630090 Novosibirsk (Russian Federation); Novosibirsk State University, 630090 Novosibirsk (Russian Federation); Fiore, R., E-mail: roberto.fiore@cs.infn.it [Dipartimento di Fisica, Università della Calabria, and Istituto Nazionale di Fisica Nucleare, Gruppo collegato di Cosenza, Arcavacata di Rende, I-87036 Cosenza (Italy); Lipatov, L.N., E-mail: lipatov@thd.pnpi.spb.ru [Petersburg Nuclear Physics Institute and St. Petersburg State University, Gatchina, 188300 St. Petersburg (Russian Federation); Papa, A., E-mail: alessandro.papa@cs.infn.it [Dipartimento di Fisica, Università della Calabria, and Istituto Nazionale di Fisica Nucleare, Gruppo collegato di Cosenza, Arcavacata di Rende, I-87036 Cosenza (Italy)
2013-09-01
It is shown that in the next-to-leading approximation of N=4 SUSY the BFKL equation for two-gluon composite states in the adjoint representation of the gauge group can be reduced to a form which is invariant under Möbius transformation in the momentum space. The corresponding similarity transformation of its integral kernel is constructed in an explicit way.
Analyzing the success of T-matrix diagrammatic theories in representing a modified Hubbard model.
Pisarski, P; Gooding, R J
2011-05-25
We present a systematic study of various forms of renormalization that can be applied in the calculation of the self-energy of the Hubbard model within the T-matrix approximation. We compare the exact solutions of the attractive and repulsive Hubbard models, for linear chains of lengths up to eight sites, with all possible taxonomies of the T-matrix approximation. For the attractive Hubbard model, the success of a minimally self-consistent theory found earlier in the atomic limit (Verga et al 2005 Phys. Rev. B 71 155111) is not maintained for finite clusters unless one is in the very strong correlation limit. For the repulsive model, in the weak correlation limit at low electronic densities-that is, where one would expect a self-consistent T-matrix theory to be adequate-we find the fully renormalized theory to be most successful. In our studies we employ a modified Hubbard interaction that eliminates all Hartree diagrams, an idea which was proposed earlier (Zlatić et al 2000 Phys. Rev. B 63 035104).
Directory of Open Access Journals (Sweden)
E DU
2014-01-01
Full Text Available We developed a model to describe polarized photon scattering in biological tissues. In this model, tissues are simplified to a mixture of scatterers and surrounding medium. There are two types of scatterers in the model: solid spheres and infinitely long solid cylinders. Variables related to the scatterers include: the densities and sizes of the spheres and cylinders, the orientation and angular distribution of cylinders. Variables related to the surrounding medium include: the refractive index, absorption coefficient and birefringence. In this paper, as a development we introduce an optical activity effect to the model. By comparing experiments and Monte Carlo simulations, we analyze the backscattering Mueller matrix patterns of several tissue-like media, and summarize the different effects coming from anisotropic scattering and optical properties. In addition, we propose a possible method to extract the optical activity values for tissues. Both the experimental and simulated results show that, by analyzing the Mueller matrix patterns, the microstructure and optical properties of the medium can be obtained. The characteristic features of Mueller matrix patterns are potentially powerful tools for studying the contrast mechanisms of polarization imaging for medical diagnosis.
Gluino reach and mass extraction at the LHC in radiatively-driven natural SUSY
Energy Technology Data Exchange (ETDEWEB)
Baer, Howard; Savoy, Michael; Sengupta, Dibyashree [University of Oklahoma, Department of Physics and Astronomy, Norman, OK (United States); Barger, Vernon [University of Wisconsin, Department of Physics, Madison, WI (United States); Gainer, James S.; Tata, Xerxes [University of Hawaii, Department of Physics and Astronomy, Honolulu, HI (United States); Huang, Peisi [University of Chicago, Enrico Fermi Institute, Chicago, IL (United States); HEP Division, Argonne National Laboratory, Argonne, IL (United States); Texas A and M University, Mitchell Institute for Fundamental Physics and Astronomy, College Station, TX (United States)
2017-07-15
Radiatively-driven natural SUSY (RNS) models enjoy electroweak naturalness at the 10% level while respecting LHC sparticle and Higgs mass constraints. Gluino and top-squark masses can range up to several TeV (with other squarks even heavier) but a set of light Higgsinos are required with mass not too far above m{sub h} ∝ 125 GeV. Within the RNS framework, gluinos dominantly decay via g → tt{sub 1}{sup *}, anti tt{sub 1} → t anti tZ{sub 1,2} or t anti bW{sub 1}{sup -} + c.c., where the decay products of the higgsino-like W{sub 1} and Z{sub 2} are very soft. Gluino pair production is, therefore, signaled by events with up to four hard b-jets and large E{sub T}. We devise a set of cuts to isolate a relatively pure gluino sample at the (high-luminosity) LHC and show that in the RNS model with very heavy squarks, the gluino signal will be accessible for m{sub g} < 2400 (2800) GeV for an integrated luminosity of 300 (3000) fb{sup -1}. We also show that the measurement of the rate of gluino events in the clean sample mentioned above allows for a determination of m{sub g} with a statistical precision of 2-5% (depending on the integrated luminosity and the gluino mass) over the range of gluino masses where a 5σ discovery is possible at the LHC. (orig.)
Shan, Ying
Flexible matrix composites (FMCs) utilize the high elongation capability of elastomers such as polyurethane to withstand large strains in the direction transverse to the fiber reinforcement while retaining strength and stiffness in the longitudinal direction. FMCs are highly anisotropic and can therefore be tailored to achieve distinctive mechanical characteristics that are difficult to obtain using conventional rigid matrix composites. In the current study, the potential of using an FMC to construct a flexurally-soft, torsionally-stiff driveshaft is examined. The FMC selected for the current investigation is a carbon fiber/polyurethane matrix material system. Both quasi-static and dynamic tests have been performed to characterize the properties of the FMC material. By modeling viscoelastic FMC lamina properties with a fractional derivative approach, a novel damping model that accounts for the frequency and temperature dependence of the FMC material is developed. This is the first time fractional derivative model has been applied to a fiber composite. Good agreement between the damping model and experimental data for angle-ply tubes was obtained. Based on the validated damping model, a self-heating model to predict the temperature increase caused by internal damping of a FMC shaft under misaligned rotation is also proposed. A laboratory-scale, misaligned FMC shaft rotation test stand was built to validate the proposed model. Good agreement is shown between the self-heating model predictions and experiment results. This model can be valuable in the selection of constituent materials for FMCs and also in the design of FMC shafts. Preliminary fatigue test results show that FMC materials have potentially good fatigue performance in shaft applications.
Directory of Open Access Journals (Sweden)
Mihaela Poienar
2014-09-01
Full Text Available The clock hour figure mathematical model of a threephase transformer can be expressed, in the most plain form, through a 3X3 square matrix, called code matrix. The lines position reflect the modification in the high voltage windings terminal and the columns position reflect the modification in the low voltage winding terminal. The main changes on the transformer winding terminal are: the circular permutation of connection between windings; terminal supply reversal; reverse direction for the phase winding wrapping; reversal the beginning with the end for a phase winding; the connection conversion from N in Z between phase winding or inverse. The analytical form of these changes actually affect the configuration of the mathematical model expressed through a transformations diagram proposed and analyzed in two ways: bipolar version and unipolar version (fanwise. In the end of the paper are presented about the practical exploitation of the transformations diagram.
Refined open intersection numbers and the Kontsevich-Penner matrix model
Alexandrov, Alexander; Buryak, Alexandr; Tessler, Ran J.
2017-03-01
A study of the intersection theory on the moduli space of Riemann surfaces with boundary was recently initiated in a work of R. Pandharipande, J.P. Solomon and the third author, where they introduced open intersection numbers in genus 0. Their construction was later generalized to all genera by J.P. Solomon and the third author. In this paper we consider a refinement of the open intersection numbers by distinguishing contributions from surfaces with different numbers of boundary components, and we calculate all these numbers. We then construct a matrix model for the generating series of the refined open intersection numbers and conjecture that it is equivalent to the Kontsevich-Penner matrix model. An evidence for the conjecture is presented. Another refinement of the open intersection numbers, which describes the distribution of the boundary marked points on the boundary components, is also discussed.
Refined open intersection numbers and the Kontsevich-Penner matrix model
Energy Technology Data Exchange (ETDEWEB)
Alexandrov, Alexander [Center for Geometry and Physics, Institute for Basic Science (IBS),Pohang 37673 (Korea, Republic of); Centre de Recherches Mathématiques (CRM), Université de Montréal,Montréal (Canada); Department of Mathematics and Statistics, Concordia University,Montréal (Canada); Institute for Theoretical and Experimental Physics (ITEP),Moscow (Russian Federation); Buryak, Alexandr [Department of Mathematics, ETH Zurich, Zurich (Switzerland); Tessler, Ran J. [Institute for Theoretical Studies, ETH Zurich,Zurich (Switzerland)
2017-03-23
A study of the intersection theory on the moduli space of Riemann surfaces with boundary was recently initiated in a work of R. Pandharipande, J.P. Solomon and the third author, where they introduced open intersection numbers in genus 0. Their construction was later generalized to all genera by J.P. Solomon and the third author. In this paper we consider a refinement of the open intersection numbers by distinguishing contributions from surfaces with different numbers of boundary components, and we calculate all these numbers. We then construct a matrix model for the generating series of the refined open intersection numbers and conjecture that it is equivalent to the Kontsevich-Penner matrix model. An evidence for the conjecture is presented. Another refinement of the open intersection numbers, which describes the distribution of the boundary marked points on the boundary components, is also discussed.
Lyu, Jingyuan; Nakarmi, Ukash; Zhang, Chaoyi; Ying, Leslie
2016-05-01
This paper presents a new approach to highly accelerated dynamic parallel MRI using low rank matrix completion, partial separability (PS) model. In data acquisition, k-space data is moderately randomly undersampled at the center kspace navigator locations, but highly undersampled at the outer k-space for each temporal frame. In reconstruction, the navigator data is reconstructed from undersampled data using structured low-rank matrix completion. After all the unacquired navigator data is estimated, the partial separable model is used to obtain partial k-t data. Then the parallel imaging method is used to acquire the entire dynamic image series from highly undersampled data. The proposed method has shown to achieve high quality reconstructions with reduction factors up to 31, and temporal resolution of 29ms, when the conventional PS method fails.
Directory of Open Access Journals (Sweden)
Qunyi Xie
2016-01-01
Full Text Available Content-based image retrieval has recently become an important research topic and has been widely used for managing images from repertories. In this article, we address an efficient technique, called MNGS, which integrates multiview constrained nonnegative matrix factorization (NMF and Gaussian mixture model- (GMM- based spectral clustering for image retrieval. In the proposed methodology, the multiview NMF scheme provides competitive sparse representations of underlying images through decomposition of a similarity-preserving matrix that is formed by fusing multiple features from different visual aspects. In particular, the proposed method merges manifold constraints into the standard NMF objective function to impose an orthogonality constraint on the basis matrix and satisfy the structure preservation requirement of the coefficient matrix. To manipulate the clustering method on sparse representations, this paper has developed a GMM-based spectral clustering method in which the Gaussian components are regrouped in spectral space, which significantly improves the retrieval effectiveness. In this way, image retrieval of the whole database translates to a nearest-neighbour search in the cluster containing the query image. Simultaneously, this study investigates the proof of convergence of the objective function and the analysis of the computational complexity. Experimental results on three standard image datasets reveal the advantages that can be achieved with the proposed retrieval scheme.
Kumar, Deepak; Roy, Rene; Kweon, Jin-Hwe; Choi, Jin-ho
2016-06-01
Sub-laminate damage in the form of matrix cracking and delamination was simulated by using interface cohesive elements in the finite element (FE) software ABAQUS. Interface cohesive elements were inserted parallel to the fiber orientation in the transverse ply with equal spacing (matrix cracking) and between the interfaces (delamination). Matrix cracking initiation in the cohesive elements was based on stress traction separation laws and propagated under mixed-mode loading. We expanded the work of Shi et al. (Appl. Compos. Mater. 21, 57-70 2014) to include delamination and simulated additional [45/-45/0/90]s and [02/90n]s { n = 1,2,3} CFRP laminates and a [0/903]s GFRP laminate. Delamination damage was quantified numerically in terms of damage dissipative energy. We observed that transverse matrix cracks can propagate to the ply interface and initiate delamination. We also observed for [0/90n/0] laminates that as the number of 90° ply increases past n = 2, the crack density decreases. The predicted crack density evolution compared well with experimental results and the equivalent constraint model (ECM) theory. Empirical relationships were established between crack density and applied stress by linear curve fitting. The reduction of laminate elastic modulus due to cracking was also computed numerically and it is in accordance with reported experimental measurements.
$B^0_{(s)}$-mixing matrix elements from lattice QCD for the Standard Model and beyond
Bazavov, A; Bouchard, C M; Chang, C C; DeTar, C; Du, Daping; El-Khadra, A X; Freeland, E D; Gamiz, E; Gottlieb, Steven; Heller, U M; Kronfeld, A S; Laiho, J; Mackenzie, P B; Neil, E T; Simone, J; Sugar, R; Toussaint, D; Van de Water, R S; Zhou, Ran
2016-01-01
We calculate---for the first time in three-flavor lattice QCD---the hadronic matrix elements of all five local operators that contribute to neutral $B^0$- and $B_s$-meson mixing in and beyond the Standard Model. We present a complete error budget for each matrix element and also provide the full set of correlations among the matrix elements. We also present the corresponding bag parameters and their correlations, as well as specific combinations of the mixing matrix elements that enter the expression for the neutral $B$-meson width difference. We obtain the most precise determination to date of the SU(3)-breaking ratio $\\xi = 1.203(17)(6)$, where the second error stems from the omission of charm sea quarks, while the first encompasses all other uncertainties. The threefold reduction in total uncertainty tightens the constraint from $B$ mixing on the Cabibbo-Kobayashi-Maskawa (CKM) unitarity triangle. Our calculation employs gauge-field ensembles generated by the MILC Collaboration with four lattice spacings a...
Tornambe, Peter; The ATLAS collaboration
2017-01-01
This proceeding summarizes a search for supersymmetric phenomena in final states with two leptons (electrons or muons) of the same electric charge or three leptons, jets and missing transverse energy. While the same-sign or three leptons signature is present in many SUSY scenarios, SM processes leading to such events have very small cross-sections. Therefore, this analysis benefits from a small SM background in the signal regions leading to a good sensitivity especially in SUSY scenarios with compressed mass spectra or in which the R-parity is not conserved. The search was performed with the full dataset recorded with the ATLAS detector during the year 2015 and 2016 corresponding to a total integrated luminosity of 36.1 fb$^{-1}$. No significant excess above the Standard Model expectations is observed. The results are interpreted in several simplified supersymmetric models featuring R-parity conservation or R-parity violation, extending the exclusion limits from previous searches.
DeCarvalho, N. V.; Chen, B. Y.; Pinho, S. T.; Baiz, P. M.; Ratcliffe, J. G.; Tay, T. E.
2013-01-01
A novel approach is proposed for high-fidelity modeling of progressive damage and failure in composite materials that combines the Floating Node Method (FNM) and the Virtual Crack Closure Technique (VCCT) to represent multiple interacting failure mechanisms in a mesh-independent fashion. In this study, the approach is applied to the modeling of delamination migration in cross-ply tape laminates. Delamination, matrix cracking, and migration are all modeled using fracture mechanics based failure and migration criteria. The methodology proposed shows very good qualitative and quantitative agreement with experiments.
DeCarvalho, Nelson V.; Chen, B. Y.; Pinho, Silvestre T.; Baiz, P. M.; Ratcliffe, James G.; Tay, T. E.
2013-01-01
A novel approach is proposed for high-fidelity modeling of progressive damage and failure in composite materials that combines the Floating Node Method (FNM) and the Virtual Crack Closure Technique (VCCT) to represent multiple interacting failure mechanisms in a mesh-independent fashion. In this study, the approach is applied to the modeling of delamination migration in cross-ply tape laminates. Delamination, matrix cracking, and migration are all modeled using fracture mechanics based failure and migration criteria. The methodology proposed shows very good qualitative and quantitative agreement with experiments.
Effects of Sample Size on Estimates of Population Growth Rates Calculated with Matrix Models
Fiske, Ian J.; Bruna, Emilio M.; Bolker, Benjamin M.
2008-01-01
Background Matrix models are widely used to study the dynamics and demography of populations. An important but overlooked issue is how the number of individuals sampled influences estimates of the population growth rate (λ) calculated with matrix models. Even unbiased estimates of vital rates do not ensure unbiased estimates of λ–Jensen's Inequality implies that even when the estimates of the vital rates are accurate, small sample sizes lead to biased estimates of λ due to increased sampling variance. We investigated if sampling variability and the distribution of sampling effort among size classes lead to biases in estimates of λ. Methodology/Principal Findings Using data from a long-term field study of plant demography, we simulated the effects of sampling variance by drawing vital rates and calculating λ for increasingly larger populations drawn from a total population of 3842 plants. We then compared these estimates of λ with those based on the entire population and calculated the resulting bias. Finally, we conducted a review of the literature to determine the sample sizes typically used when parameterizing matrix models used to study plant demography. Conclusions/Significance We found significant bias at small sample sizes when survival was low (survival = 0.5), and that sampling with a more-realistic inverse J-shaped population structure exacerbated this bias. However our simulations also demonstrate that these biases rapidly become negligible with increasing sample sizes or as survival increases. For many of the sample sizes used in demographic studies, matrix models are probably robust to the biases resulting from sampling variance of vital rates. However, this conclusion may depend on the structure of populations or the distribution of sampling effort in ways that are unexplored. We suggest more intensive sampling of populations when individual survival is low and greater sampling of stages with high elasticities. PMID:18769483
Effects of sample size on estimates of population growth rates calculated with matrix models.
Directory of Open Access Journals (Sweden)
Ian J Fiske
Full Text Available BACKGROUND: Matrix models are widely used to study the dynamics and demography of populations. An important but overlooked issue is how the number of individuals sampled influences estimates of the population growth rate (lambda calculated with matrix models. Even unbiased estimates of vital rates do not ensure unbiased estimates of lambda-Jensen's Inequality implies that even when the estimates of the vital rates are accurate, small sample sizes lead to biased estimates of lambda due to increased sampling variance. We investigated if sampling variability and the distribution of sampling effort among size classes lead to biases in estimates of lambda. METHODOLOGY/PRINCIPAL FINDINGS: Using data from a long-term field study of plant demography, we simulated the effects of sampling variance by drawing vital rates and calculating lambda for increasingly larger populations drawn from a total population of 3842 plants. We then compared these estimates of lambda with those based on the entire population and calculated the resulting bias. Finally, we conducted a review of the literature to determine the sample sizes typically used when parameterizing matrix models used to study plant demography. CONCLUSIONS/SIGNIFICANCE: We found significant bias at small sample sizes when survival was low (survival = 0.5, and that sampling with a more-realistic inverse J-shaped population structure exacerbated this bias. However our simulations also demonstrate that these biases rapidly become negligible with increasing sample sizes or as survival increases. For many of the sample sizes used in demographic studies, matrix models are probably robust to the biases resulting from sampling variance of vital rates. However, this conclusion may depend on the structure of populations or the distribution of sampling effort in ways that are unexplored. We suggest more intensive sampling of populations when individual survival is low and greater sampling of stages with high
Matrix model approximations of fuzzy scalar field theories and their phase diagrams
Energy Technology Data Exchange (ETDEWEB)
Tekel, Juraj [Department of Theoretical Physics, Faculty of Mathematics, Physics and Informatics, Comenius University, Mlynska Dolina, Bratislava, 842 48 (Slovakia)
2015-12-29
We present an analysis of two different approximations to the scalar field theory on the fuzzy sphere, a nonperturbative and a perturbative one, which are both multitrace matrix models. We show that the former reproduces a phase diagram with correct features in a qualitative agreement with the previous numerical studies and that the latter gives a phase diagram with features not expected in the phase diagram of the field theory.
Energy Technology Data Exchange (ETDEWEB)
Ortuno, J E; Kontaxakis, G; Rubio, J L; Santos, A [Departamento de Ingenieria Electronica (DIE), Universidad Politecnica de Madrid, Ciudad Universitaria s/n, 28040 Madrid (Spain); Guerra, P [Networking Research Center on Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), Madrid (Spain)], E-mail: juanen@die.upm.es
2010-04-07
A fully 3D iterative image reconstruction algorithm has been developed for high-resolution PET cameras composed of pixelated scintillator crystal arrays and rotating planar detectors, based on the ordered subsets approach. The associated system matrix is precalculated with Monte Carlo methods that incorporate physical effects not included in analytical models, such as positron range effects and interaction of the incident gammas with the scintillator material. Custom Monte Carlo methodologies have been developed and optimized for modelling of system matrices for fast iterative image reconstruction adapted to specific scanner geometries, without redundant calculations. According to the methodology proposed here, only one-eighth of the voxels within two central transaxial slices need to be modelled in detail. The rest of the system matrix elements can be obtained with the aid of axial symmetries and redundancies, as well as in-plane symmetries within transaxial slices. Sparse matrix techniques for the non-zero system matrix elements are employed, allowing for fast execution of the image reconstruction process. This 3D image reconstruction scheme has been compared in terms of image quality to a 2D fast implementation of the OSEM algorithm combined with Fourier rebinning approaches. This work confirms the superiority of fully 3D OSEM in terms of spatial resolution, contrast recovery and noise reduction as compared to conventional 2D approaches based on rebinning schemes. At the same time it demonstrates that fully 3D methodologies can be efficiently applied to the image reconstruction problem for high-resolution rotational PET cameras by applying accurate pre-calculated system models and taking advantage of the system's symmetries.
Macro-mechanical material model for fiber reinforced metal matrix composites
Banks-Sills, L
1999-01-01
The stress-strain behavior of a metal matrix composite reinforced with unidirectional, continuous and periodic fibers is investigated. Three-dimensional micro-mechanical analyses of a unit cell by means of the finite element method $9 and homogenization-localization are carried out. These calculations allow the determination of material behavior of the in-plane, as well as the fiber directions. The fibers are assumed to be elastic and the matrix elasto-plastic. $9 The matrix material is governed by a von Mises yield surface, isotropic hardening and an associated flow rule. With the aid of these analyses, the foundation to a macro-mechanical material model is presented which is employed to $9 consider an elementary problem. The model includes an anisotropic yield surface with isotropic hardening and an associated flow rule. A beam in bending containing square fibers under plane strain conditions is analyzed by means of $9 the model. Two cases are considered: one in which the fibers are symmetric with respect t...
MATRIX-VBS Condensing Organic Aerosols in an Aerosol Microphysics Model
Gao, Chloe Y.; Tsigaridis, Konstas; Bauer, Susanne E.
2015-01-01
The condensation of organic aerosols is represented in a newly developed box-model scheme, where its effect on the growth and composition of particles are examined. We implemented the volatility-basis set (VBS) framework into the aerosol mixing state resolving microphysical scheme Multiconfiguration Aerosol TRacker of mIXing state (MATRIX). This new scheme is unique and advances the representation of organic aerosols in models in that, contrary to the traditional treatment of organic aerosols as non-volatile in most climate models and in the original version of MATRIX, this new scheme treats them as semi-volatile. Such treatment is important because low-volatility organics contribute significantly to the growth of particles. The new scheme includes several classes of semi-volatile organic compounds from the VBS framework that can partition among aerosol populations in MATRIX, thus representing the growth of particles via condensation of low volatility organic vapors. Results from test cases representing Mexico City and a Finish forrest condistions show good representation of the time evolutions of concentration for VBS species in the gas phase and in the condensed particulate phase. Emitted semi-volatile primary organic aerosols evaporate almost completely in the high volatile range, and they condense more efficiently in the low volatility range.
Modeling of wave propagation in drill strings using vibration transfer matrix methods.
Han, Je-Heon; Kim, Yong-Joe; Karkoub, Mansour
2013-09-01
In order to understand critical vibration of a drill bit such as stick-slip and bit-bounce and their wave propagation characteristics through a drill string system, it is critical to model the torsional, longitudinal, and flexural waves generated by the drill bit vibration. Here, a modeling method based on a vibration transfer matrix between two sets of structural wave variables at the ends of a constant cross-sectional, hollow, circular pipe is proposed. For a drill string system with multiple pipe sections, the total vibration transfer matrix is calculated by multiplying all individual matrices, each is obtained for an individual pipe section. Since drill string systems are typically extremely long, conventional numerical analysis methods such as a finite element method (FEM) require a large number of meshes, which makes it computationally inefficient to analyze these drill string systems numerically. The proposed "analytical" vibration transfer matrix method requires significantly low computational resources. For the validation of the proposed method, experimental and numerical data are obtained from laboratory experiments and FEM analyses conducted by using a commercial FEM package, ANSYS. It is shown that the modeling results obtained by using the proposed method are well matched with the experimental and numerical results.
Zhang, Zhidong
2016-01-01
This study explored an alternative assessment procedure to examine learning trajectories of matrix multiplication. It took rule-based analytical and cognitive task analysis methods specifically to break down operation rules for a given matrix multiplication. Based on the analysis results, a hierarchical Bayesian network, an assessment model,…
Energy Technology Data Exchange (ETDEWEB)
Cardillo, Fabio; Tornambe, Peter [Albert-Ludwigs Universitaet Freiburg (Germany)
2016-07-01
A search for supersymmetric phenomena in final states with two leptons with the same electric charge, jets and missing transverse energy E{sub T}{sup miss} is presented. The production of same-sign lepton pairs or three leptons is only induced by rare Standard Model processes with very small cross-sections. The search thus benefits from little background and has a good exclusion potential in compressed SUSY spectra. This analysis has been performed already in Run-I of the LHC and provided powerful exclusion limits for various SUSY scenarios. In the ongoing Run-II, the search was conducted with the full dataset of pp collisions at √(s)=13 TeV recorded with the ATLAS detector in 2015 corresponding to a total integrated luminosity of 3.3 fb{sup -1}. The sensitivity to a big variety of supersymmetric models is illustrated by the interpretation of the results in the context of four different SUSY benchmark scenarios producing same-sign leptons signatures. The results can be used to set model-independent limits to new physics signals as well as increasing the existing limits on different supersymmetric scenarios with respect to the previous Run-I results. This talk presents the latest results of the same-sign/3L analysis published at the end of 2015. Furthermore, analysis details are addressed, and the prospects for the progressive data-taking during Run-II are shown.
Latré, S.; Desplentere, F.; De Pooter, S.; Seveno, D.
2017-10-01
Nanoscale materials showing superior thermal properties have raised the interest of the building industry. By adding these materials to conventional construction materials, it is possible to decrease the total thermal conductivity by almost one order of magnitude. This conductivity is mainly influenced by the dispersion quality within the matrix material. At the industrial scale, the main challenge is to control this dispersion to reduce or even eliminate thermal bridges. This allows to reach an industrially relevant process to balance out the high material cost and their superior thermal insulation properties. Therefore, a methodology is required to measure and describe these nanoscale distributions within the inorganic matrix material. These distributions are either random or normally distributed through thickness within the matrix material. We show that the influence of these distributions is meaningful and modifies the thermal conductivity of the building material. Hence, this strategy will generate a thermal model allowing to predict the thermal behavior of the nanoscale particles and their distributions. This thermal model will be validated by the hot wire technique. For the moment, a good correlation is found between the numerical results and experimental data for a randomly distributed form of nanoparticles in all directions.
Directory of Open Access Journals (Sweden)
F. A. Mirza
2015-08-01
Full Text Available Lightweighting in the transportation industry is today recognized as one of the most important strategies to improve fuel efficiency and reduce anthropogenic climate-changing, environment-damaging, and human death-causing emissions. However, the structural applications of lightweight alloys are often limited by some inherent deficiencies such as low stiffness, high wear rate and inferior strength. These properties could be effectively enhanced by the addition of stronger and stiffer reinforcements, especially nano-sized particles, into metal matrix to form composites. In most cases three common strengthening mechanisms (load-bearing effect, mismatch of coefficients of thermal expansion, and Orowan strengthening have been considered to predict the yield strength of metal matrix nanocomposites (MMNCs. This study was aimed at developing a unified model by taking into account the matrix grain size and porosity (which is unavoidable in the materials processing such as casting and powder metallurgy in the prediction of the yield strength of MMNCs. The Zener pinning effect of grain boundaries by the nano-sized particles has also been integrated. The model was validated using the experimental data of magnesium- and titanium-based nanocomposites containing different types of nano-sized particles (namely, Al2O3, Y2O3, and carbon nanotubes. The predicted results were observed to be in good agreement with the experimental data reported in the literature.
Exploring Mixed Membership Stochastic Block Models via Non-negative Matrix Factorization
Peng, Chengbin
2014-12-01
Many real-world phenomena can be modeled by networks in which entities and connections are represented by nodes and edges respectively. When certain nodes are highly connected with each other, those nodes forms a cluster, which is called community in our context. It is usually assumed that each node belongs to one community only, but evidences in biology and social networks reveal that the communities often overlap with each other. In other words, one node can probably belong to multiple communities. In light of that, mixed membership stochastic block models (MMB) have been developed to model those networks with overlapping communities. Such a model contains three matrices: two incidence matrices indicating in and out connections and one probability matrix. When the probability of connections for nodes between communities are significantly small, the parameter inference problem to this model can be solved by a constrained non-negative matrix factorization (NMF) algorithm. In this paper, we explore the connection between the two models and propose an algorithm based on NMF to infer the parameters of MMB. The proposed algorithms can detect overlapping communities regardless of knowing or not the number of communities. Experiments show that our algorithm can achieve a better community detection performance than the traditional NMF algorithm. © 2014 IEEE.
Ray, S K; Singh, A K; Kumar, A; Misra, A Mandal S; Mitra, P; Ghosh, N
2016-01-01
We present a simple yet elegant Mueller matrix approach for controlling the Fano interference effect and engineering the resulting asymmetric spectral line shape in anisotropic optical system. The approach is founded on a generalized model of anisotropic Fano resonance, which relates the spectral asymmetry to two physically meaningful and experimentally accessible parameters of interference, namely, the Fano phase shift and the relative amplitudes of the interfering modes. The differences in these parameters between orthogonal linear polarizations in an anisotropic system are exploited to desirably tune the Fano spectral asymmetry using pre- and post-selection of optimized polarization states. Experimental control on the Fano phase and the relative amplitude parameters and resulting tuning of spectral asymmetry is demonstrated in waveguided plasmonic crystals using Mueller matrix-based polarization analysis. The approach enabled tailoring of several exotic regimes of Fano resonance including the complete reve...
Al-NiTi Metal Matrix Composites for Zero CTE Materials: Fabrication, Design, and Modeling
Hehr, Adam; Chen, Xiang; Pritchard, Joshua; Dapino, Marcelo J.; Anderson, Peter M.
Al-NiTi composites fabricated via ultrasonic additive manufacturing (UAM) provide a light-weight solution for low thermal expansion applications. It is shown that the thermal expansion of Al 6061 can be reduced by over 50% by incorporating a 13% volume fraction of NiTi fibers. This reduction in thermal expansion occurs from the contraction of the NiTi fiber during heating, thereby offsetting the thermal expansion of the Al matrix. Al-NiTi composites are made possible by low temperature UAM process. Successful implementation of these composites requires a careful design approach that includes the processing characteristics as well as the thermo-mechanical response of the shape memory fibers and matrix. This is achieved using a NiTi microstructure based FEA model implemented that captures the underlying thermomechanical response of the NiTi fibers and calculates the complex stress state within the composite.
Diffraction Scattering in the Ericson Model for the S-Matrix
Shebeko, A V
2000-01-01
Elastic spinless charge particle scattering on nuclei has been considered by using the strong absorption model put forward by Ericson for the S-matrix in the angular momentum representation. Our analytical method for summation of the partial amplitudes is based upon an extension of the Abel-Plana formula, that enables us to account for contributions from possible singularities of the S-matrix in the right l-halfplane. A uniform asymptotics for the scattering amplitude, derived here, offers a fresh sight at origin of diffractive patterns in the elastic heavy-ion angular distributions. Special attention has been paid to the Coulomb-nuclear interference (particularly, refractive phenomena) for the scattering inside the classically - allowed region (the "illuminated" region) and the classically - forbidden region (the "shadow" region). Unlike the existing analytical results, our solutions of the diffraction problem give no reasons for drawing any deep parallels neither with the Fresnel diffraction in optics nor w...
Wedge-Local Fields in Integrable Models with Bound States II: Diagonal S-Matrix
Cadamuro, Daniela; Tanimoto, Yoh
2017-01-01
We construct candidates for observables in wedge-shaped regions for a class of 1+1-dimensional integrable quantum field theories with bound states whose S-matrix is diagonal, by extending our previous methods for scalar S-matrices. Examples include the Z(N)-Ising models, the A_N-affine Toda field theories and some S-matrices with CDD factors. We show that these candidate operators which are associated with elementary particles commute weakly on a dense domain. For the models with two species of particles, we can take a larger domain of weak commutativity and give an argument for the Reeh-Schlieder property.
Multidisciplinary Product Decomposition and Analysis Based on Design Structure Matrix Modeling
DEFF Research Database (Denmark)
Habib, Tufail
2014-01-01
understanding of the system. Since product architecture has broad implications in relation to product life cycle issues, in this paper, mechatronic product is decomposed into subsystems and components, and then, DSM model is developed to examine the extent of modularity in the system and to manage multiple...... interactions across subsystems and components. For this purpose, Cambridge advanced modeler (CAM) software tool is used to develop the system matrix. The analysis of the product (printer) architecture includes clustering, partitioning as well as structure analysis of the system. The DSM analysis is helpful...
SUSY approach to Pauli Hamiltonians with an axial symmetry
Energy Technology Data Exchange (ETDEWEB)
Ioffe, M V; Kuru, S; Negro, J; Nieto, L M [Departamento de Fisica Teorica, Atomica y Optica, Universidad de Valladolid, 47071 Valladolid (Spain)
2006-06-02
A two-dimensional Pauli Hamiltonian describing the interaction of a neutral spin-1/2 particle with a magnetic field having axial and second-order symmetries is considered. After separation of variables, the one-dimensional matrix Hamiltonian is analysed from the point of view of supersymmetric quantum mechanics. Attention is paid to the discrete symmetries of the Hamiltonian and also to the Hamiltonian hierarchies generated by intertwining operators. The spectrum is studied by means of the associated matrix shape invariance. The relation between the intertwining operators and the second-order symmetries is established, and the full set of ladder operators that complete the dynamical algebra is constructed.
Chehrazi, Ehsan; Sharif, Alireza; Omidkhah, Mohammadreza; Karimi, Mohammad
2017-10-25
Theoretical approaches that accurately predict the gas permeation behavior of nanotube-containing mixed matrix membranes (nanotube-MMMs) are scarce. This is mainly due to ignoring the effects of nanotube/matrix interfacial characteristics in the existing theories. In this paper, based on the analogy of thermal conduction in polymer composites containing nanotubes, we develop a model to describe gas permeation through nanotube-MMMs. Two new parameters, "interfacial thickness" (aint) and "interfacial permeation resistance" (Rint), are introduced to account for the role of nanotube/matrix interfacial interactions in the proposed model. The obtained values of aint, independent of the nature of the permeate gas, increased by increasing both the nanotubes aspect ratio and polymer-nanotube interfacial strength. An excellent correlation between the values of aint and polymer-nanotube interaction parameters, χ, helped to accurately reproduce the existing experimental data from the literature without the need to resort to any adjustable parameter. The data includes 10 sets of CO2/CH4 permeation, 12 sets of CO2/N2 permeation, 3 sets of CO2/O2 permeation, and 2 sets of CO2/H2 permeation through different nanotube-MMMs. Moreover, the average absolute relative errors between the experimental data and the predicted values of the proposed model are very small (less than 5%) in comparison with those of the existing models in the literature. To the best of our knowledge, this is the first study where such a systematic comparison between model predictions and such extensive experimental data is presented. Finally, the new way of assessing gas permeation data presented in the current work would be a simple alternative to complex approaches that are usually utilized to estimate interfacial thickness in polymer composites.
Modeling of outgassing and matrix decomposition in carbon-phenolic composites
Mcmanus, Hugh L.
1993-01-01
A new release rate equation to model the phase change of water to steam in composite materials was derived from the theory of molecular diffusion and equilibrium moisture concentration. The new model is dependent on internal pressure, the microstructure of the voids and channels in the composite materials, and the diffusion properties of the matrix material. Hence, it is more fundamental and accurate than the empirical Arrhenius rate equation currently in use. The model was mathematically formalized and integrated into the thermostructural analysis code CHAR. Parametric studies on variation of several parameters have been done. Comparisons to Arrhenius and straight-line models show that the new model produces physically realistic results under all conditions.
A Computer Modeling of Fracture Based Pull-Out of Nylon 600 Embedded in Cementitious Matrix
Directory of Open Access Journals (Sweden)
Rr. M.I. Retno Susilorini
2009-01-01
Full Text Available This paper reports the development of a computer model that represents a pull-out process of nylon 600 embedded in cementitious matrix. The model is based on fracture approach considering the Poisson’s effect and stable crack length. To back up the model four pull out tests of nylon 600 fiber, diameter 1.1 mm, with two fiber embedment lengths, 100 mm and 120 mm are done. The numerical approach is then compared to the experimental results. The computer model is built on Delphi 7 and named “Program Cabut-Serat Fraktur". This study shows that the computer model could represent the fracture phenomenon during the pull-out process.
Pollutant Dispersion Modeling in Natural Streams Using the Transmission Line Matrix Method
Directory of Open Access Journals (Sweden)
Safia Meddah
2015-09-01
Full Text Available Numerical modeling has become an indispensable tool for solving various physical problems. In this context, we present a model of pollutant dispersion in natural streams for the far field case where dispersion is considered longitudinal and one-dimensional in the flow direction. The Transmission Line Matrix (TLM, which has earned a reputation as powerful and efficient numerical method, is used. The presented one-dimensional TLM model requires a minimum input data and provides a significant gain in computing time. To validate our model, the results are compared with observations and experimental data from the river Severn (UK. The results show a good agreement with experimental data. The model can be used to predict the spatiotemporal evolution of a pollutant in natural streams for effective and rapid decision-making in a case of emergency, such as accidental discharges in a stream with a dynamic similar to that of the river Severn (UK.
A dynamic model of mobile concrete pump boom based on discrete time transfer matrix method
Ren, Wu; Wu, Yunxin; Zhang, Zhaowei
2013-12-01
Mobile concrete pump boom is typical multibody large-scale motion manipulator. Due to posture constantly change in working process, kinematic rule and dynamic characteristic are difficult to solve. A dynamics model of a mobile concrete pump boom is established based on discrete time transfer matrix method (DTTMM). The boom system is divided into sub-structure A and substructure B. Sub-structure A is composed by the 1st boom and hydraulic actuator as well as the support. And substructure B is consists of the other three booms and corresponding hydraulic actuators. In the model, the booms and links are regarded as rigid elements and the hydraulic cylinders are equivalent to spring-damper. The booms are driven by the controllable hydraulic actuators. The overall dynamic equation and transfer matrix of the model can be assembled by sub-structures A and B. To get a precise result, step size and integration parameters are studied then. Next the tip displacement is calculated and compared with the result of ADAMS software. The displacement and rotation angle curves of the proposed method fit well with the ADAMS model. Besides it is convenient in modeling and saves time. So it is suitable for mobile concrete pump boom real-time monitoring and dynamic analysis. All of these provide reference to boom optimize and engineering application of such mechanisms.
Evaluation of Solid Modeling Software for Finite Element Analysis of Woven Ceramic Matrix Composites
Nemeth, Noel N.; Mital, Subodh; Lang, Jerry
2010-01-01
Three computer programs, used for the purpose of generating 3-D finite element models of the Repeating Unit Cell (RUC) of a textile, were examined for suitability to model woven Ceramic Matrix Composites (CMCs). The programs evaluated were the open-source available TexGen, the commercially available WiseTex, and the proprietary Composite Material Evaluator (COMATE). A five-harness-satin (5HS) weave for a melt-infiltrated (MI) silicon carbide matrix and silicon carbide fiber was selected as an example problem and the programs were tested for their ability to generate a finite element model of the RUC. The programs were also evaluated for ease-of-use and capability, particularly for the capability to introduce various defect types such as porosity, ply shifting, and nesting of a laminate. Overall, it was found that TexGen and WiseTex were useful for generating solid models of the tow geometry; however, there was a lack of consistency in generating well-conditioned finite element meshes of the tows and matrix. TexGen and WiseTex were both capable of allowing collective and individual shifting of tows within a ply and WiseTex also had a ply nesting capability. TexGen and WiseTex were sufficiently userfriendly and both included a Graphical User Interface (GUI). COMATE was satisfactory in generating a 5HS finite element mesh of an idealized weave geometry but COMATE lacked a GUI and was limited to only 5HS and 8HS weaves compared to the larger amount of weave selections available with TexGen and WiseTex.
A semi-analytical method for simulating matrix diffusion in numerical transport models.
Falta, Ronald W; Wang, Wenwen
2017-02-01
A semi-analytical approximation for transient matrix diffusion is developed for use in numerical contaminant transport simulators. This method is an adaptation and extension of the heat conduction method of Vinsome and Westerveld (1980) used to simulate heat losses during thermally enhanced oil recovery. The semi-analytical method is used in place of discretization of the low permeability materials, and it represents the concentration profile in the low permeability materials with a fitting function that is adjusted in each element at each time-step. The resulting matrix diffusion fluxes are added to the numerical model as linear concentration-dependent source/sink terms. Since only the high permeability zones need to be discretized, the numerical formulation is extremely efficient compared to traditional approaches that require discretization of both the high and low permeability zones. The semi-analytical method compares favorably with the analytical solution for transient one-dimensional diffusion with first order decay, with a two-layer aquifer/aquitard solution, with the solution for transport in a fracture with matrix diffusion and decay, and with a fully numerical solution for transport in a thin sand zone bounded by clay with variable decay rates. Copyright © 2017 Elsevier B.V. All rights reserved.
Enamel matrix derivative for replanted teeth in animal models: a systematic review and meta-analysis
Directory of Open Access Journals (Sweden)
Sahng G. Kim
2013-11-01
Full Text Available Objectives To investigate the effect of enamel matrix derivative (EMD on periodontal healing of replanted teeth in animal models. Materials and Methods The authors searched MEDLINE, PubMed, EMBASE, Cochrane Library, Web of Knowledge and Scopus for articles published up to Oct 2012. Animal studies in which EMD was applied in transplanted or replanted teeth with adequate controls and histological data were considered. Normal periodontal healing or root resorption determined by histology after EMD was applied in replanted teeth with adequate controls was used as outcome measures. The following search strategy was used: ('Emdogain' OR 'enamel matrix proteins' OR 'enamel matrix derivative' AND ('avulsion' OR 'transplantion' OR 'autotransplantation' OR 'replantation'. Results Six animal studies were included in the final review. There was great heterogeneity in study design among included studies. Two studies with similar study designs were identified and analyzed by a meta-analysis. The pooled estimates showed a significantly higher normal healing and surface resorption and significantly less inflammatory and replacement resorption in EMD-treated groups compared with non-EMD-treated groups. Conclusions With the limitations of this systematic review, the use of EMD led to greater normal periodontal healing and surface root resorption and less inflammatory and replacement root resorption in the presence of periodontal ligaments. However, no definite conclusion could be drawn with regard to the effect of EMD on periodontal healing and root resorption when no periodontal ligaments exist.
Modelling thermomechanical conditions at the tool/matrix interface in Friction Stir Welding
DEFF Research Database (Denmark)
Schmidt, Henrik Nikolaj Blich; Hattel, Jesper
2004-01-01
In friction stir welding the material flow is among others controlled by the contact condition at the tool interface, the thermomechanical state of the matrix and the welding parameters. The conditions under which the deposition process is successful are not fully understood and in most models pr......) as in the experiment and ii) simulating an offset in plunge depth. Both simulations reach similar steady state solutions. The model results are compared to the plunge force and heat generation observed in experimental welds in AA2024-T3.......In friction stir welding the material flow is among others controlled by the contact condition at the tool interface, the thermomechanical state of the matrix and the welding parameters. The conditions under which the deposition process is successful are not fully understood and in most models...... presented previously in literature, the modelling of the material flow at the tool interface has been prescribed as boundary conditions, i.e. the material is forced to keep contact with the tool. The objective of the present work is to analyse the thermomechanical conditions under which a consolidated weld...
Energy Technology Data Exchange (ETDEWEB)
Telfeyan, Katherine Christina [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Ware, Stuart Douglas [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Reimus, Paul William [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Birdsell, Kay Hanson [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
2017-11-06
Diffusion cell and diffusion wafer experiments were conducted to compare methods for estimating matrix diffusion coefficients in rock core samples from Pahute Mesa at the Nevada Nuclear Security Site (NNSS). A diffusion wafer method, in which a solute diffuses out of a rock matrix that is pre-saturated with water containing the solute, is presented as a simpler alternative to the traditional through-diffusion (diffusion cell) method. Both methods yielded estimates of matrix diffusion coefficients that were within the range of values previously reported for NNSS volcanic rocks. The difference between the estimates of the two methods ranged from 14 to 30%, and there was no systematic high or low bias of one method relative to the other. From a transport modeling perspective, these differences are relatively minor when one considers that other variables (e.g., fracture apertures, fracture spacings) influence matrix diffusion to a greater degree and tend to have greater uncertainty than diffusion coefficients. For the same relative random errors in concentration measurements, the diffusion cell method yields diffusion coefficient estimates that have less uncertainty than the wafer method. However, the wafer method is easier and less costly to implement and yields estimates more quickly, thus allowing a greater number of samples to be analyzed for the same cost and time. Given the relatively good agreement between the methods, and the lack of any apparent bias between the methods, the diffusion wafer method appears to offer advantages over the diffusion cell method if better statistical representation of a given set of rock samples is desired.
Modelling Strategies for Simulating Delamination and Matrix Cracking in Composite Laminates
Lachaud, Frederic; Espinosa, Christine; Michel, Laurent; Rahme, Pierre; Piquet, Robert
2015-08-01
The composite materials are nowadays widely used in aeronautical domain. These materials are subjected to different types of loading that can damage a part of the structure. This diminishes the resistance of the structure to failure. In this paper, matrix cracking and delamination propagation in composite laminates are simulated as a part of damage. Two different computational strategies are developed: (i) a cohesive model (CM) based on the classical continuum mechanics and (ii) a continuous damage material model (CDM) coupling failure modes and damage. Another mixed methodology (MM) is proposed using the continuous damage model for delamination initiation and the cohesive model for 3D crack propagation and mesh openings. A good agreement was obtained when compared simple characterization tests and corresponding simulations.
Double beta decay nuclear matrix elements in extended shell model spaces
Horoi, Mihai
2017-09-01
In a recent publication we concluded that the shell model double beta decay nuclear matrix elements may be affected to certain degrees by the lack of pairing correlations with orbitals outside the typical shell model spaces. Here we report results of calculations for 48Ca that includes 21 spherical orbitals for both protons and neutrons. We are using a realistic Hamiltonian inside the fp model space, thus maintaining a good description of the nuclear structure properties of the nuclei of interest. We are only allowing pairing interactions between the fp orbitals and the remaining 17 orbitals, and up to two particle excitations in and out of the fp model space. This approach could be also extended to the case of 82Se. Support from U.S. NSF Grant PHY-1404442 and DOE Grants DE-SC0008529 and DE-SC0015376 is acknowledged.
Cramer, Nick; Swei, Sean Shan-Min; Cheung, Kenny; Teodorescu, Mircea
2015-01-01
This paper presents a modeling and control of aerostructure developed by lattice-based cellular materials/components. The proposed aerostructure concept leverages a building block strategy for lattice-based components which provide great adaptability to varying ight scenarios, the needs of which are essential for in- ight wing shaping control. A decentralized structural control design is proposed that utilizes discrete-time lumped mass transfer matrix method (DT-LM-TMM). The objective is to develop an e ective reduced order model through DT-LM-TMM that can be used to design a decentralized controller for the structural control of a wing. The proposed approach developed in this paper shows that, as far as the performance of overall structural system is concerned, the reduced order model can be as e ective as the full order model in designing an optimal stabilizing controller.
Noncommutative geometry and the BV formalism: Application to a matrix model
Iseppi, Roberta A.; van Suijlekom, Walter D.
2017-10-01
We analyze a U(2) -matrix model derived from a finite spectral triple. By applying the BV formalism, we find a general solution to the classical master equation. To describe the BV formalism in the context of noncommutative geometry, we define two finite spectral triples: the BV spectral triple and the BV auxiliary spectral triple. These are constructed from the gauge fields, ghost fields and anti-fields that enter the BV construction. We show that their fermionic actions add up precisely to the BV action. This approach allows for a geometric description of the ghost fields and their properties in terms of the BV spectral triple.
Phases and geometry of the N=1 A_2 quiver gauge theory and matrix models
Casero, Roberto; Trincherini, Enrico
2003-01-01
We study the phases and geometry of the N=1 A_2 quiver gauge theory using matrix models and a generalized Konishi anomaly. We consider the theory both in the Coulomb and Higgs phases. Solving the anomaly equations, we find that a meromorphic one-form sigma(z)dz is naturally defined on the curve Sigma associated to the theory. Using the Dijkgraaf-Vafa conjecture, we evaluate the effective low-energy superpotential and demonstrate that its equations of motion can be translated into a geometric ...
Random matrix theory and higher genus integrability: the quantum chiral Potts model
Energy Technology Data Exchange (ETDEWEB)
Angles d' Auriac, J.Ch. [Centre de Recherches sur les Tres Basses Temperatures, BP 166, Grenoble (France)]. E-mail: dauriac@polycnrs-gre.fr; Maillard, J.M.; Viallet, C.M. [LPTHE, Tour 16, Paris (France)]. E-mails: maillard@lpthe.jussieu.fr; viallet@lpthe.jussieu.fr
2002-06-14
We perform a random matrix theory (RMT) analysis of the quantum four-state chiral Potts chain for different sizes of the chain up to size L 8. Our analysis gives clear evidence of a Gaussian orthogonal ensemble (GOE) statistics, suggesting the existence of a generalized time-reversal invariance. Furthermore, a change from the (generic) GOE distribution to a Poisson distribution occurs when the integrability conditions are met. The chiral Potts model is known to correspond to a (star-triangle) integrability associated with curves of genus higher than zero or one. Therefore, the RMT analysis can also be seen as a detector of 'higher genus integrability'. (author)
M2-brane dynamics in the classical limit of the BMN matrix model
Directory of Open Access Journals (Sweden)
Minos Axenides
2017-10-01
Full Text Available We investigate the large-N limit of the BMN matrix model by analyzing the dynamics of ellipsoidal M2-branes that spin in the 11-dimensional maximally supersymmetric SO(3×SO(6 plane-wave background. We identify finite-energy solutions by specifying the local minima of the corresponding energy functional. These configurations are static in SO(3 due to the Myers effect and rotate in SO(6 with an angular momentum that is bounded from above. As a first step towards studying their chaotic properties, we evaluate the Lyapunov exponents of their radial fluctuations.
Density induced phase transitions in the Schwinger model. A study with matrix product states
Energy Technology Data Exchange (ETDEWEB)
Banuls, Mari Carmen; Cirac, J. Ignacio; Kuehn, Stefan [Max-Planck-Institut fuer Quantenoptik (MPQ), Garching (Germany); Cichy, Krzysztof [Frankfurt Univ. (Germany). Inst. fuer Theoretische Physik; Adam Mickiewicz Univ., Poznan (Poland). Faculty of Physics; Jansen, Karl [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany). John von Neumann-Inst. fuer Computing NIC
2017-02-15
We numerically study the zero temperature phase structure of the multiflavor Schwinger model at nonzero chemical potential. Using matrix product states, we reproduce analytical results for the phase structure for two flavors in the massless case and extend the computation to the massive case, where no analytical predictions are available. Our calculations allow us to locate phase transitions in the mass-chemical potential plane with great precision and provide a concrete example of tensor networks overcoming the sign problem in a lattice gauge theory calculation.
The mass spectrum of the Schwinger model with matrix product states
Energy Technology Data Exchange (ETDEWEB)
Banuls, M.C.; Cirac, J.I. [Max-Planck-Institut fuer Quantenoptik (MPQ), Garching (Germany); Cichy, K. [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany); Poznan Univ. (Poland). Faculty of Physics; Jansen, K. [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany); Cyprus Univ., Nicosia (Cyprus). Dept. of Physics
2013-07-15
We show the feasibility of tensor network solutions for lattice gauge theories in Hamiltonian formulation by applying matrix product states algorithms to the Schwinger model with zero and non-vanishing fermion mass. We introduce new techniques to compute excitations in a system with open boundary conditions, and to identify the states corresponding to low momentum and different quantum numbers in the continuum. For the ground state and both the vector and scalar mass gaps in the massive case, the MPS technique attains precisions comparable to the best results available from other techniques.
DarkSUSY 6 : An Advanced Tool to Compute Dark Matter Properties Numerically
Bringmann, Torsten; Edsjo, Joakim; Gondolo, Paolo; Ullio, Piero; Bergstrom, Lars
2018-01-01
The nature of dark matter remains one of the key science questions. Weakly Interacting Massive Particles (WIMPs) are among the best motivated particle physics candidates, allowing to explain the measured dark matter density by employing standard big-bang thermodynamics. Examples include the lightest supersymmetric particle, though many alternative particles have been suggested as a solution to the dark matter puzzle. We introduce here a radically new version of the widely used DarkSUSY packag...
Determination of QCD Backgrounds in ATLAS: A challenge for SUSY searches
Meirose, B; The ATLAS collaboration
2009-01-01
The understanding of QCD jet events in supersymmetry is one of the biggest background-determination challenges in SUSY searches. Effects such as dead material and pile-up of machine backgrounds can significantly affect the missing transverse energy. Other effects like jet punch through and cosmic ray backgrounds can also be important background sources. We discuss several QCD background sources and techniques under development in ATLAS to remove or estimate them.
Predictions for Higgs and SUSY spectra from SO(10) Yukawa Unification with $\\mu > 0$
Blazek, T; Raby, S; CERN. Geneva
2002-01-01
We use t, b, tau Yukawa unification to constrain SUSY parameter space. We find a narrow region survives for mu > 0 (suggested by b --> s gamma and the anomalous magnetic moment of the muon) with A_0 \\sim - 1.9 m_{16}, m_{10} \\sim 1.4 m_{16}, m_{16} \\sim 1200 -3000 GeV and mu, M_{1/2} \\sim 100 - 500 GeV. Demanding Yukawa unification thus makes definite predictions for Higgs and sparticle masses.
A matrix transition model for an uneven-aged, oak-hickory forest in the Missouri ozark highlands
James R. Lootens; David R. Larsen; Edward F. Loewenstein
1999-01-01
We presented a matrix growth model for an uneven-aged, oak-hickory forest in the Ozark Highlands of Missouri. The model was developed to predict ingrowth, growth of surviving trees, and mortality by diameter class for a five-year period. Tree removal from management activities is accounted for in the model. We evaluated a progression of models from a static, fixed...
Micromechanics Fatigue Damage Analysis Modeling for Fabric Reinforced Ceramic Matrix Composites
Min, J. B.; Xue, D.; Shi, Y.
2013-01-01
A micromechanics analysis modeling method was developed to analyze the damage progression and fatigue failure of fabric reinforced composite structures, especially for the brittle ceramic matrix material composites. A repeating unit cell concept of fabric reinforced composites was used to represent the global composite structure. The thermal and mechanical properties of the repeating unit cell were considered as the same as those of the global composite structure. The three-phase micromechanics, the shear-lag, and the continuum fracture mechanics models were integrated with a statistical model in the repeating unit cell to predict the progressive damages and fatigue life of the composite structures. The global structure failure was defined as the loss of loading capability of the repeating unit cell, which depends on the stiffness reduction due to material slice failures and nonlinear material properties in the repeating unit cell. The present methodology is demonstrated with the analysis results evaluated through the experimental test performed with carbon fiber reinforced silicon carbide matrix plain weave composite specimens.
Supersymmetric models on magnetized orbifolds with flux-induced Fayet-Iliopoulos terms
Abe, Hiroyuki; Kobayashi, Tatsuo; Sumita, Keigo; Tatsuta, Yoshiyuki
2017-01-01
We study supersymmetric (SUSY) models derived from the ten-dimensional SUSY Yang-Mills theory compactified on magnetized orbifolds, with nonvanishing Fayet-Iliopoulos (FI) terms induced by magnetic fluxes in extra dimensions. Allowing the presence of FI-terms relaxes a constraint on flux configurations in SUSY model building based on magnetized backgrounds. In this case, charged fields develop their vacuum expectation values to cancel the FI-terms in the D-flat directions of fluxed gauge symmetries, which break the gauge symmetries and lead to a SUSY vacuum. Based on this idea, we propose a new class of SUSY magnetized orbifold models with three generations of quarks and leptons. Especially, we construct a model where the right-handed sneutrinos develop their vacuum expectation values which restore the supersymmetry but yield lepton number violating terms below the compactification scale, and show their phenomenological consequences.
Besjes, Geert Jan; Caron, Sascha
In this thesis, a search for new elementary particles predicted by a theory called supersymmetry (SUSY), which attempts to address shortcomings in our current description of particle physics, the Standard Model, is presented. No events incompatible with the Standard Model are observed, however. The results obtained in this search are also used in fits to a larger supersymmetric model, and combined with different analyses to obtain improved limits on simplified models. In addition, prospects for a similar search at the proposed high-luminosity LHC are discussed. Finally, HistFitter is presented, a program developed to perform searches in high-energy physics. Supersymmetry is searched for in a decay channel with 2 to 6 jets, missing energy, and no leptons in the final state. The coupling of squarks and gluinos to the strong force leads to a final state with many jets, in which the lightest supersymmetric particle produced in the cascade decay escapes the detector unseen. The analysis is designed using 15 signa...
Ability of matrix models to explain the past and predict the future of plant populations.
Crone, Elizabeth E; Ellis, Martha M; Morris, William F; Stanley, Amanda; Bell, Timothy; Bierzychudek, Paulette; Ehrlén, Johan; Kaye, Thomas N; Knight, Tiffany M; Lesica, Peter; Oostermeijer, Gerard; Quintana-Ascencio, Pedro F; Ticktin, Tamara; Valverde, Teresa; Williams, Jennifer L; Doak, Daniel F; Ganesan, Rengaian; McEachern, Kathyrn; Thorpe, Andrea S; Menges, Eric S
2013-10-01
Uncertainty associated with ecological forecasts has long been recognized, but forecast accuracy is rarely quantified. We evaluated how well data on 82 populations of 20 species of plants spanning 3 continents explained and predicted plant population dynamics. We parameterized stage-based matrix models with demographic data from individually marked plants and determined how well these models forecast population sizes observed at least 5 years into the future. Simple demographic models forecasted population dynamics poorly; only 40% of observed population sizes fell within our forecasts' 95% confidence limits. However, these models explained population dynamics during the years in which data were collected; observed changes in population size during the data-collection period were strongly positively correlated with population growth rate. Thus, these models are at least a sound way to quantify population status. Poor forecasts were not associated with the number of individual plants or years of data. We tested whether vital rates were density dependent and found both positive and negative density dependence. However, density dependence was not associated with forecast error. Forecast error was significantly associated with environmental differences between the data collection and forecast periods. To forecast population fates, more detailed models, such as those that project how environments are likely to change and how these changes will affect population dynamics, may be needed. Such detailed models are not always feasible. Thus, it may be wiser to make risk-averse decisions than to expect precise forecasts from models. © 2013 Society for Conservation Biology.
Carbon isotope composition of ambient CO2 and recycling: a matrix simulation model
da Silveira Lobo Sternberg, Leonel; DeAngelis, Donald L.
2002-01-01
The relationship between isotopic composition and concentration of ambient CO2 in a canopy and its associated convective boundary layer was modeled. The model divides the canopy and convective boundary layer into several layers. Photosynthesis, respiration, and exchange between each layer can be simulated by matrix equations. This simulation can be used to calculate recycling; defined here as the amount of respired CO2 re-fixed by photosynthesis relative to the total amount of respired CO2. At steady state the matrix equations can be solved for the canopy and convective boundary layer CO2 concentration and isotopic profile, which can be used to calculate a theoretical recycling index according to a previously developed equation. There is complete agreement between simulated and theoretical recycling indices for different exchange scenarios. Recycling indices from a simulation of gas exchange between a heterogeneous vegetation canopy and the troposphere also agreed with a more generalized form of the theoretical recycling equation developed here.
A modelling of AC voltage stabilizer based on a hybrid transformer with matrix converter
Directory of Open Access Journals (Sweden)
Szcześniak Paweł
2017-06-01
Full Text Available This article presents a study of an AC voltage stabilizer based on a three-phase hybrid transformer combined with a matrix converter. The proposed solution is used to control AC voltage amplitude and phase shift. By adjustment of these voltage parameters we can reduce the effects of overvoltage, voltage dips or lamp flicker. Such negative phenomena are very significant, particularly from the perspective of the final consumer and sensitive loads connected to the power network. Often the voltage in the power system can be adjusted using a mechanical or thyristor controlled regulator, which in a stepwise manner switches the taps of the electromagnetic transformer. The method for obtaining continuous control of the voltage magnitude and phase shift with the use of a conventional transformer with two output windings and a matrix converter is presented in this paper. The operating principles, mathematical model and properties of the proposed voltage stabilizers are discussed in this paper. The main part of the article will be devoted to the mathematical model which is based on an averaged equation. Computer simulation results are presented and compared with the results of a mathematical study.
Modeling of the viscoelastic behavior of a polyimide matrix at elevated temperature
Crochon, Thibaut
Use of Polymer Matrix Composite Materials (PMCMs) in aircraft engines requires materials able to withstand extreme service conditions, such as elevated temperatures, high mechanical loadings and an oxidative environment. In such an environment, the polymer matrix is likely to exhibit a viscoelastic behavior dependent on the mechanical loading and temperature. In addition, the combined effects of elevated temperature and the environment near the engines are likely to increase physical as well as chemical aging. These various parameters need to be taken into consideration for the designer to be able to predict the material behavior over the service life of the components. The main objective of this thesis was to study the viscoelastic behavior of a high temperature polyimide matrix and develop a constitutive theory able to predict the material behavior for every of service condition. Then, the model had to have to be implemented into commercially available finite-element software such as ABAQUS or ANSYS. Firstly, chemical aging of the material at service temperature was studied. To that end, a thermogravimetric analysis of the matrix was conducted on powder samples in air atmosphere. Two kinds of tests were performed: i) kinetic tests in which powder samples were heated at a constant rate until complete sublimation; ii) isothermal tests in which the samples were maintained at a constant temperature for 24 hours. The first tests were used to develop a degradation model, leading to an excellent fit of the experimental data. Then, the model was used to predict the isothermal data but which much less success, particularly for the lowest temperatures. At those temperatures, the chemical degradation was preceded by an oxidation phase which the model was not designed to predict. Other isothermal degradation tests were also performed on tensile tests samples instead of powders. Those tests were conducted at service temperature for a much longer period of time. The samples
Robust linear equation dwell time model compatible with large scale discrete surface error matrix.
Dong, Zhichao; Cheng, Haobo; Tam, Hon-Yuen
2015-04-01
The linear equation dwell time model can translate the 2D convolution process of material removal during subaperture polishing into a more intuitional expression, and may provide relatively fast and reliable results. However, the accurate solution of this ill-posed equation is not so easy, and its practicability for a large scale surface error matrix is still limited. This study first solves this ill-posed equation by Tikhonov regularization and the least square QR decomposition (LSQR) method, and automatically determines an optional interval and a typical value for the damped factor of regularization, which are dependent on the peak removal rate of tool influence functions. Then, a constrained LSQR method is presented to increase the robustness of the damped factor, which can provide more consistent dwell time maps than traditional LSQR. Finally, a matrix segmentation and stitching method is used to cope with large scale surface error matrices. Using these proposed methods, the linear equation model becomes more reliable and efficient in practical engineering.
Development of a 3D matrix for modeling mammalian spinal cord injury in vitro
Directory of Open Access Journals (Sweden)
Juan Felipe Diaz Quiroz
2016-01-01
Full Text Available Spinal cord injury affects millions of people around the world, however, limited therapies are available to improve the quality of life of these patients. Spinal cord injury is usually modeled in rats and mice using contusion or complete transection models and this has led to a deeper understanding of the molecular and cellular complexities of the injury. However, it has not to date led to development of successful novel therapies, this is in part due to the complexity of the injury and the difficulty of deciphering the exact roles and interactions of different cells within this complex environment. Here we developed a collagen matrix that can be molded into the 3D tubular shape with a lumen and can hence support cell interactions in a similar architecture to a spinal cord. We show that astrocytes can be successfully grown on this matrix in vitro and when injured, the cells respond as they do in vivo and undergo reactive gliosis, one of the steps that lead to formation of a glial scar, the main barrier to spinal cord regeneration. In the future, this system can be used to quickly assess the effect of drugs on glial scar protein activity or to perform live imaging of labeled cells after exposure to drugs.
DEFF Research Database (Denmark)
Chambon, Julie Claire Claudia; Broholm, Mette Martina; Binning, Philip John
2010-01-01
Clayey tills contaminated with chlorinated solvents are a threat to groundwater and are difficult to remediate. A numerical model is developed for assessing leaching processes and for simulating the remediation via enhanced anaerobic dechlorination. The model simulates the transport...... of a contaminant in a single fracture-clay matrix system coupled with a reactive model for anaerobic dechlorination. The model takes into account microbially driven anaerobic dechlorination, where sequential Monod kinetics with competitive inhibition is used to model the reaction rates, and degradation...... is localized to account for potential pore size limitations on microbial entry to the clay matrix. The model is used to assess the distribution of TCE and its daughter products in the clay matrix and the concentration of the different compounds at the outlet of the fracture. The time frame for complete cleanup...
SUSI 62 A Robust and Safe Parachute Uav with Long Flight Time and Good Payload
Thamm, H. P.
2011-09-01
In many research areas in the geo-sciences (erosion, land use, land cover change, etc.) or applications (e.g. forest management, mining, land management etc.) there is a demand for remote sensing images of a very high spatial and temporal resolution. Due to the high costs of classic aerial photo campaigns, the use of a UAV is a promising option for obtaining the desired remote sensed information at the time it is needed. However, the UAV must be easy to operate, safe, robust and should have a high payload and long flight time. For that purpose, the parachute UAV SUSI 62 was developed. It consists of a steel frame with a powerful 62 cm3 2- stroke engine and a parachute wing. The frame can be easily disassembled for transportation or to replace parts. On the frame there is a gimbal mounted sensor carrier where different sensors, standard SLR cameras and/or multi-spectral and thermal sensors can be mounted. Due to the design of the parachute, the SUSI 62 is very easy to control. Two different parachute sizes are available for different wind speed conditions. The SUSI 62 has a payload of up to 8 kg providing options to use different sensors at the same time or to extend flight duration. The SUSI 62 needs a runway of between 10 m and 50 m, depending on the wind conditions. The maximum flight speed is approximately 50 km/h. It can be operated in a wind speed of up to 6 m/s. The design of the system utilising a parachute UAV makes it comparatively safe as a failure of the electronics or the remote control only results in the UAV coming to the ground at a slow speed. The video signal from the camera, the GPS coordinates and other flight parameters are transmitted to the ground station in real time. An autopilot is available, which guarantees that the area of investigation is covered at the desired resolution and overlap. The robustly designed SUSI 62 has been used successfully in Europe, Africa and Australia for scientific projects and also for agricultural, forestry and
SUSI 62 A ROBUST AND SAFE PARACHUTE UAV WITH LONG FLIGHT TIME AND GOOD PAYLOAD
Directory of Open Access Journals (Sweden)
H. P. Thamm
2012-09-01
Full Text Available In many research areas in the geo-sciences (erosion, land use, land cover change, etc. or applications (e.g. forest management, mining, land management etc. there is a demand for remote sensing images of a very high spatial and temporal resolution. Due to the high costs of classic aerial photo campaigns, the use of a UAV is a promising option for obtaining the desired remote sensed information at the time it is needed. However, the UAV must be easy to operate, safe, robust and should have a high payload and long flight time. For that purpose, the parachute UAV SUSI 62 was developed. It consists of a steel frame with a powerful 62 cm3 2- stroke engine and a parachute wing. The frame can be easily disassembled for transportation or to replace parts. On the frame there is a gimbal mounted sensor carrier where different sensors, standard SLR cameras and/or multi-spectral and thermal sensors can be mounted. Due to the design of the parachute, the SUSI 62 is very easy to control. Two different parachute sizes are available for different wind speed conditions. The SUSI 62 has a payload of up to 8 kg providing options to use different sensors at the same time or to extend flight duration. The SUSI 62 needs a runway of between 10 m and 50 m, depending on the wind conditions. The maximum flight speed is approximately 50 km/h. It can be operated in a wind speed of up to 6 m/s. The design of the system utilising a parachute UAV makes it comparatively safe as a failure of the electronics or the remote control only results in the UAV coming to the ground at a slow speed. The video signal from the camera, the GPS coordinates and other flight parameters are transmitted to the ground station in real time. An autopilot is available, which guarantees that the area of investigation is covered at the desired resolution and overlap. The robustly designed SUSI 62 has been used successfully in Europe, Africa and Australia for scientific projects and also for
Matrix product state calculations for one-dimensional quantum chains and quantum impurity models
Energy Technology Data Exchange (ETDEWEB)
Muender, Wolfgang
2011-09-28
This thesis contributes to the field of strongly correlated electron systems with studies in two distinct fields thereof: the specific nature of correlations between electrons in one dimension and quantum quenches in quantum impurity problems. In general, strongly correlated systems are characterized in that their physical behaviour needs to be described in terms of a many-body description, i.e. interactions correlate all particles in a complex way. The challenge is that the Hilbert space in a many-body theory is exponentially large in the number of particles. Thus, when no analytic solution is available - which is typically the case - it is necessary to find a way to somehow circumvent the problem of such huge Hilbert spaces. Therefore, the connection between the two studies comes from our numerical treatment: they are tackled by the density matrix renormalization group (DMRG) and the numerical renormalization group (NRG), respectively, both based on matrix product states. The first project presented in this thesis addresses the problem of numerically finding the dominant correlations in quantum lattice models in an unbiased way, i.e. without using prior knowledge of the model at hand. A useful concept for this task is the correlation density matrix (CDM) which contains all correlations between two clusters of lattice sites. We show how to extract from the CDM, a survey of the relative strengths of the system's correlations in different symmetry sectors as well as detailed information on the operators carrying long-range correlations and the spatial dependence of their correlation functions. We demonstrate this by a DMRG study of a one-dimensional spinless extended Hubbard model, while emphasizing that the proposed analysis of the CDM is not restricted to one dimension. The second project presented in this thesis is motivated by two phenomena under ongoing experimental and theoretical investigation in the context of quantum impurity models: optical absorption
UTOPIAN: user-driven topic modeling based on interactive nonnegative matrix factorization.
Choo, Jaegul; Lee, Changhyun; Reddy, Chandan K; Park, Haesun
2013-12-01
Topic modeling has been widely used for analyzing text document collections. Recently, there have been significant advancements in various topic modeling techniques, particularly in the form of probabilistic graphical modeling. State-of-the-art techniques such as Latent Dirichlet Allocation (LDA) have been successfully applied in visual text analytics. However, most of the widely-used methods based on probabilistic modeling have drawbacks in terms of consistency from multiple runs and empirical convergence. Furthermore, due to the complicatedness in the formulation and the algorithm, LDA cannot easily incorporate various types of user feedback. To tackle this problem, we propose a reliable and flexible visual analytics system for topic modeling called UTOPIAN (User-driven Topic modeling based on Interactive Nonnegative Matrix Factorization). Centered around its semi-supervised formulation, UTOPIAN enables users to interact with the topic modeling method and steer the result in a user-driven manner. We demonstrate the capability of UTOPIAN via several usage scenarios with real-world document corpuses such as InfoVis/VAST paper data set and product review data sets.
Thermal evolution of the one-flavour Schwinger model using matrix product states
Energy Technology Data Exchange (ETDEWEB)
Saito, H.; Jansen, K. [DESY Zeuthen (Germany). John von Neumann Institute for Computing; Banuls, M.C.; Cirac, J.I. [Max-Planck Institute of Quantum Optics, Garching (Germany); Cichy, K. [Frankfurt am Main Univ. (Germany). Inst. fuer Theoretische Physik; Poznan Univ. (Poland). Faculty of Physics
2015-11-15
The Schwinger model, or 1+1 dimensional QED, offers an interesting object of study, both at zero and non-zero temperature, because of its similarities to QCD. In this proceeding, we present the a full calculation of the temperature dependent chiral condensate of this model in the continuum limit using Matrix Product States (MPS). MPS methods, in general tensor networks, constitute a very promising technique for the non-perturbative study of Hamiltonian quantum systems. In the last few years, they have shown their suitability as ansatzes for ground states and low-lying excitations of lattice gauge theories. We show the feasibility of the approach also for finite temperature, both in the massless and in the massive case.
Modelling of the Contact Condition at the Tool/Matrix Interface in Friction Stir Welding
DEFF Research Database (Denmark)
Schmidt, Henrik Nikolaj Blich; Hattel, Jesper; Wert, John
2003-01-01
is governed by the contact condition, i.e. whether there is sliding, sticking or partial sliding/sticking. The contact condition in FSW is complex (dependent on alloy, welding parameters, tool design etc.), and previous models (both analytical and numerical) for simulation of the heat generation assume......The objective of the present paper is to investigate the heat generation and contact condition during Friction Stir Welding (FSW). For this purpose, an analytical model is developed for the heat generation and this is combined with a Eulerian FE-analysis of the temperature field. The heat...... generation is closely related to the friction condition at the contact interface between the FSW tool and the weld piece material as well as the material flow in the weld matrix, since the mechanisms for heat generation by frictional and plastic dissipation are different. The heat generation from the tool...
String states, loops and effective actions in noncommutative field theory and matrix models
Directory of Open Access Journals (Sweden)
Harold C. Steinacker
2016-09-01
Full Text Available Refining previous work by Iso, Kawai and Kitazawa, we discuss bi-local string states as a tool for loop computations in noncommutative field theory and matrix models. Defined in terms of coherent states, they exhibit the stringy features of noncommutative field theory. This leads to a closed form for the 1-loop effective action in position space, capturing the long-range non-local UV/IR mixing for scalar fields. The formalism applies to generic fuzzy spaces. The non-locality is tamed in the maximally supersymmetric IKKT or IIB model, where it gives rise to supergravity. The linearized supergravity interactions are obtained directly in position space at one loop using string states on generic noncommutative branes.
Anomaly in RTT relation for DIM algebra and network matrix models
Directory of Open Access Journals (Sweden)
Hidetoshi Awata
2017-05-01
Full Text Available We discuss the recent proposal of arXiv:1608.05351 about generalization of the RTT relation to network matrix models. We show that the RTT relation in these models is modified by a nontrivial, but essentially abelian anomaly cocycle, which we explicitly evaluate for the free field representations of the quantum toroidal algebra. This cocycle is responsible for the braiding, which permutes the external legs in the q-deformed conformal block and its 5d/6d gauge theory counterpart, i.e. the non-perturbative Nekrasov functions. Thus, it defines their modular properties and symmetry. We show how to cancel the anomaly using a construction somewhat similar to the anomaly matching condition in gauge theory. We also describe the singular limit to the affine Yangian (4d Nekrasov functions, which breaks the spectral duality.
String states, loops and effective actions in noncommutative field theory and matrix models
Energy Technology Data Exchange (ETDEWEB)
Steinacker, Harold C., E-mail: harold.steinacker@univie.ac.at
2016-09-15
Refining previous work by Iso, Kawai and Kitazawa, we discuss bi-local string states as a tool for loop computations in noncommutative field theory and matrix models. Defined in terms of coherent states, they exhibit the stringy features of noncommutative field theory. This leads to a closed form for the 1-loop effective action in position space, capturing the long-range non-local UV/IR mixing for scalar fields. The formalism applies to generic fuzzy spaces. The non-locality is tamed in the maximally supersymmetric IKKT or IIB model, where it gives rise to supergravity. The linearized supergravity interactions are obtained directly in position space at one loop using string states on generic noncommutative branes.
Binary modelling the milling of UG2 ore using a matrix approach
Directory of Open Access Journals (Sweden)
Méschac-Bill Kime
2017-04-01
Full Text Available The study reports a binary matrix modelling and simulation studies to improve the performance of the secondary grinding circuit of UG2 ores. The model developed was intended to help searching for optimal operating conditions of the secondary milling circuit so that the platinum group element (PGE recovery is increased while reducing Cr2O3 entrainment in the subsequent flotation stage. A series of laboratory batch-scale tests was carried out in order to estimate the milling kinetics parameters of the chromite and non-chromite components. Finally, two alternatives circuit configurations for a better performance were evaluated using simulations. The optimal design consisted of a conventional ball mill in closed circuit with a hydrocyclone to separate the milling product into lights (non-chromite-rich and heavies (chromite-rich fractions followed by a vibrating screen to de-slime the cyclone underflow before it is returned to the mill for further grinding.
Sparse modeling of EELS and EDX spectral imaging data by nonnegative matrix factorization
Energy Technology Data Exchange (ETDEWEB)
Shiga, Motoki, E-mail: shiga_m@gifu-u.ac.jp [Department of Electrical, Electronic and Computer Engineering, Gifu University, 1-1, Yanagido, Gifu 501-1193 (Japan); Tatsumi, Kazuyoshi; Muto, Shunsuke [Advanced Measurement Technology Center, Institute of Materials and Systems for Sustainability, Nagoya University, Chikusa-ku, Nagoya 464-8603 (Japan); Tsuda, Koji [Graduate School of Frontier Sciences, University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa 277-8561 (Japan); Center for Materials Research by Information Integration, National Institute for Materials Science, 1-2-1 Sengen, Tsukuba 305-0047 (Japan); Biotechnology Research Institute for Drug Discovery, National Institute of Advanced Industrial Science and Technology, 2-4-7 Aomi Koto-ku, Tokyo 135-0064 (Japan); Yamamoto, Yuta [High-Voltage Electron Microscope Laboratory, Institute of Materials and Systems for Sustainability, Nagoya University, Chikusa-ku, Nagoya 464-8603 (Japan); Mori, Toshiyuki [Environment and Energy Materials Division, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044 (Japan); Tanji, Takayoshi [Division of Materials Research, Institute of Materials and Systems for Sustainability, Nagoya University, Chikusa-ku, Nagoya 464-8603 (Japan)
2016-11-15
Advances in scanning transmission electron microscopy (STEM) techniques have enabled us to automatically obtain electron energy-loss (EELS)/energy-dispersive X-ray (EDX) spectral datasets from a specified region of interest (ROI) at an arbitrary step width, called spectral imaging (SI). Instead of manually identifying the potential constituent chemical components from the ROI and determining the chemical state of each spectral component from the SI data stored in a huge three-dimensional matrix, it is more effective and efficient to use a statistical approach for the automatic resolution and extraction of the underlying chemical components. Among many different statistical approaches, we adopt a non-negative matrix factorization (NMF) technique, mainly because of the natural assumption of non-negative values in the spectra and cardinalities of chemical components, which are always positive in actual data. This paper proposes a new NMF model with two penalty terms: (i) an automatic relevance determination (ARD) prior, which optimizes the number of components, and (ii) a soft orthogonal constraint, which clearly resolves each spectrum component. For the factorization, we further propose a fast optimization algorithm based on hierarchical alternating least-squares. Numerical experiments using both phantom and real STEM-EDX/EELS SI datasets demonstrate that the ARD prior successfully identifies the correct number of physically meaningful components. The soft orthogonal constraint is also shown to be effective, particularly for STEM-EELS SI data, where neither the spatial nor spectral entries in the matrices are sparse. - Highlights: • Automatic resolution of chemical components from spectral imaging is considered. • We propose a new non-negative matrix factorization with two new penalties. • The first penalty is sparseness to choose the number of components from data. • Experimental results with real data demonstrate effectiveness of our method.
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Sette Alessandro
2005-05-01
Full Text Available Abstract Background Many processes in molecular biology involve the recognition of short sequences of nucleic-or amino acids, such as the binding of immunogenic peptides to major histocompatibility complex (MHC molecules. From experimental data, a model of the sequence specificity of these processes can be constructed, such as a sequence motif, a scoring matrix or an artificial neural network. The purpose of these models is two-fold. First, they can provide a summary of experimental results, allowing for a deeper understanding of the mechanisms involved in sequence recognition. Second, such models can be used to predict the experimental outcome for yet untested sequences. In the past we reported the development of a method to generate such models called the Stabilized Matrix Method (SMM. This method has been successfully applied to predicting peptide binding to MHC molecules, peptide transport by the transporter associated with antigen presentation (TAP and proteasomal cleavage of protein sequences. Results Herein we report the implementation of the SMM algorithm as a publicly available software package. Specific features determining the type of problems the method is most appropriate for are discussed. Advantageous features of the package are: (1 the output generated is easy to interpret, (2 input and output are both quantitative, (3 specific computational strategies to handle experimental noise are built in, (4 the algorithm is designed to effectively handle bounded experimental data, (5 experimental data from randomized peptide libraries and conventional peptides can easily be combined, and (6 it is possible to incorporate pair interactions between positions of a sequence. Conclusion Making the SMM method publicly available enables bioinformaticians and experimental biologists to easily access it, to compare its performance to other prediction methods, and to extend it to other applications.
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Shengmao Lin
2015-08-01
Full Text Available Scaffold mechanical properties are essential in regulating the microenvironment of three-dimensional cell culture. A coupled fiber-matrix numerical model was developed in this work for predicting the mechanical response of collagen scaffolds subjected to various levels of non-enzymatic glycation and collagen concentrations. The scaffold was simulated by a Voronoi network embedded in a matrix. The computational model was validated using published experimental data. Results indicate that both non-enzymatic glycation-induced matrix stiffening and fiber network density, as regulated by collagen concentration, influence scaffold behavior. The heterogeneous stress patterns of the scaffold were induced by the interfacial mechanics between the collagen fiber network and the matrix. The knowledge obtained in this work could help to fine-tune the mechanical properties of collagen scaffolds for improved tissue regeneration applications.
Rotmans, J.I.; Velema, E.; Verhagen, H.J.; Blankensteijn, J.D.; Kleijn, D.P. de; Stroes, E.S.; Pasterkamp, G.
2004-01-01
BACKGROUND: The patency of arteriovenous (AV) polytetrafluoroethylene grafts for hemodialysis is impaired by intimal hyperplasia (IH) at the venous outflow tract. IH mainly consists of vascular smooth muscle cells, fibroblasts, and extracellular matrix proteins. Because matrix metalloproteinases
Rotmans, JI; Velema, E; Verhagen, HJM; Blankensteijn, JD; de Kleijn, DPV; Stroes, ESG; Pasterkamp, G
Background: The patency of arteriovenous (AV) polytetrafluoroethylene grafts for hemodialysis is impaired by intimal hyperplasia (IH) at the venous outflow tract. IH mainly consists of vascular smooth muscle cells, fibroblasts, and extracellular matrix proteins. Because matrix metalloproteinases
Constructing stage-structured matrix population models from life tables: comparison of methods.
Fujiwara, Masami; Diaz-Lopez, Jasmin
2017-01-01
A matrix population model is a convenient tool for summarizing per capita survival and reproduction rates (collectively vital rates) of a population and can be used for calculating an asymptotic finite population growth rate ( λ ) and generation time. These two pieces of information can be used for determining the status of a threatened species. The use of stage-structured population models has increased in recent years, and the vital rates in such models are often estimated using a life table analysis. However, potential bias introduced when converting age-structured vital rates estimated from a life table into parameters for a stage-structured population model has not been assessed comprehensively. The objective of this study was to investigate the performance of methods for such conversions using simulated life histories of organisms. The underlying models incorporate various types of life history and true population growth rates of varying levels. The performance was measured by comparing differences in λ and the generation time calculated using the Euler-Lotka equation, age-structured population matrices, and several stage-structured population matrices that were obtained by applying different conversion methods. The results show that the discretization of age introduces only small bias in λ or generation time. Similarly, assuming a fixed age of maturation at the mean age of maturation does not introduce much bias. However, aggregating age-specific survival rates into a stage-specific survival rate and estimating a stage-transition rate can introduce substantial bias depending on the organism's life history type and the true values of λ . In order to aggregate survival rates, the use of the weighted arithmetic mean was the most robust method for estimating λ . Here, the weights are given by survivorship curve after discounting with λ . To estimate a stage-transition rate, matching the proportion of individuals transitioning, with λ used for discounting
Constructing stage-structured matrix population models from life tables: comparison of methods
Directory of Open Access Journals (Sweden)
Masami Fujiwara
2017-10-01
Full Text Available A matrix population model is a convenient tool for summarizing per capita survival and reproduction rates (collectively vital rates of a population and can be used for calculating an asymptotic finite population growth rate (λ and generation time. These two pieces of information can be used for determining the status of a threatened species. The use of stage-structured population models has increased in recent years, and the vital rates in such models are often estimated using a life table analysis. However, potential bias introduced when converting age-structured vital rates estimated from a life table into parameters for a stage-structured population model has not been assessed comprehensively. The objective of this study was to investigate the performance of methods for such conversions using simulated life histories of organisms. The underlying models incorporate various types of life history and true population growth rates of varying levels. The performance was measured by comparing differences in λ and the generation time calculated using the Euler-Lotka equation, age-structured population matrices, and several stage-structured population matrices that were obtained by applying different conversion methods. The results show that the discretization of age introduces only small bias in λ or generation time. Similarly, assuming a fixed age of maturation at the mean age of maturation does not introduce much bias. However, aggregating age-specific survival rates into a stage-specific survival rate and estimating a stage-transition rate can introduce substantial bias depending on the organism’s life history type and the true values of λ. In order to aggregate survival rates, the use of the weighted arithmetic mean was the most robust method for estimating λ. Here, the weights are given by survivorship curve after discounting with λ. To estimate a stage-transition rate, matching the proportion of individuals transitioning, with λ used
Ray, Subir K; Chandel, Shubham; Singh, Ankit K; Kumar, Abhishek; Mandal, Arpita; Misra, Subhradeep; Mitra, Partha; Ghosh, Nirmalya
2017-02-28
Fano resonance is observed in a wide range of micro- and nano-optical systems and has been a subject of intensive investigations due to its numerous potential applications. Methods that can control or modulate Fano resonance by tuning some experimentally accessible parameters are highly desirable for realistic applications. Here we present a simple yet elegant approach using the Mueller matrix formalism for controlling the Fano interference effect and engineering the resulting asymmetric spectral line shape in an anisotropic optical system. The approach is founded on a generalized model of anisotropic Fano resonance, which relates the spectral asymmetry to physically meaningful and experimentally accessible parameters of interference, namely, the Fano phase shift and the relative amplitudes of the interfering modes. The differences in these parameters between orthogonal linear polarizations in an anisotropic system are exploited to desirably tune the Fano spectral asymmetry using pre- and postselection of optimized polarization states. The concept is demonstrated on waveguided plasmonic crystals using Mueller matrix-based polarization analysis. The approach enabled tailoring of several exotic regimes of Fano resonance in a single device, including the complete reversal of the spectral asymmetry, and shows potential for applications involving control and manipulation of electromagnetic waves at the nanoscale.
Energy Technology Data Exchange (ETDEWEB)
Shirvanimoghaddam, K., E-mail: kshirvan@deakin.edu.au [Institute for Frontier Materials, Deakin University, Waurn Ponds, Geelong, Victoria 3216 (Australia); Khayyam, H. [Institute for Frontier Materials, Deakin University, Waurn Ponds, Geelong, Victoria 3216 (Australia); Abdizadeh, H. [School of Metallurgy and Materials Engineering, University of Tehran, P.O. Box 11365-4563, Tehran (Iran, Islamic Republic of); Karbalaei Akbari, M. [Faculty of Metallurgical and Materials Engineering, Semnan University, P.O. Box 35131-19111, Semnan (Iran, Islamic Republic of); Pakseresht, A.H.; Ghasali, E. [Materials and Energy Research Centre, P.O. Box 31787-316, Karaj (Iran, Islamic Republic of); Naebe, M., E-mail: minoo.naebe@deakin.edu.au [Institute for Frontier Materials, Deakin University, Waurn Ponds, Geelong, Victoria 3216 (Australia)
2016-03-21
This paper investigates the manufacturing of aluminium–boron carbide composites using the stir casting method. Mechanical and physical properties tests to obtain hardness, ultimate tensile strength (UTS) and density are performed after solidification of specimens. The results show that hardness and tensile strength of aluminium based composite are higher than monolithic metal. Increasing the volume fraction of B{sub 4}C, enhances the tensile strength and hardness of the composite; however over-loading of B{sub 4}C caused particle agglomeration, rejection from molten metal and migration to slag. This phenomenon decreases the tensile strength and hardness of the aluminium based composite samples cast at 800 °C. For Al-15 vol% B{sub 4}C samples, the ultimate tensile strength and Vickers hardness of the samples that were cast at 1000 °C, are the highest among all composites. To predict the mechanical properties of aluminium matrix composites, two key prediction modelling methods including Neural Network learned by Levenberg–Marquardt Algorithm (NN-LMA) and Thin Plate Spline (TPS) models are constructed based on experimental data. Although the results revealed that both mathematical models of mechanical properties of Al–B{sub 4}C are reliable with a high level of accuracy, the TPS models predict the hardness and tensile strength values with less error compared to NN-LMA models.
Modeling of highly loaded 0-3 piezoelectric composites using a matrix method.
Levassort, F; Lethiecq, M; Millar, C; Pourcelot, L
1998-01-01
A model previously developed for pure 0-3 connectivity piezocomposites has been extended to 3-3 connectivity. This matrix method allows the prediction of the effective electroelastic moduli of a piezocomposite according to its connectivity. It is used to optimize composite performance by choosing the optimal constituents for each phase. A simple combination of the results for 0-3 and 3-3 connectivities allows the effective proportion of 3-3 connectivity to be defined in highly loaded 0-3 piezocomposites. This theoretical analysis has been used to evaluate effective proportions of 3-3 connectivity in five composite samples. The values obtained are shown to be a function of the ceramic volume fraction and fabrication process. The results of this study were used to optimize the fabrication process.
Jiang, Yunpeng; Qiu, Kun; Sun, Longgang; Wu, Qingqing
2018-01-01
The relationship among processing, microstructure, and mechanical performance is the most important for metallic glass matrix composites (MGCs). Numerical modeling was performed on the shear banding in MGCs, and the impacts of particle concentration, morphology, agglomerate, size, and thermal residual stress were revealed. Based on the shear damage criterion, the equivalent plastic strain acted as an internal state variable to depict the nucleation, growth, and coalescence of shear bands. The element deletion technique was employed to describe the process of transformation from shear band to micro-crack. The impedance effect of particle morphology on the propagation of shear bands was discussed, whereby the toughening mechanism was clearly interpreted. The present work contributes to the subsequent strengthening and toughening design of MGCs.
Evidence for fast thermalization in the plane-wave matrix model.
Asplund, Curtis T; Berenstein, David; Trancanelli, Diego
2011-10-21
We report on a numerical simulation of the classical evolution of the plane-wave matrix model with semiclassical initial conditions. Some of these initial conditions thermalize and are dual to a black hole forming from the collision of D-branes in the plane-wave geometry. In particular, we consider a large fuzzy sphere (a D2-brane) plus a single eigenvalue (a D0 particle) going exactly through the center of the fuzzy sphere and aimed to intersect it. Including quantum fluctuations of the off-diagonal modes in the initial conditions, with sufficient kinetic energy the configuration collapses to a small size. We also find evidence for fast thermalization: rapidly decaying autocorrelation functions at late times with respect to the natural time scale of the system. © 2011 American Physical Society
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Liu, Yizhuang, E-mail: yizhuang.liu@stonybrook.edu [Department of Physics and Astronomy, Stony Brook University, Stony Brook, NY 11794-3800 (United States); Nowak, Maciej A., E-mail: maciej.a.nowak@uj.edu.pl [M. Smoluchowski Institute of Physics and Mark Kac Complex Systems Research Center, Jagiellonian University, PL-30348 Krakow (Poland); Zahed, Ismail, E-mail: ismail.zahed@stonybrook.edu [Department of Physics and Astronomy, Stony Brook University, Stony Brook, NY 11794-3800 (United States)
2016-08-15
We derive an exact formula for the stochastic evolution of the characteristic determinant of a class of deformed Wishart matrices following from a chiral random matrix model of QCD at finite chemical potential. In the WKB approximation, the characteristic determinant describes a sharp droplet of eigenvalues that deforms and expands at large stochastic times. Beyond the WKB limit, the edges of the droplet are fuzzy and described by universal edge functions. At the chiral point, the characteristic determinant in the microscopic limit is universal. Remarkably, the physical chiral condensate at finite chemical potential may be extracted from current and quenched lattice Dirac spectra using the universal edge scaling laws, without having to solve the QCD sign problem.
Cramer, Gwendolyn M.; El-Hamidi, Hamid; Celli, Jonathan P.
2017-02-01
Pancreatic ductal adenocarcinoma (PDAC) is characterized by extracellular matrix-rich stromal involvement, but it is not clear how ECM properties that affect invasiveness and chemotherapy response influence efficacy of photodynamic therapy (PDT). To disentangle the mechanical and biochemical effects of ECM composition, we measured the effects of various combinations of ECM proteins on growth behavior, invasive potential, and therapeutic response of multicellular 3D pancreatic tumor models. These spheroids were grown in attachment-free conditions before embedding in combinations of rheologically characterized collagen 1 and Matrigel combinations and treated with oxaliplatin chemotherapy and PDT. We find that cells invading from collagen-embedded tumor spheroids, the least rigid ECM substrate described here, displayed better response to PDT than to oxaliplatin chemotherapy. Overall, our results support that ECM-mediated invading PDAC populations remain responsive to PDT in conditions that induce chemoresistance.
A non-equilibrium thermodynamic model for tumor extracellular matrix with enzymatic degradation
Xue, Shi-Lei; Li, Bo; Feng, Xi-Qiao; Gao, Huajian
2017-07-01
The extracellular matrix (ECM) of a solid tumor not only affords scaffolding to support tumor architecture and integrity but also plays an essential role in tumor growth, invasion, metastasis, and therapeutics. In this paper, a non-equilibrium thermodynamic theory is established to study the chemo-mechanical behaviors of tumor ECM, which is modeled as a poroelastic polyelectrolyte consisting of a collagen network and proteoglycans. By using the principle of maximum energy dissipation rate, we deduce a set of governing equations for drug transport and mechanosensitive enzymatic degradation in ECM. The results reveal that osmosis is primarily responsible for the compression resistance of ECM. It is suggested that a well-designed ECM degradation can effectively modify the tumor microenvironment for improved efficiency of cancer therapy. The theoretical predictions show a good agreement with relevant experimental observations. This study aimed to deepen our understanding of tumor ECM may be conducive to novel anticancer strategies.
Should We Care that Johnny Can't Catch and Susie Can't Skip? What Should We Do about It?
Whitall, Jill; Clark, Jane E.
2011-01-01
Physical and sport educators care that Johnny and Susie cannot move as well as their peers. They try their best to improve their skill levels because they value participation and skillfulness in sport and physical activity. However, many times there is a deeper problem as to why Johnny or Susie cannot move as well as their peers. Physical and…
Ellison, Donald; Conway, Bruce; Englander, Jacob
2015-01-01
A significant body of work exists showing that providing a nonlinear programming (NLP) solver with expressions for the problem constraint gradient substantially increases the speed of program execution and can also improve the robustness of convergence, especially for local optimizers. Calculation of these derivatives is often accomplished through the computation of spacecraft's state transition matrix (STM). If the two-body gravitational model is employed as is often done in the context of preliminary design, closed form expressions for these derivatives may be provided. If a high fidelity dynamics model, that might include perturbing forces such as the gravitational effect from multiple third bodies and solar radiation pressure is used then these STM's must be computed numerically. We present a method for the power hardward model and a full ephemeris model. An adaptive-step embedded eight order Dormand-Prince numerical integrator is discussed and a method for the computation of the time of flight derivatives in this framework is presented. The use of these numerically calculated derivatieves offer a substantial improvement over finite differencing in the context of a global optimizer. Specifically the inclusion of these STM's into the low thrust missiondesign tool chain in use at NASA Goddard Spaceflight Center allows for an increased preliminary mission design cadence.
Estrada-Peña, A; Estrada-Sánchez, D
2014-03-01
A stage-structured Leslie matrix model of a partial, discrete population of Ixodes ricinus (Linnaeus) (Ixodida: Ixodidae) ticks was developed to elucidate the impact of climate trends on the distribution and phenology of this species in the western Palaearctic. The model calculates development and mortality rates for each instar and evaluates recruitment rates based on the development of the tick population. The model captures the changes in development and mortality rates, providing a coherent index of performance correlated with the tick's geographic range. Maximum development rates are recorded for latitudes south of 36 °N and are spatially correlated with sites of maximum temperature, highest saturation deficit and highest mortality. The maximum available developmental time (the total annual time during which temperature allows development) for I. ricinus in the western Palaearctic is < 45% of the total year. North of 60 °N, available developmental time decreases sharply to only 15% of the year. The latitudinal boundary at which survival rates sharply drop is 43-46 °N, clearly delimiting the classically recognized extent of the main tick populations. The pattern of activity for larval-nymphal synchrony shows a clear west-east pattern. The model demonstrates the impact of climate according to tick stage and geographic location, and provides a practical framework for testing how the tick's lifecycle is affected by climate change. © 2013 The Royal Entomological Society.
ABOUT THE INFORMATIZATION MANAGING OF THE PRODUCTION SYSTEM BASED ON THE MATRIX MODEL
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Aleksandr V. Romanenko
2016-06-01
Full Text Available Introduction. The problem of formation and information management systems management of manufacturing system businesses is analyzed in the article. Existing schemes of the Russian economy increased demands for its efficiency. Stability integrative model business entity lifecycle requires a search for solutions based on new technologies in the organization and operation of information management systems. Results. On the basis of the analysis of their importance for sustainability of the entity components of its life cycle conclusions are made about the applicability of the matrix model to the production system management. Contradiction in the application of this management model are solved by separating the information on the basis of the state of product and process state. This division contributes to a better organization of the distribution of responsibility between the profit centers and cost centers. As an indicator of the efficiency of profit centers, it is proposed to use the ratio revenue net from the sale of products to the current value of the planned costs of its production. To assess the effectiveness of cost centers used index that is similar to profitability of fixed assets taking into account the cost of resources utilized by each cost center separately. Discussion and Conclusions. We analyze the relationship between goals management of the production system with the role of profit centers and cost centers. The proposed basis of the formation model information ensures the management of the production system, contributing to improve the quality of managerial decisions in implementing the competitive advantages of business entity.
Mondaini, Rubem; Rigol, Marcos
2017-07-01
We study the matrix elements of few-body observables, focusing on the off-diagonal ones, in the eigenstates of the two-dimensional transverse field Ising model. By resolving all symmetries, we relate the onset of quantum chaos to the structure of the matrix elements. In particular, we show that a general result of the theory of random matrices, namely, the value 2 of the ratio of variances (diagonal to off-diagonal) of the matrix elements of Hermitian operators, occurs in the quantum chaotic regime. Furthermore, we explore the behavior of the off-diagonal matrix elements of observables as a function of the eigenstate energy differences and show that it is in accordance with the eigenstate thermalization hypothesis ansatz.
Rupp, Andre A.; Templin, Jonathan
2008-01-01
This article reports a study that investigated the effects of Q-matrix misspecifications on parameter estimates and misclassification rates for the deterministic-input, noisy "and" gate (DINA) model, which is a restricted latent class model for multiple classifications of respondents that can be useful for cognitively motivated diagnostic…
Hemerik, L.; Klok, C.
2006-01-01
Due to human activity, many species have strongly declined in number and are currently threatened with extinction. Management directed at conservation of these species can benefit from the use of simple population models such as matrix models. However, for many species, data on survival and
An Open-Access Modeled Passenger Flow Matrix for the Global Air Network in 2010
Huang, Zhuojie; Wu, Xiao; Garcia, Andres J.; Fik, Timothy J.; Tatem, Andrew J.
2013-01-01
The expanding global air network provides rapid and wide-reaching connections accelerating both domestic and international travel. To understand human movement patterns on the network and their socioeconomic, environmental and epidemiological implications, information on passenger flow is required. However, comprehensive data on global passenger flow remain difficult and expensive to obtain, prompting researchers to rely on scheduled flight seat capacity data or simple models of flow. This study describes the construction of an open-access modeled passenger flow matrix for all airports with a host city-population of more than 100,000 and within two transfers of air travel from various publicly available air travel datasets. Data on network characteristics, city population, and local area GDP amongst others are utilized as covariates in a spatial interaction framework to predict the air transportation flows between airports. Training datasets based on information from various transportation organizations in the United States, Canada and the European Union were assembled. A log-linear model controlling the random effects on origin, destination and the airport hierarchy was then built to predict passenger flows on the network, and compared to the results produced using previously published models. Validation analyses showed that the model presented here produced improved predictive power and accuracy compared to previously published models, yielding the highest successful prediction rate at the global scale. Based on this model, passenger flows between 1,491 airports on 644,406 unique routes were estimated in the prediction dataset. The airport node characteristics and estimated passenger flows are freely available as part of the Vector-Borne Disease Airline Importation Risk (VBD-Air) project at: www.vbd-air.com/data. PMID:23691194
SUSY and BSM Higgs boson searches with ATLAS and CMS
Dasu, S
2012-01-01
Results of searches for super-symmetric and other beyond the Standard Model Higgs boson searches from ATLAS and CMS experiments at the LHC arc presented. Some Standard Model (SM) higgs searches are reinterpreted in SM with four quark generations and fermio phobic models. Stringent limits) covering a large portion of the allowed parameter space in (MA, tan/3) plane are set for MSSM neutral higgs bosons decaying to T-lepton pairs, and charged higgs boson decaying to TV. Limits are set on a light NMSSM neutral higgs boson and on doubly charged higgs bosons predicted in some models are also set.
Closing up a light stop window in natural SUSY at LHC
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Archil Kobakhidze
2016-04-01
Full Text Available Top squark (stop plays a key role in the radiative stability of the Higgs boson mass in supersymmetry (SUSY. In this work, we use the LHC Run-1 data to determine the lower mass limit of the right-handed stop in a natural SUSY scenario, where the higgsinos χ˜1,20 and χ˜1± are light and nearly degenerate. We find that the stop mass has been excluded up to 430 GeV for mχ˜10≲250 GeV and to 540 GeV for mχ˜10≃100 GeV by the Run-1 SUSY searches for 2b+ETmiss and 1ℓ+jets+ETmiss, respectively. In a small strip of parameter space with mχ˜10≳190 GeV, the stop mass can still be as light as 210 GeV and compatible with the Higgs mass measurement and the monojet bound. The 14 TeV LHC with a luminosity of 20 fb−1 can further cover such a light stop window by monojet and 2b+ETmiss searches and push the lower bound of the stop mass to 710 GeV. We also explore the potential to use the Higgs golden ratio, Dγγ=σ(pp→h→γγ/σ(pp→h→ZZ⁎→4ℓ±, as a complementary probe for the light and compressed stop. If this golden ratio can be measured at percent level at the high luminosity LHC (HL-LHC or future e+e− colliders, the light stop can be excluded for most of the currently allowed parameter region.
Energy Technology Data Exchange (ETDEWEB)
Cwik, T.; Jamnejad, V.; Zuffada, C. [California Institute of Technology, Pasadena, CA (United States)
1994-12-31
The usefulness of finite element modeling follows from the ability to accurately simulate the geometry and three-dimensional fields on the scale of a fraction of a wavelength. To make this modeling practical for engineering design, it is necessary to integrate the stages of geometry modeling and mesh generation, numerical solution of the fields-a stage heavily dependent on the efficient use of a sparse matrix equation solver, and display of field information. The stages of geometry modeling, mesh generation, and field display are commonly completed using commercially available software packages. Algorithms for the numerical solution of the fields need to be written for the specific class of problems considered. Interior problems, i.e. simulating fields in waveguides and cavities, have been successfully solved using finite element methods. Exterior problems, i.e. simulating fields scattered or radiated from structures, are more difficult to model because of the need to numerically truncate the finite element mesh. To practically compute a solution to exterior problems, the domain must be truncated at some finite surface where the Sommerfeld radiation condition is enforced, either approximately or exactly. Approximate methods attempt to truncate the mesh using only local field information at each grid point, whereas exact methods are global, needing information from the entire mesh boundary. In this work, a method that couples three-dimensional finite element (FE) solutions interior to the bounding surface, with an efficient integral equation (IE) solution that exactly enforces the Sommerfeld radiation condition is developed. The bounding surface is taken to be a surface of revolution (SOR) to greatly reduce computational expense in the IE portion of the modeling.
Thimble regularization at work: From toy models to chiral random matrix theories
Di Renzo, F.; Eruzzi, G.
2015-10-01
We apply the Lefschetz thimble formulation of field theories to a couple of different problems. We first address the solution of a complex zero-dimensional ϕ4 theory. Although very simple, this toy model makes us appreciate a few key issues of the method. In particular, we will solve the model by a correct accounting of all the thimbles giving a contribution to the partition function and we will discuss a number of algorithmic solutions to simulate this (simple) model. We will then move to a chiral random matrix (CRM) theory. This is a somehow more realistic setting, giving us once again the chance to tackle the same couple of fundamental questions: How many thimbles contribute to the solution? How can we make sure that we correctly sample configurations on the thimble? Since the exact result is known for the observable we study (a condensate), we can verify that, in the region of parameters we studied, only one thimble contributes and that the algorithmic solution that we set up works well, despite its very crude nature. The deviation of results from phase quenched ones highlights that in a certain region of parameter space there is a quite important sign problem. In view of this, the success of our thimble approach is quite a significant one.
Directory of Open Access Journals (Sweden)
Mircia Eleonora
2015-12-01
Full Text Available Pentoxifylline is a xanthine derivative used in the treatment of peripheral vascular disease, which because of its pharmacokinetic and pharmacologic profile is an ideal candidate for the development of extended release formulations. The aim of this study is to present a kinetic analysis of the pentoxifylline release from different extended release tablets formulations, using mechanistic and empirical kinetic models. A number of 28 formulations were prepared and analysed; the analysed formulations differed in the nature of the matrix forming polymers (hydrophilic, lipophilic, inert and in their concentrations. Measurements were conducted in comparison with the reference product Trental 400 mg (Aventis Pharma. The conditions for the dissolution study were according to official regulations of USP 36: apparatus no. 2, dissolution medium water, volume of dissolution medium is 1,000 mL, rotation speed is 50 rpm, spectrophotometric assay at 274 nm. Six mathematical models, five mechanistic (0 orders, 1st-order release, Higuchi, Hopfenberg, Hixson-Crowell and one empirical (Peppas, were fitted to pentoxifylline dissolution profile from each pharmaceutical formulation. The representative model describing the kinetics of pentoxifylline release was the 1st-order release, and its characteristic parameters were calculated and analysed.
Thimble regularization at work: from toy models to chiral random matrix theories
Di Renzo, Francesco
2015-01-01
We apply the Lefschetz thimble formulation of field theories to a couple of different problems. We first address the solution of a complex 0-dimensional phi^4 theory. Although very simple, this toy-model makes us appreciate a few key issues of the method. In particular, we will solve the model by a correct accounting of all the thimbles giving a contribution to the partition function and we will discuss a number of algorithmic solutions to simulate this (simple) model. We will then move to a chiral random matrix (CRM) theory. This is a somehow more realistic setting, giving us once again the chance to tackle the same couple of fundamental questions: how many thimbles contribute to the solution? how can we make sure that we correctly sample configurations on the thimble? Since the exact result is known for the observable we study (a condensate), we can verify that, in the region of parameters we studied, only one thimble contributes and that the algorithmic solution that we set up works well, despite its very ...
On the Free Vibration Modeling of Spindle Systems: A Calibrated Dynamic Stiffness Matrix
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Omar Gaber
2014-01-01
Full Text Available The effect of bearings on the vibrational behavior of machine tool spindles is investigated. This is done through the development of a calibrated dynamic stiffness matrix (CDSM method, where the bearings flexibility is represented by massless linear spring elements with tuneable stiffness. A dedicated MATLAB code is written to develop and to assemble the element stiffness matrices for the system’s multiple components and to apply the boundary conditions. The developed method is applied to an illustrative example of spindle system. When the spindle bearings are modeled as simply supported boundary conditions, the DSM model results in a fundamental frequency much higher than the system’s nominal value. The simply supported boundary conditions are then replaced by linear spring elements, and the spring constants are adjusted such that the resulting calibrated CDSM model leads to the nominal fundamental frequency of the spindle system. The spindle frequency results are also validated against the experimental data. The proposed method can be effectively applied to predict the vibration characteristics of spindle systems supported by bearings.
Gamberg, Leonard; Mukherjee, Asmita; Mulders, Piet J.
2010-01-01
Gluonic pole matrix elements explain the appearance of single spin asymmetries (SSA) in high-energy scattering processes. They involve a combination of operators which are odd under time reversal (T-odd). Such matrix elements appear in principle both for parton distribution functions and parton fragmentation functions. We show that for parton fragmentation functions these gluonic pole matrix elements vanish as a consequence of the analytic structure of scattering amplitudes in Quantum Chromod...
Neutrino masses from SUSY: Different contributions and their ...
Indian Academy of Sciences (India)
We discuss the various sources of neutrino masses in supersymmetric standard models with explicit lepton number violation. We show that the bilinear lepton number violating soft terms in models with either bilinear or trilinear lepton number violating couplings in the superpotential, play an important role in determining the ...
Wang, Jian-Xun; Xiao, Heng
2016-01-01
Numerical models based on Reynolds-Averaged Navier-Stokes (RANS) equations are widely used in engineering turbulence modeling. However, the RANS predictions have large model-form uncertainties for many complex flows. Quantification of these large uncertainties originating from the modeled Reynolds stresses has attracted attention in turbulence modeling community. Recently, a physics-based Bayesian framework for quantifying model-form uncertainties has been proposed with successful applications to several flows. Nonetheless, how to specify proper priors without introducing unwarranted, artificial information remains challenging to the current form of the physics-based approach. Another recently proposed method based on random matrix theory provides the prior distributions with the maximum entropy, which is an alternative for model-form uncertainty quantification in RANS simulations. In this work, we utilize the random matrix theoretic approach to assess and possibly improve the specification of priors used in ...
Susy-QCD corrections to neutrlino pair production in association with a jet
Energy Technology Data Exchange (ETDEWEB)
Cullen, Gavin [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany); Greiner, Nicolas; Heinrich, Gudrun [Max-Planck-Institut fuer Physik, Muenchen (Germany)
2012-12-15
We present the NLO Susy-QCD corrections to the production of a pair of the lightest neutralinos plus one jet at the LHC, appearing as a monojet signature in combination with missing energy. We fully include all non-resonant diagrams, i.e. we do not assume that production and decay factorise. We derive a parameter point based on the p19MSSM which is compatible with current experimental bounds and show distributions based on missing transverse energy and jet observables. Our results are produced with the program GoSam for automated one-loop calculations in combination with MadDipole/- MadGraph for the real radiation part.
Duffy, Stephen F.
1998-01-01
The development of modeling approaches for the failure analysis of ceramic-based material systems used in high temperature environments was the primary objective of this research effort. These materials have the potential to support many key engineering technologies related to the design of aeropropulsion systems. Monolithic ceramics exhibit a number of useful properties such as retention of strength at high temperatures, chemical inertness, and low density. However, the use of monolithic ceramics has been limited by their inherent brittleness and a large variation in strength. This behavior has motivated material scientists to reinforce the monolithic material with a ceramic fiber. The addition of a second ceramic phase with an optimized interface increases toughness and marginally increases strength. The primary purpose of the fiber is to arrest crack growth, not to increase strength. The material systems of interest in this research effort were laminated ceramic matrix composites, as well as two- and three- dimensional fabric reinforced ceramic composites. These emerging composite systems can compete with metals in many demanding applications. However, the ongoing metamorphosis of ceramic composite material systems, and the lack of standardized design data has in the past tended to minimize research efforts related to structural analysis. Many structural components fabricated from ceramic matrix composites (CMC) have been designed by "trial and error." The justification for this approach lies in the fact that during the initial developmental phases for a material system fabrication issues are paramount. Emphasis is placed on demonstrating feasibility rather than fully understanding the processes controlling mechanical behavior. This is understandable during periods of rapid improvements in material properties for any composite system. But to avoid the ad hoc approach, the analytical methods developed under this effort can be used to develop rational structural
Madsen, Jonas S; Lin, Yu-Cheng; Squyres, Georgia R; Price-Whelan, Alexa; de Santiago Torio, Ana; Song, Angela; Cornell, William C; Sørensen, Søren J; Xavier, Joao B; Dietrich, Lars E P
2015-12-01
As biofilms grow, resident cells inevitably face the challenge of resource limitation. In the opportunistic pathogen Pseudomonas aeruginosa PA14, electron acceptor availability affects matrix production and, as a result, biofilm morphogenesis. The secreted matrix polysaccharide Pel is required for pellicle formation and for colony wrinkling, two activities that promote access to O2. We examined the exploitability and evolvability of Pel production at the air-liquid interface (during pellicle formation) and on solid surfaces (during colony formation). Although Pel contributes to the developmental response to electron acceptor limitation in both biofilm formation regimes, we found variation in the exploitability of its production and necessity for competitive fitness between the two systems. The wild type showed a competitive advantage against a non-Pel-producing mutant in pellicles but no advantage in colonies. Adaptation to the pellicle environment selected for mutants with a competitive advantage against the wild type in pellicles but also caused a severe disadvantage in colonies, even in wrinkled colony centers. Evolution in the colony center produced divergent phenotypes, while adaptation to the colony edge produced mutants with clear competitive advantages against the wild type in this O2-replete niche. In general, the structurally heterogeneous colony environment promoted more diversification than the more homogeneous pellicle. These results suggest that the role of Pel in community structure formation in response to electron acceptor limitation is unique to specific biofilm models and that the facultative control of Pel production is required for PA14 to maintain optimum benefit in different types of communities. Copyright © 2015, American Society for Microbiology. All Rights Reserved.
Directory of Open Access Journals (Sweden)
Jessica L. Ungerleider, BS
2016-01-01
Full Text Available Although surgical and endovascular revascularization can be performed in peripheral arterial disease (PAD, 40% of patients with critical limb ischemia do not have a revascularization option. This study examines the efficacy and mechanisms of action of acellular extracellular matrix-based hydrogels as a potential novel therapy for treating PAD. We tested the efficacy of using a tissue-specific injectable hydrogel derived from decellularized porcine skeletal muscle (SKM and compared this to a new human umbilical cord-derived matrix (hUC hydrogel, which could have greater potential for tissue regeneration because of the younger age of the tissue source. In a rodent hindlimb ischemia model, both hydrogels were injected 1-week post-surgery and perfusion was regularly monitored with laser speckle contrast analysis to 35 days post-injection. There were significant improvements in hindlimb tissue perfusion and perfusion kinetics with both biomaterials. Histologic analysis indicated that the injected hydrogels were biocompatible, and resulted in arteriogenesis, rather than angiogenesis, as well as improved recruitment of skeletal muscle progenitors. Skeletal muscle fiber morphology analysis indicated that the muscle treated with the tissue-specific SKM hydrogel more closely matched healthy tissue morphology. Whole transcriptome analysis indicated that the SKM hydrogel caused a shift in the inflammatory response, decreased cell death, and increased blood vessel and muscle development. These results show the efficacy of an injectable ECM hydrogel alone as a potential therapy for treating patients with PAD. Our results indicate that the SKM hydrogel improved functional outcomes through stimulation of arteriogenesis and muscle progenitor cell recruitment.
Directory of Open Access Journals (Sweden)
T. D. KUSWORO
2015-09-01
Full Text Available This paper investigates the effect of preparation of polyimide/polyethersulfone (PI/PES blending-zeolite mixed matrix membrane through the manipulation of membrane production variables such as polymer concentration, blending composition and zeolite loading. Combination of central composite design and response surface methodology were applied to determine the main effect and interaction effects of these variables on membrane separation performance. The quadratic models between each response and the independent parameters were developed and the response surface models were tested with analysis of variance (ANOVA. In this study, PI/ (PES–zeolite 4A mixed matrix membranes were casted using dry/wet phase inversion technique. The separation performance of mixed matrix membrane had been tested using pure gases such as CO2 and CH4. The results showed that zeolite loading was the most significant variable that influenced the CO2/CH4 selectivity among three variables and the experimental results were in good agreement with those predicted by the proposed regression models. The gas separation performance of the membrane was relatively higher as compare to polymeric membrane. Therefore, combination of central composite design and response surface methodology can be used to prepare optimal condition for mixed matrix membrane fabrication. The incorporation of 20 wt% zeolite 4A into 25 wt% of PI/PES matrix had resulted in a high separation performance of membrane material.
Energy Technology Data Exchange (ETDEWEB)
Nath, Pran
2012-09-12
SUSY2009 brought together researchers from a very broad area of fundamental physics including elementary particle theory, astrophysics and cosmology and string theory with a focus on supersymmetry. Thus the topic covered at the SUSY2009 conference included the following: Search for the Higgs boson, search for supersymmetry, supersymmetry phenomenology, theories of dark matter and direct and indirect detection, neutrino physics, accelerator experiments, electroweak physics, supersymmetry phenomenology, string theory, string phenomenology, extra Dimensions as well as other recent theoretical and experimental developments. The conference was successful in fostering interdisciplinary interactions between theorists and experimentalists.
Campagnola, Paul J.; Ajeti, Visar; Lara, Jorge; Eliceiri, Kevin W.; Patankar, Mansh
2016-04-01
A profound remodeling of the extracellular matrix (ECM) occurs in human ovarian cancer but it unknown how this affects tumor growth, where this understanding could lead to better diagnostics and therapeutic approaches. We investigate the role of these ECM alterations by using multiphoton excited (MPE) polymerization to fabricate biomimetic models to investigate operative cell-matrix interactions in invasion/metastasis. First, we create nano/microstructured gradients mimicking the basal lamina to study adhesion/migration dynamics of ovarian cancer cells of differing metastatic potential. We find a strong haptotactic response that depends on both contact guidance and ECM binding cues. While we found enhanced migration for more invasive cells, the specifics of alignment and directed migration also depend on cell polarity. We further use MPE fabrication to create collagen scaffolds with complex, 3D submicron morphology. The stromal scaffold designs are derived directly from "blueprints" based on SHG images of normal, high risk, and malignant ovarian tissues. The models are seeded with different cancer cell lines and this allows decoupling of the roles of cell characteristics (metastatic potential) and ECM structure and composition (normal vs cancer) on adhesion/migration dynamics. We found the malignant stroma structure promotes enhanced migration and proliferation and also cytoskeletal alignment. Creating synthetic models based on fibers patterns further allows decoupling the topographic roles of the fibers themselves vs their alignment within the tissue. These models cannot be synthesized by other conventional fabrication methods and we suggest the MPE image-based fabrication method will enable a variety of studies in cancer biology.
Incorporating uncertainty of management costs in sensitivity analyses of matrix population models.
Salomon, Yacov; McCarthy, Michael A; Taylor, Peter; Wintle, Brendan A
2013-02-01
The importance of accounting for economic costs when making environmental-management decisions subject to resource constraints has been increasingly recognized in recent years. In contrast, uncertainty associated with such costs has often been ignored. We developed a method, on the basis of economic theory, that accounts for the uncertainty in population-management decisions. We considered the case where, rather than taking fixed values, model parameters are random variables that represent the situation when parameters are not precisely known. Hence, the outcome is not precisely known either. Instead of maximizing the expected outcome, we maximized the probability of obtaining an outcome above a threshold of acceptability. We derived explicit analytical expressions for the optimal allocation and its associated probability, as a function of the threshold of acceptability, where the model parameters were distributed according to normal and uniform distributions. To illustrate our approach we revisited a previous study that incorporated cost-efficiency analyses in management decisions that were based on perturbation analyses of matrix population models. Incorporating derivations from this study into our framework, we extended the model to address potential uncertainties. We then applied these results to 2 case studies: management of a Koala (Phascolarctos cinereus) population and conservation of an olive ridley sea turtle (Lepidochelys olivacea) population. For low aspirations, that is, when the threshold of acceptability is relatively low, the optimal strategy was obtained by diversifying the allocation of funds. Conversely, for high aspirations, the budget was directed toward management actions with the highest potential effect on the population. The exact optimal allocation was sensitive to the choice of uncertainty model. Our results highlight the importance of accounting for uncertainty when making decisions and suggest that more effort should be placed on
Magin, Richard L.; Li, Weiguo; Velasco, M. Pilar; Trujillo, Juan; Reiter, David A.; Morgenstern, Ashley; Spencer, Richard G.
2011-01-01
We present a fractional-order extension of the Bloch equations to describe anomalous NMR relaxation phenomena (T1 and T2). The model has solutions in the form of Mittag-Leffler and stretched exponential functions that generalize conventional exponential relaxation. Such functions have been shown by others to be useful for describing dielectric and viscoelastic relaxation in complex, heterogeneous materials. Here, we apply these fractional-order T1 and T2 relaxation models to experiments performed at 9.4 and 11.7 Tesla on type I collagen gels, chondroitin sulfate mixtures, and to bovine nasal cartilage (BNC), a largely isotropic and homogeneous form of cartilage. The results show that the fractional-order analysis captures important features of NMR relaxation that are typically described by multi-exponential decay models. We find that the T2 relaxation of BNC can be described in a unique way by a single fractional-order parameter (α), in contrast to the lack of uniqueness of multi-exponential fits in the realistic setting of a finite signal-to-noise ratio. No anomalous behavior of T1 was observed in BNC. In the single-component gels, for T2 measurements, increasing the concentration of the largest components of cartilage matrix, collagen and chondroitin sulfate, results in a decrease in α, reflecting a more restricted aqueous environment. The quality of the curve fits obtained using Mittag-Leffler and stretched exponential functions are in some cases superior to those obtained using mono- and bi-exponential models. In both gels and BNC, α appears to account for microstructural complexity in the setting of an altered distribution of relaxation times. This work suggests the utility of fractional-order models to describe T2 NMR relaxation processes in biological tissues. PMID:21498095
Is it SUSY? -first steps after an LHC discovery
CERN. Geneva
2008-01-01
A missing energy discovery is possible at the LHC in the first year of running. The origin of such a signal could be any of a huge number of models of supersymmetry, or non-supersymmetric models with extra dimensions or "little Higgs". Recently we have developed a realistic strategy to rapidly narrow the list of candidate theories at, or close to, the moment of discovery. The strategy is based on robust ratios of inclusive counts of simple physics objects. We studied specific cases showing discrimination of look- alike models in simulated data sets that are at least 10 to 100 times smaller than used in previous studies. We discriminate supersymmetry models from non-supersymmetric look-alikes with only 100 pb-1 of simulated data, using combinations of observables that trace back to differences in spin.
New limits on the SUSY Higgs boson mass
Energy Technology Data Exchange (ETDEWEB)
Matchev, Konstantin T.; Pierce, Damien M.
1998-05-01
We present new upper limits on the light Higgs boson mass mh in supersymmetric models. We consider two gravity-mediated models (with and without universal scalar masses) and two gauge-mediated models (with a 5+5 or 10+10 messenger sector). We impose standard phenomenological constraints, as well as SU(5) Yukawa coupling unification. Requiring that the bottom and tau Yukawa couplings meet at the unification scale to within 15%, we find the upper limit mh<114 GeV in the universal supergravity model. This reverts to the usual upper bound of 125 GeV with a particular nonuniversality in the scalar spectrum. In the 5+5 gauge-mediated model we find mh<97 GeV for small tan beta and mh = 116 GeV for large tan beta, and in the 10+10 model we find mh<94 GeV. We discuss the implications for upcoming searches at LEP-II and the Tevatron.
[Effect of enamel matrix protein on periodontal cells in an in vitro wound healing model].
Yin, Yuan-zheng; Shen, Chi-jing; Song, Zhong-chen; Zhang, Xiu-li
2007-06-01
The aim of this study was to evaluate the influence of enamel matrix protein (EMP) on wound filling of periodontal ligament cells (PDLC) and gingival fibroblasts (GF), using an in vitro model of wound healing. In vitro wound models were mechanically created in subconfluent cultures of human GF and PDLC, by removing a 7mm wide band of the cell layer respectively. Wounded cultures were then incubated for a time periods up to 2,6,9 days in a media containing 10% fetal bovine serum (FBS), stimulated with EMP (100microg/ml) simultaneously, negative controls were those cultured only with media containing 10% FBS. Slides were fixed, stained with crystal violet and cell filling area within the wound boundaries was quantified by computer assisted histomorphometry. Statistical analysis was performed by SAS6.12 software package to determine the differences between the time points and groups. in the control group, there was difference between GF and PDLC in filling wound in vitro over 9 days of healing period. The difference was significant (P0.05) between the filling rate of two types of periodontal cells at the 6th, 9th day after wound creating. GF has a significantly greater ability to fill a wound than PDLC. However, EMP appears to exert an influence on cells that is compatible with improved wound healing, especially in that of PDLC.
Directory of Open Access Journals (Sweden)
Cotter Finbarr E
2009-08-01
Full Text Available Abstract Background Down syndrome (DS, caused by trisomy of human chromosome 21 (HSA21, is the most common genetic birth defect. Congenital heart defects (CHD are seen in 40% of DS children, and >50% of all atrioventricular canal defects in infancy are caused by trisomy 21, but the causative genes remain unknown. Results Here we show that aberrant adhesion and proliferation of DS cells can be reproduced using a transchromosomic model of DS (mouse fibroblasts bearing supernumerary HSA21. We also demonstrate a deacrease of cell migration in transchromosomic cells independently of their adhesion properties. We show that cell-autonomous proteome response to the presence of Collagen VI in extracellular matrix is strongly affected by trisomy 21. Conclusion This set of experiments establishes a new model system for genetic dissection of the specific HSA21 gene-overdose contributions to aberrant cell migration, adhesion, proliferation and specific proteome response to collagen VI, cellular phenotypes linked to the pathogenesis of CHD.
A Homeostatic Model of Neuronal Firing Governed by Feedback Signals from the Extracellular Matrix
Kazantsev, Victor; Gordleeva, Susan; Stasenko, Sergey; Dityatev, Alexander
2012-01-01
Molecules of the extracellular matrix (ECM) can modulate the efficacy of synaptic transmission and neuronal excitability. These mechanisms are crucial for the homeostatic regulation of neuronal firing over extended timescales. In this study, we introduce a simple mathematical model of neuronal spiking balanced by the influence of the ECM. We consider a neuron receiving random synaptic input in the form of Poisson spike trains and the ECM, which is modeled by a phenomenological variable involved in two feedback mechanisms. One feedback mechanism scales the values of the input synaptic conductance to compensate for changes in firing rate. The second feedback accounts for slow fluctuations of the excitation threshold and depends on the ECM concentration. We show that the ECM-mediated feedback acts as a robust mechanism to provide a homeostatic adjustment of the average firing rate. Interestingly, the activation of feedback mechanisms may lead to a bistability in which two different stable levels of average firing rates can coexist in a spiking network. We discuss the mechanisms of the bistability and how they may be related to memory function. PMID:22848555
A Simplified Matrix Formulation for Sensitivity Analysis of Hidden Markov Models
Directory of Open Access Journals (Sweden)
Seifemichael B. Amsalu
2017-08-01
Full Text Available In this paper, a new algorithm for sensitivity analysis of discrete hidden Markov models (HMMs is proposed. Sensitivity analysis is a general technique for investigating the robustness of the output of a system model. Sensitivity analysis of probabilistic networks has recently been studied extensively. This has resulted in the development of mathematical relations between a parameter and an output probability of interest and also methods for establishing the effects of parameter variations on decisions. Sensitivity analysis in HMMs has usually been performed by taking small perturbations in parameter values and re-computing the output probability of interest. As recent studies show, the sensitivity analysis of an HMM can be performed using a functional relationship that describes how an output probability varies as the network’s parameters of interest change. To derive this sensitivity function, existing Bayesian network algorithms have been employed for HMMs. These algorithms are computationally inefficient as the length of the observation sequence and the number of parameters increases. In this study, a simplified efficient matrix-based algorithm for computing the coefficients of the sensitivity function for all hidden states and all time steps is proposed and an example is presented.
Sgoldstino-less inflation and low energy SUSY breaking
Argurio, Riccardo; Coone, Dries; Heurtier, Lucien; Mariotti, Alberto
2017-07-01
We assess the range of validity of sgoldstino-less inflation in a scenario of low energy supersymmetry breaking. We first analyze the consistency conditions that an effective theory of the inflaton and goldstino superfields should satisfy in order to be faithfully described by a sgoldstino-less model. Enlarging the scope of previous studies, we investigate the case where the effective field theory cut-off, and hence also the sgoldstino mass, are inflaton-dependent. We then introduce a UV complete model where one can realize successfully sgoldstino-less inflation and gauge mediation of supersymmetry breaking, combining the α-attractor mechanism and a weakly coupled model of spontaneous breaking of supersymmetry. In this class of models we find that, given current limits on superpartner masses, the gravitino mass has a lower bound of the order of the MeV, i.e. we cannot reach very low supersymmetry breaking scales. On the plus side, we recognize that in this framework, one can derive the complete superpartner spectrum as well as compute inflation observables, the reheating temperature, and address the gravitino overabundance problem. We then show that further constraints come from collider results and inflation observables. Their non trivial interplay seems a staple feature of phenomenological studies of supersymmetric inflationary models.
A note on the Fisher information matrix for the skew-generalized-normal model
Arellano-Valle, Reinaldo B.
2013-01-01
In this paper, the exact form of the Fisher information matrix for the skew-generalized normal (SGN) distribution is determined. The existence of singularity problems of this matrix for the skewnormal and normal particular cases is investigated. Special attention is given to the asymptotic properties of the MLEs under the skew-normality hypothesis.
A note on the Fisher information matrix for the skew-generalized-normal model
Arellano-Valle, Reinaldo B.; Gómez, Héctor W.; Salinas, Hugo S.
2013-01-01
In this paper, the exact form of the Fisher information matrix for the skew-generalized normal (SGN) distribution is determined. The existence of singularity problems of this matrix for the skew-normal and normal particular cases is investigated. Special attention is given to the asymptotic properties of the MLEs under the skew-normality hypothesis. Peer Reviewed
Gradient System Modelling of Matrix Converters with Input and Output Filters
Jeltsema, Dimitri; Scherpen, Jacquelien M.A.; Klaassens, J. Ben
2003-01-01
Due to its complexity, the dynamics of matrix converters are usually neglected in controller design. However, increasing demands on reduced harmonic generation and higher bandwidths makes it necessary to study large-signal dynamics. A unified methodology that considers matrix converters, including
Life-Cycle Trade-Offs in Matrix Population-Models
Van Tienderen, P.H.
1995-01-01
Matrix projections allow identification of those phases in the life cycle with a high potential impact on the population growth rate. This impact is assessed by the sensitivity or elasticity of the matrix elements that are computed from life cycle data such as age-dependent survival or fecundity.
A light stop with flavor in natural SUSY
Auzzi, Roberto; Giveon, Amit; Gudnason, Sven Bjarke; Shacham, Tomer
2013-01-01
The discovery of a SM-like Higgs boson near 125 GeV and the flavor texture of the Standard Model motivate the investigation of supersymmetric quiver-like BSM extensions. We study the properties of such a minimal class of models which deals naturally with the SM parameters. Considering experimental bounds as well as constraints from flavor physics and Electro-Weak Precision Data, we find the following. In a self-contained minimal model — including the full dynamics of the Higgs sector — top squarks below a TeV are in tension with b → sγ constraints. Relaxing the assumption concerning the mass generation of the heavy Higgses, we find that a stop not far from half a TeV is allowed. The models have some unique properties, e.g. an enhancement of the h → boverline{b} , tau overline{tau} decays relative to the h → γγ one, a gluino about 3 times heavier than the stop, an inverted hierarchy of about 3 ÷ 20 between the squarks of the first two generations and the stop, relatively light Higgsino neutralino or stau NLSP, as well as heavy Higgses and a W ' which may be within reach of the LHC.
Ventral hernia repair using allogenic acellular dermal matrix in a swine model.
Silverman, R P; Li, E N; Holton, L H; Sawan, K T; Goldberg, N H
2004-12-01
This study was designed to assess the long-term efficacy of allogenic acellular dermal matrix (ADM) used as an interpositional graft for ventral hernia repair in a swine model. We created 12x4-cm full-thickness abdominal wall defects in 22 Yucatan miniature pigs. The defect was repaired with either two 6x4-cm pieces of AlloDerm (acellular dermal matrix processed from pig skin in order to avoid a xenogenic response, LifeCell Corporation, Branchburg, NJ USA) (n = 12), or expanded polytetrafluoroethylene mesh (ePTFE) (Gore-Tex, W.L. Gore & Associates, Inc., Newark, DE USA) (n = 10). In six pigs, a separate 3-cm fascial incision was made, which was then suture repaired as a control for tensiometry testing. The surgical sites were evaluated at either 3 months or 9 months for the presence of a hernia, stretching of the implant, adhesions, vascularity, and biomechanical strength. Two hernias occurred in both the ADM and the ePTFE groups. There was minimal stretching of the implants and minimal adhesions in both groups. Fluorescein testing and histology indicated vascular ingrowth into the ADM. There was no statistical difference between the mean breaking strengths of the ADM-fascial interface (106.5 N +/- SD 40.1), the interface between two pieces of ADM (149.1 N +/- SD 76.7), and the primary fascial repair (108.1 N +/- SD 20.9) at 9 months. The ADM-fascial interface had a significantly higher breaking strength than that of the ePTFE-fascia interface (66.1 N +/- SD 30.1) (P = 0.017, t-test, P = 0.043 Wilcoxon rank sum test). In this study, we were unable to demonstrate a difference between ADM and ePTFE in their ability to repair ventral hernias at 9 months in a swine model. The ADM additionally supports vascular ingrowth and exhibits increased breaking strength at the fascia-implant interface.
Influence of PEGylation on nanoparticle mobility in different models of the extracellular matrix.
Tomasetti, Luise; Liebl, Renate; Wastl, Daniel S; Breunig, Miriam
2016-11-01
Nanoparticle transport inside the extracellular matrix (ECM) is a crucial factor affecting the therapeutic success. In this work, two in vitro ECM models - a neutrally charged collagen I network with an effective pore size of 0.47μm and Matrigel, a basement membrane matrix with strong negative charge and effective pore size of 0.14μm - were assessed for barrier function in the context of diffusing nanoparticles. Nanoparticles with a size of 120nm were coated with poly(ethylene glycol) (PEG) of different molecular weights - 2, 5 and 20kDa - over a range of gradually increasing coating densities - precisely 0.2, 2, 8 and 20PEG/nm2. The PEG corona was imaged in its native state without any drying process by atomic force microscopy, revealing that the experimentally determined arrangement of PEG at the surface did not match with what was theoretically expected. In a systematic investigation of nanoparticle mobility via fluorescence recovery after photobleaching, increasing both PEG MW and PEGylation density gradually improved diffusion properties predominately in collagen. Due to its smaller pore size and electrostatic obstruction, diffusion coefficients were about ten times lower in Matrigel than in the collagen network and an extension of the PEG MW and density did not necessarily lead to better diffusing particles. Consequently, collagen gels were revealed to be a poor model for nanoparticle mobility assessment, as neither their pore size nor their electrostatic properties reflect the expected in vivo conditions. In Matrigel, diffusion proceeded according to a sigmoidal increase with gradually increasing PEG densities showing threshold zeta potentials of 11.6mV (PEG2kDa) and 13.8mV (PEG5kDa), below which particles were regarded as mobile. Irrespective of the molecular weight particles with a PEGylation density lower than 2PEG/nm2 were defined as immobile and those with a PEG coverage of more than 8PEG/nm2 as mobile. Copyright © 2016 Elsevier B.V. All rights
Rencontres de Moriond QCD 2012: Searches for Dark Matter, SUSY and other exotic particles
CERN Bulletin
2012-01-01
The fact that SUSY and other new physics signals do not seem to hide in “obvious” places is bringing a healthy excitement to Moriond. Yesterday’s presentations confirmed that, with the 2012 LHC data, experiments will concentrate on searches for exotic particles that might decay into yet unexplored modes. In the meantime, they are setting unprecedented boundaries to regions where new particles (not just SUSY) could exist. The limits of what particle accelerators can bring to enlighten the mystery of Dark Matter were also presented and discussed. Each bar on the picture represents a decay channel that the ATLAS Collaboration (top) and the CMS Collaborations (bottom) have analysed. The value indicated on the scale (or on the relevant bar) defines the maximum mass that the particle in that search cannot have. Not knowing what kind of new physics we should really expect, and given the fact that it does not seem to be hiding in any of the obvious places, e...
van Deel, Elza D; Najafi, Aref; Fontoura, Dulce; Valent, Erik; Goebel, Max; Kardux, Kim; Falcão-Pires, Inês; van der Velden, Jolanda
2017-07-15
This paper describes a novel model that allows exploration of matrix-induced cardiomyocyte adaptations independent of the passive effect of matrix rigidity on cardiomyocyte function. Detachment of adult cardiomyocytes from the matrix enables the study of matrix effects on cell shortening, Ca(2+) handling and myofilament function. Cell shortening and Ca(2+) handling are altered in cardiomyocytes cultured for 24 h on a stiff matrix. Matrix stiffness-impaired cardiomyocyte contractility is reversed upon normalization of extracellular stiffness. Matrix stiffness-induced reduction in unloaded shortening is more pronounced in cardiomyocytes isolated from obese ZSF1 rats with heart failure with preserved ejection fraction compared to lean ZSF1 rats. Extracellular matrix (ECM) stiffening is a key element of cardiac disease. Increased rigidity of the ECM passively inhibits cardiac contraction, but if and how matrix stiffening also actively alters cardiomyocyte contractility is incompletely understood. In vitro models designed to study cardiomyocyte-matrix interaction lack the possibility to separate passive inhibition by a stiff matrix from active matrix-induced alterations of cardiomyocyte properties. Here we introduce a novel experimental model that allows exploration of cardiomyocyte functional alterations in response to matrix stiffening. Adult rat cardiomyocytes were cultured for 24 h on matrices of tuneable stiffness representing the healthy and the diseased heart and detached from their matrix before functional measurements. We demonstrate that matrix stiffening, independent of passive inhibition, reduces cell shortening and Ca(2+) handling but does not alter myofilament-generated force. Additionally, detachment of adult cultured cardiomyocytes allowed the transfer of cells from one matrix to another. This revealed that stiffness-induced cardiomyocyte changes are reversed when matrix stiffness is normalized. These matrix stiffness-induced changes in cardiomyocyte
Non-SUSY BSM Searches: Recent Results from ATLAS & CMS
Malek, Fairouz; The ATLAS collaboration
2015-01-01
The Standard Model of particle physics is a sensational success, especially since the discovery the 125 GeV Higgs boson. However, there are still numerous unanswered questions… Why is the Higgs so light? Do the interactions couplings unify and how can gravity be included? Why three fermion generations? What is dark matter? Theories Beyond the Standard Model (BSM), such as Grand Unified Theories, Extra Dimensions or Technicolour are trying to answer these questions. In this talk, we will focus on the most recent results obtained by the ATLAS and CMS experiments at the LHC for BSM searches, excluding Higgs and supersymmetry searches. New results in Dark matter, heavy narrow bosons, new heavy quarks and 3rd generation lepto-quarks will be presented. A brief summary of the perspectives at 14 Tev and at HL-LHC will be shown.
Li, Victor C.; Wang, Youjiang; Backer, Stanley
A MICROMECHANICAL model has been formulated for the post-cracking behavior of a brittle matrix composite reinforced with randomly distributed short fibers. This model incorporates the mechanics of pull-out of fibers which are inclined at an angle to the matrix crack plane and which undergo slip-weakening or slip-hardening during the pull-out process. In addition, the random location and orientation of fibers are accounted for. Comparisons of model predictions of post-cracking tension-softening behavior with experimental data appear to support the validity of the model. The model is used to examine the effects of fiber length, snubbing friction coefficient and interfacial bond behavior on composite post-cracking tensile properties. The scaling of the bridging fracture toughening with material parameters is discussed.
Directory of Open Access Journals (Sweden)
Omid Massah
2017-09-01
Discussion: The results indicated that the Matrix Model is effective for treating MA dependence. However, the long length of the treatment, lack of cost-effectiveness, and intensive staff training are significant problems associated with providing MA treatment. Further studies are suggested to evaluate the role of brief interventions in reducing these problems in methadone treatment services.
Distributed SUSY breaking: dark energy, Newton's law and the LHC
Burgess, C. P.; van Nierop, L.; Williams, M.
2014-07-01
We identify the underlying symmetry mechanism that suppresses the low-energy effective 4D cosmological constant within some 6D supergravity models, generically leading to results suppressed by powers of the KK scale, m {/K K 2}, relative to the much larger size, m 4, associated with mass- m particles localized in these models on codimension-2 branes. These models are examples for which the local conditions for unbroken supersymmetry can be satisfied locally everywhere within the extra dimensions, but are obstructed only by global conditions like flux quantization or by the mutual inconsistency of the boundary conditions required at the various branes. Consequently quantities (like vacuum energies) forbidden by supersymmetry cannot become nonzero until wavelengths of order the KK scale are integrated out, since only such long wavelength modes can see the entire space and so `know' that supersymmetry has broken. We verify these arguments by extending earlier rugby-ball calculations of one-loop vacuum energies within these models to more general pairs of branes within two warped extra dimensions. For the Standard Model confined to one of two otherwise identical branes, the predicted effective 4D vacuum energy density is of order ρ vac ⋍ C( mM g /4 πM p )4 = C(5 .6 × 10-5 eV)4, where M g ≳ 10 TeV (corresponding to extra-dimensional size r ≲ 1 μm) and M p = 2 .44 × 1018 GeV are the 6D and 4D rationalized Planck scales, and m is the heaviest brane-localized particle. (For numerical purposes we take m to be the top-quark mass and take M g as small as possible, consistent with energy-loss bounds from supernovae.) C is a constant depending on the details of the bulk spectrum, which could easily be of order 500 for each of hundreds of fields in the bulk. The value C ˜ 6 × 106 would give the observed Dark Energy density.
Strong Production SUSY Searches at ATLAS and CMS
Marshall, Z L
2015-01-01
The results of searches for strongly-produced supersymmetry at the Large Hadron Collider by the ATLAS and CMS collaborations are presented. Several of the historically strongest zero-and one-lepton final state searches have been updated to include multi-bin fits and combinations. In addition, new two-lepton final state search results are shown from CMS and ATLAS, which show 2.6 and 3.0 standard deviation excesses, respectively, above the standard model expectation, albeit in different regions of phase space. Both collaborations have also shown new searches that cover areas uncovered by previous searches, in both searches for light stops and searches for stealth supersymmetry.
Overview of SUSY results from the ATLAS experiment
Brazzale, S; The ATLAS collaboration
2014-01-01
The search for Supersymmetry remains a hot topic in high energy phisycs in the light of the discovery of the Higgs boson at a mass of 125 GeV. Supersymmetry cancels out the quadratically divergent quantum corrections on the Higgs boson mass and provides a particle which can explain the presence of Dark Matter in the Universe. Moreover, it unifies the gauge couplings of the Standard Model at high energy scales. Under certain theoretical assumptions, some of the supersymmetric particles are preferred to be lighter than TeV and their discovery can thus be accessible at the LHC. The recent results from searches for Supersymmetry with\
Recent Results on SUSY and Exotica Searches at the LHC
Directory of Open Access Journals (Sweden)
Grout Zara
2015-01-01
Full Text Available A review is presented of searches for Beyond the Standard Model (BSM physics at the ATLAS and CMS experiments at the Large Hadron Collider (LHC with emphasis on most recent results. This includes a summary of Supersymmetry searches covering strong, electroweak, and R-parity violating scenarios, and a range of exotica searches including heavy boson searches, extra dimensions, and long-lived particles. The status of BSM physics after the first data-taking period (Run 1 of the LHC and the prospects for the second data-taking period (Run 2, beginning in 2015, are discussed.
DEFF Research Database (Denmark)
Lee, Kyo-Beum; Blaabjerg, Frede
2004-01-01
This paper presents a new sensorless vector control system for high performance induction motor drives fed by a matrix converter with non-linearity compensation. The nonlinear voltage distortion that is caused by commutation delay and on-state voltage drop in switching device is corrected by a new...... matrix converter model. Regulated Order Extended Luenberger Observer (ROELO) is employed to bring better response in the whole speed operation range and a method to select the observer gain is presented. Experimental results are shown to illustrate the performance of the proposed system...
DEFF Research Database (Denmark)
Lee, Kyo-Beum; Blaabjerg, Frede
2004-01-01
This paper presents a new sensorless vector control system for high performance induction motor drives fed by a matrix converter with a non-linearity compensation and disturbance observer. The nonlinear voltage distortion that is caused by communication delay and on-state voltage drop in switching...... device is corrected by a new matrix converter modeling. The lumped disturbances such as parameter variation and load disturbance of the system are estimated by the radial basis function network (RBFN). An adaptive observer is also employed to bring better responses at the low speed operation...
Characterization of metal matrix composites by linear ultrasonics and finite element modeling.
Chen, Xuesheng; Sharples, Steve D; Clark, Matt; Wright, David
2013-02-01
Titanium metal matrix composites (TiMMCs) offer advantages over traditional materials for aerospace applications due to the increased mechanical strength of the materials. But the non-destructive inspection of these materials, especially with ultrasound, is in an infancy stage. If the manufacturing process of TiMMC is not correctly controlled, then disbonds and voids between the fibers can result. The effective microstructure of the composite makes difficulty to interpret results from traditional ultrasound techniques because of the scattering caused by fibers; the scattering prevents the ultrasound from penetrating far into the composite region and produces a background signal masking any reflections from voids. In this paper, relatively low frequency ultrasound is used to probe the composite region, and the state of the composite (porosity) is inferred from the velocity of the ultrasound traversing the composite. The relationship between the velocity and porosity is complex in this regime, so finite element (FE) analysis is used to model the composite regions and relate the velocity to the porosity. The FE simulated results are validated by ultrasound velocity measurements.
Mais, Laís Amaral; Domene, Semíramis Martins Álvares; Barbosa, Marina Borelli; Taddei, José Augusto de Aguiar Carrazedo
2014-01-01
Timely and appropriate complementary feeding is essential for the healthy growth and development of children, and Primary Health Care, especially the Family Health Support Nuclei, are the ideal location for developing relevant actions during this period. A cross-sectional study that applied a questionnaire to mothers and anthropometric evaluation for 324 children sought to develop an index of complementary feeding inadequacies and to study its association with social, economic, clinical, epidemiological and nutritional variables. For quantification of feeding inadequacies, an index using the Delphi method was created. High frequencies were observed for all inadequacies, especially for late introduction of solids (80.2%), early introduction of sugar/thickeners (78.1%) and liquids (73.5%). The most significant results of these associations were early weaning of exclusive (p = 0.000) and total (p = 0.005) breastfeeding, absence of partner (p = 0.001) and the mother supporting the family financially (p = 0.025). The use of this index identifies higher-risk situations for developing a nutritional assistance action plan, especially when it comes to promoting matrix model work.
Data model for the elimination of matrix effects in enzyme-based flow-injection systems.
Becker, T M; Schmidt, H L
2000-08-20
This contribution presents a new conceptional enzyme-based flow injection analysis (FIA) system for the process and quality control of food processing and biotechnological systems. It provides the determination of different analytes in distinct process media on the base of a common experimental set-up. In contrast to known comparable systems, analysis is performed without the commonly used sample preparation and dilution steps. Instead, the adaptation to the necessary measurement range is realized by optimization of intrinsic system parameters. The central principle of the work presented is the elimination of occurring interferences by the heterogeneous matrix of the process sample. Based on a particular injection mode, the application of dehydrogenases as indicator enzymes and a specially developed data model using cognitive methods, cross sensitivities of the detector as well as disturbed reaction rates of the enzymes could be almost completely compensated. Two applications are presented, the analysis of ethanol in non-alcoholic beer and the online determination of D-/L-lactate during a lactic acid fermentation, which reveal the advantage of the developed system. Copyright 2000 John Wiley & Sons, Inc.
Fahmi, A. K.; Hasanah, L.; Rusdiana, D.; Aminudin, A.; Suhendi, E.
2017-03-01
The tunneling current of n-p-n bipolar junction transistor AGNR-based is modeled with semi-numerical method. The exponential solution from Schrödinger equation is used and solved analytically. The potential profile of n-p-n BJT divided into several segments in the numerical method. Then, the solved analytical result is used in the numerical method to compute the electron transmittance. Transfer Matrix Method (TMM) is the numerical method used to compute the electron transmittance. From the calculated transmittance the tunneling current can be computed by using Landauer formula with aid of Gauss-Legendre Quadrature (GLQ). Next, the tunneling current is computed with several change of variables which are base-emitter voltage (VBE), base-collector voltage (VBC), temperature and the AGNR’s width. The computed tunneling current shows that the larger value of applied voltage for both VBE and VBC results in larger value of tunneling current. At the lower temperature, the current is larger. The computed tunneling current shows that at wider width of AGNR, the current is also larger. This is due to the decreased band-gap energy (Eg) because of the wider width of AGNR.
Xu, Guang-Kui; Yang, Chun; Du, Jing; Feng, Xi-Qiao
2014-04-11
Cells sense and respond to the elasticity of extracellular matrix (ECM) via integrin-mediated adhesion. As a class of well-documented mechanosenors in cells, integrins switch among inactive, bound, and dissociated states, depending upon the variation of forces acting on them. However, it remains unclear how the ECM elasticity directs and affects the states of integrins and, in turn, their cellular functions. On the basis of our recent experiments, a biomechanical model is proposed to reveal the role of ECM elasticity in the state-switching of integrins. It is demonstrated that a soft ECM can increase the activation level of integrins while a stiff ECM has a tendency to prevent the dissociation and internalization of bound integrins. In addition, it is found that more stable focal adhesions can form on stiffer and thinner ECMs. The theoretical results agree well with relevant experiments and shed light on the ECM elasticity-sensing mechanisms of cells. Copyright © 2014 Elsevier Ltd. All rights reserved.
Directory of Open Access Journals (Sweden)
T.V. Bershova
2009-01-01
Full Text Available Restrictive cardiomyopathy (RCMP is heart disorder with unclear etiology; it can be characterized as disease with disorder of diastolic myocardium function of left ventricle, conditioned by restriction. The chronic heart failure as a syndrome of RCMP can develop as a result of disbalance in system of complex biochemical, structural, and geometrical mechanisms of myocardium re-modeling. Extra cellular matrix play significant role in heart structure and geometry breaking. The destruction of heart is realized by matrix metalloproteinases (MMP. The activity of MMP, in its turn, is controlled by its tissue inhibitors. The present study analyzed the role of MMP in process of collagen’s synthesis and catabolism deregulation, myocardium fibrosis, change of heart chambers, and development of diastolic dysfunction in children with RCMP.Key words: children, chronic heart failure, restrictive cardiomyopathy, matrix metalloproteinases.(Voprosy sovremennoi pediatrii — Current Pediatrics. 2009;8(5:36-39
Directory of Open Access Journals (Sweden)
M. Lukšič
2013-01-01
Full Text Available We compared the results of the Madden-Glandt (MG integral equation approximation for partly-quenched systems with the commonly accepted formalism of Given and Stell (GS. A studied system was a +1:-1 restricted primitive model (RPM electrolyte confined in a quenched +1:-1 RPM matrix. A renormalization scheme was proposed for the set of MG replica Ornstein-Zernike equations. Long-ranged direct and total correlation functions, describing the interactions between the annealed electrolyte species within the same replicas and between the annealed and matrix particles, appeared to be the same for MG and GS approach. Both versions of the theory give very similar results for the structure and thermodynamics of an annealed subsystem. Differences between excess internal energy, excess chemical potential, and isothermal compressibility become pronounced only at high concentrations of matrix particles.
Merlé, Y; Tod, M
2001-08-01
Influence of experimental design on hyperparameter estimates precision when performing a population pharmacokinetic-pharmacodynamic (PK-PD) analysis has been shown by several studies and various approaches have been proposed for optimizing or evaluating such designs. Some of these methods rely on the optimization of a suitable scalar function of the population information matrix. Unfortunately for the nonlinear models encountered in pharmacokinetics or pharmacodynamics the latter is particularly difficult to evaluate. Under some assumptions and after a linearization of the PK-PD model a closed form of this matrix can be obtained which considerably simplifies its calculation but leads to an approximation. The aim of this paper is to evaluate the quality of the latter and its potential impact, when comparing or optimizing population designs and to relate it to Bates and Watts curvature measures. Two models commonly used in PK-PD were considered and nominal hyperparameter values when chosen for each one. Several population designs were studied and the associated population information matrix was computed for each using the approximate procedure and also using a reference method. Design optimizations were calculated under constraints for each model from the reference and approximate population information matrix. Nonlinearity curvatures were also computed for every model and design. The impact of model linearization when calculating the population information matrix was then examined in terms of lower bound accuracies on the hyperparameter estimates, design criterion variation, as well as D-optimal population designs, these results being related to nonlinearity curvature measures. Our results emphasize the influence of the parameter effects curvature when deriving the lower bounds of the hyperparameter estimates precision for a given design from the approximate population information matrix especially for hyperparameters quantifying the PK-PD interindividual