Segalowitz, Norman S; Doucerain, Marina M; Meuter, Renata F I; Zhao, Yue; Hocking, Julia; Ryder, Andrew G
2016-01-01
This research explored the feasibility of using multidimensional scaling (MDS) analysis in novel combination with other techniques to study comprehension of epistemic adverbs expressing doubt and certainty (e.g., evidently, obviously, probably) as they relate to health communication in clinical settings. In Study 1, Australian English speakers performed a dissimilarity-rating task with sentence pairs containing the target stimuli, presented as "doctors' opinions." Ratings were analyzed using a combination of cultural consensus analysis (factor analysis across participants), weighted-data classical-MDS, and cluster analysis. Analyses revealed strong within-community consistency for a 3-dimensional semantic space solution that took into account individual differences, strong statistical acceptability of the MDS results in terms of stress and explained variance, and semantic configurations that were interpretable in terms of linguistic analyses of the target adverbs. The results confirmed the feasibility of using MDS in this context. Study 2 replicated the results with Canadian English speakers on the same task. Semantic analyses and stress decomposition analysis were performed on the Australian and Canadian data sets, revealing similarities and differences between the two groups. Overall, the results support using MDS to study comprehension of words critical for health communication, including in future studies, for example, second language speaking patients and/or practitioners. More broadly, the results indicate that the techniques described should be promising for comprehension studies in many communicative domains, in both clinical settings and beyond, and including those targeting other aspects of language and focusing on comparisons across different speech communities.
Segalowitz, Norman S.; Doucerain, Marina M.; Meuter, Renata F. I.; Zhao, Yue; Hocking, Julia; Ryder, Andrew G.
2016-01-01
This research explored the feasibility of using multidimensional scaling (MDS) analysis in novel combination with other techniques to study comprehension of epistemic adverbs expressing doubt and certainty (e.g., evidently, obviously, probably) as they relate to health communication in clinical settings. In Study 1, Australian English speakers performed a dissimilarity-rating task with sentence pairs containing the target stimuli, presented as “doctors' opinions.” Ratings were analyzed using a combination of cultural consensus analysis (factor analysis across participants), weighted-data classical-MDS, and cluster analysis. Analyses revealed strong within-community consistency for a 3-dimensional semantic space solution that took into account individual differences, strong statistical acceptability of the MDS results in terms of stress and explained variance, and semantic configurations that were interpretable in terms of linguistic analyses of the target adverbs. The results confirmed the feasibility of using MDS in this context. Study 2 replicated the results with Canadian English speakers on the same task. Semantic analyses and stress decomposition analysis were performed on the Australian and Canadian data sets, revealing similarities and differences between the two groups. Overall, the results support using MDS to study comprehension of words critical for health communication, including in future studies, for example, second language speaking patients and/or practitioners. More broadly, the results indicate that the techniques described should be promising for comprehension studies in many communicative domains, in both clinical settings and beyond, and including those targeting other aspects of language and focusing on comparisons across different speech communities. PMID:27199798
Slowly but Surely: Adverbs Support Verb Learning in 2-Year-Olds.
Syrett, Kristen; Arunachalam, Sudha; Waxman, Sandra R
2014-07-01
To acquire the meanings of verbs, toddlers make use of the surrounding linguistic information. For example, two-year-olds successfully acquire novel transitive verbs that appear in semantically rich frames containing content nouns ("The boy is gonna pilk a balloon"). But, they have difficulty with pronominal frames ("He is gonna pilk it") (Arunachalam & Waxman, 2010). We hypothesized that adverbs might facilitate toddlers' verb learning in these sparse pronominal frames, if their semantic content directed toddlers' attention to aspects of the event that are relevant to the verb's meaning (e.g., the manner of motion). As predicted, the semantic information from a specific manner-of-motion adverb (slowly) supported verb learning, but other adverbs lacking this semantic content (nicely, right now) did not. These results provide the first evidence that adverbs can facilitate verb learning in toddlers, and highlight the interaction of syntactic and semantic information in word learning.
Sentence Adverbs in the Kingdom of Agree
ERIC Educational Resources Information Center
Shu, Chih-hsiang
2011-01-01
This dissertation offers a novel account of the syntax of sentence adverbs. The need for a new account is clear from the lack of descriptive coverage and theoretical coherence in current work on adverbial syntax. Descriptively, the majority of work has so far neglected the fact that sentence adverbs behave syntactically like typical focusing…
Charged-particle motion in multidimensional magnetic-field turbulence
NASA Technical Reports Server (NTRS)
Giacalone, J.; Jokipii, J. R.
1994-01-01
We present a new analysis of the fundamental physics of charged-particle motion in a turbulent magnetic field using a numerical simulation. The magnetic field fluctuations are taken to be static and to have a power spectrum which is Kolmogorov. The charged particles are treated as test particles. It is shown that when the field turbulence is independent of one coordinate (i.e., k lies in a plane), the motion of these particles across the magnetic field is essentially zero, as required by theory. Consequently, the only motion across the average magnetic field direction that is allowed is that due to field-line random walk. On the other hand, when a fully three-dimensional realization of the turbulence is considered, the particles readily cross the field. Transport coefficients both along and across the ambient magnetic field are computed. This scheme provides a direct computation of the Fokker-Planck coefficients based on the motions of individual particles, and allows for comparison with analytic theory.
Robust, multidimensional mesh motion based on Monge-Kantorovich equidistribution
Delzanno, G L; Finn, J M
2009-01-01
Mesh-motion (r-refinement) grid adaptivity schemes are attractive due to their potential to minimize the numerical error for a prescribed number of degrees of freedom. However, a key roadblock to a widespread deployment of the technique has been the formulation of robust, reliable mesh motion governing principles, which (1) guarantee a solution in multiple dimensions (2D and 3D), (2) avoid grid tangling (or folding of the mesh, whereby edges of a grid cell cross somewhere in the domain), and (3) can be solved effectively and efficiently. In this study, we formulate such a mesh-motion governing principle, based on volume equidistribution via Monge-Kantorovich optimization (MK). In earlier publications [1, 2], the advantages of this approach in regards to these points have been demonstrated for the time-independent case. In this study, demonstrate that Monge-Kantorovich equidistribution can in fact be used effectively in a time stepping context, and delivers an elegant solution to the otherwise pervasive problem of grid tangling in mesh motion approaches, without resorting to ad-hoc time-dependent terms (as in moving-mesh PDEs, or MMPDEs [3, 4]). We explore two distinct r-refinement implementations of MK: direct, where the current mesh relates to an initial, unchanging mesh, and sequential, where the current mesh is related to the previous one in time. We demonstrate that the direct approach is superior in regards to mesh distortion and robustness. The properties of the approach are illustrated with a paradigmatic hyperbolic PDE, the advection of a passive scalar. Imposed velocity flow fields or varying vorticity levels and flow shears are considered.
The Syntactic Positions of Adverbs and the Second Language Acquisition
ERIC Educational Resources Information Center
Zhang, Zi-hong
2010-01-01
Based on the theory of linguistic universal and Second Language Acquisition (SLA), the paper discusses the acquisition of syntactic positions of adverbs in English. According to the data collected, the paper concludes that what adult learners acquire about adverbs is the distinction of different adverbs and the different scopes they take.…
Viola, Francesco; Coe, Ryan L; Owen, Kevin; Guenther, Drake A; Walker, William F
2008-12-01
Image registration and motion estimation play central roles in many fields, including RADAR, SONAR, light microscopy, and medical imaging. Because of its central significance, estimator accuracy, precision, and computational cost are of critical importance. We have previously presented a highly accurate, spline-based time delay estimator that directly determines sub-sample time delay estimates from sampled data. The algorithm uses cubic splines to produce a continuous representation of a reference signal and then computes an analytical matching function between this reference and a delayed signal. The location of the minima of this function yields estimates of the time delay. In this paper we describe the MUlti-dimensional Spline-based Estimator (MUSE) that allows accurate and precise estimation of multi-dimensional displacements/strain components from multi-dimensional data sets. We describe the mathematical formulation for two- and three-dimensional motion/strain estimation and present simulation results to assess the intrinsic bias and standard deviation of this algorithm and compare it to currently available multi-dimensional estimators. In 1000 noise-free simulations of ultrasound data we found that 2D MUSE exhibits maximum bias of 2.6 x 10(-4) samples in range and 2.2 x 10(-3) samples in azimuth (corresponding to 4.8 and 297 nm, respectively). The maximum simulated standard deviation of estimates in both dimensions was comparable at roughly 2.8 x 10(-3) samples (corresponding to 54 nm axially and 378 nm laterally). These results are between two and three orders of magnitude better than currently used 2D tracking methods. Simulation of performance in 3D yielded similar results to those observed in 2D. We also present experimental results obtained using 2D MUSE on data acquired by an Ultrasonix Sonix RP imaging system with an L14-5/38 linear array transducer operating at 6.6 MHz. While our validation of the algorithm was performed using ultrasound data, MUSE is
"Mente" Adverbs, Compound Interpretation and the Projection Principle.
ERIC Educational Resources Information Center
Zagona, Karen
An analysis of the structure and interpretation of Spanish adverbs ending in "-mente" focuses on the grammatical status of the constituent elements of those words. It begins by looking at the grammatical properties of "-mente" adverbs (MAs), the word-level properties of MA constituents, and the compound types and their interpretation. It is argued…
Robustness of one-dimensional viscous fluid motion under multidimensional perturbations
NASA Astrophysics Data System (ADS)
Feireisl, Eduard; Sun, Yongzhong
2015-12-01
We adapt the relative energy functional associated to the compressible Navier-Stokes system to show stability of solutions emanating from 1-D initial data with respect to multidimensional N = 2, 3 perturbations. Besides the application of the relative energy inequality as a suitable "distance" between two solutions, refined regularity estimates in Lp based Sobolev spaces are used.
ERIC Educational Resources Information Center
Alexiadou, Artemis; Stavrakaki, Stavroula
2006-01-01
In this paper, we investigate the performance of a Greek-English bilingual patient with Broca's aphasia and mild agrammatism on the placement of CP, MoodP, AspectP, and NegP-related adverbs, labeled specifier-type adverbs, and VP-related adverbs, labeled complement-type adverbs, by means of a constituent ordering task and a grammaticality judgment…
Sakurai, Atsunori; Tanimura, Yoshitaka
2011-04-28
To investigate the role of quantum effects in vibrational spectroscopies, we have carried out numerically exact calculations of linear and nonlinear response functions for an anharmonic potential system nonlinearly coupled to a harmonic oscillator bath. Although one cannot carry out the quantum calculations of the response functions with full molecular dynamics (MD) simulations for a realistic system which consists of many molecules, it is possible to grasp the essence of the quantum effects on the vibrational spectra by employing a model Hamiltonian that describes an intra- or intermolecular vibrational motion in a condensed phase. The present model fully includes vibrational relaxation, while the stochastic model often used to simulate infrared spectra does not. We have employed the reduced quantum hierarchy equations of motion approach in the Wigner space representation to deal with nonperturbative, non-Markovian, and nonsecular system-bath interactions. Taking the classical limit of the hierarchy equations of motion, we have obtained the classical equations of motion that describe the classical dynamics under the same physical conditions as in the quantum case. By comparing the classical and quantum mechanically calculated linear and multidimensional spectra, we found that the profiles of spectra for a fast modulation case were similar, but different for a slow modulation case. In both the classical and quantum cases, we identified the resonant oscillation peak in the spectra, but the quantum peak shifted to the red compared with the classical one if the potential is anharmonic. The prominent quantum effect is the 1-2 transition peak, which appears only in the quantum mechanically calculated spectra as a result of anharmonicity in the potential or nonlinearity of the system-bath coupling. While the contribution of the 1-2 transition is negligible in the fast modulation case, it becomes important in the slow modulation case as long as the amplitude of the
Adverb Code-Switching among Miami's Haitian Creole-English Second Generation
ERIC Educational Resources Information Center
Hebblethwaite, Benjamin
2010-01-01
The findings for adverbs and adverbial phrases in a naturalistic corpus of Miami Haitian Creole-English code-switching show that one language, Haitian Creole, asymmetrically supplies the grammatical frame while the other language, English, asymmetrically supplies mixed lexical categories like adverbs. Traces of code-switching with an English frame…
Acquisition of adjectives and adverbs in sentences written by hearing impaired and aphasic children.
Heward, W L; Eachus, H T
1979-01-01
The effect of an instructional package, which included modeling, reinforcement, and remedial feedback on the rate, accuracy, and topography of sentences composed by four hearing impaired and aphasic children, was examined. In a specially designed classroom, students wrote sentences describing a stimulus picture on acetate sheets placed on the stage of an overhead projector which was built into each student's desk. This arrangement provided the teacher and other students immediate and continuous visual access to each student's sentences. In a multiple baseline design across behaviors, model sentences were projected and token reinforcment and remedial feedback were made contingent upon writing correct sentences containing prenominal adjectives only, then adverbs only, then prenomial adjectives plus adverbs. During baseline all student displayed poor written language skills and seldom wrote sentences containing modifiers. When the instructional package was implemented, all students demonstrated significant increases in response rate, accuracy, and percentage of correct sentences including prenominal adjectives and adverbs.
Acquisition of adjectives and adverbs in sentences written by hearing impaired and aphasic children.
Heward, W L; Eachus, H T
1979-01-01
The effect of an instructional package, which included modeling, reinforcement, and remedial feedback on the rate, accuracy, and topography of sentences composed by four hearing impaired and aphasic children, was examined. In a specially designed classroom, students wrote sentences describing a stimulus picture on acetate sheets placed on the stage of an overhead projector which was built into each student's desk. This arrangement provided the teacher and other students immediate and continuous visual access to each student's sentences. In a multiple baseline design across behaviors, model sentences were projected and token reinforcment and remedial feedback were made contingent upon writing correct sentences containing prenominal adjectives only, then adverbs only, then prenomial adjectives plus adverbs. During baseline all student displayed poor written language skills and seldom wrote sentences containing modifiers. When the instructional package was implemented, all students demonstrated significant increases in response rate, accuracy, and percentage of correct sentences including prenominal adjectives and adverbs. PMID:92469
Alexiadou, Artemis; Stavrakaki, Stavroula
2006-02-01
In this paper, we investigate the performance of a Greek-English bilingual patient with Broca's aphasia and mild agrammatism on the placement of CP, MoodP, AspectP, and NegP-related adverbs, labeled specifier-type adverbs, and VP-related adverbs, labeled complement-type adverbs, by means of a constituent ordering task and a grammaticality judgment task. Based on the results derived by means of these two different tasks in both Greek and English, we argue that (i) the CP layer causes great difficulties to aphasic performance in both languages but it is not missing from aphasic grammar, whereas the VP layer remains intact in both languages; (ii) the MoodP, AspectP, and NegP-related adverbs cause more difficulties in English that in Greek. We attribute this to the independent differences between English and Greek that relate to properties of verbal morphology and syntactic head movement. PMID:15935462
Alexiadou, Artemis; Stavrakaki, Stavroula
2006-02-01
In this paper, we investigate the performance of a Greek-English bilingual patient with Broca's aphasia and mild agrammatism on the placement of CP, MoodP, AspectP, and NegP-related adverbs, labeled specifier-type adverbs, and VP-related adverbs, labeled complement-type adverbs, by means of a constituent ordering task and a grammaticality judgment task. Based on the results derived by means of these two different tasks in both Greek and English, we argue that (i) the CP layer causes great difficulties to aphasic performance in both languages but it is not missing from aphasic grammar, whereas the VP layer remains intact in both languages; (ii) the MoodP, AspectP, and NegP-related adverbs cause more difficulties in English that in Greek. We attribute this to the independent differences between English and Greek that relate to properties of verbal morphology and syntactic head movement.
Figure and Ground in Temporal Sentences: The Role of the Adverbs "When" and "While"
ERIC Educational Resources Information Center
De Vega, Manuel; Rinck, Mike; Diaz, Jose; Leon, Inmaculada
2007-01-01
Multiclause sentences with the temporal adverbs "while" or "when" referring to simultaneous events (e.g., "While [when] John was writing a letter, Mary comes into the room") were compared in German and Spanish. Following Talmy (2001), we assumed that the event in the main clause is the figure (F; the event to be located in time), and the event in…
ERIC Educational Resources Information Center
Pacton, Sebastien; Fayol, Michel
2003-01-01
This study examined how French third (36) and fifth (36) graders used the morphosyntactic context when they spell morphologically complex words with homophonous suffixes (/a/). Participants had to spell adverbs (/a/ transcribed ent) and present participles (/a/ transcribed ant), contrasted on the basis of their frequency, in isolation or embedded…
Zanni, Martin Thomas; Damrauer, Niels H.
2010-07-20
A multidimensional spectrometer for the infrared, visible, and ultraviolet regions of the electromagnetic spectrum, and a method for making multidimensional spectroscopic measurements in the infrared, visible, and ultraviolet regions of the electromagnetic spectrum. The multidimensional spectrometer facilitates measurements of inter- and intra-molecular interactions.
ERIC Educational Resources Information Center
Zierer, Ernesto
1971-01-01
This paper considers Spanish adjectives and the possibility of converting some adjectives into adverbs, keeping the same general significance of a sentence. The conversion of an adjective into an adverb under these circumstances can be accomplished through a transformation which can be applied to a particular logical-semantic structure. The author…
ERIC Educational Resources Information Center
Brand, Judith, Ed.
2002-01-01
This issue of Exploratorium Magazine focuses on the topic of motion. Contents include: (1) "First Word" (Zach Tobias); (2) "Cosmic Collisions" (Robert Irion); (3) "The Mobile Cell" (Karen E. Kalumuck); (4) "The Paths of Paths" (Steven Vogel); (5) "Fragments" (Pearl Tesler); (6) "Moving Pictures" (Amy Snyder); (7) "Plants on the Go" (Katharine…
ERIC Educational Resources Information Center
Criado de Val, Manuel
1973-01-01
Compares use of pronouns and adverbs in Spanish, French, Italian, Portuguese, English, German, Rumanian, and Slavic languages. Excerpted from the book Fisonomia del y de las lenguas modernas'' ( Features of Modern Languages''). (DS)
Preface: Special Topic on Multidimensional Spectroscopy
NASA Astrophysics Data System (ADS)
Mukamel, Shaul; Bakker, Huib J.
2015-06-01
Multidimensional signals are generated by subjecting molecules to sequences of short optical pulses and recording correlation plots related to the various controlled delay periods. These techniques which span all the way from the THz to the x-ray regimes provide qualitatively new structural and dynamical molecular information not available from conventional one-dimensional techniques. This issue surveys the recent experimental and theoretical progresses in this rapidly developing 20 year old field which illustrates the novel insights provided by multidimensional techniques into electronic and nuclear motions. It should serve as a valuable source for experts in the field and help introduce newcomers to this exciting and challenging branch of nonlinear spectroscopy.
Preface: Special Topic on Multidimensional Spectroscopy
Mukamel, Shaul; Bakker, Huib J.
2015-06-07
Multidimensional signals are generated by subjecting molecules to sequences of short optical pulses and recording correlation plots related to the various controlled delay periods. These techniques which span all the way from the THz to the x-ray regimes provide qualitatively new structural and dynamical molecular information not available from conventional one-dimensional techniques. This issue surveys the recent experimental and theoretical progresses in this rapidly developing 20 year old field which illustrates the novel insights provided by multidimensional techniques into electronic and nuclear motions. It should serve as a valuable source for experts in the field and help introduce newcomers to this exciting and challenging branch of nonlinear spectroscopy.
Preface: Special Topic on Multidimensional Spectroscopy.
Mukamel, Shaul; Bakker, Huib J
2015-06-01
Multidimensional signals are generated by subjecting molecules to sequences of short optical pulses and recording correlation plots related to the various controlled delay periods. These techniques which span all the way from the THz to the x-ray regimes provide qualitatively new structural and dynamical molecular information not available from conventional one-dimensional techniques. This issue surveys the recent experimental and theoretical progresses in this rapidly developing 20 year old field which illustrates the novel insights provided by multidimensional techniques into electronic and nuclear motions. It should serve as a valuable source for experts in the field and help introduce newcomers to this exciting and challenging branch of nonlinear spectroscopy.
Multidimensional Risk Analysis: MRISK
NASA Technical Reports Server (NTRS)
McCollum, Raymond; Brown, Douglas; O'Shea, Sarah Beth; Reith, William; Rabulan, Jennifer; Melrose, Graeme
2015-01-01
Multidimensional Risk (MRISK) calculates the combined multidimensional score using Mahalanobis distance. MRISK accounts for covariance between consequence dimensions, which de-conflicts the interdependencies of consequence dimensions, providing a clearer depiction of risks. Additionally, in the event the dimensions are not correlated, Mahalanobis distance reduces to Euclidean distance normalized by the variance and, therefore, represents the most flexible and optimal method to combine dimensions. MRISK is currently being used in NASA's Environmentally Responsible Aviation (ERA) project o assess risk and prioritize scarce resources.
Multidimensional spectral load balancing
Hendrickson, B.; Leland, R.
1993-01-01
We describe an algorithm for the static load balancing of scientific computations that generalizes and improves upon spectral bisection. Through a novel use of multiple eigenvectors, our new spectral algorithm can divide a computation into 4 or 8 pieces at once. These multidimensional spectral partitioning algorithms generate balanced partitions that have lower communication overhead and are less expensive to compute than those produced by spectral bisection. In addition, they automatically work to minimize message contention on a hypercube or mesh architecture. These spectral partitions are further improved by a multidimensional generalization of the Kernighan-Lin graph partitioning algorithm. Results on several computational grids are given and compared with other popular methods.
Preface: Special Topic on Multidimensional Spectroscopy.
Mukamel, Shaul; Bakker, Huib J
2015-06-01
Multidimensional signals are generated by subjecting molecules to sequences of short optical pulses and recording correlation plots related to the various controlled delay periods. These techniques which span all the way from the THz to the x-ray regimes provide qualitatively new structural and dynamical molecular information not available from conventional one-dimensional techniques. This issue surveys the recent experimental and theoretical progresses in this rapidly developing 20 year old field which illustrates the novel insights provided by multidimensional techniques into electronic and nuclear motions. It should serve as a valuable source for experts in the field and help introduce newcomers to this exciting and challenging branch of nonlinear spectroscopy. PMID:26049418
Multidimensional spectroscopy of photoreactivity
Ruetzel, Stefan; Diekmann, Meike; Nuernberger, Patrick; Walter, Christof; Engels, Bernd; Brixner, Tobias
2014-01-01
Coherent multidimensional electronic spectroscopy is commonly used to investigate photophysical phenomena such as light harvesting in photosynthesis in which the system returns back to its ground state after energy transfer. By contrast, we introduce multidimensional spectroscopy to study ultrafast photochemical processes in which the investigated molecule changes permanently. Exemplarily, the emergence in 2D and 3D spectra of a cross-peak between reactant and product reveals the cis–trans photoisomerization of merocyanine isomers. These compounds have applications in organic photovoltaics and optical data storage. Cross-peak oscillations originate from a vibrational wave packet in the electronically excited state of the photoproduct. This concept isolates the isomerization dynamics along different vibrational coordinates assigned by quantum-chemical calculations, and is applicable to determine chemical dynamics in complex photoreactive networks. PMID:24639540
Multidimensional radar picture
NASA Astrophysics Data System (ADS)
Waz, Mariusz
2010-05-01
In marine navigation systems, the three-dimensional (3D) visualization is often and often used. Echosonders and sonars working in hydroacustic systems can present pictures in three dimensions. Currently, vector maps also offer 3D presentation. This presentation is used in aviation and underwater navigation. In the nearest future three-dimensional presentation may be obligatory presentation in displays of navigation systems. A part of these systems work with radar and communicates with it transmitting data in a digital form. 3D presentation of radar picture require a new technology to develop. In the first step it is necessary to compile digital form of radar signal. The modern navigation radar do not present data in three-dimensional form. Progress in technology of digital signal processing make it possible to create multidimensional radar pictures. For instance, the RSC (Radar Scan Converter) - digital radar picture recording and transforming tool can be used to create new picture online. Using RSC and techniques of modern computer graphics multidimensional radar pictures can be generated. The radar pictures mentioned should be readable for ECDIS. The paper presents a method for generating multidimensional radar picture from original signal coming from radar receiver.
Ultrafast Multidimensional Laplace NMR Using a Single-Sided Magnet.
King, Jared N; Lee, Vanessa J; Ahola, Susanna; Telkki, Ville-Veikko; Meldrum, Tyler
2016-04-11
Laplace NMR (LNMR) consists of relaxation and diffusion measurements providing detailed information about molecular motion and interaction. Here we demonstrate that ultrafast single- and multidimensional LNMR experiments, based on spatial encoding, are viable with low-field, single-sided magnets with an inhomogeneous magnetic field. This approach shortens the experiment time by one to two orders of magnitude relative to traditional experiments, and increases the sensitivity per unit time by a factor of three. The reduction of time required to collect multidimensional data opens significant prospects for mobile chemical analysis using NMR. Particularly tantalizing is future use of hyperpolarization to increase sensitivity by orders of magnitude, allowed by single-scan approach.
Multidimensional sexual perfectionism.
Stoeber, Joachim; Harvey, Laura N; Almeida, Isabel; Lyons, Emma
2013-11-01
Perfectionism is a multidimensional personality characteristic that can affect all areas of life. This article presents the first systematic investigation of multidimensional perfectionism in the domain of sexuality exploring the unique relationships that different forms of sexual perfectionism show with positive and negative aspects of sexuality. A sample of 272 university students (52 male, 220 female) completed measures of four forms of sexual perfectionism: self-oriented, partner-oriented, partner-prescribed, and socially prescribed. In addition, they completed measures of sexual esteem, sexual self-efficacy, sexual optimism, sex life satisfaction (capturing positive aspects of sexuality) and sexual problem self-blame, sexual anxiety, sexual depression, and negative sexual perfectionism cognitions during sex (capturing negative aspects). Results showed unique patterns of relationships for the four forms of sexual perfectionism, suggesting that partner-prescribed and socially prescribed sexual perfectionism are maladaptive forms of sexual perfectionism associated with negative aspects of sexuality whereas self-oriented and partner-oriented sexual perfectionism emerged as ambivalent forms associated with positive and negative aspects. PMID:23842783
Theta vocabulary II. Multidimensional case
NASA Astrophysics Data System (ADS)
Kharchev, S.; Zabrodin, A.
2016-06-01
It is shown that the Jacobi and Riemann identities of degree four for the multidimensional theta functions as well as the Weierstrass identities emerge as algebraic consequences of the fundamental multidimensional binary identities connecting the theta functions with Riemann matrices τ and 2 τ.
Multidimensional Perfectionism and the Self
ERIC Educational Resources Information Center
Ward, Andrew M.; Ashby, Jeffrey S.
2008-01-01
This study examined multidimensional perfectionism and self-development. Two hundred seventy-one undergraduates completed a measure of multidimensional perfectionism and two Kohutian measures designed to measure aspects of self-development including social connectedness, social assurance, goal instability (idealization), and grandiosity. The…
Modeling, calculating, and analyzing multidimensional vibrational spectroscopies.
Tanimura, Yoshitaka; Ishizaki, Akihito
2009-09-15
Spectral line shapes in a condensed phase contain information from various dynamic processes that modulate the transition energy, such as microscopic dynamics, inter- and intramolecular couplings, and solvent dynamics. Because nonlinear response functions are sensitive to the complex dynamics of chemical processes, multidimensional vibrational spectroscopies can separate these processes. In multidimensional vibrational spectroscopy, the nonlinear response functions of a molecular dipole or polarizability are measured using ultrashort pulses to monitor inter- and intramolecular vibrational motions. Because a complex profile of such signals depends on the many dynamic and structural aspects of a molecular system, researchers would like to have a theoretical understanding of these phenomena. In this Account, we explore and describe the roles of different physical phenomena that arise from the peculiarities of the system-bath coupling in multidimensional spectra. We also present simple analytical expressions for a weakly coupled multimode Brownian system, which we use to analyze the results obtained by the experiments and simulations. To calculate the nonlinear optical response, researchers commonly use a particular form of a system Hamiltonian fit to the experimental results. The optical responses of molecular vibrational motions have been studied in either an oscillator model or a vibration energy state model. In principle, both models should give the same results as long as the energy states are chosen to be the eigenstates of the oscillator model. The energy state model can provide a simple description of nonlinear optical processes because the diagrammatic Liouville space theory that developed in the electronically resonant spectroscopies can easily handle three or four energy states involved in high-frequency vibrations. However, the energy state model breaks down if we include the thermal excitation and relaxation processes in the dynamics to put the system in a
Multidimensional persistence in biomolecular data
Xia, Kelin; Wei, Guo-Wei
2015-01-01
Persistent homology has emerged as a popular technique for the topological simplification of big data, including biomolecular data. Multidimensional persistence bears considerable promise to bridge the gap between geometry and topology. However, its practical and robust construction has been a challenge. We introduce two families of multidimensional persistence, namely pseudo-multidimensional persistence and multiscale multidimensional persistence. The former is generated via the repeated applications of persistent homology filtration to high dimensional data, such as results from molecular dynamics or partial differential equations. The latter is constructed via isotropic and anisotropic scales that create new simiplicial complexes and associated topological spaces. The utility, robustness and efficiency of the proposed topological methods are demonstrated via protein folding, protein flexibility analysis, the topological denoising of cryo-electron microscopy data, and the scale dependence of nano particles. Topological transition between partial folded and unfolded proteins has been observed in multidimensional persistence. The separation between noise topological signatures and molecular topological fingerprints is achieved by the Laplace-Beltrami flow. The multiscale multidimensional persistent homology reveals relative local features in Betti-0 invariants and the relatively global characteristics of Betti-1 and Betti-2 invariants. PMID:26032339
Multidimensional Electronic Spectroscopy of Photochemical Reactions.
Nuernberger, Patrick; Ruetzel, Stefan; Brixner, Tobias
2015-09-21
Coherent multidimensional electronic spectroscopy can be employed to unravel various channels in molecular chemical reactions. This approach is thus not limited to analysis of energy transfer or charge transfer (i.e. processes from photophysics), but can also be employed in situations where the investigated system undergoes permanent structural changes (i.e. in photochemistry). Photochemical model reactions are discussed by using the example of merocyanine/spiropyran-based molecular switches, which show a rich variety of reaction channels, in particular ring opening and ring closing, cis-trans isomerization, coherent vibrational wave-packet motion, radical ion formation, and population relaxation. Using pump-probe, pump-repump-probe, coherent two-dimensional and three-dimensional, triggered-exchange 2D, and quantum-control spectroscopy, we gain intuitive pictures on which product emerges from which reactant and which reactive molecular modes are associated. PMID:26382095
Multidimensional persistence in biomolecular data.
Xia, Kelin; Wei, Guo-Wei
2015-07-30
Persistent homology has emerged as a popular technique for the topological simplification of big data, including biomolecular data. Multidimensional persistence bears considerable promise to bridge the gap between geometry and topology. However, its practical and robust construction has been a challenge. We introduce two families of multidimensional persistence, namely pseudomultidimensional persistence and multiscale multidimensional persistence. The former is generated via the repeated applications of persistent homology filtration to high-dimensional data, such as results from molecular dynamics or partial differential equations. The latter is constructed via isotropic and anisotropic scales that create new simiplicial complexes and associated topological spaces. The utility, robustness, and efficiency of the proposed topological methods are demonstrated via protein folding, protein flexibility analysis, the topological denoising of cryoelectron microscopy data, and the scale dependence of nanoparticles. Topological transition between partial folded and unfolded proteins has been observed in multidimensional persistence. The separation between noise topological signatures and molecular topological fingerprints is achieved by the Laplace-Beltrami flow. The multiscale multidimensional persistent homology reveals relative local features in Betti-0 invariants and the relatively global characteristics of Betti-1 and Betti-2 invariants.
Generalized multidimensional dynamic allocation method.
Lebowitsch, Jonathan; Ge, Yan; Young, Benjamin; Hu, Feifang
2012-12-10
Dynamic allocation has received considerable attention since it was first proposed in the 1970s as an alternative means of allocating treatments in clinical trials which helps to secure the balance of prognostic factors across treatment groups. The purpose of this paper is to present a generalized multidimensional dynamic allocation method that simultaneously balances treatment assignments at three key levels: within the overall study, within each level of each prognostic factor, and within each stratum, that is, combination of levels of different factors Further it offers capabilities for unbalanced and adaptive designs for trials. The treatment balancing performance of the proposed method is investigated through simulations which compare multidimensional dynamic allocation with traditional stratified block randomization and the Pocock-Simon method. On the basis of these results, we conclude that this generalized multidimensional dynamic allocation method is an improvement over conventional dynamic allocation methods and is flexible enough to be applied for most trial settings including Phases I, II and III trials.
On the Need for Multidimensional Stirling Simulations
NASA Technical Reports Server (NTRS)
Dyson, Rodger W.; Wilson, Scott D.; Tew, Roy C.; Demko, Rikako
2005-01-01
Given the cost and complication of simulating Stirling convertors, do we really need multidimensional modeling when one-dimensional capabilities exist? This paper provides a comprehensive description of when and why multidimensional simulation is needed.
Ultrafast Multidimensional Laplace NMR Using a Single-Sided Magnet.
King, Jared N; Lee, Vanessa J; Ahola, Susanna; Telkki, Ville-Veikko; Meldrum, Tyler
2016-04-11
Laplace NMR (LNMR) consists of relaxation and diffusion measurements providing detailed information about molecular motion and interaction. Here we demonstrate that ultrafast single- and multidimensional LNMR experiments, based on spatial encoding, are viable with low-field, single-sided magnets with an inhomogeneous magnetic field. This approach shortens the experiment time by one to two orders of magnitude relative to traditional experiments, and increases the sensitivity per unit time by a factor of three. The reduction of time required to collect multidimensional data opens significant prospects for mobile chemical analysis using NMR. Particularly tantalizing is future use of hyperpolarization to increase sensitivity by orders of magnitude, allowed by single-scan approach. PMID:26960011
Recycling Behavior: A Multidimensional Approach
ERIC Educational Resources Information Center
Meneses, Gonzalo Diaz; Palacio, Asuncion Beerli
2005-01-01
This work centers on the study of consumer recycling roles to examine the sociodemographic and psychographic profile of the distribution of recycling tasks and roles within the household. With this aim in mind, an empirical work was carried out, the results of which suggest that recycling behavior is multidimensional and comprises the undertaking…
A Multidimensional Software Engineering Course
ERIC Educational Resources Information Center
Barzilay, O.; Hazzan, O.; Yehudai, A.
2009-01-01
Software engineering (SE) is a multidimensional field that involves activities in various areas and disciplines, such as computer science, project management, and system engineering. Though modern SE curricula include designated courses that address these various subjects, an advanced summary course that synthesizes them is still missing. Such a…
Mixing Study in a Multi-dimensional Motion Mixer
NASA Astrophysics Data System (ADS)
Shah, R.; Manickam, S. S.; Tomei, J.; Bergman, T. L.; Chaudhuri, B.
2009-06-01
Mixing is an important but poorly understood aspect in petrochemical, food, ceramics, fertilizer and pharmaceutical processing and manufacturing. Deliberate mixing of granular solids is an essential operation in the production of industrial powder products usually constituted from different ingredients. The knowledge of particle flow and mixing in a blender is critical to optimize the design and operation. Since performance of the product depends on blend homogeneity, the consequence of variability can be detrimental. A common approach to powder mixing is to use a tumbling blender, which is essentially a hollow vessel horizontally attached to a rotating shaft. This single axis rotary blender is one of the most common batch mixers among in industry, and also finds use in myriad of application as dryers, kilns, coaters, mills and granulators. In most of the rotary mixers the radial convection is faster than axial dispersion transport. This slow dispersive process hinders mixing performance in many blending, drying and coating applications. A double cone mixer is designed and fabricated which rotates around two axes, causing axial mixing competitive to its radial counterpart. Discrete Element Method (DEM) based numerical model is developed to simulate the granular flow within the mixer. Digitally recorded mixing states from experiments are used to fine tune the numerical model. Discrete pocket samplers are also used in the experiments to quantify the characteristics of mixing. A parametric study of the effect of vessel speeds, relative rotational speed (between two axes of rotation), on the granular mixing is investigated by experiments and numerical simulation. Incorporation of dual axis rotation enhances axial mixing by 60 to 85% in comparison to single axis rotation.
... people traveling by car, train, airplanes and especially boats. Motion sickness can start suddenly, with a queasy ... motion sickness. For example, down below on a boat, your inner ear senses motion, but your eyes ...
A multidimensional pendulum in a nonconservative force field under the presence of linear damping
NASA Astrophysics Data System (ADS)
Shamolin, M. V.
2016-09-01
A nonconservative force field in the dynamics of a multidimensional solid is constructed according to the results from the dynamics of real solids occurring in the force field of the action of the medium. In this case, it becomes possible to generalize the equations of motion of a multidimensional solid in a similarly constructed field of forces and to obtain a complete list of, generally speaking, transcendental first integrals expressed through a finite combination of elementary functions. In the study, the integrability in elementary functions is shown for the simultaneous equations of motion of a dynamically symmetric fixed multidimensional solid under the action of a nonconservative pair of forces in the presence of the linear damping moment (the additional dependence of the force field on the tensor of angular velocity of the solid).
A Multidimensional Analysis of Content Preferences for Leisure-Time Media.
ERIC Educational Resources Information Center
Hirschman, Elizabeth C.
1985-01-01
This study examined the structure underlying preferences for content in books, motion pictures, and television programs. Multidimensionally scaled correlations revealed two dimensions; entertainment-diversion versus aesthetic-intellectual preferences and expressive versus instrumental behavior. Findings are discussed. (Author/MT)
Deterministic multidimensional nonuniform gap sampling.
Worley, Bradley; Powers, Robert
2015-12-01
Born from empirical observations in nonuniformly sampled multidimensional NMR data relating to gaps between sampled points, the Poisson-gap sampling method has enjoyed widespread use in biomolecular NMR. While the majority of nonuniform sampling schemes are fully randomly drawn from probability densities that vary over a Nyquist grid, the Poisson-gap scheme employs constrained random deviates to minimize the gaps between sampled grid points. We describe a deterministic gap sampling method, based on the average behavior of Poisson-gap sampling, which performs comparably to its random counterpart with the additional benefit of completely deterministic behavior. We also introduce a general algorithm for multidimensional nonuniform sampling based on a gap equation, and apply it to yield a deterministic sampling scheme that combines burst-mode sampling features with those of Poisson-gap schemes. Finally, we derive a relationship between stochastic gap equations and the expectation value of their sampling probability densities.
Deterministic multidimensional nonuniform gap sampling
NASA Astrophysics Data System (ADS)
Worley, Bradley; Powers, Robert
2015-12-01
Born from empirical observations in nonuniformly sampled multidimensional NMR data relating to gaps between sampled points, the Poisson-gap sampling method has enjoyed widespread use in biomolecular NMR. While the majority of nonuniform sampling schemes are fully randomly drawn from probability densities that vary over a Nyquist grid, the Poisson-gap scheme employs constrained random deviates to minimize the gaps between sampled grid points. We describe a deterministic gap sampling method, based on the average behavior of Poisson-gap sampling, which performs comparably to its random counterpart with the additional benefit of completely deterministic behavior. We also introduce a general algorithm for multidimensional nonuniform sampling based on a gap equation, and apply it to yield a deterministic sampling scheme that combines burst-mode sampling features with those of Poisson-gap schemes. Finally, we derive a relationship between stochastic gap equations and the expectation value of their sampling probability densities.
Multidimensional theory of protein folding
NASA Astrophysics Data System (ADS)
Itoh, Kazuhito; Sasai, Masaki
2009-04-01
Theory of multidimensional representation of free energy surface of protein folding is developed by adopting structural order parameters of multiple regions in protein as multiple coordinates. Various scenarios of folding are classified in terms of cooperativity within individual regions and interactions among multiple regions and thus obtained classification is used to analyze the folding process of several example proteins. Ribosomal protein S6, src-SH3 domain, CheY, barnase, and BBL domain are analyzed with the two-dimensional representation by using a structure-based Hamiltonian model. The extension to the higher dimensional representation leads to the finer description of the folding process. Barnase, NtrC, and an ankyrin repeat protein are examined with the three-dimensional representation. The multidimensional representation allows us to directly address questions on folding pathways, intermediates, and transition states.
Multidimensional bioseparation with modular microfluidics
Chirica, Gabriela S.; Renzi, Ronald F.
2013-08-27
A multidimensional chemical separation and analysis system is described including a prototyping platform and modular microfluidic components capable of rapid and convenient assembly, alteration and disassembly of numerous candidate separation systems. Partial or total computer control of the separation system is possible. Single or multiple alternative processing trains can be tested, optimized and/or run in parallel. Examples related to the separation and analysis of human bodily fluids are given.
Cuba: Multidimensional numerical integration library
NASA Astrophysics Data System (ADS)
Hahn, Thomas
2016-08-01
The Cuba library offers four independent routines for multidimensional numerical integration: Vegas, Suave, Divonne, and Cuhre. The four algorithms work by very different methods, and can integrate vector integrands and have very similar Fortran, C/C++, and Mathematica interfaces. Their invocation is very similar, making it easy to cross-check by substituting one method by another. For further safeguarding, the output is supplemented by a chi-square probability which quantifies the reliability of the error estimate.
Lu, Maolin; Lu, H Peter
2014-10-16
Conformational motions of proteins are highly dynamic and intrinsically complex. To capture the temporal and spatial complexity of conformational motions and further to understand their roles in protein functions, an attempt is made to probe multidimensional conformational dynamics of proteins besides the typical one-dimensional FRET coordinate or the projected conformational motions on the one-dimensional FRET coordinate. T4 lysozyme hinge-bending motions between two domains along α-helix have been probed by single-molecule FRET. Nevertheless, the domain motions of T4 lysozyme are rather complex involving multiple coupled nuclear coordinates and most likely contain motions besides hinge-bending. It is highly likely that the multiple dimensional protein conformational motions beyond the typical enzymatic hinged-bending motions have profound impact on overall enzymatic functions. In this report, we have developed a single-molecule multiparameter photon stamping spectroscopy integrating fluorescence anisotropy, FRET, and fluorescence lifetime. This spectroscopic approach enables simultaneous observations of both FRET-related site-to-site conformational dynamics and molecular rotational (or orientational) motions of individual Cy3-Cy5 labeled T4 lysozyme molecules. We have further observed wide-distributed rotational flexibility along orientation coordinates by recording fluorescence anisotropy and simultaneously identified multiple intermediate conformational states along FRET coordinate by monitoring time-dependent donor lifetime, presenting a whole picture of multidimensional conformational dynamics in the process of T4 lysozyme open-close hinge-bending enzymatic turnover motions under enzymatic reaction conditions. By analyzing the autocorrelation functions of both lifetime and anisotropy trajectories, we have also observed the dynamic and static inhomogeneity of T4 lysozyme multidimensional conformational fluctuation dynamics, providing a fundamental
Multidimensional quantum tunneling in the Schwinger effect
NASA Astrophysics Data System (ADS)
Dumlu, Cesim K.
2016-03-01
We study the Schwinger effect, in which the external field having a spatiotemporal profile creates electron-positron pairs via multidimensional quantum tunneling. Our treatment is based on the trace formula for the QED effective action, whose imaginary part is represented by a sum over complex worldline solutions. The worldlines are multiperiodic, and the periods of motion collectively depend on the strength of spatial and temporal inhomogeneity. We argue that the classical action that leads to the correct tunneling amplitude must take into account both the full period, T ˜ and the first fundamental period, T1. In view of this argument we investigate pair production in an exponentially damped sinusoidal field and find that the initial momenta for multiperiodic trajectories lie on parabolic curves, such that on each curve the ratio T ˜/T1 stays uniform. Evaluation of the tunneling amplitude using these trajectories shows that vacuum decay rate is reduced by an order of magnitude, with respect to the purely time-dependent case, due to the presence of magnetic field.
Measures for a multidimensional multiverse
NASA Astrophysics Data System (ADS)
Chung, Hyeyoun
2015-04-01
We explore the phenomenological implications of generalizing the causal patch and fat geodesic measures to a multidimensional multiverse, where the vacua can have differing numbers of large dimensions. We consider a simple model in which the vacua are nucleated from a D -dimensional parent spacetime through dynamical compactification of the extra dimensions, and compute the geometric contribution to the probability distribution of observations within the multiverse for each measure. We then study how the shape of this probability distribution depends on the time scales for the existence of observers, for vacuum domination, and for curvature domination (tobs,tΛ , and tc, respectively.) In this work we restrict ourselves to bubbles with positive cosmological constant, Λ . We find that in the case of the causal patch cutoff, when the bubble universes have p +1 large spatial dimensions with p ≥2 , the shape of the probability distribution is such that we obtain the coincidence of time scales tobs˜tΛ˜tc . Moreover, the size of the cosmological constant is related to the size of the landscape. However, the exact shape of the probability distribution is different in the case p =2 , compared to p ≥3 . In the case of the fat geodesic measure, the result is even more robust: the shape of the probability distribution is the same for all p ≥2 , and we once again obtain the coincidence tobs˜tΛ˜tc . These results require only very mild conditions on the prior probability of the distribution of vacua in the landscape. Our work shows that the observed double coincidence of time scales is a robust prediction even when the multiverse is generalized to be multidimensional; that this coincidence is not a consequence of our particular Universe being (3 +1 )-dimensional; and that this observable cannot be used to preferentially select one measure over another in a multidimensional multiverse.
Gordon, R.G. )
1991-01-01
The motion of tectonic plates on the earth is characterized in a critical review of U.S. research from the period 1987-1990. Topics addressed include the NUVEL-1 global model of current plate motions, diffuse plate boundaries and the oceanic lithosphere, the relation between plate motions and distributed deformations, accelerations and the steadiness of plate motions, the distribution of current Pacific-North America motion across western North America and its margin, plate reconstructions and their uncertainties, hotspots, and plate dynamics. A comprehensive bibliography is provided. 126 refs.
On Compensation in Multidimensional Response Modeling
ERIC Educational Resources Information Center
van der Linden, Wim J.
2012-01-01
The issue of compensation in multidimensional response modeling is addressed. We show that multidimensional response models are compensatory in their ability parameters if and only if they are monotone. In addition, a minimal set of assumptions is presented under which the MLEs of the ability parameters are also compensatory. In a recent series of…
Multidimensional Scaling of Classroom Interaction Data.
ERIC Educational Resources Information Center
Rumery, Robert E.; Hartnett, Barbara M.
The use of Kruskal's nonmetric multidimensional scaling model for analysis of classroom interaction data is discussed. Four distance models are proposed which lead to multidimensional representation of single sequences, sets of sequences, and behavior categories using symmetric and conditional proximity options of the model. Results of application…
Sumi, Chikayoshi
2008-01-01
Two new methods of measuring a multidimensional displacement vector using an instantaneous ultrasound signal phase are described, i.e., the multidimensional autocorrelation method (MAM) and multidimensional Doppler method (MDM). A high measurement accuracy is achieved by combining either method with the lateral Gaussian envelope cosine modulation method (LGECMM) or multidirectional synthetic aperture method (MDSAM). Measurement accuracy is evaluated using simulated noisy echo data. Both methods yield accurate measurements comparable to that of our previously developed cross-spectrum phase gradient method (MCSPGM); however, they require less computational time (the order, MDM < MAM approximate, equals MCSPGM) and would provide realtime measurements. Moreover, comparisons of LGECMM and MDSAM performed by geometrical evaluations clarifies that LGECMM has potentials to yield more accurate measurements with less computational time. Both MAM and MDM can be applied to the measurement of tissue strain, blood flow, sonar data, and other target motions.
Multidimensional Adaptation in MAS Organizations.
Alberola, Juan M; Julian, Vicente; Garcia-Fornes, Ana
2013-04-01
Organization adaptation requires determining the consequences of applying changes not only in terms of the benefits provided but also measuring the adaptation costs as well as the impact that these changes have on all of the components of the organization. In this paper, we provide an approach for adaptation in multiagent systems based on a multidimensional transition deliberation mechanism (MTDM). This approach considers transitions in multiple dimensions and is aimed at obtaining the adaptation with the highest potential for improvement in utility based on the costs of adaptation. The approach provides an accurate measurement of the impact of the adaptation since it determines the organization that is to be transitioned to as well as the changes required to carry out this transition. We show an example of adaptation in a service provider network environment in order to demonstrate that the measurement of the adaptation consequences taken by the MTDM improves the organization performance more than the other approaches.
Golding, J F
2016-01-01
Over 2000 years ago the Greek physician Hippocrates wrote, "sailing on the sea proves that motion disorders the body." Indeed, the word "nausea" derives from the Greek root word naus, hence "nautical," meaning a ship. The primary signs and symptoms of motion sickness are nausea and vomiting. Motion sickness can be provoked by a wide variety of transport environments, including land, sea, air, and space. The recent introduction of new visual technologies may expose more of the population to visually induced motion sickness. This chapter describes the signs and symptoms of motion sickness and different types of provocative stimuli. The "how" of motion sickness (i.e., the mechanism) is generally accepted to involve sensory conflict, for which the evidence is reviewed. New observations concern the identification of putative "sensory conflict" neurons and the underlying brain mechanisms. But what reason or purpose does motion sickness serve, if any? This is the "why" of motion sickness, which is analyzed from both evolutionary and nonfunctional maladaptive theoretic perspectives. Individual differences in susceptibility are great in the normal population and predictors are reviewed. Motion sickness susceptibility also varies dramatically between special groups of patients, including those with different types of vestibular disease and in migraineurs. Finally, the efficacy and relative advantages and disadvantages of various behavioral and pharmacologic countermeasures are evaluated. PMID:27638085
NASA Astrophysics Data System (ADS)
Lavenda, B. H.
1985-02-01
Brownian motion, the doubly random motion of small particles suspended in a liquid due to molecular collisions, and its implications and applications in the history of modern science are discussed. Topics examined include probabilistic phenomena, the kinetic theory of gases, Einstein's atomic theory of Brownian motion, particle displacement, diffusion measurements, the determination of the mass of the atom and of Avogadro's number, the statistical mechanics of thermodynamics, nonequilibrium systems, Langevin's equation of motion, time-reversed evolution, mathematical analogies, and applications in economics and radio navigation. Diagrams and drawings are provided.
NASA Astrophysics Data System (ADS)
Wright, John C.
2016-10-01
Spectroscopy is a dominant measurement methodology because it resolves molecular level details over a wide concentration range. Its limitations, however, become challenged when applied to complex materials. Coherent multidimensional spectroscopy (CMDS) is the optical analogue of multidimensional NMR and like NMR, its multidimensionality promises to increase the spectral selectivity of vibrational and electronic spectroscopy. This article explores whether this promise can make CMDS a dominant spectroscopic method throughout the sciences. In order for CMDS to become a dominant methodology, it must create multidimensional spectral fingerprints that provide the selectivity required for probing complex samples. Pump-CMDS probe methods separate the pump's measurement of dynamics from a multidimensional and selective probe. Fully coherent CMDS methods are ideal multidimensional probes because they avoid relaxation effects, spectrally isolate the output signals, and provide unique and invariant spectral signatures using any combination of vibrational and electronic quantum states.
Random Effects Diagonal Metric Multidimensional Scaling Models.
ERIC Educational Resources Information Center
Clarkson, Douglas B.; Gonzalez, Richard
2001-01-01
Defines a random effects diagonal metric multidimensional scaling model, gives its computational algorithms, describes researchers' experiences with these algorithms, and provides an illustration of the use of the model and algorithms. (Author/SLD)
Systems of Values and Their Multidimensional Representations
ERIC Educational Resources Information Center
Jones, Russell A.; And Others
1978-01-01
Values were elicited spontaneously from a sample of undergraduates and adults attending college, and were compared to Rokeach's terminal and instrumental values. Multidimensional scaling revealed a simpler structure among spontaneously mentioned values than Rokeach's values. (JKS)
VH-1: Multidimensional ideal compressible hydrodynamics code
NASA Astrophysics Data System (ADS)
Hawley, John; Blondin, John; Lindahl, Greg; Lufkin, Eric
2012-04-01
VH-1 is a multidimensional ideal compressible hydrodynamics code written in FORTRAN for use on any computing platform, from desktop workstations to supercomputers. It uses a Lagrangian remap version of the Piecewise Parabolic Method developed by Paul Woodward and Phil Colella in their 1984 paper. VH-1 comes in a variety of versions, from a simple one-dimensional serial variant to a multi-dimensional version scalable to thousands of processors.
Multidimensional stochastic approximation Monte Carlo.
Zablotskiy, Sergey V; Ivanov, Victor A; Paul, Wolfgang
2016-06-01
Stochastic Approximation Monte Carlo (SAMC) has been established as a mathematically founded powerful flat-histogram Monte Carlo method, used to determine the density of states, g(E), of a model system. We show here how it can be generalized for the determination of multidimensional probability distributions (or equivalently densities of states) of macroscopic or mesoscopic variables defined on the space of microstates of a statistical mechanical system. This establishes this method as a systematic way for coarse graining a model system, or, in other words, for performing a renormalization group step on a model. We discuss the formulation of the Kadanoff block spin transformation and the coarse-graining procedure for polymer models in this language. We also apply it to a standard case in the literature of two-dimensional densities of states, where two competing energetic effects are present g(E_{1},E_{2}). We show when and why care has to be exercised when obtaining the microcanonical density of states g(E_{1}+E_{2}) from g(E_{1},E_{2}). PMID:27415383
Multidimensionally encoded magnetic resonance imaging.
Lin, Fa-Hsuan
2013-07-01
Magnetic resonance imaging (MRI) typically achieves spatial encoding by measuring the projection of a q-dimensional object over q-dimensional spatial bases created by linear spatial encoding magnetic fields (SEMs). Recently, imaging strategies using nonlinear SEMs have demonstrated potential advantages for reconstructing images with higher spatiotemporal resolution and reducing peripheral nerve stimulation. In practice, nonlinear SEMs and linear SEMs can be used jointly to further improve the image reconstruction performance. Here, we propose the multidimensionally encoded (MDE) MRI to map a q-dimensional object onto a p-dimensional encoding space where p > q. MDE MRI is a theoretical framework linking imaging strategies using linear and nonlinear SEMs. Using a system of eight surface SEM coils with an eight-channel radiofrequency coil array, we demonstrate the five-dimensional MDE MRI for a two-dimensional object as a further generalization of PatLoc imaging and O-space imaging. We also present a method of optimizing spatial bases in MDE MRI. Results show that MDE MRI with a higher dimensional encoding space can reconstruct images more efficiently and with a smaller reconstruction error when the k-space sampling distribution and the number of samples are controlled.
Multidimensional stochastic approximation Monte Carlo
NASA Astrophysics Data System (ADS)
Zablotskiy, Sergey V.; Ivanov, Victor A.; Paul, Wolfgang
2016-06-01
Stochastic Approximation Monte Carlo (SAMC) has been established as a mathematically founded powerful flat-histogram Monte Carlo method, used to determine the density of states, g (E ) , of a model system. We show here how it can be generalized for the determination of multidimensional probability distributions (or equivalently densities of states) of macroscopic or mesoscopic variables defined on the space of microstates of a statistical mechanical system. This establishes this method as a systematic way for coarse graining a model system, or, in other words, for performing a renormalization group step on a model. We discuss the formulation of the Kadanoff block spin transformation and the coarse-graining procedure for polymer models in this language. We also apply it to a standard case in the literature of two-dimensional densities of states, where two competing energetic effects are present g (E1,E2) . We show when and why care has to be exercised when obtaining the microcanonical density of states g (E1+E2) from g (E1,E2) .
Multidimensional Modeling of Nova Outbursts
NASA Astrophysics Data System (ADS)
José, J.
2014-12-01
Classical novae repeatedly eject ˜10-4-10-5 M⊙ enriched in nuclear-processed material relative to solar abundances, recurring on intervals of decades to tens of millennia. They are probably the main sources of Galactic 15N, 17O and 13C. The origin of the large enhancements and inhomogeneous distribution of these species observed in high-resolution spectra of ejected nova shells has, however, remained unexplained for almost 50 years. Several mechanisms, including mixing by diffusion, shear or resonant gravity waves, have been proposed in the framework of one-dimensional or two-dimensional simulations, but none has proven successful because convective mixing can only be modeled accurately in three-dimensions. This review focuses on multidimensional modeling of nova explosions, with emphasis on mixing at the core-envelope interface. Examples of buoyant fingering driving vortices from the Kelvin-Helmholtz instability, leading to enrichment of the accreted envelope with material from the outer white dwarf core, will be described. This mixing mechanism naturally accounts for large-scale chemical inhomogeneities. Preliminary simulations of the interaction between the nova ejecta and the secondary star will also be outlined.
ERIC Educational Resources Information Center
Van Deun, Katrijn; Heiser, Willem J.; Delbeke, Luc
2007-01-01
A multidimensional unfolding technique that is not prone to degenerate solutions and is based on multidimensional scaling of a complete data matrix is proposed: distance information about the unfolding data and about the distances both among judges and among objects is included in the complete matrix. The latter information is derived from the…
Improved multidimensional semiclassical tunneling theory.
Wagner, Albert F
2013-12-12
We show that the analytic multidimensional semiclassical tunneling formula of Miller et al. [Miller, W. H.; Hernandez, R.; Handy, N. C.; Jayatilaka, D.; Willets, A. Chem. Phys. Lett. 1990, 172, 62] is qualitatively incorrect for deep tunneling at energies well below the top of the barrier. The origin of this deficiency is that the formula uses an effective barrier weakly related to the true energetics but correctly adjusted to reproduce the harmonic description and anharmonic corrections of the reaction path at the saddle point as determined by second order vibrational perturbation theory. We present an analytic improved semiclassical formula that correctly includes energetic information and allows a qualitatively correct representation of deep tunneling. This is done by constructing a three segment composite Eckart potential that is continuous everywhere in both value and derivative. This composite potential has an analytic barrier penetration integral from which the semiclassical action can be derived and then used to define the semiclassical tunneling probability. The middle segment of the composite potential by itself is superior to the original formula of Miller et al. because it incorporates the asymmetry of the reaction barrier produced by the known reaction exoergicity. Comparison of the semiclassical and exact quantum tunneling probability for the pure Eckart potential suggests a simple threshold multiplicative factor to the improved formula to account for quantum effects very near threshold not represented by semiclassical theory. The deep tunneling limitations of the original formula are echoed in semiclassical high-energy descriptions of bound vibrational states perpendicular to the reaction path at the saddle point. However, typically ab initio energetic information is not available to correct it. The Supporting Information contains a Fortran code, test input, and test output that implements the improved semiclassical tunneling formula. PMID:24224758
Image demodulation using multidimensional energy separation
NASA Astrophysics Data System (ADS)
Maragos, Petros; Bovik, Alan C.
1995-09-01
Locally narrow-band images can be modeled as two-dimensional (2D) spatial AM-FM signals with several applications in image texture analysis and computer vision. We formulate an image-demodulation problem and present a solution based on the multidimensional energy operator Phi (f)= \\double-vertical-bar \\inverted-Delta-triangle f \\double-vertical-bar 2-f \\inverted-Delta-triangle 2 f . This nonlinear operator is a multidimensional extension of the one-dimensional (1D) energy-tracking operator Psi (f)=( f\\prime)2 -ff\\prime\\prime , which has been found useful for demodulating 1D AM-FM and speech signals. We discuss some interesting properties of the multidimensional operator and develop a multidimensional energy-separation algorithm to estimate the amplitude envelope and instantaneous frequencies of 2D spatially varying AM-FM signals. Experiments are also presented on applying this 2D energy-demodulation algorithm to estimate the instantaneous amplitude contrast and spatial frequencies of image textures bandpass filtered by means of Gabor filters. The attractive features of the multidimensional energy operator and the 2D energy-separation algorithm are their simplicity, efficiency, and ability to track instantaneously varying
Fast adaptive estimation of multidimensional psychometric functions.
DiMattina, Christopher
2015-01-01
Recently in vision science there has been great interest in understanding the perceptual representations of complex multidimensional stimuli. Therefore, it is becoming very important to develop methods for performing psychophysical experiments with multidimensional stimuli and efficiently estimating psychometric models that have multiple free parameters. In this methodological study, I analyze three efficient implementations of the popular Ψ method for adaptive data collection, two of which are novel approaches to psychophysical experiments. Although the standard implementation of the Ψ procedure is intractable in higher dimensions, I demonstrate that my implementations generalize well to complex psychometric models defined in multidimensional stimulus spaces and can be implemented very efficiently on standard laboratory computers. I show that my implementations may be of particular use for experiments studying how subjects combine multiple cues to estimate sensory quantities. I discuss strategies for speeding up experiments and suggest directions for future research in this rapidly growing area at the intersection of cognitive science, neuroscience, and machine learning.
Fast adaptive estimation of multidimensional psychometric functions.
DiMattina, Christopher
2015-01-01
Recently in vision science there has been great interest in understanding the perceptual representations of complex multidimensional stimuli. Therefore, it is becoming very important to develop methods for performing psychophysical experiments with multidimensional stimuli and efficiently estimating psychometric models that have multiple free parameters. In this methodological study, I analyze three efficient implementations of the popular Ψ method for adaptive data collection, two of which are novel approaches to psychophysical experiments. Although the standard implementation of the Ψ procedure is intractable in higher dimensions, I demonstrate that my implementations generalize well to complex psychometric models defined in multidimensional stimulus spaces and can be implemented very efficiently on standard laboratory computers. I show that my implementations may be of particular use for experiments studying how subjects combine multiple cues to estimate sensory quantities. I discuss strategies for speeding up experiments and suggest directions for future research in this rapidly growing area at the intersection of cognitive science, neuroscience, and machine learning. PMID:26200886
... Homework? Here's Help White House Lunch Recipes What's Motion Sickness? KidsHealth > For Kids > What's Motion Sickness? Print ... motion sickness might get even worse. continue Avoiding Motion Sickness To avoid motion sickness: Put your best ...
ERIC Educational Resources Information Center
Lavenda, Bernard H.
1985-01-01
Explains the phenomenon of Brownian motion, which serves as a mathematical model for random processes. Topics addressed include kinetic theory, Einstein's theory, particle displacement, and others. Points out that observations of the random course of a particle suspended in fluid led to the first accurate measurement of atomic mass. (DH)
Confirmatory Factor Analysis and Profile Analysis via Multidimensional Scaling
ERIC Educational Resources Information Center
Kim, Se-Kang; Davison, Mark L.; Frisby, Craig L.
2007-01-01
This paper describes the Confirmatory Factor Analysis (CFA) parameterization of the Profile Analysis via Multidimensional Scaling (PAMS) model to demonstrate validation of profile pattern hypotheses derived from multidimensional scaling (MDS). Profile Analysis via Multidimensional Scaling (PAMS) is an exploratory method for identifying major…
The Efficacy of Multidimensional Constraint Keys in Database Query Performance
ERIC Educational Resources Information Center
Cardwell, Leslie K.
2012-01-01
This work is intended to introduce a database design method to resolve the two-dimensional complexities inherent in the relational data model and its resulting performance challenges through abstract multidimensional constructs. A multidimensional constraint is derived and utilized to implement an indexed Multidimensional Key (MK) to abstract a…
Ultrafast multidimensional Laplace NMR for a rapid and sensitive chemical analysis.
Ahola, Susanna; Zhivonitko, Vladimir V; Mankinen, Otto; Zhang, Guannan; Kantola, Anu M; Chen, Hsueh-Ying; Hilty, Christian; Koptyug, Igor V; Telkki, Ville-Veikko
2015-09-18
Traditional nuclear magnetic resonance (NMR) spectroscopy relies on the versatile chemical information conveyed by spectra. To complement conventional NMR, Laplace NMR explores diffusion and relaxation phenomena to reveal details on molecular motions. Under a broad concept of ultrafast multidimensional Laplace NMR, here we introduce an ultrafast diffusion-relaxation correlation experiment enhancing the resolution and information content of corresponding 1D experiments as well as reducing the experiment time by one to two orders of magnitude or more as compared with its conventional 2D counterpart. We demonstrate that the method allows one to distinguish identical molecules in different physical environments and provides chemical resolution missing in NMR spectra. Although the sensitivity of the new method is reduced due to spatial encoding, the single-scan approach enables one to use hyperpolarized substances to boost the sensitivity by several orders of magnitude, significantly enhancing the overall sensitivity of multidimensional Laplace NMR.
Ultrafast multidimensional Laplace NMR for a rapid and sensitive chemical analysis
Ahola, Susanna; Zhivonitko, Vladimir V; Mankinen, Otto; Zhang, Guannan; Kantola, Anu M.; Chen, Hsueh-Ying; Hilty, Christian; Koptyug, Igor V.; Telkki, Ville-Veikko
2015-01-01
Traditional nuclear magnetic resonance (NMR) spectroscopy relies on the versatile chemical information conveyed by spectra. To complement conventional NMR, Laplace NMR explores diffusion and relaxation phenomena to reveal details on molecular motions. Under a broad concept of ultrafast multidimensional Laplace NMR, here we introduce an ultrafast diffusion-relaxation correlation experiment enhancing the resolution and information content of corresponding 1D experiments as well as reducing the experiment time by one to two orders of magnitude or more as compared with its conventional 2D counterpart. We demonstrate that the method allows one to distinguish identical molecules in different physical environments and provides chemical resolution missing in NMR spectra. Although the sensitivity of the new method is reduced due to spatial encoding, the single-scan approach enables one to use hyperpolarized substances to boost the sensitivity by several orders of magnitude, significantly enhancing the overall sensitivity of multidimensional Laplace NMR. PMID:26381101
Ultrafast multidimensional Laplace NMR for a rapid and sensitive chemical analysis
NASA Astrophysics Data System (ADS)
Ahola, Susanna; Zhivonitko, Vladimir V.; Mankinen, Otto; Zhang, Guannan; Kantola, Anu M.; Chen, Hsueh-Ying; Hilty, Christian; Koptyug, Igor V.; Telkki, Ville-Veikko
2015-09-01
Traditional nuclear magnetic resonance (NMR) spectroscopy relies on the versatile chemical information conveyed by spectra. To complement conventional NMR, Laplace NMR explores diffusion and relaxation phenomena to reveal details on molecular motions. Under a broad concept of ultrafast multidimensional Laplace NMR, here we introduce an ultrafast diffusion-relaxation correlation experiment enhancing the resolution and information content of corresponding 1D experiments as well as reducing the experiment time by one to two orders of magnitude or more as compared with its conventional 2D counterpart. We demonstrate that the method allows one to distinguish identical molecules in different physical environments and provides chemical resolution missing in NMR spectra. Although the sensitivity of the new method is reduced due to spatial encoding, the single-scan approach enables one to use hyperpolarized substances to boost the sensitivity by several orders of magnitude, significantly enhancing the overall sensitivity of multidimensional Laplace NMR.
Multidimensional Human Dynamics in Mobile Phone Communications
Quadri, Christian; Zignani, Matteo; Capra, Lorenzo; Gaito, Sabrina; Rossi, Gian Paolo
2014-01-01
In today's technology-assisted society, social interactions may be expressed through a variety of techno-communication channels, including online social networks, email and mobile phones (calls, text messages). Consequently, a clear grasp of human behavior through the diverse communication media is considered a key factor in understanding the formation of the today's information society. So far, all previous research on user communication behavior has focused on a sole communication activity. In this paper we move forward another step on this research path by performing a multidimensional study of human sociality as an expression of the use of mobile phones. The paper focuses on user temporal communication behavior in the interplay between the two complementary communication media, text messages and phone calls, that represent the bi-dimensional scenario of analysis. Our study provides a theoretical framework for analyzing multidimensional bursts as the most general burst category, that includes one-dimensional bursts as the simplest case, and offers empirical evidence of their nature by following the combined phone call/text message communication patterns of approximately one million people over three-month period. This quantitative approach enables the design of a generative model rooted in the three most significant features of the multidimensional burst - the number of dimensions, prevalence and interleaving degree - able to reproduce the main media usage attitude. The other findings of the paper include a novel multidimensional burst detection algorithm and an insight analysis of the human media selection process. PMID:25068479
Longitudinal Network Analysis Using Multidimensional Scaling.
ERIC Educational Resources Information Center
Barnett, George A.; Palmer, Mark T.
The Galileo System, a variant of metric multidimensional scaling, is used in this paper to analyze over-time changes in social networks. The paper first discusses the theoretical necessity for the use of this procedure and the methodological problems associated with its use. It then examines the air traffic network among 31 major cities in the…
Multidimensional Perspectives on Principal Leadership Effectiveness
ERIC Educational Resources Information Center
Beycioglu, Kadir, Ed.; Pashiardis, Petros, Ed.
2015-01-01
Exceptional management skills are crucial to success in educational environments. As school leaders, principals are expected to effectively supervise the school system while facing a multitude of issues and demands. "Multidimensional Perspectives on Principal Leadership Effectiveness" combines best practices and the latest approaches in…
Uncertainty of Comparative Judgments and Multidimensional Structure
ERIC Educational Resources Information Center
Sjoberg, Lennart
1975-01-01
An analysis of preferences with respect to silhouette drawings of nude females is presented. Systematic intransitivities were discovered. The dispersions of differences (comparatal dispersons) were shown to reflect the multidimensional structure of the stimuli, a finding expected on the basis of prior work. (Author)
Bilingual Creativity, Multidimensional Analysis, and World Englishes.
ERIC Educational Resources Information Center
Baker, Wendy; Eggington, William G.
1999-01-01
Using Biber's multidimensional analysis (1998) to examine a large corpus of world English literatures written in Indian, West African, British, Anglo-American, and Mexican-American varieties of English, examines whether quantitative analyses can also be insightful and useful in the examination of world Englishes literatures in expanding…
Multidimensional human dynamics in mobile phone communications.
Quadri, Christian; Zignani, Matteo; Capra, Lorenzo; Gaito, Sabrina; Rossi, Gian Paolo
2014-01-01
In today's technology-assisted society, social interactions may be expressed through a variety of techno-communication channels, including online social networks, email and mobile phones (calls, text messages). Consequently, a clear grasp of human behavior through the diverse communication media is considered a key factor in understanding the formation of the today's information society. So far, all previous research on user communication behavior has focused on a sole communication activity. In this paper we move forward another step on this research path by performing a multidimensional study of human sociality as an expression of the use of mobile phones. The paper focuses on user temporal communication behavior in the interplay between the two complementary communication media, text messages and phone calls, that represent the bi-dimensional scenario of analysis. Our study provides a theoretical framework for analyzing multidimensional bursts as the most general burst category, that includes one-dimensional bursts as the simplest case, and offers empirical evidence of their nature by following the combined phone call/text message communication patterns of approximately one million people over three-month period. This quantitative approach enables the design of a generative model rooted in the three most significant features of the multidimensional burst - the number of dimensions, prevalence and interleaving degree - able to reproduce the main media usage attitude. The other findings of the paper include a novel multidimensional burst detection algorithm and an insight analysis of the human media selection process. PMID:25068479
Multidimensional human dynamics in mobile phone communications.
Quadri, Christian; Zignani, Matteo; Capra, Lorenzo; Gaito, Sabrina; Rossi, Gian Paolo
2014-01-01
In today's technology-assisted society, social interactions may be expressed through a variety of techno-communication channels, including online social networks, email and mobile phones (calls, text messages). Consequently, a clear grasp of human behavior through the diverse communication media is considered a key factor in understanding the formation of the today's information society. So far, all previous research on user communication behavior has focused on a sole communication activity. In this paper we move forward another step on this research path by performing a multidimensional study of human sociality as an expression of the use of mobile phones. The paper focuses on user temporal communication behavior in the interplay between the two complementary communication media, text messages and phone calls, that represent the bi-dimensional scenario of analysis. Our study provides a theoretical framework for analyzing multidimensional bursts as the most general burst category, that includes one-dimensional bursts as the simplest case, and offers empirical evidence of their nature by following the combined phone call/text message communication patterns of approximately one million people over three-month period. This quantitative approach enables the design of a generative model rooted in the three most significant features of the multidimensional burst - the number of dimensions, prevalence and interleaving degree - able to reproduce the main media usage attitude. The other findings of the paper include a novel multidimensional burst detection algorithm and an insight analysis of the human media selection process.
Multidimensional IRT Models for Composite Scores
ERIC Educational Resources Information Center
Yen, Shu Jing; Walker, Leah
2007-01-01
Tests of English Language Proficiency are often designed such that each section of the test measures a single latent ability. For instance an English Proficiency Assessment might consist of sections measuring Speaking, Listening, and Reading ability. However, Overall English Proficiency and composite abilities are naturally multidimensional. This…
Determining Factor Structure in a Multidimensional Inventory.
ERIC Educational Resources Information Center
Deeter, Thomas E.; Gill, Diane L.
A two-step procedure is described and used to revise a multidimensional inventory in its developmental stages. First, the latent factors influencing the observed variables on the inventory are determined and justified using the following five methods: Kaiser's criterion, root staring, examination of difference values, examination of root mean…
Stability of Adolescents' Multidimensional Life Satisfaction Reports
ERIC Educational Resources Information Center
Antaramian, Susan P.; Huebner, E. Scott
2009-01-01
Eighty-four students were administered the Multidimensional Students' Life Satisfaction Scale (MSLSS) on three occasions, 1 year apart (Grades 8, 9, and 10). The 1-year stability coefficients ranged from 0.29 to 0.59, whereas the 2-year stability coefficients ranged from 0.41 to 0.59. MSLSS mean scores were consistent across administrations, with…
A New Heterogeneous Multidimensional Unfolding Procedure
ERIC Educational Resources Information Center
Park, Joonwook; Rajagopal, Priyali; DeSarbo, Wayne S.
2012-01-01
A variety of joint space multidimensional scaling (MDS) methods have been utilized for the spatial analysis of two- or three-way dominance data involving subjects' preferences, choices, considerations, intentions, etc. so as to provide a parsimonious spatial depiction of the underlying relevant dimensions, attributes, stimuli, and/or subjects'…
Multidimensional NMR spectroscopy in a single scan.
Gal, Maayan; Frydman, Lucio
2015-11-01
Multidimensional NMR has become one of the most widespread spectroscopic tools available to study diverse structural and functional aspects of organic and biomolecules. A main feature of multidimensional NMR is the relatively long acquisition times that these experiments demand. For decades, scientists have been working on a variety of alternatives that would enable NMR to overcome this limitation, and deliver its data in shorter acquisition times. Counting among these methodologies is the so-called ultrafast (UF) NMR approach, which in principle allows one to collect arbitrary multidimensional correlations in a single sub-second transient. By contrast to conventional acquisitions, a main feature of UF NMR is a spatiotemporal manipulation of the spins that imprints the chemical shift and/or J-coupling evolutions being sought, into a spatial pattern. Subsequent gradient-based manipulations enable the reading out of this information and its multidimensional correlation into patterns that are identical to those afforded by conventional techniques. The current review focuses on the fundamental principles of this spatiotemporal UF NMR manipulation, and on a few of the methodological extensions that this form of spectroscopy has undergone during the years. PMID:26249041
A Multidimensional Construct of Self-Esteem
ERIC Educational Resources Information Center
Norem-Hebeisen, Ardyth A.
1976-01-01
Evidence for construct validity of this multi-dimensional concept of self esteem includes the relative congruence of the factor structure with the theoretical construct, the stability of the structure when subjected to a series of empirical tests, increasingly positive self-referent responses with increasing age, willingness to become more…
The Multidimensional Curriculum Model (MdCM)
ERIC Educational Resources Information Center
Vidergor, Hava E.
2010-01-01
The multidimensional Curriculum Model (MdCM) helps teachers to better prepare gifted and able students for our changing world, acquiring much needed skills. It is influenced by general learning theory of constructivism, notions of preparing students for 21st century, Teaching the Future Model, and current comprehensive curriculum models for…
Scaling Multidimensional Inference for Structured Gaussian Processes.
Gilboa, Elad; Saatçi, Yunus; Cunningham, John P
2013-09-30
Exact Gaussian process (GP) regression has O(N^3) runtime for data size N, making it intractable for large N. Many algorithms for improving GP scaling approximate the covariance with lower rank matrices. Other work has exploited structure inherent in particular covariance functions, including GPs with implied Markov structure, and inputs on a lattice (both enable O(N) or O(N log N) runtime). However, these GP advances have not been well extended to the multidimensional input setting, despite the preponderance of multidimensional applications. This paper introduces and tests three novel extensions of structured GPs to multidimensional inputs, for models with additive and multiplicative kernels. First we present a new method for inference in additive GPs, showing a novel connection between the classic backfitting method and the Bayesian framework. We extend this model using two advances: a variant of projection pursuit regression, and a Laplace approximation for non-Gaussian observations. Lastly, for multiplicative kernel structure, we present a novel method for GPs with inputs on a multidimensional grid. We illustrate the power of these three advances on several datasets, achieving performance equal to or very close to the naive GP at orders of magnitude less cost.
Scaling Multidimensional Inference for Structured Gaussian Processes.
Gilboa, Elad; Saatçi, Yunus; Cunningham, John P
2015-02-01
Exact Gaussian process (GP) regression has O(N(3)) runtime for data size N, making it intractable for large N . Many algorithms for improving GP scaling approximate the covariance with lower rank matrices. Other work has exploited structure inherent in particular covariance functions, including GPs with implied Markov structure, and inputs on a lattice (both enable O(N) or O(N log N) runtime). However, these GP advances have not been well extended to the multidimensional input setting, despite the preponderance of multidimensional applications. This paper introduces and tests three novel extensions of structured GPs to multidimensional inputs, for models with additive and multiplicative kernels. First we present a new method for inference in additive GPs, showing a novel connection between the classic backfitting method and the Bayesian framework. We extend this model using two advances: a variant of projection pursuit regression, and a Laplace approximation for non-Gaussian observations. Lastly, for multiplicative kernel structure, we present a novel method for GPs with inputs on a multidimensional grid. We illustrate the power of these three advances on several data sets, achieving performance equal to or very close to the naive GP at orders of magnitude less cost.
Multidimensional neural growing networks and computer intelligence
Yashchenko, V.A.
1995-03-01
This paper examines information-computation processes in time and in space and some aspects of computer intelligence using multidimensional matrix neural growing networks. In particular, issues of object-oriented {open_quotes}thinking{close_quotes} of computers are considered.
Multidimensional Treatment of Fear of Death.
ERIC Educational Resources Information Center
Hoelter, Jon W.
1979-01-01
Presents a multidimensional conception of fear of death and provides subscales for measuring suggested dimensions (fear of the dying process, of the dead, of being destroyed, for significant others, of the unknown, of conscious death, for body after death, and of premature death). Evidence for construct validity is provided. (Author/BEF)
Paradoxical Results in Multidimensional Item Response Theory
ERIC Educational Resources Information Center
Hooker, Giles; Finkelman, Matthew; Schwartzman, Armin
2009-01-01
In multidimensional item response theory (MIRT), it is possible for the estimate of a subject's ability in some dimension to decrease after they have answered a question correctly. This paper investigates how and when this type of paradoxical result can occur. We demonstrate that many response models and statistical estimates can produce…
Unidimensional Interpretations for Multidimensional Test Items
ERIC Educational Resources Information Center
Kahraman, Nilufer
2013-01-01
This article considers potential problems that can arise in estimating a unidimensional item response theory (IRT) model when some test items are multidimensional (i.e., show a complex factorial structure). More specifically, this study examines (1) the consequences of model misfit on IRT item parameter estimates due to unintended minor item-level…
Taillemite, J P; Devaulx, P; Bousquet, F
1997-01-01
Motion sickness is a general term covering sea-sickness, car-sickness, air-sickness, and space-sickness. Symptoms can occur when a person is exposed to unfamiliar movement whether real or simulated. Despite progress in the technology and comfort of modern transportation (planes, boats, and overland vehicles), a great number of travelers still experience motion sickness. Bouts are characterized by an initial phase of mild discomfort followed by neurologic and gastro-intestinal manifestations. The delay in onset depends on specific circumstances and individual susceptibility. Attacks are precipitated by conflicting sensory, visual, and vestibular signals but the underlying mechanism is unclear. Most medications used for prevention and treatment (e.g. anticholinergics and antihistamines) induce unwanted sedation. Furthermore no one drug is completely effective or preventive under all conditions.
On the monotonicity of multidimensional finite difference schemes
NASA Astrophysics Data System (ADS)
Kovyrkina, O.; Ostapenko, V.
2016-10-01
The classical concept of monotonicity, introduced by Godunov for linear one-dimensional difference schemes, is extended to multidimensional case. Necessary and sufficient conditions of monotonicity are obtained for linear multidimensional difference schemes of first order. The constraints on the numerical viscosity are given that ensure the monotonicity of a difference scheme in the multidimensional case. It is proposed a modification of the second order multidimensional CABARET scheme that preserves the monotonicity of one-dimensional discrete solutions and, as a result, ensures higher smoothness in the computation of multidimensional discontinuous solutions. The results of two-dimensional test computations illustrating the advantages of the modified CABARET scheme are presented.
Multidimensional x-space magnetic particle imaging.
Goodwill, Patrick W; Conolly, Steven M
2011-09-01
Magnetic particle imaging (MPI) is a promising new medical imaging tracer modality with potential applications in human angiography, cancer imaging, in vivo cell tracking, and inflammation imaging. Here we demonstrate both theoretically and experimentally that multidimensional MPI is a linear shift-invariant imaging system with an analytic point spread function. We also introduce a fast image reconstruction method that obtains the intrinsic MPI image with high signal-to-noise ratio via a simple gridding operation in x-space. We also demonstrate a method to reconstruct large field-of-view (FOV) images using partial FOV scanning, despite the loss of first harmonic image information due to direct feedthrough contamination. We conclude with the first experimental test of multidimensional x-space MPI.
On the Need for Multidimensional Stirling Analysis
NASA Technical Reports Server (NTRS)
Dyson, Rodger; Wilson, Scott; Tew, Roy; Demko, Rikako
2006-01-01
Contents include the following: Dual opposed convertors. High efficiency. Low mass space power. One-dimensional analysis. Fast computation. Design optimizations are easily done. Need for multidimensional modeling. Axisymmetric simulation. Flow characteristics. Low mach number. Laminar, transitional, and turbulent flow. Conjugate heat transfer. Third order analysis. Recent whole engine modeling. Regenerator geometry. Turbulence modeling. Flat head heater not 1-D. Empirical coefficients needed. Experiment design. Flow distribution. Sensor placement. Calibration. Validation.
Multidimensional integration in a heterogeneous network environment
NASA Astrophysics Data System (ADS)
Veseli, Siniša
1998-01-01
We consider several issues related to the multidimensional integration using a network of heterogeneous computers. Based on these considerations, we develop a new general purpose scheme which can significantly reduce the time needed for evaluation of integrals with CPU intensive integrands. This scheme is a parallel version of the well-known adaptive Monte Carlo method (the VEGAS algorithm), and is incorporated into a new integration package which uses the standard set of message-passing routines in the PVM software system.
Multidimensional reaction rate theory with anisotropic diffusion.
Berezhkovskii, Alexander M; Szabo, Attila; Greives, Nicholas; Zhou, Huan-Xiang
2014-11-28
An analytical expression is derived for the rate constant that describes diffusive transitions between two deep wells of a multidimensional potential. The expression, in contrast to the Kramers-Langer formula for the rate constant, is valid even when the diffusion is highly anisotropic. Our approach is based on a variational principle for the reactive flux and uses a trial function for the splitting probability or commitor. The theoretical result is validated by Brownian dynamics simulations.
Multidimensional Homophily in Friendship Networks1
Block, Per; Grund, Thomas
2014-01-01
Homophily – the tendency for individuals to associate with similar others – is one of the most persistent findings in social network analysis. Its importance is established along the lines of a multitude of sociologically relevant dimensions, e.g. sex, ethnicity and social class. Existing research, however, mostly focuses on one dimension at a time. But people are inherently multidimensional, have many attributes and are members of multiple groups. In this article, we explore such multidimensionality further in the context of network dynamics. Are friendship ties increasingly likely to emerge and persist when individuals have an increasing number of attributes in common? We analyze eleven friendship networks of adolescents, draw on stochastic actor-oriented network models and focus on the interaction of established homophily effects. Our results indicate that main effects for homophily on various dimensions are positive. At the same time, the interaction of these homophily effects is negative. There seems to be a diminishing effect for having more than one attribute in common. We conclude that studies of homophily and friendship formation need to address such multidimensionality further. PMID:25525503
NASA Technical Reports Server (NTRS)
1993-01-01
MOOG, Inc. supplies hydraulic actuators for the Space Shuttle. When MOOG learned NASA was interested in electric actuators for possible future use, the company designed them with assistance from Marshall Space Flight Center. They also decided to pursue the system's commercial potential. This led to partnership with InterActive Simulation, Inc. for production of cabin flight simulators for museums, expositions, etc. The resulting products, the Magic Motion Simulator 30 Series, are the first electric powered simulators. Movements are computer-guided, including free fall to heighten the sense of moving through space. A projection system provides visual effects, and the 11 speakers of a digital laser based sound system add to the realism. The electric actuators are easier to install, have lower operating costs, noise, heat and staff requirements. The U.S. Space & Rocket Center and several other organizations have purchased the simulators.
Auditory motion affects visual biological motion processing.
Brooks, A; van der Zwan, R; Billard, A; Petreska, B; Clarke, S; Blanke, O
2007-02-01
The processing of biological motion is a critical, everyday task performed with remarkable efficiency by human sensory systems. Interest in this ability has focused to a large extent on biological motion processing in the visual modality (see, for example, Cutting, J. E., Moore, C., & Morrison, R. (1988). Masking the motions of human gait. Perception and Psychophysics, 44(4), 339-347). In naturalistic settings, however, it is often the case that biological motion is defined by input to more than one sensory modality. For this reason, here in a series of experiments we investigate behavioural correlates of multisensory, in particular audiovisual, integration in the processing of biological motion cues. More specifically, using a new psychophysical paradigm we investigate the effect of suprathreshold auditory motion on perceptions of visually defined biological motion. Unlike data from previous studies investigating audiovisual integration in linear motion processing [Meyer, G. F. & Wuerger, S. M. (2001). Cross-modal integration of auditory and visual motion signals. Neuroreport, 12(11), 2557-2560; Wuerger, S. M., Hofbauer, M., & Meyer, G. F. (2003). The integration of auditory and motion signals at threshold. Perception and Psychophysics, 65(8), 1188-1196; Alais, D. & Burr, D. (2004). No direction-specific bimodal facilitation for audiovisual motion detection. Cognitive Brain Research, 19, 185-194], we report the existence of direction-selective effects: relative to control (stationary) auditory conditions, auditory motion in the same direction as the visually defined biological motion target increased its detectability, whereas auditory motion in the opposite direction had the inverse effect. Our data suggest these effects do not arise through general shifts in visuo-spatial attention, but instead are a consequence of motion-sensitive, direction-tuned integration mechanisms that are, if not unique to biological visual motion, at least not common to all types of
Nuclear Forensic Inferences Using Iterative Multidimensional Statistics
Robel, M; Kristo, M J; Heller, M A
2009-06-09
Nuclear forensics involves the analysis of interdicted nuclear material for specific material characteristics (referred to as 'signatures') that imply specific geographical locations, production processes, culprit intentions, etc. Predictive signatures rely on expert knowledge of physics, chemistry, and engineering to develop inferences from these material characteristics. Comparative signatures, on the other hand, rely on comparison of the material characteristics of the interdicted sample (the 'questioned sample' in FBI parlance) with those of a set of known samples. In the ideal case, the set of known samples would be a comprehensive nuclear forensics database, a database which does not currently exist. In fact, our ability to analyze interdicted samples and produce an extensive list of precise materials characteristics far exceeds our ability to interpret the results. Therefore, as we seek to develop the extensive databases necessary for nuclear forensics, we must also develop the methods necessary to produce the necessary inferences from comparison of our analytical results with these large, multidimensional sets of data. In the work reported here, we used a large, multidimensional dataset of results from quality control analyses of uranium ore concentrate (UOC, sometimes called 'yellowcake'). We have found that traditional multidimensional techniques, such as principal components analysis (PCA), are especially useful for understanding such datasets and drawing relevant conclusions. In particular, we have developed an iterative partial least squares-discriminant analysis (PLS-DA) procedure that has proven especially adept at identifying the production location of unknown UOC samples. By removing classes which fell far outside the initial decision boundary, and then rebuilding the PLS-DA model, we have consistently produced better and more definitive attributions than with a single pass classification approach. Performance of the iterative PLS-DA method
Construct continuity in the presence of multidimensionality
NASA Astrophysics Data System (ADS)
Staniewska, Dorota
Unidimensionality -- a condition, under which only one dominant construct is being measured by the test, is a fundamental assumption of most modern day psychometric models. However, some tests are multidimensional by design. A test, for instance, might measure physics, biology and chemistry subscales combined to measure a "general science" composite. The relative magnitudes of those subscales sometimes shift from administration to administration, which results in an altered composite. This study examined the conditions under which two different forms of a multidimensional test measure the same composite construct to a degree that allows them to be equated, i.e. used interchangeably. IRT true-score equating was used in a simulation study to assess the closeness of the scores on the forms. Conditions examined included the correlations between subscales, varying number of items per subscale form to form, and different subpopulation ability estimates on the subscales. Differences in the equating errors due to generating model (1PL or 3PL) were also examined. A way of calculating a unidimensional composite from a two-dimensional ability was devised and compared to the unidimensional composite obtained from Parscale. It was found that in general, the errors increase with decreasing correlation between traits and increased divergence of the two forms to be equated, with the later being the main predictor of the equating errors. However, the magnitude of those errors was small for the population as a whole especially when all examinee abilities are drawn from the same distribution. It was concluded that IRT true score equating is relatively robust to multidimensionality for the conditions examined, especially if the overall population score is desired. However, when accurate estimate of the equated score for individuals at the extremes of the population is needed, or whenever population abilities are drawn from more than one distribution, the unidimensional true score
ERIC Educational Resources Information Center
Toro, Maritsa
2011-01-01
The statistical assessment of dimensionality provides evidence of the underlying constructs measured by a survey or test instrument. This study focuses on educational measurement, specifically tests comprised of items described as multidimensional. That is, items that require examinee proficiency in multiple content areas and/or multiple cognitive…
Palmprint based multidimensional fuzzy vault scheme.
Liu, Hailun; Sun, Dongmei; Xiong, Ke; Qiu, Zhengding
2014-01-01
Fuzzy vault scheme (FVS) is one of the most popular biometric cryptosystems for biometric template protection. However, error correcting code (ECC) proposed in FVS is not appropriate to deal with real-valued biometric intraclass variances. In this paper, we propose a multidimensional fuzzy vault scheme (MDFVS) in which a general subspace error-tolerant mechanism is designed and embedded into FVS to handle intraclass variances. Palmprint is one of the most important biometrics; to protect palmprint templates; a palmprint based MDFVS implementation is also presented. Experimental results show that the proposed scheme not only can deal with intraclass variances effectively but also could maintain the accuracy and meanwhile enhance security. PMID:24892094
A multidimensional representation model of geographic features
Usery, E. Lynn; Timson, George; Coletti, Mark
2016-01-28
A multidimensional model of geographic features has been developed and implemented with data from The National Map of the U.S. Geological Survey. The model, programmed in C++ and implemented as a feature library, was tested with data from the National Hydrography Dataset demonstrating the capability to handle changes in feature attributes, such as increases in chlorine concentration in a stream, and feature geometry, such as the changing shoreline of barrier islands over time. Data can be entered directly, from a comma separated file, or features with attributes and relationships can be automatically populated in the model from data in the Spatial Data Transfer Standard format.
A multidimensional representation model of geographic features
Usery, E. Lynn; Timson, George; Coletti, Mark
2016-01-01
A multidimensional model of geographic features has been developed and implemented with data from The National Map of the U.S. Geological Survey. The model, programmed in C++ and implemented as a feature library, was tested with data from the National Hydrography Dataset demonstrating the capability to handle changes in feature attributes, such as increases in chlorine concentration in a stream, and feature geometry, such as the changing shoreline of barrier islands over time. Data can be entered directly, from a comma separated file, or features with attributes and relationships can be automatically populated in the model from data in the Spatial Data Transfer Standard format.
Multidimensional world, inflation, and modern acceleration
Bronnikov, K. A.; Rubin, S. G.; Svadkovsky, I. V.
2010-04-15
Starting from pure multidimensional gravity with curvature-nonlinear terms but no matter fields in the initial action, we obtain a cosmological model with two effective scalar fields related to the size of two extra factor spaces. The model includes both an early inflationary stage and that of modern accelerated expansion and satisfies the observational data. There are no small parameters; the effective inflaton mass depends on the initial conditions which explain its small value as compared to the Planck mass. At the modern stage, the size of extra dimensions slowly increases, therefore this model predicts drastic changes in the physical laws of our Universe in the remote future.
Multidimensional visualization and browsing for intelligence analysis
Crow, V.; Pottier, M.; Thomas, J.
1994-09-01
Visualization tools have been invaluable in the process of scientific discovery by providing researchers with insights gained through graphical tools and techniques. At PNL, the Multidimensional Visualization and Advanced Browsing (MVAB) project is extending visualization technology to the problems of intelligence analysis of textual documents by creating spatial representations of textual information. By representing an entire corpus of documents as points in a coordinate space of two or more dimensions, the tools developed by the MVAB team give the analyst the ability to quickly browse the entire document base and determine relationships among documents and publication patterns not readily discernible through traditional lexical means.
Evolution of multidimensional flat anisotropic cosmological models
Beloborodov, A. ); Demianski, M. Nicolaus Copernicus Astronomical Center, Bartycka 18, 00-716 Warsaw International Center for Relativistic Astrophysics , Universita di Roma I, La Sapienza, Rome ); Ivanov, P.; Polnarev, A.G. )
1993-07-15
We study the dynamics of a flat multidimensional anisotropic cosmological model filled with an anisotropic fluidlike medium. By an appropriate choice of variables, the dynamical equations reduce to a two-dimensional dynamical system. We present a detailed analysis of the time evolution of this system and the conditions of the existence of spacetime singularities. We investigate the conditions under which violent, exponential, and power-law inflation is possible. We show that dimensional reduction cannot proceed by anti-inflation (rapid contraction of internal space). Our model indicates that it is very difficult to achieve dimensional reduction by classical means.
Analysis of cardiac interventricular septum motion in different respiratory states
NASA Astrophysics Data System (ADS)
Tautz, Lennart; Feng, Li; Otazo, Ricardo; Hennemuth, Anja; Axel, Leon
2016-03-01
The interaction between the left and right heart ventricles (LV and RV) depends on load and pressure conditions that are affected by cardiac contraction and respiration cycles. A novel MRI sequence, XD-GRASP, allows the acquisition of multi-dimensional, respiration-sorted and cardiac-synchronized free-breathing image data. In these data, effects of the cardiac and respiratory cycles on the LV/RV interaction can be observed independently. To enable the analysis of such data, we developed a semi-automatic exploration workflow. After tracking a cross-sectional line positioned over the heart, over all motion states, the septum and heart wall border locations are detected by analyzing the grey-value profile under the lines. These data are used to quantify septum motion, both in absolute units and as a fraction of the heart size, to compare values for different subjects. In addition to conventional visualization techniques, we used color maps for intuitive exploration of the variable values for this multi-dimensional data set. We acquired short-axis image data of nine healthy volunteers, to analyze the position and the motion of the interventricular septum in different breathing states and different cardiac cycle phases. The results indicate a consistent range of normal septum motion values, and also suggest that respiratory phase-dependent septum motion is greatest near end-diastolic phases. These new methods are a promising tool to assess LV/RV ventricle interaction and the effects of respiration on this interaction.
Self Motion Perception and Motion Sickness
NASA Technical Reports Server (NTRS)
Fox, Robert A. (Principal Investigator)
1991-01-01
The studies conducted in this research project examined several aspects of motion sickness in animal models. A principle objective of these studies was to investigate the neuroanatomy that is important in motion sickness with the objectives of examining both the utility of putative models and defining neural mechanisms that are important in motion sickness.
Ion motion in self-modulated plasma wakefield accelerators.
Vieira, J; Fonseca, R A; Mori, W B; Silva, L O
2012-10-01
The effects of plasma ion motion in self-modulated plasma-based accelerators are examined. An analytical model describing ion motion in the narrow beam limit is developed and confirmed through multidimensional particle-in-cell simulations. It is shown that the ion motion can lead to the early saturation of the self-modulation instability and to the suppression of the accelerating gradients. This can reduce the total energy that can be transformed into kinetic energy of accelerated particles. For the parameters of future proton-driven plasma accelerator experiments, the ion dynamics can have a strong impact. Possible methods to mitigate the effects of the ion motion in future experiments are demonstrated.
Noncommutative accelerated multidimensional universe dominated by quintessence
NASA Astrophysics Data System (ADS)
El-Nabulsi, Ahmad Rami
2010-04-01
Noncommutative Geometry recently attracted growing interest of cosmologists, mainly after the greatest success of unifying the forces of nature into a single gravitational spectral action in a purely algebraic way, rather than as being an entirely new formalism. In the present work, we discuss a multidimensional Friedmann-Robertson-Walker flat universe in which the perfect fluid has a Gaussian profile in time and depends on a fundamental minimal length sqrt{θ} like ρ= ρ(0)exp (- t 2/4 θ) for some positive constant ρ(0). This special form is motivated by a more recent noncommutative inflationary cosmological model, which was found to be able to drive the universe through a bounce without the need of any scalar field. Furthermore, we conjecture that the generalized equation of state has the special form p= ω a m ρ- ρ,( ω, m)∈ℝ where a( t) is the scale factor. It was found that the expansion of the multidimensional universe accelerates in time and is dominated for very large time by quintessence. Many additional consequences are revealed and discussed in some detail.
Multidimensional Learner Model In Intelligent Learning System
NASA Astrophysics Data System (ADS)
Deliyska, B.; Rozeva, A.
2009-11-01
The learner model in an intelligent learning system (ILS) has to ensure the personalization (individualization) and the adaptability of e-learning in an online learner-centered environment. ILS is a distributed e-learning system whose modules can be independent and located in different nodes (servers) on the Web. This kind of e-learning is achieved through the resources of the Semantic Web and is designed and developed around a course, group of courses or specialty. An essential part of ILS is learner model database which contains structured data about learner profile and temporal status in the learning process of one or more courses. In the paper a learner model position in ILS is considered and a relational database is designed from learner's domain ontology. Multidimensional modeling agent for the source database is designed and resultant learner data cube is presented. Agent's modules are proposed with corresponding algorithms and procedures. Multidimensional (OLAP) analysis guidelines on the resultant learner module for designing dynamic learning strategy have been highlighted.
Multidimensional Modeling of Coronal Rain Dynamics
NASA Astrophysics Data System (ADS)
Fang, X.; Xia, C.; Keppens, R.
2013-07-01
We present the first multidimensional, magnetohydrodynamic simulations that capture the initial formation and long-term sustainment of the enigmatic coronal rain phenomenon. We demonstrate how thermal instability can induce a spectacular display of in situ forming blob-like condensations which then start their intimate ballet on top of initially linear force-free arcades. Our magnetic arcades host a chromospheric, transition region, and coronal plasma. Following coronal rain dynamics for over 80 minutes of physical time, we collect enough statistics to quantify blob widths, lengths, velocity distributions, and other characteristics which directly match modern observational knowledge. Our virtual coronal rain displays the deformation of blobs into V-shaped features, interactions of blobs due to mostly pressure-mediated levitations, and gives the first views of blobs that evaporate in situ or are siphoned over the apex of the background arcade. Our simulations pave the way for systematic surveys of coronal rain showers in true multidimensional settings to connect parameterized heating prescriptions with rain statistics, ultimately allowing us to quantify the coronal heating input.
Heterogeneous multidimensional scaling for complex networks
NASA Astrophysics Data System (ADS)
Xuan, Qi; Ma, Xiaodi; Fu, Chenbo; Dong, Hui; Zhang, Guijun; Yu, Li
2015-07-01
Many real-world networks are essentially heterogeneous, where the nodes have different abilities to gain connections. Such networks are difficult to be embedded into low-dimensional Euclidean space if we ignore the heterogeneity and treat all the nodes equally. In this paper, based on a newly defined heterogeneous distance and a generalized network distance under the constraints of network and triangle inequalities, respectively, we propose a new heterogeneous multidimensional scaling method (HMDS) to embed different networks into proper Euclidean spaces. We find that HMDS behaves much better than the traditional multidimensional scaling method (MDS) in embedding different artificial and real-world networks into Euclidean spaces. Besides, we also propose a method to estimate the appropriate dimensions of Euclidean spaces for different networks, and find that the estimated dimensions are quite close to the real dimensions for those geometrical networks under study. These methods thus can help to better understand the evolution of real-world networks, and have practical importance in network visualization, community detection, link prediction and localization of wireless sensors.
Visualizing multidimensional query results using animation
NASA Astrophysics Data System (ADS)
Sawant, Amit P.; Healey, Christopher G.
2008-01-01
Effective representation of large, complex collections of information (datasets) presents a difficult challenge. Visualization is a solution that uses a visual interface to support efficient analysis and discovery within the data. Our primary goal in this paper is a technique that allows viewers to compare multiple query results representing user-selected subsets of a multidimensional dataset. We present an algorithm that visualizes multidimensional information along a space-filling spiral. Graphical glyphs that vary their position, color, and texture appearance are used to represent attribute values for the data elements in each query result. Guidelines from human perception allow us to construct glyphs that are specifically designed to support exploration, facilitate the discovery of trends and relationships both within and between data elements, and highlight exceptions. A clustering algorithm applied to a user-chosen ranking attribute bundles together similar data elements. This encapsulation is used to show relationships across different queries via animations that morph between query results. We apply our techniques to the MovieLens recommender system, to demonstrate their applicability in a real-world environment, and then conclude with a simple validation experiment to identify the strengths and limitations of our design, compared to a traditional side-by-side visualization.
MULTIDIMENSIONAL MODELING OF CORONAL RAIN DYNAMICS
Fang, X.; Xia, C.; Keppens, R.
2013-07-10
We present the first multidimensional, magnetohydrodynamic simulations that capture the initial formation and long-term sustainment of the enigmatic coronal rain phenomenon. We demonstrate how thermal instability can induce a spectacular display of in situ forming blob-like condensations which then start their intimate ballet on top of initially linear force-free arcades. Our magnetic arcades host a chromospheric, transition region, and coronal plasma. Following coronal rain dynamics for over 80 minutes of physical time, we collect enough statistics to quantify blob widths, lengths, velocity distributions, and other characteristics which directly match modern observational knowledge. Our virtual coronal rain displays the deformation of blobs into V-shaped features, interactions of blobs due to mostly pressure-mediated levitations, and gives the first views of blobs that evaporate in situ or are siphoned over the apex of the background arcade. Our simulations pave the way for systematic surveys of coronal rain showers in true multidimensional settings to connect parameterized heating prescriptions with rain statistics, ultimately allowing us to quantify the coronal heating input.
Multidimensional Conservation Laws and Low Regularity Solutions
Barbara Lee Keyfitz
2007-06-16
This is the concluding report for the project, a continuation of research by Keyfitz and co-workers on multidimensional conservation laws, and applications of nonhyperbolic conservation laws in the two-fluid model for multiphase flow. The multidimensional research project was started with Suncica Canic, at the University of Houston and with Eun Heui Kim, now at California State University Long Beach. Two postdoctoral researchers, Katarina Jegdic and Allen Tesdall, also worked on this research. Jegdic's research was supported (for a total of one year) by this grant. Work on nonhyperbolic models for two-phase flows is being pursued jointly with Michael Sever, Hebrew University. Background for the project is contained in earlier reports. Note that in 2006, the project received a one-year no-cost extension that will end in September, 2007. A new proposal, for continuation of the research and for new projects, will be submitted in the Fall of 2007, with funding requested to begin in the summer of 2008. The reason for the 'funding gap' is Keyfitz's four-year stint as Director of the Fields Institute in Toronto, Canada. The research has continued, but has been supported by Canadian grant funds, as seems appropriate during this period.
Computations of entropy bounds: Multidimensional geometric methods
Makaruk, H.E.
1998-02-01
The entropy bounds for constructive upper bound on the needed number-of-bits for solving a dichotomy is represented by the quotient of two multidimensional solid volumes. For minimization of this upper bound exact calculation of the volume of this quotient is needed. Three methods for exact computing of the volume of a given nD volume are presented: (1) general method for calculation any nD volume by slicing it into volumes of decreasing dimension is presented; (2) a method applying appropriate curvilinear coordinate system is described for volume bounded by symmetrical curvilinear hypersurfaces (spheres, cones, hyperboloids, ellipsoids, cylinders, etc.); and (3) an algorithm for dividing any nD complex into simplices and computing of the volume of the simplices is presented, supplemented by a general formula for calculation of volume of an nD simplex. These mathematical methods enable exact calculation of volume of any complicated multidimensional solids. The methods allow for the calculation of the minimal volume and lead to tighter bounds on the needed number-of-bits.
Self-Motion Perception and Motion Sickness
NASA Technical Reports Server (NTRS)
Fox, Robert A.
1991-01-01
Motion sickness typically is considered a bothersome artifact of exposure to passive motion in vehicles of conveyance. This condition seldom has significant impact on the health of individuals because it is of brief duration, it usually can be prevented by simply avoiding the eliciting condition and, when the conditions that produce it are unavoidable, sickness dissipates with continued exposure. The studies conducted examined several aspects of motion sickness in animal models. A principle objective of these studies was to investigate the neuroanatomy that is important in motion sickness with the objectives of examining both the utility of putative models and defining neural mechanisms that are important in motion sickness.
Heteronuclear Multidimensional Protein NMR in a Teaching Laboratory
ERIC Educational Resources Information Center
Wright, Nathan T.
2016-01-01
Heteronuclear multidimensional NMR techniques are commonly used to study protein structure, function, and dynamics, yet they are rarely taught at the undergraduate level. Here, we describe a senior undergraduate laboratory where students collect, process, and analyze heteronuclear multidimensional NMR experiments using an unstudied Ig domain (Ig2…
Multidimensional Computerized Adaptive Testing for Indonesia Junior High School Biology
ERIC Educational Resources Information Center
Kuo, Bor-Chen; Daud, Muslem; Yang, Chih-Wei
2015-01-01
This paper describes a curriculum-based multidimensional computerized adaptive test that was developed for Indonesia junior high school Biology. In adherence to the Indonesian curriculum of different Biology dimensions, 300 items was constructed, and then tested to 2238 students. A multidimensional random coefficients multinomial logit model was…
Multidimensional Linking for Tests with Mixed Item Types
ERIC Educational Resources Information Center
Yao, Lihua; Boughton, Keith
2009-01-01
Numerous assessments contain a mixture of multiple choice (MC) and constructed response (CR) item types and many have been found to measure more than one trait. Thus, there is a need for multidimensional dichotomous and polytomous item response theory (IRT) modeling solutions, including multidimensional linking software. For example,…
Evaluating Item Fit for Multidimensional Item Response Models
ERIC Educational Resources Information Center
Zhang, Bo; Stone, Clement A.
2008-01-01
This research examines the utility of the s-x[superscript 2] statistic proposed by Orlando and Thissen (2000) in evaluating item fit for multidimensional item response models. Monte Carlo simulation was conducted to investigate both the Type I error and statistical power of this fit statistic in analyzing two kinds of multidimensional test…
Multidimensional Physical Self-Concept of Athletes with Physical Disabilities
ERIC Educational Resources Information Center
Shapiro, Deborah R.; Martin, Jeffrey J.
2010-01-01
The purposes of this investigation were first to predict reported PA (physical activity) behavior and self-esteem using a multidimensional physical self-concept model and second to describe perceptions of multidimensional physical self-concept (e.g., strength, endurance, sport competence) among athletes with physical disabilities. Athletes (N =…
The Concept of Aptitude and Multidimensional Validity Revisited.
ERIC Educational Resources Information Center
Roeser, Robert W.; Shavelson, Richard J.; Kupermintz, Haggai; Lau, Shun; Ayala, Carlos; Haydel, Angela; Schultz, Susan; Gallagher, Larry; Quihuis, Gisell
2002-01-01
Provides an overview of the approach of Richard E. Snow to the concept of aptitude and multidimensional validity and summarizes the studies in this special issue. Overall, studies confirmed the multidimensional structure of science achievement scores, the validity of some key motivational constructs for predicting achievement, and other ideas…
Entropic uncertainty relations in multidimensional position and momentum spaces
Huang Yichen
2011-05-15
Commutator-based entropic uncertainty relations in multidimensional position and momentum spaces are derived, twofold generalizing previous entropic uncertainty relations for one-mode states. They provide optimal lower bounds and imply the multidimensional variance-based uncertainty principle. The article concludes with an open conjecture.
Feng, Li; Axel, Leon; Chandarana, Hersh; Block, Kai Tobias; Sodickson, Daniel K.; Otazo, Ricardo
2015-01-01
Purpose To develop a novel framework for free-breathing MRI called XD-GRASP, which sorts dynamic data into extra motion-state dimensions using the self-navigation properties of radial imaging and reconstructs the multidimensional dataset using compressed sensing. Methods Radial k-space data are continuously acquired using the golden-angle sampling scheme and sorted into multiple motion-states based on respiratory and/or cardiac motion signals derived directly from the data. The resulting under-sampled multidimensional dataset is reconstructed using a compressed sensing approach that exploits sparsity along the new dynamic dimensions. The performance of XD-GRASP is demonstrated for free-breathing three-dimensional (3D) abdominal imaging, two-dimensional (2D) cardiac cine imaging and 3D dynamic contrast-enhanced (DCE) MRI of the liver, comparing against reconstructions without motion sorting in both healthy volunteers and patients. Results XD-GRASP separates respiratory motion from cardiac motion in cardiac imaging, and respiratory motion from contrast enhancement in liver DCE-MRI, which improves image quality and reduces motion-blurring artifacts. Conclusion XD-GRASP represents a new use of sparsity for motion compensation and a novel way to handle motions in the context of a continuous acquisition paradigm. Instead of removing or correcting motion, extra motion-state dimensions are reconstructed, which improves image quality and also offers new physiological information of potential clinical value. PMID:25809847
Multidimensional scaling of musical time estimations.
Cocenas-Silva, Raquel; Bueno, José Lino Oliveira; Molin, Paul; Bigand, Emmanuel
2011-06-01
The aim of this study was to identify the psycho-musical factors that govern time evaluation in Western music from baroque, classic, romantic, and modern repertoires. The excerpts were previously found to represent variability in musical properties and to induce four main categories of emotions. 48 participants (musicians and nonmusicians) freely listened to 16 musical excerpts (lasting 20 sec. each) and grouped those that seemed to have the same duration. Then, participants associated each group of excerpts to one of a set of sine wave tones varying in duration from 16 to 24 sec. Multidimensional scaling analysis generated a two-dimensional solution for these time judgments. Musical excerpts with high arousal produced an overestimation of time, and affective valence had little influence on time perception. The duration was also overestimated when tempo and loudness were higher, and to a lesser extent, timbre density. In contrast, musical tension had little influence. PMID:21853763
AMADA-Analysis of multidimensional astronomical datasets
NASA Astrophysics Data System (ADS)
de Souza, R. S.; Ciardi, B.
2015-09-01
We present AMADA, an interactive web application to analyze multidimensional datasets. The user uploads a simple ASCII file and AMADA performs a number of exploratory analysis together with contemporary visualizations diagnostics. The package performs a hierarchical clustering in the parameter space, and the user can choose among linear, monotonic or non-linear correlation analysis. AMADA provides a number of clustering visualization diagnostics such as heatmaps, dendrograms, chord diagrams, and graphs. In addition, AMADA has the option to run a standard or robust principal components analysis, displaying the results as polar bar plots. The code is written in R and the web interface was created using the SHINY framework. AMADA source-code is freely available at https://goo.gl/KeSPue, and the shiny-app at http://goo.gl/UTnU7I.
Multidimensional student skills with collaborative filtering
NASA Astrophysics Data System (ADS)
Bergner, Yoav; Rayyan, Saif; Seaton, Daniel; Pritchard, David E.
2013-01-01
Despite the fact that a physics course typically culminates in one final grade for the student, many instructors and researchers believe that there are multiple skills that students acquire to achieve mastery. Assessment validation and data analysis in general may thus benefit from extension to multidimensional ability. This paper introduces an approach for model determination and dimensionality analysis using collaborative filtering (CF), which is related to factor analysis and item response theory (IRT). Model selection is guided by machine learning perspectives, seeking to maximize the accuracy in predicting which students will answer which items correctly. We apply the CF to response data for the Mechanics Baseline Test and combine the results with prior analysis using unidimensional IRT.
Multidimensional multiphysics simulation of TRISO particle fuel
NASA Astrophysics Data System (ADS)
Hales, J. D.; Williamson, R. L.; Novascone, S. R.; Perez, D. M.; Spencer, B. W.; Pastore, G.
2013-11-01
Multidimensional multiphysics analysis of TRISO-coated particle fuel using the BISON finite element nuclear fuels code is described. The governing equations and material models applicable to particle fuel and implemented in BISON are outlined. Code verification based on a recent IAEA benchmarking exercise is described, and excellent comparisons are reported. Multiple TRISO-coated particles of increasing geometric complexity are considered. The code's ability to use the same algorithms and models to solve problems of varying dimensionality from 1D through 3D is demonstrated. The code provides rapid solutions of 1D spherically symmetric and 2D axially symmetric models, and its scalable parallel processing capability allows for solutions of large, complex 3D models. Additionally, the flexibility to easily include new physical and material models and straightforward ability to couple to lower length scale simulations makes BISON a powerful tool for simulation of coated-particle fuel. Future code development activities and potential applications are identified.
Multidimensional Multiphysics Simulation of TRISO Particle Fuel
J. D. Hales; R. L. Williamson; S. R. Novascone; D. M. Perez; B. W. Spencer; G. Pastore
2013-11-01
Multidimensional multiphysics analysis of TRISO-coated particle fuel using the BISON finite-element based nuclear fuels code is described. The governing equations and material models applicable to particle fuel and implemented in BISON are outlined. Code verification based on a recent IAEA benchmarking exercise is described, and excellant comparisons are reported. Multiple TRISO-coated particles of increasing geometric complexity are considered. It is shown that the code's ability to perform large-scale parallel computations permits application to complex 3D phenomena while very efficient solutions for either 1D spherically symmetric or 2D axisymmetric geometries are straightforward. Additionally, the flexibility to easily include new physical and material models and uncomplicated ability to couple to lower length scale simulations makes BISON a powerful tool for simulation of coated-particle fuel. Future code development activities and potential applications are identified.
Path integral learning of multidimensional movement trajectories
NASA Astrophysics Data System (ADS)
André, João; Santos, Cristina; Costa, Lino
2013-10-01
This paper explores the use of Path Integral Methods, particularly several variants of the recent Path Integral Policy Improvement (PI2) algorithm in multidimensional movement parametrized policy learning. We rely on Dynamic Movement Primitives (DMPs) to codify discrete and rhythmic trajectories, and apply the PI2-CMA and PIBB methods in the learning of optimal policy parameters, according to different cost functions that inherently encode movement objectives. Additionally we merge both of these variants and propose the PIBB-CMA algorithm, comparing all of them with the vanilla version of PI2. From the obtained results we conclude that PIBB-CMA surpasses all other methods in terms of convergence speed and iterative final cost, which leads to an increased interest in its application to more complex robotic problems.
Biological evolution in a multidimensional fitness landscape.
Saakian, David B; Kirakosyan, Zara; Hu, Chin-Kun
2012-09-01
We considered a multiblock molecular model of biological evolution, in which fitness is a function of the mean types of alleles located at different parts (blocks) of the genome. We formulated an infinite population model with selection and mutation, and calculated the mean fitness. For the case of recombination, we formulated a model with a multidimensional fitness landscape (the dimension of the space is equal to the number of blocks) and derived a theorem about the dynamics of initially narrow distribution. We also considered the case of lethal mutations. We also formulated the finite population version of the model in the case of lethal mutations. Our models, derived for the virus evolution, are interesting also for the statistical mechanics and the Hamilton-Jacobi equation as well.
Multi-dimensional Liquid Chromatography in Proteomics
Zhang, Xiang; Fang, Aiqin; Riley, Catherine P.; Wang, Mu; Regnier, Fred E.; Buck, Charles
2010-01-01
Proteomics is the large-scale study of proteins, particularly their expression, structures and functions. This still-emerging combination of technologies aims to describe and characterize all expressed proteins in a biological system. Because of upper limits on mass detection of mass spectrometers, proteins are usually digested into peptides and the peptides are then separated, identified and quantified from this complex enzymatic digest. The problem in digesting proteins first and then analyzing the peptide cleavage fragments by mass spectrometry is that huge numbers of peptides are generated that overwhelm direct mass spectral analyses. The objective in the liquid chromatography approach to proteomics is to fractionate peptide mixtures to enable and maximize identification and quantification of the component peptides by mass spectrometry. This review will focus on existing multidimensional liquid chromatographic (MDLC) platforms developed for proteomics and their application in combination with other techniques such as stable isotope labeling. We also provide some perspectives on likely future developments. PMID:20363391
Multidimensional Scaling Visualization Using Parametric Entropy
NASA Astrophysics Data System (ADS)
Lopes, António M.; Tenreiro Machado, J. A.; Galhano, Alexandra M.
2015-12-01
This paper studies complex systems using a generalized multidimensional scaling (MDS) technique. Complex systems are characterized by time-series responses, interpreted as a manifestation of their dynamics. Two types of time-series are analyzed, namely 18 stock markets and the gross domestic product per capita of 18 countries. For constructing the MDS charts, indices based on parametric entropies are adopted. Multiparameter entropies allow the variation of the parameters leading to alternative sets of charts. The final MDS maps are then assembled by means of Procrustes’ method that maximizes the fit between the individual charts. Therefore, the proposed method can be interpreted as a generalization to higher dimensions of the standard technique that represents (and discretizes) items by means of single “points” (i.e. zero-dimensional “objects”). The MDS plots, involving one-, two- and three-dimensional “objects”, reveal a good performance in capturing the correlations between data.
The path decomposition expansion and multidimensional tunneling
NASA Astrophysics Data System (ADS)
Auerbach, Assa; Kivelson, S.
This paper consists of two main topics. (i) The path decomposition expansion: a new path integral technique which allows us to break configuration space into disjoint regions and express the dynamics of the full system in terms of its parts. (ii) The application of the PDX and semiclassical methods for solving quantum-mechanical tunneling problems in multidimensions. The result is a conceptually simple, computationally straightforward method for calculating tunneling effects in complicated multidimensional potentials, even in cases where the nature of the states in the classically allowed regions is nontrivial. Algorithms for computing tunneling effects in general classes of problems are obtained.In addition, we present the detailed solutions to three model problems of a tunneling coordinate coupled to a phonon. This enables us to define various well-controlled approximation schemes, which help to reduce the dimensions of complicated tunneling calculations in real physical systems.
Biological evolution in a multidimensional fitness landscape.
Saakian, David B; Kirakosyan, Zara; Hu, Chin-Kun
2012-09-01
We considered a multiblock molecular model of biological evolution, in which fitness is a function of the mean types of alleles located at different parts (blocks) of the genome. We formulated an infinite population model with selection and mutation, and calculated the mean fitness. For the case of recombination, we formulated a model with a multidimensional fitness landscape (the dimension of the space is equal to the number of blocks) and derived a theorem about the dynamics of initially narrow distribution. We also considered the case of lethal mutations. We also formulated the finite population version of the model in the case of lethal mutations. Our models, derived for the virus evolution, are interesting also for the statistical mechanics and the Hamilton-Jacobi equation as well. PMID:23030957
Multidimensional Langevin Modeling of Nonoverdamped Dynamics
NASA Astrophysics Data System (ADS)
Schaudinnus, Norbert; Bastian, Björn; Hegger, Rainer; Stock, Gerhard
2015-07-01
Based on a given time series, data-driven Langevin modeling aims to construct a low-dimensional dynamical model of the underlying system. When dealing with physical data as provided by, e.g., all-atom molecular dynamics simulations, effects due to small damping may be important to correctly describe the statistics (e.g., the energy landscape) and the dynamics (e.g., transition times). To include these effects in a dynamical model, an algorithm that propagates a second-order Langevin scheme is derived, which facilitates the treatment of multidimensional data. Adopting extensive molecular dynamics simulations of a peptide helix, a five-dimensional model is constructed that successfully forecasts the complex structural dynamics of the system. Neglect of small damping effects, on the other hand, is shown to lead to significant errors and inconsistencies.
A study of multidimensional modeling approaches for data warehouse
NASA Astrophysics Data System (ADS)
Yusof, Sharmila Mat; Sidi, Fatimah; Ibrahim, Hamidah; Affendey, Lilly Suriani
2016-08-01
Data warehouse system is used to support the process of organizational decision making. Hence, the system must extract and integrate information from heterogeneous data sources in order to uncover relevant knowledge suitable for decision making process. However, the development of data warehouse is a difficult and complex process especially in its conceptual design (multidimensional modeling). Thus, there have been various approaches proposed to overcome the difficulty. This study surveys and compares the approaches of multidimensional modeling and highlights the issues, trend and solution proposed to date. The contribution is on the state of the art of the multidimensional modeling design.
Multidimensional displacement vector measurement methods utilizing instantaneous phase.
Sumi, Chikayoshi
2005-01-01
In this report, we propose two new methods for measuring multidimensional displacement vector using instantaneous ultrasound signal phase, i.e., the multidimensional autocorrelation method and the multidimensional Doppler's method. In order to realize high measurement accuracy, respective displacement vector measurement methods are combined with our proposed useful lateral modulation method, i.e., the lateral Gaussian envelop cosine modulation method. We further report measurement accuracy evaluated through simulations. These methods can be applied to tissue strain measurement, blood flow measurement, sonar measurement, etc.
NASA Astrophysics Data System (ADS)
Bodin, Jacques
2015-03-01
In this study, new multi-dimensional time-domain random walk (TDRW) algorithms are derived from approximate one-dimensional (1-D), two-dimensional (2-D), and three-dimensional (3-D) analytical solutions of the advection-dispersion equation and from exact 1-D, 2-D, and 3-D analytical solutions of the pure-diffusion equation. These algorithms enable the calculation of both the time required for a particle to travel a specified distance in a homogeneous medium and the mass recovery at the observation point, which may be incomplete due to 2-D or 3-D transverse dispersion or diffusion. The method is extended to heterogeneous media, represented as a piecewise collection of homogeneous media. The particle motion is then decomposed along a series of intermediate checkpoints located on the medium interface boundaries. The accuracy of the multi-dimensional TDRW method is verified against (i) exact analytical solutions of solute transport in homogeneous media and (ii) finite-difference simulations in a synthetic 2-D heterogeneous medium of simple geometry. The results demonstrate that the method is ideally suited to purely diffusive transport and to advection-dispersion transport problems dominated by advection. Conversely, the method is not recommended for highly dispersive transport problems because the accuracy of the advection-dispersion TDRW algorithms degrades rapidly for a low Péclet number, consistent with the accuracy limit of the approximate analytical solutions. The proposed approach provides a unified methodology for deriving multi-dimensional time-domain particle equations and may be applicable to other mathematical transport models, provided that appropriate analytical solutions are available.
Multi-dimensional tunnelling and complex momentum
NASA Technical Reports Server (NTRS)
Bowcock, Peter; Gregory, Ruth
1991-01-01
The problem of modeling tunneling phenomena in more than one dimension is examined. It is found that existing techniques are inadequate in a wide class of situations, due to their inability to deal with concurrent classical motion. The generalization of these methods to allow for complex momenta is shown, and improved techniques are demonstrated with a selection of illustrative examples. Possible applications are presented.
NASA Multidimensional Stirling Convertor Code Developed
NASA Technical Reports Server (NTRS)
Tew, Roy C.; Thieme, Lanny G.
2004-01-01
A high-efficiency Stirling Radioisotope Generator (SRG) for use on potential NASA Space Science missions is being developed by the Department of Energy, Lockheed Martin, Stirling Technology Company, and the NASA Glenn Research Center. These missions may include providing spacecraft onboard electric power for deep space missions or power for unmanned Mars rovers. Glenn is also developing advanced technology for Stirling convertors, aimed at substantially improving the specific power and efficiency of the convertor and the overall power system. Performance and mass improvement goals have been established for second- and third-generation Stirling radioisotope power systems. Multiple efforts are underway to achieve these goals, both in house at Glenn and under various grants and contracts. These efforts include the development of a multidimensional Stirling computational fluid dynamics code, high-temperature materials, advanced controllers, an end-to-end system dynamics model, low-vibration techniques, advanced regenerators, and a lightweight convertor. Under a NASA grant, Cleveland State University (CSU) and its subcontractors, the University of Minnesota (UMN) and Gedeon Associates, have developed a twodimensional computer simulation of a CSUmod Stirling convertor. The CFD-ACE commercial software developed by CFD Research Corp. of Huntsville, Alabama, is being used. The CSUmod is a scaled version of the Stirling Technology Demonstrator Convertor (TDC), which was designed and fabricated by the Stirling Technology Company and is being tested by NASA. The schematic illustrates the structure of this model. Modeled are the fluid-flow and heat-transfer phenomena that occur in the expansion space, the heater, the regenerator, the cooler, the compression space, the surrounding walls, and the moving piston and displacer. In addition, the overall heat transfer, the indicated power, and the efficiency can be calculated. The CSUmod model is being converted to a two
Exploring multidimensional free energy surfaces of peptides
NASA Astrophysics Data System (ADS)
Wang, Yan; Kuczera, Krzysztof
1997-03-01
A new statistical mechanics thermodynamic integration method is presented, enabling exploration of multidimensional conformational free energy surfaces of large flexible molecules. In this approach a single molecular dynamics simulation in which a set of coordinates has been constrained to fixed values yields the free energy gradient with respect to all coordinates in the set. The availability of the multidimensional gradient opens new possibilities for exploration of molecular conformational free energy surfaces, including free energy optimization to locate free energy minima, calculation of higher free energy derivatives, and finding optimal free energy paths between states. Additionally, choosing of all "soft" degrees of freedom as the constrained set leads to accelerated convergence of averages, effectively overcoming the sampling problem of free energy simulations. Two applications of the method are presented: Helical states of model peptides. For model peptides (Ala)n and (Aib)n where n=6,8,10 and Aib is α-methylalanine in vacuum, free energy maps and free energy optimization in φ-ψ space are used to locate free energy minima corresponding to α-, π- and 3_10-helical structures. The stability of the minima is characterized by calculating numerical second derivatives of the free energy. Free energy decomposition is employed to reveal the molecular mechanism for the improved stability of the 3_10h relative to the ah in Aib-containing peptides. DPDPE peptide pre-organization. For the linear form of the opioid peptide DPDPE in aqueous solution, the effective local sampling made possible by fixing all soft degrees of freedom is used to calculate the free energy difference between the open and cyclic-like structures, providing an estimate of the free energy of pre-organizing the peptide for disulfide bond formation. The open structure was found to be more stable by 4.0 ± 0.8 kcal/mol. The cyclic-like conformation was much better solvated than the open
The Measurement of Self-Rated Depression: A Multidimensional Approach.
ERIC Educational Resources Information Center
Bolon, Kevin; Barling, Julian
1980-01-01
Investigates the capacity of the Zung Self-Rating Depression Scale for providing specific multidimensional descriptors of depressive behavior. Ideational, physiological and behavioral depression factors were evident in data from 96 normal, white university student volunteers. (Author/RH)
Design of Multidimensional Shinnar-Le Roux RF Pulses
Ma, Chao; Liang, Zhi-Pei
2014-01-01
Purpose To generalize the conventional Shinnar-Le Roux (SLR) method for the design of multidimensional RF pulses. Methods Using echo-planar gradients, the multidimensional RF pulse design problem was converted into a series of 1D polynomial design problems. Each of the 1D polynomial design problems was solved efficiently. B0 inhomogeneity compensation and design of spatial-spectral pulses were also considered. Results The proposed method was used to design 2D excitation and refocusing pulses. The results were validated through Bloch equation simulation and experiments on a 3.0 T scanner. Large-tip-angle, equiripple-error, multidimensional excitation was achieved with ripple levels closely matching the design specifications. Conclusion The conventional SLR method can be extended to design multidimensional RF pulses. The proposed method achieves almost equiripple excitation errors, allows easy control of the tradeoff among design parameters, and is computationally efficient. PMID:24578212
A multidimensional subdiffusion model: An arbitrage-free market
NASA Astrophysics Data System (ADS)
Li, Guo-Hua; Zhang, Hong; Luo, Mao-Kang
2012-12-01
To capture the subdiffusive characteristics of financial markets, the subordinated process, directed by the inverse α-stale subordinator Sα(t) for 0 < α < 1, has been employed as the model of asset prices. In this article, we introduce a multidimensional subdiffusion model that has a bond and K correlated stocks. The stock price process is a multidimensional subdiffusion process directed by the inverse α-stable subordinator. This model describes the period of stagnation for each stock and the behavior of the dependency between multiple stocks. Moreover, we derive the multidimensional fractional backward Kolmogorov equation for the subordinated process using the Laplace transform technique. Finally, using a martingale approach, we prove that the multidimensional subdiffusion model is arbitrage-free, and also gives an arbitrage-free pricing rule for contingent claims associated with the martingale measure.
The space transformation in the simulation of multidimensional random fields
Christakos, G.
1987-01-01
Space transformations are proposed as a mathematically meaningful and practically comprehensive approach to simulate multidimensional random fields. Within this context the turning bands method of simulation is reconsidered and improved in both the space and frequency domains. ?? 1987.
Multidimensional Fourier Methods: Analysis of Internal Soliton Data and Acoustic Wave Propagation
NASA Astrophysics Data System (ADS)
Osborne, A.
2005-05-01
The aggressive pursuit of a satisfactory level of physical understanding of nonlinear oceanic wave dynamics has lead to the use of multidimensional Fourier analysis as a tool for the time series analysis of both internal wave motion and acoustic wave propagation. These new tools have arisen naturally for studies using the inverse scattering transform to particular nonlinear wave equations. When applied to the Korteweg-deVries equation, for example, one finds that the approach can be extended to arbitrarily high order. There are several advantages for using multidimensional Fourier methods over ordinary Fourier analysis: (1) fully nonlinear wave dynamics can be studied, (2) solitons become a natural component in the theory and correspond to the diagonal elements of the "Riemann matrix", (3) nonlinear interactions are accounted for by the off-diagonal elements of this matrix, (4) nonlinear acoustic modes are found to also have an (albeit static) solitonic component. These surprising results lead to new interpretations of acoustic waves propagating in the presence of a nonlinear internal wave field. One of the most important results is the implication that new nonlinear filtering techniques allow for the spectral decomposition of both the internal wave field and of the acoustic field. With regard to the acoustic field, one can foresee the application of the method to the observations of phenomena in the "hidden zones", where one would normally conclude that acoustic wave propagation does not occur.
Central Schemes for Multi-Dimensional Hamilton-Jacobi Equations
NASA Technical Reports Server (NTRS)
Bryson, Steve; Levy, Doron; Biegel, Bryan (Technical Monitor)
2002-01-01
We present new, efficient central schemes for multi-dimensional Hamilton-Jacobi equations. These non-oscillatory, non-staggered schemes are first- and second-order accurate and are designed to scale well with an increasing dimension. Efficiency is obtained by carefully choosing the location of the evolution points and by using a one-dimensional projection step. First-and second-order accuracy is verified for a variety of multi-dimensional, convex and non-convex problems.
Multidimensional Programming Methods for Energy Facility Siting: Alternative Approaches
NASA Technical Reports Server (NTRS)
Solomon, B. D.; Haynes, K. E.
1982-01-01
The use of multidimensional optimization methods in solving power plant siting problems, which are characterized by several conflicting, noncommensurable objectives is addressed. After a discussion of data requirements and exclusionary site screening methods for bounding the decision space, classes of multiobjective and goal programming models are discussed in the context of finite site selection. Advantages and limitations of these approaches are highlighted and the linkage of multidimensional methods with the subjective, behavioral components of the power plant siting process is emphasized.
ERIC Educational Resources Information Center
Tea, Peter L., Jr.
1988-01-01
Explains gyroscopic motions to college freshman or high school seniors who have learned about centripetal acceleration and the transformations of a couple. Contains several figures showing the direction of forces and motion. (YP)
Numerical approaches for multidimensional simulations of stellar explosions
NASA Astrophysics Data System (ADS)
Chen, Ke-Jung; Heger, Alexander; Almgren, Ann S.
2013-11-01
We introduce numerical algorithms for initializing multidimensional simulations of stellar explosions with 1D stellar evolution models. The initial mapping from 1D profiles onto multidimensional grids can generate severe numerical artifacts, one of the most severe of which is the violation of conservation laws for physical quantities. We introduce a numerical scheme for mapping 1D spherically-symmetric data onto multidimensional meshes so that these physical quantities are conserved. We verify our scheme by porting a realistic 1D Lagrangian stellar profile to the new multidimensional Eulerian hydro code CASTRO. Our results show that all important features in the profiles are reproduced on the new grid and that conservation laws are enforced at all resolutions after mapping. We also introduce a numerical scheme for initializing multidimensional supernova simulations with realistic perturbations predicted by 1D stellar evolution models. Instead of seeding 3D stellar profiles with random perturbations, we imprint them with velocity perturbations that reproduce the Kolmogorov energy spectrum expected for highly turbulent convective regions in stars. Our models return Kolmogorov energy spectra and vortex structures like those in turbulent flows before the modes become nonlinear. Finally, we describe approaches to determining the resolution for simulations required to capture fluid instabilities and nuclear burning. Our algorithms are applicable to multidimensional simulations besides stellar explosions that range from astrophysics to cosmology.
New methodology for multi-dimensional spinal joint testing with a parallel robot.
Walker, Matthew R; Dickey, James P
2007-03-01
Six degree-of-freedom (6DOF) robots can be used to examine joints and their mechanical properties with the spatial freedom encountered physiologically. Parallel robots are capable of 6DOF motion under large payloads making them ideal for joint testing. This study developed and assessed novel methods for spinal joint testing with a custom-built parallel robot implementing hybrid load-position control. We hypothesized these methods would allow multi-dimensional control of joint loading scenarios, resulting in physiological joint motions. Tests were performed in 3DOF and 6DOF. 3DOF methods controlled the forces and the principal moment within +/-10 N and 0.25 N m under combined bending and compressive loads. 6DOF tests required larger tolerances for convergence due to machine compliance, however expected motion patterns were still observed. The unique mechanism and control approaches show promise for enabling complex three-dimensional loading patterns for in vitro joint biomechanics, and could facilitate research using specimens with unknown, changing, or nonlinear load-deformation properties. PMID:17235615
Correlative visualization techniques for multidimensional data
NASA Technical Reports Server (NTRS)
Treinish, Lloyd A.; Goettsche, Craig
1989-01-01
Critical to the understanding of data is the ability to provide pictorial or visual representation of those data, particularly in support of correlative data analysis. Despite the advancement of visualization techniques for scientific data over the last several years, there are still significant problems in bringing today's hardware and software technology into the hands of the typical scientist. For example, there are other computer science domains outside of computer graphics that are required to make visualization effective such as data management. Well-defined, flexible mechanisms for data access and management must be combined with rendering algorithms, data transformation, etc. to form a generic visualization pipeline. A generalized approach to data visualization is critical for the correlative analysis of distinct, complex, multidimensional data sets in the space and Earth sciences. Different classes of data representation techniques must be used within such a framework, which can range from simple, static two- and three-dimensional line plots to animation, surface rendering, and volumetric imaging. Static examples of actual data analyses will illustrate the importance of an effective pipeline in data visualization system.
Multi-dimensionally encoded magnetic resonance imaging
Lin, Fa-Hsuan
2013-01-01
Magnetic resonance imaging typically achieves spatial encoding by measuring the projection of a q-dimensional object over q-dimensional spatial bases created by linear spatial encoding magnetic fields (SEMs). Recently, imaging strategies using nonlinear SEMs have demonstrated potential advantages for reconstructing images with higher spatiotemporal resolution and reducing peripheral nerve stimulation. In practice, nonlinear SEMs and linear SEMs can be used jointly to further improve the image reconstruction performance. Here we propose the multi-dimensionally encoded (MDE) MRI to map a q-dimensional object onto a p-dimensional encoding space where p > q. MDE MRI is a theoretical framework linking imaging strategies using linear and nonlinear SEMs. Using a system of eight surface SEM coils with an eight-channel RF coil array, we demonstrate the five-dimensional MDE MRI for a two-dimensional object as a further generalization of PatLoc imaging and O-space imaging. We also present a method of optimizing spatial bases in MDE MRI. Results show that MDE MRI with a higher dimensional encoding space can reconstruct images more efficiently and with a smaller reconstruction error when the k-space sampling distribution and the number of samples are controlled. PMID:22926830
Multi-dimensional cosmology and GUP
Zeynali, K.; Motavalli, H.; Darabi, F. E-mail: f.darabi@azaruniv.edu
2012-12-01
We consider a multidimensional cosmological model with FRW type metric having 4-dimensional space-time and d-dimensional Ricci-flat internal space sectors with a higher dimensional cosmological constant. We study the classical cosmology in commutative and GUP cases and obtain the corresponding exact solutions for negative and positive cosmological constants. It is shown that for negative cosmological constant, the commutative and GUP cases result in finite size universes with smaller size and longer ages, and larger size and shorter age, respectively. For positive cosmological constant, the commutative and GUP cases result in infinite size universes having late time accelerating behavior in good agreement with current observations. The accelerating phase starts in the GUP case sooner than the commutative case. In both commutative and GUP cases, and for both negative and positive cosmological constants, the internal space is stabilized to the sub-Planck size, at least within the present age of the universe. Then, we study the quantum cosmology by deriving the Wheeler-DeWitt equation, and obtain the exact solutions in the commutative case and the perturbative solutions in GUP case, to first order in the GUP small parameter, for both negative and positive cosmological constants. It is shown that good correspondence exists between the classical and quantum solutions.
Proposed empirical gas geothermometer using multidimensional approach
Supranto; Sudjatmiko; Toha, Budianto; Wintolo, Djoko; Alhamid, Idrus
1996-01-24
Several formulas of surface gas geothermometer have been developed to utilize in geothermal exploration, i.e. by D'Amore and Panichi (1980) and by Darling and Talbot (1992). This paper presents an empirical gas geothermometer formula using multidimensional approach. The formula was derived from 37 selected chemical data of the 5 production wells from the Awibengkok Geothermal Volcanic Field in West Java. Seven components, i.e., gas volume percentage, CO_{2}, H_{2}S, CH_{4}, H_{2}, N_{2}, and NH_{3}, from these data are utilize to developed three model equations which represent relationship between temperature and gas compositions. These formulas are then tested by several fumarolic chemical data from Sibual-buali Area (North Sumatera) and from Ringgit Area (South Sumatera). Preliminary result indicated that gas volume percentage, H_{2}S and CO_{2} concentrations have a significant role in term of gas geothermometer. Further verification is currently in progress.
Multidimensional mass spectrometry-based shotgun lipidomics.
Wang, Miao; Han, Xianlin
2014-01-01
Multidimensional mass spectrometry-based shotgun lipidomics (MDMS-SL) has become a foundational analytical technology platform among current lipidomics practices due to its high efficiency, sensitivity, and reproducibility, as well as its broad coverage. This platform has been broadly used to determine the altered content and/or composition of lipid classes, subclasses, and individual molecular species induced by diseases, genetic manipulations, drug treatments, and aging, among others. Herein, we briefly discuss the principles underlying this technology and present a protocol for routine analysis of many of the lipid classes and subclasses covered by MDMS-SL directly from lipid extracts of biological samples. In particular, lipid sample preparation from a variety of biological materials, which is one of the key components of MDMS-SL, is described in detail. The protocol for mass spectrometric analysis can readily be expanded for analysis of other lipid classes not mentioned as long as appropriate sample preparation is conducted, and should aid researchers in the field to better understand and manage the technology for analysis of cellular lipidomes. PMID:25270931
COMMUNITY READINESS AS A MULTIDIMENSIONAL CONSTRUCT
Chilenski, Sarah M.; Greenberg, Mark T.; Feinberg, Mark E.
2008-01-01
Both the organizational studies literature and the community psychology literature discuss the importance of readiness when implementing change. Although each area emphasizes different characteristics, several common themes are present within the literature. The current study integrates and applies organizational and community psychology literature in evaluating community readiness in the context of a school–community–university collaborative prevention model. Results demonstrate (a) that there is substantial agreement between members of community prevention teams on the level of readiness of a community; (b) that readiness is a cohesive, but multidimensional, construct related to hypothesized community and individual characteristics; and (c) that there is small to moderate agreement between members of prevention teams and their “agency directors.” These results support the notion that clear “theories of change” need to be formulated before deciding how to assess community readiness, as assessments will vary due to several factors: the type of respondent, the level in which analyses are conducted, and the specific community domain (i.e., school, workplace collaboration, collaboration experience) investigated. PMID:18714368
The Path Decomposition Expansion and Multidimensional Tunneling
NASA Astrophysics Data System (ADS)
Auerbach, Assa
The dissertation consists of two main topics. (a) The Path Decomposition Expansion (PDX): A new path integral technique which allows us to break configuration space into disjoint regions, and express the dynamics of the full system in terms of its parts. (b) The application of the PDX and semiclassical methods for solving quantum -mechanical problems in multidimensions. The result is a conceptually simple, computationally straightforward method for calculating tunneling effects in complicated multidimensional potentials, even in cases where the nature of the states in the classically allowed regions in nontrivial. Algorithms for computing tunneling effects in general classes of problems are obtained. The detailed solutions to several model problems are presented. These enable us to define various well -controlled approximation schemes, which help to reduce the dimensions of complicated tunneling calculations in real physical systems. The dramatic effects of transverse fluctuations on the asymptotic behavior of the groundstate tunnel-splitting are studied also in potentials with non -quadratic minima where standard instanton techniques fail. The power of the PDX is demonstrated by a calculation of the optical absorption coefficient of trans-polyacetylene where large amplitude (non-perturbative) quantum fluctuations of the lattice play an important role in determining the sub-gap absorption tail. Good agreement with experimental data is found, and suggestions for further measurements in this regime are made.
Multidimensional time-correlated single photon counting
NASA Astrophysics Data System (ADS)
Becker, Wolfgang; Bergmann, Axel
2006-10-01
Time-correlated single photon counting (TCSPC) is based on the detection of single photons of a periodic light signal, measurement of the detection time of the photons, and the build-up of the photon distribution versus the time in the signal period. TCSPC achieves a near ideal counting efficiency and transit-time-spread-limited time resolution for a given detector. The drawback of traditional TCSPC is the low count rate, long acquisition time, and the fact that the technique is one-dimensional, i.e. limited to the recording of the pulse shape of light signals. We present an advanced TCSPC technique featuring multi-dimensional photon acquisition and a count rate close to the capability of currently available detectors. The technique is able to acquire photon distributions versus wavelength, spatial coordinates, and the time on the ps scale, and to record fast changes in the fluorescence lifetime and fluorescence intensity of a sample. Biomedical applications of advanced TCSPC techniques are time-domain optical tomography, recording of transient phenomena in biological systems, spectrally resolved fluorescence lifetime imaging, FRET experiments in living cells, and the investigation of dye-protein complexes by fluorescence correlation spectroscopy. We demonstrate the potential of the technique for selected applications.
Multidimensional In Vivo Hazard Assessment Using Zebrafish
Tanguay, Robert L.
2014-01-01
There are tens of thousands of man-made chemicals in the environment; the inherent safety of most of these chemicals is not known. Relevant biological platforms and new computational tools are needed to prioritize testing of chemicals with limited human health hazard information. We describe an experimental design for high-throughput characterization of multidimensional in vivo effects with the power to evaluate trends relating to commonly cited chemical predictors. We evaluated all 1060 unique U.S. EPA ToxCast phase 1 and 2 compounds using the embryonic zebrafish and found that 487 induced significant adverse biological responses. The utilization of 18 simultaneously measured endpoints means that the entire system serves as a robust biological sensor for chemical hazard. The experimental design enabled us to describe global patterns of variation across tested compounds, evaluate the concordance of the available in vitro and in vivo phase 1 data with this study, highlight specific mechanisms/value-added/novel biology related to notochord development, and demonstrate that the developmental zebrafish detects adverse responses that would be missed by less comprehensive testing strategies. PMID:24136191
Multidimensional thermal-chemical cookoff modeling
Baer, M.R.; Gross, R.J.; Gartling, D.K.; Hobbs, M.L.
1994-08-01
Multidimensional thermal/chemical modeling is an essential step in the development of a predictive capability for cookoff of energetic materials in systems subjected to abnormal thermal environments. COYOTE II is a state-of-the-art two- and three-dimensional finite element code for the solution of heat conduction problems including surface-to-surface thermal radiation heat transfer and decomposition chemistry. Multistep finite rate chemistry is incorporated into COYOTE II using an operator-splitting methodology; rate equations are solved element-by-element with a modified matrix-free stiff solver, CHEMEQ. COYOTE II is purposely designed with a user-oriented input structure compatible with the database, the pre-processing mesh generation, and the post-processing tools for data visualization shared with other engineering analysis codes available at Sandia National Laboratories. As demonstrated in a companion paper, decomposition during cookoff in a confined or semi-confined system leads to significant mechanical behavior. Although mechanical effect are not presently considered in COYOTE II, the formalism for including mechanics in multidimensions is under development.
Multidimensional View of the Bacterial Cytoskeleton
Celler, Katherine; Koning, Roman I.; Koster, Abraham J.
2013-01-01
The perspective of the cytoskeleton as a feature unique to eukaryotic organisms was overturned when homologs of the eukaryotic cytoskeletal elements were identified in prokaryotes and implicated in major cell functions, including growth, morphogenesis, cell division, DNA partitioning, and cell motility. FtsZ and MreB were the first identified homologs of tubulin and actin, respectively, followed by the discovery of crescentin as an intermediate filament-like protein. In addition, new elements were identified which have no apparent eukaryotic counterparts, such as the deviant Walker A-type ATPases, bactofilins, and several novel elements recently identified in streptomycetes, highlighting the unsuspected complexity of cytostructural components in bacteria. In vivo multidimensional fluorescence microscopy has demonstrated the dynamics of the bacterial intracellular world, and yet we are only starting to understand the role of cytoskeletal elements. Elucidating structure-function relationships remains challenging, because core cytoskeletal protein motifs show remarkable plasticity, with one element often performing various functions and one function being performed by several types of elements. Structural imaging techniques, such as cryo-electron tomography in combination with advanced light microscopy, are providing the missing links and enabling scientists to answer many outstanding questions regarding prokaryotic cellular architecture. Here we review the recent advances made toward understanding the different roles of cytoskeletal proteins in bacteria, with particular emphasis on modern imaging approaches. PMID:23417493
Multidimensional multiphysics simulation of nuclear fuel behavior
NASA Astrophysics Data System (ADS)
Williamson, R. L.; Hales, J. D.; Novascone, S. R.; Tonks, M. R.; Gaston, D. R.; Permann, C. J.; Andrs, D.; Martineau, R. C.
2012-04-01
Nuclear fuel operates in an environment that induces complex multiphysics phenomena, occurring over distances ranging from inter-atomic spacing to meters, and times scales ranging from microseconds to years. This multiphysics behavior is often tightly coupled and many important aspects are inherently multidimensional. Most current fuel modeling codes employ loose multiphysics coupling and are restricted to 2D axisymmetric or 1.5D approximations. This paper describes a new modeling tool able to simulate coupled multiphysics and multiscale fuel behavior, for either 2D axisymmetric or 3D geometries. Specific fuel analysis capabilities currently implemented in this tool are described, followed by a set of demonstration problems which include a 10-pellet light water reactor fuel rodlet, three-dimensional analysis of pellet clad mechanical interaction in the vicinity of a defective fuel pellet, coupled heat transfer and fission product diffusion in a TRISO-coated fuel particle, a demonstration of the ability to couple to lower-length scale models to account for material property variation with microstructural evolution, and a demonstration of the tool's ability to efficiently solve very large and complex problems using massively-parallel computing. A final section describes an early validation exercise, comparing simulation results to a light water reactor fuel rod experiment.
ERIC Educational Resources Information Center
Damonte, Kathleen
2004-01-01
One thing scientists study is how objects move. A famous scientist named Sir Isaac Newton (1642-1727) spent a lot of time observing objects in motion and came up with three laws that describe how things move. This explanation only deals with the first of his three laws of motion. Newton's First Law of Motion says that moving objects will continue…
Multidimensional analysis and probabilistic model of volcanic and seismic activities
NASA Astrophysics Data System (ADS)
Fedorov, V.
2009-04-01
. Features of spatial distribution of volcanic eruptions and earthquakes of magnitude 7 were analyzed, and those related to the Earth rotation identified. Frequencies of their spatial distribution are calculated. Using those parameters as the base, a scheme (algorithm) of probabilistic monitoring (long-range forecast) has been developed for volcanic and seismic events. Refereces (in Russian): 1. Fedorov V.M. Gravitational factors and astronomy-based chronology of processes in geospheres. Moscow University Publishing House, 2000. 368 p. 2. Fedorov V.M. Comparison between chronology of the Earth volcanic activity and characteristics of its orbital motion // Vulkanologiya i seismologiya, № 5, 2001, p. 65-67. 3. Fedorov V.M. Specific features of latitudinal distribution of volcanic eruptions// Vulkanologiya i seismologiya, № 4, 2002, p.39-43. 4. Fedorov V.M. Specific features of latitudinal distribution of endogenic relief-forming processes and the rotation of the Earth // Geomorphologiya, № 1, 2003, p.3-9. 5. Fedorov V.M. Comparison between chronology of the Earth volcanic and seismic activity and characteristics of its orbital motion // Izvestiya RAS. Ser. Geogr. № 5, 2003, p.16-20. 6. Fedorov V.M. Chronological structure and probability of volcanic events as related to tidal deformation of lithosphere // Vulkanologiya i seismologiya, № 1, 2005, p.44-50. 7. Fedorov V.M. Multidimensional analysis and a probabilistic model of the activity of endogenic relief-forming processes // Geomorphology, № 2, 2007, p. 37 - 48. 8. Fedorov V.M. Multidimensional analysis - is a spatiotemporal structure of the geodynamic activity of Earth// Vestnik Moskovskogo Universiteta; Ser. 4. Geology, № 4, 2007, p. 24-31.
Multi-dimensional single-spin nano-optomechanics with a levitated nanodiamond
NASA Astrophysics Data System (ADS)
Neukirch, Levi P.; von Haartman, Eva; Rosenholm, Jessica M.; Nick Vamivakas, A.
2015-10-01
Considerable advances made in the development of nanomechanical and nano-optomechanical devices have enabled the observation of quantum effects, improved sensitivity to minute forces, and provided avenues to probe fundamental physics at the nanoscale. Concurrently, solid-state quantum emitters with optically accessible spin degrees of freedom have been pursued in applications ranging from quantum information science to nanoscale sensing. Here, we demonstrate a hybrid nano-optomechanical system composed of a nanodiamond (containing a single nitrogen-vacancy centre) that is levitated in an optical dipole trap. The mechanical state of the diamond is controlled by modulation of the optical trapping potential. We demonstrate the ability to imprint the multi-dimensional mechanical motion of the cavity-free mechanical oscillator into the nitrogen-vacancy centre fluorescence and manipulate the mechanical system's intrinsic spin. This result represents the first step towards a hybrid quantum system based on levitating nanoparticles that simultaneously engages optical, phononic and spin degrees of freedom.
A multidimensional finite element method for CFD
NASA Technical Reports Server (NTRS)
Pepper, Darrell W.; Humphrey, Joseph W.
1991-01-01
A finite element method is used to solve the equations of motion for 2- and 3-D fluid flow. The time-dependent equations are solved explicitly using quadrilateral (2-D) and hexahedral (3-D) elements, mass lumping, and reduced integration. A Petrov-Galerkin technique is applied to the advection terms. The method requires a minimum of computational storage, executes quickly, and is scalable for execution on computer systems ranging from PCs to supercomputers.
Intramolecular motion in DIET: Desorption and dissociation of chemisorbed ammonia
NASA Astrophysics Data System (ADS)
Burns, A. R.; Stechel, E. B.; Jennison, D. R.
1995-06-01
We show that quantum-specific detection of DIET processes of polyatomic adsorbates reveals the multidimensional dynamics of intramolecular motion. Specifically, we present an analysis of the 6-350 eV electron-induced desorption and dissociation of chemisorbed NH 3 and ND 3 on Pt(1 1 1). State-selective detection of the neutral DIET products is accomplished by 2 + 1 resonance-enhanced multiphoton ionization (REMPI). Desorption and dissociation occur as a result of distinct electronic excitations that result in different, uncoupled, modes of intramolecular motion. We find that desorption results from 3a 1-1-induced inversion motion. Trajectories on a two-dimensional potential energy surface reveal that the excited molecule fully inverts; upon deexcitation, the inverted molecule is sufficiently high on the hard wall of the substrate interaction to have enough energy to desorb. Given the short excitation lifetime, the time scale in which the (H) D atoms reach the inversion geometry directly affects the desorption yield and results in an appreciable enhancement of NH 3 desorption over that of ND 3. In general, multidimensional molecule-surface potential energy surfaces should be considered in DIET processes involving molecular adsorbates.
Dynamics of rhenium photocatalysts revealed through ultrafast multidimensional spectroscopy.
Kiefer, Laura M; King, John T; Kubarych, Kevin J
2015-04-21
Rhenium catalysts have shown promise to promote carbon neutrality by reducing a prominent greenhouse gas, CO2, to CO and other starting materials. Much research has focused on identifying intermediates in the photocatalysis mechanism as well as time scales of relevant ultrafast processes. Recent studies have implemented multidimensional spectroscopies to characterize the catalyst's ultrafast dynamics as it undergoes the many steps of its photocycle. Two-dimensional infrared (2D-IR) spectroscopy is a powerful method to obtain molecular structure information while extracting time scales of dynamical processes with ultrafast resolution. Many observables result from 2D-IR experiments including vibrational lifetimes, intramolecular redistribution time scales, and, unique to 2D-IR, spectral diffusion, which is highly sensitive to solute-solvent interactions and motional dynamics. Spectral diffusion, a measure of how long a vibrational mode takes to sample its frequency space due to multiple solvent configurations, has various contributing factors. Properties of the solvent, the solute's structural flexibility, and electronic properties, as well as interactions between the solvent and solute, complicate identifying the origin of the spectral diffusion. With carefully chosen experiments, however, the source of the spectral diffusion can be unveiled. Within the context of a considerable body of previous work, here we discuss the spectral diffusion of several rhenium catalysts at multiple stages in the catalysis. These studies were performed in multiple polar liquids to aid in discovering the contributions of the solvent. We also performed electronic ground state 2D-IR and electronic excited state transient-2D-IR experiments to observe how spectral diffusion changes upon electronic excitation. Our results indicate that with the original Lehn catalyst in THF, relative to the ground state, the spectral diffusion slows by a factor of 3 in the equilibrated triplet metal
Information theoretic approaches to multidimensional neural computations
NASA Astrophysics Data System (ADS)
Fitzgerald, Jeffrey D.
Many systems in nature process information by transforming inputs from their environments into observable output states. These systems are often difficult to study because they are performing computations on multidimensional inputs with many degrees of freedom using highly nonlinear functions. The work presented in this dissertation deals with some of the issues involved with characterizing real-world input/output systems and understanding the properties of idealized systems using information theoretic methods. Using the principle of maximum entropy, a family of models are created that are consistent with certain measurable correlations from an input/output dataset but are maximally unbiased in all other respects, thereby eliminating all unjustified assumptions about the computation. In certain cases, including spiking neurons, we show that these models also minimize the mutual information. This property gives one the advantage of being able to identify the relevant input/output statistics by calculating their information content. We argue that these maximum entropy models provide a much needed quantitative framework for characterizing and understanding sensory processing neurons that are selective for multiple stimulus features. To demonstrate their usefulness, these ideas are applied to neural recordings from macaque retina and thalamus. These neurons, which primarily respond to two stimulus features, are shown to be well described using only first and second order statistics, indicating that their firing rates encode information about stimulus correlations. In addition to modeling multi-feature computations in the relevant feature space, we also show that maximum entropy models are capable of discovering the relevant feature space themselves. This technique overcomes the disadvantages of two commonly used dimensionality reduction methods and is explored using several simulated neurons, as well as retinal and thalamic recordings. Finally, we ask how neurons in a
Multidimensional coherent spectroscopy of a semiconductor microcavity
NASA Astrophysics Data System (ADS)
Wilmer, Brian L.; Passmann, Felix; Gehl, Michael; Khitrova, Galina; Bristow, Alan D.
2016-03-01
Multidimensional coherent spectroscopy maps the detuning dependence of the upper (UP) and lower (LP) excitonpolariton branches1 in a wedged microcavity with a single InGaAs quantum well at 5 K. Features on the diagonal correspond to intra-action coherences of the UP and LP branches. Off-diagonal peaks are interaction coherences between the UP and LP branches. With increasing detuning (Δ), all peaks move to higher energy, the exciton-like (EEX) and cavity-like (Eγ) modes swap position and have maximum intensity near the anti-crossing at Δ=0. An isolated biexciton (B) is only seen at Δ<0, separated by a binding energy of approximately 2 meV. For Δ>0, the spectral weight of the off-diagonal features swap, as the LP and B come into resonance. This indicates that the off-diagonal features are sensitive to the interactions including two-quantum contributions and that a situation similar to a Feshbach resonance exists.2 Polarization of two-quantum contributions show spin sensitive two-polariton and new biexciton correlations. The latter likely influence the Feshbach resonance between biexcitons and two-polariton states. The two-quantum signatures also demonstate that biexcitons perturb the light-matter coupling in the microcavity to reduce the mixed two-polariton contributions. Detuning dependence of zero-quantum contributions show Raman-like coherences that are enhanced near zero detuning. Asymmetry of the Raman coherences are indicative of many-body interactions, which also grow stronger as the light-matter interactions are enhanced near zero deuning.
Multidimensional radiative effects in supercritical shocks
NASA Astrophysics Data System (ADS)
Leygnac, S.; Lanz, T.; Stehlé, C.; Michaut, C.; Korĉáková, D.
Recent radiative shocks experiments performed on the LULI laser at Ecole Polytechnique in France (Fleury et al., Lasers and Particle Beams 20, 263, 2002) put in evidence a supercritical shock wave in a xenon gas cell. The structure of these shocks is quite similar to those of accretion shock wave in the case of stellar formation, as indicated in Stehlé and Chieze (SF2A - Paris proceedings, 2002). Some points require further studies like the contribution of the gas excitation/ionization energy to the compression ratio and the understanding of the discrepancy, which was noted between the velocity of the radiative precursor in the experiment and in the 1D simulation. Thus, to understand the physics of the radiative shock waves, the academic case of the stationary shock is particularly interesting. We have thus studied the structure of a radiative shock wave which propagates in an ionized gas. We study the extended Rankine Hugoniot equations in various media with inclusion of radiation pressure and energy and study also the extension of the radiative precursor in the diffusion approximation. We also study the equations of multidimensional radiative transfer for a snapshot of the experimental shock in xenon in order to quantify the radiative losses in the finite experimental cell. This academic approach will help to improve the knowledge of the physical processes which take place in radiative shocks of astrophysical interest, like in the birth and death of stars, and prepare ourselves to define appropriate experiments on future high power lasers like LIL and LMJ in Bordeaux.
NASA Technical Reports Server (NTRS)
Park, Brian Vandellyn
1993-01-01
The Neutral Body Posture experienced in microgravity creates a biomechanical equilibrium by enabling the internal forces within the body to find their own balance. A patented reclining chair based on this posture provides a minimal stress environment for interfacing with computer systems for extended periods. When the chair is mounted on a 3 or 6 axis motion platform, a generic motion simulator for simulated digital environments is created. The Personal Motion Platform provides motional feedback to the occupant in synchronization with their movements inside the digital world which enhances the simulation experience. Existing HMD based simulation systems can be integrated to the turnkey system. Future developments are discussed.
Graphical Representation of Proximity Measures for Multidimensional Data
Zand, Martin S.; Wang, Jiong; Hilchey, Shannon
2015-01-01
We describe the use of classical and metric multidimensional scaling methods for graphical representation of the proximity between collections of data consisting of cases characterized by multidimensional attributes. These methods can preserve metric differences between cases, while allowing for dimensional reduction and projection to two or three dimensions ideal for data exploration. We demonstrate these methods with three datasets for: (i) the immunological similarity of influenza proteins measured by a multidimensional assay; (ii) influenza protein sequence similarity; and (iii) reconstruction of airport-relative locations from paired proximity measurements. These examples highlight the use of proximity matrices, eigenvalues, eigenvectors, and linear and nonlinear mappings using numerical minimization methods. Some considerations and caveats for each method are also discussed, and compact Mathematica programs are provided. PMID:26692757
The acquisition of multidimensional NMR spectra within a single scan
Frydman, Lucio; Scherf, Tali; Lupulescu, Adonis
2002-01-01
A scheme enabling the complete sampling of multidimensional NMR domains within a single continuous acquisition is introduced and exemplified. Provided that an analyte's signal is sufficiently strong, the acquisition time of multidimensional NMR experiments can thus be shortened by orders of magnitude. This could enable the characterization of transient events such as proteins folding, 2D NMR experiments on samples being chromatographed, bring the duration of higher dimensional experiments (e.g., 4D NMR) into the lifetime of most proteins under physiological conditions, and facilitate the incorporation of spectroscopic 2D sequences into in vivo imaging investigations. The protocol is compatible with existing multidimensional pulse sequences and can be implemented by using conventional hardware; its performance is exemplified here with a variety of homonuclear 2D NMR acquisitions. PMID:12461169
Formalism for Hypercomplex Multidimensional NMR Employing Partial-Component Subsampling
Schuyler, Adam D; Maciejewski, Mark W; Stern, Alan S; Hoch, Jeffrey C
2012-01-01
Multidimensional NMR spectroscopy typically employs phase-sensitive detection, which results in hypercomplex data (and spectra) when utilized in more than one dimension. Nonuniform sampling approaches have become commonplace in multidimensional NMR, enabling dramatic reductions in experiment time, increases in sensitivity and/or increases in resolution. In order to utilize nonuniform sampling optimally, it is necessary to characterize the relationship between the spectrum of a uniformly sampled data set and the spectrum of a subsampled data set. In this work we construct an algebra of hypercomplex numbers suitable for representing multidimensional NMR data along with partial-component nonuniform sampling (i.e. the hypercomplex components of data points are subsampled). This formalism leads to a modified DFT–convolution relationship involving a partial-component, hypercomplex point-spread function set. The framework presented here is essential for the continued development and appropriate characterization of partial-component nonuniform sampling. PMID:23246651
Quantum and Multidimensional Explanations in a Neurobiological Context of Mind.
Korf, Jakob
2015-08-01
This article examines the possible relevance of physical-mathematical multidimensional or quantum concepts aiming at understanding the (human) mind in a neurobiological context. Some typical features of the quantum and multidimensional concepts are briefly introduced, including entanglement, superposition, holonomic, and quantum field theories. Next, we consider neurobiological principles, such as the brain and its emerging (physical) mind, evolutionary and ontological origins, entropy, syntropy/neg-entropy, causation, and brain energy metabolism. In many biological processes, including biochemical conversions, protein folding, and sensory perception, the ubiquitous involvement of quantum mechanisms is well recognized. Quantum and multidimensional approaches might be expected to help describe and model both brain and mental processes, but an understanding of their direct involvement in mental activity, that is, without mediation by molecular processes, remains elusive. More work has to be done to bridge the gap between current neurobiological and physical-mathematical concepts with their associated quantum-mind theories.
Motion compensator for holographic motion picture camera
NASA Technical Reports Server (NTRS)
Kurtz, R. L.
1973-01-01
When reference beam strikes target it undergoes Doppler shift dependent upon target velocity. To compensate, object beam is first reflected from rotating cylinder that revolves in direction opposite to target but at same speed. When beam strikes target it is returned to original frequency and is in phase with reference beam. Alternatively this motion compensator may act on reference beam.
Seeing blur: 'motion sharpening' without motion.
Georgeson, Mark A; Hammett, Stephen T
2002-01-01
It is widely supposed that things tend to look blurred when they are moving fast. Previous work has shown that this is true for sharp edges but, paradoxically, blurred edges look sharper when they are moving than when stationary. This is 'motion sharpening'. We show that blurred edges also look up to 50% sharper when they are presented briefly (8-24 ms) than at longer durations (100-500 ms) without motion. This argues strongly against high-level models of sharpening based specifically on compensation for motion blur. It also argues against a recent, low-level, linear filter model that requires motion to produce sharpening. No linear filter model can explain our finding that sharpening was similar for sinusoidal and non-sinusoidal gratings, since linear filters can never distort sine waves. We also conclude that the idea of a 'default' assumption of sharpness is not supported by experimental evidence. A possible source of sharpening is a nonlinearity in the contrast response of early visual mechanisms to fast or transient temporal changes, perhaps based on the magnocellular (M-cell) pathway. Our finding that sharpening is not diminished at low contrast sets strong constraints on the nature of the nonlinearity. PMID:12137571
Measurement Error, Multidimensionality, and Scale Shrinkage: A Reply to Yen and Burket.
ERIC Educational Resources Information Center
Camilli, Gregory
1999-01-01
Yen and Burket suggested that shrinkage in vertical equating cannot be understood apart from multidimensionality. Reviews research on reliability, multidimensionality, and scale shrinkage, and explores issues of practical importance to educators. (SLD)
ERIC Educational Resources Information Center
Ashbrook, Peggy
2008-01-01
Objects in motion attract children. The following activity helps children explore the motion of bodies riding in a vehicle and safely demonstrates the answer to their questions, "Why do I need a seatbelt?" Children will enjoy moving the cup around, even if all they "see" is a cup rather than understanding it represents a car. They will understand…
NASA Technical Reports Server (NTRS)
1974-01-01
The use of optical data processing (ODP) techniques for motion analysis in two-dimensional imagery was studied. The basic feasibility of this approach was demonstrated, but inconsistent performance of the photoplastic used for recording spatial filters prevented totally automatic operation. Promising solutions to the problems encountered are discussed, and it is concluded that ODP techniques could be quite useful for motion analysis.
NASA Technical Reports Server (NTRS)
Dimeff, J.; Rositano, S.; Taylor, R. C.
1977-01-01
Mandibular motion along three axes is measured by three motion transducers on floating yoke that rests against mandible. System includes electronics to provide variety of outputs for data display and processing. Head frame is strapped to test subject's skull to provide fixed point of reference for transducers.
Motion through Syntactic Frames
ERIC Educational Resources Information Center
Feist, Michele I.
2010-01-01
The introduction of (Talmy, 1985), (Talmy, 1985) and (Talmy, 2000) typology sparked significant interest in linguistic relativity in the arena of motion language. Through careful analysis of the conflation patterns evident in the language of motion events, Talmy noted that one class of languages, V-languages, tends to encode path along with the…
ERIC Educational Resources Information Center
King, Kenneth
2005-01-01
When watching a small child with a toy car, it is seen that interest in motion comes early. Children often suggest speed through sounds such as "RRRrrrRRRooooommMMMmmmm" as the toy car is made to speed up, slow down, or accelerate through a turn. Older children start to consider force and motion studies in more detail, and experiences in school…
Aristotle, Motion, and Rhetoric.
ERIC Educational Resources Information Center
Sutton, Jane
Aristotle rejects a world vision of changing reality as neither useful nor beneficial to human life, and instead he reaffirms both change and eternal reality, fuses motion and rest, and ends up with "well-behaved" changes. This concept of motion is foundational to his world view, and from it emerges his theory of knowledge, philosophy of nature,…
41 CFR 60-30.8 - Motions; disposition of motions.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 41 Public Contracts and Property Management 1 2011-07-01 2009-07-01 true Motions; disposition of motions. 60-30.8 Section 60-30.8 Public Contracts and Property Management Other Provisions Relating to... EXECUTIVE ORDER 11246 Prehearing Procedures § 60-30.8 Motions; disposition of motions. (a) Motions....
41 CFR 60-30.8 - Motions; disposition of motions.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 41 Public Contracts and Property Management 1 2014-07-01 2014-07-01 false Motions; disposition of motions. 60-30.8 Section 60-30.8 Public Contracts and Property Management Other Provisions Relating to... EXECUTIVE ORDER 11246 Prehearing Procedures § 60-30.8 Motions; disposition of motions. (a) Motions....
41 CFR 60-30.8 - Motions; disposition of motions.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 41 Public Contracts and Property Management 1 2012-07-01 2009-07-01 true Motions; disposition of motions. 60-30.8 Section 60-30.8 Public Contracts and Property Management Other Provisions Relating to... EXECUTIVE ORDER 11246 Prehearing Procedures § 60-30.8 Motions; disposition of motions. (a) Motions....
41 CFR 60-30.8 - Motions; disposition of motions.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 41 Public Contracts and Property Management 1 2013-07-01 2013-07-01 false Motions; disposition of motions. 60-30.8 Section 60-30.8 Public Contracts and Property Management Other Provisions Relating to... EXECUTIVE ORDER 11246 Prehearing Procedures § 60-30.8 Motions; disposition of motions. (a) Motions....
41 CFR 60-30.8 - Motions; disposition of motions.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 41 Public Contracts and Property Management 1 2010-07-01 2010-07-01 true Motions; disposition of motions. 60-30.8 Section 60-30.8 Public Contracts and Property Management Other Provisions Relating to... EXECUTIVE ORDER 11246 Prehearing Procedures § 60-30.8 Motions; disposition of motions. (a) Motions....
Brownian motion goes ballistic
NASA Astrophysics Data System (ADS)
Florin, Ernst-Ludwig
2012-02-01
It is the randomness that is considered the hallmark of Brownian motion, but already in Einstein's seminal 1905 paper on Brownian motion it is implied that this randomness must break down at short time scales when the inertia of the particle kicks in. As a result, the particle's trajectories should lose its randomness and become smooth. The characteristic time scale for this transition is given by the ratio of the particle's mass to its viscous drag coefficient. For a 1 μm glass particle in water and at room temperature, this timescale is on the order of 100 ns. Early calculations, however, neglected the inertia of the liquid surrounding the particle which induces a transition from random diffusive to non-diffusive Brownian motion already at much larger timescales. In this first non-diffusive regime, particles of the same size but with different densities still move at almost the same rate as a result of hydrodynamic correlations. To observe Brownian motion that is dominated by the inertia of the particle, i.e. ballistic motion, one has to observe the particle at significantly shorter time scales on the order of nanoseconds. Due to the lack of sufficiently fast and precise detectors, such experiments were so far not possible on individual particles. I will describe how we were able to observe the transition from hydrodynamically dominated Brownian motion to ballistic Brownian motion in a liquid. I will compare our data with current theories for Brownian motion on fast timescales that take into account the inertia of both the liquid and the particle. The newly gained ability to measure the fast Brownian motion of an individual particle paves the way for detailed studies of confined Brownian motion and Brownian motion in heterogeneous media. [4pt] [1] Einstein, A. "Uber die von der molekularkinetischen Theorie der W"arme geforderte Bewegung von in ruhenden Fl"ussigkeiten suspendierten Teilchen. Ann. Phys. 322, 549--560 (1905). [0pt] [2] Lukic, B., S. Jeney, C
Stochastic ground motion simulation
Rezaeian, Sanaz; Xiaodan, Sun; Beer, Michael; Kougioumtzoglou, Ioannis A.; Patelli, Edoardo; Siu-Kui Au, Ivan
2014-01-01
Strong earthquake ground motion records are fundamental in engineering applications. Ground motion time series are used in response-history dynamic analysis of structural or geotechnical systems. In such analysis, the validity of predicted responses depends on the validity of the input excitations. Ground motion records are also used to develop ground motion prediction equations(GMPEs) for intensity measures such as spectral accelerations that are used in response-spectrum dynamic analysis. Despite the thousands of available strong ground motion records, there remains a shortage of records for large-magnitude earthquakes at short distances or in specific regions, as well as records that sample specific combinations of source, path, and site characteristics.
Motion sickness in migraine sufferers.
Marcus, Dawn A; Furman, Joseph M; Balaban, Carey D
2005-12-01
Motion sickness commonly occurs after exposure to actual motion, such as car or amusement park rides, or virtual motion, such as panoramic movies. Motion sickness symptoms may be disabling, significantly limiting business, travel and leisure activities. Motion sickness occurs in approximately 50% of migraine sufferers. Understanding motion sickness in migraine patients may improve understanding of the physiology of both conditions. Recent literature suggests important relationships between the trigeminal system and vestibular nuclei that may have implications for both motion sickness and migraine. Studies demonstrating an important relationship between serotonin receptors and motion sickness susceptibility in both rodents and humans suggest possible new motion sickness prevention therapies.
Best Design for Multidimensional Computerized Adaptive Testing with the Bifactor Model
ERIC Educational Resources Information Center
Seo, Dong Gi; Weiss, David J.
2015-01-01
Most computerized adaptive tests (CATs) have been studied using the framework of unidimensional item response theory. However, many psychological variables are multidimensional and might benefit from using a multidimensional approach to CATs. This study investigated the accuracy, fidelity, and efficiency of a fully multidimensional CAT algorithm…
Multidimensional Measurement of Poverty among Women in Sub-Saharan Africa
ERIC Educational Resources Information Center
Batana, Yele Maweki
2013-01-01
Since the seminal work of Sen, poverty has been recognized as a multidimensional phenomenon. The recent availability of relevant databases renewed the interest in this approach. This paper estimates multidimensional poverty among women in fourteen Sub-Saharan African countries using the Alkire and Foster multidimensional poverty measures, whose…
A Multidimensional Scaling Analysis of Students' Attitudes about Science Careers
ERIC Educational Resources Information Center
Masnick, Amy M.; Valenti, S. Stavros; Cox, Brian D.; Osman, Christopher J.
2010-01-01
To encourage students to seek careers in Science, Technology, Engineering and Mathematics (STEM) fields, it is important to gauge students' implicit and explicit attitudes towards scientific professions. We asked high school and college students to rate the similarity of pairs of occupations, and then used multidimensional scaling (MDS) to create…
Turkish Validity Examination of the Multidimensional Students' Life Satisfaction Scale
ERIC Educational Resources Information Center
Irmak, Sezgin; Kuruuzum, Ayse
2009-01-01
The validation studies of the Multidimensional Students' Life Satisfaction Scale (MSLSS) have been conducted with samples from different nations but mostly from western individualistic cultures. Life satisfaction and its constructs could differ depending on cultural characteristics and life satisfaction scales should be validated in different…
An overview of multidimensional liquid phase separations in food analysis.
Franco, Maraíssa Silva; Padovan, Rodrigo Nogueira; Fumes, Bruno Henrique; Lanças, Fernando Mauro
2016-07-01
Food safety is a priority public health concern that demands analytical methods capable to detect low concentration level of contaminants (e.g. pesticides and antibiotics) in different food matrices. Due to the high complexity of these matrices, a sample preparation step is in most cases mandatory to achieve satisfactory results being usually tedious, lengthy, and prone to the introduction of errors. For this reason, many research groups have focused efforts on the development of online systems capable to do the cleanup, concentration, and separation steps at once through multidimensional separation techniques (MDS). Among several possible setups, the most popular are the multidimensional chromatographic techniques (MDC) that consist in combining more than one mobile and/or stationary phase to provide a satisfactory separation. In the present review, we selected a variety of multidimensional separation systems used for food contaminant analysis in order to discuss the instrumentation aspects, the concept of orthogonality, column approaches used in these systems, and new materials that can be used in these columns. Selected classes of contaminants present in food matrices are introduced and discussed as example of the potential applications of multidimensional liquid phase separation techniques in food safety. PMID:27030380
Multidimensional Scaling: Review and Geographical Applications, Technical Paper No. 10.
ERIC Educational Resources Information Center
Golledge, R. G.; Rushton, Gerard
The purpose of this monograph is to show that sufficient achievements in scaling applications have been made to justify serious study of scaling methodologies, particularly multidimensional scaling (MDS) as a tool for geographers. To be useful research, it was felt that the common methodological and technical problems that specialized researchers…
Multidimensional Scoring of Abilities: The Ordered Polytomous Response Case
ERIC Educational Resources Information Center
de la Torre, Jimmy
2008-01-01
Recent work has shown that multidimensionally scoring responses from different tests can provide better ability estimates. For educational assessment data, applications of this approach have been limited to binary scores. Of the different variants, the de la Torre and Patz model is considered more general because implementing the scoring procedure…
An overview of multidimensional liquid phase separations in food analysis.
Franco, Maraíssa Silva; Padovan, Rodrigo Nogueira; Fumes, Bruno Henrique; Lanças, Fernando Mauro
2016-07-01
Food safety is a priority public health concern that demands analytical methods capable to detect low concentration level of contaminants (e.g. pesticides and antibiotics) in different food matrices. Due to the high complexity of these matrices, a sample preparation step is in most cases mandatory to achieve satisfactory results being usually tedious, lengthy, and prone to the introduction of errors. For this reason, many research groups have focused efforts on the development of online systems capable to do the cleanup, concentration, and separation steps at once through multidimensional separation techniques (MDS). Among several possible setups, the most popular are the multidimensional chromatographic techniques (MDC) that consist in combining more than one mobile and/or stationary phase to provide a satisfactory separation. In the present review, we selected a variety of multidimensional separation systems used for food contaminant analysis in order to discuss the instrumentation aspects, the concept of orthogonality, column approaches used in these systems, and new materials that can be used in these columns. Selected classes of contaminants present in food matrices are introduced and discussed as example of the potential applications of multidimensional liquid phase separation techniques in food safety.
BMDS: A Collection of R Functions for Bayesian Multidimensional Scaling
ERIC Educational Resources Information Center
Okada, Kensuke; Shigemasu, Kazuo
2009-01-01
Bayesian multidimensional scaling (MDS) has attracted a great deal of attention because: (1) it provides a better fit than do classical MDS and ALSCAL; (2) it provides estimation errors of the distances; and (3) the Bayesian dimension selection criterion, MDSIC, provides a direct indication of optimal dimensionality. However, Bayesian MDS is not…
A MULTIDIMENSIONAL AND MULTIPHYSICS APPROACH TO NUCLEAR FUEL BEHAVIOR SIMULATION
R. L. Williamson; J. D. Hales; S. R. Novascone; M. R. Tonks; D. R. Gaston; C. J. Permann; D. Andrs; R. C. Martineau
2012-04-01
Important aspects of fuel rod behavior, for example pellet-clad mechanical interaction (PCMI), fuel fracture, oxide formation, non-axisymmetric cooling, and response to fuel manufacturing defects, are inherently multidimensional in addition to being complicated multiphysics problems. Many current modeling tools are strictly 2D axisymmetric or even 1.5D. This paper outlines the capabilities of a new fuel modeling tool able to analyze either 2D axisymmetric or fully 3D models. These capabilities include temperature-dependent thermal conductivity of fuel; swelling and densification; fuel creep; pellet fracture; fission gas release; cladding creep; irradiation growth; and gap mechanics (contact and gap heat transfer). The need for multiphysics, multidimensional modeling is then demonstrated through a discussion of results for a set of example problems. The first, a 10-pellet rodlet, demonstrates the viability of the solution method employed. This example highlights the effect of our smeared cracking model and also shows the multidimensional nature of discrete fuel pellet modeling. The second example relies on our the multidimensional, multiphysics approach to analyze a missing pellet surface problem. As a final example, we show a lower-length-scale simulation coupled to a continuum-scale simulation.
Multidimensional profiling of cell surface proteins and nuclear markers
Han, Ju; Chang, Hang; Andarawewa, Kumari; Yaswen, Paul; Helen Barcellos-Hoff, Mary; Parvin, Bahram
2009-01-30
Cell membrane proteins play an important role in tissue architecture and cell-cell communication. We hypothesize that segmentation and multidimensional characterization of the distribution of cell membrane proteins, on a cell-by-cell basis, enable improved classification of treatment groups and identify important characteristics that can otherwise be hidden. We have developed a series of computational steps to (i) delineate cell membrane protein signals and associate them with a specific nucleus; (ii) compute a coupled representation of the multiplexed DNA content with membrane proteins; (iii) rank computed features associated with such a multidimensional representation; (iv) visualize selected features for comparative evaluation through heatmaps; and (v) discriminate between treatment groups in an optimal fashion. The novelty of our method is in the segmentation of the membrane signal and the multidimensional representation of phenotypic signature on a cell-by-cell basis. To test the utility of this method, the proposed computational steps were applied to images of cells that have been irradiated with different radiation qualities in the presence and absence of other small molecules. These samples are labeled for their DNA content and E-cadherin membrane proteins. We demonstrate that multidimensional representations of cell-by-cell phenotypes improve predictive and visualization capabilities among different treatment groups, and identify hidden variables.
A Multidimensional Latent Trait Model for Measuring Learning and Change.
ERIC Educational Resources Information Center
Embretson, Susan E.
1991-01-01
A multidimensional model is presented for measuring learning and change based on item response theory. The model specifies a Wiener simplex pattern for involvement of initial ability and one or more modifiabilities in response potential for successive measurement occasions. Properties of the model are explored for several classical issues. (SLD)
Psychometric Properties of the Multidimensional-Multiattributional Causality Scale.
ERIC Educational Resources Information Center
Hamilton, Richard J.; Akhter, Selina
2002-01-01
Studied the construct validity of the dimensions of the Multidimensional-Multiattributional Causality Scale based on B. Wiener's attribution model (1979) in achievement and affiliation goal domains. Results for 172 New Zealand college students provide evidence that the measure is better used as a goal specific measure than a general measure. (SLD)
Multidimensional Vector Model of Stimulus-Response Compatibility
ERIC Educational Resources Information Center
Yamaguchi, Motonori; Proctor, Robert W.
2012-01-01
The present study proposes and examines the multidimensional vector (MDV) model framework as a modeling schema for choice response times. MDV extends the Thurstonian model, as well as signal detection theory, to classification tasks by taking into account the influence of response properties on stimulus discrimination. It is capable of accounting…
Assessing Multidimensional Energy Literacy of Secondary Students Using Contextualized Assessment
ERIC Educational Resources Information Center
Chen, Kuan-Li; Liu, Shiang-Yao; Chen, Po-Hsi
2015-01-01
Energy literacy is multidimensional, comprising broad content knowledge as well as affect and behavior. Our previous study has defined four core dimensions for the assessment framework, including energy concepts, reasoning on energy issues, low-carbon lifestyle, and civic responsibility for a sustainable society. The present study compiled a…
Three-Mode Multidimensional Scaling with Points of View Solutions
ERIC Educational Resources Information Center
Tzeng, Oliver C. S.; Landis, Dan
1978-01-01
Two popular models for performing multidimensional scaling, Tucker and Messick's points-of-view model, and Tucker's three mode model, are combined into a single analytic procedure, the 3M-POV model. The procedure is described and its strengths are discussed. Carroll and Chang's INDSCAL model is also mentioned. (JKS)
Reporting of Subscores Using Multidimensional Item Response Theory
ERIC Educational Resources Information Center
Haberman, Shelby J.; Sinharay, Sandip
2010-01-01
Recently, there has been increasing interest in reporting subscores. This paper examines reporting of subscores using multidimensional item response theory (MIRT) models (e.g., Reckase in "Appl. Psychol. Meas." 21:25-36, 1997; C.R. Rao and S. Sinharay (Eds), "Handbook of Statistics, vol. 26," pp. 607-642, North-Holland, Amsterdam, 2007; Beguin &…
A Review of the Brief Multidimensional Students' Life Satisfaction Scale
ERIC Educational Resources Information Center
Huebner, E. Scott; Seligson, Julie L.; Valois, Robert F.; Suldo, Shannon M.
2006-01-01
There are few psychometrically sound measures of life satisfaction suitable for children and adolescents. The purpose of this paper is to describe the rationale, development, and psychometric properties of a brief multidimensional life satisfaction scale appropriate for use with children of ages 8-18. The paper summarizes extant studies of its…
Generalizations of Paradoxical Results in Multidimensional Item Response Theory
ERIC Educational Resources Information Center
Jordan, Pascal; Spiess, Martin
2012-01-01
Maximum likelihood and Bayesian ability estimation in multidimensional item response models can lead to paradoxical results as proven by Hooker, Finkelman, and Schwartzman ("Psychometrika" 74(3): 419-442, 2009): Changing a correct response on one item into an incorrect response may produce a higher ability estimate in one dimension. Furthermore,…
Income Tax Preparation Assistance Service Learning Program: A Multidimensional Assessment
ERIC Educational Resources Information Center
Aldridge, Richard; Callahan, Richard A.; Chen, Yining; Wade, Stacy R.
2015-01-01
The authors present a multidimensional assessment of the outcomes and benefits of an income tax preparation assistance (ITPA) service learning program. They measure the perceived proximate benefits at the delivery of the service program, the actual learning outcome benefits prior to graduation, and the perceived long-term benefits from a…
Individual and Institutional Determinants of Multidimensional Poverty: A European Comparison
ERIC Educational Resources Information Center
Dewilde, Caroline
2008-01-01
In this article we evaluate to what extent between-country differences in the probability of being "multidimensional" poor can be explained by a range of "domain-specific" indicators of welfare regime arrangements. To this end, a so-called micro-macro model is estimated, testing the "independent" effect of institutions, as opposed to alternative…
Development and Validation of the Multidimensional State Boredom Scale
ERIC Educational Resources Information Center
Fahlman, Shelley A.; Mercer-Lynn, Kimberley B.; Flora, David B.; Eastwood, John D.
2013-01-01
This article describes the development and validation of the Multidimensional State Boredom Scale (MSBS)--the first and only full-scale measure of state boredom. It was developed based on a theoretically and empirically grounded definition of boredom. A five-factor structure of the scale (Disengagement, High Arousal, Low Arousal, Inattention, and…
Income and beyond: Multidimensional Poverty in Six Latin American Countries
ERIC Educational Resources Information Center
Battiston, Diego; Cruces, Guillermo; Lopez-Calva, Luis Felipe; Lugo, Maria Ana; Santos, Maria Emma
2013-01-01
This paper studies multidimensional poverty for Argentina, Brazil, Chile, El Salvador, Mexico and Uruguay for the period 1992-2006. The approach overcomes the limitations of the two traditional methods of poverty analysis in Latin America (income-based and unmet basic needs) by combining income with five other dimensions: school attendance for…
The Multi-Dimensional Demands of Reading in the Disciplines
ERIC Educational Resources Information Center
Lee, Carol D.
2014-01-01
This commentary addresses the complexities of reading comprehension with an explicit focus on reading in the disciplines. The author proposes reading as entailing multi-dimensional demands of the reader and posing complex challenges for teachers. These challenges are intensified by restrictive conceptions of relevant prior knowledge and experience…
Multidimensional Poverty in China: Findings Based on the CHNS
ERIC Educational Resources Information Center
Yu, Jiantuo
2013-01-01
This paper estimates multidimensional poverty in China by applying the Alkire-Foster methodology to the China Health and Nutrition Survey 2000-2009 data. Five dimensions are included: income, living standard, education, health and social security. Results suggest that rapid economic growth has resulted not only in a reduction in income poverty but…
Multidimensional Item Response Theory Parameter Estimation with Nonsimple Structure Items
ERIC Educational Resources Information Center
Finch, Holmes
2011-01-01
Estimation of multidimensional item response theory (MIRT) model parameters can be carried out using the normal ogive with unweighted least squares estimation with the normal-ogive harmonic analysis robust method (NOHARM) software. Previous simulation research has demonstrated that this approach does yield accurate and efficient estimates of item…
Five Evils: Multidimensional Poverty and Race in America
ERIC Educational Resources Information Center
Reeves, Richard; Rodrigue, Edward; Kneebone, Elizabeth
2016-01-01
Poverty is about a lack of money, but it's not only about that. As a lived experience, poverty is also characterized by ill health, insecurity, discomfort, isolation, and more. To put it another way: Poverty is multidimensional, and its dimensions often cluster together to intensify the negative effects of being poor. In this first of a two-part…
The Structure and Validity of the Multidimensional Social Support Questionnaire
ERIC Educational Resources Information Center
Hardesty, Patrick H.; Richardson, George B.
2012-01-01
The factor structure and concurrent validity of the Multidimensional Social Support Questionnaire, a brief measure of perceived social support for use with adolescents, was examined. Findings suggest that four dimensions of perceived social support may yield more information than assessments of the unitary construct of support. (Contains 8 tables…
The structure of multidimensional strained flames under transcritical conditions
NASA Astrophysics Data System (ADS)
Pons, L.; Darabiha, N.; Candel, S.; Schmitt, T.; Cuenot, B.
2009-06-01
Strained flames are commonly used to study the structure of reactive layers and describe the local properties of turbulent combustion. This model is attractive because constant strain rate flames only depend on a transverse coordinate and can be treated as a one-dimensional problem. This configuration is considered in a multidimensional context in which the strained flow is obtained by two counterflowing streams of reactants. It is used to examine the structure of transcritical strained flames in which one or two reactants are injected at a high pressure exceeding the critical value while their temperature is below the critical value. Calculations are carried out in a two-dimensional domain to test numerical models developed for multidimensional simulations and test thermodynamic and transport models devised to deal with high pressure real gas effects. Multidimensional strained flame calculations carried out in this study serve to check the validity of a new version of a Navier-Stokes flow solver (AVBP) conceived to deal with transcritical combustion of interest to liquid propellant rocket applications. This article describes the basic elements of such simulations and discusses results of calculations. It is shown that the calculated multidimensional strained flames have the expected features in terms of structure and response to the imposed strain rate. To cite this article: L. Pons et al., C. R. Mecanique 337 (2009).
Multidimensional Model of Trauma and Correlated Antisocial Personality Disorder
ERIC Educational Resources Information Center
Martens, Willem H. J.
2005-01-01
Many studies have revealed an important relationship between psychosocial trauma and antisocial personality disorder. A multidimensional model is presented which describes the psychopathological route from trauma to antisocial development. A case report is also included that can illustrate the etiological process from trauma to severe antisocial…
Multi-Dimensional Models for Teaching Deaf-Blind Children.
ERIC Educational Resources Information Center
Baud, Hank, Ed.; Garrett, Jeff, Ed.
Presented are five papers on multidimensional teaching models presented at a workshop for professionals serving deaf-blind children. In "Interpretation of Visual Reports", M. Efron discusses procedures for improving visual diagnosis and provides a questionnaire format for an educationally oriented vision report. M. Marshall, in her paper entitled…
Educational Mismatch of Graduates: A Multidimensional and Fuzzy Indicator
ERIC Educational Resources Information Center
Betti, Gianni; D'Agostino, Antonella; Neri, Laura
2011-01-01
In this paper we attempt to measure the educational mismatch, seen as a problem of overeducation, using a multidimensional and fuzzy methodology. Educational mismatch can be difficult to measure because many factors can converge to its definition and the traditional unidimensional indicators presented in literature can offer a restricted view of…
Linear and Nonlinear Thinking: A Multidimensional Model and Measure
ERIC Educational Resources Information Center
Groves, Kevin S.; Vance, Charles M.
2015-01-01
Building upon previously developed and more general dual-process models, this paper provides empirical support for a multidimensional thinking style construct comprised of linear thinking and multiple dimensions of nonlinear thinking. A self-report assessment instrument (Linear/Nonlinear Thinking Style Profile; LNTSP) is presented and…
The Multidimensionality of Calling: Conceptualization, Measurement and a Bicultural Perspective
ERIC Educational Resources Information Center
Hagmaier, Tamara; Abele, Andrea E.
2012-01-01
The experience of a calling may be seen as the ultimate form of subjective career success that has many positive consequences for individuals and organizations. We are here concerned with the conceptualization of a new multidimensional measure of calling, the MCM. In the first two studies we employed a qualitative approach and came up with five…
Analysis of stock market indices through multidimensional scaling
NASA Astrophysics Data System (ADS)
Machado, J. Tenreiro; Duarte, Fernando B.; Duarte, Gonçalo Monteiro
2011-12-01
We propose a graphical method to visualize possible time-varying correlations between fifteen stock market values. The method is useful for observing stable or emerging clusters of stock markets with similar behaviour. The graphs, originated from applying multidimensional scaling techniques (MDS), may also guide the construction of multivariate econometric models.
ERIC Educational Resources Information Center
Ding, Cody
2012-01-01
There has been considerable debate over the ways in which children's early literacy skills develop over time. Using confirmatory multidimensional scaling (MDS) growth analysis, this paper directly tested the hypothesis of a cumulative trajectory versus a compensatory trajectory of development in early literacy skills among a group of 1233…
Examining the Reliability of Student Growth Percentiles Using Multidimensional IRT
ERIC Educational Resources Information Center
Monroe, Scott; Cai, Li
2015-01-01
Student growth percentiles (SGPs, Betebenner, 2009) are used to locate a student's current score in a conditional distribution based on the student's past scores. Currently, following Betebenner (2009), quantile regression (QR) is most often used operationally to estimate the SGPs. Alternatively, multidimensional item response theory (MIRT) may…
The Relationship between Anxiety and Stuttering: A Multidimensional Approach
ERIC Educational Resources Information Center
Ezrati-Vinacour, Ruth; Levin, Iris
2004-01-01
The relationship between anxiety and stuttering is equivocal from both clinical and empirical perspectives. This study examined the relationship within the framework of the multidimensional interaction model of anxiety that includes an approach to general anxiety in specific situations [J. Pers. Soc. Psychol. 60 (1991) 919]. Ninety-four males aged…
The Structure of Masculinity-Femininity: Multidimensionality and Gender Differences.
ERIC Educational Resources Information Center
Ratliff, Elyse Sutherland; Conley, James
1981-01-01
Investigated the structure of sex role self-descriptors. Factor analyzed responses of female and male undergraduates to the Bem Sex Role Inventory. Seven factors emerged: personal warmth, social dominance, autonomy, affect, masculinity-feminity, vulnerability, and responsibility. Results support a multidimensional conception of…
Evaluation of Linking Methods for Multidimensional IRT Calibrations
ERIC Educational Resources Information Center
Min, Kyung-Seok
2007-01-01
Most researchers agree that psychological/educational tests are sensitive to multiple traits, implying the need for a multidimensional item response theory (MIRT). One limitation of applying a MIRT in practice is the difficulty in establishing equivalent scales of multiple traits. In this study, a new MIRT linking method was proposed and evaluated…
Gender and Attitudes toward People Using Wheelchairs: A Multidimensional Perspective
ERIC Educational Resources Information Center
Vilchinsky, Noa; Werner, Shirli; Findler, Liora
2010-01-01
This study aims to investigate the effect of observer's gender and target's gender on attitudes toward people who use wheelchairs due to a physical disability. Four hundred four Jewish Israeli students without disabilities completed the "Multidimensional Attitudes Scale Toward Persons With Disabilities" (MAS). Initially, confirmatory factor…
The Multidimensional Structure of Verbal Comprehension Test Items.
ERIC Educational Resources Information Center
Peled, Zimra
1984-01-01
The multidimensional structure of verbal comprehension test items was investigated. Empirical evidence was provided to support the theory that item tasks are multivariate-multiordered composites of faceted components: language, contextual knowledge, and cognitive operation. Linear and circular properties of cylindrical manifestation were…
A Multidimensional Approach to E-Learning Sustainability
ERIC Educational Resources Information Center
Trentin, Guglielmo, Ed.
2007-01-01
The aim of the article is to outline the possible key elements related to the sustainability of e-learning. After analyzing trends in e-learning diffusion, a multidimensional model for sustainability of e-learning innovations is presented. The proposed model is characterized by eight dimensions that are closely and mutually interrelated:…
On the Solution of NBVP for Multidimensional Hyperbolic Equations
Ashyralyev, Allaberen
2014-01-01
We are interested in studying multidimensional hyperbolic equations with nonlocal integral and Neumann or nonclassical conditions. For the approximate solution of this problem first and second order of accuracy difference schemes are presented. Stability estimates for the solution of these difference schemes are established. Some numerical examples illustrating applicability of these methods to hyperbolic problems are given. PMID:24983006
The Multidimensional Behavior Rating Scale: An Assessment Device for Depression.
ERIC Educational Resources Information Center
Rothblum, Esther D.; Green, Leon
The Multidimensional Behavior Rating Scale (MBRS) was constructed to assess symptoms of depression across seven modalities: behavior, affect, sensation, imagery, cognition, interpersonal relationship, and drugs. Subjects (N=33) were matched by level of depression on the Minnesota Multiphasic Personality Inventory Depression Scale to either a…
Extending Validity Evidence for Multidimensional Measures of Coaching Competency
ERIC Educational Resources Information Center
Myers, Nicholas D.; Wolfe, Edward W.; Maier, Kimberly S.; Feltz, Deborah L.; Reckase, Mark D.
2006-01-01
This study extended validity evidence for multidimensional measures of coaching competency derived from the Coaching Competency Scale (CCS; Myers, Feltz, Maier, Wolfe, & Reckase, 2006) by examining use of the original rating scale structure and testing how measures related to satisfaction with the head coach within teams and between teams.…
A Framework for Dimensionality Assessment for Multidimensional Item Response Models
ERIC Educational Resources Information Center
Svetina, Dubravka; Levy, Roy
2014-01-01
A framework is introduced for considering dimensionality assessment procedures for multidimensional item response models. The framework characterizes procedures in terms of their confirmatory or exploratory approach, parametric or nonparametric assumptions, and applicability to dichotomous, polytomous, and missing data. Popular and emerging…
The Multidimensionality of Child Poverty: Evidence from Afghanistan
ERIC Educational Resources Information Center
Trani, Jean-Francois; Biggeri, Mario; Mauro, Vincenzo
2013-01-01
This paper examines multidimensional poverty among children in Afghanistan using the Alkire-Foster method. Several previous studies have underlined the need to separate children from their adult nexus when studying poverty and treat them according to their own specificities. From the capability approach, child poverty is understood to be the lack…
The Multidimensional Fear of Death Scale: An Independent Analysis.
ERIC Educational Resources Information Center
Walkey, Frank H.
1982-01-01
Examined the factor structure and subscale reliabilities of an eight-dimensional measure of fear of death (the Multidimensional Fear of Death Scale) using a New Zealand sample. Comparison with the results of a United States study showed that both the subscale reliabilities and the factor structure were almost perfectly reproduced. (Author)
A General Multidimensional Model for the Measurement of Cultural Differences.
ERIC Educational Resources Information Center
Olmedo, Esteban L.; Martinez, Sergio R.
A multidimensional model for measuring cultural differences (MCD) based on factor analytic theory and techniques is proposed. The model assumes that a cultural space may be defined by means of a relatively small number of orthogonal dimensions which are linear combinations of a much larger number of cultural variables. Once a suitable,…
Multidimensional Adaptive Testing with Optimal Design Criteria for Item Selection
ERIC Educational Resources Information Center
Mulder, Joris; van der Linden, Wim J.
2009-01-01
Several criteria from the optimal design literature are examined for use with item selection in multidimensional adaptive testing. In particular, it is examined what criteria are appropriate for adaptive testing in which all abilities are intentional, some should be considered as a nuisance, or the interest is in the testing of a composite of the…
Positivity-preserving numerical schemes for multidimensional advection
NASA Technical Reports Server (NTRS)
Leonard, B. P.; Macvean, M. K.; Lock, A. P.
1993-01-01
This report describes the construction of an explicit, single time-step, conservative, finite-volume method for multidimensional advective flow, based on a uniformly third-order polynomial interpolation algorithm (UTOPIA). Particular attention is paid to the problem of flow-to-grid angle-dependent, anisotropic distortion typical of one-dimensional schemes used component-wise. The third-order multidimensional scheme automatically includes certain cross-difference terms that guarantee good isotropy (and stability). However, above first-order, polynomial-based advection schemes do not preserve positivity (the multidimensional analogue of monotonicity). For this reason, a multidimensional generalization of the first author's universal flux-limiter is sought. This is a very challenging problem. A simple flux-limiter can be found; but this introduces strong anisotropic distortion. A more sophisticated technique, limiting part of the flux and then restoring the isotropy-maintaining cross-terms afterwards, gives more satisfactory results. Test cases are confined to two dimensions; three-dimensional extensions are briefly discussed.
Image matrix processor for fast multi-dimensional computations
Roberson, G.P.; Skeate, M.F.
1996-10-15
An apparatus for multi-dimensional computation is disclosed which comprises a computation engine, including a plurality of processing modules. The processing modules are configured in parallel and compute respective contributions to a computed multi-dimensional image of respective two dimensional data sets. A high-speed, parallel access storage system is provided which stores the multi-dimensional data sets, and a switching circuit routes the data among the processing modules in the computation engine and the storage system. A data acquisition port receives the two dimensional data sets representing projections through an image, for reconstruction algorithms such as encountered in computerized tomography. The processing modules include a programmable local host, by which they may be configured to execute a plurality of different types of multi-dimensional algorithms. The processing modules thus include an image manipulation processor, which includes a source cache, a target cache, a coefficient table, and control software for executing image transformation routines using data in the source cache and the coefficient table and loading resulting data in the target cache. The local host processor operates to load the source cache with a two dimensional data set, loads the coefficient table, and transfers resulting data out of the target cache to the storage system, or to another destination. 10 figs.
Image matrix processor for fast multi-dimensional computations
Roberson, George P.; Skeate, Michael F.
1996-01-01
An apparatus for multi-dimensional computation which comprises a computation engine, including a plurality of processing modules. The processing modules are configured in parallel and compute respective contributions to a computed multi-dimensional image of respective two dimensional data sets. A high-speed, parallel access storage system is provided which stores the multi-dimensional data sets, and a switching circuit routes the data among the processing modules in the computation engine and the storage system. A data acquisition port receives the two dimensional data sets representing projections through an image, for reconstruction algorithms such as encountered in computerized tomography. The processing modules include a programmable local host, by which they may be configured to execute a plurality of different types of multi-dimensional algorithms. The processing modules thus include an image manipulation processor, which includes a source cache, a target cache, a coefficient table, and control software for executing image transformation routines using data in the source cache and the coefficient table and loading resulting data in the target cache. The local host processor operates to load the source cache with a two dimensional data set, loads the coefficient table, and transfers resulting data out of the target cache to the storage system, or to another destination.
Multidimensional representation of objects--The influence of task demands.
Goldfarb, L; Sabah, K
2016-04-01
In our daily life, we often encounter situations in which different features of several multidimensional objects must be perceived simultaneously. There are two types of environments of this kind: environments with multidimensional objects that have unique feature associations, and environments with multidimensional objects that have mixed feature associations. Recently, we (Goldfarb & Treisman, 2013) described the association effect, suggesting that the latter type causes behavioral perception difficulties. In the present study, we investigated this effect further by examining whether the effect is determined via a feedforward visual path or via a high-order task demand component. In order to test this question, in Experiment 1 a set of multidimensional objects were presented while we manipulated the letter case of a target feature, thus creating a visually different but semantically equivalent object, in terms of its identity. Similarly, in Experiment 2 artificial groups with different physical properties were created according to the task demands. The results indicated that the association effect is determined by the task demands, which create the group of reference. The importance of high-order task demand components in the association effect is further discussed, as well as the possible role of the neural synchrony of object files in explaining this effect. PMID:26163190
A Multidimensional Analysis of a Written L2 Spanish Corpus
ERIC Educational Resources Information Center
Asencion-Delaney, Yuly; Collentine, Joseph
2011-01-01
The present study adds to our understanding of how learners employ lexical and grammatical phenomena to communicate in writing in different types of interlanguage discourse. A multidimensional (factor) analysis of a corpus of L2 Spanish writing (202,241 words) generated by second- and third-year, university-level learners was performed. The…
Multidimensional Collaboration: Reflections on Action Research in a Clinical Context
ERIC Educational Resources Information Center
Gregory, Sheila; Poland, Fiona; Spalding, Nicola J.; Sargen, Kevin; McCulloch, Jane; Vicary, Penny
2011-01-01
This paper reflects on the challenges and benefits of multidimensional collaboration in an action research study to evaluate and improve preoperative education for patients awaiting colorectal surgery. Three cycles of planning, acting, observing and reflecting were designed to evaluate practice and implement change in this interactive setting,…
Integrable multidimensional gravitational and cosmological models and applications
NASA Astrophysics Data System (ADS)
Ivashchuk, V. D.; Melnikov, V. N.
2016-01-01
Two families of exact solutions in multidimensional gravity with scalar fields and fields of forms are considered: fluxbrane and black brane ones. A brief overview of main results on billiard approach for cosmological-type models with branes is also presented.
Multi-dimensional multi-species modeling of transient electrodeposition in LIGA microfabrication.
Evans, Gregory Herbert; Chen, Ken Shuang
2004-06-01
This report documents the efforts and accomplishments of the LIGA electrodeposition modeling project which was headed by the ASCI Materials and Physics Modeling Program. A multi-dimensional framework based on GOMA was developed for modeling time-dependent diffusion and migration of multiple charged species in a dilute electrolyte solution with reduction electro-chemical reactions on moving deposition surfaces. By combining the species mass conservation equations with the electroneutrality constraint, a Poisson equation that explicitly describes the electrolyte potential was derived. The set of coupled, nonlinear equations governing species transport, electric potential, velocity, hydrodynamic pressure, and mesh motion were solved in GOMA, using the finite-element method and a fully-coupled implicit solution scheme via Newton's method. By treating the finite-element mesh as a pseudo solid with an arbitrary Lagrangian-Eulerian formulation and by repeatedly performing re-meshing with CUBIT and re-mapping with MAPVAR, the moving deposition surfaces were tracked explicitly from start of deposition until the trenches were filled with metal, thus enabling the computation of local current densities that potentially influence the microstructure and frictional/mechanical properties of the deposit. The multi-dimensional, multi-species, transient computational framework was demonstrated in case studies of two-dimensional nickel electrodeposition in single and multiple trenches, without and with bath stirring or forced flow. Effects of buoyancy-induced convection on deposition were also investigated. To further illustrate its utility, the framework was employed to simulate deposition in microscreen-based LIGA molds. Lastly, future needs for modeling LIGA electrodeposition are discussed.
NASA Astrophysics Data System (ADS)
Brown, Lisa M.; Crayne, Susan
2000-05-01
In this paper, we present a visualization system and method for measuring, inspecting and analyzing motion in video. Starting from a simple motion video, the system creates a still image representation which we call a digital strobe photograph. Similar to visualization techniques used in conventional film photography to capture high-speed motion using strobe lamps or very fast shutters, and to capture time-lapse motion where the shutter is left open, this methodology creates a single image showing the motion of one or a small number of objects over time. Based on digital background subtraction, we assume that the background is stationary or at most slowing changing and that the camera position is fixed. The method is capable of displaying the motion based on a parameter indicating the time step between successive movements. It can also overcome problems of visualizing movement that is obscured by previous movements. The method is used in an educational software tool for children to measure and analyze various motions. Examples are given using simple physical objects such as balls and pendulums, astronomical events such as the path of the stars around the north pole at night, or the different types of locomotion used by snakes.
Marquette, Ian
2010-07-15
We construct integrals of motion for multidimensional classical systems from ladder operators of one-dimensional systems. This method can be used to obtain new systems with higher order integrals. We show how these integrals generate a polynomial Poisson algebra. We consider a one-dimensional system with third order ladder operators and found a family of superintegrable systems with higher order integrals of motion. We obtain also the polynomial algebra generated by these integrals. We calculate numerically the trajectories and show that all bounded trajectories are closed.
Second order multidimensional sign-preserving remapping for ALE methods
Hill, Ryan N; Szmelter, J.
2010-12-15
A second-order conservative sign-preserving remapping scheme for Arbitrary Lagrangian-Eulerian (ALE) methods is developed utilising concepts of the Multidimensional Positive Definite Advection Transport Algorithm (MPDATA). The algorithm is inherently multidimensional, and so does not introduce splitting errors. The remapping is implemented in a two-dimensional, finite element ALE solver employing staggered quadrilateral meshes. The MPDATA remapping uses a finite volume discretization developed for volume coordinates. It is applied for the remapping of density and internal energy arranged as cell centered, and velocity as nodal, dependent variables. In the paper, the advection of scalar fields is examined first for test cases with prescribed mesh movement. A direct comparison of MPDATA with the performance of the van Leer MUSCL scheme indicates advantages of a multidimensional approach. Furthermore, distinctly different performance between basic MPDATA and the infinite gauge option is illustrated using benchmarks involving transport of a sign changing velocity field. Further development extends the application of MPDATA remapping to the full ALE solver with a staggered mesh arrangement for density, internal energy and momentum using volume coordinates. At present, two options of the algorithm - basic and infinite gauge - are implemented. To ensure a meaningful assessment, an identical Lagrangian solver and computational mesh update routines are used with either MPDATA or van Leer MUSCL remapping. The evaluation places particular focus on the abilities of both schemes to accurately model multidimensional problems. Theoretical considerations are supported with numerical examples. In addition to the prescribed mesh movement cases for advection of scalars, the demonstrations include two-dimensional Eulerian and ALE flow simulations on quadrilateral meshes with both fixed and variable timestep control. The key comparisons include the standard test cases of Sod and Noh
Generalized compliant motion primitive
NASA Technical Reports Server (NTRS)
Backes, Paul G. (Inventor)
1994-01-01
This invention relates to a general primitive for controlling a telerobot with a set of input parameters. The primitive includes a trajectory generator; a teleoperation sensor; a joint limit generator; a force setpoint generator; a dither function generator, which produces telerobot motion inputs in a common coordinate frame for simultaneous combination in sensor summers. Virtual return spring motion input is provided by a restoration spring subsystem. The novel features of this invention include use of a single general motion primitive at a remote site to permit the shared and supervisory control of the robot manipulator to perform tasks via a remotely transferred input parameter set.
ERIC Educational Resources Information Center
Hawkins, Colleen C.; Watt, Helen M. G.; Sinclair, Kenneth E.
2006-01-01
The psychometric properties of the Frost, Marten, Lahart, and Rosenblate Multidimensional Perfectionism Scale (1990) are investigated to determine its usefulness as a measurement of perfectionism with Australian secondary school girls and to find empirical support for the existence of both healthy and unhealthy types of perfectionist students.…
Projectile Motion with Mathematica.
ERIC Educational Resources Information Center
de Alwis, Tilak
2000-01-01
Describes how to use the computer algebra system (CAS) Mathematica to analyze projectile motion with and without air resistance. These experiments result in several conjectures leading to theorems. (Contains 17 references.) (Author/ASK)
Motional EMF demonstration experiment
NASA Astrophysics Data System (ADS)
Kingman, Robert; Popescu, Sabin
2001-03-01
A simple quantitative motional emf experiment. The induced voltage is recorded in this computer-based experiment as a coil is moved through the field of a permanent magnet. Results compare closely with predicted values.
ERIC Educational Resources Information Center
Grambo, Gregory
1998-01-01
Presents activities on persistence of vision that involve students in a hands-on approach to the study of early methods of creating motion pictures. Students construct flip books, a Zoetrope, and an early movie machine. (DDR)
ERIC Educational Resources Information Center
Lamb, William G.
1985-01-01
Explains a projectile motion experiment involving a bow and arrow. Procedures to measure "muzzle" velocity, bow elastic potential energy, range, flight time, wind resistance, and masses are considered. (DH)
... special tests of eye motion after warm or cold water or air is used to stimulate the ... Get enough fluids Treat infections, including ear infections, colds, flu, sinus congestion, and other respiratory infections If ...
ERIC Educational Resources Information Center
Shourd, Melvin L.
1977-01-01
Describes the construction of an inexpensive apparatus which utilizes the oscillatory motion of 60 cycle AC current in conjunction with an electromagnetic to illustrate various principles and processes in geology. (SL)
ERIC Educational Resources Information Center
Galus, Pamela J.
2002-01-01
Presents a variety of activities that support the development of an understanding of Newton's laws of motion. Activities use toy cars, mobile roads, and a seat-of-nails. Includes a scoring rubric. (DDR)
PROMOTIONS: PROper MOTION Software
NASA Astrophysics Data System (ADS)
Caleb Wherry, John; Sahai, R.
2009-05-01
We report on the development of a software tool (PROMOTIONS) to streamline the process of measuring proper motions of material in expanding nebulae. Our tool makes use of IDL's widget programming capabilities to design a unique GUI that is used to compare images of the objects from two epochs. The software allows us to first orient and register the images to a common frame of reference and pixel scale, using field stars in each of the images. We then cross-correlate specific morphological features in order to determine their proper motions, which consist of the proper motion of the nebula as a whole (PM-neb), and expansion motions of the features relative to the center. If the central star is not visible (quite common in bipolar nebulae with dense dusty waists), point-symmetric expansion is assumed and we use the average motion of high-quality symmetric pairs of features on opposite sides of the nebular center to compute PM-neb. This is then subtracted out to determine the individual movements of these and additional features relative to the nebular center. PROMOTIONS should find wide applicability in measuring proper motions in astrophysical objects such as the expanding outflows/jets commonly seen around young and dying stars. We present first results from using PROMOTIONS to successfully measure proper motions in several pre-planetary nebulae (transition objects between the red giant and planetary nebula phases), using images taken 7-10 years apart with the WFPC2 and ACS instruments on board HST. The authors are grateful to NASA's Undergradute Scholars Research Program (USRP) for supporting this research.
Motion Belts: Visualization of Human Motion Data on a Timeline
NASA Astrophysics Data System (ADS)
Yasuda, Hiroshi; Kaihara, Ryota; Saito, Suguru; Nakajima, Masayuki
Because motion capture system enabled us to capture a number of human motions, the demand for a method to easily browse the captured motion database has been increasing. In this paper, we propose a method to generate simple visual outlines of motion clips, for the purpose of efficient motion data browsing. Our method unfolds a motion clip into a 2D stripe of keyframes along a timeline that is based on semantic keyframe extraction and the best view point selection for each keyframes. With our visualization, timing and order of actions in the motions are clearly visible and the contents of multiple motions are easily comparable. In addition, because our method is applicable for a wide variety of motions, it can generate outlines for a large amount of motions fully automatically.
Incompressible limit of solutions of multidimensional steady compressible Euler equations
NASA Astrophysics Data System (ADS)
Chen, Gui-Qiang G.; Huang, Feimin; Wang, Tian-Yi; Xiang, Wei
2016-06-01
A compactness framework is formulated for the incompressible limit of approximate solutions with weak uniform bounds with respect to the adiabatic exponent for the steady Euler equations for compressible fluids in any dimension. One of our main observations is that the compactness can be achieved by using only natural weak estimates for the mass conservation and the vorticity. Another observation is that the incompressibility of the limit for the homentropic Euler flow is directly from the continuity equation, while the incompressibility of the limit for the full Euler flow is from a combination of all the Euler equations. As direct applications of the compactness framework, we establish two incompressible limit theorems for multidimensional steady Euler flows through infinitely long nozzles, which lead to two new existence theorems for the corresponding problems for multidimensional steady incompressible Euler equations.
A Multidimensional Data Warehouse for Community Health Centers.
Kunjan, Kislaya; Toscos, Tammy; Turkcan, Ayten; Doebbeling, Brad N
2015-01-01
Community health centers (CHCs) play a pivotal role in healthcare delivery to vulnerable populations, but have not yet benefited from a data warehouse that can support improvements in clinical and financial outcomes across the practice. We have developed a multidimensional clinic data warehouse (CDW) by working with 7 CHCs across the state of Indiana and integrating their operational, financial and electronic patient records to support ongoing delivery of care. We describe in detail the rationale for the project, the data architecture employed, the content of the data warehouse, along with a description of the challenges experienced and strategies used in the development of this repository that may help other researchers, managers and leaders in health informatics. The resulting multidimensional data warehouse is highly practical and is designed to provide a foundation for wide-ranging healthcare data analytics over time and across the community health research enterprise.
Advanced numerics for multi-dimensional fluid flow calculations
Vanka, S.P.
1984-04-01
In recent years, there has been a growing interest in the development and use of mathematical models for the simulation of fluid flow, heat transfer and combustion processes in engineering equipment. The equations representing the multi-dimensional transport of mass, momenta and species are numerically solved by finite-difference or finite-element techniques. However despite the multiude of differencing schemes and solution algorithms, and the advancement of computing power, the calculation of multi-dimensional flows, especially three-dimensional flows, remains a mammoth task. The following discussion is concerned with the author's recent work on the construction of accurate discretization schemes for the partial derivatives, and the efficient solution of the set of nonlinear algebraic equations resulting after discretization. The present work has been jointly supported by the Ramjet Engine Division of the Wright Patterson Air Force Base, Ohio, and the NASA Lewis Research Center.
The West Haven-Yale Multidimensional Pain Inventory (WHYMPI).
Kerns, R D; Turk, D C; Rudy, T E
1985-12-01
The complexity of chronic pain has represented a major dilemma for clinical researchers interested in the reliable and valid assessment of the problem and the evaluation of treatment approaches. The West Haven-Yale Multidimensional Pain Inventory (WHYMPI) was developed in order to fill a widely recognized void in the assessment of clinical pain. Assets of the inventory are its brevity and clarity, its foundation in contemporary psychological theory, its multidimensional focus, and its strong psychometric properties. Three parts of the inventory, comprised of 12 scales, examine the impact of pain on the patients' lives, the responses of others to the patients' communications of pain, and the extent to which patients participate in common daily activities. The instrument is recommended for use in conjunction with behavioral and psychophysiological assessment strategies in the evaluation of chronic pain patients in clinical settings. The utility of the WHYMPI in empirical investigations of chronic pain is also discussed.
Multidimensional nanomaterials for the control of stem cell fate
NASA Astrophysics Data System (ADS)
Chueng, Sy-Tsong Dean; Yang, Letao; Zhang, Yixiao; Lee, Ki-Bum
2016-09-01
Current stem cell therapy suffers low efficiency in giving rise to differentiated cell lineages, which can replace the original damaged cells. Nanomaterials, on the other hand, provide unique physical size, surface chemistry, conductivity, and topographical microenvironment to regulate stem cell differentiation through multidimensional approaches to facilitate gene delivery, cell-cell, and cell-ECM interactions. In this review, nanomaterials are demonstrated to work both alone and synergistically to guide selective stem cell differentiation. From three different nanotechnology families, three approaches are shown: (1) soluble microenvironmental factors; (2) insoluble physical microenvironment; and (3) nano-topographical features. As regenerative medicine is heavily invested in effective stem cell therapy, this review is inspired to generate discussions in the potential clinical applications of multi-dimensional nanomaterials.
Optimized Linear Prediction for Radial Sampled Multidimensional NMR Experiments
Gledhill, John M.; Kasinath, Vignesh; Wand, A. Joshua
2011-01-01
Radial sampling in multidimensional NMR experiments offers greatly decreased acquisition times while also providing an avenue for increased sensitivity. Digital resolution remains concern and depends strongly upon the extent of sampling of individual radial angles. Truncated time domain data leads to spurious peaks (artifacts) upon FT and 2D FT. Linear prediction is commonly employed to improve resolution in Cartesian sampled NMR experiments. Here, we adapt the linear prediction method to radial sampling. Significantly more accurate estimates of linear prediction coefficients are obtained by combining quadrature frequency components from the multiple angle spectra. This approach results in significant improvement in both resolution and removal of spurious peaks as compared to traditional linear prediction methods applied to radial sampled data. The ‘averaging linear prediction’ (ALP) method is demonstrated as a general tool for resolution improvement in multidimensional radial sampled experiments. PMID:21767968
Advanced numerics for multi-dimensional fluid flow calculations
NASA Technical Reports Server (NTRS)
Vanka, S. P.
1984-01-01
In recent years, there has been a growing interest in the development and use of mathematical models for the simulation of fluid flow, heat transfer and combustion processes in engineering equipment. The equations representing the multi-dimensional transport of mass, momenta and species are numerically solved by finite-difference or finite-element techniques. However despite the multiude of differencing schemes and solution algorithms, and the advancement of computing power, the calculation of multi-dimensional flows, especially three-dimensional flows, remains a mammoth task. The following discussion is concerned with the author's recent work on the construction of accurate discretization schemes for the partial derivatives, and the efficient solution of the set of nonlinear algebraic equations resulting after discretization. The present work has been jointly supported by the Ramjet Engine Division of the Wright Patterson Air Force Base, Ohio, and the NASA Lewis Research Center.
Fitness of multidimensional phenotypes in dynamic adaptive landscapes.
Laughlin, Daniel C; Messier, Julie
2015-08-01
Phenotypic traits influence species distributions, but ecology lacks established links between multidimensional phenotypes and fitness for predicting species responses to environmental change. The common focus on single traits rather than multiple trait combinations limits our understanding of their adaptive value, and intraspecific trait covariation has been neglected in ecology despite its importance in evolutionary theory and its likely impact on species distributions. Here, we extend the adaptive landscape framework to ecological sorting of multidimensional phenotypes across environments and discuss how two analytical approaches can be used to quantify fitness as a function of the interaction between the phenotype and the environment. We encourage ecologists to consider how phenotypic integration will constrain species responses to environmental change.
Analyzing stochastic dependence of cognitive processes in multidimensional source recognition.
Meiser, Thorsten
2014-01-01
Stochastic dependence among cognitive processes can be modeled in different ways, and the family of multinomial processing tree models provides a flexible framework for analyzing stochastic dependence among discrete cognitive states. This article presents a multinomial model of multidimensional source recognition that specifies stochastic dependence by a parameter for the joint retrieval of multiple source attributes together with parameters for stochastically independent retrieval. The new model is equivalent to a previous multinomial model of multidimensional source memory for a subset of the parameter space. An empirical application illustrates the advantages of the new multinomial model of joint source recognition. The new model allows for a direct comparison of joint source retrieval across conditions, it avoids statistical problems due to inflated confidence intervals and does not imply a conceptual imbalance between source dimensions. Model selection criteria that take model complexity into account corroborate the new model of joint source recognition.
Multidimensional profiles of health locus of control in Hispanic Americans.
Champagne, Brian R; Fox, Rina S; Mills, Sarah D; Sadler, Georgia Robins; Malcarne, Vanessa L
2016-10-01
Latent profile analysis identified health locus of control profiles among 436 Hispanic Americans who completed the Multidimensional Health Locus of Control scales. Results revealed four profiles: Internally Oriented-Weak, -Moderate, -Strong, and Externally Oriented. The profile groups were compared on sociocultural and demographic characteristics, health beliefs and behaviors, and physical and mental health outcomes. The Internally Oriented-Strong group had less cancer fatalism, religiosity, and equity health attributions, and more alcohol consumption than the other three groups; the Externally Oriented group had stronger equity health attributions and less alcohol consumption. Deriving multidimensional health locus of control profiles through latent profile analysis allows examination of the relationships of health locus of control subtypes to health variables.
Coherent multidimensional optical spectra measured using incoherent light
NASA Astrophysics Data System (ADS)
Turner, Daniel B.; Arpin, Paul C.; McClure, Scott D.; Ulness, Darin J.; Scholes, Gregory D.
2013-08-01
Four-wave mixing measurements can reveal spectral and dynamics information that is hidden in linear spectra by the interactions among light-absorbing molecules and with their environment. Coherent multidimensional optical spectroscopy is an important variant of four-wave mixing because it resolves a map of interactions and correlations between absorption bands. Previous coherent multidimensional optical spectroscopy measurements have used femtosecond pulses with great success, and it may seem that femtosecond pulses are necessary for such measurements. Here we present coherent two-dimensional electronic spectra measured using incoherent light. The spectra of model molecular systems using broadband spectrally incoherent light are similar but not identical to those expected from measurements using femtosecond pulses. Specifically, the spectra show particular sensitivity to long-lived intermediates such as photoisomers. The results will motivate the design of similar experiments in spectral ranges where femtosecond pulses are difficult to produce.
Multidimensional Analysis of Quenching: Comparison of Inverse Techniques
Dowding, K.J.
1998-11-18
Understanding the surface heat transfer during quenching can be beneficial. Analysis to estimate the surface heat transfer from internal temperature measurements is referred to as the inverse heat conduction problem (IHCP). Function specification and gradient adjoint methods, which use a gradient search method coupled with an adjoint operator, are widely u led methods to solve the IHCP. In this paper the two methods are presented for the multidimensional case. The focus is not a rigorous comparison of numerical results. Instead after formulating the multidimensional solutions, issues associated with the numerical implementation and practical application of the methods are discussed. In addition, an experiment that measured the surface heat flux and temperatures for a transient experimental case is analyzed. Transient temperatures are used to estimate the surface heat flux, which is compared to the measured values. The estimated surface fluxes are comparable for the two methods.
An object-oriented multidimensional model for data warehouse
NASA Astrophysics Data System (ADS)
Gosain, Anjana; Mann, Suman
2011-12-01
Organizations, to have a competitive edge upon each other, resort to business intelligence which refers to information available for enterprise to make strategic decisions. Data warehouse being the repository of data provides the backend for achieving business intelligence. The design of data warehouse, thereby, forms the key, to extract and obtain the relevant information facilitating to make strategic decisions. The initial focus for the design had been upon the conceptual models but now object oriented multidimensional modelling has emerged as the foundation for the designing of data warehouse. Several proposals have been put forth for object oriented multidimensional modelling, each incorporating some or other features, but not all. This paper consolidates all the features previously introduced and the new introduced, thus, proposing a new model having features to be incorporated while designing the data warehouse.
Multidimensional and Multimodal Separations by HPTLC in Phytochemistry
NASA Astrophysics Data System (ADS)
Ciesla, Lukasz; Waksmundzka-Hajnos, Monika
HPTLC is one of the most widely applied methods in phytochemical analysis. It is due to its numerous advantages, e.g., it is the only chromatographic method offering the option of presenting the results as an image. Other advantages include simplicity, low costs, parallel analysis of samples, high sample capacity, rapidly obtained results, and possibility of multiple detection. HPTLC provides identification as well as quantitative results. It also enables the identification of adulterants. In case of complex samples, the resolving power of traditional one-dimensional chromatography is usually inadequate, hence special modes of development are required. Multidimensional and multimodal HPTLC techniques include those realized in one direction (UMD, IMD, GMD, BMD, AMD) as well as typical two-dimensional methods realized on mono- or bi-layers. In this manuscript, an overview on variable multidimensional and multimodal methods, applied in the analysis of phytochemical samples, is presented.
Counting multidimensional objects: implications for the neural-synchrony theory.
Goldfarb, Liat; Treisman, Anne
2013-03-01
It has been suggested that a neural instantiation of the temporary multidimensional representations of objects might be synchrony of firing between the neurons representing the features that co-occur in a given location. In this article, we direct attention to a logical problem that arises when certain synchrony assumptions are applied to real situations in which multiple multidimensional objects are presented. We demonstrate a new behavioral effect that shows that this logical problem coincides with a genuine behavioral problem. Even when a display contains only a small number of objects characterized by features on two dimensions, the representation of the display becomes difficult when, according to our described assumptions, the object representations cannot be simultaneously synchronized on both features. This article outlines a new principle that governs object representation, and the experimental results might be unique behavioral evidence for a neural-based theory of feature binding. PMID:23334446
A Multidimensional Data Warehouse for Community Health Centers
Kunjan, Kislaya; Toscos, Tammy; Turkcan, Ayten; Doebbeling, Brad N.
2015-01-01
Community health centers (CHCs) play a pivotal role in healthcare delivery to vulnerable populations, but have not yet benefited from a data warehouse that can support improvements in clinical and financial outcomes across the practice. We have developed a multidimensional clinic data warehouse (CDW) by working with 7 CHCs across the state of Indiana and integrating their operational, financial and electronic patient records to support ongoing delivery of care. We describe in detail the rationale for the project, the data architecture employed, the content of the data warehouse, along with a description of the challenges experienced and strategies used in the development of this repository that may help other researchers, managers and leaders in health informatics. The resulting multidimensional data warehouse is highly practical and is designed to provide a foundation for wide-ranging healthcare data analytics over time and across the community health research enterprise. PMID:26958297
Geologically current plate motions
NASA Astrophysics Data System (ADS)
DeMets, Charles; Gordon, Richard G.; Argus, Donald F.
2010-04-01
We describe best-fitting angular velocities and MORVEL, a new closure-enforced set of angular velocities for the geologically current motions of 25 tectonic plates that collectively occupy 97 per cent of Earth's surface. Seafloor spreading rates and fault azimuths are used to determine the motions of 19 plates bordered by mid-ocean ridges, including all the major plates. Six smaller plates with little or no connection to the mid-ocean ridges are linked to MORVEL with GPS station velocities and azimuthal data. By design, almost no kinematic information is exchanged between the geologically determined and geodetically constrained subsets of the global circuit-MORVEL thus averages motion over geological intervals for all the major plates. Plate geometry changes relative to NUVEL-1A include the incorporation of Nubia, Lwandle and Somalia plates for the former Africa plate, Capricorn, Australia and Macquarie plates for the former Australia plate, and Sur and South America plates for the former South America plate. MORVEL also includes Amur, Philippine Sea, Sundaland and Yangtze plates, making it more useful than NUVEL-1A for studies of deformation in Asia and the western Pacific. Seafloor spreading rates are estimated over the past 0.78 Myr for intermediate and fast spreading centres and since 3.16 Ma for slow and ultraslow spreading centres. Rates are adjusted downward by 0.6-2.6mmyr-1 to compensate for the several kilometre width of magnetic reversal zones. Nearly all the NUVEL-1A angular velocities differ significantly from the MORVEL angular velocities. The many new data, revised plate geometries, and correction for outward displacement thus significantly modify our knowledge of geologically current plate motions. MORVEL indicates significantly slower 0.78-Myr-average motion across the Nazca-Antarctic and Nazca-Pacific boundaries than does NUVEL-1A, consistent with a progressive slowdown in the eastward component of Nazca plate motion since 3.16 Ma. It also
NASA Technical Reports Server (NTRS)
Homick, J. L.
1979-01-01
Research on the etiology, prediction, treatment and prevention of space motion sickness, designed to minimize the impact of this syndrome which was experienced frequently and with severity by individuals on the Skylab missions, on Space Shuttle crews is reviewed. Theories of the cause of space motion sickness currently under investigation by NASA include sensory conflict, which argues that motion sickness symptoms result from a mismatch between the total pattern of information from the spatial senses and that stored from previous experiences, and fluid shift, based upon the redistribution of bodily fluids that occurs upon continued exposure to weightlessness. Attempts are underway to correlate space motion sickness susceptibility to different provocative environments, vestibular and nonvestibular responses, and the rate of acquisition and length of retention of sensory adaptation. Space motion sickness countermeasures under investigation include various drug combinations, of which the equal combination of promethazine and ephedrine has been found to be as effective as the scopolomine and dexedrine combination, and vestibular adaptation and biofeedback training and autogenic therapy.
ERIC Educational Resources Information Center
Demana, Franklin; Waits, Bert K.
1993-01-01
Discusses solutions to real-world linear particle-motion problems using graphing calculators to simulate the motion and traditional analytic methods of calculus. Applications include (1) changing circular or curvilinear motion into linear motion and (2) linear particle accelerators in physics. (MDH)
Analysis of self-similar solutions of multidimensional conservation laws
Keyfitz, Barbara
2014-02-15
This project focused on analysis of multidimensional conservation laws, specifically on extensions to the study of self-siminar solutions, a project initiated by the PI. In addition, progress was made on an approach to studying conservation laws of very low regularity; in this research, the context was a novel problem in chromatography. Two graduate students in mathematics were supported during the grant period, and have almost completed their thesis research.
Probes for multidimensional nanospectroscopic imaging and methods of fabrication thereof
Weber-Bargioni, Alexander; Cabrini, Stefano; Bao, Wei; Melli, Mauro; Yablonovitch, Eli; Schuck, Peter J
2015-03-17
This disclosure provides systems, methods, and apparatus related to probes for multidimensional nanospectroscopic imaging. In one aspect, a method includes providing a transparent tip comprising a dielectric material. A four-sided pyramidal-shaped structure is formed at an apex of the transparent tip using a focused ion beam. Metal layers are deposited over two opposing sides of the four-sided pyramidal-shaped structure.
Unveiling Bacterial Interactions through Multidimensional Scaling and Dynamics Modeling
Dorado-Morales, Pedro; Vilanova, Cristina; P. Garay, Carlos; Martí, Jose Manuel; Porcar, Manuel
2015-01-01
We propose a new strategy to identify and visualize bacterial consortia by conducting replicated culturing of environmental samples coupled with high-throughput sequencing and multidimensional scaling analysis, followed by identification of bacteria-bacteria correlations and interactions. We conducted a proof of concept assay with pine-tree resin-based media in ten replicates, which allowed detecting and visualizing dynamical bacterial associations in the form of statistically significant and yet biologically relevant bacterial consortia. PMID:26671778
Multidimensional signal modulation and/or demodulation for data communications
Smith, Stephen F.; Dress, William B.
2008-03-04
Systems and methods are described for multidimensional signal modulation and/or demodulation for data communications. A method includes modulating a carrier signal in a first domain selected from the group consisting of phase, frequency, amplitude, polarization and spread; modulating the carrier signal in a second domain selected from the group consisting of phase, frequency, amplitude, polarization and spread; and modulating the carrier signal in a third domain selected from the group consisting of phase, frequency, amplitude, polarization and spread.
Application of Multidimensional Spectrum Analysis for Analytical Chemistry
Hatsukawa, Yuichi; Hayakawa, Takehito; Toh, Yosuke; Shinohara, Nobuo; Oshima, Masumi
1999-12-31
Feasibility of application of the multidimensional {gamma} ray spectroscopy for analytical chemistry was examined. Two reference igneous rock (JP-1, JB-1a) samples issued by the Geological Survey of Japan (GSJ) were irradiated at a research reactor with thermal neutrons, and {gamma} rays from the radioisotopes produced by neutron capture reactions were measured using a {gamma}-ray detector array. Simultaneously 27 elements were observed with no chemical separation.
Multidimensional, multiphysics simulations of core-collapse supernovae
Messer, Bronson; Mezzacappa, Anthony; Blondin, J. M.; Bruenn, S. W.; Hix, William Raphael
2008-01-01
CHIMERA is a multi-dimensional radiation hydrodynamics code designed to study core-collapse supernovae. The code is made up of three essentially independent parts: a hydrodynamics module, a nuclear burning module, and a neutrino transport solver combined within an operator-split approach. We review the code s architecture and some recently improved implementations used in the code. We also briefly discuss preliminary results obtained with the code in three spatial dimensions.
Multidimensional, multiphysics simulations of core-collapse supernovae
Messer, Bronson; Mezzacappa, Anthony; Blondin, J. M.; Bruenn, S. W.; Hix, William Raphael
2008-01-01
CHIMERA is a multi-dimensional radiation hydrodynamics code designed to study core-collapse supernovae. The code is made up of three essentially independent parts: a hydrodynamics module, a nuclear burning module, and a neutrino transport solver combined within an operator-split approach. We review the code's architecture and some recently improved implementations used in the code. We also briefly discuss preliminary results obtained with the code in three spatial dimensions.
Multidimensionality in host manipulation mimicked by serotonin injection.
Perrot-Minnot, Marie-Jeanne; Sanchez-Thirion, Kevin; Cézilly, Frank
2014-12-01
Manipulative parasites often alter the phenotype of their hosts along multiple dimensions. 'Multidimensionality' in host manipulation could consist in the simultaneous alteration of several physiological pathways independently of one another, or proceed from the disruption of some key physiological parameter, followed by a cascade of effects. We compared multidimensionality in 'host manipulation' between two closely related amphipods, Gammarus fossarum and Gammarus pulex, naturally and experimentally infected with Pomphorhynchus laevis (Acanthocephala), respectively. To that end, we calculated in each host-parasite association the effect size of the difference between infected and uninfected individuals for six different traits (activity, phototaxis, geotaxis, attraction to conspecifics, refuge use and metabolic rate). The effects sizes were highly correlated between host-parasite associations, providing evidence for a relatively constant 'infection syndrome'. Using the same methodology, we compared the extent of phenotypic alterations induced by an experimental injection of serotonin (5-HT) in uninfected G. pulex to that induced by experimental or natural infection with P. laevis. We observed a significant correlation between effect sizes across the six traits, indicating that injection with 5-HT can faithfully mimic the 'infection syndrome'. This is, to our knowledge, the first experimental evidence that multidimensionality in host manipulation can proceed, at least partly, from the disruption of some major physiological mechanism.
Multidimensional colorimetric sensor array for discrimination of proteins.
Mao, Jinpeng; Lu, Yuexiang; Chang, Ning; Yang, Jiaoe; Zhang, Sichun; Liu, Yueying
2016-12-15
An extensible multidimensional colorimetric sensor array for the detection of protein is developed based on DNA functionalized gold nanoparticles (DNA-AuNPs) as receptors. In the presence of different proteins, the aggregation behavior of DNA-AuNPs was regulated by the high concentrations of salt and caused different color change; while DNA-AuNPs grew induced by the reduction of HAuCl4 and NH2OH as a reductant on the surface of nanoparticles exhibited different morphologies and color appearance for different proteins. The transducers based on AuNPs modified by specific and nonspecific DNA enables naked-eye discrimination of the target analytes. This extensible sensing platform with only two receptors could simultaneously discriminate ten native proteins and their thermally denatured conformations using hierarchical cluster analysis (HCA) at the concentration of 50nM with 100% accuracy. This opens up the possibility of the sensor array to investigate the different conformational changes of biomacromolecules, and it gives a new direction of developing multidimensional transduction principles based on plasmonic nanoparticle conjugates. Furthermore, the sensing system could discriminate proteins at the concentration of 500nM in the presence of 50% human urine, which indicated this sensor array has great potential ability in analyzing real biological fluids. In addition, the multidimensional colorimetric sensor array is suitable for analysis of target analytes in the resource-restricted regions because of rapid, simple, low cost, and in-field detection with the naked eye. PMID:27322936
Multidimensionality in host manipulation mimicked by serotonin injection.
Perrot-Minnot, Marie-Jeanne; Sanchez-Thirion, Kevin; Cézilly, Frank
2014-12-01
Manipulative parasites often alter the phenotype of their hosts along multiple dimensions. 'Multidimensionality' in host manipulation could consist in the simultaneous alteration of several physiological pathways independently of one another, or proceed from the disruption of some key physiological parameter, followed by a cascade of effects. We compared multidimensionality in 'host manipulation' between two closely related amphipods, Gammarus fossarum and Gammarus pulex, naturally and experimentally infected with Pomphorhynchus laevis (Acanthocephala), respectively. To that end, we calculated in each host-parasite association the effect size of the difference between infected and uninfected individuals for six different traits (activity, phototaxis, geotaxis, attraction to conspecifics, refuge use and metabolic rate). The effects sizes were highly correlated between host-parasite associations, providing evidence for a relatively constant 'infection syndrome'. Using the same methodology, we compared the extent of phenotypic alterations induced by an experimental injection of serotonin (5-HT) in uninfected G. pulex to that induced by experimental or natural infection with P. laevis. We observed a significant correlation between effect sizes across the six traits, indicating that injection with 5-HT can faithfully mimic the 'infection syndrome'. This is, to our knowledge, the first experimental evidence that multidimensionality in host manipulation can proceed, at least partly, from the disruption of some major physiological mechanism. PMID:25339729
Interdisciplinary hospice team processes and multidimensional pain: a qualitative study.
Dugan Day, Michele
2012-01-01
Hospice teams may address multidimensional pain through the synergistic interaction of team members from various professional disciplines during regularly scheduled team meetings. However, the occurrence of that critical exchange has not been adequately described or documented. The purpose of this qualitative study was to explore two processes in team pain palliation: communication and collaboration. Data were gathered through individual interviews and a 1-year observation of team members from two hospices (physicians, nurses, aides, chaplains, social workers). Utilizing constant comparison, 14 final thematic categories were discovered. Use of biopsychosocial/spiritual terms by all team members meant that the team had the common language needed to communicate about multidimensional pain. Interviews and observation revealed a gap in translating multidisciplinary communication in team meetings into collaborative acts for pain treatment. In addition, structural influences inhibited creativity in pain palliation. There was no mutual understanding of the purpose for team meetings, no recognition of the need to reflect on team process, or common definition of leadership. Social work roles in hospice should include leadership that moves teams toward interdisciplinary care for multidimensional pain.
Multidimensional EEMD filter bank for geophysical data processing
NASA Astrophysics Data System (ADS)
Jeng, Yih; Chen, Chih-Sung; Lee, Chao-Shing
2014-05-01
The ensemble empirical mode decomposition (EEMD) algorithm is a noise-assisted data-driven nonlinear analysis method evolved from its original version, the empirical mode decomposition (EMD) method. The advantage of using EEMD is mainly to alleviate mode mixing problem of the EMD filter bank. The EMD and EEMD techniques have been widely applied to many fields of scientific and engineering studies in the last decade but just a few to the geophysical exploration data analysis probably due to the multidimensional feature of exploration data. Several 2D EMD based data analysis algorithms have been developed lately; however, the difficulty of sifting 2D data and the mode mixing problem inherited from EMD algorithm hindered their further developments. To deal with the stated issues, we modify a newer technique, the multidimensional ensemble empirical mode decomposition (MDEEMD) algorithm, to achieve a 2D EEMD filter bank for exploration data signal enhancement. With the data reconstructed by using significant components of the filter bank, the signal embedded in the original data can be retrieved successfully. Furthermore, we compare the performance of MDEEMD with that of logarithmic transformed multidimensional empirical mode decomposition (NLT MDEMD) to find a solution for compromising computation cost. A controlled model study along with a set of real exploration data example are provided to demonstrate the robustness of the proposed method.
An Improved Multidimensional MPA Procedure for Bidirectional Earthquake Excitations
Wang, Feng; Sun, Jian-Gang; Zhang, Ning
2014-01-01
Presently, the modal pushover analysis procedure is extended to multidimensional analysis of structures subjected to multidimensional earthquake excitations. an improved multidimensional modal pushover analysis (IMMPA) method is presented in the paper in order to estimate the response demands of structures subjected to bidirectional earthquake excitations, in which the unidirectional earthquake excitation applied on equivalent SDOF system is replaced by the direct superposition of two components earthquake excitations, and independent analysis in each direction is not required and the application of simplified superposition formulas is avoided. The strength reduction factor spectra based on superposition of earthquake excitations are discussed and compared with the traditional strength reduction factor spectra. The step-by-step procedure is proposed to estimate seismic demands of structures. Two examples are implemented to verify the accuracy of the method, and the results of the examples show that (1) the IMMPA method can be used to estimate the responses of structure subjected to bidirectional earthquake excitations. (2) Along with increase of peak of earthquake acceleration, structural response deviation estimated with the IMMPA method may also increase. (3) Along with increase of the number of total floors of structures, structural response deviation estimated with the IMMPA method may also increase. PMID:25140333
An improved multidimensional MPA procedure for bidirectional earthquake excitations.
Wang, Feng; Sun, Jian-Gang; Zhang, Ning
2014-01-01
Presently, the modal pushover analysis procedure is extended to multidimensional analysis of structures subjected to multidimensional earthquake excitations. an improved multidimensional modal pushover analysis (IMMPA) method is presented in the paper in order to estimate the response demands of structures subjected to bidirectional earthquake excitations, in which the unidirectional earthquake excitation applied on equivalent SDOF system is replaced by the direct superposition of two components earthquake excitations, and independent analysis in each direction is not required and the application of simplified superposition formulas is avoided. The strength reduction factor spectra based on superposition of earthquake excitations are discussed and compared with the traditional strength reduction factor spectra. The step-by-step procedure is proposed to estimate seismic demands of structures. Two examples are implemented to verify the accuracy of the method, and the results of the examples show that (1) the IMMPA method can be used to estimate the responses of structure subjected to bidirectional earthquake excitations. (2) Along with increase of peak of earthquake acceleration, structural response deviation estimated with the IMMPA method may also increase. (3) Along with increase of the number of total floors of structures, structural response deviation estimated with the IMMPA method may also increase. PMID:25140333
Igloo-Plot: a tool for visualization of multidimensional datasets.
Kuntal, Bhusan K; Ghosh, Tarini Shankar; Mande, Sharmila S
2014-01-01
Advances in science and technology have resulted in an exponential growth of multivariate (or multi-dimensional) datasets which are being generated from various research areas especially in the domain of biological sciences. Visualization and analysis of such data (with the objective of uncovering the hidden patterns therein) is an important and challenging task. We present a tool, called Igloo-Plot, for efficient visualization of multidimensional datasets. The tool addresses some of the key limitations of contemporary multivariate visualization and analysis tools. The visualization layout, not only facilitates an easy identification of clusters of data-points having similar feature compositions, but also the 'marker features' specific to each of these clusters. The applicability of the various functionalities implemented herein is demonstrated using several well studied multi-dimensional datasets. Igloo-Plot is expected to be a valuable resource for researchers working in multivariate data mining studies. Igloo-Plot is available for download from: http://metagenomics.atc.tcs.com/IglooPlot/.
Theme section: Multi-dimensional modelling, analysis and visualization
NASA Astrophysics Data System (ADS)
Guilbert, Éric; Çöltekin, Arzu; Castro, Francesc Antón; Pettit, Chris
2016-07-01
Spatial data are now collected and processed in larger amounts, and used by larger populations than ever before. While most geospatial data have traditionally been recorded as two-dimensional data, the evolution of data collection methods and user demands have led to data beyond the two dimensions describing complex multidimensional phenomena. An example of the relevance of multidimensional modelling is seen with the development of urban modelling where several dimensions have been added to the traditional 2D map representation (Sester et al., 2011). These include obviously the third spatial dimension (Biljecki et al., 2015) as well as the temporal, but also the scale dimension (Van Oosterom and Stoter, 2010) or, as mentioned by (Lu et al., 2016), multi-spectral and multi-sensor data. Such a view provides an organisation of multidimensional data around these different axes and it is time to explore each axis as the availability of unprecedented amounts of new data demands new solutions. The availability of such large amounts of data induces an acute need for developing new approaches to assist with their dissemination, visualisation, and analysis by end users. Several issues need to be considered in order to provide a meaningful representation and assist in data visualisation and mining, modelling and analysis; such as data structures allowing representation at different scales or in different contexts of thematic information.
Maragó, Onofrio M; Bonaccorso, Francesco; Saija, Rosalba; Privitera, Giulia; Gucciardi, Pietro G; Iatì, Maria Antonia; Calogero, Giuseppe; Jones, Philip H; Borghese, Ferdinando; Denti, Paolo; Nicolosi, Valeria; Ferrari, Andrea C
2010-12-28
Brownian motion is a manifestation of the fluctuation-dissipation theorem of statistical mechanics. It regulates systems in physics, biology, chemistry, and finance. We use graphene as prototype material to unravel the consequences of the fluctuation-dissipation theorem in two dimensions, by studying the Brownian motion of optically trapped graphene flakes. These orient orthogonal to the light polarization, due to the optical constants anisotropy. We explain the flake dynamics in the optical trap and measure force and torque constants from the correlation functions of the tracking signals, as well as comparing experiments with a full electromagnetic theory of optical trapping. The understanding of optical trapping of two-dimensional nanostructures gained through our Brownian motion analysis paves the way to light-controlled manipulation and all-optical sorting of biological membranes and anisotropic macromolecules. PMID:21133432
Unruh, W.P.
1987-03-23
Method and apparatus are provided for deriving positive and negative Doppler spectrum to enable analysis of objects in motion, and particularly, objects having rotary motion. First and second returned radar signals are mixed with internal signals to obtain an in-phase process signal and a quadrature process signal. A broad-band phase shifter shifts the quadrature signal through 90/degree/ relative to the in-phase signal over a predetermined frequency range. A pair of signals is output from the broad-band phase shifter which are then combined to provide a first side band signal which is functionally related to a negative Doppler shift spectrum. The distinct positive and negative Doppler spectra may then be analyzed for the motion characteristics of the object being examined.
Intrinsic Feature Motion Tracking
Goddard, Jr., James S.
2013-03-19
Subject motion during 3D medical scanning can cause blurring and artifacts in the 3D images resulting in either rescans or poor diagnosis. Anesthesia or physical restraints may be used to eliminate motion but are undesirable and can affect results. This software measures the six degree of freedom 3D motion of the subject during the scan under a rigidity assumption using only the intrinsic features present on the subject area being monitored. This movement over time can then be used to correct the scan data removing the blur and artifacts. The software acquires images from external cameras or images stored on disk for processing. The images are from two or three calibrated cameras in a stereo arrangement. Algorithms extract and track the features over time and calculate position and orientation changes relative to an initial position. Output is the 3D position and orientation change measured at each image.
Intrinsic Feature Motion Tracking
2013-03-19
Subject motion during 3D medical scanning can cause blurring and artifacts in the 3D images resulting in either rescans or poor diagnosis. Anesthesia or physical restraints may be used to eliminate motion but are undesirable and can affect results. This software measures the six degree of freedom 3D motion of the subject during the scan under a rigidity assumption using only the intrinsic features present on the subject area being monitored. This movement over timemore » can then be used to correct the scan data removing the blur and artifacts. The software acquires images from external cameras or images stored on disk for processing. The images are from two or three calibrated cameras in a stereo arrangement. Algorithms extract and track the features over time and calculate position and orientation changes relative to an initial position. Output is the 3D position and orientation change measured at each image.« less
NASA Technical Reports Server (NTRS)
Mcclure, P.
1973-01-01
An analytical theory is developed to describe diurnal polar motion in the earth which arises as a forced response due to lunisolar torques and tidal deformation. Doodson's expansion of the tide generating potential is used to represent the lunisolar torques. Both the magnitudes and the rates of change of perturbations in the earth's inertia tensor are included in the dynamical equations for the polar motion so as to account for rotational and tidal deformation. It is found that in a deformable earth with Love's number k = 0.29, the angular momentum vector departs by as much as 20 cm from the rotation axis rather than remaining within 1 or 2 cm as it would in a rigid earth. This 20 cm separation is significant in the interpretation of submeter polar motion observations because it necessitates an additional coordinate transformation in order to remove what would otherwise be a 20 cm error source in the conversion between inertial and terrestrial reference systems.
Muscle Motion Solenoid Actuator
NASA Astrophysics Data System (ADS)
Obata, Shuji
It is one of our dreams to mechanically recover the lost body for damaged humans. Realistic humanoid robots composed of such machines require muscle motion actuators controlled by all pulling actions. Particularly, antagonistic pairs of bi-articular muscles are very important in animal's motions. A system of actuators is proposed using the electromagnetic force of the solenoids with the abilities of the stroke length over 10 cm and the strength about 20 N, which are needed to move the real human arm. The devised actuators are based on developments of recent modern electro-magnetic materials, where old time materials can not give such possibility. Composite actuators are controlled by a high ability computer and software making genuine motions.
NASA Technical Reports Server (NTRS)
Gallenstein, J.; Huston, R. L.
1973-01-01
This paper presents an analysis of swimming motion with specific attention given to the flutter kick, the breast-stroke kick, and the breast stroke. The analysis is completely theoretical. It employs a mathematical model of the human body consisting of frustrums of elliptical cones. Dynamical equations are written for this model including both viscous and inertia forces. These equations are then applied with approximated swimming strokes and solved numerically using a digital computer. The procedure is to specify the input of the swimming motion. The computer solution then provides the output displacement, velocity, and rotation or body roll of the swimmer.
Dembo, M.
1986-01-01
The reactive flow model is a putative description of amoeboid cytoplasm based on the formalism of multifield fluid mechanics. We show by direct numerical computations that the reactive flow model is able to account for various phenomena observed in dissociated cytoplasm and/or in vitro contractile networks. These phenomena include states of relaxation or mechanical equilibrium, as well as transitions between such states, by processes of expansion or contraction. Simulations also indicate the existence of states of chaotic or turbulent cytoplasmic streaming. Finally, simulations yield steady states of coherent motion similar to motions observed in cytoplasm dissociated from the giant amoeba, Chaos carolinensis.
Dislocation motion and instability
NASA Astrophysics Data System (ADS)
Zhu, Yichao; Chapman, Stephen Jonathan; Acharya, Amit
2013-08-01
The Peach-Koehler expression for the stress generated by a single (non-planar) curvilinear dislocation is evaluated to calculate the dislocation self stress. This is combined with a law of motion to give the self-induced motion of a general dislocation curve. A stability analysis of a rectilinear, uniformly translating dislocation is then performed. The dislocation is found to be susceptible to a helical instability, with the maximum growth rate occurring when the dislocation is almost, but not exactly, pure screw. The non-linear evolution of the instability is determined numerically, and implications for slip band formation and non-Schmid behavior in yielding are discussed.
Samady, Waheeda; Sadler, Georgia Robins; Nakaji, Melanie; Malcarne, Vanessa L.; Trybus, Raymond; Athale, Ninad
2008-01-01
This paper describes the translation of the Multidimensional Health Locus of Control (MHLC) scales into American Sign Language (ASL). Translation is an essential first step toward validating the instrument for use in the Deaf community, a commonly overlooked minority community. This translated MHLC/ASL can be utilized by public health nurses researching the Deaf community to create and evaluate targeted health interventions. It can be used in clinical settings to guide the context of the provider-patient dialogue. The MHLC was translated using focus groups, following recommended procedures. Five bilingual participants translated the MHLC into ASL; five others back-translated the ASL version into English. Both focus groups identified and addressed language and cultural problems before the final ASL version of the MHLC was permanently captured on by motion picture photography for consistent administration. Nine of the 24 items were directly translatable into ASL. The remaining items required further discussion to achieve cultural equivalence with ASL expressions. The MHLC/ASL is now ready for validation within the Deaf community. PMID:18816365
Numerical modeling of multidimensional flow in seals and bearings used in rotating machinery
NASA Technical Reports Server (NTRS)
Hendricks, R. C.; Tam, L. T.; Przekwas, A.; Muszynska, A.; Braun, M. J.; Mullen, R. L.
1988-01-01
The rotordynamic behavior of turbomachinery is critically dependent on fluid dynamic rotor forces developed by various types of seals and bearings. The occurrence of self-excited vibrations often depends on the rotor speed and load. Misalignment and rotor wobbling motion associated with differential clearance were often attributed to stability problems. In general, the rotative character of the flowfield is a complex three dimensional system with secondary flow patterns that significantly alter the average fluid circumferential velocity. A multidimensional, nonorthogonal, body-fitted-grid fluid flow model is presented that describes the fluid dynamic forces and the secondary flow pattern development in seals and bearings. Several numerical experiments were carried out to demonstrate the characteristics of this complex flowfield. Analyses were performed by solving a conservation form of the three dimensional Navier-Stokes equations transformed to those for a rotating observer and using the general-purpose computer code PHOENICS with the assumptions that the rotor orbit is circular and that static eccentricity is zero. These assumptions have enabled a precise steady-state analysis to be used. Fluid injection from ports near the seal or bearing center increased fluid-film direct dynamic stiffness and, in some cases, significantly increased quadrature dynamic stiffness. Injection angle and velocity could be used for active rotordynamic control; for example, injection, when compared with no injection, increased direct dynamic stiffness, which is an important factor for hydrostatic bearings.
Pashupati Dhakal, Harukazu Yoshino, Jeong-Il Oh, Koichi Kikuchi, Michael J. Naughton
2012-09-01
Angle-dependent magnetoresistance experiments on organic conductors exhibit a wide range of angular oscillations associated with the dimensionality and symmetry of the crystal structure and electron energy dispersion. In particular, characteristics associated with 1, 2, and 3-dimensional electronic motion are separately revealed when a sample is rotated through different crystal planes in a magnetic field. Originally discovered in the TMTSF-based conductors, these effects are particularly pronounced in the related system (DMET){sub 2}I{sub 3}. Here, experimental and computational results for magnetoresistance oscillations in this material, over a wide range of magnetic field orientations, are presented in such a manner as to uniquely highlight this multidimensional behavior. The calculations employ the Boltzmann transport equation that incorporates the system's triclinic crystal structure, which allows for accurate estimates of the transfer integrals along the crystallographic axes, verifying the 1D, 2D and 3D nature of (DMET){sub 2}I{sub 3}, as well as crossovers between dimensions in the electronic behavior.
ERIC Educational Resources Information Center
Brown, Helen; Meyers, Bernice; Schmidt, William
1999-01-01
Marbles were successfully used to help primary students develop concepts of motion. Marble-unit activities began with shaking and rattling inference bags and predicting by listening just how many marbles were in each bag. Students made qualitative and quantitative observations of the marbles, manipulated marbles with a partner, and observed…
ERIC Educational Resources Information Center
Gluck, P.; Krakower, Zeev
2010-01-01
We present a unit comprising theory, simulation and experiment for a body oscillating on a vertical spring, in which the simultaneous use of a force probe and an ultrasonic range finder enables one to explore quantitatively and understand many aspects of simple and damped harmonic motions. (Contains 14 figures.)
Introducing Simple Harmonic Motion.
ERIC Educational Resources Information Center
Roche, John
2002-01-01
Explains the origin and significance of harmonic motion which is an important topic that has wide application in the world. Describes the phenomenon by using an auxiliary circle to help illustrate the key relationships between acceleration, displacement, time, velocity, and phase. (Contains 16 references.) (Author/YDS)
NASA Technical Reports Server (NTRS)
Pepe, S.; Pepe, W. D.; Strauss, A. M.
1976-01-01
A general theory of orthodontic motion is developed that can be applied to determine the forces necessary to induce a given tooth to move to the predetermined desirable position. It is assumed that the natural (nonorthodontic) forces may be represented by a periodic function and the orthodontic forces may be superimposed upon the natural forces. A simple expression is derived for the applied stress.
NASA Technical Reports Server (NTRS)
Chandler, J. A. (Inventor)
1985-01-01
The linear motion valve is described. The valve spool employs magnetically permeable rings, spaced apart axially, which engage a sealing assembly having magnetically permeable pole pieces in magnetic relationship with a magnet. The gap between the ring and the pole pieces is sealed with a ferrofluid. Depletion of the ferrofluid is minimized.
Wiimote Experiments: Circular Motion
ERIC Educational Resources Information Center
Kouh, Minjoon; Holz, Danielle; Kawam, Alae; Lamont, Mary
2013-01-01
The advent of new sensor technologies can provide new ways of exploring fundamental physics. In this paper, we show how a Wiimote, which is a handheld remote controller for the Nintendo Wii video game system with an accelerometer, can be used to study the dynamics of circular motion with a very simple setup such as an old record player or a…
ERIC Educational Resources Information Center
Riddle, Bob
2005-01-01
All the planets in the solar system revolve around the Sun in the same direction, clockwise when viewed from above the North Pole. This is referred to as direct motion. From the perspective on the Earth's surface, the planets travel east across the sky in relation to the background of stars. The Sun also moves eastward daily, but this is an…
Wiimote Experiments: Circular Motion
NASA Astrophysics Data System (ADS)
Kouh, Minjoon; Holz, Danielle; Kawam, Alae; Lamont, Mary
2013-03-01
The advent of new sensor technologies can provide new ways of exploring fundamental physics. In this paper, we show how a Wiimote, which is a handheld remote controller for the Nintendo Wii video game system with an accelerometer, can be used to study the dynamics of circular motion with a very simple setup such as an old record player or a bicycle wheel.
ERIC Educational Resources Information Center
Ballard, David M.
1990-01-01
Examines the characteristics of three types of motion detectors: Doppler radar, infrared, and ultrasonic wave, and how they are used on school buses to prevent students from being killed by their own school bus. Other safety devices cited are bus crossing arms and a camera monitor system. (MLF)
Boynton, J.A.
1994-12-31
A World in Motion is a physical science curriculum supplement for grades four, five, and six which responds to the need to promote and teach sound science and mathematics concepts. Using the A World in Motion kits, teachers work in partnership with practicing engineer or scientists volunteers to provide students with fun, exciting, and relevant hands-on science and math experiences. During the A World in Motion experience, students work together in {open_quotes}Engineering Design Teams{close_quotes} exploring physics concepts through a series of activities. Each student is assigned a role as either a facilities engineer, development engineer, test engineer, or project engineer and is given responsibilities paralleling those of engineers in industry. The program culminates in a {open_quotes}Design Review{close_quotes} where students can communicate their results, demonstrate their designs, and receive recognition for their efforts. They are given a chance to take on responsibility and build self-esteem. Since January 1991, over 12,000 volunteers engineers have been involved with the program, with a distribution of 20,000 A World in Motion kit throughout the U.S. and Canada.
ERIC Educational Resources Information Center
Treschman, Keith
2009-01-01
At noon throughout the year the Sun has a north-south and east-west motion around the meridian. Earliest/latest sunrises and sunsets do not occur at the solstices and the effect is more pronounced with decreasing latitude. This phenomenon is calculated for 25 Australian cities and the following observations are recorded: (1) The latest sunrise…
ERIC Educational Resources Information Center
Lucie, Pierre
1979-01-01
Analyzes projectile motion using symmetry and simple geometry. Deduces the direction of velocity at any point, range, time of flight, maximum height, safety parabola, and maximum range for a projectile launched upon a plane inclined at any angle with respect to the horizontal. (Author/GA)
Do Fish Perceive Illusory Motion?
Gori, Simone; Agrillo, Christian; Dadda, Marco; Bisazza, Angelo
2014-01-01
Motion illusion refers to a perception of motion that is absent or different in the physical stimulus. These illusions are a powerful non-invasive tool for understanding the neurobiology of vision because they tell us, indirectly, how we process motion. There is general agreement in ascribing motion illusion to higher-level processing in the visual cortex, but debate remains about the exact role of eye movements and cortical networks in triggering it. Surprisingly, there have been no studies investigating global illusory motion evoked by static patterns in animal species other than humans. Herein, we show that fish perceive one of the most studied motion illusions, the Rotating Snakes. Fish responded similarly to real and illusory motion. The demonstration that complex global illusory motion is not restricted to humans and can be found even in species that do not have a cortex paves the way to develop animal models to study the neurobiological bases of motion perception. PMID:25246001
Motion dominance in binocular rivalry depends on extraretinal motions.
Nakayama, Ryohei; Motoyoshi, Isamu; Sato, Takao
2016-01-01
In binocular rivalry, moving stimulus is dominant over stationary stimulus. This is called motion dominance. The motion here is usually a motion defined on the retina (retinal motion). However, motion can be defined in several different coordinates. It can be defined with respect to objects in the background (object-based motion) or to observers' head or body (spatiotopic motion), as well as to the retinal coordinate. In this study, we examined the role of motions defined by these three coordinates. A dichoptic pair of gratings was presented to create a binocular rivalry, one of which was moving and the other stationary. A fixation point and a reference background were either moving with the grating or stationary, depending on the condition. Different combinations of the three types of motions were created by having the observer track the fixation point or the background when they are moving. It was found that the retinal motion does not necessarily yield motion dominance, and that the motion dominance is determined by the combination of motions defined by different coordinate systems.
Minster, B.; Prescott, W.; Royden, L.
1991-02-01
Our goal is to understand the motions of the plates, the deformation along their boundaries and within their interiors, and the processes that control these tectonic phenomena. In the broadest terms, we must strive to understand the relationships of regional and local deformation to flow in the upper mantle and the rheological, thermal and density structure of the lithosphere. The essential data sets which we require to reach our goal consist of maps of current strain rates at the earth's surface and the distribution of integrated deformation through time as recorded in the geologic record. Our success will depend on the effective synthesis of crustal kinematics with a variety of other geological and geophysical data, within a quantitative theoretical framework describing processes in the earth's interior. Only in this way can we relate the snapshot of current motions and earth structure provided by geodetic and geophysical data with long-term processes operating on the time scales relevant to most geological processes. The wide-spread use of space-based techniques, coupled with traditional geological and geophysical data, promises a revolution in our understanding of the kinematics and dynamics of plate motions over a broad range of spatial and temporal scales and in a variety of geologic settings. The space-based techniques that best address problems in plate motion and deformation are precise space-geodetic positioning -- on land and on the seafloor -- and satellite acquisition of detailed altimetric and remote sensing data in oceanic and continental areas. The overall science objectives for the NASA Solid Earth Science plan for the 1990's, are to Understand the motion and deformation of the lithosphere within and across plate boundaries'', and to understand the dynamics of the mantle, the structure and evolution of the lithosphere, and the landforms that result from local and regional deformation. 57 refs., 7 figs., 2 tabs.
Computational Motion Phantoms and Statistical Models of Respiratory Motion
NASA Astrophysics Data System (ADS)
Ehrhardt, Jan; Klinder, Tobias; Lorenz, Cristian
Breathing motion is not a robust and 100 % reproducible process, and inter- and intra-fractional motion variations form an important problem in radiotherapy of the thorax and upper abdomen. A widespread consensus nowadays exists that it would be useful to use prior knowledge about respiratory organ motion and its variability to improve radiotherapy planning and treatment delivery. This chapter discusses two different approaches to model the variability of respiratory motion. In the first part, we review computational motion phantoms, i.e. computerized anatomical and physiological models. Computational phantoms are excellent tools to simulate and investigate the effects of organ motion in radiation therapy and to gain insight into methods for motion management. The second part of this chapter discusses statistical modeling techniques to describe the breathing motion and its variability in a population of 4D images. Population-based models can be generated from repeatedly acquired 4D images of the same patient (intra-patient models) and from 4D images of different patients (inter-patient models). The generation of those models is explained and possible applications of those models for motion prediction in radiotherapy are exemplified. Computational models of respiratory motion and motion variability have numerous applications in radiation therapy, e.g. to understand motion effects in simulation studies, to develop and evaluate treatment strategies or to introduce prior knowledge into the patient-specific treatment planning.
Seismic interferometry by multidimensional deconvolution without wavefield separation
NASA Astrophysics Data System (ADS)
Ravasi, Matteo; Meles, Giovanni; Curtis, Andrew; Rawlinson, Zara; Yikuo, Liu
2015-07-01
Seismic interferometry comprises a suite of methods to redatum recorded wavefields to those that would have been recorded if different sources (so-called virtual sources) had been activated. Seismic interferometry by cross-correlation has been formulated using either two-way (for full wavefields) or one-way (for directionally decomposed wavefields) representation theorems. To obtain improved Green's function estimates, the cross-correlation result can be deconvolved by a quantity that identifies the smearing of the virtual source in space and time, the so-called point-spread function. This type of interferometry, known as interferometry by multidimensional deconvolution (MDD), has so far been applied only to one-way directionally decomposed fields, requiring accurate wavefield decomposition from dual (e.g. pressure and velocity) recordings. Here we propose a form of interferometry by multidimensional deconvolution that uses full wavefields with two-way representations, and simultaneously invert for pressure and (normal) velocity Green's functions, rather than only velocity responses as for its one-way counterpart. Tests on synthetic data show that two-way MDD improves on results of interferometry by cross-correlation, and generally produces estimates of similar quality to those obtained by one-way MDD, suggesting that the preliminary decomposition into up- and downgoing components of the pressure field is not required if pressure and velocity data are jointly used in the deconvolution. We also show that constraints on the directionality of the Green's functions sought can be added directly into the MDD inversion process to further improve two-way multidimensional deconvolution. Finally, as a by-product of having pressure and particle velocity measurements, we adapt one- and two-way representation theorems to convert any particle velocity receiver into its corresponding virtual dipole/gradient source by means of MDD. Thus data recorded from standard monopolar (e
NASA Technical Reports Server (NTRS)
Watson, Andrew B. (Inventor); Ahumada, Albert J. (Inventor)
2014-01-01
A method of measuring motion blur is disclosed comprising obtaining a moving edge temporal profile r(sub 1)(k) of an image of a high-contrast moving edge, calculating the masked local contrast m(sub1)(k) for r(sub 1)(k) and the masked local contrast m(sub 2)(k) for an ideal step edge waveform r(sub 2)(k) with the same amplitude as r(sub 1)(k), and calculating the measure or motion blur Psi as a difference function, The masked local contrasts are calculated using a set of convolution kernels scaled to simulate the performance of the human visual system, and Psi is measured in units of just-noticeable differences.
NASA Technical Reports Server (NTRS)
Ford, A. G. (Inventor)
1977-01-01
A motion-restraining device for dissipating at a controlled rate the force of a moving body is discussed. The device is characterized by a drive shaft adapted to be driven in rotation by a moving body connected to a tape wound about a reel mounted on the drive shaft, and an elongated pitman link having one end pivotally connected to the crankshaft and the opposite end thereof connected with the mass through an energy dissipating linkage. A shuttle is disposed within a slot and guided by rectilinear motion between a pair of spaced impact surfaces. Reaction forces applied at impact of the shuttle with the impact surfaces include oppositely projected force components angularly related to the direction of the applied impact forces.
Enhancing Privacy in Participatory Sensing Applications with Multidimensional Data
Forrest, Stephanie; He, Wenbo; Groat, Michael; Edwards, Benjamin; Horey, James L
2013-01-01
Participatory sensing applications rely on individuals to share personal data to produce aggregated models and knowledge. In this setting, privacy concerns can discourage widespread adoption of new applications. We present a privacy-preserving participatory sensing scheme based on negative surveys for both continuous and multivariate categorical data. Without relying on encryption, our algorithms enhance the privacy of sensed data in an energy and computation efficient manner. Simulations and implementation on Android smart phones illustrate how multidimensional data can be aggregated in a useful and privacy-enhancing manner.
Intrinsic irreversibility limits the efficiency of multidimensional molecular motors.
Jack, M W; Tumlin, C
2016-05-01
We consider the efficiency limits of Brownian motors able to extract work from the temperature difference between reservoirs or from external thermodynamic forces. These systems can operate in a variety of modes, including as isothermal engines, heat engines, refrigerators, and heat pumps. We derive analytical results showing that certain classes of multidimensional Brownian motor, including the Smoluchowski-Feynman ratchet, are unable to attain perfect efficiency (Carnot efficiency for heat engines). This demonstrates the presence of intrinsic irreversibilities in their operating mechanism. We present numerical simulations showing that in some cases the loss process that limits efficiency is associated with vortices in the probability current.
Multi-dimensional ENO schemes for general geometries
NASA Technical Reports Server (NTRS)
Harten, Ami; Chakravarthy, Sukumar R.
1991-01-01
A class of ENO schemes is presented for the numerical solution of multidimensional hyperbolic systems of conservation laws in structured and unstructured grids. This is a class of shock-capturing schemes which are designed to compute cell-averages to high order accuracy. The ENO scheme is composed of a piecewise-polynomial reconstruction of the solution form its given cell-averages, approximate evolution of the resulting initial value problem, and averaging of this approximate solution over each cell. The reconstruction algorithm is based on an adaptive selection of stencil for each cell so as to avoid spurious oscillations near discontinuities while achieving high order of accuracy away from them.
Multi-Scale Multi-Dimensional Ion Battery Performance Model
2007-05-07
The Multi-Scale Multi-Dimensional (MSMD) Lithium Ion Battery Model allows for computer prediction and engineering optimization of thermal, electrical, and electrochemical performance of lithium ion cells with realistic geometries. The model introduces separate simulation domains for different scale physics, achieving much higher computational efficiency compared to the single domain approach. It solves a one dimensional electrochemistry model in a micro sub-grid system, and captures the impacts of macro-scale battery design factors on cell performance and materialmore » usage by solving cell-level electron and heat transports in a macro grid system.« less
Multidimensional electron-photon transport with standard discrete ordinates codes
Drumm, C.R.
1995-12-31
A method is described for generating electron cross sections that are compatible with standard discrete ordinates codes without modification. There are many advantages of using an established discrete ordinates solver, e.g. immediately available adjoint capability. Coupled electron-photon transport capability is needed for many applications, including the modeling of the response of electronics components to space and man-made radiation environments. The cross sections have been successfully used in the DORT, TWODANT and TORT discrete ordinates codes. The cross sections are shown to provide accurate and efficient solutions to certain multidimensional electronphoton transport problems.
Overview of the BISON Multidimensional Fuel Performance Code
R. L. Williamson; J. D. Hales; S. R. Novascone; B. W. Spencer; D. M. Perez; G. Pastore; R. C. Martineau
2013-10-01
BISON is a modern multidimensional multiphysics finite-element based nuclear fuel performance code that has been under development at the Idaho National Laboratory (USA) since 2009. A brief background is provided on the code’s computational framework (MOOSE), governing equations, and material and behavioral models. Ongoing code verification and validation work is outlined, and comparative results are provided for select validation cases. Recent applications are discussed, including specific description of two applications where 3D treatment is important. A summary of future code development and validation activities is given. Numerous references to published work are provided where interested readers can find more complete information.
Analysis of world economic variables using multidimensional scaling.
Machado, J A Tenreiro; Mata, Maria Eugénia
2015-01-01
Waves of globalization reflect the historical technical progress and modern economic growth. The dynamics of this process are here approached using the multidimensional scaling (MDS) methodology to analyze the evolution of GDP per capita, international trade openness, life expectancy, and education tertiary enrollment in 14 countries. MDS provides the appropriate theoretical concepts and the exact mathematical tools to describe the joint evolution of these indicators of economic growth, globalization, welfare and human development of the world economy from 1977 up to 2012. The polarization dance of countries enlightens the convergence paths, potential warfare and present-day rivalries in the global geopolitical scene.
Intrinsic irreversibility limits the efficiency of multidimensional molecular motors
NASA Astrophysics Data System (ADS)
Jack, M. W.; Tumlin, C.
2016-05-01
We consider the efficiency limits of Brownian motors able to extract work from the temperature difference between reservoirs or from external thermodynamic forces. These systems can operate in a variety of modes, including as isothermal engines, heat engines, refrigerators, and heat pumps. We derive analytical results showing that certain classes of multidimensional Brownian motor, including the Smoluchowski-Feynman ratchet, are unable to attain perfect efficiency (Carnot efficiency for heat engines). This demonstrates the presence of intrinsic irreversibilities in their operating mechanism. We present numerical simulations showing that in some cases the loss process that limits efficiency is associated with vortices in the probability current.
Analysis of world economic variables using multidimensional scaling.
Machado, J A Tenreiro; Mata, Maria Eugénia
2015-01-01
Waves of globalization reflect the historical technical progress and modern economic growth. The dynamics of this process are here approached using the multidimensional scaling (MDS) methodology to analyze the evolution of GDP per capita, international trade openness, life expectancy, and education tertiary enrollment in 14 countries. MDS provides the appropriate theoretical concepts and the exact mathematical tools to describe the joint evolution of these indicators of economic growth, globalization, welfare and human development of the world economy from 1977 up to 2012. The polarization dance of countries enlightens the convergence paths, potential warfare and present-day rivalries in the global geopolitical scene. PMID:25811177
Revealing and Characterizing Dark Excitons through Coherent Multidimensional Spectroscopy.
Tollerud, Jonathan O; Cundiff, Steven T; Davis, Jeffrey A
2016-08-26
Dark excitons are of fundamental importance in a broad range of contexts but are difficult to study using conventional optical spectroscopy due to their weak interaction with light. We show how coherent multidimensional spectroscopy can reveal and characterize dark states. Using this approach, we identify parity-forbidden and spatially indirect excitons in InGaAs/GaAs quantum wells and determine details regarding lifetimes, homogeneous and inhomogeneous linewidths, broadening mechanisms, and coupling strengths. The observations of coherent coupling between these states and bright excitons hint at a role for a multistep process by which excitons in the barrier can relax into the quantum wells. PMID:27610881
A multidimensional approach for selecting child care workers.
Jones, J W; Joy, D S; Martin, S L
1990-10-01
A multidimensional selection battery was designed to predict a variety of criteria important in the selection of child care workers. The battery assesses constructs related to honesty, violence, substance abuse, emotional stability and safety. A series of studies were used to test the validity of the selection battery. Scores on the test battery were compared with those from three alternative selection procedures to define the measured constructs. Three additional studies show the relation of scores on the selection battery and the behavior of child care workers. The test battery was correlated with the job performance of child care workers and identified adults convicted for sexual offenses against minors. PMID:2263707
Multi-dimensional Hermite polynomials in quantum optics
NASA Astrophysics Data System (ADS)
Kok, Pieter; Braunstein, Samuel L.
2001-08-01
We study a class of optical circuits with vacuum input states consisting of Gaussian sources without coherent displacements such as down-converters and squeezers, together with photo-detectors and passive interferometry (beamsplitters, polarization rotations, phase-shifters, etc). We show that the outgoing state leaving the optical circuit can be expressed in terms of so-called multi-dimensional Hermite polynomials and give their recursion and orthogonality relations. We show how quantum teleportation of single-photon polarization states can be modelled using this description.
Intrinsic irreversibility limits the efficiency of multidimensional molecular motors.
Jack, M W; Tumlin, C
2016-05-01
We consider the efficiency limits of Brownian motors able to extract work from the temperature difference between reservoirs or from external thermodynamic forces. These systems can operate in a variety of modes, including as isothermal engines, heat engines, refrigerators, and heat pumps. We derive analytical results showing that certain classes of multidimensional Brownian motor, including the Smoluchowski-Feynman ratchet, are unable to attain perfect efficiency (Carnot efficiency for heat engines). This demonstrates the presence of intrinsic irreversibilities in their operating mechanism. We present numerical simulations showing that in some cases the loss process that limits efficiency is associated with vortices in the probability current. PMID:27300832
Revealing and Characterizing Dark Excitons through Coherent Multidimensional Spectroscopy
NASA Astrophysics Data System (ADS)
Tollerud, Jonathan O.; Cundiff, Steven T.; Davis, Jeffrey A.
2016-08-01
Dark excitons are of fundamental importance in a broad range of contexts but are difficult to study using conventional optical spectroscopy due to their weak interaction with light. We show how coherent multidimensional spectroscopy can reveal and characterize dark states. Using this approach, we identify parity-forbidden and spatially indirect excitons in InGaAs/GaAs quantum wells and determine details regarding lifetimes, homogeneous and inhomogeneous linewidths, broadening mechanisms, and coupling strengths. The observations of coherent coupling between these states and bright excitons hint at a role for a multistep process by which excitons in the barrier can relax into the quantum wells.
Nursing care systematization as a multidimensional and interactive phenomenon.
Backes, Dirce Stein; Koerich, Magda Santos; Nascimento, Keyla Cristiane do; Erdmann, Alacoque Lorenzini
2008-01-01
This study aimed to understand the meaning of Nursing Care Systematization (NCS) for multiprofessional health team professionals based on the relationships, interactions and associations of Complex thought. This qualitative study uses Grounded Theory as a methodological reference framework. Data were obtained through interviews with three sample groups, totaling 15 professionals from different institutions. Simultaneous data codification and analysis identified the central theme: 'Glimpsing nursing care systematization as an interactive and multidimensional phenomenon' and the respective reference model. NCS appoints, in addition to interactivity and professional complementarity, the importance of dialog and connection between the academy, health practices and regulatory offices, based on new reference frameworks for the organization of health practices.
Multidimensional electronic spectroscopy of phycobiliproteins from cryptophyte algae
NASA Astrophysics Data System (ADS)
Turner, Daniel
2011-03-01
We describe new spectroscopic measurements which reveal additional information regarding the observed quantum coherences in proteins extracted from photosynthetic algae. The proteins we investigate are the phycobiliproteins phycoerythrin 545 and phycocyanin 645. Two new avenues have been explored. We describe how changes to the chemical and biological environment impact the quantum coherence present in the 2D electronic correlation spectrum. We also use new multidimensional spectroscopic techniques to reveal insights into the nature of the quantum coherence and the nature of the participating states.
Analysis of World Economic Variables Using Multidimensional Scaling
Machado, J.A. Tenreiro; Mata, Maria Eugénia
2015-01-01
Waves of globalization reflect the historical technical progress and modern economic growth. The dynamics of this process are here approached using the multidimensional scaling (MDS) methodology to analyze the evolution of GDP per capita, international trade openness, life expectancy, and education tertiary enrollment in 14 countries. MDS provides the appropriate theoretical concepts and the exact mathematical tools to describe the joint evolution of these indicators of economic growth, globalization, welfare and human development of the world economy from 1977 up to 2012. The polarization dance of countries enlightens the convergence paths, potential warfare and present-day rivalries in the global geopolitical scene. PMID:25811177
Safdari, Hadiseh; Chechkin, Aleksei V; Jafari, Gholamreza R; Metzler, Ralf
2015-04-01
Scaled Brownian motion (SBM) is widely used to model anomalous diffusion of passive tracers in complex and biological systems. It is a highly nonstationary process governed by the Langevin equation for Brownian motion, however, with a power-law time dependence of the noise strength. Here we study the aging properties of SBM for both unconfined and confined motion. Specifically, we derive the ensemble and time averaged mean squared displacements and analyze their behavior in the regimes of weak, intermediate, and strong aging. A very rich behavior is revealed for confined aging SBM depending on different aging times and whether the process is sub- or superdiffusive. We demonstrate that the information on the aging factorizes with respect to the lag time and exhibits a functional form that is identical to the aging behavior of scale-free continuous time random walk processes. While SBM exhibits a disparity between ensemble and time averaged observables and is thus weakly nonergodic, strong aging is shown to effect a convergence of the ensemble and time averaged mean squared displacement. Finally, we derive the density of first passage times in the semi-infinite domain that features a crossover defined by the aging time. PMID:25974439
NASA Astrophysics Data System (ADS)
Hori, Takayuki; Ohya, Jun; Kurumisawa, Jun
2011-03-01
We propose a Tensor Decomposition based algorithm that recognizes the observed action performed by an unknown person and unknown viewpoint not included in the database. Our previous research aimed motion recognition from one single viewpoint. In this paper, we extend our approach for human motion recognition from an arbitrary viewpoint. To achieve this issue, we set tensor database which are multi-dimensional vectors with dimensions corresponding to human models, viewpoint angles, and action classes. The value of a tensor for a given combination of human silhouette model, viewpoint angle, and action class is the series of mesh feature vectors calculated each frame sequence. To recognize human motion, the actions of one of the persons in the tensor are replaced by the synthesized actions. Then, the core tensor for the replaced tensor is computed. This process is repeated for each combination of action, person, and viewpoint. For each iteration, the difference between the replaced and original core tensors is computed. The assumption that gives the minimal difference is the action recognition result. The recognition results show the validity of our proposed method, the method is experimentally compared with Nearest Neighbor rule. Our proposed method is very stable as each action was recognized with over 75% accuracy.
Subsonic Flow for the Multidimensional Euler-Poisson System
NASA Astrophysics Data System (ADS)
Bae, Myoungjean; Duan, Ben; Xie, Chunjing
2016-04-01
We establish the existence and stability of subsonic potential flow for the steady Euler-Poisson system in a multidimensional nozzle of a finite length when prescribing the electric potential difference on a non-insulated boundary from a fixed point at the exit, and prescribing the pressure at the exit of the nozzle. The Euler-Poisson system for subsonic potential flow can be reduced to a nonlinear elliptic system of second order. In this paper, we develop a technique to achieve a priori {C^{1,α}} estimates of solutions to a quasi-linear second order elliptic system with mixed boundary conditions in a multidimensional domain enclosed by a Lipschitz continuous boundary. In particular, we discovered a special structure of the Euler-Poisson system which enables us to obtain {C^{1,α}} estimates of the velocity potential and the electric potential functions, and this leads us to establish structural stability of subsonic flows for the Euler-Poisson system under perturbations of various data.
Towards a multidimensional root trait framework: a tree root review.
Weemstra, Monique; Mommer, Liesje; Visser, Eric J W; van Ruijven, Jasper; Kuyper, Thomas W; Mohren, Godefridus M J; Sterck, Frank J
2016-09-01
Contents 1159 I. 1159 II. 1161 III. 1164 IV. 1166 1167 References 1167 SUMMARY: The search for a root economics spectrum (RES) has been sparked by recent interest in trait-based plant ecology. By analogy with the one-dimensional leaf economics spectrum (LES), fine-root traits are hypothesised to match leaf traits which are coordinated along one axis from resource acquisitive to conservative traits. However, our literature review and meta-level analysis reveal no consistent evidence of an RES mirroring an LES. Instead the RES appears to be multidimensional. We discuss three fundamental differences contributing to the discrepancy between these spectra. First, root traits are simultaneously constrained by various environmental drivers not necessarily related to resource uptake. Second, above- and belowground traits cannot be considered analogues, because they function differently and might not be related to resource uptake in a similar manner. Third, mycorrhizal interactions may offset selection for an RES. Understanding and explaining the belowground mechanisms and trade-offs that drive variation in root traits, resource acquisition and plant performance across species, thus requires a fundamentally different approach than applied aboveground. We therefore call for studies that can functionally incorporate the root traits involved in resource uptake, the complex soil environment and the various soil resource uptake mechanisms - particularly the mycorrhizal pathway - in a multidimensional root trait framework.
Aggression in borderline personality disorder: A multidimensional model.
Mancke, Falk; Herpertz, Sabine C; Bertsch, Katja
2015-07-01
This article proposes a multidimensional model of aggression in borderline personality disorder (BPD) from the perspective of the biobehavioral dimensions of affective dysregulation, impulsivity, threat hypersensitivity, and empathic functioning. It summarizes data from studies that investigated these biobehavioral dimensions using self-reports, behavioral tasks, neuroimaging, neurochemistry as well as psychophysiology, and identifies the following alterations: (a) affective dysregulation associated with prefrontal-limbic imbalance, enhanced heart rate reactivity, skin conductance, and startle response; (b) impulsivity also associated with prefrontal-limbic imbalance, central serotonergic dysfunction, more electroencephalographic slow wave activity, and reduced P300 amplitude in a 2-tone discrimination task; (c) threat hypersensitivity associated with enhanced perception of anger in ambiguous facial expressions, greater speed and number of reflexive eye movements to angry eyes (shown to be compensated by exogenous oxytocin), enhanced P100 amplitude in response to blends of happy versus angry facial expressions, and prefrontal-limbic imbalance; (d) reduced cognitive empathy associated with reduced activity in the superior temporal sulcus/gyrus and preliminary findings of lower oxytocinergic and higher vasopressinergic activity; and (e) reduced self-other differentiation associated with greater emotional simulation and hyperactivation of the somatosensory cortex. These biobehavioral dimensions can be nicely linked to conceptual terms of the alternative Diagnostic and Statistical Manual of Mental Disorders, fifth edition (DSM-5) model of BPD, and thus to a multidimensional rather than a traditional categorical approach. PMID:26191822
PCA feature extraction for change detection in multidimensional unlabeled data.
Kuncheva, Ludmila I; Faithfull, William J
2014-01-01
When classifiers are deployed in real-world applications, it is assumed that the distribution of the incoming data matches the distribution of the data used to train the classifier. This assumption is often incorrect, which necessitates some form of change detection or adaptive classification. While there has been a lot of work on change detection based on the classification error monitored over the course of the operation of the classifier, finding changes in multidimensional unlabeled data is still a challenge. Here, we propose to apply principal component analysis (PCA) for feature extraction prior to the change detection. Supported by a theoretical example, we argue that the components with the lowest variance should be retained as the extracted features because they are more likely to be affected by a change. We chose a recently proposed semiparametric log-likelihood change detection criterion that is sensitive to changes in both mean and variance of the multidimensional distribution. An experiment with 35 datasets and an illustration with a simple video segmentation demonstrate the advantage of using extracted features compared to raw data. Further analysis shows that feature extraction through PCA is beneficial, specifically for data with multiple balanced classes.
Extended Darknet: Multi-Dimensional Internet Threat Monitoring System
NASA Astrophysics Data System (ADS)
Shimoda, Akihiro; Mori, Tatsuya; Goto, Shigeki
Internet threats caused by botnets/worms are one of the most important security issues to be addressed. Darknet, also called a dark IP address space, is one of the best solutions for monitoring anomalous packets sent by malicious software. However, since darknet is deployed only on an inactive IP address space, it is an inefficient way for monitoring a working network that has a considerable number of active IP addresses. The present paper addresses this problem. We propose a scalable, light-weight malicious packet monitoring system based on a multi-dimensional IP/port analysis. Our system significantly extends the monitoring scope of darknet. In order to extend the capacity of darknet, our approach leverages the active IP address space without affecting legitimate traffic. Multi-dimensional monitoring enables the monitoring of TCP ports with firewalls enabled on each of the IP addresses. We focus on delays of TCP syn/ack responses in the traffic. We locate syn/ack delayed packets and forward them to sensors or honeypots for further analysis. We also propose a policy-based flow classification and forwarding mechanism and develop a prototype of a monitoring system that implements our proposed architecture. We deploy our system on a campus network and perform several experiments for the evaluation of our system. We verify that our system can cover 89% of the IP addresses while darknet-based monitoring only covers 46%. On our campus network, our system monitors twice as many IP addresses as darknet.
Multidimensional epistasis and fitness landscapes in enzyme evolution.
Zhang, Wei; Dourado, Daniel F A R; Fernandes, Pedro Alexandrino; Ramos, Maria João; Mannervik, Bengt
2012-07-01
The conventional analysis of enzyme evolution is to regard one single salient feature as a measure of fitness, expressed in a milieu exposing the possible selective advantage at a given time and location. Given that a single protein may serve more than one function, fitness should be assessed in several dimensions. In the present study we have explored individual mutational steps leading to a triple-point-mutated human GST (glutathione transferase) A2-2 displaying enhanced activity with azathioprine. A total of eight alternative substrates were used to monitor the diverse evolutionary trajectories. The epistatic effects of the mutations on catalytic activity were variable in sign and magnitude and depended on the substrate used, showing that epistasis is a multidimensional quality. Evidently, the multidimensional fitness landscape can lead to alternative trajectories resulting in enzymes optimized for features other than the selectable markers relevant at the origin of the evolutionary process. In this manner the evolutionary response is robust and can adapt to changing environmental conditions. PMID:22533640
NMRPipe: a multidimensional spectral processing system based on UNIX pipes.
Delaglio, F; Grzesiek, S; Vuister, G W; Zhu, G; Pfeifer, J; Bax, A
1995-11-01
The NMRPipe system is a UNIX software environment of processing, graphics, and analysis tools designed to meet current routine and research-oriented multidimensional processing requirements, and to anticipate and accommodate future demands and developments. The system is based on UNIX pipes, which allow programs running simultaneously to exchange streams of data under user control. In an NMRPipe processing scheme, a stream of spectral data flows through a pipeline of processing programs, each of which performs one component of the overall scheme, such as Fourier transformation or linear prediction. Complete multidimensional processing schemes are constructed as simple UNIX shell scripts. The processing modules themselves maintain and exploit accurate records of data sizes, detection modes, and calibration information in all dimensions, so that schemes can be constructed without the need to explicitly define or anticipate data sizes or storage details of real and imaginary channels during processing. The asynchronous pipeline scheme provides other substantial advantages, including high flexibility, favorable processing speeds, choice of both all-in-memory and disk-bound processing, easy adaptation to different data formats, simpler software development and maintenance, and the ability to distribute processing tasks on multi-CPU computers and computer networks.
Automated multidimensional single molecule fluorescence microscopy feature detection and tracking.
Rolfe, Daniel J; McLachlan, Charles I; Hirsch, Michael; Needham, Sarah R; Tynan, Christopher J; Webb, Stephen E D; Martin-Fernandez, Marisa L; Hobson, Michael P
2011-10-01
Characterisation of multi-protein interactions in cellular networks can be achieved by optical microscopy using multidimensional single molecule fluorescence imaging. Proteins of different species, individually labelled with a single fluorophore, can be imaged as isolated spots (features) of different colour light in different channels, and their diffusive behaviour in cells directly measured through time. Challenges in data analysis have, however, thus far hindered its application in biology. A set of methods for the automated analysis of multidimensional single molecule microscopy data from cells is presented, incorporating Bayesian segmentation-based feature detection, image registration and particle tracking. Single molecules of different colours can be simultaneously detected in noisy, high background data with an arbitrary number of channels, acquired simultaneously or time-multiplexed, and then tracked through time. The resulting traces can be further analysed, for example to detect intensity steps, count discrete intensity levels, measure fluorescence resonance energy transfer (FRET) or changes in polarisation. Examples are shown illustrating the use of the algorithms in investigations of the epidermal growth factor receptor (EGFR) signalling network, a key target for cancer therapeutics, and with simulated data.
The multidimensional self-adaptive grid code, SAGE
NASA Technical Reports Server (NTRS)
Davies, Carol B.; Venkatapathy, Ethiraj
1992-01-01
This report describes the multidimensional self-adaptive grid code SAGE. A two-dimensional version of this code was described in an earlier report by the authors. The formulation of the multidimensional version is described in the first section of this document. The second section is presented in the form of a user guide that explains the input and execution of the code and provides many examples. Successful application of the SAGE code in both two and three dimensions for the solution of various flow problems has proven the code to be robust, portable, and simple to use. Although the basic formulation follows the method of Nakahashi and Deiwert, many modifications have been made to facilitate the use of the self-adaptive grid method for complex grid structures. Modifications to the method and the simplified input options make this a flexible and user-friendly code. The new SAGE code can accommodate both two-dimensional and three-dimensional flow problems.
Dirac-bracket structure in multidimensional mode conversion
NASA Astrophysics Data System (ADS)
Brizard, A. J.; Tracy, E. R.; Kaufman, A. N.; Johnston, D.; Zobin, N.
2012-05-01
The intersection of two (2 n - 1)-dimensional dispersion manifolds Da and Db in the 2 n-dimensional ray phase space P yields a (2 n - 2)-dimensional conversion manifold M≡Da∩Db that naturally possesses a Dirac-bracket structure that is inherited from the canonical Poisson bracket on ray phase space. The canonical symplectic two-form Ω ≡ Ω∥ + Ω⊥, defined on the 2 n-dimensional tangent plane TP≡TM⊕(TM)⊥, can thus be decomposed into the Dirac two-form Ω∥ on the (2 n - 2)-dimensional tangent plane TM at a conversion point z0∈M, and the symplectic two-form Ω⊥ on its orthogonal 2-dimensional complement (TM)⊥. These two symplectic two-forms are introduced in our analysis of multidimensional mode conversion, where their respective geometrical roles are defined. We note that since the Dirac-bracket structure Ω∥ vanishes identically when n = 1, it represents a new structure in multidimensional ( n > 1) mode conversion theory.
A multidimensional approach to apathy after traumatic brain injury.
Arnould, Annabelle; Rochat, Lucien; Azouvi, Philippe; Van der Linden, Martial
2013-09-01
Apathy is commonly described following traumatic brain injury (TBI) and is associated with serious consequences, notably for patients' participation in rehabilitation, family life and later social reintegration. There is strong evidence in the literature of the multidimensional nature of apathy (behavioural, cognitive and emotional), but the processes underlying each dimension are still unclear. The purpose of this article is first, to provide a critical review of the current definitions and instruments used to measure apathy in neurological and psychiatric disorders, and second, to review the prevalence, characteristics, neuroanatomical correlates, relationships with other neurobehavioural disorders and mechanisms of apathy in the TBI population. In this context, we propose a new multidimensional framework that takes into account the various mechanisms at play in the facets of apathy, including not only cognitive factors, especially executive, but also affective factors (e.g., negative mood), motivational variables (e.g., anticipatory pleasure) and aspects related to personal identity (e.g., self-esteem). Future investigations that consider these various factors will help improve the understanding of apathy. This theoretical framework opens up relevant prospects for better clinical assessment and rehabilitation of these frequently described motivational disorders in patients with brain injury. PMID:23921453
Multidimensional NMR inversion without Kronecker products: Multilinear inversion.
Medellín, David; Ravi, Vivek R; Torres-Verdín, Carlos
2016-08-01
Multidimensional NMR inversion using Kronecker products poses several challenges. First, kernel compression is only possible when the kernel matrices are separable, and in recent years, there has been an increasing interest in NMR sequences with non-separable kernels. Second, in three or more dimensions, the singular value decomposition is not unique; therefore kernel compression is not well-defined for higher dimensions. Without kernel compression, the Kronecker product yields matrices that require large amounts of memory, making the inversion intractable for personal computers. Finally, incorporating arbitrary regularization terms is not possible using the Lawson-Hanson (LH) or the Butler-Reeds-Dawson (BRD) algorithms. We develop a minimization-based inversion method that circumvents the above problems by using multilinear forms to perform multidimensional NMR inversion without using kernel compression or Kronecker products. The new method is memory efficient, requiring less than 0.1% of the memory required by the LH or BRD methods. It can also be extended to arbitrary dimensions and adapted to include non-separable kernels, linear constraints, and arbitrary regularization terms. Additionally, it is easy to implement because only a cost function and its first derivative are required to perform the inversion. PMID:27209370
Multidimensional NMR inversion without Kronecker products: Multilinear inversion
NASA Astrophysics Data System (ADS)
Medellín, David; Ravi, Vivek R.; Torres-Verdín, Carlos
2016-08-01
Multidimensional NMR inversion using Kronecker products poses several challenges. First, kernel compression is only possible when the kernel matrices are separable, and in recent years, there has been an increasing interest in NMR sequences with non-separable kernels. Second, in three or more dimensions, the singular value decomposition is not unique; therefore kernel compression is not well-defined for higher dimensions. Without kernel compression, the Kronecker product yields matrices that require large amounts of memory, making the inversion intractable for personal computers. Finally, incorporating arbitrary regularization terms is not possible using the Lawson-Hanson (LH) or the Butler-Reeds-Dawson (BRD) algorithms. We develop a minimization-based inversion method that circumvents the above problems by using multilinear forms to perform multidimensional NMR inversion without using kernel compression or Kronecker products. The new method is memory efficient, requiring less than 0.1% of the memory required by the LH or BRD methods. It can also be extended to arbitrary dimensions and adapted to include non-separable kernels, linear constraints, and arbitrary regularization terms. Additionally, it is easy to implement because only a cost function and its first derivative are required to perform the inversion.
Multidimensionality in host manipulation mimicked by serotonin injection
Perrot-Minnot, Marie-Jeanne; Sanchez-Thirion, Kevin; Cézilly, Frank
2014-01-01
Manipulative parasites often alter the phenotype of their hosts along multiple dimensions. ‘Multidimensionality’ in host manipulation could consist in the simultaneous alteration of several physiological pathways independently of one another, or proceed from the disruption of some key physiological parameter, followed by a cascade of effects. We compared multidimensionality in ‘host manipulation’ between two closely related amphipods, Gammarus fossarum and Gammarus pulex, naturally and experimentally infected with Pomphorhynchus laevis (Acanthocephala), respectively. To that end, we calculated in each host–parasite association the effect size of the difference between infected and uninfected individuals for six different traits (activity, phototaxis, geotaxis, attraction to conspecifics, refuge use and metabolic rate). The effects sizes were highly correlated between host–parasite associations, providing evidence for a relatively constant ‘infection syndrome’. Using the same methodology, we compared the extent of phenotypic alterations induced by an experimental injection of serotonin (5-HT) in uninfected G. pulex to that induced by experimental or natural infection with P. laevis. We observed a significant correlation between effect sizes across the six traits, indicating that injection with 5-HT can faithfully mimic the ‘infection syndrome’. This is, to our knowledge, the first experimental evidence that multidimensionality in host manipulation can proceed, at least partly, from the disruption of some major physiological mechanism. PMID:25339729
Manycore Performance-Portability: Kokkos Multidimensional Array Library
Edwards, H. Carter; Sunderland, Daniel; Porter, Vicki; Amsler, Chris; Mish, Sam
2012-01-01
Large, complex scientific and engineering application code have a significant investment in computational kernels to implement their mathematical models. Porting these computational kernels to the collection of modern manycore accelerator devices is a major challenge in that these devices have diverse programming models, application programming interfaces (APIs), and performance requirements. The Kokkos Array programming model provides library-based approach to implement computational kernels that are performance-portable to CPU-multicore and GPGPU accelerator devices. This programming model is based upon three fundamental concepts: (1) manycore compute devices each with its own memory space, (2) data parallel kernels and (3) multidimensional arrays. Kernel executionmore » performance is, especially for NVIDIA® devices, extremely dependent on data access patterns. Optimal data access pattern can be different for different manycore devices – potentially leading to different implementations of computational kernels specialized for different devices. The Kokkos Array programming model supports performance-portable kernels by (1) separating data access patterns from computational kernels through a multidimensional array API and (2) introduce device-specific data access mappings when a kernel is compiled. An implementation of Kokkos Array is available through Trilinos [Trilinos website, http://trilinos.sandia.gov/, August 2011].« less
Situation exploration in a persistent surveillance system with multidimensional data
NASA Astrophysics Data System (ADS)
Habibi, Mohammad S.
2013-03-01
There is an emerging need for fusing hard and soft sensor data in an efficient surveillance system to provide accurate estimation of situation awareness. These mostly abstract, multi-dimensional and multi-sensor data pose a great challenge to the user in performing analysis of multi-threaded events efficiently and cohesively. To address this concern an interactive Visual Analytics (VA) application is developed for rapid assessment and evaluation of different hypotheses based on context-sensitive ontology spawn from taxonomies describing human/human and human/vehicle/object interactions. A methodology is described here for generating relevant ontology in a Persistent Surveillance System (PSS) and demonstrates how they can be utilized in the context of PSS to track and identify group activities pertaining to potential threats. The proposed VA system allows for visual analysis of raw data as well as metadata that have spatiotemporal representation and content-based implications. Additionally in this paper, a technique for rapid search of tagged information contingent to ranking and confidence is explained for analysis of multi-dimensional data. Lastly the issue of uncertainty associated with processing and interpretation of heterogeneous data is also addressed.
Neural Prediction of Multidimensional Decisions in Monkey Superior Colliculus
NASA Astrophysics Data System (ADS)
Hasegawa, Ryohei P.; Hasegawa, Yukako T.; Segraves, Mark A.
To examine the function of the superior colliculus (SC) in decision-making processes and the application of its single trial activity for “neural mind reading,” we recorded from SC deep layers while two monkeys performed oculomotor go/no-go tasks. We have recently focused on monitoring single trial activities in single SC neurons, and designed a virtual decision function (VDF) to provide a good estimation of single-dimensional decisions (go/no-go decisions for a cue presented at a specific visual field, a response field of each neuron). In this study, we used two VDFs for multidimensional decisions (go/no-go decisions at two cue locations) with the ensemble activity which was simultaneously recorded from a small group (4 to 6) of neurons at both sides of the SC. VDFs predicted cue locations as well as go/no-go decisions. These results suggest that monitoring of ensemble SC activity had sufficient capacity to predict multidimensional decisions on a trial-by-trial basis, which is an ideal candidate to serve for cognitive brain-machine interfaces (BMI) such as two-dimensional word spellers.
Monte Carlo methods for multidimensional integration for European option pricing
NASA Astrophysics Data System (ADS)
Todorov, V.; Dimov, I. T.
2016-10-01
In this paper, we illustrate examples of highly accurate Monte Carlo and quasi-Monte Carlo methods for multiple integrals related to the evaluation of European style options. The idea is that the value of the option is formulated in terms of the expectation of some random variable; then the average of independent samples of this random variable is used to estimate the value of the option. First we obtain an integral representation for the value of the option using the risk neutral valuation formula. Then with an appropriations change of the constants we obtain a multidimensional integral over the unit hypercube of the corresponding dimensionality. Then we compare a specific type of lattice rules over one of the best low discrepancy sequence of Sobol for numerical integration. Quasi-Monte Carlo methods are compared with Adaptive and Crude Monte Carlo techniques for solving the problem. The four approaches are completely different thus it is a question of interest to know which one of them outperforms the other for evaluation multidimensional integrals in finance. Some of the advantages and disadvantages of the developed algorithms are discussed.
A New Online Calibration Method for Multidimensional Computerized Adaptive Testing.
Chen, Ping; Wang, Chun
2016-09-01
Multidimensional-Method A (M-Method A) has been proposed as an efficient and effective online calibration method for multidimensional computerized adaptive testing (MCAT) (Chen & Xin, Paper presented at the 78th Meeting of the Psychometric Society, Arnhem, The Netherlands, 2013). However, a key assumption of M-Method A is that it treats person parameter estimates as their true values, thus this method might yield erroneous item calibration when person parameter estimates contain non-ignorable measurement errors. To improve the performance of M-Method A, this paper proposes a new MCAT online calibration method, namely, the full functional MLE-M-Method A (FFMLE-M-Method A). This new method combines the full functional MLE (Jones & Jin in Psychometrika 59:59-75, 1994; Stefanski & Carroll in Annals of Statistics 13:1335-1351, 1985) with the original M-Method A in an effort to correct for the estimation error of ability vector that might otherwise adversely affect the precision of item calibration. Two correction schemes are also proposed when implementing the new method. A simulation study was conducted to show that the new method generated more accurate item parameter estimation than the original M-Method A in almost all conditions. PMID:26608960
Flexible multi-dimensional modulation method for elastic optical networks
NASA Astrophysics Data System (ADS)
He, Zilong; Liu, Wentao; Shi, Sheping; Shen, Bailin; Chen, Xue; Gao, Xiqing; Zhang, Qi; Shang, Dongdong; Ji, Yongning; Liu, Yingfeng
2016-01-01
We demonstrate a flexible multi-dimensional modulation method for elastic optical networks. We compare the flexible multi-dimensional modulation formats PM-kSC-mQAM with traditional modulation formats PM-mQAM using numerical simulations in back-to-back and wavelength division multiplexed (WDM) transmission (50 GHz-spaced) scenarios at the same symbol rate of 32 Gbaud. The simulation results show that PM-kSC-QPSK and PM-kSC-16QAM can achieve obvious back-to-back sensitivity gain with respect to PM-QPSK and PM-16QAM at the expense of spectral efficiency reduction. And the WDM transmission simulation results show that PM-2SC-QPSK can achieve 57.5% increase in transmission reach compared to PM-QPSK, and 48.5% increase for PM-2SC-16QAM over PM-16QAM. Furthermore, we also experimentally investigate the back to back performance of PM-2SC-QPSK, PM-4SC-QPSK, PM-2SC-16QAM and PM-3SC-16QAM, and the experimental results agree well with the numerical simulations.
Relativistic kinematics and stationary motions
NASA Astrophysics Data System (ADS)
Russo, Jorge G.; Townsend, Paul K.
2009-11-01
The relativistic jerk, snap and all higher-order kinematical D-vectors are defined for the motion of a massive particle in a D-dimensional Minkowski spacetime. We illustrate the formalism with stationary motions, for which we provide a new, Lorentz covariant, classification. We generalize some cases to branes, explaining the relevance to uniform motion in a heat bath. We also consider some non-stationary motions, including motion with constant proper jerk, and free fall into a black hole as viewed from a GEMS perspective.
EDITORIAL: Nanotechnology in motion Nanotechnology in motion
NASA Astrophysics Data System (ADS)
Demming, Anna
2012-02-01
, Toshio Ando from the University of Kanazawa provides an overview of developments that have allowed atomic force microscopy to move from rates of the order of one frame a minute to over a thousand frames per second in constant height mode, as reported by Mervyn Miles and colleagues at Bristol University and University College London [8]. Among the pioneers in the field, Ando's group demonstrated the ability to record the Brownian motion of myosin V molecules on mica with image capture rates of 100 x 100 pixels in 80 ms over a decade ago [9]. The developments unleash the potential of atomic force microscopy to observe the dynamics of biological and materials systems. If seeing is believing, the ability to present real motion pictures of the nanoworld cannot fail to capture the public imagination and stimulate burgeoning new avenues of scientific endeavour. Nearly 350 years on from the publication Micrographia, images in microscopy have moved from the page to the movies. References [1] Binnig G, Quate C F, and Gerber Ch 1986 Phys. Rev. Lett. 56 930-3 [2] Ando T 2012 Nanotechnology 23 062001 [3] J G 1934 Nature 134 635-6 [4] Bharadwaj P, Anger P and Novotny L 2007 Nanotechnology 18 044017 [5] The Nobel Prize in Physics 1986 Nobelprize.org [6] Kim K K, Reina A, Shi Y, Park H, Li L-J, Lee Y H and Kong J 2010 Nanotechnology 21 285205 [7] Phillips D B, Grieve J A, Olof S N, Kocher S J, Bowman R, Padgett M J, Miles M J and Carberry D M 2011 Nanotechnology 22 285503 [8] Picco L M, Bozec L, Ulcinas A, Engledew D J, Antognozzi M, Horton M A and Miles M J 2007 Nanotechnology 18 044030 [9] Ando T, Kodera N, Takai E, Maruyama D, Saito K and Toda A 2001 Proc. Natl. Acad. Sci. 98 12468
ERIC Educational Resources Information Center
Min, Shangchao; He, Lianzhen
2014-01-01
This study examined the relative effectiveness of the multidimensional bi-factor model and multidimensional testlet response theory (TRT) model in accommodating local dependence in testlet-based reading assessment with both dichotomously and polytomously scored items. The data used were 14,089 test-takers' item-level responses to the…
Bifactor Approach to Modeling Multidimensionality of Physical Self-Perception Profile
ERIC Educational Resources Information Center
Chung, ChihMing; Liao, Xiaolan; Song, Hairong; Lee, Taehun
2016-01-01
The multi-dimensionality of Physical Self-Perception Profile (PSPP) has been acknowledged by the use of correlated-factor model and second-order model. In this study, the authors critically endorse the bifactor model, as a substitute to address the multi-dimensionality of PSPP. To cross-validate the models, analyses are conducted first in…
On Multi-Dimensional Vocabulary Teaching Mode for College English Teaching
ERIC Educational Resources Information Center
Zhou, Li-na
2010-01-01
This paper analyses the major approaches in EFL (English as a Foreign Language) vocabulary teaching from historical perspective and puts forward multi-dimensional vocabulary teaching mode for college English. The author stresses that multi-dimensional approaches of communicative vocabulary teaching, lexical phrase teaching method, the grammar…
ERIC Educational Resources Information Center
Lee, Eunjung
2013-01-01
The purpose of this research was to compare the equating performance of various equating procedures for the multidimensional tests. To examine the various equating procedures, simulated data sets were used that were generated based on a multidimensional item response theory (MIRT) framework. Various equating procedures were examined, including…
Posterior Predictive Model Checking for Conjunctive Multidimensionality in Item Response Theory
ERIC Educational Resources Information Center
Levy, Roy
2011-01-01
If data exhibit multidimensionality, key conditional independence assumptions of unidimensional models do not hold. The current work pursues posterior predictive model checking (PPMC) as a tool for criticizing models due to unaccounted for dimensions in data structures that follow conjunctive multidimensional models. These pursuits are couched in…
ERIC Educational Resources Information Center
Clark, W. Crawford; Ferrer-Brechner, Theresa
Multidimensional scaling (MDS) offers a rigorous approach to many problems in perception, emotion, personality, and cognition, where the stimuli are too complex to be quantified by other means. In these procedures similarity ratings of the stimulus objects are modeled as points in multidimensional space, such that perceived similarity is…
ERIC Educational Resources Information Center
Karatas, Zeynep; Tagay, Ozlem
2012-01-01
The purpose of this study is to determine whether there is a relationship between self-esteem, locus of control and multidimensional perfectionism, and the extent to which the variables of self-esteem, locus of control and multidimensional perfectionism contribute to the prediction of subjective well-being. The study was carried out with 318 final…
ERIC Educational Resources Information Center
Findler, Liora; Vilchinsky, Noa; Werner, Shirli
2007-01-01
This study presents the development of a new instrument, the "Multidimensional Attitudes Scale Toward Persons With Disabilities" (MAS). Based on the multidimensional approach, it posits that attitudes are composed of three dimensions: affect, cognition, and behavior. The scale was distributed to a sample of 132 people along with a self-esteem…
Health, Wealth and Wisdom: Exploring Multidimensional Inequality in a Developing Country
ERIC Educational Resources Information Center
Nilsson, Therese
2010-01-01
Despite a broad theoretical literature on multidimensional inequality and a widespread belief that welfare is not synonymous to income--not the least in a developing context--empirical inequality examinations rarely includes several welfare attributes. We explore three techniques on how to evaluate multidimensional inequality using Zambian…
ERIC Educational Resources Information Center
Odekar, Anshula; Hallowell, Brooke
2005-01-01
Purpose: Multidimensional scoring methods yield valuable information about communication abilities. However, issues of training demands for valid and reliable scoring, especially in current service delivery contexts, may preclude common usage. Alternatives to multidimensional scoring were investigated in a sample of adults with aphasia. Method:…
ERIC Educational Resources Information Center
Coromaldi, Manuela; Zoli, Mariangela
2012-01-01
Theoretical and empirical studies have recently adopted a multidimensional concept of poverty. There is considerable debate about the most appropriate degree of multidimensionality to retain in the analysis. In this work we add to the received literature in two ways. First, we derive indicators of multiple deprivation by applying a particular…
Effects of Multidimensional Concept Maps on Fourth Graders' Learning in Web-Based Computer Course
ERIC Educational Resources Information Center
Huang, Hwa-Shan; Chiou, Chei-Chang; Chiang, Heien-Kun; Lai, Sung-Hsi; Huang, Chiun-Yen; Chou, Yin-Yu
2012-01-01
This study explores the effect of multidimensional concept mapping instruction on students' learning performance in a web-based computer course. The subjects consisted of 103 fourth graders from an elementary school in central Taiwan. They were divided into three groups: multidimensional concept map (MCM) instruction group, Novak concept map (NCM)…
Item Vector Plots for the Multidimensional Three-Parameter Logistic Model
ERIC Educational Resources Information Center
Bryant, Damon; Davis, Larry
2011-01-01
This brief technical note describes how to construct item vector plots for dichotomously scored items fitting the multidimensional three-parameter logistic model (M3PLM). As multidimensional item response theory (MIRT) shows promise of being a very useful framework in the test development life cycle, graphical tools that facilitate understanding…
Can a Multidimensional Test Be Evaluated with Unidimensional Item Response Theory?
ERIC Educational Resources Information Center
Wiberg, Marie
2012-01-01
The aim of this study was to evaluate possible consequences of using unidimensional item response theory (UIRT) on a multidimensional college admission test. The test consists of 5 subscales and can be divided into two sections, that is, it can be considered both as a unidimensional and a multidimensional test. The test was examined with both UIRT…
ERIC Educational Resources Information Center
Baghaei, Purya
2013-01-01
This study aims to develop and validate a multidimensional scale of willingness to communicate in a foreign language. Multidimensional random coefficient multinomial logit model was employed to analyze the scale. Likelihood deviance test and information criteria showed that a three-dimensional model fits significantly better than a two-dimensional…
NASA Astrophysics Data System (ADS)
Akinci, A.; D'Amico, S.; Malagnini, L.
2010-12-01
In this study, we characterize the scaling of the ground motions for frequencies ranging between 0.25 and 5 Hz, obtaining results for seismic attenuation, geometrical spreading, and source parameters in Taiwan. We regressed this large number of weak-motion data in order to characterize the regional propagation and the absolute source scaling. Stochastic simulations are generated for finite-fault ruptures using the obtained parameters to predict the absolute peaks of the ground acceleration and velocity for several magnitude and distance range, as well as beyond the magnitude range of the weak-motion data set on which they are calculated. The predictions are then compared with recorded strong motion data and empirical ground motion prediction equation obtained for the study region. We showed that our regional parameters, obtained from independent weak-motion database, may be applied for evaluation of ground motion parameters for earthquakes of magnitude up to 7.6.
NASA Technical Reports Server (NTRS)
Badler, N. I.
1985-01-01
Human motion analysis is the task of converting actual human movements into computer readable data. Such movement information may be obtained though active or passive sensing methods. Active methods include physical measuring devices such as goniometers on joints of the body, force plates, and manually operated sensors such as a Cybex dynamometer. Passive sensing de-couples the position measuring device from actual human contact. Passive sensors include Selspot scanning systems (since there is no mechanical connection between the subject's attached LEDs and the infrared sensing cameras), sonic (spark-based) three-dimensional digitizers, Polhemus six-dimensional tracking systems, and image processing systems based on multiple views and photogrammetric calculations.
NASA Astrophysics Data System (ADS)
Salari, Valiollah
1991-07-01
This paper presents a computerized technique for quantitative analysis of the movement characteristics of spermatozoa. Stored video images of spermatozoa are digitized at a fixed time interval. The digital images are stored as a sequence of frames in a microcomputer. The analysis of the sequence comprises two main tasks: finding the location of the centroid for each sperm and tracking them over the entire sequences. Information from the motion of each moving cell will be used for tracking. Experimental results are presented to show the merits of the proposed algorithm for tracking.
Multidimensional Poverty and Health Status as a Predictor of Chronic Income Poverty.
Callander, Emily J; Schofield, Deborah J
2015-12-01
Longitudinal analysis of Wave 5 to 10 of the nationally representative Household, Income and Labour Dynamics in Australia dataset was undertaken to assess whether multidimensional poverty status can predict chronic income poverty. Of those who were multidimensionally poor (low income plus poor health or poor health and insufficient education attainment) in 2007, and those who were in income poverty only (no other forms of disadvantage) in 2007, a greater proportion of those in multidimensional poverty continued to be in income poverty for the subsequent 5 years through to 2012. People who were multidimensionally poor in 2007 had 2.17 times the odds of being in income poverty each year through to 2012 than those who were in income poverty only in 2005 (95% CI: 1.23-3.83). Multidimensional poverty measures are a useful tool for policymakers to identify target populations for policies aiming to improve equity and reduce chronic disadvantage.
Ha, Jinyong; Yoo, Hongki; Tearney, Guillermo J; Bouma, Brett E
2012-08-01
Intracoronary optical coherence tomography and optical frequency domain imaging (OFDI) have been utilized for two-dimensional and three-dimensional imaging of vascular microanatomy. Image quality and the spatial accuracy of multidimensional reconstructions, however, can be degraded due to artifacts resulting from relative motion between the intracoronary catheter and the vessel wall. To track the relative motion of a catheter with regard to the vessel, a motion tracking system was incorporated with a standard OFDI system by using wavelength division multiplexing techniques. Motion of the vessel was acquired by a frequency shift of the backscattered light caused by the Doppler effect. A single monochromatic beam was utilized for tracking the relative longitudinal displacements of a catheter-based fiber probe with regard to the vessel. Although two tracking beams are, in general, required to correct for longitudinal motion artifacts, the accurate reconstruction in a longitudinal view was achieved by the Doppler frequency information of a single beam. Our results demonstrate that the single beam based motion tracking scheme is a cost-effective, practical approach to compensating for longitudinal distortions due to cardiac dynamics, thus leading to accurate quantitative analysis of 3D intracoronary OFDI.
Fast local motion estimation algorithm using elementary motion detectors
NASA Astrophysics Data System (ADS)
Nakamura, Eiji; Nakamura, Takehito; Sawada, Katsutoshi
2003-06-01
This paper presnts a fast local motion estimation algorithm based on so called elementary motion detectors or EMDs. EMDs, modeling insect"s visual signal processing systems, have low computational complexity aspects and can thus be key components to realize such a fast local motion estimation algorithm. The contribution of the presented work is to introduce dual parameter estimators or DPEs by configuring EMDs so that they can estimate local motions in terms of both direction and speed mode parameters simultaneously. The estimated local motion vectors are displayed as arrows superimposed over video image frames. The developed algorithm is implmented in a DirectShow application by using Mircosoft"s DirectX runtime library and is evaluated using various types of video image sequences. It is found to be able to estimate local motion vectors in real time even in moderate PC computing platforms and hece no high profile hardware devices are needed for its real time operation.
Integrated Reproduction of Human Motion Components by Motion Copying System
NASA Astrophysics Data System (ADS)
Tsunashima, Noboru; Katsura, Seiichiro
Currently, the development of leading-edge technology for recording and loading human motion on the basis of haptic information is required in the field of manufacturing and human support. Human movement is an assembly of motion components. Since human movements should be supported by a robot in real time, it is necessary to integrate the morion components, which were saved earlier. Once such motion integration is realized, future technology for use in daily human life is developed. This paper proposes the integrated reproduction of the decomposed components of human motion by using a motion copying system. This system is the key technology for the realization of the acquisition, saving and reproduction of the real-world haptic information. By the proposed method, it is possible not only to achieve expert skill acquisition, skill transfer to robots, and power assist for each motion component but also to open up new areas of applications.
Hyun, Kyunglyul; Kim, Manmyung; Hwang, Youngseok; Lee, Jehee
2013-05-01
Simulating multiple character interaction is challenging because character actions must be carefully coordinated to align their spatial locations and synchronized with each other. We present an algorithm to create a dense crowd of virtual characters interacting with each other. The interaction may involve physical contacts, such as hand shaking, hugging, and carrying a heavy object collaboratively. We address the problem by collecting deformable motion patches, each of which describes an episode of multiple interacting characters, and tiling them spatially and temporally. The tiling of motion patches generates a seamless simulation of virtual characters interacting with each other in a non-trivial manner. Our tiling algorithm uses a combination of stochastic sampling and deterministic search to address the discrete and continuous aspects of the tiling problem. Our tiling algorithm made it possible to automatically generate highly-complex animation of multiple interacting characters. We achieved the level of complexity far beyond the current state-of-the-art animation techniques could generate, in terms of the diversity of human behaviors and the spatial/temporal density of interpersonal interactions. PMID:23669532
Hyun, Kyunglyul; Kim, Manmyung; Hwang, Youngseok; Lee, Jehee
2013-11-01
Simulating multiple character interaction is challenging because character actions must be carefully coordinated to align their spatial locations and synchronized with each other. We present an algorithm to create a dense crowd of virtual characters interacting with each other. The interaction may involve physical contacts, such as hand shaking, hugging, and carrying a heavy object collaboratively. We address the problem by collecting deformable motion patches, each of which describes an episode of multiple interacting characters, and tiling them spatially and temporally. The tiling of motion patches generates a seamless simulation of virtual characters interacting with each other in a nontrivial manner. Our tiling algorithm uses a combination of stochastic sampling and deterministic search to address the discrete and continuous aspects of the tiling problem. Our tiling algorithm made it possible to automatically generate highly complex animation of multiple interacting characters. We achieve the level of interaction complexity far beyond the current state of the art that animation techniques could generate, in terms of the diversity of human behaviors and the spatial/temporal density of interpersonal interactions. PMID:24029911
Stochastic blind motion deblurring.
Xiao, Lei; Gregson, James; Heide, Felix; Heidrich, Wolfgang
2015-10-01
Blind motion deblurring from a single image is a highly under-constrained problem with many degenerate solutions. A good approximation of the intrinsic image can, therefore, only be obtained with the help of prior information in the form of (often nonconvex) regularization terms for both the intrinsic image and the kernel. While the best choice of image priors is still a topic of ongoing investigation, this research is made more complicated by the fact that historically each new prior requires the development of a custom optimization method. In this paper, we develop a stochastic optimization method for blind deconvolution. Since this stochastic solver does not require the explicit computation of the gradient of the objective function and uses only efficient local evaluation of the objective, new priors can be implemented and tested very quickly. We demonstrate that this framework, in combination with different image priors produces results with Peak Signal-to-Noise Ratio (PSNR) values that match or exceed the results obtained by much more complex state-of-the-art blind motion deblurring algorithms. PMID:25974941
Multi-dimensional structure of accreting young stars
NASA Astrophysics Data System (ADS)
Geroux, C.; Baraffe, I.; Viallet, M.; Goffrey, T.; Pratt, J.; Constantino, T.; Folini, D.; Popov, M. V.; Walder, R.
2016-04-01
This work is the first attempt to describe the multi-dimensional structure of accreting young stars based on fully compressible time implicit multi-dimensional hydrodynamics simulations. One major motivation is to analyse the validity of accretion treatment used in previous 1D stellar evolution studies. We analyse the effect of accretion on the structure of a realistic stellar model of the young Sun. Our work is inspired by the numerical work of Kley & Lin (1996, ApJ, 461, 933) devoted to the structure of the boundary layer in accretion disks, which provides the outer boundary conditions for our simulations. We analyse the redistribution of accreted material with a range of values of specific entropy relative to the bulk specific entropy of the material in the accreting object's convective envelope. Low specific entropy accreted material characterises the so-called cold accretion process, whereas high specific entropy is relevant to hot accretion. A primary goal is to understand whether and how accreted energy deposited onto a stellar surface is redistributed in the interior. This study focusses on the high accretion rates characteristic of FU Ori systems. We find that the highest entropy cases produce a distinctive behaviour in the mass redistribution, rms velocities, and enthalpy flux in the convective envelope. This change in behaviour is characterised by the formation of a hot layer on the surface of the accreting object, which tends to suppress convection in the envelope. We analyse the long-term effect of such a hot buffer zone on the structure and evolution of the accreting object with 1D stellar evolution calculations. We study the relevance of the assumption of redistribution of accreted energy into the stellar interior used in the literature. We compare results obtained with the latter treatment and those obtained with a more physical accretion boundary condition based on the formation of a hot surface layer suggested by present multi-dimensional
Code of Federal Regulations, 2014 CFR
2014-04-01
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Code of Federal Regulations, 2010 CFR
2010-04-01
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Code of Federal Regulations, 2011 CFR
2011-04-01
... 24 Housing and Urban Development 1 2011-04-01 2011-04-01 false Motions. 26.16 Section 26.16... PROCEDURES Hearings Before Hearing Officers Pleadings and Motions § 26.16 Motions. (a) Motions. Requests for... a motion. All motions from the commencement of the action until the issuance of a decision shall...
Code of Federal Regulations, 2012 CFR
2012-04-01
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2013-04-01
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Multidimensional resonance raman spectroscopy by six-wave mixing in the deep UV
Molesky, Brian P.; Giokas, Paul G.; Guo, Zhenkun; Moran, Andrew M.
2014-09-21
Two-dimensional (2D) resonance Raman spectroscopies hold great potential for uncovering photoinduced relaxation processes in molecules but are not yet widely applied because of technical challenges. Here, we describe a newly developed 2D resonance Raman experiment operational at the third-harmonic of a Titanium-Sapphire laser. High-sensitivity and rapid data acquisition are achieved by combining spectral interferometry with a background-free (six-pulse) laser beam geometry. The third-harmonic laser pulses are generated in a filament produced by the fundamental and second-harmonic pulses in neon gas at pressures up to 35 atm. The capabilities of the setup are demonstrated by probing ground-state wavepacket motions in triiodide. The information provided by the experiment is explored with two different representations of the signal. In one representation, Fourier transforms are carried out with respect to the two experimentally controlled delay times to obtain a 2D Raman spectrum. Further insights are derived in a second representation by dispersing the signal pulse in a spectrometer. It is shown that, as in traditional pump-probe experiments, the six-wave mixing signal spectrum encodes the wavepacket's position by way of the (time-evolving) emission frequency. Anharmonicity additionally induces dynamics in the vibrational resonance frequency. In all cases, the experimental signals are compared to model calculations based on a cumulant expansion approach. This study suggests that multi-dimensional resonance Raman spectroscopies conducted on systems with Franck-Condon active modes are fairly immune to many of the technical issues that challenge off-resonant 2D Raman spectroscopies (e.g., third-order cascades) and photon-echo experiments in the deep UV (e.g., coherence spikes). The development of higher-order nonlinear spectroscopies operational in the deep UV is motivated by studies of biological systems and elementary organic photochemistries.
Multidimensional resonance Raman spectroscopy by six-wave mixing in the deep UV.
Molesky, Brian P; Giokas, Paul G; Guo, Zhenkun; Moran, Andrew M
2014-09-21
Two-dimensional (2D) resonance Raman spectroscopies hold great potential for uncovering photoinduced relaxation processes in molecules but are not yet widely applied because of technical challenges. Here, we describe a newly developed 2D resonance Raman experiment operational at the third-harmonic of a Titanium-Sapphire laser. High-sensitivity and rapid data acquisition are achieved by combining spectral interferometry with a background-free (six-pulse) laser beam geometry. The third-harmonic laser pulses are generated in a filament produced by the fundamental and second-harmonic pulses in neon gas at pressures up to 35 atm. The capabilities of the setup are demonstrated by probing ground-state wavepacket motions in triiodide. The information provided by the experiment is explored with two different representations of the signal. In one representation, Fourier transforms are carried out with respect to the two experimentally controlled delay times to obtain a 2D Raman spectrum. Further insights are derived in a second representation by dispersing the signal pulse in a spectrometer. It is shown that, as in traditional pump-probe experiments, the six-wave mixing signal spectrum encodes the wavepacket's position by way of the (time-evolving) emission frequency. Anharmonicity additionally induces dynamics in the vibrational resonance frequency. In all cases, the experimental signals are compared to model calculations based on a cumulant expansion approach. This study suggests that multi-dimensional resonance Raman spectroscopies conducted on systems with Franck-Condon active modes are fairly immune to many of the technical issues that challenge off-resonant 2D Raman spectroscopies (e.g., third-order cascades) and photon-echo experiments in the deep UV (e.g., coherence spikes). The development of higher-order nonlinear spectroscopies operational in the deep UV is motivated by studies of biological systems and elementary organic photochemistries. PMID:25240351
NASA Astrophysics Data System (ADS)
West, Ruth; Gossmann, Joachim; Margolis, Todd; Schulze, Jurgen P.; Lewis, J. P.; Hackbarth, Ben; Mostafavi, Iman
2009-02-01
ATLAS in silico is an interactive installation/virtual environment that provides an aesthetic encounter with metagenomics data (and contextual metadata) from the Global Ocean Survey (GOS). The installation creates a visceral experience of the abstraction of nature in to vast data collections - a practice that connects expeditionary science of the 19th Century with 21st Century expeditions like the GOS. Participants encounter a dream-like, highly abstract, and datadriven virtual world that combines the aesthetics of fine-lined copper engraving and grid-like layouts of 19th Century scientific representation with 21st Century digital aesthetics including wireframes and particle systems. It is resident at the Calit2 Immersive visualization Laboratory on the campus of UC San Diego, where it continues in active development. The installation utilizes a combination of infrared motion tracking, custom computer vision, multi-channel (10.1) spatialized interactive audio, 3D graphics, data sonification, audio design, networking, and the VarrierTM 60 tile, 100-million pixel barrier strip auto-stereoscopic display. Here we describe the physical and audio display systems for the installation and a hybrid strategy for multi-channel spatialized interactive audio rendering in immersive virtual reality that combines amplitude, delay and physical modeling-based, real-time spatialization approaches for enhanced expressivity in the virtual sound environment that was developed in the context of this artwork. The desire to represent a combination of qualitative and quantitative multidimensional, multi-scale data informs the artistic process and overall system design. We discuss the resulting aesthetic experience in relation to the overall system.
Regularized Multitask Learning for Multidimensional Log-Density Gradient Estimation.
Yamane, Ikko; Sasaki, Hiroaki; Sugiyama, Masashi
2016-07-01
Log-density gradient estimation is a fundamental statistical problem and possesses various practical applications such as clustering and measuring nongaussianity. A naive two-step approach of first estimating the density and then taking its log gradient is unreliable because an accurate density estimate does not necessarily lead to an accurate log-density gradient estimate. To cope with this problem, a method to directly estimate the log-density gradient without density estimation has been explored and demonstrated to work much better than the two-step method. The objective of this letter is to improve the performance of this direct method in multidimensional cases. Our idea is to regard the problem of log-density gradient estimation in each dimension as a task and apply regularized multitask learning to the direct log-density gradient estimator. We experimentally demonstrate the usefulness of the proposed multitask method in log-density gradient estimation and mode-seeking clustering.
New approach of color image quantization based on multidimensional directory
NASA Astrophysics Data System (ADS)
Chang, Chin-Chen; Su, Yuan-Yuan
2003-04-01
Color image quantization is a strategy in which a smaller number of colors are used to represent the image. The objective is to make the quality approximate as closely to the original true-color image. The technology is widely used in non-true-color displays and in color printers that cannot reproduce a large number of different colors. However, the main problem the quantization of color image has to face is how to use less colors to show the color image. Therefore, it is very important to choose one suitable palette for an index color image. In this paper, we shall propose a new approach which employs the concept of Multi-Dimensional Directory (MDD) together with the one cycle LBG algorithm to create a high-quality index color image. Compared with the approaches such as VQ, ISQ, and Photoshop v.5, our approach can not only acquire high quality image but also shorten the operation time.
Multidimensional coherent optical spectroscopy of semiconductor nanostructures: a review
NASA Astrophysics Data System (ADS)
Nardin, Gaël
2016-02-01
Multidimensional coherent optical spectroscopy (MDCS) is an elegant and versatile tool to measure the ultrafast nonlinear optical response of materials. Of particular interest for semiconductor nanostructures, MDCS enables the separation of homogeneous and inhomogeneous linewidths, reveals the nature of coupling between resonances, and is able to identify the signatures of many-body interactions. As an extension of transient four-wave mixing (FWM) experiments, MDCS can be implemented in various geometries, in which different strategies can be used to isolate the FWM signal and measure its phase. I review and compare different practical implementations of MDCS experiments adapted to the study of semiconductor materials. The power of MDCS is illustrated by discussing experimental results obtained on semiconductor nanostructures such as quantum dots, quantum wells, microcavities, and layered semiconductors.
Conservation laws for multidimensional systems and related linear algebra problems
NASA Astrophysics Data System (ADS)
Igonin, Sergei
2002-12-01
We consider multidimensional systems of PDEs of generalized evolution form with t-derivatives of arbitrary order on the left-hand side and with the right-hand side dependent on lower order t-derivatives and arbitrary space derivatives. For such systems we find an explicit necessary condition for the existence of higher conservation laws in terms of the system's symbol. For systems that violate this condition we give an effective upper bound on the order of conservation laws. Using this result, we completely describe conservation laws for viscous transonic equations, for the Brusselator model and the Belousov-Zhabotinskii system. To achieve this, we solve over an arbitrary field the matrix equations SA = AtS and SA = -AtS for a quadratic matrix A and its transpose At, which may be of independent interest.
Multidimensional Time-Resolved Spectroscopy of Vibrational Coherence in Biopolyenes
NASA Astrophysics Data System (ADS)
Buckup, Tiago; Motzkus, Marcus
2014-04-01
Multidimensional femtosecond time-resolved vibrational coherence spectroscopy allows one to investigate the evolution of vibrational coherence in electronic excited states. Methods such as pump-degenerate four-wave mixing and pump-impulsive vibrational spectroscopy combine an initial ultrashort laser pulse with a nonlinear probing sequence to reinduce vibrational coherence exclusively in the excited states. By carefully exploiting specific electronic resonances, one can detect vibrational coherence from 0 cm-1 to over 2,000 cm-1 and map its evolution. This review focuses on the observation and mapping of high-frequency vibrational coherence for all-trans biological polyenes such as Î²-carotene, lycopene, retinal, and retinal Schiff base. We discuss the role of molecular symmetry in vibrational coherence activity in the S1 electronic state and the interplay of coupling between electronic states and vibrational coherence.
Human tissue profiling with multidimensional protein identification technology.
Cagney, Gerard; Park, Stephen; Chung, Clement; Tong, Bianca; O'Dushlaine, Colm; Shields, Denis C; Emili, Andrew
2005-01-01
Profiling of tissues and cell types through systematic characterization of expressed genes or proteins shows promise as a basic research tool, and has potential applications in disease diagnosis and classification. We used multidimensional protein identification protein identification technology (MudPIT) to analyze proteomes for enriched nuclear extracts of eight human tissues: brain, heart, liver, lung, muscle, pancreas, spleen, and testis. We show that the method is approximately 80% reproducible. We address issues of relative abundance, tissue-specificity, and selectivity, and the significance of proteins whose expression does not correlate with that of the corresponding mRNA. Surprisingly, most proteins are detected in a single tissue. These proteins tend to fulfill specialist (and potentially tissue-specific) functions compared to proteins expressed in two or more tissues.
Multidimensional scaling analysis of the dynamics of a country economy.
Tenreiro Machado, J A; Mata, Maria Eugénia
2013-01-01
This paper analyzes the Portuguese short-run business cycles over the last 150 years and presents the multidimensional scaling (MDS) for visualizing the results. The analytical and numerical assessment of this long-run perspective reveals periods with close connections between the macroeconomic variables related to government accounts equilibrium, balance of payments equilibrium, and economic growth. The MDS method is adopted for a quantitative statistical analysis. In this way, similarity clusters of several historical periods emerge in the MDS maps, namely, in identifying similarities and dissimilarities that identify periods of prosperity and crises, growth, and stagnation. Such features are major aspects of collective national achievement, to which can be associated the impact of international problems such as the World Wars, the Great Depression, or the current global financial crisis, as well as national events in the context of broad political blueprints for the Portuguese society in the rising globalization process. PMID:24294132
A Multi-Dimensional Classification Model for Scientific Workflow Characteristics
Ramakrishnan, Lavanya; Plale, Beth
2010-04-05
Workflows have been used to model repeatable tasks or operations in manufacturing, business process, and software. In recent years, workflows are increasingly used for orchestration of science discovery tasks that use distributed resources and web services environments through resource models such as grid and cloud computing. Workflows have disparate re uirements and constraints that affects how they might be managed in distributed environments. In this paper, we present a multi-dimensional classification model illustrated by workflow examples obtained through a survey of scientists from different domains including bioinformatics and biomedical, weather and ocean modeling, astronomy detailing their data and computational requirements. The survey results and classification model contribute to the high level understandingof scientific workflows.
Multidimensional vector model of stimulus-response compatibility.
Yamaguchi, Motonori; Proctor, Robert W
2012-04-01
The present study proposes and examines the multidimensional vector (MDV) model framework as a modeling schema for choice response times. MDV extends the Thurstonian model, as well as signal detection theory, to classification tasks by taking into account the influence of response properties on stimulus discrimination. It is capable of accounting for stimulus-response compatibility, which is known to be an influential task variable determining choice-reaction performance but has not been considered in previous mathematical modeling efforts. Specific MDV models were developed for 5 experiments using the Simon task, for which stimulus location is task irrelevant, to examine the validity of model assumptions and illustrate characteristic behaviors of model parameters. The MDV models accounted for the experimental data to a remarkable degree, demonstrating the adequacy of the framework as a general schema for modeling the latency of choice performance. Some modeling issues involved in the MDV model framework are discussed.
Anonymous voting for multi-dimensional CV quantum system
NASA Astrophysics Data System (ADS)
Rong-Hua, Shi; Yi, Xiao; Jin-Jing, Shi; Ying, Guo; Moon-Ho, Lee
2016-06-01
We investigate the design of anonymous voting protocols, CV-based binary-valued ballot and CV-based multi-valued ballot with continuous variables (CV) in a multi-dimensional quantum cryptosystem to ensure the security of voting procedure and data privacy. The quantum entangled states are employed in the continuous variable quantum system to carry the voting information and assist information transmission, which takes the advantage of the GHZ-like states in terms of improving the utilization of quantum states by decreasing the number of required quantum states. It provides a potential approach to achieve the efficient quantum anonymous voting with high transmission security, especially in large-scale votes. Project supported by the National Natural Science Foundation of China (Grant Nos. 61272495, 61379153, and 61401519), the Research Fund for the Doctoral Program of Higher Education of China (Grant No. 20130162110012), and the MEST-NRF of Korea (Grant No. 2012-002521).
Multidimensional scaling of ferrous sulfate and basic tastes.
Stevens, David A; Smith, Rebecca F; Lawless, Harry T
2006-02-28
The status of metallic sensations as a primary or basic taste category is controversial. Ferrous sulfate (FeSO4) has been suggested as a prototypical metallic chemosensory stimulus. At least part of the metallic sensation from FeSO4 arises from a metallic retronasal smell. The quality of this sensation was studied via multidimensional scaling (MDS) of taste similarities, with and without nasal closure to eliminate retronasal olfactory sensations. The metallic stimulus was embedded in a series containing classical "basic taste" stimuli, alum and monosodium glutamate. With olfaction available, the metallic stimulus plotted away from basic tastes and taste mixtures. Scaled ratings of sensory properties related to metallic taste (iron-nail, copper-penny-like, aftertaste) of FeSO4 decreased with nasal closure. Results are consistent with the idea that ferrous sulfate produces a distinctly different sensation from the traditional basic tastes, which includes both olfactory and oral sensations.
Development and validation of the multidimensional state boredom scale.
Fahlman, Shelley A; Mercer-Lynn, Kimberley B; Flora, David B; Eastwood, John D
2013-02-01
This article describes the development and validation of the Multidimensional State Boredom Scale (MSBS)-the first and only full-scale measure of state boredom. It was developed based on a theoretically and empirically grounded definition of boredom. A five-factor structure of the scale (Disengagement, High Arousal, Low Arousal, Inattention, and Time Perception) was supported by exploratory factor analyses and confirmatory factor analyses of two independent samples. Furthermore, all subscales were significantly related to a single, second-order factor. The MSBS factor structure was shown to be invariant across gender. MSBS scores were significantly correlated with measures of trait boredom, depression, anxiety, anger, inattention, impulsivity, neuroticism, life satisfaction, and purpose in life. Finally, MSBS scores distinguished between participants who were experimentally manipulated into a state of boredom and those who were not, above and beyond measures of trait boredom, negative affect, and depression.
Development and validation of the multidimensional motivational climate observation system.
Smith, Nathan; Tessier, Damien; Tzioumakis, Yannis; Quested, Eleanor; Appleton, Paul; Sarrazin, Philippe; Papaioannou, Athanasios; Duda, Joan L
2015-02-01
This article outlines the development and validation of the Multidimensional Motivational Climate Observation System (MMCOS). Drawing from an integration of the dimensions of the social environment emphasized within achievement goal theory and self-determination theory (as assumed within Duda's [2013] conceptualization of "empowering" and "disempowering" climates), the MMCOS was developed to enable an objective assessment of the coach-created motivational environment in sport. Study 1 supported the initial validity and reliability of the newly developed observation system. Study 2 further examined the interobserver reliability and factorial structure of the MMCOS. Study 3 explored the predictive validity of the observational system in relation to athletes' reported basic psychological need satisfaction. Overall, the results of these studies provide preliminary support for the inter- and intraobserver reliability, as well as factorial and predictive validity of the MMCOS. Suggestions for the use of this observational system in future research in sport are provided.
Multidimensional stock network analysis: An Escoufier's RV coefficient approach
NASA Astrophysics Data System (ADS)
Lee, Gan Siew; Djauhari, Maman A.
2013-09-01
The current practice of stocks network analysis is based on the assumption that the time series of closed stock price could represent the behaviour of the each stock. This assumption leads to consider minimal spanning tree (MST) and sub-dominant ultrametric (SDU) as an indispensible tool to filter the economic information contained in the network. Recently, there is an attempt where researchers represent stock not only as a univariate time series of closed price but as a bivariate time series of closed price and volume. In this case, they developed the so-called multidimensional MST to filter the important economic information. However, in this paper, we show that their approach is only applicable for that bivariate time series only. This leads us to introduce a new methodology to construct MST where each stock is represented by a multivariate time series. An example of Malaysian stock exchange will be presented and discussed to illustrate the advantages of the method.
A Multidimensional Scaling Analysis of Students' Attitudes about Science Careers
NASA Astrophysics Data System (ADS)
Masnick, Amy M.; Stavros Valenti, S.; Cox, Brian D.; Osman, Christopher J.
2010-03-01
To encourage students to seek careers in Science, Technology, Engineering and Mathematics (STEM) fields, it is important to gauge students' implicit and explicit attitudes towards scientific professions. We asked high school and college students to rate the similarity of pairs of occupations, and then used multidimensional scaling (MDS) to create a spatial representation of occupational similarity. Other students confirmed the emergent MDS map by rating each of the occupations along several dimensions. We found that participants across age and sex considered scientific professions to be less creative and less people-oriented than other popular career choices. We conclude that students may be led away from STEM careers by common misperceptions that science is a difficult, uncreative, and socially isolating pursuit.
Lagrangian simulation of multidimensional anomalous transport at the MADE site
NASA Astrophysics Data System (ADS)
Zhang, Yong; Benson, David A.
2008-04-01
Contaminant transport through regional-scale natural geological formations typically exhibits several ``anomalous'' features, including direction-dependent spreading rates, channeling along preferential flow paths, trapping of solute in relatively immobile domains, and/or the local variation of transport speed. Simulating these plume characteristics can be computationally intensive using a traditional advection-dispersion equation (ADE) because anomalous features of transport generally depend on local-scale subsurface properties. Here we develop an alternative simulation approach that solves the full nonlocal, multidimensional, spatiotemporal fractional-order ADE with variable coefficients in a Lagrangian framework using a novel non-Markovian random walk method. This model allows us to simulate anomalous plumes without the need to explicitly define local-scale heterogeneity. The simple model accurately simulates the tritium plume measured at the extensively characterized MADE test site.
[Multidimensional counseling and intervention in anxiety problems in school].
Jeck, Stephan
2003-01-01
Multidimensional counselling and intervention in case of anxiety problems in school can be understood as a challenge for educational psychologists who has to solve individual anxiety disorders on the one hand and participate in processes of school development in order to prevent anxiety on the other hand. There are a lot of techniques and strategies to construct classroom settings which reduce anxiety. Improving self-efficacy and training stress management for teachers and students are possible programs presented in order to change the culture of educational organizations like schools. To realize such programs all members of the school community have to cooperate and teachers have to modify their instructional actions. Therefore they have to develop better diagnostic skills in order to detect anxious and inconspicuous students who need special fostering for better learning in school. For extreme anxiety disorders with school refusal there are many therapeutic treatments out of school, one of the best for children and adolescents are cognitive-behavioral settings.
Reinforcement learning in multidimensional environments relies on attention mechanisms.
Niv, Yael; Daniel, Reka; Geana, Andra; Gershman, Samuel J; Leong, Yuan Chang; Radulescu, Angela; Wilson, Robert C
2015-05-27
In recent years, ideas from the computational field of reinforcement learning have revolutionized the study of learning in the brain, famously providing new, precise theories of how dopamine affects learning in the basal ganglia. However, reinforcement learning algorithms are notorious for not scaling well to multidimensional environments, as is required for real-world learning. We hypothesized that the brain naturally reduces the dimensionality of real-world problems to only those dimensions that are relevant to predicting reward, and conducted an experiment to assess by what algorithms and with what neural mechanisms this "representation learning" process is realized in humans. Our results suggest that a bilateral attentional control network comprising the intraparietal sulcus, precuneus, and dorsolateral prefrontal cortex is involved in selecting what dimensions are relevant to the task at hand, effectively updating the task representation through trial and error. In this way, cortical attention mechanisms interact with learning in the basal ganglia to solve the "curse of dimensionality" in reinforcement learning.
Multidimensional scaling analysis of the dynamics of a country economy.
Tenreiro Machado, J A; Mata, Maria Eugénia
2013-01-01
This paper analyzes the Portuguese short-run business cycles over the last 150 years and presents the multidimensional scaling (MDS) for visualizing the results. The analytical and numerical assessment of this long-run perspective reveals periods with close connections between the macroeconomic variables related to government accounts equilibrium, balance of payments equilibrium, and economic growth. The MDS method is adopted for a quantitative statistical analysis. In this way, similarity clusters of several historical periods emerge in the MDS maps, namely, in identifying similarities and dissimilarities that identify periods of prosperity and crises, growth, and stagnation. Such features are major aspects of collective national achievement, to which can be associated the impact of international problems such as the World Wars, the Great Depression, or the current global financial crisis, as well as national events in the context of broad political blueprints for the Portuguese society in the rising globalization process.
Implementation fidelity of Multidimensional Family Therapy in an international trial.
Rowe, Cynthia; Rigter, Henk; Henderson, Craig; Gantner, Andreas; Mos, Kees; Nielsen, Philip; Phan, Olivier
2013-04-01
Implementation fidelity, a critical aspect of clinical trials research that establishes adequate delivery of the treatment as prescribed in treatment manuals and protocols, is also essential to the successful implementation of effective programs into new practice settings. Although infrequently studied in the drug abuse field, stronger implementation fidelity has been linked to better outcomes in practice but appears to be more difficult to achieve with greater distance from model developers. In the INternational CAnnabis Need for Treatment (INCANT) multi-national randomized clinical trial, investigators tested the effectiveness of Multidimensional Family Therapy (MDFT) in comparison to individual psychotherapy (IP) in Brussels, Berlin, Paris, The Hague, and Geneva with 450 adolescents with a cannabis use disorder and their parents. This study reports on the implementation fidelity of MDFT across these five Western European sites in terms of treatment adherence, dose and program differentiation, and discusses possible implications for international implementation efforts.
Anonymous voting for multi-dimensional CV quantum system
NASA Astrophysics Data System (ADS)
Rong-Hua, Shi; Yi, Xiao; Jin-Jing, Shi; Ying, Guo; Moon-Ho, Lee
2016-06-01
We investigate the design of anonymous voting protocols, CV-based binary-valued ballot and CV-based multi-valued ballot with continuous variables (CV) in a multi-dimensional quantum cryptosystem to ensure the security of voting procedure and data privacy. The quantum entangled states are employed in the continuous variable quantum system to carry the voting information and assist information transmission, which takes the advantage of the GHZ-like states in terms of improving the utilization of quantum states by decreasing the number of required quantum states. It provides a potential approach to achieve the efficient quantum anonymous voting with high transmission security, especially in large-scale votes. Project supported by the National Natural Science Foundation of China (Grant Nos. 61272495, 61379153, and 61401519), the Research Fund for the Doctoral Program of Higher Education of China (Grant No. 20130162110012), and the MEST-NRF of Korea (Grant No. 2012-002521).
Multidimensional Scaling Analysis of the Dynamics of a Country Economy
Mata, Maria Eugénia
2013-01-01
This paper analyzes the Portuguese short-run business cycles over the last 150 years and presents the multidimensional scaling (MDS) for visualizing the results. The analytical and numerical assessment of this long-run perspective reveals periods with close connections between the macroeconomic variables related to government accounts equilibrium, balance of payments equilibrium, and economic growth. The MDS method is adopted for a quantitative statistical analysis. In this way, similarity clusters of several historical periods emerge in the MDS maps, namely, in identifying similarities and dissimilarities that identify periods of prosperity and crises, growth, and stagnation. Such features are major aspects of collective national achievement, to which can be associated the impact of international problems such as the World Wars, the Great Depression, or the current global financial crisis, as well as national events in the context of broad political blueprints for the Portuguese society in the rising globalization process. PMID:24294132
Regularized Multitask Learning for Multidimensional Log-Density Gradient Estimation.
Yamane, Ikko; Sasaki, Hiroaki; Sugiyama, Masashi
2016-07-01
Log-density gradient estimation is a fundamental statistical problem and possesses various practical applications such as clustering and measuring nongaussianity. A naive two-step approach of first estimating the density and then taking its log gradient is unreliable because an accurate density estimate does not necessarily lead to an accurate log-density gradient estimate. To cope with this problem, a method to directly estimate the log-density gradient without density estimation has been explored and demonstrated to work much better than the two-step method. The objective of this letter is to improve the performance of this direct method in multidimensional cases. Our idea is to regard the problem of log-density gradient estimation in each dimension as a task and apply regularized multitask learning to the direct log-density gradient estimator. We experimentally demonstrate the usefulness of the proposed multitask method in log-density gradient estimation and mode-seeking clustering. PMID:27171983
Multidimensional time-resolved spectroscopy of vibrational coherence in biopolyenes.
Buckup, Tiago; Motzkus, Marcus
2014-01-01
Multidimensional femtosecond time-resolved vibrational coherence spectroscopy allows one to investigate the evolution of vibrational coherence in electronic excited states. Methods such as pump-degenerate four-wave mixing and pump-impulsive vibrational spectroscopy combine an initial ultrashort laser pulse with a nonlinear probing sequence to reinduce vibrational coherence exclusively in the excited states. By carefully exploiting specific electronic resonances, one can detect vibrational coherence from 0 cm(-1) to over 2,000 cm(-1) and map its evolution. This review focuses on the observation and mapping of high-frequency vibrational coherence for all-trans biological polyenes such as β-carotene, lycopene, retinal, and retinal Schiff base. We discuss the role of molecular symmetry in vibrational coherence activity in the S1 electronic state and the interplay of coupling between electronic states and vibrational coherence.
The Multi-Dimensional Character of Core-Collapse Supernovae
Hix, William Raphael; Lentz, E. J.; Bruenn, S. W.; Mezzacappa, Anthony; Messer, Bronson; Endeve, Eirik; Blondin, J. M.; Harris, James Austin; Marronetti, Pedro; Yakunin, Konstantin N
2016-01-01
Core-collapse supernovae, the culmination of massive stellar evolution, are spectacular astronomical events and the principle actors in the story of our elemental origins. Our understanding of these events, while still incomplete, centers around a neutrino-driven central engine that is highly hydrodynamically unstable. Increasingly sophisticated simulations reveal a shock that stalls for hundreds of milliseconds before reviving. Though brought back to life by neutrino heating, the development of the supernova explosion is inextricably linked to multi-dimensional fluid flows. In this paper, the outcomes of three-dimensional simulations that include sophisticated nuclear physics and spectral neutrino transport are juxtaposed to learn about the nature of the three dimensional fluid flow that shapes the explosion. Comparison is also made between the results of simulations in spherical symmetry from several groups, to give ourselves confidence in the understanding derived from this juxtaposition.
Estimating a treatment effect from multidimensional longitudinal data.
Gray, S M; Brookmeyer, R
1998-09-01
Multidimensional longitudinal data result when researchers measure an outcome through time that is quantified by many different response variables. These response variables are often defined on different numerical scales. The objective of this paper is to present a method to summarize and estimate an overall treatment effect from this type of longitudinal data. A regression model is proposed that assumes the treatment effect can be parameterized as an acceleration or deceleration of the time scale of each response variable's trajectory. Generalized estimating equations are used to estimate the model parameters. Cognitive and functional ability data from Alzheimer's disease patients and quality of life data from an AIDS clinical trial are used to illustrate the model.
Multidimensional modeling of pyrolysis gas transport inside orthotropic charring ablators
NASA Astrophysics Data System (ADS)
Weng, Haoyue
During hypersonic atmospheric entry, spacecraft are exposed to enormous aerodynamic heat. To prevent the payload from overheating, charring ablative materials are favored to be applied as the heat shield at the exposing surface of the vehicle. Accurate modeling not only prevents mission failures, but also helps reduce cost. Existing models were mostly limited to one-dimensional and discrepancies were shown against measured experiments and flight-data. To help improve the models and analyze the charring ablation problems, a multidimensional material response module is developed, based on a finite volume method framework. The developed computer program is verified through a series of test-cases, and through code-to-code comparisons with a validated code. Several novel models are proposed, including a three-dimensional pyrolysis gas transport model and an orthotropic material model. The effects of these models are numerically studied and demonstrated to be significant.
Towards a multi-dimensional approach to COPD.
Zanforlin, Alessandro; Sorino, Claudio; Sferrazza Papa, Giuseppe F
2016-06-01
Chronic obstructive pulmonary disease (COPD) is the third leading cause of mortality worldwide. Clinical features of the disease include exertional dyspnea and chronic cough, while persistent airflow obstruction detected at spirometry is the defining element of the disease. Notably, subjects with smoke exposure and symptoms, but normal FEV1/FVC ratio (previously classified as "stage 0" by the GOLD classification), are not considered affected and do not require treatment according to guidelines. The recent GeneCOPD study suggested that a proportion of this population might present significant radiological features of respiratory disease. This commentary article focuses on the possible future role of chest imaging, including ultrasound of the respiratory muscles, integrated with additional functional tests, such as body plethysmography and diffusing capacity for carbon monoxide of the lungs (DLCO), in a multidimensional assessment of COPD. PMID:27424499
Reconciling semiclassical and Bohmian mechanics. VI. Multidimensional dynamics
Poirier, Bill
2008-08-28
In previous articles [J. Chem. Phys. 121, 4501 (2004); J. Chem. Phys. 124, 034115 (2006); J. Chem. Phys. 124, 034116 (2006); J. Phys. Chem. A 111, 10400 (2007); J. Chem. Phys. 128, 164115 (2008)] an exact quantum, bipolar wave decomposition, {psi}={psi}{sub +}+{psi}{sub -}, was presented for one-dimensional stationary state and time-dependent wavepacket dynamics calculations, such that the components {psi}{sub {+-}} approach their semiclassical WKB analogs in the large action limit. The corresponding bipolar quantum trajectories are classical-like and well behaved, even when {psi} has many nodes or is wildly oscillatory. In this paper, both the stationary state and wavepacket dynamics theories are generalized for multidimensional systems and applied to several benchmark problems, including collinear H+H{sub 2}.
Acceleration of multi-dimensional propagator measurements with compressed sensing.
Paulsen, Jeffrey L; Cho, HyungJoon; Cho, Gyunggoo; Song, Yi-Qiao
2011-12-01
NMR can probe the microstructures of anisotropic materials such as liquid crystals, stretched polymers and biological tissues through measurement of the diffusion propagator, where internal structures are indicated by restricted diffusion. Multi-dimensional measurements can probe the microscopic anisotropy, but full sampling can then quickly become prohibitively time consuming. However, for incompletely sampled data, compressed sensing is an effective reconstruction technique to enable accelerated acquisition. We demonstrate that with a compressed sensing scheme, one can greatly reduce the sampling and the experimental time with minimal effect on the reconstruction of the diffusion propagator with an example of anisotropic diffusion. We compare full sampling down to 64× sub-sampling for the 2D propagator measurement and reduce the acquisition time for the 3D experiment by a factor of 32 from ∼80 days to ∼2.5 days. PMID:21924932
Multidimensional Extension of the Generalized Chowla-Selberg Formula
NASA Astrophysics Data System (ADS)
Elizalde, E.
After recalling the precise existence conditions of the zeta function of a pseudodifferential operator, and the concept of reflection formula, an exponentially convergent expression for the analytic continuation of a multidimensional inhomogeneous Epstein-type zeta function of the general form
Tissue proteomics using capillary isoelectric focusing-based multidimensional separations.
Wang, Yueju; Balgley, Brian M; Lee, Cheng S
2005-10-01
The capabilities of capillary isoelectric focusing-based multidimensional separations for performing proteome analysis from minute samples create new opportunities in the pursuit of biomarker discovery using enriched and selected cell populations procured from tissue specimens. In this article, recent advances in online integration of capillary isoelectric focusing with nano-reversed phase liquid chromatography for achieving high-resolution peptide and protein separations prior to mass spectrometry analysis are reviewed, along with its potential application to tissue proteomics. These proteome technological advances combined with recently developed tissue microdissection techniques, provide powerful tools for those seeking to gain a greater understanding at the global level of the cellular machinery associated with human diseases such as cancer.
Multidimensional stationary probability distribution for interacting active particles
Maggi, Claudio; Marconi, Umberto Marini Bettolo; Gnan, Nicoletta; Di Leonardo, Roberto
2015-01-01
We derive the stationary probability distribution for a non-equilibrium system composed by an arbitrary number of degrees of freedom that are subject to Gaussian colored noise and a conservative potential. This is based on a multidimensional version of the Unified Colored Noise Approximation. By comparing theory with numerical simulations we demonstrate that the theoretical probability density quantitatively describes the accumulation of active particles around repulsive obstacles. In particular, for two particles with repulsive interactions, the probability of close contact decreases when one of the two particle is pinned. Moreover, in the case of isotropic confining potentials, the radial density profile shows a non trivial scaling with radius. Finally we show that the theory well approximates the “pressure” generated by the active particles allowing to derive an equation of state for a system of non-interacting colored noise-driven particles. PMID:26021260
Wang, Liang; Basarab, Adrian; Girard, Patrick R; Croisille, Pierre; Clarysse, Patrick; Delachartre, Philippe
2015-08-01
Different mathematical tools, such as multidimensional analytic signals, allow for the calculation of 2D spatial phases of real-value images. The motion estimation method proposed in this paper is based on two spatial phases of the 2D analytic signal applied to cardiac sequences. By combining the information of these phases issued from analytic signals of two successive frames, we propose an analytical estimator for 2D local displacements. To improve the accuracy of the motion estimation, a local bilinear deformation model is used within an iterative estimation scheme. The main advantages of our method are: (1) The phase-based method allows the displacement to be estimated with subpixel accuracy and is robust to image intensity variation in time; (2) Preliminary filtering is not required due to the bilinear model. The proposed algorithm, integrating phase-based optical flow motion estimation and the combination of global motion compensation with local bilinear transform, allows spatio-temporal cardiac motion analysis, e.g. strain and dense trajectory estimation over the cardiac cycle. Results from 7 realistic simulated tagged magnetic resonance imaging (MRI) sequences show that our method is more accurate compared with state-of-the-art method for cardiac motion analysis and with another differential approach from the literature. The motion estimation errors (end point error) of the proposed method are reduced by about 33% compared with that of the two methods. In our work, the frame-to-frame displacements are further accumulated in time, to allow for the calculation of myocardial Lagrangian cardiac strains and point trajectories. Indeed, from the estimated trajectories in time on 11 in vivo data sets (9 patients and 2 healthy volunteers), the shape of myocardial point trajectories belonging to pathological regions are clearly reduced in magnitude compared with the ones from normal regions. Myocardial point trajectories, estimated from our phase-based analytic
Wang, Liang; Basarab, Adrian; Girard, Patrick R; Croisille, Pierre; Clarysse, Patrick; Delachartre, Philippe
2015-08-01
Different mathematical tools, such as multidimensional analytic signals, allow for the calculation of 2D spatial phases of real-value images. The motion estimation method proposed in this paper is based on two spatial phases of the 2D analytic signal applied to cardiac sequences. By combining the information of these phases issued from analytic signals of two successive frames, we propose an analytical estimator for 2D local displacements. To improve the accuracy of the motion estimation, a local bilinear deformation model is used within an iterative estimation scheme. The main advantages of our method are: (1) The phase-based method allows the displacement to be estimated with subpixel accuracy and is robust to image intensity variation in time; (2) Preliminary filtering is not required due to the bilinear model. The proposed algorithm, integrating phase-based optical flow motion estimation and the combination of global motion compensation with local bilinear transform, allows spatio-temporal cardiac motion analysis, e.g. strain and dense trajectory estimation over the cardiac cycle. Results from 7 realistic simulated tagged magnetic resonance imaging (MRI) sequences show that our method is more accurate compared with state-of-the-art method for cardiac motion analysis and with another differential approach from the literature. The motion estimation errors (end point error) of the proposed method are reduced by about 33% compared with that of the two methods. In our work, the frame-to-frame displacements are further accumulated in time, to allow for the calculation of myocardial Lagrangian cardiac strains and point trajectories. Indeed, from the estimated trajectories in time on 11 in vivo data sets (9 patients and 2 healthy volunteers), the shape of myocardial point trajectories belonging to pathological regions are clearly reduced in magnitude compared with the ones from normal regions. Myocardial point trajectories, estimated from our phase-based analytic
NASA Technical Reports Server (NTRS)
2007-01-01
This five-frame sequence of New Horizons images captures the giant plume from Io's Tvashtar volcano. Snapped by the probe's Long Range Reconnaissance Imager (LORRI) as the spacecraft flew past Jupiter earlier this year, this first-ever 'movie' of an Io plume clearly shows motion in the cloud of volcanic debris, which extends 330 kilometers (200 miles) above the moon's surface. Only the upper part of the plume is visible from this vantage point -- the plume's source is 130 kilometers (80 miles) below the edge of Io's disk, on the far side of the moon.
The appearance and motion of the plume is remarkably similar to an ornamental fountain on Earth, replicated on a gigantic scale. The knots and filaments that allow us to track the plume's motion are still mysterious, but this movie is likely to help scientists understand their origin, as well as provide unique information on the plume dynamics.
Io's hyperactive nature is emphasized by the fact that two other volcanic plumes are also visible off the edge of Io's disk: Masubi at the 7 o'clock position, and a very faint plume, possibly from the volcano Zal, at the 10 o'clock position. Jupiter illuminates the night side of Io, and the most prominent feature visible on the disk is the dark horseshoe shape of the volcano Loki, likely an enormous lava lake. Boosaule Mons, which at 18 kilometers (11 miles) is the highest mountain on Io and one of the highest mountains in the solar system, pokes above the edge of the disk on the right side.
The five images were obtained over an 8-minute span, with two minutes between frames, from 23:50 to 23:58 Universal Time on March 1, 2007. Io was 3.8 million kilometers (2.4 million miles) from New Horizons; the image is centered at Io coordinates 0 degrees north, 342 degrees west.
The pictures were part of a sequence designed to look at Jupiter's rings, but planners included Io in the sequence because the moon was passing behind Jupiter's rings at the time.
Crump, M. P.; Spyracopoulos, L.; Lavigne, P.; Kim, K. S.; Clark-lewis, I.; Sykes, B. D.
1999-01-01
Eotaxin is a member of the chemokine family of about 40 proteins that induce cell migration. Eotaxin binds the CC chemokine receptor CCR3 that is highly expressed by eosinophils, and it is considered important in the pathology of chronic respiratory disorders such as asthma. The high resolution structure of eotaxin is known. The 74 amino acid protein has two disulfide bridges and shows a typical chemokine fold comprised of a core of three antiparallel beta-strands and an overlying alpha-helix. In this paper, we report the backbone dynamics of eotaxin determined through 15N-T1, T2, and [1H]-15N nuclear Overhauser effect heteronuclear multidimensional NMR experiments. This is the first extensive study of the dynamics of a chemokine derived from 600, 500, and 300 MHz NMR field strengths. From the T1, T2, and NOE relaxation data, parameters that describe the internal motions of eotaxin were derived using the Lipari-Szabo model free analysis. The most ordered regions of the protein correspond to the known secondary structure elements. However, surrounding the core, the regions known to be functionally important in chemokines show a range of motions on varying timescales. These include extensive subnanosecond to picosecond motions in the N-terminus, C-terminus, and the N-loop succeeding the disulfides. Analysis of rotational diffusion anisotropy of eotaxin and chemical exchange terms at multiple fields also allowed the confident identification of slow conformational exchange through the "30s" loop, disulfides, and adjacent residues. In addition, we show that these motions may be attenuated in the dimeric form of a synthetic eotaxin. The structure and dynamical basis for eotaxin receptor binding is discussed in light of the dynamics data. PMID:10548050
Representations of motion and direction.
Price, C M; Gilden, D L
2000-02-01
In 6 experiments, incidental memory was tested for direction of motion in an old-new recognition paradigm. Ability to recognize previously shown directions depended greatly on motion type. Memory for translation and expansion-contraction direction was highly veridical, whereas memory for rotation direction was conspicuously absent. Similar results were obtained in conditions in which motions were illustrated with pictures. Results suggest that explicit representations of direction in long-term memory are not so much related to motion per se as to the consequences of motion, the displacements of objects. Memory for all motions following circular pathways was found to be corrupted by a generic bias to regard the clockwise direction as familiar. Assessment of memory in these cases required disentangling familiarity bias for the clockwise direction from explicit recognition of direction.
Delusions in Patients with Alzheimer's Disease: A Multidimensional Approach.
D'Onofrio, Grazia; Panza, Francesco; Sancarlo, Daniele; Paris, Francesco F; Cascavilla, Leandro; Mangiacotti, Antonio; Lauriola, Michele; Paroni, Giulia H; Seripa, Davide; Greco, Antonio
2016-01-01
In Alzheimer's disease (AD) patients with delusions, clinical outcomes and mortality result from a combination of psychological, biological, functional, and environmental factors. We determined the effect of delusions on mortality risk, clinical outcomes linked to comprehensive geriatric assessment (CGA), cognitive, depressive, and neuropsychiatric symptoms (NPS) in 380 consecutive AD patients with Mini-Mental State Examination, Clinical Dementia Rating scale, 15-item Geriatric Depression Scale, and Neuropsychiatric Inventory (NPI), assessing one-year mortality risk using the Multidimensional Prognostic Index (MPI). We included 121 AD patients with delusions (AD-D) and 259 AD patients without delusions (AD-noD). AD-D patients were significantly older, with higher age at onset and cognitive impairment, a more severe stage of dementia, and more depressive symptoms than AD-noD patients. Disease duration was slightly higher in AD-D patients than in those without delusions, although this difference was not statistically significant. At CGA, AD-D patients showed a higher grade of disability in basic and instrumental activities of daily living, and an increased risk of malnutrition and bedsores. The two groups of patients significantly differed in MPI score (AD-D: 0.65 versus AD-noD: 0.51, p < 0.0001) and MPI grade. AD-D patients showed also a significant higher score in NPI of the following NPS than AD-noD patients: hallucinations, agitation/aggression, depression mood, apathy, irritability/lability, aberrant motor activity, sleep disturbances, and eating disorders. Therefore, AD-D patients showed higher dementia severity, and higher impairment in cognitive and depressive symptoms, and several neuropsychiatric domains than AD-noD patients, and this appeared to be associated with higher multidimensional impairment and increased risk of mortality. PMID:26890768
Multidimensional optimal droop control for wind resources in DC microgrids
NASA Astrophysics Data System (ADS)
Bunker, Kaitlyn J.
Two important and upcoming technologies, microgrids and electricity generation from wind resources, are increasingly being combined. Various control strategies can be implemented, and droop control provides a simple option without requiring communication between microgrid components. Eliminating the single source of potential failure around the communication system is especially important in remote, islanded microgrids, which are considered in this work. However, traditional droop control does not allow the microgrid to utilize much of the power available from the wind. This dissertation presents a novel droop control strategy, which implements a droop surface in higher dimension than the traditional strategy. The droop control relationship then depends on two variables: the dc microgrid bus voltage, and the wind speed at the current time. An approach for optimizing this droop control surface in order to meet a given objective, for example utilizing all of the power available from a wind resource, is proposed and demonstrated. Various cases are used to test the proposed optimal high dimension droop control method, and demonstrate its function. First, the use of linear multidimensional droop control without optimization is demonstrated through simulation. Next, an optimal high dimension droop control surface is implemented with a simple dc microgrid containing two sources and one load. Various cases for changing load and wind speed are investigated using simulation and hardware-in-the-loop techniques. Optimal multidimensional droop control is demonstrated with a wind resource in a full dc microgrid example, containing an energy storage device as well as multiple sources and loads. Finally, the optimal high dimension droop control method is applied with a solar resource, and using a load model developed for a military patrol base application. The operation of the proposed control is again investigated using simulation and hardware-in-the-loop techniques.
Relevance in the science classroom: A multidimensional analysis
NASA Astrophysics Data System (ADS)
Hartwell, Matthew F.
While perceived relevance is considered a fundamental component of adaptive learning, the experience of relevance and its conceptual definition have not been well described. The mixed-methods research presented in this dissertation aimed to clarify the conceptual meaning of relevance by focusing on its phenomenological experience from the students' perspective. Following a critical literature review, I propose an identity-based model of perceived relevance that includes three components: a contextual target, an identity target, and a connection type, or lens. An empirical investigation of this model that consisted of two general phases was implemented in four 9th grade-biology classrooms. Participants in Phase 1 (N = 118) completed a series of four open-ended writing activities focused on eliciting perceived personal connections to academic content. Exploratory qualitative content analysis of a 25% random sample of the student responses was used to identify the main meaning-units of the proposed model as well as different dimensions of student relevance perceptions. These meaning-units and dimensions provided the basis for the construction of a conceptual mapping sentence capturing students' perceived relevance, which was then applied in a confirmatory analysis to all other student responses. Participants in Phase 2 (N = 139) completed a closed survey designed based on the mapping sentence to assess their perceived relevance of a biology unit. The survey also included scales assessing other domain-level motivational processes. Exploratory factor analysis and non-metric multidimensional scaling indicated a coherent conceptual structure, which included a primary interpretive relevance dimension. Comparison of the conceptual structure across various groups (randomly-split sample, gender, academic level, domain-general motivational profiles) provided support for its ubiquity and insight into variation in the experience of perceived relevance among students of different
Statistical Downscaling in Multi-dimensional Wave Climate Forecast
NASA Astrophysics Data System (ADS)
Camus, P.; Méndez, F. J.; Medina, R.; Losada, I. J.; Cofiño, A. S.; Gutiérrez, J. M.
2009-04-01
Wave climate at a particular site is defined by the statistical distribution of sea state parameters, such as significant wave height, mean wave period, mean wave direction, wind velocity, wind direction and storm surge. Nowadays, long-term time series of these parameters are available from reanalysis databases obtained by numerical models. The Self-Organizing Map (SOM) technique is applied to characterize multi-dimensional wave climate, obtaining the relevant "wave types" spanning the historical variability. This technique summarizes multi-dimension of wave climate in terms of a set of clusters projected in low-dimensional lattice with a spatial organization, providing Probability Density Functions (PDFs) on the lattice. On the other hand, wind and storm surge depend on instantaneous local large-scale sea level pressure (SLP) fields while waves depend on the recent history of these fields (say, 1 to 5 days). Thus, these variables are associated with large-scale atmospheric circulation patterns. In this work, a nearest-neighbors analog method is used to predict monthly multi-dimensional wave climate. This method establishes relationships between the large-scale atmospheric circulation patterns from numerical models (SLP fields as predictors) with local wave databases of observations (monthly wave climate SOM PDFs as predictand) to set up statistical models. A wave reanalysis database, developed by Puertos del Estado (Ministerio de Fomento), is considered as historical time series of local variables. The simultaneous SLP fields calculated by NCEP atmospheric reanalysis are used as predictors. Several applications with different size of sea level pressure grid and with different temporal domain resolution are compared to obtain the optimal statistical model that better represents the monthly wave climate at a particular site. In this work we examine the potential skill of this downscaling approach considering perfect-model conditions, but we will also analyze the
Describing temperament in an ungulate: a multidimensional approach.
Graunke, Katharina L; Nürnberg, Gerd; Repsilber, Dirk; Puppe, Birger; Langbein, Jan
2013-01-01
Studies on animal temperament have often described temperament using a one-dimensional scale, whereas theoretical framework has recently suggested two or more dimensions using terms like "valence" or "arousal" to describe these dimensions. Yet, the valence or assessment of a situation is highly individual. The aim of this study was to provide support for the multidimensional framework with experimental data originating from an economically important species (Bos taurus). We tested 361 calves at 90 days post natum (dpn) in a novel-object test. Using a principal component analysis (PCA), we condensed numerous behaviours into fewer variables to describe temperament and correlated these variables with simultaneously measured heart rate variability (HRV) data. The PCA resulted in two behavioural dimensions (principal components, PC): novel-object-related (PC 1) and exploration-activity-related (PC 2). These PCs explained 58% of the variability in our data. The animals were distributed evenly within the two behavioural dimensions independent of their sex. Calves with different scores in these PCs differed significantly in HRV, and thus in the autonomous nervous system's activity. Based on these combined behavioural and physiological data we described four distinct temperament types resulting from two behavioural dimensions: "neophobic/fearful--alert", "interested--stressed", "subdued/uninterested--calm", and "neoophilic/outgoing--alert". Additionally, 38 calves were tested at 90 and 197 dpn. Using the same PCA-model, they correlated significantly in PC 1 and tended to correlate in PC 2 between the two test ages. Of these calves, 42% expressed a similar behaviour pattern in both dimensions and 47% in one. No differences in temperament scores were found between sexes or breeds. In conclusion, we described distinct temperament types in calves based on behavioural and physiological measures emphasising the benefits of a multidimensional approach.
Continuously tunable optical multidimensional Fourier-transform spectrometer.
Dey, P; Paul, J; Bylsma, J; Deminico, S; Karaiskaj, D
2013-02-01
A multidimensional optical nonlinear spectrometer (MONSTR) is a robust, ultrastable platform consisting of nested and folded Michelson interferometers that can be actively phase stabilized. The MONSTR provides output pulses for nonlinear excitation of materials and phase-stabilized reference pulses for heterodyne detection of the induced signal. This platform generates a square of identical laser pulses that can be adjusted to have arbitrary time delays between them while maintaining phase stability. This arrangement is ideal for performing coherent optical experiments, such as multidimensional Fourier-transform spectroscopy. The present work reports on overcoming some important limitations on the original design of the MONSTR apparatus. One important advantage of the MONSTR is the fact that it is a closed platform, which provides the high stability. Once the optical alignment is performed, it is desirable to maintain the alignment over long periods of time. The previous design of the MONSTR was limited to a narrow spectral range defined by the optical coating of the beam splitters. In order to achieve tunability over a broad spectral range the internal optics needed to be changed. By using broadband coated and wedged beam splitters and compensator plates, combined with modifications of the beam paths, continuous tunability can be achieved from 520 nm to 1100 nm without changing any optics or performing alignment of the internal components of the MONSTR. Furthermore, in order to achieve continuous tunability in the spectral region between 520 nm and 720 nm, crucially important for studies on numerous biological molecules, a single longitudinal mode laser at 488.5 nm was identified and used as a metrology laser. The shorter wavelength of the metrology laser as compared to the usual HeNe laser has also increased the phase stability of the system. Finally, in order to perform experiments in the reflection geometry, a simple method to achieve active phase stabilization
Response inhibition and its relation to multidimensional impulsivity.
Wilbertz, Tilmann; Deserno, Lorenz; Horstmann, Annette; Neumann, Jane; Villringer, Arno; Heinze, Hans-Jochen; Boehler, Carsten N; Schlagenhauf, Florian
2014-12-01
Impulsivity is a multidimensional construct that has been suggested as a vulnerability factor for several psychiatric disorders, especially addiction disorders. Poor response inhibition may constitute one facet of impulsivity. Trait impulsivity can be assessed by self-report questionnaires such as the widely used Barratt Impulsiveness Scale (BIS-11). However, regarding the multidimensionality of impulsivity different concepts have been proposed, in particular the UPPS self-report questionnaire ('Urgency', 'Lack of Premeditation', 'Lack of Perseverance', 'Sensation Seeking') that is based on a factor analytic approach. The question as to which aspects of trait impulsivity map on individual differences of the behavioral and neural correlates of response inhibition so far remains unclear. In the present study, we investigated 52 healthy individuals that scored either very high or low on the BIS-11 and underwent a reward-modulated Stop-signal task during fMRI. Neither behavioral nor neural differences were observed with respect to high- and low-BIS groups. In contrast, UPPS subdomain Urgency best explained inter-individual variability in SSRT scores and was further negatively correlated to right IFG/aI activation in 'Stop>Go' trials - a key region for response inhibition. Successful response inhibition in rewarded compared to nonrewarded stop trials yielded ventral striatal (VS) activation which might represent a feedback signal. Interestingly, only participants with low Urgency scores were able to use this VS feedback signal for better response inhibition. Our findings indicate that the relationship of impulsivity and response inhibition has to be treated carefully. We propose Urgency as an important subdomain that might be linked to response inhibition as well as to the use of reward-based neural signals. Based on the present results, further studies examining the influence of impulsivity on psychiatric disorders should take into account Urgency as an important
Managing space motion sickness.
Jennings, R T
1998-01-01
Space motion sickness is a well-recognized problem for space flight and affects 73% of crewmembers on the first 2 or 3 days of their initial flight. Illness severity is variable, but over half of cases are categorized as moderate to severe. Management has included elimination of provocative activities and delay of critical performance-related procedures such as extra-vehicular activity (EVA) or Shuttle landing during the first three days of missions. Pharmacological treatment strategies have had variable results, but intramuscular promethazine has been the most effective to date with a 90% initial response rate and important reduction in residual symptoms the next flight day. Oral prophylactic treatment of crewmembers with difficulty on prior flights has had mixed results. In order to accommodate more aggressive pharmacologic management, crew medical officers receive additional training in parenteral administration of medications. Preflight medication testing is accomplished to reduce the risk of unexpected performance decrements or idiosyncratic reactions. When possible, treatment is offered in the presleep period to mask potential treatment-related drowsiness. Another phenomenon noted by crewmembers and physicians as flights have lengthened is readaptation difficulty or motion sickness on return to Earth. These problems have included nausea, vomiting, and difficulty with locomotion or coordination upon early exposure to gravity. Since landing and egress are principal concerns during this portion of the flight, these deficits are of operational concern. Postflight therapy has been directed at nausea and vomiting, and meclizine and promethazine are the principal agents used. There has been no official attempt at prophylactic treatment prior to entry. Since there is considerable individual variation in postflight deficit and since adaptation from prior flights seems to persist, it has been recommended that commanders with prior shuttle landing experience be named to
Multivariate respiratory motion prediction
NASA Astrophysics Data System (ADS)
Dürichen, R.; Wissel, T.; Ernst, F.; Schlaefer, A.; Schweikard, A.
2014-10-01
In extracranial robotic radiotherapy, tumour motion is compensated by tracking external and internal surrogates. To compensate system specific time delays, time series prediction of the external optical surrogates is used. We investigate whether the prediction accuracy can be increased by expanding the current clinical setup by an accelerometer, a strain belt and a flow sensor. Four previously published prediction algorithms are adapted to multivariate inputs—normalized least mean squares (nLMS), wavelet-based least mean squares (wLMS), support vector regression (SVR) and relevance vector machines (RVM)—and evaluated for three different prediction horizons. The measurement involves 18 subjects and consists of two phases, focusing on long term trends (M1) and breathing artefacts (M2). To select the most relevant and least redundant sensors, a sequential forward selection (SFS) method is proposed. Using a multivariate setting, the results show that the clinically used nLMS algorithm is susceptible to large outliers. In the case of irregular breathing (M2), the mean root mean square error (RMSE) of a univariate nLMS algorithm is 0.66 mm and can be decreased to 0.46 mm by a multivariate RVM model (best algorithm on average). To investigate the full potential of this approach, the optimal sensor combination was also estimated on the complete test set. The results indicate that a further decrease in RMSE is possible for RVM (to 0.42 mm). This motivates further research about sensor selection methods. Besides the optical surrogates, the sensors most frequently selected by the algorithms are the accelerometer and the strain belt. These sensors could be easily integrated in the current clinical setup and would allow a more precise motion compensation.
Earthquake ground motion: Chapter 3
Luco, Nicolas; Valley, Michael; Crouse, C.B.
2012-01-01
Most of the effort in seismic design of buildings and other structures is focused on structural design. This chapter addresses another key aspect of the design process—characterization of earthquake ground motion. Section 3.1 describes the basis of the earthquake ground motion maps in the Provisions and in ASCE 7. Section 3.2 has examples for the determination of ground motion parameters and spectra for use in design. Section 3.3 discusses and provides an example for the selection and scaling of ground motion records for use in response history analysis.
GPR image signal enhancement and feature extraction using contemporary multidimensional EMD methods
NASA Astrophysics Data System (ADS)
Jeng, Yih; Chen, Chih-Sung
2016-04-01
Although the empirical mode decomposition (EMD) method has been introduced to the geophysical community for more than one decade, most applications are limited to one dimensional (1D) time series analysis or the likes. However, the EMD has long been prone to multidimensional, and the algorithm has been renovated from pseudo type to real multidimensional. There are two parallel novel multidimensional algorithms have been proposed in recent years, i.e. the multidimensional ensemble empirical mode decomposition (MEEMD or MDEEMD) and the multivariate empirical mode decomposition (MEMD). Probably due to the complexity of algorithms and high computation cost, these two multidimensional EMD methods are very little employed to process geophysical data. In this study, we mainly apply the MEMD to the ground penetrating radar (GPR) data processing which, to the best of authors' knowledge, hasn't been done before. The MEMD determines the multidimensional envelopes by projecting data on hyperspheres which extends the 1D algorithm to multidimensional, and the extrema of the data are determined by considering the data in all directions consequently. This renovation technique improves the alignment of intrinsic mode functions (IMFs) and reduces the mode mixing and aliasing problems of the EMD. We demonstrate this method using GPR field data acquired from an area of poor reflection quality. Some modifications of the computation procedures are made to facilitate the application of this approach in the geophysical data processing. To evaluate the success of this approach, MDEEMD results are also presented for comparison.
Motion parallax links visual motion areas and scene regions.
Schindler, Andreas; Bartels, Andreas
2016-01-15
When we move, the retinal velocities of objects in our surrounding differ according to their relative distances and give rise to a powerful three-dimensional visual cue referred to as motion parallax. Motion parallax allows us to infer our surrounding's 3D structure as well as self-motion based on 2D retinal information. However, the neural substrates mediating the link between visual motion and scene processing are largely unexplored. We used fMRI in human observers to study motion parallax by means of an ecologically relevant yet highly controlled stimulus that mimicked the observer's lateral motion past a depth-layered scene. We found parallax selective responses in parietal regions IPS3 and IPS4, and in a region lateral to scene selective occipital place area (OPA). The traditionally defined scene responsive regions OPA, the para-hippocampal place area (PPA) and the retrosplenial cortex (RSC) did not respond to parallax. During parallax processing, the occipital parallax selective region entertained highly specific functional connectivity with IPS3 and with scene selective PPA. These results establish a network linking dorsal motion and ventral scene processing regions specifically during parallax processing, which may underlie the brain's ability to derive 3D scene information from motion parallax. PMID:26515906
Motion-Matching: A Challenge Game to Generate Motion Concepts
ERIC Educational Resources Information Center
Schuster, David; Adams, Betty; Brookes, David; Milner-Bolotin, Marina; Undreiu, Adriana
2009-01-01
Motion is a topic that is taught from elementary grades through to university at various levels of sophistication. It is an area that can be challenging for learning in a conceptually meaningful way, and formal kinematics instruction can sometimes seem dry and boring. Thus, the nature of students' initial introduction to motion is important in…
Fast motion deblurring using sensor-aided motion trajectory estimation.
Lee, Eunsung; Chae, Eunjung; Cheong, Hejin; Paik, Joonki
2014-01-01
This paper presents an image deblurring algorithm to remove motion blur using analysis of motion trajectories and local statistics based on inertial sensors. The proposed method estimates a point-spread-function (PSF) of motion blur by accumulating reweighted projections of the trajectory. A motion blurred image is then adaptively restored using the estimated PSF and spatially varying activity map to reduce both restoration artifacts and noise amplification. Experimental results demonstrate that the proposed method outperforms existing PSF estimation-based motion deconvolution methods in the sense of both objective and subjective performance measures. The proposed algorithm can be employed in various imaging devices because of its efficient implementation without an iterative computational structure.
A log-linear multidimensional Rasch model for capture-recapture.
Pelle, E; Hessen, D J; van der Heijden, P G M
2016-02-20
In this paper, a log-linear multidimensional Rasch model is proposed for capture-recapture analysis of registration data. In the model, heterogeneity of capture probabilities is taken into account, and registrations are viewed as dichotomously scored indicators of one or more latent variables that can account for correlations among registrations. It is shown how the probability of a generic capture profile is expressed under the log-linear multidimensional Rasch model and how the parameters of the traditional log-linear model are derived from those of the log-linear multidimensional Rasch model. Finally, an application of the model to neural tube defects data is presented.
Accessing Multi-Dimensional Images and Data Cubes in the Virtual Observatory
NASA Astrophysics Data System (ADS)
Tody, Douglas; Plante, R. L.; Berriman, G. B.; Cresitello-Dittmar, M.; Good, J.; Graham, M.; Greene, G.; Hanisch, R. J.; Jenness, T.; Lazio, J.; Norris, P.; Pevunova, O.; Rots, A. H.
2014-01-01
Telescopes across the spectrum are routinely producing multi-dimensional images and datasets, such as Doppler velocity cubes, polarization datasets, and time-resolved “movies.” Examples of current telescopes producing such multi-dimensional images include the JVLA, ALMA, and the IFU instruments on large optical and near-infrared wavelength telescopes. In the near future, both the LSST and JWST will also produce such multi-dimensional images routinely. High-energy instruments such as Chandra produce event datasets that are also a form of multi-dimensional data, in effect being a very sparse multi-dimensional image. Ensuring that the data sets produced by these telescopes can be both discovered and accessed by the community is essential and is part of the mission of the Virtual Observatory (VO). The Virtual Astronomical Observatory (VAO, http://www.usvao.org/), in conjunction with its international partners in the International Virtual Observatory Alliance (IVOA), has developed a protocol and an initial demonstration service designed for the publication, discovery, and access of arbitrarily large multi-dimensional images. The protocol describing multi-dimensional images is the Simple Image Access Protocol, version 2, which provides the minimal set of metadata required to characterize a multi-dimensional image for its discovery and access. A companion Image Data Model formally defines the semantics and structure of multi-dimensional images independently of how they are serialized, while providing capabilities such as support for sparse data that are essential to deal effectively with large cubes. A prototype data access service has been deployed and tested, using a suite of multi-dimensional images from a variety of telescopes. The prototype has demonstrated the capability to discover and remotely access multi-dimensional data via standard VO protocols. The prototype informs the specification of a protocol that will be submitted to the IVOA for approval, with an
Chubb, C; McGowan, J; Sperling, G; Werkhoven, P
1994-01-01
It has been realized for some time that the visual system performs at least two general sorts of motion processing. First-order motion processing applies some variant of standard motion analysis (i.e. spatiotemporal Fourier energy analysis) directly to stimulus luminance, whereas second-order motion processing applies standard motion analysis to one or another grossly non-linear transformation of stimulus luminance. We have developed a method for disentangling the different sorts of mechanisms that may operate in human vision to detect second-order motion. This method hinges on an empirical condition called transition invariance that may or may not be satisfied by a family psi of textures. Any failure of this condition indicates that more than one mechanism is involved in detecting the motion of stimuli composed of the textures in psi. We have shown that the family of sinusoidal gratings oriented orthogonally to the direction of motion and varying in contrast and spatial frequency is transition invariant. We modelled the results in terms of a single-channel motion computation. We have new results indicating that a specific class of textures differing in texture element density and texture element contrast decisively fails the test of transition invariance. These findings suggest that in addition to the single second-order motion channel required by our earlier results there exists at least one other second-order motion channel. We argue that the preprocessing transformation used by this channel is a pointwise non-linearity that maps stimulus contrasts of absolute value less than some relatively high threshold tau onto 0, but increases with magnitude of c-tau for contrasts. c of absolute value greater than tau.
Topographic Structure from Motion
NASA Astrophysics Data System (ADS)
Fonstad, M. A.; Dietrich, J. T.; Courville, B. C.; Jensen, J.; Carbonneau, P.
2011-12-01
The production of high-resolution topographic datasets is of increasing concern and application throughout the geomorphic sciences, and river science is no exception. Consequently, a wide range of topographic measurement methods have evolved. Despite the range of available methods, the production of high resolution, high quality digital elevation models (DEMs) generally requires a significant investment in personnel time, hardware and/or software. However, image-based methods such as digital photogrammetry have steadily been decreasing in costs. Initially developed for the purpose of rapid, inexpensive and easy three dimensional surveys of buildings or small objects, the "structure from motion" photogrammetric approach (SfM) is a purely image based method which could deliver a step-change if transferred to river remote sensing, and requires very little training and is extremely inexpensive. Using the online SfM program Microsoft Photosynth, we have created high-resolution digital elevation models (DEM) of rivers from ordinary photographs produced from a multi-step workflow that takes advantage of free and open source software. This process reconstructs real world scenes from SfM algorithms based on the derived positions of the photographs in three-dimensional space. One of the products of the SfM process is a three-dimensional point cloud of features present in the input photographs. This point cloud can be georeferenced from a small number of ground control points collected via GPS in the field. The georeferenced point cloud can then be used to create a variety of digital elevation model products. Among several study sites, we examine the applicability of SfM in the Pedernales River in Texas (USA), where several hundred images taken from a hand-held helikite are used to produce DEMs of the fluvial topographic environment. This test shows that SfM and low-altitude platforms can produce point clouds with point densities considerably better than airborne LiDAR, with
Motion perception under mesopic vision.
Yoshimoto, Sanae; Okajima, Katsunori; Takeuchi, Tatsuto
2016-01-01
Mesopic and scotopic vision extend over an illuminance range of 106. The goal of the present study was to determine the effect of decreasing light level on the underlying motion mechanism that integrates spatiotemporally separated motion signals. To accomplish this, we took advantage of the phenomenon of visual motion priming, in which the perceived direction of a directionally ambiguous test stimulus is influenced by the directional movement of a preceding priming stimulus. After terminating a drifting priming stimulus, a 180° phase-shifted grating was presented as a test stimulus. The priming and test stimuli were separately presented to the central and peripheral retinas, respectively. The participants judged the perceived direction of this test stimulus at various light levels from photopic to scotopic levels. We found that the effects of motion priming disappeared over 1 log unit of mesopic light levels. When the test stimulus was presented before the offset of the priming stimulus to compensate for the temporal delay in the rod pathway or when both stimuli were presented at the same location in the periphery, a motion-priming effect appeared at mesopic light levels. These results suggest that different temporal characteristics between the cone pathway and rod pathway disturb the function of the putative motion mechanism responsible for the spatiotemporal integration of motion signals, which leads to specific modulation of motion perception over a wide range of mesopic vision. PMID:26818969
An open architecture motion controller
NASA Technical Reports Server (NTRS)
Rossol, Lothar
1994-01-01
Nomad, an open architecture motion controller, is described. It is formed by a combination of TMOS, C-WORKS, and other utilities. Nomad software runs in a UNIX environment and provides for sensor-controlled robotic motions, with user replaceable kinematics. It can also be tailored for highly specialized applications. Open controllers such as Nomad should have a major impact on the robotics industry.
The Perception of Auditory Motion
Leung, Johahn
2016-01-01
The growing availability of efficient and relatively inexpensive virtual auditory display technology has provided new research platforms to explore the perception of auditory motion. At the same time, deployment of these technologies in command and control as well as in entertainment roles is generating an increasing need to better understand the complex processes underlying auditory motion perception. This is a particularly challenging processing feat because it involves the rapid deconvolution of the relative change in the locations of sound sources produced by rotational and translations of the head in space (self-motion) to enable the perception of actual source motion. The fact that we perceive our auditory world to be stable despite almost continual movement of the head demonstrates the efficiency and effectiveness of this process. This review examines the acoustical basis of auditory motion perception and a wide range of psychophysical, electrophysiological, and cortical imaging studies that have probed the limits and possible mechanisms underlying this perception. PMID:27094029
Crowding of biological motion stimuli.
Ikeda, Hanako; Watanabe, Katsumi; Cavanagh, Patrick
2013-01-01
It is difficult to identify a target in the peripheral visual field when it is flanked by distractors. In the present study, we investigated this "crowding" effect for biological motion stimuli. Three walking biological motion stimuli were presented horizontally in the periphery with various distances between them, and observers reported the walking direction of the central figure. When the inter-walker distance was small, discriminating the direction became difficult. Moreover, the reported direction for the central target was not simply noisier, but reflected a degree of pooling of the three directions from the target and two flankers. However, when the two flanking distractors were scrambled walking biological motion stimuli, crowding was not seen. This result suggests that the crowding of biological motion stimuli occurs at a high-level of motion perception.
Motion blur detection in radiographs
NASA Astrophysics Data System (ADS)
Luo, Hui; Sehnert, William J.; Ellinwood, Jacquelyn S.; Foos, David; Reiner, Bruce; Siegel, Eliot
2008-03-01
Image blur introduced by patient motion is one of the most frequently cited reasons for image rejection in radiographic diagnostic imaging. The goal of the present work is to provide an automated method for the detection of anatomical motion blur in digital radiographic images to help improve image quality and facilitate workflow in the radiology department. To achieve this goal, the method first reorients the image to a predetermined hanging protocol. Then it locates the primary anatomy in the radiograph and extracts the most indicative region for motion blur, i.e., the region of interest (ROI). The third step computes a set of motion-sensitive features from the extracted ROI. Finally, the extracted features are evaluated by using a classifier that has been trained to detect motion blur. Preliminary experiments show promising results with 86% detection sensitivity, 72% specificity, and an overall accuracy of 76%.
Forces in rotary motion systems
NASA Astrophysics Data System (ADS)
Tilsch, Markus K.; Elliott, Gregory K.
2008-09-01
In many coating chambers substrates are moved by simple or planetary rotary motion systems. Isaac Newton already taught that an object in uniform motion tends to stay in uniform motion unless acted upon by a net external force. To move a substrate on a rotary trajectory, centripetal and gravitational forces must act upon the substrate. The substrate must be somehow confined. Confinement options range from firm attachment to a fixture to loose placement in a pocket. Depending on the rotary motion pattern, a loosely held substrate may slide once against a confinement boundary and then stay, or may constantly slide around. 'Rattling around' may be undesirable as it could lead to edge destruction, debris formation, precession of the substrate, and other adverse effects. Firm attachment is advantageous in most cases, but often adds process complexity. We examine the forces present on substrates in typical rotary motion systems and discuss the implications of different confinement methods.
The Equations of Oceanic Motions
NASA Astrophysics Data System (ADS)
Müller, Peter
2006-10-01
Modeling and prediction of oceanographic phenomena and climate is based on the integration of dynamic equations. The Equations of Oceanic Motions derives and systematically classifies the most common dynamic equations used in physical oceanography, from large scale thermohaline circulations to those governing small scale motions and turbulence. After establishing the basic dynamical equations that describe all oceanic motions, M|ller then derives approximate equations, emphasizing the assumptions made and physical processes eliminated. He distinguishes between geometric, thermodynamic and dynamic approximations and between the acoustic, gravity, vortical and temperature-salinity modes of motion. Basic concepts and formulae of equilibrium thermodynamics, vector and tensor calculus, curvilinear coordinate systems, and the kinematics of fluid motion and wave propagation are covered in appendices. Providing the basic theoretical background for graduate students and researchers of physical oceanography and climate science, this book will serve as both a comprehensive text and an essential reference.
Nanoparticle mediated micromotor motion.
Liu, Mei; Liu, Limei; Gao, Wenlong; Su, Miaoda; Ge, Ya; Shi, Lili; Zhang, Hui; Dong, Bin; Li, Christopher Y
2015-03-21
In this paper, we report the utilization of nanoparticles to mediate the motion of a polymer single crystal catalytic micromotor. Micromotors have been fabricated by directly self-assembling functional nanoparticles (platinum and iron oxide nanoparticles) onto one or both sides of two-dimensional polymer single crystals. We show that the moving velocity of these micromotors in fluids can be readily tuned by controlling the nanoparticles' surface wettability and catalytic activity. A 3 times velocity increase has been achieved for a hydrophobic micromotor as opposed to the hydrophilic ones. Furthermore, we demonstrate that the catalytic activity of platinum nanoparticles inside the micromotor can be enhanced by their synergetic interactions with iron oxide nanoparticles and an electric field. Both strategies lead to dramatically increased moving velocities, with the highest value reaching ∼200 μm s(-1). By decreasing the nanoparticles' surface wettability and increasing their catalytic activity, a maximum of a ∼10-fold increase in the moving speed of the nanoparticle based micromotor can be achieved. Our results demonstrate the advantages of using nanoparticles in micromotor systems.
NASA Astrophysics Data System (ADS)
Metzler, R.; Sanders, L.; Lomholt, M. A.; Lizana, L.; Fogelmark, K.; Ambjörnsson, Tobias
2014-12-01
The mean squared displacement of a tracer particle in a single file of identical particles with excluded volume interactions shows the famed Harris scaling
Motion words selectively modulate direction discrimination sensitivity for threshold motion
Pavan, Andrea; Skujevskis, Māris; Baggio, Giosuè
2013-01-01
Can speech selectively modulate the sensitivity of a sensory system so that, in the presence of a suitable linguistic context, the discrimination of certain perceptual features becomes more or less likely? In this study, participants heard upward or downward motion words followed by a single visual field of random dots moving upwards or downwards. The time interval between the onsets of the auditory and the visual stimuli was varied parametrically. Motion direction could be either discriminable (suprathreshold motion) or non-discriminable (threshold motion). Participants had to judge whether the dots were moving upward or downward. Results show a double dissociation between discrimination sensitivity (d′) and reaction times depending on whether vertical motion was above or at threshold. With suprathreshold motion, responses were faster for congruent directions of words and dots, but sensitivity was equal across conditions. With threshold motion, sensitivity was higher for congruent directions of words and dots, but responses were equally fast across conditions. The observed differences in sensitivity and response times were largest when the dots appeared 450 ms after word onset, that is, consistently with electrophysiology, at the time the up/down semantics of the word had become available. These data suggest that word meanings can alter the balance between signal and noise within the visual system and affect the perception of low-level sensory features. PMID:23596407
Testing the multidimensionality of the inventory of school motivation in a Dutch student sample.
Korpershoek, Hanke; Xu, Kun; Mok, Magdalena Mo Ching; McInerney, Dennis M; van der Werf, Greetje
2015-01-01
A factor analytic and a Rasch measurement approach were applied to evaluate the multidimensional nature of the school motivation construct among more than 7,000 Dutch secondary school students. The Inventory of School Motivation (McInerney and Ali, 2006) was used, which intends to measure four motivation dimensions (mastery, performance, social, and extrinsic motivation), each comprising of two first-order factors. One unidimensional model and three multidimensional models (4-factor, 8-factor, higher order) were fit to the data. Results of both approaches showed that the multidimensional models validly represented the school motivation among Dutch secondary school pupils, whereas model fit of the unidimensional model was poor. The differences in model fit between the three multidimensional models were small, although a different model was favoured by the two approaches. The need for improvement of some of the items and the need to increase measurement precision of several first-order factors are discussed. PMID:25562335
ERIC Educational Resources Information Center
Dori, Yehudit J.; Hameiri, Mira
1998-01-01
Details the development of a multidimensional problem analysis, classification, and authoring method used to improve student understanding of the mole concept. Includes the results of assessment of the studyware. Contains 46 references. (DDR)
ERIC Educational Resources Information Center
Whitehead, James R.; Corbin, Charles B.
1988-01-01
Trial administrations of the FITLOC, multidimensional scales for the measurement of locus of control of reinforcement for physical fitness behavior, provided preliminary evidence for the scales' reliability and validity. (Author/CB)
ERIC Educational Resources Information Center
Redfield, Joel
1978-01-01
TMFA, a FORTRAN program for three-mode factor analysis and individual-differences multidimensional scaling, is described. Program features include a variety of input options, extensive preprocessing of input data, and several alternative methods of analysis. (Author)
ERIC Educational Resources Information Center
Kim, Chulwan; Rangaswamy, Arvind; DeSarbo, Wayne S.
1999-01-01
Presents an approach to multidimensional unfolding that reduces the occurrence of degenerate solutions and conducts a Monte Carlo study to demonstrate the superiority of the new method to the ALSCAL and KYST nonmetric procedures for student preference data. (SLD)
Stump, B.W.; Anderson, D.P.
1995-04-01
Constraint of the operative physical processes in the source region of mining explosions and the linkage to the generation of seismic waveforms provides the opportunity for controlling ground motion. Development of these physical models can also be used in conjunction with the ground motion data as diagnostics of blasting efficiency. In order to properly address the multi-dimensional aspect of data sets designed to constrain these sources, we are investigating a number of modem visualization tools that have only recently become available with new, high-speed graphical computers that can utilize relatively large data sets. The data sets that are combined in the study of mining explosion sources include near-source ground motion acceleration and velocity records, velocity of detonation measurements in each explosive hole, high speed film, video and shot design information.
Code of Federal Regulations, 2014 CFR
2014-04-01
... 22 Foreign Relations 2 2014-04-01 2014-04-01 false Motions. 1423.22 Section 1423.22 Foreign... PROCEEDINGS § 1423.22 Motions. (a) Filing of Motions. (1) Motions made prior to a hearing and any response... issuance of a complaint by the Regional Director any motion to postpone the hearing should be filed...
Code of Federal Regulations, 2012 CFR
2012-04-01
... 22 Foreign Relations 2 2012-04-01 2009-04-01 true Motions. 1423.22 Section 1423.22 Foreign... PROCEEDINGS § 1423.22 Motions. (a) Filing of Motions. (1) Motions made prior to a hearing and any response... issuance of a complaint by the Regional Director any motion to postpone the hearing should be filed...