These are representative sample records from Science.gov related to your search topic.
For comprehensive and current results, perform a real-time search at Science.gov.
1

Fourier spectrum based extraction of an equivalent trap state density in indium gallium zinc oxide transistors  

SciTech Connect

Segregating the dynamics of gate bias induced threshold voltage shift, and in particular, charge trapping in thin film transistors (TFTs) based on time constants provides insight into the different mechanisms underlying TFTs instability. In this Letter we develop a representation of the time constants and model the magnitude of charge trapped in the form of an equivalent density of created trap states. This representation is extracted from the Fourier spectrum of the dynamics of charge trapping. Using amorphous In-Ga-Zn-O TFTs as an example, the charge trapping was modeled within an energy range of ?E{sub t}? 0.3?eV and with a density of state distribution as D{sub t}(E{sub t?j})=D{sub t0}exp(??E{sub t}/kT)with D{sub t0}?=?5.02 × 10{sup 11} cm{sup ?2}?eV{sup ?1}. Such a model is useful for developing simulation tools for circuit design.

Thakur, Bikash; Sambandan, Sanjiv, E-mail: sanjiv@iap.iisc.ernet.in [Department of Instrumentation and Applied Physics, Indian Institute of Science, Bangalore 560075 (India); Lee, Sungsik; Nathan, Arokia, E-mail: an299@cam.ac.uk [Electrical Engineering Division, Department of Engineering, University of Cambridge, Cambridge CB3 0FA (United Kingdom); Ahnood, Arman [School of Physics, University of Melbourne, Parkville 3010 VIC (Australia); Jeon, Sanghun, E-mail: jeonsh@korea.ac.kr [Department of Applied Physics, Korea University, 2511 Sejong-ro, Sejong-si 339-700 (Korea, Republic of)

2014-05-19

2

Classification of motor imagery tasks for brain-computer interface applications by means of two equivalent dipoles analysis  

Microsoft Academic Search

We have developed a novel approach using source analysis for classifying motor imagery tasks. Two-equivalent-dipoles analysis was proposed to aid classification of motor imagery tasks for brain-computer interface (BCI) applications. By solving the electroencephalography (EEG) inverse problem of single trial data, it is found that the source analysis approach can aid classification of motor imagination of left- or right-hand movement

Baharan Kamousi; Zhongming Liu; Bin He

2005-01-01

3

Moderate Intense Physical Activity Depends on Selected Metabolic Equivalent of Task (MET) Cut-Off and Type of Data Analysis  

PubMed Central

Background Accelerometry data are frequently analyzed without considering whether moderate-to-vigorous physical activities (MVPA) were performed in bouts of >10 minutes as defined in most physical activity guidelines. We aimed i) to quantify MVPA by using different commonly-applied physical activity guidelines, ii) to investigate the effect of bouts versus non-bouts analysis, and iii) to propose and validate a MVPA non-bouts cut-point to classify (in-) active subjects. Methods Healthy subjects (n=110;62±6yrs) and patients with Chronic Obstructive Pulmonary Disease (COPD) (n=113;62±5yrs) wore an activity monitor for 7 days. Three Metabolic Equivalent of Task (MET) cut-offs and one individual target (50% VO2 reserve) were used to define MVPA. First, all minutes of MVPA were summed up (NON-BOUTS). Secondly, only minutes performed in bouts of >10 minutes continuous activity were counted (BOUTS). Receiver operating characteristic (ROC) curve analyses were used to propose and (cross-) validate new MVPA non-bout cut-points based on the criterion of 30 minutes MVPA per day (BOUTS). Likelihood ratios (sensitivity/[1-specificity]) were used to express the association between the proposed MVPA non-bout target and the MVPA bout target of 30 min*day-1. Results MVPA was variable across physical activity guidelines with lowest values for age-specific cut-offs. Selecting a METs cut-point corresponding to 50% VO2 reserve revealed no differences in MVPA between groups. MVPA’s analyzed in BOUTS in healthy subjects were 2 to 4 fold lower than NON-BOUTS analyses and this was even 3 to 12 fold lower in COPD. The MVPA non-bouts cut-point of 80 min*day-1 using a 3 METs MVPA threshold delivered positive likelihood ratios of 5.1[1.5-19.6] (healthy subjects) and 2.3[1.6-3.3] (COPD). Conclusion MVPA varies upon the selected physical activity guideline/targets and bouts versus non-bouts analysis. Accelerometry measured MVPA non-bouts target of 80 min*day-1, using a 3 METs MVPA threshold, is associated to the commonly-used MVPA bout target of 30 min*day-1. PMID:24376804

Langer, Daniel; Hornikx, Miek; Demeyer, Heleen; Burtin, Chris; Decramer, Marc; Gosselink, Rik; Janssens, Wim; Troosters, Thierry

2013-01-01

4

The reliability and validity of a lift simulator and its functional equivalence with free weight lifting tasks  

Microsoft Academic Search

The combination of Workers' Compensation legal claims and the enactment of the Americans with Disabilities Act (1990) has created a need for more objective and realistic trunk muscle testing. The LIDOLift (Loredan, Inc.) is a computerized dynamometer which has the capabilities to test multijoint coordinated lifting tasks in isometric, isokinetic, and isoinertial modes of operation. The calibration of the electromechanical

Patrick J. Sparto; Mohamad Parnianpour; Kinda A. Khalaf; Sheldon R. Simon

1995-01-01

5

Trapped antihydrogen  

NASA Astrophysics Data System (ADS)

Precision spectroscopic comparison of hydrogen and antihydrogen holds the promise of a sensitive test of the Charge-Parity-Time theorem and matter-antimatter equivalence. The clearest path towards realising this goal is to hold a sample of antihydrogen in an atomic trap for interrogation by electromagnetic radiation. Achieving this poses a huge experimental challenge, as state-of-the-art magnetic-minimum atom traps have well depths of only ˜1 T (˜0.5 K for ground state antihydrogen atoms). The atoms annihilate on contact with matter and must be `born' inside the magnetic trap with low kinetic energies. At the ALPHA experiment, antihydrogen atoms are produced from antiprotons and positrons stored in the form of non-neutral plasmas, where the typical electrostatic potential energy per particle is on the order of electronvolts, more than 104 times the maximum trappable kinetic energy. In November 2010, ALPHA published the observation of 38 antiproton annihilations due to antihydrogen atoms that had been trapped for at least 172 ms and then released—the first instance of a purely antimatter atomic system confined for any length of time (Andresen et al., Nature 468:673, 2010). We present a description of the main components of the ALPHA traps and detectors that were key to realising this result. We discuss how the antihydrogen atoms were identified and how they were discriminated from the background processes. Since the results published in Andresen et al. (Nature 468:673, 2010), refinements in the antihydrogen production technique have allowed many more antihydrogen atoms to be trapped, and held for much longer times. We have identified antihydrogen atoms that have been trapped for at least 1,000 s in the apparatus (Andresen et al., Nature Physics 7:558, 2011). This is more than sufficient time to interrogate the atoms spectroscopically, as well as to ensure that they have relaxed to their ground state.

Butler, E.; Andresen, G. B.; Ashkezari, M. D.; Baquero-Ruiz, M.; Bertsche, W.; Bowe, P. D.; Cesar, C. L.; Chapman, S.; Charlton, M.; Deller, A.; Eriksson, S.; Fajans, J.; Friesen, T.; Fujiwara, M. C.; Gill, D. R.; Gutierrez, A.; Hangst, J. S.; Hardy, W. N.; Hayden, M. E.; Humphries, A. J.; Hydomako, R.; Jenkins, M. J.; Jonsell, S.; Jørgensen, L. V.; Kemp, S. L.; Kurchaninov, L.; Madsen, N.; Menary, S.; Nolan, P.; Olchanski, K.; Olin, A.; Povilus, A.; Pusa, P.; Rasmussen, C. Ø.; Robicheaux, F.; Sarid, E.; Seif el Nasr, S.; Silveira, D. M.; So, C.; Storey, J. W.; Thompson, R. I.; van der Werf, D. P.; Wurtele, J. S.; Yamazaki, Y.

2012-12-01

6

Trapped antihydrogen  

NASA Astrophysics Data System (ADS)

Precision spectroscopic comparison of hydrogen and antihydrogen holds the promise of a sensitive test of the Charge-Parity-Time theorem and matter-antimatter equivalence. The clearest path towards realising this goal is to hold a sample of antihydrogen in an atomic trap for interrogation by electromagnetic radiation. Achieving this poses a huge experimental challenge, as state-of-the-art magnetic-minimum atom traps have well depths of only ˜1 T (˜0.5 K for ground state antihydrogen atoms). The atoms annihilate on contact with matter and must be `born' inside the magnetic trap with low kinetic energies. At the ALPHA experiment, antihydrogen atoms are produced from antiprotons and positrons stored in the form of non-neutral plasmas, where the typical electrostatic potential energy per particle is on the order of electronvolts, more than 104 times the maximum trappable kinetic energy. In November 2010, ALPHA published the observation of 38 antiproton annihilations due to antihydrogen atoms that had been trapped for at least 172 ms and then released—the first instance of a purely antimatter atomic system confined for any length of time (Andresen et al., Nature 468:673, 2010). We present a description of the main components of the ALPHA traps and detectors that were key to realising this result. We discuss how the antihydrogen atoms were identified and how they were discriminated from the background processes. Since the results published in Andresen et al. (Nature 468:673, 2010), refinements in the antihydrogen production technique have allowed many more antihydrogen atoms to be trapped, and held for much longer times. We have identified antihydrogen atoms that have been trapped for at least 1,000 s in the apparatus (Andresen et al., Nature Physics 7:558, 2011). This is more than sufficient time to interrogate the atoms spectroscopically, as well as to ensure that they have relaxed to their ground state.

Butler, E.; Andresen, G. B.; Ashkezari, M. D.; Baquero-Ruiz, M.; Bertsche, W.; Bowe, P. D.; Cesar, C. L.; Chapman, S.; Charlton, M.; Deller, A.; Eriksson, S.; Fajans, J.; Friesen, T.; Fujiwara, M. C.; Gill, D. R.; Gutierrez, A.; Hangst, J. S.; Hardy, W. N.; Hayden, M. E.; Humphries, A. J.; Hydomako, R.; Jenkins, M. J.; Jonsell, S.; Jørgensen, L. V.; Kemp, S. L.; Kurchaninov, L.; Madsen, N.; Menary, S.; Nolan, P.; Olchanski, K.; Olin, A.; Povilus, A.; Pusa, P.; Rasmussen, C. Ø.; Robicheaux, F.; Sarid, E.; Seif el Nasr, S.; Silveira, D. M.; So, C.; Storey, J. W.; Thompson, R. I.; van der Werf, D. P.; Wurtele, J. S.; Yamazaki, Y.

7

Storm- and tide-dominated shorelines in Cretaceous Moosebar-lower Gates interval-outcrop equivalents of Deep basin gas trap in western Canada  

SciTech Connect

The Moosebar and Gates Formations crop out in the deformed Foothills belt south of Fort St. John, British Columbia. They permit examination of the depositional environments of sandstones and conglomerates that are gas-bearing in the equivalent Wilrich-Falher interval of the Deep basin of Alberta and British Columbia. The Moosebar-Gates interval consists of several upward-coarsening and marine to nonmarine sequences. Moosebar bioturbated shales pass upward into turbidites and offshore storm deposits. Flow directions indicate a north-dipping paleoslope. A second coarsening-upward sequence at the top of the Moosebar and base of the Gates terminates in a lenticular fluvial conglomerate up to 30 m thick, which is overlain by coals, carbonaceous mudstones, and sandstones. Above the carbonaceous zone, fluvial conglomerates in the south grade into beach conglomerates northward. The upper part of the beach conglomerate consists of exposed three-dimensional storm berms, at least 500 m long, up to 1.5 m high, with wavelengths of 12 to 24 m. The berms trend east-west. Seaward of the conglomerate beach are herringbone cross-bedded (tidal) sandstones with a marine trace fauna. Graded sharp-based conglomerates also are present. Farther north, at the same stratigraphic level, is a series of partly overlapping conglomerate bars up to 5 m thick and 40 to 50 m across. The tops of these bars are covered with storm-formed symmetric conglomeratic dunes. Data suggest that four major environments (fluvial, beach, offshore conglomerate bars, and offshore graded storm conglomerates) should be identifiable and predictable in the subsurface. (JMT)

Leckie, D.A., Walker, R.G.

1982-02-01

8

HfO2/GeOxNy/Ge gate stacks with sub-nanometer capacitance equivalent thickness and low interface trap density by in situ NH3 plasma pretreatment  

NASA Astrophysics Data System (ADS)

The native oxides on Ge substrates can be transformed into GeOxNy by in situ NH3 plasma pretreatment. The interfacial and electrical properties of HfO2 caps gate stacks on Ge with and without ultrathin GeOxNy barrier layers have been investigated thoroughly. HfO2/GeOxNy/Ge stacking structure shows a sharp and flat interface between HfO2 and Ge substrates without recognized interfacial layer. In situ NH3 plasma pretreatment effectively improves the electrical properties such as higher accumulation capacitance, smaller frequency dispersion, and lower interface trap density (Dit) than without NH3 plasma pretreatment. It is ascribed to that fact that the GeOxNy barrier layer between HfO2 and Ge substrates shows better thermal stability and suppresses the Ge outdiffusion. The 3-nm-thick HfO2 gate stacks on Ge with 60 s NH3 plasma pretreatment exhibit a capacitance equivalent thickness of 0.96 nm and a leakage current density of 1.12 mA/cm2 at +1 V gate bias with acceptable Dit value of 3.42 × 1012 eV-1 cm-2. These results indicate that the surface nitridation by in situ NH3 plasma pretreatment may be a promising approach for the realization of high quality Ge-based transistor devices.

Cao, Yan-Qiang; Chen, Jun; Liu, Xiao-Jie; Li, Xin; Cao, Zheng-Yi; Ma, Yuan-Jie; Wu, Di; Li, Ai-Dong

2015-01-01

9

Equivalent Fractions  

NSDL National Science Digital Library

In this NCTM Android app a user identifies equivalent fractions for a given random fraction or one of the player's own. The user creates their representations by dividing and shading either a square or circular region. The fractions are shown as locations on the number line and their equivalency is demonstrated when they are at the same point. The user has the ability to construct a table of equivalent fractions. This app is related to an Illuminations activity and an iOS app that are cataloged separately.

2012-07-31

10

Equivalent Fractions  

NSDL National Science Digital Library

In this NCTM iOS app a user identifies equivalent fractions for a given random fraction or one of the player's own. The user creates their representations by dividing and shading either a square or circular region. The fractions are shown as locations on the number line and their equivalency is demonstrated when they are at the same point. The user has the ability to construct a table of equivalent fractions. This app is related to an Illuminations activity and an Android app that are cataloged separately.

2012-08-10

11

Equivalent Fractions  

NSDL National Science Digital Library

This interactive Java applet presents an array of common fractions sometimes referred to as a wall. Fractions less than one with denominators from 2 through 16 are placed to scale horizontally. The learner then moves a mouse to highlight equivalent sets of fractions vertically. Links to related topics are included.

2012-01-01

12

Matching Derived Functionally-Same Stimulus Relations: Equivalence-Equivalence and Classical Analogies  

ERIC Educational Resources Information Center

Previous studies have shown that, after being trained on A-B and A-C matching tasks, subjects match not only functionally-same B and C stimuli (stimulus equivalence), but also BC compounds with same-class elements and BC compounds with different-class elements (equivalence-equivalence). Similar performances are required in classical analogies (a :…

Carpentier, Franck; Smeets, Paul M.; Barnes-Holmes, Dermot; Stewart, Ian

2004-01-01

13

Magnetic Trapping - Trapped Radiation  

NSDL National Science Digital Library

This set of five web pages provides a non-mathematical introduction to the motion of charged particles in magnetic fields. These pages describe the "guiding center motion" which determines the motion of ions and electrons trapped in the Earth's magnetic field and in laboratory plasma devices. Also covered are gyration and mirroring, adiabatic invariance and drifts due to an electric field and gradients in the magnetic field intensity. This is part of the work "The Exploration of the Earth's Magnetosphere". A Spanish translation is available.

Stern, David

2005-04-27

14

Trapping Coyotes  

E-print Network

establish regular travel routes along livestock trails, ranch roads, canyons, ridges or any path that offers easy travel and good visibili- ty.Atrappercanfindthesetravelroutesbylook- ing for coyote sign, tracks and droppings. Coyote tracks are similar to dog... trapping non- target animals such as opossums, raccoons, skunks, badgers, etc., under-pan springs can be usedtoincreasetheamountofpressurerequired to throw the trap. The under-pan spring fits on the base of the trap and provides tension...

Texas Wildlife Services

2008-04-15

15

Optical trapping  

SciTech Connect

Since their invention just over 20 years ago, optical traps have emerged as a powerful tool with broad-reaching applications in biology and physics. Capabilities have evolved from simple manipulation to the application of calibrated forces on - and the measurement of nanometer-level displacements of - optically trapped objects. We review progress in the development of optical trapping apparatus, including instrument design considerations, position detection schemes and calibration techniques, with an emphasis on recent advances. We conclude with a brief summary of innovative optical trapping configurations and applications.

Neuman, Keir C.; Block, Steven M. [Department of Biological Sciences, and Department of Applied Physics, Stanford University, Stanford, California 94305 (United States)

2004-09-01

16

Quantum computing with trapped ions  

Microsoft Academic Search

Quantum computers hold the promise of solving certain computational tasks much more efficiently than classical computers. We review recent experimental advances towards a quantum computer with trapped ions. In particular, various implementations of qubits, quantum gates and some key experiments are discussed. Furthermore, we review some implementations of quantum algorithms such as a deterministic teleportation of quantum information and an

H. Häffner; C. F. Roos; R. Blatt

2008-01-01

17

PATHOGEN EQUIVALENCY COMMITTEE UPDATE: PFRP EQUIVALENCY DETERMINATIONS  

EPA Science Inventory

This presentation will: Review the mandate of the Pathogen Equivalency Committee Review the PEC's current membership of 10 Discuss how a typical application is evaluated Note where information can be found List present deliberations/applications and describe t...

18

Equivalence principles and electromagnetism  

NASA Technical Reports Server (NTRS)

The implications of the weak equivalence principles are investigated in detail for electromagnetic systems in a general framework. In particular, it is shown that the universality of free-fall trajectories (Galileo weak equivalence principle) does not imply the validity of the Einstein equivalence principle. However, the Galileo principle plus the universality of free-fall rotation states does imply the Einstein principle.

Ni, W.-T.

1977-01-01

19

Salisbury hospital's steam trap success.  

PubMed

With the Carbon Reduction Commitment now fully in force, and the NHS tasked with achieving tough carbon emission reduction targets in line with both UK and EU mandates, healthcare estates teams across the country are seeking cost-effective ways to reduce energy consumption. Against this backdrop, Salisbury District Hospital has implemented a concerted energy-saving programme, key elements of which include replacing existing bucket steam traps with higher performing, lower maintenance, and more effective GEM venturi steam traps from Thermal Energy International (TEI), installing a new gas CHP engine, and looking into fitting a TEI condensate economiser system. PMID:21485315

Baillie, Jonathan

2011-03-01

20

Ripple Trap  

NASA Technical Reports Server (NTRS)

3 April 2006 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows the margin of a lava flow on a cratered plain in the Athabasca Vallis region of Mars. Remarkably, the cratered plain in this scene is essentially free of bright, windblown ripples. Conversely, the lava flow apparently acted as a trap for windblown materials, illustrated by the presence of the light-toned, wave-like texture over much of the flow. That the lava flow surface trapped windblown sand and granules better than the cratered plain indicates that the flow surface has a rougher texture at a scale too small to resolve in this image.

Location near: 10.7oN, 204.5oW Image width: 3 km (1.9 mi) Illumination from: lower left Season: Northern Winter

2006-01-01

21

Task breakdown  

NASA Technical Reports Server (NTRS)

The topics concerning the Center for Space Construction (CSC) space construction breakdown structure are presented in viewgraph form. It is concluded that four components describe a task -- effecting, information gathering, analysis, and regulation; uncertainties effect the relative amount of information gathering and analysis that occurs; and that task timing requirements drive the 'location in time' of cognition.

Pavlich, Jane

1990-01-01

22

Interaction of trapped ions with trapped atoms  

E-print Network

In this thesis, I present results from two Paul-trap based ion traps carried out in the Vuleti? laboratory: the Atom-Ion trap for collision studies between cold atoms and cold ions, and the Cavity-Array trap for studying ...

Grier, Andrew T. (Andrew Todd)

2011-01-01

23

Enclosed bark as a pollen trap  

USGS Publications Warehouse

Counts were made of pollen in traps formed by enclosed bark in two remnants of bristlecone pine, Pinus aristata Engelm., from the White Mountains of east-central California. The traps, dated by tree-rings at A.D. 350 and 1300 B.C., contained a major complex of pine-sagebrush pollen and traces of other species, representing the equivalent of the present vegetation.

Adam, D.P.; Ferguson, C.W.; Lamarch, V.C., Jr.

1967-01-01

24

Multiple paths in complex tasks  

NASA Technical Reports Server (NTRS)

The relationship between utility judgments of subtask paths and the utility of the task as a whole was examined. The convergent validation procedure is based on the assumption that measurements of the same quantity done with different methods should covary. The utility measures of the subtasks were obtained during the performance of an aircraft flight controller navigation task. Analyses helped decide among various models of subtask utility combination, whether the utility ratings of subtask paths predict the whole tasks utility rating, and indirectly, whether judgmental models need to include the equivalent of cognitive noise.

Galanter, Eugene; Wiegand, Thomas; Mark, Gloria

1987-01-01

25

Power System Dynamic Equivalents  

Microsoft Academic Search

This paper describes a method for determining a simplified equivalent mathematical representation of portions of a power system for transient stability analysis. The method leads to equations that do not correspond directly to a system composed of normal power system components. Conditions under which it is possible to obtain such an equivalent are given, and the results of applying the

Albert Chang; Mahmood Adibi

1970-01-01

26

zTrap: zebrafish gene trap and enhancer trap database  

Microsoft Academic Search

BACKGROUND: We have developed genetic methods in zebrafish by using the Tol2 transposable element; namely, transgenesis, gene trapping, enhancer trapping and the Gal4FF-UAS system. Gene trap constructs contain a splice acceptor and the GFP or Gal4FF (a modified version of the yeast Gal4 transcription activator) gene, and enhancer trap constructs contain the zebrafish hsp70l promoter and the GFP or Gal4FF

Koichi Kawakami; Gembu Abe; Tokuko Asada; Kazuhide Asakawa; Ryuichi Fukuda; Aki Ito; Pradeep Lal; Naoko Mouri; Akira Muto; Maximilliano L Suster; Hitomi Takakubo; Akihiro Urasaki; Hironori Wada; Mikio Yoshida

2010-01-01

27

Nonequivalence of equivalence principles  

E-print Network

Equivalence principles played a central role in the development of general relativity. Furthermore, they have provided operative procedures for testing the validity of general relativity, or constraining competing theories of gravitation. This has led to a flourishing of different, and inequivalent, formulations of these principles, with the undesired consequence that often the same name, "equivalence principle", is associated with statements having a quite different physical meaning. In this paper we provide a precise formulation of the several incarnations of the equivalence principle, clarifying their uses and reciprocal relations. We also discuss their possible role as selecting principles in the design and classification of viable theories of gravitation.

Eolo Di Casola; Stefano Liberati; Sebastiano Sonego

2013-10-28

28

Nonequivalence of equivalence principles  

NASA Astrophysics Data System (ADS)

Equivalence principles played a central role in the development of general relativity. Furthermore, they have provided operative procedures for testing the validity of general relativity, or constraining competing theories of gravitation. This has led to a flourishing of different, and inequivalent, formulations of these principles, with the undesired consequence that often the same name, "equivalence principle," is associated with statements having a quite different physical meaning. In this paper, we provide a precise formulation of the several incarnations of the equivalence principle, clarifying their uses and reciprocal relations. We also discuss their possible role as selecting principles in the design and classification of viable theories of gravitation.

Di Casola, Eolo; Liberati, Stefano; Sonego, Sebastiano

2015-01-01

29

Neutron dose equivalent meter  

DOEpatents

A neutron dose equivalent detector for measuring neutron dose capable of accurately responding to neutron energies according to published fluence to dose curves. The neutron dose equivalent meter has an inner sphere of polyethylene, with a middle shell overlying the inner sphere, the middle shell comprising RTV.RTM. silicone (organosiloxane) loaded with boron. An outer shell overlies the middle shell and comprises polyethylene loaded with tungsten. The neutron dose equivalent meter defines a channel through the outer shell, the middle shell, and the inner sphere for accepting a neutron counter tube. The outer shell is loaded with tungsten to provide neutron generation, increasing the neutron dose equivalent meter's response sensitivity above 8 MeV.

Olsher, Richard H. (Los Alamos, NM); Hsu, Hsiao-Hua (Los Alamos, NM); Casson, William H. (Los Alamos, NM); Vasilik, Dennis G. (Los Alamos, NM); Kleck, Jeffrey H. (Menlo Park, CA); Beverding, Anthony (Foster City, CA)

1996-01-01

30

Migraine equivalents in childhood.  

PubMed

Migraine equivalents are a group of periodic and paroxysmal neurologic diseases. Because headache is not a prominent symptom, the diagnosis might be challenging. The objective of the study was to evaluate the frequency and outcome of migraine equivalents. This was a retrospective study. We included benign paroxysmal torticollis of infancy, benign paroxysmal vertigo of infancy, abdominal migraine, cyclic vomiting, aura without migraine, and confusional migraine. We evaluated the frequency of events, treatment, and outcome. Out of 674 children with headache, 38 (5.6%) presented with migraine equivalents. Twenty-one were boys and the mean age was 6.1 years. Fifteen had abdominal migraine, 12 benign paroxysmal vertigo, 5 confusional migraine, 3 aura without migraine, 2 paroxysmal torticollis, and 1 cyclic vomiting. Prophylactic treatment was introduced in 23 patients; 4 lost follow-up and 19 had significant improvement. We conclude that the correct diagnosis of migraine equivalents enables an effective treatment with an excellent outcome. PMID:24092892

Teixeira, Karine C S; Montenegro, Maria Augusta; Guerreiro, Marilisa M

2014-10-01

31

Trapping ions in a segmented ring trap  

NASA Astrophysics Data System (ADS)

We demonstrate robust trapping in an ion trap which has a ring shaped RF node. Ions are back-side loaded through a small 10 ?m diameter loading hole and we have demonstrated thousands of complete circuits around the trap. Each circuit passes through 44 trapping zones; the trap has 89 independent DC control electrodes. Measurements of the tangential secular frequency indicate a weak dependence on the RF and the loading hole. The ion trap is fabricated using four metal layers, allowing for the inner islanded electrodes to be electrically routed underneath the trap with negligible effects on the trapped ions. [4pt] This work was supported by the Intelligence Advanced Research Projects Activity (IARPA). Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the US Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.

Tabakov, B. P.; Sterk, J. D.; Benito, F.; Haltli, R.; Tigges, C. P.; Stick, D.; Blain, M. G.; Moehring, D. L.

2012-06-01

32

Learning Tasks  

ERIC Educational Resources Information Center

Government budget constraints had forced the Emergency Dispatch Center (EDC) at a military installation to work with less than the normal number of staff. A Program Proposal was developed previously that had determined that a learning gap existed in the researcher's work environment at a military installation. To counter this gap, Learning Tasks…

Baskas, Richard S.

2012-01-01

33

Representations of Decision-Theoretic Planning Tasks  

Microsoft Academic Search

Goal-directed Markov Decision Process models (GDMDPs) are good models for many decision-theoretic planning tasks. They have been used in conjunction with two different re- ward structures, namely the goal-reward representation and the action-penalty representation. We apply GDMDPs to planning tasks in the presence of traps such as steep slopes for outdoor robots or staircases for indoor robots, and study the

Sven Koenig; Yaxin Liu

2000-01-01

34

Five Equivalent d Orbitals  

ERIC Educational Resources Information Center

Amplifies and clarifies a previous paper on pyramidal d orbitals. Discusses two sets of pyramid d orbitals with respect to their maximum bond strength and their symmetry. Authors described the oblate and prolate pentagonal antiprisms arising from the two sets of five equivalent d orbitals. (RR)

Pauling, Linus; McClure, Vance

1970-01-01

35

The Interaction Equivalency Theorem  

ERIC Educational Resources Information Center

This paper examines the key issues regarding The Interaction Equivalency Theorem posited by Anderson (2003a), which consists of the three interaction elements found in formal education courses among teacher, student, and content. It first examines the core concepts of the theorem and argues that two theses of different dimensions can be…

Miyazoe, Terumi; Anderson, Terry

2010-01-01

36

Everyday Mathematics Equivalent Fractions  

NSDL National Science Digital Library

This iOS app ($) provides students with practice and reinforcement of fraction concepts in a solitaire context. Users try to clear a board by matching cards displaying equivalent visual and numeric representations of fractions, while getting feedback and scoring points for accuracy. A tutorial with voice explains how to play.

2011-02-03

37

Biomonitoring equivalents for hexachlorobenzene  

Microsoft Academic Search

Recent efforts worldwide have resulted in a growing database of measured concentrations of chemicals in blood and urine samples taken from the general population. However, few tools exist to assist in the interpretation of the measured values in a health risk context. Biomonitoring equivalents (BEs) are defined as the concentration or range of concentrations of a chemical or its metabolite

Lesa L. Aylward; Sean M. Hays; Michelle Gagné; Andy Nong; Kannan Krishnan

2010-01-01

38

Biomonitoring Equivalents for triclosan  

Microsoft Academic Search

Recent efforts worldwide have resulted in a growing database of measured concentrations of chemicals in blood and urine samples taken from the general population. However, few tools exist to assist in the interpretation of the measured values in a health risk context. Biomonitoring Equivalents (BEs) are defined as the concentration or range of concentrations of a chemical or its metabolite(s)

Kannan Krishnan; Michelle Gagné; Andy Nong; Lesa L. Aylward; Sean M. Hays

2010-01-01

39

PATHOGEN EQUIVALENCY COMMITTEE (PEC)  

EPA Science Inventory

The U.S. Environmental Protection Agency created the PEC in 1985 to make recommendations to EPA and State managers on the equivalency of unproven sewage sludge disinfection technologies/processes to either a Process to Significantly Reduce Pathogens (PSRP) or a Process to Further...

40

Equivalent bipolar fuzzy relations  

Microsoft Academic Search

We consider a relation between bipolar fuzzy relations (originally called intuitionistic fuzzy relations). This relation turns out to be an equivalence in the family of all bipolar fuzzy relations in a given (crisp) set. It also has many other properties which seem to be useful in applications. We study standard properties of bipolar fuzzy relations in the context of the

Urszula Dudziak; Barbara Pekala

2010-01-01

41

Microfabricated Ion Traps  

E-print Network

Ion traps offer the opportunity to study fundamental quantum systems with high level of accuracy highly decoupled from the environment. Individual atomic ions can be controlled and manipulated with electric fields, cooled to the ground state of motion with laser cooling and coherently manipulated using optical and microwave radiation. Microfabricated ion traps hold the advantage of allowing for smaller trap dimensions and better scalability towards large ion trap arrays also making them a vital ingredient for next generation quantum technologies. Here we provide an introduction into the principles and operation of microfabricated ion traps. We show an overview of material and electrical considerations which are vital for the design of such trap structures. We provide guidance in how to choose the appropriate fabrication design, consider different methods for the fabrication of microfabricated ion traps and discuss previously realized structures. We also discuss the phenomenon of anomalous heating of ions within ion traps, which becomes an important factor in the miniaturization of ion traps.

Marcus D. Hughes; Bjoern Lekitsch; Jiddu A. Broersma; Winfried K. Hensinger

2011-01-17

42

Plutonium 239 Equivalency Calculations  

SciTech Connect

This document provides the basis for converting actual weapons grade plutonium mass to a plutonium equivalency (PuE) mass of Plutonium 239. The conversion can be accomplished by performing calculations utilizing either: (1) Isotopic conversions factors (CF{sub isotope}), or (2) 30-year-old weapons grade conversion factor (CF{sub 30 yr}) Both of these methods are provided in this document. Material mass and isotopic data are needed to calculate PuE using the isotopic conversion factors, which will provide the actual PuE value at the time of calculation. PuE is the summation of the isotopic masses times their associated isotopic conversion factors for plutonium 239. Isotopic conversion factors are calculated by a normalized equation, relative to Plutonium 239, of specific activity (SA) and cumulated dose inhalation affects based on 50-yr committed effective dose equivalent (CEDE). The isotopic conversion factors for converting weapons grade plutonium to PuE are provided in Table-1. The unit for specific activity (SA) is curies per gram (Ci/g) and the isotopic SA values come from reference [1]. The cumulated dose inhalation effect values in units of rem/Ci are based on 50-yr committed effective dose equivalent (CEDE). A person irradiated by gamma radiation outside the body will receive a dose only during the period of irradiation. However, following an intake by inhalation, some radionuclides persist in the body and irradiate the various tissues for many years. There are three groups CEDE data representing lengths of time of 0.5 (D), 50 (W) and 500 (Y) days, which are in reference [2]. The CEDE values in the (W) group demonstrates the highest dose equivalent value; therefore they are used for the calculation.

Wen, J

2011-05-31

43

Visuospatial Tasks Affect Locomotor Control More than Nonspatial Tasks in Older People  

PubMed Central

Background Previous research has shown that visuospatial processing requiring working memory is particularly important for balance control during standing and stepping, and that limited spatial encoding contributes to increased interference in postural control dual tasks. However, visuospatial involvement during locomotion has not been directly determined. This study examined the effects of a visuospatial cognitive task versus a nonspatial cognitive task on gait speed, smoothness and variability in older people, while controlling for task difficulty. Methods Thirty-six people aged ?75 years performed three walking trials along a 20 m walkway under the following conditions: (i) an easy nonspatial task; (ii) a difficult nonspatial task; (iii) an easy visuospatial task; and (iv) a difficult visuospatial task. Gait parameters were computed from a tri-axial accelerometer attached to the sacrum. The cognitive task response times and percentage of correct answers during walking and seated trials were also computed. Results No significant differences in either cognitive task type error rates or response times were evident in the seated conditions, indicating equivalent task difficulty. In the walking trials, participants responded faster to the visuospatial tasks than the nonspatial tasks but at the cost of making significantly more cognitive task errors. Participants also walked slower, took shorter steps, had greater step time variability and less smooth pelvis accelerations when concurrently performing the visuospatial tasks compared with the nonspatial tasks and when performing the difficult compared with the easy cognitive tasks. Conclusions Compared with nonspatial cognitive tasks, visuospatial cognitive tasks led to a slower, more variable and less smooth gait pattern. These findings suggest that visuospatial processing might share common networks with locomotor control, further supporting the hypothesis that gait changes during dual task paradigms are not simply due to limited attentional resources but to competition for common networks for spatial information encoding. PMID:25285913

Menant, Jasmine C.; Sturnieks, Daina L.; Brodie, Matthew A. D.; Smith, Stuart T.; Lord, Stephen R.

2014-01-01

44

Superconducting microfabricated ion traps  

E-print Network

We fabricate superconducting ion traps with niobium and niobium nitride and trap single [superscript 88]Sr ions at cryogenic temperatures. The superconducting transition is verified and characterized by measuring the ...

Wang, Shannon Xuanyue

45

Acute alcohol effects on repetition priming and word recognition memory with equivalent memory cues  

Microsoft Academic Search

Acute alcohol intoxication effects on memory were examined using a recollection-based word recognition memory task and a repetition priming task of memory for the same information without explicit reference to the study context. Memory cues were equivalent across tasks; encoding was manipulated by varying the frequency of occurrence (FOC) of words in the study lists. Twenty-two female and male social

Suchismita Ray; Marsha E. Bates

2006-01-01

46

Acute Alcohol Effects on Repetition Priming and Word Recognition Memory with Equivalent Memory Cues  

ERIC Educational Resources Information Center

Acute alcohol intoxication effects on memory were examined using a recollection-based word recognition memory task and a repetition priming task of memory for the same information without explicit reference to the study context. Memory cues were equivalent across tasks; encoding was manipulated by varying the frequency of occurrence (FOC) of words…

Ray, Suchismita; Bates, Marsha E.

2006-01-01

47

A Better Fly Trap  

NSDL National Science Digital Library

In this activity, learners observe fly behavior and then build a flytrap. They make more observations, compare the effectiveness of different traps, and modify their traps to increase their effectiveness. In doing so, learners consider what variables make for an effective trap as well as learning how to study the behavior of an animal. Even pesky flies provide an interesting challenge.

2013-02-25

48

Trap centers in molybdates  

NASA Astrophysics Data System (ADS)

Charge carrier trapping centers have been studied in molybdates CaMoO4, SrMoO4 and PbMoO4 with the scheelite crystal structure as well as in ZnMoO4, which crystallize in a-ZnMoO4 structural type. The trap parameters such as activation energies and frequency factors have been determined. It is shown for the first time that both electrons and holes are trapped by the elements of regular crystal structure in ZnMoO4. The effect of the charge carrier trapping on luminescence properties is demonstrated. Potential influence of the traps on the scintillation process is discussed.

Spassky, D. A.; Nagirnyi, V.; Mikhailin, V. V.; Savon, A. E.; Belsky, A. N.; Laguta, V. V.; Buryi, M.; Galashov, E. N.; Shlegel, V. N.; Voronina, I. S.; Zadneprovski, B. I.

2013-10-01

49

Trap style influences wild pig behavior and trapping success  

USGS Publications Warehouse

Despite the efforts of many natural resource professionals, wild pig (Sus scrofa) populations are expanding in many areas of the world. Although many creative techniques for controlling pig populations are being explored, trapping has been and still is themost commonly usedmethod of population control formany public and private land managers. We conducted an observational study to examine the efficiency of 2 frequently used trap styles: a small, portable box-style trap and a larger, semi-permanent, corral-style trap.We used game cameras to examine patterns of trap entry by wild pigs around each style of trap, and we conducted a trapping session to compare trapping success between trap styles. Adult female and juvenile wild pigs entered both styles of trap more readily than did adult males, and adult males seemed particularly averse to entering box traps. Less than 10% of adult male visits to box traps resulted in entries, easily the least percentage of any class at any style of trap. Adult females entered corral traps approximately 2.2 times more often per visit than box traps and re-entered corral traps >2 times more frequently. Juveniles entered and reentered both box and corral traps at similar rates. Overall (all-class) entry-per-visit rates at corral traps (0.71) were nearly double that of box traps (0.37). Subsequent trapping data supported these preliminary entry data; the capture rate for corral traps was >4 times that of box traps. Our data suggest that corral traps are temporally and economically superior to box traps with respect to efficiency; that is, corral traps effectively trap more pigs per trap night at a lower cost per pig than do box traps. ?? 2011 The Wildlife Society.

Williams, B.L.; Holtfreter, R.W.; Ditchkoff, S.S.; Grand, J.B.

2011-01-01

50

Grade Level Expectations and Grade Equivalent Scores in Reading Tests.  

ERIC Educational Resources Information Center

Statistical methods and test writing for reading comprehension have been based on the assumption that certain reading tasks or levels are appropriate at one age level that would be too difficult at another. A clear-cut determination of grade levels for reading materials has, however, not been defined. Grade and age equivalent scores on silent…

Tucker, Elizabeth Sulzby

51

Neutral atom traps.  

SciTech Connect

This report describes progress in designing a neutral atom trap capable of trapping sub millikelvin atom in a magnetic trap and shuttling the atoms across the atom chip from a collection area to an optical cavity. The numerical simulation and atom chip design are discussed. Also, discussed are preliminary calculations of quantum noise sources in Kerr nonlinear optics measurements based on electromagnetically induced transparency. These types of measurements may be important for quantum nondemolition measurements at the few photon limit.

Pack, Michael Vern

2008-12-01

52

Exploring Mouse Trap History  

Microsoft Academic Search

Since intelligent design (ID) advocates claimed the ubiquitous mouse trap as an example of systems that cannot have evolved,\\u000a mouse trap history is doubly relevant to studying material culture. On the one hand, debunking ID claims about mouse traps\\u000a and, by implication, also about other irreducibly complex systems has a high educational value. On the other hand, a case study

Joachim L. Dagg

53

Motor equivalence during multi-finger accurate force production.  

PubMed

We explored stability of multi-finger cyclical accurate force production action by analysis of responses to small perturbations applied to one of the fingers and inter-cycle analysis of variance. Healthy subjects performed two versions of the cyclical task, with and without an explicit target. The "inverse piano" apparatus was used to lift/lower a finger by 1 cm over 0.5 s; the subjects were always instructed to perform the task as accurate as they could at all times. Deviations in the spaces of finger forces and modes (hypothetical commands to individual fingers) were quantified in directions that did not change total force (motor equivalent) and in directions that changed the total force (non-motor equivalent). Motor equivalent deviations started immediately with the perturbation and increased progressively with time. After a sequence of lifting-lowering perturbations leading to the initial conditions, motor equivalent deviations were dominating. These phenomena were less pronounced for analysis performed with respect to the total moment of force with respect to an axis parallel to the forearm/hand. Analysis of inter-cycle variance showed consistently higher variance in a subspace that did not change the total force as compared to the variance that affected total force. We interpret the results as reflections of task-specific stability of the redundant multi-finger system. Large motor equivalent deviations suggest that reactions of the neuromotor system to a perturbation involve large changes in neural commands that do not affect salient performance variables, even during actions with the purpose to correct those salient variables. Consistency of the analyses of motor equivalence and variance analysis provides additional support for the idea of task-specific stability ensured at a neural level. PMID:25344311

Mattos, Daniela; Schöner, Gregor; Zatsiorsky, Vladimir M; Latash, Mark L

2015-02-01

54

Equivalence principle and gravitational redshift.  

PubMed

We investigate leading order deviations from general relativity that violate the Einstein equivalence principle in the gravitational standard model extension. We show that redshift experiments based on matter waves and clock comparisons are equivalent to one another. Consideration of torsion balance tests, along with matter-wave, microwave, optical, and Mössbauer clock tests, yields comprehensive limits on spin-independent Einstein equivalence principle-violating standard model extension terms at the 10(-6) level. PMID:21568541

Hohensee, Michael A; Chu, Steven; Peters, Achim; Müller, Holger

2011-04-15

55

Equivalence Principle and Gravitational Redshift  

SciTech Connect

We investigate leading order deviations from general relativity that violate the Einstein equivalence principle in the gravitational standard model extension. We show that redshift experiments based on matter waves and clock comparisons are equivalent to one another. Consideration of torsion balance tests, along with matter-wave, microwave, optical, and Moessbauer clock tests, yields comprehensive limits on spin-independent Einstein equivalence principle-violating standard model extension terms at the 10{sup -6} level.

Hohensee, Michael A.; Chu, Steven; Mueller, Holger [Department of Physics, University of California, Berkeley, California 94720 (United States); Peters, Achim [Institut fuer Physik, Humboldt-Universitaet zu Berlin, Newtonstrasse 15, 12489 Berlin (Germany)

2011-04-15

56

Steam Trap Management  

E-print Network

A medium-sized plant of a high technology company is reaping the benefits of a Pro-active Steam Trap Program provided by Yarway's TECH/SERV Division. Initial work began March '84 and the most recent steam trap feasibility study conducted in March...

Murphy, J. J.; Hirtner, H. H.

57

Diesel particulate traps  

Microsoft Academic Search

For use with a diesel engine having at least one exhaust bank, a particulate trap system is described comprising: an exhaust conduit ducting exhaust materials firstly through an exhaust cooler, thence to a diesel particulate trap, thence to the atmosphere, a by-pass conduit connected in parallel with the exhaust cooler between a first location upstream of the cooler and a

Burlington

1987-01-01

58

Optical Trapping of Nanoparticles  

PubMed Central

Optical trapping is a technique for immobilizing and manipulating small objects in a gentle way using light, and it has been widely applied in trapping and manipulating small biological particles. Ashkin and co-workers first demonstrated optical tweezers using a single focused beam1. The single beam trap can be described accurately using the perturbative gradient force formulation in the case of small Rayleigh regime particles1. In the perturbative regime, the optical power required for trapping a particle scales as the inverse fourth power of the particle size. High optical powers can damage dielectric particles and cause heating. For instance, trapped latex spheres of 109 nm in diameter were destroyed by a 15 mW beam in 25 sec1, which has serious implications for biological matter2,3. A self-induced back-action (SIBA) optical trapping was proposed to trap 50 nm polystyrene spheres in the non-perturbative regime4. In a non-perturbative regime, even a small particle with little permittivity contrast to the background can influence significantly the ambient electromagnetic field and induce a large optical force. As a particle enters an illuminated aperture, light transmission increases dramatically because of dielectric loading. If the particle attempts to leave the aperture, decreased transmission causes a change in momentum outwards from the hole and, by Newton's Third Law, results in a force on the particle inwards into the hole, trapping the particle. The light transmission can be monitored; hence, the trap can become a sensor. The SIBA trapping technique can be further improved by using a double-nanohole structure. The double-nanohole structure has been shown to give a strong local field enhancement5,6. Between the two sharp tips of the double-nanohole, a small particle can cause a large change in optical transmission, thereby inducing a large optical force. As a result, smaller nanoparticles can be trapped, such as 12 nm silicate spheres7 and 3.4 nm hydrodynamic radius bovine serum albumin proteins8. In this work, the experimental configuration used for nanoparticle trapping is outlined. First, we detail the assembly of the trapping setup which is based on a Thorlabs Optical Tweezer Kit. Next, we explain the nanofabrication procedure of the double-nanohole in a metal film, the fabrication of the microfluidic chamber and the sample preparation. Finally, we detail the data acquisition procedure and provide typical results for trapping 20 nm polystyrene nanospheres. PMID:23354173

Bergeron, Jarrah; Zehtabi-Oskuie, Ana; Ghaffari, Saeedeh; Pang, Yuanjie; Gordon, Reuven

2013-01-01

59

Optically programmable excitonic traps.  

PubMed

With atomic systems, optically programmed trapping potentials have led to remarkable progress in quantum optics and quantum information science. Programmable trapping potentials could have a similar impact on studies of semiconductor quasi-particles, particularly excitons. However, engineering such potentials inside a semiconductor heterostructure remains an outstanding challenge and optical techniques have not yet achieved a high degree of control. Here, we synthesize optically programmable trapping potentials for indirect excitons of bilayer heterostructures. Our approach relies on the injection and spatial patterning of charges trapped in a field-effect device. We thereby imprint in-situ and on-demand electrostatic traps into which we optically inject cold and dense ensembles of excitons. This technique creates new opportunities to improve state-of-the-art technologies for the study of collective quantum behavior of excitons and also for the functionalisation of emerging exciton-based opto-electronic circuits. PMID:23546532

Alloing, Mathieu; Lemaître, Aristide; Galopin, Elisabeth; Dubin, François

2013-01-01

60

Nonlinear integrable ion traps  

SciTech Connect

Quadrupole ion traps can be transformed into nonlinear traps with integrable motion by adding special electrostatic potentials. This can be done with both stationary potentials (electrostatic plus a uniform magnetic field) and with time-dependent electric potentials. These potentials are chosen such that the single particle Hamilton-Jacobi equations of motion are separable in some coordinate systems. The electrostatic potentials have several free adjustable parameters allowing for a quadrupole trap to be transformed into, for example, a double-well or a toroidal-well system. The particle motion remains regular, non-chaotic, integrable in quadratures, and stable for a wide range of parameters. We present two examples of how to realize such a system in case of a time-independent (the Penning trap) as well as a time-dependent (the Paul trap) configuration.

Nagaitsev, S.; /Fermilab; Danilov, V.; /SNS Project, Oak Ridge

2011-10-01

61

Surface trap for ytterbium ions  

E-print Network

We conducted an experiment to load a shallow planar ion trap from a cold atom source of Ytterbium using photoionization. The surface trap consisted of a three-rod radio frequency Paul trap fabricated using standard printed ...

Campbell, Jonathan A. (Jonathan Alan)

2006-01-01

62

Aesthetic law and ‘equivalent effect’  

Microsoft Academic Search

Since no translation of Chinese classics has really achieved an ‘equivalent effect’ as proposed by some translation theorists, this article explores the limitations of the ‘equivalent effect’ theory. This is done by means of a dynamic analysis of the generation of artistic charm, i.e. the interaction of the text's aesthetic elements with the reader's active reproduction and appreciation of them

Cheng Mei

1996-01-01

63

Equivalence of degenerate Hopf bifurcations  

Microsoft Academic Search

The author proves the equivalence of degenerate Hopf bifurcations which have all their closed orbits at the bifurcation point. Although these Hopf bifurcations have infinity codimension, they can nevertheless occur generically in dynamical systems under constraint such as in the Hamiltonian systems or in the replicator equations; and so in these contexts a treatment of their equivalence is required. The

A. Edalat

1991-01-01

64

The nature of the TRAP-Anti-TRAP complex.  

PubMed

Tryptophan biosynthesis is subject to exquisite control in species of Bacillus and has become one of the best-studied model systems in gene regulation. The protein TRAP (trp RNA-binding attenuation protein) predominantly forms a ring-shaped 11-mer, which binds cognate RNA in the presence of tryptophan to suppress expression of the trp operon. TRAP is itself regulated by the protein Anti-TRAP, which binds to TRAP and prevents RNA binding. To date, the nature of this interaction has proved elusive. Here, we describe mass spectrometry and analytical centrifugation studies of the complex, and 2 crystal structures of the TRAP-Anti-TRAP complex. These crystal structures, both refined to 3.2-A resolution, show that Anti-TRAP binds to TRAP as a trimer, sterically blocking RNA binding. Mass spectrometry shows that 11-mer TRAP may bind up to 5 AT trimers, and an artificial 12-mer TRAP may bind 6. Both forms of TRAP make the same interactions with Anti-TRAP. Crystallization of wild-type TRAP with Anti-TRAP selectively pulls the 12-mer TRAP form out of solution, so the crystal structure of wild-type TRAP-Anti-TRAP complex reflects a minor species from a mixed population. PMID:19164760

Watanabe, Masahiro; Heddle, Jonathan G; Kikuchi, Kenichi; Unzai, Satoru; Akashi, Satoko; Park, Sam-Yong; Tame, Jeremy R H

2009-02-17

65

Preliminary Findings on the Effects of Self-Referring and Evaluative Stimuli on Stimulus Equivalence Class Formation  

ERIC Educational Resources Information Center

Thirty-two subjects completed 2 stimulus equivalence tasks using a matching-to-sample paradigm. One task involved direct reinforcement of conditional discriminations designed to produce derived relations between self-referring stimuli (e.g., me, myself, I) and positive evaluation words (e.g., whole, desirable, perfect). The other task was designed…

Merwin, Rhonda M.; Wilson, Kelly G.

2005-01-01

66

Recalling academic tasks  

NASA Astrophysics Data System (ADS)

This study was focused on what students remembered about five middle school science tasks when they were juniors and seniors in high school. Descriptions of the five tasks were reconstructed from available artifacts and teachers' records, notes and recollections. Three of the five tasks were "authentic" in the sense that students were asked to duplicate the decisions practitioners make in the adult world. The other two tasks were more typical school tasks involving note taking and preparation for a quiz. All five tasks, however, involved use of computers. Students were interviewed to examine what and how well they recalled the tasks and what forms or patterns of recall existed. Analysis of their responses indicated that different kinds of tasks produced different levels of recall. Authentically situated tasks were remembered much better than routine school tasks. Further, authentic tasks centered on design elements were recalled better than those for which design was not as pivotal. Patterns of recall indicated that participants most often recalled the decisions they made, the scenarios of the authentically situated tasks, the consequences of their tasks and the social contexts of the classroom. Task events, in other words, appeared to form a framework upon which students constructed stories of the tasks. The more salient the events, the richer the story, the deeper and more detailed the recall of the task. Thus, authentic tasks appeared to lend themselves to creating stories better than regular school tasks and therefore such tasks were recalled better. Implications of these patterns of recall are discussed with respect to issues of school learning and assessment.

Draper, Franklin Gno

67

Morita equivalence of noncommutative supertori  

SciTech Connect

In this paper we study the extension of Morita equivalence of noncommutative tori to the supersymmetric case. The structure of the symmetry group yielding Morita equivalence appears to be intact but its parameter field becomes supersymmetrized having both body and soul parts. Our result is mainly in the two dimensional case in which noncommutative supertori have been constructed recently: The group SO(2,2,V{sub Z}{sup 0}), where V{sub Z}{sup 0} denotes Grassmann even number whose body part belongs to Z, yields Morita equivalent noncommutative supertori in two dimensions.

Chang-Young, Ee [Department of Physics, Sejong University, Seoul 143-747 (Korea, Republic of); Kim, Hoil [Department of Mathematics, Kyungpook National University, Taegu 702-701 (Korea, Republic of); Nakajima, Hiroaki [Department of Physics and Institute of Basic Science, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of)

2010-06-15

68

Morita equivalence of noncommutative supertori  

NASA Astrophysics Data System (ADS)

In this paper we study the extension of Morita equivalence of noncommutative tori to the supersymmetric case. The structure of the symmetry group yielding Morita equivalence appears to be intact but its parameter field becomes supersymmetrized having both body and soul parts. Our result is mainly in the two dimensional case in which noncommutative supertori have been constructed recently: The group SO(2,2,VZ0), where VZ0 denotes Grassmann even number whose body part belongs to Z, yields Morita equivalent noncommutative supertori in two dimensions.

Chang-Young, Ee; Kim, Hoil; Nakajima, Hiroaki

2010-06-01

69

Unitary equivalence of quantum walks  

NASA Astrophysics Data System (ADS)

A simple coined quantum walk in one dimension can be characterized by a SU (2) operator with three parameters which represents the coin toss. However, different such coin toss operators lead to equivalent dynamics of the quantum walker. In this manuscript we present the unitary equivalence classes of quantum walks and show that all the nonequivalent quantum walks can be distinguished by a single parameter. Moreover, we argue that the electric quantum walks are equivalent to quantum walks with time dependent coin toss operator.

Goyal, Sandeep K.; Konrad, Thomas; Diósi, Lajos

2015-01-01

70

Venus fly trap  

NSDL National Science Digital Library

Time-lapse photos or video show progressions from the start of an event to the end of the event. These time-lapse photos illustrate the growth of a single Venus fly trap. Biological processes require time.

Paul Lenz (None;)

2006-01-26

71

Structural traps 5  

SciTech Connect

This book contains studies of oil and gas fields that are mainly structural in nature. Stratigraphy controls the extend of the reservoir in the traps of several fields, but overall, the main trapping features within the group of fields in this volume are structural. Fields covered in this volume include: Endicott Field, Point Arguello Field, West Puerto Chiquito Field, Dukhan Field, Sendji Field, Ruston Field, Raudhatain Field, Hassi Messaoud Field, Snapper Field, Tirrawarra Field, and Sacha Field.

Foster, N.H.; Beaumont, E.A.

1991-01-01

72

Optical Metrics and Projective Equivalence  

E-print Network

Trajectories of light rays in a static spacetime are described by unparametrised geodesics of the Riemannian optical metric associated with the Lorentzian spacetime metric. We investigate the uniqueness of this structure and demonstrate that two different observers, moving relative to one another, who both see the universe as static may determine the geometry of the light rays differently. More specifically, we classify Lorentzian metrics admitting more than one hyper--surface orthogonal time--like Killing vector and analyze the projective equivalence of the resulting optical metrics. These metrics are shown to be projectively equivalent up to diffeomorphism if the static Killing vectors generate a group $SL(2, \\R)$, but not projectively equivalent in general. We also consider the cosmological $C$--metrics in Einstein--Maxwell theory and demonstrate that optical metrics corresponding to different values of the cosmological constant are projectively equivalent.

Stephen Casey; Maciej Dunajski; Gary Gibbons; Claude Warnick

2011-01-23

73

Optical metrics and projective equivalence  

SciTech Connect

Trajectories of light rays in a static spacetime are described by unparametrized geodesics of the Riemannian optical metric associated with the Lorentzian spacetime metric. We investigate the uniqueness of this structure and demonstrate that two different observers, moving relative to one another, who both see the Universe as static may determine the geometry of the light rays differently. More specifically, we classify Lorentzian metrics admitting more than one hyper-surface orthogonal timelike Killing vector and analyze the projective equivalence of the resulting optical metrics. These metrics are shown to be projectively equivalent up to diffeomorphism if the static Killing vectors generate a group SL(2,R), but not projectively equivalent in general. We also consider the cosmological C metrics in Einstein-Maxwell theory and demonstrate that optical metrics corresponding to different values of the cosmological constant are projectively equivalent.

Casey, Stephen; Dunajski, Maciej; Gibbons, Gary; Warnick, Claude [Department of Applied Mathematics and Theoretical Physics, University of Cambridge, Wilberforce Road, Cambridge CB3 0WA (United Kingdom)

2011-04-15

74

Equivalency Theory and Distance Education.  

ERIC Educational Resources Information Center

Discusses distance education and the need for an accepted theory. Highlights include theories of independent study; theory of industrialization of teaching; theory of interaction and communication; and equivalency theory that is based on local control, personalized instruction, and telecommunications. (LRW)

Simonson, Michael

1999-01-01

75

Diesel particulate traps  

SciTech Connect

For use with a diesel engine having at least one exhaust bank, a particulate trap system is described comprising: an exhaust conduit ducting exhaust materials firstly through an exhaust cooler, thence to a diesel particulate trap, thence to the atmosphere, a by-pass conduit connected in parallel with the exhaust cooler between a first location upstream of the cooler and a second location downstream of the cooler but upstream of the trap, a first valve in the exhaust conduit between the first location and the cooler, a second valve in the by-pass conduit, and microprocessor-based control means which carries out the steps of (a) allowing normal operation with the first valve open and the second valve closed, (b) when backpressure in the exhaust conduit reaches a predetermined level due to particulate build-up in the trap, gradually opening the second valve and closing the first valve, thereby allowing exhaust materials to by-pass the cooler, (c) when the trap begins to regenerate thereby causing increased temperature in the trap, closing the second valve and opening the first valve.

Burlington, K.H.

1987-08-11

76

Quantum Computation with Trapped Ions  

Microsoft Academic Search

Trapped ions can be prepared, manipulated and analyzed with high fidelities. In addition, scalable ion trap architectures have been proposed (Kielpinski et al., Nature 417, 709 (2001).). Therefore trapped ions represent a promising approach to large scale quantum computing. Here we concentrate on the recent advancements of generating entangled states with small ion trap quantum computers. In particular, the creation

H. Häffner; W. Hänsel; C. F. Roos; P. O. Schmidt; M. Riebe; M. Chwalla; D. Chek-Al-Kar; J. Benhelm; U. D. Rapol; T. Körber; C. Becher; O. Gühne; W. Dür; R. Blatt

2008-01-01

77

Barium Ion Trapping Rebecca Schutzengel  

E-print Network

Barium Ion Trapping Rebecca Schutzengel Franklin W. Olin College of Engineering University of Washington INT REU August 20, 2012 Rebecca Schutzengel Barium Ion Trapping August 20, 2012 1 / 12 #12;Uses for Ion Trapping Bell's Inequality tests Quantum Computing Rebecca Schutzengel Barium Ion Trapping August

Washington at Seattle, University of - Department of Physics, Electroweak Interaction Research Group

78

Functional Task Test (FTT)  

NASA Technical Reports Server (NTRS)

This slide presentation reviews the Functional Task Test (FTT), an interdisciplinary testing regimen that has been developed to evaluate astronaut postflight functional performance and related physiological changes. The objectives of the project are: (1) to develop a set of functional tasks that represent critical mission tasks for the Constellation Program, (2) determine the ability to perform these tasks after space flight, (3) Identify the key physiological factors that contribute to functional decrements and (4) Use this information to develop targeted countermeasures.

Bloomberg, Jacob J.; Mulavara, Ajitkumar; Peters, Brian T.; Rescheke, Millard F.; Wood, Scott; Lawrence, Emily; Koffman, Igor; Ploutz-Snyder, Lori; Spiering, Barry A.; Feeback, Daniel L.; Platts, Steven H.; Stenger, Michael B.; Lee, Stuart M.C.; Arzeno, Natalia; Feiveson, Alan H.; Ryder, Jeffrey; Garcia, Yamil; Guilliams, Mark E.

2009-01-01

79

Launching Complex Tasks  

ERIC Educational Resources Information Center

Mathematics lessons can take a variety of formats. In this article, the authors discuss lessons organized around complex mathematical tasks. These lessons usually unfold in three phases. First, the task is introduced to students. Second, students work on solving the task. Third, the teacher "orchestrates" a concluding whole-class discussion in…

Jackson, Kara J.; Shahan, Emily C.; Gibbons, Lynsey K.; Cobb, Paul A.

2012-01-01

80

Digital Library Task Force  

Microsoft Academic Search

In 1995, the IEEE Computer Society established the Task Force on Digital Libraries as a first step leading to a full-fledged Technical Committee. The task force is to promote research in the theory and practice of all aspects of digital libraries. The task force sponsors activities that benefit its members and profession. Such activities include sponsoring and co-sponsoring symposia, sessions

N. R. Adam; R. Holowczak; M. Halem; N. Lal; Y. Yesha

1996-01-01

81

Equivalent damage: A critical assessment  

NASA Technical Reports Server (NTRS)

Concepts in equivalent damage were evaluated to determine their applicability to the life prediction of hot path components of aircraft gas turbine engines. Equivalent damage was defined as being those effects which influence the crack initiation life-time beyond the damage that is measured in uniaxial, fully-reversed sinusoidal and isothermal experiments at low homologous temperatures. Three areas of equivalent damage were examined: mean stress, cumulative damage, and multiaxiality. For each area, a literature survey was conducted to aid in selecting the most appropriate theories. Where possible, data correlations were also used in the evaluation process. A set of criteria was developed for ranking the theories in each equivalent damage regime. These criteria considered aspects of engine utilization as well as the theoretical basis and correlative ability of each theory. In addition, consideration was given to the complex nature of the loading cycle at fatigue critical locations of hot path components; this loading includes non-proportional multiaxial stressing, combined temperature and strain fluctuations, and general creep-fatigue interactions. Through applications of selected equivalent damage theories to some suitable data sets it was found that there is insufficient data to allow specific recommendations of preferred theories for general applications. A series of experiments and areas of further investigations were identified.

Laflen, J. R.; Cook, T. S.

1982-01-01

82

Grid Task Execution  

NASA Technical Reports Server (NTRS)

IPG Execution Service is a framework that reliably executes complex jobs on a computational grid, and is part of the IPG service architecture designed to support location-independent computing. The new grid service enables users to describe the platform on which they need a job to run, which allows the service to locate the desired platform, configure it for the required application, and execute the job. After a job is submitted, users can monitor it through periodic notifications, or through queries. Each job consists of a set of tasks that performs actions such as executing applications and managing data. Each task is executed based on a starting condition that is an expression of the states of other tasks. This formulation allows tasks to be executed in parallel, and also allows a user to specify tasks to execute when other tasks succeed, fail, or are canceled. The two core components of the Execution Service are the Task Database, which stores tasks that have been submitted for execution, and the Task Manager, which executes tasks in the proper order, based on the user-specified starting conditions, and avoids overloading local and remote resources while executing tasks.

Hu, Chaumin

2007-01-01

83

The Reusable Astronomy Portal (TRAP)  

NASA Astrophysics Data System (ADS)

The Reusable Astronomy Portal (TRAP) aims to provide a common platform for rapidly deploying Astronomy Archives to the web. TRAP is currently under development for both the VAO Data Discovery Portal and the MAST Multi-Mission Portal (Figure 1). TRAP consists of 2 major software packages: the TRAP Client and the TRAP Server. The TRAP framework allows developers to deploy the Server, connect to data resources, then focus on building custom tools for the Client. TRAP is built upon proven industry technologies including the Ext/JS JavaScript Component Library, Mono.NET Web Services, and JSON message based APIs. The multi-layered architecture of TRAP decouples each layer: Client, Service and Data Access, enabling each to evolve independently over time. Although currently deployed to provide astronomy science data access, the TRAP architecture is flexible enough to thrive in any distributed data environment.

Donaldson, T.; Rogers, A.; Wallace, G.

2012-09-01

84

Equivalence principle for scalar forces.  

PubMed

The equivalence of inertial and gravitational masses is a defining feature of general relativity. Here, we clarify the status of the equivalence principle for interactions mediated by a universally coupled scalar, motivated partly by recent attempts to modify gravity at cosmological distances. Although a universal scalar-matter coupling is not mandatory, once postulated, it is stable against classical and quantum renormalizations in the matter sector. The coupling strength itself is subject to renormalization, of course. The scalar equivalence principle is violated only for objects for which either the graviton self-interaction or the scalar self-interaction is important--the first applies to black holes, while the second type of violation is avoided if the scalar is Galilean symmetric. PMID:21231444

Hui, Lam; Nicolis, Alberto

2010-12-01

85

Thermoelectrically cooled water trap  

DOEpatents

A water trap system based on a thermoelectric cooling device is employed to remove a major fraction of the water from air samples, prior to analysis of these samples for chemical composition, by a variety of analytical techniques where water vapor interferes with the measurement process. These analytical techniques include infrared spectroscopy, mass spectrometry, ion mobility spectrometry and gas chromatography. The thermoelectric system for trapping water present in air samples can substantially improve detection sensitivity in these analytical techniques when it is necessary to measure trace analytes with concentrations in the ppm (parts per million) or ppb (parts per billion) partial pressure range. The thermoelectric trap design is compact and amenable to use in a portable gas monitoring instrumentation.

Micheels, Ronald H. (Concord, MA)

2006-02-21

86

Charge trapping and detrapping in polymeric materials: Trapping parameters  

NASA Astrophysics Data System (ADS)

Space charge formation in polymeric materials can cause some serious concern for design engineers as the electric field may severely be distorted, leading to part of the material being overstressed. This may result in material degradation and possibly premature failure at the worst. It is therefore important to understand charge generation, trapping, and detrapping processes in the material. Trap depths and density of trapping states in materials are important as they are potentially related to microstructure of the material. Changes in these parameters may reflect the aging taken place in the material. In the present paper, characteristics of charge trapping and detrapping in low density polyethylene (LDPE) under dc electric field have been investigated using the pulsed electroacoustic (PEA) technique. A simple trapping and detrapping model based on two trapping levels has been used to qualitatively explain the observation. Numerical simulation based on the above model has been carried out to extract parameters related to trapping characteristics in the material. It has been found that the space charge decaying during the first few hundred seconds corresponding to the fast changing part of the slope was trapped with the shallow trap depth 0.88 eV, with trap density 1.47 × 1020 m-3 in the sample volume measured. At the same time, the space charge that decays at longer time corresponding to the slower part of the slope was trapped with the deep trap depth 1.01 eV, with its trap density 3.54 × 1018 m-3. The results also indicate that trap depths and density of both shallow and deep traps may be used as aging markers as changes in the material will certainly affect trapping characteristics in terms of trap depth and density.

Zhou, Tian-chun; Chen, George; Liao, Rui-jin; Xu, Zhiqiang

2011-08-01

87

Measurement of Trap Length for an Optical Trap  

NASA Technical Reports Server (NTRS)

The trap length along the beam axis for an optical trap formed with an upright, oil-immersion microscope was measured. The goals for this effort were twofold. It was deemed useful to understand the depth to which an optical trap can reach for purposes of developing a tool to assist in the fabrication of miniature devices. Additionally, it was desired to know whether the measured trap length favored one or the other of two competing theories to model an optical trap. The approach was to trap a microsphere of known size and mass and raise it from its initial trap position. The microsphere was then dropped by blocking the laser beam for a pre-determined amount of time. Dropping the microsphere in a free-fall mode from various heights relative to the coverslip provides an estimate of how the trapping length changes with depth in water in a sample chamber on a microscope slide. While it was not possible to measure the trap length with sufficient precision to support any particular theory of optical trap formation, it was possible to find regions where the presence of physical boundaries influenced optical traps, and determine that the trap length, for the apparatus studied, is between 6 and 7 m. These results allow more precise control using optical micromanipulation to assemble miniature devices by providing information about the distance over which an optical trap is effective.

Wrbanek, Susan Y.

2009-01-01

88

BEPS equivalency study. Final report  

SciTech Connect

To determine equivalency between the Florida Model Energy Efficiency Code for Building Construction (FMEEC) and the Federal Building Energy Performance Standards (BEPS). Commercial buildings and residential buildings were studied. The two codes were compared for equivalency for building types by calculating the estimated yearly energy consumption per square foot of conditioned floor area, for several reference buildings and several residences. Areas of differences were analyzed. A constant relationship existed between BEPS and FMEEC with respect to the commercial buildings, and residential buildings with minimal roof area.

Not Available

1983-02-01

89

Asymmetric ion trap  

DOEpatents

An ion trap having two end cap electrodes disposed asymmetrically about a center of a ring electrode. The inner surface of the end cap electrodes are conformed to an asymmetric pair of equipotential lines of the harmonic formed by the application of voltages to the electrodes. The asymmetry of the end cap electrodes allows ejection of charged species through the closer of the two electrodes which in turn allows for simultaneously detecting anions and cations expelled from the ion trap through the use of two detectors charged with opposite polarity.

Barlow, Stephan E. (Richland, WA); Alexander, Michael L. (Richland, WA); Follansbee, James C. (Pasco, WA)

1997-01-01

90

Children's Equivalence Judgments: Crossmapping Effects  

ERIC Educational Resources Information Center

Preschoolers made numerical comparisons between sets with varying degrees of shared surface similarity. When surface similarity was pitted against numerical equivalence (i.e., crossmapping), children made fewer number matches than when surface similarity was neutral (i.e, all sets contained the same objects). Only children who understood the…

Mix, Kelly S.

2008-01-01

91

Acquired Equivalence Changes Stimulus Representations  

ERIC Educational Resources Information Center

Acquired equivalence is a paradigm in which generalization is increased between two superficially dissimilar stimuli (or antecedents) that have previously been associated with similar outcomes (or consequents). Several possible mechanisms have been proposed, including changes in stimulus representations, either in the form of added associations or…

Meeter, M.; Shohamy, D.; Myers, C. E.

2009-01-01

92

Multiple Functions in Equivalence Classes  

ERIC Educational Resources Information Center

Four experiments examined the effects of training a "drawing" response to each of three stimuli in a 5-member equivalence class. In Experiment 1 the stimuli were an arbitrary word, a shape, or a mathematical symbol. Subjects then were trained to draw a separate component of a stickman at each of the 3 stimuli. Subsequent tests for function…

McVeigh, Brian; Keenan, Mickey

2009-01-01

93

Equivalent Pass/Fail Decisions.  

ERIC Educational Resources Information Center

Whether cutting score equivalents (CSEs) based on examinee performance are the same as CSEs based on expert judgment was examined using data from 3,262 examinees taking an internal medicine certification examination. CSEs produced by 40 physicians/experts were closer to the criteria than were standards derived from examinee performance. (SLD)

Norcini, John J.

1990-01-01

94

Representational Implications for Understanding Equivalence  

ERIC Educational Resources Information Center

Teachers and researchers have long recognized that students tend to misunderstand the equal sign as an operator; that is, a signal for "doing something" rather than a relational symbol of equivalence or quantity sameness. Students' equal sign misconception has been researched for more than thirty years (Weaver, 1971, 1973) with little refinement…

Capraro, Mary Margaret; Ding, Meixia; Matteson, Shirley; Capraro, Robert M.; Li, Xiaobao

2007-01-01

95

USEPA PATHOGEN EQUIVALENCY COMMITTEE RETREAT  

EPA Science Inventory

The Pathogen Equivalency Committee held its retreat from September 20-21, 2005 at Hueston Woods State Park in College Corner, Ohio. This presentation will update the PEC’s membership on emerging pathogens, analytical methods, disinfection techniques, risk analysis, preparat...

96

Entanglement of Trapped Ions  

Microsoft Academic Search

Entanglement, its generation, manipulation, measurement and fundamental understanding is at the very heart of quantum mechanics. We here report on the creation and characterization of entangled states of up to 8 trapped ions, the investigation of long-lived two-ion Bell-states and on experiments towards entangling ions and photons.

C. Becher; J. Benhelm; D. Chek-Al-Kar; M. Chwalla; W. Dür; O. Gühne; H. Häffner; W. Hänsel; T. Körber; A. Kreuter; G. P. T. Lancaster; T. Monz; E. S. Phillips; U. D. Rapol; M. Riebe; C. F. Roos; C. Russo; F. Schmidt-Kaler; R. Blatt

2005-01-01

97

Oil Formation and Trapping  

NSDL National Science Digital Library

This animation shows the successive stages in the formation of an oil reserve. In View 1, organic material settles, is buried, and is transformed by heat and pressure into oil. In View 2 an oil trap is formed: the area folds into an anticline, and oil migrates and accumulates in the anticline crest.

Stephen Marshak

98

Trapped Prairie Dog  

USGS Multimedia Gallery

A prairie dog trapped outside its burrow in Wind Cave National Park waits for a crew of scientists to arrive. The animal is part of a field test to determine the effectiveness of a USGS-developed oral sylvatic plague vaccine (SPV). This prairie dog will either be brought to a research van for blood ...

99

Prairie Dog in Trap  

USGS Multimedia Gallery

A prairie dog trapped outside its burrow in Wind Cave National Park waits for a crew of scientists to arrive. The animal is part of a field test to determine the effectiveness of a USGS-developed oral sylvatic plague vaccine (SPV). This prairie dog will either be brought to a research van for blood ...

100

Subsurface traps for impurities  

NASA Astrophysics Data System (ADS)

After considering the main contributions to the self-energy of a charged particle in a host lattice, an estimate of the strain energy is calculated which shows a minimum just under the surface for the case where the top layer is loosely bound to the rest of the crystal. Leading in this way to a subsurface trap.

Lagos, M.; Mahanty, J.; Slusarenko, V.

101

Subsurface traps for impurities  

NASA Astrophysics Data System (ADS)

After considering the main contributions to the self-energy of a charged particle in a host lattice, an estimate of the strain energy is calculated which shows a minimum just under the surface for the case where the top layer is loosely bound to the rest of the crystal. Leading in this way to a subsurface trap.

Lagos, M.; Mahanty, J.; Slusarenko, V.

1987-11-01

102

Build Your Own Insect Trap  

NSDL National Science Digital Library

Students design and construct devices to trap insects that are present in the area around the school. The objective is to ask the right design questions and conduct the right tests to determine if the traps work .

K-12 Rural Science Education Program,

103

Low interfacial trap density and sub-nm equivalent oxide thickness in In0.53Ga0.47As (001) metal-oxide-semiconductor devices using molecular beam deposited HfO2/Al2O3 as gate dielectrics  

NASA Astrophysics Data System (ADS)

We investigated the passivation of In0.53Ga0.47As (001) surface by molecular beam epitaxy techniques. After growth of strained In0.53Ga0.47As on InP (001) substrate, HfO2/Al2O3 high-? oxide stacks have been deposited in-situ after surface reconstruction engineering. Excellent capacitance-voltage characteristics have been demonstrated along with low gate leakage currents. The interfacial density of states (Dit) of the Al2O3/In0.53Ga0.47As interface have been revealed by conductance measurement, indicating a downward Dit profile from the energy close to the valence band (medium 1012 cm-2eV-1) towards that close to the conduction band (1011 cm-2eV-1). The low Dit's are in good agreement with the high Fermi-level movement efficiency of greater than 80%. Moreover, excellent scalability of the HfO2 has been demonstrated as evidenced by the good dependence of capacitance oxide thickness on the HfO2 thickness (dielectric constant of HfO2 ˜20) and the remained low Dit's due to the thin Al2O3 passivation layer. The sample with HfO2 (3.4 nm)/Al2O3 (1.2 nm) as the gate dielectrics has exhibited an equivalent oxide thickness of ˜0.93 nm.

Chu, L. K.; Merckling, C.; Alian, A.; Dekoster, J.; Kwo, J.; Hong, M.; Caymax, M.; Heyns, M.

2011-07-01

104

Elementary thermodynamics of trapped particles  

Microsoft Academic Search

I develop simple thermodynamic relations for a collection of noninteracting classical particles confined in a harmonic trap. The volume of such a trap is not a good thermodynamic variable, so conventional expressions of the first law of thermodynamics and the ideal gas law must be modified. I use the frequency of oscillations about the minimum of the trap as an

Martin Ligare

2002-01-01

105

AN AUTOMATED MOSQUITO COUNTING TRAP  

Technology Transfer Automated Retrieval System (TEKTRAN)

An automated mosquito counting trap has been designed and tested in laboratory cages. It employs a custom designed infrared beam sensor head retrofit into a commercial counter-flow technology trap (MM-X, American Biophysics Corp.). The trap provides time-stamped insect counts that can be downloaded...

106

SWD Trapping in New Hampshire  

E-print Network

SWD Trapping in New Hampshire Highbush Blueberries Alan T. Eaton UNH Cooperative Extension March if SWD traps are effective enough to tell when to spray blueberries. A. T. Eaton Sept 7, 2012 #12;A. T. Eaton 9/7/2012 #12;2012 ·Picking began about July 14 ·Set 2 SWD traps (New Engl. project) July 18

New Hampshire, University of

107

Transport quantum logic gates for trapped ions  

E-print Network

Many efforts are currently underway to build a device capable of large scale quantum information processing (QIP). Whereas QIP has been demonstrated for a few qubits in several systems, many technical difficulties must be overcome in order to construct a large-scale device. In one proposal for large-scale QIP, trapped ions are manipulated by precisely controlled light pulses and moved through and stored in multizone trap arrays. The technical overhead necessary to precisely control both the ion geometrical configurations and the laser interactions is demanding. Here we propose methods that significantly reduce the overhead on laser beam control for performing single and multiple qubit operations on trapped ions. We show how a universal set of operations can be implemented by controlled transport of ions through stationary laser beams. At the same time, each laser beam can be used to perform many operations in parallel, potentially reducing the total laser power necessary to carry out QIP tasks. The overall setup necessary for implementing transport gates is simpler than for gates executed on stationary ions. We also suggest a transport-based two-qubit gate scheme utilizing microfabricated permanent magnets that can be executed without laser light.

D. Leibfried; E. Knill; C. Ospelkaus; D. J. Wineland

2007-08-28

108

Available equivalent potential energy in moist atmospheres  

Microsoft Academic Search

Summary The equivalent potential energy of the moist atmosphere is defined as the sum of its total potential energy and latent heat. The available equivalent potential energy is the amount of equivalent potential energy available for conversion into kinetic energy. For the isolated moist atmospheres, we may find the equivalent lowest state which is the limit of the states attained

Y. L. McHall

1991-01-01

109

LED white light visual equivalence  

NASA Astrophysics Data System (ADS)

Current white LED color has a wide range of CCT and varying distance to Planckian Loci, which cause different tint in white color. This color variation keeps a number of illumination and indication applications away from LEDs. This article introduces a passive method, adding correction filters, to correct the color and achieve visual equivalence of the LED white light. Efficiency of using correction filters is discussed.

You, Chenhua

2004-10-01

110

EFFECT OF FILTER TEMPERATURE ON TRAPPING ZINC VAPOR  

SciTech Connect

To address the {sup 65}Zn contamination issue in the TEF, a multi-task experimental program was initiated. The first experimental task was completed and is reported in Ref. 1. The results of the second experimental task are reported here. This task examined the effect of filter temperature on trapping efficiency and deposit morphology. Based on the first experimental tasks that examined filter pore size and trapping efficiency, stainless steel filter media with a 20 {micro}m pore size was selected. A series of experiments using these filters was conducted during this second task to determine the effect of filter temperature on zinc vapor trapping efficiency, adhesion and morphology. The tests were conducted with the filters heated to 60, 120, and 200 C; the zinc source material was heated to 400 C for all the experiments to provide a consistent zinc source. The samples were evaluated for mass change, deposit adhesion and morphology. As expected from the physical vapor deposition literature, a difference in deposit morphology and appearance was observed between the three filter temperatures. The filter held at 60 C had the largest average mass gain while the 120 and 200 C filters exhibited similar but lower weight gains. The standard deviations were large and suggest that all three temperatures exhibited comparable gains. No zinc was detected on the backside surface of the filters indicating high efficiency for front and internal trapping. A zinc rich deposit was formed on the surface of the 60 C filter. Based on a simple tape adhesion test, the surface zinc was readily removed from the 60 C filter while less zinc deposit was removed from the 120 and 200 C filter samples. It is surmised that the higher temperatures enable the zinc to deposit within the filter media rather than on the surface. Based on the findings that all three statistically trapped the same quantity of zinc vapor and that the higher temperatures resulted in a more adherent/better trapped product, operating the filters at 120 to 200 C is recommended.

Korinko, P.

2011-03-25

111

Task Communication in DEMOS  

Microsoft Academic Search

This paper describes the fundamentals and some of the details of task communication in DEMOS, the operating system for the CRAY-I computer being developed at the Los Alamos Scientific Laboratory. The communication mechan- ism is a message system with several novel features. Messages are sent from one task to another over links. Links are the primary protected objects in the

Forest Baskett; John H. Howard; John T. Montague

1977-01-01

112

Task Description Language  

NASA Technical Reports Server (NTRS)

Task Description Language (TDL) is an extension of the C++ programming language that enables programmers to quickly and easily write complex, concurrent computer programs for controlling real-time autonomous systems, including robots and spacecraft. TDL is based on earlier work (circa 1984 through 1989) on the Task Control Architecture (TCA). TDL provides syntactic support for hierarchical task-level control functions, including task decomposition, synchronization, execution monitoring, and exception handling. A Java-language-based compiler transforms TDL programs into pure C++ code that includes calls to a platform-independent task-control-management (TCM) library. TDL has been used to control and coordinate multiple heterogeneous robots in projects sponsored by NASA and the Defense Advanced Research Projects Agency (DARPA). It has also been used in Brazil to control an autonomous airship and in Canada to control a robotic manipulator.

Simmons, Reid; Apfelbaum, David

2005-01-01

113

Clustered Multi-Task Learning Via Alternating Structure Optimization  

PubMed Central

Multi-task learning (MTL) learns multiple related tasks simultaneously to improve generalization performance. Alternating structure optimization (ASO) is a popular MTL method that learns a shared low-dimensional predictive structure on hypothesis spaces from multiple related tasks. It has been applied successfully in many real world applications. As an alternative MTL approach, clustered multi-task learning (CMTL) assumes that multiple tasks follow a clustered structure, i.e., tasks are partitioned into a set of groups where tasks in the same group are similar to each other, and that such a clustered structure is unknown a priori. The objectives in ASO and CMTL differ in how multiple tasks are related. Interestingly, we show in this paper the equivalence relationship between ASO and CMTL, providing significant new insights into ASO and CMTL as well as their inherent relationship. The CMTL formulation is non-convex, and we adopt a convex relaxation to the CMTL formulation. We further establish the equivalence relationship between the proposed convex relaxation of CMTL and an existing convex relaxation of ASO, and show that the proposed convex CMTL formulation is significantly more efficient especially for high-dimensional data. In addition, we present three algorithms for solving the convex CMTL formulation. We report experimental results on benchmark datasets to demonstrate the efficiency of the proposed algorithms. PMID:25328366

Zhou, Jiayu; Chen, Jianhui; Ye, Jieping

2013-01-01

114

Acoustic rainbow trapping  

PubMed Central

Spatial modulation of sound velocity below the wavelength scale can introduce strong frequency-dependent acoustic responses in tailored composite materials, regardless the fact that most natural bulk materials have negligible acoustic dispersions. Here, for the first time, we experimentally demonstrate a metamaterial that traps broadband acoustic waves and spatially separates different frequency components, as the result of dispersion and wave velocity control by designed gradient subwavelength structures. The trapping positions can be predicted by the microscopic picture of balanced interplay between the acoustic resonance inside individual apertures and the mutual coupling among them. With the enhanced wave-structure interactions and the tailored frequency responses, such metamaterial allows precise spatial-spectral control of acoustic waves and opens new venue for high performance acoustic wave sensing, filtering, and nondestructive metrology.

Zhu, Jie; Chen, Yongyao; Zhu, Xuefeng; Garcia-Vidal, Francisco J.; Yin, Xiaobo; Zhang, Weili; Zhang, Xiang

2013-01-01

115

Atom Trap Trace Analysis  

NASA Astrophysics Data System (ADS)

Since the invention of radiocarbon dating in 1949, trace analyses of long-lived cosmogenic isotopes have contributed to a wide range of scientific and technological areas. We have developed an analytical method called Atom Trap Trace Analysis (ATTA), in which individual atoms of the desired isotope are selectively captured and detected with a magneto-optical trap. ATTA possesses a superior selectivity and is used to analyze environmental radio-isotopes: ^81Kr, ^85Kr, and ^39Ar. These three isotopes have extremely low isotopic abundances in the range of 10-16 - 10-11, and cover a wide range of ages and applications. This work is supported by DOE, Office of Nuclear Physics, and by NSF, Division of Earth Sciences.

Lu, Zheng-Tian

2011-06-01

116

Harmonically trapped jellium  

E-print Network

We discuss the model of a $D$-dimensional confined electron gas in which the particles are trapped by a harmonic potential. In particular, we study the non-interacting kinetic and exchange energies of finite-size inhomogeneous systems, and compare the resulting Thomas-Fermi and Dirac coefficients with various uniform electron gas paradigms. We show that, in the thermodynamic limit, the properties of this model are identical to those of the $D$-dimensional Fermi gas.

Loos, Pierre-François

2012-01-01

117

Magnetic trap for thulium atoms  

SciTech Connect

For the first time ultra-cold thulium atoms were trapped in a magnetic quadrupole trap with a small field gradient (20 Gs cm{sup -1}). The atoms were loaded from a cloud containing 4x10{sup 5} atoms that were preliminarily cooled in a magneto-optical trap to the sub-Doppler temperature of 80 {mu}K. As many as 4x10{sup 4} atoms were trapped in the magnetic trap at the temperature of 40 {mu}K. By the character of trap population decay the lifetime of atoms was determined (0.5 s) and an upper estimate was obtained for the rate constant of inelastic binary collisions for spin-polarised thulium atoms in the ground state (g{sub in} < 10{sup -11}cm{sup 3} s{sup -1}). (magnetic traps)

Sukachev, D D; Sokolov, A V; Chebakov, K A; Akimov, A V; Kolachevskii, N N; Sorokin, Vadim N [P N Lebedev Physical Institute, Russian Academy of Sciences, Moscow (Russian Federation)

2011-08-31

118

In-Trap Spectroscopy of Charge-Bred Radioactive Ions  

NASA Astrophysics Data System (ADS)

In this Letter, we introduce the concept of in-trap nuclear decay spectroscopy of highly charged radioactive ions and describe its successful application as a novel spectroscopic tool. This is demonstrated by a measurement of the decay properties of radioactive mass A=124 ions (here, In124 and Cs124) in the electron-beam ion trap of the TITAN facility at TRIUMF. By subjecting the trapped ions to an intense electron beam, the ions are charge bred to high charge states (i.e., equivalent to the removal of N-shell electrons), and an increase of storage times to the level of minutes without significant ion losses is achieved. The present technique opens the venue for precision spectroscopy of low branching ratios and is being developed in the context of measuring electron-capture branching ratios needed for determining the nuclear ground-state properties of the intermediate odd-odd nuclei in double-beta (??) decay.

Lennarz, A.; Grossheim, A.; Leach, K. G.; Alanssari, M.; Brunner, T.; Chaudhuri, A.; Chowdhury, U.; Crespo López-Urrutia, J. R.; Gallant, A. T.; Holl, M.; Kwiatkowski, A. A.; Lassen, J.; Macdonald, T. D.; Schultz, B. E.; Seeraji, S.; Simon, M. C.; Andreoiu, C.; Dilling, J.; Frekers, D.

2014-08-01

119

Equivalent source magnetic dipoles revisited  

NASA Astrophysics Data System (ADS)

Equivalent point source inversion in the rectangular coordinate system has been widely used to reduce satellite magnetic data collected at different altitudes to a common elevation over small areas. This method is based on the expression of the magnetic anomaly caused by a magnetic dipole. Such an expression derived in a spherical coordinate system by von Frese et al. [1981] is found erroneous. We point out the errors in von Frese et al.'s [1981] formulas and present the correct expression for the magnetic field of a magnetic dipole in a spherical coordinate system.

Dyment, J.; Arkani-Hamed, J.

120

Optical trapping of anisotropic nanocylinder  

NASA Astrophysics Data System (ADS)

The T-matrix method with the Vector Spherical Wave Function (VSWF) expansions represents some difficulties for computing optical scattering of anisotropic particles. As the divergence of the electric field is nonzero in the anisotropic medium and the VSWFs do not satisfy the anisotropic wave equations one questioned whether the VSWFs are still a suitable basis in the anisotropic medium. We made a systematic and careful review on the vector basis functions and the VSWFs. We found that a field vector in Euclidean space can be decomposed to triplet vectors {L, M, N}, which as non-coplanar. Especially, the vector L is designed to represent non-zero divergence component of the vector solution, so that the VSWF basis is sufficiently general to represent the solutions of the anisotropic wave equation. The mathematical proof can be that when the anisotropic wave equations is solved in the Fourier space, the solution is expanded in the basis of the plan waves with angular spectrum amplitude distributions. The plane waves constitute an orthogonal and complete set for the anisotropic solutions. Furthermore, the plane waves are expanded into the VSWF basis. These two-step expansions are equivalent to the one-step direct expansion of the anisotropic solution to the VSWF basis. We used direct VSWF expansion, along with the point-matching method in the T-matrix, and applied the boundary condition to the normal components displacement field in order to compute the stress and the related forces and torques and to show the mechanism of the optical trap of the anisotropic nano-cylinders.

Bareil, Paul B.; Sheng, Yunlong

2013-09-01

121

Task context impacts visual object processing differentially across the cortex.  

PubMed

Perception reflects an integration of "bottom-up" (sensory-driven) and "top-down" (internally generated) signals. Although models of visual processing often emphasize the central role of feed-forward hierarchical processing, less is known about the impact of top-down signals on complex visual representations. Here, we investigated whether and how the observer's goals modulate object processing across the cortex. We examined responses elicited by a diverse set of objects under six distinct tasks, focusing on either physical (e.g., color) or conceptual properties (e.g., man-made). Critically, the same stimuli were presented in all tasks, allowing us to investigate how task impacts the neural representations of identical visual input. We found that task has an extensive and differential impact on object processing across the cortex. First, we found task-dependent representations in the ventral temporal and prefrontal cortex. In particular, although object identity could be decoded from the multivoxel response within task, there was a significant reduction in decoding across tasks. In contrast, the early visual cortex evidenced equivalent decoding within and across tasks, indicating task-independent representations. Second, task information was pervasive and present from the earliest stages of object processing. However, although the responses of the ventral temporal, prefrontal, and parietal cortex enabled decoding of both the type of task (physical/conceptual) and the specific task (e.g., color), the early visual cortex was not sensitive to type of task and could only be used to decode individual physical tasks. Thus, object processing is highly influenced by the behavioral goal of the observer, highlighting how top-down signals constrain and inform the formation of visual representations. PMID:24567402

Harel, Assaf; Kravitz, Dwight J; Baker, Chris I

2014-03-11

122

Task context impacts visual object processing differentially across the cortex  

PubMed Central

Perception reflects an integration of “bottom-up” (sensory-driven) and “top-down” (internally generated) signals. Although models of visual processing often emphasize the central role of feed-forward hierarchical processing, less is known about the impact of top-down signals on complex visual representations. Here, we investigated whether and how the observer’s goals modulate object processing across the cortex. We examined responses elicited by a diverse set of objects under six distinct tasks, focusing on either physical (e.g., color) or conceptual properties (e.g., man-made). Critically, the same stimuli were presented in all tasks, allowing us to investigate how task impacts the neural representations of identical visual input. We found that task has an extensive and differential impact on object processing across the cortex. First, we found task-dependent representations in the ventral temporal and prefrontal cortex. In particular, although object identity could be decoded from the multivoxel response within task, there was a significant reduction in decoding across tasks. In contrast, the early visual cortex evidenced equivalent decoding within and across tasks, indicating task-independent representations. Second, task information was pervasive and present from the earliest stages of object processing. However, although the responses of the ventral temporal, prefrontal, and parietal cortex enabled decoding of both the type of task (physical/conceptual) and the specific task (e.g., color), the early visual cortex was not sensitive to type of task and could only be used to decode individual physical tasks. Thus, object processing is highly influenced by the behavioral goal of the observer, highlighting how top-down signals constrain and inform the formation of visual representations. PMID:24567402

Harel, Assaf; Kravitz, Dwight J.; Baker, Chris I.

2014-01-01

123

Unexpected equivalent-oxide-thickness dependence of the subthreshold swing in tunnel field-effect transistors  

NASA Astrophysics Data System (ADS)

Tunnel field-effect transistors (TFETs) exhibiting a minimum subthreshold swing (SS) of 27 mV/decade were successfully fabricated using conventional planar HfO2/Si-gate-stack structures. However, an unexpected SS degradation with increasing equivalent oxide thickness (EOT) was observed compared with the simulated results obtained under the assumption of ideal band-to-band tunneling. We found that the poor subthreshold operation was governed by a thermally activated process, suggesting trap-assisted tunneling that occurs with traps near the metallurgical pn junction. Furthermore, we discuss the effect of the observed EOT-sensitive SS degradation on device production.

Mori, Takahiro; Yasuda, Tetsuji; Fukuda, Koichi; Morita, Yukinori; Migita, Shinji; Tanabe, Akihito; Maeda, Tatsuro; Mizubayashi, Wataru; O'uchi, Shin-ichi; Liu, Yongxun; Masahara, Meishoku; Miyata, Noriyuki; Ota, Hiroyuki

2014-02-01

124

Equivalent-circuit model for vacuum ultraviolet irradiation of dielectric films  

SciTech Connect

Vacuum ultraviolet (VUV) irradiation, which occurs during plasma processing, causes photoemission of electrons from the dielectrics. Photoemission primarily occurs from defect states in the band gap of the dielectric and results in trapped positive charges. The trapped positive charges are negated by photoinjection of electrons from the underlying substrate into the dielectric. The authors propose an equivalent-circuit model using with which, once the circuit parameters are determined, charging of dielectric materials under VUV irradiation can be predicted. The circuit includes a dielectric capacitor, the intrinsic and photo conductivities of the dielectric and substrate, and the processes of photoemission and photoinjection.

Sinha, Harsh; Shohet, J. Leon [Plasma Processing and Technology Laboratory and Department of Electrical and Computer Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706 (United States)

2012-05-15

125

Electromyographic effects of ergonomic modifications in selected meatpacking tasks.  

PubMed

This project evaluated the feasibility of a new method of collection of electromyographic (EMG) data during working conditions in industry, and quantified the effects of specific job modifications on the EMG activity of selected upper extremity muscle groups. Average root mean square (RMS) surface EMG activity, calibrated to force equivalent units, was collected on 20 workers from three pork processing tasks before and after ergonomic modifications to their tasks. Significant reductions in muscle effort were detected in the biceps and/or wrist and finger flexors after modification for two of the three tasks. This EMG measurement technique can be used to objectively validate reduced muscle effort with ergonomic modifications. PMID:10327086

Cook, T M; Ludewig, P M; Rosecrance, J C; Zimmermann, C L; Gerleman, D G

1999-06-01

126

TecTask  

NSDL National Science Digital Library

The Task Group on Tectonics and Structural Geology (TecTask) is a committee of the IUGS that represents an initiative of earth scientists dedicated to stimulating communication and coordination within the international science community and to providing information to the public. The site features links to conferences, data, and downloadable software, as well as journals, organizations and societies dedicated to various aspects of structural geology.

The Task Group on Tectonics and Structural Geology (TecTask); Tectask

127

Atom trap trace analysis  

SciTech Connect

A new method of ultrasensitive trace-isotope analysis has been developed based upon the technique of laser manipulation of neutral atoms. It has been used to count individual {sup 85}Kr and {sup 81}Kr atoms present in a natural krypton sample with isotopic abundances in the range of 10{sup {minus}11} and 10{sup {minus}13}, respectively. The atom counts are free of contamination from other isotopes, elements,or molecules. The method is applicable to other trace-isotopes that can be efficiently captured with a magneto-optical trap, and has a broad range of potential applications.

Lu, Z.-T.; Bailey, K.; Chen, C.-Y.; Du, X.; Li, Y.-M.; O'Connor, T. P.; Young, L.

2000-05-25

128

ATRAP - Progress Towards Trapped Antihydrogen  

SciTech Connect

The ATRAP experiment at the CERN antiproton decelerator AD aims for a test of the CPT invariance by a high precision comparison of the 1s-2s transition in the hydrogen and the antihydrogen atom.Antihydrogen production is routinely operated at ATRAP and detailed studies have been performed in order to optimize the production efficiency of useful antihydrogen.For high precision measurements of atomic transitions cold antihydrogen in the ground state is required which must be trapped due to the low number of available antihydrogen atoms compared to the cold hydrogen beam used for hydrogen spectroscopy. To ensure a reasonable antihydrogen trapping efficiency a magnetic trap has to be superposed the nested Penning trap. First trapping tests of charged particles within a combined magnetic/Penning trap have started at ATRAP.

Grzonka, D.; Goldenbaum, F.; Oelert, W.; Sefzick, T.; Zhang, Z. [IKP, Forschungszentrum Juelich GmbH, 52425 Juelich (Germany); Comeau, D.; Hessels, E.A.; Storry, C.H. [York University, Department of Physics and Astronomy, Toronto, Ontario M3J 1P3 (Canada); Gabrielse, G.; Larochelle, P.; Lesage, D.; Levitt, B.; Speck, A. [Department of Physics, Harvard University, Cambridge, MA 02138 (United States); Haensch, T.W. [Max-Planck-Institut fuer Quantenoptik, Hans-Kopfermann-Strasse 1, 85748 Garching (Germany); Ludwig-Maximilians-Universitaet Muenchen, Schellingstrasse 4/III, 80799 Munich (Germany); Pittner, H.; Walz, J. [Max-Planck-Institut fuer Quantenoptik, Hans-Kopfermann-Strasse 1, 85748 Garching (Germany)

2005-10-26

129

Build a Fruit Fly Trap  

NSDL National Science Digital Library

In this construction activity, students use a 2-liter bottle to build a fly trap. There is not much supporting information besides the directions, but the trap can be used to examine fly behavior, and it might also be redesigned by students. In the construction part of the activity, younger learners will need help and supervision from an older learner or adult, but any age learner can do independent observation of fly behavior once insects are inside the trap.

Wisconsin-Madison, Universitiy O.

2007-01-01

130

Task Switching in a Hierarchical Task Structure: Evidence for the Fragility of the Task Repetition Benefit  

ERIC Educational Resources Information Center

This study examined how task switching is affected by hierarchical task organization. Traditional task-switching studies, which use a constant temporal and spatial distance between each task element (defined as a stimulus requiring a response), promote a flat task structure. Using this approach, Experiment 1 revealed a large switch cost of 238 ms.…

Lien, Mei-Ching; Ruthruff, Eric

2004-01-01

131

Software development for a fluid portable ion trap mass spectrometer  

SciTech Connect

Most mass spectrometer data systems are developed and optimized for the benchtop GC/MS market and thus do not adequately address the requirements for direct sampling methods. Field analysis also places greater demands on real-time data processing including automated interpretation and quantification for target analytes. The current field portable ion trap mass spectrometers developed at ORNL are based on the Finnigan Magnum ion trap mass spectrometer which provides a procedure language for user programs. A series of these procedures has been developed to support direct sampling ion trap mass spectrometry studies and is part of an overall software development strategy to address the needs of these direct sampling instruments for rapid field analysis and process monitoring. The general approach has been to create task oriented menus that lead a user through a complete analysis. Thus, the user is focused on completing tasks rather than learning and using all of the software components to complete the task. Additionally, user input has been minimized to save keyboard input and data logging time.

Hart, K.J.; Buchanan, M.V.; Wise, M.B. [Oak Ridge National Lab., TN (United States)

1994-12-31

132

Gated charged-particle trap  

DOEpatents

The design and operation of a new type of charged-particle trap provides simultaneous measurements of mass, charge, and velocity of large electrospray ions. The trap consists of a detector tube mounted between two sets of center-bored trapping plates. Voltages applied to the trapping plates define symmetrically-opposing potential valleys which guide axially-injected ions to cycle back and forth through the charge-detection tube. A low noise charge-sensitive amplifier, connected to the tube, reproduces the image charge of individual ions as they pass through the detector tube. Ion mass is calculated from measurement of ion charge and velocity following each passage through the detector.

Benner, W. Henry (Danville, CA)

1999-01-01

133

Organic magnetoresistance from deep traps  

NASA Astrophysics Data System (ADS)

We predict that singly occupied carrier traps, produced by electrical stress or irradiation within organic semiconductors, can cause spin blockades and the large room-temperature magnetoresistance known as organic magnetoresistance. The blockade occurs because many singly occupied traps can only become as doubly occupied in a spin-singlet configuration. Magnetic-field effects on spin mixing during transport dramatically modify the effects of this blockade and produce magnetoresistance. We calculate the quantitative effects of these traps on organic magnetoresistance from percolation theory and find a dramatic nonlinear dependence of the saturated magnetoresistance on trap density, leading to values ˜ 20%, within the theory's range of validity.

Harmon, N. J.; Flatté, M. E.

2014-07-01

134

DNA Separation Using Photoelectrophoretic Traps  

SciTech Connect

In our recent publications we presented a design that allows formation of highly localized and optically controlled electrophoretic traps. 1,2 We demonstrated that electrophoretic traps can be utilized for biomolecule photoconcentration, optically directed transport, and separation by size. 1,2 In the current publication we suggest a hybrid design for biomolecule separation which implements electrophoretic traps in tandem with well-established electrophoretic techniques. We perform Monte Carlo simulations that demonstrate that the resolution of well-established electrophoretic techniques can be greatly enhanced by introducing photoelectrophoretic traps.

Braiman, Avital [ORNL; Thundat, Thomas George [ORNL; Rudakov, Fedor M [ORNL

2011-01-01

135

Undecidable Equivalences for Basic Process Algebra  

E-print Network

Q Q Q Q Qs \\Gamma \\Gamma \\Gamma \\Gamma \\Gamma\\Psi Simulation equivalence \\Gamma \\Gamma \\Gamma \\Gamma \\Gamma \\Gamma \\Gamma \\Gamma \\Gamma \\Gamma \\Gamma \\Gamma \\Gamma \\Gamma\\Psi Possible­futures equivalence J as an observa­ tional equivalence have used unnatural operators. In [1] global testing operators were #12; 3

Hüttel, Hans

136

Single-atom trapping in holographic 2D arrays of microtraps with arbitrary geometries  

E-print Network

We demonstrate single-atom trapping in two-dimensional arrays of microtraps with arbitrary geometries. We generate the arrays using a Spatial Light Modulator (SLM), with which we imprint an appropriate phase pattern on an optical dipole trap beam prior to focusing. We trap single $^{87}{\\rm Rb}$ atoms in the sites of arrays containing up to $\\sim100$ microtraps separated by distances as small as $3\\;\\mu$m, with complex structures such as triangular, honeycomb or kagome lattices. Using a closed-loop optimization of the uniformity of the trap depths ensures that all trapping sites are equivalent. This versatile system opens appealing applications in quantum information processing and quantum simulation, e.g. for simulating frustrated quantum magnetism using Rydberg atoms.

Nogrette, Florence; Ravets, Sylvain; Barredo, Daniel; Béguin, Lucas; Vernier, Aline; Lahaye, Thierry; Browaeys, Antoine

2014-01-01

137

Single-atom trapping in holographic 2D arrays of microtraps with arbitrary geometries  

E-print Network

We demonstrate single-atom trapping in two-dimensional arrays of microtraps with arbitrary geometries. We generate the arrays using a Spatial Light Modulator (SLM), with which we imprint an appropriate phase pattern on an optical dipole trap beam prior to focusing. We trap single $^{87}{\\rm Rb}$ atoms in the sites of arrays containing up to $\\sim100$ microtraps separated by distances as small as $3\\;\\mu$m, with complex structures such as triangular, honeycomb or kagome lattices. Using a closed-loop optimization of the uniformity of the trap depths ensures that all trapping sites are equivalent. This versatile system opens appealing applications in quantum information processing and quantum simulation, e.g. for simulating frustrated quantum magnetism using Rydberg atoms.

Florence Nogrette; Henning Labuhn; Sylvain Ravets; Daniel Barredo; Lucas Béguin; Aline Vernier; Thierry Lahaye; Antoine Browaeys

2014-02-21

138

Task Performance & Eye Activity 1 Task Performance and Eye Activity  

E-print Network

the dual task the mean pupil diameter and horizontal vergence increased when subjects performed wellTask Performance & Eye Activity 1 Task Performance and Eye Activity: Predicting Behavior Relating of California, San Diego, San Diego, CA Running Head: Task Performance & Eye Activity Abstract word count: 254

Makeig, Scott

139

Lobster Trap at Reed Point  

USGS Multimedia Gallery

A lobster trap buoy rides in the waves of Seal Cove at Reed Point, along the southwestern coast of Mount Desert Island. Lobster traps rest at the bottom of the sea and are tethered to a buoy that marks their location....

140

Mass trapping for Anastrepha suspensa  

Technology Transfer Automated Retrieval System (TEKTRAN)

Mass trapping has been found to be highly effective for control of pest fruit flies when populations are low and a highly effective lure is available for the target species. Successful population control through mass trapping is an indicator that attract-and-kill bait stations may be equally succes...

141

Managing the Steam Trap Population  

E-print Network

administers all aspects of the program including the technical expertise to size, select, apply, install and maintain the stel\\m trap population. Having a reporting system: The data is com puterized and keeps track of each time a trap is inspected...

Atlas, R. D.

1983-01-01

142

Quantum computing with trapped ions  

SciTech Connect

The significance of quantum computation for cryptography is discussed. Following a brief survey of the requirements for quantum computational hardware, an overview of the ion trap quantum computation project at Los Alamos is presented. The physical limitations to quantum computation with trapped ions are analyzed and an assessment of the computational potential of the technology is made.

Hughes, R.J.

1998-01-01

143

Nontoxic Antifreeze for Insect Traps  

Technology Transfer Automated Retrieval System (TEKTRAN)

Propylene glycol in water is a safe and effective alternative to ethylene glycol as a capture liquid in insect traps (pitfalls, flight intercepts, pan traps). Propylene glycol formulations are readily available because it is the primary (95%) ingredient in certain automotive antifreeze formulations...

144

Auditory-Visual and Visual-Visual Equivalence Relations in Children  

ERIC Educational Resources Information Center

Previous research has suggested that persons with mental retardation evidence equivalence more readily after being trained on auditory-visual than on visual-visual match-to-sample tasks. The present study sought to determine if this discrepancy is also apparent in normally capable preschoolers and whether the derived class-consistent test…

Smeets, Paul M.; Barnes-Holmes, Dermot

2005-01-01

145

Effects of a CARO on Stimulus Equivalence Formation: A Systematic Replication  

ERIC Educational Resources Information Center

In two experiments, we examined the disruptive effects of a "can't answer" response option (CARO) on equivalence formation. The first experiment was a systematic replication of Duarte, Eikeseth, Rosales-Ruiz, and Baer (1998), in which participants in a CARO group and a No-CARO group performed conditional discrimination tasks with abstract stimuli…

Imam, Abdulrazaq A.; Blanche, Justin V.

2013-01-01

146

Articulating Syntactic and Numeric Perspectives on Equivalence: The Case of Rational Expressions  

ERIC Educational Resources Information Center

Our study concerns the conceptual mathematical knowledge that emerges during the resolution of tasks on the equivalence of polynomial and rational algebraic expressions, by using CAS and paper-and-pencil techniques. The theoretical framework we adopt is the Anthropological Theory of Didactics ("Chevallard" 19:221-266, 1999), in…

Solares, Armando; Kieran, Carolyn

2013-01-01

147

Segmented trapped vortex cavity  

NASA Technical Reports Server (NTRS)

An annular trapped vortex cavity assembly segment comprising includes a cavity forward wall, a cavity aft wall, and a cavity radially outer wall there between defining a cavity segment therein. A cavity opening extends between the forward and aft walls at a radially inner end of the assembly segment. Radially spaced apart pluralities of air injection first and second holes extend through the forward and aft walls respectively. The segment may include first and second expansion joint features at distal first and second ends respectively of the segment. The segment may include a forward subcomponent including the cavity forward wall attached to an aft subcomponent including the cavity aft wall. The forward and aft subcomponents include forward and aft portions of the cavity radially outer wall respectively. A ring of the segments may be circumferentially disposed about an axis to form an annular segmented vortex cavity assembly.

Grammel, Jr., Leonard Paul (Inventor); Pennekamp, David Lance (Inventor); Winslow, Jr., Ralph Henry (Inventor)

2010-01-01

148

Enhancer trapping in plants.  

PubMed

Advances in sequencing technology have led to the availability of complete genome sequences of many different plant species. In order to make sense of this deluge of information, functional genomics efforts have been intensified on many fronts. With improvements in plant transformation technologies, T-DNA and/or transposon-based gene and enhancer-tagged populations in various crop species are being developed to augment functional annotation of genes and also to help clone important genes. State-of-the-art cloning and sequencing technologies, which would help identify T-DNA or transposon junction sequences in large genomes, have also been initiated. This chapter gives a brief history of enhancer trapping and then proceeds to describe gene and enhancer tagging in plants. The significance of reporter gene fusion populations in plant genomics, especially in important cereal crops, is discussed. PMID:21181537

Chudalayandi, Sivanandan

2011-01-01

149

Thermal Replication Trap  

NASA Astrophysics Data System (ADS)

The hallmark of living matter is the replication of genetic molecules and their active storage against diffusion. We have argued in the past that thermal convection can host the million-fold accumulation even of single nucleotides and at the same time trigger exponential replication [1]. Accumulation is driven by thermophoresis and convection in elongated chambers, replication by the inherent temperature cycling in convection. Optothermal pumping [2,3] allows to implement the thermal trap efficiently in a toroidal [4] or linear [5] geometry. Based on this method, we were in a position to combine accumulation and replication of DNA in the same chamber [5]. As we are missing a solid chemistry of prebiotic replication, we used as a proxy reaction for to replication the polymerase chain reaction. Convective flow both drives the DNA replicating polymerase chain reaction (PCR) while concurrent thermophoresis accumulates the replicated 143 base pair DNA in bulk solution. The time constant for accumulation is 92 s while DNA is doubled every 50 s. The length of the amplified DNA is checked with thermophoresis. Finite element simulations confirm the findings. The experiments explore conditions in pores of hydrothermal rock which can serve as a model environment for the origin of life and has prospects towards the first autonomous evolution, hosting the Darwin process by molecular selection using the thermophoretic trap. On the other side, the implemented continuous evolution will be able to breed well specified DNA or RNA molecules in the future. [4pt] [1] Baaske, Weinert, Duhr, Lemke, Russell and Braun, PNAS 104, 9346 (2007) [0pt] [2] Weinert, Kraus, Franosch and Braun, PRL 100, 164501 (2008) [0pt] [3] Weinert and Braun, Journal of Applied Physics 104, 104701 (2008) [0pt] [4] Weinert and Braun, Nano Letters 9, 4264 (2009) [0pt] [5] Mast and Braun, PRL 104, 188102 (2010)

Braun, Dieter

2011-03-01

150

Tsunami trapping near circular islands  

NASA Astrophysics Data System (ADS)

Trapping of long water waves that are induced by submarine earthquakes and that attack circular islands is studied by applying a theoretical model ( Tinti and Vannini, 1994) that is based on the linear shallow water approximation. The solution is computed as the superposition of the eigenmodes of the water basin. The tsunami trapping is seen in terms of the capability of the source to excite the “trapped” eigenmodes of the basin. The bottom depth dependence around the island is shown to be quite important in determining the trapping capability of the island: a depth profile that is downwardly concave as the distance from the island coasts increases is substantially more efficient in amplifying the incoming waves and in trapping their energy than a profile exhibiting an upward concavity.

Tinti, Stefano; Vannini, Cesare

1995-09-01

151

Impact of Static Graphics, Animated Graphics and Mental Imagery on a Complex Learning Task  

ERIC Educational Resources Information Center

The present study compared the impact of different categories of graphics used within a complex learning task. One hundred eighty five native English speaking undergraduates participated in a task that required learning 18 Chinese radicals and their English equivalent translations. A post-test only control group design compared performance…

Lai, Feng-Qi; Newby, Timothy J.

2012-01-01

152

WhichHighSchoolEquivalencyProgramisRightforYou? Which LaGuardia High School Equivalency  

E-print Network

WhichHighSchoolEquivalencyProgramisRightforYou? Which LaGuardia High School Equivalency Program is Right for You? DidYouKnow? LaGuardia Community College is an official High School Equivalency Testing Center I want to start the high school equivalency program in English during the daytime, evening

Rosen, Jay

153

It Pays to Be Organized: Organizing Arithmetic Practice around Equivalent Values Facilitates Understanding of Math Equivalence  

ERIC Educational Resources Information Center

This experiment tested the hypothesis that organizing arithmetic fact practice by equivalent values facilitates children's understanding of math equivalence. Children (M age = 8 years 6 months, N = 104) were randomly assigned to 1 of 3 practice conditions: (a) equivalent values, in which problems were grouped by equivalent sums (e.g., 3 + 4 = 7, 2…

McNeil, Nicole M.; Chesney, Dana L.; Matthews, Percival G.; Fyfe, Emily R.; Petersen, Lori A.; Dunwiddie, April E.; Wheeler, Mary C.

2012-01-01

154

Skill Components of Task Analysis  

ERIC Educational Resources Information Center

Some task analysis methods break down a task into a hierarchy of subgoals. Although an important tool of many fields of study, learning to create such a hierarchy (redescription) is not trivial. To further the understanding of what makes task analysis a skill, the present research examined novices' problems with learning Hierarchical Task…

Adams, Anne E.; Rogers, Wendy A.; Fisk, Arthur D.

2013-01-01

155

Theory and application of planar ion traps  

E-print Network

In this thesis, we investigate a new geometry of Paul trap with electrodes in a plane. These planar ion traps are compatible with modern silicon microfabrication, and can be scaled up to large arrays with multiple trapping ...

Pearson, Christopher Elliott

2006-01-01

156

Microprocessor multi-task monitor  

SciTech Connect

This paper describes a multi-task monitor program for microprocessors. Although written for the Intel 8085, it incorporates features that would be beneficial for implementation in other microprocessors used in controlling and monitoring experiments and accelerators. The monitor places permanent programs (tasks) arbitrarily located throughout ROM in a priority ordered queue. The programmer is provided with the flexibility to add new tasks or modified versions of existing tasks, without having to comply with previously defined task boundaries or having to reprogram all of ROM. Scheduling of tasks is triggered by timers, outside stimuli (interrupts), or inter-task communications. Context switching time is of the order of tenths of a milllisecond.

Ludemann, C.A.

1983-01-01

157

Scenarios and task analysis  

Microsoft Academic Search

A Critical Review of Carroll's book on scenario-based design is offered [Making Use: Scenario-Based Design of Human–Computer Interactions (2000)]. Carroll characterises scenarios as ‘stories about use’. The paper demonstrates that Carroll's proposals about scenarios and their use in software engineering can be fitted into the broader framework of task analysis in Human–Computer Interaction.

Dan Diaper

2002-01-01

158

Creating Positive Task Constraints  

ERIC Educational Resources Information Center

Constraints are characteristics of the individual, the task, or the environment that mold and shape movement choices and performances. Constraints can be positive--encouraging proficient movements or negative--discouraging movement or promoting ineffective movements. Physical educators must analyze, evaluate, and determine the effect various…

Mally, Kristi K.

2006-01-01

159

Biomedical applications engineering tasks  

NASA Technical Reports Server (NTRS)

The engineering tasks performed in response to needs articulated by clinicians are described. Initial contacts were made with these clinician-technology requestors by the Southwest Research Institute NASA Biomedical Applications Team. The basic purpose of the program was to effectively transfer aerospace technology into functional hardware to solve real biomedical problems.

Laenger, C. J., Sr.

1976-01-01

160

Planetary image conversion task  

NASA Technical Reports Server (NTRS)

The Planetary Image Conversion Task group processed 12,500 magnetic tapes containing raw imaging data from JPL planetary missions and produced an image data base in consistent format on 1200 fully packed 6250-bpi tapes. The output tapes will remain at JPL. A copy of the entire tape set was delivered to US Geological Survey, Flagstaff, Ariz. A secondary task converted computer datalogs, which had been stored in project specific MARK IV File Management System data types and structures, to flat-file, text format that is processable on any modern computer system. The conversion processing took place at JPL's Image Processing Laboratory on an IBM 370-158 with existing software modified slightly to meet the needs of the conversion task. More than 99% of the original digital image data was successfully recovered by the conversion task. However, processing data tapes recorded before 1975 was destructive. This discovery is of critical importance to facilities responsible for maintaining digital archives since normal periodic random sampling techniques would be unlikely to detect this phenomenon, and entire data sets could be wiped out in the act of generating seemingly positive sampling results. Reccomended follow-on activities are also included.

Martin, M. D.; Stanley, C. L.; Laughlin, G.

1985-01-01

161

Task Scheduling in Networks  

Microsoft Academic Search

Scheduling a set of tasks on a set of machines so as to yield an efficient schedule is a basicproblem in computer science and operations research. Most of the research on this problemincorporates the potentially unrealistic assumption that communication between the differentmachines is instantaneous. In this paper we remove this assumption and study the problem ofnetwork scheduling, where each job

Cynthia Phillips Sandia; Nm Clifford Stein

1994-01-01

162

Motor Processes in Simple, Go\\/No-Go, and Choice Reaction Time Tasks: A Psychophysiological Analysis  

Microsoft Academic Search

Psychophysiological measures were used to compare the response preparation and response execution processes of modified versions of F. C. Donders's (1868\\/1969) classic simple, go\\/no-go, and choice reaction time tasks. On all measures, differences between tasks were minimal prior to test stimulus onset, supporting the idea of equivalent motor preparation for the 3 tasks. In addition, the psychophysiological measures indicated that

Jeff O. Miller; Kathy Low

2001-01-01

163

Einstein's equivalence principle in cosmology  

E-print Network

We study physical consequences of the Einstein equivalence principle (EEP) for a Hubble observer in FLRW universe. We introduce the local inertial coordinates with the help of a special conformal transformation. The local inertial metric is Minkowski-flat and materialized by a congruence of time-like geodesics of static observers. The static observers are equipped with the ideal clocks measuring the proper time that is synchronized with the clocks of the Hubble observer. The local inertial metric is used for physical measurements of spacetime intervals with the ideal clocks and rulers. The special conformal transformation preserves null geodesics but does not keep invariant time-like geodesics. Moreover, it makes the rate of the local time coordinate dependent on velocity of the particle which makes impossible to rich the uniform parameterization of the world lines of static observers and light geodesics with a single parameter - they differ by the conformal factor of FLRW metric. It tells us that the metric on the light cone is not Minkowski-flat but depends on the scale factor of FLRW universe and it can be interpreted as a weak violation of EEP for photons. The importance of this violation for gravitational physics is that some of local experiments conducted with freely-propagating electromagnetic waves may be sensitive to the Hubble expansion. We show that the Hubble constant H can be measured within the solar system by means of high-precision spacecraft Doppler tracking as a blue shift of frequency of radio waves circulating in the Earth-spacecraft radio link. We also analyze the behavior of the standing wave in a microwave resonator and show that the standing wave is insensitive to the Hubble expansion.

Sergei M. Kopeikin

2014-02-18

164

Inhomogeneity parameter in designing an ion trap  

E-print Network

In designing an ion trap, geometry and rf source should be optimized such that the trap depth is maximized while the ion remain stable. In a quadrupole linear trap, stable parameters $a$ and $q$ are utilized frequently in describing the stability. However, in a surface trap, the trap have to be mapped to the linear quadrupole trap so that $a$ and $q$ can be evaluated. This work explains how to handle them for surface trap designing and how the geometry and rf source affect it. We conclude that the $q$ parameter should be 0.2~0.22 so that the trap is stable.

Weikang Fan

2014-12-26

165

Pulse radiolysis study on electrons trapped in aqueous solid clathrates  

SciTech Connect

Early concepts on the nature of the 620-nm trapped electron have now been supported by results obtained on clathrates other than tetrabutylammonium (TBA) hydroxide (TBAOH.29H/sub 2/O). In aqueous solid clathrates of trimethylamine, diethylamine, and tert-butylamine, similar e/sub t//sup -//sub (aq)/ transient spectra have been observed. These amines are protonated and OH/sup -/ ions are present in solution which produces a clathrate. In the process of clathrate crystallization from the melt or solution, typical anionic vacancies are created in which some OH/sup -/ ions are missing. Since that ion is a part of the water lattice its absence is equivalent to a vacancy of one water molecule in an aqueous surrounding. This unusual vacancy becomes an aqueous trap for electrons. The same applies to a vacancy of F/sup -/ in tetrabutylammonium fluoride clathrate (TBAF.32H/sub 2/O) which shows identical e/sub t//sup -//sub (aq)/ spectra. Aqueous solid clathrates of acetone and tetrabutylammonium oxalate (neutral pH of liquefied clathrate) do not show the typical high yield, comparatively long-lived e/sub t//sup -//sub (aq)/ spectrum, because there are no traps equivalent to those mentioned above. 25 references, 9 figures.

Zagorski, Z.P.

1986-02-27

166

Three-phase measurements of oil and gas trapping in sand packs  

NASA Astrophysics Data System (ADS)

We measure the trapped saturations of oil and gas as a function of initial saturation in water-wet sand packs. We start with a water-saturated column and inject octane (oil), while water and oil are produced from the bottom. Once water production has ceased, air (gas) then enters from the top, allowing oil and gas to drain under gravity for different times. Finally water is then injected from the bottom to trap both oil and gas. The columns are sliced and the fluids analyzed using gas chromatography. We find that for high initial gas saturations more gas can be trapped in the presence of oil than in a two-phase (gas/water) system. The residual gas saturation can be over 20% compared to 14% in two-phase flow [Al Mansoori SK, Iglauer S, Pentland CH, Bijeljic B, Blunt MJ. Measurements of non-wetting phase trapping applied to carbon dioxide storage. Energy Procedia 2009;1(1):3173-80]. This is unlike previous measurements on consolidated media, where the trapped gas saturation is either similar or lower to that reached in an equivalent two-phase experiment. For lower initial gas saturation, the amount of trapping follows the initial-residual trend seen in two-phase experiments. The amount of oil trapped is insensitive to initial gas saturation or the amount of gas that is trapped, again in contrast to measurements on consolidated media. More oil is trapped than would be predicted from an equivalent two-phase (oil/water) system, although the trapped saturation is never larger than the maximum reached in two-phase flow (around 11%) [Pentland CH, Al Mansoori SK, Iglauer S, Bijeljic B, Blunt MJ. Measurement of non-wetting phase trapping in sand packs. In: SPE 115697, proceedings of the SPE annual technical conference and exhibition, Denver, Colorado, USA; 21-24 September 2008]. These initially surprising results are explained in the context of oil layer stability and the competition between snap-off and piston-like advance. In two-phase systems, displacement is principally by cooperative piston-like advance with relatively little trapping, whereas in consolidated media snap-off is generally more significant. However, oil layer collapse events during three-phase waterflooding rapidly trap the oil which acts as a barrier to direct water/gas displacement, except by snap-off, leading to enhanced gas trapping.

Al Mansoori, Saleh K.; Iglauer, Stefan; Pentland, Christopher H.; Blunt, Martin J.

2009-10-01

167

The trapped human experiment.  

PubMed

This experiment observed the evolution of metabolite plumes from a human trapped in a simulation of a collapsed building. Ten participants took it in turns over five days to lie in a simulation of a collapsed building and eight of them completed the 6 h protocol while their breath, sweat and skin metabolites were passed through a simulation of a collapsed glass-clad reinforced-concrete building. Safety, welfare and environmental parameters were monitored continuously, and active adsorbent sampling for thermal desorption GC-MS, on-line and embedded CO, CO(2) and O(2) monitoring, aspirating ion mobility spectrometry with integrated semiconductor gas sensors, direct injection GC-ion mobility spectrometry, active sampling thermal desorption GC-differential mobility spectrometry and a prototype remote early detection system for survivor location were used to monitor the evolution of the metabolite plumes that were generated. Oxygen levels within the void simulator were allowed to fall no lower than 19.1% (v). Concurrent levels of carbon dioxide built up to an average level of 1.6% (v) in the breathing zone of the participants. Temperature, humidity, carbon dioxide levels and the physiological measurements were consistent with a reproducible methodology that enabled the metabolite plumes to be sampled and characterized from the different parts of the experiment. Welfare and safety data were satisfactory with pulse rates, blood pressures and oxygenation, all within levels consistent with healthy adults. Up to 12 in-test welfare assessments per participant and a six-week follow-up Stanford Acute Stress Response Questionnaire indicated that the researchers and participants did not experience any adverse effects from their involvement in the study. Preliminary observations confirmed that CO(2), NH(3) and acetone were effective markers for trapped humans, although interactions with water absorbed in building debris needed further study. An unexpected observation from the NH(3) channel was the suppression of NH(3) during those periods when the participants slept, and this will be the subject of further study, as will be the detailed analysis of the casualty detection data obtained from the seven instruments used. PMID:21908906

Huo, R; Agapiou, A; Bocos-Bintintan, V; Brown, L J; Burns, C; Creaser, C S; Devenport, N A; Gao-Lau, B; Guallar-Hoyas, C; Hildebrand, L; Malkar, A; Martin, H J; Moll, V H; Patel, P; Ratiu, A; Reynolds, J C; Sielemann, S; Slodzynski, R; Statheropoulos, M; Turner, M A; Vautz, W; Wright, V E; Thomas, C L P

2011-12-01

168

Task switching in a hierarchical task structure: evidence for the fragility of the task repetition benefit  

NASA Technical Reports Server (NTRS)

This study examined how task switching is affected by hierarchical task organization. Traditional task-switching studies, which use a constant temporal and spatial distance between each task element (defined as a stimulus requiring a response), promote a flat task structure. Using this approach, Experiment 1 revealed a large switch cost of 238 ms. In Experiments 2-5, adjacent task elements were grouped temporally and/or spatially (forming an ensemble) to create a hierarchical task organization. Results indicate that the effect of switching at the ensemble level dominated the effect of switching at the element level. Experiments 6 and 7, using an ensemble of 3 task elements, revealed that the element-level switch cost was virtually absent between ensembles but was large within an ensemble. The authors conclude that the element-level task repetition benefit is fragile and can be eliminated in a hierarchical task organization.

Lien, Mei-Ching; Ruthruff, Eric

2004-01-01

169

Collisional trap losses of cold, magnetically-trapped Br atoms  

E-print Network

Near-threshold photodissociation of Br$_2$ from a supersonic beam produces slow bromine atoms that are trapped in the magnetic field minimum formed between two opposing permanent magnets. Here, we quantify the dominant trap loss rate due to collisions with two sources of residual gas: the background limited by the vacuum chamber base pressure, and the carrier gas during the supersonic gas pulse. The loss rate due to collisions with residual Ar in the background follows pseudo first-order kinetics, and the bimolecular rate coefficient for collisional loss from the trap is determined by measurement of this rate as a function of the background Ar pressure. This rate coefficient is smaller than the total elastic collision rate coefficient, as it only samples those collisions that lead to trap loss, and is determined to be $\\langle\

Lam, J; Softley, T P

2014-01-01

170

46 CFR 110.20-1 - Equivalents.  

Code of Federal Regulations, 2010 CFR

...DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING GENERAL PROVISIONS Equivalents § 110.20-1...necessary, the Marine Safety Center may require engineering evaluations and tests to demonstrate the...

2010-10-01

171

46 CFR 110.20-1 - Equivalents.  

...DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING GENERAL PROVISIONS Equivalents § 110.20-1...necessary, the Marine Safety Center may require engineering evaluations and tests to demonstrate the...

2014-10-01

172

46 CFR 110.20-1 - Equivalents.  

Code of Federal Regulations, 2013 CFR

...DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING GENERAL PROVISIONS Equivalents § 110.20-1...necessary, the Marine Safety Center may require engineering evaluations and tests to demonstrate the...

2013-10-01

173

46 CFR 110.20-1 - Equivalents.  

Code of Federal Regulations, 2011 CFR

...DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING GENERAL PROVISIONS Equivalents § 110.20-1...necessary, the Marine Safety Center may require engineering evaluations and tests to demonstrate the...

2011-10-01

174

46 CFR 110.20-1 - Equivalents.  

Code of Federal Regulations, 2012 CFR

...DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING GENERAL PROVISIONS Equivalents § 110.20-1...necessary, the Marine Safety Center may require engineering evaluations and tests to demonstrate the...

2012-10-01

175

Nontarget Captures (luring Small Mammal Trapping with Snap Traps  

Microsoft Academic Search

There is little published information available on non-target captures during small mammal trapping. We used a variety of snap traps baited with a rolled oat-peanut butter mix to capture 2,054 individuals from 9 genera of small mammals in a study of small mammal and avian community structure in riparian areas and adjacent loblolly pine (Pinus taeda) plantations. We also captured

David G. Peitz; Philip A. Tappe; Ronald E. Thill; Roger W. Perry; M. Anthony Melchiors; T. Bentiy Wigley

2001-01-01

176

Trapping low-energy antiprotons in an ion trap  

SciTech Connect

A fraction of antiprotons from the Low Energy Antiproton Ring (LEAR) of CERN are slowed from 5.9 MeV to below 3 keV as they pass through thin foils. Transmitted particle energy distribution and low energy antiproton yield are measured by a time-of-flight technique. The difference in the range of protons and antiprotons (known as the Barkas effect) is observed. While still in flight, up to 1.3 {times} 10{sup 5} antiprotons with energies between 0 eV to 3 keV are stored in an ion trap from a single pulse of 5.9 MeV antiprotons leaving LEAR, thus a trapping efficiency exceeding of 4 {times} 10{sup {minus}4} is established. Trapped antiprotons maintain their initial energy distribution unless allowed to collide with a cloud of trapped electrons, whereupon they slow and cool below 1 meV in 10 s, and fall into a harmonic potential well suited for precision mass measurements. The slowing, trapping and cooling of antiprotons are the main focus of this thesis. The stored antiprotons are in thermal equilibrium at 4.2 K. In this ion trap, the antiproton cyclotron frequency is measured and compared with the proton (or electron) cyclotron frequency. The new measured ratio of the antiproton and proton inertial masses, with its 4 {times} 10{sup {minus}8} uncertainty, is more than three orders of magnitude more accurate than previous measurements using exotic atoms. This is a most precise test of CPT invariance with baryons. The antiproton lifetime in an ion trap was measured to be more than 103 days by trapping a cloud of antiprotons for 59 days. The indicates the number density of atoms is less than 100/cm{sup 3} which corresponds to the pressure in the vacuum chamber being less than 5 {times} 10{sup {minus}17} Torr at 4.2 K if we apply the ideal gas law.

Fei, Xiang.

1990-01-01

177

Task-specific effects of reward on task switching.  

PubMed

Although cognitive control and reinforcement learning have been researched extensively over the last few decades, only recently have studies investigated their interrelationship. An important unanswered question concerns how the control system decides what task to execute and how vigorously to carry out the task once selected. Based on a recent theory of control formulated according to principles of hierarchical reinforcement learning, we asked whether rewards can affect top-down control over task performance at the level of task representation. Participants were rewarded for correctly performing only one of two tasks in a standard task-switching experiment. Reaction times and error rates were lower for the reinforced task compared to the non-reinforced task. Moreover, the switch cost in error rates for the non-reinforced task was significantly larger compared to the reinforced task, especially for trials in which the imperative stimulus afforded different responses for the two tasks, resulting in a "non-paradoxical" asymmetric switch cost. These findings suggest that reinforcement at the task level resulted in greater application of top-down control rather than in stronger stimulus-response pathways for the rewarded task. PMID:24984832

Umemoto, Akina; Holroyd, Clay B

2014-07-01

178

Trapped Quintessential Inflation  

E-print Network

Quintessential inflation is studied using a string modulus as the inflaton - quintessence field. The modulus begins its evolution at the steep part of its scalar potential, which is due to non-perturbative effects (e.g. gaugino condensation). It is assumed that the modulus crosses an enhanced symmetry point (ESP) in field space. Particle production at the ESP temporarily traps the modulus resulting in a brief period of inflation. More inflation follows, due to the flatness of the potential, since the ESP generates either an extremum (maximum or minimum) or a flat inflection point in the scalar potential. Eventually, the potential becomes steep again and inflation is terminated. After reheating the modulus freezes due to cosmological friction at a large value, such that its scalar potential is dominated by contributions due to fluxes in the extra dimensions or other effects. The modulus remains frozen until the present, when it can become quintessence and account for the dark energy necessary to explain the observed accelerated expansion.

J. C. Bueno Sanchez; K. Dimopoulos

2006-05-26

179

Solar Thermal Task Analysis  

NSDL National Science Digital Library

The Advanced Technology Environmental and Energy Center (ATEEC) has provided this document which includes an overview of objectives and task analysis for individuals installing solar water and pool heating systems. Areas of expertise include working safely with solar hot water and pool heating systems, identifying systems and their components and installing equipment. Users must download this resource for viewing, which requires a free log-in. There is no cost to download the item.

180

Small Wind Task Analysis  

NSDL National Science Digital Library

The Advanced Technology Environmental and Energy Center (ATEEC) has compiled this document which lists objectives and task analysis for small wind energy system installers. The document is divided into areas including of competencies such as conducting a wind energy site assessment, working safely with small wind energy systems and performing system checkouts and inspection. Users must download this resource for viewing, which requires a free log-in. There is no cost to download the item.

181

Ultra-thin, light-trapping silicon solar cells  

NASA Technical Reports Server (NTRS)

Design concepts for ultra-thin (2 to 10 microns) high efficiency single-crystal silicon cells are discussed. Light trapping allows more light to be absorbed at a given thickness, or allows thinner cells of a given Jsc. Extremely thin cells require low surface recombination velocity at both surfaces, including the ohmic contacts. Reduction of surface recombination by growth of heterojunctions of ZnS and GaP on Si has been demonstrated. The effects of these improvements on AM0 efficiency is shown. The peak efficiency increases, and the optimum thickness decreases. Cells under 10 microns thickness can retain almost optimum power. The increase of absorptance due to light trapping is considered. This is not a problem if the light-trapping cells are sufficiently thin. Ultra-thin cells have high radiation tolerance. A 2 microns thick light-trapping cell remains over 18 percent efficient after the equivalent of 20 years in geosynchronous orbit. Including a 50 microns thick coverglass, the thin cells had specific power after irradiation over ten times higher than the baseline design.

Landis, Geoffrey A.

1989-01-01

182

Interstitial diffusion in systems with multiple sorts of traps  

NASA Astrophysics Data System (ADS)

The role of several sorts of traps for one diffusing interstitial component is investigated. The site fraction of this component in each trap is calculated due to the local thermodynamic equilibrium condition with its site fraction in the lattice. Combining Fick's first law for diffusive fluxes of individual site fractions with the equilibrium condition and the mass balance allows deriving an extended nonlinear diffusion equation. If the molar volumes of the trap positions are constant with respect to time, then a generalized chemical diffusion coefficient can be derived, which allows performing the diffusion study in terms of the total concentration of the interstitial component. As an alternative way, the total diffusion flux can also be treated as the sum of diffusion fluxes of individual fractions combined with local redistribution of individual fractions based on the thermodynamic local equilibrium condition. Both concepts are presented in simulations for the diffusion of hydrogen in the system with traps as immobile dislocations, substitutional impurities and interfaces of incoherent carbide nanoprecipitates. Both concepts provide equivalent results and exhibit an asymmetric behaviour with respect to a charging/discharging process.

Fischer, F. D.; Svoboda, J.; Kozeschnik, E.

2013-03-01

183

Mini ion trap mass spectrometer  

DOEpatents

An ion trap which operates in the regime between research ion traps which can detect ions with a mass resolution of better than 1:10.sup.9 and commercial mass spectrometers requiring 10.sup.4 ions with resolutions of a few hundred. The power consumption is kept to a minimum by the use of permanent magnets and a novel electron gun design. By Fourier analyzing the ion cyclotron resonance signals induced in the trap electrodes, a complete mass spectra in a single combined structure can be detected. An attribute of the ion trap mass spectrometer is that overall system size is drastically reduced due to combining a unique electron source and mass analyzer/detector in a single device. This enables portable low power mass spectrometers for the detection of environmental pollutants or illicit substances, as well as sensors for on board diagnostics to monitor engine performance or for active feedback in any process involving exhausting waste products.

Dietrich, Daniel D. (Livermore, CA); Keville, Robert F. (Valley Springs, CA)

1995-01-01

184

Mini ion trap mass spectrometer  

DOEpatents

An ion trap is described which operates in the regime between research ion traps which can detect ions with a mass resolution of better than 1:10{sup 9} and commercial mass spectrometers requiring 10{sup 4} ions with resolutions of a few hundred. The power consumption is kept to a minimum by the use of permanent magnets and a novel electron gun design. By Fourier analyzing the ion cyclotron resonance signals induced in the trap electrodes, a complete mass spectra in a single combined structure can be detected. An attribute of the ion trap mass spectrometer is that overall system size is drastically reduced due to combining a unique electron source and mass analyzer/detector in a single device. This enables portable low power mass spectrometers for the detection of environmental pollutants or illicit substances, as well as sensors for on board diagnostics to monitor engine performance or for active feedback in any process involving exhausting waste products. 10 figs.

Dietrich, D.D.; Keville, R.F.

1995-09-19

185

Gated charged-particle trap  

DOEpatents

The design and operation of a new type of charged-particle trap provides simultaneous measurements of mass, charge, and velocity of large electrospray ions. The trap consists of a detector tube mounted between two sets of center-bored trapping plates. Voltages applied to the trapping plates define symmetrically-opposing potential valleys which guide axially-injected ions to cycle back and forth through the charge-detection tube. A low noise charge-sensitive amplifier, connected to the tube, reproduces the image charge of individual ions as they pass through the detector tube. Ion mass is calculated from measurement of ion charge and velocity following each passage through the detector. 5 figs.

Benner, W.H.

1999-03-09

186

Vortex dynamics in anisotropic traps  

SciTech Connect

We investigate the dynamics of linear vortex lattices in anisotropic traps in two dimensions and show that the interplay between the rotation and the anisotropy leads to a rich but highly regular dynamics.

McEndoo, S.; Busch, Th. [Department of Physics, University College Cork, Cork (Ireland)

2010-07-15

187

Backward Blocking and Interference between Cues Are Empirically Equivalent in Non-Causally Framed Learning Tasks  

ERIC Educational Resources Information Center

Backward blocking (BB) and interference between cues (IbC) are cue competition effects produced by very similar manipulations. In a standard BB design, both effects might occur simultaneously, which implies a potential problem for studying BB. In the present study with humans, the magnitude of both effects was compared using a non-causal scenario…

Luque, David; Moris, Joaquin; Orgaz, Cristina; Cobos, Pedro L.; Matute, Helena

2011-01-01

188

Learner Mining of Pre-Task and Task Input  

ERIC Educational Resources Information Center

The findings reported in this article suggest that learners inevitably "mine" wordings contained in pre-task and task materials when performing tasks, even when the teacher did not explicitly draw learner attention to these features. However, this was found to be true only with written materials, and learners did not appear to mine specific…

Boston, Jeremy Scott

2008-01-01

189

Electron-beam ion trap  

SciTech Connect

Production of a very highly charged ion is extremely difficult, requiring successive collisions having center-of-mass energies greater than the binding energies of the electrons to be removed. One can achieve such collisions either by directing a relativistic heavy-ion beam from a large accelerator into a stationary foil target or by directing an electron beam a thousandfold less energetic into a stationary ion target. The latter method is used in the electron-beam ion trap. Our ability today to produce hydrogen-like ions of uranium or any other element in an electron-beam ion trap is the result of several innovations made by different investigators over a long period of time. The use of ion cooling and a recent increase in the electron-beam energy finally enable the production and trapping of any ion up to bare uranium. Now there is also a vigorous effort to use the electron-beam ion trap as a source of these ions for external experiments. Although the electron-beam ion trap was initially developed for x-ray measurements of trapped ions, one can change its mode of operation to provide an efficient source of very slow, very highly charged ions. 17 refs., 7 figs.

Marrs, R.E.; Beiersdorfer, P.; Schneider, D. (Lawrence Livermore National Lab., CA (United States))

1994-10-01

190

Energy Conservation Project Evaluation by Investment Equivalents  

E-print Network

of capital which can be spent to save a unit of energy and still meet the criteria for profitability.' 'Investment Equivalents' can be calculated easily for any form of energy, at any location. The 'Investment Equivalent' can be used to screen energy saving...

Larson, R. J.

1984-01-01

191

Remarks on statistical errors in equivalent widths  

E-print Network

Equivalent width measurements for rapid line variability in atomic spectral lines are degraded by increasing error bars with shorter exposure times. We derive an expression for the error of the line equivalent width $\\sigma(W_\\lambda)$ with respect to pure photon noise statistics and provide a correction value for previous calculations.

Klaus Vollmann; Thomas Eversberg

2006-07-03

192

Innovation: the classic traps.  

PubMed

Never a fad, but always in or out of fashion, innovation gets rediscovered as a growth enabler every half dozen years. Too often, though, grand declarations about innovation are followed by mediocre execution that produces anemic results, and innovation groups are quietly disbanded in cost-cutting drives. Each managerial generation embarks on the same enthusiastic quest for the next new thing. And each generation faces the same vexing challenges- most of which stem from the tensions between protecting existing revenue streams critical to current success and supporting new concepts that may be crucial to future success. In this article, Harvard Business School professor Rosabeth Moss Kanter reflects on the four major waves of innovation enthusiasm she's observed over the past 25 years. She describes the classic mistakes companies make in innovation strategy, process, structure, and skills assessment, illustrating her points with a plethora of real-world examples--including AT&T Worldnet, Timberland, and Ocean Spray. A typical strategic blunder is when managers set their hurdles too high or limit the scope of their innovation efforts. Quaker Oats, for instance, was so busy in the 1990s making minor tweaks to its product formulas that it missed larger opportunities in distribution. A common process mistake is when managers strangle innovation efforts with the same rigid planning, budgeting, and reviewing approaches they use in their existing businesses--thereby discouraging people from adapting as circumstances warrant. Companies must be careful how they structure fledgling entities alongside existing ones, Kanter says, to avoid a clash of cultures and agendas--which Arrow Electronics experienced in its attempts to create an online venture. Finally, companies commonly undervalue and underinvest in the human side of innovation--for instance, promoting individuals out of innovation teams long before their efforts can pay off. Kanter offers practical advice for avoiding these traps. PMID:17131564

Kanter, Rosabeth Moss

2006-11-01

193

Method for the prediction of the effective dose equivalent to the crew of the International Space Station  

NASA Astrophysics Data System (ADS)

This paper describes a methodology for assessing the pre-mission exposure of space crew aboard the International Space Station (ISS) in terms of an effective dose equivalent. In this approach, the PHITS Monte Carlo code was used to assess the particle transport of galactic cosmic radiation (GCR) and trapped radiation for solar maximum and minimum conditions through an aluminum shield thickness. From these predicted spectra, and using fluence-to-dose conversion factors, a scaling ratio of the effective dose equivalent rate to the ICRU ambient dose equivalent rate at a 10 mm depth was determined. Only contributions from secondary neutrons, protons, and alpha particles were considered in this analysis. Measurements made with a tissue equivalent proportional counter (TEPC) located at Service Module panel 327, as captured through a semi-empirical correlation in the ISSCREM code, where then scaled using this conversion factor for prediction of the effective dose equivalent. This analysis shows that at this location within the service module, the total effective dose equivalent is 10-30% less than the total TEPC dose equivalent. Approximately 75-85% of the effective dose equivalent is derived from the GCR. This methodology provides an opportunity for pre-flight predictions of the effective dose equivalent and therefore offers a means to assess the health risks of radiation exposure on ISS flight crew.

El-Jaby, Samy; Tomi, Leena; Sihver, Lembit; Sato, Tatsuhiko; Richardson, Richard B.; Lewis, Brent J.

2014-03-01

194

4.NF Explaining Fraction Equivalence with Pictures  

NSDL National Science Digital Library

This is a task from the Illustrative Mathematics website that is one part of a complete illustration of the standard to which it is aligned. Each task has at least one solution and some commentary that addresses important asects of the task and its potential use. Here are the first few lines of the commentary for this task: The rectangle below has length 1. What fraction does the shaded part represent? The rectangle below has the same length as the rectangle above. What fr...

195

All steam traps are not equal  

Microsoft Academic Search

Proper selection of a steam trap will result in a long-lasting, trouble-free steam distribution system. The definition of a trap is simple enough: it should get rid of air and purge off noncondensibles when the system is started up and drain condensate anytime during operation. This is the reason traps are sometimes called automatic drain valves. A steam trap should

Alesson

1995-01-01

196

Collisional trap losses of cold magnetically trapped Br atoms  

NASA Astrophysics Data System (ADS)

Near-threshold photodissociation of Br2 from a supersonic beam produces slow bromine atoms that are trapped in the magnetic-field minimum formed between two opposing permanent magnets. Here we quantify the dominant trap-loss rate due to collisions with two sources of residual gas: the background limited by the vacuum chamber base pressure and the carrier gas during the supersonic gas pulse. The loss rate due to collisions with residual Ar in the background follows pseudo-first-order kinetics and the bimolecular rate coefficient for collisional loss from the trap is determined by measurement of this rate as a function of the background Ar pressure. This rate coefficient is smaller than the total elastic collision rate coefficient, as it only samples those collisions that lead to trap loss, and is determined to be =(1.12 ±0.09 ) ×10-9cm3s-1 . The calculated differential cross section can be used with this value to estimate a trap depth of 293 ±24 mK . Carrier-gas collisions occur only during the tail of the supersonic beam pulse. Using the differential cross section verified by the background-gas collision measurements provides an estimate of the peak molecular-beam density of (3.0 ±0.3 ) ×1013cm-3 , in good agreement with the prediction of a simple supersonic expansion model. Finally, we estimate the trap-loss rate due to Majorana transitions to be negligible, owing to the relatively large trapped-atom phase-space volume.

Lam, J.; Rennick, C. J.; Softley, T. P.

2014-12-01

197

Equivalence in Ventilation and Indoor Air Quality  

SciTech Connect

We ventilate buildings to provide acceptable indoor air quality (IAQ). Ventilation standards (such as American Society of Heating, Refrigerating, and Air-Conditioning Enginners [ASHRAE] Standard 62) specify minimum ventilation rates without taking into account the impact of those rates on IAQ. Innovative ventilation management is often a desirable element of reducing energy consumption or improving IAQ or comfort. Variable ventilation is one innovative strategy. To use variable ventilation in a way that meets standards, it is necessary to have a method for determining equivalence in terms of either ventilation or indoor air quality. This study develops methods to calculate either equivalent ventilation or equivalent IAQ. We demonstrate that equivalent ventilation can be used as the basis for dynamic ventilation control, reducing peak load and infiltration of outdoor contaminants. We also show that equivalent IAQ could allow some contaminants to exceed current standards if other contaminants are more stringently controlled.

Sherman, Max; Walker, Iain; Logue, Jennifer

2011-08-01

198

Universal collisional activation ion trap mass spectrometry  

DOEpatents

A universal collisional activation ion trap comprises an ion trapping means containing a bath gas and having connected thereto a noise signal generator. A method of operating a universal collisional activation ion trap comprises the steps of: providing an ion trapping means; introducing into the ion trapping means a bath gas; and, generating a noise signal within the ion trapping means; introducing into the ion trapping means a substance that, when acted upon by the noise signal, undergoes collisional activation to form product ions.

McLuckey, S.A.; Goeringer, D.E.; Glish, G.L.

1993-04-27

199

Effect of bait in live trapping Peromyscus  

USGS Publications Warehouse

SUMMARY: Evidence from live trapping tests indicated that Peromyscus leucopus did not leave their home ranges because of the attraction of trap bait in nearby areas. A trap line down the center of a heavily live-trapped area caught as many mice before the area trapping as afterward. Thus, there was reason to believe that the area trapping did not serve to pre-bait the mice. Two unbaited lines of live traps caught an equal number of Peromyscus. When one line was baited with rolled oats and peanut butter the efficiency of the traps was improved to the extent that the baited line captured more than twice as many mice as the unbaited line. It is concluded that for the species and habitat tested it is safe to make population calculations based on the assumption that the animals remain within their home ranges and do not tend to move into the trapped area because of the attraction of the trap bait.

Stickel, L.F.

1948-01-01

200

Maximally Expressive Task Modeling  

NASA Technical Reports Server (NTRS)

Planning and scheduling systems organize "tasks" into a timeline or schedule. The tasks are defined within the scheduling system in logical containers called models. The dictionary might define a model of this type as "a system of things and relations satisfying a set of rules that, when applied to the things and relations, produce certainty about the tasks that are being modeled." One challenging domain for a planning and scheduling system is the operation of on-board experiment activities for the Space Station. The equipment used in these experiments is some of the most complex hardware ever developed by mankind, the information sought by these experiments is at the cutting edge of scientific endeavor, and the procedures for executing the experiments are intricate and exacting. Scheduling is made more difficult by a scarcity of space station resources. The models to be fed into the scheduler must describe both the complexity of the experiments and procedures (to ensure a valid schedule) and the flexibilities of the procedures and the equipment (to effectively utilize available resources). Clearly, scheduling space station experiment operations calls for a "maximally expressive" modeling schema. Modeling even the simplest of activities cannot be automated; no sensor can be attached to a piece of equipment that can discern how to use that piece of equipment; no camera can quantify how to operate a piece of equipment. Modeling is a human enterprise-both an art and a science. The modeling schema should allow the models to flow from the keyboard of the user as easily as works of literature flowed from the pen of Shakespeare. The Ground Systems Department at the Marshall Space Flight Center has embarked on an effort to develop a new scheduling engine that is highlighted by a maximally expressive modeling schema. This schema, presented in this paper, is a synergy of technological advances and domain-specific innovations.

Japp, John; Davis, Elizabeth; Maxwell, Theresa G. (Technical Monitor)

2002-01-01

201

Impurity color centers in quartz and trapped electron dating - Electron spin resonance, thermoluminescence studies.  

NASA Technical Reports Server (NTRS)

Investigation of impurity-related electron-hole traps that are known to be sensitive to ionizing radiations. Electron spin resonance (ESR) equivalent natural doses were determined for the Al hole trap in virgin specimens; the doses agreed with estimates based on published data for the Ge electron trap. The 0.17 deg/sec 180 and 300 C thermoluminescence (TL) peaks in natural specimens were found to have activation energies approximately correct for the Ge trap. The 300 C peak was also found to be correlated with annealing of the Ge electron resonance in gamma-irradiated, step-annealed specimens. Although the 300 C peak occurs in virgin specimens, the corresponding natural Ge electron resonance was not observed.

Mcmorris, D. W.

1971-01-01

202

Task-Based Information Searching.  

ERIC Educational Resources Information Center

Reviews studies on the relationship between task performance and information searching by end-users, focusing on information searching in electronic environments and information retrieval systems. Topics include task analysis; task characteristics; search goals; modeling information searching; modeling search goals; information seeking behavior;…

Vakkari, Pertti

2003-01-01

203

Stem Cell Task Force  

NSDL National Science Digital Library

This Web site from the National Institutes of Health (NIH) provides an overview of the activities of an NIH task force established to move the stem cell research agenda forward. The section titled Scientific Research may be of particular interest to researchers in this area. It provides links to the Web sites of stem cell-related research at a number of NIH institutes, as well as an extensive information index, a FAQs page about stem cell research, information on funding opportunities, and much more.

204

Trapping, self-trapping and the polaron family  

NASA Astrophysics Data System (ADS)

The earliest ideas of the polaron recognized that the coupling of an electron to ionic vibrations would affect its apparent mass and could effectively immobilize the carrier (self-trapping). We discuss how these basic ideas have been generalized to recognize new materials and new phenomena. First, there is an interplay between self-trapping and trapping associated with defects or with fluctuations in an amorphous solid. In high dielectric constant oxides, like HfO2, this leads to oxygen vacancies having as many as five charge states. In colossal magnetoresistance manganites, this interplay makes possible the scanning tunnelling microscopy (STM) observation of polarons. Second, excitons can self-trap and, by doing so, localize energy in ways that can modify the material properties. Third, new materials introduce new features, with polaron-related ideas emerging for uranium dioxide, gate dielectric oxides, Jahn-Teller systems, semiconducting polymers and biological systems. The phonon modes that initiate self-trapping can be quite different from the longitudinal optic modes usually assumed to dominate. Fourth, there are new phenomena, like possible magnetism in simple oxides, or with the evolution of short-lived polarons, like muons or excitons. The central idea remains that of a particle whose properties are modified by polarizing or deforming its host solid, sometimes profoundly. However, some of the simpler standard assumptions can give a limited, indeed misleading, description of real systems, with qualitative inconsistencies. We discuss representative cases for which theory and experiment can be compared in detail.

Stoneham, A. M.; Gavartin, J.; Shluger, A. L.; Kimmel, A. V.; Muñoz Ramo, D.; Rønnow, H. M.; Aeppli, G.; Renner, C.

2007-06-01

205

Control equivalent turbulence input model for the UH-60 helicopter  

NASA Astrophysics Data System (ADS)

Flight test data from a UH-60 Black Hawk helicopter hovering in the atmospheric turbulence downwind of a large cube-shaped hanger on a wind day were collected. An inverse modeling method was used to extract the control inputs that are required to replicate the portion of the aircraft response attributable to atmospheric disturbances from the flight-test data. Based on the extracted control inputs, a parametric Control Equivalent Turbulence Input (CETI) model comprised of white-noise driven filters that have a Dryden-type form and are scalable for varying levels of turbulence were developed. The outputs of the filters are disturbance time histories that sum with the pilot's inputs, to replicate the effects of atmospheric turbulence in calm atmospheric conditions. A ground-based piloted simulation study was conducted in the NASA/Ames Vertical Motion Simulator (VMS) comparing the empirically based CETI model with flight-test data and with a complex Simulation Of Rotor Blade Element Turbulence (SORBET) model. Two test pilots performed precision hover tasks with increasing levels of simulated turbulence from both the CETI and SORBET models. The results of the simulation study showed good pilot acceptance of the CETI model and provided a good level of validation of the more complex rotating frame turbulence model. An in-flight simulation study was conducted on the Rotorcraft Aircrew Systems Concepts Airborne Laboratory (RASCAL) UH-60 helicopter using the CETI model. Two test pilots performed a precision hover task on calm days with simulated CETI turbulence. Aircraft response metrics showed good agreement between a hover task with CETI simulated turbulence and the same task in atmospheric turbulence. Both pilots commented that the RASCAL's response to CETI turbulence was similar to the response hovering downwind of the large cube-shaped hangar on a windy day. The CETI model developed in this dissertation simulates turbulence by generating equivalent disturbance inputs to the control system of the helicopter. This makes the CETI model suitable for use with any helicopter math model to study the effects of turbulence on handling qualities and for use in designing control systems to reject atmospheric turbulence.

Lusardi, Jeff

206

Atomic Oxygen Task  

NASA Technical Reports Server (NTRS)

This report details work performed by the Center for Applied Optics (CAO) at the University of Alabama in Huntsville (UAH) on the contract entitled 'Atomic Oxygen Task' for NASA's Marshall Space Flight Center (contract NAS8-38609, Delivery Order 109, modification number 1). Atomic oxygen effects on exposed materials remain a critical concern in designing spacecraft to withstand exposure in the Low Earth Orbit (LEO) environment. The basic objective of atomic oxygen research in NASA's Materials & Processes (M&P) Laboratory is to provide the solutions to material problems facing present and future space missions. The objective of this work was to provide the necessary research for the design of specialized experimental test configurations and development of techniques for evaluating in-situ space environmental effects, including the effects of atomic oxygen and electromagnetic radiation on candidate materials. Specific tasks were performed to address materials issues concerning accelerated environmental testing as well as specifically addressing materials issues of particular concern for LDEF analysis and Space Station materials selection.

Hadaway, James B.

1997-01-01

207

Thévenin equivalence in disorderless quantum networks  

NASA Astrophysics Data System (ADS)

We outline the procedure of extending the Thévenin equivalence principle for classical electric circuits to reducing Aharonov-Bohm-based quantum networks into equivalent models. With examples, we show from first principles how the requirements are related to the electron band structure's Fermi level and the lattice spacing of the network. Quantum networks of varying degrees of coupling strength from four basic classifications of single and double entangled loops sharing symmetry and highly correlated band structures are used to demonstrate the concept. We show the limitations of how the principle may be applied. Several classes of examples are given and their equivalent forms are shown.

Cain, C. A.; Wu, C. H.

2015-01-01

208

Use of a linear Paul trap to study random noise-induced beam degradation in high-intensity accelerators.  

PubMed

A random noise-induced beam degradation that can affect intense beam transport over long propagation distances has been experimentally studied by making use of the transverse beam dynamics equivalence between an alternating-gradient (AG) focusing system and a linear Paul trap system. For the present studies, machine imperfections in the quadrupole focusing lattice are considered, which are emulated by adding small random noise on the voltage waveform of the quadrupole electrodes in the Paul trap. It is observed that externally driven noise continuously produces a nonthermal tail of trapped ions, and increases the transverse emittance almost linearly with the duration of the noise. PMID:19392447

Chung, Moses; Gilson, Erik P; Davidson, Ronald C; Efthimion, Philip C; Majeski, Richard

2009-04-10

209

Abel ODEs: Equivalence and Integrable Classes  

E-print Network

differential equations of Abel type; Equivalence; Integrab* *le classes; Symbolic computation differential equations (ODEs), equival* *ence problem, inte- grable cases, symbolic computation. Nature differential equations, and use it to return a closed form solution without requiring furthe* *r

Waterloo, University of

210

The Economist Interactive: Equivalent Country Comparisons  

NSDL National Science Digital Library

This interactive tools allows the user to learn which countries parallel the states, provinces or territories of the United States, China, India and Brazil and  presents country equivalent data for both GDP and population.

211

Distinguishing Provenance Equivalence of Earth Science Data  

NASA Technical Reports Server (NTRS)

Reproducibility of scientific research relies on accurate and precise citation of data and the provenance of that data. Earth science data are often the result of applying complex data transformation and analysis workflows to vast quantities of data. Provenance information of data processing is used for a variety of purposes, including understanding the process and auditing as well as reproducibility. Certain provenance information is essential for producing scientifically equivalent data. Capturing and representing that provenance information and assigning identifiers suitable for precisely distinguishing data granules and datasets is needed for accurate comparisons. This paper discusses scientific equivalence and essential provenance for scientific reproducibility. We use the example of an operational earth science data processing system to illustrate the application of the technique of cascading digital signatures or hash chains to precisely identify sets of granules and as provenance equivalence identifiers to distinguish data made in an an equivalent manner.

Tilmes, Curt; Yesha, Ye; Halem, M.

2010-01-01

212

Snow water equivalent estimation using blackbox optimization  

E-print Network

Feb 23, 2011 ... and ablation model that infers the SWE variation from temperature and precipitation data [12]. ... passive microwave data (SSM/I sensors). ...... Estimating the uncertainty in spatial estimates of areal snow water equivalent.

Alarie et al.

2011-02-23

213

Positron trapping at grain boundaries  

SciTech Connect

The standard positron trapping model has often been applied, as a simple approximation, to the interpretation of positron lifetime spectra in situations of diffusion-controlled trapping. This paper shows that this approximation is not sufficiently accurate, and presents a model based on the correct solution of the diffusion equation, in the version appropriate for studying positron trapping at grain boundaries. The model is used for the analysis of new experimental data on positron lifetime spectra in a fine-grained Al-Ca-Zn alloy. Previous results on similar systems are also discussed and reinterpreted. The analysis yields effective diffusion coefficients not far from the values known for the base metals of the alloys.

Dupasquier, A. (Dipartimento di Fisica del Politecnico di Milano, Piazza Leonardo da Vinci 32, I-20133 Milano (Italy)); Romero, R.; Somoza, A. (Instituto de Fisica de Materiales Tandil, Facultad de Ciencias Exactas, Universidad Nacional del Centro de la Provincia de Buenos Aires, Pinto 399, 7000 Tandil (Argentina))

1993-10-01

214

Scenario-Based Tasks  

NSDL National Science Digital Library

This page from The Experiential Learning Center provides a number of scenario-based tasks for use in the classroom or for professional development training. The materials are freely available for download and use and would be applicable to learners in a variety of subjects including software development, faculty professional development, office system applications/ICT, biology/bioinformatics, environmental studies, Python programming, engineering, network security/MIS, computational thinking and English writing. Instructor guides and other classroom instructional materials are provided. The project requests that educators let them know when these materials are used in order to track dissemination of the work and in order to inform the community about upcoming workshops and presentations.

2012-10-09

215

Financial Action Task Force  

NSDL National Science Digital Library

Created in 1989, the Financial Action Task Force (FATF) is an inter-governmental body whose purpose is "the development and promotion of national and international policies to combat money laundering and terrorist financing." Users who are new to the site can get started quickly by looking over the "Quick Links" section on the right-hand side of the homepage. Here they will find a handbook that details how the FATF creates its profiles, information on the methodology, and primary recommendations for creating a coherent set of counter-measures against money laundering. Also, the site includes a "Publications" area, which contains short summaries of reports, along with annual reports dating from 1990 and newsletters from 2007. Finally, the site also contains a listing of recent news items and upcoming events and conferences sponsored by the FATF.

216

Dark matter and the equivalence principle  

NASA Technical Reports Server (NTRS)

A survey is presented of the current understanding of dark matter invoked by astrophysical theory and cosmology. Einstein's equivalence principle asserts that local measurements cannot distinguish a system at rest in a gravitational field from one that is in uniform acceleration in empty space. Recent test-methods for the equivalence principle are presently discussed as bases for testing of dark matter scenarios involving the long-range forces between either baryonic or nonbaryonic dark matter and ordinary matter.

Frieman, Joshua A.; Gradwohl, Ben-Ami

1993-01-01

217

Convolution equivalence and distributions of random sums  

Microsoft Academic Search

A serious gap in the Proof of Pakes’s paper on the convolution equivalence of infinitely divisible distributions on the line\\u000a is completely closed. It completes the real analytic approach to Sgibnev’s theorem. Then the convolution equivalence of random\\u000a sums of IID random variables is discussed. Some of the results are applied to random walks and Lévy processes. In particular,\\u000a results

Toshiro Watanabe

2008-01-01

218

Multilingual energy dictionary. [Equivalents in 6 languages  

SciTech Connect

This dictionary covers 1600 entries - ranging from oil well to synthetic natural gas and waste heat recovery - that cover both concepts and equipment, providing the equivalents of the most-important energy terms in six languages: English, French, German, Italian, Portuguese, and Spanish. Each term is listed six times - under each language, with all five foreign equivalents - permitting easy translation among all six languages. Separate entries are also given for British and American English where usage differs in the two countries.

Isaacs, A. (ed.)

1981-01-01

219

The Nonequivalence of High School Equivalents  

Microsoft Academic Search

This article analyzes the causes and consequences of the growing proportion of high-school-certified persons who achieve that status by exam certification rather than through high school graduation. Exam-certified high school equivalents are statistically indistinguishable from high school dropouts. Whatever differences are found among exam-certified equivalents, high school dropouts and high school graduates are accounted for by their years of schooling

Stephen V. Cameron; James J. Heckman

1993-01-01

220

AMU NEXRAD Exploitation Task  

NASA Technical Reports Server (NTRS)

This report documents the results of the Applied Meteorology Unit's NEXRAD Exploitation Task. The objectives of this task are to determine what radar signatures are present prior to and at the time of convection initiation, and to determine radar signatures which will help distinguish whether the ensuing convection will become severe. Radar data from the WSR-88D radar located at NWS Melbourne (WSR-88D/KMLB) were collected between June and September 1995, and 16 convective case studies were analyzed for which the radar was operating during the entire period of interest. All WSR-88D/KMLB products were scrutinized for their utility in detecting convection initiation and severe storm signatures. Through process of elimination, it was found that the 0.5 deg reflectivity product with the lowest reflectivity values displayed is the best product to monitor for convection initiation signatures. Seven meteorological features associated with the initiation of deep convection were identified: the Merritt Island and Indian River convergence zones, interlake convergence, horizontal convective rolls, the sea breeze, storm outflow boundaries, and fires. Their reflectivity values ranged from -5 to 20 dBZ. Of the three severe weather phenomena (winds greater than or equal to 50 kts, tornado, 3/4 inch hail), high wind events due to microbursts were most common in the data set. It was found that the values and trends of composite reflectivity, vertically integrated liquid, and core aspect ratio were key indicators of the potential of a cell to produce a microburst. The data were not analyzed for the other two severe weather phenomena because they rarely occurred during the data collection period. This report also includes suggestions for new WSR-88D products, summaries of ongoing research aimed at creating new products, and explicit recommended procedures for detecting convection initiation and severe storm signatures in the radar data using the currently available technology.

Lambert, Winifred C.; Wheeler, Mark M.

1997-01-01

221

Equivalent outdoor temperature for district heating systems  

SciTech Connect

This paper focuses on the influence of various climatic variables on the mass flow in district heating systems. The aim is to establish an equation of what is called the equivalent outdoor temperature. Two possible ways of doing this are considered. In both cases, dynamic models are needed of the mass flow with climatic variables as external inputs. The resulting equation for the equivalent outdoor temperature, which may be nonlinear, shows the equivalent value of each climatic variable in degrees Celsius. Thus, the equivalent temperature can be considered a variable that contains the effect of various weather factors on the mass flow. Measurements from the daily operation of a heating company in Iceland are used in a case study. It is also shown how the uncertainty in the parameters of the equivalent temperature equation can be estimated. The results indicate that, based on the present data, a linear relation between the outdoor temperature, the wind speed, and the number of sunshine hours is adequate for describing the equivalent outdoor temperature.

Jonsson, G.R.; Jonsson, V.K. [Univ. of Iceland, Reykjavik (Iceland). Dept. of Mechanical Engineering

1995-08-01

222

Dysprosium magneto-optical traps  

E-print Network

Magneto-optical traps (MOTs) of highly magnetic lanthanides open the door to explorations of novel phases of strongly correlated matter such as lattice supersolids and quantum liquid crystals. We recently reported the first MOTs of the five high abundance isotopes of the most magnetic atom, dysprosium. Described here are details of the experimental technique employed for repumper-free Dy MOTs containing up to half a billion atoms. Extensive characterization of the MOTs' properties---population, temperature, loading, metastable decay dynamics, trap dynamics---is provided.

Seo Ho Youn; Mingwu Lu; Ushnish Ray; Benjamin L. Lev

2010-07-08

223

Dysprosium magneto-optical traps  

E-print Network

Magneto-optical traps (MOTs) of highly magnetic lanthanides open the door to explorations of novel phases of strongly correlated matter such as lattice supersolids and quantum liquid crystals. We recently reported the first MOTs of the five high abundance isotopes of the most magnetic atom, dysprosium. Described here are details of the experimental technique employed for repumper-free Dy MOTs containing up to half a billion atoms. Extensive characterization of the MOTs' properties---population, temperature, loading, metastable decay dynamics, trap dynamics---is provided.

Youn, Seo Ho; Ray, Ushnish; Lev, Benjamin L

2010-01-01

224

Dysprosium magneto-optical traps  

SciTech Connect

Magneto-optical traps (MOTs) of highly magnetic lanthanides open the door to explorations of novel phases of strongly correlated matter such as lattice supersolids and quantum liquid crystals. We recently reported the first MOTs of the five high-abundance isotopes of the most magnetic atom, dysprosium. Described here are details of the experimental technique employed for repumper-free Dy MOTs containing up to half a billion atoms. Extensive characterization of the MOTs' properties--population, temperature, loading, metastable decay dynamics, and trap dynamics--is provided.

Youn, Seo Ho; Lu Mingwu; Ray, Ushnish; Lev, Benjamin L. [Department of Physics, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801-3080 (United States)

2010-10-15

225

TRAPS AND TRAPPING TECHNIQUES FOR ADULT MOSQUITO CONTROL  

Technology Transfer Automated Retrieval System (TEKTRAN)

Research has been conducted during the past three years on the efficacy of propane powered traps to manage salt marsh mosquitoes on Atsena Otie, an isolated island in the Gulf of Mexico, located near Cedar Key, FL, USA. The target species has been Ochlerotatus taeniorhynchus. Twenty-one Mosquito Mag...

226

Microfabricated linear Paul-Straubel ion trap  

DOEpatents

An array of microfabricated linear Paul-Straubel ion traps can be used for mass spectrometric applications. Each ion trap comprises two parallel inner RF electrodes and two parallel outer DC control electrodes symmetric about a central trap axis and suspended over an opening in a substrate. Neighboring ion traps in the array can share a common outer DC control electrode. The ions confined transversely by an RF quadrupole electric field potential well on the ion trap axis. The array can trap a wide array of ions.

Mangan, Michael A. (Albuquerque, NM); Blain, Matthew G. (Albuquerque, NM); Tigges, Chris P. (Albuquerque, NM); Linker, Kevin L. (Albuquerque, NM)

2011-04-19

227

Microfluidic sorting with blinking optical traps.  

PubMed

It is shown that by appropriately choosing the periodicity of a blinking optical trap only larger sized colloidal spheres can be selectively trapped out of a mixed population. This happens because smaller sized, more agile, spheres escape out of the trap volume during the off period of the trap beam. Therefore, by scanning an array of blinking traps over a mixed sample, bigger spheres can be forced to move with the traps and eventually could be taken to the output side. Experimental demonstration of sorting between 1 µm and 2 µm diameter silica spheres is presented. PMID:22627555

Dasgupta, R; Verma, R S; Gupta, P K

2012-05-15

228

2-Dimensional Compressed Magneto-Optical Trap  

NASA Astrophysics Data System (ADS)

We present an experimental implementation of a two-dimensional equivalent of a Compressed Magneto-Optical Trap (C-MOT [1]). A Zeeman slower produces a beam of rubidium atoms with flux ˜10^11 atoms s-1, velocity ˜25 m/s, and propagation direction along the z-axis. The Zeeman-slowed atoms enter a magnetic field of the form B (?x, -?y, 0) with a magnetic-field gradient ? that increases with z. Four cooling laser beams intersect the atomic-beam axis in a manner that the value of ? increases from about 10 G cm-1 to about 50 G cm-1 within the cooling region. As a result, a magneto-optic compression effect is achieved. The velocity of the extracted, compressed atomic beam can be varied via a frequency difference among the cooling beams. In contrast to pulsed C-MOTs (see Ref. [1]), our device operates continuously, and can be used as a starting point for the preparation of continuous-wave Bose Einstein Condensates and atom lasers. Simulations comparing the two-dimensional compressed MOT with a two-dimensional MOT without compression are presented. Future directions of the experiment will be discussed. [1] W. Petrich, M. H. Anderson, J. R. Ensher, E. A. Cornell, J. Opt. Soc. Am. 11, 1332 (1994).

Mhaskar, Rahul; Vaidya, Varun; Raithel, Georg

2007-06-01

229

Towards the unification of inference structures in medical diagnostic tasks.  

PubMed

The central purpose of artificial intelligence applied to medicine is to develop models for diagnosis and therapy planning at the knowledge level, in the Newell sense, and software environments to facilitate the reduction of these models to the symbol level. The usual methodology (KADS, Common-KADS, GAMES, HELIOS, Protégé, etc) has been to develop libraries of generic tasks and reusable problem-solving methods with explicit ontologies. The principal problem which clinicians have with these methodological developments concerns the diversity and complexity of new terms whose meaning is not sufficiently clear, precise, unambiguous and consensual for them to be accessible in the daily clinical environment. As a contribution to the solution of this problem, we develop in this article the conjecture that one inference structure is enough to describe the set of analysis tasks associated with medical diagnoses. To this end, we first propose a modification of the systematic diagnostic inference scheme to obtain an analysis generic task and then compare it with the monitoring and the heuristic classification task inference schemes using as comparison criteria the compatibility of domain roles (data structures), the similarity in the inferences, and the commonality in the set of assumptions which underlie the functionally equivalent models. The equivalences proposed are illustrated with several examples. Note that though our ongoing work aims to simplify the methodology and to increase the precision of the terms used, the proposal presented here should be viewed more in the nature of a conjecture. PMID:9550854

Mira, J; Rives, J; Delgado, A E; Martínez, R

1998-01-01

230

Funnel traps capture a higher proportion of juvenile Great Tits Parus major than automatic traps  

USGS Publications Warehouse

We compared capture rates of Great Tits at funnel traps, where several birds can be captured at once so that some decoy effect may appear, to those obtained at automatic traps, where only one bird can be trapped at a time, at trapping stations in northeastern Spain. Juvenile birds were mainly captured at funnel traps (79% of juvenile captures), whereas adult plumaged birds were captured at both types of traps (51% of captures were at the funnel traps) (test between ages, P<0.001). Juvenile Great Tits had lower body condition as measured by ptilochronology (P<0.01). These birds are more easily trapped in funnel traps, which may be acting as decoy traps, and thus are vulnerable to the same kinds of biases (eg age or body condition) that have been previously documented for decoy traps.

Senar, J.C.; Domenech, J.; Conroy, M.J.

1999-01-01

231

Motor-equivalent covariation stabilizes step parameters and center of mass position during treadmill walking  

Microsoft Academic Search

We investigated motor-equivalent stabilization of task-related variables (TRV) at times of heel strike in eight healthy young\\u000a men (23–30 years) who walked on a motorized treadmill at self-selected and prescribed speeds within the normal walking speed\\u000a range. The TRV consisted of step parameters (step length and width) and the center of mass (CoM) position relative to the\\u000a support (back and front

Julius Verrel; Martin Lövdén; Ulman Lindenberger

2010-01-01

232

Prairie Dog Released from Trap  

USGS Multimedia Gallery

A prairie dog returns to its burrow in Wind Cave National Park after scientists free it from a trap. The animal is part of a field test to determine the effectiveness of a USGS-developed oral sylvatic plague vaccine (SPV). This prairie dog was previously tagged, and its blood, hair, and whisker samp...

233

Task-dependent color discrimination  

NASA Technical Reports Server (NTRS)

When color video displays are used in time-critical applications (e.g., head-up displays, video control panels), the observer must discriminate among briefly presented targets seen within a complex spatial scene. Color-discrimination threshold are compared by using two tasks. In one task the observer makes color matches between two halves of a continuously displayed bipartite field. In a second task the observer detects a color target in a set of briefly presented objects. The data from both tasks are well summarized by ellipsoidal isosensitivity contours. The fitted ellipsoids differ both in their size, which indicates an absolute sensitivity difference, and orientation, which indicates a relative sensitivity difference.

Poirson, Allen B.; Wandell, Brian A.

1990-01-01

234

Homotropic Cooperativity from the Activation Pathway of the Allosteric Ligand-Responsive Regulatory Protein TRAP†  

PubMed Central

The trp RNA-binding Attenuation Protein (TRAP) assembles into an 11-fold symmetric ring that regulates transcription and translation of trp-mRNA in bacilli via heterotropic allosteric activation by the amino acid tryptophan (Trp). Whereas nuclear magnetic resonance studies have revealed that Trp-induced activation coincides with both ?s-ms rigidification and local structural changes in TRAP, the pathway of binding of the 11 Trp ligands to the TRAP ring remains unclear. Moreover, because each of eleven bound Trp molecules is completely surrounded by protein, its release requires flexibility of Trp-bound (holo) TRAP. Here, we used stopped-flow fluorescence to study the kinetics of Trp binding by Bacillus stearothermophilus TRAP over a range of temperatures and we observed well-separated kinetic steps. These data were analyzed using non-linear least-squares fitting of several two- and three-step models. We found that a model with two binding steps best describes the data, although the structural equivalence of the binding sites in TRAP implies a fundamental change in the time-dependent structure of the TRAP rings upon Trp binding. Application of the two binding step model reveals that Trp binding is much slower than the diffusion limit, suggesting a gating mechanism that depends on the dynamics of apo TRAP. These data also reveal that Trp dissociation from the second binding mode is much slower than after the first Trp binding mode, revealing insight into the mechanism for positive homotropic allostery, or cooperativity. Temperature dependent analyses reveal that both binding modes imbue increases in bondedness and order toward a more compressed active state. These results provide insight into mechanisms of cooperative TRAP activation, and underscore the importance of protein dynamics for ligand binding, ligand release, protein activation, and allostery. PMID:24224873

Kleckner, Ian R.; McElroy, Craig A.; Kuzmic, Petr; Gollnick, Paul; Foster, Mark P.

2014-01-01

235

Equivalence of DFAs and NFAs Two accepters M1 and M2 are equivalent if  

E-print Network

1 Equivalence of DFAs and NFAs Two accepters M1 and M2 are equivalent if: L(M1) = L(M2) Trivial: Given a DFA M1, construct an equiva- lent NFA M2. Harder But Solvable: Given a NFA M1, con- struct an equivalent DFA M2. The idea is to map every subset of states in the NFA M1 to a single state in the DFA M2

Bylander, Tom

236

Collisional activation with random noise in ion trap mass spectrometry  

SciTech Connect

Random noise applied to the end caps of a quadrupole ion trap is shown to be an effective means for the collisional activation of trapped ions independent of mass/charge ratio and number of ions. This technique is compared and contrasted with conventional single-frequency collisional activation for the molecular ion of N,N-dimethylaniline, protonated cocaine, the molecular anion of 2,4,6-trinitrotoluene, and doubly protonated neuromedin U-8. Collisional activation with noise tends to produce more extensive fragmentation than the conventional approach due to the fact that product ions are also kinetically excited in the noise experiment. The efficiency of the noise experiment in producing detectable product ions relative to the conventional approach ranges from being equivalent to being a factor of 3 less efficient. Furthermore, discrimination against low mass/charge product ions is apparent in the data from multiply charged biomolecules. Nevertheless, collisional activation with random noise provides a very simple means for overcoming problems associated with the dependence of single-frequency collisional activation on mass/charge ratio and the number of ions in the ion trap. 45 refs., 7 figs.

McLuckey, S.A.; Goeringer, D.E.; Glish, G.L. [Oak Ridge National Lab., TN (United States)

1992-07-01

237

Surface-electrode point Paul trap  

E-print Network

We present a model as well as experimental results for a surface electrode radiofrequency Paul trap that has a circular electrode geometry well suited for trapping single ions and two-dimensional planar ion crystals. The ...

Chuang, Isaac L.

238

Ion Trap Quantum Computing with Ca + Ions  

Microsoft Academic Search

The scheme of an ion trap quantum computer is described and the implementation of quantum gate operations with trapped Ca+ ions is discussed. Quantum information processing with Ca+ ions is exemplified with several recent experiments investigating entanglement of ions.

R. Blatt; H. Häffner; C. F. Roos; C. Becher; F. Schmidt-Kaler

2004-01-01

239

Ion Trap Quantum Computing with Ca + Ions  

Microsoft Academic Search

The scheme of an ion trap quantum computer is described and the implementation of quantum gate operations with trapped Ca+ ions is discussed. Quantum information processing with Ca+ ions is exemplified with several recent experiments investigating entanglement of ions.

R. Blatt; H. Häffner; C. F. Roos; C. Becher; F. Schmidt-Kaler

240

Inertial measurement via dynamics of trapped particles  

E-print Network

We describe theoretical and practical aspects of the particle trap as an inertial sensor. The insight motivating this approach is that a trapped particle acts like a mass on a spring, but the restoring forces are provided ...

Post, E. Rehmi, 1966-

2003-01-01

241

Energy Savings Through Steam Trap Management  

E-print Network

energy management controls. When the topic of energy management relates to steam trap management however, the focus becomes less clear and action less notable. The seemingly “low hanging” fruit of steam traps are not often tied to significant...

Gibbs, C.

2008-01-01

242

Fiber optic integration in planar ion traps  

E-print Network

Atomic ion traps are are excellent tools in atomic physics for studying single ions. Accurate measurement of the ion's electronic state in these ion traps is required by both atomic clocks and quantum computation. Quantum ...

George, Elizabeth Marie

2008-01-01

243

Hypercube matrix computation task  

NASA Technical Reports Server (NTRS)

A major objective of the Hypercube Matrix Computation effort at the Jet Propulsion Laboratory (JPL) is to investigate the applicability of a parallel computing architecture to the solution of large-scale electromagnetic scattering problems. Three scattering analysis codes are being implemented and assessed on a JPL/California Institute of Technology (Caltech) Mark 3 Hypercube. The codes, which utilize different underlying algorithms, give a means of evaluating the general applicability of this parallel architecture. The three analysis codes being implemented are a frequency domain method of moments code, a time domain finite difference code, and a frequency domain finite elements code. These analysis capabilities are being integrated into an electromagnetics interactive analysis workstation which can serve as a design tool for the construction of antennas and other radiating or scattering structures. The first two years of work on the Hypercube Matrix Computation effort is summarized. It includes both new developments and results as well as work previously reported in the Hypercube Matrix Computation Task: Final Report for 1986 to 1987 (JPL Publication 87-18).

Calalo, Ruel H.; Imbriale, William A.; Jacobi, Nathan; Liewer, Paulett C.; Lockhart, Thomas G.; Lyzenga, Gregory A.; Lyons, James R.; Manshadi, Farzin; Patterson, Jean E.

1988-01-01

244

Hypercube matrix computation task  

NASA Technical Reports Server (NTRS)

The Hypercube Matrix Computation (Year 1986-1987) task investigated the applicability of a parallel computing architecture to the solution of large scale electromagnetic scattering problems. Two existing electromagnetic scattering codes were selected for conversion to the Mark III Hypercube concurrent computing environment. They were selected so that the underlying numerical algorithms utilized would be different thereby providing a more thorough evaluation of the appropriateness of the parallel environment for these types of problems. The first code was a frequency domain method of moments solution, NEC-2, developed at Lawrence Livermore National Laboratory. The second code was a time domain finite difference solution of Maxwell's equations to solve for the scattered fields. Once the codes were implemented on the hypercube and verified to obtain correct solutions by comparing the results with those from sequential runs, several measures were used to evaluate the performance of the two codes. First, a comparison was provided of the problem size possible on the hypercube with 128 megabytes of memory for a 32-node configuration with that available in a typical sequential user environment of 4 to 8 megabytes. Then, the performance of the codes was anlyzed for the computational speedup attained by the parallel architecture.

Calalo, R.; Imbriale, W.; Liewer, P.; Lyons, J.; Manshadi, F.; Patterson, J.

1987-01-01

245

New results for random determination of equivalence of expressions  

Microsoft Academic Search

We devise several procedures based on signatures (or hashing functions) to determine equivalence of expressions in Random Polynomial Time (also called Probabilistic Polynomial Time) (RPT). We extend the previous results known to include various new functions that can be tested. These procedures return as result: “equivalent” or “not-equivalent”. The result “not-equivalent” is always correct, while the result “equivalent” is correct

Gaston H. Gonnet

1986-01-01

246

Task Models in the Digital Ocean  

ERIC Educational Resources Information Center

The Task Model is a description of each task in a workflow. It defines attributes associated with that task. The creation of task models becomes increasingly important as the assessment tasks become more complex. Explicitly delineating the impact of task variables on the ability to collect evidence and make inferences demands thoughtfulness from…

DiCerbo, Kristen E.

2014-01-01

247

Note: Toward multiple addressable optical trapping  

PubMed Central

We describe a setup for addressable optical trapping in which a laser source is focused on a digital micromirror device and generates an optical trap in a microfluidic cell. In this paper, we report a proof-of-principle single beam?single micromirror?single three-dimensional trap arrangement that should serve as the basis for a multiple-trap instrument. PMID:20192526

Faustov, Alexei R.; Webb, Michael R.; Walt, David R.

2010-01-01

248

Continuous stopping and trapping of neutral atoms  

Microsoft Academic Search

Neutral-sodium atoms have been continuously loaded into a 0.1-K deep superconducting magnetic trap with laser light used to slow and stop them. At least 10⁹ atoms were trapped with a decay time of 2 1\\/2 min. The fluorescence of the trapped atoms was studied as a function of time; possible loss mechanisms from the trap are discussed.

V. S. Bagnato; G. P. Lafyatis; A. G. Martin; E. L. Raab; R. N. Ahmad-Bitar; D. Pritchard

1987-01-01

249

Continuous stopping and trapping of neutral atoms  

SciTech Connect

Neutral-sodium atoms have been continuously loaded into a 0.1-K deep superconducting magnetic trap with laser light used to slow and stop them. At least 10/sup 9/ atoms were trapped with a decay time of 2 1/2 min. The fluorescence of the trapped atoms was studied as a function of time; possible loss mechanisms from the trap are discussed.

Bagnato, V.S.; Lafyatis, G.P.; Martin, A.G.; Raab, E.L.; Ahmad-Bitar, R.N.

1987-05-25

250

instructions HisTrap FF crude,  

E-print Network

· p1 instructions HisTrap FF crude, 1 ml and 5 ml i 11-0012-38 Edition AA HisTrapTM FF crude, such as degradation and oxidation of sensitive target proteins, and is therefore of great importance. HisTrap FF crude properties HisTrap FF crude 1-ml and 5-ml columns are prepacked with the affinity medium Ni Sepharose 6 Fast

Lebendiker, Mario

251

Elucidation of Equivalent Current Dipole from Magnetocardiography (MCG) Measurements  

NASA Astrophysics Data System (ADS)

A method is presented for reconstructing the source parameters of an equivalent current dipole assumed to be responsible for the observed magnetic field distribution. We solve the inverse problem using an iterative nonlinear least square optimization technique. Since the inverse problem is ill-posed and its solution is non-unique, the solution may be trapped in a local minimum if the initial values are far from the exact solution. This necessitates an estimate of the source parameters to be available as a prior knowledge for choosing the initial values. Here, we assume a set of pseudorandom numbers as the initial values for the source parameters and reconstruct the solution by imposing appropriate constraints such that the position coordinates of the dipole are within the boundary occupied by the heart. The method is shown to provide the solution with reasonable accuracy even in the presence of about 15% additive random noise in a study involving simulated data. The method is used for the analysis of magnetocardiography data of a human subject recorded using a SQUID based measurement system developed at IGCAR.

Mariyappa, N.; Janawadkar, M. P.; Radhakrishnan, T. S.; Sundar, C. S.; Sengottuvel, S.; Gireesan, K.; Parasakthi, C.; Patel, Rajesh

2011-07-01

252

EMG feedback tasks reduce reflexive stiffness during force and position perturbations.  

PubMed

Force and position perturbations are widely applied to identify muscular and reflexive contributions to posture maintenance of the arm. Both task instruction (force vs. position) and the inherently linked perturbation type (i.e., force perturbations-position task and position perturbations-force tasks) affect these contributions and their mutual balance. The goal of this study is to explore the modulation of muscular and reflexive contributions in shoulder muscles using EMG biofeedback. The EMG biofeedback provides a harmonized task instruction to facilitate the investigation of perturbation type effects irrespective of task instruction. External continuous force and position perturbations with a bandwidth of 0.5-20 Hz were applied at the hand while subjects maintained prescribed constant levels of muscular co-activation using visual feedback of an EMG biofeedback signal. Joint admittance and reflexive impedance were identified in the frequency domain, and parametric identification separated intrinsic muscular and reflexive feedback properties. In tests with EMG biofeedback, perturbation type (position and force) had no effect on joint admittance and reflexive impedance, indicating task as the dominant factor. A reduction in muscular and reflexive stiffness was observed when performing the EMG biofeedback task relative to the position task. Reflexive position feedback was effectively suppressed during the equivalent EMG biofeedback task, while velocity and acceleration feedback were both decreased by approximately 37%. This indicates that force perturbations with position tasks are a more effective paradigm to investigate complete dynamic motor control of the arm, while EMG tasks tend to reduce the reflexive contribution. PMID:21717098

Forbes, Patrick A; Happee, Riender; van der Helm, Frans C T; Schouten, Alfred C

2011-08-01

253

Equivalent magnetization over the World Ocean  

NASA Astrophysics Data System (ADS)

In another presentation (Hamoudi et al., this meeting), we present the construction of a new candidate for the World Digital Magnetic Anomaly Map (WDMAM) over oceanic areas. This map is based on: (a) a more realistic forward modeling of the marine magnetic anomalies which includes remanent magnetization vectors taking into account the age and motion of the oceanic lithosphere; (b) evaluation of the equivalent magnetization by comparison of the synthetic and observed anomalies along ship tracks; and (c) adjustment of the synthetic anomaly maps using this equivalent magnetization prior to merging with the observed anomalies. A by-product of this approach is a global distribution of equivalent magnetization over the World's Ocean. Note that, because no global basement map exists for the oceanic areas, we assume a uniform, 5 km-deep and 1 km-thick magnetized layer for the forward model. The resulting equivalent magnetization is therefore relative to this over-simplistic magnetic source. A first observation is that, within the hypotheses of the forward model, the average equivalent magnetization is about 3 A/m, a value which compares well with the Natural Remanent Magnetization (NRM) measured on ancient basalt samples. As expected, the mid-ocean ridges are marked by stronger equivalent magnetizations, an observation which reflects both the stronger NRM measured at ridge axes and their shallower bathymetry (not taken into account in our forward model). More interesting is the observation of significant along-axis variations. In the North Atlantic Ocean, the Kolbeinsey and Reykjanes ridges around Iceland are marked by a very strong equivalent magnetization and the Azores Plateau by a strong one as well.. Again this may reflect the combined effect of shallower seafloor, thicker and/or more magnetized basaltic layer at hotspots. In contrast, the areas between 45 and 55°N and between 0 and 10°N (Equatorial FZ) correspond to a weak equivalent magnetization. Further south, the Mid-Atlantic Ridge displays a more uniform signature, although off-axis variations seem associated to the Tristan and St Helena hotspots. In the Indian Ocean, a strong equivalent magnetization characterizes areas of hotspot-ridge interaction such as the Gulf of Aden, the Central Indian Ridge near Rodrigues Island, the Southwest Indian Ridge near Marion Island, and the Southeast Indian Ridge near St Paul and Amsterdam Islands. A weaker one is observed in colder area, at the Australian-Antarctic Discordance and around the Rodrigues Triple Junction. The Pacific Ocean is characterized by a generally stronger equivalent magnetization, both near ridges and in abyssal plains. Time variations, i.e. along seafloor spreading flowlines, are apparent across the Mid-Atlantic and Pacific-Antarctic ridges, with highs near the ridge axis (younger than 10 Ma) and between ~83 and 60 Ma, just after the Cretaceous Normal Superchron and lows between ~60 and 10 Ma. The Mesozoic basins of the Pacific and Atlantic oceans show a weaker equivalent magnetization before ~155 Ma and a stronger one after. Basins covered by thick sediments such as the Bengal Bay, Great Australian Bight, Nova Scotia Basin, and Western Somali Basin show a very weak equivalent magnetization, reflecting both a deeper basement and a possible thermal demagnetization. Some of these variations coincide with satellite magnetic anomalies.

Dyment, J.; Hamoudi, M.; Choi, Y.; Thebault, E.; Quesnel, Y.; Roest, W. R.; Lesur, V.

2012-12-01

254

System Equivalent for Real Time Digital Simulator  

NASA Astrophysics Data System (ADS)

The purpose of this research is to develop a method of making system equivalents for the Real Time Digital Simulator (RTDS), which should enhance its capability of simulating large power systems. The proposed equivalent combines a Frequency Dependent Network Equivalent (FDNE) for the high frequency electromagnetic transients and a Transient Stability Analysis (TSA) type simulation block for the electromechanical transients. The frequency dependent characteristic for FDNE is obtained by curve-fitting frequency domain admittance characteristics using the Vector Fitting method. An approach for approximating the frequency dependent characteristic of large power networks from readily available typical power-flow data is also introduced. A new scheme of incorporating TSA solution in RTDS is proposed. This report shows how the TSA algorithm can be adapted to a real time platform. The validity of this method is confirmed with examples, including the study of a multi in-feed HVDC system based network.

Lin, Xi

2011-07-01

255

Accelerating classical charges and the equivalence principle  

E-print Network

We compare the behavior of a charged particle in a gravitational field and empty space. We resolve the apparent conflict between the Lorentz-Dirac equation and Larmor's formula of radiation by noting that the former describes an electron that is itself accelerated by an electromagnetic field. If instead, a hypothetical particle is considered that is accelerated by a non-electromagnetic force, Larmor's formula is found to be consistent with the accelerating particle's equation of motion. We consider the consequences concerning the equivalence principle and find that it is indeed violated if one demands that the same electromagnetic field be present in both the gravitational and accelerating cases; however, if one allows for the external electromagnetic fields to be different, the validity of the equivalence principle is restored. In either case, the basic idea behind the equivalence principle, which leads to a geometrized theory of gravity, remains unaffected.

Viktor T. Toth

2014-04-10

256

Quantum formulation of the Einstein Equivalence Principle  

E-print Network

Validity of just a few physical conditions comprising the Einstein Equivalence Principle (EEP) suffices to ensure that gravity can be understood as space-time geometry. EEP is therefore subject to an ongoing experimental verification, with present day tests reaching the regime where quantum mechanics becomes relevant. Here we show that the classical formulation of the EEP does not apply in such a regime. The EEP requires equivalence between the total rest mass-energy of a system, the mass-energy that constitutes its inertia, and the mass-energy that constitutes its weight. In quantum mechanics internal energy is given by a Hamiltonian operator describing dynamics of internal degrees of freedom. We therefore introduce a quantum formulation of the EEP -- equivalence between the rest, inertial and gravitational internal energy operators. We show that the validity of the classical EEP does not imply the validity of its quantum formulation, which thus requires an independent experimental verification. We reanalyse...

Zych, Magdalena

2015-01-01

257

The Problem Is Not Learning: Facilitated Acquisition of Stimulus Equivalence Classes among Low-Achieving College Students  

ERIC Educational Resources Information Center

The present study examines whether facilitated acquisition occurs in contexts when 1 stimulus in a class is emotionally evocative and the other stimuli are arbitrary or neutral. Undergraduates with high and low grade-point averages (GPA) completed a matching-to-sample task that resulted in the formation of 3 stimulus equivalence classes. Each…

Adcock, Amanda C.; Merwin, Rhonda M.; Wilson, Kelly G.; Drake, Chad E.; Tucker, Christina I.; Elliott, Camden

2010-01-01

258

Whatever Gave You That Idea? False Memories Following Equivalence Training: A Behavioral Account of the Misinformation Effect  

PubMed Central

The misinformation effect is a term used in the cognitive psychological literature to describe both experimental and real-world instances in which misleading information is incorporated into an account of an historical event. In many real-world situations, it is not possible to identify a distinct source of misinformation, and it appears that the witness may have inferred a false memory by integrating information from a variety of sources. In a stimulus equivalence task, a small number of trained relations between some members of a class of arbitrary stimuli result in a large number of untrained, or emergent relations, between all members of the class. Misleading information was introduced into a simple memory task between a learning phase and a recognition test by means of a match-to-sample stimulus equivalence task that included both stimuli from the original learning task and novel stimuli. At the recognition test, participants given equivalence training were more likely to misidentify patterns than those who were not given such training. The misinformation effect was distinct from the effects of prior stimulus exposure, or partial stimulus control. In summary, stimulus equivalence processes may underlie some real-world manifestations of the misinformation effect. PMID:22084495

Challies, Danna M; Hunt, Maree; Garry, Maryanne; Harper, David N

2011-01-01

259

Microchip-Based Trapped-Atom Clocks  

E-print Network

This is a chapter of a recently published book entitled Atom Chips, edited by Jakob Reichel and Vladan Vuletic. The contents of this chapter include: Basic Principles; Atomic-Fountain versus Trapped-Atom Clocks; Optical-Transition Clocks versus Microwave Clocks; Clocks with Magnetically Trapped Atoms--Fundamental Limits and Experimental Demonstrations; Readout in Trapped-Atom Clocks; and Spin Squeezing.

Vladan Vuletic; Ian D. Leroux; Monika H. Schleier-Smith

2011-04-20

260

Homological versus algebraic equivalence in a jacobian  

PubMed Central

Let Z be an algebraic p cycle homologous to zero in an algebraic complex manifold V. Associated to Z is a linear function ? on holomorphic (2p + 1)-forms on V, modulo periods, that vanishes if Z is algebraically equivalent to zero in V. I give a formula for ? for the case of V the jacobian of an algebraic curve C and Z=C - C? (C? = “inverse” of C?) in terms of iterated integrals of holomorphic 1-forms on C. If C is the degree 4 Fermat curve, I use this formula to show that C - C? is not algebraically equivalent to zero. PMID:16593281

Harris, Bruno

1983-01-01

261

Homological versus algebraic equivalence in a jacobian.  

PubMed

Let Z be an algebraic p cycle homologous to zero in an algebraic complex manifold V. Associated to Z is a linear function nu on holomorphic (2p + 1)-forms on V, modulo periods, that vanishes if Z is algebraically equivalent to zero in V. I give a formula for nu for the case of V the jacobian of an algebraic curve C and Z=C - C' (C' = "inverse" of C') in terms of iterated integrals of holomorphic 1-forms on C. If C is the degree 4 Fermat curve, I use this formula to show that C - C' is not algebraically equivalent to zero. PMID:16593281

Harris, B

1983-02-01

262

Equivalent circuit model of radiative heat transfer  

NASA Astrophysics Data System (ADS)

Here, we develop a theory of radiative heat transfer based on an equivalent electrical network representation for the hot material slabs in an arbitrary multilayered environment with arbitrary distribution of temperatures and electromagnetic properties among the layers. Our approach is fully equivalent to the known theories operating with the fluctuating current density, while being significantly simpler in analysis and applications. A practical example of the near-infrared heat transfer through the micron gap filled with an indefinite metamaterial is considered using the suggested method. The giant enhancement of the transferred heat compared to the case of the empty gap is shown.

Maslovski, Stanislav I.; Simovski, Constantin R.; Tretyakov, Sergei A.

2013-04-01

263

Decision paths in complex tasks  

NASA Technical Reports Server (NTRS)

Complex real world action and its prediction and control has escaped analysis by the classical methods of psychological research. The reason is that psychologists have no procedures to parse complex tasks into their constituents. Where such a division can be made, based say on expert judgment, there is no natural scale to measure the positive or negative values of the components. Even if we could assign numbers to task parts, we lack rules i.e., a theory, to combine them into a total task representation. We compare here two plausible theories for the amalgamation of the value of task components. Both of these theories require a numerical representation of motivation, for motivation is the primary variable that guides choice and action in well-learned tasks. We address this problem of motivational quantification and performance prediction by developing psychophysical scales of the desireability or aversiveness of task components based on utility scaling methods (Galanter 1990). We modify methods used originally to scale sensory magnitudes (Stevens and Galanter 1957), and that have been applied recently to the measure of task 'workload' by Gopher and Braune (1984). Our modification uses utility comparison scaling techniques which avoid the unnecessary assumptions made by Gopher and Braune. Formula for the utility of complex tasks based on the theoretical models are used to predict decision and choice of alternate paths to the same goal.

Galanter, Eugene

1991-01-01

264

Welding Series. Duty Task List.  

ERIC Educational Resources Information Center

This document contains the occupational duty/task lists for six occupations in the welding series. Each occupation is divided into a number of duties. A separate page for each duty in the occupation lists the tasks in that duty along with its code number and columns to indicate whether that particular duty has been taught and to provide space for…

Oklahoma State Dept. of Vocational and Technical Education, Stillwater. Curriculum and Instructional Materials Center.

265

Trapping and cooling of 174Yb+ ions in a microfabricated surface trap  

NASA Astrophysics Data System (ADS)

Trapped atomic ions are the leading candidate to act as individual quantum bits in a large quantum information processing system. Ion traps can be conformed to a two-dimensional surface, which provides a way to increase the number of ions while maintaining the ability to move individual ions in a two-dimensional grid. However, surface traps tend to suffer from shallow trap depths and higher motional heating rates. In this work, we report the design, fabrication, and testing of a simple gold-on-fused-silica ion trap optimized for a deep trapping potential and stable motional modes. The desirable trap characteristics include long lifetime, fully-compensated micromotion, and high secular trap frequencies that were measured using a trapped and cooled 174Yb+ ion. This trap design can be integrated with an optical cavity to enhance the ion-photon coupling.

Noek, Rachel; Kim, Taehyun; Mount, Emily; Baek, So-Young; Maunz, Peter; Kim, Jungsang

2013-08-01

266

40 CFR 125.60 - Primary or equivalent treatment requirements.  

Code of Federal Regulations, 2012 CFR

...60 Primary or equivalent treatment requirements. (a...least primary or equivalent treatment. (b) The applicant...received primary or equivalent treatment. (c)(1) An applicant...include less concentrated wastewater due to excessive inflow...

2012-07-01

267

40 CFR 125.60 - Primary or equivalent treatment requirements.  

Code of Federal Regulations, 2010 CFR

...60 Primary or equivalent treatment requirements. (a...least primary or equivalent treatment. (b) The applicant...received primary or equivalent treatment. (c)(1) An applicant...include less concentrated wastewater due to excessive inflow...

2010-07-01

268

40 CFR 125.60 - Primary or equivalent treatment requirements.  

...60 Primary or equivalent treatment requirements. (a...least primary or equivalent treatment. (b) The applicant...received primary or equivalent treatment. (c)(1) An applicant...include less concentrated wastewater due to excessive inflow...

2014-07-01

269

40 CFR 125.60 - Primary or equivalent treatment requirements.  

Code of Federal Regulations, 2011 CFR

...60 Primary or equivalent treatment requirements. (a...least primary or equivalent treatment. (b) The applicant...received primary or equivalent treatment. (c)(1) An applicant...include less concentrated wastewater due to excessive inflow...

2011-07-01

270

30 CFR 90.206 - Approved sampling devices; equivalent concentrations.  

Code of Federal Regulations, 2011 CFR

...Approved sampling devices; equivalent concentrations. 90.206...Approved sampling devices; equivalent concentrations. The concentration...determined by dividing the weight of dust in milligrams collected...converting that concentration to an equivalent concentration as...

2011-07-01

271

30 CFR 70.206 - Approved sampling devices; equivalent concentrations.  

Code of Federal Regulations, 2012 CFR

...Approved sampling devices; equivalent concentrations. 70.206...Approved sampling devices; equivalent concentrations. The concentration...determined by dividing the weight of dust in milligrams collected...converting that concentration to an equivalent concentration as...

2012-07-01

272

7 CFR 987.105 - Whole equivalent of pitted dates.  

...2014-01-01 false Whole equivalent of pitted dates. 987.105...Definitions § 987.105 Whole equivalent of pitted dates. For the purposes of this part, the whole date equivalent weight of pitted dates shall be...

2014-01-01

273

7 CFR 987.105 - Whole equivalent of pitted dates.  

Code of Federal Regulations, 2011 CFR

...2011-01-01 false Whole equivalent of pitted dates. 987.105...Definitions § 987.105 Whole equivalent of pitted dates. For the purposes of this part, the whole date equivalent weight of pitted dates shall be...

2011-01-01

274

30 CFR 90.206 - Approved sampling devices; equivalent concentrations.  

...Approved sampling devices; equivalent concentrations. 90.206...Approved sampling devices; equivalent concentrations. The concentration...determined by dividing the weight of dust in milligrams collected...converting that concentration to an equivalent concentration as...

2014-07-01

275

30 CFR 71.206 - Approved sampling devices; equivalent concentrations.  

Code of Federal Regulations, 2013 CFR

...Approved sampling devices; equivalent concentrations. 71.206...Approved sampling devices; equivalent concentrations. The concentration...determined by dividing the weight of dust in milligrams collected...converting that concentration to an equivalent concentration as...

2013-07-01

276

7 CFR 987.105 - Whole equivalent of pitted dates.  

Code of Federal Regulations, 2013 CFR

...2013-01-01 false Whole equivalent of pitted dates. 987.105...Definitions § 987.105 Whole equivalent of pitted dates. For the purposes of this part, the whole date equivalent weight of pitted dates shall be...

2013-01-01

277

30 CFR 90.206 - Approved sampling devices; equivalent concentrations.  

Code of Federal Regulations, 2012 CFR

...Approved sampling devices; equivalent concentrations. 90.206...Approved sampling devices; equivalent concentrations. The concentration...determined by dividing the weight of dust in milligrams collected...converting that concentration to an equivalent concentration as...

2012-07-01

278

30 CFR 71.206 - Approved sampling devices; equivalent concentrations.  

Code of Federal Regulations, 2011 CFR

...Approved sampling devices; equivalent concentrations. 71.206...Approved sampling devices; equivalent concentrations. The concentration...determined by dividing the weight of dust in milligrams collected...converting that concentration to an equivalent concentration as...

2011-07-01

279

30 CFR 70.206 - Approved sampling devices; equivalent concentrations.  

Code of Federal Regulations, 2011 CFR

...Approved sampling devices; equivalent concentrations. 70.206...Approved sampling devices; equivalent concentrations. The concentration...determined by dividing the weight of dust in milligrams collected...converting that concentration to an equivalent concentration as...

2011-07-01

280

30 CFR 71.206 - Approved sampling devices; equivalent concentrations.  

...Approved sampling devices; equivalent concentrations. 71.206...Approved sampling devices; equivalent concentrations. The concentration...determined by dividing the weight of dust in milligrams collected...converting that concentration to an equivalent concentration as...

2014-07-01

281

30 CFR 70.206 - Approved sampling devices; equivalent concentrations.  

Code of Federal Regulations, 2013 CFR

...Approved sampling devices; equivalent concentrations. 70.206...Approved sampling devices; equivalent concentrations. The concentration...determined by dividing the weight of dust in milligrams collected...converting that concentration to an equivalent concentration as...

2013-07-01

282

30 CFR 70.206 - Approved sampling devices; equivalent concentrations.  

Code of Federal Regulations, 2010 CFR

...Approved sampling devices; equivalent concentrations. 70.206...Approved sampling devices; equivalent concentrations. The concentration...determined by dividing the weight of dust in milligrams collected...converting that concentration to an equivalent concentration as...

2010-07-01

283

30 CFR 70.206 - Approved sampling devices; equivalent concentrations.  

...Approved sampling devices; equivalent concentrations. 70.206...Approved sampling devices; equivalent concentrations. The concentration...determined by dividing the weight of dust in milligrams collected...converting that concentration to an equivalent concentration as...

2014-07-01

284

30 CFR 71.206 - Approved sampling devices; equivalent concentrations.  

Code of Federal Regulations, 2012 CFR

...Approved sampling devices; equivalent concentrations. 71.206...Approved sampling devices; equivalent concentrations. The concentration...determined by dividing the weight of dust in milligrams collected...converting that concentration to an equivalent concentration as...

2012-07-01

285

30 CFR 90.206 - Approved sampling devices; equivalent concentrations.  

Code of Federal Regulations, 2013 CFR

...Approved sampling devices; equivalent concentrations. 90.206...Approved sampling devices; equivalent concentrations. The concentration...determined by dividing the weight of dust in milligrams collected...converting that concentration to an equivalent concentration as...

2013-07-01

286

7 CFR 987.105 - Whole equivalent of pitted dates.  

Code of Federal Regulations, 2012 CFR

...2012-01-01 false Whole equivalent of pitted dates. 987.105...Definitions § 987.105 Whole equivalent of pitted dates. For the purposes of this part, the whole date equivalent weight of pitted dates shall be...

2012-01-01

287

49 CFR 538.8 - Gallon Equivalents for Gaseous Fuels.  

Code of Federal Regulations, 2010 CFR

...false Gallon Equivalents for Gaseous Fuels. 538.8 Section 538.8 Transportation...TRANSPORTATION MANUFACTURING INCENTIVES FOR ALTERNATIVE FUEL VEHICLES § 538.8 Gallon Equivalents for Gaseous Fuels. The gallon equivalent of...

2010-10-01

288

49 CFR 538.8 - Gallon Equivalents for Gaseous Fuels.  

Code of Federal Regulations, 2011 CFR

...false Gallon Equivalents for Gaseous Fuels. 538.8 Section 538.8 Transportation...TRANSPORTATION MANUFACTURING INCENTIVES FOR ALTERNATIVE FUEL VEHICLES § 538.8 Gallon Equivalents for Gaseous Fuels. The gallon equivalent of...

2011-10-01

289

49 CFR 538.8 - Gallon Equivalents for Gaseous Fuels.  

Code of Federal Regulations, 2012 CFR

...false Gallon Equivalents for Gaseous Fuels. 538.8 Section 538.8 Transportation...TRANSPORTATION MANUFACTURING INCENTIVES FOR ALTERNATIVE FUEL VEHICLES § 538.8 Gallon Equivalents for Gaseous Fuels. The gallon equivalent of...

2012-10-01

290

49 CFR 538.8 - Gallon Equivalents for Gaseous Fuels.  

Code of Federal Regulations, 2013 CFR

...false Gallon Equivalents for Gaseous Fuels. 538.8 Section 538.8 Transportation...TRANSPORTATION MANUFACTURING INCENTIVES FOR ALTERNATIVE FUEL VEHICLES § 538.8 Gallon Equivalents for Gaseous Fuels. The gallon equivalent of...

2013-10-01

291

Are Newtonian gravitation and geometrized Newtonian gravitation theoretically equivalent?  

E-print Network

Are Newtonian gravitation and geometrized Newtonian gravitation theoretically equivalent? James to the question posed in the title is yes, at least on one natural understanding of Newtonian gravitation. I equivalence, Categorical equivalence, Gauge theory, Geometrized Newtonian gravitation 1. Introduction

Wüthrich, Christian

292

Efficacy of commercial traps and food odor attractants for mass trapping of Anastrepha ludens (Diptera: Tephritidae).  

PubMed

One of the most important factors for the success of a mass trapping strategy to control a fruit fly involves the selection of an effective trap-lure combination. Because different species of fruit flies respond differently to the physical characteristics of a trap and to bait volatiles, the evaluation of commercial traps and lures that have proved useful against other tephtrids is necessary to determine their efficacy for mass trapping of Anastrepha ludens (Loew) (Diptera: Tephritidae). Under caged conditions, a commercial hemispherical trap with lateral holes (Maxitrap Plus) proved more attractive to A. ludens (both sexes) than five other commercial traps that were all baited with hydrolyzed protein. Among these traps, bottom invaginated traps and traps with invaginated lateral holes constructed with transparent cylinders had the best physical retention properties. When evaluated under field conditions, the lure was critical for the efficacy of the trap, and one of the traps that performed poorly in attraction and retention cage tests (MS2) resulted as one of the most effective traps when baited with CeraTrap lure. Considering the use of different trap models under field conditions, CeraTrap liquid bait was more effective in A. ludens capture than Biolure dry synthetic bait, but both lures were not replaced during the entire course of the experiment. The percentage of captured females was also slightly higher using CeraTrap lure (67.2%) than using Biolure baits (54.5-58.8%). In field tests, 75-81% of females were mated and no significant differences were observed among trap-lure combinations. Trap selectivity against nontarget adult lacewings also differed among trap-lure combinations. PMID:24665702

Lasa, Rodrigo; Velázquez, Olinda E; Ortega, Rafael; Acosta, Emilio

2014-02-01

293

Trapping of diffusive particles by rough absorbing surfaces: Boundary smoothing approach  

NASA Astrophysics Data System (ADS)

We present analytical results for the first-passage statistics of Brownian particles near a comblike absorbing boundary. Our approach is based on the method of boundary homogenization (or boundary smoothing) when an equivalent flat boundary is introduced to maintain the same diffusion flux as the original rough boundary. By using the conformal invariance of the Laplace equation we derive an analytic expression for the position of an equivalent boundary in terms of its spatial period and amplitude. The main analytical results being initially obtained for the steady state system provide important insights into the statistical characteristics of diffusive transport near rough boundaries (high order moments of the trapping time statistics).

Skvortsov, A.; Walker, A.

2014-08-01

294

Electrodynamic trap for neutral polar particles  

SciTech Connect

A superposition of inhomogeneous static and rapidly oscillating electric fields is capable of trapping neutral particles with a permanent electric dipole moment. Detailed numerical simulations prove the validity and stability of our trapping scheme. Thin rods of barium titanate (BaTiO{sub 3}) are presented as an example for trapping on the macroscale. HC{sub 17}N, a polar molecule of astrophysical significance, is presented as an example for trapping on the microscale. For HC{sub 17}N and the parameters chosen, the depth of the trap is 40 mK.

Bluemel, R. [Department of Physics, Wesleyan University, Middletown, Connecticut 06459-0155 (United States)

2011-04-15

295

Simple analytic potentials for linear ion traps  

NASA Technical Reports Server (NTRS)

A simple analytical model was developed for the electric and ponderomotive (trapping) potentials in linear ion traps. This model was used to calculate the required voltage drive to a mercury trap, and the result compares well with experiments. The model gives a detailed picture of the geometric shape of the trapping potenital and allows an accurate calculation of the well depth. The simplicity of the model allowed an investigation of related, more exotic trap designs which may have advantages in light-collection efficiency.

Janik, G. R.; Prestage, J. D.; Maleki, L.

1989-01-01

296

Microscale ion trap mass spectrometer  

DOEpatents

An ion trap for mass spectrometric chemical analysis of ions is delineated. The ion trap includes a central electrode having an aperture; a pair of insulators, each having an aperture; a pair of end cap electrodes, each having an aperture; a first electronic signal source coupled to the central electrode; a second electronic signal source coupled to the end cap electrodes. The central electrode, insulators, and end cap electrodes are united in a sandwich construction where their respective apertures are coaxially aligned and symmetric about an axis to form a partially enclosed cavity having an effective radius r.sub.0 and an effective length 2z.sub.0, wherein r.sub.0 and/or z.sub.0 are less than 1.0 mm, and a ratio z.sub.0 /r.sub.0 is greater than 0.83.

Ramsey, J. Michael (Knoxville, TN); Witten, William B. (Lancing, TN); Kornienko, Oleg (Lansdale, PA)

2002-01-01

297

Pattern formation with trapped ions.  

PubMed

Ion traps are a versatile tool to study nonequilibrium statistical physics, due to the tunability of dissipation and nonlinearity. We propose an experiment with a chain of ions, where dissipation is provided by laser heating and cooling, while nonlinearity is provided by trap anharmonicity and beam shaping. The dynamics are governed by an equation similar to the complex Ginzburg-Landau equation, except that the reactive nature of the coupling leads to qualitatively different behavior. The system has the unusual feature of being both oscillatory and excitable at the same time. The patterns are observable for realistic experimental parameters despite noise from spontaneous emission. Our scheme also allows controllable experiments with noise and quenched disorder. PMID:21561187

Lee, Tony E; Cross, M C

2011-04-01

298

Electrophysiological Correlates of Stimulus Equivalence Processes  

ERIC Educational Resources Information Center

Research reported here concerns neural processes relating to stimulus equivalence class formation. In Experiment 1, two types of word pairs were presented successively to normally capable adults. In one type, the words had related usage in English (e.g., uncle, aunt). In the other, the two words were not typically related in their usage (e.g.,…

Haimson, Barry; Wilkinson, Krista M.; Rosenquist, Celia; Ouimet, Carolyn; McIlvane, William J.

2009-01-01

299

Engraftment of a vascularized human skin equivalent.  

PubMed

Clinical performance of currently available human skin equivalents is limited by failure to develop perfusion. To address this problem we have developed a method of endothelial cell transplantation that promotes vascularization of human skin equivalents in vivo. Enhancement of vascularization by Bcl-2 overexpression was demonstrated by seeding human acellular dermis grafts with human umbilical vein endothelial cells (HUVEC) transduced with the survival gene Bcl-2 or an EGFP control transgene, and subcutaneous implantation in immunodeficient mice (n=18). After 1 month the grafts with Bcl-2-transduced cells contained a significantly greater density of perfused HUVEC-lined microvessels (55.0/mm3) than controls (25.4/mm3,P=0.026). Vascularized skin equivalents were then constructed by sequentially seeding the apical and basal surfaces of acellular dermis with cultured human keratinocytes and Bcl-2-transduced HUVEC, respectively. Two weeks after orthotopic implantation onto mice, 75% of grafts (n=16) displayed both a differentiated human epidermis and perfusion through HUVEC-lined microvessels. These vessels, which showed evidence of progressive maturation, accelerated the rate of graft vascularization. Successful transplantation of such vascularized human skin equivalents should enhance clinical utility, especially in recipients with impaired angiogenesis. PMID:14656987

Schechner, Jeffrey S; Crane, Saara K; Wang, Feiya; Szeglin, Anya M; Tellides, George; Lorber, Marc I; Bothwell, Alfred L M; Pober, Jordan S

2003-12-01

300

Cement equivalence factors for fly ash  

Microsoft Academic Search

An investigation has been carried out into the cement equivalence factors for fly ash in concrete. The work was part of a prenormative research aimed at taking the contribution of fly ash to strength development and the other properties of concrete into account on the minimum cement content and maximum water-cement ratio required to achieve these properties as by the

J. Bijen; R. van Selst

1993-01-01

301

Coherency identification for power system dynamic equivalents  

Microsoft Academic Search

Coherency-based approach to the problem of constructing power system dynamic equivalents has been very successful in applications. The key step in this approach is to identify groups of coherent generators. An analytic study of coherency is conducted. An algebraic characterization of coherency is given. An algorithm, based on the algebraic characterization, to identify coherent groups directly from system data is

F. Wu; NATARAJAN NARASIMHAMURTHI

1983-01-01

302

Step (satellite Test of the Equivalence Principle)  

Microsoft Academic Search

STEP is one of a number of missions now being developed to take advantage of the quiet space environment to carry out very sensitive gravitational experiments. Using pairs of concentric free-falling proof-masses, STEP will be able to test the Equivalence Principle (EP) to a sensitivity at least five orders of magnitude better than currently achievable on ground. The EP is

T. J. Sumner; C. W. F. Everitt; J. Mester; R. Torii; P. Worden; N. Lockerbie; C. Pegrum; J. Anderson; G. Mann; J.-P. Blaser; A. M. Cruise; C. C. Speake; T. Damour; S. Vitale; H. Dittus; B. Foulon; P. Touboul; B. J. Kent; M. Sandford; Y. Jafry; R. Reinhardt; F. Loeffler; W. Vodel

2004-01-01

303

Reading adn Auditory-Visual Equivalences  

ERIC Educational Resources Information Center

A retarded boy, unable to read orally or with comprehension, was taught to match spoken to printed words and was then capable of reading comprehension (matching printed words to picture) and oral reading (naming printed words aloud), demonstrating that certain learned auditory-visual equivalences are sufficient prerequisites for reading…

Sidman, Murray

1971-01-01

304

An Essay on Equivalence of Linear Codes  

E-print Network

of linear codes: When should two linear codes be considered to be the same? · Extrinsic: permute columns treatment Definition 1 A linear code C over a field F is a k-dimensional subspace of the n-dimensional, using Hamming weight. Theorem (MacWilliams, 1961) Two linear codes C1, C2 in Fn are equivalent

Wood, Jay

305

Equivalence Postulate and Quantum Origin of Gravitation  

Microsoft Academic Search

We suggest that quantum mechanics and gravity are intimately related. In particular, we investigate the quantum Hamilton-Jacobi equation in the case of two free particles and show that the quantum potential, which is attractive, may generate the gravitational potential. The investigation, related to the formulation of quantum mechanics based on the equivalence postulate, is based on the analysis of the

Marco Matone; G. Galilei

2000-01-01

306

Identifiability and Equivalence of GLLIRM Models  

ERIC Educational Resources Information Center

The generalized logit-linear item response model (GLLIRM) is a linearly constrained nominal categories model (NCM) that computes the scale and intercept parameters for categories as a weighted sum of basic parameters. This paper addresses the problems of the identifiability of the basic parameters and the equivalence between different GLLIRM…

Revuelta, Javier

2009-01-01

307

AN UPDATE ON TECHNOLOGIES SEEKING PFRP EQUIVALENCY  

EPA Science Inventory

This presentation will: 1) Review the mandate of the Pathogen Equivalency Committee (PEC), 2) Review the PEC's current membership (of 10), 3) Discuss how a typical application is evaluated, 4) Note where information can be found by those interested in applying to the PEC, 5) List...

308

Are Aryabhata's and Galilean Relativity Equivalent?  

E-print Network

This paper considers the question of whether Aryabhata's direct and indirect references to relativity of motion are equivalent to Galilean Relativity. Examining verses fom different sections of the text Aryabhatiya, we show that there is explicit mention of relativity of space and motion, although there is no explicit reference to the motion being uniform.

R. H. Narayan

2008-02-26

309

Parametric Equivalence Scales and Scale Relativities  

Microsoft Academic Search

The authors respond to J. Banks and P. Johnson's (1994) comment on Coulter et al. (1992) drawing on a more general discussion of parametric equivalence scale and scale relativity issues and new empirical results. The authors show that criticisms of their earlier work are unfounded. When the McClements scale is properly characterized, the scale does indeed provide lower estimates of

Stephen P Jenkins; Frank A Cowell

1994-01-01

310

Equivalence and Efficiency of Image Alignment Algorithms  

Microsoft Academic Search

There are two major formulations of image alignment us- ing gradient descent. The first estimates an additive incre- ment to the parameters (the additive approach), the second an incremental warp (the compositionalapproach). We first prove that these two formulations are equivalent. A very ef- ficient algorithm was recently proposed by Hager and Bel- humeur using the additive approach that unfortunately

Simon Baker; Iain Matthews

2001-01-01

311

SUPPORT FOR USEPA'S PATHOGEN EQUIVALENCY COMMITTEE  

EPA Science Inventory

This presentation will discuss recommended and new resources for the USEPA's Pathogen Equivalency Committee including: 1) Committee's creation in 1985 and its purpose 2) Drexel University Professor Chuck Haas' 2001 report (Assessment of the PEC Process) and its findings 3) NAS/NR...

312

Biomonitoring Equivalents for bisphenol A (BPA)  

Microsoft Academic Search

Recent efforts worldwide have resulted in a growing database of measured concentrations of chemicals in blood and urine samples taken from the general population. However, few tools exist to assist in the interpretation of the measured values in a health risk context. Biomonitoring Equivalents (BEs) are defined as the concentration or range of concentrations of a chemical or its metabolite

Kannan Krishnan; Michelle Gagné; Andy Nong; Lesa L. Aylward; Sean M. Hays

2010-01-01

313

An operationalistic reformulation of Einstein's equivalence principle  

E-print Network

The Einstein's equivalence principle is formulated in terms of the accuracy of measurements and its dependence of the size of the area of measurement. It is shown that different refinements of the statement 'the spacetime is locally flat' lead to different conculsions about the spacetime geometry.

Vladik Kreinovich; R. R. Zapatrin

1997-05-30

314

Chameleonic equivalence postulate and wave function collapse  

E-print Network

A chameleonic solution to the cosmological constant problem and the non-equivalence of different conformal frames at the quantum level have been recently suggested [Phys. Rev. D82 (2010) 044006]. In this article we further discuss the theoretical grounds of that model and we are led to a chameleonic equivalence postulate (CEP). Whenever a theory satisfies our CEP (and some other additional conditions), a density-dependence of the mass of matter fields is naturally present. Let us summarize the main results of this paper. 1) The CEP can be considered the microscopic counterpart of the Einstein's Equivalence Principle and, hence, a chameleonic description of quantum gravity is obtained: in our model, (quantum) gravitation is equivalent to a conformal anomaly. 2) To illustrate one of the possible applications of the CEP, we point out a connection between chameleon fields and quantum-mechanical wave function collapse. The collapse is induced by the chameleonic nature of the theory. We discuss the collapse for a Stern-Gerlach experiment and for a diffraction experiment with electrons. More research efforts are necessary to verify whether these ideas are compatible with phenomenological constraints.

Andrea Zanzi

2014-04-03

315

Equivalent weight of humic acid from peat  

USGS Publications Warehouse

By means of discontinuous titration, the equivalent weight of humic acid isolated from a peat was found to increase from 144 to 183 between the third and fifty-second day after the humic acid was dissolved. Infra-red studies showed that the material had probably condensed with loss of carbonyl groups. ?? 1960.

Pommer, A.M.; Breger, I.A.

1960-01-01

316

Equivalent weight of humic acid from peat  

Microsoft Academic Search

By means of discontinuous titration, the equivalent weight of humic acid isolated from a peat was found to increase from 144 to 183 between the third and fifty-second day after the humic acid was dissolved. Infra-red studies showed that the material had probably condensed with loss of carbonyl groups.

A. M. Pommer; I. A. Breger

1960-01-01

317

Energy equivalence routing in wireless sensor networks  

Microsoft Academic Search

Energy is a critical resource in wireless sensor networks. In this paper, we propose a new approach to maintain network wide energy equivalence and maximize network lifetime. Compared to existing protocols, our approach emphasizes on route maintenance instead of route finding. This means no critical nodes would become the bottleneck of network lifetime. A reroute request packet is sent out

Wei Ding; S. S. Iyengar; William Rummler

318

HOW TO PASS HIGH SCHOOL EQUIVALENCY EXAMINATION.  

ERIC Educational Resources Information Center

ORGANIZED INTO A FIVE-DAY STUDY PLAN, ALLOWING ONE DAY'S STUDY TO EACH PART OF THE EQUIVALENCY EXAMINATION (SPELLING AND GRAMMAR, SOCIAL STUDIES, SCIENCE, LITERATURE, AND MATHEMATICS), THIS BOOK PROVIDES SAMPLE TESTS AND ANSWER SHEETS, A TEST SCORE RECORD AND SELF EVALUATION PROFILE, AND SUPPLEMENTARY TESTS FOR EACH SUBJECT. THE EXAMINEE CAN ORDER…

KLAGSBRUN, FRANCINE, ED.

319

Gravitational holography and trapped surfaces  

E-print Network

We have previously discussed the characteristics of the gravitational waves (GW) and have, theoretically, shown that, like the corresponding electromagnetic (EM) waves, they also demonstrate, under certain conditions, holographic properties. In this work we have expanded this discussion and show that the assumed gravitational holographic images may, theoretically, be related to another property of GW's which is their possible relation to singular (or nonsingular) trapped surfaces. We also show that this possibility may be, theoretically, related even to weak GW's.

D. Bar

2006-05-19

320

Trapping waves in Earth's plasmasphere  

NASA Astrophysics Data System (ADS)

Earth's magnetic field traps donut-shaped bands of radiation in a belt around the planet that react to solar eruptions by growing and shrinking. The Van Allen belts consist of two rings filled with particles from the solar wind and cosmic rays. Within the outer ring of the Van Allen belt sits the plasmasphere, which is the innermost part of the planet's magnetic field and home to low-energy charged particles.

Betz, Eric O.

2014-12-01

321

Relativistic Calculations for Trapped Ions  

Microsoft Academic Search

We present recent results in the field of total binding energy calculations, Land? factors, quantum electrodynamics corrections\\u000a and lifetime that are of interest for ion traps and ion sources. We describe in detail MCDF and RMBPT calculation of ionic\\u000a binding energies, which are needed for the determination of atomic masses from highly charged ion measurements. We also show\\u000a new results

P. Indelicato; E. Lindroth; T. Beier; J. Bieron; A. M. Costa; I. Lindgren; J. P. Marques; A.-M. MÅrtenson-Pendrill; M. C. Martins; M. A. Ourdane; F. Parente; P. Patté; G. C. Rodrigues; S. Salomonson; J. P. Santos

2001-01-01

322

Trapper readies trap for lizard  

NASA Technical Reports Server (NTRS)

State-licensed animal trapper James Dean sets the open door of an animal trap on KSC. He hopes to catch a large monitor lizard spotted recently near S.R. 3, a route into the Center, by several area residents. The lizard is not a native of the area, and possibly a released pet. Dean is working with the cooperation of KSC and the Merritt Island National Wildlife Refuge.

2000-01-01

323

All steam traps are not equal  

SciTech Connect

Proper selection of a steam trap will result in a long-lasting, trouble-free steam distribution system. The definition of a trap is simple enough: it should get rid of air and purge off noncondensibles when the system is started up and drain condensate anytime during operation. This is the reason traps are sometimes called automatic drain valves. A steam trap should not discharge live steam because that wastes energy and money. Steam traps are a basic requirement on a steam line, but not just any one will do. Steam systems and services differ, and so do the traps that serve them, but well-selected steam traps can do a fine job. For example, the thermal element type traps can quickly remove condensate, work in a wide range of pressure and capacity, help avoid water hammer, control corrosion by removing noncondensibles and require little maintenance. To help specify the optimum steam trap for particular service conditions and manner of operation, it is important to understand major steam trap types, with an eye to the services each one is best suited for and required maintenance. Some of the more common types of steam traps include: inverted bucket; float and thermostatic (F and T); thermodynamic or disc; bimetallic thermostatic; and thermal-element thermostatic. The different types are described and compared.

Alesson, T. [Watson McDaniel Co., Norristown, PA (United States)

1995-08-01

324

Ion traps fabricated in a CMOS foundry  

NASA Astrophysics Data System (ADS)

We demonstrate trapping in a surface-electrode ion trap fabricated in a 90-nm CMOS (complementary metal-oxide-semiconductor) foundry process utilizing the top metal layer of the process for the trap electrodes. The process includes doped active regions and metal interconnect layers, allowing for co-fabrication of standard CMOS circuitry as well as devices for optical control and measurement. With one of the interconnect layers defining a ground plane between the trap electrode layer and the p-type doped silicon substrate, ion loading is robust and trapping is stable. We measure a motional heating rate comparable to those seen in surface-electrode traps of similar size. This demonstration of scalable quantum computing hardware utilizing a commercial CMOS process opens the door to integration and co-fabrication of electronics and photonics for large-scale quantum processing in trapped-ion arrays.

Mehta, K. K.; Eltony, A. M.; Bruzewicz, C. D.; Chuang, I. L.; Ram, R. J.; Sage, J. M.; Chiaverini, J.

2014-07-01

325

Optical trapping of isolated mammalian chromosomes  

NASA Astrophysics Data System (ADS)

We have estimated the mitotic forces exerted on individual isolated mammalian chromosomes using optical trapping. The chromosomes were trapped by an optical tweezers system created by a continuous wave ytterbium laser at 1064 nm. Individual chromosomes were trapped at different in situ powers in the range of ?20-50 mW. The corresponding trapping forces were determined by a viscous drag method. In the range of laser powers used, the preliminary data show a linear relationship between the chromosome trapping forces and in situ powers. We have calculated the dimensionless trapping efficiency coefficient (Q) of the chromosomes at 1064 nm and the corresponding effects of trapping power on Q. The value of Q in our experiments was determined to be ?0.01. The results of this study validate optical tweezers as a non-invasive and precise technique to determine intracellular forces in general, and specifically, the spindle forces exerted on the chromosomes during cell division.

Khatibzadeh, Nima; Stilgoe, Alexander B.; Bui, Ann A. M.; Rocha, Yesenia; Cruz, Gladys; Nieminen, Timo A.; Rubinsztein-Dunlop, Halina; Berns, Michael W.

2014-09-01

326

Ion traps fabricated in a CMOS foundry  

E-print Network

We demonstrate trapping in a surface-electrode ion trap fabricated in a 90-nm CMOS (complementary metal-oxide-semiconductor) foundry process utilizing the top metal layer of the process for the trap electrodes. The process includes doped active regions and metal interconnect layers, allowing for co-fabrication of standard CMOS circuitry as well as devices for optical control and measurement. With one of the interconnect layers defining a ground plane between the trap electrode layer and the p-type doped silicon substrate, ion loading is robust and trapping is stable. We measure a motional heating rate comparable to those seen in surface-electrode traps of similar size. This is the first demonstration of scalable quantum computing hardware, in any modality, utilizing a commercial CMOS process, and it opens the door to integration and co-fabrication of electronics and photonics for large-scale quantum processing in trapped-ion arrays.

K. K. Mehta; A. M. Eltony; C. D. Bruzewicz; I. L. Chuang; R. J. Ram; J. M. Sage; J. Chiaverini

2014-06-13

327

Electrostatic trapping of metastable NH molecules  

SciTech Connect

We report on the Stark deceleration and electrostatic trapping of {sup 14}NH (a{sup 1}{delta}) radicals. In the trap, the molecules are excited on the spin-forbidden A{sup 3}{pi}<-a{sup 1}{delta} transition and detected via their subsequent fluorescence to the X{sup 3}{sigma}{sup -} ground state. The 1/e trapping time is 1.4{+-}0.1 s, from which a lower limit of 2.7 s for the radiative lifetime of the a{sup 1}{delta}, v=0, J=2 state is deduced. The spectral profile of the molecules in the trapping field is measured to probe their spatial distribution. Electrostatic trapping of metastable NH followed by optical pumping of the trapped molecules to the electronic ground state is an important step toward accumulation of these radicals in a magnetic trap.

Hoekstra, Steven; Metsaelae, Markus; Zieger, Peter C.; Scharfenberg, Ludwig; Gilijamse, Joop J.; Meijer, Gerard; Meerakker, Sebastiaan Y. T. van de [Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, 14195 Berlin (Germany)

2007-12-15

328

Evaluation of trapping-web designs  

USGS Publications Warehouse

The trapping web is a method for estimating the density and abundance of animal populations. A Monte Carlo simulation study is performed to explore performance of the trapping web for estimating animal density under a variety of web designs and animal behaviours. The trapping performs well when animals have home ranges, even if the home ranges are large relative to trap spacing. Webs should contain at least 90 traps. Trapping should continue for 5-7 occasions. Movement rates have little impact on density estimates when animals are confined to home ranges. Estimation is poor when animals do not have home ranges and movement rates are rapid. The trapping web is useful for estimating the density of animals that are hard to detect and occur at potentially low densities. ?? CSIRO 2005.

Lukacs, P.M.; Anderson, D.R.; Burnham, K.P.

2005-01-01

329

Ion-trapping properties of SCRIT  

NASA Astrophysics Data System (ADS)

We have developed a novel internal target formation technique, SCRIT (Self-Confining Radioactive-isotope Ion Target) with the aim to achieve electron scattering off unstable nuclei. This technique is based on the ion trapping phenomenon in an electron storage ring. To establish the applicability of SCRIT as a target formation technique, we studied in detail its ion-trapping properties. We focused particularly on the spatial distribution of the trapped target ions and their behavior in time evolution. Over 90% of injected ions were trapped in SCRIT, and the overlap efficiency between the trapped target ion cloud and the electron beam was about 10%. From time evolution measurements and computer simulations, we found that variations in trapping lifetime depending on electron beam instability, space charge effect, and q/A values are crucial to understanding the ion-trapping mechanism of SCRIT.

Ogawara, R.; Ohnishi, T.; Togasaki, M.; Tamaki, S.; Miyashita, Y.; Takehara, H.; Koizumi, K.; Kurita, K.; Wakasugi, M.

2013-12-01

330

Resolving Task Rule Incongruence during Task Switching by Competitor Rule Suppression  

ERIC Educational Resources Information Center

Task switching requires maintaining readiness to execute any task of a given set of tasks. However, when tasks switch, the readiness to execute the now-irrelevant task generates interference, as seen in the task rule incongruence effect. Overcoming such interference requires fine-tuned inhibition that impairs task readiness only minimally. In an…

Meiran, Nachshon; Hsieh, Shulan; Dimov, Eduard

2010-01-01

331

The Composite Insect Trap: An Innovative Combination Trap for Biologically Diverse Sampling  

PubMed Central

Documentation of insect diversity is an important component of the study of biodiversity, community dynamics, and global change. Accurate identification of insects usually requires catching individuals for close inspection. However, because insects are so diverse, most trapping methods are specifically tailored to a particular taxonomic group. For scientists interested in the broadest possible spectrum of insect taxa, whether for long term monitoring of an ecosystem or for a species inventory, the use of several different trapping methods is usually necessary. We describe a novel composite method for capturing a diverse spectrum of insect taxa. The Composite Insect Trap incorporates elements from four different existing trapping methods: the cone trap, malaise trap, pan trap, and flight intercept trap. It is affordable, resistant, easy to assemble and disassemble, and collects a wide variety of insect taxa. Here we describe the design, construction, and effectiveness of the Composite Insect Trap tested during a study of insect diversity. The trap catches a broad array of insects and can eliminate the need to use multiple trap types in biodiversity studies. We propose that the Composite Insect Trap is a useful addition to the trapping methods currently available to ecologists and will be extremely effective for monitoring community level dynamics, biodiversity assessment, and conservation and restoration work. In addition, the Composite Insect Trap will be of use to other insect specialists, such as taxonomists, that are interested in describing the insect taxa in a given area. PMID:21698160

Russo, Laura; Stehouwer, Rachel; Heberling, Jacob Mason; Shea, Katriona

2011-01-01

332

Representing Identity and Equivalence for Scientific Data  

NASA Astrophysics Data System (ADS)

Matters of equivalence and identity are central to the stewardship of scientific data. In order to properly prepare for and manage the curation, preservation and sharing of digitally-encoded data, data stewards must be able to characterize and assess the relationships holding between data-carrying digital resources. However, identity-related questions about resources and their information content may not be straightforward to answer: for example, what exactly does it mean to say that two files contain the same data, but in different formats? Information content is frequently distinguished from particular representations, but there is no adequately developed shared understanding of what this really means and how the relationship between content and its representations hold. The Data Concepts group at the Center for Informatics Research in Science and Scholarship (CIRSS), University of Illinois at Urbana Champaign, is developing a logic-based framework of fundamental concepts related to scientific data to support curation and integration. One project goal is to develop precise accounts of information resources carrying the same data. We present two complementary conceptual models for information representation: the Basic Representation Model (BRM) and the Systematic Assertion Model (SAM). We show how these models provide an analytical account of digitally-encoded scientific data and a precise understanding of identity and equivalence. The Basic Representation Model identifies the core entities and relationships involved in representing information carried by digital objects. In BRM, digital objects are symbol structures that express propositional content, and stand in layered encoding relationships. For example, an RDF description may be serialized as either XML or N3, and those expressions in turn may be encoded as either UTF-8 or UTF-16 sequences. Defining this encoding stack reveals distinctions necessary for a precise account of identity and equivalence relationships. The Systematic Assertion Model focuses on key provenance events through which propositional content and symbol structures acquire the status of data content and data, respectively. Attention is on events such as a selection of symbols to express propositional content, or an appeal to observational evidence to advance a claim. SAM explicitly identifies data as the primary form of expression the one directly expressing content for a systematic assertion, an assertion where claims are warranted by an observation or a computation event. Under these models, equivalence relationships may hold between different data expressing the same content, or between different encodings of the same data. Equivalence relationships also hold among different data supporting the same claim and when contrasting claims are based on the same observations. SAM and BRM support a fine-grained characterization of scientific equivalence relationships that can be documented through ordinary data stewardship practices.

Wickett, K. M.; Sacchi, S.; Dubin, D.; Renear, A. H.

2012-12-01

333

Voluntary Task Switching: Chasing the Elusive Homunculus  

ERIC Educational Resources Information Center

In the voluntary task switching procedure, subjects choose the task to perform on a series of bivalent stimuli, requiring top-down control of task switching. Experiments 1-3 contrasted voluntary task switching and explicit task cuing. Choice behavior showed small, inconsistent effects of external stimulus characteristics, supporting the assumption…

Arrington, Catherine M.; Logan, Gordon D.

2005-01-01

334

Electrokinetic trapping at the one nanometer limit  

PubMed Central

Anti-Brownian electrokinetic traps have been used to trap and study the free-solution dynamics of large protein complexes and long chains of DNA. Small molecules in solution have thus far proved too mobile to trap by any means. Here we explore the ultimate limits on trapping single molecules. We developed a feedback-based anti-Brownian electrokinetic trap in which classical thermal noise is compensated to the maximal extent allowed by quantum measurement noise. We trapped single fluorophores with a molecular weight of < 1 kDa and a hydrodynamic radius of 6.7 ? for longer than one second, in aqueous buffer at room temperature. This achievement represents an 800-fold decrease in the mass of objects trapped in solution, and opens the possibility to trap and manipulate any soluble molecule that can be fluorescently labeled. To illustrate the use of this trap, we studied the binding of unlabeled RecA to fluorescently labeled single-stranded DNA. Binding of RecA induced changes in the DNA diffusion coefficient, electrophoretic mobility, and brightness, all of which were measured simultaneously and on a molecule-by-molecule basis. This device greatly extends the size range of molecules that can be studied by room temperature feedback trapping, and opens the door to further studies of the binding of unmodified proteins to DNA in free solution. PMID:21562206

Fields, Alexander P.; Cohen, Adam E.

2011-01-01

335

IGDS/TRAP Interface Program (ITIP). Software User Manual (SUM). [network flow diagrams for coal gasification studies  

NASA Technical Reports Server (NTRS)

This specification establishes the requirements, concepts, and preliminary design for a set of software known as the IGDS/TRAP Interface Program (ITIP). This software provides the capability to develop at an Interactive Graphics Design System (IGDS) design station process flow diagrams for use by the NASA Coal Gasification Task Team. In addition, ITIP will use the Data Management and Retrieval System (DMRS) to maintain a data base from which a properly formatted input file to the Time-Line and Resources Analysis Program (TRAP) can be extracted. This set of software will reside on the PDP-11/70 and will become the primary interface between the Coal Gasification Task Team and IGDS, DMRS, and TRAP. The user manual for the computer program is presented.

Jefferys, S.; Johnson, W.; Lewis, R.; Rich, R.

1981-01-01

336

High quality atomic-layer-deposited ultrathin Si-nitride gate dielectrics with low density of interface and bulk traps  

NASA Astrophysics Data System (ADS)

Interface trap and bulk trap densities of atomic-layer-deposited (ALD) Si-nitride dielectrics have been evaluated by bipolar-voltage-pulse-induced current and electrical-stress-induced leakage-current measurements, respectively. In comparison with the conventional SiO2 dielectrics, significantly lower (˜1/3) interface trap density near the conduction band edge is observed in the ALD Si-nitride dielectrics. Moreover, the observed lower interface and bulk trap generations consistently explain the soft-breakdown-free phenomena observed in capacitors with the ALD Si-nitride gate dielectrics. Enhanced dielectric reliability and several other significant features have made the ALD Si-nitride gate dielectrics a front line candidate for extremely thin (equivalent oxide thickness ˜1 nm) gate dielectrics of sub-100-nm technology nodes.

Nakajima, Anri; Khosru, Quazi D. M.; Yoshimoto, Takashi; Kasai, Tetsurou; Yokoyama, Shin

2003-07-01

337

Dynamic trapping and two-dimensional transport of swimming microorganisms using a rotating magnetic microrobot.  

PubMed

Manipulation of microorganisms with intrinsic motility is a challenging yet important task for many biological and biomedical applications. Currently, such a task has only been accomplished using optical tweezers, while at the risk of averse heating and photodamage of the biological samples. Here, we proposed a new micro-robotic approach for fluidic trapping and two-dimensional transportation of motile microorganisms near a solid surface in fluids. We demonstrated selective trapping and transportation of individual freely swimming multi-flagellated bacteria over a distance of 30 ?m (7.5 body length of the carrier) on a surface, using the rotational flows locally induced by a rotating magnetic microparticle. Only a weak uniform magnetic field (<3 mT) was applied to actuate the microparticle. The microparticle can translate on a glass substrate by rotating at a speed of up to 100 ?m s(-1), while providing a fluidic force of a few to tens of pico-Newtons. PMID:24663401

Ye, Zhou; Sitti, Metin

2014-07-01

338

On equivalent resistance of electrical circuits  

NASA Astrophysics Data System (ADS)

While the standard (introductory physics) way of computing the equivalent resistance of nontrivial electrical circuits is based on Kirchhoff's rules, there is a mathematically and conceptually simpler approach, called the method of nodal potentials, whose basic variables are the values of the electric potential at the circuit's nodes. In this paper, we review the method of nodal potentials and illustrate it using the Wheatstone bridge as an example. We then derive a closed-form expression for the equivalent resistance of a generic circuit, which we apply to a few sample circuits. The result unveils a curious interplay between electrical circuits, matrix algebra, and graph theory and its applications to computer science. The paper is written at a level accessible by undergraduate students who are familiar with matrix arithmetic. Additional proofs and technical details are provided in appendices.

Kagan, Mikhail

2015-01-01

339

Fucoidan promotes the reconstruction of skin equivalents.  

PubMed

In this study we investigated the effects of fucoidan on the proliferation of fibroblasts and the reconstruction of a skin equivalent (SE). Fucoidan significantly stimulated the proliferation of CCD-25Sk human fibroblasts and Western blot analysis demonstrated that fucoidan markedly increased the expression of cyclin D1 and decreased the expression of p27. Fucoidan was used to reconstruct SE. Immunohistochemical staining showed that the addition of fucoidan to dermal equivalents increased expression of proliferating cell nuclear antigen (PCNA) and p63. In addition, expression of ?6-integrin was significantly increased by fucoidan, whereas expression of ?1-integrin, type 1 collagen, elastin, fibronectin did not markedly change. These results suggest that fucoidan has positive effects on epidermal reconstruction and will therefore be beneficial in the reconstruction of SE. PMID:25177165

Song, Yu Seok; Li, Hailan; Balcos, Marie Carmel; Yun, Hye-Young; Baek, Kwang Jin; Kwon, Nyoun Soo; Choi, Hye-Ryung; Park, Kyoung-Chan; Kim, Dong-Seok

2014-08-01

340

Satellite Test of the Equivalence Principle (STEP)  

NASA Technical Reports Server (NTRS)

This grant provided support for the STEP (Satellite Test of the Equivalence Principle) program between October 1991 and September 1993. STEP, previously supported by NASA under Grant NAG8-837 'A Satellite Test of the Equivalence Principle,' was selected by the European Space Agency for a Phase A study as a candidate for ESA's next medium size mission (M2). STEP was conceived as a joint NASA/ESA mission with equal participation by both agencies. ESA's contribution to the program would be the spacecraft; NASA would provide the launcher and half of the instrument, while the other half of the instrument would be provided by various European agencies. STEP was in competition with three other programs, INTEGRAL, PRISMA, and MARSNET. The final selection of a single mission for M2 took place in April 1993. STEP was not selected for M2 but made a very close second. The program is continuing in modified form.

Worden, Paul

1994-01-01

341

Texas A&M Penning Trap Facility - Design of the Measurement Trap  

E-print Network

A tandem Penning trap facility has been designed and is under construction at the Texas A&M University Cyclotron Institute (TAMU-TRAP). The initial experimental program will be the study of correlation parameters for T=2 superallowed beta-delayed proton emitters. The measurement trap is a unique large-bore optimized 5-electrode cylindrical Penning trap, which features a 90 mm free radius, larger than in any existing Penning trap. This novel geometry allows for full radial containment of decay products of interest. The trap has also been designed to exhibit a "tunable" and "orthogonalized" geometry, which is useful for alternate experiments.

M. Mehlman; D. Melconian; P. D. Shidling

2012-08-20

342

THIN EQUIVALENCE RELATIONS AND INNER MODELS PHILIPP SCHLICHT  

E-print Network

THIN EQUIVALENCE RELATIONS AND INNER MODELS PHILIPP SCHLICHT Abstract. We describe the inner models with representatives in all equiv- alence classes of thin equivalence relations in a given projective pointclass does not add equivalence classes to thin projective equivalence relations. For example, we show

Schlicht, Philipp

343

Light Trapping for High Efficiency Heterojunction Crystalline Si Solar Cells: Preprint  

SciTech Connect

Light trapping plays an important role to achieve high short circuit current density (Jsc) and high efficiency for amorphous/crystalline Si heterojunction solar cells. Si heterojunction uses hydrogenated amorphous Si for emitter and back contact. This structure of solar cell posses highest open circuit voltage of 0.747 V at one sun for c-Si based solar cells. It also suggests that over 25% record-high efficiency is possible with further improvement of Jsc. Light trapping has two important tasks. The first one is to reduce the surface reflectance of light to zero for the solar spectrum that Si has a response. The second one is to increase the effective absorption length to capture all the photon. For Si heterojunction solar cell, surface texturing, anti-reflectance indium tin oxides (ITO) layer at the front and back are the key area to improve the light trapping.

Wang, Q.; Xu, Y.; Iwaniczko, E.; Page, M.

2011-04-01

344

Quantum mechanics from an equivalence principle  

SciTech Connect

The authors show that requiring diffeomorphic equivalence for one-dimensional stationary states implies that the reduced action S{sub 0} satisfies the quantum Hamilton-Jacobi equation with the Planck constant playing the role of a covariantizing parameter. The construction shows the existence of a fundamental initial condition which is strictly related to the Moebius symmetry of the Legendre transform and to its involutive character. The universal nature of the initial condition implies the Schroedinger equation in any dimension.

Faraggi, A.E. [Univ. of Florida, Gainesville, FL (United States). Inst. for Fundamental Theory; Matone, M. [Univ. of Padova (Italy)

1997-05-15

345

On the equivalence theorem for integrable systems  

E-print Network

We investigate the equivalence theorem for integrable systems using two formulations of the Alday-Arutyunov-Frolov model. We show that the S-matrix is invariant under the field transformation which reduces the non-linear Dirac brackets of one formulation into the standard commutation relations in the second formulation. We also explain how to perform the direct diagonalization of the transformed Hamiltonian by constructing the states corresponding to self-adjoint extensions.

Melikyan, A; Rivelles, V O

2014-01-01

346

On the equivalence theorem for integrable systems  

E-print Network

We investigate the equivalence theorem for integrable systems using two formulations of the Alday-Arutyunov-Frolov model. We show that the S-matrix is invariant under the field transformation which reduces the non-linear Dirac brackets of one formulation into the standard commutation relations in the second formulation. We also explain how to perform the direct diagonalization of the transformed Hamiltonian by constructing the states corresponding to self-adjoint extensions.

A. Melikyan; E. Pereira; V. O. Rivelles

2014-12-03

347

Equivalent circuit representation of lossy coplanar waveguides  

Microsoft Academic Search

The study of the dispersion properties of planar transmission lines including metallic losses with the generalized transverse\\u000a resonance method is formalized in building an equivalent network of the cross-section which specifies the relationships between\\u000a the tangential components of the fields on each side of the interfaces. Virtual sources represent the trial quantities chosen\\u000a to describe the problem. With twoport type

F. Bouzidi; H. Aubert; D. Bajon; H. Baudrand; V. Fouad Hanna

1992-01-01

348

Capacitors with low equivalent series resistance  

NASA Technical Reports Server (NTRS)

An electric double layer capacitor (EDLC) in a coin or button cell configuration having low equivalent series resistance (ESR). The capacitor comprises mesh or other porous metal that is attached via conducting adhesive to one or both the current collectors. The mesh is embedded into the surface of the adjacent electrode, thereby reducing the interfacial resistance between the electrode and the current collector, thus reducing the ESR of the capacitor.

Fleig, Patrick Franz (Inventor); Lakeman, Charles D. E. (Inventor); Fuge, Mark (Inventor)

2011-01-01

349

Equivalent Circuit Modeling of Hysteresis Motors  

SciTech Connect

We performed a literature review and found that many equivalent circuit models of hysteresis motors in use today are incorrect. The model by Miyairi and Kataoka (1965) is the correct one. We extended the model by transforming it to quadrature coordinates, amenable to circuit or digital simulation. 'Hunting' is an oscillatory phenomenon often observed in hysteresis motors. While several works have attempted to model the phenomenon with some partial success, we present a new complete model that predicts hunting from first principles.

Nitao, J J; Scharlemann, E T; Kirkendall, B A

2009-08-31

350

Kinetic Energy and the Equivalence Principle  

E-print Network

According to the general theory of relativity, kinetic energy contributes to gravitational mass. Surprisingly, the observational evidence for this prediction does not seem to be discussed in the literature. I reanalyze existing experimental data to test the equivalence principle for the kinetic energy of atomic electrons, and show that fairly strong limits on possible violations can be obtained. I discuss the relationship of this result to the occasional claim that ``light falls with twice the acceleration of ordinary matter.''

S. Carlip

1999-09-03

351

TNT equivalency of M10 propellant  

NASA Technical Reports Server (NTRS)

Peak, side-on blast overpressure and scaled, positive impulse have been measured for M10 single-perforated propellant, web size 0.018 inches, using configurations that simulate the handling of bulk material during processing and shipment. Quantities of 11.34, 22.7, 45.4, and 65.8 kg were tested in orthorhombic shipping containers and fiberboard boxes. High explosive equivalency values for each test series were obtained as a function of scaled distance by comparison to known pressure, arrival time and impulse characteristics for hemispherical TNT surface bursts. The equivalencies were found to depend significantly on scaled distance, with higher values of 150-100 percent (pressure) and 350-125 percent (positive impulse) for the extremes within the range from 1.19 to 3.57 m/cube root of kg. Equivalencies as low as 60-140 percent (pressure) and 30-75 percent (positive impulse) were obtained in the range of 7.14 to 15.8 m/cube root of kg. Within experimental error, both peak pressure and positive impulse scaled as a function of charge weight for all quantities tested in the orthorhombic configuration.

Mcintyre, F. L.; Price, P.

1978-01-01

352

Quantum formulation of the Einstein Equivalence Principle  

E-print Network

Validity of just a few physical conditions comprising the Einstein Equivalence Principle (EEP) suffices to ensure that gravity can be understood as space-time geometry. EEP is therefore subject to an ongoing experimental verification, with present day tests reaching the regime where quantum mechanics becomes relevant. Here we show that the classical formulation of the EEP does not apply in such a regime. The EEP requires equivalence between the total rest mass-energy of a system, the mass-energy that constitutes its inertia, and the mass-energy that constitutes its weight. In quantum mechanics internal energy is given by a Hamiltonian operator describing dynamics of internal degrees of freedom. We therefore introduce a quantum formulation of the EEP -- equivalence between the rest, inertial and gravitational internal energy operators. We show that the validity of the classical EEP does not imply the validity of its quantum formulation, which thus requires an independent experimental verification. We reanalyse some already completed experiments with respect to the quantum EEP and discuss to which extent they allow testing its various aspects.

Magdalena Zych; Caslav Brukner

2015-02-03

353

Measurement equivalence in mixed mode surveys  

PubMed Central

Surveys increasingly use mixed mode data collection (e.g., combining face-to-face and web) because this controls costs and helps to maintain good response rates. However, a combination of different survey modes in one study, be it cross-sectional or longitudinal, can lead to different kinds of measurement errors. For example, respondents in a face-to-face survey or a web survey may interpret the same question differently, and might give a different answer, just because of the way the question is presented. This effect of survey mode on the question-answer process is called measurement mode effect. This study develops methodological and statistical tools to identify the existence and size of mode effects in a mixed mode survey. In addition, it assesses the size and importance of mode effects in measurement instruments using a specific mixed mode panel survey (Netherlands Kinship Panel Study). Most measurement instruments in the NKPS are multi-item scales, therefore confirmatory factor analysis (CFA) will be used as the main analysis tool, using propensity score methods to correct for selection effects. The results show that the NKPS scales by and large have measurement equivalence, but in most cases only partial measurement equivalence. Controlling for respondent differences on demographic variables, and on scale scores from the previous uni-mode measurement occasion, tends to improve measurement equivalence, but not for all scales. The discussion ends with a review of the implications of our results for analyses employing these scales.

Hox, Joop J.; De Leeuw, Edith D.; Zijlmans, Eva A. O.

2015-01-01

354

77 FR 32632 - Ambient Air Monitoring Reference and Equivalent Methods: Designation of Three New Equivalent Methods  

Federal Register 2010, 2011, 2012, 2013

...equivalent method is identified as follows: EQNA-0512-200, ``Teledyne--Advanced Pollution Instrumentation, Inc. Model 200EUP...analyzer models are commercially available from the applicant, Teledyne-API, 9480 Carroll Park Drive San Diego, CA...

2012-06-01

355

Nonspecificity and theory of mind: new evidence from a nonverbal false-sign task and children with autism spectrum disorders.  

PubMed

Understanding of false belief has long been considered to be a crucial aspect of "theory of mind" that can be explained by a domain-specific mechanism. We argue against this claim using new evidence from a nonverbal false representation task (false-sign task) with typically developing children and children with autism spectrum disorders (ASD). Experiments 1 and 2 showed that typically developing children (mean age=62.67months) were equivalent in their performance across nonverbal and verbal forms of both the false-belief and false-sign tasks. Results for these two misrepresentation tasks differed from the results of an outdated representation task ("false"-photograph task). Experiment 3 showed that children with ASD had difficulties with the false representation tasks, and this could not be explained by executive functioning or language impairments. These findings support the view that children with ASD might not have a specific theory-of-mind deficit. PMID:24508666

Iao, Lai-Sang; Leekam, Susan R

2014-06-01

356

Equivalent Structures on Sets: Equivalence Classes, Partitions and Fiber Structures of Functions  

ERIC Educational Resources Information Center

This study reports on how students can be led to make meaningful connections between such structures on a set as a partition, the set of equivalence classes determined by an equivalence relation and the fiber structure of a function on that set (i.e., the set of preimages of all sets {b} for b in the range of the function). In this paper, I first…

Hamdan, May

2006-01-01

357

C Copyright 2007 Agilent Technologies Agilent 4396B Network/Spectrum/Impedance Analyzer Task Reference  

E-print Network

cable. Contact your local Agilent Technologies sales representative or authorized service companyC Copyright 2007 Agilent Technologies Agilent 4396B Network/Spectrum/Impedance Analyzer Task measurement (page 3-3) to the following. Converting to a Different Equivalent Noise Bandwidth 1. Calculate

Anlage, Steven

358

A Study of the Concurrent Validity of a Group Reasoning Test Built from Piaget's Tasks.  

ERIC Educational Resources Information Center

Researchers have attempted to develop paper and pencil Piagetian tests that yield results equivalent to manipulative Piagetian tasks and that can be administered in significantly less time. This study is an attempt to partially replicate and extend the findings of research by Paul Ankeny and Lyle Joyce who found significant positive correlations…

Stefanich, Greg; And Others

359

Human computation tasks with global constraints  

E-print Network

An important class of tasks that are underexplored in current human computation systems are complex tasks with global constraints. One example of such a task is itinerary planning, where solutions consist of a sequence of ...

Zhang, Haoqi

360

Task-space setpoint control of robots with dual task-space information  

E-print Network

In conventional task-space control problem of robots, a single task-space information is used for the entire task. When the task-space control problem is formulated in image space, this implies that visual feedback is used ...

Cheah, C. C.

361

Introduced species as evolutionary traps  

USGS Publications Warehouse

Invasive species can alter environments in such a way that normal behavioural decision-making rules of native species are no longer adaptive. The evolutionary trap concept provides a useful framework for predicting and managing the impact of harmful invasive species. We discuss how native species can respond to changes in their selective regime via evolution or learning. We also propose novel management strategies to promote the long-term co-existence of native and introduced species in cases where the eradication of the latter is either economically or biologically unrealistic.

Schlaepfer, M.A.; Sherman, P.W.; Blossey, B.; Runge, M.C.

2005-01-01

362

Trapped iron measured on LDEF  

NASA Technical Reports Server (NTRS)

Heavy ions far below the cutoff energy were detected on the 28.5 deg inclination orbit of LDEF in a plastic track detector experiment. The Fe-group particles show a constant energy spectrum at 50 less than or equal to E less than or equal to 200 MeV/nuc. The steep energy spectrum of Fe-particles at 20 less than or equal to E less than or equal to 50 MeV/nuc and the arrival directions of these ions is consistent with a trapped component incident in the South Atlantic Anomaly at values of L=1.4-1.6.

Beaujean, R.; Jonathal, D.; Barz, S.; Enge, W.

1995-01-01

363

The effect of hierarchical task representations on task selection in voluntary task switching.  

PubMed

The current study explored the potential for hierarchical representations to influence action selection during voluntary task switching. Participants switched between 4 individual task elements. In Experiment 1, participants were encouraged to represent the task elements as grouped within a hierarchy based on experimental manipulations of varying complexity. Manipulations implemented only during the practice phase of the experiment failed to influence action selection; however, manipulations that persisted throughout the experiment influenced action selection in a manner suggestive of a hierarchical task representation. Experiment 2 demonstrated that, once established, the influences of hierarchical representations appear to persist, regardless of whether they are required. The results suggest that hierarchical representations may play a functional role of goal shielding in action selection. PMID:23421506

Weaver, Starla M; Arrington, Catherine M

2013-07-01

364

Tube length-assisted optimized aerosol trapping  

NASA Astrophysics Data System (ADS)

Trapping a single aerosol using optical tweezers could be of great importance for environmental sciences. Though a single nanoparticle as small as 10 nm is successfully trapped in aqueous media using optical tweezers, due to spherical aberration only large clusters of nanoparticles were stably trapped in air. In this paper we provide our theoretical and experimental results on optimized trapping of aerosols as small as 400 nm in radius by the introduction of an extra spherical aberration source in order to minimize the total spherical aberration of the system. Our method allows for trapping of high refractive index particles such as polystyrene beads in air. It also provides considerably large trappable depth range which endows in-depth trapping. Our theoretical and experimental results are in very good agreement.

Taheri, S. Mohammad-Reza; Sadeghi, Mohammad; Madadi, Ebrahim; S. Reihani, S. Nader

2014-10-01

365

Dielectrophoretic Traps for Single-Particle Patterning  

PubMed Central

We present a novel microfabricated dielectrophoretic trap designed to pattern large arrays of single cells. Because flowing away untrapped cells is often the rate-limiting step during cell patterning, we designed the trap to be strong enough to hold particles against practical flow rates. We experimentally validated the trap strength by measuring the maximum flow rate that polystyrene beads could withstand while remaining trapped. These bead experiments have shown excellent agreement with our model predictions, without the use of fitting parameters. The model was able to provide us with a fundamental understanding of how the traps work, and additionally allowed us to establish a set of design rules for optimizing the traps for a wide range of cell sizes. We provide the foundations for an enabling technology that can be used to pattern cells in unique ways, allowing us to do novel cell biology experiments at the microscale. PMID:15613624

Rosenthal, Adam; Voldman, Joel

2005-01-01

366

Voluntary Task Switching: Chasing the Elusive Homunculus  

Microsoft Academic Search

In the voluntary task switching procedure, subjects choose the task to perform on a series of bivalent stimuli, requiring top-down control of task switching. Experiments 1–3 contrasted voluntary task switching and explicit task cuing. Choice behavior showed small, inconsistent effects of external stimulus characteristics, supporting the assumption of top-down control of task choice. Switch costs were smaller when subjects chose

Catherine M. Arrington; Gordon D. Logan

2005-01-01

367

Reduce Steam Trap Failures at Chambers Works  

E-print Network

Reduce Steam Trap Failures at Chambers Works GB/BB Name: Cyndi Kouba Mentor/MBB: Andrew Degraff Team Members Michael Crowley(Site Energy Lead), (Charlie) Flanigan (Aramids-maintenance), Ben Snyder (Aramids-ATO), Michael Scruggs (Central... Maintenance Mechanic), Rick Ragsdale (Fluor), Joyce Finkle (PC), Denis P Humphreys (Fluoroproducts), Jack Hemmert, Charlie Brown 10/20/2010 2 Steam trap failures are nothing new Steam trap programs are nothing new WHAT makes this program have such a huge...

Kouba, C.

368

New Trapping Mechanism in Carbon Sequestration  

Microsoft Academic Search

The modes of geologic storage of CO2 are usually categorized as structural, dissolution, residual, and mineral trapping. Here we argue that the heterogeneity\\u000a intrinsic to sedimentary rocks gives rise to a fifth category of storage, which we call local capillary trapping. Local capillary\\u000a trapping occurs during buoyancy-driven migration of bulk phase CO2 within a saline aquifer. When the rising CO2

Ehsan Saadatpoor; Steven L. Bryant; Kamy Sepehrnoori

2010-01-01

369

Improved Linear-Ion-Trap Frequency Standard  

NASA Technical Reports Server (NTRS)

Improved design concept for linear-ion-trap (LIT) frequency-standard apparatus proposed. Apparatus contains lengthened linear ion trap, and ions processed alternately in two regions: ions prepared in upper region of trap, then transported to lower region for exposure to microwave radiation, then returned to upper region for optical interrogation. Improved design intended to increase long-term frequency stability of apparatus while reducing size, mass, and cost.

Prestage, John D.

1995-01-01

370

Optical trapping of a single protein.  

PubMed

We experimentally demonstrate the optical trapping of a single bovine serum albumin (BSA) molecule that has a hydrodynamic radius of 3.4 nm, using a double-nanohole in an Au film. The strong optical force in the trap not only stably traps the protein molecule but also unfolds it. The unfolding of the BSA is confirmed by experiments with changing optical power and with changing solution pH. The detection of the trapping event has a signal-to-noise ratio of 33, which shows that the setup is extremely sensitive to detect the presence of a protein, even at the single molecule level. PMID:22171921

Pang, Yuanjie; Gordon, Reuven

2012-01-11

371

s-wave pseudopotential for anisotropic traps  

SciTech Connect

Starting from two identical, interacting particles in an isotropic harmonic trap, we employ first-order perturbation theory to derive the effective s-wave pseudopotential operator for a weakly anisotropic trap. It is shown that such a confinement gives rise to a correction of the s-wave scattering length which is proportional to the square of the ratio of the bare scattering length and the oscillator length. The trap pseudopotential depends on the quantum number of the trapped state, and the effect of a weak anisotropy is dominated by its nearest neighbors. Some implications for experiments with cold bosons in tightly confining potentials are discussed briefly.

Pade, Jochen; Block, Martin; Holthaus, Martin [Institut fuer Physik, Carl von Ossietzky Universitaet, D-26111 Oldenburg (Germany)

2003-12-01

372

Experimental analysis of vortex trapping techniques  

NASA Technical Reports Server (NTRS)

The use of suction to trap a vortex is investigated experimentally. Vortex trapping using a finite sink and cross-flow obstructions is shown to be viable in the case of low-speed flow over a flat plate airfoil. A dual-fence geometry is found to be more efficient than a backward-facing step due to the greater restriction of vortex movement in the streamwise direction. The backward-facing step geometry provides for an increase in the sink strength required for trapping, while the more efficient dual-fence geometry permits the use of a lower suction force for trapping.

Riddle, Todd W.; Tso, Jin; Cummings, Russell M.; Wadcock, Alan J.

1991-01-01

373

Atomic Clock Based On Linear Ion Trap  

NASA Technical Reports Server (NTRS)

Highly stable atomic clock based on excitation and measurement of hyperfine transition in 199Hg+ ions confined in linear quadrupole trap by radio-frequency and static electric fields. Configuration increases stability of clock by enabling use of enough ions to obtain adequate signal while reducing non-thermal component of motion of ions in trapping field, reducing second-order Doppler shift of hyperfine transition. Features described in NPO-17758 "Linear Ion Trap for Atomic Clock." Frequency standard based on hyperfine transition described in NPO-17456, "Trapped-Mercury-Ion Frequency Standard."

Prestage, John D.; Dick, G. John

1992-01-01

374

Interfaces and traps in pentacene field-effect transistor  

NASA Astrophysics Data System (ADS)

The equivalent circuit parameters for a pentacene organic field-effect transistor are determined from low frequency impedance measurements in the dark as well as under light illumination. The source-drain channel impedance parameters are obtained from Bode plot analysis and the deviations at low frequency are mainly due to the contact impedance. The charge accumulation at organic semiconductor-metal interface and dielectric-semiconductor interface is monitored from the response to light as an additional parameter to find out the contributions arising from photovoltaic and photoconductive effects. The shift in threshold voltage is due to the accumulation of photogenerated carriers under source-drain electrodes and at dielectric-semiconductor interface, and also this dominates the carrier transport. The charge carrier trapping at various interfaces and in the semiconductor is estimated from the dc and ac impedance measurements under illumination.

Sangeeth, C. S. Suchand; Stadler, P.; Schaur, S.; Sariciftci, N. S.; Menon, Reghu

2010-12-01

375

Measurement of LET distribution and dose equivalent on board the space shuttle STS-65.  

PubMed

Space radiation dosimetry measurements have been made on board the Space Shuttle STS-65 in the Second International Microgravity Laboratory (IML-2). In these measurements, three kinds of detectors were used; one is a newly developed active detector telescope called "Real-time Radiation Monitoring Device (RRMD)" utilizing silicon semi-conductor detectors and others are conventional detectors of thermoluminescence dosimeters (TLDs) and CR-39 plastic track detectors. Using the RRMD detector, the first attempt of real-time monitoring of space radiation has been achieved successfully for a continuous period of 251.3 h, giving the temporal variations of LET distribution, particle count rates, and rates of absorbed dose and dose equivalent. The RRMD results indicate that a clear enhancement of the number of trapped particles is seen at the South Atlantic Anomaly (SAA) without clear enhancement of dose equivalent, while some daily periodic enhancements of dose equivalent due to high LET particles are seen at the lower geomagnetic cutoff regions for galactic cosmic ray particles (GCRs). Therefore, the main contribution to dose equivalent is seen to be due to GCRs in this low altitude mission (300 km). Also, the dose equivalent rates obtained by TLDs and CR-39 ranged from 146.9 to 165.2 microSv/day and the average quality factors from 1.45 to 1.57 depending on the locations and directions of detectors inside the Space-lab at this highly protected orbit for space radiation with a small inclination (28.5 degrees) and a low altitude (300 km). The LET distributions obtained by two different detectors, RRMD and CR-39, are in good agreement in the region of 15-200 keV/mm and difference of these distributions in the regions of LET < 15 keV/mm and LET > 200 keV/mm can be explained by considering characteristics of CR-39 etched track formation especially for the low LET tracks. PMID:11540526

Hayashi, T; Doke, T; Kikuchi, J; Takeuchi, R; Hasebe, N; Ogura, K; Nagaoka, S; Kato, M; Badhwar, G D

1996-11-01

376

Regulatory match effects on a modified Wisconsin Card Sort Task.  

PubMed

The Wisconsin Card Sorting Task (WCST; Heaton, 1980) is commonly used to assess concept formation and set shifting. Cognitive research suggests that set shifting performance is enhanced by a match between a person's regulatory focus (promotion focus: attempting to earn an entry into a cash drawing; prevention focus: attempting to avoid losing an entry into the drawing) and the task reward structure (gains: attempting to maximize points gained; losses: attempting to minimize points lost). A regulatory match results when attempting to earn an entry by maximizing points or attempting to avoid losing an entry by minimizing losses. We test the hypothesis that performance on a modified WCST is accentuated in younger, healthy participants when there is a match between the global performance incentive and the local task reward structure. As predicted, participants in a match showed better set shifting but equivalent initial concept formation when compared with participants in a mismatch. Furthermore, relative to a baseline control group, mismatch participants were significantly worse at set shifting than were participants in a regulatory match. These results suggest that set shifting performance might be impacted by incentive and task reward factors in ways that have not been considered previously. PMID:20128935

Maddox, W Todd; Filoteo, J Vincent; Glass, Brian D; Markman, Arthur B

2010-03-01

377

A Synthesized Heuristic Task Scheduling Algorithm  

PubMed Central

Aiming at the static task scheduling problems in heterogeneous environment, a heuristic task scheduling algorithm named HCPPEFT is proposed. In task prioritizing phase, there are three levels of priority in the algorithm to choose task. First, the critical tasks have the highest priority, secondly the tasks with longer path to exit task will be selected, and then algorithm will choose tasks with less predecessors to schedule. In resource selection phase, the algorithm is selected task duplication to reduce the interresource communication cost, besides forecasting the impact of an assignment for all children of the current task permits better decisions to be made in selecting resources. The algorithm proposed is compared with STDH, PEFT, and HEFT algorithms through randomly generated graphs and sets of task graphs. The experimental results show that the new algorithm can achieve better scheduling performance. PMID:25254244

Dai, Yanyan; Zhang, Xiangli

2014-01-01

378

Equivalence between free quantum particles and those in harmonic potentials and its application to instantaneous changes  

NASA Astrophysics Data System (ADS)

In quantum physics the free particle and the harmonically trapped particle are arguably the most important systems a physicist needs to know about. It is little known that, mathematically, they are one and the same. This knowledge helps us to understand either from the viewpoint of the other. Here we show that all general time-dependent solutions of the free-particle Schrödinger equation can be mapped to solutions of the Schrödinger equation for harmonic potentials, both the trapping oscillator and the inverted "oscillator". This map is fully invertible and therefore induces an isomorphism between both types of system, they are equivalent. A composition of the map and its inverse allows us to map from one harmonic oscillator to another with a different spring constant and different center position. The map is independent of the state of the system, consisting only of a coordinate transformation and multiplication by a form factor, and can be chosen such that the state is identical in both systems at one point in time. This transition point in time can be chosen freely, the wave function of the particle evolving in time in one system before the transition point can therefore be linked up smoothly with the wave function for the other system and its future evolution after the transition point. Such a cut-and-paste procedure allows us to describe the instantaneous changes of the environment a particle finds itself in. Transitions from free to trapped systems, between harmonic traps of different spring constants or center positions, or, from harmonic binding to repulsive harmonic potentials are straightforwardly modelled. This includes some time-dependent harmonic potentials. The mappings introduced here are computationally more efficient than either state-projection or harmonic oscillator propagator techniques conventionally employed when describing instantaneous (non-adiabatic) changes of a quantum particle's environment.

Steuernagel, Ole

2014-06-01

379

How varying pest and trap densities affect Tribolium castaneum (Coleoptera: Tenebrionidae) capture in pheromone traps  

Technology Transfer Automated Retrieval System (TEKTRAN)

The red flour beetle, Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae), is an important insect pest in food processing facilities. Pheromone trapping is frequently used to monitor red flour beetle populations in structures; however, the optimal trap density and the relationship between trap ...

380

Quantum mechanics in rotating-radio-frequency traps and Penning traps with a quadrupole rotating field  

SciTech Connect

Quantum-mechanical analysis of ion motion in a rotating-radio-frequency (rrf) trap or in a Penning trap with a quadrupole rotating field is carried out. Rrf traps were introduced by Hasegawa and Bollinger [Phys. Rev. A 72, 043404 (2005)]. The classical motion of a single ion in this trap is described by only trigonometric functions, whereas in the conventional linear radio-frequency (rf) traps it is by the Mathieu functions. Because of the simple classical motion in the rrf trap, it is expected that the quantum-mechanical analysis of the rrf traps is also simple compared to that of the linear rf traps. The analysis of Penning traps with a quadrupole rotating field is also possible in a way similar to the rrf traps. As a result, the Hamiltonian in these traps is the same as the two-dimensional harmonic oscillator, and energy levels and wave functions are derived as exact results. In these traps, it is found that one of the vibrational modes in the rotating frame can have negative energy levels, which means that the zero-quantum-number state (''ground'' state) is the highest energy state.

Abe, K.; Hasegawa, T. [Department of Physics, Keio University, Kanagawa 223-8522 (Japan)

2010-03-15

381

A horizontally polarizing liquid trap enhances the tabanid-capturing efficiency of the classic canopy trap.  

PubMed

Host-seeking female tabanid flies, that need mammalian blood for the development of their eggs, can be captured by the classic canopy trap with an elevated shiny black sphere as a luring visual target. The design of more efficient tabanid traps is important for stock-breeders to control tabanids, since these blood-sucking insects can cause severe problems for livestock, especially for horse- and cattle-keepers: reduced meat/milk production in cattle farms, horses cannot be ridden, decreased quality of hides due to biting scars. We show here that male and female tabanids can be caught by a novel, weather-proof liquid-filled black tray laid on the ground, because the strongly and horizontally polarized light reflected from the black liquid surface attracts water-seeking polarotactic tabanids. We performed field experiments to reveal the ideal elevation of the liquid trap and to compare the tabanid-capturing efficiency of three different traps: (1) the classic canopy trap, (2) the new polarization liquid trap, and (3) the combination of the two traps. In field tests, we showed that the combined trap captures 2.4-8.2 times more tabanids than the canopy trap alone. The reason for the larger efficiency of the combined trap is that it captures simultaneously the host-seeking female and the water-seeking male and female tabanids. We suggest supplementing the traditional canopy trap with the new liquid trap in order to enhance the tabanid-capturing efficiency. PMID:23806664

Egri, Á; Blahó, M; Száz, D; Kriska, G; Majer, J; Herczeg, T; Gyurkovszky, M; Farkas, R; Horváth, G

2013-12-01

382

Quantum mechanics in rotating-radio-frequency traps and Penning traps with a quadrupole rotating field  

NASA Astrophysics Data System (ADS)

Quantum-mechanical analysis of ion motion in a rotating-radio-frequency (rrf) trap or in a Penning trap with a quadrupole rotating field is carried out. Rrf traps were introduced by Hasegawa and Bollinger [Phys. Rev. A 72, 043404 (2005)]. The classical motion of a single ion in this trap is described by only trigonometric functions, whereas in the conventional linear radio-frequency (rf) traps it is by the Mathieu functions. Because of the simple classical motion in the rrf trap, it is expected that the quantum-mechanical analysis of the rrf traps is also simple compared to that of the linear rf traps. The analysis of Penning traps with a quadrupole rotating field is also possible in a way similar to the rrf traps. As a result, the Hamiltonian in these traps is the same as the two-dimensional harmonic oscillator, and energy levels and wave functions are derived as exact results. In these traps, it is found that one of the vibrational modes in the rotating frame can have negative energy levels, which means that the zero-quantum-number state (“ground” state) is the highest energy state.

Abe, K.; Hasegawa, T.

2010-03-01

383

Dark matter and the equivalence principle  

NASA Technical Reports Server (NTRS)

If the dark matter in galaxies and clusters is nonbaryonic, it can interact with additional long-range fields that are invisible to experimental tests of the equivalence principle. The astrophysical and cosmological implications of a long-range force coupled only to the dark matter are discussed and rather tight constraints on its strength are found. If the force is repulsive (attractive), the masses of galaxy groups and clusters (and the mean density of the universe inferred from them) have been systematically underestimated (overestimated). Such an interaction also has unusual implications for the growth of large-scale structure.

Frieman, Joshua A.; Gradwohl, Ben-Ami

1991-01-01

384

A tissue-equivalent upper abdominal phantom.  

PubMed

The first prototypes of an abdominal phantom have been constructed. The phantom is intended for eventual use in training diagnostic ultrasound personnel and in demonstrating commercial equipment. It is constructed from plastics believed to be stable and approximately tissue-equivalent at room temperature. Abdominal structures are formed from a dispersion of a polystyrene butadiene plastic in mineral oil. Polyvinyl chloride particles are incorporated to provide the desired attenuation coefficients and scattering levels. B-scans of the phantom produced realistic images, although problems associated with scanning technique and somewhat high phantom attenuation were noted. Very useful phantoms should result from relatively simple improvements in construction techniques. PMID:6632059

Scherzinger, A L; Carson, P L; Clayman, W; Carter, W; Johnson, M L; Rashbaum, C

1983-10-01

385

"Galileo Airborne Test Of Equivalence"-Gate  

NASA Astrophysics Data System (ADS)

A differential Galileo-type mass dropping experiment named GAL was proposed at the University of Pisa in 1986 and completed at CERN in 1992 (Carusotto et al., PRL 69, 1722) in order to test the Equivalence Principle by testing the Universality of Free Fall. The free falling mass was a disk made of two half disks of different composition; a violation of equivalence would produce an angular acceleration of the disk around its symmetry axis, which was measured with a modified Michelson interferometer. GATE -``Galileo Airborne Test of Equivalence'' is a variant of that experiment to be performed in parabolic flight on-board the ``Airbus A300 Zero-g'' aircraft of the European Space Agency (ESA). The main advantages of GATE with respect to GAL are the longer time of free fall and the absence of weight in the final stage of unlocking. The longer time of fall makes the signal stronger (the signal grows quadratically with the time of fall); unlocking at zero-g can significantly reduce spurious angular accelerations of the disk due to inevitable imperfections in the locking/unlocking mechanism, which turned out to be the limiting factor in GAL. A preliminary estimate indicates that GATE should be able to achieve a sensitivity ? ? ? g/g? 10-13, an improvement by about 3 orders of magnitude with respect to GAL and by about 1 order of magnitude with respect to the best result obtained with a slowly rotating torsion balance by the ``Eöt-Wash'' group at the University of Washington. Ground tests of the read-out and of the locking/unlocking disturbances can be carried out prior to the aircraft experiment. Locking/unlocking tests, retrieval tests, as well as tests of the aircraft environment can be performed onboard the Airbus A-300 in preparation for the actual experiment. The GATE experiment can be viewed as an Equivalence Principle test of intermediate sensitivity between torsion balance ground tests (10-12), balloon or micro-satellite (150 kg) tests (GREAT and ? SCOPE: ? 10-15), small-satellite (300 kg) room temperature tests (GG: ? 10-17), large-satellite (1 ton) cryogenic tests (STEP: ? 10-18)

Nobili, A. M.; Unnikrishnan, C. S.; Suresh, D.

386

Gravitational leptogenesis, C, CP and strong equivalence  

E-print Network

The origin of matter-antimatter asymmetry is one of the most important outstanding problems at the interface of particle physics and cosmology. Gravitational leptogenesis (baryogenesis) provides a possible mechanism through explicit couplings of spacetime curvature to appropriate lepton (or baryon) currents. In this paper, the idea that these strong equivalence principle violating interactions could be generated automatically through quantum loop effects in curved spacetime is explored, focusing on the realisation of the discrete symmetries C, CP and CPT which must be broken to induce matter-antimatter asymmetry. The related issue of quantum corrections to the dispersion relation for neutrino propagation in curved spacetime is considered within a fully covariant framework.

J. I. McDonald; Graham M. Shore

2014-11-13

387

The Dissipating Task-Repetition Benefit in Cued Task Switching: Task-Set Decay or Temporal Distinctiveness?  

ERIC Educational Resources Information Center

Decay of task-set activation, as commonly assumed in models of task switching, has been thought to be indexed by manipulating the response-to-cue interval (RCI) in a task-cuing paradigm. We propose an alternative account for RCI effects suggesting that episodic task retrieval is modulated by temporal distinctiveness, which we define as the ratio…

Horoufchin, Himeh; Philipp, Andrea M.; Koch, Iring

2011-01-01

388

Wiring up trapped ions to study aspects of quantum information  

Microsoft Academic Search

There has been much interest in developing methods for transferring quantum information. We discuss a way to transfer quantum information between two trapped ions through a wire. The motion of a trapped ion induces oscillating charges in the trap electrodes. By sending this current to the electrodes of a nearby second trap, the motions of ions in the two traps

N. Daniilidis; T. Lee; R. Clark; S. Narayanan; H. Häffner

2009-01-01

389

Authentic Tasks Online: A synergy among learner, task, and technology  

Microsoft Academic Search

Fostering synergies amongst learner, task, and technology to create innovative and immersive distance learning environments runs counter to the widespread practice of incorporating traditional classroom pedagogical strategies into Web?based delivery of courses. The most widely accepted model of online higher education appears to be one of reductionism, whereby learning management systems facilitate the design of easily digested packets of information,

Jan Herrington; Thomas C. Reeves; Ron Oliver

2006-01-01

390

Authentic Tasks Online: A Synergy among Learner, Task, and Technology  

ERIC Educational Resources Information Center

Fostering synergies amongst "learner," "task," and "technology" to create innovative and immersive distance learning environments runs counter to the widespread practice of incorporating traditional classroom pedagogical strategies into Web-based delivery of courses. The most widely accepted model of online higher education appears to be one of…

Herrington, Jan; Reeves, Thomas C.; Oliver, Ron

2006-01-01

391

Creating external reminders for delayed intentions: Dissociable influence on "task-positive" and "task-negative" brain networks.  

PubMed

Studies of prospective memory and other paradigms requiring participants to remember delayed intentions typically reveal a distinction between lateral and medial rostral prefrontal cortex, whereby the experimental condition yields increased signal in the former region and decreased signal in the latter. These regions comprise nodes of larger "task-positive" and "task-negative" networks that often show opposite patterns of signal change in response to diverse cognitive demands. However, it is not clear to what extent activity in these networks is A) inverse but equivalent, or B) functionally dissociable. In order to address this question, participants performed an "intention-offloading" task while undergoing fMRI. On each trial they remembered a delayed intention, which they had the opportunity to fulfill after a brief filled delay. In one condition they were required to set an external reminder of this intention, while in the other they acted without any external memory aid. Results indicated a clear functional dissociation between the two networks. Compared with a control task with no delayed intention, there was a highly significant reduction in task-negative deactivation when participants used an external memory aid. However, there was no reduction in task-positive activation. These results are consistent with previous evidence that medial rostral prefrontal cortex plays a prominent role in representing the content of delayed intentions, accompanied by a reduction in BOLD signal and potentially increased theta-band oscillatory activity. This role is no longer required once an external reminder has been created. By contrast, lateral rostral prefrontal cortex may play a content-free role, unaffected by the offloading of content into the external environment. PMID:25451474

Landsiedel, Julia; Gilbert, Sam J

2015-01-01

392

The relationship between stimulus equivalence and verbal behavior  

PubMed Central

Despite the apparent similarity between stimulus equivalence and verbal behavior, these phenomena have been described in different terms. With different terminologies for each phenomenon, the precise nature of their relationship is difficult to determine. To explore this relationship, this paper first defines stimulus equivalence using a synthesis of the mathematical definition of the equivalence relation and Sidman and Tailby's (1982) definition. Selected examples of stimulus equivalence are then described as verbal behavior using Skinner's (1957) terminology. The paper then cites instances of verbal behavior that cannot be described as stimulus equivalence and considers whether there are instances of stimulus equivalence that cannot be described as verbal behavior. PMID:22477634

Hall, Genae A.; Chase, Philip N.

1991-01-01

393

Learning an L1-regularized Gaussian Bayesian network in the equivalence class space.  

PubMed

Learning the structure of a graphical model from data is a common task in a wide range of practical applications. In this paper, we focus on Gaussian Bayesian networks, i.e., on continuous data and directed acyclic graphs with a joint probability density of all variables given by a Gaussian. We propose to work in an equivalence class search space, specifically using the k-greedy equivalence search algorithm. This, combined with regularization techniques to guide the structure search, can learn sparse networks close to the one that generated the data. We provide results on some synthetic networks and on modeling the gene network of the two biological pathways regulating the biosynthesis of isoprenoids for the Arabidopsis thaliana plant. PMID:20083459

Vidaurre, Diego; Bielza, Concha; Larrañaga, Pedro

2010-10-01

394

Establishing an effective dose equivalent monitoring program for a commercial nuclear power station  

NASA Astrophysics Data System (ADS)

The purpose of this thesis is to determine whether monitoring personnel with multiple dosimeter badges to determine effective dose equivalent (EDE) is both acceptable to the Nuclear Regulatory Commission (NRC) and practical for the nuclear power industry. Until now, most nuclear power plants have used a single dosimeter or occasionally multiple dosimeters to monitor the "deep dose equivalent (DDE)" as defined by the International Commission on Radiological Units (ICRU). The measurement of EDE, to replace DDE, is now deemed by international and regulatory agencies to better approximate a worker's dose related to long-term risks of occupational radiation exposure. The definition of DDE, and the formulation of EDE for use as a new indicator of occupational exposure, are presented in this thesis. Radiation exposure measurements using multiple dosimeters on each worker for certain tasks were collected for this thesis on workers at a Dominion/Virginia Company nuclear power plant. These multiple dosimeter measurements have been examined to determine how such a new personnel monitoring system compares to the former one at the Dominion plant, in which only one dosimeter reading was used predominately to calculated deep dose equivalent. This is based on the assumption that most workers were exposed to uniform radiation fields and that the single dosimeter reading was representative of the highest average exposure for the worker's task. These multiple dosimetry measurements show that it is both feasible and advantageous to provide such dosimetry in situations where exposures may be non-uniform and significant enough to approach yearly exposure limits in a single day, such as in the tasks required during refueling outages.

Thompson, Barbara Jane

395

Cryptography, quantum computation and trapped ions  

Microsoft Academic Search

The significance of quantum computation for cryptography is discussed. Following a brief survey of the requirements for quantum computational hardware, an overview of the ion trap quantum computation project at Los Alamos is presented. The physical limitations to quantum computation with trapped ions are analyzed and an assessment of the computational potential of the technology is made.

R. J. Hughes; Richard J

1998-01-01

396

Actin filament mechanics in the laser trap  

Microsoft Academic Search

Summary Numerous biological processes, including muscular contraction, depend upon the mechanical properties of actin filaments. One such property is resistance to bending (flexural rigidity, EI). To estimate EI, we attached the ends of fluorescently labelled actin filaments to two microsphere 'handles' captured in independent laser traps. The positions of the traps were manipulated to apply a range of tensions (0-8

D. E. D UPUIS; D. M. W ARSHAW

1997-01-01

397

Black holes as trapping horizons Eric Gourgoulhon  

E-print Network

Black holes as trapping horizons Eric Gourgoulhon Laboratoire Univers et Th´eories (LUTH) CNRS://www.luth.obspm.fr/~luthier/gourgoulhon/ Centrum Astronomiczne im. M. Kopernika Warsaw, Poland 17 November 2008 Eric Gourgoulhon (LUTH) Black holes as trapping horizons CAMK, Warsaw, 17 Nov. 2008 1 / 36 #12;Plan 1 Local approaches to black holes 2 Viscous

Gourgoulhon, Eric

398

FOAM PREVENTION IN PURGE AND TRAP ANALYSIS  

EPA Science Inventory

Volatile organics are often separated from water samples by bubbling an inert gas through the water and collecting the organics on a sorbent trap, a technique known as purge and trap. Unfortunately, during the analysis of many water samples, foam can climb through the apparatus a...

399

Heterogeneous firms, productivity and poverty traps  

Microsoft Academic Search

We present a model of endogenous total factor productivity which generates poverty traps. We obtain multiple steady-state equilibria for an arbitrarily small degree of increasing returns to scale. While the most productive firms operate across all the steady states, in a poverty trap less productive firms operate as well. This results in lower average firm productivity and lower total factor

Levon Barseghyan; Riccardo DiCecio

2006-01-01

400

Trapped radiation belts of Saturn - First look  

Microsoft Academic Search

Data on the magnetosphere of Saturn obtained with the trapped radiation detector package on board the Pioneer 11 spacecraft is reported. Radiation belt profiles determined by the trapped radiation detectors on Pioneer 10 and 11 indicate that Saturn's magnetosphere is intermediate in size between those of the earth and Jupiter, with particle intensities similar to those of the earth. The

W. Fillius; W. H. Ip; C. E. McIlwain

1980-01-01

401

Cryptography, quantum computation and trapped ions  

SciTech Connect

The significance of quantum computation for cryptography is discussed. Following a brief survey of the requirements for quantum computational hardware, an overview of the ion trap quantum computation project at Los Alamos is presented. The physical limitations to quantum computation with trapped ions are analyzed and an assessment of the computational potential of the technology is made.

Hughes, Richard J.

1998-03-01

402

49 CFR 236.728 - Circuit, trap.  

Code of Federal Regulations, 2010 CFR

... 2010-10-01 2010-10-01 false Circuit, trap. 236.728 Section 236.728 Transportation...AND APPLIANCES Definitions § 236.728 Circuit, trap. A term applied to a circuit used where it is desirable to provide a...

2010-10-01

403

49 CFR 236.728 - Circuit, trap.  

Code of Federal Regulations, 2012 CFR

... 2012-10-01 2012-10-01 false Circuit, trap. 236.728 Section 236.728 Transportation...AND APPLIANCES Definitions § 236.728 Circuit, trap. A term applied to a circuit used where it is desirable to provide a...

2012-10-01

404

49 CFR 236.728 - Circuit, trap.  

Code of Federal Regulations, 2013 CFR

... 2013-10-01 2013-10-01 false Circuit, trap. 236.728 Section 236.728 Transportation...AND APPLIANCES Definitions § 236.728 Circuit, trap. A term applied to a circuit used where it is desirable to provide a...

2013-10-01

405

49 CFR 236.728 - Circuit, trap.  

Code of Federal Regulations, 2011 CFR

... 2011-10-01 2011-10-01 false Circuit, trap. 236.728 Section 236.728 Transportation...AND APPLIANCES Definitions § 236.728 Circuit, trap. A term applied to a circuit used where it is desirable to provide a...

2011-10-01

406

ADMINISTRATIVE APPEALS A TRAP FOR THE UNWARY  

E-print Network

ADMINISTRATIVE APPEALS A TRAP FOR THE UNWARY An administrative appeal from an order of the Nebraska, can be a trap for the unwary lawyer. THE QUANDRY There is more than one method to appeal or contest the Appeal. (a) Neb. Rev. Stat. § 46-750 provides in pertinent part Any person aggrieved by any order

Nebraska-Lincoln, University of

407

Single Trap Profiling by Charge Pumping  

Microsoft Academic Search

We demonstrate that the CP characteristic of a single trap can be measured in relatively large MOSFETs or even in arrays of MOSFETs with common gates, common sources and separated drain contacts where the total quantity of interface traps can be as high as several thousands. The influence of CP parameters is also demonstrated. The possibility to use these results

S. Okhonin; V. Meyer; A. Ils; P. Fazan; L. Risch; F. Hoffman

2000-01-01

408

Trapping of propelled colloidal particles  

E-print Network

A trapping mechanism for propelled colloidal particles based on an inhomogeneous drive is presented and studied analytically as well as by computer simulations. In experiments this method can be realized using photophoretic Janus particles driven by a light source, which shines through a shading mask and leads to an accumulation of the particles in the shaded part. In an overdamped scenario for colloidal particles, valid for self-propelled particles like microswimmers, the shading causes an inhomogeneous diffusion constant which results in accumulation. For propelled colloidal particles with a finite mass inertia causes a finite penetration depth of particles impinging from the illuminated part of the system into the shaded part, which increases accumulation.

Martin P. Magiera; Lothar Brendel

2014-09-26

409

Masonry: Task Analyses. Competency-Based Education.  

ERIC Educational Resources Information Center

These task analyses are designed to be used in combination with the "Trade and Industrial Education Service Area Resource" in order to implement competency-based education in the masonry program in Virginia. The task analysis document contains the task inventory, suggested task sequence lists, and content outlines for the secondary courses Masonry…

Henrico County Public Schools, Glen Allen, VA. Virginia Vocational Curriculum Center.

410

An architecture for intelligent task interruption  

NASA Technical Reports Server (NTRS)

In the design of real time systems the capability for task interruption is often considered essential. The problem of task interruption in knowledge-based domains is examined. It is proposed that task interruption can be often avoided by using appropriate functional architectures and knowledge engineering principles. Situations for which task interruption is indispensable, a preliminary architecture based on priority hierarchies is described.

Sharma, D. D.; Narayan, Srini

1990-01-01

411

Trapping of Ultracold Polar Molecules with a Thin-Wire Electrostatic Trap  

SciTech Connect

We describe the realization of a dc electric-field trap for ultracold polar molecules, the thin-wire electrostatic trap (TWIST). The thin wires that form the electrodes of the TWIST allow us to superimpose the trap onto a magneto-optical trap (MOT). In our experiment, ultracold polar NaCs molecules in their electronic ground state are created in the MOT via photoassociation, achieving a continuous accumulation in the TWIST of molecules in low-field seeking states. Initial measurements show that the TWIST trap lifetime is limited only by the background pressure in the chamber.

Kleinert, J.; Haimberger, C.; Zabawa, P. J.; Bigelow, N. P. [Department of Physics and Astronomy, and The Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14627 (United States)

2007-10-05

412

Low temperature delayed recombination and trap tunneling.  

PubMed

Delayed recombination of charge carriers at an activator is a significant problem for fast scintillators and is usually associated with thermal effects. However, experimental results have shown that this phenomenon can occur even at the lowest temperatures. We here provide evidence in support of the idea that this is due to quantum tunneling between activator and nearby traps, and provide analytic estimates relating the energy levels and locations of those traps to the observed delayed recombination. Several calculations are devoted to showing that deviations from the simplest estimates in fact do not occur. Moreover, these estimates are consistent with lower dimensional numerical calculations for a physically significant range of trap distances. In two examples involving the activator Pr, the formulas developed are used to give the locations of traps based on likely values of trap energy depth. PMID:25629233

Mihóková, E; Schulman, L S

2015-02-25

413

Ion Trap in a Semiconductor Chip  

E-print Network

The electromagnetic manipulation of isolated atoms has led to many advances in physics, from laser cooling and Bose-Einstein condensation of cold gases to the precise quantum control of individual atomic ion. Work on miniaturizing electromagnetic traps to the micrometer scale promises even higher levels of control and reliability. Compared with 'chip traps' for confining neutral atoms, ion traps with similar dimensions and power dissipation offer much higher confinement forces and allow unparalleled control at the single-atom level. Moreover, ion microtraps are of great interest in the development of miniature mass spectrometer arrays, compact atomic clocks, and most notably, large scale quantum information processors. Here we report the operation of a micrometer-scale ion trap, fabricated on a monolithic chip using semiconductor micro-electromechanical systems (MEMS) technology. We confine, laser cool, and measure heating of a single 111Cd+ ion in an integrated radiofrequency trap etched from a doped gallium arsenide (GaAs) heterostructure.

D. Stick; W. K. Hensinger; S. Olmschenk; M. J. Madsen; K. Schwab; C. Monroe

2006-01-09

414

A dynamical model for the Utricularia trap  

PubMed Central

We propose a model that captures the dynamics of a carnivorous plant, Utricularia inflata. This plant possesses tiny traps for capturing small aquatic animals. Glands pump water out of the trap, yielding a negative pressure difference between the plant and its surroundings. The trap door is set into a meta-stable state and opens quickly as an extra pressure is generated by the displacement of a potential prey. As the door opens, the pressure difference sucks the animal into the trap. We write an ODE model that captures all the physics at play. We show that the dynamics of the plant is quite similar to neuronal dynamics and we analyse the effect of a white noise on the dynamics of the trap. PMID:22859569

Llorens, Coraline; Argentina, Médéric; Bouret, Yann; Marmottant, Philippe; Vincent, Olivier

2012-01-01

415

Trapping atoms using nanoscale quantum vacuum forces  

PubMed Central

Quantum vacuum forces dictate the interaction between individual atoms and dielectric surfaces at nanoscale distances. For example, their large strengths typically overwhelm externally applied forces, which makes it challenging to controllably interface cold atoms with nearby nanophotonic systems. Here we theoretically show that it is possible to tailor the vacuum forces themselves to provide strong trapping potentials. Our proposed trapping scheme takes advantage of the attractive ground-state potential and adiabatic dressing with an excited state whose potential is engineered to be resonantly enhanced and repulsive. This procedure yields a strong metastable trap, with the fraction of excited-state population scaling inversely with the quality factor of the resonance of the dielectric structure. We analyse realistic limitations to the trap lifetime and discuss possible applications that might emerge from the large trap depths and nanoscale confinement. PMID:25008119

Chang, D. E.; Sinha, K.; Taylor, J. M.; Kimble, H. J.

2014-01-01

416

New vanadium trap proven in commercial trials  

SciTech Connect

A vanadium trap technology called RV4+ has demonstrated in a variety of commercial fluid catalytic cracking (FCC) units its ability to reduce vanadium on equilibrium catalyst by more than 20%. Reducing vanadium loading increases microactivity and zeolite surface area retention, confirming that RV4+ protects zeolites from vanadium deactivation. Sulfur competition had prevented some previous traps from working commercially, but was not a factor with the new trap. The technology can save refiners millions of dollars per year in catalyst costs, or allow them to process feeds containing higher vanadium concentrations. The paper discusses vanadium traps, deactivation mechanism, history of traps, vanadium mobility, intraparticle mobility, interparticle mobility, measuring performance, commercial results, sulfur competition, and economic value.

Dougan, T.J. (Grace Davison, Baltimore, MD (United States)); Alkemade, U.; Lakhanpal, B. (Grace Davison, Worms (Germany)); Boock, L.T. (Grace Davison, Columbia, MD (United States))

1994-09-26

417

Magnetic Trapping of Cold Bromine Atoms  

E-print Network

Magnetic trapping of bromine atoms at temperatures in the milliKelvin regime is demonstrated for the first time. The atoms are produced by photodissociation of Br$_2$ molecules in a molecular beam. The lab-frame velocity of Br atoms is controlled by the wavelength and polarization of the photodissociation laser. Careful selection of the wavelength results in one of the pair of atoms having sufficient velocity to exactly cancel that of the parent molecule, and it remains stationary in the lab frame. A trap is formed at the null point between two opposing neodymium permanent magnets. Dissociation of molecules at the field minimum results in the slowest fraction of photofragments remaining trapped. After the ballistic escape of the fastest atoms, the trapped slow atoms are only lost by elastic collisions with the chamber background gas. The measured loss rate is consistent with estimates of the total cross section for only those collisions transferring sufficient kinetic energy to overcome the trapping potential...

Rennick, C J; Doherty, W G; Softley, T P

2014-01-01

418

Magneto-optical trap for thulium atoms  

SciTech Connect

Thulium atoms are trapped in a magneto-optical trap using a strong transition at 410 nm with a small branching ratio. We trap up to 7x10{sup 4} atoms at a temperature of 0.8(2) mK after deceleration in a 40-cm-long Zeeman slower. Optical leaks from the cooling cycle influence the lifetime of atoms in the magneto-optical trap which varies between 0.3 and 1.5 s in our experiments. The lower limit for the leaking rate from the upper cooling level is measured to be 22(6) s{sup -1}. The repumping laser transferring the atomic population out of the F=3 hyperfine ground-state sublevel gives a 30% increase for the lifetime and the number of atoms in the trap.

Sukachev, D.; Sokolov, A.; Chebakov, K.; Akimov, A.; Kanorsky, S.; Kolachevsky, N.; Sorokin, V. [P.N. Lebedev Physical Institute, Leninsky Prospekt 53, 119991 Moscow (Russian Federation)

2010-07-15

419

Magnetic trapping of cold bromine atoms.  

PubMed

Magnetic trapping of bromine atoms at temperatures in the millikelvin regime is demonstrated for the first time. The atoms are produced by photodissociation of Br2 molecules in a molecular beam. The lab-frame velocity of Br atoms is controlled by the wavelength and polarization of the photodissociation laser. Careful selection of the wavelength results in one of the pair of atoms having sufficient velocity to exactly cancel that of the parent molecule, and it remains stationary in the lab frame. A trap is formed at the null point between two opposing neodymium permanent magnets. Dissociation of molecules at the field minimum results in the slowest fraction of photofragments remaining trapped. After the ballistic escape of the fastest atoms, the trapped slow atoms are lost only by elastic collisions with the chamber background gas. The measured loss rate is consistent with estimates of the total cross section for only those collisions transferring sufficient kinetic energy to overcome the trapping potential. PMID:24484005

Rennick, C J; Lam, J; Doherty, W G; Softley, T P

2014-01-17

420

Task Analysis Inventories. Series II.  

ERIC Educational Resources Information Center

This second in a series of task analysis inventories contains checklists of work performed in twenty-two occupations. Each inventory is a comprehensive list of work activities, responsibilities, educational courses, machines, tools, equipment, and work aids used and the products produced or services rendered in a designated occupational area. The…

Wesson, Carl E.

421

Task Group 9 Update (Presentation)  

SciTech Connect

This presentation is a brief update of IEC TC82 QA Task Force, Group 9. Presented is an outline of the recently submitted New Work Item Proposal (NWIP) for a Comparative Thermal Cycling Test for CPV Modules to Differentiate Thermal Fatigue Durability.

Bosco, N.

2014-04-01

422

Security tasks are highly interdependent.  

E-print Network

· Academic freedom · Distribution of IT management · Tight schedules · Security not part of the core businessMotivation Security tasks are highly interdependent. To improve security tools, we need to understand how security practitioners collaborate in their organizations. Security practitioners in context

423

Muon Task Force Valeri Lebedev  

E-print Network

Possible experiments Next generation (g-2) if motivated by next round (theory, LHC) Next generation -to of experiments High energy, small repetition rate (~10-100 Hz, fast extraction from ring) (g-2) Small energyMuon Task Force Valeri Lebedev Sergei Striganov and Vitaly Pronskikh Contents Introduction Basics

McDonald, Kirk

424

Incidental Learning and Task Boundaries  

ERIC Educational Resources Information Center

For skill learning processes to be effective, they must encode associations that are inherent to the current task and avoid those that are spurious or particular to training conditions so that learning can transfer to novel situations. Some everyday contexts even require grouped responding to simultaneously presented stimuli. Here we test whether…

Freedberg, Michael; Wagschal, Tana T.; Hazeltine, Eliot

2014-01-01

425

Safely Delegating Data Mining Tasks  

Microsoft Academic Search

Data mining is playing an important role in decision making for business activities and governmental ad- ministration. Since many organizations or their di- visions do not possess the in-house expertise and in- frastructure for data mining, it is beneficial to dele- gate data mining tasks to external service providers. However, the organizations or divisions may lose of private information during

Ling Qiu; Kok-leong Ong; Siu Man Lui

2006-01-01

426

Task Variability and Interlanguage Use.  

ERIC Educational Resources Information Center

Investigates the role of elicitation tasks on the linguistic performance of Persian learners learning English in a nonnative speaking environment. The purpose is to investigate whether learners' interlanguage ranges along a continuum or whether it shifts between two opposing poles of monitored/unmonitored varieties. (29 references)

Sajjadi, Samad; Tahririan, M. H.

1992-01-01

427

Interacting Tasks Part I. Preliminaries  

E-print Network

CPU, BIG DATA et's tackle the N-body zombie program from Chapter 7 and develop a cluster parallel to implement that pattern simply by calling the masterFor() and workerFor() methods. In the zombie program there were no data structures that had to be shared among the tasks of the job. In the zombie program

Kaminsky, Alan

428

Tasks Ahead for Indian Education.  

ERIC Educational Resources Information Center

Reviews past accomplishments and remaining tasks in Indian education with particular emphasis on the production of technical and professional personnel to match the nation's labor needs and the spread of education to three previously disadvantaged groups: rural populations, women, and the scheduled castes and tribes. (SJL)

Yadav, R. K.

1980-01-01

429

Precautions regarding Nonword Repetition Tasks  

ERIC Educational Resources Information Center

Using nonword repetition tasks as an experimental approach with both adults and children has become quite common in the past 10 to 15 years for studying lexical learning and phonological processing (e.g., Bailey & Hahn, 2001; Gathercole, Frankish, Pickering & Peaker, 1998; Munson, Edwards, & Beckman, 2005; Storkel, 2001; Vitevich & Luce, 2005). In…

Smith, Bruce

2006-01-01

430

How social are task representations?  

Microsoft Academic Search

The classical Simon effect shows that actions are carried out faster if they spatially correspond to the stimulus signaling them. Recent studies revealed that this is the case even when the two actions are carried out by different people; this finding has been taken to imply that task representations are socially shared. In work described here, we found that the

B. Hommel; L. S. Colzato; Wildenberg van den W. P. M

2009-01-01

431

AUTONOMOUS ROBOT IN AGRICULTURE TASKS  

Microsoft Academic Search

Present work deals with the automation of a low cost commercial lawnmower to perform unmanned precision agriculture tasks such are the spraying of pesticides. To this aim the vehicle has been endowed with a set of additional subsystems and sensors to perform remote motion control and to obtain relative and absolute location in the field. The equipment integrated is composed

M. C. GARCIA-ALEGRE; A. RIBEIRO; L. GARCIA-PEREZ; R. MARTINEZ; A. POZO-RUZ

432

Supervisor Personality and Task Preference.  

ERIC Educational Resources Information Center

The purpose of this study was to determine the relationship between an instructional supervisor's behavior and personality. A survey instrument was used to determine how frequently 56 supervisors preferred to perform and actually performed 10 major supervisory tasks. The Rokeach Dogmatism Scale was used to measure the individual's belief-disbelief…

Mikkelsen, Vincent P.; Joyner, Wilton G.

433

Multi-Robot Task Allocation for Performing Cooperative Foraging Tasks in an Initially Unknown Environment  

Microsoft Academic Search

\\u000a We consider the problem of multi-robot task allocation (MRTA) by a set of robots that are deployed in an initially unknown\\u000a environment to perform foraging tasks. The location of each task has to be discovered by each robot through searching in the\\u000a environment. Each task also requires multiple robots to share the task’s execution to complete the task. We discuss

Prithviraj Dasgupta

434

The habitats exploited and the species trapped in a Caribbean island trap fishery  

USGS Publications Warehouse

We visually observed fish traps in situ to identify the habitats exploited by the U.S. Virgin Islands fishery and to document species composition and abundance in traps by habitat. Fishers set more traps in algal plains than in any other habitat around St. John. Coral reefs, traditionally targeted by fishers, accounted for only 16% of traps. Traps in algal plain contained the highest number of fishes per trap and the greatest numbers of preferred food species. Traps on coral reefs contained the most species, 41 of the 59 taxa observed in the study. Acanthurus coeruleus was the most abundant species and Acanthuridae the most abundant family observed in traps. Piscivore numbers were low and few serranids were observed. Traps in algal plain contained the most fishes as a result of: ecological changes such as shifts in habitat use, mobility of species and degradation of nearshore habitat (fishery independent); and, catchability of fishes and long-term heavy fishing pressure (fishery dependent). The low number of serranids per trap, dominance of the piscivore guild by a small benthic predator, Epinephelus guttatus, and dominance of trap contents overall by a small, fast-growing species of a lower trophic guild, Acanthurus coeruleus, all point to years of intense fishing pressure.

Garrison, V.H.; Rogers, C.S.; Beets, J.; Friedlander, A.M.

2004-01-01

435

Gene Trapping Using Gal4 in Zebrafish  

PubMed Central

Large clutch size and external development of optically transparent embryos make zebrafish an exceptional vertebrate model system for in vivo insertional mutagenesis using fluorescent reporters to tag expression of mutated genes. Several laboratories have constructed and tested enhancer- and gene-trap vectors in zebrafish, using fluorescent proteins, Gal4- and lexA- based transcriptional activators as reporters 1-7. These vectors had two potential drawbacks: suboptimal stringency (e.g. lack of ability to differentiate between enhancer- and gene-trap events) and low mutagenicity (e.g. integrations into genes rarely produced null alleles). Gene Breaking Transposon (GBTs) were developed to address these drawbacks 8-10. We have modified one of the first GBT vectors, GBT-R15, for use with Gal4-VP16 as the primary gene trap reporter and added UAS:eGFP as the secondary reporter for direct detection of gene trap events. Application of Gal4-VP16 as the primary gene trap reporter provides two main advantages. First, it increases sensitivity for genes expressed at low expression levels. Second, it enables researchers to use gene trap lines as Gal4 drivers to direct expression of other transgenes in very specific tissues. This is especially pertinent for genes with non-essential or redundant functions, where gene trap integration may not result in overt phenotypes. The disadvantage of using Gal4-VP16 as the primary gene trap reporter is that genes coding for proteins with N-terminal signal sequences are not amenable to trapping, as the resulting Gal4-VP16 fusion proteins are unlikely to be able to enter the nucleus and activate transcription. Importantly, the use of Gal4-VP16 does not pre-select for nuclear proteins: we recovered gene trap mutations in genes encoding proteins which function in the nucleus, the cytoplasm and the plasma membrane. PMID:24121167

Balciuniene, Jorune; Balciunas, Darius

2013-01-01

436

21 CFR 868.5995 - Tee drain (water trap).  

Code of Federal Regulations, 2012 CFR

...trap). (a) Identification. A tee drain (water trap) is a device intended to trap and drain water that collects in ventilator tubing during respiratory therapy, thereby preventing an increase in breathing resistance. (b) Classification....

2012-04-01

437

21 CFR 868.5995 - Tee drain (water trap).  

Code of Federal Regulations, 2011 CFR

...trap). (a) Identification. A tee drain (water trap) is a device intended to trap and drain water that collects in ventilator tubing during respiratory therapy, thereby preventing an increase in breathing resistance. (b) Classification....

2011-04-01

438

21 CFR 868.5995 - Tee drain (water trap).  

...trap). (a) Identification. A tee drain (water trap) is a device intended to trap and drain water that collects in ventilator tubing during respiratory therapy, thereby preventing an increase in breathing resistance. (b) Classification....

2014-04-01

439

Trap-related injuries to gray wolves in Minnesota  

USGS Publications Warehouse

Gray wolves (Canis lupus) captured in traps with toothed jaws offset 1.8 cm incurred fewer injuries than those captured in 3 other types of steel traps. Few wolves seriously damaged canine or carnassial teeth while in traps.

Kuehn, D.W.; Fuller, T.K.; Mech, L.D.; Paul, W.J.; Fritts, S.H.; Berg, W.E.

1986-01-01

440

30 CFR 90.206 - Approved sampling devices; equivalent concentrations.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 2010-07-01 false Approved sampling devices; equivalent concentrations. 90...EVIDENCE OF THE DEVELOPMENT OF PNEUMOCONIOSIS Sampling Procedures § 90.206 Approved sampling devices; equivalent concentrations....

2010-07-01

441

30 CFR 71.206 - Approved sampling devices; equivalent concentrations.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 2010-07-01 false Approved sampling devices; equivalent concentrations. 71...SURFACE WORK AREAS OF UNDERGROUND COAL MINES Sampling Procedures § 71.206 Approved sampling devices; equivalent concentrations....

2010-07-01

442

Elementary equivalence of Chevalley groups over local rings  

SciTech Connect

It is proved that (elementary) Chevalley groups over local rings with invertible 2 are elementarily equivalent if and only if their types and weight lattices coincide and the initial rings are elementarily equivalent. Bibliography: 25 titles.

Bunina, Elena I [M. V. Lomonosov Moscow State University, Faculty of Mechanics and Mathematics, Moscow (Russian Federation)

2010-05-11

443

Dose rate, dose-equivalent rate, and quality factor in SLS-1  

NASA Technical Reports Server (NTRS)

A tissue-equivalent proportional counter (TEPC) sensitive to the lineal energy range of 0.26-300 keV micrometer-1 was flown on STS-40 (39 degrees x 278 km x 296 km) inside the Spacelab. This instrument was previously flown on STS-31 but was modified to provide a finer resolution at lower lineal energies to better map the South Atlantic Anomaly (SAA) protons. The instrument was turned on 6 June 1991, and operated for 7470 min (124.5 h). The flight duration was characterized by a very large number of X-ray solar flares and enhanced magnetic field fluctuations; however, no significant dose from the solar particles was measured at the location of this instrument. The flight data can be separated into trapped and galactic cosmic radiation parts. The dose rate, dose-equivalent rate and quality factor for trapped radiation were 4.21 +/- 0.03 mrad day-1, 7.72 +/- 0.05 mrem day-1, and 1.83 +/- 0.1, respectively. The dose rate, dose-equivalent rate, and quality factor for galactic cosmic radiation were 5.34 +/- 0.03 mrad day-1, 14.63 +/- 0.06 mrem day-1, and 2.74 +/- 0.1, respectively. The overall quality factor for the flight was 2.38. The dose from the GCR is higher than from SAA protons because of the high inclination and low altitude of this flight. The AP8MAX model of the trapped radiation gives a dose rate of 2.43 mrad day-1 and a quality factor of 1.77. The CREME solar maximum model of galactic cosmic radiation gives a dose rate of 2.54 mrad day-1 and a quality factor of 2.91. Thus the AP8MAX model underestimates the dose by a factor of 1.8 whereas the CREME model leads to an underestimation of the dose by a factor of 2. A comparison of the LET spectra using the AP8MAX model and galactic cosmic radiation transport codes shows only a qualitative agreement.

Badhwar, G. D.; Braby, L. A.; Cucinotta, F. A.; Atwell, W.

1992-01-01

444

A method for trapping breeding adult American Oystercatchers  

USGS Publications Warehouse

We present an efficient and effective method for trapping adult, breeding American Oystercatchers (Haematopus palliatus) that minimizes disturbance to nesting birds and the risk of trapping injuries. We used a remote controlled mechanical decoy to lure territorial adults to a leg-hold noose-mat trap. We trapped 25 birds over two seasons and were successful on 54% of our trapping attempts in 2003. We only trapped birds before the breeding season or between nesting attempts to reduce nest-site disturbance.

McGowan, C.P.; Simons, T.R.

2005-01-01

445

Equivalent formulations of “the equation of life”  

NASA Astrophysics Data System (ADS)

Motivated by progress in theoretical biology a recent proposal on a general and quantitative dynamical framework for nonequilibrium processes and dynamics of complex systems is briefly reviewed. It is nothing but the evolutionary process discovered by Charles Darwin and Alfred Wallace. Such general and structured dynamics may be tentatively named “the equation of life”. Three equivalent formulations are discussed, and it is also pointed out that such a quantitative dynamical framework leads naturally to the powerful Boltzmann-Gibbs distribution and the second law in physics. In this way, the equation of life provides a logically consistent foundation for thermodynamics. This view clarifies a particular outstanding problem and further suggests a unifying principle for physics and biology.

Ao, Ping

2014-07-01

446

Noise-equivalent sensitivity of photoacoustics  

PubMed Central

Abstract. The fundamental limitations of photoacoustic microscopy for detecting optically absorbing molecules are investigated both theoretically and experimentally. We experimentally demonstrate noise-equivalent detection sensitivities of 160,000 methylene blue molecules (270 zeptomol or 2.7×10?19??mol) and 86,000 oxygenated hemoglobin molecules (140 zeptomol) using narrowband continuous-wave photoacoustics. The ultimate sensitivity of photoacoustics is fundamentally limited by thermal noise, which can present in the acoustic detection system as well as in the medium itself. Under the optimized conditions described herein and using commercially available detectors, photoacoustic microscopy can detect as few as 100s of oxygenated hemoglobin molecules. Realizable improvements to the detector may enable single molecule detection of select molecules. PMID:24026425

Winkler, Amy M.; Maslov, Konstantin; Wang, Lihong V.

2013-01-01

447

Equivalence of the Einstein and Jordan frames  

NASA Astrophysics Data System (ADS)

No experiment can measure an absolute scale: every dimensionful quantity has to be compared to some fixed unit scale in order to be measured, and thus only dimensionless quantities are really physical. The Einstein and Jordan frames are related by a conformal transformation of the metric, which amounts to rescaling all length scales. Since the absolute scale cannot be measured, both frames describe the same physics and are equivalent. In this article we make this explicit by rewriting the action in terms of dimensionless variables, which are invariant under a conformal transformation. For definitiveness, we concentrate on the action of Higgs inflation, but the results can easily be generalized. In addition, we show that the action for f (R ) gravity, which includes Starobinsky inflation, can be written in a frame-independent form.

Postma, Marieke; Volponi, Marco

2014-11-01

448

Snow water equivalent determination by microwave radiometry  

NASA Technical Reports Server (NTRS)

One of the most important parameters for accurate snowmelt runoff prediction is snow water equivalent (SWE) which is contentionally monitored using observations made at widely scattered points in or around specific watersheds. Remote sensors which provide data with better spatial and temporal coverage can be used to improve the SWE estimates. Microwave radiation, which can penetrate through a snowpack, may be used to infer the SWE. Calculations made from a microscopic scattering model were used to simulate the effect of varying SWE on the microwave brightness temperature. Data obtained from truck mounted, airborne and spaceborne systems from various test sites were studied. The simulated SWE compares favorable with the measured SWE. In addition, whether the underlying soil is frozen or thawed can be discriminated successfully on the basis of the polarization of the microwave radiation.

Chang, A. T. C.; Foster, J. L.; Hall, D. K.; Rango, A.; Hartline, B. K.

1981-01-01

449

Multiband signal reconstruction for random equivalent sampling.  

PubMed

The random equivalent sampling (RES) is a sampling approach that can be applied to capture high speed repetitive signals with a sampling rate that is much lower than the Nyquist rate. However, the uneven random distribution of the time interval between the excitation pulse and the signal degrades the signal reconstruction performance. For sparse multiband signal sampling, the compressed sensing (CS) based signal reconstruction algorithm can tease out the band supports with overwhelming probability and reduce the impact of uneven random distribution in RES. In this paper, the mathematical model of RES behavior is constructed in the frequency domain. Based on the constructed mathematical model, the band supports of signal can be determined. Experimental results demonstrate that, for a signal with unknown sparse multiband, the proposed CS-based signal reconstruction algorithm is feasible, and the CS reconstruction algorithm outperforms the traditional RES signal reconstruction method. PMID:25362458

Zhao, Y J; Liu, C J

2014-10-01

450

Multiband signal reconstruction for random equivalent sampling  

NASA Astrophysics Data System (ADS)

The random equivalent sampling (RES) is a sampling approach that can be applied to capture high speed repetitive signals with a sampling rate that is much lower than the Nyquist rate. However, the uneven random distribution of the time interval between the excitation pulse and the signal degrades the signal reconstruction performance. For sparse multiband signal sampling, the compressed sensing (CS) based signal reconstruction algorithm can tease out the band supports with overwhelming probability and reduce the impact of uneven random distribution in RES. In this paper, the mathematical model of RES behavior is constructed in the frequency domain. Based on the constructed mathematical model, the band supports of signal can be determined. Experimental results demonstrate that, for a signal with unknown sparse multiband, the proposed CS-based signal reconstruction algorithm is feasible, and the CS reconstruction algorithm outperforms the traditional RES signal reconstruction method.

Zhao, Y. J.; Liu, C. J.

2014-10-01

451

New formulations for dual equivalent actions  

E-print Network

New actions in D=2 and D=3 are proposed that are dual equivalent to known theories displaying well defined chirality and helicity, respectively, along with a new interpolating action that maps continuously through the original dualities. The new chiral action in D=2 is a second-order theory displaying the chiral constraint dynamically while in D=3 the helicity constraint is imposed a la Siegel. The resulting theories introduce new versions of the Hull noton to take care of the symmetry aspects of the original models. The new interpolating formulation is then re-examined as a condensed phase for the discussion of duality under the light of the dual mechanisms -- Julia-Toulouse and Higgs -- establishing new interpolating actions in the dilute phase, according to these mechanisms.

E. M. C. Abreu; A. Calil; L. S. Grigorio; M. S. Guimaraes; C. Wotzasek

2007-11-30

452

Equivalence principle implications of modified gravity models  

NASA Astrophysics Data System (ADS)

Theories that attempt to explain the observed cosmic acceleration by modifying general relativity all introduce a new scalar degree of freedom that is active on large scales, but is screened on small scales to match experiments. We demonstrate that if such screening occurs via the chameleon mechanism, such as in f(R) theory, it is possible to have order unity violation of the equivalence principle, despite the absence of explicit violation in the microscopic action. Namely, extended objects such as galaxies or constituents thereof do not all fall at the same rate. The chameleon mechanism can screen the scalar charge for large objects but not for small ones (large/small is defined by the depth of the gravitational potential and is controlled by the scalar coupling). This leads to order one fluctuations in the ratio of the inertial mass to gravitational mass. We provide derivations in both Einstein and Jordan frames. In Jordan frame, it is no longer true that all objects move on geodesics; only unscreened ones, such as test particles, do. In contrast, if the scalar screening occurs via strong coupling, such as in the Dvali-Gabadadze-Porrati braneworld model, equivalence principle violation occurs at a much reduced level. We propose several observational tests of the chameleon mechanism: 1. small galaxies should accelerate faster than large galaxies, even in environments where dynamical friction is negligible; 2. voids defined by small galaxies would appear larger compared to standard expectations; 3. stars and diffuse gas in small galaxies should have different velocities, even if they are on the same orbits; 4. lensing and dynamical mass estimates should agree for large galaxies but disagree for small ones. We discuss possible pitfalls in some of these tests. The cleanest is the third one where the mass estimate from HI rotational velocity could exceed that from stars by 30% or more. To avoid blanket screening of all objects, the most promising place to look is in voids.

Hui, Lam; Nicolis, Alberto; Stubbs, Christopher W.

2009-11-01

453

FROM CONCEPT TO EQUIVALENCY: THE 503 REGULATIONS AND THE PATHOGEN EQUIVALENCY COMMITTEE (PAPER)  

EPA Science Inventory

Since its creation in 1985, the Pathogen Equivalency Committee (PEC) has been reviewing innovative and alternative sludge disinfection technologies with regards to their abilities to protect human health and the environment. The PEC is charged to make recommendations on whether t...

454

FROM CONCEPT TO EQUIVALENCY: THE 503 REGULATIONS AND THE PATHOGEN EQUIVALENCY COMMITTEE  

EPA Science Inventory

Since its creation in 1985, the Pathogen Equivalency Committee (PEC) has been reviewing innovative and alternative sludge disinfection technologies with regards to their abilities to protect human health and the environment. The PEC is charged to make recommendations on whether t...

455

Trapping sub-micron Size Particles in Holographic Optical Tweezers  

NASA Astrophysics Data System (ADS)

Trapping of sub-micron size particles is of interest to the biological community as well as to nanoelectronic research and industry. We have employed spatially modified Gaussian beam to generate narrow optical traps within diffraction limitation. A spatial light modulator is addressed with the spatial frequencies of the required optical traps. The inverse Fourier transform is obtained at the trap plane of the optical tweezers. We have demonstrated the trapping of sub-micron particles in multiples traps, patterned numerically which is addressed to a spatial light modulator. The trap is vary stable and the particles are trapped for more than 120 seconds.

Dwivedi, G.; Gupta, A.; Shukla, M.; Kanaujia, S.; Yede, S.; Andrews, J. T.

2014-09-01

456

Radiological Protection in Space: Indication from the ICRP Task Group  

NASA Astrophysics Data System (ADS)

In 2007 the International Commission on Radiological Protection (ICRP) has established a Task Group (Radiation Protection in Space) dealing with the problems of radiation protection of astronauts in space missions. Its first task is a report on "Assessment of Radiation Exposure of Astronauts in Space". When the ICRP published its general recommendations for radiological protection in 2007 (ICRP Publication 103 following ICRP Publication 60 (1991)) it was obvious that these recommendations do not really consider the special situation of astronauts in space. The radiation field with its high content of charged particles of very high energies strongly differs from usual radiation fields on ground. For example, this has consequences for the assessment of doses in the body of astronauts. The ICRP Task Group has discussed this situation and the presentation will deal with some consequences for the concept of radiation dosimetry and radiological protection in space. This includes e. g. the assessment of organ doses and the application of the effective dose concept with its definition of radiation weighting factors. Radiation quality of high energy heavy ions may be defined different than usually performed on ground. An approach of using the quality factor concept in the definition of an "effective dose" is favored for application in space missions similar to the method proposed in NCRP Report 142. New data calculated on the basis of the reference anthropomorphic voxel phantoms recommended by ICRP support this procedure. Individual dosimetry is a further subject of discussion in the Task Group. While the operational dose equivalent quantities generally in use in radiation protection on ground are not helpful for applications in space, different procedures of the assessment of organ and effective doses are applied. The Task Group is dealing with this situation.

Dietze, Günther

457

The Shielding Function of Task Sets and Its Relaxation during Task Switching  

ERIC Educational Resources Information Center

The goal of the presented experiments was to investigate the dynamic interplay of task shielding and its relaxation during task switching. Task shielding refers to the finding that single task sets in terms of 2-choice categorization rules help shielding against distraction from irrelevant stimulus attributes. During task switching, this shielding…

Dreisbach, Gesine; Wenke, Dorit

2011-01-01

458

Investigating Perfect Timesharing: The Relationship between IM-Compatible Tasks and Dual-Task Performance  

ERIC Educational Resources Information Center

Why are dual-task costs reduced with ideomotor (IM) compatible tasks (Greenwald & Shulman, 1973; Lien, Proctor & Allen, 2002)? In the present experiments, we first examine three different measures of single-task performance (pure single-task blocks, mixed blocks, and long stimulus onset asynchrony [SOA] trials in dual-task blocks) and two measures…

Halvorson, Kimberly M.; Ebner, Herschel; Hazeltine, Eliot

2013-01-01

459

Incremental multi-robot task selection for resource constrained and interrelated tasks  

Microsoft Academic Search

When the tasks of a mission are interrelated and subject to several resource constraints, more efforts are needed to coordinate robots towards achieving the mission than independent tasks. In this work, we formulate the Coordinated Task Selection Problem (CTSP) to form the basis of an efficien t dynamic task selection scheme for allocation of interrelated tasks of a complex mission

Sanem Sariel; Tucker R. Balch; Nadia Erdogan

2007-01-01

460

Updating Sensory "versus" Task Representations during Task-Switching: Insights from Cognitive Brain Potentials in Humans  

ERIC Educational Resources Information Center

Task-cueing studies suggest that the updating of sensory and task representations both contribute to behavioral task-switch costs [Forstmann, B. U., Brass, M., & Koch, I. (2007). "Methodological and empirical issues when dissociating cue-related from task-related processes in the explicit task-cuing procedure." "Psychological Research, 71"(4),…

Perianez, Jose A.; Barcelo, Francisco

2009-01-01

461

Residual CO2 trapping in Indiana limestone.  

PubMed

We performed core flooding experiments on Indiana limestone using the porous plate method to measure the amount of trapped CO(2) at a temperature of 50 °C and two pressures: 4.2 and 9 MPa. Brine was mixed with CO(2) for equilibration, then the mixture was circulated through a sacrificial core. Porosity and permeability tests conducted before and after 884 h of continuous core flooding confirmed negligible dissolution. A trapping curve for supercritical (sc)CO(2) in Indiana showing the relationship between the initial and residual CO(2) saturations was measured and compared with that of gaseous CO(2). The results were also compared with scCO(2) trapping in Berea sandstone at the same conditions. A scCO(2) residual trapping end point of 23.7% was observed, indicating slightly less trapping of scCO(2) in Indiana carbonates than in Berea sandstone. There is less trapping for gaseous CO(2) (end point of 18.8%). The system appears to be more water-wet under scCO(2) conditions, which is different from the trend observed in Berea; we hypothesize that this is due to the greater concentration of Ca(2+) in brine at higher pressure. Our work indicates that capillary trapping could contribute to the immobilization of CO(2) in carbonate aquifers. PMID:23167314

El-Maghraby, Rehab M; Blunt, Martin J

2013-01-01

462

Fluorescent prey traps in carnivorous plants.  

PubMed

Carnivorous plants acquire most of their nutrients by capturing ants, insects and other arthropods through their leaf-evolved biological traps. So far, the best-known attractants in carnivorous prey traps are nectar, colour and olfactory cues. Here, fresh prey traps of 14 Nepenthes, five Sarracenia, five Drosera, two Pinguicula species/hybrids, Dionaea muscipula and Utricularia stellaris were scanned at UV 366 nm. Fluorescence emissions of major isolates of fresh Nepenthes khasiana pitcher peristomes were recorded at an excitation wavelength of 366 nm. N. khasiana field pitcher peristomes were masked by its slippery zone extract, and prey capture rates were compared with control pitchers. We found the existence of distinct blue fluorescence emissions at the capture spots of Nepenthes, Sarracenia and Dionaea prey traps at UV 366 nm. These alluring blue emissions gradually developed with the growth of the prey traps and diminished towards their death. On excitation at 366 nm, N. khasiana peristome 3:1 CHCl3–MeOH extract and its two major blue bands showed strong fluorescence emissions at 430–480 nm. Masking of blue emissions on peristomes drastically reduced prey capture in N. khasiana pitchers. We propose these molecular emissions as a critical factor attracting arthropods and other visitors to these carnivorous traps. Drosera, Pinguicula and Utricularia prey traps showed only red chlorophyll emissions at 366 nm. PMID:23696970

Kurup, R; Johnson, A J; Sankar, S; Hussain, A A; Sathish Kumar, C; Sabulal, B

2013-05-01

463

Oxygen Trapping in Icy Satellite Surfaces  

NASA Astrophysics Data System (ADS)

The detection of condensed O2 and/or ozone on the surfaces of some satellites orbiting within the magnetospheres of Jupiter and Saturn was attributed to the trapping of radiolytic oxygen in their icy surfaces, but previous experiments showed rapid out-diffusion of O2 from laboratory O2-H2O ice mixtures, which suggested that only very small concentrations of oxygen could be trapped in water ice. Here, we show that irradiation of ice by 100 keV ions produces radiation defects that trap large amounts of O2. The oxygen traps in a highly concentrated subsurface layer, which we investigate with secondary ion mass spectrometry. Simultaneous ion irradiation and water condensation further enhances the buildup of trapped O2 and leads to the production of ozone in the ice. Thus, in addition to other precursor species trapped in their surfaces, models describing the production of ozone and the sputtering of oxygen from icy astronomical bodies in radiation environments must account for the possibility of large amounts of trapped O2.

Teolis, B. D.; Loeffler, M. J.; Raut, U.; Shi, J.; Fama, M.; Baragiola, R. A.

2006-05-01

464

Zebrafish and mouse TASK-2 K(+) channels are inhibited by increased CO2 and intracellular acidification.  

PubMed

TASK-2 is a K2P K(+) channel considered as a candidate to mediate CO2 sensing in central chemosensory neurons in mouse. Neuroepithelial cells in zebrafish gills sense CO2 levels through an unidentified K2P K(+) channel. We have now obtained zfTASK-2 from zebrafish gill tissue that is 49 % identical to mTASK-2. Like its mouse equivalent, it is gated both by extra- and intracellular pH being activated by alkalinization and inhibited by acidification. The pHi dependence of zfTASK-2 is similar to that of mTASK-2, with pK 1/2 values of 7.9 and 8.0, respectively, but pHo dependence occurs with a pK 1/2 of 8.8 (8.0 for mTASK-2) in line with the relatively alkaline plasma pH found in fish. Increasing CO2 led to a rapid, concentration-dependent (IC50 ~1.5 % CO2) inhibition of mouse and zfTASK-2 that could be resolved into an inhibition by intracellular acidification and a CO2 effect independent of pHi change. Indeed a CO2 effect persisted despite using strongly buffered intracellular solutions abolishing any change in pHi, was present in TASK-2-K245A mutant insensitive to pHi, and also under carbonic anhydrase inhibition. The mechanism by which TASK-2 senses CO2 is unknown but requires the presence of the 245-273 stretch of amino acids in the C terminus that comprises numerous basic amino acids and is important in TASK-2 G protein subunit binding and regulation of the channel. The described CO2 effect might be of importance in the eventual roles played by TASK-2 in chemoreception in mouse and zebrafish. PMID:24081451

Peña-Münzenmayer, Gaspar; Niemeyer, María Isabel; Sepúlveda, Francisco V; Cid, L Pablo

2014-07-01

465

Task-oriented situation recognition  

NASA Astrophysics Data System (ADS)

From the advances in computer vision methods for the detection, tracking and recognition of objects in video streams, new opportunities for video surveillance arise: In the future, automated video surveillance systems will be able to detect critical situations early enough to enable an operator to take preventive actions, instead of using video material merely for forensic investigations. However, problems such as limited computational resources, privacy regulations and a constant change in potential threads have to be addressed by a practical automated video surveillance system. In this paper, we show how these problems can be addressed using a task-oriented approach. The system architecture of the task-oriented video surveillance system NEST and an algorithm for the detection of abnormal behavior as part of the system are presented and illustrated for the surveillance of guests inside a video-monitored building.

Bauer, Alexander; Fischer, Yvonne

2010-04-01

466

Stability of a trapped dipolar quantum gas  

NASA Astrophysics Data System (ADS)

We calculate the stability diagram for a trapped normal Fermi or Bose gas with dipole-dipole interactions. Our study characterizes the roles of trap geometry and temperature on the stability using Hartree-Fock theory. We find that exchange appreciably reduces stability and that, for bosons, the double instability feature in oblate trapping geometries predicted previously is still predicted by the Hartree-Fock theory. Our results are relevant to current experiments with polar molecules and will be useful in developing strategies to obtain a polar molecule Bose-Einstein condensate or degenerate Fermi gas.

Baillie, D.; Bisset, R. N.; Blakie, P. B.

2015-01-01

467

Controlling Strings of Single Trapped Atoms  

NASA Astrophysics Data System (ADS)

We control and manipulate strings of neutral atoms, trapped inside a standing wave dipole trap. We show that such a string realizes a quantum register, where coherent information is encoded in the atomic hyperfine states using microwave transitions. Furthermore, using high resolution imaging optics, we measure the absolute and relative positions of the atoms with a sub-optical wavelength resolution. The overall position of the string is then actively controlled with an optical conveyor belt. Finally, by extracting and reinserting atoms at predetermined positions with a second, perpendicular dipole trap, we aim to control the interatomic distances, prepare equidistant strings, and rearrange their order.

Rauschenbeutel, A.; Alt, W.; Dotsenko, I.; Förster, L.; Khudaverdyan, M.; Miroshnychenko, Y.; Schrader, D.; Meschede, D.

2005-12-01

468

Doughnut shape atom traps with arbitrary inclination  

NASA Astrophysics Data System (ADS)

Since the invention of magneto-optical trap (MOT), there have been several experimental and theoretical studies of the density distribution in these devices. To the best of our knowledge, only horizontal orbital traps have been observed, perpendicular to the coil axis. In this work we report the observation of distributions of trapped atoms in pure circular orbits without a nucleus whose orbital plane is tilted up to 90 degrees with respect to the horizontal plane. We have used a stabilized time phase optical array in our experiments and conventional equipment used for MOT.

Masegosa, R. R. Y.; Moya-Cessa, H.; Chavez-Cerda, S.

2006-02-01

469

Microparticle trapping in an ultrasonic Bessel beam  

PubMed Central

This paper describes an acoustic trap consisting of a multi-foci Fresnel lens on 127??m thick lead zirconate titanate sheet. The multi-foci Fresnel lens was designed to have similar working mechanism to an Axicon lens and generates an acoustic Bessel beam, and has negative axial radiation force capable of trapping one or more microparticle(s). The fabricated acoustic tweezers trapped lipid particles ranging in diameter from 50 to 200??m and microspheres ranging in diameter from 70 to 90??m at a distance of 2 to 5?mm from the tweezers without any contact between the transducer and microparticles. PMID:22247566

Choe, Youngki; Kim, Jonathan W.; Shung, K. Kirk; Kim, Eun Sok

2011-01-01

470

How to Set a Pitfall Trap  

NSDL National Science Digital Library

In this Biodiversity Counts activity, students learn how to create and set up a pitfall trap to catch soil dwellers. The online activity page includes easy-to-follow directions for building a trap with recycled plastic containers, stones, wood/cardboard, and a bait of the students' choosing. Students let the trap sit either for a few hours or overnight to see what they have caught. To expand their investigation, students are challenged to experiment with different baits to see if they can attract different arthropods.

471

The Canadian Penning Trap mass spectrometer  

NASA Astrophysics Data System (ADS)

The Canadian Penning Trap (CPT) mass spectrometer located at the ATLAS facility of Argonne National Laboratory is an online Penning trap system used for mass measurements of high accuracy on short-lived isotopes. It uses a gas catcher as a novel way to transform radioactive ions efficiently from different sources into cooled beams which are injected into ion traps for further preparation and measurement. The CPT has recently been successfully used to make precise mass measurements on over 40 neutron-rich and neutron-deficient radioactive nuclides related to astrophysical processes.

Wang, J. C.; Savard, G.; Sharma, K. S.; Clark, J. A.; Zhou, Z.; Levand, A. F.; Boudreau, C.; Buchinger, F.; Crawford, J. E.; Greene, J. P.; Gulick, S.; Lee, J. K. P.; Sprouse, G. D.; Trimble, W.; Vaz, J.; Zabransky, B. Z.

2004-12-01

472

Energy Conservation Through Effective Steam Trapping  

E-print Network

, historically, is one of the earliest designs in steam traps. The actuating element is a hollow stainless steel float connected via a linkage to the di.scharge orifice The ball floats on condensate entering the trap body and opens the valve. As condensation... at precisely the rate of condensation. It is an automatic throttling valve. The discharge orifice is generally located near the bottom of this trap so that even when fully closed water seal is maintained above it. This prevents the loss of live steam from...

Diamante, L.; Nagengast, C.

1979-01-01

473

Effect of Trapping on Vortices in Plasma  

NASA Astrophysics Data System (ADS)

Microscopic trapping of electrons is considered in one- and two-dimensional potential wells (shallow and deep) and its effect on vortex formation is investigated by deriving modified Hasegawa Mima (HM) equations. Inhomogenieties in the number density and magnetic field are taken into account. The modified HM equations are analysed by considering bounce frequencies of the trapped particles. Solitary vortices are obtained via Kortweg deVries (KdV) type of equations and both exact and Sagdeev potential solutions are obtained. In general it is observed that trapping produces stronger non-linearities and this leads to the modification of the original HM equation.

Siddiqui, H.; Shah, H. A.; Tsintsadze, N. L.

2008-09-01

474

Bereavement tasks for nursing students.  

PubMed

Preparing students to face the loss of patients through suffering and death is not an easy task. The author describes two separate and unique teaching/learning strategies that provided nursing students with practical applications to cope with their bereavement experiences during an oncology clinical rotation. The article's emphasis is on the critical need of adequate and contemporary clinical integration of death and bereavement concepts and nursing education. PMID:8788822

Clingerman, E M

1996-01-01

475

Exact mapping of the 2+1 Dirac oscillator onto the Jaynes-Cummings model: Ion-trap experimental proposal  

NASA Astrophysics Data System (ADS)

We study the dynamics of the 2+1 Dirac oscillator exactly and find spin oscillations due to a Zitterbewegung of purely relativistic origin. We find an exact mapping of this quantum-relativistic system onto a Jaynes-Cummings model, describing the interaction of a two-level atom with a quantized single-mode field. This equivalence allows us to map a series of quantum optical phenomena onto the relativistic oscillator and vice versa. We make a realistic experimental proposal, in reach with current technology, for studying the equivalence of both models using a single trapped ion.

Bermudez, A.; Martin-Delgado, M. A.; Solano, E.

2007-10-01

476

Inhomogeneous electric field effects in a linear RF quadruple trap  

NASA Technical Reports Server (NTRS)

The exact potential corresponding to confining fields inside a linear rf quadrupole particle trap of finite length is presented. The analytic expressions for the trapping potential is derived by introducing a linear trap employing a relatively simple cylindrical geometry and solving Laplace's equation for the trap electrodes. The finite length of linear traps results in field distortion near the trap ends. An exact analytic determination of the fields is useful because the profile of the trapped ion cloud is highly dependent on the fields confining it. It is shown that near the ends of the trap, the effective potential arising from the rf fields acts to propel particles out of the trap, and further, that the addition of a dc bias generates an inhomogeneous in the trap that influences the particles both perpendicularly to and along the trap's long axis.

Melborne, R. K.

1990-01-01

477

Tests of the weak equivalence principle  

NASA Astrophysics Data System (ADS)

The Einstein equivalence principle is the foundation for general relativity and all metric theories of gravity. Of its three tenets—the equality of acceleration of test bodies, or weak equivalence principle; the validity of Lorentz invariance in local freely falling frames; and the position invariance of local physical laws—the weak equivalence principle has played the most important role historically, and continues to be a focus of intense theoretical and experimental investigation. From the probably apocryphal 16th century demonstrations by Galileo at Pisa's leaning tower to the sensitive torsion-balance measurements of today (both pictured on the cover of this issue), this principle, dubbed WEP, has been crucial to the development of gravitation theory. The universality of the rate of acceleration of all types of matter in a gravitational field can be taken as evidence that gravitation is fundamentally determined by the geometry, or metric, of spacetime. Newton began his magnum opus 'The Principia' with a discussion of WEP and his experiments to verify it, while Einstein took WEP for granted in his construction of general relativity, never once referring to the epochal experiments by Baron Eötvös. The classic 1964 experiment of Roll, Krotkov and Dicke ushered in the modern era of high-precision tests, and the search for a 'fifth force' during the late 1980s (instigated, ironically, by purported anomalies in Eötvös's old data) caused the enterprise to pivot from pure tests of the foundation of GR to searches for new physics beyond the standard model of the non-gravitational interactions. Today, the next generation of experimental tests of WEP are being prepared for launch or are being developed, with the goal of reaching unprecedented levels of sensitivity, in search of signatures of interactions inspired by string theory, extra dimensions and other concepts from the world of high-energy physics. At the same time observations continue using lunar laser ranging and binary pulsar timing to test a stronger version of WEP, in order to verify whether gravitational mass/energy itself falls with the same acceleration as normal matter. This focus issue brings together a set of invited papers to explore the many aspects of testing WEP. An introductory article laying out the theoretical context is followed by articles on current laboratory experiments. Four articles describe the latest results from lunar laser ranging and binary pulsar timing, while two articles discuss progress toward testing the free fall of antihydrogen. The final four articles address future experiments to be carried out in space on orbiting or sub-orbital platforms. We hope that readers will take away from these articles both the centrality of this principle to gravitational physics and the rich and wide-ranging experimental activity that is being carried out to test it. C C Speake and C M WillGuest Editors

Speake, C. C.; Will, C. M.

2012-09-01

478

Quality of reporting of clinical non-inferiority and equivalence randomised trials - update and extension  

PubMed Central

Background Non-inferiority and equivalence trials require tailored methodology and therefore adequate conduct and reporting is an ambitious task. The aim of our review was to assess whether the criteria recommended by the CONSORT extension were followed. Methods We searched the Medline database and the Cochrane Central Register for reports of randomised non-inferiority and equivalence trials published in English language. We excluded reports on bioequivalence studies, reports targeting on other than the main results of a trial, and articles of which the full-text version was not available. In total, we identified 209 reports (167 non-inferiority, 42 equivalence trials) and assessed the reporting and methodological quality using abstracted items of the CONSORT extension. Results Half of the articles did not report on the method of randomisation and only a third of the trials were reported to use blinding. The non-inferiority or equivalence margin was defined in most reports (94%), but was justified only for a quarter of the trials. Sample size calculation was reported for a proportion of 90%, but the margin was taken into account in only 78% of the trials reported. Both intention-to-treat and per-protocol analysis were presented in less than half of the reports. When reporting the results, a confidence interval was given for 85% trials. A proportion of 21% of the reports presented a conclusion that was wrong or incomprehensible. Overall, we found a substantial lack of quality in reporting and conduct. The need to improve also applied to aspects generally recommended for randomised trials. The quality was partly better in high-impact journals as compared to others. Conclusions There are still important deficiencies in the reporting on the methodological approach as well as on results and interpretation even in high-impact journals. It seems to take more than guidelines to improve conduct and reporting of non-inferiority and equivalence trials. PMID:23157733

2012-01-01

479

Collisionless Trapped Electron Mode Turbulence  

NASA Astrophysics Data System (ADS)

Collisionless Trapped Electron Mode (CTEM) turbulence is a likely canidate for explaining anomolous transport in tokamak discharges that have a strong density gradient relative to the ion temperature gradient. Here, CTEM turbulence is investigated using the Gyrokinetic ?f GEM code. GEM is electromagnetic, includes full drift-kinetic electrons, generaly axisymmetric equilbria, collisions and minority species. Here, the flux-tube limit is taken and ? is so small that the simulations are essentially electrostatic. Linear theory predicts that the instability occurs at ?2?RLn>1, which agrees very well with the simulation results. With increasing density gradient, it is observed that the most unstable mode transitions from a CTEM to drift wave mode and the short-wavelength modes are most unstable ( 2 > k?i> 1). Nonlinear simulations are underway to address the parametric dependence of particle and energy transport. The importance of zonal flows for CTEM turbulence, is still not well understood and is under investigation. D. R. Ernst et. al., Phys. Plasma 11 (2004) 2637 T. Dannert and F. Jenko, Phys. Plasma 12 (2005) 072309 R. Gatto et. al., Phys. Plasma 13 (2006) 022306 Y. Chen and S. E. Parker, J. Comput. Phys. 189 (2003) 463 Y. Chen ad S.E. Parker, accepted, to appear in J. Comput. Phys. (2006) J. Wesson (1997) Tokamaks, Oxford Science

Lang, Jianying; Chen, Yang; Parker, Scott

2006-10-01

480

Nonlinear spectroscopy of trapped ions  

NASA Astrophysics Data System (ADS)

Nonlinear spectroscopy employs a series of laser pulses to interrogate dynamics in large interacting many-body systems, and it has become a highly successful method for experiments in chemical physics. Current quantum optical experiments approach system sizes and levels of complexity that require the development of efficient techniques to assess spectral and dynamical features with scalable experimental overhead. However, established methods from optical spectroscopy of macroscopic ensembles cannot be applied straightforwardly to few-atom systems. Based on the ideas proposed in M. Gessner et al., (arXiv:1312.3365), we develop a diagrammatic approach to construct nonlinear measurement protocols for controlled quantum systems, and we discuss experimental implementations with trapped ion technology in detail. These methods, in combination with distinct features of ultracold-matter systems, allow us to monitor and analyze excitation dynamics in both the electronic and vibrational degrees of freedom. They are independent of system size, and they can therefore reliably probe systems in which, e.g., quantum state tomography becomes prohibitively expensive. We propose signals that can probe steady-state currents, detect the influence of anharmonicities on phonon transport, and identify signatures of chaotic dynamics near a quantum phase transition in an Ising-type spin chain.

Schlawin, Frank; Gessner, Manuel; Mukamel, Shaul; Buchleitner, Andreas

2014-08-01

481

A modular telerobotic task execution system  

NASA Technical Reports Server (NTRS)

A telerobot task execution system is proposed to provide a general parametrizable task execution capability. The system includes communication with the calling system, e.g., a task planning system, and single- and dual-arm sensor-based task execution with monitoring and reflexing. A specific task is described by specifying the parameters to various available task execution modules including trajectory generation, compliance control, teleoperation, monitoring, and sensor fusion. Reflex action is achieved by finding the corresponding reflex action in a reflex table when an execution event has been detected with a monitor.

Backes, Paul G.; Tso, Kam S.; Hayati, Samad; Lee, Thomas S.

1990-01-01

482

Continuous three-dimensional radiation dosimetry in tissue-equivalent phantoms using electron paramagnetic resonance in L-. cap alpha. -alanine  

SciTech Connect

A new tissue-equivalent phantom material has been developed which also acts as a dosimeter. The new phantom material has a similar elemental composition to that of soft tissue and has a density 1.1 g/cm/sup 3/. The phantom has an agar-gel base, and contains crystallized L-..cap alpha..-alanine which traps radiation-induced free radicals. Samples from the phantom were analyzed by an electron paramagnetic resonance (EPR) spectrometer and the intensity of the EPR signal was related to the absorbed dose. When calibrated, the phantom material acts as a dosimeter, with applications in radiation therapy.

Wielopolski, L.; Maryanski, M.; Ciesielski, B.; Forman, A.; Reinstein, L.E.; Meek, A.G.

1987-07-01

483

Double nanohole optical trapping: dynamics and protein-antibody co-trapping.  

PubMed

A double nanohole in a metal film can optically trap nanoparticles such as polystyrene/silica spheres, encapsulated quantum dots and up-converting nanoparticles. Here we study the dynamics of trapped particles, showing a skewed distribution and low roll-off frequency that are indicative of Kramers-hopping at the nanoscale. Numerical simulations of trapped particles show a double-well potential normally found in Kramers-hopping systems, as well as providing quantitative agreement with the overall trapping potential. In addition, we demonstrate co-trapping of bovine serum albumin (BSA) with anti-BSA by sequential delivery in a microfluidic channel. This co-trapping opens up exciting possibilities for the study of protein interactions at the single particle level. PMID:23429640

Zehtabi-Oskuie, Ana; Jiang, Hao; Cyr, Bryce R; Rennehan, Douglas W; Al-Balushi, Ahmed A; Gordon, Reuven

2013-07-01

484

Control of diesel soot and NOx emissions with a particulate trap and EGR.  

PubMed

The exhaust gas recirculation (EGR), coupled with a high-collection efficiency particulate trap to simultaneously control smoke and NOx emissions from diesel engines were studied. This ceramic trap developed previously provided the soot cleaning efficiency of 99%, the regeneration efficiency reaches 80% and the ratio of success reaches 97%, which make EGR used in diesel possible. At the presence of EGR, opening of the regeneration control valve of the trap was over again optimized to compensate for the decrease of the oxygen concentration in the exhaust gas resulted from EGR. The results indicated the cleaning efficiency and regeneration performance of the trap were maintained at the same level except that the back pressure increased faster. A new EGR system was developed, which is based on a wide range oxygen (UEGO) sensor. Experiments were carried out under steady state conditions while maintaining the engine speed at 1600 r/min, setting the engine loads at 0%, 25%, 50%, 75% and 100% respectively. Throughout each test the EGR rate was kept at nine different settings and data were taken with the gas analyzer and UEGO sensor. Then, the EGR rate and engine load maps, which showed the tendencies of NOx, CO and HC emissions from diesel engine, were made using the measured data. Using the maps, the author set up the EGR regulation, the relationship between the optimal amounts of EGR flow and the equivalence ratio, sigma, where sigma = 14.5/AFR. PMID:16295898

Liu, Rui-xiang; Gao, Xi-yan; Yang, De-sheng; Xu, Xiao-guang

2005-01-01

485

Prediction of Collective Characteristics for Ion Ensembles in Quadrupole Ion Traps Without Trajectory Simulations  

SciTech Connect

Fundamental aspects are presented of a two-temperature moment theory for quadrupole ion traps developed via transformation of the Boltzmann equation. Because the Boltzmann equation reflects changes to an ion distribution as a whole, the resulting general moment equation describes changes in the ensemble average for any function of ion velocity. Thus, the system of differential equations, formed from the general moment equation, can be solved directly (normally, by numerical methods) for average values of the velocity and of the effective temperature (or equivalently, center-of-mass energy), each as a function of time and position. The equations contain parameterized variables ! a and ! q , which are similar to those commonly used in ion trap studies, and ! b and ! d , which are parameterized forms of the voltages applied to the endcaps, to account for both ideal and commonly used ion trap configurations. Examples illustrate some of the capabilities of moment theory for predicting the time- and position-dependent characteristics of ion ensembles during various processes in ion traps of selected configurations.

Goeringer, Doug [ORNL; Viehland, Mr. Larry A. [Chatham College, Pittsburgh; Danailov, Daniel M. [Chatham College, Pittsburgh

2006-01-01

486

VERSE - Virtual Equivalent Real-time Simulation  

NASA Technical Reports Server (NTRS)

Distributed real-time simulations provide important timing validation and hardware in the- loop results for the spacecraft flight software development cycle. Occasionally, the need for higher fidelity modeling and more comprehensive debugging capabilities - combined with a limited amount of computational resources - calls for a non real-time simulation environment that mimics the real-time environment. By creating a non real-time environment that accommodates simulations and flight software designed for a multi-CPU real-time system, we can save development time, cut mission costs, and reduce the likelihood of errors. This paper presents such a solution: Virtual Equivalent Real-time Simulation Environment (VERSE). VERSE turns the real-time operating system RTAI (Real-time Application Interface) into an event driven simulator that runs in virtual real time. Designed to keep the original RTAI architecture as intact as possible, and therefore inheriting RTAI's many capabilities, VERSE was implemented with remarkably little change to the RTAI source code. This small footprint together with use of the same API allows users to easily run the same application in both real-time and virtual time environments. VERSE has been used to build a workstation testbed for NASA's Space Interferometry Mission (SIM PlanetQuest) instrument flight software. With its flexible simulation controls and inexpensive setup and replication costs, VERSE will become an invaluable tool in future mission development.

Zheng, Yang; Martin, Bryan J.; Villaume, Nathaniel

2005-01-01

487

The Equivalence of Time and Gravitational Field  

NASA Astrophysics Data System (ADS)

The relationship between energy, time and space is still not solved in an appropriate manner. According to Newton's concept of time and space, both have to be taken as absolute. If we follow Leibniz and his arguments, space and time are relative. Since Einstein's theory of relativity we know at least that energy, time and space are deeply related. Albert Einstein originally predicted that time is nothing absolute but something relative, time changes and can change. Especially, time and gravitational field are related somehow even in detail if we still don't know how. According to the gravitational time dilation, the lower the gravitational potential, the more slowly time passes and vice versa. Somehow, it appears to be that the behaviour of time is directly linked to the behaviour of the gravitational field. The aim of this publication is to work out the interior logic between time and gravitational field and to make the proof that time is equivalent to the gravitational field and vice versa.

Baruk?i?a, Ilija

488

A restricted proof that the weak equivalence principle implies the Einstein equivalence principle  

NASA Technical Reports Server (NTRS)

Schiff has conjectured that the weak equivalence principle (WEP) implies the Einstein equivalence principle (EEP). A proof is presented of Schiff's conjecture, restricted to: (1) test bodies made of electromagnetically interacting point particles, that fall from rest in a static, spherically symmetric gravitational field; (2) theories of gravity within a certain broad class - a class that includes almost all complete relativistic theories that have been found in the literature, but with each theory truncated to contain only point particles plus electromagnetic and gravitational fields. The proof shows that every nonmentric theory in the class (every theory that violates EEP) must violate WEP. A formula is derived for the magnitude of the violation. It is shown that WEP is a powerful theoretical and experimental tool for constraining the manner in which gravity couples to electromagnetism in gravitation theories.

Lightman, A. P.; Lee, D. L.

1973-01-01

489

Evaluation of methyl eugenol and cue-lure traps with solid lure and insecticide dispensers for fruit fly monitoring and male annihilation in the Hawaii Areawide Pest Management Program.  

PubMed

Methyl eugenol (ME) and cue-lure (C-L) traps with solid lure dispensers were deployed in areas with low and high populations of oriental fruit fly, Bactrocera dorsalis (Hendel), and melon fly, Bactrocera cucurbitae (Coquillett), respectively. In low-density areas, standard Jackson traps or Hawaii Fruit Fly Areawide Pest Management (AWPM) traps with FT Mallet ME wafers impregnated with dimethyl dichloro-vinyl phosphate (DDVP) or AWPM traps with Scentry ME cones and vapor tape performed equally as well as standard Jackson traps with liquid ME/C-L and naled. Standard Jackson traps or AWPM traps with FT Mallet C-L wafers impregnated with DDVP or AWPM traps with Scentry C-L plugs with vapor tape performed equally as well as standard Jackson traps with a lure-naled solution. In high density areas, captures with traps containing FT Mallet wafers (ME and C-L) outperformed AWPM traps with Scentry cones and plugs (ME and C-L) with DDVP insecticidal strips over a 6-mo period. Captures of B. dorsalis and B. cucurbitae with wafers containing both ME and raspberry ketone (FT Mallet MC) were equivalent to those containing separate lures. From a worker safety and convenience standpoint, FT Mallet ME and C-L wafers with DDVP or Scentry plugs, with or without DDVP vapor tape, are more convenient and safer to handle than standard liquid insecticide formulations used for monitoring and male annihilation programs in Hawaii, and for detections traps used on the U.S. mainland. Furthermore, the FT Mallet MC wafer might be used in a single trap in place of two separate traps for detection of both ME and C-L responding fruit flies. PMID:20429456

Vargas, Roger I; Mau, Ronald F L; Stark, John D; Piñero, Jaime C; Leblanc, Luc; Souder, Steven K

2010-04-01

490

Scaling the ion trap quantum processor.  

PubMed

Trapped atomic ions are standards for quantum information processing, serving as quantum memories, hosts of quantum gates in quantum computers and simulators, and nodes of quantum communication networks. Quantum bits based on trapped ions enjoy a rare combination of attributes: They have exquisite coherence properties, they can be prepared and measured with nearly 100% efficiency, and they are readily entangled with each other through the Coulomb interaction or remote photonic interconnects. The outstanding challenge is the scaling of trapped ions to hundreds or thousands of qubits and beyond, at which scale quantum processors can outperform their classical counterparts in certain applications. We review the latest progress and prospects in that effort, with the promise of advanced architectures and new technologies, such as microfabricated ion traps and integrated photonics. PMID:23471398

Monroe, C; Kim, J

2013-03-01

491

Rainbow Trapping in Hyperbolic Metamaterial Waveguide  

PubMed Central

The recent reported trapped “rainbow” storage of light using metamaterials and plasmonic graded surface gratings has generated considerable interest for on-chip slow light. The potential for controlling the velocity of broadband light in guided photonic structures opens up tremendous opportunities to manipulate light for optical modulation, switching, communication and light-matter interactions. However, previously reported designs for rainbow trapping are generally constrained by inherent difficulties resulting in the limited experimental realization of this intriguing effect. Here we propose a hyperbolic metamaterial structure to realize a highly efficient rainbow trapping effect, which, importantly, is not limited by those severe theoretical constraints required in previously reported insulator-negative-index-insulator, insulator-metal-insulator and metal-insulator-metal waveguide tapers, and therefore representing a significant promise to realize the rainbow trapping structure practically. PMID:23409240

Hu, Haifeng; Ji, Dengxin; Zeng, Xie; Liu, Kai; Gan, Qiaoqiang

2013-01-01

492

Are Your Steam Traps Leaking Money?  

ERIC Educational Resources Information Center

Contends that small defects in steam heating systems often go unnoticed, while efficiency drops. Presents guidelines for detecting steam loss through trap orifices and determining how much they are costing. (Author/MLF)

American School and University, 1974

1974-01-01

493

Trapped Electron Precession Shear Induced Fluctuation Decorrelation  

SciTech Connect

We consider the effects of trapped electron precession shear on the microturbulence. In a similar way the strong E x B shear reduces the radial correlation length of ambient fluctuations, the radial variation of the trapped electron precession frequency can reduce the radial correlation length of fluctuations associated with trapped electrons. In reversed shear plasmas, with the explicit dependence of the trapped electron precession shearing rate on B(subscript)theta, the sharp radial gradient of T(subscript)e due to local electron heating inside qmin can make the precession shearing mechanism more effective, and reduce the electron thermal transport constructing a positive feedback loop for the T(subscript)e barrier formation.

T.S. Hahm; P.H. Diamond; E.-J. Kim

2002-07-29

494

Molten Hydroxide Trapping Process for Radioiodine  

SciTech Connect

A molten hydroxide trapping process has been considered for removing radioiodine species from off-gas streams whereby iodine is reacted directly with molten hydroxides such as NaOH or KOH. The resulting product is the corresponding iodide, which can be separated by simple cooling of the molten mixture to grow the iodide primary phase once the mixture reaches 70-80 mol% in the iodide component. Thermodynamic analysis indicates that such a chemical process is highly favorable. Experimental testing of the trapping process using molecular iodine showed trapping of up to 96% of the volatile iodine. The trapping efficiency was dependent on operational parameters such as temperature and gas-melt contact efficiency, and higher efficiencies are expected as the process is further developed. While an iodide phase could be effectively isolated by slow cooling of a molten iodide-hydroxide mixture, the persistent appearance of hydroxide indicated that an appreciable solubility of hydroxide occurred in the iodide phase.

Trowbridge, L.D.

2003-01-28

495

Trapped Ion Optical Clocks at NPL  

NASA Astrophysics Data System (ADS)

Forbidden transitions in single laser-cooled trapped ions provide highly stable and accurate references for optical frequency standards. This paper describes recent progress on strontium and ytterbium ion optical frequency standards under development at NPL.

Margolis, H. S.; Barwood, G. P.; Hosaka, K.; Huang, G.; Klein, H. A.; Lea, S. N.; Stannard, A.; Walton, B. R.; Webster, S. A.; Gill, P.

2006-11-01

496

The BOLD Response during Stroop Task-Like Inhibition Paradigms: Effects of Task Difficulty and Task-Relevant Modality  

ERIC Educational Resources Information Center

Previous studies of the Stroop task propose two key mediators: the prefrontal and cingulate cortices but hints exist of functional specialization within these regions. This study aimed to examine the effect of task modality upon the prefrontal and cingulate response by examining the response to colour, number, and shape Stroop tasks whilst BOLD…

Mitchell, Rachel L. C.

2005-01-01

497

On biodiversity conservation and poverty traps  

PubMed Central

This paper introduces a special feature on biodiversity conservation and poverty traps. We define and explain the core concepts and then identify four distinct classes of mechanisms that define important interlinkages between biodiversity and poverty. The multiplicity of candidate mechanisms underscores a major challenge in designing policy appropriate across settings. This framework is then used to introduce the ensuing set of papers, which empirically explore these various mechanisms linking poverty traps and biodiversity conservation. PMID:21873176

Barrett, Christopher B.; Travis, Alexander J.; Dasgupta, Partha

2011-01-01

498

Cryptography, Quantum Computation and Trapped Ions  

Microsoft Academic Search

The significance of quantum computation for cryptography is discussed.\\u000aFollowing a brief survey of the requirements for quantum computational\\u000ahardware, an overview of the ion trap quantum computation project at Los Alamos\\u000ais presented. The physical limitations to quantum computation with trapped ions\\u000aare analyzed and an assessment of the computational potential of the technology\\u000ais made.

Richard J. Hughes

1997-01-01

499

Deadly Glue — Adhesive Traps of Carnivorous Plants  

Microsoft Academic Search

\\u000a Carnivorous plants trap and utilize animals in order to improve their supply with mineral nutrients. One strategy for prey\\u000a capture is the use of adhesive traps, i.e., leaves that produce sticky substances. Sticky shoots are widespread in the plant\\u000a kingdom and serve to protect the plant, especially flowers and seeds. In some taxa, mechanisms have been developed to absorb\\u000a nutrients

Wolfram Adlassnig; Thomas Lendl; Marianne Peroutka; Ingeborg Lang

500

Actin filament mechanics in the laser trap  

Microsoft Academic Search

Numerous biological processes, including muscular contraction, depend upon the mechanical properties of actin filaments. One\\u000a such property is resistance to bending (flexural rigidity, EI). To estimate EI, we attached the ends of fluorescently labelled\\u000a actin filaments to two microsphere‘handles’ captured in independent laser traps. The positions of the traps were manipulated\\u000a to apply a range of tensions (0--8 pN)to the

D. E. DUPUIS; W. H. GUILFORD; J. WU; D. M. WARSHAW

1997-01-01