Turbulent thermal diffusion in strongly stratified turbulence: theory and experiments
Amir, G; Eidelman, A; Elperin, T; Kleeorin, N; Rogachevskii, I
2016-01-01
Turbulent thermal diffusion is a combined effect of the temperature stratified turbulence and inertia of small particles. It causes the appearance of a non-diffusive turbulent flux of particles in the direction of the turbulent heat flux. This non-diffusive turbulent flux of particles is proportional to the product of the mean particle number density and the effective velocity of inertial particles. The theory of this effect has been previously developed only for small temperature gradients and small Stokes numbers (Phys. Rev. Lett. {\\bf 76}, 224, 1996). In this study a generalized theory of turbulent thermal diffusion for arbitrary temperature gradients and Stokes numbers has been developed. The laboratory experiments in the oscillating grid turbulence and in the multi-fan produced turbulence have been performed to validate the theory of turbulent thermal diffusion in strongly stratified turbulent flows. It has been shown that the ratio of the effective velocity of inertial particles to the characteristic ve...
Topologically stratified energy minimizers in a product Abelian field theory
Han, Xiaosen; Yang, Yisong
2015-09-01
We study a recently developed product Abelian gauge field theory by Tong and Wong hosting magnetic impurities. We first obtain a necessary and sufficient condition for the existence of a unique solution realizing such impurities in the form of multiple vortices. We next reformulate the theory into an extended model that allows the coexistence of vortices and anti-vortices. The two Abelian gauge fields in the model induce two species of magnetic vortex-lines resulting from Ns vortices and Ps anti-vortices (s = 1, 2) realized as the zeros and poles of two complex-valued Higgs fields, respectively. An existence theorem is established for the governing equations over a compact Riemann surface S which states that a solution with prescribed N1, N2 vortices and P1, P2 anti-vortices of two designated species exists if and only if the inequalities
Topologically stratified energy minimizers in a product Abelian field theory
Xiaosen Han
2015-09-01
Full Text Available We study a recently developed product Abelian gauge field theory by Tong and Wong hosting magnetic impurities. We first obtain a necessary and sufficient condition for the existence of a unique solution realizing such impurities in the form of multiple vortices. We next reformulate the theory into an extended model that allows the coexistence of vortices and anti-vortices. The two Abelian gauge fields in the model induce two species of magnetic vortex-lines resulting from Ns vortices and Ps anti-vortices (s=1,2 realized as the zeros and poles of two complex-valued Higgs fields, respectively. An existence theorem is established for the governing equations over a compact Riemann surface S which states that a solution with prescribed N1, N2 vortices and P1,P2 anti-vortices of two designated species exists if and only if the inequalities |N1+N2−(P1+P2|<|S|π,|N1+2N2−(P1+2P2|<|S|π, hold simultaneously, which give bounds for the ‘differences’ of the vortex and anti-vortex numbers in terms of the total surface area of S. The minimum energy of these solutions is shown to assume the explicit value E=4π(N1+N2+P1+P2, given in terms of several topological invariants, measuring the total tension of the vortex-lines.
Topologically Stratified Energy Minimizers in a Product Abelian Field Theory
Han, Xiaosen
2015-01-01
The recently developed product Abelian gauge field theory by Tong and Wong hosting magnetic impurities is reformulated into an extended model that allows the coexistence of vortices and anti-vortices. The two Abelian gauge fields in the model induce two species of magnetic vortex-lines resulting from $N_s$ vortices and $P_s$ anti-vortices ($s=1,2$) realized as the zeros and poles of two complex-valued Higgs fields, respectively. An existence theorem is established for the governing equations over a compact Riemann surface $S$ which states that a solution with prescribed $N_1, N_2$ vortices and $P_1,P_2$ anti-vortices of two designated species exists if and only if the inequalities \\[ \\left|N_1+N_2-(P_1+P_2)\\right|<\\frac{|S|}{\\pi},\\quad \\left|N_1+2N_2-(P_1+2P_2)\\right|<\\frac{|S|}{\\pi}, \\] hold simultaneously, which give bounds for the `differences' of the vortex and anti-vortex numbers in terms of the total surface area of $S$. The minimum energy of these solutions is shown to assume the explicit value \\...
Coherence theory of electromagnetic wave propagation through stratified N-layer media
Hoenders, B.J.; Bertolotti, M.
The theory of second-order coherence in connection with wave propagation through a stratified N-layer (SNL) medium is developed. Especially, the influence of the SNL medium on the propagation of the coherence generated by a given state of coherence at the entrance plane of the medium is considered.
A new scoring system to stratify risk in unstable angina
Salzberg Simón
2003-08-01
Full Text Available Abstract Background We performed this study to develop a new scoring system to stratify different levels of risk in patients admitted to hospital with a diagnosis of unstable angina (UA, which is a complex syndrome that encompasses different outcomes. Many prognostic variables have been described but few efforts have been made to group them in order to enhance their individual predictive power. Methods In a first phase, 473 patients were prospectively analyzed to determine which factors were significantly associated with the in-hospital occurrence of refractory ischemia, acute myocardial infarction (AMI or death. A risk score ranging from 0 to 10 points was developed using a multivariate analysis. In a second phase, such score was validated in a new sample of 242 patients and it was finally applied to the entire population (n = 715. Results ST-segment deviation on the electrocardiogram, age ≥ 70 years, previous bypass surgery and troponin T ≥ 0.1 ng/mL were found as independent prognostic variables. A clear distinction was shown among categories of low, intermediate and high risk, defined according to the risk score. The incidence of the triple end-point was 6 %, 19.2 % and 44.7 % respectively, and the figures for AMI or death were 2 %, 11.4 % and 27.6 % respectively (p Conclusions This new scoring system is simple and easy to achieve. It allows a very good stratification of risk in patients having a clinical diagnosis of UA. They may be divided in three categories, which could be of help in the decision-making process.
Kim, Seulong
2016-01-01
Bi-isotropic media, which include isotropic chiral media and Tellegen media as special cases, are the most general form of linear isotropic media where the electric displacement and the magnetic induction are related to both the electric field and the magnetic intensity. In inhomogeneous bi-isotropic media, electromagnetic waves of two different polarizations are coupled to each other. In this paper, we develop a generalized version of the invariant imbedding method for the study of wave propagation in arbitrarily-inhomogeneous stratified bi-isotropic media, which can be used to solve the coupled wave propagation problem accurately and efficiently. We verify the validity and usefulness of the method by applying it to several examples, including the wave propagation in a uniform chiral slab, the surface wave excitation in a bilayer system made of a layer of Tellegen medium and a metal layer, and the mode conversion of transverse electromagnetic waves into longitudinal plasma oscillations in inhomogeneous Telle...
Banakh, Taras
2008-01-01
We introduce and study (metrically) quarter-stratifiable spaces and then apply them to generalize Rudin and Kuratowski-Montgomery theorems about the Baire and Borel complexity of separately continuous functions.
Macia, R.; Correig, A.M.
1987-01-01
Seismic wave propagation is described by a second order differential equation for medium desplacement. By Fourier transforming with respect to time and space, wave equation transforms into a system of first order linear differential equations for the Fourier transform of displacement and stress. This systen of differential equations is solved by means of Matrx Propagator and applied to the propagation of body waves in stratified media. The matrix propagators corresponding to P-SV and SH waves in homogeneous medium are found as an intermediate step to obtain the spectral response of body waves propagating through a stratified medium with homogeneous layers. (Author)
Fabiano, B.; Kersten, R.J.A.; Opschoor, G.; Pastorino, R.
2002-01-01
The occurrence of a rapid phase transition, or so-called explosive boiling, when a cold volatile liquid comes into contact with a hot liquid or hot surface is a potential hazard in industry. This study was focused on the explosive boiling potential of thermally stratified liquid-liquid systems that
Analysing stratified medicine business models and value systems: innovation-regulation interactions.
Mittra, James; Tait, Joyce
2012-09-15
Stratified medicine offers both opportunities and challenges to the conventional business models that drive pharmaceutical R&D. Given the increasingly unsustainable blockbuster model of drug development, due in part to maturing product pipelines, alongside increasing demands from regulators, healthcare providers and patients for higher standards of safety, efficacy and cost-effectiveness of new therapies, stratified medicine promises a range of benefits to pharmaceutical and diagnostic firms as well as healthcare providers and patients. However, the transition from 'blockbusters' to what might now be termed 'niche-busters' will require the adoption of new, innovative business models, the identification of different and perhaps novel types of value along the R&D pathway, and a smarter approach to regulation to facilitate innovation in this area. In this paper we apply the Innogen Centre's interdisciplinary ALSIS methodology, which we have developed for the analysis of life science innovation systems in contexts where the value creation process is lengthy, expensive and highly uncertain, to this emerging field of stratified medicine. In doing so, we consider the complex collaboration, timing, coordination and regulatory interactions that shape business models, value chains and value systems relevant to stratified medicine. More specifically, we explore in some depth two convergence models for co-development of a therapy and diagnostic before market authorisation, highlighting the regulatory requirements and policy initiatives within the broader value system environment that have a key role in determining the probable success and sustainability of these models.
The Universal Aspect Ratio of Vortices in Rotating Stratified Flows: Theory and Simulation
Hassanzadeh, Pedram; Gal, Patrice Le
2012-01-01
We derive a relationship for the vortex aspect ratio $\\alpha$ (vertical half-thickness over horizontal length scale) for steady and slowly evolving vortices in rotating stratified fluids, as a function of the Brunt-Vaisala frequencies within the vortex $N_c$ and in the background fluid outside the vortex $\\bar{N}$, the Coriolis parameter $f$, and the Rossby number $Ro$ of the vortex: $\\alpha^2 = Ro(1+Ro) f^2/(N_c^2-\\bar{N}^2)$. This relation is valid for cyclones and anticyclones in either the cyclostrophic or geostrophic regimes; it works with vortices in Boussinesq fluids or ideal gases, and the background density gradient need not be uniform. Our relation for $\\alpha$ has many consequences for equilibrium vortices in rotating stratified flows. For example, cyclones must have $N_c^2 > \\bar{N}^2$; weak anticyclones (with $|Ro| \\bar{N}^2$. We verify our relation for $\\alpha$ with numerical simulations of the three-dimensional Boussinesq equations for a wide variety of vortices, including: vortices that are i...
Understanding harmful algae in stratified systems: Review of progress and future directions
Berdalet, E.; McManus, M. A.; Ross, O. N.; Burchard, H.; Chavez, F. P.; Jaffe, J. S.; Jenkinson, I. R.; Kudela, R.; Lips, I.; Lips, U.; Lucas, A.; Rivas, D.; Ruiz-de la Torre, M. C.; Ryan, J.; Sullivan, J. M.; Yamazaki, H.
2014-03-01
The Global Ecology and Oceanography of Harmful Algal Blooms (GEOHAB) program of the Scientific Committee on Oceanic Research (SCOR) and the Intergovernmental Oceanographic Commission (IOC) of UNESCO, was created in 1999 to foster research on the ecological and oceanographic mechanisms underlying the population dynamics of harmful algal blooms (HABs). The ultimate goal of this research is to develop observational systems and models that will eventually enable the prediction of HABs and thereby minimize their impact on marine ecosystems, human health and economic activities. In August of 2012, a workshop was held under the umbrella of the GEOHAB program at the Monterey Bay Aquarium Research Institute (MBARI). The over arching goal of this workshop was to review the current understanding of the processes governing the structure and dynamics of HABs in stratified systems, and to identify how best to couple physical/chemical and biological measurements at appropriate spatial and temporal scales to quantify the dynamics of HABs in these systems, paying particular attention to thin layers. This contribution provides a review of recent progress in the field of HAB research in stratified systems including thin layers, and identifies the gaps in knowledge that our scientific community should strive to understand in the next decade.
Bergstra, J A; van Vlijmen, S F M
2011-01-01
The terminology of sourcing, outsourcing and insourcing is developed in detail on the basis of the preliminary definitions of outsourcing and insourcing and related activities and competences as given in our three previous papers on business mereology, on the concept of a sourcement, and on outsourcing competence respectively. Besides providing more a detailed semantic analysis we will introduce, explain, and illustrate a number of additional concepts including: principal unit of a sourcement, theme of a sourcement, current sourcement, (un)stable sourcement, and sourcement transformation. A three level terminology is designed: (i) factual level: operational facts that hold for sourcements including histories thereof, (ii) business level: roles and objectives of various parts of the factual level description, thus explaining each partner's business process and business objectives, (iii) contract level: specification of intended facts and intended business models as found at the business level. Orthogonal to th...
Bergstra, J.; Delen, G.; van Vlijmen, B.
2011-01-01
The terminology of sourcing, outsourcing and insourcing is developed in detail on the basis of the preliminary definitions of outsourcing and insourcing and related activities and competences as given in our three previous papers on business mereology, on the concept of a sourcement, and on outsourc
Muroki, T. [Kanagawa Inst. of Technology, Dept. of Mechanical Engineering, Kanagawa (Japan); Moriyoshi, Y. [Chiba Univ., Dept. of Electronics and Mechanical Engineering, Chiba (Japan)
2000-11-01
In a stratified charge engine, a glow plug pilot flame ignition system has been compared with a spark-ignition system for a model stratified charge Wankel combustion chamber. A motored two-stroke diesel engine was operated as a rapid compression and expansion machine with the cylinder head replaced by a model Wankel combustion chamber designed to simulate the temporal changes of air flow and pressure fields inside the chamber of an actual engine. It was found that the pilot flame ignition system had better ignitability and improved combustion characteristics, especially in the lean mixture range, relative to the spark-ignition system. (Author)
Oh, Junho; Kim, Kue-Young; Han, Weon Shik; Park, Eungyu; Kim, Jeong-Chan
2015-10-01
Multiple scenarios of upward CO2 migration driven by both injection-induced pressure and buoyancy force were investigated in a horizontally and vertically stratified core utilizing a core-flooding system with a 2-D X-ray scanner. Two reservoir-type scenarios were considered: (1) the terrestrial reservoir scenario (10 MPa and 50°C), where CO2 exists in a supercritical state and (2) the deep-sea sediment reservoir scenario (28 MPa and 25°C), where CO2 is stored in the liquid phase. The core-flooding experiments showed a 36% increase in migration rate in the vertical core setting compared with the horizontal setting, indicating the significance of the buoyancy force under the terrestrial reservoir scenario. Under both reservoir conditions, the injected CO2 tended to find a preferential flow path (low capillary entry pressure and high-permeability (high-k) path) and bypass the unfavorable pathways, leaving low CO2 saturation in the low-permeability (low-k) layers. No distinctive fingering was observed as the CO2 moved upward, and the CO2 movement was primarily controlled by media heterogeneity. The CO2 saturation in the low-k layers exhibited a more sensitive response to injection rates, implying that the increase in CO2 injection rates could be more effective in terms of storage capacity in the low-k layers in a stratified reservoir. Under the deep-sea sediment condition, the storage potential of liquid CO2 was more than twice as high as that of supercritical CO2 under the terrestrial reservoir scenario. In the end, multiphase transport simulations were conducted to assess the effects of heterogeneity on the spatial variation of pressure buildup, CO2 saturation, and CO2 flux. Finally, we showed that a high gravity number (Ngr) tended to be more influenced by the heterogeneity of the porous media.
Huang, S.R. [Feng Chia Univ., Taichung (Taiwan, Province of China). Electrical Engineering Dept.
1997-03-01
A combined Monte Carlo and optimum stratified sampling method is presented to better estimate copper loss of a transmission system during a prespecified future period. This design seeks to enhance the precision of copper loss of transmission system estimation, while reducing computation time. The techniques included are optimum stratified sampling and separate ratio estimation. The optimum stratification rule aims to remove any judgemental input and to render the stratification process entirely mechanistic. The estimator, provided by ratio statistics of the sample, can avoid identification of the regression model and thus save computation time. The effectiveness of precision improvement is demonstrated. (UK)
Callier, Frank M.; Desoer, Charles A.
1991-01-01
The aim of this book is to provide a systematic and rigorous access to the main topics of linear state-space system theory in both the continuous-time case and the discrete-time case; and the I/O description of linear systems. The main thrusts of the work are the analysis of system descriptions and derivations of their properties, LQ-optimal control, state feedback and state estimation, and MIMO unity-feedback systems.
Doria, Gino; Koch, Giorgio; Strom, Roberto
1979-01-01
This volume collects the contributions presented at the "Working Conference on System Theory in Immunology", held in Rome, May 1978. The aim of the Conference was to bring together immunologists on one side and experts in system theory and applied mathematics on the other, in order to identify problems of common interest and to establish a network of joint effort toward their solution. The methodologies of system theory for processing experimental data and for describing dynamical phenomena could indeed contribute significantly to the under standing of basic immunological facts. Conversely, the complexity of experimental results and of interpretative models should stimulate mathematicians to formulate new problems and to design appropriate procedures of analysis. The multitude of scientific publications in theoretical biology, appeared in recent years, confirms this trend and calls for extensive interaction between mat- matics and immunology. The material of this volume is divided into five sections, along ...
Applied multidimensional systems theory
Bose, Nirmal K
2017-01-01
Revised and updated, this concise new edition of the pioneering book on multidimensional signal processing is ideal for a new generation of students. Multidimensional systems or m-D systems are the necessary mathematical background for modern digital image processing with applications in biomedicine, X-ray technology and satellite communications. Serving as a firm basis for graduate engineering students and researchers seeking applications in mathematical theories, this edition eschews detailed mathematical theory not useful to students. Presentation of the theory has been revised to make it more readable for students, and introduce some new topics that are emerging as multidimensional DSP topics in the interdisciplinary fields of image processing. New topics include Groebner bases, wavelets, and filter banks.
Design Theory in Information Systems
Shirley Gregor
2002-11-01
Full Text Available The aim of this paper is to explore an important category of information systems knowledge that is termed “design theory”. This knowledge is distinguished as the fifth of five types of theory: (i theory for analysing and describing, (ii theory for understanding, (iii theory for predicting, (iv theory for explaining and predicting, and (v theory for design and action. Examples of design theory in information systems are provided, with associated research methods. The limited understanding and recognition of this type of theory in information systems indicates that further debate concerning its nature and role in our discipline is needed.
Dekkers, Rob
2017-01-01
Offering an up-to-date account of systems theories and its applications, this book provides a different way of resolving problems and addressing challenges in a swift and practical way, without losing overview and grip on the details. From this perspective, it offers a different way of thinking in order to incorporate different perspectives and to consider multiple aspects of any given problem. Drawing examples from a wide range of disciplines, it also presents worked cases to illustrate the principles. The multidisciplinary perspective and the formal approach to modelling of systems and processes of ‘Applied Systems Theory’ makes it suitable for managers, engineers, students, researchers, academics and professionals from a wide range of disciplines; they can use this ‘toolbox’ for describing, analysing and designing biological, engineering and organisational systems as well as getting a better understanding of societal problems. This revised, updated and expanded second edition includes coverage of a...
Family systems theory, attachment theory, and culture.
Rothbaum, Fred; Rosen, Karen; Ujiie, Tatsuo; Uchida, Nobuko
2002-01-01
Family systems theory and attachment theory have important similarities and complementarities. Here we consider two areas in which the theories converge: (a) in family system theorists' description of an overly close, or "enmeshed," mother-child dyad, which attachment theorists conceptualize as the interaction of children's ambivalent attachment and mothers' preoccupied attachment; (b) in family system theorists' description of the "pursuer-distance cycle" of marital conflict, which attachment theorists conceptualize as the interaction of preoccupied and dismissive partners. We briefly review family systems theory evidence, and more extensively review attachment theory evidence, pertaining to these points of convergence. We also review cross-cultural research, which leads us to conclude that the dynamics described in both theories reflect, in part, Western ways of thinking and Western patterns of relatedness. Evidence from Japan suggests that extremely close ties between mother and child are perceived as adaptive, and are more common, and that children experience less adverse effects from such relationships than do children in the West. Moreover, in Japan there is less emphasis on the importance of the exclusive spousal relationship, and less need for the mother and father to find time alone to rekindle romantic, intimate feelings and to resolve conflicts by openly communicating their differences. Thus, the "maladaptive" pattern frequently cited by Western theorists of an extremely close mother-child relationship, an unromantic, conflictual marriage characterized by little verbal communication and a peripheral, distant father, may function very differently in other cultures. While we believe that both theories will be greatly enriched by their integration, we caution against the application of either theory outside the cultures in which they were developed.
Dekkers, Rob
2014-01-01
Offering an up-to-date account of systems theories and its applications, this book provides a different way of resolving problems and addressing challenges in a swift and practical way, without losing overview and not having a grip on the details. From this perspective, it offers a different way of thinking in order to incorporate different perspectives and to consider multiple aspects of any given problem. Drawing examples from a wide range of disciplines, it also presents worked cases to illustrate the principles. The multidisciplinary perspective and the formal approach to modelling of syst
Dwivedi, Yogesh K; Schneberger, Scott L
2011-01-01
The overall mission of this book is to provide a comprehensive understanding and coverage of the various theories and models used in IS research. Specifically, it aims to focus on the following key objectives: To describe the various theories and models applicable to studying IS/IT management issues. To outline and describe, for each of the various theories and models, independent and dependent constructs, reference discipline/originating area, originating author(s), seminal articles, level of analysis (i.e. firm, individual, industry) and links with other theories. To provide a critical revie
Information theory of molecular systems
Nalewajski, Roman F
2006-01-01
As well as providing a unified outlook on physics, Information Theory (IT) has numerous applications in chemistry and biology owing to its ability to provide a measure of the entropy/information contained within probability distributions and criteria of their information ""distance"" (similarity) and independence. Information Theory of Molecular Systems applies standard IT to classical problems in the theory of electronic structure and chemical reactivity. The book starts by introducing the basic concepts of modern electronic structure/reactivity theory based upon the Density Functional Theory
Yield reduction and reduced crop vigor, resulting from soil acidification, are of increasing concern in eastern Washington and northern Idaho. In this region, soil pH has been decreasing at an accelerated rate, primarily due to the long-term use of ammonium based fertilizers. In no-till systems, the...
Ergodic theory and dynamical systems
Coudène, Yves
2016-01-01
This textbook is a self-contained and easy-to-read introduction to ergodic theory and the theory of dynamical systems, with a particular emphasis on chaotic dynamics. This book contains a broad selection of topics and explores the fundamental ideas of the subject. Starting with basic notions such as ergodicity, mixing, and isomorphisms of dynamical systems, the book then focuses on several chaotic transformations with hyperbolic dynamics, before moving on to topics such as entropy, information theory, ergodic decomposition and measurable partitions. Detailed explanations are accompanied by numerous examples, including interval maps, Bernoulli shifts, toral endomorphisms, geodesic flow on negatively curved manifolds, Morse-Smale systems, rational maps on the Riemann sphere and strange attractors. Ergodic Theory and Dynamical Systems will appeal to graduate students as well as researchers looking for an introduction to the subject. While gentle on the beginning student, the book also contains a number of commen...
Thermal Performance of a Large Low Flow Solar Heating System with a Highly Thermally Stratified Tank
Furbo, Simon; Vejen, Niels Kristian; Shah, Louise Jivan
2005-01-01
are facing west. The collector tilt is 15° from horizontal for all collectors. Both the east-facing and the west-facing collectors have their own solar collector loop, circulation pump, external heat exchanger and control system. The external heat exchangers are used to transfer the heat from the solar...... collector fluid to the domestic water. The domestic water is pumped from the bottom of the hot-water tank to the heat exchanger and back to the hot-water tank through stratification inlet pipes. The return flow from the DHW circulation pipe also enters the tank through stratification inlet pipes. The tank...... performance and for the excellent utilization of the solar radiation is the high hot-water consumption and the good system design making use of external heat exchangers and stratification inlet pipes....
A Contextualised General Systems Theory
Kirsty Kitto
2014-01-01
A system is something that can be separated from its surrounds, but this definition leaves much scope for refinement. Starting with the notion of measurement, we explore increasingly contextual system behaviour and identify three major forms of contextuality that might be exhibited by a system: (1) between components; (2) between system and experimental method; and (3) between a system and its environment. Quantum theory is shown to provide a highly useful formalism from which all three forms...
Linear systems theory revisited
Willigenburg, van L.G.; Koning, de W.L.
2008-01-01
This paper investigates and clarifies how different definitions of reachability, observability, controllability, reconstructability and minimality that appear in the control literature, may be equivalent or different, depending on the type of linear system. The differences are caused by (1) whether
Predominantly Low Metallicities Measured in a Stratified Sample of Lyman Limit Systems at z=3.7
Glidden, Ana; Cooksey, Kathy L; Simcoe, Robert A; O'Meara, John M
2016-01-01
We analyzed metallicities for 33 z=3.4-4.2 absorption line systems with large neutral hydrogen column densities, drawn from a sample of H I-selected of Lyman limit systems (LLSs) identified in Sloan Digital Sky Survey (SDSS) quasar spectra, and stratified based on metal line features. We obtained higher-resolution spectra with the Keck Echellette Spectrograph and Imager (ESI), selecting targets according to our stratification scheme in an effort to fully sample the LLS population metallicity distribution. We established a plausible range of H I column densities and measured the metal column densities (or limits) for ions of carbon, silicon, and aluminum. With simulations, we found ionization-corrected metallicities or upper limits, when appropriate. Interestingly, our ionization models were better constrained with enhanced {\\alpha}-to-aluminum abundances, with a median abundance ratio of [{\\alpha}/Al]=0.3. Measured metallicities were generally low, ranging from [M/H]=-3 to -1.68, with even lower metallicities...
On Restructurable Control System Theory
Athans, M.
1983-01-01
The state of stochastic system and control theory as it impacts restructurable control issues is addressed. The multivariable characteristics of the control problem are addressed. The failure detection/identification problem is discussed as a multi-hypothesis testing problem. Control strategy reconfiguration, static multivariable controls, static failure hypothesis testing, dynamic multivariable controls, fault-tolerant control theory, dynamic hypothesis testing, generalized likelihood ratio (GLR) methods, and adaptive control are discussed.
A Contextualised General Systems Theory
Kirsty Kitto
2014-10-01
Full Text Available A system is something that can be separated from its surrounds, but this definition leaves much scope for refinement. Starting with the notion of measurement, we explore increasingly contextual system behaviour and identify three major forms of contextuality that might be exhibited by a system: (1 between components; (2 between system and experimental method; and (3 between a system and its environment. Quantum theory is shown to provide a highly useful formalism from which all three forms of contextuality can be analysed, offering numerous tests for contextual behaviour, as well as modelling possibilities for systems that do indeed display it. I conclude with the introduction of a contextualised general systems theory based on an extension of this formalism
Pitta Srinivasa Rao
2008-01-01
Full Text Available The main objective of the present work is to make a computational study of stratified scavenging system in two-stroke medium capacity engines to reduce or to curb the emissions from the two-stroke engines. The 3-D flows within the cylinder are simulated using computational fluid dynamics and the code Fluent 6. Flow structures in the transfer ports and the exhaust port are predicted without the stratification and with the stratification, and are well predicted. The total pressure and velocity map from computation provided comprehensive information on the scavenging and stratification phenomenon. Analysis is carried out for the transfer ports flow and the extra port in the transfer port along with the exhaust port when the piston is moving from the top dead center to the bottom dead center, as the ports are closed, half open, three forth open, and full port opening. An unstructured cell is adopted for meshing the geometry created in CATIA software. Flow is simulated by solving governing equations namely conservation of mass momentum and energy using SIMPLE algorithm. Turbulence is modeled by high Reynolds number version k-e model. Experimental measurements are made for validating the numerical prediction. Good agreement is observed between predicted result and experimental data; that the stratification had significantly reduced the emissions and fuel economy is achieved.
General Systems Theory and Instructional Systems Design.
Salisbury, David F.
1990-01-01
Describes basic concepts in the field of general systems theory (GST) and identifies commonalities that exist between GST and instructional systems design (ISD). Models and diagrams that depict system elements in ISD are presented, and two matrices that show how GST has been used in ISD literature are included. (11 references) (LRW)
Breugel, Y. van; Schouten, S.; Paetzel, M.; Nordeide, R.; Sinninghe Damsté, J.S.
2005-01-01
A negative carbon isotope shift in sedimentary organic carbon deposited in stratified marine and lacustrine systems has often been inferred to be a consequence of the process of recycling of respired and, therefore, 13C-depleted, dissolved inorganic carbon (DIC) formed from mineralization of descend
Systems Theory and Systems Approach to Leadership
Dr.Sc. Berim Ramosaj
2014-06-01
Full Text Available Systems theory is product of the efforts of many researchers to create an intermediate field of coexistence of all sciences. If not for anything else, because of the magnitude that the use of systemic thinking and systemic approach has taken, it has become undisputed among the theories. Systems theory not only provides a glossary of terms with which researchers from different fields can be understood, but provides a framework for the presentation and interpretation of phenomena and realities. This paper addresses a systematic approach to leadership, as an attempt to dredge leadership and systems theory literature to find the meeting point. Systems approach is not an approach to leadership in terms of a manner of leader’s work, but it’s the leader's determination to factorize in his leadership the external environment and relationships with and among elements. Leader without followers is unable to exercise his leadership and to ensure their conviction he should provide a system, a structure, a purpose, despite the alternative chaos. Systems approach clarifies the thought on the complexity and dynamism of the environment and provides a framework for building ideas. If the general system theory is the skeleton of science (Boulding: 1956, this article aims to replenish it with leadership muscles by prominent authors who have written on systems theory and leadership, as well as through original ideas. In this work analytical methods were used (by analyzing approaches individually as well as synthetic methods (by assaying individual approaches in context of entirety. The work is a critical review of literature as well as a deductive analysis mingled with models proposed by authors through inductive analysis. Meta-analysis has been used to dissect the interaction and interdependence between leadership approaches.
Vincze, Miklos; Harlander, Uwe; Gal, Patrice Le
2016-01-01
A water-filled differentially heated rotating annulus with initially prepared stable vertical salinity profiles is studied in the laboratory. Based on two-dimensional horizontal particle image velocimetry (PIV) data, and infrared camera visualizations, we describe the appearance and the characteristics of the baroclinic instability in this original configuration. First, we show that when the salinity profile is linear and confined between two non stratified layers at top and bottom, only two separate shallow fluid layers can be destabilized. These unstable layers appear nearby the top and the bottom of the tank with a stratified motionless zone between them. This laboratory arrangement is thus particularly interesting to model geophysical or astrophysical situations where stratified regions are often juxtaposed to convective ones. Then, for more general but stable initial density profiles, statistical measures are introduced to quantify the extent of the baroclinic instability at given depths and to analyze t...
Gestalt Therapy and General System Theory.
Whitner, Phillip A.
While General Systems Theory (GST) concepts appear to be applicable in explaining some of the phenomena that occur in a Gestalt Therapy group, research is needed to support this assumption. General Systems Theory may not be a group theory per se. Instead, GST may be a theory about groups. A meta-theory exists where its value and usefulness is…
Dynamical systems V bifurcation theory and catastrophe theory
1994-01-01
Bifurcation theory and catastrophe theory are two of the best known areas within the field of dynamical systems. Both are studies of smooth systems, focusing on properties that seem to be manifestly non-smooth. Bifurcation theory is concerned with the sudden changes that occur in a system when one or more parameters are varied. Examples of such are familiar to students of differential equations, from phase portraits. Moreover, understanding the bifurcations of the differential equations that describe real physical systems provides important information about the behavior of the systems. Catastrophe theory became quite famous during the 1970's, mostly because of the sensation caused by the usually less than rigorous applications of its principal ideas to "hot topics", such as the characterization of personalities and the difference between a "genius" and a "maniac". Catastrophe theory is accurately described as singularity theory and its (genuine) applications. The authors of this book, the first printing of w...
Vincze, Miklos; Borcia, Ion; Harlander, Uwe; Le Gal, Patrice
2016-12-01
A water-filled differentially heated rotating annulus with initially prepared stable vertical salinity profiles is studied in the laboratory. Based on two-dimensional horizontal particle image velocimetry data and infrared camera visualizations, we describe the appearance and the characteristics of the baroclinic instability in this original configuration. First, we show that when the salinity profile is linear and confined between two non-stratified layers at top and bottom, only two separate shallow fluid layers can be destabilized. These unstable layers appear nearby the top and the bottom of the tank with a stratified motionless zone between them. This laboratory arrangement is thus particularly interesting to model geophysical or astrophysical situations where stratified regions are often juxtaposed to convective ones. Then, for more general but stable initial density profiles, statistical measures are introduced to quantify the extent of the baroclinic instability at given depths and to analyze the connections between this depth-dependence and the vertical salinity profiles. We find that, although the presence of stable stratification generally hinders full-depth overturning, double-diffusive convection can lead to development of multicellular sideways convection in shallow layers and subsequently to a multilayered baroclinic instability. Therefore we conclude that by decreasing the characteristic vertical scale of the flow, stratification may even enhance the formation of cyclonic and anticyclonic eddies (and thus, mixing) in a local sense.
Medium Theory and Social Systems
Tække, Jesper
The paper first gives a tentative theoretical explanation of the concept of media, based on the dichotomies of actual/potential (meaning), form/medium (appearance), and substratum/material content (extension in time and space). This theoretical explanation presents...... the possibility for observation both of a social micro and a social macro level from a medium perspective. In the next section the paper frames the macro level by a tentative synthesis of the medium theory and the sociological systems theory briefly describing a socio...... seen as medium for formation. Finally the paper takes the micro level perspective by applying the theory to newsgroups, interpreting them as self-organizing interactive systems giving a differentiated and diversified scope for social inclusion. ...
A Fixpoint Semantics for Stratified Databases
沈一栋
1993-01-01
Przmusinski extended the notion of stratified logic programs,developed by Apt,Blair and Walker,and by van Gelder,to stratified databases that allow both negative premises and disjunctive consequents.However,he did not provide a fixpoint theory for such class of databases.On the other hand,although a fixpoint semantics has been developed by Minker and Rajasekar for non-Horn logic programs,it is tantamount to traditional minimal model semantics which is not sufficient to capture the intended meaning of negation in the premises of clauses in stratified databases.In this paper,a fixpoint approach to stratified databases is developed,which corresponds with the perfect model semantics.Moreover,algorithms are proposed for computing the set of perfect models of a stratified database.
IMMANUEL WALLERSTEIN'S WORLD SYSTEM THEORY
Cosma Sorinel
2010-12-01
Full Text Available World-systems analysis is not a theory, but an approach to social analysis and social change developed, among others by the Immanuel Wallerstein. Professor Wallerstein writes in three domains of world-systems analysis: the historical development of the modern world-system; the contemporary crisis of the capitalist world-economy; the structures of knowledge. The American anlyst rejects the notion of a "Third World", claiming there is only one world connected by a complex network of economic exchange relationship. Our world system is characterized by mechanisms which bring about a redistribution of resources from the periphery to the core. His analytical approach has made a significant impact and established an institutional base devoted to the general approach.
Language theory and expert systems
Attilio Agodi
1988-11-01
Full Text Available Some remarks on the problem of knowledge representation and processing, as recognized in connection with the use of computers in the scientific research work, emphasizes the relevance of these problems for the studies on both the theory of languages and the expert system. A consideration of the common traits in the recent history of these studies, with reference to the use of computers on texts in natural language motivates the introduction of set theoretic and algebraic methods, suitable for applications in the analysis and in the automatic treatment of languages, based on the concept of model sets and on relational structures suggested from the connections between syntax and semantics evidenced in some example of sub-languages corresponding to theories of different classes of physical phenomena. Some details of these methods are evidenced, which have already successfully used or whose applications appears suggestive of interesting development.
Scheduling theory, algorithms, and systems
Pinedo, Michael L
2016-01-01
This new edition of the well-established text Scheduling: Theory, Algorithms, and Systems provides an up-to-date coverage of important theoretical models in the scheduling literature as well as important scheduling problems that appear in the real world. The accompanying website includes supplementary material in the form of slide-shows from industry as well as movies that show actual implementations of scheduling systems. The main structure of the book, as per previous editions, consists of three parts. The first part focuses on deterministic scheduling and the related combinatorial problems. The second part covers probabilistic scheduling models; in this part it is assumed that processing times and other problem data are random and not known in advance. The third part deals with scheduling in practice; it covers heuristics that are popular with practitioners and discusses system design and implementation issues. All three parts of this new edition have been revamped, streamlined, and extended. The reference...
Applications of the Theory of Technical Systems
Andreasen, Mogens Myrup; McAloone, Timothy Charles
2008-01-01
This paper uses the development and applications of Hubka’s Theory of Technical Systems (TTS) at DTU as an example of the power of the theory, the necessity of detailing and fitting the theory, and the role of a theory as a basis for research.At the same time the paper is a balance of the influence...
Representation Theory and Holonomic Systems
Etingof, Pavel Ilyich
1994-01-01
The main goal of this dissertation is a systematic study of the holonomic systems of differential and difference equations arising in the representation theory of affine and quantum affine Lie algebras. The first example of such a system appeared in 1984 in the work of V. Knizhnik and A. Zamolodchikov (KZ)); they showed that matrix elements of intertwining operators between certain representations of an affine Lie algebra (which are analytic matrix-valued functions of several complex variables) satisfy a commutative system of first-order linear partial differential equations, which are now called the Knizhnik-Zamolodchikov equations. This work is explained in Chapter 2. Later, in 1991, I. Frenkel and N. Reshetikhin (FR) generalized the KZ equations to the case of matrix elements of intertwiners for quantum affine algebras, and obtained the quantum KZ equations --a holonomic system of difference equations with matrix coefficients.^1 These results are stated and proved in Chapter 3 (our proof is somewhat different from that of Frenkel-Reshetikhin; it is similar to the proof given in (ITIJMN)). Both KZ and quantum KZ equations have rational coefficients. After a change of variables these coefficients become trigonometric. Our goal was to obtain holonomic systems of equations with elliptic coefficients from representation theory. The idea how to do it is already contained in the papers (Ber, BF, FR): one should consider traces of intertwiners instead of matrix elements, i.e. correlation functions on a genus 1 Riemann surface rather than genus zero Riemann surface. However, attempts to realize this idea met some difficulties: it turned out that it was impossible to write down a holonomic system of equations for traces. We offer two ways to go around this difficulty. One of the possible ways is to change the definition of a trace by twisting it by an automorphism of the affine Dynkin diagram. In the classical case this project is realized in Chapter 4, which relies on
Enterprise Modelling supported by Manufacturing Systems Theory
MYKLEBUST, Odd
2002-01-01
There exist today a large number of enterprise models or enterprise modelling approaches. In a study of standards and project developed models there are two approaches: CIMOSA “The Open Systems Architecture for CIM” and GERAM, “Generalised Enterprise Reference Architecture”, which show a system orientation that can be further followed as interesting research topics for a system theory oriented approach for enterprise models. In the selection of system theories, manufacturing system theory...
Linear response theory for quantum open systems
Wei, J. H.; Yan, YiJing
2011-01-01
Basing on the theory of Feynman's influence functional and its hierarchical equations of motion, we develop a linear response theory for quantum open systems. Our theory provides an effective way to calculate dynamical observables of a quantum open system at its steady-state, which can be applied to various fields of non-equilibrium condensed matter physics.
Developing Systemic Theories Requires Formal Methods
Gobet, Fernand
2012-01-01
Ziegler and Phillipson (Z&P) advance an interesting and ambitious proposal, whereby current analytical/mechanistic theories of gifted education are replaced by systemic theories. In this commentary, the author focuses on the pros and cons of using systemic theories. He argues that Z&P's proposal both goes too far and not far enough. The future of…
Family Systems Theory in the Workplace.
Rogers, Vivian
This paper presents a summary of Murray Brown's family systems theory as it applies to the workplace, lists some indicators of when a system is working well, and cites some other guidelines for gauging and improving one's own functioning in the work system. Major concepts of Bowen's theory include: (1) the family and the workplace are systems; (2)…
Family Systems Theory in the Workplace.
Rogers, Vivian
This paper presents a summary of Murray Brown's family systems theory as it applies to the workplace, lists some indicators of when a system is working well, and cites some other guidelines for gauging and improving one's own functioning in the work system. Major concepts of Bowen's theory include: (1) the family and the workplace are systems; (2)…
Hossain, Delowar; Samad, Abdus; Alam, Mahmud
2017-06-01
The ion-slip effects on unsteady MHD free convection flow past an infinite vertical porous plate with the effect of temperature stratified porous medium in a rotating system with viscous dissipation and Joule heating has been studied numerically. Introducing a time dependent suction to the plate, a similarity procedure has been adopted by taking a time dependent similarity parameter. The governing differential equations are transformed by introducing usual similarity variables. The resultant equations are solved numerically using Runge-Kutta method along with shooting technique. Resulting non-dimensional velocity and temperature profiles are then presented graphically for different values of the parameters entering into the problem.
General Systems Theory and Instructional Design.
Salisbury, David F.
The use of general systems theory in the field of instructional systems design (ISD) is explored in this paper. Drawing on work by Young, the writings of 12 representative ISD writers and researchers were surveyed to determine the use of 60 general systems theory concepts by the individual authors. The average number of concepts used by these…
World-Systems Theory and Feminist Scholarship.
Smith, Joan
World systems theory and feminist scholarship each have a great deal to offer the other, but the connections between the two have not often been recognized. The potential contributions from world systems theory include: (1) its understanding of history, (2) its understanding of what that history comprises, and (3) how it employs Marxist historical…
Theories are knowledge organizing systems (KOS)
Hjørland, Birger
2015-01-01
The notion “theory” is a neglected concept in the field of information science and knowledge organization (KO) as well as generally in philosophy and in many other fields, although there are exceptions from this general neglect (e.g., the so-called “theory theory” in cognitive psychology......-laden. The concept of knowledge organization system (KOS) is briefly introduced and discussed. A theory is a fundamental form of KOS and theories are the point of departure of any KOS. It is generally understood in KO that concepts are the units of KOS, but the theory-dependence of concepts brings theories...
Titchmarsh-Weyl theory for canonical systems
Keshav Raj Acharya
2014-11-01
Full Text Available The main purpose of this paper is to develop Titchmarsh- Weyl theory of canonical systems. To this end, we first observe the fact that Schrodinger and Jacobi equations can be written into canonical systems. We then discuss the theory of Weyl m-function for canonical systems and establish the relation between the Weyl m-functions of Schrodinger equations and that of canonical systems which involve Schrodinger equations.
Control Systems and Number Theory
Fuhuo Li
2012-01-01
and PID-controllers are applied successfully in the EV control by J.-Y. Cao and B.-G. Cao 2006 and Cao et al. 2007, which we may unify in our framework. Finally, we mention some similarities between control theory and zeta-functions.
Learning theory and system identification; Gakushu riron to system dotei
Adachi, S. [Utsunomiya Univ. (Japan). Faculty of Engineering
1998-04-10
The relationship between learning theory and system identification theory is described. The learning theory is mainly being studied by neural network community, while the system identification theory is mainly being discussed in the community of control system design and failure detection. The relation between the two theories has been studied. In this paper, the relation is explained by focusing on the following two points: (1) The relationship between learning method such as error reverse propagation method and on-line system identification is discussed from the viewpoint of robust estimation. (2) The relationship between PAC (probably approximately correct) learning which is recently attracting the attention among many learning theories and system identification theories is investigated. 33 refs.
The Systems Theory Framework of Career Development
McMahon, Mary
2011-01-01
The Systems Theory Framework (STF; McMahon & Patton, 1995; Patton & McMahon, 2006) of career development was proposed as a metatheoretical framework that accommodates the contribution of all theories and offers an integrative and coherent framework of career influences. In this article, the author provides an overview of the STF, outlines its…
Theories are knowledge organizing systems (KOS)
Hjørland, Birger
2015-01-01
The notion “theory” is a neglected concept in the field of information science and knowledge organization (KO) as well as generally in philosophy and in many other fields, although there are exceptions from this general neglect (e.g., the so-called “theory theory” in cognitive psychology). This a......The notion “theory” is a neglected concept in the field of information science and knowledge organization (KO) as well as generally in philosophy and in many other fields, although there are exceptions from this general neglect (e.g., the so-called “theory theory” in cognitive psychology......). This article introduces different conceptions of “theory” and argues that a theory is a statement or a conception, which may be questioned and which is connected with background assumptions. Theories form interconnected systems of grand, middle rank and micro theories; also practice and artifacts are theory...
Higher Spin Lifshitz Theory and Integrable Systems
Gutperle, Michael
2014-01-01
In this note we construct asymptotically Lifshitz spacetimes in the Chern-Simons formulation of three dimensional higher spin gravity and relate the resulting theories to integrable systems which are elements of the KdV hierarchy.
Fluttering in Stratified Flows
Lam, Try; Vincent, Lionel; Kanso, Eva
2016-11-01
The descent motion of heavy objects under the influence of gravitational and aerodynamic forces is relevant to many branches of engineering and science. Examples range from estimating the behavior of re-entry space vehicles to studying the settlement of marine larvae and its influence on underwater ecology. The behavior of regularly shaped objects freely falling in homogeneous fluids is relatively well understood. For example, the complex interaction of a rigid coin with the surrounding fluid will cause it to either fall steadily, flutter, tumble, or be chaotic. Less is known about the effect of density stratification on the descent behavior. Here, we experimentally investigate the descent of discs in both pure water and in a linearly salt-stratified fluids where the density is varied from 1.0 to 1.14 of that of water where the Brunt-Vaisala frequency is 1.7 rad/sec and the Froude number Fr robots for space exploration and underwater missions.
Emergent "Quantum" Theory in Complex Adaptive Systems.
Minic, Djordje; Pajevic, Sinisa
2016-04-30
Motivated by the question of stability, in this letter we argue that an effective quantum-like theory can emerge in complex adaptive systems. In the concrete example of stochastic Lotka-Volterra dynamics, the relevant effective "Planck constant" associated with such emergent "quantum" theory has the dimensions of the square of the unit of time. Such an emergent quantum-like theory has inherently non-classical stability as well as coherent properties that are not, in principle, endangered by thermal fluctuations and therefore might be of crucial importance in complex adaptive systems.
Get with the System: General Systems Theory for Business Officials.
Graczyk, Sandra L.
1993-01-01
An introduction to general systems theory and an overview of vocabulary and concepts are presented to introduce school business officials to systems thinking and to foster its use as an analytical tool. The theory is then used to analyze a sample problem: planning changes to a district's administrative computer system. (eight references) (MLF)
Educational Interpretations of General Systems Theory.
Hug, William E.; King, James E.
This chapter discusses General Systems Theory as it applies to education, classrooms, innovations, and instructional design. The principles of equifinality, open and closed systems, the individual as the key system, hierarchical structures, optimization, stability, cooperation, and competition are discussed, and their relationship to instructional…
Realization theory for rational systems
Ně mcová, J.; Schuppen, J.H. van
2008-01-01
In this paper we solve the problem of realization of response maps for rational systems. Sufficient and necessary conditions for a response map to be realizable by a rational system are presented. The properties of rational realizations such as observability, controllability, and minimality are stud
Stratified Medicine and Reimbursement Issues
Hans-Joerg eFugel
2012-10-01
Full Text Available Stratified Medicine (SM has the potential to target patient populations who will most benefit from a therapy while reducing unnecessary health interventions associated with side effects. The link between clinical biomarkers/diagnostics and therapies provides new opportunities for value creation to strengthen the value proposition to pricing and reimbursement (P&R authorities. However, the introduction of SM challenges current reimbursement schemes in many EU countries and the US as different P&R policies have been adopted for drugs and diagnostics. Also, there is a lack of a consistent process for value assessment of more complex diagnostics in these markets. New, innovative approaches and more flexible P&R systems are needed to reflect the added value of diagnostic tests and to stimulate investments in new technologies. Yet, the framework for access of diagnostic–based therapies still requires further development while setting the right incentives and appropriate align stakeholders interests when realizing long- term patient benefits. This article addresses the reimbursement challenges of SM approaches in several EU countries and the US outlining some options to overcome existing reimbursement barriers for stratified medicine.
General systems theory mathematical foundations
Mesarovic, Mihajlo D
1975-01-01
In this book, we study theoretical and practical aspects of computing methods for mathematical modelling of nonlinear systems. A number of computing techniques are considered, such as methods of operator approximation with any given accuracy; operator interpolation techniques including a non-Lagrange interpolation; methods of system representation subject to constraints associated with concepts of causality, memory and stationarity; methods of system representation with an accuracy that is the best within a given class of models; methods of covariance matrix estimation;methods for low-rank mat
Distributed computer systems theory and practice
Zedan, H S M
2014-01-01
Distributed Computer Systems: Theory and Practice is a collection of papers dealing with the design and implementation of operating systems, including distributed systems, such as the amoeba system, argus, Andrew, and grapevine. One paper discusses the concepts and notations for concurrent programming, particularly language notation used in computer programming, synchronization methods, and also compares three classes of languages. Another paper explains load balancing or load redistribution to improve system performance, namely, static balancing and adaptive load balancing. For program effici
Sampling Theory of Food Safety System
LI, Bing; Chen, Guohua; Zhu, Ning
2009-01-01
We introduce the stratified sampling method, and put forward theoretical unbiased estimation of stratified sampling program, as well as the model and statistics of experimental design test. We also discuss the establishment of dietary exposure model, pollutant distribution model, and risk evaluation model. Finally, we present some methods for sampling design in China.
Sampling Theory of Food Safety System
Li, Bing; Chen, Guohua; Zhu, Ning
2009-01-01
We introduce the stratified sampling method, and put forward theoretical unbiased estimation of stratified sampling program, as well as the model and statistics of experimental design test. We also discuss the establishment of dietary exposure model, pollutant distribution model, and risk evaluation model. Finally, we present some methods for sampling design in China.
The Theory of Random Laser Systems
Jiang, Xunya [Iowa State Univ., Ames, IA (United States)
2001-01-01
Studies of random laser systems are a new direction with promising potential applications and theoretical interest. The research is based on the theories of localization and laser physics. So far, the research shows that there are random lasing modes inside the systems which is quite different from the common laser systems. From the properties of the random lasing modes, they can understand the phenomena observed in the experiments, such as multi-peak and anisotropic spectrum, lasing mode number saturation, mode competition and dynamic processes, etc. To summarize, this dissertation has contributed the following in the study of random laser systems: (1) by comparing the Lamb theory with the Letokhov theory, the general formulas of the threshold length or gain of random laser systems were obtained; (2) they pointed out the vital weakness of previous time-independent methods in random laser research; (3) a new model which includes the FDTD method and the semi-classical laser theory. The solutions of this model provided an explanation of the experimental results of multi-peak and anisotropic emission spectra, predicted the saturation of lasing modes number and the length of localized lasing modes; (4) theoretical (Lamb theory) and numerical (FDTD and transfer-matrix calculation) studies of the origin of localized lasing modes in the random laser systems; and (5) proposal of using random lasing modes as a new path to study wave localization in random systems and prediction of the lasing threshold discontinuity at mobility edge.
Systems theory of interconnected port contact systems
Eberard, D.; Maschke, B.M.; Schaft, A.J. van der
2005-01-01
Port-based network modeling of a large class of complex physical systems leads to dynamical systems known as port-Hamiltonian systems. The key ingredient of any port-Hamiltonian system is a power-conserving interconnection structure (mathematically formalized by the geometric notion of a Dirac struc
Advanced Systems Theory Applied to AMB Systems
Balini, H.M.N.K.
2011-01-01
In this thesis we look at the application of advanced systems theoretic algorithms for an experimental Active Magnetic Bearing System (AMB). These systems are inherently unstable and therefore require a feedback controller. Accurate modeling of these systems with input-output data is hindered due to
Algebraic methods in system theory
Brockett, R. W.; Willems, J. C.; Willsky, A. S.
1975-01-01
Investigations on problems of the type which arise in the control of switched electrical networks are reported. The main results concern the algebraic structure and stochastic aspects of these systems. Future reports will contain more detailed applications of these results to engineering studies.
A novel classification system for aging theories
Lucas Siqueira Trindade
2013-03-01
Full Text Available Theories of lifespan evolution are a source of confusion amongst aging researchers. After a century of aging research the dispute over whether the aging process is active or passive persists and a comprehensive and universally accepted theoretical model remains elusive. Evolutionary aging theories primarily dispute whether the aging process is exclusively adapted to favor the kin or exclusively non-adapted to favor the individual. Interestingly, contradictory data and theories supporting both exclusively programmed and exclusively non-programmed theories continue to grow. However, this is a false dichotomy; natural selection favors traits resulting in efficient reproduction whether they benefit the individual or the kin. Thus, to understand the evolution of aging, first we must understand the environment-dependent balance between the advantages and disadvantages of extended lifespan in the process of spreading genes. As described by distinct theories, different niches and environmental conditions confer on extended lifespan a range of fitness values varying from highly beneficial to highly detrimental. Here, we considered the range of fitness values for extended lifespan and develop a fitness-based framework for categorizing existing theories. We show that all theories can be classified into four basic types: secondary (beneficial, maladaptive (neutral, assisted death (detrimental and senemorphic aging (varying between beneficial to detrimental. We anticipate that this classification system will assist with understanding and interpreting aging/death by providing a way of considering theories as members of one of these classes rather than consideration of their individual details.
Telecommunications system reliability engineering theory and practice
Ayers, Mark L
2012-01-01
"Increasing system complexity require new, more sophisticated tools for system modeling and metric calculation. Bringing the field up to date, this book provides telecommunications engineers with practical tools for analyzing, calculating, and reporting availability, reliability, and maintainability metrics. It gives the background in system reliability theory and covers in-depth applications in fiber optic networks, microwave networks, satellite networks, power systems, and facilities management. Computer programming tools for simulating the approaches presented, using the Matlab software suite, are also provided"
Optimization theory for large systems
Lasdon, Leon S
2011-01-01
Important text examines most significant algorithms for optimizing large systems and clarifying relations between optimization procedures. Much data appear as charts and graphs and will be highly valuable to readers in selecting a method and estimating computer time and cost in problem-solving. Initial chapter on linear and nonlinear programming presents all necessary background for subjects covered in rest of book. Second chapter illustrates how large-scale mathematical programs arise from real-world problems. Appendixes. List of Symbols.
Acoustic array systems theory, implementation, and application
Bai, Mingsian R; Benesty, Jacob
2013-01-01
Presents a unified framework of far-field and near-field array techniques for noise source identification and sound field visualization, from theory to application. Acoustic Array Systems: Theory, Implementation, and Application provides an overview of microphone array technology with applications in noise source identification and sound field visualization. In the comprehensive treatment of microphone arrays, the topics covered include an introduction to the theory, far-field and near-field array signal processing algorithms, practical implementations, and common applic
TRIZ theory in NEA photocathode preparation system
Qiao, Jianliang; Huang, Dayong; Li, Xiangjiang; Gao, Youtang
2016-09-01
The solutions to the engineering problems were provided according to the innovation principle based on the theory of TRIZ. The ultra high vacuum test and evaluation system for the preparation of negative electron affinity (NEA) photocathode has the characteristics of complex structure and powerful functions. Segmentation principle, advance function principle, curved surface principle, dynamic characteristics principle and nested principle adopted by the design of ultra high vacuum test and evaluation system for cathode preparation were analyzed. The applications of the physical contradiction and the substance-field analysis method of the theory of TRIZ in the cathode preparation ultra high vacuum test and evaluation system were discussed.
Rube Goldberg Salad System: Teaching Systems Theory in Communication
Linabary, Jasmine R.; Long, Ziyu; Mouton, Ashton; Rao, Ranjani L.; Buzzanell, Patrice M.
2016-01-01
Systems theory has been a staple in organizational communication textbooks since the field's inception (Miller, 2015; Poole, 2014). Nevertheless, the authors' classroom experiences have revealed that systems theory may not seem applicable to students due to its complicated nature. While examples and cases can help students make sense of the…
A Systems Perspective on World-Systems Theory.
Straussfogel, Debra
1997-01-01
Presents a conceptual framework that embeds ideas from world-systems theory within the larger context known as the theory of dissipative structures. This perspective reflects the interconnectedness of individual and separate places into a larger global system that is a single functioning spatial entity. (MJP)
Rube Goldberg Salad System: Teaching Systems Theory in Communication
Linabary, Jasmine R.; Long, Ziyu; Mouton, Ashton; Rao, Ranjani L.; Buzzanell, Patrice M.
2016-01-01
Systems theory has been a staple in organizational communication textbooks since the field's inception (Miller, 2015; Poole, 2014). Nevertheless, the authors' classroom experiences have revealed that systems theory may not seem applicable to students due to its complicated nature. While examples and cases can help students make sense of the…
BF topological theories and infinitely reducible systems
Caicedo, M I; Bol, S; Bol, Simon
1996-01-01
We present a rigurous disscusion for abelian BF theories in which the base manifold of the U(1) bundle is homeomorphic to a Hilbert space. The theory has an infinte number of stages of reducibility. We specify conditions on the base manifold under which the covarinat quantization of the system can be performed unambiguously. Applications of the formulation to the superparticle and the supertstring are also discussed.
Conformal invariance and Hamilton Jacobi theory for dissipative systems
Kiehn, R. M.
1975-01-01
For certain dissipative systems, a comparison can be made between the Hamilton-Jacobi theory and the conformal invariance of action theory. The two concepts are not identical, but the conformal action theory covers the Hamilton-Jacobi theory.
Suppression of stratified explosive interactions
Meeks, M.K.; Shamoun, B.I.; Bonazza, R.; Corradini, M.L. [Wisconsin Univ., Madison, WI (United States). Dept. of Nuclear Engineering and Engineering Physics
1998-01-01
Stratified Fuel-Coolant Interaction (FCI) experiments with Refrigerant-134a and water were performed in a large-scale system. Air was uniformly injected into the coolant pool to establish a pre-existing void which could suppress the explosion. Two competing effects due to the variation of the air flow rate seem to influence the intensity of the explosion in this geometrical configuration. At low flow rates, although the injected air increases the void fraction, the concurrent agitation and mixing increases the intensity of the interaction. At higher flow rates, the increase in void fraction tends to attenuate the propagated pressure wave generated by the explosion. Experimental results show a complete suppression of the vapor explosion at high rates of air injection, corresponding to an average void fraction of larger than 30%. (author)
Recommender Systems using Graph Theory
Vishal Venkatraman
2013-08-01
Full Text Available Recommender systems have become one of the important tools in E-Commerce. They combine the ratings of services or products by one user with the ratings from other users to answer similar interest queries with predictions and suggestions. The users thus receive anonymous recommendations from people similar interests. Even though this process seems unobjectionable, it aggregates user preferences, which can be tapped to recognise information about a particular user. Users who rate products or services across different types or domains in the systems are the major victims for this exploitation. We could determine the advantages and risks by performing a detailed analysis with a particular recommendation algorithm, but it would be difficult to draw general conclusions from this approach. In this paper, we aim for an algorithm independent analysis by applying a graph-theoretic model. By employing this model, we show that a user benefits most from recommendations based on similarity between the various products rated by the users. This paper tries to draw a graph through the various items rated by the users and finds the items that are most common among the user and his friends which is then recommended to him.
Dynamical Systems Theory: Application to Pedagogy
Abraham, Jane L.
Theories of learning affect how cognition is viewed, and this subsequently leads to the style of pedagogical practice that is used in education. Traditionally, educators have relied on a variety of theories on which to base pedagogy. Behavioral learning theories influenced the teaching/learning process for over 50 years. In the 1960s, the information processing approach brought the mind back into the learning process. The current emphasis on constructivism integrates the views of Piaget, Vygotsky, and cognitive psychology. Additionally, recent scientific advances have allowed researchers to shift attention to biological processes in cognition. The problem is that these theories do not provide an integrated approach to understanding principles responsible for differences among students in cognitive development and learning ability. Dynamical systems theory offers a unifying theoretical framework to explain the wider context in which learning takes place and the processes involved in individual learning. This paper describes how principles of Dynamic Systems Theory can be applied to cognitive processes of students, the classroom community, motivation to learn, and the teaching/learning dynamic giving educational psychologists a framework for research and pedagogy.
Toward A Practical General Systems Methodological Theory
Nagib Callaos; Belkis Sánchez de Callaos
2003-01-01
Our main purpose in this paper is to describe the way in which we have been relating General System Theory (GST) to practice and to the design of a General Systems Methodology (GSM). Our first step was to apply GST to design a methodology for software development. Then, in a second step, by means of the experience/knowledge learned from applying the methodology to developing specific information systems, a continuous designing and re-designing process started, which simultaneously generalized...
Using institutional theory in enterprise systems research
Svejvig, Per
2013-01-01
This paper sets out to examine the use of institutional theory as a conceptually rich lens to study social issues of enterprise systems (ES) research. More precisely, the purpose is to categorize current ES research using institutional theory to develop a conceptual model that advances ES research....... Key institutional features are presented such as isomorphism, rationalized myths, and bridging macro and micro structures, and institutional logics and their implications for ES research are discussed. Through a literature review of 181 articles, of which 18 papers are selected, we build a conceptual...... model that advocates multi-level and multi-theory approaches and applies newer institutional aspects such as institutional logics. The findings show that institutional theory in ES research is in its infancy and adopts mainly traditional institutional aspects like isomorphism, with the organization...
Critical Point Theory for Lagrangian Systems
Mazzucchelli, Marco
2012-01-01
Lagrangian systems constitute a very important and old class in dynamics. Their origin dates back to the end of the eighteenth century, with Joseph-Louis Lagrange's reformulation of classical mechanics. The main feature of Lagrangian dynamics is its variational flavor: orbits are extremal points of an action functional. The development of critical point theory in the twentieth century provided a powerful machinery to investigate existence and multiplicity questions for orbits of Lagrangian systems. This monograph gives a modern account of the application of critical point theory, and more spec
[Systems theory in medicine and biology].
Feigl, W; Bonet, E M
1989-03-15
We try to determinate, that systems theory has to be introduced into modern medicine. The biological roots as well as the cybernetic ones are outlined. Among various concepts about systems theory the evaluation by Riedl seems to be the most efficient to explain medical procedures. His basic informations refer to von Bertalanffy, the additional introduction of a 4-cause-principle, Aristoteles, permits the explanation of complex relations. The examples of tumor and inflammation are used to demonstrate the basic idea of the formal cause as well as the final cause. The latter should also become an important fact in the solution of other medical problems.
Eleven theses of general systems theory (GST)
Waelchli, F. [Defense Systems Management College, Fort Belvoir, VA (United States)
1992-12-31
This paper chronicles an effort to distill and order (for purposes of discussion and elaboration) frequently mentioned and significant ideas encountered in the literature of General Systems theory (GST). The product is a set of eleven theses, representing the author`s selection and collation of seminal and recurrent GST themes. The author argues that attention to theory could aid the effort to develop practical applications of systems thinking. (Remember that a thesis is a statement or assertion, offered originally without proof, as the basis for an argument, discussion, or empirical test). 10 refs.
Mathematical System Theory and System Modeling
1980-01-01
Choosing models related effectively to the questions to be addressed is a central issue in the craft of systems analysis. Since the mathematical description the analyst chooses constrains the types of issues he candeal with, it is important for these models to be selected so as to yield limitations that are acceptable in view of the questions the systems analysis seeks to answer. In this paper, the author gives an overview of the central issues affecting the question of model choice. To ...
The Theory of Random Laser Systems
Xun Ya Jian
2002-01-01
Studies of random laser systems are a new direction with promising potential applications and theoretical interest. The research is based on the theories of localization and laser physics. So far, the research shows that there are random lasing modes inside the systems which is quite different from the common laser systems. From the properties of the random lasing modes, they can understand the phenomena observed in the experiments, such as multi-peak and anisotropic spectrum, lasing mode number saturation, mode competition and dynamic processes, etc. To summarize, this dissertation has contributed the following in the study of random laser systems: (1) by comparing the Lamb theory with the Letokhov theory, the general formulas of the threshold length or gain of random laser systems were obtained; (2) they pointed out the vital weakness of previous time-independent methods in random laser research; (3) a new model which includes the FDTD method and the semi-classical laser theory. The solutions of this model ...
Topological theory of dynamical systems recent advances
Aoki, N
1994-01-01
This monograph aims to provide an advanced account of some aspects of dynamical systems in the framework of general topology, and is intended for use by interested graduate students and working mathematicians. Although some of the topics discussed are relatively new, others are not: this book is not a collection of research papers, but a textbook to present recent developments of the theory that could be the foundations for future developments. This book contains a new theory developed by the authors to deal with problems occurring in diffentiable dynamics that are within the scope of general topology. To follow it, the book provides an adequate foundation for topological theory of dynamical systems, and contains tools which are sufficiently powerful throughout the book. Graduate students (and some undergraduates) with sufficient knowledge of basic general topology, basic topological dynamics, and basic algebraic topology will find little difficulty in reading this book.
Nitrogen transformations in stratified aquatic microbial ecosystems
Revsbech, Niels Peter; Risgaard-Petersen, N.; Schramm, Andreas
2006-01-01
Abstract New analytical methods such as advanced molecular techniques and microsensors have resulted in new insights about how nitrogen transformations in stratified microbial systems such as sediments and biofilms are regulated at a µm-mm scale. A large and ever-expanding knowledge base about n...
Theory and Simulation of Multicomponent Osmotic Systems.
Karunaweera, Sadish; Gee, Moon Bae; Weerasinghe, Samantha; Smith, Paul E
2012-05-28
Most cellular processes occur in systems containing a variety of components many of which are open to material exchange. However, computer simulations of biological systems are almost exclusively performed in systems closed to material exchange. In principle, the behavior of biomolecules in open and closed systems will be different. Here, we provide a rigorous framework for the analysis of experimental and simulation data concerning open and closed multicomponent systems using the Kirkwood-Buff (KB) theory of solutions. The results are illustrated using computer simulations for various concentrations of the solutes Gly, Gly(2) and Gly(3) in both open and closed systems, and in the absence or presence of NaCl as a cosolvent. In addition, KB theory is used to help rationalize the aggregation properties of the solutes. Here one observes that the picture of solute association described by the KB integrals, which are directly related to the solution thermodynamics, and that provided by more physical clustering approaches are different. It is argued that the combination of KB theory and simulation data provides a simple and powerful tool for the analysis of complex multicomponent open and closed systems.
Song, Y.; Moriyoshi, Y.; Wada, Y. [Chiba University, Chiba (Japan); Muroki, T. [Kanagawa Institute of Technology, Kanagawa (Japan)
1998-05-25
A pilot flame ignition system, which has superior characteristics in the high ignition energy and the large flame contact area to a conventional spark ignition system, is experimentally examined by the indicated pressure analysis and the high speed direct photography. A model combustion chamber, which simulates a Wankel-type direct injection stratified charge rotary engine, was employed to test the ignition performance of both the pilot flame ignition and spark ignition systems. As a result, it was found that the pilot flame system successfully ignites the very lean charge stratified mixture which the spark system fails to ignite and that the combustion characteristic difference using different ignition systems becomes small as the overall equivalence ratio is increased. 6 refs., 15 figs., 2 tabs.
General Systems Theory and Counterplan Competition.
Madsen, Arnie
1989-01-01
Discusses the trend in academic debate on policy questions toward a wide acceptance of counterplans, encouraging combinations of proposals which appear at face value able to coexist but upon deeper analysis are incompatible. Argues in opposition to this trend by applying concepts from general systems theory to competition. (KEH)
Possibilistic systems within a general information theory
Joslyn, C.
1999-06-01
The author surveys possibilistic systems theory and place it in the context of Imprecise Probabilities and General Information Theory (GIT). In particular, he argues that possibilistic systems hold a distinct position within a broadly conceived, synthetic GIT. The focus is on systems and applications which are semantically grounded by empirical measurement methods (statistical counting), rather than epistemic or subjective knowledge elicitation or assessment methods. Regarding fuzzy measures as special provisions, and evidence measures (belief and plausibility measures) as special fuzzy measures, thereby he can measure imprecise probabilities directly and empirically from set-valued frequencies (random set measurement). More specifically, measurements of random intervals yield empirical fuzzy intervals. In the random set (Dempster-Shafer) context, probability and possibility measures stand as special plausibility measures in that their distributionality (decomposability) maps directly to an aggregable structure of the focal classes of their random sets. Further, possibility measures share with imprecise probabilities the ability to better handle open world problems where the universe of discourse is not specified in advance. In addition to empirically grounded measurement methods, possibility theory also provides another crucial component of a full systems theory, namely prediction methods in the form of finite (Markov) processes which are also strictly analogous to the probabilistic forms.
Intersubjective systems theory: a fallibilist's journey.
Orange, Donna M
2009-04-01
Intersubjective systems theory is the view that personal experience always emerges, maintains itself, and transforms in relational contexts. It is held for reasons of personal inclinations, philosophical belief, and clinical conviction. As a clinical sensibility, it primarily includes an emphasis on the emotional convictions or organizing principles that systematize experience, the personal engagement of the analyst, and the refusal to argue about reality.
Pathways, Networks, and Systems: Theory and Experiments
Joseph H. Nadeau; John D. Lambris
2004-10-30
The international conference provided a unique opportunity for theoreticians and experimenters to exchange ideas, strategies, problems, challenges, language and opportunities in both formal and informal settings. This dialog is an important step towards developing a deep and effective integration of theory and experiments in studies of systems biology in humans and model organisms.
A theory of desynchronisable closed loop system
Harsh Beohar
2010-10-01
Full Text Available The task of implementing a supervisory controller is non-trivial, even though different theories exist that allow automatic synthesis of these controllers in the form of automata. One of the reasons for this discord is due to the asynchronous interaction between a plant and its controller in implementations, whereas the existing supervisory control theories assume synchronous interaction. As a consequence the implementation suffer from the so-called inexact synchronisation problem. In this paper we address the issue of inexact synchronisation in a process algebraic setting, by solving a more general problem of refinement. We construct an asynchronous closed loop system by introducing a communication medium in a given synchronous closed loop system. Our goal is to find sufficient conditions under which a synchronous closed loop system is branching bisimilar to its corresponding asynchronous closed loop system.
Simulation model of stratified thermal energy storage tank using finite difference method
Waluyo, Joko
2016-06-01
Stratified TES tank is normally used in the cogeneration plant. The stratified TES tanks are simple, low cost, and equal or superior in thermal performance. The advantage of TES tank is that it enables shifting of energy usage from off-peak demand for on-peak demand requirement. To increase energy utilization in a stratified TES tank, it is required to build a simulation model which capable to simulate the charging phenomenon in the stratified TES tank precisely. This paper is aimed to develop a novel model in addressing the aforementioned problem. The model incorporated chiller into the charging of stratified TES tank system in a closed system. The model was developed in one-dimensional type involve with heat transfer aspect. The model covers the main factors affect to degradation of temperature distribution namely conduction through the tank wall, conduction between cool and warm water, mixing effect on the initial flow of the charging as well as heat loss to surrounding. The simulation model is developed based on finite difference method utilizing buffer concept theory and solved in explicit method. Validation of the simulation model is carried out using observed data obtained from operating stratified TES tank in cogeneration plant. The temperature distribution of the model capable of representing S-curve pattern as well as simulating decreased charging temperature after reaching full condition. The coefficient of determination values between the observed data and model obtained higher than 0.88. Meaning that the model has capability in simulating the charging phenomenon in the stratified TES tank. The model is not only capable of generating temperature distribution but also can be enhanced for representing transient condition during the charging of stratified TES tank. This successful model can be addressed for solving the limitation temperature occurs in charging of the stratified TES tank with the absorption chiller. Further, the stratified TES tank can be
Symmetric linear systems - An application of algebraic systems theory
Hazewinkel, M.; Martin, C.
1983-01-01
Dynamical systems which contain several identical subsystems occur in a variety of applications ranging from command and control systems and discretization of partial differential equations, to the stability augmentation of pairs of helicopters lifting a large mass. Linear models for such systems display certain obvious symmetries. In this paper, we discuss how these symmetries can be incorporated into a mathematical model that utilizes the modern theory of algebraic systems. Such systems are inherently related to the representation theory of algebras over fields. We will show that any control scheme which respects the dynamical structure either implicitly or explicitly uses the underlying algebra.
Symmetric linear systems - An application of algebraic systems theory
Hazewinkel, M.; Martin, C.
1983-01-01
Dynamical systems which contain several identical subsystems occur in a variety of applications ranging from command and control systems and discretization of partial differential equations, to the stability augmentation of pairs of helicopters lifting a large mass. Linear models for such systems display certain obvious symmetries. In this paper, we discuss how these symmetries can be incorporated into a mathematical model that utilizes the modern theory of algebraic systems. Such systems are inherently related to the representation theory of algebras over fields. We will show that any control scheme which respects the dynamical structure either implicitly or explicitly uses the underlying algebra.
Amin Douillet, Guilhem; Peltier, Aline; Finizola, Anthony; Brothelande, Elodie; Garaebiti, Esline
2014-05-01
Subsurface thermal measurements provide a valuable tool to map hydrothermal-fluid release zones in activevolcanic areas. On explosive volcanoes, where ash fall layers deposit parallel to the ground surface, hydrothermal fluids are trapped in the stratification due to the variations in permeability in deposits of the different explosive phases. Thermal fluids thus travel parallel to the surface close to the ground. This horizontal flux can only escape when faults break the seals of stratification. On the Yasur-Yenkahe volcanic complex (Tanna Island, Vanuatu archipelago), fumaroles andhot springs abound, signs of upraising heat fluxes associated to a well-developed hydrothermal activity. Combinationof high resolution mapping of ground thermal anomalies with geomorphological analysis allows thecharacterization of the structural relationships between the active Yasur volcano and the Yenkahe resurgent dome. A complex system of heat release and hydrothermal fluid circulation below the Yasur-Yenkahe complex isevidenced. Circulation, though propagating vertically as a whole, is funneled by stratification. Thus, the main thermal fluid release is almost exclusively concentrated along structural limits that break the seals inducedby the stratified nature of the ground. Three types of medium/high temperature anomalies have beenevidenced: (1) broad hydrothermalized areas linked with planar stratification that favor lateral spreading,(2) linear segments that represent active faults, and (3) arcuate segments related to paleo-crater rims. Thelimit between the Yasur volcano and the Yenkahe resurgent dome is characterized by an active fault systemaccommodating both the rapid uplift of the Yenkahe block and the overloading induced by the volcanoweight. In such a setting, faults converge below the cone of Yasur, which acts as a focus for the faults. Evidenceof such structures, sometimes hidden in the landscape but detected by thermal measurements, iscritical for risk assessment of
Identification of dynamic systems, theory and formulation
Maine, R. E.; Iliff, K. W.
1985-01-01
The problem of estimating parameters of dynamic systems is addressed in order to present the theoretical basis of system identification and parameter estimation in a manner that is complete and rigorous, yet understandable with minimal prerequisites. Maximum likelihood and related estimators are highlighted. The approach used requires familiarity with calculus, linear algebra, and probability, but does not require knowledge of stochastic processes or functional analysis. The treatment emphasizes unification of the various areas in estimation in dynamic systems is treated as a direct outgrowth of the static system theory. Topics covered include basic concepts and definitions; numerical optimization methods; probability; statistical estimators; estimation in static systems; stochastic processes; state estimation in dynamic systems; output error, filter error, and equation error methods of parameter estimation in dynamic systems, and the accuracy of the estimates.
Open quantum systems and Random Matrix Theory
Mulhall, Declan
2014-01-01
A simple model for open quantum systems is analyzed with Random Matrix Theory. The system is coupled to the continuum in a minimal way. In this paper we see the effect of opening the system on the level statistics, in particular the $\\Delta_3(L)$ statistic, width distribution and level spacing are examined as a function of the strength of this coupling. A super-radiant transition is observed, and it is seen that as it is formed, the level spacing and $\\Delta_3(L)$ statistic exhibit the signatures of missed levels.
Open quantum systems and random matrix theory
Mulhall, Declan
2015-01-01
A simple model for open quantum systems is analyzed with random matrix theory. The system is coupled to the continuum in a minimal way. In this paper the effect on the level statistics of opening the system is seen. In particular the Δ3(L ) statistic, the width distribution and the level spacing are examined as a function of the strength of this coupling. The emergence of a super-radiant transition is observed. The level spacing and Δ3(L ) statistics exhibit the signatures of missed levels or intruder levels as the super-radiant state is formed.
Sandler, Martin [EFG Energie fuer Gebaeude e.K., Kaufbeuren (Germany)
2011-05-15
The interaction of all components of solar systems must be right. A decisive factor is that unnecessary heat is stored precisely in order to provide the heat immediately and completely to the user. This can be accomplished with a well-functioning stratified reservoir. From this perspective, the author of the contribution under consideration reports on an investigation of the performance of solar combi-systems using high-resolution thermal imaging cameras.
Monotone random systems theory and applications
Chueshov, Igor
2002-01-01
The aim of this book is to present a recently developed approach suitable for investigating a variety of qualitative aspects of order-preserving random dynamical systems and to give the background for further development of the theory. The main objects considered are equilibria and attractors. The effectiveness of this approach is demonstrated by analysing the long-time behaviour of some classes of random and stochastic ordinary differential equations which arise in many applications.
Do citation systems represent theories of truth?
Betsy Van der Veer Martens
2001-01-01
Full Text Available This article suggests that the citation can be viewed not only as a "concept symbol" but also as a "boundary object". The scientific, legal, and patent citation systems in America are examined at the micro, meso, and macro levels in order to understand how they function as commodified theories of truth in contemporary knowledge representation. This approach also offers a meta-theoretical overview of existing citation research efforts in science, law, and technology that may be of interdisciplinary interest.
Dynamical Systems On Weighted Lattices: General Theory
Maragos, Petros
2016-01-01
In this work a theory is developed for unifying large classes of nonlinear discrete-time dy- namical systems obeying a superposition of a weighted maximum or minimum type. The state vectors and input-output signals evolve on nonlinear spaces which we call complete weighted lat- tices and include as special cases the nonlinear vector spaces of minimax algebra. Their algebraic structure has a polygonal geometry. Some of the special cases unified include max-plus, max- product, and probabilistic...
Dynamical systems theory for music dynamics
Boon, J P
1994-01-01
Abstract:We show that, when music pieces are cast in the form of time series of pitch variations, the concepts and tools of dynamical systems theory can be applied to the analysis of {\\it temporal dynamics} in music. (i) Phase space portraits are constructed from the time series wherefrom the dimensionality is evaluated as a measure of the {\\pit global} dynamics of each piece. (ii) Spectral analysis of the time series yields power spectra (\\sim f^{-\
Random matrix theory, interacting particle systems and integrable systems
Forrester, Peter
2014-01-01
Random matrix theory is at the intersection of linear algebra, probability theory and integrable systems, and has a wide range of applications in physics, engineering, multivariate statistics and beyond. This volume is based on a Fall 2010 MSRI program which generated the solution of long-standing questions on universalities of Wigner matrices and beta-ensembles and opened new research directions especially in relation to the KPZ universality class of interacting particle systems and low-rank perturbations. The book contains review articles and research contributions on all these topics, in addition to other core aspects of random matrix theory such as integrability and free probability theory. It will give both established and new researchers insights into the most recent advances in the field and the connections among many subfields.
System theory as applied differential geometry. [linear system
Hermann, R.
1979-01-01
The invariants of input-output systems under the action of the feedback group was examined. The approach used the theory of Lie groups and concepts of modern differential geometry, and illustrated how the latter provides a basis for the discussion of the analytic structure of systems. Finite dimensional linear systems in a single independent variable are considered. Lessons of more general situations (e.g., distributed parameter and multidimensional systems) which are increasingly encountered as technology advances are presented.
Theory and design of CNC systems
Suh, Suk-Hwan; Chung, Dae-Hyuk; Stroud, Ian
2008-01-01
Computer Numerical Control (CNC) controllers are high value-added products counting for over 30% of the price of machine tools. The development of CNC technology depends on the integration of technologies from many different industries, and requires strategic long-term support. a oeTheory and Design of CNC Systemsa covers the elements of control, the design of control systems, and modern open-architecture control systems. Topics covered include Numerical Control Kernel (NCK) design of CNC, Programmable Logic Control (PLC), and the Man-Machine Interface (MMI), as well as the major modules for t
Quantum information theory with Gaussian systems
Krueger, O.
2006-04-06
This thesis applies ideas and concepts from quantum information theory to systems of continuous-variables such as the quantum harmonic oscillator. The focus is on three topics: the cloning of coherent states, Gaussian quantum cellular automata and Gaussian private channels. Cloning was investigated both for finite-dimensional and for continuous-variable systems. We construct a private quantum channel for the sequential encryption of coherent states with a classical key, where the key elements have finite precision. For the case of independent one-mode input states, we explicitly estimate this precision, i.e. the number of key bits needed per input state, in terms of these parameters. (orig.)
Engineering System Theory--A New Engineering Meta-Discipline
无
1999-01-01
This paper proposes a new engineering discipline--Engineering System Theory. It discusses rendered background, research objects and contents of the engineering system theory briefly. Finally, the meta-discipline standing of the engineering system theory in the whole knowledge system of engineering science and its development potential are pointed out.
Scattering theory for open quantum systems
Behrndt, Jussi [Technische Univ. Berlin (Germany). Inst. fuer Mathematik; Malamud, Mark M. [Donetsk National University (Ukraine). Dept. of Mathematics; Neidhardt, Hagen [Weierstrass-Institut fuer Angewandte Analysis und Stochastik (WIAS) im Forschungsverbund Berlin e.V. (Germany)
2006-07-01
Quantum systems which interact with their environment are often modeled by maximal dissipative operators or so-called Pseudo-Hamiltonians. In this paper the scattering theory for such open systems is considered. First it is assumed that a single maximal dissipative operator A{sub D} in a Hilbert space H is used to describe an open quantum system. In this case the minimal self-adjoint dilation K of A{sub D} can be regarded as the Hamiltonian of a closed system which contains the open system {l_brace}A{sub D},h{r_brace}, but since K is necessarily not semibounded from below, this model is difficult to interpret from a physical point of view. In the second part of the paper an open quantum system is modeled with a family {l_brace}A({mu}){r_brace} of maximal dissipative operators depending on energy {mu}, and it is shown that the open system can be embedded into a closed system where the Hamiltonian is semibounded. Surprisingly it turns out that the corresponding scattering matrix can be completely recovered from scattering matrices of single Pseudo-Hamiltonians as in the first part of the paper. The general results are applied to a class of Sturm-Liouville operators arising in dissipative and quantum transmitting Schroedinger-Poisson systems. (orig.)
Systems biology: the reincarnation of systems theory applied in biology?
Wolkenhauer, O
2001-09-01
With the availability of quantitative data on the transcriptome and proteome level, there is an increasing interest in formal mathematical models of gene expression and regulation. International conferences, research institutes and research groups concerned with systems biology have appeared in recent years and systems theory, the study of organisation and behaviour per se, is indeed a natural conceptual framework for such a task. This is, however, not the first time that systems theory has been applied in modelling cellular processes. Notably in the 1960s systems theory and biology enjoyed considerable interest among eminent scientists, mathematicians and engineers. Why did these early attempts vanish from research agendas? Here we shall review the domain of systems theory, its application to biology and the lessons that can be learned from the work of Robert Rosen. Rosen emerged from the early developments in the 1960s as a main critic but also developed a new alternative perspective to living systems, a concept that deserves a fresh look in the post-genome era of bioinformatics.
Electromagnetic waves in stratified media
Wait, James R; Fock, V A; Wait, J R
2013-01-01
International Series of Monographs in Electromagnetic Waves, Volume 3: Electromagnetic Waves in Stratified Media provides information pertinent to the electromagnetic waves in media whose properties differ in one particular direction. This book discusses the important feature of the waves that enables communications at global distances. Organized into 13 chapters, this volume begins with an overview of the general analysis for the electromagnetic response of a plane stratified medium comprising of any number of parallel homogeneous layers. This text then explains the reflection of electromagne
Levels of Analysis in Systems Theories of Personality.
Lester, David
1986-01-01
Systems theories of personality often describe subsystems (such as conscious and unconscious) and subsubsystems (such as ego, id, and superego). This paper classifies the major systems theories of personality in terms of the number of levels in their analysis. (Author)
Rate-independent systems theory and application
Mielke, Alexander
2015-01-01
This monograph provides both an introduction to and a thorough exposition of the theory of rate-independent systems, which the authors have worked on with a number of collaborators over many years. The focus is mostly on fully rate-independent systems, first on an abstract level with or without a linear structure, discussing various concepts of solutions with full mathematical rigor. The usefulness of the abstract concepts is then demonstrated on the level of various applications primarily in continuum mechanics of solids, including suitable approximation strategies with guaranteed numerical stability and convergence. Particular applications concern inelastic processes such as plasticity, damage, phase transformations, or adhesive-type contacts both at small strains and at finite strains. Other physical systems such as magnetic or ferroelectric materials, and couplings to rate-dependent thermodynamic models are also considered. Selected applications are accompanied by numerical simulations illustrating both t...
Theory of uniqueness of Indian Caste System
Ashwin Kumar
2006-08-01
Full Text Available Classical studies on pre-modern Indian social structure have suggested apparent differences between the Indian caste system and social stratification as one can discern in other parts of the world. However, one needs to question such dogmatic assertions that such vast differences really existed. An endeavor is made in this research paper to reflect on the nature of caste hierarchy in pre-modern India. The caste system forms the significant basis of pre-modern Indian social structure. Early writers conceived the caste system of pre-modern India as something unique to India. An attempt is made to question this application of theory of uniqueness in the case of India.
Theory of uniqueness of Indian Caste System
Ashwin Kumar
2005-11-01
Full Text Available Classical studies on pre-modern Indian social structure have suggested apparent differences between the Indian caste system and social stratification as one can discern in other parts of the world. However, one needs to question such dogmatic assertions that such vast differences really existed. An endeavor is made in this research paper to reflect on the nature of caste hierarchy in pre-modern India. The caste system forms the significant basis of pre-modern Indian social structure. Early writers conceived the caste system of pre-modern India as something unique to India. An attempt is made to question this application of theory of uniqueness in the case of India.
Applied optimal control theory of distributed systems
Lurie, K A
1993-01-01
This book represents an extended and substantially revised version of my earlierbook, Optimal Control in Problems ofMathematical Physics,originally published in Russian in 1975. About 60% of the text has been completely revised and major additions have been included which have produced a practically new text. My aim was to modernize the presentation but also to preserve the original results, some of which are little known to a Western reader. The idea of composites, which is the core of the modern theory of optimization, was initiated in the early seventies. The reader will find here its implementation in the problem of optimal conductivity distribution in an MHD-generatorchannel flow.Sincethen it has emergedinto an extensive theory which is undergoing a continuous development. The book does not pretend to be a textbook, neither does it offer a systematic presentation of the theory. Rather, it reflects a concept which I consider as fundamental in the modern approach to optimization of dis tributed systems. ...
An application of Bowen family systems theory.
Haefner, Judy
2014-11-01
While nurse practitioners initially work with the identified patient, Murray Bowen maintains it is the reciprocal functioning of all the members of the family which contributes to the emotional intensity of the patient. The emotional symptoms of an individual are an expression of the emotional symptoms of the family, which are often embedded in patterns of behaviors from past generations. The purpose of this paper is to facilitate understanding Bowen's theoretical concepts of family systems theory and apply these concepts to a family in therapy.
The fully nonlinear stratified geostrophic adjustment problem
Coutino, Aaron; Stastna, Marek
2017-01-01
The study of the adjustment to equilibrium by a stratified fluid in a rotating reference frame is a classical problem in geophysical fluid dynamics. We consider the fully nonlinear, stratified adjustment problem from a numerical point of view. We present results of smoothed dam break simulations based on experiments in the published literature, with a focus on both the wave trains that propagate away from the nascent geostrophic state and the geostrophic state itself. We demonstrate that for Rossby numbers in excess of roughly 2 the wave train cannot be interpreted in terms of linear theory. This wave train consists of a leading solitary-like packet and a trailing tail of dispersive waves. However, it is found that the leading wave packet never completely separates from the trailing tail. Somewhat surprisingly, the inertial oscillations associated with the geostrophic state exhibit evidence of nonlinearity even when the Rossby number falls below 1. We vary the width of the initial disturbance and the rotation rate so as to keep the Rossby number fixed, and find that while the qualitative response remains consistent, the Froude number varies, and these variations are manifested in the form of the emanating wave train. For wider initial disturbances we find clear evidence of a wave train that initially propagates toward the near wall, reflects, and propagates away from the geostrophic state behind the leading wave train. We compare kinetic energy inside and outside of the geostrophic state, finding that for long times a Rossby number of around one-quarter yields an equal split between the two, with lower (higher) Rossby numbers yielding more energy in the geostrophic state (wave train). Finally we compare the energetics of the geostrophic state as the Rossby number varies, finding long-lived inertial oscillations in the majority of the cases and a general agreement with the past literature that employed either hydrostatic, shallow-water equation-based theory or
Stratified medicine and reimbursement issues
Fugel, Hans-Joerg; Nuijten, Mark; Postma, Maarten
2012-01-01
Stratified Medicine (SM) has the potential to target patient populations who will most benefit from a therapy while reducing unnecessary health interventions associated with side effects. The link between clinical biomarkers/diagnostics and therapies provides new opportunities for value creation to
Theories and simulations of complex social systems
Mago, Vijay
2014-01-01
Research into social systems is challenging due to their complex nature. Traditional methods of analysis are often difficult to apply effectively as theories evolve over time. This can be due to a lack of appropriate data, or too much uncertainty. It can also be the result of problems which are not yet understood well enough in the general sense so that they can be classified, and an appropriate solution quickly identified. Simulation is one tool that deals well with these challenges, fits in well with the deductive process, and is useful for testing theory. This field is still relatively new, and much of the work is necessarily innovative, although it builds upon a rich and varied foundation. There are a number of existing modelling paradigms being applied to complex social systems research. Additionally, new methods and measures are being devised through the process of conducting research. We expect that readers will enjoy the collection of high quality research works from new and accomplished researchers. ...
Inelastic transport theory for nanoscale systems
Frederiksen, Thomas
2007-01-01
This thesis describes theoretical and numerical investigations of inelastic scat- tering and energy dissipation in electron transport through nanoscale sys- tems. A computational scheme, based on a combination of density functional theory (DFT) and nonequilibrium Green’s functions (NEGF), has been...... the conductance. The methods have been applied to a number of specific systems, includ- ing monatomic gold chains, atomic point contacts, and metal-molecule-metal configurations. These studies have clarified the inelastic effects in the elec- tron transport and characterized the vibrational modes that couple...... to the current. For instance, the dominant scattering for gold chains could be traced back to the longitudinal “alternating bond-length” mode. Furthermore, the results have been compared critically with experimental measurements for the different systems, and provided a microscopic understanding for the im...
Theory and Simulations of Solar System Plasmas
Goldstein, Melvyn L.
2011-01-01
"Theory and simulations of solar system plasmas" aims to highlight results from microscopic to global scales, achieved by theoretical investigations and numerical simulations of the plasma dynamics in the solar system. The theoretical approach must allow evidencing the universality of the phenomena being considered, whatever the region is where their role is studied; at the Sun, in the solar corona, in the interplanetary space or in planetary magnetospheres. All possible theoretical issues concerning plasma dynamics are welcome, especially those using numerical models and simulations, since these tools are mandatory whenever analytical treatments fail, in particular when complex nonlinear phenomena are at work. Comparative studies for ongoing missions like Cassini, Cluster, Demeter, Stereo, Wind, SDO, Hinode, as well as those preparing future missions and proposals, like, e.g., MMS and Solar Orbiter, are especially encouraged.
Multimedia and Internet Systems Theory and Practice
Choroś, Kazimierz; Siemiński, Andrzej
2013-01-01
Aleksander Zgrzywa, Kazimierz Choroś, and Andrzej Siemiński (Eds.) Multimedia and Internet Systems: Theory and Practice During the last 20 years we have witnessed a rapid development of Multimedia and Network Information Systems. What is even more important, the pace of change does not show any sign of slowing. When we look back we see how many research projects that have originated at various universities or in research facilities are now part of our everyday life. This monograph offers the reader a very broad review of the most recent scientific investigations in that area. The book is a collection of carefully selected and the most representative investigations, solutions, and applications presented by scientific teams from several countries. The content of the monograph has been divided into four parts: 1. Multimedia Information Technology 2. Information Systems Specification 3. Information Systems Applications 4. Web Systems and Network Technologies The book is aiming to attract more ...
General systems theory: implications for theory and action in occupational therapy.
Kielhofner, G
1978-11-01
This paper presents a description of the transformation of science under General Systems Theory, and the relationship of this transformation to the field of occupational therapy. Changes in scientific methods of proof and in scientific laws that underlie theory are discussed. The paper presents a scale for recognizing complexity in phenomena and for analyzing the appropriateness of theories designed to explain the phenomena. It also presents the theory of open systems as an alternative to mechanistic explanations of human behavior.
Condensation theory for finite, closed systems
Donoghue, Edward; Gibbs, Julian H.
1981-03-01
The applicability of Mayer's cluster integral formulation of statistical mechanics in the canonical ensemble has been restricted to the gas phase by two difficulties: the enormous labor required for the calculation of cluster integrals from realistic intermolecular potentials and the divergence of the cluster integral expansions of thermodynamic observables and n-particle correlation functions prior to condensation. In this paper the divergence of the cluster expansions is shown to be due to the way in which the limit of a system of infinite size is taken, implicitly, when the partition function, written as a sum over all the cluster size distributions attainable by the closed system, is approximated by its maximum term alone. The use in condensation theory of this ''maximum term approximation,'' and of the particular infinite limit it entails, are obviated herein by demonstration that the full theory with use of all the terms in the partition function, can be solved conveniently and exactly by recurrence relation (or formal power series) methods. The cluster size distributions thus found, since they describe finite systems, can have no associated divergences. Because no realistic set of volume dependent cluster integrals is known, we demonstrate the new formalism and the use of the recurrence relations in the case of cluster integrals obtained in the infinite volume limit from the virial expansion determined by the van der Waals equation of state. At low densities these are seen to predict correctly the ideal, imperfect, and metastable states of the homogeneous gas phase. Beyond the spinodal density, they predict bimodal cluster size distributions distinctive of coexisting vapor and liquid; the corresponding pressure isotherms are found to be constant, rather than diverging or displaying a van der Waals loop. Because the sole approximation made is the replacement of the volume dependent cluster integrals by their infinite volume limits, this evidently is the cause
A historical approach to the general theory of systems
Esther María Pino Guzmán
2015-01-01
Full Text Available The paper is intended to examine the epistemological development of the theory or systems, focus the change of its scientific paradigm and points out its main implications for the development of research methodology and design. The theoretical methods being used makes possible to go deeper into the analysis of regularities and essential qualities in the construction and development of the scientific theory. The system approach is one of the most frequently used method and the one of further reaching effect in Pedagogy. The system approach or systemic thinking is a requirement for the general direction of pedagogy problem studies. This paper explores the ways of interconnecting the theory of systems to the theory of complexity in the field of pedagogy. The findings include a historical approach to the theory of systems up to the spring up of the theory of complexity. Key words: general theory of systems, interdisciplinary relations, complexity.
Global positioning system theory and practice
Hofmann-Wellenhof, Bernhard; Collins, James
2001-01-01
This book is dedicated to Dr. Benjamin William Remondi for many reasons. The project of writing a Global Positioning System (GPS) book was con ceived in April 1988 at a GPS meeting in Darmstadt, Germany. Dr. Remondi discussed with me the need for an additional GPS textbook and suggested a possible joint effort. In 1989, I was willing to commit myself to such a project. Unfortunately, the timing was less than ideal for Dr. Remondi. Therefore, I decided to start the project with other coauthors. Dr. Remondi agreed and indicated his willingness to be a reviewer. I selected Dr. Herbert Lichtenegger, my colleague from the Technical University Graz, Austria, and Dr. James Collins from Rockville, Maryland, U.S.A. In my opinion, the knowledge ofthe three authors should cover the wide spectrum of GPS. Dr. Lichtenegger is a geodesist with broad experience in both theory and practice. He has specialized his research to geodetic astron omy including orbital theory and geodynamical phenomena. Since 1986, Dr. Lichteneg...
Activity theory as a challenge to systems design
Bødker, Susanne
1991-01-01
This paper suggests an improvement of the theoretical foundation of information systems research of the 1990s. This foundation is found in human activity theory. The paper deals with how human activity theory can help systems design change, theoretically and practically. Applying activity theory...
The Systemic Theory of Living Systems and Relevance to CAM
José A. Olalde Rangel
2005-01-01
Full Text Available The Systemic Theory of Living Systems is being published in several parts in eCAM. The theory is axiomatic. It originates from the phenomenological idea that physiological health is based on three factors: integrity of its structure or organization, O, functional organic energy reserve, E, and level of active biological intelligence, I. From the theory is derived a treatment strategy called Systemic Medicine (SM. This is based on identifying and prescribing phytomedicines and/or other medications that strengthen each factor. Energy-stimulating phytomedicines increase available energy and decrease total entropy of an open biological system by providing negative entropy. The same occurs with phytomedicines that act as biological intelligence modulators. They should be used as the first line of treatment in all ailments, since all pathologies, by definition, imply a higher than normal organic entropy. SM postulates that the state of health, H, of an individual, is effectively equal to the product of the strength of each factor H = O × E × I. SM observes that when all three factors are brought back to ideal levels, patients' conditions begin the recovery to normal health.
Philosophical Smoke Signals: Theory and Practice in Information Systems Design
King, David
2008-01-01
Although the gulf between the theory and practice in Information Systems is much lamented, few researchers have offered a way forward except through a number of (failed) attempts to develop a single systematic theory for Information Systems. In this paper, we encourage researchers to re-examine the practical consequences of their theoretical arguments. By examining these arguments we may be able to form a number of more rigorous theories of Information Systems, allowing us to draw theory and practice together without undertaking yet another attempt at the holy grail of a single unified systematic theory of Information Systems.
TOWARD A THEORY OF SUSTAINABLE SYSTEMS
While there is tremendous interest in the topic of sustainability, a fundamental theory of sustainability does not exist. We present our efforts at constructing such a theory starting with Information Theory and ecological models. We discuss the state of complex sustainable syste...
Nonlinear gravity-wave interactions in stratified turbulence
Remmel, Mark; Sukhatme, Jai; Smith, Leslie M.
2014-04-01
To investigate the dynamics of gravity waves in stratified Boussinesq flows, a model is derived that consists of all three-gravity-wave-mode interactions (the GGG model), excluding interactions involving the vortical mode. The GGG model is a natural extension of weak turbulence theory that accounts for exact three-gravity-wave resonances. The model is examined numerically by means of random, large-scale, high-frequency forcing. An immediate observation is a robust growth of the so-called vertically sheared horizontal flow (VSHF). In addition, there is a forward transfer of energy and equilibration of the nonzero-frequency (sometimes called "fast") gravity-wave modes. These results show that gravity-wave-mode interactions by themselves are capable of systematic interscale energy transfer in a stratified fluid. Comparing numerical simulations of the GGG model and the full Boussinesq system, for the range of Froude numbers ( Fr) considered (0.05 ≤ Fr ≤ 1), in both systems the VSHF is hardest to resolve. When adequately resolved, VSHF growth is more vigorous in the GGG model. Furthermore, a VSHF is observed to form in milder stratification scenarios in the GGG model than the full Boussinesq system. Finally, fully three-dimensional nonzero-frequency gravity-wave modes equilibrate in both systems and their scaling with vertical wavenumber follows similar power-laws. The slopes of the power-laws obtained depend on Fr and approach -2 (from above) at Fr = 0.05, which is the strongest stratification that can be properly resolved with our computational resources.
The Systemic Theory of Living Systems and Relevance to CAM: The Theory (Part II)
2005-01-01
This theory stems from observing the universe's ‘omniscient’ nature, manifested in flows of energy and information of its life plethora. A notorious example is the living cell's intelligent nature, which guides its basic goal: to maximize survival. This last motivated me to address the living system's intelligence, which constitutes a vital and controversial topic, its relationship with ‘incurable’ disease in general, including cancer, and to propose golden rules for therapeutics, as well as a definition of ideal medicine. The scientific confirmation of these findings is embedded in discoveries in cybernetics, biological theory of information and modern thermodynamic concepts, concerning energy and information exchange, within a living system. This approach's practical application, denominated Systemic Medicine, has been substantiated by treatment and results obtained in >300 000 patients suffering from chronic degenerative diseases. PMID:15937552
General Open Systems Theory and the Substrata-Factor Theory of Reading.
Kling, Martin
This study was designed to extend the generality of the Substrata-Factor Theory by two methods of investigation: (1) theoretically, to est"blish the validity of the hypothesis that an isomorphic relationship exists between the Substrata-Factor Theory and the General Open Systems Theory, and (2) experimentally, to disc"ver through a…
Theory of Neural Information Processing Systems
Galla, Tobias [Abdus Salam International Centre for Theoretical Physics and INFM/CNR SISSA-Unit, Strada Costiera 11, I-34014 Trieste (Italy)
2006-04-07
It is difficult not to be amazed by the ability of the human brain to process, to structure and to memorize information. Even by the toughest standards the behaviour of this network of about 10{sup 11} neurons qualifies as complex, and both the scientific community and the public take great interest in the growing field of neuroscience. The scientific endeavour to learn more about the function of the brain as an information processing system is here a truly interdisciplinary one, with important contributions from biology, computer science, physics, engineering and mathematics as the authors quite rightly point out in the introduction of their book. The role of the theoretical disciplines here is to provide mathematical models of information processing systems and the tools to study them. These models and tools are at the centre of the material covered in the book by Coolen, Kuehn and Sollich. The book is divided into five parts, providing basic introductory material on neural network models as well as the details of advanced techniques to study them. A mathematical appendix complements the main text. The range of topics is extremely broad, still the presentation is concise and the book well arranged. To stress the breadth of the book let me just mention a few keywords here: the material ranges from the basics of perceptrons and recurrent network architectures to more advanced aspects such as Bayesian learning and support vector machines; Shannon's theory of information and the definition of entropy are discussed, and a chapter on Amari's information geometry is not missing either. Finally the statistical mechanics chapters cover Gardner theory and the replica analysis of the Hopfield model, not without being preceded by a brief introduction of the basic concepts of equilibrium statistical physics. The book also contains a part on effective theories of the macroscopic dynamics of neural networks. Many dynamical aspects of neural networks are usually hard
Solar-System Tests of Gravitational Theories
Shapiro, Irwin
1997-01-01
We are engaged in testing gravitational theory by means of observations of objects in the solar system. These tests include an examination of the Principle Of Equivalence (POE), the Shapiro delay, the advances of planetary perihelia, the possibility of a secular variation G in the "gravitational constant" G, and the rate of the de Sitter (geodetic) precession of the Earth-Moon system. These results are consistent with our preliminary results focusing on the contribution of Lunar Laser Ranging (LLR), which were presented at the seventh Marcel Grossmann meeting on general relativity. The largest improvement over previous results comes in the uncertainty for (eta): a factor of five better than our previous value. This improvement reflects the increasing strength of the LLR data. A similar analysis presented at the same meeting by a group at the Jet Propulsion Laboratory gave a similar result for (eta). Our value for (beta) represents our first such result determined simultaneously with the solar quadrupole moment from the dynamical data set. These results are being prepared for publication. We have shown how positions determined from different planetary ephemerides can be compared and how the combination of VLBI and pulse timing information can yield a direct tie between planetary and radio frames. We have continued to include new data in our analysis as they became available. Finally, we have made improvement in our analysis software (PEP) and ported it to a network of modern workstations from its former home on a "mainframe" computer.
On turbulence in a stratified environment
Sarkar, Sutanu
2015-11-01
John Lumley, motivated by atmospheric observations, made seminal contributions to the statistical theory (Lumley and Panofsky 1964, Lumley 1964) and second-order modeling (Zeman and Lumley 1976) of turbulence in the environment. Turbulent processes in the ocean share many features with the atmosphere, e.g., shear, stratification, rotation and rough topography. Results from direct and large eddy simulations of two model problems will be used to illustrate some of the features of turbulence in a stratified environment. The first problem concerns a shear layer in nonuniform stratification, a situation typical of both the atmosphere and the ocean. The second problem, considered to be responsible for much of the turbulent mixing that occurs in the ocean interior, concerns topographically generated internal gravity waves. Connections will be made to data taken during observational campaigns in the ocean.
The Systemic Theory of Living Systems and Relevance to CAM: the Theory (Part III)
2005-01-01
Western medical science lacks a solid philosophical and theoretical approach to disease cognition and therapeutics. My first two articles provided a framework for a humane medicine based on Modern Biophysics. Its precepts encompass modern therapeutics and CAM. Modern Biophysics and its concepts are presently missing in medicine, whether orthodox or CAM, albeit they probably provide the long sought explanation that bridges the abyss between East and West. Key points that differentiate Systemic from other systems' approaches are ‘Intelligence’, ‘Energy’ and the objective ‘to survive’. The General System Theory (GST) took a forward step by proposing a departure from the mechanistic biological concept—of analyzing parts and processes in isolation—and brought us towards an organismic model. GST examines the system's components and results of their interaction. However, GST still does not go far enough. GST assumes ‘Self-Organization’ as a spontaneous phenomenon, ignoring a causative entity or central controller to all systems: Intelligence. It also neglects ‘Survive’ as the directional motivation common to any living system, and scarcely assigns ‘Energy’ its true inherent value. These three parameters, Intelligence, Energy and Survive, are vital variables to be considered, in our human quest, if we are to achieve a unified theory of life. PMID:16136205
Control System Design Using Finite Laplace Transform Theory
Das, Subhendu
2011-01-01
The Laplace transform theory violates a very fundamental requirement of all engineering systems. We show that this theory assumes that all signals must exist over infinite time interval. Since in engineering this infinite time assumption is not meaningful and feasible, this paper presents a design for linear control systems using the well known theory of Finite Laplace transform (FLT). The major contributions of this paper can be listed as: (a) A design principle for linear control systems us...
The Female Voice: Applications to Bowen's Family Systems Theory.
Knudson-Martin, Carmen
1994-01-01
Responds to calls from feminist scholars to address potential biases against women in theories of family therapy. Summarizes findings from studies of female development and integrates findings into expanded model of Bowen's family systems theory. Includes case example comparing expanded model with traditional application of Bowen's theory.…
MANAGERIAL DECISION IN INNOVATIVE EDUCATION SYSTEMS STATISTICAL SURVEY BASED ON SAMPLE THEORY
Gheorghe SĂVOIU
2012-12-01
Full Text Available Before formulating the statistical hypotheses and the econometrictesting itself, a breakdown of some of the technical issues is required, which are related to managerial decision in innovative educational systems, the educational managerial phenomenon tested through statistical and mathematical methods, respectively the significant difference in perceiving the current qualities, knowledge, experience, behaviour and desirable health, obtained through a questionnaire applied to a stratified population at the end,in the educational environment, either with educational activities, or with simultaneously managerial and educational activities. The details having to do with research focused on the survey theory, turning into a working tool the questionnaires and statistical data that are processed from those questionnaires, are summarized below.
Electromagnetic fields in stratified media
Li, Kai
2009-01-01
Dealing with an important branch of electromagnetic theory with many useful applications in subsurface communication, radar, and geophysical prospecting and diagnostics, this book introduces electromagnetic theory and wave propagation in complex media.
Lederman, Linda Costigan; Rogers, Don
The two papers in this document focus on general systems theory. In her paper, Linda Lederman discusses the emergence and evolution of general systems theory, defines its central concepts, and draws some conclusions regarding the nature of the theory and its value as an epistemology. Don Rogers, in his paper, relates some of the important features…
Some open problems in random matrix theory and the theory of integrable systems
Deift, Percy
2007-01-01
We describe a list of open problems in random matrix theory and integrable systems which was presented at the conference ``Integrable Systems, Random Matrices, and Applications'' at the Courant Institute in May 2006.
Some open problems in random matrix theory and the theory of integrable systems
Deift, Percy
2007-01-01
We describe a list of open problems in random matrix theory and integrable systems which was presented at the conference ``Integrable Systems, Random Matrices, and Applications'' at the Courant Institute in May 2006.
LeGare, M
1987-04-01
The general designations of neural systems and their levels of organization as presently applied in the neurosciences are described as being at variance with rigorous systems thinking. It is proposed that the rule-driven use of systems terminology and hierarchies would facilitate investigations of neural functioning in the natural case. General systems theory with its major propositions for hierarchical organization, open systems, and equifinality, is presented as providing the guidelines for developing systems-type theories for neuroscience investigations. General systems theory as metatheory is also used to evaluate hierarchies and systems designations in the neurosciences as these concepts are now applied in theories, models, and research. The metatheory is comprised of three sets of rules: the criteria for hierarchies; the properties of the open biological system; the criteria for the final conditions of open biological systems. The notion of the discovery of neural systems is contrasted with the apparent design of systems as frequently practiced by neuroscientists. The metatheory is summarized as directions for developing theories and as questions directed toward any neuroscience theory proposing levels of organization and systems.
Behavior, Organization, Substance: Three Gestalts of General Systems Theory
De Florio, Vincenzo
2014-01-01
The term gestalt, when used in the context of general systems theory, assumes the value of "systemic touchstone", namely a figure of reference used to categorize the properties or qualities of a set of systems. Typical gestalts used in biology are those based on anatomical or physiological characteristics, which correspond respectively to architectural and organizational design choices in natural and artificial systems. In this paper we discuss three gestalts of general systems theory: behavi...
Guiasu, Silviu
1979-01-01
Coalition and Connection in Games: Problems of Modern Game Theory using Methods Belonging to Systems Theory and Information Theory focuses on coalition formation and on connections occurring in games, noting the use of mathematical models in the evaluation of processes involved in games. The book first takes a look at the process of strategy in playing games in which the conditional choices of players are noted. The sequence of decisions during the playing of games and observance of the rules are emphasized. The text also ponders on the mathematical tool of game theory in which the differences
String theory as a diffusing system
Calcagni, Gianluca
2009-01-01
Recent results on the effective non-local dynamics of the tachyon mode of open string field theory (OSFT) show that approximate solutions can be constructed which obey the diffusion equation. We argue that this structure is inherited from the full theory, where it admits a background-independent formulation. In fact, all known exact OSFT solutions are superpositions of diffusing surface states. In particular, the diffusion equation is a spacetime manifestation of OSFT gauge symmetries.
Mathematical Systems Theory : from Behaviors to Nonlinear Control
Julius, A; Pasumarthy, Ramkrishna; Rapisarda, Paolo; Scherpen, Jacquelien
2015-01-01
This treatment of modern topics related to mathematical systems theory forms the proceedings of a workshop, Mathematical Systems Theory: From Behaviors to Nonlinear Control, held at the University of Groningen in July 2015. The workshop celebrated the work of Professors Arjan van der Schaft and Harry Trentelman, honouring their 60th Birthdays. The first volume of this two-volume work covers a variety of topics related to nonlinear and hybrid control systems. After giving a detailed account of the state of the art in the related topic, each chapter presents new results and discusses new directions. As such, this volume provides a broad picture of the theory of nonlinear and hybrid control systems for scientists and engineers with an interest in the interdisciplinary field of systems and control theory. The reader will benefit from the expert participants’ ideas on exciting new approaches to control and system theory and their predictions of future directions for the subject that were discussed at the worksho...
Torsion theories of pseudo-regular S-systems
无
2002-01-01
The concept of pseudo-regular S-system is introduced. A torsion theory τu = ( Us, Us) with its torsion class Us consisting of pseudo-regular S-systems is constructed. Its corresponding quasi-filter is completely described. A number of results on the relations between τu and two special torsion theories, the stable and Larnbek torsion theories, are obtained.
Certified Satisfiability Module Theories (SMT) Solving for System Verification
2017-01-01
CERTIFIED SATISFIABILITY MODULO THEORIES (SMT) SOLVING FOR SYSTEM VERIFICATION NEW YORK UNIVERSITY JANUARY 2017 FINAL TECHNICAL REPORT APPROVED...COVERED (From - To) AUG 2013 – JUL 2016 4. TITLE AND SUBTITLE CERTIFIED SATISFIABILITY MODULO THEORIES (SMT) SOLVING FOR SYSTEM VERIFICATION 5a...describes the results of efforts to do exactly this. CVC4, a modern, open - source solver for Satisfiability Modulo Theories (SMT), has been instrumented
What can systems and control theory do for agricultural science?
Straten, van G.
2008-01-01
Abstract: While many professionals with a background in agricultural and bio-resource sciences work with models, only few have been exposed to systems and control theory. The purpose of this paper is to elucidate a selection of methods from systems theory that can be beneficial to quantitative agric
General Systems Theory Approaches to Organizations: Some Problems in Application
Peery, Newman S., Jr.
1975-01-01
Considers the limitations of General Systems Theory (GST) as a major paradigm within administrative theory and concludes that most systems formulations overemphasize growth and show little appreciation for intraorganizational conflict, diversity of values, and political action within organizations. Suggests that these limitations are mainly due to…
Lie transform Hamiltonian perturbation theory for limit cycle systems
Shah, Tirth; Chakraborty, Sagar
2016-01-01
Usage of a Hamiltonian perturbation theory for nonconservative system is counterintuitive and in general, a technical impossibility by definition. However, the dual (time independent) Hamiltonian formalism for nonconservative systems have opened the door for using various Hamiltonian (and hence, Lagrangian) perturbation theories for investigating the dynamics of such systems. Following the recent extension of the canonical perturbation theory that brings Li\\'enard systems possessing limit cycles under its scope, here we show that the Lie transform Hamiltonian perturbation theory can also be generalized to find perturbative solutions for similar systems. The Lie transform perturbation theories are comparatively easier while seeking higher order corrections in the perturbative series for the solutions and they are also numerically implementable using any symbolic algebra package. For the sake of concreteness, we have illustrated the methodology using the important example of the van der Pol oscillator. While th...
Dynamical Systems and Control Theory Inspired by Molecular Biology
2014-10-02
in both bacterial and eukaryotic signaling pathways. A common theme in the systems biology literature is that certain systems whose output variables...AFRL-OSR-VA-TR-2014-0282 DYNAMICAL SYSTEMS AND CONTROL THEORY INSPIRED BY MOLECULAR BIOLOGY Eduardo Sontag RUTGERS THE STATE UNIVERSITY OF NEW JERSEY...Standard Form 298 (Re . 8-98) v Prescribed by ANSI Std. Z39.18 DYNAMICAL SYSTEMS AND CONTROL THEORY INSPIRED BY MOLECULAR BIOLOGY AFOSR FA9550-11-1-0247
Continuous and distributed systems theory and applications
Sadovnichiy, Victor
2014-01-01
In this volume, the authors close the gap between abstract mathematical approaches, such as abstract algebra, number theory, nonlinear functional analysis, partial differential equations, methods of nonlinear and multi-valued analysis, on the one hand, and practical applications in nonlinear mechanics, decision making theory and control theory on the other. Readers will also benefit from the presentation of modern mathematical modeling methods for the numerical solution of complicated engineering problems in hydromechanics, geophysics and mechanics of continua. This compilation will be of interest to mathematicians and engineers working at the interface of these field. It presents selected works of the open seminar series of Lomonosov Moscow State University and the National Technical University of Ukraine “Kyiv Polytechnic Institute”. The authors come from Germany, Italy, Spain, Russia, Ukraine, and the USA.
Personal Construct Theory and Systemic Therapies: Parallel or Convergent Trends?
Feixas, Guillem
1990-01-01
Explores similarities between Kelly's Personal Construct Theory (PCT) and systemic therapies. Asserts that (1) PCT and systemic therapies share common epistemological stance, constructivism; (2) personal construct systems possess properties of open systems; and (3) PCT and systemic therapies hold similar positions on relevant theoretical and…
Recent applications of Kirkwood-Buff theory to biological systems.
Pierce, Veronica; Kang, Myungshim; Aburi, Mahalaxmi; Weerasinghe, Samantha; Smith, Paul E
2008-01-01
The effect of cosolvents on biomolecular equilibria has traditionally been rationalized using simple binding models. More recently, a renewed interest in the use of Kirkwood-Buff (KB) theory to analyze solution mixtures has provided new information on the effects of osmolytes and denaturants and their interactions with biomolecules. Here we review the status of KB theory as applied to biological systems. In particular, the existing models of denaturation are analyzed in terms of KB theory, and the use of KB theory to interpret computer simulation data for these systems is discussed.
Algebraic structure and Poisson's theory of mechanico-electrical systems
Liu Hong-Ji; Tang Yi-Fa; Fu Jing-Li
2006-01-01
The algebraic structure and Poisson's integral theory of mechanico-electrical systems are studied.The Hamilton canonical equations and generalized Hamilton canonical equations and their the contravariant algebraic forms for mechanico-electrical systems are obtained.The Lie algebraic structure and the Poisson's integral theory of Lagrange mechanico-electrical systems are derived.The Lie algebraic structure admitted and Poisson's integral theory of the Lagrange-Maxwell mechanico-electrical systems are presented.Two examples are presented to illustrate these results.
N=2 supersymmetric gauge theories and quantum integrable systems
Luo, Yuan; Tan, Meng-Chwan [Department of Physics, National University of Singapore 2 Science Drive 3, 117551 (Singapore); Yagi, Junya [Department of Physics, National University of Singapore 2 Science Drive 3, 117551 (Singapore); International School for Advanced Studies (SISSA) Via Bonomea, 265, 34136 Trieste (Italy); INFN, Sezione di Trieste Via Valerio, 2, 34149 Trieste (Italy)
2014-03-20
We study N=2 supersymmetric gauge theories on the product of a two-sphere and a cylinder. We show that the low-energy dynamics of a BPS sector of such a theory is described by a quantum integrable system, with the Planck constant set by the inverse of the radius of the sphere. If the sphere is replaced with a hemisphere, then our system reduces to an integrable system of the type studied by Nekrasov and Shatashvili. In this case we establish a correspondence between the effective prepotential of the gauge theory and the Yang-Yang function of the integrable system.
On activity theory in cognitive systems
Abolfazlian, Ali Reza Kian
Theory' (Virksomhedsteori). Virksomhedsteori er den dominante teori i den sovjetiske tradition af social psykologi. Virksomhedsteori startede med Vygotskys arbejde og fortsatte sin vækst under vejledningen af forskere som Leontiev og Luria. Med sit erkendelsesteoretiske program baseret på interaktion med...
The Einstein-Vlasov System/Kinetic Theory
Håkan Andréasson
2011-05-01
Full Text Available The main purpose of this article is to provide a guide to theorems on global properties of solutions to the Einstein-Vlasov system. This system couples Einstein’s equations to a kinetic matter model. Kinetic theory has been an important field of research during several decades in which the main focus has been on non-relativistic and special relativistic physics, i.e., to model the dynamics of neutral gases, plasmas, and Newtonian self-gravitating systems. In 1990, Rendall and Rein initiated a mathematical study of the Einstein-Vlasov system. Since then many theorems on global properties of solutions to this system have been established. This paper gives introductions to kinetic theory in non-curved spacetimes and then the Einstein–Vlasov system is introduced. We believe that a good understanding of kinetic theory in non-curved spacetimes is fundamental to a good comprehension of kinetic theory in general relativity.
Stratified wake of an accelerating hydrofoil
Ben-Gida, Hadar; Gurka, Roi
2015-01-01
Wakes of towed and self-propelled bodies in stratified fluids are significantly different from non-stratified wakes. Long time effects of stratification on the development of the wakes of bluff bodies moving at constant speed are well known. In this experimental study we demonstrate how buoyancy affects the initial growth of vortices developing in the wake of a hydrofoil accelerating from rest. Particle image velocimetry measurements were applied to characterize the wake evolution behind a NACA 0015 hydrofoil accelerating in water and for low Reynolds number and relatively strong and stably stratified fluid (Re=5,000, Fr~O(1)). The analysis of velocity and vorticity fields, following vortex identification and an estimate of the circulation, reveal that the vortices in the stratified fluid case are stretched along the streamwise direction in the near wake. The momentum thickness profiles show lower momentum thickness values for the stratified late wake compared to the non-stratified wake, implying that the dra...
Carmo, Carolina; Dumont, Olivier; Nielsen, Mads Pagh
2015-01-01
The use of stratified hot water tanks in solar energy systems - including ORC systems - as well as heat pump systems is paramount for a better performance of these systems. However, the availability of effective and reliable models to predict the annual performance of stratified hot water tanks c...
An Activity Systems Theory Approach to Agent Technology
Zhang, Peng; Bai, Guohua
2005-01-01
In the last decade, Activity Theory has been discussed a lot in Human-Computer Interaction (HCI) and Computer Supported Cooperative Work (CSCW). Activity Theory was used both theoretically as an analytical method and practically as a development framework for Information Systems. Meanwhile, there is a new trench from Artificial Intelligence. Artificial Intelligence researchers find that the fruit from Activity Theory study may contribute, especially to Agent Technology, with socio-psychologic...
Recent Applications of Kirkwood-Buff Theory to Biological Systems
Pierce, Veronica; Kang, Myungshim; Aburi, Mahalaxmi; Weerasinghe, Samantha; Smith, Paul E.
2007-01-01
The effect of cosolvents on biomolecular equilibria has traditionally been rationalized using simple binding models. More recently, a renewed interest in the use of Kirkwood-Buff (KB) theory to analyze solution mixtures has provided new information on the effects of osmolytes and denaturants and their interactions with biomolcules. Here we review the status of KB theory as applied to biological systems. In particular, the existing models of denaturation are analyzed in terms of KB theory, and...
ELEMENTS OF APPROXIMATION THEORY FOR SIGNALS AND SYSTEMS.
The report contains an exposition of the essentials of the theory of linear least square approximation for scientists. Its format is based on the...has some knowledge of Hilbert space theory. The unifying concept which prevails throughout the report allows the treatment of the problems of least ... square approximation in a variety of fields. Applications to problems of linear systems, networks, and communication theory are included. (Author)
How stratified is mantle convection?
Puster, Peter; Jordan, Thomas H.
1997-04-01
We quantify the flow stratification in the Earth's mid-mantle (600-1500 km) in terms of a stratification index for the vertical mass flux, Sƒ (z) = 1 - ƒ(z) / ƒref (z), in which the reference value ƒref(z) approximates the local flux at depth z expected for unstratified convection (Sƒ=0). Although this flux stratification index cannot be directly constrained by observations, we show from a series of two-dimensional convection simulations that its value can be related to a thermal stratification index ST(Z) defined in terms of the radial correlation length of the temperature-perturbation field δT(z, Ω). ST is a good proxy for Sƒ at low stratifications (SƒUniformitarian Principle. The bound obtained here from global tomography is consistent with local seismological evidence for slab flux into the lower mantle; however, the total material flux has to be significantly greater (by a factor of 2-3) than that due to slabs alone. A stratification index, Sƒ≲0.2, is sufficient to exclude many stratified convection models still under active consideration, including most forms of chemical layering between the upper and lower mantle, as well as the more extreme versions of avalanching convection governed by a strong endothermic phase change.
Circular Economy Development Mode Based on System Theory
Xiao Huamao; Wang Fengqi
2007-01-01
The paper tries to explore circular economy from the viewpoint of the system theory.Circular economy is a kind of complicated economic acdvity,and it is a wholly new ecotype economy pmposed by Western countries after they had summed up many experiences and lessons from traditional economy.It is an entirety and has many layers.It keeps an open and dynamic balance.Because the system theory is the theoretical foundation of circular economy,we should systemically analyze and study circular economy from the macroscopic view,correctly grasp its operational laws,improve its service functions,and realize human beings's ustainable development.The paper introduces the content and general characteristics of the system theory and the idea of circular economy.Then it analyzes circular economy based on the systemtheory.The paper concludes that the intonation of circular economy and the system theory can promote the functions of circular economy.
Contributions of Dynamic Systems Theory to Cognitive Development
Spencer, John P.; Austin, Andrew; Schutte, Anne R.
2012-01-01
We examine the contributions of dynamic systems theory to the field of cognitive development, focusing on modeling using dynamic neural fields. After introducing central concepts of dynamic field theory (DFT), we probe empirical predictions and findings around two examples--the DFT of infant perseverative reaching that explains Piaget's A-not-B…
Contributions of Dynamic Systems Theory to Cognitive Development
Spencer, John P.; Austin, Andrew; Schutte, Anne R.
2012-01-01
We examine the contributions of dynamic systems theory to the field of cognitive development, focusing on modeling using dynamic neural fields. After introducing central concepts of dynamic field theory (DFT), we probe empirical predictions and findings around two examples--the DFT of infant perseverative reaching that explains Piaget's A-not-B…
General systems theory and scientific interpretation of social reality
Kaluzhsky, Mikhail
2001-01-01
An article about the use of the methodology of general systems theory and the theory of self-organization as a methodological basis of scientific interpretation of social reality. The author analyzes the role of ideology and propaganda in the different concepts of interpretation of social reality (social Darwinism, Marxism, etc.). The main conclusion of the paper is the need deideologization scientific knowledge.
Multicomponent density-functional theory for time-dependent systems
Butriy, O.; Ebadi, H.; de Boeij, P. L.; van Leeuwen, R.; Gross, E. K. U.
2007-01-01
We derive the basic formalism of density functional theory for time-dependent electron-nuclear systems. The basic variables of this theory are the electron density in body-fixed frame coordinates and the diagonal of the nuclear N-body density matrix. The body-fixed frame transformation is carried ou
Bayesian Stratified Sampling to Assess Corpus Utility
Hochberg, J; Thomas, T; Hall, S; Hochberg, Judith; Scovel, Clint; Thomas, Timothy; Hall, Sam
1998-01-01
This paper describes a method for asking statistical questions about a large text corpus. We exemplify the method by addressing the question, "What percentage of Federal Register documents are real documents, of possible interest to a text researcher or analyst?" We estimate an answer to this question by evaluating 200 documents selected from a corpus of 45,820 Federal Register documents. Stratified sampling is used to reduce the sampling uncertainty of the estimate from over 3100 documents to fewer than 1000. The stratification is based on observed characteristics of real documents, while the sampling procedure incorporates a Bayesian version of Neyman allocation. A possible application of the method is to establish baseline statistics used to estimate recall rates for information retrieval systems.
Integrable Hamiltonian systems and spectral theory
Moser, J
1981-01-01
Classical integrable Hamiltonian systems and isospectral deformations ; geodesics on an ellipsoid and the mechanical system of C. Neumann ; the Schrödinger equation for almost periodic potentials ; finite band potentials ; limit cases, Bargmann potentials.
2010-12-22
median survival after systemic 5-Fluorouracil/Leucovorin ( 5FU /L) based chemotherapy for PC of colorectal cancer can, under the best of circumstances...type of systemic chemotherapy regimen; no chemotherapy (best supportive care), 5-Fluorouracil/Leucovorin ( 5FU /L), or modern chemotherapy...Eighty-three patients (50%) had no chemotherapy treatment and received best supportive care only. Forty-two patients (25%) received 5FU /L chemotherapy
StudiesonSecondLanguageAcquisitionfromthePerspectiveof DynamicSystemTheory
赵哲
2014-01-01
As is known there are large numbers of studies on Second Language Acquisition. However, Dynamic System Theory is the new trend in Applied Linguistics. It is necessary to probe into this field and see if it has relationship with SLA.
Clinical Perspective Linking theory and technique in a systems ...
Clinical Perspective Linking theory and technique in a systems approach to learning ... children with learning problems (due to factors other than cognitive deficits), ... children have been raised — the post apartheid socio-cultural environment, ...
JIT supply chain; an investigation through general system theory
O P Mishra
2013-03-01
Full Text Available This paper explains theoretical approach of the four theories of General system Theory (GST developed by Yourdon (1989 [Yourdon, E. (1989. Modern Structured Analysis. Yourdon Press, Prentice-Hall International, Englewood Cliffs, New Jersey. Senge] while applying it in information technology and subsequently used by caddy (2007 [Caddy I.N., & Helou, M.M. (2007. Supply chains and their management: Application of general systems theory. Journal of Retailing and Consumer Services, 14, 319–327.] in field of supply chain and management. JIT philosophy in core activities of supply chain i.e. procurement, production processes, and logistics are discussed through general system theory. The growing structure of the supply chain poses the implication restrictions and requires a heavy support system, many times a compromise is done while implementing JIT. The study would be useful to understand the general trends generated naturally regarding the adoption of the JIT philosophy in the supply chain.
A historical approach to the general theory of systems
Esther María Pino Guzmán
2015-01-01
The paper is intended to examine the epistemological development of the theory or systems, focus the change of its scientific paradigm and points out its main implications for the development of research methodology and design. The theoretical methods being used makes possible to go deeper into the analysis of regularities and essential qualities in the construction and development of the scientific theory. The system approach is one of the most frequently used method and the one of further r...
Stochastic chemical kinetics theory and (mostly) systems biological applications
Érdi, Péter; Lente, Gabor
2014-01-01
This volume reviews the theory and simulation methods of stochastic kinetics by integrating historical and recent perspectives, presents applications, mostly in the context of systems biology and also in combustion theory. In recent years, due to the development in experimental techniques, such as optical imaging, single cell analysis, and fluorescence spectroscopy, biochemical kinetic data inside single living cells have increasingly been available. The emergence of systems biology brought renaissance in the application of stochastic kinetic methods.
El Serafy, G.Y.H.; Mynett, A.E.
2008-01-01
Numerical models of a water system are always based on assumptions and simplifications that may result in errors in the model's predictions. Such errors can be reduced through the use of data assimilation and thus can significantly improve the success rate of the predictions and operational forecast
Mythical systems: mathematic and logical theory
Nescolarde-Selva, J.; Usó-Doménech, J. L.; Lloret-Climent, M.
2015-01-01
The process of elaboration of the symbolic universe leads to exciting insights regarding the search for human emotional security. The symbols end up as explanatory axes of universal reality and on them are constructed myths that form a superstructure for belief systems. Human society is a multi-level system with a material structure (society), an ideological superstructure (belief systems, values, etc.) and a super superstructure with two parts: mythical (origin and justification) and utopic (final goal). All mythical belief systems have a numinous-religious nature.
Emergent “quantum” theory in complex adaptive systems
Minic, Djordje; Pajevic, Sinisa
2016-03-01
Motivated by the question of stability, in this paper we argue that an effective quantum-like theory can emerge in complex adaptive systems. In the concrete example of stochastic Lotka-Volterra dynamics, the relevant effective “Planck constant” associated with such emergent “quantum” theory has the dimensions of the square of the unit of time. Such an emergent quantum-like theory has inherently nonclassical stability as well as coherent properties that are not, in principle, endangered by thermal fluctuations and therefore might be of crucial importance in complex adaptive systems.
Core science: Stratified by a sunken impactor
Nakajima, Miki
2016-10-01
There is potential evidence for a stratified layer at the top of the Earth's core, but its origin is not well understood. Laboratory experiments suggest that the stratified layer could be a sunken remnant of the giant impact that formed the Moon.
Theory and practice in machining systems
Ito, Yoshimi
2017-01-01
This book describes machining technology from a wider perspective by considering it within the machining space. Machining technology is one of the metal removal activities that occur at the machining point within the machining space. The machining space consists of structural configuration entities, e.g., the main spindle, the turret head and attachments such the chuck and mandrel, and also the form-generating movement of the machine tool itself. The book describes fundamental topics, including the form-generating movement of the machine tool and the important roles of the attachments, before moving on to consider the supply of raw materials into the machining space, and the discharge of swarf from it, and then machining technology itself. Building on the latest research findings “Theory and Practice in Machining System” discusses current challenges in machining. Thus, with the inclusion of introductory and advanced topics, the book can be used as a guide and survey of machining technology for students an...
Jensen, Tina Blegind; Kjærgaard, Annemette; Svejvig, Per
2009-01-01
Institutional theory has proven to be a central analytical perspective for investigating the role of social and historical structures of information systems (IS) implementation. However, it does not explicitly account for how organisational actors make sense of and enact technologies in their local...... context. We address this limitation by exploring the potential of using institutional theory with sensemaking theory to study IS implementation in organisations. We argue that each theoretical perspective has its own explanatory power and that a combination of the two facilitates a much richer...... interpretation of IS implementation by linking macro- and micro-levels of analysis. To illustrate this, we report from an empirical study of the implementation of an Electronic Patient Record (EPR) system in a clinical setting. Using key constructs from the two theories, our findings address the phenomenon...
Jensen, Tina Blegind; Kjærgaard, Annemette; Svejvig, Per
2009-01-01
Institutional theory has proven to be a central analytical perspective for investigating the role of social and historical structures of information systems (IS) implementation. However, it does not explicitly account for how organisational actors make sense of and enact technologies in their local...... context. We address this limitation by exploring the potential of using institutional theory with sensemaking theory to study IS implementation in organisations. We argue that each theoretical perspective has its own explanatory power and that a combination of the two facilitates a much richer...... interpretation of IS implementation by linking macro- and micro-levels of analysis. To illustrate this, we report from an empirical study of the implementation of an Electronic Patient Record (EPR) system in a clinical setting. Using key constructs from the two theories, our findings address the phenomenon...
Artificial Intelligence Theory and Reconfigurable Control Systems.
1984-06-30
IEEE Transactions on Automatic Control , Vol...AC-iS, No. 1, Feb 1970. 5. Sklansky, J., "Learning Systems for Automatic Control", IEEE = Transactions on Automatic Control , Vol...34A Gerfcale itellihoode Raio ,-. ~Aproc tohemesecio and Ca Suis nwEtimat eeion" (: Jump in-Linea & -,"Ŗ. Systems", IEEE Transactions on Automatic Control ,
The Neuman Systems Model Institute: testing middle-range theories.
Gigliotti, Eileen
2003-07-01
The credibility of the Neuman systems model can only be established through the generation and testing of Neuman systems model-derived middle-range theories. However, due to the number and complexity of Neuman systems model concepts/concept interrelations and the diversity of middle-range theory concepts linked to these Neuman systems model concepts by researchers, no explicit middle-range theories have yet been derived from the Neuman systems model. This article describes the development of an organized program for the systematic study of the Neuman systems model. Preliminary work, already accomplished, is detailed, and a tentative plan for the completion of further preliminary work as well as beginning the actual research conduction phase is proposed.
Stratified scaffold design for engineering composite tissues.
Mosher, Christopher Z; Spalazzi, Jeffrey P; Lu, Helen H
2015-08-01
A significant challenge to orthopaedic soft tissue repair is the biological fixation of autologous or allogeneic grafts with bone, whereby the lack of functional integration between such grafts and host bone has limited the clinical success of anterior cruciate ligament (ACL) and other common soft tissue-based reconstructive grafts. The inability of current surgical reconstruction to restore the native fibrocartilaginous insertion between the ACL and the femur or tibia, which minimizes stress concentration and facilitates load transfer between the soft and hard tissues, compromises the long-term clinical functionality of these grafts. To enable integration, a stratified scaffold design that mimics the multiple tissue regions of the ACL interface (ligament-fibrocartilage-bone) represents a promising strategy for composite tissue formation. Moreover, distinct cellular organization and phase-specific matrix heterogeneity achieved through co- or tri-culture within the scaffold system can promote biomimetic multi-tissue regeneration. Here, we describe the methods for fabricating a tri-phasic scaffold intended for ligament-bone integration, as well as the tri-culture of fibroblasts, chondrocytes, and osteoblasts on the stratified scaffold for the formation of structurally contiguous and compositionally distinct regions of ligament, fibrocartilage and bone. The primary advantage of the tri-phasic scaffold is the recapitulation of the multi-tissue organization across the native interface through the layered design. Moreover, in addition to ease of fabrication, each scaffold phase is similar in polymer composition and therefore can be joined together by sintering, enabling the seamless integration of each region and avoiding delamination between scaffold layers.
Nonlinear dynamical systems for theory and research in ergonomics.
Guastello, Stephen J
2017-02-01
Nonlinear dynamical systems (NDS) theory offers new constructs, methods and explanations for phenomena that have in turn produced new paradigms of thinking within several disciplines of the behavioural sciences. This article explores the recent developments of NDS as a paradigm in ergonomics. The exposition includes its basic axioms, the primary constructs from elementary dynamics and so-called complexity theory, an overview of its methods, and growing areas of application within ergonomics. The applications considered here include: psychophysics, iconic displays, control theory, cognitive workload and fatigue, occupational accidents, resilience of systems, team coordination and synchronisation in systems. Although these applications make use of different subsets of NDS constructs, several of them share the general principles of the complex adaptive system. Practitioner Summary: Nonlinear dynamical systems theory reframes problems in ergonomics that involve complex systems as they change over time. The leading applications to date include psychophysics, control theory, cognitive workload and fatigue, biomechanics, occupational accidents, resilience of systems, team coordination and synchronisation of system components.
Stability of stratified two-phase flows in horizontal channels
Barmak, Ilya; Ullmann, Amos; Brauner, Neima; Vitoshkin, Helen
2016-01-01
Linear stability of stratified two-phase flows in horizontal channels to arbitrary wavenumber disturbances is studied. The problem is reduced to Orr-Sommerfeld equations for the stream function disturbances, defined in each sublayer and coupled via boundary conditions that account also for possible interface deformation and capillary forces. Applying the Chebyshev collocation method, the equations and interface boundary conditions are reduced to the generalized eigenvalue problems solved by standard means of numerical linear algebra for the entire spectrum of eigenvalues and the associated eigenvectors. Some additional conclusions concerning the instability nature are derived from the most unstable perturbation patterns. The results are summarized in the form of stability maps showing the operational conditions at which a stratified-smooth flow pattern is stable. It is found that for gas-liquid and liquid-liquid systems the stratified flow with smooth interface is stable only in confined zone of relatively lo...
A quest towards a mathematical theory of living systems
Bellomo, Nicola; Gibelli, Livio; Outada, Nisrine
2017-01-01
This monograph aims to lay the groundwork for the design of a unified mathematical approach to the modeling and analysis of large, complex systems composed of interacting living things. Drawing on twenty years of research in various scientific fields, it explores how mathematical kinetic theory and evolutionary game theory can be used to understand the complex interplay between mathematical sciences and the dynamics of living systems. The authors hope this will contribute to the development of new tools and strategies, if not a new mathematical theory. The first chapter discusses the main features of living systems and outlines a strategy for their modeling. The following chapters then explore some of the methods needed to potentially achieve this in practice. Chapter Two provides a brief introduction to the mathematical kinetic theory of classical particles, with special emphasis on the Boltzmann equation; the Enskog equation, mean field models, and Monte Carlo methods are also briefly covered. Chapter Three...
Control theory of digitally networked dynamic systems
Lunze, Jan
2013-01-01
The book gives an introduction to networked control systems and describes new modeling paradigms, analysis methods for event-driven, digitally networked systems, and design methods for distributed estimation and control. Networked model predictive control is developed as a means to tolerate time delays and packet loss brought about by the communication network. In event-based control the traditional periodic sampling is replaced by state-dependent triggering schemes. Novel methods for multi-agent systems ensure complete or clustered synchrony of agents with identical or with individual dynamic
Open quantum systems and random matrix theory
Mulhall, Declan
2014-10-01
A simple model for open quantum systems is analyzed with RMT. The system is coupled to the continuum in a minimal way. In this paper we see the effect of opening the system on the level statistics, in particular the level spacing, width distribution and Δ3(L) statistic are examined as a function of the strength of this coupling. The usual super-radiant state is observed, and it is seen that as it is formed, the level spacing and Δ3(L) statistic exhibit the signatures of missed levels.
Open quantum systems and random matrix theory
Mulhall, Declan [Department of Physics/Engineering, University of Scranton, Scranton, Pennsylvania 18510-4642 (United States)
2014-10-15
A simple model for open quantum systems is analyzed with RMT. The system is coupled to the continuum in a minimal way. In this paper we see the effect of opening the system on the level statistics, in particular the level spacing, width distribution and Δ{sub 3}(L) statistic are examined as a function of the strength of this coupling. The usual super-radiant state is observed, and it is seen that as it is formed, the level spacing and Δ{sub 3}(L) statistic exhibit the signatures of missed levels.
The Application of Big-Neuron Theory in Expert Systems
李涛
2001-01-01
With a new way of knowledge representation and acquirement, inference, and building an expert system based on big-neurons composed of different field expert knowledge presented, the fundamental theory and architecture of expert system based upon big-neuron theory has thus been built. It is unnecessary to organize a large number of production rules when using big-neurons to build an expert system. The facts and rules of an expert system have already been hidden in big-neurons. And also, it is unnecessary to do a great quantity of tree searching when using this method to do logic reasoning. Machine can do self-organizing and self-learning.
Theory of control systems described by differential inclusions
Han, Zhengzhi; Huang, Jun
2016-01-01
This book provides a brief introduction to the theory of finite dimensional differential inclusions, and deals in depth with control of three kinds of differential inclusion systems. The authors introduce the algebraic decomposition of convex processes, the stabilization of polytopic systems, and observations of Luré systems. They also introduce the elemental theory of finite dimensional differential inclusions, and the properties and designs of the control systems described by differential inclusions. Addressing the material with clarity and simplicity, the book includes recent research achievements and spans all concepts, concluding with a critical mathematical framework. This book is intended for researchers, teachers and postgraduate students in the area of automatic control engineering.
Theory of uniqueness of Indian Caste System
Kumar, Ashwin
2006-01-01
Classical studies on pre-modern Indian social structure have suggested apparent differences between the Indian caste system and social stratification as one can discern in other parts of the world. However, one needs to question such dogmatic assertions that such vast differences really existed. An endeavor is made in this research paper to reflect on the nature of caste hierarchy in pre-modern India. The caste system forms the significant basis of pre-modern Indian social structure. Early wr...
Cable system transients theory, modeling and simulation
Ametani, Akihiro; Nagaoka, Naoto
2015-01-01
A systematic and comprehensive introduction to electromagnetic transient in cable systems, written by the internationally renowned pioneer in this field Presents a systematic and comprehensive introduction to electromagnetic transient in cable systems Written by the internationally renowned pioneer in the field Thorough coverage of the state of the art on the topic, presented in a well-organized, logical style, from fundamentals and practical applications A companion website is available
Topological field theory of dynamical systems.
Ovchinnikov, Igor V
2012-09-01
Here, it is shown that the path-integral representation of any stochastic or deterministic continuous-time dynamical model is a cohomological or Witten-type topological field theory, i.e., a model with global topological supersymmetry (Q-symmetry). As many other supersymmetries, Q-symmetry must be perturbatively stable due to what is generically known as non-renormalization theorems. As a result, all (equilibrium) dynamical models are divided into three major categories: Markovian models with unbroken Q-symmetry, chaotic models with Q-symmetry spontaneously broken on the mean-field level by, e.g., fractal invariant sets (e.g., strange attractors), and intermittent or self-organized critical (SOC) models with Q-symmetry dynamically broken by the condensation of instanton-antiinstanton configurations (earthquakes, avalanches, etc.) SOC is a full-dimensional phase separating chaos and Markovian dynamics. In the deterministic limit, however, antiinstantons disappear and SOC collapses into the "edge of chaos." Goldstone theorem stands behind spatio-temporal self-similarity of Q-broken phases known under such names as algebraic statistics of avalanches, 1/f noise, sensitivity to initial conditions, etc. Other fundamental differences of Q-broken phases is that they can be effectively viewed as quantum dynamics and that they must also have time-reversal symmetry spontaneously broken. Q-symmetry breaking in non-equilibrium situations (quenches, Barkhausen effect, etc.) is also briefly discussed.
A systems theory approach to career decision making.
Zimmerman, Angela L; Kontosh, Larry G
2007-01-01
Many career development studies have linked career indecision, an inability to make a decision about the vocation one wishes to pursue, to interpersonal and intrapersonal processes. Systems theory can help to explain the processes behind these concepts in a way that other theories have not been able to explain. Systems Theory Framework, (STF, Patton and McMahon, 1997), incorporates both the contextual system, e.g., parents and peers, and the individual system (i.e., STF's content component). Process, the second component, identifies the presence of recursive interaction processes within the individual and the context, as well as, between the individual and the context. STF brings back the value of interdependence. Specific systemic constructs are useful in career decision-making and can add a practical dimension on to the counseling process.
A proposed organization based on systems theory
2014-01-01
The present article is about the analysis of systems for the solution of complex problems that presents in the organization in order to plan the operative design of the organization especially the system of work of high level. El presente articulo trata sobre el análisis de sistemas, orientado hacia la solución de problemas complejos que se presentan en las organizaciones, a fin de planificar el diseño operativo de la organización, en especial, el sistema de trabajo de alto desempeño.
System sizing - The theory and the practice
Teale, G. S. M.; Wolfe, P. R.
System-sizing safety margins are developed for solar power arrays providing relatively small amounts of energy at remote locations, using theoretical models and empirical data obtained by the Ministry of Petroleum and Minerals of Oman. The availability requirements of typical loads (microwave chains, single-channel VHF repeaters, and pipeline cathodic protection systems) are characterized; generator parameters (including shadowing and dust-accumulation effects) are assessed; and corrections to be applied to typical sizing programs to take these phenomena into account are presented in tables and graphs. The need for users to perform careful analyses and specify safety factors themselves is stressed.
Residue number systems theory and applications
Mohan, P V Ananda
2016-01-01
This new and expanded monograph improves upon Mohan's earlier book, Residue Number Systems (Springer, 2002) with a state of the art treatment of the subject. Replete with detailed illustrations and helpful examples, this book covers a host of cutting edge topics such as the core function, the quotient function, new Chinese Remainder theorems, and large integer operations. It also features many significant applications to practical communication systems and cryptography such as FIR filters and elliptic curve cryptography. Starting with a comprehensive introduction to the basics and leading up to current research trends that are not yet widely distributed in other publications, this book will be of interest to both researchers and students alike.
Introduction to a systemic theory of meaning
Menant, Christophe
2001-01-01
Information and meanings are present everywhere around us and within ourselves. Specific studies have been implemented in order to link information and meaning: - Semiotics/Biosemiotics - Phenomenology - Analytic Philosophy, linguistics - Psychology No general coverage is available for the notion of meaning. We propose to complement this lack by a systemic approach to meaning generation
[Development of delusion in view of Luhmann's systems theory].
Maier, T
2003-01-01
The systems theory of Niklas Luhmann declares itself as a universal theory and therefore claims applicability to any social and psychic phenomenon.In spite of its high complexity, to many it seems too vague and nonspecific. The possible usefulness of this theory should be demonstrated on the example of the development of delusion, still a mysterious and unexplained phenomenon. Within the framework of Luhmann's systems theory, delusion can be considered a communication disorder and therefore a phenomenon within the social system. Both the autopoietic systems society and psyche are based on and processed by meaning but cannot communicate directly, and they are mutually nontransparent and unpredictable. Due to this fact, the interface between the two systems is a potential source of disturbances. Luhmann defines the distinction of information, message, and understanding as the crucial element to connect the social system with the psychic one. If the psychic system fails to recognize the message of an information correctly or is unable to negotiate between understanding and misunderstanding messages, it detaches itself from the social system to which it is normally closely connected. This detachment releases the possibility of unhindered autistic fulfillment of desires and uncontrolled fear. Due to the meaning-based autopoiesis of the psychic system,these released thoughts and emotions still appear in meaningfully condensed form as delusions.
A novel classification system for evolutionary aging theories
Trindade, Lucas S.; Aigaki, Toshiro; Peixoto, Alexandre A.; Balduino, Alex; Mânica da Cruz, Ivana B.; Heddle, Jonathan G.
2013-01-01
Theories of lifespan evolution are a source of confusion amongst aging researchers. After a century of aging research the dispute over whether the aging process is active or passive persists and a comprehensive and universally accepted theoretical model remains elusive. Evolutionary aging theories primarily dispute whether the aging process is exclusively adapted to favor the kin or exclusively non-adapted to favor the individual. Interestingly, contradictory data and theories supporting both exclusively programmed and exclusively non-programmed theories continue to grow. However, this is a false dichotomy; natural selection favors traits resulting in efficient reproduction whether they benefit the individual or the kin. Thus, to understand the evolution of aging, first we must understand the environment-dependent balance between the advantages and disadvantages of extended lifespan in the process of spreading genes. As described by distinct theories, different niches and environmental conditions confer on extended lifespan a range of fitness values varying from highly beneficial to highly detrimental. Here, we considered the range of fitness values for extended lifespan and develop a fitness-based framework for categorizing existing theories. We show that all theories can be classified into four basic types: secondary (beneficial), maladaptive (neutral), assisted death (detrimental), and senemorphic aging (varying between beneficial to detrimental). We anticipate that this classification system will assist with understanding and interpreting aging/death by providing a way of considering theories as members of one of these classes rather than consideration of their individual details. PMID:23508239
A novel classification system for evolutionary aging theories.
Trindade, Lucas S; Aigaki, Toshiro; Peixoto, Alexandre A; Balduino, Alex; Mânica da Cruz, Ivana B; Heddle, Jonathan G
2013-01-01
Theories of lifespan evolution are a source of confusion amongst aging researchers. After a century of aging research the dispute over whether the aging process is active or passive persists and a comprehensive and universally accepted theoretical model remains elusive. Evolutionary aging theories primarily dispute whether the aging process is exclusively adapted to favor the kin or exclusively non-adapted to favor the individual. Interestingly, contradictory data and theories supporting both exclusively programmed and exclusively non-programmed theories continue to grow. However, this is a false dichotomy; natural selection favors traits resulting in efficient reproduction whether they benefit the individual or the kin. Thus, to understand the evolution of aging, first we must understand the environment-dependent balance between the advantages and disadvantages of extended lifespan in the process of spreading genes. As described by distinct theories, different niches and environmental conditions confer on extended lifespan a range of fitness values varying from highly beneficial to highly detrimental. Here, we considered the range of fitness values for extended lifespan and develop a fitness-based framework for categorizing existing theories. We show that all theories can be classified into four basic types: secondary (beneficial), maladaptive (neutral), assisted death (detrimental), and senemorphic aging (varying between beneficial to detrimental). We anticipate that this classification system will assist with understanding and interpreting aging/death by providing a way of considering theories as members of one of these classes rather than consideration of their individual details.
Qubit Systems from Colored Toric Geometry and Hypercube Graph Theory*
Aadel, Y.; Belhaj, A.; Bensed, M.; Benslimane, Z.; Sedra, M. B.; Segui, A.
2017-09-01
We develop a new geometric approach to deal with qubit information systems using colored graph theory. More precisely, we present a one to one correspondence between graph theory, and qubit systems, which may be explored to attack qubit information problems using toric geometry considered as a powerful tool to understand modern physics including string theory. Concretely, we examine in some details the cases of one, two, and three qubits, and we find that they are associated with CP 1, CP 1 × CP 1 and CP 1 × CP 1 × CP 1 toric varieties respectively. Using a geometric procedure referred to as a colored toric geometry, we show that the qubit physics can be converted into a scenario handling toric data of such manifolds by help of hypercube graph theory. Operations on toric information can produce universal quantum gates.
Organizational and Systems Theory: An Integrated Review
1980-09-30
because it was this type with which Darwin was concerned in his studies of biological species as systems. Numerous authors--including Ashby (1960), Marney...bases of social power. In D. Cartwright (Ed.), Studies in social ower. Ann Arbor: University of Michigan Institut for Social Research, 1959...N •274 2* 4" * *.* * .*I Guetzkow, H. E. Differentittion of roles in task-oriented tasks. In D. Cartwright , a’ A. Zander (jEds.), GrouT dynamics
Generalized Einstein-Aether theories and the Solar System
Bonvin, Camille; Ferreira, Pedro G; Starkman, Glenn; Zlosnik, Tom G
2007-01-01
It has been shown that generalized Einstein-Aether theories may lead to significant modifications to the non-relativistic limit of the Einstein equations. In this paper we study the effect of a general class of such theories on the Solar System. We consider corrections to the gravitational potential in negative and positive powers of distance from the source. Using measurements of the perihelion shift of Mercury and time delay of radar signals to Cassini, we place constraints on these corrections. We find that a subclass of generalized Einstein-Aether theories are compatible with these constraints.
Comparative index and Sturmian theory for linear Hamiltonian systems
Šepitka, Peter; Šimon Hilscher, Roman
2017-01-01
The comparative index was introduced by J. Elyseeva (2007) as an efficient tool in matrix analysis, which has fundamental applications in the discrete oscillation theory. In this paper we implement the comparative index into the theory of continuous time linear Hamiltonian systems, study its properties, and apply it to obtain new Sturmian separation theorems as well as new and optimal estimates for left and right proper focal points of conjoined bases of these systems on bounded intervals. We derive our results for general possibly abnormal (or uncontrollable) linear Hamiltonian systems. The results turn out to be new even in the case of completely controllable systems. We also provide several examples, which illustrate our new theory.
Asymptotic control theory for a system of linear oscillators
Fedorov, Aleksey; Ovseevich, Alexander
2013-01-01
We present an asymptotic control theory for a system of an arbitrary number of linear oscillators under a common bounded control. We suggest a design method of a feedback control for this system. By using the DiPerna-Lions theory of singular ODEs, we prove that the suggested control law correctly defines the motion of the system. The obtained control is asymptotically optimal: the ratio of the motion time to zero under this control to the minimum one is close to 1 if the initial energy of the...
General System theory, Like-Quantum Semantics and Fuzzy Sets
Licata, Ignazio
2006-01-01
It is outlined the possibility to extend the quantum formalism in relation to the requirements of the general systems theory. It can be done by using a quantum semantics arising from the deep logical structure of quantum theory. It is so possible taking into account the logical openness relationship between observer and system. We are going to show how considering the truth-values of quantum propositions within the context of the fuzzy sets is here more useful for systemics . In conclusion we propose an example of formal quantum coherence.
General exact theory of autoresonance in nonautonomous systems
Chacon, Ricardo
2003-01-01
A general exact theory of autoresonance (self-sustained resonance) in both dissipative and Hamiltonian nonautonomous systems is presented. The equations that together govern the autoresonance solutions and excitations are derived with the aid of a variational principle concerning the power functional. The theory is applied to Duffing oscillators to obtain exact analytical expressions for autoresonance excitations and solutions which explain all the phenomenological and approximate results ari...
MULTI-FLEXIBLE SYSTEM DYNAMIC MODELING THEORY AND APPLICATION
仲昕; 周兵; 杨汝清
2001-01-01
The flexible body modeling theory was demonstrated. An example of modeling a kind of automobile's front suspension as a multi-flexible system was shown. Finally, it shows that the simulation results of multi-flexible dynamic model more approach the road test data than those of multi-rigid dynamic model do. Thus, it is fully testified that using multi-flexible body theory to model is necessary and effective.
Advancing Theory? Landscape Archaeology and Geographical Information Systems
Di Hu
2012-05-01
Full Text Available This paper will focus on how Geographical Information Systems (GIS have been applied in Landscape Archaeology from the late 1980s to the present. GIS, a tool for organising and analysing spatial information, has exploded in popularity, but we still lack a systematic overview of how it has contributed to archaeological theory, specifically Landscape Archaeology. This paper will examine whether and how GIS has advanced archaeological theory through a historical review of its application in archaeology.
Theories about architecture and performance of multi-agent systems
Gazendam, Henk W.M.; Jorna, René J.
1998-01-01
Multi-agent systems are promising as models of organization because they are based on the idea that most work in human organizations is done based on intelligence, communication, cooperation, and massive parallel processing. They offer an alternative for system theories of organization, which are ra
Computer-Based Integrated Learning Systems: Research and Theory.
Hativa, Nira, Ed.; Becker, Henry Jay, Ed.
1994-01-01
The eight chapters of this theme issue discuss recent research and theory concerning computer-based integrated learning systems. Following an introduction about their theoretical background and current use in schools, the effects of using computer-based integrated learning systems in the elementary school classroom are considered. (SLD)
PARADIGMS AND PUZZLES IN THE THEORY OF DYNAMIC-SYSTEMS
WILLEMS, JC
1991-01-01
We will outline the main features of a framework for a theory of dynamical systems. The basic ingredients form a triptych, with the behavior of a system in the center, and behavioral equations and latent variables as side panels. We will discuss a variety of representation and parametrization proble
Beyond Mystification: Reconnecting World-System Theory for Comparative Education.
Clayton, Thomas
1998-01-01
Reviews the literature on world-system theory and critical thinking about class relations to examine differences in thinking about the responses of subordinate actors to hegemony. Suggests an agency-oriented agenda for world-system inquiry in comparative education that focuses on resistance and accommodation by periphery students and educators to…
Confluence of general Schlesinger systems and Twistor theory
Kimura, Hironobu; Tseveennamjil, Damiran
2016-01-01
We give a description of confluence for the general Schlesinger systems (GSS) from the view point of twistor theory. GSS is a system of nonlinear di¤erential equations on the Grassmannian manifold $G_{2,N}(\\mathbf{C}$ which is obtained, for any partition $\\lambda$ of $N$, as the integrability condition of a connection $\
What Should Instructional Designers Know about General Systems Theory?
Salisbury, David F.
1989-01-01
Describes basic concepts in the field of general systems theory (GST) and explains the relationship between instructional systems design (ISD) and GST. Benefits of integrating GST into the curriculum of ISD graduate programs are discussed, and a short bibliography on GST is included. (LRW)
Beyond Mystification: Reconnecting World-System Theory for Comparative Education.
Clayton, Thomas
1998-01-01
Reviews the literature on world-system theory and critical thinking about class relations to examine differences in thinking about the responses of subordinate actors to hegemony. Suggests an agency-oriented agenda for world-system inquiry in comparative education that focuses on resistance and accommodation by periphery students and educators to…
Management Decision Support Systems: From Theory to Practice.
Wong, Simon C. H.
1995-01-01
A decision support system integrates individuals' intellectual resources with computer capabilities to improve decision-making quality. This paper presents the theoretical aspects of decision making and decision support and shows how the theories can be applied in developing an operational management decision-making support system for room booking…
Systems Theory, The Key to Holism and Reductionism
Becht, G.
1974-01-01
The blending of biological and technological knowledge of regulation and control formed the impetus for synthesizing the thesis of holism and the antithesis of reductionism to the metabiological systems theory. In principle, the possibilities have thereby been created to bring many transbiological systems under control again. (RH)
Quantum theory of many-particle systems
Fetter, Alexander L
2003-01-01
""Singlemindedly devoted to its job of educating potential many-particle theorists…deserves to become the standard text in the field."" - Physics Today""The most comprehensive textbook yet published in its field and every postgraduate student or teacher in this field should own or have access to a copy."" - EndeavorA self-contained, unified treatment of nonrelativistic many-particle systems, this text offers a solid introduction to procedures in a manner that enables students to adopt techniques for their own use. Its discussions of formalism and applications move easily between general theo
Representation theory of the system quiver
LI; Longcai(李龙才); ZHANG; Yingbo(张英伯)
2003-01-01
Let A be a three-point algebra with Gabriel quiver the system quiver Q. Then, up to isomorphism and duality, A is tame if and only if A is or degenerates to a factor of a tame algebra in the tame Table T if and only if A/rad5A is tame, and A is wild if and only if A has a wild algebra in the wild Table W as a factor if and only if A is controlled wild.
Theory of skyrmions in bilayer systems
Koshibae, Wataru; Nagaosa, Naoto
2017-02-01
Skyrmion is an emergent particle consisting of many spins in magnets, and has many nontrivial features such as (i) nano-scale size, (ii) topological stability, (iii) gyrodynamics, and (iv) highly efficient spin transfer torque, which make skyrmions the promising candidate for the magnetic devices. Earlier works were focusing on the bulk or thin film of Dzyaloshinskii-Moriya (DM) magnets, while recent advances are focusing on the skyrmions induced by the interfaces. Therefore, the superstructures naturally leads to the interacting skyrmions on different interfaces, which has unique dynamics compared with those on the same interface. Here we theoretically study the two skyrmions on bilayer systems employing micromagnetic simulations as well as the analysis based on Thiele equation, revealing the reaction between them such as the collision and bound state formation. The dynamics depends sensitively on the sign of DM interactions, i.e., helicities, and skyrmion numbers of two skyrmions, which can be well described by Thiele equation. Furthermore, we have found the colossal spin-transfer-torque effect of bound skyrmion pair on antiferromagnetically coupled bilayer systems.
Anthropocentric language theory and Serbian case systems
Topolinjska Zuzana
2002-01-01
Full Text Available The author understands case as a relationship of syntactic dependence between a subordinated noun phrase and the governing syntactic construction (predicative expression and/or another noun phrase. The above definition construes case as a universal category characteristics of all the languages sharing the nomen vs verbum opposition. Particular cases are conceived as primarily semantically motivated. The two relevant semantic parameters are /+/ -human / (or /+/ -animated/ and /+/ -localized/, i. e. - in other words - the so-called hierarchy of animateness and the spatial location of the objects that the corresponding noun phrases refer to. N and D are being characterized as /+ hum/, A and I as /-hum/ and L as belonging to another semantic paradigm is defined simply as /+ loc/. Results of the analyses of morphological syncretism's and of syntactic exponents of the NPs-dependence found in Serbian case systems support the above tentative interpretation of the case as a (semantic and syntactic category.
Lectures on algebraic system theory: Linear systems over rings
Kamen, E. W.
1978-01-01
The presentation centers on four classes of systems that can be treated as linear systems over a ring. These are: (1) discrete-time systems over a ring of scalars such as the integers; (2) continuous-time systems containing time delays; (3) large-scale discrete-time systems; and (4) time-varying discrete-time systems.
The Nature of Living Systems: An Exposition of the Basic Concepts in General Systems Theory.
Miller, James G.
General systems theory is a set of related definitions, assumptions, and propositions which deal with reality as an integrated hierarchy of organizations of matter and energy. In this paper, the author defines the concepts of space, time, matter, energy, and information in terms of their meaning in general systems theory. He defines a system as a…
What is "system" the arguments from the decoherence theory
Dugic, M
1999-01-01
Within the decoherence theory we investigate the physical background of the condition of the separability (diagonalizability in noncorrelated basis) of the interaction Hamiltonian of the composite system, "system plus environment". It proves that the condition of the separability may serve as a criterion for defining "system", but so that "system" cannot be defined unless it is simultaneously defined with its "environment". When extended to a set of the mutually interacting composite systems, this result implies that the separability conditions of the local interactions are mutually tied. The task of defining "system" (and "environment") via investigating the separability of the Hamiltonian is a sort of the inverse task of the decoherence theory. A simple example of doing the task is given.
Product Distribution Theory for Control of Multi-Agent Systems
Lee, Chia Fan; Wolpert, David H.
2004-01-01
Product Distribution (PD) theory is a new framework for controlling Multi-Agent Systems (MAS's). First we review one motivation of PD theory, as the information-theoretic extension of conventional full-rationality game theory to the case of bounded rational agents. In this extension the equilibrium of the game is the optimizer of a Lagrangian of the (probability distribution of) the joint stare of the agents. Accordingly we can consider a team game in which the shared utility is a performance measure of the behavior of the MAS. For such a scenario the game is at equilibrium - the Lagrangian is optimized - when the joint distribution of the agents optimizes the system's expected performance. One common way to find that equilibrium is to have each agent run a reinforcement learning algorithm. Here we investigate the alternative of exploiting PD theory to run gradient descent on the Lagrangian. We present computer experiments validating some of the predictions of PD theory for how best to do that gradient descent. We also demonstrate how PD theory can improve performance even when we are not allowed to rerun the MAS from different initial conditions, a requirement implicit in some previous work.
Open-system Kohn-Sham density functional theory.
Zhou, Yongxi; Ernzerhof, Matthias
2012-03-07
A simple model for electron transport through molecules is provided by the source-sink potential (SSP) method [F. Goyer, M. Ernzerhof, and M. Zhuang, J. Chem. Phys. 126, 144104 (2007)]. In SSP, the boundary conditions of having an incoming and outgoing electron current are enforced through complex potentials that are added to the Hamiltonian. Depending on the sign of the imaginary part of the potentials, current density is generated or absorbed. In this way, a finite system can be used to model infinite molecular electronic devices. The SSP has originally been developed for the Hückel method and subsequently it has been extended [F. Goyer and M. Ernzerhof, J. Chem. Phys. 134, 174101 (2011)] to the Hubbard model. Here we present a step towards its generalization for first-principles electronic structure theory methods. In particular, drawing on our earlier work, we discuss a new generalized density functional theory for complex non-Hermitian Hamiltonians. This theory enables us to combine SSP and Kohn-Sham theory to obtain a method for the description of open systems that exchange current density with their environment. Similarly, the Hartree-Fock method is extended to the realm of non-Hermitian, SSP containing Hamiltonians. As a proof of principle, we present the first applications of complex-density functional theory (CODFT) as well as non-Hermitian Hartree-Fock theory to electron transport through molecules. © 2012 American Institute of Physics
The Einstein-Vlasov System/Kinetic Theory
Andréasson Håkan
2005-01-01
Full Text Available The main purpose of this article is to provide a guide to theorems on global properties of solutions to the Einstein-Vlasov system. This system couples Einsteins equations to a kinetic matter model. Kinetic theory has been an important field of research during several decades in which the main focus has been on nonrelativistic and special relativistic physics, i.e. to model the dynamics of neutral gases, plasmas, and Newtonian self-gravitating systems. In 1990, Rendall and Rein initiated a mathematical study of the Einstein-Vlasov system. Since then many theorems on global properties of solutions to this system have been established. The Vlasov equation describes matter phenomenologically, and it should be stressed that most of the theorems presented in this article are not presently known for other such matter models (i.e. fluid models. This paper gives introductions to kinetic theory in non-curved spacetimes and then the Einstein-Vlasov system is introduced. We believe that a good understanding of kinetic theory in non-curved spacetimes is fundamental to good comprehension of kinetic theory in general relativity.
Systemic Functional Theory: A Pickax of Textual Investigation
Taofeek Dalamu
2017-03-01
Full Text Available The study examines Systemic Functional Theory (SFT as a tool of examining text, and perhaps, text of any dimension as long as it falls within the grammatical organs of the clause. The author provides explanations for the theory from its relevant source(s. The chronological appreciation involves the efforts of Saussure, Firth, Malinowski, Hjelmslev, etc. However, Halliday’s insight seems prominent and upon which Systemic Functional Theory receives a global status that it has assumed today. Halliday constructs numerous concepts e.g. lexicogrammar, processes, cohesion, coherence, system, system network with background from traditional grammar and sociological tokens. In addition to that, the three metafunctions are characterized as its core operational concepts. Out of these, the mood system serves as the instrument of analysis of Psalm one utilized in this endeavor as a case study. Although the clauses fall within the profile of the indicative and imperative, the study reveals that some of the structures are inverted in order to propagate the intended messages. To that end, there are inverted indicative clauses expressed as inverted declarative statements, inverted imperative questions and inverted negativized polarity. In sum, Systemic Functional Theory is a facility for explaining different shapes of texts.
Time delay systems theory, numerics, applications, and experiments
Ersal, Tulga; Orosz, Gábor
2017-01-01
This volume collects contributions related to selected presentations from the 12th IFAC Workshop on Time Delay Systems, Ann Arbor, June 28-30, 2015. The included papers present novel techniques and new results of delayed dynamical systems. The topical spectrum covers control theory, numerical analysis, engineering and biological applications as well as experiments and case studies. The target audience primarily comprises research experts in the field of time delay systems, but the book may also be beneficial for graduate students alike. .
Elements of social representation theory incollaborative tagging systems
Patricia Zeni Marchiori; Andre Luiz Appel; Eduardo Michellotti Bettoni; Denise Fukumi Tsunoda; Frank Coelho de Alcântara
2014-01-01
This article discusses the information representation process based on the Moscovici's Social Representation Theory and domain analysis in Information Science. The aim was to identify mechanisms and constituent dimensions of social representation in collaborative tagging systems/social bookmarking systems. Scientific knowledge was defined as the object/phenomenon of representation in these systems; and the tag as the shareable structure of meaning that connects participants and resources. The...
Hydrodynamics Research on Amphibious Vehicle Systems:Modeling Theory
JU Nai-jun
2006-01-01
For completing the hydrodynamics software development and the engineering application research on the amphibious vehicle systems, hydrodynamic modeling theory of the amphibious vehicle systems is elaborated, which includes to build up the dynamic system model of amphibious vehicle motion on water, gun tracking-aiming-firing, bullet hit and armored check-target, gunner operating control, and the simulation computed model of time domain for random sea wave.
Theory of symmetry for a rotational relativistic Birkhoff system
罗绍凯; 陈向炜; 郭永新
2002-01-01
The theory of symmetry for a rotational relativistic Birkhoff system is studied. In terms of the invariance of therotational relativistic Pfaff-Birkhoff-D'Alembert principle under infinitesimal transformations, the Noether symmetriesand conserved quantities of a rotational relativistic Birkhoff system are given. In terms of the invariance of rotationalrelativistic Birkhoff equations under infinitesimal transformations, the Lie symmetries and conserved quantities of therotational relativistic Birkhoff system are given.
Graphic theory on interval stability of networked control systems
无
2008-01-01
A new method on the interval stability of networked control systems (NCSs) with random delay and data packet dropout is studied. Combining interval systems and NCSs, a graphic condition on judging interval stability is presented in terms of the weighted diagraph theory in graph theory. Furthermore, utilizing the graph-theoretic algorithm, the delay-depended controller gains are obtained. Aiming at the same delay and data packed dropout, several controller gains are obtained, simultaneously. The example and simulation illustrate the effectiveness of the proposed method.
Noether's theory of Lagrange systems in discrete case
Lu Hong-Sheng; Zhang-Hong-Bin; Gu Shu-Long
2011-01-01
In this paper, Noether theory of Lagrange systems in discrete case are studied. First, we briefly overview the wellknown Noether theory of Lagrange system in the continuous case. Then, we introduce some definitions and notations,such as the operators of discrete translation to the right and the left and the operators of discrete differentiation to the right and the left, and give the conditions for the invariance of the difference functional on the uniform lattice and the non-uniform one, respectively. We also deduce the discrete analog of the Noether-type identity. Finally, the discrete analog of Noether's theorem is presented. An example was discussed to illustrate these results.
Network analysis and synthesis a modern systems theory approach
Anderson, Brian D O
2006-01-01
Geared toward upper-level undergraduates and graduate students, this book offers a comprehensive look at linear network analysis and synthesis. It explores state-space synthesis as well as analysis, employing modern systems theory to unite the classical concepts of network theory. The authors stress passive networks but include material on active networks. They avoid topology in dealing with analysis problems and discuss computational techniques. The concepts of controllability, observability, and degree are emphasized in reviewing the state-variable description of linear systems. Explorations
Effective Field Theory for Low-Energy np Systems
Park, T S
1998-01-01
The properties of low-energy neutron-proton systems are studied in an effective field theory where only nucleons figure as relevant degrees of freedom. With a finite momentum cut-off regularization scheme, we show that the large scattering lengths of the np systems do not spoil the convergence of the effective field theory, which turns out to be extremely successful in reproducing, with little cut-off dependence, the deuteron properties, the np 1S0 scattering amplitude and most significantly, the M1 transition amplitude entering into the radiative np capture process.
Kurt Burch
1995-08-01
Full Text Available World system theory comprises two distinct lines of inquiry: macro-social studies of historical world-systems and ideological critique. World system theorists often shun ideological critique, but for two reasons I argue it must be foremost. First, without explicit attention to its philosophical foundations, world system theory rests upon several unexamined, uncomplementary, liberal premises. These premises pose conceptual puzzles. World system theorists frequently cast such puzzles as methodological, empirical, or theoretical problems, rather than as symptoms of ideological confusions requiring critique. Second, through explicit critique, theorists may transform implicit philosophical foundations into explicit ontological and epistemological groundings. Such groundings will enable world system theorists to better realize their critical, emancipatory goals and to resolve theoretical puzzles. One such puzzle -- the conceptual distinction between politics and economics -- recurs often, arising in the debates on the relation(s between the state system and capitalism and thwarting efforts to demonstrate the unity of the world system. I suggest that world system theorists engage in explicit ideological critique to lay equally explicit ideologicalfoundations for their histories. I suggest a critical, conceptually historicist, "constructivist" approach that builds upon postpositivist critiques and introduces constitutive principles. I illustrate the virtue of this approach by demonstrating the unity of the modern world system.
International Summer School on Mathematical Systems Theory and Economics
Szegö, G
1969-01-01
The International Summer School on Mathematical Systems Theory and Economics was held at the Villa Monastero in Varenna, Italy, from June 1 through June 12, 1967. The objective of this Summer School was to review the state of the art and the prospects for the application of the mathematical theory of systems to the study and the solution of economic problems. Particular emphasis was given to the use of the mathematical theory of control for the solution of problems in economics. It was felt that the publication of a volume collecting most of the lectures given at the school would show the current status of the application of these methods. The papers are organized into four sections arranged into two volumes: basic theories and optimal control of economic systems which appear in the first volume, and special mathematical problems and special applications which are contained in the second volume. Within each section the papers follow in alphabetical order by author. The seven papers on basic theories are a rat...
Perspective: Explicitly correlated electronic structure theory for complex systems
Grüneis, Andreas; Hirata, So; Ohnishi, Yu-ya; Ten-no, Seiichiro
2017-02-01
The explicitly correlated approach is one of the most important breakthroughs in ab initio electronic structure theory, providing arguably the most compact, accurate, and efficient ansatz for describing the correlated motion of electrons. Since Hylleraas first used an explicitly correlated wave function for the He atom in 1929, numerous attempts have been made to tackle the significant challenges involved in constructing practical explicitly correlated methods that are applicable to larger systems. These include identifying suitable mathematical forms of a correlated wave function and an efficient evaluation of many-electron integrals. R12 theory, which employs the resolution of the identity approximation, emerged in 1985, followed by the introduction of novel correlation factors and wave function ansätze, leading to the establishment of F12 theory in the 2000s. Rapid progress in recent years has significantly extended the application range of explicitly correlated theory, offering the potential of an accurate wave-function treatment of complex systems such as photosystems and semiconductors. This perspective surveys explicitly correlated electronic structure theory, with an emphasis on recent stochastic and deterministic approaches that hold significant promise for applications to large and complex systems including solids.
Theory of generalized tautology in revised Kleene system
无
2001-01-01
This paper is a complement and extension of the theory of generalized tautology which was first proposed by Wang Guojun in revised Kleene system, Some interesting results are obtained: (i) accessible α+-tautology and generalized contradiction which are dual theory to generalized tautology have been introduced; (ii) congruence partition about has been given in logic system , W, Wk; (iii) in logic system Wk, tautologies can be obtained by employing the upgrade algorithm at most (k+1)/(2) times to an arbitrary formula; (iv) in logic system (W), tautologies cannot be obtained by employing upgrade algorithm to non-tautologies within finitely many times; (v) the deduction rule (1)/(2)+-MP holds in logic system (W).
Information granules and entropy theory in information systems
LIANG JiYe; QIAN YuHua
2008-01-01
Information granulation and entropy theory are two main approaches to research uncertainty of an information system,which have been widely applied in many practical issues.In this paper,the characterizations and representations of information granules under various binary relations are investigated in information systems,an axiom definition of information granulation is presented,and some existing definitions of information granulation become its special forms.Entropy theory in information systems is further developed and the granulation monotonicity of each of them is proved.Moreover,the complement relationship between information granulation and entropy is established.This investigation unifies the results of measures for uncertainties in complete information systems and incomplete information systems.
A mean field theory of coded CDMA systems
Yano, Toru [Graduate School of Science and Technology, Keio University, Hiyoshi, Kohoku-ku, Yokohama-shi, Kanagawa 223-8522 (Japan); Tanaka, Toshiyuki [Graduate School of Informatics, Kyoto University, Yoshida Hon-machi, Sakyo-ku, Kyoto-shi, Kyoto 606-8501 (Japan); Saad, David [Neural Computing Research Group, Aston University, Birmingham B4 7ET (United Kingdom)], E-mail: yano@thx.appi.keio.ac.jp
2008-08-15
We present a mean field theory of code-division multiple-access (CDMA) systems with error-control coding. On the basis of the relation between the free energy and mutual information, we obtain an analytical expression of the maximum spectral efficiency of the coded CDMA system, from which a mean-field description of the coded CDMA system is provided in terms of a bank of scalar Gaussian channels whose variances in general vary at different code symbol positions. Regular low-density parity-check (LDPC)-coded CDMA systems are also discussed as an example of the coded CDMA systems.
Communication and Language in Niklas Luhmann's Systems-Theory
Kathrin Maurer
2010-01-01
Full Text Available This article investigates the function and reality of language in Niklas Luhmann's systems theory. How can one interpret the systems-theoretical assumption that language is based on communication? Luhmann describes language as a dynamic media/form relationship, which is able to couple the social and psychological system. This structural coupling, which constructs consciousness and language as two autonomous systems, raises problems if one defines language from a cognitive point of view. This article discusses these problems and aims to develop assumptions and questions within the systems-theoretical approach.
System, subsystem, hive: boundary problems in computational theories of consciousness
Tomer Fekete
2016-07-01
Full Text Available A computational theory of consciousness should include a quantitative measure of consciousness, or MoC, that (i would reveal to what extent a given system is conscious, (ii would make it possible to compare not only different systems, but also the same system at different times, and (iii would be graded, because so is consciousness. However, unless its design is properly constrained, such an MoC gives rise to what we call the boundary problem: an MoC that labels a system as conscious will do so for some – perhaps most – of its subsystems, as well as for irrelevantly extended systems (e.g., the original system augmented with physical appendages that contribute nothing to the properties supposedly supporting consciousness, and for aggregates of individually conscious systems (e.g., groups of people. This problem suggests that the properties that are being measured are epiphenomenal to consciousness, or else it implies a bizarre proliferation of minds. We propose that a solution to the boundary problem can be found by identifying properties that are intrinsic or systemic: properties that clearly differentiate between systems whose existence is a matter of fact, as opposed to those whose existence is a matter of interpretation (in the eye of the beholder. We argue that if a putative MoC can be shown to be systemic, this ipso facto resolves any associated boundary issues. As test cases, we analyze two recent theories of consciousness in light of our definitions: the Integrated Information Theory and the Geometric Theory of consciousness.
Characterization of Inlet Diffuser Performance for Stratified Thermal Storage
Cimbala, John M.; Bahnfleth, William; Song, Jing
1999-11-01
Storage of sensible heating or cooling capacity in stratified vessels has important applications in central heating and cooling plants, power production, and solar energy utilization, among others. In stratified thermal storage systems, diffusers at the top and bottom of a stratified tank introduce and withdraw fluid while maintaining a stable density gradient and causing as little mixing as possible. In chilled water storage applications, mixing during the formation of the thermocline near an inlet diffuser is the single greatest source of thermal losses. Most stratified chilled water storage tanks are cylindrical vessels with diffusers that are either circular disks that distribute flow radially outward or octagonal rings of perforated pipe that distribute flow both inward and outward radially. Both types produce gravity currents that are strongly influenced by the inlet Richardson number, but the significance of other parameters is not clear. The present investigation considers the dependence of the thermal performance of a perforated pipe diffuser on design parameters including inlet velocity, ambient and inlet fluid temperatures, and tank dimensions for a range of conditions representative of typical chilled water applications. Dimensional analysis is combined with a parametric study using results from computational fluid dynamics to obtain quantitative relationships between design parameters and expected thermal performance.
Nonautonomous linear Hamiltonian systems oscillation, spectral theory and control
Johnson, Russell; Novo, Sylvia; Núñez, Carmen; Fabbri, Roberta
2016-01-01
This monograph contains an in-depth analysis of the dynamics given by a linear Hamiltonian system of general dimension with nonautonomous bounded and uniformly continuous coefficients, without other initial assumptions on time-recurrence. Particular attention is given to the oscillation properties of the solutions as well as to a spectral theory appropriate for such systems. The book contains extensions of results which are well known when the coefficients are autonomous or periodic, as well as in the nonautonomous two-dimensional case. However, a substantial part of the theory presented here is new even in those much simpler situations. The authors make systematic use of basic facts concerning Lagrange planes and symplectic matrices, and apply some fundamental methods of topological dynamics and ergodic theory. Among the tools used in the analysis, which include Lyapunov exponents, Weyl matrices, exponential dichotomy, and weak disconjugacy, a fundamental role is played by the rotation number for linear Hami...
[The kinetic theory of the aging of living systems].
Viktorov, A A; Kholodnov, V A
2013-01-01
Kinetic theory of aging of living systems is proposed. Theory is based on the concept of continuous adaptation of biological system (BS) from its birth to changing conditions of environment (ENV). Adaptation rate as rate of risk of destructions accumulation in BS is studied as competition between two simultaneous processes: BS destruction and recombination of damages defined by kinetics of autocatalytic chemical reactions. Kinetic theory assumes critical phenomenon: failure of adaptation when intensity of ENV impact becomes higher some critical level. Choice of parameters of kinetic mathematical model and accounting dependence of ENV impact intensity on time allows describing the following results observed in medical practice: child mortality, depletion of adaptive reserves, slowing the rate of aging of long-living persons, damped harmonic oscillations of biological response at pulse toxic intervention and to estimate risks of disease and death.
Career Counseling: Applying the Systems Theory Framework of Career Development
McMahon, Mary
2005-01-01
In recent years, career development and career counseling have increasingly been informed by concepts emanating from the constructivist worldview. For example, the Systems Theory Framework (STF; M. McMahon, 2002; M. McMahon & W. Patton, 1995; W. Patton & M. McMahon, 1997, 1999) of career development has been proposed as a metatheoretical account…
Implicit Sociology, Interdisciplinarity and Systems Theories in Agricultural Science
Jansen, K.
2009-01-01
Recurring political and economic crises in agriculture lie behind policymakers' demands for more interdisciplinary, problem-solving approaches. This article examines different systems theories in agricultural sciences that claim to adopt interdisciplinarity and to bridge a supposed gap between the n
[General systems theory, analog models and essential arterial hypertension].
Indovina, I; Bonelli, M
1991-02-15
The application of the General System Theory to the fields of biology and particularly of medicine is fraught with many difficulties deriving from the mathematical complexities of application. The authors suggest that these difficulties can be overcome by applying analogical models, thus opening new prospects for the resolution of the manifold problems involved in connection with the study of arterial hypertension.
A Dynamic Systems Theory Model of Visual Perception Development
Coté, Carol A.
2015-01-01
This article presents a model for understanding the development of visual perception from a dynamic systems theory perspective. It contrasts to a hierarchical or reductionist model that is often found in the occupational therapy literature. In this proposed model vision and ocular motor abilities are not foundational to perception, they are seen…
International Conference on Dynamical Systems : Theory and Applications
2016-01-01
The book is a collection of contributions devoted to analytical, numerical and experimental techniques of dynamical systems, presented at the international conference "Dynamical Systems: Theory and Applications," held in Lódz, Poland on December 7-10, 2015. The studies give deep insight into new perspectives in analysis, simulation, and optimization of dynamical systems, emphasizing directions for future research. Broadly outlined topics covered include: bifurcation and chaos in dynamical systems, asymptotic methods in nonlinear dynamics, dynamics in life sciences and bioengineering, original numerical methods of vibration analysis, control in dynamical systems, stability of dynamical systems, vibrations of lumped and continuous sytems, non-smooth systems, engineering systems and differential equations, mathematical approaches to dynamical systems, and mechatronics.
International Conference on Dynamical Systems : Theory and Applications
2016-01-01
The book is the second volume of a collection of contributions devoted to analytical, numerical and experimental techniques of dynamical systems, presented at the international conference "Dynamical Systems: Theory and Applications," held in Lódz, Poland on December 7-10, 2015. The studies give deep insight into new perspectives in analysis, simulation, and optimization of dynamical systems, emphasizing directions for future research. Broadly outlined topics covered include: bifurcation and chaos in dynamical systems, asymptotic methods in nonlinear dynamics, dynamics in life sciences and bioengineering, original numerical methods of vibration analysis, control in dynamical systems, stability of dynamical systems, vibrations of lumped and continuous sytems, non-smooth systems, engineering systems and differential equations, mathematical approaches to dynamical systems, and mechatronics.
Geometrical Field Theory of Hamilton Dynamic System In Rational Mechanics
Jianhua, Xiao
2011-01-01
When a set of particles are moving in a potential field, two aspects are concerned: 1) the relative motion of particle in spatial domain; 2) the particle velocity variations in time domain. The difficulty on treating the systems is originated from the fact that the motion in time domain and the motion in spatial domain are coupled together completely. Generally, for a Hamilton dynamic system established by a set of general velocity functions, several abstract theories have been well established, such as Lie algebra, Symplectic manifold, Poisson brackets, and others. However, mathematically, to find out a general Hamilton function is very difficult even for very simple problems. Inspired by these abstract mathematic researches, the Hamilton dynamic system is studied by geometrical field theory of deformation. Firstly, referring to the instant configuration, the deformation tensor in spatial domain and the velocity transformation tensor in time domain are established for a dynamic system defined by a set of gen...
Global analysis theory of climate system and its applications
无
2003-01-01
The idea and main theoretical results of the global analysis theory of climate system are briefly summarized in this paper. A theorem on the global behavior of climate system is given, i.e. there exists a global attractor in the dynamical equations of climate, any state of climate system will be evolved into the global attractor as time increases, indicating the nonlinear adjustment process of climate system to external forcing. The different effects of external forcing, dissipation and nonlinearity on the long-term behavior of solutions are pointed out, and some main applications of the global analysis theory are also introduced. Especially, three applications, the adjustment and evolution processes of climate, the principle of numerical model design and the optimally numerical integration, are discussed.
Complex Time-Delay Systems Theory and Applications
Atay, Fatihcan M
2010-01-01
Time delays in dynamical systems arise as an inevitable consequence of finite speeds of information transmission. Realistic models increasingly demand the inclusion of delays in order to properly understand, analyze, design, and control real-life systems. The goal of this book is to present the state-of-the-art in research on time-delay dynamics in the framework of complex systems and networks. While the mathematical theory of delay equations is quite mature, its application to the particular problems of complex systems and complexity is a newly emerging field, and the present volume aims to play a pioneering role in this perspective. The chapters in this volume are authored by renowned experts and cover both theory and applications in a wide range of fields, with examples extending from neuroscience and biology to laser physics and vehicle traffic. Furthermore, all chapters include sufficient introductory material and extensive bibliographies, making the book a self-contained reference for both students and ...
Lucarini, Valerio
2010-05-01
We consider the general response theory recently proposed by Ruelle for describing the impact of small perturbations to the non-equilibrium steady states resulting from Axiom A dynamical systems. We show that the causality of the response functions entails the possibility of writing a set of Kramers-Kronig (K-K) relations for the corresponding susceptibilities at all orders of nonlinearity, and specific results are provided for the case of arbitrary order harmonic response. These results shed light on the very general impact of considering the principle of causality for testing self-consistency: the described dispersion relations constitute unavoidable benchmarks that any experimental and model generated dataset must obey. These results, taking into account the chaotic hypothesis by Gallavotti and Cohen, might be relevant in several fields, including climate research. In particular, whereas the fluctuation-dissipation theorem does not work for non-equilibrium systems, because of the non-equivalence between internal and external fluctuations, K-K relations might be robust tools for the definition of a self-consistent theory of climate change. Along these lines, we present here the first evidence of the validity of these integral relations for the linear and the second harmonic response for the perturbed Lorenz 63 system, by showing that numerical simulations agree up to high degree of accuracy with the theoretical predictions. The numerical results confirm the conceptual validity of the nonlinear response theory, suggest that the theory can be extended for more general non equilibrium steady state systems, and shed new light on the applicability of very general tools, based only upon the principle of causality, for diagnosing the behavior of perturbed chaotic systems and reconstructing their output signals.
Hegemonic Stability Theories of the International Monetary System
Eichengreen, Barry
1987-01-01
Specialists in international relations have argued that international regimes operate smoothly and exhibit stability only when dominated by a single, exceptionally powerful national economy. In particular, this "theory of hegemonic stability" has been applied to the international monetary system. The maintenance of the Bretton Woods System for a quarter of a century up to 1972 is ascribed to the singular power of the United States in the postwar world, while the persistence of the classical g...
The concept of hierarchy in general systems theory.
Gasparski, W
1994-01-01
The paper reviews main ideas related to the concept of hierarchy as they are discussed in contemporary general systems theory. After presenting a dictionary definition of the concept, the author examines the intuitive idea of hierarchy quoting Mario Bunge's notion of level structure. Then relationship between two other concepts: a system and a hierarchy is characterised on the bases of Bowler's, Bunge's again, Klir's, and the author's studies. Finally, the paper is concluded that hierarchy is not an otological concept but epistemological one.
Theory of ground state factorization in quantum cooperative systems.
Giampaolo, Salvatore M; Adesso, Gerardo; Illuminati, Fabrizio
2008-05-16
We introduce a general analytic approach to the study of factorization points and factorized ground states in quantum cooperative systems. The method allows us to determine rigorously the existence, location, and exact form of separable ground states in a large variety of, generally nonexactly solvable, spin models belonging to different universality classes. The theory applies to translationally invariant systems, irrespective of spatial dimensionality, and for spin-spin interactions of arbitrary range.
The emergence of information systems: a communication-based theory
Holten, Roland; Rosenkranz, Christoph
2012-01-01
An information system is more than just the information technology; it is the system that emerges from the complex interactions and relationships between the information technology and the organization. However, what impact information technology has on an organization and how organizational structures and organizational change influence information technology remains an open question. We propose a theory to explain how communication structures emerge and adapt to environmental changes. We op...
Randomized Algorithms for Systems and Control: Theory and Applications
2008-05-01
IEIIT-CNR Randomized Algorithms for Systems and Control: Theory and Applications NATO LS Glasgow, Pamplona , Cleveland @RT 2008 Roberto Tempo IEIIT...Glasgow, Pamplona , Cleveland @RT 2008 roberto.tempo@polito.it IEIIT-CNR References R. Tempo, G. Calafiore and F. Dabbene, “Randomized Algorithms for...Analysis and Control of Uncertain Systems,” Springer-Verlag, London, 2005 R Tempo and H Ishii “Monte Carlo and Las Vegas NATO LS Glasgow, Pamplona , Cleveland
Chemical reaction network approaches to Biochemical Systems Theory.
Arceo, Carlene Perpetua P; Jose, Editha C; Marin-Sanguino, Alberto; Mendoza, Eduardo R
2015-11-01
This paper provides a framework to represent a Biochemical Systems Theory (BST) model (in either GMA or S-system form) as a chemical reaction network with power law kinetics. Using this representation, some basic properties and the application of recent results of Chemical Reaction Network Theory regarding steady states of such systems are shown. In particular, Injectivity Theory, including network concordance [36] and the Jacobian Determinant Criterion [43], a "Lifting Theorem" for steady states [26] and the comprehensive results of Müller and Regensburger [31] on complex balanced equilibria are discussed. A partial extension of a recent Emulation Theorem of Cardelli for mass action systems [3] is derived for a subclass of power law kinetic systems. However, it is also shown that the GMA and S-system models of human purine metabolism [10] do not display the reactant-determined kinetics assumed by Müller and Regensburger and hence only a subset of BST models can be handled with their approach. Moreover, since the reaction networks underlying many BST models are not weakly reversible, results for non-complex balanced equilibria are also needed.
Analysis of system trustworthiness based on information flow noninterference theory
Xiangying Kong; Yanhui Chen; Yi Zhuang
2015-01-01
The trustworthiness analysis and evaluation are the bases of the trust chain transfer. In this paper the formal method of trustworthiness analysis of a system based on the noninterfer-ence (NI) theory of the information flow is studied. Firstly, existing methods cannot analyze the impact of the system states on the trustworthiness of software during the process of trust chain trans-fer. To solve this problem, the impact of the system state on trust-worthiness of software is investigated, the run-time mutual interfer-ence behavior of software entities is described and an interference model of the access control automaton of a system is established. Secondly, based on the intransitive noninterference (INI) theory, a formal analytic method of trustworthiness for trust chain transfer is proposed, providing a theoretical basis for the analysis of dynamic trustworthiness of software during the trust chain transfer process. Thirdly, a prototype system with dynamic trustworthiness on a plat-form with dual core architecture is constructed and a verification algorithm of the system trustworthiness is provided. Final y, the monitor hypothesis is extended to the dynamic monitor hypothe-sis, a theorem of static judgment rule of system trustworthiness is provided, which is useful to prove dynamic trustworthiness of a system at the beginning of system construction. Compared with previous work in this field, this research proposes not only a formal analytic method for the determination of system trustworthiness, but also a modeling method and an analysis algorithm that are feasible for practical implementation.
Solar system constraints on some Horndeski gravity theories
Bhattacharya, Sourav
2016-01-01
We discuss two spherically symmetric solutions admitted by the Horndeski (or scalar tensor) theory in the context of solar system physics. One of these solutions is derived for Einstein-Gauss-Bonnet gravity, while the other originates from the coupling of the Gauss-Bonnet invariant with a scalar field. Specifically, we discuss the perihelion precession of the Mercury and the bending angle of light for these two different spherically symmetric spacetimes derived in arXiv hep-th/0611188 and 1408.1698 respectively. Numerical bounds on relevant parameters of these theories from such computations are also presented.
Equivalent sample theory of networked control systems and its application
无
2008-01-01
The equivalent sample theory and its application in analysis of networked control system (NCS) are presented. After analyzing NCS's scheduling in master-slave mode, the characteristics of time delay and sample are summarized. Looking on master station visiting the slave station as a special sample process, the theory of equivalent sample is presented. And based on it, the stability of a kind of NCS is analyzed. The criterion to determine the upper bound of transmission delay is introduced, which guarantees the stability. Finally, an example with simulation shows the availability and usability of this analysis method.
Theory and model of water resources complex adaptive allocation system
ZHAOJianshi; WANGZhongjing; WENGWenbin
2003-01-01
Complex adaptive system theory is a new and important embranchment of system science,which provides a new thought to research water resources allocation system.Based on the analysis of complexity and complex adaptive mechanism of water resources allocation system,a fire-new analysis model is presented in this paper.With the description of Dynamical mechanism of system,behavior characters of agents and the evalustion method of system status,an integrity research system is built to analyse the evolvement rule of water resources allocation system.And a brief research for the impact of water resources allocation in beneficial regions of the Water Transfer from south to North China Project is conducted.
Guillemin, Ernst A
2013-01-01
An eminent electrical engineer and authority on linear system theory presents this advanced treatise, which approaches the subject from the viewpoint of classical dynamics and covers Fourier methods. This volume will assist upper-level undergraduates and graduate students in moving from introductory courses toward an understanding of advanced network synthesis. 1963 edition.
Stably stratified magnetized stars in general relativity
Yoshida, Shijun; Shibata, Masaru
2012-01-01
We construct magnetized stars composed of a fluid stably stratified by entropy gradients in the framework of general relativity, assuming ideal magnetohydrodynamics and employing a barotropic equation of state. We first revisit basic equations for describing stably-stratified stationary axisymmetric stars containing both poloidal and toroidal magnetic fields. As sample models, the magnetized stars considered by Ioka and Sasaki (2004), inside which the magnetic fields are confined, are modified to the ones stably stratified. The magnetized stars newly constructed in this study are believed to be more stable than the existing relativistic models because they have both poloidal and toroidal magnetic fields with comparable strength, and magnetic buoyancy instabilities near the surface of the star, which can be stabilized by the stratification, are suppressed.
Honing Theory: A Complex Systems Framework for Creativity
Gabora, Liane
2016-01-01
This paper proposes a theory of creativity, referred to as honing theory, which posits that creativity fuels the process by which culture evolves through communal exchange amongst minds that are self-organizing, self-maintaining, and self-reproducing. According to honing theory, minds, like other selforganizing systems, modify their contents and adapt to their environments to minimize entropy. Creativity begins with detection of high psychological entropy material, which provokes uncertainty and is arousalinducing. The creative process involves recursively considering this material from new contexts until it is sufficiently restructured that arousal dissipates. Restructuring involves neural synchrony and dynamic binding, and may be facilitated by temporarily shifting to a more associative mode of thought. A creative work may similarly induce restructuring in others, and thereby contribute to the cultural evolution of more nuanced worldviews. Since lines of cultural descent connecting creative outputs may exhi...
Modeling Reusable and Interoperable Faceted Browsing Systems with Category Theory.
Harris, Daniel R
2015-08-01
Faceted browsing has become ubiquitous with modern digital libraries and online search engines, yet the process is still difficult to abstractly model in a manner that supports the development of interoperable and reusable interfaces. We propose category theory as a theoretical foundation for faceted browsing and demonstrate how the interactive process can be mathematically abstracted. Existing efforts in facet modeling are based upon set theory, formal concept analysis, and lightweight ontologies, but in many regards, they are implementations of faceted browsing rather than a specification of the basic, underlying structures and interactions. We will demonstrate that category theory allows us to specify faceted objects and study the relationships and interactions within a faceted browsing system. Implementations can then be constructed through a category-theoretic lens using these models, allowing abstract comparison and communication that naturally support interoperability and reuse.
ADAPTIVE SYSTEMS THEORY: SOME BASIC CONCEPTS, METHODS AND RESULTS
GUO Lei
2003-01-01
The adaptive systems theory to be presented in this paper consists of two closely related parts: adaptive estimation (or filtering, prediction) and adaptive control of dynamical systems. Both adaptive estimation and control are nonlinear mappings of the on-line observed signals of dynamical systems, where the main features are the uncertainties in both the system's structure and external disturbances, and the non-stationarity and dependency of the system signals. Thus, a key difficulty in establishing a mathematical theory of adaptive systems lies in how to deal with complicated nonlinear stochastic dynamical systems which describe the adaptation processes. In this paper, we will illustrate some of the basic concepts, methods and results through some simple examples. The following fundamental questions will be discussed: How much information is needed for estimation? How to deal with uncertainty by adaptation? How to analyze an adaptive system? What are the convergence or tracking performances of adaptation? How to find the proper rate of adaptation in some sense? We will also explore the following more fundamental questions: How much uncertainty can be dealt with by adaptation ? What are the limitations of adaptation ? How does the performance of adaptation depend on the prior information ? We will partially answer these questions by finding some "critical values" and establishing some "Impossibility Theorems" for the capability of adaptation, for several basic classes of nonlinear dynamical control systems with either parametric or nonparametric uncertainties.
Control for Wind Power Generation Based on Inverse System Theory
Jiyong Zhang
2013-11-01
Full Text Available Traditional Double-fed Wind Generation systems are based on the vector control method, and it is dependent on motor parameters. The performance of the control system will be affected with the parameters changing,. This paper proposes a new control method based on inverse system and variable structure sliding mode(VSS theories, through the inverse system theory, the structure of its state’s equation, obtaining the structure of the inverse system, the establishment of Wind Power Generation closed-loop control system is established. The VSS controller, designed with exponential reaching law, can improve the dynamic performance in normal operation range effectively. When the system operates with variable speed constant frequency (VSCF and the phase voltage drops, the simulations show that the control system can control the DC link voltage steabily, maintain unity power factor, achieve the decoupling of the active and reactive power. And experiments show that the control method used in VSCF wind power system is feasible.
Multi-point cooperative communication systems theory and applications
Ding, Ming
2013-01-01
Multi-point Cooperative Communication Systems: Theory and Applications mainly discusses multi-point cooperative communication technologies which are used to overcome the long-standing problem of limited transmission rate caused by the inter-point interference. Instead of combating the interference, recent progress in both academia and industrial standardizations has evolved to adopt the philosophy of “exploiting” the interference to improve the transmission rate by cooperating among multiple points. This book addresses the multi-point cooperative communication system systematically giving the readers a clear picture of the technology map and where the discussed schemes may fit. This book includes not only the theories of the paradigm-shifting multi-point cooperative communication, but also the designs of sub-optimal cooperative communication schemes for practical systems. Ming Ding is a senior researcher at Sharp Laboratories of China; Hanwen Luo is a professor at Shanghai Jiao Tong University.
Energy flow theory of nonlinear dynamical systems with applications
Xing, Jing Tang
2015-01-01
This monograph develops a generalised energy flow theory to investigate non-linear dynamical systems governed by ordinary differential equations in phase space and often met in various science and engineering fields. Important nonlinear phenomena such as, stabilities, periodical orbits, bifurcations and chaos are tack-led and the corresponding energy flow behaviors are revealed using the proposed energy flow approach. As examples, the common interested nonlinear dynamical systems, such as, Duffing’s oscillator, Van der Pol’s equation, Lorenz attractor, Rössler one and SD oscillator, etc, are discussed. This monograph lights a new energy flow research direction for nonlinear dynamics. A generalised Matlab code with User Manuel is provided for readers to conduct the energy flow analysis of their nonlinear dynamical systems. Throughout the monograph the author continuously returns to some examples in each chapter to illustrate the applications of the discussed theory and approaches. The book can be used as ...
Thermals in stratified regions of the ISM
Rodriguez-Gonzalez, Ary
2013-01-01
We present a model of a "thermal" (i.e., a hot bubble) rising within an exponentially stratified region of the ISM. This model includes terms representing the ram pressure braking and the entrainment of environmental gas into the thermal. We then calibrate the free parameters associated with these two terms through a comparison with 3D numerical simulations of a rising bubble. Finally, we apply our "thermal" model to the case of a hot bubble produced by a SN within the stratified ISM of the Galactic disk.
On Stratified Vortex Motions under Gravity.
2014-09-26
AD-A156 930 ON STRATIFIED VORTEX MOTIONS UNDER GRAVITY (U) NAVAL i/i RESEARCH LAB WASHINGTON DC Y T FUNG 20 JUN 85 NRL-MIR-5564 UNCLASSIFIED F/G 20/4...Under Gravity LCn * Y. T. Fung Fluid Dynamics Branch - Marine Technologyv Division June 20, 1985 SO Cyk. NAVAL RESEARCH LABORATORY Washington, D.C...DN880-019 TITLE (Include Security Classification) On Stratified Vortex Motions Under Gravity 12 PERSONAL AUTHOR(S) Funa, Y.T. 13a. TYPE OF REPORT 13b
Mixing by microorganisms in stratified fluids
Wagner, Gregory L; Lauga, Eric
2014-01-01
We examine the vertical mixing induced by the swimming of microorganisms at low Reynolds and P\\'eclet numbers in a stably stratified ocean, and show that the global contribution of oceanic microswimmers to vertical mixing is negligible. We propose two approaches to estimating the mixing efficiency, $\\eta$, or the ratio of the rate of potential energy creation to the total rate-of-working on the ocean by microswimmers. The first is based on scaling arguments and estimates $\\eta$ in terms of the ratio between the typical organism size, $a$, and an intrinsic length scale for the stratified flow, $\\ell = \\left ( \
THERMALS IN STRATIFIED REGIONS OF THE ISM
A. Rodríguez-González
2013-01-01
Full Text Available We present a model of a “thermal” (i.e., a hot bubble rising within an exponentially stratified region of the ISM. This model includes terms representing the ram pressure braking and the entrainment of environmental gas into the thermal. We then calibrate the free parameters associated with these two terms through a comparison with 3D numerical simulations of a rising bubble. Finally, we apply our “thermal” model to the case of a hot bubble produced by a SN within the stratified ISM of the Galactic disk.
Zone of Proximal Development (ZPD) as an Emergent System: A Dynamic Systems Theory Perspective.
Karimi-Aghdam, Saeed
2017-03-01
This paper sets out to present a novel construal of one of the notions of Vygotskian cultural-historical theory viz., zone of proximal development (ZPD) drawing upon dynamic systems theory. The principal thesis maintains that ZDP is an emergent and dynamic system which is engendered by a dialectical concatenation of psychogenesic and sociogenesic facets of human development over time. It is reasoned that Vygotskian cultural-historical theory of human development, by invoking dialectical logic, has transcended Cartesian substance dualism and in turn has proffered a monistic and process-anchored ontology for emerging becoming of human consciousness. Likewise, it is contended that dynamic systems theory, having assumed fluent flux of reality with a capital R as its ontological axiom, entails a consilience of cognitive and contextual conceptual schemes to describe, explain, and optimize human development. The paper concludes by drawing some interpretive conclusions in regard to ZPD from dynamic systems theory perspective.
Theory of constraints for publicly funded health systems.
Sadat, Somayeh; Carter, Michael W; Golden, Brian
2013-03-01
Originally developed in the context of publicly traded for-profit companies, theory of constraints (TOC) improves system performance through leveraging the constraint(s). While the theory seems to be a natural fit for resource-constrained publicly funded health systems, there is a lack of literature addressing the modifications required to adopt TOC and define the goal and performance measures. This paper develops a system dynamics representation of the classical TOC's system-wide goal and performance measures for publicly traded for-profit companies, which forms the basis for developing a similar model for publicly funded health systems. The model is then expanded to include some of the factors that affect system performance, providing a framework to apply TOC's process of ongoing improvement in publicly funded health systems. Future research is required to more accurately define the factors affecting system performance and populate the model with evidence-based estimates for various parameters in order to use the model to guide TOC's process of ongoing improvement.
System of Systems Approach in Production: Theory to Action
Mahmood, Asif
2014-01-01
System of Systems (SoS) is a novel approach in practical field which has been widely studied and applied recognizably in military context by department of defense (DoD). But being versatile, the approach has a lot of potential to deliver in various other areas as well, for example, it is now on the verge to transcend the boundaries of defense system, and ready to be applied in industrial sector. This manuscript based dissertation mainly investigates and explores the last phrased facet, and of...
Theory and applications of artificial endocrine system-an overview
CUI Wei; QIANG Sheng; GAO X Z
2006-01-01
Inspired by the biological endocrine system, the Artificial Endocrine System (AES) has been proposed and investigated during the past decade. As a novel branch of computational intelligence methods, it has its unique and distinguishing features. This paper intends to give an overview of the current research work in the AES. The preliminary theory of the AES, which is based on the simplified mathematic models of natural endocrine system, is first introduced here. Some typical AES algorithms and their applications are also briefly discussed. Finally, a few remarks and conclusions are made.
The theory and practice of the Dewey Decimal Classification system
Satija, M P
2013-01-01
The Dewey Decimal Classification system (DDC) is the world's most popular library classification system. The 23rd edition of the DDC was published in 2011. This second edition of The Theory and Practice of the Dewey Decimal Classification System examines the history, management and technical aspects of the DDC up to its latest edition. The book places emphasis on explaining the structure and number building techniques in the DDC and reviews all aspects of subject analysis and number building by the most recent version of the DDC. A history of, and introduction to, the DDC is followed by subjec
Application of Grey System Theory to tree growth prediction
王晶; 侯月松; 李伟林; 成文惠
2000-01-01
Based on Grey System theory, tree growth prediction models are developed by using 202 temporary plots and 206 stem analysis trees of Dahurian larch (Larix gemlinii Rupr.) in 10 forestry bureaus of Yakeshi Forestry Administrative Bureau in Daxing'an Mountains of the Inner Mongolia Autonomous Region. By residual and posterior tests, their precisions are qualified. With several data, tree growth can be predicted using Grey System models. For DBH and volume, the fitting results of Grey System models are better than that of statistical models.
Poultry Diseases Expert System using Dempster-Shafer Theory
Maseleno, Andino
2012-01-01
Based on World Health Organization (WHO) fact sheet in the 2011, outbreaks of poultry diseases especially Avian Influenza in poultry may raise global public health concerns due to their effect on poultry populations, their potential to cause serious disease in people, and their pandemic potential. In this research, we built a Poultry Diseases Expert System using Dempster-Shafer Theory. In this Poultry Diseases Expert System We describe five symptoms which include depression, combs, wattle, bluish face region, swollen face region, narrowness of eyes, and balance disorders. The result of the research is that Poultry Diseases Expert System has been successfully identifying poultry diseases.
Theory and simulation of strong correlations in quantum Coulomb systems
Bonitz, M; Filinov, A V; Golubnychiy, V O; Kremp, D; Gericke, D O; Murillo, M S; Filinov, V S; Fortov, V; Hoyer, W; Koch, S W
2003-01-01
Strong correlations in quantum Coulomb systems (QCS) are attracting increasing interest in many fields ranging from dense plasmas and semiconductors to metal clusters and ultracold trapped ions. Examples are bound states in dense plasmas (atoms, molecules, clusters) and semiconductors (excitons, trions, biexcitons) or Coulomb crystals. We present first-principle simulation results of these systems including path integral Monte Carlo simulations of the equilibrium behaviour of dense hydrogen and electron-hole plasmas and molecular dynamics and quantum kinetic theory simulations of the nonequilibrium properties of QCS. Finally, we critically assess potential and limitations of the various methods in their application to Coulomb systems.
Vladimir Lefebvre's Theory of Two Systems of Ethical Cognition
Stuart A. Umpleby
2016-10-01
Full Text Available In his 1982 book Algebra of Conscience Vladimir Lefebvre contended that the dominant ethical systems in the West and the Soviet Union were fundamentally different [1]. However, people on each side usually assume that there is only one type of ethical reasoning. The result is that each side takes actions that are misunderstood by the other side. With the guidance of Lefebvre's theory it became possible for both sides to take actions which, although counterintuitive in their own thinking, could lead to more success in negotiations and a reduction in armaments. Luckily, Lefebvre's theory was used at the highest levels of the governments of the US and the Soviet Union during the break-up of the Soviet Union. Lefebvre's theory can be used in negotiations between governments, between businesses, and between individuals. The theory explains some of the difficulties encountered in the transitions in the post-communist countries. It may also prove helpful in negotiating with extremist groups. [1] V. Lefebvre, Algebra of Conscience: A Comparative Analysis of Western and Soviet Ethical Systems, With a forword by Anatol Rapoport, Dordrecht, Holland: D. Reidel Publishing, 1982.
Realistic theory of electronic correlations in nanoscopic systems
Schüler, Malte; Barthel, Stefan; Wehling, Tim; Karolak, Michael; Valli, Angelo; Sangiovanni, Giorgio
2017-07-01
Nanostructures with open shell transition metal or molecular constituents host often strong electronic correlations and are highly sensitive to atomistic material details. This tutorial review discusses method developments and applications of theoretical approaches for the realistic description of the electronic and magnetic properties of nanostructures with correlated electrons. First, the implementation of a flexible interface between density functional theory and a variant of dynamical mean field theory (DMFT) highly suitable for the simulation of complex correlated structures is explained and illustrated. On the DMFT side, this interface is largely based on recent developments of quantum Monte Carlo and exact diagonalization techniques allowing for efficient descriptions of general four fermion Coulomb interactions, reduced symmetries and spin-orbit coupling, which are explained here. With the examples of the Cr (001) surfaces, magnetic adatoms, and molecular systems it is shown how the interplay of Hubbard U and Hund's J determines charge and spin fluctuations and how these interactions drive different sorts of correlation effects in nanosystems. Non-local interactions and correlations present a particular challenge for the theory of low dimensional systems. We present our method developments addressing these two challenges, i.e., advancements of the dynamical vertex approximation and a combination of the constrained random phase approximation with continuum medium theories. We demonstrate how non-local interaction and correlation phenomena are controlled not only by dimensionality but also by coupling to the environment which is typically important for determining the physics of nanosystems.
Williams, Nathaniel J; Glisson, Charles
2014-04-01
Theories of organizational culture and climate (OCC) applied to child welfare systems hypothesize that strategic dimensions of organizational culture influence organizational climate and that OCC explains system variance in youth outcomes. This study provides the first structural test of the direct and indirect effects of culture and climate on youth outcomes in a national sample of child welfare systems and isolates specific culture and climate dimensions most associated with youth outcomes. The study applies multilevel path analysis (ML-PA) to a U.S. nationwide sample of 2,380 youth in 73 child welfare systems participating in the second National Survey of Child and Adolescent Well-being. Youths were selected in a national, two-stage, stratified random sample design. Youths' psychosocial functioning was assessed by caregivers' responses to the Child Behavior Checklist at intake and at 18-month follow-up. OCC was assessed by front-line caseworkers' (N=1,740) aggregated responses to the Organizational Social Context measure. Comparison of the a priori and subsequent trimmed models confirmed a reduced model that excluded rigid organizational culture and explained 70% of the system variance in youth outcomes. Controlling for youth- and system-level covariates, systems with more proficient and less resistant organizational cultures exhibited more functional, more engaged, and less stressful climates. Systems with more proficient cultures and more engaged, more functional, and more stressful climates exhibited superior youth outcomes. Findings suggest child welfare administrators can support service effectiveness with interventions that improve specific dimensions of culture and climate.
Geometric Theory for the Design of Multielement Optical Systems
无
2001-01-01
To establish a theoretical basis for providing a better design method of multielement optical systems, we have developed a third-order geometric theory of a plane-symmetric multielement optical system that consists of a planar light source, an arbitrary number of ellipsoidal gratings, and an image plane. Analytic formulas of spot diagrams are derived for the system by analytically following a ray-tracing formalism. With these formulas, coma, spherical aberration, and resultant aberration are discussed. To make the theory practical, we determine the aberration coefficients numerically, rather than analytically, with the aid of ray tracing that takes into account the angular distribution of rays originating from a given light source. A merit function is defined so as to represent closely the variance of the spots formed when an infinite number of rays are traced and to take into account the dimensions of the source and the last optical element. The theory is also applicable to mirror-grating or mirror systems.
Quantum theory of many-body systems techniques and applications
Zagoskin, Alexandre
2014-01-01
This text presents a self-contained treatment of the physics of many-body systems from the point of view of condensed matter. The approach, quite traditionally, uses the mathematical formalism of quasiparticles and Green’s functions. In particular, it covers all the important diagram techniques for normal and superconducting systems, including the zero-temperature perturbation theory and the Matsubara, Keldysh and Nambu-Gor'kov formalism, as well as an introduction to Feynman path integrals. This new edition contains an introduction to the methods of theory of one-dimensional systems (bosonization and conformal field theory) and their applications to many-body problems. Intended for graduate students in physics and related fields, the aim is not to be exhaustive, but to present enough detail to enable the student to follow the current research literature, or to apply the techniques to new problems. Many of the examples are drawn from mesoscopic physics, which deals with systems small enough that quantum...
[Theories of biological evolution from the viewpoint of the modern systemic biology].
Lashin, S A; Suslov, V V; Matushkin, Iu G
2012-05-01
Theories of biological evolution advanced in the last 200 years are reviewed from the viewpoint of advances of modern genetics. The theory of gene networks as a key direction of systemic biology is a link connecting different evolutionary theories.
A Systematic Review of Literature Using Business Systems Theory
Rana, Mohammad Bakhtiar; Morgan, Glenn
2015-01-01
Business system theory (BST) lies at the intersection of organization theory, political economy and sociology. It is gaining incremental attention in the field of management, particularly in cross-border and comparative studies of the structure, strategy and management of multinationals. Yet......, international business (IB) studies do not tend to borrow much from this sub-field. This paper reviews BST literature from 1992 to 2015 and seeks to identify its contributions and gaps, in ways that can be helpful for future research in IB. Trend analysis of BST literature and mapping this sub-field suggests...... that the BST research stream can be identified in relation to four ‘broad themes’ which we describe as junctures- i.e. comparative business systems, internationalisation and MNC management, organizational capability and innovation, and transnational communities. Mapping and pattern recognition of the ‘themes...
Complex geometric optics for symmetric hyperbolic systems I: linear theory
Maj, Omar
2008-01-01
We obtain an asymptotic solution for $\\ep \\to 0$ of the Cauchy problem for linear first-order symmetric hyperbolic systems with oscillatory initial values written in the eikonal form of geometric optics with frequency $1/\\ep$, but with complex phases. For the most common linear wave propagation models, this kind on Cauchy problems are well-known in the applied literature and their asymptotic theory, referred to as complex geometric optics, is attracting interest for applications. In this work, which is the first of a series of papers dedicated to complex geometric optics for nonlinear symmetric hyperbolic systems, we develop a rigorous linear theory and set the basis for the subsequent nonlinear analysis.
A Systematic Review of Literature Using Business Systems Theory
Rana, Mohammad Bakhtiar; Morgan, Glenn
2015-01-01
Business system theory (BST) lies at the intersection of organization theory, political economy and sociology. It is gaining incremental attention in the field of management, particularly in cross-border and comparative studies of the structure, strategy and management of multinationals. Yet...... that the BST research stream can be identified in relation to four ‘broad themes’ which we describe as junctures- i.e. comparative business systems, internationalisation and MNC management, organizational capability and innovation, and transnational communities. Mapping and pattern recognition of the ‘themes......’ focused in BST literature show that the highest focus of publications is on the study of internationalisation and the structure, strategy and management of multinationals. International business studies, particularly that using neo- and new-institutionalism as a framework have much to learn from the BST...
Perturbation theory calculations of model pair potential systems
Gong, Jianwu [Iowa State Univ., Ames, IA (United States)
2016-01-01
Helmholtz free energy is one of the most important thermodynamic properties for condensed matter systems. It is closely related to other thermodynamic properties such as chemical potential and compressibility. It is also the starting point for studies of interfacial properties and phase coexistence if free energies of different phases can be obtained. In this thesis, we will use an approach based on the Weeks-Chandler-Anderson (WCA) perturbation theory to calculate the free energy of both solid and liquid phases of Lennard-Jones pair potential systems and the free energy of liquid states of Yukawa pair potentials. Our results indicate that the perturbation theory provides an accurate approach to the free energy calculations of liquid and solid phases based upon comparisons with results from molecular dynamics (MD) and Monte Carlo (MC) simulations.
Continuous and distributed systems II theory and applications
Zgurovsky, Mikhail
2015-01-01
As in the previous volume on the topic, the authors close the gap between abstract mathematical approaches, such as applied methods of modern algebra and analysis, fundamental and computational mechanics, nonautonomous and stochastic dynamical systems, on the one hand, and practical applications in nonlinear mechanics, optimization, decision making theory and control theory on the other. Readers will also benefit from the presentation of modern mathematical modeling methods for the numerical solution of complicated engineering problems in biochemistry, geophysics, biology and climatology. This compilation will be of interest to mathematicians and engineers working at the interface of these fields. It presents selected works of the joint seminar series of Lomonosov Moscow State University and the Institute for Applied System Analysis at National Technical University of Ukraine “Kyiv Polytechnic Institute”. The authors come from Brazil, Germany, France, Mexico, Spain, Poland, Russia, Ukraine, and the USA. ...
Turbulent Mixing in Stably Stratified Flows
2008-03-01
Liege Colloquium on Ocean Hydrodynamics, volume 46, page 19889898. Elsevier, 1987. R. M. Kerr. Higher-order derivative correlations and the alignment of...19th International Liege Colloquium on Ocean Hydrodynamics, volume 46, pages 3-9. Elsevier, 1988. P. Meunier and G. Spedding. Stratified propelled
Stability of steam-water countercurrent stratified flow
Lee, S C
1985-10-01
Two flow instabilities which limit the normal condensation processes in countercurrent stratified steam-water flow have been identified experimentally: flooding and condensation-induced waterhammer. In order to initiate condensation-induced waterhammer in nearly horizontal or moderately-inclined steam/subcooled-water flow, two conditions, the appearance of a wavy interface and complete condensation of the incoming steam, are necessary. Analyses of these conditions are performed on a basis of flow stability and heat transfer considerations. Flooding data for several inclinations and channel heights are collected. Effects of condensation, inclination angle and channel height on the flooding characteristics are discussed. An envelope theory for the onset of flooding in inclined stratified flow is developed, which agrees well with the experimental data. Some empirical information on basic flow parameters, such as mean film thickness and interfacial friction factor required for this theory are measured. The previous viewpoints on flooding appear not to conflict with the present experimental data in nearly horizontal flow but the flooding phenomena in nearly vertical flow appear to be more complicated than those described by these viewpoints because of liquid droplet entrainment.
Transition Theory – Sustainable Transition of Socio-Technical Systems
Søndergård, Bent; Holm, Jesper; Stauning, Inger
2015-01-01
Theories of transition management, transition studies and social practise theory Applied to studies of hosuing and construction......Theories of transition management, transition studies and social practise theory Applied to studies of hosuing and construction...
Brillouin-Wigner perturbation theory in open electromagnetic systems
Muljarov, E A; Zimmermann, R; 10.1209/0295-5075/92/50010
2012-01-01
A Brillouin-Wigner perturbation theory is developed for open electromagnetic systems which are characterised by discrete resonant states with complex eigenenergies. Since these states are exponentially growing at large distances, a modified normalisation is introduced that allows a simple spectral representation of the Green's function. The perturbed modes are found by solving a linear eigenvalue problem in matrix form. The method is illustrated on exactly solvable one- and three-dimensional examples being, respectively, a dielectric slab and a microsphere.
On the role of complexity in systems theory
Greben, JM
2009-01-01
Full Text Available with perfect symmetry and zero entropy. Due to the vacuum metric the efiective energy density is inflnite at the beginning, but diminishes rapidly. Once it reaches the Planck energy density of elementary particles, the formation of particles can commence... assumptions. The evolution of the universe in this theory has rather deflnite characteristics, with some of the details still to be developed. Contrary to most popular scenarios, the universe starts out as a classical system, with an efiective energy...
Y-system for $\\gamma$-deformed ABJM Theory
Chen, Hui-Huang; Wu, Jun-Bao
2016-01-01
We investigate the integrable aspects of the planar $\\gamma$-deformed ABJM theory and proposed the twisted asymptotic Bethe ansatz equations. A more general method through a twist generating functional was discussed, based on which, the asymptotic large L solution of Y-system is modified in order to match the asymptotic Bethe ansatz equations. Serval applications of our method were made in $sl(2)$ sector and some important examples in $\\beta$-deformed ABJM were present as well.
CONCEPTS OF GENERAL SYSTEMS THEORY APPLIED ON GOODS
Bogdan Onete
2007-01-01
The General Systems Theory is one of the most important points of view nowadays. Now, its concepts could be applied in a various number of sciences including Consumer Sciences. The complexity of the product, the different way in which it can be seen and also the exponentially diversifying assortment requires another approach to the product, through models. This approach must take into account certain particularities which do not appear in a regular modelling
The benchmark of gutzwiller density functional theory in hydrogen systems
Yao, Y.; Wang, Cai-Zhuang; Ho, Kai-Ming
2012-02-23
We propose an approximate form of the exchange-correlation energy functional for the Gutzwiller density functional theory. It satisfies certain physical constraints in both weak and strong electron correlation limits. We benchmark the Gutzwiller density functional approximation in the hydrogen systems, where the static correlation error is shown to be negligible. The good transferability is demonstrated by applications to the hydrogen molecule and some crystal structures.
The Benchmark of Gutzwiller Density Functional Theory in Hydrogen Systems
Yao, Yongxin; Wang, Cai-Zhuang; Ho, Kai-Ming
2011-01-13
We propose an approximate form of the exchange-correlation energy functional for the Gutzwiller density functional theory. It satisfies certain physical constraints in both weak and strong electron correlation limits. We benchmark the Gutzwiller density functional approximation in the hydrogen systems, where the static correlation error is shown to be negligible. The good transferability is demonstrated by applications to the hydrogen molecule and some crystal structures. © 2011 Wiley Periodicals, Inc. Int J Quantum Chem, 2012
Miller, Todd S.; Bugliosi, Edward F.
2013-01-01
In 2002, the U.S. Geological Survey, in cooperation with the Tompkins County Planning Department and the Town of Dryden, New York, began a study of the stratified-drift aquifer system in the Virgil Creek and Dryden Lake Valleys in the Town of Dryden, Tompkins County. The study provided geohydrologic data needed by the town and county to develop a strategy to manage and protect their water resources. In this study area, three extensive confined sand and gravel aquifers (the upper, middle, and lower confined aquifers) compose the stratified-drift aquifer system. The Dryden Lake Valley is a glaciated valley oriented parallel to the direction of ice movement. Erosion by ice extensively widened and deepened the valley, truncated bedrock hillsides, and formed a nearly straight, U-shaped bedrock trough. The maximum thickness of the valley fill in the central part of the valley is about 400 feet (ft). The Virgil Creek Valley in the east part of the study area underwent less severe erosion by ice than the Dryden Lake Valley, and hence, it has a bedrock floor that is several hundred feet higher in altitude than that in the Dryden Lake Valley. The sources and amounts of recharge were difficult to identify in most areas because the confined aquifers are overlain by confining units. However, in the vicinity of the Virgil Creek Dam, the upper confined aquifer crops out at land surface in the floodplain of a gorge eroded by Virgil Creek, and this is where the aquifer receives large amounts of recharge from precipitation that directly falls over the aquifer and from seepage losses from Virgil Creek. The results of streamflow measurements made in Virgil Creek where it flows through the gorge indicated that the stream lost 1.2 cubic feet per second (ft3/s) or 0.78 million gallons per day (Mgal/d) of water in the reach extending from 220 ft downstream from the dam to 1,200 ft upstream from the dam. In the southern part of the study area, large amounts of recharge also replenish the
Helicity dynamics in stratified turbulence in the absence of forcing
Rorai, C; Pouquet, A; Mininni, P D
2012-01-01
A numerical study of decaying stably-stratified flows is performed. Relatively high stratification and moderate Reynolds numbers are considered, and a particular emphasis is placed on the role of helicity (velocity-vorticity correlations). The problem is tackled by integrating the Boussinesq equations in a periodic cubical domain using different initial conditions: a non-helical Taylor-Green (TG) flow, a fully helical Beltrami (ABC) flow, and random flows with a tunable helicity. We show that for stratified ABC flows helicity undergoes a substantially slower decay than for unstratified ABC flows. This fact is likely associated to the combined effect of stratification and large scale coherent structures. Indeed, when the latter are missing, as in random flows, helicity is rapidly destroyed by the onset of gravitational waves. A type of large-scale dissipative "cyclostrophic" balance can be invoked to explain this behavior. When helicity survives in the system it strongly affects the temporal energy decay and t...
Lectures on Supersymmetric Yang-Mills Theory and Integrable Systems
D'Hoker, Eric; Phong, D. H.
Introduction Supersymmetry and the Standard Model Supersymmetry and Unification of Forces Supersymmetric Yang-Mills Dynamics Supersymmetric Yang-Mills in 4 Dimensions Supersymmetry Algebra Massless Particle Representations Massive Particle Representations Field Contents of Supersymmetric Field Theories N = 1 Supersymmetric Lagrangians N = 1 Superfield Methods Irreducible Superfields of N = 1 General N = 1 Susy Lagrangians via Superfields Renormalizable N = 2,4 Susy Lagrangians N = 2 Superfield Methods: Unconstrained Superspace N = 2 Superfield Methods: Harmonic/Analytic Superspaces Seiberg-Witten Theory Wilson Effective Couplings and Actions Holomorphicity and Nonrenormalization Low Energy Dynamics of N = 2 Super-Yang-Mills Particle and Field Contents Form of the N = 2 Low Energy Effective Lagrangian Physical Properties of the Prepotential Electric-Magnetic Duality Monodromy via Elliptic Curves for SU(2) Gauge Group Physical Interpretation of Singularities Hypergeometric Function Representation More General Gauge Groups, Hypermultiplets Model of Riemann Surfaces Identifying Seiberg-Witten and Riemann Surface Data SU(N) Gauge Algebras, Fundamental Hypermultiplets Classical Gauge Algebras, Fundamental Hypermultiplets Mechanical Integrable Systems Lax Pairs with Spectral Parameter-Spectral Curves The Toda Systems The Calogero-Moser Systems for SU(N) Relation between Calogero-Moser and Toda for SU(N) Relations with KdV and KP Systems Calogero-Moser Systems for General Lie Algebras Scaling of Calogero-Moser to Toda for General Lie Algebras Calogero-Moser Lax Pairs for General Lie Algebras Lax Pairs with Spectral Parameter for Classical Lie Algebras The General Ansatz Lax Pairs for Untwisted Calogero-Moser Systems Lax Pairs for Twisted Calogero-Moser Systems Scaling Limits of Lax Pairs Super-Yang-Mills and Calogero-Moser Systems Correspondence of Seiberg-Witten and Integrable Systems Calogero-Moser and Seiberg-Witten Theory for SU(N) Four Fundamental Theorems Partial
Correlations in complex nonlinear systems and quantum information theory
Guehne, Otfried [Institut fuer Quantenoptik und Quanteninformation, Oesterreichische Akademie der Wissenschaften, Innsbruck (Austria); Galla, Tobias [School of Physics and Astronomy, University of Manchester (United Kingdom)
2010-07-01
The dynamical evolution of classical complex systems such as coupled logistic maps or simple models of lattice gases and cellular automata can result in correlations between distant parts of the system. For the understanding of these systems, it is crucial to develop methods to characterize and quantify these multi-party correlations. On the other hand, the study of correlations between distant particles is also a central problem in the field of quantum information theory. There, correlations are often viewed as a resource and many tools have been developed for their characterization. In this talk, we explore the extent to which the tools from quantum information can be applied to study classical complex systems and whether they allow to study complex systems from a different perspective.
Synthesis of Systemic Functional Theory & Dynamical Systems Theory for Socio-Cultural Modeling
2012-05-07
audio resources, requires a range of tools for the annotation, analysis, search and retrieval of semantic patterns in unified but complex semiotic ...unit and linking it to another annotation unit. The links themselves are annotated using system choices for inter- semiotic relations. Automated...linguistic analysis. These are key system choices in the inter- semiotic discoursal structure for visual images and language. The larger pattern count of 73
[General systems theory, a mental frame for geriatric psychiatry].
Lit, A C
1984-12-01
Though psychogeriatrics is becoming a word of common usage, it is not a word of common meaning. This is a consequence of the lack of a generally accepted theoretical model regarding the complex and multiple pathology of the psychiatric disturbances of older people. On epistemological grounds the author stresses the necessity of a common theoretical concept and as such introduces the General System Theory. The systems approach then shows that the word 'psychogeriatrics' is rooted in a reductionistic concept of man. In order to avoid this the author prefers 'psychiatry of old age' to cover the broad field of the psychiatric disturbances of the elderly.
Rapid Occupant Classification System Based Rough Sets Theory
Lin Chen
2012-09-01
Full Text Available In the intelligent airbag system, the correct classification of occupant type is the precondition and plays an important role in controlling the airbag release time and inflation strength during emergent accidents. In the paper, the novel rapid occupant classification system is proposed in which tens of pressure sensors are needed to real-time collect pressure distribution data and then the rough sets theory is combined to extract classification knowledge from data features. Furthermore, Experiments have been done to verify its efficiency and effectiviness.
A first course in chaotic dynamical systems theory and experiment
Devaney, Robert L
1992-01-01
This is the first book to introduce modern topics in dynamical systems at the undergraduate level. Accessible to readers with only a background in calculus, the book integrates both theory and computer experiments into its coverage of contemporary ideas in dynamics. It is designed as a gradual introduction to the basic mathematical ideas behind such topics as chaos, fractals, Newton's method, symbolic dynamics, the Julia set, and the Mandelbrot set, and includes biographies of some of the leading researchers in the field of dynamical systems. Mathematical and computer experiments are integrate
Game Theory and Risk-Based Levee System Design
Hui, R.; Lund, J. R.; Madani, K.
2014-12-01
Risk-based analysis has been developed for optimal levee design for economic efficiency. Along many rivers, two levees on opposite riverbanks act as a simple levee system. Being rational and self-interested, land owners on each river bank would tend to independently optimize their levees with risk-based analysis, resulting in a Pareto-inefficient levee system design from the social planner's perspective. Game theory is applied in this study to analyze decision making process in a simple levee system in which the land owners on each river bank develop their design strategies using risk-based economic optimization. For each land owner, the annual expected total cost includes expected annual damage cost and annualized construction cost. The non-cooperative Nash equilibrium is identified and compared to the social planner's optimal distribution of flood risk and damage cost throughout the system which results in the minimum total flood cost for the system. The social planner's optimal solution is not feasible without appropriate level of compensation for the transferred flood risk to guarantee and improve conditions for all parties. Therefore, cooperative game theory is then employed to develop an economically optimal design that can be implemented in practice. By examining the game in the reversible and irreversible decision making modes, the cost of decision making myopia is calculated to underline the significance of considering the externalities and evolution path of dynamic water resource problems for optimal decision making.
Review and application of group theory to molecular systems biology
Rietman Edward A
2011-06-01
Full Text Available Abstract In this paper we provide a review of selected mathematical ideas that can help us better understand the boundary between living and non-living systems. We focus on group theory and abstract algebra applied to molecular systems biology. Throughout this paper we briefly describe possible open problems. In connection with the genetic code we propose that it may be possible to use perturbation theory to explore the adjacent possibilities in the 64-dimensional space-time manifold of the evolving genome. With regards to algebraic graph theory, there are several minor open problems we discuss. In relation to network dynamics and groupoid formalism we suggest that the network graph might not be the main focus for understanding the phenotype but rather the phase space of the network dynamics. We show a simple case of a C6 network and its phase space network. We envision that the molecular network of a cell is actually a complex network of hypercycles and feedback circuits that could be better represented in a higher-dimensional space. We conjecture that targeting nodes in the molecular network that have key roles in the phase space, as revealed by analysis of the automorphism decomposition, might be a better way to drug discovery and treatment of cancer.
Review and application of group theory to molecular systems biology.
Rietman, Edward A; Karp, Robert L; Tuszynski, Jack A
2011-06-22
In this paper we provide a review of selected mathematical ideas that can help us better understand the boundary between living and non-living systems. We focus on group theory and abstract algebra applied to molecular systems biology. Throughout this paper we briefly describe possible open problems. In connection with the genetic code we propose that it may be possible to use perturbation theory to explore the adjacent possibilities in the 64-dimensional space-time manifold of the evolving genome. With regards to algebraic graph theory, there are several minor open problems we discuss. In relation to network dynamics and groupoid formalism we suggest that the network graph might not be the main focus for understanding the phenotype but rather the phase space of the network dynamics. We show a simple case of a C6 network and its phase space network. We envision that the molecular network of a cell is actually a complex network of hypercycles and feedback circuits that could be better represented in a higher-dimensional space. We conjecture that targeting nodes in the molecular network that have key roles in the phase space, as revealed by analysis of the automorphism decomposition, might be a better way to drug discovery and treatment of cancer.
Effective field theories for superconducting systems with multiple Fermi surfaces
Braga, P. R.; Granado, D. R.; Guimaraes, M. S.; Wotzasek, C.
2016-11-01
In this work we investigate the description of superconducting systems with multiple Fermi surfaces. For the case of one Fermi surface we re-obtain the result that the superconductor is more precisely described as a topological state of matter. Studying the case of more than one Fermi surface, we obtain the effective theory describing a time reversal symmetric topological superconductor. These results are obtained by employing a general procedure to construct effective low energy actions describing states of electromagnetic systems interacting with charges and defects. The procedure consists in taking into account the proliferation or dilution of these charges and defects and its consequences for the low energy description of the electromagnetic response of the system. We find that the main ingredient entering the low energy characterization of the system with more than one Fermi surface is a non-conservation of the canonical supercurrent triggered by particular vortex configurations.
Effective field theories for superconducting systems with multiple Fermi surfaces
Braga, P R; Guimaraes, M S; Wotzasek, C
2016-01-01
In this work we investigate the description of superconducting systems with multiple Fermi surfaces. For the case of one Fermi surface we re-obtain the result that the superconductor is more precisely described as a topological state of matter. Studying the case of more than one Fermi surface, we obtain the effective theory describing a time reversal symmetric topological superconductor. These results are obtained by employing a general procedure to construct effective low energy actions describing states of electromagnetic systems interacting with charges and defects. The procedure consists in taking into account the proliferation or dilution of these charges and defects and its consequences for the low energy description of the electromagnetic response of the system. We find that the main ingredient entering the low energy characterization of the system with more the one Fermi surface is a non-conservation of the canonical supercurrent triggered by particular vortex configurations.
Effective field theories for superconducting systems with multiple Fermi surfaces
Braga, P.R., E-mail: pedro.rangel.braga@gmail.com [Departamento de Física Teórica, Instituto de Física, UERJ - Universidade do Estado do Rio de Janeiro, Rua São Francisco Xavier 524, 20550-013 Maracanã, Rio de Janeiro (Brazil); Granado, D.R., E-mail: diegorochagrana@uerj.br [Departamento de Física Teórica, Instituto de Física, UERJ - Universidade do Estado do Rio de Janeiro, Rua São Francisco Xavier 524, 20550-013 Maracanã, Rio de Janeiro (Brazil); Department of Physics and Astronomy, Ghent University, Krijgslaan 281-S9, 9000 Gent (Belgium); Guimaraes, M.S., E-mail: msguimaraes@uerj.br [Departamento de Física Teórica, Instituto de Física, UERJ - Universidade do Estado do Rio de Janeiro, Rua São Francisco Xavier 524, 20550-013 Maracanã, Rio de Janeiro (Brazil); Wotzasek, C., E-mail: clovis@if.ufrj.br [Instituto de Física, Universidade Federal do Rio de Janeiro, 21941-972, Rio de Janeiro (Brazil)
2016-11-15
In this work we investigate the description of superconducting systems with multiple Fermi surfaces. For the case of one Fermi surface we re-obtain the result that the superconductor is more precisely described as a topological state of matter. Studying the case of more than one Fermi surface, we obtain the effective theory describing a time reversal symmetric topological superconductor. These results are obtained by employing a general procedure to construct effective low energy actions describing states of electromagnetic systems interacting with charges and defects. The procedure consists in taking into account the proliferation or dilution of these charges and defects and its consequences for the low energy description of the electromagnetic response of the system. We find that the main ingredient entering the low energy characterization of the system with more than one Fermi surface is a non-conservation of the canonical supercurrent triggered by particular vortex configurations.
Classical and Quantum Nonlinear Integrable Systems: Theory and Application
Brzezinski, Tomasz [Department of Mathematics, University of Wales Swansea (United Kingdom)
2003-12-12
This is a very interesting collection of introductory and review articles on the theory and applications of classical and quantum integrable systems. The book reviews several integrable systems such as the KdV equation, vertex models, RSOS and IRF models, spin chains, integrable differential equations, discrete systems, Ising, Potts and other lattice models and reaction--diffusion processes, as well as outlining major methods of solving integrable systems. These include Lax pairs, Baecklund and Miura transformations, the inverse scattering method, various types of the Bethe Ansatz, Painleve methods, the dbar method and fusion methods to mention just a few. The book is divided into two parts, each containing five chapters. The first part is devoted to classical integrable systems and introduces the subject through the KdV equation, and then proceeds through Painleve analysis, discrete systems and two-dimensional integrable partial differential equations, to culminate in the review of solvable lattice models in statistical physics, solved through the coordinate and algebraic Bethe Ansatz methods. The second part deals with quantum integrable systems, and begins with an outline of unifying approaches to quantum, statistical, ultralocal and non-ultralocal systems. The theory and methods of solving quantum integrable spin chains are then described. Recent developments in applying Bethe Ansatz methods in condensed matter physics, including superconductivity and nanoscale physics, are reviewed. The book concludes with an introduction to diffusion-reaction processes. Every chapter is devoted to a different subject and is self-contained, and thus can be read separately. A reader interesting in classical methods of solitons, such as the methods of solving the KdV equation, can start from Chapter 1, while a reader interested in the Bethe Ansatz method can immediately proceed to Chapter 5, and so on. Thus the book should appeal and be useful to a wide range of theoretical
Random matrix theory for pseudo-Hermitian systems: Cyclic blocks
Sudhir R Jain; Shashi C L Srivastava
2009-12-01
We discuss the relevance of random matrix theory for pseudo-Hermitian systems, and, for Hamiltonians that break parity and time-reversal invariance . In an attempt to understand the random Ising model, we present the treatment of cyclic asymmetric matrices with blocks and show that the nearest-neighbour spacing distributions have the same form as obtained for the matrices with scalar entries. We also summarize the theory for random cyclic matrices with scalar entries. We have also found that for block matrices made of Hermitian and pseudo-Hermitian sub-blocks of the form appearing in Ising model depart from the known results for scalar entries. However, there is still similarity in trends even in log–log plots.
The application of information theory to biochemical signaling systems.
Rhee, Alex; Cheong, Raymond; Levchenko, Andre
2012-08-01
Cell signaling can be thought of fundamentally as an information transmission problem in which chemical messengers relay information about the external environment to the decision centers within a cell. Due to the biochemical nature of cellular signal transduction networks, molecular noise will inevitably limit the fidelity of any messages received and processed by a cell's signal transduction networks, leaving it with an imperfect impression of its environment. Fortunately, Shannon's information theory provides a mathematical framework independent of network complexity that can quantify the amount of information that can be transmitted despite biochemical noise. In particular, the channel capacity can be used to measure the maximum number of stimuli a cell can distinguish based upon the noisy responses of its signaling systems. Here, we provide a primer for quantitative biologists that covers fundamental concepts of information theory, highlights several key considerations when experimentally measuring channel capacity, and describes successful examples of the application of information theoretic analysis to biological signaling.
Bridging emotion theory and neurobiology through dynamic systems modeling.
Lewis, Marc D
2005-04-01
Efforts to bridge emotion theory with neurobiology can be facilitated by dynamic systems (DS) modeling. DS principles stipulate higher-order wholes emerging from lower-order constituents through bidirectional causal processes--offering a common language for psychological and neurobiological models. After identifying some limitations of mainstream emotion theory, I apply DS principles to emotion-cognition relations. I then present a psychological model based on this reconceptualization, identifying trigger, self-amplification, and self-stabilization phases of emotion-appraisal states, leading to consolidating traits. The article goes on to describe neural structures and functions involved in appraisal and emotion, as well as DS mechanisms of integration by which they interact. These mechanisms include nested feedback interactions, global effects of neuromodulation, vertical integration, action-monitoring, and synaptic plasticity, and they are modeled in terms of both functional integration and temporal synchronization. I end by elaborating the psychological model of emotion-appraisal states with reference to neural processes.
Regularity theory for mean-field game systems
Gomes, Diogo A; Voskanyan, Vardan
2016-01-01
Beginning with a concise introduction to the theory of mean-field games (MFGs), this book presents the key elements of the regularity theory for MFGs. It then introduces a series of techniques for well-posedness in the context of mean-field problems, including stationary and time-dependent MFGs, subquadratic and superquadratic MFG formulations, and distinct classes of mean-field couplings. It also explores stationary and time-dependent MFGs through a series of a-priori estimates for solutions of the Hamilton-Jacobi and Fokker-Planck equation. It shows sophisticated a-priori systems derived using a range of analytical techniques, and builds on previous results to explain classical solutions. The final chapter discusses the potential applications, models and natural extensions of MFGs. As MFGs connect common problems in pure mathematics, engineering, economics and data management, this book is a valuable resource for researchers and graduate students in these fields.
Multicomponent and multiscale systems theory, methods, and applications in engineering
Geiser, Juergen
2016-01-01
This book examines the latest research results from combined multi-component and multi-scale explorations. It provides theory, considers underlying numerical methods, and presents brilliant computational experimentation. Engineering computations featured in this monograph further offer particular interest to many researchers, engineers, and computational scientists working in frontier modeling and applications of multicomponent and multiscale problems. Professor Geiser gives specific attention to the aspects of decomposing and splitting delicate structures and controlling decomposition and the rationale behind many important applications of multi-component and multi-scale analysis. Multicomponent and Multiscale Systems: Theory, Methods, and Applications in Engineering also considers the question of why iterative methods can be powerful and more appropriate for well-balanced multiscale and multicomponent coupled nonlinear problems. The book is ideal for engineers and scientists working in theoretical and a...
Coherent control of quantum systems as a resource theory
Matera, J. M.; Egloff, D.; Killoran, N.; Plenio, M. B.
2016-08-01
Control at the interface between the classical and the quantum world is fundamental in quantum physics. In particular, how classical control is enhanced by coherence effects is an important question both from a theoretical as well as from a technological point of view. In this work, we establish a resource theory describing this setting and explore relations to the theory of coherence, entanglement and information processing. Specifically, for the coherent control of quantum systems, the relevant resources of entanglement and coherence are found to be equivalent and closely related to a measure of discord. The results are then applied to the DQC1 protocol and the precision of the final measurement is expressed in terms of the available resources.
Quantum tomography meets dynamical systems and bifurcations theory
Goyeneche, D., E-mail: dardo.goyeneche@cefop.udec.cl [Departamento de Fisíca, Universidad de Concepción, Casilla 160-C, Concepción, Chile and Center for Optics and Photonics, Universidad de Concepción, Casilla 4012, Concepción (Chile); Torre, A. C. de la [Departamento de Física, Universidad Nacional de Mar del Plata, IFIMAR-CONICET, Dean Funes 3350, 7600 Mar del Plata (Argentina)
2014-06-01
A powerful tool for studying geometrical problems in Hilbert spaces is developed. We demonstrate the convergence and robustness of our method in every dimension by considering dynamical systems theory. This method provides numerical solutions to hard problems involving many coupled nonlinear equations in low and high dimensions (e.g., quantum tomography problem, existence and classification of Pauli partners, mutually unbiased bases, complex Hadamard matrices, equiangular tight frames, etc.). Additionally, this tool can be used to find analytical solutions and also to implicitly prove the existence of solutions. Here, we develop the theory for the quantum pure state tomography problem in finite dimensions but this approach is straightforwardly extended to the rest of the problems. We prove that solutions are always attractive fixed points of a nonlinear operator explicitly given. As an application, we show that the statistics collected from three random orthonormal bases is enough to reconstruct pure states from experimental (noisy) data in every dimension d ⩽ 32.
Regularity Theory for Mean-Field Game Systems
Gomes, Diogo A.
2016-09-14
Beginning with a concise introduction to the theory of mean-field games (MFGs), this book presents the key elements of the regularity theory for MFGs. It then introduces a series of techniques for well-posedness in the context of mean-field problems, including stationary and time-dependent MFGs, subquadratic and superquadratic MFG formulations, and distinct classes of mean-field couplings. It also explores stationary and time-dependent MFGs through a series of a-priori estimates for solutions of the Hamilton-Jacobi and Fokker-Planck equation. It shows sophisticated a-priori systems derived using a range of analytical techniques, and builds on previous results to explain classical solutions. The final chapter discusses the potential applications, models and natural extensions of MFGs. As MFGs connect common problems in pure mathematics, engineering, economics and data management, this book is a valuable resource for researchers and graduate students in these fields.
Stability of stratified two-phase flows in horizontal channels
Barmak, I.; Gelfgat, A.; Vitoshkin, H.; Ullmann, A.; Brauner, N.
2016-04-01
Linear stability of stratified two-phase flows in horizontal channels to arbitrary wavenumber disturbances is studied. The problem is reduced to Orr-Sommerfeld equations for the stream function disturbances, defined in each sublayer and coupled via boundary conditions that account also for possible interface deformation and capillary forces. Applying the Chebyshev collocation method, the equations and interface boundary conditions are reduced to the generalized eigenvalue problems solved by standard means of numerical linear algebra for the entire spectrum of eigenvalues and the associated eigenvectors. Some additional conclusions concerning the instability nature are derived from the most unstable perturbation patterns. The results are summarized in the form of stability maps showing the operational conditions at which a stratified-smooth flow pattern is stable. It is found that for gas-liquid and liquid-liquid systems, the stratified flow with a smooth interface is stable only in confined zone of relatively low flow rates, which is in agreement with experiments, but is not predicted by long-wave analysis. Depending on the flow conditions, the critical perturbations can originate mainly at the interface (so-called "interfacial modes of instability") or in the bulk of one of the phases (i.e., "shear modes"). The present analysis revealed that there is no definite correlation between the type of instability and the perturbation wavelength.
Information System Development Model: Theories Analysis and Guidelines
Nayan, Norshita Mat; Badioze Zaman, Halimah
Development of information system project is one of the IT projects which have been developed to offer the best facilities for publics. Process of system development will go through its own life cycle and every process must be refined in order to fulfill aims and objectives. Eventhough information system development is always correlate with failure but a few key factors will help the systems to succeed. There are multiple success factors being discussed by other researches in the information system development but failure figure still at the higher side. The main purpose of this research is to discuss processes involved in the development of information system which positively contribute towards its success. Model of information system development which has been developed (PADM Model) consists of four fundamental processes; planning, requirement analysis, design and maintenance. All processes will be monitored by a main process namely quality as the key performance indicator. Quality plays a vital role in assessing the ability of information system developed in order to fulfill users' expectations. Analysis of theory can be used as a guideline and measurement base towards the system with hope that percentage of failure will reduce subsequently.
Vector dissipativity theory for large-scale impulsive dynamical systems
Haddad Wassim M.
2004-01-01
Full Text Available Modern complex large-scale impulsive systems involve multiple modes of operation placing stringent demands on controller analysis of increasing complexity. In analyzing these large-scale systems, it is often desirable to treat the overall impulsive system as a collection of interconnected impulsive subsystems. Solution properties of the large-scale impulsive system are then deduced from the solution properties of the individual impulsive subsystems and the nature of the impulsive system interconnections. In this paper, we develop vector dissipativity theory for large-scale impulsive dynamical systems. Specifically, using vector storage functions and vector hybrid supply rates, dissipativity properties of the composite large-scale impulsive systems are shown to be determined from the dissipativity properties of the impulsive subsystems and their interconnections. Furthermore, extended Kalman-Yakubovich-Popov conditions, in terms of the impulsive subsystem dynamics and interconnection constraints, characterizing vector dissipativeness via vector system storage functions, are derived. Finally, these results are used to develop feedback interconnection stability results for large-scale impulsive dynamical systems using vector Lyapunov functions.
A unified theory for systems and cellular memory consolidation.
Dash, Pramod K; Hebert, April E; Runyan, Jason D
2004-04-01
The time-limited role of the hippocampus for explicit memory storage has been referred to as systems consolidation where learning-related changes occur first in the hippocampus followed by the gradual development of a more distributed memory trace in the neocortex. Recent experiments are beginning to show that learning induces plasticity-related molecular changes in the neocortex as well as in the hippocampus and with a similar time course. Present memory consolidation theories do not account for these findings. In this report, we present a theory (the C theory) that incorporates these new findings, provides an explanation for the length of time for hippocampal dependency, and that can account for the apparent longer consolidation periods in species with larger brains. This theory proposes that a process of cellular consolidation occurs in the hippocampus and in areas of the neocortex during and shortly after learning resulting in long-term memory storage in both areas. For a limited time, the hippocampus is necessary for memory retrieval, a process involving the coordinated reactivation of these areas. This reactivation is later mediated by longer extrahippocampal connectivity between areas. The delay in hippocampal-independent memory retrieval is the time it takes for gene products in these longer extrahippocampal projections to be transported from the soma to tagged synapses by slow axonal transport. This cellular transport event defines the period of hippocampal dependency and, thus, the duration of memory consolidation. The theoretical description for memory consolidation presented in this review provides alternative explanations for several experimental observations and presents a unification of the concepts of systems and cellular memory consolidation.
Nonlinear closure relations theory for transport processes in nonequilibrium systems.
Sonnino, Giorgio
2009-05-01
A decade ago, a macroscopic theory for closure relations has been proposed for systems out of Onsager's region. This theory is referred to as the thermodynamic field theory (TFT). The aim of this work was to determine the nonlinear flux-force relations that respect the thermodynamic theorems for systems far from equilibrium. We propose a formulation of the TFT where one of the basic restrictions, namely, the closed-form solution for the skew-symmetric piece of the transport coefficients, has been removed. In addition, the general covariance principle is replaced by the De Donder-Prigogine thermodynamic covariance principle (TCP). The introduction of TCP requires the application of an appropriate mathematical formalism, which is referred to as the entropy-covariant formalism. By geometrical arguments, we prove the validity of the Glansdorff-Prigogine universal criterion of evolution. A new set of closure equations determining the nonlinear corrections to the linear ("Onsager") transport coefficients is also derived. The geometry of the thermodynamic space is non-Riemannian. However, it tends to be Riemannian for high values of the entropy production. In this limit, we recover the transport equations found by the old theory. Applications of our approach to transport in magnetically confined plasmas, materials submitted to temperature, and electric potential gradients or to unimolecular triangular chemical reactions can be found at references cited herein. Transport processes in tokamak plasmas are of particular interest. In this case, even in the absence of turbulence, the state of the plasma remains close to (but, it is not in) a state of local equilibrium. This prevents the transport relations from being linear.
Semiclassical theory for spatial density oscillations in fermionic systems.
Roccia, J; Brack, M; Koch, A
2010-01-01
We investigate the particle and kinetic-energy densities for a system of N fermions bound in a local (mean-field) potential V(r) . We generalize a recently developed semiclassical theory [J. Roccia and M. Brack, Phys. Rev. Lett. 100, 200408 (2008)] in which the densities are calculated in terms of the closed orbits of the corresponding classical system to D>1 dimensions. We regularize the semiclassical results (i) for the U(1) symmetry breaking occurring for spherical systems at r=0 and (ii) near the classical turning points where the Friedel oscillations are predominant and well reproduced by the shortest orbit going from r to the closest turning point and back. For systems with spherical symmetry, we show that there exist two types of oscillations which can be attributed to radial and nonradial orbits, respectively. The semiclassical theory is tested against exact quantum-mechanical calculations for a variety of model potentials. We find a very good overall numerical agreement between semiclassical and exact numerical densities even for moderate particle numbers N . Using a "local virial theorem," shown to be valid (except for a small region around the classical turning points) for arbitrary local potentials, we can prove that the Thomas-Fermi functional tau(TF)[rho] reproduces the oscillations in the quantum-mechanical densities to first order in the oscillating parts.
CHAOS THEORY, GLOBAL SYSTEMIC CHANGE, AND HYBRID WARS
A. Korybko
2016-01-01
Full Text Available The global system is being rocked by the dueling ambitions of two competing blocs, with the US and its allies fighting to reinforce their unipolar system while Russia and its partners struggle to forge a multipolar future. The rapidity and scope with which events are unfolding makes it overwhelming for the casual observer to make sense of all of the complex processes currently at play, and truth be told, it’s understandable that all of this can appear confusing. In an attempt to clarify the present state of global affairs and forecast the direction that it’s all headed in, the article begins by explaining the nature of chaos theory and describing how it’s applicable to conceptualizing contemporary international relations. Afterwards, the idea of “chaos sequencing” is proposed, which in essence is a model that can be used in understanding the process of chaotic change. Following that, the article addresses the topic of global systemic change and includes the most relevant examples for how this relates to the present day. Next, the research combines these two aforementioned elements (chaos theory and global systemic change and presents a forward-looking geopolitical analysis that incorporates cutting-edge Hybrid War theory and aims to put the New Cold War into its proper perspective. Finally, the article ends on a suggestive note in encouraging analysts to study the authors’ conceptualization of Hybrid War in order to better prepare themselves for understanding and responding to forthcoming international events.
Synthesis of Systemic Functional Theory & Dynamical Systems Theory for Socio-Cultural Modeling
2011-01-26
recurrence analysis, and clustering. These preliminary experiments were designed to determine both the identifying features of the texts and what...SFT is designed to account for how language is used, and it provides tools for the interpretation of (a) the underlying linguistic systems, (b) the... typography and graphology) (c) Context plane for register (field: what the text is about; tenor: the types of social relations; mode: spoken/written) and
Maximized Gust Loads of a Closed-Loop, Nonlinear Aeroelastic System Using Nonlinear Systems Theory
Silva, Walter A.
1999-01-01
The problem of computing the maximized gust load for a nonlinear, closed-loop aeroelastic aircraft is discusses. The Volterra theory of nonlinear systems is applied in order to define a linearized system that provides a bounds on the response of the nonlinear system of interest. The method is applied to a simplified model of an Airbus A310.
Weakly nonlinear simulation of planar stratified flows
King, Michael R. [Department of Chemical Engineering, University of Notre Dame, Notre Dame, Indiana 46556 (United States); McCready, Mark J. [Department of Chemical Engineering, University of Notre Dame, Notre Dame, Indiana 46556 (United States)
2000-01-01
The interfacial behavior of two-fluid, planar flows is studied by numerical integration of weakly-nonlinear amplitude equations derived via eigenfunction expansion of the governing equations. This study extends the range of classic Stuart-Landau theories by the inclusion of a spectrum of modes allowing all possible quadratic and cubic interactions. Results are obtained for four cases where linear and Stuart-Landau theories do not give a complete description; gas-liquid and oil-water pressure driven flow, matched-density liquid-liquid Couette flow, and the region of gas-liquid flow near resonance that switches from supercritical to subcritical. It is found that integration of amplitude equations gives better qualitative and quantitative agreement with experiments than Stuart-Landau theory. Further, the distinctively different behaviors of these systems can be understood in terms of the spectrum of nonlinear coefficients. In gas-liquid channel flow a low wave number wave is destabilized through quadratic interaction with the mean flow mode. For liquid-liquid Poiseuille flow, a low wave number wave is destabilized through cubic interactions with higher modes. For depth and viscosity ratios where liquid-liquid Couette flow is unstable to long waves and for which the growth rates are not too large, simulation results predict that the waves grow to a statistically steady state where there is no preferred wave number. Stabilization is provided by an apparently self-similar cascade of energy to higher modes that are linearly stable, explaining why no visible waves occur in experiments done in this region. While Stuart-Landau theory provides no prediction of wave amplitude above criticality for subcritical cases, simulations show that wave saturation at small amplitude is possible and suggests that subcritical predictions may not mean that steady waves do not exist. (c) 2000 American Institute of Physics.
Drainage in a model stratified porous medium
Datta, Sujit S; 10.1209/0295-5075/101/14002
2013-01-01
We show that when a non-wetting fluid drains a stratified porous medium at sufficiently small capillary numbers Ca, it flows only through the coarsest stratum of the medium; by contrast, above a threshold Ca, the non-wetting fluid is also forced laterally, into part of the adjacent, finer strata. The spatial extent of this partial invasion increases with Ca. We quantitatively understand this behavior by balancing the stratum-scale viscous pressure driving the flow with the capillary pressure required to invade individual pores. Because geological formations are frequently stratified, we anticipate that our results will be relevant to a number of important applications, including understanding oil migration, preventing groundwater contamination, and sub-surface CO$_{2}$ storage.
Stratified spin-up in a sliced, square cylinder
Munro, R. J. [Faculty of Engineering, University of Nottingham, Nottingham NG7 2RD (United Kingdom); Foster, M. R. [Department of Mathematical Sciences, Rensselaer Polytechnic Institute, Troy, New York 12180 (United States)
2014-02-15
We previously reported experimental and theoretical results on the linear spin-up of a linearly stratified, rotating fluid in a uniform-depth square cylinder [M. R. Foster and R. J. Munro, “The linear spin-up of a stratified, rotating fluid in a square cylinder,” J. Fluid Mech. 712, 7–40 (2012)]. Here we extend that analysis to a “sliced” square cylinder, which has a base-plane inclined at a shallow angle α. Asymptotic results are derived that show the spin-up phase is achieved by a combination of the Ekman-layer eruptions (from the perimeter region of the cylinder's lid and base) and cross-slope-propagating stratified Rossby waves. The final, steady state limit for this spin-up phase is identical to that found previously for the uniform depth cylinder, but is reached somewhat more rapidly on a time scale of order E{sup −1/2}Ω{sup −1}/log (α/E{sup 1/2}) (compared to E{sup −1/2}Ω{sup −1} for the uniform-depth cylinder), where Ω is the rotation rate and E the Ekman number. Experiments were performed for Burger numbers, S, between 0.4 and 16, and showed that for S≳O(1), the Rossby modes are severely damped, and it is only at small S, and during the early stages, that the presence of these wave modes was evident. These observations are supported by the theory, which shows the damping factors increase with S and are numerically large for S≳O(1)
Stably Stratified Flow in a Shallow Valley
Mahrt, L.
2017-01-01
Stratified nocturnal flow above and within a small valley of approximately 12-m depth and a few hundred metres width is examined as a case study, based on a network of 20 sonic anemometers and a central 20-m tower with eight levels of sonic anemometers. Several regimes of stratified flow over gentle topography are conceptually defined for organizing the data analysis and comparing with the existing literature. In our case study, a marginal cold pool forms within the shallow valley in the early evening but yields to larger ambient wind speeds after a few hours, corresponding to stratified terrain-following flow where the flow outside the valley descends to the valley floor. The terrain-following flow lasts about 10 h and then undergoes transition to an intermittent marginal cold pool towards the end of the night when the larger-scale flow collapses. During this 10-h period, the stratified terrain-following flow is characterized by a three-layer structure, consisting of a thin surface boundary layer of a few metres depth on the valley floor, a deeper boundary layer corresponding to the larger-scale flow, and an intermediate transition layer with significant wind-directional shear and possible advection of lee turbulence that is generated even for the gentle topography of our study. The flow in the valley is often modulated by oscillations with a typical period of 10 min. Cold events with smaller turbulent intensity and duration of tens of minutes move through the observational domain throughout the terrain-following period. One of these events is examined in detail.
Multi Dimensional CTL and Stratified Datalog
Theodore Andronikos
2010-02-01
Full Text Available In this work we define Multi Dimensional CTL (MD-CTL in short by extending CTL which is thedominant temporal specification language in practice. The need for Multi Dimensional CTL is mainlydue to the advent of semi-structured data. The common path nature of CTL and XPath which provides asuitable model for semi-structured data, has caused the emergence of work on specifying a relation amongthem aiming at exploiting the nice properties of CTL. Although the advantages of such an approach havealready been noticed [36, 26, 5], no formal definition of MD-CTL has been given. The goal of this workis twofold; a we define MD-CTL and prove that the “nice” properties of CTL (linear model checking andbounded model property transfer also to MD-CTL, b we establish new results on stratified Datalog. Inparticular, we define a fragment of stratified Datalog called Multi Branching Temporal (MBT in shortprograms that has the same expressive power as MD-CTL. We prove that by devising a linear translationbetween MBT and MD-CTL. We actually give the exact translation rules for both directions. We furtherbuild on this relation to prove that query evaluation is linear and checking satisfiability, containment andequivalence are EXPTIME–complete for MBT programs. The class MBT is the largest fragment of stratifiedDatalog for which such results exist in the literature.
Thermal mixing in a stratified environment
Kraemer, Damian; Cotel, Aline
1999-11-01
Laboratory experiments of a thermal impinging on a stratified interface have been performed. The thermal was released from a cylindrical reservoir located at the bottom of a Lucite tank. The stratified interface was created by filling the tank with two different saline solutions. The density of the lower layer is greater than that of the upper layer and the thermal fluid, thereby creating a stable stratification. A pH indicator, phenolphthalein, is used to visualize and quantify the amount of mixing produced by the impingement of the thermal at the interface. The upper layer contains a mixture of water, salt and sodium hydroxide. The thermal fluid is composed of water, sulfuric acid and phenolphthalein. When the thermal entrains and mixes fluid from the upper layer, a chemical reaction takes place, and the resulting mixed fluid is now visible. The ratio of base to acid, called the equivalence ratio, was varied throughout the experiments, as well as the Richardson number. The Richardson number is the ratio of potential to kinetic energy, and is based on the thermal quantities at the interface. Results indicate that the amount of mixing produced is proportional to the Richardson number raised to the -3/2 power. Previous experiments (Zhang and Cotel 1999) revealed that the entrainment rate of a thermal in a stratified environment follows the same power law.
General Systems Theory: Application To The Design Of Speech Communication Courses
Tucker, Raymond K.
1971-01-01
General systems theory can be applied to problems in the teaching of speech communication courses. The author describes general systems theory as it is applied to the designing, conducting and evaluation of speech communication courses. (Author/MS)
Affordances in activity theory and cognitive systems engineering
Albrechtsen, H.; Andersen, H.H.K.; Bødker, S.;
2001-01-01
is supplemented by careful analyses of other human modalities and activities than visual perception. Within HMI two well established perspectives on HMI,Activity Theory (AT) and Cognitive Systems Engineering (CSE), have discussed such analyses and design of action possibilities focusing on providing computer...... in HMI, notably those that have been putforward by Norman and Gaver, affordances are in the foreground, whereas the system or work area is in the background. AT and CSE share the view that the actors' perception of foreground and background shifts dynamically according to the actors'situational context...... in purposeful activity. AT and CSE follow the original notion by Gibson on the actor's dynamic shifting between foreground and background of the environment. Furthermore, their work- and actor-centred approach to analysis and designof information systems opens up to an extension of Gibson's original ideas...
Spatiotemporal Chaos in Distributed Systems: Theory and Practice
Pavlos, George P.; Iliopoulos, A. C.; Tsoutsouras, V. G.; Karakatsanis, L. P.; Pavlos, E. G.
This paper presents theoretical and experimental results concerning the hypothesis of spatiotemporal chaos in distributed physical systems far from equilibrium. Modern tools of nonlinear time series analysis, such as the correlation dimension and the maximum Lyapunov exponent, were applied to various time series, corresponding to different physical systems such as space plasmas (solar flares, magnetic-electric field components) lithosphere-faults system (earthquakes) brain and cardiac dynamics during or without epileptic episodes. Futhermore, the method of surrogate data was used for the exclusion of 'pseudo chaos' caused by the nonlinear distortion of a purely stochastic process. The results of the nonlinear analysis presented in this study constitute experimental evidence for significant phenomena indicated by the theory of nonequilibrium dynamics such as nonequilibrium phase transition, chaotic synchronization, chaotic intermittency, directed percolation, defect turbulence, spinodal nucleation and clustering.
Theory of generalized tautology in revised Kleene system
WU; Hongbo
2001-01-01
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Statistical mechanics of ecological systems: Neutral theory and beyond
Azaele, Sandro; Suweis, Samir; Grilli, Jacopo; Volkov, Igor; Banavar, Jayanth R.; Maritan, Amos
2016-07-01
The simplest theories often have much merit and many limitations, and, in this vein, the value of neutral theory (NT) of biodiversity has been the subject of much debate over the past 15 years. NT was proposed at the turn of the century by Stephen Hubbell to explain several patterns observed in the organization of ecosystems. Among ecologists, it had a polarizing effect: There were a few ecologists who were enthusiastic, and there were a larger number who firmly opposed it. Physicists and mathematicians, instead, welcomed the theory with excitement. Indeed, NT spawned several theoretical studies that attempted to explain empirical data and predicted trends of quantities that had not yet been studied. While there are a few reviews of NT oriented toward ecologists, the goal here is to review the quantitative aspects of NT and its extensions for physicists who are interested in learning what NT is, what its successes are, and what important problems remain unresolved. Furthermore, this review could also be of interest to theoretical ecologists because many potentially interesting results are buried in the vast NT literature. It is proposed to make these more accessible by extracting them and presenting them in a logical fashion. The focus of this review is broader than NT: new, more recent approaches for studying ecological systems and how one might introduce realistic non-neutral models are also discussed.
Weird astronomical theories of the solar system and beyond
Seargent, David
2016-01-01
After addressing strange cosmological hypotheses in Weird Universe, David Seargent tackles the no-less bizarre theories closer to home. Alternate views on the Solar System's formation, comet composition, and the evolution of life on Earth are only some of the topics he addresses in this new work. Although these ideas exist on the fringe of mainstream astronomy, they can still shed light on the origins of life and the evolution of the planets. Continuing the author's series of books popularizing strange astronomy facts and knowledge, Weird Astronomical Theories presents an approachable exploration of the still mysterious questions about the origin of comets, the pattern of mass extinctions on Earth, and more. The alternative theories discussed here do not come from untrained amateurs. The scientists whose work is covered includes the mid-20th century Russian S. K. Vsekhsvyatskii, cosmologist Max Tegmark, British astronomers Victor Clube and William Napier, and American Tom Van Flandern, a special...
Keldysh field theory for driven open quantum systems.
Sieberer, L M; Buchhold, M; Diehl, S
2016-09-01
Recent experimental developments in diverse areas-ranging from cold atomic gases to light-driven semiconductors to microcavity arrays-move systems into the focus which are located on the interface of quantum optics, many-body physics and statistical mechanics. They share in common that coherent and driven-dissipative quantum dynamics occur on an equal footing, creating genuine non-equilibrium scenarios without immediate counterpart in equilibrium condensed matter physics. This concerns both their non-thermal stationary states and their many-body time evolution. It is a challenge to theory to identify novel instances of universal emergent macroscopic phenomena, which are tied unambiguously and in an observable way to the microscopic drive conditions. In this review, we discuss some recent results in this direction. Moreover, we provide a systematic introduction to the open system Keldysh functional integral approach, which is the proper technical tool to accomplish a merger of quantum optics and many-body physics, and leverages the power of modern quantum field theory to driven open quantum systems.
Keldysh field theory for driven open quantum systems
Sieberer, L. M.; Buchhold, M.; Diehl, S.
2016-09-01
Recent experimental developments in diverse areas—ranging from cold atomic gases to light-driven semiconductors to microcavity arrays—move systems into the focus which are located on the interface of quantum optics, many-body physics and statistical mechanics. They share in common that coherent and driven-dissipative quantum dynamics occur on an equal footing, creating genuine non-equilibrium scenarios without immediate counterpart in equilibrium condensed matter physics. This concerns both their non-thermal stationary states and their many-body time evolution. It is a challenge to theory to identify novel instances of universal emergent macroscopic phenomena, which are tied unambiguously and in an observable way to the microscopic drive conditions. In this review, we discuss some recent results in this direction. Moreover, we provide a systematic introduction to the open system Keldysh functional integral approach, which is the proper technical tool to accomplish a merger of quantum optics and many-body physics, and leverages the power of modern quantum field theory to driven open quantum systems.
Application of Density Functional Theory to Systems Containing Metal Atoms
Bauschlicher, Charles W., Jr.
2006-01-01
The accuracy of density functional theory (DFT) for problems involving metal atoms is considered. The DFT results are compared with experiment as well as results obtained using the coupled cluster approach. The comparisons include geometries, frequencies, and bond energies. The systems considered include MO2, M(OH)+n, MNO+, and MCO+2. The DFT works well for frequencies and geometries, even in case with symmetry breaking; however, some examples have been found where the symmetry breaking is quite severe and the DFT methods do not work well. The calculation of bond energies is more difficult and examples of successes as well as failures of DFT will be given.
Development theory and changes in the international system
José Antonio Alonso
2012-12-01
Full Text Available Development theory has undergone several changes over the last two decades. However, the international reality has changed more profoundly. The increased heterogeneity of the developing world, the diverse experience of economic success among some developing countries, the new geography of global poverty, the increased multipolarity of the international system and the wider spheres of international public assets are just some of these changes. Thus, it is necessary to think again about the development process and the strategies that are required to promote economic and social change. This article represents an attempt to contribute to that reflection.
Iterative Feedback Tuning in Fuzzy Control Systems. Theory and Applications
Stefan Preitl
2006-07-01
Full Text Available The paper deals with both theoretical and application aspects concerningIterative Feedback Tuning (IFT algorithms in the design of a class of fuzzy controlsystems employing Mamdani-type PI-fuzzy controllers. The presentation is focused on twodegree-of-freedom fuzzy control system structures resulting in one design method. Thestability analysis approach based on Popov’s hyperstability theory solves the convergenceproblems associated to IFT algorithms. The suggested design method is validated by realtimeexperimental results for a fuzzy controlled nonlinear DC drive-type laboratoryequipment.
[The theory of functional systems in medicine: methodological aspects].
Khrutskiĭ, K S
2009-01-01
P.K. Anokhin's theory of functional systems (TFS) is a unique scientific development extending an original field of biomedical research initiated in this country by I.M. Sechenov, I.P. Pavlov, and A.A. Ukhtomsky. Unique methodology of TFS is based on the integrated approach to the study of human vital activity including psychic and somatic processes. The main results of the studies in the framework of TFS methodology and prospects for its further development are reviewed with special reference to the key mechanisms of eitiopathogenesis of chronic non-infectious diseases.
International conference on dynamical systems and game theory
Peixoto, Mauricio Matos; Rand, David A J; Dynamics, Games and Science II
2011-01-01
"Dynamics, Games and Science I and II" are a selection of surveys and research articles written by leading researchers in mathematics and its applications to the sciences. The majority of the contributions are on dynamical systems and game theory, focusing either on some of their most fundamental and theoretical developments or on their applications to modeling in biology, economics, engineering, finances and psychology. The aim of these books is to present cutting-edge research in these areas that can encourage graduate students and researchers in mathematics to develop them further
An eddy tracking algorithm based on dynamical systems theory
Conti, Daniel; Orfila, Alejandro; Mason, Evan; Sayol, Juan Manuel; Simarro, Gonzalo; Balle, Salvador
2016-11-01
This work introduces a new method for ocean eddy detection that applies concepts from stationary dynamical systems theory. The method is composed of three steps: first, the centers of eddies are obtained from fixed points and their linear stability analysis; second, the size of the eddies is estimated from the vorticity between the eddy center and its neighboring fixed points, and, third, a tracking algorithm connects the different time frames. The tracking algorithm has been designed to avoid mismatching connections between eddies at different frames. Eddies are detected for the period between 1992 and 2012 using geostrophic velocities derived from AVISO altimetry and a new database is provided for the global ocean.
Bioattractors: dynamical systems theory and the evolution of regulatory processes.
Jaeger, Johannes; Monk, Nick
2014-06-01
In this paper, we illustrate how dynamical systems theory can provide a unifying conceptual framework for evolution of biological regulatory systems. Our argument is that the genotype-phenotype map can be characterized by the phase portrait of the underlying regulatory process. The features of this portrait--such as attractors with associated basins and their bifurcations--define the regulatory and evolutionary potential of a system. We show how the geometric analysis of phase space connects Waddington's epigenetic landscape to recent computational approaches for the study of robustness and evolvability in network evolution. We discuss how the geometry of phase space determines the probability of possible phenotypic transitions. Finally, we demonstrate how the active, self-organizing role of the environment in phenotypic evolution can be understood in terms of dynamical systems concepts. This approach yields mechanistic explanations that go beyond insights based on the simulation of evolving regulatory networks alone. Its predictions can now be tested by studying specific, experimentally tractable regulatory systems using the tools of modern systems biology. A systematic exploration of such systems will enable us to understand better the nature and origin of the phenotypic variability, which provides the substrate for evolution by natural selection.
Embedding research in health systems: lessons from complexity theory.
Caffrey, Louise; Wolfe, Charles; McKevitt, Christopher
2016-07-22
Internationally, there has been increasing focus on creating health research systems. This article aims to investigate the challenges of implementing apparently simple strategies to support the development of a health research system. We focus on a case study of an English National Health Service Hospital Trust that sought to implement the national recommendation that health organisations should introduce a statement about research on all patient admission letters. We apply core concepts from complexity theory to the case study and undertake a documentary analysis of the email dialogue between staff involved in implementing this initiative. The process of implementing a research statement in patient admission letters in one clinical service took 1 year and 21 days. The length of time needed was influenced firstly by adaptive self-organisation, underpinned by competing interests. Secondly, it was influenced by the relationship between systems, rather than simply being a product of issues within those systems. The relationship between the health system and the research system was weaker than might have been expected. Responsibilities were unclear, leading to confusion and delayed action. Conventional ways of thinking about organisations suggest that change happens when leaders and managers change the strategic vision, structure or procedures in an organisation and then persuade others to rationally implement the strategy. However, health research systems are complex adaptive systems characterised by high levels of unpredictability due to self-organisation and systemic interactions, which give rise to 'emergent' properties. We argue for the need to study how micro-processes of organisational dynamics may give rise to macro patterns of behaviour and strategic organisational direction and for the use of systems approaches to investigate the emergent properties of health research systems.
Towards a Theory on the Design of Adaptive Transformation: A Systemic Approach
2010-05-21
theory requires exploring its differences with GST and chaos theory. In the 1960s, Ludwig von Bertalanffy elaborated GST as a new scientific discipline... Bertalanffy , General System Theory (New York: George Braziller, 1993), 37 (eleventh printing, 1968) 12 “Chaos and instability were not the same at...this field, indispensable references are: James Gleick, Chaos; Ludwig von Bertalanffy , General System Theory; Garnett Williams, Chaos Theory Tamed
Stratified shear flow in an inclined duct: coherent structures and mixing
Lefauve, Adrien; Partridge, Jamie; Dalziel, Stuart; Linden, Paul
2016-11-01
We present laboratory experiments on the exchange flow in an inclined square duct connecting two reservoirs at different densities. This system generates and maintains a stratified shear flow, which can be laminar, wavy or turbulent depending on the density difference and inclination angle. It is believed that the mean dissipation is set by the angle, and that high buoyancy Reynolds numbers (i.e. turbulent intensity) can be maintained, making this system suited for the study of continuously forced stratified turbulence. The talk will focus on the analysis of time-resolved, near-instantaneous 3D velocity and density data obtained by stereo particle image velocimetry (PIV) and laser induced fluorescence (LIF). This data allow for the visualisation of 3D coherent structures as well as turbulent mixing properties, which are key in understanding the dynamics of stratified turbulence. Supported by EPSRC Programme Grant EP/K034529/1 entitled "Mathematical Underpinnings of Stratified Turbulence".
What Learning Systems do Intelligent Agents Need? Complementary Learning Systems Theory Updated.
Kumaran, Dharshan; Hassabis, Demis; McClelland, James L
2016-07-01
We update complementary learning systems (CLS) theory, which holds that intelligent agents must possess two learning systems, instantiated in mammalians in neocortex and hippocampus. The first gradually acquires structured knowledge representations while the second quickly learns the specifics of individual experiences. We broaden the role of replay of hippocampal memories in the theory, noting that replay allows goal-dependent weighting of experience statistics. We also address recent challenges to the theory and extend it by showing that recurrent activation of hippocampal traces can support some forms of generalization and that neocortical learning can be rapid for information that is consistent with known structure. Finally, we note the relevance of the theory to the design of artificial intelligent agents, highlighting connections between neuroscience and machine learning.
System-reservoir theory with anharmonic baths: a perturbative approach
Bhadra, Chitrak; Banerjee, Dhruba
2016-04-01
In this paper we develop the formalism of a general system coupled to a reservoir (the words ‘bath’ and ‘reservoir’ will be used interchangeably) consisting of nonlinear oscillators, based on perturbation theory at the classical level, by extending the standard Zwanzig approach of elimination of bath degrees of freedom order by order in perturbation. We observe that the fluctuation dissipation relation (FDR) of the second kind in its standard form for harmonic baths gets modified due to the nonlinearity and this is manifested through higher powers of {{k}\\text{B}}T in the expression for two-time noise correlation. On the flip side, this very modification allows us to define a dressed (renormalized) system-bath coupling that depends on the temperature and the nonlinear parameters of the bath in such a way that the structure of the FDR (of the second kind) is maintained. As an aside, we also observe that the first moment of the noise arising from a nonlinear bath can be non-zero, even in the absence of any external drive, if the reservoir potential is asymmetric with respect to one of its minima, about which one builds up the perturbation theory.
Kinetic Theory of the Quantum Field Systems With Unstable Vacuum
Smolyansky, S A; Prozorkevich, A V
2003-01-01
The description of quantum field systems with meta-stable vacuum is motivated by studies of many physical problems (the decay of disoriented chiral condensate, the resonant decay of CP-odd meta-stable states, self-consistent model of QGP pre-equilibrium evolution, the phase transition problem in the systems with broken symmetry etc). A non-perturbative approach based on the kinetic description within the framework of the quasi-particle representation was proposed here. We restrict ourselves to scalar field theory with potentials of polynomial type. The back reaction mechanism, i.e. the particle production influence on background field is also discussed. Using the oscillator representation, we derive the generalized kinetic equation with non-pertrubative source term for description of particle-antiparticle creation under action of background field and equation of motion for it. As an illustrative example we consider one-component scalar theory with double-well potential. On this example, we study some features...
Time-dependent density-functional theory for extended systems
Botti, Silvana [European Theoretical Spectroscopy Facility (ETSF) (Country Unknown); Schindlmayr, Arno [European Theoretical Spectroscopy Facility (ETSF) (Country Unknown); Del Sole, Rodolfo [European Theoretical Spectroscopy Facility (ETSF) (Country Unknown); Reining, Lucia [European Theoretical Spectroscopy Facility (ETSF) (Country Unknown)
2007-03-15
For the calculation of neutral excitations, time-dependent density functional theory (TDDFT) is an exact reformulation of the many-body time-dependent Schroedinger equation, based on knowledge of the density instead of the many-body wavefunction. The density can be determined in an efficient scheme by solving one-particle non-interacting Schroedinger equations-the Kohn-Sham equations. The complication of the problem is hidden in the-unknown-time-dependent exchange and correlation potential that appears in the Kohn-Sham equations and for which it is essential to find good approximations. Many approximations have been suggested and tested for finite systems, where even the very simple adiabatic local-density approximation (ALDA) has often proved to be successful. In the case of solids, ALDA fails to reproduce optical absorption spectra, which are instead well described by solving the Bethe-Salpeter equation of many-body perturbation theory (MBPT). On the other hand, ALDA can lead to excellent results for loss functions (at vanishing and finite momentum transfer). In view of this and thanks to recent successful developments of improved linear-response kernels derived from MBPT, TDDFT is today considered a promising alternative to MBPT for the calculation of electronic spectra, even for solids. After reviewing the fundamentals of TDDFT within linear response, we discuss different approaches and a variety of applications to extended systems.
Face Recognition System Based on Spectral Graph Wavelet Theory
R. Premalatha Kanikannan
2014-09-01
Full Text Available This study presents an efficient approach for automatic face recognition based on Spectral Graph Wavelet Theory (SGWT. SGWT is analogous to wavelet transform and the transform functions are defined on the vertices of a weighted graph. The given face image is decomposed by SGWT at first. The energies of obtained sub-bands are fused together and considered as feature vector for the corresponding image. The performance of proposed system is analyzed on ORL face database using nearest neighbor classifier. The face images used in this study has variations in pose, expression and facial details. The results indicate that the proposed system based on SGWT is better than wavelet transform and 94% recognition accuracy is achieved.
Transition State Theory for dissipative systems without a dividing surface
Revuelta, F; Benito, R M; Borondo, F
2015-01-01
Transition State Theory is a central cornerstone in reaction dynamics. Its key step is the identification of a dividing surface that is crossed only once by all reactive trajectories. This assumption is often badly violated, especially when the reactive system is coupled to an environment. The calculations made in this way then overestimate the reaction rate and the results depend critically on the choice of the dividing surface. In this Letter, we study the phase space of a stochastically driven system close to an energetic barrier in order to identify the geometric structure unambiguously determining the reactive trajectories, which is then incorporated in a simple rate formula for reactions in condensed phase that is both independent of the dividing surface and exact.
Applicability of Dynamic Facilitation Theory to Binary Hard Disk Systems
Isobe, Masaharu; Keys, Aaron S.; Chandler, David; Garrahan, Juan P.
2016-09-01
We numerically investigate the applicability of dynamic facilitation (DF) theory for glass-forming binary hard disk systems where supercompression is controlled by pressure. By using novel efficient algorithms for hard disks, we are able to generate equilibrium supercompressed states in an additive nonequimolar binary mixture, where microcrystallization and size segregation do not emerge at high average packing fractions. Above an onset pressure where collective heterogeneous relaxation sets in, we find that relaxation times are well described by a "parabolic law" with pressure. We identify excitations, or soft spots, that give rise to structural relaxation and find that they are spatially localized, their average concentration decays exponentially with pressure, and their associated energy scale is logarithmic in the excitation size. These observations are consistent with the predictions of DF generalized to systems controlled by pressure rather than temperature.
A General Systems Theory for Rain Formation in Warm Clouds
Selvam, A M
2012-01-01
A cumulus cloud model which can explain the observed characteristics of warm rain formation in monsoon clouds is presented. The model is based on classical statistical physical concepts and satisfies the principle of maximum entropy production. Atmospheric flows exhibit selfsimilar fractal fluctuations that are ubiquitous to all dynamical systems in nature, such as physical, chemical, social, etc and are characterized by inverse power law form for power (eddy energy) spectrum signifying long-range space-time correlations. A general systems theory model for atmospheric flows developed by the author is based on the concept that the large eddy energy is the integrated mean of enclosed turbulent (small scale) eddies. This model gives scale-free universal governing equations for cloud growth processes. The model predicted cloud parameters are in agreement with reported observations, in particular, the cloud dropsize distribution. Rain formation can occur in warm clouds within 30minutes lifetime under favourable co...
HRM Model in Tourism, Based on Dialectical Systems Theory
Simona Šarotar Žižek
2015-12-01
Full Text Available A human resources management (HRM model integrating trends in HRM with trends in tourism into a dialectical system by the Dialectical Systems Theory (DST. HRM strategy, integrated within the tourism organization’s (to’s strategy is implemented through functional strategies helping their users to achieve a requisitely holistic (rh HRM strategy replacing the prevailing one-sided ones. to’s strategy covers: employees (1 planning, (2 acquisition and selection, (3 development and training, (4 diversity management, (5 teamwork and creativity, (6 motivation and rewarding, (7 stress reduction and health, (8 relationships, (9 personal holism, (10 well-being, (11 work and results assessment; etc. Everyone matters; their synergy is crucial. An innovated HRM model for TOS, which applies employees’, organizations’ rh and integrates new knowledge about HRM. HRM belongs to central managers’ tools. Their HRM must be adapted for TOS, where employees are crucial.
Extending Molecular Theory to Steady-State Diffusing Systems
FRINK,LAURA J. D.; SALINGER,ANDREW G.; THOMPSON,AIDAN P.
1999-10-22
Predicting the properties of nonequilibrium systems from molecular simulations is a growing area of interest. One important class of problems involves steady state diffusion. To study these cases, a grand canonical molecular dynamics approach has been developed by Heffelfinger and van Swol [J. Chem. Phys., 101, 5274 (1994)]. With this method, the flux of particles, the chemical potential gradients, and density gradients can all be measured in the simulation. In this paper, we present a complementary approach that couples a nonlocal density functional theory (DFT) with a transport equation describing steady-state flux of the particles. We compare transport-DFT predictions to GCMD results for a variety of ideal (color diffusion), and nonideal (uphill diffusion and convective transport) systems. In all cases excellent agreement between transport-DFT and GCMD calculations is obtained with diffusion coefficients that are invariant with respect to density and external fields.
Applications of self-consistent field theory in polymer systems
YANG; Yuliang; QIU; Feng; TANG; Ping; ZHANG; Hongdong
2006-01-01
The self-consistent field theory (SCFT) based upon coarse-grained model is especially suitable for investigating thermodynamic equilibrium morphology and the phase diagram of inhomogeneous polymer systems subjected to phase separation. The advantage of this model is that the details of the chain such as the architecture of the chain and the sequence of blocks can be considered. We present here an overview of SCFT approach and its applications in polymeric systems. In particular, we wish to focus on our group's achievements in applications of SCFT in such fields: simulation of microphase separation morphologies of multiblock copolymers with a complex molecular architecture, interactions between brush-coated sheets in a polymer matrix, mixtures of flexible polymers and small molecular liquid crystals at the interface, shapes of polymer-chain-anchored fluid vesicles, self-assembled morphologies of block copolymers in dilute solution, and so on. Finally, the further developments as well as the perspective applications of SCFT are discussed.
Parabasal theory for plane-symmetric systems including freeform surfaces
Abd El-Maksoud, Rania H.; Hillenbrand, Matthias; Sinzinger, Stefan
2014-03-01
An extension of paraxial theory to systems with a single plane of symmetry is provided. This parabasal model is based on the evaluation of a differential region around the reference ray that is defined by the center of the object and the center of the stop. To include freeform surfaces in this model, the local curvatures at the intersection point of the reference ray and the surface are evaluated. As an application, a generalized Scheimpflug principle is presented. The validity of the derived formulas is tested for highly tilted surfaces and is in good agreement with the exact ray tracing results. The analytical expressions are used to provide a first-order layout design of a planar imaging system.
Complex adaptive systems and game theory: An unlikely union
Hadzikadic, M.; Carmichael, T.; Curtin, C.
2010-01-01
A Complex Adaptive System is a collection of autonomous, heterogeneous agents, whose behavior is defined with a limited number of rules. A Game Theory is a mathematical construct that assumes a small number of rational players who have a limited number of actions or strategies available to them. The CAS method has the potential to alleviate some of the shortcomings of GT. On the other hand, CAS researchers are always looking for a realistic way to define interactions among agents. GT offers an attractive option for defining the rules of such interactions in a way that is both potentially consistent with observed real-world behavior and subject to mathematical interpretation. This article reports on the results of an effort to build a CAS system that utilizes GT for determining the actions of individual agents. ?? 2009 Wiley Periodicals, Inc. Complexity, 16,24-42, 2010.
Application of queuing theory in inventory systems with substitution flexibility
Seyedhoseini, S. M.; Rashid, Reza; Kamalpour, Iman; Zangeneh, Erfan
2015-01-01
Considering the competition in today's business environment, tactical planning of a supply chain becomes more complex than before. In many multi-product inventory systems, substitution flexibility can improve profits. This paper aims to prepare a comprehensive substitution inventory model, where an inventory system with two substitute products with ignorable lead time has been considered, and effects of simultaneous ordering have been examined. In this paper, demands of customers for both of the products have been regarded as stochastic parameters, and queuing theory has been used to construct a mathematical model. The model has been coded by C++, and it has been analyzed due to a real example, where the results indicate efficiency of proposed model.
Nodal aberration theory for wild-filed asymmetric optical systems
Chen, Yang; Cheng, Xuemin; Hao, Qun
2016-10-01
Nodal Aberration Theory (NAT) was used to calculate the zero field position in Full Field Display (FFD) for the given aberration term. Aiming at wide-filed non-rotational symmetric decentered optical systems, we have presented the nodal geography behavior of the family of third-order and fifth-order aberrations. Meanwhile, we have calculated the wavefront aberration expressions when one optical element in the system is tilted, which was not at the entrance pupil. By using a three-piece-cellphone lens example in optical design software CodeV, the nodal geography is testified under several situations; and the wavefront aberrations are calculated when the optical element is tilted. The properties of the nodal aberrations are analyzed by using Fringe Zernike coefficients, which are directly related with the wavefront aberration terms and usually obtained by real ray trace and wavefront surface fitting.
Developmental Systems of Students' Personal Theories about Education
Barger, Michael M.; Linnenbrink-Garcia, Lisa
2017-01-01
Children hold many personal theories about education: theories about themselves, knowledge, and the learning process. Personal theories help children predict what their actions will cause, and therefore relate to motivation, self-regulation, and achievement. Researchers typically examine how specific types of personal theories develop…
An enactive and dynamical systems theory account of dyadic relationships
Miriam eKyselo
2014-05-01
Full Text Available Many social relationships are a locus of struggle and suffering, either at the individual or interactional level. In this paper we explore why this is the case and suggest a modeling approach for dyadic interactions and the well-being of the participants. To this end we bring together an enactive approach to self with dynamical systems theory. Our basic assumption is that the quality of any social interaction or relationship fundamentally depends on the nature and constitution of the individuals engaged in these interactions. From an enactive perspective the self is conceived as an embodied and socially enacted autonomous system striving to maintain an identity. This striving is involves a basic two-fold goal: the ability to exist as an individual in its own right, while also being open to and affected by others. In terms of dynamical systems theory one can thus consider the individual self as a self-other organized system represented by a phase space spanned by the dimensions of distinction and participation, and in which attractors can be defined. Based on two everyday examples of dyadic relationship we propose a simple model of relationship dynamics in which struggle or well-being in the dyad is analyzed in terms of movements of dyadic states that are in tension or in harmony with individually developed attractors. Our model predicts that relationships can be sustained when the dyad develops a new joint attractor towards which dyadic states tend to move, and well-being when this attractor is in balance with the individuals’ attractors. We outline how this can inspire research on psychotherapy. The psychotherapy process itself provides a setting in which participants can become aware how they fare with regards to the two-fold norm of distinction and participation and develop, through active engagement between client (or couple and therapist, strategies to co-negotiate their self-organization.
Vanhoof, E.; Huysmans, P.; Aerts, Walter; Verelst, J.; Aveiro, D.; Tribolet, J.; Gouveia, D.
2014-01-01
This paper uses a mixed methods approach of design science and case study research to evaluate structures of Accounting Information Systems (AIS) that report in multiple Generally Accepted Accounting Principles (GAAP), using Normalized Systems Theory (NST). To comply with regulation, many companies
Toric Geometry and String Theory Descriptions of Qudit Systems
Belhaj, Adil; Sedra, Moulay Brahim
2014-01-01
In this paper, we propose a new way to approach qudit systems using toric geometry and related topics including the local mirror symmetry used in the string theory compactification. We refer to such systems as (n,d) quantum systems where $n$ and $d$ denote the number of the qudits and the basis states respectively. Concretely, we first relate the (n,d) quantum systems to the holomorphic sections of line bundles on n dimensional projective spaces CP^{n} with degree n(d-1). These sections are in one-to-one correspondence with d^n integral points on a n-dimensional simplex. Then, we explore the local mirror map in the toric geometry language to establish a linkage between the (n,d) quantum systems and type II D-branes placed at singularities of local Calabi-Yau manifolds. (1,d) and (2,d) are analyzed in some details and are found to be related to the mirror of the ALE space with the A_{d-1} singularity and a generalized conifold respectively.
The health information system security threat lifecycle: an informatics theory.
Fernando, Juanita I; Dawson, Linda L
2009-12-01
This manuscript describes the health information system security threat lifecycle (HISSTL) theory. The theory is grounded in case study data analyzing clinicians' health information system (HIS) privacy and security (P&S) experiences in the practice context. The 'questerview' technique was applied to this study of 26 clinicians situated in 3 large Australian (across Victoria) teaching hospitals. Questerviews rely on data collection that apply standardized questions and questionnaires during recorded interviews. Analysis (using Nvivo) involved the iterative scrutiny of interview transcripts to identify emergent themes. Issues including poor training, ambiguous legal frameworks containing punitive threats, productivity challenges, usability errors and the limitations of the natural hospital environment emerged from empirical data about the clinicians' HIS P&S practices. The natural hospital environment is defined by the permanence of electronic HISs (e-HISs), shared workspaces, outdated HIT infrastructure, constant interruption, a P&S regulatory environment that is not conducive to optimal training outcomes and budgetary constraints. The evidence also indicated the obtrusiveness, timeliness, and reliability of P&S implementations for clinical work affected participant attitudes to, and use of, e-HISs. The HISSTL emerged from the analysis of study evidence. The theory embodies elements such as the fiscal, regulatory and natural hospital environments which impede P&S implementations in practice settings. These elements conflict with improved patient care outcomes. Efforts by clinicians to avoid conflict and emphasize patient care above P&S tended to manifest as security breaches. These breaches entrench factors beyond clinician control and perpetuate those within clinician control. Security breaches of health information can progress through the HISSTL. Some preliminary suggestions for addressing these issues are proposed. Legislative frameworks that are not related to
Inverse scattering of dispersive stratified structures
Skaar, Johannes
2012-01-01
We consider the inverse scattering problem of retrieving the structural parameters of a stratified medium consisting of dispersive materials, given knowledge of the complex reflection coefficient in a finite frequency range. It is shown that the inverse scattering problem does not have a unique solution in general. When the dispersion is sufficiently small, such that the time-domain Fresnel reflections have durations less than the round-trip time in the layers, the solution is unique and can be found by layer peeling. Numerical examples with dispersive and lossy media are given, demonstrating the usefulness of the method for e.g. THz technology.
Topological Structures in Rotating Stratified Flows
Redondo, J. M.; Carrillo, A.; Perez, E.
2003-04-01
Detailled 2D Particle traking and PIV visualizations performed on a series of large scale laboratory experiments at the Coriolis Platform of the SINTEF in Trondheim have revealed several resonances which scale on the Strouhal, the Rossby and the Richardson numbers. More than 100 experiments spanned a wide range of Rossby Deformation Radii and the topological structures (Parabolic /Eliptic /Hyperbolic) of the quasi-balanced stratified-rotating flows were studied when stirring (akin to coastal mixing) occured at a side of the tank. The strong asymetry favored by the total vorticity produces a wealth of mixing patterns.
Dynamic information theory and information description of dynamic systems
无
2010-01-01
In this paper, we develop dynamic statistical information theory established by the author. Starting from the ideas that the state variable evolution equations of stochastic dynamic systems, classical and quantum nonequilibrium statistical physical systems and special electromagnetic field systems can be regarded as their information symbol evolution equations and the definitions of dynamic information and dynamic entropy, we derive the evolution equations of dynamic information and dynamic entropy that describe the evolution laws of dynamic information. These four kinds of evolution equations are of the same mathematical type. They show in unison when information transmits in coordinate space outside the systems that the time rate of change of dynamic information densities originates from their drift, diffusion and dissipation in state variable space inside the systems and coordinate space in the transmission processes, and that the time rate of change of dynamic entropy densities is caused by their drift, diffusion and production in state variable space inside the systems and coordinate space in the transmission processes. When space noise can be neglected, an information wave will appear. If we only consider the information change inside the systems, dynamic information evolution equations reduce to information equations corresponding to the dynamic equations which describe evolution laws of the above dynamic systems. This reveals that the evolution laws of respective dynamic systems can be described by information equations in a unified fashion. Hence, the evolution processes of these dynamic systems can be abstracted as the evolution processes of information. Furthermore, we present the formulas for information flow, information dissipation rate, and entropy production rate. We prove that the information production probably emerges in a dynamic system with internal attractive interaction between the elements, and derive a formula for this information
INSTRUCTIONAL SYSTEMS DESIGN (ISD: Theory and Practice in Second Life
Nil GOKSEL CANBEK
2011-08-01
Full Text Available The considerable changes in distance learning related technologies and Web 2.0 tools direct new immersive platforms to serve on the concept of avatar-driven interactions. In this sense, the immersive learning platforms, like Second Life (SL, embrace innovative forms of network based settings for effective community interactions. SL, as an interactive learning milieu, conducts 3D interactions and active education within the context of Instructional Systems Design (ISD which makes learning experiences efficient for both the tutor and learners on the platform designed on social networking. The platform gives an appropriate service to its users to be part of an instructional application of virtual worlds in where learners become connected though online activities. Within the learning theories existing nowadays, instructional designers, who are working in 3D environment like SL, are using mainly cognitive theory and constructivist strategy of learning. According to cognitive learning theory, people learn in different ways that are individually contextual and new trends in Instructional Design (ID had to address these differences. There are number of already approbated instructional models, which are used widely in the process of creation learning courses for 3D environments. The most frequently used model is ADDIE (Assess–Design–Develop–Implement– Evaluate, and the model PIE (Plan-Integrate–Evaluate, that is relatively new and become increasingly popular as it allows easy integration of technology in the classroom-oriented (virtual or real teaching. Based on the above mentioned concerns, this paper will examine the instructional design models used to create immersive courses within SL. Further, the paper will collect ideas on the instructional tools and technologies used for designing SL courses as these new technologies used in this environment draws heavily on andragogy. The paper will also clarify the obstacles on virtual learning
Lacy, Mark E.
1986-01-01
Provides general background on basic concepts of systems theory. Discusses applications of systems theory to computational and inferential chemistry in molecular and reaction systems, systems analysis, and synthesis. Describes methodology for studying chemical systems by computer and gives advantages of an integrated computational environment. (JM)
A non-extensive thermodynamic theory of ecological systems
Van Xuan, Le; Khac Ngoc, Nguyen; Lan, Nguyen Tri; Viet, Nguyen Ai
2017-06-01
After almost 30 years of development, it is not controversial issue that the so-called Tsallis entropy provides a useful approach to studying the complexity where the non-additivity of the systems under consideration is frequently met. Also, in the ecological research, Tsallis entropy, or in other words, q-entropy has been found itself as a generalized approach to define a range of diversity indices including Shannon-Wiener and Simpson indices. As a further stage of development in theoretical research, a thermodynamic theory based on Tsallis entropy or diversity indices in ecology has to be constructed for ecological systems to provide knowledge of ecological macroscopic behaviors. The standard method of theoretical physics is used in the manipulation and the equivalence between phenomenological thermodynamics and ecological aspects is the purpose of the ongoing research. The present work is in the line of the authors research to implement Tsallis non-extensivity approach to obtain the most important thermodynamic quantities of ecological systems such as internal energy Uq and temperature Tq based on a given modeled truncated Boltzmann distribution of the Whittaker plot for a dataset. These quantities have their own ecological meaning, especially the temperature Tq provides the insight of equilibrium condition among ecological systems as it is well-known in 0th law of thermodynamics.
Stochastic bifurcation in a driven laser system: experiment and theory.
Billings, Lora; Schwartz, Ira B; Morgan, David S; Bollt, Erik M; Meucci, Riccardo; Allaria, Enrico
2004-08-01
We analyze the effects of stochastic perturbations in a physical example occurring as a higher-dimensional dynamical system. The physical model is that of a class- B laser, which is perturbed stochastically with finite noise. The effect of the noise perturbations on the dynamics is shown to change the qualitative nature of the dynamics experimentally from a stochastic periodic attractor to one of chaoslike behavior, or noise-induced chaos. To analyze the qualitative change, we apply the technique of the stochastic Frobenius-Perron operator [L. Billings et al., Phys. Rev. Lett. 88, 234101 (2002)] to a model of the experimental system. Our main result is the identification of a global mechanism to induce chaoslike behavior by adding stochastic perturbations in a realistic model system of an optics experiment. In quantifying the stochastic bifurcation, we have computed a transition matrix describing the probability of transport from one region of phase space to another, which approximates the stochastic Frobenius-Perron operator. This mechanism depends on both the standard deviation of the noise and the global topology of the system. Our result pinpoints regions of stochastic transport whereby topological deterministic dynamics subjected to sufficient noise results in noise-induced chaos in both theory and experiment.
Theory for the Emergence of Modularity in Complex Systems
Deem, Michael; Park, Jeong-Man
2013-03-01
Biological systems are modular, and this modularity evolves over time and in different environments. A number of observations have been made of increased modularity in biological systems under increased environmental pressure. We here develop a theory for the dynamics of modularity in these systems. We find a principle of least action for the evolved modularity at long times. In addition, we find a fluctuation dissipation relation for the rate of change of modularity at short times. We discuss a number of biological and social systems that can be understood with this framework. The modularity of the protein-protein interaction network increases when yeast are exposed to heat shock, and the modularity of the protein-protein networks in both yeast and E. coli appears to have increased over evolutionary time. Food webs in low-energy, stressful environments are more modular than those in plentiful environments, arid ecologies are more modular during droughts, and foraging of sea otters is more modular when food is limiting. The modularity of social networks changes over time: stock brokers instant messaging networks are more modular under stressful market conditions, criminal networks are more modular under increased police pressure, and world trade network modularity has decreased
The application of information theory to biochemical signaling systems
Rhee, Alex; Cheong, Raymond; Levchenko, Andre
2012-01-01
Cell signaling can be thought of fundamentally as an information transmission problem in which chemical messengers relay information about the external environment to the decision centers within a cell. Due to the biochemical nature of cellular signal transduction networks, molecular noise will inevitably limit the fidelity of any messages received and processed by a cell’s signal transduction networks, leaving it with an imperfect impression of its environment. Fortunately, Shannon’s information theory provides a mathematical framework independent of network complexity that can quantify the amount of information that can be transmitted despite biochemical noise. In particular, the channel capacity can be used to measure the maximum number of stimuli a cell can distinguish based upon the noisy responses of its signaling systems. Here, we provide a primer for quantitative biologists that covers fundamental concepts of information theory, highlights several key considerations when experimentally measuring channel capacity, and describes successful examples of the application of information theoretic analysis to biological signaling. PMID:22872091
Study of soil-solid adhesion by grey system theory
ZHANG Li; REN Luquan; TONG Jin; SHI Yaowu
2004-01-01
The adhesion of soil to solid surface is a complicated interfacial reaction that relates to many factors. Quantitative descriptions of the forming procedures and the conditions of the adhesion interface forming can provide a guidance to the design of the soil-engaging component surfaces with a good anti-adhesion performance. Using a self-developed soil adhesion measurement device, the mean area and mean thickness of the adhesion interface waterfilm and the interfacial adhesion force varied with soil water content and vertical loads are measured. According to the gray system theory, the differential equations of the mean area and the mean thickness of waterfilm and the adhesion force of the interface are developed. The consequences between or among the factors related to the adhesion interface forming process are analyzed quantitatively with the gray correlation analyzing theory. The forming procedure of the adhesion interface and the influence on the mechanic behaviour of soil adhering on a solid surface are demonstrated by the experiments. The analysis will be beneficial to designing of soil-engaging component surfaces of terrain-machines.
World System Theory as an Integrator of the Social Science Curriculum.
Kutsche, Paul
1989-01-01
Defines and compares world system theory and dependency theory. Explains the advantages to anthropology, its students, and students from other disciplines. Defends the teaching of world system theory as an interdisciplinary course. Discusses problems with and reactions of faculty in other social sciences. (JS)
The field-circuit theory for direct-radiator loudspeaker system
SHEN Yong; SHEN Xiaoxiang; SHA Jiazheng
2003-01-01
In the conventional analogous circuit theory of the loudspeaker system, the vibrat-ing air in box is considered as lumped parameter; in this paper we consider the air as distributedparameter. The sound field theory and the analogous circuit theory are combined to analyze thecharacteristics of the loudspeaker system such as radiation acoustic power, frequency responseand impedance response.
Theory and application of stability for stochastic reaction diffusion systems
LUO Qi; DENG FeiQi; MAO XueRong; BAO JunDong; ZHANG YuTian
2008-01-01
So far, the Lyapunov direct method is still the moat effective technique in the study of stability for ordinary differential equations and stochastic differential equations. Due to the shortage of the corresponding Ito formula, this useful method has not been popularized in stochastic partial differential equations. The aim of this work is to try to extend the Lyapunov direct method to the Ito stochastic reaction diffusion systems and to establish the corresponding Lyapunov stability theory, including stability in probablity, asymptotic stability in probablity, end exponential stability in mean square. As the application of the obtained theorems, this paper addresses the stability of the Hopfield neural network and points out that the main results ob-tained by Holden Helge and Liao Xiaoxin et al. can be all regarded as the corollaries of the theorems presented in this paper.
Application of Grey System Theory in Design For Cost (DFC)
CHEN Xiao-chuan; FANG Ming-lun
2003-01-01
Design For Cost (DFC) is a branch of Design For X (DFX). In this paper, we defined DFC as a design method that analyzed and evaluated the product's life cycle cost ( LCC ) , then modified the design to reduce the LCC. Nowadays it is a very difficult thing to obtain LCC data in China or in developing countries. Statistical methods can not be used because available LCC data are few. In order to solve this problem, we used grey system theory. Then relations of cost factors were analyzed in LCC using grey relevant methods, and a GM( 1,1 ) model between design parameters and LCC was established. Using this model, we can estimate and control LCC by changing design parameters at the beginning of the design stage.
Communication theory of quantum systems. Ph.D. Thesis, 1970
Yuen, H. P. H.
1971-01-01
Communication theory problems incorporating quantum effects for optical-frequency applications are discussed. Under suitable conditions, a unique quantum channel model corresponding to a given classical space-time varying linear random channel is established. A procedure is described by which a proper density-operator representation applicable to any receiver configuration can be constructed directly from the channel output field. Some examples illustrating the application of our methods to the development of optical quantum channel representations are given. Optimizations of communication system performance under different criteria are considered. In particular, certain necessary and sufficient conditions on the optimal detector in M-ary quantum signal detection are derived. Some examples are presented. Parameter estimation and channel capacity are discussed briefly.
A semiclassical theory of dissipative Henon-Heiles system
Bag, B C; Bag, Bidhan Chandra; Ray, Deb Shankar
1999-01-01
A semiclassical theory of dissipative Henon-Heiles system is proposed. Based on $\\hbar$-scaling of an equation for evolution of Wigner quasiprobability distribution function in presence of dissipation and thermal diffusion, we derive a semiclassical equation for quantum fluctuations, governed by the dissipation and the curvature of the classical potential. We show how the initial quantum noise gets amplified by classical chaotic diffusion which is expressible in terms of correlation of stochastic fluctuations of the curvature of the potential due to classical chaos and ultimately settles down to equilibrium under the influence of dissipation. We also establish that there exists a critical limit to the expansion of phase space. The limit is set by chaotic diffusion and dissipation. Our semiclassical analysis is corroborated by numerical simulation of quantum operator master equation.
Microscopic Theory of Multipole Ordering in f-Electron Systems
Takashi Hotta
2012-01-01
Full Text Available A microscopic framework to determine multipole ordering in f-electron systems is provided on the basis of the standard quantum field theory. For the construction of the framework, a seven-orbital Hubbard Hamiltonian with strong spin-orbit coupling is adopted as a prototype model. A type of multipole and ordering vector is determined from the divergence of multipole susceptibility, which is evaluated in a random phase approximation. As an example of the application of the present framework, a multipole phase diagram on a three-dimensional simple cubic lattice is discussed for the case of n=2, where n denotes the average f-electron number per site. Finally, future problems concerning multipole ordering and fluctuations are briefly discussed.
Graph Theory and Qubit Information Systems of Extremal Black Branes
Belhaj, Adil; Segui, Antonio
2014-01-01
Using graph theory based on Adinkras, we consider once again the study of extremal black branes in the framework of quantum information. More precisely, we propose a one to one correspondence between qubit systems, Adinkras and certain extremal black branes obtained from type IIA superstring compactified on T^n. We accordingly interpret the real Hodge diagram of T^n as the geometry of a class of Adinkras formed by 2^n bosonic nodes representing n qubits. In this graphic representation, each node encodes information on the qubit quantum states and the charges of the extremal black branes built on T^n. The correspondence is generalized to n superqubits associated with odd and even geometries on the real supermanifold T^{n|n}. Using a combinatorial computation, general expressions describing the number of the bosonic and the fermionic states are obtained.
Statistical theory of the many-body nuclear system
De Pace, A
2002-01-01
A recently proposed statistical theory of the mean fields associated with the ground and excited collective states of a generic many-body system is extended by increasing the dimensions of the P-space. In applying the new framework to nuclear matter, in addition to the mean field energies we obtain their fluctuations as well, together with the ones of the wavefunctions, in first order of the expansion in the complexity of the Q-space states. The physics described by the latter is assumed to be random. To extract numerical predictions out of our scheme we develop a schematic version of the approach, which, while much simplified, yields results of significance on the size of the error affecting the mean fields, on the magnitude of the residual effective interaction, on the ground state spectroscopic factor and on the mixing occurring between the vectors spanning the P-space.
Microscopic theory on charge transports of a correlated multiorbital system
Arakawa, Naoya
2016-07-01
Current vertex correction (CVC), the backflowlike correction to the current, comes from conservation laws, and the CVC due to electron correlation contains information about many-body effects. However, it has been little understood how the CVC due to electron correlation affects the charge transports of a correlated multiorbital system. To improve this situation, I studied the in-plane resistivity ρa b and the Hall coefficient in the weak-field limit RH, in addition to the magnetic properties and the electronic structure, for a t2 g-orbital Hubbard model on a square lattice in a paramagnetic state away from or near an antiferromagnetic (AF) quantum-critical point (QCP) in the fluctuation-exchange (FLEX) approximation with the CVCs arising from the self-energy (Σ ), the Maki-Thompson (MT) irreducible four-point vertex function, and the main terms of the Aslamasov-Larkin (AL) one. Then, I found three main results about the CVCs. First, the main terms of the AL CVC do not qualitatively change the results obtained in the FLEX approximation with the Σ CVC and the MT CVC. Second, ρa b and RH near the AF QCP have a high-temperature region, governed mainly by the Σ CVC, and a low-temperature region, governed mainly by the Σ CVC and the MT CVC. Third, in case away from the AF QCP, the MT CVC leads to a considerable effect on only RH at low temperatures, although RH at high temperatures and ρa b at all temperatures considered are sufficiently described by including only the Σ CVC. Those findings reveal several aspects of many-body effects on the charge transports of a correlated multiorbital system. I also achieved the qualitative agreement with several experiments of Sr2RuO4 or Sr2Ru0.975Ti0.025O4 . Moreover, I showed several better points of this theory than other theories.
The Power and Promise of Developmental Systems Theory
Letitia Meynell
2008-09-01
Full Text Available I argue that it is time for many feminists to rethink their attitudes towards evolutionary biology, not because feminists have been wrong to be deeply sceptical about many of its claims, both explicit and implicit, but because biology itself has changed. A new appreciation for the importance of development in biology has become mainstream and a new ontology, associated with developmental systems theory (DST, has been introduced over the last two decades. This turn challenges some of the features of evolutionary biology that have most troubled feminists. DST undermines the idea of biologicales sence and challenges both nature /nurture and nature/culture distinctions. Freed from these conceptual constraints, evolutionary biology no longer poses the problems that have justified feminist scepticism. Indeed, feminists have already found useful applications for DST and I argue that they should expand their use of DST to support more radical and wide-ranging political theories.Si les féministes n’ont pas eu tort d’être profondément sceptiques face aux nombreuses revendications de la biologie, leur attitude face à cette science doit être remise en question car la biologie s’est transformée au courant des dernières décennies. La «théorie des systèmes de développement» (developmental systems theory-TDS est une théorie qui s’est considérablement développée et qui a pris beaucoup d’ampleur. Cette théorie n’accepte pas le concept d’essence biologique ce qui pose un défi important à la distinction nature/culture. Une des conséquences de cet apport théorique est que le scepticisme des féministes face à la biologie de l’évolution n’est plus justifié car la biologie ne comporte plus les contraintes essentialistes qui s’avéraient contentieuses. En effet, certaines féministes ont déjà trouvé des applications utiles pour la TDS et nous avançons que les féministes doivent maintenant élargir l’utilisation de la
Backes, Steffen
2017-04-15
The study of the electronic properties of correlated systems is a very diverse field and has lead to valuable insight into the physics of real materials. In these systems, the decisive factor that governs the physical properties is the ratio between the electronic kinetic energy, which promotes delocalization over the lattice, and the Coulomb interaction, which instead favours localized electronic states. Due to this competition, correlated electronic systems can show unique and interesting properties like the Metal-Insulator transition, diverse phase diagrams, strong temperature dependence and in general a high sensitivity to the environmental conditions. A theoretical description of these systems is not an easy task, since perturbative approaches that do not preserve the competition between the kinetic and interaction terms can only be applied in special limiting cases. One of the most famous approaches to obtain the electronic properties of a real material is the ab initio density functional theory (DFT) method. It allows one to obtain the ground state density of the system under investigation by mapping onto an effective non-interacting system that has to be found self-consistently. While being an exact theory, in practical implementations certain approximations have to be made to the exchange-correlation potential. The local density approximation (LDA), which approximates the exchange-correlation contribution to the total energy by that of a homogeneous electron gas with the corresponding density, has proven quite successful in many cases. Though, this approximation in general leads to an underestimation of electronic correlations and is not able to describe a metal-insulator transition due to electronic localization in the presence of strong Coulomb interaction. A different approach to the interacting electronic problem is the dynamical mean-field theory (DMFT), which is non-perturbative in the kinetic and interaction term but neglects all non
How complexity emerges in urban systems: Theory of urban morphology.
Goh, Segun; Choi, M Y; Lee, Keumsook; Kim, Kyung-Min
2016-05-01
Human beings develop the land and transform land use patterns, constructing artificial structures. Among them, the city is a representative system and its morphology has attracted much attention. While most existing studies have been devoted to individual dynamics and focused on the proximity of specific areas of a city, we here pay attention to the city as a complex system, where interactions between individuals give rise to emergent properties. Specifically, analyzing the big data on every building in Seoul City, we specify the relevant interactions among constituents and probe the emergence of complex land use patterns. In particular, based on the empirical observations, we illustrate that interactions between land uses are frustrated, which serves as a basic postulate of the theory of urban morphology. We examine this conjecture with the help of a layered Ising-type model and disclose that the actual land use pattern emerges at the criticality of the system in the presence of heterogeneously distributed fields. It is also remarked that our model, allowing quantitative predictions, can easily be applied to other cities around the world.
Cognitive performance modeling based on general systems performance theory.
Kondraske, George V
2010-01-01
General Systems Performance Theory (GSPT) was initially motivated by problems associated with quantifying different aspects of human performance. It has proved to be invaluable for measurement development and understanding quantitative relationships between human subsystem capacities and performance in complex tasks. It is now desired to bring focus to the application of GSPT to modeling of cognitive system performance. Previous studies involving two complex tasks (i.e., driving and performing laparoscopic surgery) and incorporating measures that are clearly related to cognitive performance (information processing speed and short-term memory capacity) were revisited. A GSPT-derived method of task analysis and performance prediction termed Nonlinear Causal Resource Analysis (NCRA) was employed to determine the demand on basic cognitive performance resources required to support different levels of complex task performance. This approach is presented as a means to determine a cognitive workload profile and the subsequent computation of a single number measure of cognitive workload (CW). Computation of CW may be a viable alternative to measuring it. Various possible "more basic" performance resources that contribute to cognitive system performance are discussed. It is concluded from this preliminary exploration that a GSPT-based approach can contribute to defining cognitive performance models that are useful for both individual subjects and specific groups (e.g., military pilots).
A criterion for the onset of slugging in horizontal stratified air-water countercurrent flow
Chun, Moon-Hyun; Lee, Byung-Ryung; Kim, Yang-Seok [Korea Advanced Institute of Science and Technology, Taejon (Korea, Republic of)] [and others
1995-09-01
This paper presents an experimental and theoretical investigation of wave height and transition criterion from wavy to slug flow in horizontal air-water countercurrent stratified flow conditions. A theoretical formula for the wave height in a stratified wavy flow regime has been developed using the concept of total energy balance over a wave crest to consider the shear stress acting on the interface of two fluids. From the limiting condition of the formula for the wave height, a necessary criterion for transition from a stratified wavy flow to a slug flow has been derived. A series of experiments have been conducted changing the non-dimensional water depth and the flow rates of air in a horizontal pipe and a duct. Comparisons between the measured data and the predictions of the present theory show that the agreement is within {plus_minus}8%.
Walloth, Christian
2016-01-01
This book presents a theory as well as methods to understand and to purposively influence complex systems. It suggests a theory of complex systems as nested systems, i. e. systems that enclose other systems and that are simultaneously enclosed by even other systems. According to the theory presented, each enclosing system emerges through time from the generative activities of the systems they enclose. Systems are nested and often emerge unplanned, and every system of high dynamics is enclosed by a system of slower dynamics. An understanding of systems with faster dynamics, which are always guided by systems of slower dynamics, opens up not only new ways to understanding systems, but also to effectively influence them. The aim and subject of this book is to lay out these thoughts and explain their relevance to the purposive development of complex systems, which are exemplified in case studies from an urban system. The interested reader, who is not required to be familiar with system-theoretical concepts or wit...
Network theory and its applications in economic systems
Huang, Xuqing
This dissertation covers the two major parts of my Ph.D. research: i) developing theoretical framework of complex networks; and ii) applying complex networks models to quantitatively analyze economics systems. In part I, we focus on developing theories of interdependent networks, which includes two chapters: 1) We develop a mathematical framework to study the percolation of interdependent networks under targeted-attack and find that when the highly connected nodes are protected and have lower probability to fail, in contrast to single scale-free (SF) networks where the percolation threshold pc = 0, coupled SF networks are significantly more vulnerable with pc significantly larger than zero. 2) We analytically demonstrates that clustering, which quantifies the propensity for two neighbors of the same vertex to also be neighbors of each other, significantly increases the vulnerability of the system. In part II, we apply the complex networks models to study economics systems, which also includes two chapters: 1) We study the US corporate governance network, in which nodes representing directors and links between two directors representing their service on common company boards, and propose a quantitative measure of information and influence transformation in the network. Thus we are able to identify the most influential directors in the network. 2) We propose a bipartite networks model to simulate the risk propagation process among commercial banks during financial crisis. With empirical bank's balance sheet data in 2007 as input to the model, we find that our model efficiently identifies a significant portion of the actual failed banks reported by Federal Deposit Insurance Corporation during the financial crisis between 2008 and 2011. The results suggest that complex networks model could be useful for systemic risk stress testing for financial systems. The model also identifies that commercial rather than residential real estate assets are major culprits for the
Lyapunov analysis: from dynamical systems theory to applications
Cencini, Massimo; Ginelli, Francesco
2013-06-01
[17], von Neumann [18], Krylov [19]3 and Asonov and Sinai [20] on ergodic theory. Lyapunov exponents quantify exponential sensitivity to initial conditions and provide direct access to the entropy production in ergodic systems via the Pesin theory [21]. Further advances have been made possible by the introduction of proper physical invariant measures for certain dissipative systems due to Sinai [22], Ruelle [23] and Bowen [24, 25]. However, it was necessary to wait until the end of the 1970s before the independent works of Shimada and Nagashima [26] and Benettin et al [27] introduced the numerical algorithms required to compute Lyapunov exponents beyond the largest one. The availability of such algorithms and also, at about the same time, of those necessary for the computation of fractal dimensions and entropies by Grassberger and Procaccia [28], made possible the study of chaotic behavior in physically relevant models. Lyapunov analysis, applied to experimental systems [29], was also made possible by a combination of these numerical methods with ideas from nonlinear time series analysis [30]. As a result, it is nowadays widely recognized that Lyapunov exponents are a central tool of chaos theory, crucial for characterizing a number of interesting physical properties including dynamical entropies and fractal dimensions [31]. Their pivotal role in modern dynamical systems theory has been established by a fruitful exchange between a rigorous (and beautiful) mathematical theory and the algorithmic approaches essential for understanding many physical phenomena. From the 1990s to the present, with the concomitant progress in both theoretical understanding and computer capabilities, there has been a progressive shift of interest from low dimensional towards high dimensional systems. This shift towards dynamics characterized by many degrees of freedom, possibly spatially organized and/or with several characteristic temporal scales, has been accompanied by the need for
Principles of General Systems Theory: Some Implications for Higher Education Administration
Gilliland, Martha W.; Gilliland, J. Richard
1978-01-01
Three principles of general systems theory are presented and systems theory is distinguished from systems analysis. The principles state that all systems tend to become more disorderly, that they must be diverse in order to be stable, and that only those maximizing their resource utilization for doing useful work will survive. (Author/LBH)
BOOK REVIEW: Theory of Neural Information Processing Systems
Galla, Tobias
2006-04-01
It is difficult not to be amazed by the ability of the human brain to process, to structure and to memorize information. Even by the toughest standards the behaviour of this network of about 1011 neurons qualifies as complex, and both the scientific community and the public take great interest in the growing field of neuroscience. The scientific endeavour to learn more about the function of the brain as an information processing system is here a truly interdisciplinary one, with important contributions from biology, computer science, physics, engineering and mathematics as the authors quite rightly point out in the introduction of their book. The role of the theoretical disciplines here is to provide mathematical models of information processing systems and the tools to study them. These models and tools are at the centre of the material covered in the book by Coolen, Kühn and Sollich. The book is divided into five parts, providing basic introductory material on neural network models as well as the details of advanced techniques to study them. A mathematical appendix complements the main text. The range of topics is extremely broad, still the presentation is concise and the book well arranged. To stress the breadth of the book let me just mention a few keywords here: the material ranges from the basics of perceptrons and recurrent network architectures to more advanced aspects such as Bayesian learning and support vector machines; Shannon's theory of information and the definition of entropy are discussed, and a chapter on Amari's information geometry is not missing either. Finally the statistical mechanics chapters cover Gardner theory and the replica analysis of the Hopfield model, not without being preceded by a brief introduction of the basic concepts of equilibrium statistical physics. The book also contains a part on effective theories of the macroscopic dynamics of neural networks. Many dynamical aspects of neural networks are usually hard to find in the
Coarse mesh transport theory model for heterogeneous systems
Ilas, Danut
To improve fuel utilization, recent reactor cores have become substantially more heterogeneous. In these cores, use of variable fuel enrichments and strong absorbers lead to high neutron flux gradients, which may limit the accuracy (validity) of diffusion theory based methods. In fact, the diffusion equation itself may become a poor approximation of the Boltzmann equation, the exact equation that describes the neutron flux. Therefore, numerical methods to solve the transport equation efficiently over a large heterogeneous region (such as a reactor core) are very desirable in case where the diffusion approximation breaks down. Presently, the only methods capable of computing the power (flux) distributions very accurately throughout a large system such as a nuclear reactor core are the Monte-Carlo or the fine-mesh transport theory methods. Both these methods suffer from the long computational time which makes them useless for routine core calculations. Starting from a variational principle that admits trial functions that can be discontinuous at coarse mesh (assembly) interfaces, we propose a method to solve the transport equation on a spatial grid made up of meshes as large as the size of a fuel assembly. The variational principle is derived for the most general case, but further methods are developed for one-dimensional geometry with the angular variable treated by discrete ordinates. The method uses the finite element approach for the space variable with basis functions precomputed for each element to obtain an algebraic linear system of equations. The eigenvalue of this system is the multiplication constant and the eigenvector represents the incoming angular fluxes for each coarse mesh. The latter allows the reconstruction of the fine mesh solution (angular flux) throughout the domain of interest when used with the basis functions (surface Green's function) for each coarse mesh. The method requires no homogenization procedure that can be a serious source of
Stratified growth in Pseudomonas aeruginosa biofilms
Werner, E.; Roe, F.; Bugnicourt, A.;
2004-01-01
In this study, stratified patterns of protein synthesis and growth were demonstrated in Pseudomonas aeruginosa biofilms. Spatial patterns of protein synthetic activity inside biofilms were characterized by the use of two green fluorescent protein (GFP) reporter gene constructs. One construct...... carried an isopropyl-beta-D-thiogalactopyranoside (IPTG)-inducible gfpmut2 gene encoding a stable GFP. The second construct carried a GFP derivative, gfp-AGA, encoding an unstable GFP under the control of the growth-rate-dependent rrnBp(1) promoter. Both GFP reporters indicated that active protein...... of oxygen limitation in the biofilm. Oxygen microelectrode measurements showed that oxygen only penetrated approximately 50 mum into the biofilm. P. aeruginosa was incapable of anaerobic growth in the medium used for this investigation. These results show that while mature P. aeruginosa biofilms contain...
Clustering of floating particles in stratified turbulence
Boffetta, Guido; de Lillo, Filippo; Musacchio, Stefano; Sozza, Alessandro
2016-11-01
We study the dynamics of small floating particles transported by stratified turbulence in presence of a mean linear density profile as a simple model for the confinement and the accumulation of plankton in the ocean. By means of extensive direct numerical simulations we investigate the statistical distribution of floaters as a function of the two dimensionless parameters of the problem. We find that vertical confinement of particles is mainly ruled by the degree of stratification, with a weak dependency on the particle properties. Conversely, small scale fractal clustering, typical of non-neutral particles in turbulence, depends on the particle relaxation time and is only weakly dependent on the flow stratification. The implications of our findings for the formation of thin phytoplankton layers are discussed.
Self-consistent theory for systems with mesoscopic fluctuations
Ciach, A.; Góźdź, W. T.
2016-10-01
We have developed a theory for inhomogeneous systems that allows for the incorporation of the effects of mesoscopic fluctuations. A hierarchy of equations relating the correlation and direct correlation functions for the local excess φ ≤ft(\\mathbf{r}\\right) of the volume fraction of particles ζ has been obtained, and an approximation leading to a closed set of equations for the two-point functions has been introduced for the disordered inhomogeneous phase. We have numerically solved the self-consistent equations for one-dimensional (1D) and three-dimensional (3D) models with short-range attraction and long-range repulsion. Predictions for all of the qualitative properties of the 1D model agree with the exact results, but only semi-quantitative agreement is obtained in the simplest version of the theory. The effects of fluctuations in the two 3D models considered are significantly different, despite the very similar properties of these models in the mean-field approximation. In both cases we obtain the sequence of large-small-large compressibility for increasing ζ. The very small compressibility is accompanied by the oscillatory decay of correlations with correlation lengths that are orders of magnitude larger than the size of particles. In one of the two models considered, the small compressibility becomes very small and the large compressibility becomes very large with decreasing temperature, and eventually van der Waals loops appear. Further studies are necessary in order to determine the nature of the strongly inhomogeneous phase present for intermediate volume fractions in 3D.
Chen, Huey T
2016-12-01
Theories of program and theories of evaluation form the foundation of program evaluation theories. Theories of program reflect assumptions on how to conceptualize an intervention program for evaluation purposes, while theories of evaluation reflect assumptions on how to design useful evaluation. These two types of theories are related, but often discussed separately. This paper attempts to use three theoretical perspectives (reductionism, systems thinking, and pragmatic synthesis) to interface them and discuss the implications for evaluation practice. Reductionism proposes that an intervention program can be broken into crucial components for rigorous analyses; systems thinking view an intervention program as dynamic and complex, requiring a holistic examination. In spite of their contributions, reductionism and systems thinking represent the extreme ends of a theoretical spectrum; many real-world programs, however, may fall in the middle. Pragmatic synthesis is being developed to serve these moderate- complexity programs. These three theoretical perspectives have their own strengths and challenges. Knowledge on these three perspectives and their evaluation implications can provide a better guide for designing fruitful evaluations, improving the quality of evaluation practice, informing potential areas for developing cutting-edge evaluation approaches, and contributing to advancing program evaluation toward a mature applied science.
Recent trends in social systems quantitative theories and quantitative models
Hošková-Mayerová, Šárka; Soitu, Daniela-Tatiana; Kacprzyk, Janusz
2017-01-01
The papers collected in this volume focus on new perspectives on individuals, society, and science, specifically in the field of socio-economic systems. The book is the result of a scientific collaboration among experts from “Alexandru Ioan Cuza” University of Iaşi (Romania), “G. d’Annunzio” University of Chieti-Pescara (Italy), "University of Defence" of Brno (Czech Republic), and "Pablo de Olavide" University of Sevilla (Spain). The heterogeneity of the contributions presented in this volume reflects the variety and complexity of social phenomena. The book is divided in four Sections as follows. The first Section deals with recent trends in social decisions. Specifically, it aims to understand which are the driving forces of social decisions. The second Section focuses on the social and public sphere. Indeed, it is oriented on recent developments in social systems and control. Trends in quantitative theories and models are described in Section 3, where many new formal, mathematical-statistical to...
System of marketing deciding support based on game theory
Gordana Dukić
2008-12-01
Full Text Available Quantitative methods and models can be applied in numerous spheres of marketing deciding. The choice of optimal strategy in product advertising is one of the problems that the marketing-management often meets. The use of models developed within the framework of game theory makes significantly easier to find out the solutions of conflict situations that appear herewith. The system of deciding support presented in this work is based on the supposition that two opposed sides take part in the game. With the aim of deciding process promotion, the starting model incorporates computer simulation of percentile changes in the market share that represent elements of payment matrix. The supposition is that the random variables that represent them follow the normal division. It is necessary to carry out the evaluation of their parameters because of relevant data. Information techniques, computer and the adequate program applications take the special position in solving and analysis of the suggested model. This kind of their application represents the basic characteristic of the deciding support system.
General systems theory, brain organization, and early experiences.
Denenberg, V H
1980-01-01
Three hypothetical brain processes--interhemispheric coupling, hemispheric activation, and interhemispheric inhibition--are derived from an equation characterizing general systems theory. To investigate these processes, experimental rats were reared under differing early experience conditions. When adult, they had their right or left neocortex lesioned, had a sham operation, or were left undisturbed. Interhemispheric coupling was measured by means of a correlation coefficient between the right and left hemispheres. The presence of a significant positive correlation is taken as evidence of a negative feedback loop between the hemispheres. In one experimental population, in which rats did not receive any extra stimulation in infancy, the correlation was not significantly different from zero, thus implying that the two hemispheres were operating independently. In another population, in which rats had received handling stimulation in infancy, the correlation coefficient was significant (0.543), indicating that the hemispheres were coupled in a systems arrangement. The processes of hemispheric activation and interhemispheric inhibition were assessed by comparing the mean performance of the two unilateral lesion groups and the group with intact brain. The two rat populations had different forms of brain organizations as measured by these processes. These analyses show that the behavior of the isolated hemisphere cannot be directly extrapolated to the behavior of the connected hemisphere. If there is hemispheric coupling via a negative feedback loop or if there is interhemispheric inhibition, then the disconnected hemisphere may show behaviors that are not evident in the normal connected condition.
A theory of nonequilibrium steady states in quantum chaotic systems
Wang, Pei
2017-09-01
Nonequilibrium steady state (NESS) is a quasistationary state, in which exist currents that continuously produce entropy, but the local observables are stationary everywhere. We propose a theory of NESS under the framework of quantum chaos. In an isolated quantum system whose density matrix follows a unitary evolution, there exist initial states for which the thermodynamic limit and the long-time limit are noncommutative. The density matrix \\hat ρ of these states displays a universal structure. Suppose that \\renewcommand{\\ket}[1]{{\\vert #1 >}} \\ketα and \\renewcommand{\\ket}[1]{{\\vert #1 >}} \\ketβ are different eigenstates of the Hamiltonian with energies E_α and E_β , respectively. \\renewcommand{\\bra}[1]{} \\braα\\hat ρ \\ketβ behaves as a random number which has zero mean. In thermodynamic limit, the variance of \\renewcommand{\\bra}[1]{} \\braα\\hat ρ \\ketβ is a smooth function of ≤ft\\vert E_α-E_β\\right\\vert , scaling as 1/≤ft\\vert E_α-E_β\\right\\vert 2 in the limit ≤ft\\vert E_α-E_β\\right\\vert \\to 0 . If and only if this scaling law is obeyed, the initial state evolves into NESS in the long time limit. We present numerical evidence of our hypothesis in a few chaotic models. Furthermore, we find that our hypothesis indicates the eigenstate thermalization hypothesis (ETH) for current operators in a bipartite system.
Switching theory-based steganographic system for JPEG images
Cherukuri, Ravindranath C.; Agaian, Sos S.
2007-04-01
Cellular communications constitute a significant portion of the global telecommunications market. Therefore, the need for secured communication over a mobile platform has increased exponentially. Steganography is an art of hiding critical data into an innocuous signal, which provide answers to the above needs. The JPEG is one of commonly used format for storing and transmitting images on the web. In addition, the pictures captured using mobile cameras are in mostly in JPEG format. In this article, we introduce a switching theory based steganographic system for JPEG images which is applicable for mobile and computer platforms. The proposed algorithm uses the fact that energy distribution among the quantized AC coefficients varies from block to block and coefficient to coefficient. Existing approaches are effective with a part of these coefficients but when employed over all the coefficients they show there ineffectiveness. Therefore, we propose an approach that works each set of AC coefficients with different frame work thus enhancing the performance of the approach. The proposed system offers a high capacity and embedding efficiency simultaneously withstanding to simple statistical attacks. In addition, the embedded information could be retrieved without prior knowledge of the cover image. Based on simulation results, the proposed method demonstrates an improved embedding capacity over existing algorithms while maintaining a high embedding efficiency and preserving the statistics of the JPEG image after hiding information.
Stratified sampling design based on data mining.
Kim, Yeonkook J; Oh, Yoonhwan; Park, Sunghoon; Cho, Sungzoon; Park, Hayoung
2013-09-01
To explore classification rules based on data mining methodologies which are to be used in defining strata in stratified sampling of healthcare providers with improved sampling efficiency. We performed k-means clustering to group providers with similar characteristics, then, constructed decision trees on cluster labels to generate stratification rules. We assessed the variance explained by the stratification proposed in this study and by conventional stratification to evaluate the performance of the sampling design. We constructed a study database from health insurance claims data and providers' profile data made available to this study by the Health Insurance Review and Assessment Service of South Korea, and population data from Statistics Korea. From our database, we used the data for single specialty clinics or hospitals in two specialties, general surgery and ophthalmology, for the year 2011 in this study. Data mining resulted in five strata in general surgery with two stratification variables, the number of inpatients per specialist and population density of provider location, and five strata in ophthalmology with two stratification variables, the number of inpatients per specialist and number of beds. The percentages of variance in annual changes in the productivity of specialists explained by the stratification in general surgery and ophthalmology were 22% and 8%, respectively, whereas conventional stratification by the type of provider location and number of beds explained 2% and 0.2% of variance, respectively. This study demonstrated that data mining methods can be used in designing efficient stratified sampling with variables readily available to the insurer and government; it offers an alternative to the existing stratification method that is widely used in healthcare provider surveys in South Korea.
Information content of household-stratified epidemics
T.M. Kinyanjui
2016-09-01
Full Text Available Household structure is a key driver of many infectious diseases, as well as a natural target for interventions such as vaccination programs. Many theoretical and conceptual advances on household-stratified epidemic models are relatively recent, but have successfully managed to increase the applicability of such models to practical problems. To be of maximum realism and hence benefit, they require parameterisation from epidemiological data, and while household-stratified final size data has been the traditional source, increasingly time-series infection data from households are becoming available. This paper is concerned with the design of studies aimed at collecting time-series epidemic data in order to maximize the amount of information available to calibrate household models. A design decision involves a trade-off between the number of households to enrol and the sampling frequency. Two commonly used epidemiological study designs are considered: cross-sectional, where different households are sampled at every time point, and cohort, where the same households are followed over the course of the study period. The search for an optimal design uses Bayesian computationally intensive methods to explore the joint parameter-design space combined with the Shannon entropy of the posteriors to estimate the amount of information in each design. For the cross-sectional design, the amount of information increases with the sampling intensity, i.e., the designs with the highest number of time points have the most information. On the other hand, the cohort design often exhibits a trade-off between the number of households sampled and the intensity of follow-up. Our results broadly support the choices made in existing epidemiological data collection studies. Prospective problem-specific use of our computational methods can bring significant benefits in guiding future study designs.
Prospects of Studies on Application of Complex System Theory in Power Systems
2012-01-01
Over the last decade, power systems in the world have suffered a number of blackouts caused by cascading failures. Such incidents resulted in major economic losses and social impacts, induced great concerns on the grid security and prompted people to understand and analyze the mechanism of the power system＇s cascading failures and blackouts. Conventional analysis on power systems constructs a detailed model of every component of the system, and focuses on dynamic behaviors of individual components. Therefore, it is difficult to uncover the global dynamic characteristic while deeply studying the cascading failures and the mechanism of large blackouts. The complex system theory can provide global perspectives of cascading blackouts.
Dissipative open systems theory as a foundation for the thermodynamics of linear systems
Delvenne, Jean-Charles; Sandberg, Henrik
2017-03-01
In this paper, we advocate the use of open dynamical systems, i.e. systems sharing input and output variables with their environment, and the dissipativity theory initiated by Jan Willems as models of thermodynamical systems, at the microscopic and macroscopic level alike. We take linear systems as a study case, where we show how to derive a global Lyapunov function to analyse networks of interconnected systems. We define a suitable notion of dynamic non-equilibrium temperature that allows us to derive a discrete Fourier law ruling the exchange of heat between lumped, discrete-space systems, enriched with the Maxwell-Cattaneo correction. We complete these results by a brief recall of the steps that allow complete derivation of the dissipation and fluctuation in macroscopic systems (i.e. at the level of probability distributions) from lossless and deterministic systems. This article is part of the themed issue 'Horizons of cybernetical physics'.
Dissipative open systems theory as a foundation for the thermodynamics of linear systems.
Delvenne, Jean-Charles; Sandberg, Henrik
2017-03-06
In this paper, we advocate the use of open dynamical systems, i.e. systems sharing input and output variables with their environment, and the dissipativity theory initiated by Jan Willems as models of thermodynamical systems, at the microscopic and macroscopic level alike. We take linear systems as a study case, where we show how to derive a global Lyapunov function to analyse networks of interconnected systems. We define a suitable notion of dynamic non-equilibrium temperature that allows us to derive a discrete Fourier law ruling the exchange of heat between lumped, discrete-space systems, enriched with the Maxwell-Cattaneo correction. We complete these results by a brief recall of the steps that allow complete derivation of the dissipation and fluctuation in macroscopic systems (i.e. at the level of probability distributions) from lossless and deterministic systems.This article is part of the themed issue 'Horizons of cybernetical physics'. © 2017 The Author(s).
Density functional theory for polymeric systems in 2D.
Słyk, Edyta; Roth, Roland; Bryk, Paweł
2016-06-22
We propose density functional theory for polymeric fluids in two dimensions. The approach is based on Wertheim's first order thermodynamic perturbation theory (TPT) and closely follows density functional theory for polymers proposed by Yu and Wu (2002 J. Chem. Phys. 117 2368). As a simple application we evaluate the density profiles of tangent hard-disk polymers at hard walls. The theoretical predictions are compared against the results of the Monte Carlo simulations. We find that for short chain lengths the theoretical density profiles are in an excellent agreement with the Monte Carlo data. The agreement is less satisfactory for longer chains. The performance of the theory can be improved by recasting the approach using the self-consistent field theory formalism. When the self-avoiding chain statistics is used, the theory yields a marked improvement in the low density limit. Further improvements for long chains could be reached by going beyond the first order of TPT.
A novel classification system for evolutionary aging theories
Lucas Siqueira Trindade; Toshiro eAigaki; Alexandre Afranio Peixoto; Alex eBalduino; Ivana Beatrice Mânica da Cruz; Jonathan Gardiner Heddle
2013-01-01
Theories of lifespan evolution are a source of confusion amongst aging researchers. After a century of aging research the dispute over whether the aging process is active or passive persists and a comprehensive and universally accepted theoretical model remains elusive. Evolutionary aging theories primarily dispute whether the aging process is exclusively adapted to favor the kin or exclusively non-adapted to favor the individual. Interestingly, contradictory data and theories supporting both...
Oxygenation of Stratified Reservoir Using Air Bubble Plume
Schladow, S. G.
2006-12-01
Excess nutrients loading from urban area and watershed into lakes and reservoirs increases the content of organic matter, which, through decomposition, needs increased dissolve oxygen (DO). Many eutrophic reservoirs and lakes cannot meet the DO requirement during stratified season and suffers from the hypolimnetic anoxia. As a result, benthic sediment produces anoxic products such as methane, hydrogen sulphide, ammonia, iron, manganese, and phosphorus. In order to address the hypolimnetic anoxia, oxygen is artificially supplied into reservoir using an aeration system (i.e., bubbler). The most common result of lake/reservoir aeration is to destratify the reservoir so that the water body may completely mix under natural phenomena and remain well oxygenated throughout. Other advantages of destratification are: (1) allows warm- water fish to inhabit the entire reservoir, (2) suppress the nutrient release from sediment, and (3) decreases the algal growth by sending them to the darker zone. A one-dimensional reservoir-bubbler model is developed and applied to examine the effects of an aeration system on mixing and dissolved oxygen dynamics in the Upper Peirce Reservoir, Singapore. After introduction of the aeration system in the reservoir, it was found that the hypolimnetic DO increased significantly, and the concentration of algae, soluble manganese and iron substantially reduced. It is found that the reservoir-bubbler model predicts the mixing (temperature as mixing parameter) and dissolved oxygen concentration in the reservoir with acceptable accuracy. It is shown in terms of bubbler mechanical efficiency (i.e., operating cost) and total DO contribution from the aeration system into the reservoir that the selections of airflow rate per diffuser, air bubble radius, and total number of diffusers are important design criteria of a bubbler system. However, the overall bubbler design also depends on the reservoir size and stratified area of interest, ambient climate, and
Second order closure for stratified convection: bulk region and overshooting
Biferale, L; Sbragaglia, M; Scagliarini, A; Toschi, F; Tripiccione, R
2011-01-01
The parameterization of small-scale turbulent fluctuations in convective systems and in the presence of strong stratification is a key issue for many applied problems in oceanography, atmospheric science and planetology. In the presence of stratification, one needs to cope with bulk turbulent fluctuations and with inversion regions, where temperature, density -or both- develop highly non-linear mean profiles due to the interactions between the turbulent boundary layer and the unmixed -stable- flow above/below it. We present a second order closure able to cope simultaneously with both bulk and boundary layer regions, and we test it against high-resolution state-of-the-art 2D numerical simulations in a convective and stratified belt for values of the Rayleigh number, up to Ra = 10^9. Data are taken from a Rayleigh-Taylor system confined by the existence of an adiabatic gradient.
Causal Fermion Systems as a Candidate for a Unified Physical Theory
Finster, Felix; Kleiner, Johannes
2015-01-01
The theory of causal fermion systems is an approach to describe fundamental physics. Giving quantum mechanics, general relativity and quantum field theory as limiting cases, it is a candidate for a unified physical theory. We here give a non-technical introduction.
Applied Systemic Theory and Educational Psychology: Can the Twain Ever Meet?
Pellegrini, Dario W.
2009-01-01
This article reflects on the potential benefits of applying systemic theory to the work of educational psychologists (EPs). It reviews developments in systemic thinking over time, and discusses the differences between more directive "first order" versus collaborative "second order" approaches. It considers systemic theories and…
Designing sociotechnical systems with cognitive work analysis: putting theory back into practice.
Read, Gemma J M; Salmon, Paul M; Lenné, Michael G; Stanton, Neville A
2015-01-01
Cognitive work analysis (CWA) is a framework of methods for analysing complex sociotechnical systems. However, the translation from the outputs of CWA to design is not straightforward. Sociotechnical systems theory provides values and principles for the design of sociotechnical systems which may offer a theoretically consistent basis for a design approach for use with CWA. This article explores the extent to which CWA and sociotechnical systems theory offer complementary perspectives and presents an abstraction hierarchy (AH), based on a review of literature, that describes an 'optimal' CWA and sociotechnical systems theory design system. The optimal AH is used to assess the extent to which current CWA-based design practices, uncovered through a survey of CWA practitioners, aligns with sociotechnical systems theory. Recommendations for a design approach that would support the integration of CWA and sociotechnical systems theory design values and principles are also derived.
Strongly Stratified Turbulence Wakes and Mixing Produced by Fractal Wakes
Dimitrieva, Natalia; Redondo, Jose Manuel; Chashechkin, Yuli; Fraunie, Philippe; Velascos, David
2017-04-01
-stationary dynamicss and structure of stratified fluid flows around a wedge were also studied based of the fundamental equations set using numerical modeling. Due to breaking of naturally existing background diffusion flux of stratifying agent by an impermeable surface of the wedge a complex multi-level vortex system of compensatory fluid motions is formed around the obstacle. The flow is characterized by a wide range of values of internal scales that are absent in a homogeneous liquid. Numerical solution of the fundamental system with the boundary conditions is constructed using a solver such as stratifiedFoam developed within the frame of the open source computational package OpenFOAM using the finite volume method. The computations were performed in parallel using computing resources of the Scientific Research Supercomputer Complex of MSU (SRCC MSU) and the technological platform UniHUB. The evolution of the flow pattern of the wedge by stratified flow has been demonstrated. The complex structure of the fields of physical quantities and their gradients has been shown. Observed in experiment are multiple flow components, including upstream disturbances, internal waves and the downstream wake with submerged transient vortices well reproduced. Structural elements of flow differ in size and laws of variation in space and time. Rich fine flow structure visualized in vicinity and far from the obstacle. The global efficiency of the mixing process is measured and compared with previous estimates of mixing efficiency.
A probability theory for non-equilibrium gravitational systems
Peñarrubia, Jorge
2015-08-01
This paper uses dynamical invariants to describe the evolution of collisionless systems subject to time-dependent gravitational forces without resorting to maximum-entropy probabilities. We show that collisionless relaxation can be viewed as a special type of diffusion process in the integral-of-motion space. In time-varying potentials with a fixed spatial symmetry the diffusion coefficients are closely related to virial quantities, such as the specific moment of inertia, the virial factor and the mean kinetic and potential energy of microcanonical particle ensembles. The non-equilibrium distribution function is found by convolving the initial distribution function with the Green function that solves Einstein's equation for freely diffusing particles. Such a convolution also yields a natural solution to the Fokker-Planck equations in the energy space. Our mathematical formalism can be generalized to potentials with a time-varying symmetry, where diffusion extends over multiple dimensions of the integral-of-motion space. The new probability theory is in many ways analogous to stochastic calculus, with two significant differences: (i) the equations of motion that govern the trajectories of particles are fully deterministic, and (ii) the diffusion coefficients can be derived self-consistently from microcanonical phase-space averages without relying on ergodicity assumptions. For illustration we follow the cold collapse of N-body models in a time-dependent logarithmic potential. Comparison between the analytical and numerical results shows excellent agreement in regions where the potential evolution does not depart too strongly from the adiabatic regime.
Solar system constraints on multifield theories of modified dynamics
Sanders, R. H.
2006-01-01
Any viable theory of modified Newtonian dynamics (MOND) as modified gravity is likely to require fields in addition to the usual tensor field of General Relativity. For these theories, the MOND phenomenology emerges as an effective fifth force probably associated with a scalar field. Here, I
Ensemble Bayesian forecasting system Part I: Theory and algorithms
Herr, Henry D.; Krzysztofowicz, Roman
2015-05-01
The ensemble Bayesian forecasting system (EBFS), whose theory was published in 2001, is developed for the purpose of quantifying the total uncertainty about a discrete-time, continuous-state, non-stationary stochastic process such as a time series of stages, discharges, or volumes at a river gauge. The EBFS is built of three components: an input ensemble forecaster (IEF), which simulates the uncertainty associated with random inputs; a deterministic hydrologic model (of any complexity), which simulates physical processes within a river basin; and a hydrologic uncertainty processor (HUP), which simulates the hydrologic uncertainty (an aggregate of all uncertainties except input). It works as a Monte Carlo simulator: an ensemble of time series of inputs (e.g., precipitation amounts) generated by the IEF is transformed deterministically through a hydrologic model into an ensemble of time series of outputs, which is next transformed stochastically by the HUP into an ensemble of time series of predictands (e.g., river stages). Previous research indicated that in order to attain an acceptable sampling error, the ensemble size must be on the order of hundreds (for probabilistic river stage forecasts and probabilistic flood forecasts) or even thousands (for probabilistic stage transition forecasts). The computing time needed to run the hydrologic model this many times renders the straightforward simulations operationally infeasible. This motivates the development of the ensemble Bayesian forecasting system with randomization (EBFSR), which takes full advantage of the analytic meta-Gaussian HUP and generates multiple ensemble members after each run of the hydrologic model; this auxiliary randomization reduces the required size of the meteorological input ensemble and makes it operationally feasible to generate a Bayesian ensemble forecast of large size. Such a forecast quantifies the total uncertainty, is well calibrated against the prior (climatic) distribution of
Xue, Jingxin
The article aims to completely, systematically and objectively analyze the current situation of Entrepreneurship Education in China with Ecological Systems Theory. From this perspective, the author discusses the structure, function and its basic features of higher education entrepreneur services network system, and puts forward the opinion that every entrepreneurship organization in higher education institution does not limited to only one platform. Different functional supporting platforms should be combined closed through composite functional organization to form an integrated network system, in which each unit would impels others' development.
Interface Theories for (Asynchronously Communicating Modal I/O-Transition Systems
Sebastian S. Bauer
2011-01-01
Full Text Available Interface specifications play an important role in component-based software development. An interface theory is a formal framework supporting composition, refinement and compatibility of interface specifications. We present different interface theories which use modal I/O-transition systems as their underlying domain for interface specifications: synchronous interface theories, which employ a synchronous communication schema, as well as a novel interface theory for asynchronous communication where components communicate via FIFO-buffers.
Interface Theories for (A)synchronously Communicating Modal I/O-Transition Systems
Bauer, Sebastian S; Janisch, Stephan; 10.4204/EPTCS.46.1
2011-01-01
Interface specifications play an important role in component-based software development. An interface theory is a formal framework supporting composition, refinement and compatibility of interface specifications. We present different interface theories which use modal I/O-transition systems as their underlying domain for interface specifications: synchronous interface theories, which employ a synchronous communication schema, as well as a novel interface theory for asynchronous communication where components communicate via FIFO-buffers.
Epistemic Information in Stratified M-Spaces
Mark Burgin
2011-12-01
Full Text Available Information is usually related to knowledge. However, the recent development of information theory demonstrated that information is a much broader concept, being actually present in and virtually related to everything. As a result, many unknown types and kinds of information have been discovered. Nevertheless, information that acts on knowledge, bringing new and updating existing knowledge, is of primary importance to people. It is called epistemic information, which is studied in this paper based on the general theory of information and further developing its mathematical stratum. As a synthetic approach, which reveals the essence of information, organizing and encompassing all main directions in information theory, the general theory of information provides efficient means for such a study. Different types of information dynamics representation use tools of mathematical disciplines such as the theory of categories, functional analysis, mathematical logic and algebra. Here we employ algebraic structures for exploration of information and knowledge dynamics. In Introduction (Section 1, we discuss previous studies of epistemic information. Section 2 gives a compressed description of the parametric phenomenological definition of information in the general theory of information. In Section 3, anthropic information, which is received, exchanged, processed and used by people is singled out and studied based on the Componential Triune Brain model. One of the basic forms of anthropic information called epistemic information, which is related to knowledge, is analyzed in Section 4. Mathematical models of epistemic information are studied in Section 5. In Conclusion, some open problems related to epistemic information are given.
New Concepts and Theories For Intelligent Control of Cellular Manufacturing Systems
Langer, Gilad
1996-01-01
This paper will present some new theories such as biological manufacturing system, the fractal factory theory, holonic manufacturing systems, and multi-agent theory in the context of manufacturing systems. The objective of the paper is to show how these theories can contribute to develop the new...... concepts that are required for controlling the manufacturing systems of the future. Thereafter it will present the potential for improvement of the manufacturing system by introduction and implementation of these theories. The paper tries to encapsulate the main area of my Ph.D. thesis research which...... will evolve around the idea of integrating intelligent elements into the control systems of the manufacturing systems. The research will concentrate on integration of manufacturing units by use of intelligent control mechanisms, information technology and the material handling as the key integrators....
New Concepts and Theories For Intelligent Control of Cellular Manufacturing Systems
Langer, Gilad
1996-01-01
concepts that are required for controlling the manufacturing systems of the future. Thereafter it will present the potential for improvement of the manufacturing system by introduction and implementation of these theories. The paper tries to encapsulate the main area of my Ph.D. thesis research which......This paper will present some new theories such as biological manufacturing system, the fractal factory theory, holonic manufacturing systems, and multi-agent theory in the context of manufacturing systems. The objective of the paper is to show how these theories can contribute to develop the new...... will evolve around the idea of integrating intelligent elements into the control systems of the manufacturing systems. The research will concentrate on integration of manufacturing units by use of intelligent control mechanisms, information technology and the material handling as the key integrators....
Magnetic flux concentrations from turbulent stratified convection
Käpylä, P J; Kleeorin, N; Käpylä, M J; Rogachevskii, I
2015-01-01
(abridged) Context: The mechanisms that cause the formation of sunspots are still unclear. Aims: We study the self-organisation of initially uniform sub-equipartition magnetic fields by highly stratified turbulent convection. Methods: We perform simulations of magnetoconvection in Cartesian domains that are $8.5$-$24$ Mm deep and $34$-$96$ Mm wide. We impose either a vertical or a horizontal uniform magnetic field in a convection-driven turbulent flow. Results: We find that super-equipartition magnetic flux concentrations are formed near the surface with domain depths of $12.5$ and $24$ Mm. The size of the concentrations increases as the box size increases and the largest structures ($20$ Mm horizontally) are obtained in the 24 Mm deep models. The field strength in the concentrations is in the range of $3$-$5$ kG. The concentrations grow approximately linearly in time. The effective magnetic pressure measured in the simulations is positive near the surface and negative in the bulk of the convection zone. Its ...
Affect Theory and Autoethnography in Ordinary Information Systems
Bødker, Mads; Chamberlain, Alan
2016-01-01
This paper uses philosophical theories of affect as a lens for exploring autoethnographic renderings of everyday experience with information technology. Affect theories, in the paper, denote a broad trend in post-humanistic philosophy that explores sensation and feeling as emergent and relational...... precognitive forces that impinge on a body and its capacity to act. A necessarily truncated account of affect theory, and three autoethnographic vignettes are presented to complement the philosophical exposition and to provide reflections on possible empirical tactics for affective research in IS. Inspired...
Affect Theory and Autoethnography in Ordinary Information Systems
Bødker, Mads; Chamberlain, Alan
2016-01-01
This paper uses philosophical theories of affect as a lens for exploring autoethnographic renderings of everyday experience with information technology. Affect theories, in the paper, denote a broad trend in post-humanistic philosophy that explores sensation and feeling as emergent and relational...... precognitive forces that impinge on a body and its capacity to act. A necessarily truncated account of affect theory, and three autoethnographic vignettes are presented to complement the philosophical exposition and to provide reflections on possible empirical tactics for affective research in IS. Inspired...
A Fault Diagnosis Method of Power Systems Based on Gray System Theory
Huang Darong
2015-01-01
Full Text Available To provide some decision-making suggestions for fault diagnosis in power systems, a new model for identifying fault component is constructed by using Gray theory. Firstly, the basic concepts of Gray theory are introduced and explained in detail. And then the recognition algorithm of the power supply interrupted districts and the assignment principle of fault state vectors are depicted according to the working principle of protective relays (PRs and circuit breakers (CBs. Secondly, based on the concept of the Gray correlation degree, the fault information explanation degree model is constructed and the judging method of malfunction and rejection for PRs and CBs is established. Meanwhile, to achieve the goal of the fault diagnosis, the fault diagnosis procedure that determined which components malfunction is designed for power systems. Finally, some simple experiments have already verified that the proposed method and model are effective and reasonable and the trend of further research is analyzed and summarized.
Lefeuve-Mesgouez, Gaëlle; Chiavassa, Guillaume; Lombard, Bruno
2012-01-01
Wave propagation in a stratified fluid / porous medium is studied here using analytical and numerical methods. The semi-analytical method is based on an exact stiffness matrix method coupled with a matrix conditioning procedure, preventing the occurrence of poorly conditioned numerical systems. Special attention is paid to calculating the Fourier integrals. The numerical method is based on a high order finite-difference time-domain scheme. Mesh refinement is applied near the interfaces to discretize the slow compressional diffusive wave predicted by Biot's theory. Lastly, an immersed interface method is used to discretize the boundary conditions. The numerical benchmarks are based on realistic soil parameters and on various degrees of hydraulic contact at the fluid / porous boundary. The time evolution of the acoustic pressure and the porous velocity is plotted in the case of one and four interfaces. The excellent level of agreement found to exist between the two approaches confirms the validity of both metho...
Fernandez, Charles; Soize, Christian; Gagliardini, Laurent
2009-01-01
The fuzzy structure theory was introduced 20 years ago in order to model the effects of complex subsystems imprecisely known on a master structure. This theory was only aimed at structural dynamics. In this paper, an extension of that theory is proposed in developing an elastoacoustic element useful to model sound-insulation layers for computational vibroacoustics of complex systems. The simplified model constructed enhances computation time and memory allocation because the number of physical and generalized degrees of freedom in the computational vibroacoustic model is not increased. However, these simplifications introduce model uncertainties. In order to take into account these uncertainties, the nonparametric probabilistic approach recently introduced is used. A robust simplified model for sound-insulation layers is then obtained. This model is controlled by a small number of physical and dispersion parameters. First, the extension of the fuzzy structure theory to elastoacoustic element is presented. Second, the computational vibroacoustic model including such an elastoacoustic element to model sound-insulation layer is given. Then, a design methodology to identify the model parameters with experiments is proposed and is experimentally validated. Finally, the theory is applied to an uncertain vibroacoustic system.
Transport through correlated systems with density functional theory
Kurth, S.; Stefanucci, G.
2017-10-01
We present recent advances in density functional theory (DFT) for applications in the field of quantum transport, with particular emphasis on transport through strongly correlated systems. We review the foundations of the popular Landauer–Büttiker(LB) + DFT approach. This formalism, when using approximations to the exchange-correlation (xc) potential with steps at integer occupation, correctly captures the Kondo plateau in the zero bias conductance at zero temperature but completely fails to capture the transition to the Coulomb blockade (CB) regime as the temperature increases. To overcome the limitations of LB + DFT, the quantum transport problem is treated from a time-dependent (TD) perspective using TDDFT, an exact framework to deal with nonequilibrium situations. The steady-state limit of TDDFT shows that in addition to an xc potential in the junction, there also exists an xc correction to the applied bias. Open shell molecules in the CB regime provide the most striking examples of the importance of the xc bias correction. Using the Anderson model as guidance we estimate these corrections in the limit of zero bias. For the general case we put forward a steady-state DFT which is based on one-to-one correspondence between the pair of basic variables, steady density on and steady current across the junction and the pair local potential on and bias across the junction. Like TDDFT, this framework also leads to both an xc potential in the junction and an xc correction to the bias. Unlike TDDFT, these potentials are independent of history. We highlight the universal features of both xc potential and xc bias corrections for junctions in the CB regime and provide an accurate parametrization for the Anderson model at arbitrary temperatures and interaction strengths, thus providing a unified DFT description for both Kondo and CB regimes and the transition between them.
A stochastic perturbation theory for non-autonomous systems
Moon, W., E-mail: wm275@damtp.cam.ac.uk [Yale University, New Haven, Connecticut 06520-8109 (United States); Wettlaufer, J. S., E-mail: wettlaufer@maths.ox.ac.uk [Yale University, New Haven, Connecticut 06520-8109 (United States); Mathematical Institute, University of Oxford, Oxford OX2 6GG (United Kingdom)
2013-12-15
We develop a perturbation theory for a class of first order nonlinear non-autonomous stochastic ordinary differential equations that arise in climate physics. The perturbative procedure produces moments in terms of integral delay equations, whose order by order decay is characterized in a Floquet-like sense. Both additive and multiplicative sources of noise are discussed and the question of how the nature of the noise influences the results is addressed theoretically and numerically. By invoking the Martingale property, we rationalize the transformation of the underlying Stratonovich form of the model to an Ito form, independent of whether the noise is additive or multiplicative. The generality of the analysis is demonstrated by developing it both for a Brownian particle moving in a periodically forced quartic potential, which acts as a simple model of stochastic resonance, as well as for our more complex climate physics model. The validity of the approach is shown by comparison with numerical solutions. The particular climate dynamics problem upon which we focus involves a low-order model for the evolution of Arctic sea ice under the influence of increasing greenhouse gas forcing ΔF{sub 0}. The deterministic model, developed by Eisenman and Wettlaufer [“Nonlinear threshold behavior during the loss of Arctic sea ice,” Proc. Natl. Acad. Sci. U.S.A. 106(1), 28–32 (2009)] exhibits several transitions as ΔF{sub 0} increases and the stochastic analysis is used to understand the manner in which noise influences these transitions and the stability of the system.
A stochastic perturbation theory for non-autonomous systems
Moon, Woosok; Wettlaufer, John
2014-05-01
We develop a perturbation theory for a class of first order nonlinear non-autonomous stochastic ordinary differential equations that arise in climate physics. The perturbative procedure produces moments in terms of integral delay equations, whose order by order decay is characterized in a Floquet-like sense. Both additive and multiplicative sources of noise are discussed and the question of how the nature of the noise influences the results is addressed theoretically and numerically. By invoking the Martingale property, we rationalize the transformation of the underlying Stratonovich form of the model to an Ito form, independent of whether the noise is additive or multiplicative. The generality of the analysis is demonstrated by developing it both for a Brownian particle moving in a periodically forced quartic potential, which acts as a simple model of stochastic resonance, as well as for our more complex climate physics model. The validity of the approach is shown by comparison with numerical solutions. The particular climate dynamics problem upon which we focus involves a low-order model for the evolution of Arctic sea ice under the influence of increasing greenhouse gas forcing ΔF0. The deterministic model, developed by Eisenman and Wettlaufer EW09 exhibits several transitions as ΔF0 increases and the stochastic analysis is used to understand the manner in which noise influences these transitions and the stability of the system. Eisenman, I., and J. S. Wettlaufer, 'Nonlinear threshold behavior during the loss of Arctic sea ice,' Proc. Natl. Acad. Sci. USA, 106, 28-32, 2009.
A Model for Predicting Holdup and Pressure Drop in Gas-Liquid Stratified Flow
无
2001-01-01
The time-dependent liquid film thickness and pressure drop were measured by using parallel-wire conductance probes and capacitance differential-preesure transducers. Applying the eddy viscosity theory and an appropriate correlation of interfacial sear stress,a new two-dimensional separated model of holdup and pressure drop of turbulent/turbulent gas-liquid stratified flow was presented. Prediction results agreed well with experimental data.
Magnetorotational instability in stratified, weakly ionised accretion discs
Salmeron, Roberto Aureliano; Salmeron, Raquel; Wardle, Mark
2003-01-01
We present a linear analysis of the vertical structure and growth of the magnetorotational instability in stratified, weakly ionised accretion discs, such as protostellar and quiescent dwarf novae systems. The method includes the effects of the magnetic coupling, the conductivity regime of the fluid and the strength of the magnetic field, which is initially vertical. The conductivity is treated as a tensor and assumed constant with height. We obtained solutions for the structure and growth rate of global unstable modes for different conductivity regimes, strengths of the initial magnetic field and coupling between ionised and neutral components of the fluid. The envelopes of short-wavelenght perturbations are determined by the action of competing local growth rates at different heights, driven by the vertical stratification of the disc. Ambipolar diffusion perturbations peak consistently higher above the midplane than modes including Hall conductivity. For weak coupling, perturbations including the Hall effec...
From a systems theory of sociology to modeling the onset and evolution of criminality
Bellomo, N; Knopoff, D; Soler, J
2014-01-01
This paper proposes a systems theory approach to the modeling of onset and evolution of criminality in a territory, which aims at capturing the complexity features of social systems. Complexity is related to the fact that individuals have the ability to develop specific heterogeneously distributed strategies, which depend also on those expressed by the other individuals. The modeling is developed by methods of generalized kinetic theory where interactions and decisional processes are modeled by theoretical tools of stochastic game theory.
Hildegard Peplau meets family systems nursing: innovation in theory-based practice.
Forchuk, C; Dorsay, J P
1995-01-01
Nursing theories which have evolved from mental health--psychiatric nursing have focused on the individual nurse-client relationship. Other nursing theories generally focus on the individual as client. Therefore, nurses working with families may have difficulty in applying these frameworks to their practice. Nursing theories need to be expanded to include families, groups and communities more explicitly. The well established theory of Hildegard Peplau, which previous studies have found to be the theory most frequently used by psychiatric nurses, and the family systems nursing theory of Wright and Leahey share a complementary focus. Both theories form part of the interpersonal paradigm of nursing; both view nursing from an interactional perspective, rather than focusing on individuals. Use of a combined theoretical approach offers several advantages. The approach explicitly considers both the individual and the family. The combination provides grounding for family work in an articulated nursing theory.
Sung, Dia; You, Yeongmahn; Song, Ji Hoon
2008-01-01
The purpose of this research is to explore the possibility of viable learning organizations based on identifying viable organizational learning mechanisms. Two theoretical foundations, complex system theory and viable system theory, have been integrated to provide the rationale for building the sustainable organizational learning mechanism. The…
Development of the trauma emergency care system based on the three links theory
JIANG Guan-yu; SHEN Wei-feng; GAN Jian-xin
2005-01-01
The three links theory applied in trauma emergency care system refers to an integrated system with the three important components of trauma emergency care system, viz. prehospital trauma services, hospital trauma services and critical care services. The development of the trauma emergency care system should be guided by the three links theory so as to set up a practical and highly efficient system: a prompt operating and monitoring transportation system, a smooth and real-time information system, a rational and sustainable system of regulations and contingency plans, and a system for cultivating all-round trauma physicians.
Rana, Mohammad Bakhtiar; Morgan, Glenn
2016-01-01
Business systems theory (BST) lies at the intersection of organization theory, political economy and sociology. Over the last 25 years, it has been increasingly used to analyse not just firms within national business systems but also the nature of international business and its interactions both ...
control theory to systems described by partial differential equations. The intent is not to advance the theory of partial differential equations per se. Thus all considerations will be restricted to the more familiar equations of the type which often occur in mathematical physics. Specifically, the distributed parameter systems under consideration are represented by a set of field
Azaola, Marta Cristina
2012-01-01
The paper reflects upon the principles and practice of an alternative educational system operating in rural Mexico in the light of Bourdieu's theory of cultural and social reproduction. Bourdieu's theory seeks to explain processes of reproduction of power relations within schools and society; whereas alternative educational systems seek to expand…
Linear operators and linear systems an analytical approach to control theory
Partington, Jonathan R
2004-01-01
This book presents an introduction to the common ground between operator theory and linear systems theory. Suitable for students of functional analysis, this book also acts as an introduction to a mathematical approach to systems and control for graduate students in departments of applied mathematics or engineering.
What is the Role of Legal Systems in Financial Intermediation? Theory and Evidence
Bottazzi, L.; Da Rin, M.; Hellmann, T.
2008-01-01
We develop a theory and empirical test of how the legal system affects the relationship between venture capitalists and entrepreneurs. The theory uses a double moral hazard framework to show how optimal contracts and investor actions depend on the quality of the legal system. The empirical evidence
Azaola, Marta Cristina
2012-01-01
The paper reflects upon the principles and practice of an alternative educational system operating in rural Mexico in the light of Bourdieu's theory of cultural and social reproduction. Bourdieu's theory seeks to explain processes of reproduction of power relations within schools and society; whereas alternative educational systems seek to expand…
What is the Role of Legal Systems in Financial Intermediation? Theory and Evidence
Bottazzi, L.; Da Rin, M.; Hellmann, T.
2008-01-01
We develop a theory and empirical test of how the legal system affects the relationship between venture capitalists and entrepreneurs. The theory uses a double moral hazard framework to show how optimal contracts and investor actions depend on the quality of the legal system. The empirical evidence
Set Theory Applied to Uniquely Define the Inputs to Territorial Systems in Emergy Analyses
The language of set theory can be utilized to represent the emergy involved in all processes. In this paper we use set theory in an emergy evaluation to ensure an accurate representation of the inputs to territorial systems. We consider a generic territorial system and we describ...
Tsai, Chung-Hung
2014-05-07
Telehealth has become an increasingly applied solution to delivering health care to rural and underserved areas by remote health care professionals. This study integrated social capital theory, social cognitive theory, and the technology acceptance model (TAM) to develop a comprehensive behavioral model for analyzing the relationships among social capital factors (social capital theory), technological factors (TAM), and system self-efficacy (social cognitive theory) in telehealth. The proposed framework was validated with 365 respondents from Nantou County, located in Central Taiwan. Structural equation modeling (SEM) was used to assess the causal relationships that were hypothesized in the proposed model. The finding indicates that elderly residents generally reported positive perceptions toward the telehealth system. Generally, the findings show that social capital factors (social trust, institutional trust, and social participation) significantly positively affect the technological factors (perceived ease of use and perceived usefulness respectively), which influenced usage intention. This study also confirmed that system self-efficacy was the salient antecedent of perceived ease of use. In addition, regarding the samples, the proposed model fitted considerably well. The proposed integrative psychosocial-technological model may serve as a theoretical basis for future research and can also offer empirical foresight to practitioners and researchers in the health departments of governments, hospitals, and rural communities.
Chung-Hung Tsai
2014-05-01
Full Text Available Telehealth has become an increasingly applied solution to delivering health care to rural and underserved areas by remote health care professionals. This study integrated social capital theory, social cognitive theory, and the technology acceptance model (TAM to develop a comprehensive behavioral model for analyzing the relationships among social capital factors (social capital theory, technological factors (TAM, and system self-efficacy (social cognitive theory in telehealth. The proposed framework was validated with 365 respondents from Nantou County, located in Central Taiwan. Structural equation modeling (SEM was used to assess the causal relationships that were hypothesized in the proposed model. The finding indicates that elderly residents generally reported positive perceptions toward the telehealth system. Generally, the findings show that social capital factors (social trust, institutional trust, and social participation significantly positively affect the technological factors (perceived ease of use and perceived usefulness respectively, which influenced usage intention. This study also confirmed that system self-efficacy was the salient antecedent of perceived ease of use. In addition, regarding the samples, the proposed model fitted considerably well. The proposed integrative psychosocial-technological model may serve as a theoretical basis for future research and can also offer empirical foresight to practitioners and researchers in the health departments of governments, hospitals, and rural communities.
Incomplete information system and rough set theory models and attribute reductions
Yang, Xibei
2012-01-01
This study of the theory of generalizations of rough-set models in incomplete information systems discusses not only the regular attributes but also the criteria in these systems, and presents practical approaches to computing a number of reducts.