cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
An incompressible polymer fluid interacting with a Koiter shell
Creators: name: Breit, Dominic
name: Mensah, Prince Romeo
Publisher: name: arXiv
Year: 2020
Subjects: subject: Analysis of PDEs (math.AP)
subject: FOS: Mathematics

description: We study a mutually coupled mesoscopic-macroscopic-shell system of equations modeling a dilute incompressible polymer fluid which is evolving and interacting with a flexible shell of Koiter type. The polymer constitutes a solvent-solute mixture where the solvent is modelled on the macroscopic scale by the incompressible Navier-Stokes equation and the solute is modelled on the mesoscopic scale by a Fokker-Planck equation (Kolmogorov forward equation) for the probability density function of the bead-spring polymer chain configuration. This mixture interacts with a nonlinear elastic shell which serves as a moving boundary of the physical spatial domain of the polymer fluid. We use the classical model by Koiter to describe the shell movement which yields a fully nonlinear fourth order hyperbolic equation. Our main result is the existence of a weak solution to the underlying system which exists until the Koiter energy degenerates or the flexible shell approaches a self-intersection.
description: 38 pages
Results of the ROTOR-program. II. The long-term photometric variability of weak-line T Tauri stars
Creators: name: Grankin, K. N.
name: Bouvier, J.
name: Herbst, W.
name: Melnikov, S. Yu.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: T Tauri stars exhibit variability on all timescales, whose origin is still debated. On WTTS the variability is fairly simple and attributed to long-lived, ubiquitous cool spots. We investigate the long term variability of WTTS, extending up to 20 years in some cases, characterize it statistically and discuss its implications for our understanding of these stars. We have obtained a unique, homogeneous database of photometric measurements for WTTS extending up to 20 years. It contains more than 9 000 UBV R observations of 48 WTTS. All the data were collected at Mount Maidanak Observatory (Uzbekistan) and they constitute the longest homogeneous record of accurate WTTS photometry ever assembled. Definitive rotation periods for 35 of the 48 stars are obtained. Phased light curves over 5 to 20 seasons are now available for analysis. Light curve shapes, amplitudes and colour variations are obtained for this sample and various behaviors exhibited, discussed and interpreted. Our main conclusion is that most WTTS have very stable long term variability with relatively small changes of amplitude or mean light level. The long term variability seen reflects modulation in the cold spot distributions. Photometric periods are stable over many years, and the phase of minimum light can be stable as well for several years. On the long term, spot properties do change in subtle ways, leading to secular variations in the shape and amplitudes of the light curves.
Galactic model parameters for field giants separated from field dwarfs by their 2MASS and V apparent magnitudes
Creators: name: Bilir, S.
name: Karaali, S.
name: Guver, T.
name: Karatas, Y.
name: Ak, S. G.
Publisher: name: arXiv
Year: 2005
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We present a procedure which separates field dwarfs and field giants by their 2MASS and V apparent magnitudes. The procedure is based on the spectroscopically selected standards, hence it is confident. We applied this procedure to stars in two fields, SA 54 and SA 82, and we estimated a full set of Galactic model parameters for giants including their total local space density. Our results are in agreement with the ones appeared recently in the literature.
description: 10 pages, 4 figures and 5 tables, accepted for publication in AN
Transcription of the narration of Reel #4 (collection LA 256)
Creators: name: Parker, Verdena
name: Spence, Justin
Publisher: name: California Language Archive, University of California, Berkeley
Year: 2020
Subjects: subject: hup

description: Audio file VP-160717-05: transcription of VP-190317-05 (narration of Reel #4 from the LA 256 collection at SCOIL, one of six reels of 8mm film created by Verdena in the 1960s, featuring scenes of everyday life around Hoopa Valley as well as Brush Dances), from 12:12 to 15:12. Due to re-numbering, Reel #4 has been assigned the CLA item number LA 256.043.
Shadowed triplet pairings in Hund's metals with spin-orbit coupling
Creators: name: Clepkens, Jonathan
name: Lindquist, Austin W.
name: Kee, Hae-Young
Publisher: name: arXiv
Year: 2020
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: Hund's coupling in multiorbital systems allows for the possibility of even-parity orbital-antisymmetric spin-triplet pairing, which can be stabilized by spin-orbit coupling (SOC). While this pairing expressed in the orbital basis is uniform and spin-triplet, it appears in the band basis as a pseudospin-singlet, with the momentum dependence determined by the SOC and the underlying triplet character remaining in the form of interband pairing active away from the Fermi energy. Here, we examine the role of momentum-dependent SOC in generating nontrivial pairing symmetries, as well as the hidden triplet nature associated with this interorbital pairing, which we dub a "shadowed triplet". Applying this concept to Sr$_{2}$RuO$_{4}$, we first derive several forms of SOC with $d$-wave form factors from a microscopic model, and subsequently we show that for a range of SOC parameters, a pairing state with $s+id_{xy}$ symmetry can be stabilized. Such a pairing state is distinct from pure spin-singlet and -triplet pairings due to its unique character of pseudospin-energy locking. We discuss experimental probes to differentiate the shadowed triplet pairing from conventional pseudospin-triplet and -singlet pairings.
description: 12 pages, 5 figures
Baseline acid rock drainage potential study on the Eskay Creek mill tailings
Creators: name: Dai, Ning
Publisher: name: University of British Columbia
Year: 2009

description: The Eskay Creek Mine, owned by Prime Resources Group Inc. is located about 80 kilometres north of Stewart, British Columbia. The mine is an unusual polymetallic, precious-metal rich volcanogenic massive sulfide and sulfosalt deposit which has generated much interest over the paste decade. The Eskay Creek Mine is one of the highest grades gold and silver deposits in the world The objective of this study is to conduct a base line study on the potential for ARD generation from the two types of mill tailings derived from two different ore zones (109 zone and N EX zone) at the Eskay Creek Mine in order to assess the maximum possible ARD potential under the worst disposal conditions among the several tailings disposal options. The study involved Sobek ABA tests, Modified ABA tests, shake flask tests and kinetic tests. The results from ABA tests show that the acid potential is much higher than the neutralization potential in both 109 and N EX tailings. This means that both 109 and N EX tailings have the probability for acid generation. Shake Flask test results show that generation of ARD from both tailings is likely and temperature is an important factor in acid generation. Submarine tailings disposal may be the best way to dispose tailings materials in Eskay Creek Mine.
Microwave apparatus for gravitational waves observation
Creators: name: Ballantini, R.
name: Bernard, Ph.
name: Calatroni, S.
name: Chiaveri, E.
name: Chincarini, A.
name: Croce, R. P.
name: Cuneo, S.
name: Galdi, V.
name: Gemme, G.
name: Losito, R.
name: Parodi, R.
name: Picasso, E.
name: Pierro, V.
name: Pinto, I. M.
name: Podesta', A.
name: Vaccarone, R.
Publisher: name: arXiv
Year: 2005
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: In this report the theoretical and experimental activities for the development of superconducting microwave cavities for the detection of gravitational waves are presented.
description: 42 pages, 28 figures
EX-ANTE EVALUATION OF AGRI-ENVIRONMENTAL SCHEMES: COMBINING ELEMENTS OF PRIVATE AND PUBLIC DECISION MAKING
Creators: name: Bartolini, Fabio
name: Gallerani, Vittorio
name: Viaggi, Davide
name: Bartolini, Fabio
name: Gallerani, Vittorio
name: Viaggi, Davide
Publisher: name: Unknown
Year: 2008
Subjects: subject: Agricultural and Food Policy
subject: Environmental Economics and Policy
subject: Risk and Uncertainty
subject: Agri-environmental schemes
subject: Real Options
subject: Investments
subject: Decoupled payments
subject: Uncertainty

description: The objective of this paper is to set a complete ex-ante evaluation to support Decision Makers in designing more efficient and effective agri-environmental contracts, through an integrated modelling of elements of private and public decision making. Ex-ante comparison of policy design options in terms of overall effectiveness requires both simulations of farmers' behaviour and evaluation of the farms simulations outcomes. An intermediate step is the aggregation of single farms impacts at territorial level, in order to identify the aggregate impact of each alternative. Alternatives are several contract design, based on different levels of payments. Farm level analysis is based on a real options approach including in the simulations the timing of choice and the uncertainty in the future about price and decoupled payments. Aggregate policy impact is identified through the quantification of economic, social and environmental impacts at territorial level and the weights are elicited with Multiple-Criteria Robust Interactive Decision Analysis (MCRID). Simulations in the case study show that relevant opportunities to improve policy design are available. Multicriteria Analysis is then used to aggregate impacts of many criteria, including not only effects on the environment, but also economic and social impacts.
Flexible quota constraints in positive mathematical programming models
Creators: name: Buysse, Jeroen
name: Van Der Straeten, Bart
name: Claeys, Dakerlia
name: Lauwers, Ludwig H.
name: Marchand, Fleur L.
name: Van Huylenbroeck, Guido
name: Buysse, Jeroen
name: Van Der Straeten, Bart
name: Claeys, Dakerlia
name: Lauwers, Ludwig H.
name: Marchand, Fleur L.
name: Van Huylenbroeck, Guido
Publisher: name: Unknown
Year: 2008
Subjects: subject: Agricultural and Food Policy
subject: Demand and Price Analysis
subject: Research Methods/ Statistical Methods
subject: Quota
subject: flexibility
subject: Positive Mathematical Programming
subject: farm model
subject: Common Agricultural Policy

description: To explain over- and underuse of available quota, Buysse et al. (2007) have integrated the shadow cost of the quota constraint in a quota flexibility function in a positive mathematical programming model. This method and central hypothesis, formulated and tested for the case of Belgian sugar beet farms, is in current paper extended and confirmed for the cases of Flemish dairy quota and manure emission rights. Despite the different organisation, objectives and implementations of the diverse quota systems, the results are similar. A higher utilisation of quota is significantly driven by the quota rent, but farm characteristics are also important and the effect declines with increasing quota rent. Regardless the quota, the dairy quota flexibility behaviour of the sample of Flemish farms results in an output price elasticity of 0.6%. The quota flexibility functions can be used for policy analysis, model sophistication and farm advisory instrument.
MODELLING FARMS' PRODUCTION DECISIONS UNDER EXPENDITURE CONSTRAINTS
Creators: name: Bokusheva, Raushan
name: Kumbhakar, Subal C.
name: Bokusheva, Raushan
name: Kumbhakar, Subal C.
Publisher: name: Unknown
Year: 2008
Subjects: subject: Farm Management
subject: Research Methods/ Statistical Methods
subject: Indirect production function
subject: SFA
subject: expenditure constraints
subject: technical efficiency
subject: Russian agriculture

description: Limited budget for the purchase of variable inputs might adversely affect producer's input use decisions and might result in a non-optimal input usage. If expenditure constrains are present and binding, unconstrained profit-maximization is not valid for modelling producers' input use decisions. In this paper we apply the indirect production function approach which describes output maximization subject to a given technology, a set of quasi-fixed inputs and a given budget for the purchase of variable inputs. By employing the indirect production function in the stochastic frontier framework we can estimate producer's output loss due to both expenditure constraints and technical inefficiency. Our estimation results show that most of the study farms were expenditure constrained during the considered period. Expenditure constraints have caused on average a potential output loss of 11 percent. Output loss due to technical inefficiency is quite moderate and averages 18 percent.
Time is Money: Optimal Investment Delay in Procurement (and Concession) Contracts
Creators: name: D'Alpaos, Chiara
name: Moretto, Michele
name: Valbonesi, Paola
name: D'Alpaos, Chiara
name: Moretto, Michele
name: Valbonesi, Paola
Publisher: name: Unknown
Year: 2006
Subjects: subject: Public Economics
subject: procurement/concession contracts
subject: premium/penalty fee
subject: investment timing flexibility

description: Procurement (and concession) contracts are agreements granting the right to construct public works, operate and provide a service/good. The main advantage of a procurement contract is that it passes full responsibility for investment and operations to the private sector and consequently provides incentives for efficiency. Although most contracts include penalty/premium clauses to avoid construction risks (i.e. delays), evidence from ongoing procurement contracts shows that there are many delays in making investments. Actually these clauses introduce the flexibility to decide when it is optimal to invest and consequently increase the contract’s value for the contractor. Therefore if the contracting authority underestimates penalty/premium fees, these may be totally ineffective in avoiding construction risks. In this paper we specifically investigate the effects that penalty/premium clauses have on both contract value and reduction of delay. We also focus on the design of optimal penalty/premium rules.
Household Food Expenditures Across Income Groups: Do Poor Households Spend Differently than Rich Ones?
Creators: name: Damon, Amy L.
name: King, Robert P.
name: Leibtag, Ephraim S.
name: Damon, Amy L.
name: King, Robert P.
name: Leibtag, Ephraim S.
Publisher: name: Unknown
Year: 2006
Subjects: Food Consumption/Nutrition/Food Safety

description: The Life Cycle - Permanent Income Hypotheses (LCPIH) suggests that the timing of an income payment or government transfer should have no effect on the expenditures of the recipient. In this paper we test the LCPIH against a dynamic model of household consumption which predicts clustered food expenditure. We use data from 7,013 households in fifty-two urban and peri-urban markets throughout the United States containing detailed daily expenditure data collected by ACNielsen Homescan for 2003. Specifically, we examine aggregate food expenditure patterns, shopping trip patterns, and expenditure patterns across retail channels over calendar weeks, weekly seven day cycles, and days of the week. Our main finding is that households in the lowest 25 percent of the income distribution that have zero employed people have a significantly higher differenced expenditure level in the beginning of the month and significantly lower differenced expenditure in the last week or weeks of the calendar month, thus rejecting the LCPIH. Further, we find that, in general, households do not use convenience stores as a complementary retail channel to the grocery channel.
The Influence of Dust Formation Modelling on Na I and K I Line Profiles in Substellar Atmospheres
Creators: name: Johnas, C. M. S.
name: Helling, Ch.
name: Dehn, M.
name: Woitke, P.
name: Hauschildt, P. H.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We aim to understand the correlation between cloud formation and alkali line formation in substellar atmospheres.We perform line profile calculations for Na I and K I based on the coupling of our kinetic model for the formation and composition of dust grains with 1D radiative transfer calculations in atmosphere models for brown dwarfs and giant gas planets. The Na I and K I line profiles sensibly depend on the way clouds are treated in substellar atmosphere simulations. The kinetic dust formation model results in the highest pseudo-continuum compared to the limiting cases.
description: 5 pages, Accepted for publication in MNRAS
The Impact of Eyeglasses on the Academic Performance of Primary School Students: Evidence from a Randomized Trial in Rural China
Creators: name: Glewwe, Paul
name: Park, Albert
name: Zhao, Meng
name: Glewwe, Paul
name: Park, Albert
name: Zhao, Meng
Publisher: name: Unknown
Year: 2006
Subjects: International Development
Teaching/Communication/Extension/Profession

description: About 10% of primary school students in developing countries have poor vision, yet in virtually all of these countries very few children wear glasses. There has been almost no research on the impact of poor vision on school performance in developing countries, and simple OLS estimates are likely to be biased because students who study more often are likely to develop poor vision faster. This paper presents results from the first year of a randomized trial in Western China that began in the summer of 2004. The trial involves over 19,000 students in 165 schools in two counties of Gansu province. The schools were randomly divided (at the township level) into 103 schools that received eyeglasses (for students in grades 3-5) and 62 schools that served as controls. The results from the first year indicate that, after one year, provision of eyeglasses increased test scores by 0.15 to 0.30 standard deviations (of the distribution of the test scores).
Dynamics and thermodynamics of axisymmetric flows: I. Theory
Creators: name: Leprovost, Nicolas
name: Dubrulle, Bérengère
name: Chavanis, Pierre-Henri
Publisher: name: arXiv
Year: 2005
Subjects: subject: Fluid Dynamics (physics.flu-dyn)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: We develop new variational principles to study stability and equilibrium of axisymmetric flows. We show that there is an infinite number of steady state solutions. We show that these steady states maximize a (non-universal) $H$-function. We derive relaxation equations which can be used as numerical algorithm to construct stable stationary solutions of axisymmetric flows. In a second part, we develop a thermodynamical approach to the equilibrium states at some fixed coarse-grained scale. We show that the resulting distribution can be divided in a universal part coming from the conservation of robust invariants and one non-universal determined by the initial conditions through the fragile invariants (for freely evolving systems) or by a prior distribution encoding non-ideal effects such as viscosity, small-scale forcing and dissipation (for forced systems). Finally, we derive a parameterization of inviscid mixing to describe the dynamics of the system at the coarse-grained scale.
Strange molecular partners of the $Z_c(3900)$ and $Z_c(4020)$
Creators: name: Yang, Zhi
name: Cao, Xu
name: Guo, Feng-Kun
name: Nieves, Juan
name: Valderrama, Manuel Pavon
Publisher: name: arXiv
Year: 2020
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Experiment (hep-ex)
subject: High Energy Physics - Lattice (hep-lat)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: Quantum Chromodynamics presents a series of exact and approximate symmetries which can be exploited to predict new hadrons from previously known ones. The $Z_c(3900)$ and $Z_c(4020)$ resonances, which have been theorized to be isovector $D^* \bar{D}$ and $D^* \bar{D}^*$ molecules [$I^G(J^{PC}) = 1^-(1^{+-})$], are no exception. Here we argue that from SU(3)-flavor symmetry, we should expect the existence of strange partners of the $Z_c$'s with hadronic molecular configurations $D^* \bar{D}_s$-$D \bar{D}_s^*$ and $D^* \bar{D}^{*}_s$ (or, equivalently, quark content $c\bar{c} s \bar{q}$, with $q = u, d$). The quantum numbers of these $Z_{cs}$ and $Z_{cs}^*$ resonances would be $I(J^P)$ = $\frac{1}{2}(1^+)$. The predicted masses of these partners depend on the details of the theoretical scheme used, but they should be around the $D^* \bar{D}_s$-$D \bar{D}_s^*$ and $D^* \bar{D}^{*}_s$ thresholds, respectively. Moreover, any of these states could be either a virtual pole or a resonance. We show that, together with a possible triangle singularity contribution, such a picture nicely agrees with the very recent BESIII data of the $e^+e^-\to K^+(D_s^-D^{*0}+D_s^{*-}D^0)$.
description: 8 pages, 5 figures; note added commenting on the Zcs structures reported recently by LHCb
IMPACTS OF POLICY REFORM ON SUSTAINABILITY OF HILL FARMING IN UK BY MEANS OF BIO-ECONOMIC MODELLING
Creators: name: Acs, Szvetlana
name: Hanley, Nick
name: Dallimer, Martin
name: Robertson, Philip
name: Gaston, Kevin J.
name: Armsworth, Paul R.
name: Acs, Szvetlana
name: Hanley, Nick
name: Dallimer, Martin
name: Robertson, Philip
name: Gaston, Kevin J.
name: Armsworth, Paul R.
Publisher: name: Unknown
Year: 2008
Subjects: subject: Agricultural and Food Policy
subject: Crop Production/Industries
subject: Farm Management
subject: Land Economics/Use
subject: CAP reform
subject: Single Farm Payment
subject: hill farming
subject: linear programming model

description: Hill farming in UK is experiencing very difficult economic circumstances and many farmers rely on subsidies provided by the government for a large fraction of their income. The Peak District National Park is used as a case study to examine how farmers might respond to current policy changes � in particular, the move from area- and headage-based payments to the Single Farm Payment, and how optimal business plans should respond to these changes. The objective of this paper is thus to develop production models that predict how farmers will respond to changing policy framework conditions. For this purpose socio-economic surveys were carried out on 44 sample farms, in order to investigate how the land is managed on hill farms including ongoing policies and future farm management planning. Based on these surveys a series of representative farm linear programming models was developed, which represent typical farm types in the uplands in the Peak District. In this study the focus is on typical sheep and beef farm type, the most common in this region. This model is used to calculate the effect of different policies, carried out under CAP reform, on incomes, land use and the intensity of production. We also consider the impacts of a complete removal of subsidy.
Growth Rate and Configurational Entropy in Tsallis Holographic Dark Energy
Creators: name: Bhattacharjee, Snehasish
Publisher: name: arXiv
Year: 2020
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: In this work, we analyzed the effect of different prescriptions of the IR cutoffs, namely the Hubble horizon cutoff, particle horizon cutoff, Granda and Oliveros horizon cut off, and the Ricci horizon cutoff on the growth rate of clustering for the Tsallis holographic dark energy (THDE) model in an FRW universe devoid of any interactions between the dark Universe. Furthermore, we used the concept of configurational entropy to derive constraints (qualitatively) on the model parameters for the THDE model in each IR cutoff prescription from the fact that the rate of change of configurational entropy hits a minimum at a particular scale factor $a_{DE}$ which indicate precisely the epoch of dark energy domination predicted by the relevant cosmological model as a function of the model parameter(s). By using the current observational constraints on the redshift of transition from a decelerated to an accelerated Universe, we derived constraints on the model parameters appearing in each IR cutoff definition and on the non-additivity parameter $δ$ characterizing the THDE model and report the existence of simple linear dependency between $δ$ and $a_{DE}$ in each IR cutoff setup.
ESTIMATING THE EFFECT OF WATER CHARGE INTRODUCTION AT SMALL-SCALE IRRIGATION SCHEMES IN NORTH WEST PROVINCE, SOUTH AFRICA
Creators: name: Speelman, Stijn
name: Buysse, Jeroen
name: Frija, Aymen
name: D'Haese, Marijke F.C.
name: D'Haese, Luc
name: Speelman, Stijn
name: Buysse, Jeroen
name: Frija, Aymen
name: D'Haese, Marijke F.C.
name: D'Haese, Luc
Publisher: name: Unknown
Year: 2008
Subjects: Production Economics
Resource /Energy Economics and Policy

description: In South Africa water law has recently changed, adopting the principle of water as an economic good, thus levying charges on its use. For small-scale irrigators this is an important change, because currently their water use is entirely subsidized. In the coming years, subsidies will gradually decrease and an essential expected benefit of this policy change is that water use efficiency will rise, leading to reduced consumption and possible reallocation of the water saved. The exact impact of the water pricing policy on the irrigation water use or on the farmers' production system is however unclear. This study introduces a new methodology, based on data envelopment analysis, that allows estimating the effects on the agricultural production process and water demand of introducing or raising a water price. It is revealed that a large majority of the farmers does not adjust water use. Production costs however were shown to increase significantly.
Nickelate superconductors: an ongoing dialog between theory and experiments
Creators: name: Botana, A. S.
name: Bernardini, F.
name: Cano, A.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: Materials Science (cond-mat.mtrl-sci)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: After decades of fundamental research, unconventional superconductivity has recently been demonstrated in rare-earth infinite-layer nickelates. The current view depicts these systems as a new category of superconducting materials, as they appear to be correlated metals with distinct multiband features in their phase diagram. Here, we provide an overview of the state of the art in this rapidly evolving topic.
description: 9 pages, 6 figures. Review article for the JETP special issue celebrating I. E. Dzyaloshinskii's 90th birthday. v2 updated references & minor typos corrected
Gauge invariant fluid lagrangian and its application to cosmology
Creators: name: Sulaiman, A.
name: Djun, T. P.
name: Handoko, L. T.
Publisher: name: arXiv
Year: 2005
Subjects: subject: Fluid Dynamics (physics.flu-dyn)
subject: FOS: Physical sciences

description: A lagrangian for relativistic fluid systems with matters inside is developed using gauge principle. In the model, the gauge boson represents the fluid field in a form $A_μ\equiv ε_μϕ$, where $ε_μ$ contains the fluid kinematics and $ϕ$ is an auxiliary field representing the fluid distribution. This leads to a new relativistic equation of motion for fluid, but which further coincides to the classical Euler equation at non-relativistic limit. The lagrangian is applied to model homogeneous universe as a bulk pure fluid system. Taking the simplest case of fluid with radial velocity and uniform distribution, the free energy density is calculated and its behaviour around Hubble distance is discussed.
description: 7 pages, revised version for journal publication and adding an application to cosmology
Surfing on minima of isostatic landscapes: avalanches and unjamming transition
Creators: name: Franz, Silvio
name: Sclocchi, Antonio
name: Urbani, Pierfrancesco
Publisher: name: arXiv
Year: 2020
Subjects: subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: Recently, we showed that optimization problems, both in infinite as well as in finite dimensions, for continuous variables and soft excluded volume constraints, can display entire isostatic phases where local minima of the cost function are marginally stable configurations endowed with non-linear excitations [1,2]. In this work we describe an athermal adiabatic algorithm to explore with continuity the corresponding rough high-dimensional landscape. We concentrate on a prototype problem of this kind, the spherical perceptron optimization problem with linear cost function (hinge loss). This algorithm allows to "surf" between isostatic marginally stable configurations and to investigate some properties of such landscape. In particular we focus on the statistics of avalanches occurring when local minima are destabilized. We show that when perturbing such minima, the system undergoes plastic rearrangements whose size is power law distributed and we characterize the corresponding critical exponent. Finally we investigate the critical properties of the unjamming transition, showing that the linear interaction potential gives rise to logarithmic behavior in the scaling of energy and pressure as a function of the distance from the unjamming point. For some quantities, the logarithmic corrections can be gauged out. This is the case of the number of soft constraints that are violated as a function of the distance from jamming which follows a non-trivial power law behavior.
description: 22 pages, 13 figures
LAND MARKETS IN AGENT BASED MODELS OF STRUCTURAL CHANGE
Creators: name: Kellermann, Konrad
name: Sahrbacher, Christoph
name: Balmann, Alfons
name: Kellermann, Konrad
name: Sahrbacher, Christoph
name: Balmann, Alfons
Publisher: name: Unknown
Year: 2008
Subjects: Land Economics/Use
Research Methods/ Statistical Methods

description: Land markets play a crucial role in agricultural structural change. The dynamics on land markets mainly depend on the interactions between individual farms. Agent-based modelling (ABM) provides one way to take the specific characteristics of land transactions into account, as it allows to model interactions between different agents as well as spatial relationships in a straightforward manner. However, reviewing the literature one can find only a few attempts of endogenized land markets in ABM. Furthermore, it seems that the allocation mechanisms of these endogenized land markets are chosen rather arbitrarily and not much attention is given to an intensive discussion of the impact of the respective allocation mechanisms to simulation results. To close this gap the aim of this paper is threefold: First we want to give a brief review of existing ABM with endogenized land allocation mechanisms and we identify a theoretical framework which serves as a guidance to develop a suitable and extendable land market (sub-) model. Second, we derive a number of relevant design considerations necessary to endogenize land transactions in an agent based modelling framework. Based on this we propose three different land market implementations which are based on auction mechanisms. In order to be able to evaluate the different implementations not only in relative but also in absolute terms we furthermore propose an approach to create a global optimal allocation in terms of the resulting economic land rent. For this we use a mathematical programming approach to solve the underlying allocation problem and the concept of average shadow prices to price the allocated plots. In the third part we show the practical implications of different allocation mechanisms. This is done using the spatial and dynamic agent-based simulation model AgriPoliS as experimental laboratory. In that way we can analyse the properties of the respective allocation mechanisms in a realistic framework which is based on a detailed empirical calibration.
description: Replaced with revised version of paper 02/22/08.
Size and Properties of the NLR in the Seyfert-2 Galaxy NGC 1386
Creators: name: Bennert, Nicola
name: Jungwiert, Bruno
name: Komossa, Stefanie
name: Haas, Martin
name: Chini, Rolf
Publisher: name: arXiv
Year: 2005
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We study the narrow-line region (NLR) of the Seyfert-2 galaxy NGC 1386 by means of long-slit spectroscopy obtained with FORS1 at the VLT. We use the galaxy itself for subtracting the stellar template, applying reddening corrections to fit the stellar template to the spectra of the NLR. The continuum gets steadily redder towards the nucleus. The spatial distribution of the reddening derived from the Balmer decrement differs from the continuum reddening, indicating dust within the NLR with a varying column density along the line of sight. Using spatially resolved spectral diagnostics, we find a transition between central line ratios falling into the AGN regime and outer ones in the HII-region regime, occuring at a radius of ~6 arcsec (310 pc) in all three diagnostic diagrams. Applying CLOUDY photoionisation models, we show that the observed distinction between HII-like and AGN-like ratios in NGC 1386 represents a true difference in ionisation source and cannot be explained by variations of physical parameters such as ionisation parameter, electron density or metallicity. We interpret it as a real border between the NLR, i.e. the central AGN-photoionised region and surrounding HII regions. We derive surface brightness, electron density, and ionisation parameter as a function of distance from the nucleus. Both the electron density and the ionisation parameter decrease with radius. We discuss the consequences of these observations for the interpretation of the empirical NLR size-luminosity relation. In the outer part of the NLR, we find evidence for shocks, resulting in a secondary peak of the electron-density and ionisation-parameter distribution north of the nucleus. We compare the NLR velocity curve with the stellar one and discuss the differences.
description: 14 pages, 20 figures, accepted for publication in A&A
Third order Møller-Plesset theory made more useful? The role of density functional theory orbitals
Creators: name: Rettig, Adam
name: Hait, Diptarka
name: Bertels, Luke W.
name: Head-Gordon, Martin
Publisher: name: arXiv
Year: 2020
Subjects: subject: Chemical Physics (physics.chem-ph)
subject: Other Condensed Matter (cond-mat.other)
subject: FOS: Physical sciences

description: The practical utility of Møller-Plesset (MP) perturbation theory is severely constrained by the use of Hartree-Fock (HF) orbitals. It has recently been shown that use of regularized orbital-optimized MP2 orbitals and scaling of MP3 energy could lead to a significant reduction in MP3 error (J. Phys. Chem. Lett. 10, 4170, 2019). In this work we examine whether density functional theory (DFT) optimized orbitals can be similarly employed to improve the performance of MP theory at both the MP2 and MP3 levels. We find that use of DFT orbitals leads to significantly improved performance for prediction of thermochemistry, barrier heights, non-covalent interactions, and dipole moments relative to standard HF based MP theory. Indeed MP3 (with or without scaling) with DFT orbitals is found to surpass the accuracy of coupled cluster singles and doubles (CCSD) for several datasets. We also found that the results are not particularly functional sensitive in most cases, (although range-separated hybrid functionals with low delocalization error perform the best). MP3 based on DFT orbitals thus appears to be an efficient, non-iterative $O(N^6)$ scaling wave function approach for single-reference electronic structure computations. Scaled MP2 with DFT orbitals is also found to be quite accurate in many cases, although modern double hybrid functionals are likely to be considerably more accurate.
Message Transfer in a Communication Network
Creators: name: Mukherjee, Satyam
name: Gupte, Neelima
Publisher: name: arXiv
Year: 2008
Subjects: subject: Physics and Society (physics.soc-ph)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Adaptation and Self-Organizing Systems (nlin.AO)
subject: Data Analysis, Statistics and Probability (physics.data-an)
subject: FOS: Physical sciences

description: We study message transfer in a $2-d$ communication network of regular nodes and randomly distributed hubs. We study both single message transfer and multiple message transfer on the lattice. The average travel time for single messages travelling between source and target pairs of fixed separations shows $q-$exponential behaviour as a function of hub density with a characteristic power-law tail, indicating a rapid drop in the average travel time as a function of hub density. This power-law tail arises as a consequence of the log-normal distribution of travel times seen at high hub densities. When many messages travel on the lattice, a congestion-decongestion transition can be seen. The waiting times of messages in the congested phase show a Gaussian distribution, whereas the decongested phase shows a log-normal distribution. Thus, the congested or decongested behaviour is encrypted in the behaviour of the waiting time distributions.
description: 7 Pages, 6 figure, to appear in the Proceeding of the conference Perspectives in Nonlinear Dynamics 2007, a special issue of the Journal Pramana
Checking vocabulary from published texts
Creators: name: Parker, Verdena
name: Spence, Justin
Publisher: name: California Language Archive, University of California, Berkeley
Year: 2020
Subjects: subject: hup

description: Audio files VP-160717-03a/c: Checking vocabulary with uncertain analyses from texts in Goddard 1904 ("Hupa Texts," University of California Publications in American Archaeology and Ethnology 1(2): 89-368)
Least favorability of the uniform distribution for tests of the concavity of a distribution function
Creators: name: Beare, Brendan K.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Statistics Theory (math.ST)
subject: FOS: Mathematics

description: A test of the concavity of a distribution function with support contained in the unit interval may be based on a statistic constructed from the $L^p$-norm of the difference between an empirical distribution function and its least concave majorant. It is shown here that the uniform distribution is least favorable for such a test, in the sense that the limiting distribution of the statistic obtained under uniformity stochastically dominates the limiting distribution obtained under any other concave distribution function.
DFT study of pressure induced phase transitions in LiYF4
Creators: name: Minisini, Benoit
name: Hadj, Labidi El
name: Fomena, Mireille Lontsi
name: Van Garderen, Noemie
name: Tsobnang, Francois
Publisher: name: arXiv
Year: 2005
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: An investigation of the pressure induced phase transition from the scheelite phase (I41/a, Z=4) to the fergusonite-like phase (I2/a, Z=4)/LaTaO(P21/c, Z=4) of LiYF4 is presented. Employing density functional theory (DFT) within the generalized gradient approximation, the internal degrees of freedom were relaxed for a pressure range of 0 GPa to 20 Gpa. The influence of pressure on the lattice vibration spectrum of the scheelite phase (I41/a, Z=4) was evaluated using the direct approach, i.e. using force constants calculated from atomic displacements. The transition volume is in good agreement with experiment, while the transition pressure is overestimated of 6 GPa. At 20 GPa, a P21/c structure with apentacoordinated lithium cation is found to be the most stable phase. This structure is compatible with a transition driven by a Bg zone-center soft optic mode linked to a soft-acoustic mode along the [11-1] direction as observed for the proper ferroelastic transition of BiVO4.
Linear and Bayesian Planet Detection Algorithms for the Terrestrial Planet Finder
Creators: name: Kasdin, N. Jeremy
name: Braems, Isabelle
Publisher: name: arXiv
Year: 2006
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: Current plans call for the first Terrestrial Planet Finder mission, TPF-C, to be a monolithic space telescope with a coronagraph for achieving high contrast. The coronagraph removes the diffracted starlight allowing the nearby planet to be detected. In this paper, we present a model of the planet measurement and noise statistics. We utilize this model to develop two planet detection algorithms, one based on matched filtering of the PSF and one using Bayesian techniques. These models are used to formulate integration time estimates for a planet detection with desired small probabilities of false alarms and missed detections.
Giving Semantics to Program-Counter Labels via Secure Effects
Creators: name: Hirsch, Andrew K.
name: Cecchetti, Ethan
Publisher: name: arXiv
Year: 2020
Subjects: subject: Programming Languages (cs.PL)
subject: Cryptography and Security (cs.CR)
subject: FOS: Computer and information sciences
subject: D.4.6; F.3.2

description: Type systems designed for information-flow control commonly use a program-counter label to track the sensitivity of the context and rule out data leakage arising from effectful computation in a sensitive context. Currently, type-system designers reason about this label informally except in security proofs, where they use ad-hoc techniques. We develop a framework based on monadic semantics for effects to give semantics to program-counter labels. This framework leads to three results about program-counter labels. First, we develop a new proof technique for noninterference, the core security theorem for information-flow control in effectful languages. Second, we unify notions of security for different types of effects, including state, exceptions, and nontermination. Finally, we formalize the folklore that program-counter labels are a lower bound on effects. We show that, while not universally true, this folklore has a good semantic foundation.
The value of B_K from the experimental data on CP-violation in K-mesons and up-to-date values of CKM matrix parameters
Creators: name: Andriyash, E. A.
name: Ovanesyan, G. G.
name: Vysotsky, M. I.
Publisher: name: arXiv
Year: 2005
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: The difference between induced by box diagram quantity \tilde εand experimentally measured value of εis determined and used to obtain the value of \tilde εwith high precision. Present day knowledge of CKM matrix elements (including B-factory data), allows us to obtain from the Standard Model expression for \tilde εthe value of parameter B_K: B_K = 0.89 \pm0.16. It turns out to be very close to the result of vacuum insertion, B_K = 1.
description: 12 pages, 1 figure
ORGANISATION UND BEWERTUNG DES QUALITY MANAGEMENTS BEI DER HERSTELLUNG GENTECHNIK FREIER PRODUKTE AM BEISPIEL DER RAPS- UND SOJAVERARBEITUNG (German)
Creators: name: Hirzinger, Tobias
name: Menrad, Klaus
name: Bez, Jurgen
name: Hirzinger, Tobias
name: Menrad, Klaus
name: Bez, Jurgen
Publisher: name: Unknown
Year: 2007
Subjects: subject: Production Economics
subject: Gentechnik
subject: Lebensmittel
subject: Koexistenz
subject: GVO-Vermeidungskosten

description: In Deutschland erfolgt die Herstellung von Sojaöl ausschließlich unter Verwendung importierter Sojabohnen und es wird von Seiten der Ölmühlen ein erweitertes Qualitätsmanagement durchgeführt, um die Anforderungen der EU-Gentechnikgesetzgebung und den Schwellenwert von weniger als 0,9% GVO1-Anteil im Produkt einzuhalten. Sollte in der EU gv-Raps in größeren Mengen angebaut oder gehandelt werden, so müsste auch bei der Rapsölproduktion wie bereits in der Sojaölproduktion ein erweitertes Qualitätsmanagement zur GVO-Vermeidung durchgeführt werden. Befinden sich GVO in der Supply Chain sind die zusätzlichen Kosten der GVO-Vermeidung in erster Linie Kosten für GVO-Analytik und höhere Kosten für garantiert gentechnik freie Rohstoffe. Bei Sojaöl kann die GVOVermeidung den Produktpreis um bis 25% verteuern, bezogen auf gv-Sojaöl, und bei Rapsöl können die GVO-Vermeidungskosten bis zu 12% betragen, bezogen auf den aktuellen Produktpreis von konventionellem Rapsöl.
Isospin breaking and the chiral condensate
Creators: name: Creutz, Michael
Publisher: name: arXiv
Year: 2005
Subjects: subject: High Energy Physics - Lattice (hep-lat)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: With two degenerate quarks, the chiral condensate exhibits a jump as the quark masses pass through zero. I discuss how this single transition splits into two Ising like transitions when the quarks are made non-degenerate. The order parameter is the expectation of the neutral pion field. The transitions represent long distance coherent phenomena occuring without the Dirac operator having vanishingly small eigenvalues.
description: 6 pages, 3 figures; contribution to the XXIIIrd International Symposium on Lattice Field Theory, 25-30 July 2005, Trinity College, Dublin, Ireland
The ${\cal N}=4$ Higher Spin Algebra for Generic $μ$ Parameter
Creators: name: Ahn, Changhyun
name: Kim, Man Hea
Publisher: name: arXiv
Year: 2020
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: The ${\cal N}=4$ higher spin generators for general superspin $s$ in terms of oscillators in the matrix generalization of $AdS_3$ Vasiliev higher spin theory at nonzero $μ$ (which is equivalent to the 't Hooft-like coupling constant $λ$) were found previously. In this paper, by computing the (anti)commutators between these ${\cal N}=4$ higher spin generators for low spins $s_1$ and $s_2$ ($s_1+s_2 \leq 11$) explicitly, we determine the complete ${\cal N}=4$ higher spin algebra for generic $μ$. The three kinds of structure constants contain the linear combination of two different generalized hypergeometric functions. These structure constants remain the same under the transformation $μ\leftrightarrow (1-μ)$ up to signs. We have checked that the above ${\cal N}=4$ higher spin algebra contains the ${\cal N}=2$ higher spin algebra, as a subalgebra, found by Fradkin and Linetsky some time ago.
description: 67 pages. The last statement of the subsection 2.1, the footnotes 4 and 6 and the bounds of the summation is are added. The equations (2.5),(2.6) and (4.15) are improved. The original section 5 is moved to Appendix F with the addition of the first paragraph. To appear in JHEP
A Recommender System based on the Immune Network
Creators: name: Cazyer, Steve
name: Aickelin, Uwe
Publisher: name: arXiv
Year: 2008
Subjects: subject: Neural and Evolutionary Computing (cs.NE)
subject: Artificial Intelligence (cs.AI)
subject: FOS: Computer and information sciences

description: The immune system is a complex biological system with a highly distributed, adaptive and self-organising nature. This paper presents an artificial immune system (AIS) that exploits some of these characteristics and is applied to the task of film recommendation by collaborative filtering (CF). Natural evolution and in particular the immune system have not been designed for classical optimisation. However, for this problem, we are not interested in finding a single optimum. Rather we intend to identify a sub-set of good matches on which recommendations can be based. It is our hypothesis that an AIS built on two central aspects of the biological immune system will be an ideal candidate to achieve this: Antigen - antibody interaction for matching and antibody - antibody interaction for diversity. Computational results are presented in support of this conjecture and compared to those found by other CF techniques.