Theoretical numerical analysis
Wendroff, Burton
1966-01-01
Theoretical Numerical Analysis focuses on the presentation of numerical analysis as a legitimate branch of mathematics. The publication first elaborates on interpolation and quadrature and approximation. Discussions focus on the degree of approximation by polynomials, Chebyshev approximation, orthogonal polynomials and Gaussian quadrature, approximation by interpolation, nonanalytic interpolation and associated quadrature, and Hermite interpolation. The text then ponders on ordinary differential equations and solutions of equations. Topics include iterative methods for nonlinear systems, matri
Theoretically extensible quantum digital signature with starlike cluster states
Yang, Yu-Guang; Liu, Zhi-Chao; Li, Jian; Chen, Xiu-Bo; Zuo, Hui-Juan; Zhou, Yi-Hua; Shi, Wei-Min
2017-01-01
Chen et al. (Phys Rev A 73:012303, 2006) constructed this "starlike cluster" state, which involves one qubit located at the center and n neighboring two-qubit arms. This genuine entangled state has been used for the construction of 2D and 3D cluster states, topological one-way computation, and dynamical quantum secret sharing. In this paper, we investigate the usefulness of this starlike cluster state and propose a theoretically extensible quantum digital signature scheme. The proposed scheme can be theoretically generalized to more than three participants. Moreover, it retains the merits of no requirements such as authenticated quantum channels and long-term quantum memory. We also give a security proof for the proposed scheme against repudiation and forgery.
Diesel, Vivien; Miná Dias, Marcelo
2016-01-01
Purpose: To analyze the Brazilian experience in designing and implementing a recent extension policy reform based on agroecology, and reflect on its wider theoretical implications for extension reform literature. Design/methodology/approach: Using a critical public analysis we characterize the evolution of Brazilian federal extension policy…
A ring theoretic approach to radicals of extensions
Williams, Jessica Lynn
The Jacobson radical of a ring was first formally studied in 1945 by Nathan Jacobson and is an important object in modern abstract algebra. The analogous notion of the Jacobson radical for a module is referred to as the radical of a module. The radical of a module is the intersection of all its maximal submodules. In general, the radical of a module is simpler than the module itself and contains important information about the module. The study of the radical of a module often appears as an incidental to other investigations. This thesis represents work towards understanding the radical of a module extension. Given a ring R and R-modules A,B,X such that X is an extension of B by A as in the short exact sequence 0 → A → X → B → 0; we seek to determine properties of the radical of X, denoted radX. These properties are dependent on the ring R and properties of the modules A and B. In this thesis we examine several different types of extensions and discuss a phenomenon in which a non-zero radical implies a split sequence. We work in the context of rings and their ideals. Extensions of abelian groups provide motivation for the results we prove about injectivity of radicals of extensions involving divisible modules and torsion modules. We are able to prove such properties of the radical for extensions of modules over principal ideal domains and Dedekind domains. Expanding upon these cases, we explore a more general construction of an extension and use it to explain our motivating abelian group results. We use the theorems proven about this construction to remark on possible generalizations to other types of rings and modules. We conclude with plans to generalize our statements by translating into terms of infinite matrices and h-local rings.
Extensive analysis of hydrogen costs
Energy Technology Data Exchange (ETDEWEB)
Guinea, D.M.; Martin, D.; Garcia-Alegre, M.C.; Guinea, D. [Consejo Superior de Investigaciones Cientificas, Arganda, Madrid (Spain). Inst. de Automatica Industrial; Agila, W.E. [Acciona Infraestructuras, Alcobendas, Madrid (Spain). Dept. I+D+i
2010-07-01
Cost is a key issue in the spreading of any technology. In this work, the cost of hydrogen is analyzed and determined, for hydrogen obtained by electrolysis. Different contributing partial costs are taken into account to calculate the hydrogen final cost, such as energy and electrolyzers taxes. Energy cost data is taken from official URLs, while electrolyzer costs are obtained from commercial companies. The analysis is accomplished under different hypothesis, and for different countries: Germany, France, Austria, Switzerland, Spain and the Canadian region of Ontario. Finally, the obtained costs are compared to those of the most used fossil fuels, both in the automotive industry (gasoline and diesel) and in the residential sector (butane, coal, town gas and wood), and the possibilities of hydrogen competing against fuels are discussed. According to this work, in the automotive industry, even neglecting subsidies, hydrogen can compete with fossil fuels. Hydrogen can also compete with gaseous domestic fuels. Electrolyzer prices were found to have the highest influence on hydrogen prices. (orig.)
A Theoretical Extension of the Technology Acceptance Model: Four Longitudinal Field Studies
Viswanath Venkatesh; Fred D. Davis
2000-01-01
The present research develops and tests a theoretical extension of the Technology Acceptance Model (TAM) that explains perceived usefulness and usage intentions in terms of social influence and cognitive instrumental processes. The extended model, referred to as TAM2, was tested using longitudinal data collected regarding four different systems at four organizations (N = 156), two involving voluntary usage and two involving mandatory usage. Model constructs were measured at three points in ti...
Dental Photothermal Radiometry: Theoretical Analysis.
Matvienko, Anna; Jeon, Raymond; Mandelis, Andreas; Abrams, Stephen
2007-03-01
Dental enamel demineralization in its early stages is very difficult to detect with conventional x-rays or visual examination. High-resolution techniques, such as scanning electron microscopy, usually require destruction of the tooth. Photothermal Radiomety (PTR) was recently applied as a safe, non-destructive, and highly sensitive tool for the detection of early dental demineralization, artificially created on the enamel surface. The experiments showed very high sensitivity of the measured signal to incipient changes in the surface structure, emphasizing the clinical capabilities of the method. In order to analyze the biothermophotonic phenomena in a tooth sample during the photothermal excitation, a theoretical model featuring coupled diffuse-photon-density-wave and thermal-wave fields was developed. Numerical simulations identified the effects on the PTR signal of changes in optical and thermal properties of enamel and dentin as a result of demineralization. The model predictions and experimental results will be compared and discussed.
Analysis of Extension Categorical Data Mining Process for the Extension Interior Designing
Institute of Scientific and Technical Information of China (English)
Hui Ma; Guangtian Zou
2016-01-01
On the basis of extension architectonics, this paper researches the process of extension categorical data mining for extension interior design. In accordance with the theory of extension data mining, the extension categorical data mining for the extension interior design can be divided into data preparation, the operation of mining and knowledge application. The paper expatiates the main content and cohesive relations of each link, and emphatically discusses extension acquisition, analysis extension, categorical mining extension, knowledge application extension and other several core nodes that are related with data. Through the knowledge fusion of extension architectonics and data mining, the paper discusses the process of knowledge requirements with multiple classification under different mining targets. The purpose of this paper is to explore a whole categorical data mining process of interior design from extension design data to the design of knowledge discovery and extension application.
Theoretical analysis of sheet metal formability
Zhu, Xinhai
Sheet metal forming processes are among the most important metal-working operations. These processes account for a sizable proportion of manufactured goods made in industrialized countries each year. Furthermore, to reduce the cost and increase the performance of manufactured products, in addition to the environmental concern, more and more light weight and high strength materials have been used as a substitute to the conventional steel. These materials usually have limited formability, thus, a thorough understanding of the deformation processes and the factors limiting the forming of sound parts is important, not only from a scientific or engineering viewpoint, but also from an economic point of view. An extensive review of previous studies pertaining to theoretical analyses of Forming Limit Diagrams (FLDs) is contained in Chapter I. A numerical model to analyze the neck evolution process is outlined in Chapter II. With the use of strain gradient theory, the effect of initial defect profile on the necking process is analyzed. In the third chapter, the method proposed by Storen and Rice is adopted to analyze the initiation of localized neck and predict the corresponding FLDs. In view of the fact that the width of the localized neck is narrow, the deformation inside the neck region is constrained by the material in the neighboring homogeneous region. The relative rotation effect may then be assumed to be small and is thus neglected. In Chapter IV, Hill's 1948 yield criterion and strain gradient theory are employed to obtain FLDs, for planar anisotropic sheet materials by using bifurcation analysis. The effects of the strain gradient coefficient c and the material anisotropic parameters R's on the orientation of the neck and FLDs are analyzed in a systematic manner and compared with experiments. In Chapter V, Hill's 79 non-quadratic yield criterion with a deformation theory of plasticity is used along with bifurcation analyses to derive a general analytical
Theoretical numerical analysis a functional analysis framework
Atkinson, Kendall
2005-01-01
This textbook prepares graduate students for research in numerical analysis/computational mathematics by giving to them a mathematical framework embedded in functional analysis and focused on numerical analysis. This helps the student to move rapidly into a research program. The text covers basic results of functional analysis, approximation theory, Fourier analysis and wavelets, iteration methods for nonlinear equations, finite difference methods, Sobolev spaces and weak formulations of boundary value problems, finite element methods, elliptic variational inequalities and their numerical solu
Energy Technology Data Exchange (ETDEWEB)
Lind, M. [Oersted - DTU, Kgs. Lyngby (Denmark)
2005-10-01
Multilevel Flow Modeling (MFM) has proven to be an effective modeling tool for reasoning about plant failure and control strategies and is currently exploited for operator support in diagnosis and on-line alarm analysis. Previous MFM research was focussed on representing goals and functions of process plants which generate, transform and distribute mass and energy. However, only a limited consideration has been given to the problems of modeling the control systems. Control functions are indispensable for operating any industrial plant. But modeling of control system functions has proven to be a more challenging problem than modeling functions of energy and mass processes. The problems were discussed by Lind and tentative solutions has been proposed but have not been investigated in depth until recently, partly due to the lack of an appropriate theoretical foundation. The purposes of the present report are to show that such a theoretical foundation for modeling goals and functions of control systems can be built from concepts and theories of action developed by Von Wright and to show how the theoretical foundation can be used to extend MFM with concepts for modeling control systems. The theoretical foundations has been presented in detail elsewhere by the present author without the particular focus on modeling control actions and MFM adopted here. (au)
A Theoretical Analysis of Ball Spinning
Institute of Scientific and Technical Information of China (English)
无
2002-01-01
As a special method of manufacturing thin wall tubes, the ball spinning process has been used for nearly 30 years because of its less investment of equipment, higher precision, and more perfect properties of products. However, the application is limited since the process parameters are determined based on empirical data and laboratory experiments for lack of a whole theoretical analysis. In this paper, some basic parameters such as the force and power parameters have been studied based on an analysis of geometry and mechanics of the process. The calculation of forming forces and the selection of the working angle are carried out. At the end, a perfect comparison between the results of the experiments and the theoretical analysis is made.
Theoretical discussions on the geometrical phase analysis
Energy Technology Data Exchange (ETDEWEB)
Rouviere, J.L. [CEA-Grenoble, Departement de Recherche Fondamentale sur la Matiere Condensee, SP2M, 17 rue des Martyrs, 38054 Grenoble Cedex 9 (France)]. E-mail: rouvierej@cea.fr; Sarigiannidou, E. [CEA-Grenoble, Departement de Recherche Fondamentale sur la Matiere Condensee, SP2M, 17 rue des Martyrs, 38054 Grenoble Cedex 9 (France)
2005-12-15
The Geometrical phase analysis, which is a very efficient method to measure deformation from High resolution transmission electron microscopy images, is studied from a theoretical point of view. We point out that the basic property of this method is its ability to measure local reciprocal lattice parameters with a high level of accuracy. We attempt to provide some insights into (a) different formula used in the geometrical phase analysis such as the well-known relation between phase and displacement: P{sub g}(r)=-2{pi}g.u(r), (b) the two different definitions of strain, each of which corresponding to a different lattice reference and (c) the meaning of a continuous displacement in a dot-like high resolution image. The case of one-dimensional analysis is also presented. Finally, we show that the method is able to give the position of the dot that is nearest to a given pixel in the image.
Intermittency in Switching Power Converters: Theoretical Analysis
Institute of Scientific and Technical Information of China (English)
ZHOU Yu-fei; CHEN Jun-ning; TSE Chi K.; QIU Shui-sheng; KE Dao-ming; SHI Long-xing; SUN Wei-feng
2006-01-01
In view of reasonable explanation of intermittent subharmonics and chaos that can be gained from coupling filter between circuits,this paper discusses a method that maps time bifurcation with parameter bifurcation.Based on this mapping method,the general analysis method of characteristic multiplier,which is originally aimed at parameter bifurcation,can be used for the study of intermittency,i.e.,time bifurcation.In this paper,all researches coming from characteristic multipliers,parameter-bifurcation diagrams,and the largest Lyapunov exponent indicate the same results as those produced by simulation and experiment.Thus,it is proved theoretically that the intermittency in switching power converter can be explained in terms of coupling of spurious interference.
Theoretical and methodological approaches in discourse analysis.
Stevenson, Chris
2004-10-01
Discourse analysis (DA) embodies two main approaches: Foucauldian DA and radical social constructionist DA. Both are underpinned by social constructionism to a lesser or greater extent. Social constructionism has contested areas in relation to power, embodiment, and materialism, although Foucauldian DA does focus on the issue of power. Embodiment and materialism may be especially relevant for researchers of nursing where the physical body is prominent. However, the contested nature of social constructionism allows a fusion of theoretical and methodological approaches tailored to a specific research interest. In this paper, Chris Stevenson suggests a frame- work for working out and declaring the DA approach to be taken in relation to a research area, as well as to aid anticipating methodological critique. Method, validity, reliability and scholarship are discussed from within a discourse analytic frame of reference.
Analysis of a theoretically optimized transonic airfoil
Lores, M. E.; Burdges, K. P.; Shrewsbury, G. D.
1978-01-01
Numerical optimization was used in conjunction with an inviscid, full potential equation, transonic flow analysis computer code to design an upper surface contour for a conventional airfoil to improve its supercritical performance. The modified airfoil was tested in a compressible flow wind tunnel. The modified airfoil's performance was evaluated by comparison with test data for the baseline airfoil and for an airfoil developed by optimization of leading edge of the baseline airfoil. While the leading edge modification performed as expected, the upper surface re-design did not produce all of the expected performance improvements. Theoretical solutions computed using a full potential, transonic airfoil code corrected for viscosity were compared to experimental data for the baseline airfoil and the upper surface modification. These correlations showed that the theory predicted the aerodynamics of the baseline airfoil fairly well, but failed to accurately compute drag characteristics for the upper surface modification.
ANALYSIS OF THE PROTECTED EXTENSIBLE AUTHENTICATION PROTOCOL
Directory of Open Access Journals (Sweden)
Amit Rana
2012-09-01
Full Text Available The Internet Engineering Task Force (IETF has proposednew protocols for highly secured wireless networking. Thepurpose of this paper is to implement one such proposedsecurity protocol - PEAP (Protected ExtensibleAuthentication Protocol [1]. PEAP was jointly developedby Microsoft, Cisco and RSA security. The protocolimplementation is done on the server end of a Client/Servernetwork model on a RADIUS server (RemoteAuthentication Dial-in User Service. The proposedprotocol - PEAP provides for Client identity protection andkey generation thus preventing unauthorized user accessand protecting or encrypting the data against maliciousactivities.
EXTENSION TO THEORY OF TIME SERIES ANALYSIS
vector-valued processes; analysis of processes with vector arguments; and the influence of finite sample size on the covariance matrices of the least square and Markov estimates in regression analysis. (Author)
Extensions in model-based system analysis
Graham, Matthew R.
2007-01-01
Model-based system analysis techniques provide a means for determining desired system performance prior to actual implementation. In addition to specifying desired performance, model-based analysis techniques require mathematical descriptions that characterize relevant behavior of the system. The developments of this dissertation give ex. tended formulations for control- relevant model estimation as well as model-based analysis conditions for performance requirements specified as frequency do...
Heymann, F. V.
1998-01-01
Wageningen University's extension science program shifted from a positivist to a constructivist foundation. Participatory methodologies and interactive policies are being developed, and the program's name has been changed to Communication and Innovation Studies. (SK)
Convergence of the discrete dipole approximation. I. Theoretical analysis
Yurkin, Maxim A; Hoekstra, Alfons G
2006-01-01
We performed a rigorous theoretical convergence analysis of the discrete dipole approximation (DDA). We prove that errors in any measured quantity are bounded by a sum of a linear and quadratic term in the size of a dipole d, when the latter is in the range of DDA applicability. Moreover, the linear term is significantly smaller for cubically than for non-cubically shaped scatterers. Therefore, for small d errors for cubically shaped particles are much smaller than for non-cubically shaped. The relative importance of the linear term decreases with increasing size, hence convergence of DDA for large enough scatterers is quadratic in the common range of d. Extensive numerical simulations were carried out for a wide range of d. Finally we discuss a number of new developments in DDA and their consequences for convergence.
Strategy Effectiveness of Game-Theoretical Solution Concepts in Extensive-Form General-Sum Games
DEFF Research Database (Denmark)
Cermak, Jiri; Bosansky, Branislav; Gatti, Nicola
Academic communities have adopted different conventions for ordering authors on academic publications. Are these choices inconsequential, or can they significantly impact individual authors, or even communities at large? We consider a game theoretic model to study allocation of credit to authors;...
SET-VALUED EXTENSION OF OPERATORS VIA STEINER SELECTIONS (Ⅰ)-THEORETICAL RESULTS
Institute of Scientific and Technical Information of China (English)
Ter(a)n,Pedro; L(o)pez-D(I)an,Miguel
2002-01-01
A way to extend operators in spaces of continuous functions to spaces ofcontinuous set-valued functions is proposed. This extension is developed through the Steinerselections of the set-valued functions. Their properties and characteristics of theconvergence of sequences of operators of this class are studied. In Part Ⅱ of this seriessome applications to approximation theory will be shown.
A Meta-Analysis of Extensive Reading Research
Nakanishi, Takayuki
2015-01-01
The purposes of this study were to investigate the overall effectiveness of extensive reading, whether learners' age impacts learning, and whether the length of time second language learners engage in extensive reading influences test scores. The author conducted a meta-analysis to answer research questions and to identify future research…
Mapping Extension's Networks: Using Social Network Analysis to Explore Extension's Outreach
Bartholomay, Tom; Chazdon, Scott; Marczak, Mary S.; Walker, Kathrin C.
2011-01-01
The University of Minnesota Extension conducted a social network analysis (SNA) to examine its outreach to organizations external to the University of Minnesota. The study found that its outreach network was both broad in its reach and strong in its connections. The study found that SNA offers a unique method for describing and measuring Extension…
Theoretical parametric study of the relative advantages of winglets and wing-tip extensions
Heyson, H. H.; Riebe, G. D.; Fulton, C. L.
1977-01-01
It was found that for identical increases in bending moment, a winglet provides a greater gain in induced efficiency than a tip extension. Winglet toe-in angle allows design trades between efficiency and root moment. A winglet showed the greatest benefit when the wing loads were heavy near the tip. Washout diminished the benefit of either tip modification, and the gain in induced efficiency became a function of lift coefficient; heavy wing loadings obtained the greatest benefit from a winglet, and low speed performance was enhanced even more than cruise performance. Both induced efficiency and bending moment increased with winglet length and outward cant. The benefit of a winglet relative to a tip extension was greatest for a nearly vertical winglet. Root bending moment was proportional to the minimum weight of bending material required in the wing; it is a valid index of the impact of tip modifications on a new wing design.
Directory of Open Access Journals (Sweden)
Dagiuklas Tasos
2011-01-01
Full Text Available This paper presents a Wireless Information-Theoretic Security (WITS scheme, which has been recently introduced as a robust physical layer-based security solution, especially for infrastructureless networks. An autonomic network of moving users was implemented via 802.11n nodes of an ad hoc network for an outdoor topology with obstacles. Obstructed-Line-of-Sight (OLOS and Non-Line-of-Sight (NLOS propagation scenarios were examined. Low-speed user movement was considered, so that Doppler spread could be discarded. A transmitter and a legitimate receiver exchanged information in the presence of a moving eavesdropper. Average Signal-to-Noise Ratio (SNR values were acquired for both the main and the wiretap channel, and the Probability of Nonzero Secrecy Capacity was calculated based on theoretical formula. Experimental results validate theoretical findings stressing the importance of user location and mobility schemes on the robustness of Wireless Information-Theoretic Security and call for further theoretical analysis.
Call, Matthew L; Nyberg, Anthony J; Thatcher, Sherry M B
2015-05-01
Stars--employees with disproportionately high and prolonged (a) performance, (b) visibility, and (c) relevant social capital--have garnered attention in economics, sociology, and management. However, star research is often isolated within these research disciplines. Thus, 3 distinct star research streams are evolving, each disconnected from the others and each bringing siloed theoretical perspectives, terms, and assumptions. A conceptual review of these perspectives reveals a focus on the expost effects that stars exert in organizations with little explanation of who a star is and how one becomes a star. To synthesize the stars literature across these 3 disciplines, we apply psychological theories, specifically motivation theories, to create an integrative framework for stars research. Thus, we present a unified stars definition and extend theory on the making, managing, and mobility of stars. We extend research about how and why employees may be motivated to become stars, how best to manage stars and their relationships with colleagues, and how to motivate star retention. We then outline directions for future research. (c) 2015 APA, all rights reserved.
A Temporal Extension to Traditional Empirical Orthogonal Function Analysis
DEFF Research Database (Denmark)
Nielsen, Allan Aasbjerg; Hilger, Klaus Baggesen; Andersen, Ole Baltazar
2002-01-01
This paper describes the application of temporal maximum autocorrelation factor analysis to global monthly mean values of 1996-1997 sea surface temperature (SST) and sea surface height (SSH) data. This type of analysis can be considered as an extension of traditional empirical orthogonal function...
Disability and Humans Rights: A Theoretical Analysis
Directory of Open Access Journals (Sweden)
PATRICIA CUENCA GÓMEZ
2015-06-01
Full Text Available Since Enlightenment, theories of justice and, in particular, theories of human rights have been based on principles which are excludable for people with disabilities. The exclusion has not been resolved by contemporary theories of justice. A profound review of some basic assumptions is required to get a full and sound theory of human rights including people with disabilities in equal terms. The inclusion of people with disabilities is an urgent theoretical challenge which must be face in order to perform a sound reform of rules in legal practice.
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.
1979-01-01
The objectives, conclusions, and approaches for accomplishing 19 specific design and analysis activities related to the installation of the power extension package (PEP) into the Orbiter cargo bay are described as well as those related to its deployment, extension, and retraction. The proposed cable handling system designed to transmit power from PEP to the Orbiter by way of the shuttle remote manipulator system is described and a preliminary specification for the gimbal assembly, solar array drive is included.
Landscape analysis: Theoretical considerations and practical needs
Godfrey, A.E.; Cleaves, E.T.
1991-01-01
Numerous systems of land classification have been proposed. Most have led directly to or have been driven by an author's philosophy of earth-forming processes. However, the practical need of classifying land for planning and management purposes requires that a system lead to predictions of the results of management activities. We propose a landscape classification system composed of 11 units, from realm (a continental mass) to feature (a splash impression). The classification concerns physical aspects rather than economic or social factors; and aims to merge land inventory with dynamic processes. Landscape units are organized using a hierarchical system so that information may be assembled and communicated at different levels of scale and abstraction. Our classification uses a geomorphic systems approach that emphasizes the geologic-geomorphic attributes of the units. Realm, major division, province, and section are formulated by subdividing large units into smaller ones. For the larger units we have followed Fenneman's delineations, which are well established in the North American literature. Areas and districts are aggregated into regions and regions into sections. Units smaller than areas have, in practice, been subdivided into zones and smaller units if required. We developed the theoretical framework embodied in this classification from practical applications aimed at land use planning and land management in Maryland (eastern Piedmont Province near Baltimore) and Utah (eastern Uinta Mountains). ?? 1991 Springer-Verlag New York Inc.
A theoretical analysis of the electrogastrogram (EGG).
Calder, Stefan; Cheng, Leo K; Peng Du
2014-01-01
In this study, a boundary element model was developed to investigate the relationship between the gastric electrical activity, also known as slow waves, and the electrogastrogram (EGG). A dipole was calculated to represent the equivalent net activity of gastric slow waves. The dipole was then placed in an anatomically-realistic torso model to simulate EGG. The torso model was constructed from a laser-scanned geometry of an adult male torso phantom with 190 electrode sites equally distributed around the torso so that simulated EGG could be directly compared between the physical model and the mathematical model. The results were analyzed using the Fast Fourier Transforms (FFT), spatial distribution of EGG potential and a resultant EGG based on a 3-lead configuration. The FFT results showed both the dipole and EGG contained identical dominant frequency component of 3 cycles per minute (cpm), with this result matching known physiological phenomenon. The -3 dB point of the EGG was 110 mm from the region directly above the dipole source. Finally, the results indicated that electrode coupling could theoretically be used in a similar fashion to ECG coupling to gain greater understanding of how EGG correlate to gastric slow waves.
Catalytic efficiency of enzymes: a theoretical analysis.
Hammes-Schiffer, Sharon
2013-03-26
This brief review analyzes the underlying physical principles of enzyme catalysis, with an emphasis on the role of equilibrium enzyme motions and conformational sampling. The concepts are developed in the context of three representative systems, namely, dihydrofolate reductase, ketosteroid isomerase, and soybean lipoxygenase. All of these reactions involve hydrogen transfer, but many of the concepts discussed are more generally applicable. The factors that are analyzed in this review include hydrogen tunneling, proton donor-acceptor motion, hydrogen bonding, pKa shifting, electrostatics, preorganization, reorganization, and conformational motions. The rate constant for the chemical step is determined primarily by the free energy barrier, which is related to the probability of sampling configurations conducive to the chemical reaction. According to this perspective, stochastic thermal motions lead to equilibrium conformational changes in the enzyme and ligands that result in configurations favorable for the breaking and forming of chemical bonds. For proton, hydride, and proton-coupled electron transfer reactions, typically the donor and acceptor become closer to facilitate the transfer. The impact of mutations on the catalytic rate constants can be explained in terms of the factors enumerated above. In particular, distal mutations can alter the conformational motions of the enzyme and therefore the probability of sampling configurations conducive to the chemical reaction. Methods such as vibrational Stark spectroscopy, in which environmentally sensitive probes are introduced site-specifically into the enzyme, provide further insight into these aspects of enzyme catalysis through a combination of experiments and theoretical calculations.
Space Debris Removal: A Game Theoretic Analysis
Directory of Open Access Journals (Sweden)
Richard Klima
2016-08-01
Full Text Available We analyse active space debris removal efforts from a strategic, game-theoretical perspective. Space debris is non-manoeuvrable, human-made objects orbiting Earth, which pose a significant threat to operational spacecraft. Active debris removal missions have been considered and investigated by different space agencies with the goal to protect valuable assets present in strategic orbital environments. An active debris removal mission is costly, but has a positive effect for all satellites in the same orbital band. This leads to a dilemma: each agency is faced with the choice between the individually costly action of debris removal, which has a positive impact on all players; or wait and hope that others jump in and do the ‘dirty’ work. The risk of the latter action is that, if everyone waits, the joint outcome will be catastrophic, leading to what in game theory is referred to as the ‘tragedy of the commons’. We introduce and thoroughly analyse this dilemma using empirical game theory and a space debris simulator. We consider two- and three-player settings, investigate the strategic properties and equilibria of the game and find that the cost/benefit ratio of debris removal strongly affects the game dynamics.
Theoretical analysis of HVAC duct hanger systems
Miller, R. D.
1987-01-01
Several methods are presented which, together, may be used in the analysis of duct hanger systems over a wide range of frequencies. The finite element method (FEM) and component mode synthesis (CMS) method are used for low- to mid-frequency range computations and have been shown to yield reasonably close results. The statistical energy analysis (SEA) method yields predictions which agree with the CMS results for the 800 to 1000 Hz range provided that a sufficient number of modes participate. The CMS approach has been shown to yield valuable insight into the mid-frequency range of the analysis. It has been demonstrated that it is possible to conduct an analysis of a duct/hanger system in a cost-effective way for a wide frequency range, using several methods which overlap for several frequency bands.
Theoretical reflections on Wilhelm Reich's Character Analysis.
Shapiro, David
2002-01-01
The ideas contained in Wilhelm Reich's Character Analysis, while very influential, have not been thoroughly exploited in psychoanalysis and psychotherapy. These ideas, aimed particularly at producing genuine change rather than mere intellectual understanding, are reexamined. Further implications of them are discussed.
Game Theoretic Risk Analysis of Security Threats
Bier, Vicki M
2008-01-01
Introduces reliability and risk analysis in the face of threats by intelligent agents. This book covers applications to networks, including problems in both telecommunications and transportation. It provides a set of tools for applying game theory TO reliability problems in the presence of intentional, intelligent threats
Active disturbance rejection control: methodology and theoretical analysis.
Huang, Yi; Xue, Wenchao
2014-07-01
The methodology of ADRC and the progress of its theoretical analysis are reviewed in the paper. Several breakthroughs for control of nonlinear uncertain systems, made possible by ADRC, are discussed. The key in employing ADRC, which is to accurately determine the "total disturbance" that affects the output of the system, is illuminated. The latest results in theoretical analysis of the ADRC-based control systems are introduced.
Hedging rule for reservoir operations: 1. A theoretical analysis
You, Jiing-Yun; Cai, Ximing
2008-01-01
Hedging rule policies for reservoir operations accept small deficits in current supply to reduce the probability of a severe water shortage later. This paper expands a theoretical analysis and develops a conceptual two-period model for reservoir operation with hedging that includes uncertain future reservoir inflow explicitly. Extended analysis of the model properties and influencing factors is presented with a general utility function, addressing (1) the starting and ending water availability for hedging, (2) the range of hedging that is related to water demand levels, (3) inflow uncertainty, and (4) evaporation loss. Some intuitive knowledge on reservoir operation is proved or reconfirmed analytically; and new knowledge is derived. This theoretical analysis provides an updated basis for further theoretical study, and the theoretical findings can be used to improve numerical modeling for reservoir operation.
Directory of Open Access Journals (Sweden)
Anderson Tiago Peixoto Gonçalves
2016-08-01
Full Text Available This theoretical essay aims to reflect on three models of text interpretation used in qualitative research, which is often confused in its concepts and methodologies (Content Analysis, Discourse Analysis, and Conversation Analysis. After the presentation of the concepts, the essay proposes a preliminary discussion on conceptual and theoretical methodological differences perceived between them. A review of the literature was performed to support the conceptual and theoretical methodological discussion. It could be verified that the models have differences related to the type of strategy used in the treatment of texts, the type of approach, and the appropriate theoretical position.
Medial Cochlear Efferent Function: A Theoretical Analysis
Mountain, David C.
2011-11-01
Since the discovery of the cochlear efferent system, many hypotheses have been put forth for its function. These hypotheses for its function range from protecting the cochlea from over stimulation to improving the detection of sounds in noise. It is known that the medial efferent system innervates the outer hair cells and that stimulation of this system reduces basilar membrane and auditory nerve sensitivity which suggests that this system acts to decrease the gain of the cochlear amplifier. Here I present modeling results as well as analysis of published experimental data that suggest that the function of the medial efferent reflex is to decrease the cochlear amplifier gain by just the right amount so that the nonlinearity in the basilar membrane response lines up perfectly with the inner hair cell nonlinear transduction process to produce a hair cell receptor potential that is proportional to the logarithm of the sound pressure level.
Gender and Physics: a Theoretical Analysis
Rolin, Kristina
This article argues that the objections raised by Koertge (1998), Gross and Levitt (1994), and Weinberg (1996) against feminist scholarship on gender and physics are unwarranted. The objections are that feminist science studies perpetuate gender stereotypes, are irrelevant to the content of physics, or promote epistemic relativism. In the first part of this article I argue that the concept of gender, as it has been developed in feminist theory, is a key to understanding why the first objection is misguided. Instead of reinforcing gender stereotypes, feminist science studies scholars can formulate empirically testable hypotheses regarding local and contested beliefs about gender. In the second part of this article I argue that a social analysis of scientific knowledge is a key to understanding why the second and the third objections are misguided. The concept of gender is relevant for understanding the social practice of physics, and the social practice of physics can be of epistemic importance. Instead of advancing epistemic relativism, feminist science studies scholars can make important contributions to a subfield of philosophy called social epistemology.
Theoretical Analysis of Reinforcement Tunnel Lining Corrosion
Directory of Open Access Journals (Sweden)
ZhiQiang Zhangand
2013-05-01
Full Text Available The main cause of ageing damage in reinforced concrete structures is reinforcement corrosion. Damage can be detected visually as coincident cracks along the reinforcement bar, which are significant of both reduction of the re-bar, cross-section and loss of bond strength for reinforced concrete. The reinforced concrete is one of the most widely used engineering materials as final lining of tunnels. The corrosion is common durability problems that have significant effect on the tunnel performance. This study intends to analysis reinforcement concrete corrosion at the tunnel lining by applying temperature expansion theory on steel through numerical simulation process, with expansive force effect. The thickness of concrete cover and the diameter of steel bar have an impact on the stress for reinforcement concrete during propagation of corrosion process. The corrosion cracks appear at the corner of a tunnel lining then in invert and vault because the maximum stress will be in the corner then in invert and vault. The internal force in the concrete lining changes differently when the corrosion rate change.
BRIEF ANALYSIS ON THEORETIC EVIDENCE OF FOUR-GATE POINTS IN TREATMENT OF DISEASE
Institute of Scientific and Technical Information of China (English)
无
2006-01-01
In the present paper, the authors expound the approaches of four-gate points on treatment of diseases and the relevant theoretic evidence. The analysis and discussion were carried on in the aspects of the origins of four-gate points and the relationships of four-gate points with primary qi, running course of meridian, qi and blood and biaoben qijie of meridian and collateral. Being the major points in clinic, fourgate points provide extensive indications and good therapeutic effects, which are supported thoroughly by the theoretic evidence.
Category theoretic analysis of hierarchical protein materials and social networks.
Directory of Open Access Journals (Sweden)
David I Spivak
Full Text Available Materials in biology span all the scales from Angstroms to meters and typically consist of complex hierarchical assemblies of simple building blocks. Here we describe an application of category theory to describe structural and resulting functional properties of biological protein materials by developing so-called ologs. An olog is like a "concept web" or "semantic network" except that it follows a rigorous mathematical formulation based on category theory. This key difference ensures that an olog is unambiguous, highly adaptable to evolution and change, and suitable for sharing concepts with other olog. We consider simple cases of beta-helical and amyloid-like protein filaments subjected to axial extension and develop an olog representation of their structural and resulting mechanical properties. We also construct a representation of a social network in which people send text-messages to their nearest neighbors and act as a team to perform a task. We show that the olog for the protein and the olog for the social network feature identical category-theoretic representations, and we proceed to precisely explicate the analogy or isomorphism between them. The examples presented here demonstrate that the intrinsic nature of a complex system, which in particular includes a precise relationship between structure and function at different hierarchical levels, can be effectively represented by an olog. This, in turn, allows for comparative studies between disparate materials or fields of application, and results in novel approaches to derive functionality in the design of de novo hierarchical systems. We discuss opportunities and challenges associated with the description of complex biological materials by using ologs as a powerful tool for analysis and design in the context of materiomics, and we present the potential impact of this approach for engineering, life sciences, and medicine.
Extension of a System Level Tool for Component Level Analysis
Majumdar, Alok; Schallhorn, Paul
2002-01-01
This paper presents an extension of a numerical algorithm for network flow analysis code to perform multi-dimensional flow calculation. The one dimensional momentum equation in network flow analysis code has been extended to include momentum transport due to shear stress and transverse component of velocity. Both laminar and turbulent flows are considered. Turbulence is represented by Prandtl's mixing length hypothesis. Three classical examples (Poiseuille flow, Couette flow and shear driven flow in a rectangular cavity) are presented as benchmark for the verification of the numerical scheme.
de Wieclawik, W; Vieu, C
1976-01-01
The Ericson's statistical method is applied extensively to the analysis of experimental and theoretical negative parity levels of odd mass Tl, Au and Ir isotopes. This analysis shows the importance of such method as a valuable tool for detecting systematic insufficiencies of experimental data as well as for testing the overall descriptions of a nucleus given by different nuclear models.
Extensions of nonlinear error propagation analysis for explicit pseudodynamic testing
Institute of Scientific and Technical Information of China (English)
Shuenn-Yih Chang
2009-01-01
Two important extensions of a technique to perform a nonlinear error propagation analysis for an explicit pseudodynamic algorithm (Chang, 2003) are presented. One extends the stability study from a given time step to a complete step-by-step integration procedure. It is analytically proven that ensuring stability conditions in each time step leads to a stable computation of the entire step-by-step integration procedure. The other extension shows that the nonlinear error propagation results, which are derived for a nonlinear single degree of freedom (SDOF) system, can be applied to a nonlinear multiple degree of freedom (MDOF) system. This application is dependent upon the determination of the natural frequencies of the system in each time step, since all the numerical properties and error propagation properties in the time step are closely related to these frequencies. The results are derived from the step degree of nonlinearity. An instantaneous degree of nonlinearity is introduced to replace the step degree of nonlinearity and is shown to be easier to use in practice. The extensions can be also applied to the results derived from a SDOF system based on the instantaneous degree of nonlinearity, and hence a time step might be appropriately chosen to perform a pseudodynamic test prior to testing.
ETRAN--R Extension Package for Eye Tracking Results Analysis.
Zhegallo, Alexander V; Marmalyuk, Pavel A
2015-01-01
Novel open source R extension package for general-purpose eye tracking results analysis proposed. Now supported features are data loading from SMI eye trackers, different methods of fixations detection, various imaging techniques for raw data, and detected fixations (time sequence, scanpath, heatmap, and dynamic visualization). The modular structure of the package and a detailed description of each function provide a convenient way to further extend the functionality. Effective use of package requires knowledge of R programming language and environment. © The Author(s) 2015.
A Theoretical and Empirical Analysis of Expected Sarsa
van Seijen, Harm; van Hasselt, Hado; Whiteson, Shimon; Wiering, Marco
2009-01-01
This paper presents a theoretical and empirical analysis of Expected Sarsa, a variation on Sarsa, the classic on policy temporal-difference method for model-free reinforcement learning. Expected Sarsa exploits knowledge about stochasticity in the behavior policy to perform updates with lower varianc
A theoretical and empirical analysis of expected sarsa
Seijen, H.H. van; Hasselt, H. van; Whiteson, S.; Wiering, M.
2009-01-01
This paper presents a theoretical and empirical analysis of Expected Sarsa, a variation on Sarsa, the classic onpolicy temporal-difference method for model-free reinforcement learning. Expected Sarsa exploits knowledge about stochasticity in the behavior policy to perform updates with lower variance
Theoretical Analysis and Restructuring of Capacity Building for Sustainable Development
Institute of Scientific and Technical Information of China (English)
ZHOU Hailin; HUANG Jing
2001-01-01
On the basis of the interpretation of capacity building for sustainable development (CBSD) provided in Agenda 21, the paper develops a definition of CBSD for the first time by giving a full account of this basic concept and its essential connotation. Besides, a theoretical analysis of the importance, approach and role of capacity building in implementing the strategy of sustainable development is presented.
PRICE DISCRIMINATION AND MARKET POWER: A THEORETICAL ANALYSIS
Directory of Open Access Journals (Sweden)
Olga Smirnova
2015-07-01
Full Text Available This paper analyzes the contemporary theoretical and empirical research in the field of impact assessment of market power and conclusions about the possibilities of the company to implement price discrimination in different market structures. The results of the analysis allow to evaluate current approaches to antitrust regulation of price discrimination.
A Divergence Statistics Extension to VTK for Performance Analysis.
Energy Technology Data Exchange (ETDEWEB)
Pebay, Philippe Pierre; Bennett, Janine Camille
2015-02-01
This report follows the series of previous documents ([PT08, BPRT09b, PT09, BPT09, PT10, PB13], where we presented the parallel descriptive, correlative, multi-correlative, principal component analysis, contingency, k -means, order and auto-correlative statistics engines which we developed within the Visualization Tool Kit ( VTK ) as a scalable, parallel and versatile statistics package. We now report on a new engine which we developed for the calculation of divergence statistics, a concept which we hereafter explain and whose main goal is to quantify the discrepancy, in a stasticial manner akin to measuring a distance, between an observed empirical distribution and a theoretical, "ideal" one. The ease of use of the new diverence statistics engine is illustrated by the means of C++ code snippets. Although this new engine does not yet have a parallel implementation, it has already been applied to HPC performance analysis, of which we provide an example.
A Divergence Statistics Extension to VTK for Performance Analysis
Energy Technology Data Exchange (ETDEWEB)
Pebay, Philippe Pierre [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Bennett, Janine Camille [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
2015-02-01
This report follows the series of previous documents ([PT08, BPRT09b, PT09, BPT09, PT10, PB13], where we presented the parallel descriptive, correlative, multi-correlative, principal component analysis, contingency, k -means, order and auto-correlative statistics engines which we developed within the Visualization Tool Kit ( VTK ) as a scalable, parallel and versatile statistics package. We now report on a new engine which we developed for the calculation of divergence statistics, a concept which we hereafter explain and whose main goal is to quantify the discrepancy, in a stasticial manner akin to measuring a distance, between an observed empirical distribution and a theoretical, "ideal" one. The ease of use of the new diverence statistics engine is illustrated by the means of C++ code snippets. Although this new engine does not yet have a parallel implementation, it has already been applied to HPC performance analysis, of which we provide an example.
LOOS: an extensible platform for the structural analysis of simulations.
Romo, Tod D; Grossfield, Alan
2009-01-01
We have developed LOOS (Lightweight Object-Oriented Structure-analysis library) as an object-oriented library designed to facilitate the rapid development of tools for the structural analysis of simulations. LOOS supports the native file formats of most common simulation packages including AMBER, CHARMM, CNS, Gromacs, NAMD, Tinker, and X-PLOR. Encapsulation and polymorphism are used to simultaneously provide a stable interface to the programmer and make LOOS easily extensible. A rich atom selection language based on the C expression syntax is included as part of the library. LOOS enables students and casual programmer-scientists to rapidly write their own analytical tools in a compact and expressive manner resembling scripting. LOOS is written in C++ and makes extensive use of the Standard Template Library and Boost, and is freely available under the GNU General Public License (version 3) LOOS has been tested on Linux and MacOS X, but is written to be portable and should work on most Unix-based platforms.
Category theoretic analysis of single-photon decision maker
Kim, Makoto Naruse Song-Ju; Berthel, Martin; Drezet, Aurélien; Huant, Serge; Hori, Hirokazu
2016-01-01
Decision making is a vital function in the era of artificial intelligence; however, its physical realizations and their theoretical fundamentals are not yet known. In our former study [Sci. Rep. 5, 513253 (2015)], we demonstrated that single photons can be used to make decisions in uncertain, dynamically changing environments. The multi-armed bandit problem was successfully solved using the dual probabilistic and particle attributes of single photons. Herein, we present the category theoretic foundation of the single-photon-based decision making, including quantitative analysis that agrees well with the experimental results. The category theoretic model unveils complex interdependencies of the entities of the subject matter in the most simplified manner, including a dynamically changing environment. In particular, the octahedral structure in triangulated categories provides a clear understanding of the underlying mechanisms of the single-photon decision maker. This is the first demonstration of a category the...
1979-01-01
User power, duration, and orbit requirements, which were the prime factors influencing power extension package (PEP) design, are discussed. A representative configuration of the PEP concept is presented and the major elements of the system are described as well as the PEP-to-Orbiter and remote manipulator interface provisions.
SiSn diodes: Theoretical analysis and experimental verification
Hussain, Aftab M.
2015-08-24
We report a theoretical analysis and experimental verification of change in band gap of silicon lattice due to the incorporation of tin (Sn). We formed SiSn ultra-thin film on the top surface of a 4 in. silicon wafer using thermal diffusion of Sn. We report a reduction of 0.1 V in the average built-in potential, and a reduction of 0.2 V in the average reverse bias breakdown voltage, as measured across the substrate. These reductions indicate that the band gap of the silicon lattice has been reduced due to the incorporation of Sn, as expected from the theoretical analysis. We report the experimentally calculated band gap of SiSn to be 1.11 ± 0.09 eV. This low-cost, CMOS compatible, and scalable process offers a unique opportunity to tune the band gap of silicon for specific applications.
Theoretical Analysis and Simulation of Jacking Procedure of Pantadome System
Institute of Scientific and Technical Information of China (English)
WANG Xiaodun; SHI Yongjiu; WANG Yuanqing; Kawaguchi Mamoru
2005-01-01
In order to obtain the principle of Pantadome lifting process and make theoretical foundation for practical applications, the core idea of Pantadome was introduced, which is to make a structure become a mechanism by temporarily removing some members during the process of construction.The abstract motion model was built. By determining the change of the coordinates of the hinge joint and that of each point of the structure, simulative analysis of the mechanical motion of Pantadome was realized. Then general program that simulates the lifting process of Pantadome was developed based on AutoCAD environment by Auto Lisp language. By completing the theoretical analysis of the lifting process of Pantadome, three-dimensional simulation of the lifting process of Pantadome was realized. And it is successfully applied to bidding work of practical engineering.
Theoretical Analysis of Heuristic Search Methods for Online POMDPs.
Ross, Stéphane; Pineau, Joelle; Chaib-Draa, Brahim
2008-01-01
Planning in partially observable environments remains a challenging problem, despite significant recent advances in offline approximation techniques. A few online methods have also been proposed recently, and proven to be remarkably scalable, but without the theoretical guarantees of their offline counterparts. Thus it seems natural to try to unify offline and online techniques, preserving the theoretical properties of the former, and exploiting the scalability of the latter. In this paper, we provide theoretical guarantees on an anytime algorithm for POMDPs which aims to reduce the error made by approximate offline value iteration algorithms through the use of an efficient online searching procedure. The algorithm uses search heuristics based on an error analysis of lookahead search, to guide the online search towards reachable beliefs with the most potential to reduce error. We provide a general theorem showing that these search heuristics are admissible, and lead to complete and ε-optimal algorithms. This is, to the best of our knowledge, the strongest theoretical result available for online POMDP solution methods. We also provide empirical evidence showing that our approach is also practical, and can find (provably) near-optimal solutions in reasonable time.
Theoretical analysis of radiographic images by nonstationary Poisson processes
Energy Technology Data Exchange (ETDEWEB)
Tanaka, K.; Uchida, S. (Gifu Univ. (Japan)); Yamada, I.
1980-12-01
This paper deals with the noise analysis of radiographic images obtained in the usual fluorescent screen-film system. The theory of nonstationary Poisson processes is applied to the analysis of the radiographic images containing the object information. The ensemble averages, the autocorrelation functions, and the Wiener spectrum densities of the light-energy distribution at the fluorescent screen and of the film optical-density distribution are obtained. The detection characteristics of the system are evaluated theoretically. Numerical examples one-dimensional image are shown and the results are compared with those obtained under the assumption that the object image is related to the background noise by the additive process.
Theoretical Analysis of Radiographic Images by Nonstationary Poisson Processes
Tanaka, Kazuo; Yamada, Isao; Uchida, Suguru
1980-12-01
This paper deals with the noise analysis of radiographic images obtained in the usual fluorescent screen-film system. The theory of nonstationary Poisson processes is applied to the analysis of the radiographic images containing the object information. The ensemble averages, the autocorrelation functions, and the Wiener spectrum densities of the light-energy distribution at the fluorescent screen and of the film optical-density distribution are obtained. The detection characteristics of the system are evaluated theoretically. Numerical examples of the one-dimensional image are shown and the results are compared with those obtained under the assumption that the object image is related to the background noise by the additive process.
A Theoretical Analysis of Why Hybrid Ensembles Work
Directory of Open Access Journals (Sweden)
Kuo-Wei Hsu
2017-01-01
Full Text Available Inspired by the group decision making process, ensembles or combinations of classifiers have been found favorable in a wide variety of application domains. Some researchers propose to use the mixture of two different types of classification algorithms to create a hybrid ensemble. Why does such an ensemble work? The question remains. Following the concept of diversity, which is one of the fundamental elements of the success of ensembles, we conduct a theoretical analysis of why hybrid ensembles work, connecting using different algorithms to accuracy gain. We also conduct experiments on classification performance of hybrid ensembles of classifiers created by decision tree and naïve Bayes classification algorithms, each of which is a top data mining algorithm and often used to create non-hybrid ensembles. Therefore, through this paper, we provide a complement to the theoretical foundation of creating and using hybrid ensembles.
Theoretical analysis on x-ray cylindrical grating interferometer
Cong, Wenxiang; Wang, Ge
2015-01-01
Grating interferometer is a state of art x-ray imaging approach, which can simultaneously acquire information of x-ray attenuation, phase shift, and small angle scattering. This approach is very sensitive to micro-structural variation and offers superior contrast resolution for biological soft tissues. The present grating interferometer often uses flat gratings, with serious limitations in the field of view and the flux of photons. The use of curved gratings allows perpendicular incidence of x-rays on the gratings, and gives higher visibility over a larger field of view than a conventional interferometer with flat gratings. In the study, we present a rigorous theoretical analysis of the self-imaging of curved transmission gratings based on Rayleigh-Sommerfeld diffraction. Numerical simulations have demonstrated the self-imaging phenomenon of cylindrical grating interferometer. The theoretical results are in agreement with the results of numerical simulations.
Theoretical analysis of balanced truncation for linear switched systems
DEFF Research Database (Denmark)
Petreczky, Mihaly; Wisniewski, Rafal; Leth, John-Josef
2012-01-01
In this paper we present theoretical analysis of model reduction of linear switched systems based on balanced truncation, presented in [1,2]. More precisely, (1) we provide a bound on the estimation error using L2 gain, (2) we provide a system theoretic interpretation of grammians...... for showing this independence is realization theory of linear switched systems. [1] H. R. Shaker and R. Wisniewski, "Generalized gramian framework for model/controller order reduction of switched systems", International Journal of Systems Science, Vol. 42, Issue 8, 2011, 1277-1291. [2] H. R. Shaker and R....... Wisniewski, "Switched Systems Reduction Framework Based on Convex Combination of Generalized Gramians", Journal of Control Science and Engineering, 2009....
Information-Theoretical Complexity Analysis of Selected Elementary Chemical Reactions
Molina-Espíritu, M.; Esquivel, R. O.; Dehesa, J. S.
We investigate the complexity of selected elementary chemical reactions (namely, the hydrogenic-abstraction reaction and the identity SN2 exchange reaction) by means of the following single and composite information-theoretic measures: disequilibrium (D), exponential entropy(L), Fisher information (I), power entropy (J), I-D, D-L and I-J planes and Fisher-Shannon (FS) and Lopez-Mancini-Calbet (LMC) shape complexities. These quantities, which are functionals of the one-particle density, are computed in both position (r) and momentum (p) spaces. The analysis revealed that the chemically significant regions of these reactions can be identified through most of the single information-theoretic measures and the two-component planes, not only the ones which are commonly revealed by the energy, such as the reactant/product (R/P) and the transition state (TS), but also those that are not present in the energy profile such as the bond cleavage energy region (BCER), the bond breaking/forming regions (B-B/F) and the charge transfer process (CT). The analysis of the complexities shows that the energy profile of the abstraction reaction bears the same information-theoretical features of the LMC and FS measures, however for the identity SN2 exchange reaction does not hold a simple behavior with respect to the LMC and FS measures. Most of the chemical features of interest (BCER, B-B/F and CT) are only revealed when particular information-theoretic aspects of localizability (L or J), uniformity (D) and disorder (I) are considered.
Jorgensen, Kameron R; Wilson, Angela K
2012-09-15
Discrepancies are noted in the implementation and presentation of the ccCA methodology in a previous publication, "Extensive Theoretical Studies of a New Energetic Material: Tetrazino-tetrazine-tetraoxide (TTTO)" by Xinli Song, Jicun Li, Hua Hou, and Baoshan Wang. The enthalpy of formation for TTTO has been re-evaluated using the correct implementation of the ccCA methodology, demonstrating the results to be comparable to those of other ab initio composite methods. Copyright © 2012 Wiley Periodicals, Inc.
Theoretical Analysis and Simulation of BJFET Obstructive Characteristics
Institute of Scientific and Technical Information of China (English)
ZENG Yun; YAN Min; YAN Yong-hong; FAN Wei
2005-01-01
A new bipolar junction field-effect transistor (BJFET) was described. The theoretical analysis and computer simulation of BJFET obstructive characteristic are achieved. The gate bias voltage affects the BJFET obstructive voltage greatly. The BJFET obstructive characteristic is relevant to structure parameters of channel width W and channel length L.The decrease-bias-voltage operation can weaken the device obstructive characteristic. The forward turn in device forward obstructive region can also affect the BJFET obstructive characteristic. BJFET has a good high temperature obstructive characteristic and can be applying to high temperature status as high voltage switch devices.
Theoretical analysis of bubble nucleation in GASAR materials
Institute of Scientific and Technical Information of China (English)
刘源; 李言祥
2003-01-01
Nucleation of gaseous hydrogen bubbles is the initial stage of GASAR process. Through the theoretical analysis, it has been identified that heterogeneous nucleation of bubbles as caps on the solid surfaces of impurities is impossible and only the heterogeneous nucleation in pits and cracks in impurities is the most feasible way in the GASAR process. The results also show that the probability of bubble nucleation progressively decreases from Al, Cu and Ni to Fe molten metal, which is the result of the increasing adhesion work of liquid metal on alumina.
Analysis of search-extension method for finding multiple solutions of nonlinear problem
Institute of Scientific and Technical Information of China (English)
2008-01-01
For numerical computations of multiple solutions of the nonlinear elliptic problemΔu+ f（u）=0 inΩ, u=0 onΓ, a search-extension method （SEM） was proposed and systematically studied by the authors. This paper shall complete its theoretical analysis. It is assumed that the nonlinearity is non-convex and its solution is isolated, under some conditions the corresponding linearized problem has a unique solution. By use of the compactness of the solution family and the contradiction argument, in general conditions, the high order regularity of the solution u∈H1+α,α>0 is proved. Assume that some initial value searched by suitably many eigenbases is already fallen into the neighborhood of the isolated solution, then the optimal error estimates of its nonlinear finite element approximation are shown by the duality argument and continuation method.
THEORETICAL ANALYSIS STUDY OF FORMATION OF FUTURE LEGAL LAWYERS
Directory of Open Access Journals (Sweden)
Eugene Stepanovich Shevlakov
2015-09-01
Full Text Available The article deals with topical issues of formation of legal consciousness of future lawyers in high school. Obtained kinds of legal consciousness of future lawyers, determined its structure. Dedicated components of justice are mutually reinforcing, and provide an opportunity for further development of the personality of the future specialist, their personal growth.The purpose: to carry out theoretical analysis of the problem of formation of legal consciousness of future lawyers.The novelty is based. On the analysis of theoretical appro-aches of pedagogy, psychology, law, the notion of «lawfulness of the future of the law student», which is regarded as a form of social consciousness, which is a set of legal views and feelings, expressing the attitude to the law and legal phenomena that have regulatory in character and which includes know-ledge of legal phenomena and their evaluation from the point of view of fairness and justice, formed in the process of studying in the University.Results: this article analyzes different approaches to understanding the content and essence of the concept of legal consciousness of the legal profession. Define the types and structure of legal consciousness of future lawyers.
Inner strength--a theoretical analysis of salutogenic concepts.
Lundman, Berit; Aléx, Lena; Jonsén, Elisabeth; Norberg, Astrid; Nygren, Björn; Santamäki Fischer, Regina; Strandberg, Gunilla
2010-02-01
Theoretical and empirical overlaps between the concepts of resilience, sense of coherence, hardiness, purpose in life, and self-transcendence have earlier been described as some kind of inner strength, but no studies have been found that focus on what attributes these concepts have in common. The objective of this study was to perform a theoretical analysis of the concepts of resilience, sense of coherence, hardiness, purpose in life, and self-transcendence, in order to identify their core dimensions in an attempt to get an overarching understanding of inner strength. PRINT METHOD: An analysis inspired by the procedure of meta-theory construction was performed. The main questions underlying the development of the concepts, the major paradigms and the most prominent assumptions, the critical attributes and the characteristics of the various concepts were identified. The analysis resulted in the identification of four core dimensions of inner strength and the understanding that inner strength relies on the interaction of these dimensions: connectedness, firmness, flexibility, and creativity. These dimensions were validated through comparison with the original descriptions of the concepts. An overarching understanding of inner strength is that it means both to stand steady, to be firm, with both feet on the ground and to be connected to; family, friends, society, nature and spiritual dimensions and to be able to transcend. Having inner strength is to be creative and stretchable, which is to believe in own possibilities to act and to make choices and influence life's trajectory in a perceived meaningful direction. Inner strength is to shoulder responsibility for oneself and others, to endure and deal with difficulties and adversities. This knowledge about inner strength will raise the awareness of the concept and, in turn, hopefully increase our potential to support people's inner strength. Copyright 2009 Elsevier Ltd. All rights reserved.
SOCIOLOGICAL UNDERSTANDING OF INTERNET: THEORETICAL APPROACHES TO THE NETWORK ANALYSIS
Directory of Open Access Journals (Sweden)
D. E. Dobrinskaya
2016-01-01
Full Text Available Internet studies are carried out by various scientific disciplines and in different research perspectives. Sociological studies of the Internet deal with a new technology, a revolutionary means of mass communication and a social space. There is a set of research difficulties associated with the Internet. Firstly, the high speed and wide spread of Internet technologies’ development. Secondly, the collection and filtration of materials concerning with Internet studies. Lastly, the development of new conceptual categories, which are able to reflect the impact of the Internet development in contemporary world. In that regard the question of the “network” category use is essential. Network is the base of Internet functioning, on the one hand. On the other hand, network is the ground for almost all social interactions in modern society. So such society is called network society. Three theoretical network approaches in the Internet research case are the most relevant: network society theory, social network analysis and actor-network theory. Each of these theoretical approaches contributes to the study of the Internet. They shape various images of interactions between human beings in their entity and dynamics. All these approaches also provide information about the nature of these interactions.
Le Guyader, P; Trelles, F; Savard, P
2001-10-01
The passive electrical properties of cardiac tissue, such as the intracellular and interstitial conductivities along the longitudinal and transverse axes, have not been often measured because intracellular electrodes are usually needed for these measurements. In this paper, we present a theoretical analysis of two myocardial models developed to estimate these properties by analyzing potentials recorded with a pair of extracellular electrodes while injecting alternating current between another pair of electrodes. First, the cardiac tissue is represented by a standard bidomain model which includes a membrane capacitance; second, this model is modified by adding an intracellular capacitance representing the intercalated disks. Numerical solutions are computed with a fast Fourier transform algorithm without constraining the anisotropy ratios of the interstitial and intracellular domains. We systematically investigate the effects of changes in the bidomain parameters on the voltage-to-current ratio curves. We also demonstrate how the bidomain parameters can be theoretically estimated by fitting, with a modified Shor's r algorithm, the simulated potentials along the longitudinal and transverse axes for different frequencies between 10 and 10,000 Hz. An important finding is that the interelectrode distance must be similar to the myocardial space constant so as to obtain frequency dependent measurements.
Theoretical Analysis of Dynamic Processes for Interacting Molecular Motors.
Teimouri, Hamid; Kolomeisky, Anatoly B; Mehrabiani, Kareem
2015-02-13
Biological transport is supported by collective dynamics of enzymatic molecules that are called motor proteins or molecular motors. Experiments suggest that motor proteins interact locally via short-range potentials. We investigate the fundamental role of these interactions by analyzing a new class of totally asymmetric exclusion processes where interactions are accounted for in a thermodynamically consistent fashion. It allows us to connect explicitly microscopic features of motor proteins with their collective dynamic properties. Theoretical analysis that combines various mean-field calculations and computer simulations suggests that dynamic properties of molecular motors strongly depend on interactions, and correlations are stronger for interacting motor proteins. Surprisingly, it is found that there is an optimal strength of interactions (weak repulsion) that leads to a maximal particle flux. It is also argued that molecular motors transport is more sensitive to attractive interactions. Applications of these results for kinesin motor proteins are discussed.
Theoretical Analysis of Rayleigh Backscattering Noise in Fiber Raman Amplifiers
Institute of Scientific and Technical Information of China (English)
无
2005-01-01
In this paper, a new theoretical model for Rayleigh backscattering (RB) analysis of fiber Raman amplifiers is proposed. The model includes all the interactions among the pumps, signals, and all orders of RB. The results show that the higher order RB has a negligible influence on the performance of the amplifier. The co-propagating and counterpropagating RB power of the signal grow quadratically with the net-gain of the amplifier. The signal to double Rayleigh backscattering noise ratio (OSNRDRB ) of backward-pumped FRAs is better than that of the forward-pumped ones at high net-gain level (＞ 13 dB), while at low net-gain level the OSNRDrb of the forward-pumped FRAs is slightly better than that of the backward-pumped ones.
Two-Dimensional Electronic Spectroscopy Using Incoherent Light: Theoretical Analysis
Turner, Daniel B; Sutor, Erika J; Hendrickson, Rebecca A; Gealy, M W; Ulness, Darin J
2012-01-01
Electronic energy transfer in photosynthesis occurs over a range of time scales and under a variety of intermolecular coupling conditions. Recent work has shown that electronic coupling between chromophores can lead to coherent oscillations in two-dimensional electronic spectroscopy measurements of pigment-protein complexes measured with femtosecond laser pulses. A persistent issue in the field is to reconcile the results of measurements performed using femtosecond laser pulses with physiological illumination conditions. Noisy-light spectroscopy can begin to address this question. In this work we present the theoretical analysis of incoherent two-dimensional electronic spectroscopy, I(4) 2D ES. Simulations reveal diagonal peaks, cross peaks, and coherent oscillations similar to those observed in femtosecond two-dimensional electronic spectroscopy experiments. The results also expose fundamental differences between the femtosecond-pulse and noisy-light techniques; the differences lead to new challenges and opp...
Theoretical analysis of tsunami generation by pyroclastic flows
Watts, P.; Waythomas, C.F.
2003-01-01
Pyroclastic flows are a common product of explosive volcanism and have the potential to initiate tsunamis whenever thick, dense flows encounter bodies of water. We evaluate the process of tsunami generation by pyroclastic flow by decomposing the pyroclastic flow into two components, the dense underflow portion, which we term the pyroclastic debris flow, and the plume, which includes the surge and coignimbrite ash cloud parts of the flow. We consider five possible wave generation mechanisms. These mechanisms consist of steam explosion, pyroclastic debris flow, plume pressure, plume shear, and pressure impulse wave generation. Our theoretical analysis of tsunami generation by these mechanisms provides an estimate of tsunami features such as a characteristic wave amplitude and wavelength. We find that in most situations, tsunami generation is dominated by the pyroclastic debris flow component of a pyroclastic flow. This work presents information sufficient to construct tsunami sources for an arbitrary pyroclastic flow interacting with most bodies of water. Copyright 2003 by the American Geophysical Union.
Deep and Structured Robust Information Theoretic Learning for Image Analysis.
Deng, Yue; Bao, Feng; Deng, Xuesong; Wang, Ruiping; Kong, Youyong; Dai, Qionghai
2016-07-07
This paper presents a robust information theoretic (RIT) model to reduce the uncertainties, i.e. missing and noisy labels, in general discriminative data representation tasks. The fundamental pursuit of our model is to simultaneously learn a transformation function and a discriminative classifier that maximize the mutual information of data and their labels in the latent space. In this general paradigm, we respectively discuss three types of the RIT implementations with linear subspace embedding, deep transformation and structured sparse learning. In practice, the RIT and deep RIT are exploited to solve the image categorization task whose performances will be verified on various benchmark datasets. The structured sparse RIT is further applied to a medical image analysis task for brain MRI segmentation that allows group-level feature selections on the brain tissues.
Theoretical analysis of the coherence-brightened laser in air
Yuan, Luqi; Hokr, Brett H.; Traverso, Andrew J.; Voronine, Dmitri V.; Rostovtsev, Yuri; Sokolov, Alexei V.; Scully, Marlan O.
2013-02-01
We present a detailed theoretical study of a recent experiment [A. J. Traverso , Proc. Natl. Acad. Sci. USAPNASA60027-842410.1073/pnas.1211481109 109, 15185 (2012)] in which a laserlike source is created in air by pumping with a nanosecond pulse. The source generates radiation in the forward and backward directions. The temporal behavior of the emitted pulses is investigated for different pump shapes and durations. Our analysis indicates that the spiky emission is due to quantum coherence via cooperation between atoms of an ensemble, which leads to strong-oscillatory superfluorescence. We show that these cooperative nonadiabatic coherence effects cannot be described by rate equations and instead a full set of the Maxwell-Bloch equations must be used. We consider a range of parameters and study transitions between various regimes. Understanding these coherence-brightened processes in air should lead to improvements in environmental, atmospheric remote sensing and other applications.
How Do Pseudocapacitors Store Energy? Theoretical Analysis and Experimental Illustration.
Costentin, Cyrille; Porter, Thomas R; Savéant, Jean-Michel
2017-03-15
Batteries and electrochemical double layer charging capacitors are two classical means of storing electrical energy. These two types of charge storage can be unambiguously distinguished from one another by the shape and scan-rate dependence of their cyclic voltammetric (CV) current-potential responses. The former shows peak-shaped current-potential responses, proportional to the scan rate v or to v(1/2), whereas the latter displays a quasi-rectangular response proportional to the scan rate. On the contrary, the notion of pseudocapacitance, popularized in the 1980s and 1990s for metal oxide systems, has been used to describe a charge storage process that is faradaic in nature yet displays capacitive CV signatures. It has been speculated that a quasi-rectangular CV response resembling that of a truly capacitive response arises from a series of faradaic redox couples with a distribution of potentials, yet this idea has never been justified theoretically. We address this problem by first showing theoretically that this distribution-of-potentials approach is closely equivalent to the more physically meaningful consideration of concentration-dependent activity coefficients resulting from interactions between reactants. The result of the ensuing analysis is that, in either case, the CV responses never yield a quasi-rectangular response ∝ ν, identical to that of double layer charging. Instead, broadened peak-shaped responses are obtained. It follows that whenever a quasi-rectangular CV response proportional to scan rate is observed, such reputed pseudocapacitive behaviors should in fact be ascribed to truly capacitive double layer charging. We compare these results qualitatively with pseudocapacitor reports taken from the literature, including the classic RuO2 and MnO2 examples, and we present a quantitative analysis with phosphate cobalt oxide films. Our conclusions do not invalidate the numerous experimental studies carried out under the pseudocapacitance banner but
Comment on Pearl: Practical implications of theoretical results for causal mediation analysis.
Imai, Kosuke; Keele, Luke; Tingley, Dustin; Yamamoto, Teppei
2014-12-01
Mediation analysis has been extensively applied in psychological and other social science research. A number of methodologists have recently developed a formal theoretical framework for mediation analysis from a modern causal inference perspective. In Imai, Keele, and Tingley (2010), we have offered such an approach to causal mediation analysis that formalizes identification, estimation, and sensitivity analysis in a single framework. This approach has been used by a number of substantive researchers, and in subsequent work we have also further extended it to more complex settings and developed new research designs. In an insightful article, Pearl (2014) proposed an alternative approach that is based on a set of assumptions weaker than ours. In this comment, we demonstrate that the theoretical differences between our identification assumptions and his alternative conditions are likely to be of little practical relevance in the substantive research settings faced by most psychologists and other social scientists. We also show that our proposed estimation algorithms can be easily applied in the situations discussed in Pearl (2014). The methods discussed in this comment and many more are implemented via mediation, an open-source software (Tingley, Yamamoto, Hirose, Keele, & Imai, 2013).
Hackmann, Andreas; Ailion, David C.; Ganesan, Krishnamurthy; Laicher, Gernot; Goodrich, K. Craig; Cutillo, Antonio G.
1996-02-01
The water-biopolymer cross-relaxation model, proposed by H. E. Rorschach and C. F. Hazlewood (RH) [J. Magn. Reson.70,79 (1986)], explains the Larmor frequency dependence ofT1in many biological systems. However, the RH theory fails at low Larmor frequencies. In this paper, a more general version of the RH theory has been developed. This theory is valid at all frequencies. Use of the new expression for the spin-lattice relaxation rate (1/T1), earlier published experimental data in H2O/D2O bovine serum albumin, which had been measured over a wide frequency range (10 kHz to 100 MHz), were fitted over the entire frequency range. The agreement between theory and the experimental data is excellent. Theoretical expressions for the rotating-frame spin-lattice relaxation rate (1/T1ρ) were also obtained.
Analysis of extensive air showers with the hybrid code SENECA
Ortiz, J A; Medina-Tanco, G; Ortiz, Jeferson A.; Souza, Vitor de; Medina-Tanco, Gustavo
2005-01-01
The ultrahigh energy tail of the cosmic ray spectrum has been explored with unprecedented detail. For this reason, new experiments are exerting a severe pressure on extensive air shower modeling. Detailed fast codes are in need in order to extract and understand the richness of information now available. In this sense we explore the potential of SENECA, an efficient hybrid tridimensional simulation code, as a valid practical alternative to full Monte Carlo simulations of extensive air showers generated by ultrahigh energy cosmic rays. We discuss the influence of this approach on the main longitudinal characteristics of proton, iron nucleus and gamma induced air showers for different hadronic interaction models. We also show the comparisons of our predictions with those of CORSIKA code.
Analysis of extensive air showers with the hybrid code SENECA
Ortiz, Jeferson A.; de Souza, Vitor; Medina-Tanco, Gustavo
The ultrahigh energy tail of the cosmic ray spectrum has been explored with unprecedented detail. For this reason, new experiments are exerting a severe pressure on extensive air shower modeling. Detailed fast codes are in need in order to extract and understand the richness of information now available. In this sense we explore the potential of SENECA, an efficient hybrid tridimensional simulation code, as a valid practical alternative to full Monte Carlo simulations of extensive air showers generated by ultrahigh energy cosmic rays. We discuss the influence of this approach on the main longitudinal characteristics of proton, iron nucleus and gamma induced air showers for different hadronic interaction models. We also show the comparisons of our predictions with those of CORSIKA code.
Lämmerzahl, C; Müller, H; Laemmerzahl, Claus; Macias, Alfredo; Mueller, Holger
2005-01-01
All quantum gravity approaches lead to small modifications in the standard laws of physics which lead to violations of Lorentz invariance. One particular example is the extended standard model (SME). Here, a general phenomenological approach for extensions of the Maxwell equations is presented which turns out to be more general than the SME and which covers charge non--conservation (CNC), too. The new Lorentz invariance violating terms cannot be probed by optical experiments but need, instead, the exploration of the electromagnetic field created by a point charge or a magnetic dipole. Some scalar--tensor theories and higher dimensional brane theories predict CNC in four dimensions and some models violating Special Relativity have been shown to be connected with CNC and its relation to the Einstein Equivalence Principle has been discussed. Due to this upcoming interest, the experimental status of electric charge conservation is reviewed. Up to now there seem to exist no unique tests of charge conservation. CNC...
Teaching Policy Analysis as Research: Consideration and Extension of Options
O'Connor, Mary Katherine; Netting, F. Ellen
2008-01-01
Teaching policy analysis is compared to teaching research skills. Both involve the selection of an appropriate analytical tool to be used with multiple units of analysis; and in both, the selected instrument must fit the purpose of the analysis or the product is not useful. Policy analysis frameworks characteristically address policy process,…
Theoretical analysis of the state of balance in bipedal walking.
Firmani, Flavio; Park, Edward J
2013-04-01
This paper presents a theoretical analysis based on classic mechanical principles of balance of forces in bipedal walking. Theories on the state of balance have been proposed in the area of humanoid robotics and although the laws of classical mechanics are equivalent to both humans and humanoid robots, the resulting motion obtained with these theories is unnatural when compared to normal human gait. Humanoid robots are commonly controlled using the zero moment point (ZMP) with the condition that the ZMP cannot exit the foot-support area. This condition is derived from a physical model in which the biped must always walk under dynamically balanced conditions, making the centre of pressure (CoP) and the ZMP always coincident. On the contrary, humans follow a different strategy characterized by a 'controlled fall' at the end of the swing phase. In this paper, we present a thorough theoretical analysis of the state of balance and show that the ZMP can exit the support area, and its location is representative of the imbalance state characterized by the separation between the ZMP and the CoP. Since humans exhibit this behavior, we also present proof-of-concept results of a single subject walking on an instrumented treadmill at different speeds (from slow 0.7 m/s to fast 2.0 m/s walking with increments of 0.1 m/s) with the motion recorded using an optical motion tracking system. In order to evaluate the experimental results of this model, the coefficient of determination (R2) is used to correlate the measured ground reaction forces and the resultant of inertial and gravitational forces (anteroposterior R² = 0.93, mediolateral R² = 0.89, and vertical R² = 0.86) indicating that there is a high correlation between the measurements. The results suggest that the subject exhibits a complete dynamically balanced gait during slow speeds while experiencing a controlled fall (end of swing phase) with faster speeds. This is quantified with the root-mean-square deviation (RMSD
GRETNA: a graph theoretical network analysis toolbox for imaging connectomics
Directory of Open Access Journals (Sweden)
Jinhui eWang
2015-06-01
Full Text Available Recent studies have suggested that the brain’s structural and functional networks (i.e., connectomics can be constructed by various imaging technologies (e.g., EEG/MEG; structural, diffusion and functional MRI and further characterized by graph theory. Given the huge complexity of network construction, analysis and statistics, toolboxes incorporating these functions are largely lacking. Here, we developed the GRaph thEoreTical Network Analysis (GRETNA toolbox for imaging connectomics. The GRETNA contains several key features as follows: (i an open-source, Matlab-based, cross-platform (Windows and UNIX OS package with a graphical user interface; (ii allowing topological analyses of global and local network properties with parallel computing ability, independent of imaging modality and species; (iii providing flexible manipulations in several key steps during network construction and analysis, which include network node definition, network connectivity processing, network type selection and choice of thresholding procedure; (iv allowing statistical comparisons of global, nodal and connectional network metrics and assessments of relationship between these network metrics and clinical or behavioral variables of interest; and (v including functionality in image preprocessing and network construction based on resting-state functional MRI (R-fMRI data. After applying the GRETNA to a publicly released R-fMRI dataset of 54 healthy young adults, we demonstrated that human brain functional networks exhibit efficient small-world, assortative, hierarchical and modular organizations and possess highly connected hubs and that these findings are robust against different analytical strategies. With these efforts, we anticipate that GRETNA will accelerate imaging connectomics in an easy, quick and flexible manner. GRETNA is freely available on the NITRC website (http://www.nitrc.org/projects/gretna/.
Advances in multiscale theoretical analysis and imaging aspects of turbulence
Shockro, Jennifer
The work presented in this dissertation is focused on two aspects related to turbulent flow. The first of these is the one-dimensional theoretical analysis of the logarithmic spiral in terms of fractal dimension and spectrum. The second is on imaging methodologies and analysis of turbulent jet scalar interfaces in atmospheric conditions, with broad applicability to various studies where turbulence has a key role, such as urban contaminant dispersion or free space laser communications. The logarithmic spiral is of particular interest to studies of turbulence and natural phenomena as it appears frequently in nature with the "Golden Ratio" and is thought to play an important role in turbulent mixing. It is also an inherently anisotropic geometric structure and therefore provides information towards examining phenomena in which anisotropic properties might be expected to appear and is thought to be present as a structure within the fine scales of the turbulent hierarchy. In this work it is subjected to one-dimensional theoretical analysis, focusing on the development of a probability density function (pdf) for the spiral and the relation of the pdf to its fractal dimension. Results indicate that the logarithmic spiral does not have a constant fractal dimension and thus that it does not exhibit any form of self-similar statistical behavior, supporting previous theoretical suppositions about behavior at the fine scales within the turbulent hierarchy. A signal is developed from the pdf in order to evaluate its power spectrum. Results of this analysis provide information about the manner in which energy is carried at different scales of the spiral. To our knowledge, the logarithmic spiral in particular has not yet been examined in this fashion in literature. In order to further investigate this object, the multiscale minima meshless (M(3) ) method isextended and employed computationally to the two-dimensional logarithmic spiral as well as to experimental images of a
A P-value model for theoretical power analysis and its applications in multiple testing procedures
Directory of Open Access Journals (Sweden)
Fengqing Zhang
2016-10-01
Full Text Available Abstract Background Power analysis is a critical aspect of the design of experiments to detect an effect of a given size. When multiple hypotheses are tested simultaneously, multiplicity adjustments to p-values should be taken into account in power analysis. There are a limited number of studies on power analysis in multiple testing procedures. For some methods, the theoretical analysis is difficult and extensive numerical simulations are often needed, while other methods oversimplify the information under the alternative hypothesis. To this end, this paper aims to develop a new statistical model for power analysis in multiple testing procedures. Methods We propose a step-function-based p-value model under the alternative hypothesis, which is simple enough to perform power analysis without simulations, but not too simple to lose the information from the alternative hypothesis. The first step is to transform distributions of different test statistics (e.g., t, chi-square or F to distributions of corresponding p-values. We then use a step function to approximate each of the p-value’s distributions by matching the mean and variance. Lastly, the step-function-based p-value model can be used for theoretical power analysis. Results The proposed model is applied to problems in multiple testing procedures. We first show how the most powerful critical constants can be chosen using the step-function-based p-value model. Our model is then applied to the field of multiple testing procedures to explain the assumption of monotonicity of the critical constants. Lastly, we apply our model to a behavioral weight loss and maintenance study to select the optimal critical constants. Conclusions The proposed model is easy to implement and preserves the information from the alternative hypothesis.
Extensions of positive definite functions applications and their harmonic analysis
Jorgensen, Palle E T; Tian, Feng
2016-01-01
This monograph deals with the mathematics of extending given partial data-sets obtained from experiments; Experimentalists frequently gather spectral data when the observed data is limited, e.g., by the precision of instruments; or by other limiting external factors. Here the limited information is a restriction, and the extensions take the form of full positive definite function on some prescribed group. It is therefore both an art and a science to produce solid conclusions from restricted or limited data. While the theory of is important in many areas of pure and applied mathematics, it is difficult for students and for the novice to the field, to find accessible presentations which cover all relevant points of view, as well as stressing common ideas and interconnections. We have aimed at filling this gap, and we have stressed hands-on-examples.
Dispersion-theoretical analysis of the nucleon electromagnetic form factors
Energy Technology Data Exchange (ETDEWEB)
Belushkin, M.
2007-09-29
The structure of the proton and the neutron is of fundamental importance for the study of the strong interaction dynamics over a wide range of momentum transfers. The nucleon form factors encode information on the internal structure of the nucleon as probed by the electromagnetic interaction, and, to a certain extent, reflect the charge and magnetisation distributions within the proton and the neutron. In this thesis we report on our investigation of the electromagnetic form factors of the proton and the neutron with dispersion relation techniques, including known experimental input on the {pi}{pi}, K anti K and the {rho}{pi} continua and perturbative QCD constraints. We include new experimental data on the pion form factor and the nucleon form factors in our simultaneous analysis of all four form factors in both the space- and the timelike regions for all momentum transfers, and perform Monte- Carlo sampling in order to obtain theoretical uncertainty bands. Finally, we discuss the implications of our results on the pion cloud of the nucleon, the nucleon radii and the Okubo-Zweig-Iizuka rule, and present our results of a model-independent approach to estimating two-photon effects in elastic electron-proton scattering. (orig.)
Dispersion-theoretical analysis of the nucleon electromagnetic form factors
Energy Technology Data Exchange (ETDEWEB)
Belushkin, M.
2007-09-29
The structure of the proton and the neutron is of fundamental importance for the study of the strong interaction dynamics over a wide range of momentum transfers. The nucleon form factors encode information on the internal structure of the nucleon as probed by the electromagnetic interaction, and, to a certain extent, reflect the charge and magnetisation distributions within the proton and the neutron. In this thesis we report on our investigation of the electromagnetic form factors of the proton and the neutron with dispersion relation techniques, including known experimental input on the {pi}{pi}, K anti K and the {rho}{pi} continua and perturbative QCD constraints. We include new experimental data on the pion form factor and the nucleon form factors in our simultaneous analysis of all four form factors in both the space- and the timelike regions for all momentum transfers, and perform Monte- Carlo sampling in order to obtain theoretical uncertainty bands. Finally, we discuss the implications of our results on the pion cloud of the nucleon, the nucleon radii and the Okubo-Zweig-Iizuka rule, and present our results of a model-independent approach to estimating two-photon effects in elastic electron-proton scattering. (orig.)
Theoretical Model and Dynamic Analysis of Soft Yoke Mooring System
Institute of Scientific and Technical Information of China (English)
无
2008-01-01
As a popular solution for mooring an FPSO (Floating Production, Storage and Offloading) permanently in shallow water, the soft yoke mooring system has been widely used in ocean oil production activities in the Bohai Bay of China. In order to simulate the interaction mechanism and conduct dynamic analysis of the soft yoke mooring system, a theoretical model with basic dynamic equations is established. A numerical iteration algorithm based on error estimation is developed to solve the equations and calculate the dynamic response of the mooring system due to FPSO motions. Validation is conducted by wave basin experimentation. It is shown that the numerical simulation takes only a few iteration times and the final errors are small. Furthermore, the calculated results of both the static and dynamic responses agree well with those ones obtained by the model test. It indicates that the efficiency, the precision, the reliability and the validity of the developed numerical algorithm and program are rather good. It is proposed to develop a real-time monitoring system to further monitor the dynamic performance of the FPSO with a soft yoke mooring system under various real sea environments.
Notes on economic time series analysis system theoretic perspectives
Aoki, Masanao
1983-01-01
In seminars and graduate level courses I have had several opportunities to discuss modeling and analysis of time series with economists and economic graduate students during the past several years. These experiences made me aware of a gap between what economic graduate students are taught about vector-valued time series and what is available in recent system literature. Wishing to fill or narrow the gap that I suspect is more widely spread than my personal experiences indicate, I have written these notes to augment and reor ganize materials I have given in these courses and seminars. I have endeavored to present, in as much a self-contained way as practicable, a body of results and techniques in system theory that I judge to be relevant and useful to economists interested in using time series in their research. I have essentially acted as an intermediary and interpreter of system theoretic results and perspectives in time series by filtering out non-essential details, and presenting coherent accounts of wha...
Extension on KOLAS accreditation for chemical analysis of radioactive material
Energy Technology Data Exchange (ETDEWEB)
Sohn, Se Chul; Kim, Y. B.; Kim, W. H. and others
2001-12-01
The research includes the establishment of analytical target for radioactive mateials and analytical procedures fo ran international accreditatin. The determinatin of confidence level of chemical analysis for the uraniu, radium-226, radon-222, and boron was carried out. The instructions for the analysis of radioactive materials were written in this report. As a result of the research, the KOLAS accreditation was extended to the analysis of uranium innatural water, radon-222 or boron in industrial water, and cesium-137 in agricultural products.
A Bivariate Extension to Traditional Empirical Orthogonal Function Analysis
DEFF Research Database (Denmark)
Nielsen, Allan Aasbjerg; Hilger, Klaus Baggesen; Andersen, Ole Baltazar
2002-01-01
This paper describes the application of canonical correlations analysis to the joint analysis of global monthly mean values of 1996-1997 sea surface temperature (SST) and height (SSH) data. The SST data are considered as one set and the SSH data as another set of multivariate observations, both...... as for example an increase in the SST will lead to an increase in the SSH. The analysis clearly shows the build-up of one of the largest El Niño events on record. Also the analysis indicates a phase lag of approximately one month between the SST and SSH fields....
Systems theoretic analysis of the central dogma of molecular biology: some recent results.
Gao, Rui; Yu, Juanyi; Zhang, Mingjun; Tarn, Tzyh-Jong; Li, Jr-Shin
2010-03-01
This paper extends our early study on a mathematical formulation of the central dogma of molecular biology, and focuses discussions on recent insights obtained by employing advanced systems theoretic analysis. The goal of this paper is to mathematically represent and interpret the genetic information flow at the molecular level, and explore the fundamental principle of molecular biology at the system level. Specifically, group theory was employed to interpret concepts and properties of gene mutation, and predict backbone torsion angle along the peptide chain. Finite state machine theory was extensively applied to interpret key concepts and analyze the processes related to DNA hybridization. Using the proposed model, we have transferred the character-based model in molecular biology to a sophisticated mathematical model for calculation and interpretation.
SELECTING LEADERSHIP STYLES PROBLEM IN MANAGEMENT CULTURE: THEORETICAL ANALYSIS
Directory of Open Access Journals (Sweden)
T. N. DUKHINA
2016-01-01
Full Text Available The article carried out a theoretical analysis of the problem of choosing the team leadership styles, which is regarded as the most important component of the control system, due to the content management tasks. At the basis of individual management style management ideologies are implemented in practice through professional management experience as a manager, supervisor used the style or styles of synthesis will depend on the specific situations and managerial abilities. It is proved that the optimum style of management as a set of business and personal qualities of the head is one of the important criteria for successful completion of the collective tasks and the organization as a whole. The estimation of moral and functional components of the formal authority of the head. It is noted that a formal or official authority deterministic set of powers and the rights that assumes his position and that it provides no more than 60% effect on subordinates. Psychological authority consists of the elements of moral and functional authority. The basis of the moral authority of a manager is moral and ideological qualities of the person. Administrative capacity head examined on the basis of three criteria: personal, functional-activity and structure-psychological. There is analysis of the democratic, liberal and authoritarian leadership styles and the conclusion of the discussion of the problem.
Theoretical Analysis of Shrouded Horizontal Axis Wind Turbines
Directory of Open Access Journals (Sweden)
Tariq Abdulsalam Khamlaj
2017-01-01
Full Text Available Numerous analytical studies for power augmentation systems can be found in the literature with the goal to improve the performance of wind turbines by increasing the energy density of the air at the rotor. All methods to date are only concerned with the effects of a diffuser as the power augmentation, and this work extends the semi-empirical shrouded wind turbine model introduced first by Foreman to incorporate a converging-diverging nozzle into the system. The analysis is based on assumptions and approximations of the conservation laws to calculate optimal power coefficients and power extraction, as well as augmentation ratios. It is revealed that the power enhancement is proportional to the mass stream rise produced by the nozzle diffuser-augmented wind turbine (NDAWT. Such mass flow rise can only be accomplished through two essential principles: the increase in the area ratios and/or by reducing the negative back pressure at the exit. The thrust coefficient for optimal power production of a conventional bare wind turbine is known to be 8/9, whereas the theoretical analysis of the NDAWT predicts an ideal thrust coefficient either lower or higher than 8/9 depending on the back pressure coefficient at which the shrouded turbine operates. Computed performance expectations demonstrate a good agreement with numerical and experimental results, and it is demonstrated that much larger power coefficients than for traditional wind turbines are achievable. Lastly, the developed model is very well suited for the preliminary design of a shrouded wind turbine where typically many trade-off studies need to be conducted inexpensively.
Directory of Open Access Journals (Sweden)
Lugovsky V. A.
2016-05-01
Full Text Available The article surveys the process of psychological separation from parents in the student's age. Relevance of the research topic is connected with the existing problems in the modern student environment, which include the general trends of the late maturation in adolescents (infantilization: extension of childhood, low achievement motivation, the lack of desire for selfdevelopment, unwillingness to take responsibility for their own lives. The importance of the theme is emphasized by a number of age problems. Without solving these problems, individual development is almost impossible. The authors give the analysis of the theoretical concepts of separation problems in the domestic and foreign psychology, examine the concept of separation in the context of different approaches to its study. Based on the research, the definition of separation is formulated. Separation individuation processes are discussed in the psychoanalytic direction, through the family system therapy, the study of the level of intergenerational relations in the dichotomy of "proximity - gap", the establishment of the sovereignty of the individual, the formation of psychological space. On the basis of the theoretical analysis the authors categorize the types of separation as contradictory or ambivalent, successful, crisis, conflict categorization and give the characteristics of each type and its impact on the resolution of the separation conflict
De Ridder, E M D; Van Oosterwijck, J O; Vleeming, A; Vanderstraeten, G G; Danneels, L A
2015-04-01
The present study examined the activity levels of the thoracic and lumbar extensor muscles during different extension exercise modalities in healthy individuals. Therefore, 14 subjects performed four different types of extension exercises in prone position: dynamic trunk extension, dynamic-static trunk extension, dynamic leg extension, and dynamic-static leg extension. Pre- and post-exercise muscle functional magnetic resonance imaging scans from the latissimus dorsi, the thoracic and lumbar parts of the longissimus, iliocostalis, and multifidus were performed. Differences in water relaxation values (T2-relaxation) before and after exercise were calculated (T2-shift) as a measure of muscle activity and compared between extension modalities. Linear mixed-model analysis revealed higher lumbar extensor activity during trunk extension compared with leg extension (T2-shift of 5.01 ms and 3.55 ms, respectively) and during the dynamic-static exercise performance compared with the dynamic exercise performance (T2-shift of 4.77 ms and 3.55 ms, respectively). No significant differences in the thoracic extensor activity between the exercises could be demonstrated. During all extension exercises, the latissimus dorsi was the least activated compared with the paraspinal muscles. While all extension exercises are equivalent effective to train the thoracic muscles, trunk extension exercises performed in a dynamic-static way are the most appropriate to enhance lumbar muscle strength.
Extensible Data Set Architecture for Systems Analysis Project
National Aeronautics and Space Administration — The process of aircraft design requires the integration of data from individual analysis of aerodynamic, structural, thermal, and behavioral properties of a flight...
Genetic analysis of presbycusis by arrayed primer extension.
Rodriguez-Paris, Juan; Ballay, Charles; Inserra, Michelle; Stidham, Katrina; Colen, Tahl; Roberson, Joseph; Gardner, Phyllis; Schrijver, Iris
2008-01-01
Using the Hereditary Hearing Loss arrayed primer extension (APEX) array, which contains 198 mutations across 8 hearing loss-associated genes (GJB2, GJB6, GJB3, GJA1, SLC26A4, SLC26A5, 12S-rRNA, and tRNA Ser), we compared the frequency of sequence variants in 94 individuals with early presbycusis to 50 unaffected controls and aimed to identify possible genetic contributors. This cross-sectional study was performed at Stanford University with presbycusis samples from the California Ear Institute. The patients were between ages 20 and 65 yr, with adult-onset sensorineural hearing loss of unknown etiology, and carried a clinical diagnosis of early presbycusis. Exclusion criteria comprised known causes of hearing loss such as significant noise exposure, trauma, ototoxic medication, neoplasm, and congenital infection or syndrome, as well as congenital or pediatric onset. Sequence changes were identified in 11.7% and 10% of presbycusis and control alleles, respectively. Among the presbycusis group, these solely occurred within the GJB2 and SLC26A4 genes. Homozygous and compound heterozygous pathogenic mutations were exclusively seen in affected individuals. We were unable to detect a statistically significant difference between our control and affected populations regarding the frequency of sequence variants detected with the APEX array. Individuals who carry two mild mutations in the GJB2 gene possibly have an increased risk of developing early presbycusis.
ASAP: An Extensible Platform for State Space Analysis
DEFF Research Database (Denmark)
Westergaard, Michael; Evangelista, Sami; Kristensen, Lars Michael
2009-01-01
The ASCoVeCo State space Analysis Platform (ASAP) is a tool for performing explicit state space analysis of coloured Petri nets (CPNs) and other formalisms. ASAP supports a wide range of state space reduction techniques and is intended to be easy to extend and to use, making it a suitable tool...... for students, researchers, and industrial users that would like to analyze protocols and/or experiment with different algorithms. This paper presents ASAP from these two perspectives....
Information- Theoretic Analysis for the Difficulty of Extracting Hidden Information
Institute of Scientific and Technical Information of China (English)
ZHANG Wei-ming; LI Shi-qu; CAO Jia; LIU Jiu-fen
2005-01-01
The difficulty of extracting hidden information,which is essentially a kind of secrecy, is analyzed by information-theoretic method. The relations between key rate, message rate, hiding capacity and difficulty of extraction are studied in the terms of unicity distance of stego-key, and the theoretic conclusion is used to analyze the actual extracting attack on Least Significant Bit(LSB) steganographic algorithms.
The Application and Extension of Backward Software Analysis
Perisic, Aleksandar
2010-01-01
The backward software analysis is a method that emanates from executing a program backwards - instead of taking input data and following the execution path, we start from output data and by executing the program backwards command by command, analyze data that could lead to the current output. The changed perspective forces a developer to think in a new way about the program. It can be applied as a thorough procedure or casual method. With this method, we have many advantages in testing, algorithm and system analysis. For example, in testing the advantage is obvious if the set of output data is smaller than possible inputs. For some programs or algorithms, we know more precisely the output data, so this backward analysis can help in reducing the number of test cases or even in strict verification of an algorithm. The difficulty lies in the fact that we need types of data that no programming language currently supports, so we need additional effort to understand how this method works, or what effort we need to ...
Preliminary analysis of knee stress in Full Extension Landing
Directory of Open Access Journals (Sweden)
Majid Davoodi Makinejad
2013-09-01
Full Text Available OBJECTIVE: This study provides an experimental and finite element analysis of knee-joint structure during extended-knee landing based on the extracted impact force, and it numerically identifies the contact pressure, stress distribution and possibility of bone-to-bone contact when a subject lands from a safe height. METHODS: The impact time and loads were measured via inverse dynamic analysis of free landing without knee flexion from three different heights (25, 50 and 75 cm, using five subjects with an average body mass index of 18.8. Three-dimensional data were developed from computed tomography scans and were reprocessed with modeling software before being imported and analyzed by finite element analysis software. The whole leg was considered to be a fixed middle-hinged structure, while impact loads were applied to the femur in an upward direction. RESULTS: Straight landing exerted an enormous amount of pressure on the knee joint as a result of the body's inability to utilize the lower extremity muscles, thereby maximizing the threat of injury when the load exceeds the height-safety threshold. CONCLUSIONS: The researchers conclude that extended-knee landing results in serious deformation of the meniscus and cartilage and increases the risk of bone-to-bone contact and serious knee injury when the load exceeds the threshold safety height. This risk is considerably greater than the risk of injury associated with walking downhill or flexion landing activities.
Extension of migration velocity analysis to transmitted wavefields
Lameloise, Charles-Antoine; Chauris, Hervé
2016-10-01
Migration velocity analysis aims at automatically updating the large-scale components of the velocity model, called macromodel. Extended Common Image Gathers are panels used to evaluate focusing after imaging and are constructed as a function of a spatial shift introduced in the imaging condition. We investigate how transmitted waves can also be used in migration velocity analysis: instead of back-propagating the residuals associated with reflected waves, we propose to back-propagate the full wavefield. The image function, equivalent to the migrated section for reflected data, does not exhibit localized events in space along horizons but is still sensitive to the choice of the background velocity model and can thus be coupled to the same objective function defined in the image domain. In order to enhance the benefits of direct waves, we consider a cross-well configuration. Direct waves provide a large illumination between two vertical wells. Associated Common Image Gathers present different characteristics than the ones associated with reflected waves in surface acquisition. In particular, energy is spread over up to the maximum penetration depth. We invert cross-well seismic data along two lines. In the first case, the input data contain the full wavefield dominated by transmitted waves. It demonstrates the possibility to handle transmitted waves to determine the velocity model. It appears that the misfit in the data domain is largely reduced after inversion. In the second case, we use the same algorithm, but with reflected observed data only, as in a classical approach. Most of velocity updates are localized around the reflectivity, leading to an incorrect final model. This demonstrates the benefit of transmitted waves for migration velocity analysis in a cross-well configuration.
A quantum information theoretic analysis of three flavor neutrino oscillations
Banerjee, Subhashish; Srikanth, R; Hiesmayr, Beatrix C
2015-01-01
Correlations exhibited by neutrino oscillations are studied via quantum information theoretic quantities. We show that the strongest type of entanglement, genuine multipartite entanglement, is persistent in the flavour changing states. We prove the existence of Bell-type nonlocal features, in both its absolute and genuine avatars. Finally, we show that a measure of nonclassicality, dissension, which is a generalization of quantum discord to the tripartite case, is nonzero for almost the entire range of time in the evolution of an initial electron-neutrino. Via these quantum information theoretic quantities capturing different aspects of quantum correlations, we elucidate the differences between the flavour types, shedding light on the quantum-information theoretic aspects of the weak force.
Theoretical analysis and experimental verification on optical rotational Doppler effect
Zhou, Hailong; Dong, Jianji; Zhang, Pei; Zhang, Xinliang
2016-01-01
We present a theoretical model to sufficiently investigate the optical rotational Doppler effect based on modal expansion method. We find that the frequency shift content is only determined by the surface of spinning object and the reduced Doppler shift is linear to the difference of mode index between input and output orbital angular momentum (OAM) light, and linear to the rotating speed of spinning object as well. An experiment is carried out to verify the theoretical model. We explicitly suggest that the spatial spiral phase distribution of spinning object determines the frequency content. The theoretical model makes us better understand the physical processes of rotational Doppler effect, and thus has many related application fields, such as detection of rotating bodies, imaging of surface and measurement of OAM light.
Theoretical analysis and experimental verification on optical rotational Doppler effect
Zhou, Hailong; Fu, Dongzhi; Dong, Jianji; Zhang, Pei; Zhang, Xinliang
2016-05-01
We present a theoretical model to sufficiently investigate the optical rotational Doppler effect based on modal expansion method. We find that the frequency shift content is only determined by the surface of spinning object and the reduced Doppler shift is linear to the difference of mode index between input and output orbital angular momentum (OAM) light, and linear to the rotating speed of spinning object as well. An experiment is carried out to verify the theoretical model. We explicitly suggest that the spatial spiral phase distribution of spinning object determines the frequency content. The theoretical model makes us better understand the physical processes of rotational Doppler effect, and thus has many related application fields, such as detection of rotating bodies, imaging of surface and measurement of OAM light.
Modelling Opinion Dynamics: Theoretical analysis and continuous approximation
Pinasco, Juan Pablo; Balenzuela, Pablo
2016-01-01
Frequently we revise our first opinions after talking over with other individuals because we get convinced. Argumentation is a verbal and social process aimed at convincing. It includes conversation and persuasion. In this case, the agreement is reached because the new arguments are incorporated. In this paper we deal with a simple model of opinion formation with such persuasion dynamics, and we find the exact analytical solutions for both, long and short range interactions. A novel theoretical approach has been used in order to solve the master equations of the model with non-local kernels. Simulation results demonstrate an excellent agreement with results obtained by the theoretical estimation.
A theoretical analysis of NADPH production and consumption in yeasts
Bruinenberg, P.M.; Van Dijken, J.P.; Scheffers, W.A.
1983-01-01
Theoretical calculations of the NADPH requirement for yeast biomass formation reveal that this parameter is strongly dependent on the carbon and nitrogen source. The data obtained have been used to estimate the carbon flow over the NADPH-producing pathways in these organisms, namely the hexose monop
Theoretical bases analysis of scientific prediction on marketing principles
A.S. Rosohata
2012-01-01
The article presents an overview categorical apparatus of scientific predictions and theoretical foundations results of scientific forecasting. They are integral part of effective management of economic activities. The approaches to the prediction of scientists in different fields of Social science and the categories modification of scientific prediction, based on principles of marketing are proposed.
Advantages and limitations of transition voltage spectroscopy: A theoretical analysis
Mirjani, F.; Thijssen, J.M.; Van der Molen, S.J.
2011-01-01
In molecular charge transport, transition voltage spectroscopy (TVS) holds the promise that molecular energy levels can be explored at bias voltages lower than required for resonant tunneling. We investigate the theoretical basis of this tool using a generic model. In particular, we study the length
Theoretical bases analysis of scientific prediction on marketing principles
Directory of Open Access Journals (Sweden)
A.S. Rosohata
2012-06-01
Full Text Available The article presents an overview categorical apparatus of scientific predictions and theoretical foundations results of scientific forecasting. They are integral part of effective management of economic activities. The approaches to the prediction of scientists in different fields of Social science and the categories modification of scientific prediction, based on principles of marketing are proposed.
The US-China Trade Conflict: A Game Theoretical Analysis
Hebatallah Ghoneim; Yasmine Reda
2008-01-01
Game Theory has been gaining great importance in Economics, encouraging research in many theoretical and applied fields. This paper relies on simple game theory tools to set up a major international trade dispute. Using the backward deduction approach, the strategies of the United States and China in their recent trade conflict are analyzed.
Theoretical Analysis and Derivation of Combustion Wave Parameters
Institute of Scientific and Technical Information of China (English)
CHEN Jun
2006-01-01
Theoretical relations of pressure, density, velocity, temperature and Mach number of combustion waves are built. The parameters' curves with different combustion energy are illustrated in which four zones are pointed out to represent different combustion states. The expressions and curves of parameters are important to analyze the trends of combustion waves, and to determine conditions on which detonation waves or deflagration waves occur.
Metabolome analysis of effect of aspirin on Drosophila lifespan extension.
Song, Chaochun; Zhu, Chenxing; Wu, Qi; Qi, Jiancheng; Gao, Yue; Zhang, Zhichao; Gaur, Uma; Yang, Deying; Fan, Xiaolan; Yang, Mingyao
2017-09-01
Effective approaches for drug development involve the repurposing of existing drugs which are already approved by the FDA. Aspirin has been shown to have many health benefits since its discovery as a nonsteroidal anti-inflammatory drug (NSAID) to treat pain and inflammation. Recent experiments demonstrated the longevity effects of aspirin in Drosophila, but its mechanism remains to be explored. In order to elucidate the effects of drug on metabolism, we carried out the metabolic analysis of aspirin-treated flies. The results identified 404 active metabolites in addition to the extended lifespan and improved healthspan in fly. There were 28 metabolites having significant changes between aspirin-treated group and the control group, out of which 22 compounds were found to have detailed information. These compounds are reported to have important functions in energy metabolism, amino sugar metabolism, and urea metabolism, indicating that aspirin might be playing positive roles in the fly's lifespan and healthspan improvement. Because of the conservation of major longevity pathways and mechanisms in different species, the health benefits of aspirin administration could be extended to other animals and humans as well. Copyright © 2017 Elsevier Inc. All rights reserved.
Mediating Informal Care Online: Findings from an Extensive Requirements Analysis
Directory of Open Access Journals (Sweden)
Christiane Moser
2015-05-01
Full Text Available Organizing and satisfying the increasing demand for social and informal care for older adults is an important topic. We aim at building a peer-to-peer exchange platform that empowers older adults to benefit from receiving support for daily activities and reciprocally offering support to others. In situated interviews and within a survey we investigated the requirements and needs of 246 older adults with mild impairments. Additionally, we conducted an interpretative role analysis of older adults’ collaborative care processes (i.e., support exchange practices in order to identify social roles and understand the inherent expectations towards the execution of support. We will describe our target group in the form of personas and different social roles, as well as user requirements for establishing a successful peer-to-peer collaboration. We also consider our finding from the perspective of social capital theory that allows us to describe in our requirements how relationships provide valuable social resources (i.e., social capital for informal and social care.
Statistical analysis of CSP plants by simulating extensive meteorological series
Pavón, Manuel; Fernández, Carlos M.; Silva, Manuel; Moreno, Sara; Guisado, María V.; Bernardos, Ana
2017-06-01
The feasibility analysis of any power plant project needs the estimation of the amount of energy it will be able to deliver to the grid during its lifetime. To achieve this, its feasibility study requires a precise knowledge of the solar resource over a long term period. In Concentrating Solar Power projects (CSP), financing institutions typically requires several statistical probability of exceedance scenarios of the expected electric energy output. Currently, the industry assumes a correlation between probabilities of exceedance of annual Direct Normal Irradiance (DNI) and energy yield. In this work, this assumption is tested by the simulation of the energy yield of CSP plants using as input a 34-year series of measured meteorological parameters and solar irradiance. The results of this work show that, even if some correspondence between the probabilities of exceedance of annual DNI values and energy yields is found, the intra-annual distribution of DNI may significantly affect this correlation. This result highlights the need of standardized procedures for the elaboration of representative DNI time series representative of a given probability of exceedance of annual DNI.
Self-selection into teamwork: A theoretical and experimental analysis
Stribeck, Agnes; Pull, Kerstin
2010-01-01
We analyze self-selection decisions regarding teamwork both theoretically and empirically. While we focus on individual talent, we also investigate the effects of team tasks, individual teamwork skills, and expectations concerning the talent and teamwork skills of potential teammates as further determinants in the self-selection process. Putting our hypotheses derived from a basic self-selection model in dialogue with original data from a real-task laboratory experiment, we are able to show t...
Theoretical analysis of radiation-balanced double clad fiber laser
Institute of Scientific and Technical Information of China (English)
CHEN Ji-xin; SUI Zhan; CHEN Fu-shen; LI Ming-zhong; WANG Jian-jun
2005-01-01
In this letter,a theoretical model of radiation-balanced double clad fiber laser is presented.The characteristic of the laser with Yb doped double clad fiber is analyzed numerically.It is concluded that high output laser power can be obtained by selecting output coupling mirror with lower reflectivity,improving Yb doped concentration and choosing fiber length. This result can help us to design radiation balanced fiber laser.
Microgenetic Analysis of Moral Development: Theoretical and Methodological Issues
Barrios, Alia; Barbato,Silviane; Branco,Angela
2012-01-01
New ideas and methodologies need to be developed to advance our knowledge in the understanding of moral development. The intertwined nature of human activities, communication processes, and the numerous aspects of morality pose a challenge to researchers to construct a methodology that takes into account cognition, affect, sociocultural processes and characteristics, as well as the active role of individuals in their own development. In this paper we aim at suggesting fresh theoretical ideas ...
Multivariate and 2D Extensions of Singular Spectrum Analysis with the Rssa Package
Directory of Open Access Journals (Sweden)
Nina Golyandina
2015-10-01
Full Text Available Implementation of multivariate and 2D extensions of singular spectrum analysis (SSA by means of the R package Rssa is considered. The extensions include MSSA for simultaneous analysis and forecasting of several time series and 2D-SSA for analysis of digital images. A new extension of 2D-SSA analysis called shaped 2D-SSA is introduced for analysis of images of arbitrary shape, not necessary rectangular. It is shown that implementation of shaped 2D-SSA can serve as a basis for implementation of MSSA and other generalizations. Efficient implementation of operations with Hankel and Hankel-block-Hankel matrices through the fast Fourier transform is suggested. Examples with code fragments in R, which explain the methodology and demonstrate the proper use of Rssa, are presented.
Analysis of Theoretical Basis of Direct Subsidies for Grain Production
Institute of Scientific and Technical Information of China (English)
Shengping; SHI; Xiaorong; LUO; Hongjing; LI
2014-01-01
Financial distribution to compensate grain production reflects governmental macro-control on grain production and supply. With the reference of agricultural basic theory,agricultural multi-function theory,economic externality theory,public finance and other theories,this article points out that direct subsidies for grain production is reasonable and necessary with six main theoretical basis,namely fundamentality,multi-function,positive externality of grain production,particularity of grain supply and demand,grain safety being closely linked with national security and basic function of service-oriented government.
Information-theoretic analysis of electronic and printed document authentication
Voloshynovskiy, Sviatoslav; Koval, Oleksiy; Villan, Renato; Topak, Emre; Vila Forcén, José Emilio; Deguillaume, Frederic; Rytsar, Yuriy; Pun, Thierry
2006-02-01
In this paper we consider the problem of document authentication in electronic and printed forms. We formulate this problem from the information-theoretic perspectives and present the joint source-channel coding theorems showing the performance limits in such protocols. We analyze the security of document authentication methods and present the optimal attacking strategies with corresponding complexity estimates that, contrarily to the existing studies, crucially rely on the information leaked by the authentication protocol. Finally, we present the results of experimental validation of the developed concept that justifies the practical efficiency of the elaborated framework.
A theoretical analysis of global characteristics of spread-F
Institute of Scientific and Technical Information of China (English)
无
2001-01-01
Spread-F is an important ionosphere pheonome non and it has much effect on radio wave propogation. Tak ing magnetic inclination and declination into consideration, a theoretical model is deduced for the linear growth-rate of spread-F. It is a generalization of the earlier equatorial model and a relatively complete description o f the spread-F pheonomenon. This theory shows that the magnetic configu ration, i.e. the magnetic strength, inclination and declination,affects the occurrence rate greatly, which forms some re gional distribution characteristics of the spread-F.
A game-theoretic perspective on rough set analysis
Institute of Scientific and Technical Information of China (English)
YAO Jing-tao; HERBERT Joseph P
2008-01-01
Determining the correct threshold values for the probabilistic rough set approaches has been a heated issue among the community. Existing techniques offer no way in guaranteeing that the calculated values optimize the classification ability of the decision rules derived from this configuration. This article will formulate a game theoretic approach to calculating these thresholds to ensure correct approximation region size. Using payoff tables created from approximation measures and modified conditional risk strategies, we provide the user with tolerance levels for their loss functions. Using the tolerance values, new thresholds are calculated to provide correct classification regions. This will aid in determining a set of optimal region threshold values for decision making.
Theoretical Analysis of Magnetorheological Damper Characteristics in Squeeze Mode
Directory of Open Access Journals (Sweden)
Sapiński Bogdan
2015-06-01
Full Text Available The paper summarises the theoretical study of a magnetorheological (MR damper operated in squeeze mode, intended to be used as an actuator in a semi-active mount system in a car motor. The structural design and operating principle of the damper are described and a simplified model of the MR fluid flow in the gap is presented. The plots of the damper force generated by the MR damper are obtained for monoharmonic piston motion with respect to the centre point of the gap height and in the conditions of the control coil being supplied with direct current.
Sparsity analysis of DS spread spectrum signals via theoretical analysis and dictionary learning
Wang, Kai; Wu, Bin; Wang, Bo
2017-04-01
For the purpose of solving the problem of high sampling rate and massive data processing brought by high bandwidth in the field of Aerospace Communication, researchers applied CS theory to spread spectrum signal processing. Sparsity analysis is the prerequisite for the application of CS theory. This paper studies the sparsity of the DS spread spectrum signals, which is the most common kind of signal in the current TT&C systems. Based on the theoretical analysis we get the sparse dictionary, then the dictionary is optimized by K-SVD dictionary learning algorithm. The simulation results show that the two signals have strong sparsity in the constructed sparse base dictionary, which lays a theoretical foundation for the TT&C spread spectrum signal processing based on CS theory.
Energy Technology Data Exchange (ETDEWEB)
Thomas, John (Massachusetts Institute of Technology)
2012-05-01
Systems Theoretic Process Analysis (STPA) is a powerful new hazard analysis method designed to go beyond traditional safety techniques - such as Fault Tree Analysis (FTA) - that overlook important causes of accidents like flawed requirements, dysfunctional component interactions, and software errors. While proving to be very effective on real systems, no formal structure has been defined for STPA and its application has been ad-hoc with no rigorous procedures or model-based design tools. This report defines a formal mathematical structure underlying STPA and describes a procedure for systematically performing an STPA analysis based on that structure. A method for using the results of the hazard analysis to generate formal safety-critical, model-based system and software requirements is also presented. Techniques to automate both the analysis and the requirements generation are introduced, as well as a method to detect conflicts between the safety and other functional model-based requirements during early development of the system.
Anion order in perovskites: a group-theoretical analysis.
Talanov, M V; Shirokov, V B; Talanov, V M
2016-03-01
Anion ordering in the structure of cubic perovskite has been investigated by the group-theoretical method. The possibility of the existence of 261 ordered low-symmetry structures, each with a unique space-group symmetry, is established. These results include five binary and 14 ternary anion superstructures. The 261 idealized anion-ordered perovskite structures are considered as aristotypes, giving rise to different derivatives. The structures of these derivatives are formed by tilting of BO6 octahedra, distortions caused by the cooperative Jahn-Teller effect and other physical effects. Some derivatives of aristotypes exist as real substances, and some as virtual ones. A classification of aristotypes of anion superstructures in perovskite is proposed: the AX class (the simultaneous ordering of A cations and anions in cubic perovskite structure), the BX class (the simultaneous ordering of B cations and anions) and the X class (the ordering of anions only in cubic perovskite structure). In most perovskites anion ordering is accompanied by cation ordering. Therefore, the main classes of anion order in perovskites are the AX and BX classes. The calculated structures of some anion superstructures are reported. Comparison of predictions and experimentally investigated anion superstructures shows coherency of theoretical and experimental results.
Task Analysis in Instructional Program Development. Theoretical Paper No. 52.
Bernard, Michael E.
A review of task analysis procedures beginning with the military training and systems development approach and covering the more recent work of Gagne, Klausmeier, Merrill, Resnick, and others is presented along with a plan for effective instruction based on the review of task analysis. Literature dealing with the use of task analysis in programmed…
Image Segmentation and Analysis of Flexion-Extension Radiographs of Cervical Spines
Eniko T. Enikov; Rein Anton
2014-01-01
We present a new analysis tool for cervical flexion-extension radiographs based on machine vision and computerized image processing. The method is based on semiautomatic image segmentation leading to detection of common landmarks such as the spinolaminar (SL) line or contour lines of the implanted anterior cervical plates. The technique allows for visualization of the local curvature of these landmarks during flexion-extension experiments. In addition to changes in the curvature of the SL lin...
Non-extensive analysis of seismicity: application to some seismic sequences of Morocco
Telesca, Luciano; Rouai, Mohamed
2011-01-01
The magnitude distribution of three seismic sequences occurred in Morocco were investigated by means of the Tsallis-based non-extensive analysis. The non-extensive parameters were estimated by means of the Levenberg-Marquadt nonlinear least square fitting method. It was found that the q value could be a good indicator of the complexity of seismic phenomena. Such findings could contribute in better understanding the dynamics of seismicity and suggesting a unifying view of earthquake occurrence.
The creep experiment and theoretical model analysis of gascontaining coal
Institute of Scientific and Technical Information of China (English)
YIN Guang-zhi; ZHANG Dong-ming; WANG Wei-zhong
2007-01-01
A creep experiment of preformed molding coal under different confining pressures were carried out using self-developed 3-triaxial creep loading device for gas-containing coal, which loaded by Shimadzu AGI-250 kN electrical servo-controlled stiffness testing machine. Based on the experimental results, the variation trend of axial deformation under different stress states was studied, and creep failure characteristics of gascontaining coal under different confining pressures were analyzed. The experimental results were identified with seven-component nonlinear viscoelasto-plastic creep model (Hohai model), and the creep material parameters were obtained. The experimental result complies well with the theoretical value of this model. It indicates that creep constitutive relation of gas-containing coal can be expressed by nonlinear viscoelasto-plastic creep model correctly.
Income Distribution Dependence of Poverty Measure: A Theoretical Analysis
Chattopadhyay, A K; Chattopadhyay, Amit K; Mallick, Sushanta K
2005-01-01
With a new deprivation (or poverty) function, in this paper, we theoretically study the changes in poverty with respect to the `global' mean and variance of the income distribution using Indian survey data. We show that when the income obeys a log-normal distribution, a rising mean income generally indicates a reduction in poverty while an increase in the variance of the income distribution increases poverty. This altruistic view for a developing economy, however, is not tenable anymore once the poverty index is found to follow a pareto distribution. Here although a rising mean income indicates a reduction in poverty, due to the presence of an inflexion point in the poverty function, there is a critical value of the variance below which poverty decreases with increasing variance while beyond this value, poverty undergoes a steep increase followed by a decrease with respect to higher variance. Following these results, we make quantitative predictions to correlate a developing with a developed economy.
An Information Theoretic Analysis of Decision in Computer Chess
Godescu, Alexandru
2011-01-01
The basis of the method proposed in this article is the idea that information is one of the most important factors in strategic decisions, including decisions in computer chess and other strategy games. The model proposed in this article and the algorithm described are based on the idea of a information theoretic basis of decision in strategy games . The model generalizes and provides a mathematical justification for one of the most popular search algorithms used in leading computer chess programs, the fractional ply scheme. However, despite its success in leading computer chess applications, until now few has been published about this method. The article creates a fundamental basis for this method in the axioms of information theory, then derives the principles used in programming the search and describes mathematically the form of the coefficients. One of the most important parameters of the fractional ply search is derived from fundamental principles. Until now this coefficient has been usually handcrafted...
Theoretical and software considerations for nonlinear dynamic analysis
Schmidt, R. J.; Dodds, R. H., Jr.
1983-01-01
In the finite element method for structural analysis, it is generally necessary to discretize the structural model into a very large number of elements to accurately evaluate displacements, strains, and stresses. As the complexity of the model increases, the number of degrees of freedom can easily exceed the capacity of present-day software system. Improvements of structural analysis software including more efficient use of existing hardware and improved structural modeling techniques are discussed. One modeling technique that is used successfully in static linear and nonlinear analysis is multilevel substructuring. This research extends the use of multilevel substructure modeling to include dynamic analysis and defines the requirements for a general purpose software system capable of efficient nonlinear dynamic analysis. The multilevel substructuring technique is presented, the analytical formulations and computational procedures for dynamic analysis and nonlinear mechanics are reviewed, and an approach to the design and implementation of a general purpose structural software system is presented.
Theoretical analysis of single molecule spectroscopy lineshapes of conjugated polymers
Devi, Murali
Conjugated Polymers(CPs) exhibit a wide range of highly tunable optical properties. Quantitative and detailed understanding of the nature of excitons responsible for such a rich optical behavior has significant implications for better utilization of CPs for more efficient plastic solar cells and other novel optoelectronic devices. In general, samples of CPs are plagued with substantial inhomogeneous broadening due to various sources of disorder. Single molecule emission spectroscopy (SMES) offers a unique opportunity to investigate the energetics and dynamics of excitons and their interactions with phonon modes. The major subject of the present thesis is to analyze and understand room temperature SMES lineshapes for a particular CP, called poly(2,5-di-(2'-ethylhexyloxy)-1,4-phenylenevinylene) (DEH-PPV). A minimal quantum mechanical model of a two-level system coupled to a Brownian oscillator bath is utilized. The main objective is to identify the set of model parameters best fitting a SMES lineshape for each of about 200 samples of DEH-PPV, from which new insight into the nature of exciton-bath coupling can be gained. This project also entails developing a reliable computational methodology for quantum mechanical modeling of spectral lineshapes in general. Well-known optimization techniques such as gradient descent, genetic algorithms, and heuristic searches have been tested, employing an L2 measure between theoretical and experimental lineshapes for guiding the optimization. However, all of these tend to result in theoretical lineshapes qualitatively different from experimental ones. This is attributed to the ruggedness of the parameter space and inadequateness of the L2 measure. On the other hand, when the dynamic reduction of the original parameter space to a 2-parameter space through feature searching and visualization of the search space paths using directed acyclic graphs(DAGs), the qualitative nature of the fitting improved significantly. For a more
Image Segmentation and Analysis of Flexion-Extension Radiographs of Cervical Spines
Directory of Open Access Journals (Sweden)
Eniko T. Enikov
2014-01-01
Full Text Available We present a new analysis tool for cervical flexion-extension radiographs based on machine vision and computerized image processing. The method is based on semiautomatic image segmentation leading to detection of common landmarks such as the spinolaminar (SL line or contour lines of the implanted anterior cervical plates. The technique allows for visualization of the local curvature of these landmarks during flexion-extension experiments. In addition to changes in the curvature of the SL line, it has been found that the cervical plates also deform during flexion-extension examination. While extension radiographs reveal larger curvature changes in the SL line, flexion radiographs on the other hand tend to generate larger curvature changes in the implanted cervical plates. Furthermore, while some lordosis is always present in the cervical plates by design, it actually decreases during extension and increases during flexion. Possible causes of this unexpected finding are also discussed. The described analysis may lead to a more precise interpretation of flexion-extension radiographs, allowing diagnosis of spinal instability and/or pseudoarthrosis in already seemingly fused spines.
Graph theoretical analysis of EEG functional connectivity during music perception.
Wu, Junjie; Zhang, Junsong; Liu, Chu; Liu, Dongwei; Ding, Xiaojun; Zhou, Changle
2012-11-05
The present study evaluated the effect of music on large-scale structure of functional brain networks using graph theoretical concepts. While most studies on music perception used Western music as an acoustic stimulus, Guqin music, representative of Eastern music, was selected for this experiment to increase our knowledge of music perception. Electroencephalography (EEG) was recorded from non-musician volunteers in three conditions: Guqin music, noise and silence backgrounds. Phase coherence was calculated in the alpha band and between all pairs of EEG channels to construct correlation matrices. Each resulting matrix was converted into a weighted graph using a threshold, and two network measures: the clustering coefficient and characteristic path length were calculated. Music perception was found to display a higher level mean phase coherence. Over the whole range of thresholds, the clustering coefficient was larger while listening to music, whereas the path length was smaller. Networks in music background still had a shorter characteristic path length even after the correction for differences in mean synchronization level among background conditions. This topological change indicated a more optimal structure under music perception. Thus, prominent small-world properties are confirmed in functional brain networks. Furthermore, music perception shows an increase of functional connectivity and an enhancement of small-world network organizations.
Theoretical analysis of high-resolution digital mammography.
Suryanarayanan, Sankararaman; Karellas, Andrew; Vedantham, Srinivasan; Sechopoulos, Ioannis
2006-06-21
The performance of a high-resolution charge coupled device-based full-field digital mammography imager was analysed using a mathematical framework based on an adaptation of cascaded linear systems theory described by other investigators. This work has been conducted in order to understand the impact of various design parameters on the physical performance characteristics of the imager. Specifically, the effect of pixel size, scintillator thickness and packing density, x-ray spectra, air kerma, dark current, charge integration time, and pixel fill-factor on the frequency dependent detective quantum efficiency was studied using a charge-coupled device as a reference platform. The imaging system was modelled as a series of physical processes with gain and spatial spreading. For each stage, the signal and noise power spectra were computed and propagated through the imaging chain as inputs to subsequent stages. Good agreement between experimental and theoretical predictions was obtained for various x-ray spectral conditions that were investigated. The modulation transfer function, MTF(f) and detective quantum efficiency DQE(f) characteristics obtained in this study are encouraging and comparable to other digital mammography systems. The results of this study strongly suggest the feasibility of large area scintillator-based digital mammography imagers with pixel sizes below 100 microm.
THEORETICAL ANALYSIS OF THE STABILITY OF A DEEP ROADWAY
Institute of Scientific and Technical Information of China (English)
付国彬
1995-01-01
In this paper the thickness of a broken zone, a state parameter of roadway surrounding rock, is used as the index to evaluate the stability of surrounding rock of a deep roadway. The paper gives a theoretic formula for calculating the thickness of the broken zone. The author points out that not only the ultimate strength of rockmass but its residual strength and strain-softening level all have a great influence on the stability of surrounding rock of a deep roadway. The peper′s results show that to reinforce surrounding rock, raise its residual strength and lower its strain-softening level should be taken as a basic requirement for supports of a deep roadway. In addition, the research also indicates that it is impossible for roadway supports to change surrounding rock states of a deep roadway, so it is certain for them to work in a broken state. For this reason, a sufficient yieldable quantity is necessary for roadway supports used in deep mining.
Theoretical limits on detection and analysis of small earthquakes
Kwiatek, Grzegorz; Ben-Zion, Yehuda
2016-08-01
We investigate theoretical limits on detection and reliable estimates of source characteristics of small earthquakes using synthetic seismograms for shear/tensile dislocations on kinematic circular ruptures and observed seismic noise and properties of several acquisition systems (instrument response, sampling rate). Simulated source time functions for shear/tensile dislocation events with different magnitudes, static stress drops, and rupture velocities provide estimates for the amplitude and frequency content of P and S phases at various observation angles. The source time functions are convolved with a Green's function for a homogenous solid assuming given P, S wave velocities and attenuation coefficients and a given instrument response. The synthetic waveforms are superposed with average levels of the observed ambient seismic noise up to 1 kHz. The combined seismograms are used to calculate signal-to-noise ratios and expected frequency content of P and S phases at various locations. The synthetic simulations of signal-to-noise ratio reproduce observed ratios extracted from several well-recorded data sets. The results provide guidelines on detection of small events in various geological environments, along with information relevant to reliable analyses of earthquake source properties.
Income distribution dependence of poverty measure: A theoretical analysis
Chattopadhyay, Amit K.; Mallick, Sushanta K.
2007-04-01
Using a modified deprivation (or poverty) function, in this paper, we theoretically study the changes in poverty with respect to the ‘global’ mean and variance of the income distribution using Indian survey data. We show that when the income obeys a log-normal distribution, a rising mean income generally indicates a reduction in poverty while an increase in the variance of the income distribution increases poverty. This altruistic view for a developing economy, however, is not tenable anymore once the poverty index is found to follow a pareto distribution. Here although a rising mean income indicates a reduction in poverty, due to the presence of an inflexion point in the poverty function, there is a critical value of the variance below which poverty decreases with increasing variance while beyond this value, poverty undergoes a steep increase followed by a decrease with respect to higher variance. Identifying this inflexion point as the poverty line, we show that the pareto poverty function satisfies all three standard axioms of a poverty index [N.C. Kakwani, Econometrica 43 (1980) 437; A.K. Sen, Econometrica 44 (1976) 219] whereas the log-normal distribution falls short of this requisite. Following these results, we make quantitative predictions to correlate a developing with a developed economy.
Fuzzy set theoretic approach to fault tree analysis
African Journals Online (AJOL)
user
Research in conventional fault tree analysis (FTA) is based mainly on failure ... Thus for a very complex system having large number of components, the ..... Smaller, the triangular fuzzy number B-Ai, will result in the best approximation for B.
Category theoretic analysis of hierarchical protein materials and social networks
Spivak, David I; Buehler, Markus J
2011-01-01
Materials in biology span all the scales from Angstroms to meters and typically consist of complex hierarchical assemblies of simple building blocks. Here we review an application of category theory to describe structural and resulting functional properties of biological protein materials by developing so-called ologs. An olog is like a "concept web" or "semantic network" except that it follows a rigorous mathematical formulation based on category theory. This key difference ensures that an olog is unambiguous, highly adaptable to evolution and change, and suitable for sharing concepts with other ologs. We consider a simple example of an alpha-helical and an amyloid-like protein filament subjected to axial extension and develop an olog representation of their structural and resulting mechanical properties. We also construct a representation of a social network in which people send text-messages to their nearest neighbors and act as a team to perform a task. We show that the olog for the protein and the olog f...
Theoretical and methodological analysis of personality theories of leadership
Directory of Open Access Journals (Sweden)
Оксана Григорівна Гуменюк
2016-10-01
Full Text Available The psychological analysis of personality theories of leadership, which is the basis for other conceptual approaches to understanding the nature of leadership, is conducted. Conceptual approach of leadership is analyzed taking into account the priority of personality theories, including: heroic, psychoanalytic, «trait» theory, charismatic and five-factor. It is noted that the psychological analysis of personality theories are important in understanding the nature of leadership
Parametric sensitivity analysis for stochastic molecular systems using information theoretic metrics
Energy Technology Data Exchange (ETDEWEB)
Tsourtis, Anastasios, E-mail: tsourtis@uoc.gr [Department of Mathematics and Applied Mathematics, University of Crete, Crete (Greece); Pantazis, Yannis, E-mail: pantazis@math.umass.edu; Katsoulakis, Markos A., E-mail: markos@math.umass.edu [Department of Mathematics and Statistics, University of Massachusetts, Amherst, Massachusetts 01003 (United States); Harmandaris, Vagelis, E-mail: harman@uoc.gr [Department of Mathematics and Applied Mathematics, University of Crete, and Institute of Applied and Computational Mathematics (IACM), Foundation for Research and Technology Hellas (FORTH), GR-70013 Heraklion, Crete (Greece)
2015-07-07
In this paper, we present a parametric sensitivity analysis (SA) methodology for continuous time and continuous space Markov processes represented by stochastic differential equations. Particularly, we focus on stochastic molecular dynamics as described by the Langevin equation. The utilized SA method is based on the computation of the information-theoretic (and thermodynamic) quantity of relative entropy rate (RER) and the associated Fisher information matrix (FIM) between path distributions, and it is an extension of the work proposed by Y. Pantazis and M. A. Katsoulakis [J. Chem. Phys. 138, 054115 (2013)]. A major advantage of the pathwise SA method is that both RER and pathwise FIM depend only on averages of the force field; therefore, they are tractable and computable as ergodic averages from a single run of the molecular dynamics simulation both in equilibrium and in non-equilibrium steady state regimes. We validate the performance of the extended SA method to two different molecular stochastic systems, a standard Lennard-Jones fluid and an all-atom methane liquid, and compare the obtained parameter sensitivities with parameter sensitivities on three popular and well-studied observable functions, namely, the radial distribution function, the mean squared displacement, and the pressure. Results show that the RER-based sensitivities are highly correlated with the observable-based sensitivities.
Graph theoretical analysis of resting magnetoencephalographic functional connectivity networks
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Lindsay eRutter
2013-07-01
Full Text Available Complex networks have been observed to comprise small-world properties, believed to represent an optimal organization of local specialization and global integration of information processing at reduced wiring cost. Here, we applied magnitude squared coherence to resting magnetoencephalographic time series in reconstructed source space, acquired from controls and patients with schizophrenia, and generated frequency-dependent adjacency matrices modeling functional connectivity between virtual channels. After configuring undirected binary and weighted graphs, we found that all human networks demonstrated highly localized clustering and short characteristic path lengths. The most conservatively thresholded networks showed efficient wiring, with topographical distance between connected vertices amounting to one-third as observed in surrogate randomized topologies. Nodal degrees of the human networks conformed to a heavy-tailed exponentially truncated power-law, compatible with the existence of hubs, which included theta and alpha bilateral cerebellar tonsil, beta and gamma bilateral posterior cingulate, and bilateral thalamus across all frequencies. We conclude that all networks showed small-worldness, minimal physical connection distance, and skewed degree distributions characteristic of physically-embedded networks, and that these calculations derived from graph theoretical mathematics did not quantifiably distinguish between subject populations, independent of bandwidth. However, post-hoc measurements of edge computations at the scale of the individual vertex revealed trends of reduced gamma connectivity across the posterior medial parietal cortex in patients, an observation consistent with our prior resting activation study that found significant reduction of synthetic aperture magnetometry gamma power across similar regions. The basis of these small differences remains unclear.
Accuracy Analysis of a Box-wing Theoretical SRP Model
Wang, Xiaoya; Hu, Xiaogong; Zhao, Qunhe; Guo, Rui
2016-07-01
For Beidou satellite navigation system (BDS) a high accuracy SRP model is necessary for high precise applications especially with Global BDS establishment in future. The BDS accuracy for broadcast ephemeris need be improved. So, a box-wing theoretical SRP model with fine structure and adding conical shadow factor of earth and moon were established. We verified this SRP model by the GPS Block IIF satellites. The calculation was done with the data of PRN 1, 24, 25, 27 satellites. The results show that the physical SRP model for POD and forecast for GPS IIF satellite has higher accuracy with respect to Bern empirical model. The 3D-RMS of orbit is about 20 centimeters. The POD accuracy for both models is similar but the prediction accuracy with the physical SRP model is more than doubled. We tested 1-day 3-day and 7-day orbit prediction. The longer is the prediction arc length, the more significant is the improvement. The orbit prediction accuracy with the physical SRP model for 1-day, 3-day and 7-day arc length are 0.4m, 2.0m, 10.0m respectively. But they are 0.9m, 5.5m and 30m with Bern empirical model respectively. We apply this means to the BDS and give out a SRP model for Beidou satellites. Then we test and verify the model with Beidou data of one month only for test. Initial results show the model is good but needs more data for verification and improvement. The orbit residual RMS is similar to that with our empirical force model which only estimate the force for along track, across track direction and y-bias. But the orbit overlap and SLR observation evaluation show some improvement. The remaining empirical force is reduced significantly for present Beidou constellation.
Theoretical performance analysis for CMOS based high resolution detectors.
Jain, Amit; Bednarek, Daniel R; Rudin, Stephen
2013-03-06
High resolution imaging capabilities are essential for accurately guiding successful endovascular interventional procedures. Present x-ray imaging detectors are not always adequate due to their inherent limitations. The newly-developed high-resolution micro-angiographic fluoroscope (MAF-CCD) detector has demonstrated excellent clinical image quality; however, further improvement in performance and physical design may be possible using CMOS sensors. We have thus calculated the theoretical performance of two proposed CMOS detectors which may be used as a successor to the MAF. The proposed detectors have a 300 μm thick HL-type CsI phosphor, a 50 μm-pixel CMOS sensor with and without a variable gain light image intensifier (LII), and are designated MAF-CMOS-LII and MAF-CMOS, respectively. For the performance evaluation, linear cascade modeling was used. The detector imaging chains were divided into individual stages characterized by one of the basic processes (quantum gain, binomial selection, stochastic and deterministic blurring, additive noise). Ranges of readout noise and exposure were used to calculate the detectors' MTF and DQE. The MAF-CMOS showed slightly better MTF than the MAF-CMOS-LII, but the MAF-CMOS-LII showed far better DQE, especially for lower exposures. The proposed detectors can have improved MTF and DQE compared with the present high resolution MAF detector. The performance of the MAF-CMOS is excellent for the angiography exposure range; however it is limited at fluoroscopic levels due to additive instrumentation noise. The MAF-CMOS-LII, having the advantage of the variable LII gain, can overcome the noise limitation and hence may perform exceptionally for the full range of required exposures; however, it is more complex and hence more expensive.
Theoretical performance analysis of multislice channelized Hotelling observers
Goossens, Bart; Platiša, Ljiljana; Philips, Wilfried
2012-02-01
Quality assessment of 3D medical images is becoming increasingly important, because of clinical practice rapidly moving in the direction of volumetric imaging. In a recent publication, three multi-slice channelized Hotelling observer (msCHO) models are presented for the task of detecting 3D signals in multi-slice images, where each multi-slice image is inspected in a so called stack-browsing mode. The observer models are based on the assumption that humans observe multi-slice images in a simple two stage process, and each of the models implement this principle in a different way. In this paper, we investigate the theoretical performance, in terms of detection signal-to-noise-ratio (SNR) of msCHO models, for the task of detecting a separable signal in a Gaussian background with separable covariance matrix. We find that, despite the differences in architecture of the three models, they all have the same asymptotical performance in this task (i.e., when the number of training images tends to infinity). On the other hand, when backgrounds with nonseparable covariance matrices are considered, the third model, msCHOc, is expected to perform slightly better than the other msCHO models (msCHOa and msCHOb), but only when sufficient training images are provided. These findings suggest that the choice between the msCHO models mainly depends on the experiment setup (e.g., the number of available training samples), while the relation to human observers depends on the particular choice of the "temporal" channels that the msCHO models use.
1979-01-01
Contractor information requirements necessary to support the power extension package project of the space shuttle program are specified for the following categories of data: project management; configuration management; systems engineering and test; manufacturing; reliability, quality assurance and safety; logistics; training; and operations.
1979-01-01
The functional, performance, design, and test requirements for the Orbiter power extension package and its associated ground support equipment are defined. Both government and nongovernment standards and specifications are cited for the following subsystems: electrical power, structural/mechanical, avionics, and thermal control. Quality control assurance provisions and preparation for delivery are also discussed.
1979-01-01
This specification establishes the natural and induced environments to which the power extension package may be exposed during ground operations and space operations with the shuttle system. Space induced environments are applicable at the Orbiter attach point interface location. All probable environments are systematically listed according to each ground and mission phase.
Gender bias in primary education a theoretical analysis
Directory of Open Access Journals (Sweden)
Róbert Osaďan
2013-11-01
Full Text Available For decades, gender bias and inequity have remained extensive issues in nearly all societies in the world. During the past years, the effects of these issues have extended to one of the most important facets in our society - the education sector. Although this may not be immediately shocking, a lot of researchers as well as concerned educators and parents believe otherwise. As a matter of fact, a myriad of studies and research projects have already proven that gender discrimination, bias, and other related issues in sexuality actually exist in most primary schools throughout the globe. These literary materials present vital points that provide the initiative for primary school educators, school administrators, and other parents to become aware of the gender issues, which significantly affect the school performance and achievement of the concerned students, most of them being girls. Also, a number of studies have identified gender bias agents and their contributions in the worsening of the problem. Obviously, this problem needs to be addressed by the people most empowered - the educators. There is no question whether or not primary school teachers possess the knowledge to circumvent this bias inside their classrooms. The true concern is when they will actually start to apply crucial measures to resolve and get rid of gender bias. Once they eliminate their own prejudices about their students in terms of gender- related issues, they will be able to provide each of their pupils the right and proper education that the children deserve to get. And if all students obtain fair educational treatment, academic excellence and competence will merely be two of the countless benefits they can get.
Handbook of Time Series Analysis Recent Theoretical Developments and Applications
Schelter, Björn; Timmer, Jens
2006-01-01
This handbook provides an up-to-date survey of current research topics and applications of time series analysis methods written by leading experts in their fields. It covers recent developments in univariate as well as bivariate and multivariate time series analysis techniques ranging from physics' to life sciences' applications. Each chapter comprises both methodological aspects and applications to real world complex systems, such as the human brain or Earth's climate. Covering an exceptionally broad spectrum of topics, beginners, experts and practitioners who seek to understand the latest de
An analysis of the extension of a ZnO piezoelectric semiconductor nanofiber under an axial force
Zhang, Chunli; Wang, Xiaoyuan; Chen, Weiqiu; Yang, Jiashi
2017-02-01
This paper presents a theoretical analysis on the axial extension of an n-type ZnO piezoelectric semiconductor nanofiber under an axial force. The phenomenological theory of piezoelectric semiconductors consisting of Newton’s second law of motion, the charge equation of electrostatics and the conservation of charge was used. The equations were linearized for small axial force and hence small electron concentration perturbation, and were reduced to one-dimensional equations for thin fibers. Simple and analytical expressions for the electromechanical fields and electron concentration in the fiber were obtained. The fields are either totally or partially described by hyperbolic functions relatively large near the ends of the fiber and change rapidly there. The behavior of the fields is sensitive to the initial electron concentration and the applied axial force. For higher initial electron concentrations the fields are larger near the ends and change more rapidly there.
Nonlinear Analysis of Experimental Measurements 7.6. Theoretical Chemistry
2015-01-26
manuscript under consideration in Biophysical Journal. d) Coherent energy transfer in photosynthetic light -harvesting systems In photosynthesis ...Menten equation for enzymatic reactions ; (b) counting statistics of single molecule reaction trajectories and single cell microarray data (c) analysis...of cytoadhesion and binding kinetics experiments; and (d) optimization of coherent energy transfer in photosynthetic light -harvesting systems. The
An Optimality-Theoretic Analysis of Codas in Brazilian Portuguese
Goodin-Mayeda, C. Elizabeth
2015-01-01
Brazilian Portuguese allows only /s, N, l, r/ syllable finally, and of these, only /s/ is realized faithfully (as well as /r/ for some speakers). In order to avoid unacceptable codas, dialects of Brazilian Portuguese employ such strategies as epenthesis, nasal absorption, debucalization, and gliding. The current analysis argues that codas in…
An Optimality-Theoretic Analysis of Codas in Brazilian Portuguese
Goodin-Mayeda, C. Elizabeth
2015-01-01
Brazilian Portuguese allows only /s, N, l, r/ syllable finally, and of these, only /s/ is realized faithfully (as well as /r/ for some speakers). In order to avoid unacceptable codas, dialects of Brazilian Portuguese employ such strategies as epenthesis, nasal absorption, debucalization, and gliding. The current analysis argues that codas in…
Theoretical concepts of X-ray nanoscale analysis theory and applications
Benediktovitch, Andrei; Ulyanenkov, Alexander
2013-01-01
This book provides a concise survey of modern theoretical concepts of X-ray materials analysis. The principle features of the book are: basics of X-ray scattering, interaction between X-rays and matter and new theoretical concepts of X-ray scattering. The various X-ray techniques are considered in detail: high-resolution X-ray diffraction, X-ray reflectivity, grazing-incidence small-angle X-ray scattering and X-ray residual stress analysis. All the theoretical methods presented use the unified physical approach. This makes the book especially useful for readers learning and performing data ana
Experiment and Theoretical Analysis Study of ETFE Inflatable Tubes
Directory of Open Access Journals (Sweden)
YanLi He
2014-01-01
Full Text Available The load bearing capacity of an ETFE (ethylene-tetra-fluoro-ethylene inflatable tube is tested in this paper, and a comparative study of two wrinkling theories, the bifurcation theory and the tension field theory, is carried out for wrinkling analysis of the ETFE inflatable tube. Results obtained from the bifurcation theory and experiment reveal the limitations of tension field theory on the wrinkling analysis. The load-displacement curves of inflatable beams under bending load are obtained and compared with the experimental results; curves obtained using the bifurcation theory show coincidence with experimental curves, but the curves obtained using the tension field theory have noticeable deviations between calculated and experimental results.
Directory of Open Access Journals (Sweden)
Veronice Veronice
2015-08-01
Full Text Available The science and technology is developing rapidly with the demands of changing times. The development of information and communication technology, especially since the advent of internet technology has led to major changes in society. Information technology products are relatively cheap and affordable facilitate access to information beyond the national borders and cultural boundaries. This condition has penetrated to all levels of human life, including farmers in the villages. Therefore, the extension becomes important role as a facilitator in developing the potential of farmers. Consequently extension is required to adjust to the changes and demands of the growing community. The objectives of the research is the analysis of characteristics extension workers to utilization of information and communication technology in Limapuluh Kota regency West Sumatera. This study is a descriptive-correlational survey-based study with the sample consisting of government employee as well as freelance extension workers in 8 Extension Agency of Agriculture Fisheries and Forestry Extension (BP3K in Limapuluh Kota regency, West Sumatera province. Based on the results obtained, the results of different test (t-test is known that there are significant differences between the characteristics of the civil servants and THL-TBPP especially in the aspect of age and length of employment.
Directory of Open Access Journals (Sweden)
Hui-Jing Li
2014-03-01
Full Text Available Electrophilic aromatic bromination is the most common synthetic method used to prepare aryl bromides, which are very useful intermediates in organic synthesis. To understand the experimental results in electrophilic aromatic brominations, ab initio calculations are used here for a tentative analysis of the positional selectivity. The calculated results agree well with the corresponding experimental data, and the reliability of the resulting positional selectivity was verified by the corresponding experimental data.
THEORETICAL ANALYSIS OF THE CONCEPT OF INSURANCE PORTFOLIO OF INSURER
Kondratenko, D.
2014-01-01
The article is devoted to the analysis of the different interpretations of the concept of "portfolio insurance". The examples of the essence understanding of the “portfolio insurance'' concept from the different scholars point of view was examined from the perspective of the aggregate insurance risks and the number of contracts or assets incepted for the insurance. The functions and principles of the insurance portfoli were designated. It has been established that the current legislation does...
Dissecting Situational Strength: Theoretical Analysis and Empirical Tests
2012-09-01
approaches such as difference scores and profile similarity indices (see Edwards , 2007; Shanock, Baran, Gentry, Pattison, & Heggestad, 2010). In addition...and (2) via analysis of indirect, actual measures of fit through polynomial regression and response surfaces ( Edwards , 2007; Shanock et al., 2010...Thoresen, Bono , & Patton, 2001; see also Herman, 1973; Smith, 1977) suggests that job attitudes are related to job performance more strongly in situations
Quantitative analysis on the urban flood mitigation effect by the extensive green roof system.
Lee, J Y; Moon, H J; Kim, T I; Kim, H W; Han, M Y
2013-10-01
Extensive green-roof systems are expected to have a synergetic effect in mitigating urban runoff, decreasing temperature and supplying water to a building. Mitigation of runoff through rainwater retention requires the effective design of a green-roof catchment. This study identified how to improve building runoff mitigation through quantitative analysis of an extensive green-roof system. Quantitative analysis of green-roof runoff characteristics indicated that the extensive green roof has a high water-retaining capacity response to rainfall of less than 20 mm/h. As the rainfall intensity increased, the water-retaining capacity decreased. The catchment efficiency of an extensive green roof ranged from 0.44 to 0.52, indicating reduced runoff comparing with efficiency of 0.9 for a concrete roof. Therefore, extensive green roofs are an effective storm water best-management practice and the proposed parameters can be applied to an algorithm for rainwater-harvesting tank design. © 2013 Elsevier Ltd. All rights reserved.
Directory of Open Access Journals (Sweden)
Veronice Veronice
2015-01-01
Full Text Available Extension placed man as the subject of development and human capital to develop into independent and empowered (dignity in adapting to the environment, thus being able to improve the quality of life for themselves, their families and communities. It is therefore necessary professional competence standard extension clear and effective controls in carrying counseling profession domination supported by Information and Communication Technology (ICT. This research aimed to analyze the relationship between the level of competency with the level of ICT use by the extension workers. The study was designed as a descriptive survey research correlational ,which was observed by quantitative analysis approach that is supported by descriptive and inferential statistic analysis. The study was conducted in Bogor Regency,West Java Province. Based on this research can be concluded level of ICT utilization in the range of aspects related resources are very real to the competence of extension on the capability of understanding the potential of the region, entrepreneurial ability and the ability of the system guides the network, while the variation of the material aspects of counseling and a variety of related information is very real with all levels of competence extension.
Hydraulically interconnected vehicle suspension: theoretical and experimental ride analysis
Smith, Wade A.; Zhang, Nong; Jeyakumaran, Jeku
2010-01-01
In this paper, a previously derived model for the frequency-domain analysis of vehicles with hydraulically interconnected suspension (HIS) systems is applied to the ride analysis of a four-degrees of freedom roll-plane, half-car under a rough road input. The entire road surface is assumed to be a realisation of a two-dimensional Gaussian homogenous and isotropic random process. The frequency responses of the half-car, in terms of bounce and roll acceleration, suspension deflection and dynamic tyre forces, are obtained under the road input of a single profile represented by its power spectral density function. Simulation results obtained for the roll-plane half-car fitted with an HIS and those with conventional suspensions are compared in detail. In addition, sensitivity analysis of key parameters of the HIS to the ride performance is carried out through simulations. The paper also presents the experimental validation of the analytical results of the free and forced vibrations of the roll-plane half-car. The hydraulic and mechanical system layouts, data acquisition system and the external force actuation mechanism of the test set-up are described in detail. The methodology for free and forced vibration tests and the application of mathematical models to account for the effective damper valve pressure loss are explained. Results are provided for the free and forced vibration testing of the half-car with different mean operating pressures. Comparisons are also given between the test results and those obtained from the system model with estimated damper valve loss coefficients. Furthermore, discussions on the deficiencies and practical implications of the proposed model and suggestions for future investigation are provided. Finally, the key findings of the investigation on the ride performance of the roll-plane half-car are summarised.
A theoretical analysis of the median LMF adaptive algorithm
DEFF Research Database (Denmark)
Bysted, Tommy Kristensen; Rusu, C.
1999-01-01
Higher order adaptive algorithms are sensitive to impulse interference. In the case of the LMF (Least Mean Fourth), an easy and effective way to reduce this is to median filter the instantaneous gradient of the LMF algorithm. Although previous published simulations have indicated that this reduces...... the speed of convergence, no analytical studies have yet been made to prove this. In order to enhance the usability, this paper presents a convergence and steady-state analysis of the median LMF adaptive algorithm. As expected this proves that the median LMF has a slower convergence and a lower steady...
Environmental accounting in Spain: structured review process and theoretical analysis
Directory of Open Access Journals (Sweden)
Fabricia Silva da Rosa
2012-12-01
Full Text Available One way to perceive and understand the level of development of environmental accounting is to study the main features of its publications. Thus, the purpose of this paper is to identify and analyze the profile of Spanish publications in accounting journals. To this end, 15 journals were selected and analyzed 74 articles in the period 2001 to 2010. The results show that the peak years of publication are 2001, 2003 and 2006, and authors with more articles in the sample are Moneva Abadía, Larrinaga González, Fernández Cuesta and Archel Domench. In terms of methodology, the works of review, case studies and content analysis, addressing standardization issues, fundamentals of environmental accounting, environmental sustainability indicators and reporting.
Theoretical analysis of BLM system for HLS II
Yukai, Chen; Lijuan, He; Weimin, Li
2014-01-01
Hefei Light Source (HLS) is being upgraded to HLS II. Its emittance will be much lower than before, therefore the Touschek scattering will increase significantly and become the dominant factor of beam loss. So it is necessary to build a new beam loss monitoring (BLM) system differed from the old one to obtain the quantity and position information of lost electrons. This information is useful in the commissioning, troubleshooting and beam lifetime studying for HLS II. This paper analyzes the distribution features of different kinds of lost electrons, introduces the new machine's operation parameters and discusses the way to choose proper monitoring positions. Base on these comprehensive analysis, a new BLM system for HLS II is proposed.
Theoretical analysis and simulation of thermoelastic deformation of bimorph microbeams
Institute of Scientific and Technical Information of China (English)
SHANG; YuanFang; YE; XiongYing; FENG; JinYang
2013-01-01
In this paper, a purely mechanical model for the thermoelastic behavior of a bimorph microbeam is presented. The thermoelastic coupling problem of the microbeam is converted to a mechanical problem by simply replacing the thermal stress in the beam with a bulk force and a surface force. Thermoelastic deformation of the bimorph microbeams with constraints frequently used in micro-electro-mechanical systems (MEMS) devices has been derived based on this model and is characterized by FEA simulation. Coincidence of the results from theory and simulation demonstrates the validity of the model. The analysis shows that a bimorph microbeam with a soft constraint and a uniform temperature field has a larger thermoelastic deformation than that with a hard constraint and a linear temperature field. In addition to the adoption of materials with large CTE mismatch,thickness ratio and length ratio of the two layers need to be optimized to get a large thermoelastic deformation.
Motility of a model bristle-bot: A theoretical analysis
Cicconofri, Giancarlo; DeSimone, Antonio
2015-11-01
Bristle-bots are legged robots that can be easily made out of a toothbrush head and a small vibrating engine. Despite their simple appearance, the mechanism enabling them to propel themselves by exploiting friction with the substrate is far from trivial. Numerical experiments on a model bristle-bot have been able to reproduce such a mechanism revealing, in addition, the ability to switch direction of motion by varying the vibration frequency. This paper provides a detailed account of these phenomena through a fully analytical treatment of the model. The equations of motion are solved through an expansion in terms of a properly chosen small parameter. The convergence of the expansion is rigorously proven. In addition, the analysis delivers formulas for the average velocity of the robot and for the frequency at which the direction switch takes place. A quantitative description of the mechanism for the friction modulation underlying the motility of the bristle-bot is also provided.
Information-theoretic analysis of MIMO channel sounding
Baum, Daniel S
2007-01-01
The large majority of commercially available multiple-input multiple-output (MIMO) radio channel measurement devices (sounders) is based on time-division multiplexed switching (TDMS) of a single transmit/receive radio-frequency chain into the elements of a transmit/receive antenna array. While being cost-effective, such a solution can cause significant measurement errors due to phase noise and frequency offset in the local oscillators. In this paper, we systematically analyze the resulting errors and show that, in practice, overestimation of channel capacity by several hundred percent can occur. Overestimation is caused by phase noise (and to a lesser extent frequency offset) leading to an increase of the MIMO channel rank. Our analysis furthermore reveals that the impact of phase errors is, in general, most pronounced if the physical channel has low rank (typical for line-of-sight or poor scattering scenarios). The extreme case of a rank-1 physical channel is analyzed in detail. Finally, we present measureme...
Theoretical analysis of the flow around a Savonius rotor
Energy Technology Data Exchange (ETDEWEB)
Aouachria, Z.; Djoumati, D. [Batna Univ., Batna (Algeria). Laboratoire de Physique Energetique Appliquee; Djamel, H. [Batna Univ., Batna (Algeria). Dept. de Mecanique Energetique
2009-07-01
While Savonius rotors do not perform as well as Darrieus wind turbine rotors, Savonius rotors work in all wind directions, do not require a rudder, and are capable of operating at relatively low speeds. A discrete vortex method was used to analyze the complex flow around a Savonius rotor. Velocity and pressure fields obtained in the analysis were used to determine both mechanical and energetic rotor performance. Savonius rotor bi-blades were considered in relation to 4 free eddies, the leakage points of each blade, and the distribution of basic eddies along the blades. Each blade was divided into equal elementary arcs. Linear equations and Kelvin theorem were reduced to a single equation. Results showed good agreement with data obtained in previous experimental studies. The study demonstrated that vortice emissions were unbalanced. The resistant blade had 2 vortice emissions, while the driving blade had only a single vortex. The results of the study will be used to clarify the mechanical and aerodynamic functions as well as to determine the different values between the blades and the speed of the turbine's engine. 9 refs., 4 figs.
Spectral derivative analysis of solar spectroradiometric measurements: Theoretical basis
Hansell, R. A.; Tsay, S.-C.; Pantina, P.; Lewis, J. R.; Ji, Q.; Herman, J. R.
2014-07-01
Spectral derivative analysis, a commonly used tool in analytical spectroscopy, is described for studying cirrus clouds and aerosols using hyperspectral, remote sensing data. The methodology employs spectral measurements from the 2006 Biomass-burning Aerosols in Southeast Asia field study to demonstrate the approach. Spectral peaks associated with the first two derivatives of measured/modeled transmitted spectral fluxes are examined in terms of their shapes, magnitudes, and positions from 350 to 750 nm, where variability is largest. Differences in spectral features between media are mainly associated with particle size and imaginary term of the complex refractive index. Differences in derivative spectra permit cirrus to be conservatively detected at optical depths near the optical thin limit of ~0.03 and yield valuable insight into the composition and hygroscopic nature of aerosols. Biomass-burning smoke aerosols/cirrus generally exhibit positive/negative slopes, respectively, across the 500-700 nm spectral band. The effect of cirrus in combined media is to increase/decrease the slope as cloud optical thickness decreases/increases. For thick cirrus, the slope tends to 0. An algorithm is also presented which employs a two model fit of derivative spectra for determining relative contributions of aerosols/clouds to measured data, thus enabling the optical thickness of the media to be partitioned. For the cases examined, aerosols/clouds explain ~83%/17% of the spectral signatures, respectively, yielding a mean cirrus cloud optical thickness of 0.08 ± 0.03, which compared reasonably well with those retrieved from a collocated Micropulse Lidar Network Instrument (0.09 ± 0.04). This method permits extracting the maximum informational content from hyperspectral data for atmospheric remote sensing applications.
Directory of Open Access Journals (Sweden)
Jonathan Laney
2015-01-01
Full Text Available The assessment of neuroplasticity after stroke through functional magnetic resonance imaging (fMRI analysis is a developing field where the objective is to better understand the neural process of recovery and to better target rehabilitation interventions. The challenge in this population stems from the large amount of individual spatial variability and the need to summarize entire brain maps by generating simple, yet discriminating features to highlight differences in functional connectivity. Independent vector analysis (IVA has been shown to provide superior performance in preserving subject variability when compared with widely used methods such as group independent component analysis. Hence, in this paper, graph-theoretical (GT analysis is applied to IVA-generated components to effectively exploit the individual subjects' connectivity to produce discriminative features. The analysis is performed on fMRI data collected from individuals with chronic stroke both before and after a 6-week arm and hand rehabilitation intervention. Resulting GT features are shown to capture connectivity changes that are not evident through direct comparison of the group t-maps. The GT features revealed increased small worldness across components and greater centrality in key motor networks as a result of the intervention, suggesting improved efficiency in neural communication. Clinically, these results bring forth new possibilities as a means to observe the neural processes underlying improvements in motor function.
Theoretical analysis of droplet transition from Cassie to Wenzel state
Institute of Scientific and Technical Information of China (English)
刘天庆; 李艳杰; 李香琴; 孙玮
2015-01-01
Whether droplets transit from the Cassie to the Wenzel state (C–W) on a textured surface is the touchstone that the superhydrophobicity of the surface is still maintained. However, the C–W transition mechanism, especially the spontaneous transition of small droplets, is still not very clear to date. The interface free energy gradient of a small droplet is firstly proposed and derived as the driving force for its C–W evolution in this study based on the energy and gradient analysis. Then the physical and mathematical model of the C–W transition is found after the C–W driving force or transition pressure, the resistance, and the parameters of the meniscus beneath the droplet are formulated. The results show that the micro/nano structural parameters significantly affect the C–W driving force and resistance. The smaller the pillar diameter and pitch, the minor the C–W transition pressure, and the larger the resistance. Consequently, the C–W transition is difficult to be completed for the droplets on nano-textured surfaces. Meanwhile if the posts are too short, the front of the curved liquid–air interface below the droplet will touch the structural substrate easily even though the three phase contact line (TPCL) has not depinned. When the posts are high enough, the TPCL beneath the drop must move firstly before the meniscus can reach the substrate. As a result, the droplet on a textured surface with short pillars is easy to complete its C–W evolution. On the other hand, the smaller the droplet, the easier the C–W shift, since the transition pressure becomes larger, which well explains why an evaporating drop will collapse spontaneously from composite to Wenzel state. Besides, both intrinsic and advancing contact angles affect the C–W transition as well. The greater the two angles, the harder the C–W transition. In the end, the C–W transition parameters and the critical conditions measured in literatures are calculated and compared, and the
Theoretical analysis of oxygen supply to contracted skeletal muscle.
Groebe, K; Thews, G
1986-01-01
Honig and collaborators reported striking contradictions in current understanding of O2 supply to working skeletal muscle. Therefore we re-examined the problem by means of a new composite computer simulation. As inclusion of erythrocytic O2 desaturation and oxygen transport and consumption inside the muscle cell into a single model would entail immense numerical difficulties, we broke up the whole process into its several components: O2 desaturation of erythrocytes O2 transport and consumption in muscle fiber capillary transit time characterizing the period of contact between red cell and muscle fiber. "Erythrocyte model" as well as "muscle fiber model" both consist of a central core cylinder surrounded by a concentric diffusion layer representing the extracellular resistance to O2 diffusion (Fig. 1). Resistance layers in both models are to be conceived of as one and the same anatomical structure--even though in each model their shape is adapted to the respective geometry. By means of this overlap region a spatial connexion between both is given, whereas temporal coherence governing O2 fluxes and red cell spacing is derived from capillary transit time. Analysis of individual components is outlined as follows: Assuming axial symmetry of the problem a numerical algorithm was employed to solve the parabolic system of partial differential equations describing red cell O2 desaturation. Hb-O2 reaction kinetics, free and facilitated O2 diffusion in axial and radial directions, and red cell movement in capillary were considered. Resulting time courses of desaturation, which are considerably faster than the ones computed by Honig et al., are given in the following table (see also Fig. 3). (Formula: see text) Furthermore, we studied the respective importance of the several processes included in our model: Omission of longitudinal diffusion increased desaturation time by 15% to 23%, whereas effects of reaction kinetics and axial movement were 5% and 2% respectively. For time
Theoretical foundations of functional data analysis, with an introduction to linear operators
Hsing, Tailen
2015-01-01
Theoretical Foundations of Functional Data Analysis, with an Introduction to Linear Operators provides a uniquely broad compendium of the key mathematical concepts and results that are relevant for the theoretical development of functional data analysis (FDA).The self-contained treatment of selected topics of functional analysis and operator theory includes reproducing kernel Hilbert spaces, singular value decomposition of compact operators on Hilbert spaces and perturbation theory for both self-adjoint and non self-adjoint operators. The probabilistic foundation for FDA is described from the
1979-01-01
An array deployment assembly, power regulation and control assembly, the necessary interface, and display and control equipment comprise the power extension package (PEP) which is designed to provide increased power and duration, as well as reduce fuel cell cryogen consumption during Spacelab missions. Compatible with all currently defined missions and payloads, PEP imposes minimal weight and volume penalties on sortie missions, and can be installed and removed as needed at the launch site within the normal Orbiter turnaround cycle. The technology on which it is based consists of a modified solar electric propulsion array, standard design regulator and control equipment, and a minimally modified Orbiter design. The requirements from which PEP was derived, and the system and its performance capabilities are described. Features of the recommended project are presented.
A review of ADM1 extensions, applications, and analysis: 2002-2005.
Batstone, D J; Keller, J; Steyer, J P
2006-01-01
Since publication of the Scientific and Technical Report (STR) describing the ADM1, the model has been extensively used, and analysed in both academic and practical applications. Adoption of the ADM1 in popular systems analysis tools such as the new wastewater benchmark (BSM2), and its use as a virtual industrial system can stimulate modelling of anaerobic processes by researchers and practitioners outside the core expertise of anaerobic processes. It has been used as a default structural element that allows researchers to concentrate on new extensions such as sulfate reduction, and new applications such as distributed parameter modelling of biofilms. The key limitations for anaerobic modelling originally identified in the STR were: (i) regulation of products from glucose fermentation, (ii) parameter values, and variability, and (iii) specific extensions. Parameter analysis has been widespread, and some detailed extensions have been developed (e.g., sulfate reduction). A verified extension that describes regulation of products from glucose fermentation is still limited, though there are promising fundamental approaches. This is a critical issue, given the current interest in renewable hydrogen production from carbohydrate-type waste. Critical analysis of the model has mainly focused on model structure reduction, hydrogen inhibition functions, and the default parameter set recommended in the STR. This default parameter set has largely been verified as a reasonable compromise, especially for wastewater sludge digestion. One criticism of note is that the ADM1 stoichiometry focuses on catabolism rather than anabolism. This means that inorganic carbon can be used unrealistically as a carbon source during some anabolic reactions. Advances and novel applications have also been made in the present issue, which focuses on the ADM1. These papers also explore a number of novel areas not originally envisaged in this review.
A Theoretical Analysis of Potential Extinction Properties of Behavior-Specific Manual Restraint
Cipani, Ennio; Thomas, Melvin; Martin, Daniel
2007-01-01
This paper will examine possible extinction properties of behavior-specific manual restraint. It will analyze the possibility of extinction being produced via restraint with respect to the target behavior's possible environmental functions. The theoretical analysis will involve the analysis of behavioral properties of restraint during two temporal…
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…
Multijoint kinetic chain analysis of knee extension during the soccer instep kick.
Naito, Kozo; Fukui, Yosuke; Maruyama, Takeo
2010-04-01
Although previous studies have shown that motion-dependent interactions between adjacent segments play an important role in producing knee extension during the soccer instep kick, detailed knowledge about the mechanisms underlying those interactions is lacking. The present study aimed to develop a 3-D dynamical model for the multijoint kinetic chain of the instep kick in order to quantify the contributions of the causal dynamical factors to the production of maximum angular velocity during knee extension. Nine collegiate soccer players volunteered to participate in the experiment and performed instep kicking movements while 3-D positional data and the ground reaction force were measured. A dynamical model was developed in the form of a linked system containing 8 segments and 18 joint rotations, and the knee extension/flexion motion was decomposed into causal factors related to muscular moment, gyroscopic moment, centrifugal force, Coriolis force, gravity, proximal endpoint linear acceleration, and external force-dependent terms. The rapid knee extension during instep kicking was found to result almost entirely from kicking leg centrifugal force, trunk rotation muscular moment, kicking leg Coriolis force, and trunk rotation gyroscopic-dependent components. Based on the finding that rapid knee extension during instep kicking stems from multiple dynamical factors, it is suggested that the multijoint kinetic chain analysis used in the present study is more useful for achieving a detailed understanding of the cause of rapid kicking leg movement than the previously used 2-D, two-segment kinetic chain model. The present results also indicated that the centrifugal effect due to the kicking hip flexion angular velocity contributed substantially to the generation of a rapid knee extension, suggesting that the adjustment between the kicking hip flexion angular velocity and the leg configuration (knee flexion angle) is more important for effective instep kicking than other
Systematic analysis of transverse momentum distribution and non-extensive thermodynamics theory
Sena, I
2012-01-01
A systematic analysis of transverse momentum distribution of hadrons produced in ultra-relativistic $p+p$ and $A+A$ collisions is presented. We investigate the effective temperature and the entropic parameter from the non-extensive thermodynamic theory of strong interaction. We conclude that the existence of a limiting effective temperature and of a limiting entropic parameter is in accordance with experimental data.
Pang, Y. F.
2016-08-01
The traditional limiting conditions have the biggest refrigeration quantity condition and the biggest refrigeration coefficient condition, there is a special operating mode during these conditions, enabling to both have the big refrigeration quantity and the small power loss, this operating mode is “Optimum condition”. This article first carried on the theoretical analysis to the semiconductor's optimum condition, inferred optimum electric current's theoretical formula; Carried on the experiment again to a semiconductor refrigeration box by regulating current changing operating mode, which had analyzed performance parameter's change situation under 8 kinds of condition experiments, carried on the regression analysis to the experimental data, obtained the regression equation thus discovered optimum electric current corresponding optimum condition. Carried on working under this condition, and then obtained the big refrigeration quantity and small power, which enhanced the refrigeration performance of semiconductor refrigerator. The experimental result and the theoretical analysis result tallied basically.
An in-depth analysis of theoretical frameworks for the study of care coordination
Directory of Open Access Journals (Sweden)
Sabine Van Houdt
2013-06-01
Full Text Available Introduction: Complex chronic conditions often require long-term care from various healthcare professionals. Thus, maintaining quality care requires care coordination. Concepts for the study of care coordination require clarification to develop, study and evaluate coordination strategies. In 2007, the Agency for Healthcare Research and Quality defined care coordination and proposed five theoretical frameworks for exploring care coordination. This study aimed to update current theoretical frameworks and clarify key concepts related to care coordination. Methods: We performed a literature review to update existing theoretical frameworks. An in-depth analysis of these theoretical frameworks was conducted to formulate key concepts related to care coordination.Results: Our literature review found seven previously unidentified theoretical frameworks for studying care coordination. The in-depth analysis identified fourteen key concepts that the theoretical frameworks addressed. These were ‘external factors’, ‘structure’, ‘tasks characteristics’, ‘cultural factors’, ‘knowledge and technology’, ‘need for coordination’, ‘administrative operational processes’, ‘exchange of information’, ‘goals’, ‘roles’, ‘quality of relationship’, ‘patient outcome’, ‘team outcome’, and ‘(interorganizational outcome’.Conclusion: These 14 interrelated key concepts provide a base to develop or choose a framework for studying care coordination. The relational coordination theory and the multi-level framework are interesting as these are the most comprehensive.
An in-depth analysis of theoretical frameworks for the study of care coordination
Directory of Open Access Journals (Sweden)
Sabine Van Houdt
2013-06-01
Full Text Available Introduction: Complex chronic conditions often require long-term care from various healthcare professionals. Thus, maintaining quality care requires care coordination. Concepts for the study of care coordination require clarification to develop, study and evaluate coordination strategies. In 2007, the Agency for Healthcare Research and Quality defined care coordination and proposed five theoretical frameworks for exploring care coordination. This study aimed to update current theoretical frameworks and clarify key concepts related to care coordination. Methods: We performed a literature review to update existing theoretical frameworks. An in-depth analysis of these theoretical frameworks was conducted to formulate key concepts related to care coordination. Results: Our literature review found seven previously unidentified theoretical frameworks for studying care coordination. The in-depth analysis identified fourteen key concepts that the theoretical frameworks addressed. These were ‘external factors’, ‘structure’, ‘tasks characteristics’, ‘cultural factors’, ‘knowledge and technology’, ‘need for coordination’, ‘administrative operational processes’, ‘exchange of information’, ‘goals’, ‘roles’, ‘quality of relationship’, ‘patient outcome’, ‘team outcome’, and ‘(interorganizational outcome’. Conclusion: These 14 interrelated key concepts provide a base to develop or choose a framework for studying care coordination. The relational coordination theory and the multi-level framework are interesting as these are the most comprehensive.
Experimental and Theoretical Analysis of Hollow Steel Columns Strengthening by CFRP
Directory of Open Access Journals (Sweden)
Keykha A.H.
2015-09-01
Full Text Available The need for strengthening and retrofitting is well known and extensive research is progressing in this field. The reasons for strengthening and retrofitting are numerous: increased loads, changes in use, deterioration, and so on. In recent years, the use of carbon fiber reinforced polymer (CFRP for strengthening has shown to be a competitive method, both regarding structural performance, and economical aspects. Extensive research has been carried out in this field. However, most of the research has been undertaken on concrete structures and for confinement, flexural, and shear strengthening. Limited research has been carried out on steel structures strengthened with CFRP. This paper presents axially loaded steel columns strengthened for increased load. The topic is studied theoretically and through laboratory tests. The theory covers analytical methods. Carbon fiber reinforced polymers has been used to strengthen the columns. The tests have been undertaken on full scale specimens, non-strengthened for reference, partially strengthened and fully strengthened
Theoretical analysis and experimental research on port/starboard discrimination in towed line array
Institute of Scientific and Technical Information of China (English)
DU Xuanmin; ZHU Daizhu; ZHAO Rongrong; YAO Lan
2001-01-01
The theoretical analysis and experimental research on Port/Starboard (P/S) discrimination in towed line array are proposed. Two methods resolving the P/S ambiguity with hydrophone triplets are introduced. By processing experimental data, the theoretical analysis is verified. The processing algorithm is extended to broadband signal. The research results show that the method based on optimum beamforming with triplets can be used to remove the port/starboard ambiguity. Also because of the simplicity of the method, it is expected to be implemented in practical towed line array sonar.
Small-Body Extensions for the Satellite Orbit Analysis Program (SOAP)
Carnright, Robert; Stodden, David; Coggi, John
2008-01-01
An extension to the SOAP software allows users to work with tri-axial ellipsoid-based representations of planetary bodies, primarily for working with small, natural satellites, asteroids, and comets. SOAP is a widely used tool for the visualization and analysis of space missions. The small body extension provides the same visualization and analysis constructs for use with small bodies. These constructs allow the user to characterize satellite path and instrument cover information for small bodies in both 3D display and numerical output formats. Tri-axial ellipsoids are geometric shapes the diameters of which are different in each of three principal x, y, and z dimensions. This construct provides a better approximation than using spheres or oblate spheroids (ellipsoids comprising two common equatorial diameters as a distinct polar diameter). However, the tri-axial ellipsoid is considerably more difficult to work with from a modeling perspective. In addition, the SOAP small-body extensions allow the user to actually employ a plate model for highly irregular surfaces. Both tri-axial ellipsoids and plate models can be assigned to coordinate frames, thus allowing for the modeling of arbitrary changes to body orientation. A variety of features have been extended to support tri-axial ellipsoids, including the computation and display of the spacecraft sub-orbital point, ground trace, instrument footprints, and swathes. Displays of 3D instrument volumes can be shown interacting with the ellipsoids. Longitude/latitude grids, contour plots, and texture maps can be displayed on the ellipsoids using a variety of projections. The distance along an arbitrary line of sight can be computed between the spacecraft and the ellipsoid, and the coordinates of that intersection can be plotted as a function of time. The small-body extension supports the same visual and analytical constructs that are supported for spheres and oblate spheroids in SOAP making the implementation of the more
Kraemer, Lars; Beszteri, Bánk; Gäbler-Schwarz, Steffi; Held, Christoph; Leese, Florian; Mayer, Christoph; Pöhlmann, Kevin; Frickenhaus, Stephan
2009-01-30
Microsatellites (MSs) are DNA markers with high analytical power, which are widely used in population genetics, genetic mapping, and forensic studies. Currently available software solutions for high-throughput MS design (i) have shortcomings in detecting and distinguishing imperfect and perfect MSs, (ii) lack often necessary interactive design steps, and (iii) do not allow for the development of primers for multiplex amplifications. We present a set of new tools implemented as extensions to the STADEN package, which provides the backbone functionality for flexible sequence analysis workflows. The possibility to assemble overlapping reads into unique contigs (provided by the base functionality of the STADEN package) is important to avoid developing redundant markers, a feature missing from most other similar tools. Our extensions to the STADEN package provide the following functionality to facilitate microsatellite (and also minisatellite) marker design: The new modules (i) integrate the state-of-the-art tandem repeat detection and analysis software PHOBOS into workflows, (ii) provide two separate repeat detection steps - with different search criteria - one for masking repetitive regions during assembly of sequencing reads and the other for designing repeat-flanking primers for MS candidate loci, (iii) incorporate the widely used primer design program PRIMER3 into STADEN workflows, enabling the interactive design and visualization of flanking primers for microsatellites, and (iv) provide the functionality to find optimal locus- and primer pair combinations for multiplex primer design. Furthermore, our extensions include a module for storing analysis results in an SQLite database, providing a transparent solution for data access from within as well as from outside of the STADEN Package. The STADEN package is enhanced by our modules into a highly flexible, high-throughput, interactive tool for conventional and multiplex microsatellite marker design. It gives the user
Institute of Scientific and Technical Information of China (English)
无
2002-01-01
Time domain ABCD matrix formalism is a useful model for analyzing the characteristics of actively modelocked fiber laser. Based on this model and given more consideration on the influences of optical fiber dispersion and optical fiber nonlinearity, the laser characteristic of actively modelocked fiber laser is analyzed, and the comparision of the theoretical analysis results with experimental ones is given.
DEFF Research Database (Denmark)
Tsilipakos, O.; Pitilakis, A.; Yioultsis, T. V.
2012-01-01
A comprehensive theoretical analysis of end-fire coupling between dielectric-loaded surface plasmon polariton and rib/wire silicon-on-insulator (SOI) waveguides is presented. Simulations are based on the 3-D vector finite element method. The geometrical parameters of the interface are varied...
Metaphor Analysis as an Approach for Exploring Theoretical Concepts: The Case of Social Capital
Andriessen, Daniel; Gubbins, Claire
2009-01-01
In many fields within management and organizational literature there is considerable debate and controversy about key theoretical concepts and their definitions and meanings. Systematic metaphor analysis can be a useful approach to study the underlying conceptualizations that give rise to these cont
Security Analysis of Selected AMI Failure Scenarios Using Agent Based Game Theoretic Simulation
Energy Technology Data Exchange (ETDEWEB)
Abercrombie, Robert K [ORNL; Schlicher, Bob G [ORNL; Sheldon, Frederick T [ORNL
2014-01-01
Information security analysis can be performed using game theory implemented in dynamic Agent Based Game Theoretic (ABGT) simulations. Such simulations can be verified with the results from game theory analysis and further used to explore larger scale, real world scenarios involving multiple attackers, defenders, and information assets. We concentrated our analysis on the Advanced Metering Infrastructure (AMI) functional domain which the National Electric Sector Cyber security Organization Resource (NESCOR) working group has currently documented 29 failure scenarios. The strategy for the game was developed by analyzing five electric sector representative failure scenarios contained in the AMI functional domain. From these five selected scenarios, we characterize them into three specific threat categories affecting confidentiality, integrity and availability (CIA). The analysis using our ABGT simulation demonstrates how to model the AMI functional domain using a set of rationalized game theoretic rules decomposed from the failure scenarios in terms of how those scenarios might impact the AMI network with respect to CIA.
Theoretical Analysis of TCS with a Comparison to HGS in Characteristics
Institute of Scientific and Technical Information of China (English)
侯培民
2001-01-01
A theoretical analysis of TCS is provided to explain the structure evolution along the filament during processing.This analysis based on the spinning process kinematics incorporates the constitutive equation of PET polymer, a convection and radiation combining procedure in the thermal channel, and takinginto account the nonisothermal crystallization kinetics. The characteristics of the fiber so-produced are compared with those produced by HGS.
Theoretical analysis of the acoustical characteristics of suspended micro-perforated panel absorbers
Institute of Scientific and Technical Information of China (English)
SHENG Shengwo; SONG Yongmin; WANG Jiqing
2005-01-01
Sound absorption characteristics of suspended micro-perforated panel absorbers were investigated theoretically. The method of half thickness model of such panel absorber with quadripole analysis was used for predicting its acoustic performance. The analysis results show that the predictions agree well with the measurements of absorption in the reverberation chamber. The factors affecting the absorption characteristics for such absorbers were discussed,and some rules as design guidelines were given.
[Assessment of ultraviolet radiation penetration into human skin. I. Theoretical analysis].
Cader, A; Jankowski, J
1995-01-01
This is one of the two articles under the same title "Assessment of ultraviolet radiation penetrating into human skin" which are aimed at presenting a part of broader studies in this area. They drive at identifying biophysical aspects of the effects of ultraviolet radiation on human skin. In order to characterise such parameters as UV reflectance from the skin surface of UV absorption and dispersion coefficients, it is necessary to develop appropriate methods. In Part I--"Theoretical analysis", theoretical principles for interpreting measurements of radiation dispersed in different geometrical configurations are presented. They can serve as a basis for estimating the values of UV linear absorption and dispersion coefficients in skin tissues.
THEORETICAL ANALYSIS OF COORDINATES MEASUREMENT BY FLEXIBLE 3D MEASURING SYSTEM
Institute of Scientific and Technical Information of China (English)
ZHANG Guoyu; SUN Tianxiang; WANG Lingyun; XU Xiping
2007-01-01
The system mathematical model of flexible 3D measuring system is built by theoretical analysis, and the theoretical formula for measuring space point coordinate is also derived.Frog-jumping based coordinate transform method is put forward in order to solve measuring problem for large size parts. The flog-jumping method is discussed, and the coordinate transform mathematical model is method of the space point coordinate compared to original value, and an advanced method is provided. Form the space point coordinate transform formula can derive the calculation measuring method for measuring large size parts.
Theoretical analysis of two ACO approaches for the traveling salesman problem
DEFF Research Database (Denmark)
Kötzing, Timo; Neumann, Frank; Röglin, Heiko
2012-01-01
Bioinspired algorithms, such as evolutionary algorithms and ant colony optimization, are widely used for different combinatorial optimization problems. These algorithms rely heavily on the use of randomness and are hard to understand from a theoretical point of view. This paper contributes...... to the theoretical analysis of ant colony optimization and studies this type of algorithm on one of the most prominent combinatorial optimization problems, namely the traveling salesperson problem (TSP). We present a new construction graph and show that it has a stronger local property than one commonly used...
Gene Knockout Identification Using an Extension of Bees Hill Flux Balance Analysis
Directory of Open Access Journals (Sweden)
Yee Wen Choon
2015-01-01
Full Text Available Microbial strain optimisation for the overproduction of a desired phenotype has been a popular topic in recent years. Gene knockout is a genetic engineering technique that can modify the metabolism of microbial cells to obtain desirable phenotypes. Optimisation algorithms have been developed to identify the effects of gene knockout. However, the complexities of metabolic networks have made the process of identifying the effects of genetic modification on desirable phenotypes challenging. Furthermore, a vast number of reactions in cellular metabolism often lead to a combinatorial problem in obtaining optimal gene knockout. The computational time increases exponentially as the size of the problem increases. This work reports an extension of Bees Hill Flux Balance Analysis (BHFBA to identify optimal gene knockouts to maximise the production yield of desired phenotypes while sustaining the growth rate. This proposed method functions by integrating OptKnock into BHFBA for validating the results automatically. The results show that the extension of BHFBA is suitable, reliable, and applicable in predicting gene knockout. Through several experiments conducted on Escherichia coli, Bacillus subtilis, and Clostridium thermocellum as model organisms, extension of BHFBA has shown better performance in terms of computational time, stability, growth rate, and production yield of desired phenotypes.
A review of ADM1 extensions, applications, and analysis 2002-2005
DEFF Research Database (Denmark)
Batstone, Damien J.; Keller, J.; Steyer, J.-P.
2006-01-01
hydrogen production from carbohydrate-type waste. Critical analysis of the model has mainly focused on model structure reduction, hydrogen inhibition functions, and the default parameter set recommended in the STIR. This default parameter set has largely been verified as a reasonable compromise, especially...... as a virtual industrial system can stimulate modelling of anaerobic processes by researchers and practitioners outside the core expertise of anaerobic processes. It has been used as a default structural element that allows researchers to concentrate on new extensions such,as sulfate reduction, and new...
Extensions to DSD theory: Analysis of PBX 9502 rate stick data
Energy Technology Data Exchange (ETDEWEB)
Aslam, T.D.; Bdzil, J.B.; Hill, L.G.
1998-12-31
Recent extensions to DSD theory and modeling argue that the intrinsic front propagation law can depend on variables in addition to the total shock-front curvature. Here the authors outline this work and present results of high-resolution numerical simulations of 2D detonation that verify the theory on some points, but disagree with it on others. Chief among these is the verification of the extended propagation laws and the observation that the curvature is infinite at the HE boundary. The authors discuss how these results impact the analysis of PBX 9502.
Spatio-temporal analysis of aftershock sequences in terms of Non Extensive Statistical Physics.
Chochlaki, Kalliopi; Vallianatos, Filippos
2017-04-01
Earth's seismicity is considered as an extremely complicated process where long-range interactions and fracturing exist (Vallianatos et al., 2016). For this reason, in order to analyze it, we use an innovative methodological approach, introduced by Tsallis (Tsallis, 1988; 2009), named Non Extensive Statistical Physics. This approach introduce a generalization of the Boltzmann-Gibbs statistical mechanics and it is based on the definition of Tsallis entropy Sq, which maximized leads the the so-called q-exponential function that expresses the probability distribution function that maximizes the Sq. In the present work, we utilize the concept of Non Extensive Statistical Physics in order to analyze the spatiotemporal properties of several aftershock series. Marekova (Marekova, 2014) suggested that the probability densities of the inter-event distances between successive aftershocks follow a beta distribution. Using the same data set we analyze the inter-event distance distribution of several aftershocks sequences in different geographic regions by calculating non extensive parameters that determine the behavior of the system and by fitting the q-exponential function, which expresses the degree of non-extentivity of the investigated system. Furthermore, the inter-event times distribution of the aftershocks as well as the frequency-magnitude distribution has been analyzed. The results supports the applicability of Non Extensive Statistical Physics ideas in aftershock sequences where a strong correlation exists along with memory effects. References C. Tsallis, Possible generalization of Boltzmann-Gibbs statistics, J. Stat. Phys. 52 (1988) 479-487. doi:10.1007/BF01016429 C. Tsallis, Introduction to nonextensive statistical mechanics: Approaching a complex world, 2009. doi:10.1007/978-0-387-85359-8. E. Marekova, Analysis of the spatial distribution between successive earthquakes in aftershocks series, Annals of Geophysics, 57, 5, doi:10.4401/ag-6556, 2014 F. Vallianatos, G
Directory of Open Access Journals (Sweden)
Sergey Uzhegov
2011-09-01
Full Text Available The current study examines how analysis of the Phenomenon of Plenty, paradox of economic underperformance of resource-rich nations, could benefit from theoretical and empirical application of suggested petroleum production function framework, basing on sample oil-abundant countries of the Commonwealth of Independent States, in particular Russia, Azerbaijan, and Kazakhstan. Proposed approach displays capacity of oil-economy production function to shed light on larger scope of theoretical issues. Empirical testing of suggested theoretical framework exhibited ability of proxied components of devised production function, capturing main metrics of the Phenomenon of Plenty and additionally factoring in corruption, to exert a strong impact on the majority of twelve principal macroeconomic indicators monitored by CIS supra-national institutions: with most pronounced influence on gross domestic product, industrial production, capital investments, and export to CIS countries.
Institute of Scientific and Technical Information of China (English)
无
2010-01-01
The essential requirements for evaluating the sustainable development of a system and the thermodynamic framework of the energy conservation mechanism in the waste-removal process are proposed.A thermodynamic method of analysis based on the first and second laws of thermodynamics is suggested as a means to analyze the theoretical energy consumption for the removal of organic contaminants by physical methods.Moreover,the theoretical energy consumption for the removal by physical methods of different kinds of representative organic contaminants with different initial concentrations and amounts is investigated at 298.15 K and 1.01325 × 105 Pa.The results show that the waste treatment process has a high energy consumption and that the theoretical energy consumption for the removal of organic contaminants increases with the decrease of their initial concentrations in aqueous solutions.The theoretical energy consumption for the removal of different organic contaminants varies dramatically.Furthermore,the theoretical energy consumption increases greatly with the increase in the amount to be removed.
Directory of Open Access Journals (Sweden)
Stefanik A.
2015-06-01
Full Text Available Technology of round bars rolling on a three-high skew rolling mills allows rolling of standard materials such as steel and aluminum, as well as new materials, especially hard deformable materials. The paper presents the results of theoretical and experimental rolling process of aluminum bars with a diameter of 20 mm. As the stock round bars with a diameter of 25 mm made of aluminum grade 1050A and aluminum alloy grade 2017A were used. The rolling process of aluminum bars has been carried out in a single pass. The numerical analysis was carried out by using computer program Forge2011®. On the basis of theoretical research it has been determined the state of deformation, stress and temperature distribution during rolling of aluminum bars. In addition, the results of theoretical research allowed to determine the schema of the metal plastic flow in the roll gap. Verification of the theoretical research was carried out during the rolling of aluminum bars on the RSP 40/14 laboratory three-high skew rolling mill. From the finished bars were taken the samples to set the shape and compared with the results of theoretical research. Finished aluminum round bars were characterized by low ovality and good surface quality.
Directory of Open Access Journals (Sweden)
Nakayama Shinsuke
2017-01-01
Full Text Available We have developed an integrated code system dedicated for theoretical analysis and prediction of deuteron-induced reactions, which is called DEUteron-induced Reaction Analysis Code System (DEURACS. DEURACS consists of several calculation codes based on theoretical models to describe respective reaction mechanisms and it was successfully applied to (d,xp and (d,xn reactions. In the present work, the analysis of (d,xn reactions is extended to higher incident energy up to nearly 100 MeV and also DEURACS is applied to (d,xd reactions at 80 and 100 MeV. The DEURACS calculations reproduce the experimental double-differential cross sections for the (d,xn and (d,xd reactions well.
Directory of Open Access Journals (Sweden)
Hadeed A. Sher
2017-04-01
Full Text Available In this paper theoretical and experimental analysis of an AC–DC–AC inverter under DC link capacitor failure is presented. The failure study conducted for this paper is the open circuit of the DC link capacitor. The presented analysis incorporates the results for both single and three phase AC input. It has been observed that the higher ripple frequency provides better ride through capability for this fault. Furthermore, the effects of this fault on electrical characteristics of AC–DC–AC inverter and mechanical properties of the induction motor are also presented. Moreover, the effect of pulsating torque as a result of an open circuited DC link capacitor is also taken into consideration. Theoretical analysis is supported by computer aided simulation as well as with a real time experimental prototype.
Nakayama, Shinsuke; Kouno, Hiroshi; Watanabe, Yukinobu; Iwamoto, Osamu; Ye, Tao; Ogata, Kazuyuki
2017-09-01
We have developed an integrated code system dedicated for theoretical analysis and prediction of deuteron-induced reactions, which is called DEUteron-induced Reaction Analysis Code System (DEURACS). DEURACS consists of several calculation codes based on theoretical models to describe respective reaction mechanisms and it was successfully applied to (d,xp) and (d,xn) reactions. In the present work, the analysis of (d,xn) reactions is extended to higher incident energy up to nearly 100 MeV and also DEURACS is applied to (d,xd) reactions at 80 and 100 MeV. The DEURACS calculations reproduce the experimental double-differential cross sections for the (d,xn) and (d,xd) reactions well.
Mayorga-Vega, Daniel; Merino-Marban, Rafael; Viciana, Jesús
2014-01-01
The main purpose of the present meta-analysis was to examine the scientific literature on the criterion-related validity of sit-and-reach tests for estimating hamstring and lumbar extensibility. For this purpose relevant studies were searched from seven electronic databases dated up through December 2012. Primary outcomes of criterion-related validity were Pearson´s zero-order correlation coefficients (r) between sit-and-reach tests and hamstrings and/or lumbar extensibility criterion measures. Then, from the included studies, the Hunter- Schmidt´s psychometric meta-analysis approach was conducted to estimate population criterion- related validity of sit-and-reach tests. Firstly, the corrected correlation mean (rp), unaffected by statistical artefacts (i.e., sampling error and measurement error), was calculated separately for each sit-and-reach test. Subsequently, the three potential moderator variables (sex of participants, age of participants, and level of hamstring extensibility) were examined by a partially hierarchical analysis. Of the 34 studies included in the present meta-analysis, 99 correlations values across eight sit-and-reach tests and 51 across seven sit-and-reach tests were retrieved for hamstring and lumbar extensibility, respectively. The overall results showed that all sit-and-reach tests had a moderate mean criterion-related validity for estimating hamstring extensibility (rp = 0.46-0.67), but they had a low mean for estimating lumbar extensibility (rp = 0. 16-0.35). Generally, females, adults and participants with high levels of hamstring extensibility tended to have greater mean values of criterion-related validity for estimating hamstring extensibility. When the use of angular tests is limited such as in a school setting or in large scale studies, scientists and practitioners could use the sit-and-reach tests as a useful alternative for hamstring extensibility estimation, but not for estimating lumbar extensibility. Key PointsOverall sit
A study and extension of second-order blind source separation to operational modal analysis
Antoni, J.; Chauhan, S.
2013-02-01
Second-order blind source separation (SOBSS) has gained recent interest in operational modal analysis (OMA), since it is able to separate a set of system responses into modal coordinates from which the system poles can be extracted by single-degree-of-freedom techniques. In addition, SOBSS returns a mixing matrix whose columns are the estimates of the system mode shapes. The objective of this paper is threefold. First, a theoretical analysis of current SOBSS methods is conducted within the OMA framework and its precise conditions of applicability are established. Second, a new separation method is proposed that fixes current limitations of SOBSS: It returns estimate of complex mode shapes, it can deal with more active modes than the number of available sensors, and it shows superior performance in the case of heavily damped and/or strongly coupled modes. Third, a theoretical connection is drawn between SOBSS and stochastic subspace identification (SSI), which stands as one of the points of reference in OMA. All approaches are finally compared by means of numerical simulations.
Directory of Open Access Journals (Sweden)
Aitman T
2008-11-01
Full Text Available Abstract Background Microarray experimentation requires the application of complex analysis methods as well as the use of non-trivial computer technologies to manage the resultant large data sets. This, together with the proliferation of tools and techniques for microarray data analysis, makes it very challenging for a laboratory scientist to keep up-to-date with the latest developments in this field. Our aim was to develop a distributed e-support system for microarray data analysis and management. Results EMAAS (Extensible MicroArray Analysis System is a multi-user rich internet application (RIA providing simple, robust access to up-to-date resources for microarray data storage and analysis, combined with integrated tools to optimise real time user support and training. The system leverages the power of distributed computing to perform microarray analyses, and provides seamless access to resources located at various remote facilities. The EMAAS framework allows users to import microarray data from several sources to an underlying database, to pre-process, quality assess and analyse the data, to perform functional analyses, and to track data analysis steps, all through a single easy to use web portal. This interface offers distance support to users both in the form of video tutorials and via live screen feeds using the web conferencing tool EVO. A number of analysis packages, including R-Bioconductor and Affymetrix Power Tools have been integrated on the server side and are available programmatically through the Postgres-PLR library or on grid compute clusters. Integrated distributed resources include the functional annotation tool DAVID, GeneCards and the microarray data repositories GEO, CELSIUS and MiMiR. EMAAS currently supports analysis of Affymetrix 3' and Exon expression arrays, and the system is extensible to cater for other microarray and transcriptomic platforms. Conclusion EMAAS enables users to track and perform microarray data
Sundarraj, Pradeepkumar; Taylor, Robert A.; Banerjee, Debosmita; Maity, Dipak; Sinha Roy, Susanta
2017-01-01
Hybrid solar thermoelectric generators (HSTEGs) have garnered significant research attention recently due to their potential ability to cogenerate heat and electricity. In this paper, theoretical and experimental investigations of the electrical and thermal performance of a HSTEG system are reported. In order to validate the theoretical model, a laboratory scale HSTEG system (based on forced convection cooling) is developed. The HSTEG consists of six thermoelectric generator modules, an electrical heater, and a stainless steel cooling block. Our experimental analysis shows that the HSTEG is capable of producing a maximum electrical power output of 4.7 W, an electrical efficiency of 1.2% and thermal efficiency of 61% for an average temperature difference of 92 °C across the TEG modules with a heater power input of 382 W. These experimental results of the HSTEG system are found to be in good agreement with the theoretical prediction. This experimental/theoretical analysis can also serve as a guide for evaluating the performance of the HSTEG system with forced convection cooling.
Totaro, N.; Guyader, J. L.
2012-06-01
The present article deals with an extension of the Statistical modal Energy distribution Analysis (SmEdA) method to estimate kinetic and potential energy density in coupled subsystems. The SmEdA method uses the modal bases of uncoupled subsystems and focuses on the modal energies rather than the global energies of subsystems such as SEA (Statistical Energy Analysis). This method permits extending SEA to subsystems with low modal overlap or to localized excitations as it does not assume the existence of modal energy equipartition. We demonstrate that by using the modal energies of subsystems computed by SmEdA, it is possible to estimate energy distribution in subsystems. This approach has the same advantages of standard SEA, as it uses very short calculations to analyze damping effects. The estimation of energy distribution from SmEdA is applied to an academic case and an industrial example.
1979-01-01
to motivate the form of the results for inelastic binary collisions characterized by an isotropic scattering cross section. For an inelastic...which are excited or ionized by the e -beam . Strictly speaking , the reverse process for reaction (101. 1) should also be included, although its...ETC F/S 20/5 THEORETICAL MODELING OF MOLECULAR AND ELECTRON KINETIC PROCESS~— efl ~ (rj)JAN 79 W B LACINA NO OO i~—78—C—Ofl9UNCLASSIFIED NRTC—79—7R
Kolokoltsov, Vassili
2011-01-01
Expanding the ideas of the author's paper 'Nonexpansive maps and option pricing theory' (Kibernetica 34:6 (1998), 713-724) we develop a pure game-theoretic approach to option pricing, by-passing stochastic modeling. Risk neutral probabilities emerge automatically from the robust control evaluation. This approach seems to be especially appealing for incomplete markets encompassing extensive, so to say untamed, randomness, when the coexistence of infinite number of risk neutral measures precludes one from unified pricing of derivative securities. Our method is robust enough to be able to accommodate various markets rules and settings including path dependent payoffs, American options and transaction costs. On the other hand, it leads to rather simple numerical algorithms. Continuous time limit is described by nonlinear and/or fractional Black-Scholes type equations.
Francesco Negro; Ş Utku Yavuz; Dario Farina
2014-01-01
Contractile properties of human motor units provide information on the force capacity and fatigability of muscles. The spike-triggered averaging technique (STA) is a conventional method used to estimate the twitch waveform of single motor units in vivo by averaging the joint force signal. Several limitations of this technique have been previously discussed in an empirical way, using simulated and experimental data. In this study, we provide a theoretical analysis of this technique in the freq...
Davidović Nebojša; Bonić Zoran; Prolović Verka; Mladenović Biljana; Stojić Dragoslav
2010-01-01
The paper presents a brief description of experiment within the research project 'Theoretical and experimental analysis of interaction of shallow reinforced concrete foundations and soil for the purpose of improvement of national regulations and implementaation of Eurocode system' where in situ tests of a series of reinforced concrete foundation footing were performed, by loading until failure. As a rule, methods for calculation of shallow foundations settlement on granular soils overestimate...
Can Computer-Mediated Interventions Change Theoretical Mediators of Safer Sex? A Meta-Analysis
Noar, Seth M.; Pierce, Larson B.; Black, Hulda G.
2010-01-01
The purpose of this study was to conduct a meta-analysis of computer-mediated interventions (CMIs) aimed at changing theoretical mediators of safer sex. Meta-analytic aggregation of effect sizes from k = 20 studies indicated that CMIs significantly improved HIV/AIDS knowledge, d = 0.276, p less than 0.001, k = 15, N = 6,625; sexual/condom…
Weeds: a CLASS extension for the analysis of millimeter and sub-millimeter spectral surveys
Maret, S; Pety, J; Bardeau, S; Reynier, E
2010-01-01
The advent of large instantaneous bandwidth receivers and high spectral resolution spectrometers on (sub-)millimeter telescopes has opened up the possibilities for unbiased spectral surveys. Because of the large amount of data they contain, any analysis of these surveys requires dedicated software tools. Here we present an extension of the widely used CLASS software that we developed to that purpose. This extension, named Weeds, allows for searches in atomic and molecular lines databases (e.g. JPL or CDMS) that may be accessed over the internet using a virtual observatory (VO) compliant protocol. The package permits a quick navigation across a spectral survey to search for lines of a given species. Weeds is also capable of modeling a spectrum, as often needed for line identification. We expect that Weeds will be useful for analyzing and interpreting the spectral surveys that will be done with the HIFI instrument on board Herschel, but also observations carried-out with ground based millimeter and sub-millimet...
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Mahshid Bahadori
2016-03-01
Full Text Available The purpose of this research is to do a meta-analysis of studies about the results of researches conducted related to the factors affecting the occupational and professionalism performance in the field of agricultural extension agents, in order to integrate the results of research independently carried out to obtain more accurate and more cohesive results. In order to achieve the goal, 177 researches made on the occupational and professional performance (occupational performance, professional performance, professional competence, professional developmentwere collected from sites magiran & sid, and among them, 10 research were selected utilizing tools "check list of technical and methodological research" (including appropriate reliability and validity statistical and sampling correct methodto review and metaanalysis. The results showed that professional features have the greatest impact on the professional and occupational performance of agricultural extension agents. As well, skills and technical competence, the number of field visits, membership of organizations, participation in in-service training courses and access to educational facilities have a high impact on occupational and professional performance. The researchers confirmed these results.
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Daniel Mayorga-Vega
2014-03-01
Full Text Available The main purpose of the present meta-analysis was to examine the scientific literature on the criterion-related validity of sit-and-reach tests for estimating hamstring and lumbar extensibility. For this purpose relevant studies were searched from seven electronic databases dated up through December 2012. Primary outcomes of criterion-related validity were Pearson´s zero-order correlation coefficients (r between sit-and-reach tests and hamstrings and/or lumbar extensibility criterion measures. Then, from the included studies, the Hunter- Schmidt´s psychometric meta-analysis approach was conducted to estimate population criterion- related validity of sit-and-reach tests. Firstly, the corrected correlation mean (rp, unaffected by statistical artefacts (i.e., sampling error and measurement error, was calculated separately for each sit-and-reach test. Subsequently, the three potential moderator variables (sex of participants, age of participants, and level of hamstring extensibility were examined by a partially hierarchical analysis. Of the 34 studies included in the present meta-analysis, 99 correlations values across eight sit-and-reach tests and 51 across seven sit-and-reach tests were retrieved for hamstring and lumbar extensibility, respectively. The overall results showed that all sit-and-reach tests had a moderate mean criterion-related validity for estimating hamstring extensibility (rp = 0.46-0.67, but they had a low mean for estimating lumbar extensibility (rp = 0. 16-0.35. Generally, females, adults and participants with high levels of hamstring extensibility tended to have greater mean values of criterion-related validity for estimating hamstring extensibility. When the use of angular tests is limited such as in a school setting or in large scale studies, scientists and practitioners could use the sit-and-reach tests as a useful alternative for hamstring extensibility estimation, but not for estimating lumbar extensibility.
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.
A theoretical analysis of the reaction between ethyl and molecular oxygen
Energy Technology Data Exchange (ETDEWEB)
James A. Miller; Stephen J. Klippenstein; Stuart H. Robertson
2000-12-13
Using a combination of electronic-structure theory, variational transition-state theory, and solutions to the time-dependent master equation, the authors have studied the kinetics of the title reaction theoretically over wide ranges of temperature and pressure. The agreement between theory and experiment is quite good. By comparing the theoretical and experimental results describing the kinetic behavior, they have been able to deduce a value for the C{sub 2}H{sub 5}-O{sub 2} bond energy of {approximately}34 kcal/mole and a value for the exit-channel transition-state energy of {minus}4.3 kcal/mole (measured from reactants). These numbers compare favorably with the electronic-structure theory predictions of 33.9 kcal/mole and {minus}3.0 kcal/mole, respectively. The master-equation solutions show three distinct temperature regimes for the reaction, discussed extensively in the paper. Above T {approx} 700 K, the reaction can be written as an elementary step, C{sub 2}H{sub 5} + O{sub 2} {leftrightarrow} C{sub 2}H{sub 4} + HO{sub 2}, with the rate coefficient, k(T) = 3.19 x 10{sup {minus}17} T{sup 1.02} exp(2035/RT) cm{sup 3}/molec.-sec., independent of pressure even though the intermediate collision complex may suffer a large number of collisions.
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Gian Matteo Rigolin
2016-09-01
Full Text Available Abstract Background In chronic lymphocytic leukemia (CLL, next-generation sequencing (NGS analysis represents a sensitive, reproducible, and resource-efficient technique for routine screening of gene mutations. Methods We performed an extensive biologic characterization of newly diagnosed CLL, including NGS analysis of 20 genes frequently mutated in CLL and karyotype analysis to assess whether NGS and karyotype results could be of clinical relevance in the refinement of prognosis and assessment of risk of progression. The genomic DNA from peripheral blood samples of 200 consecutive CLL patients was analyzed using Ion Torrent Personal Genome Machine, a NGS platform that uses semiconductor sequencing technology. Karyotype analysis was performed using efficient mitogens. Results Mutations were detected in 42.0 % of cases with 42.8 % of mutated patients presenting 2 or more mutations. The presence of mutations by NGS was associated with unmutated IGHV gene (p = 0.009, CD38 positivity (p = 0.010, risk stratification by fluorescence in situ hybridization (FISH (p < 0.001, and the complex karyotype (p = 0.003. A high risk as assessed by FISH analysis was associated with mutations affecting TP53 (p = 0.012, BIRC3 (p = 0.003, and FBXW7 (p = 0.003 while the complex karyotype was significantly associated with TP53, ATM, and MYD88 mutations (p = 0.003, 0.018, and 0.001, respectively. By multivariate analysis, the multi-hit profile (≥2 mutations by NGS was independently associated with a shorter time to first treatment (p = 0.004 along with TP53 disruption (p = 0.040, IGHV unmutated status (p < 0.001, and advanced stage (p < 0.001. Advanced stage (p = 0.010, TP53 disruption (p < 0.001, IGHV unmutated status (p = 0.020, and the complex karyotype (p = 0.007 were independently associated with a shorter overall survival. Conclusions At diagnosis, an extensive biologic characterization including
THEORETICAL AND METHODOLOGICAL PRINCIPLES OF THE STRATEGIC FINANCIAL ANALYSIS OF CAPITAL
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Olha KHUDYK
2016-07-01
Full Text Available The article is devoted to the theoretical and methodological principles of strategic financial analysis of capital. The necessity of strategic financial analysis of capital as a methodological basis for study strategies is proved in modern conditions of a high level of dynamism, uncertainty and risk. The methodological elements of the strategic financial analysis of capital (the object of investigation, the indicators, the factors, the methods of study, the subjects of analysis, the sources of incoming and outgoing information are justified in the system of financial management, allowing to improve its theoretical foundations. It is proved that the strategic financial analysis of capital is a continuous process, carried out in an appropriate sequence at each stage of capital circulation. The system of indexes is substantiated, based on the needs of the strategic financial analysis. The classification of factors determining the size and structure of company’s capital is grounded. The economic nature of capital of the company is clarified. We consider that capital is a stock of economic resources in the form of cash, tangible and intangible assets accumulated by savings, which is used by its owner as a factor of production and investment resource in the economic process in order to obtain profit, to ensure the growth of owners’ prosperity and to achieve social effect.
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Tsalatsanis Athanasios
2011-12-01
Full Text Available Abstract Background Despite the well documented advantages of hospice care, most terminally ill patients do not reap the maximum benefit from hospice services, with the majority of them receiving hospice care either prematurely or delayed. Decision systems to improve the hospice referral process are sorely needed. Methods We present a novel theoretical framework that is based on well-established methodologies of prognostication and decision analysis to assist with the hospice referral process for terminally ill patients. We linked the SUPPORT statistical model, widely regarded as one of the most accurate models for prognostication of terminally ill patients, with the recently developed regret based decision curve analysis (regret DCA. We extend the regret DCA methodology to consider harms associated with the prognostication test as well as harms and effects of the management strategies. In order to enable patients and physicians in making these complex decisions in real-time, we developed an easily accessible web-based decision support system available at the point of care. Results The web-based decision support system facilitates the hospice referral process in three steps. First, the patient or surrogate is interviewed to elicit his/her personal preferences regarding the continuation of life-sustaining treatment vs. palliative care. Then, regret DCA is employed to identify the best strategy for the particular patient in terms of threshold probability at which he/she is indifferent between continuation of treatment and of hospice referral. Finally, if necessary, the probabilities of survival and death for the particular patient are computed based on the SUPPORT prognostication model and contrasted with the patient's threshold probability. The web-based design of the CDSS enables patients, physicians, and family members to participate in the decision process from anywhere internet access is available. Conclusions We present a theoretical
Pagliaro, Antonio; D'Alí Staiti, G.; D'Anna, F.
2011-03-01
We present a new method for the identification of extensive air showers initiated by different primaries. The method uses the multiscale concept and is based on the analysis of multifractal behaviour and lacunarity of secondary particle distributions together with a properly designed and trained artificial neural network. In the present work the method is discussed and applied to a set of fully simulated vertical showers, in the experimental framework of ARGO-YBJ, to obtain hadron to gamma primary separation. We show that the presented approach gives very good results, leading, in the 1-10 TeV energy range, to a clear improvement of the discrimination power with respect to the existing figures for extended shower detectors.
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Pagliaro, Antonio, E-mail: pagliaro@ifc.inaf.it [Istituto di Astrofisica Spaziale e Fisica Cosmica di Palermo - Istituto Nazionale di Astrofisica, Via Ugo La Malfa 153, 90146 Palermo (Italy); Istituto Nazionale di Fisica Nucleare, Sezione di Catania, Viale A. Doria 6, 95125 Catania (Italy); D' Ali Staiti, G. [Universita degli Studi di Palermo, Dipartimento di Fisica e Tecnologie Relative, Viale delle Scienze, Edificio 18, 90128 Palermo (Italy); Istituto Nazionale di Fisica Nucleare, Sezione di Catania, Viale A. Doria 6, 95125 Catania (Italy); D' Anna, F. [Istituto di Astrofisica Spaziale e Fisica Cosmica di Palermo - Istituto Nazionale di Astrofisica, Via Ugo La Malfa 153, 90146 Palermo (Italy)
2011-03-15
We present a new method for the identification of extensive air showers initiated by different primaries. The method uses the multiscale concept and is based on the analysis of multifractal behaviour and lacunarity of secondary particle distributions together with a properly designed and trained artificial neural network. In the present work the method is discussed and applied to a set of fully simulated vertical showers, in the experimental framework of ARGO-YBJ, to obtain hadron to gamma primary separation. We show that the presented approach gives very good results, leading, in the 1-10 TeV energy range, to a clear improvement of the discrimination power with respect to the existing figures for extended shower detectors.
Project Milestone. Analysis of Range Extension Techniques for Battery Electric Vehicles
Energy Technology Data Exchange (ETDEWEB)
Neubauer, Jeremy [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Wood, Eric [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Pesaran, Ahmad [National Renewable Energy Laboratory (NREL), Golden, CO (United States)
2013-07-01
This report documents completion of the July 2013 milestone as part of NREL’s Vehicle Technologies Annual Operating Plan with the U.S. Department of Energy. The objective was to perform analysis on range extension techniques for battery electric vehicles (BEVs). This work represents a significant advancement over previous thru-life BEV analyses using NREL’s Battery Ownership Model, FastSim,* and DRIVE.* Herein, the ability of different charging infrastructure to increase achievable travel of BEVs in response to real-world, year-long travel histories is assessed. Effects of battery and cabin thermal response to local climate, battery degradation, and vehicle auxiliary loads are captured. The results reveal the conditions under which different public infrastructure options are most effective, and encourage continued study of fast charging and electric roadway scenarios.
A non-iterative extension of the multivariate random effects meta-analysis.
Makambi, Kepher H; Seung, Hyunuk
2015-01-01
Multivariate methods in meta-analysis are becoming popular and more accepted in biomedical research despite computational issues in some of the techniques. A number of approaches, both iterative and non-iterative, have been proposed including the multivariate DerSimonian and Laird method by Jackson et al. (2010), which is non-iterative. In this study, we propose an extension of the method by Hartung and Makambi (2002) and Makambi (2001) to multivariate situations. A comparison of the bias and mean square error from a simulation study indicates that, in some circumstances, the proposed approach perform better than the multivariate DerSimonian-Laird approach. An example is presented to demonstrate the application of the proposed approach.
An extensive analysis of the parity of broken 3-diamond partitions.
Radu, Silviu; Sellers, James A
2013-11-01
In 2007, Andrews and Paule introduced the family of functions [Formula: see text] which enumerate the number of broken k-diamond partitions for a fixed positive integer k. Since then, numerous mathematicians have considered partitions congruences satisfied by [Formula: see text] for small values of k. In this work, we provide an extensive analysis of the parity of the function [Formula: see text], including a number of Ramanujan-like congruences modulo 2. This will be accomplished by completely characterizing the values of [Formula: see text] modulo 2 for [Formula: see text] and any value of [Formula: see text]. In contrast, we conjecture that, for any integers [Formula: see text], [Formula: see text] and [Formula: see text] is infinitely often even and infinitely often odd. In this sense, we generalize Subbarao's Conjecture for this function [Formula: see text]. To the best of our knowledge, this is the first generalization of Subbarao's Conjecture in the literature.
Hsu, Anne S.; Chater, Nick; Vitanyi, Paul M. B.
2011-01-01
There is much debate over the degree to which language learning is governed by innate language-specific biases, or acquired through cognition-general principles. Here we examine the probabilistic language acquisition hypothesis on three levels: We outline a novel theoretical result showing that it is possible to learn the exact "generative model"…
Blade loss transient dynamics analysis, volume 1. Task 2: TETRA 2 theoretical development
Gallardo, Vincente C.; Black, Gerald
1986-01-01
The theoretical development of the forced steady state analysis of the structural dynamic response of a turbine engine having nonlinear connecting elements is discussed. Based on modal synthesis, and the principle of harmonic balance, the governing relations are the compatibility of displacements at the nonlinear connecting elements. There are four displacement compatibility equations at each nonlinear connection, which are solved by iteration for the principle harmonic of the excitation frequency. The resulting computer program, TETRA 2, combines the original TETRA transient analysis (with flexible bladed disk) with the steady state capability. A more versatile nonlinear rub or bearing element which contains a hardening (or softening) spring, with or without deadband, is also incorporated.
IQM: an extensible and portable open source application for image and signal analysis in Java.
Kainz, Philipp; Mayrhofer-Reinhartshuber, Michael; Ahammer, Helmut
2015-01-01
Image and signal analysis applications are substantial in scientific research. Both open source and commercial packages provide a wide range of functions for image and signal analysis, which are sometimes supported very well by the communities in the corresponding fields. Commercial software packages have the major drawback of being expensive and having undisclosed source code, which hampers extending the functionality if there is no plugin interface or similar option available. However, both variants cannot cover all possible use cases and sometimes custom developments are unavoidable, requiring open source applications. In this paper we describe IQM, a completely free, portable and open source (GNU GPLv3) image and signal analysis application written in pure Java. IQM does not depend on any natively installed libraries and is therefore runnable out-of-the-box. Currently, a continuously growing repertoire of 50 image and 16 signal analysis algorithms is provided. The modular functional architecture based on the three-tier model is described along the most important functionality. Extensibility is achieved using operator plugins, and the development of more complex workflows is provided by a Groovy script interface to the JVM. We demonstrate IQM's image and signal processing capabilities in a proof-of-principle analysis and provide example implementations to illustrate the plugin framework and the scripting interface. IQM integrates with the popular ImageJ image processing software and is aiming at complementing functionality rather than competing with existing open source software. Machine learning can be integrated into more complex algorithms via the WEKA software package as well, enabling the development of transparent and robust methods for image and signal analysis.
IQM: an extensible and portable open source application for image and signal analysis in Java.
Directory of Open Access Journals (Sweden)
Philipp Kainz
Full Text Available Image and signal analysis applications are substantial in scientific research. Both open source and commercial packages provide a wide range of functions for image and signal analysis, which are sometimes supported very well by the communities in the corresponding fields. Commercial software packages have the major drawback of being expensive and having undisclosed source code, which hampers extending the functionality if there is no plugin interface or similar option available. However, both variants cannot cover all possible use cases and sometimes custom developments are unavoidable, requiring open source applications. In this paper we describe IQM, a completely free, portable and open source (GNU GPLv3 image and signal analysis application written in pure Java. IQM does not depend on any natively installed libraries and is therefore runnable out-of-the-box. Currently, a continuously growing repertoire of 50 image and 16 signal analysis algorithms is provided. The modular functional architecture based on the three-tier model is described along the most important functionality. Extensibility is achieved using operator plugins, and the development of more complex workflows is provided by a Groovy script interface to the JVM. We demonstrate IQM's image and signal processing capabilities in a proof-of-principle analysis and provide example implementations to illustrate the plugin framework and the scripting interface. IQM integrates with the popular ImageJ image processing software and is aiming at complementing functionality rather than competing with existing open source software. Machine learning can be integrated into more complex algorithms via the WEKA software package as well, enabling the development of transparent and robust methods for image and signal analysis.
A Discrete Event Simulator for Extensive Defense Mechanism for Denial of Service Attacks Analysis
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Maryam Tanha
2012-01-01
Full Text Available Problem statement: Seeking for defense mechanisms against low rate Denial of Service (DoS attacks as a new generation of DoS attacks has received special attention during recent years. As a decisive factor, evaluating the performance of the offered mitigation techniques based on different metrics for determining the viability and ability of these countermeasures requires more research. Approach: The development of a new generalized discrete event simulator has been deliberated in detail. The research conducted places high emphasis on the benefits of creating a customized discrete event simulator for the analysis of security and in particular the DoS attacks. The simulator possesses a niche in terms of the small scale, low execution time, portability and ease of use. The attributes and mechanism of the developed simulator is complemented with the proposed framework. Results: The simulator has been extensively evaluated and has proven to provide an ideal tool for the analysis and exploration of DoS attacks. In-depth analysis is enabled by this simulator for creating multitudes of defense mechanisms against HTTP low rate DoS attacks. The acquired results from the simulation tool have been compared against a simulator from the same domain. Subsequently, it enables the validation of developed simulator utilizing selected performance metrics including mean in-system time, average delay and average buffer size. Conclusion: The proposed simulator serves as an efficient and scalable performance analysis tool for the analysis of HTTP low rate DoS attack defense mechanism. Future work can encompass the development of discrete event simulators for analysis of other security issues such as Intrusion Detection Systems.
First, Leili K.
This dissertation investigates the intersections and interactions of factors which enhance and inhibit creativity in theoretical physics research, using a situational analysis of the fifth Solvay Council on Physics of 1927 (Solvay 1927), a pivotal point in the history of quantum physics. Situational analysis is a postmodern variant of the grounded theory method which views a situation as the unit of analysis and adds situational mapping as an analytic tool. This method specifically works against normalizing or simplifying the points of view, instead drawing out diversity, complexity, and contradiction. It results in "theorizing" rather than theory. This research differs from other analyses of the development of quantum mechanics in looking at technical issues as well as individual, collective, and societal factors. Data examined in this historical analysis includes theoretical papers, conference proceedings, personal letters, and commentary and analysis, both contemporaneous and modern. Literature related to scientific creativity was also consulted. Mapping the situation as a master discourse of Niels Bohr overlapping and interacting with co-existent major discourses on matrix mechanics/Copenhagen interpretation, wave mechanics, and the pilot-wave theory resulted in the most descriptive illustration of the factors influencing scientific creativity before and after Solvay 1927. The master discourse strongly influenced the major discourses and generated the "Copenhagen spirit" which effectively marginalized discourses other than matrix mechanics/Copenhagen interpretation after Solvay 1927.
THEORETICAL AND METHODOLOGICAL PRINCIPLES OF THE STRATEGIC FINANCIAL ANALYSIS OF CAPITAL
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Olha KHUDYK
2016-07-01
Full Text Available The article is devoted to the theoretical and methodological principles of strategic financial analysis of capital. The necessity of strategic financial analysis of capital as a methodological basis for study strategies is proved in modern conditions of a high level of dynamism, uncertainty and risk. The methodological elements of the strategic indicators, the factors, the methods of study, the subjects of analysis, the sources of incoming and outgoing information are justified in the system of financial management, allowing to improve its theoretical foundations. It is proved that the strategic financial analysis of capital is a continuous process, carried out in an appropriate sequence at each stage of capital circulation. The system of indexes is substantiated, based on the needs of the strategic financial analysis. The classification of factors determining the size and structure of company’s capital is grounded. The economic nature of capital of the company is clarified. We consider that capital is a stock of economic resources in the form of cash, tangible and intangible assets accumulated by savings, which is used by its owner as a factor of production and investment resource in the economic process in order to obtain profit, to ensure the growth of owners’ prosperity and to achieve social effect.
Asynchronous cellular automaton-based neuron: theoretical analysis and on-FPGA learning.
Matsubara, Takashi; Torikai, Hiroyuki
2013-05-01
A generalized asynchronous cellular automaton-based neuron model is a special kind of cellular automaton that is designed to mimic the nonlinear dynamics of neurons. The model can be implemented as an asynchronous sequential logic circuit and its control parameter is the pattern of wires among the circuit elements that is adjustable after implementation in a field-programmable gate array (FPGA) device. In this paper, a novel theoretical analysis method for the model is presented. Using this method, stabilities of neuron-like orbits and occurrence mechanisms of neuron-like bifurcations of the model are clarified theoretically. Also, a novel learning algorithm for the model is presented. An equivalent experiment shows that an FPGA-implemented learning algorithm enables an FPGA-implemented model to automatically reproduce typical nonlinear responses and occurrence mechanisms observed in biological and model neurons.
Institute of Scientific and Technical Information of China (English)
Shoufu LI
2009-01-01
In this review,we present the recent work of the author in comparison with various related results obtained by other authors in literature.We first recall the stability,contractivity and asymptotic stability results of the true solution to nonlinear stiff Volterra functional differential equations (VFDEs),then a series of stability,contractivity,asymptotic stability and B-convergence results of Runge-Kutta methods for VFDEs is presented in detail.This work provides a unified theoretical foundation for the theoretical and numerical analysis of nonlinear stiff problems in delay differential equations (DDEs),integro-differential equations (IDEs),delayintegro-differential equations (DIDEs) and VFDEs of other type which appear in practice.
Buchner, Teodor; Gielerak, Grzegorz
2010-01-01
Using a three-compartment model of blood pressure dynamics, we analyze theoretically the short term cardiovascular variability: how the respiratory-related blood pressure fluctuations are buffered by appropriate heart rate changes: i.e. the respiratory sinus arrhythmia. The buffering is shown to be crucially dependent on the time delay between the stimulus (such as e.g. the inspiration onset) and the application of the control (the moment in time when the efferent response is delivered to the heart). This theoretical analysis shows that the buffering mechanism is effective only in the upright position of the body. It explains a paradoxical effect of enhancement of the blood pressure fluctuations by an ineffective control. Such a phenomenon was observed experimentally. Using the basis of the model, we discuss the blood pressure variability and heart rate variability under such clinical conditions as the states of expressed adrenergic drive and the tilt-test during the parasympathetic blockade or fixed rate atr...
Experimental and theoretical oscillator strengths of Mg i for accurate abundance analysis
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.
Matsumura, Masashi; Ichikawa, Kazuna; Takei, Hitoshi
2017-01-01
This study attempted to develop a formula for predicting maximum muscle strength value for young, middle-aged, and elderly adults using theoretical Grade 3 muscle strength value (moment fair: Mf)—the static muscular moment to support a limb segment against gravity—from the manual muscle test by Daniels et al. A total of 130 healthy Japanese individuals divided by age group performed isometric muscle contractions at maximum effort for various movements of hip joint flexion and extension and knee joint flexion and extension, and the accompanying resisting force was measured and maximum muscle strength value (moment max, Mm) was calculated. Body weight and limb segment length (thigh and lower leg length) were measured, and Mf was calculated using anthropometric measures and theoretical calculation. There was a linear correlation between Mf and Mm in each of the four movement types in all groups, excepting knee flexion in elderly. However, the formula for predicting maximum muscle strength was not sufficiently compatible in middle-aged and elderly adults, suggesting that the formula obtained in this study is applicable in young adults only. PMID:28133549
Usa, Hideyuki; Matsumura, Masashi; Ichikawa, Kazuna; Takei, Hitoshi
2017-01-01
This study attempted to develop a formula for predicting maximum muscle strength value for young, middle-aged, and elderly adults using theoretical Grade 3 muscle strength value (moment fair: Mf )-the static muscular moment to support a limb segment against gravity-from the manual muscle test by Daniels et al. A total of 130 healthy Japanese individuals divided by age group performed isometric muscle contractions at maximum effort for various movements of hip joint flexion and extension and knee joint flexion and extension, and the accompanying resisting force was measured and maximum muscle strength value (moment max, Mm ) was calculated. Body weight and limb segment length (thigh and lower leg length) were measured, and Mf was calculated using anthropometric measures and theoretical calculation. There was a linear correlation between Mf and Mm in each of the four movement types in all groups, excepting knee flexion in elderly. However, the formula for predicting maximum muscle strength was not sufficiently compatible in middle-aged and elderly adults, suggesting that the formula obtained in this study is applicable in young adults only.
Directory of Open Access Journals (Sweden)
Hideyuki Usa
2017-01-01
Full Text Available This study attempted to develop a formula for predicting maximum muscle strength value for young, middle-aged, and elderly adults using theoretical Grade 3 muscle strength value (moment fair: Mf—the static muscular moment to support a limb segment against gravity—from the manual muscle test by Daniels et al. A total of 130 healthy Japanese individuals divided by age group performed isometric muscle contractions at maximum effort for various movements of hip joint flexion and extension and knee joint flexion and extension, and the accompanying resisting force was measured and maximum muscle strength value (moment max, Mm was calculated. Body weight and limb segment length (thigh and lower leg length were measured, and Mf was calculated using anthropometric measures and theoretical calculation. There was a linear correlation between Mf and Mm in each of the four movement types in all groups, excepting knee flexion in elderly. However, the formula for predicting maximum muscle strength was not sufficiently compatible in middle-aged and elderly adults, suggesting that the formula obtained in this study is applicable in young adults only.
Directory of Open Access Journals (Sweden)
Daichi Sone
Full Text Available Psychosis is one of the most important psychiatric comorbidities in temporal lobe epilepsy (TLE, and its pathophysiology still remains unsolved. We aimed to explore the connectivity differences of structural neuroimaging between TLE with and without psychosis using a graph theoretical analysis, which is an emerging mathematical method to investigate network connections in the brain as a small-world system.We recruited 11 TLE patients with unilateral hippocampal sclerosis (HS presenting psychosis or having a history of psychosis (TLE-P group. As controls, 15 TLE patients with unilateral HS without any history of psychotic episodes were also recruited (TLE-N group. For graph theoretical analysis, the normalized gray matter images of both groups were subjected to Graph Analysis Toolbox (GAT. As secondary analyses, each group was compared to 14 age- and gender-matched healthy subjects.The hub node locations were found predominantly in the ipsilateral hemisphere in the TLE-N group, and mainly on the contralateral side in the TLE-P group. The TLE-P group showed significantly higher characteristic path length, transitivity, lower global efficiency, and resilience to random or targeted attack than those of the TLE-N group. The regional comparison in betweenness centrality revealed significantly decreased connectivity in the contralateral temporal lobe, ipsilateral middle frontal gyrus, and bilateral postcentral gyri in the TLE-P group. The healthy subjects showed well-balanced nodes/edges distributions, similar metrics to TLE-N group except for higher small-worldness/modularity/assortativity, and various differences of regional betweenness/clustering.In TLE with psychosis, graph theoretical analysis of structural imaging revealed disrupted connectivity in the contralateral hemisphere. The network metrics suggested that the existence of psychosis can bring vulnerability and decreased efficiency of the whole-brain network. The sharp differences in
Goldberg, David H; Victor, Jonathan D; Gardner, Esther P; Gardner, Daniel
2009-09-01
Conventional methods widely available for the analysis of spike trains and related neural data include various time- and frequency-domain analyses, such as peri-event and interspike interval histograms, spectral measures, and probability distributions. Information theoretic methods are increasingly recognized as significant tools for the analysis of spike train data. However, developing robust implementations of these methods can be time-consuming, and determining applicability to neural recordings can require expertise. In order to facilitate more widespread adoption of these informative methods by the neuroscience community, we have developed the Spike Train Analysis Toolkit. STAToolkit is a software package which implements, documents, and guides application of several information-theoretic spike train analysis techniques, thus minimizing the effort needed to adopt and use them. This implementation behaves like a typical Matlab toolbox, but the underlying computations are coded in C for portability, optimized for efficiency, and interfaced with Matlab via the MEX framework. STAToolkit runs on any of three major platforms: Windows, Mac OS, and Linux. The toolkit reads input from files with an easy-to-generate text-based, platform-independent format. STAToolkit, including full documentation and test cases, is freely available open source via http://neuroanalysis.org , maintained as a resource for the computational neuroscience and neuroinformatics communities. Use cases drawn from somatosensory and gustatory neurophysiology, and community use of STAToolkit, demonstrate its utility and scope.
Comparative analysis of superintegrons: engineering extensive genetic diversity in the Vibrionaceae.
Rowe-Magnus, Dean A; Guerout, Anne-Marie; Biskri, Latefa; Bouige, Philippe; Mazel, Didier
2003-03-01
Integrons are natural tools for bacterial evolution and innovation. Their involvement in the capture and dissemination of antibiotic-resistance genes among Gram-negative bacteria is well documented. Recently, massive ancestral versions, the superintegrons (SIs), were discovered in the genomes of diverse proteobacterial species. SI gene cassettes with an identifiable activity encode proteins related to simple adaptive functions, including resistance, virulence, and metabolic activities, and their recruitment was interpreted as providing the host with an adaptive advantage. Here, we present extensive comparative analysis of SIs identified among the Vibrionaceae. Each was at least 100 kb in size, reaffirming the participation of SIs in the genome plasticity and heterogeneity of these species. Phylogenetic and localization data supported the sedentary nature of the functional integron platform and its coevolution with the host genome. Conversely, comparative analysis of the SI cassettes was indicative of both a wide range of origin for the entrapped genes and of an active cassette assembly process in these bacterial species. The signature attC sites of each species displayed conserved structural characteristics indicating that symmetry rather than sequence was important in the recognition of such a varied collection of target recombination sequences by a single site-specific recombinase. Our discovery of various addiction module cassettes within each of the different SIs indicates a possible role for them in the overall stability of large integron cassette arrays.
Energy Technology Data Exchange (ETDEWEB)
Soares, Breno Almeida; Firme, Caio Lima, E-mail: firme.caio@gmail.com, E-mail: caiofirme@quimica.ufrn.br [Universidade Federal do Rio Grande do Norte (UFRN), Natal, RN (Brazil). Instituto de Quimica; Maciel, Maria Aparecida Medeiros [Universidade Potiguar, Natal, RN (Brazil). Programa de Pos-graduacao em Biotecnologia; Kaiser, Carlos R. [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Instituto de Quimica; Schilling, Eduardo; Bortoluzzi, Adailton J. [Universidade Federal de Santa Catarina (UFSC), Florianopolis, SC (Brazil). Departamento de Quimica
2014-04-15
trans-Dehydrocrotonin (t-DCTN) a bioactive 19-nor-diterpenoid clerodane type isolated from Croton cajucara Benth, is one of the most investigated clerodane in the current literature. In this work, a new approach joining X-ray diffraction data, nuclear magnetic resonance (NMR) data and theoretical calculations was applied to the thorough characterization of t-DCTN. For that, the geometry of t-DCTN was reevaluated by X-ray diffraction as well as {sup 1}H and {sup 13}C NMR data, whose geometrical parameters where compared to those obtained from B3LYP/6-311G++(d,p) level of theory. From the evaluation of both calculated and experimental values of {sup 1}H and {sup 13}C NMR chemical shifts and spin-spin coupling constants, it was found very good correlations between theoretical and experimental magnetic properties of t-DCTN. Additionally, the delocalization indexes between hydrogen atoms correlated accurately with theoretical and experimental spin-spin coupling constants. An additional topological analysis from quantum theory of atoms in molecules (QTAIM) showed intramolecular interactions for t-DCTN. (author)
Dream-reality confusion in Borderline Personality Disorder: A theoretical analysis
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Dagna eSkrzypińska
2015-09-01
Full Text Available This paper presents an analysis of dream-reality confusion (DRC in relation to the characteristics of borderline personality disorder (BPD, based on research findings and theoretical considerations. It is hypothesized that people with BPD are more likely to experience DRC compared to people in non-clinical population. Several variables related to this hypothesis were identified through a theoretical analysis of the scientific literature. Sleep disturbances: Problems with sleep are found in 15-95.5% of people with BPD (Hafizi, 2013, and unstable sleep and wake cycles, which occur in BPD (Fleischer et al., 2012, are linked to DRC. Dissociation: Nearly two-thirds of people with BPD experience dissociative symptoms (Korzekwa and Pain, 2009 and dissociative symptoms are correlated with a fantasy proneness; both dissociative symptoms and fantasy proneness are related to DRC (Giesbrecht and Merckelbach, 2006. Negative dream content: People with BPD have nightmares more often than other people (Semiz et al., 2008; dreams that are more likely to be confused with reality tend to be more realistic and unpleasant, and are reflected in waking behavior (Rassin et al., 2001. Cognitive disturbances: Many BPD patients experience various cognitive disturbances, including problems with reality testing (Fiqueierdo, 2006; Mosquera et al., 2011, which can foster DRC. Thin boundaries: People with thin boundaries are more prone to DRC than people with thick boundaries, and people with BPD tend to have thin boundaries (Hartmann, 2011. The theoretical analysis on the basis of these findings suggests that people who suffer from BPD may be more susceptible to confusing dream content with actual waking events.
Cepstral Peak Sensitivity: A Theoretic Analysis and Comparison of Several Implementations.
Skowronski, Mark D; Shrivastav, Rahul; Hunter, Eric J
2015-11-01
The aim of this study was to develop a theoretic analysis of the cepstral peak (CP), to compare several CP software programs, and to propose methods for reducing variability in CP estimation. Descriptive, experimental study. The theoretic CP value of a pulse train was derived and compared with estimates computed for pulse train WAV files using available CP software programs: (1) Hillenbrand's CP prominence (CPP) software (Western Michigan University, Kalamazoo, MI), (2) KayPENTAX (Montvale, NJ) Multi-Speech implementation of CPP, and (3) a MATLAB (The Mathworks, Natick, MA, version R2014a) implementation using cepstral interpolation. The CP variation was also investigated for synthetic breathy vowels. For pulse trains with period T samples, the theoretic CP is 1/2+ε/T, |ε|<0.1 for all pulse trains (ε=0 for integer T). For fundamental frequencies between 70 and 230Hz, the CP mean±standard deviation was 0.496±0.002 using cepstral interpolation and 0.29±0.03 using Hillenbrand's software, whereas CPP was 35.0±3.8dB using Hillenbrand's software and 20.5±2.7dB using KayPENTAX's software. The CP and CPP versus signal-to-noise ratio for synthetic breathy vowels were fit to a logistic model for the Hillenbrand (R(2)=0.92) and KayPENTAX (R(2)=0.82) estimators as well as an ideal estimator (R(2)=0.98), which used a period-synchronous analysis. The findings indicate that several variables unrelated to the signal itself impact CP values, with some factors introducing large variability in CP values that would otherwise be attributed to the signal (eg, voice quality). Variability may be reduced by using a period-synchronous analysis with Hann windows. Copyright © 2015 The Voice Foundation. Published by Elsevier Inc. All rights reserved.
Liu, Xuejuan; Tian, Falin; Yue, Tongtao; Zhang, Xianren; Zhong, Chongli
2016-11-09
The shape deformation of membrane nanotubes is studied by a combination of theoretical analysis and molecular simulation. First we perform free energy analysis to demonstrate the effects of various factors on two ideal states for the pearling transition, and then we carry out dissipative particle dynamics simulations, through which various types of membrane tube deformation are found, including membrane pearling, buckling, and bulging. Different models for inducing tube deformation, including the osmotic pressure, area difference and spontaneous curvature models, are considered to investigate tubular instabilities. Combined with free energy analysis, our simulations show that the origin of the deformation of membrane tubes in different models can be classified into two categories: effective spontaneous curvature and membrane tension. We further demonstrate that for different models, a positive membrane tension is required for the pearling transition. Finally we show that different models can be coupled to effectively deform the membrane tube.
Michalska, Katarzyna; Mizera, Mikołaj; Lewandowska, Kornelia; Cielecka-Piontek, Judyta
2016-07-01
Tedizolid is the newest antibacterial agent from the oxazolidinone class. For its identification, FT-IR (2000-400 cm-1) and Raman (2000-400 cm-1) analyses were proposed. Studies of the enantiomeric purity of tedizolid were conducted based on ultraviolet-circular dichroism (UV-CD) analysis. Density functional theory (DFT) with the B3LYP hybrid functional and 6-311G(2df,2pd) basis set was used for support of the analysis of the FT-IR and Raman spectra. Theoretical methods made it possible to conduct HOMO and LUMO analysis, which was used to determine the charge transfer for two tedizolid enantiomers. Molecular electrostatic potential maps were calculated with the DFT method for both tedizolid enantiomers. The relationship between the results of ab initio calculations and knowledge about the chemical-biological properties of R- and S-tedizolid enantiomers is also discussed.
A Theoretical Analysis of Authentication, Privacy and Reusability Across Secure Biometric Systems
Wang, Ye; Draper, Stark C; Ishwar, Prakash
2011-01-01
We present a theoretical framework for the analysis of privacy and security tradeoffs in secure biometric authentication systems. We use this framework to conduct a comparative information-theoretic analysis of two biometric systems that are based on linear error correction codes, namely fuzzy commitment and secure sketches. We derive upper bounds for the probability of false rejection ($P_{FR}$) and false acceptance ($P_{FA}$) for these systems. We use mutual information to quantify the information leaked about a user's biometric identity, in the scenario where one or multiple biometric enrollments of the user are fully or partially compromised. We also quantify the probability of successful attack ($P_{SA}$) based on the compromised information. Our analysis reveals that fuzzy commitment and secure sketch systems have identical $P_{FR}, P_{FA}, P_{SA}$ and information leakage, but secure sketch systems have lower storage requirements. We analyze both single-factor (keyless) and two-factor (key-based) varian...
Sholtes, Joel; Werbylo, Kevin; Bledsoe, Brian
2014-10-01
Theoretical approaches to magnitude-frequency analysis (MFA) of sediment transport in channels couple continuous flow probability density functions (PDFs) with power law flow-sediment transport relations (rating curves) to produce closed-form equations relating MFA metrics such as the effective discharge, Qeff, and fraction of sediment transported by discharges greater than Qeff, f+, to statistical moments of the flow PDF and rating curve parameters. These approaches have proven useful in understanding the theoretical drivers behind the magnitude and frequency of sediment transport. However, some of their basic assumptions and findings may not apply to natural rivers and streams with more complex flow-sediment transport relationships or management and design scenarios, which have finite time horizons. We use simple numerical experiments to test the validity of theoretical MFA approaches in predicting the magnitude and frequency of sediment transport. Median values of Qeff and f+ generated from repeated, synthetic, finite flow series diverge from those produced with theoretical approaches using the same underlying flow PDF. The closed-form relation for f+ is a monotonically increasing function of flow variance. However, using finite flow series, we find that f+ increases with flow variance to a threshold that increases with flow record length. By introducing a sediment entrainment threshold, we present a physical mechanism for the observed diverging relationship between Qeff and flow variance in fine and coarse-bed channels. Our work shows that through complex and threshold-driven relationships sediment transport mode, channel morphology, flow variance, and flow record length all interact to influence estimates of what flow frequencies are most responsible for transporting sediment in alluvial channels.
Theoretical Analysis of the Pressure Oscillation Phenomena in Capillary Pumped Loop
Institute of Scientific and Technical Information of China (English)
ZhangJiaxun; HouZengqi; 等
1998-01-01
Based on the physical model of caplillary pumped loop(CPL)system,the phenomena of pressure oscillation are simplified and analyzed.From a set of non-linear differential equations,the influence of ststem parameters on the performance of the CPL is discussed,including the working temperature (the set point),loop resistance,vapor volume etc.From the analysis,some measures were taken to improve the performance of the loop,Meanwhile ,the reason why the deprive of the CPL occurs during the operation is given by analyzing the theoretical calculation results.
Lobach, I.; Benediktovitch, A.
2016-07-01
The possibility of quantitative texture analysis by means of parametric x-ray radiation (PXR) from relativistic electrons with Lorentz factor γ > 50MeV in a polycrystal is considered theoretically. In the case of rather smooth orientation distribution function (ODF) and large detector (θD >> 1/γ) the universal relation between ODF and intensity distribution is presented. It is shown that if ODF is independent on one from Euler angles, then the texture is fully determined by angular intensity distribution. Application of the method to the simulated data shows the stability of the proposed algorithm.
THEORETICAL ANALYSIS OF USING AIRFLOW TO PURGE RESIDUAL WATER IN AN INCLINED PIPE
Institute of Scientific and Technical Information of China (English)
SHEN Fang(沈芳); YAN Zong-yi(严宗毅); ZHAO Yao-hua(赵耀华); Kiyoshi Horii
2002-01-01
A refined theoretical analysis for using the spiral airflow and axial airflow to purge residual water in an inclined pipe was presented. The computations reveal that, in most cases, the spiral flow can purge the residual water in the inclined pipe indeed while the axial flow may induce back flow of the water, just as predicted in the experiments presented by Horii and Zhao et al. In addition, the effects of various initial conditions on water purging were studied in detail for both the spiral and axial flow cases.
multiplierz: an extensible API based desktop environment for proteomics data analysis
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Webber James T
2009-10-01
Full Text Available Abstract Background Efficient analysis of results from mass spectrometry-based proteomics experiments requires access to disparate data types, including native mass spectrometry files, output from algorithms that assign peptide sequence to MS/MS spectra, and annotation for proteins and pathways from various database sources. Moreover, proteomics technologies and experimental methods are not yet standardized; hence a high degree of flexibility is necessary for efficient support of high- and low-throughput data analytic tasks. Development of a desktop environment that is sufficiently robust for deployment in data analytic pipelines, and simultaneously supports customization for programmers and non-programmers alike, has proven to be a significant challenge. Results We describe multiplierz, a flexible and open-source desktop environment for comprehensive proteomics data analysis. We use this framework to expose a prototype version of our recently proposed common API (mzAPI designed for direct access to proprietary mass spectrometry files. In addition to routine data analytic tasks, multiplierz supports generation of information rich, portable spreadsheet-based reports. Moreover, multiplierz is designed around a "zero infrastructure" philosophy, meaning that it can be deployed by end users with little or no system administration support. Finally, access to multiplierz functionality is provided via high-level Python scripts, resulting in a fully extensible data analytic environment for rapid development of custom algorithms and deployment of high-throughput data pipelines. Conclusion Collectively, mzAPI and multiplierz facilitate a wide range of data analysis tasks, spanning technology development to biological annotation, for mass spectrometry-based proteomics research.
Alston, Antoine J.; Hilton, Lashawn; English, Chastity Warren; Elbert, Chanda; Wakefield, Dexter
2011-01-01
The study reported here sought to determine the perception of North Carolina County Cooperative Extension directors in regard to the North Carolina Cooperative Extension Service's role in bridging the digital divide. It was perceived by respondents that variables such as income, education, gender, disability status, race/ethnicity, age, and…
Virtual Focus Groups in Extension: A Useful Approach to Audience Analysis
Warner, Laura A.
2014-01-01
As change agents, Extension educators may begin their program planning by identifying the audience's perceived barriers and benefits to adopting some behavior that will benefit the community. Extension professionals and researchers have used in-person focus groups to understand an audience, and they can also administer them as…
New Power Quality Analysis Method Based on Chaos Synchronization and Extension Neural Network
Directory of Open Access Journals (Sweden)
Meng-Hui Wang
2014-10-01
Full Text Available A hybrid method comprising a chaos synchronization (CS-based detection scheme and an Extension Neural Network (ENN classification algorithm is proposed for power quality monitoring and analysis. The new method can detect minor changes in signals of the power systems. Likewise, prominent characteristics of system signal disturbance can be extracted by this technique. In the proposed approach, the CS-based detection method is used to extract three fundamental characteristics of the power system signal and an ENN-based clustering scheme is then applied to detect the state of the signal, i.e., normal, voltage sag, voltage swell, interruption or harmonics. The validity of the proposed method is demonstrated by means of simulations given the use of three different chaotic systems, namely Lorenz, New Lorenz and Sprott. The simulation results show that the proposed method achieves a high detection accuracy irrespective of the chaotic system used or the presence of noise. The proposed method not only achieves higher detection accuracy than existing methods, but also has low computational cost, an improved robustness toward noise, and improved scalability. As a result, it provides an ideal solution for the future development of hand-held power quality analyzers and real-time detection devices.
Non-extensive statistical analysis of meteor showers and lunar flashes
Betzler, A. S.; Borges, E. P.
2015-02-01
The distribution of meteor magnitudes is usually supposed to be described by power laws. However, this relationship is not able to model the whole data set, and the parameters are considered to be dependent on the magnitude intervals. We adopt a statistical distribution derived from Tsallis non-extensive statistical mechanics which is able to model the whole magnitude range. We combined meteor data from various sources, ranging from telescopic meteors to lunar impactors. Our analysis shows that the probability distribution of magnitudes of International Meteor Organization (IMO) and Meteor Observation and Recovery Project data are similar. The distribution of IMO visual magnitudes indicates that 2.4 ± 0.5 per cent of the meteors of a shower may be telescopic (m > 6). We note that the distribution of duration of lunar flashes follows a power law, and a comparison with the distribution of meteor showers suggests the occurrence of observational bias. The IMO sporadic meteor distribution also seems to be influenced by observational factors.
Static progressive versus three-point elbow extension splinting: a mathematical analysis.
Chinchalkar, Shrikant J; Pearce, Joshua; Athwal, George S
2009-01-01
Elbow joint contractures are often treated by using static progressive, dynamic, turnbuckle, or serial static splinting. These splint designs are effective in regaining functional elbow range of motion due to the high forces applied to the contracted tissues; however, regaining terminal elbow extension remains a challenge. Static progressive splints are commonly used to initiate treatment, however, are considered less effective in regaining terminal extension. Recently, the concept of converting a static progressive splint into a three-point static progressive splint (TPSPS) to regain terminal extension has been introduced. This paper mathematically analyzes the compressive and rotational forces in static progressive and TPSPSs. Our hypothesis was that three-point static progressive splinting was superior to the standard static progressive elbow extension splint in applying rotational forces to the elbow at terminal extension.
Mathammal, R.; Sudha, N.; Shankar, R.; Rajaboopathi, M.; Janagi, S.; Prabavathi, B.
2017-03-01
This report discusses crystal structure, molecular arrangements, vibrational analysis, UV-Vis-NIR spectrum, fluorescence emission and second harmonic generation (SHG) efficiency of piperazinium L-tartrate (PPZ2+·Tart2-) crystals with the support of theoretical analysis. A good optical quality PPZ2+·Tart2- crystals were grown from slow evaporation of aqueous solution. The PPZ2+·Tart2- crystal belongs to monoclinic system with non-centrosymmetric space group P21. The charge transfer from donor to acceptor moieties and corresponding changes in the bond lengths and bond angles have been observed. The observed functional group vibrations in the experimental FTIR and the Raman spectrum were assigned and compared with theoretical wavenumbers of PPZ2+·Tart2-.The electron distribution on the donor and acceptor in PPZ2+·Tart2- has been clearly visualised using molecular electrostatic potential map. Compared with L-tartaric acid, red shift was observed in absorption and fluorescence spectrum. The low value of dielectric constant and dielectric loss at the higher frequency and its high second harmonic efficiency suggest PPZ2+·Tart2- crystal is less defect free and suitable for NLO applications.
Group theoretical analysis of the H3+ +H2 ↔ H5+ reaction
Lin, Zhou
2016-06-01
The H3+ +H2 →H2 + H3+ proton transfer reaction is complicated due to the proton scrambling from the large amplitude motions in the H5+ intermediate. In order to understand this reaction, high-resolution spectroscopic studies are necessary for the reactants/products and the intermediate, and the group theoretical analysis is an essential aspect in the prediction and interpretation of these spectra. With five indistinguishable protons, H5+ is characterized using the G240 complete nuclear permutation-inversion (CNPI) group. For most of the configurations sampled by the reaction path, the feasible permutations depend on the distance between the H3+ and H2 fragments. Subgroups of G240 can be used to describe these feasible permutations. Specifically, we consider two limits of the molecular configurations. The equilibrium structure of H5+ , i.e., [H2 -H -H2 ]+, can be described using the G16 molecular symmetry group, while the dissociation products, i.e., H3+ ⋯H2 , require the G24 molecular symmetry group. In the present study, a group theoretical analysis is performed for both limits, providing the symmetries for the nuclear spins and rovibrational wave functions. Also, spectroscopic properties for [H2 -H -H2 ]+, particularly rovibrational couplings and electric dipole selection rules, as well as correlations of energy levels between [H2 -H -H2 ]+ and H3+ ⋯H2 , are obtained.
Casiano, M. J.
2011-01-01
The Common Extensive Cryogenic Engine program demonstrated the operation of a deep throttling engine design. The program, spanning five years from August 2005 to July 2010, funded testing through four separate engine demonstration test series. Along with successful completion of multiple objectives, a discrete response of approximately 4000 Hz was discovered and explored throughout the program. The typical low-amplitude acoustic response was evident in the chamber measurement through almost every operating condition; however, at certain off-nominal operating conditions, the response became discrete with higher amplitude. This paper summarizes the data reduction, characterization, and analysis of the 4,000 Hz response for the entire program duration, using the large amount of data collected. Upon first encountering the response, new objectives and instrumentation were incorporated in future test series to specifically collect 4,000 Hz data. The 4,000 Hz response was identified as being related to the first tangential acoustic mode by means of frequency estimation and spatial decomposition. The latter approach showed that the effective node line of the mode was aligned with the manifold propellant inlets with standing waves and quasi-standing waves present at various times. Contour maps that contain instantaneous frequency and amplitude trackings of the response were generated as a significant improvement to historical manual approaches of data reduction presentation. Signal analysis and dynamic data reduction also uncovered several other features of the response including a stable limit cycle, the progressive engagement of subsequent harmonics, the U-shaped time history, an intermittent response near the test-based neutral stability region, other acoustic modes, and indications of modulation with a separate subsynchronous response. Although no engine damage related to the acoustic mode was noted, the peak-to-peak fluctuating pressure amplitude achieved 12.1% of the
Life-cycle cost-benefit analysis of extensive vegetated roof systems.
Carter, Timothy; Keeler, Andrew
2008-05-01
The built environment has been a significant cause of environmental degradation in the previously undeveloped landscape. As public and private interest in restoring the environmental integrity of urban areas continues to increase, new construction practices are being developed that explicitly value beneficial environmental characteristics. The use of vegetation on a rooftop--commonly called a green roof--as an alternative to traditional roofing materials is an increasingly utilized example of such practices. The vegetation and growing media perform a number of functions that improve environmental performance, including: absorption of rainfall, reduction of roof temperatures, improvement in ambient air quality, and provision of urban habitat. A better accounting of the green roof's total costs and benefits to society and to the private sector will aid in the design of policy instruments and educational materials that affect individual decisions about green roof construction. This study uses data collected from an experimental green roof plot to develop a benefit cost analysis (BCA) for the life cycle of extensive (thin layer) green roof systems in an urban watershed. The results from this analysis are compared with a traditional roofing scenario. The net present value (NPV) of this type of green roof currently ranges from 10% to 14% more expensive than its conventional counterpart. A reduction of 20% in green roof construction cost would make the social NPV of the practice less than traditional roof NPV. Considering the positive social benefits and relatively novel nature of the practice, incentives encouraging the use of this practice in highly urbanized watersheds are strongly recommended.
Hsu, Anne S; Vitanyi, Paul M B
2010-01-01
There is much debate over the degree to which language learning is governed by innate language-specific biases, or acquired through cognition-general principles. Here we examine the probabilistic language acquisition hypothesis on three levels: We outline a novel theoretical result showing that it is possible to learn the exact generative model underlying a wide class of languages, purely from observing samples of the language. We then describe a recently proposed practical framework, which quantifies natural language learnability, allowing specific learnability predictions to be made for the first time. In previous work, this framework was used to make learnability predictions for a wide variety of linguistic constructions, for which learnability has been much debated. Here, we present a new experiment which tests these learnability predictions. We find that our experimental results support the possibility that these linguistic constructions are acquired probabilistically from cognition-general principles.
Experimental and theoretical oscillator strengths of Mg I for accurate abundance analysis
Rhodin, A Pehlivan; Nilsson, H; Jonsson, P
2016-01-01
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 alpha-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-r...
Berezovska, Ganna; Mostarda, Stefano; Rao, Francesco
2012-01-01
Molecular simulations as well as single molecule experiments have been widely analyzed in terms order parameters, the latter representing candidate probes for the relevant degrees of freedom. Notwithstanding this approach is very intuitive, mounting evidence showed that such description is not accurate, leading to ambiguous definitions of states and wrong kinetics. To overcome these limitations a framework making use of order parameter fluctuations in conjunction with complex network analysis is investigated. Derived from recent advances in the analysis of single molecule time traces, this approach takes into account of the fluctuations around each time point to distinguish between states that have similar values of the order parameter but different dynamics. Snapshots with similar fluctuations are used as nodes of a transition network, the clusterization of which into states provides accurate Markov-State-Models of the system under study. Application of the methodology to theoretical models with a noisy orde...
Energy Technology Data Exchange (ETDEWEB)
Roudeau, P.; Stocchi, A. [Laboratoire de l' Accelerateur Lineaire, 91 - Orsay (France); Ciuchini, M.; Lubicz, V. [Rome Univ., INFN (Italy); D' Agostini, G.; Franco, E.; Martinelli, G. [Rome Univ. La Sapienza and Sezione INFN, (Italy); Parodi, F. [Universita di Genova and INFN, Dipt. di Fisica (Italy)
2000-12-01
Within the Standard Model, a review of the current determination of the sides and angles of the CKM unitarity triangle is presented, using experimental constraints from the measurements of |{epsilon}{sub K}|, |V{sub ub}/V{sub cb}|, {delta}m{sub d} and from the limit on {delta}m{sub s}, available in September 2000. Results from the experimental search for B{sup 0}{sub s}-B-bar{sup 0}{sub s} oscillations are introduced in the present analysis using the likelihood. Special attention is devoted to the determination of the theoretical uncertainties. The purpose of the analysis is to infer regions where the parameters of interest lie with given probabilities. The BaBar '95% C.L. scanning' method is also commented. (authors)
Chen, Hai-Long; Jin, Feng-Nian; Fan, Hua-Lin
2013-02-01
Due to the wide applications of arches in underground protective structures, dynamic analysis of circular arches including soil-structure interactions is important. In this paper, an exact solution of the forced vibration of circular arches subjected to subsurface denotation forces is obtained. The dynamic soil-structure interaction is considered with the introduction of an interfacial damping between the structure element and the surrounding soil into the equation of motion. By neglecting the influences of shear, rotary inertia and tangential forces and assuming the arch incompressible, the equations of motion of the buried arches were set up. Analytical solutions of the dynamic responses of the protective arches were deduced by means of modal superposition. Arches with different opening angles, acoustic impedances and rise-span ratios were analyzed to discuss their influences on an arch. The theoretical analysis suggests blast loads for elastic designs and predicts the potential failure modes for buried protective arches.
NDARC-NASA Design and Analysis of Rotorcraft Theoretical Basis and Architecture
Johnson, Wayne
2010-01-01
The theoretical basis and architecture of the conceptual design tool NDARC (NASA Design and Analysis of Rotorcraft) are described. The principal tasks of NDARC are to design (or size) a rotorcraft to satisfy specified design conditions and missions, and then analyze the performance of the aircraft for a set of off-design missions and point operating conditions. The aircraft consists of a set of components, including fuselage, rotors, wings, tails, and propulsion. For each component, attributes such as performance, drag, and weight can be calculated. The aircraft attributes are obtained from the sum of the component attributes. NDARC provides a capability to model general rotorcraft configurations, and estimate the performance and attributes of advanced rotor concepts. The software has been implemented with low-fidelity models, typical of the conceptual design environment. Incorporation of higher-fidelity models will be possible, as the architecture of the code accommodates configuration flexibility, a hierarchy of models, and ultimately multidisciplinary design, analysis and optimization.
Guoji, Shen; McLaughlin, Stephen; Yongcheng, Xu; White, Paul
2014-02-01
Condition monitoring and fault diagnosis is an important issue for gearbox maintenance and safety. The critical process involved in such activities is to extract reliable features representative of the condition of the gears or gearbox. In this paper a framework is presented for the application of bispectrum to the analysis of gearbox vibration. The bispectrum of a composite signal consisting of multiple periodic components has peaks at the bifrequencies that correspond to closely related components which can be produced by any nonlinearity. As a result, biphase verification is necessary to decrease false-alarming for any bispectrum-based method. A model based on modulated signals is adopted to reveal the bispectrum characteristics for the vibration of a faulty gear, and the corresponding amplitude and phase of the bispectrum expression are deduced. Therefore, a diagnostic approach based on the theoretical result is derived and verified by the analysis of a set of vibration signals from a helicopter gearbox.
Zhuang, Jun
2015-01-01
Maximizing reader insights into the roles of intelligent agents in networks, air traffic and emergency departments, this volume focuses on congestion in systems where safety and security are at stake, devoting special attention to applying game theoretic analysis of congestion to: protocols in wired and wireless networks; power generation, air transportation and emergency department overcrowding. Reviewing exhaustively the key recent research into the interactions between game theory, excessive crowding, and safety and security elements, this book establishes a new research angle by illustrating linkages between the different research approaches and serves to lay the foundations for subsequent analysis. Congestion (excessive crowding) is defined in this work as all kinds of flows; e.g., road/sea/air traffic, people, data, information, water, electricity, and organisms. Analyzing systems where congestion occurs – which may be in parallel, series, interlinked, or interdependent, with flows one way or both way...
Open source tools for the information theoretic analysis of neural data.
Ince, Robin A A; Mazzoni, Alberto; Petersen, Rasmus S; Panzeri, Stefano
2010-01-01
The recent and rapid development of open source software tools for the analysis of neurophysiological datasets consisting of simultaneous multiple recordings of spikes, field potentials and other neural signals holds the promise for a significant advance in the standardization, transparency, quality, reproducibility and variety of techniques used to analyze neurophysiological data and for the integration of information obtained at different spatial and temporal scales. In this review we focus on recent advances in open source toolboxes for the information theoretic analysis of neural responses. We also present examples of their use to investigate the role of spike timing precision, correlations across neurons, and field potential fluctuations in the encoding of sensory information. These information toolboxes, available both in MATLAB and Python programming environments, hold the potential to enlarge the domain of application of information theory to neuroscience and to lead to new discoveries about how neurons encode and transmit information.
Directory of Open Access Journals (Sweden)
Davidović Nebojša
2010-01-01
Full Text Available The paper presents a brief description of experiment within the research project 'Theoretical and experimental analysis of interaction of shallow reinforced concrete foundations and soil for the purpose of improvement of national regulations and implementaation of Eurocode system' where in situ tests of a series of reinforced concrete foundation footing were performed, by loading until failure. As a rule, methods for calculation of shallow foundations settlement on granular soils overestimate the expected settlement, and underestimate soil bearing capacity, which results in a conservative foundation design. In order to test accuracy and reliability of the different settlements prediction methods, a comparative analysis of settlements calculated using these methods and those measured during experiment, was performed.
Graph theoretical analysis and application of fMRI-based brain network in Alzheimer's disease
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LIU Xue-na
2012-08-01
Full Text Available Alzheimer's disease (AD, a progressive neurodegenerative disease, is clinically characterized by impaired memory and many other cognitive functions. However, the pathophysiological mechanisms underlying the disease are not thoroughly understood. In recent years, using functional magnetic resonance imaging (fMRI as well as advanced graph theory based network analysis approach, several studies of patients with AD suggested abnormal topological organization in both global and regional properties of functional brain networks, specifically, as demonstrated by a loss of small-world network characteristics. These studies provide novel insights into the pathophysiological mechanisms of AD and could be helpful in developing imaging biomarkers for disease diagnosis. In this paper we introduce the essential concepts of complex brain networks theory, and review recent advances of the study on human functional brain networks in AD, especially focusing on the graph theoretical analysis of small-world network based on fMRI. We also propound the existent problems and research orientation.
A thematic analysis of theoretical models for translational science in nursing: mapping the field.
Mitchell, Sandra A; Fisher, Cheryl A; Hastings, Clare E; Silverman, Leanne B; Wallen, Gwenyth R
2010-01-01
The quantity and diversity of conceptual models in translational science may complicate rather than advance the use of theory. This paper offers a comparative thematic analysis of the models available to inform knowledge development, transfer, and utilization. Literature searches identified 47 models for knowledge translation. Four thematic areas emerged: (1) evidence-based practice and knowledge transformation processes, (2) strategic change to promote adoption of new knowledge, (3) knowledge exchange and synthesis for application and inquiry, and (4) designing and interpreting dissemination research. This analysis distinguishes the contributions made by leaders and researchers at each phase in the process of discovery, development, and service delivery. It also informs the selection of models to guide activities in knowledge translation. A flexible theoretical stance is essential to simultaneously develop new knowledge and accelerate the translation of that knowledge into practice behaviors and programs of care that support optimal patient outcomes.
A Theoretical Analysis of the Mission Statement Based on the Axiological Approach
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Marius-Costel EŞI
2016-12-01
Full Text Available The aim of this work is focused on a theoretical analysis of formulating the mission statement of business organizations in relation to the idea of the organizational axiological core. On one hand, we consider the CSR-Corporate Social Responsibility which, in our view, must be brought into direct connection both with the moral entrepreneurship (which should support the philosophical perspective of the statement of business organizations mission and the purely economic entrepreneurship based on profit maximization (which should support the pragmatic perspective. On the other hand, an analysis of the moral concepts which should underpin business is becoming fundamental, in our view, as far as the idea of the social specific value of the social entrepreneurship is evidenced. Therefore, our approach highlights a number of epistemic explanations in relation to the actual practice dimension.
DEFF Research Database (Denmark)
Fetene, Gebeyehu Manie
electric cars. The last chapter deals with analysis of energy consumption rate and its determinants of electric cars under the hands of customers. A variety of techniques are used including analysis of field data, economics laboratory experiments and theoretical modeling with simulation. Chapter one...... and Pricing of Electric Vehicle Recharging’, proposes, and tests at laboratory, contracts about recharging BEVs combining the ultimatum game framework and the myopic loss aversion (MLA) behavioral hypothesis. The model represents the behavior of EV-owners trading-off between the amount of the discount on fee...... price as long-term contracts may curtail MLA behavior and help BEV owners to choose cost minimizing recharging time and, simultaneously, may help to reduce BEVs impact on the electricity grid system. The fourth chapter, ‘Using the Peer Effect in Scheduling and Pricing Electric Vehicles Recharging...
Comparative Analysis of Apicoplast-Targeted Protein Extension Lengths in Apicomplexan Parasites.
Seliverstov, Alexandr V; Zverkov, Oleg A; Istomina, Svetlana N; Pirogov, Sergey A; Kitsis, Philip S
2015-01-01
In general, the mechanism of protein translocation through the apicoplast membrane requires a specific extension of a functionally important region of the apicoplast-targeted proteins. The corresponding signal peptides were detected in many apicomplexans but not in the majority of apicoplast-targeted proteins in Toxoplasma gondii. In T. gondii signal peptides are either much diverged or their extension region is processed, which in either case makes the situation different from other studied apicomplexans. We propose a statistic method to compare extensions of the functionally important regions of apicoplast-targeted proteins. More specifically, we provide a comparison of extension lengths of orthologous apicoplast-targeted proteins in apicomplexan parasites. We focus on results obtained for the model species T. gondii, Neospora caninum, and Plasmodium falciparum. With our method, cross species comparisons demonstrate that, in average, apicoplast-targeted protein extensions in T. gondii are 1.5-fold longer than in N. caninum and 2-fold longer than in P. falciparum. Extensions in P. falciparum less than 87 residues in size are longer than the corresponding extensions in N. caninum and, reversely, are shorter if they exceed 88 residues.
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A. V. Khohlov
2016-01-01
Full Text Available The article analyses a one-dimensional linear integral constitutive equation of viscoelasticity with an arbitrary creep compliance function in order to reveal its abilities to describe the set of basic rheological phenomena pertaining to viscoelastoplastic materials at a constant temperature. General equations and basic properties of its quasi-static theoretic curves (i.e. stress-strain curves at constant strain or stress rates, creep, creep recovery, creep curves at piecewise-constant stress and ramp relaxation curves generated by the linear constitutive equation are derived and studied analytically. Their dependences on a creep function and relaxation modulus and on the loading program parameters are examined.The qualitative properties of the theoretic curves are compared to the typical properties of viscoelastoplastic materials test curves to reveal the mechanical effects, which the linear viscoelasticity theory cannot simulate and to find out convenient experimental indicators marking the field of its applicability or non-applicability. The minimal set of general restrictions that should be imposed on a creep and relaxation functions to provide an adequate description of typical test curves of viscoelastoplastic materials is formulated. It is proved, in particular, that an adequate simulation of typical experimental creep recovery curves requires that the derivative of a creep function should not increase at any point. This restriction implies that the linear viscoelasticity theory yields theoretical creep curves with non-increasing creep rate only and it cannot simulate materials demonstrating an accelerated creep stage. It is also proved that the linear viscoelasticity cannot simulate materials with experimental stress-strain curves possessing a maximum point or concave-up segment and materials exhibiting equilibrium modulus dependence on the strain rate or negative rate sensitivity.Similar qualitative analysis seems to be an important
Theoretical study of precision and accuracy of strain analysis by nano-beam electron diffraction
Energy Technology Data Exchange (ETDEWEB)
Mahr, Christoph, E-mail: mahr@ifp.uni-bremen.de; Müller-Caspary, Knut; Grieb, Tim; Schowalter, Marco; Mehrtens, Thorsten; Krause, Florian F.; Zillmann, Dennis; Rosenauer, Andreas
2015-11-15
Measurement of lattice strain is important to characterize semiconductor nanostructures. As strain has large influence on the electronic band structure, methods for the measurement of strain with high precision, accuracy and spatial resolution in a large field of view are mandatory. In this paper we present a theoretical study of precision and accuracy of measurement of strain by convergent nano-beam electron diffraction. It is found that the accuracy of the evaluation suffers from halos in the diffraction pattern caused by a variation of strain within the area covered by the focussed electron beam. This effect, which is expected to be strong at sharp interfaces between materials with different lattice plane distances, will be discussed for convergent-beam electron diffraction patterns using a conventional probe and for patterns formed by a precessing electron beam. Furthermore, we discuss approaches to optimize the accuracy of strain measured at interfaces. The study is based on the evaluation of diffraction patterns simulated for different realistic structures that have been investigated experimentally in former publications. These simulations account for thermal diffuse scattering using the frozen-lattice approach and the modulation-transfer function of the image-recording system. The influence of Poisson noise is also investigated. - Highlights: • Theoretical study of precision and accuracy of strain analysis by nano-beam electron diffraction. • Evaluation of simulations for exact knowledge of the actual strain. • Improvement of precision using electron beam precession. • Explanation of artefacts in the measurement close to interfaces. • Theoretical solution for the improvement of the accuracy at interfaces.
Guan, Cheng; Zhang, Houjiang; Wang, Xiping; Miao, Hu; Zhou, Lujing; Liu, Fenglu
2017-01-01
Key elastic properties of full-sized wood composite panels (WCPs) must be accurately determined not only for safety, but also serviceability demands. In this study, the modal parameters of full-sized WCPs supported on four nodes were analyzed for determining the modulus of elasticity (E) in both major and minor axes, as well as the in-plane shear modulus of panels by using a vibration testing method. The experimental modal analysis was conducted on three full-sized medium-density fiberboard (MDF) and three full-sized particleboard (PB) panels of three different thicknesses (12, 15, and 18 mm). The natural frequencies and mode shapes of the first nine modes of vibration were determined. Results from experimental modal testing were compared with the results of a theoretical modal analysis. A sensitivity analysis was performed to identify the sensitive modes for calculating E (major axis: Ex and minor axis: Ey) and the in-plane shear modulus (Gxy) of the panels. Mode shapes of the MDF and PB panels obtained from modal testing are in a good agreement with those from theoretical modal analyses. A strong linear relationship exists between the measured natural frequencies and the calculated frequencies. The frequencies of modes (2, 0), (0, 2), and (2, 1) under the four-node support condition were determined as the characteristic frequencies for calculation of Ex, Ey, and Gxy of full-sized WCPs. The results of this study indicate that the four-node support can be used in free vibration test to determine the elastic properties of full-sized WCPs. PMID:28773043
Directory of Open Access Journals (Sweden)
Leo eSold
2016-02-01
Full Text Available A re-analysis is presented here of a 10-year mass balance series at Findelengletscher, a temperate mountain glacier in Switzerland. Calculating glacier-wide mass balance from the set of glaciological point balance observations using conventional approaches, such as the profile or contour method, resulted in significant deviations from the reference value given by the geodetic mass change over a five-year period. This is attributed to the sparsity of observations at high elevations and to the inability of the evaluation schemes to adequately estimate accumulation in unmeasured areas. However, measurements of winter mass balance were available for large parts of the study period from snow probings and density pits. Complementary surveys by helicopter-borne ground-penetrating radar (GPR were conducted in three consecutive years. The complete set of seasonal observations was assimilated using a distributed mass balance model. This model-based extrapolation revealed a substantial mass loss at Findelengletscher of -0.43m w.e. a^-1 between 2004 and 2014, while the loss was less pronounced for its former tributary, Adlergletscher (-0.30m w.e. a^-1. For both glaciers, the resulting time series were within the uncertainty bounds of the geodetic mass change. We show that the model benefited strongly from the ability to integrate seasonal observations. If no winter mass balance measurements were available and snow cover was represented by a linear precipitation gradient, the geodetic mass balance was not matched. If winter balance measurements by snow probings and snow density pits were taken into account, the model performance was substantially improved but still showed a significant bias relative to the geodetic mass change. Thus the excellent agreement of the model-based extrapolation with the geodetic mass change was owed to an adequate representation of winter accumulation distribution by means of extensive GPR measurements.
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Provart Nicholas J
2008-04-01
Full Text Available Abstract Background Sequencing of the first plant genomes has revealed that cytochromes P450 have evolved to become the largest family of enzymes in secondary metabolism. The proportion of P450 enzymes with characterized biochemical function(s is however very small. If P450 diversification mirrors evolution of chemical diversity, this points to an unexpectedly poor understanding of plant metabolism. We assumed that extensive analysis of gene expression might guide towards the function of P450 enzymes, and highlight overlooked aspects of plant metabolism. Results We have created a comprehensive database, 'CYPedia', describing P450 gene expression in four data sets: organs and tissues, stress response, hormone response, and mutants of Arabidopsis thaliana, based on public Affymetrix ATH1 microarray expression data. P450 expression was then combined with the expression of 4,130 re-annotated genes, predicted to act in plant metabolism, for co-expression analyses. Based on the annotation of co-expressed genes from diverse pathway annotation databases, co-expressed pathways were identified. Predictions were validated for most P450s with known functions. As examples, co-expression results for P450s related to plastidial functions/photosynthesis, and to phenylpropanoid, triterpenoid and jasmonate metabolism are highlighted here. Conclusion The large scale hypothesis generation tools presented here provide leads to new pathways, unexpected functions, and regulatory networks for many P450s in plant metabolism. These can now be exploited by the community to validate the proposed functions experimentally using reverse genetics, biochemistry, and metabolic profiling.
Kuklja, M M; Kotomin, E A; Merkle, R; Mastrikov, Yu A; Maier, J
2013-04-21
Solid oxide fuel cells (SOFC) are under intensive investigation since the 1980's as these devices open the way for ecologically clean direct conversion of the chemical energy into electricity, avoiding the efficiency limitation by Carnot's cycle for thermochemical conversion. However, the practical development of SOFC faces a number of unresolved fundamental problems, in particular concerning the kinetics of the electrode reactions, especially oxygen reduction reaction. We review recent experimental and theoretical achievements in the current understanding of the cathode performance by exploring and comparing mostly three materials: (La,Sr)MnO3 (LSM), (La,Sr)(Co,Fe)O3 (LSCF) and (Ba,Sr)(Co,Fe)O3 (BSCF). Special attention is paid to a critical evaluation of advantages and disadvantages of BSCF, which shows the best cathode kinetics known so far for oxides. We demonstrate that it is the combined experimental and theoretical analysis of all major elementary steps of the oxygen reduction reaction which allows us to predict the rate determining steps for a given material under specific operational conditions and thus control and improve SOFC performance.
Online channel operation mode: Game theoretical analysis from the supply chain power structure
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Song Huang
2015-11-01
Full Text Available Purpose: Dual-channels have been widely used in practice, and the pricing decisions and the online channel operation mode choice have been the core problems in dual-channel supply chain management. This paper focuses on the online channel operation mode choice from the supply chain power structures based on game theoretical analysis. Design/methodology/approach: This paper utilizes three kinds of game theoretical models to analyze the impact of supply chain power structures on the optimal pricing and online channel operation mode choice. Findings: Results derived in this paper indicate that when the self-price elasticity is large, the power structures have no direct impact on the decisions. However, when the self-price elasticity is small and customers’ preference for the online channel is low, then in the MS market, it is better for the retailer to operate the online channel, while in the RS market or in the VN market, it is better for the manufacturer to operate the online channel. Research limitations/implications: In this paper, we do not consider stochastic demand and asymmetric information, which may not well suit the reality. Originality/value: This paper provides a different perspective to analyze the impact of supply chain power structures on the pricing decisions and online channel operation mode choice. The comparison of these two online channel operation modes in this paper is also a unique point.
Negro, Francesco; Yavuz, Ş Utku; Yavuz, Utku Ş; Farina, Dario
2014-01-01
Contractile properties of human motor units provide information on the force capacity and fatigability of muscles. The spike-triggered averaging technique (STA) is a conventional method used to estimate the twitch waveform of single motor units in vivo by averaging the joint force signal. Several limitations of this technique have been previously discussed in an empirical way, using simulated and experimental data. In this study, we provide a theoretical analysis of this technique in the frequency domain and describe its intrinsic limitations. By analyzing the analytical expression of STA, first we show that a certain degree of correlation between the motor unit activities prevents an accurate estimation of the twitch force, even from relatively long recordings. Second, we show that the quality of the twitch estimates by STA is highly related to the relative variability of the inter-spike intervals of motor unit action potentials. Interestingly, if this variability is extremely high, correct estimates could be obtained even for high discharge rates. However, for physiological inter-spike interval variability and discharge rate, the technique performs with relatively low estimation accuracy and high estimation variance. Finally, we show that the selection of the triggers that are most distant from the previous and next, which is often suggested, is not an effective way for improving STA estimates and in some cases can even be detrimental. These results show the intrinsic limitations of the STA technique and provide a theoretical framework for the design of new methods for the measurement of motor unit force twitch.
Institute of Scientific and Technical Information of China (English)
WANG Xin-jie; BAI Shao-xian; HUANG Ping
2006-01-01
A new mathematical model for thin film lubrication is established by taking into account the effect of an electric double layer.In the present paper,experiments are carried out on a self-made tester.With a composite block and a rotating disk,influence of electric double layer on thin film lubrication is studied.Two different methods are used to reconstruct the field of electric double layer so as to change its effect.One is to change the ionic concentration of lubricants by adding additives,and the other is to apply an external electric field on friction pairs.According theoretical analysis,both the methods will apparently change the electro-viscosity of the lubricant film so as to change the lubrication performances.After theoretical calculation of electro-viscosity is amended according to the experimental results,the equations of electro-viscosity are presented.The results show that the equivalent viscosity of fluid induced by the effect of electric double layer apparently increases with the decrease of thickness of the film while the lubrication film is thin enough.The effect of electro-viscosity is weakened as the thickness of the film increases.Moreover,the effect of electro-viscosity increases with the increase of external electric field at first.When the voltage reaches a certain value,the electro-viscosity begins to decrease.
Directory of Open Access Journals (Sweden)
Shymanska K.V.
2017-03-01
Full Text Available The need for transformation of Ukraine's migration policy based on globalized world development trends and in response to the challenges of European integration transformations causes the need of researching the theoretical and methodological basis of migration studies, and the regulations of existing theories of international migration. The bibliometric analysis of scientific publications on international migration in cites indexes found that the recent researches on these problems acquire interdisciplinary character. It necessitates the transformation of migration study approaches basing on economic, social, institutional theories and concepts synthesis. The article is devoted to the study of theoretical regulations of existing international migration theories in the context of the evolution of scientists’ views on this phenomenon. The author found that the existing theories of international migration should be divided into three categories (microeconomic, macroeconomic, globalizational that contributes to their understanding in the context of implementation possibilities in migrational public administration practice. It allows to determine the theories which should be used for Ukrainian state migration policy constructing and eliminating or reducing the external migration negative effects.
A framework for biodynamic feedthrough analysis--part I: theoretical foundations.
Venrooij, Joost; van Paassen, Marinus M; Mulder, Mark; Abbink, David A; Mulder, Max; van der Helm, Frans C T; Bulthoff, Heinrich H
2014-09-01
Biodynamic feedthrough (BDFT) is a complex phenomenon, which has been studied for several decades. However, there is little consensus on how to approach the BDFT problem in terms of definitions, nomenclature, and mathematical descriptions. In this paper, a framework for biodynamic feedthrough analysis is presented. The goal of this framework is two-fold. First, it provides some common ground between the seemingly large range of different approaches existing in the BDFT literature. Second, the framework itself allows for gaining new insights into BDFT phenomena. It will be shown how relevant signals can be obtained from measurement, how different BDFT dynamics can be derived from them, and how these different dynamics are related. Using the framework, BDFT can be dissected into several dynamical relationships, each relevant in understanding BDFT phenomena in more detail. The presentation of the BDFT framework is divided into two parts. This paper, Part I, addresses the theoretical foundations of the framework. Part II, which is also published in this issue, addresses the validation of the framework. The work is presented in two separate papers to allow for a detailed discussion of both the framework's theoretical background and its validation.
A theoretical analysis of parity violation induced by neutral currents in atomic cesium
Bouchiat, C.; Piketty, C. A.; Pignon, D.
1983-07-01
In this paper we give a theoretical analysis of the parity violation phenomena in nS - n'S transitions in atomic cesium induced by the electron-nucleus neutral-current interaction. The actual observation of parity violation consists in the measurement of an interference between the p.v. electric dipole amplitude Elpv with the electric amplitude induced by a static electric field. Our theoretical work must then include a calculation of the diagonal and non-diagonal polarizabilities of the states of atomic cesium. We have used a one-electron model proposed by Norcross which incorporates some many-body effects like the electric screening induced by the core polarization in a semi-empirical way. Our calculated values of the diagonal and non-diagonal polarizabilities of the nS states are in good agreement with the existing measurements; this confirms the already well-established success of the model in predicting the radiative transitions in cesium. We present theoretical arguments supported by detailed numerical computations showing that the one-particle matrix element of the parity-violating electron-nucleus interaction and the parity-violating electric dipole amplitude Elpv itself weakly depend on the shape of the one-electron potential provided the binding energies of the valence states are reproduced accurately. Furthermore it turns out that because of a compensation mechanism, the parity-violating transition is induced by the radiation field outside the ion core region where the screening can be described simply in terms of the measurable cesium ion polarizability. Our results are then used to extract, from the Ecole Normale Supérieure experiment, a value of the weak charge Qw = -57.1 ± 9.4 (r.m.s. statistical deviation) ± 4.7 (systematic uncertainty). This number is to be compared with the prediction of the Weinberg-Salam model with electro-weak radiative corrections: Qw = -68.6 ± 3.0. A general discussion of the uncertainties of the atomic physics
Pradipta, R.; Lee, M. C.
2013-07-01
We have been investigating high-power radio wave-induced acoustic gravity waves (AGWs) at Gakona, Alaska, using the High-frequency Active Aurora Research Program (HAARP) heating facility (i.e. HF heater) and extensive diagnostic instruments. This work was aimed at performing a controlled study of the space plasma turbulence triggered by the AGWs originating from anomalous heat sources, as observed in our earlier experiments at Arecibo, Puerto Rico (Pradipta 2007 MS Thesis MIT Press, Cambridge, MA). The HF heater operated in continuous wave (CW) O-mode can heat ionospheric plasmas effectively to yield a depleted magnetic flux tube as rising plasma bubbles (Lee et al 1998 Geophys. Res. Lett. 25 579). Two processes are responsible for the depletion of the magnetic flux tube: (i) thermal expansion and (ii) chemical reactions caused by heated ions. The depleted plasmas create large density gradients that can augment spread F processes via generalized Rayleigh-Taylor instabilities (Lee et al 1999 Geophys. Res. Lett. 26 37). It is thus expected that the temperature of neutral particles in the heated ionospheric region can be increased. Such a heat source in the neutral atmosphere may potentially generate AGWs in the form of traveling ionospheric plasma disturbances (TIPDs). We should point out that these TIPDs have features distinctively different from electric and magnetic field (ExB) drifts of HF wave-induced large-scale non-propagating plasma structures. Moreover, it was noted in our recent study of naturally occurring AGW-induced TIDs that only large-scale AGWs can propagate upward to reach higher altitudes. Thus, in our Gakona experiments we select optimum heating schemes for HF wave-induced AGWs that can be distinguished from the naturally occurring ones. The generation and propagation of AGWs are monitored by MUIR (Modular Ultra high-frequency Ionospheric Radar), Digisonde and GPS/low-earth-orbit satellites. Our theoretical and experimental studies have shown that
Road safety risk evaluation and target setting using data envelopment analysis and its extensions.
Shen, Yongjun; Hermans, Elke; Brijs, Tom; Wets, Geert; Vanhoof, Koen
2012-09-01
Currently, comparison between countries in terms of their road safety performance is widely conducted in order to better understand one's own safety situation and to learn from those best-performing countries by indicating practical targets and formulating action programmes. In this respect, crash data such as the number of road fatalities and casualties are mostly investigated. However, the absolute numbers are not directly comparable between countries. Therefore, the concept of risk, which is defined as the ratio of road safety outcomes and some measure of exposure (e.g., the population size, the number of registered vehicles, or distance travelled), is often used in the context of benchmarking. Nevertheless, these risk indicators are not consistent in most cases. In other words, countries may have different evaluation results or ranking positions using different exposure information. In this study, data envelopment analysis (DEA) as a performance measurement technique is investigated to provide an overall perspective on a country's road safety situation, and further assess whether the road safety outcomes registered in a country correspond to the numbers that can be expected based on the level of exposure. In doing so, three model extensions are considered, which are the DEA based road safety model (DEA-RS), the cross-efficiency method, and the categorical DEA model. Using the measures of exposure to risk as the model's input and the number of road fatalities as output, an overall road safety efficiency score is computed for the 27 European Union (EU) countries based on the DEA-RS model, and the ranking of countries in accordance with their cross-efficiency scores is evaluated. Furthermore, after applying clustering analysis to group countries with inherent similarity in their practices, the categorical DEA-RS model is adopted to identify best-performing and underperforming countries in each cluster, as well as the reference sets or benchmarks for those
Calloway, Pauline Frances
This study investigated the construct validity of the Herzberg (1964) theory of motivation as it relates to county Extension agents; and developed an inventory to measure the job satisfaction of county agents in North Carolina. The inventory was administered to 419 agents in 79 counties. Factor analysis was used to determine the number of job…
Du, Hong-Gen; Liao, Sheng-Hui; Jiang, Zhong; Huang, Huan-Ming; Ning, Xi-Tao; Jiang, Neng-Yi; Pei, Jian-Wei; Huang, Qin; Wei, Hui
2016-05-01
This study investigates the effect of a new Chinese massage technique named "press-extension" on degenerative lumbar with disc herniation and facet joint dislocation, and provides a biomechanical explanation of this massage technique. Self-developed biomechanical software was used to establish a normal L1-S1 lumbar 3D FE model, which integrated the spine CT and MRI data-based anatomical structure. Then graphic technique is utilized to build a degenerative lumbar FE model with disc herniation and facet joint dislocation. According to the actual press-extension experiments, mechanic parameters are collected to set boundary condition for FE analysis. The result demonstrated that press-extension techniques bring the annuli fibrosi obvious induction effect, making the central nucleus pulposus forward close, increasing the pressure in front part. Study concludes that finite element modelling for lumbar spine is suitable for the analysis of press-extension technique impact on lumbar intervertebral disc biomechanics, to provide the basis for the disease mechanism of intervertebral disc herniation using press-extension technique.
Parametric Sensitivity Analysis for Stochastic Molecular Systems using Information Theoretic Metrics
Tsourtis, Anastasios; Katsoulakis, Markos A; Harmandaris, Vagelis
2014-01-01
In this paper we extend the parametric sensitivity analysis (SA) methodology proposed in Ref. [Y. Pantazis and M. A. Katsoulakis, J. Chem. Phys. 138, 054115 (2013)] to continuous time and continuous space Markov processes represented by stochastic differential equations and, particularly, stochastic molecular dynamics as described by the Langevin equation. The utilized SA method is based on the computation of the information-theoretic (and thermodynamic) quantity of relative entropy rate (RER) and the associated Fisher information matrix (FIM) between path distributions. A major advantage of the pathwise SA method is that both RER and pathwise FIM depend only on averages of the force field therefore they are tractable and computable as ergodic averages from a single run of the molecular dynamics simulation both in equilibrium and in non-equilibrium steady state regimes. We validate the performance of the extended SA method to two different molecular stochastic systems, a standard Lennard-Jones fluid and an al...
A THEORETICAL ANALYSIS OF KEY POINTS WHEN CHOOSING OPEN SOURCE ERP SYSTEMS
Directory of Open Access Journals (Sweden)
Fernando Gustavo Dos Santos Gripe
2011-08-01
Full Text Available The present work is aimed at presenting a theoretical analysis of the main features of Open Source ERP systems, herein identified as success technical factors, in order to contribute to the establishment of parameters to be used in decision-making processes when choosing a system which fulfills the organization´s needs. Initially, the life cycle of ERP systems is contextualized, highlighting the features of Open Source ERP systems. As a result, it was verified that, when carefully analyzed, these systems need further attention regarding issues of project continuity and maturity, structure, transparency, updating frequency, and support, all of which are inherent to the reality of this type of software. Nevertheless, advantages were observed in what concerns flexibility, costs, and non-discontinuity as benefits. The main goal is to broaden the discussion about the adoption of Open Source ERP systems.
Experimental and theoretical analysis of vortex breakdown in the wake of the 25∘ Ahmed body
Jermann, Cyril; Meliga, Philippe; Pujals, Gregory; Gallaire, Francois; Serre, Eric
2014-11-01
We study experimentally and theoretically the wake of the 25circ; Ahmed body, considered a suitable test-case to reproduce the two counter-rotating longitudinal vortices widely encountered in automotive aerodynamics. The three-dimensional experimental mean flow is reconstructed at high Reynolds number (Re = 2 . 8 ×106) from a series of cross-flow time-averaged planes acquired with a moving automated Stereo-PIV system. We observe a sharp decay of the axial velocity and vorticity in the near-wake, 0 . 5 times the projected length of the slanted surface downstream the square back, where the streamwise vortices is subjected to a strong adverse pressure gradient and the turbulent kinetic energy exhibits a peak in the vortex core. A stability analysis of the experimental velocity shows that the flow undergoes vortex breakdown roughly at the same position, through a transition from supercritical (x 0 . 5) conditions and the accumulation of upstream propagating axisymmetric waves.
Xiao, Chunyan; Rubinsky, Boris
2014-12-01
An analytical model was used to explore the feasibility of sinusoidal electric field transmission across a frozen saline layer into biological tissue. The study is relevant to electroporation and permeabilization of the cell membrane by electric fields. The concept was analyzed for frequencies in the range of conventional electroporation frequencies and electric field intensity. Theoretical analysis for a variety of tissues show that the transmission of electroporation type electric fields through a layer of frozen saline into tissue is feasible and the behavior of this composite system depends on tissue type, frozen domain temperature, and frequency. Freezing could become a valuable method for adherence of electroporation electrodes to moving tissue surfaces, such as the heart in the treatment of atrial fibrillation or blood vessels for the treatment of restenosis.
Theoretical analysis of electronic absorption spectra of vitamin B12 models
Andruniow, Tadeusz; Kozlowski, Pawel M.; Zgierski, Marek Z.
2001-10-01
Time-dependent density-functional theory (TD-DFT) is applied to analyze the electronic absorption spectra of vitamin B12. To accomplish this two model systems were considered: CN-[CoIII-corrin]-CN (dicyanocobinamide, DCC) and imidazole-[CoIII-corrin]-CN (cyanocobalamin, ImCC). For both models 30 lowest excited states were calculated together with transition dipole moments. When the results of TD-DFT calculations were directly compared with experiment it was found that the theoretical values systematically overestimate experimental data by approximately 0.5 eV. The uniform adjustment of the calculated transition energies allowed detailed analysis of electronic absorption spectra of vitamin B12 models. All absorption bands in spectral range 2.0-5.0 eV were readily assigned. In particular, TD-DFT calculations were able to explain the origin of the shift of the lowest absorption band caused by replacement of the-CN axial ligand by imidazole.
The structure and dynamics of cities urban data analysis and theoretical modeling
Barthelemy, Marc
2016-01-01
With over half of the world's population now living in urban areas, the ability to model and understand the structure and dynamics of cities is becoming increasingly valuable. Combining new data with tools and concepts from statistical physics and urban economics, this book presents a modern and interdisciplinary perspective on cities and urban systems. Both empirical observations and theoretical approaches are critically reviewed, with particular emphasis placed on derivations of classical models and results, along with analysis of their limits and validity. Key aspects of cities are thoroughly analyzed, including mobility patterns, the impact of multimodality, the coupling between different transportation modes, the evolution of infrastructure networks, spatial and social organisation, and interactions between cities. Drawing upon knowledge and methods from areas of mathematics, physics, economics and geography, the resulting quantitative description of cities will be of interest to all those studying and r...
Theoretical analysis of harmonic suppression in multi-step error separation technique
Gu, Wei; Tan, Jiubin; Huang, Jingzhi
2015-02-01
Multi-step error separation technique is one of the most widely used roundness separation technique. It can improve the precision of the roundness measuring instrument. By analyzing the model of multi-step, we can find that it has harmonic suppression and cannot be completely separate the roundness error of the tested parts from the rotation error of the spindle. When we use the M-steps, the km times harmonic in tested parts is lost and is mixed 1:1 with the rotation error of the spindle. In this paper, theoretical provement and simulation analysis of harmonic suppression of multi-step error separation technique are carried out: 1) using a group circular standards to separate the same spindle; and 2) using different steps to separate the same spindle.
Institute of Scientific and Technical Information of China (English)
Huo Rui; Shi Yin
2005-01-01
In view of difficulties concerned with direct measurement of excitations inside source equipments and their significant influence on vibration isolation effectiveness, a dynamical model, for vibration isolation of a rigid machine with six-degree-of-freedom mounted on a flexible foundation through multiple mounts, is analyzed, in which the complicated and multiple disturbances inside the machine are described as an equivalent excitation spectrum. And a method for the estimation of the equivalent excitation spectrum according to system dynamic responses is discussed for the quantitative prediction of isolation effectiveness.Both theoretical analysis and experimental results are demonstrated. Further work shows the quantitative prediction of transmitted power flow in a flexible vibration isolation experiment system using the proposed equivalent excitation spectrum method, by comparison with its testing results.
Theoretical analysis on shear-bending deflection of a ring-shape piezoelectric plate
Directory of Open Access Journals (Sweden)
Zejun Yu
2016-02-01
Full Text Available In this paper, the electromechanical coupling field in shear-bending mode for a ring-shape piezoelectric plate was theoretically established. According to the classical small bending elastic plate theory and piezoelectric constitutive equations, the analytical solution to the bending deformation of the piezo-actuator under electric field and a concentrated or uniformly distributed mechanical load was achieved. The mechanism for generating bending deformation is attributed to axisymmetric shear strain, which further induces the bending deformation of the single ring-shape piezoelectric plate. This mechanism is significant different from that of piezoelectric bimorph or unimorph actuators reported before. Our analysis offers guidance for the optimum design of a ring-shape shear-bending piezo-actuator.
Institute of Scientific and Technical Information of China (English)
无
2002-01-01
Based on pair potential, the Bragg Williams (B-W) model is modified to take into account the effect of the lattice parameter on theoretical order-disorder transformation analysis. The main purpose of this work is to understand the basic aspects of this effect and related reasonable model on order-disorder transformation. In the present approach, the configuration free energy is chosen as function of the lattice parameter and the long-range order. This energy is calculated through Taylor's expansion, starting from the disordered state. It was found that the configuration free energy has been strongly modified when the lattice parameter is taken into account. It was also found only one type of order-disorder transformation exists in AB alloy and three kinds of order-disorder transformations for non-equiatomic alloy system such as A3B alloy. This result is in agreement with experiments.
Sebai, Jihane
2016-01-01
Various organizational, functional or structural issues have led to a review of the foundations of the former health care system based on a traditional market segmentation between general practice and hospital medicine, and between health and social sectors and marked by competition between private and public sectors. The current reconfiguration of the health care system has resulted in “new” levers explained by the development of a new organizational reconfiguration of the primary health care model. Coordinated care structures (SSC) have been developed in this context by making coordination the cornerstone of relations between professionals to ensure global, continuous and quality health care. This article highlights the contributions of various theoretical approaches to the understanding of the concept of coordination in the analysis of the current specificity of health care.
Theoretical analysis for the specific heat and thermal parameters of solid C60
Soto, J. R.; Calles, A.; Castro, J. J.
1997-08-01
We present the results of a theoretical analysis for the thermal parameters and phonon contribution to the specific heat in solid C60. The phonon contribution to the specific heat is calculated through the solution of the corresponding dynamical matrix, for different points in the Brillouin zone, and the construccion of the partial and generalized phonon density of states. The force constants are obtained from a first principle calculation, using a SCF Hartree-Fock wave function from the Gaussian 92 program. The thermal parameters reported are the effective temperatures and vibrational amplitudes as a function of temperature. Using this model we present a parametization scheme in order to reproduce the general behaviour of the experimental specific heat for these materials.
Directory of Open Access Journals (Sweden)
Peng Hu
2017-02-01
Full Text Available Electrothermal energy storage (ETES provides bulk electricity storage based on heat pump and heat engine technologies. A subcritical ETES is described in this paper. Based on the extremum principle of entransy dissipation, a geometry model is developed for heat transfer optimization for subcritical ETES. The exergy during the heat transfer process is deduced in terms of entropy production. The geometry model is validated by the extremum principle of entropy production. The theoretical analysis results show that the extremum principle of entransy dissipation is an effective criterion for the optimization, and the optimum heat transfer for different cases with the same mass flux or pressure has been discussed. The optimum heat transfer can be achieved by adjusting the mass flux and pressure of the working fluid. It also reveals that with the increase of mass flux, there is a minimum exergy in the range under consideration, and the exergy decreases with the increase of the pressure.
A theoretical analysis of optical-to-THz conversion efficiency via optical rectification
Institute of Scientific and Technical Information of China (English)
2008-01-01
A theoretical analysis of an ultra-short pulse converted to Terahertz radiation via optical rectification in nonlinear optical crystal is presented here;several factors that affect optical-to-THz conversion efficiencies are discussed;pulse durations affect the conversion efficiency effectively:when crystal length is equal to the optimal crystal length lc,optical-to-THz conversion efficiency is the highest,but for the periodically-inverted electro-optic crystals,conversion efficiency is almost proportional to the crystal length when absorption can be neglected.Taking account of the absorption of crystals,effective length of crystal is Leff=0.63/α,there is no apparent increase of conversion efficiency and the conversion efficiency approaches to a constant eventually when the crystal length is increased.
Theoretical analysis of nanoparticle-induced homeotropic alignment in nematic liquid crystals
Choudhary, Amit; Li, Guoqiang
2015-01-01
A theoretical analysis of homeotropic alignment induced by nanoparticles (NPs) in a nematic liquid crystal (NLC) sample cell is presented. It is found that such alignment on the surface of a NP causes a change in the orientation of the molecular director near the surface, which in turn induces variations in the elastic constants and free energy. The induced NLC properties allow coupling between nearby NPs, mediated by the NLC molecules. The rotation of the coupled NPs close to the substrate tends to induce a long-range orientation of the NLC molecular director, leading to modification in the alignment at the interface of NLC and substrate which induces the orientation from homogeneous (planar) to homeotropic (vertical) in the bulk material.
Dirba, I.; Kleperis, J.
2011-01-01
Analytical and numerical modelling is performed for the linear actuator of a parallel path magnet motor. In the model based on finite-element analysis, the 3D problem is reduced to a 2D problem, which is sufficiently precise in a design aspect and allows modelling the principle of a parallel path motor. The paper also describes a relevant numerical model and gives comparison with experimental results. The numerical model includes all geometrical and physical characteristics of the motor components. The magnetic flux density and magnetic force are simulated using FEMM 4.2 software. An experimental model has also been developed and verified for the core of switchable magnetic flux linear actuator and motor. The results of experiments are compared with those of theoretical/analytical and numerical modelling.
Directory of Open Access Journals (Sweden)
Mohammad Jebran Khan
2015-04-01
Full Text Available Gears or toothed wheels form a positive drive for power transmission system in precision machines wherein a definite velocity ratio is needed. Despite having high cost, complicated manufacturing, need of precise alignment of shafts and lubrication, the gear drives are preferred over other power transmission drives. One of the important reasons of preference being that of efficiency which is very high in gear drives, even upto 99 per cent in case of spur gears. Spur gears are the simplest of the gear drives having teeth cut parallel to the axis of the shaft. Herein, we report the contact stress analysis of Stainless Steel spur gears by theoretical method using Hertz equations and by Finite Element Analysis using FEA software ANSYS 14.0 Workbench. The spur gear is sketched and modelled in ANSYS Design Modeller and the contact stress analysis is done in Mechanical ANSYS Multiphysics. When compared, the results of both theoretical method and FEA show a good degree of agreement with each other.
Tanabe, Hideaki; Otsuka, Kuniko; Otsuka, Makoto
2007-07-01
In order to clarify the theoretical basis of the variability in the measurement of tablet hardness by compression pressure, NIR spectroscopic methods were used to predict tablet hardness of the formulations. Tablets (200 mg, 8 mm in diameter) consisting of berberine chloride, lactose, and potato starch were formed at various compression pressures (59, 78, 98, 127, 195 MPa). The hardness and the distribution of micropores were measured. The reflectance NIR spectra of various compressed tablets were used as a calibration set to establish a calibration model to predict tablet hardness by principal component regression (PCR) analysis. The distribution of micropores was shifted to a smaller pore size with increasing compression pressure. The total pore volume of tablets decreased as the compression pressure increased. The hardness increased as the compression pressure increased. The hardness could be predicted using a calibration model consisting of 7 principal components (PCs) obtained by PCR. The relationship between the predicted and the actual hardness values exhibited a straight line, an R(2) of 0.925. In order to understand the theoretical analysis (scientific background) of calibration models used to evaluate tablet hardness, the standard error of cross validation (SEV) values, the loading vectors of each PC and the regression vector were investigated. The result obtained with the calibration models for hardness suggested that the regression vector might involve physical and chemical factors. In contrast, the porosity could be predicted using a calibration model composed of 2 PCs. The relationship between the predicted and the actual total pore volume showed a straight line with R(2) = 0.801. The regression vector of the total pore volume might be due to physical factors.
Yasunaga, T; Wakabayashi, T
1996-01-01
To study macromolecular structure by electron microscopy, a highly extensible and object-oriented system has been developed for image analysis. This system is named "Eos" (Extensible and object-oriented system). The system described here supplies an environment with four types of supports: (i) a group of small tools for image analysis, (ii) tools for integration of small tools, such as "Display2," (iii) tools for development, such as "maketool," and (iv) object-oriented libraries for development of new tools. Using Eos, electron micrographs can be analyzed by small tools and integration tools. In addition, Eos can be used to develop new tools based on new ideas because development tool and object-oriented libraries are provided. The examples of implemented small tools for image analysis include three-dimensional reconstruction of objects with helical symmetry, cluster analysis, and contour expression.
Institute of Scientific and Technical Information of China (English)
YanfengCHEN; ShuishengQIU; 等
1999-01-01
An extension of characteristic equation analysis method to the stability analysis of equilibrium points for closed-loop PWM power switching converters is introduced based on equivalent small parameter method.The basic principle of the method is described in detail.The provided example shows that the method,incorporating with the system's state-plane trajectories,offers the advantages of both simplicity and practicality.
Cessation of environmentally-assisted cracking in a low-alloy steel: Theoretical analysis
Energy Technology Data Exchange (ETDEWEB)
Wire, G.L.
1997-02-01
Environmentally Assisted Cracking (EAC) can cause increases in fatigue crack growth rates of 40 to 100 times the rate in air for low alloy steels. The increased rates can lead to very large predicted crack growth. EAC is activated by a critical level of dissolved sulfides at the crack tip. Sulfide inclusions (MnS) in the steel produce corrosive sulfides in solution following exposure by a growing crack. In stagnant, low oxygen water conditions considered here, diffusion is the dominant mass transport mechanism acting to change the sulfide concentration within the crack. The average crack tip velocity is below the level required to produce the critical crack tip sulfide ion concentration required for EAC. Crack extension analyses also consider the breakthrough of large, hypothetical embedded defects with the attendant large freshly exposed sulfide inventory. Combrade et al. noted that a large inventory of undissolved metallurgical sulfides on crack flanks could trigger EAC, but did not quantify the effects. Diffusion analysis is extended herein to cover breakthrough of embedded defects with large sulfide inventories. The mass transport via diffusion is limited by the sulfide solubility. As a result, deep cracks in high sulfur steels are predicted to retain undissolved sulfides for extended but finite periods of time t{sub diss} which increase with the crack length and the metallurgical sulfide content in the steel. The analysis shows that the duration of EAC is limited to t{sub diss} providing V{sub eac}, the crack tip velocity associated with EAC is less than V{sub In}, the crack tip velocity below which EAC will not occur in an initially sulfide free crack. This condition on V{sub eac} need only be met for a short time following crack cleanup to turn off EAC. The predicted crack extension due to limited duration of EAC is a small fraction of the initial embedded defect size and would not greatly change calculated crack depths.
Maneuverability and usability analysis of three knee-extension propelled wheelchairs.
Bloswick, D S; Erickson, J; Brown, D R; Howell, G; Mecham, W
The purpose of this study was to evaluate the maneuverability and usability of three knee-extension propelled wheelchairs. The maneuverability of the knee-extension propelled wheelchairs was determined in a controlled test representing five standard wheelchair activities. The usability of the wheelchairs was evaluated in a field test with elderly residents of an extended care facility in Salt Lake City. The results indicate that the wheelchair designs using a swinging (four-bar linkage) or sliding belt mechanism are preferred to a sliding plate design. The use of knee-extension propelled wheelchairs is a feasible alternative to hand propelled wheelchairs. Further development and research is needed to address power requirements, maneuverability, and entrance/egress from the chairs.
Extensions of indication throughout the drug product lifecycle: a quantitative analysis.
Langedijk, Joris; Whitehead, Christopher J; Slijkerman, Diederick S; Leufkens, Hubert G M; Schutjens, Marie-Hélène D B; Mantel-Teeuwisse, Aukje K
2016-02-01
The marketing authorisation of the first generic product version is an important moment in a drug product lifecycle. The subsequently changed intellectual property protection prospects could affect the incentives for further drug development. We assessed the quantity and nature of extensions of indication of small molecule medicinal products authorised through the European Medicines Agency throughout the drug product lifecycle with special attention for the impact of the introduction of a first generic competitor. The majority (92.5%) of the extensions of indication was approved during the exclusivity period of the innovator product. Regulatory rethinking might be needed for a sustainable stimulation of extensions of indications in the post-generic period of a drug product lifecycle.
Rajalakshmi, Gnanasekaran; Hathwar, Venkatesha R; Kumaradhas, Poomani
2014-04-01
Isoniazid (isonicotinohydrazide) is an important first-line antitubercular drug that targets the InhA enzyme which synthesizes the critical component of the mycobacterial cell wall. An experimental charge-density analysis of isoniazid has been performed to understand its structural and electronic properties in the solid state. A high-resolution single-crystal X-ray intensity data has been collected at 90 K. An aspherical multipole refinement was carried out to explore the topological and electrostatic properties of the isoniazid molecule. The experimental results were compared with the theoretical charge-density calculations performed using CRYSTAL09 with the B3LYP/6-31G** method. A topological analysis of the electron density reveals that the Laplacian of electron density of the N-N bond is significantly less negative, which indicates that the charges at the b.c.p. (bond-critical point) of the bond are least accumulated, and so the bond is considered to be weak. As expected, a strong negative electrostatic potential region is present in the vicinity of the O1, N1 and N3 atoms, which are the reactive locations of the molecule. The C-H···N, C-H···O and N-H···N types of intermolecular hydrogen-bonding interactions stabilize the crystal structure. The topological analysis of the electron density on hydrogen bonding shows the strength of intermolecular interactions.
Transient Side Load Analysis of Out-of-Round Film-Cooled Nozzle Extensions
Wang, Ten-See; Lin, Jeff; Ruf, Joe; Guidos, Mike
2012-01-01
There was interest in understanding the impact of out-of-round nozzle extension on the nozzle side load during transient startup operations. The out-of-round nozzle extension could be the result of asymmetric internal stresses, deformation induced by previous tests, and asymmetric loads induced by hardware attached to the nozzle. The objective of this study was therefore to computationally investigate the effect of out-of-round nozzle extension on the nozzle side loads during an engine startup transient. The rocket engine studied encompasses a regeneratively cooled chamber and nozzle, along with a film cooled nozzle extension. The computational methodology is based on an unstructured-grid, pressure-based computational fluid dynamics formulation, and transient inlet boundary flow properties derived from an engine system simulation. Six three-dimensional cases were performed with the out-of-roundness achieved by three different degrees of ovalization, elongated on lateral y and z axes: one slightly out-of-round, one more out-of-round, and one significantly out-of-round. The results show that the separation line jump was the primary source of the peak side loads. Comparing to the peak side load of the perfectly round nozzle, the peak side loads increased for the slightly and more ovalized nozzle extensions, and either increased or decreased for the two significantly ovalized nozzle extensions. A theory based on the counteraction of the flow destabilizing effect of an exacerbated asymmetrical flow caused by a lower degree of ovalization, and the flow stabilizing effect of a more symmetrical flow, created also by ovalization, is presented to explain the observations obtained in this effort.
Literatura analysis of design approach in extensions on Early Modern building
Directory of Open Access Journals (Sweden)
Kuzović Duško
2015-01-01
Full Text Available Extension on objects built in the spirit of early modern in western Serbia began in 1953. As a basis, architects have had an object whose architectural language was familiar. Architect formed superstructure in the spirit of modern architecture and by using well known language elements. However, despite the identical language of the old and new building part there showed certain misunderstanding with basic shaping principles and goals applied by previous architect. Such misunderstandings rarely came across during extensions performed during 19th century. This paper analyzes several examples built and upgraded during the first half of the 20th century in Uzice.
1979-01-01
Cost scheduling and funding data are presented for the reference design of the power extension package. Major schedule milestones are correlated with current Spacelab flight dates. Funding distributions provide for minimum expenditure during the first year of the project.
Extensions of indication throughout the drug product lifecycle: a quantitative analysis
Langedijk, Joris; Whitehead, Christopher J; Slijkerman, Diederick S; Leufkens, Hubert G M; Schutjens, Marie-Hélène D B; Mantel-Teeuwisse, Aukje K
2016-01-01
The marketing authorisation of the first generic product version is an important moment in a drug product lifecycle. The subsequently changed intellectual property protection prospects could affect the incentives for further drug development. We assessed the quantity and nature of extensions of indi
Using R-Project for Free Statistical Analysis in Extension Research
Mangiafico, Salvatore S.
2013-01-01
One option for Extension professionals wishing to use free statistical software is to use online calculators, which are useful for common, simple analyses. A second option is to use a free computing environment capable of performing statistical analyses, like R-project. R-project is free, cross-platform, powerful, and respected, but may be…
Extensions of indication throughout the drug product lifecycle: a quantitative analysis
Langedijk, Joris; Whitehead, Christopher J; Slijkerman, Diederick S; Leufkens, Hubert G M; Schutjens, Marie-Hélène D B; Mantel-Teeuwisse, Aukje K
The marketing authorisation of the first generic product version is an important moment in a drug product lifecycle. The subsequently changed intellectual property protection prospects could affect the incentives for further drug development. We assessed the quantity and nature of extensions of
An Analysis of "In-Depth" Schools Conducted by Area Extension Agents in the Agricultural Industry.
Cunningham, Clarence J.
The Ohio Extension Service conducted "in-depth" schools on Dairy Genetics and Reproduction, Beef Cattle, Capital Management, and Fertilizer and Lime at area centers in Wooster, Defiance and Fremont, Washington Court House, and McConnellsville. Two thirds of the instructional staff were area agents; others were specialists, resident…
Rabosky, Daniel L; Mitchell, Jonathan S; Chang, Jonathan
2017-07-01
Bayesian analysis of macroevolutionary mixtures (BAMM) is a statistical framework that uses reversible jump Markov chain Monte Carlo to infer complex macroevolutionary dynamics of diversification and phenotypic evolution on phylogenetic trees. A recent article by Moore et al. (MEA) reported a number of theoretical and practical concerns with BAMM. Major claims from MEA are that (i) BAMM's likelihood function is incorrect, because it does not account for unobserved rate shifts; (ii) the posterior distribution on the number of rate shifts is overly sensitive to the prior; and (iii) diversification rate estimates from BAMM are unreliable. Here, we show that these and other conclusions from MEA are generally incorrect or unjustified. We first demonstrate that MEA's numerical assessment of the BAMM likelihood is compromised by their use of an invalid likelihood function. We then show that "unobserved rate shifts" appear to be irrelevant for biologically plausible parameterizations of the diversification process. We find that the purportedly extreme prior sensitivity reported by MEA cannot be replicated with standard usage of BAMM v2.5, or with any other version when conventional Bayesian model selection is performed. Finally, we demonstrate that BAMM performs very well at estimating diversification rate variation across the ${\\sim}$20% of simulated trees in MEA's data set for which it is theoretically possible to infer rate shifts with confidence. Due to ascertainment bias, the remaining 80% of their purportedly variable-rate phylogenies are statistically indistinguishable from those produced by a constant-rate birth-death process and were thus poorly suited for the summary statistics used in their performance assessment. We demonstrate that inferences about diversification rates have been accurate and consistent across all major previous releases of the BAMM software. We recognize an acute need to address the theoretical foundations of rate-shift models for
Theoretical analysis of parity violation induced by neutral currents in atomic cesium
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Bouchiat, C.; Piketty, C.A.; Pignon, D. (Ecole Normale Superieure, 75 - Paris (France). Lab. de Physique Theorique)
1983-07-04
In this paper we give a theoretical analysis of the parity violation phenomena in nS-n'S transitions in atomic cesium induced by the electron-nucleus neutral-current interaction. The actual observation of parity violation consists in the measurement of an interference between the p.v. electric dipole amplitude E/sub 1/sup(pv) with the electric amplitude induced by a static electric field. Our theoretical work must then include a calculation of the diagonal and non-diagonal polarizabilities of the states of atomic cesium. We have used a one-electron model proposed by Norcross which incorporates some many-body effects like the electric screening induced by the core polarization in a semi-empirical way. Our calculated values of the diagonal and non-diagonal polarizabilities of the nS states are in good agreement with the existing measurements; this confirms the already well-established success of the model in predicting the radiative transitions in cesium. We present theoretical arguments supported by detailed numerical computations showing that the one-particle matrix element of the parity-violating electron-nucleus interaction and the parity-violating electric dipole amplitude E/sub 1/sup(pv) itself weakly depend on the shape of the one-electron potential provided the binding energies of the valence states are reproduced accurately. Furthermore it turns out that because of a compensation mechanism, the parity-violating transition is induced by the radiation field outside the ion core region where the screening can be described simply in terms of the measurable cesium ion polarizability. Our results are then used to extract, from the Ecole Normale Superieure experiment, a value of the weak charge Qsub(w)= -57.1+-9.4 (r.m.s. statistical deviation) +-4.7 (systematic uncertainty). This number is to be compared with the prediction of the Weinberg-Salam model with electro-weak radiative corrections: Qsub(w)=-68.6+-3.0.
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Francesco Negro
Full Text Available Contractile properties of human motor units provide information on the force capacity and fatigability of muscles. The spike-triggered averaging technique (STA is a conventional method used to estimate the twitch waveform of single motor units in vivo by averaging the joint force signal. Several limitations of this technique have been previously discussed in an empirical way, using simulated and experimental data. In this study, we provide a theoretical analysis of this technique in the frequency domain and describe its intrinsic limitations. By analyzing the analytical expression of STA, first we show that a certain degree of correlation between the motor unit activities prevents an accurate estimation of the twitch force, even from relatively long recordings. Second, we show that the quality of the twitch estimates by STA is highly related to the relative variability of the inter-spike intervals of motor unit action potentials. Interestingly, if this variability is extremely high, correct estimates could be obtained even for high discharge rates. However, for physiological inter-spike interval variability and discharge rate, the technique performs with relatively low estimation accuracy and high estimation variance. Finally, we show that the selection of the triggers that are most distant from the previous and next, which is often suggested, is not an effective way for improving STA estimates and in some cases can even be detrimental. These results show the intrinsic limitations of the STA technique and provide a theoretical framework for the design of new methods for the measurement of motor unit force twitch.
Site-city interaction: theoretical, numerical and experimental crossed-analysis
Schwan, L.; Boutin, C.; Padrón, L. A.; Dietz, M. S.; Bard, P.-Y.; Taylor, C.
2016-05-01
The collective excitation of city structures by a seismic wavefield and the subsequent multiple Structure-Soil-Structure Interactions (SSSIs) between the buildings are usually disregarded in conventional seismology and earthquake engineering practice. The objective here is to qualify and quantify these complex multiple SSSIs through the design of an elementary study case, which serves as a benchmark for theoretical, numerical and experimental crossed-analysis. The experimental specimen consists of an idealized site-city setup with up to 37 anisotropic resonant structures arranged at the top surface of an elastic layer and in co-resonance with it. The experimental data from shaking table measurements is compared with the theoretical and numerical results provided respectively by an equivalent city-impedance model derived analytically from homogenization in the long-wavelength approximation and a model based on boundary elements. The signatures of the site-city interactions are identified in the frequency, time and space domain, and in particular consist of a frequency-dependent free/rigid switch in the surface condition at the city resonance, beatings in the records and the depolarization of the wavefield. A parametric study on the city density shows that multiple SSSIs among the city structures (five are sufficient) can have significant effects on both the seismic response of its implantation site and that of the buildings. Key parameters are provided to assess site-city interactions in the low seismic frequency range: They involve the mass and rigidity of the city compared to those of the soil and the damping of the building.
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Rolando Quintana Aput
2011-03-01
Full Text Available The present paper encloses the analysis of some troubles related to the development of theoretical design concerning the undergraduate thesis at the Cuban University of Informatics Sciences (UIS. This analysis proves to be decisive due to the existing demand for improving professionals training in the fields of investigation related to computing world.
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Marcus H Heitger
Full Text Available In bimanual coordination, older and younger adults activate a common cerebral network but the elderly also have additional activation in a secondary network of brain areas to master task performance. It remains unclear whether the functional connectivity within these primary and secondary motor networks differs between the old and the young and whether task difficulty modulates connectivity. We applied graph-theoretical network analysis (GTNA to task-driven fMRI data in 16 elderly and 16 young participants using a bimanual coordination task including in-phase and anti-phase flexion/extension wrist movements. Network nodes for the GTNA comprised task-relevant brain areas as defined by fMRI activation foci. The elderly matched the motor performance of the young but showed an increased functional connectivity in both networks across a wide range of connectivity metrics, i.e., higher mean connectivity degree, connection strength, network density and efficiency, together with shorter mean communication path length between the network nodes and also a lower betweenness centrality. More difficult movements showed an increased connectivity in both groups. The network connectivity of both groups had "small world" character. The present findings indicate (a that bimanual coordination in the aging brain is associated with a higher functional connectivity even between areas also activated in young adults, independently from task difficulty, and (b that adequate motor coordination in the context of task-driven bimanual control in older adults may not be solely due to additional neural recruitment but also to aging-related changes of functional relationships between brain regions.
del Rio, B. G.; González, L. E.
2017-06-01
We perform ab initio molecular dynamics simulations of liquid Zn near the melting point in order to study the longitudinal and transverse dynamic properties of the system. We find two propagating excitations in both of them in a wide range of wave vectors. This is in agreement with some experimental observations of the dynamic structure factor in the region around half the position of the main peak. Moreover, the two-mode structure in the transverse and longitudinal current correlation functions had also been previously observed in high pressure liquid metallic systems. We perform a theoretical analysis in order to investigate the possible origin of such two components by resorting to mode-coupling theories. They are found to describe qualitatively the appearance of two modes in the dynamics, but their relative intensities are not quantitatively reproduced. We suggest some possible improvements of the theory through the analysis of the structure of the memory functions. We also analyze the single-particle dynamics embedded in the velocity autocorrelation function, and explain its characteristics through mode-coupling concepts.
A Framework for the Game-theoretic Analysis of Censorship Resistance
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Elahi Tariq
2016-10-01
Full Text Available We present a game-theoretic analysis of optimal solutions for interactions between censors and censorship resistance systems (CRSs by focusing on the data channel used by the CRS to smuggle clients’ data past the censors. This analysis leverages the inherent errors (false positives and negatives made by the censor when trying to classify traffic as either non-circumvention traffic or as CRS traffic, as well as the underlying rate of CRS traffic. We identify Nash equilibrium solutions for several simple censorship scenarios and then extend those findings to more complex scenarios where we find that the deployment of a censorship apparatus does not qualitatively change the equilibrium solutions, but rather only affects the amount of traffic a CRS can support before being blocked. By leveraging these findings, we describe a general framework for exploring and identifying optimal strategies for the censorship circumventor, in order to maximize the amount of CRS traffic not blocked by the censor. We use this framework to analyze several scenarios with multiple data-channel protocols used as cover for the CRS. We show that it is possible to gain insights through this framework even without perfect knowledge of the censor’s (secret values for the parameters in their utility function.
Theoretical Analysis on the Effect of Tunnel Excavation on Building strip foundation
Tian, Xiaoyan; Gu, Shuancheng; Huang, Rongbin
2017-09-01
In this paper, according to the characteristics of the ground settlement troughs curves, the influence of tunnel excavation on the effect of strip foundation was studied by inverse analysis firstly. The differential equation of the synergistic effect of the strip foundation and foundation under the tunnel excavation was established by using the equilibrium condition of the micro-element physical force. Then, the conceptual definite initial parameter method was used to solve the corresponding homogeneous equation. According to the plane section assumption, combined with the basic theory of material mechanics, considering the differential characteristic of hyperbolic trigonometric function, and using matlabmathmatica software, the theoretical calculation expression of displacement and internal force which is about the tunnel passes through the strip foundation was obtained. Finally, combined with engineering case analysis, changes of the relative position between the tunnel and the foundation, the influences of the main parameters on the foundation effect were studied. The results show that: The influence scope of the tunnel on the foundation is [-0.5 ~ 1.5] times of the foundation length, and when the tunnel center at the end of the foundation, there exists the maximum settlement. The parameters about the soil loss rate, the excavation section and the buried depth of the tunnel have great influence on the foundation effect. The change of foundation height has a great influence on its internal force.
CONFLICT ANALYSIS OF CITARUM RIVER BASIN POLLUTION IN INDONESIA: A DRAMA-THEORETIC MODEL
Institute of Scientific and Technical Information of China (English)
Pri HERMAWAN; Kyoichi KIJIMA
2009-01-01
The need to manage water resource within a holistic approach is crucial in Indonesia. Conflict situation which involves a variety of stakeholder needs an appropriate methodology to handle it. The purpose of this paper is to provide an integrated framework of a river basin pollution case in Indonesia. This research try to obtain an understanding of the complexity of inter-relationship between stakeholders of the Citarum River Basin and to give feasible recommendations based on a new developed integrated framework. We first describe the problem in a comprehensive way, then develop a framework to analyze the conflict. Next, we propose a general procedure to apply it, which we call Drama-theoretic Dilemma Analysis (DtDA). After analyzing the conflicts that arise there between stakeholders using DtDA, we will show how to resolve the dilemmas by using holistic as well as intensive approaches. By applying DtDA in stakeholder analysis and resolving the dilemmas that arise in the interactions between them, we can identify barriers for collaboration.
Wettability of graphitic-carbon and silicon surfaces: MD modeling and theoretical analysis
Ramos-Alvarado, Bladimir; Kumar, Satish; Peterson, G. P.
2015-07-01
The wettability of graphitic carbon and silicon surfaces was numerically and theoretically investigated. A multi-response method has been developed for the analysis of conventional molecular dynamics (MD) simulations of droplets wettability. The contact angle and indicators of the quality of the computations are tracked as a function of the data sets analyzed over time. This method of analysis allows accurate calculations of the contact angle obtained from the MD simulations. Analytical models were also developed for the calculation of the work of adhesion using the mean-field theory, accounting for the interfacial entropy changes. A calibration method is proposed to provide better predictions of the respective contact angles under different solid-liquid interaction potentials. Estimations of the binding energy between a water monomer and graphite match those previously reported. In addition, a breakdown in the relationship between the binding energy and the contact angle was observed. The macroscopic contact angles obtained from the MD simulations were found to match those predicted by the mean-field model for graphite under different wettability conditions, as well as the contact angles of Si(100) and Si(111) surfaces. Finally, an assessment of the effect of the Lennard-Jones cutoff radius was conducted to provide guidelines for future comparisons between numerical simulations and analytical models of wettability.
Institute of Scientific and Technical Information of China (English)
Hai-Long Chen; Feng-Nian Jin; Hua-Lin Fan
2013-01-01
Due to the wide applications of arches in underground protective structures,dynamic analysis of circular arches including soil-structure interactions is important.In this paper,an exact solution of the forced vibration of circular arches subjected to subsurface denotation forces is obtained.The dynamic soil-structure interaction is considered with the introduction of an interfacial damping between the structure element and the surrounding soil into the equation of motion.By neglecting the influences of shear,rotary inertia and tangential forces and assuming the arch incompressible,the equations of motion of the buried arches were set up.Analytical solutions of the dynamic responses of the protective arches were deduced by means of modal superposition.Arches with different opening angles,acoustic impedances and rise-span ratios were analyzed to discuss their influences on an arch.The theoretical analysis suggests blast loads for elastic designs and predicts the potential failure modes for buried protective arches.
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Mercedes Querol-Julián
2014-12-01
Full Text Available Discussions sessions have not received much attention within the genre of conference presentations. In this paper, we present the theoretical framework that underlies the approach followed to analyse the multimodal expression of evaluation. Then, an example of the application of the study has been considered necessary to understand it. Corpus linguistics provided the indications to collect the corpus, annotate it and find the appropriate software to digitalise the relevant information for the study. Secondly, genre studies and conversational analysis gave the clues to establish a structure in the linguistic expressions found in the discussion sessions of paper presentations. Thirdly, systemic functional linguistics and pragmatics provided the basis for an evaluative scheme that could be applied to the academic discourse of the corpus, considering its multimodal nature. Fourthly, the tools to observe the non-verbal communication associated with evaluative language were found in multimodal discourse analysis studies. All together, the application of these variables led to an original study of discussion sessions, which deployed interesting results.
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.
Theoretical and Experimental Spectroscopic Analysis of Cyano-Substituted Styrylpyridine Compounds
Jorge Lopez-Cruz; Francisco J. Melendez; Guillermo Soriano-Moro; Chapela, Victor M.; Margarita Ceron; Maria Eugenia Castro; Maria Judith Percino
2013-01-01
A combined theoretical and experimental study on the structure, infrared, UV-Vis and 1H NMR data of trans-2-(m-cyanostyryl)pyridine, trans-2-[3-methyl-(m-cyanostyryl)] pyridine and trans-4-(m-cyanostyryl)pyridine is presented. The synthesis was carried out with an efficient Knoevenagel condensation using green chemistry conditions. Theoretical geometry optimizations and their IR spectra were carried out using the Density Functional Theory (DFT) in both gas and solution phases. For theoretical...
UC Cooperative Extension sensory analysis panel enhances the quality of California olive oil
Paul VOSSEN; Kicenik Devarenne, Alexandra
2011-01-01
California’s olive oil industry has evolved from primarily a salvage operation of the table olive industry to a producer of world-class, premium, extra-virgin olive oil. In 1997, UC Cooperative Extension started the first California olive oil taste panel, which was officially recognized by the International Olive Council in 2001. Specific protocols were used to screen potential panelists and train them to identify defects and positive characteristics, identical to 43 other world taste panels....
Synthesis, measurements, and theoretical analysis of carbazole derivatives with high-triplet-energy
Energy Technology Data Exchange (ETDEWEB)
Li Jianli; Mi Xiaoyun; Wan Yuchun [School of Materials Science and Engineering, Changchun University of Science and Technology, Changchun 130022 (China); Si Zhenjun, E-mail: szj@cust.edu.cn [School of Materials Science and Engineering, Changchun University of Science and Technology, Changchun 130022 (China); Institute of Organic Chemistry and Biochemistry, Czech Academy of Science, Praha 6 16610 (Czech Republic); Sun Haiying; Duan Qian [School of Materials Science and Engineering, Changchun University of Science and Technology, Changchun 130022 (China); He Xingquan [School of Chemistry and Environmental Engineering, Changchun University of Science and Technology, Changchun 130022 (China); Yan Dong; Wan Sha [School of Materials Science and Engineering, Changchun University of Science and Technology, Changchun 130022 (China)
2012-05-15
In order to obtain the blue light-emitting organic materials with high triplet state energy, two 3,5-diphenyl-4H-1,2,4-triazole (Tz) containing carbazole (Cz) derivatives of 9-(4-(3,5-diphenyl-4H-1,2,4-triazol-4-yl)phenyl)-9H-carbazole (TzCz1) and 3,6-di-tert-butyl-9-(4-(3,5-diphenyl-4H-1,2,4-triazol-4-yl)phenyl) -9H-carbazole (TzCz2) are synthesized using Cz acting as the starting material, as well as characterized by the {sup 1}H NMR spectra, ultraviolet-visible (UV-vis) absorption spectra, and the IR absorption spectra. The luminescence quantum yields (LQYs) of TzCz1 and TzCz2 are measured in CH{sub 2}Cl{sub 2} solution to be 32.1% and 47.5%, respectively. The electrochemical analysis and the photophysical measurements suggest that the triplet energy levels and the energy gaps of the highest-occupied orbital and the lowest-unoccupied orbital are 2.83 eV and 3.59 eV for TzCz1, and 2.80 eV and 3.43 eV for TzCz2. At last, the theoretical analyses of their ground state geometries and the simulated UV-vis absorption spectra are carried out at B3LYP1/6-31G Low-Asterisk level. The studies mentioned above indicate that both TzCz1 and TzCz2 are suitable for the host materials of blue light-emitting diodes. - Highlights: Black-Right-Pointing-Pointer Synthesis of two blue light-emitting Carbazole derivatives. Black-Right-Pointing-Pointer Photophysical and electrochemical properties are systematically studied. Black-Right-Pointing-Pointer Theoretical analysis of geometry of the ground states and the UV-vis absorption are performed with Firefly package. Black-Right-Pointing-Pointer The triplet energy levels are measured to be ca. 2.83 eV.
Volkov, Alexey N.; Salaway, Richard N.; Zhigilei, Leonid V.
2013-09-01
The propensity of carbon nanotubes (CNTs) to self-organize into continuous networks of bundles has direct implications for thermal transport properties of CNT network materials and defines the importance of clear understanding of the mechanisms and scaling laws governing the heat transfer within the primary building blocks of the network structures—close-packed bundles of CNTs. A comprehensive study of the thermal conductivity of CNT bundles is performed with a combination of non-equilibrium molecular dynamics (MD) simulations of heat transfer between adjacent CNTs and the intrinsic conductivity of CNTs in a bundle with a theoretical analysis that reveals the connections between the structure and thermal transport properties of CNT bundles. The results of MD simulations of heat transfer in CNT bundles consisting of up to 7 CNTs suggest that, contrary to the widespread notion of strongly reduced conductivity of CNTs in bundles, van der Waals interactions between defect-free well-aligned CNTs in a bundle have negligible effect on the intrinsic conductivity of the CNTs. The simulations of inter-tube heat conduction performed for partially overlapping parallel CNTs indicate that the conductance through the overlap region is proportional to the length of the overlap for CNTs and CNT-CNT overlaps longer than several tens of nm. Based on the predictions of the MD simulations, a mesoscopic-level model is developed and applied for theoretical analysis and numerical modeling of heat transfer in bundles consisting of CNTs with infinitely large and finite intrinsic thermal conductivities. The general scaling laws predicting the quadratic dependence of the bundle conductivity on the length of individual CNTs in the case when the thermal transport is controlled by the inter-tube conductance and the independence of the CNT length in another limiting case when the intrinsic conductivity of CNTs plays the dominant role are derived. An application of the scaling laws to bundles of
Efficiency of village extension agents in Nigeria: Evidence from a data envelopment analysis
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Ibrahim Hassan I.
2016-01-01
Full Text Available Determining the technical efficiency of extension personnel especially at the village level is paramount if farm productivity is to be increased. The present study determined the technical efficiency of Village Extension Agents (VEAs in North Central Nigeria. Data for the study were collected using structured questionnaire that was administered on 81 VEAs. The findings of the study indicated that 32.1% of the VEAs were aged between 38 and 45 years with a mean age of 41 years; while 50.6% were holders of national diploma certificates. The monthly income of a VEA ranged between N16,000 and N21,000. The average technical efficiency of VEAs was 42% with minimum and maximum values of 0.03 and 1 respectively. There was a positive significant association between the age (P<0.10, education (P<0. 10 and income (P<0.01 of VEAs and their technical efficiency levels. The results imply that prompt payment of allowances/salary, regular promotions and trainings are the necessary impetus that can improve agricultural extension service delivery in Nigeria, particularly at the village level.
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Sterling
2015-09-01
Full Text Available Background Evidence suggests that morbid obesity may be an independent risk factor for adverse outcomes in patients with traumatic injuries. Objectives In this study, a theoretic analysis using a derivation of the Guyton model of cardiovascular physiology examines the expected impact of obesity on hemodynamic changes in Mean Arterial Pressure (MAP and Cardiac Output (CO during Hemorrhagic Shock (HS. Patients and Methods Computer simulation studies were used to predict the relative impact of increasing Body Mass Index (BMI on global hemodynamic parameters during HS. The analytic procedure involved recreating physiologic conditions associated with changing BMI for a virtual subject in an In Silico environment. The model was validated for the known effect of a BMI of 30 on iliofemoral venous pressures. Then, the relative effect of changing BMI on the outcome of target cardiovascular parameters was examined during simulated acute loss of blood volume in class II hemorrhage. The percent changes in these parameters were compared between the virtual nonobese and obese subjects. Model parameter values are derived from known population distributions, producing simulation outputs that can be used in a deductive systems analysis assessment rather than traditional frequentist statistical methodologies. Results In hemorrhage simulation, moderate increases in BMI were found to produce greater decreases in MAP and CO compared to the normal subject. During HS, the virtual obese subject had 42% and 44% greater falls in CO and MAP, respectively, compared to the nonobese subject. Systems analysis of the model revealed that an increase in resistance to venous return due to changes in intra-abdominal pressure resulting from obesity was the critical mechanism responsible for the differences. Conclusions This study suggests that obese patients in HS may have a higher risk of hemodynamic instability compared to their nonobese counterparts primarily due to obesity
Sterling, Sarah A.; Jones, Alan E.; Coleman, Thomas G.; Summers, Richard L.
2015-01-01
Background: Evidence suggests that morbid obesity may be an independent risk factor for adverse outcomes in patients with traumatic injuries. Objectives: In this study, a theoretic analysis using a derivation of the Guyton model of cardiovascular physiology examines the expected impact of obesity on hemodynamic changes in Mean Arterial Pressure (MAP) and Cardiac Output (CO) during Hemorrhagic Shock (HS). Patients and Methods: Computer simulation studies were used to predict the relative impact of increasing Body Mass Index (BMI) on global hemodynamic parameters during HS. The analytic procedure involved recreating physiologic conditions associated with changing BMI for a virtual subject in an In Silico environment. The model was validated for the known effect of a BMI of 30 on iliofemoral venous pressures. Then, the relative effect of changing BMI on the outcome of target cardiovascular parameters was examined during simulated acute loss of blood volume in class II hemorrhage. The percent changes in these parameters were compared between the virtual nonobese and obese subjects. Model parameter values are derived from known population distributions, producing simulation outputs that can be used in a deductive systems analysis assessment rather than traditional frequentist statistical methodologies. Results: In hemorrhage simulation, moderate increases in BMI were found to produce greater decreases in MAP and CO compared to the normal subject. During HS, the virtual obese subject had 42% and 44% greater falls in CO and MAP, respectively, compared to the nonobese subject. Systems analysis of the model revealed that an increase in resistance to venous return due to changes in intra-abdominal pressure resulting from obesity was the critical mechanism responsible for the differences. Conclusions: This study suggests that obese patients in HS may have a higher risk of hemodynamic instability compared to their nonobese counterparts primarily due to obesity
Lu, D.; Takizawa, A.; Kondo, S.
A newly developed ``physical component boundary fitted coordinate (PCBFC) method'' is extended for the analysis of free-surface flows coupled with moving boundaries. Extra techniques are employed to deal with the coupling movement of the free surface and moving boundaries. After the validation of the extension by several benchmark problems, the method is successfully applied for the first time to the simulation of overflow-induced vibration of the weir coupled with sloshing of the free-surface liquid.
Theoretical analysis for scaling law of thermal blooming based on optical phase deference
Sun, Yunqiang; Huang, Zhilong; Ren, Zebin; Chen, Zhiqiang; Guo, Longde; Xi, Fengjie
2016-10-01
In order to explore the laser propagation influence of thermal blooming effect of pipe flow and to analysis the influencing factors, scaling law theoretical analysis of the thermal blooming effects in pipe flow are carry out in detail based on the optical path difference caused by thermal blooming effects in pipe flow. Firstly, by solving the energy coupling equation of laser beam propagation, the temperature of the flow is obtained, and then the optical path difference caused by the thermal blooming is deduced. Through the analysis of the influence of pipe size, flow field and laser parameters on the optical path difference, energy scaling parameters Ne=nTαLPR2/(ρɛCpπR02) and geometric scaling parameters Nc=νR2/(ɛL) of thermal blooming for the pipe flow are derived. Secondly, for the direct solution method, the energy coupled equations have analytic solutions only for the straight tube with Gauss beam. Considering the limitation of directly solving the coupled equations, the dimensionless analysis method is adopted, the analysis is also based on the change of optical path difference, same scaling parameters for the pipe flow thermal blooming are derived, which makes energy scaling parameters Ne and geometric scaling parameters Nc have good universality. The research results indicate that when the laser power and the laser beam diameter are changed, thermal blooming effects of the pipeline axial flow caused by optical path difference will not change, as long as you keep energy scaling parameters constant. When diameter or length of the pipe changes, just keep the geometric scaling parameters constant, the pipeline axial flow gas thermal blooming effects caused by optical path difference distribution will not change. That is to say, when the pipe size and laser parameters change, if keeping two scaling parameters with constant, the pipeline axial flow thermal blooming effects caused by the optical path difference will not change. Therefore, the energy scaling
Traynor, Michael
2006-04-01
The aim of the paper is (1) to offer an overview of different theoretical approaches to discourse analysis and (2) to review papers published in the Journal of Advanced Nursing from 1996-2004 in which discourse analysis is identified as a method of data analysis. Discourse analysis offers rigorous approaches to analysing naturally occurring talk and texts. Forms of discourse analysis have developed across broad theoretical bases. Such development has created challenges for researchers wishing to adopt this methodology and readers wishing to evaluate the quality of discourse analytic work. First, key documents which describe the theoretical range of discourse analysis are used to provide (i) a comprehensive overview of the approach, (ii) the identification of categories of discourse analysis and (iii) minimum criteria for determining if an individual paper can realistically claim to be adopting discourse analysis. Secondly, an electronic search followed by hand search of the Journal of Advanced Nursing full-contents between 1996 and 2004 was undertaken. The papers were grouped into the types of approach identified in i, and evaluated to see whether they met the 'minimum criteria' also identified in i. The search of Journal of Advanced Nursing revealed 24 papers where the authors stated that discourse analysis was among the methods or was the sole method of data analysis. The majority of the papers cluster around critical approaches to discourse analysis. Only a few approach discourse analysis primarily as analysis of conversation. Some papers are excellent, while others offer analysis that bears little resemblance to any form of discourse analysis. A strategy for improvement could include more rigorous attention on the part of those practising discourse analysis to methodology and the key features that differentiate the different approaches to discourse analysis from other qualitative methods. Authors should include sufficient detail of their approach.
Theoretical Analysis of Heat Stress Prefabricating the Crack in Precision Cropping
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Lijun Zhang
2013-07-01
Full Text Available The mathematical model of the metal bar in course of heat treatment is built by regarding the convective heat transfer process of the metal bar as the heat conduction boundary condition. By the theory analysis and numerical simulation methods, the theoretical expression of unsteady multidimensional temperature field for the axisymmetric model of metal bar is obtained. Temperature field distribution of bar V-shaped notch equivalent tip is given by ANSYS software. The quantitative relationship between temperature of bar inner key points and the time is determined. Through the polynomial curve fitting, the relation between the ultimate strength and the temperature is also given. Based on it, the influences of the width of the adiabatic boundary and water velocity on the critical temperature gradient of germinating heat crack in the tip of V-shaped notch are analyzed. The experimental results in precision cropping show that the expression of unsteady multidimensional temperature field is feasible in the rapid calculation of crack generation.
Theoretical Performance Analysis of Indirect-Direct Evaporative Cooler in Hot and Dry Climates
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R.K.KULKARNI,
2011-02-01
Full Text Available This paper theoretically analyses the performance of indirect-direct two stage cooler in hot and dry climate of Bhopal, India. Indirect cooling stage consisting of plate type wet surface heat exchangerfollowed by direct cooling stage consisting of rigid cellulose and aspen fiber in rectangular, semicylindrical and semi-hexagonal shapes as cooling media is considered. Based on summer weather data ofBhopal, most frequently occurring condition of 39.9 0C DBT and 32.8 % RH is selected for the analysis. Indirect evaporative cooler effectiveness is estimated in the range of 0.95 to 0.82 for primary air flow rate of 0.3 to 1.25 kg/s. Saturation efficiency in the direct cooling mode is obtained in the range of 89.1 to 63.4 % and cooling capacity from 11472 to 52576 kJ/h for different combinations. In combined mode saturation efficiency is obtained between 121.5 and 106.7 % and cooling capacity between 18244 to 73809 kJ/h. The final outlet temperature of air in combined mode ranges between 22.5 0C and 24.6 0C.
Smith, Robert; Fuss, Franz Konstantin
2013-09-06
This paper is a theoretical analysis of mirror tilt in a Michelson interferometer and its effect on the radiant flux over the active area of a rectangular photodetector or image sensor pixel. It is relevant to sensor applications using homodyne interferometry where these opto-electronic devices are employed for partial fringe counting. Formulas are derived for radiant flux across the detector for variable location within the fringe pattern and with varying wave front angle. The results indicate that the flux is a damped sine function of the wave front angle, with a decay constant of the ratio of wavelength to detector width. The modulation amplitude of the dynamic fringe pattern reduces to zero at wave front angles that are an integer multiple of this ratio and the results show that the polarity of the radiant flux changes exclusively at these multiples. Varying tilt angle causes radiant flux oscillations under an envelope curve, the frequency of which is dependent on the location of the detector with the fringe pattern. It is also shown that a fringe count of zero can be obtained for specific photodetector locations and wave front angles where the combined effect of fringe contraction and fringe tilt can have equal and opposite effects. Fringe tilt as a result of a wave front angle of 0.05° can introduce a phase measurement difference of 16° between a photodetector/pixel located 20 mm and one located 100 mm from the optical origin.
Directory of Open Access Journals (Sweden)
Franz Konstantin Fuss
2013-09-01
Full Text Available This paper is a theoretical analysis of mirror tilt in a Michelson interferometer and its effect on the radiant flux over the active area of a rectangular photodetector or image sensor pixel. It is relevant to sensor applications using homodyne interferometry where these opto-electronic devices are employed for partial fringe counting. Formulas are derived for radiant flux across the detector for variable location within the fringe pattern and with varying wave front angle. The results indicate that the flux is a damped sine function of the wave front angle, with a decay constant of the ratio of wavelength to detector width. The modulation amplitude of the dynamic fringe pattern reduces to zero at wave front angles that are an integer multiple of this ratio and the results show that the polarity of the radiant flux changes exclusively at these multiples. Varying tilt angle causes radiant flux oscillations under an envelope curve, the frequency of which is dependent on the location of the detector with the fringe pattern. It is also shown that a fringe count of zero can be obtained for specific photodetector locations and wave front angles where the combined effect of fringe contraction and fringe tilt can have equal and opposite effects. Fringe tilt as a result of a wave front angle of 0.05° can introduce a phase measurement difference of 16° between a photodetector/pixel located 20 mm and one located 100 mm from the optical origin.
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Matthias Dehmer
Full Text Available This paper aims to investigate information-theoretic network complexity measures which have already been intensely used in mathematical- and medicinal chemistry including drug design. Numerous such measures have been developed so far but many of them lack a meaningful interpretation, e.g., we want to examine which kind of structural information they detect. Therefore, our main contribution is to shed light on the relatedness between some selected information measures for graphs by performing a large scale analysis using chemical networks. Starting from several sets containing real and synthetic chemical structures represented by graphs, we study the relatedness between a classical (partition-based complexity measure called the topological information content of a graph and some others inferred by a different paradigm leading to partition-independent measures. Moreover, we evaluate the uniqueness of network complexity measures numerically. Generally, a high uniqueness is an important and desirable property when designing novel topological descriptors having the potential to be applied to large chemical databases.
Intrinsic functional brain architecture derived from graph theoretical analysis in the human fetus.
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Moriah E Thomason
Full Text Available The human brain undergoes dramatic maturational changes during late stages of fetal and early postnatal life. The importance of this period to the establishment of healthy neural connectivity is apparent in the high incidence of neural injury in preterm infants, in whom untimely exposure to ex-uterine factors interrupts neural connectivity. Though the relevance of this period to human neuroscience is apparent, little is known about functional neural networks in human fetal life. Here, we apply graph theoretical analysis to examine human fetal brain connectivity. Utilizing resting state functional magnetic resonance imaging (fMRI data from 33 healthy human fetuses, 19 to 39 weeks gestational age (GA, our analyses reveal that the human fetal brain has modular organization and modules overlap functional systems observed postnatally. Age-related differences between younger (GA <31 weeks and older (GA≥31 weeks fetuses demonstrate that brain modularity decreases, and connectivity of the posterior cingulate to other brain networks becomes more negative, with advancing GA. By mimicking functional principles observed postnatally, these results support early emerging capacity for information processing in the human fetal brain. Current technical limitations, as well as the potential for fetal fMRI to one day produce major discoveries about fetal origins or antecedents of neural injury or disease are discussed.
Schenk, Jamie; Mao, James X; Smuts, Jonathan; Walsh, Phillip; Kroll, Peter; Schug, Kevin A
2016-11-16
An issue with most gas chromatographic detectors is their inability to deconvolve coeluting isomers. Dimethylnaphthalenes are a class of compounds that can be particularly difficult to speciate by gas chromatography - mass spectrometry analysis, because of their significant coelution and similar mass spectra. As an alternative, a vacuum ultraviolet spectroscopic detector paired with gas chromatography was used to study the systematic deconvolution of mixtures of coeluting isomers of dimethylnaphthalenes. Various ratio combinations of 75:25; 50:50; 25:75; 20:80; 10:90; 5:95; and 1:99 were prepared to test the accuracy, precision, and sensitivity of the detector for distinguishing overlapping isomers that had distinct, but very similar absorption spectra. It was found that, under reasonable injection conditions, all of the pairwise overlapping isomers tested could be deconvoluted up to nearly two orders of magnitude (up to 99:1) in relative abundance. These experimental deconvolution values were in agreement with theoretical covariance calculations performed for two of the dimethylnaphthalene isomers. Covariance calculations estimated high picogram detection limits for a minor isomer coeluting with low to mid-nanogram quantity of a more abundant isomer. Further characterization of the analytes was performed using density functional theory computations to compare theory with experimental measurements. Additionally, gas chromatography - vacuum ultraviolet spectroscopy was shown to be able to speciate dimethylnaphthalenes in jet and diesel fuel samples. Copyright © 2016 Elsevier B.V. All rights reserved.
Experimental and theoretical analysis of the actuation behavior of magnetoactive elastomers
Maas, Jürgen; Uhlenbusch, Dominik
2016-10-01
Composites made of an elastomeric matrix and a magnetizable filler, called magnetoactive elastomers (MAEs), are able to undergo a change of their rheological or damping behavior by applying external magnetic fields. Furthermore, these fields lead to actuation forces and deformations of these materials. Consequential, actuation forces and deformations caused by this behavior can be utilized in an actuation mode of the MAE material. To investigate the induced actuation characteristic different cylindrical MAE specimens are described in a first step. In order to perform a measurement of the actuation a suitable test bench is specified and designed. By this test bench a variable external magnetic field has to be provided within an airgap the MAE specimen are placed in. Furthermore, it has to enable a measurement of the induced actuation forces in a specified axial direction on the one hand and the induced elongation in the same direction on the other hand. Subsequently, a theoretical investigation of the described behavior is performed by use of a suitable finite element analysis (FEA). Therefore, an appropriate continuum mechanical modeling approach based on the Kelvin force is introduced. Implementation of this modeling approach within the FEA-tool Comsol Multiphysics enables a coupled simulation of the magnetism and structural-mechanics domain. Finally, an experimental validation of the modeling approach is carried out by measurements using the developed test bench showing a good accordance.
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Maksymchuk Borys
2016-12-01
Full Text Available The article deals with the analysis of theoretical and methodical principles of forming students’ valeological competency in the process of physical education in higher pedagogical education institutions in domestic and foreign scientific literature. It has been defined that one of the most prominent factors in future teachers’ training for valeological education is higher pedagogical education. The content and character of its influence determine the way how future teachers are trained to organize valeological education at schools, teach the Basics of Health to the 1-4 graders, adhere to the most important principles of the educational process that ensure a gradual and effective solving of valeological tasks. It has been concluded that the competency-based approach ensures social realization of specialists as it teaches how to solve professional needs and problems that emerge in cognitive, technological and mental activities, in the spheres of ethical, social, legal, professional, personal relations, provides for such educational content that does not contain only a knowledgeoriented component, but also provides integrative experience in solving life problems, carrying out key functions, social roles, realizing competences.
A Detection-Theoretic Analysis of Auditory Streaming and Its Relation to Auditory Masking
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An-Chieh Chang
2016-09-01
Full Text Available Research on hearing has long been challenged with understanding our exceptional ability to hear out individual sounds in a mixture (the so-called cocktail party problem. Two general approaches to the problem have been taken using sequences of tones as stimuli. The first has focused on our tendency to hear sequences, sufficiently separated in frequency, split into separate cohesive streams (auditory streaming. The second has focused on our ability to detect a change in one sequence, ignoring all others (auditory masking. The two phenomena are clearly related, but that relation has never been evaluated analytically. This article offers a detection-theoretic analysis of the relation between multitone streaming and masking that underscores the expected similarities and differences between these phenomena and the predicted outcome of experiments in each case. The key to establishing this relation is the function linking performance to the information divergence of the tone sequences, DKL (a measure of the statistical separation of their parameters. A strong prediction is that streaming and masking of tones will be a common function of DKL provided that the statistical properties of sequences are symmetric. Results of experiments are reported supporting this prediction.
ACTIVE DISTURBANCE REJECTION CONTROL: METHODOLOGY AND THEORETICAL ANALYSIS%自抗扰控制纵横谈
Institute of Scientific and Technical Information of China (English)
黄一; 薛文超; 赵春哲
2011-01-01
The paper first gives a comprehensive comparison of the frame of the Active Disturbance Rejection Control (AQDRC) with other methods for controlling uncertain systems, which includes the adaptive control, robust control, disturbance observers based methods, etc. Then the process of theoretical analysis for ADRC, mainly concluding the convergence of the tracking differentiator (TD), the capabilities of the extended state observer (ESO) for estimating uncertainties and the performance of the ADRC based closed-loop system is reviewed. Finally, ADRC's contributions to the research of controlling uncertain systems are concluded.%首先从不确定系统控制的角度,将自抗扰控制与其它一些有关不确定系统控制的理论与方法进行比较和讨论,然后围绕自抗扰控制理论分析方面的进展,以及需要进一步研究的课题进行深入讨论与总结.通过纵横两方面的讨论揭示自抗扰控制对推进不确定系统控制研究的贡献,以及自抗扰控制方法的突出特点.
Characteristics of a micro-fin evaporator: Theoretical analysis and experimental verification
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Zheng Hui-Fan
2013-01-01
Full Text Available A theoretical analysis and experimental verification on the characteristics of a micro-fin evaporator using R290 and R717 as refrigerants were carried out. The heat capacity and heat transfer coefficient of the micro-fin evaporator were investigated under different water mass flow rate, different refrigerant mass flow rate, and different inner tube diameter of micro-fin evaporator. The simulation results of the heat transfer coefficient are fairly in good agreement with the experimental data. The results show that heat capacity and the heat transfer coefficient of the micro-fin evaporator increase with increasing logarithmic mean temperature difference, the water mass flow rate and the refrigerant mass flow rate. Heat capacity of the micro-fin evaporator for diameter 9.52 mm is higher than that of diameter 7.00 mm with using R290 as refrigerant. Heat capacity of the micro-fin evaporator with using R717 as refrigerant is higher than that of R290 as refrigerant. The results of this study can provide useful guidelines for optimal design and operation of micro-fin evaporator in its present or future applications.
A theoretical analysis of river bars stability under changing channel width
Zen, S.; Zolezzi, G.; Tubino, M.
2014-04-01
In this paper we propose a new theoretical model to investigate the influence of temporal changes in channel width on river bar stability. This is achieved by performing a nonlinear stability analysis, which includes temporal width variations as a small-amplitude perturbation of the basic flow. In order to quantify width variability, channel width is related with the instantaneous discharge using existing empirical formulae proposed for channels with cohesionless banks. Therefore, width can vary (increase and/or decrease) either because it adapts to the temporally varying discharge or, if discharge is constant, through a relaxation relation describing widening of an initially overnarrow channel towards the equilibrium width. Unsteadiness related with changes in channel width is found to directly affect the instantaneous bar growth rate, depending on the conditions under which the widening process occurs. The governing mathematical system is solved by means of a two-parameters (ɛ, δ) perturbation expansion, where ɛ is related to bar amplitude and δ to the temporal width variability. In general width unsteadiness is predicted to play a destabilizing role on free bar stability, namely during the peak stage of a flood event in a laterally unconfined channel and invariably for overnarrow channels fed with steady discharge. In this latter case, width unsteadiness tends to shorten the most unstable bar wavelength compared to the case with constant width, in qualitative agreement with existing experimental observations.
Intrinsic functional brain architecture derived from graph theoretical analysis in the human fetus.
Thomason, Moriah E; Brown, Jesse A; Dassanayake, Maya T; Shastri, Rupal; Marusak, Hilary A; Hernandez-Andrade, Edgar; Yeo, Lami; Mody, Swati; Berman, Susan; Hassan, Sonia S; Romero, Roberto
2014-01-01
The human brain undergoes dramatic maturational changes during late stages of fetal and early postnatal life. The importance of this period to the establishment of healthy neural connectivity is apparent in the high incidence of neural injury in preterm infants, in whom untimely exposure to ex-uterine factors interrupts neural connectivity. Though the relevance of this period to human neuroscience is apparent, little is known about functional neural networks in human fetal life. Here, we apply graph theoretical analysis to examine human fetal brain connectivity. Utilizing resting state functional magnetic resonance imaging (fMRI) data from 33 healthy human fetuses, 19 to 39 weeks gestational age (GA), our analyses reveal that the human fetal brain has modular organization and modules overlap functional systems observed postnatally. Age-related differences between younger (GA brain modularity decreases, and connectivity of the posterior cingulate to other brain networks becomes more negative, with advancing GA. By mimicking functional principles observed postnatally, these results support early emerging capacity for information processing in the human fetal brain. Current technical limitations, as well as the potential for fetal fMRI to one day produce major discoveries about fetal origins or antecedents of neural injury or disease are discussed.
Gui-Li, Zheng; Hui, Zhang; Wen-Jiang, Ye; Zhi-Dong, Zhang; Hong-Wei, Song; Li, Xuan
2016-03-01
Based on the experimental phenomena of flexoelectric response at defect sites in nematic inversion walls conducted by Kumar et al., we gave the theoretical analysis using the Frank elastic theory. When a direct-current electric field normal to the plane of the substrate is applied to the parallel aligned nematic liquid crystal cell with weak anchoring, the rotation of ±1 defects in the narrow inversion walls can be exhibited. The free energy of liquid crystal molecules around the +1 and -1 defect sites in the nematic inversion walls under the electric field was formulated and the electric-field-driven structural changes at the defect site characterized by polar and azimuthal angles of the local director were simulated. The results reveal that the deviation of azimuthal angle induced by flexoelectric effect are consistent with the switching of extinction brushes at the +1 and -1 defects obtained in the experiment conducted by Kumar et al. Project supported by the National Natural Science Foundation of China (Grant Nos. 11374087, 11274088, and 11304074), the Natural Science Foundation of Hebei Province, China (Grant Nos. A2014202123 and A2016202282), the Research Project of Hebei Education Department, China (Grant Nos. QN2014130 and QN2015260), and the Key Subject Construction Project of Hebei Province University, China.
Ge, Hao; Qian, Min
2009-09-01
Cooperativity is one of the "paradigms" in enzyme kinetics and molecular biology. But the classical textbook treatment of enzyme kinetics always indeed separates the concepts of positive/negative cooperativity from enzyme activation/inhibition, at least partially. Few theoretical analysis of their relationship has been discussed, although its experimental investigations might date back at least to 1970s. In the present paper, we try to apply the change of free energy as a connective parameter for investigating the relationship between positive/negative cooperativity and enzyme activation/inhibition through several classic equilibrium binding models. It is explicitly shown that the terms of positive/negative cooperativity could be equivalently regarded as enzyme activation/inhibition of the saturation function induced by the substrate molecule itself rather than any other additional effectors. Moreover, both the degree of cooperativity phenomenon and the degree of enzyme activation/inhibition monotonically increase with the change of free energy. Note that this result is quite different from the idea of relating cooperativity to the concepts of "substrate activation/inhibition", which is identified when at high substrate concentrations the reaction rate decreases instead of tending towards the maximum velocity, since it always needs a second substrate molecule.
A Detection-Theoretic Analysis of Auditory Streaming and Its Relation to Auditory Masking.
Chang, An-Chieh; Lutfi, Robert; Lee, Jungmee; Heo, Inseok
2016-09-18
Research on hearing has long been challenged with understanding our exceptional ability to hear out individual sounds in a mixture (the so-called cocktail party problem). Two general approaches to the problem have been taken using sequences of tones as stimuli. The first has focused on our tendency to hear sequences, sufficiently separated in frequency, split into separate cohesive streams (auditory streaming). The second has focused on our ability to detect a change in one sequence, ignoring all others (auditory masking). The two phenomena are clearly related, but that relation has never been evaluated analytically. This article offers a detection-theoretic analysis of the relation between multitone streaming and masking that underscores the expected similarities and differences between these phenomena and the predicted outcome of experiments in each case. The key to establishing this relation is the function linking performance to the information divergence of the tone sequences, DKL (a measure of the statistical separation of their parameters). A strong prediction is that streaming and masking of tones will be a common function of DKL provided that the statistical properties of sequences are symmetric. Results of experiments are reported supporting this prediction.
Theoretical Physics 1. Theoretical Mechanics
Energy Technology Data Exchange (ETDEWEB)
Dreizler, Reiner M.; Luedde, Cora S. [Frankfurt Univ. (Germany). Inst. fuer Theoretische Physik
2010-07-01
After an introduction to basic concepts of mechanics more advanced topics build the major part of this book. Interspersed is a discussion of selected problems of motion. This is followed by a concise treatment of the Lagrangian and the Hamiltonian formulation of mechanics, as well as a brief excursion on chaotic motion. The last chapter deals with applications of the Lagrangian formulation to specific systems (coupled oscillators, rotating coordinate systems, rigid bodies). The level of this textbook is advanced undergraduate. The authors combine teaching experience of more than 40 years in all fields of Theoretical Physics and related mathematical disciplines and thorough knowledge in creating advanced eLearning content. The text is accompanied by an extensive collection of online material, in which the possibilities of the electronic medium are fully exploited, e.g. in the form of applets, 2D- and 3D-animations. (orig.)
Schache, Anthony G; Baker, Richard; Lamoreux, Larry W
2006-08-01
Minimising measurement variability associated with hip axial rotation and avoiding knee joint angle cross-talk are two fundamental objectives of any method used to define the knee joint flexion-extension axis for purposes of quantitative gait analysis. The aim of this experiment was to compare three different methods of defining this axis: the knee alignment device (KAD) method, a method based on the transepicondylar axis (TEA) and an alternative numerical method (Dynamic). The former two methods are common approaches that have been applied clinically in many quantitative gait analysis laboratories; the latter is an optimisation procedure. A cohort of 20 subjects performed three different functional tasks (normal gait; squat; non-weight bearing knee flexion) on repeated occasions. Three-dimensional hip and knee angles were computed using the three alternative methods of defining the knee joint flexion-extension axis. The repeatability of hip axial rotation measurements during normal gait was found to be significantly better for the Dynamic method (pknee varus-valgus kinematic profile and the degree of knee joint angle cross-talk were smallest for the Dynamic method across all functional tasks. The Dynamic method therefore provided superior results in comparison to the KAD and TEA-based methods and thus represents an attractive solution for orientating the knee joint flexion-extension axis for purposes of quantitative gait analysis.
ANALYSIS OF ISOKINETIC KNEE EXTENSION / FLEXION IN MALE ELITE ADOLESCENT WRESTLERS
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Sanli Sadi Kurdak
2005-12-01
Full Text Available Wrestling requires strength of the upper and lower body musculature which is critical for the athletic performance. Evaluation of the adolescent's skeletal muscle is important to understand body movement, especially including those involved in sports. Strength, power and endurance capacity are defined as parameters of skeletal muscle biomechanical properties. The isokinetic dynamometer is an important toll for making this type of evaluation. However, load range phase of range of motion has to be considered to interpret the data correctly. With this in mind we aimed to investigate the lover body musculature contractile characteristics of adolescent wrestlers together with detailed analyses of load range phase of motion. Thirteen boys aged 12 - 14 years participated to this study. Concentric load range torque, work and power of knee extension and flexion were measured by a Cybex Norm dynamometer at angular velocities from 450°/sec to 30°/sec with 30°/sec decrements for each set. None of the wrestlers were able to attain load range for angular velocities above 390°/sec and 420°/sec for extension and flexion respectively. Detailed analyses of the load range resulted in statistically significant differences in the normalized load range peak torque for extension at 270°/sec (1.44 ± 0.28 Nm·kg-1 and 1.14 ± 0.28 Nm·kg-1 for total and load range peak torque respectively, p < 0.05, and for flexion at 300°/sec (1.26 ± 0.28 Nm·kg-1 and 1.03 ± 0.23 Nm·kg-1 for total and load range peak torque respectively, p < 0.05, compared to total peak torque data. Similarly, the significant difference was found for the work values at 90°/sec (1.91 ± 0.23 Nm·kg-1 and 1.59 ± 0.24 Nm·kg-1 for total and load range work respectively for extension and 1.73 ± 0.21 Nm·kg-1 and 1.49 ± 0.19 Nm·kg-1 for total and load range work respectively for flexion, p < 0.05, and was evident at higher angular velocities (p < 0.001 for both extension and flexion. At
Ri, Shien; Muramatsu, Takashi
2012-06-01
Recently, a rapid and accurate single-shot phase measurement technique called the sampling moiré method has been developed for small-displacement distribution measurements. In this study, the theoretical phase error of the sampling moiré method caused by linear intensity interpolation in the case of a mismatch between the sampling pitch and the original grating pitch is analyzed. The periodic phase error is proportional to the square of the spatial angular frequency of the moiré fringe. Moreover, an effective phase compensation methodology is developed to reduce the periodic phase error. Single-shot phase analysis can perform accurately even when the sampling pitch is not matched to the original grating pitch exactly. The primary simulation results demonstrate the effectiveness of the proposed phase compensation methodology.
Set-theoretic methods in control
Blanchini, Franco
2015-01-01
The second edition of this monograph describes the set-theoretic approach for the control and analysis of dynamic systems, both from a theoretical and practical standpoint. This approach is linked to fundamental control problems, such as Lyapunov stability analysis and stabilization, optimal control, control under constraints, persistent disturbance rejection, and uncertain systems analysis and synthesis. Completely self-contained, this book provides a solid foundation of mathematical techniques and applications, extensive references to the relevant literature, and numerous avenues for further theoretical study. All the material from the first edition has been updated to reflect the most recent developments in the field, and a new chapter on switching systems has been added. Each chapter contains examples, case studies, and exercises to allow for a better understanding of theoretical concepts by practical application. The mathematical language is kept to the minimum level necessary for the adequate for...
Electromyographic Analysis of the Hip Extension Pattern in Visually Impaired Athletes.
Halski, Tomasz; Żmijewski, Piotr; Cięszczyk, Paweł; Nowak, Barbara; Ptaszkowski, Kuba; Slupska, Lucyna; Dymarek, Robert; Taradaj, Jakub
2015-11-22
The objective of the study was to determine the order of muscle recruitment during the active hip joint extension in particular positions in young visually impaired athletes. The average recruitment time (ART) of the gluteus maximus (GM) and the hamstring muscle group (HMG) was assessed by the means of surface electromyography (sEMG). The sequence of muscle recruitment in the female and male group was also taken into consideration. This study followed a prospective, cross - sectional, randomised design, where 76 visually impaired athletes between the age of 18-25 years were enrolled into the research and selected on chosen inclusion and exclusion criteria. Finally, 64 young subjects (32 men and 32 women) were included in the study (age: 21.1 ± 1.05 years; body mass: 68.4 ± 12.4 kg; body height: 1.74 ± 0.09 m; BMI: 22.20 ± 2.25 kg/m2). All subjects were analysed for the ART of the GM and HMG during the active hip extension performed in two different positions, as well as resting and functional sEMG activity of each muscle. Between gender differences were comprised and the correlations between the ART of the GM and HMG with their functional sEMG activity during hip extension in both positions were shown. No significant differences between the ART of the GM and HMG were found (p>0.05). Furthermore, there was no significant difference of ART among both tested positions, as well in male as female subjects (p>0.05).
Electromyographic Analysis of the Hip Extension Pattern in Visually Impaired Athletes
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Halski Tomasz
2015-12-01
Full Text Available The objective of the study was to determine the order of muscle recruitment during the active hip joint extension in particular positions in young visually impaired athletes. The average recruitment time (ART of the gluteus maximus (GM and the hamstring muscle group (HMG was assessed by the means of surface electromyography (sEMG. The sequence of muscle recruitment in the female and male group was also taken into consideration. This study followed a prospective, cross – sectional, randomised design, where 76 visually impaired athletes between the age of 18–25 years were enrolled into the research and selected on chosen inclusion and exclusion criteria. Finally, 64 young subjects (32 men and 32 women were included in the study (age: 21.1 ± 1.05 years; body mass: 68.4 ± 12.4 kg; body height: 1.74 ± 0.09 m; BMI: 22.20 ± 2.25 kg/m2. All subjects were analysed for the ART of the GM and HMG during the active hip extension performed in two different positions, as well as resting and functional sEMG activity of each muscle. Between gender differences were comprised and the correlations between the ART of the GM and HMG with their functional sEMG activity during hip extension in both positions were shown. No significant differences between the ART of the GM and HMG were found (p>0.05. Furthermore, there was no significant difference of ART among both tested positions, as well in male as female subjects (p>0.05.
Stochastic Unit Commitment via Progressive Hedging - Extensive Analysis of Solution Methods
DEFF Research Database (Denmark)
Ordoudis, Christos; Pinson, Pierre; Zugno, Marco
2015-01-01
high computational power, as stochastic models are dramatically more complex than their deterministic counterparts. This paper provides new insight into the potential of Progressive Hedging to decrease the solution time of the stochastic unit commitment problem with a relatively small trade......-off in terms of the suboptimality of the solution. Computational studies show that the run-time is at most half of what is needed to solve the original extensive formulation of the problem, when more than ten wind power scenarios are utilized. These studies demonstrate great potential for solving real...
Analysis of the extensive air showers of ultra-high energy
Energy Technology Data Exchange (ETDEWEB)
Mikhailov, Aleksei A. [Yu.G. Shafer Institute of Cosmophysical Research and Aeronomy, 31 Lenin Ave., 677980 Yakutsk (Russian Federation)
2011-03-15
When we study extensive air showers (EAS), which correlate with pulsars, we had been found showers without a muon component. Here we analyzed the arrival directions of EAS with poor and without a muon component. We find that the arrival directions of these showers correlate with some pulsars which are distributed more isotropy. Among these pulsars with the short period of rotation around their axis are prevailed than it is expected by the catalogue of pulsars. In this connection the data of world arrays are considered.
Analysis of 3D and multiview extensions of the emerging HEVC standard
Vetro, Anthony; Tian, Dong
2012-10-01
Standardization of a new set of 3D formats has been initiated with the goal of improving the coding of stereo and multiview video, and also facilitating the generation of multiview output needed for auto-stereoscopic displays. Part of this effort will develop 3D and multiview extensions of the emerging standard for High Efficiency Video Coding (HEVC). This paper outlines some of the key technologies and architectures being considered for standardization, and analyzes the viability, benefits and drawbacks of different codec designs.
An analysis of a minimal vectorlike extension of the Standard Model
Beylin, V; Kuksa, V; Volchanskiy, N
2016-01-01
We analyze an extension of the Standard Model with an additional SU(2) hypercolor gauge group keeping the Higgs boson as a fundamental field. Vectorlike interactions of new hyperquarks with the intermediate vector bosons are explicitly constructed. We also consider pseudo-Nambu--Goldstone bosons caused by the symmetry breaking SU(4)-> Sp(4). A specific global symmetry of the model with zero hypercharge of the hyperquark doublets ensures the stability of a neutral pseudoscalar field. Some possible manifestations of the lightest states at colliders are also examined.
Pennig, Sibylle; Schady, Arthur
2014-01-01
In some regions the exposure to railway noise is extremely concentrated, which may lead to high residential annoyance. Nonacoustical factors contribute to these reactions, but there is limited evidence on the interrelations between the nonacoustical factors that influence railway noise annoyance. The aims of the present study were (1) to examine exposure-response relationships between long-term railway noise exposure and annoyance in a region severely affected by railway noise and (2) to determine a priori proposed interrelations between nonacoustical factors by structural equation analysis. Residents (n = 320) living close to railway tracks in the Middle Rhine Valley completed a socio-acoustic survey. Individual noise exposure levels were calculated by an acoustical simulation model for this area. The derived exposure-response relationships indicated considerably higher annoyance at the same noise exposure level than would have been predicted by the European Union standard curve, particularly for the night-time period. In the structural equation analysis, 72% of the variance in noise annoyance was explained by the noise exposure (L(den)) and nonacoustical variables. The model provides insights into several causal mechanisms underlying the formation of railway noise annoyance considering indirect and reciprocal effects. The concern about harmful effects of railway noise and railway traffic, the perceived control and coping capacity, and the individual noise sensitivity were the most important factors that influence noise annoyance. All effects of the nonacoustical factors on annoyance were mediated by the perceived control and coping capacity and additionally proposed indirect effects of the theoretical model were supported by the data.
Directory of Open Access Journals (Sweden)
Sibylle Pennig
2014-01-01
Full Text Available In some regions the exposure to railway noise is extremely concentrated, which may lead to high residential annoyance. Nonacoustical factors contribute to these reactions, but there is limited evidence on the interrelations between the nonacoustical factors that influence railway noise annoyance. The aims of the present study were (1 to examine exposure-response relationships between long-term railway noise exposure and annoyance in a region severely affected by railway noise and (2 to determine a priori proposed interrelations between nonacoustical factors by structural equation analysis. Residents (n = 320 living close to railway tracks in the Middle Rhine Valley completed a socio-acoustic survey. Individual noise exposure levels were calculated by an acoustical simulation model for this area. The derived exposure-response relationships indicated considerably higher annoyance at the same noise exposure level than would have been predicted by the European Union standard curve, particularly for the night-time period. In the structural equation analysis, 72% of the variance in noise annoyance was explained by the noise exposure (Lden and nonacoustical variables. The model provides insights into several causal mechanisms underlying the formation of railway noise annoyance considering indirect and reciprocal effects. The concern about harmful effects of railway noise and railway traffic, the perceived control and coping capacity, and the individual noise sensitivity were the most important factors that influence noise annoyance. All effects of the nonacoustical factors on annoyance were mediated by the perceived control and coping capacity and additionally proposed indirect effects of the theoretical model were supported by the data.
Roca, Maite; Oliva, Mónica; Castillo, Raquel; Moliner, Vicente; Tuñón, Iñaki
2010-10-04
A theoretical study of the protein dynamic effects on the hydride transfer between the formate anion and nicotinamide adenine dinucleotide (NAD(+)), catalyzed by formate dehydrogenase (FDH), is presented in this paper. The analysis of free downhill molecular dynamic trajectories, performed in the enzyme and compared with the reaction in aqueous solution, has allowed the study of the dynamic coupling between the reacting fragments and the protein or the solvent water molecules, as well as an estimation of the dynamic effect contribution to the catalytic effect from calculation of the transmission coefficient in the enzyme and in solution. The obtained transmission coefficients for the enzyme and in solution were 0.46±0.04 and 0.20±0.03, respectively. These values represent a contribution to catalysis of 0.5 kcal mol(-1), which, although small, is not negligible keeping in mind the low efficiency of FDH. The analysis of the reactive trajectories also reveals how the relative movements of some amino acids, mainly His332 and Arg284, precede and promote the chemical reaction. In spite of these movements, the time-dependent evolution of the electric field created by the enzyme on the key atoms of the reaction reveals a permanent field, which reduces the work required to reach the transition state, with a concomitant polarization of the cofactor. Finally, application of Grote-Hynes theory has allowed the identification of the modes responsible for the substrate-environment coupling, showing how some protein motions take place simultaneously with the reaction. Thus, the equilibrium approach would provide, in this case, an overestimation of the catalyzed rate constant.
Institute of Scientific and Technical Information of China (English)
无
2011-01-01
Beam angular divergence is one of the indicators to evaluate the beam quality. Operating parameters of the beam extraction system could be adjusted to gain better beam quality following the measurement results, which will be helpful not only to study the transmission characteristics of the beam and the power distribution on the heat load components, but also to understand the real-time working condition of the ion source and beam extraction system. This study includes: (1) the theoretical analysis of beam extraction pulse duration for measurement of beam angular divergence; (2) the theoretical analysis of beam intensity distribution during beam transmission for Experimental Advanced Superconducting Tokomak (EAST) neutral beam injector. Those theoretical analyses could point the way to the measurement of beam divergence angle for EAST neutral beam injector.
Schwarcz, Yonatan; Schwarcz, Yael; Peleg, Eran; Joskowicz, Leo; Wollstein, Ronit; Luria, Shai
2017-01-18
Our goal was to analyze the movement of acute scaphoid waist fracture fragments and adjacent bones in a common coordinate system. Our hypothesis was that the distal scaphoid fragment flexes and pronates and the proximal fragment extends. Computed tomography (CT) scans of patients diagnosed with an acute scaphoid waist fracture were evaluated using a 3-dimensional (3D) model. The scans of 57 nondisplaced and 23 displaced fractures were compared with a control group of 27 scans showing no pathological involvement of the wrist. Three anatomical landmarks were labeled on the distal and proximal fragments of the scaphoid, the lunate, and the trapezium. Each set of labels formed a triangle representing the bone or fragment. Four landmarks were labeled on the distal radial articular surface and used to create a common coordinate system. The position of each bone or fragment was calculated in reference to these coordinates. The displaced fracture group showed significant extension, supination, and volar translation of the proximal scaphoid fragment when compared with the other groups. The lunate tended toward a supinated position, which was not statistically significant. The distal scaphoid fragment and the trapezium showed no movement. In acute displaced scaphoid fractures, it is the proximal fragment that displaces and should be reduced. The typical "humpback" deformity is actually a "proximal extension" deformity, the consequence of displacement of the proximal fragment of the scaphoid (with the lunate). Manipulating only the proximal fragment (with the lunate) may be technically easier and more effective than manipulating both fragments.
Determination of Lateral Extension of Hydrocarbon Concentration Sealing Caprocks by AVO Analysis
Institute of Scientific and Technical Information of China (English)
Li Weilian
2007-01-01
The caprock is one of the key factors for a reservoir, especially for a gas reservoir. Whether the caprocks can block off the gas is of significance for the accumulation and preservation of the gas reservoir. In this paper, we use the Amplitude versus offset (AVO) seismic technique to determine the lateral extension of the hydrocarbon concentration sealing caprocks. The essence of this technique is to detect the variations of the reservoir bed physical properties by monitoring the variations of the reflection coefficient of seismic waves upon the interfaces between different lithologies.Generally it is used to indicate hydrocarbon directly. For the hydrocarbon concentration sealing caprocks, the change of hydrocarbon concentration may cause the change of physical properties of the caprocks. Therefore it is possible to evaluate the hydrocarbon concentration sealing ability of the caprocks by AVO. This paper presents a case study using AVO to determine the lateral extension of the hydrocarbon concentration sealing caprocks. The result shows that this method is helpful for the exploration of the region.
Papadakis, Giorgos; Vallianatos, Filippos
2017-06-01
In a recent study, Papadakis et al. (Physica A 456: 135-144, 2016) investigate seismicity in Greece, using the non-extensive statistical physics formalism. Moreover, these authors examine the spatial distribution of the non-extensive parameter q M and show that for shallow seismicity, increase of q M coincides with strong events. However, their study also reveals low q M values along the North Aegean Trough, despite the presence of strong events during 1976-2009. Consequently, the present study further examines the temporal behaviour of parameters q M and A, to reveal their relation with the evolution of the earthquake sequence. Through temporal examination of these parameters, we aim to show that the seismogenic system of the North Aegean Trough presents high degree of interactions after strong earthquakes during the studied period. Our findings indicate that increase of q M signifies the existence of long-range correlations. If its value does not significantly decrease after a strong earthquake (i.e. M ≥ 5) then the studied area has not reached the state of equilibrium.
A regional comparative analysis of empirical and theoretical flood peak-volume relationships
Directory of Open Access Journals (Sweden)
Szolgay Ján
2016-12-01
Full Text Available This paper analyses the bivariate relationship between flood peaks and corresponding flood event volumes modelled by empirical and theoretical copulas in a regional context, with a focus on flood generation processes in general, the regional differentiation of these and the effect of the sample size on reliable discrimination among models. A total of 72 catchments in North-West of Austria are analysed for the period 1976–2007. From the hourly runoff data set, 25 697 flood events were isolated and assigned to one of three flood process types: synoptic floods (including long- and short-rain floods, flash floods or snowmelt floods (both rain-on-snow and snowmelt floods. The first step of the analysis examines whether the empirical peak-volume copulas of different flood process types are regionally statistically distinguishable, separately for each catchment and the role of the sample size on the strength of the statements. The results indicate that the empirical copulas of flash floods tend to be different from those of the synoptic and snowmelt floods. The second step examines how similar are the empirical flood peak-volume copulas between catchments for a given flood type across the region. Empirical copulas of synoptic floods are the least similar between the catchments, however with the decrease of the sample size the difference between the performances of the process types becomes small. The third step examines the goodness-of-fit of different commonly used copula types to the data samples that represent the annual maxima of flood peaks and the respective volumes both regardless of flood generating processes (the traditional engineering approach and also considering the three process-based classes. Extreme value copulas (Galambos, Gumbel and Hüsler-Reiss show the best performance both for synoptic and flash floods, while the Frank copula shows the best performance for snowmelt floods. It is concluded that there is merit in treating flood
Miyazaki, Ryoichi; Saruwatari, Hiroshi; Shikano, Kiyohiro
We propose a structure-generalized blind spatial subtraction array (BSSA), and the theoretical analysis of the amounts of musical noise and speech distortion. The structure of BSSA should be selected according to the application, i.e., a channelwise BSSA is recommended for listening but a conventional BSSA is suitable for speech recognition.
2009-01-01
Theoretical analysis of a CO2-NH3 cascade refrigeration system for cooling applications at low-temperatures correspondance: Corresponding author. Tel.: +34 986 812605; fax: +34 986 811995. (Fernandez-Seara, Jose) (Fernandez-Seara, Jose) Area de Maquinas y Motores Termicos--> , E.T.S. de Ingenieros Industriales--> , University of Vigo--> , Campus Lagoas-Marcosende No 9--> , 36310 Vigo--> ...
Morris-Kukoski, Cynthia L; Montgomery, Madeline A; Hammer, Rena L
2014-01-01
Samples from a self-proclaimed cocaine (COC) user, from 19 drug users (postmortem) and from 27 drug chemists were extensively washed and analyzed for COC, benzoylecgonine, norcocaine (NC), cocaethylene (CE) and aryl hydroxycocaines by liquid chromatography-tandem mass spectrometry. Published wash criteria and cutoffs were applied to the results. Additionally, the data were used to formulate new reporting criteria and interpretation guidelines for forensic casework. Applying the wash and reporting criteria, hair that was externally contaminated with COC was distinguished from hair collected from individuals known to have consumed COC. In addition, CE, NC and hydroxycocaine metabolites were only present in COC users' hair and not in drug chemists' hair. When properly applied, the use of an extended wash, along with the reporting criteria defined here, will exclude false-positive results from environmental contact with COC.
An in-depth analysis of theoretical frameworks for the study of care coordination1
Van Houdt, Sabine; Heyrman, Jan; Vanhaecht, Kris; Sermeus, Walter; De Lepeleire, Jan
2013-01-01
Introduction Complex chronic conditions often require long-term care from various healthcare professionals. Thus, maintaining quality care requires care coordination. Concepts for the study of care coordination require clarification to develop, study and evaluate coordination strategies. In 2007, the Agency for Healthcare Research and Quality defined care coordination and proposed five theoretical frameworks for exploring care coordination. This study aimed to update current theoretical frame...
An in-depth analysis of theoretical frameworks for the study of care coordination
Sabine Van Houdt; Jan Heyrman; Kris Vanhaecht; Walter Sermeus; Jan De Lepeleire
2013-01-01
Introduction: Complex chronic conditions often require long-term care from various healthcare professionals. Thus, maintaining quality care requires care coordination. Concepts for the study of care coordination require clarification to develop, study and evaluate coordination strategies. In 2007, the Agency for Healthcare Research and Quality defined care coordination and proposed five theoretical frameworks for exploring care coordination. This study aimed to update current theoretical fram...
Theoretical analysis of a pressure setting and control system with PWM direction control valve
Avram, M.; Duminică, D.; Cartal, L. A.
2016-08-01
The paper tackles theoretical aspects concerning an original automated system that sets and controls the pressure inside a tank chamber of fixed volume. The structure of the system integrates an original device developed and designed by the authors. The device digitally controls the one way flow of the working fluid using pulse width modulation, allowing the free flow in the other way. The purpose of this research stage was the theoretical establishing of the variation law of the pressure inside the controlled chamber.
Energy Technology Data Exchange (ETDEWEB)
Pittaluga, G.; Benvenuto, G. (Udine Univ. (Italy); L' Aquila Univ. (Italy))
1988-06-01
Relevant to experimental investigations on the performance of a transonic turbine blade cascade, this paper discusses recent developments regarding the following topics: the experimental equipment and relative instrumentation; the results of tests on turbine blade cascades; the conceptual methods specifically developed and aimed at the optimized design of steam turbines systems and turbine blades; the theoretical-numerical procedures developed and applied as supports for theoretical-experimental analyses and the redesign of blade profiles to increase efficiency.
Energy Technology Data Exchange (ETDEWEB)
Chang, S.J.
1997-05-01
The state of the vessel steel embrittlement as a result of neutron irradiation can be measured by its increase in the nil ductility temperature (NDT). This temperature is sometimes referred to as the brittle-ductile transition temperature (DBT) for fracture. The life extension of the High Flux Isotope Reactor (HFIR) vessel is calculated by using the method of fracture mechanics. A new method of fracture probability calculation is presented in this paper. The fracture probability as a result of the hydrostatic pressure test (hydrotest) is used to determine the life of the vessel. The hydrotest is performed in order to determine a safe vessel static pressure. It is then followed by using fracture mechanics to project the safe reactor operation time from the time of the satisfactory hydrostatic test. The life extension calculation provides the following information on the remaining life of the reactor as a function of the NDT increase: (1) the life of the vessel is determined by the probability of vessel fracture as a result of hydrotest at several hydrotest pressures and vessel embrittlement conditions, (2) the hydrotest time interval vs the NDT increase rate, and (3) the hydrotest pressure vs the NDT increase rate. It is understood that the use of a complete range of uncertainties of the NDT increase is equivalent to the entire range of radiation damage that can be experienced by the vessel steel. From the numerical values for the probabilities of the vessel fracture as a result of hydrotest, it is estimated that the reactor vessel life can be extended up to 50 EFPY (100 MW) with the minimum vessel operating temperature equal to 85{degrees}F.
Theoretical analysis of non-Gaussian heterogeneity effects on subsurface flow and transport
Riva, Monica; Guadagnini, Alberto; Neuman, Shlomo P.
2017-04-01
Much of the stochastic groundwater literature is devoted to the analysis of flow and transport in Gaussian or multi-Gaussian log hydraulic conductivity (or transmissivity) fields, Y(x)=ln\\func K(x) (x being a position vector), characterized by one or (less frequently) a multiplicity of spatial correlation scales. Yet Y and many other variables and their (spatial or temporal) increments, ΔY, are known to be generally non-Gaussian. One common manifestation of non-Gaussianity is that whereas frequency distributions of Y often exhibit mild peaks and light tails, those of increments ΔY are generally symmetric with peaks that grow sharper, and tails that become heavier, as separation scale or lag between pairs of Y values decreases. A statistical model that captures these disparate, scale-dependent distributions of Y and ΔY in a unified and consistent manner has been recently proposed by us. This new "generalized sub-Gaussian (GSG)" model has the form Y(x)=U(x)G(x) where G(x) is (generally, but not necessarily) a multiscale Gaussian random field and U(x) is a nonnegative subordinator independent of G. The purpose of this paper is to explore analytically, in an elementary manner, lead-order effects that non-Gaussian heterogeneity described by the GSG model have on the stochastic description of flow and transport. Recognizing that perturbation expansion of hydraulic conductivity K=eY diverges when Y is sub-Gaussian, we render the expansion convergent by truncating Y's domain of definition. We then demonstrate theoretically and illustrate by way of numerical examples that, as the domain of truncation expands, (a) the variance of truncated Y (denoted by Yt) approaches that of Y and (b) the pdf (and thereby moments) of Yt increments approach those of Y increments and, as a consequence, the variogram of Yt approaches that of Y. This in turn guarantees that perturbing Kt=etY to second order in σYt (the standard deviation of Yt) yields results which approach those we obtain
Extension of an Object Oriented Multidisciplinary Analysis Optimization (MDAO) Environment Project
National Aeronautics and Space Administration — Multidisciplinary design, analysis, and optimization (MDAO) tools today possess limited disciplines with little fidelity modeling capability. These tools are...
Theoretical Analysis of Bubble Nucleation in Molten Steel Supersaturated with Nitrogen or Hydrogen
Li, Kangwei; Liu, Jianhua; Zhang, Jie; Shen, Shaobo
2017-08-01
The nucleation of bubbles in molten steel supersaturated with nitrogen or hydrogen was studied based on the theory of classical solidification nucleation. The mathematical models of critical radii for homogeneous and heterogeneous nucleation processes were derived. The results show that these critical radii are identical, but the volume of the bubble formed via the heterogeneous nucleation is only part of the spherical volume of the bubble formed via the homogeneous nucleation. Thus, the bubbles easily undergo heterogeneous nucleation on the surface of inclusions with poor wettability in molten steel. The effects of melt depth, nitrogen- or hydrogen-pretreatment pressure, and vacuum-treatment pressure on the critical-nucleation radius were studied based on the models derived. The results show that when the molten liquid is pretreated using nitrogen or hydrogen at 1 bar and, subsequently, treated at a vacuum pressure of 10-3 bar and a temperature of 1873 K (1600 °C), the bubbles nucleate spontaneously if the melt depth is below 0.39 m. Moreover, when the melt depths are 0.39 and 1.09 m, the critical-nucleation radii are 0 and 100 μm, respectively. When the melt depth is above 1.09 m, the critical-nucleation radius is greater than 100 μm. The critical melt depth for spontaneous nucleation and formation of different sizes of bubble nuclei increases when the molten steel is treated with nitrogen or hydrogen at a higher pretreatment pressure. However, the effects of the vacuum-treatment pressure on the critical melt depth for spontaneous nucleation and formation of different sizes of bubble nuclei are negligible. The experiments performed in this study helped in confirming part of the results of the theoretical analysis.
Energy Technology Data Exchange (ETDEWEB)
Monárrez-Cordero, B.E.; Amézaga-Madrid, P., E-mail: patricia.amezaga@cimav.edu.mx; Hernández-Salcedo, P.G.; Antúnez-Flores, W.; Leyva-Porras, C.; Miki-Yoshida, M.
2014-12-05
Highlights: • High purity mesoporous hollow magnetite nanoparticles were synthesized by AACVD. • Microstructural characteristics strongly depends on the synthesis conditions. • Activation energy of −159 kJ mol{sup −1} was obtained from thermogravimetric analyses of FeCl{sub 2.} • Simulation of concentration distribution of reactants and products was realized. • Simulated and experimental magnetite production rate agreed around 2 × 10{sup −5} mol h{sup −1}. - Abstract: Nowadays, mesoporous magnetite nanoparticles are an important class of new nanomaterials which occupy a valuable position in materials science. Owing to their several advantages over bulk magnetite and particularly with respect to higher adsorption capacity, there is a growing interest towards the use of these materials for the adsorptive removal of a variety of contaminants, including organic dyes from wastewater. Through aerosol assisted chemical vapor deposition (AACVD) technique is possible to synthesize spherical hollow nanoparticles with external diameter from 50 to 500 nm, composed of a shell of crystallites smaller than 30 nm. In the AACVD method, the structural morphology of resultant nanoparticles strongly depends on the starting precursors and operating conditions. Some advantages of this technique are the high production rate, continuous operation, use of relatively simple equipment, easy doping and the possibility to scale the process industrially. Therefore, in order to understand the formation of magnetite nanoparticles by AACVD, theoretical simulations were performed on two important steps of the synthesis: (i) temperature and carrier gas flow distribution inside of tubular reactor, and (ii) the distribution of molar concentration of the precursor in the synthesis process. Reaction kinetics of the precursor was studied to determine Arrhenius parameters. Activation energy and pre-exponential factor were calculated experimentally from thermal analysis, these values
Obstacles to patient education in chronic diseases: a trans-theoretical analysis.
Reach, Gérard
2009-11-01
The aim of this article is to discuss the background and the consequences of preference on short-term rewards by individuals, which represents an obstacle to any educational programme aimed to prevent long-term complications of chronic diseases such as diabetes, hypertension or obesity. We used a trans-theoretical analysis referring to three theories: (1) Construal Level Theory (Trope and Liberman) suggests that the human mind tends to assign remote events as "high-level" criteria, abstraction, in particular, and to proximal events as "low-level" criteria, a concrete description, in particular. (2) Intertemporal Choice Theory (Ainslie) explains why people often prefer short-term small rewards over long-term large rewards. (3) The theory developed by Parfit suggests that the personal identity of human beings is made of a succession of multiple individuals, in time, who find their identity by the fact that there is a connectedness between them. Since this connectedness is weaker for prolonged periods of time, this Personal Identity Theory may explain why we may be less interested in our future. In the minds of people who are supposed to benefit from such programmes, there may be a striking contrast between the objectives of preventive medicine (typically a high-level construal), which represents an abstract and long-term concept (e.g. "to avoid complications"), and that of the representation of inaction, a low-level construal which is by contrast immediate and concrete and can be readily imagined (e.g. a nap in front of the TV set). The very concept of prevention entails features that jeopardize the efficiency of educational programmes used for its implementation. (1) In chronic diseases, designing programmes proposing concrete and short-term preventive measures may represent a way to overcome this obstacle. (2) Habit may be used to reinforce connectedness which forms personal identity. (3) Thus, taking into account this temporal dimension of educational programmes
Graph theoretical analysis indicates cognitive impairment in MS stems from neural disconnection.
Van Schependom, Jeroen; Gielen, Jeroen; Laton, Jorne; D'hooghe, Marie B; De Keyser, Jacques; Nagels, Guy
2014-01-01
The mechanisms underlying cognitive impairment in MS are still poorly understood. However, due to the specific pathology of MS, one can expect alterations in connectivity leading to physical and cognitive impairment. In this study we aimed at assessing connectivity differences in EEG between cognitively impaired (CI) and cognitively preserved (CP) MS patients. We also investigated the influence of the measures used to construct networks. We included 308 MS patients and divided them into two groups based on their cognitive score. Graph theoretical network analyses were conducted based on networks constructed using different connectivity measures, i.e. correlation, correlation in the frequency domain, coherence, partial correlation, the phase lag index and the imaginary part of coherency. The most commonly encountered network parameters were calculated and compared between the two groups using Wilcoxon's rank test. Clustering coefficients and path lengths were normalized to a randomized mean clustering coefficient and path length for each patient. False discovery rate was used to correct for the multiple comparisons and Cohen's d effect sizes are reported. Coherence analysis suggests that theta and delta connectivity is significantly smaller in cognitively impaired patients. Small-worldness differences are found in networks based on correlation, theta and delta coherence and correlation in the frequency domain. Modularity was related to age but not to cognition. Cognitive deterioration in MS is a symptom that seems to be caused by neural disconnections, probably the white matter tracts connecting both hemispheres, and leads to a wide range in network differences which can be assessed by applying GTA to EEG data. In the future, these results may lead to cheaper and more objective assessments of cognitive impairment in MS.
Agibalov, D. Y.; Panchenkov, D. N.; Chertyuk, V. B.; Leonov, S. D.; Astakhov, D. A.
2017-01-01
The liver failure which is result of disharmony of functionality of a liver to requirements of an organism is the main reason for unsatisfactory results of an extensive resection of a liver. However, uniform effective criterion of definition of degree of a liver failure it isn’t developed now. One of data acquisition methods about a morfo-functional condition of internals is the bioimpedance analysis (BIA) based on impedance assessment (full electric resistance) of a biological tissue. Measurements of an impedance are used in medicine and biology for the characteristic of physical properties of living tissue, studying of the changes bound to a functional state and its structural features. In experimental conditions we carried out an extensive resection of a liver on 27 white laboratory rats of the Vistar line. The comparative characteristic of data of a bioimpedansometriya in intraoperative and after the operational period with the main existing methods of assessment of a functional condition of a liver was carried out. By results of the work performed by us it is possible to claim that the bioimpedance analysis of a liver on the basis of an invasive bioimpedansometriya allows to estimate morphological features and functional activity of a liver before performance of an extensive resection of a liver. The data obtained during scientific work are experimental justification for use of an impedansometriya during complex assessment of functional reserves of a liver. Preliminary data of clinical approbation at a stage of introduction of a technique speak about rather high informational content of a bioimpedansometriya. The subsequent analysis of efficiency of the invasive bioimpedance analysis of a liver requires further accumulation of clinical data. However even at this stage the method showed the prospect for further use in clinical surgical hepathology.
Institute of Scientific and Technical Information of China (English)
CAO Guo-yun; ZHANG Qing; CHUNG T S; CHEN Chen
2008-01-01
Properties of the active power/angle sub-matrix in the power flow Jacobian for power system analysis are studied. The sub-matrix is a dominant and irreducible matrix under very general conditions of power systems, so that it is invertible. Also the necessary conditions for its singularity are given. These theoretical rsuts can be used to clarify the ambiguous understanding of the sub-matrix in current literature, and also provide the theoretical foundations for the applications based on reduced power flow Jacobian. Numerical simulation on the IEEE 118-bus power system is used to illustrate our results.
Niu, X. D.; Shu, C.; Chew, Y. T.
A Lattice Boltzmann model for simulating micro flows has been proposed by us recently (Europhysics Letters, 67(4), 600-606 (2004)). In this paper, we will present a further theoretical and numerical validation of the model. In this regards, a theoretical analysis of the diffuse-scattering boundary condition for a simple flow is carried out and the result is consistent with the conventional slip velocity boundary condition. Numerical validation is highlighted by simulating the two-dimensional isothermal pressure-driven micro-channel flows and the thin-film gas bearing lubrication problems, and comparing the simulation results with available experimental data and analytical predictions.
Cormanich, Rodrigo A; Ducati, Lucas C; Tormena, Cláudio F; Rittner, Roberto
2014-04-01
Amino acid conformational analysis in solution are scarce, since these compounds present a bipolar zwitterionic structure ((+)H3NCHRCOO(-)) in these media. Also, intramolecular hydrogen bonds have been classified as the sole interactions governing amino acid conformational behavior in the literature. In the present work we propose phenylalanine and tyrosine methyl ester conformational studies in different solvents by (1)H NMR and infrared spectroscopies and theoretical calculations. Both experimental and theoretical results are in agreement and suggest that the conformational behavior of the phenylalanine and tyrosine methyl esters are similar and are dictated by the interplay between steric and hyperconjugative interactions.
Directory of Open Access Journals (Sweden)
Rouet Fabien
2009-10-01
Full Text Available Abstract Background Commercially available microarrays have been used in many settings to generate expression profiles for a variety of applications, including target selection for disease detection, classification, profiling for pharmacogenomic response to therapeutics, and potential disease staging. However, many commercially available microarray platforms fail to capture transcript diversity produced by alternative splicing, a major mechanism for driving proteomic diversity through transcript heterogeneity. Results The human Genome-Wide SpliceArray™ (GWSA, a novel microarray platform, utilizes an existing probe design concept to monitor such transcript diversity on a genome scale. The human GWSA allows the detection of alternatively spliced events within the human genome through the use of exon body and exon junction probes to provide a direct measure of each transcript, through simple calculations derived from expression data. This report focuses on the performance and validation of the array when measured against standards recently published by the Microarray Quality Control (MAQC Project. The array was shown to be highly quantitative, and displayed greater than 85% correlation with the HG-U133 Plus 2.0 array at the gene level while providing more extensive coverage of each gene. Almost 60% of splice events among genes demonstrating differential expression of greater than 3 fold also contained extensive splicing alterations. Importantly, almost 10% of splice events within the gene set displaying constant overall expression values had evidence of transcript diversity. Two examples illustrate the types of events identified: LIM domain 7 showed no differential expression at the gene level, but demonstrated deregulation of an exon skip event, while erythrocyte membrane protein band 4.1 -like 3 was differentially expressed and also displayed deregulation of a skipped exon isoform. Conclusion Significant changes were detected independent of
Theoretical and Experimental Aerodynamic Analysis for High-Speed Ground Vehicles
Farhan, Ismail Haider
Available from UMI in association with The British Library. This thesis investigates the air flow around a proposed geometry for a high-speed electromagnetic suspension (EMS) train. A numerical technique called the panel method has been applied to the representation of the body shape and the prediction of the potential flow and pressure distribution. Two computer programmes have been written, one for a single vehicle in the presence of the ground at different yaw angles, and the second for two-body problems, e.g. a train passing a railway station or a train passing the central part of another train. Two methods based on the momentum integral equations for three-dimensional boundary layer flow have been developed for use with the potential flow analysis; these predict the development of the three-dimensional turbulent boundary layer on the central section (for the analysis of crosswind conditions) and on the nose of the train. Extensive wind tunnel tests were performed on four models of the high-speed train to measure aerodynamic forces, moments and pressures to establish ground effect characteristics. Flow visualisation showed that the wake vortices were stronger and larger in the presence of a ground. At small yaw angles ground clearance had little effect, but as yaw increased, larger ground clearance led to substantial increase in lift and side force coefficients. The tests also identified the differences between a moving and a fixed ground plane. Data showed that the type of ground simulation was significant only in the separated region. A comparison of the results predicted using potential flow theory for an EMS train model and the corresponding results from wind tunnel tests indicated good agreement in regions where the flow is attached. The turbulent boundary layer calculations for the train in a crosswind condition showed that the momentum thickness along the crosswind surface distance co-ordinate increased slowly at the beginning of the development of the
Zhu, Yuan O.; Sherlock, Gavin; Petrov, Dmitri A.
2016-01-01
Budding yeast has undergone several independent transitions from commercial to clinical lifestyles. The frequency of such transitions suggests that clinical yeast strains are derived from environmentally available yeast populations, including commercial sources. However, despite their important role in adaptive evolution, the prevalence of polyploidy and aneuploidy has not been extensively analyzed in clinical strains. In this study, we have looked for patterns governing the transition to clinical invasion in the largest screen of clinical yeast isolates to date. In particular, we have focused on the hypothesis that ploidy changes have influenced adaptive processes. We sequenced 144 yeast strains, 132 of which are clinical isolates. We found pervasive large-scale genomic variation in both overall ploidy (34% of strains identified as 3n/4n) and individual chromosomal copy numbers (36% of strains identified as aneuploid). We also found evidence for the highly dynamic nature of yeast genomes, with 35 strains showing partial chromosomal copy number changes and eight strains showing multiple independent chromosomal events. Intriguingly, a lineage identified to be baker’s/commercial derived with a unique damaging mutation in NDC80 was particularly prone to polyploidy, with 83% of its members being triploid or tetraploid. Polyploidy was in turn associated with a >2× increase in aneuploidy rates as compared to other lineages. This dataset provides a rich source of information on the genomics of clinical yeast strains and highlights the potential importance of large-scale genomic copy variation in yeast adaptation. PMID:27317778
Energy Technology Data Exchange (ETDEWEB)
Helfer, Thomas
2015-07-15
Highlights: • A simple extension of standard monodimensional fuel performance codes to finite strain is proposed. • Efficiency and reliability are demonstrated. • The logarithmic strain frameword proposed by Miehe et al. is introduced and discussed. - Abstract: This paper shows how the Lagrangian logarithmic strain framework proposed by Miehe et al. can be used to extend monodimensional fuel performance codes, written in the framework of the infinitesimal strain theory, to be able to cope with large deformation of the cladding, such as the ones observed in reactivity initiated accidents (RIA) or loss-of-coolant accidents (LOCA). We demonstrate that the changes only concern the mechanical behaviour integration step by a straightforward modification of the strains (inputs) and the stress (result). The proposed procedure has been implemented in the open-source MFront code generator developed within the PLEIADES platform to handle mechanical behaviours. Using the Alcyone performance code, we apply this procedure to a simulation case proposed within the framework of a recent benchmark on fuel performance codes by the OECD/NEA.
Shu, Ting; Zhang, Bob; Yan Tang, Yuan
2017-04-01
Researchers have recently discovered that Diabetes Mellitus can be detected through non-invasive computerized method. However, the focus has been on facial block color features. In this paper, we extensively study the effects of texture features extracted from facial specific regions at detecting Diabetes Mellitus using eight texture extractors. The eight methods are from four texture feature families: (1) statistical texture feature family: Image Gray-scale Histogram, Gray-level Co-occurance Matrix, and Local Binary Pattern, (2) structural texture feature family: Voronoi Tessellation, (3) signal processing based texture feature family: Gaussian, Steerable, and Gabor filters, and (4) model based texture feature family: Markov Random Field. In order to determine the most appropriate extractor with optimal parameter(s), various parameter(s) of each extractor are experimented. For each extractor, the same dataset (284 Diabetes Mellitus and 231 Healthy samples), classifiers (k-Nearest Neighbors and Support Vector Machines), and validation method (10-fold cross validation) are used. According to the experiments, the first and third families achieved a better outcome at detecting Diabetes Mellitus than the other two. The best texture feature extractor for Diabetes Mellitus detection is the Image Gray-scale Histogram with bin number=256, obtaining an accuracy of 99.02%, a sensitivity of 99.64%, and a specificity of 98.26% by using SVM. Copyright © 2017 Elsevier Ltd. All rights reserved.
Measuring health lifestyles in a comparative analysis: theoretical issues and empirical findings.
Abel, T
1991-01-01
The concept of lifestyle bears great potential for research in medical sociology. Yet, weaknesses in current methods have restrained lifestyle research from realizing its full potentials. The present focus is on the links between theoretical conceptions and their empirical application. The paper divides into two parts. The first part provides a discussion of basic theoretical and methodological issues. In particular selected lines of thought from Max Weber are presented and their usefulness in providing a theoretical frame of reference for health lifestyle research is outlined. Next, a theory guided definition of the subject matter is introduced and basic problems in empirical applications of theoretical lifestyle concepts are discussed. In its second part the paper presents findings from comparative lifestyle analyses. Data from the U.S. and West Germany are utilized to explore issues of measurement equivalence and theoretical validity. Factor analyses indicate high conceptual equivalence for new measures of health lifestyle dimensions in both the U.S. and West Germany. Divisive cluster analyses detect three distinct lifestyle groups in both nations. Implications for future lifestyle research are discussed.
Directory of Open Access Journals (Sweden)
Alexandre Almeida
2015-02-01
Full Text Available OBJECTIVE: To analyze the results from arthroscopic suturing of large and extensive rotator cuff injuries, according to the patient's degree of osteopenia.METHOD: 138 patients who underwent arthroscopic suturing of large and extensive rotator cuff injuries between 2003 and 2011 were analyzed. Those operated from October 2008 onwards formed a prospective cohort, while the remainder formed a retrospective cohort. Also from October 2008 onwards, bone densitometry evaluation was requested at the time of the surgical treatment. For the patients operated before this date, densitometry examinations performed up to two years before or after the surgical treatment were investigated. The patients were divided into three groups. Those with osteoporosis formed group 1 (n = 16; those with osteopenia, group 2 (n = 33; and normal individuals, group 3 (n = 55.RESULTS: In analyzing the University of California at Los Angeles (UCLA scores of group 3 and comparing them with group 2, no statistically significant difference was seen (p = 0.070. Analysis on group 3 in comparison with group 1 showed a statistically significant difference (p = 0.027.CONCLUSION: The results from arthroscopic suturing of large and extensive rotator cuff injuries seem to be influenced by the patient's bone mineral density, as assessed using bone densitometry.
Energy Technology Data Exchange (ETDEWEB)
Raebiger, K. [LEISTRITZ Pumpen GmbH, Nuremberg (Germany); Faculty of Advanced Technology, University of Glamorgan, Pontypridd, Wales (United Kingdom); Maksoud, T.M.A.; Ward, J. [Faculty of Advanced Technology, University of Glamorgan, Pontypridd, Wales (United Kingdom); Hausmann, G. [Department of Mechanical Engineering and Building Services Engineering, University of Applied Sciences, Nuremberg (Germany)
2008-09-15
In the investigation of the pumping behaviour of multiphase screw pumps, handling gas-liquid mixtures with very high gas volume fractions, theoretical and experimental analyses were performed. A new theoretical screw pump model was developed, which calculates the time-dependent conditions inside the several chambers of a screw pump as well as the exchange of mass and energy between these chambers. By means of the performed experimental analysis, the screw pump model was verified, especially at very high gas volume fractions from 90% to 99%. The experiments, which were conducted with the reference fluids water and air, can be divided mainly into the determination of the steady state pumping behaviour on the one hand and into the analysis of selected transient operating conditions on the other hand, whereas the visualisation of the leakage flows through the circumferential gaps was rounded off the experimental analysis. (author)
A new theoretical model of the quasistatic single-fiber pullout problem: Analysis of stress field
DEFF Research Database (Denmark)
Qing, Hai
2013-01-01
results of the stress distributions, in both fully bonded region and fully debonded region, are presented for a typical glass/epoxy composite system with different fibre volume fraction and model length. In fully bonded region, the theoretical results from present model are more accurate compared......A new theoretical model is developed in order to predict the stress transfer during the quasistatic single-fibre pullout process. The theoretical approach retains all relevant stress and strain components, and satisfies exactly the interfacial continuity conditions and all the stress boundary...... conditions. For both matrix and fibre, the equilibrium equations along radial direction are satisfied strictly, while the equilibrium equations along axial direction are satisfied in the integral forms. Three normal stress-strain relationships are strictly satisfied, while the radial displacement gradient...
Theoretical Calculation and Analysis of Slip and Deformation for Concrete Sandwich Panels
Institute of Scientific and Technical Information of China (English)
LI Yanbo; ZHANG Shaohua; XIA Baoyang
2007-01-01
Slip and deformation of concrete sandwich panels under uniformly distributed loads is concerned. The effect of slip on the deformation of concrete sandwich panels are studied, and the analytical expressions of slip and deformation for concrete sandwich panels is obtained. These formulae can describe the slip distribution and account for its effect on deformation. In order to restrict the bound of formula, the formula of crack moment is obtained. The results of theoretical calculation are compared with those of tests and finite element methods. The comparison shows that the results of theoretical calculation are in accord with those of tests and finite element methods. So the theoretical calculation can be used to calculate slip and deformation of concrete sandwich panels in practical projects.
Theoretical and Experimental Analysis of Adsorption in Surface-based Biosensors
DEFF Research Database (Denmark)
Hansen, Rasmus
The present Ph.D. dissertation concerns the application of surface plasmon resonance (SPR) spectroscopy, which is a surface-based biosensor technology, for studies of adsorption dynamics. The thesis contains both experimental and theoretical work. In the theoretical part we develop the theory...... for convection, diffusion, and adsorption in surface-based biosensors in general. In particular, we study the transport dynamics in a model geometry of a Biacore SPR sensor. An approximate quasi-steady theory, which has been widely adopted in the SPR literature to capture convective and diffusive mass transport...... is critical for reliable use of the quasi-steady theory. Our theoretical results provide users of surface-based biosensors with a tool of correcting experimentally obtained adsorption rate constants, based on the quasisteady theory. Finally, the consequence of adsorption on all surfaces present in the flow...
A quantum-information theoretic analysis of three-flavor neutrino oscillations
Energy Technology Data Exchange (ETDEWEB)
Banerjee, Subhashish, E-mail: subhashish@iitj.ac.in; Alok, Ashutosh Kumar, E-mail: akalok@iitj.ac.in [Indian Institute of Technology Jodhpur, 342011, Jodhpur (India); Srikanth, R., E-mail: srik@poornaprajna.org [Poornaprajna Institute of Scientific Research, Sadashivnagar, 560080, Banglore (India); Hiesmayr, Beatrix C., E-mail: Beatrix.Hiesmayr@univie.ac.at [University of Vienna, Boltzmanngasse 5, 1090, Vienna (Austria)
2015-10-13
Correlations exhibited by neutrino oscillations are studied via quantum-information theoretic quantities. We show that the strongest type of entanglement, genuine multipartite entanglement, is persistent in the flavor changing states. We prove the existence of Bell-type nonlocal features, in both its absolute and genuine avatars. Finally, we show that a measure of nonclassicality, dissension, which is a generalization of quantum discord to the tripartite case, is nonzero for almost the entire range of time in the evolution of an initial electron-neutrino. Via these quantum-information theoretic quantities, capturing different aspects of quantum correlations, we elucidate the differences between the flavor types, shedding light on the quantum-information theoretic aspects of the weak force.
Institute of Scientific and Technical Information of China (English)
无
2011-01-01
The micromechanical behaviors and mechanics-optics coupling effects of optic-fiber-concrete complex in the distributed optic-fiber sensing concrete-crack technology,which was used in health monitoring of Wu Gorge Bridge on Yangtze River and a large dam successfully,have been investigated.A micromechanical theoretical analysis method and micromechanical frictional contact bi-interface model,as well as a modified optical theoretical analysis method of the mechanics-optics coupling effects are presented.A series of verification experiments,including mechanical experiments and mechanics-optics coupling experiments,have been preformed.The results of micromechanical theoretical analysis and the analysis of the modified theory of mechanics-optics coupling along with mechanical and optical experimental data are shown to be in close agreement.Both the micromechanical theory and the modified theory of mechanics-optics coupling with their analysis methods can not only enhance credibility of this novel distributed sensing technology but also provide a way to understand its sensing mechanism and optimize its technical details and system.
Li, Yan-Hui; Zhang, Gai-Gai
2016-01-01
DAF-16, the C. elegans FOXO transcription factor, is an important determinant in aging and longevity. In this work, we manually curated FOXODB http://lyh.pkmu.cn/foxodb/, a database of FOXO direct targets. It now covers 208 genes. Bioinformatics analysis on 109 DAF-16 direct targets in C. elegans found interesting results. (i) DAF-16 and transcription factor PQM-1 co-regulate some targets. (ii) Seventeen targets directly regulate lifespan. (iii) Four targets are involved in lifespan extension induced by dietary restriction. And (iv) DAF-16 direct targets might play global roles in lifespan regulation. PMID:27027346
Institute of Scientific and Technical Information of China (English)
邓松圣; 周绍骑; 廖振方; 邱正阳; 曾顺鹏
2004-01-01
Hydraulic transient,which is resulted from sudden increase of inlet pressure for laminar pipeline flow,is studied.The partial differential equation,initial and boundary conditions for transient pressure were constructed,and the theoretical solution was obtained by variable-separation method.The partial differential equation,initial and boundary conditions for flow rate were obtained in accordance with the constraint correlation between flow rate and pressure while the transient flow rate distribution was also solved by variable-separation method.The theoretical solution conforms to numerical solution obtained by method of characteristics(MOC)very well.
Engineering design and theoretical analysis of nanoporous carbon membranes for gas separation
Acharya, Madhav
1999-11-01
Gases are used in a direct or indirect manner in virtually every major industry, such as steel manufacturing, oil production, foodstuffs and electronics. Membranes are being investigated as an alternative to established methods of gas separation such as pressure swing adsorption and cryogenic distillation. Membranes can be used in continuous operation and work very well at ambient conditions, thus representing a tremendous energy and economic saving over the other technologies. In addition, the integration of reaction and separation into a single unit known as a membrane reactor has the potential to revolutionize the chemical industry by making selective reactions a reality. Nanoporous carbons are highly disordered materials obtained from organic polymers or natural sources. They have the ability to separate gas molecules by several different mechanisms, and hence there is a growing effort to form them into membranes. In this study, nanoporous carbon membranes were prepared on macroporous stainless steel supports of both tubular and disk geometries. The precursor used was poly(furfuryl alcohol) and different synthesis protocols were employed. A spray coating method also was developed which allowed reproducible synthesis of membranes with very few defects. High gas selectivities were obtained such as O2/N2 = 6, H2/C2H 4 = 70 and CO2/N2 = 20. Membranes also were characterized using SEM and AFM, which revealed thin layers of carbon that were quite uniform and homogeneous. The simulation of nanoporous carbon structures also was carried out using a simple algorithmic approach. 5,6 and 7-membered rings were introduced into the structure, thus resulting in considerable curvature. The density of the structures were calculated and found to compare favorably with experimental findings. Finally, a theoretical analysis of size selective transport was performed using transition state theory concepts. A definite correlation of gas permeance with molecular size was obtained after
Underwood, Mair
2014-04-01
It is increasingly recognized that community attitudes impact on the research trajectory, entry, and reception of new biotechnologies. Yet biogerontologists have generally been dismissive of public concerns about life extension. There is some evidence that biogerontological research agendas have not been communicated effectively, with studies finding that most community members have little or no knowledge of life extension research. In the absence of knowledge, community members' attitudes may well be shaped by issues raised in popular portrayals of life extension (e.g., in movies). To investigate how popular portrayals of life extension may influence community attitudes, I conducted an analysis of 19 films depicting human life extension across different genres. I focussed on how the pursuit of life extension was depicted, how life extension was achieved, the levels of interest in life extension shown by characters in the films, and the experiences of extended life depicted both at an individual and societal level. This paper compares the results of this analysis with the literature on community attitudes to life extension and makes recommendations about the issues in which the public may require reassurance if they are to support and accept life extension technologies.
Comprehensive analysis of RNA-Seq data reveals extensive RNA editing in a human transcriptome
DEFF Research Database (Denmark)
Peng, Zhiyu; Cheng, Yanbing; Tan, Bertrand Chin-Ming
2012-01-01
RNA editing is a post-transcriptional event that recodes hereditary information. Here we describe a comprehensive profile of the RNA editome of a male Han Chinese individual based on analysis of ∼767 million sequencing reads from poly(A)(+), poly(A)(-) and small RNA samples. We developed a comput...
An ACE-based Nonlinear Extension to Traditional Empirical Orthogonal Function Analysis
DEFF Research Database (Denmark)
Hilger, Klaus Baggesen; Nielsen, Allan Aasbjerg; Andersen, Ole;
2001-01-01
This paper shows the application of the empirical orthogonal unctions/principal component transformation on global sea surface height and temperature data from 1996 and 1997. A nonlinear correlation analysis of the transformed data is proposed and performed by applying the alternating conditional...
DEFF Research Database (Denmark)
Poel, Mike van der; Gehrig, Edeltraud; Hess, Ortwin;
2005-01-01
Ultrafast gain dynamics in an optical amplifier with an active layer of self-organized quantum dots (QDs) emitting near 1.3$muhbox m$is characterized experimentally in a pump-probe experiment and modeled theoretically on the basis of QD Maxwell–Bloch equations. Experiment and theory are in good...
Theoretical analysis of an iron mineral-based magnetoreceptor model in birds
DEFF Research Database (Denmark)
Solov'yov, Ilia; Greiner, Walter
2007-01-01
involves two types of iron minerals (magnetite and maghemite) that were found in subcellular compartments within sensory dendrites of the upper beak of several bird species. But so far a quantitative evaluation of the proposed receptor is missing. In this article, we develop a theoretical model...
A Preliminary Theoretical Analysis of a Research Experience for Undergraduates Community Model
Castillo-Garsow, Carlos; Castillo-Chavez, Carlos; Woodley, Sherry
2013-01-01
The Mathematical and Theoretical Biology Institute (MTBI) is a successful summer research experience for undergraduates, with a strong record of mentoring Ph.D. graduates, particularly, underrepresented minority students. However, the MTBI program was designed for education in research, not for research in education, and the mechanisms of the…
An Optimality-Theoretic Analysis of Scandinavian Object Shift and Remnant VP-Topicalisation
DEFF Research Database (Denmark)
Engels, Eva; Vikner, Sten
2006-01-01
to be violable and to interact with various constraints on movement in an Optimality-theoretic fashion, we suggest an account for various asymmetries in the interaction between remnant VP-topicalisations and both OS and other movement operations (especially subject raising) as to their order preserving...
A theoretical analysis of time-dependent fragment momenta in indirect photofragmentation
DEFF Research Database (Denmark)
Henriksen, Niels Engholm
2010-01-01
We study theoretically diatomic molecules which are prepared in a superposition of quasibound resonance states by a femtosecond laser pulse. An analytical (Landau–Zener-like) result is derived for the momentum distribution of the atomic fragments in the asymptotic force-free region after a single...
DEFF Research Database (Denmark)
Søndergaard, Thomas; Arentoft, Jesper
2002-01-01
A planar photonic crystal waveguide based on the semiconductor-on-insulator (SOI) materials system is analyzed theoretically. Two-dimensional (2-D) calculations and comparison with dispersion relations for the media above and below the finite-height waveguide are used to obtain design guidelines...
Directory of Open Access Journals (Sweden)
Boqi Song
2016-11-01
Full Text Available Perforated wooden panels are typically utilized as a resonant sound absorbing material in indoor noise control. In this paper, the absorption properties of wooden panels perforated with tiny holes of 1–3 mm diameter were studied both experimentally and theoretically. The Maa-MPP (micro perforated panels model and the Maa-Flex model were applied to predict the absorption regularities of finely perforated wooden panels. A relative impedance comparison and full-factorial experiments were carried out to verify the feasibility of the theoretical models. The results showed that the Maa-Flex model obtained good agreement with measured results. Control experiments and measurements of dynamic mechanical properties were carried out to investigate the influence of the wood characteristics. In this study, absorption properties were enhanced by sound-induced vibration. The relationship between the dynamic mechanical properties and the panel mass-spring vibration absorption was revealed. While the absorption effects of wood porous structure were not found, they were demonstrated theoretically by using acoustic wave propagation in a simplified circular pipe with a suddenly changed cross-section model. This work provides experimental and theoretical guidance for perforation parameter design.
A Historical Analysis of Academic Development Using the Theoretical Lens of Pierre Bourdieu
Kloot, Bruce Charles
2015-01-01
This paper provides a history of academic development by examining how a South African institution coped with the potent social forces confronting it before the collapse of apartheid. Theoretically, it draws on the framework of Pierre Bourdieu and engages with a paper written a decade ago by Naidoo, who also used Bourdieu to understand…
A theoretical and experimental analysis of modulated laser fields and power spectra
DEFF Research Database (Denmark)
Olesen, Henning; Jacobsen, G.
1982-01-01
A general theoretical description of modulated laser fields and power spectra for a current modulated single-mode laser is derived, taking into account both the intensity and frequency modulation (IM and FM) of the emitted light. The theory relies on an explicit knowledge of the modulus as well...
Theoretical Analysis of Measurement in Operation Efficiency in Optical Cable Transmission Networks
Institute of Scientific and Technical Information of China (English)
无
2000-01-01
It is necessary to study dynamic operation efficiency of transmission networks in order to realize high intensification of communication networks. The operation efficiency discussed here should exist not only in logic-circuit layer, but also in both path layer and medium layer. A theoretical method of the measurement of layers and comprehensive evaluations is presented based on the concept of transmission efficiency.
A Historical Analysis of Academic Development Using the Theoretical Lens of Pierre Bourdieu
Kloot, Bruce Charles
2015-01-01
This paper provides a history of academic development by examining how a South African institution coped with the potent social forces confronting it before the collapse of apartheid. Theoretically, it draws on the framework of Pierre Bourdieu and engages with a paper written a decade ago by Naidoo, who also used Bourdieu to understand…
Energy Technology Data Exchange (ETDEWEB)
Kim, Jeong Ah; Kim, Mi Hye; Lee, Mi Kyung; Oh, Ki Keun [College of Medicine, Yonsei University, Seoul (Korea, Republic of); Kim, Eun Kyung [Pundang CHA General Hospital, College of Medicine, Pochon CHA University, Seoul (Korea, Republic of)
2000-05-01
To analyze the mammographic findings of extensive intraductal component (EIC)-positive early invasive breast carcinoma and to determine the mammographic features which predict an EIC positivity in an invasive carcinoma. The mammographic and pathologic findings in 71 patients aged 34-79 (mean 50) years in whom stage I or II invasive breast carcinoma had been diagnosed were retrospectively analysed. The mammographic findings were assigned to one of three groups: mass, mass with microcalcification, or microcalcification only. The shape and distribution of a calcification were classified according to the BI-RADS lexicon, and its extent was classified as either more or less than 3 cm. To detect the presence or absence of EIC and the type of ductal carcinoma in situ (DCIS), the findings were re-examined by means of slide mappings. Twenty-eight of 71 patients (39%) showed ECI positivity. The mammographic findings of EIC-positive invasive cancer (n=3D28) were mass with microcalcification (n=3D14), microcalcification only (n=3D7) and mass only (n=3D7). The mammographic finding which predicted EIC positivity was mass with microcalcification (PPV:0.67, NPV:0.33, p=3D0.02). A mammographic of mass only (n=3D39) showed a significantly high negative predictive value for EIC positivity. (PPV 0.18, NPV 0.82, P less than 0.01). A comparison of cases with or without calcification showed that those with microcalcifications (n=3D32) showed a significantly high PPV of 0.66 (NPV:0.34, p less than 0.01) while those without calcification (n=3D39) showed a significantly high NPV of 0.82 (PPV:0.18, p less than 0.01). There were no significant differences in positive predictive values for EIC between the shape, distribution and extent of calcifications. Whenever microcalcification with or without mass is seen on mammographs obtained during early breast cancer, we can predict EIC-positivity, regardless of shape or distribution according to the BI-RADS lexicon. (author)
Genomic analysis reveals extensive gene duplication within the bovine TRB locus
Directory of Open Access Journals (Sweden)
Law Andy
2009-04-01
Full Text Available Abstract Background Diverse TR and IG repertoires are generated by V(DJ somatic recombination. Genomic studies have been pivotal in cataloguing the V, D, J and C genes present in the various TR/IG loci and describing how duplication events have expanded the number of these genes. Such studies have also provided insights into the evolution of these loci and the complex mechanisms that regulate TR/IG expression. In this study we analyze the sequence of the third bovine genome assembly to characterize the germline repertoire of bovine TRB genes and compare the organization, evolution and regulatory structure of the bovine TRB locus with that of humans and mice. Results The TRB locus in the third bovine genome assembly is distributed over 5 scaffolds, extending to ~730 Kb. The available sequence contains 134 TRBV genes, assigned to 24 subgroups, and 3 clusters of DJC genes, each comprising a single TRBD gene, 5–7 TRBJ genes and a single TRBC gene. Seventy-nine of the TRBV genes are predicted to be functional. Comparison with the human and murine TRB loci shows that the gene order, as well as the sequences of non-coding elements that regulate TRB expression, are highly conserved in the bovine. Dot-plot analyses demonstrate that expansion of the genomic TRBV repertoire has occurred via a complex and extensive series of duplications, predominantly involving DNA blocks containing multiple genes. These duplication events have resulted in massive expansion of several TRBV subgroups, most notably TRBV6, 9 and 21 which contain 40, 35 and 16 members respectively. Similarly, duplication has lead to the generation of a third DJC cluster. Analyses of cDNA data confirms the diversity of the TRBV genes and, in addition, identifies a substantial number of TRBV genes, predominantly from the larger subgroups, which are still absent from the genome assembly. The observed gene duplication within the bovine TRB locus has created a repertoire of phylogenetically
TAPPS Release 1: Plugin-Extensible Platform for Technical Analysis and Applied Statistics
Directory of Open Access Journals (Sweden)
Justin Sam Chew
2016-01-01
Full Text Available We present the first release of TAPPS (Technical Analysis and Applied Statistics System; a Python implementation of a thin software platform aimed towards technical analyses and applied statistics. The core of TAPPS is a container for 2-dimensional data frame objects and a TAPPS command language. TAPPS language is not meant to be a programming language for script and plugin development but for the operational purposes. In this aspect, TAPPS language takes on the flavor of SQL rather than R, resulting in a shallower learning curve. All analytical functions are implemented as plugins. This results in a defined plugin system, which enables rapid development and incorporation of analysis functions. TAPPS Release 1 is released under GNU General Public License 3 for academic and non-commercial use. TAPPS code repository can be found at http://github.com/mauriceling/tapps.
Theoretical and Experimental Spectroscopic Analysis of Cyano-Substituted Styrylpyridine Compounds
Directory of Open Access Journals (Sweden)
Jorge Lopez-Cruz
2013-02-01
Full Text Available A combined theoretical and experimental study on the structure, infrared, UV-Vis and 1H NMR data of trans-2-(m-cyanostyrylpyridine, trans-2-[3-methyl-(m-cyanostyryl]pyridine and trans-4-(m-cyanostyrylpyridine is presented. The synthesis was carried out with an efficient Knoevenagel condensation using green chemistry conditions. Theoretical geometry optimizations and their IR spectra were carried out using the Density Functional Theory (DFT in both gas and solution phases. For theoretical UV-Vis and 1H NMR spectra, the Time-Dependent DFT (TD-DFT and the Gauge-Including Atomic Orbital (GIAO methods were used, respectively. The theoretical characterization matched the experimental measurements, showing a good correlation. The effect of cyano- and methyl- substituents, as well as of the N-atom position in the pyridine ring on the UV-Vis, IR and NMR spectra, was evaluated. The UV-Vis results showed no significant effect due to electron-withdrawing cyano- and electron-donating methyl-substituents. The N-atom position, however, caused a slight change in the maximum absorption wavelengths. The IR normal modes were assigned for the cyano- and methyl-groups. 1H NMR spectra showed the typical doublet signals due to protons in the trans position of a double bond. The theoretical characterization was visibly useful to assign accurately the signals in IR and 1H NMR spectra, as well as to identify the most probable conformation that could be present in the formation of the styrylpyridine-like compounds.
Theoretical and experimental spectroscopic analysis of cyano-substituted styrylpyridine compounds.
Castro, Maria Eugenia; Percino, Maria Judith; Chapela, Victor M; Ceron, Margarita; Soriano-Moro, Guillermo; Lopez-Cruz, Jorge; Melendez, Francisco J
2013-02-18
A combined theoretical and experimental study on the structure, infrared, UV-Vis and 1H NMR data of trans-2-(m-cyanostyryl)pyridine, trans-2-[3-methyl-(m-cyanostyryl)]pyridine and trans-4-(m-cyanostyryl)pyridine is presented. The synthesis was carried out with an efficient Knoevenagel condensation using green chemistry conditions. Theoretical geometry optimizations and their IR spectra were carried out using the Density Functional Theory (DFT) in both gas and solution phases. For theoretical UV-Vis and 1H NMR spectra, the Time-Dependent DFT (TD-DFT) and the Gauge-Including Atomic Orbital (GIAO) methods were used, respectively. The theoretical characterization matched the experimental measurements, showing a good correlation. The effect of cyano- and methyl- substituents, as well as of the N-atom position in the pyridine ring on the UV-Vis, IR and NMR spectra, was evaluated. The UV-Vis results showed no significant effect due to electron-withdrawing cyano- and electron-donating methyl-substituents. The N-atom position, however, caused a slight change in the maximum absorption wavelengths. The IR normal modes were assigned for the cyano- and methyl-groups. 1H NMR spectra showed the typical doublet signals due to protons in the trans position of a double bond. The theoretical characterization was visibly useful to assign accurately the signals in IR and 1H NMR spectra, as well as to identify the most probable conformation that could be present in the formation of the styrylpyridine-like compounds.
Theoretical and Experimental Spectroscopic Analysis of Cyano-Substituted Styrylpyridine Compounds
Castro, Maria Eugenia; Percino, Maria Judith; Chapela, Victor M.; Ceron, Margarita; Soriano-Moro, Guillermo; Lopez-Cruz, Jorge; Melendez, Francisco J.
2013-01-01
A combined theoretical and experimental study on the structure, infrared, UV-Vis and 1H NMR data of trans-2-(m-cyanostyryl)pyridine, trans-2-[3-methyl-(m-cyanostyryl)] pyridine and trans-4-(m-cyanostyryl)pyridine is presented. The synthesis was carried out with an efficient Knoevenagel condensation using green chemistry conditions. Theoretical geometry optimizations and their IR spectra were carried out using the Density Functional Theory (DFT) in both gas and solution phases. For theoretical UV-Vis and 1H NMR spectra, the Time-Dependent DFT (TD-DFT) and the Gauge-Including Atomic Orbital (GIAO) methods were used, respectively. The theoretical characterization matched the experimental measurements, showing a good correlation. The effect of cyano- and methyl-substituents, as well as of the N-atom position in the pyridine ring on the UV-Vis, IR and NMR spectra, was evaluated. The UV-Vis results showed no significant effect due to electron-withdrawing cyano- and electron-donating methyl-substituents. The N-atom position, however, caused a slight change in the maximum absorption wavelengths. The IR normal modes were assigned for the cyano- and methyl-groups. 1H NMR spectra showed the typical doublet signals due to protons in the trans position of a double bond. The theoretical characterization was visibly useful to assign accurately the signals in IR and 1H NMR spectra, as well as to identify the most probable conformation that could be present in the formation of the styrylpyridine-like compounds. PMID:23429190
Phylogenomic Analysis Reveals Extensive Phylogenetic Mosaicism in the Human GPCR Superfamily
Directory of Open Access Journals (Sweden)
Mathew Woodwark
2007-01-01
Full Text Available A novel high throughput phylogenomic analysis (HTP was applied to the rhodopsin G-protein coupled receptor (GPCR family. Instances of phylogenetic mosaicism between receptors were found to be frequent, often as instances of correlated mosaicism and repeated mosaicism. A null data set was constructed with the same phylogenetic topology as the rhodopsin GPCRs. Comparison of the two data sets revealed that mosaicism was found in GPCRs in a higher frequency than would be expected by homoplasy or the effects of topology alone. Various evolutionary models of differential conservation, recombination and homoplasy are explored which could result in the patterns observed in this analysis. We find that the results are most consistent with frequent recombination events. A complex evolutionary history is illustrated in which it is likely frequent recombination has endowed GPCRs with new functions. The pattern of mosaicism is shown to be informative for functional prediction for orphan receptors. HTP analysis is complementary to conventional phylogenomic analyses revealing mosaicism that would not otherwise have been detectable through conventional phylogenetics.
Thieler, E. Robert; Himmelstoss, Emily A.; Zichichi, Jessica L.; Ergul, Ayhan
2009-01-01
The Digital Shoreline Analysis System (DSAS) version 4.0 is a software extension to ESRI ArcGIS v.9.2 and above that enables a user to calculate shoreline rate-of-change statistics from multiple historic shoreline positions. A user-friendly interface of simple buttons and menus guides the user through the major steps of shoreline change analysis. Components of the extension and user guide include (1) instruction on the proper way to define a reference baseline for measurements, (2) automated and manual generation of measurement transects and metadata based on user-specified parameters, and (3) output of calculated rates of shoreline change and other statistical information. DSAS computes shoreline rates of change using four different methods: (1) endpoint rate, (2) simple linear regression, (3) weighted linear regression, and (4) least median of squares. The standard error, correlation coefficient, and confidence interval are also computed for the simple and weighted linear-regression methods. The results of all rate calculations are output to a table that can be linked to the transect file by a common attribute field. DSAS is intended to facilitate the shoreline change-calculation process and to provide rate-of-change information and the statistical data necessary to establish the reliability of the calculated results. The software is also suitable for any generic application that calculates positional change over time, such as assessing rates of change of glacier limits in sequential aerial photos, river edge boundaries, land-cover changes, and so on.
Totten, Sarah M; Feasley, Christa L; Bermudez, Abel; Pitteri, Sharon J
2017-03-03
Protein glycosylation is of increasing interest due to its important roles in protein function and aberrant expression with disease. Characterizing protein glycosylation remains analytically challenging due to its low abundance, ion suppression issues, and microheterogeneity at glycosylation sites, especially in complex samples such as human plasma. In this study, the utility of three common N-linked glycopeptide enrichment techniques is compared using human plasma. By analysis on an LTQ-Orbitrap Elite mass spectrometer, electrostatic repulsion hydrophilic interaction liquid chromatography using strong anion exchange solid-phase extraction (SAX-ERLIC) provided the most extensive N-linked glycopeptide enrichment when compared with multilectin affinity chromatography (M-LAC) and Sepharose-HILIC enrichments. SAX-ERLIC enrichment yielded 191 unique glycoforms across 72 glycosylation sites from 48 glycoproteins, which is more than double that detected using other enrichment techniques. The greatest glycoform diversity was observed in SAX-ERLIC enrichment, with no apparent bias toward specific glycan types. SAX-ERLIC enrichments were additionally analyzed by an Orbitrap Fusion Lumos mass spectrometer to maximize glycopeptide identifications for a more comprehensive assessment of protein glycosylation. In these experiments, 829 unique glycoforms were identified across 208 glycosylation sites from 95 plasma glycoproteins, a significant improvement from the initial method comparison and one of the most extensive site-specific glycosylation analysis in immunodepleted human plasma to date. Data are available via ProteomeXchange with identifier PXD005655.
面向对象技术的可拓分析%Extension Analysis for Object-oriented Programming Technology
Institute of Scientific and Technical Information of China (English)
刘汉龙
2001-01-01
This article introduces the extension analysis for theobject-oriented programming technology, discusses the object matter-element's “multi-value",and presents the transformation conditions of the object matter-element and the rules of decomposition and combination.The compatible and non-comaptible problem in computer development is considered by man-machine interface's DVI. At the same time,the concept of “replace prices” is presented.Taking the word processing software for example,extension analysis used in the optimization of object-oriented programming works well.%在计算机面向对象技术中引入可拓分析，探讨了作为对象物元的“多重价值”，提出了这种对象物元的变换条件、对象物元分解和组合的规则，并从人机接口中的DVI来透视计算机发展中“相容与不相容问题”，同时给出了“替代价格”的概念，以字处理软件为例进行分析，说明可拓分析用于面向对象程序设计的优化能产生良好的效果.
Thieler, E. Robert; Himmelstoss, Emily A.; Zichichi, Jessica L.; Ergul, Ayhan
2009-01-01
The Digital Shoreline Analysis System (DSAS) version 4.0 is a software extension to ESRI ArcGIS v.9.2 and above that enables a user to calculate shoreline rate-of-change statistics from multiple historic shoreline positions. A user-friendly interface of simple buttons and menus guides the user through the major steps of shoreline change analysis. Components of the extension and user guide include (1) instruction on the proper way to define a reference baseline for measurements, (2) automated and manual generation of measurement transects and metadata based on user-specified parameters, and (3) output of calculated rates of shoreline change and other statistical information. DSAS computes shoreline rates of change using four different methods: (1) endpoint rate, (2) simple linear regression, (3) weighted linear regression, and (4) least median of squares. The standard error, correlation coefficient, and confidence interval are also computed for the simple and weighted linear-regression methods. The results of all rate calculations are output to a table that can be linked to the transect file by a common attribute field. DSAS is intended to facilitate the shoreline change-calculation process and to provide rate-of-change information and the statistical data necessary to establish the reliability of the calculated results. The software is also suitable for any generic application that calculates positional change over time, such as assessing rates of change of glacier limits in sequential aerial photos, river edge boundaries, land-cover changes, and so on.
Institute of Scientific and Technical Information of China (English)
DONG Wu-qin; JIA Zhen-hong
2008-01-01
The relation between the power of the Brillouin signal and the swain is one of the bases of the distributed fiber sensors of temperature and strain. The coefficient of the Brillouin gain can be changed by the temperature and the strain that will affect the power of the Brillouin scattering. The relation between the change of the Brillouin gain coefficient and the strain is thought to be linear by many researchers. However, it is not always linear based on the theoretical analysis and numerical simulation. Therefore, errors will be caused if the relation between the change of the Brillouin gain coefficient and the strain is regarded as to be linear approximately for measuring the temperature and the strain. For this reason, the influence of thep arameters on the Brillouin gain coefficient is proposed through theoretical analysis and numerical simulation.
Theoretical analysis of the S{sub 2}←S{sub 0} vibronic spectrum of the 2-pyridone dimer
Energy Technology Data Exchange (ETDEWEB)
Kopec, Sabine; Köppel, Horst [Theoretische Chemie, Physikalisch-Chemisches Institut, Universität Heidelberg, Im Neuenheimer Feld 229, D-69120 Heidelberg (Germany)
2016-01-14
The interplay between excitonic and vibronic coupling in hydrogen-bonded molecular dimers leads to complex spectral structures and other intriguing phenomena such as a quenching of the excitonic energy splitting. We recently extended our analysis from that of the quenching mechanism to the theoretical investigation of the complete vibronic spectrum for the ortho-cyanophenol dimer. We now apply the same approach to the vibronic spectrum of the 2-pyridone dimer and discuss the assignment of vibronic lines to gain insight into the underlying coupling mechanism. This is based on potential energy surfaces obtained at the RI-CC2/aug-cc-pVTZ level. They are used for the dynamical analysis in the framework of a multi-mode vibronic coupling approach. The theoretical results based on the quadratic vibronic coupling model are found to be in good agreement with the experimental resonant two-photon ionization spectrum.
DEFF Research Database (Denmark)
Diky, Vladimir; Chirico, Robert D.; Muzny, Chris
property values and expert system for data analysis and generation of recommended property values at the specified conditions along with uncertainties on demand. The most recent extension of TDE covers solvent design and multi-component process stream property calculations with uncertainty analysis......ThermoData Engine (TDE, NIST Standard Reference Databases 103a and 103b) is the first product that implements the concept of Dynamic Data Evaluation in the fields of thermophysics and thermochemistry, which includes maintaining the comprehensive and up-to-date database of experimentally measured....... Solvent Design function serves three tasks: (1) selection of best solvent for a solid solute, (2) search for a selective solvent for a solid binary mixture, and (3) selection of best solvent for extraction. Solvents are selected from the list of registered compounds encountering more than 27,000 entries...
DEFF Research Database (Denmark)
Diky, Vladimir; Chirico, Robert D.; Muzny, Chris
ThermoData Engine (TDE, NIST Standard Reference Databases 103a and 103b) is the first product that implements the concept of Dynamic Data Evaluation in the fields of thermophysics and thermochemistry, which includes maintaining the comprehensive and up-to-date database of experimentally measured...... property values and expert system for data analysis and generation of recommended property values at the specified conditions along with uncertainties on demand. The most recent extension of TDE covers solvent design and multi-component process stream property calculations with uncertainty analysis....... Selection is made by best efficiency (depending on the task, solubility, selectivity, or distribution coefficient, etc.) and matching other requirements requested by the user. At user’s request, efficiency criteria are evaluated based on experimental data for binary mixtures or predictive models (UNIFAC...
The integrated microbial genomes (IMG) system in 2007: datacontent and analysis tool extensions
Energy Technology Data Exchange (ETDEWEB)
Markowitz, Victor M.; Szeto, Ernest; Palaniappan, Krishna; Grechkin, Yuri; Chu, Ken; Chen, I-Min A.; Dubchak, Inna; Anderson, Iain; Lykidis, Athanasios; Mavromatis, Konstantinos; Ivanova, Natalia N.; Kyrpides, Nikos C.
2007-08-01
The Integrated Microbial Genomes (IMG) system is a data management, analysis and annotation platform for all publicly available genomes. IMG contains both draft and complete JGI microbial genomes integrated with all other publicly available genomes from all three domains of life, together with a large number of plasmids and viruses. IMG provides tools and viewers for analyzing and annotating genomes, genes and functions, individually or in a comparative context. Since its first release in 2005, IMG's data content and analytical capabilities have been constantly expanded through quarterly releases. IMG is provided by the DOE-Joint Genome Institute (JGI) and is available from http://img.jgi.doe.gov.
Sjogren, D.; Martin, Y. E.; Jagielko, L.
2010-12-01
Gimbarzevsky (1988) collected an exceptional landsliding inventory for the Haida Gwaii, British Columbia (formerly called the Queen Charlotte Islands). This data base includes more than 8 000 landsliding vectors, with an areal coverage of about 10 000 km2. Unfortunately, this landsliding inventory was never published in the referred literature, despite its regional significance. The data collection occurred prior to widespread use of GIS technologies in landsliding analysis, thus restricting the types of analyses that were undertaken at the time relative to what is possible today. Gimbarzevsky identified the landsliding events from 1:50 000 aerial photographs, and then transferred the landslide vectors to NTS map sheets. In this study, we digitized the landslide vectors from these original map sheets and connected each vector to a digital elevation model. Lengths of landslide vectors were then compared to results of Rood (1984), whose landsliding inventory for the Haida Gwaii relied on larger-scale aerial photographs (~ 1:13 000). A comparison of the two data bases shows that Rood’s inventory contains a more complete record of smaller landslides, whereas Gimbarzevsky’s inventory provides a much better statistical representation of less frequently occurring, medium to large landslide events. We then apply discriminant analysis to the Gimbarzevsky data base to assess which of a set of ten predictor variables, selected on the basis of mechanical theory, best predict failed vs. unfailed locations in the landscape (referred to as the grouping variable in discriminant analysis). Certain predictor variables may be cross-correlated, and any one particular variable may be related to several aspects of mechanical theory (for example, a particular variable may affect various components of shear stress and/or shear strength); it is important to recognize that the significance of particular groupings may reflect this information. Eight of the original variables were found
Metabolomics as an extension of proteomic analysis: study of acute kidney injury.
Portilla, Didier; Schnackenberg, Laura; Beger, Richard D
2007-11-01
Although proteomics studies the global expression of proteins, metabolomics characterizes and quantifies their end products: the metabolites, produced by an organism under a certain set of conditions. From this perspective it is apparent that proteomics and metabolomics are complementary and when joined allow a fuller appreciation of an organism's phenotype. Our studies using (1)H-nuclear magnetic resonance spectroscopic analysis showed the presence of glucose, amino acids, and trichloroacetic acid cycle metabolites in the urine after 48 hours of cisplatin administration. These metabolic alterations precede changes in serum creatinine. Biochemical studies confirmed the presence of glucosuria, but also showed the accumulation of nonesterified fatty acids, and triglycerides in serum, urine, and kidney tissue, despite increased levels of plasma insulin. These metabolic alterations were ameliorated by the use of fibrates. We propose that the injury-induced metabolic profile may be used as a biomarker of cisplatin-induced nephrotoxicity. These studies serve to illustrate that metabolomic studies add insight into pathophysiology not provided by proteomic analysis alone.
Kayser, Manfred; Krawczak, Michael; Excoffier, Laurent; Dieltjes, Patrick; Corach, Daniel; Pascali, Vincente; Gehrig, Christian; Bernini, Luigi F.; Jespersen, Jørgen; Bakker, Egbert; Roewer, Lutz; de Knijff, Peter
2001-01-01
The genetic variance at seven Y-chromosomal microsatellite loci (or short tandem repeats [STRs]) was studied among 986 male individuals from 20 globally dispersed human populations. A total of 598 different haplotypes were observed, of which 437 (73.1%) were each found in a single male only. Population-specific haplotype-diversity values were .86–.99. Analyses of haplotype diversity and population-specific haplotypes revealed marked population-structure differences between more-isolated indigenous populations (e.g., Central African Pygmies or Greenland Inuit) and more-admixed populations (e.g., Europeans or Surinamese). Furthermore, male individuals from isolated indigenous populations shared haplotypes mainly with male individuals from their own population. By analysis of molecular variance, we found that 76.8% of the total genetic variance present among these male individuals could be attributed to genetic differences between male individuals who were members of the same population. Haplotype sharing between populations, ΦST statistics, and phylogenetic analysis identified close genetic affinities among European populations and among New Guinean populations. Our data illustrate that Y-chromosomal STR haplotypes are an ideal tool for the study of the genetic affinities between groups of male subjects and for detection of population structure. PMID:11254455
Institute of Scientific and Technical Information of China (English)
Zilun Chen; Jing Hou; Zongfu Jiang
2007-01-01
A theoretical analysis of the pump-induced temperature change and associated thermal phase shift occurring in a fiber laser is presented. The temperature rise and thermal phase shift from the moment when pump is turned on to steady-state in fiber lasers, such as Yb-doped fiber laser, are numerical calculated.With the same parameters, the numerical solution is in good agreement with the finite-element (ANSYS software) simulation.
Shujun Yu; Xiangxue Wang; Rui Zhang; Tongtong Yang; Yuejie Ai; Tao Wen; Wei Huang; Tasawar Hayat; Ahmed Alsaedi; Xiangke Wang
2017-01-01
Although graphene oxide (GO) has been used in multidisciplinary areas due to its excellent physicochemical properties, its environmental behavior and fate are still largely unclear. In this study, batch experiments, spectroscopy analysis and theoretical calculations were addressed to promote a more comprehensive understanding toward the coagulation behavior of GO onto TiO2 under various environmental conditions (pH, co-existing ions, temperature, etc.). The results indicated that neutral pH w...
Pugachev, A. O.;Deckner, M.;Kwanka, K.;Helm, P.;Schettel, J.
2017-01-01
This paper presents an analysis of the experimental and theoretical methods used to study rotordynamic characteristics of short staggered labyrinth gas seal. Two experimental identification procedures referred to as static and dynamic methods are presented. The static method allows determining direct and cross-coupled stiffness coefficients of the seal by integrating measured circumferential pressure distribution in cavities at various shaft eccentric positions. In the dynamic method, identif...
Boeck, Robert; Chrostowski, Lukas; Jaeger, Nicolas A. F.
2014-09-01
Vernier racetrack resonators offer advantages over single racetrack resonators such as extending the free spectral range (FSR).1-3 Here, we have presented a theoretical sensitivity analysis on quadruple Vernier racetrack resonators based on varying, one at a time, various fabrication dependent parameters. These parameters include the waveguide widths, heights, and propagation losses. We have shown that it should be possible to design a device that meets typical commercial specifications while being tolerant to changes in these parameters.
Institute of Scientific and Technical Information of China (English)
符建; 何赛灵; 肖三水; 仇霪; 何建军
2001-01-01
A theoretical analysis is presented for a channel drop tunnelling structure composed of a horizontal input channel, a vertical output channel and a multi-mode cavity in a photonic crystal. Criteria for a complete transfer are derived for applications of wavelength division demultiplexing. The analytical results are verified with a numerical simulation using a finite difference time domain method. The vertical channel dropping tunnelling system makes the demultiplexing device much more compact, as compared to the conventional parallel channel dropping system.
Theoretical Mechanics Theoretical Physics 1
Dreizler, Reiner M
2011-01-01
After an introduction to basic concepts of mechanics more advanced topics build the major part of this book. Interspersed is a discussion of selected problems of motion. This is followed by a concise treatment of the Lagrangian and the Hamiltonian formulation of mechanics, as well as a brief excursion on chaotic motion. The last chapter deals with applications of the Lagrangian formulation to specific systems (coupled oscillators, rotating coordinate systems, rigid bodies). The level of this textbook is advanced undergraduate. The authors combine teaching experience of more than 40 years in all fields of Theoretical Physics and related mathematical disciplines and thorough knowledge in creating advanced eLearning content. The text is accompanied by an extensive collection of online material, in which the possibilities of the electronic medium are fully exploited, e.g. in the form of applets, 2D- and 3D-animations. - A collection of 74 problems with detailed step-by-step guidance towards the solutions. - A col...
Directory of Open Access Journals (Sweden)
Toshiaki Natsuki
2017-08-01
Full Text Available This paper reviews the recent research of carbon nanotubes (CNTs used as nanomechanical sensing elements based mainly on theoretical models. CNTs have demonstrated considerable potential as nanomechanical mass sensor and atomic force microscope (AFM tips. The mechanical and vibrational characteristics of CNTs are introduced to the readers. The effects of main parameters of CNTs, such as dimensions, layer number, and boundary conditions on the performance characteristics are investigated and discussed. It is hoped that this review provides knowledge on the application of CNTs as nanomechanical sensors and computational methods for predicting their properties. Their theoretical studies based on the mechanical properties such as buckling strength and vibration frequency would give a useful reference for designing CNTs as nanomechanical mass sensor and AFM probes.
Experimental-theoretical analysis of laminar internal forced convection with nanofluids
Energy Technology Data Exchange (ETDEWEB)
Cerqueira, Ivana G.; Cotta, Renato M. [Lab. of Transmission and Technology of Heat-LTTC. Mechanical Eng. Dept. - POLI and COPPE/UFRJ, Rio de Janeiro, RJ (Brazil)], E-mail: cotta@mecanica.coppe.ufrj.br; Mota, Carlos Alberto A. [Conselho Nacional de Pesquisas - CNPq, Brasilia, DF (Brazil)], e-mail: carlosal@cnpq.br; Nunes, Jeziel S. [INPI, Rio de Janeiro, RJ (Brazil)], e-mail: jeziel@inpi.gov.br
2010-07-01
This work reports fundamental experimental-theoretical research related to heat transfer enhancement in laminar channel flow with nanofluids, which are essentially modifications of the base fluid with the dispersion of metal oxide nanoparticles. The theoretical work was performed by making use of mixed symbolic-numerical computation (Mathematica 7.0 platform) and a hybrid numerical-analytical methodology (Generalized Integral Transform Technique - GITT) in accurately handling the governing partial differential equations for the heat and fluid flow problem formulation with temperature dependency in all the thermophysical properties. Experimental work was also undertaken based on a thermohydraulic circuit built for this purpose, and sample results are presented to verify the proposed model. The aim is to illustrate detailed modeling and robust simulation attempting to reach an explanation of the controversial heat transfer enhancement observed in laminar forced convection with nanofluids. (author)
Directory of Open Access Journals (Sweden)
Carren Pindiriri
2014-12-01
Full Text Available A number of empirical studies have been carried out to assess the impact of sustainable development assistance (SDA and aid on environmental quality in poor countries, but these studies have been characterized by weak theoretical anchor. It is against this background that this paper provides a theoretical basis from which empirical models of the effectiveness and impact of SDA on environmental quality can be derived. The paper applies the classical consumer theory of utility maximization, Keynesian macroeconomic model and further suggests an incentive-based approach (post-cure financial SDA model in explaining the effectiveness of environmental financing. The theories discussed in this paper confirm the results obtained by previous empirical studies on environmental financing.
Institute of Scientific and Technical Information of China (English)
无
2007-01-01
A novel cooperative diversity scheme based on Distributed Space-Time Block Coding and Multi-Carrier Code Division Multiple Access (DSTBC-MC-CDMA) is proposed which works well in frequency selective fading channels with multiple single-antenna users. And an analytical error model is established to describe the symbol decoding errors between interusers, based on which a close form expression for theoretical Bit Error Rate (BER) performance of the scheme is derived to analyze the influence of the interuser decoding errors on the BER performance of the scheme. Then simulation is complimented to verify the analytic result above, which also shows that the BER performance of DSTBC-MC-CDMA outgoes that of non-cooperative MC-CDMA with considerable gains. Furthermore, the simulations coincide with the theoretical results well.
Analysis of theoretical and real values of heat consumption in units of the apartment building
Pavloková, Petra; Richter, Aleš; Janša, Jan
2016-06-01
This article is focused on heat consumption in the apartment building and the factors affecting it. The apartment building has three entrances and four over ground floors and one underground floor. In the entire apartment building there are 24 flats, which they are identical (kitchen, bedroom, living room and bathroom). In flats on radiators were installed the ratio heat meters according to Act 318/2012 Coll. by the Metrology Act. The ratio heat meters are used for fair billing of the heat costs for all owners. Continuous monitoring of the actual heat consumption in the flats were collected data of the real heat consumption. The theoretical values of heat consumption were counted in software ENERGIE. The apartment building is divided into24 flats and the calculation was made for each of them. The theoretical and real heat consumption was compared.
Kong, Lingzhu; Cooper, Valentino R.; Nijem, Nour; Li, Kunhao; Li, Jing; Chabal, Yves J.; Langreth, David C.
2009-02-01
Hydrogen adsorption by the metal-organic framework (MOF) structure Zn2(BDC)2(TED) is investigated using a combination of experimental and theoretical methods. By using the nonempirical van der Waals density-functional approach, it is found that the locus of deepest H2 binding positions lies within two types of narrow channel. The energies of the most stable binding sites, as well as the number of such binding sites, are consistent with the values obtained from experimental adsorption isotherms and heat of adsorption data. Calculations of the shift of the H-H stretch frequency when adsorbed in the MOF give a value of approximately -30cm-1 at the strongest binding point in each of the two channels. Ambient temperature infrared-absorption spectroscopy measurements give a hydrogen peak centered at 4120cm-1 , implying a shift consistent with the theoretical calculations.
Sendi, Pedram; Al, Maiwenn J; Gafni, Amiram; Birch, Stephen
2004-05-01
Bridges and Terris (Soc. Sci. Med. (2004)) critique our paper on the alternative decision rule of economic evaluation in the presence of uncertainty and constrained resources within the context of a portfolio of health care programs (Sendi et al. Soc. Sci. Med. 57 (2003) 2207). They argue that by not adopting a formal portfolio theory approach we overlook the optimal solution. We show that these arguments stem from a fundamental misunderstanding of the alternative decision rule of economic evaluation. In particular, the portfolio theory approach advocated by Bridges and Terris is based on the same theoretical assumptions that the alternative decision rule set out to relax. Moreover, Bridges and Terris acknowledge that the proposed portfolio theory approach may not identify the optimal solution to resource allocation problems. Hence, it provides neither theoretical nor practical improvements to the proposed alternative decision rule.
Pavlík, Zbyšek; Fiala, Lukáš; Jerman, Miloš; Vejmelková, Eva; Pavlíková, Milena; Keppert, Martin; Černý, Robert
2014-10-01
The moisture-dependent thermal conductivity of two types of lightweight ceramic brick body is analyzed using both theoretical and experimental approaches. The basic physical properties are determined at first. Then, an impulse method is applied for the thermal-conductivity measurement. Initially, the material samples are dried, after that, they are exposed to liquid water for specific time intervals, and finally the moisture content is allowed to homogenize within the whole volume. The thermal-conductivity measurement is performed for different moisture contents achieved in this way. In the theoretical part, the homogenization principles are used for the calculation of the moisture-dependent thermal conductivity, utilizing the distribution functions based on the pore-size distribution measurement. Finally, a comparison of the measured and calculated data is done, and the validity of the applied effective media treatment is assessed.
Konik, Robert M.; Sfeir, Matthew Y.; Misewich, James A.
2015-02-01
We demonstrate that a nonperturbative framework for the treatment of the excitations of single-walled carbon nanotubes based upon a field theoretic reduction is able to accurately describe experiment observations of the absolute values of excitonic energies. This theoretical framework yields a simple scaling function from which the excitonic energies can be read off. This scaling function is primarily determined by a single parameter, the charge Luttinger parameter of the tube, which is in turn a function of the tube chirality, dielectric environment, and the tube's dimensions, thus expressing disparate influences on the excitonic energies in a unified fashion. We test this theory explicitly on the data reported by Dukovic et al. [Nano Lett. 5, 2314 (2005), 10.1021/nl0518122] and Sfeir et al. [Phys. Rev. B 82, 195424 (2010), 10.1103/PhysRevB.82.195424] and so demonstrate the method works over a wide range of reported excitonic spectra.
Institute of Scientific and Technical Information of China (English)
徐铜文; 杨伟华; 何炳林
1999-01-01
The models were established for the theoretical current-voltage characteristics in water dissociation process on a bipolar membrane. Particular attention was given to the transport of the water ions and electrolyte ions as well as the membrane physical structure and configuration. The factors on the water splitting process were adequately analysed based on the derived theoretical current-voltage characteristics and several good suggestions were proposed for decreasing the work voltage in practical operations. In addition, the model can give a reasonable explanation for the catalytic effect of some chemicals, such as amphiprotic hydroxide compounds, weak polymeric acids and bases, etc. It is shown that the catalyst may be responsible for the increase in dissociation rate constant of water and therefore enhance the water dissociation. The guidelines for choosing a proper catalyst were also proposed.
Analysis and Extension of the PCA Method, Estimating a Noise Curve from a Single Image
Directory of Open Access Journals (Sweden)
Miguel Colom
2016-12-01
Full Text Available In the article 'Image Noise Level Estimation by Principal Component Analysis', S. Pyatykh, J. Hesser, and L. Zheng propose a new method to estimate the variance of the noise in an image from the eigenvalues of the covariance matrix of the overlapping blocks of the noisy image. Instead of using all the patches of the noisy image, the authors propose an iterative strategy to adaptively choose the optimal set containing the patches with lowest variance. Although the method measures uniform Gaussian noise, it can be easily adapted to deal with signal-dependent noise, which is realistic with the Poisson noise model obtained by a CMOS or CCD device in a digital camera.
Eplényi Anna; Oláh-Christian Brigitta
2015-01-01
This paper endeavours to highlight three aspects of postmodern landscape design: theoretical basis, composition and design elements. Postmodern theories, philosophy influenced the language of the postmodern landscape architecture and got materialized in the use of narratives, eclecticism, the Rhizome-principle. Postmodern landscape composition can be associated with anti-hierarchy, unusual structures, landforms, and playful moods. Postmodern design elements consist of the strong graphical use...
Directory of Open Access Journals (Sweden)
L.Yu. Sager
2011-01-01
Full Text Available The article is devoted to the use of communications in terms of management of information and interpersonal interaction in the domestic enterprise level. in the article the basic theoretical aspects of internal communications in the enterprise management system as part of its efficient functioning: clarified the essence of the concept of "communication"; systematized the advantages and disadvantages of internal communications of the enterprises, and their goals on the enterprise; systematized the barriers to effective communication process.
Experimental Evidence and Theoretical Analysis of Nanobubble Stability Within Graphene Nanoscrolls.
Mokkapati, V R S S; Ozguz, Volkan; Kosar, Ali
2016-06-01
In this study direct observation and dynamics of nanoscale water and nanobubbles within graphene nanoscrolls were reported. The life time of these nanobubbles is much higher than expected, which we propose is due to the combination of several factors including localized heating and surface charge. The stability of the nanobubbles within graphene nanoscrolls has been theoretically analyzed. The nanobubbles inside these nanoscrolls reveal a wide distribution of graphene-water contact angles. Bubble dynamics within these graphene nanochannels was directly observed and recorded.
Dias, Natália Martins; Gomes,Cristiano Mauro Assis; Reppold, Caroline Tozzi; Fioravanti-Bastos, Ana Carolina; Pires,Emmy Uehara; Carreiro, Luiz Renato Rodrigues; SEABRA,Alessandra Gotuzo
2015-01-01
Despite relative consensus on the existence of three basic executive functions (EF) (inhibition, working memory and cognitive flexibility) there is narrower knowledge on its organization and contribution to task solution. The study tested different theoretical models about the structure and composition of EF. The correlation matrix of Miyake et al. (2000), which evaluated university students in a set of 15 EF tasks, was adopted. Model 1 displays a general factor and specific components. In mo...
Directory of Open Access Journals (Sweden)
Henry D Priest
Full Text Available Brachypodium distachyon is a close relative of many important cereal crops. Abiotic stress tolerance has a significant impact on productivity of agriculturally important food and feedstock crops. Analysis of the transcriptome of Brachypodium after chilling, high-salinity, drought, and heat stresses revealed diverse differential expression of many transcripts. Weighted Gene Co-Expression Network Analysis revealed 22 distinct gene modules with specific profiles of expression under each stress. Promoter analysis implicated short DNA sequences directly upstream of module members in the regulation of 21 of 22 modules. Functional analysis of module members revealed enrichment in functional terms for 10 of 22 network modules. Analysis of condition-specific correlations between differentially expressed gene pairs revealed extensive plasticity in the expression relationships of gene pairs. Photosynthesis, cell cycle, and cell wall expression modules were down-regulated by all abiotic stresses. Modules which were up-regulated by each abiotic stress fell into diverse and unique gene ontology GO categories. This study provides genomics resources and improves our understanding of abiotic stress responses of Brachypodium.
Theoretical Analysis of Tunable Single-Core Comb Filter Based on MZI
Directory of Open Access Journals (Sweden)
J. N. Sikta
2014-07-01
Full Text Available Normal 0 false false false EN-US X-NONE X-NONE In this work, a theoretical analysis of single core tunable comb filter based on Mach-Zehnder (M-Z interferometer is proposed and demonstrated. The proposed filter consists of one QWP, one HWP, one SMF and onePMF segment consists of two PMF lengths. Depending on the dynamic settings of wavelength of the input
Institute of Scientific and Technical Information of China (English)
ZHANG Jianhui; LU Jizhuang; XIA Qixiao; LI Hong
2007-01-01
A novel valveless piezoelectric pump with unsymmetrical ridges is presented at first. It ingeniously uti- lizes the inner space of its chamber by developing its chamber bottom into unsymmetrical ridges along the direction of the inlet and outlet of the pump. Hence, a series of cuneiform channels are asymmetrically and alternately formed between the unsymmetrical ridges and the piezoelectric vibrator, which enables the pump to form a one-way flow instead of the func- tion of the traditional diffuse or nozzle elements fitted outside the chamber. Then, by analyzing the vibration of the piezo- electric vibrator, the vibration deformation function and the equation of volume change are established. Meanwhile, the theoretical equation of the pump flow rate is established. Finally, a real valveless piezoelectric pump with unsymmetri- cal ridges is manufactured, and the flow rate of the pump is measured through experiments. It is proved that the theory is rational and correct by comparing the experimental flow rate and the theoretical flow rate. In addition, for calculating the theoretical flow rate, the positive and converse flow resis- tance coefficients of unsymmetrical ridges are measured through experiments, when one slope angle of the unsym- metrical ridges is 90° and another is changing from 20° to 60°, respectively.
Institute of Scientific and Technical Information of China (English)
CHEN Zhihua; YAN Xiangyu; SUN Ruirui; FENG Zhenchang; QIN Yali; ZHAO Jianbo
2007-01-01
The suspendome used as the roof of the VIP hall in Tianjin Museum was analyzed by ANASYS under the assumptions of hinged joints and rigid joints in up chord,respectively,and the results show that the member force and nodal displacement under the two assumptions have little difference.Thus,it is attained that the suspendome can be analyzed with the assumption of hinged joints.A full-scale test on the suspendome with half-cable and half-pipe was carried out.The loading system,arrangement of measuring points,and the test procedures are introduced.Also,a test on steel wire ropes for elastic module was carried out.The experimental and theoretical values of member forces and nodal displacements were compared and it showed that they accord well with each other under low-level load.While under high-level load,the experimental value was bigger than the theoretical value due to the influence of the test environment.With the increase of the load,tension of outside cables and looseness of inside cables occurred,which indicated that the prestressing value in inside cables should be properly assigned.Both the experimental and theoretical results verify that the suspendome has a wide application prospect with the advantages of perfect mechanical characteristics,low steel consumption,convenient construction and low cost.
Puente, Norma P; Chaikina, Elena I; Herath, Sumudu; Yamilov, Alexey
2011-02-20
We present results of experimental and theoretical studies of polarization-resolved light transmission through optical fiber with disorder generated in its germanium-doped core via UV radiation transmitted through a diffuser. In samples longer than a certain characteristic length, the power transmitted with preserved polarization is observed to be distributed over all forward-propagating modes, as evidenced by the Rayleigh negative exponential distribution of the near-field intensity at the output surface of the fiber. Furthermore, the transmitted power becomes also equally distributed over both polarizations. To describe the optical properties of the fibers with the experimentally induced disorder, a theoretical model based on coupled-mode theory is developed. The obtained analytical expression for the correlation function describing spatial properties of the disorder shows that it is highly anisotropic. Our calculations demonstrate that this experimentally controllable anisotropy can lead to suppression of the radiative leakage of the propagating modes, so that intermode coupling becomes the dominant scattering process. The obtained theoretical expressions for the polarization-resolved transmission fit very well with the experimental data, and the information extracted from the fit shows that radiative leakage is indeed small. The reported technique provides an easy way to fabricate different configurations of controlled disorder in optical fibers suitable for such applications as random fiber lasers.
Theoretical modeling and experimental analysis of solar still integrated with evacuated tubes
Panchal, Hitesh; Awasthi, Anuradha
2016-12-01
In this present research work, theoretical modeling of single slope, single basin solar still integrated with evacuated tubes has been performed based on energy balance equations. Major variables like water temperature, inner glass cover temperature and distillate output has been computed based on theoretical modeling. The experimental setup has been made from locally available materials and installed at Gujarat Power Engineering and Research Institute, Mehsana, Gujarat, India (23.5880°N, 72.3693°E) with 0.04 m depth during 6 months of time interval. From the series of experiments, it is found considerable increment in average distillate output of a solar still when integrated with evacuated tubes not only during daytime but also from night time. In all experimental cases, the correlation of coefficient (r) and root mean square percentage deviation of theoretical modeling and experimental study found good agreement with 0.97 < r < 0.98 and 10.22 < e < 38.4% respectively.
[What is personalistic bioethics? An analysys of its specificity and its theoretical foundations].
Burgos Velasco, Juan Manuel
2013-01-01
This article try to analyze why, although personalistic bioethics is expanding, there are so few theoretical studies on its characteristics and identity, and concludes it is due to a problem of lack of specificity. Personalistic bioethicists rely either on movements or institutions that have a weak theoretical foundation or in the realist philosophy taken in a very broad sense, which generates a problem of internal inconsistency due to its great diversity. To solve this problem the author proposes: 1) be aware of the existence of this theoretical problem; 2) solve it through the use of personalistic philosophy understood as a particular philosophical school of the XX century. In this sense, the author proposes: 1) a detailed description of personalistic philosophy; 2) states that a particular version, the modern ontological personalism, developed from an anthropological point of view by Wojtyla, from a bioethical point of view by Sgreccia and from the theory of personalism by Burgos is the best choice to put the foundations of personalistic bioethics. The author concludes exposing the contributions and limits of this theory for personalistic bioethics, and the steps that should be followed to promote it and develop it.
Directory of Open Access Journals (Sweden)
Yuliang Su
Full Text Available Stimulated reservoir volume (SRV fracturing in tight oil reservoirs often induces complex fracture-network growth, which has a fundamentally different formation mechanism from traditional planar bi-winged fracturing. To reveal the mechanism of fracture network propagation, this paper employs a modified displacement discontinuity method (DDM, mechanical mechanism analysis and initiation and propagation criteria for the theoretical model of fracture network propagation and its derivation. A reasonable solution of the theoretical model for a tight oil reservoir is obtained and verified by a numerical discrete method. Through theoretical calculation and computer programming, the variation rules of formation stress fields, hydraulic fracture propagation patterns (FPP and branch fracture propagation angles and pressures are analyzed. The results show that during the process of fracture propagation, the initial orientation of the principal stress deflects, and the stress fields at the fracture tips change dramatically in the region surrounding the fracture. Whether the ideal fracture network can be produced depends on the geological conditions and on the engineering treatments. This study has both theoretical significance and practical application value by contributing to a better understanding of fracture network propagation mechanisms in unconventional oil/gas reservoirs and to the improvement of the science and design efficiency of reservoir fracturing.