Interaction-induced decay of a heteronuclear two-atom system

PubMed Central

Xu, Peng; Yang, Jiaheng; Liu, Min; He, Xiaodong; Zeng, Yong; Wang, Kunpeng; Wang, Jin; Papoular, D. J.; Shlyapnikov, G. V.; Zhan, Mingsheng

2015-01-01

Two-atom systems in small traps are of fundamental interest for understanding the role of interactions in degenerate cold gases and for the creation of quantum gates in quantum information processing with single-atom traps. One of the key quantities is the inelastic relaxation (decay) time when one of the atoms or both are in a higher hyperfine state. Here we measure this quantity in a heteronuclear system of 87Rb and 85Rb in a micro optical trap and demonstrate experimentally and theoretically the presence of both fast and slow relaxation processes, depending on the choice of the initial hyperfine states. This experimental method allows us to single out a particular relaxation process thus provides an extremely clean platform for collisional physics studies. Our results have also implications for engineering of quantum states via controlled collisions and creation of two-qubit quantum gates. PMID:26199051

Beyond METs: types of physical activity and depression among older adults

PubMed Central

Joshi, Spruha; Mooney, Stephen J.; Kennedy, Gary J.; Benjamin, Ebele O.; Ompad, Danielle; Rundle, Andrew G.; Beard, John R.; Cerdá, Magdalena

2016-01-01

Background/Objectives: physical activity may be beneficial in reducing depression incidence among the elderly. A key unanswered question is whether certain types of physical activity are particularly associated with decreased depression incidence. We examined the relationship between quantity and type of physical activity and subsequent depression using longitudinal data from elderly adults in New York City (NYC). Methods: we followed 3,497 adults aged 65–75 living in NYC for three years. Total physical activity was measured using the Physical Activity Scale for the Elderly (PASE) and type of physical activity was measured using a latent class analysis of PASE item responses. We used generalised estimating equations to measure the relationship between quantity and latent class of physical activity at waves 1–2 and depression at waves 2–3, controlling for wave-1 depression. Results: individuals in the second highest quartile (50–75%) (odds ratio (OR) = 0.45; 95% confidence interval (CI) = 0.23, 0.88) and highest quartile of activity (OR = 0.31; 95% CI = 0.16, 0.63) had lower odds of depression. Among all subjects, athletic types (OR = 0.25; 95% CI = 0.12, 0.51) and walker types (OR = 0.58; 95% CI = 0.34, 0.99) had lower odds of depression. Among non-disabled participants, walkers (OR = 0.36; 95% CI = 0.18, 0.73), athletic types (OR = 0.14; 95% CI = 0.06, 0.32), domestic/gardening types (OR = 0.29; 95% CI = 0.12, 0.73) and domestic/gardening athletic types (OR = 0.13; 95% CI = 0.02, 0.75) had lower odds of depression. Conclusion: respondents who practised the highest levels of physical activity and who performed athletic activities were at lower risk for depression. Interventions aimed at promoting athletic physical activity among older adults may generate benefits for mental health. PMID:26764399

Beyond METs: types of physical activity and depression among older adults.

PubMed

Joshi, Spruha; Mooney, Stephen J; Kennedy, Gary J; Benjamin, Ebele O; Ompad, Danielle; Rundle, Andrew G; Beard, John R; Cerdá, Magdalena

2016-01-01

physical activity may be beneficial in reducing depression incidence among the elderly. A key unanswered question is whether certain types of physical activity are particularly associated with decreased depression incidence. We examined the relationship between quantity and type of physical activity and subsequent depression using longitudinal data from elderly adults in New York City (NYC). we followed 3,497 adults aged 65-75 living in NYC for three years. Total physical activity was measured using the Physical Activity Scale for the Elderly (PASE) and type of physical activity was measured using a latent class analysis of PASE item responses. We used generalised estimating equations to measure the relationship between quantity and latent class of physical activity at waves 1-2 and depression at waves 2-3, controlling for wave-1 depression. individuals in the second highest quartile (50-75%) (odds ratio (OR) = 0.45; 95% confidence interval (CI) = 0.23, 0.88) and highest quartile of activity (OR = 0.31; 95% CI = 0.16, 0.63) had lower odds of depression. Among all subjects, athletic types (OR = 0.25; 95% CI = 0.12, 0.51) and walker types (OR = 0.58; 95% CI = 0.34, 0.99) had lower odds of depression. Among non-disabled participants, walkers (OR = 0.36; 95% CI = 0.18, 0.73), athletic types (OR = 0.14; 95% CI = 0.06, 0.32), domestic/gardening types (OR = 0.29; 95% CI = 0.12, 0.73) and domestic/gardening athletic types (OR = 0.13; 95% CI = 0.02, 0.75) had lower odds of depression. respondents who practised the highest levels of physical activity and who performed athletic activities were at lower risk for depression. Interventions aimed at promoting athletic physical activity among older adults may generate benefits for mental health. © The Author 2016. Published by Oxford University Press on behalf of the British Geriatrics Society. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Recognizing Prefixes in Scientific Quantities

ERIC Educational Resources Information Center

Sokolowski, Andrzej

2015-01-01

Although recognizing prefixes in physical quantities is inherent for practitioners, it might not be inherent for students, who do not use prefixes in their everyday life experiences. This deficiency surfaces in AP Physics exams. For example, readers of an AP Physics exam reported "a common mistake of incorrectly converting nanometers to…

Exploring Flavor Physics with Lattice QCD

NASA Astrophysics Data System (ADS)

Du, Daping; Fermilab/MILC Collaborations Collaboration

2016-03-01

The Standard Model has been a very good description of the subatomic particle physics. In the search for physics beyond the Standard Model in the context of flavor physics, it is important to sharpen our probes using some gold-plated processes (such as B rare decays), which requires the knowledge of the input parameters, such as the Cabibbo-Kobayashi-Maskawa (CKM) matrix elements and other nonperturbative quantities, with sufficient precision. Lattice QCD is so far the only first-principle method which could compute these quantities with competitive and systematically improvable precision using the state of the art simulation techniques. I will discuss the recent progress of lattice QCD calculations on some of these nonpurturbative quantities and their applications in flavor physics. I will also discuss the implications and future perspectives of these calculations in flavor physics.

On the Lagrangian description of dissipative systems

NASA Astrophysics Data System (ADS)

Martínez-Pérez, N. E.; Ramírez, C.

2018-03-01

We consider the Lagrangian formulation with duplicated variables of dissipative mechanical systems. The application of Noether theorem leads to physical observable quantities which are not conserved, like energy and angular momentum, and conserved quantities, like the Hamiltonian, that generate symmetry transformations and do not correspond to observables. We show that there are simple relations among the equations satisfied by these two types of quantities. In the case of the damped harmonic oscillator, from the quantities obtained by the Noether theorem follows the algebra of Feshbach and Tikochinsky. Furthermore, if we consider the whole dynamics, the degrees of freedom separate into a physical and an unphysical sector. We analyze several cases, with linear and nonlinear dissipative forces; the physical consistency of the solutions is ensured, observing that the unphysical sector has always the trivial solution.

Social Change and Equilibration of Cognitive Structures: The Role of Schooling and Urbanisation.

ERIC Educational Resources Information Center

Lalo, A.

1989-01-01

Investigated the role of schooling and urbanization on the acquisition of conservation of physical quantities in 384 Senagalese children of 7, 9, 11, and 13 years. Results revealed functional divergences in the acquisition of physical quantities. (RJC)

Cross-format physical similarity effects and their implications for the numerical cognition architecture

PubMed Central

Cohen, Dale J.; Warren, Erin; Blanc-Goldhammer, Daryn

2013-01-01

The sound |faiv| is visually depicted as a written number word “five” and as an Arabic digit “5.” Here, we present four experiments – two quantity same/different experiments and two magnitude comparison experiments – that assess whether auditory number words (|faiv|), written number words (“five”), and Arabic digits (“5”) directly activate one another and/or their associated quantity. The quantity same/different experiments reveal that the auditory number words, written number words, and Arabic digits directly activate one another without activating their associated quantity. That is, there are cross-format physical similarity effects but no numerical distance effects. The cross-format magnitude comparison experiments reveal significant effects of both physical similarity and numerical distance. We discuss these results in relation to the architecture of numerical cognition. PMID:23624377

Shannon information entropy in heavy-ion collisions

NASA Astrophysics Data System (ADS)

Ma, Chun-Wang; Ma, Yu-Gang

2018-03-01

The general idea of information entropy provided by C.E. Shannon "hangs over everything we do" and can be applied to a great variety of problems once the connection between a distribution and the quantities of interest is found. The Shannon information entropy essentially quantify the information of a quantity with its specific distribution, for which the information entropy based methods have been deeply developed in many scientific areas including physics. The dynamical properties of heavy-ion collisions (HICs) process make it difficult and complex to study the nuclear matter and its evolution, for which Shannon information entropy theory can provide new methods and observables to understand the physical phenomena both theoretically and experimentally. To better understand the processes of HICs, the main characteristics of typical models, including the quantum molecular dynamics models, thermodynamics models, and statistical models, etc., are briefly introduced. The typical applications of Shannon information theory in HICs are collected, which cover the chaotic behavior in branching process of hadron collisions, the liquid-gas phase transition in HICs, and the isobaric difference scaling phenomenon for intermediate mass fragments produced in HICs of neutron-rich systems. Even though the present applications in heavy-ion collision physics are still relatively simple, it would shed light on key questions we are seeking for. It is suggested to further develop the information entropy methods in nuclear reactions models, as well as to develop new analysis methods to study the properties of nuclear matters in HICs, especially the evolution of dynamics system.

Towards ab initio Calculations with the Dynamical Vertex Approximation

NASA Astrophysics Data System (ADS)

Galler, Anna; Kaufmann, Josef; Gunacker, Patrik; Pickem, Matthias; Thunström, Patrik; Tomczak, Jan M.; Held, Karsten

2018-04-01

While key effects of the many-body problem — such as Kondo and Mott physics — can be understood in terms of on-site correlations, non-local fluctuations of charge, spin, and pairing amplitudes are at the heart of the most fascinating and unresolved phenomena in condensed matter physics. Here, we review recent progress in diagrammatic extensions to dynamical mean-field theory for ab initio materials calculations. We first recapitulate the quantum field theoretical background behind the two-particle vertex. Next we discuss latest algorithmic advances in quantum Monte Carlo simulations for calculating such two-particle quantities using worm sampling and vertex asymptotics, before giving an introduction to the ab initio dynamical vertex approximation (AbinitioDΓA). Finally, we highlight the potential of AbinitioDΓA by detailing results for the prototypical correlated metal SrVO3.

Conservation laws and conserved quantities for (1+1)D linearized Boussinesq equations

NASA Astrophysics Data System (ADS)

Carvalho, Cindy; Harley, Charis

2017-05-01

Conservation laws and physical conserved quantities for the (1+1)D linearized Boussinesq equations at a constant water depth are presented. These equations describe incompressible, inviscid, irrotational fluid flow in the form of a non steady solitary wave. A systematic multiplier approach is used to obtain the conservation laws of the system of third order partial differential equations (PDEs) in dimensional form. Physical conserved quantities are derived by integrating the conservation laws in the direction of wave propagation and imposing decaying boundary conditions in the horizontal direction. One of these is a newly discovered conserved quantity which relates to an energy flux density.

Techniques for determining physical zones of influence

DOEpatents

Hamann, Hendrik F; Lopez-Marrero, Vanessa

2013-11-26

Techniques for analyzing flow of a quantity in a given domain are provided. In one aspect, a method for modeling regions in a domain affected by a flow of a quantity is provided which includes the following steps. A physical representation of the domain is provided. A grid that contains a plurality of grid-points in the domain is created. Sources are identified in the domain. Given a vector field that defines a direction of flow of the quantity within the domain, a boundary value problem is defined for each of one or more of the sources identified in the domain. Each of the boundary value problems is solved numerically to obtain a solution for the boundary value problems at each of the grid-points. The boundary problem solutions are post-processed to model the regions affected by the flow of the quantity on the physical representation of the domain.

The accuracy of less: Natural bounds explain why quantity decreases are estimated more accurately than quantity increases.

PubMed

Chandon, Pierre; Ordabayeva, Nailya

2017-02-01

Five studies show that people, including experts such as professional chefs, estimate quantity decreases more accurately than quantity increases. We argue that this asymmetry occurs because physical quantities cannot be negative. Consequently, there is a natural lower bound (zero) when estimating decreasing quantities but no upper bound when estimating increasing quantities, which can theoretically grow to infinity. As a result, the "accuracy of less" disappears (a) when a numerical or a natural upper bound is present when estimating quantity increases, or (b) when people are asked to estimate the (unbounded) ratio of change from 1 size to another for both increasing and decreasing quantities. Ruling out explanations related to loss aversion, symbolic number mapping, and the visual arrangement of the stimuli, we show that the "accuracy of less" influences choice and demonstrate its robustness in a meta-analysis that includes previously published results. Finally, we discuss how the "accuracy of less" may explain asymmetric reactions to the supersizing and downsizing of food portions, some instances of the endowment effect, and asymmetries in the perception of increases and decreases in physical and psychological distance. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Star formation trends in high-redshift galaxy surveys: the elephant or the tail?

NASA Astrophysics Data System (ADS)

Stringer, Martin; Cole, Shaun; Frenk, Carlos S.; Stark, Daniel P.

2011-07-01

Star formation rate and accumulated stellar mass are two fundamental physical quantities that describe the evolutionary state of a forming galaxy. Two recent attempts to determine the relationship between these quantities, by interpreting a sample of star-forming galaxies at redshift of z˜ 4, have led to opposite conclusions. Using a model galaxy population, we investigate possible causes for this discrepancy and conclude that minor errors in the conversion from observables to physical quantities can lead to a major misrepresentation when applied without awareness of sample selection. We also investigate, in a general way, the physical origin of the correlation between star formation rate and stellar mass within the hierarchical galaxy formation theory.

Testing galaxy quenching theories with scatter in the stellar-to-halo mass relation

NASA Astrophysics Data System (ADS)

Tinker, Jeremy L.

2017-05-01

We use the scatter in the stellar-to-halo mass relation to constrain galaxy evolution models. If the efficiency of converting accreted baryons into stars varies with time, haloes of the same present-day mass but different formation histories will have different z = 0 galaxy stellar mass. This is one of the sources of scatter in stellar mass at fixed halo mass, σlog M*. For massive haloes that undergo rapid quenching of star formation at z ˜ 2, different mechanisms that trigger this quenching yield different values of σlog M*. We use this framework to test various models in which quenching begins after a galaxy crosses a threshold in one of the following physical quantities: redshift, halo mass, stellar mass and stellar-to-halo mass ratio. Our model is highly idealized, with other sources of scatter likely to arise as more physics is included. Thus, our test is whether a model can produce scatter lower than observational bounds, leaving room for other sources. Recent measurements find σlog M* = 0.16 dex for 1011 M⊙ galaxies. Under the assumption that the threshold is constant with time, such a low value of σlog M* rules out all of these models with the exception of quenching by a stellar mass threshold. Most physical quantities, such as metallicity, will increase scatter if they are uncorrelated with halo formation history. Thus, to decrease the scatter of a given model, galaxy properties would correlate tightly with formation history, creating testable predictions for their clustering. Understanding why σlog M* is so small may be key to understanding the physics of galaxy formation.

The surface-to-volume ratio in thermal physics: from cheese cube physics to animal metabolism

NASA Astrophysics Data System (ADS)

Planinšič, Gorazd; Vollmer, Michael

2008-03-01

The surface-to-volume ratio is an important quantity in thermal physics. For example it governs the behaviour of heating or cooling of physical objects as a function of size like, e.g. cubes or spheres made of different material. The starting point in our paper is the simple physics problem of how cheese cubes of different sizes behave if heated either in a conventional oven or in a microwave oven. The outcome of these experiments depends on a balance between heating and cooling with the surface-to-volume ratio (S/V) as the key parameter. The role of (S/V) becomes most obvious in studying cooling curves of differently sized objects like cubes or spheres, alone. Besides problems in thermal physics, the surface-to-volume ratio has many important applications in biochemistry, chemistry and biology. It allows us to draw general conclusions concerning the thermal and mechanical properties of different-sized animals, in particular their metabolism. Hence, this topic offers rich contexts for interdisciplinary teaching. An example presented in this paper starts in physics while studying thermal properties of cheese cubes and ends up in biology by discussing the differences in food intake of animals from small mice to huge elephants.

Comparative Assessment of Physical and Social Determinants of Water Quantity and Water Quality Concerns

NASA Astrophysics Data System (ADS)

Gunda, T.; Hornberger, G. M.

2017-12-01

Concerns over water resources have evolved over time, from physical availability to economic access and recently, to a more comprehensive study of "water security," which is inherently interdisciplinary because a secure water system is influenced by and affects both physical and social components. The concept of water security carries connotations of both an adequate supply of water as well as water that meets certain quality standards. Although the term "water security" has many interpretations in the literature, the research field has not yet developed a synthetic analysis of water security as both a quantity (availability) and quality (contamination) issue. Using qualitative comparative and multi-regression analyses, we evaluate the primary physical and social factors influencing U.S. states' water security from a quantity perspective and from a quality perspective. Water system characteristics are collated from academic and government sources and include access/use, governance, and sociodemographic, and ecosystem metrics. Our analysis indicates differences in variables driving availability and contamination concerns; for example, climate is a more significant determinant in water quantity-based security analyses than in water quality-based security analyses. We will also discuss coevolution of system traits and the merits of constructing a robust water security index based on the relative importance of metrics from our analyses. These insights will improve understanding of the complex interactions between quantity and quality aspects and thus, overall security of water systems.

Assessing students' ability to solve introductory physics problems using integrals in symbolic and graphical representations

NASA Astrophysics Data System (ADS)

Khan, Neelam; Hu, Dehui; Nguyen, Dong-Hai; Rebello, N. Sanjay

2012-02-01

Integration is widely used in physics in electricity and magnetism (E&M), as well as in mechanics, to calculate physical quantities from other non-constant quantities. We designed a survey to assess students' ability to apply integration to physics problems in introductory physics. Each student was given a set of eight problems, and each set of problems had two different versions; one consisted of symbolic problems and the other graphical problems. The purpose of this study was to investigate students' strategies for solving physics problems that use integrals in first and second-semester calculus-based physics. Our results indicate that most students had difficulty even recognizing that an integral is needed to solve the problem.

An Algebraic Approach to Unital Quantities and their Measurement

NASA Astrophysics Data System (ADS)

Domotor, Zoltan; Batitsky, Vadim

2016-06-01

The goals of this paper fall into two closely related areas. First, we develop a formal framework for deterministic unital quantities in which measurement unitization is understood to be a built-in feature of quantities rather than a mere annotation of their numerical values with convenient units. We introduce this idea within the setting of certain ordered semigroups of physical-geometric states of classical physical systems. States are assumed to serve as truth makers of metrological statements about quantity values. A unital quantity is presented as an isomorphism from the target system's ordered semigroup of states to that of positive reals. This framework allows us to include various derived and variable quantities, encountered in engineering and the natural sciences. For illustration and ease of presentation, we use the classical notions of length, time, electric current and mean velocity as primordial examples. The most important application of the resulting unital quantity calculus is in dimensional analysis. Second, in evaluating measurement uncertainty due to the analog-to-digital conversion of the measured quantity's value into its measuring instrument's pointer quantity value, we employ an ordered semigroup framework of pointer states. Pointer states encode the measuring instrument's indiscernibility relation, manifested by not being able to distinguish the measured system's topologically proximal states. Once again, we focus mainly on the measurement of length and electric current quantities as our motivating examples. Our approach to quantities and their measurement is strictly state-based and algebraic in flavor, rather than that of a representationalist-style structure-preserving numerical assignment.

Can the Lorenz-Gauge Potentials Be Considered Physical Quantities?

ERIC Educational Resources Information Center

Heras, Jose A.; Fernandez-Anaya, Guillermo

2010-01-01

Two results support the idea that the scalar and vector potentials in the Lorenz gauge can be considered to be physical quantities: (i) they separately satisfy the properties of causality and propagation at the speed of light and do not imply spurious terms and (ii) they can naturally be written in a manifestly covariant form. In this paper we…

Social Relationships and Health: A Flashpoint for Health Policy

PubMed Central

Umberson, Debra; Montez, Jennifer Karas

2011-01-01

Social relationships—both quantity and quality—affect mental health, health behavior, physical health, and mortality risk. Sociologists have played a central role in establishing the link between social relationships and health outcomes, identifying explanations for this link, and discovering social variation (e.g., by gender and race) at the population level. Studies show that social relationships have short- and long-term effects on health, for better and for worse, and that these effects emerge in childhood and cascade throughout life to foster cumulative advantage or disadvantage in health. This article describes key research themes in the study of social relationships and health, and it highlights policy implications suggested by this research. PMID:20943583

A general methodology for population analysis

NASA Astrophysics Data System (ADS)

Lazov, Petar; Lazov, Igor

2014-12-01

For a given population with N - current and M - maximum number of entities, modeled by a Birth-Death Process (BDP) with size M+1, we introduce utilization parameter ρ, ratio of the primary birth and death rates in that BDP, which, physically, determines (equilibrium) macrostates of the population, and information parameter ν, which has an interpretation as population information stiffness. The BDP, modeling the population, is in the state n, n=0,1,…,M, if N=n. In presence of these two key metrics, applying continuity law, equilibrium balance equations concerning the probability distribution pn, n=0,1,…,M, of the quantity N, pn=Prob{N=n}, in equilibrium, and conservation law, and relying on the fundamental concepts population information and population entropy, we develop a general methodology for population analysis; thereto, by definition, population entropy is uncertainty, related to the population. In this approach, what is its essential contribution, the population information consists of three basic parts: elastic (Hooke's) or absorption/emission part, synchronization or inelastic part and null part; the first two parts, which determine uniquely the null part (the null part connects them), are the two basic components of the Information Spectrum of the population. Population entropy, as mean value of population information, follows this division of the information. A given population can function in information elastic, antielastic and inelastic regime. In an information linear population, the synchronization part of the information and entropy is absent. The population size, M+1, is the third key metric in this methodology. Namely, right supposing a population with infinite size, the most of the key quantities and results for populations with finite size, emerged in this methodology, vanish.

Physical Uncertainty Bounds (PUB)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vaughan, Diane Elizabeth; Preston, Dean L.

2015-03-19

This paper introduces and motivates the need for a new methodology for determining upper bounds on the uncertainties in simulations of engineered systems due to limited fidelity in the composite continuum-level physics models needed to simulate the systems. We show that traditional uncertainty quantification methods provide, at best, a lower bound on this uncertainty. We propose to obtain bounds on the simulation uncertainties by first determining bounds on the physical quantities or processes relevant to system performance. By bounding these physics processes, as opposed to carrying out statistical analyses of the parameter sets of specific physics models or simply switchingmore » out the available physics models, one can obtain upper bounds on the uncertainties in simulated quantities of interest.« less

Order and Value: Transitioning to Integers

ERIC Educational Resources Information Center

Bofferding, Laura

2014-01-01

As students progress from working with whole numbers to working with integers, they must wrestle with the big ideas of number values and order. Using objects to show positive quantities is easy, but no physical negative quantities exist. Therefore, when talking about integers, the author refers to number values instead of number quantities. The…

Evidence for Direct Retrieval of Relative Quantity Information in a Quantity Judgment Task: Decimals, Integers, and the Role of Physical Similarity

ERIC Educational Resources Information Center

Cohen, Dale J.

2010-01-01

Participants' reaction times (RTs) in numerical judgment tasks in which one must determine which of 2 numbers is greater generally follow a monotonically decreasing function of the numerical distance between the two presented numbers. Here, I present 3 experiments in which the relative influences of numerical distance and physical similarity are…

Pattern of mathematic representation ability in magnetic electricity problem

NASA Astrophysics Data System (ADS)

Hau, R. R. H.; Marwoto, P.; Putra, N. M. D.

2018-03-01

The mathematic representation ability in solving magnetic electricity problem gives information about the way students understand magnetic electricity. Students have varied mathematic representation pattern ability in solving magnetic electricity problem. This study aims to determine the pattern of students' mathematic representation ability in solving magnet electrical problems.The research method used is qualitative. The subject of this study is the fourth semester students of UNNES Physics Education Study Program. The data collection is done by giving a description test that refers to the test of mathematical representation ability and interview about field line topic and Gauss law. The result of data analysis of student's mathematical representation ability in solving magnet electric problem is categorized into high, medium and low category. The ability of mathematical representations in the high category tends to use a pattern of making known and asked symbols, writing equations, using quantities of physics, substituting quantities into equations, performing calculations and final answers. The ability of mathematical representation in the medium category tends to use several patterns of writing the known symbols, writing equations, using quantities of physics, substituting quantities into equations, performing calculations and final answers. The ability of mathematical representations in the low category tends to use several patterns of making known symbols, writing equations, substituting quantities into equations, performing calculations and final answer.

A study of the use of abstract types for the representation of engineering units in integration and test applications

NASA Technical Reports Server (NTRS)

Johnson, Charles S.

1986-01-01

Physical quantities using various units of measurement can be well represented in Ada by the use of abstract types. Computation involving these quantities (electric potential, mass, volume) can also automatically invoke the computation and checking of some of the implicitly associable attributes of measurements. Quantities can be held internally in SI units, transparently to the user, with automatic conversion. Through dimensional analysis, the type of the derived quantity resulting from a computation is known, thereby allowing dynamic checks of the equations used. The impact of the possible implementation of these techniques in integration and test applications is discussed. The overhead of computing and transporting measurement attributes is weighed against the advantages gained by their use. The construction of a run time interpreter using physical quantities in equations can be aided by the dynamic equation checks provided by dimensional analysis. The effects of high levels of abstraction on the generation and maintenance of software used in integration and test applications are also discussed.

On the Concepts of Quantity and Quality in the History of Western Thought

ERIC Educational Resources Information Center

Campbell, Stephen R.

2004-01-01

This paper charts a cognitive history of the concepts of quantity and quality from three inter-related and inter-dependent perspectives of mathematics, logic, and physics. In so doing, other notions associated with the evolution of these concepts are identified and explicated. It is argued that the concepts of quantity and quality, considered in…

Quantity, Quality, and Satisfaction with Mentoring: What Matters Most?

ERIC Educational Resources Information Center

Xu, Xiaohong; Payne, Stephanie C.

2014-01-01

According to Kram's mentor role theory, satisfaction with mentoring and mentorship quality are key indicators of effective and successful mentoring. We contribute to mentoring research by demonstrating the relative importance of mentorship quantity, mentorship quality, and satisfaction with mentoring to the prediction of job satisfaction,…

The principle of ‘maximum energy dissipation’: a novel thermodynamic perspective on rapid water flow in connected soil structures

PubMed Central

Zehe, Erwin; Blume, Theresa; Blöschl, Günter

2010-01-01

Preferential flow in biological soil structures is of key importance for infiltration and soil water flow at a range of scales. In the present study, we treat soil water flow as a dissipative process in an open non-equilibrium thermodynamic system, to better understand this key process. We define the chemical potential and Helmholtz free energy based on soil physical quantities, parametrize a physically based hydrological model based on field data and simulate the evolution of Helmholtz free energy in a cohesive soil with different populations of worm burrows for a range of rainfall scenarios. The simulations suggest that flow in connected worm burrows allows a more efficient redistribution of water within the soil, which implies a more efficient dissipation of free energy/higher production of entropy. There is additional evidence that the spatial pattern of worm burrow density at the hillslope scale is a major control of energy dissipation. The pattern typically found in the study is more efficient in dissipating energy/producing entropy than other patterns. This is because upslope run-off accumulates and infiltrates via the worm burrows into the dry soil in the lower part of the hillslope, which results in an overall more efficient dissipation of free energy. PMID:20368256

The role of soil communities in improving ecosystem services in organic farming

NASA Astrophysics Data System (ADS)

Zandbergen, Jelmer; Koorneef, Guusje; Veen, Cees; Schrama, Jan; van der Putten, Wim

2017-04-01

Worldwide soil fertility decreases and it is generally believed that organic matter (OM) addition to agricultural soils can improve soil properties leading to beneficial ecosystem services. However, it remains unknown under which conditions and how fast biotic, physical and chemical soil properties respond to varying quality and quantity of OM inputs. Therefore, the aims of this research project are (1) to unravel biotic, physical and chemical responses of soils to varying quantity and quality of OM addition; and (2) to understand how we can accelerate the response of soils in order to improve beneficial soil ecosystem services faster. The first step in our research project is to determine how small-scale spatio-temporal patterns in soil biotic, physical and chemical properties relate to crop production and quality. To do this we combine field measurements on soil properties with remote and proximate sensing measures on crop development and yield in a long-term farming systems experiment in the Netherlands (Vredepeel). We hypothesize that spatio-temporal variation in crop development and yield are strongly related to spatio-temporal variation in soil parameters. In the second step of our project we will use this information to identify biological interactions underlying improving soil functions in response to OM addition over time. We will specifically focus on the role of soil communities in driving nutrient cycling, disease suppression and the formation of soil structure, all crucial elements of key soil services in agricultural soils. The knowledge that will be generated in our project can be used to detect specific organic matter qualities that support the underlying ecological processes to accelerate the transition towards improved soil functioning thereby governing enhanced crop yields.

Quantum Physics and Mathematical Debates Concerning the Problem of the Ontological Priority between Continuous Quantity and Discrete Quantity

NASA Astrophysics Data System (ADS)

Pin, Victor Gómez

In his book about the Categories (that is about the ultimate elements of classification and order), in the chapter concerning the quantity (IV, 20) Aristotle says that this concept recovers two kinds of modalities: the discrete quantity and the continuous quantity and he gives as examples the number for the first one; line, surface, solid, times and space for the second one. The main philosophical problem raised by this text is to determine which of the two modalities of the quantity has the ontological priority over the other (given two concepts A and B, we assume that A has ontological priority over B if every entity that possesses the quality B possesses necessarily the quality A). The problem is magnified by the fact that space, which in some part of Aristotle's Physics is mentioned not only as a category properly speaking but even as the main category whose power can be amazing, is in the evoked text of the Categories's Book reduced to expression of the continuum, and sharing this condition with time. In this matter the controversy is constant through the common history of Science and Philosophy.

Black Hole Safari: Tracking Populations and Hunting Big Game

NASA Astrophysics Data System (ADS)

McConnell, N. J.

2013-10-01

Understanding the physical connection, or lack thereof, between the growth of galaxies and supermassive black holes is a key challenge in extragalactic astronomy. Dynamical studies of nearby galaxies are building a census of black hole masses across a broad range of galaxy types and uncovering statistical correlations between galaxy bulge properties and black hole masses. These local correlations provide a baseline for studying galaxies and black holes at higher redshifts. Recent measurements have probed the extremes of the supermassive black hole population and introduced surprises that challenge simple models of black hole and galaxy co-evolution. Future advances in the quality and quantity of dynamical black hole mass measurements will shed light upon the growth of massive galaxies and black holes in different cosmic environments.

Optofluidic Cell Selection from Complex Microbial Communities for Single-Genome Analysis

PubMed Central

Landry, Zachary C.; Giovanonni, Stephen J.; Quake, Stephen R.; Blainey, Paul C.

2013-01-01

Genetic analysis of single cells is emerging as a powerful approach for studies of heterogeneous cell populations. Indeed, the notion of homogeneous cell populations is receding as approaches to resolve genetic and phenotypic variation between single cells are applied throughout the life sciences. A key step in single-cell genomic analysis today is the physical isolation of individual cells from heterogeneous populations, particularly microbial populations, which often exhibit high diversity. Here, we detail the construction and use of instrumentation for optical trapping inside microfluidic devices to select individual cells for analysis by methods including nucleic acid sequencing. This approach has unique advantages for analyses of rare community members, cells with irregular morphologies, small quantity samples, and studies that employ advanced optical microscopy. PMID:24060116

High-throughput density-functional perturbation theory phonons for inorganic materials

NASA Astrophysics Data System (ADS)

Petretto, Guido; Dwaraknath, Shyam; P. C. Miranda, Henrique; Winston, Donald; Giantomassi, Matteo; van Setten, Michiel J.; Gonze, Xavier; Persson, Kristin A.; Hautier, Geoffroy; Rignanese, Gian-Marco

2018-05-01

The knowledge of the vibrational properties of a material is of key importance to understand physical phenomena such as thermal conductivity, superconductivity, and ferroelectricity among others. However, detailed experimental phonon spectra are available only for a limited number of materials, which hinders the large-scale analysis of vibrational properties and their derived quantities. In this work, we perform ab initio calculations of the full phonon dispersion and vibrational density of states for 1521 semiconductor compounds in the harmonic approximation based on density functional perturbation theory. The data is collected along with derived dielectric and thermodynamic properties. We present the procedure used to obtain the results, the details of the provided database and a validation based on the comparison with experimental data.

Origin of the spike-timing-dependent plasticity rule

NASA Astrophysics Data System (ADS)

Cho, Myoung Won; Choi, M. Y.

2016-08-01

A biological synapse changes its efficacy depending on the difference between pre- and post-synaptic spike timings. Formulating spike-timing-dependent interactions in terms of the path integral, we establish a neural-network model, which makes it possible to predict relevant quantities rigorously by means of standard methods in statistical mechanics and field theory. In particular, the biological synaptic plasticity rule is shown to emerge as the optimal form for minimizing the free energy. It is further revealed that maximization of the entropy of neural activities gives rise to the competitive behavior of biological learning. This demonstrates that statistical mechanics helps to understand rigorously key characteristic behaviors of a neural network, thus providing the possibility of physics serving as a useful and relevant framework for probing life.

TIMEKEEPING IN THE AMERICAS.

PubMed

López, J M; Lombardi, M A

Time and its measurement belong to the most fundamental core of physics, and many scientific and technological advances are directly or indirectly related to time measurements. Timekeeping is essential to everyday life, and thus is the most measured physical quantity in modern societies. Time can also be measured with less uncertainty and more resolution than any other physical quantity. The measurement of time is of the utmost importance for many applications, including: global navigation satellite systems, communications networks, electric power generation, astronomy, electronic commerce, and national defense and security. This paper discusses how time is kept, coordinated, and disseminated in the Americas.

Timekeeping in the Americas

NASA Astrophysics Data System (ADS)

López, J. M.; Lombardi, M. A.

2015-10-01

Time and its measurement belong to the most fundamental core of physics, and many scientific and technological advances are directly or indirectly related to time measurements. Timekeeping is essential to everyday life, and thus is the most measured physical quantity in modern societies. Time can also be measured with less uncertainty and more resolution than any other physical quantity. The measurement of time is of the utmost importance for many applications, including: global navigation satellite systems, communications networks, electric power generation, astronomy, electronic commerce, and national defense and security. This paper discusses how time is kept, coordinated, and disseminated in the Americas.

TIMEKEEPING IN THE AMERICAS

PubMed Central

López, J. M.; Lombardi, M. A.

2016-01-01

Time and its measurement belong to the most fundamental core of physics, and many scientific and technological advances are directly or indirectly related to time measurements. Timekeeping is essential to everyday life, and thus is the most measured physical quantity in modern societies. Time can also be measured with less uncertainty and more resolution than any other physical quantity. The measurement of time is of the utmost importance for many applications, including: global navigation satellite systems, communications networks, electric power generation, astronomy, electronic commerce, and national defense and security. This paper discusses how time is kept, coordinated, and disseminated in the Americas. PMID:26973371

Physical activity and exercise promotion and prescription in undergraduate physiotherapy education: content analysis of Irish curricula.

PubMed

O'Donoghue, Grainne; Doody, Catherine; Cusack, Tara

2011-06-01

Overwhelming evidence shows that physical activity and exercise promotion and prescription are effective in preventing and managing numerous chronic conditions. With physiotherapists commonly referred to as 'exercise prescription experts', an in-depth knowledge of exercise promotion and prescription is assumed. However, to date, no information exists about what is or should be included in terms of undergraduate physiotherapy physical activity and exercise education, nor whether the content prepares graduates to be exercise experts for contemporary practice. To provide an accurate, contemporary picture of physical activity and exercise promotion and prescription content within Irish undergraduate physiotherapy curricula. Content analysis was used to explore physical activity and exercise inclusion within four of the five programmes in Ireland. Seven categories were generated. Frequency analysis for each category was used to provide a guide to the extensiveness of physical activity and exercise promotion and prescription content. All curricula included varying quantities of basic exercise science and exercise testing and prescription. Physical activity and exercise promotion and prescription for conditions routinely referred to physiotherapy, such as cardio respiratory disease, were well represented. Three key areas were identified as being absent or needing further emphasis: physical activity/exercise for public health, strategies for changing physical activity behaviour, and physical activity/exercise for lifestyle-related diseases. Results indicate a strong need for re-evaluation of physical activity and exercise education in Irish physiotherapy curricula. There is a lack of explicit exercise content in relation to public health and lifestyle-related disease. Copyright © 2010 Chartered Society of Physiotherapy. Published by Elsevier Ltd. All rights reserved.

A thermodynamically consistent model for granular-fluid mixtures considering pore pressure evolution and hypoplastic behavior

NASA Astrophysics Data System (ADS)

Hess, Julian; Wang, Yongqi

2016-11-01

A new mixture model for granular-fluid flows, which is thermodynamically consistent with the entropy principle, is presented. The extra pore pressure described by a pressure diffusion equation and the hypoplastic material behavior obeying a transport equation are taken into account. The model is applied to granular-fluid flows, using a closing assumption in conjunction with the dynamic fluid pressure to describe the pressure-like residual unknowns, hereby overcoming previous uncertainties in the modeling process. Besides the thermodynamically consistent modeling, numerical simulations are carried out and demonstrate physically reasonable results, including simple shear flow in order to investigate the vertical distribution of the physical quantities, and a mixture flow down an inclined plane by means of the depth-integrated model. Results presented give insight in the ability of the deduced model to capture the key characteristics of granular-fluid flows. We acknowledge the support of the Deutsche Forschungsgemeinschaft (DFG) for this work within the Project Number WA 2610/3-1.

The physical chemistry of Criegee intermediates in the gas phase

DOE PAGES

Osborn, David L.; Taatjes, Craig A.

2015-07-24

Here, carbonyl oxides, also known as Criegee intermediates, are key intermediates in both gas phase ozonolysis of unsaturated hydrocarbons in the troposphere and solution phase organic synthesis via ozonolysis. Although the study of Criegee intermediates in both arenas has a long history, direct studies in the gas phase have only recently become possible through new methods of generating stabilised Criegee intermediates in sufficient quantities. This advance has catalysed a large number of new experimental and theoretical investigations of Criegee intermediate chemistry. In this article we review the physical chemistry of Criegee intermediates, focusing on their molecular structure, spectroscopy, unimolecular andmore » bimolecular reactions. These recent results have overturned conclusions from some previous studies, while confirming others, and have clarified areas of investigation that will be critical targets for future studies. In addition to expanding our fundamental understanding of Criegee intermediates, the rapidly expanding knowledge base will support increasingly predictive models of their impacts on society.« less

Black holes in loop quantum gravity.

PubMed

Perez, Alejandro

2017-12-01

This is a review of results on black hole physics in the context of loop quantum gravity. The key feature underlying these results is the discreteness of geometric quantities at the Planck scale predicted by this approach to quantum gravity. Quantum discreteness follows directly from the canonical quantization prescription when applied to the action of general relativity that is suitable for the coupling of gravity with gauge fields, and especially with fermions. Planckian discreteness and causal considerations provide the basic structure for the understanding of the thermal properties of black holes close to equilibrium. Discreteness also provides a fresh new look at more (at the moment) speculative issues, such as those concerning the fate of information in black hole evaporation. The hypothesis of discreteness leads, also, to interesting phenomenology with possible observational consequences. The theory of loop quantum gravity is a developing program; this review reports its achievements and open questions in a pedagogical manner, with an emphasis on quantum aspects of black hole physics.

Separation of the Carotenoid Bixin from Annatto Seeds Using Thin-Layer and Column Chromatography

ERIC Educational Resources Information Center

McCullagh, James V.; Ramos, Nicholas

2008-01-01

In this experiment the carotenoid bixin is isolated from annatto ("Bixa orellana") seeds using column chromatography. The experiment has several key advantages over previous pigment separation experiments. First, unlike other experiments significant quantities of the carotenoid (typically 20 to 25 mg) can be isolated from small quantities of plant…

The definitions of information and meaning two possible boundaries between physics and biology.

PubMed

Barbieri, Marcello

2004-01-01

The standard approach to the definition of the physical quantities has not produced satisfactory results with the concepts of information and meaning. In the case of information we have at least two unrelated definitions, while in the case of meaning we have no definition at all. Here it is shown that both information and meaning can be defined by operative procedures, but it is also pointed out that we need to recognize them as a new type of natural entities. They are not quantities (neither fundamental nor derived) because they cannot be measured, and they are not qualities because are not subjective features. Here it is proposed to call them nominable entities, i.e., entities which can be specified only by naming their components in their natural order. If the genetic code is not a linguistic metaphor but a reality, we must conclude that information and meaning are real natural entities, and now we must also conclude that they are not equivalent to the quantities and qualities of our present theoretical framework. This gives us two options. One is to extend the definition of physics and say that the list of its fundamental entities must include information and meaning. The other is to say that physics is the science of quantities only, and in this case information and meaning become the exclusive province of biology. The boundary between physics and biology, in short, is a matter of convention, but the existence of information and meaning is not. We can decide to study them in the framework of an extended physics or in a purely biological framework, but we cannot avoid studying them for what they are, i.e., as fundamental components of the fabric of Nature.

Transfer entropy in physical systems and the arrow of time

NASA Astrophysics Data System (ADS)

Spinney, Richard E.; Lizier, Joseph T.; Prokopenko, Mikhail

2016-08-01

Recent developments have cemented the realization that many concepts and quantities in thermodynamics and information theory are shared. In this paper, we consider a highly relevant quantity in information theory and complex systems, the transfer entropy, and explore its thermodynamic role by considering the implications of time reversal upon it. By doing so we highlight the role of information dynamics on the nuanced question of observer perspective within thermodynamics by relating the temporal irreversibility in the information dynamics to the configurational (or spatial) resolution of the thermodynamics. We then highlight its role in perhaps the most enduring paradox in modern physics, the manifestation of a (thermodynamic) arrow of time. We find that for systems that process information such as those undergoing feedback, a robust arrow of time can be formulated by considering both the apparent physical behavior which leads to conventional entropy production and the information dynamics which leads to a quantity we call the information theoretic arrow of time. We also offer an interpretation in terms of optimal encoding of observed physical behavior.

The Importance of Measurement Data Spacing

ERIC Educational Resources Information Center

Seixas, T. M.; da Silva, M. A. Salgueiro

2015-01-01

When conducting experiments involving the measurement of physically related quantities, choosing an appropriate spacing for the experimental independent variable is a crucial procedure whose consequences may go beyond data graphical visualization. This is particularly true if the measured quantities are nonlinearly related and experimental errors…

Dimensional Analysis Applied to Electricity and Mechanics.

ERIC Educational Resources Information Center

Thomas, G.

1979-01-01

Suggests an alternative system of measurement to be used in engineering, which provides theoretical insight and leads to definitions of dual and analogous physical quantities. The system is based on the notion that the dimensional product of three fundamental quantities should be energy. (GA)

Influences of management of Southern forests on water quantity and quality

Treesearch

Ge Sun; Mark Riedel; Rhett Jackson; Randy Kolka; Devendra Amatya; Jim Shepard

2004-01-01

Water is a key output of southern forests and is critical to other processes, functions, and values of forest ecosystems. This chapter synthesizes published literature about the effects of forest management practices on water quantity and water quality across the Southern United States region. We evaluate the influences of forest management at different temporal and...

Understanding and manipulating the RF fields at high field MRI

PubMed Central

Ibrahim, Tamer S.; Hue, YiK-Kiong; Tang, Lin

2015-01-01

This paper presents a complete overview of the electromagnetics (radiofrequency aspect) of MRI at low and high fields. Using analytical formulations, numerical modeling (computational electromagnetics), and ultrahigh field imaging experiments, the physics that impacts the electromagnetic quantities associated with MRI, namely (1) the transmit field, (2) receive field, and (3) total electromagnetic power absorption, is analyzed. The physical interpretation of the above-mentioned quantities is investigated by electromagnetic theory, to understand ‘What happens, in terms of electromagnetics, when operating at different static field strengths?’ Using experimental studies and numerical simulations, this paper also examines the physical and technological feasibilities by which all or any of these specified electromagnetic quantities can be manipulated through techniques such as B1 shimming (phased array excitation) and signal combination using a receive array in order to advance MRI at high field strengths. Pertinent to this subject and with highly coupled coils operating at 7 T, this paper also presents the first phantom work on B1 shimming without B1 measurements. PMID:19621335

27 CFR 46.202 - Physical inventory requirements.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 27 Alcohol, Tobacco Products and Firearms 2 2010-04-01 2010-04-01 false Physical inventory... Cigarette Tubes Held for Sale on April 1, 2009 Inventories § 46.202 Physical inventory requirements. The dealer's physical inventory must result in a written record of: (a) The quantity and type of each article...

27 CFR 46.202 - Physical inventory requirements.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 27 Alcohol, Tobacco Products and Firearms 2 2013-04-01 2013-04-01 false Physical inventory... Cigarette Tubes Held for Sale on April 1, 2009 Inventories § 46.202 Physical inventory requirements. The dealer's physical inventory must result in a written record of: (a) The quantity and type of each article...

27 CFR 46.202 - Physical inventory requirements.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 27 Alcohol, Tobacco Products and Firearms 2 2011-04-01 2011-04-01 false Physical inventory... Cigarette Tubes Held for Sale on April 1, 2009 Inventories § 46.202 Physical inventory requirements. The dealer's physical inventory must result in a written record of: (a) The quantity and type of each article...

27 CFR 46.202 - Physical inventory requirements.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 27 Alcohol, Tobacco Products and Firearms 2 2014-04-01 2014-04-01 false Physical inventory... Cigarette Tubes Held for Sale on April 1, 2009 Inventories § 46.202 Physical inventory requirements. The dealer's physical inventory must result in a written record of: (a) The quantity and type of each article...

27 CFR 46.202 - Physical inventory requirements.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 27 Alcohol, Tobacco Products and Firearms 2 2012-04-01 2011-04-01 true Physical inventory... Cigarette Tubes Held for Sale on April 1, 2009 Inventories § 46.202 Physical inventory requirements. The dealer's physical inventory must result in a written record of: (a) The quantity and type of each article...

Lattice QCD and physics beyond the Standar Model: an experimentalist perspective

NASA Astrophysics Data System (ADS)

Artuso, Marina

2017-01-01

The new frontier in elementary particle physics is to find evidence for new physics that may lead to a deeper understanding of observations such as the baryon-antibaryon asymmetry of the universe, mass hierarchy, dark matter, or dark energy to name a few. Flavor physics provides a wealth of opportunities to find such signatures, and a vast body of data taken at e+e- b-factories and at hadron machines has provided valuable information, and a few tantalizing ``tensions'' with respect to the Standard Model predictions. While the window for new physics is still open, the chance that its manifestations will be subtle is very real. A vibrant experimental program is ongoing, and significant upgrades, such as the upgraded LHCb experiment at LHC and Belle 2 at KEKb, are imminent. One of the challenges in extracting new physics from flavor physics data is the need to relate observed hadron decays to fundamental particles and interactions. The continuous improvement of Lattice QCD predictions is a key element to achieve success in this quest. Improvements in algorithms and hardware have led to predictions of increasing precision on several fundamental matrix elements, and the continuous breaking of new grounds, thus allowing a broader spectrum of measurements to become relevant to this quest. An important aspect of the experiment-lattice synergy is a comparison between lattice predictions with experiment for a variety of hadronic quantities. This talk summarizes current synergies between lattice QCD theory and flavor physics experiments, and gives some highlights of expectations from future upgrades. this work was supported by NSF.

Physical Activity During Recess Outdoors and Indoors Among Urban Public School Students, St. Louis, Missouri, 2010–2011

PubMed Central

Tran, Irene; Clark, B. Ruth

2013-01-01

We measured the quantity and intensity of physical activity in 106 urban public school students during recess outdoors, recess indoors in the gym, and recess indoors in the classroom. Students in grades 2 through 5 wore accelerometer pedometers for an average of 6.2 (standard deviation [SD], 1.4) recess periods over 8 weeks; a subsample of 26 also wore heart rate monitors. We determined, on the basis of 655 recess observations, that outdoor recess enabled more total steps per recess period (P < .0001), more steps in moderate-to-vigorous physical activity (P < .0001), and higher heart rates than recess in the gym or classroom. To maximize physical activity quantity and intensity, school policies should promote outdoor recess. PMID:24262028

Qualitative methods in quantum theory

DOE Office of Scientific and Technical Information (OSTI.GOV)

Migdal, A.B.

The author feels that the solution of most problems in theoretical physics begins with the application of qualitative methods - dimensional estimates and estimates made from simple models, the investigation of limiting cases, the use of the analytic properties of physical quantities, etc. This book proceeds in this spirit, rather than in a formal, mathematical way with no traces of the sweat involved in the original work left to show. The chapters are entitled Dimensional and model approximations, Various types of perturbation theory, The quasi-classical approximation, Analytic properties of physical quantities, Methods in the many-body problem, and Qualitative methods inmore » quantum field theory. Each chapter begins with a detailed introduction, in which the physical meaning of the results obtained in that chapter is explained in a simple way. 61 figures. (RWR)« less

The Herschel view of GAS in Protoplanetary Systems (GASPS). First comparisons with a large grid of models

NASA Astrophysics Data System (ADS)

Pinte, C.; Woitke, P.; Ménard, F.; Duchêne, G.; Kamp, I.; Meeus, G.; Mathews, G.; Howard, C. D.; Grady, C. A.; Thi, W.-F.; Tilling, I.; Augereau, J.-C.; Dent, W. R. F.; Alacid, J. M.; Andrews, S.; Ardila, D. R.; Aresu, G.; Barrado, D.; Brittain, S.; Ciardi, D. R.; Danchi, W.; Eiroa, C.; Fedele, D.; de Gregorio-Monsalvo, I.; Heras, A.; Huelamo, N.; Krivov, A.; Lebreton, J.; Liseau, R.; Martin-Zaïdi, C.; Mendigutía, I.; Montesinos, B.; Mora, A.; Morales-Calderon, M.; Nomura, H.; Pantin, E.; Pascucci, I.; Phillips, N.; Podio, L.; Poelman, D. R.; Ramsay, S.; Riaz, B.; Rice, K.; Riviere-Marichalar, P.; Roberge, A.; Sandell, G.; Solano, E.; Vandenbussche, B.; Walker, H.; Williams, J. P.; White, G. J.; Wright, G.

2010-07-01

The Herschel GASPS key program is a survey of the gas phase of protoplanetary discs, targeting 240 objects which cover a large range of ages, spectral types, and disc properties. To interpret this large quantity of data and initiate self-consistent analyses of the gas and dust properties of protoplanetary discs, we have combined the capabilities of the radiative transfer code MCFOST with the gas thermal balance and chemistry code ProDiMo to compute a grid of ≈300 000 disc models (DENT). We present a comparison of the first Herschel/GASPS line and continuum data with the predictions from the DENT grid of models. Our objective is to test some of the main trends already identified in the DENT grid, as well as to define better empirical diagnostics to estimate the total gas mass of protoplanetary discs. Photospheric UV radiation appears to be the dominant gas-heating mechanism for Herbig stars, whereas UV excess and/or X-rays emission dominates for T Tauri stars. The DENT grid reveals the complexity in the analysis of far-IR lines and the difficulty to invert these observations into physical quantities. The combination of Herschel line observations with continuum data and/or with rotational lines in the (sub-)millimetre regime, in particular CO lines, is required for a detailed characterisation of the physical and chemical properties of circumstellar discs. Herschel is an ESA space observatory with science instruments provided by European-led Principal Investigator consortia and with important participation from NASA.

Peak leg muscle power, peak VO2 and its correlates with physical activity in 57 to 70-year-old women.

PubMed

Boussuge, P-Y; Rance, M; Bedu, M; Duche, P; Praagh, E Van

2006-01-01

The two aims of this study were first to measure short-term muscle power (STMP) by means of a cycling force-velocity test (cycling peak power: CPP) and a vertical jump test (jumping peak performance: JPP) and second, to examine the relationships between physical activity (PA) level, peak oxygen uptake (peak VO2) and STMP in healthy elderly women. Twenty-three independent community-dwelling elderly women (mean age: 64+/-4.4) performed on separate days, a peak oxygen uptake test on cycle ergometer, a cycling force-velocity test and a vertical jump test. A questionnaire (QUANTAP) was used to assess lifespan exercise habits. Four indices expressed in kJ day(-1) kg(-1) were calculated. Two indices represented average past PA level: 1/quantity of habitual physical activity (QHPA), 2/quantity of sports activities (QSA). Two indices represented the actual PA level: 3/actual quantity of habitual physical activity (AQHPA), 4/actual quantity of sports activities (AQSA). CPP (6.3+/-1.2 W kg(-1)) was closely correlated to JPP (14.8+/-3.4 cm) (r=0.80, P<0.001). AQHPA and AQSA were only positively associated with peak VO2 (ml min(-1) kg(-1)) (r=0.49; r=0.50, P<0.05, respectively). Past PA level was not related to fitness measurements. Results show that in this population: (1) jumping peak performance was closely related to CPP measured in the laboratory; (2) the cardio-respiratory fitness was related to the actual habitual physical activity level; (3) only age and anthropometric variables explained the actual performances in multivariate analysis.

Astronomical reach of fundamental physics.

PubMed

Burrows, Adam S; Ostriker, Jeremiah P

2014-02-18

Using basic physical arguments, we derive by dimensional and physical analysis the characteristic masses and sizes of important objects in the universe in terms of just a few fundamental constants. This exercise illustrates the unifying power of physics and the profound connections between the small and the large in the cosmos we inhabit. We focus on the minimum and maximum masses of normal stars, the corresponding quantities for neutron stars, the maximum mass of a rocky planet, the maximum mass of a white dwarf, and the mass of a typical galaxy. To zeroth order, we show that all these masses can be expressed in terms of either the Planck mass or the Chandrasekar mass, in combination with various dimensionless quantities. With these examples, we expose the deep interrelationships imposed by nature between disparate realms of the universe and the amazing consequences of the unifying character of physical law.

Astronomical reach of fundamental physics

PubMed Central

Burrows, Adam S.; Ostriker, Jeremiah P.

2014-01-01

Using basic physical arguments, we derive by dimensional and physical analysis the characteristic masses and sizes of important objects in the universe in terms of just a few fundamental constants. This exercise illustrates the unifying power of physics and the profound connections between the small and the large in the cosmos we inhabit. We focus on the minimum and maximum masses of normal stars, the corresponding quantities for neutron stars, the maximum mass of a rocky planet, the maximum mass of a white dwarf, and the mass of a typical galaxy. To zeroth order, we show that all these masses can be expressed in terms of either the Planck mass or the Chandrasekar mass, in combination with various dimensionless quantities. With these examples, we expose the deep interrelationships imposed by nature between disparate realms of the universe and the amazing consequences of the unifying character of physical law. PMID:24477692

Rotating black holes in the teleparallel equivalent of general relativity

NASA Astrophysics Data System (ADS)

Nashed, Gamal G. L.

2016-05-01

We derive set of solutions with flat transverse sections in the framework of a teleparallel equivalent of general relativity which describes rotating black holes. The singularities supported from the invariants of torsion and curvature are explained. We investigate that there appear more singularities in the torsion scalars than in the curvature ones. The conserved quantities are discussed using Einstein-Cartan geometry. The physics of the constants of integration is explained through the calculations of conserved quantities. These calculations show that there is a unique solution that may describe true physical black hole.

Algorithmic complexity of real financial markets

NASA Astrophysics Data System (ADS)

Mansilla, R.

2001-12-01

A new approach to the understanding of complex behavior of financial markets index using tools from thermodynamics and statistical physics is developed. Physical complexity, a quantity rooted in the Kolmogorov-Chaitin theory is applied to binary sequences built up from real time series of financial markets indexes. The study is based on NASDAQ and Mexican IPC data. Different behaviors of this quantity are shown when applied to the intervals of series placed before crashes and to intervals when no financial turbulence is observed. The connection between our results and the efficient market hypothesis is discussed.

Doing without dimensions

NASA Astrophysics Data System (ADS)

Spurgin, C. B.

1986-03-01

The author discusses the concept of dimensions of a physical quantity, and the relationship between derived units (expressed in terms of their base units) and the dimensions of the derived quantities. He calls for the replacement of 'dimensions' by base units in the GCE A-level syllabus and provides some recommendations to GCE examining boards.

75 FR 47494 - Implementation Guidance for Physical Protection of Byproduct Material; Category 1 and Category 2...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-08-06

... for Physical Protection of Byproduct Material; Category 1 and Category 2 Quantities of Radioactive... on the draft implementation guidance for proposed 10 CFR part 37 Physical Protection of Byproduct... proposed 10 CFR part 37, Physical Protection of Byproduct Material, specifically Category 1 and Category 2...

Physical Activity Practices in Elementary Schools and Associations with Physical Education Staffing and Training

ERIC Educational Resources Information Center

Turner, Lindsey; Johnson, Tyler G.; Slater, Sandy J.; Chaloupka, Frank J.

2014-01-01

Purpose: Authorities recommend that schools provide a variety of opportunities for students to obtain physical activity (PA) before, during, and after school. This study assessed the prevalence of several school PA practices--including measures of quantity and quality of physical education (PE)--in elementary schools and examined the associations…

General Relativity: Geometry Meets Physics

ERIC Educational Resources Information Center

Thomsen, Dietrick E.

1975-01-01

Observing the relationship of general relativity and the geometry of space-time, the author questions whether the rest of physics has geometrical explanations. As a partial answer he discusses current research on subatomic particles employing geometric transformations, and cites the existence of geometrical definitions of physical quantities such…

Piagetian conservation of discrete quantities in bonobos (Pan paniscus), chimpanzees (Pan troglodytes), and orangutans (Pongo pygmaeus).

PubMed

Suda, Chikako; Call, Josep

2005-10-01

This study investigated whether physical discreteness helps apes to understand the concept of Piagetian conservation (i.e. the invariance of quantities). Subjects were four bonobos, three chimpanzees, and five orangutans. Apes were tested on their ability to conserve discrete/continuous quantities in an over-conservation procedure in which two unequal quantities of edible rewards underwent various transformations in front of subjects. Subjects were examined to determine whether they could track the larger quantity of reward after the transformation. Comparison between the two types of conservation revealed that tests with bonobos supported the discreteness hypothesis. Bonobos, but neither chimpanzees nor orangutans, performed significantly better with discrete quantities than with continuous ones. The results suggest that at least bonobos could benefit from the discreteness of stimuli in their acquisition of conservation skills.

On physical scales of dark matter halos

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zemp, Marcel, E-mail: mzemp@pku.edu.cn

2014-09-10

It is common practice to describe formal size and mass scales of dark matter halos as spherical overdensities with respect to an evolving density threshold. Here, we critically investigate the evolutionary effects of several such commonly used definitions and compare them to the halo evolution within fixed physical scales as well as to the evolution of other intrinsic physical properties of dark matter halos. It is shown that, in general, the traditional way of characterizing sizes and masses of halos dramatically overpredicts the degree of evolution in the last 10 Gyr, especially for low-mass halos. This pseudo-evolution leads to themore » illusion of growth even though there are no major changes within fixed physical scales. Such formal size definitions also serve as proxies for the virialized region of a halo in the literature. In general, those spherical overdensity scales do not coincide with the virialized region. A physically more precise nomenclature would be to simply characterize them by their very definition instead of calling such formal size and mass definitions 'virial'. In general, we find a discrepancy between the evolution of the underlying physical structure of dark matter halos seen in cosmological structure formation simulations and pseudo-evolving formal virial quantities. We question the importance of the role of formal virial quantities currently ubiquitously used in descriptions, models, and relations that involve properties of dark matter structures. Concepts and relations based on pseudo-evolving formal virial quantities do not properly reflect the actual evolution of dark matter halos and lead to an inaccurate picture of the physical evolution of our universe.« less

Theory of the magnetic skyrmion glass

NASA Astrophysics Data System (ADS)

Hoshino, Shintaro; Nagaosa, Naoto

2018-01-01

Skyrmions and skyrmion crystal (SkX) discovered in chiral magnets show unique physical properties due to their nontrivial topology such as the stability against the annihilation and the motion driven by the ultralow current density, which can be advantageous for the device applications such as magnetic memories. Especially, the chiral dynamics, i.e., the velocity perpendicular to the force acting on a skyrmion, is a key to avoid the impurity potential and enhances its mobility. However, the collective pinning of SkX occurs by the disorder, which is crucial for its low energy properties. Here we study theoretically the low energy dynamics of SkX in the presence of disorder effects in terms of replica field theory, and reveal nonreciprocal collective modes and their electromagnetic responses along the direction of the external magnetic field. The physical quantities such as the relaxation rate of μ SR /NMR and the pinning frequency show a dramatic change associated with the topological phase transition from the helical state to SkX. These results provide a firm basis to explore the glassy state of SkX.

Intrepid: Exploring the NEA population with a Fleet of Highly Autonomous SmallSat explorers

NASA Astrophysics Data System (ADS)

Blacksberg, Jordana; Chesley, Steven R.; Ehlmann, Bethany; Raymond, Carol Anne

2017-10-01

The Intrepid mission concept calls for phased deployment of a fleet of small highly autonomous rendezvous spacecraft designed to characterize the evolution, structure and composition of dozens of Near-Earth Asteroids (NEAs). Intrepid represents a marked departure from conventional solar system exploration projects, where a single unique and complex spacecraft is typically directed to explore a single target body. In contrast, Intrepid relies on the deployment of a large number of autonomous spacecraft to provide redundancy and ensure that the project goals are achieved at a small fraction of the cost of typical missions.The Intrepid science goals are threefold: (1) to understand the evolutionary processes that govern asteroid physical, chemical and dynamical histories and relate these results to solar system origins and evolution; (2) to facilitate impactor deflection scenarios for planetary defense by statistically characterizing relevant asteroid physical properties; (3) to quantify the presence and extractability of potentially useful resources on a large sample of asteroids. To achieve these goals, the baseline architecture includes multiple modular instruments including cameras, spectrometers, radar sounders, and projectiles that could interact with the target asteroid. Key questions to be addressed are: what is the total quantity of water in each object? How is the water incorporated? Are organics present? What is the asteroid physical structure? How would the object respond to impact/deflection?We have begun development of a miniature infrared point spectrometer, a cornerstone of the Intrepid payload, covering both shortwave infrared (SWIR) and mid-infrared (MIR) spectral bands. The spectrometer is designed with a compact 2U form-factor, making it both relevant to Intrepid and implementable on a CubeSat. The combination of SWIR and MIR in a single integrated instrument would enable robust compositional interpretations from a single dataset combining both solar reflectance and thermal emission spectroscopy. These measurements would be crucial to determining the quantity and nature of water present.

Plasma Equilibrium Control in Nuclear Fusion Devices 2. Plasma Control in Magnetic Confinement Devices 2.1 Plasma Control in Tokamaks

NASA Astrophysics Data System (ADS)

Fukuda, Takeshi

The plasma control technique for use in large tokamak devices has made great developmental strides in the last decade, concomitantly with progress in the understanding of tokamak physics and in part facilitated by the substantial advancement in the computing environment. Equilibrium control procedures have thereby been established, and it has been pervasively recognized in recent years that the real-time feedback control of physical quantities is indispensable for the improvement and sustainment of plasma performance in a quasi-steady-state. Further development is presently undertaken to realize the “advanced plasma control” concept, where integrated fusion performance is achieved by the simultaneous feedback control of multiple physical quantities, combined with equilibrium control.

10 CFR 37.77 - Advance notification of shipment of category 1 quantities of radioactive material.

Code of Federal Regulations, 2014 CFR

2014-01-01

... Policy, Office of Nuclear Security and Incident Response, U.S. Nuclear Regulatory Commission, Washington... 10 Energy 1 2014-01-01 2014-01-01 false Advance notification of shipment of category 1 quantities of radioactive material. 37.77 Section 37.77 Energy NUCLEAR REGULATORY COMMISSION PHYSICAL PROTECTION...

78 FR 16921 - Physical Protection of Byproduct Material

Federal Register 2010, 2011, 2012, 2013, 2014

2013-03-19

... 1 and category 2 thresholds are based on the quantities established by the International Atomic... orders that were issued to licensees using a graded approach based on the relative risk and quantity of... 5,400 Ytterbium-169 300 8,100 3 81.0 These materials and thresholds are based on the IAEA Code of...

Long-run evolution of the global economy: 1. Physical basis

NASA Astrophysics Data System (ADS)

Garrett, Timothy J.

2014-04-01

Climate change is a two-way street during the Anthropocene: civilization depends upon a favorable climate at the same time that it modifies it. Yet studies that forecast economic growth employ fundamentally different equations and assumptions than those used to model Earth's physical, chemical, and biological processes. In the interest of establishing a common theoretical framework, this article treats humanity like any other physical process; that is, as an open, nonequilibrium thermodynamic system that sustains existing circulations and furthers its material growth through the consumption and dissipation of energy. The link of physical to economic quantities comes from a prior result that establishes a fixed relationship between rates of global energy consumption and a historical accumulation of global economic wealth. What follows are nonequilibrium prognostic expressions for how wealth, energy consumption, and the Gross World Product (GWP) grow with time. This paper shows that the key components that determine whether civilization "innovates" itself toward faster economic growth include energy reserve discovery, improvements to human and infrastructure longevity, and reductions in the amount of energy required to extract raw materials. Growth slows due to a combination of prior growth, energy reserve depletion, and a "fraying" of civilization networks due to natural disasters. Theoretical and numerical arguments suggest that when growth rates approach zero, civilization becomes fragile to such externalities as natural disasters, and the risk is for an accelerating collapse.

Cascade-based attacks on complex networks

NASA Astrophysics Data System (ADS)

Motter, Adilson E.; Lai, Ying-Cheng

2002-12-01

We live in a modern world supported by large, complex networks. Examples range from financial markets to communication and transportation systems. In many realistic situations the flow of physical quantities in the network, as characterized by the loads on nodes, is important. We show that for such networks where loads can redistribute among the nodes, intentional attacks can lead to a cascade of overload failures, which can in turn cause the entire or a substantial part of the network to collapse. This is relevant for real-world networks that possess a highly heterogeneous distribution of loads, such as the Internet and power grids. We demonstrate that the heterogeneity of these networks makes them particularly vulnerable to attacks in that a large-scale cascade may be triggered by disabling a single key node. This brings obvious concerns on the security of such systems.

Mediating relationship of differential products in understanding integration in introductory physics

NASA Astrophysics Data System (ADS)

Amos, Nathaniel; Heckler, Andrew F.

2018-01-01

In the context of introductory physics, we study student conceptual understanding of differentials, differential products, and integrals and possible pathways to understanding these quantities. We developed a multiple choice conceptual assessment employing a variety of physical contexts probing physical understanding of these three quantities and administered the instrument to over 1000 students in first and second semester introductory physics courses. Using a regression-based mediation analysis with conceptual understanding of integration as the dependent variable, we found evidence consistent with a simple mediation model: the relationship between differentials scores and integral scores may be mediated by the understanding of differential products. The indirect effect (a quantifiable metric of mediation) was estimated as a b =0.29 , 95% CI [0.25, 0.33] for N =1102 Physics 1 students, and a b =0.27 , 95% CI [0.14, 0.48] for N =65 Physics 2 students. We also find evidence that the physical context of the questions can be an important factor. These results imply that for introductory physics courses, instructional emphasis first on differentials then on differential products in a variety of contexts may in turn promote better integral understanding.

Technologic Distractions (Part 1): Summary of Approaches to Manage Alert Quantity With Intent to Reduce Alert Fatigue and Suggestions for Alert Fatigue Metrics.

PubMed

Kane-Gill, Sandra L; O'Connor, Michael F; Rothschild, Jeffrey M; Selby, Nicholas M; McLean, Barbara; Bonafide, Christopher P; Cvach, Maria M; Hu, Xiao; Konkani, Avinash; Pelter, Michele M; Winters, Bradford D

2017-09-01

To provide ICU clinicians with evidence-based guidance on tested interventions that reduce or prevent alert fatigue within clinical decision support systems. Systematic review of PubMed, Embase, SCOPUS, and CINAHL for relevant literature from 1966 to February 2017. Focus on critically ill patients and included evaluations in other patient care settings, as well. Identified interventions designed to reduce or prevent alert fatigue within clinical decision support systems. Study selection was based on one primary key question to identify effective interventions that attempted to reduce alert fatigue and three secondary key questions that covered the negative effects of alert fatigue, potential unintended consequences of efforts to reduce alert fatigue, and ideal alert quantity. Data were abstracted by two reviewers independently using a standardized abstraction tool. Surveys, meeting abstracts, "gray" literature, studies not available in English, and studies with non-original data were excluded. For the primary key question, articles were excluded if they did not provide a comparator as key question 1 was designed as a problem, intervention, comparison, and outcome question. We anticipated that reduction in alert fatigue, including the concept of desensitization may not be directly measured and thus considered interventions that reduced alert quantity as a surrogate marker for alert fatigue. Twenty-six articles met the inclusion criteria. Approaches for managing alert fatigue in the ICU are provided as a result of reviewing tested interventions that reduced alert quantity with the anticipated effect of reducing fatigue. Suggested alert management strategies include prioritizing alerts, developing sophisticated alerts, customizing commercially available alerts, and including end user opinion in alert selection. Alert fatigue itself is studied less frequently, as an outcome, and there is a need for more precise evaluation. Standardized metrics for alert fatigue is needed to advance the field. Suggestions for standardized metrics are provided in this document.

Get Real!--Physically Reasonable Values for Teaching Electrostatics

ERIC Educational Resources Information Center

Morse, Robert A.

2016-01-01

Students get a sense of realistic values for physical situations from texts, but more importantly from solving problems. Therefore, problems should use realistic values for quantities to provide needed practice. Unfortunately, some problems on tests and in textbooks do not use realistic values. Physical situations in electrostatics seem to be…

Entanglement entropy and complexity for one-dimensional holographic superconductors

NASA Astrophysics Data System (ADS)

Kord Zangeneh, Mahdi; Ong, Yen Chin; Wang, Bin

2017-08-01

Holographic superconductor is an important arena for holography, as it allows concrete calculations to further understand the dictionary between bulk physics and boundary physics. An important quantity of recent interest is the holographic complexity. Conflicting claims had been made in the literature concerning the behavior of holographic complexity during phase transition. We clarify this issue by performing a numerical study on one-dimensional holographic superconductor. Our investigation shows that holographic complexity does not behave in the same way as holographic entanglement entropy. Nevertheless, the universal terms of both quantities are finite and reflect the phase transition at the same critical temperature.

Tachyonic quench in a free bosonic field theory

NASA Astrophysics Data System (ADS)

Montes, Sebastián; Sierra, Germán; Rodríguez-Laguna, Javier

2018-02-01

We present a characterization of a bosonic field theory driven by a free (Gaussian) tachyonic Hamiltonian. This regime is obtained from a theory describing two coupled bosonic fields after a regular quench. Relevant physical quantities such as simple correlators, entanglement entropies, and the mutual information of disconnected subregions are computed. We show that the causal structure resembles a critical (massless) quench. For short times, physical quantities also resemble critical quenches. However, exponential divergences end up dominating the dynamics in a very characteristic way. This is related to the fact that the low-frequency modes do not equilibrate. Some applications and extensions are outlined.

Quantity, Revisited: An Object-Oriented Reusable Class

NASA Technical Reports Server (NTRS)

Funston, Monica Gayle; Gerstle, Walter; Panthaki, Malcolm

1998-01-01

"Quantity", a prototype implementation of an object-oriented class, was developed for two reasons: to help engineers and scientists manipulate the many types of quantities encountered during routine analysis, and to create a reusable software component to for large domain-specific applications. From being used as a stand-alone application to being incorporated into an existing computational mechanics toolkit, "Quantity" appears to be a useful and powerful object. "Quantity" has been designed to maintain the full engineering meaning of values with respect to units and coordinate systems. A value is a scalar, vector, tensor, or matrix, each of which is composed of Value Components, each of which may be an integer, floating point number, fuzzy number, etc., and its associated physical unit. Operations such as coordinate transformation and arithmetic operations are handled by member functions of "Quantity". The prototype has successfully tested such characteristics as maintaining a numeric value, an associated unit, and an annotation. In this paper we further explore the design of "Quantity", with particular attention to coordinate systems.

Interactive Physics: the role of interactive learning objects in teaching Physics in Engineering

NASA Astrophysics Data System (ADS)

Benito, R. M.; Cámara, M. E.; Arranz, F. J.

2009-04-01

In this work we present the results of a Project in educational innovation entitled "Interactive Physics". We have developed resources for teaching Physics for students of Engineering, with an emphasis in conceptual reinforcement and addressing the shortcomings of students entering the University. The resources developed include hypertext, graphics, equations, quizzes and more elaborated problems that cover the customary syllabus in first-year Physics: kinematics and dynamics, Newton laws, electricity and magnetism, elementary circuits… The role of vector quantities is stressed and we also provide help for the most usual mathematical tools (calculus and trigonometric formulas). The structure and level of detail of the resources are fitted to the conceptual difficulties that most of the students find. Some of the most advanced resources we have developed are interactive simulations. These are real simulations of key physical situations, not only animations. They serve as learning objects, in the well known sense of small reusable digital objects that are self-contained and tagged with metadata. In this sense, we use them to link concepts and content through interaction with active engagement of the student. The development of an interactive simulation involves several steps. First, we identify common pitfalls in the conceptual framework of the students and the points in which they stumble frequently. Then we think of a way to make clear the physical concepts using a simulation. After that, we program the simulation (using Flash or Java) and finally the simulation is tested with the students, and we reelaborate some parts of it in terms of usability. In our communication, we discuss the usefulness of these interactive simulations in teaching Physics for engineers, and their integration in a more comprehensive b-learning system.

40 CFR 401.11 - General definitions.

Code of Federal Regulations, 2010 CFR

2010-07-01

..., incinerator residue, sewage, garbage, sewage sludge, munitions, chemical wastes, biological materials... the chemical, physical, biological and radiological integrity of water. (h) The term discharge of... restriction established by the Administrator on quantities, rates, and concentrations of chemical, physical...

Planning a School Physics Experiment.

ERIC Educational Resources Information Center

Blasiak, Wladyslaw

1986-01-01

Presents a model for planning the measurement of physical quantities. Provides two examples of optimizing the conditions of indirect measurement for laboratory experiments which involve measurements of acceleration due to gravity and of viscosity by means of Stokes' formula. (ML)

Histology and cell wall biochemistry of stone cells in the physical defence of conifers against insects.

PubMed

Whitehill, Justin G A; Henderson, Hannah; Schuetz, Mathias; Skyba, Oleksandr; Yuen, Macaire Man Saint; King, John; Samuels, A Lacey; Mansfield, Shawn D; Bohlmann, Jörg

2016-08-01

Conifers possess an array of physical and chemical defences against stem-boring insects. Stone cells provide a physical defence associated with resistance against bark beetles and weevils. In Sitka spruce (Picea sitchensis), abundance of stone cells in the cortex of apical shoots is positively correlated with resistance to white pine weevil (Pissodes strobi). We identified histological, biochemical and molecular differences in the stone cell phenotype of weevil resistant (R) or susceptible (S) Sitka spruce genotypes. R trees displayed significantly higher quantities of cortical stone cells near the apical shoot node, the primary site for weevil feeding. Lignin, cellulose, xylan and mannan were the most abundant components of stone cell secondary walls, respectively. Lignin composition of stone cells isolated from R trees contained a higher percentage of G-lignin compared with S trees. Transcript profiling revealed higher transcript abundance in the R genotype of coumarate 3-hydroxylase, a key monolignol biosynthetic gene. Developing stone cells in current year apical shoots incorporated fluorescent-tagged monolignol into the secondary cell wall, while mature stone cells of previous year apical shoots did not. Stone cell development is an ephemeral process, and fortification of shoot tips in R trees is an effective strategy against insect feeding. © 2015 John Wiley & Sons Ltd.

Assessing the Effects of Data Compression in Simulations Using Physically Motivated Metrics

DOE PAGES

Laney, Daniel; Langer, Steven; Weber, Christopher; ...

2014-01-01

This paper examines whether lossy compression can be used effectively in physics simulations as a possible strategy to combat the expected data-movement bottleneck in future high performance computing architectures. We show that, for the codes and simulations we tested, compression levels of 3–5X can be applied without causing significant changes to important physical quantities. Rather than applying signal processing error metrics, we utilize physics-based metrics appropriate for each code to assess the impact of compression. We evaluate three different simulation codes: a Lagrangian shock-hydrodynamics code, an Eulerian higher-order hydrodynamics turbulence modeling code, and an Eulerian coupled laser-plasma interaction code. Wemore » compress relevant quantities after each time-step to approximate the effects of tightly coupled compression and study the compression rates to estimate memory and disk-bandwidth reduction. We find that the error characteristics of compression algorithms must be carefully considered in the context of the underlying physics being modeled.« less

Courant number and unsteady flow computation

USGS Publications Warehouse

Lai, Chintu; ,

1993-01-01

The Courant number C, the key to unsteady flow computation, is a ratio of physical wave velocity, ??, to computational signal-transmission velocity, ??, i.e., C = ??/??. In this way, it uniquely relates a physical quantity to a mathematical quantity. Because most unsteady open-channel flows are describable by a set of n characteristic equations along n characteristic paths, each represented by velocity ??i, i = 1,2,....,n, there exist as many as n components for the numerator of C. To develop a numerical model, a numerical integration must be made on each characteristic curve from an earlier point to a later point on the curve. Different numerical methods are available in unsteady flow computation due to the different paths along which the numerical integration is actually performed. For the denominator of C, the ?? defined as ?? = ?? 0 = ??x/??t has been customarily used; thus, the Courant number has the familiar form of C?? = ??/??0. This form will be referred to as ???common Courant number??? in this paper. The commonly used numerical criteria C?? for stability, neutral stability and instability, are imprecise or not universal in the sense that r0 does not always reflect the true maximum computational data-transmission speed of the scheme at hand, i.e., Ctau is no indication for the Courant constraint. In view of this , a new Courant number, called the ???natural Courant number???, Cn, that truly reflects the Courant constraint, has been defined. However, considering the numerous advantages inherent in the traditional C??, a useful and meaningful composite Courant number, denoted by C??* has been formulated from C??. It is hoped that the new aspects of the Courant number discussed herein afford the hydraulician a broader perspective, consistent criteria, and unified guidelines, with which to model various unsteady flows.

Social Support in Women with Fibromyalgia: Is Quality More Important than Quantity?

ERIC Educational Resources Information Center

Franks, Heather M.; Cronan, Terry A.; Oliver, Karen

2004-01-01

The present study is an examination of the effects of quality and quantity of social support on the psychological and physical well-being of women with fibromyalgia syndrome (FMS). Participants were 568 women who were members of a health maintenance organization (HMO) with a confirmed diagnosis of FMS. Participants were administered a battery of…

Can One Take the Logarithm or the Sine of a Dimensioned Quantity or a Unit? Dimensional Analysis Involving Transcendental Functions

ERIC Educational Resources Information Center

Matta, Cherif F.; Massa, Lou; Gubskaya, Anna V.; Knoll, Eva

2011-01-01

The fate of dimensions of dimensioned quantities that are inserted into the argument of transcendental functions such as logarithms, exponentiation, trigonometric, and hyperbolic functions is discussed. Emphasis is placed on common misconceptions that are not often systematically examined in undergraduate courses of physical sciences. The argument…

A post-processor for the PEST code

DOE Office of Scientific and Technical Information (OSTI.GOV)

Priesche, S.; Manickam, J.; Johnson, J.L.

1992-01-01

A new post-processor has been developed for use with output from the PEST tokamak stability code. It allows us to use quantities calculated by PEST and take better advantage of the physical picture of the plasma instability which they can provide. This will improve comparison with experimentally measured quantities as well as facilitate understanding of theoretical studies.

A Physics Experiment Concerning the Measurement of the Torque of a Rotating Body Using a Magnetoelectrical Technique

ERIC Educational Resources Information Center

Sakon, Takuo; Nakagawa, Keisuke

2016-01-01

A physical experiment concerning the moment of inertia of a rigid disk is described. Basic physical quantities such as the moment of inertia and torque are very important in elementary physics courses. This experiment was designed to improve students' understanding of the relation between the rigid moment of inertia and torque. The moment of…

The Surface-to-Volume Ratio in Thermal Physics: From Cheese Cube Physics to Animal Metabolism

ERIC Educational Resources Information Center

Planinsic, Gorazd; Vollmer, Michael

2008-01-01

The surface-to-volume ratio is an important quantity in thermal physics. For example it governs the behaviour of heating or cooling of physical objects as a function of size like, e.g. cubes or spheres made of different material. The starting point in our paper is the simple physics problem of how cheese cubes of different sizes behave if heated…

Dimensional Analysis in Physics and the Buckingham Theorem

ERIC Educational Resources Information Center

Misic, Tatjana; Najdanovic-Lukic, Marina; Nesic, Ljubisa

2010-01-01

Dimensional analysis is a simple, clear and intuitive method for determining the functional dependence of physical quantities that are of importance to a certain process. However, in physics textbooks, very little space is usually given to this approach and it is often presented only as a diagnostic tool used to determine the validity of…

Focusing on Main Street's Problems from Secluded Laboratory Retreats

ERIC Educational Resources Information Center

Kushner, Lawrence M.

1973-01-01

A report on the National Bureau of Standards is presented. It provides national measurement standards for some 40 physical quantities related through the laws of physics to the basic six - length, time, mass, temperature, electric current, and luminous intensity. (DF)

Exploration of dynamic dipole polarizability of impurity doped quantum dots in presence of noise

NASA Astrophysics Data System (ADS)

Ghosh, Anuja; Bera, Aindrila; Saha, Surajit; Arif, Sk. Md.; Ghosh, Manas

2018-02-01

Present study strives to perform a rigorous exploration of dynamic dipole polarizability (DDP) of GaAs quantum dot (QD) containing dopant with special reference to influence of Gaussian white noise. Several physical quantities have been varied over a range to observe the modulations of the DDP profiles. Aforesaid physical quantities include magnetic field, confinement potential, dopant location, dopant potential, noise strength, aluminium concentration (only for Alx Ga1 - x As alloy QD), position-dependent effective mass (PDEM), position-dependent dielectric screening function (PDDSF), anisotropy, hydrostatic pressure (HP) and temperature. The DDP profiles reveal noticeable characteristics governed by the particular physical quantity involved, presence/absence of noise, the manner (additive/multiplicative) noise is applied to the system and the incoming photon frequency. As a general observation we have found that additive noise causing greater deviation of the DDP profile from noise-free state than its multiplicative neighbor. The study highlights viable means of harnessing DDP of doped QD under the governance of noise by appropriate adjustment of several relevant factors. The study merits importance in the light of technological applications of QD-based devices where noise appears as an integral component.

Linking ecosystems, food webs, and fish production: subsidies in salmonid watersheds

USGS Publications Warehouse

Wipfli, Mark S.; Baxter, Colden V.

2010-01-01

Physical characteristics of riverine habitats, such as large wood abundance, pool geometry and abundance, riparian vegetation cover, and surface flow conditions, have traditionally been thought to constrain fish production in these ecosystems. Conversely, the role of food resources (quantity and quality) in controlling fish production has received far less attention and consideration, though they can also be key productivity drivers. Traditional freshwater food web illustrations have typically conveyed the notion that most fish food is produced within the local aquatic habitat itself, but the concepts and model we synthesize in this article show that most fish food comes from external or very distant sources—including subsidies from marine systems borne from adult returns of anadromous fishes, from fishless headwater tributaries that transport prey to downstream fish, and from adjacent streamside vegetation and associated habitats. The model we propose further illustrates how key trophic pathways and food sources vary through time and space throughout watersheds. Insights into how food supplies affect fishes can help guide how we view riverine ecosystems, their structure and function, their interactions with marine and terrestrial systems, and how we manage natural resources, including fish, riparian habitats, and forests.

Poromechanical response of naturally fractured sorbing media

NASA Astrophysics Data System (ADS)

Kumar, Hemant

The injection of CO2 in coal seams has been utilized for enhanced gas recovery and potential CO2 sequestration in unmineable coal seams. It is advantageous because as it enhances the production and significant volumes of CO2 may be stored simultaneously. The key issues for enhanced gas recovery and geologic sequestration of CO2 include (1) Injectivity prediction: The chemical and physical processes initiated by the injection of CO2 in the coal seam leads to permeability/porosity changes (2) Up scaling: Development of full scale coupled reservoir model which may predict the enhanced production, associated permeability changes and quantity of sequestered CO2. (3) Reservoir Stimulation: The coalbeds are often fractured and proppants are placed into the fractures to prevent the permeability reduction but the permeability evolution in such cases is poorly understood. These issues are largely governed by dynamic coupling of adsorption, fluid exchange, transport, water content, stress regime, fracture geometry and physiomechanical changes in coals which are triggered by CO 2 injection. The understanding of complex interactions in coal has been investigated through laboratory experiments and full reservoir scale models are developed to answer key issues. (Abstract shortened by ProQuest.).

Identification of key factors affecting the water pollutant concentration in the sluice-controlled river reaches of the Shaying River in China via statistical analysis methods.

PubMed

Dou, Ming; Zhang, Yan; Zuo, Qiting; Mi, Qingbin

2015-08-01

The construction of sluices creates a strong disturbance in water environmental factors within a river. The change in water pollutant concentrations of sluice-controlled river reaches (SCRRs) is more complex than that of natural river segments. To determine the key factors affecting water pollutant concentration changes in SCRRs, river reaches near the Huaidian Sluice in the Shaying River of China were selected as a case study, and water quality monitoring experiments based on different regulating modes were implemented in 2009 and 2010. To identify the key factors affecting the change rates for the chemical oxygen demand of permanganate (CODMn) and ammonia nitrogen (NH3-N) concentrations in the SCRRs of the Huaidian Sluice, partial correlation analysis, principal component analysis and principal factor analysis were used. The results indicate four factors, i.e., the inflow quantity from upper reaches, opening size of sluice gates, water pollutant concentration from upper reaches, and turbidity before the sluice, which are the common key factors for the CODMn and NH3-N concentration change rates. Moreover, the dissolved oxygen before a sluice is a key factor for the permanganate concentration from CODMn change rate, and the water depth before a sluice is a key factor for the NH3-N concentration change rate. Multiple linear regressions between the water pollutant concentration change rate and key factors were established via multiple linear regression analyses, and the quantitative relationship between the CODMn and NH3-N concentration change rates and key affecting factors was analyzed. Finally, the mechanism of action for the key factors affecting the water pollutant concentration changes was analyzed. The results reveal that the inflow quantity from upper reaches, opening size of sluice gates, permanganate concentration from CODMn from upper reaches and dissolved oxygen before the sluice have a negative influence and the turbidity before the sluice has a positive influence on the permanganate concentration from CODMn change rates and that the opening size of sluice gates, NH3-N concentration from upper reaches, and water depth before the sluice have a negative influence and the inflow quantity from upper reaches and turbidity before the sluice have a positive influence on the NH3-N concentration change rates, which provides a scientific grounding for pollution control and sluice operations in SCRRs.

Economical and eco-friendly recycling of used dry batteries for synthesis of graphene oxide by sheer exfoliation in presence of SDS

NASA Astrophysics Data System (ADS)

Kochrekar, Sachin; Agharkar, Mahesh; Salgaonkar, Manjunath; Gharge, Mrunal; Hidouri, Slah; Azeez, Musibau A.

2015-06-01

Graphene is a two-dimensional form of graphite that has attracted great curiosity for its novel physical properties. A key challenge that has emerged is how to create large amounts of graphene at low cost. The purpose of this Paper is to explore a new method to exfoliate graphite extracted from used dry battery in a small scale blender; in presence of SDS surfactant to synthesize graphene oxide, which can be then reduced to graphene. Quantity of SDS required is extremely less (1/10th) of graphite, and it replaces several steps and chemicals such as KMnO4, H2O2, H2SO4 and NaNO3. In this paper, we present the new process and preliminary characterization of synthesized graphene oxide by Raman and UV-Vis absorbance spectroscopy and ATR-IR spectroscopy.

Standing Waves in an Elastic Spring: A Systematic Study by Video Analysis

ERIC Educational Resources Information Center

Rodrigues Ventura, Daniel; Simeão de Carvalho, Paulo; Adriano Dias, Marco

2017-01-01

The word "wave" is part of the daily language of every student. However, the physical understanding of the concept demands a high level of abstract thought. In physics, waves are oscillating variations of a physical quantity that involve the transfer of energy from one point to another, without displacement of matter. A wave can be…

The Scope & Sequence of Fitness Education for PreK-16 Programs: NASPE Fitness Education Project

ERIC Educational Resources Information Center

National Association for Sport and Physical Education, 2012

2012-01-01

In May 2006, the National Association for Sport and Physical Education (NASPE) received funding from the Centers for Disease Control and Prevention's (CDC) Division of Adolescent and School Health to improve the quality and quantity of physical education and physical activity programs across the United States. The cooperative agreement project…

A physically constrained classical description of the homogeneous nucleation of ice in water.

PubMed

Koop, Thomas; Murray, Benjamin J

2016-12-07

Liquid water can persist in a supercooled state to below 238 K in the Earth's atmosphere, a temperature range where homogeneous nucleation becomes increasingly probable. However, the rate of homogeneous ice nucleation in supercooled water is poorly constrained, in part, because supercooled water eludes experimental scrutiny in the region of the homogeneous nucleation regime where it can exist only fleetingly. Here we present a new parameterization of the rate of homogeneous ice nucleation based on classical nucleation theory. In our approach, we constrain the key terms in classical theory, i.e., the diffusion activation energy and the ice-liquid interfacial energy, with physically consistent parameterizations of the pertinent quantities. The diffusion activation energy is related to the translational self-diffusion coefficient of water for which we assess a range of descriptions and conclude that the most physically consistent fit is provided by a power law. The other key term is the interfacial energy between the ice embryo and supercooled water whose temperature dependence we constrain using the Turnbull correlation, which relates the interfacial energy to the difference in enthalpy between the solid and liquid phases. The only adjustable parameter in our model is the absolute value of the interfacial energy at one reference temperature. That value is determined by fitting this classical model to a selection of laboratory homogeneous ice nucleation data sets between 233.6 K and 238.5 K. On extrapolation to temperatures below 233 K, into a range not accessible to standard techniques, we predict that the homogeneous nucleation rate peaks between about 227 and 231 K at a maximum nucleation rate many orders of magnitude lower than previous parameterizations suggest. This extrapolation to temperatures below 233 K is consistent with the most recent measurement of the ice nucleation rate in micrometer-sized droplets at temperatures of 227-232 K on very short time scales using an X-ray laser technique. In summary, we present a new physically constrained parameterization for homogeneous ice nucleation which is consistent with the latest literature nucleation data and our physical understanding of the properties of supercooled water.

A novel model of photothermal diffusion (PTD) for polymer nano-composite semiconducting of thin circular plate

NASA Astrophysics Data System (ADS)

Lotfy, Kh.

2018-05-01

In this article, theoretical discussions for a novel mathematical-physical Photothermal diffusion (PTD) model in the generalized thermoelasticity theory with photothermal processes and chemical action are introduced. The mean idea of this model depends on the interaction between quasi-particles (plasma waves) that depends on the kind of the used materials, the mechanical forces acting on the surface, the generalized thermo and mass diffusion (due to coupling of temperature fields with thermal waves and chemical potential) and the elastic waves. The one dimensional Laplace transforms is used to obtain the exact solution for some physical and chemical quantities for a thin circular plate of a semiconducting polymer nanocomposite such as silicon (Si). New variables are deduced and discussed. The obtained results of the physical quantities are presented analytically and illustrated graphically with some important applications.

First-principles Theory of Magnetic Multipoles in Condensed Matter Systems

NASA Astrophysics Data System (ADS)

Suzuki, Michi-To; Ikeda, Hiroaki; Oppeneer, Peter M.

2018-04-01

The multipole concept, which characterizes the spacial distribution of scalar and vector objects by their angular dependence, has already become widely used in various areas of physics. In recent years it has become employed to systematically classify the anisotropic distribution of electrons and magnetization around atoms in solid state materials. This has been fuelled by the discovery of several physical phenomena that exhibit unusual higher rank multipole moments, beyond that of the conventional degrees of freedom as charge and magnetic dipole moment. Moreover, the higher rank electric/magnetic multipole moments have been suggested as promising order parameters in exotic hidden order phases. While the experimental investigations of such anomalous phases have provided encouraging observations of multipolar order, theoretical approaches have developed at a slower pace. In particular, a materials' specific theory has been missing. The multipole concept has furthermore been recognized as the key quantity which characterizes the resultant configuration of magnetic moments in a cluster of atomic moments. This cluster multipole moment has then been introduced as macroscopic order parameter for a noncollinear antiferromagnetic structure in crystals that can explain unusual physical phenomena whose appearance is determined by the magnetic point group symmetry. It is the purpose of this review to discuss the recent developments in the first-principles theory investigating multipolar degrees of freedom in condensed matter systems. These recent developments exemplify that ab initio electronic structure calculations can unveil detailed insight in the mechanism of physical phenomena caused by the unconventional, multipole degree of freedom.

Effects of nonindigenous invasive species on water quality and quantity

Treesearch

Frank H. McCormick; Glen C. Contreras; Sherri L. Johnson

2010-01-01

Physical and biological disruptions of aquatic systems caused by invasive species alter water quantity and water quality. Recent evidence suggests that water is a vector for the spread of Sudden Oak Death disease and Port-Orfordcedar root disease. Since the 1990s, the public has become increasingly aware of the presence of invasive species in the Nation’s waters. Media...

41 CFR 109-27.5007-1 - Procedures.

Code of Federal Regulations, 2010 CFR

2010-07-01

...-INVENTORY MANAGEMENT 27.50-Inventory Management Policies, Procedures, and Guidelines § 109-27.5007-1 Procedures. The following procedures shall be established for taking physical inventory of stocks subjected to quantity controls as well as those under financial control: (a) Completion of a physical inventory...

Entanglement of purification through holographic duality

NASA Astrophysics Data System (ADS)

Umemoto, Koji; Takayanagi, Tadashi

2018-06-01

The gauge/gravity correspondence discovered two decades ago has had a profound influence on how the basic laws in physics should be formulated. In spite of the predictive power of holographic approaches (for example, when they are applied to strongly coupled condensed-matter physics problems), the fundamental reasons behind their success remain unclear. Recently, the role of quantum entanglement has come to the fore. Here we explore a quantity that connects gravity and quantum information in the light of the gauge/gravity correspondence. This is given by the minimal cross-section of the entanglement wedge that connects two disjoint subsystems in a gravity dual. In particular, we focus on various inequalities that are satisfied by this quantity. They suggest that it is a holographic counterpart of the quantity called entanglement of purification, which measures a bipartite correlation in a given mixed state. We give a heuristic argument that supports this identification based on a tensor network interpretation of holography. This predicts that the entanglement of purification satisfies the strong superadditivity for holographic conformal field theories.

Structure of the Small Amplitude Motion on Transversely Sheared Mean Flows

NASA Technical Reports Server (NTRS)

Goldstein, Marvin E.; Afsar, Mohamed Z.; Leib, Stewart J.

2013-01-01

This paper considers the small amplitude unsteady motion of an inviscid non-heat conducting compressible fluid on a transversely sheared mean flow. It extends a previous result given in Goldstein (1978(b) and 1979(a)) which shows that the hydrodynamic component of the motion is determined by two arbitrary convected quantities in the absence of solid surfaces or other external sources. The result is important because it can be used to specify appropriate boundary conditions for unsteady surface interaction problems on transversely sheared mean flows in the same way that the vortical component of the Kovasznay (1953) decomposition is used to specify these conditions for surface interaction problems on uniform mean flows. But unlike the Kovasznay (1953) case the arbitrary convected quantities no longer bear a simple relation to the physical variables. One purpose of this paper is to derive a formula that relates these quantities to the (physically measurable) vorticity and pressure fluctuations in the flow.

Case Report: The Impact of a Resubmission Intervention on Level 1 Distance Learning Students

ERIC Educational Resources Information Center

Pinchbeck, Jessica; Heaney, Caroline

2017-01-01

Student retention and success are key performance indicators within higher education. One of the key opportunities to address both of these lies with the support offered to students who fail a module but are entitled to resubmit. This study investigates the value of implementing a resubmission intervention to improve the quantity and quality of…

Statistical Mechanics of Japanese Labor Markets

NASA Astrophysics Data System (ADS)

Chen, He

We introduce a probabilistic model to analyze job-matching processes of recent Japanese labor markets, in particular, for university graduates by means of statistical physics. To make a model of the market efficiently, we take into account several hypotheses. Namely, each company fixes the (business year independent) number of opening positions for newcomers. The ability of gathering newcomers depends on the result of job matching process in past business years. This fact means that the ability of the company is weakening if the company did not make their quota or the company gathered applicants too much over the quota. All university graduates who are looking for their jobs can access the public information about the ranking of companies. By assuming the above essential key points, we construct the local energy function of each company and describe the probability that an arbitrary company gets students at each business year by a Boltzmann-Gibbs distribution. We evaluate the relevant physical quantities such as the employment rate and Gini index. We discuss social inequalities in labor markets, and provide some ways to improve these situations, such as the informal job offer rate, the job-worker mismatch between students and companies. Graduate School of Information Science and Technology.

Theory of Aging, Rejuvenation, and the Nonequilibrium Steady State in Deformed Polymer Glasses

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chen, Kang

The nonlinear Langevin equation theory of segmental relaxation, elasticity, and mechanical response of polymer glasses is extended to describe the coupled effects of physical aging, mechanical rejuvenation, and thermal history. The key structural variable is the amplitude of density fluctuations, and segmental dynamics proceeds via stress-modified activated barrier hopping on a dynamic free-energy profile. Mechanically generated disorder rejuvenation is quantified by a dissipative work argument and increases the amplitude of density fluctuations, thereby speeding up relaxation beyond that induced by the landscape tilting mechanism. The theory makes testable predictions for the time evolution and nonequilibrium steady state of the alphamore » relaxation time, density fluctuation amplitude, elastic modulus, and other properties. Model calculations reveal a rich dependence of these quantities on preaging time, applied stress, and temperature that reflects the highly nonlinear competition between physical aging and mechanical disordering. Thermal history is erased in the long-time limit, although the nonequilibrium steady state is not the literal fully rejuvenated freshly quenched glass. The present work provides the conceptual foundation for a quantitative treatment of the nonlinear mechanical response of polymer glasses under a variety of deformation protocols.« less

MAGNETIC BRAIDING AND PARALLEL ELECTRIC FIELDS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wilmot-Smith, A. L.; Hornig, G.; Pontin, D. I.

2009-05-10

The braiding of the solar coronal magnetic field via photospheric motions-with subsequent relaxation and magnetic reconnection-is one of the most widely debated ideas of solar physics. We readdress the theory in light of developments in three-dimensional magnetic reconnection theory. It is known that the integrated parallel electric field along field lines is the key quantity determining the rate of reconnection, in contrast with the two-dimensional case where the electric field itself is the important quantity. We demonstrate that this difference becomes crucial for sufficiently complex magnetic field structures. A numerical method is used to relax a braided magnetic field towardmore » an ideal force-free equilibrium; the field is found to remain smooth throughout the relaxation, with only large-scale current structures. However, a highly filamentary integrated parallel current structure with extremely short length-scales is found in the field, with the associated gradients intensifying during the relaxation process. An analytical model is developed to show that, in a coronal situation, the length scales associated with the integrated parallel current structures will rapidly decrease with increasing complexity, or degree of braiding, of the magnetic field. Analysis shows the decrease in these length scales will, for any finite resistivity, eventually become inconsistent with the stability of the coronal field. Thus the inevitable consequence of the magnetic braiding process is a loss of equilibrium of the magnetic field, probably via magnetic reconnection events.« less

Physics of singularities in pressure-impulse theory

NASA Astrophysics Data System (ADS)

Krechetnikov, R.

2018-05-01

The classical solution in the pressure-impulse theory for the inviscid, incompressible, and zero-surface-tension water impact of a flat plate at zero dead-rise angle exhibits both singular-in-time initial fluid acceleration, ∂v /∂ t |t =0˜δ (t ) , and a near-plate-edge spatial singularity in the velocity distribution, v ˜r-1 /2 , where r is the distance from the plate edge. The latter velocity divergence also leads to the interface being stretched infinitely right after the impact, which is another nonphysical artifact. From the point of view of matched asymptotic analysis, this classical solution is a singular limit when three physical quantities achieve limiting values: sound speed c0→∞ , fluid kinematic viscosity ν →0 , and surface tension σ →0 . This leaves open a question on how to resolve these singularities mathematically by including the neglected physical effects—compressibility, viscosity, and surface tension—first one by one and then culminating in the local compressible viscous solution valid for t →0 and r →0 , demonstrating a nontrivial flow structure that changes with the degree of the bulk compressibility. In the course of this study, by starting with the general physically relevant formulation of compressible viscous flow, we clarify the parameter range(s) of validity of the key analytical solutions including classical ones (inviscid incompressible and compressible, etc.) and understand the solution structure, its intermediate asymptotics nature, characteristics influencing physical processes, and the role of potential and rotational flow components. In particular, it is pointed out that sufficiently close to the plate edge surface tension must be taken into account. Overall, the idea is to highlight the interesting physics behind the singularities in the pressure-impulse theory.

Explicit tracking of uncertainty increases the power of quantitative rule-of-thumb reasoning in cell biology.

PubMed

Johnston, Iain G; Rickett, Benjamin C; Jones, Nick S

2014-12-02

Back-of-the-envelope or rule-of-thumb calculations involving rough estimates of quantities play a central scientific role in developing intuition about the structure and behavior of physical systems, for example in so-called Fermi problems in the physical sciences. Such calculations can be used to powerfully and quantitatively reason about biological systems, particularly at the interface between physics and biology. However, substantial uncertainties are often associated with values in cell biology, and performing calculations without taking this uncertainty into account may limit the extent to which results can be interpreted for a given problem. We present a means to facilitate such calculations where uncertainties are explicitly tracked through the line of reasoning, and introduce a probabilistic calculator called CALADIS, a free web tool, designed to perform this tracking. This approach allows users to perform more statistically robust calculations in cell biology despite having uncertain values, and to identify which quantities need to be measured more precisely to make confident statements, facilitating efficient experimental design. We illustrate the use of our tool for tracking uncertainty in several example biological calculations, showing that the results yield powerful and interpretable statistics on the quantities of interest. We also demonstrate that the outcomes of calculations may differ from point estimates when uncertainty is accurately tracked. An integral link between CALADIS and the BioNumbers repository of biological quantities further facilitates the straightforward location, selection, and use of a wealth of experimental data in cell biological calculations. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

Coupled Model Development between Groundwater Recharge Quantity and Climate Change in Nakdong River Watershed using GIS

NASA Astrophysics Data System (ADS)

Lee, M.; Jeongho, L.; Changsub, S.; SeongWoo, J.

2011-12-01

: Global climate change is disturbing the water circulation balance by changing rates of precipitation, recharge and discharge, and evapotranspiration. Groundwater, which occupies a considerable portion of the world's water resources, is related to climate change via surface water such as rivers, lakes, and marshes. In this study, the authors selected a relevant climate change scenario, A1B from the Special Report on Emission Scenario (SRES) which is distributed at Korea Meteorological Administration. By using data on temperature, rainfall, soil, and land use, the groundwater recharge rate for the research area was estimated by periodically and embodied as geographic information system (GIS). In order to calculate the groundwater recharge quantity, Visual HELP3 was used as main model, and the physical properties of weather, temperature, and soil layers were used as main input data. General changes to water circulation due to climate change have already been predicted. In order to systematically solve problems of ground circulation system, it may be urgent to recalculate the groundwater recharge quantity and consequent change under future climate change. The space-time calculation of changes of the groundwater recharge quantity in the study area may serve as a foundation to present additional measures to improve domestic groundwater resource management. Results showed that 26.19% of total precipitation was recharged from 1971 to 2000, 27.37% will be recharged from 2001 to 2030, 27.43% will be recharged from 2031 to 2050, and 26.06% will be recharged from 2051 to 2070, 27.88% will be recharged from 2051 to 2100. The groundwater recharge rate in this research showed susceptibility to changes in precipitation. The recharge rate was relatively little affected by the changes in Curve Number (CN), but it was rapidly reduced, as it approached the impermeable layers. Accordingly, the findings herein provide a basis for establishment of national plans on water resources management, use of groundwater in local areas for the purpose of settlement, and estimation of groundwater recharge quantities in areas where the groundwater hydrology is not measured. KEY WORDS: Groundwater recharge; Climate change; Curve Number; Special Report on Emissions Scenarios; Intergovernmental Panel on Climate Change

TOPICAL REVIEW Recent developments in inorganically filled carbon nanotubes: successes and challenges

NASA Astrophysics Data System (ADS)

Gautam, Ujjal K.; Costa, Pedro M. F. J.; Bando, Yoshio; Fang, Xiaosheng; Li, Liang; Imura, Masataka; Golberg, Dmitri

2010-10-01

Carbon nanotubes (CNTs) are a unique class of nanomaterials that can be imagined as rolled graphene sheets. The inner hollow of a CNT provides an extremely small, one-dimensional space for storage of materials. In the last decade, enormous effort has been spent to produce filled CNTs that combine the properties of both the host CNT and the guest filling material. CNTs filled with various inorganic materials such as metals, alloys, semiconductors and insulators have been obtained using different synthesis approaches including capillary filling and chemical vapor deposition. Recently, several potential applications have emerged for these materials, such as the measurement of temperature at the nanoscale, nano-spot welding, and the storage and delivery of extremely small quantities of materials. A clear distinction between this class of materials and other nanostructures is the existence of an enormous interfacial area between the CNT and the filling matter. Theoretical investigations have shown that the lattice mismatch and strong exchange interaction of CNTs with the guest material across the interface should result in reordering of the guest crystal structure and passivation of the surface dangling bonds and thus yielding new and interesting physical properties. Despite preliminary successes, there remain many challenges in realizing applications of CNTs filled with inorganic materials, such as a comprehensive understanding of their growth and physical properties and control of their structural parameters. In this article, we overview research on filled CNT nanomaterials with special emphasis on recent progress and key achievements. We also discuss the future scope and the key challenges emerging out of a decade of intensive research on these fascinating materials.

Utilization of turkey manure as granular activated carbon: physical, chemical and adsorptive properties.

PubMed

Lima, Isabel; Marshall, Wayne E

2005-01-01

The high availability of large quantities of turkey manure generated from turkey production makes it an attractive feedstock for carbon production. Pelletized samples of turkey litter and cake were converted to granular activated carbons (GACs) by steam activation. Water flow rate and activation time were changed to produce a range of activation conditions. The GACs were characterized for select physical (yield, surface area, bulk density, attrition), chemical (pH, surface charge) and adsorptive properties (copper ion uptake). Carbon physical and adsorptive properties were dependent on activation time and quantity of steam used as activant. Yields varied from 23% to 37%, surface area varied from 248 to 472 m(2)/g and copper ion adsorption varied from 0.72 to 1.86 mmol Cu(2+)/g carbon. Copper ion adsorption greatly exceeded the values for two commercial GACs. GACs from turkey litter and cake show considerable potential to remove metal ions from water.

Streetscape greenery and health: stress, social cohesion and physical activity as mediators.

PubMed

de Vries, Sjerp; van Dillen, Sonja M E; Groenewegen, Peter P; Spreeuwenberg, Peter

2013-10-01

Several studies have shown a positive relationship between local greenspace availability and residents' health, which may offer opportunities for health improvement. This study focuses on three mechanisms through which greenery might exert its positive effect on health: stress reduction, stimulating physical activity and facilitating social cohesion. Knowledge on mechanisms helps to identify which type of greenspace is most effective in generating health benefits. In eighty neighbourhoods in four Dutch cities data on quantity and quality of streetscape greenery were collected by observations. Data on self-reported health and proposed mediators were obtained for adults by mail questionnaires (N = 1641). Multilevel regression analyses, controlling for socio-demographic characteristics, revealed that both quantity and quality of streetscape greenery were related to perceived general health, acute health-related complaints, and mental health. Relationships were generally stronger for quality than for quantity. Stress and social cohesion were the strongest mediators. Total physical activity was not a mediator. Physical activity that could be undertaken in the public space (green activity) was, but less so than stress and social cohesion. With all three mediators included in the analysis, complete mediation could statistically be proven in five out of six cases. In these analyses the contribution of green activity was often not significant. The possibility that the effect of green activity is mediated by stress and social cohesion, rather than that it has a direct health effect, is discussed. Copyright © 2013 Elsevier Ltd. All rights reserved.

Would more social partners leads to enhanced health? The paradox between quantity and quality.

PubMed

Xing, Cai; Zhang, Xin; Cheng, Sheung-Tak

2017-09-01

In the current investigation, we examined the association between social network composition (SNC) and mental health, as well as whether quantity and quality of social network could influence mental health differently. The social network quantity and quality of 345 middle-aged and older Chinese adults were measured by the Social Convoy Questionnaire. The Chinese version of the Medical Outcome Studies 36-item Short-Form Health Survey (SF-36) was used to assess mental health while controlling for physical health. It was found that both quantity and quality of social network were associated with mental health, and more specifically that (1) quantity of peripheral partners (PP) was positively associated with mental health; (2) quality of emotionally close social partners (ECSP) influenced mental health the most; and (3) paradoxically, the effect of ECSP quality on mental health depended on quantity of ECSP, that is, participants with more ECSP showed a stronger association between ECSP quality and mental health. The findings replicated and extended previous studies on SNC and suggested that structure/quantity and quality of SNC were both important for mental health. © 2017 The Institute of Psychology, Chinese Academy of Sciences and John Wiley & Sons Australia, Ltd.

Crocodile Physics. [CD-ROM].

ERIC Educational Resources Information Center

1999

This high school physics resource is a simulator for optics, electronics, force, motion, and sound. Students can study oscillations, look at sound waves, and use probes to graph a wide variety of quantities. Over 100 activities are pre-written, and students can easily create their own additional activities using the multimedia editor. (WRM)

10 CFR 37.81 - Reporting of events.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 10 Energy 1 2014-01-01 2014-01-01 false Reporting of events. 37.81 Section 37.81 Energy NUCLEAR REGULATORY COMMISSION PHYSICAL PROTECTION OF CATEGORY 1 AND CATEGORY 2 QUANTITIES OF RADIOACTIVE MATERIAL Physical Protection in Transit § 37.81 Reporting of events. (a) The shipping licensee shall notify the...

When and Why Are the Values of Physical Quantities Expressed with Uncertainties? A Case Study of a Physics Undergraduate Laboratory Course

ERIC Educational Resources Information Center

Caussarieu, Aude; Tiberghien, Andrée

2017-01-01

The understanding of measurement is related to the understanding of the nature of science--one of the main goals of current international science teaching at all levels of education. This case study explores how a first-year university physics course deals with measurement uncertainties in the light of an epistemological analysis of measurement.…

The distinction between key ideas in teaching school physics and key ideas in the discipline of physics

NASA Astrophysics Data System (ADS)

Deng, Zongyi

2001-05-01

The distinction between key ideas in teaching a high school science and key ideas in the corresponding discipline of science has been largely ignored in scholarly discourse about what science teachers should teach and about what they should know. This article clarifies this distinction through exploring how and why key ideas in teaching high school physics differ from key ideas in the discipline of physics. Its theoretical underpinnings include Dewey's (1902/1990) distinction between the psychological and the logical and Harré's (1986) epistemology of science. It analyzes how and why the key ideas in teaching color, the speed of light, and light interference at the high school level differ from the key ideas at the disciplinary level. The thesis is that key ideas in teaching high school physics can differ from key ideas in the discipline in some significant ways, and that the differences manifest Dewey's distinction. As a result, the article challenges the assumption of equating key ideas in teaching a high school science with key ideas in the corresponding discipline of science, and the assumption that having a college degree in science is sufficient to teach high school science. Furthermore, the article expands the concept of pedagogical content knowledge by arguing that key ideas in teaching high school physics constitute an essential component.

Feedbacks Between Soil Structure and Microbial Activities in Soil

NASA Astrophysics Data System (ADS)

Bailey, V. L.; Smith, A. P.; Fansler, S.; Varga, T.; Kemner, K. M.; McCue, L. A.

2017-12-01

Soil structure provides the physical framework for soil microbial habitats. The connectivity and size distribution of soil pores controls the microbial access to nutrient resources for growth and metabolism. Thus, a crucial component of soil research is how a soil's three-dimensional structure and organization influences its biological potential on a multitude of spatial and temporal scales. In an effort to understand microbial processes at scale more consistent with a microbial community, we have used soil aggregates as discrete units of soil microbial habitats. Our research has shown that mean pore diameter (x-ray computed tomography) of soil aggregates varies with the aggregate diameter itself. Analyzing both the bacterial composition (16S) and enzyme activities of individual aggregates showed significant differences in the relative abundances of key members the microbial communities associated with high enzyme activities compared to those with low activities, even though we observed no differences in the size of the biomass, nor in the overall richness or diversity of these communities. We hypothesize that resources and substrates have stimulated key populations in the aggregates identified as highly active, and as such, we conducted further research that explored how such key populations (i.e. fungal or bacterial dominated populations) alter pathways of C accumulation in aggregate size domains and microbial C utilization. Fungi support and stabilize soil structure through both physical and chemical effects of their hyphal networks. In contrast, bacterial-dominated communities are purported to facilitate micro- and fine aggregate stabilization. Here we quantify the direct effects fungal versus bacterial dominated communities on aggregate formation (both the rate of aggregation and the quality, quantity and distribution of SOC contained within aggregates). A quantitative understanding of the different mechanisms through which fungi or bacteria shape aggregate formation could alter how we currently treat our predictions of soil biogeochemistry. Current predictions are largely site- or biome-specific; quantitative mechanisms could underpin "rules" that operate at the pore-scale leading to more robust, mechanistic models.

[Dosimetric system for assessing doses received by people occupationally exposed to external sources of ionizing radiation].

PubMed

Brodecki, Marcin; Domienik, Joanna U; Zmyślony, Marek

2012-01-01

The current system of dosimetric quantities has been defined by the International Commission on Radiological Protection (ICRP) and the International Commission on Radiation Units and Measurements (ICRU). Complexity of the system implies the physical nature of ionizing radiation, resulting from the presence of different types of radiation of different ionization capabilities, as well as the individual radiation sensitivity of biological material exposed. According to the latest recommendations, there are three types of dosimeter quantities relevant to radiation protection and radiological assessment of occupational exposure. These are the basic quantities, safety quantities and operational quantities. Dose limits for occupational exposure relate directly to the protection quantities, i.e. the equivalent dose and effective dose, while these quantities are practically unmeasurable in real measurement conditions. For this reason, in the system of dosimetric quantities directly measurable operating volumes were defined. They represent equivalents of the protection quantities that allow for a reliable assessment of equivalent and effective dose by conducting routine monitoring of occupational exposure. This paper presents the characteristics of these quantities, their relationships and importance in assessing individual effects of radiation. Also the methods for their implementation in personal and environmental dosimetry were showcased. The material contained in the article is a compendium of essential information about dosimetric quantities with reference to the contemporary requirements of the law, including the changed annual occupational exposure limit for the lens of the eye. The material is especially addressed to those responsible for dosimetry monitoring in the workplace, radiation protection inspectors and occupational health physicians.

Current databases on biological variation: pros, cons and progress.

PubMed

Ricós, C; Alvarez, V; Cava, F; García-Lario, J V; Hernández, A; Jiménez, C V; Minchinela, J; Perich, C; Simón, M

1999-11-01

A database with reliable information to derive definitive analytical quality specifications for a large number of clinical laboratory tests was prepared in this work. This was achieved by comparing and correlating descriptive data and relevant observations with the biological variation information, an approach that had not been used in the previous efforts of this type. The material compiled in the database was obtained from published articles referenced in BIOS, CURRENT CONTENTS, EMBASE and MEDLINE using "biological variation & laboratory medicine" as key words, as well as books and doctoral theses provided by their authors. The database covers 316 quantities and reviews 191 articles, fewer than 10 of which had to be rejected. The within- and between-subject coefficients of variation and the subsequent desirable quality specifications for precision, bias and total error for all the quantities accepted are presented. Sex-related stratification of results was justified for only four quantities and, in these cases, quality specifications were derived from the group with lower within-subject variation. For certain quantities, biological variation in pathological states was higher than in the healthy state. In these cases, quality specifications were derived only from the healthy population (most stringent). Several quantities (particularly hormones) have been treated in very few articles and the results found are highly discrepant. Therefore, professionals in laboratory medicine should be strongly encouraged to study the quantities for which results are discrepant, the 90 quantities described in only one paper and the numerous quantities that have not been the subject of study.

Global Water Cycle Agreement in the Climate Models Assessed in the IPCC AR4

NASA Technical Reports Server (NTRS)

Waliser, D.; Seo, K. -W.; Schubert, S.; Njoku, E.

2007-01-01

This study examines the fidelity of the global water cycle in the climate model simulations assessed in the IPCC Fourth Assessment Report. The results demonstrate good model agreement in quantities that have had a robust global observational basis and that are physically unambiguous. The worst agreement occurs for quantities that have both poor observational constraints and whose model representations can be physically ambiguous. In addition, components involving water vapor (frozen water) typically exhibit the best (worst) agreement, and fluxes typically exhibit better agreement than reservoirs. These results are discussed in relation to the importance of obtaining accurate model representation of the water cycle and its role in climate change. Recommendations are also given for facilitating the needed model improvements.

The invariance of classical electromagnetism under Charge-conjugation, Parity and Time-reversal (CPT) transformations

NASA Technical Reports Server (NTRS)

Norbury, John W.

1989-01-01

The invariance of classical electromagnetism under charge-conjugation, parity, and time-reversal (CPT) is studied by considering the motion of a charged particle in electric and magnetic fields. Upon applying CPT transformations to various physical quantities and noting that the motion still behaves physically demonstrates invariance.

Introducing Scale Analysis by Way of a Pendulum

ERIC Educational Resources Information Center

Lira, Ignacio

2007-01-01

Empirical correlations are a practical means of providing approximate answers to problems in physics whose exact solution is otherwise difficult to obtain. The correlations relate quantities that are deemed to be important in the physical situation to which they apply, and can be derived from experimental data by means of dimensional and/or scale…

10 CFR 150.14 - Commission regulatory authority for physical protection.

Code of Federal Regulations, 2012 CFR

2012-01-01

... significance in quantities greater than 15 grams of plutonium or uranium-233 or uranium-235 (enriched to 20 percent or more in the U-235 isotope) or any combination greater than 15 grams when computed by the equation grams=grams uranium-235+grams plutonium+grams uranium-233 shall meet the physical protection...

10 CFR 150.14 - Commission regulatory authority for physical protection.

Code of Federal Regulations, 2010 CFR

2010-01-01

... significance in quantities greater than 15 grams of plutonium or uranium-233 or uranium-235 (enriched to 20 percent or more in the U-235 isotope) or any combination greater than 15 grams when computed by the equation grams=grams uranium-235+grams plutonium+grams uranium-233 shall meet the physical protection...

10 CFR 150.14 - Commission regulatory authority for physical protection.

Code of Federal Regulations, 2011 CFR

2011-01-01

... significance in quantities greater than 15 grams of plutonium or uranium-233 or uranium-235 (enriched to 20 percent or more in the U-235 isotope) or any combination greater than 15 grams when computed by the equation grams=grams uranium-235+grams plutonium+grams uranium-233 shall meet the physical protection...

10 CFR 150.14 - Commission regulatory authority for physical protection.

Code of Federal Regulations, 2013 CFR

2013-01-01

... significance in quantities greater than 15 grams of plutonium or uranium-233 or uranium-235 (enriched to 20 percent or more in the U-235 isotope) or any combination greater than 15 grams when computed by the equation grams=grams uranium-235+grams plutonium+grams uranium-233 shall meet the physical protection...

10 CFR 150.14 - Commission regulatory authority for physical protection.

Code of Federal Regulations, 2014 CFR

2014-01-01

... significance in quantities greater than 15 grams of plutonium or uranium-233 or uranium-235 (enriched to 20 percent or more in the U-235 isotope) or any combination greater than 15 grams when computed by the equation grams=grams uranium-235+grams plutonium+grams uranium-233 shall meet the physical protection...

Enhancing Physical Education with Exergames and Wearable Technology

ERIC Educational Resources Information Center

Lindberg, Renny; Seo, Jungryul; Laine, Teemu H.

2016-01-01

Increases in the numbers of obese and overweight children are a major issue in post-industrial societies because obesity can lead to severe health-related problems. In addition, many challenges affect the quantity and quality of physical education (PE) provided by schools. Exergames that combine exercise with gaming have been recognized as a…

How Do We Present the Concept of Energy in Physics?

ERIC Educational Resources Information Center

Pujol, O.; Perez, J. P.

2007-01-01

Scientific and pedagogical comments about the fundamental physical concept of energy are made. In particular, we argue for an historical presentation of this concept because its essential justification is the research, conscious or not, of a characteristic quantity of a system whose fundamental property is to be conservative. Some delicate issues…

76 FR 8871 - Walnuts Grown in California; Decreased Assessment Rate

Federal Register 2010, 2011, 2012, 2013, 2014

2011-02-16

... than the rate previously in effect. The quantity of assessable walnuts for the 2010-11 marketing year... contains regulatory documents #0;having general applicability and legal effect, most of which are keyed #0... 8871

Physical Limits on the Predictability of Erosion and Sediment Transport by Landslides and Debris Flows

NASA Astrophysics Data System (ADS)

Iverson, R. M.

2015-12-01

Episodic landslides and debris flows play a key role in sculpting many steep landscapes, and they also pose significant natural hazards. Field evidence, laboratory experiments, and theoretical analyses show that variations in the quantity, speed, and distance of sediment transport by landslides and debris flows can depend strongly on nuanced differences in initial conditions. Moreover, initial conditions themselves can be strongly dependent on the geological legacy of prior events. The scope of these dependencies is revealed by the results of landslide dynamics experiments [Iverson et al., Science, 2000], debris-flow erosion experiments [Iverson et al., Nature Geosci., 2011], and numerical simulations of the highly destructive 2014 Oso, Washington, landslide [Iverson et al., Earth Planet. Sci. Let., 2015]. In each of these cases, feedbacks between basal sediment deformation and pore-pressure generation cause the speed and distance of sediment transport to be very sensitive to subtle differences in the ambient sediment porosity and water content. On the other hand, the onset of most landslides and debris flows depends largely on pore-water pressure distributions and only indirectly on sediment porosity and water content. Thus, even if perfect predictions of the locations and timing of landslides and debris flows were available, the dynamics of the events - and their consequent hazards and sediment transport - would be difficult to predict. This difficulty is a manifestation of the nonlinear physics involved, rather than of poor understanding of those physics. Consequently, physically based models for assessing the hazards and sediment transport due to landslides and debris flows must take into account both evolving nonlinear dynamics and inherent uncertainties about initial conditions. By contrast, landscape evolution models that use prescribed algebraic formulas to represent sediment transport by landslides and debris flows lack a sound physical basis.

The notion of snow grain shape: Ambiguous definitions, retrievalfrom tomography and implications on remote sensing

NASA Astrophysics Data System (ADS)

Krol, Q. E.; Loewe, H.

2016-12-01

Grain shape is known to influence the effective physical properties of snow and therefore included in the international classification of seasonal snow. Accordingly, snowpack models account for phenomenological shape parameters (sphericity, dendricity) to capture shape variations. These parameters are however difficult to validate due to the lack of clear-cut definitions from the 3D microstucture and insufficient links to physical properties. While the definition of traditional shape was tailored to the requirements of observers, a more objective definition should be tailored to the requirements of physical properties, by analyzing geometrical (shape) corrections in existing theoretical formulations directly. To this end we revisited the autocorrelation function (ACF) and the chord length distribution (CLD) of snow. Both functions capture size distributions of the microstructure, can be calculated from X-ray tomography and are related to various physical properties. Both functions involve the optical equivalent diameter as dominant quantity, however the respective higher-order geometrical correction differ. We have analyzed these corrections, namely interfacial curvatures for the ACF and the second moment for the CLD, using an existing data set of 165 tomography samples. To unify the notion of shape, we derived various statistical relations between the length scales. Our analysis bears three key practical implications. First, we derived a significantly improved relation between the exponential correlation length and the optical diameter by taking curvatures into account. This adds to the understanding of linking "microwave grain size" and "optical grain size" of snow for remote sensing. Second, we retrieve the optical shape parameter (commonly referred to as B) from tomography images via the moment of the CLD. Third, shape variations seen by observers do not necessarily correspond to shape variations probed by physical properties.

Rainfall and runoff quantity and quality data collected at four urban land-use catchments in Fresno, California, October 1981-April 1983

USGS Publications Warehouse

Oltmann, R.N.; Guay, J.R.; Shay, J.M.

1987-01-01

Data were collected as part of the National Urban Runoff Program to characterize urban runoff in Fresno, California. Rainfall-runoff quantity and quality data are included along with atmospheric dry-deposition and street-surface particulate quality data. The data are presented in figures and tables that reflect four land uses: industrial, single-dwelling residential, multiple-dwelling residential, and commercial. A total of 255 storms were monitored for rainfall and runoff quantity. Runoff samples from 112 of these storms were analyzed for physical, organic, inorganic, and biological constituents. The majority of the remaining storms have pH and specific conductance data only. Ninety-two composite rain samples were collected. Of these, 63 were analyzed for physical, inorganic, and (or) organic constituents. The remaining rainfall samples have pH and specific conductance data only. Nineteen atmospheric deposition and 21 street-particulate samples were collected and analyzed for inorganic and organic constituents. The report also details equipment utilization and operation, and discusses data collection methods. (USGS)

Unified Bohm criterion

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kos, L.; Tskhakaya, D. D.; Jelić, N.

2015-09-15

Recent decades have seen research into the conditions necessary for the formation of the monotonic potential shape in the sheath, appearing at the plasma boundaries like walls, in fluid, and kinetic approximations separately. Although either of these approaches yields a formulation commonly known as the much-acclaimed Bohm criterion (BC), the respective results involve essentially different physical quantities that describe the ion gas behavior. In the fluid approach, such a quantity is clearly identified as the ion directional velocity. In the kinetic approach, the ion behavior is formulated via a quantity (the squared inverse velocity averaged by the ion distribution function)more » without any clear physical significance, which is, moreover, impractical. In the present paper, we try to explain this difference by deriving a condition called here the Unified Bohm Criterion, which combines an advanced fluid model with an upgraded explicit kinetic formula in a new form of the BC. By introducing a generalized polytropic coefficient function, the unified BC can be interpreted in a form that holds, irrespective of whether the ions are described kinetically or in the fluid approximation.« less

Image model: new perspective for image processing and computer vision

NASA Astrophysics Data System (ADS)

Ziou, Djemel; Allili, Madjid

2004-05-01

We propose a new image model in which the image support and image quantities are modeled using algebraic topology concepts. The image support is viewed as a collection of chains encoding combination of pixels grouped by dimension and linking different dimensions with the boundary operators. Image quantities are encoded using the notion of cochain which associates values for pixels of given dimension that can be scalar, vector, or tensor depending on the problem that is considered. This allows obtaining algebraic equations directly from the physical laws. The coboundary and codual operators, which are generic operations on cochains allow to formulate the classical differential operators as applied for field functions and differential forms in both global and local forms. This image model makes the association between the image support and the image quantities explicit which results in several advantages: it allows the derivation of efficient algorithms that operate in any dimension and the unification of mathematics and physics to solve classical problems in image processing and computer vision. We show the effectiveness of this model by considering the isotropic diffusion.

Impact of Hydrogeological Uncertainty on Estimation of Environmental Risks Posed by Hydrocarbon Transportation Networks

NASA Astrophysics Data System (ADS)

Ciriello, V.; Lauriola, I.; Bonvicini, S.; Cozzani, V.; Di Federico, V.; Tartakovsky, Daniel M.

2017-11-01

Ubiquitous hydrogeological uncertainty undermines the veracity of quantitative predictions of soil and groundwater contamination due to accidental hydrocarbon spills from onshore pipelines. Such predictions, therefore, must be accompanied by quantification of predictive uncertainty, especially when they are used for environmental risk assessment. We quantify the impact of parametric uncertainty on quantitative forecasting of temporal evolution of two key risk indices, volumes of unsaturated and saturated soil contaminated by a surface spill of light nonaqueous-phase liquids. This is accomplished by treating the relevant uncertain parameters as random variables and deploying two alternative probabilistic models to estimate their effect on predictive uncertainty. A physics-based model is solved with a stochastic collocation method and is supplemented by a global sensitivity analysis. A second model represents the quantities of interest as polynomials of random inputs and has a virtually negligible computational cost, which enables one to explore any number of risk-related contamination scenarios. For a typical oil-spill scenario, our method can be used to identify key flow and transport parameters affecting the risk indices, to elucidate texture-dependent behavior of different soils, and to evaluate, with a degree of confidence specified by the decision-maker, the extent of contamination and the correspondent remediation costs.

Time-Chunking and Hyper-Refocusing in a Digitally-Enabled Workplace: Six Forms of Knowledge Workers

PubMed Central

Gaskin, James E.; Skousen, Tanner

2016-01-01

Until the turn of the millennium, switching tasks required moving locations or reconfiguring physical workspaces. However, contemporary digital tools and workspaces allow knowledge workers to perform an increasingly diverse set of tasks, with an increasingly extending arm of influence, all from the same physical location without any physical reconfigurations or traversing of physical space. Along with this increased ambidexterity comes an increase in the quantity and frequency of demands on the time of knowledge workers. This digitalization of work now tethers their ability to perform largely to their ability to intensely focus in small chunks, and then “hyper-jump” that focus to another task without traversing the cognitive cool downs or warm ups required to reconfigure their train of thought from one task to another. Accordingly, they must become more like the hyper-functioning tools they employ if they are to avoid becoming the bottleneck resource in the configuration of socio-technical elements comprising their work routines. In order to better understand how knowledge workers manage their time and maintain focus across multiple and interrupting tasks, we leverage current time prioritization literature to propose and theorize around two key constructs: time-chunking and hyper-refocusing. By combining the possible values for these two constructs, we hypothesize the emergence of six forms of knowledge workers and their relative expected performance. The effects of digitalization on these new worker forms are discussed. We conclude by discussing opportunities for new research questions regarding time-chunking strategies and the hyper-refocusing ability. PMID:27822193

Coherence, quantum Fisher information, superradiance, and entanglement as interconvertible resources

NASA Astrophysics Data System (ADS)

Tan, Kok Chuan; Choi, Seongjeon; Kwon, Hyukjoon; Jeong, Hyunseok

2018-05-01

We demonstrate that quantum Fisher information and superradiance can be formulated as coherence measures in accordance with the resource theory of coherence, thus establishing a direct link between metrological resources, superradiance, and coherence. The arguments are generalized to show that coherence may be considered as the underlying fundamental resource for any functional of state that is first of all faithful, and second, concave or linear. It is also shown that quantum Fisher information and the superradiant quantity are in fact antithetical resources in the sense that if coherence were directed to saturate one quantity, then it must come at the expense of the other. Finally, a key result of the paper is to demonstrate that coherence, quantum Fisher information, superradiant quantity, and entanglement are mutually interconvertible resources under incoherent operations.

Measurement system

NASA Technical Reports Server (NTRS)

Turner, J. W. (Inventor)

1973-01-01

A measurement system is described for providing an indication of a varying physical quantity represented by or converted to a variable frequency signal. Timing pulses are obtained marking the duration of a fixed number, or set, of cycles of the sampled signal and these timing pulses are employed to control the period of counting of cycles of a higher fixed and known frequency source. The counts of cycles obtained from the fixed frequency source provide a precise measurement of the average frequency of each set of cycles sampled, and thus successive discrete values of the quantity being measured. The frequency of the known frequency source is made such that each measurement is presented as a direct digital representation of the quantity measured.

Variational symmetries, conserved quantities and identities for several equations of mathematical physics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Donchev, Veliko, E-mail: velikod@ie.bas.bg

2014-03-15

We find variational symmetries, conserved quantities and identities for several equations: envelope equation, Böcher equation, the propagation of sound waves with losses, flow of a gas with losses, and the nonlinear Schrödinger equation with losses or gains, and an electro-magnetic interaction. Most of these equations do not have a variational description with the classical variational principle and we find such a description with the generalized variational principle of Herglotz.

Understanding why an active video game intervention did not improve motor skill and physical activity in children with developmental coordination disorder: A quantity or quality issue?

PubMed

Howie, Erin K; Campbell, Amity C; Abbott, Rebecca A; Straker, Leon M

2017-01-01

Active video games (AVGs) have been identified as a novel strategy to improve motor skill and physical activity in clinical populations. A recent cross-over randomized trial found AVGs to be ineffective at improving motor skill and physical activity in the home-environment for children with or at-risk for developmental coordination disorder (DCD). The study purpose was to better understand why the intervention had been ineffective by examining the quantity and quality of AVG play during an AVG intervention for children with or at-risk for DCD. Participants (n=21, ages 9-12) completed the 16 week AVG intervention. Detailed quantitative and qualitative data were systematically triangulated to obtain the quantity of exposure (AVG exposure over time, patterns of exposure) and quality of use (game selection, facilitators and barriers to play). The median AVG dose (range 30-35min/day) remained relatively stable across the intervention and met the prescribed dose. Play quality was impacted by game selection, difficulty playing games, lack of time, illness, technical difficulties and boredom. The ineffectiveness of a home-based AVG intervention may be due to quality of play. Strategies to improve the quality of game play may help realize the potential benefits of AVGs as a clinical tool for children with DCD. Copyright © 2016 Elsevier Ltd. All rights reserved.

Characteristics of high-tension magnetos

NASA Technical Reports Server (NTRS)

Silsbee, F B

1920-01-01

This report gives the results of an investigation made into the fundamental physical characteristics of high-tension ignition magnetos, and also describes the methods used for measuring the quantities involved.

Special Issue. Return to Progress: A New Politics of Adult Education?

ERIC Educational Resources Information Center

Gurnah, Ahmed; And Others

1994-01-01

"Editorial" (Gurnah); "What Should Further Education Be Accountable For?" (Perry); "Women Not for Turning" (Rose); "Rooting Learning" (Yarnit); "Governors Hold the Key" (Searle); "Back on Track" (Miskin, Hartley); "Quality and Quantity in Higher Education" (Mitchell);…

Feasibility of a nuclear gauge for fuel quantity measurement aboard aircraft

NASA Technical Reports Server (NTRS)

Signh, J. J.; Mall, G. H.; Sprinkle, D. R.; Chegini, H.

1986-01-01

Capacitance fuel gauges have served as the basis for fuel quantity indicating systems in aircraft for several decades. However, there have been persistent reports by the airlines that these gauges often give faulty indications due to microbial growth and other contaminants in the fuel tanks. This report describes the results of a feasibility study of using gamma ray attenuation as the basis for measuring fuel quantity in the tanks. Studies with a weak Am-241 59.5-keV radiation source indicate that it is possible to continuously monitor the fuel quantity in the tanks to an accuracy of better than 1 percent. These measurements also indicate that there are easily measurable differences in the physical properties and resultant attenuation characteristics of JP-4, JP-5, and Jet A fuels. The experimental results, along with a suggested source-detector geometrical configuration are described.

Evolution of adaptation mechanisms: Adaptation energy, stress, and oscillating death.

PubMed

Gorban, Alexander N; Tyukina, Tatiana A; Smirnova, Elena V; Pokidysheva, Lyudmila I

2016-09-21

In 1938, Selye proposed the notion of adaptation energy and published 'Experimental evidence supporting the conception of adaptation energy.' Adaptation of an animal to different factors appears as the spending of one resource. Adaptation energy is a hypothetical extensive quantity spent for adaptation. This term causes much debate when one takes it literally, as a physical quantity, i.e. a sort of energy. The controversial points of view impede the systematic use of the notion of adaptation energy despite experimental evidence. Nevertheless, the response to many harmful factors often has general non-specific form and we suggest that the mechanisms of physiological adaptation admit a very general and nonspecific description. We aim to demonstrate that Selye׳s adaptation energy is the cornerstone of the top-down approach to modelling of non-specific adaptation processes. We analyze Selye׳s axioms of adaptation energy together with Goldstone׳s modifications and propose a series of models for interpretation of these axioms. Adaptation energy is considered as an internal coordinate on the 'dominant path' in the model of adaptation. The phenomena of 'oscillating death' and 'oscillating remission' are predicted on the base of the dynamical models of adaptation. Natural selection plays a key role in the evolution of mechanisms of physiological adaptation. We use the fitness optimization approach to study of the distribution of resources for neutralization of harmful factors, during adaptation to a multifactor environment, and analyze the optimal strategies for different systems of factors. Copyright © 2016 Elsevier Ltd. All rights reserved.

The importance of key floral bioactive compounds to honey bees for the detection and attraction of hybrid vegetable crops and increased seed yield.

PubMed

Mas, Flore; Harper, Aimee; Horner, Rachael; Welsh, Taylor; Jaksons, Peter; Suckling, David M

2018-02-15

Crop breeding programmes generally select for traits for improved yield and human consumption preferences. Yet, they often overlook one fundamental trait essential for insect-pollinated crops: pollinator attraction. This is even more critical for hybrid plants that rely on cross-pollination between the male-fertile line and the male-sterile line to set seeds. This study investigated the role of floral odours for honey bee pollination that could explain the poor seed yield in hybrid crops. The key floral bioactive compounds that honey bees detect were identified for three vegetable hybrid crops. It was found that 30% of the variation in bioactive compound quantities was explained by variety. Differences in quantities of the bioactive compounds triggered different degrees of olfactory response and were also associated with varied appetitive response. Correlating the abundance of each bioactive compound with seed yield, it was found that aldehydes such as nonanal and decanal can have a strong negative influence on seed yield with increasing quantity. Using these methodologies to identify relevant bioactive compounds associated with honey bee pollination, plant breeding programmes should also consider selecting for floral traits attractive to honey bees to improve crop pollination for enhanced seed yield. © 2018 Society of Chemical Industry. © 2018 Society of Chemical Industry.

Subatomic-scale force vector mapping above a Ge(001) dimer using bimodal atomic force microscopy

NASA Astrophysics Data System (ADS)

Naitoh, Yoshitaka; Turanský, Robert; Brndiar, Ján; Li, Yan Jun; Štich, Ivan; Sugawara, Yasuhiro

2017-07-01

Probing physical quantities on the nanoscale that have directionality, such as magnetic moments, electric dipoles, or the force response of a surface, is essential for characterizing functionalized materials for nanotechnological device applications. Currently, such physical quantities are usually experimentally obtained as scalars. To investigate the physical properties of a surface on the nanoscale in depth, these properties must be measured as vectors. Here we demonstrate a three-force-component detection method, based on multi-frequency atomic force microscopy on the subatomic scale and apply it to a Ge(001)-c(4 × 2) surface. We probed the surface-normal and surface-parallel force components above the surface and their direction-dependent anisotropy and expressed them as a three-dimensional force vector distribution. Access to the atomic-scale force distribution on the surface will enable better understanding of nanoscale surface morphologies, chemical composition and reactions, probing nanostructures via atomic or molecular manipulation, and provide insights into the behaviour of nano-machines on substrates.

Significance of touch for perceptions of parenting and psychological adjustment among adolescents.

PubMed

Pearce, C M; Martin, G; Wood, K

1995-02-01

This pilot study set out to investigate whether a relationship exists between differential quality and quantity of physical contact experience and perceptions of parenting, psychological adjustment, and suicidal behavior among adolescents. A self-report questionnaire assessed individuals' perceptions of how frequently they experienced pleasant (positive) and unpleasant (negative) touch from family and friends. Together with the Achenbach Youth Self-Report and the Parental Bonding Instrument, this questionnaire was administered to 142 male and 129 female students aged between 13 and 15 years (mean = 13.54, SD = 0.56) attending a randomly chosen metropolitan state high school and a coeducational private school. The major findings indicated that differential quality and quantity of physical contact experience was related to perceptions of parenting, psychological adjustment, and suicidal behavior, although a gender difference was observed. The findings suggest that physical contact experiences may reflect different parenting styles and may be a vulnerability factor for a range of difficulties among adolescents.

Recovering Galaxy Properties Using Gaussian Process SED Fitting

NASA Astrophysics Data System (ADS)

Iyer, Kartheik; Awan, Humna

2018-01-01

Information about physical quantities like the stellar mass, star formation rates, and ages for distant galaxies is contained in their spectral energy distributions (SEDs), obtained through photometric surveys like SDSS, CANDELS, LSST etc. However, noise in the photometric observations often is a problem, and using naive machine learning methods to estimate physical quantities can result in overfitting the noise, or converging on solutions that lie outside the physical regime of parameter space.We use Gaussian Process regression trained on a sample of SEDs corresponding to galaxies from a Semi-Analytic model (Somerville+15a) to estimate their stellar masses, and compare its performance to a variety of different methods, including simple linear regression, Random Forests, and k-Nearest Neighbours. We find that the Gaussian Process method is robust to noise and predicts not only stellar masses but also their uncertainties. The method is also robust in the cases where the distribution of the training data is not identical to the target data, which can be extremely useful when generalized to more subtle galaxy properties.

Simulation-based training for cardiac auscultation skills: systematic review and meta-analysis.

PubMed

McKinney, James; Cook, David A; Wood, David; Hatala, Rose

2013-02-01

The current review examines the effectiveness of simulation-based medical education (SBME) for training health professionals in cardiac physical examination and examines the relative effectiveness of key instructional design features. Data sources included a comprehensive, systematic search of MEDLINE, EMBASE, CINAHL, PsychINFO, ERIC, Web of Science, and Scopus through May 2011. Included studies investigated SBME to teach health profession learners cardiac physical examination skills using outcomes of knowledge or skill. We carried out duplicate assessment of study quality and data abstraction and pooled effect sizes using random effects. We identified 18 articles for inclusion. Thirteen compared SBME to no-intervention (either single group pre-post comparisons or SBME added to other instruction common to all learners, such as traditional bedside teaching), three compared SBME to other educational interventions, and two compared two SBME interventions. Meta-analysis of the 13 no-intervention comparison studies demonstrated that simulation-based instruction in cardiac auscultation was effective, with pooled effect sizes of 1.10 (95 % CI 0.49-1.72; p < 0.001; I(2) = 92.4 %) for knowledge outcomes and 0.87 (95 % CI 0.52-1.22; p < 0.001; I(2) = 91.5 %) for skills. In sub-group analysis, hands-on practice with the simulator appeared to be an important teaching technique. Narrative review of the comparative effectiveness studies suggests that SBME may be of similar effectiveness to other active educational interventions, but more studies are required. The quantity of published evidence and the relative lack of comparative effectiveness studies limit this review. SBME is an effective educational strategy for teaching cardiac auscultation. Future studies should focus on comparing key instructional design features and establishing SBME's relative effectiveness compared to other educational interventions.

Western USA Groundwater Regulation and Infrastructure for Irrigated Agriculture

NASA Astrophysics Data System (ADS)

Perrone, D.; Jasechko, S.; Nelson, R.

2016-12-01

More than 2/3 of US groundwater use is attributed to the western 17 states—an area with many key regions for agricultural production and unsustainable groundwater pumping. Although there is increasing acknowledgement of the importance of more intensive management, the western US remains a patchwork of diverse and imperfect governance and legal strategies. Water quantity is regulated at the state level, so obtaining the right to withdrawal groundwater ("permitting") can be vastly different from one state to the next. Much attention has been devoted to quantifying rates of groundwater depletion across the west, but little is known about the spatiotemporal patterns of groundwater drilling and permitting. While many local agencies have a plethora of knowledge about groundwater infrastructure and regulation, most of this knowledge is hearsay or locally disseminated, and it is difficult to obtain groundwater data—physical and legal—comprehensively across large regions. Here we explore and map groundwater infrastructure and permitting approaches across the western US, focusing specifically on the importance of groundwater to sustaining agriculture in key producing regions (e.g., High Plains). We analyze over four million groundwater-drilling records and relate these data to geographically defined subareas ("special permitting areas") within states that have been designated legally due to concerns about the effects of groundwater withdrawal. Our work indicates that the default set of laws and regulations within states is often of lesser importance because of the extent of and legal powers granted within special permitting areas. We also find areas with significant groundwater drilling that do not fall within special permitting areas, indicating that special permitting areas are not all-inclusive of intensive use. Our work has practical implications, highlighting the effects of regionalized laws on a resource not confined physically by jurisdictional boundaries.

Water analysis in a lab-on-a-chip system

NASA Astrophysics Data System (ADS)

Freimuth, Herbert; von Germar, Frithjof; Frese, Ines; Nahrstedt, Elzbieta; Küpper, Michael; Schenk, Rainer; Baser, Björn; Ott, Johannes; Drese, Klaus; Detemple, Peter; Doll, Theodor

2006-01-01

The development of a lab-on-chip system which allows the parallel detection of a variety of different parameters of a water sample is presented. Water analysis typically comprises the determination of around 30 physical and chemical parameters. An even larger number can arise when special contaminations of organic molecules are of interest. A demonstration system has been realised to show the feasibility and performance of an integrated device for the determination of physical quantities like electrical conductivity, light absorption and turbidity. Additionally, chemical quantities like the pH-value and the content of inorganic and organic contaminations are also determined. Two chips of credit card size contain the analytical functions and will be fabricated by injection moulding. First prototypes have been manufactured by milling or precision milling for the optical components.

Polymer alloys with balanced heat storage capacity and engineering attributes and applications thereof

DOEpatents

Soroushian, Parviz

2002-01-01

A thermoplastic polymer of relatively low melt temperature is blended with at least one of thermosets, elastomers, and thermoplastics of relatively high melt temperature in order to produce a polymer blend which absorbs relatively high quantities of latent heat without melting or major loss of physical and mechanical characteristics as temperature is raised above the melting temperature of the low-melt-temperature thermoplastic. The polymer blend can be modified by the addition of at least one of fillers, fibers, fire retardants, compatibilisers, colorants, and processing aids. The polymer blend may be used in applications where advantage can be taken of the absorption of excess heat by a component which remains solid and retains major fractions of its physical and mechanical characteristics while absorbing relatively high quantities of latent heat.

Optimal production lot size and reorder point of a two-stage supply chain while random demand is sensitive with sales teams' initiatives

NASA Astrophysics Data System (ADS)

Sankar Sana, Shib

2016-01-01

The paper develops a production-inventory model of a two-stage supply chain consisting of one manufacturer and one retailer to study production lot size/order quantity, reorder point sales teams' initiatives where demand of the end customers is dependent on random variable and sales teams' initiatives simultaneously. The manufacturer produces the order quantity of the retailer at one lot in which the procurement cost per unit quantity follows a realistic convex function of production lot size. In the chain, the cost of sales team's initiatives/promotion efforts and wholesale price of the manufacturer are negotiated at the points such that their optimum profits reached nearer to their target profits. This study suggests to the management of firms to determine the optimal order quantity/production quantity, reorder point and sales teams' initiatives/promotional effort in order to achieve their maximum profits. An analytical method is applied to determine the optimal values of the decision variables. Finally, numerical examples with its graphical presentation and sensitivity analysis of the key parameters are presented to illustrate more insights of the model.

Enthalpy of Vaporization by Gas Chromatography: A Physical Chemistry Experiment

ERIC Educational Resources Information Center

Ellison, Herbert R.

2005-01-01

An experiment is conducted to measure the enthalpy of vaporization of volatile compounds like methylene chloride, carbon tetrachloride, and others by using gas chromatography. This physical property was measured using a very tiny quantity of sample revealing that it is possible to measure the enthalpies of two or more compounds at the same time.

Project Physics Programmed Instruction, Vectors 1.

ERIC Educational Resources Information Center

Harvard Univ., Cambridge, MA. Harvard Project Physics.

This programmed instruction booklet is an interim version of instructional materials being developed by Harvard Project Physics. It is the first in a series of three booklets on vectors and covers the definitions of vectors and scalars, drawing vector quantities to scale, and negative vectors. For others in this series, see SE 015 550 and SE 015…

Patterns of Response Times and Response Choices to Science Questions: The Influence of Relative Processing Time

ERIC Educational Resources Information Center

Heckler, Andrew F.; Scaife, Thomas M.

2015-01-01

We report on five experiments investigating response choices and response times to simple science questions that evoke student "misconceptions," and we construct a simple model to explain the patterns of response choices. Physics students were asked to compare a physical quantity represented by the slope, such as speed, on simple physics…

Quantity, Type, and Correlates of Physical Activity among American Middle Eastern University Students

ERIC Educational Resources Information Center

Kahan, David

2009-01-01

The prevalence of hypokinetic disease among persons of Middle Eastern heritage is higher than whites and research on American young adults of this population is limited. Therefore 214 tertiary students of Middle Eastern descent self-reported their physical activity (PA) over a 1-week monitoring period using pedometers and daily activity logs.…

Recent progress in Fourier Transform Infrared (FTIR) spectroscopy study of compositional, structural, and physical attributes of developmental cotton fibers

USDA-ARS?s Scientific Manuscript database

Cotton fibers are natural plant products and their end-use qualities depend on their stages of development. In general, the quantity of natural fiber cellulose I (ß 1'4 linked glucose residues) increases rapidly, thus it leads to compositional, structural, and physical attribute variations among the...

Rainsticks: Integrating Culture, Folklore, and the Physics of Sound

ERIC Educational Resources Information Center

Moseley, Christine; Fies, Carmen

2007-01-01

The purpose of this activity is for students to build a rainstick out of materials in their own environment and imitate the sound of rain while investigating the physical principles of sound. Students will be able to relate the sound produced by an instrument to the type and quantity of materials used in its construction.

Continuous generation and stabilization of mesoscopic field superposition states in a quantum circuit

NASA Astrophysics Data System (ADS)

Roy, Ananda; Leghtas, Zaki; Stone, A. Douglas; Devoret, Michel; Mirrahimi, Mazyar

2015-01-01

While dissipation is widely considered to be harmful for quantum coherence, it can, when properly engineered, lead to the stabilization of nontrivial pure quantum states. We propose a scheme for continuous generation and stabilization of Schrödinger cat states in a cavity using dissipation engineering. We first generate nonclassical photon states with definite parity by means of a two-photon drive and dissipation, and then stabilize these transient states against single-photon decay. The single-photon stabilization is autonomous, and is implemented through a second engineered bath, which exploits the photon-number-dependent frequency splitting due to Kerr interactions in the strongly dispersive regime of circuit QED. Starting with the Hamiltonian of the baths plus cavity, we derive an effective model of only the cavity photon states along with analytic expressions for relevant physical quantities, such as the stabilization rate. The deterministic generation of such cat states is one of the key ingredients in performing universal quantum computation.

Improved Limits for Higgs-Portal Dark Matter from LHC Searches.

PubMed

Hoferichter, Martin; Klos, Philipp; Menéndez, Javier; Schwenk, Achim

2017-11-03

Searches for invisible Higgs decays at the Large Hadron Collider constrain dark matter Higgs-portal models, where dark matter interacts with the standard model fields via the Higgs boson. While these searches complement dark matter direct-detection experiments, a comparison of the two limits depends on the coupling of the Higgs boson to the nucleons forming the direct-detection nuclear target, typically parametrized in a single quantity f_{N}. We evaluate f_{N} using recent phenomenological and lattice-QCD calculations, and include for the first time the coupling of the Higgs boson to two nucleons via pion-exchange currents. We observe a partial cancellation for Higgs-portal models that makes the two-nucleon contribution anomalously small. Our results, summarized as f_{N}=0.308(18), show that the uncertainty of the Higgs-nucleon coupling has been vastly overestimated in the past. The improved limits highlight that state-of-the-art nuclear physics input is key to fully exploiting experimental searches.

Flowers under pressure: ins and outs of turgor regulation in development

PubMed Central

Beauzamy, Léna; Nakayama, Naomi; Boudaoud, Arezki

2014-01-01

Background Turgor pressure is an essential feature of plants; however, whereas its physiological importance is unequivocally recognized, its relevance to development is often reduced to a role in cell elongation. Scope This review surveys the roles of turgor in development, the molecular mechanisms of turgor regulation and the methods used to measure turgor and related quantities, while also covering the basic concepts associated with water potential and water flow in plants. Three key processes in flower development are then considered more specifically: flower opening, anther dehiscence and pollen tube growth. Conclusions Many molecular determinants of turgor and its regulation have been characterized, while a number of methods are now available to quantify water potential, turgor and hydraulic conductivity. Data on flower opening, anther dehiscence and lateral root emergence suggest that turgor needs to be finely tuned during development, both spatially and temporally. It is anticipated that a combination of biological experiments and physical measurements will reinforce the existing data and reveal unexpected roles of turgor in development. PMID:25288632

Resource acquisition, distribution and end-use efficiencies and the growth of industrial society

NASA Astrophysics Data System (ADS)

Jarvis, A.; Jarvis, S.; Hewitt, N.

2015-01-01

A key feature of the growth of industrial society is the acquisition of increasing quantities of resources from the environment and their distribution for end use. With respect to energy, growth has been near exponential for the last 160 years. We attempt to show that the global distribution of resources that underpins this growth may be facilitated by the continual development and expansion of near optimal directed networks. If so, the distribution efficiencies of these networks must decline as they expand due to path lengths becoming longer and more tortuous. To maintain long-term exponential growth the physical limits placed on the distribution networks appear to be counteracted by innovations deployed elsewhere in the system: namely at the points of acquisition and end use. We postulate that the maintenance of growth at the specific rate of ~2.4% yr-1 stems from an implicit desire to optimise patterns of energy use over human working lifetimes.

Computational attributes of the integral form of the equation of transfer

NASA Technical Reports Server (NTRS)

Frankel, J. I.

1991-01-01

Difficulties can arise in radiative and neutron transport calculations when a highly anisotropic scattering phase function is present. In the presence of anisotropy, currently used numerical solutions are based on the integro-differential form of the linearized Boltzmann transport equation. This paper, departs from classical thought and presents an alternative numerical approach based on application of the integral form of the transport equation. Use of the integral formalism facilitates the following steps: a reduction in dimensionality of the system prior to discretization, the use of symbolic manipulation to augment the computational procedure, and the direct determination of key physical quantities which are derivable through the various Legendre moments of the intensity. The approach is developed in the context of radiative heat transfer in a plane-parallel geometry, and results are presented and compared with existing benchmark solutions. Encouraging results are presented to illustrate the potential of the integral formalism for computation. The integral formalism appears to possess several computational attributes which are well-suited to radiative and neutron transport calculations.

Transformative Relation of Kinematical Descriptive Quantities Defined by Different Spatial Referential Frame, Its Property and Application

NASA Astrophysics Data System (ADS)

Luo, Ji

2012-08-01

Quantitative transformations between corresponding kinetic quantities defined by any two spatial referential frames, whose relative kinematics relations (purely rotational and translational movement) are known, are presented based on necessarily descriptive definitions of the fundamental concepts (instant, time, spatial referential frame that distinguishes from Maths. Coordination, physical point) had being clarified by directly empirical observation with artificially descriptive purpose. Inductive investigation of the transformation reveals that all physical quantities such as charge, temperature, time, volume, length, temporal rate of the quantities and relations like temporal relation between signal source and observer as such are independent to spatial frames transformation except above kinematical quantities transformations, kinematics related dynamics such as Newton ’ s second law existing only in inertial frames and exchange of kinetic energy of mass being valid only in a selected inertial frame. From above bas is, we demonstrate a series of inferences and applications such as phase velocity of light being direct respect to medium (including vacuum) rather than to the frame, using spatial referential frame to describe any measurable field (electric field, magnetic field, gravitational field) and the field ’ s variation; and have tables to contrast and evaluate all aspects of those hypotheses related with spacetime such as distorted spacetime around massive stellar, four dimension spacetime, gravitational time dilation and non - Euclid geometry with new one. The demonstration strongly suggests all the hypotheses are invalid in capable tested concepts ’ meaning and relations. The conventional work on frame transformation and its property, hypothesized by Voigt, Heaviside, Lorentz, Poincare and Einstein a century ago with some mathematical speculation lacking rigorous definition of the fundamental concepts such as instant, time, spatial reference, straight line, plane area, merely good in building up patchwork to do self p referred explanation by making up derivative concepts or accumulating new hypothesis, has disturbed people to describe the physical nature by setting up the sound basis of concept and relations with capable tested method, it’s time to be replaced by empirically effective alternative.

Differences in the early cognitive development of children and great apes.

PubMed

Wobber, Victoria; Herrmann, Esther; Hare, Brian; Wrangham, Richard; Tomasello, Michael

2014-04-01

There is very little research comparing great ape and human cognition developmentally. In the current studies we compared a cross-sectional sample of 2- to 4-year-old human children (n=48) with a large sample of chimpanzees and bonobos in the same age range (n=42, hereafter: apes) on a broad array of cognitive tasks. We then followed a group of juvenile apes (n=44) longitudinally over 3 years to track their cognitive development in greater detail. In skills of physical cognition (space, causality, quantities), children and apes performed comparably at 2 years of age, but by 4 years of age children were more advanced (whereas apes stayed at their 2-year-old performance levels). In skills of social cognition (communication, social learning, theory of mind), children out-performed apes already at 2 years, and increased this difference even more by 4 years. Patterns of development differed more between children and apes in the social domain than the physical domain, with support for these patterns present in both the cross-sectional and longitudinal ape data sets. These results indicate key differences in the pattern and pace of cognitive development between humans and other apes, particularly in the early emergence of specific social cognitive capacities in humans. Copyright © 2013 Wiley Periodicals, Inc.

A feeling for the numbers in biology

PubMed Central

Phillips, Rob; Milo, Ron

2009-01-01

Although the quantitative description of biological systems has been going on for centuries, recent advances in the measurement of phenomena ranging from metabolism to gene expression to signal transduction have resulted in a new emphasis on biological numeracy. This article describes the confluence of two different approaches to biological numbers. First, an impressive array of quantitative measurements make it possible to develop intuition about biological numbers ranging from how many gigatons of atmospheric carbon are fixed every year in the process of photosynthesis to the number of membrane transporters needed to provide sugars to rapidly dividing Escherichia coli cells. As a result of the vast array of such quantitative data, the BioNumbers web site has recently been developed as a repository for biology by the numbers. Second, a complementary and powerful tradition of numerical estimates familiar from the physical sciences and canonized in the so-called “Fermi problems” calls for efforts to estimate key biological quantities on the basis of a few foundational facts and simple ideas from physics and chemistry. In this article, we describe these two approaches and illustrate their synergism in several particularly appealing case studies. These case studies reveal the impact that an emphasis on numbers can have on important biological questions. PMID:20018695

Chemical Data Reporting Fact Sheet: Basic Information

EPA Pesticide Factsheets

EPA collects information on the types and quantities of chemicals produced in the U.S under the Chemical Data Reporting (CDR) requirements. This fact sheet outlines key information about CDR, including what data are collected and how the data are used.

The Impact of the Evolving Satellite Data Record on Reanalysis Water and Energy Fluxes During the Past 30 Years

NASA Technical Reports Server (NTRS)

Robertson, Franklin R.; Miller, T. L.; Bosilovich, M. G.; Chen, J.

2010-01-01

Retrospective analyses (reanalyses) use a fixed assimilation model to take diverse observations and synthesize consistent, time-dependent fields of state variables and fluxes (e.g. temperature, moisture, momentum, turbulent and radiative fluxes). Because they offer data sets of these quantities at regular space / time intervals, atmospheric reanalyses have become a mainstay of the climate community for diagnostic purposes and for driving offline ocean and land models. Of course, one weakness of these data sets is the susceptibility of the flux products to uncertainties because of shortcomings in parameterized model physics. Another issue, perhaps less appreciated, is the fact that the discreet changes in the evolving observational system, particularly from satellite sensors, may also introduce artifacts in the time series of quantities. In this paper we examine the ability of the NASA MERRA (Modern Era Retrospective Analysis for Research and Applications) and other recent reanalyses to determine variability in the climate system over the satellite record ( the last 30 years). In particular we highlight the effect on reanalyses of discontinuities at the junctures of the onset of passive microwave imaging (Special Sensor Microwave Imager) in late 1987 as well as improved sounding and imaging with the Advanced Microwave Sounding Unit, AMSU-A, in 1998. We examine these data sets from two perspectives. The first is the ability to capture modes of variability that have coherent spatial structure (e.g. ENSO events and near-decadal coupling to SST changes) and how these modes are contained within trends in near global averages of key quantities. Secondly, we consider diagnostics that measure the consistency in energetic scaling in the hydrologic cycle, particularly the fractional changes in column-integrated water vapor versus precipitation as they are coupled to radiative flux constraints. These results will be discussed in the context of implications for science objectives and priorities of the NASA Energy and Water Cycle Study, NEWS.

Reply to "Comment on `Optical Imaging of Light-Induced Thermopower in Semiconductors'"

NASA Astrophysics Data System (ADS)

Gibelli, François; Lombez, Laurent; Rodière, Jean; Guillemoles, Jean-François

2018-05-01

In a Comment [1] on our previously published article [2], Apertet stated, "The definition of the thermopower given in that article seems erroneous due to a confusion between the different physical quantities needed to derive this parameter." We believe some definitions need to be clarified in order to avoid confusion. We here intend to answer the questions of Apertet by detailing the method and by focusing on the definition of the quantities that we optically measured.

Optical radiation measurements: instrumentation and sources of error.

PubMed

Landry, R J; Andersen, F A

1982-07-01

Accurate measurement of optical radiation is required when sources of this radiation are used in biological research. The most difficult measurements of broadband noncoherent optical radiations usually must be performed by a highly trained specialist using sophisticated, complex, and expensive instruments. Presentation of the results of such measurement requires correct use of quantities and units with which many biological researchers are unfamiliar. The measurement process, physical quantities and units, measurement systems with instruments, and sources of error and uncertainties associated with optical radiation measurements are reviewed.

Exploiting active subspaces to quantify uncertainty in the numerical simulation of the HyShot II scramjet

NASA Astrophysics Data System (ADS)

Constantine, P. G.; Emory, M.; Larsson, J.; Iaccarino, G.

2015-12-01

We present a computational analysis of the reactive flow in a hypersonic scramjet engine with focus on effects of uncertainties in the operating conditions. We employ a novel methodology based on active subspaces to characterize the effects of the input uncertainty on the scramjet performance. The active subspace identifies one-dimensional structure in the map from simulation inputs to quantity of interest that allows us to reparameterize the operating conditions; instead of seven physical parameters, we can use a single derived active variable. This dimension reduction enables otherwise infeasible uncertainty quantification, considering the simulation cost of roughly 9500 CPU-hours per run. For two values of the fuel injection rate, we use a total of 68 simulations to (i) identify the parameters that contribute the most to the variation in the output quantity of interest, (ii) estimate upper and lower bounds on the quantity of interest, (iii) classify sets of operating conditions as safe or unsafe corresponding to a threshold on the output quantity of interest, and (iv) estimate a cumulative distribution function for the quantity of interest.

The International System of Units (SI) in Oceanography. Report of IAPSO Working Group on Symbols, Units and Nomenclature in Physical Oceanography (SUN). Unesco Technical Papers in Marine Science 45. IAPSO Publication Scientifique No. 32.

ERIC Educational Resources Information Center

United Nations Educational, Scientific, and Cultural Organization, Paris (France). Div. of Marine Sciences.

This report introduces oceanographers to the International System of Units (SI) in physical oceanography. The SI constitutes a universal language, designed to be understood by all scientists. It facilitates their mutual comprehension and exchange of views and results of their work. The first part of the report is devoted to physical quantities,…

Fluid Motion in a Spinning, Coning Cylinder via Spatial Eigenfunction Expansion.

DTIC Science & Technology

1987-08-01

PRESSURE AND MOMENT COEFFICIENTS The velocity, pressure and moment exerted by the liquid on the container are quantities of physical interest calculated...with collocation; these are denoted by LS and COL, respectively. Of the physical parameters, the calculation is more sensitive to Re and f than A...Applied Ntate’atics and Physics (ZAMP), Vol. 33, pp. 189-201, March 1982. 4I REFERENCES (continued) 13. Gerber, N., and Sedney, R., "Moment on a

Magnetic field line random walk in two-dimensional dynamical turbulence

NASA Astrophysics Data System (ADS)

Wang, J. F.; Qin, G.; Ma, Q. M.; Song, T.; Yuan, S. B.

2017-08-01

The field line random walk (FLRW) of magnetic turbulence is one of the important topics in plasma physics and astrophysics. In this article, by using the field line tracing method, the mean square displacement (MSD) of FLRW is calculated on all possible length scales for pure two-dimensional turbulence with the damping dynamical model. We demonstrate that in order to describe FLRW with the damping dynamical model, a new dimensionless quantity R is needed to be introduced. On different length scales, dimensionless MSD shows different relationships with the dimensionless quantity R. Although the temporal effect affects the MSD of FLRW and even changes regimes of FLRW, it does not affect the relationship between the dimensionless MSD and dimensionless quantity R on all possible length scales.

Approximate solutions to Mathieu's equation

NASA Astrophysics Data System (ADS)

Wilkinson, Samuel A.; Vogt, Nicolas; Golubev, Dmitry S.; Cole, Jared H.

2018-06-01

Mathieu's equation has many applications throughout theoretical physics. It is especially important to the theory of Josephson junctions, where it is equivalent to Schrödinger's equation. Mathieu's equation can be easily solved numerically, however there exists no closed-form analytic solution. Here we collect various approximations which appear throughout the physics and mathematics literature and examine their accuracy and regimes of applicability. Particular attention is paid to quantities relevant to the physics of Josephson junctions, but the arguments and notation are kept general so as to be of use to the broader physics community.

Autism and Pervasive Developmental Disorders

ERIC Educational Resources Information Center

Volkmar, Fred R.; Lord, Catherine; Bailey, Anthony; Schultz, Robert T.; Klin, Ami

2004-01-01

The quantity and quality of research into autism and related conditions have increased dramatically in recent years. Consequently we selectively review key accomplishments and highlight directions for future research. More consistent approaches to diagnosis and more rigorous assessment methods have significantly advanced research, although the…

Physics that Textbook Writers Usually Get Wrong: III.

ERIC Educational Resources Information Center

Bauman, Robert P.

1992-01-01

Examines inconsistencies in science textbook discussions of vector quantities and force. Provides illustrations of textbook inconsistencies related to Newton's laws of motion and the concepts of centrifugal and coriolis force. (MDH)

Hamiltonian lattice field theory: Computer calculations using variational methods

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zako, Robert L.

1991-12-03

I develop a variational method for systematic numerical computation of physical quantities -- bound state energies and scattering amplitudes -- in quantum field theory. An infinite-volume, continuum theory is approximated by a theory on a finite spatial lattice, which is amenable to numerical computation. I present an algorithm for computing approximate energy eigenvalues and eigenstates in the lattice theory and for bounding the resulting errors. I also show how to select basis states and choose variational parameters in order to minimize errors. The algorithm is based on the Rayleigh-Ritz principle and Kato`s generalizations of Temple`s formula. The algorithm could bemore » adapted to systems such as atoms and molecules. I show how to compute Green`s functions from energy eigenvalues and eigenstates in the lattice theory, and relate these to physical (renormalized) coupling constants, bound state energies and Green`s functions. Thus one can compute approximate physical quantities in a lattice theory that approximates a quantum field theory with specified physical coupling constants. I discuss the errors in both approximations. In principle, the errors can be made arbitrarily small by increasing the size of the lattice, decreasing the lattice spacing and computing sufficiently long. Unfortunately, I do not understand the infinite-volume and continuum limits well enough to quantify errors due to the lattice approximation. Thus the method is currently incomplete. I apply the method to real scalar field theories using a Fock basis of free particle states. All needed quantities can be calculated efficiently with this basis. The generalization to more complicated theories is straightforward. I describe a computer implementation of the method and present numerical results for simple quantum mechanical systems.« less

Effects of Caregiver Status, Coping Styles, and Social Support on the Physical Health of Korean American Caregivers

ERIC Educational Resources Information Center

Kim, Jung-Hyun; Knight, Bob G.

2008-01-01

Purpose: This study investigated direct and indirect effects of caregiver status on the physical health of Korean American caregivers in terms of caregiver coping styles and the quantity and the quality of informal social support. Design and Methods: Using a sample of 87 caregivers and 87 matched noncaregivers, we analyzed a path model, employing…

Public Disclosure to Improve Physical Education in an Urban School District: Results from a 2-year Quasi-Experimental Study

ERIC Educational Resources Information Center

Thompson, Hannah R.; Vittinghoff, Eric; Linchey, Jennifer K.; Madsen, Kristine A.

2015-01-01

Background: Many elementary schools have policies requiring a minimum amount of physical education (PE). However, few schools comply with local/state PE policy and little is known about how to improve adherence. We evaluated changes in PE among fifth-grade classes, following participatory action research efforts to improve PE quantity and policy…

10 CFR 73.35 - Requirements for physical protection of irradiated reactor fuel (100 grams or less) in transit.

Code of Federal Regulations, 2014 CFR

2014-01-01

... fuel (100 grams or less) in transit. 73.35 Section 73.35 Energy NUCLEAR REGULATORY COMMISSION... Transit § 73.35 Requirements for physical protection of irradiated reactor fuel (100 grams or less) in... quantity of irradiated reactor fuel weighing 100 grams (0.22 pounds) or less in net weight of irradiated...

A Cluster-Analytical Approach towards Physical Activity and Eating Habits among 10-Year-Old Children

ERIC Educational Resources Information Center

Sabbe, Dieter; De Bourdeaudhuij, I.; Legiest, E.; Maes, L.

2008-01-01

The purpose was to investigate whether clusters--based on physical activity (PA) and eating habits--can be found among children, and to explore subgroups' characteristics. A total of 1725 10-year olds completed a self-administered questionnaire. K-means cluster analysis was based on the weekly quantity of vigorous and moderate PA, the excess index…

Overview of Nuclear Physics Data: Databases, Web Applications and Teaching Tools

NASA Astrophysics Data System (ADS)

McCutchan, Elizabeth

2017-01-01

The mission of the United States Nuclear Data Program (USNDP) is to provide current, accurate, and authoritative data for use in pure and applied areas of nuclear science and engineering. This is accomplished by compiling, evaluating, and disseminating extensive datasets. Our main products include the Evaluated Nuclear Structure File (ENSDF) containing information on nuclear structure and decay properties and the Evaluated Nuclear Data File (ENDF) containing information on neutron-induced reactions. The National Nuclear Data Center (NNDC), through the website www.nndc.bnl.gov, provides web-based retrieval systems for these and many other databases. In addition, the NNDC hosts several on-line physics tools, useful for calculating various quantities relating to basic nuclear physics. In this talk, I will first introduce the quantities which are evaluated and recommended in our databases. I will then outline the searching capabilities which allow one to quickly and efficiently retrieve data. Finally, I will demonstrate how the database searches and web applications can provide effective teaching tools concerning the structure of nuclei and how they interact. Work supported by the Office of Nuclear Physics, Office of Science of the U.S. Department of Energy under Contract No. DE-AC02-98CH10886.

Prediction of AL and Dst Indices from ACE Measurements Using Hybrid Physics/Black-Box Techniques

NASA Astrophysics Data System (ADS)

Spencer, E.; Rao, A.; Horton, W.; Mays, L.

2008-12-01

ACE measurements of the solar wind velocity, IMF and proton density is used to drive a hybrid Physics/Black- Box model of the nightside magnetosphere. The core physics is contained in a low order nonlinear dynamical model of the nightside magnetosphere called WINDMI. The model is augmented by wavelet based nonlinear mappings between the solar wind quantities and the input into the physics model, followed by further wavelet based mappings of the model output field aligned currents onto the ground based magnetometer measurements of the AL index and Dst index. The black box mappings are introduced at the input stage to account for uncertainties in the way the solar wind quantities are transported from the ACE spacecraft at L1 to the magnetopause. Similar mappings are introduced at the output stage to account for a spatially and temporally varying westward auroral electrojet geometry. The parameters of the model are tuned using a genetic algorithm, and trained using the large geomagnetic storm dataset of October 3-7 2000. It's predictive performance is then evaluated on subsequent storm datasets, in particular the April 15-24 2002 storm. This work is supported by grant NSF 7020201

Not Normal: the uncertainties of scientific measurements

NASA Astrophysics Data System (ADS)

Bailey, David C.

2017-01-01

Judging the significance and reproducibility of quantitative research requires a good understanding of relevant uncertainties, but it is often unclear how well these have been evaluated and what they imply. Reported scientific uncertainties were studied by analysing 41 000 measurements of 3200 quantities from medicine, nuclear and particle physics, and interlaboratory comparisons ranging from chemistry to toxicology. Outliers are common, with 5σ disagreements up to five orders of magnitude more frequent than naively expected. Uncertainty-normalized differences between multiple measurements of the same quantity are consistent with heavy-tailed Student's t-distributions that are often almost Cauchy, far from a Gaussian Normal bell curve. Medical research uncertainties are generally as well evaluated as those in physics, but physics uncertainty improves more rapidly, making feasible simple significance criteria such as the 5σ discovery convention in particle physics. Contributions to measurement uncertainty from mistakes and unknown problems are not completely unpredictable. Such errors appear to have power-law distributions consistent with how designed complex systems fail, and how unknown systematic errors are constrained by researchers. This better understanding may help improve analysis and meta-analysis of data, and help scientists and the public have more realistic expectations of what scientific results imply.

Not Normal: the uncertainties of scientific measurements

PubMed Central

2017-01-01

Judging the significance and reproducibility of quantitative research requires a good understanding of relevant uncertainties, but it is often unclear how well these have been evaluated and what they imply. Reported scientific uncertainties were studied by analysing 41 000 measurements of 3200 quantities from medicine, nuclear and particle physics, and interlaboratory comparisons ranging from chemistry to toxicology. Outliers are common, with 5σ disagreements up to five orders of magnitude more frequent than naively expected. Uncertainty-normalized differences between multiple measurements of the same quantity are consistent with heavy-tailed Student’s t-distributions that are often almost Cauchy, far from a Gaussian Normal bell curve. Medical research uncertainties are generally as well evaluated as those in physics, but physics uncertainty improves more rapidly, making feasible simple significance criteria such as the 5σ discovery convention in particle physics. Contributions to measurement uncertainty from mistakes and unknown problems are not completely unpredictable. Such errors appear to have power-law distributions consistent with how designed complex systems fail, and how unknown systematic errors are constrained by researchers. This better understanding may help improve analysis and meta-analysis of data, and help scientists and the public have more realistic expectations of what scientific results imply. PMID:28280557

Particle Dark Matter constraints: the effect of Galactic uncertainties

DOE Office of Scientific and Technical Information (OSTI.GOV)

Benito, Maria; Bernal, Nicolás; Iocco, Fabio

2017-02-01

Collider, space, and Earth based experiments are now able to probe several extensions of the Standard Model of particle physics which provide viable dark matter candidates. Direct and indirect dark matter searches rely on inputs of astrophysical nature, such as the local dark matter density or the shape of the dark matter density profile in the target in object. The determination of these quantities is highly affected by astrophysical uncertainties. The latter, especially those for our own Galaxy, are ill-known, and often not fully accounted for when analyzing the phenomenology of particle physics models. In this paper we present amore » systematic, quantitative estimate of how astrophysical uncertainties on Galactic quantities (such as the local galactocentric distance, circular velocity, or the morphology of the stellar disk and bulge) propagate to the determination of the phenomenology of particle physics models, thus eventually affecting the determination of new physics parameters. We present results in the context of two specific extensions of the Standard Model (the Singlet Scalar and the Inert Doublet) that we adopt as case studies for their simplicity in illustrating the magnitude and impact of such uncertainties on the parameter space of the particle physics model itself. Our findings point toward very relevant effects of current Galactic uncertainties on the determination of particle physics parameters, and urge a systematic estimate of such uncertainties in more complex scenarios, in order to achieve constraints on the determination of new physics that realistically include all known uncertainties.« less

Some conservation issues for the dynamical cores of NWP and climate models

NASA Astrophysics Data System (ADS)

Thuburn, J.

2008-03-01

The rationale for designing atmospheric numerical model dynamical cores with certain conservation properties is reviewed. The conceptual difficulties associated with the multiscale nature of realistic atmospheric flow, and its lack of time-reversibility, are highlighted. A distinction is made between robust invariants, which are conserved or nearly conserved in the adiabatic and frictionless limit, and non-robust invariants, which are not conserved in the limit even though they are conserved by exactly adiabatic frictionless flow. For non-robust invariants, a further distinction is made between processes that directly transfer some quantity from large to small scales, and processes involving a cascade through a continuous range of scales; such cascades may either be explicitly parameterized, or handled implicitly by the dynamical core numerics, accepting the implied non-conservation. An attempt is made to estimate the relative importance of different conservation laws. It is argued that satisfactory model performance requires spurious sources of a conservable quantity to be much smaller than any true physical sources; for several conservable quantities the magnitudes of the physical sources are estimated in order to provide benchmarks against which any spurious sources may be measured.

Investigations of the pushability behavior of cardiovascular angiographic catheters.

PubMed

Bloss, Peter; Rothe, Wolfgang; Wünsche, Peter; Werner, Christian; Rothe, Alexander; Kneissl, Georg Dieter; Burger, Wolfram; Rehberg, Elisabeth

2003-01-01

The placement of angiographic catheters into the vascular system is a routine procedure in modern clinical business. The definition of objective but not yet available evaluation protocols based on measurable physical quantities correlated to the empirical clinical findings is of utmost importance for catheter manufacturers for in-house product screening and optimization. In this context, we present an assessment of multiple mechanical and surface catheter properties such as static and kinetic friction, bending stiffness, microscopic surface topology, surface roughness, surface free energy and their interrelation. Theoretical framework, description of experimental methods and extensive data measured on several different catheters are provided and in conclusion a testing procedure is defined. Although this procedure is based on the measurement of several physical quantities it can be easily implemented by commercial laboratories testing catheters as it is based on relatively low-cost standard methods.

A multiscale strength model for tantalum over an extended range of strain rates

NASA Astrophysics Data System (ADS)

Barton, N. R.; Rhee, M.

2013-09-01

A strength model for tantalum is developed and exercised across a range of conditions relevant to various types of experimental observations. The model is based on previous multiscale modeling work combined with experimental observations. As such, the model's parameterization includes a hybrid of quantities that arise directly from predictive sub-scale physics models and quantities that are adjusted to align the model with experimental observations. Given current computing and experimental limitations, the response regions for sub-scale physics simulations and detailed experimental observations have been largely disjoint. In formulating the new model and presenting results here, attention is paid to integrated experimental observations that probe strength response at the elevated strain rates where a previous version of the model has generally been successful in predicting experimental data [Barton et al., J. Appl. Phys. 109(7), 073501 (2011)].

A Systematic Review of Mapping Strategies for the Sonification of Physical Quantities

PubMed Central

Dubus, Gaël; Bresin, Roberto

2013-01-01

The field of sonification has progressed greatly over the past twenty years and currently constitutes an established area of research. This article aims at exploiting and organizing the knowledge accumulated in previous experimental studies to build a foundation for future sonification works. A systematic review of these studies may reveal trends in sonification design, and therefore support the development of design guidelines. To this end, we have reviewed and analyzed 179 scientific publications related to sonification of physical quantities. Using a bottom-up approach, we set up a list of conceptual dimensions belonging to both physical and auditory domains. Mappings used in the reviewed works were identified, forming a database of 495 entries. Frequency of use was analyzed among these conceptual dimensions as well as higher-level categories. Results confirm two hypotheses formulated in a preliminary study: pitch is by far the most used auditory dimension in sonification applications, and spatial auditory dimensions are almost exclusively used to sonify kinematic quantities. To detect successful as well as unsuccessful sonification strategies, assessment of mapping efficiency conducted in the reviewed works was considered. Results show that a proper evaluation of sonification mappings is performed only in a marginal proportion of publications. Additional aspects of the publication database were investigated: historical distribution of sonification works is presented, projects are classified according to their primary function, and the sonic material used in the auditory display is discussed. Finally, a mapping-based approach for characterizing sonification is proposed. PMID:24358192

Improved thermodynamics of the dense solar plasma and molecular-dynamics simulations of the nuclear-reaction rates

NASA Astrophysics Data System (ADS)

Mao, Dan

The conditions in the solar interior are so extreme that it has so far been impossible to match them in a laboratory. However, for nearly 50 years solar oscillations have been precisely observed, and the wealth of their data has enabled us to study the interior of the Sun as if it were a laboratory. Helioseismology is the name of this branch of astrophysics. It allows a high- precision diagnostic of the thermodynamic quantities in the solar interior. High-quality thermodynamic quantities are crucial for successful solar modeling. If good solar models are desired, considerable theoretical effort is required. Good solar models, in turn, are fundamental tools for solar physics. The most prominent example of this link between solar physics and basic physics was the resolution of the solar neutrino problem in 2002. The equation of state is a key material property that describes the relation between pressure, density and temperature. If the equation of state is derived from a thermodynamic potential it will also determine all associated thermodynamic quantities. A second key material property is the nuclear-energy production rate, which plays a crucial role in the solar core. Both are important physical properties describing the structure of the Sun. Both derive from microphysical models. In the equation-of-state part, we have studied two models of the equation of state (EOS). One is the MHD EOS, which is widely used in solar models. In our research, we have incorporated new terms into the MHD EOS. These terms have been borrowed from the major competing formalism, the OPAL EOS. They were missing in the original MHD EOS. Not only do the upgrades bring MHD closer to the OPAL equation of state, which is well known for its better match with observations. Most importantly it will allow solar modelers to use the OPAL equation of state directly, without recourse to the OPAL tables distributed by the Lawrence Livermore National Laboratory. Since the OPAL code is not publicly available, there is no alternative source. The official OPAL tables, however, have disadvantages. First, they are inflexible regarding the chemical mix, which is set once and for all by the producers of the tables. Our equation of state will allow the user to choose, in principle, an arbitrary mix. Second, the OPAL tables by their very nature are limited by the errors of interpolation within tables. The second equation of state model is a density expansion based on the Feynman-Kac path-integral formalism. By making use of the equivalence of quantum Hamiltonian matrix and the classical action of closed and open filaments (paths), an analytic formalism of equation of state. Although the character of density expansion limits its application, the formalism can still be valid in most region in the Sun. Our work provides the link between the abstract theoretical formalism that was developed in the 1990s and a numerically smooth realization that can be used in solar and stellar models. Since it is so far the most exact and systematic approach for an EOS, it provides another way to study the influence of different very fine physical effects, despite considerable limitations in its domain of applicability. In the nuclear-reaction part of the thesis, we have used a molecular-dynamics method to simulate the motion of protons in a hydrogen plasma (which is a good approximation for this purpose). Quantum tunneling explains why nuclear fusion can occur in the first place, considering the "low" temperature in the solar core. It is well known that this tunneling is enhanced (which leads to higher nuclear reaction rates) in the presence of Coulomb screening. In the 1950, Salpeter formulated a theory based on the static-screened Coulomb potential, as derived by Debye and H=FCckel in the 1920s. As expected, Salpeter obtained enhanced reaction rates. But from our simulation, we confirmed the results of a recent controversy about the existence of a dynamic effect. Since the bulk of fusion reactions happens at the high end of the Maxwell distribution, this is an relevant issue. Our work is the first independent confirmation of such a dynamic effect.

Effects of short read quality and quantity on a de novo vertebrate transcriptome assembly.

PubMed

Garcia, T I; Shen, Y; Catchen, J; Amores, A; Schartl, M; Postlethwait, J; Walter, R B

2012-01-01

For many researchers, next generation sequencing data holds the key to answering a category of questions previously unassailable. One of the important and challenging steps in achieving these goals is accurately assembling the massive quantity of short sequencing reads into full nucleic acid sequences. For research groups working with non-model or wild systems, short read assembly can pose a significant challenge due to the lack of pre-existing EST or genome reference libraries. While many publications describe the overall process of sequencing and assembly, few address the topic of how many and what types of reads are best for assembly. The goal of this project was use real world data to explore the effects of read quantity and short read quality scores on the resulting de novo assemblies. Using several samples of short reads of various sizes and qualities we produced many assemblies in an automated manner. We observe how the properties of read length, read quality, and read quantity affect the resulting assemblies and provide some general recommendations based on our real-world data set. Published by Elsevier Inc.

A renormalization group approach to identifying the local quantum numbers in a many-body localized system

NASA Astrophysics Data System (ADS)

Pekker, David; Clark, Bryan K.; Oganesyan, Vadim; Refael, Gil; Tian, Binbin

Many-body localization is a dynamical phase of matter that is characterized by the absence of thermalization. One of the key characteristics of many-body localized systems is the emergence of a large (possibly maximal) number of local integrals of motion (local quantum numbers) and corresponding conserved quantities. We formulate a robust algorithm for identifying these conserved quantities, based on Wegner's flow equations - a form of the renormalization group that works by disentangling the degrees of freedom of the system as opposed to integrating them out. We test our algorithm by explicit numerical comparison with more engineering based algorithms - Jacobi rotations and bi-partite matching. We find that the Wegner flow algorithm indeed produces the more local conserved quantities and is therefore more optimal. A preliminary analysis of the conserved quantities produced by the Wegner flow algorithm reveals the existence of at least two different localization lengthscales. Work was supported by AFOSR FA9550-10-1-0524 and FA9550-12-1-0057, the Kaufmann foundation, and SciDAC FG02-12ER46875.

Proactive management of fermentation and formulation interactions to improve biocontrol product performance

USDA-ARS?s Scientific Manuscript database

The key components of biocontrol product development; discovery, fermentation, and formulation, are interactively linked to each other and ultimately, to product performance. The fermentation environment can be managed to maximize the quantity and quality of biomass and bioproducts produced which, ...

Key Findings of AAP Store Survey

ERIC Educational Resources Information Center

Melendes, Bob; And Others

1977-01-01

Results of the Association of American Publishers "College Bookstore Marketing Survey" in the fall of 1976 are summarized. The intent was to improve college textbook publisher services to college stores in the areas of order fulfillment, publication scheduling, print quantities, shipping, billing, and processing of returns. (LBH)

SWEIS Yearbook-2012 Comparison of 2012 Data to Projections of the 2008 Site-Wide Environmental Impact Statement for Continued Operation of Los Alamos National Laboratory

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mahowald, Hallie B.; Wright, Marjorie Alys

2014-01-16

Los Alamos National Laboratory (LANL or the Laboratory) operations data for Calendar Year (CY) 2012 mostly fell within the 2008 Site-Wide Environmental Impact Statement (SWEIS) projections. Operation levels for one LANL facility exceeded the 2008 SWEIS capability projections—Radiochemistry Facility; however, none of the capability increases caused exceedances in radioactive air emissions, waste generation, or National Pollutant Discharge Elimination System (NPDES) discharge. Several facilities exceeded the2008 SWEIS levels for waste generation quantities; however, all were one-time, non-routine events that do not reflect the day-to-day operations of the Laboratory. In addition, total site-wide waste generation quantities were below SWEIS projections for allmore » waste types, reflecting the overall levels of operations at both the Key and Non-Key Facilities. Although gas and electricity consumption have remained within the 2008 SWEIS limits for utilities, water consumption exceeded the 2008 SWEIS projections by 27 million gallons in CY 2012.« less

Key comparison CCPR-K1.a as an interlaboratory comparison of correlated color temperature

NASA Astrophysics Data System (ADS)

Kärhä, P.; Vaskuri, A.; Pulli, T.; Ikonen, E.

2018-02-01

We analyze the results of spectral irradiance key comparison CCPR-K1.a for correlated color temperature (CCT). For four participants out of 13, the uncertainties of CCT, calculated using traditional methods, not accounting for correlations, would be too small. The reason for the failure of traditional uncertainty calculation is spectral correlations, producing systematic deviations of the same sign over certain wavelength regions. The results highlight the importance of accounting for such correlations when calculating uncertainties of spectrally integrated quantities.

On the Construction and Dynamics of Knotted Fields

NASA Astrophysics Data System (ADS)

Kedia, Hridesh

Representing a physical field in terms of its field lines has often enabled a deeper understanding of complex physical phenomena, from Faraday's law of magnetic induction, to the Helmholtz laws of vortex motion, to the free energy density of liquid crystals in terms of the distortions of the lines of the director field. At the same time, the application of ideas from topology--the study of properties that are invariant under continuous deformations--has led to robust insights into the nature of complex physical systems from defects in crystal structures, to the earth's magnetic field, to topological conservation laws. The study of knotted fields, physical fields in which the field lines encode knots, emerges naturally from the application of topological ideas to the investigation of the physical phenomena best understood in terms of the lines of a field. A knot--a closed loop tangled with itself which can not be untangled without cutting the loop--is the simplest topologically non-trivial object constructed from a line. Remarkably, knots in the vortex (magnetic field) lines of a dissipationless fluid (plasma), persist forever as they are transported by the flow, stretching and rotating as they evolve. Moreover, deeply entwined with the topology-preserving dynamics of dissipationless fluids and plasmas, is an additional conserved quantity--helicity, a measure of the average linking of the vortex (magnetic field) lines in a fluid (plasma)--which has had far-reaching consequences for fluids and plasmas. Inspired by the persistence of knots in dissipationless flows, and their far-reaching physical consequences, we seek to understand the interplay between the dynamics of a field and the topology of its field lines in a variety of systems. While it is easy to tie a knot in a shoelace, tying a knot in the the lines of a space-filling field requires contorting the lines everywhere to match the knotted region. The challenge of analytically constructing knotted field configurations has impeded a deeper understanding of the interplay between topology and dynamics in fluids and plasmas. We begin by analytically constructing knotted field configurations which encode a desired knot in the lines of the field, and show that their helicity can be tuned independently of the encoded knot. The nonlinear nature of the physical systems in which these knotted field configurations arise, makes their analytical study challenging. We ask if a linear theory such as electromagnetism can allow knotted field configurations to persist with time. We find analytical expressions for an infinite family of knotted solutions to Maxwell's equations in vacuum and elucidate their connections to dissipationless flows. We present a design rule for constructing such persistently knotted electromagnetic fields, which could possibly be used to transfer knottedness to matter such as quantum fluids and plasmas. An important consequence of the persistence of knots in classical dissipationless flows is the existence of an additional conserved quantity, helicity, which has had far-reaching implications. To understand the existence of analogous conserved quantities, we ask if superfluids, which flow without dissipation just like classical dissipationless flows, have an additional conserved quantity akin to helicity. We address this question using an analytical approach based on defining the particle relabeling symmetry--the symmetry underlying helicity conservation--in superfluids, and find that an analogous conserved quantity exists but vanishes identically owing to the intrinsic geometry of complex scalar fields. Furthermore, to address the question of a ``classical limit'' of superfluid vortices which recovers classical helicity conservation, we perform numerical simulations of \\emph{bundles} of superfluid vortices, and find behavior akin to classical viscous flows.

Lasers, Cold Atoms and Atomic Clocks: Realizing the Second Today

NASA Astrophysics Data System (ADS)

Calonico, Davide

2013-09-01

The time is the physical quantity that mankind could measure with the best accuracy, thanks to the properties of the atomic physics, as the present definition of time is based on atomic energy transitions. This short review gives some basic information on the heart of the measurement of time in the contemporary world, i.e. the atomic clocks, and some trends related.

Enhanced verification test suite for physics simulation codes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kamm, James R.; Brock, Jerry S.; Brandon, Scott T.

2008-09-01

This document discusses problems with which to augment, in quantity and in quality, the existing tri-laboratory suite of verification problems used by Los Alamos National Laboratory (LANL), Lawrence Livermore National Laboratory (LLNL), and Sandia National Laboratories (SNL). The purpose of verification analysis is demonstrate whether the numerical results of the discretization algorithms in physics and engineering simulation codes provide correct solutions of the corresponding continuum equations.

Finite coupling corrections to holographic predictions for hot QCD

DOE PAGES

Waeber, Sebastian; Schafer, Andreas; Vuorinen, Aleksi; ...

2015-11-13

Finite ’t Hooft coupling corrections to multiple physical observables in strongly coupled N=4 supersymmetric Yang-Mills plasma are examined, in an attempt to assess the stability of the expansion in inverse powers of the ’t Hooft coupling λ. Observables considered include thermodynamic quantities, transport coefficients, and quasinormal mode frequencies. Furthermore large λ expansions for quasinormal mode frequencies are notably less well behaved than the expansions of other quantities, we find that a partial resummation of higher order corrections can significantly reduce the sensitivity of the results to the value of λ.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Reyne, G.; Magnin, H.; Berliat, G.

A supervisor has been developed so as to allow successive 3D computations of different quantities by different softwares on the same physical problem. Noise of a given power oil transformer can be deduced from the surface vibrations of the tank. These vibrations are obtained through a mechanic computation whose Inputs are the electromagnetic forces provided . by an electromagnetic computation. Magnetic, mechanic and acoustic experimental data are compared with the results of the 3D computations. Stress Is put on the main characteristics of the supervisor such as the transfer of a given quantity from one mesh to the other.

Measurement model as a means for studying the process of emotion origination

NASA Astrophysics Data System (ADS)

Taymanov, R.; Baksheeva, Iu; Sapozhnikova, K.; Chunovkina, A.

2016-11-01

In the last edition of the International Vocabulary of Metrology the concept “measurement” was spread outside the field of physical quantities. This fact makes it relevant to analyze the experience of developing the models of multidimensional quantity measurements. The model of measurements of expected emotions caused by musical and other acoustic impacts, is considered. The model relies upon a hypothesis of a nonlinear conversion of acoustic signals to a neurophysiological reaction giving rise to emotion. Methods for checking this hypothesis as well as experimental results are given.

SENSITIVE PRESSURE GAUGE

DOEpatents

Ball, W.P.

1961-01-01

An electron multiplier device is described. It has a plurality of dynodes between an anode and cathode arranged to measure pressure, temperature, or other environmental physical conditions that proportionately iinfuences the quantity of gas molecules between the dynodes. The output current of the device is influenced by the reduction in electron multiplication at the dynodes due to energy reducing collisions of the electrons with the gas molecules between the dynodes. More particularly, the current is inversely proportional to the quantity of gas molecules, viz., the gas pressure. The device is, hence, extremely sensitive to low pressures.

Krein signature for instability of PT-symmetric states

NASA Astrophysics Data System (ADS)

Chernyavsky, Alexander; Pelinovsky, Dmitry E.

2018-05-01

Krein quantity is introduced for isolated neutrally stable eigenvalues associated with the stationary states in the PT-symmetric nonlinear Schrödinger equation. Krein quantity is real and nonzero for simple eigenvalues but it vanishes if two simple eigenvalues coalesce into a defective eigenvalue. A necessary condition for bifurcation of unstable eigenvalues from the defective eigenvalue is proved. This condition requires the two simple eigenvalues before the coalescence point to have opposite Krein signatures. The theory is illustrated with several numerical examples motivated by recent publications in physics literature.

Disruption mitigation by injection of small quantities of noble gas in ASDEX Upgrade

NASA Astrophysics Data System (ADS)

Pautasso, G.; Bernert, M.; Dibon, M.; Duval, B.; Dux, R.; Fable, E.; Fuchs, J. C.; Conway, G. D.; Giannone, L.; Gude, A.; Herrmann, A.; Hoelzl, M.; McCarthy, P. J.; Mlynek, A.; Maraschek, M.; Nardon, E.; Papp, G.; Potzel, S.; Rapson, C.; Sieglin, B.; Suttrop, W.; Treutterer, W.; The ASDEX Upgrade Team; The EUROfusion MST1 Team

2017-01-01

The most recent experiments of disruption mitigation by massive gas injection in ASDEX Upgrade have concentrated on small—relatively to the past—quantities of noble gas injected, and on the search for the minimum amount of gas necessary for the mitigation of the thermal loads on the divertor and for a significant reduction of the vertical force during the current quench. A scenario for the generation of a long-lived runaway electron beam has been established; this allows the study of runaway current dissipation by moderate quantities of argon injected. This paper presents these recent results and discusses them in the more general context of physical models and extrapolation, and of the open questions, relevant for the realization of the ITER disruption mitigation system.

Estimating the effect of fermentation yeast on distillers grains protein

USDA-ARS?s Scientific Manuscript database

Distillers dried grains with solubles (DDGS) is the key co-product of bio-ethanol production from grains. Major factors affecting its quality and market values include protein quantity (concentration) and quality (amino acid composition). Yet, the effect of fermentation yeast on DDGS quality has no...

Identifying Key Events in AOPs for Embryonic Disruption using Computational Toxicology (European Teratology Society - AOP symp.)

EPA Science Inventory

Addressing safety aspects of drugs and environmental chemicals relies extensively on animal testing; however, the quantity of chemicals needing assessment and challenges of species extrapolation require alternative approaches to traditional animal studies. Newer in vitro and in s...

Comparison of radar and gauge precipitation data in watershed models across varying spatial and temporal scales

EPA Science Inventory

Precipitation is a key control on watershed hydrologic modelling output, with errors in rainfall propagating through subsequent stages of water quantity and quality analysis. Most watershed models incorporate precipitation data from rain gauges; higher-resolution data sources are...

Robust shot-noise measurement for continuous-variable quantum key distribution

NASA Astrophysics Data System (ADS)

Kunz-Jacques, Sébastien; Jouguet, Paul

2015-02-01

We study a practical method to measure the shot noise in real time in continuous-variable quantum key distribution systems. The amount of secret key that can be extracted from the raw statistics depends strongly on this quantity since it affects in particular the computation of the excess noise (i.e., noise in excess of the shot noise) added by an eavesdropper on the quantum channel. Some powerful quantum hacking attacks relying on faking the estimated value of the shot noise to hide an intercept and resend strategy were proposed. Here, we provide experimental evidence that our method can defeat the saturation attack and the wavelength attack.

Entropy, a Unifying Concept: from Physics to Cognitive Psychology

NASA Astrophysics Data System (ADS)

Tsallis, Constantino; Tsallis, Alexandra C.

Together with classical, relativistic and quantum mechanics, as well as Maxwell electromagnetism, Boltzmann-Gibbs (BG) statistical mechanics constitutes one of the main theories of contemporary physics. This theory primarily concerns inanimate matter, and at its generic foundation we find nonlinear dynamical systems satisfying the ergodic hypothesis. This hypothesis is typically guaranteed for systems whose maximal Lyapunov exponent is positive. What happens when this crucial quantity is zero instead? We suggest here that, in what concerns thermostatistical properties, we typically enter what in some sense may be considered as a new world — the world of living systems — . The need emerges, at least for many systems, for generalizing the basis of BG statistical mechanics, namely the Boltzmann-Gibbs-von Neumann-Shannon en-tropic functional form, which connects the oscopic, thermodynamic quantity, with the occurrence probabilities of microscopic configurations. This unifying approach is briefly reviewed here, and its widespread applications — from physics to cognitive psychology — are overviewed. Special attention is dedicated to the learning/memorizing process in humans and computers. The present observations might be related to the gestalt theory of visual perceptions and the actor-network theory.

Application of the GA-BP Neural Network in Earthwork Calculation

NASA Astrophysics Data System (ADS)

Fang, Peng; Cai, Zhixiong; Zhang, Ping

2018-01-01

The calculation of earthwork quantity is the key factor to determine the project cost estimate and the optimization of the scheme. It is of great significance and function in the excavation of earth and rock works. We use optimization principle of GA-BP intelligent algorithm running process, and on the basis of earthwork quantity and cost information database, the design of the GA-BP neural network intelligent computing model, through the network training and learning, the accuracy of the results meet the actual engineering construction of gauge fan requirements, it provides a new approach for other projects the calculation, and has good popularization value.

Active Subspaces of Airfoil Shape Parameterizations

NASA Astrophysics Data System (ADS)

Grey, Zachary J.; Constantine, Paul G.

2018-05-01

Design and optimization benefit from understanding the dependence of a quantity of interest (e.g., a design objective or constraint function) on the design variables. A low-dimensional active subspace, when present, identifies important directions in the space of design variables; perturbing a design along the active subspace associated with a particular quantity of interest changes that quantity more, on average, than perturbing the design orthogonally to the active subspace. This low-dimensional structure provides insights that characterize the dependence of quantities of interest on design variables. Airfoil design in a transonic flow field with a parameterized geometry is a popular test problem for design methodologies. We examine two particular airfoil shape parameterizations, PARSEC and CST, and study the active subspaces present in two common design quantities of interest, transonic lift and drag coefficients, under each shape parameterization. We mathematically relate the two parameterizations with a common polynomial series. The active subspaces enable low-dimensional approximations of lift and drag that relate to physical airfoil properties. In particular, we obtain and interpret a two-dimensional approximation of both transonic lift and drag, and we show how these approximation inform a multi-objective design problem.

Noether and Abbott-Deser-Tekin conserved quantities in scalar-tensor theory of gravity both in Jordan and Einstein frames

NASA Astrophysics Data System (ADS)

Bhattacharya, Krishnakanta; Das, Ashmita; Majhi, Bibhas Ranjan

2018-06-01

We revisit the thermodynamic aspects of the scalar-tensor theory of gravity in the Jordan and in the Einstein frame. Examining the missing links of this theory carefully, we establish the thermodynamic descriptions from the conserved currents and potentials by following both the Noether and the Abbott-Deser-Tekin (ADT) formalism. With the help of conserved Noether current and potential, we define the thermodynamic quantities, which we show to be conformally invariant. Moreover, the defined quantities are shown to fit nicely in the laws of (the first and the second) black hole thermodynamics formulated by the Wald's method. We stretch the study of the conformal equivalence of the physical quantities in these two frames by following the ADT formalism. Our further study reveals that there is a connection between the ADT and the Noether conserved quantities, which signifies that the ADT approach provide the equivalent thermodynamic description in the two frames as obtained in Noether prescription. Our whole analysis is very general as the conserved Noether and ADT currents and potentials are formulated off-shell and the analysis is exempted from any prior assumption or boundary condition.

Calculating Coronal Mass Ejection Magnetic Field at 1 AU Using Solar Observables

NASA Astrophysics Data System (ADS)

Chen, J.; Kunkel, V.

2013-12-01

It is well-established that most major nonrecurrent geomagnetic storms are caused by solar wind structures with long durations of strong southward (Bz < 0) interplanetary magnetic field (IMF). Such geoeffective IMF structures are associated with CME events at the Sun. Unfortunately, neither the duration nor the internal magnetic field vector of the ejecta--the key determinants of geoeffectiveness--is measurable until the observer (e.g., Earth) passes through the ejecta. In this paper, we discuss the quantitative relationships between the ejecta magnetic field at 1 AU and remotely observable solar quantities associated with the eruption of a given CME. In particular, we show that observed CME trajectories (position-time data) within, say, 1/3 AU of the Sun, contain sufficient information to allow the calculation of the ejecta magnetic field (magnitude and components) at 1 AU using the Erupting Flux Rope (EFR) model of CMEs. Furthermore, in order to accurately determine the size and arrival time of the ejecta as seen by a fixed observer at 1 AU (e.g., ACE), it is essential to accurately calculate the three-dimensional geometry of the underlying magnetic structure. Accordingly, we have extended the physics-based EFR model to include a self-consistent calculation of the transverse expansion taking into account the non-symmetric drag coupling between an expanding CME flux rope and the ambient solar wind. The dependence of the minor radius of the flux rope at 1 AU that determines the perceived size of the ejecta on solar quantities is discussed. Work supported by the NRL Base Program.

Strain-based diffusion solver for realistic representation of diffusion front in physical reactions

PubMed Central

2017-01-01

When simulating fluids, such as water or fire, interacting with solids, it is a challenging problem to represent details of diffusion front in physical reaction. Previous approaches commonly use isotropic or anisotropic diffusion to model the transport of a quantity through a medium or long interface. We have identified unrealistic monotonous patterns with previous approaches and therefore, propose to extend these approaches by integrating the deformation of the material with the diffusion process. Specifically, stretching deformation represented by strain is incorporated in a divergence-constrained diffusion model. A novel diffusion model is introduced to increase the global rate at which the solid acquires relevant quantities, such as heat or saturation. This ensures that the equations describing fluid flow are linked to the change of solid geometry, and also satisfy the divergence-free condition. Experiments show that our method produces convincing results. PMID:28448591

A tensorial description of particle perception in black-hole physics

NASA Astrophysics Data System (ADS)

Barbado, Luis C.; Barceló, Carlos; Garay, Luis J.; Jannes, G.

2016-09-01

In quantum field theory in curved backgrounds, one typically distinguishes between objective, tensorial quantities such as the renormalized stress-energy tensor (RSET) and subjective, nontensorial quantities such as Bogoliubov coefficients which encode perception effects associated with the specific trajectory of a detector. In this work, we propose a way to treat both objective and subjective notions on an equal tensorial footing. For that purpose, we define a new tensor which we will call the perception renormalized stress-energy tensor (PeRSET). The PeRSET is defined as the subtraction of the RSET corresponding to two different vacuum states. Based on this tensor, we can define perceived energy densities and fluxes. The PeRSET helps us to have a more organized and systematic understanding of various results in the literature regarding quantum field theory in black hole spacetimes. We illustrate the physics encoded in this tensor by working out various examples of special relevance.

Universal I-Love-Q and Multipole-Love Relations

NASA Astrophysics Data System (ADS)

Yagi, Kent; Yunes, Nicolas

2014-03-01

One of largest uncertainties in nuclear physics is the equation of state (EoS) in nuclear and supra-nuclear densities. Neutron-star (NS) and quark-star (QS) observables such as the mass and radius depend strongly on the EoS. We find universal relations among the moment-of-inertia, quadrupole moment and various tidal deformabilities of a slowly-rotating NS and QS that are almost EoS-independent. Such unexpected relations have several interesting applications. On an observational astrophysical front, independent measurement of any two quantities automatically determines the others that are not easily accessible. On a gravitational-wave front, such relations allow us to break the degeneracy between the spins and quadrupole moment, or between various tidal deformabilities. On a fundamental physics front, any two independent measurements of the quantities allow for a model-independent and EoS-independent test of general relativity.

Robustness results in LQG based multivariable control designs

NASA Technical Reports Server (NTRS)

Lehtomaki, N. A.; Sandell, N. R., Jr.; Athans, M.

1980-01-01

The robustness of control systems with respect to model uncertainty is considered using simple frequency domain criteria. Results are derived under a common framework in which the minimum singular value of the return difference transfer matrix is the key quantity. In particular, the LQ and LQG robustness results are discussed.

Defense Planning for National Security: Navigation Aids for the Mystery Tour

DTIC Science & Technology

2014-03-01

to provide in the necessary quantity. 2. Training: superior training regimes are not en- tirely reliable as keys to victory. Although rigorous... eccentric misbehavior, the question of how much tolerance is permissible should not be ignored. The reason is not simply academic pedant- ry. A single

Enhancing Student Learning with Brain-Based Research

ERIC Educational Resources Information Center

Bonnema, Ted R.

2009-01-01

This paper discusses brain-based learning and its relation to classroom instruction. A rapidly growing quantity of research currently exists regarding how the brain perceives, processes, and ultimately learns new information. In order to maximize their teaching efficacy, educators should have a basic understanding of key memory functions in the…

Watching what widlife want and need

Treesearch

Natasha Vizcarra; Mary Rowland; Christina Vojta

2016-01-01

National forests and grasslands are home to a diverse array of wildlife. To keep tabs on the general viability and wellbeing of these inhabitants, land managers need practical, defensible monitoring protocols. Population monitoring is one method. Another is habitat monitoring, which provides critical information about the quantity and quality of key habitat attributes...

Cellulosic ethanol production from warm-season perennial grasses

USDA-ARS?s Scientific Manuscript database

Warm-season (C4) perennial grasses are able to produce large quantities of biomass, and will play a key role in bioenergy production, particularly in areas with long warm growing seasons. Several different grass species have been studied as candidate bioenergy crops for the Southeast USA, and each ...

A novel algorithm for the calculation of physical and biological irradiation quantities in scanned ion beam therapy: the beamlet superposition approach

NASA Astrophysics Data System (ADS)

Russo, G.; Attili, A.; Battistoni, G.; Bertrand, D.; Bourhaleb, F.; Cappucci, F.; Ciocca, M.; Mairani, A.; Milian, F. M.; Molinelli, S.; Morone, M. C.; Muraro, S.; Orts, T.; Patera, V.; Sala, P.; Schmitt, E.; Vivaldo, G.; Marchetto, F.

2016-01-01

The calculation algorithm of a modern treatment planning system for ion-beam radiotherapy should ideally be able to deal with different ion species (e.g. protons and carbon ions), to provide relative biological effectiveness (RBE) evaluations and to describe different beam lines. In this work we propose a new approach for ion irradiation outcomes computations, the beamlet superposition (BS) model, which satisfies these requirements. This model applies and extends the concepts of previous fluence-weighted pencil-beam algorithms to quantities of radiobiological interest other than dose, i.e. RBE- and LET-related quantities. It describes an ion beam through a beam-line specific, weighted superposition of universal beamlets. The universal physical and radiobiological irradiation effect of the beamlets on a representative set of water-like tissues is evaluated once, coupling the per-track information derived from FLUKA Monte Carlo simulations with the radiobiological effectiveness provided by the microdosimetric kinetic model and the local effect model. Thanks to an extension of the superposition concept, the beamlet irradiation action superposition is applicable for the evaluation of dose, RBE and LET distributions. The weight function for the beamlets superposition is derived from the beam phase space density at the patient entrance. A general beam model commissioning procedure is proposed, which has successfully been tested on the CNAO beam line. The BS model provides the evaluation of different irradiation quantities for different ions, the adaptability permitted by weight functions and the evaluation speed of analitical approaches. Benchmarking plans in simple geometries and clinical plans are shown to demonstrate the model capabilities.

Quality of diet plans for weight loss featured in women's magazines. A cross-sectional descriptive study.

PubMed

Martinighi, Maiara; Koga da Silva, Edina Mariko

2017-01-01

Brazil has the fifth largest population of obese individuals in the world. Women's magazines publish a large number of diet plans, and therefore the objective of this study was to assess the quality of these plans. Cross-sectional descriptive study. We included the Brazilian women's magazines of highest circulation published between January and June 2014 that advertised diets for weight loss on their covers. We extracted the quantities of macro and micronutrients from each of these diet plans and compared these quantities with the World Health Organization nutritional guidelines for adult women. We also checked the total energy quantities of these plans, and any recommendations about water intake and physical activity. We identified 136 potentially eligible magazine issues; 41 were excluded and 95 issues of 6 different magazines were included in the study. We found that 83.1 % of the plans had carbohydrate and fiber levels below the recommendations. On the other hand, the protein and saturated fatty acid levels were above the recommendations in 97.8% and 95.7% of the plans, respectively; 75.7% of the diets had inadequate calcium levels and 70.5% had low iron levels. Only 30 plans specified the total daily quantity of dietary energy and in 53.3% of these, the information was inconsistent with our estimates; 20% of the plans had no recommendations on daily water intake and 37.5% did not give recommendations regarding physical activity practices. The diet plans for weight loss featured in Brazilian women's magazines are of low quality.

Associations between physical activity and sedentary behavior with sleep quality and quantity in young adults.

PubMed

Kakinami, Lisa; O'Loughlin, Erin K; Brunet, Jennifer; Dugas, Erika N; Constantin, Evelyn; Sabiston, Catherine M; O'Loughlin, Jennifer

2017-02-01

Intensity and duration of physical activity (PA) and sedentary behavior are individually associated with sleep, but their independent associations are poorly characterized. The objectives of this study were to determine if PA and/or sedentary behavior are/is associated with sleep quality and/or quantity in a young adult sample. Cross-sectional. Montreal, Canada. Participants (n=658) from the Nicotine Dependence in Teens Study. PA measures included total minutes of light, moderate, and vigorous PA in the past week; sedentary measures included number of hours per day watching television (TV) and using the computer for leisure activities in the past week. Sleep measures included (1) the Pittsburgh Sleep Quality Index, which assesses sleep quality in the past month, and (2) number of hours of sleep per night in the past month. Data were analyzed using multiple logistic regression adjusting for age, sex, and mother's education. In multivariable analyses, each additional hour of TV and computer use per day was associated with a 17% and 13% increase, respectively, in the odds of reporting poor sleep quality. After additionally adjusting for PA, the association between TV use and poor sleep quality remained significant (odds ratio: 1.15, 95% confidence interval: 1.01-1.28). Sedentary behavior was not associated with sleep quantity. PA intensity and duration were not associated with sleep quality or quantity. More time spent doing sedentary activities was associated with poorer sleep quality, but PA was not associated. Clinicians treating young adults with sleep problems should inquire about sedentary behavior. Copyright © 2016 National Sleep Foundation. Published by Elsevier Inc. All rights reserved.

Physically Active Adults: An Analysis of the Key Variables That Keep Them Moving

ERIC Educational Resources Information Center

Downs, Andrew

2016-01-01

Background: A large proportion of adults are insufficiently physically active, and researchers have yet to determine the factors that enable individuals to maintain adequate levels of physical activity throughout adulthood. Purpose: This study sought to identify the key variables linked with consistent physical activity in adulthood as elucidated…

Youth Physical Fitness: Ten Key Concepts

ERIC Educational Resources Information Center

Corbin, Charles B.; Welk, Gregory J.; Richardson, Cheryl; Vowell, Catherine; Lambdin, Dolly; Wikgren, Scott

2014-01-01

The promotion of physical fitness has been a key objective of physical education for more than a century. During this period, physical education has evolved to accommodate changing views on fitness and health. The purpose of this article is to discuss issues with fitness assessment and fitness education central to the new Presidential Youth…

Elementary Kaluza-Klein towers revisited

DOE Office of Scientific and Technical Information (OSTI.GOV)

Grard, Fernand; Nuyts, Jean

2006-12-15

Considering that the momentum squared in the extra dimensions is the physically relevant quantity for the generation of the Kaluza-Klein mass states, we have reanalyzed mathematically the procedure for five dimensional scalar fields within the Arkhani-Ahmed, Dimopoulos and Dvali scenario. We find new sets of physically allowed boundary conditions. Beside the usual results, they lead to new towers with non regular mass spacing, to lonely mass states and to tachyons.

Range determination for scannerless imaging

DOEpatents

Muguira, Maritza Rosa; Sackos, John Theodore; Bradley, Bart Davis; Nellums, Robert

2000-01-01

A new method of operating a scannerless range imaging system (e.g., a scannerless laser radar) has been developed. This method is designed to compensate for nonlinear effects which appear in many real-world components. The system operates by determining the phase shift of the laser modulation, which is a physical quantity related physically to the path length between the laser source and the detector, for each pixel of an image.

Brokering and Bridging Knowledge in Health and Physical Education: A Critical Discourse Analysis of One External Provider's Curriculum

ERIC Educational Resources Information Center

Sperka, Leigh; Enright, Eimear; McCuaig, Louise

2018-01-01

Background: There has been a proliferation of external agencies 'knocking on the door' of, and being welcomed into, Health and Physical Education (HPE). This opens HPE up to new products, partners, and services. Although scholarship on the practice of outsourcing HPE is steadily growing in quantity and in scope, there is a significant gap in the…

Physical activity to overcome the adversity of widowhood: Benefits beyond physical health.

PubMed

Li, Chu-Shiu; Lee, June Han; Chang, Ly-Yun; Liu, Chwen-Chi; Chan, Yan-Lan; Wen, Christopher; Chiu, Mu-Lin; Tsai, Min Kuang; Tsai, Shan Pou; Wai, Jackson Pui Man; Tsao, Chwen Keng; Wu, Xifeng; Wen, Chi Pang

2016-08-01

Widowhood has been increasingly encountered because of increasing longevity of women, often characterized by social stigmatization and poor physical and mental health. However, applied research to overcome its adversity has been quite limited. The goal of this study is to explore the role of physical activity in improving the health of widows.A cohort of 446,582 adults in Taiwan who successively participated in a comprehensive medical screening program starting in 1994, including 232,788 women, was followed up for mortality until 2008. Each individual provided detailed health history, and extensive lab tests results.The number of widows increased with time trend. Every other woman above age 65 was a widow (44%). Widows were less active, more obese, and smoked and drank more, had sleep problems, were more depressed with taking sedatives or psychoactive drugs, leading to more suicides. In the global development of health policies by World Health Organization (WHO), physical activity is one of the main factors to reverse poor health. The poor health of inactive widow was mitigated when becoming fully active in this study. Exercise not only reduced the observed 18% increase in all-cause mortality, but also gained 4 years and as much as 14% mortality advantage over the married but inactive. More importantly, becoming physically active energized their mental status, improved sleep quality and quantity, reduced depressions and the need for psychoactive drugs, and increased socialization circles.Widows, a rapidly growing and socially stigmatized group, suffered from social and financial inequality and tended to develop poorer health. Sustained physical activity could be one of the ways for them to overcome and reverse some of the physical and mental adversities of widowhood, and improve their quality and quantity of life.

Eating habits and physical activity of adolescents in Katowice--the teenagers' declarations vs. their parents' beliefs.

PubMed

Bąk-Sosnowska, Monika; Skrzypulec-Plinta, Violetta

2012-09-01

To analyse eating and physical activity preferences among adolescent school children and to compare the teenagers' lifestyle declarations with their parents' beliefs. Unfavorable behavior in eating habits and physical activity may result in serious dysfunctions and diseases, such as eating disorders and incorrect body mass. A retrospective cross-sectional study conducted in 2010-2011. The data was collated from 711 pupils and 266 parents. The survey included questions on: breakfast consumption, types of food eaten for breakfast, time of supper, the daily number of meals, the quantity of fruit and vegetables, food products purchased in the school shop, as well as the type and level of physical activity. In the population of children aged 14-15 years, 10% do not eat 1st breakfast and 15% do not eat 2nd breakfast, 50% eat dairy products for 1st breakfast, 70% have sandwiches for 2nd breakfast, 45% most frequently buy snacks in the school shop, 65% prefer physical activity in the form of team games, and 90% willingly participate in PE classes. The parents' beliefs differ from their children's declarations with regard to: breakfast consumption, the number of meals a day, the quantity of fruit, and participation in PE classes. The lifestyle of the studied adolescents is within the norms recommended for their age group, although there is a tendency to skip breakfast. A positive aspect is the adolescents' engagement in physical activity. Parents underestimate their children's level of physical activity and overestimate their daily number of meals. The study confirms the validity of conducting health education, addressed to both children and their parents, with regard to correct eating habits and physical activity, as well as prevention of eating disorders. © 2012 Blackwell Publishing Ltd.

Physics and Chemistry of Star and Planet Formation in the Alma ERA

NASA Astrophysics Data System (ADS)

Bergin, Edwin

2014-06-01

ALMA will open up new avenues of exploration encompassing the wide range of star formation in our galaxy and peering into the central heart of planet-forming circumstellar disks. As we seek to explore the origins of stars and planets molecular emission will be at the front and center of many studies probing gas physics and chemistry. In this talk I will discus some of the areas where we can expect significant advances due to the increased sensitivity and superb spatial resolution of ALMA. In star-forming cores, a rich chemistry is revealed that may be the simpler molecular precursors to more complex organics, such as amino acids, seen within primitive rocks in our own solar system. ALMA will provide new information regarding the relative spatial distribution within a given source for a host of organics, sampling tens to hundreds of transitions of a variety of molecules, including presumably new ones. In this area there is a rich synergy with existing ground and space-based data, including Herschel/Spitzer. Here the increased sampling of sources to be enabled by ALMA should bring greater clarity toward the key products of interstellar chemistry and further constrain processes. On smaller Solar System scales, for over a decade most observations of planet-forming disks focused on the dust thermal continuum emission as a probe of the gas content and structure. ALMA will enable reliable and direct studies of gas to explore the evolving physics of planet-formation, the gas dissipation timescales (i.e. the upper limit to the timescale for giant planet birth), and also the chemistry. It is this chemistry that sets the composition of gas giants and also influences the ultimate composition of water and organic materials that are delivered to terrestrial worlds. Here I will show how we can use molecular emission to determine the gas thermal structure of a disk system and the total gas content - key astrophysical quantities. This will also enable more constrained chemical studies that will seek to determine whether the chemistry of planetary birth is universal and similar to our own.

Biochemical analysis of force-sensitive responses using a large-scale cell stretch device.

PubMed

Renner, Derrick J; Ewald, Makena L; Kim, Timothy; Yamada, Soichiro

2017-09-03

Physical force has emerged as a key regulator of tissue homeostasis, and plays an important role in embryogenesis, tissue regeneration, and disease progression. Currently, the details of protein interactions under elevated physical stress are largely missing, therefore, preventing the fundamental, molecular understanding of mechano-transduction. This is in part due to the difficulty isolating large quantities of cell lysates exposed to force-bearing conditions for biochemical analysis. We designed a simple, easy-to-fabricate, large-scale cell stretch device for the analysis of force-sensitive cell responses. Using proximal biotinylation (BioID) analysis or phospho-specific antibodies, we detected force-sensitive biochemical changes in cells exposed to prolonged cyclic substrate stretch. For example, using promiscuous biotin ligase BirA* tagged α-catenin, the biotinylation of myosin IIA increased with stretch, suggesting the close proximity of myosin IIA to α-catenin under a force bearing condition. Furthermore, using phospho-specific antibodies, Akt phosphorylation was reduced upon stretch while Src phosphorylation was unchanged. Interestingly, phosphorylation of GSK3β, a downstream effector of Akt pathway, was also reduced with stretch, while the phosphorylation of other Akt effectors was unchanged. These data suggest that the Akt-GSK3β pathway is force-sensitive. This simple cell stretch device enables biochemical analysis of force-sensitive responses and has potential to uncover molecules underlying mechano-transduction.

Trilogy, a Planetary Geodesy Mission Concept for Measuring the Expansion of the Solar System.

PubMed

Smith, David E; Zuber, Maria T; Mazarico, Erwan; Genova, Antonio; Neumann, Gregory A; Sun, Xiaoli; Torrence, Mark H; Mao, Dan-Dan

2018-04-01

The scale of the solar system is slowly changing, likely increasing as a result of solar mass loss, with additional change possible if there is a secular variation of the gravitational constant, G . The measurement of the change of scale could provide insight into the past and the future of the solar system, and in addition a better understanding of planetary motion and fundamental physics. Estimates for the expansion of the scale of the solar system are of order 1.5 cm year -1 AU -1 , which over several years is an observable quantity with present-day laser ranging systems. This estimate suggests that laser measurements between planets could provide an accurate estimate of the solar system expansion rate. We examine distance measurements between three bodies in the inner solar system -- Earth's Moon, Mars and Venus -- and outline a mission concept for making the measurements. The concept involves placing spacecraft that carry laser ranging transponders in orbit around each body and measuring the distances between the three spacecraft over a period of several years. The analysis of these range measurements would allow the co-estimation of the spacecraft orbit, planetary ephemerides, other geophysical parameters related to the constitution and dynamics of the central bodies, and key geodetic parameters related to the solar system expansion, the Sun, and theoretical physics.

Multifractal Characteristics of Axisymmetric Jet Turbulence Intensity from Rans Numerical Simulation

NASA Astrophysics Data System (ADS)

Seo, Yongwon; Ko, Haeng Sik; Son, Sangyoung

A turbulent jet bears diverse physical characteristics that have been unveiled yet. Of particular interest is to analyze the turbulent intensity, which has been a key factor to assess and determine turbulent jet performance since diffusive and mixing conditions are largely dependent on it. Multifractal measures are useful in terms of identifying characteristics of a physical quantity distributed over a spatial domain. This study examines the multifractal exponents of jet turbulence intensities obtained through numerical simulation. We acquired the turbulence intensities from numerical jet discharge experiments, where two types of nozzle geometry were tested based on a Reynolds-Averaged Navier-Stokes (RANS) equations. The k-𝜀 model and k-ω model were used for turbulence closure models. The results showed that the RANS model successfully regenerates transversal velocity profile, which is almost identical to an analytical solution. The RANS model also shows the decay of turbulence intensity in the longitudinal direction but it depends on the outfall nozzle lengths. The result indicates the existence of a common multifractal spectrum for turbulence intensity obtained from numerical simulation. Although the transverse velocity profiles are similar for two different turbulence models, the minimum Lipschitz-Hölder exponent (αmin) and entropy dimension (α1) are different. These results suggest that the multifractal exponents capture the difference in turbulence structures of hierarchical turbulence intensities produced by different turbulence models.

Trilogy, a planetary geodesy mission concept for measuring the expansion of the solar system

NASA Astrophysics Data System (ADS)

Smith, David E.; Zuber, Maria T.; Mazarico, Erwan; Genova, Antonio; Neumann, Gregory A.; Sun, Xiaoli; Torrence, Mark H.; Mao, Dan-dan

2018-04-01

The scale of the solar system is slowly changing, likely increasing as a result of solar mass loss, with additional change possible if there is a secular variation of the gravitational constant, G. The measurement of the change of scale could provide insight into the past and the future of the solar system, and in addition a better understanding of planetary motion and fundamental physics. Estimates for the expansion of the scale of the solar system are of order 1.5 cm year-1 AU-1, which over several years is an observable quantity with present-day laser ranging systems. This estimate suggests that laser measurements between planets could provide an accurate estimate of the solar system expansion rate. We examine distance measurements between three bodies in the inner solar system - Earth's Moon, Mars and Venus - and outline a mission concept for making the measurements. The concept involves placing spacecraft that carry laser ranging transponders in orbit around each body and measuring the distances between the three spacecraft over a period of several years. The analysis of these range measurements would allow the co-estimation of the spacecraft orbit, planetary ephemerides, other geophysical parameters related to the constitution and dynamics of the central bodies, and key geodetic parameters related to the solar system expansion, the Sun, and theoretical physics.

Among-species differences in pollen quality and quantity limitation: implications for endemics in biodiverse hotspots.

PubMed

Alonso, Conchita; Navarro-Fernández, Carmen M; Arceo-Gómez, Gerardo; Meindl, George A; Parra-Tabla, Víctor; Ashman, Tia-Lynn

2013-11-01

Insufficient pollination is a function of quantity and quality of pollen receipt, and the relative contribution of each to pollen limitation may vary with intrinsic plant traits and extrinsic ecological properties. Community-level studies are essential to evaluate variation across species in quality limitation under common ecological conditions. This study examined whether endemic species are more limited by pollen quantity or quality than non-endemic co-flowering species in three endemic-rich plant communities located in biodiversity hotspots of different continents (Andalusia, California and Yucatan). Natural variations in pollen receipt and pollen tube formation were analysed for 20 insect-pollinated plants. Endemic and non-endemic species that co-flowered were paired in order to estimate and compare the quantity and quality components of pre-zygotic pollination success, obtained through piecewise regression analysis of the relationship between pollen grains and pollen tubes of naturally pollinated wilted flowers. Pollen tubes did not frequently exceed the number of ovules per flower. Only the combination of abundant and good quality pollen and a low number of ovules per flower conferred relief from pre-zygotic pollen limitation in the three stochastic pollination environments studied. Quality of pollen receipt was found to be as variable as quantity among study species. The relative pollination success of endemic and non-endemic species, and its quantity and quality components, was community dependent. Assessing both quality and quantity of pollen receipt is key to determining the ovule fertilization potential of both endemic and widespread plants in biodiverse hotspot regions. Large natural variation among flowers of the same species in the two components and pollen tube formation deserves further analysis in order to estimate the environmental, phenotypic and intraindividual sources of variation that may affect how plants evolve to overcome this limitation in different communities worldwide.

Introduction to hydrology

USDA-ARS?s Scientific Manuscript database

Hydrology deals with the occurrence, movement, and storage of water in the Earth system. Hydrologic science comprises understanding the underlying physical and stochastic processes involved and estimating the quantity and quality of water in the various phases and stores. The study of hydrology als...

21 CFR 172.510 - Natural flavoring substances and natural substances used in conjunction with flavors.

Code of Federal Regulations, 2011 CFR

2011-04-01

... following conditions. (a) They are used in the minimum quantity required to produce their intended physical..., and other lichens Finished food thujone free 1 Olibanum Boswellia carteri Birdw. and other Boswellia...

21 CFR 172.510 - Natural flavoring substances and natural substances used in conjunction with flavors.

Code of Federal Regulations, 2010 CFR

2010-04-01

... conditions. (a) They are used in the minimum quantity required to produce their intended physical or..., and other lichens Finished food thujone free 1 Olibanum Boswellia carteri Birdw. and other Boswellia...

TECHNICAL ASPECTS OF UNDERGROUND STORAGE TANK CLOSURE

EPA Science Inventory

The overall objective of the study was to develop a deeper understanding of UST residuals at closure: their quantities, origins, physical/chemical properties, ease of removal by various cleaning methods, and their environmental mobility and persistence. The investigation covered ...

Producing Quality Water for Industrial Use.

ERIC Educational Resources Information Center

Schaezler, Donald J.

1978-01-01

This article discusses the quality of water demanded by industrial plants and the techniques which are currently employed to achieve them. Both quality and quantity requirements are considered including total plant operation, physical and chemical operating controls, and systems monitoring. (CS)

Effects of plant density on recombinant hemagglutinin yields in an Agrobacterium-mediated transient gene expression system using Nicotiana benthamiana plants.

PubMed

Fujiuchi, Naomichi; Matsuda, Ryo; Matoba, Nobuyuki; Fujiwara, Kazuhiro

2017-08-01

Agrobacterium-mediated transient expression systems enable plants to rapidly produce a wide range of recombinant proteins. To achieve economically feasible upstream production and downstream processing, it is beneficial to obtain high levels of two yield-related quantities of upstream production: recombinant protein content per fresh mass of harvested biomass (g gFM -1 ) and recombinant protein productivity per unit area-time (g m -2 /month). Here, we report that the density of Nicotiana benthamiana plants during upstream production had significant impacts on the yield-related quantities of recombinant hemagglutinin (HA). The two quantities were smaller at a high plant density of 400 plants m -2 than at a low plant density of 100 plants m -2 . The smaller quantities at the high plant density were attributed to: (i) a lower HA content in young leaves, which usually have high HA accumulation potentials; (ii) a lower biomass allocation to the young leaves; and (iii) a high area-time requirement for plants. Thus, plant density is a key factor for improving upstream production in Agrobacterium-mediated transient expression systems. Biotechnol. Bioeng. 2017;114: 1762-1770. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Cost-Effectiveness of Interventions to Promote Physical Activity: A Modelling Study

PubMed Central

Cobiac, Linda J.; Vos, Theo; Barendregt, Jan J.

2009-01-01

Background Physical inactivity is a key risk factor for chronic disease, but a growing number of people are not achieving the recommended levels of physical activity necessary for good health. Australians are no exception; despite Australia's image as a sporting nation, with success at the elite level, the majority of Australians do not get enough physical activity. There are many options for intervention, from individually tailored advice, such as counselling from a general practitioner, to population-wide approaches, such as mass media campaigns, but the most cost-effective mix of interventions is unknown. In this study we evaluate the cost-effectiveness of interventions to promote physical activity. Methods and Findings From evidence of intervention efficacy in the physical activity literature and evaluation of the health sector costs of intervention and disease treatment, we model the cost impacts and health outcomes of six physical activity interventions, over the lifetime of the Australian population. We then determine cost-effectiveness of each intervention against current practice for physical activity intervention in Australia and derive the optimal pathway for implementation. Based on current evidence of intervention effectiveness, the intervention programs that encourage use of pedometers (Dominant) and mass media-based community campaigns (Dominant) are the most cost-effective strategies to implement and are very likely to be cost-saving. The internet-based intervention program (AUS$3,000/DALY), the GP physical activity prescription program (AUS$12,000/DALY), and the program to encourage more active transport (AUS$20,000/DALY), although less likely to be cost-saving, have a high probability of being under a AUS$50,000 per DALY threshold. GP referral to an exercise physiologist (AUS$79,000/DALY) is the least cost-effective option if high time and travel costs for patients in screening and consulting an exercise physiologist are considered. Conclusions Intervention to promote physical activity is recommended as a public health measure. Despite substantial variability in the quantity and quality of evidence on intervention effectiveness, and uncertainty about the long-term sustainability of behavioural changes, it is highly likely that as a package, all six interventions could lead to substantial improvement in population health at a cost saving to the health sector. Please see later in the article for Editors' Summary PMID:19597537

Digital Model of Fourier and Fresnel Quantized Holograms

NASA Astrophysics Data System (ADS)

Boriskevich, Anatoly A.; Erokhovets, Valery K.; Tkachenko, Vadim V.

Some models schemes of Fourier and Fresnel quantized protective holograms with visual effects are suggested. The condition to arrive at optimum relationship between the quality of reconstructed images, and the coefficient of data reduction about a hologram, and quantity of iterations in the reconstructing hologram process has been estimated through computer model. Higher protection level is achieved by means of greater number both bi-dimensional secret keys (more than 2128) in form of pseudorandom amplitude and phase encoding matrixes, and one-dimensional encoding key parameters for every image of single-layer or superimposed holograms.

Kinematics, influence functions and field quantities for disturbance propagation from moving disturbance sources

NASA Technical Reports Server (NTRS)

Das, A.

1984-01-01

A unified method is presented for deriving the influence functions of moving singularities which determine the field quantities in aerodynamics and aeroacoustics. The moving singularities comprise volume and surface distributions having arbitrary orientations in space and to the trajectory. Hence one generally valid formula for the influence functions which reveal some universal relationships and remarkable properties in the disturbance fields. The derivations used are completely consistent with the physical processes in the propagation field, such that treatment renders new descriptions for some standard concepts. The treatment is uniformly valid for subsonic and supersonic Mach numbers.

Zone clearance in an infinite TASEP with a step initial condition

NASA Astrophysics Data System (ADS)

Cividini, Julien; Appert-Rolland, Cécile

2017-06-01

The TASEP is a paradigmatic model of out-of-equilibrium statistical physics, for which many quantities have been computed, either exactly or by approximate methods. In this work we study two new kinds of observables that have some relevance in biological or traffic models. They represent the probability for a given clearance zone of the lattice to be empty (for the first time) at a given time, starting from a step density profile. Exact expressions are obtained for single-time quantities, while more involved history-dependent observables are studied by Monte Carlo simulation, and partially predicted by a phenomenological approach.

Mixed boundary value problems in mechanics

NASA Technical Reports Server (NTRS)

Erdogan, F.

1975-01-01

Certain boundary value problems were studied over a domain D which may contain the point at infinity and may be multiply connected. Contours forming the boundary are assumed to consist of piecewise smooth arcs. Mixed boundary value problems are those with points of flux singularity on the boundary; these are points on the surface, either side of which at least one of the differential operator has different behavior. The physical system was considered to be described by two quantities, the potential and the flux type quantities. Some of the examples that were illustrated included problems in potential theory and elasticity.

Cosmic vacuum and galaxy formation

NASA Astrophysics Data System (ADS)

Chernin, A. D.

2006-04-01

It is demonstrated that the protogalactic perturbations must enter the nonlinear regime before the red shift z≈ 1; otherwise they would be destroyed by the antigravity of the vacuum dark energy at the subsequent epoch of the vacuum domination. At the zrrV={M/[(8π/3)ρV]}1/3, where M is the mass of a given over-density and ρV is the vacuum density. The criterion provides a new relation between the largest mass condensations and their spatial scales. All the real large-scale systems follow this relation definitely. It is also shown that a simple formula is possible for the key quantity in the theory of galaxy formation, namely the initial amplitude of the perturbation of the gravitational potential in the protogalactic structures. The amplitude is time independent and given in terms of the Friedmann integrals, which are genuine physical characteristics of the cosmic energies. The results suggest that there is a strong correspondence between the global design of the Universe as a whole and the cosmic structures of various masses and spatial scales.

A Unified Approach to the Thermodynamics and Quantum Scaling Functions of One-Dimensional Strongly Attractive SU(w) Fermi Gases

NASA Astrophysics Data System (ADS)

Yu, Yi-Cong; Guan, Xi-Wen

2017-06-01

We present a unified derivation of the pressure equation of states, thermodynamics and scaling functions for the one-dimensional (1D) strongly attractive Fermi gases with SU(w) symmetry. These physical quantities provide a rigorous understanding on a universality class of quantum criticality characterized by the critical exponents z = 2 and correlation length exponent ν = 1/2. Such a universality class of quantum criticality can occur when the Fermi sea of one branch of charge bound states starts to fill or becomes gapped at zero temperature. The quantum critical cone can be determined by the double peaks in specific heat, which serve to mark two crossover temperatures fanning out from the critical point. Our method opens to further study on quantum phases and phase transitions in strongly interacting fermions with large SU(w) and non-SU(w) symmetries in one dimension. Supported by the National Natural Science Foundation of China under Grant No 11374331 and the key NSFC under Grant No 11534014. XWG has been partially supported by the Australian Research Council.

Local models of astrophysical discs

NASA Astrophysics Data System (ADS)

Latter, Henrik N.; Papaloizou, John

2017-12-01

Local models of gaseous accretion discs have been successfully employed for decades to describe an assortment of small-scale phenomena, from instabilities and turbulence, to dust dynamics and planet formation. For the most part, they have been derived in a physically motivated but essentially ad hoc fashion, with some of the mathematical assumptions never made explicit nor checked for consistency. This approach is susceptible to error, and it is easy to derive local models that support spurious instabilities or fail to conserve key quantities. In this paper we present rigorous derivations, based on an asympototic ordering, and formulate a hierarchy of local models (incompressible, Boussinesq and compressible), making clear which is best suited for a particular flow or phenomenon, while spelling out explicitly the assumptions and approximations of each. We also discuss the merits of the anelastic approximation, emphasizing that anelastic systems struggle to conserve energy unless strong restrictions are imposed on the flow. The problems encountered by the anelastic approximation are exacerbated by the disc's differential rotation, but also attend non-rotating systems such as stellar interiors. We conclude with a defence of local models and their continued utility in astrophysical research.

Smart Health - Potential and Pathways: A Survey

NASA Astrophysics Data System (ADS)

Arulananthan, C.; Hanifa, Sabibullah Mohamed

2017-08-01

Healthcare is an imperative key field of research, where individuals or groups can be engaged in the self-tracking of any kind of biological, physical, behavioral, or environmental information. In a massive health care data, the valuable information is hidden. The quantity of the available unstructured data has been expanding on an exponential scale. The newly developing Disruptive Technologies can handle many challenges that face data analysis and ability to extract valuable information via data analytics. Connected Wellness in Healthcare would retrieve patient’s physiological, pathological and behavioral parameters through sensors to perform inner workings of human body analysis. Disruptive technologies can take us from a reactive illness-driven to a proactive wellness-driven system in health care. It is need to be strive and create a smart health system towards wellness-driven instead of being illness-driven, today’s biggest problem in health care. Wellness-driven-analytics application help to promote healthiest living environment called “Smart Health”, deliver empower based quality of living. The contributions of this survey reveals and opens (touches uncovered areas) the possible doors in the line of research on smart health and its computing technologies.

A square-force cohesion model and its extraction from bulk measurements

NASA Astrophysics Data System (ADS)

Liu, Peiyuan; Lamarche, Casey; Kellogg, Kevin; Hrenya, Christine

2017-11-01

Cohesive particles remain poorly understood, with order of magnitude differences exhibited for prior, physical predictions of agglomerate size. A major obstacle lies in the absence of robust models of particle-particle cohesion, thereby precluding accurate prediction of the behavior of cohesive particles. Rigorous cohesion models commonly contain parameters related to surface roughness, to which cohesion shows extreme sensitivity. However, both roughness measurement and its distillation into these model parameters are challenging. Accordingly, we propose a ``square-force'' model, where cohesive force remains constant until a cut-off separation. Via DEM simulations, we demonstrate validity of the square-force model as surrogate of more rigorous models, when its two parameters are selected to match the two key quantities governing dense and dilute granular flows, namely maximum cohesive force and critical cohesive energy, respectively. Perhaps more importantly, we establish a method to extract the parameters in the square-force model via defluidization, due to its ability to isolate the effects of the two parameters. Thus, instead of relying on complicated scans of individual grains, determination of particle-particle cohesion from simple bulk measurements becomes feasible. Dow Corning Corporation.

Statistical Mechanics of Labor Markets

NASA Astrophysics Data System (ADS)

Chen, He; Inoue, Jun-ichi

We introduce a probabilistic model of labor markets for university graduates, in particular, in Japan. To make a model of the market efficiently, we take into account several hypotheses. Namely, each company fixes the (business year independent) number of opening positions for newcomers. The ability of gathering newcomers depends on the result of job matching process in past business years. This fact means that the ability of the company is weaken if the company did not make their quota or the company gathered applicants too much over the quota. All university graduates who are looking for their jobs can access the public information about the ranking of companies. Assuming the above essential key points, we construct the local energy function of each company and describe the probability that an arbitrary company gets students at each business year by a Boltzmann-Gibbs distribution. We evaluate the relevant physical quantities such as the employment rate. We find that the system undergoes a sort of `phase transition' from the `good employment phase' to `poor employment phase' when one controls the degree of importance for the ranking.

Investigations on the charge transfer mechanism at donor/acceptor interfaces in the quest for descriptors of organic solar cell performance.

PubMed

Muraoka, Azusa; Fujii, Mikiya; Mishima, Kenji; Matsunaga, Hiroki; Benten, Hiroaki; Ohkita, Hideo; Ito, Shinzaburo; Yamashita, Koichi

2018-05-07

Herein, we theoretically and experimentally investigated the mechanisms of charge separation processes of organic thin-film solar cells. PTB7, PTB1, and PTBF2 have been chosen as donors and PC 71 BM has been chosen as an acceptor considering that effective charge generation depends on the difference between the material combinations. Experimental results of transient absorption spectroscopy show that the hot process is a key step for determining external quantum efficiency (EQE) in these systems. From the quantum chemistry calculations, it has been found that EQE tends to increase as the transferred charge, charge transfer distance, and variation of dipole moments between the ground and excited states of the donor/acceptor complexes increase; this indicates that these physical quantities are a good descriptor to assess the donor-acceptor charge transfer quality contributing to the solar cell performance. We propose that designing donor/acceptor interfaces with large values of charge transfer distance and variation of dipole moments of the donor/acceptor complexes is a prerequisite for developing high-efficiency polymer/PCBM solar cells.

Difference in quantity discrimination in dogs and wolves.

PubMed

Range, Friederike; Jenikejew, Julia; Schröder, Isabelle; Virányi, Zsófia

2014-01-01

Certain aspects of social life, such as engaging in intergroup conflicts, as well as challenges posed by the physical environment, may facilitate the evolution of quantity discrimination. In lack of excessive comparative data, one can only hypothesize about its evolutionary origins, but human-raised wolves performed well when they had to choose the larger of two sets of 1-4 food items that had been sequentially placed into two opaque cans. Since in such paradigms, the animals never see the entire content of either can, their decisions are thought to rely on mental representation of the two quantities rather than on some perceptual factors such as the overall volume or surface area of the two amounts. By equaling the time that it takes to enter each quantity into the cans or the number of items entered, one can further rule out the possibility that animals simply choose based on the amount of time needed to present the two quantities. While the wolves performed well even in such a control condition, dogs failed to choose the larger one of two invisible quantities in another study using a similar paradigm. Because this disparity could be explained by procedural differences, in the current study, we set out to test dogs that were raised and kept identically as the previously tested wolves using the same set-up and procedure. Our results confirm the former finding that dogs, in comparison to wolves, have inferior skills to represent quantities mentally. This seems to be in line with Frank's (1980) hypothesis suggesting that domestication altered the information processing of dogs. However, as discussed, also alternative explanations may exist.

DiffPy-CMI-Python libraries for Complex Modeling Initiative

DOE Office of Scientific and Technical Information (OSTI.GOV)

Billinge, Simon; Juhas, Pavol; Farrow, Christopher

2014-02-01

Software to manipulate and describe crystal and molecular structures and set up structural refinements from multiple experimental inputs. Calculation and simulation of structure derived physical quantities. Library for creating customized refinements of atomic structures from available experimental and theoretical inputs.

15 CFR 200.103 - Consulting and advisory services.

Code of Federal Regulations, 2013 CFR

2013-01-01

...., details of design and construction, operational aspects, unusual or extreme conditions, methods of statistical control of the measurement process, automated acquisition of laboratory data, and data reduction... group seminars on the precision measurement of specific types of physical quantities, offering the...

15 CFR 200.103 - Consulting and advisory services.

Code of Federal Regulations, 2011 CFR

2011-01-01

...., details of design and construction, operational aspects, unusual or extreme conditions, methods of statistical control of the measurement process, automated acquisition of laboratory data, and data reduction... group seminars on the precision measurement of specific types of physical quantities, offering the...

Nucleon spin-averaged forward virtual Compton tensor at large Q 2

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hill, Richard J.; Paz, Gil

The nucleon spin-averaged forward virtual Compton tensor determines important physical quantities such as electromagnetically-induced mass differences of nucleons, and two-photon exchange contributions in hydrogen spectroscopy. It depends on two kinematic variables:more » $$\

On Proper Selection of Multihop Relays for Future Enhancement of AeroMACS Networks

NASA Technical Reports Server (NTRS)

Kamali, Behnam; Kerczewski, Robert J.; Apaza, Rafael D.

2015-01-01

As the Aeronautical Mobile Airport Communications System (AeroMACS) has evolved from a technology concept to a deployed communications network over major US airports, it is now time to contemplate whether the existing capacity of AeroMACS is sufficient to meet the demands set forth by all fixed and mobile applications over the airport surface given the AeroMACS constraints regarding bandwidth and transmit power. The underlying idea in this article is to present IEEE 802.16j-based WiMAX as a technology that can address future capacity enhancements and therefore is most feasible for AeroMACS applications. The principal argument in favor IEEE 802.16j technology is the flexible and cost effective extension of radio coverage that is afforded by relay fortified networks, with virtually no increase in the power requirements and virtually no rise in interference levels to co-allocated applications. The IEEE 802.16j-based multihop relay systems are briefly described. The focus is on key features of this technology, frame structure, and its architecture. Next, AeroMACS is described as a WiMAX-based wireless network. The two major relay modes supported by IEEE 802.16j amendment, i.e., transparent and non-transparent are described. The benefits of employing multihop relays are listed. Some key challenges related to incorporating relays into AeroMACS networks are discussed. The selection of relay type in a broadband wireless network affects a number of network parameters such as latency, signal overhead, PHY (Scalable Physical Layer) and MAC (Media Access Layer) layer protocols, consequently it can alter key network quantities of throughput and QoS (Quality of Service).

Safe pill-dispensing.

PubMed

Testa, Massimiliano; Pollard, John

2007-01-01

Each patient is supplied with a smart-card containing a Radio Frequency IDentification (RFID) chip storing a unique identification code. The patient places the Smart-card on a pill-dispenser unit containing an RFID reader. The RFID chip is read and the code sent to a Base-station via a wireless Bluetooth link. A database containing both patient details and treatment information is queried at the Base-station using the RFID as the search key. The patient's treatment data (i.e., drug names, quantities, time, etc.) are retrieved and sent back to the pill-dispenser unit via Bluetooth. Appropriate quantities of the required medications are automatically dispensed, unless the patient has already taken his/her daily dose. Safe, confidential communication and operation is ensured.

Distillers Dried Grains with Solubles (DDGS) – A Key to the Fuel Ethanol Industry

USDA-ARS?s Scientific Manuscript database

Corn-based ethanol in the U.S. has dramatically increased in recent years; so has the quantity of associated coproducts. Nonfermentable components are removed from the process as whole stillage, centrifuged to remove water – which is then evaporated to produce condensed distillers solubles (CDS), a...

10 CFR 75.4 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 274b. of the Act. Batch means a portion of nuclear material handled as a unit for accounting purposes at a key measurement point and for which the composition and quantity are defined by a single set of specifications or measurements. The nuclear material may be in bulk form or contained in a number of separate...

The Experiences of Vietnamese University Faculty in Relation to Their Faculty Development

ERIC Educational Resources Information Center

Phuong, Tam T.; McLean, Gary N.

2016-01-01

As Vietnam higher education has explored ways to integrate into the international community, professional development of faculty is becoming a key element. However, there is a significant shortage of faculty development (FD) in Vietnam, resulting in a large gap in quality, quantity, and qualifications between Vietnamese faculty and their…

Phomopsis and Sudden Oak Death: A Tale of Two Nursery Nuisances

Treesearch

Bruce D. Moltzan

2006-01-01

Tree nurseries, by their very nature, provide key components of the disease triangle (pathogen, host, and environment) simply by the widespread planting of susceptible host(s) grown under optimal conditions. Pathogens can severely impact the quality and quantity of seedling stock, making pest management a high priority in successful nursery practice. Careful...

Sales Training: Effects of Spaced Practice on Training Transfer

ERIC Educational Resources Information Center

Kauffeld, Simone; Lehmann-Willenbrock, Nale

2010-01-01

Purpose: The benefits of spaced training over massed training practice are well established in the laboratory setting. In a field study design with sales trainings, the purpose of this paper is to investigate the effects of spaced compared with massed practice on transfer quantity and quality, sales competence, and key figures.…

Basic Theory of Fractional Conformal Invariance of Mei Symmetry and its Applications to Physics

NASA Astrophysics Data System (ADS)

Luo, Shao-Kai; Dai, Yun; Yang, Ming-Jing; Zhang, Xiao-Tian

2018-04-01

In this paper, we present a basic theory of fractional dynamics, i.e., the fractional conformal invariance of Mei symmetry, and find a new kind of conserved quantity led by fractional conformal invariance. For a dynamical system that can be transformed into fractional generalized Hamiltonian representation, we introduce a more general kind of single-parameter fractional infinitesimal transformation of Lie group, the definition and determining equation of fractional conformal invariance are given. And then, we reveal the fractional conformal invariance of Mei symmetry, and the necessary and sufficient condition whether the fractional conformal invariance would be the fractional Mei symmetry is found. In particular, we present the basic theory of fractional conformal invariance of Mei symmetry and it is found that, using the new approach, we can find a new kind of conserved quantity; as a special case, we find that an autonomous fractional generalized Hamiltonian system possesses more conserved quantities. Also, as the new method's applications, we, respectively, find the conserved quantities of a fractional general relativistic Buchduhl model and a fractional Duffing oscillator led by fractional conformal invariance of Mei symmetry.

Integrating Key Competences in School Physical Education Programmes

ERIC Educational Resources Information Center

Lleixà, Teresa; González-Arévalo, Carles; Braz-Vieira, Marcelo

2016-01-01

In 2006, the European Union published its recommendations on competences for lifelong learning. Since then, key competences have been integrated into the official curriculum in Spain. The objectives of the present study are: a) to describe the strategies used most frequently by physical education teachers to incorporate key competences in their…

The influence of neighbourhood green space on children's physical activity and screen time: findings from the longitudinal study of Australian children.

PubMed

Sanders, Taren; Feng, Xiaoqi; Fahey, Paul P; Lonsdale, Chris; Astell-Burt, Thomas

2015-09-30

It is often hypothesised that neighbourhood green space may help prevent well-known declines in physical activity and increases in sedentary behaviour that occur across childhood. As most studies in this regard are cross-sectional, the purpose of our study was to use longitudinal data to examine whether green space promotes active lifestyles as children grow older. Data came from participants (n = 4983; age = 4-5) of the Longitudinal Study of Australian Children, a nationally representative study on health and child development. Physical activity and screen time were measured biennially (2004-2012) using questionnaires and time use diaries. Quantity of neighbourhood green space was objectively measured using Australian Bureau of Statistics mesh block data for each participant's statistical area level 2. Multilevel regression was used to test for associations between physical activity and screen time with green space quantity, adjusting for socio-economic confounders. Boys living in areas with 10% more neighbourhood green space had a: 7% (95% CI = 1.02, 1.13) greater odds of choosing physically active pastimes; 8% (95 % CI = 0.85, 1.00) lower odds of not enjoying physical activity; 2.3 min reduction in weekend television viewing (95% CI = -4.00, -0.69); and 7% (95% CI = 1.02; 1.12) and 9% (95% CI = 1.03; 1.15) greater odds of meeting physical activity guidelines on weekdays and weekends, respectively. No statistically (or practically) significant results were observed for girls. Current provisions of neighbourhood green space may be more amenable to promoting active lifestyles among boys than girls. Research is needed to explore what types of green space promote active lifestyles in all children.

Physical activity to overcome the adversity of widowhood

PubMed Central

Li, Chu-Shiu; Lee, June Han; Chang, Ly-yun; Liu, Chwen-Chi; Chan, Yan-Lan; Wen, Christopher; Chiu, Mu-Lin; Tsai, Min Kuang; Tsai, Shan Pou; Wai, Jackson Pui Man; Tsao, Chwen Keng; Wu, Xifeng; Wen, Chi Pang

2016-01-01

Abstract Widowhood has been increasingly encountered because of increasing longevity of women, often characterized by social stigmatization and poor physical and mental health. However, applied research to overcome its adversity has been quite limited. The goal of this study is to explore the role of physical activity in improving the health of widows. A cohort of 446,582 adults in Taiwan who successively participated in a comprehensive medical screening program starting in 1994, including 232,788 women, was followed up for mortality until 2008. Each individual provided detailed health history, and extensive lab tests results. The number of widows increased with time trend. Every other woman above age 65 was a widow (44%). Widows were less active, more obese, and smoked and drank more, had sleep problems, were more depressed with taking sedatives or psychoactive drugs, leading to more suicides. In the global development of health policies by World Health Organization (WHO), physical activity is one of the main factors to reverse poor health. The poor health of inactive widow was mitigated when becoming fully active in this study. Exercise not only reduced the observed 18% increase in all-cause mortality, but also gained 4 years and as much as 14% mortality advantage over the married but inactive. More importantly, becoming physically active energized their mental status, improved sleep quality and quantity, reduced depressions and the need for psychoactive drugs, and increased socialization circles. Widows, a rapidly growing and socially stigmatized group, suffered from social and financial inequality and tended to develop poorer health. Sustained physical activity could be one of the ways for them to overcome and reverse some of the physical and mental adversities of widowhood, and improve their quality and quantity of life. PMID:27512856

KEY COMPARISON: Final report on APMP.M.P-K6.1 pneumatic key comparison from 20 kPa to 105 kPa in gauge mode

NASA Astrophysics Data System (ADS)

Hung, Chen-Chuan; Jian, Wu; Changpan, Tawat

2009-01-01

This report describes the key comparison APMP.M.P-K6.1 among the three national metrology institutes, Center for Measurement Standards-ITRI (CMS-ITRI, Taiwan), SPRING Singapore and National Institute of Metrology (NIMT), in the pressure range from 20 kPa to 105 kPa in gas media and gauge mode executed during the period April 2003 to April 2004. This comparison was conducted by CMS-ITRI and was based on the calibration procedure of APMP pneumatic pressure comparison APMP.M.P-K6. We intended to link to the CCM.P-K6 key comparison through the APMP.M.P-K6 key comparison by using the proposed linkage method in the APMP.M.P-K6 key comparison to determine a linking factor that can transform the quantities measured in the APMP.M.P-K6.1 key comparison. All three participating institutes used pneumatic piston gauges as their pressure standards. The Ruska 2465 gas-operated piston-cylinder assembly TL-1409 used as transfer standard offered by CMS-ITRI was calibrated three times by the pilot institute during the comparison period and showed that it was very stable after evaluation. The comparison was conducted on the basis of cross-float experiments to determine the effective area of transfer standards from the national standards of three institutes. The comparison results (as shown in Table 6) were equivalent to the CCM.P-K6 comparison and the relative bilateral degrees of equivalence between two laboratories were smaller than 39.7 × 10-6 from 20 kPa to 105 kPa. These results showed all participating institutes measuring the same quantity in the whole pressure range lay within their expanded uncertainty with confidence level 95%. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCM, according to the provisions of the CIPM Mutual Recognition Arrangement (MRA).

Optimal ordering quantities for substitutable deteriorating items under joint replenishment with cost of substitution

NASA Astrophysics Data System (ADS)

Mishra, Vinod Kumar

2017-09-01

In this paper we develop an inventory model, to determine the optimal ordering quantities, for a set of two substitutable deteriorating items. In this inventory model the inventory level of both items depleted due to demands and deterioration and when an item is out of stock, its demands are partially fulfilled by the other item and all unsatisfied demand is lost. Each substituted item incurs a cost of substitution and the demands and deterioration is considered to be deterministic and constant. Items are order jointly in each ordering cycle, to take the advantages of joint replenishment. The problem is formulated and a solution procedure is developed to determine the optimal ordering quantities that minimize the total inventory cost. We provide an extensive numerical and sensitivity analysis to illustrate the effect of different parameter on the model. The key observation on the basis of numerical analysis, there is substantial improvement in the optimal total cost of the inventory model with substitution over without substitution.

The plasma separation process as a pre-cursor for large scale radioisotope production

NASA Astrophysics Data System (ADS)

Stevenson, Nigel R.

2001-07-01

Radioisotope production generally employs either accelerators or reactors to convert stable (usually enriched) isotopes into the desired product species. Radioisotopes have applications in industry, environmental sciences, and most significantly in medicine. The production of many potentially useful radioisotopes is significantly hindered by the lack of availability or by the high cost of key enriched stable isotopes. To try and meet this demand, certain niche enrichment processes have been developed and commercialized. Calutrons, centrifuges, and laser separation processes are some of the devices and techniques being employed to produce large quantities of selective enriched stable isotopes. Nevertheless, the list of enriched stable isotopes in sufficient quantities remains rather limited and this continues to restrict the availability of many radioisotopes that otherwise could have a significant impact on society. The Plasma Separation Process is a newly available commercial technique for producing large quantities of a wide range of enriched isotopes and thereby holds promise of being able to open the door to producing new and exciting applications of radioisotopes in the future.

Uncertainty Calculations in the First Introductory Physics Laboratory

NASA Astrophysics Data System (ADS)

Rahman, Shafiqur

2005-03-01

Uncertainty in a measured quantity is an integral part of reporting any experimental data. Consequently, Introductory Physics laboratories at many institutions require that students report the values of the quantities being measured as well as their uncertainties. Unfortunately, given that there are three main ways of calculating uncertainty, each suitable for particular situations (which is usually not explained in the lab manual), this is also an area that students feel highly confused about. It frequently generates large number of complaints in the end-of-the semester course evaluations. Students at some institutions are not asked to calculate uncertainty at all, which gives them a fall sense of the nature of experimental data. Taking advantage of the increased sophistication in the use of computers and spreadsheets that students are coming to college with, we have completely restructured our first Introductory Physics Lab to address this problem. Always in the context of a typical lab, we now systematically and sequentially introduce the various ways of calculating uncertainty including a theoretical understanding as opposed to a cookbook approach, all within the context of six three-hour labs. Complaints about the lab in student evaluations have dropped by 80%. * supported by a grant from A. V. Davis Foundation

49 CFR 242.509 - Hearings.

Code of Federal Regulations, 2012 CFR

2012-10-01

... proffered orally shall be transcribed and made a part of the record. Any physical evidence or written... presiding officer may authorize discovery of the types and quantities which in the presiding officer's... impose appropriate non-monetary sanctions, including limitations as to the presentation of evidence and...

49 CFR 242.509 - Hearings.

Code of Federal Regulations, 2014 CFR

2014-10-01

... proffered orally shall be transcribed and made a part of the record. Any physical evidence or written... presiding officer may authorize discovery of the types and quantities which in the presiding officer's... impose appropriate non-monetary sanctions, including limitations as to the presentation of evidence and...

49 CFR 242.509 - Hearings.

Code of Federal Regulations, 2013 CFR

2013-10-01

... proffered orally shall be transcribed and made a part of the record. Any physical evidence or written... presiding officer may authorize discovery of the types and quantities which in the presiding officer's... impose appropriate non-monetary sanctions, including limitations as to the presentation of evidence and...

10 CFR 40.13 - Unimportant quantities of source material.

Code of Federal Regulations, 2014 CFR

2014-01-01

... receives, possesses, uses, transfers or delivers source material in any chemical mixture, compound... source material; but not including commercially manufactured glass brick, pane glass, ceramic tile, or... in this subparagraph shall not be deemed to authorize the chemical, physical or metallurgical...

10 CFR 40.13 - Unimportant quantities of source material.

Code of Federal Regulations, 2013 CFR

2013-01-01

... receives, possesses, uses, transfers or delivers source material in any chemical mixture, compound... percent by weight source material; but not including commercially manufactured glass brick, pane glass... contained in this subparagraph shall not be deemed to authorize the chemical, physical or metallurgical...

10 CFR 40.13 - Unimportant quantities of source material.

Code of Federal Regulations, 2012 CFR

2012-01-01

... receives, possesses, uses, transfers or delivers source material in any chemical mixture, compound... percent by weight source material; but not including commercially manufactured glass brick, pane glass... contained in this subparagraph shall not be deemed to authorize the chemical, physical or metallurgical...

Antihydrogen on tap

NASA Astrophysics Data System (ADS)

Charlton, Michael

2005-03-01

Plentiful quantities of antihydrogen, the bound state system of the antiparticles the positron and the antiproton, have recently been made under very controlled conditions in experiments at the European Laboratory of Particle Physics (CERN) near Geneva. In this article I describe how that was done, and why.

Mathematical structure of unit systems

NASA Astrophysics Data System (ADS)

Kitano, Masao

2013-05-01

We investigate the mathematical structure of unit systems and the relations between them. Looking over the entire set of unit systems, we can find a mathematical structure that is called preorder (or quasi-order). For some pair of unit systems, there exists a relation of preorder such that one unit system is transferable to the other unit system. The transfer (or conversion) is possible only when all of the quantities distinguishable in the latter system are always distinguishable in the former system. By utilizing this structure, we can systematically compare the representations in different unit systems. Especially, the equivalence class of unit systems (EUS) plays an important role because the representations of physical quantities and equations are of the same form in unit systems belonging to an EUS. The dimension of quantities is uniquely defined in each EUS. The EUS's form a partially ordered set. Using these mathematical structures, unit systems and EUS's are systematically classified and organized as a hierarchical tree.

Spherically symmetric charged black holes in f(R) gravitational theories

NASA Astrophysics Data System (ADS)

Nashed, G. G. L.

2018-01-01

In this study, we have derived electric and magnetic spherically symmetric black holes for the class f(R)=R+ζ R2 without assuming any restrictions on the Ricci scalar. These black holes asymptotically behave as the de Sitter spacetime under certain constrains. We have shown that the magnetic charge contributes in the metric spacetime similarly to the electric charge. The most interesting feature of some of these black holes is the fact that the Cauchy horizon is not identical to the event horizon. We have calculated the invariants of Ricci and Kretschmann scalars to investigate the nature of singularities of such black holes. Also, we have calculated the conserved quantities to match the constants of integration with the physical quantities. Finally, the thermodynamical quantities, like Hawking temperature, entropy, etc., have been evaluated and the validity of the first law of thermodynamics has been verified.

Quantity Effect of Radial Cracks on the Cracking Propagation Behavior and the Crack Morphology

PubMed Central

Chen, Jingjing; Xu, Jun; Liu, Bohan; Yao, Xuefeng; Li, Yibing

2014-01-01

In this letter, the quantity effect of radial cracks on the cracking propagation behavior as well as the circular crack generation on the impacted glass plate within the sandwiched glass sheets are experimentally investigated via high-speed photography system. Results show that the radial crack velocity on the backing glass layer decreases with the crack number under the same impact conditions during large quantities of repeated experiments. Thus, the “energy conversion factor” is suggested to elucidate the physical relation between the cracking number and the crack propagation speed. Besides, the number of radial crack also takes the determinative effect in the crack morphology of the impacted glass plate. This study may shed lights on understanding the cracking and propagation mechanism in laminated glass structures and provide useful tool to explore the impact information on the cracking debris. PMID:25048684

Effects of ammonia and hydrogen sulfide on physical and biochemical properties of the claw horn of Holstein cows

PubMed Central

Higuchi, Hidetoshi; Kurumado, Hisatoshi; Mori, Maya; Degawa, Aiko; Fujisawa, Hideyo; Kuwano, Atsutoshi; Nagahata, Hajime

2009-01-01

The effects of ammonia and hydrogen sulfide on the physical and biochemical properties of the claw horn of Holstein cows were evaluated. Significant (P < 0.05, 0.01) decreases in hardness and elasticity were found in claw horns soaked in ammonia (NH3) and hydrogen sulfide (H2S) solutions compared with those that were soaked in water for 12, 24, and 48 h. Water absorption rate, as a indicator of permeability barrier function, increased significantly (P < 0.05) over time during the soaking period and was found to be dependent on the concentrations of NH3 and H2S in the solutions. The contents of ceramide, the main lipid component for the permeability barrier system of the stratum corneum, were significantly decreased in claw horns soaked in NH3 and H2S solutions compared with the values before soaking. Quantities of eluted protein released from claw horns treated with NH3 and H2S solutions were approximately 20 times and 30 to 40 times greater than those released from claw horns treated with water alone. Interestingly, the quantities of cytokeratin 10, the main cytoskeletal protein of the stratum corneum, eluted from claw horns treated with NH3 and H2S solutions were markedly greater than the quantity released from horns soaked in water. Our results suggest that abnormal changes in the physical property of claw horn caused by NH3 and H2S treatment are due to disruption of the biochemical property of the claw horn induced by these chemical agents derived from slurry. PMID:19337390

Physics holo.lab learning experience: using smartglasses for augmented reality labwork to foster the concepts of heat conduction

NASA Astrophysics Data System (ADS)

Strzys, M. P.; Kapp, S.; Thees, M.; Klein, P.; Lukowicz, P.; Knierim, P.; Schmidt, A.; Kuhn, J.

2018-05-01

Fundamental concepts of thermodynamics rely on abstract physical quantities such as energy, heat and entropy, which play an important role in the process of interpreting thermal phenomena and statistical mechanics. However, these quantities are not covered by human visual perception, and since heat sensation is purely qualitative and easy to deceive, an intuitive understanding often is lacking. Today immersive technologies like head-mounted displays of the newest generation, especially HoloLens, allow for high-quality augmented reality learning experiences, which can overcome this gap in human perception by presenting different representations of otherwise invisible quantities directly in the field of view of the user on the experimental apparatus, which simultaneously avoids a split-attention effect. In a mixed reality (MR) scenario as presented in this paper—which we call a holo.lab—human perception can be extended to the thermal regime by presenting false-color representations of the temperature of objects as a virtual augmentation directly on the real object itself in real-time. Direct feedback to experimental actions of the users in the form of different representations allows for immediate comparison to theoretical principles and predictions and therefore is supposed to intensify the theory–experiment interactions and to increase students’ conceptual understanding. We tested this technology for an experiment on thermal conduction of metals in the framework of undergraduate laboratories. A pilot study with treatment and control groups (N = 59) showed a small positive effect of MR on students’ performance measured with a standardized concept test for thermodynamics, pointing to an improvement of the understanding of the underlying physical concepts. These findings indicate that complex experiments could benefit even more from augmentation. This motivates us to enrich further experiments with MR.

NASA Langley's Approach to the Sandia's Structural Dynamics Challenge Problem

NASA Technical Reports Server (NTRS)

Horta, Lucas G.; Kenny, Sean P.; Crespo, Luis G.; Elliott, Kenny B.

2007-01-01

The objective of this challenge is to develop a data-based probabilistic model of uncertainty to predict the behavior of subsystems (payloads) by themselves and while coupled to a primary (target) system. Although this type of analysis is routinely performed and representative of issues faced in real-world system design and integration, there are still several key technical challenges that must be addressed when analyzing uncertain interconnected systems. For example, one key technical challenge is related to the fact that there is limited data on target configurations. Moreover, it is typical to have multiple data sets from experiments conducted at the subsystem level, but often samples sizes are not sufficient to compute high confidence statistics. In this challenge problem additional constraints are placed as ground rules for the participants. One such rule is that mathematical models of the subsystem are limited to linear approximations of the nonlinear physics of the problem at hand. Also, participants are constrained to use these models and the multiple data sets to make predictions about the target system response under completely different input conditions. Our approach involved initially the screening of several different methods. Three of the ones considered are presented herein. The first one is based on the transformation of the modal data to an orthogonal space where the mean and covariance of the data are matched by the model. The other two approaches worked solutions in physical space where the uncertain parameter set is made of masses, stiffnesses and damping coefficients; one matches confidence intervals of low order moments of the statistics via optimization while the second one uses a Kernel density estimation approach. The paper will touch on all the approaches, lessons learned, validation 1 metrics and their comparison, data quantity restriction, and assumptions/limitations of each approach. Keywords: Probabilistic modeling, model validation, uncertainty quantification, kernel density

The Elephants in the Room: Sex, HIV, and LGBT Populations in MENA. Intersectionality in Lebanon Comment on "Improving the Quality and Quantity of HIV Data in the Middle East and North Africa: Key Challenges and Ways Forward".

PubMed

Kaplan, Rachel L; El Khoury, Cynthia

2016-12-04

In response to this insightful editorial, we wish to provide commentary that seeks to highlight recent successes and illuminate the often unspoken hurdles at the intersections of culture, politics, and taboo. We focus on sexual transmission and draw examples from Lebanon, where the pursuit of data in quality and quantity is teaching us lessons about the way forward and where we are experiencing many of the challenges referenced in the editorial such as discrepancies between national statistics and rates derived via research as well as the impact of protracted political conflict and displacement. Two important points were raised in the editorial about HIV in Middle East and North Africa (MENA) that we would like to expand further: (1) The epidemic is largely driven by drug-related and sexual behavior among key populations; and (2) Several key populations continue to be criminalized and excluded from surveillance programs. © 2017 The Author(s); Published by Kerman University of Medical Sciences. This is an open-access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Resource Quantity and Quality Determine the Inter-Specific Associations between Ecosystem Engineers and Resource Users in a Cavity-Nest Web

PubMed Central

Robles, Hugo; Martin, Kathy

2013-01-01

While ecosystem engineering is a widespread structural force of ecological communities, the mechanisms underlying the inter-specific associations between ecosystem engineers and resource users are poorly understood. A proper knowledge of these mechanisms is, however, essential to understand how communities are structured. Previous studies suggest that increasing the quantity of resources provided by ecosystem engineers enhances populations of resource users. In a long-term study (1995-2011), we show that the quality of the resources (i.e. tree cavities) provided by ecosystem engineers is also a key feature that explains the inter-specific associations in a tree cavity-nest web. Red-naped sapsuckers ( Sphyrapicus nuchalis ) provided the most abundant cavities (52% of cavities, 0.49 cavities/ha). These cavities were less likely to be used than other cavity types by mountain bluebirds ( Sialia currucoides ), but provided numerous nest-sites (41% of nesting cavities) to tree swallows ( Tachycineta bicolour ). Swallows experienced low reproductive outputs in northern flicker ( Colaptes auratus ) cavities compared to those in sapsucker cavities (1.1 vs. 2.1 fledglings/nest), but the highly abundant flickers (33% of cavities, 0.25 cavities/ha) provided numerous suitable nest-sites for bluebirds (58%). The relative shortage of cavities supplied by hairy woodpeckers ( Picoides villosus ) and fungal/insect decay (<10% of cavities each, <0.09 cavities/ha) provided fewer breeding opportunities (<15% of nests), but represented high quality nest-sites for both bluebirds and swallows. Because both the quantity and quality of resources supplied by different ecosystem engineers may explain the amount of resources used by each resource user, conservation strategies may require different management actions to be implemented for the key ecosystem engineer of each resource user. We, therefore, urge the incorporation of both resource quantity and quality into models that assess community dynamics to improve conservation actions and our understanding of ecological communities based on ecosystem engineering. PMID:24040324

Resource quantity and quality determine the inter-specific associations between ecosystem engineers and resource users in a cavity-nest web.

PubMed

Robles, Hugo; Martin, Kathy

2013-01-01

While ecosystem engineering is a widespread structural force of ecological communities, the mechanisms underlying the inter-specific associations between ecosystem engineers and resource users are poorly understood. A proper knowledge of these mechanisms is, however, essential to understand how communities are structured. Previous studies suggest that increasing the quantity of resources provided by ecosystem engineers enhances populations of resource users. In a long-term study (1995-2011), we show that the quality of the resources (i.e. tree cavities) provided by ecosystem engineers is also a key feature that explains the inter-specific associations in a tree cavity-nest web. Red-naped sapsuckers (Sphyrapicusnuchalis) provided the most abundant cavities (52% of cavities, 0.49 cavities/ha). These cavities were less likely to be used than other cavity types by mountain bluebirds (Sialiacurrucoides), but provided numerous nest-sites (41% of nesting cavities) to tree swallows (Tachycinetabicolour). Swallows experienced low reproductive outputs in northern flicker (Colaptesauratus) cavities compared to those in sapsucker cavities (1.1 vs. 2.1 fledglings/nest), but the highly abundant flickers (33% of cavities, 0.25 cavities/ha) provided numerous suitable nest-sites for bluebirds (58%). The relative shortage of cavities supplied by hairy woodpeckers (Picoidesvillosus) and fungal/insect decay (<10% of cavities each, <0.09 cavities/ha) provided fewer breeding opportunities (<15% of nests), but represented high quality nest-sites for both bluebirds and swallows. Because both the quantity and quality of resources supplied by different ecosystem engineers may explain the amount of resources used by each resource user, conservation strategies may require different management actions to be implemented for the key ecosystem engineer of each resource user. We, therefore, urge the incorporation of both resource quantity and quality into models that assess community dynamics to improve conservation actions and our understanding of ecological communities based on ecosystem engineering.

A New Class of Almost Ricci Solitons and Their Physical Interpretation

PubMed Central

2016-01-01

We establish a link between a connection symmetry, called conformal collineation, and almost Ricci soliton (in particular Ricci soliton) in reducible Ricci symmetric semi-Riemannian manifolds. As a physical application, by investigating the kinematic and dynamic properties of almost Ricci soliton manifolds, we present a physical model of imperfect fluid spacetimes. This model gives a general relation between the physical quantities (u, μ, p, α, η, σ ij) of the matter tensor of the field equations and does not provide any exact solution. Therefore, we propose further study on finding exact solutions of our viscous fluid physical model for which it is required that the fluid velocity vector u be tilted. We also suggest two open problems. PMID:28044145

Self-Assembled Resonance Energy Transfer Keys for Secure Communication over Classical Channels.

PubMed

Nellore, Vishwa; Xi, Sam; Dwyer, Chris

2015-12-22

Modern authentication and communication protocols increasingly use physical keys in lieu of conventional software-based keys for security. This shift is primarily driven by the ability to derive a unique, unforgeable signature from a physical key. The sole demonstration of an unforgeable key, thus far, has been through quantum key distribution, which suffers from limited communication distances and expensive infrastructure requirements. Here, we show a method for creating unclonable keys by molecular self-assembly of resonance energy transfer (RET) devices. It is infeasible to clone the RET-key due to the inability to characterize the key using current technology, the large number of input-output combinations per key, and the variation of the key's response with time. However, the manufacturer can produce multiple identical devices, which enables inexpensive, secure authentication and communication over classical channels, and thus any distance. Through a detailed experimental survey of the nanoscale keys, we demonstrate that legitimate users are successfully authenticated 99.48% of the time and the false-positives are only 0.39%, over two attempts. We estimate that a legitimate user would have a computational advantage of more than 10(340) years over an attacker. Our method enables the discovery of physical key based multiparty authentication and communication schemes that are both practical and possess unprecedented security.

Quantum-locked key distribution at nearly the classical capacity rate.

PubMed

Lupo, Cosmo; Lloyd, Seth

2014-10-17

Quantum data locking is a protocol that allows for a small secret key to (un)lock an exponentially larger amount of information, hence yielding the strongest violation of the classical one-time pad encryption in the quantum setting. This violation mirrors a large gap existing between two security criteria for quantum cryptography quantified by two entropic quantities: the Holevo information and the accessible information. We show that the latter becomes a sensible security criterion if an upper bound on the coherence time of the eavesdropper's quantum memory is known. Under this condition, we introduce a protocol for secret key generation through a memoryless qudit channel. For channels with enough symmetry, such as the d-dimensional erasure and depolarizing channels, this protocol allows secret key generation at an asymptotic rate as high as the classical capacity minus one bit.

The influence of intuition and communication language in generating student conceptions

NASA Astrophysics Data System (ADS)

Handhika, J.; Cari, C.; Suparmi, A.; Sunarno, W.

2017-11-01

This research aims to describe the influence of intuition and communication language in generating student conceptions. The conception diagnostic test is used to reveal student conception. The diagnostic test results described and communication language profiled by giving instruction to students to make sentences using physics quantities. Sentences expressed by students are reduced and profiled potential effects. Obtained information that (1) Students generalize non-scientific experience (based on feeling) into the physics problem. This process caused misconception. Communication language can make the students difficult to understand the concept because of the difference meaning of communication and physics language.

The physics of powerlifting

NASA Astrophysics Data System (ADS)

Radenković, Lazar; Nešić, Ljubiša

2018-05-01

The main contribution of this paper is didactic adaptation of the biomechanical analysis of the three main lifts in powerlifting (squat, bench press, deadlift). We used simple models that can easily be understood by undergraduate college students to estimate the values of various physical quantities during powerlifting. Specifically, we showed how plate choice affects the bench press and estimated spine loads and torques at hip and knee during lifting. Theoretical calculations showed good agreement with experimental data, proving that the models are valid.

Review of lattice results concerning low-energy particle physics: Flavour Lattice Averaging Group (FLAG).

PubMed

Aoki, S; Aoki, Y; Bečirević, D; Bernard, C; Blum, T; Colangelo, G; Della Morte, M; Dimopoulos, P; Dürr, S; Fukaya, H; Golterman, M; Gottlieb, Steven; Hashimoto, S; Heller, U M; Horsley, R; Jüttner, A; Kaneko, T; Lellouch, L; Leutwyler, H; Lin, C-J D; Lubicz, V; Lunghi, E; Mawhinney, R; Onogi, T; Pena, C; Sachrajda, C T; Sharpe, S R; Simula, S; Sommer, R; Vladikas, A; Wenger, U; Wittig, H

2017-01-01

We review lattice results related to pion, kaon, D - and B -meson physics with the aim of making them easily accessible to the particle-physics community. More specifically, we report on the determination of the light-quark masses, the form factor [Formula: see text], arising in the semileptonic [Formula: see text] transition at zero momentum transfer, as well as the decay constant ratio [Formula: see text] and its consequences for the CKM matrix elements [Formula: see text] and [Formula: see text]. Furthermore, we describe the results obtained on the lattice for some of the low-energy constants of [Formula: see text] and [Formula: see text] Chiral Perturbation Theory. We review the determination of the [Formula: see text] parameter of neutral kaon mixing as well as the additional four B parameters that arise in theories of physics beyond the Standard Model. The latter quantities are an addition compared to the previous review. For the heavy-quark sector, we provide results for [Formula: see text] and [Formula: see text] (also new compared to the previous review), as well as those for D - and B -meson-decay constants, form factors, and mixing parameters. These are the heavy-quark quantities most relevant for the determination of CKM matrix elements and the global CKM unitarity-triangle fit. Finally, we review the status of lattice determinations of the strong coupling constant [Formula: see text].

Foundations of Tensor Analysis for Students of Physics and Engineering With an Introduction to the Theory of Relativity

NASA Technical Reports Server (NTRS)

Kolecki, Joseph C.

2005-01-01

Tensor analysis is one of the more abstruse, even if one of the more useful, higher math subjects enjoined by students of physics and engineering. It is abstruse because of the intellectual gap that exists between where most physics and engineering mathematics leave off and where tensor analysis traditionally begins. It is useful because of its great generality, computational power, and compact, easy to use, notation. This paper bridges the intellectual gap. It is divided into three parts: algebra, calculus, and relativity. Algebra: In tensor analysis, coordinate independent quantities are sought for applications in physics and engineering. Coordinate independence means that the quantities have such coordinate transformations as to leave them invariant relative to a particular observer s coordinate system. Calculus: Non-zero base vector derivatives contribute terms to dynamical equations that correspond to pseudoaccelerations in accelerated coordinate systems and to curvature or gravity in relativity. These derivatives have a specific general form in tensor analysis. Relativity: Spacetime has an intrinsic geometry. Light is the tool for investigating that geometry. Since the observed geometry of spacetime cannot be made to match the classical geometry of Euclid, Einstein applied another more general geometry differential geometry. The merger of differential geometry and cosmology was accomplished in the theory of relativity. In relativity, gravity is equivalent to curvature.

Feasibility and Definition of a Limited-Scale Lunar Polar Volatiles Prospecting Mission

NASA Astrophysics Data System (ADS)

Heldmann, J. L.; Elphic, R. C.; Colaprete, A.; Beyer, R. A.; Fong, T.; Cockrell, J.; Pedersen, L.

2011-12-01

The recent Lunar Crater Observing and Sensing Satellite (LCROSS) mission has provided evidence for significant amounts of cold-trapped volatiles in Cabeus crater near the Moon's south pole. Moreover, LRO/Diviner measurements of extremely cold lunar polar surface temperatures imply that volatiles can be stable outside of areas of strict permanent shadow. These discoveries hint at potentially extensive near-surface deposits at both lunar poles. The physical state, composition and distribution of these volatiles are key scientific issues that relate to source and emplacement mechanisms. These issues are also important for enabling lunar in situ resource utilization (ISRU). An assessment of the feasibility of cold-trapped volatile ISRU requires a priori information regarding the location, form, quantity, and potential for extraction of available resources. A small robotic mission to a persistently shadowed but briefly sunlit location with suitable environmental conditions (e.g., short periods of oblique sunlight and subsurface cryogenic temperatures which permit volatile trapping) can help answer these scientific and exploration questions. Key parameters must be defined in order to identify suitable landing sites, plan surface operations, and achieve mission success. To address this need, we have conducted an initial study for a lunar polar volatile prospecting mission, assuming the use of a solar-powered robotic lander and rover. Here we present the mission concept, goals and objectives, and landing site selection analysis for a short-duration, landed, solar-powered mission to a volatile-rich site.

Feasibility and Definition of a Lunar Polar Volatiles Prospecting Mission

NASA Technical Reports Server (NTRS)

Heldmann, Jennifer; Elphic, Richard; Colaprete, Anthony; Fong, Terry; Pedersen, Liam; Beyer, Ross; Cockrell, James

2012-01-01

The recent Lunar Crater Observing and Sensing Satellite (LCROSS) mission has provided evidence for significant amounts of cold trapped volatiles in Cabeus crater near the Moon's south pole. Moreover, LRO/Diviner measurements of extremely cold lunar polar surface temperatures imply that volatiles can be stable outside or areas of strict permanent shadows. These discoveries suggest that orbital neutron spectrometer data point to extensive deposits at both lunar poles. The physical state, composition and distribution of these volatiles are key scientific issues that relate to source and emplacement mechanisms. These issues are also important for enabling lunar in situ resource utilization (ISRU). An assessment of the feasibility of cold-trapped volatile ISRU requires a priori information regarding the location, form, quantity, and potential for extraction of available resources. A robotic mission to a mostly shadowed but briefly .unlit location with suitable environmental conditions (e.g. short periods of oblique sunlight and subsurface cryogenic temperatures which permit volatile trapping) can help answer these scientific and exploration questions. Key parameters must be defined in order to identify suitable landing sites, plan surface operations, and achieve mission success. To address this need, we have conducted an initial study for a lunar polar volatile prospecting mission, assuming the use of a solar-powered robotic lander and rover. Here we present the mission concept, goals and objectives, and landing site selection analysis for a short-duration, landed, solar-powered mission to a potential hydrogen volatile-rich site.

Management of physical health in patients with schizophrenia: practical recommendations.

PubMed

Heald, A; Montejo, A L; Millar, H; De Hert, M; McCrae, J; Correll, C U

2010-06-01

Improved physical health care is a pressing need for patients with schizophrenia. It can be achieved by means of a multidisciplinary team led by the psychiatrist. Key priorities should include: selection of antipsychotic therapy with a low risk of weight gain and metabolic adverse effects; routine assessment, recording and longitudinal tracking of key physical health parameters, ideally by electronic spreadsheets; and intervention to control CVD risk following the same principles as for the general population. A few simple tools to assess and record key physical parameters, combined with lifestyle intervention and pharmacological treatment as indicated, could significantly improve physical outcomes. Effective implementation of strategies to optimise physical health parameters in patients with severe enduring mental illness requires engagement and communication between psychiatrists and primary care in most health settings. Copyright (c) 2010 Elsevier Masson SAS. All rights reserved.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Libby, S B; Weiss, M S

Edward Teller was one of the great physicists of the twentieth century. His career began just after the key ideas of the quantum revolution of the 1920's were completed, opening vast areas of physics and chemistry to detailed understanding. Thus, his early work in theoretical physics focused on applying the new quantum theory to the understanding of diverse phenomena. These topics included chemical physics, diamagnetism, and nuclear physics. Later, he made key contributions to statistical mechanics, surface physics, solid state, and plasma physics. In many cases, the ideas in these papers are still rich with important ramifications.

PHYSICAL CHARACTERISTICS AND HEALTH EFFECTS OF AEROSOLS FROM COLLAPSED BUILDINGS

EPA Science Inventory

Airborne pollutants can rise to extreme levels when large buildings fall down. The terrorist attack on New York's World Trade Center (WTC) towers caused the release of an enormous quantity of pulverized building materials and combustion products into the local environment. Partic...

10 CFR 37.25 - Background investigations.

Code of Federal Regulations, 2014 CFR

2014-01-01

... investigation; and attempt to obtain the information from an alternate source. (b) Grandfathering. (1... 10 Energy 1 2014-01-01 2014-01-01 false Background investigations. 37.25 Section 37.25 Energy NUCLEAR REGULATORY COMMISSION PHYSICAL PROTECTION OF CATEGORY 1 AND CATEGORY 2 QUANTITIES OF RADIOACTIVE...

GUIDANCE MANUAL FOR IMPLEMENTING MUNICIPAL STORM WATER MANAGEMENT PROGRAMS; PLANNING AND ADMINISTRATION

EPA Science Inventory

Urbanization and industrial activities around the country have significantly altered the natural landscape of our Nation's watersheds. This, in turn, has adversely affected both the quantity and the quality of storm water runoff and has contributed to the chemical, physical, and...

76 FR 5830 - Manufacturer of Controlled Substances; Notice of Registration

Federal Register 2010, 2011, 2012, 2013, 2014

2011-02-02

... quantities of the listed controlled substances as radiolabeled compounds for biochemical research. No... classes of controlled substances is consistent with the public interest at this time. DEA has investigated... public interest. The investigation has included inspection and testing of the company's physical security...

Mitigating Stress and Supporting Health in Deprived Urban Communities: The Importance of Green Space and the Social Environment.

PubMed

Ward Thompson, Catharine; Aspinall, Peter; Roe, Jenny; Robertson, Lynette; Miller, David

2016-04-22

Environment-health research has shown significant relationships between the quantity of green space in deprived urban neighbourhoods and people's stress levels. The focus of this paper is the nature of access to green space (i.e., its quantity or use) necessary before any health benefit is found. It draws on a cross-sectional survey of 406 adults in four communities of high urban deprivation in Scotland, United Kingdom. Self-reported measures of stress and general health were primary outcomes; physical activity and social wellbeing were also measured. A comprehensive, objective measure of green space quantity around each participant's home was also used, alongside self-report measures of use of local green space. Correlated Component Regression identified the optimal predictors for primary outcome variables in the different communities surveyed. Social isolation and place belonging were the strongest predictors of stress in three out of four communities sampled, and of poor general health in the fourth, least healthy, community. The amount of green space in the neighbourhood, and in particular access to a garden or allotment, were significant predictors of stress. Physical activity, frequency of visits to green space in winter months, and views from the home were predictors of general health. The findings have implications for public health and for planning of green infrastructure, gardens and public open space in urban environments.

Mitigating Stress and Supporting Health in Deprived Urban Communities: The Importance of Green Space and the Social Environment

PubMed Central

Ward Thompson, Catharine; Aspinall, Peter; Roe, Jenny; Robertson, Lynette; Miller, David

2016-01-01

Environment-health research has shown significant relationships between the quantity of green space in deprived urban neighbourhoods and people’s stress levels. The focus of this paper is the nature of access to green space (i.e., its quantity or use) necessary before any health benefit is found. It draws on a cross-sectional survey of 406 adults in four communities of high urban deprivation in Scotland, United Kingdom. Self-reported measures of stress and general health were primary outcomes; physical activity and social wellbeing were also measured. A comprehensive, objective measure of green space quantity around each participant’s home was also used, alongside self-report measures of use of local green space. Correlated Component Regression identified the optimal predictors for primary outcome variables in the different communities surveyed. Social isolation and place belonging were the strongest predictors of stress in three out of four communities sampled, and of poor general health in the fourth, least healthy, community. The amount of green space in the neighbourhood, and in particular access to a garden or allotment, were significant predictors of stress. Physical activity, frequency of visits to green space in winter months, and views from the home were predictors of general health. The findings have implications for public health and for planning of green infrastructure, gardens and public open space in urban environments. PMID:27110803

APPROXIMATING SYMMETRIC POSITIVE SEMIDEFINITE TENSORS OF EVEN ORDER*

PubMed Central

BARMPOUTIS, ANGELOS; JEFFREY, HO; VEMURI, BABA C.

2012-01-01

Tensors of various orders can be used for modeling physical quantities such as strain and diffusion as well as curvature and other quantities of geometric origin. Depending on the physical properties of the modeled quantity, the estimated tensors are often required to satisfy the positivity constraint, which can be satisfied only with tensors of even order. Although the space P02m of 2mth-order symmetric positive semi-definite tensors is known to be a convex cone, enforcing positivity constraint directly on P02m is usually not straightforward computationally because there is no known analytic description of P02m for m > 1. In this paper, we propose a novel approach for enforcing the positivity constraint on even-order tensors by approximating the cone P02m for the cases 0 < m < 3, and presenting an explicit characterization of the approximation Σ2m ⊂ Ω2m for m ≥ 1, using the subset Ω2m⊂P02m of semi-definite tensors that can be written as a sum of squares of tensors of order m. Furthermore, we show that this approximation leads to a non-negative linear least-squares (NNLS) optimization problem with the complexity that equals the number of generators in Σ2m. Finally, we experimentally validate the proposed approach and we present an application for computing 2mth-order diffusion tensors from Diffusion Weighted Magnetic Resonance Images. PMID:23285313

Diffusion thermo effects on unsteady MHD free convection flow of a Kuvshinski fluid past a vertical porous plate in slip flow regime

NASA Astrophysics Data System (ADS)

Narsu, Sivakumar; Rushi Kumar, B.

2017-11-01

The main purpose of this work is to investigate the diffusion-thermo effects on unsteady combined convection magneto-hydromagnetic boundary layer flow of viscous electrically conducting and chemically reacting fluid over a vertical permeable radiated plate embedded in a highly porous medium. The slip flow regime is applied at the porous interface a uniform magnetic field is applied normal to the fluid flow direction which absorbs the fluid with suction that varies with time. The dimensionless governing equations are solved analytically using two terms harmonic and non-harmonic functions. The expressions for the fields of velocity, temperature and concentration are obtained. For engineering interest we also calculated the physical quantities the skin friction coefficient, Nusselt and Sherwood number are derived. The effects of various physical parameters on the flow quantities are studied through graphs and tables. For the validity, we have checked our results with previously published work and found good agreement with already existing studies.

Strength and acoustic properties of Ottawa sand containing laboratory-formed methane gas hydrate

USGS Publications Warehouse

Winters, William J.; Waite, William F.; Mason, David H.

2004-01-01

Although gas hydrate occurs in a wide variety of sediment types and is present and even pervasive at some locations on continental margins, little is known about how it forms naturally. Physical properties of the resultant gas hydrate-sediment mixtures, data needed for input into models that predict location and quantity of in situ hydrate are also lacking. Not only do properties of the host materials influence the type and quantity of hydrate formed and whether a particular deposit may be an economic resource or a geohazard, the properties of the natural sediment are also subsequently changed by the formation of gas hydrate in the pore space. The magnitude of the change is primarily related to the amount and the weighted inter-particle distribution of the hydrate deposits in relation to the actual sediment grains. Our goal is to understand the interaction between natural sediments and gas hydrate formation in order to quantify physical properties that are useful to predictive models.

Difference in quantity discrimination in dogs and wolves

PubMed Central

Range, Friederike; Jenikejew, Julia; Schröder, Isabelle; Virányi, Zsófia

2014-01-01

Certain aspects of social life, such as engaging in intergroup conflicts, as well as challenges posed by the physical environment, may facilitate the evolution of quantity discrimination. In lack of excessive comparative data, one can only hypothesize about its evolutionary origins, but human-raised wolves performed well when they had to choose the larger of two sets of 1–4 food items that had been sequentially placed into two opaque cans. Since in such paradigms, the animals never see the entire content of either can, their decisions are thought to rely on mental representation of the two quantities rather than on some perceptual factors such as the overall volume or surface area of the two amounts. By equaling the time that it takes to enter each quantity into the cans or the number of items entered, one can further rule out the possibility that animals simply choose based on the amount of time needed to present the two quantities. While the wolves performed well even in such a control condition, dogs failed to choose the larger one of two invisible quantities in another study using a similar paradigm. Because this disparity could be explained by procedural differences, in the current study, we set out to test dogs that were raised and kept identically as the previously tested wolves using the same set-up and procedure. Our results confirm the former finding that dogs, in comparison to wolves, have inferior skills to represent quantities mentally. This seems to be in line with Frank’s (1980) hypothesis suggesting that domestication altered the information processing of dogs. However, as discussed, also alternative explanations may exist. PMID:25477834

Enhanced Verification Test Suite for Physics Simulation Codes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kamm, J R; Brock, J S; Brandon, S T

2008-10-10

This document discusses problems with which to augment, in quantity and in quality, the existing tri-laboratory suite of verification problems used by Los Alamos National Laboratory (LANL), Lawrence Livermore National Laboratory (LLNL), and Sandia National Laboratories (SNL). The purpose of verification analysis is demonstrate whether the numerical results of the discretization algorithms in physics and engineering simulation codes provide correct solutions of the corresponding continuum equations. The key points of this document are: (1) Verification deals with mathematical correctness of the numerical algorithms in a code, while validation deals with physical correctness of a simulation in a regime of interest.more » This document is about verification. (2) The current seven-problem Tri-Laboratory Verification Test Suite, which has been used for approximately five years at the DOE WP laboratories, is limited. (3) Both the methodology for and technology used in verification analysis have evolved and been improved since the original test suite was proposed. (4) The proposed test problems are in three basic areas: (a) Hydrodynamics; (b) Transport processes; and (c) Dynamic strength-of-materials. (5) For several of the proposed problems we provide a 'strong sense verification benchmark', consisting of (i) a clear mathematical statement of the problem with sufficient information to run a computer simulation, (ii) an explanation of how the code result and benchmark solution are to be evaluated, and (iii) a description of the acceptance criterion for simulation code results. (6) It is proposed that the set of verification test problems with which any particular code be evaluated include some of the problems described in this document. Analysis of the proposed verification test problems constitutes part of a necessary--but not sufficient--step that builds confidence in physics and engineering simulation codes. More complicated test cases, including physics models of greater sophistication or other physics regimes (e.g., energetic material response, magneto-hydrodynamics), would represent a scientifically desirable complement to the fundamental test cases discussed in this report. The authors believe that this document can be used to enhance the verification analyses undertaken at the DOE WP Laboratories and, thus, to improve the quality, credibility, and usefulness of the simulation codes that are analyzed with these problems.« less

Responding to increased needs and demands for water

Treesearch

Hans M. Gregersen; William K. Easter; J. Edward de Steiguer

2000-01-01

The nature of the increased needs and demands for water relate to water quantity and quality, bringing in the dimensions of timing and location of water flows. Some key past international activities related to water and watershed policy are reviewed. The common threads that are shaping likely future responses relate to technical vs. institutional means of addressing...

Forest environmental investments and implications for climate change mitigation.

Treesearch

Ralph J. Alig; Lucas S. Bair

2006-01-01

Forest environmental conditions are affected by climate change, but investments in forest environmental quality can be used as part of the climate change mitigation strategy. A key question involving the potential use of forests to store more carbon as part of climate change mitigation is the impact of forest investments on the timing and quantity of forest volumes...

Creating a Seamless Web of Services for Youth: The DC Children and Youth Investment Partnership.

ERIC Educational Resources Information Center

Keegan, Sinead; Chaplin, Duncan

This report describes the DC Children and Youth Investment Partnership, which helps improve outcomes for DC youth by building a sustainable partnership to increase the quality and quantity of youth services. Data from interviews with key actors, attendance at Partnership meetings, and site visits with affiliated initiatives show progress in…

The influence of fuels treatment and landscape arrangement on simulated fire behavior, southern Cascade Range, California

Treesearch

David A. Schmidt; Alan H. Taylor; Carl N. Skinner

2008-01-01

Wildfire behavior can be modified by altering the quantity, structure, and arrangement of fuel (flammable vegetation) by silvicultural treatments such as forest thinning and prescribed burning. The type and arrangement (including landscape location) of treated areas have been demonstrated to influence wildfire behavior. This study analyzes the response of several key...

Soil water dynamics and nitrate leaching under corn-soybean rotation, continuous corn, and kura clover

USDA-ARS?s Scientific Manuscript database

Improving the water quantity and water quality impacts of corn (Zea mays L.)- and soybean (Glycine max L.)-based cropping systems is a key challenge for agriculture in the US Midwest and similar regions around the world. Long-term field experiments are important for documenting those effects and exp...

Matter under extreme conditions experiments at the Linac Coherent Light Source

DOE PAGES

Glenzer, S. H.; Fletcher, L. B.; Galtier, E.; ...

2015-12-10

The Matter in Extreme Conditions end station at the Linac Coherent Light Source (LCLS) is a new tool enabling accurate pump-probe measurements for studying the physical properties of matter in the high-energy density physics regime. This instrument combines the world’s brightest x-ray source, the LCLS x-ray beam, with high-power lasers consisting of two nanosecond Nd:glass laser beams and one short-pulse Ti:sapphire laser. These lasers produce short-lived states of matter with high pressures, high temperatures or high densities with properties that are important for applications in nuclear fusion research, laboratory astrophysics and the development of intense radiation sources. In the firstmore » experiments, we have performed highly accurate x-ray diffraction and x-ray Thomson scattering techniques on shock-compressed matter resolving the transition from compressed solid matter to a co-existence regime and into the warm dense matter state. Furthermore, these complex charged-particle systems are dominated by strong correlations and quantum effects. They exist in planetary interiors and laboratory experiments, e.g., during high-power laser interactions with solids or the compression phase of inertial confinement fusion implosions. Applying record peak brightness X rays resolves the ionic interactions at atomic (Ångstrom) scale lengths and measure the static structure factor, which is a key quantity for determining equation of state data and important transport coefficients. Simultaneously, spectrally resolved measurements of plasmon features provide dynamic structure factor information that yield temperature and density with unprecedented precision at micron-scale resolution in dynamic compression experiments. This set of studies demonstrates our ability to measure fundamental thermodynamic properties that determine the state of matter in the high-energy density physics regime.« less

A Comparison of the Red Green Blue (RGB) Air Mass Imagery and Hyperspectral Infrared Retrieved Profiles and NOAA G-IV Dropsondes

NASA Technical Reports Server (NTRS)

Berndt, Emily; Folmer, Michael; Dunion, Jason

2014-01-01

RGB air mass imagery is derived from multiple channels or paired channel differences. The combination of channels and channel differences means the resulting imagery does not represent a quantity or physical parameter such as brightness temperature in conventional single channel imagery. Without a specific quantity to reference, forecasters are often confused as to what RGB products represent. Hyperspectral infrared retrieved profiles and NOAA G-IV dropsondes provide insight about the vertical structure of the air mass represented on the RGB air mass imagery and are a first step to validating the imagery.

Measuring effective temperatures in a generalized Gibbs ensemble

NASA Astrophysics Data System (ADS)

Foini, Laura; Gambassi, Andrea; Konik, Robert; Cugliandolo, Leticia F.

2017-05-01

The local physical properties of an isolated quantum statistical system in the stationary state reached long after a quench are generically described by the Gibbs ensemble, which involves only its Hamiltonian and the temperature as a parameter. If the system is instead integrable, additional quantities conserved by the dynamics intervene in the description of the stationary state. The resulting generalized Gibbs ensemble involves a number of temperature-like parameters, the determination of which is practically difficult. Here we argue that in a number of simple models these parameters can be effectively determined by using fluctuation-dissipation relationships between response and correlation functions of natural observables, quantities which are accessible in experiments.

Features of sound propagation through and stability of a finite shear layer

NASA Technical Reports Server (NTRS)

Koutsoyannis, S. P.

1977-01-01

The plane wave propagation, the stability, and the rectangular duct mode problems of a compressible, inviscid, linearly sheared, parallel, homogeneous flow are shown to be governed by Whittaker's equation. The exact solutions for the perturbation quantities are essentially the Whittaker M-functions where the nondimensional quantities have precise physical meanings. A number of known results are obtained as limiting cases of the exact solutions. For the compressible finite thickness shear layer it is shown that no resonances and no critical angles exist for all Mach numbers, frequencies, and shear layer velocity profile slopes except in the singular case of the vortex sheet.

Ageing and endurance training effects on quantity and quality of pulmonary vascular bed in healthy men

PubMed Central

2014-01-01

It has recently been demonstrated that in healthy individuals, peak oxygen consumption is associated with a greater pulmonary capillary blood volume and a more distensible pulmonary circulation. Our cross-sectional study suggests that, in healthy men aged 20 to 60 years (n = 63), endurance sport practice (vigorous-intensity domain of the International Physical Activity Questionnaire) is associated with better quantity (pulmonary capillary blood volume) and quality (slope of increase in lung diffusion for carbon monoxide on exercise) of the pulmonary vascular bed, partly counterbalancing the deleterious effects of ageing, which remains to be demonstrated in a prospective longitudinal design. PMID:24460636

2013 Wind Technologies Market Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wiser, R.; Bolinger, M.; Barbose, G.

2014-08-01

This annual report provides a detailed overview of developments and trends in the U.S. wind power market, with a particular focus on 2013. This 2013 edition updates data presented in previous editions while highlighting key trends and important new developments. The report includes an overview of key installation-related trends; trends in wind power capacity growth; how that growth compares to other countries and generation sources; the amount and percentage of wind energy in individual states; the status of offshore wind power development and the quantity of proposed wind power capacity in various interconnection queues in the United States.

The Role of Self-Efficacy and Friend Support on Adolescent Vigorous Physical Activity

ERIC Educational Resources Information Center

Hamilton, Kyra; Warner, Lisa M.; Schwarzer, Ralf

2017-01-01

Objectives: Physical activity, including some form of vigorous activity, is a key component of a healthy lifestyle in young people. Self-efficacy and social support have been identified as key determinants of physical activity; however, the mechanism that reflects the interplay of these two factors is not well understood. The aim of the current…

Apar-T: code, validation, and physical interpretation of particle-in-cell results

NASA Astrophysics Data System (ADS)

Melzani, Mickaël; Winisdoerffer, Christophe; Walder, Rolf; Folini, Doris; Favre, Jean M.; Krastanov, Stefan; Messmer, Peter

2013-10-01

We present the parallel particle-in-cell (PIC) code Apar-T and, more importantly, address the fundamental question of the relations between the PIC model, the Vlasov-Maxwell theory, and real plasmas. First, we present four validation tests: spectra from simulations of thermal plasmas, linear growth rates of the relativistic tearing instability and of the filamentation instability, and nonlinear filamentation merging phase. For the filamentation instability we show that the effective growth rates measured on the total energy can differ by more than 50% from the linear cold predictions and from the fastest modes of the simulation. We link these discrepancies to the superparticle number per cell and to the level of field fluctuations. Second, we detail a new method for initial loading of Maxwell-Jüttner particle distributions with relativistic bulk velocity and relativistic temperature, and explain why the traditional method with individual particle boosting fails. The formulation of the relativistic Harris equilibrium is generalized to arbitrary temperature and mass ratios. Both are required for the tearing instability setup. Third, we turn to the key point of this paper and scrutinize the question of what description of (weakly coupled) physical plasmas is obtained by PIC models. These models rely on two building blocks: coarse-graining, i.e., grouping of the order of p ~ 1010 real particles into a single computer superparticle, and field storage on a grid with its subsequent finite superparticle size. We introduce the notion of coarse-graining dependent quantities, i.e., quantities depending on p. They derive from the PIC plasma parameter ΛPIC, which we show to behave as ΛPIC ∝ 1/p. We explore two important implications. One is that PIC collision- and fluctuation-induced thermalization times are expected to scale with the number of superparticles per grid cell, and thus to be a factor p ~ 1010 smaller than in real plasmas, a fact that we confirm with simulations. The other is that the level of electric field fluctuations scales as 1/ΛPIC ∝ p. We provide a corresponding exact expression, taking into account the finite superparticle size. We confirm both expectations with simulations. Fourth, we compare the Vlasov-Maxwell theory, often used for code benchmarking, to the PIC model. The former describes a phase-space fluid with Λ = + ∞ and no correlations, while the PIC plasma features a small Λ and a high level of correlations when compared to a real plasma. These differences have to be kept in mind when interpreting and validating PIC results against the Vlasov-Maxwell theory and when modeling real physical plasmas.

10 CFR 73.20 - General performance objective and requirements.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 10 Energy 2 2012-01-01 2012-01-01 false General performance objective and requirements. 73.20 Section 73.20 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) PHYSICAL PROTECTION OF PLANTS AND MATERIALS... special nuclear material; takes delivery of formula quantities of strategic special nuclear material free...

10 CFR 73.20 - General performance objective and requirements.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 10 Energy 2 2014-01-01 2014-01-01 false General performance objective and requirements. 73.20 Section 73.20 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) PHYSICAL PROTECTION OF PLANTS AND MATERIALS... special nuclear material; takes delivery of formula quantities of strategic special nuclear material free...

10 CFR 73.20 - General performance objective and requirements.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 10 Energy 2 2013-01-01 2013-01-01 false General performance objective and requirements. 73.20 Section 73.20 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) PHYSICAL PROTECTION OF PLANTS AND MATERIALS... special nuclear material; takes delivery of formula quantities of strategic special nuclear material free...

10 CFR 73.20 - General performance objective and requirements.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 10 Energy 2 2011-01-01 2011-01-01 false General performance objective and requirements. 73.20 Section 73.20 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) PHYSICAL PROTECTION OF PLANTS AND MATERIALS... special nuclear material; takes delivery of formula quantities of strategic special nuclear material free...

49 CFR 240.409 - Hearings.

Code of Federal Regulations, 2012 CFR

2012-10-01

... be transcribed and made a part of the record. Any physical evidence or written argument received or... is a genuine dispute. (d) The presiding officer may authorize discovery of the types and quantities... limitations as to the presentation of evidence and issues, for any party's willful failure or refusal to...

49 CFR 240.409 - Hearings.

Code of Federal Regulations, 2013 CFR

2013-10-01

... be transcribed and made a part of the record. Any physical evidence or written argument received or... is a genuine dispute. (d) The presiding officer may authorize discovery of the types and quantities... limitations as to the presentation of evidence and issues, for any party's willful failure or refusal to...

49 CFR 240.409 - Hearings.

Code of Federal Regulations, 2014 CFR

2014-10-01

... be transcribed and made a part of the record. Any physical evidence or written argument received or... is a genuine dispute. (d) The presiding officer may authorize discovery of the types and quantities... limitations as to the presentation of evidence and issues, for any party's willful failure or refusal to...

EduXs: Multilayer Educational Services Platforms

ERIC Educational Resources Information Center

Chang, Li-Jie; Yang, Jie-Chi; Deng, Yi-Chan; Chan, Tak-Wai

2003-01-01

How to use the online social learning communities to improve quality and quantity of interactions in physical social learning communities is an important issue. This work describes the design and implementation of multilayer educational services platforms that enable learners to establish their own online social learning communities and integrate…

29 CFR 779.405 - Statutory provisions.

Code of Federal Regulations, 2010 CFR

2010-07-01

... character operating in the community or the nearest comparable community. Before the Secretary may issue a... * * * whose earning or productive capacity is impaired by age or physical or mental deficiency or injury, at... in the vicinity for essentially the same type, quality, and quantity of work. (2) The Secretary...

10 CFR 40.13 - Unimportant quantities of source material.

Code of Federal Regulations, 2011 CFR

2011-01-01

... receives, possesses, uses, transfers or delivers source material in any chemical mixture, compound... commercially manufactured glass brick, pane glass, ceramic tile, or other glass or ceramic used in construction... authorize the chemical, physical or metallurgical treatment or processing of any such product or part; and...

INNOVATIVE, IN SITU TREATMENT OF ACID MINE DRAINAGE USING SULFATE REDUCING BACTERIA

EPA Science Inventory

Acid generation in abandoned mines is a widespread problem. There are a numberous quantity of abandoned mines in the west which have no power source, have limited physical accessibility and have limited remediation funds available. Acid is produced chemically, through pyritic min...

How do I convert the numbers stored in the files to physical quantities?

Atmospheric Science Data Center

2014-12-08

At Level 1A, the 14 most significant bits (MSB) directly represent the raw digital count from the camera's Charge-Coupled Device (CCD). The 2 least significant bits (LSB) of the 16-bit data values are data quality indicators (DQI). A...

10 CFR 37.31 - Protection of information.

Code of Federal Regulations, 2014 CFR

2014-01-01

... verifies information such as name, date of birth, social security number, gender, and other applicable... 10 Energy 1 2014-01-01 2014-01-01 false Protection of information. 37.31 Section 37.31 Energy NUCLEAR REGULATORY COMMISSION PHYSICAL PROTECTION OF CATEGORY 1 AND CATEGORY 2 QUANTITIES OF RADIOACTIVE...

Helium tables.

NASA Technical Reports Server (NTRS)

Havill, Clinton H

1928-01-01

These tables are intended to provide a standard method and to facilitate the calculation of the quantity of "Standard Helium" in high pressure containers. The research data and the formulas used in the preparation of the tables were furnished by the Research Laboratory of Physical Chemistry, of the Massachusetts Institute of Technology.

Green Space Visits among Adolescents: Frequency and Predictors in the PIAMA Birth Cohort Study.

PubMed

Bloemsma, Lizan D; Gehring, Ulrike; Klompmaker, Jochem O; Hoek, Gerard; Janssen, Nicole A H; Smit, Henriëtte A; Vonk, Judith M; Brunekreef, Bert; Lebret, Erik; Wijga, Alet H

2018-04-30

Green space may influence health through several pathways, for example, increased physical activity, enhanced social cohesion, reduced stress, and improved air quality. For green space to increase physical activity and social cohesion, spending time in green spaces is likely to be important. We examined whether adolescents visit green spaces and for what purposes. Furthermore, we assessed the predictors of green space visits. In this cross-sectional study, data for 1911 participants of the Dutch PIAMA (Prevention and Incidence of Asthma and Mite Allergy) birth cohort were analyzed. At age 17, adolescents reported how often they visited green spaces for physical activities, social activities, relaxation, and to experience nature and quietness. We assessed the predictors of green space visits altogether and for different purposes by log-binomial regression. Fifty-three percent of the adolescents visited green spaces at least once a week in summer, mostly for physical and social activities. Adolescents reporting that a green environment was (very) important to them visited green spaces most frequently {adjusted prevalence ratio (PR) [95% confidence interval (CI)] very vs. not important: 6.84 (5.10, 9.17) for physical activities and 4.76 (3.72, 6.09) for social activities}. Boys and adolescents with highly educated fathers visited green spaces more often for physical and social activities. Adolescents who own a dog visited green spaces more often to experience nature and quietness. Green space visits were not associated with the objectively measured quantity of residential green space, i.e., the average normalized difference vegetation index (NDVI) and percentages of urban, agricultural, and natural green space in circular buffers around the adolescents' homes. Subjective variables are stronger predictors of green space visits in adolescents than the objectively measured quantity of residential green space. https://doi.org/10.1289/EHP2429.

Cognition versus Constitution of Objects: From Kant to Modern Physics

NASA Astrophysics Data System (ADS)

Mittelstaedt, Peter

2009-07-01

Classical mechanics in phase space as well as quantum mechanics in Hilbert space lead to states and observables but not to objects that may be considered as carriers of observable quantities. However, in both cases objects can be constituted as new entities by means of invariance properties of the theories in question. We show, that this way of reasoning has a long history in physics and philosophy and that it can be traced back to the transcendental arguments in Kant’s critique of pure reason.

Structure for identifying, locating and quantifying physical phenomena

DOEpatents

Richardson, John G.

2006-10-24

A method and system for detecting, locating and quantifying a physical phenomena such as strain or a deformation in a structure. A minimum resolvable distance along the structure is selected and a quantity of laterally adjacent conductors is determined. Each conductor includes a plurality of segments coupled in series which define the minimum resolvable distance along the structure. When a deformation occurs, changes in the defined energy transmission characteristics along each conductor are compared to determine which segment contains the deformation.

Method and apparatus for identifying, locating and quantifying physical phenomena and structure including same

DOEpatents

Richardson, John G.

2006-01-24

A method and system for detecting, locating and quantifying a physical phenomena such as strain or a deformation in a structure. A minimum resolvable distance along the structure is selected and a quantity of laterally adjacent conductors is determined. Each conductor includes a plurality of segments coupled in series which define the minimum resolvable distance along the structure. When a deformation occurs, changes in the defined energy transmission characteristics along each conductor are compared to determine which segment contains the deformation.

An introduction to the physical aspects of helicopter stability

NASA Technical Reports Server (NTRS)

Gessow, Alfred; Amer, Kenneth B

1950-01-01

In order to provide engineers interested in rotating-wing aircraft, but with no specialized training in stability theory, some understanding of the factors that influence the flying qualities of the helicopter, an explanation is made of both the static stability and the stick-fixed oscillation in hovering and forward flight in terms of fundamental physical quantities. Three significant stability factors -- static stability with angle of attack, static stability with speed, and damping due to a pitching or rolling velocity -- are explained in detail.

[From microdosimetry to nanodosimetry--the link between radiobiology and radiation physics].

PubMed

Fu, Yuchuan; Li, Ping

2014-06-01

The link between micro- and macro-parameters for radiation interactions that take place in living biological systems is described in this paper. Meanwhile recent progress and development in microdosimetry and nanodosimetry are introduced, including the methods to measure and calculate these micro- or nano-parameters. The relationship between radiobiology and physical quantities in microdosimetry and nanodosimetry was presented. Both the current problems on their applications in radiation protection and radiotherapy and the future development direction are proposed.

Magnetic nanoparticles: preparation, physical properties, and applications in biomedicine

PubMed Central

2012-01-01

Finally, we have addressed some relevant findings on the importance of having well-defined synthetic strategies developed for the generation of MNPs, with a focus on particle formation mechanism and recent modifications made on the preparation of monodisperse samples of relatively large quantities not only with similar physical features, but also with similar crystallochemical characteristics. Then, different methodologies for the functionalization of the prepared MNPs together with the characterization techniques are explained. Theorical views on the magnetism of nanoparticles are considered. PMID:22348683

Ensemble-type numerical uncertainty information from single model integrations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rauser, Florian, E-mail: florian.rauser@mpimet.mpg.de; Marotzke, Jochem; Korn, Peter

2015-07-01

We suggest an algorithm that quantifies the discretization error of time-dependent physical quantities of interest (goals) for numerical models of geophysical fluid dynamics. The goal discretization error is estimated using a sum of weighted local discretization errors. The key feature of our algorithm is that these local discretization errors are interpreted as realizations of a random process. The random process is determined by the model and the flow state. From a class of local error random processes we select a suitable specific random process by integrating the model over a short time interval at different resolutions. The weights of themore » influences of the local discretization errors on the goal are modeled as goal sensitivities, which are calculated via automatic differentiation. The integration of the weighted realizations of local error random processes yields a posterior ensemble of goal approximations from a single run of the numerical model. From the posterior ensemble we derive the uncertainty information of the goal discretization error. This algorithm bypasses the requirement of detailed knowledge about the models discretization to generate numerical error estimates. The algorithm is evaluated for the spherical shallow-water equations. For two standard test cases we successfully estimate the error of regional potential energy, track its evolution, and compare it to standard ensemble techniques. The posterior ensemble shares linear-error-growth properties with ensembles of multiple model integrations when comparably perturbed. The posterior ensemble numerical error estimates are of comparable size as those of a stochastic physics ensemble.« less

The host galaxy of a fast radio burst.

PubMed

Keane, E F; Johnston, S; Bhandari, S; Barr, E; Bhat, N D R; Burgay, M; Caleb, M; Flynn, C; Jameson, A; Kramer, M; Petroff, E; Possenti, A; van Straten, W; Bailes, M; Burke-Spolaor, S; Eatough, R P; Stappers, B W; Totani, T; Honma, M; Furusawa, H; Hattori, T; Morokuma, T; Niino, Y; Sugai, H; Terai, T; Tominaga, N; Yamasaki, S; Yasuda, N; Allen, R; Cooke, J; Jencson, J; Kasliwal, M M; Kaplan, D L; Tingay, S J; Williams, A; Wayth, R; Chandra, P; Perrodin, D; Berezina, M; Mickaliger, M; Bassa, C

2016-02-25

In recent years, millisecond-duration radio signals originating in distant galaxies appear to have been discovered in the so-called fast radio bursts. These signals are dispersed according to a precise physical law and this dispersion is a key observable quantity, which, in tandem with a redshift measurement, can be used for fundamental physical investigations. Every fast radio burst has a dispersion measurement, but none before now have had a redshift measurement, because of the difficulty in pinpointing their celestial coordinates. Here we report the discovery of a fast radio burst and the identification of a fading radio transient lasting ~6 days after the event, which we use to identify the host galaxy; we measure the galaxy's redshift to be z = 0.492 ± 0.008. The dispersion measure and redshift, in combination, provide a direct measurement of the cosmic density of ionized baryons in the intergalactic medium of ΩIGM = 4.9 ± 1.3 per cent, in agreement with the expectation from the Wilkinson Microwave Anisotropy Probe, and including all of the so-called 'missing baryons'. The ~6-day radio transient is largely consistent with the radio afterglow of a short γ-ray burst, and its existence and timescale do not support progenitor models such as giant pulses from pulsars, and supernovae. This contrasts with the interpretation of another recently discovered fast radio burst, suggesting that there are at least two classes of bursts.

The Physics and Diagnostic Potential of Ultraviolet Spectropolarimetry

NASA Astrophysics Data System (ADS)

Trujillo Bueno, Javier; Landi Degl'Innocenti, Egidio; Belluzzi, Luca

2017-09-01

The empirical investigation of the magnetic field in the outer solar atmosphere is a very important challenge in astrophysics. To this end, we need to identify, measure and interpret observable quantities sensitive to the magnetism of the upper chromosphere, transition region and corona. This paper provides an overview of the physics and diagnostic potential of spectropolarimetry in permitted spectral lines of the ultraviolet solar spectrum, such as the Mg ii h and k lines around 2800 Å, the hydrogen Lyman-α line at 1216 Å, and the Lyman-α line of He ii at 304 Å. The outer solar atmosphere is an optically pumped vapor and the linear polarization of such spectral lines is dominated by the atomic level polarization produced by the absorption and scattering of anisotropic radiation. Its modification by the action of the Hanle and Zeeman effects in the inhomogeneous and dynamic solar atmosphere needs to be carefully understood because it encodes the magnetic field information. The circular polarization induced by the Zeeman effect in some ultraviolet lines (e.g., Mg ii h & k) is also of diagnostic interest, especially for probing the outer solar atmosphere in plages and more active regions. The few (pioneering) observational attempts carried out so far to measure the ultraviolet spectral line polarization produced by optically pumped atoms in the upper chromosphere, transition region and corona are also discussed. We emphasize that ultraviolet spectropolarimetry is a key gateway to the outer atmosphere of the Sun and of other stars.

Empirical Temperature Measurement in Protoplanetary Disks

NASA Astrophysics Data System (ADS)

Weaver, Erik; Isella, Andrea; Boehler, Yann

2018-02-01

The accurate measurement of temperature in protoplanetary disks is critical to understanding many key features of disk evolution and planet formation, from disk chemistry and dynamics, to planetesimal formation. This paper explores the techniques available to determine temperatures from observations of single, optically thick molecular emission lines. Specific attention is given to issues such as the inclusion of optically thin emission, problems resulting from continuum subtraction, and complications of real observations. Effort is also made to detail the exact nature and morphology of the region emitting a given line. To properly study and quantify these effects, this paper considers a range of disk models, from simple pedagogical models to very detailed models including full radiative transfer. Finally, we show how the use of the wrong methods can lead to potentially severe misinterpretations of data, leading to incorrect measurements of disk temperature profiles. We show that the best way to estimate the temperature of emitting gas is to analyze the line peak emission map without subtracting continuum emission. Continuum subtraction, which is commonly applied to observations of line emission, systematically leads to underestimation of the gas temperature. We further show that once observational effects such as beam dilution and noise are accounted for, the line brightness temperature derived from the peak emission is reliably within 10%–15% of the physical temperature of the emitting region, assuming optically thick emission. The methodology described in this paper will be applied in future works to constrain the temperature, and related physical quantities, in protoplanetary disks observed with ALMA.

The diagnostic capability of iron limes

NASA Astrophysics Data System (ADS)

Giannini, Teresa; Nisini, Brunella; Antoniucci, Simone; Alcala, Juan; Bacciotti, Francesca; Bonito, Rosaria; Podio, Linda; Stelzer, Beate; Whelan, Emma

2013-07-01

We present the VLT/X-Shooter spectrum of two jets from young protostars of different luminosity and mass, ESO-Halpha 574 and Par-Lup 3-4. In the covered spectral range (350-2500 nm) we detected more than 100 [FeII] and [FeIII] lines, which are used to precisely probe the key physical parameters of the gas (electron density and temperature, ionization degree, visual extinction). These quantities have been compared with shock-model predictions, which suggest that only the higher luminosity source (ESO-Ha 574) is able to drive a high-velocity and dissociative shock. The diagnostic capability of Iron, proven on the presented objects, represents a unique tool for the following reasons: 1) the large number of lines in the uv-infrared range makes possible to trace the physical conditions in a very large range of the parameter space; 2) at variance with the diagnostic commonly performed with other species, such as Oxygen, Nitrogen, and Sulphur, no assumption on the relative abundance is needed, since all the parameters are derived from line ratios of the same species; 3) in the unperturbed ISM, Iron is locked on the grain surfaces, while it is released in gas-phase if gas-grain or grain-grain collisions occur within a shock. Therefore the Iron abundance (derivable from ratios of Iron lines with those of other volatile species) is a direct probe of the presence of dust in the jet beam, an information crucial to understand whether jets originate close to the star or in the circumstellar disk.

Evaluating the Effect of Three Water Management Techniques on Tomato Crop.

PubMed

Elnesr, Mohammad Nabil; Alazba, Abdurrahman Ali; Zein El-Abedein, Assem Ibrahim; El-Adl, Mahmoud Maher

2015-01-01

The effects of three water management techniques were evaluated on subsurface drip irrigated tomatoes. The three techniques were the intermittent flow (3 pulses), the dual-lateral drip system (two lateral lines per row, at 15 and 25 cm below soil surface), and the physical barrier (buried at 30 cm below soil surface). Field experiments were established for two successive seasons. Water movement in soil was monitored using continuously logging capacitance probes up to 60 cm depth. The results showed that the dual lateral technique positively increased the yield up to 50%, water use efficiency up to 54%, while the intermittent application improved some of the quality measures (fruit size, TSS, and Vitamin C), not the quantity of the yield that decreased in one season, and not affected in the other. The physical barrier has no significant effect on any of the important growth measures. The soil water patterns showed that the dual lateral method lead to uniform wetting pattern with depth up to 45 cm, the physical barrier appeared to increase lateral and upward water movement, while the intermittent application kept the wetting pattern at higher moisture level for longer time. The cost analysis showed also that the economic treatments were the dual lateral followed by the intermittent technique, while the physical barrier is not economical. The study recommends researching the effect of the dual lateral method on the root growth and performance. The intermittent application may be recommended to improve tomato quality but not quantity. The physical barrier is not recommended unless in high permeable soils.

Reliability of 3D laser-based anthropometry and comparison with classical anthropometry.

PubMed

Kuehnapfel, Andreas; Ahnert, Peter; Loeffler, Markus; Broda, Anja; Scholz, Markus

2016-05-26

Anthropometric quantities are widely used in epidemiologic research as possible confounders, risk factors, or outcomes. 3D laser-based body scans (BS) allow evaluation of dozens of quantities in short time with minimal physical contact between observers and probands. The aim of this study was to compare BS with classical manual anthropometric (CA) assessments with respect to feasibility, reliability, and validity. We performed a study on 108 individuals with multiple measurements of BS and CA to estimate intra- and inter-rater reliabilities for both. We suggested BS equivalents of CA measurements and determined validity of BS considering CA the gold standard. Throughout the study, the overall concordance correlation coefficient (OCCC) was chosen as indicator of agreement. BS was slightly more time consuming but better accepted than CA. For CA, OCCCs for intra- and inter-rater reliability were greater than 0.8 for all nine quantities studied. For BS, 9 of 154 quantities showed reliabilities below 0.7. BS proxies for CA measurements showed good agreement (minimum OCCC > 0.77) after offset correction. Thigh length showed higher reliability in BS while upper arm length showed higher reliability in CA. Except for these issues, reliabilities of CA measurements and their BS equivalents were comparable.

Field Extension of Real Values of Physical Observables in Classical Theory can Help Attain Quantum Results

NASA Astrophysics Data System (ADS)

Wang, Hai; Kumar, Asutosh; Cho, Minhyung; Wu, Junde

2018-04-01

Physical quantities are assumed to take real values, which stems from the fact that an usual measuring instrument that measures a physical observable always yields a real number. Here we consider the question of what would happen if physical observables are allowed to assume complex values. In this paper, we show that by allowing observables in the Bell inequality to take complex values, a classical physical theory can actually get the same upper bound of the Bell expression as quantum theory. Also, by extending the real field to the quaternionic field, we can puzzle out the GHZ problem using local hidden variable model. Furthermore, we try to build a new type of hidden-variable theory of a single qubit based on the result.

Critical Analysis of the Mathematical Formalism of Theoretical Physics. II. Foundations of Vector Calculus

NASA Astrophysics Data System (ADS)

Kalanov, Temur Z.

2014-03-01

A critical analysis of the foundations of standard vector calculus is proposed. The methodological basis of the analysis is the unity of formal logic and of rational dialectics. It is proved that the vector calculus is incorrect theory because: (a) it is not based on a correct methodological basis - the unity of formal logic and of rational dialectics; (b) it does not contain the correct definitions of ``movement,'' ``direction'' and ``vector'' (c) it does not take into consideration the dimensions of physical quantities (i.e., number names, denominate numbers, concrete numbers), characterizing the concept of ''physical vector,'' and, therefore, it has no natural-scientific meaning; (d) operations on ``physical vectors'' and the vector calculus propositions relating to the ''physical vectors'' are contrary to formal logic.

Factor Analysis of Key Success Indicators in Curriculum Quality Assurance Operation for Bachelor's Degree in Physical Education

ERIC Educational Resources Information Center

Sukdee, Thitipong; Tornee, Songpol; Kraipetch, Chanita

2017-01-01

The purpose of this study was to analyze the factors of key success indicators in curriculum quality assurance operation for bachelor's degree in Physical Education. The 576 subjects were selected using cluster sampling from curriculum lecturers, staffs, and lecturers at the Academy of Physical Education Curriculum. The instrument was a related…

Opportunity Cost and the Intelligence of Economists: A Comment

ERIC Educational Resources Information Center

Arce, Daniel G.

2016-01-01

In "Opportunity Cost: A Reexamination," Professor Parkin contrasts forgone physical quantities with forgone values as measures of the opportunity cost of basic economic decisions. The impetus for his study stems from an experiment conducted by Ferraro and Taylor (2005), in which professional economists could not reach a consensus over…

Tools for Scientific Thinking: Microcomputer-Based Laboratories for the Naive Science Learner.

ERIC Educational Resources Information Center

Thornton, Ronald K.

A promising new development in science education is the use of microcomputer-based laboratory tools that allow for student-directed data acquisition, display, and analysis. Microcomputer-based laboratories (MBL) make use of inexpensive microcomputer-connected probes to measure such physical quantities as temperature, position, and various…

An Investigation of the Impact of Manipulative Type and Instructional Guidance on Preschoolers' Symbolic Development of Quantities

ERIC Educational Resources Information Center

Carbonneau, Kira J.

2013-01-01

Activity-based instructional strategies promote physical interaction with manipulatives to represent abstract concepts. As a means to improve student achievement in mathematics, educational researchers and practitioners often recommend instructional strategies that capitalize on the assumed benefits of manipulatives. Recent research has indicated…

A New Twist on Torque Labs

ERIC Educational Resources Information Center

Lane, W. Brian

2014-01-01

The traditional introductory-level meterstick-balancing lab assumes that students already know what torque is and that they readily identify it as a physical quantity of interest. We propose a modified version of this activity in which students qualitatively and quantitatively measure the amount of force required to keep the meterstick level. The…

Linkages between forest soils and water quality and quantity

Treesearch

Daniel G. Neary; George G. Ice; C. Rhett Jackson

2009-01-01

The most sustainable and best quality fresh water sources in the world originate in forest ecosystems. The biological, chemical, and physical characteristics of forest soils are particularly well suited to delivering high quality water to streams, moderating stream hydrology, and providing diverse aquatic habitat. Forest soils feature litter layers and...

Master Planning School District Facility Needs

ERIC Educational Resources Information Center

Prager, Gary; Matschulat, Robert

2010-01-01

Most educational entities confront any number of facility issues. Upgrading the physical infrastructure to meet current and future demands can be intimidating. The quantity and magnitude of capital issues in a changing environment can be overwhelming. How can all this complexity be made coherent to assure that decisions are sound and limited…

Coupling fine-scale root and canopy structure using ground-based remote sensing

Treesearch

Brady Hardiman; Christopher Gough; John Butnor; Gil Bohrer; Matteo Detto; Peter Curtis

2017-01-01

Ecosystem physical structure, defined by the quantity and spatial distribution of biomass, influences a range of ecosystem functions. Remote sensing tools permit the non-destructive characterization of canopy and root features, potentially providing opportunities to link above- and belowground structure at fine spatial resolution in...

15 CFR 200.102 - Types of calibration and test services.

Code of Federal Regulations, 2012 CFR

2012-01-01

..., SERVICES, PROCEDURES, AND FEES § 200.102 Types of calibration and test services. (a) NIST has developed... and ranges of physical quantities are described in the NIST Special Publication 250 (SP 250). (See... years NIST has offered to the public new measurement services called measurement assurance programs...

15 CFR 200.102 - Types of calibration and test services.

Code of Federal Regulations, 2011 CFR

2011-01-01

..., SERVICES, PROCEDURES, AND FEES § 200.102 Types of calibration and test services. (a) NIST has developed... and ranges of physical quantities are described in the NIST Special Publication 250 (SP 250). (See... years NIST has offered to the public new measurement services called measurement assurance programs...

15 CFR 200.102 - Types of calibration and test services.

Code of Federal Regulations, 2014 CFR

2014-01-01

..., SERVICES, PROCEDURES, AND FEES § 200.102 Types of calibration and test services. (a) NIST has developed... and ranges of physical quantities are described in the NIST Special Publication 250 (SP 250). (See... years NIST has offered to the public new measurement services called measurement assurance programs...

15 CFR 200.102 - Types of calibration and test services.

Code of Federal Regulations, 2013 CFR

2013-01-01

..., SERVICES, PROCEDURES, AND FEES § 200.102 Types of calibration and test services. (a) NIST has developed... and ranges of physical quantities are described in the NIST Special Publication 250 (SP 250). (See... years NIST has offered to the public new measurement services called measurement assurance programs...

40 CFR 258.57 - Selection of remedy.

Code of Federal Regulations, 2014 CFR

2014-07-01

...-water quantity and quality; (iv) The potential damage to wildlife, crops, vegetation, and physical... MUNICIPAL SOLID WASTE LANDFILLS Ground-Water Monitoring and Corrective Action § 258.57 Selection of remedy... environment; (2) Attain the ground-water protection standard as specified pursuant to §§ 258.55 (h) or (i); (3...

40 CFR 258.57 - Selection of remedy.

Code of Federal Regulations, 2013 CFR

2013-07-01

...-water quantity and quality; (iv) The potential damage to wildlife, crops, vegetation, and physical... MUNICIPAL SOLID WASTE LANDFILLS Ground-Water Monitoring and Corrective Action § 258.57 Selection of remedy... environment; (2) Attain the ground-water protection standard as specified pursuant to §§ 258.55 (h) or (i); (3...

40 CFR 258.57 - Selection of remedy.

Code of Federal Regulations, 2012 CFR

2012-07-01

...-water quantity and quality; (iv) The potential damage to wildlife, crops, vegetation, and physical... MUNICIPAL SOLID WASTE LANDFILLS Ground-Water Monitoring and Corrective Action § 258.57 Selection of remedy... environment; (2) Attain the ground-water protection standard as specified pursuant to §§ 258.55 (h) or (i); (3...

The "critical limits for crystallinity" in nanoparticles of the elements: A combined thermodynamic and crystallographic critique

NASA Astrophysics Data System (ADS)

Pelegrina, J. L.; Guillermet, A. Fernández

2018-03-01

The theme of the present work is the procedure for evaluating the minimum size for the stability of a crystalline particle with respect to the same group of atoms but in the amorphous state. A key goal of the study is the critical analysis of an extensively quoted paper by F.G. Shi [J. Mater. Res. 9 (1994) 1307-1313], who presented a criterion for evaluating a "crystallinity distance" (h) through its relation with the "critical diameter" (dC) of a particle, i.e., the diameter below which no particles with the crystalline structure are expected to exist at finite temperatures. Key assumptions of Shi's model are a direct proportionality relation between h and dC , and a prescription for estimating h from crystallographic information. In the present work the accuracy of the Shi model is assessed with particular reference to nanoparticles of the elements. To this end, an alternative way to obtain h, that better realizes Shi's idea of this quantity as "the height of a monolayer of atoms on the bulk crystal surface", is explored. Moreover, a thermodynamic calculation of dC , which involves a description of the bulk- and the surface contributions to the crystalline/amorphous relative phase stability for nanoparticles, is performed. It is shown that the Shi equation does not account for the key features of the h vs. dC relation established in the current work. Consequently, it is concluded that the parameter h obtained only from information about the structure of the crystalline phase, does not provide an accurate route to estimate the quantity dC . In fact, a key result of the current study is that dC crucially depends on the relation between bulk- and surface contributions to the crystalline/amorphous relative thermodynamic stability.

Biased decoy-state measurement-device-independent quantum cryptographic conferencing with finite resources.

PubMed

Chen, RuiKe; Bao, WanSu; Zhou, Chun; Li, Hongwei; Wang, Yang; Bao, HaiZe

2016-03-21

In recent years, a large quantity of work have been done to narrow the gap between theory and practice in quantum key distribution (QKD). However, most of them are focus on two-party protocols. Very recently, Yao Fu et al proposed a measurement-device-independent quantum cryptographic conferencing (MDI-QCC) protocol and proved its security in the limit of infinitely long keys. As a step towards practical application for MDI-QCC, we design a biased decoy-state measurement-device-independent quantum cryptographic conferencing protocol and analyze the performance of the protocol in both the finite-key and infinite-key regime. From numerical simulations, we show that our decoy-state analysis is tighter than Yao Fu et al. That is, we can achieve the nonzero asymptotic secret key rate in long distance with approximate to 200km and we also demonstrate that with a finite size of data (say 10¹¹ to 10¹³ signals) it is possible to perform secure MDI-QCC over reasonable distances.

Cause-effect relationships in analytical surveys: An illustration of statistical issues

Treesearch

Gary L. Gadbury; Hans T. Schreuder

2003-01-01

Establishing cause-effect is critical in the field of natural resources where one may want to know the impact of management practices, wildfires, drought, etc. on water quality and quantity, wildlife, growth and survival of desirable trees for timber production, etc. Yet, key obstacles exist when trying to establish cause-effect in such contexts. Issues involved with...

Tracking Perceived and Observed Growth of Inquiry Practice: A Formative Plan to Improve Professional Development Experiences

ERIC Educational Resources Information Center

Marshall, Jeff C.; Smart, Julie; Horton, Robert M.

2011-01-01

The authors worked with 22 middle school math and science teachers for one year with the goal of improving the quantity and quality of inquiry-based instruction implemented in the classroom. The professional development experience was framed by the 4E x 2 Instruction Model, which combines key components of inquiry instruction (Engage, Explore,…

A Draft Conceptual Framework of Relevant Theories to Inform Future Rigorous Research on Student Service-Learning Outcomes

ERIC Educational Resources Information Center

Whitley, Meredith A.

2014-01-01

While the quality and quantity of research on service-learning has increased considerably over the past 20 years, researchers as well as governmental and funding agencies have called for more rigor in service-learning research. One key variable in improving rigor is using relevant existing theories to improve the research. The purpose of this…

Progression towards Functions: Students' Performance on Three Tasks about Variables from Grades 7 to 12

ERIC Educational Resources Information Center

Ayalon, Michal; Watson, Anne; Lerman, Steve

2016-01-01

Identifying and expressing relations between quantities is a key aspect of understanding and using functions. We are aiming to understand the development of functions understanding throughout school years in Israel. A survey instrument was developed with teachers and given to 20 high and average achieving students from each of years 7-11 and to 10…

Light quantity and photosystem function mediate host susceptibility to turnip mosaic virus via a salicylic acid-independent mechanism

USDA-ARS?s Scientific Manuscript database

Evidence going as far back as the early part of the 20th century suggests that both light and chloroplast function may play key roles in host susceptibility to viruses. Despite the long history of such work, confirmation of these phenomena and a determination of the underlying mechanisms remain elu...

The effect of sampling rate on observed statistics in a correlated random walk

PubMed Central

Rosser, G.; Fletcher, A. G.; Maini, P. K.; Baker, R. E.

2013-01-01

Tracking the movement of individual cells or animals can provide important information about their motile behaviour, with key examples including migrating birds, foraging mammals and bacterial chemotaxis. In many experimental protocols, observations are recorded with a fixed sampling interval and the continuous underlying motion is approximated as a series of discrete steps. The size of the sampling interval significantly affects the tracking measurements, the statistics computed from observed trajectories, and the inferences drawn. Despite the widespread use of tracking data to investigate motile behaviour, many open questions remain about these effects. We use a correlated random walk model to study the variation with sampling interval of two key quantities of interest: apparent speed and angle change. Two variants of the model are considered, in which reorientations occur instantaneously and with a stationary pause, respectively. We employ stochastic simulations to study the effect of sampling on the distributions of apparent speeds and angle changes, and present novel mathematical analysis in the case of rapid sampling. Our investigation elucidates the complex nature of sampling effects for sampling intervals ranging over many orders of magnitude. Results show that inclusion of a stationary phase significantly alters the observed distributions of both quantities. PMID:23740484

Technical and Scientific Aspects of the JET Trace-Tritium Experimental Campaign

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jones, T.T.C.; Brennan, D; Pearce, R.J.H.

The JET Trace Tritium (TTE) programme marked the first use of tritium in experiments under the managerial control of UKAEA, which operates the JET Facility on behalf of EFDA. The introduction of tritium into the plasma by gas fuelling and neutral beam injection, even in trace quantities, required the mobilisation of gram-quantities of tritium gas from the Active Gas Handling System (AGHS) product storage units into the supply lines connected to the torus gas valve and the neutral beam injectors. All systems for DT gas handling, recovery and reprocessing were therefore recommissioned and operating procedures re-established, involving extensive operations staffmore » training. The validation of Key Safety Related Equipment (KSRE) is described with reference to specific examples. The differences between requirements for TTE and full DT operations are shown to be relatively small. The scientific motivation for TTE, such as the possibility to obtain high-quality measurements in key areas such as fuel-ion transport and fast ion dynamics, is described, and the re-establishment and development of JET's 14MeV neutron diagnostic capability for TTE and future DT campaigns are outlined. Some scientific highlights from the TTE campaign are presented.« less

Nitrogen-vacancy centers in diamond: nanoscale sensors for physics and biology.

PubMed

Schirhagl, Romana; Chang, Kevin; Loretz, Michael; Degen, Christian L

2014-01-01

Crystal defects in diamond have emerged as unique objects for a variety of applications, both because they are very stable and because they have interesting optical properties. Embedded in nanocrystals, they can serve, for example, as robust single-photon sources or as fluorescent biomarkers of unlimited photostability and low cytotoxicity. The most fascinating aspect, however, is the ability of some crystal defects, most prominently the nitrogen-vacancy (NV) center, to locally detect and measure a number of physical quantities, such as magnetic and electric fields. This metrology capacity is based on the quantum mechanical interactions of the defect's spin state. In this review, we introduce the new and rapidly evolving field of nanoscale sensing based on single NV centers in diamond. We give a concise overview of the basic properties of diamond, from synthesis to electronic and magnetic properties of embedded NV centers. We describe in detail how single NV centers can be harnessed for nanoscale sensing, including the physical quantities that may be detected, expected sensitivities, and the most common measurement protocols. We conclude by highlighting a number of the diverse and exciting applications that may be enabled by these novel sensors, ranging from measurements of ion concentrations and membrane potentials to nanoscale thermometry and single-spin nuclear magnetic resonance.

Linearized Flux Evolution (LiFE): A technique for rapidly adapting fluxes from full-physics radiative transfer models

NASA Astrophysics Data System (ADS)

Robinson, Tyler D.; Crisp, David

2018-05-01

Solar and thermal radiation are critical aspects of planetary climate, with gradients in radiative energy fluxes driving heating and cooling. Climate models require that radiative transfer tools be versatile, computationally efficient, and accurate. Here, we describe a technique that uses an accurate full-physics radiative transfer model to generate a set of atmospheric radiative quantities which can be used to linearly adapt radiative flux profiles to changes in the atmospheric and surface state-the Linearized Flux Evolution (LiFE) approach. These radiative quantities describe how each model layer in a plane-parallel atmosphere reflects and transmits light, as well as how the layer generates diffuse radiation by thermal emission and by scattering light from the direct solar beam. By computing derivatives of these layer radiative properties with respect to dynamic elements of the atmospheric state, we can then efficiently adapt the flux profiles computed by the full-physics model to new atmospheric states. We validate the LiFE approach, and then apply this approach to Mars, Earth, and Venus, demonstrating the information contained in the layer radiative properties and their derivatives, as well as how the LiFE approach can be used to determine the thermal structure of radiative and radiative-convective equilibrium states in one-dimensional atmospheric models.

Physics with Trapped Antihydrogen

NASA Astrophysics Data System (ADS)

Charlton, Michael

2017-04-01

For more than a decade antihydrogen atoms have been formed by mixing antiprotons and positrons held in arrangements of charged particle (Penning) traps. More recently, magnetic minimum neutral atom traps have been superimposed upon the anti-atom production region, promoting the trapping of a small quantity of the antihydrogen yield. We will review these advances, and describe some of the first physics experiments performed on anrtihydrogen including the observation of the two-photon 1S-2S transition, invesigation of the charge neutrailty of the anti-atom and studies of the ground state hyperfine splitting. We will discuss the physics motivations for undertaking these experiments and describe some near-future initiatives.

Analytic expressions for the black-sky and white-sky albedos of the cosine lobe model.

PubMed

Goodin, Christopher

2013-05-01

The cosine lobe model is a bidirectional reflectance distribution function (BRDF) that is commonly used in computer graphics to model specular reflections. The model is both simple and physically plausible, but physical quantities such as albedo have not been related to the parameterization of the model. In this paper, analytic expressions for calculating the black-sky and white-sky albedos from the cosine lobe BRDF model with integer exponents will be derived, to the author's knowledge for the first time. These expressions for albedo can be used to place constraints on physics-based simulations of radiative transfer such as high-fidelity ray-tracing simulations.

Environmental Influences on Physical Activity among Rural Adults in Montana, United States: Views from Built Environment Audits, Resident Focus Groups, and Key Informant Interviews.

PubMed

Lo, Brian K; Morgan, Emily H; Folta, Sara C; Graham, Meredith L; Paul, Lynn C; Nelson, Miriam E; Jew, Nicolette V; Moffat, Laurel F; Seguin, Rebecca A

2017-10-04

Rural populations in the United States have lower physical activity levels and are at a higher risk of being overweight and suffering from obesity than their urban counterparts. This paper aimed to understand the environmental factors that influence physical activity among rural adults in Montana. Eight built environment audits, 15 resident focus groups, and 24 key informant interviews were conducted between August and December 2014. Themes were triangulated and summarized into five categories of environmental factors: built, social, organizational, policy, and natural environments. Although the existence of active living features was documented by environmental audits, residents and key informants agreed that additional indoor recreation facilities and more well-maintained and conveniently located options were needed. Residents and key informants also agreed on the importance of age-specific, well-promoted, and structured physical activity programs, offered in socially supportive environments, as facilitators to physical activity. Key informants, however, noted that funding constraints and limited political will were barriers to developing these opportunities. Since building new recreational facilities and structures to support active transportation pose resource challenges, especially for rural communities, our results suggest that enhancing existing features, making small improvements, and involving stakeholders in the city planning process would be more fruitful to build momentum towards larger changes.

Progress and Prospect of Physics Research and Education in Taiwan

NASA Astrophysics Data System (ADS)

Raynien Kwo, J.

2010-03-01

Started about two decades ago, the global trend of shifting industrial manufacture power from western developed countries toward developing countries in Asia has in turn become the impetus in building up physical science and research in these areas. A very good example is the remarkable progress of physical research and education in Taiwan, in terms of quantity and quality. The continuous elevation of Taiwan's high education into graduate level plus the government's strong commitment to research and development on a level of 2.62 % GDP have led to an impressive physics program with an annual budget ˜32 million USD from National Science Council in supporting 568 PIs. The investigation scope encompasses high energy and astrophysics, nano and condensed matter, and semiconductor, optoelectronic physics, etc. The former is vigorously conducted via international collaborative efforts of LHC, KEK, ALMA, Pan-STARRS, etc. The latter is driven by vital Taiwan high tech industry mostly semiconductor IC and optoelectronics flourished during this period. The early trend of outflows of BS physics majors to western world for advanced studies has reversed dramatically. Nearly 80% of the BS students continue their MS and PhD degrees in Taiwan, attracted by lucrative job markets of high tech industry. In addition, healthy inflow of high-quality science manpower of well trained PhDs and senior scholars returning to homeland has strengthened the competitiveness. Overall, the physics community in Taiwan is thriving. The annual Physical Society meeting is expanding at a rate of 6%, reaching ˜1800 attendants and 1200 papers, and dedicated to promotions of female physicists and students. The publication quantity of Taiwan in top journals of PRs and PRL is ranked among top 20^th for all fields of physics, and ranked the 6^th in APL. Clearly Taiwan has now emerged as a strong power in applied science, not limited by its population size. Concerted efforts on scientific exchanges are being taken to connect to international societies. The bright outlook of physical science and its vital power in Taiwan is anticipated to provide a stimulus to benefit South East Asia, and have far-reaching impacts on China and worldwide.

Serum Nutritional Biomarkers and Their Associations with Sleep among US Adults in Recent National Surveys

PubMed Central

Beydoun, May A.; Gamaldo, Alyssa A.; Canas, Jose A.; Beydoun, Hind A.; Shah, Mauli T.; McNeely, Jessica M.; Zonderman, Alan B.

2014-01-01

Background The associations between nutritional biomarkers and measures of sleep quantity and quality remain unclear. Methods Cross-sectional data from the National Health and Nutrition Examination Surveys (NHANES) 2005–2006 were used. We selected 2,459 adults aged 20–85, with complete data on key variables. Five sleep measures were constructed as primary outcomes: (A) Sleep duration; (B) Sleep disorder; (C) Three factors obtained from factor analysis of 15 items and labeled as “Poor sleep-related daytime dysfunction” (Factor 1), “Sleepiness” (Factor 2) and “Sleep disturbance” (Factor 3). Main exposures were serum concentrations of key nutrients, namely retinol, retinyl esters, carotenoids (α-carotene, β-carotene, β-cryptoxanthin, lutein+zeaxanthin, lycopene), folate, vitamin B-12, total homocysteine (tHcy), vitamin C, 25-hydroxyvitamin D (25(OH)D) and vitamin E. Main analyses consisted of multiple linear, logistic and multinomial logit models. Results Among key findings, independent inverse associations were found between serum vitamin B-12 and sleep duration, 25(OH)D and sleepiness (as well as insomnia), and between folate and sleep disturbance. Serum total carotenoids concentration was linked to higher odds of short sleep duration (i.e. 5–6 h per night) compared to normal sleep duration (7–8 h per night). Conclusions A few of the selected serum nutritional biomarkers were associated with sleep quantity and quality. Longitudinal studies are needed to ascertain temporality and assess putative causal relationships. PMID:25137304

Correlation of soil microbes and soil micro-environment under long-term safflower (Carthamus tinctorius L.) plantation in China.

PubMed

Lu, Shuang; Quan, Wang; Wang, Shao-Ming; Liu, Hong-Ling; Tan, Yong; Zeng, Guang-Ping; Zhang, Xia

2013-04-01

Microbial community structure and ecological functions are influenced by interactions between above and belowground biota. There is an urgent need for intensive monitoring of microbes feedback of soil micro-ecosystem for setting up a good agricultural practice. Recent researches have revealed that many soils characteristic can effect microbial community structure. In the present study factors affecting microbial community structure and soil in Carthamus tinctorius plantations in arid agricultural ecosystem of northern Xinjiang, China were identified. The result of the study revealed that soil type was the key factor in safflower yield; Unscientific field management resulted high fertility level (bacteria dominant) of soil to turn to low fertility level (fungi dominant), and Detruded Canonical Correspondence Analysis (DCCA) showed that soil water content, organic matter, available N, P and K were the dominant factors affecting distribution of microbial community. Soil water content showed a significant positive correlation with soil microbes quantity (P < 0.01), while others showed a significant quantity correlation with soil microbe quantity (P < 0.05).

Microstructurally-sensitive fatigue crack nucleation in Ni-based single and oligo crystals

NASA Astrophysics Data System (ADS)

Chen, Bo; Jiang, Jun; Dunne, Fionn P. E.

2017-09-01

An integrated experimental, characterisation and computational crystal plasticity study of cyclic plastic beam loading has been carried out for nickel single crystal (CMSX4) and oligocrystal (MAR002) alloys in order to assess quantitatively the mechanistic drivers for fatigue crack nucleation. The experimentally validated modelling provides knowledge of key microstructural quantities (accumulated slip, stress and GND density) at experimentally observed fatigue crack nucleation sites and it is shown that while each of these quantities is potentially important in crack nucleation, none of them in its own right is sufficient to be predictive. However, the local (elastic) stored energy density, measured over a length scale determined by the density of SSDs and GNDs, has been shown to predict crack nucleation sites in the single and oligocrystals tests. In addition, once primary nucleated cracks develop and are represented in the crystal model using XFEM, the stored energy correctly identifies where secondary fatigue cracks are observed to nucleate in experiments. This (Griffith-Stroh type) quantity also correctly differentiates and explains intergranular and transgranular fatigue crack nucleation.

Optical characterization of natural protective varnishes and their influences on perception of painted samples

NASA Astrophysics Data System (ADS)

Radis, M.; Iacomussi, P.; Aghemo, C.; Rossi, G.

2017-07-01

Interdependence between color and gloss is a concept well-known by artists, especially by old masters, but is not usually considered in material characterization. Indeed, measurement methods and definitions consider these two attributes individually. This research investigates how the available measurement methods for gloss and color (saturation) fit with corresponding perceptual qualities, glossiness and saturation. The definitions of both measured quantities, as well the measurement methodologies, were developed for reference materials (ceramic tiles for color and dark glass specimen for gloss) not representative of artwork materials and do not consider observation conditions similar with those adopted during exhibitions. The prediction of material appearance is recognized as one of the most important challenges in applied metrology, because appearance is the key to achieve effective exhibitions and consumers choices. The results of this study highlight that the two perceived qualities are mutually related, as well the measured quantities: gloss and saturation mutually interfere and the measurement methods and quantities are not uniform with the perceived qualities and the colorimetric coordinate C* no longer describes the perceived saturation.

Exact near-onset analysis of the spin-density-wave instability in ferromagnetic superconductors: The linearly polarized state

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hu, C.

1984-09-01

Using an approach similar to Abvikosov's theory of the vortex state near H/sub c/2, we have performed an exact, near-onset analysis of a spin-density-wave instability leading to the ''linearly polarized state'' of Greenside et al. in ferromagnetic superconductors. The approach is based on a generalized Ginzburg-Landau theory for such materials, as formulated by Blount and Varma. Two models have been considered. In the (..cap alpha..,..beta..) model, where the bulk magnetic energy is taken to be (1/2)..cap alpha../sub m/M/sup 2/+(1/4)..beta../sub m/M/sup 4/, we find the transition to be second order, and obtain explicit formulas for various physical quantities to leading ordermore » in the deviation from onset. We have also rigorously analyzed the most favored spatial structure just below onset, among all possibilities allowed by the instability, and have concluded that a plane-wave-like structure is favored in a physical limit considered. In the (..cap alpha..,..gamma..) model, where the bulk magnetic energy is taken to be (1/2)..cap alpha../sub m/M/sup 2/+(1/6)..gamma../sub m/M/sup 6/ as is supported by recent experiments for ErRh/sub 4/B/sub 4/, we find the transition to be first order. This approach is then confined to an unphysical branch, which does not permit us to calculate various physical quantities on the physical branch.« less

SU-F-T-193: Evaluation of a GPU-Based Fast Monte Carlo Code for Proton Therapy Biological Optimization

DOE Office of Scientific and Technical Information (OSTI.GOV)

Taleei, R; Qin, N; Jiang, S

2016-06-15

Purpose: Biological treatment plan optimization is of great interest for proton therapy. It requires extensive Monte Carlo (MC) simulations to compute physical dose and biological quantities. Recently, a gPMC package was developed for rapid MC dose calculations on a GPU platform. This work investigated its suitability for proton therapy biological optimization in terms of accuracy and efficiency. Methods: We performed simulations of a proton pencil beam with energies of 75, 150 and 225 MeV in a homogeneous water phantom using gPMC and FLUKA. Physical dose and energy spectra for each ion type on the central beam axis were scored. Relativemore » Biological Effectiveness (RBE) was calculated using repair-misrepair-fixation model. Microdosimetry calculations were performed using Monte Carlo Damage Simulation (MCDS). Results: Ranges computed by the two codes agreed within 1 mm. Physical dose difference was less than 2.5 % at the Bragg peak. RBE-weighted dose agreed within 5 % at the Bragg peak. Differences in microdosimetric quantities such as dose average lineal energy transfer and specific energy were < 10%. The simulation time per source particle with FLUKA was 0.0018 sec, while gPMC was ∼ 600 times faster. Conclusion: Physical dose computed by FLUKA and gPMC were in a good agreement. The RBE differences along the central axis were small, and RBE-weighted dose difference was found to be acceptable. The combined accuracy and efficiency makes gPMC suitable for proton therapy biological optimization.« less

Takahasi Nearest-Neighbour Gas Revisited II: Morse Gases

NASA Astrophysics Data System (ADS)

Matsumoto, Akira

2011-12-01

Some thermodynamic quantities for the Morse potential are analytically evaluated at an isobaric process. The parameters of Morse gases for 21 substances are obtained by the second virial coefficient data and the spectroscopic data of diatomic molecules. Also some thermodynamic quantities for water are calculated numerically and drawn graphically. The inflexion point of the length L which depends on temperature T and pressure P corresponds physically to a boiling point. L indicates the liquid phase from lower temperature to the inflexion point and the gaseous phase from the inflexion point to higher temperature. The boiling temperatures indicate reasonable values compared with experimental data. The behaviour of L suggests a chance of a first-order phase transition in one dimension.

FAST TRACK COMMUNICATION: Exact and simple results for the XYZ and strongly interacting fermion chains

NASA Astrophysics Data System (ADS)

Fendley, Paul; Hagendorf, Christian

2010-10-01

We conjecture exact and simple formulas for some physical quantities in two quantum chains. A classic result of this type is Onsager, Kaufman and Yang's formula for the spontaneous magnetization in the Ising model, subsequently generalized to the chiral Potts models. We conjecture that analogous results occur in the XYZ chain when the couplings obey JxJy + JyJz + JxJz = 0, and in a related fermion chain with strong interactions and supersymmetry. We find exact formulas for the magnetization and gap in the former, and the staggered density in the latter, by exploiting the fact that certain quantities are independent of finite-size effects.

Lattice QCD and heavy ion collisions: a review of recent progress.

PubMed

Ratti, Claudia

2018-04-04

In the last few years, numerical simulations of QCD on the lattice have reached a new level of accuracy. A wide range of thermodynamic quantities is now available in the continuum limit and for physical quark masses. This allows a comparison with measurements from heavy ion collisions for the first time. Furthermore, calculations of dynamical quantities are also becoming available. The combined effort from first principles and experiment allows us to gain an unprecedented understanding of the properties of quark-gluon plasma. I will review the state-of-the-art results from lattice simulations and connect them to the experimental information from RHIC and the LHC. © 2018 IOP Publishing Ltd.

Design of the Coordinate Transformation Function for Cylindrical Acoustic Cloaks with a Quantity of Discrete Layers

NASA Astrophysics Data System (ADS)

Cai, Li; Wen, Ji-Hong; Yu, Dian-Long; Lu, Zhi-Miao; Wen, Xi-Sen

2014-09-01

Acoustic cloak based on coordinate transformation is of great topical interest and has promise in potential applications such as sound transparency and insulation. The frequency response of acoustic cloaks with a quantity of discrete homogeneous layers is analyzed by the acoustic scattering theory. The effect of coordinate transformation function on the acoustic total scattering cross section is discussed to achieve low scattering with only a few layers of anisotropic metamaterials. Also, the physics of acoustic wave interaction with the interfaces between the discrete layers inside the cloak shell is discussed. These results provide a better way of designing a multilayered acoustic cloak with fewer layers.

Nuclear ``pasta'' structures in low-density nuclear matter and properties of the neutron-star crust

NASA Astrophysics Data System (ADS)

Okamoto, Minoru; Maruyama, Toshiki; Yabana, Kazuhiro; Tatsumi, Toshitaka

2013-08-01

In the neutron-star crust, nonuniform structure of nuclear matter—called the “pasta” structure—is expected. From recent studies of giant flares in magnetars, these structures might be related to some observables and physical quantities of the neutron-star crust. To investigate the above quantities, we numerically explore the pasta structure with a fully three-dimensional geometry and study the properties of low-density nuclear matter, based on the relativistic mean-field model and the Thomas-Fermi approximation. We observe typical pasta structures for fixed proton number fraction and two of them for cold catalyzed matter. We also discuss the crystalline configuration of “pasta.”

Measuring effective temperatures in a generalized Gibbs ensemble

DOE PAGES

Foini, Laura; Gambassi, Andrea; Konik, Robert; ...

2017-05-11

The local physical properties of an isolated quantum statistical system in the stationary state reached long after a quench are generically described by the Gibbs ensemble, which involves only its Hamiltonian and the temperature as a parameter. Additional quantities conserved by the dynamics intervene in the description of the stationary state, if the system is instead integrable. The resulting generalized Gibbs ensemble involves a number of temperature-like parameters, the determination of which is practically difficult. We argue that in a number of simple models these parameters can be effectively determined by using fluctuation-dissipation relationships between response and correlation functions ofmore » natural observables, quantities which are accessible in experiments.« less

Wireless Infrared Data Link

NASA Technical Reports Server (NTRS)

Roth, Timothy E.

1995-01-01

Infrared transmitter and receiver designed for wireless transmission of information on measured physical quantity (for example, temperature) from transducer device to remote-acquisition system. In transmitter, output of transducer amplified and shifted with respect to bias or reference level, then fed to voltage-to-frequency converter to control frequency of repetition of current pulses applied to infrared-light-emitting diode. In receiver, frequency of repetition of pulses converted back into voltage indicative of temperature or other measured quantity. Potential applications include logging data while drilling for oil, transmitting measurements from rotors in machines without using slip rings, remote monitoring of temperatures and pressures in hazardous locations, and remote continuous monitoring of temperatures and blood pressures in medical patients, who thus remain mobile.

Wave propagation in a random medium

NASA Technical Reports Server (NTRS)

Lee, R. W.; Harp, J. C.

1969-01-01

A simple technique is used to derive statistical characterizations of the perturbations imposed upon a wave (plane, spherical or beamed) propagating through a random medium. The method is essentially physical rather than mathematical, and is probably equivalent to the Rytov method. The limitations of the method are discussed in some detail; in general they are restrictive only for optical paths longer than a few hundred meters, and for paths at the lower microwave frequencies. Situations treated include arbitrary path geometries, finite transmitting and receiving apertures, and anisotropic media. Results include, in addition to the usual statistical quantities, time-lagged functions, mixed functions involving amplitude and phase fluctuations, angle-of-arrival covariances, frequency covariances, and other higher-order quantities.

Quality versus quantity: Foraging decisions in the honeybee (Apis mellifera scutellata) feeding on wildflower nectar and fruit juice.

PubMed

Shackleton, Kyle; Balfour, Nicholas J; Al Toufailia, Hasan; Gaioski, Roberto; de Matos Barbosa, Marcela; Silva, Carina A de S; Bento, José M S; Alves, Denise A; Ratnieks, Francis L W

2016-10-01

Foraging animals must often decide among resources which vary in quality and quantity. Nectar is a resource that exists along a continuum of quality in terms of sugar concentration and is the primary energy source for bees. Alternative sugar sources exist, including fruit juice, which generally has lower energetic value than nectar. We observed many honeybees ( Apis mellifera scutellata ) foraging on juice from fallen guava ( Psidium guajava ) fruit near others foraging on nectar. To investigate whether fruit and nectar offered contrasting benefits of quality and quantity, we compared honeybee foraging performance on P. guajava fruit versus two wildflowers growing within 50 m, Richardia brasiliensis and Tridax procumbens . Bees gained weight significantly faster on fruit, 2.72 mg/min, than on either flower (0.17 and 0.12 mg/min, respectively). However, the crop sugar concentration of fruit foragers was significantly lower than for either flower (12.4% vs. 37.0% and 22.7%, respectively). Fruit foragers also spent the most time handling and the least time flying, suggesting that fruit juice was energetically inexpensive to collect. We interpret honeybee foraging decisions in the context of existing foraging models and consider how nest-patch distance may be a key factor for central place foragers choosing between resources of contrasting quality and quantity. We also discuss how dilute solutions, such as fruit juice, can help maintain colony sugar-water balance. These results show the benefits of feeding on resources with contrasting quality and quantity and that even low-quality resources have value.

Childhood Adversities and Adult Cardiometabolic Health: Does the Quantity, Timing, and Type of Adversity Matter?

PubMed Central

Friedman, Esther M.; Montez, Jennifer Karas; Sheehan, Connor McDevitt; Guenewald, Tara L.; Seeman, Teresa E.

2015-01-01

Objective Adverse events in childhood can indelibly influence adult health. While evidence for this association has mounted, a fundamental set of questions about how to operationalize adverse events has been understudied. Method We used data from the National Survey of Midlife Development in the United States to examine how quantity, timing, and types of adverse events in childhood are associated with adult cardiometabolic health. Results The best-fitting specification of quantity of events was a linear measure reflecting a dose–response relationship. Timing of event mattered less than repeated exposure to events. Regarding the type of event, academic interruptions and sexual/physical abuse were most important. Adverse childhood events elevated the risk of diabetes and obesity similarly for men and women but had a greater impact on women’s risk of heart disease. Discussion Findings demonstrate the insights that can be gleaned about the early-life origins of adult health by examining operationalization of childhood exposures. PMID:25903978

Uncertainty in estimates of the number of extraterrestrial civilizations

NASA Technical Reports Server (NTRS)

Sturrock, P. A.

1980-01-01

An estimation of the number N of communicative civilizations is made by means of Drake's formula which involves the combination of several quantities, each of which is to some extent uncertain. It is shown that the uncertainty in any quantity may be represented by a probability distribution function, even if that quantity is itself a probability. The uncertainty of current estimates of N is derived principally from uncertainty in estimates of the lifetime of advanced civilizations. It is argued that this is due primarily to uncertainty concerning the existence of a Galactic Federation which is in turn contingent upon uncertainty about whether the limitations of present-day physics are absolute or (in the event that there exists a yet undiscovered hyperphysics) transient. It is further argued that it is advantageous to consider explicitly these underlying assumptions in order to compare the probable numbers of civilizations operating radio beacons, permitting radio leakage, dispatching probes for radio surveillance for dispatching vehicles for manned surveillance.

Peeling off effects in vertically aligned Fe3C filled carbon nanotubes films grown by pyrolysis of ferrocene

NASA Astrophysics Data System (ADS)

Boi, Filippo S.; Medranda, Daniel; Ivaturi, Sameera; Wang, Jiayu; Guo, Jian; Lan, Mu; Wen, Jiqiu; Wang, Shanling; He, Yi; Mountjoy, Gavin; Willis, Maureen A. C.; Xiang, Gang

2017-06-01

We report the observation of an unusual self-peeling effect which allows the synthesis of free standing vertically aligned carbon nanotube films filled with large quantities of Fe3C and small quantities of γ-Fe crystals. We demonstrate that this effect depends on the interplay of three main factors: (1) the physical interactions between the chosen substrate surface and grown carbon nanotubes (CNTs), which is fixed by the composition of the used substrate (111 SiO2/Si or quartz), (2) the CNT-CNT Van der Waals interactions, and (3) the differential thermal contraction between the grown CNT film and the used substrate, which is fixed by the cooling rate differences between the grown film and the used quartz or Si/SiO2 substrates. The width and stability of these films are then further increased to cm-scale by addition of small quantities of toluene to the ferrocene precursor.

Quantum reference frames and their applications to thermodynamics.

PubMed

Popescu, Sandu; Sainz, Ana Belén; Short, Anthony J; Winter, Andreas

2018-07-13

We construct a quantum reference frame, which can be used to approximately implement arbitrary unitary transformations on a system in the presence of any number of extensive conserved quantities, by absorbing any back action provided by the conservation laws. Thus, the reference frame at the same time acts as a battery for the conserved quantities. Our construction features a physically intuitive, clear and implementation-friendly realization. Indeed, the reference system is composed of the same types of subsystems as the original system and is finite for any desired accuracy. In addition, the interaction with the reference frame can be broken down into two-body terms coupling the system to one of the reference frame subsystems at a time. We apply this construction to quantum thermodynamic set-ups with multiple, possibly non-commuting conserved quantities, which allows for the definition of explicit batteries in such cases.This article is part of a discussion meeting issue 'Foundations of quantum mechanics and their impact on contemporary society'. © 2018 The Author(s).

The sharing of water between society and ecosystems: from conflict to catchment-based co-management.

PubMed Central

Wallace, J S; Acreman, M C; Sullivan, C A

2003-01-01

Human uses of freshwater resources are increasing rapidly as the world population rises. As this happens, less water is left to support aquatic and associated ecosystems. To minimize future human water shortages and undesirable environmental impacts, more equitable sharing of water resources between society and nature is required. This will require physical quantities and social values to be placed on both human and aquatic ecosystem requirements. Current water valuation systems are dominated by economic values and this paper illustrates new quantification and valuation methods that take more account of human well-being and environmental impacts. The key to the effective implementation of these more equitable water allocation methods is the use of catchment-based integrated water resources management. This holistic framework makes it possible for human and ecosystem water requirements and the interactions between them to be better understood. This knowledge provides the foundation for incorporating relevant social factors so that water policies and laws can be developed to make best use of limited water resources. Catchment-based co-management can therefore help to ensure more effective sharing of water between people and nature. PMID:14728795

Effect of Discontinuities and Uncertainties on the Response and Failure of Composite Structures

NASA Technical Reports Server (NTRS)

Noor, Ahmed K.; Perry, Ferman W.; Poteat, Marcia M. (Technical Monitor)

2000-01-01

The overall goal of this research was to assess the effect of discontinuities and uncertainties on the nonlinear response and failure of composite structures subjected to combined mechanical and thermal loads. The four key elements of the study were: (1) development of simple and efficient procedures for the accurate determination of transverse shear and transverse normal stresses in structural sandwiches as well as in unstiffened and stiffened composite panels and shells; (2) study the effects of transverse stresses on the response, damage initiation and propagation in composite and sandwich structures; (3) use of hierarchical sensitivity coefficients to identify the major parameters that affect the response and damage in each of the different levels in the hierarchy (micro-mechanical, layer, panel, subcomponent and component levels); and (4) application of fuzzy set techniques to identify the range and variation of possible responses. The computational models developed were used in conjunction with experiments, to understand the physical phenomena associated with the nonlinear response and failure of composite and sandwich structures. A toolkit was developed for use in conjunction with deterministic analysis programs to help the designer in assessing the effect of uncertainties in the different computational model parameters on the variability of the response quantities.

An Acrylonitrile–Butadiene–Lignin Renewable Skin with Programmable and Switchable Electrical Conductivity for Stress/Strain-Sensing Applications

DOE PAGES

Nguyen, Ngoc A.; Meek, Kelly M.; Bowland, Christopher C.; ...

2017-12-28

We report an approach for programming electrical conductivity of a bio-based leathery skin devised with a layer of 60 nm metallic nanoparticles. Lignin-based renewable shape-memory materials were made, for the first time, to program and restore the materials’ electrical conductivity after repeated deformation up to 100% strain amplitude, at a temperature 60–115 °C above the glass transition temperature (T g) of the rubbery matrix. We cross-linked lignin macromolecules with an acrylonitrile–butadiene rubbery melt in high quantities ranging from 40 to 60 wt % and processed the resulting thermoplastics into thin films. Chemical and physical networks within the polymeric materials significantlymore » enhanced key characteristics such as mechanical stiffness, strain fixity, and temperature-stimulated recovery of shape. The branched structures of the guaiacylpropane-dominant softwood lignin significantly improve the rubber’s T g and produced a film with stored and recoverable elastic work density that was an order of magnitude greater than those of the neat rubber and of samples made with syringylpropane-rich hardwood lignin. The devices could exhibit switching of conductivity before and after shape recovery.« less

Ten key questions about the management of water in the Yellow River basin.

PubMed

Barnett, Jon; Webber, Michael; Wang, Mark; Finlayson, Brian; Dickinson, Debbie

2006-08-01

Water is scarce in many regions of the world, clean water is difficult to find in most developing countries, there are conflicts between irrigation needs and urban demands, and there is wide debate over appropriate means of resolving these problems. Similarly, in China, there is limited understanding of the ways in which people, groups, and institutions contribute to, are affected by, and respond to changes in water quantity and quality. We use the example of the Yellow River basin to argue that these social, managerial, and policy dimensions of the present water problems are significant and overshadow the physical ones. Despite this, they receive relatively little attention in the research agenda, particularly of the lead agencies in the management of the Yellow River basin. To this end, we ask ten research questions needed to address the policy needs of water management in the basin, split into two groups of five. The first five relate to the importance of water in this basin and the changes that have affected water problems and will continue to do so. The second five questions represent an attempt to explore possible solutions to these problems.

Ammonium-tungstate-promoted growth of boron nitride nanotubes

NASA Astrophysics Data System (ADS)

E, Songfeng; Li, Chaowei; Li, Taotao; Geng, Renjie; Li, Qiulong; Lu, Weibang; Yao, Yagang

2018-05-01

Ammonium tungstate ((NH4)10W12O41 · xH2O) is a kind of oxygen-containing ammonium salt. The following study proves that it can be successfully used as a metal oxide alternative to produce boron oxide (B2O2) by oxidizing boron (B) in a traditional boron oxide chemical vapor deposition (BOCVD) process. This special oxidant promotes the simplistic fabrication of boron nitride nanotubes (BNNTs) in a conventional horizontal tube furnace, an outcome which may have resulted from its strong oxidizability. The experimental results demonstrate that the mole ratio of B and (NH4)10W12O41 · xH2O is a key parameter in determining the formation, quality and quantity of BNNTs when stainless steel is employed as a catalyst. We also found that Mg(NO3)2 and MgO nanoparticles (NPs) can be used as catalysts to grow BNNTs with the same precursor. The BNNTs obtained from the Mg(NO3)2 catalyst were straighter than those obtained from the MgO NP catalyst. This could have been due to the different physical forms of the catalysts that were used.

Ammonium-tungstate-promoted growth of boron nitride nanotubes.

PubMed

E, Songfeng; Li, Chaowei; Li, Taotao; Geng, Renjie; Li, Qiulong; Lu, Weibang; Yao, Yagang

2018-05-11

Ammonium tungstate ((NH 4 ) 10 W 12 O 41  · xH 2 O) is a kind of oxygen-containing ammonium salt. The following study proves that it can be successfully used as a metal oxide alternative to produce boron oxide (B 2 O 2 ) by oxidizing boron (B) in a traditional boron oxide chemical vapor deposition (BOCVD) process. This special oxidant promotes the simplistic fabrication of boron nitride nanotubes (BNNTs) in a conventional horizontal tube furnace, an outcome which may have resulted from its strong oxidizability. The experimental results demonstrate that the mole ratio of B and (NH 4 ) 10 W 12 O 41  · xH 2 O is a key parameter in determining the formation, quality and quantity of BNNTs when stainless steel is employed as a catalyst. We also found that Mg(NO 3 ) 2 and MgO nanoparticles (NPs) can be used as catalysts to grow BNNTs with the same precursor. The BNNTs obtained from the Mg(NO 3 ) 2 catalyst were straighter than those obtained from the MgO NP catalyst. This could have been due to the different physical forms of the catalysts that were used.

Nanomaterials for Hydrogen Storage Applications: A Review

DOE PAGES

Niemann, Michael U.; Srinivasan, Sesha S.; Phani, Ayala R.; ...

2008-01-01

Nmore » anomaterials have attracted great interest in recent years because of the unusual mechanical, electrical, electronic, optical, magnetic and surface properties. The high surface/volume ratio of these materials has significant implications with respect to energy storage. Both the high surface area and the opportunity for nanomaterial consolidation are key attributes of this new class of materials for hydrogen storage devices. anostructured systems including carbon nanotubes, nano-magnesium based hydrides, complex hydride/carbon nanocomposites, boron nitride nanotubes, TiS 2 / MoS 2 nanotubes, alanates, polymer nanocomposites, and metal organic frameworks are considered to be potential candidates for storing large quantities of hydrogen. Recent investigations have shown that nanoscale materials may offer advantages if certain physical and chemical effects related to the nanoscale can be used efficiently. The present review focuses the application of nanostructured materials for storing atomic or molecular hydrogen. The synergistic effects of nanocrystalinity and nanocatalyst doping on the metal or complex hydrides for improving the thermodynamics and hydrogen reaction kinetics are discussed. In addition, various carbonaceous nanomaterials and novel sorbent systems (e.g. carbon nanotubes, fullerenes, nanofibers, polyaniline nanospheres and metal organic frameworks etc.) and their hydrogen storage characteristics are outlined.« less

Oscillatory slip flow past a spherical inclusion embedded in a Brinkman medium

NASA Astrophysics Data System (ADS)

Palaniappan, D.

2016-11-01

Non-steady flow past an impermeable sphere embedded in a porous medium is investigated based on Brinkman model with Navier slip conditions. Exact analytic solution for the stream-function - involving modified Bessel function of the second kind - describing the slow oscillatory flow around a rigid spherical inclusion is obtained in the limit of low-Reynolds-number. The key parameters such as the frequency of oscillation λ, the permeability constant δ, and the slip coefficient ξ control the flow fields and physical quantities in the entire flow domain. Local streamlines for fixed times demonstrate the variations in flow patterns. Closed form expressions for the tangential velocity profile, wall shear stress, and the force acting on the sphere are computed and compared with the existing results. It is noted that the slip parameter in the range 0 <= ξ <= 0 . 5 has a significant effect in reducing the stress and force. The steady-state velocity overshoot behavior in the vicinity of the sphere is re-iterated. In the limit of large permeability, Darcy (potential) flow is recovered outside a boundary layer. The results are of some interest in predicting maximum wall stress and pressure drop associated with biological models in fibrous media.

Oscillatory flow past a slip cylindrical inclusion embedded in a Brinkman medium

NASA Astrophysics Data System (ADS)

Palaniappan, D.

2015-11-01

Transient flow past a circular cylinder embedded in a porous medium is studied based on Brinkman model with Navier slip conditions. Closed form analytic solution for the stream-function describing slow oscillatory flow around a solid cylindrical inclusion is obtained in the limit of low-Reynolds-number. The key parameters such as the frequency of oscillation λ, the permeability constant δ, and the slip coefficient ξ dictate the flow fields and physical quantities in the entire flow domain. Asymptotic steady-state analysis when δ --> 0 reveals the paradoxical behavior detected by Stokes. Local streamlines for small times demonstrate interesting flow patterns. Rapid transitions including flow separations and eddies are observed far away from the solid inclusion. Analytic expressions for the wall shear stress and the force acting on the cylinder are computed and compared with existing results. It is noted that the slip parameter in the range 0 <= ξ <= 0 . 5 has a significant effect in reducing the stress and force. In the limit of large permeability, Darcy (potential) flow is recovered outside a boundary layer. The results are of some interest in predicting maximum wall stress and pressure drop associated with biological models in fibrous media.

Resource acquisition, distribution and end-use efficiencies and the growth of industrial society

NASA Astrophysics Data System (ADS)

Jarvis, A. J.; Jarvis, S. J.; Hewitt, C. N.

2015-10-01

A key feature of the growth of industrial society is the acquisition of increasing quantities of resources from the environment and their distribution for end-use. With respect to energy, the growth of industrial society appears to have been near-exponential for the last 160 years. We provide evidence that indicates that the global distribution of resources that underpins this growth may be facilitated by the continual development and expansion of near-optimal directed networks (roads, railways, flight paths, pipelines, cables etc.). However, despite this continual striving for optimisation, the distribution efficiencies of these networks must decline over time as they expand due to path lengths becoming longer and more tortuous. Therefore, to maintain long-term exponential growth the physical limits placed on the distribution networks appear to be counteracted by innovations deployed elsewhere in the system, namely at the points of acquisition and end-use of resources. We postulate that the maintenance of the growth of industrial society, as measured by global energy use, at the observed rate of ~ 2.4 % yr-1 stems from an implicit desire to optimise patterns of energy use over human working lifetimes.

Evaluating the effects of modeling errors for isolated finite three-dimensional targets

NASA Astrophysics Data System (ADS)

Henn, Mark-Alexander; Barnes, Bryan M.; Zhou, Hui

2017-10-01

Optical three-dimensional (3-D) nanostructure metrology utilizes a model-based metrology approach to determine critical dimensions (CDs) that are well below the inspection wavelength. Our project at the National Institute of Standards and Technology is evaluating how to attain key CD and shape parameters from engineered in-die capable metrology targets. More specifically, the quantities of interest are determined by varying the input parameters for a physical model until the simulations agree with the actual measurements within acceptable error bounds. As in most applications, establishing a reasonable balance between model accuracy and time efficiency is a complicated task. A well-established simplification is to model the intrinsically finite 3-D nanostructures as either periodic or infinite in one direction, reducing the computationally expensive 3-D simulations to usually less complex two-dimensional (2-D) problems. Systematic errors caused by this simplified model can directly influence the fitting of the model to the measurement data and are expected to become more apparent with decreasing lengths of the structures. We identify these effects using selected simulation results and present experimental setups, e.g., illumination numerical apertures and focal ranges, that can increase the validity of the 2-D approach.

Artificial Mitochondria Transfer: Current Challenges, Advances, and Future Applications

PubMed Central

Aponte, Pedro M.

2017-01-01

The objective of this review is to outline existing artificial mitochondria transfer techniques and to describe the future steps necessary to develop new therapeutic applications in medicine. Inspired by the symbiotic origin of mitochondria and by the cell's capacity to transfer these organelles to damaged neighbors, many researchers have developed procedures to artificially transfer mitochondria from one cell to another. The techniques currently in use today range from simple coincubations of isolated mitochondria and recipient cells to the use of physical approaches to induce integration. These methods mimic natural mitochondria transfer. In order to use mitochondrial transfer in medicine, we must answer key questions about how to replicate aspects of natural transport processes to improve current artificial transfer methods. Another priority is to determine the optimum quantity and cell/tissue source of the mitochondria in order to induce cell reprogramming or tissue repair, in both in vitro and in vivo applications. Additionally, it is important that the field explores how artificial mitochondria transfer techniques can be used to treat different diseases and how to navigate the ethical issues in such procedures. Without a doubt, mitochondria are more than mere cell power plants, as we continue to discover their potential to be used in medicine. PMID:28751917

An Acrylonitrile–Butadiene–Lignin Renewable Skin with Programmable and Switchable Electrical Conductivity for Stress/Strain-Sensing Applications

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nguyen, Ngoc A.; Meek, Kelly M.; Bowland, Christopher C.

We report an approach for programming electrical conductivity of a bio-based leathery skin devised with a layer of 60 nm metallic nanoparticles. Lignin-based renewable shape-memory materials were made, for the first time, to program and restore the materials’ electrical conductivity after repeated deformation up to 100% strain amplitude, at a temperature 60–115 °C above the glass transition temperature (T g) of the rubbery matrix. We cross-linked lignin macromolecules with an acrylonitrile–butadiene rubbery melt in high quantities ranging from 40 to 60 wt % and processed the resulting thermoplastics into thin films. Chemical and physical networks within the polymeric materials significantlymore » enhanced key characteristics such as mechanical stiffness, strain fixity, and temperature-stimulated recovery of shape. The branched structures of the guaiacylpropane-dominant softwood lignin significantly improve the rubber’s T g and produced a film with stored and recoverable elastic work density that was an order of magnitude greater than those of the neat rubber and of samples made with syringylpropane-rich hardwood lignin. The devices could exhibit switching of conductivity before and after shape recovery.« less

Water flows in the Spanish economy: agri-food sectors, trade and households diets in an input-output framework.

PubMed

Cazcarro, Ignacio; Duarte, Rosa; Sánchez-Chóliz, Julio

2012-06-19

Seeking to advance our knowledge of water flows and footprints and the factors underlying them, we apply, on the basis of an extended 2004 Social Accounting Matrix for Spain, an open Leontief model in which households and foreign trade are the exogenous accounts. The model shows the water embodied in products bought by consumers (which we identify with the Water Footprint) and in trade (identified with virtual water trade). Activities with relevant water inflows and outflows such as the agrarian sector, textiles, and the agri-food industry are examined in detail using breakdowns of the relevant accounts. The data reflect only physical consumption, differentiating between green and blue water. The results reveal that Spain is a net importer of water. Flows are then related to key trading partners to show the large quantities involved. The focus on embodied (or virtual) water by activity is helpful to distinguish indirect from direct consumption as embodied water can be more than 300 times direct consumption in some food industry activities. Finally, a sensitivity analysis applied to changes in diets shows the possibility of reducing water uses by modifying households' behavior to encourage healthier eating.

Perceptual geometry of space and form: visual perception of natural scenes and their virtual representation

NASA Astrophysics Data System (ADS)

Assadi, Amir H.

2001-11-01

Perceptual geometry is an emerging field of interdisciplinary research whose objectives focus on study of geometry from the perspective of visual perception, and in turn, apply such geometric findings to the ecological study of vision. Perceptual geometry attempts to answer fundamental questions in perception of form and representation of space through synthesis of cognitive and biological theories of visual perception with geometric theories of the physical world. Perception of form and space are among fundamental problems in vision science. In recent cognitive and computational models of human perception, natural scenes are used systematically as preferred visual stimuli. Among key problems in perception of form and space, we have examined perception of geometry of natural surfaces and curves, e.g. as in the observer's environment. Besides a systematic mathematical foundation for a remarkably general framework, the advantages of the Gestalt theory of natural surfaces include a concrete computational approach to simulate or recreate images whose geometric invariants and quantities might be perceived and estimated by an observer. The latter is at the very foundation of understanding the nature of perception of space and form, and the (computer graphics) problem of rendering scenes to visually invoke virtual presence.

Argo workstation: a key component of operational oceanography

NASA Astrophysics Data System (ADS)

Dong, Mingmei; Xu, Shanshan; Miao, Qingsheng; Yue, Xinyang; Lu, Jiawei; Yang, Yang

2018-02-01

Operational oceanography requires the quantity, quality, and availability of data set and the timeliness and effectiveness of data products. Without steady and strong operational system supporting, operational oceanography will never be proceeded far. In this paper we describe an integrated platform named Argo Workstation. It operates as a data processing and management system, capable of data collection, automatic data quality control, visualized data check, statistical data search and data service. After it is set up, Argo workstation provides global high quality Argo data to users every day timely and effectively. It has not only played a key role in operational oceanography but also set up an example for operational system.

[Protein intake in selected youth groups of different physical activity and requirements for athletes].

PubMed

Nazarewicz, Rafał; Babicz-Zielińska, Ewa

2004-01-01

The aim of the study was to investigate protein intake in groups of different physical activity. The research was undertaken over a group of young people of different physical activity (age group 15-18 years) including ballet dancers, karate fighters, cross runners as well as adolescents of average physical activity (female and male). The investigation was performed in two series. The first--before intense exercise training and the second--after intense exercise training. In control group there was only one series. Urea was estimated by using urease which converts urea into ammonia, CO2 and glutamic dehydrogenase reaction via measurements of ammonia derived from urea. The amounts of urea were applied for counting quantity of consumed proteins. In the physically active groups the protein intake was too low in comparison to required.

Status of women in physics in China-Taipei from the view of quantity and quality

NASA Astrophysics Data System (ADS)

Lin, Jauyn Grace; Ho, Mon-Shu; Lin, Keng-Ching; Chen, Yi-Chun; Chiu, Ya-Ping; Hu, Shu-Fen; Hsiung, Yee Bob; Chang, Yuan-Huei; Chang, Ching Ray

2013-03-01

The Working Group for Women in Physics in Taiwan was registered to the Physical Society of the Republic of China (PSROC) in December 1999 and was formally announced at the 2001 annual assembly of PSROC. In 2003 the group became a formal committee under PSROC. The current committee includes seven female and two male members. In the last 10 years, many milestones were achieved. In particular, the percentage of female physics faculties in universities and research institutes has increased to 12% from 8% within the last 10 years. In this paper we will present the results of our survey on the changes of the percentage of female physics faculties/students within the last 10 years and express our need to improve the working environment for female faculties in Taiwan in the future.

From see one do one, to see a good one do a better one: learning physical examination skills through peer observation.

PubMed

St-Onge, Christina; Martineau, Bernard; Harvey, Anne; Bergeron, Linda; Mamede, Silvia; Rikers, Remy

2013-01-01

Learning and mastering the skills required to execute physical exams is of great importance and should be fostered early during medical training. Observing peers has been shown to positively influence the acquisition of psychomotor skills. The current study investigated the influence of peer observation on the acquisition of psychomotor skills required to execute a physical examination. Second-year medical students (N=194) learned the neurological physical examination for low back pain in groups of three. Each student learned and performed the physical examination while the other students observed. Analyses compared the impact of the quantity and the quality of observed performances on students' learning of the physical examination skills. Students benefited from observing peers while they executed their examination. Moreover, observing a high-performing peer increased the acquisition of physical examination skills. Results suggest that group learning activities that allow students to observe their peers during physical examination should be favored.

Physical Activity Guidelines

MedlinePlus

... use this site. health.gov Physical Activity Guidelines Physical Activity Physical activity is key to improving the health of the Nation. Based on the latest science, the Physical Activity Guidelines for Americans is an essential resource for ...

Classic Bernoulli's Principle Derivation and Its Working Hypotheses

ERIC Educational Resources Information Center

Marciotto, Edson R.

2016-01-01

The Bernoulli's principle states that the quantity p+ pgz + pv[superscript 2]/2 must be conserved in a streamtube if some conditions are matched, namely: steady and irrotational flow of an inviscid and incompressible fluid. In most physics textbooks this result is demonstrated invoking the energy conservation of a fluid material volume at two…

Toward a Parastatistics in Quantum Nonextensive Statistical Mechanics

NASA Astrophysics Data System (ADS)

Zaripov, R. G.

2018-05-01

On the basis of Bose quantum states in parastatistics the equations for the equilibrium distribution of quantum additive and nonextensive systems are determined. The fluctuations and variances of physical quantities for the equilibrium system are found. The Abelian group of microscopic entropies is determined for the composition law with a quadratic nonlinearity.

The Heart's Content : The Association between Positive Psychological Well-Being and Cardiovascular Health

ERIC Educational Resources Information Center

Boehm, Julia K.; Kubzansky, Laura D.

2012-01-01

This review investigates the association between positive psychological well-being (PPWB) and cardiovascular disease (CVD). We also consider the mechanisms by which PPWB may be linked with CVD, focusing on the health behaviors (e.g., smoking, alcohol consumption, physical activity, sleep quality and quantity, and food consumption) and biological…

A School Experiment in Kinematics: Shooting from a Ballistic Cart

ERIC Educational Resources Information Center

Kranjc, T.; Razpet, N.

2011-01-01

Many physics textbooks start with kinematics. In the lab, students observe the motions, describe and make predictions, and get acquainted with basic kinematics quantities and their meaning. Then they can perform calculations and compare the results with experimental findings. In this paper we describe an experiment that is not often done, but is…

Validating Accelerometry and Skinfold Measures in Youth with Down Syndrome

ERIC Educational Resources Information Center

Esposito, Phil Michael

2012-01-01

Current methods for measuring quantity and intensity of physical activity based on accelerometer output have been studied and validated in youth. These methods have been applied to youth with Down syndrome (DS) with no empirical research done to validate these measures. Similarly, individuals with DS have unique body proportions not represented by…

27 CFR 46.195 - Floor stocks requirements.

Code of Federal Regulations, 2010 CFR

2010-04-01

... Tubes Held for Sale on April 1, 2009 General § 46.195 Floor stocks requirements. (a) Take inventory. The dealer must establish the quantity of articles subject to the floor stocks tax held for sale on April 1, 2009. The dealer may take a physical inventory or may use a record (book) inventory, as specified in...

Never Getting to Zero: Elementary School Students' Understanding of the Infinite Divisibility of Number and Matter

ERIC Educational Resources Information Center

Smith, Carol L.; Solomon, Gregg E. A.; Carey, Susan

2005-01-01

Clinical interviews administered to third- to sixth-graders explored children's conceptualizations of rational number and of certain extensive physical quantities. We found within child consistency in reasoning about diverse aspects of rational number. Children's spontaneous acknowledgement of the existence of numbers between 0 and 1 was strongly…

Michelangelo and the Prevention of Childhood Obesity

ERIC Educational Resources Information Center

Maimon, Martin

2008-01-01

Child care professionals are in a unique position to teach children healthy lifestyle habits. It is not easy, but quality programs are getting it done. One factor that determines the quantity and quality of physical activity in child care settings is the education and training of staff, and learning basic strategies for promoting healthy food…

The Electromagnetic Force between Two Moving Charges

ERIC Educational Resources Information Center

Minkin, Leonid; Shapovalov, Alexander S.

2018-01-01

A simple model of parallel motion of two point charges and the subsequent analysis of the electromagnetic field transformation invariant quantity are considered. It is shown that ignoring the coupling of electric and magnetic fields, as is done in some introductory physics books, can lead to miscalculations of the force between moving charges.…

40 CFR Appendix I to Part 265 - Recordkeeping Instructions

Code of Federal Regulations, 2010 CFR

2010-07-01

... physical form, i.e., liquid, sludge, solid, or contained gas. If the waste is not listed in part 261..., solid filter cake from production of ___, EPA Hazardous Waste Number W051). Each hazardous waste listed... technique(s) used at the facility to treat, store or dispose of each quantity of hazardous waste received. 1...

Determination of the Quantum Efficiency of a Light Detector

ERIC Educational Resources Information Center

Kraftmakher, Yaakov

2008-01-01

The "quantum efficiency" (QE) is an important property of a light detector. This quantity can be determined in the undergraduate physics laboratory. The experimentally determined QE of a silicon photodiode appeared to be in reasonable agreement with expected values. The experiment confirms the quantum properties of light and seems to be a useful…

Real quantum cybernetics

NASA Astrophysics Data System (ADS)

Grössing, Gerhard

1987-05-01

It is shown on the basis of quantum cybernetics that one can obtain the usual predictions of quantum theory without ever referring to complex numbered “quantum mechanical amplitudes”. Instead, a very simple formula for transition and certain conditional probabilities is developed that involves real numbers only, thus relating intuitively understandable and in principle directly observable physical quantities.

Statistical physics when the minimum temperature is not absolute zero

NASA Astrophysics Data System (ADS)

Chung, Won Sang; Hassanabadi, Hassan

2018-04-01

In this paper, the nonzero minimum temperature is considered based on the third law of thermodynamics and existence of the minimal momentum. From the assumption of nonzero positive minimum temperature in nature, we deform the definitions of some thermodynamical quantities and investigate nonzero minimum temperature correction to the well-known thermodynamical problems.

Energy as a Substancelike Quantity That Flows: Theoretical Considerations and Pedagogical Consequences

ERIC Educational Resources Information Center

Brewe, Eric

2011-01-01

Utilizing an energy-as-substance conceptual metaphor as a central feature of the introductory physics curriculum affords students a wealth of conceptual resources for reasoning about energy conservation, storage, and transfer. This paper first establishes the utility and function of a conceptual metaphor in developing student understanding of…

Photocatalytic Oxidation of Sulfurous Acid in an Aqueous Medium

ERIC Educational Resources Information Center

Romero, Alicia; Hernandez, Willie; Suarez, Marco F.

2005-01-01

The effect of some parameters on sulfurous acid and sulfur oxidation kinetics such as initial concentration of sulfurous acid, oxygen, TiO[2] crystalline concentration, the power of black light, and quantity of TiO[2] is investigated. The experiments can be performed in an undergraduate physical chemistry laboratory with an inexpensive…

Simple process-led algorithms for simulating habitats (SPLASH v.1.0): robust indices of radiation, evapotranspiration and plant-available moisture

NASA Astrophysics Data System (ADS)

Davis, Tyler W.; Prentice, I. Colin; Stocker, Benjamin D.; Thomas, Rebecca T.; Whitley, Rhys J.; Wang, Han; Evans, Bradley J.; Gallego-Sala, Angela V.; Sykes, Martin T.; Cramer, Wolfgang

2017-02-01

Bioclimatic indices for use in studies of ecosystem function, species distribution, and vegetation dynamics under changing climate scenarios depend on estimates of surface fluxes and other quantities, such as radiation, evapotranspiration and soil moisture, for which direct observations are sparse. These quantities can be derived indirectly from meteorological variables, such as near-surface air temperature, precipitation and cloudiness. Here we present a consolidated set of simple process-led algorithms for simulating habitats (SPLASH) allowing robust approximations of key quantities at ecologically relevant timescales. We specify equations, derivations, simplifications, and assumptions for the estimation of daily and monthly quantities of top-of-the-atmosphere solar radiation, net surface radiation, photosynthetic photon flux density, evapotranspiration (potential, equilibrium, and actual), condensation, soil moisture, and runoff, based on analysis of their relationship to fundamental climatic drivers. The climatic drivers include a minimum of three meteorological inputs: precipitation, air temperature, and fraction of bright sunshine hours. Indices, such as the moisture index, the climatic water deficit, and the Priestley-Taylor coefficient, are also defined. The SPLASH code is transcribed in C++, FORTRAN, Python, and R. A total of 1 year of results are presented at the local and global scales to exemplify the spatiotemporal patterns of daily and monthly model outputs along with comparisons to other model results.

Denervation-Induced Activation of the Ubiquitin-Proteasome System Reduces Skeletal Muscle Quantity Not Quality.

PubMed

Baumann, Cory W; Liu, Haiming M; Thompson, LaDora V

2016-01-01

It is well known that the ubiquitin-proteasome system is activated in response to skeletal muscle wasting and functions to degrade contractile proteins. The loss of these proteins inevitably reduces skeletal muscle size (i.e., quantity). However, it is currently unknown whether activation of this pathway also affects function by impairing the muscle's intrinsic ability to produce force (i.e., quality). Therefore, the purpose of this study was twofold, (1) document how the ubiquitin-proteasome system responds to denervation and (2) identify the physiological consequences of these changes. To induce soleus muscle atrophy, C57BL6 mice underwent tibial nerve transection of the left hindlimb for 7 or 14 days (n = 6-8 per group). At these time points, content of several proteins within the ubiquitin-proteasome system were determined via Western blot, while ex vivo whole muscle contractility was specifically analyzed at day 14. Denervation temporarily increased several key proteins within the ubiquitin-proteasome system, including the E3 ligase MuRF1 and the proteasome subunits 19S, α7 and β5. These changes were accompanied by reductions in absolute peak force and power, which were offset when expressed relative to physiological cross-sectional area. Contrary to peak force, absolute and relative forces at submaximal stimulation frequencies were significantly greater following 14 days of denervation. Taken together, these data represent two keys findings. First, activation of the ubiquitin-proteasome system is associated with reductions in skeletal muscle quantity rather than quality. Second, shortly after denervation, it appears the muscle remodels to compensate for the loss of neural activity via changes in Ca2+ handling.

Impact of chronic lymphatic filariasis on quantity and quality of productive work among weavers in an endemic village from India.

PubMed

Babu, B V; Swain, B K; Rath, K

2006-05-01

To assess the impact of hydrocele and lymphoedema on the quantity and quality of productive work of weavers. Case-control study in an endemic village in Andhra Pradesh, India. We collected qualitative data on work activities from cases and age- and sex-matched controls through informal discussions and observation. The mean (+/-standard deviation) daily work time of cases was 7.38 h (+/-2.47), significantly less than that of controls (8.17+/-2.41 h). Lost work time was equivalent to around 29 days of work in a year. Gender had significant influence on the mean number of working hours in this occupational group. Most cases could not weave, which is physically demanding, and preferred less strenuous tasks such as spinning, starching, dyeing or sizing. Hard physical labour constitutes 71.5% of total work time among patients and 83.7% in controls. As income also depends on the type of work, cases earn less. Filariasis has an adverse impact on the productivity of weavers, and morbidity management strategies and control programmes need to take this into account.

Below-ground process responses to elevated CO2 and temperature: a discussion of observations, measurement methods, and models

Treesearch

Elise Pendall; Scott Bridgham; Paul J. Hanson; Bruce Hungate; David W. Kicklighter; Dale W. Johnson; Beverly E. Law; Yiqi Luo; J. Patrick Megonigal; Maria Olsrud; Michael G. Ryan; Shiqiang Wan

2004-01-01

Rising atmospheric CO2 and temperatures are probably altering ecosystem carbon cycling, causing both positive and negative feedbacks to climate. Below-ground processes play a key role in the global carbon (C) cycle because they regulate storage of large quantities of C, and are potentially very sensitive to direct and indirect effects of elevated...

Fruit production in mature and recently regenerated forests of the Appalachians

Treesearch

Cathryn H. Greenberg; Douglas J. Levey; David L. Loftis

2007-01-01

Fleshy fruit is a key food resource for both game and nongame wildlife, and it may be especially important for migratory birds during fall and for resident birds and mammals during winter. Land managers need to know how land uses affect the quantities and species of fruit produced in different forest types and how fruit production varies seasonally and as young stands...

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wu, C

Purpose: To implement a novel, automatic, institutional customizable DVH quantities evaluation and PDF report tool on Philips Pinnacle treatment planning system (TPS) Methods: An add-on program (P3DVHStats) is developed by us to enable automatic DVH quantities evaluation (including both volume and dose based quantities, such as V98, V100, D2), and automatic PDF format report generation, for EMR convenience. The implementation is based on a combination of Philips Pinnacle scripting tool and Java language pre-installed on each Pinnacle Sun Solaris workstation. A single Pinnacle script provide user a convenient access to the program when needed. The activated script will first exportmore » DVH data for user selected ROIs from current Pinnacle plan trial; a Java program then provides a simple GUI interface, utilizes the data to compute any user requested DVH quantities, compare with preset institutional DVH planning goals; if accepted by users, the program will also generate a PDF report of the results and export it from Pinnacle to EMR import folder via FTP. Results: The program was tested thoroughly and has been released for clinical use at our institution (Pinnacle Enterprise server with both thin clients and P3PC access), for all dosimetry and physics staff, with excellent feedback. It used to take a few minutes to use MS-Excel worksheet to calculate these DVH quantities for IMRT/VMAT plans, and manually save them as PDF report; with the new program, it literally takes a few mouse clicks in less than 30 seconds to complete the same tasks. Conclusion: A Pinnacle scripting and Java language based program is successfully implemented, customized to our institutional needs. It is shown to dramatically reduce time and effort needed for DVH quantities computing and EMR reporting.« less

The home physical environment and its relationship with physical activity and sedentary behavior: a systematic review.

PubMed

Kaushal, Navin; Rhodes, Ryan E

2014-10-01

Reviews of neighborhood (macro) environment characteristics such as the presence of sidewalks and esthetics have shown significant correlations with resident physical activity (PA) and sedentary (SD) behavior. Currently, no comprehensive review has appraised and collected available evidence on the home (micro) physical environment. The purpose of this review was to examine how the home physical environment relates to adult and child PA and SD behaviors. Articles were searched during May 2014 using Medline, PsycINFO, PubMed, Scopus, and SPORTDiscus databases which yielded 3265 potential studies. Papers were considered eligible if they investigated the presence of PA (ie. exercise equipment, exergaming devices) or SD (ie. television, videogames) equipment and PA or SD behavior. After, screening and manual cross-referencing, 49 studies (20 experimental and 29 observational designs) were found to meet the eligibility criteria. Interventions that reduced sedentary time by using TV limiting devices were shown to be effective for children but the results were limited for adults. Overall, large exercise equipment (ie. treadmills), and prominent exergaming materials (exergaming bike, dance mats) were found to be more effective than smaller devices. Observational studies revealed that location and quantity of televisions correlated with SD behavior with the latter having a greater effect on girls. This was similarly found for the quantity of PA equipment which also correlated with behavior in females. Given the large market for exercise equipment, videos and exergaming, the limited work performed on its effectiveness in homes is alarming. Future research should focus on developing stronger randomized controlled trials, investigate the location of PA equipment, and examine mediators of the gender discrepancy found in contemporary studies. Copyright © 2014 Elsevier Inc. All rights reserved.

The influence of physical activity on the profile of immune response cells and cytokine synthesis in mice with experimental breast tumors induced by 7,12-dimethylbenzanthracene.

PubMed

Abdalla, Douglas R; Murta, Eddie F C; Michelin, Márcia A

2013-05-01

This study aims to investigate cytokine synthesis by lymphocytes in the presence of mammary tumors and the interaction with physical activity. For this study, we used 56 female Balb/c, 8-week-old, virgin mice with a body mass between 20 and 30 g. The mice were divided into four groups: a no tumor/nontrained control group; a no tumor/trained group subjected to physical training of swimming in water (30 ± 4°C) for 45 min, five times per week for 8 weeks; a tumor/nontrained (sedentary) group in which the animals received 7,12-dimethylbenzanthracene [(DMBA) 1 mg/ml weekly for 6 weeks)]; and a tumor/trained group in which animals were subjected to the aforementioned DMBA tumor induction and swim training protocols. After the experimental period, immune cells were collected from spleen cell specimens, placed in culture, and stimulated with lipopolysaccharide. The presence of cluster of differentiation (CD)3, CD4, and CD8 markers and the expression of interferon-γ, interleukin (IL)-2, IL-4, IL-10, IL-12, transforming growth factor β, and tumor necrosis factor α cytokines were assessed by flow cytometry and enzyme-linked immunosorbent assay. Physical activity increased the quantities of lymphocytes producing interferon γ, IL-2, IL-12, and tumor necrosis factor α and decreased the quantities of lymphocytes and macrophages expressing IL-4, IL-10, and transforming growth factor β. In contrast, tumor induction, in the absence of swim training, reduced Th1 cytokine levels while increasing the presence of Th2 cytokines and Treg cells. Physical activity promoted reductions in the incidence of tumor development and promoted immune system polarization toward an antitumor Th1 response pattern profile.

[Features of PHITS and its application to medical physics].

PubMed

Hashimoto, Shintaro; Niita, Koji; Matsuda, Norihiro; Iwamoto, Yosuke; Iwase, Hiroshi; Sato, Tatsuhiko; Noda, Shusaku; Ogawa, Tatsuhiko; Nakashima, Hiroshi; Fukahori, Tokio; Furuta, Takuya; Chiba, Satoshi

2013-01-01

PHITS is a general purpose Monte Carlo particle transport simulation code to analyze the transport in three-dimensional phase space and collisions of nearly all particles, including heavy ions, over wide energy range up to 100 GeV/u. Various quantities, such as particle fluence and deposition energies in materials, can be deduced using estimator functions "tally". Recently, a microdosimetric tally function was also developed to apply PHITS to medical physics. Owing to these features, PHITS has been used for medical applications, such as radiation therapy and protection.

Do the repulsive and attractive pair forces play separate roles for the physics of liquids?

PubMed

Bøhling, Lasse; Veldhorst, Arno A; Ingebrigtsen, Trond S; Bailey, Nicholas P; Hansen, Jesper S; Toxvaerd, Søren; Schrøder, Thomas B; Dyre, Jeppe C

2013-01-23

According to standard liquid-state theory repulsive and attractive pair forces play distinct roles for the physics of liquids. This paradigm is put into perspective here by demonstrating a continuous series of pair potentials that have virtually the same structure and dynamics, although only some of them have attractive forces of significance. Our findings reflect the fact that the motion of a given particle is determined by the total force on it, whereas the quantity usually discussed in liquid-state theory is the individual pair force.

Theoretical atomic physics code development I: CATS: Cowan Atomic Structure Code

DOE Office of Scientific and Technical Information (OSTI.GOV)

Abdallah, J. Jr.; Clark, R.E.H.; Cowan, R.D.

An adaptation of R.D. Cowan's Atomic Structure program, CATS, has been developed as part of the Theoretical Atomic Physics (TAPS) code development effort at Los Alamos. CATS has been designed to be easy to run and to produce data files that can interface with other programs easily. The CATS produced data files currently include wave functions, energy levels, oscillator strengths, plane-wave-Born electron-ion collision strengths, photoionization cross sections, and a variety of other quantities. This paper describes the use of CATS. 10 refs.

(Super)symmetries of semiclassical models in theoretical and condensed matter physics

NASA Astrophysics Data System (ADS)

Ngome, J.-P.

2011-03-01

Van Holten's covariant algorithm for deriving conserved quantities is presented, with particular attention paid to Runge-Lenz-type vectors. The classical dynamics of isospin-carrying particles is reviewed. Physical applications including non-Abelian monopole-type systems in diatoms, introduced by Moody, Shapere and Wilczek, are considered. Applied to curved space, the formalism of van Holten allows us to describe the dynamical symmetries of generalized Kaluza-Klein monopoles. The framework is extended to supersymmetry and applied to the SUSY of the monopoles. Yet another application concerns the three-dimensional non-commutative oscillator.

Instrumentation, metrology, and standards: key elements for the future of nanomanufacturing

NASA Astrophysics Data System (ADS)

Postek, Michael T.; Lyons, Kevin

2007-09-01

Nanomanufacturing is the essential bridge between the discoveries of nanoscience and real world nanotech products and is the vehicle by which the Nation and the World will realize the promise of major technological innovation across a spectrum of products that will affect virtually every industrial sector. For nanotech products to achieve the broad impacts envisioned, they must be manufactured in market-appropriate quantities in a reliable, repeatable, economical and commercially viable manner. In addition, they must be manufactured so that environmental and human health concerns are met, worker safety issues are appropriately assessed and handled, and liability issues are addressed. Critical to this realization of robust nanomanufacturing is the development of the necessary instrumentation, metrology, and standards. Integration of the instruments, their interoperability, and appropriate information management are also critical elements that must be considered for viable nanomanufacturing. Advanced instrumentation, metrology and standards will allow the physical dimensions, properties, functionality, and purity of the materials, processes, tools, systems, products, and emissions that will constitute nanomanufacturing to be measured and characterized. This will in turn enable production to be scaleable, controllable, predictable, and repeatable to meet market needs. If a nano-product cannot be measured it cannot be manufactured; additionally if that product cannot be made safely it should not be manufactured. This presentation introduces the Instrumentation, Metrology, and Standards for Nanomanufacturing Conference at the 2007 SPIE Optics and Photonics. This conference will become the leading forum for the exchange of foundational information and discussion of instrumentation, metrology and standards which are key elements for the success of nanomanufacturing.

Use of focused acoustics for cell disruption to provide ultra scale-down insights of microbial homogenization and its bioprocess impact--recovery of antibody fragments from rec E. coli.

PubMed

Li, Qiang; Aucamp, Jean P; Tang, Alison; Chatel, Alex; Hoare, Mike

2012-08-01

An ultra scale-down (USD) device that provides insight of how industrial homogenization impacts bioprocess performance is desirable in the biopharmaceutical industry, especially at the early stage of process development where only a small quantity of material is available. In this work, we assess the effectiveness of focused acoustics as the basis of an USD cell disruption method to mimic and study high-pressure, step-wise homogenization of rec Escherichia coli cells for the recovery of an intracellular protein, antibody fragment (Fab'). The release of both Fab' and of overall protein follows first-order reaction kinetics with respect to time of exposure to focused acoustics. The rate constant is directly proportional to applied electrical power input per unit volume. For nearly total protein or Fab' release (>99%), the key physical properties of the disruptate produced by focused acoustics, such as cell debris particle size distribution and apparent viscosity show good agreement with those for homogenates produced by high-pressure homogenization operated to give the same fractional release. The only key difference is observed for partial disruption of cells where focused acoustics yields a disruptate of lower viscosity than homogenization, evidently due to a greater extent of polynucleic acids degradation. Verification of this USD approach to cell disruption by high-pressure homogenization is achieved using USD centrifugation to demonstrate the same sedimentation characteristics of disruptates prepared using both the scaled-down focused acoustic and the pilot-scale homogenization methods for the same fraction of protein release. Copyright © 2012 Wiley Periodicals, Inc.

Gut microbiota composition in male rat models under different nutritional status and physical activity and its association with serum leptin and ghrelin levels.

PubMed

Queipo-Ortuño, María Isabel; Seoane, Luisa María; Murri, Mora; Pardo, María; Gomez-Zumaquero, Juan Miguel; Cardona, Fernando; Casanueva, Felipe; Tinahones, Francisco J

2013-01-01

Several evidences indicate that gut microbiota is involved in the control of host energy metabolism. To evaluate the differences in the composition of gut microbiota in rat models under different nutritional status and physical activity and to identify their associations with serum leptin and ghrelin levels. In a case control study, forty male rats were randomly assigned to one of these four experimental groups: ABA group with food restriction and free access to exercise; control ABA group with food restriction and no access to exercise; exercise group with free access to exercise and feed ad libitum and ad libitum group without access to exercise and feed ad libitum. The fecal bacteria composition was investigated by PCR-denaturing gradient gel electrophoresis and real-time qPCR. In restricted eaters, we have found a significant increase in the number of Proteobacteria, Bacteroides, Clostridium, Enterococcus, Prevotella and M. smithii and a significant decrease in the quantities of Actinobacteria, Firmicutes, Bacteroidetes, B. coccoides-E. rectale group, Lactobacillus and Bifidobacterium with respect to unrestricted eaters. Moreover, a significant increase in the number of Lactobacillus, Bifidobacterium and B. coccoides-E. rectale group was observed in exercise group with respect to the rest of groups. We also found a significant positive correlation between the quantity of Bifidobacterium and Lactobacillus and serum leptin levels, and a significant and negative correlation among the number of Clostridium, Bacteroides and Prevotella and serum leptin levels in all experimental groups. Furthermore, serum ghrelin levels were negatively correlated with the quantity of Bifidobacterium, Lactobacillus and B. coccoides-Eubacterium rectale group and positively correlated with the number of Bacteroides and Prevotella. Nutritional status and physical activity alter gut microbiota composition affecting the diversity and similarity. This study highlights the associations between gut microbiota and appetite-regulating hormones that may be important in terms of satiety and host metabolism.

Gut Microbiota Composition in Male Rat Models under Different Nutritional Status and Physical Activity and Its Association with Serum Leptin and Ghrelin Levels

PubMed Central

Queipo-Ortuño, María Isabel; Seoane, Luisa María; Murri, Mora; Pardo, María; Gomez-Zumaquero, Juan Miguel; Cardona, Fernando; Casanueva, Felipe; Tinahones, Francisco J.

2013-01-01

Background Several evidences indicate that gut microbiota is involved in the control of host energy metabolism. Objective To evaluate the differences in the composition of gut microbiota in rat models under different nutritional status and physical activity and to identify their associations with serum leptin and ghrelin levels. Methods In a case control study, forty male rats were randomly assigned to one of these four experimental groups: ABA group with food restriction and free access to exercise; control ABA group with food restriction and no access to exercise; exercise group with free access to exercise and feed ad libitum and ad libitum group without access to exercise and feed ad libitum. The fecal bacteria composition was investigated by PCR-denaturing gradient gel electrophoresis and real-time qPCR. Results In restricted eaters, we have found a significant increase in the number of Proteobacteria, Bacteroides, Clostridium, Enterococcus, Prevotella and M. smithii and a significant decrease in the quantities of Actinobacteria, Firmicutes, Bacteroidetes, B. coccoides-E. rectale group, Lactobacillus and Bifidobacterium with respect to unrestricted eaters. Moreover, a significant increase in the number of Lactobacillus, Bifidobacterium and B. coccoides–E. rectale group was observed in exercise group with respect to the rest of groups. We also found a significant positive correlation between the quantity of Bifidobacterium and Lactobacillus and serum leptin levels, and a significant and negative correlation among the number of Clostridium, Bacteroides and Prevotella and serum leptin levels in all experimental groups. Furthermore, serum ghrelin levels were negatively correlated with the quantity of Bifidobacterium, Lactobacillus and B. coccoides–Eubacterium rectale group and positively correlated with the number of Bacteroides and Prevotella. Conclusions Nutritional status and physical activity alter gut microbiota composition affecting the diversity and similarity. This study highlights the associations between gut microbiota and appetite-regulating hormones that may be important in terms of satiety and host metabolism. PMID:23724144

Probing the physics of newly born magnetars through observation of superluminous supernovae

NASA Astrophysics Data System (ADS)

Cheng, Quan; Zhang, Shuang-Nan; Yu, Yun-Wei; Zheng, Xiao-Ping

2018-05-01

The central engines of some superluminous supernovae (SLSNe) are generally suggested to be newly born fast rotating magnetars, which spin down mainly through magnetic dipole radiation and gravitational wave emission. We calculate the magnetar-powered SLSNe light curves (LCs) with the tilt angle evolution of newly born magnetars involved. We show that, depending on the internal toroidal magnetic fields B¯t, the initial spin periods Pi, and the radii RDU of direct Urca (DU) cores of newly born magnetars, as well as the critical temperature Tc for 3P2 neutron superfluidity, bumps could appear in the SLSNe LCs after the maximum lights when the tilt angles grow to π /2 . The value of Tc determines the arising time and the relative amplitude of a bump. The quantity RDU can affect the arising time and the luminosity of a bump, as well as the peak luminosity of a LC. For newly born magnetars with dipole magnetic fields Bd=5 ×1014 G , B¯t=4.6 ×1016 G , and Pi=1 ms , there are no bumps in the LCs if Tc=2 ×109 K , or RDU=1.5 ×105 cm . Moreover, it is interesting that a stronger B¯t will lead to both a brighter peak and a brighter bump in a LC. While keeping other quantities unchanged, the bump in the LC disappears for the magnetar with smaller Pi. We suggest that, once the SLSNe LCs with such kinds of bumps are observed, by fitting these LCs with our model, not only Bd and Pi of newly born magnetars but also the crucial physical quantities B¯t, RDU, and Tc could be determined. Nonobservation of SLSNe LCs with such kinds of bumps hitherto may already put some (though very rough) constraints on B¯t, Pi, RDU, and Tc. Therefore, observation of SLSNe LCs may provide a new approach to probe the physics of newly born magnetars.

Anisotropic charged generalized polytropic models

NASA Astrophysics Data System (ADS)

Nasim, A.; Azam, M.

2018-06-01

In this paper, we found some new anisotropic charged models admitting generalized polytropic equation of state with spherically symmetry. An analytic solution of the Einstein-Maxwell field equations is obtained through the transformation introduced by Durgapal and Banerji (Phys. Rev. D 27:328, 1983). The physical viability of solutions corresponding to polytropic index η =1/2, 2/3, 1, 2 is analyzed graphically. For this, we plot physical quantities such as radial and tangential pressure, anisotropy, speed of sound which demonstrated that these models achieve all the considerable physical conditions required for a relativistic star. Further, it is mentioned here that previous results for anisotropic charged matter with linear, quadratic and polytropic equation of state can be retrieved.

Health: The No-Man's-Land Between Physics and Biology.

PubMed

Mansfield, Peter J

2015-10-01

Health as a positive attribute is poorly understood because understanding requires concepts from physics, of which physicians and other life scientists have a very poor grasp. This paper reviews the physics that bears on biology, in particular complex quaternions and scalar fields, relates these to the morphogenetic fields proposed by biologists, and defines health as an attribute of living action within these fields. The distinction of quality, as juxtaposed with quantity, proves essential. Its basic properties are set out, but a science and mathematics of quality are awaited. The implications of this model are discussed, particularly as proper health enhancement could set a natural limit to demand for, and therefore the cost of, medical services.

Parallel Grid Manipulations in Earth Science Calculations

NASA Technical Reports Server (NTRS)

Sawyer, W.; Lucchesi, R.; daSilva, A.; Takacs, L. L.

1999-01-01

The National Aeronautics and Space Administration (NASA) Data Assimilation Office (DAO) at the Goddard Space Flight Center is moving its data assimilation system to massively parallel computing platforms. This parallel implementation of GEOS DAS will be used in the DAO's normal activities, which include reanalysis of data, and operational support for flight missions. Key components of GEOS DAS, including the gridpoint-based general circulation model and a data analysis system, are currently being parallelized. The parallelization of GEOS DAS is also one of the HPCC Grand Challenge Projects. The GEOS-DAS software employs several distinct grids. Some examples are: an observation grid- an unstructured grid of points at which observed or measured physical quantities from instruments or satellites are associated- a highly-structured latitude-longitude grid of points spanning the earth at given latitude-longitude coordinates at which prognostic quantities are determined, and a computational lat-lon grid in which the pole has been moved to a different location to avoid computational instabilities. Each of these grids has a different structure and number of constituent points. In spite of that, there are numerous interactions between the grids, e.g., values on one grid must be interpolated to another, or, in other cases, grids need to be redistributed on the underlying parallel platform. The DAO has designed a parallel integrated library for grid manipulations (PILGRIM) to support the needed grid interactions with maximum efficiency. It offers a flexible interface to generate new grids, define transformations between grids and apply them. Basic communication is currently MPI, however the interfaces defined here could conceivably be implemented with other message-passing libraries, e.g., Cray SHMEM, or with shared-memory constructs. The library is written in Fortran 90. First performance results indicate that even difficult problems, such as above-mentioned pole rotation- a sparse interpolation with little data locality between the physical lat-lon grid and a pole rotated computational grid- can be solved efficiently and at the GFlop/s rates needed to solve tomorrow's high resolution earth science models. In the subsequent presentation we will discuss the design and implementation of PILGRIM as well as a number of the problems it is required to solve. Some conclusions will be drawn about the potential performance of the overall earth science models on the supercomputer platforms foreseen for these problems.

"Untapped Potential?" Key Competency Learning and Physical Education

ERIC Educational Resources Information Center

Gillespie, Lorna; Penney, Dawn; Pope, Clive

2013-01-01

This paper reports on a collaborative action research project that directed attention to the opportunities Physical Education presents to develop learning associated with three of the key competencies detailed in the New Zealand Curriculum; thinking; managing self; and relating to others. Three teachers in one secondary school explored the…

Continuous-variable quantum authentication of physical unclonable keys

NASA Astrophysics Data System (ADS)

Nikolopoulos, Georgios M.; Diamanti, Eleni

2017-04-01

We propose a scheme for authentication of physical keys that are materialized by optical multiple-scattering media. The authentication relies on the optical response of the key when probed by randomly selected coherent states of light, and the use of standard wavefront-shaping techniques that direct the scattered photons coherently to a specific target mode at the output. The quadratures of the electromagnetic field of the scattered light at the target mode are analysed using a homodyne detection scheme, and the acceptance or rejection of the key is decided upon the outcomes of the measurements. The proposed scheme can be implemented with current technology and offers collision resistance and robustness against key cloning.

Multi-Scale Distributed Representation for Deep Learning and its Application to b-Jet Tagging

NASA Astrophysics Data System (ADS)

Lee, Jason Sang Hun; Park, Inkyu; Park, Sangnam

2018-06-01

Recently machine learning algorithms based on deep layered artificial neural networks (DNNs) have been applied to a wide variety of high energy physics problems such as jet tagging or event classification. We explore a simple but effective preprocessing step which transforms each realvalued observational quantity or input feature into a binary number with a fixed number of digits. Each binary digit represents the quantity or magnitude in different scales. We have shown that this approach improves the performance of DNNs significantly for some specific tasks without any further complication in feature engineering. We apply this multi-scale distributed binary representation to deep learning on b-jet tagging using daughter particles' momenta and vertex information.

Observation model and parameter partials for the JPL geodetic (GPS) modeling software 'GPSOMC'

NASA Technical Reports Server (NTRS)

Sovers, O. J.

1990-01-01

The physical models employed in GPSOMC, the modeling module of the GIPSY software system developed at JPL for analysis of geodetic Global Positioning Satellite (GPS) measurements are described. Details of the various contributions to range and phase observables are given, as well as the partial derivatives of the observed quantities with respect to model parameters. A glossary of parameters is provided to enable persons doing data analysis to identify quantities with their counterparts in the computer programs. The present version is the second revision of the original document which it supersedes. The modeling is expanded to provide the option of using Cartesian station coordinates; parameters for the time rates of change of universal time and polar motion are also introduced.

Temperature and composition dependence of the refractive indices of the 2-chloroethanol + 2-methoxyethanol binary mixtures.

PubMed

Cocchi, Marina; Manfredini, Matteo; Marchetti, Andrea; Pigani, Laura; Seeber, Renato; Tassi, Lorenzo; Ulrici, Alessandro; Vignali, Moris; Zanardi, Chiara; Zannini, Paolo

2002-03-01

Measurements of the refractive index n for the binary mixtures 2-chloroethanol + 2-methoxyethanol in the 0 < or = t/degree C < or = 70 temperature range have been carried out with the purpose of checking the capability of empirical models to express physical quantity as a function of temperature and volume fraction, both separately and together, i.e., in a two independent variables expression. Furthermore, the experimental data have been used to calculate excess properties such as the excess refractive index, the excess molar refraction, and the excess Kirkwood parameter delta g over the whole composition range. The quantities obtained have been discussed and interpreted in terms of the type and nature of the specific intermolecular interactions between the components.

Modeling the Self-Organized Critical Behavior of Earth's Plasma Sheet Reconnection Dynamics

NASA Astrophysics Data System (ADS)

Klimas, A.; Uritsky, V.; Baker, D.

2006-05-01

Analyses of Polar UVI auroral image data (Uritsky et al. JGR, 2002; GRL, 2003, 2006) show that bright night- side high-latitude UV emissions exhibit so many of the key properties of systems in self-organized criticality that an alternate interpretation has become virtually impossible. It is now necessary to find and model the source of this behavior. We note that the most common models of self-organized criticality are numerical sandpiles. These are, at root, models that govern the transport of some quantity from a region where it is loaded to another where it is unloaded. Transport is enabled by the excitation of a local threshold instability; it is intermittent and bursty, and it exhibits a number of scale-free statistical properties. Searching for a system in the magnetosphere that is analogous and that, in addition, is known to produce auroral signatures, we focus on the reconnection dynamics of the plasma sheet. In our previous work, a driven reconnection model has been constructed and has been under study (Klimas et al. JGR, 2004; GRL 2005). The transport of electromagnetic (primarily magnetic) energy carried by the Poynting flux into the reconnection region of the model has been examined. All of the analysis techniques, and more, that have been applied to the auroral image data have also been applied to this Poynting flux. Here, we report new results showing that this model also exhibits so many of the key properties of systems in self-organized criticality that an alternate interpretation is implausible. Further, we find a strong correlation between these key properties of the model and those of the auroral UV emissions. We suggest that, in general, the driven reconnection model is an important step toward a realistic plasma physical model of self-organized criticality and we conclude, more specifically, that it is also a step in the right direction toward modeling the multiscale reconnection dynamics of the magnetotail.