Tube Bulge Process : Theoretical Analysis and Finite Element Simulations
NASA Astrophysics Data System (ADS)
Velasco, Raphael; Boudeau, Nathalie
2007-05-01
This paper is focused on the determination of mechanics characteristics for tubular materials, using tube bulge process. A comparative study is made between two different models: theoretical model and finite element analysis. The theoretical model is completely developed, based first on a geometrical analysis of the tube profile during bulging, which is assumed to strain in arc of circles. Strain and stress analysis complete the theoretical model, which allows to evaluate tube thickness and state of stress, at any point of the free bulge region. Free bulging of a 304L stainless steel is simulated using Ls-Dyna 970. To validate FE simulations approach, a comparison between theoretical and finite elements models is led on several parameters such as: thickness variation at the free bulge region pole with bulge height, tube thickness variation with z axial coordinate, and von Mises stress variation with plastic strain. Finally, the influence of geometrical parameters deviations on flow stress curve is observed using analytical model: deviations of the tube outer diameter, its initial thickness and the bulge height measurement are taken into account to obtain a resulting error on plastic strain and von Mises stress.
A Content Analysis of Nine Literacy Journals, 2009-2014
ERIC Educational Resources Information Center
Parsons, Seth A.; Gallagher, Melissa A.
2016-01-01
The purpose of this study was to determine the topics being studied, theoretical perspectives being used, and methods being implemented in current literacy research. A research team completed a content analysis of nine journals from 2009 to 2014 to gather data. In the 1,238 articles analyzed, the topics, theoretical perspectives, research designs,…
A theoretical analysis of the current-voltage characteristics of solar cells
NASA Technical Reports Server (NTRS)
Fang, R. C. Y.; Hauser, J. R.
1977-01-01
The correlation of theoretical and experimental data is discussed along with the development of a complete solar cell analysis. The dark current-voltage characteristics, and the parameters for solar cells are analyzed. The series resistance, and impurity gradient effects on solar cells were studied, the effects of nonuniformities on solar cell performance were analyzed.
Pinning synchronization of delayed complex dynamical networks with nonlinear coupling
NASA Astrophysics Data System (ADS)
Cheng, Ranran; Peng, Mingshu; Yu, Weibin
2014-11-01
In this paper, we find that complex networks with the Watts-Strogatz or scale-free BA random topological architecture can be synchronized more easily by pin-controlling fewer nodes than regular systems. Theoretical analysis is included by means of Lyapunov functions and linear matrix inequalities (LMI) to make all nodes reach complete synchronization. Numerical examples are also provided to illustrate the importance of our theoretical analysis, which implies that there exists a gap between the theoretical prediction and numerical results about the minimum number of pinning controlled nodes.
Surface electrical properties experiment, Part 3
NASA Technical Reports Server (NTRS)
1974-01-01
A complete unified discussion of the electromagnetic response of a plane stratified structure is reported. A detailed and comprehensive analysis of the theoretical parts of the electromagnetic is given. The numerical problem of computing numbers of the electromagnetic field strengths is discussed. It is shown that the analysis of the conductive media is not very far removed from the theoretical analysis and the numerical difficulties are not as accute as for the low-loss problem. For Vol. 1, see N75-15570; for Vol. 2 see N75-15571.
Game theoretic analysis of physical protection system design
DOE Office of Scientific and Technical Information (OSTI.GOV)
Canion, B.; Schneider, E.; Bickel, E.
The physical protection system (PPS) of a fictional small modular reactor (SMR) facility have been modeled as a platform for a game theoretic approach to security decision analysis. To demonstrate the game theoretic approach, a rational adversary with complete knowledge of the facility has been modeled attempting a sabotage attack. The adversary adjusts his decisions in response to investments made by the defender to enhance the security measures. This can lead to a conservative physical protection system design. Since defender upgrades were limited by a budget, cost benefit analysis may be conducted upon security upgrades. One approach to cost benefitmore » analysis is the efficient frontier, which depicts the reduction in expected consequence per incremental increase in the security budget.« less
Complete synchronization of the global coupled dynamical network induced by Poisson noises.
Guo, Qing; Wan, Fangyi
2017-01-01
The different Poisson noise-induced complete synchronization of the global coupled dynamical network is investigated. Based on the stability theory of stochastic differential equations driven by Poisson process, we can prove that Poisson noises can induce synchronization and sufficient conditions are established to achieve complete synchronization with probability 1. Furthermore, numerical examples are provided to show the agreement between theoretical and numerical analysis.
Joint Services Electronics Program.
1985-12-31
year a comprehensive experimental study of the collision- enhanced Hanle-type resonances in Na vapor with various buffer gases has been completed...demonstrated theoretically that the collision-enhanced Hanle resonances are equivalent to the phenomenon of collision-induced transverse optical pumping. The...for the sensitivity of the mean sojourn times. We also developed a set of new equations based on perturbation analysis which calculates theoretically
Perceived barriers to completing an e-learning program on evidence-based medicine.
Gagnon, Marie-Pierre; Légaré, France; Labrecque, Michel; Frémont, Pierre; Cauchon, Michel; Desmartis, Marie
2007-01-01
The Continuing Professional Development Center of the Faculty of Medicine at Laval University offers an internet-based program on evidence-based medicine (EBM). After one year, only three physicians out of the 40 who willingly paid to register had completed the entire program. This descriptive study aimed to identify physicians' beliefs regarding their completion of this online program. Using theoretical concepts from the Theory of Planned Behaviour, a semi-structured telephone interview guide was developed to assess respondents' attitudes, perceived subjective norms, perceived obstacles and facilitating conditions with respect to completing this internet-based program. Three independent reviewers performed content analysis of the interview transcripts to obtain an appropriate level of reliability. Findings were shared and organised according to theoretical categories of beliefs. A total of 35 physicians (88% response rate) were interviewed. Despite perceived advantages to completing the internet-based program, barriers remained, especially those related to physicians' perceptions of time constraints. Lack of personal discipline and unfamiliarity with computers were also perceived as important barriers. This study offers a theoretical basis to understand physicians' beliefs towards completing an internet-based continuing medical education (CME) program on EBM. Based upon respondents' insights, several modifications were carried out to enhance the uptake of the program by physicians and, therefore, its implementation.
Theoretical prediction of airplane stability derivatives at subcritical speeds
NASA Technical Reports Server (NTRS)
Tulinius, J.; Clever, W.; Nieman, A.; Dunn, K.; Gaither, B.
1973-01-01
The theoretical development and application is described of an analysis for predicting the major static and rotary stability derivatives for a complete airplane. The analysis utilizes potential flow theory to compute the surface flow fields and pressures on any configuration that can be synthesized from arbitrary lifting bodies and nonplanar thick lifting panels. The pressures are integrated to obtain section and total configuration loads and moments due side slip, angle of attack, pitching motion, rolling motion, yawing motion, and control surface deflection. Subcritical compressibility is accounted for by means of the Gothert similarity rule.
Experimental and theoretical oscillator strengths of Mg I for accurate abundance analysis
NASA Astrophysics Data System (ADS)
Pehlivan Rhodin, A.; Hartman, H.; Nilsson, H.; Jönsson, P.
2017-02-01
Context. With the aid of stellar abundance analysis, it is possible to study the galactic formation and evolution. Magnesium is an important element to trace the α-element evolution in our Galaxy. For chemical abundance analysis, such as magnesium abundance, accurate and complete atomic data are essential. Inaccurate atomic data lead to uncertain abundances and prevent discrimination between different evolution models. Aims: We study the spectrum of neutral magnesium from laboratory measurements and theoretical calculations. Our aim is to improve the oscillator strengths (f-values) of Mg I lines and to create a complete set of accurate atomic data, particularly for the near-IR region. Methods: We derived oscillator strengths by combining the experimental branching fractions with radiative lifetimes reported in the literature and computed in this work. A hollow cathode discharge lamp was used to produce free atoms in the plasma and a Fourier transform spectrometer recorded the intensity-calibrated high-resolution spectra. In addition, we performed theoretical calculations using the multiconfiguration Hartree-Fock program ATSP2K. Results: This project provides a set of experimental and theoretical oscillator strengths. We derived 34 experimental oscillator strengths. Except from the Mg I optical triplet lines (3p 3P°0,1,2-4s 3S1), these oscillator strengths are measured for the first time. The theoretical oscillator strengths are in very good agreement with the experimental data and complement the missing transitions of the experimental data up to n = 7 from even and odd parity terms. We present an evaluated set of oscillator strengths, gf, with uncertainties as small as 5%. The new values of the Mg I optical triplet line (3p 3P°0,1,2-4s 3S1) oscillator strength values are 0.08 dex larger than the previous measurements.
NASA Astrophysics Data System (ADS)
Karabacak, M.; Kurt, M.; Cinar, M.; Ayyappan, S.; Sudha, S.; Sundaraganesan, N.
In this work, experimental and theoretical study on the molecular structure and the vibrational spectra of 3-aminobenzophenone (3-ABP) is presented. The vibrational frequencies of the title compound were obtained theoretically by DFT/B3LYP calculations employing the standard 6-311++G(d,p) basis set for optimized geometry and were compared with Fourier transform infrared spectrum (FTIR) in the region of 400-4000 cm-1 and with Fourier Transform Raman spectrum in the region of 50-4000 cm-1. Complete vibrational assignments, analysis and correlation of the fundamental modes for the title compound were carried out. The vibrational harmonic frequencies were scaled using scale factor, yielding a good agreement between the experimentally recorded and the theoretically calculated values.
Asres, Yihunie Hibstie; Mathuthu, Manny; Birhane, Marelgn Derso
2018-04-22
This study provides current evidence about cross-section production processes in the theoretical and experimental results of neutron induced reaction of uranium isotope on projectile energy range of 1-100 MeV in order to improve the reliability of nuclear stimulation. In such fission reactions of 235 U within nuclear reactors, much amount of energy would be released as a product that able to satisfy the needs of energy to the world wide without polluting processes as compared to other sources. The main objective of this work is to transform a related knowledge in the neutron-induced fission reactions on 235 U through describing, analyzing and interpreting the theoretical results of the cross sections obtained from computer code COMPLET by comparing with the experimental data obtained from EXFOR. The cross section value of 235 U(n,2n) 234 U, 235 U(n,3n) 233 U, 235 U(n,γ) 236 U, 235 U(n,f) are obtained using computer code COMPLET and the corresponding experimental values were browsed by EXFOR, IAEA. The theoretical results are compared with the experimental data taken from EXFOR Data Bank. Computer code COMPLET has been used for the analysis with the same set of input parameters and the graphs were plotted by the help of spreadsheet & Origin-8 software. The quantification of uncertainties stemming from both experimental data and computer code calculation plays a significant role in the final evaluated results. The calculated results for total cross sections were compared with the experimental data taken from EXFOR in the literature, and good agreement was found between the experimental and theoretical data. This comparison of the calculated data was analyzed and interpreted with tabulation and graphical descriptions, and the results were briefly discussed within the text of this research work. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.
A theoretical/experimental program to develop active optical pollution sensors
NASA Technical Reports Server (NTRS)
Mills, F. S.; Blais, R. N.; Kindle, E. C.
1977-01-01
Light detection and ranging (LIDAR) technology was applied to the assessment of air quality, and its usefulness was evaluated by actual field tests. Necessary hardware was successfully constructed and operated in the field. Measurements of necessary physical parameters, such as SO2 absorption coefficients were successfully completed and theoretical predictions of differential absorption performance were reported. Plume modeling improvements were proposed. A full scale field test of equipment, data analysis and auxiliary data support was conducted in Maryland during September 1976.
NASA Astrophysics Data System (ADS)
De Maré, G. R.; Panchenko, Yu. N.; Abramenkov, A. V.; Baird, M. S.; Tverezovsky, V. V.; Nizovtsev, A. V.; Bolesov, I. G.
2004-02-01
3,3-Dimethyl-1-(trimethylgermyl)cyclopropene ( I) was synthesised using a standard procedure. The IR and Raman spectra of I in the liquid phase were measured. The molecular geometry of I was optimised completely at the HF/6-31G* level. The HF/6-31G*//HF/6-31G* force field was calculated and scaled using the set of scale factors transferred from those determined previously for scaling the theoretical force fields of 3,3-dimethylbutene-1 and 1-methyl-, 1,2-dimethyl-, and 3,3-dimethylcyclopropene. The assignments of the observed vibrational bands were performed using the theoretical frequencies calculated from the scaled HF/6-31G*//HF/6-31G* force field and the ab initio values of the IR intensities, Raman cross-sections and depolarisation ratios. The theoretical spectra are given. The completely optimised structural parameters of I and its vibrational frequencies are compared with corresponding data of related molecules.
Noise model for low-frequency through-the-Earth communication
NASA Astrophysics Data System (ADS)
Raab, Frederick H.
2010-12-01
Analysis and simulation of through-the-Earth communication links and signal processing techniques require a more complete noise model than is needed for the analysis of conventional communication systems. This paper presents a multicomponent noise model that includes impulsive characteristics, direction-of-arrival characteristics, and effects of local geology. The noise model is derived from theoretical considerations and confirmed by field tests.
Development of a spinning wave heat engine
NASA Technical Reports Server (NTRS)
Zinn, B. T.; Powell, E. A.; Hubbartt, J. E.
1982-01-01
A theoretical analysis and an experimental investigation were conducted to assess the feasibility of developing a spinning wave heat engine. Such as engine would utilize a large amplitude traveling acoustic wave rotating around a cylindrica chamber, and it should not suffer from the inefficiency, noise, and intermittent thrust which characterizes pulse jet engines. The objective of this investigation was to determine whether an artificially driven large amplitude spinning transverse wave could induce a steady flow of air through the combustion chamber under cold flow conditions. In the theoretical analysis the Maslen and Moore perturbation technique was extended to study flat cylinders (pancake geometry) with completely open side walls and a central opening. In the parallel experimental study, a test moel was used to determine resonant frequencies and radial pressure distributions, as well as oscillatory and steady flow velocities at the inner and outer peripheries. The experimental frequency was nearly the same as the theoretical acoustic value for a model of the same outer diameter but without a central hole. Although the theoretical analysis did not predict a steady velocity component, simulaneous measurements of hotwire and microphone responses have shown that the spinning wave pumps a mean flow radially outward through the cavity.
NASA Astrophysics Data System (ADS)
Agrawal, L.; Bhardwaj, A.; Pal, S.; Kumar, A.
2007-11-01
This article presents the results of a detailed theoretical and experimental analysis carried out on a folded Z-shaped polarization coupled, electro-optically Q-switched laser resonator with Porro prisms and waveplates. The advantages of adding waveplates in a Porro prism resonator have been explored for creating high loss condition prior to Q-switching and obtaining variable reflectivity with fixed orientation of Porro prism. Generalized expressions have been derived in terms of azimuth angles and phase shifts introduced by the polarizing elements. These expressions corroborate with known reported results under appropriate substitutions. A specific case of a crossed Porro prism diode-pumped Nd:YAG laser has been theoretically and experimentally investigated. In the feedback arm, a 0.57λ waveplate oriented at 135° completely compensates the phase shift of a fused silica Porro prism and provides better tolerances than a BK-7 prism/0.60λ waveplate combination to stop prelasing. The fused silica prism/0.57λ combination with waveplate at 112° acts like a 100% mirror and was utilized for optimization of free running performance. The effective reflectivity was determined for various orientations of the quarter waveplate in the gain arm to numerically estimate the Q-switched laser pulse parameters through rate equation analysis. Experimental results match well with the theoretical analysis.
Charged particle and magnetic field research in space
NASA Technical Reports Server (NTRS)
1972-01-01
Research completed and in progress is described, related publications and reports are listed, and abstracts of papers and talks on results of the research are given. The charged particle research centered on OGO-5 and OGO-6 electron spectrometer data, and theoretical radiation belt studies. Work on the ATS-1 magnetometer project included development of production data reduction programs, development of spectral analysis procedures, and scientific studies of ULF waves at synchronous orbit. The magnetic fields research also included work on the Mariner project and theoretical studies on the solar wind.
ERIC Educational Resources Information Center
Hennessey, Maeghan N.; Terry, Robert; Martin, James E.; McConnell, Amber E.; Willis, Donna M.
2017-01-01
The researchers examined the theoretical factor structure fit and psychometric properties of the Transition Assessment and Goal Generator (TAGG). In the first study, 349 transition-aged students with disabilities, their special educators, and family members completed TAGG assessments, and using exploratory factor analysis (EFA)/confirmatory factor…
Multiphase Complete Exchange: A Theoretical Analysis
1993-08-01
Birkhiuser, Boston, 1984. 24 [9] C-T. Ho and M. T. Raghunath . Efficient communication primitives on hy- percubes. In Proc. 6th. DMCC, pages 390-397...1991. [10] C-T. Ho and M. T. Raghunath . Efficient communication primitives on hy- percubes. Technical Report RJ 7932 (72915), IBM, T. J. Watson Center
Effect of gravitational and aerodynamic torques on a rigid Skylab-type satellite
NASA Technical Reports Server (NTRS)
Sperling, H. J.
1974-01-01
A theoretical investigation of the influence of the aerodynamic torque on a Skylab-type satellite is presented. Only the case of free flow of uniform velocity and completely diffuse reflection is considered. It is found by linear stability analysis that the satellite has no stable equilibrium.
Factor Structure and Basic Psychometric Properties of the "Transition Assessment and Goal Generator"
ERIC Educational Resources Information Center
Hennessey, Maeghan N.; Terry, Robert; Martin, James E.; McConnell, Amber E.; Willis, Donna M.
2018-01-01
We examined the theoretical factor structure fit and psychometric properties of the "Transition Assessment and Goal Generator" (TAGG). In the first study, 349 transition-aged students with disabilities, their special educators, and family members completed TAGG assessments, and using exploratory factor analysis (EFA)/confirmatory factor…
NASA Astrophysics Data System (ADS)
Waeldele, F.
1983-01-01
The influence of sample shape deviations on the measurement uncertainties and the optimization of computer aided coordinate measurement were investigated for a circle and a cylinder. Using the complete error propagation law in matrix form the parameter uncertainties are calculated, taking the correlation between the measurement points into account. Theoretical investigations show that the measuring points have to be equidistantly distributed and that for a cylindrical body a measuring point distribution along a cross section is better than along a helical line. The theoretically obtained expressions to calculate the uncertainties prove to be a good estimation basis. The simple error theory is not satisfactory for estimation. The complete statistical data analysis theory helps to avoid aggravating measurement errors and to adjust the number of measuring points to the required measuring uncertainty.
Carey, Mariko; Jefford, Michael; Schofield, Penelope; Kelly, Siobhan; Krishnasamy, Meinir; Aranda, Sanchia
2006-04-01
Based on a theoretical framework, we developed an audiovisual resource to promote self-management of eight common chemotherapy side-effects. A patient needs analysis identified content domains, best evidence for preparing patients for threatening medical procedures and a systematic review of effective self-care strategies informed script content. Patients and health professionals were invited to complete a written evaluation of the video. A 25-min video was produced. Fifty health professionals and 37 patients completed the evaluation. All considered the video informative and easy to understand. The majority believed the video would reduce anxiety and help patients prepare for chemotherapy. Underpinned by a robust theoretical framework, we have developed an evidence-based resource that is perceived by both patients and health professionals as likely to enhance preparedness for chemotherapy.
NASA Technical Reports Server (NTRS)
Tseng, K.; Morino, L.
1975-01-01
A general formulation is presented for the analysis of steady and unsteady, subsonic and supersonic aerodynamics for complex aircraft configurations. The theoretical formulation, the numerical procedure, the description of the program SOUSSA (steady, oscillatory and unsteady, subsonic and supersonic aerodynamics) and numerical results are included. In particular, generalized forces for fully unsteady (complex frequency) aerodynamics for a wing-body configuration, AGARD wing-tail interference in both subsonic and supersonic flows as well as flutter analysis results are included. The theoretical formulation is based upon an integral equation, which includes completely arbitrary motion. Steady and oscillatory aerodynamic flows are considered. Here small-amplitude, fully transient response in the time domain is considered. This yields the aerodynamic transfer function (Laplace transform of the fully unsteady operator) for frequency domain analysis. This is particularly convenient for the linear systems analysis of the whole aircraft.
Joint research effort on vibrations of twisted plates, phase 1: Final results
NASA Technical Reports Server (NTRS)
Kielb, R. E.; Leissa, A. W.; Macbain, J. C.; Carney, K. S.
1985-01-01
The complete theoretical and experimental results of the first phase of a joint government/industry/university research study on the vibration characteristics of twisted cantilever plates are given. The study is conducted to generate an experimental data base and to compare many different theoretical methods with each other and with the experimental results. Plates with aspect ratios, thickness ratios, and twist angles representative of current gas turbine engine blading are investigated. The theoretical results are generated by numerous finite element, shell, and beam analysis methods. The experimental results are obtained by precision matching a set of twisted plates and testing them at two laboratories. The second and final phase of the study will concern the effects of rotation.
NOAA/DOE CWP structural analysis package. [CWPFLY, CWPEXT, COTEC, and XOTEC codes
DOE Office of Scientific and Technical Information (OSTI.GOV)
Pompa, J.A.; Lunz, D.F.
1979-09-01
The theoretical development and computer code user's manual for analysis of the Ocean Thermal Energy Conversion (OTEC) plant cold water pipe (CWP) are presented. The analysis of the CWP includes coupled platform/CWP loadngs and dynamic responses. This report with the exception of the Introduction and Appendix F was orginally published as Hydronautics, Inc., Technical Report No. 7825-2 (by Barr, Chang, and Thasanatorn) in November 1978. A detailed theoretical development of the equations describing the coupled platform/CWP system and preliminary validation efforts are described. The appendices encompass a complete user's manual, describing the inputs, outputs and operation of the four componentmore » programs, and detail changes and updates implemented since the original release of the code by Hydronautics. The code itself is available through NOAA's Office of Ocean Technology and Engineering Services.« less
Brian Buma; Jennifer K Costanza; Kurt Riitters
2017-01-01
The scale of investigation for disturbanceinfluenced processes plays a critical role in theoretical assumptions about stability, variance, and equilibrium, as well as conservation reserve and long-term monitoring program design. Critical consideration of scale is required for robust planning designs, especially when anticipating future disturbances whose exact...
Influence of incomplete fusion on complete fusion at energies above the Coulomb barrier
NASA Astrophysics Data System (ADS)
Shuaib, Mohd; Sharma, Vijay R.; Yadav, Abhishek; Sharma, Manoj Kumar; Singh, Pushpendra P.; Singh, Devendra P.; Kumar, R.; Singh, R. P.; Muralithar, S.; Singh, B. P.; Prasad, R.
2017-10-01
In the present work, excitation functions of several reaction residues in the system 19F+169Tm, populated via the complete and incomplete fusion processes, have been measured using off-line γ-ray spectroscopy. The analysis of excitation functions has been done within the framework of statistical model code pace4. The excitation functions of residues populated via xn and pxn channels are found to be in good agreement with those estimated by the theoretical model code, which confirms the production of these residues solely via complete fusion process. However, a significant enhancement has been observed in the cross-sections of residues involving α-emitting channels as compared to the theoretical predictions. The observed enhancement in the cross-sections has been attributed to the incomplete fusion processes. In order to have a better insight into the onset and strength of incomplete fusion, the incomplete fusion strength function has been deduced. At present, there is no theoretical model available which can satisfactorily explain the incomplete fusion reaction data at energies ≈4-6 MeV/nucleon. In the present work, the influence of incomplete fusion on complete fusion in the 19F+169Tm system has also been studied. The measured cross-section data may be important for the development of reactor technology as well. It has been found that the incomplete fusion strength function strongly depends on the α-Q value of the projectile, which is found to be in good agreement with the existing literature data. The analysis strongly supports the projectile-dependent mass-asymmetry systematics. In order to study the influence of Coulomb effect ({Z}{{P}}{Z}{{T}}) on incomplete fusion, the deduced strength function for the present work is compared with the nearby projectile-target combinations. The incomplete fusion strength function is found to increase linearly with {Z}{{P}}{Z}{{T}}, indicating a strong influence of Coulomb effect in the incomplete fusion reactions.
Experimental Verification of the Theory of Wind-Tunnel Boundary Interference
NASA Technical Reports Server (NTRS)
Theodorsen, Theodore; Silverstein, Abe
1935-01-01
The results of an experimental investigation on the boundary-correction factor are presented in this report. The values of the boundary-correction factor from the theory, which at the present time is virtually completed, are given in the report for all conventional types of tunnels. With the isolation of certain disturbing effects, the experimental boundary-correction factor was found to be in satisfactory agreement with the theoretically predicted values, thus verifying the soundness and sufficiency of the theoretical analysis. The establishment of a considerable velocity distortion, in the nature of a unique blocking effect, constitutes a principal result of the investigation.
A PARAMETRIC STUDY OF BCS RF SURFACE IMPEDANCE WITH MAGNETIC FIELD USING THE XIAO CODE
DOE Office of Scientific and Technical Information (OSTI.GOV)
Reece, Charles E.; Xiao, Binping
2013-09-01
A recent new analysis of field-dependent BCS rf surface impedance based on moving Cooper pairs has been presented.[1] Using this analysis coded in Mathematica TM, survey calculations have been completed which examine the sensitivities of this surface impedance to variation of the BCS material parameters and temperature. The results present a refined description of the "best theoretical" performance available to potential applications with corresponding materials.
NASA Astrophysics Data System (ADS)
Livshts, Mikhail A.; Khomyakova, Elena; Evtushenko, Evgeniy G.; Lazarev, Vassili N.; Kulemin, Nikolay A.; Semina, Svetlana E.; Generozov, Edward V.; Govorun, Vadim M.
2015-11-01
Exosomes, small (40-100 nm) extracellular membranous vesicles, attract enormous research interest because they are carriers of disease markers and a prospective delivery system for therapeutic agents. Differential centrifugation, the prevalent method of exosome isolation, frequently produces dissimilar and improper results because of the faulty practice of using a common centrifugation protocol with different rotors. Moreover, as recommended by suppliers, adjusting the centrifugation duration according to rotor K-factors does not work for “fixed-angle” rotors. For both types of rotors - “swinging bucket” and “fixed-angle” - we express the theoretically expected proportion of pelleted vesicles of a given size and the “cut-off” size of completely sedimented vesicles as dependent on the centrifugation force and duration and the sedimentation path-lengths. The proper centrifugation conditions can be selected using relatively simple theoretical estimates of the “cut-off” sizes of vesicles. Experimental verification on exosomes isolated from HT29 cell culture supernatant confirmed the main theoretical statements. Measured by the nanoparticle tracking analysis (NTA) technique, the concentration and size distribution of the vesicles after centrifugation agree with those theoretically expected. To simplify this “cut-off”-size-based adjustment of centrifugation protocol for any rotor, we developed a web-calculator.
Practical research on the teaching of Optical Design
NASA Astrophysics Data System (ADS)
Fan, Changjiang; Ren, Zhijun; Ying, Chaofu; Peng, Baojin
2017-08-01
Optical design, together with applied optics, forms a complete system from basic theory to application theory, and it plays a very important role in professional education. In order to improve senior undergraduates' understanding of optical design, this course is divided into three parts: theoretical knowledge, software design and product processing. Through learning theoretical knowledge, students can master the aberration theory and the design principles of typical optical system. By using ZEMAX(an imaging design software), TRACEPRO(a lighting optical design software), SOLIDWORKS or PROE( mechanical design software), student can establish a complete model of optical system. Student can use carving machine located in lab or cooperative units to process the model. Through the above three parts, student can learn necessary practical knowledge and get improved in their learning and analysis abilities, thus they can also get enough practice to prompt their creative abilities, then they could gradually change from scientific theory learners to an Optics Engineers.
NASA Astrophysics Data System (ADS)
Arokiasamy, A.; Manikandan, G.; Thanikachalam, V.; Gokula Krishnan, K.
2017-04-01
Synthesis and computational optimization studies have been carried out by Hartree-Fock (HF) and Density Functional Theory (DFT-B3LYP) methods with 6-31+G(d, p) basis set for 2-((E)-(2-(2-cyanoacetyl)hydrazono)methyl)-4-((E)-phenyldiazenyl)phenyl methyl carbonate (CHPMC). The stable configuration of CHPMC was confirmed theoretically by potential energy surface scan analysis. The complete vibrational assignments were performed on the basis of total energy distribution (TED) analysis. The vibrational properties studied by IR and Raman spectroscopic data complemented by quantum chemical calculations support the formation of intramolecular hydrogen bond. Furthermore, the UV-Vis spectra are interpreted in terms of TD-DFT quantum chemical calculations. The shapes of the simulated absorption spectra are in good agreement with the experimental data. The comparison between the experimental and theoretical values of FT-IR, FT-Raman vibrational spectra, NMR (1H and 13C) and UV-Vis spectra have also been discussed.
NASA Astrophysics Data System (ADS)
Sakli, Hedi; Benzina, Hafedh; Aguili, Taoufik; Tao, Jun Wu
2009-08-01
This paper is an analysis of rectangular waveguide completely full of ferrite magnetized longitudinally. The analysis is based on the formulation of the transverse operator method (TOM), followed by the application of the Galerkin method. We obtain an eigenvalue equation system. The propagation constant of some homogenous and anisotropic waveguide structures with ferrite has been obtained. The results presented here show that the transverse operator formulation is not only an elegant theoretical form, but also a powerful and efficient analysis method, it is useful to solve a number of the propagation problems in electromagnetic. One advantage of this method is that it presents a fast convergence. Numerical examples are given for different cases and compared with the published results. A good agreement is obtained.
Millimeter wave generation by relativistic electron beams and microwave-plasma interaction
NASA Astrophysics Data System (ADS)
Kuo, Spencer
1990-12-01
The design and operation of a compact, high power, millimeter wave source (cusptron) has been completed and proven successful. Extensive theoretical analysis of cusptron beam and rf dynamics has been carried out and published. Theory agrees beautifully with experiment. Microwave Bragg scattering due to been achieved by using expanding plasmas to upshift rf signal frequencies.
Point source detection in infrared astronomical surveys
NASA Technical Reports Server (NTRS)
Pelzmann, R. F., Jr.
1977-01-01
Data processing techniques useful for infrared astronomy data analysis systems are reported. This investigation is restricted to consideration of data from space-based telescope systems operating as survey instruments. In this report the theoretical background for specific point-source detection schemes is completed, and the development of specific algorithms and software for the broad range of requirements is begun.
Quantum entanglement helps in improving economic efficiency
NASA Astrophysics Data System (ADS)
Du, Jiangfeng; Ju, Chenyong; Li, Hui
2005-02-01
We propose an economic regulation approach based on quantum game theory for the government to reduce the abuses of oligopolistic competition. Theoretical analysis shows that this approach can help government improve the economic efficiency of the oligopolistic market, and help prevent monopoly due to incorrect information. These advantages are completely attributed to the quantum entanglement, a unique quantum mechanical character.
ERIC Educational Resources Information Center
Kearney, W. Sean; Webb, Michael; Goldhorn, Jeff; Peters, Michelle L.
2013-01-01
This article presents a quantitative study utilizing HLM to analyze classroom walkthrough data completed by principals within 87 secondary mathematics classrooms across 9 public schools in Texas. This research is based on the theoretical framework of learner engagement as established by Argryis & Schon (1996), and refined by Marks (2000). It…
Position and Disposition: The Contextual Development of Human Values
ERIC Educational Resources Information Center
Longest, Kyle C.; Hitlin, Steven; Vaisey, Stephen
2013-01-01
Research on the importance of values often focuses primarily on one domain of social predictors (e.g., economic) or limits its scope to a single dimension of values. We conduct a simultaneous analysis of a wide range of theoretically important social influences and a more complete range of individuals' value orientations, focusing both on value…
A Curriculum Development Route Map for a Technology Enhanced Learning Era
ERIC Educational Resources Information Center
Castañeda, Linda; Prendes, Paz
2013-01-01
In this paper we are trying to present a model of analysis that includes a comprehensive perspective of the state of the art in the specialized literature about curriculum development. From this theoretical approach, we get a complete curriculum overview. Including insights into: what are the curriculum principal elements, what we already know…
Hennessy, Michael; Bleakley, Amy; Ellithorpe, Morgan
2018-03-01
The reasoned action approach is one of the most successful behavioral theories in the history of social psychology. This study outlines the theoretical principles of reasoned action and considers when it is appropriate to augment it with a new variable. To demonstrate, we use survey data collected from a 4 to 17 year old U.S. adolescents to test how the 'prototype' variables fit into reasoned action approach. Through confirmatory factor analysis, we find that the prototype measures are normative pressure measures and when treated as a separate theoretical construct, prototype identity is not completely mediated by the proximal predictors of behavioral intention. We discuss the assumptions of the two theories and finally consider the distinction between augmenting a specific theory versus combining measures derived from different theoretical perspectives.
NASA Astrophysics Data System (ADS)
Li, Xiao-Hong; Liu, Xiang-Ru; Zhang, Xian-Zhou
2011-01-01
The vibrational frequencies of three substituted 4-thioflavones in the ground state have been calculated using the Hartree-Fock and density functional method (B3LYP) with 6-31G* and 6-31+G** basis sets. The structural analysis shows that there exists H-bonding in the selected compounds and the hydrogen bond lengths increase with the augment of the conjugate parameters of the substituent group on the benzene ring. A complete vibrational assignment aided by the theoretical harmonic wavenumber analysis was proposed. The theoretical spectrograms for FT-IR spectra of the title compounds have been constructed. In addition, it is noted that the selected compounds show significant activity against Shigella flexniri. Several electronic properties and thermodynamic parameters were also calculated.
Theoretical and experimental studies of reentry plasmas
NASA Technical Reports Server (NTRS)
Dunn, M. G.; Kang, S.
1973-01-01
A viscous shock-layer analysis was developed and used to calculate nonequilibrium-flow species distributions in the plasma layer of the RAM vehicle. The theoretical electron-density results obtained are in good agreement with those measured in flight. A circular-aperture flush-mounted antenna was used to obtain a comparison between theoretical and experimental antenna admittance in the presence of ionized boundary layers of low collision frequency. The electron-temperature and electron-density distributions in the boundary layer were independently measured. The antenna admittance was measured using a four-probe microwave reflectometer and these measured values were found to be in good agreement with those predicted. Measurements were also performed with another type of circular-aperture antenna and good agreement was obtained between the calculations and the experimental results. A theoretical analysis has been completed which permits calculation of the nonequilibrium, viscous shock-layer flow field for a sphere-cone body. Results are presented for two different bodies at several different altitudes illustrating the influences of bluntness and chemical nonequilibrium on several gas dynamic parameters of interest. Plane-wave transmission coefficients were calculated for an approximate space-shuttle body using a typical trajectory.
A research program in magnetogasdynamics utilizing hypervelocity coaxial plasma generators
NASA Technical Reports Server (NTRS)
Spight, C.
1976-01-01
A broadly-gauged research program in magnetogasdynamics utilizing hypervelocity coaxial plasma generators is presented. A complete hypervelocity coaxial plasma generator facility was assembled and tested. Significant progress was made in the direction of understanding the important processes in the interaction of hypervelocity MGD flow with transverse applied fields. It is now proposed to utilize the accumulated experimental capability and theoretical analysis in application to the analysis and design parameterization of pulsed magnetogasdynamic direct energy convertor configurations.
NASA Astrophysics Data System (ADS)
Seyedkatouli, Seyedabdollah; Vakili, Mohammad; Tayyari, Sayyed Faramarz; Afzali, Raheleh
2018-05-01
This paper presents a combined experimental and theoretical study on the Cusbnd O bond strength of copper (II) α-methylacetylacetonate, Cu(3-Meacac)2, and copper (II) α-ethylacetylacetonate, Cu(3-Etacac)2, complexes in comparison to that in copper (II) acetylacetonate, Cu(acac)2. For this purpose, the molecular structure, UV spectra, and complete vibrational assignment of target molecules were investigated by DFT, Natural Bond Orbital (NBO) theory, and Atoms-in-Molecules (AIM) analysis at the B3LYP/6-311G* level of theory. The mentioned results are compared with those in Cu(acac)2. Fourier transform-Raman, IR, and UV spectra of these complexes have been also recorded. A complete assignment of the observed band frequencies has been done. All theoretical and experimental spectroscopic results are consisting with a stronger metal-oxygen bond in Cu(3-Meacac)2 and Cu(3-Etacac)2 complexes compared with Cu(acac)2. In addition, these results confirm that there is no significant difference between the Cusbnd O bond strength of the Cu(3-Meacac)2 and Cu(3-Etacac)2 complexes.
An inlet analysis for the NASA hypersonic research engine aerothermodynamic integration model
NASA Technical Reports Server (NTRS)
Andrews, E. H., Jr.; Russell, J. W.; Mackley, E. A.; Simmonds, A. L.
1974-01-01
A theoretical analysis for the inlet of the NASA Hypersonic Research Engine (HRE) Aerothermodynamic Integration Model (AIM) has been undertaken by use of a method-of-characteristics computer program. The purpose of the analysis was to obtain pretest information on the full-scale HRE inlet in support of the experimental AIM program (completed May 1974). Mass-flow-ratio and additive-drag-coefficient schedules were obtained that well defined the range effected in the AIM tests. Mass-weighted average inlet total-pressure recovery, kinetic energy efficiency, and throat Mach numbers were obtained.
Salim, Agus; Mackinnon, Andrew; Christensen, Helen; Griffiths, Kathleen
2008-09-30
The pre-test-post-test design (PPD) is predominant in trials of psychotherapeutic treatments. Missing data due to withdrawals present an even bigger challenge in assessing treatment effectiveness under the PPD than under designs with more observations since dropout implies an absence of information about response to treatment. When confronted with missing data, often it is reasonable to assume that the mechanism underlying missingness is related to observed but not to unobserved outcomes (missing at random, MAR). Previous simulation and theoretical studies have shown that, under MAR, modern techniques such as maximum-likelihood (ML) based methods and multiple imputation (MI) can be used to produce unbiased estimates of treatment effects. In practice, however, ad hoc methods such as last observation carried forward (LOCF) imputation and complete-case (CC) analysis continue to be used. In order to better understand the behaviour of these methods in the PPD, we compare the performance of traditional approaches (LOCF, CC) and theoretically sound techniques (MI, ML), under various MAR mechanisms. We show that the LOCF method is seriously biased and conclude that its use should be abandoned. Complete-case analysis produces unbiased estimates only when the dropout mechanism does not depend on pre-test values even when dropout is related to fixed covariates including treatment group (covariate-dependent: CD). However, CC analysis is generally biased under MAR. The magnitude of the bias is largest when the correlation of post- and pre-test is relatively low.
A vibrational study of inulin by means of experimental and theoretical methods
NASA Astrophysics Data System (ADS)
Balan, C.; Chis, M. I.; Rachisan, A. L.; Baia, M.
2018-07-01
Inulin, a natural polymer formed by several units of fructose and just one unit of glucose, is found in different plants or directly in some fruits or vegetables. Due to its structure it has been used in many applications from medicine, pharmacology or food industry. In spite of this, a complete vibrational analysis of the molecule is missing in the literature. Moreover, there are contradictory results regarding the assignment of certain vibrational modes. Therefore, the aim of this study was to obtain a comprehensive vibrational investigation of inulin by means of experimental (FT-IR and Raman spectroscopy) and theoretical (density functional theory -DFT simulations) methods.
Study of inelastic e-Cd and e-Zn collisions
NASA Astrophysics Data System (ADS)
Piwinski, Mariusz; Klosowski, Lukasz; Dziczek, Darek; Chwirot, Stanislaw
2016-09-01
Electron-photon coincidence experiments are well known for providing more detailed information about electron-atom collision than any other technique. The Electron Impact Coherence Parameters (EICP) values obtained in such studies deliver the most complete characterization of the inelastic collision and allow for a verification of proposed theoretical models. We present the results of Stokes and EICP parameters characterising electronic excitation of the lowest singlet P-state of cadmium and zinc atoms for various collision energies. The experiments were performed using electron-photon coincidence technique in the coherence analysis version. The obtained data are presented and compared with existing CCC and RDWA theoretical predictions.
Govindasamy, P; Gunasekaran, S
2015-01-01
In this work, the vibrational spectral analysis was carried out by using FT-Raman and FT-IR spectroscopy in the range 4000-50 cm(-1) and 4000-450 cm(-1) respectively for 4-(6-methoxynaphthalen-2-yl) butan-2-one (abbreviated as 4MNBO) molecule. Theoretical calculations were performed by density functional theory (DFT/B3LYP) method using 6-311G(d,p) and 6-311++G(d,p) basis sets. The difference between the observed and calculated wavenumber value of most of the fundamentals were very small. The complete vibrational assignments of wavenumbers were made on the basis of potential energy distribution (PED). The UV-Vis spectrum was recorded in the methanol solution. The energy, wavelength and oscillator's strength were calculated by Time Dependent Density Functional Theory (TD-DFT) and matched to the experimental findings. The intramolecular contacts have been interpreted using natural bond orbital (NBO) and natural localized molecular orbital (NLMO) analysis. Thermodynamic properties of 4MNBO at different temperature have been calculated. The molecular electrostatic potential surface (MESP) and Frontier molecular orbital's (FMO's) analysis were investigated using theoretical calculations. Copyright © 2015 Elsevier B.V. All rights reserved.
Improved separability criteria via some classes of measurements
NASA Astrophysics Data System (ADS)
Shen, Shu-Qian; Li, Ming; Li-Jost, Xianqing; Fei, Shao-Ming
2018-05-01
The entanglement detection via local measurements can be experimentally implemented. Based on mutually unbiased measurements and general symmetric informationally complete positive-operator-valued measures, we present separability criteria for bipartite quantum states, which, by theoretical analysis, are stronger than the related existing criteria via these measurements. Two detailed examples are supplemented to show the efficiency of the presented separability criteria.
ERIC Educational Resources Information Center
Gardner, Susan K.
2010-01-01
Socialization has become the common theoretical framework used to better understand the complexity of the doctoral student experience. In particular, theories of socialization have been connected to the issue of attrition in doctoral education, with researchers often attributing poor or inappropriate socialization to a student's decision to depart…
NASA Technical Reports Server (NTRS)
Myrabo, Leik N.; Blandino, John S.; Borkowski, Chris A.; Cross, David P.; Frazier, Scott R.; Hill, Stephen C.; Mitty, Todd J.; Moder, Jeffrey P.; Morales, Ciro; Nyberg, Gregory A.
1987-01-01
The detailed design of a beam-powered transatmospheric vehicle, the Apollo Lightcraft, was selected as the project for the design course. The principal goal is to reduce the LEO payload delivery cost by at least three orders of magnitude below the Space Shuttle Orbiter in the post 2020 era. The completely reusable, single-stage-to-orbit shuttlecraft will take off and land vertically, and have a reentry heat shield integrated with its lower surface. At appropriate points along the launch trajectory, the combined cycle propulsion system will transition through three or four airbreathing modes, and finally use a pure rocket mode for orbital insertion. The objective for the Spring semester propulsion source was to design and perform a detailed theoretical analysis on an advanced combined-cycle engine suitable for the Apollo Lightcraft. The preliminary theoretical analysis of this combined-cycle engine is now completed, and the acceleration performance along representative orbital trajectories was simulated. The total round trip cost is $3430 or $686 per person. This represents a payload delivery cost of $3.11/lb, which is a factor of 1000 below the STS. The Apollo Lightcraft concept is now ready for a more detailed investigation during the Fall semester Transatmosphere Vehicle Design course.
Analysis of an x-ray mirror made from piezoelectric bimorph
NASA Astrophysics Data System (ADS)
Zhang, Yao; Li, Ming; Tang, Shanzhi; Gao, Junxiang; Zhang, Weiwei; Zhu, Peiping
2017-07-01
Theoretical analysis of the mechanical behavior of an x-ray mirror made from piezoelectric bimorph is presented. A complete two-dimensional relationship between the radius of curvature of the mirror and the applied voltage is derived. The accuracy of this relationship is studied by comparing the figures calculated by the relationship and Finite Element Analysis. The influences of several critical parameters in the relationship on the radius of curvature are analyzed. It is found that piezoelectric coefficient d31 is the main material property parameter that dominates the radius of curvature, and that the optimal thickness of PZT plate corresponding to largest bending range is 2.5 times of that of faceplate. It is demonstrated that the relationship is helpful for us to complete the primary design of the x-ray mirror made from piezoelectric bimorph.
Prototypes Reflect Normative Perceptions: Implications for the Development of Reasoned Action Theory
Hennessy, Michael; Bleakley, Amy; Ellithorpe, Morgan
2017-01-01
The reasoned action approach is one of the most successful behavioral theories in the history of social psychology. This study outlines the theoretical principles of reasoned action and considers when it is appropriate to augment it with a new variable. To demonstrate, we use survey data collected from a 4–17 year old U.S. adolescents to test how the “prototype” variables fit into reasoned action approach. Through confirmatory factor analysis, we find that the prototype measures are normative pressure measures and when treated as a separate theoretical construct, prototype identity is not completely mediated by the proximal predictors of behavioral intention. We discuss the assumptions of the two theories and finally consider the distinction between augmenting a specific theory versus combining measures derived from different theoretical perspectives. PMID:28612624
NASA Technical Reports Server (NTRS)
Mcknight, R. L.
1985-01-01
A series of interdisciplinary modeling and analysis techniques that were specialized to address three specific hot section components are presented. These techniques will incorporate data as well as theoretical methods from many diverse areas including cycle and performance analysis, heat transfer analysis, linear and nonlinear stress analysis, and mission analysis. Building on the proven techniques already available in these fields, the new methods developed will be integrated into computer codes to provide an accurate, and unified approach to analyzing combustor burner liners, hollow air cooled turbine blades, and air cooled turbine vanes. For these components, the methods developed will predict temperature, deformation, stress and strain histories throughout a complete flight mission.
Liquid-vapor rectilinear diameter revisited
NASA Astrophysics Data System (ADS)
Garrabos, Y.; Lecoutre, C.; Marre, S.; Beysens, D.; Hahn, I.
2018-02-01
In the modern theory of critical phenomena, the liquid-vapor density diameter in simple fluids is generally expected to deviate from a rectilinear law approaching the critical point. However, by performing precise scannerlike optical measurements of the position of the SF6 liquid-vapor meniscus, in an approach much closer to criticality in temperature and density than earlier measurements, no deviation from a rectilinear diameter can be detected. The observed meniscus position from far (10 K ) to extremely close (1 mK ) to the critical temperature is analyzed using recent theoretical models to predict the complete scaling consequences of a fluid asymmetry. The temperature dependence of the meniscus position appears consistent with the law of rectilinear diameter. The apparent absence of the critical hook in SF6 therefore seemingly rules out the need for the pressure scaling field contribution in the complete scaling theoretical framework in this SF6 analysis. More generally, this work suggests a way to clarify the experimental ambiguities in the simple fluids for the near-critical singularities in the density diameter.
Report on the Domestic Natural Disaster Health Workforce
2011-11-30
DEMPS volunteers are required to review and ensure that their information in the DEMPs database is current and complete on a quarterly basis. Retiring...emergency and critical-care nurses; and (3) paramedics. • Uses a pilot case study focusing on a theoretical major earthquake scenario in the ... on the three core occupational sub- groups. • Incorporates feedback from a multi-stakeholder conference. This landscape analysis supports
The Background to Current Theories of Scuffing
1973-01-01
attention because, by neglecting axial flow , it can be treated in two dimensions. This has resulted in a fairly complete theoretical analysis...the contact. This method was essentially one of measuring the volume rate of flow through the contact, which was directly related to the pad...exit constriction. The pressure and temperature were also measured in the axial direction (105) and the results indicated that side leakage was
Fundamental studies in geodynamics
NASA Technical Reports Server (NTRS)
Anderson, D. L.; Hager, B. H.; Kanamori, H.
1981-01-01
Research in fundamental studies in geodynamics continued in a number of fields including seismic observations and analysis, synthesis of geochemical data, theoretical investigation of geoid anomalies, extensive numerical experiments in a number of geodynamical contexts, and a new field seismic volcanology. Summaries of work in progress or completed during this report period are given. Abstracts of publications submitted from work in progress during this report period are attached as an appendix.
Stress analysis and damage evaluation of flawed composite laminates by hybrid-numerical methods
NASA Technical Reports Server (NTRS)
Yang, Yii-Ching
1992-01-01
Structural components in flight vehicles is often inherited flaws, such as microcracks, voids, holes, and delamination. These defects will degrade structures the same as that due to damages in service, such as impact, corrosion, and erosion. It is very important to know how a structural component can be useful and survive after these flaws and damages. To understand the behavior and limitation of these structural components researchers usually do experimental tests or theoretical analyses on structures with simulated flaws. However, neither approach has been completely successful. As Durelli states that 'Seldom does one method give a complete solution, with the most efficiency'. Examples of this principle is seen in photomechanics which additional strain-gage testing can only average stresses at locations of high concentration. On the other hand, theoretical analyses including numerical analyses are implemented with simplified assumptions which may not reflect actual boundary conditions. Hybrid-Numerical methods which combine photomechanics and numerical analysis have been used to correct this inefficiency since 1950's. But its application is limited until 1970's when modern computer codes became available. In recent years, researchers have enhanced the data obtained from photoelasticity, laser speckle, holography and moire' interferometry for input of finite element analysis on metals. Nevertheless, there is only few of literature being done on composite laminates. Therefore, this research is dedicated to this highly anisotropic material.
Study of ICRF wave propagation and plasma coupling efficiency in a linear magnetic mirror device
DOE Office of Scientific and Technical Information (OSTI.GOV)
Peng, S.Y.
1991-07-01
Ion Cyclotron Range of Frequency (ICRF) wave propagation in an inhomogeneous axial magnetic field in a cylindrical plasma-vacuum system has historically been inadequately modelled. Previous works either sacrifice the cylindrical geometry in favor of a simpler slab geometry, concentrate on the resonance region, use a single mode to represent the entire field structure, or examine only radial propagation. This thesis performs both analytical and computational studies to model the ICRF wave-plasma coupling and propagation problem. Experimental analysis is also conducted to compare experimental results with theoretical predictions. Both theoretical as well as experimental analysis are undertaken as part of themore » thesis. The theoretical studies simulate the propagation of ICRF waves in an axially inhomogeneous magnetic field and in cylindrical geometry. Two theoretical analysis are undertaken - an analytical study and a computational study. The analytical study treats the inhomogeneous magnetic field by transforming the (r,z) coordinate into another coordinate system ({rho},{xi}) that allows the solution of the fields with much simpler boundaries. The plasma fields are then Fourier transformed into two coupled convolution-integral equations which are then differenced and solved for both the perpendicular mode number {alpha} as well as the complete EM fields. The computational study involves a multiple eigenmode computational analysis of the fields that exist within the plasma-vacuum system. The inhomogeneous axial field is treated by dividing the geometry into a series of transverse axial slices and using a constant dielectric tensor in each individual slice. The slices are then connected by longitudinal boundary conditions.« less
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.
NASA Technical Reports Server (NTRS)
Mcrae, Glenn A.; Cohen, Edward A.; Sponsler, Michael B.; Dougherty, Dennis A.
1986-01-01
The microwave spectra of five isotopic species of bicyclo (1.1.1) pentanone have been investigated. The rotational constants along with various centrifugal distortion constants for each species have been determined. From the rotational constants, a complete r(s) structure has been determined for the heavy atoms. Analysis of Stark effect measurements has shown the dipole moment to be along the a principal inertial axis with a magnitude of 3.164 (5) D. These results are compared with those obtained by four current theoretical methods: molecular mechanics (MM2), MNDO, and Hartree-Fock ab initio theory with STO-3G and 3-21G basis sets.
Bernot, Kevin; Luzon, Javier; Bogani, Lapo; Etienne, Mael; Sangregorio, Claudio; Shanmugam, Muralidharan; Caneschi, Andrea; Sessoli, Roberta; Gatteschi, Dante
2009-04-22
A mixed theoretical and experimental approach was used to determine the local magnetic anisotropy of the dysprosium(III) ion in a low-symmetry environment. The susceptibility tensor of the monomeric species having the formula [Dy(hfac)(3)(NIT-C(6)H(4)-OEt)(2)], which contains nitronyl nitroxide (NIT-R) radicals, was determined at various temperatures through angle-resolved magnetometry. These results are in agreement with ab initio calculations performed using the complete active space self-consistent field (CASSCF) method, validating the predictive power of this theoretical approach for complex systems containing rare-earth ions, even in low-symmetry environments. Susceptibility measurements performed with the applied field along the easy axis eventually permitted a detailed analysis of the temperature and field dependence of the magnetization, providing evidence that the Dy ion transmits an antiferromagnetic interaction between radicals but that the Dy-radical interaction is ferromagnetic.
Analysis of Vibrational Harmonic Response for Printing Double-Sheet Detecting System via ANSYS
NASA Astrophysics Data System (ADS)
Guo, Qiang; Cai, Ji-Fei; Wang, Yan; Zhang, Yang
In order to explore the influence of the harmonic response of system vibration upon the stability of the double-sheet detector system, the mathematical model of vibrational system is established via the mechanical dynamic theory. Vibrational system of double-sheet detector is studied by theoretical modeling, and the dynamic simulation to obtain the amplitude/phase frequency response curve of the system based on ANSYS is completed to make a comparison with the theoretical results. It is shown that the theoretical value is basically consistent with that calculated through ANSYS. Conclusion vibrational characteristics of double-sheet detection system is obtained quickly and accurately, and propound solving measures by some crucial factors, such as the harmonic load, mass and stiffness, which will affect the vibration of the system, contribute to the finite element method is applied to the complex multiple-degree-of-freedom system.
Analysis and testing of a new method for drop size measurement using laser scatter interferometry
NASA Technical Reports Server (NTRS)
Bachalo, W. D.; Houser, M. J.
1984-01-01
Research was conducted on a laser light scatter detection method for measuring the size and velocity of spherical particles. The method is based upon the measurement of the interference fringe pattern produced by spheres passing through the intersection of two laser beams. A theoretical analysis of the method was carried out using the geometrical optics theory. Experimental verification of the theory was obtained by using monodisperse droplet streams. Several optical configurations were tested to identify all of the parametric effects upon the size measurements. Both off-axis forward and backscatter light detection were utilized. Simulated spray environments and fuel spray nozzles were used in the evaluation of the method. The measurements of the monodisperse drops showed complete agreement with the theoretical predictions. The method was demonstrated to be independent of the beam intensity and extinction resulting from the surrounding drops. Signal processing concepts were considered and a method was selected for development.
NASA Astrophysics Data System (ADS)
Borah, Mukunda Madhab; Gomti Devi, Th.
2018-07-01
In the present work Tamoxifen, Estradiol and their interaction are studied using the experimental and theoretical methodologies. The spectral characterization was made by using Raman, FTIR, DFT and VEDA calculation. The optimization of the molecules have been studied using basis set B3LYP/6-31 G(d,p). Complete vibrational assignment of Tamoxifen, Estradiol and Estradiol + Tamoxifen have been attempted and the potential energy distribution and normal mode analysis had also been carried out to determine the contributions of bond oscillators in each normal mode. We have optimized several binding modes of Estradiol and Tamoxifen and taken the lowest energy conformer in our interest. The molecular geometry, HOMO-LUMO energy gap, molecular hardness (η), ionization energy (IE), electron affinity (EA), total energy and dipole moment were analyzed. The observed experimental and the scaled theoretical results were found in good agreement.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dass, Amala; Jones, Tanya; Rambukwella, Milan
We report the complete X-ray crystallographic structure as determined through single crystal X-ray diffraction and a thorough theoretical analysis of the green gold Au30(S-tBu)18. While the structure of Au30S(S-tBu)18 with 19 sulfur atoms has been reported, the crystal structure of Au30(S-tBu)18 without the μ3-sulfur has remained elusive until now, though matrix-assisted laser desorption ionization mass spectrometry (MALDI-MS) and electrospray ionization mass spectrometry (ESI-MS) data unequivocally shows its presence in abundance. The Au30(S-tBu)18 nanomolecule is not only distinct in its crystal structure but has unique temperature dependent optical properties. Structure determination allows a rigorous comparison and an excellent agreement with theoreticalmore » predictions of structure, stability, and optical response.« less
Informational analysis for compressive sampling in radar imaging.
Zhang, Jingxiong; Yang, Ke
2015-03-24
Compressive sampling or compressed sensing (CS) works on the assumption of the sparsity or compressibility of the underlying signal, relies on the trans-informational capability of the measurement matrix employed and the resultant measurements, operates with optimization-based algorithms for signal reconstruction and is thus able to complete data compression, while acquiring data, leading to sub-Nyquist sampling strategies that promote efficiency in data acquisition, while ensuring certain accuracy criteria. Information theory provides a framework complementary to classic CS theory for analyzing information mechanisms and for determining the necessary number of measurements in a CS environment, such as CS-radar, a radar sensor conceptualized or designed with CS principles and techniques. Despite increasing awareness of information-theoretic perspectives on CS-radar, reported research has been rare. This paper seeks to bridge the gap in the interdisciplinary area of CS, radar and information theory by analyzing information flows in CS-radar from sparse scenes to measurements and determining sub-Nyquist sampling rates necessary for scene reconstruction within certain distortion thresholds, given differing scene sparsity and average per-sample signal-to-noise ratios (SNRs). Simulated studies were performed to complement and validate the information-theoretic analysis. The combined strategy proposed in this paper is valuable for information-theoretic orientated CS-radar system analysis and performance evaluation.
The workload book: Assessment of operator workload to engineering systems
NASA Technical Reports Server (NTRS)
Gopher, D.
1983-01-01
The structure and initial work performed toward the creation of a handbook for workload analysis directed at the operational community of engineers and human factors psychologists are described. The goal, when complete, will be to make accessible to such individuals the results of theoretically-based research that are of practical interest and utility in the analysis and prediction of operator workload in advanced and existing systems. In addition, the results of laboratory study focused on the development of a subjective rating technique for workload that is based on psychophysical scaling techniques are described.
Particle circulation and solids transport in large bubbling fluidized beds. Progress report
DOE Office of Scientific and Technical Information (OSTI.GOV)
Homsy, G.M.
1982-04-01
We have undertaken a theoretical study of the possibility of the formation of plumes or channeling when coal particles volatilize upon introduction to a fluidized bed, Fitzgerald (1980). We have completed the analysis of the basic state of uniform flow and are currently completing a stability analysis. We have modified the continuum equations of fluidization, Homsy et al. (1980), to include the source of gas due to volatilization, which we assume to be uniformly distributed spatially. Simplifying these equations and solving leads to the prediction of a basic state analogous to the state of uniform fluidization found when no sourcemore » is present within the medium. We are currently completing a stability analysis of this basic state which will give the critical volatilization rate above which the above simple basic state is unstable. Because of the experimental evidence of Jewett and Lawless (1981), who observed regularly spaced plume-like instabilities upon drying a bed of saturated silica gel, we are considering two-dimensional periodic disturbances. The analysis is similar to that given by Homsy, et al. (1980) and Medlin et al. (1974). We hope to determine the stability limits for this system shortly.« less
A Preliminary Analysis of the Theoretical Parameters of Organizaational Learning.
1995-09-01
PARAMETERS OF ORGANIZATIONAL LEARNING THESIS Presented to the Faculty of the Graduate School of Logistics and Acquisition Management of the Air...Organizational Learning Parameters in the Knowledge Acquisition Category 2~™ 2-3. Organizational Learning Parameters in the Information Distribution Category...Learning Refined Scale 4-94 4-145. Composition of Refined Scale 4 Knowledge Flow 4-95 4-146. Cronbach’s Alpha Statistics for the Complete Knowledge Flow
Jemmott, John B; Jemmott, Loretta Sweet; O'Leary, Ann; Icard, Larry D; Rutledge, Scott E; Stevens, Robin; Hsu, Janet; Stephens, Alisa J
2015-07-01
We examined the efficacy and mediation of Being Responsible for Ourselves (BRO), an HIV/STI risk-reduction intervention for African American men who have sex with men (MSM), the population with the highest HIV-diagnosis rate in the US. We randomized African American MSM to one of two interventions: BRO HIV/STI risk-reduction, targeting condom use; or attention-matched control, targeting physical activity and healthy diet. The interventions were based on social cognitive theory, the reasoned-action approach, and qualitative research. Men reporting anal intercourse with other men in the past 90 days were eligible and completed pre-intervention, immediately post-intervention, and 6 and 12 months post-intervention surveys. Of 595 participants, 503 (85 %) completed the 12-month follow-up. Generalized-estimating-equations analysis indicated that, compared with the attention-matched control intervention, the BRO intervention did not increase consistent condom use averaged over the 6- and 12-month follow-ups, which was the primary outcome. Although BRO did not affect the proportion of condom-protected intercourse acts, unprotected sexual intercourse, multiple partners, or insertive anal intercourse, it did reduce receptive anal intercourse compared with the control, a behavior linked to incident HIV infection. Mediation analysis using the product-of-coefficients approach revealed that although BRO increased seven of nine theoretical constructs it was designed to affect, it increased only one of three theoretical constructs that predicted consistent condom use: condom-use impulse-control self-efficacy. Thus, BRO indirectly increased consistent condom use through condom-use impulse-control self-efficacy. In conclusion, although BRO increased several theoretical constructs, most of those constructs did not predict consistent condom use; hence, the intervention did not increase it. Theoretical constructs that interventions should target to increase African American MSM's condom use are discussed.
Two-step complete polarization logic Bell-state analysis.
Sheng, Yu-Bo; Zhou, Lan
2015-08-26
The Bell state plays a significant role in the fundamental tests of quantum mechanics, such as the nonlocality of the quantum world. The Bell-state analysis is of vice importance in quantum communication. Existing Bell-state analysis protocols usually focus on the Bell-state encoding in the physical qubit directly. In this paper, we will describe an alternative approach to realize the near complete logic Bell-state analysis for the polarized concatenated Greenberger-Horne-Zeilinger (C-GHZ) state with two logic qubits. We show that the logic Bell-state can be distinguished in two steps with the help of the parity-check measurement (PCM) constructed by the cross-Kerr nonlinearity. This approach can be also used to distinguish arbitrary C-GHZ state with N logic qubits. As both the recent theoretical and experiment work showed that the C-GHZ state has its robust feature in practical noisy environment, this protocol may be useful in future long-distance quantum communication based on the logic-qubit entanglement.
K-theoretic Gromov-Witten invariants in genus 0 and integrable hierarchies
NASA Astrophysics Data System (ADS)
Milanov, Todor; Tonita, Valentin
2018-06-01
We prove that the genus 0 invariants in K-theoretic Gromov-Witten theory are governed by an integrable hierarchy of hydrodynamic type. If the K-theoretic quantum product is semisimple, then we also prove the completeness of the hierarchy.
NASA Astrophysics Data System (ADS)
Prasai, Binay; Wilson, A. R.; Wiley, B. J.; Ren, Y.; Petkov, Valeri
2015-10-01
The extent to which current theoretical modeling alone can reveal real-world metallic nanoparticles (NPs) at the atomic level was scrutinized and demonstrated to be insufficient and how it can be improved by using a pragmatic approach involving straightforward experiments is shown. In particular, 4 to 6 nm in size silica supported Au100-xPdx (x = 30, 46 and 58) explored for catalytic applications is characterized structurally by total scattering experiments including high-energy synchrotron X-ray diffraction (XRD) coupled to atomic pair distribution function (PDF) analysis. Atomic-level models for the NPs are built by molecular dynamics simulations based on the archetypal for current theoretical modeling Sutton-Chen (SC) method. Models are matched against independent experimental data and are demonstrated to be inaccurate unless their theoretical foundation, i.e. the SC method, is supplemented with basic yet crucial information on the length and strength of metal-to-metal bonds and, when necessary, structural disorder in the actual NPs studied. An atomic PDF-based approach for accessing such information and implementing it in theoretical modeling is put forward. For completeness, the approach is concisely demonstrated on 15 nm in size water-dispersed Au particles explored for bio-medical applications and 16 nm in size hexane-dispersed Fe48Pd52 particles explored for magnetic applications as well. It is argued that when ``tuned up'' against experiments relevant to metals and alloys confined to nanoscale dimensions, such as total scattering coupled to atomic PDF analysis, rather than by mere intuition and/or against data for the respective solids, atomic-level theoretical modeling can provide a sound understanding of the synthesis-structure-property relationships in real-world metallic NPs. Ultimately this can help advance nanoscience and technology a step closer to producing metallic NPs by rational design.The extent to which current theoretical modeling alone can reveal real-world metallic nanoparticles (NPs) at the atomic level was scrutinized and demonstrated to be insufficient and how it can be improved by using a pragmatic approach involving straightforward experiments is shown. In particular, 4 to 6 nm in size silica supported Au100-xPdx (x = 30, 46 and 58) explored for catalytic applications is characterized structurally by total scattering experiments including high-energy synchrotron X-ray diffraction (XRD) coupled to atomic pair distribution function (PDF) analysis. Atomic-level models for the NPs are built by molecular dynamics simulations based on the archetypal for current theoretical modeling Sutton-Chen (SC) method. Models are matched against independent experimental data and are demonstrated to be inaccurate unless their theoretical foundation, i.e. the SC method, is supplemented with basic yet crucial information on the length and strength of metal-to-metal bonds and, when necessary, structural disorder in the actual NPs studied. An atomic PDF-based approach for accessing such information and implementing it in theoretical modeling is put forward. For completeness, the approach is concisely demonstrated on 15 nm in size water-dispersed Au particles explored for bio-medical applications and 16 nm in size hexane-dispersed Fe48Pd52 particles explored for magnetic applications as well. It is argued that when ``tuned up'' against experiments relevant to metals and alloys confined to nanoscale dimensions, such as total scattering coupled to atomic PDF analysis, rather than by mere intuition and/or against data for the respective solids, atomic-level theoretical modeling can provide a sound understanding of the synthesis-structure-property relationships in real-world metallic NPs. Ultimately this can help advance nanoscience and technology a step closer to producing metallic NPs by rational design. Electronic supplementary information (ESI) available: XRD patterns, TEM and 3D structure modelling methodology. See DOI: 10.1039/c5nr04678e
Computational control of flexible aerospace systems
NASA Technical Reports Server (NTRS)
Sharpe, Lonnie, Jr.; Shen, Ji Yao
1994-01-01
The main objective of this project is to establish a distributed parameter modeling technique for structural analysis, parameter estimation, vibration suppression and control synthesis of large flexible aerospace structures. This report concentrates on the research outputs produced in the last two years. The main accomplishments can be summarized as follows. A new version of the PDEMOD Code had been completed based on several incomplete versions. The verification of the code had been conducted by comparing the results with those examples for which the exact theoretical solutions can be obtained. The theoretical background of the package and the verification examples has been reported in a technical paper submitted to the Joint Applied Mechanics & Material Conference, ASME. A brief USER'S MANUAL had been compiled, which includes three parts: (1) Input data preparation; (2) Explanation of the Subroutines; and (3) Specification of control variables. Meanwhile, a theoretical investigation of the NASA MSFC two-dimensional ground-based manipulator facility by using distributed parameter modeling technique has been conducted. A new mathematical treatment for dynamic analysis and control of large flexible manipulator systems has been conceived, which may provide an embryonic form of a more sophisticated mathematical model for future modified versions of the PDEMOD Codes.
Chaos in nuclei: Theory and experiment
NASA Astrophysics Data System (ADS)
Muñoz, L.; Molina, R. A.; Gómez, J. M. G.
2018-05-01
During the last three decades the quest for chaos in nuclei has been quite intensive, both with theoretical calculations using nuclear models and with detailed analyses of experimental data. In this paper we outline the concept and characteristics of quantum chaos in two different approaches, the random matrix theory fluctuations and the time series fluctuations. Then we discuss the theoretical and experimental evidence of chaos in nuclei. Theoretical calculations, especially shell-model calculations, have shown a strongly chaotic behavior of bound states in regions of high level density. The analysis of experimental data has shown a strongly chaotic behavior of nuclear resonances just above the one-nucleon emission threshold. For bound states, combining experimental data of a large number of nuclei, a tendency towards chaotic motion is observed in spherical nuclei, while deformed nuclei exhibit a more regular behavior associated to the collective motion. On the other hand, it had never been possible to observe chaos in the experimental bound energy levels of any single nucleus. However, the complete experimental spectrum of the first 151 states up to excitation energies of 6.20 MeV in the 208Pb nucleus have been recently identified and the analysis of its spectral fluctuations clearly shows the existence of chaotic motion.
NASA Astrophysics Data System (ADS)
Davies, Christine; Harrison, Judd; Lepage, G. Peter; Monahan, Christopher; Shigemitsu, Junko; Wingate, Matthew
2018-03-01
We present lattice QCD results for the matrix elements of R2 and other dimension-7, ΔB = 2 operators relevant for calculations of Δs, the Bs - B̅s width difference. We have computed correlation functions using 5 ensembles of the MILC Collaboration's 2+1 + 1-flavour gauge field configurations, spanning 3 lattice spacings and light sea quarks masses down to the physical point. The HISQ action is used for the valence strange quarks, and the NRQCD action is used for the bottom quarks. Once our analysis is complete, the theoretical uncertainty in the Standard Model prediction for ΔΓs will be substantially reduced.
A Study of Wind Turbine Comprehensive Operational Assessment Model Based on EM-PCA Algorithm
NASA Astrophysics Data System (ADS)
Zhou, Minqiang; Xu, Bin; Zhan, Yangyan; Ren, Danyuan; Liu, Dexing
2018-01-01
To assess wind turbine performance accurately and provide theoretical basis for wind farm management, a hybrid assessment model based on Entropy Method and Principle Component Analysis (EM-PCA) was established, which took most factors of operational performance into consideration and reach to a comprehensive result. To verify the model, six wind turbines were chosen as the research objects, the ranking obtained by the method proposed in the paper were 4#>6#>1#>5#>2#>3#, which are completely in conformity with the theoretical ranking, which indicates that the reliability and effectiveness of the EM-PCA method are high. The method could give guidance for processing unit state comparison among different units and launching wind farm operational assessment.
Analysis of Ward identities in supersymmetric Yang-Mills theory
NASA Astrophysics Data System (ADS)
Ali, Sajid; Bergner, Georg; Gerber, Henning; Montvay, Istvan; Münster, Gernot; Piemonte, Stefano; Scior, Philipp
2018-05-01
In numerical investigations of supersymmetric Yang-Mills theory on a lattice, the supersymmetric Ward identities are valuable for finding the critical value of the hopping parameter and for examining the size of supersymmetry breaking by the lattice discretisation. In this article we present an improved method for the numerical analysis of supersymmetric Ward identities, which takes into account the correlations between the various observables involved. We present the first complete analysis of supersymmetric Ward identities in N=1 supersymmetric Yang-Mills theory with gauge group SU(3). The results indicate that lattice artefacts scale to zero as O(a^2) towards the continuum limit in agreement with theoretical expectations.
The sustainability of healthcare innovations: a concept analysis.
Fleiszer, Andrea R; Semenic, Sonia E; Ritchie, Judith A; Richer, Marie-Claire; Denis, Jean-Louis
2015-07-01
To report on an analysis of the concept of the sustainability of healthcare innovations. While there have been significant empirical, theoretical and practical contributions made towards the development and implementation of healthcare innovations, there has been less attention paid to their sustainability. Yet many desired healthcare innovations are not sustained over the long term. There is a need to increase clarity around the concept of innovation sustainability to guide the advancement of knowledge on this topic. Concept analysis. We included literature reviews, theoretical and empirical articles, books and grey literature obtained through database searching (ABI/INFORM, Academic Search Complete, Business Source Complete, CINAHL, Embase, MEDLINE and Web of Science) from 1996-May 2014, reference harvesting and citation searching. We examined sources according to terms and definitions, characteristics, preconditions, outcomes and boundaries to evaluate the maturity of the concept. This concept is partially mature. Healthcare innovation sustainability remains a multi-dimensional, multi-factorial notion that is used inconsistently or ambiguously and takes on different meanings at different times in different contexts. We propose a broad conceptualization that consists of three characteristics: benefits, routinization or institutionalization, and development. We also suggest that sustained innovations are influenced by a variety of preconditions or factors, which are innovation-, context-, leadership- and process-related. Further conceptual development is essential to continue advancing our understanding of the sustainability of healthcare innovations, especially in nursing where this topic remains largely unexplored. © 2015 John Wiley & Sons Ltd.
A Stakeholder Analysis of the Navy’s Thirty-Year Shipbuilding Plan
2007-12-01
new.items/d05183.pdf Mankiw , N. Gregory (2004). Principles of economics (3rd ed.). Mason, OH: Thomson South-Western. McCaffery, J.L. and Jones, L.R...Shipbuilding Association, 2007). 11 III. LITERATURE REVIEW AND THEORETICAL FRAMEWORK Stakeholder theory confronts the traditional economic model of the... Mankiw , 2004). By completing these steps, the manager attains answers to basic questions about the stakeholder (Freeman, 1984): Over the long run
Heuristic approach to capillary pressures averaging
DOE Office of Scientific and Technical Information (OSTI.GOV)
Coca, B.P.
1980-10-01
Several methods are available to average capillary pressure curves. Among these are the J-curve and regression equations of the wetting-fluid saturation in porosity and permeability (capillary pressure held constant). While the regression equation seem completely empiric, the J-curve method seems to be theoretically sound due to its expression based on a relation between the average capillary radius and the permeability-porosity ratio. An analysis is given of each of these methods.
Theoretical study of local structure for Ni2+ ions at tetragonal sites in K2ZnF4:Ni2+ system.
Wang, Su-Juan; Kuang, Xiao-Yu; Lu, Cheng
2008-12-15
A theoretical method for studying the local lattice structure of Ni2+ ions in (NiF6)(4-) coordination complex is presented. Using the ligand-field model, the formulas relating the microscopic spin Hamiltonian parameters with the crystal structure parameters are derived. Based on the theoretical formulas, the 45 x 45 complete energy matrices for d8 (d2) configuration ions in a tetragonal ligand-field are constructed. By diagonalizing the complete energy matrices, the local distortion structure parameters (R perpendicular and R || ) of Ni2+ ions in K2ZnF4:Ni2+ system have been investigated. The theoretical results are accorded well with the experimental values. Moreover, to understand the detailed physical and chemical properties of the fluoroperovskite crystals, the theoretical values of the g factor of K2ZnF4:Ni2+ system at 78 and 290 K are reported first.
Theoretical study of local structure for Ni 2+ ions at tetragonal sites in K 2ZnF 4:Ni 2+ system
NASA Astrophysics Data System (ADS)
Wang, Su-Juan; Kuang, Xiao-Yu; Lu, Cheng
2008-12-01
A theoretical method for studying the local lattice structure of Ni 2+ ions in (NiF 6) 4- coordination complex is presented. Using the ligand-field model, the formulas relating the microscopic spin Hamiltonian parameters with the crystal structure parameters are derived. Based on the theoretical formulas, the 45 × 45 complete energy matrices for d8 ( d2) configuration ions in a tetragonal ligand-field are constructed. By diagonalizing the complete energy matrices, the local distortion structure parameters ( R⊥ and R||) of Ni 2+ ions in K 2ZnF 4:Ni 2+ system have been investigated. The theoretical results are accorded well with the experimental values. Moreover, to understand the detailed physical and chemical properties of the fluoroperovskite crystals, the theoretical values of the g factor of K 2ZnF 4:Ni 2+ system at 78 and 290 K are reported first.
Note: Eddy current displacement sensors independent of target conductivity.
Wang, Hongbo; Li, Wei; Feng, Zhihua
2015-01-01
Eddy current sensors (ECSs) are widely used for non-contact displacement measurement. In this note, the quantitative error of an ECS caused by target conductivity was analyzed using a complex image method. The response curves (L-x) of the ECS with different targets were similar and could be overlapped by shifting the curves on x direction with √2δ/2. Both finite element analysis and experiments match well with the theoretical analysis, which indicates that the measured error of high precision ECSs caused by target conductivity can be completely eliminated, and the ECSs can measure different materials precisely without calibration.
Acquisition and production of skilled behavior in dynamic decision-making tasks
NASA Technical Reports Server (NTRS)
Kirlik, Alex
1993-01-01
Summaries of the four projects completed during the performance of this research are included. The four projects described are: Perceptual Augmentation Aiding for Situation Assessment, Perceptual Augmentation Aiding for Dynamic Decision-Making and Control, Action Advisory Aiding for Dynamic Decision-Making and Control, and Display Design to Support Time-Constrained Route Optimization. Papers based on each of these projects are currently in preparation. The theoretical framework upon which the first three projects are based, Ecological Task Analysis, was also developed during the performance of this research, and is described in a previous report. A project concerned with modeling strategies in human control of a dynamic system was also completed during the performance of this research.
Dreuw, Andreas
2006-11-13
With the advent of modern computers and advances in the development of efficient quantum chemical computer codes, the meaningful computation of large molecular systems at a quantum mechanical level became feasible. Recent experimental effort to understand photoinitiated processes in biological systems, for instance photosynthesis or vision, at a molecular level also triggered theoretical investigations in this field. In this Minireview, standard quantum chemical methods are presented that are applicable and recently used for the calculation of excited states of photoinitiated processes in biological molecular systems. These methods comprise configuration interaction singles, the complete active space self-consistent field method, and time-dependent density functional theory and its variants. Semiempirical approaches are also covered. Their basic theoretical concepts and mathematical equations are briefly outlined, and their properties and limitations are discussed. Recent successful applications of the methods to photoinitiated processes in biological systems are described and theoretical tools for the analysis of excited states are presented.
Development of the Environmental Technical Information System
1975-04-01
official Department oi the Army position, unless so designated by other authorized documents. «CC:,;!;I?N tw HIS . ■ " ftIM B c ii a UN, " □ j...regulations that may concern the Army. CHLUS is complete tor six states and lor areas ot federal jurisdiction, and datu tor another ten stales are...Theoretical Analysis 20 Isolating The Export Industries: Direct Methods Description of the Models 24 Economic Impact on Local Businesses Change in
The Past, Present, and Future of Auger Lineshape Analysis
1991-01-01
Theoretical study of the application of positron induced Auger electron spectroscopy, Phys. Rev. B41, 3928, 1990. 295. Schultz,.P.J. and Lynn. K.G...system. The line shapes most heavily studied over the years include those of the low Z metals (e.g. Be. Li, Na. Mg. and Al), those of C and Si, and of...background signal. fuggle Two new experimental approaches almost completely eliminate the Ramaker 9 background. In one method, low energy positrons are
Some new aspects on the superrotation of the thermosphere
NASA Technical Reports Server (NTRS)
Blum, P. W.; Harris, I.
1974-01-01
The motion of the thermosphere with a rotational velocity between 10 and 20 per cent in excess of the earth's rotational velocity has been deduced by King-Hele and his co-workers from the change of the inclination of satellite orbits. To date, no completely satisfactory explanation of the observations has been presented. In this paper, it is shown that in the thermosphere there exists a small diurnal mean driving force in the eastward direction. This force has not previously been considered in analyses of superrotation. A critical review of the observations and a theoretical analysis that takes account of both equinox and solstice conditions is presented. In the lower height region, where the great majority of observations were made, it is possible to achieve agreement between observations and a dynamical model. Additional observational data are needed in the isothermal region for a more complete analysis.
Electrochemical performance investigations on the hydrogen depolarized CO2 concentrator
NASA Technical Reports Server (NTRS)
Aylward, J. R.
1976-01-01
An extensive investigation of anode and cathode polarization in complete cells and half cells was conducted to determine the factors affecting HDC electrode polarization and the nature of this polarization. Matrix-electrolyte-electrode interactions and cell electrolyte composition were also investigated. The electrodes were found to have normal performance capabilities. The HDC anode polarization characteristics were correlated with a theoretical kinetic analysis; and, except for some quantitative details, a rather complete understanding of the causes for HDC electrode polarization was formulated. One of the important finding resulting from the kinetic analysis was that platinum appears to catalyze the decomposition of carbonic acid to carbon dioxide and water. It was concluded that the abnormal voltage performance of the One Man ARS HDC cells was caused by insufficient cell electrolyte volume under normal operating conditions due to deficiencies in the reservoir to cell interfacing.
Gajendran, Ravi S; Harrison, David A
2007-11-01
What are the positive and negative consequences of telecommuting? How do these consequences come about? When are these consequences more or less potent? The authors answer these questions through construction of a theoretical framework and meta-analysis of 46 studies in natural settings involving 12,883 employees. Telecommuting had small but mainly beneficial effects on proximal outcomes, such as perceived autonomy and (lower) work-family conflict. Importantly, telecommuting had no generally detrimental effects on the quality of workplace relationships. Telecommuting also had beneficial effects on more distal outcomes, such as job satisfaction, performance, turnover intent, and role stress. These beneficial consequences appeared to be at least partially mediated by perceived autonomy. Also, high-intensity telecommuting (more than 2.5 days a week) accentuated telecommuting's beneficial effects on work-family conflict but harmed relationships with coworkers. Results provide building blocks for a more complete theoretical and practical treatment of telecommuting. (c) 2007 APA
Synthesis, crystal growth, characterization and theoretical studies of 4-aminobenzophenonium picrate
NASA Astrophysics Data System (ADS)
Aditya Prasad, A.; Muthu, K.; Rajasekar, M.; Meenatchi, V.; Meenakshisundaram, S. P.
2015-01-01
Single crystals of 4-aminobenzophenonium picrate (4ABPP) were grown by slow evaporation of a mixed solvent system methanol-acetone (1:1,v/v) containing equimolar quantities of picric acid and 4-aminobenzophenone. The proton and carbon signals are confirmed by nuclear magnetic resonance spectroscopy. The various functional groups present in the molecule are identified by FT-IR analysis. Optimized geometry, first-order molecular hyperpolarizability (β), polarizability (α), bond length, bond angles and excited state energy from theoretical UV were derived by Hartree-Fock calculations. The complete assignment of the vibrational modes for 4-aminobenzophenonium picrate was performed by the scaled quantum mechanics force field (SQMFF) methodology using potential energy distribution. Natural bond orbital (NBO) calculations were employed to study the stabilities arising from charge delocalization and intermolecular interactions of 4ABPP. The atomic charge distributions of the various atoms present in 4ABPP are obtained by Mulliken charge population analysis. The as-grown crystal is further characterized by thermal and optical absorbance studies.
Theoretical analysis of factors controlling the nonalternating CO/C(2)H(4) copolymerization.
Haras, Alicja; Michalak, Artur; Rieger, Bernhard; Ziegler, Tom
2005-06-22
A [P-O]Pd catalyst based on o-alkoxy derivatives of diphenylphosphinobenzene sulfonic acid (I) has recently been shown by Drent et al. to perform nonalternating CO/C(2)H(4) copolymerization with subsequent incorporation of ethylene units into the polyketone chain. The origin of the nonalternation is investigated in a theoretical study of I, where calculated activation barriers and reaction heats of all involved elementary steps are used to generate a complete kinetic model. The kinetic model is able to account for the observed productivity and degree of nonalternation as a function of temperature. Consistent with the energy changes obtained for the real catalyst model, the selectivity toward a nonalternating distribution of both comonomers appears to be mainly a result of a strong destabilization of the Pd-acyl complex.
Microengineered open tubular columns for GC analysis
NASA Astrophysics Data System (ADS)
Wiranto, Goib; Haskard, Malcolm R.; Mulcahy, Dennis E.; Davey, David E.; Dawes, Ernest F.
1999-09-01
Microengineered open tubular (MOT) columns with semi rectangular cross-sections have been designed and fabricated using microengineering techniques. The creation of 100-micrometers wide, 20-micrometers deep, and 125-cm long columns employed isotropic etching on (100) silicon and anodic bonding with a Pyrex 7740 glass cover plate. Column geometry has been optimized to achieve maximum efficiency and allow extreme operating conditions. The walls of the microcolumns were coated with a non-polar liquid stationary phase. Performances of the MOT columns have been demonstrated by their ability to completely separate a series of hydrocarbon mixture in less than 1.25 min under isothermal condition of 150 degrees C. The achievable column efficiencies as measured in terms of theoretical plate height ranged from 0.57 to 1.45 mm, which agreed well with theoretical predictions.
Observed and theoretical variations of atmospheric ozone
NASA Technical Reports Server (NTRS)
London, J.
1976-01-01
Results are summarized from three areas of ozone research: (1) continued analysis of the global distribution of total ozone to extend the global ozone atlas to summarize 15 years (1957-72) of ground based observations; (2) analysis of balloon borne ozonesonde observations for Arosa, Switzerland, and Hohenpeissenberg, Germany (GFR); (3) contined processing of the (Orbiting Geophysical Observatory-4) satellite data to complete the analysis of the stratospheric ozone distribution from the available OGO-4 data. Results of the analysis of the total ozone observations indicated that the long term ozone variation have marked regional patterns and tend to alternate with season and hemisphere. It is becoming increasingly clear that these long period changes are associated with large scale variations in the general upper atmosphere circulation patterns.
X-ray Characterization and Defect Control of III-Nitrides
NASA Astrophysics Data System (ADS)
Tweedie, James
A process for controlling point defects in a semiconductor using excess charge carriers was developed in theory and practice. A theoretical framework based on first principles was developed to model the effect of excess charge carriers on the formation energy and concentration of charged point defects in a semiconductor. The framework was validated for the completely general case of a generic carrier source and a generic point defect in a generic semiconductor, and then refined for the more specific case of a generic carrier source applied during the growth of a doped semiconductor crystal. It was theoretically demonstrated that the process as defined will always reduce the degree of compensation in the semiconductor. The established theoretical framework was applied to the case of above-bandgap illumination on both the MOCVD growth and the post-growth annealing of Mg-doped GaN thin films. It was theoretically demonstrated that UV light will lower the concentration of compensating defects during growth and will facilitate complete activation of the Mg acceptor at lower annealing temperatures. Annealing experiments demonstrated that UV illumination of GaN:Mg thin films during annealing lowers the resistivity of the film at any given temperature below the 650 °C threshold at which complete activation is achieved without illumination. Broad spectrum analysis of the photoluminescence (PL) spectra together with a correlation between the acceptor-bound exciton transition and room temperature resistivity demonstrated that UV light only acts to enhance the activation Mg. Surface chemistry and interface chemistry of AlN and high Al mole fraction AlGaN films were studied using x-ray photoelectron spectroscopy (XPS). It was seen that surfaces readily form stable surface oxides. The Schottky barrier height (SBH) of various metals contacted to these surfaces was using XPS. Finally, an x-ray diffraction method (XRD) was developed to quantify strain and composition of alloy films in the context of a processing environment. Reciprocal space mapping revealed intensity limitations on the accuracy of the method. The method was used to demonstrate a bimodal strain distribution across the composition spectrum for 200 nm AlGaN thin films grown on GaN. A weak, linear strain dependence on composition was observed for Al mole fractions below 30%. Above this threshold the films were observed to be completely relaxed by cracking.
Senthil kumar, J; Jeyavijayan, S; Arivazhagan, M
2015-02-05
The FT-IR and FT-Raman spectra of 3,5-dichlorobenzonitrile and m-bromobenzonitrile have been recorded in the region 4000-400 cm(-1) and 3500-50 cm(-1), respectively. The optimized geometry, wave numbers and intensity of vibrational bonds of title molecules are obtained by ab initio and DFT level of theory with complete relaxation in the potential energy surface using 6-311++G(d, p) basis set. A complete vibrational assignments aided by the theoretical harmonic frequency, analysis have been proposed. The harmonic vibrational frequencies calculated have been compared with experimental FT-IR and FT-Raman spectra. The observed and calculated frequencies are found to be in good agreement. Stability of the molecule arising from hyperconjugative interactions, charge delocalization have been analyzed using natural bond orbital (NBO) analysis. The UV-Vis spectral analysis of the molecules has also been done which confirms the charge transfer of the molecules. Furthermore, the first hyperpolarizability and total dipole moment of the molecules have been calculated. Copyright © 2014 Elsevier B.V. All rights reserved.
Vella, L R; Butterworth, R E; Johnson, R; Law, G Urquhart
2015-11-01
Empirical evidence suggests that the Solihull Approach parenting group, 'Understanding Your Child's Behaviour' (UYCB), can improve child behaviour and parental well-being. However, little is known about parents' in-depth experience of participating in the UYCB programme. This study provides an in-depth qualitative evaluation of UYCB, focussing on possible moderating factors and mechanisms of change that may inform programme development. Ten parents (eight mothers and two fathers), recruited from seven UYCB groups across two locations, were interviewed within 7 weeks of completing the group and again 10 months later. Data were analysed using interpretative phenomenological analysis. Four themes were identified: 'Two Tiers of Satisfaction', 'Development as a Parent', 'Improved Self-belief' and 'The "Matthew Effect"'. In summary, the majority of parents were immensely satisfied at both completion and follow-up: they valued an experience of containment and social support and perceived improvement in specific child difficulties, their experience of parenting, their confidence and their coping. Most parents appeared to have developed more reflective and empathic parenting styles, with self-reported improved behaviour management. Theoretical material was well received, although some struggled with technical language. Positive outcomes appeared to be maintained, even reinforced, at follow-up, and were associated with having few initial child difficulties, perceiving improvement at completion and persevering with the recommendations. Two participants, whose children had the most severe difficulties, perceived deterioration and felt that the group was insufficient for their level of difficulties. Through in-depth analysis of parental experiences, UYCB appears to achieve its aims and communicate well its theoretical principles, although change may also occur through processes common to other group programmes (e.g. social support). Recommendations, stemming from the experiences of these parents, include simplified language, separate groups for parents with complex needs, greater emphasis on the importance of perseverance, and additional support for parents who appear to be struggling to make changes. © 2015 John Wiley & Sons Ltd.
NASA Astrophysics Data System (ADS)
Vargas-Magaña, Mariana; Ho, Shirley; Cuesta, Antonio J.; O'Connell, Ross; Ross, Ashley J.; Eisenstein, Daniel J.; Percival, Will J.; Grieb, Jan Niklas; Sánchez, Ariel G.; Tinker, Jeremy L.; Tojeiro, Rita; Beutler, Florian; Chuang, Chia-Hsun; Kitaura, Francisco-Shu; Prada, Francisco; Rodríguez-Torres, Sergio A.; Rossi, Graziano; Seo, Hee-Jong; Brownstein, Joel R.; Olmstead, Matthew; Thomas, Daniel
2018-06-01
We investigate the potential sources of theoretical systematics in the anisotropic Baryon Acoustic Oscillation (BAO) distance scale measurements from the clustering of galaxies in configuration space using the final Data Release (DR12) of the Baryon Oscillation Spectroscopic Survey (BOSS). We perform a detailed study of the impact on BAO measurements from choices in the methodology such as fiducial cosmology, clustering estimators, random catalogues, fitting templates, and covariance matrices. The theoretical systematic uncertainties in BAO parameters are found to be 0.002 in the isotropic dilation α and 0.003 in the quadrupolar dilation ɛ. The leading source of systematic uncertainty is related to the reconstruction techniques. Theoretical uncertainties are sub-dominant compared with the statistical uncertainties for BOSS survey, accounting 0.2σstat for α and 0.25σstat for ɛ (σα, stat ˜ 0.010 and σɛ, stat ˜ 0.012, respectively). We also present BAO-only distance scale constraints from the anisotropic analysis of the correlation function. Our constraints on the angular diameter distance DA(z) and the Hubble parameter H(z), including both statistical and theoretical systematic uncertainties, are 1.5 per cent and 2.8 per cent at zeff = 0.38, 1.4 per cent and 2.4 per cent at zeff = 0.51, and 1.7 per cent and 2.6 per cent at zeff = 0.61. This paper is part of a set that analyses the final galaxy clustering data set from BOSS. The measurements and likelihoods presented here are cross-checked with other BAO analysis in Alam et al. The systematic error budget concerning the methodology on post-reconstruction BAO analysis presented here is used in Alam et al. to produce the final cosmological constraints from BOSS.
Combine experimental and theoretical investigation on an alkaloid-Dimethylisoborreverine
NASA Astrophysics Data System (ADS)
Singh, Swapnil; Singh, Harshita; Karthick, T.; Agarwal, Parag; Erande, Rohan D.; Dethe, Dattatraya H.; Tandon, Poonam
2016-01-01
A combined experimental (FT-IR, 1H and 13C NMR) and theoretical approach is used to study the structure and properties of antimalarial drug dimethylisoborreverine (DMIB). Conformational analysis, has been performed by plotting one dimensional potential energy curve that was computed using density functional theory (DFT) with B3LYP/6-31G method and predicted conformer A1 as the most stable conformer. After full geometry optimization, harmonic wavenumbers were computed for conformer A1 at the DFT/B3LYP/6-311++G(d,P) level. A complete vibrational assignment of all the vibrational modes have been performed on the bases of the potential energy distribution (PED) and theoretical results were found to be in good agreement with the observed data. To predict the solvent effect, the UV-Vis spectra were calculated in different solvents by polarizable continuum model using TD-DFT method. Molecular docking studies were performed to test the biological activity of the sample using SWISSDOCK web server and Hex 8.0.0 software. The molecular electrostatic potential (MESP) was plotted to identify the reactive sites of the molecule. Natural bond orbital (NBO) analysis was performed to get a deep insight of intramolecular charge transfer. Thermodynamical parameters were calculated to predict the direction of chemical reaction.
Hydrostatic paradox: experimental verification of pressure equilibrium
NASA Astrophysics Data System (ADS)
Kodejška, Č.; Ganci, S.; Říha, J.; Sedláčková, H.
2017-11-01
This work is focused on the experimental verification of the balance between the atmospheric pressure acting on the sheet of paper, which encloses the cylinder completely or partially filled with water from below, where the hydrostatic pressure of the water column acts against the atmospheric pressure. First of all this paper solves a theoretical analysis of the problem, which is based, firstly, on the equation for isothermal process and, secondly, on the equality of pressures inside and outside the cylinder. From the measured values the confirmation of the theoretical quadratic dependence of the air pressure inside the cylinder on the level of the liquid in the cylinder is obtained, the maximum change in the volume of air within the cylinder occurs for the height of the water column L of one half of the total height of the vessel H. The measurements were made for different diameters of the cylinder and with plates made of different materials located at the bottom of the cylinder to prevent liquid from flowing out of the cylinder. The measured values were subjected to statistical analysis, which demonstrated the validity of the zero hypothesis, i.e. that the measured values are not statistically significantly different from the theoretically calculated ones at the statistical significance level α = 0.05.
[Sequencing and analysis of the complete genome of a rabies virus isolate from Sika deer].
Zhao, Yun-Jiao; Guo, Li; Huang, Ying; Zhang, Li-Shi; Qian, Ai-Dong
2008-05-01
One DRV strain was isolated from Sika Deer brain and sequenced. Nine overlapped gene fragments were amplified by RT-PCR through 3'-RACE and 5'-RACE method, and the complete DRV genome sequence was assembled. The length of the complete genome is 11863bp. The DRV genome organization was similar to other rabies viruses which were composed of five genes and the initiation sites and termination sites were highly conservative. There were mutated amino acids in important antigen sites of nucleoprotein and glycoprotein. The nucleotide and amino acid homologies of gene N, P, M, G, L in strains with completed genomie sequencing were compared. Compared with N gene sequence of other typical rabies viruses, a phylogenetic tree was established . These results indicated that DRV belonged to gene type 1. The highest homology compared with Chinese vaccine strain 3aG was 94%, and the lowest was 71% compared with WCBV. These findings provided theoretical reference for further research in rabies virus.
1980-07-01
thin bars are extended. The complete solution is presented in graphs for the use of designers . The theoretical development is correlated with experiments...The concept of "coefficient of efficiency" is introduced to evaluate the degree of optimization. An ideal design of the inside boundary of a tube...efficiency coefficient is increased from 0.59 to 0.95. Tests with a brittle material show an increase in strength of 20Z. An ideal design of the boundary of
Experimental data and theoretical analysis of an operating 100 kW wind turbine
NASA Technical Reports Server (NTRS)
Linscott, B. S.; Glasgow, J. C.; Anderson, W. D.; Donham, R. E.
1978-01-01
Experimental test data are correlated with analyses of turbine loads and complete system behavior of the ERDA-NASA 100 kW Mod-0 wind turbine generator over a broad range of steady state conditions, as well as during transient conditions. The deficit in the ambient wind field due to the upwind tower turbine support structure is found to be very significant in exciting higher harmonic loads associated with the flapping response of the blade in bending.
NASA Astrophysics Data System (ADS)
Förtsch, Christian; Dorfner, Tobias; Baumgartner, Julia; Werner, Sonja; von Kotzebue, Lena; Neuhaus, Birgit J.
2018-04-01
The German National Education Standards (NES) for biology were introduced in 2005. The content part of the NES emphasizes fostering conceptual knowledge. However, there are hardly any indications of what such an instructional implementation could look like. We introduce a theoretical framework of an instructional approach to foster students' conceptual knowledge as demanded in the NES (Fostering Conceptual Knowledge) including instructional practices derived from research on single core ideas, general psychological theories, and biology-specific features of instructional quality. First, we aimed to develop a rating manual, which is based on this theoretical framework. Second, we wanted to describe current German biology instruction according to this approach and to quantitatively analyze its effectiveness. And third, we aimed to provide qualitative examples of this approach to triangulate our findings. In a first step, we developed a theoretically devised rating manual to measure Fostering Conceptual Knowledge in videotaped lessons. Data for quantitative analysis included 81 videotaped biology lessons of 28 biology teachers from different German secondary schools. Six hundred forty students completed a questionnaire on their situational interest after each lesson and an achievement test. Results from multilevel modeling showed significant positive effects of Fostering Conceptual Knowledge on students' achievement and situational interest. For qualitative analysis, we contrasted instruction of four teachers, two with high and two with low student achievement and situational interest using the qualitative method of thematic analysis. Qualitative analysis revealed five main characteristics describing Fostering Conceptual Knowledge. Therefore, implementing Fostering Conceptual Knowledge in biology instruction seems promising. Examples of how to implement Fostering Conceptual Knowledge in instruction are shown and discussed.
NASA Astrophysics Data System (ADS)
Giardina, G.; Mandaglio, G.; Nasirov, A. K.; Anastasi, A.; Curciarello, F.; Fazio, G.
2018-05-01
The sensitivity of reaction mechanism in the formation of compound nucleus (CN) by the analysis of kinetic energy spectra of light particles and of reaction products are shown. The dependence of the P CN fusion probability of reactants and W sur survival probability of CN against fission at its deexcitation on the mass and charge symmetries in the entrance channel of heavy-ion collisions, as well as on the neutron numbers is discussed. The possibility of conducting a complex program of investigations of the complete fusion by reliable ways depends on the detailed and refined methods of experimental and theoretical analyses.
Hagemeier, Nicholas E; Murawski, Matthew M
2014-02-12
To develop and validate an instrument to assess subjective ratings of the perceived value of various postgraduate training paths followed using expectancy-value as a theoretical framework; and to explore differences in value beliefs across type of postgraduate training pursued and type of pharmacy training completed prior to postgraduate training. A survey instrument was developed to sample 4 theoretical domains of subjective task value: intrinsic value, attainment value, utility value, and perceived cost. Retrospective self-report methodology was employed to examine respondents' (N=1,148) subjective task value beliefs specific to their highest level of postgraduate training completed. Exploratory and confirmatory factor analytic techniques were used to evaluate and validate value belief constructs. Intrinsic, attainment, utility, cost, and financial value constructs resulted from exploratory factor analysis. Cross-validation resulted in a 26-item instrument that demonstrated good model fit. Differences in value beliefs were noted across type of postgraduate training pursued and pharmacy training characteristics. The Postgraduate Training Value Instrument demonstrated evidence of reliability and construct validity. The survey instrument can be used to assess value beliefs regarding multiple postgraduate training options in pharmacy and potentially inform targeted recruiting of individuals to those paths best matching their own value beliefs.
Prasai, Binay; Wilson, A R; Wiley, B J; Ren, Y; Petkov, Valeri
2015-11-14
The extent to which current theoretical modeling alone can reveal real-world metallic nanoparticles (NPs) at the atomic level was scrutinized and demonstrated to be insufficient and how it can be improved by using a pragmatic approach involving straightforward experiments is shown. In particular, 4 to 6 nm in size silica supported Au(100-x)Pd(x) (x = 30, 46 and 58) explored for catalytic applications is characterized structurally by total scattering experiments including high-energy synchrotron X-ray diffraction (XRD) coupled to atomic pair distribution function (PDF) analysis. Atomic-level models for the NPs are built by molecular dynamics simulations based on the archetypal for current theoretical modeling Sutton-Chen (SC) method. Models are matched against independent experimental data and are demonstrated to be inaccurate unless their theoretical foundation, i.e. the SC method, is supplemented with basic yet crucial information on the length and strength of metal-to-metal bonds and, when necessary, structural disorder in the actual NPs studied. An atomic PDF-based approach for accessing such information and implementing it in theoretical modeling is put forward. For completeness, the approach is concisely demonstrated on 15 nm in size water-dispersed Au particles explored for bio-medical applications and 16 nm in size hexane-dispersed Fe48Pd52 particles explored for magnetic applications as well. It is argued that when "tuned up" against experiments relevant to metals and alloys confined to nanoscale dimensions, such as total scattering coupled to atomic PDF analysis, rather than by mere intuition and/or against data for the respective solids, atomic-level theoretical modeling can provide a sound understanding of the synthesis-structure-property relationships in real-world metallic NPs. Ultimately this can help advance nanoscience and technology a step closer to producing metallic NPs by rational design.
Analysis of the DFP/AFCS Systems for Compensating Gravity Distortions on the 70-Meter Antenna
NASA Technical Reports Server (NTRS)
Imbriale, William A.; Hoppe, Daniel J.; Rochblatt, David
2000-01-01
This paper presents the theoretical computations showing the expected performances for both systems. The basic analysis tool is a Physical Optics reflector analysis code that was ported to a parallel computer for faster execution times. There are several steps involved in computing the RF performance of the various systems. 1 . A model of the RF distortions of the main reflector is required. This model is based upon measured holography maps of the 70-meter antenna obtained at 3 elevation angles. The holography maps are then processed (using an appropriate gravity mechanical model of the dish) to provide surface distortion maps at all elevation angles. 2. From the surface distortion maps, ray optics is used to determine the theoretical shape of the DFP that will exactly phase compensate the distortions. 3. From the theoretical shape and a NASTRAN mechanical model of the plate, the actuator positions that generate a surface that provides the best RMS fit to the theoretical model are selected. Using the actuator positions and the NASTRAN model provides an accurate description of the actual mirror shape. 4. Starting from the mechanical drawings of the feed, a computed RF feed pattern is generated. This pattern is expanded into a set of spherical wave modes so that a complete near field analysis of the reflector system can be obtained. 5. For the array feed, the excitation coefficients that provide the maximum gain are computed using a phase conjugate technique. The basic experimental geometry consisted of a dual shaped 70-meter antenna system; a refocusing ellipse, a DFP and an array feed system. To provide physical insight to the systems performance, focal plane field plots are presented at several elevations. Curves of predicted performance are shown for the DFP system, monopulse tracking system, AFCS and combined DFP/AFCS system. The calculated results show that the combined DFP/AFCS system is capable of recovering the majority of the gain lost due to gravity distortion.
Leyva-González, Félix Arturo; Leo-Amador, Guillermo Enrique; Viniegra-Velázquez, Leonardo; Degollado-Bardales, Lilia; Zavala-Arenas, Jesús Arturo; González-Cobos, Roberto Palemón; Valencia-Sánchez, Jesús Salvador; Leyva-Salas, César Arturo; Angulo-Bernal, Sonia Elizabeth; Gómez-Arteaga, Gress Marissell
2010-01-01
Determine what the relationship between participation in classroom of students attending courses at the Educational Research and Teacher Education (CIEFD's) and the development of proficiency in critical reading of theoretical texts in education. Intervention study, multicenter students (medical specialist) level Diploma in teaching methodology (DMDN) 1 and 2 (n=46 n=29) of the six CIEFD's (DF Siglo XXI, Mexico City La Raza, Nuevo Leon, Sonora, Puebla and Veracruz), period: March to August 2007 and a Masters in education (n=9, generation 2007-2008). Two instruments were constructed that evaluated the participation variables and critical reading of theoretical texts in education, conceptual validity; content and reliability were assessed by experts in education research. The educational intervention was in the form of seminars (three times a week in DMDN 1 and twice weekly in DMDN 2 and Masters). Participation was assessed halfway through the course and on completion, critical reading at the beginning as well as the end. Statistically significant associations were observed in DMDN 1 (four Centers) and the Masters, but not DMDN 2. In this investigation some of the theoretical proposals of the participatory education were recreated, starting from the analysis of our results. In some centers and in the masters, strengthening participation in this educational intervention is related to the development of critical reading of theoretical texts in education.
Solute Nucleation and Growth in Supercritical Fluid Mixtures
NASA Technical Reports Server (NTRS)
Smedley, Gregory T.; Wilemski, Gerald; Rawlins, W. Terry; Joshi, Prakash; Oakes, David B.; Durgin, William W.
1996-01-01
This research effort is directed toward two primary scientific objectives: (1) to determine the gravitational effect on the measurement of nucleation and growth rates near a critical point and (2) to investigate the nucleation process in supercritical fluids to aid in the evaluation and development of existing theoretical models and practical applications. A nucleation pulse method will be employed for this investigation using a rapid expansion to a supersaturated state that is maintained for approximately 1 ms followed by a rapid recompression to a less supersaturated state that effectively terminates nucleation while permitting growth to continue. Nucleation, which occurs during the initial supersaturated state, is decoupled from growth by producing rapid pressure changes. Thermodynamic analysis, condensation modeling, apparatus design, and optical diagnostic design necessary for the initiation of a theoretical and experimental investigation of naphthalene nucleation from supercritical CO2 have been completed.
The group discussion effect: integrative processes and suggestions for implementation.
Meleady, Rose; Hopthrow, Tim; Crisp, Richard J
2013-02-01
One of the most consistent findings in experimental social dilemmas research is the positive effect group discussion has on cooperative behavior. At a time when cooperation and consensus is critical to tackle global problems, ranging from debt to deforestation, understanding the dynamics of group discussion is a pressing need. Unfortunately, research investigating the underlying processes and implementation of the effect has been inconclusive. The authors present a critical review of existing explanations and integrate these perspectives into a single process model of group discussion, providing a more complete theoretical picture of how interrelated factors combine to facilitate discussion-induced cooperation. On the basis of this theoretical analysis, they consider complimentary approaches to the indirect and feasible implementation of group discussion. They argue that such strategies may overcome the barriers to direct discussion observed across a range of groups and organizations.
Communication: Electron ionization of DNA bases.
Rahman, M A; Krishnakumar, E
2016-04-28
No reliable experimental data exist for the partial and total electron ionization cross sections for DNA bases, which are very crucial for modeling radiation damage in genetic material of living cell. We have measured a complete set of absolute partial electron ionization cross sections up to 500 eV for DNA bases for the first time by using the relative flow technique. These partial cross sections are summed to obtain total ion cross sections for all the four bases and are compared with the existing theoretical calculations and the only set of measured absolute cross sections. Our measurements clearly resolve the existing discrepancy between the theoretical and experimental results, thereby providing for the first time reliable numbers for partial and total ion cross sections for these molecules. The results on fragmentation analysis of adenine supports the theory of its formation in space.
Theoretical and material studies on thin-film electroluminescent devices
NASA Technical Reports Server (NTRS)
Summers, C. J.; Goldman, J. A.; Brennan, K.
1988-01-01
During this report period work was performed on the modeling of High Field Electronic Transport in Bulk ZnS and ZnSe, and also on the surface cleaning of Si for MBE growth. Some MBE growth runs have also been performed in the Varian GEN II System. A brief outline of the experimental work is given. A complete summary will be done at the end of the next reporting period at the completion of the investigation. The theoretical studies are included.
Neutron beam measurement of industrial polymer materials for composition and bulk integrity
NASA Astrophysics Data System (ADS)
Rogante, M.; Rosta, L.; Heaton, M. E.
2013-10-01
Neutron beam techniques, among other non-destructive diagnostics, are particularly irreplaceable in the complete analysis of industrial materials and components when supplying fundamental information. In this paper, nanoscale small-angle neutron scattering analysis and prompt gamma activation analysis for the characterization of industrial polymers are considered. The basic theoretical aspects are briefly introduced and some applications are presented. The investigations of the SU-8 polymer in axial airflow microturbines—i.e. microelectromechanical systems—are presented foremost. Also presented are full and feasibility studies on polyurethanes, composites based on cross-linked polymers reinforced by carbon fibres and polymer cement concrete. The obtained results have provided a substantial contribution to the improvement of the considered materials, and indeed confirmed the industrial applicability of the adopted techniques in the analysis of polymers.
NASA Astrophysics Data System (ADS)
Borah, Mukunda Madhab; Devi, Th. Gomti
2017-05-01
In the present work, L-phenylalanine is studied using the experimental and theoretical methods. The spectral characterization of the molecule has been done using Raman, FTIR, Hartee-Fock(HF), density functional theory (DFT) and vibrational energy distribution analysis (VEDA) calculation. The optimization of the molecule has been studied using basis set HF/6-31G(d,p) and B3LYP/6-31G(d,p) for Hartree Fock and density functional theory calculation. The complete vibrational assignment of the molecule in monomer and dimer states have been attempted. The potential energy distribution and normal mode analysis are also carried out to determine the contributions of bond oscillators in each normal mode. The molecular geometry, HOMO-LUMO energy gap, molecular hardness (η), ionization energy (IE), electron affinity (EA), total energy and dipole moment were determined from the calculated data. The observed experimental and the scaled theoretical results are compared and found to be in good agreement. The vibrational assignment of molecule in different dimer states has also been done using SERS data and better correlated Raman peaks are observed as compare to normal Raman technique.
NASA Technical Reports Server (NTRS)
Baker, A. J.; Orzechowski, J. A.
1980-01-01
A theoretical analysis is presented yielding sets of partial differential equations for determination of turbulent aerodynamic flowfields in the vicinity of an airfoil trailing edge. A four phase interaction algorithm is derived to complete the analysis. Following input, the first computational phase is an elementary viscous corrected two dimensional potential flow solution yielding an estimate of the inviscid-flow induced pressure distribution. Phase C involves solution of the turbulent two dimensional boundary layer equations over the trailing edge, with transition to a two dimensional parabolic Navier-Stokes equation system describing the near-wake merging of the upper and lower surface boundary layers. An iteration provides refinement of the potential flow induced pressure coupling to the viscous flow solutions. The final phase is a complete two dimensional Navier-Stokes analysis of the wake flow in the vicinity of a blunt-bases airfoil. A finite element numerical algorithm is presented which is applicable to solution of all partial differential equation sets of inviscid-viscous aerodynamic interaction algorithm. Numerical results are discussed.
Sharma, Gangavaram V M; Babu, Bommagani Shoban; Chatterjee, Deepak; Ramakrishna, Kallaganti V S; Kunwar, Ajit C; Schramm, Peter; Hofmann, Hans-Jörg
2009-09-04
An (S)-C-linked carbo-epsilon-amino acid [(S)-epsilon-Caa((x))] was prepared from the known (S)-delta-Caa. This monomer was utilized together with l-Ala to give novel alpha/epsilon-hybrid peptides in 1:1 alternation. Conformational analysis on penta- and hexapeptides by NMR (in CDCl(3)), CD, and MD studies led to the identification of robust 14/12-mixed helices. This is in agreement with the data from a theoretical conformational analysis on the basis of ab initio MO theory providing a complete overview on all formally possible hydrogen-bonded helix patterns of alpha/epsilon-hybrid peptides with 1:1 backbone alternation. The "new motif" of a mixed 14/12-helix was predicted as most stable in vacuum. Obviously, the formation of ordered secondary structures is also possible in peptide foldamers with amino acid constituents of considerable backbone lengths. Thus, alpha/epsilon-hybrid peptides expand the domain of foldamers and allow the introduction of desired functionalities via the alpha-amino acid constituents.
Optimal design of an activated sludge plant: theoretical analysis
NASA Astrophysics Data System (ADS)
Islam, M. A.; Amin, M. S. A.; Hoinkis, J.
2013-06-01
The design procedure of an activated sludge plant consisting of an activated sludge reactor and settling tank has been theoretically analyzed assuming that (1) the Monod equation completely describes the growth kinetics of microorganisms causing the degradation of biodegradable pollutants and (2) the settling characteristics are fully described by a power law. For a given reactor height, the design parameter of the reactor (reactor volume) is reduced to the reactor area. Then the sum total area of the reactor and the settling tank is expressed as a function of activated sludge concentration X and the recycled ratio α. A procedure has been developed to calculate X opt, for which the total required area of the plant is minimum for given microbiological system and recycled ratio. Mathematical relations have been derived to calculate the α-range in which X opt meets the requirements of F/ M ratio. Results of the analysis have been illustrated for varying X and α. Mathematical formulae have been proposed to recalculate the recycled ratio in the events, when the influent parameters differ from those assumed in the design.
Frimpong, Joseph Asamoah; Amo-Addae, Maame Pokuah; Adewuyi, Peter Adebayo; Hall, Casey Daniel; Park, Meeyoung Mattie; Nagbe, Thomas Knue
2017-01-01
Public health officials depend on timely, complete, and accurate surveillance data for decision making. The quality of data generated from surveillance is highly dependent on external and internal factors which may either impede or enhance surveillance activities. One way of identifying challenges affecting the quality of data generated is to conduct a data quality audit. This case study, based on an audit conducted by residents of the Liberia Frontline Field Epidemiology Training Program, was designed to be a classroom simulation of a data quality audit in a health facility. It is suited to enforce theoretical lectures in surveillance data quality and auditing. The target group is public health trainees, who should be able to complete this exercise in approximately 2 hours and 30 minutes.
The Far Infrared Vibration-Rotation Spectrum of the Ammonia Dimer.
NASA Astrophysics Data System (ADS)
Loeser, Jennifer Gertrud
1995-11-01
The ammonia dimer has been shown to exhibit unusual weak bonding properties relative to those of the other prototypical second row systems, the hydrogen fluoride dimer and the water dimer. The ultimate goal of the work initiated in this dissertation is to determine a complete intermolecular potential energy surface for the ammonia dimer. It is first necessary to observe its far infrared vibration-rotation-tunneling (VRT) spectrum and to develop a group theoretical model that explains this spectrum in terms of the internal dynamics of the ammonia dimer. These first steps are the subject of this dissertation. First, the current understanding of the ammonia dimer system is reviewed. Group theoretical descriptions of the nature of the ammonia dimer VRT states are explained in detail. An overview of the experimental and theoretical studies of the ammonia dimer made during the last decade is presented. Second, progress on the analysis of the microwave and far infrared spectrum of (ND_3)_2 below 13 cm^{-1} is reported. These spectra directly measure the 'donor -acceptor' interchange splittings in (ND_3) _2, and determine some of the monomer umbrella inversion tunneling splittings. Third, new 80-90 cm^{-1} far infrared spectra of (NH_3)_2 are presented and a preliminary analysis is proposed. Most of the new excited VRT states have been assigned as tunneling sublevels of an out-of-plane intermolecular vibration.
NASA Astrophysics Data System (ADS)
Al-Wahaibi, Lamya H.; Sujay, Subramaniam; Muthu, Gangadharan Ganesh; El-Emam, Ali A.; Venkataramanan, Natarajan S.; Al-Omary, Fatmah A. M.; Ghabbour, Hazem A.; Percino, Judith; Thamotharan, Subbiah
2018-05-01
A detailed structural analysis of two adamantane derivatives namely, ethyl 2-[(Z)-1-(adamantan-1-yl)-3-(phenyl)isothioureido]acetate I and ethyl 2-[(Z)-1-(adamantan-1-yl)-3-(4-fluorophenyl)isothioureido]acetate II is carried out to understand the effect of fluorine substitution. The introduction of fluorine atom alters the crystal packing and is completely different from its parent compound. The fluorine substitution drastically reduced the intermolecular H⋯H contacts and this reduction is compensated by intermolecular F⋯H and F⋯F contacts. The relative contributions of various intermolecular contacts present in these structures were quantified using Hirshfeld surface analysis. Energetically significant molecular pairs were identified from the crystal structures of these compounds using PIXEL method. The structures of I and II are optimized in gas and solvent phases using the B3LYP-D3/6-311++G(d,p) level of theory. The quantum theory of atoms-in-molecules (QTAIM) analysis was carried out to estimate the strengths of various intermolecular contacts present in these molecular dimers. The results suggest that the Hsbnd H bonding take part in the stabilization of crystal structures. The experimental and theoretical UV-Vis results show the variations in HOMO and LUMO energy levels. In silico docking analysis indicates that both compounds I and II may exhibit inhibitory activity against 11-β-hydroxysteroid dehydrogenase 1 (11-β-HSD1).
Theoretical Investigations of Clouds and Aerosols in the Stratosphere and Upper Troposphere
NASA Technical Reports Server (NTRS)
Toon, Owen B.
2005-01-01
support of the Atmospheric Chemistry Modeling and Data Analysis Program. We investigated a wide variety of issues involving ambient stratospheric aerosols, polar stratospheric clouds or heterogeneous chemistry, analysis of laboratory data, and particles in the upper troposphere. The papers resulting from these studies are listed below. In addition, I participated in the 1999-2000 SOLVE mission as one of the project scientists and in the 2002 CRYSTAL field mission as one of the project scientists. Several CU graduate students and research associates also participated in these mission, under support from the ACMAP program, and worked to interpret data. During the past few years my group has completed a number of projects under the
A simple white noise analysis of neuronal light responses.
Chichilnisky, E J
2001-05-01
A white noise technique is presented for estimating the response properties of spiking visual system neurons. The technique is simple, robust, efficient and well suited to simultaneous recordings from multiple neurons. It provides a complete and easily interpretable model of light responses even for neurons that display a common form of response nonlinearity that precludes classical linear systems analysis. A theoretical justification of the technique is presented that relies only on elementary linear algebra and statistics. Implementation is described with examples. The technique and the underlying model of neural responses are validated using recordings from retinal ganglion cells, and in principle are applicable to other neurons. Advantages and disadvantages of the technique relative to classical approaches are discussed.
Cumulative reports and publications
NASA Technical Reports Server (NTRS)
1993-01-01
A complete list of Institute for Computer Applications in Science and Engineering (ICASE) reports are listed. Since ICASE reports are intended to be preprints of articles that will appear in journals or conference proceedings, the published reference is included when it is available. The major categories of the current ICASE research program are: applied and numerical mathematics, including numerical analysis and algorithm development; theoretical and computational research in fluid mechanics in selected areas of interest to LaRC, including acoustics and combustion; experimental research in transition and turbulence and aerodynamics involving LaRC facilities and scientists; and computer science.
Hentz, A; Parkinson, G S; Quinn, P D; Muñoz-Márquez, M A; Woodruff, D P; Grande, P L; Schiwietz, G; Bailey, P; Noakes, T C Q
2009-03-06
The energy spectrum associated with scattering of 100 keV H+ ions from the outermost few atomic layers of Cu(111) in different scattering geometries provides direct evidence of trajectory-dependent electronic energy loss. Theoretical simulations, combining standard Monte Carlo calculations of the elastic scattering trajectories with coupled-channel calculations to describe inner-shell ionization and excitation as a function of impact parameter, reproduce the effects well and provide a means for far more complete analysis of medium-energy ion scattering data.
Sathiyaraj, T; Balasubramaniam, P
2017-11-30
This paper presents a new set of sufficient conditions for controllability of fractional higher order stochastic integrodifferential systems with fractional Brownian motion (fBm) in finite dimensional space using fractional calculus, fixed point technique and stochastic analysis approach. In particular, we discuss the complete controllability for nonlinear fractional stochastic integrodifferential systems under the proved result of the corresponding linear fractional system is controllable. Finally, an example is presented to illustrate the efficiency of the obtained theoretical results. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.
Distributed sensor networks: a cellular nonlinear network perspective.
Haenggi, Martin
2003-12-01
Large-scale networks of integrated wireless sensors become increasingly tractable. Advances in hardware technology and engineering design have led to dramatic reductions in size, power consumption, and cost for digital circuitry, and wireless communications. Networking, self-organization, and distributed operation are crucial ingredients to harness the sensing, computing, and computational capabilities of the nodes into a complete system. This article shows that those networks can be considered as cellular nonlinear networks (CNNs), and that their analysis and design may greatly benefit from the rich theoretical results available for CNNs.
NASA Astrophysics Data System (ADS)
Paiva, F. M.; Batista, J. C.; Rêgo, F. S. C.; Lima, J. A.; Freire, P. T. C.; Melo, F. E. A.; Mendes Filho, J.; de Menezes, A. S.; Nogueira, C. E. S.
2017-01-01
Single crystals of DL-valine and DL-lysine hydrochloride were grown by slow evaporation method and the crystallographic structure were confirmed by X-ray diffraction experiment and Rietveld method. These two crystals have been studied by Raman spectroscopy in the 25-3600 cm-1 spectral range and by infrared spectroscopy through the interval 375-4000 cm-1 at room temperature. Experimental and theoretical vibrational spectra were compared and a complete analysis of the modes was done in terms of the Potential Energy Distribution (PED).
Lim, Kwang Soo; Baldoví, José J; Jiang, ShangDa; Koo, Bong Ho; Kang, Dong Won; Lee, Woo Ram; Koh, Eui Kwan; Gaita-Ariño, Alejandro; Coronado, Eugenio; Slota, Michael; Bogani, Lapo; Hong, Chang Seop
2017-05-01
Controlling the coordination sphere of lanthanoid complexes is a challenging critical step toward controlling their relaxation properties. Here we present the synthesis of hexacoordinated dysprosium single-molecule magnets, where tripodal ligands achieve a near-perfect octahedral coordination. We perform a complete experimental and theoretical investigation of their magnetic properties, including a full single-crystal magnetic anisotropy analysis. The combination of electrostatic and crystal-field computational tools (SIMPRE and CONDON codes) allows us to explain the static behavior of these systems in detail.
NASA Astrophysics Data System (ADS)
Ferber, Steven Dwight
2005-11-01
The Vibrational Circular Dichroism (VCD) of Nucleic Acids is a sensitive function of their conformation. DeVoe's classically derived polarizability theory allows the calculation of polymer absorption and circular dichroism spectra in any frequency range. Following the approach of Tinoco and Cech as modified by Moore and Self, calculations were done in the infrared (IR) region with theoretically derived monomer input parameters. Presented herein are calculated absorption and CD spectra for nucleic acid oligomers and polymers. These calculations improve upon earlier attempts, which utilized frequencies, intensities and normal modes from empirical analysis of the nitrogenous base of the monomers. These more complete input polarizability parameters include all contributions to specific vibrational normal modes for the entire nucleotide structure. They are derived from density functional theory (DFT) vibrational analysis on quasi-nucleotide monomers using the GAUSSIAN '98/'03 program. The normal modes are "integrated" for the first time into single virtual (DeVoe) oscillators by incorporating "fixed partial charges" in the manner of Schellman. The results include the complete set of monomer normal modes. All of these modes may be analyzed, in a manner similar to those demonstrated here (for the 1500-1800 cm-1 region). A model is utilized for the polymer/oligomer monomers which maintains the actual electrostatic charge on the adjacent protonated phosphoryl groups (hydrogen phosphate, a mono-anion). This deters the optimization from "collapsing" into a hydrogen-bonded "ball" and thereby maintains the extended (polymer-like) conformation. As well, the precise C2 "endo" conformation of the sugar ring is maintained in the DNA monomers. The analogous C3 "endo" conformation is also maintained for the RNA monomers, which are constrained by massive "anchors" at the phosphates. The complete IR absorbance spectra (0-4,000 cm-1) are calculated directly in Gaussian. Calculated VCD and Absorbance Spectra for the eight standard Ribonucleic and Deoxy-ribonucleic acid homo-polymers in the nitrogenous base absorbing region 1550-1750 cm-1 are presented. These spectra match measured spectra at least as well as spectra calculated from empirical parameters. These results demonstrate that the purely theoretical calculation, an example given herein, should serve to provide more transferable, universal parameters for the polarizability treatment of the optical properties of oligomers and polymers.
NASA Astrophysics Data System (ADS)
González-Montiel, Simplicio; Valdez-Calderón, Alejandro; Vásquez-Pérez, J. Manuel; Torres-Valencia, J. Martín; Martínez-Otero, Diego; López, Jorge A.; Cruz-Borbolla, Julián
2017-10-01
A new series of chrysin derivatives containing the di-(2-picolyl)amine (2a-d) moiety have been designed, synthesized, and treated with PdCl2·2CH3CN allowing the preparation of new cationic Palladium(II) complexes (3a-d). Solution-phase studies by 1H NMR spectroscopy of 3a-d revealed that the protons of the methylene groups of the di(2-picolyl)amine fragment are diasterotopic. GIAO/DFT studies were performed to predict the molecular structures of 3a-d by comparing the experimental and theoretical 1H-NMR chemical shifts. The molecular structure of 3c was determined by X-ray crystallographic analysis revealing that di-(2-picolyl)amine fragment is coordinated to the palladium center in a κ3-N,N,N-tridentate fashion in an overall square-planar geometry completed with a chloride atom.
Communication: Electron ionization of DNA bases
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rahman, M. A.; Krishnakumar, E., E-mail: ekkumar@tifr.res.in
2016-04-28
No reliable experimental data exist for the partial and total electron ionization cross sections for DNA bases, which are very crucial for modeling radiation damage in genetic material of living cell. We have measured a complete set of absolute partial electron ionization cross sections up to 500 eV for DNA bases for the first time by using the relative flow technique. These partial cross sections are summed to obtain total ion cross sections for all the four bases and are compared with the existing theoretical calculations and the only set of measured absolute cross sections. Our measurements clearly resolve themore » existing discrepancy between the theoretical and experimental results, thereby providing for the first time reliable numbers for partial and total ion cross sections for these molecules. The results on fragmentation analysis of adenine supports the theory of its formation in space.« less
Nikolaev, V P
2008-01-01
Theoretical analysis of the risk of decompression illness (DI) during extravehicular activity following the Russian and NASA decompression protocols (D-R and D-US, respectively) was performed. In contrast to the tradition approach to decompression stress evaluation by the factor of tissue supersaturation with nitrogen, our probabilistic theory of decompression safety provides a completely reasoned evaluation and comparison of the levels of hazard of these decompression protocols. According to this theory, the function of cumulative DI risk is equal to the sum of functions of cumulative risk of lesion of all body tissues by gas bubbles and their supersaturation by solute gases. Based on modeling of dynamics of these functions, growth of the DI cumulative risk in the course of D-R and D-US follows essentially similar trajectories within the time-frame of up to 330 minutes. However, further extension of D-US but not D-R raises the risk of DI drastically.
Child Language Acquisition: Contrasting Theoretical Approaches
ERIC Educational Resources Information Center
Ambridge, Ben; Lieven, Elena V. M.
2011-01-01
Is children's language acquisition based on innate linguistic structures or built from cognitive and communicative skills? This book summarises the major theoretical debates in all of the core domains of child language acquisition research (phonology, word-learning, inflectional morphology, syntax and binding) and includes a complete introduction…
NASA Astrophysics Data System (ADS)
Pickett, Derek Kyle
Due to an increased interest in sustainable energy, biodiesel has become much more widely used in the last several years. Glycerin, one major waste component in biodiesel production, can be converted into a hydrogen rich synthesis gas to be used in an engine generator to recover energy from the biodiesel production process. This thesis contains information detailing the production, testing, and analysis of a unique synthesis generator rig at the University of Kansas. Chapter 2 gives a complete background of all major components, as well as how they are operated. In addition to component descriptions, methods for operating the system on pure propane, reformed propane, reformed glycerin along with the methodology of data acquisition is described. This chapter will serve as a complete operating manual for future students to continue research on the project. Chapter 3 details the literature review that was completed to better understand fuel reforming of propane and glycerin. This chapter also describes the numerical model produced to estimate the species produced during reformation activities. The model was applied to propane reformation in a proof of concept and calibration test before moving to glycerin reformation and its subsequent combustion. Chapter 4 first describes the efforts to apply the numerical model to glycerin using the calibration tools from propane reformation. It then discusses catalytic material preparation and glycerin reformation tests. Gas chromatography analysis of the reformer effluent was completed to compare to theoretical values from the numerical model. Finally, combustion of reformed glycerin was completed for power generation. Tests were completed to compare emissions from syngas combustion and propane combustion.
A new analysis of the unwinding ribbon as a delayed arming device
NASA Astrophysics Data System (ADS)
Dunn, W. P.
1982-06-01
The objective of this work was to formulate theoretical methods to enable engineers to design unwinding ribbons for use as delay arming mechanisms with reasonable accuracy and a minimum development effort. The unwinding ribbon considered here is a "wrapped' spring, which is a spiral spring made from flat metal stock closely wound. In the unstressed condition all the coils of the spring are touching. The results of the analysis are given and compared with the experimental results obtained by T. B. Alfriend. This is a more complete study than that of Alfriend since no assumptions are made concerning the moment of inertia of the coil and hub or the tension force in the ribbon bridge. Hence, two empirical constants in Alfriend's analysis were dropped in favor of exact expressions.
Bagstad, Kenneth J.; Villa, Ferdinando; Batker, David; Harrison-Cox, Jennifer; Voigt, Brian; Johnson, Gary W.
2014-01-01
Ecosystem services mapping and modeling has focused more on supply than demand, until recently. Whereas the potential provision of economic benefits from ecosystems to people is often quantified through ecological production functions, the use of and demand for ecosystem services has received less attention, as have the spatial flows of services from ecosystems to people. However, new modeling approaches that map and quantify service-specific sources (ecosystem capacity to provide a service), sinks (biophysical or anthropogenic features that deplete or alter service flows), users (user locations and level of demand), and spatial flows can provide a more complete understanding of ecosystem services. Through a case study in Puget Sound, Washington State, USA, we quantify and differentiate between the theoretical or in situ provision of services, i.e., ecosystems’ capacity to supply services, and their actual provision when accounting for the location of beneficiaries and the spatial connections that mediate service flows between people and ecosystems. Our analysis includes five ecosystem services: carbon sequestration and storage, riverine flood regulation, sediment regulation for reservoirs, open space proximity, and scenic viewsheds. Each ecosystem service is characterized by different beneficiary groups and means of service flow. Using the ARtificial Intelligence for Ecosystem Services (ARIES) methodology we map service supply, demand, and flow, extending on simpler approaches used by past studies to map service provision and use. With the exception of the carbon sequestration service, regions that actually provided services to people, i.e., connected to beneficiaries via flow paths, amounted to 16-66% of those theoretically capable of supplying services, i.e., all ecosystems across the landscape. These results offer a more complete understanding of the spatial dynamics of ecosystem services and their effects, and may provide a sounder basis for economic valuation and policy applications than studies that consider only theoretical service provision and/or use.
Pessoa, L; Thompson, E; Noë, A
1998-12-01
In visual science the term filling-in is used in different ways, which often leads to confusion. This target article presents a taxonomy of perceptual completion phenomena to organize and clarify theoretical and empirical discussion. Examples of boundary completion (illusory contours) and featural completion (color, brightness, motion, texture, and depth) are examined, and single-cell studies relevant to filling-in are reviewed and assessed. Filling-in issues must be understood in relation to theoretical issues about neural-perceptual isomorphism and linking propositions. Six main conclusions are drawn: (1) visual filling-in comprises a multitude of different perceptual completion phenomena; (2) certain forms of visual completion seem to involve spatially propagating neural activity (neural filling-in) and so, contrary to Dennett's (1991; 1992) recent discussion of filling-in, cannot be described as results of the brain's "ignoring an absence" or "jumping to a conclusion"; (3) in certain cases perceptual completion seems to have measurable effects that depend on neural signals representing a presence rather than ignoring an absence; (4) neural filling-in does not imply either "analytic isomorphism" or "Cartesian materialism," and thus the notion of the bridge locus--a particular neural stage that forms the immediate substrate of perceptual experience--is problematic and should be abandoned; (5) to reject the representational conception of vision in favor of an "enactive" or "animate" conception reduces the importance of filling-in as a theoretical category in the explanation of vision; and (6) the evaluation of perceptual content should not be determined by "subpersonal" considerations about internal processing, but rather by considerations about the task of vision at the level of the animal or person interacting with the world.
Design, engineering and evaluation of refractory liners for slagging gasifiers. Final report
DOE Office of Scientific and Technical Information (OSTI.GOV)
deTineo, B J; Booth, G; Firestone, R F
1982-08-01
The contract for this program was awarded at the end of September 1978. Work was started on 1 October 1978, on Tasks A, B, and E. Task A, Conceptual Liner Designs, and Task B, Test System Design and Construction, were completed. Task C, Liner Tests, and Task D, Liner Design Evaluation, were to begin upon completion of Task B. Task E, Liner Model Development, is inactive after an initial data compilation and theoretical model development effort. It was to be activated as soon as data were available from Task D. Task F, Liner Design Handbook, was active along with Taskmore » A since the reports of both tasks were to use the same format. At this time, Tasks C, D, and F are not to be completed since funding of this project was phased out by DOE directive. The refractory text facility, which was constructed, was tested and found to perform satisfactorily. It is described in detail, including a hazard analysis which was performed. (LTN)« less
Vibrational, UV spectra, NBO, first order hyperpolarizability and HOMO-LUMO analysis of carvedilol
NASA Astrophysics Data System (ADS)
Swarnalatha, N.; Gunasekaran, S.; Nagarajan, M.; Srinivasan, S.; Sankari, G.; Ramkumaar, G. R.
2015-02-01
In this work, we have investigated experimentally and theoretically on the molecular structure, vibrational spectra, UV spectral analysis and NBO studies of cardio-protective drug carvedilol. The FT-Raman and FT-IR spectra for carvedilol in the solid phase have been recorded in the region 4000-100 cm-1 and 4000-400 cm-1 respectively. Theoretical calculations were performed by using density functional theory (DFT) method at B3LYP/6-31G(d,p) and B3LYP/6-31++G(d,p) basis set levels. The harmonic vibrational frequencies, the optimized geometric parameters have been interpreted and compared with the reported experimental values. The complete vibrational assignments were performed on the basis of potential energy distribution (PED) of the vibrational modes. The thermodynamic properties and molecular electrostatic potential surfaces of the molecule were constructed. The electronic absorption spectrum was recorded in the region 400-200 nm and electronic properties such as HOMO and LUMO energies were calculated. The stability of the molecule arising from hyper conjugative interactions and charge delocalization have been analyzed from natural bond orbital (NBO) analysis. The first order hyperpolarizability of the title molecule was also calculated. The photo stability of carvedilol under different storage conditions were analyzed using UV-Vis spectral technique.
Applying a contemporary grounded theory methodology.
Licqurish, Sharon; Seibold, Carmel
2011-01-01
The aim of this paper is to discuss the application of a contemporary grounded theory methodology to a research project exploring the experiences of students studying for a degree in midwifery. Grounded theory is a qualitative research approach developed by Glaser and Strauss in the 1950s but the methodology for this study was modelled on Clarke's (2005) approach and was underpinned by a symbolic interactionist theoretical perspective, post-structuralist theories of Michel Foucault and a constructionist epistemology. The study participants were 19 midwifery students completing their final placement. Data were collected through individual in-depth interviews and participant observation, and analysed using the grounded theory analysis techniques of coding, constant comparative analysis and theoretical sampling, as well as situational maps. The analysis focused on social action and interaction and the operation of power in the students' environment. The social process in which the students were involved, as well as the actors and discourses that affected the students' competency development, were highlighted. The methodology allowed a thorough exploration of the students' experiences of achieving competency. However, some difficulties were encountered. One of the major issues related to the understanding and application of complex sociological theories that challenged positivist notions of truth and power. Furthermore, the mapping processes were complex. Despite these minor challenges, the authors recommend applying this methodology to other similar research projects.
NASA Astrophysics Data System (ADS)
Fitzpatrick, Richard
2017-12-01
'Theoretical Fluid Mechanics' has been written to aid physics students who wish to pursue a course of self-study in fluid mechanics. It is a comprehensive, completely self-contained text with equations of fluid mechanics derived from first principles, and any required advanced mathematics is either fully explained in the text, or in an appendix. It is accompanied by about 180 exercises with completely worked out solutions. It also includes extensive sections on the application of fluid mechanics to topics of importance in astrophysics and geophysics. These topics include the equilibrium of rotating, self-gravitating, fluid masses; tidal bores; terrestrial ocean tides; and the Eddington solar model.
Low temperature deformation behavior of an electromagnetically bulged 5052 aluminum alloy
Li, Zu; Li, Ning; Wang, Duzhen; Ouyang, Di; Liu, Lin
2016-01-01
The fundamental understanding of the deformation behavior of electromagnetically formed metallic components under extreme conditions is important. Here, the effect of low temperature on the deformation behavior of an electromagnetically-bulged 5052 aluminum alloy was investigated through uniaxial tension. We found that the Portevin-Le Chatelier Effect, designated by the serrated characteristic in stress-strain curves, continuously decays until completely disappears with decreasing temperature. The physical origin of the phenomenon is rationalized on the basis of the theoretical analysis and the Monte Carlo simulation, which reveal an increasing resistance to dislocation motion imposed by lowering temperature. The dislocations are captured completely by solute atoms at −50 °C, which results in the extinction of Portevin-Le Chatelier. The detailed mechanism responsible for this process is further examined through Monte Carlo simulation. PMID:27426919
Gasulla, Ivana; Sancho, Juan; Capmany, José; Lloret, Juan; Sales, Salvador
2010-12-06
We theoretically and experimentally evaluate the propagation, generation and amplification of signal, harmonic and intermodulation distortion terms inside a Semiconductor Optical Amplifier (SOA) under Coherent Population Oscillation (CPO) regime. For that purpose, we present a general optical field model, valid for any arbitrarily-spaced radiofrequency tones, which is necessary to correctly describe the operation of CPO based slow light Microwave Photonic phase shifters which comprise an electrooptic modulator and a SOA followed by an optical filter and supplements another recently published for true time delay operation based on the propagation of optical intensities. The phase shifter performance has been evaluated in terms of the nonlinear distortion up to 3rd order, for a modulating signal constituted of two tones, in function of the electrooptic modulator input RF power and the SOA input optical power, obtaining a very good agreement between theoretical and experimental results. A complete theoretical spectral analysis is also presented which shows that under small signal operation conditions, the 3rd order intermodulation products at 2Ω1 + Ω2 and 2Ω2 + Ω1 experience a power dip/phase transition characteristic of the fundamental tones phase shifting operation.
NASA Astrophysics Data System (ADS)
Silvia, Devin
2015-10-01
Understanding the complex nature of the circumgalactic medium (CGM) has been a target of numerous research efforts, both observationally and theoretically. While significant progress has been made in probing the structure and thermodynamic state of the CGM through the detection of metal line absorption systems using the Hubble Space Telescope (HST), a complete picture of the physical mechanisms that produce the observed properties does not yet exist. Recent theoretical work has suggested that a delicate balance between radiative cooling and thermal feedback detemines whether or not the CGM is capable of sustaining a stable, multiphase medium that would allow cool clouds to precipitate out of the galactic halo. This new theoretical framework may provide the explanation for many observational results. In this project, we will detemine whether or not this elegant and simple precipitation model can be supported by physics-rich numerical simulations of isolated galaxies. We will use our simulations to gain a deeper understanding of the precipitation model and explore the ionization and temperature stucture of the CGM. Our analysis will include the comparison of realistic synthetic spectra to those produced by HST, using the newly-developed Trident software package.
Analysis of Implicit Uncertain Systems. Part 1: Theoretical Framework
1994-12-07
Analysis of Implicit Uncertain Systems Part I: Theoretical Framework Fernando Paganini * John Doyle 1 December 7, 1994 Abst rac t This paper...Analysis of Implicit Uncertain Systems Part I: Theoretical Framework 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S...model and a number of constraints relevant to the analysis problem under consideration. In Part I of this paper we propose a theoretical framework which
NASA Astrophysics Data System (ADS)
Giardina, G.; Nasirov, A. K.; Mandaglio, G.; Curciarello, F.; De Leo, V.; Fazio, G.; Manganaro, M.; Romaniuk, M.; Saccá, C.
2011-02-01
The hindrance to complete fusion is a phenomenon presenting in the most part of the capture events in reactions with massive nuclei. This phenomenon is due to the onset of the quasifission process which competes with complete fusion during the evolution of the composed system formed at capture stage. The branching ratio between quasifission and complete fusion strongly depends from different characteristics of reacting nuclei in the entrance channel. The experimental and theoretical investigations of reaction dynamics connected with the formation of composed system is nowadays the main subject of the nuclear reactions. There is ambiguity in establishment of the reaction mechanism leading to the observed binary fissionlike fragments. The correct estimation of the fusion probability is important in planning experiments for the synthesis of superheavy elements. The experimental determination of evaporation residues only is not enough to restore the true reaction dynamics. The experimental observation of fissionlike fragments only cannot assure the correct distinguishing of products of the quasifission, fast fission, and fusion-fission processes which have overlapping in the mass (angular, kinetic energy) distributions of fragments. In this paper we consider a wide set of reactions (with different mass asymmetry and mass symmetry parameters) with the aim to explain the role played by many quantities on the reaction mechanisms. We also present the results of study of the 48Ca+249Bk reaction used to synthesize superheavy nuclei with Z = 117 by the determination of the evaporation residue cross sections and the effective fission barriers < Bf > of excited nuclei formed along the de-excitation cascade of the compound nucleus.
Compassion satisfaction: A concept analysis in nursing.
Sacco, Tara L; Copel, Linda Carman
2018-01-01
Nurses experience an intrinsic sense of fulfillment derived from their work in caring for other people. There is a need to further investigate the concept of compassion satisfaction as it is experienced in the profession of nursing. The aim of this analysis is to provide clarity to the concept of compassion satisfaction in nursing. A search of social work and nursing literature was completed. The search terms "compassion satisfaction," "nursing," "social workers," "teachers," and "educators" were entered in various combinations to the CINAHL, Journals@Ovid, ProQuest Nursing & Allied Health Source, ProQuest Psychology Journals, PsychINFO, ERIC, and Education Full Text databases. A comprehensive review of the literature was completed to identify features of compassion satisfaction. Utilizing the Walker and Avant method, assumptions, antecedents, characteristics, and consequences of compassion satisfaction were identified. A conceptual model of compassion satisfaction was developed encompassing 7 antecedents, 11 characteristics, and 8 consequences. Further, a theoretical definition of compassion satisfaction in nursing was derived. There is a need to focus on the positive effects of caring. This concept analysis provides the initial step to strengthening the science related to compassion satisfaction in nursing and other helping professions. © 2017 Wiley Periodicals, Inc.
A Study on the Security Levels of Spread-Spectrum Embedding Schemes in the WOA Framework.
Wang, Yuan-Gen; Zhu, Guopu; Kwong, Sam; Shi, Yun-Qing
2017-08-23
Security analysis is a very important issue for digital watermarking. Several years ago, according to Kerckhoffs' principle, the famous four security levels, namely insecurity, key security, subspace security, and stego-security, were defined for spread-spectrum (SS) embedding schemes in the framework of watermarked-only attack. However, up to now there has been little application of the definition of these security levels to the theoretical analysis of the security of SS embedding schemes, due to the difficulty of the theoretical analysis. In this paper, based on the security definition, we present a theoretical analysis to evaluate the security levels of five typical SS embedding schemes, which are the classical SS, the improved SS (ISS), the circular extension of ISS, the nonrobust and robust natural watermarking, respectively. The theoretical analysis of these typical SS schemes are successfully performed by taking advantage of the convolution of probability distributions to derive the probabilistic models of watermarked signals. Moreover, simulations are conducted to illustrate and validate our theoretical analysis. We believe that the theoretical and practical analysis presented in this paper can bridge the gap between the definition of the four security levels and its application to the theoretical analysis of SS embedding schemes.
A Taylor weak-statement algorithm for hyperbolic conservation laws
NASA Technical Reports Server (NTRS)
Baker, A. J.; Kim, J. W.
1987-01-01
Finite element analysis, applied to computational fluid dynamics (CFD) problem classes, presents a formal procedure for establishing the ingredients of a discrete approximation numerical solution algorithm. A classical Galerkin weak-statement formulation, formed on a Taylor series extension of the conservation law system, is developed herein that embeds a set of parameters eligible for constraint according to specification of suitable norms. The derived family of Taylor weak statements is shown to contain, as special cases, over one dozen independently derived CFD algorithms published over the past several decades for the high speed flow problem class. A theoretical analysis is completed that facilitates direct qualitative comparisons. Numerical results for definitive linear and nonlinear test problems permit direct quantitative performance comparisons.
Computational Control of Flexible Aerospace Systems
NASA Technical Reports Server (NTRS)
Sharpe, Lonnie, Jr.; Shen, Ji Yao
1994-01-01
The main objective of this project is to establish a distributed parameter modeling technique for structural analysis, parameter estimation, vibration suppression and control synthesis of large flexible aerospace structures. This report concentrates on the research outputs produced in the last two years of the project. The main accomplishments can be summarized as follows. A new version of the PDEMOD Code had been completed. A theoretical investigation of the NASA MSFC two-dimensional ground-based manipulator facility by using distributed parameter modelling technique has been conducted. A new mathematical treatment for dynamic analysis and control of large flexible manipulator systems has been conceived, which may provide a embryonic form of a more sophisticated mathematical model for future modified versions of the PDEMOD Codes.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Shestermanov, K.E.; Vasiliev, A.N; /Serpukhov, IHEP
2005-12-01
A precise measurement of the angle {alpha} in the CKM triangle is very important for a complete test of Standard Model. A theoretically clean method to extract {alpha} is provided by B{sup 0} {yields} {rho}{pi} decays. Monte Carlo simulations to obtain the BTeV reconstruction efficiency and to estimate the signal to background ratio for these decays were performed. Finally the time-dependent Dalitz plot analysis, using the isospin amplitude formalism for tre and penguin contributions, was carried out. It was shown that in one year of data taking BTeV could achieve an accuracy on {alpha} better than 5{sup o}.
Coherent population transfer in multilevel systems with magnetic sublevels. II. Algebraic analysis
NASA Astrophysics Data System (ADS)
Martin, J.; Shore, B. W.; Bergmann, K.
1995-07-01
We extend previous theoretical work on coherent population transfer by stimulated Raman adiabatic passage for states involving nonzero angular momentum. The pump and Stokes fields are either copropagating or counterpropagating with the corresponding linearly polarized electric-field vectors lying in a common plane with the magnetic-field direction. Zeeman splitting lifts the magnetic sublevel degeneracy. We present an algebraic analysis of dressed-state properties to explain the behavior noted in numerical studies. In particular, we discuss conditions which are likely to lead to a failure of complete population transfer. The applied strategy, based on simple methods of linear algebra, will also be successful for other types of discrete multilevel systems, provided the rotating-wave and adiabatic approximation are valid.
Generalized theory for seaplane impact
NASA Technical Reports Server (NTRS)
Milwitzky, Benjamin
1952-01-01
The motions, hydrodynamic loads, and pitching moments experienced by v-bottom seaplanes during step-landing impacts are analyzed and the theoretical results are compared with experimental data. In the analysis, the primary flow about the immersed portion of a keeled hull or float is considered to occur in transverse flow planes and the concept of virtual mass is applied to determined the reaction of the water to the motions of the seaplane. The entire immersion process is analyzed from the instant of initial contact until the seaplane rebounds from the water surfaces. The analysis is applicable to the complete range of initial contact conditions between the case of impacts where the resultant velocity is normal to the keel and the limiting condition of planing.
Complete wetting of graphene by biological lipids
NASA Astrophysics Data System (ADS)
Luan, Binquan; Huynh, Tien; Zhou, Ruhong
2016-03-01
Graphene nanosheets have been demonstrated to extract large amounts of lipid molecules directly out of the cell membrane of bacteria and thus cause serious damage to the cell's integrity. This interesting phenomenon, however, is so far not well understood theoretically. Here through extensive molecular dynamics simulations and theoretical analyses, we show that this phenomenon can be categorized as a complete wetting of graphene by membrane lipids in water. A wetting-based theory was utilized to associate the free energy change during the microscopic extraction of a lipid with the spreading parameter for the macroscopic wetting. With a customized thermodynamic cycle for detailed energetics, we show that the dispersive adhesion between graphene and lipids plays a dominant role during this extraction as manifested by the curved graphene. Our simulation results suggest that biological lipids can completely wet the concave, flat or even convex (with a small curvature) surface of a graphene sheet.Graphene nanosheets have been demonstrated to extract large amounts of lipid molecules directly out of the cell membrane of bacteria and thus cause serious damage to the cell's integrity. This interesting phenomenon, however, is so far not well understood theoretically. Here through extensive molecular dynamics simulations and theoretical analyses, we show that this phenomenon can be categorized as a complete wetting of graphene by membrane lipids in water. A wetting-based theory was utilized to associate the free energy change during the microscopic extraction of a lipid with the spreading parameter for the macroscopic wetting. With a customized thermodynamic cycle for detailed energetics, we show that the dispersive adhesion between graphene and lipids plays a dominant role during this extraction as manifested by the curved graphene. Our simulation results suggest that biological lipids can completely wet the concave, flat or even convex (with a small curvature) surface of a graphene sheet. Electronic supplementary information (ESI) available: The movie showing the simulation trajectory for the extraction of lipids from the membrane. See DOI: 10.1039/C6NR00202A
Nkenke, Emeka; Vairaktaris, Elefterios; Bauersachs, Anne; Eitner, Stephan; Budach, Alexander; Knipfer, Christoph; Stelzle, Florian
2012-03-30
Technology-enhanced learning (TEL) gives a view to improved education. However, there is a need to clarify how TEL can be used effectively. The study compared students' attitudes and opinions towards a traditional face-to-face course on theoretical radiological science and a TEL course where students could combine face-to-face lectures and e-learning modules at their best convenience. 42 third-year dental students were randomly assigned to the traditional face-to-face group and the TEL group. Both groups completed questionnaires before the beginning and after completion of the course on attitudes and opinions towards a traditional face-to-face lectures and technology-enhanced learning. After completion of the course both groups also filled in the validated German-language TRIL (Trierer Inventar zur Lehrevaluation) questionnaire for the evaluation of courses given at universities. Both groups had a positive attitude towards e-learning that did not change over time. The TEL group attended significantly less face-to-face lectures than the traditional group. However, both groups stated that face-to-face lectures were the basis for education in a theoretical radiological science course. The members of the TEL group rated e-mail reminders significantly more important when they filled in the questionnaire on attitudes and opinions towards a traditional face-to-face lectures and technology-enhanced learning for the second time after completion of the course. The members of the technology-enhanced learning group were significantly less confident in passing the exam compared to the members of the traditional group. However, examination results did not differ significantly for traditional and the TEL group. It seems that technology-enhanced learning in a theoretical radiological science course has the potential to reduce the need for face-to-face lectures. At the same time examination results are not impaired. However, technology-enhanced learning cannot completely replace traditional face-to-face lectures, because students indicate that they consider traditional teaching as the basis of their education.
NASA Astrophysics Data System (ADS)
Menon, Vidya V.; Foto, Egemen; Mary, Y. Sheena; Karatas, Esin; Panicker, C. Yohannan; Yalcin, Gözde; Armaković, Stevan; Armaković, Sanja J.; Van Alsenoy, C.; Yildiz, Ilkay
2017-02-01
FT-IR and FT-Raman spectra of 5-nitro-2-phenoxymethylbenzimidazole were recorded and analyzed theoretically and experimentally. The splitting of Nsbnd H stretching mode in the IR spectrum with a red shift from the calculated value indicates the weakening of the NH bond. The theoretical calculations give the phenyl ring breathing modes at 999 cm-1 for mono substituted benzene ring and at 1040 cm-1 for tri-substituted benzene ring. The theoretical NMR chemical shifts are in agreement with the experimental chemical shifts. The most reactive sites for electrophilic and nucleophilic attack are predicted from the MEP analysis. HOMO of π nature is delocalized over the entire molecule whereas the LUMO is located over the complete molecule except mono-substituted phenyl ring and oxygen atom. Reactive sites of the title molecule have been located with the help of ALIE surfaces and Fukui functions. In order to determine locations prone to autoxidation and locations interesting for starting of degradation, bond dissociation energies have been calculated for all single acyclic bonds. For the determination of atoms with pronounced interactions with water we have calculated radial distribution functions obtained after molecular dynamics simulations. The calculated first hyperpolarizability of the title compound is 58.03 times that of standard nonlinear optical material urea. The substrate binding site interactions of the title compound with Topo II enzyme is reported by using molecular docking study. Biological activity studies show that the title compound can be leaded for developing new anticancer agents.
NASA Astrophysics Data System (ADS)
Mıhçıokur, Özlem; Özpozan, Talat
2015-12-01
N-(3-chloro-4fluoro-phenyl)-7-methoxy-6-(3-morpholin-4ylpropoxy)-quinazolin-4-amine (GEF), a quinalizoline derivative used as new anti-cancer agent, designed to target activity of epidermal growth factor receptor (EGFR) promoting the growth, division and spread of cancer cells, was examined from the vibrational and theoretical point of view. All calculations have been carried out both in gaseous and aqueous phases. In the calculations of both phases, the molecule has been optimized through conformer analysis beginning with the x-ray data. The conformer analyses have been carried out in each phases and the geometrical differences between the most stable structures in gaseous and in aqueous phases have been discussed. The solvent effect for GEF in aqueous solution was simulated by using self-consistent reaction field (SCRF) calculations employing the integral equation formalism variant (IEFPCM) model. NBO analysis has been performed to indicate the presence of intramolecular charge transfer. The complete assignments of the vibrational spectra (IR&Raman) were made with the aid of calculated spectra both in gaseous and aqueous phases. The observed spectral data of the title compound were compared with the calculated spectra obtained by DFT/B3LYP and DFT/B3PW91 methods using 6-31G(d,p) basis set. The theoretical results were found to be in good agreement with the measured experimental data especially for the interpretation of intra molecular interactions.
Keegan, Conor; Conroy, Ronán; Doyle, Frank
2016-02-01
Depression is associated with increased mortality in patients with acute coronary syndrome (ACS). However, little is known about the theoretical causes of depression trajectories post-ACS, and whether these trajectories predict subsequent morbidity/mortality. We tested a longitudinal model of depressive vulnerabilities, trajectories and mortality. A prospective observational study of 374 ACS patients was conducted. Participants completed questionnaires on theoretical vulnerabilities (interpersonal life events, reinforcing events, cognitive distortions, and Type D personality) during hospitalisation and depression at baseline and 3, 6 and 12 months post-hospitalisation. Latent class analysis determined trajectories of depression. Path analysis was used to test relationships among vulnerabilities, depression trajectories and outcomes (combination of 1-year morbidity and 7-year mortality). Vulnerabilities independently predicted persistent and subthreshold depression trajectory categories, with effect sizes significantly highest for persistent depression. Both subthreshold and persistent depression trajectories were significant predictors of morbidity/mortality (e.g. persistent depression OR=2.4, 95% CI=1.8-3.1, relative to never depressed). Causality cannot be inferred from these associations. We had no measures of history of depression or treatments, which may affect associations. Theoretical vulnerabilities predicted depression trajectories, which in turn predicted increased morbidity/mortality, demonstrating for the first time a potential longitudinal chain of events post-ACS. This longitudinal model has important practical implications as clinicians can use vulnerability measures to identify those at most risk of poor outcomes. Copyright © 2015. Published by Elsevier B.V.
Theoretical Orientation and Personality of the Therapist: A Graduate Student Sample
ERIC Educational Resources Information Center
Ivanovic, Mirka
2011-01-01
The current study adds to the literature--and addresses several identified limitations--about the relationship between therapist trainees' personality traits and their preference for a particular theoretical orientation(s). Therapist trainees (N = 197) in a Clinical Psy.D program at The Chicago School of Professional Psychology completed a paper…
ERIC Educational Resources Information Center
Catalano, Richard F.; Haggerty, Kevin P.; Oesterle, Sabrina; Fleming, Charles B.; Hawkins, J. David
2004-01-01
This paper summarizes investigations of school connectedness completed by the Social Development Research Group in two longitudinal studies, the Seattle Social Development Project and Raising Healthy Children. The theoretical importance of school connectedness, empirical support for the theoretical propositions of the impact of school…
ERIC Educational Resources Information Center
Ritchey, Kristen D.; Coker, David L., Jr.; Jackson, Allison F.
2015-01-01
We investigated the relationship between 28 teachers' theoretical orientations to writing instruction and self-reported instructional practices and student writing performance. First-, second-, and third-grade teachers completed the Teacher Writing Orientation Scale developed by Graham, Harris, MacArthur, and Fink (2002) and reported the frequency…
HICOSMO - X-ray analysis of a complete sample of galaxy clusters
NASA Astrophysics Data System (ADS)
Schellenberger, G.; Reiprich, T.
2017-10-01
Galaxy clusters are known to be the largest virialized objects in the Universe. Based on the theory of structure formation one can use them as cosmological probes, since they originate from collapsed overdensities in the early Universe and witness its history. The X-ray regime provides the unique possibility to measure in detail the most massive visible component, the intra cluster medium. Using Chandra observations of a local sample of 64 bright clusters (HIFLUGCS) we provide total (hydrostatic) and gas mass estimates of each cluster individually. Making use of the completeness of the sample we quantify two interesting cosmological parameters by a Bayesian cosmological likelihood analysis. We find Ω_{M}=0.3±0.01 and σ_{8}=0.79±0.03 (statistical uncertainties) using our default analysis strategy combining both, a mass function analysis and the gas mass fraction results. The main sources of biases that we discuss and correct here are (1) the influence of galaxy groups (higher incompleteness in parent samples and a differing behavior of the L_{x} - M relation), (2) the hydrostatic mass bias (as determined by recent hydrodynamical simulations), (3) the extrapolation of the total mass (comparing various methods), (4) the theoretical halo mass function and (5) other cosmological (non-negligible neutrino mass), and instrumental (calibration) effects.
Denkova, Pavletta; Vassilev, Nikolay; Van Lokeren, Luk; Willem, Rudolph
2008-04-01
The static and dynamic stereochemistry of dimesityl-2,4,6-trimethoxyphenylmethane in solution was investigated by lineshape analysis of 1D NMR spectra and cross-peak amplitude processing in 2D EXSY spectra, recorded at variable temperatures. Previous studies on this propeller-shaped chiral compound show that the stereomer threshold interconversion is associated with helicity reversal and occurs through [1,2]- and [1,3]-two ring flips of one mesityl and the 2,4,6-trimethoxyphenyl rings. In the present study, the experimental rate constants of the [1,2]- and [1,3]-two ring flips, which are identical, were determined at various temperatures by combining quantitative 2D EXSY spectra processing and complete lineshape analysis (CLSA) of 1D NMR spectra. The latter were subjected to reference deconvolution and linear prediction in order to eliminate the lineshape distortions due to magnetic field inhomogeneity. The activation parameters of these ring flips were determined by an Eyring equation analysis of the temperature dependence of the rate constant. The experimentally determined activation enthalpy and entropy for the two-ring flips, and those obtained from theoretical ab initio calculations at different levels of theory and basis sets, were found to be in good agreement. Copyright (c) 2008 John Wiley & Sons, Ltd.
Comprehensive study of observables in Compton scattering on the nucleon
NASA Astrophysics Data System (ADS)
Grießhammer, Harald W.; McGovern, Judith A.; Phillips, Daniel R.
2018-03-01
We present an analysis of 13 observables in Compton scattering on the proton. Cross sections, asymmetries with polarised beam and/or targets, and polarisation-transfer observables are investigated for energies up to the Δ(1232) resonance to determine their sensitivity to the proton's dipole scalar and spin polarisabilities. The Chiral Effective Field Theory Compton amplitude we use is complete at N4LO, O(e2δ4), for photon energies ω˜ m_{π}, and so has an accuracy of a few per cent there. At photon energies in the resonance region, it is complete at NLO, O(e2δ0), and so its accuracy there is about 20%. We find that for energies from pion-production threshold to about 250 MeV, multiple asymmetries have significant sensitivity to presently ill-determined combinations of proton spin polarisabilities. We also argue that the broad outcomes of this analysis will be replicated in complementary theoretical approaches, e.g., dispersion relations. Finally, we show that below the pion-production threshold, 6 observables suffice to reconstruct the Compton amplitude, and above it 11 are required. Although not necessary for polarisability extractions, this opens the possibility to perform "complete" Compton-scattering experiments. An interactive Mathematica notebook, including results for the neutron, is available from judith.mcgovern@manchester.ac.uk.
Simple methods of exploiting the underlying structure of rule-based systems
NASA Technical Reports Server (NTRS)
Hendler, James
1986-01-01
Much recent work in the field of expert systems research has aimed at exploiting the underlying structures of the rule base for reasons of analysis. Such techniques as Petri-nets and GAGs have been proposed as representational structures that will allow complete analysis. Much has been made of proving isomorphisms between the rule bases and the mechanisms, and in examining the theoretical power of this analysis. In this paper we describe some early work in a new system which has much simpler (and thus, one hopes, more easily achieved) aims and less formality. The technique being examined is a very simple one: OPS5 programs are analyzed in a purely syntactic way and a FSA description is generated. In this paper we describe the technique and some user interface tools which exploit this structure.
Interactive program for analysis and design problems in advanced composites technology
NASA Technical Reports Server (NTRS)
Cruse, T. A.; Swedlow, J. L.
1971-01-01
During the past year an experimental program in the fracture of advanced fiber composites has been completed. The experimental program has given direction to additional experimental and theoretical work. A synthesis program for designing low weight multifastener joints in composites is proposed, based on extensive analytical background. A number of failed joints have been thoroughly analyzed to evaluate the failure hypothesis used in the synthesis procedure. Finally, a new solution is reported for isotropic and anisotropic laminates using the boundary-integral method. The solution method offers significant savings of computer core and time for important problems.
NASA Astrophysics Data System (ADS)
Campanari, Stefano; Mastropasqua, Luca; Gazzani, Matteo; Chiesa, Paolo; Romano, Matteo C.
2016-08-01
Driven by the search for the highest theoretical efficiency, in the latest years several studies investigated the integration of high temperature fuel cells in natural gas fired power plants, where fuel cells are integrated with simple or modified Brayton cycles and/or with additional bottoming cycles, and CO2 can be separated via chemical or physical separation, oxy-combustion and cryogenic methods. Focusing on Solid Oxide Fuel Cells (SOFC) and following a comprehensive review and analysis of possible plant configurations, this work investigates their theoretical potential efficiency and proposes two ultra-high efficiency plant configurations based on advanced intermediate-temperature SOFCs integrated with a steam turbine or gas turbine cycle. The SOFC works at atmospheric or pressurized conditions and the resulting power plant exceeds 78% LHV efficiency without CO2 capture (as discussed in part A of the work) and 70% LHV efficiency with substantial CO2 capture (part B). The power plants are simulated at the 100 MW scale with a complete set of realistic assumptions about fuel cell (FC) performance, plant components and auxiliaries, presenting detailed energy and material balances together with a second law analysis.
NASA Astrophysics Data System (ADS)
Barrios, Carlos Angulo; Canalejas-Tejero, Víctor
2017-01-01
The coupling efficiency at normal incidence of recently demonstrated aluminum grating couplers integrated in flexible Scotch tape waveguides has been analyzed theoretically and experimentally. Finite difference time domain (FDTD) and rigorously coupled wave analysis (RCWA) methods have been used to optimize the dimensions (duty cycle and metal thickness) of Scotch tape-embedded 1D Al gratings for maximum coupling at 635 nm wavelength. Good dimension and tape refractive index tolerances are predicted. FDTD simulations reveal the incident beam width and impinging position (alignment) values that avoid rediffraction and thus maximize the coupling efficiency. A 1D Al diffraction grating integrated into a Scotch tape optical waveguide has been fabricated and characterized. The fabrication process, based on pattern transfer, has been optimized to allow complete Al grating transfer onto the Scotch tape waveguide. A maximum coupling efficiency of 20% for TM-polarized normal incidence has been measured, which is in good agreement with the theoretical predictions. The measured coupling efficiency is further increased up to 28% for TM polarization under oblique incidence. Temperature dependence measurements have been also achieved and related to the simulations results and fabrication procedure.
Balachandran, V; Janaki, A; Nataraj, A
2014-01-24
The Fourier-Transform infrared and Fourier-Transform Raman spectra of thiophene-2-carbohydrazide (TCH) was recorded in the region 4000-400 cm(-1) and 3500-100 cm(-1). Quantum chemical calculations of energies, geometrical structure and vibrational wavenumbers of TCH were carried out by DFT (B3LYP) method with 6-311++G(d,p) as basis set. The difference between the observed and scaled wavenumber values of most of the fundamentals is very small. Stability of the molecule arising from hyper conjugative interaction and charge delocalization has been analyzed using natural bond orbital (NBO) analysis. UV spectrum was measured in different solvent. The energy and oscillator strength are calculated by Time Dependant Density Functional Theory (TD-DFT) results. The calculated HOMO and LUMO energies also confirm that charge transfer occurs within the molecule. The complete assignments were performed on the basis of the potential energy distribution (PED) of vibrational modes, calculated with scaled quantum mechanics (SQM) method. Finally the theoretical FT-IR, FT-Raman, and UV spectra of the title molecule have also been constructed. Copyright © 2013 Elsevier B.V. All rights reserved.
[Cognitive Reserve Scale: testing the theoretical model and norms].
Leon-Estrada, I; Garcia-Garcia, J; Roldan-Tapia, L
2017-01-01
The cognitive reserve theory may contribute to explain cognitive performance differences among individuals with similar cognitive decline and among healthy ones. However, more psychometric analysis are needed to guarantee the usage of tests for assessing cognitive reserve. To study validity evidences in relation to the structure of the Cognitive Reserve Scale (CRS) and to create reference norms to interpret the scores. A total of 172 participants completed the scale and they were classified into two age groups: aged 36-64 years (n = 110) and 65-88 years (n = 62). The exploratory factor analysis using ESEM revealed that the data fitted the proposed model. Overall, the discriminative indices were acceptable (between 0.21 and 0.50) and congruence was observed in the periods of young adulthood, adulthood and late adulthood, in both age group. Besides, the index of reliability (Cronbach's alpha: 0.80) and the typical mean error test (mean: 51.40 ± 11.11) showed adequate values for this type of instrument. The CRS seemed to be set under the hypothetical theoretical model, and the scores might be interpreted by the norms showed. This study provided guarantees for the usage of the CRS in research.
Education and the Quest for Human Completion: The African and Afro-American Perspectives Compared.
ERIC Educational Resources Information Center
Mungazi, Dickson A.
This paper examines the concept of human completion, as applied to both the African and the Afro-American experience, and how the search for completion by the individual influences the collective society. The theoretical concepts of Paulo Freire and Albert Memmi are applied to both groups. Both groups have been denied equal opportunity for…
Rosen, G D
2006-06-01
Meta-analysis is a vague descriptor used to encompass very diverse methods of data collection analysis, ranging from simple averages to more complex statistical methods. Holo-analysis is a fully comprehensive statistical analysis of all available data and all available variables in a specified topic, with results expressed in a holistic factual empirical model. The objectives and applications of holo-analysis include software production for prediction of responses with confidence limits, translation of research conditions to praxis (field) circumstances, exposure of key missing variables, discovery of theoretically unpredictable variables and interactions, and planning future research. Holo-analyses are cited as examples of the effects on broiler feed intake and live weight gain of exogenous phytases, which account for 70% of variation in responses in terms of 20 highly significant chronological, dietary, environmental, genetic, managemental, and nutrient variables. Even better future accountancy of variation will be facilitated if and when authors of papers routinely provide key data for currently neglected variables, such as temperatures, complete feed formulations, and mortalities.
NASA Astrophysics Data System (ADS)
Arjunan, V.; Anitha, R.; Marchewka, M. K.; Mohan, S.; Yang, Haifeng
2015-01-01
The Fourier transform infrared (FTIR) and FT-Raman spectra of cis-2-methoxycinnamic acid have been measured in the range 4000-400 and 4000-100 cm-1, respectively. Complete vibrational assignment and analysis of the fundamental modes of the compound were carried out using the observed FTIR and FT-Raman data. The geometry was optimised without any symmetry constrains using the DFT/B3LYP method utilising 6-311++G∗∗ and cc-pVTZ basis sets. The thermodynamic stability and chemical reactivity descriptors of the molecule have been determined. The exact environment of C and H of the molecule has been analysed by NMR spectroscopies through 1H and 13C NMR chemical shifts of the molecule. The energies of the frontier molecular orbitals have also been determined. Complete NBO analysis was also carried out to find out the intramolecular electronic interactions and their stabilisation energy. The vibrational frequencies which were determined experimentally are compared with those obtained theoretically from density functional theory (DFT) gradient calculations employing the B3LYP/6-311++G∗∗ and cc-pVTZ methods.
Physical Violence between Siblings: A Theoretical and Empirical Analysis
ERIC Educational Resources Information Center
Hoffman, Kristi L.; Kiecolt, K. Jill; Edwards, John N.
2005-01-01
This study develops and tests a theoretical model to explain sibling violence based on the feminist, conflict, and social learning theoretical perspectives and research in psychology and sociology. A multivariate analysis of data from 651 young adults generally supports hypotheses from all three theoretical perspectives. Males with brothers have…
The magnetisation distribution of the Ising model - a new approach
NASA Astrophysics Data System (ADS)
Hakan Lundow, Per; Rosengren, Anders
2010-03-01
A completely new approach to the Ising model in 1 to 5 dimensions is developed. We employ a generalisation of the binomial coefficients to describe the magnetisation distributions of the Ising model. For the complete graph this distribution is exact. For simple lattices of dimensions d=1 and d=5 the magnetisation distributions are remarkably well-fitted by the generalized binomial distributions. For d=4 we are only slightly less successful, while for d=2,3 we see some deviations (with exceptions!) between the generalized binomial and the Ising distribution. The results speak in favour of the generalized binomial distribution's correctness regarding their general behaviour in comparison to the Ising model. A theoretical analysis of the distribution's moments also lends support their being correct asymptotically, including the logarithmic corrections in d=4. The full extent to which they correctly model the Ising distribution, and for which graph families, is not settled though.
Low-cost solar array progress and plans
NASA Astrophysics Data System (ADS)
Callaghan, W. T.
It is pointed out that significant redirection has occurred in the U.S. Department of Energy (DOE) Photovoltaics Program, and thus in the Flat-Plate Solar Array Project (FSA), since the 3rd European Communities Conference. The Silicon Materials Task has now the objective to sponsor theoretical and experimental research on silicon material refinement technology suitable for photovoltaic flat-plate solar arrays. With respect to the hydrochlorination reaction, a process proof of concept was completed through definition of reaction kinetics, catalyst, and reaction characteristics. In connection with the dichlorosilane chemical vapor desposition process, a preliminary design was completed of an experimental process system development unit with a capacity of 100 to 200 MT/yr of Si.Attention is also given to the silicon-sheet formation research area, environmental isolation research, the cell and module formation task, the engineering sciences area, and the module performance and failure analysis area.
Structure, IR and Raman spectra of phosphotrihydrazide studied by DFT
NASA Astrophysics Data System (ADS)
Furer, V. L.; Vandyukov, A. E.; Majoral, J. P.; Caminade, A. M.; Kovalenko, V. I.
2016-09-01
The FTIR and FT Raman measurements of the phosphotrihydrazide (S)P[N(Me)-NH2]3 have been performed. This compound is a zero generation dendrimer G0 with terminal amine groups. Structural optimization and normal mode analysis were obtained for G0 by the density functional theory (DFT). Optimized geometric bond length and angles obtained by DFT show good agreement with experiment. The amine terminal groups are characterized by the well-defined bands at 3321, 3238, 1614 cm- 1 in the experimental IR spectrum and by bands at 3327, 3241 cm- 1 in the Raman spectrum of G0. The experimental frequencies of asymmetric and symmetric NH2 stretching vibrations of amine group are lower than theoretical values due to intramolecular Nsbnd H ⋯ S hydrogen bond. This hydrogen bond is also responsible for higher experimental infrared intensity of these bands as compared with theoretical values. Relying on DFT calculations a complete vibrational assignment is proposed for the studied dendrimer.
NASA Astrophysics Data System (ADS)
Subashchandrabose, S.; Ramesh Babu, N.; Saleem, H.; Syed Ali Padusha, M.
2015-08-01
The (E)-1-((pyridine-2-yl)methylene)semicarbazide (PMSC) was synthesized. The experimental and theoretical study on molecular structure and vibrational spectra were carried out. The FT-IR (400-4000 cm-1), FT-Raman (50-3500 cm-1) and UV-Vis (200-500 nm) spectra of PMSC were recorded. The geometric structure, conformational analysis, vibrational wavenumbers of PMSC in the ground state have been calculated using B3LYP method of 6-311++G(d,p) basis set. The complete vibrational assignments were made on the basis of TED, calculated by SQM method. The Non-linear optical activity was measured by means of first order hyperpolarizability calculation and π-electrons of conjugative bond in the molecule. The intra-molecular charge transfer, mode hyperconjugative interaction and molecular stabilization energies were calculated. The band gap energies between occupied and unoccupied molecular orbitals were analyzed; it proposes lesser band gap with more reactivity. To understand the electronic properties of this molecule the Mulliken charges were also calculated.
Extension of the hole-drilling method to birefringent composites
NASA Technical Reports Server (NTRS)
Prabhakaran, R.
1982-01-01
A complete stress analysis and reliable failure criteria are essential for important structural applications of composites in order to fully utilize their unique properties. The inhomogeneity, anisotropy and inelasticity of many composites make the use of experimental methods indispensable. Among the experimental techniques, transmission photoelasticity has been extended to birefringent composites in recent years. The extension is not straight-forward, in view of the complex nature of the photoelastic response of such model materials. This paper very briefly reviews the important developments in the subject and then describes the theoretical basis for a new method of determining the individual values of principal stresses in composite models. The method consists in drilling very small holes at points where the state of stress has to be determined. Experiments are then described which verify the theoretical predictions. The limitations of the method are pointed out and it is concluded that valuable information concerning the state of stress in a composite model can be obtained through the suggested method.
NASA Astrophysics Data System (ADS)
Khan, Shehryar; Kubica-Misztal, Aleksandra; Kruk, Danuta; Kowalewski, Jozef; Odelius, Michael
2015-01-01
The zero-field splitting (ZFS) of the electronic ground state in paramagnetic ions is a sensitive probe of the variations in the electronic and molecular structure with an impact on fields ranging from fundamental physical chemistry to medical applications. A detailed analysis of the ZFS in a series of symmetric Gd(III) complexes is presented in order to establish the applicability and accuracy of computational methods using multiconfigurational complete-active-space self-consistent field wave functions and of density functional theory calculations. The various computational schemes are then applied to larger complexes Gd(III)DOTA(H2O)-, Gd(III)DTPA(H2O)2-, and Gd(III)(H2O)83+ in order to analyze how the theoretical results compare to experimentally derived parameters. In contrast to approximations based on density functional theory, the multiconfigurational methods produce results for the ZFS of Gd(III) complexes on the correct order of magnitude.
The spatial configuration of ordered polynucleotide chains. II. The poly(rA) helix.
Olson, W K
1975-01-01
Approximate details of the spatial configuration of the ordered single-stranded poly(rA) molecule in dilute solution have been obtained in a combined theoretical analysis of base stacking and chain flexibility. Only those regularly repeating structures which fulfill the criterion of conformational flexibility (based upon all available experimental and theoretical evidence of preferred bond rotations) and which also exhibit the right-handed base stacking pattern observed in nmr investigations of poly(rA) are deemed suitable single-stranded helices. In addition, the helical geometry of the stacked structures is required to be consistent with the experimentally observed dimensions of both completely ordered and partially ordered poly(rA) chains. Only a single category of poly(rA) helices (very similar in all conformational details to the individual chains of the poly(rA) double-stranded X-ray structure) is thus obtained. Other conformationally feasible polynucleotide helices characterized simply by a parallel and overlapping base stacking arrangement are also discussed. PMID:1052529
Zhao, Yi-Lei; Flora, Jason W; Thweatt, William David; Garrison, Stephen L; Gonzalez, Carlos; Houk, K N; Marquez, Manuel
2009-02-02
A yellow solid material [P(x)H(y)] has been obtained in the reaction of phosphine (PH(3)) and nitric oxide (NO) at room temperature and characterized by thermogravimetric analysis mass spectrometry (TGA-MS) and attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy. In this work using complete basis set (CBS-QB3) methods a plausible mechanism has been investigated for phosphine polymerization in the presence of nitric oxide (NO). Theoretical explorations with the ab initio method suggest (a) instead of the monomer the nitric oxide dimer acts as an initial oxidant, (b) the resulting phosphine oxides (H(3)P=O <--> H(3)P(+)O(-)) in the gas phase draw each other via strong dipolar interactions between the P-O groups, and (c) consequently an autocatalyzed polymerization occurs among the phosphine oxides, forming P-P chemical bonds and losing water. The possible structures of polyhydride phosphorus polymer were discussed. In the calculations a series of cluster models was computed to simulate polymerization.
Tsuchiya, Y
2001-08-01
A concise theoretical treatment has been developed to describe the optical responses of a highly scattering inhomogeneous medium using functions of the photon path distribution (PPD). The treatment is based on the microscopic Beer-Lambert law and has been found to yield a complete set of optical responses by time- and frequency-domain measurements. The PPD is defined for possible photons having a total zigzag pathlength of l between the points of light input and detection. Such a distribution is independent of the absorption properties of the medium and can be uniquely determined for the medium under quantification. Therefore, the PPD can be calculated with an imaginary reference medium having the same optical properties as the medium under quantification except for the absence of absorption. One of the advantages of this method is that the optical responses, the total attenuation, the mean pathlength, etc are expressed by functions of the PPD and the absorption distribution.
Theoretical study of the transonic lift of a double-wedge profile with detached bow wave
NASA Technical Reports Server (NTRS)
Vincenti, Walter G; Wagoner, Cleo B
1954-01-01
A theoretical study is described of the aerodynamic characteristics at small angle of attack of a thin, double-wedge profile in the range of supersonic flight speed in which the bow wave is detached. The analysis is carried out within the framework of the transonic (nonlinear) small-disturbance theory, and the effects of angle of attack are regarded as a small perturbation on the flow previously calculated at zero angle. The mixed flow about the front half of the profile is calculated by relaxation solution of a suitably defined boundary-value problem for transonic small-disturbance equation in the hodograph plane (i.e., the Tricomi equation). The purely supersonic flow about the rear half is found by an extension of the usual numerical method of characteristics. Analytical results are also obtained, within the framework of the same theory, for the range of speed in which the bow wave is attached and the flow is completely supersonic.
Jha, Manish Kumar; Minhajuddin, Abu; Thase, Michael E.; Jarrett, Robin B.
2014-01-01
Background Major Depressive Disorder is common, often recurrent and/or chronic. Theoretically, assessing quality of life (QoL) in addition to the current practice of assessing depressive symptoms has the potential to offer a more comprehensive evaluation of the effects of treatment interventions and course of illness. Methods Before and after acute-phase cognitive therapy (CT), 492 patients from Continuation Phase Cognitive Therapy Relapse Prevention trial (Jarrett et al., 2013, Jarrett and Thase, 2010) completed the Quality of Life Enjoyment and Satisfaction Questionnaire (Q-LES-Q), Inventory of Depressive Symptomatology Self-report (IDS-SR) & Beck Depression Inventory (BDI); clinicians completed Hamilton Rating Scale for Depression-17-items. Repeated measures analysis of variance evaluated the improvement in QoL before/after CT and measured the effect sizes. Change analyses to assess clinical significance (Hageman and Arrindell, 1999) were conducted. Results At the end of acute-phase CT, a repeated measure analysis of variance produced a statistically significant increase in Q-LES-Q scores with effect sizes of 0.48 - 1.3; 76.9 - 91.4% patients reported clinically significant improvement. Yet, only 11 - 38.2% QoL scores normalized. An analysis of covariance showed that change in depression severity (covariates=IDS-SR, BDI) completely accounted for the improvement in Q-LES-Q scores. Limitations There were only two time points of observation; clinically significant change analyses lacked matched normal controls; and generalizability is constrained by sampling characteristics. Conclusions: Quality of life improves significantly in patients with recurrent MDD after CT; however, this improvement is completely accounted for by change in depression severity. Normalization of QoL in all patients may require targeted, additional, and/or longer treatment. PMID:25082112
Jha, Manish Kumar; Minhajuddin, Abu; Thase, Michael E; Jarrett, Robin B
2014-01-01
Major depressive disorder (MDD) is common, often recurrent and/or chronic. Theoretically, assessing quality of life (QoL) in addition to the current practice of assessing depressive symptoms has the potential to offer a more comprehensive evaluation of the effects of treatment interventions and course of illness. Before and after acute-phase cognitive therapy (CT), 492 patients from Continuation Phase Cognitive Therapy Relapse Prevention trial (Jarrett et al., 2013; Jarrett and Thase, 2010) completed the Quality of Life Enjoyment and Satisfaction Questionnaire (Q-LES-Q), Inventory of Depressive Symptomatology Self-report (IDS-SR) and Beck Depression Inventory (BDI); clinicians completed Hamilton Rating Scale for Depression-17-items. Repeated measures analysis of variance evaluated the improvement in QoL before/after CT and measured the effect sizes. Change analyses to assess clinical significance (Hageman and Arrindell, 1999) were conducted. At the end of acute-phase CT, a repeated measure analysis of variance produced a statistically significant increase in Q-LES-Q scores with effect sizes of 0.48-1.3%; 76.9-91.4% patients reported clinically significant improvement. Yet, only 11-38.2% QoL scores normalized. An analysis of covariance showed that change in depression severity (covariates=IDS-SR, BDI) completely accounted for the improvement in Q-LES-Q scores. There were only two time points of observation; clinically significant change analyses lacked matched normal controls; and generalizability is constrained by sampling characteristics. Quality of life improves significantly in patients with recurrent MDD after CT; however, this improvement is completely accounted for by change in depression severity. Normalization of QoL in all patients may require targeted, additional, and/or longer treatment. Copyright © 2014 Elsevier B.V. All rights reserved.
Fate of heavy metals during municipal solid waste incineration.
Abanades, S; Flamant, G; Gagnepain, B; Gauthier, D
2002-02-01
A thermodynamic analysis was performed to determine whether it is suitable to predict the heavy metal (HM) speciation during the Municipal Solid Waste Incineration process. The fate of several selected metals (Cd, Pb, Zn, Cr, Hg, As, Cu, Co, Ni) during incineration was theoretically investigated. The equilibrium analysis predicted the metal partitioning during incineration and determined the impact of operating conditions (temperature and gas composition) on their speciation. The study of the gas composition influence was based on the effects of the contents of oxygen (reducing or oxidising conditions) and chlorine on the HM partitioning. The theoretical HM speciation which was calculated in a complex system representing a burning sample of Municipal Solid Waste can explain the real partitioning (obtained from literature results) of all metals among the various ashes except for Pb. Then, the results of the thermodynamic study were compared with those of characterisation of real incinerator residues, using complementary techniques (chemical extraction series and X-ray micro-analyses). These analysis were performed to determine experimentally the speciation of the three representative metals Cr, Pb, and Zn. The agreement is good for Cr and Zn but not for Pb again, which mainly shows unleachable chemical speciations in the residues. Pb tends to remain in the bottom ash whereas thermodynamics often predicts its complete volatilisation under chlorides, and thus its presence exclusively in fly ash.
Light aircraft lift, drag, and moment prediction: A review and analysis
NASA Technical Reports Server (NTRS)
Smetana, F. O.; Summey, D. C.; Smith, N. S.; Carden, R. K.
1975-01-01
The historical development of analytical methods for predicting the lift, drag, and pitching moment of complete light aircraft configurations in cruising flight is reviewed. Theoretical methods, based in part on techniques described in the literature and in part on original work, are developed. These methods form the basis for understanding the computer programs given to: (1) compute the lift, drag, and moment of conventional airfoils, (2) extend these two-dimensional characteristics to three dimensions for moderate-to-high aspect ratio unswept wings, (3) plot complete configurations, (4) convert the fuselage geometric data to the correct input format, (5) compute the fuselage lift and drag, (6) compute the lift and moment of symmetrical airfoils to M = 1.0 by a simplified semi-empirical procedure, and (7) compute, in closed form, the pressure distribution over a prolate spheroid at alpha = 0. Comparisons of the predictions with experiment indicate excellent lift and drag agreement for conventional airfoils and wings. Limited comparisons of body-alone drag characteristics yield reasonable agreement. Also included are discussions for interference effects and techniques for summing the results above to obtain predictions for complete configurations.
Impact of Functionally Graded Cylinders: Theory
NASA Technical Reports Server (NTRS)
Aboudi, Jacob; Pindera, Marek-Jerzy; Arnold, S. M. (Technical Monitor)
2001-01-01
This final report summarizes the work funded under the Grant NAG3-2411 during the 04/05/2000-04/04/2001 period. The objective of this one-year project was to generalize the theoretical framework of the two-dimensional higher-order theory for the analysis of cylindrical functionally graded materials/structural components employed in advanced aircraft engines developed under past NASA Glenn funding. The completed generalization significantly broadens the theory's range of applicability through the incorporation of dynamic impact loading capability into its framework. Thus, it makes possible the assessment of the effect of damage due to fuel impurities, or the presence of submicron-level debris, on the life of functionally graded structural components. Applications involving advanced turbine blades and structural components for the reusable-launch vehicle (RLV) currently under development will benefit from the completed work. The theory's predictive capability is demonstrated through a numerical simulation of a one-dimensional wave propagation set up by an impulse load in a layered half-plane. Full benefit of the completed generalization of the higher-order theory described in this report will be realized upon the development of a related computer code.
Chia -Hsun Chuang; Pellejero-Ibanez, Marco; Rodriguez-Torres, Sergio; ...
2016-06-26
We analyze the broad-range shape of the monopole and quadrupole correlation functions of the BOSS Data Release 12 (DR12) CMASS and LOWZ galaxy sample to obtain constraints on the Hubble expansion rate H(z), the angular-diameter distance DA(z), the normalised growth rate f(z)σ 8(z), and the physical matter density Ω mh 2. In addition, we adopt wide and flat priors on all model parameters in order to ensure the results are those of a `single-probe' galaxy clustering analysis. We also marginalize over three nuisance terms that account for potential observational systematics affecting the measured monopole. However, such Monte Carlo Markov Chainmore » analysis is computationally expensive for advanced theoretical models, thus we develop a new methodology to speed up our analysis.« less
Student design projects in applied acoustics.
Bös, Joachim; Moritz, Karsten; Skowronek, Adam; Thyes, Christian; Tschesche, Johannes; Hanselka, Holger
2012-03-01
This paper describes a series of student projects which are intended to complement theoretical education in acoustics and engineering noise control with practical experience. The projects are also intended to enhance the students' ability to work in a team, to manage a project, and to present their results. The projects are carried out in close cooperation with industrial partners so that the students can get a taste of the professional life of noise control engineers. The organization of such a project, its execution, and some of the results from the most recent student project are presented as a demonstrative example. This latest project involved the creation of noise maps of a production hall, the acoustic analysis of a packaging machine, and the acoustic analysis of a spiral vibratory conveyor. Upon completion of the analysis, students then designed, applied, and verified some simple preliminary noise reduction measures to demonstrate the potential of these techniques. © 2012 Acoustical Society of America
Rajesh, P; Gunasekaran, S; Gnanasambandan, T; Seshadri, S
2015-02-25
The complete vibrational assignment and analysis of the fundamental vibrational modes of Trifluoperazine (TFZ) was carried out using the experimental FT-IR, FT-Raman and UV-Vis data and quantum chemical studies. The observed vibrational data were compared with the wavenumbers derived theoretically for the optimized geometry of the compound from the DFT-B3LYP gradient calculations employing 6-31G (d,p) basis set. Thermodynamic properties like entropy, heat capacity and enthalpy have been calculated for the molecule. The HOMO-LUMO energy gap has been calculated. The intramolecular contacts have been interpreted using natural bond orbital (NBO) and natural localized molecular orbital (NLMO) analysis. Important non-linear properties such as first hyperpolarizability of TFZ have been computed using B3LYP quantum chemical calculation. Copyright © 2014 Elsevier B.V. All rights reserved.
Ernst, Marielle; Kriston, Levente; Romero, Javier M; Frölich, Andreas M; Jansen, Olav; Fiehler, Jens; Buhk, Jan-Hendrik
2016-01-01
We sought to develop a standardized curriculum capable of assessing key competencies in Interventional Neuroradiology by the use of models and simulators in an objective, quantitative, and efficient way. In this evaluation we analyzed the associations between the practical experience, theoretical knowledge, and the skills lab performance of interventionalists. We evaluated the endovascular skills of 26 participants of the Advanced Course in Endovascular Interventional Neuroradiology of the European Society of Neuroradiology with a set of three tasks (aneurysm coiling and thrombectomy in a virtual simulator and placement of an intra-aneurysmal flow disruptor in a flow model). Practical experience was assessed by a survey. Participants completed a written and oral examination to evaluate theoretical knowledge. Bivariate and multivariate analyses were performed. In multivariate analysis knowledge of materials and techniques in Interventional Neuroradiology was moderately associated with skills in aneurysm coiling and thrombectomy. Experience in mechanical thrombectomy was moderately associated with thrombectomy skills, while age was negatively associated with thrombectomy skills. We found no significant association between age, sex, or work experience and skills in aneurysm coiling. Our study gives an example of how an integrated curriculum for reasonable and cost-effective assessment of key competences of an interventional neuroradiologist could look. In addition to traditional assessment of theoretical knowledge practical skills are measured by the use of endovascular simulators yielding objective, quantitative, and constructive data for the evaluation of the current performance status of participants as well as the evolution of their technical competency over time.
Hmiel, A.; Winey, J. M.; Gupta, Y. M.; ...
2016-05-23
Accurate theoretical calculations of the nonlinear elastic response of strong solids (e.g., diamond) constitute a fundamental and important scientific need for understanding the response of such materials and for exploring the potential synthesis and design of novel solids. However, without corresponding experimental data, it is difficult to select between predictions from different theoretical methods. Recently the complete set of third-order elastic constants (TOECs) for diamond was determined experimentally, and the validity of various theoretical approaches to calculate the same may now be assessed. We report on the use of density functional theory (DFT) methods to calculate the six third-order elasticmore » constants of diamond. Two different approaches based on homogeneous deformations were used: (1) an energy-strain fitting approach using a prescribed set of deformations, and (2) a longitudinal stress-strain fitting approach using uniaxial compressive strains along the [100], [110], and [111] directions, together with calculated pressure derivatives of the second-order elastic constants. The latter approach provides a direct comparison to the experimental results. The TOECs calculated using the energy-strain approach differ significantly from the measured TOECs. In contrast, calculations using the longitudinal stress-uniaxial strain approach show good agreement with the measured TOECs and match the experimental values significantly better than the TOECs reported in previous theoretical studies. Lastly, our results on diamond have demonstrated that, with proper analysis procedures, first-principles calculations can indeed be used to accurately calculate the TOECs of strong solids.« less
Control Coordination of Multiple Agents Through Decision Theoretic and Economic Methods
2003-02-01
instructions, searching existing data sources, gathering and maintaining the data needed, and completing and reviewing this collection of information...investigated the design of test data for benchmarking such optimization algorithms. Our other research on combinatorial auctions included I...average combination rule. We exemplified these theoretical results with experiments on stock market data , demonstrating how ensembles of classifiers can
ERIC Educational Resources Information Center
Haj-Yahia, Muhammad M.; Uysal, Aynur
2011-01-01
An integrative theoretical framework was tested as the basis for explaining beliefs about wife beating among Turkish nursing students. Based on a survey design, 406 nursing students (404 females) in all 4 years of undergraduate studies completed a self-administered questionnaire. Questionnaires were distributed and collected from the participants…
Jippes, Mariëlle; Driessen, Erik W; Broers, Nick J; Majoor, Gerard D; Gijselaers, Wim H; van der Vleuten, Cees P M
2013-09-01
Because successful change implementation depends on organizational readiness for change, the authors developed and assessed the validity of a questionnaire, based on a theoretical model of organizational readiness for change, designed to measure, specifically, a medical school's organizational readiness for curriculum change (MORC). In 2012, a panel of medical education experts judged and adapted a preliminary MORC questionnaire through a modified Delphi procedure. The authors administered the resulting questionnaire to medical school faculty involved in curriculum change and tested the psychometric properties using exploratory and confirmatory factor analysis, and generalizability analysis. The mean relevance score of the Delphi panel (n = 19) reached 4.2 on a five-point Likert-type scale (1 = not relevant and 5 = highly relevant) in the second round, meeting predefined criteria for completing the Delphi procedure. Faculty (n = 991) from 131 medical schools in 56 countries completed MORC. Exploratory factor analysis yielded three underlying factors-motivation, capability, and external pressure-in 12 subscales with 53 items. The scale structure suggested by exploratory factor analysis was confirmed by confirmatory factor analysis. Cronbach alpha ranged from 0.67 to 0.92 for the subscales. Generalizability analysis showed that the MORC results of 5 to 16 faculty members can reliably evaluate a school's organizational readiness for change. MORC is a valid, reliable questionnaire for measuring organizational readiness for curriculum change in medical schools. It can identify which elements in a change process require special attention so as to increase the chance of successful implementation.
Graphene-Based Liquid-Gated Field Effect Transistor for Biosensing: Theory and Experiments
Reiner-Rozman, Ciril; Larisika, Melanie; Nowak, Christoph; Knoll, Wolfgang
2015-01-01
We present an experimental and theoretical characterization for reduced Graphene-Oxide (rGO) based FETs used for biosensing applications. The presented approach shows a complete result analysis and theoretically predictable electrical properties. The formulation was tested for the analysis of the device performance in the liquid gate mode of operation with variation of the ionic strength and pH-values of the electrolytes in contact with the FET. The dependence on the Debye length was confirmed experimentally and theoretically, utilizing the Debye length as a working parameter and thus defining the limits of applicability for the presented rGO-FETs. Furthermore, the FETs were tested for the sensing of biomolecules (bovine serum albumin (BSA) as reference) binding to gate-immobilized anti-BSA antibodies and analyzed using the Langmuir binding theory for the description of the equilibrium surface coverage as a function of the bulk (analyte) concentration. The obtained binding coefficients for BSA are found to be same as in results from literature, hence confirming the applicability of the devices. The FETs used in the experiments were fabricated using wet-chemically synthesized graphene, displaying high electron and hole mobility (μ) and provide the strong sensitivity also for low potential changes (by change of pH, ion concentration, or molecule adsorption). The binding coefficient for BSA-anti-BSA interaction shows a behavior corresponding to the Langmuir adsorption theory with a Limit of Detection (LOD) in the picomolar concentration range. The presented approach shows high reproducibility and sensitivity and a good agreement of the experimental results with the calculated data. PMID:25791463
Ghisi, Gabriela Lima de Melo; Grace, Sherry L; Thomas, Scott; Oh, Paul
2015-05-01
To (1) test the effect of a health action process approach (HAPA) theory-based education program in cardiac rehabilitation (CR) compared to traditional education on patient knowledge and HAPA constructs; and, (2) investigate the theoretical correlates of exercise behavior among CR patients receiving theory-based education. CR patients were exposed to an existing or HAPA-based 6 month education curriculum in this quasi-experimental study. Participants completed a survey assessing exercise behavior, HAPA constructs, and knowledge pre and post-program. 306 patients consented to participate, of which 146 (47.7%) were exposed to the theory-based educational curriculum. There was a significant improvement in patients' overall knowledge pre- to post-CR, as well as in some HAPA constructs and exercise behavior, regardless of curriculum (p < 0.05). Path analysis revealed that knowledge was significantly related to intention formation, and intentions to engage in exercise were not directly related to behavior, which required action planning. The theoretically-informed education curriculum was not associated with greater knowledge or exercise behavior as expected. Education in CR improves knowledge, and theoretical constructs related to exercise behavior. Educational curricula should be designed to not only increase patients' knowledge, but also enhance intentions, self-efficacy, and action planning. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.
Yilmaz, Ozge; Can, Zehra S; Toroz, Ismail; Dogan, Ozgur; Oncel, Salim; Alp, Emre; Dilek, Filiz B; Karanfil, Tanju; Yetis, Ulku
2014-08-01
Hazardous waste (HW) generation information is an absolute necessity for ensuring the proper planning, implementation, and monitoring of any waste management system. Unfortunately, environmental agencies in developing countries face difficulties in gathering data directly from the creators of such wastes. It is possible, however, to construct theoretical HW inventories using the waste generation factors (WGFs). The objective of this study was to develop a complete nationwide HW inventory of Turkey that relies on nation-specific WGFs to support management activities of the Turkish Ministry of Environment and Urbanization (MoEU). Inventory studies relied on WGFs from: (a) the literature and (b) field studies and analysis of waste declarations reflecting country-specific industrial practices. Moreover, new tools were introduced to the monitoring infrastructure of MoEU to obtain a comprehensive waste generation data set. Through field studies and a consideration of country specific conditions, it was possible to more thoroughly elucidate HW generation trends in Turkey, a method that was deemed superior to other alternatives. Declaration and literature based WGFs also proved most helpful in supplementing field observations that could not always be conducted. It was determined that these theoretical inventories could become valuable assets in supporting regulating agencies in developing countries for a more thorough implementation of HW management systems. © The Author(s) 2014.
NASA Astrophysics Data System (ADS)
Bao, Minle; Wang, Lu; Li, Wenyao; Gao, Tianze
2017-09-01
Fluid elastic excitation in shell side of heat exchanger was deduced theoretically in this paper. Model foundation was completed by using Pro / Engineer software. The finite element model was constructed and imported into the FLUENT module. The flow field simulation adopted the dynamic mesh model, RNG k-ε model and no-slip boundary conditions. Analysing different positions vibration of tube bundles by selecting three regions in shell side of heat exchanger. The results show that heat exchanger tube bundles at the inlet of the shell side are more likely to be failure due to fluid induced vibration.
Novel measurement techniques (development and analysis of silicon solar cells near 20% effciency)
NASA Technical Reports Server (NTRS)
Wolf, M.; Newhouse, M.
1986-01-01
Work in identifying, developing, and analyzing techniques for measuring bulk recombination rates, and surface recombination velocities and rates in all regions of high-efficiency silicon solar cells is presented. The accuracy of the previously developed DC measurement system was improved by adding blocked interference filters. The system was further automated by writing software that completely samples the unkown solar cell regions with data of numerous recombination velocity and lifetime pairs. The results can be displayed in three dimensions and the best fit can be found numerically using the simplex minimization algorithm. Also described is a theoretical methodology to analyze and compare existing dynamic measurement techniques.
Two-legged walking robot prescribed motion on a rough cylinder
NASA Astrophysics Data System (ADS)
Golubev, Yury; Melkumova, Elena
2018-05-01
The motion of a walking robot with n legs, that ensure the desired motion of the robot body, is described using general dynamics theoretical framework. When each of the robot legs contacts the surface in a single foothold, the momentum and angular momentum theorems yield a system of six differential equations that form a complete description of the robot motion. In the case of two-leg robot (n = 2) the problem of the existence of the solution can be reduced to a system of algebraic inequalities. Using numerical analysis, the classification of footholds positions for different values of the friction coefficient is obtained.
Development of simplified external control techniques for broad area semiconductor lasers
NASA Technical Reports Server (NTRS)
Davis, Christopher C.
1993-01-01
The goal of this project was to injection lock a 500 mW broad area laser diode (BAL) with a single mode low power laser diode with injection beam delivery through a single mode optical fiber (SMF). This task was completed successfully with the following significant accomplishments: (1) injection locking of a BAL through a single-mode fiber using a master oscillator and integrated miniature optics; (2) generation of a single-lobed, high-power far-field pattern from the injection-locked BAL that steers with drive current; and (3) a comprehensive theoretical analysis of a model that describes the observed behavior of the injection locked oscillator.
Gradient and size effects on spinodal and miscibility gaps
NASA Astrophysics Data System (ADS)
Tsagrakis, Ioannis; Aifantis, Elias C.
2018-05-01
A thermodynamically consistent model of strain gradient elastodiffusion is developed. Its formulation is based on the enhancement of a robust theory of gradient elasticity, known as GRADELA, to account for a Cahn-Hilliard type of diffusion. Linear stability analysis is employed to determine the influence of concentration and strain gradients on the spinodal decomposition. For finite domains, spherically symmetric conditions are considered, and size effects on spinodal and miscibility gaps are discussed. The theoretical predictions are in agreement with the experimental trends, i.e., both gaps shrink as the grain diameter decreases and they are completely eliminated for crystals smaller than a critical size.
Les résonances d'un trou noir de Schwarzschild.
NASA Astrophysics Data System (ADS)
Bachelot, A.; Motet-Bachelot, A.
1993-09-01
This paper is devoted to the theoretical and computational investigations of the scattering frequencies of scalar, electromagnetic, gravitational waves around a spherical black hole. The authors adopt a time dependent approach: construction of wave operators for the hyperbolic Regge-Wheeler equation; asymptotic completeness; outgoing and incoming spectral representations; meromorphic continuation of the Heisenberg matrix; approximation by dumping and cut-off of the potentials and interpretation of the semi group Z(t) in the framework of the membrane paradigma. They develop a new procedure for the computation of the resonances by the spectral analysis of the transient scattered wave, based on Prony's algorithm.
ADHD bifactor model based on parent and teacher ratings of Malaysian children.
Gomez, Rapson
2014-04-01
The study used confirmatory factor analysis to ascertain support for the bifactor model of the Attention Deficit/Hyperactivity Disorder (ADHD) symptoms, based on parent and teacher ratings for a group of Malaysian children. Malaysian parents and teachers completed ratings of ADHD and Opposition Defiant Disorder (ODD) symptoms for 934 children. For both sets of ratings, the findings indicating good fit for the bifactor model, and the factors in this model showed differential associations with ODD, thereby supporting the internal and external validity of this model. The theoretical and clinical implications of the findings are discussed. Copyright © 2013 Elsevier B.V. All rights reserved.
Novel measurement techniques (development and analysis of silicon solar cells near 20% effciency)
NASA Astrophysics Data System (ADS)
Wolf, M.; Newhouse, M.
Work in identifying, developing, and analyzing techniques for measuring bulk recombination rates, and surface recombination velocities and rates in all regions of high-efficiency silicon solar cells is presented. The accuracy of the previously developed DC measurement system was improved by adding blocked interference filters. The system was further automated by writing software that completely samples the unkown solar cell regions with data of numerous recombination velocity and lifetime pairs. The results can be displayed in three dimensions and the best fit can be found numerically using the simplex minimization algorithm. Also described is a theoretical methodology to analyze and compare existing dynamic measurement techniques.
NASA Astrophysics Data System (ADS)
Martins, Tiago; de Magalhães, Sérgio Tenreiro
The baby's crying is his most important mean of communication. The crying monitoring performed by devices that have been developed doesn't ensure the complete safety of the child. It is necessary to join, to these technological resources, means of communicating the results to the responsible, which would involve the digital processing of information available from crying. The survey carried out, enabled to understand the level of adoption, in the continental territory of Portugal, of a technology that will be able to do such a digital processing. It was used the TAM as the theoretical referential. The statistical analysis showed that there is a good probability of acceptance of such a system.
Theoretical aerodynamic characteristics of a family of slender wing-tail-body combinations
NASA Technical Reports Server (NTRS)
Lomax, Harvard; Byrd, Paul F
1951-01-01
The aerodynamic characteristics of an airplane configuration composed of a swept-back, nearly constant chord wing and a triangular tail mounted on a cylindrical body are presented. The analysis is based on the assumption that the free-stream Mach number is near unity or that the configuration is slender. The calculations for the tail are made on the assumption that the vortex system trailing back from the wing is either a sheet lying entirely in the plane of the flat tail surface or has completely "rolled up" into two point vortices that lie either in, above, or below the plane of the tail surface.
Influence of leadership on quality nursing care.
Mendes, Luis; Fradique, Maria de Jesus José Gil
2014-01-01
The purpose of this paper is to investigate the extent to which nursing leadership, perceived by nursing staff, influences nursing quality. Data were collected between August and October 2011 in a Portuguese health center via a questionnaire completed by nurses. Our original sample included 283 employees; 184 questionnaires were received (65% response). The theoretical model presents reasonably satisfactory fit indices (values above literature reference). Path analysis between latent constructs clearly suggests that nursing leadership has a direct (beta = 0.724) and statistically significant (p = 0.007) effect on nursing quality. Results reinforce several ideas propagated throughout the literature, which suggests the relationship's relevance, but lacks empirical support, which this study corrects.
Spiritual Health in Nursing From the Viewpoint of Islam.
Heydari, Abbas; Khorashadizadeh, Fatemeh; Heshmati Nabavi, Fatemeh; Mazlom, Seyed Reza; Ebrahimi, Mahdi
2016-06-01
In order to gain a more detailed insight into the concept of spiritual health, a hybrid model of concept analysis was used to remove some of the ambiguity surrounding the conceptual meaning of spiritual health in Islamic and Iranian contexts. The purpose of this study was to clarify the meaning and nature of the spiritual health concept in the context of the practice of Islam among Iranian patients. The current concept analysis was undertaken according to the modified traditional hybrid model, which consists of five phases: theoretical phase, initial fieldwork phase, initial analytical phase, and final fieldwork and final analytical phase. In the theoretical phases of the study, the concept of spiritual health was described based on a literature review of publications dealing with the Islamic viewpoint (years: from 2013 to 2014, Databases and search engines: Pubmed, SID, Magiran, Noormax, Google Scholar, Google and IranMex, Languages: English and Persian, Keywords: spiritual health AND (Islam OR Quran), spirituality AND (Islam OR Quran), complete human AND Islam, healthy heart (Galb Salim) AND Islam, healthy life (Hayat tayebeh) AND Islam, calm soul (Nafse motmaeneh) And Islam and healthy wisdom (Aghle Salim) AND Islam). Purposive sampling was conducted and nine participants were selected. Semi-structured interviews and observations were conducted periodically for data collection after obtaining informed consent. Observational, theoretical, and methodological notes were made. Then, using MAXQUDA 7 software, the data were analyzed using qualitative content analysis. The relevant literature in the theoretical phase uncovered the attributes of the concept of spiritual health, including love of the Creator, duty-based life, religious rationality, psychological balance, and attention to afterlife. These attributes were explored in depth in later stages. Finally, the definition of spiritual health was developed. Islam has a unique perspective on spiritual health as it encompasses all aspects of human beings. Thus, it is necessary to carefully study the difference between the Islamic concept of spiritual health and that of other religions and ideologies to design suitable and useful nursing care for Iranian patients that satisfy their spiritual needs.
Spiritual Health in Nursing From the Viewpoint of Islam
Heydari, Abbas; Khorashadizadeh, Fatemeh; Heshmati Nabavi, Fatemeh; Mazlom, Seyed Reza; Ebrahimi, Mahdi
2016-01-01
Context In order to gain a more detailed insight into the concept of spiritual health, a hybrid model of concept analysis was used to remove some of the ambiguity surrounding the conceptual meaning of spiritual health in Islamic and Iranian contexts. The purpose of this study was to clarify the meaning and nature of the spiritual health concept in the context of the practice of Islam among Iranian patients. Evidence Acquisition The current concept analysis was undertaken according to the modified traditional hybrid model, which consists of five phases: theoretical phase, initial fieldwork phase, initial analytical phase, and final fieldwork and final analytical phase. In the theoretical phases of the study, the concept of spiritual health was described based on a literature review of publications dealing with the Islamic viewpoint (years: from 2013 to 2014, Databases and search engines: Pubmed, SID, Magiran, Noormax, Google Scholar, Google and IranMex, Languages: English and Persian, Keywords: spiritual health AND (Islam OR Quran), spirituality AND (Islam OR Quran), complete human AND Islam, healthy heart (Galb Salim) AND Islam, healthy life (Hayat tayebeh) AND Islam, calm soul (Nafse motmaeneh) And Islam and healthy wisdom (Aghle Salim) AND Islam). Purposive sampling was conducted and nine participants were selected. Semi-structured interviews and observations were conducted periodically for data collection after obtaining informed consent. Observational, theoretical, and methodological notes were made. Then, using MAXQUDA 7 software, the data were analyzed using qualitative content analysis. Results The relevant literature in the theoretical phase uncovered the attributes of the concept of spiritual health, including love of the Creator, duty-based life, religious rationality, psychological balance, and attention to afterlife. These attributes were explored in depth in later stages. Finally, the definition of spiritual health was developed. Conclusions Islam has a unique perspective on spiritual health as it encompasses all aspects of human beings. Thus, it is necessary to carefully study the difference between the Islamic concept of spiritual health and that of other religions and ideologies to design suitable and useful nursing care for Iranian patients that satisfy their spiritual needs. PMID:27621915
2012-01-01
Background Technology-enhanced learning (TEL) gives a view to improved education. However, there is a need to clarify how TEL can be used effectively. The study compared students' attitudes and opinions towards a traditional face-to-face course on theoretical radiological science and a TEL course where students could combine face-to-face lectures and e-learning modules at their best convenience. Methods 42 third-year dental students were randomly assigned to the traditional face-to-face group and the TEL group. Both groups completed questionnaires before the beginning and after completion of the course on attitudes and opinions towards a traditional face-to-face lectures and technology-enhanced learning. After completion of the course both groups also filled in the validated German-language TRIL (Trierer Inventar zur Lehrevaluation) questionnaire for the evaluation of courses given at universities. Results Both groups had a positive attitude towards e-learning that did not change over time. The TEL group attended significantly less face-to-face lectures than the traditional group. However, both groups stated that face-to-face lectures were the basis for education in a theoretical radiological science course. The members of the TEL group rated e-mail reminders significantly more important when they filled in the questionnaire on attitudes and opinions towards a traditional face-to-face lectures and technology-enhanced learning for the second time after completion of the course. The members of the technology-enhanced learning group were significantly less confident in passing the exam compared to the members of the traditional group. However, examination results did not differ significantly for traditional and the TEL group. Conclusions It seems that technology-enhanced learning in a theoretical radiological science course has the potential to reduce the need for face-to-face lectures. At the same time examination results are not impaired. However, technology-enhanced learning cannot completely replace traditional face-to-face lectures, because students indicate that they consider traditional teaching as the basis of their education. PMID:22463757
NASA Technical Reports Server (NTRS)
Lin, Robert P.
1988-01-01
Participation of U.S. scientists on the COPERNIC (COmplete Positive ions, Electrons and Ram Negative Ion measurements near Comet Halley) plasma experiment on the Giotto mission is described. The experiment consisted of two detectors: the EESA (electron electrostatic analyzer) which provided three-dimensional measurements of the distribution of electrons from 10 eV to 30 keV, and the PICCA (positive ion cluster composition analyzer) which provided mass analysis of positively charged cold cometary ions from mass 10 to 210 amu. In addition, a small 3 deg wide sector of the EESA looking in the ram direction was devoted to the detection of negatively charged cold cometary ions. Both detectors operated perfectly up to near closest approach (approx. 600 km) to Halley, but impacts of dust particles and neutral gas on the spacecraft contaminated parts of the data during the last few minutes. Although no flight hardware was fabricated in the U.S., The U.S. made very significant contributions to the hardware design, ground support equipment (GSE) design and fabrication, and flight and data reduction software required for the experiment, and also participated fully in the data reduction and analysis, and theoretical modeling and interpretation. Cometary data analysis is presented.
Eggleton, Kyle; Goodyear-Smith, Felicity; Henning, Marcus; Jones, Rhys; Shulruf, Boaz
2017-03-01
The aim of this study was to develop an instrument (University of Auckland General Practice Report of Educational Environment: UAGREE) with robust psychometric properties that measured the educational environment of undergraduate primary care. The questions were designed to incorporate measurements of the teaching of cultural competence. Following a structured consensus process and an initial pilot, a list of 55 questions was developed. All Year 5 and 6 students completing a primary care attachment at Auckland University were invited to complete the questionnaire. The results were analysed using exploratory factor analysis and confirmatory factor analysis resulting in a 16-item instrument. Three factors were identified explaining 53% of the variance. The items' reliability within the factors were high (Learning: 0.894; Teaching: 0.871; Cultural competence: 0.857). Multiple groups analysis by gender; and separately across ethnic groups did not find significant differences between groups. UAGREE is a specific instrument measuring the undergraduate primary care educational environment. Its questions fit within established theoretical educational environment frameworks and the incorporation of cultural competence questions reflects the importance of teaching cultural competence within medicine. The psychometric properties of UAGREE suggest that it is a reliable and valid measure of the primary care education environment.
The Safety Culture Enactment Questionnaire (SCEQ): Theoretical model and empirical validation.
de Castro, Borja López; Gracia, Francisco J; Tomás, Inés; Peiró, José M
2017-06-01
This paper presents the Safety Culture Enactment Questionnaire (SCEQ), designed to assess the degree to which safety is an enacted value in the day-to-day running of nuclear power plants (NPPs). The SCEQ is based on a theoretical safety culture model that is manifested in three fundamental components of the functioning and operation of any organization: strategic decisions, human resources practices, and daily activities and behaviors. The extent to which the importance of safety is enacted in each of these three components provides information about the pervasiveness of the safety culture in the NPP. To validate the SCEQ and the model on which it is based, two separate studies were carried out with data collection in 2008 and 2014, respectively. In Study 1, the SCEQ was administered to the employees of two Spanish NPPs (N=533) belonging to the same company. Participants in Study 2 included 598 employees from the same NPPs, who completed the SCEQ and other questionnaires measuring different safety outcomes (safety climate, safety satisfaction, job satisfaction and risky behaviors). Study 1 comprised item formulation and examination of the factorial structure and reliability of the SCEQ. Study 2 tested internal consistency and provided evidence of factorial validity, validity based on relationships with other variables, and discriminant validity between the SCEQ and safety climate. Exploratory Factor Analysis (EFA) carried out in Study 1 revealed a three-factor solution corresponding to the three components of the theoretical model. Reliability analyses showed strong internal consistency for the three scales of the SCEQ, and each of the 21 items on the questionnaire contributed to the homogeneity of its theoretically developed scale. Confirmatory Factor Analysis (CFA) carried out in Study 2 supported the internal structure of the SCEQ; internal consistency of the scales was also supported. Furthermore, the three scales of the SCEQ showed the expected correlation patterns with the measured safety outcomes. Finally, results provided evidence of discriminant validity between the SCEQ and safety climate. We conclude that the SCEQ is a valid, reliable instrument supported by a theoretical framework, and it is useful to measure the enactment of safety culture in NPPs. Copyright © 2017 Elsevier Ltd. All rights reserved.
From Theory to Application: A Study of Knowledge Transfer in Dental Education
ERIC Educational Resources Information Center
Peltz, Ivy D.
2014-01-01
Traditionally, dental education is divided into two phases: pre-clinical and clinical education. The pre-clinical phase of dental education includes the assimilation of theoretical topical knowledge in addition to the completion of simulated exercises. Upon completion of and demonstration of competency in their pre-clinical courses, students begin…
Students' perspectives on basic nursing care education.
Huisman-de Waal, Getty; Feo, Rebecca; Vermeulen, Hester; Heinen, Maud
2018-02-05
The aim of the study is to explore the perspectives of nursing students on their education concerning basic nursing care, learned either during theoretical education or clinical placement, with a specific focus on nutrition and communication. Basic care activities lie at the core of nursing, but are ill-informed by evidence and often poorly delivered. Nursing students' education on basic care might be lacking, and the question remains how they learn to deliver basic care in clinical practice. Descriptive study, using an online questionnaire. Nursing students at the vocational and bachelor level of six nursing schools in the Netherlands were invited to complete an online questionnaire regarding their perception of basic nursing care education in general (both theoretical education and clinical placement), and specifically in relation to nutrition and communication. Nursing students (n=226 bachelor students, n=30 vocational students) completed the questionnaire. Most students reported that they learned more about basic nursing care during clinical placement than during theoretical education. Vocational students also reported learning more about basic nursing care in both theoretical education and clinical practice than bachelor students. In terms of nutrition, low numbers of students from both education levels reported learning about nutrition protocols and guidelines during theoretical education. In terms of communication, vocational students indicated that they learned more about different aspects of communication during clinical practice than theoretical education, and were also more likely to learn about communication (in both theoretical education and clinical practice) than were bachelor students. Basic nursing care seems to be largely invisible in nursing education, especially at the bachelor level and during theoretical education. Improved basic nursing care will enhance nurse sensitive outcomes and patient satisfaction and will contribute to lower healthcare costs. This study shows that there is scope within current nurse education in the Netherlands to focus more systematically and explicitly on basic nursing care. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.
Toledano-Magaña, Yanis; García-Ramos, Juan Carlos; Navarro-Olivarria, Marisol; Flores-Alamo, Marcos; Manzanera-Estrada, Mayra; Ortiz-Frade, Luis; Galindo-Murillo, Rodrigo; Ruiz-Azuara, Lena; Meléndrez-Luevano, Ruth Ma; Cabrera-Vivas, Blanca M
2015-05-29
Four new hydrazones were synthesized by the condensation of the selected hydrazine and the appropriate nitrobenzaldehyde. A complete characterization was done employing 1H- and 13C-NMR, electrochemical techniques and theoretical studies. After the characterization and electrochemical analysis of each compound, amoebicidal activity was tested in vitro against the HM1:IMSS strain of Entamoeba histolytica. The results showed the influence of the nitrobenzene group and the hydrazone linkage on the amoebicidal activity. meta-Nitro substituted compound 2 presents a promising amoebicidal activity with an IC50 = 0.84 μM, which represents a 7-fold increase in cell growth inhibition potency with respect to metronidazole (IC50 = 6.3 μM). Compounds 1, 3, and 4 show decreased amoebicidal activity, with IC50 values of 7, 75 and 23 µM, respectively, as a function of the nitro group position on the aromatic ring. The observed differences in the biological activity could be explained not only by the redox potential of the molecules, but also by their capacity to participate in the formation of intra- and intermolecular hydrogen bonds. Redox potentials as well as the amoebicidal activity can be described with parameters obtained from the DFT analysis.
A theoretical analysis of steady-state photocurrents in simple silicon diodes
NASA Technical Reports Server (NTRS)
Edmonds, L.
1995-01-01
A theoretical analysis solves for the steady-state photocurrents produced by a given photo-generation rate function with negligible recombination in simple silicon diodes, consisting of a uniformly doped quasi-neutral region (called 'substrate' below) adjacent to a p-n junction depletion region (DR). Special attention is given to conditions that produce 'funneling' (a term used by the single-eventeffects community) under steady-state conditions. Funneling occurs when carriers are generated so fast that the DR becomes flooded and partially or completely collapses. Some or nearly all of the applied voltage, plus built-in potential normally across the DR, is now across the substrate. This substrate voltage drop affects substrate currents. The steady-state problem can provide some qualitative insights into the more difficult transient problem. First, it was found that funneling can be induced from a distance, i.e., from carriers generated at locations outside of the DR. Secondly, it was found that the substrate can divide into two subregions, with one controlling substrate resistance and the other characterized by ambipolar diffusion. Finally, funneling was found to be more difficult to induce in the p(sup +)/n diode than in the n(sup +)/p diode. The carrier density exceeding the doping density in the substrate and at the DR boundary is not a sufficient condition to collapse a DR.
Geier, Manfred; Arienti, Marco
2014-07-19
Increasing interest in polarimetric characterization of atmospheric aerosols has led to the development of complete sample-measuring (Mueller) polarimeters that are capable of measuring the entire backscattering phase matrix of a probed volume. The Mueller polarimeters consist of several moving parts, which limit measurement rates and complicate data analysis. In this paper, we present the concept of a less complex polarization lidar setup for detection of preferential orientation of atmospheric particulates. On the basis of theoretical considerations of data inversion stability and propagation of measurement uncertainties, an optimum optical configuration is established for two modes of operation (with either a linearmore » or a circular polarized incident laser beam). We discovered that the conceptualized setup falls in the category of incomplete sample-measuring polarimeters and uses four detection channels for simultaneous measurement of the backscattered light. Likewise, the expected performance characteristics are discussed through an example of a typical aerosol with a small fraction of particles oriented in a preferred direction. As a result, the theoretical analysis suggests that achievable accuracies in backscatter cross-sections and depolarization ratios are similar to those with conventional two-channel configurations, while in addition preferential orientation can be detected with the proposed four-channel system for a wide range of conditions.« less
Hydrodynamic Properties of Planing Surfaces and Flying Boats
NASA Technical Reports Server (NTRS)
Sokolov, N. A.
1950-01-01
The study of the hydrodynamic properties of planing bottom of flying boats and seaplane floats is at the present time based exclusively on the curves of towing tests conducted in tanks. In order to provide a rational basis for the test procedure in tanks and practical design data, a theoretical study must be made of the flow at the step and relations derived that show not only qualitatively but quantitatively the inter-relations of the various factors involved. The general solution of the problem of the development of hydrodynamic forces during the motion of the seaplane float or flying boat is very difficult for it is necessary to give a three-dimensional solution, which does not always permit reducing the analysis to the form of workable computation formulas. On the other had, the problem is complicated by the fact that the object of the analysis is concerned with two fluid mediums, namely, air and water, which have a surface of density discontinuity between them. The theoretical and experimental investigations on the hydrodynamics of a ship cannot be completely carried over to the design of floats and flying-boat hulls, because of the difference in the shape of the contour lines of the bodies, and, because of the entirely different flow conditions from the hydrodynamic viewpoint.
[Stress and attitudes toward negative emotions in adolescence].
Ozawa, Eiji
2010-12-01
This study investigated the relationship between stress and attitudes toward negative emotions in adolescents. Adolescent students (N=1500) completed a questionnaire that measured attitudes toward negative emotions, emotional-stress reactions, and stress coping. Analysis of date yielded, two factors of the attitudes toward negative emotions: "Negative feelings about negative emotions" and "Capabilities of switching of negative emotions". In order to examine the theoretical relationships among attitudes toward negative emotions, emotional-stress reactions, and stress coping, a hypothetical model was tested by covariance structure analysis. This model predicted that students who have a high level of attitudes toward negative emotions would report enhanced problem solving which promoted stress coping. The results indicated that "Negative feelings about negative emotions" enhanced avoidable coping, and avoidable coping enhanced stress reactions. "Capabilities of switching of negative emotions" was related to a decrease of avoidable coping. Based on the results from covariance structure analysis and a multiple population analysis, the clinical significance and developmental characteristics were discussed.
X-ray Variability Constraints on Compton Cloud Models of Cygnus X-1
NASA Technical Reports Server (NTRS)
Vaughan, Brian
1999-01-01
We have now completed this work, and all related publications have either appeared in print or are currently in press. A list of these publications is given below. There have been essentially three works that have arisen from this proposal. Spectral analysis of the data is presented in Dove et al. (1998a). Timing analysis is presented in Nowak et al. (1999a). Theoretical implications of the data analysis are discussed in Nowak et al. (1999b). Preliminary versions of all these works were presented at various conferences, and are reported in Nowak et al. (1997, 1998), Wilms et al. (1997), and Dove et al. (1998b). The grant was predominantly used for salary support for Dr. Michael Nowak, Dr. James Dove, and Dr. J. Wilms during the course of these projects. Grant funds were also used for Dr. Nowak to travel to Caltech to perform data analysis with Dr. Brian Vaughan, and for Dr. Wilms to visit JILA, University of Colorado, where much of this work was performed.
Hydrodynamic Characteristics of Two Low-Drag Supercavitating Hydrofoils
NASA Technical Reports Server (NTRS)
McGehee, John R.; Johnson, Virgil E., Jr.
1959-01-01
An experimental investigation has been conducted in Langley tank no. 2 to determine the hydrodynamic characteristics of two low-drag supercavitating hydrofoils operating in a range of cavitation numbers from 0 to approximately 6. The hydrofoils had aspect ratios of 1 and 3, and the sections were derived by assuming five terms in the vorticity-distribution expansion of the equivalent airfoil. The aspect-ratio-1 hydrofoil was also tested at zero cavitation number with two sets of end plates having depths of 3/8 and 1/4 chords. Zero cavitation number was established by operating the hydrofoils near the water surface so that complete ventilation of the upper surfaces could be obtained. For those depths of submersion where complete ventilation was not obtained through vortex ventilation, two probes were used to introduce air to the upper surfaces of the hydrofoils and to induce complete ventilation. Data were obtained for a range of speeds from 20 to 80 fps, angles of attack from 2 to 20 deg, and ratios of depth of submersion to chord from 0 to 0.85. The experimental results obtained from the aspect-ratio-1 and aspect-ratio-3, five-term hydrofoils were compared with a three-dimensional zero-cavitation-number theory. The theoretical and experimental values of lift and center of pressure for the aspect-ratio-1 hydrofoil were in agreement, within engineering accuracy, for the range of lift coefficients investigated. The theoretical drag coefficients were lower, by a constant amount, than the experimental drag coefficients. The theoretical expressions derived for the lift, drag, and center of pressure of the aspect-ratio-3 hydrofoil were in agreement, within engineering accuracy, with the experimental values. The theoretical and experimental drag coefficients of the aspect-ratio-3 five-term hydrofoil were lower than the theoretical drag coefficients computed for a comparable Tulin-Burkart hydrofoil.
Yuan, Weihong; Treble-Barna, Amery; Sohlberg, McKay M; Harn, Beth; Wade, Shari L
2017-02-01
Structural connectivity analysis based on graph theory and diffusion tensor imaging tractography is a novel method that quantifies the topological characteristics in the brain network. This study aimed to examine structural connectivity changes following the Attention Intervention and Management (AIM) program designed to improve attention and executive function (EF) in children with traumatic brain injury (TBI). Seventeen children with complicated mild to severe TBI (13.66 ± 2.68 years; >12 months postinjury) completed magnetic resonance imaging (MRI) and neurobehavioral measures at time 1, 10 of whom completed AIM and assessment at time 2. Eleven matched healthy comparison (HC) children (13.37 ± 2.08 years) completed MRI and neurobehavioral assessment at both time points, but did not complete AIM. Network characteristics were analyzed to quantify the structural connectivity before and after the intervention. Mixed model analyses showed that small-worldness was significantly higher in the TBI group than the HC group at time 1, and both small-worldness and normalized clustering coefficient decreased significantly at time 2 in the TBI group whereas the HC group remained relatively unchanged. Reductions in mean local efficiency were significantly correlated with improvements in verbal inhibition and both parent- and child-reported EF. Increased normalized characteristic path length was significantly correlated with improved sustained attention. The results provide preliminary evidence suggesting that graph theoretical analysis may be a sensitive tool in pediatric TBI for detecting ( a) abnormalities of structural connectivity in brain network and ( b) structural neuroplasticity associated with neurobehavioral improvement following a short-term intervention for attention and EF.
NASA Astrophysics Data System (ADS)
Ünal, A.; Okur, M.
2017-02-01
The possible four stable rotational isomers of 4-phenylbutylamine (4PBA) molecule were experimentally and theoretically studied by vibrational spectroscopy. The FT-IR (4000-400 cm-1) and Raman (3700-60 cm-1) spectra of 4PBA were recorded at room temperature in liquid phase. The complete vibrational wavenumbers and corresponding vibrational assignments of 4PBA molecule were discussed assisted with B3LYP/6-311++G(d,p) level of theory along with scaled quantum mechanics force field (SQM-FF) method. Results from experimental and theoretical data the most stable form of 4PBA molecule was obtained.
A Monte Carlo investigation of thrust imbalance of solid rocket motor pairs
NASA Technical Reports Server (NTRS)
Sforzini, R. H.; Foster, W. A., Jr.; Johnson, J. S., Jr.
1974-01-01
A technique is described for theoretical, statistical evaluation of the thrust imbalance of pairs of solid-propellant rocket motors (SRMs) firing in parallel. Sets of the significant variables, determined as a part of the research, are selected using a random sampling technique and the imbalance calculated for a large number of motor pairs. The performance model is upgraded to include the effects of statistical variations in the ovality and alignment of the motor case and mandrel. Effects of cross-correlations of variables are minimized by selecting for the most part completely independent input variables, over forty in number. The imbalance is evaluated in terms of six time - varying parameters as well as eleven single valued ones which themselves are subject to statistical analysis. A sample study of the thrust imbalance of 50 pairs of 146 in. dia. SRMs of the type to be used on the space shuttle is presented. The FORTRAN IV computer program of the analysis and complete instructions for its use are included. Performance computation time for one pair of SRMs is approximately 35 seconds on the IBM 370/155 using the FORTRAN H compiler.
Doyle, Frank; McGee, Hannah; Delaney, Mary; Motterlini, Nicola; Conroy, Ronán
2011-01-01
Depression is prevalent in patients hospitalized with acute coronary syndrome (ACS). We determined whether theoretical vulnerabilities for depression (interpersonal life events, reinforcing events, cognitive distortions, Type D personality) predicted depression, or depression trajectories, post-hospitalization. We followed 375 ACS patients who completed depression scales during hospital admission and at least once during three follow-up intervals over 1 year (949 observations). Questionnaires assessing vulnerabilities were completed at baseline. Logistic regression for panel/longitudinal data predicted depression status during follow-up. Latent class analysis determined depression trajectories. Multinomial logistic regression modeled the relationship between vulnerabilities and trajectories. Vulnerabilities predicted depression status over time in univariate and multivariate analysis, even when controlling for baseline depression. Proportions in each depression trajectory category were as follows: persistent (15%), subthreshold (37%), never depressed (48%). Vulnerabilities independently predicted each of these trajectories, with effect sizes significantly highest for the persistent depression group. Self-reported vulnerabilities - stressful life events, reduced reinforcing events, cognitive distortions, personality - measured during hospitalization can identify those at risk for depression post-ACS and especially those with persistent depressive episodes. Interventions should focus on these vulnerabilities. Copyright © 2011 Elsevier Inc. All rights reserved.
High Performance Parallel Analysis of Coupled Problems for Aircraft Propulsion
NASA Technical Reports Server (NTRS)
Felippa, C. A.; Farhat, C.; Lanteri, S.; Maman, N.; Piperno, S.; Gumaste, U.
1994-01-01
In order to predict the dynamic response of a flexible structure in a fluid flow, the equations of motion of the structure and the fluid must be solved simultaneously. In this paper, we present several partitioned procedures for time-integrating this focus coupled problem and discuss their merits in terms of accuracy, stability, heterogeneous computing, I/O transfers, subcycling, and parallel processing. All theoretical results are derived for a one-dimensional piston model problem with a compressible flow, because the complete three-dimensional aeroelastic problem is difficult to analyze mathematically. However, the insight gained from the analysis of the coupled piston problem and the conclusions drawn from its numerical investigation are confirmed with the numerical simulation of the two-dimensional transient aeroelastic response of a flexible panel in a transonic nonlinear Euler flow regime.
Schmitt, J F; Meline, T J
1990-12-01
We reviewed the 1983-1988 issues of six journals that frequently publish papers including specifically language-impaired (LI) subjects. A total of 92 research reports provided data for our review. The research reports included experimental studies, ex post facto studies, and intervention studies. These studies represent a broad spectrum of the theoretical and empirical foundations of knowledge regarding LI children. The analysis of the published research centered on subject descriptions and the use of control groups. A descriptive analysis of the data showed few consistent trends among the studies with respect to subject selection, subject description, and the number and types of control groups. We discuss the importance of more complete subject descriptions in studies of LI children as well as the importance of the choice of matching criteria for control groups in between-subjects designs.
Research on the strategy of underwater united detection fusion and communication using multi-sensor
NASA Astrophysics Data System (ADS)
Xu, Zhenhua; Huang, Jianguo; Huang, Hai; Zhang, Qunfei
2011-09-01
In order to solve the distributed detection fusion problem of underwater target detection, when the signal to noise ratio (SNR) of the acoustic channel is low, a new strategy for united detection fusion and communication using multiple sensors was proposed. The performance of detection fusion was studied and compared based on the Neyman-Pearson principle when the binary phase shift keying (BPSK) and on-off keying (OOK) modes were used by the local sensors. The comparative simulation and analysis between the optimal likelihood ratio test and the proposed strategy was completed, and both the theoretical analysis and simulation indicate that using the proposed new strategy could improve the detection performance effectively. In theory, the proposed strategy of united detection fusion and communication is of great significance to the establishment of an underwater target detection system.
ERIC Educational Resources Information Center
Lott, Donalyn; O'Dell, Jade
2014-01-01
This study examined the efficacy of general education development (GED®) acquisition and GED® completers' perceptions of college readiness and social capital using a quantitative methodology. Also, the study used a descriptive, cross-sectional research design framed by the social capital theoretical perspective. The conceptual framework developed…
Mapping the organizational culture research in nursing: a literature review.
Scott-Findlay, Shannon; Estabrooks, Carole A
2006-12-01
This paper reports a critical review of nursing organizational culture research studies with the objectives of: (1) reviewing theoretical and methodological characteristics of the studies and (2) drawing inferences specific to the state of knowledge in this field. Organizational culture is regarded as significant in influencing research use in clinical practice yet it is not understood how culture shapes practitioners' behaviours. Only one review of this empirical literature in nursing has been completed. Using selected computerized databases, published nursing research studies in English that examine organizational culture were accessed. Organizational culture studies were categorized using Hatch's three perspectives on organizational culture: (1) modern, (2) symbolic-interpretive and (3) postmodern. The review was conducted in 2005. Twenty-nine studies were in the final data set. Results pointed to variations in cultural definitions and incorporation of organizational sciences theory. In classifying the studies, modern perspectives dominated (n = 22), symbolic-interpretive approaches were an emerging group (n = 6) and one study was unclassifiable. Our results expand current cultural instrument reviews by pinpointing tools that have been previously overlooked and by identifying ongoing theoretical and methodological challenges for researchers. An exclusive reliance on modernistic approaches in organizational culture research cannot yield a complete understanding of the phenomenon. Rather, the field could benefit from a variety of cultural approaches. In a similar vein, researchers need to be mindful of the terminology and the unit of analysis they use in their research, as these are the two largest research challenges.
Theoretical Dipole Moment for the X211 State of NO
NASA Technical Reports Server (NTRS)
Langhoff, Stephen R.; Bauschlicher, Charles W., Jr.; Partridge, Harry; Arnold, James O. (Technical Monitor)
1994-01-01
The dipole moment function for the X(sup 2)II state of NO is studied as a function of the completeness in both the one- and n-particle spaces. Einstein coefficients are presented that are significantly more accurate than previous tabulations for the higher vibrational levels. The theoretical values give considerable insight into the limitations of recently published ratios of Einstein coefficients measured by spectrally resolved infrared chemiluminescence.
1990-12-01
process; (4) the degree efbudgetary responsiveness in DOD/DON cutback budgeting to criteria developed from two theoretical models of fical reduction... developed from two theoretical models of fiscal reduction methodology. |V ..... A A,’ 4 . 0 f .; . . Dis Apm a al@r Di3t I peala iii, TARLK Or COUTENS...accompanying reshaping of U.S. forces include a continuation of the positive developments in Eastern Europe and the Soviet Union, completion of
ERIC Educational Resources Information Center
Benesh, Andrew Christopher
2017-01-01
Purpose: The purpose of this study was to fill a gap in the literature by examining the relationship between dogmatism, locus of control, counselor self-efficacy, and counselor theoretical orientation in a sample of master's level practicum students. Method: A total of 45 master's practicum students completed a series of four instruments, the DOG…
Villafranca, Alexander; Hamlin, Colin; Rodebaugh, Thomas L; Robinson, Sandra; Jacobsohn, Eric
2017-09-10
Disruptive intraoperative behavior has detrimental effects to clinicians, institutions, and patients. How clinicians respond to this behavior can either exacerbate or attenuate its effects. Previous investigations of disruptive behavior have used survey scales with significant limitations. The study objective was to develop appropriate scales to measure exposure and responses to disruptive behavior. We obtained ethics approval. The scales were developed in a sequence of steps. They were pretested using expert reviews, computational linguistic analysis, and cognitive interviews. The scales were then piloted on Canadian operating room clinicians. Factor analysis was applied to half of the data set for question reduction and grouping. Item response analysis and theoretical reviews ensured that important questions were not eliminated. Internal consistency was evaluated using Cronbach α. Model fit was examined on the second half of the data set using confirmatory factor analysis. Content validity of the final scales was re-evaluated. Consistency between observed relationships and theoretical predictions was assessed. Temporal stability was evaluated on a subsample of 38 respondents. A total of 1433 and 746 clinicians completed the exposure and response scales, respectively. Content validity indices were excellent (exposure = 0.96, responses = 1.0). Internal consistency was good (exposure = 0.93, responses = 0.87). Correlations between the exposure scale and secondary measures were consistent with expectations based on theory. Temporal stability was acceptable (exposure = 0.77, responses = 0.73). We have developed scales measuring exposure and responses to disruptive behavior. They generate valid and reliable scores when surveying operating room clinicians, and they overcome the limitations of previous tools. These survey scales are freely available.
NASA Astrophysics Data System (ADS)
Demircioğlu, Zeynep; Yeşil, Ahmet Emin; Altun, Mehmet; Bal-Demirci, Tülay; Özdemir, Namık
2018-06-01
The compound 4‧-(2,4-dimethoxyphenyl)-2,2‧:6‧,2″-terpyridine (Mtpyr) was synthesized and investigated using X-ray single crystal structure determination, combined with Hirshfeld topology analysis of the molecular packing. In addition, Mtpyr was characterized by experimental and theoretical FT-IR, UV-Vis, 1H NMR, 13C NMR and fluorescence emission spectra. The optimized molecular geometry (bond length, bond angle, torsion angle), the complete vibrational frequency and all other theoretical computations were calculated by using density functional theory (DFT) B3LYP method with the help of 6-311++G(d,p) basis set. From the recorded UV-Vis spectrum, the electronic properties such as excitation energies, wavelength and oscillator strength are evaluated by TD-DFT in chloroform solution. The 1H and 13C nuclear magnetic resonance (NMR) chemical shifts of the molecule were calculated by the gauge-independent atomic orbital (GIAO) method and compared with experimental results. The calculated HOMO-LUMO band gap energies confirmed that charge transfer and chemical stability within the molecule. The hyperconjugative interaction energy E(2) and electron densities of donor (i) and acceptor (j) bonds were calculated using natural bond orbital (NBO) analysis. Besides Mulliken and natural population charges (NPA), non-linear optic properties (NLO), Fukui Function analysis, molecular electrostatic potential (MEP) were also computed which helps to identifying the electrophilic/nucleophilic nature.
Ernst, Marielle; Kriston, Levente; Romero, Javier M.; Frölich, Andreas M.; Jansen, Olav; Fiehler, Jens; Buhk, Jan-Hendrik
2016-01-01
Purpose We sought to develop a standardized curriculum capable of assessing key competencies in Interventional Neuroradiology by the use of models and simulators in an objective, quantitative, and efficient way. In this evaluation we analyzed the associations between the practical experience, theoretical knowledge, and the skills lab performance of interventionalists. Materials and Methods We evaluated the endovascular skills of 26 participants of the Advanced Course in Endovascular Interventional Neuroradiology of the European Society of Neuroradiology with a set of three tasks (aneurysm coiling and thrombectomy in a virtual simulator and placement of an intra-aneurysmal flow disruptor in a flow model). Practical experience was assessed by a survey. Participants completed a written and oral examination to evaluate theoretical knowledge. Bivariate and multivariate analyses were performed. Results In multivariate analysis knowledge of materials and techniques in Interventional Neuroradiology was moderately associated with skills in aneurysm coiling and thrombectomy. Experience in mechanical thrombectomy was moderately associated with thrombectomy skills, while age was negatively associated with thrombectomy skills. We found no significant association between age, sex, or work experience and skills in aneurysm coiling. Conclusion Our study gives an example of how an integrated curriculum for reasonable and cost-effective assessment of key competences of an interventional neuroradiologist could look. In addition to traditional assessment of theoretical knowledge practical skills are measured by the use of endovascular simulators yielding objective, quantitative, and constructive data for the evaluation of the current performance status of participants as well as the evolution of their technical competency over time. PMID:26848840
The Necessity of Functional Analysis for Space Exploration Programs
NASA Technical Reports Server (NTRS)
Morris, A. Terry; Breidenthal, Julian C.
2011-01-01
As NASA moves toward expanded commercial spaceflight within its human exploration capability, there is increased emphasis on how to allocate responsibilities between government and commercial organizations to achieve coordinated program objectives. The practice of program-level functional analysis offers an opportunity for improved understanding of collaborative functions among heterogeneous partners. Functional analysis is contrasted with the physical analysis more commonly done at the program level, and is shown to provide theoretical performance, risk, and safety advantages beneficial to a government-commercial partnership. Performance advantages include faster convergence to acceptable system solutions; discovery of superior solutions with higher commonality, greater simplicity and greater parallelism by substituting functional for physical redundancy to achieve robustness and safety goals; and greater organizational cohesion around program objectives. Risk advantages include avoidance of rework by revelation of some kinds of architectural and contractual mismatches before systems are specified, designed, constructed, or integrated; avoidance of cost and schedule growth by more complete and precise specifications of cost and schedule estimates; and higher likelihood of successful integration on the first try. Safety advantages include effective delineation of must-work and must-not-work functions for integrated hazard analysis, the ability to formally demonstrate completeness of safety analyses, and provably correct logic for certification of flight readiness. The key mechanism for realizing these benefits is the development of an inter-functional architecture at the program level, which reveals relationships between top-level system requirements that would otherwise be invisible using only a physical architecture. This paper describes the advantages and pitfalls of functional analysis as a means of coordinating the actions of large heterogeneous organizations for space exploration programs.
NASA Astrophysics Data System (ADS)
Anoukou, K.; Pastor, F.; Dufrenoy, P.; Kondo, D.
2016-06-01
The present two-part study aims at investigating the specific effects of Mohr-Coulomb matrix on the strength of ductile porous materials by using a kinematic limit analysis approach. While in the Part II, static and kinematic bounds are numerically derived and used for validation purpose, the present Part I focuses on the theoretical formulation of a macroscopic strength criterion for porous Mohr-Coulomb materials. To this end, we consider a hollow sphere model with a rigid perfectly plastic Mohr-Coulomb matrix, subjected to axisymmetric uniform strain rate boundary conditions. Taking advantage of an appropriate family of three-parameter trial velocity fields accounting for the specific plastic deformation mechanisms of the Mohr-Coulomb matrix, we then provide a solution of the constrained minimization problem required for the determination of the macroscopic dissipation function. The macroscopic strength criterion is then obtained by means of the Lagrangian method combined with Karush-Kuhn-Tucker conditions. After a careful analysis and discussion of the plastic admissibility condition associated to the Mohr-Coulomb criterion, the above procedure leads to a parametric closed-form expression of the macroscopic strength criterion. The latter explicitly shows a dependence on the three stress invariants. In the special case of a friction angle equal to zero, the established criterion reduced to recently available results for porous Tresca materials. Finally, both effects of matrix friction angle and porosity are briefly illustrated and, for completeness, the macroscopic plastic flow rule and the voids evolution law are fully furnished.
Zheng, Yangyang; Yuan, Qianqian; Yang, Xiaoyan; Ma, Hongwu
2017-11-01
Poly-(3-hydroxybutyrate) (P3HB) is a promising biodegradable plastic synthesized from acetyl-CoA. One important factor affecting the P3HB production cost is the P3HB yield. Through flux balance analysis of an extended genome-scale metabolic network of E. coli, we found that the introduction of non-oxidative glycolysis pathway (NOG), a previously reported pathway enabling complete carbon conservation, can increase the theoretical carbon yield from 67% to 89%, equivalent to the theoretical mass yield from 0.48g P3HB/g glucose to 0.64g P3HB/g glucose. Based on this analysis result, we introduced phosphoketolase and enhanced the NOG pathway in E. coli. The mass yield in the engineered strain was increased from 0.16g P3HB/g glucose to 0.24g P3HB/g glucose. We further overexpressed pntAB to enhance the NADPH availability and down-regulated TCA cycle to divert more acetyl-CoA toward P3HB. The final construct accumulated 5.7g/L P3HB and reached a carbon yield of 0.43 (a mass yield of 0.31g P3HB/g glucose) in shake flask cultures in shake flask cultures. The introduction of NOG pathway could also be useful for improving yields of many other biochemicals derived from acetyl-coA. Copyright © 2017 Elsevier Inc. All rights reserved.
Health hybrid concept analysis in old people.
Asadi Noughabi, Ahmadali; Alhani, Fatemeh; Piravi, Hamid
2013-10-31
It seems necessary to study the health status of this age group to promote their health and prevent disease as well as care planning. In order to achieve this goal, a clear definition of the concept of elderly health is essential. Hybrid concept analysis, our research design, utilizes both theoretical analysis of literature and empirical observation to define a concept. We chose the hybrid concept analysis method because its inclusion of old people perspectives enriches the limited health research literature. The method consists of three phases: theory, fieldwork, and analysis. In comparison, we can conclude that health in the elderly people is something more than the absence of illness and 4 physical, mental, social and spiritual domains which are referred to in the definition of a theoretical stage are supported by the findings. The relative health was also proposed against the complete welfare and comfort for the elderly and it showed that their expectations are less than their ages. In addition, the elderly have expressed the family as a preference and the researcher believes that this theme is context based because it has emerged following the interview. Since the family has a special place according to the Iranian culture and religion and the family health is a priority in their health. In addition, the daily activities have been raised as a major theme that can be considered as the physical health but the elderly have expressed it apart from the physical health. Health among the old is a concept that is affected by genetic, environmental, healthcare services and lifestyle-related factors and involves proportional physical, mental, social, familial, spiritual, and economical welfare along with the ability to handle daily life activities which is measurable through medical and functional approaches.
A tutorial on the use of ROC analysis for computer-aided diagnostic systems.
Scheipers, Ulrich; Perrey, Christian; Siebers, Stefan; Hansen, Christian; Ermert, Helmut
2005-07-01
The application of the receiver operating characteristic (ROC) curve for computer-aided diagnostic systems is reviewed. A statistical framework is presented and different methods of evaluating the classification performance of computer-aided diagnostic systems, and, in particular, systems for ultrasonic tissue characterization, are derived. Most classifiers that are used today are dependent on a separation threshold, which can be chosen freely in many cases. The separation threshold separates the range of output values of the classification system into different target groups, thus conducting the actual classification process. In the first part of this paper, threshold specific performance measures, e.g., sensitivity and specificity, are presented. In the second part, a threshold-independent performance measure, the area under the ROC curve, is reviewed. Only the use of separation threshold-independent performance measures provides classification results that are overall representative for computer-aided diagnostic systems. The following text was motivated by the lack of a complete and definite discussion of the underlying subject in available textbooks, references and publications. Most manuscripts published so far address the theme of performance evaluation using ROC analysis in a manner too general to be practical for everyday use in the development of computer-aided diagnostic systems. Nowadays, the user of computer-aided diagnostic systems typically handles huge amounts of numerical data, not always distributed normally. Many assumptions made in more or less theoretical works on ROC analysis are no longer valid for real-life data. The paper aims at closing the gap between theoretical works and real-life data. The review provides the interested scientist with information needed to conduct ROC analysis and to integrate algorithms performing ROC analysis into classification systems while understanding the basic principles of classification.
Health Hybrid Concept Analysis in Old People
Noghabi, Ahamadali Asadi; Alhani, Fatemeh; Peyrovi, Hamid
2013-01-01
Background: It seems necessary to study the health status of this age group to promote their health and prevent disease as well as care planning. In order to achieve this goal, a clear definition of the concept of elderly health is essential. Method: Hybrid concept analysis, our research design, utilizes both theoretical analysis of literature and empirical observation to define a concept. We chose the hybrid concept analysis method because its inclusion of old people perspectives enriches the limited health research literature. The method consists of three phases theory, fieldwork, and analysis. Results: In comparison, we can conclude that health in the elderly people is something more than the absence of illness and 4 physical, mental, social and spiritual domains which are referred to in the definition of a theoretical stage are supported by the findings. The relative health was also proposed against the complete welfare and comfort for the elderly and it showed that their expectations are less than their ages. In addition, the elderly have expressed the family as a preference and the researcher believes that this theme is context based because it has emerged following the interview. Since the family has a special place according to the Iranian culture and religion and the family health is a priority in their health. In addition, the daily activities have been raised as a major theme that can be considered as the physical health but the elderly have expressed it apart from the physical health. Conclusion: Health among the old is a concept that is affected by genetic, environmental, healthcare services and lifestyle-related factors and involves proportional physical, mental, social, familial, spiritual, and economical welfare along with the ability to handle daily life activities which is measurable through medical and functional approaches. PMID:24171892
State of the science of maternal-infant bonding: a principle-based concept analysis.
Bicking Kinsey, Cara; Hupcey, Judith E
2013-12-01
to provide a principle-based analysis of the concept of maternal-infant bonding. principle-based method of concept analysis for which the data set included 44 articles published in the last decade from Pubmed, CINAHL, and PyschINFO/PsychARTICLES. literature inclusion criteria were English language, articles published in the last decade, peer-reviewed journal articles and commentary on published work, and human populations. after a brief review of the history of maternal-infant bonding, a principle-based concept analysis was completed to examine the state of the science with regard to this concept. The concept was critically examined according to the clarity of definition (epistemological principle), applicability of the concept (pragmatic principle), consistency in use and meaning (linguistic principle), and differentiation of the concept from related concepts (logical principle). Analysis of the concept revealed: (1) Maternal-infant bonding describes maternal feelings and emotions towards her infant. Evidence that the concept encompasses behavioural or biological components was limited. (2) The concept is clearly operationalised in the affective domain. (3) Maternal-infant bonding is linguistically confused with attachment, although the boundaries between the concepts are clearly delineated. despite widespread use of the concept, maternal-infant bonding is at times superficially developed and subject to confusion with related concepts. Concept clarification is warranted. A theoretical definition of the concept of maternal-infant bonding was developed to aid in the clarification, but more research is necessary to further clarify and advance the concept. nurse midwives and other practitioners should use the theoretical definition of maternal-infant bonding as a preliminary guide to identification and understanding of the concept in clinical practice. Copyright © 2013 Elsevier Ltd. All rights reserved.
STATE OF THE SCIENCE OF MATERNAL-INFANT BONDING: A PRINCIPLE-BASED CONCEPT ANALYSIS
Bicking Kinsey, Cara; Hupcey, Judith E.
2013-01-01
Objective To provide a principle-based analysis of the concept of maternal-infant bonding. Design Principle-based method of concept analysis for which the data set included 44 articles published in the last decade from Pubmed, CINAHL, and PyschINFO/PsychARTICLES. Setting Literature inclusion criteria were English language, articles published in the last decade, peer-reviewed journal articles and commentary on published work, and human populations. Measurement and Findings After brief review of the history of maternal-infant bonding, a principle-based concept analysis was completed to examine the state of the science with regard to this concept. The concept was critically examined according to the clarity of definition (epistemological principle), applicability of the concept (pragmatic principle), consistency in use and meaning (linguistic principle), and differentiation of the concept from related concepts (logical principle). Analysis of the concept revealed: (1) maternal-infant bonding describes maternal feelings and emotions towards her infant. Evidence that the concept encompasses behavioral or biological components was limited; (2) the concept is clearly operationalized in the affective domain; and (3) maternal-infant bonding is linguistically confused with attachment, although the boundaries between the concepts are clearly delineated. Key Conclusion Despite widespread use of the concept, maternal-infant bonding is at times superficially developed and subject to confusion with related concepts. Concept clarification is warranted. A theoretical definition of the concept of maternal-infant bonding was developed to aid in the clarification, but more research is necessary to further clarify and advance the concept. Implications for Practice Nurse midwives and other practitioners should use the theoretical definition of maternal-infant bonding as a preliminary guide to identification and understanding of the concept in clinical practice. PMID:23452661
NASA Astrophysics Data System (ADS)
Issaoui, N.; Ghalla, H.; Bardak, F.; Karabacak, M.; Aouled Dlala, N.; Flakus, H. T.; Oujia, B.
2017-02-01
In this work, the molecular structures and vibrational spectral analyses of 3-(2-Theinyl)acrylic acid (3-2TAA) monomer and dimer structures have been reported by using density functional theory calculations at B3LYP/6-311++G(d,p) level of theory. The complete assignments of the fundamental vibrational modes were obtained using potential energy distribution. Intermolecular interactions were analyzed by orbital NBO and topological AIM approaches. The electronic properties have been carried out using TD-DFT approach. Great agreements between experimental and theoretical values were achieved throughout the analysis of structural parameters and spectroscopic features. Inhibitor characteristics on human monoamine oxidase B (MAOB) enzyme of two determined stable conformers of 3-2TAA (β and γ) along with four selective inhibitors, namely safinamide, a coumarin analogue, farnesol, and phenyethylhydrazine were investigated via molecular docking. Moreover, molecular electrostatic potential (MEP) and temperature dependency of thermodynamic functions have been reported.
Wu, Kaimin; Huang, Yongjun; Wanghuang, Tenglong; Chen, Weijian; Wen, Guangjun
2015-01-10
In this paper, we numerically and theoretically discuss the novel absorption properties of a conventional metasurface-based terahertz (THz) electromagnetic (EM) absorber with different dielectric thicknesses. Two absorption modes are presented in the considered frequency band due to the increased dielectric thickness, and both modes can achieve near-unity absorptions when the dielectric layers reach additional nλ(d)/2 (n=1, 2) thicknesses, where λ(d) is the operating wavelength at the peak absorption in the dielectric slabs. The surface currents between the metasurface resonators and ground plane are not associated any longer, different from the conventional thin absorbers. Moreover, the EM wave energies are completely absorbed by the metasurface resonators and dielectric layer, and the main function of ground plane is to reflect the incident EM waves back to the resonators. The discussed novel absorption properties are analyzed and explained by classical EM theory and interference theory after numerical demonstrations. These findings can broaden the potential applications of the metasurface-based absorbers in the THz frequency range for different requirements.
NASA Astrophysics Data System (ADS)
Deandrea, A.; Gatto, R.; Ladisa, M.; Nardulli, G.; Santorelli, P.
2000-12-01
We reconsider two classical proposals for the determination of the angle γ of the unitarity triangle: B+/--->χc0π+/--->π+π-π+/- and Bs-->ρ0KS-->π+π-KS. We point out the relevance, in both cases, of nonresonant amplitudes, where the π+π- pair is produced by weak decay of a B* (JP=1-) or B0 (JP=0+) off-shell meson. In particular, for the B decay channel, the inclusion of the B0 pole completes some previous analyses and confirms their conclusions, provided a suitable cut in the Dalitz plot is performed; for the Bs decay the inclusion of the B*, B0 amplitudes enhances the role of the tree diagrams as compared to penguin amplitudes, which makes the theoretical uncertainty related to the Bs-->ρ0KS decay process less significant. While the first method is affected by theoretical uncertainties, the second one is cleaner, but its usefulness will depend on the available number of events to perform the analysis.
Diaz, Carlos; Lin, Na; Toro, Carlos; Passier, Remy; Rizzo, Antonio; Hernández, Florencio E
2012-07-05
Herein we report on the theoretical-experimental study of the effect of curvature of the π-electron delocalization on the two-photon circular dichroism (TPCD) of a family of optically active biaryl derivatives (S-BINOL, S-VANOL, and S-VAPOL). The comparative analysis of the influence of the different transition moments to their corresponding TPCD rotatory strength reveals an enhanced contribution of the magnetic transition dipole moment on VAPOL. This effect is hereby attributed to the additional twist in the π-electron delocalization on this compound. TPCD measurements were done using the double L-scan technique in the picosecond regime. Theoretical calculations were completed using modern analytical response theory, within a time-dependent density functional theory (TD-DFT) approach, at both, B3LYP and CAM-B3LYP levels, with the aug-cc-pVDZ basis set for S-BINOL and S-VANOL, and 6-31G* for S-VAPOL. Solvent effects were included by means of the polarizable continuum model (PCM) in CH2Cl2.
NASA Astrophysics Data System (ADS)
Yamada, Keisuke
2017-01-01
This paper describes passive technique for suppressing vibration in flexible structures using a multi-layered piezoelectric element, an inductor, and a resistor. The objective of using a multi-layered piezoelectric element is to increase its capacitance. A piezoelectric element with a large capacitance value does not require an active electrical circuit to simulate an inductor with a large inductance value. The effect of multi-layering of piezoelectric elements was theoretically analyzed through an equivalent transformation of a multi-layered piezoelectric element into a single-layered piezoelectric element. The governing equations were derived using this equivalent transformation. The effect of the resistances of the inductor and piezoelectric elements were considered because the sum of these resistances may exceed the optimum resistance. The performance of the passive vibration suppression using an LR circuit was compared to that of the method where a resistive circuit is used assuming that the sum of the resistances of the inductor and piezoelectric elements exceeds the optimum resistance. The effectiveness of the proposed method and theoretical analysis was verified through simulations and experiments.
Altan, Irem; Charbonneau, Patrick; Snell, Edward H.
2016-01-01
Crystallization is a key step in macromolecular structure determination by crystallography. While a robust theoretical treatment of the process is available, due to the complexity of the system, the experimental process is still largely one of trial and error. In this article, efforts in the field are discussed together with a theoretical underpinning using a solubility phase diagram. Prior knowledge has been used to develop tools that computationally predict the crystallization outcome and define mutational approaches that enhance the likelihood of crystallization. For the most part these tools are based on binary outcomes (crystal or no crystal), and the full information contained in an assembly of crystallization screening experiments is lost. The potential of this additional information is illustrated by examples where new biological knowledge can be obtained and where a target can be sub-categorized to predict which class of reagents provides the crystallization driving force. Computational analysis of crystallization requires complete and correctly formatted data. While massive crystallization screening efforts are under way, the data available from many of these studies are sparse. The potential for this data and the steps needed to realize this potential are discussed. PMID:26792536
NASA Technical Reports Server (NTRS)
Bodley, C. S.; Devers, D. A.; Park, C. A.
1975-01-01
A theoretical development and associated digital computer program system is presented. The dynamic system (spacecraft) is modeled as an assembly of rigid and/or flexible bodies not necessarily in a topological tree configuration. The computer program system may be used to investigate total system dynamic characteristics including interaction effects between rigid and/or flexible bodies, control systems, and a wide range of environmental loadings. Additionally, the program system may be used for design of attitude control systems and for evaluation of total dynamic system performance including time domain response and frequency domain stability analyses. Volume 1 presents the theoretical developments including a description of the physical system, the equations of dynamic equilibrium, discussion of kinematics and system topology, a complete treatment of momentum wheel coupling, and a discussion of gravity gradient and environmental effects. Volume 2, is a program users' guide and includes a description of the overall digital program code, individual subroutines and a description of required program input and generated program output. Volume 3 presents the results of selected demonstration problems that illustrate all program system capabilities.
A Game-Theoretical Model to Improve Process Plant Protection from Terrorist Attacks.
Zhang, Laobing; Reniers, Genserik
2016-12-01
The New York City 9/11 terrorist attacks urged people from academia as well as from industry to pay more attention to operational security research. The required focus in this type of research is human intention. Unlike safety-related accidents, security-related accidents have a deliberate nature, and one has to face intelligent adversaries with characteristics that traditional probabilistic risk assessment techniques are not capable of dealing with. In recent years, the mathematical tool of game theory, being capable to handle intelligent players, has been used in a variety of ways in terrorism risk assessment. In this article, we analyze the general intrusion detection system in process plants, and propose a game-theoretical model for security management in such plants. Players in our model are assumed to be rational and they play the game with complete information. Both the pure strategy and the mixed strategy solutions are explored and explained. We illustrate our model by an illustrative case, and find that in our case, no pure strategy but, instead, a mixed strategy Nash equilibrium exists. © 2016 Society for Risk Analysis.
Stamp, Anne Schinkel; Pedersen, Lise Lang; Ingwersen, Kim Gordon; Sørensen, Dorthe
2018-05-01
In this study we aimed to develop a theoretical account of the experienced benefit of psychomotor therapy in addition to treatment as usual in patients with chronic shoulder pain. The qualitative study design was based on a grounded theory approach. Open-ended face-to-face interviews were conducted after treatment was completed. We generated data and performed analyses by constant comparative analysis and theoretical sampling that focused on the patients' behavioural characteristics related to the experienced benefit of psychomotor therapy. We conducted 12 interviews, eight of which were with men. "Regaining capability" emerged as representative of the pattern of behaviour. Through this pattern, the patients resolved concern about losing capability. Regaining capability involved three behavioural typologies: taking advice, minding the body, and encompassing life changes. The patients' behavioural typologies revealed different levels of life changes. Psychomotor therapy offered the patients in our study new and better ways of coping with their shoulder pain. Copyright © 2018 Department of Physio- and Occupational Therapy, Hospital Lillebaelt - Vejle Hospital. Published by Elsevier Ltd.. All rights reserved.
21 CFR 211.188 - Batch production and control records.
Code of Federal Regulations, 2010 CFR
2010-04-01
... (CONTINUED) DRUGS: GENERAL CURRENT GOOD MANUFACTURING PRACTICE FOR FINISHED PHARMACEUTICALS Records and... percentage of theoretical yield at appropriate phases of processing; (8) Complete labeling control records...
21 CFR 211.188 - Batch production and control records.
Code of Federal Regulations, 2011 CFR
2011-04-01
... (CONTINUED) DRUGS: GENERAL CURRENT GOOD MANUFACTURING PRACTICE FOR FINISHED PHARMACEUTICALS Records and... percentage of theoretical yield at appropriate phases of processing; (8) Complete labeling control records...
Shiroff, Jennifer J; Gregoski, Mathew J
2017-06-01
Measurement of recessive carrier screening attitudes related to conception and pregnancy is necessary to determine current acceptance, and whether behavioral intervention strategies are needed in clinical practice. To evaluate quantitative survey instruments to measure patient attitudes regarding genetic carrier testing prior to conception and pregnancy databases examining patient attitudes regarding genetic screening prior to conception and pregnancy from 2003-2013 were searched yielding 344 articles; eight studies with eight instruments met criteria for inclusion. Data abstraction on theoretical framework, subjects, instrument description, scoring, method of measurement, reliability, validity, feasibility, level of evidence, and outcomes was completed. Reliability information was provided in five studies with an internal consistency of Cronbach's α >0.70. Information pertaining to validity was presented in three studies and included construct validity via factor analysis. Despite limited psychometric information, these questionnaires are self-administered and can be briefly completed, making them a feasible method of evaluation.
Neimeyer, Robert A; Kazantzis, Nikolaos; Kassler, Dina M; Baker, Kurt D; Fletcher, Richard
2008-01-01
There is a need to understand the mechanism through which homework contributes to clinically meaningful change in therapy. Theoretically meaningful factors such as willingness to complete therapeutic assignments and cognitive skill acquisition have not been carefully studied in prior research. Depressed outpatients (N = 46) received cognitive behavioural group therapy for a 10-week period and were assigned relevant homework activities. Patient self-report and independent ratings of homework compliance were obtained on a session-by-session basis. Using path analysis, the authors found evidence that willingness to complete homework assignments and mastery of skill in cognitive restructuring helped account for the relationship between homework compliance and reduced symptom severity (R2 = .40). However, paths were only significant when patient self-report of homework compliance was used in the model. The present study highlights the problems in assessing homework compliance and in assuming that independent assessment of compliance is more accurate than patient self-report.
Transonic flow past a wedge profile with detached bow wave
NASA Technical Reports Server (NTRS)
Vincenti, Walter G; Wagoner, Cleo B
1952-01-01
A theoretical study has been made of the aerodynamic characteristics at zero angle of attack of a thin, doubly symmetrical double-wedge profile in the range of supersonic flight speed in which the bow wave is detached. The analysis utilizes the equations of the transonic small-disturbance theory and involves no assumptions beyond those implicit in this theory. The mixed flow about the front half of the profile is calculated by relaxation solution of boundary conditions along the shock polar and sonic line. The purely subsonic flow about the rear of the profile is found by means of the method of characteristics specialized to the transonic small-disturbance theory. Complete calculations were made for four values of the transonic similarity parameter. These were found sufficient to bridge the gap between the previous results of Guderley and Yoshihara at a Mach number of 1 and the results which are readily obtained when the bow wave is attached and the flow is completely supersonic.
Experimental evidence of locally resonant sonic band gap in two-dimensional phononic stubbed plates
NASA Astrophysics Data System (ADS)
Oudich, Mourad; Senesi, Matteo; Assouar, M. Badreddine; Ruzenne, Massimo; Sun, Jia-Hong; Vincent, Brice; Hou, Zhilin; Wu, Tsung-Tsong
2011-10-01
We provide experimental evidence of the existence of a locally resonant sonic band gap in a two-dimensional stubbed plate. Structures consisting of a periodic arrangement of silicone rubber stubs deposited on a thin aluminium plate were fabricated and characterized. Brillouin spectroscopy analysis is carried out to determine the elastic constants of the used rubber. The constants are then implemented in an efficient finite-element model that predicts the band structure and transmission to identify the theoretical band gap. We measure a complete sonic band gap for the out-of-plane Lamb wave modes propagating in various samples fabricated with different stub heights. Frequency domain measurements of full wave field and transmission are performed through a scanning laser Doppler vibrometer. A complete band gap from 1.9 to 2.6 kHz is showed using a sample with 6-mm stub diameter, 5-mm thickness, and 1-cm structure periodicity. Very good agreement between numerical and experimental results is obtained.
Quick, Brian L; Anker, Ashley E; Feeley, Thomas Hugh; Morgan, Susan E
2016-01-01
An inconsistency in the research indicates positive attitudes toward organ donation do not map reliably onto organ donor registrations. Various models have sought to explain this inconsistency and the current analysis formally compared three models: the Bystander Intervention Model (BIM), the Organ Donor Model (ODM), and Vested Interest Theory (VIT). Mature (N = 688) adults between the ages of 50 to 64 years completed surveys related to organ donation. Results revealed that VIT accounted for the most variance in organ donation registrations followed by the BIM and ODM. The discussion emphasizes the importance of employing theories to explain a phenomenon as well as the practical implications of the findings.
Lucklum, Ralf; Zubtsov, Mikhail; Schmidt, Marc-Peter; Mukhin, Nikolay V.; Hirsch, Soeren
2017-01-01
The current work demonstrates a novel surface acoustic wave (SAW) based phononic crystal sensor approach that allows the integration of a velocimetry-based sensor concept into single chip integrated solutions, such as Lab-on-a-Chip devices. The introduced sensor platform merges advantages of ultrasonic velocimetry analytic systems and a microacoustic sensor approach. It is based on the analysis of structural resonances in a periodic composite arrangement of microfluidic channels confined within a liquid analyte. Completed theoretical and experimental investigations show the ability to utilize periodic structure localized modes for the detection of volumetric properties of liquids and prove the efficacy of the proposed sensor concept. PMID:28946609
Oseev, Aleksandr; Lucklum, Ralf; Zubtsov, Mikhail; Schmidt, Marc-Peter; Mukhin, Nikolay V; Hirsch, Soeren
2017-09-23
The current work demonstrates a novel surface acoustic wave (SAW) based phononic crystal sensor approach that allows the integration of a velocimetry-based sensor concept into single chip integrated solutions, such as Lab-on-a-Chip devices. The introduced sensor platform merges advantages of ultrasonic velocimetry analytic systems and a microacoustic sensor approach. It is based on the analysis of structural resonances in a periodic composite arrangement of microfluidic channels confined within a liquid analyte. Completed theoretical and experimental investigations show the ability to utilize periodic structure localized modes for the detection of volumetric properties of liquids and prove the efficacy of the proposed sensor concept.
NASA Astrophysics Data System (ADS)
Yoshida, Takahiko; Tokizaki, Chihiro; Takayanagi, Toshiyuki
2015-08-01
A three degree-of-freedom potential energy surface of the cyclooctatetraene (COT) unimolecular reaction that can describe both ring-inversion (D2d ↔ D2d) and double bond-alternation (D4h ↔ D4h) processes was constructed using complete active space self-consistent field calculations. The potential energy surface was used to simulate the experimentally measured transition-state spectrum by calculating the photodetachment spectrum of the COT anion with time-dependent wave packet formalism. The calculated spectrum reproduces the experimental result well. We also analyzed wavefunction properties at spectral peak positions to understand the COT unimolecular reaction dynamics.
Galilean symmetry in a noncommutative gravitational quantum well
DOE Office of Scientific and Technical Information (OSTI.GOV)
Saha, Anirban
2010-06-15
A thorough analysis of Galilean symmetries for the gravitational well problem on a noncommutative plane is presented. A complete closure of the one-parameter centrally extended Galilean algebra is realized for the model. This implies that the field theoretic model constructed to describe noncommutative gravitational quantum well in [A. Saha, Eur. Phys. J. C 51, 199 (2007).] is indeed independent of the coordinate choice. Hence the energy spectrum predicted by the model can be associated with the experimental results to establish the upper bound on a time-space noncommutative parameter. Interestingly, noncommutativity is shown to increase the gravitational pull on the neutronmore » trapped in the gravitational well.« less
NASA Astrophysics Data System (ADS)
Sood, R. K.; Waldron, L.; Rochester, G. K.; Sumner, T. J.; Frye, G.; Jenkins, T.; Staubert, R.; Kendziorra, E.; Ubertini, P.; Bazzano, A.
1992-08-01
Analysis of the data obtained from two flights of a balloonborne gamma-ray detector to observe SN 1987A was completed. The detector, which included a spark chamber to determine the arrival directions of the photons, was sensitive in the energy range 50-500 MeV. The 95 percent confidence upper limit to the flux on day 55 after the explosion has been established to be 1.1 x 10 exp -5 photons/sq cm/s and on day 407 to be 3.4 x 10 exp -5 photons/sq cm/s. These limits are compared with various theoretical predictions.
NASA Astrophysics Data System (ADS)
Šantić, Neven; Fusaro, Adrien; Salem, Sabeur; Garnier, Josselin; Picozzi, Antonio; Kaiser, Robin
2018-02-01
The nonlinear Schrödinger equation, used to describe the dynamics of quantum fluids, is known to be valid not only for massive particles but also for the propagation of light in a nonlinear medium, predicting condensation of classical waves. Here we report on the initial evolution of random waves with Gaussian statistics using atomic vapors as an efficient two dimensional nonlinear medium. Experimental and theoretical analysis of near field images reveal a phenomenon of nonequilibrium precondensation, characterized by a fast relaxation towards a precondensate fraction of up to 75%. Such precondensation is in contrast to complete thermalization to the Rayleigh-Jeans equilibrium distribution, requiring prohibitive long interaction lengths.
Integrated Education in Conflicted Societies: Is There a Need for New Theoretical Language?
ERIC Educational Resources Information Center
Zembylas, Michalinos; Bekerman, Zvi
2013-01-01
This article takes on the issue of "integrated education" in conflicted societies and engages in a deeper analysis of its dominant theoretical concepts, approaches, and implications. This analysis suggests that the theoretical language that drives current approaches of integrated education may unintentionally be complicit to the project…
Multiple Imputation for Incomplete Data in Epidemiologic Studies
Harel, Ofer; Mitchell, Emily M; Perkins, Neil J; Cole, Stephen R; Tchetgen Tchetgen, Eric J; Sun, BaoLuo; Schisterman, Enrique F
2018-01-01
Abstract Epidemiologic studies are frequently susceptible to missing information. Omitting observations with missing variables remains a common strategy in epidemiologic studies, yet this simple approach can often severely bias parameter estimates of interest if the values are not missing completely at random. Even when missingness is completely random, complete-case analysis can reduce the efficiency of estimated parameters, because large amounts of available data are simply tossed out with the incomplete observations. Alternative methods for mitigating the influence of missing information, such as multiple imputation, are becoming an increasing popular strategy in order to retain all available information, reduce potential bias, and improve efficiency in parameter estimation. In this paper, we describe the theoretical underpinnings of multiple imputation, and we illustrate application of this method as part of a collaborative challenge to assess the performance of various techniques for dealing with missing data (Am J Epidemiol. 2018;187(3):568–575). We detail the steps necessary to perform multiple imputation on a subset of data from the Collaborative Perinatal Project (1959–1974), where the goal is to estimate the odds of spontaneous abortion associated with smoking during pregnancy. PMID:29165547
Wang, Yongkang; Song, Xiaodan; Li, Xiaorong; Yang, Sang-tian; Zou, Xiang
2017-01-04
To explore the genome sequence of Aureobasidium pullulans CCTCC M2012223, analyze the key genes related to the biosynthesis of important metabolites, and provide genetic background for metabolic engineering. Complete genome of A. pullulans CCTCC M2012223 was sequenced by Illumina HiSeq high throughput sequencing platform. Then, fragment assembly, gene prediction, functional annotation, and GO/COG cluster were analyzed in comparison with those of other five A. pullulans varieties. The complete genome sequence of A. pullulans CCTCC M2012223 was 30756831 bp with an average GC content of 47.49%, and 9452 genes were successfully predicted. Genome-wide analysis showed that A. pullulans CCTCC M2012223 had the biggest genome assembly size. Protein sequences involved in the pullulan and polymalic acid pathway were highly conservative in all of six A. pullulans varieties. Although both A. pullulans CCTCC M2012223 and A. pullulans var. melanogenum have a close affinity, some point mutation and inserts were occurred in protein sequences involved in melanin biosynthesis. Genome information of A. pullulans CCTCC M2012223 was annotated and genes involved in melanin, pullulan and polymalic acid pathway were compared, which would provide a theoretical basis for genetic modification of metabolic pathway in A. pullulans.
Sorimachi, Kenji; Okayasu, Teiji; Ohhira, Shuji
2015-04-01
Normalized nucleotide and amino acid contents of complete genome sequences can be visualized as radar charts. The shapes of these charts depict the characteristics of an organism's genome. The normalized values calculated from the genome sequence theoretically exclude experimental errors. Further, because normalization is independent of both target size and kind, this procedure is applicable not only to single genes but also to whole genomes, which consist of a huge number of different genes. In this review, we discuss the applications of the normalization of the nucleotide and predicted amino acid contents of complete genomes to the investigation of genome structure and to evolutionary research from primitive organisms to Homo sapiens. Some of the results could never have been obtained from the analysis of individual nucleotide or amino acid sequences but were revealed only after the normalization of nucleotide and amino acid contents was applied to genome research. The discovery that genome structure was homogeneous was obtained only after normalization methods were applied to the nucleotide or predicted amino acid contents of genome sequences. Normalization procedures are also applicable to evolutionary research. Thus, normalization of the contents of whole genomes is a useful procedure that can help to characterize organisms.
Di Fabio, Annamaria; Kenny, Maureen E.
2016-01-01
The aim of the present study is to empirically test the theoretical model, Positive Self and Relational Management (PS&RM), for a sample of 184 Italian university students. The PS&RM model specifies the development of individuals' strengths, potentials, and talents across the lifespan and with regard to the dialect of self in relationship. PS&RM is defined theoretically by three constructs: Positive Lifelong Life Management, Positive Lifelong Self-Management, Positive Lifelong Relational Management. The three constructs are operationalized as follows: Positive Lifelong Life Management is measured by the Positive and Negative Affect Schedule (PANAS), the Satisfaction With Life Scale (SWLS), the Meaningful Life Measure (MLM), and the Authenticity Scale (AS); Positive Lifelong Self-Management is measured by the Intrapreneurial Self-Capital Scale (ISC), the Career Adapt-Abilities Scale (CAAS), and the Life Project Reflexivity Scale (LPRS); and Positive Lifelong Relational Management is measured by the Trait Emotional Intelligence Questionnaire (TEIQue), the Multidimensional Scale for Perceived Social Support (MSPSS), and the Positive Relational Management Scale (PRMS). Confirmatory factor analysis of the PS&RM model was completed using structural equation modeling. The theoretical PS&RM model was empirically tested as defined by the three hypothesized constructs. Empirical support for this model offers a framework for further research and the design of preventive interventions to promote decent work and decent lives in the twenty-first century. PMID:27047406
Exploring patient satisfaction predictors in relation to a theoretical model.
Grøndahl, Vigdis Abrahamsen; Hall-Lord, Marie Louise; Karlsson, Ingela; Appelgren, Jari; Wilde-Larsson, Bodil
2013-01-01
The aim is to describe patients' care quality perceptions and satisfaction and to explore potential patient satisfaction predictors as person-related conditions, external objective care conditions and patients' perception of actual care received ("PR") in relation to a theoretical model. A cross-sectional design was used. Data were collected using one questionnaire combining questions from four instruments: Quality from patients' perspective; Sense of coherence; Big five personality trait; and Emotional stress reaction questionnaire (ESRQ), together with questions from previous research. In total, 528 patients (83.7 per cent response rate) from eight medical, three surgical and one medical/surgical ward in five Norwegian hospitals participated. Answers from 373 respondents with complete ESRQ questionnaires were analysed. Sequential multiple regression analysis with ESRQ as dependent variable was run in three steps: person-related conditions, external objective care conditions, and PR (p < 0.05). Step 1 (person-related conditions) explained 51.7 per cent of the ESRQ variance. Step 2 (external objective care conditions) explained an additional 2.4 per cent. Step 3 (PR) gave no significant additional explanation (0.05 per cent). Steps 1 and 2 contributed statistical significance to the model. Patients rated both quality-of-care and satisfaction highly. The paper shows that the theoretical model using an emotion-oriented approach to assess patient satisfaction can explain 54 per cent of patient satisfaction in a statistically significant manner.
Johnson, Suzanne; Price, Matthew; Mehta, Natasha; Anderson, Page L
2014-08-19
There are high attrition rates observed in efficacy studies for social anxiety disorder, and research has not identified consistent nor theoretically meaningful predictors of dropout. Pre-treatment symptom severity and demographic factors, such as age and gender, are sometimes predictive of dropout. The current study examines a theoretically meaningful predictor of attrition based on experiences associated with social group membership rather than differences between social group categories--fear of confirming stereotypes. This is a secondary data analysis of a randomized controlled trial comparing two cognitive behavioral treatments for social anxiety disorder: virtual reality exposure therapy and exposure group therapy. Participants (N = 74) with a primary diagnosis of social anxiety disorder who were eligible to participate in the parent study and who self-identified as either "African American" (n = 31) or "Caucasian" (n = 43) completed standardized self-report measures of stereotype confirmation concerns (SCC) and social anxiety symptoms as part of a pre-treatment assessment battery. Hierarchical logistic regression showed that greater stereotype confirmation concerns were associated with higher dropout from therapy--race, age, gender, and pre-treatment symptom severity were not. Group treatment also was associated with higher dropout. These findings urge further research on theoretically meaningful predictors of attrition and highlight the importance of addressing cultural variables, such as the experience of stereotype confirmation concerns, during treatment of social anxiety to minimize dropout from therapy.
Doyle, F; McGee, H M; Conroy, R M; Delaney, M
2011-05-01
Depression is associated with increased cardiovascular risk in acute coronary syndrome (ACS) patients, but some argue that elevated depression is actually a marker of cardiovascular disease severity. Therefore, disease indices should better predict depression than established theoretical causes of depression (interpersonal life events, reinforcing events, cognitive distortions, type D personality). However, little theory-based research has been conducted in this area. In a cross-sectional design, ACS patients (n = 336) completed questionnaires assessing depression and psychosocial vulnerabilities. Nested logistic regression assessed the relative contribution of demographic or vulnerability factors, or disease indices or vulnerabilities to depression. In multivariate analysis, all vulnerabilities were independent significant predictors of depression (scoring above threshold on any scale, 48%). Demographic variables accounted for <1% of the variance of depression status, with vulnerabilities accounting for significantly more (pseudo R² = 0.16, χ²(change) = 150.9, df = 4, p < 0.001). Disease indices accounted for 7% of the variance in depression (pseudo R² = 0.07, χ² = 137.9, p < 0.001). However, adding the vulnerabilities increased the overall variance explained to 22% (pseudo R² = 0.22, χ² = 58.6, df = 4, p < 0.001). Theoretical vulnerabilities predicted depression status better than did either demographic or disease indices. The presence of these proximal causes of depression suggests that depression in ACS patients is not simply a result of cardiovascular disease severity.
O'Connell, Kathryn A; Skevington, Suzanne M
2010-11-01
The study investigates theoretical debates on the contribution of spiritual, religious, and personal beliefs (SRPB) to quality of life (QoL) in health, by examining contrasting models. The WHOQOL-SRPB assesses QoL relating to SRPB where 33 QoL facets are scored in 6 domains, of which SRPB is one. The measure was completed by a heterogeneous sample of 285 sick and well people representing a cross-section of religious, agnostic, and atheist beliefs in UK, and structured for gender (52% female) and age (mean 47 years). No evidence was found to support the model of spiritual QoL as a concept that overarches every other QoL domain. Confirmatory factor analysis showed that SRPB is an integral concept to overall QoL, with a very good fit (comparative fit index=.99). Spiritual QoL made a significant, relatively independent contribution, similar to the other five domains (β=0.68). Spiritual QoL is most closely associated with the psychological domain, particularly hope and optimism and inner peace; two of the nine SRPB facets. Spiritual QoL, but not most other aspects of QoL, is higher for religious people. The results explain theoretical confusion arising from previous research. Spiritual QoL makes a significant and distinctive contribution to QoL assessment in health and should be assessed routinely in health care populations.
ERIC Educational Resources Information Center
Petty, Barrett Wade McCoy
2015-01-01
The study examined factors that predicted the completion of programs of study at Arkansas institutions of higher education for African American males. Astin's (1993a) Input-Environment-Output (I-E-O) Model was used as the theoretical foundation. Descriptive analyses and hierarchical logistic regression analyses were performed on the data. The…
Convolved substructure: analytically decorrelating jet substructure observables
NASA Astrophysics Data System (ADS)
Moult, Ian; Nachman, Benjamin; Neill, Duff
2018-05-01
A number of recent applications of jet substructure, in particular searches for light new particles, require substructure observables that are decorrelated with the jet mass. In this paper we introduce the Convolved SubStructure (CSS) approach, which uses a theoretical understanding of the observable to decorrelate the complete shape of its distribution. This decorrelation is performed by convolution with a shape function whose parameters and mass dependence are derived analytically. We consider in detail the case of the D 2 observable and perform an illustrative case study using a search for a light hadronically decaying Z'. We find that the CSS approach completely decorrelates the D 2 observable over a wide range of masses. Our approach highlights the importance of improving the theoretical understanding of jet substructure observables to exploit increasingly subtle features for performance.
NASA Astrophysics Data System (ADS)
Zitrin, Adi; Broadhurst, Tom; Barkana, Rennan; Rephaeli, Yoel; Benítez, Narciso
2011-01-01
We present the results of a strong-lensing analysis of a complete sample of 12 very luminous X-ray clusters at z > 0.5 using HST/ACS images. Our modelling technique has uncovered some of the largest known critical curves outlined by many accurately predicted sets of multiple images. The distribution of Einstein radii has a median value of ≃28 arcsec (for a source redshift of zs˜ 2), twice as large as other lower z samples, and extends to 55 arcsec for MACS J0717.5+3745, with an impressive enclosed Einstein mass of 7.4 × 1014 M⊙. We find that nine clusters cover a very large area (>2.5 arcmin2) of high magnification (μ > 10×) for a source redshift of zs˜ 8, providing primary targets for accessing the first stars and galaxies. We compare our results with theoretical predictions of the standard Λ cold dark matter (ΛCDM) model which we show systematically fall short of our measured Einstein radii by a factor of ≃1.4, after accounting for the effect of lensing projection. Nevertheless, a revised analysis, once arc redshifts become available, and similar analyses of larger samples, is needed in order to establish more precisely the level of discrepancy with ΛCDM predictions.
Advanced Signal Processing Methods Applied to Digital Mammography
NASA Technical Reports Server (NTRS)
Stauduhar, Richard P.
1997-01-01
The work reported here is on the extension of the earlier proposal of the same title, August 1994-June 1996. The report for that work is also being submitted. The work reported there forms the foundation for this work from January 1997 to September 1997. After the earlier work was completed there were a few items that needed to be completed prior to submission of a new and more comprehensive proposal for further research. Those tasks have been completed and two new proposals have been submitted, one to NASA, and one to Health & Human Services WS). The main purpose of this extension was to refine some of the techniques that lead to automatic large scale evaluation of full mammograms. Progress on each of the proposed tasks follows. Task 1: A multiresolution segmentation of background from breast has been developed and tested. The method is based on the different noise characteristics of the two different fields. The breast field has more power in the lower octaves and the off-breast field behaves similar to a wideband process, where more power is in the high frequency octaves. After the two fields are separated by lowpass filtering, a region labeling routine is used to find the largest contiguous region, the breast. Task 2: A wavelet expansion that can decompose the image without zero padding has been developed. The method preserves all properties of the power-of-two wavelet transform and does not add appreciably to computation time or storage. This work is essential for analysis of the full mammogram, as opposed to selecting sections from the full mammogram. Task 3: A clustering method has been developed based on a simple counting mechanism. No ROC analysis has been performed (and was not proposed), so we cannot finally evaluate this work without further support. Task 4: Further testing of the filter reveals that different wavelet bases do yield slightly different qualitative results. We cannot provide quantitative conclusions about this for all possible bases without further support. Task 5: Better modeling does indeed make an improvement in the detection output. After the proposal ended, we came up with some new theoretical explanations that helps in understanding when the D4 filter should be better. This work is currently in the review process. Task 6: N/A. This no longer applies in view of Tasks 4-5. Task 7: Comprehensive plans for further work have been completed. These plans are the subject of two proposals, one to NASA and one to HHS. These proposals represent plans for a complete evaluation of the methods for identifying normal mammograms, augmented with significant further theoretical work.
On the Correct Analysis of the Foundations of Theoretical Physics
NASA Astrophysics Data System (ADS)
Kalanov, Temur Z.
2007-04-01
The problem of truth in science -- the most urgent problem of our time -- is discussed. The correct theoretical analysis of the foundations of theoretical physics is proposed. The principle of the unity of formal logic and rational dialectics is a methodological basis of the analysis. The main result is as follows: the generally accepted foundations of theoretical physics (i.e. Newtonian mechanics, Maxwell electrodynamics, thermodynamics, statistical physics and physical kinetics, the theory of relativity, quantum mechanics) contain the set of logical errors. These errors are explained by existence of the global cause: the errors are a collateral and inevitable result of the inductive way of cognition of the Nature, i.e. result of movement from formation of separate concepts to formation of the system of concepts. Consequently, theoretical physics enters the greatest crisis. It means that physics as a science of phenomenon leaves the progress stage for a science of essence (information). Acknowledgment: The books ``Surprises in Theoretical Physics'' (1979) and ``More Surprises in Theoretical Physics'' (1991) by Sir Rudolf Peierls stimulated my 25-year work.
Transition for Whom? Adolescence Theories with Androcentric Bias
ERIC Educational Resources Information Center
Murty, Lakshmi
1978-01-01
Suggests that theoretical expositions of adolescence have completely ignored the differential effects of industrialization on males and females and have utilized a single explanation for both sexes. (Author/AM)
Analysis of an experiment aimed at improving the reliability of transmission centre shafts.
Davis, T P
1995-01-01
Smith (1991) presents a paper proposing the use of Weibull regression models to establish dependence of failure data (usually times) on covariates related to the design of the test specimens and test procedures. In his article Smith made the point that good experimental design was as important in reliability applications as elsewhere, and in view of the current interest in design inspired by Taguchi and others, we pay some attention in this article to that topic. A real case study from the Ford Motor Company is presented. Our main approach is to utilize suggestions in the literature for applying standard least squares techniques of experimental analysis even when there is likely to be nonnormal error, and censoring. This approach lacks theoretical justification, but its appeal is its simplicity and flexibility. For completeness we also include some analysis based on the proportional hazards model, and in an attempt to link back to Smith (1991), look at a Weibull regression model.
TOPICAL REVIEW: Human soft tissue analysis using x-ray or gamma-ray techniques
NASA Astrophysics Data System (ADS)
Theodorakou, C.; Farquharson, M. J.
2008-06-01
This topical review is intended to describe the x-ray techniques used for human soft tissue analysis. X-ray techniques have been applied to human soft tissue characterization and interesting results have been presented over the last few decades. The motivation behind such studies is to provide improved patient outcome by using the data obtained to better understand a disease process and improve diagnosis. An overview of theoretical background as well as a complete set of references is presented. For each study, a brief summary of the methodology and results is given. The x-ray techniques include x-ray diffraction, x-ray fluorescence, Compton scattering, Compton to coherent scattering ratio and attenuation measurements. The soft tissues that have been classified using x-rays or gamma rays include brain, breast, colon, fat, kidney, liver, lung, muscle, prostate, skin, thyroid and uterus.
Isomers and energy landscapes of micro-hydrated sulfite and chlorate clusters
NASA Astrophysics Data System (ADS)
Hey, John C.; Doyle, Emily J.; Chen, Yuting; Johnston, Roy L.
2018-03-01
We present putative global minima for the micro-hydrated sulfite SO32-(H2O)N and chlorate ClO32(H2O)N systems in the range 3≤N≤15 found using basin-hopping global structure optimization with an empirical potential. We present a structural analysis of the hydration of a large number of minimized structures for hydrated sulfite and chlorate clusters in the range 3≤N≤50. We show that sulfite is a significantly stronger net acceptor of hydrogen bonding within water clusters than chlorate, completely suppressing the appearance of hydroxyl groups pointing out from the cluster surface (dangling OH bonds), in low-energy clusters. We also present a qualitative analysis of a highly explored energy landscape in the region of the global minimum of the eight water hydrated sulfite and chlorate systems. This article is part of the theme issue `Modern theoretical chemistry'.
Unified theory of inertial granular flows and non-Brownian suspensions.
DeGiuli, E; Düring, G; Lerner, E; Wyart, M
2015-06-01
Rheological properties of dense flows of hard particles are singular as one approaches the jamming threshold where flow ceases both for aerial granular flows dominated by inertia and for over-damped suspensions. Concomitantly, the length scale characterizing velocity correlations appears to diverge at jamming. Here we introduce a theoretical framework that proposes a tentative, but potentially complete, scaling description of stationary flows. Our analysis, which focuses on frictionless particles, applies both to suspensions and inertial flows of hard particles. We compare our predictions with the empirical literature, as well as with novel numerical data. Overall, we find a very good agreement between theory and observations, except for frictional inertial flows whose scaling properties clearly differ from frictionless systems. For overdamped flows, more observations are needed to decide if friction is a relevant perturbation. Our analysis makes several new predictions on microscopic dynamical quantities that should be accessible experimentally.
Multiwire proportional chamber development
NASA Technical Reports Server (NTRS)
Doolittle, R. F.; Pollvogt, U.; Eskovitz, A. J.
1973-01-01
The development of large area multiwire proportional chambers, to be used as high resolution spatial detectors in cosmic ray experiments is described. A readout system was developed which uses a directly coupled, lumped element delay-line whose characteristics are independent of the MWPC design. A complete analysis of the delay-line and the readout electronic system shows that a spatial resolution of about 0.1 mm can be reached with the MWPC operating in the strictly proportional region. This was confirmed by measurements with a small MWPC and Fe-55 X-rays. A simplified analysis was carried out to estimate the theoretical limit of spatial resolution due to delta-rays, spread of the discharge along the anode wire, and inclined trajectories. To calculate the gas gain of MWPC's of different geometrical configurations a method was developed which is based on the knowledge of the first Townsend coefficient of the chamber gas.
Tao, Donghua
2008-01-01
This study extended the Technology Acceptance Model (TAM) by examining the roles of two aspects of e-resource characteristics, namely, information quality and system quality, in predicting public health students’ intention to use e-resources for completing research paper assignments. Both focus groups and a questionnaire were used to collect data. Descriptive analysis, data screening, and Structural Equation Modeling (SEM) techniques were used for data analysis. The study found that perceived usefulness played a major role in determining students’ intention to use e-resources. Perceived usefulness and perceived ease of use fully mediated the impact that information quality and system quality had on behavior intention. The research model enriches the existing technology acceptance literature by extending TAM. Representing two aspects of e-resource characteristics provides greater explanatory information for diagnosing problems of system design, development, and implementation. PMID:18999300
Tao, Donghua
2008-11-06
This study extended the Technology Acceptance Model (TAM) by examining the roles of two aspects of e-resource characteristics, namely, information quality and system quality, in predicting public health students' intention to use e-resources for completing research paper assignments. Both focus groups and a questionnaire were used to collect data. Descriptive analysis, data screening, and Structural Equation Modeling (SEM) techniques were used for data analysis. The study found that perceived usefulness played a major role in determining students' intention to use e-resources. Perceived usefulness and perceived ease of use fully mediated the impact that information quality and system quality had on behavior intention. The research model enriches the existing technology acceptance literature by extending TAM. Representing two aspects of e-resource characteristics provides greater explanatory information for diagnosing problems of system design, development, and implementation.
Electronic inhomogeneity in a Kondo lattice
Bauer, E. D.; Yang, Yi-feng; Capan, C.; Urbano, R. R.; Miclea, C. F.; Sakai, H.; Ronning, F.; Graf, M. J.; Balatsky, A. V.; Movshovich, R.; Bianchi, A. D.; Reyes, A. P.; Kuhns, P. L.; Thompson, J. D.; Fisk, Z.
2011-01-01
Inhomogeneous electronic states resulting from entangled spin, charge, and lattice degrees of freedom are hallmarks of strongly correlated electron materials; such behavior has been observed in many classes of d-electron materials, including the high-Tc copper-oxide superconductors, manganites, and most recently the iron–pnictide superconductors. The complexity generated by competing phases in these materials constitutes a considerable theoretical challenge—one that still defies a complete description. Here, we report a manifestation of electronic inhomogeneity in a strongly correlated f-electron system, using CeCoIn5 as an example. A thermodynamic analysis of its superconductivity, combined with nuclear quadrupole resonance measurements, shows that nonmagnetic impurities (Y, La, Yb, Th, Hg, and Sn) locally suppress unconventional superconductivity, generating an inhomogeneous electronic “Swiss cheese” due to disrupted periodicity of the Kondo lattice. Our analysis may be generalized to include related systems, suggesting that electronic inhomogeneity should be considered broadly in Kondo lattice materials.
Analysis on trust influencing factors and trust model from multiple perspectives of online Auction
NASA Astrophysics Data System (ADS)
Yu, Wang
2017-10-01
Current reputation models lack the research on online auction trading completely so they cannot entirely reflect the reputation status of users and may cause problems on operability. To evaluate the user trust in online auction correctly, a trust computing model based on multiple influencing factors is established. It aims at overcoming the efficiency of current trust computing methods and the limitations of traditional theoretical trust models. The improved model comprehensively considers the trust degree evaluation factors of three types of participants according to different participation modes of online auctioneers, to improve the accuracy, effectiveness and robustness of the trust degree. The experiments test the efficiency and the performance of our model under different scale of malicious user, under environment like eBay and Sporas model. The experimental results analysis show the model proposed in this paper makes up the deficiency of existing model and it also has better feasibility.
Isomers and energy landscapes of micro-hydrated sulfite and chlorate clusters.
Hey, John C; Doyle, Emily J; Chen, Yuting; Johnston, Roy L
2018-03-13
We present putative global minima for the micro-hydrated sulfite SO 3 2- (H 2 O) N and chlorate ClO 3 - (H 2 O) N systems in the range 3≤ N ≤15 found using basin-hopping global structure optimization with an empirical potential. We present a structural analysis of the hydration of a large number of minimized structures for hydrated sulfite and chlorate clusters in the range 3≤ N ≤50. We show that sulfite is a significantly stronger net acceptor of hydrogen bonding within water clusters than chlorate, completely suppressing the appearance of hydroxyl groups pointing out from the cluster surface (dangling OH bonds), in low-energy clusters. We also present a qualitative analysis of a highly explored energy landscape in the region of the global minimum of the eight water hydrated sulfite and chlorate systems.This article is part of the theme issue 'Modern theoretical chemistry'. © 2018 The Authors.
Design and development of the mobile game based on the J2ME technology
NASA Astrophysics Data System (ADS)
He, Junhua
2011-12-01
With the continuous improvement of mobile performance, mobile entertainment applications market trend has been increasingly clear, mobile entertainment applications will be after the PC entertainment applications is another important business growth. Through the full analysis of the current mobile entertainment applications market demand and trends, the author has accumulated a lot of theoretical knowledge and practical experience. Rational, using of some new technology for a mobile entertainment games design, and described the development of key technologies required for mobile game an analysis and design of the game, and to achieve a complete game development. Light of the specific mobile game project - "Battle City", detailed the development of a mobile game based on the J2ME platform, the basic steps and the various key elements, focusing on how to use object-oriented thinking on the role of mobile phones in the abstract and Game Animation package, the source code with specific instructions.
Design and development of the mobile game based on the J2ME technology
NASA Astrophysics Data System (ADS)
He, JunHua
2012-01-01
With the continuous improvement of mobile performance, mobile entertainment applications market trend has been increasingly clear, mobile entertainment applications will be after the PC entertainment applications is another important business growth. Through the full analysis of the current mobile entertainment applications market demand and trends, the author has accumulated a lot of theoretical knowledge and practical experience. Rational, using of some new technology for a mobile entertainment games design, and described the development of key technologies required for mobile game an analysis and design of the game, and to achieve a complete game development. Light of the specific mobile game project - "Battle City", detailed the development of a mobile game based on the J2ME platform, the basic steps and the various key elements, focusing on how to use object-oriented thinking on the role of mobile phones in the abstract and Game Animation package, the source code with specific instructions.
Evaluation of innovative rocket engines for single-stage earth-to-orbit vehicles
NASA Astrophysics Data System (ADS)
Manski, Detlef; Martin, James A.
1988-07-01
Computer models of rocket engines and single-stage-to-orbit vehicles that were developed by the authors at DFVLR and NASA have been combined. The resulting code consists of engine mass, performance, trajectory and vehicle sizing models. The engine mass model includes equations for each subsystem and describes their dependences on various propulsion parameters. The engine performance model consists of multidimensional sets of theoretical propulsion properties and a complete thermodynamic analysis of the engine cycle. The vehicle analyses include an optimized trajectory analysis, mass estimation, and vehicle sizing. A vertical-takeoff, horizontal-landing, single-stage, winged, manned, fully reusable vehicle with a payload capability of 13.6 Mg (30,000 lb) to low earth orbit was selected. Hydrogen, methane, propane, and dual-fuel engines were studied with staged-combustion, gas-generator, dual bell, and the dual-expander cycles. Mixture ratio, chamber pressure, nozzle exit pressure liftoff acceleration, and dual fuel propulsive parameters were optimized.
Evaluation of innovative rocket engines for single-stage earth-to-orbit vehicles
NASA Technical Reports Server (NTRS)
Manski, Detlef; Martin, James A.
1988-01-01
Computer models of rocket engines and single-stage-to-orbit vehicles that were developed by the authors at DFVLR and NASA have been combined. The resulting code consists of engine mass, performance, trajectory and vehicle sizing models. The engine mass model includes equations for each subsystem and describes their dependences on various propulsion parameters. The engine performance model consists of multidimensional sets of theoretical propulsion properties and a complete thermodynamic analysis of the engine cycle. The vehicle analyses include an optimized trajectory analysis, mass estimation, and vehicle sizing. A vertical-takeoff, horizontal-landing, single-stage, winged, manned, fully reusable vehicle with a payload capability of 13.6 Mg (30,000 lb) to low earth orbit was selected. Hydrogen, methane, propane, and dual-fuel engines were studied with staged-combustion, gas-generator, dual bell, and the dual-expander cycles. Mixture ratio, chamber pressure, nozzle exit pressure liftoff acceleration, and dual fuel propulsive parameters were optimized.
NASA Astrophysics Data System (ADS)
Gweon, Gey-Hong; Lee, Hee-Sun; Dorsey, Chad; Tinker, Robert; Finzer, William; Damelin, Daniel
2015-03-01
In tracking student learning in on-line learning systems, the Bayesian knowledge tracing (BKT) model is a popular model. However, the model has well-known problems such as the identifiability problem or the empirical degeneracy problem. Understanding of these problems remain unclear and solutions to them remain subjective. Here, we analyze the log data from an online physics learning program with our new model, a Monte Carlo BKT model. With our new approach, we are able to perform a completely unbiased analysis, which can then be used for classifying student learning patterns and performances. Furthermore, a theoretical analysis of the BKT model and our computational work shed new light on the nature of the aforementioned problems. This material is based upon work supported by the National Science Foundation under Grant REC-1147621 and REC-1435470.
Arivazhagan, M; Kavitha, R; Subhasini, V P
2014-07-15
The detailed HF and B3LYP/6-311++G(d,p) comparative studies on the complete FT-IR and FT-Raman spectra of 6-methoxy-1,2,3,4-tetrahydronaphthalene [MTHN] have been studied. In view of the special properties and uses, the present investigation has been undertaken to provide a satisfactorily vibrational analysis of 6-methoxy-1,2,3,4-tetrahydronaphthalene. Therefore, a thorough Raman, IR, molecular electrostatic potential (MESP), non-linear optical (NLO) properties, UV-VIS, HOMO-LUMO and NMR spectroscopic investigation are reported complemented by B3LYP theoretical predictions with basis set 6-311++G(d,p) to provide novel insight on vibrational assignments and conformational stability of MTHN. Potential energy surface scans (PES) of the CH3 group are undertaken to shed light on the rather complicated conformational interchanges in the compound under investigation. Copyright © 2014 Elsevier B.V. All rights reserved.
FTIR, FT-Raman, FT-NMR and quantum chemical investigations of 3-acetylcoumarin
NASA Astrophysics Data System (ADS)
Arjunan, V.; Sakiladevi, S.; Marchewka, M. K.; Mohan, S.
2013-05-01
3-Acetylcoumarin (3AC) was synthesised by a Knoevenagel reaction. Conformational analysis using the B3LYP method was also carried out to determine the most stable conformation of the compound. FTIR and FT-Raman spectra of 3AC have been recorded in the range 4000-400 and 4000-100 cm-1, respectively. 1H and 13C NMR spectra have also been recorded. The complete vibrational assignment and analysis of the fundamental modes of the compound were carried out using the experimental FTIR and FT-Raman data and quantum mechanical studies. The experimental vibrational frequencies were compared with the wavenumbers obtained theoretically from the DFT-B3LYP/B3PW91 gradient calculations employing the standard 6-31G**, high level 6-311++G** and cc-pVTZ basis sets for optimised geometry of the compound. The frontier molecular orbital energies of the compound are determined by DFT method.
Complete home smoking bans and antitobacco contingencies: a natural experiment.
Hovell, Melbourne F; Adams, Marc A; Hofstetter, C Richard; Martínez-Donate, Ana P; González-Pérez, Guillermo J; Rovniak, Liza S; Boman-Davis, Marie C
2014-02-01
The California antitobacco culture may have influenced home smoking bans in Mexico. Based on the Behavioral Ecological Model, exposure to socially reinforcing contingencies or criticism may explain adoption of home smoking bans in Tijuana, Mexico, approximating rates relative to San Diego, California, and higher than those in Guadalajara, Mexico. A representative cross-sectional population survey of Latinos (N = 1,901) was conducted in San Diego, Tijuana, and Guadalajara between June 2003 and September 2004. Cities were selected to represent high-, medium-, and low-level exposure to antitobacco social contingencies of reinforcement in a quasiexperimental analysis of possible cultural influences across borders. Complete home smoking ban prevalence was 91% in San Diego, 66% in Tijuana, and 38% in Guadalajara (p < .001). Sample cluster-adjusted logistic regression showed significantly lower odds of complete home smoking bans in Guadalajara (odds ratio [OR] = .048) and in Tijuana (OR = .138) compared to San Diego after control for demographics. Odds of complete home smoking bans in both Guadalajara and Tijuana in comparison with San Diego were weakened when mediators for bans were controlled in predictive models. Direction of association was consistent with theory. When theoretical mediators were explored as possible moderators, weak and nonsignificant associations were obtained for all interaction terms. Bootstrap analyses demonstrated that our multivariable logistic regression results were reliable. Results suggest that California antismoking social contingencies mediate complete home smoking bans in all 3 cities and may account for the greater effects in Tijuana contrasted with Guadalajara.
Complete Home Smoking Bans and Antitobacco Contingencies: A Natural Experiment
2014-01-01
Introduction: The California antitobacco culture may have influenced home smoking bans in Mexico. Based on the Behavioral Ecological Model, exposure to socially reinforcing contingencies or criticism may explain adoption of home smoking bans in Tijuana, Mexico, approximating rates relative to San Diego, California, and higher than those in Guadalajara, Mexico. Methods: A representative cross-sectional population survey of Latinos (N = 1,901) was conducted in San Diego, Tijuana, and Guadalajara between June 2003 and September 2004. Cities were selected to represent high-, medium-, and low-level exposure to antitobacco social contingencies of reinforcement in a quasiexperimental analysis of possible cultural influences across borders. Results: Complete home smoking ban prevalence was 91% in San Diego, 66% in Tijuana, and 38% in Guadalajara (p < .001). Sample cluster-adjusted logistic regression showed significantly lower odds of complete home smoking bans in Guadalajara (odds ratio [OR] = .048) and in Tijuana (OR = .138) compared to San Diego after control for demographics. Odds of complete home smoking bans in both Guadalajara and Tijuana in comparison with San Diego were weakened when mediators for bans were controlled in predictive models. Direction of association was consistent with theory. When theoretical mediators were explored as possible moderators, weak and nonsignificant associations were obtained for all interaction terms. Bootstrap analyses demonstrated that our multivariable logistic regression results were reliable. Conclusions: Results suggest that California antismoking social contingencies mediate complete home smoking bans in all 3 cities and may account for the greater effects in Tijuana contrasted with Guadalajara. PMID:23999652
Towards a new parameterization of ice particles growth
NASA Astrophysics Data System (ADS)
Krakovska, Svitlana; Khotyayintsev, Volodymyr; Bardakov, Roman; Shpyg, Vitaliy
2017-04-01
Ice particles are the main component of polar clouds, unlike in warmer regions. That is why correct representation of ice particle formation and growth in NWP and other numerical atmospheric models is crucial for understanding of the whole chain of water transformation, including precipitation formation and its further deposition as snow in polar glaciers. Currently, parameterization of ice in atmospheric models is among the most difficult challenges. In the presented research, we present a renewed theoretical analysis of the evolution of mixed cloud or cold fog from the moment of ice nuclei activation until complete crystallization. The simplified model is proposed that includes both supercooled cloud droplets and initially uniform particles of ice, as well as water vapor. We obtain independent dimensionless input parameters of a cloud, and find main scenarios and stages of evolution of the microphysical state of the cloud. The characteristic times and particle sizes have been found, as well as the peculiarities of microphysical processes at each stage of evolution. In the future, the proposed original and physically grounded approximations may serve as a basis for a new scientifically substantiated and numerically efficient parameterizations of microphysical processes in mixed clouds for modern atmospheric models. The relevance of theoretical analysis is confirmed by numerical modeling for a wide range of combinations of possible conditions in the atmosphere, including cold polar regions. The main conclusion of the research is that until complete disappearance of cloud droplets, the growth of ice particles occurs at a practically constant humidity corresponding to the saturated humidity over water, regardless to all other parameters of a cloud. This process can be described by the one differential equation of the first order. Moreover, a dimensionless parameter has been proposed as a quantitative criterion of a transition from dominant depositional to intense collectional growth of ice particles; it could be used in models with bulk parameterization of cloud and precipitation formation processes.
Models and strategies for electricity distribution companies in emerging economies
NASA Astrophysics Data System (ADS)
Zaragocin Espinosa, Leonardo Vicente
Unbundling and privatization have become key elements of restructuring in the Electric Power Industry of Emerging Economies. These processes have concentrated on the Generation and Transmission areas, leaving Distribution as lower priority. Based on a comparison between the old role of Distribution Companies (DISCOS) and its new potential role this study identifies the main issues and challenges that DISCOS will face in the new environment once structural and ownership changes are completed. For the specific case of DISCOS in Emerging Economies, regulatory policies are reviewed and strategies identified in order to facilitate the transition and to assist in the integration of DISCOS with other agents in the evolving electric power market. Of particular importance in this research is the analysis of the role of Energy Efficiency (EE) in the new structural and governance environment. A theoretical study of the effects of energy efficiency measures, specifically loss reduction, on price regulation is developed within a proposed regulatory regime of privatization together with Price-Cap Regulation. This theoretical benchmark is then used as a starting point for a case study, the Electric System of Ecuador, where an analysis of the current Ecuadorian price regulation scheme (the Distribution Value Added Charge, VAD, scheme) is presented and analyzed in detail. General recommendations for improving the application of the VAD pricing approach are advanced, with special reference to the current situation in Ecuador.
Goldzweig, Gil; Hasson-Ohayon, Ilanit; Meirovitz, Amichay; Braun, Michal; Hubert, Ayala; Baider, Lea
2010-11-01
The current study presents the development and the evaluation of the psychometric properties of the Cancer Perceived Agents of Social Support (CPASS). The CPASS is a new self-rating instrument devised in order to enable both cancer patients and their spouses to report on the level of perceived social support they get. The CPASS evaluates the support given by different agents of support (spouse, family, friends and spiritual or religious beliefs) in several dimensions (emotional, cognitive and instrumental). The study sample comprised 662 cancer patients and their spouses recruited during a routine medical evaluation from three major cancer centers in Israel. The participants completed the CPASS and two other standardized instruments: The ENRICH Marital Satisfaction Scale (EMS) and the Brief Symptom Inventory (BSI). Principal component analysis confirmed a three-factor structure based upon the agent of support (spouse; friends/family; spiritual/religious beliefs). Cronbach's α coefficients for the agent of support indexes were high (0.80-0.95), while Cronbach's α levels for the kind of support were lower (0.45-0.72). Smallest Space Analysis (SSA) also confirmed the theoretical structure of the CPASS. Pearson correlation coefficients to the other study variables were high and significant. As a whole, the CPASS was found to be a valid tool for the current Israeli sample. Theoretical and practical conclusions and socio-cultural implications are discussed. Copyright © 2009 John Wiley & Sons, Ltd.
NASA Astrophysics Data System (ADS)
Andriopoulos, K.; Dimas, S.; Leach, P. G. L.; Tsoubelis, D.
2009-08-01
Complete symmetry groups enable one to characterise fully a given differential equation. By considering the reversal of an approach based upon complete symmetry groups we construct new classes of differential equations which have the equations of Bateman, Monge-Ampère and Born-Infeld as special cases. We develop a symbolic algorithm to decrease the complexity of the calculations involved.
Gat, Itai; Pessach-Gelblum, Liat; Givati, Gili; Haim, Nadav; Paluch-Shimon, Shani; Unterman, Avraham; Bar-Shavit, Yochay; Grabler, Galit; Sagi, Doron; Achiron, Anat; Ziv, Amitai
2016-01-01
Introduction Patient bedside is the ideal setting for teaching physical examination, medical interviewing, and interpersonal skills. Herein we describe a novel model for bedside teaching (BST) practiced during tutor training workshop and its resulting effect on practitioners’ self assessment of teaching skills and perceptions. Methods One-day tutor training workshop included theoretical knowledge supplementation regarding tutors’ roles as well as implementing practical tools for clinical education, mainly BST model. The model, which emphasizes simultaneous clinical and communication teaching in a stepwise approach, was practiced by consecutive simulations with a gradual escalation of difficulty and adjusted instruction approaches. Pre- and post-workshop-adjusted questionnaires using a Likert scale of 1 to 4 were completed by participants and compared. Results Analysis was based on 25 out of 48 participants who completed both questionnaires. Significantly improved teaching skills were demonstrated upon workshop completion (mean 3.3, SD 0.5) compared with pre-training (mean 2.6, SD 0.6; p<0.001) with significant increase in most examined parameters. Significantly improved tutor's roles internalization was demonstrated after training completion (mean 3.7, SD 0.3) compared with pre-workshop (mean 3.5 SD 0.5; p=0.002). Discussion Successful BST involves combination of clinical and communication skills. BST model practiced during the workshop may contribute to improved teaching skills in this challenging environment. PMID:26894587
Redesigning Orientation in an Intensive Care Unit Using 2 Theoretical Models.
Kozub, Elizabeth; Hibanada-Laserna, Maribel; Harget, Gwen; Ecoff, Laurie
2015-01-01
To accommodate a higher demand for critical care nurses, an orientation program in a surgical intensive care unit was revised and streamlined. Two theoretical models served as a foundation for the revision and resulted in clear clinical benchmarks for orientation progress evaluation. The purpose of the project was to integrate theoretical frameworks into practice to improve the unit orientation program. Performance improvement methods served as a framework for the revision, and outcomes were measured before and after implementation. The revised orientation program increased 1- and 2-year nurse retention and decreased turnover. Critical care knowledge increased after orientation for both the preintervention and postintervention groups. Incorporating a theoretical basis for orientation has been shown to be successful in increasing the number of nurses completing orientation and improving retention, turnover rates, and knowledge gained.
NASA Astrophysics Data System (ADS)
Drozd, M.; Marchewka, M. K.
2006-05-01
The room temperature X-ray studies of L-lysine × tartaric acid complex are not unambiguous. The disorder of three atoms of carbon in L-lysine molecule is observed. These X-ray studies are ambiguous. The theoretical geometry study performed by DFT methods explain the most doubts which are connected with crystallographic measurements. The theoretical vibrational frequencies and potential energy distribution (PED) of L-lysine × tartaric acid were calculated by B3LYP method. The calculated frequencies were compared with experimental measured IR spectra. The complete assignment of the bands has been made on the basis of the calculated PED. The restricted Hartee-Fock (RHF) methods were used for calculation of the hyperpolarizability for investigated compound. The theoretical results are compared with experimental value of β.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Knight L.B. Jr.; Cobranchi, S.T.; Petty, J.T.
1989-01-15
The first spectroscopic study of the diatomic radical BC is reported which confirms previous theoretical predictions of a /sup 4/summation/sup -/ electronic ground state. The nuclear hyperfine interactions (A tensors) obtained for /sup 11/B, /sup 10/B, and /sup 13/C from the electron spin resonance (ESR) measurements are compared with extensive ab initio CI calculations. The BC molecule is one of the first examples of a small high spin radical for such an in-depth experimental--theoretical comparison. The electronic structure of BC obtained from an analysis of the nuclear hyperfine interaction (hfi) is compared to that obtained from a Mulliken-type population analysismore » conducted on a CI wave function which yields A/sub iso/ and A/sub dip/ results in good agreement with the observed values. The BC radical was generated by the laser vaporization of a boron--carbon mixture and trapped in neon, argon, and krypton matrices at 4 K for a complete ESR characterization. The magnetic parameters (MHz) obtained for /sup 11/B/sup 13/C in solid neon are: g/sub parallel/ = 2.0015(3); g/sub perpendicular/ = 2.0020(3); D(zfs) = 1701(2); /sup 11/B: chemically bondA/sub parallel/chemically bond = 100(1); chemically bondA/sub perpendicular/chemically bond = 79(1); /sup 13/C: chemically bondA/sub parallel/chemically bond = 5(2) and chemically bondA/sub perpendicular/chemically bond = 15(1). Based on comparison with the theoretical results, the most likely choice of signs is that all A values are positive.« less
Misleading Theoretical Assumptions in Hypertext/Hypermedia Research.
ERIC Educational Resources Information Center
Tergan, Sigmar-Olaf
1997-01-01
Reviews basic theoretical assumptions of research on learning with hypertext/hypermedia. Focuses on whether the results of research on hypertext/hypermedia-based learning support these assumptions. Results of empirical studies and theoretical analysis reveal that many research approaches have been misled by inappropriate theoretical assumptions on…
Ignition and combustion characteristics of metallized propellants
NASA Technical Reports Server (NTRS)
Mueller, D. C.; Turns, Stephen R.
1991-01-01
Over the past six months, experimental investigations were continued and theoretical work on the secondary atomization process was begun. Final shakedown of the sizing/velocity measuring system was completed and the aluminum combustion detection system was modified and tested. Atomizer operation was improved to allow steady state operation over long periods of time for several slurries. To validate the theoretical modeling, work involving carbon slurry atomization and combustion was begun and qualitative observations were made. Simultaneous measurements of aluminum slurry droplet size distributions and detection of burning aluminum particles were performed at several axial locations above the burner. The principle theoretical effort was the application of a rigid shell formation model to aluminum slurries and an investigation of the effects of various parameters on the shell formation process. This shell formation model was extended to include the process leading up to droplet disruption, and previously developed analytical models were applied to yield theoretical aluminum agglomerate ignition and combustion times. The several theoretical times were compared with the experimental results.
Chu, Adeline; Mastel-Smith, Beth
2010-01-01
Technology has a great impact on nursing practice. With the increasing numbers of older Americans using computers and the Internet in recent years, nurses have the capability to deliver effective and efficient health education to their patients and the community. Based on the theoretical framework of Bandura's self-efficacy theory, the pilot project reported findings from a 5-week computer course on Internet health searches in older adults, 65 years or older, at a senior activity learning center. Twelve participants were recruited and randomized to either the intervention or the control group. Measures of computer anxiety, computer confidence, and computer self-efficacy scores were analyzed at baseline, at the end of the program, and 6 weeks after the completion of the program. Analysis was conducted with repeated-measures analysis of variance. Findings showed participants who attended a structured computer course on Internet health information retrieval reported lowered anxiety and increased confidence and self-efficacy at the end of the 5-week program and 6 weeks after the completion of the program as compared with participants who were not in the program. The study demonstrated that a computer course can help reduce anxiety and increase confidence and self-efficacy in online health searches in older adults.
Pugi, Jakob; Carcao, Manuel; Drury, Luke J; Langer, Jacob C
2018-05-01
Laparoscopic partial splenectomy (LPS) theoretically maintains long-term splenic immune function for children with hereditary spherocytosis (HS). Our goal was to review our results after LPS and to determine if specific genetic mutations influence outcome. All children with HS undergoing LPS between 2005 and 2016 were reviewed. Thirty-one children underwent LPS (16 male) at a median age of 9 (range 2-18) years. All experienced an increase in hemoglobin and decrease in reticulocyte count early after LPS and at last follow-up. Twenty-two were sent for genetic analysis. Mutations in α-spectrin, β-spectrin, and Ankyrin were identified in 6, 5, and 11 patients, respectively. Gene mutation was not correlated with complications, perioperative transfusion, length of hospital stay, or median hemoglobin, platelet, or reticulocyte counts. Three children required completion splenectomy at 10.9, 6.9, and 3.2years post-LPS, each with a different gene mutation. LPS is effective in reversing anemia and reducing reticulocytosis. So far less than 10% have required completion splenectomy, and those children did benefit from delaying the risks of asplenia. In this preliminary analysis, genetic mutation did not influence outcome after LPS. A larger multicenter study is necessary to further investigate potential correlations with specific genetic mutations. Prognosis Study. IV. Copyright © 2018. Published by Elsevier Inc.
Theoretical framework of the causes of construction time and cost overruns
NASA Astrophysics Data System (ADS)
Ullah, K.; Abdullah, A. H.; Nagapan, S.; Suhoo, S.; Khan, M. S.
2017-11-01
Any construction practitioner fundamental goal is to complete the projects within estimated duration and budgets, and expected quality targets. However, time and cost overruns are regular and universal phenomenon in construction projects and the construction projects in Malaysia has no exemption from the problems of time overrun and cost overrun. In order to accomplish the successful completion of construction projects on specified time and within planned cost, there are various factors that should be given serious attention so that issues such as time and cost overrun can be addressed. This paper aims to construct a framework for the causes of time overrun and cost overrun in construction projects of Malaysia. Based on the relevant literature review, causative factors of time overrun and cost overrun in Malaysian construction projects are summarized and the theoretical frameworks of the causes of construction time overrun and cost overrun is constructed. The developed frameworks for construction time and cost overruns based on the existing literature will assist the construction practitioners to plan the efficient approaches for achieving successful completion of the projects.
A concept analysis of home and its meaning in the lives of three older adults.
Gillsjö, Catharina; Schwartz-Barcott, Donna
2011-03-01
To identify and define the concept of home and its meaning in the lives of three older women. For many older adults home is the centre of daily life and increasingly important as a place where health care is delivered. Yet, as a concept, home remains theoretically and empirically underdeveloped. The Hybrid Model of Concept Development was used to interface theoretical analysis and empirical observation with a focus on definition. A comprehensive, interdisciplinary literature review, semi-structured interviews with three older women and case and cross-case analysis were completed. Interviewees spoke of childhood, community, residential, church and heavenly homes. Feelings of comfort and security were associated with residential homes, peace and quiet with church homes, safety and pleasure with heavenly homes. The experience of home as being taken for granted, unselfconscious and unrecognized, became obvious when one woman tried to consciously establish a sense of being at home in her new residence. No single comprehensive and measurable definition was found. However, three major components were identified (place, relationship and experience) and used to define home as a place to which one is attached, feels comfortable and secure and has the experience of dwelling. Every day assumptions about the meaning of home and home as just another place where health care is provided are called into question. Increased awareness and dialogue is needed among health-care providers working with older adults in their homes. Future research needs to explore the impact of home care on the older adult's meaning of home and its potential impact on recovery. © 2010 Blackwell Publishing Ltd.
Kraft, Reuben H.; Mckee, Phillip Justin; Dagro, Amy M.; Grafton, Scott T.
2012-01-01
This article presents the integration of brain injury biomechanics and graph theoretical analysis of neuronal connections, or connectomics, to form a neurocomputational model that captures spatiotemporal characteristics of trauma. We relate localized mechanical brain damage predicted from biofidelic finite element simulations of the human head subjected to impact with degradation in the structural connectome for a single individual. The finite element model incorporates various length scales into the full head simulations by including anisotropic constitutive laws informed by diffusion tensor imaging. Coupling between the finite element analysis and network-based tools is established through experimentally-based cellular injury thresholds for white matter regions. Once edges are degraded, graph theoretical measures are computed on the “damaged” network. For a frontal impact, the simulations predict that the temporal and occipital regions undergo the most axonal strain and strain rate at short times (less than 24 hrs), which leads to cellular death initiation, which results in damage that shows dependence on angle of impact and underlying microstructure of brain tissue. The monotonic cellular death relationships predict a spatiotemporal change of structural damage. Interestingly, at 96 hrs post-impact, computations predict no network nodes were completely disconnected from the network, despite significant damage to network edges. At early times () network measures of global and local efficiency were degraded little; however, as time increased to 96 hrs the network properties were significantly reduced. In the future, this computational framework could help inform functional networks from physics-based structural brain biomechanics to obtain not only a biomechanics-based understanding of injury, but also neurophysiological insight. PMID:22915997
Ballano, Gema; Zanuy, David; Jiménez, Ana I.; Cativiela, Carlos; Nussinov, Ruth; Alemán, Carlos
2009-01-01
Here we study conformational stabilization induced in a β-helical nanostructure by position-specific mutations. The nanostructure is constructed through the self-assembly of the β-helical building block excised from E. coli galactoside acetyltransferase (PDB code 1krr, chain A; residues 131-165). The mutations involve substitutions by cyclic, conformationally constrained amino acids. Specifically, a complete structural analysis of the Pro-Xaa-Val sequence [with Xaa being Gly, Ac3c (1-aminocyclopropane-1-carboxylic acid) and Ac5c (1-aminocyclopentane-1-carboxylic acid)], corresponding to the 148-150 loop region in the wild-type (Gly) and mutated (Ac3c and Ac5c) 1krr, has been performed using Molecular Dynamics simulations and X-ray crystallography. Simulations have been performed for the wild-type and mutants of three different systems, namely the building block, the nanoconstruct and the isolated Pro-Xaa-Val tripeptide. Furthermore, the crystalline structures of five peptides of Pro-Xaa-Val or Xaa-Val sequences have been solved by X-ray diffraction analysis and compared with theoretical predictions. Both the theoretical and crystallographic studies indicate that the Pro-Acnc-Val sequences exhibit a high propensity to adopt turn-like conformations, and this propensity is little affected by the chemical environment. Overall, the results indicate that replacement of Gly149 by Ac3c or Ac5c significantly reduce the conformational flexibility of the target site enhancing the structural specificity of the building block and the nanoconstruct derived from the 1krr β-helical motif. PMID:18811190
NASA Astrophysics Data System (ADS)
Zhou, Qiaoying
Academic achievement and student participation in physics are lower than desired. Research has shown that there is a shortage of college students entering science and technology fields such as physics. E-learning may provide the technology-oriented Net Generation learner an option for taking courses such as physics in a course modality with which they are most comfortable thus garnering more participation and higher academic achievement. A quantitative ex-post facto study was performed to compare face-to-face and E-learning modalities on course completion and physics achievement for an entire introductory physics course. The theoretical framework for this study was based on the constructivist theory of education that implies a student-centered learning process. The sample consisted of 116 students enrolled in introductory physics courses at four 2-year community colleges in Texas. Course completion, SAT scores, Force Concept Inventory examination scores, as well as demographic information and employment information were examined. Linear and ordinal multiple regression analysis were used to determine if course modality is predictive of physics achievement while controlling for general scholastic aptitude, current employment, the presence of children in the home, and teacher evaluations. The results showed that students in the E-learning course performed better on the Force Concept Inventory than those in the traditional course both in the multiple regression analysis, beta = .61, p < .001, and in the ordinal regression analysis, Wald(1) = 18.83, p < .001. A chi-square test was used to determine if course completion rates differ between students in the two course modalities. The results showed no difference in course completion rates between students in the two course modalities, chi 2(1, n = 116) = 1.02, p = .312. It was concluded that students in an E-learning course modality had higher physics achievement but were no more likely to complete the introductory physics course than students were in a face-to-face modality. It was recommended that other colleges and universities should develop and test E-learning courses for introductory physics, that larger sample sizes should be used in future studies, and that additional outcome variables including the likelihood that a student chooses physics as a major or the likelihood that a student completes a physics degree should be examined.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hammond, P.; Khakoo, M.A.; McConkey, J.W.
1987-12-01
Measurements are presented representing a complete set of electron-photon polarization correlation parameters for the excitation of n /sup 1/P states of He at an incident energy of 80 eV and an electron scattering angle of 20/sup 0/. The data support the predictions of a recent theoretical paper that these parameters should exhibit little variation with n. However, disagreement in absolute values between experiment and theory indicates the need for additional theoretical input into the problem.
Modeling the History of Astronomy: Ptolemy, Copernicus, and Tycho
NASA Astrophysics Data System (ADS)
Timberlake, Todd K.
This paper describes a series of activities in which students investigate and use the Ptolemaic, Copernican, and Tychonic models of planetary motion. The activities guide students through using open source software to discover important observational facts, learn the necessary vocabulary, understand the fundamental properties of different theoretical models, and relate the theoretical models to observational data. After completing these activities students can make observations of a fictitious solar system and use those observations to construct models for that system.
Black hole state counting in loop quantum gravity: a number-theoretical approach.
Agulló, Iván; Barbero G, J Fernando; Díaz-Polo, Jacobo; Fernández-Borja, Enrique; Villaseñor, Eduardo J S
2008-05-30
We give an efficient method, combining number-theoretic and combinatorial ideas, to exactly compute black hole entropy in the framework of loop quantum gravity. Along the way we provide a complete characterization of the relevant sector of the spectrum of the area operator, including degeneracies, and explicitly determine the number of solutions to the projection constraint. We use a computer implementation of the proposed algorithm to confirm and extend previous results on the detailed structure of the black hole degeneracy spectrum.
Starke, Sandra D; Baber, Chris
2018-07-01
User interface (UI) design can affect the quality of decision making, where decisions based on digitally presented content are commonly informed by visually sampling information through eye movements. Analysis of the resulting scan patterns - the order in which people visually attend to different regions of interest (ROIs) - gives an insight into information foraging strategies. In this study, we quantified scan pattern characteristics for participants engaging with conceptually different user interface designs. Four interfaces were modified along two dimensions relating to effort in accessing information: data presentation (either alpha-numerical data or colour blocks), and information access time (all information sources readily available or sequential revealing of information required). The aim of the study was to investigate whether a) people develop repeatable scan patterns and b) different UI concepts affect information foraging and task performance. Thirty-two participants (eight for each UI concept) were given the task to correctly classify 100 credit card transactions as normal or fraudulent based on nine transaction attributes. Attributes varied in their usefulness of predicting the correct outcome. Conventional and more recent (network analysis- and bioinformatics-based) eye tracking metrics were used to quantify visual search. Empirical findings were evaluated in context of random data and possible accuracy for theoretical decision making strategies. Results showed short repeating sequence fragments within longer scan patterns across participants and conditions, comprising a systematic and a random search component. The UI design concept showing alpha-numerical data in full view resulted in most complete data foraging, while the design concept showing colour blocks in full view resulted in the fastest task completion time. Decision accuracy was not significantly affected by UI design. Theoretical calculations showed that the difference in achievable accuracy between very complex and simple decision making strategies was small. We conclude that goal-directed search of familiar information results in repeatable scan pattern fragments (often corresponding to information sources considered particularly important), but no repeatable complete scan pattern. The underlying concept of the UI affects how visual search is performed, and a decision making strategy develops. This should be taken in consideration when designing for applied domains. Copyright © 2018 Elsevier Ltd. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
MACKEY, T.C.
M&D Professional Services, Inc. (M&D) is under subcontract to Pacific Northwest National Laboratories (PNNL) to perform seismic analysis of the Hanford Site Double-Shell Tanks (DSTs) in support of a project entitled ''Double-Shell Tank (DSV Integrity Project-DST Thermal and Seismic Analyses)''. The overall scope of the project is to complete an up-to-date comprehensive analysis of record of the DST System at Hanford in support of Tri-Party Agreement Milestone M-48-14. The work described herein was performed in support of the seismic analysis of the DSTs. The thermal and operating loads analysis of the DSTs is documented in Rinker et al. (2004). Themore » overall seismic analysis of the DSTs is being performed with the general-purpose finite element code ANSYS. The overall model used for the seismic analysis of the DSTs includes the DST structure, the contained waste, and the surrounding soil. The seismic analysis of the DSTs must address the fluid-structure interaction behavior and sloshing response of the primary tank and contained liquid. ANSYS has demonstrated capabilities for structural analysis, but the capabilities and limitations of ANSYS to perform fluid-structure interaction are less well understood. The purpose of this study is to demonstrate the capabilities and investigate the limitations of ANSYS for performing a fluid-structure interaction analysis of the primary tank and contained waste. To this end, the ANSYS solutions are benchmarked against theoretical solutions appearing in BNL 1995, when such theoretical solutions exist. When theoretical solutions were not available, comparisons were made to theoretical solutions of similar problems and to the results from Dytran simulations. The capabilities and limitations of the finite element code Dytran for performing a fluid-structure interaction analysis of the primary tank and contained waste were explored in a parallel investigation (Abatt 2006). In conjunction with the results of the global ANSYS analysis reported in Carpenter et al. (2006), the results of the two investigations will be compared to help determine if a more refined sub-model of the primary tank is necessary to capture the important fluid-structure interaction effects in the tank and if so, how to best utilize a refined sub-model of the primary tank. Both rigid tank and flexible tank configurations were analyzed with ANSYS. The response parameters of interest are total hydrodynamic reaction forces, impulsive and convective mode frequencies, waste pressures, and slosh heights. To a limited extent: tank stresses are also reported. The results of this study demonstrate that the ANSYS model has the capability to adequately predict global responses such as frequencies and overall reaction forces. Thus, the model is suitable for predicting the global response of the tank and contained waste. On the other hand, while the ANSYS model is capable of adequately predicting waste pressures and primary tank stresses in a large portion of the waste tank, the model does not accurately capture the convective behavior of the waste near the free surface, nor did the model give accurate predictions of slosh heights. Based on the ability of the ANSYS benchmark model to accurately predict frequencies and global reaction forces and on the results presented in Abatt, et al. (2006), the global ANSYS model described in Carpenter et al. (2006) is sufficient for the seismic evaluation of all tank components except for local areas of the primary tank. Due to the limitations of the ANSYS model in predicting the convective response of the waste, the evaluation of primary tank stresses near the waste free surface should be supplemented by results from an ANSYS sub-model of the primary tank that incorporates pressures from theoretical solutions or from Dytran solutions. However, the primary tank is expected to have low demand to capacity ratios in the upper wall. Moreover, due to the less than desired mesh resolution in the primary tank knuckle of the global ANSYS model, the evaluation of the primary tank stresses in the lower knuckle should be supplemented by results from a more refined ANSYS sub-model of the primary tank that incorporates pressures from theoretical solutions or from Dytran solutions.« less
An isentropic compression-heated Ludweig tube transient wind tunnel
NASA Technical Reports Server (NTRS)
Magari, Patrick J.; Lagraff, John E.
1991-01-01
Theoretical development and experimental results show that the Ludweig tube with isentropic heating (LICH) transient wind tunnel described is a viable means of producing flow conditions that are suitable for a variety of experimental investigations. A complete analysis of the wave dynamics of the pump tube compression process is presented. The LICH tube operating conditions are very steady and run times are greater than those of other types of transient facilities such as shock tubes and gas tunnels. This facility is well suited for producing flow conditions that are dynamically similar to those found in a gas turbine, i.e., transonic Mach number, gas-to-wall temperature ratios of about 1.5, and Reynolds numbers greater than 10 to the 6th.
Bedewy, Dalia
2015-01-01
The development of a scale to measure perceived sources of academic stress among university students. Based on empirical evidence and recent literature review, we developed an 18-item scale to measure perceptions of academic stress and its sources. Experts (n = 12) participated in the content validation process of the instrument before it was administered to (n = 100) students. The developed instrument has internal consistency reliability of 0.7 (Cronbach’s alpha), there was evidence for content validity, and factor analysis resulted in four correlated and theoretically meaningful factors. We developed and tested a scale to measure academic stress and its sources. This scale takes 5 minutes to complete. PMID:28070363
Noise analysis in air-coupled PVDF ultrasonic sensors.
Fiorillo, A S
2000-01-01
In this paper we analyze the noise generated in a piezo-polymer based sensor for low frequency ultrasound in air. The sensor includes two curved PVDF transducers for medium and short range applications. A lumped RLC equivalent circuit was derived from the measurement of the transducer's electrical admittance, in air, by taking into account both mechanical and dielectric losses, which we suppose are the major sources of noise in similar devices. The electrical model was used to study and optimize the noise performance of a 61 kHz transducer and to simulate the electrical behavior of the complete transmitter-receiver system. The validity of the overall electrical model with low noise was confirmed after verifying, with Pspice, agreement of the practical and theoretical results.
Turing instability in reaction-diffusion models on complex networks
NASA Astrophysics Data System (ADS)
Ide, Yusuke; Izuhara, Hirofumi; Machida, Takuya
2016-09-01
In this paper, the Turing instability in reaction-diffusion models defined on complex networks is studied. Here, we focus on three types of models which generate complex networks, i.e. the Erdős-Rényi, the Watts-Strogatz, and the threshold network models. From analysis of the Laplacian matrices of graphs generated by these models, we numerically reveal that stable and unstable regions of a homogeneous steady state on the parameter space of two diffusion coefficients completely differ, depending on the network architecture. In addition, we theoretically discuss the stable and unstable regions in the cases of regular enhanced ring lattices which include regular circles, and networks generated by the threshold network model when the number of vertices is large enough.
The Effect of the Density Ratio on the Nonlinear Dynamics of the Unstable Fluid Interface
NASA Technical Reports Server (NTRS)
Abarzhi, S. I.
2003-01-01
Here we report multiple harmonic theoretical solutions for a complete system of conservation laws, which describe the large-scale coherent dynamics in RTI and RMI for fluids with a finite density ratio in the general three-dimensional case. The analysis yields new properties of the bubble front dynamics. In either RTI or RMI, the obtained dependencies of the bubble velocity and curvature on the density ratio differ qualitatively and quantitatively from those suggested by the models of Sharp (1984), Oron et al. (2001), and Goncharov (2002). We show explicitly that these models violate the conservation laws. For the first time, our theory reveals an important qualitative distinction between the dynamics of the RT and RM bubbles.
Observation of airplane flow fields by natural condensation effects
NASA Technical Reports Server (NTRS)
Campbell, James F.; Chambers, Joseph R.; Rumsey, Christopher L.
1988-01-01
In-flight condensation patterns can illustrate a variety of airplane flow fields, such as attached and separated flows, vortex flows, and expansion and shock waves. These patterns are a unique source of flow visualization that has not been utilized previously. Condensation patterns at full-scale Reynolds number can provide useful information for researchers experimenting in subscale tunnels. It is also shown that computed values of relative humidity in the local flow field provide an inexpensive way to analyze the qualitative features of the condensation pattern, although a more complete theoretical modeling is necessary to obtain details of the condensation process. Furthermore, the analysis revealed that relative humidity is more sensitive to changes in local static temperature than to changes in pressure.
Modeling of knowledge transmission by considering the level of forgetfulness in complex networks
NASA Astrophysics Data System (ADS)
Cao, Bin; Han, Shui-hua; Jin, Zhen
2016-06-01
In this study, we establish a general model by considering the level of forgetfulness during knowledge transmission in complex networks, where the level of forgetfulness depends mainly on the number in a crowd who possess knowledge, while the saturated incidence is also considered. In theory, we analyze the stability of the equilibrium points and the transmission threshold R0 is also given. If R0 > 1, then knowledge can be transmitted, but if not, it will become completely extinct. In addition, we performed some numerical simulations to verify the reasonability of the theoretical analysis. The results of the simulations also suggest that the proportion of the crowd with knowledge will be increased under a better cultural atmosphere.
A note on effects of rational bubble on portfolios
NASA Astrophysics Data System (ADS)
Wang, Chan; Nie, Pu-yan
2018-02-01
In general, demand increases in wealth and decreases in price in microeconomics. We thereby propose a completely different perspective. By establishing expected utility function of investors, this article introduces one rational bubble asset and one bubble free asset in portfolios and focuses on the effects of bubble on investment portfolios from wealth and price perspectives. All conclusions are obtained by theoretical analysis with microeconomics theory. We argue that inferior goods and Giffen behavior can occur for the bubble free asset in microeconomic fields. The results can help investors to recognize bubble assets and bubble free assets more scientifically. Both bubble and bubble free assets can be inferior goods under some conditions, so we cannot to say which asset better than the other one absolutely.
Super-resolving random-Gaussian apodized photon sieve.
Sabatyan, Arash; Roshaninejad, Parisa
2012-09-10
A novel apodized photon sieve is presented in which random dense Gaussian distribution is implemented to modulate the pinhole density in each zone. The random distribution in dense Gaussian distribution causes intrazone discontinuities. Also, the dense Gaussian distribution generates a substantial number of pinholes in order to form a large degree of overlap between the holes in a few innermost zones of the photon sieve; thereby, clear zones are formed. The role of the discontinuities on the focusing properties of the photon sieve is examined as well. Analysis shows that secondary maxima have evidently been suppressed, transmission has increased enormously, and the central maxima width is approximately unchanged in comparison to the dense Gaussian distribution. Theoretical results have been completely verified by experiment.
Oesterling, Sven; Schalk, Oliver; Geng, Ting; Thomas, Richard D; Hansson, Tony; de Vivie-Riedle, Regina
2017-01-18
For the series furan, furfural and β-furfural we investigated the effect of substituents and their positioning on the photoinduced relaxation dynamics in a combined theoretical and experimental approach. Using time resolved photoelectron spectroscopy with a high intensity probe pulse, we can, for the first time, follow the whole deactivation process of furan through a two photon probe signal. Using the extended 2-electron 2-orbital model [Nenov et al., J. Chem. Phys., 2011, 135, 034304] we explain the formation of one central conical intersection and predict the influence of the aldehyde group of the derivatives on its geometry. This, as well as the relaxation mechanisms from photoexcitation to the final outcome was investigated using a variety of theoretical methods. Complete active space self consistent field was used for on-the-fly calculations while complete active space perturbation theory and coupled cluster theory were used to accurately describe critical configurations. Experiment and theory show the relaxation dynamics of furfural and β-furfural to be slowed down, and together they disclose an additional deactivation pathway, which is attributed to the n O lonepair state introduced with the aldehyde group.
Several foundational and information theoretic implications of Bell’s theorem
NASA Astrophysics Data System (ADS)
Kar, Guruprasad; Banik, Manik
2016-08-01
In 1935, Albert Einstein and two colleagues, Boris Podolsky and Nathan Rosen (EPR) developed a thought experiment to demonstrate what they felt was a lack of completeness in quantum mechanics (QM). EPR also postulated the existence of more fundamental theory where physical reality of any system would be completely described by the variables/states of that fundamental theory. This variable is commonly called hidden variable and the theory is called hidden variable theory (HVT). In 1964, John Bell proposed an empirically verifiable criterion to test for the existence of these HVTs. He derived an inequality, which must be satisfied by any theory that fulfill the conditions of locality and reality. He also showed that QM, as it violates this inequality, is incompatible with any local-realistic theory. Later it has been shown that Bell’s inequality (BI) can be derived from different set of assumptions and it also find applications in useful information theoretic protocols. In this review, we will discuss various foundational as well as information theoretic implications of BI. We will also discuss about some restricted nonlocal feature of quantum nonlocality and elaborate the role of Uncertainty principle and Complementarity principle in explaining this feature.
Finite Element Analysis of Walking Beam of a New Compound Adjustment Balance Pumping Unit
NASA Astrophysics Data System (ADS)
Wu, Jufei; Wang, Qian; Han, Yunfei
2017-12-01
In this paper, taking the designer of the new compound balance pumping unit beam as our research target, the three-dimensional model is established by Solid Works, the load and the constraint are determined. ANSYS Workbench is used to analyze the tail and the whole of the beam, the stress and deformation are obtained to meet the strength requirements. The finite element simulation and theoretical calculation of the moment of the center axis beam are carried out. The finite element simulation results are compared with the calculated results of the theoretical mechanics model to verify the correctness of the theoretical calculation. Finally, the finite element analysis is consistent with the theoretical calculation results. The theoretical calculation results are preferable, and the bending moment value provides the theoretical reference for the follow-up optimization and research design.
Huijg, Johanna M; Dusseldorp, Elise; Gebhardt, Winifred A; Verheijden, Marieke W; van der Zouwe, Nicolette; Middelkoop, Barend J C; Duijzer, Geerke; Crone, Mathilde R
2015-04-01
Physical therapists play an important role in the promotion of physical activity (PA) and the effectiveness of PA interventions. However, little is known about the extent to which they implement PA interventions following the intervention protocol and about the factors influencing their implementation behaviors. The study objective was to investigate physical therapists' implementation fidelity regarding PA interventions, including completeness and quality of delivery, and influencing factors with a Theoretical Domains Framework-based questionnaire. The study was based on a cross-sectional design. A total of 268 physical therapists completed the Determinants of Implementation Behavior Questionnaire. Questions about completeness and quality of delivery were based on components and tasks of PA interventions as described by the Royal Dutch Society for Physical Therapy. Multilevel regression analyses were used to identify factors associated with completeness and quality of delivery. High implementation fidelity was found for the physical therapists, with higher scores for completeness of delivery than for quality of delivery. Physical therapists' knowledge, skills, beliefs about capabilities and consequences, positive emotions, behavioral regulation, and the automaticity of PA intervention delivery were the most important predictors of implementation fidelity. Together, the Theoretical Domains Framework accounted for 23% of the variance in both total completeness and total quality scores. The cross-sectional design precluded the determination of causal relationships. Also, the use of a self-report measure to assess implementation fidelity could have led to socially desirable responses, possibly resulting in more favorable ratings for completeness and quality. This study enhances the understanding of how physical therapists implement PA interventions and which factors influence their behaviors. Knowledge about these factors may assist in the development of strategies to improve physical therapists' implementation behaviors. © 2015 American Physical Therapy Association.
Yilmaz Soylu, Meryem; Zeleny, Mary G.; Zhao, Ruomeng; Bruning, Roger H.; Dempsey, Michael S.; Kauffman, Douglas F.
2017-01-01
The two studies reported here explored the factor structure of the newly constructed Writing Achievement Goal Scale (WAGS), and examined relationships among secondary students' writing achievement goals, writing self-efficacy, affect for writing, and writing achievement. In the first study, 697 middle school students completed the WAGS. A confirmatory factor analysis revealed a good fit for this data with a three-factor model that corresponds with mastery, performance approach, and performance avoidance goals. The results of Study 1 were an indication for the researchers to move forward with Study 2, which included 563 high school students. The secondary students completed the WAGS, as well as the Self-efficacy for Writing Scale, and the Liking Writing Scale. Students also self-reported grades for writing and for language arts courses. Approximately 6 weeks later, students completed a statewide writing assessment. We tested a theoretical model representing relationships among Study 2 variables using structural equation modeling including students' responses to the study scales and students' scores on the statewide assessment. Results from Study 2 revealed a good fit between a model depicting proposed relationships among the constructs and the data. Findings are discussed relative to achievement goal theory and writing. PMID:28878707
Measuring motivation and volition of nursing students in nontraditional learning environments.
Nagelsmith, Laurie; Bryer, Jason; Yan, Zheng
2012-01-01
The purpose of this study was to identify the best fitting model to represent interrelationships between motivation, volition, and academic success for adult nursing students learning in nontraditional environments. Participants (N=297) completed a survey that incorporated two measures: the Motivated Strategies for Learning Questionnaire (MSLQ) and the academic volitional strategies inventory (AVSI) as well as demographic information. Exploratory factor analysis (EFA), confirmatory factor analysis (CFA), and structural equation modeling (SEM) were used for data analysis. In phase 1, EFA resulted in factors that generally aligned with previous theoretical factors as defined by the psychometrics used. In Phase 2 of the analysis, CFA validated the use of predefined factor structures. In Phase 3, SEM analysis revealed that motivation has a larger effect on grade point average (GPA; beta = .28, p < .01) than volition (beta = .15, p < .05). The covariance between motivation and volition (r = .42, p < .01) was also found to be significant. These results suggest that there is a significant relationship among motivation, volition, and academic success for adult learners studying in nontraditional learning environments. These findings are consistent with and elaborate the relationship between motivation and volition with a population and setting underrepresented in the research.
NASA Astrophysics Data System (ADS)
Hellwagner, Johannes; Sharma, Kshama; Tan, Kong Ooi; Wittmann, Johannes J.; Meier, Beat H.; Madhu, P. K.; Ernst, Matthias
2017-06-01
Pulse imperfections like pulse transients and radio-frequency field maladjustment or inhomogeneity are the main sources of performance degradation and limited reproducibility in solid-state nuclear magnetic resonance experiments. We quantitatively analyze the influence of such imperfections on the performance of symmetry-based pulse sequences and describe how they can be compensated. Based on a triple-mode Floquet analysis, we develop a theoretical description of symmetry-based dipolar recoupling sequences, in particular, R2 6411, calculating first- and second-order effective Hamiltonians using real pulse shapes. We discuss the various origins of effective fields, namely, pulse transients, deviation from the ideal flip angle, and fictitious fields, and develop strategies to counteract them for the restoration of full transfer efficiency. We compare experimental applications of transient-compensated pulses and an asynchronous implementation of the sequence to a supercycle, SR26, which is known to be efficient in compensating higher-order error terms. We are able to show the superiority of R26 compared to the supercycle, SR26, given the ability to reduce experimental error on the pulse sequence by pulse-transient compensation and a complete theoretical understanding of the sequence.
Vibration analysis on compact car shock absorber
NASA Astrophysics Data System (ADS)
Tan, W. H.; Cheah, J. X.; Lam, C. K.; Lim, E. A.; Chuah, H. G.; Khor, C. Y.
2017-10-01
Shock absorber is a part of the suspension system which provides comfort experience while driving. Resonance, a phenomenon where forced frequency is coinciding with the natural frequency has significant effect on the shock absorber itself. Thus, in this study, natural frequencies of the shock absorber in a 2 degree-of-freedom system were investigated using Wolfram Mathematica 11, CATIA, and ANSYS. Both theoretical and simulation study how will the resonance affect the car shock absorber. The parametric study on the performance of shock absorber also had been conducted. It is found that the failure tends to occur on coil sprung of the shock absorber before the body of the shock absorber is fail. From mathematical modelling, it can also be seen that higher vibration level occurred on un-sprung mass compare to spring mass. This is due to the weight of sprung mass which could stabilize as compared with the weight of un-sprung mass. Besides that, two natural frequencies had been obtained which are 1.0 Hz and 9.1 Hz for sprung mass and un-sprung mass respectively where the acceleration is recorded as maximum. In conclusion, ANSYS can be used to validate with theoretical results with complete model in order to match with mathematical modelling.
Dispersionless Manipulation of Reflected Acoustic Wavefront by Subwavelength Corrugated Surface
Zhu, Yi-Fan; Zou, Xin-Ye; Li, Rui-Qi; Jiang, Xue; Tu, Juan; Liang, Bin; Cheng, Jian-Chun
2015-01-01
Free controls of optic/acoustic waves for bending, focusing or steering the energy of wavefronts are highly desirable in many practical scenarios. However, the dispersive nature of the existing metamaterials/metasurfaces for wavefront manipulation necessarily results in limited bandwidth. Here, we propose the concept of dispersionless wavefront manipulation and report a theoretical, numerical and experimental work on the design of a reflective surface capable of controlling the acoustic wavefront arbitrarily without bandwidth limitation. Analytical analysis predicts the possibility to completely eliminate the frequency dependence with a specific gradient surface which can be implemented by designing a subwavelength corrugated surface. Experimental and numerical results, well consistent with the theoretical predictions, have validated the proposed scheme by demonstrating a distinct phenomenon of extraordinary acoustic reflection within an ultra-broad band. For acquiring a deeper insight into the underlying physics, a simple physical model is developed which helps to interpret this extraordinary phenomenon and predict the upper cutoff frequency precisely. Generations of planar focusing and non-diffractive beam have also been exemplified. With the dispersionless wave-steering capability and deep discrete resolution, our designed structure may open new avenue to fully steer classical waves and offer design possibilities for broadband optical/acoustical devices. PMID:26077772
Cosmological implications of a large complete quasar sample.
Segal, I E; Nicoll, J F
1998-04-28
Objective and reproducible determinations of the probabilistic significance levels of the deviations between theoretical cosmological prediction and direct model-independent observation are made for the Large Bright Quasar Sample [Foltz, C., Chaffee, F. H., Hewett, P. C., MacAlpine, G. M., Turnshek, D. A., et al. (1987) Astron. J. 94, 1423-1460]. The Expanding Universe model as represented by the Friedman-Lemaitre cosmology with parameters qo = 0, Lambda = 0 denoted as C1 and chronometric cosmology (no relevant adjustable parameters) denoted as C2 are the cosmologies considered. The mean and the dispersion of the apparent magnitudes and the slope of the apparent magnitude-redshift relation are the directly observed statistics predicted. The C1 predictions of these cosmology-independent quantities are deviant by as much as 11sigma from direct observation; none of the C2 predictions deviate by >2sigma. The C1 deviations may be reconciled with theory by the hypothesis of quasar "evolution," which, however, appears incapable of being substantiated through direct observation. The excellent quantitative agreement of the C1 deviations with those predicted by C2 without adjustable parameters for the results of analysis predicated on C1 indicates that the evolution hypothesis may well be a theoretical artifact.
Computational crystallization.
Altan, Irem; Charbonneau, Patrick; Snell, Edward H
2016-07-15
Crystallization is a key step in macromolecular structure determination by crystallography. While a robust theoretical treatment of the process is available, due to the complexity of the system, the experimental process is still largely one of trial and error. In this article, efforts in the field are discussed together with a theoretical underpinning using a solubility phase diagram. Prior knowledge has been used to develop tools that computationally predict the crystallization outcome and define mutational approaches that enhance the likelihood of crystallization. For the most part these tools are based on binary outcomes (crystal or no crystal), and the full information contained in an assembly of crystallization screening experiments is lost. The potential of this additional information is illustrated by examples where new biological knowledge can be obtained and where a target can be sub-categorized to predict which class of reagents provides the crystallization driving force. Computational analysis of crystallization requires complete and correctly formatted data. While massive crystallization screening efforts are under way, the data available from many of these studies are sparse. The potential for this data and the steps needed to realize this potential are discussed. Copyright © 2016 Elsevier Inc. All rights reserved.
Optimization Techniques for Analysis of Biological and Social Networks
2012-03-28
analyzing a new metaheuristic technique, variable objective search. 3. Experimentation and application: Implement the proposed algorithms , test and fine...alternative mathematical programming formulations, their theoretical analysis, the development of exact algorithms , and heuristics. Originally, clusters...systematic fashion under a unifying theoretical and algorithmic framework. Optimization, Complex Networks, Social Network Analysis, Computational
Analysis of rosen piezoelectric transformers with a varying cross-section.
Xue, H; Yang, J; Hu, Y
2008-07-01
We study the effects of a varying cross-section on the performance of Rosen piezoelectric transformers operating with length extensional modes of rods. A theoretical analysis is performed using an extended version of a one-dimensional model developed in a previous paper. Numerical results based on the theoretical analysis are presented.
Millard, Pierre; Massou, Stéphane; Portais, Jean-Charles; Létisse, Fabien
2014-10-21
Mass spectrometry (MS) is widely used for isotopic studies of metabolism in which detailed information about biochemical processes is obtained from the analysis of isotope incorporation into metabolites. The biological value of such experiments is dependent on the accuracy of the isotopic measurements. Using MS, isotopologue distributions are measured from the quantitative analysis of isotopic clusters. These measurements are prone to various biases, which can occur during the experimental workflow and/or MS analysis. The lack of relevant standards limits investigations of the quality of the measured isotopologue distributions. To meet that need, we developed a complete theoretical and experimental framework for the biological production of metabolites with fully controlled and predictable labeling patterns. This strategy is valid for different isotopes and different types of metabolisms and organisms, and was applied to two model microorganisms, Pichia augusta and Escherichia coli, cultivated on (13)C-labeled methanol and acetate as sole carbon source, respectively. The isotopic composition of the substrates was designed to obtain samples in which the isotopologue distribution of all the metabolites should give the binomial coefficients found in Pascal's triangle. The strategy was validated on a liquid chromatography-tandem mass spectrometry (LC-MS/MS) platform by quantifying the complete isotopologue distributions of different intracellular metabolites, which were in close agreement with predictions. This strategy can be used to evaluate entire experimental workflows (from sampling to data processing) or different analytical platforms in the context of isotope labeling experiments.
Validation of the quality of life in childhood epilepsy questionnaire in American epilepsy patients.
Sabaz, Mark; Lawson, John A; Cairns, David R; Duchowny, Michael S; Resnick, Trevor J; Dean, Patricia M; Bye, Ann M E
2003-12-01
The aim of this study was to adapt the Australian Quality of Life in Childhood Epilepsy Questionnaire (QOLCE) and determine its psychometric properties in a North American population. Participants were North American families with children diagnosed with epilepsy. Parents were asked to complete the American QOLCE (USQOLCE) and the Child Health Questionnaire (CHQ). Seventy-one families completed the USQOLCE. The internal consistency reliability of the subscales was good. USQOLCE subscales correlated highly with theoretically similar subscales contained in the CHQ. Theoretically dissimilar subscales on the two instruments did not correlate as well. USQOLCE correlated significantly with a parental rating of seizure severity and an independent measure of degree of postoperative seizure control. This study demonstrated that the USQOLCE is suitable for a North American population with evidence of its reliability and validity including its sensitivity to seizure burden.
Towards a mathematical theory of meaningful communication
NASA Astrophysics Data System (ADS)
Corominas-Murtra, Bernat; Fortuny, Jordi; Solé, Ricard V.
2014-04-01
Meaning has been left outside most theoretical approaches to information in biology. Functional responses based on an appropriate interpretation of signals have been replaced by a probabilistic description of correlations between emitted and received symbols. This assumption leads to potential paradoxes, such as the presence of a maximum information associated to a channel that creates completely wrong interpretations of the signals. Game-theoretic models of language evolution and other studies considering embodied communicating agents show that the correct (meaningful) match resulting from agent-agent exchanges is always achieved and natural systems obviously solve the problem correctly. Inspired by the concept of duality of the communicative sign stated by the swiss linguist Ferdinand de Saussure, here we present a complete description of the minimal system necessary to measure the amount of information that is consistently decoded. Several consequences of our developments are investigated, such as the uselessness of a certain amount of information properly transmitted for communication among autonomous agents.
Altschuler, Ted S.; Molholm, Sophie; Butler, John S.; Mercier, Manuel R.; Brandwein, Alice B.; Foxe, John J.
2014-01-01
The adult human visual system can efficiently fill-in missing object boundaries when low-level information from the retina is incomplete, but little is known about how these processes develop across childhood. A decade of visual-evoked potential (VEP) studies has produced a theoretical model identifying distinct phases of contour completion in adults. The first, termed a perceptual phase, occurs from approximately 100-200 ms and is associated with automatic boundary completion. The second is termed a conceptual phase occurring between 230-400 ms. The latter has been associated with the analysis of ambiguous objects which seem to require more effort to complete. The electrophysiological markers of these phases have both been localized to the lateral occipital complex, a cluster of ventral visual stream brain regions associated with object-processing. We presented Kanizsa-type illusory contour stimuli, often used for exploring contour completion processes, to neurotypical persons ages 6-31 (N= 63), while parametrically varying the spatial extent of these induced contours, in order to better understand how filling-in processes develop across childhood and adolescence. Our results suggest that, while adults complete contour boundaries in a single discrete period during the automatic perceptual phase, children display an immature response pattern - engaging in more protracted processing across both timeframes and appearing to recruit more widely distributed regions which resemble those evoked during adult processing of higher-order ambiguous figures. However, children older than 5 years of age were remarkably like adults in that the effects of contour processing were invariant to manipulation of contour extent. PMID:24365674
2010-09-01
reports. This project is aimed at a combined theoretical and experimental analysis of adhesives. The theoretical part of it is based on usage of... Theoretical Difficulties in the Thermodynamics of Heterogeneous Systems and Fracture 3 3. Thermodynamic Model of Velcro 7 3.1 Derivation of Equations 5 and 6...mechanochemical systems). Among those are fracture of solids , analysis of solid explosives , chemical reactions in solids , environmental stress corrosion and
NASA Astrophysics Data System (ADS)
Hunter, Rachel; Ernst, David; Vastola, John; Austin, Noah
In the 1980's and 90's a series of experiments were conducted to search for evidence of neutrino oscillations. Data was collected on five of the six independent fundamental parameters relating to oscillation rates. The data was then used to produce an exclusion region plot for values of the parameters. However, it was discovered that the experiments were not analyzed correctly and there are large gaps between theoretical and experimental data. A fourth type of neutrino could be to blame for these gaps. The goal of this research project is to find evidence for or against a fourth type of neutrino by a reanalysis of the old experiments. This part of the project attempts to reproduce the exclusion region plots for data taken at Rovno Nuclear Power Station in order to validate a model of the original analysis. Thus far the reproduction of their exclusion region is close, but not a complete success. Further work on the coding program will need to be completed in order to proceed with the next step in the reanalysis procedure. National Science Foundation Grant #1263045.
Ultrawide bandgap pentamode metamaterials with an asymmetric double-cone outside profile
NASA Astrophysics Data System (ADS)
Chu, Yangyang; Li, Yucheng; Cai, Chengxin; Liu, Guangshuan; Wang, Zhaohong; Xu, Zhuo
2018-03-01
The band-gap characteristic is an important feature of acoustic metamaterials, which has important theoretical and practical significance in acoustic devices. Pentamode metamaterials (PMs) with phonon band-gap characteristics based on an asymmetric double-cone outside profile are presented and studied in this paper. The phonon band structures of these PMs are calculated by using the finite element method. In addition to the single-mode band-gaps, the complete 3D band-gaps are also obtained by changing the outside profile of the double-cone. Moreover, by adjusting the outside profile and the diameter of the double-cone to reduce the symmetry of the structure, the complete 3D band-gap can be widened. Further parametric analysis is presented to investigate the effect of geometrical parameters on the phonon band-gap property, the numerical simulations show that the maximum relative bandwidth is expanded by 15.14 times through reducing the symmetry of the structure. This study provides a possible way for PMs to control elastic wave propagation in the field of depressing vibration and noise, acoustic filtering and acoustic cloaking.
BETA (Bitter Electromagnet Testing Apparatus)
NASA Astrophysics Data System (ADS)
Bates, Evan M.; Birmingham, William J.; Rivera, William F.; Romero-Talamas, Carlos A.
2017-10-01
The Bitter Electromagnet Testing Apparatus (BETA) is a 1-Tesla (T) prototype of the 10-T Adjustable Long Pulse High-Field Apparatus (ALPHA). These water-cooled resistive magnets use high DC currents to produce strong uniform magnetic fields. Presented here is the successful completion of the BETA project and experimental results validating analytical magnet designing methods developed at the Dusty Plasma Laboratory (DPL). BETA's final design specifications will be highlighted which include electromagnetic, thermal and stress analyses. The magnet core design will be explained which include: Bitter Arcs, helix starters, and clamping annuli. The final version of the magnet's vessel and cooling system are also presented, as well as the electrical system of BETA, which is composed of a unique solid-state breaker circuit. Experimental results presented will show the operation of BETA at 1 T. The results are compared to both analytical design methods and finite element analysis calculations. We also explore the steady state maximums and theoretical limits of BETA's design. The completion of BETA validates the design and manufacturing techniques that will be used in the succeeding magnet, ALPHA.
Hua, Guofen; Chen, Qiuwen; Kong, Jun; Li, Man
2017-08-01
Clogging is the most significant challenge limiting the application of constructed wetlands. Application of a forced resting period is a practical way to relieve clogging, particularly bioclogging. To reveal the alleviation mechanisms behind such a resting operation, evapotranspiration and oxygen flux were studied during a resting period in a laboratory vertical-flow constructed wetland model through physical simulation and numerical model analysis. In addition, the optimum theoretical resting duration was determined based on the time required for oxygen to completely fill the pores, i.e., formation of a sufficiently thick and completely dry layer. The results indicated that (1) evapotranspiration was not the key factor, but was a driving force in the alleviation of bioclogging; (2) the rate of oxygen diffusion into the pores was sufficient to oxidize and disperse the flocculant biofilm, which was essential to alleviate bioclogging. This study provides important insights into understanding how clogging/bioclogging can be alleviated in vertical-flow constructed wetlands. Graphical abstract Evapotranspiration versus oxygen intrusion in alleviating bioclogging in vertical flow constructed wetlands.
High pressure cosmochemistry applied to major planetary interiors: Experimental studies
NASA Technical Reports Server (NTRS)
Nicol, M. F.; Johnson, M.; Koumvakalis, A. S.
1984-01-01
Progress is reported on a project to determine the properties and boundaries of high pressure phases of the H2-He-H2O-NH3-CH4 system that are needed to constrain theoretical models of the interiors of the major planets. This project is one of the first attempts to measure phase equilibria in binary fluid-solid systems in diamond anvil cells. Vibrational spectroscopy, direct visual observations, and X-ray diffraction crystallography of materials confined in externally heated cells are the primary experimental probes. Adiabats of these materials are also measured in order to constrain models of heat flow in these bodies and to detect phase transitions by thermal anomalies. Initial efforts involve the NH3-H2O binary. This system is especially relevant to models for surface reconstruction of the icy satellites of Jupiter and Saturn. Thermal analysis experiments were completed for the P-X space, p4GPa:0 or = 0.50, near room temperature. The cryostat, sample handling equipment, and optics needed to extend the optical P-T-X work below room temperature was completed.
Attrill, Stacie; Gunn, Simon
2010-04-01
There has been limited research investigating the conceptual development of rehabilitation in speech-language pathology (SLP) students. The aim of this study was to describe SLP students' understanding of rehabilitation following completion of a clinical practicum in a rehabilitation setting. This study was conducted using a qualitative approach according to grounded theory methodology. Semi-structured interviews were conducted with 10 SLP students who had completed a practicum in a rehabilitation setting. Interview data analysis revealed the emergence of five axial categories. Clients becoming teachers was identified as the core category, as the notion that clients were fundamental to students' understanding of rehabilitation occurred reliably throughout the data and related to all other categories. A theoretical model was proposed that demonstrated successive levels of support to students in the acquisition of their understanding of rehabilitation on practicum. Students' understanding of rehabilitation was derived from client-related interactions and factors experienced on practicum in rehabilitation settings. Rehabilitation practicum provided students with a rich and complex learning environment that may facilitate the development of the "core skills" identified for rehabilitation practice.
Sweet, Shane N; Fortier, Michelle S; Guérin, Eva; Tulloch, Heather; Sigal, Ronald J; Kenny, Glen P; Reid, Robert D
2009-08-01
This study was set out to test if autonomous motivation mediated the relationship between self-efficacy and 12-month physical activity (PA) in adults with type 2 diabetes involved in a randomized exercise trial. Participants (n = 234) completed questionnaires measuring barrier self-efficacy at 3 months, autonomous motivation at 6 months, and PA at 12 months. A mediational analysis of longitudinal data revealed that autonomous motivation mediated the relationship between barrier-self-efficacy and PA. High barrier self-efficacy can therefore help predict 12-month PA in adults with type 2 diabetes, although this effect is attenuated by autonomous motivation. Hence, participating in PA for autonomous reasons such as by choice and/or for fun further explains PA at 12 months in this population. Results of this study extend our understanding of the motivational constructs involved in PA in the maintenance phase. This study has important theoretical implications in that it helps to organize and consolidate well-known correlates of PA by proposing a temporal relationship between them that could be tailored in interventions.
Five ways of being "theoretical": applications to provider-patient communication research.
Hall, Judith A; Schmid Mast, Marianne
2009-03-01
Analyzes the term "theoretical" as it applies to the area of provider-patient communication research, in order to understand better at a conceptual level what the term may mean for authors and critics. Based on literature on provider-patient communication. Offers, and discusses, five definitions of the term "theoretical" as it applies to empirical research and its exposition: (1) grounding, (2) referencing, (3) design and analysis, (4) interpretation, and (5) impact. Each of these definitions embodies a different standard for evaluating the theoretical aspects of research. Although it is often said that research on provider-patient communication is not "theoretical" enough, the term is ambiguous and often applied vaguely. A multidimensional analysis reveals that there are several distinct ways in which empirical research can be strong or weak theoretically. Researchers, educators, editors, and reviewers could use the "Five Ways" framework to appraise the theory-relevant strengths and weaknesses of empirical research and its exposition.
A Spatial Analysis and Game Theoretical Approach Over the Disputed Islands in the Aegean Sea
2016-06-01
NAVAL POSTGRADUATE SCHOOL MONTEREY, CALIFORNIA THESIS Approved for public release; distribution is unlimited A SPATIAL ANALYSIS ...REPORT TYPE AND DATES COVERED Master’s thesis 4. TITLE AND SUBTITLE A SPATIAL ANALYSIS AND GAME THEORETICAL APPROACH OVER THE DISPUTED ISLANDS...including perimeter, area, population, distance to Greece, distance to Turkey, and territorial water area. After applying spatial analysis to two
Philosophical Foundations for Curriculum Decision: A Reflective Analysis
ERIC Educational Resources Information Center
Belbase, Shashidhar
2011-01-01
This paper discusses the author's curriculum experiences under different philosophical, epistemological and theoretical backdrops. The analysis of different perspectives bridges epistemological and philosophical/theoretical lenses to my understanding of curriculum and different curricular decisions. This praxeological experience as a student and…
Evanescent waves and deaf bands in sonic crystals
NASA Astrophysics Data System (ADS)
Romero-García, V.; Garcia-Raffi, L. M.; Sánchez-Pérez, J. V.
2011-12-01
The properties of sonic crystals (SC) are theoretically investigated in this work by solving the inverse problem k(ω) using the extended plane wave expansion (EPWE). The solution of the resulting eigenvalue problem gives the complex band structure which takes into account both the propagating and the evanescent modes. In this work we show the complete mathematical formulation of the EPWE for SC and the supercell approximation for its use in both a complete SC and a SC with defects. As an example we show a novel interpretation of the deaf bands in a complete SC in good agreement with multiple scattering simulations.
Eiser, C; Vance, Y H; Seamark, D
2000-11-01
To report the development and psychometric properties of a generic computer-delivered measure of quality of life (QoL) suitable for children aged 6-12 years: the Exqol. The theoretical model adopted is based on an assumption that poorer QoL is the result of discrepancies between an individual's actual ('like me') and ideal self ('how I would like to be'). The Exqol consists of 12 pictures, each of which is rated twice; first in terms of 'like me' and second as 'I would like to be'. The Exqol is delivered using a Macintosh Powerbook and takes approximately 20 min to complete. Data are reported for 58 children with asthma (Mage = 8.95 years) and 69 healthy children (Mage = 749 years). In order to determine validity of the Exqol, children with asthma also completed the Childhood Asthma Questionnaire (CAQ) and their mothers completed a measure of child vulnerability and caregiver QoL. Higher discrepancies were found for children with asthma compared with healthy children (P < 0.05). For children with asthma, significant correlations were found between discrepancy scores and two of the four subscales of the CAQ. Children who rated their asthma to be more severe also had higher discrepancy scores (P < 0.05). The Exqol has acceptable internal reliability and validity and distinguishes between children with asthma and healthy children. These data provide preliminary support for the theoretical assumption that QoL reflects perceived discrepancies between an individual's actual and ideal self. Methodological refinements to the Exqol are suggested.
No more freeways : urban land use-transportation dynamics without freeway capacity expansion
DOT National Transportation Integrated Search
2011-01-01
Observations of the various limitations of freeway capacity expansion have led to a provocative planning and policy question What if we : completely stop building additional freeway capacity. From a theoretical perspective, as a freeway transport...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Haraldsdóttir, Hulda S.; Fleming, Ronan M. T.
Conserved moieties are groups of atoms that remain intact in all reactions of a metabolic network. Identification of conserved moieties gives insight into the structure and function of metabolic networks and facilitates metabolic modelling. All moiety conservation relations can be represented as nonnegative integer vectors in the left null space of the stoichiometric matrix corresponding to a biochemical network. Algorithms exist to compute such vectors based only on reaction stoichiometry but their computational complexity has limited their application to relatively small metabolic networks. Moreover, the vectors returned by existing algorithms do not, in general, represent conservation of a specific moietymore » with a defined atomic structure. Here, we show that identification of conserved moieties requires data on reaction atom mappings in addition to stoichiometry. We present a novel method to identify conserved moieties in metabolic networks by graph theoretical analysis of their underlying atom transition networks. Our method returns the exact group of atoms belonging to each conserved moiety as well as the corresponding vector in the left null space of the stoichiometric matrix. It can be implemented as a pipeline of polynomial time algorithms. Our implementation completes in under five minutes on a metabolic network with more than 4,000 mass balanced reactions. The scalability of the method enables extension of existing applications for moiety conservation relations to genome-scale metabolic networks. Finally, we also give examples of new applications made possible by elucidating the atomic structure of conserved moieties.« less
Read, Emily A; Laschinger, Heather K S
2015-07-01
To examine a theoretical model testing the effects of authentic leadership, structural empowerment and relational social capital on the mental health and job satisfaction of new graduate nurses over the first year of practice. Relational social capital is an important interpersonal organizational resource that may foster new graduate nurses' workplace well-being and promote retention. Evidence shows that authentic leadership and structural empowerment are key aspects of the work environment that support new graduate nurses; however, the mediating role of relational social capital has yet to be explored. A longitudinal survey design was used to test the hypothesized model. One hundred ninety-one new graduate nurses in Ontario with <2 years of experience completed mail surveys in January-March 2010 and 1 year later in 2011. Path analysis using structural equation modelling was used to test the theoretical model. Participants were mostly female, working full time in medicine/surgery or critical care. All measures demonstrated acceptable reliability and validity. Path analysis results supported our hypothesized model; structural empowerment mediated the relationship between authentic leadership and nurses' relational social capital, which in turn had a negative effect on mental health symptoms and a positive effect on job satisfaction. All indirect paths in the model were significant. By creating structurally empowering work environments, authentic leaders foster relational social capital among new graduate nurses leading to positive health and retention outcomes. © 2015 John Wiley & Sons Ltd.
Haraldsdóttir, Hulda S.; Fleming, Ronan M. T.
2016-01-01
Conserved moieties are groups of atoms that remain intact in all reactions of a metabolic network. Identification of conserved moieties gives insight into the structure and function of metabolic networks and facilitates metabolic modelling. All moiety conservation relations can be represented as nonnegative integer vectors in the left null space of the stoichiometric matrix corresponding to a biochemical network. Algorithms exist to compute such vectors based only on reaction stoichiometry but their computational complexity has limited their application to relatively small metabolic networks. Moreover, the vectors returned by existing algorithms do not, in general, represent conservation of a specific moiety with a defined atomic structure. Here, we show that identification of conserved moieties requires data on reaction atom mappings in addition to stoichiometry. We present a novel method to identify conserved moieties in metabolic networks by graph theoretical analysis of their underlying atom transition networks. Our method returns the exact group of atoms belonging to each conserved moiety as well as the corresponding vector in the left null space of the stoichiometric matrix. It can be implemented as a pipeline of polynomial time algorithms. Our implementation completes in under five minutes on a metabolic network with more than 4,000 mass balanced reactions. The scalability of the method enables extension of existing applications for moiety conservation relations to genome-scale metabolic networks. We also give examples of new applications made possible by elucidating the atomic structure of conserved moieties. PMID:27870845
Haraldsdóttir, Hulda S.; Fleming, Ronan M. T.
2016-11-21
Conserved moieties are groups of atoms that remain intact in all reactions of a metabolic network. Identification of conserved moieties gives insight into the structure and function of metabolic networks and facilitates metabolic modelling. All moiety conservation relations can be represented as nonnegative integer vectors in the left null space of the stoichiometric matrix corresponding to a biochemical network. Algorithms exist to compute such vectors based only on reaction stoichiometry but their computational complexity has limited their application to relatively small metabolic networks. Moreover, the vectors returned by existing algorithms do not, in general, represent conservation of a specific moietymore » with a defined atomic structure. Here, we show that identification of conserved moieties requires data on reaction atom mappings in addition to stoichiometry. We present a novel method to identify conserved moieties in metabolic networks by graph theoretical analysis of their underlying atom transition networks. Our method returns the exact group of atoms belonging to each conserved moiety as well as the corresponding vector in the left null space of the stoichiometric matrix. It can be implemented as a pipeline of polynomial time algorithms. Our implementation completes in under five minutes on a metabolic network with more than 4,000 mass balanced reactions. The scalability of the method enables extension of existing applications for moiety conservation relations to genome-scale metabolic networks. Finally, we also give examples of new applications made possible by elucidating the atomic structure of conserved moieties.« less
Haraldsdóttir, Hulda S; Fleming, Ronan M T
2016-11-01
Conserved moieties are groups of atoms that remain intact in all reactions of a metabolic network. Identification of conserved moieties gives insight into the structure and function of metabolic networks and facilitates metabolic modelling. All moiety conservation relations can be represented as nonnegative integer vectors in the left null space of the stoichiometric matrix corresponding to a biochemical network. Algorithms exist to compute such vectors based only on reaction stoichiometry but their computational complexity has limited their application to relatively small metabolic networks. Moreover, the vectors returned by existing algorithms do not, in general, represent conservation of a specific moiety with a defined atomic structure. Here, we show that identification of conserved moieties requires data on reaction atom mappings in addition to stoichiometry. We present a novel method to identify conserved moieties in metabolic networks by graph theoretical analysis of their underlying atom transition networks. Our method returns the exact group of atoms belonging to each conserved moiety as well as the corresponding vector in the left null space of the stoichiometric matrix. It can be implemented as a pipeline of polynomial time algorithms. Our implementation completes in under five minutes on a metabolic network with more than 4,000 mass balanced reactions. The scalability of the method enables extension of existing applications for moiety conservation relations to genome-scale metabolic networks. We also give examples of new applications made possible by elucidating the atomic structure of conserved moieties.
DOT National Transportation Integrated Search
1979-09-01
Volume II of Theoretical Studies of Microstrip Antennas deals with the analysis and synthesis of several types of novel multi-resonant elements with emphasis on dual-frequency operation of rectangular microstrip patch antennas with or without externa...
Mg I as a probe of the solar chromosphere - The atomic model
NASA Technical Reports Server (NTRS)
Mauas, Pablo J.; Avrett, Eugene H.; Loeser, Rudolf
1988-01-01
This paper presents a complete atomic model for Mg I line synthesis, where all the atomic parameters are based on recent experimental and theoretical data. It is shown how the computed profiles at 4571 A and 5173 A are influenced by the choice of these parameters and the number of levels included in the model atom. In addition, observed profiles of the 5173 A b2 line and theoretical profiles for comparison (based on a recent atmospheric model for the average quiet sun) are presented.
Ruiz, Eliseo; Cano, Joan; Alvarez, Santiago; Caneschi, Andrea; Gatteschi, Dante
2003-06-04
A theoretical density functional study of the exchange coupling in hexanuclear polysiloxanolato-bridged complexes of Cu(II) and Ni(II) is presented. By calculating the energies of three different spin configurations, we can obtain estimates of the first-, second-, and third-neighbor exchange coupling constants. The study has been carried out for the complete structures of the Cu pristine cluster and of the chloroenclathrated Ni complex as well as for the hypotethical pristine Ni compound and for magnetically dinuclear analogues M(2)Zn(4) (M = Cu, Ni).
Structural properties of lead-lithium alloys
NASA Astrophysics Data System (ADS)
Khambholja, S. G.; Satikunvar, D. D.; Abhishek, Agraj; Thakore, B. Y.
2018-05-01
Lead-Lihtium alloys have found large number of applications as liquid metal coolants in nuclear reactors. Large number of experimental work is reported for this system. However, complete theoretical description is still rare. In this scenario, we in the present work report the study of ground state properties of Lead-Lithium system. The present study is performed using plane wave pseudopotential density functional theory as implemented in Quantum ESPRESSO package. The theoretical findings are in agreement with previously reported experimental data. Some conclusions are drawn based on present study, which will be helpful for a comprehensive study.
The Situation of ICT Usage in Nagoya University Law School
NASA Astrophysics Data System (ADS)
Kaneko, Daisuke; Sugawara, Ikuo
Since the introduction of a new legal education system in 2004, some of Japanese legal educational institutions have changed into professional schools which names are Law School. These law schools are required not only theoretical studies but also professional skills training. Law students, however, have limited time to complete this agenda, so law professors have to teach courses effectively. In this paper, the authors present the situation of ICT usage in Nagoya University Law School as a case study to describe and to critique systems to support theoretical studies and professional skills training.
Complete Mechanism of Hemithioindigo Motor Rotation.
Wilcken, Roland; Schildhauer, Monika; Rott, Florian; Huber, Ludwig Alexander; Guentner, Manuel; Thumser, Stefan; Hoffmann, Kerstin; Oesterling, Sven; de Vivie-Riedle, Regina; Riedle, Eberhard; Dube, Henry
2018-04-18
Hemithioindigo-based molecular motors are powered by nondamaging visible light and provide very fast directional rotations at ambient conditions. Their ground state energy profile has been probed in detail, but the crucial excited state processes are completely unknown so far. In addition, very fast processes in the ground state are also still elusive to date and thus knowledge of the whole operational mechanism remains to a large extent in the dark. In this work we elucidate the complete light-driven rotation mechanism by a combination of multiscale broadband transient absorption measurements covering a time scale from fs to ms in conjunction with a high level theoretical description of the excited state. In addition to a full description of the excited state dynamics in the various time regimes, we also provide the first experimental evidence for the elusive fourth intermediate ground state of the original HTI motor. The fate of this intermediate also is followed directly proving complete unidirectionality for both 180° rotation steps. At the same time, we uncover the hitherto unknown involvement of an unproductive triplet state pathway, which slightly diminishes the quantum yield of the E to Z photoisomerization. A rate model analysis shows that increasing the speed of motor rotation is most effectively done by increasing the photoisomerization quantum yields instead of barrier reduction for the thermal ratcheting steps. Our findings are of crucial importance for improved future designs of any light-driven molecular motor in general to yield better efficiencies and applicability.
Experimental and theoretical study of magnetohydrodynamic ship models.
Cébron, David; Viroulet, Sylvain; Vidal, Jérémie; Masson, Jean-Paul; Viroulet, Philippe
2017-01-01
Magnetohydrodynamic (MHD) ships represent a clear demonstration of the Lorentz force in fluids, which explains the number of students practicals or exercises described on the web. However, the related literature is rather specific and no complete comparison between theory and typical small scale experiments is currently available. This work provides, in a self-consistent framework, a detailed presentation of the relevant theoretical equations for small MHD ships and experimental measurements for future benchmarks. Theoretical results of the literature are adapted to these simple battery/magnets powered ships moving on salt water. Comparison between theory and experiments are performed to validate each theoretical step such as the Tafel and the Kohlrausch laws, or the predicted ship speed. A successful agreement is obtained without any adjustable parameter. Finally, based on these results, an optimal design is then deduced from the theory. Therefore this work provides a solid theoretical and experimental ground for small scale MHD ships, by presenting in detail several approximations and how they affect the boat efficiency. Moreover, the theory is general enough to be adapted to other contexts, such as large scale ships or industrial flow measurement techniques.
Experimental and theoretical study of magnetohydrodynamic ship models
Viroulet, Sylvain; Vidal, Jérémie; Masson, Jean-Paul; Viroulet, Philippe
2017-01-01
Magnetohydrodynamic (MHD) ships represent a clear demonstration of the Lorentz force in fluids, which explains the number of students practicals or exercises described on the web. However, the related literature is rather specific and no complete comparison between theory and typical small scale experiments is currently available. This work provides, in a self-consistent framework, a detailed presentation of the relevant theoretical equations for small MHD ships and experimental measurements for future benchmarks. Theoretical results of the literature are adapted to these simple battery/magnets powered ships moving on salt water. Comparison between theory and experiments are performed to validate each theoretical step such as the Tafel and the Kohlrausch laws, or the predicted ship speed. A successful agreement is obtained without any adjustable parameter. Finally, based on these results, an optimal design is then deduced from the theory. Therefore this work provides a solid theoretical and experimental ground for small scale MHD ships, by presenting in detail several approximations and how they affect the boat efficiency. Moreover, the theory is general enough to be adapted to other contexts, such as large scale ships or industrial flow measurement techniques. PMID:28665941
Baker, Dian
2011-01-01
Asian and Pacific Islander Americans (A&PIAs) are experiencing health inequities. For example, A&PIA is the only racial/ethnic group in America to experience cancer as their leading cause of death. Several studies within the A&PIA population have pointed to acculturation as a significant variable to explain their health and health-seeking behaviors. Acculturation is a key construct in understanding the health of the A&PIA population. The purpose of this concept analysis is to provide a current conceptual understanding of the relationship between acculturation and health, especially within the A&PIA populations, which will serve as a pragmatic guideline for nursing practice and research. Understanding the contemporary issues surrounding the conceptual application of acculturation will aid in the development of appropriate programs to reduce health inequities. Acculturation was explored using the Morse method of concept analysis. An iterative historical and contemporary literature review across the disciplines of anthropology, sociology, psychology, medicine, and nursing was completed. Analytical questions asked of the resultant data provided the theoretical definition, antecedents, key attributes, outcomes, and implications. The concept analysis resulted in a new theoretical definition that includes multidimensional concepts of acculturation. Dilemmas in the measurement of key attributes of acculturation include unidirectional and bidirectional analysis, psychometric issues, and the appropriateness of proxy measurements. Outcomes of acculturation on health can be positive or negative and depend on an individual's or group's ability to navigate freely with necessary supports. Results of the conceptual analysis resulted in recommendations for nursing practice and future acculturation research. While debate continues about the appropriate use and definition of acculturation, researchers agree that it is an important construct in understanding the health of migrating individuals and groups. Currently there is no testable framework that delineates the role of acculturation in health. Further research is indicated to clarify the relationship between acculturation and health. © 2011 Wiley Periodicals, Inc.
Morgese, Giorgia; Lombardo, Giovanni Pietro; Albani, Alessandra
2016-11-01
This article examines the areas of research conducted at the Laboratory of Experimental Psychology of the University of Rome from 1907 to 1947, directed first by Sante De Sanctis (1862-1935), and then, from 1931 on, by Mario Ponzo (1882-1960). The method used to distinguish the topics and areas of research that characterized the Roman School during this period is the textual analysis of the titles of the journal in which studies completed at the laboratory were published, namely, Contributi del Laboratorio di Psicologia sperimentale [Psychological Contributions of the Laboratory of Experimental Psychology]. This empirical analysis, which complements and supports the historiographical interpretation, demonstrates the disciplines that emerged under a system managed by the directors over 2 periods of time in the pursuit of scientific psychology in Rome and in Italy. This analysis highlights the process of adjustment from a traditional, general approach to a more theoretical-technical application. This article is a new contribution to the Italian debate on the periodization of the "crisis" in Italian psychology. (PsycINFO Database Record (c) 2016 APA, all rights reserved).
Non-Markovian closure kinetics of flexible polymers with hydrodynamic interactions.
Levernier, N; Dolgushev, M; Bénichou, O; Blumen, A; Guérin, T; Voituriez, R
2015-11-28
This paper presents a theoretical analysis of the closure kinetics of a polymer with hydrodynamic interactions. This analysis, which takes into account the non-Markovian dynamics of the end-to-end vector and relies on the preaveraging of the mobility tensor (Zimm dynamics), is shown to reproduce very accurately the results of numerical simulations of the complete nonlinear dynamics. It is found that Markovian treatments based on a Wilemski-Fixman approximation significantly overestimate cyclization times (up to a factor 2), showing the importance of memory effects in the dynamics. In addition, this analysis provides scaling laws of the mean first cyclization time (MFCT) with the polymer size N and capture radius b, which are identical in both Markovian and non-Markovian approaches. In particular, it is found that the scaling of the MFCT for large N is given by T ∼ N(3/2)ln(N/b(2)), which differs from the case of the Rouse dynamics where T ∼ N(2). The extension to the case of the reaction kinetics of a monomer of a Zimm polymer with an external target in a confined volume is also presented.
Leadership: validation of a self-report scale.
Dussault, Marc; Frenette, Eric; Fernet, Claude
2013-04-01
The aim of this paper was to propose and test the factor structure of a new self-report questionnaire on leadership. A sample of 373 school principals in the Province of Quebec, Canada completed the initial 46-item version of the questionnaire. In order to obtain a questionnaire of minimal length, a four-step procedure was retained. First, items analysis was performed using Classical Test Theory. Second, Rasch analysis was used to identify non-fitting or overlapping items. Third, a confirmatory factor analysis (CFA) using structural equation modelling was performed on the 21 remaining items to verify the factor structure of the scale. Results show that the model with a single third-order dimension (leadership), two second-order dimensions (transactional and transformational leadership), and one first-order dimension (laissez-faire leadership) provides a good fit to the data. Finally, invariance of factor structure was assessed with a second sample of 222 vice-principals in the Province of Quebec, Canada. This model is in agreement with the theoretical model developed by Bass (1985), upon which the questionnaire is based.
Simulation of the MELiSSA closed loop system as a tool to define its integration strategy
NASA Astrophysics Data System (ADS)
Poughon, Laurent; Farges, Berangere; Dussap, Claude-Gilles; Godia, Francesc; Lasseur, Christophe
Inspired from a terrestrial ecosystem, MELiSSA (Micro Ecological Life Support System Alternative) is a project of closed life support system future long-term manned missions (Moon and Mars bases). Started on ESA in 1989, this 5 compartments concept has evolved following a mechanistic engineering approach for acquiring both theoretical and technical knowledge. In its current state of development the project can now start to demonstrate the MELiSSA loop concept at a pilot scale. Thus an integration strategy for a MELiSSA Pilot Plant (MPP) was defined, describing the different phases for tests and connections between compartments. The integration steps should be started in 2008 and be completed with a complete operational loop in 2015, which final objective is to achieve a closed liquid and gas loop with 100 Although the integration logic could start with the most advanced processes in terms of knowledge and hardware development, this logic needs to be completed by high politic of simulation. Thanks to this simulation exercise, the effective demonstrations of each independent process and its progressive coupling with others will be performed in operational conditions as close as possible to the final configuration. The theoretical approach described in this paper is based on mass balance models of each of the MELiSSA biological compartments which are used to simulate each integration step and the complete MPP loop itself. These simulations will help to identify criticalities of each integration steps and to check the consistencies between objectives, flows, recycling efficiencies and sizing of the pilot reactors. A MPP scenario compatible with the current knowledge of the operation of the pilot reactors was investigated and the theoretical performances of the system compared to the objectives of the MPP. From this scenario the most important milestone steps in the integration are highlighted and their behaviour can be simulated.
New Physics Undercover at the LHC
NASA Astrophysics Data System (ADS)
Lou, Hou Keong
With the completion of 7 TeV and 8 TeV data taking at the Large Hadron Collider (LHC), the physics community witnessed one of the great triumphs of modern physics: the completion of the Standard Model (SM) as an effective theory. The final missing particle, the Higgs boson, was observed and its mass was measured. However, many theoretical questions remain unanswered. What is the source of electroweak symmetry breaking? What is the nature of dark matter? How does gravity fit into the picture? With no definitive hints of new physics at the LHC, we must consider the possibility that our search strategies need to be expanded. Conventional LHC searches focus on theoretically motivated scenarios, such as the Minimal Supersymmetric Standard Models and Little Higgs Theories. However, it is possible that new physics may be entirely different from what we might expect. In this thesis, we examine a variety of scenarios that lead to new physics undercover at the LHC. First we look at potential new physics hiding in Quantum Chromo-Dynamics backgrounds, which may be uncovered using jet substructure techniques in a data-driven way. Then we turn to new long-lived particles hiding in Higgs decay, which may lead to displaced vertices. Such a signal can be unearthed through a data-driven analysis. Then we turn to new physics with ``semi-visible jets'', which lead to missing momentum aligned with jet momentum. These events are vetoed in traditional searches and we demonstrate ways to uncover these signals. Lastly, we explore performance of future colliders in two case studies: Stops and Higgs Portal searches. We show that a 100 TeV collider will lead to significant improvements over 14 TeV LHC runs. Indeed, new physics may lie undercover at the LHC and future colliders, waiting to be discovered.
Haney, Matthew M.; Mikesell, T. Dylan; van Wijk, Kasper; Nakahara, Hisashi
2012-01-01
Using ambient seismic noise for imaging subsurface structure dates back to the development of the spatial autocorrelation (SPAC) method in the 1950s. We present a theoretical analysis of the SPAC method for multicomponent recordings of surface waves to determine the complete 3 × 3 matrix of correlations between all pairs of three-component motions, called the correlation matrix. In the case of isotropic incidence, when either Rayleigh or Love waves arrive from all directions with equal power, the only non-zero off-diagonal terms in the matrix are the vertical–radial (ZR) and radial–vertical (RZ) correlations in the presence of Rayleigh waves. Such combinations were not considered in the development of the SPAC method. The method originally addressed the vertical–vertical (ZZ), RR and TT correlations, hence the name spatial autocorrelation. The theoretical expressions we derive for the ZR and RZ correlations offer additional ways to measure Rayleigh wave dispersion within the SPAC framework. Expanding on the results for isotropic incidence, we derive the complete correlation matrix in the case of generally anisotropic incidence. We show that the ZR and RZ correlations have advantageous properties in the presence of an out-of-plane directional wavefield compared to ZZ and RR correlations. We apply the results for mixed-component correlations to a data set from Akutan Volcano, Alaska and find consistent estimates of Rayleigh wave phase velocity from ZR compared to ZZ correlations. This work together with the recently discovered connections between the SPAC method and time-domain correlations of ambient noise provide further insights into the retrieval of surface wave Green’s functions from seismic noise.
Simultaneous spreading and evaporation: recent developments.
Semenov, Sergey; Trybala, Anna; Rubio, Ramon G; Kovalchuk, Nina; Starov, Victor; Velarde, Manuel G
2014-04-01
The recent progress in theoretical and experimental studies of simultaneous spreading and evaporation of liquid droplets on solid substrates is discussed for pure liquids including nanodroplets, nanosuspensions of inorganic particles (nanofluids) and surfactant solutions. Evaporation of both complete wetting and partial wetting liquids into a nonsaturated vapour atmosphere are considered. However, the main attention is paid to the case of partial wetting when the hysteresis of static contact angle takes place. In the case of complete wetting the spreading/evaporation process proceeds in two stages. A theory was suggested for this case and a good agreement with available experimental data was achieved. In the case of partial wetting the spreading/evaporation of a sessile droplet of pure liquid goes through four subsequent stages: (i) the initial stage, spreading, is relatively short (1-2 min) and therefore evaporation can be neglected during this stage; during the initial stage the contact angle reaches the value of advancing contact angle and the radius of the droplet base reaches its maximum value, (ii) the first stage of evaporation is characterised by the constant value of the radius of the droplet base; the value of the contact angle during the first stage decreases from static advancing to static receding contact angle; (iii) during the second stage of evaporation the contact angle remains constant and equal to its receding value, while the radius of the droplet base decreases; and (iv) at the third stage of evaporation both the contact angle and the radius of the droplet base decrease until the drop completely disappears. It has been shown theoretically and confirmed experimentally that during the first and second stages of evaporation the volume of droplet to power 2/3 decreases linearly with time. The universal dependence of the contact angle during the first stage and of the radius of the droplet base during the second stage on the reduced time has been derived theoretically and confirmed experimentally. The theory developed for pure liquids is applicable also to nanofluids, where a good agreement with the available experimental data has been found. However, in the case of evaporation of surfactant solutions the process deviates from the theoretical predictions for pure liquids at concentration below critical wetting concentration and is in agreement with the theoretical predictions at concentrations above it. Crown Copyright © 2013. All rights reserved.
McParlin, Catherine; Bell, Ruth; Robson, Stephen C; Muirhead, Colin R; Araújo-Soares, Vera
2017-06-01
to investigate barriers and facilitators to physical activity (PA) guideline implementation for midwives when advising obese pregnant women. a cross-sectional, self-completion, anonymous questionnaire was designed using the Theoretical Domains Framework. this framework was developed to evaluate the implementation of guidelines by health care professionals. A total of 40 questions were included. These were informed by previous research on pregnant women's and midwives views, knowledge and attitudes to PA, and supported by national evidence based guidelines. Demographic information and free text comments were also collected. three diverse NHS Trusts in the North East of England. all midwives employed by two hospital Trusts and the community midwives from the third Trust (n=375) were invited to participate. mean domain scores were calculated. Factor and regression analysis were performed to describe which theoretical domains may be influencing practice. Free text comments were analysed thematically. 192 (53%) questionnaires were returned. Mean domain scores were highest for social professional role and knowledge, and lowest for skills, beliefs about capabilities and behaviour regulation. Regression analysis indicated that skills and memory/attention/decision domains had a statistically significant influence on midwives discussing PA with obese pregnant women and advising them accordingly. Midwives comments indicated that they felt it was part of their role to discuss PA with all pregnant women but felt they lacked the skills and resources to do so effectively. midwives seem to have the necessary knowledge about the need/importance of PA advice for obese women and believe it is part of their role, but perceive they lack necessary skills and resources, and do not plan or prioritise the discussion regarding PA with obese pregnant woman. designing interventions that improve skills, promote routine enquiry regarding PA and provide resources (eg. information, referral pathways) may help improve midwives' PA advice. Copyright © 2016 Elsevier Ltd. All rights reserved.
Computational Methods for Control in Partial Differential Equations
1998-07-13
supported in part under this grant are C. Musante (Ph.D. thesis completed in May, 1998), M. Buksas (Ph.D. thesis to be completed in August, 1998) and M...continuing initial promising simulation findings. A summary of theoretical and numerical results to date is given in the Ph.D. thesis of Musante [4]. II... Musante and Buksas in visits to Brooks Air Force Base. The collaborations intensified during 1997 with the following visits: 1. June 15-August 30
Fluid-structure finite-element vibrational analysis
NASA Technical Reports Server (NTRS)
Feng, G. C.; Kiefling, L.
1974-01-01
A fluid finite element has been developed for a quasi-compressible fluid. Both kinetic and potential energy are expressed as functions of nodal displacements. Thus, the formulation is similar to that used for structural elements, with the only differences being that the fluid can possess gravitational potential, and the constitutive equations for fluid contain no shear coefficients. Using this approach, structural and fluid elements can be used interchangeably in existing efficient sparse-matrix structural computer programs such as SPAR. The theoretical development of the element formulations and the relationships of the local and global coordinates are shown. Solutions of fluid slosh, liquid compressibility, and coupled fluid-shell oscillation problems which were completed using a temporary digital computer program are shown. The frequency correlation of the solutions with classical theory is excellent.
Thermo-solutal growth of an anisotropic dendrite with six-fold symmetry
NASA Astrophysics Data System (ADS)
Alexandrov, D. V.; Galenko, P. K.
2018-03-01
A stable growth of dendritic crystal with the six-fold crystalline anisotropy is analyzed in a binary nonisothermal mixture. A selection criterion representing a relationship between the dendrite tip velocity and its tip diameter is derived on the basis of morphological stability analysis and solvability theory. A complete set of nonlinear equations, consisting of the selection criterion and undercooling balance condition, which determines implicit dependencies of the dendrite tip velocity and tip diameter as functions of the total undercooling, is formulated. Exact analytical solutions of these nonlinear equations are found in a parametric form. Asymptotic solutions describing the crystal growth at small Péclet numbers are determined. Theoretical predictions are compared with experimental data obtained for ice dendrites growing in binary water-ethylenglycol solutions as well as in pure water.
A theoretical study of heterojunction and graded band gap type solar cells
NASA Technical Reports Server (NTRS)
Sutherland, J. E.; Hauser, J. R.
1977-01-01
A computer program was designed for the analysis of variable composition solar cells and applied to several proposed solar cell structures using appropriate semiconductor materials. The program simulates solar cells made of a ternary alloy of two binary semiconductors with an arbitrary composition profile, and an abrupt or Gaussian doping profile of polarity n-on-p or p-on-n with arbitrary doping levels. Once the device structure is specified, the program numerically solves a complete set of differential equations and calculates electrostatic potential, quasi-Fermi levels, carrier concentrations and current densities, total current density and efficiency as functions of terminal voltage and position within the cell. These results are then recorded by computer in tabulated or plotted form for interpretation by the user.
NASA Astrophysics Data System (ADS)
Saleem, H.; Subashchandrabose, S.; Ramesh Babu, N.; Syed Ali Padusha, M.
2015-05-01
The FT-IR, FT-Raman and UV-Vis spectra of the Schiff base compound (E)-N‧-(4-methoxybenzylidene) benzohydrazide (MBBH) have been recorded and analyzed. The optimized geometrical parameters were calculated. The complete vibrational assignments were performed on the basis of TED of the vibrational modes, calculated with the help of SQM method. NBO analysis has been carried out to explore the hyperconjugative interactions and their second order stabilization energy within the molecule. The molecular orbitals (MO's) and its energy gap were studied. The first order hyperpolarizability (β0) and related properties (β, α0, Δα) of MBBH are also calculated. All theoretical calculations were performed on the basis of B3LYP/6-311++G(d,p) level of theory.
FTIR, FT-Raman spectra and ab initio, DFT vibrational analysis of 2,4-dinitrophenylhydrazine.
Sundaraganesan, N; Ayyappan, S; Umamaheswari, H; Joshua, B Dominic
2007-01-01
The FTIR and FT-Raman spectra of 2,4-dinitrophenylhydrazine (2,4-DNPH) has been recorded in the region 4000-400 and 3500-50cm-1, respectively. The optimized geometry, frequency and intensity of the vibrational bands of 2,4-DNPH were obtained by the ab initio and density functional theory (DFT) levels of theory with complete relaxation in the potential energy surface using 6-31G(d,p) and 6-311G(d,p) basis sets. The harmonic vibrational frequencies were calculated and the scaled values have been compared with experimental FTIR and FT-Raman spectra. The observed and the calculated frequencies are found to be in good agreement. The experimental spectra also coincide satisfactorily with those of theoretically constructed bar type spectrograms.
FTIR, FT-Raman spectra and ab initio, DFT vibrational analysis of 2,4-dinitrophenylhydrazine
NASA Astrophysics Data System (ADS)
Sundaraganesan, N.; Ayyappan, S.; Umamaheswari, H.; Dominic Joshua, B.
2007-01-01
The FTIR and FT-Raman spectra of 2,4-dinitrophenylhydrazine (2,4-DNPH) has been recorded in the region 4000-400 and 3500-50 cm -1, respectively. The optimized geometry, frequency and intensity of the vibrational bands of 2,4-DNPH were obtained by the ab initio and density functional theory (DFT) levels of theory with complete relaxation in the potential energy surface using 6-31G(d,p) and 6-311G(d,p) basis sets. The harmonic vibrational frequencies were calculated and the scaled values have been compared with experimental FTIR and FT-Raman spectra. The observed and the calculated frequencies are found to be in good agreement. The experimental spectra also coincide satisfactorily with those of theoretically constructed bar type spectrograms.
Electrons on a spherical surface: Physical properties and hollow spherical clusters
NASA Astrophysics Data System (ADS)
Cricchio, Dario; Fiordilino, Emilio; Persico, Franco
2012-07-01
We discuss the physical properties of a noninteracting electron gas constrained to a spherical surface. In particular we consider its chemical potentials, its ionization potential, and its electric static polarizability. All these properties are discussed analytically as functions of the number N of electrons. The trends obtained with increasing N are compared with those of the corresponding properties experimentally measured or theoretically evaluated for quasispherical hollow atomic and molecular clusters. Most of the properties investigated display similar trends, characterized by a prominence of shell effects. This leads to the definition of a scale-invariant distribution of magic numbers which follows a power law with critical exponent -0.5. We conclude that our completely mechanistic and analytically tractable model can be useful for the analysis of self-assembling complex systems.
Identification of dynamic systems, theory and formulation
NASA Technical Reports Server (NTRS)
Maine, R. E.; Iliff, K. W.
1985-01-01
The problem of estimating parameters of dynamic systems is addressed in order to present the theoretical basis of system identification and parameter estimation in a manner that is complete and rigorous, yet understandable with minimal prerequisites. Maximum likelihood and related estimators are highlighted. The approach used requires familiarity with calculus, linear algebra, and probability, but does not require knowledge of stochastic processes or functional analysis. The treatment emphasizes unification of the various areas in estimation in dynamic systems is treated as a direct outgrowth of the static system theory. Topics covered include basic concepts and definitions; numerical optimization methods; probability; statistical estimators; estimation in static systems; stochastic processes; state estimation in dynamic systems; output error, filter error, and equation error methods of parameter estimation in dynamic systems, and the accuracy of the estimates.
NASA Astrophysics Data System (ADS)
Bai, Danyu
2015-08-01
This paper discusses the flow shop scheduling problem to minimise the total quadratic completion time (TQCT) with release dates in offline and online environments. For this NP-hard problem, the investigation is focused on the performance of two online algorithms based on the Shortest Processing Time among Available jobs rule. Theoretical results indicate the asymptotic optimality of the algorithms as the problem scale is sufficiently large. To further enhance the quality of the original solutions, the improvement scheme is provided for these algorithms. A new lower bound with performance guarantee is provided, and computational experiments show the effectiveness of these heuristics. Moreover, several results of the single-machine TQCT problem with release dates are also obtained for the deduction of the main theorem.
Zero-order bows in radially inhomogeneous spheres: direct and inverse problems.
Adam, John A
2011-10-01
Zero-order ray paths are examined in radially inhomogeneous spheres with differentiable refractive index profiles. It is demonstrated that zero-order and sometimes twin zero-order bows can exist when the gradient of refractive index is sufficiently negative. Abel inversion is used to "recover" the refractive index profiles; it is therefore possible in principle to specify the nature and type of bows and determine the refractive index profile that induces them. This may be of interest in the field of rainbow refractometry and optical fiber studies. This ray-theoretic analysis has direct similarities with the phenomenon of "orbiting" and other phenomena in scattering theory and also in seismological, surface gravity wave, and gravitational "lensing" studies. For completeness these topics are briefly discussed in the appendixes; they may also be of pedagogic interest.
Absorption of the laser radiation by the laser plasma with gas microjet targets
NASA Astrophysics Data System (ADS)
Borisevichus, D. A.; Zabrodskii, V. V.; Kalmykov, S. G.; Sasin, M. E.; Seisyan, R. P.
2017-01-01
An upper limit of absorption of the laser radiation in the plasma produced in a gas jet Xe target with the average density of (3-6) × 1018 cm-3 and the effective diameter of 0.7 mm is found. It is equal to ≈50% and remains constant under any variation in this range of densities. This result contradicts both theoretical assessments that have predicted virtually complete absorption and results of earlier experiments with the laser spark in an unlimited stationary Xe gas with the same density, where the upper limit of absorption was close to 100%. An analysis shows that nonlinearity of absorption and plasma nonequilibrium lead to the reduction of the absorption coefficient that, along with the limited size of plasma, can explain the experimental results.
Lindberg, Elisabeth; Österberg, Sofia A; Hörberg, Ulrica
2016-01-01
Phenomena in caring science are often complex and laden with meanings. Empirical research with the aim of capturing lived experiences is one way of revealing the complexity. Sometimes, however, results from empirical research need to be further discussed. One way is to further abstract the result and/or philosophically examine it. This has previously been performed and presented in scientific journals and doctoral theses, contributing to a greater understanding of phenomena in caring science. Although the intentions in many of these publications are laudable, the lack of methodological descriptions as well as a theoretical and systematic foundation can contribute to an ambiguity concerning how the results have emerged during the analysis. The aim of this paper is to describe the methodological support for the further abstraction of and/or philosophical examination of empirical findings. When trying to systematize the support procedures, we have used a reflective lifeworld research (RLR) approach. Based on the assumptions in RLR, this article will present methodological support for a theoretical examination that can include two stages. In the first stage, data from several (two or more) empirical results on an essential level are synthesized into a general structure. Sometimes the analysis ends with the general structure, but sometimes there is a need to proceed further. The second stage can then be a philosophical examination, in which the general structure is discussed in relation to a philosophical text, theory, or concept. It is important that the theories are brought in as the final stage after the completion of the analysis. Core dimensions of the described methodological support are, in accordance with RLR, openness, bridling, and reflection. The methodological support cannot be understood as fixed stages, but rather as a guiding light in the search for further meanings.
Matsuda, Fumio; Shinbo, Yoko; Oikawa, Akira; Hirai, Masami Yokota; Fiehn, Oliver; Kanaya, Shigehiko; Saito, Kazuki
2009-01-01
Background In metabolomics researches using mass spectrometry (MS), systematic searching of high-resolution mass data against compound databases is often the first step of metabolite annotation to determine elemental compositions possessing similar theoretical mass numbers. However, incorrect hits derived from errors in mass analyses will be included in the results of elemental composition searches. To assess the quality of peak annotation information, a novel methodology for false discovery rates (FDR) evaluation is presented in this study. Based on the FDR analyses, several aspects of an elemental composition search, including setting a threshold, estimating FDR, and the types of elemental composition databases most reliable for searching are discussed. Methodology/Principal Findings The FDR can be determined from one measured value (i.e., the hit rate for search queries) and four parameters determined by Monte Carlo simulation. The results indicate that relatively high FDR values (30–50%) were obtained when searching time-of-flight (TOF)/MS data using the KNApSAcK and KEGG databases. In addition, searches against large all-in-one databases (e.g., PubChem) always produced unacceptable results (FDR >70%). The estimated FDRs suggest that the quality of search results can be improved not only by performing more accurate mass analysis but also by modifying the properties of the compound database. A theoretical analysis indicates that FDR could be improved by using compound database with smaller but higher completeness entries. Conclusions/Significance High accuracy mass analysis, such as Fourier transform (FT)-MS, is needed for reliable annotation (FDR <10%). In addition, a small, customized compound database is preferable for high-quality annotation of metabolome data. PMID:19847304
Petri net modelling of gene regulation of the Duchenne muscular dystrophy.
Grunwald, Stefanie; Speer, Astrid; Ackermann, Jörg; Koch, Ina
2008-05-01
Searching for therapeutic strategies for Duchenne muscular dystrophy, it is of great interest to understand the responsible molecular pathways down-stream of dystrophin completely. For this reason we have performed real-time PCR experiments to compare mRNA expression levels of relevant genes in tissues of affected patients and controls. To bring experimental data in context with the underlying pathway theoretical models are needed. Modelling of biological processes in the cell at higher description levels is still an open problem in the field of systems biology. In this paper, a new application of Petri net theory is presented to model gene regulatory processes of Duchenne muscular dystrophy. We have developed a Petri net model, which is based mainly on own experimental and literature data. We distinguish between up- and down-regulated states of gene expression. The analysis of the model comprises the computation of structural and dynamic properties with focus on a thorough T-invariant analysis, including clustering techniques and the decomposition of the network into maximal common transition sets (MCT-sets), which can be interpreted as functionally related building blocks. All possible pathways, which reflect the complex net behaviour in dependence of different gene expression patterns, are discussed. We introduce Mauritius maps of T-invariants, which enable, for example, theoretical knockout analysis. The resulted model serves as basis for a better understanding of pathological processes, and thereby for planning next experimental steps in searching for new therapeutic possibilities. Free availability of the Petri net editor and animator Snoopy and the clustering tool PInA via http://www-dssz.informatik.tu-cottbus.de/~ wwwdssz/. The Petri net models used can be accessed via http://www.tfh-berlin.de/bi/duchenne/.
Collectivistic Self-Construal and Forgiveness
ERIC Educational Resources Information Center
Hook, Joshua N.; Worthington, Everett L., Jr.; Utsey, Shawn O.; Davis, Don E.; Burnette, Jeni L.
2012-01-01
This study tested a theoretical model of the relationship between collectivism and forgiveness. Participants (N= 298) completed measures of collectivistic self-construal, forgiveness, and forgiveness-related constructs. A collectivistic self-was related to understanding forgiveness as an interpersonal process that involved reconciliation.…
Development of a prototype spatial information processing system for hydrologic research
NASA Technical Reports Server (NTRS)
Sircar, Jayanta K.
1991-01-01
Significant advances have been made in the last decade in the areas of Geographic Information Systems (GIS) and spatial analysis technology, both in hardware and software. Science user requirements are so problem specific that currently no single system can satisfy all of the needs. The work presented here forms part of a conceptual framework for an all-encompassing science-user workstation system. While definition and development of the system as a whole will take several years, it is intended that small scale projects such as the current work will address some of the more short term needs. Such projects can provide a quick mechanism to integrate tools into the workstation environment forming a larger, more complete hydrologic analysis platform. Described here are two components that are very important to the practical use of remote sensing and digital map data in hydrology. Described here is a graph-theoretic technique to rasterize elevation contour maps. Also described is a system to manipulate synthetic aperture radar (SAR) data files and extract soil moisture data.
Shell stability analysis in a computer aided engineering (CAE) environment
NASA Technical Reports Server (NTRS)
Arbocz, J.; Hol, J. M. A. M.
1993-01-01
The development of 'DISDECO', the Delft Interactive Shell DEsign COde is described. The purpose of this project is to make the accumulated theoretical, numerical and practical knowledge of the last 25 years or so readily accessible to users interested in the analysis of buckling sensitive structures. With this open ended, hierarchical, interactive computer code the user can access from his workstation successively programs of increasing complexity. The computational modules currently operational in DISDECO provide the prospective user with facilities to calculate the critical buckling loads of stiffened anisotropic shells under combined loading, to investigate the effects the various types of boundary conditions will have on the critical load, and to get a complete picture of the degrading effects the different shapes of possible initial imperfections might cause, all in one interactive session. Once a design is finalized, its collapse load can be verified by running a large refined model remotely from behind the workstation with one of the current generation 2-dimensional codes, with advanced capabilities to handle both geometric and material nonlinearities.
Balas, Vasilios I.; Hadjikakou, Sotiris K.; Hadjiliadis, Nick; Kourkoumelis, Nikolaos; Light, Mark E.; Hursthouse, Mike; Metsios, Apostolos K.; Karkabounas, Spyros
2008-01-01
A novel tri-n-butyl(IV) derivative of 2-thiobarbituric acid (HTBA) of formula [(n-Bu)3Sn(TBA) H2O] (1) has been synthesized and characterized by elemental analysis and 119Sn-NMR and FT-IR spectroscopic techniques. The crystal structure of complex 1 has been determined by single crystal X-ray diffraction analysis at 120(2) K. The geometry around Sn(IV) is trigonal bipyramidal. Three n-butyl groups and one oxygen atom from a deprotonated 2-thiobarbituric ligand are bonded to the metal center. The geometry is completed with one oxygen from a water molecule. Compound 1 exhibits potent, in vitro, cytotoxicity against sarcoma cancer cells (mesenchymal tissue) from the Wistar rat, polycyclic aromatic hydrocarbons (PAH, benzo[a]pyrene) carcinogenesis. In addition, the inhibition caused by 1, in the rate of lipoxygenase (LOX) catalyzed oxidation reaction of linoleic acid to hyperoxolinoleic acid, has been also kinetically and theoretically studied. The results are compared to that of cisplatin. PMID:18401456
A Systematic Analysis of a Deep Mouse Epididymal Sperm Proteome
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chauvin, Theodore; Xie, Fang; Liu, Tao
Spermatozoa are highly specialized cells that, when mature, are capable of navigating the female reproductive tract and fertilizing an oocyte. The sperm cell is thought to be largely quiescent in terms of transcriptional and translational activity. As a result, once it has left the male reproductive tract, the sperm cell is essentially operating with a static population of proteins. It is therefore theoretically possible to understand the protein networks contained in a sperm cell and to deduce its cellular function capabilities. To this end we have performed a proteomic analysis of mouse sperm isolated from the cauda epididymis and havemore » confidently identified 2,850 proteins, which is the most comprehensive sperm proteome for any species reported to date. These proteins comprise many complete cellular pathways, including those for energy production via glycolysis, β-oxidation and oxidative phosphorylation, protein folding and transport, and cell signaling systems. This proteome should prove a useful tool for assembly and testing of protein networks important for sperm function.« less
Ataque de nervios: relationship to anxiety sensitivity and dissociation predisposition.
Hinton, Devon E; Chong, Roberto; Pollack, Mark H; Barlow, David H; McNally, Richard J
2008-01-01
We investigated the relative importance of "fear of arousal symptoms" (i.e., anxiety sensitivity) and "dissociation tendency" in generating ataque de nervios. Puerto Rican patients attending an outpatient psychiatric clinic were assessed for ataque de nervios frequency in the previous month, and they completed the Anxiety Sensitivity Index (ASI) and the Dissociation Experiences Scale (DES). ASI scores were especially high in the ataque-positive group (M=41.6, SD=12.8) as compared with the ataque-negative group (M=27.2, SD=11.7), t(2, 68)=4.6, P<.001. Among the whole sample (N=70), in a logistic regression analysis, the ASI significantly predicted (odds ratio=2.6) the presence of ataque de nervios, but the DES did not. In a linear regression analysis, ataque severity was significantly predicted by both the ASI (beta=.46) and the DES (beta=.29). The theoretical and clinical implications of the strong relationship of the ASI to ataque severity are discussed.
Gomez, Rapson; Watson, Shaun D
2017-01-01
For the Social Phobia Scale (SPS) and the Social Interaction Anxiety Scale (SIAS) together, this study examined support for a bifactor model, and also the internal consistency reliability and external validity of the factors in this model. Participants ( N = 526) were adults from the general community who completed the SPS and SIAS. Confirmatory factor analysis (CFA) of their ratings indicated good support for the bifactor model. For this model, the loadings for all but six items were higher on the general factor than the specific factors. The three positively worded items had negligible loadings on the general factor. The general factor explained most of the common variance in the SPS and SIAS, and demonstrated good model-based internal consistency reliability (omega hierarchical) and a strong association with fear of negative evaluation and extraversion. The practical implications of the findings for the utilization of the SPS and SIAS, and the theoretical and clinical implications for social anxiety are discussed.
Gomez, Rapson; Watson, Shaun D.
2017-01-01
For the Social Phobia Scale (SPS) and the Social Interaction Anxiety Scale (SIAS) together, this study examined support for a bifactor model, and also the internal consistency reliability and external validity of the factors in this model. Participants (N = 526) were adults from the general community who completed the SPS and SIAS. Confirmatory factor analysis (CFA) of their ratings indicated good support for the bifactor model. For this model, the loadings for all but six items were higher on the general factor than the specific factors. The three positively worded items had negligible loadings on the general factor. The general factor explained most of the common variance in the SPS and SIAS, and demonstrated good model-based internal consistency reliability (omega hierarchical) and a strong association with fear of negative evaluation and extraversion. The practical implications of the findings for the utilization of the SPS and SIAS, and the theoretical and clinical implications for social anxiety are discussed. PMID:28210232
Ullrich-French, Sarah; Cox, Anne
2009-06-01
According to self-determination theory, motivation is multidimensional, with motivation regulations lying along a continuum of self-determination (Ryan & Deci, 2007). Accounting for the different types of motivation in physical activity research presents a challenge. This study used cluster analysis to identify motivation regulation profiles and examined their utility by testing profile differences in relative levels of self-determination (i.e., self-determination index), and theoretical antecedents (i.e., competence, autonomy, relatedness) and consequences (i.e., enjoyment, worry, effort, value, physical activity) of physical education motivation. Students (N= 386) in 6th- through 8th-grade physical education classes completed questionnaires of the variables listed above. Five profiles emerged, including average (n = 81), motivated (n = 82), self-determined (n = 91), low motivation (n = 73), and external (n = 59). Group difference analyses showed that students with greater levels of self-determined forms of motivation, regardless of non-self-determined motivation levels, reported the most adaptive physical education experiences.
Analysis of the Genome and Chromium Metabolism-Related Genes of Serratia sp. S2.
Dong, Lanlan; Zhou, Simin; He, Yuan; Jia, Yan; Bai, Qunhua; Deng, Peng; Gao, Jieying; Li, Yingli; Xiao, Hong
2018-05-01
This study is to investigate the genome sequence of Serratia sp. S2. The genomic DNA of Serratia sp. S2 was extracted and the sequencing library was constructed. The sequencing was carried out by Illumina 2000 and complete genomic sequences were obtained. Gene function annotation and bioinformatics analysis were performed by comparing with the known databases. The genome size of Serratia sp. S2 was 5,604,115 bp and the G+C content was 57.61%. There were 5373 protein coding genes, and 3732, 3614, and 3942 genes were respectively annotated into the GO, KEGG, and COG databases. There were 12 genes related to chromium metabolism in the Serratia sp. S2 genome. The whole genome sequence of Serratia sp. S2 is submitted to the GenBank database with gene accession number of LNRP00000000. Our findings may provide theoretical basis for the subsequent development of new biotechnology to repair environmental chromium pollution.
Analysis of opposed jet hydrogen-air counter flow diffusion flame
NASA Technical Reports Server (NTRS)
Ho, Y. H.; Isaac, K. M.
1989-01-01
A computational simulation of the opposed-jet diffusion flame is performed to study its structure and extinction limits. The present analysis concentrates on the nitrogen-diluted hydrogen-air diffusion flame, which provides the basic information for many vehicle designs such as the aerospace plane for which hydrogen is a candidate as the fuel. The computer program uses the time-marching technique to solve the energy and species equations coupled with the momentum equation solved by the collocation method. The procedure is implemented in two stages. In the first stage, a one-step forward overal chemical reaction is chosen with the gas phase chemical reaction rate determined by comparison with experimental data. In the second stage, a complete chemical reaction mechanism is introduced with detailed thermodynamic and transport property calculations. Comparison between experimental extinction data and theoretical predictions is discussed. The effects of thermal diffusion as well as Lewis number and Prandtl number variations on the diffusion flame are also presented.
A sophisticated cad tool for the creation of complex models for electromagnetic interaction analysis
NASA Astrophysics Data System (ADS)
Dion, Marc; Kashyap, Satish; Louie, Aloisius
1991-06-01
This report describes the essential features of the MS-DOS version of DIDEC-DREO, an interactive program for creating wire grid, surface patch, and cell models of complex structures for electromagnetic interaction analysis. It uses the device-independent graphics library DIGRAF and the graphics kernel system HALO, and can be executed on systems with various graphics devices. Complicated structures can be created by direct alphanumeric keyboard entry, digitization of blueprints, conversion form existing geometric structure files, and merging of simple geometric shapes. A completed DIDEC geometric file may then be converted to the format required for input to a variety of time domain and frequency domain electromagnetic interaction codes. This report gives a detailed description of the program DIDEC-DREO, its installation, and its theoretical background. Each available interactive command is described. The associated program HEDRON which generates simple geometric shapes, and other programs that extract the current amplitude data from electromagnetic interaction code outputs, are also discussed.
NASA Technical Reports Server (NTRS)
Ramachandran, N.; Leslie, F. W.
2004-01-01
The effect of convection during the crystallization of proteins is not very well understood. In a gravitational field, convection is caused by crystal sedimentation and by solutal buoyancy induced flow and these can lead to crystal imperfections. While crystallization in microgravity can approach diffusion limited growth conditions (no convection), terrestrially strong magnetic fields can be used to control fluid flow and sedimentation effects. In this work, we develop the analysis for magnetic flow control and test the predictions using analog experiments. Specifically, experiments on solutal convection in a paramagnetic fluid were conducted in a strong magnetic field gradient using a dilute solution of Manganese Chloride. The observed flows indicate that the magnetic field can completely counter the settling effects of gravity locally and are consistent with the theoretical predictions presented. This phenomenon suggests that magnetic fields may be useful in mimicking the microgravity environment of space for some crystal growth ana biological applications where fluid convection is undesirable.
Sawada, Tadayuki
2013-12-01
This study examined the relationship among human relations in the workplace, job involvement, affective commitment and continuance commitment with occupational and organizational commitment, and well-being. Questionnaires were completed by 855 female nurses who worked in four public hospitals (mean age = 32.6 years). The results of factor analysis showed that each component of the vocational constructs was distinguishable from the others. Path analysis showed that human relations in the workplace directly influenced job involvement and affective commitment both to the occupation and to the organization. Job involvement in turn directly influenced affective commitment and continuance commitment to the occupation. Job involvement also influenced affective commitment to the organization directly, and indirectly through affective commitment to the occupation. Finally, it was found that human relations in the workplace and affective commitment to the occupation positively influenced well-being; continuance commitment to the occupation was a negative influence. Theoretical and practical implications are discussed.
NASA Astrophysics Data System (ADS)
Morton, Brian Lee
The purpose of this study is to create an empirically based theoretic model of change of the use and treatment of representations of functions with the use of Connected Classroom Technology (CCT) using data previously collected for the Classroom Connectivity in Promoting Mathematics and Science Achievement (CCMS) project. Qualitative analysis of videotapes of three algebra teachers' instruction focused on different categories thought to influence teaching representations with technology: representations, discourse, technology, and decisions. Models for rating teachers low, medium, or high for each of these categories were created using a priori codes and grounded methodology. A cross case analysis was conducted after the completion of the case studies by comparing and contrasting the three cases. Data revealed that teachers' decisions shifted to incorporate the difference in student ideas/representations made visible by the CCT into their instruction and ultimately altered their orientation to mathematics teaching. The shift in orientation seemed to lead to the teachers' growth with regards to representations, discourse, and technology.
FTIR, FT-Raman, FT-NMR and quantum chemical investigations of 3-acetylcoumarin.
Arjunan, V; Sakiladevi, S; Marchewka, M K; Mohan, S
2013-05-15
3-Acetylcoumarin (3AC) was synthesised by a Knoevenagel reaction. Conformational analysis using the B3LYP method was also carried out to determine the most stable conformation of the compound. FTIR and FT-Raman spectra of 3AC have been recorded in the range 4000-400 and 4000-100 cm(-1), respectively. (1)H and (13)C NMR spectra have also been recorded. The complete vibrational assignment and analysis of the fundamental modes of the compound were carried out using the experimental FTIR and FT-Raman data and quantum mechanical studies. The experimental vibrational frequencies were compared with the wavenumbers obtained theoretically from the DFT-B3LYP/B3PW91 gradient calculations employing the standard 6-31G(**), high level 6-311++G(**) and cc-pVTZ basis sets for optimised geometry of the compound. The frontier molecular orbital energies of the compound are determined by DFT method. Copyright © 2013 Elsevier B.V. All rights reserved.
When the going gets tough: Mental toughness and its relationship with behavioural perseverance.
Gucciardi, Daniel F; Peeling, Peter; Ducker, Kagan J; Dawson, Brian
2016-01-01
This study examined the association between self-reported mental toughness and behavioural perseverance among a sample of male Australian footballers in a naturalistic context. Cross-sectional field study, with the multistage 20m shuttle run test (MST) employed as a proxy for behavioural perseverance. 330 male Australian footballers aged between 15 and 18 years (M=16.86; SD=.71) with between 2 and 14 years playing experience (M=9.32; SD=2.51) participated. Initially, footballers completed a mental toughness questionnaire, before having their height and body mass measurements taken. Subsequently, a performance testing session was completed, which included the 20m sprint, Australian football-specific agility run, vertical jump, and the MST. Bayesian estimation was employed to allow for the simultaneous examination of existing findings with our new data in a way that provides an automatic meta-analysis of evidence in this area. The analysis indicated a 95% probability that the association between mental toughness and behavioural perseverance lies between .14 and .34, even when controlling for other factors known to influence MST performance, including age, height, body mass, and years playing experience. Taken together with previous research, these findings support the theoretical proposition that persistence, effort or perseverance represents a behavioural signature of mental toughness. Copyright © 2014 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.
TASI Lectures on Cosmological Observables and String Theory
NASA Astrophysics Data System (ADS)
Silverstein, Eva
These lectures provide an updated pedagogical treatment of the theoretical structure and phenomenology of some basic mechanisms for inflation, along with an overview of the structure of cosmological uplifts of holographic duality. A full treatment of the problem requires `ultraviolet completion' because of the sensitivity of inflation to quantum gravity effects, including back reaction and non-adiabatic production of heavy degrees of freedom. Cosmological observations imply accelerated expansion of the late universe, and provide increasingly precise constraints and discovery potential on the amplitude and shape of primordial tensor and scalar perturbations, and some of their correlation functions. Most backgrounds of string theory have positive potential energy, with a rich but still highly constrained landscape of solutions. The theory contains novel mechanisms for inflation, some subject to significant observational tests, with highly UV-sensitive tensor mode measurements being a prime example along with certain shapes of primordial correlation functions. Although the detailed ultraviolet completion is not accessible experimentally, some of these mechanisms directly stimulate a more systematic analysis of the space of low energy theories and signatures relevant for analysis of data, which is sensitive to physics orders of magnitude above the energy scale of inflation as a result of long time evolution (dangerous irrelevance) and the substantial amount of data (allowing constraints on quantities with signal/noise. Portions of these lectures appeared previously in Les Houches 2013, "Post-Planck Cosmology".
Babatunde, Oyinlola T; Himburg, Susan P; Newman, Frederick L; Campa, Adriana; Dixon, Zisca
2011-01-01
To assess the effectiveness of an osteoporosis education program to improve calcium intake, knowledge, and self-efficacy in community-dwelling older Black adults. Randomized repeated measures experimental design. Churches and community-based organizations. Men and women (n = 110) 50 years old and older from 3 south Florida counties. Participants randomly assigned to either of 2 groups: Group 1 (experimental group) or Group 2 (wait-list control group). Group 1 participated in 6 weekly education program sessions immediately following baseline assessment, and Group 2 started the program following Group 1's program completion. A tested curriculum was adapted to meet the needs of the target population. Dietary calcium intake, osteoporosis knowledge, health beliefs, and self-efficacy. Descriptive and summary statistics, repeated measures analysis of variance, and regression analysis. Of the total participants, 84.6% completed the study (mean age = 70.2 years). Overall, an educational program developed with a theoretical background was associated with improvement in calcium intake, knowledge, and self-efficacy, with no effect on most health belief subscales. Assigned group was the major predictor of change in calcium intake. A theory-driven approach is valuable in improving behavior to promote bone health in this population. Health professionals should consider using more theory-driven approaches in intervention studies. Copyright © 2011 Society for Nutrition Education and Behavior. Published by Elsevier Inc. All rights reserved.
Evaluating the Sustainability of School-Based Health Centers.
Navarro, Stephanie; Zirkle, Dorothy L; Barr, Donald A
2017-01-01
The United States is facing a surge in the number of school-based health centers (SBHCs) owing to their success in delivering positive health outcomes and increasing access to care. To preserve this success, experts have developed frameworks for creating sustainable SBHCs; however, little research has affirmed or added to these models. This research seeks to analyze elements of sustainability in a case study of three SBHCs in San Diego, California, with the purpose of creating a research-based framework of SBHC sustainability to supplement expertly derived models. Using a mixed methods study design, data were collected from interviews with SBHC stakeholders, observations in SBHCs, and SBHC budgets. A grounded theory qualitative analysis and a quantitative budget analysis were completed to develop a theoretical framework for the sustainability of SBHCs. Forty-one interviews were conducted, 6 hours of observations were completed, and 3 years of SBHC budgets were analyzed to identify care coordination, community buy-in, community awareness, and SBHC partner cooperation as key themes of sustainability promoting patient retention for sustainable billing and reimbursement levels. These findings highlight the unique ways in which SBHCs gain community buy-in and awareness by becoming trusted sources of comprehensive and coordinated care within communities and among vulnerable populations. Findings also support ideas from expert models of SBHC sustainability calling for well-defined and executed community partnerships and quality coordinated care in the procurement of sustainable SBHC funding.
Finite Dimensional Approximations for Continuum Multiscale Problems
DOE Office of Scientific and Technical Information (OSTI.GOV)
Berlyand, Leonid
2017-01-24
The completed research project concerns the development of novel computational techniques for modeling nonlinear multiscale physical and biological phenomena. Specifically, it addresses the theoretical development and applications of the homogenization theory (coarse graining) approach to calculation of the effective properties of highly heterogenous biological and bio-inspired materials with many spatial scales and nonlinear behavior. This theory studies properties of strongly heterogeneous media in problems arising in materials science, geoscience, biology, etc. Modeling of such media raises fundamental mathematical questions, primarily in partial differential equations (PDEs) and calculus of variations, the subject of the PI’s research. The focus of completed researchmore » was on mathematical models of biological and bio-inspired materials with the common theme of multiscale analysis and coarse grain computational techniques. Biological and bio-inspired materials offer the unique ability to create environmentally clean functional materials used for energy conversion and storage. These materials are intrinsically complex, with hierarchical organization occurring on many nested length and time scales. The potential to rationally design and tailor the properties of these materials for broad energy applications has been hampered by the lack of computational techniques, which are able to bridge from the molecular to the macroscopic scale. The project addressed the challenge of computational treatments of such complex materials by the development of a synergistic approach that combines innovative multiscale modeling/analysis techniques with high performance computing.« less
An exploratory study of death anxiety and trainees' choice of theoretical orientation.
Belviso, Francesco; Gaubatz, Michael D
2013-01-01
This study investigated the association between therapist trainees' death anxiety and their preference for "objective" (i.e., quantitative and rational) over "subjective" (i.e., experiential and symbolic) theoretical orientations. In this correlational investigation, 303 clinical psychology and counseling trainees at a Midwestern school of professional psychology completed instruments assessing their fear of personal death and their endorsement of superordinate dimensions of psychotherapy orientations. As hypothesized, trainees who reported higher levels of death anxiety displayed a stronger preference for objective over subjective orientations, a relationship that was found in post hoc analyses to be particularly salient for male trainees. These findings suggest that trainees' death anxiety, and their attempts to control it, could influence their choice of a theoretical orientation. Potential implications for training institutions are discussed.
An exploratory study of death anxiety and trainees' choice of theoretical orientation.
Belviso, Francesco; Gaubatz, Michael D
This study investigated the association between therapist-trainees' death anxiety and their preference for "objective" (i.e., quantitative and rational) over "subjective" (i.e., experiential and symbolic) theoretical orientations. In this correlational investigation, 303 clinical psychology and counseling trainees at a Midwestern school of professional psychology completed instruments assessing their fear of personal death and their endorsement of superordinate dimensions of psychotherapy orientations. As hypothesized, trainees who reported higher levels of death anxiety displayed a stronger preference for objective over subjective orientations, a relationship that was found in post-hoc analyses to be particularly salient for male trainees. These findings suggest that trainees' death anxiety, and their attempts to control it, could influence their choice of a theoretical orientation. Potential implications for training institutions are discussed.
Theoretical Analysis of Canadian Lifelong Education Development
ERIC Educational Resources Information Center
Mukan, Natalia; Barabash, Olena; Busko, Maria
2014-01-01
In the article, the problem of Canadian lifelong education development has been studied. The main objectives of the article are defined as theoretical analysis of scientific and pedagogical literature which highlights different aspects of the research problem; periods of lifelong education development; and determination of lifelong learning role…
NASA Astrophysics Data System (ADS)
da Silva, Jorge Alberto Valle; Modesto-Costa, Lucas; de Koning, Martijn C.; Borges, Itamar; França, Tanos Celmar Costa
2018-01-01
In this work, quaternary and non-quaternary oximes designed to bind at the peripheral site of acetylcholinesterase previously inhibited by organophosphates were investigated theoretically. Some of those oximes have a large number of degrees of freedom, thus requiring an accurate method to obtain molecular geometries. For this reason, the density functional theory (DFT) was employed to refine their molecular geometries after conformational analysis and to compare their 1H and 13C nuclear magnetic resonance (NMR) theoretical signals in gas-phase and in solvent. A good agreement with experimental data was achieved and the same theoretical approach was employed to obtain the geometries in water environment for further studies.
Sibutramine characterization and solubility, a theoretical study
NASA Astrophysics Data System (ADS)
Aceves-Hernández, Juan M.; Nicolás Vázquez, Inés; Hinojosa-Torres, Jaime; Penieres Carrillo, Guillermo; Arroyo Razo, Gabriel; Miranda Ruvalcaba, René
2013-04-01
Solubility data from sibutramine (SBA) in a family of alcohols were obtained at different temperatures. Sibutramine was characterized by using thermal analysis and X-ray diffraction technique. Solubility data were obtained by the saturation method. The van't Hoff equation was used to obtain the theoretical solubility values and the ideal solvent activity coefficient. No polymorphic phenomena were found from the X-ray diffraction analysis, even though this compound is a racemic mixture of (+) and (-) enantiomers. Theoretical calculations showed that the polarisable continuum model was able to reproduce the solubility and stability of sibutramine molecule in gas phase, water and a family of alcohols at B3LYP/6-311++G (d,p) level of theory. Dielectric constant, dipolar moment and solubility in water values as physical parameters were used in those theoretical calculations for explaining that behavior. Experimental and theoretical results were compared and good agreement was obtained. Sibutramine solubility increased from methanol to 1-octanol in theoretical and experimental results.
Analysis of the Cape Cod tracer data
Ezzedine, Souheil; Rubin, Yoram
1997-01-01
An analysis of the Cape Cod test was performed using several first- and higher-order theoretical models. We compare conditional and unconditional solutions of the transport equation and employ them for analysis of the experimental data. We consider spatial moments, mass breakthrough curves, and the distribution of the solute mass in space. The concentration measurements were also analyzed using theoretical models for the expected value and variance of concentration. The theoretical models we employed are based on the spatial correlation structure of the conductivity field, without any fitting of parameters to the tracer data, and hence we can test the predictive power of the theories tested. The effects of recharge on macrodispersion are investigated, and it is shown that recharge provides a reasonable explanation for the enhanced lateral spread of the Cape Cod plume. The compendium of the experimental results presented here is useful for testing of theoretical and numerical models.
NASA Astrophysics Data System (ADS)
Sitko, Rafał
2008-11-01
Knowledge of X-ray tube spectral distribution is necessary in theoretical methods of matrix correction, i.e. in both fundamental parameter (FP) methods and theoretical influence coefficient algorithms. Thus, the influence of X-ray tube distribution on the accuracy of the analysis of thin films and bulk samples is presented. The calculations are performed using experimental X-ray tube spectra taken from the literature and theoretical X-ray tube spectra evaluated by three different algorithms proposed by Pella et al. (X-Ray Spectrom. 14 (1985) 125-135), Ebel (X-Ray Spectrom. 28 (1999) 255-266), and Finkelshtein and Pavlova (X-Ray Spectrom. 28 (1999) 27-32). In this study, Fe-Cr-Ni system is selected as an example and the calculations are performed for X-ray tubes commonly applied in X-ray fluorescence analysis (XRF), i.e., Cr, Mo, Rh and W. The influence of X-ray tube spectra on FP analysis is evaluated when quantification is performed using various types of calibration samples. FP analysis of bulk samples is performed using pure-element bulk standards and multielement bulk standards similar to the analyzed material, whereas for FP analysis of thin films, the bulk and thin pure-element standards are used. For the evaluation of the influence of X-ray tube spectra on XRF analysis performed by theoretical influence coefficient methods, two algorithms for bulk samples are selected, i.e. Claisse-Quintin (Can. Spectrosc. 12 (1967) 129-134) and COLA algorithms (G.R. Lachance, Paper Presented at the International Conference on Industrial Inorganic Elemental Analysis, Metz, France, June 3, 1981) and two algorithms (constant and linear coefficients) for thin films recently proposed by Sitko (X-Ray Spectrom. 37 (2008) 265-272).
Path Analysis Tests of Theoretical Models of Children's Memory Performance
ERIC Educational Resources Information Center
DeMarie, Darlene; Miller, Patricia H.; Ferron, John; Cunningham, Walter R.
2004-01-01
Path analysis was used to test theoretical models of relations among variables known to predict differences in children's memory--strategies, capacity, and metamemory. Children in kindergarten to fourth grade (chronological ages 5 to 11) performed different memory tasks. Several strategies (i.e., sorting, clustering, rehearsal, and self-testing)…
Spreading disease: a controversy concerning the metaphysics of disease.
D'Amico, R
1998-01-01
This article concerns the metaphysics of disease. Is disease a fixed feature of the world or a social value or preference? I argue that disease is not a value-laden concept and thus debates concerning it differ fundamentally from debates concerning health, harm, or suffering where evaluative judgements are central. I show how the so-called social constructionist view of disease has been motivated both by ethical concerns with medical practices and general theoretical doubts about scientific naturalism. If I can show that ethical concerns about medical treatment can be answered without adopting social constructionism, that leaves only the broader theoretical question of naturalism. I cannot completely answer those theoretical doubts, but I show that the theoretical motivation is less convincing when it is separated from the moral challenge often accompanying it. I conclude that a convincing defense of the non-naturalistic conception of disease is rarely attempted and proves more difficult and counter-intuitive than its proponents assume.
What Are the Differences between Happiness and Self-Esteem
ERIC Educational Resources Information Center
Lyubomirsky, Sonja; Tkach, Chris; DiMatteo, Robin M.
2006-01-01
The present study investigated theoretically and empirically derived similarities and differences between the constructs of enduring happiness and self-esteem. Participants (N = 621), retired employees ages 51-95, completed standardized measures of affect, personality, psychosocial characteristics, physical health, and demographics. The relations…
Teaching Primary Health Care: An Interdisciplinary Approach.
ERIC Educational Resources Information Center
Bezzina, Paul; Keogh, Johann J.; Keogh, Mariana
1998-01-01
Nursing and radiology students (n=15) at the University of Malta who completed an interdisciplinary module on primary health care reported they found the theoretical material applicable to practice; the module enabled them to learn about their potential role in primary health care. (SK)
NASA Astrophysics Data System (ADS)
Lugez, C. L.; Lovas, F. J.; Hougen, J. T.; Ohashi, N.
1999-03-01
Spectral data onK= 0 and 1 levels of the methanol dimer available from previous and present Fourier transform microwave measurements have been interpreted globally, using a group-theoretically derived effective Hamiltonian and corresponding tunneling matrix elements to describe the splittings arising from a large number of tunneling motions. In the present work, 302 new measurements (40K= 1-1 and 262K= 1-0 transitions) were added to the previous data set to give a total of 584 assigned transitions withJ≤ 6. As a result of the rather completeK= 0, 1 data set forJ≤ 4, the lone-pair exchange tunneling splittings were obtained experimentally. Matrix element expansions inJ(J+ 1) used in the previousK= 0 formalism were modified to apply toK> 0, essentially by making a number of real coefficients complex, as required by the generalized internal-axis-method tunneling formalism. To reduce the number of adjustable parameters to an acceptable level in both theK= 0 andK= 1 effective Hamiltonians (used in separateK= 0 andK= 1 least-squares fits), a rather large number of assumptions concerning probably negligible parameters had to be made. The present fitting results should thus be considered as providing assurance of the group-theoretical line assignments as well as a nearly quantitative global interpretation of the tunneling splittings, even though they do not yet unambiguously determine the relative contributions from all 25 group-theoretically inequivalent tunneling motions in this complex, nor do they permit quantitative extrapolation to higherKlevels.
Mitchell, Brett G; Gardner, Anne
2014-03-01
To present a discussion on theoretical frameworks in infection prevention and control. Infection prevention and control programmes have been in place for several years in response to the incidence of healthcare-associated infections and their associated morbidity and mortality. Theoretical frameworks play an important role in formalizing the understanding of infection prevention activities. Discussion paper. A literature search using electronic databases was conducted for published articles in English addressing theoretical frameworks in infection prevention and control between 1980-2012. Nineteen papers that included a reference to frameworks were identified in the review. A narrative analysis of these papers was completed. Two models were identified and neither included the role of surveillance. To reduce the risk of acquiring a healthcare-associated infection, a multifaceted approach to infection prevention is required. One key component in this approach is surveillance. The review identified two infection prevention and control frameworks, yet these are rarely applied in infection prevention and control programmes. Only one framework considered the multifaceted approach required for infection prevention. It did not, however, incorporate the role of surveillance. We present a framework that incorporates the role of surveillance into a biopsychosocial approach to infection prevention and control. Infection prevention and control programmes and associated research are led primarily by nurses. There is a need for an explicit infection prevention and control framework incorporating the important role that surveillance has in infection prevention activities. This study presents one framework for further critique and discussion. © 2013 John Wiley & Sons Ltd.
ERIC Educational Resources Information Center
Zhu, Wenzhong; Liu, Dan
2014-01-01
Based on a review of the literature on ESP and needs analysis, this paper is intended to offer some theoretical supports and inspirations for BE instructors to develop BE curricula for business contexts. It discusses how the theory of need analysis can be used in Business English curriculum design, and proposes some principles of BE curriculum…
HICOSMO: cosmology with a complete sample of galaxy clusters - II. Cosmological results
NASA Astrophysics Data System (ADS)
Schellenberger, G.; Reiprich, T. H.
2017-10-01
The X-ray bright, hot gas in the potential well of a galaxy cluster enables systematic X-ray studies of samples of galaxy clusters to constrain cosmological parameters. HIFLUGCS consists of the 64 X-ray brightest galaxy clusters in the Universe, building up a local sample. Here, we utilize this sample to determine, for the first time, individual hydrostatic mass estimates for all the clusters of the sample and, by making use of the completeness of the sample, we quantify constraints on the two interesting cosmological parameters, Ωm and σ8. We apply our total hydrostatic and gas mass estimates from the X-ray analysis to a Bayesian cosmological likelihood analysis and leave several parameters free to be constrained. We find Ωm = 0.30 ± 0.01 and σ8 = 0.79 ± 0.03 (statistical uncertainties, 68 per cent credibility level) using our default analysis strategy combining both a mass function analysis and the gas mass fraction results. The main sources of biases that we correct here are (1) the influence of galaxy groups (incompleteness in parent samples and differing behaviour of the Lx-M relation), (2) the hydrostatic mass bias, (3) the extrapolation of the total mass (comparing various methods), (4) the theoretical halo mass function and (5) other physical effects (non-negligible neutrino mass). We find that galaxy groups introduce a strong bias, since their number density seems to be over predicted by the halo mass function. On the other hand, incorporating baryonic effects does not result in a significant change in the constraints. The total (uncorrected) systematic uncertainties (∼20 per cent) clearly dominate the statistical uncertainties on cosmological parameters for our sample.
Theoretical and experimental studies relevant to interpretation of auroral emissions
NASA Technical Reports Server (NTRS)
Keffer, Charles E.
1992-01-01
The results obtained in the second year of a three year collaborative effort with MSFC are summarized. A succession of experimental studies was completed to determine the effects of the natural and induced space vehicle environment on the measurement of auroral images from space-based platforms. In addition, a global model which incorporates both auroral and dayglow emission sources is being developed to allow interpretation of measured auroral emissions. A description of work completed on these two tasks is presented.
Magnetospheric radio and plasma wave research - 1987-1990
NASA Technical Reports Server (NTRS)
Kurth, W. S.
1991-01-01
This review covers research performed in the area of magnetospheric plasma waves and wave-particle interactions as well as magnetospheric radio emissions. The report focuses on the near-completion of the discovery phase of radio and plasma wave phenomena in the planetary magnetospheres with the successful completion of the Voyager 2 encounters of Neptune and Uranus. Consideration is given to the advances made in detailed studies and theoretical investigations of radio and plasma wave phenomena in the terrestrial magnetosphere or in magnetospheric plasmas in general.
Munar, Wolfgang; Wahid, Syed S; Curry, Leslie
2018-01-03
Background . Improving performance of primary care systems in low- and middle-income countries (LMICs) may be a necessary condition for achievement of universal health coverage in the age of Sustainable Development Goals. The Salud Mesoamerica Initiative (SMI), a large-scale, multi-country program that uses supply-side financial incentives directed at the central-level of governments, and continuous, external evaluation of public, health sector performance to induce improvements in primary care performance in eight LMICs. This study protocol seeks to explain whether and how these interventions generate program effects in El Salvador and Honduras. Methods . This study presents the protocol for a study that uses a realist evaluation approach to develop a preliminary program theory that hypothesizes the interactions between context, interventions and the mechanisms that trigger outcomes. The program theory was completed through a scoping review of relevant empirical, peer-reviewed and grey literature; a sense-making workshop with program stakeholders; and content analysis of key SMI documents. The study will use a multiple case-study design with embedded units with contrasting cases. We define as a case the two primary care systems of Honduras and El Salvador, each with different context characteristics. Data will be collected through in-depth interviews with program actors and stakeholders, documentary review, and non-participatory observation. Data analysis will use inductive and deductive approaches to identify causal patterns organized as 'context, mechanism, outcome' configurations. The findings will be triangulated with existing secondary, qualitative and quantitative data sources, and contrasted against relevant theoretical literature. The study will end with a refined program theory. Findings will be published following the guidelines generated by the Realist and Meta-narrative Evidence Syntheses study (RAMESES II). This study will be performed contemporaneously with SMI's mid-term stage of implementation. Of the methods described, the preliminary program theory has been completed. Data collection, analysis and synthesis remain to be completed.
NASA Astrophysics Data System (ADS)
De Marchi, G.; Paresce, F.; Straniero, O.; Prada Moroni, P. G.
2004-03-01
Very deep images of the Galactic globular cluster M 4 (NGC 6121) through the F606W and F814W filters were taken in 2001 with the WFPC2 on board the HST. A first published analysis of this data set (Richer et al. \\cite{Richer2002}) produced the result that the age of M 4 is 12.7± 0.7 Gyr (Hansen et al. \\cite{Hansen2002}), thus setting a robust lower limit to the age of the universe. In view of the great astronomical importance of getting this number right, we have subjected the same data set to the simplest possible photometric analysis that completely avoids uncertain assumptions about the origin of the detected sources. This analysis clearly reveals both a thin main sequence, from which can be deduced the deepest statistically complete mass function yet determined for a globular cluster, and a white dwarf (WD) sequence extending all the way down to the 5 \\sigma detection limit at I ≃ 27. The WD sequence is abruptly terminated at exactly this limit as expected by detection statistics. Using our most recent theoretical WD models (Prada Moroni & Straniero \\cite{Prada2002}) to obtain the expected WD sequence for different ages in the observed bandpasses, we find that the data so far obtained do not reach the peak of the WD luminosity function, thus only allowing one to set a lower limit to the age of M 4 of ˜9 Gyr. Thus, the problem of determining the absolute age of a globular cluster and, therefore, the onset of GC formation with cosmologically significant accuracy remains completely open. Only observations several magnitudes deeper than the limit obtained so far would allow one to approach this objective. Based on observations with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by AURA for NASA under contract NAS5-26555.
Munar, Wolfgang; Wahid, Syed S.; Curry, Leslie
2018-01-01
Background. Improving performance of primary care systems in low- and middle-income countries (LMICs) may be a necessary condition for achievement of universal health coverage in the age of Sustainable Development Goals. The Salud Mesoamerica Initiative (SMI), a large-scale, multi-country program that uses supply-side financial incentives directed at the central-level of governments, and continuous, external evaluation of public, health sector performance to induce improvements in primary care performance in eight LMICs. This study protocol seeks to explain whether and how these interventions generate program effects in El Salvador and Honduras. Methods. This study presents the protocol for a study that uses a realist evaluation approach to develop a preliminary program theory that hypothesizes the interactions between context, interventions and the mechanisms that trigger outcomes. The program theory was completed through a scoping review of relevant empirical, peer-reviewed and grey literature; a sense-making workshop with program stakeholders; and content analysis of key SMI documents. The study will use a multiple case-study design with embedded units with contrasting cases. We define as a case the two primary care systems of Honduras and El Salvador, each with different context characteristics. Data will be collected through in-depth interviews with program actors and stakeholders, documentary review, and non-participatory observation. Data analysis will use inductive and deductive approaches to identify causal patterns organized as ‘context, mechanism, outcome’ configurations. The findings will be triangulated with existing secondary, qualitative and quantitative data sources, and contrasted against relevant theoretical literature. The study will end with a refined program theory. Findings will be published following the guidelines generated by the Realist and Meta-narrative Evidence Syntheses study (RAMESES II). This study will be performed contemporaneously with SMI’s mid-term stage of implementation. Of the methods described, the preliminary program theory has been completed. Data collection, analysis and synthesis remain to be completed. PMID:29431181
Investigation into mechanical properties of bone and its main constituents
NASA Astrophysics Data System (ADS)
Evdokimenko, Ekaterina
Bone is a hierarchically structured natural composite material, consisting of organic phase (type-I collagen), inorganic phase (hydroxyapatite), and water. Studies of the two main bone constituents, utilizing controlled demineralization and deproteinization, can shed light on mineral-collagen interaction which makes bone such a unique biological material. This knowledge is necessary for computational analysis of bone structure to identify preferential sites in the collagen matrix and mineral network that degrade more easily. The main goal of this work is to develop a comprehensive picture of mechanical properties of bone and its main constituents. Following the Introduction, Chapter 2 presents an investigation of microstructure and compressive mechanical properties of bovine femur cortical bone carried out on completely demineralized, completely deproteinized, and untreated bone samples in three anatomical directions. Anisotropic nature of bone was clearly identified in all cases. Extra levels of porosity along with microstructural differences for the three directions were found to be the main sources of the anisotropy. In Chapter 3, a new theoretical model of cortical and trabecular bone as composite materials with hierarchical structure spanning from nanometer (collagen-mineral) level to millimeter (bone) level was developed. Compression testing was performed on untreated, demineralized, and deproteinized cortical and trabecular bovine femur bone samples to verify the model. The experimental data were compared with theoretical predictions; excellent agreement was found between the theory and experiments for all bone phases. Optical microscopy, scanning electron microscopy, and micro-computed tomography techniques were applied to characterize the structure of the samples at multiple length scales and provide further inputs for the modeling. Chapter 4 presents a comparative study of mechanical properties, microstructure, and porosity of mature and young bovine femur cortical bone. It was found that the amount of porosity decreases, while the microhardness increases with maturation. Osteoporotic degradation of trabecular bone elasticity, described in Chapter 5, was modeled using a cellular mechanics approach. Evolution equations for elastic modulus of bone in terms of those of mineral and protein trabeculae and in terms of demineralized and deproteinized bones were formulated and verified by the analysis of compressive properties of bovine femur trabecular bone.
Overcoming Barriers: Adolescents’ Experiences Using a Mobile Phone Dietary Assessment App
Svensson, Åsa; Magnusson, Maria
2016-01-01
Background The use of new technology has the potential to increase participation rates in dietary studies and improve the validity of collected dietary data. However, to evaluate the usability of developed dietary methods, qualitative studies of participants’ experiences and perceptions are needed. Objective To explore adolescents’ experiences using a newly developed mobile phone dietary assessment app, with a focus on factors that could affect their recording of dietary intake. Methods Focus group interviews were conducted with 75 participants who had used a newly developed mobile phone dietary assessment app in a quantitative evaluation study. The interviews were analyzed using qualitative content analysis and the theoretical framework of Self Determination Theory was applied. Results The adolescents’ use of the mobile phone dietary assessment app was characterized by their struggle to overcome several perceived barriers. Facilitators that helped adolescents complete the method were also identified. Motivation was found to be an important facilitator, and intrinsically motivated participants completed the method because they found it fun to use. The autonomous extrinsically motivated participants completed the method for the greater good, in order to contribute to the study. The controlled extrinsically motivated participants completed the method to get a reward or avoid punishment. Amotivated participants did not complete the method. More motivated participants were assumed to be more able to overcome barriers and needed less facilitators. Conclusions Future studies that examine the recording of food intake should include systematic efforts that aim to minimize identified barriers and promote identified facilitators. Further research should specifically aim at studying methods for (and effects of) increasing intrinsic motivation by supporting autonomy, competence, and relatedness among adolescents asked to participate in dietary studies. PMID:27473462
Altschuler, Ted S; Molholm, Sophie; Butler, John S; Mercier, Manuel R; Brandwein, Alice B; Foxe, John J
2014-04-15
The adult human visual system can efficiently fill-in missing object boundaries when low-level information from the retina is incomplete, but little is known about how these processes develop across childhood. A decade of visual-evoked potential (VEP) studies has produced a theoretical model identifying distinct phases of contour completion in adults. The first, termed a perceptual phase, occurs from approximately 100-200 ms and is associated with automatic boundary completion. The second is termed a conceptual phase occurring between 230 and 400 ms. The latter has been associated with the analysis of ambiguous objects which seem to require more effort to complete. The electrophysiological markers of these phases have both been localized to the lateral occipital complex, a cluster of ventral visual stream brain regions associated with object-processing. We presented Kanizsa-type illusory contour stimuli, often used for exploring contour completion processes, to neurotypical persons ages 6-31 (N=63), while parametrically varying the spatial extent of these induced contours, in order to better understand how filling-in processes develop across childhood and adolescence. Our results suggest that, while adults complete contour boundaries in a single discrete period during the automatic perceptual phase, children display an immature response pattern-engaging in more protracted processing across both timeframes and appearing to recruit more widely distributed regions which resemble those evoked during adult processing of higher-order ambiguous figures. However, children older than 5years of age were remarkably like adults in that the effects of contour processing were invariant to manipulation of contour extent. Copyright © 2013 Elsevier Inc. All rights reserved.
Linear and nonlinear analysis of fluid slosh dampers
NASA Astrophysics Data System (ADS)
Sayar, B. A.; Baumgarten, J. R.
1982-11-01
A vibrating structure and a container partially filled with fluid are considered coupled in a free vibration mode. To simplify the mathematical analysis, a pendulum model to duplicate the fluid motion and a mass-spring dashpot representing the vibrating structure are used. The equations of motion are derived by Lagrange's energy approach and expressed in parametric form. For a wide range of parametric values the logarithmic decrements of the main system are calculated from theoretical and experimental response curves in the linear analysis. However, for the nonlinear analysis the theoretical and experimental response curves of the main system are compared. Theoretical predictions are justified by experimental observations with excellent agreement. It is concluded finally that for a proper selection of design parameters, containers partially filled with viscous fluids serve as good vibration dampers.
Is it really theoretical? A review of sampling in grounded theory studies in nursing journals.
McCrae, Niall; Purssell, Edward
2016-10-01
Grounded theory is a distinct method of qualitative research, where core features are theoretical sampling and constant comparative analysis. However, inconsistent application of these activities has been observed in published studies. This review assessed the use of theoretical sampling in grounded theory studies in nursing journals. An adapted systematic review was conducted. Three leading nursing journals (2010-2014) were searched for studies stating grounded theory as the method. Sampling was assessed using a concise rating tool. A high proportion (86%) of the 134 articles described an iterative process of data collection and analysis. However, half of the studies did not demonstrate theoretical sampling, with many studies declaring or indicating a purposive sampling approach throughout. Specific reporting guidelines for grounded theory studies should be developed to ensure that study reports describe an iterative process of fieldwork and theoretical development. © 2016 John Wiley & Sons Ltd.
Theoretical analysis of fused tapered side-pumping combiner for all-fiber lasers and amplifiers
NASA Astrophysics Data System (ADS)
Lei, Chengmin; Chen, Zilun; Leng, Jinyong; Gu, Yanran; Hou, Jing
2017-05-01
We report detailed theoretical analysis on the influence of the fused depth, launch mode and taper ratio on the performance of side-pumping combiner. The theoretical analysis indicates that the coupling efficiency and loss mechanism of the combiner is closely related to the fused depth, tapering ratio and the launch mode. Experimentally, we fabricate combiners consisting of two pump fibers (220/242 μm, NA=0.22) and a signal fiber (20/400 μm, NA=0.46). The combined pump coupling efficiency of two pump port is 97.2% with the maximum power handling of 1.8 kW and the insertion signal loss is less than 3%.
Core self-evaluation as a predictor of strength training adoption in older adults.
Baker, Michael K; Kennedy, David J; Bohle, Philip L; Campbell, Deena; Wiltshire, James H; Singh, Maria A Fiatarone
2011-01-01
Progressive resistance training (PRT) counteracts sarcopenia and has been demonstrated to improve physical function and quality of life in older adults. Despite the clear benefits of PRT, participation remains low. The core self-evaluation (CSE) construct is theoretically antecedent to four personality traits: locus of control, self-esteem, neuroticism (emotional stability), and generalized self-efficacy. We have examined the association of CSE with exercise adoption among older adults invited to participate in a PRT trial. We hypothesized that CSE would positively predict adoption of PRT. All residents of two retirement communities were invited to complete questionnaires with items on demographics, physical activity, CSE, and general health. Following completion of questionnaires, residents were invited to take part in an on-site, 10-week randomized controlled trial of a PRT-based exercise trial. Thirty-eight of 358 residents (63.2% women; 76.6±6.1 year; range 58-92) enrolled and 118 residents completed the questionnaires. Multiple regression analysis predicting PRT adoption indicated that the demographic variables accounted for 38% of the variance. Inclusion of CSE (β=.405) accounted for an additional 10% of the variance in PRT adoption. CSE was predictive of PRT adoption in this cohort, adding significantly to the predictive efficacy of known demographic predictors. This is the first study to show that CSE may influence adoption of PRT in any cohort. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.
Multiphase complete exchange: A theoretical analysis
NASA Technical Reports Server (NTRS)
Bokhari, Shahid H.
1993-01-01
Complete Exchange requires each of N processors to send a unique message to each of the remaining N-1 processors. For a circuit switched hypercube with N = 2(sub d) processors, the Direct and Standard algorithms for Complete Exchange are optimal for very large and very small message sizes, respectively. For intermediate sizes, a hybrid Multiphase algorithm is better. This carries out Direct exchanges on a set of subcubes whose dimensions are a partition of the integer d. The best such algorithm for a given message size m could hitherto only be found by enumerating all partitions of d. The Multiphase algorithm is analyzed assuming a high performance communication network. It is proved that only algorithms corresponding to equipartitions of d (partitions in which the maximum and minimum elements differ by at most 1) can possibly be optimal. The run times of these algorithms plotted against m form a hull of optimality. It is proved that, although there is an exponential number of partitions, (1) the number of faces on this hull is Theta(square root of d), (2) the hull can be found in theta(square root of d) time, and (3) once it has been found, the optimal algorithm for any given m can be found in Theta(log d) time. These results provide a very fast technique for minimizing communication overhead in many important applications, such as matrix transpose, Fast Fourier transform, and ADI.
NASA Technical Reports Server (NTRS)
Liang, Shoudan
2000-01-01
Our research effort has produced nine publications in peer-reviewed journals listed at the end of this report. The work reported here are in the following areas: (1) genetic network modeling; (2) autocatalytic model of pre-biotic evolution; (3) theoretical and computational studies of strongly correlated electron systems; (4) reducing thermal oscillations in atomic force microscope; (5) transcription termination mechanism in prokaryotic cells; and (6) the low glutamine usage in thennophiles obtained by studying completely sequenced genomes. We discuss the main accomplishments of these publications.
Women's Roles and Vulnerability to Depression.
ERIC Educational Resources Information Center
Haussmann, Monika Johanna
Research has confirmed the prevalence of depression in women, based on theoretical explanations that encompass genetic/endocrinological factors, the learned helplessness model, the cognitive model of depression, the effects of marital and occupational roles, and/or social discrimination. Women (N=215) completed a questionnaire which examined…
DOT National Transportation Integrated Search
2014-05-01
Different problems in straight skewed steel I-girder bridges are often associated with the methods used for detailing the cross-frames. Use of theoretical terms to describe these detailing methods and absence of complete and simplified design approac...
[Structuralist reading of radiologic images].
Wackenheim, A
1984-02-01
The author suggests analysing the radiological image according to classical principles of structuralism, gestaltism, semiology, semantics. He describes applications in routine radiology: perception of complete theoretical displacement of parts of the image, phenomenology of three images (A-B-C) in theory and exams, mistake in perception by analogy.
Sampling Assumptions in Inductive Generalization
ERIC Educational Resources Information Center
Navarro, Daniel J.; Dry, Matthew J.; Lee, Michael D.
2012-01-01
Inductive generalization, where people go beyond the data provided, is a basic cognitive capability, and it underpins theoretical accounts of learning, categorization, and decision making. To complete the inductive leap needed for generalization, people must make a key "sampling" assumption about how the available data were generated.…
Theory of electronically phased coherent beam combination without a reference beam
NASA Astrophysics Data System (ADS)
Shay, Thomas M.
2006-12-01
The first theory for two novel coherent beam combination architectures that are the first electronic beam combination architectures that completely eliminate the need for a separate reference beam are presented. Detailed theoretical models are developed and presented for the first time.
Caldwell Hooper, Ann E.; Thayer, Rachel E.; Magnan, Renee E.; Bryan, Angela D.
2013-01-01
The current study examined the relationships among marijuana dependence, a theoretical model of condom use intentions, and subsequent condom use behavior in justice-involved adolescents. Participants completed baseline measures of prior sexual and substance use behavior. Of the original 720 participants, 649 (90.13 %) completed follow-up measures 6 months later. There were high levels of marijuana use (58.7 % met criteria for dependence) and risky sexual behavior among participants. Baseline model constructs were associated with condom use intentions, and intentions were a significant predictor of condom use at follow-up. Marijuana dependence did not significantly influence the relationships between model constructs, nor did it moderate the relationship of model constructs with subsequent condom use. Findings suggest that the theoretical model of condom use intentions is equally valid regardless of marijuana dependence status, suggesting that interventions to reduce sexual risk behavior among both marijuana dependent and non-dependent justice-involved adolescents can be appropriately based on the model. PMID:23370834
Self-Healing Nanotextured Vascular-like Materials: Mode I Crack Propagation.
Lee, Min Wook; Sett, Soumyadip; An, Seongpil; Yoon, Sam S; Yarin, Alexander L
2017-08-16
Here, we investigate crack propagation initiated from an initial notch in a self-healing material. The crack propagation in the core-shell nanofiber mats formed by coelectrospinning and the composites reinforced by them is in focus. All samples are observed from the crack initiation until complete failure. Due to the short-time experiments done on purpose, the resin and cure released from the cores of the core-shell nanofibers could not achieve a complete curing and stop crack growth, especially given the fact that no heating was used. The aim is to elucidate their effect on the rate of crack propagation. The crack propagation speed in polyacrylonitrile (PAN)-resin-cure nanofiber mats (with PAN being the polymer in the shell) was remarkably lower than that in the corresponding monolithic PAN nanofiber mat, down to 10%. The nanofiber mats were also encased in polydimethylsiloxane (PDMS) matrix to form composites. The crack shape and propagation in the composite samples were studied experimentally and analyzed theoretically, and the theoretical results revealed agreement with the experimental data.
NASA Astrophysics Data System (ADS)
Boichenko, Stepan
2018-04-01
We theoretically study laser-scanning confocal fluorescence microscopy using elliptically polarized cylindrical vector excitation light as a tool for visualization of arbitrarily oriented single quantum dipole emitters located (1) near planar surfaces enhancing fluorescence, (2) in a thin supported polymer film, (3) in a freestanding polymer film, and (4) in a dielectric planar microcavity. It is shown analytically that by using a tightly focused azimuthally polarized beam, it is possible to exclude completely the orientational dependence of the image intensity maximum of a quantum emitter that absorbs light as a pair of incoherent independent linear dipoles. For linear dipole quantum emitters, the orientational independence degree higher than 0.9 can normally be achieved (this quantity equal to 1 corresponds to completely excluded orientational dependence) if the collection efficiency of the microscope objective and the emitter's total quantum yield are not strongly orientationally dependent. Thus, the visualization of arbitrarily oriented single quantum emitters by means of the studied technique can be performed quite efficiently.
Plasmonic hot carrier dynamics in solid-state and chemical systems for energy conversion
Narang, Prineha; Sundararaman, Ravishankar; Atwater, Harry A.
2016-06-11
Surface plasmons provide a pathway to efficiently absorb and confine light in metallic nanostructures, thereby bridging photonics to the nano scale. The decay of surface plasmons generates energetic ‘hot’ carriers, which can drive chemical reactions or be injected into semiconductors for nano-scale photochemical or photovoltaic energy conversion. Novel plasmonic hot carrier devices and architectures continue to be demonstrated, but the complexity of the underlying processes make a complete microscopic understanding of all the mechanisms and design considerations for such devices extremely challenging.Here,we review the theoretical and computational efforts to understand and model plasmonic hot carrier devices.We split the problem intomore » three steps: hot carrier generation, transport and collection, and review theoretical approaches with the appropriate level of detail for each step along with their predictions. As a result, we identify the key advances necessary to complete the microscopic mechanistic picture and facilitate the design of the next generation of devices and materials for plasmonic energy conversion.« less
NASA Technical Reports Server (NTRS)
Saleeb, Atef F.; Li, Wei
1995-01-01
This two-part report is concerned with the development of a general framework for the implicit time-stepping integrators for the flow and evolution equations in generalized viscoplastic models. The primary goal is to present a complete theoretical formulation, and to address in detail the algorithmic and numerical analysis aspects involved in its finite element implementation, as well as to critically assess the numerical performance of the developed schemes in a comprehensive set of test cases. On the theoretical side, the general framework is developed on the basis of the unconditionally-stable, backward-Euler difference scheme as a starting point. Its mathematical structure is of sufficient generality to allow a unified treatment of different classes of viscoplastic models with internal variables. In particular, two specific models of this type, which are representative of the present start-of-art in metal viscoplasticity, are considered in applications reported here; i.e., fully associative (GVIPS) and non-associative (NAV) models. The matrix forms developed for both these models are directly applicable for both initially isotropic and anisotropic materials, in general (three-dimensional) situations as well as subspace applications (i.e., plane stress/strain, axisymmetric, generalized plane stress in shells). On the computational side, issues related to efficiency and robustness are emphasized in developing the (local) interative algorithm. In particular, closed-form expressions for residual vectors and (consistent) material tangent stiffness arrays are given explicitly for both GVIPS and NAV models, with their maximum sizes 'optimized' to depend only on the number of independent stress components (but independent of the number of viscoplastic internal state parameters). Significant robustness of the local iterative solution is provided by complementing the basic Newton-Raphson scheme with a line-search strategy for convergence. In the present first part of the report, we focus on the theoretical developments, and discussions of the results of numerical-performance studies using the integration schemes for GVIPS and NAV models.
NASA Technical Reports Server (NTRS)
Sadler, S. G.
1972-01-01
A mathematical model and computer program were implemented to study the main rotor free wake geometry effects on helicopter rotor blade air loads and response in steady maneuvers. The theoretical formulation and analysis of results are presented.
Theoretical Notes on the Sociological Analysis of School Reform Networks
ERIC Educational Resources Information Center
Ladwig, James G.
2014-01-01
Nearly two decades ago, Ladwig outlined the theoretical and methodological implications of Bourdieu's concept of the social field for sociological analyses of educational policy and school reform. The current analysis extends this work to consider the sociological import of one of the most ubiquitous forms of educational reform found around…
Researching Education Policy in a Globalized World: Theoretical and Methodological Considerations
ERIC Educational Resources Information Center
Lingard, Bob
2009-01-01
This paper shows how globalization has given rise to a number of new theoretical and methodological issues for doing education policy analysis linked to globalization's impact within critical social science. Critical policy analysis has always required critical "reflexivity" and awareness of the "positionality" of the policy analyst. However, as…
Mode Deactivation Therapy (MDT) Family Therapy: A Theoretical Case Analysis
ERIC Educational Resources Information Center
Apsche, J. A.; Ward Bailey, S. R.
2004-01-01
This case study presents a theoretical analysis of implementing mode deactivation therapy (MDT) (Apsche & Ward Bailey, 2003) family therapy with a 13 year old Caucasian male. MDT is a form of cognitive behavioral therapy (CBT) that combines the balance of dialectical behavior therapy (DBT) (Linehan, 1993), the importance of perception from…
Au36(SePh)24 nanomolecules: synthesis, optical spectroscopy and theoretical analysis.
Rambukwella, Milan; Chang, Le; Ravishanker, Anish; Fortunelli, Alessandro; Stener, Mauro; Dass, Amala
2018-05-16
Here, we report the synthesis of selenophenol (HSePh) protected Au36(SePh)24 nanomolecules via a ligand-exchange reaction of 4-tert-butylbenzenethiol (HSPh-tBu) protected Au36(SPh-tBu)24 with selenophenol, and its spectroscopic and theoretical analysis. Matrix assisted laser desorption ionization (MALDI) mass spectrometry, electrospray ionization (ESI) mass spectrometry and optical characterization confirm that the composition of the as synthesized product is predominantly Au36(SePh)24 nanomolecules. Size exclusion chromatography (SEC) was employed to isolate the Au36(SePh)24 and temperature dependent optical absorption studies and theoretical analysis were performed. Theoretically, an Independent Component Maps of Oscillator Strength (ICM-OS) analysis of simulated spectra shows that the enhancement in absorption intensity in Au36(SePh)24 with respect to Au36(SPh)24 can be ascribed to the absence of interference and/or increased long-range coupling between interband metal core and ligand excitations. This work demonstrates and helps to understand the effect of Au-Se bridging on the properties of gold nanomolecules.
Self-assembly in Dipolar Fluids
NASA Astrophysics Data System (ADS)
Ronti, Michela; Kantorovich, Sofia
We are studying low temperature structural transitions in dipolar hard spheres (DHS), combining grand-canonical Monte Carlo simulations and direct analytical theoretical calculations. DHS is characterized by long-range anisotropic interactions: it consists of a point dipole at the center of a hard sphere. We are interested in low temperature and low density phase behaviour of DHS systems. From a theoretical point of view the process of self-assembly is not responsible for a phase transition; this belief was completely reverted by theoretical studies showing that the process of self-assembly is alone capable to induce phase transition. On the other hand in the last years it was proved that no sign of critical behaviour is observed, implementing efficient and tailored Monte Carlo algorithms. Moreover a theoretical approach based on Density Functional Theory was developed: a series of structural transitions were discovered providing evidence of a hierarchy in the structures on cooling. We are performing free-energy calculations in order to draw the phase diagram of DHS model. Comparing the numerical results with the theoretical ones shed light on the scenario of temperature induced structural transitions in magnetic nanocolloids. Etn-COLLDENSE (H2020-MCSA-ITN-2014, Grant No. 642774).
Ormerod, Marcus; Newton, Rita
2018-01-01
Modifying the home environments of older people as they age in place is a well-established health and social care intervention. Using design and construction methods to redress any imbalance caused by the ageing process or disability within the home environment, occupational therapists are seen as the experts in this field of practice. However, the process used by occupational therapists when modifying home environments has been criticised for being disorganised and not founded on theoretical principles and concepts underpinning the profession. To address this issue, research was conducted to develop a design and construction process protocol specifically for home modifications. A three-stage approach was taken for the analysis of qualitative data generated from an online survey, completed by 135 occupational therapists in the UK. Using both the existing occupational therapy intervention process model and the design and construction process protocol as the theoretical frameworks, a 4-phase, 9-subphase design and construction process protocol for home modifications was developed. Overall, the study is innovative in developing the first process protocol for home modifications, potentially providing occupational therapists with a systematic and effective approach to the design and delivery of home modification services for older and disabled people. PMID:29682348
Russell, Rachel; Ormerod, Marcus; Newton, Rita
2018-01-01
Modifying the home environments of older people as they age in place is a well-established health and social care intervention. Using design and construction methods to redress any imbalance caused by the ageing process or disability within the home environment, occupational therapists are seen as the experts in this field of practice. However, the process used by occupational therapists when modifying home environments has been criticised for being disorganised and not founded on theoretical principles and concepts underpinning the profession. To address this issue, research was conducted to develop a design and construction process protocol specifically for home modifications. A three-stage approach was taken for the analysis of qualitative data generated from an online survey, completed by 135 occupational therapists in the UK. Using both the existing occupational therapy intervention process model and the design and construction process protocol as the theoretical frameworks, a 4-phase, 9-subphase design and construction process protocol for home modifications was developed. Overall, the study is innovative in developing the first process protocol for home modifications, potentially providing occupational therapists with a systematic and effective approach to the design and delivery of home modification services for older and disabled people.
Spence Laschinger, Heather K; Leiter, Michael P
2006-05-01
To test a theoretical model of professional nurse work environments linking conditions for professional nursing practice to burnout and, subsequently, patient safety outcomes. The 2004 Institute of Medicine report raised serious concerns about the impact of hospital restructuring on nursing work environments and patient safety outcomes. Few studies have used a theoretical framework to study the nature of the relationships between nursing work environments and patient safety outcomes. Hospital-based nurses in Canada (N = 8,597) completed measures of worklife (Practice Environment Scale of the Nursing Work Index), burnout (Maslach Burnout Inventory-Human Service Scale), and their report of frequency of adverse patient events. Structural equation modeling analysis supported an extension of Leiter and Laschinger's Nursing Worklife Model. Nursing leadership played a fundamental role in the quality of worklife regarding policy involvement, staffing levels, support for a nursing model of care (vs medical), and nurse/physician relationships. Staffing adequacy directly affected emotional exhaustion, and use of a nursing model of care had a direct effect on nurses' personal accomplishment. Both directly affected patient safety outcomes. The results suggest that patient safety outcomes are related to the quality of the nursing practice work environment and nursing leadership's role in changing the work environment to decrease nurse burnout.
Analysis of entropy extraction efficiencies in random number generation systems
NASA Astrophysics Data System (ADS)
Wang, Chao; Wang, Shuang; Chen, Wei; Yin, Zhen-Qiang; Han, Zheng-Fu
2016-05-01
Random numbers (RNs) have applications in many areas: lottery games, gambling, computer simulation, and, most importantly, cryptography [N. Gisin et al., Rev. Mod. Phys. 74 (2002) 145]. In cryptography theory, the theoretical security of the system calls for high quality RNs. Therefore, developing methods for producing unpredictable RNs with adequate speed is an attractive topic. Early on, despite the lack of theoretical support, pseudo RNs generated by algorithmic methods performed well and satisfied reasonable statistical requirements. However, as implemented, those pseudorandom sequences were completely determined by mathematical formulas and initial seeds, which cannot introduce extra entropy or information. In these cases, “random” bits are generated that are not at all random. Physical random number generators (RNGs), which, in contrast to algorithmic methods, are based on unpredictable physical random phenomena, have attracted considerable research interest. However, the way that we extract random bits from those physical entropy sources has a large influence on the efficiency and performance of the system. In this manuscript, we will review and discuss several randomness extraction schemes that are based on radiation or photon arrival times. We analyze the robustness, post-processing requirements and, in particular, the extraction efficiency of those methods to aid in the construction of efficient, compact and robust physical RNG systems.
Asinari, Pietro
2009-11-01
A finite difference lattice Boltzmann scheme for homogeneous mixture modeling, which recovers Maxwell-Stefan diffusion model in the continuum limit, without the restriction of the mixture-averaged diffusion approximation, was recently proposed [P. Asinari, Phys. Rev. E 77, 056706 (2008)]. The theoretical basis is the Bhatnagar-Gross-Krook-type kinetic model for gas mixtures [P. Andries, K. Aoki, and B. Perthame, J. Stat. Phys. 106, 993 (2002)]. In the present paper, the recovered macroscopic equations in the continuum limit are systematically investigated by varying the ratio between the characteristic diffusion speed and the characteristic barycentric speed. It comes out that the diffusion speed must be at least one order of magnitude (in terms of Knudsen number) smaller than the barycentric speed, in order to recover the Navier-Stokes equations for mixtures in the incompressible limit. Some further numerical tests are also reported. In particular, (1) the solvent and dilute test cases are considered, because they are limiting cases in which the Maxwell-Stefan model reduces automatically to Fickian cases. Moreover, (2) some tests based on the Stefan diffusion tube are reported for proving the complete capabilities of the proposed scheme in solving Maxwell-Stefan diffusion problems. The proposed scheme agrees well with the expected theoretical results.
Optimal Tikhonov Regularization in Finite-Frequency Tomography
NASA Astrophysics Data System (ADS)
Fang, Y.; Yao, Z.; Zhou, Y.
2017-12-01
The last decade has witnessed a progressive transition in seismic tomography from ray theory to finite-frequency theory which overcomes the resolution limit of the high-frequency approximation in ray theory. In addition to approximations in wave propagation physics, a main difference between ray-theoretical tomography and finite-frequency tomography is the sparseness of the associated sensitivity matrix. It is well known that seismic tomographic problems are ill-posed and regularizations such as damping and smoothing are often applied to analyze the tradeoff between data misfit and model uncertainty. The regularizations depend on the structure of the matrix as well as noise level of the data. Cross-validation has been used to constrain data uncertainties in body-wave finite-frequency inversions when measurements at multiple frequencies are available to invert for a common structure. In this study, we explore an optimal Tikhonov regularization in surface-wave phase-velocity tomography based on minimization of an empirical Bayes risk function using theoretical training datasets. We exploit the structure of the sensitivity matrix in the framework of singular value decomposition (SVD) which also allows for the calculation of complete resolution matrix. We compare the optimal Tikhonov regularization in finite-frequency tomography with traditional tradeo-off analysis using surface wave dispersion measurements from global as well as regional studies.
Glaser, Adam K; Zhang, Rongxiao; Gladstone, David J; Pogue, Brian W
2014-07-21
Recent studies have proposed that light emitted by the Cherenkov effect may be used for a number of radiation therapy dosimetry applications. There is a correlation between the captured light and expected dose under certain conditions, yet discrepancies have also been observed and a complete examination of the theoretical differences has not been done. In this study, a fundamental comparison between the Cherenkov emission and absorbed dose was explored for x-ray photons, electrons, and protons using both a theoretical and Monte Carlo-based analysis. Based on the findings of where dose correlates with Cherenkov emission, it was concluded that for x-ray photons the light emission would be optimally suited for narrow beam stereotactic radiation therapy and surgery validation studies, for verification of dynamic intensity-modulated and volumetric modulated arc therapy treatment plans in water tanks, near monoenergetic sources (e.g., Co-60 and brachy therapy sources) and also for entrance and exit surface imaging dosimetry of both narrow and broad beams. For electron use, Cherenkov emission was found to be only suitable for surface dosimetry applications. Finally, for proton dosimetry, there exists a fundamental lack of Cherenkov emission at the Bragg peak, making the technique of little use, although post-irradiation detection of light emission from radioisotopes could prove to be useful.
Cosmological implications of a large complete quasar sample
Segal, I. E.; Nicoll, J. F.
1998-01-01
Objective and reproducible determinations of the probabilistic significance levels of the deviations between theoretical cosmological prediction and direct model-independent observation are made for the Large Bright Quasar Sample [Foltz, C., Chaffee, F. H., Hewett, P. C., MacAlpine, G. M., Turnshek, D. A., et al. (1987) Astron. J. 94, 1423–1460]. The Expanding Universe model as represented by the Friedman–Lemaitre cosmology with parameters qo = 0, Λ = 0 denoted as C1 and chronometric cosmology (no relevant adjustable parameters) denoted as C2 are the cosmologies considered. The mean and the dispersion of the apparent magnitudes and the slope of the apparent magnitude–redshift relation are the directly observed statistics predicted. The C1 predictions of these cosmology-independent quantities are deviant by as much as 11σ from direct observation; none of the C2 predictions deviate by >2σ. The C1 deviations may be reconciled with theory by the hypothesis of quasar “evolution,” which, however, appears incapable of being substantiated through direct observation. The excellent quantitative agreement of the C1 deviations with those predicted by C2 without adjustable parameters for the results of analysis predicated on C1 indicates that the evolution hypothesis may well be a theoretical artifact. PMID:9560182
Puviani, Luca; Rama, Sidita
2016-01-01
Despite growing scientific interest in the placebo effect and increasing understanding of neurobiological mechanisms, theoretical modeling of the placebo response remains poorly developed. The most extensively accepted theories are expectation and conditioning, involving both conscious and unconscious information processing. However, it is not completely understood how these mechanisms can shape the placebo response. We focus here on neural processes which can account for key properties of the response to substance intake. It is shown that placebo response can be conceptualized as a reaction of a distributed neural system within the central nervous system. Such a reaction represents an integrated component of the response to open substance administration (or to substance intake) and is updated through “unconditioned stimulus (UCS) revaluation learning”. The analysis leads to a theorem, which proves the existence of two distinct quantities coded within the brain, these are the expected or prediction outcome and the reactive response. We show that the reactive response is updated automatically by implicit revaluation learning, while the expected outcome can also be modulated through conscious information processing. Conceptualizing the response to substance intake in terms of UCS revaluation learning leads to the theoretical formulation of a potential neuropharmacological treatment for increasing unlimitedly the effectiveness of a given drug. PMID:27436417
Puviani, Luca; Rama, Sidita
2016-07-20
Despite growing scientific interest in the placebo effect and increasing understanding of neurobiological mechanisms, theoretical modeling of the placebo response remains poorly developed. The most extensively accepted theories are expectation and conditioning, involving both conscious and unconscious information processing. However, it is not completely understood how these mechanisms can shape the placebo response. We focus here on neural processes which can account for key properties of the response to substance intake. It is shown that placebo response can be conceptualized as a reaction of a distributed neural system within the central nervous system. Such a reaction represents an integrated component of the response to open substance administration (or to substance intake) and is updated through "unconditioned stimulus (UCS) revaluation learning". The analysis leads to a theorem, which proves the existence of two distinct quantities coded within the brain, these are the expected or prediction outcome and the reactive response. We show that the reactive response is updated automatically by implicit revaluation learning, while the expected outcome can also be modulated through conscious information processing. Conceptualizing the response to substance intake in terms of UCS revaluation learning leads to the theoretical formulation of a potential neuropharmacological treatment for increasing unlimitedly the effectiveness of a given drug.
NASA Astrophysics Data System (ADS)
Cotti, Gina; Linnartz, Harold; Meerts, W. Leo; van der Avoird, Ad; Olthof, Edgar H. T.
1996-03-01
In this paper we present Stark measurements on the G:K=-1 vibration-rotation-tunneling (VRT) transition, band origin 747.2 GHz, of the ammonia dimer. The observed splitting pattern and selection rules can be explained by considering the G36 and G144 symmetries of the inversion states involved, and almost complete mixing of these states by the applied electric field. The absolute values of the electric dipole moments of the ground and excited state are determined to be 0.763(15) and 0.365(10) D, respectively. From the theoretical analysis and the observed selection rules it is possible to establish that the dipole moments of the two interchange states must have opposite sign. The theoretical calculations are in good agreement with the experimental results: The calculated dipole moments are -0.74 D for the lower and +0.35 D for the higher state. Our results, in combination with the earlier dipole measurements on the G:K=0 ground state and the G:K=1 transition with band origin 486.8 GHz, confirm that the ammonia dimer is highly nonrigid. Its relatively small and strongly K-dependent dipole moment, which changes sign upon far-infrared excitation, originates from the difference in dynamical behavior of ortho and para NH3.
NASA Astrophysics Data System (ADS)
Gomez-Diaz, Juan Sebastian
This PhD. dissertation presents a multidisciplinary work, which involves the development of different novel formulations applied to the accurate and efficient analysis of a wide variety of new structures, devices, and phenomena at themicrowave frequency region. The objectives of the present work can be divided into three main research lines: (1) The first research line is devoted to the Green's function analysis of multilayered enclosures with convex arbitrarily-shaped cross section. For this purpose, three accurate spatial-domain formulations are developed at the Green's functions level. These techniques are then efficiently incorporated into a mixed-potential integral equation framework, which allows the fast and accurate analysis of multilayered printed circuits in shielded enclosures. The study of multilayered shielded circuits has lead to the development of the novel hybridwaveguide-microstrip filter technology, which is light, compact, low-loss and presents important advantages for the space industry. (2) The second research line is related to the impulse-regime study ofmetamaterial-based composite right/left-handed (CRLH) structures and the subsequent theoretical and practical demonstration of several novel optically-inspired phenomena and applications at microwaves, in both, the guided and the radiative region. This study allows the development of new devices for ultra wide band and high data-rate communications systems. Besides, this research line also deals with the simple and accurate characterization of CRLH leaky-wave antennas using transmission line theory. (3) The third and last research line presents a novel CRLH parallel-plate waveguide leaky-wave antenna structure, and a rigorous iterative modal-based technique for its fast and complete characterization, including a systematic calculation of the antenna physical dimensions. It is important to point out that all the theoretical developments and novel structures presented in thiswork have been numerically confirmed, by the use of both, home-made software and commercial full-wave simulations, and experimentally verified, by the use of measurements from fabricated prototypes.
Advance care planning among Colombian, Mexican, and Puerto Rican women with a cancer diagnosis.
Carrion, Iraida V; Nedjat-Haiem, Frances R; Martinez-Tyson, Dinorah; Castañeda, Heide
2013-05-01
Limited knowledge exists pertaining to advance care planning (ACP) among Colombian, Mexican, and Puerto Rican women with a cancer diagnosis living in Central Florida, in the USA. The purpose of the study is to identify factors that facilitated the completion of ACP and decisions making patterns among the three groups of Latinas. The research method used was an exploratory qualitative in-depth open-ended semi-structured interview with a grounded theoretical approach and thematic analysis. The interviews were conducted in Spanish with a purposeful sample of 45 Latinas (15 in each group) diagnosed with cancer. A total of ten women (22 %) in the study documented at least one form of ACP. Thirty-five women identified obstacles to accessing information regarding ACP, relating this to insurance and financial factors. Among the Colombian women, one completed a living will, health care surrogate, and power of attorney (all forms of ACP), and three just a living will. Two Puerto Rican women completed all, two a living will, and one both a living will and an enduring power of attorney. Only one Mexican woman completed a living will. This study identifies a knowledge gap regarding ACP among Latina women with cancer diagnosis living in Central Florida, in the USA. Differences between the three groups exist as a result of migration/immigration history, family support, education, English language proficiency, income, knowledge gaps, and information ascertained by medical and health professionals. These differences contribute to their readiness, receptiveness, and willingness to engage in documenting a living will, a health care surrogate, and an enduring power of attorney for health decisions.
A complete VLBI delay model for deforming radio telescopes: the Effelsberg case
NASA Astrophysics Data System (ADS)
Artz, T.; Springer, A.; Nothnagel, A.
2014-12-01
Deformations of radio telescopes used in geodetic and astrometric very long baseline interferometry (VLBI) observations belong to the class of systematic error sources which require correction in data analysis. In this paper we present a model for all path length variations in the geometrical optics of radio telescopes which are due to gravitational deformation. The Effelsberg 100 m radio telescope of the Max Planck Institute for Radio Astronomy, Bonn, Germany, has been surveyed by various terrestrial methods. Thus, all necessary information that is needed to model the path length variations is available. Additionally, a ray tracing program has been developed which uses as input the parameters of the measured deformations to produce an independent check of the theoretical model. In this program as well as in the theoretical model, the illumination function plays an important role because it serves as the weighting function for the individual path lengths depending on the distance from the optical axis. For the Effelsberg telescope, the biggest contribution to the total path length variations is the bending of the main beam located along the elevation axis which partly carries the weight of the paraboloid at its vertex. The difference in total path length is almost 100 mm when comparing observations at 90 and at 0 elevation angle. The impact of the path length corrections is validated in a global VLBI analysis. The application of the correction model leads to a change in the vertical position of mm. This is more than the maximum path length, but the effect can be explained by the shape of the correction function.
NASA Astrophysics Data System (ADS)
Sherin Percy Prema Leela, J.; Hemamalini, R.; Muthu, S.; Al-Saadi, Abdulaziz A.
2015-07-01
Capsicum a hill grown vegetable is also known as red pepper or chili pepper. Capsaicin(8-Methyl-N-vanillyl-6-nonenamide) is the active component in chili peppers, which is currently used in the treatment of osteoarthritis, psoriasis and cancer. Fourier transform infrared (FT-IR) spectrum of Capsaicin in the solid phase were recorded in the region 4000-400 cm-1 and analyzed. The vibrational frequencies of the title compound were obtained theoretically by DFT/B3LYP calculations employing the standard 6-311++G(d,p) basis set and were compared with Fourier transform infrared spectrum. Complete vibrational assignment analysis and correlation of the fundamental modes for the title compound were carried out. The vibrational harmonic frequencies were scaled using scale factor, yielding a good agreement between the experimentally recorded and the theoretically calculated values. Stability of the molecule arising from hyper conjugative interactions, charge delocalization and intra molecular hydrogen bond-like weak interaction has been analyzed using Natural bond orbital (NBO) analysis by using B3LYP/6-311++G(d,p) method. The results show that electron density (ED) in the σ∗ and π∗ antibonding orbitals and second-order delocalization energies E (2) confirm the occurrence of intra molecular charge transfer (ICT) within the molecule. The dipole moment (μ), polarizability (α) and the hyperpolarizability (β) values of the molecule has been computed. Thermodynamic properties (heat capacity, entropy and enthalpy) of the title compound at different temperatures were calculated.
The Development of an Empirical Model of Mental Health Stigma in Adolescents.
Silke, Charlotte; Swords, Lorraine; Heary, Caroline
2016-08-30
Research on mental health stigma in adolescents is hampered by a lack of empirical investigation into the theoretical conceptualisation of stigma, as well as by the lack of validated stigma measures. This research aims to develop a model of public stigma toward depression in adolescents and to use this model to empirically examine whether stigma is composed of three separate dimensions (Stereotypes, Prejudice and Discrimination), as is theoretically proposed. Adolescents completed self-report measures assessing their stigmatising responses toward a fictional peer with depression. An exploratory factor analysis (EFA; N=332) was carried out on 58-items, which proposed to measure aspects of stigma. A confirmatory factor analysis (CFA; N=236) was then carried out to evaluate the validity of the observed stigma model. Finally, higher-order CFAs were conducted in order to assess whether the observed model supported the tripartite conceptualisation of stigma. The EFA returned a seven-factor model of stigma. These factors were designated as Dangerousness, Warmth & Competency, Responsibility, Negative Attributes, Prejudice, Classroom Discrimination and Friendship Discrimination. The CFA supported the goodness-of-fit of this seven-factor model. The higher-order CFAs indicated that these seven factors represented the latent constructs of, Stereotypes, Prejudice and Discrimination, which in turn represented Stigma. Overall, results support the tripartite conceptualisation of stigma and suggest that measurements of mental health stigma in adolescents should include assessments of all three dimensions. These results also highlight the importance of establishing valid and reliable measures for assessing stigma in adolescents. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.
The operational context of care sport connectors in the Netherlands.
Leenaars, K E F; van der Velden-Bollemaat, E C; Smit, E; Wagemakers, A; Molleman, G R M; Koelen, M A
2017-02-22
To stimulate physical activity (PA) and guide primary care patients towards local sport facilities, Care Sport Connectors (CSCs), to whom a broker role has been ascribed, were introduced in 2012 in the Netherlands. The aim of this study is to describe CSCs' operational context. A theoretical framework was developed and used as the starting point for this study. Group interviews were held with policymakers in nine participating municipalities, and, when applicable, the CSC's manager was also present. Prior to the interviews, a first outline of the operational context was mapped, based on the analysis of policy documents and a questionnaire completed by the policymakers. A deductive content analysis, based on the theoretical framework, was used to analyse the interviews. Differences were found in CSCs' operational context in the different municipalities, especially the extent to which municipalities adopted an integral approach. An integral approach consists of an integral policy in combination with an imbedding of this policy in partnerships at management level. This integral approach is reflected in the activities of other municipal operations, for example the implementation of health and PA programs by different organisations. Given the CSC mandate, we think that this integral approach may be supportive of the CSCs' work, because it is reflected in other operations of the municipalities and thus creates conditions for the CSCs' work. Further study is required to ascertain whether this integral approach is actually supporting CSCs in their work to connect the primary care and the PA sector. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
NASA Technical Reports Server (NTRS)
Wolf, S. W. D.
1977-01-01
Work has continued with the low speed self streamlining wind tunnel (SSWT) using the NACA 0012-64 airfoil in an effort to explain the discrepancies between the NASA Langley low turbulence pressure tunnel (LTPT) and SSWT results obtained with the airfoil stalled. Conventional wind tunnel corrections were applied to straight wall SSWT airfoil data, to illustrate the inadequacy of standard correction techniques in circumstances of high blockage. Also one SSWT test was re-run at different air speeds to investigate the effects of such changes on airfoil data and wall contours. Mechanical design analyses for the transonic self streamlining wind tunnel (TSWT) were completed by the application of theoretical airfoil flow field data to the elastic beam and streamline analysis. The control system for the transonic facility is outlined.
[Review of food policy approaches: from food security to food sovereignty (2000-2013)].
López-Giraldo, Luis Alirio; Franco-Giraldo, Álvaro
2015-07-01
Food policies have attracted special interest due to the global food crisis in 2008 and promotion of the Millennium Development Goals, leading to approaches by different fields. This thematic review aims to describe the main theoretical and methodological approaches to food security and food sovereignty policies. A search was performed in databases of scientific journals from 2000 to 2013. 320 complete articles were selected from a total of 2,699. After reading the articles to apply the inclusion criteria, 55 items were maintained for analysis. In conclusion, with the predominance of food security as a guiding policy, food sovereignty has emerged as a critical response to be included in designing and researching food policies. Food policies are essential for achieving public health goals. Public health should thus take a leading role in linking and orienting such policies.
A mass-energy preserving Galerkin FEM for the coupled nonlinear fractional Schrödinger equations
NASA Astrophysics Data System (ADS)
Zhang, Guoyu; Huang, Chengming; Li, Meng
2018-04-01
We consider the numerical simulation of the coupled nonlinear space fractional Schrödinger equations. Based on the Galerkin finite element method in space and the Crank-Nicolson (CN) difference method in time, a fully discrete scheme is constructed. Firstly, we focus on a rigorous analysis of conservation laws for the discrete system. The definitions of discrete mass and energy here correspond with the original ones in physics. Then, we prove that the fully discrete system is uniquely solvable. Moreover, we consider the unconditionally convergent properties (that is to say, we complete the error estimates without any mesh ratio restriction). We derive L2-norm error estimates for the nonlinear equations and L^{∞}-norm error estimates for the linear equations. Finally, some numerical experiments are included showing results in agreement with the theoretical predictions.
NASA Astrophysics Data System (ADS)
Kumar, Amarendra; Narayan, Vijay; Prasad, Onkar; Sinha, Leena
2012-08-01
Quantum chemical calculations of energies, dipole moment, polarizability, hyperpolarizability and vibrational wavenumbers of Azelaic acid (AZA) were carried out by using ab initio HF and B3LYP methods with 6-311++G(d,p) basis set. Hydrogen-bonded dimer of AZA, optimized by counterpoise correction, has also been studied by HF and B3LYP at the 6-311++G(d,p) level and the effects of molecular association through Osbnd H⋯O hydrogen bonding have been discussed. A complete vibrational analysis of AZA has been performed and assignments are made on the basis of potential energy distribution. The comparisons and assignments of the vibrational frequencies indicate that the experimental spectra also correspond acceptably with those of theoretically simulated spectra except the hydrogen-bonded coupled infrared vibrations.
Dark matter from a classically scale-invariant S U (3 )X
NASA Astrophysics Data System (ADS)
Karam, Alexandros; Tamvakis, Kyriakos
2016-09-01
In this work we study a classically scale-invariant extension of the Standard Model in which the dark matter and electroweak scales are generated through the Coleman-Weinberg mechanism. The extra S U (3 )X gauge factor gets completely broken by the vacuum expectation values of two scalar triplets. Out of the eight resulting massive vector bosons the three lightest are stable due to an intrinsic Z2×Z2' discrete symmetry and can constitute dark matter candidates. We analyze the phenomenological viability of the predicted multi-Higgs sector imposing theoretical and experimental constraints. We perform a comprehensive analysis of the dark matter predictions of the model solving numerically the set of coupled Boltzmann equations involving all relevant dark matter processes and explore the direct detection prospects of the dark matter candidates.